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**Technical support**
Technical support:
Technical support are also known as a tech support is a call centre type customer service provided by companies to advise and assist registered users with issues concerning their technical products. Traditionally done on the phone, technical support can now be conducted online or through chat. At present, most large and mid-size companies have outsourced their tech support operations. Many companies provide discussion boards for users of their products to interact; such forums allow companies to reduce their support costs without losing the benefit of customer feedback.
Outsourcing tech support:
With the increasing use of technology in modern times, there is a growing requirement to provide technical support. Many organizations locate their technical support departments or call centers in countries or regions with lower costs. Dell was amongst the first companies to outsource their technical support and customer service departments to India in 2001. There has also been a growth in companies specializing in providing technical support to other organizations. These are often referred to as MSPs (Managed Service Providers).For businesses needing to provide technical support, outsourcing allows them to maintain high availability of service. Such need may result from peaks in call volumes during the day, periods of high activity due to the introduction of new products or maintenance service packs, or the requirement to provide customers with a high level of service at a low cost to the business. For businesses needing technical support assets, outsourcing enables their core employees to focus more on their work in order to maintain productivity. It also enables them to utilize specialized personnel whose technical knowledge base and experience may exceed the scope of the business, thus providing a higher level of technical support to their employees.
Multi-level tech support:
Technical support is often subdivided into tiers, or levels, in order to better serve a business or customer base. The number of levels a business uses to organize their technical support group is dependent on the business's needs regarding their ability to sufficiently serve their customers or users. The reason for providing a multi-tiered support system instead of one general support group is to provide the best possible service in the most efficient possible manner. Success of the organizational structure is dependent on the technicians' understanding of their level of responsibility and commitments, their customer response time commitments, and when to appropriately escalate an issue and to which level. A common support structure revolves around a three-tiered technical support system. Remote computer repair is a method for troubleshooting software related problems via remote desktop connections.
Multi-level tech support:
L1 Support The first job of a Tier I specialist is to gather the customer's information and to determine the customer's issue by analyzing the symptoms and figuring out the underlying problem. When analyzing the symptoms, it is important for the technician to identify what the customer is trying to accomplish so that time is not wasted on "attempting to solve a symptom instead of a problem."Once identification of the underlying problem is established, the specialist can begin sorting through the possible solutions available. Technical support specialists in this group typically handle straightforward and simple problems while "possibly using some kind of knowledge management tool." This includes troubleshooting methods such as verifying physical layer issues, resolving username and password problems, uninstalling/reinstalling basic software applications, verification of proper hardware and software set up, and assistance with navigating around application menus. Personnel at this level have a basic to general understanding of the product or service and may not always contain the competency required for solving complex issues. Nevertheless, the goal for this group is to handle 70–80% of the user problems before finding it necessary to escalate the issue to a higher level.
Multi-level tech support:
L2 Support Tier II (or Level 2, abbreviated as T2 or L2) is a more in-depth technical support level than Tier I and therefore costs more as the technicians are more experienced and knowledgeable on a particular product or service. It is synonymous with level 2 support, support line 2, administrative level support, and various other headings denoting advanced technical troubleshooting and analysis methods. Technicians in this realm of knowledge are responsible for assisting Tier I personnel in solving basic technical problems and for investigating elevated issues by confirming the validity of the problem and seeking for known solutions related to these more complex issues. However, prior to the troubleshooting process, it is important that the technician review the work order to see what has already been accomplished by the Tier I technician and how long the technician has been working with the particular customer. This is a key element in meeting both the customer and business needs as it allows the technician to prioritize the troubleshooting process and properly manage their time.If a problem is new and/or personnel from this group cannot determine a solution, they are responsible for elevating this issue to the Tier III technical support group. In addition, many companies may specify that certain troubleshooting solutions be performed by this group to help ensure the intricacies of a challenging issue are solved by providing experienced and knowledgeable technicians. This may include, but is not limited to, onsite installations or replacement of various hardware components, software repair, diagnostic testing, or the utilization of remote control tools to take over the user's machine for the sole purpose of troubleshooting and finding a solution to the problem.
Multi-level tech support:
L3 Support Tier III (or Level 3, abbreviated as T3 or L3) is the highest level of support in a three-tiered technical support model responsible for handling the most difficult or advanced problems. It is synonymous with level 3 support, 3rd line support, back-end support, support line 3, high-end support, and various other headings denoting expert level troubleshooting and analysis methods. These individuals are experts in their fields and are responsible for not only assisting both Tier I and Tier II personnel, but with the research and development of solutions to new or unknown issues. Note that Tier III technicians have the same responsibility as Tier II technicians in reviewing the work order and assessing the time already spent with the customer so that the work is prioritized and time management is sufficiently utilized. If it is at all possible, the technician will work to solve the problem with the customer as it may become apparent that the Tier I and/or Tier II technicians simply failed to discover the proper solution. Upon encountering new problems, however, Tier III personnel must first determine whether or not to solve the problem and may require the customer's contact information so that the technician can have adequate time to troubleshoot the issue and find a solution. It is typical for a developer or someone who knows the code or backend of the product, to be the Tier 3 support person.
Multi-level tech support:
In some instances, an issue may be so problematic to the point where the product cannot be salvaged and must be replaced. Such extreme problems are also sent to the original developers for in-depth analysis. If it is determined that a problem can be solved, this group is responsible for designing and developing one or more courses of action, evaluating each of these courses in a test case environment, and implementing the best solution to the problem. While not universally used, a fourth level often represents an escalation point beyond the organization. L4 support is generally a hardware or software vendor.
Scams:
A common scam typically involves a cold caller claiming to be from a technical support department of a company like Microsoft. Such cold calls are often made from call centers based in India to users in English-speaking countries, although increasingly these scams operate within the same country. The scammer will instruct the user to download a remote desktop program and once connected, use social engineering techniques that typically involve Windows components to persuade the victim that they need to pay in order for the computer to be fixed and then proceeds to steal money from the victim's credit card. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Olivetti X/OS**
Olivetti X/OS:
X/OS was a Unix from the computer manufacturer Olivetti. It was based on 4.2BSD with some UNIX System V support. It ran on their LSX line of computers, which was based on the Motorola 68000-series CPUs. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Metallothionein-3**
Metallothionein-3:
Metallothionein-3 (also known as Growth Inhibitory Factor) is a protein that in humans is encoded by the MT3 gene.
It is a 68-amino acid peptide (20 of which are cysteine) that is abnormally under-expressed in the brains of patients with Alzheimer's disease.
Metallothionein-3 is a member of the metallothionein family of proteins. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Neuron**
Neuron:
Within a nervous system, a neuron, neurone, or nerve cell is an electrically excitable cell that fires electric signals called action potentials across a neural network. Neurons communicate with other cells via synapses - specialized connections that commonly use minute amounts of chemical neurotransmitters to pass the electric signal from the presynaptic neuron to the target cell through the synaptic gap. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells.
Neuron:
Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are functionally connected together, they form what is called a neural circuit.
Neuron:
Neurons are special cells which are made up of some structures that are common to all other eukaryotic cells such as the cell body (soma), a nucleus, smooth and rough endoplasmic reticulum, Golgi apparatus, mitochondria, and other cellular components. Additionally, neurons have other unique structures such as dendrites, and a single axon. The soma is a compact structure, and the axon and dendrites are filaments extruding from the soma. Dendrites typically branch profusely and extend a few hundred micrometers from the soma. The axon leaves the soma at a swelling called the axon hillock and travels for as far as 1 meter in humans or more in other species. It branches but usually maintains a constant diameter. At the farthest tip of the axon's branches are axon terminals, where the neuron can transmit a signal across the synapse to another cell. Neurons may lack dendrites or have no axon. The term neurite is used to describe either a dendrite or an axon, particularly when the cell is undifferentiated.
Neuron:
Most neurons receive signals via the dendrites and soma and send out signals down the axon. At the majority of synapses, signals cross from the axon of one neuron to a dendrite of another. However, synapses can connect an axon to another axon or a dendrite to another dendrite.
Neuron:
The signaling process is partly electrical and partly chemical. Neurons are electrically excitable, due to maintenance of voltage gradients across their membranes. If the voltage changes by a large enough amount over a short interval, the neuron generates an all-or-nothing electrochemical pulse called an action potential. This potential travels rapidly along the axon and activates synaptic connections as it reaches them. Synaptic signals may be excitatory or inhibitory, increasing or reducing the net voltage that reaches the soma.
Neuron:
In most cases, neurons are generated by neural stem cells during brain development and childhood. Neurogenesis largely ceases during adulthood in most areas of the brain.
Nervous system:
Neurons are the primary components of the nervous system, along with the glial cells that give them structural and metabolic support. The nervous system is made up of the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, which includes the autonomic and somatic nervous systems. In vertebrates, the majority of neurons belong to the central nervous system, but some reside in peripheral ganglia, and many sensory neurons are situated in sensory organs such as the retina and cochlea.
Nervous system:
Axons may bundle into fascicles that make up the nerves in the peripheral nervous system (like strands of wire make up cables). Bundles of axons in the central nervous system are called tracts.
Anatomy and histology:
Neurons are highly specialized for the processing and transmission of cellular signals. Given their diversity of functions performed in different parts of the nervous system, there is a wide variety in their shape, size, and electrochemical properties. For instance, the soma of a neuron can vary from 4 to 100 micrometers in diameter.
The soma is the body of the neuron. As it contains the nucleus, most protein synthesis occurs here. The nucleus can range from 3 to 18 micrometers in diameter.
The dendrites of a neuron are cellular extensions with many branches. This overall shape and structure are referred to metaphorically as a dendritic tree. This is where the majority of input to the neuron occurs via the dendritic spine.
Anatomy and histology:
The axon is a finer, cable-like projection that can extend tens, hundreds, or even tens of thousands of times the diameter of the soma in length. The axon primarily carries nerve signals away from the soma and carries some types of information back to it. Many neurons have only one axon, but this axon may—and usually will—undergo extensive branching, enabling communication with many target cells. The part of the axon where it emerges from the soma is called the axon hillock. Besides being an anatomical structure, the axon hillock also has the greatest density of voltage-dependent sodium channels. This makes it the most easily excited part of the neuron and the spike initiation zone for the axon. In electrophysiological terms, it has the most negative threshold potential.
Anatomy and histology:
While the axon and axon hillock are generally involved in information outflow, this region can also receive input from other neurons.
Anatomy and histology:
The axon terminal is found at the end of the axon farthest from the soma and contains synapses. Synaptic boutons are specialized structures where neurotransmitter chemicals are released to communicate with target neurons. In addition to synaptic boutons at the axon terminal, a neuron may have en passant boutons, which are located along the length of the axon.The accepted view of the neuron attributes dedicated functions to its various anatomical components; however, dendrites and axons often act in ways contrary to their so-called main function.
Anatomy and histology:
Axons and dendrites in the central nervous system are typically only about one micrometer thick, while some in the peripheral nervous system are much thicker. The soma is usually about 10–25 micrometers in diameter and often is not much larger than the cell nucleus it contains. The longest axon of a human motor neuron can be over a meter long, reaching from the base of the spine to the toes.
Anatomy and histology:
Sensory neurons can have axons that run from the toes to the posterior column of the spinal cord, over 1.5 meters in adults. Giraffes have single axons several meters in length running along the entire length of their necks. Much of what is known about axonal function comes from studying the squid giant axon, an ideal experimental preparation because of its relatively immense size (0.5–1 millimeter thick, several centimeters long).
Anatomy and histology:
Fully differentiated neurons are permanently postmitotic however, stem cells present in the adult brain may regenerate functional neurons throughout the life of an organism (see neurogenesis). Astrocytes are star-shaped glial cells. They have been observed to turn into neurons by virtue of their stem cell-like characteristic of pluripotency.
Anatomy and histology:
Membrane Like all animal cells, the cell body of every neuron is enclosed by a plasma membrane, a bilayer of lipid molecules with many types of protein structures embedded in it. A lipid bilayer is a powerful electrical insulator, but in neurons, many of the protein structures embedded in the membrane are electrically active. These include ion channels that permit electrically charged ions to flow across the membrane and ion pumps that chemically transport ions from one side of the membrane to the other. Most ion channels are permeable only to specific types of ions. Some ion channels are voltage gated, meaning that they can be switched between open and closed states by altering the voltage difference across the membrane. Others are chemically gated, meaning that they can be switched between open and closed states by interactions with chemicals that diffuse through the extracellular fluid. The ion materials include sodium, potassium, chloride, and calcium. The interactions between ion channels and ion pumps produce a voltage difference across the membrane, typically a bit less than 1/10 of a volt at baseline. This voltage has two functions: first, it provides a power source for an assortment of voltage-dependent protein machinery that is embedded in the membrane; second, it provides a basis for electrical signal transmission between different parts of the membrane.
Anatomy and histology:
Histology and internal structure Numerous microscopic clumps called Nissl bodies (or Nissl substance) are seen when nerve cell bodies are stained with a basophilic ("base-loving") dye. These structures consist of rough endoplasmic reticulum and associated ribosomal RNA. Named after German psychiatrist and neuropathologist Franz Nissl (1860–1919), they are involved in protein synthesis and their prominence can be explained by the fact that nerve cells are very metabolically active. Basophilic dyes such as aniline or (weakly) haematoxylin highlight negatively charged components, and so bind to the phosphate backbone of the ribosomal RNA.
Anatomy and histology:
The cell body of a neuron is supported by a complex mesh of structural proteins called neurofilaments, which together with neurotubules (neuronal microtubules) are assembled into larger neurofibrils. Some neurons also contain pigment granules, such as neuromelanin (a brownish-black pigment that is byproduct of synthesis of catecholamines), and lipofuscin (a yellowish-brown pigment), both of which accumulate with age. Other structural proteins that are important for neuronal function are actin and the tubulin of microtubules. Class III β-tubulin is found almost exclusively in neurons. Actin is predominately found at the tips of axons and dendrites during neuronal development. There the actin dynamics can be modulated via an interplay with microtubule.There are different internal structural characteristics between axons and dendrites. Typical axons almost never contain ribosomes, except some in the initial segment. Dendrites contain granular endoplasmic reticulum or ribosomes, in diminishing amounts as the distance from the cell body increases.
Classification:
Neurons vary in shape and size and can be classified by their morphology and function. The anatomist Camillo Golgi grouped neurons into two types; type I with long axons used to move signals over long distances and type II with short axons, which can often be confused with dendrites. Type I cells can be further classified by the location of the soma. The basic morphology of type I neurons, represented by spinal motor neurons, consists of a cell body called the soma and a long thin axon covered by a myelin sheath. The dendritic tree wraps around the cell body and receives signals from other neurons. The end of the axon has branching axon terminals that release neurotransmitters into a gap called the synaptic cleft between the terminals and the dendrites of the next neuron.
Classification:
Structural classification Polarity Most neurons can be anatomically characterized as: Unipolar: single process. Unipolar cells are exclusively sensory neurons. Their dendrites are receiving sensory information, sometimes directly from the stimulus itself. The cell bodies of unipolar neurons are always found in ganglia. Sensory reception is a peripheral function, so the cell body is in the periphery, though closer to the CNS in a ganglion. The axon projects from the dendrite endings, past the cell body in a ganglion, and into the central nervous system.
Classification:
Bipolar: 1 axon and 1 dendrite. They are found mainly in the olfactory epithelium, and as part of the retina.
Classification:
Multipolar: 1 axon and 2 or more dendrites Golgi I: neurons with long-projecting axonal processes; examples are pyramidal cells, Purkinje cells, and anterior horn cells Golgi II: neurons whose axonal process projects locally; the best example is the granule cell Anaxonic: where the axon cannot be distinguished from the dendrite(s) Pseudounipolar: 1 process which then serves as both an axon and a dendrite Other Some unique neuronal types can be identified according to their location in the nervous system and distinct shape. Some examples are: Basket cells, interneurons that form a dense plexus of terminals around the soma of target cells, found in the cortex and cerebellum Betz cells, large motor neurons Lugaro cells, interneurons of the cerebellum Medium spiny neurons, most neurons in the corpus striatum Purkinje cells, huge neurons in the cerebellum, a type of Golgi I multipolar neuron Pyramidal cells, neurons with triangular soma, a type of Golgi I Rosehip cells, unique human inhibitory neurons that interconnect with Pyramidal cells Renshaw cells, neurons with both ends linked to alpha motor neurons Unipolar brush cells, interneurons with unique dendrite ending in a brush-like tuft Granule cells, a type of Golgi II neuron Anterior horn cells, motoneurons located in the spinal cord Spindle cells, interneurons that connect widely separated areas of the brain Functional classification Direction Afferent neurons convey information from tissues and organs into the central nervous system and are also called sensory neurons.
Classification:
Efferent neurons (motor neurons) transmit signals from the central nervous system to the effector cells.
Interneurons connect neurons within specific regions of the central nervous system.Afferent and efferent also refer generally to neurons that, respectively, bring information to or send information from the brain.
Classification:
Action on other neurons A neuron affects other neurons by releasing a neurotransmitter that binds to chemical receptors. The effect upon the postsynaptic neuron is determined by the type of receptor that is activated, not by the presynaptic neuron or by the neurotransmitter. A neurotransmitter can be thought of as a key, and a receptor as a lock: the same neurotransmitter can activate multiple types of receptors. Receptors can be classified broadly as excitatory (causing an increase in firing rate), inhibitory (causing a decrease in firing rate), or modulatory (causing long-lasting effects not directly related to firing rate).The two most common (90%+) neurotransmitters in the brain, glutamate and GABA, have largely consistent actions. Glutamate acts on several types of receptors, and has effects that are excitatory at ionotropic receptors and a modulatory effect at metabotropic receptors. Similarly, GABA acts on several types of receptors, but all of them have inhibitory effects (in adult animals, at least). Because of this consistency, it is common for neuroscientists to refer to cells that release glutamate as "excitatory neurons", and cells that release GABA as "inhibitory neurons". Some other types of neurons have consistent effects, for example, "excitatory" motor neurons in the spinal cord that release acetylcholine, and "inhibitory" spinal neurons that release glycine.The distinction between excitatory and inhibitory neurotransmitters is not absolute. Rather, it depends on the class of chemical receptors present on the postsynaptic neuron. In principle, a single neuron, releasing a single neurotransmitter, can have excitatory effects on some targets, inhibitory effects on others, and modulatory effects on others still. For example, photoreceptor cells in the retina constantly release the neurotransmitter glutamate in the absence of light. So-called OFF bipolar cells are, like most neurons, excited by the released glutamate. However, neighboring target neurons called ON bipolar cells are instead inhibited by glutamate, because they lack typical ionotropic glutamate receptors and instead express a class of inhibitory metabotropic glutamate receptors. When light is present, the photoreceptors cease releasing glutamate, which relieves the ON bipolar cells from inhibition, activating them; this simultaneously removes the excitation from the OFF bipolar cells, silencing them.It is possible to identify the type of inhibitory effect a presynaptic neuron will have on a postsynaptic neuron, based on the proteins the presynaptic neuron expresses. Parvalbumin-expressing neurons typically dampen the output signal of the postsynaptic neuron in the visual cortex, whereas somatostatin-expressing neurons typically block dendritic inputs to the postsynaptic neuron.
Classification:
Discharge patterns Neurons have intrinsic electroresponsive properties like intrinsic transmembrane voltage oscillatory patterns. So neurons can be classified according to their electrophysiological characteristics: Tonic or regular spiking. Some neurons are typically constantly (tonically) active, typically firing at a constant frequency. Example: interneurons in neurostriatum.
Phasic or bursting. Neurons that fire in bursts are called phasic.
Fast spiking. Some neurons are notable for their high firing rates, for example some types of cortical inhibitory interneurons, cells in globus pallidus, retinal ganglion cells.
Neurotransmitter Neurotransmitters are chemical messengers passed from one neuron to another neuron or to a muscle cell or gland cell.
Classification:
Cholinergic neurons – acetylcholine. Acetylcholine is released from presynaptic neurons into the synaptic cleft. It acts as a ligand for both ligand-gated ion channels and metabotropic (GPCRs) muscarinic receptors. Nicotinic receptors are pentameric ligand-gated ion channels composed of alpha and beta subunits that bind nicotine. Ligand binding opens the channel causing influx of Na+ depolarization and increases the probability of presynaptic neurotransmitter release. Acetylcholine is synthesized from choline and acetyl coenzyme A.
Classification:
Adrenergic neurons – noradrenaline. Noradrenaline (norepinephrine) is released from most postganglionic neurons in the sympathetic nervous system onto two sets of GPCRs: alpha adrenoceptors and beta adrenoceptors. Noradrenaline is one of the three common catecholamine neurotransmitter, and the most prevalent of them in the peripheral nervous system; as with other catecholamines, it is synthesised from tyrosine.
Classification:
GABAergic neurons – gamma aminobutyric acid. GABA is one of two neuroinhibitors in the central nervous system (CNS), along with glycine. GABA has a homologous function to ACh, gating anion channels that allow Cl− ions to enter the post synaptic neuron. Cl− causes hyperpolarization within the neuron, decreasing the probability of an action potential firing as the voltage becomes more negative (for an action potential to fire, a positive voltage threshold must be reached). GABA is synthesized from glutamate neurotransmitters by the enzyme glutamate decarboxylase.
Classification:
Glutamatergic neurons – glutamate. Glutamate is one of two primary excitatory amino acid neurotransmitters, along with aspartate. Glutamate receptors are one of four categories, three of which are ligand-gated ion channels and one of which is a G-protein coupled receptor (often referred to as GPCR).AMPA and Kainate receptors function as cation channels permeable to Na+ cation channels mediating fast excitatory synaptic transmission.
Classification:
NMDA receptors are another cation channel that is more permeable to Ca2+. The function of NMDA receptors depend on glycine receptor binding as a co-agonist within the channel pore. NMDA receptors do not function without both ligands present.
Classification:
Metabotropic receptors, GPCRs modulate synaptic transmission and postsynaptic excitability.Glutamate can cause excitotoxicity when blood flow to the brain is interrupted, resulting in brain damage. When blood flow is suppressed, glutamate is released from presynaptic neurons, causing greater NMDA and AMPA receptor activation than normal outside of stress conditions, leading to elevated Ca2+ and Na+ entering the post synaptic neuron and cell damage. Glutamate is synthesized from the amino acid glutamine by the enzyme glutamate synthase.Dopaminergic neurons—dopamine. Dopamine is a neurotransmitter that acts on D1 type (D1 and D5) Gs-coupled receptors, which increase cAMP and PKA, and D2 type (D2, D3, and D4) receptors, which activate Gi-coupled receptors that decrease cAMP and PKA. Dopamine is connected to mood and behavior and modulates both pre- and post-synaptic neurotransmission. Loss of dopamine neurons in the substantia nigra has been linked to Parkinson's disease. Dopamine is synthesized from the amino acid tyrosine. Tyrosine is catalyzed into levodopa (or L-DOPA) by tyrosine hydroxlase, and levodopa is then converted into dopamine by the aromatic amino acid decarboxylase.
Classification:
Serotonergic neurons—serotonin. Serotonin (5-Hydroxytryptamine, 5-HT) can act as excitatory or inhibitory. Of its four 5-HT receptor classes, 3 are GPCR and 1 is a ligand-gated cation channel. Serotonin is synthesized from tryptophan by tryptophan hydroxylase, and then further by decarboxylase. A lack of 5-HT at postsynaptic neurons has been linked to depression. Drugs that block the presynaptic serotonin transporter are used for treatment, such as Prozac and Zoloft.
Classification:
Purinergic neurons—ATP. ATP is a neurotransmitter acting at both ligand-gated ion channels (P2X receptors) and GPCRs (P2Y) receptors. ATP is, however, best known as a cotransmitter. Such purinergic signalling can also be mediated by other purines like adenosine, which particularly acts at P2Y receptors.
Histaminergic neurons—histamine. Histamine is a monoamine neurotransmitter and neuromodulator. Histamine-producing neurons are found in the tuberomammillary nucleus of the hypothalamus. Histamine is involved in arousal and regulating sleep/wake behaviors.
Classification:
Multimodel classification Since 2012 there has been a push from the cellular and computational neuroscience community to come up with a universal classification of neurons that will apply to all neurons in the brain as well as across species. This is done by considering the three essential qualities of all neurons: electrophysiology, morphology, and the individual transcriptome of the cells. Besides being universal this classification has the advantage of being able to classify astrocytes as well. A method called Patch-Seq in which all three qualities can be measured at once is used extensively by the Allen Institute for Brain Science.
Connectivity:
Neurons communicate with each other via synapses, where either the axon terminal of one cell contacts another neuron's dendrite, soma or, less commonly, axon. Neurons such as Purkinje cells in the cerebellum can have over 1000 dendritic branches, making connections with tens of thousands of other cells; other neurons, such as the magnocellular neurons of the supraoptic nucleus, have only one or two dendrites, each of which receives thousands of synapses.
Connectivity:
Synapses can be excitatory or inhibitory, either increasing or decreasing activity in the target neuron, respectively. Some neurons also communicate via electrical synapses, which are direct, electrically conductive junctions between cells.When an action potential reaches the axon terminal, it opens voltage-gated calcium channels, allowing calcium ions to enter the terminal. Calcium causes synaptic vesicles filled with neurotransmitter molecules to fuse with the membrane, releasing their contents into the synaptic cleft. The neurotransmitters diffuse across the synaptic cleft and activate receptors on the postsynaptic neuron. High cytosolic calcium in the axon terminal triggers mitochondrial calcium uptake, which, in turn, activates mitochondrial energy metabolism to produce ATP to support continuous neurotransmission.An autapse is a synapse in which a neuron's axon connects to its own dendrites.
Connectivity:
The human brain has some 8.6 x 1010 (eighty six billion) neurons. Each neuron has on average 7,000 synaptic connections to other neurons. It has been estimated that the brain of a three-year-old child has about 1015 synapses (1 quadrillion). This number declines with age, stabilizing by adulthood. Estimates vary for an adult, ranging from 1014 to 5 x 1014 synapses (100 to 500 trillion).
Connectivity:
Nonelectrochemical signaling Beyond electrical and chemical signaling, studies suggest neurons in healthy human brains can also communicate through: force generated by the enlargement of dendritic spines the transfer of proteins – transneuronally transported proteins (TNTPs)They can also get modulated by input from the environment and hormones released from other parts of the organism, which could be influenced more or less directly by neurons. This also applies to neurotrophins such as BDNF. The gut microbiome is also connected with the brain.
Connectivity:
Neurons also communicate with microglia, the brain's main immune cells via specialised contact sites, called "somatic junctions". These connections enable microglia to constantly monitor and regulate neuronal functions, and exert neuroprotection, when needed.
Mechanisms for propagating action potentials:
In 1937 John Zachary Young suggested that the squid giant axon could be used to study neuronal electrical properties. It is larger than but similar to human neurons, making it easier to study. By inserting electrodes into the squid giant axons, accurate measurements were made of the membrane potential.
The cell membrane of the axon and soma contain voltage-gated ion channels that allow the neuron to generate and propagate an electrical signal (an action potential). Some neurons also generate subthreshold membrane potential oscillations. These signals are generated and propagated by charge-carrying ions including sodium (Na+), potassium (K+), chloride (Cl−), and calcium (Ca2+).
Mechanisms for propagating action potentials:
Several stimuli can activate a neuron leading to electrical activity, including pressure, stretch, chemical transmitters, and changes of the electric potential across the cell membrane. Stimuli cause specific ion-channels within the cell membrane to open, leading to a flow of ions through the cell membrane, changing the membrane potential. Neurons must maintain the specific electrical properties that define their neuron type.Thin neurons and axons require less metabolic expense to produce and carry action potentials, but thicker axons convey impulses more rapidly. To minimize metabolic expense while maintaining rapid conduction, many neurons have insulating sheaths of myelin around their axons. The sheaths are formed by glial cells: oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system. The sheath enables action potentials to travel faster than in unmyelinated axons of the same diameter, whilst using less energy. The myelin sheath in peripheral nerves normally runs along the axon in sections about 1 mm long, punctuated by unsheathed nodes of Ranvier, which contain a high density of voltage-gated ion channels. Multiple sclerosis is a neurological disorder that results from demyelination of axons in the central nervous system.
Mechanisms for propagating action potentials:
Some neurons do not generate action potentials, but instead generate a graded electrical signal, which in turn causes graded neurotransmitter release. Such non-spiking neurons tend to be sensory neurons or interneurons, because they cannot carry signals long distances.
Neural coding:
Neural coding is concerned with how sensory and other information is represented in the brain by neurons. The main goal of studying neural coding is to characterize the relationship between the stimulus and the individual or ensemble neuronal responses, and the relationships among the electrical activities of the neurons within the ensemble. It is thought that neurons can encode both digital and analog information.
All-or-none principle:
The conduction of nerve impulses is an example of an all-or-none response. In other words, if a neuron responds at all, then it must respond completely. Greater intensity of stimulation, like brighter image/louder sound, does not produce a stronger signal, but can increase firing frequency.: 31 Receptors respond in different ways to stimuli. Slowly adapting or tonic receptors respond to steady stimulus and produce a steady rate of firing. Tonic receptors most often respond to increased intensity of stimulus by increasing their firing frequency, usually as a power function of stimulus plotted against impulses per second. This can be likened to an intrinsic property of light where greater intensity of a specific frequency (color) requires more photons, as the photons can not become "stronger" for a specific frequency.
All-or-none principle:
Other receptor types include quickly adapting or phasic receptors, where firing decreases or stops with steady stimulus; examples include skin which, when touched causes neurons to fire, but if the object maintains even pressure, the neurons stop firing. The neurons of the skin and muscles that are responsive to pressure and vibration have filtering accessory structures that aid their function.
All-or-none principle:
The pacinian corpuscle is one such structure. It has concentric layers like an onion, which form around the axon terminal. When pressure is applied and the corpuscle is deformed, mechanical stimulus is transferred to the axon, which fires. If the pressure is steady, stimulus ends; thus, typically these neurons respond with a transient depolarization during the initial deformation and again when the pressure is removed, which causes the corpuscle to change shape again. Other types of adaptation are important in extending the function of a number of other neurons.
Etymology and spelling:
The German anatomist Heinrich Wilhelm Waldeyer introduced the term neuron in 1891, based on the ancient Greek νεῦρον neuron 'sinew, cord, nerve'.The word was adopted in French with the spelling neurone. That spelling was also used by many writers in English, but has now become rare in American usage and uncommon in British usage.
History:
The neuron's place as the primary functional unit of the nervous system was first recognized in the late 19th century through the work of the Spanish anatomist Santiago Ramón y Cajal.To make the structure of individual neurons visible, Ramón y Cajal improved a silver staining process that had been developed by Camillo Golgi. The improved process involves a technique called "double impregnation" and is still in use.
History:
In 1888 Ramón y Cajal published a paper about the bird cerebellum. In this paper, he stated that he could not find evidence for anastomosis between axons and dendrites and called each nervous element "an absolutely autonomous canton." This became known as the neuron doctrine, one of the central tenets of modern neuroscience.In 1891, the German anatomist Heinrich Wilhelm Waldeyer wrote a highly influential review of the neuron doctrine in which he introduced the term neuron to describe the anatomical and physiological unit of the nervous system.The silver impregnation stains are a useful method for neuroanatomical investigations because, for reasons unknown, it stains only a small percentage of cells in a tissue, exposing the complete micro structure of individual neurons without much overlap from other cells.
History:
Neuron doctrine The neuron doctrine is the now fundamental idea that neurons are the basic structural and functional units of the nervous system. The theory was put forward by Santiago Ramón y Cajal in the late 19th century. It held that neurons are discrete cells (not connected in a meshwork), acting as metabolically distinct units.
History:
Later discoveries yielded refinements to the doctrine. For example, glial cells, which are non-neuronal, play an essential role in information processing. Also, electrical synapses are more common than previously thought, comprising direct, cytoplasmic connections between neurons. In fact, neurons can form even tighter couplings: the squid giant axon arises from the fusion of multiple axons.Ramón y Cajal also postulated the Law of Dynamic Polarization, which states that a neuron receives signals at its dendrites and cell body and transmits them, as action potentials, along the axon in one direction: away from the cell body. The Law of Dynamic Polarization has important exceptions; dendrites can serve as synaptic output sites of neurons and axons can receive synaptic inputs.
History:
Compartmental modelling of neurons Although neurons are often described of as "fundamental units" of the brain, they perform internal computations. Neurons integrate input within dendrites, and this complexity is lost in models that assume neurons to be a fundamental unit. Dendritic branches can be modeled as spatial compartments, whose activity is related due to passive membrane properties, but may also be different depending on input from synapses. Compartmental modelling of dendrites is especially helpful for understanding the behavior of neurons that are too small to record with electrodes, as is the case for Drosophila melanogaster.
Neurons in the brain:
The number of neurons in the brain varies dramatically from species to species. In a human, there are an estimated 10–20 billion neurons in the cerebral cortex and 55–70 billion neurons in the cerebellum. By contrast, the nematode worm Caenorhabditis elegans has just 302 neurons, making it an ideal model organism as scientists have been able to map all of its neurons. The fruit fly Drosophila melanogaster, a common subject in biological experiments, has around 100,000 neurons and exhibits many complex behaviors. Many properties of neurons, from the type of neurotransmitters used to ion channel composition, are maintained across species, allowing scientists to study processes occurring in more complex organisms in much simpler experimental systems.
Neurological disorders:
Charcot–Marie–Tooth disease (CMT) is a heterogeneous inherited disorder of nerves (neuropathy) that is characterized by loss of muscle tissue and touch sensation, predominantly in the feet and legs extending to the hands and arms in advanced stages. Presently incurable, this disease is one of the most common inherited neurological disorders, affecting 36 in 100,000 people.Alzheimer's disease (AD), also known simply as Alzheimer's, is a neurodegenerative disease characterized by progressive cognitive deterioration, together with declining activities of daily living and neuropsychiatric symptoms or behavioral changes. The most striking early symptom is loss of short-term memory (amnesia), which usually manifests as minor forgetfulness that becomes steadily more pronounced with illness progression, with relative preservation of older memories. As the disorder progresses, cognitive (intellectual) impairment extends to the domains of language (aphasia), skilled movements (apraxia), and recognition (agnosia), and functions such as decision-making and planning become impaired.Parkinson's disease (PD), also known as Parkinsons, is a degenerative disorder of the central nervous system that often impairs motor skills and speech. Parkinson's disease belongs to a group of conditions called movement disorders. It is characterized by muscle rigidity, tremor, a slowing of physical movement (bradykinesia), and in extreme cases, a loss of physical movement (akinesia). The primary symptoms are the results of decreased stimulation of the motor cortex by the basal ganglia, normally caused by the insufficient formation and action of dopamine, which is produced in the dopaminergic neurons of the brain. Secondary symptoms may include high level cognitive dysfunction and subtle language problems. PD is both chronic and progressive.
Neurological disorders:
Myasthenia gravis is a neuromuscular disease leading to fluctuating muscle weakness and fatigability during simple activities. Weakness is typically caused by circulating antibodies that block acetylcholine receptors at the post-synaptic neuromuscular junction, inhibiting the stimulative effect of the neurotransmitter acetylcholine. Myasthenia is treated with immunosuppressants, cholinesterase inhibitors and, in selected cases, thymectomy.
Demyelination Demyelination is the act of demyelinating, or the loss of the myelin sheath insulating the nerves. When myelin degrades, conduction of signals along the nerve can be impaired or lost, and the nerve eventually withers. This leads to certain neurodegenerative disorders like multiple sclerosis and chronic inflammatory demyelinating polyneuropathy.
Neurological disorders:
Axonal degeneration Although most injury responses include a calcium influx signaling to promote resealing of severed parts, axonal injuries initially lead to acute axonal degeneration, which is the rapid separation of the proximal and distal ends, occurring within 30 minutes of injury. Degeneration follows with swelling of the axolemma, and eventually leads to bead-like formation. Granular disintegration of the axonal cytoskeleton and inner organelles occurs after axolemma degradation. Early changes include accumulation of mitochondria in the paranodal regions at the site of injury. Endoplasmic reticulum degrades and mitochondria swell up and eventually disintegrate. The disintegration is dependent on ubiquitin and calpain proteases (caused by the influx of calcium ion), suggesting that axonal degeneration is an active process that produces complete fragmentation. The process takes about roughly 24 hours in the PNS and longer in the CNS. The signaling pathways leading to axolemma degeneration are unknown.
Neurogenesis:
Neurons are born through the process of neurogenesis, in which neural stem cells divide to produce differentiated neurons. Once fully differentiated neurons are formed, they are no longer capable of undergoing mitosis. Neurogenesis primarily occurs in the embryo of most organisms.
Neurogenesis:
Adult neurogenesis can occur and studies of the age of human neurons suggest that this process occurs only for a minority of cells, and that the vast majority of neurons in the neocortex forms before birth and persists without replacement. The extent to which adult neurogenesis exists in humans, and its contribution to cognition are controversial, with conflicting reports published in 2018.The body contains a variety of stem cell types that have the capacity to differentiate into neurons. Researchers found a way to transform human skin cells into nerve cells using transdifferentiation, in which "cells are forced to adopt new identities".During neurogenesis in the mammalian brain, progenitor and stem cells progress from proliferative divisions to differentiative divisions. This progression leads to the neurons and glia that populate cortical layers. Epigenetic modifications play a key role in regulating gene expression in differentiating neural stem cells, and are critical for cell fate determination in the developing and adult mammalian brain. Epigenetic modifications include DNA cytosine methylation to form 5-methylcytosine and 5-methylcytosine demethylation. These modifications are critical for cell fate determination in the developing and adult mammalian brain. DNA cytosine methylation is catalyzed by DNA methyltransferases (DNMTs). Methylcytosine demethylation is catalyzed in several stages by TET enzymes that carry out oxidative reactions (e.g. 5-methylcytosine to 5-hydroxymethylcytosine) and enzymes of the DNA base excision repair (BER) pathway.At different stages of mammalian nervous system development two DNA repair processes are employed in the repair of DNA double-strand breaks. These pathways are homologous recombinational repair used in proliferating neural precursor cells, and non-homologous end joining used mainly at later developmental stagesIntercellular communication between developing neurons and microglia is also indispensable for proper neurogenesis and brain development.
Nerve regeneration:
Peripheral axons can regrow if they are severed, but one neuron cannot be functionally replaced by one of another type (Llinás' law). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Horse colic**
Horse colic:
Colic in horses is defined as abdominal pain, but it is a clinical symptom rather than a diagnosis. The term colic can encompass all forms of gastrointestinal conditions which cause pain as well as other causes of abdominal pain not involving the gastrointestinal tract. What makes it tricky is that different causes can manifest with similar signs of distress in the animal. Recognizing and understanding these signs is pivotal, as timely action can spell the difference between a brief moment of discomfort and a life-threatening situation. The most common forms of colic are gastrointestinal in nature and are most often related to colonic disturbance. There are a variety of different causes of colic, some of which can prove fatal without surgical intervention. Colic surgery is usually an expensive procedure as it is major abdominal surgery, often with intensive aftercare. Among domesticated horses, colic is the leading cause of premature death. The incidence of colic in the general horse population has been estimated between 4 and 10 percent over the course of the average lifespan. Clinical signs of colic generally require treatment by a veterinarian. The conditions that cause colic can become life-threatening in a short period of time.
Pathophysiology:
Colic can be divided broadly into several categories: excessive gas accumulation in the intestine (gas colic) simple obstruction strangulating obstruction non-strangulating infarction inflammation of the gastrointestinal tract (enteritis, colitis) or the peritoneum (peritonitis) ulceration of the gastrointestinal mucosaThese categories can be further differentiated based on location of the lesion and underlying cause (See Types of colic).
Pathophysiology:
Simple obstruction This is characterised by a physical obstruction of the intestine, which can be due to impacted food material, stricture formation, or foreign bodies. The primary pathophysiological abnormality caused by this obstruction is related to the trapping of fluid within the intestine oral to the obstruction. This is due to the large amount of fluid produced in the upper gastrointestinal tract, and the fact that this is primarily re-absorbed in parts of the intestine downstream from the obstruction. The first problem with this degree of fluid loss from circulation is one of decreased plasma volume, leading to reduced cardiac output, and acid-base disturbances.
Pathophysiology:
The intestine becomes distended due to the trapped fluid and gas production from bacteria. It is this distension, and subsequent activation of stretch receptors within the intestinal wall, that leads to the associated pain. With progressive distension of the intestinal wall, there is occlusion of blood vessels, firstly the less rigid veins, then arteries. This impairment of blood supply leads to hyperemia and congestion, and ultimately to ischaemic necrosis and cellular death. The poor blood supply also has effects on the vascular endothelium, leading to an increased permeability which first leaks plasma and eventually blood into the intestinal lumen. In the opposite fashion, gram-negative bacteria and endotoxins can enter the bloodstream, leading to further systemic effects.
Pathophysiology:
Strangulating obstruction Strangulating obstructions have all the same pathological features as a simple obstruction, but the blood supply is immediately affected. Both arteries and veins may be affected immediately, or progressively as in simple obstruction. Common causes of strangulating obstruction are intussusceptions, torsion or volvulus, and displacement of intestine through a hole, such as a hernia, a mesenteric rent, or the epiploic foramen.
Pathophysiology:
Non-strangulating infarction In a non-strangulating infarction, blood supply to a section of intestine is occluded, without any obstruction to ingesta present within the intestinal lumen. The most common cause is infection with Strongylus vulgaris larvae, which primarily develop within the cranial mesenteric artery.
Pathophysiology:
Inflammation or ulceration of the gastrointestinal tract Inflammation along any portion of the GI tract can lead to colic. This leads to pain and possibly stasis of peristalsis (Ileus), which can cause excessive accumulation of fluid in the gastrointestinal tract. This is a functional rather than mechanical blockage of the intestine, but like the mechanical blockage seen with simple obstructions, it can have serious effects including severe dehydration. Inflammation of the bowel may lead to increased permeability and subsequent endotoxemia. The underlying cause of inflammation may be due to infection, toxin, or trauma, and may require special treatment in order to resolve the colic.
Pathophysiology:
Ulceration of the mucosal surface occurs very commonly in the stomach (gastric ulceration), due to damage from stomach acid or alteration in protective mechanisms of the stomach, and is usually not life-threatening. The right dorsal colon may also develop ulceration, usually secondary to excessive NSAID use, which alters the homeostatic balance of prostaglandins that protect the mucosa.
Types:
This list of types of colic is not exhaustive but details some of the types which may be encountered.
Types:
Gas and spasmodic colic Gas colic, also known as tympanic colic, is the result of gas buildup within the horse's digestive tract due to excessive fermentation within the intestines or a decreased ability to move gas through it. It is usually the result of a change in diet, but can also occur due to low dietary roughage levels, parasites (22% of spasmodic colics are associated with tapeworms), and anthelminthic administration. This gas buildup causes distention and increases pressure in the intestines, causing pain. Additionally, it usually causes an increase in peristaltic waves, which can lead to painful spasms of the intestine, producing subsequent spasmodic colic. The clinical signs of these forms of colic are generally mild, transient, and respond well to spasmolytic medications, such as buscopan, and analgesics. Gas colics usually self-correct, but there is the risk of subsequent torsion (volvulus) or displacement of the bowel due to gas distention, which causes this affected piece of bowel to rise upward in the abdomen.Abdominal distention may occasionally be seen in adult horses in the flank region, if the cecum or large colon is affected. Foals, however, may show signs of gas within the small intestines with severe abdominal distention.
Types:
Impaction Pelvic flexure impaction This is caused by an impaction of food material (water, grass, hay, grain) at a part of the large bowel known as the pelvic flexure of the left colon where the intestine takes a 180 degree turn and narrows. Impaction generally responds well to medical treatment, usually requiring a few days of fluids and laxatives such as mineral oil, but more severe cases may not recover without surgery. If left untreated, severe impaction colic can be fatal. The most common cause is when the horse is on box rest and/or consumes large volumes of concentrated feed, or the horse has dental disease and is unable to masticate properly. This condition could be diagnosed on rectal examination by a veterinarian. Impactions are often associated with the winter months because horses do not drink as much water and eat drier material (hay instead of grass), producing drier intestinal contents that are more likely to get stuck.
Types:
Ileal impaction and ileal hypertrophy The ileum is the last part of the small intestine that ends in the cecum. Ileal impaction can be caused by obstruction of ingesta. Coastal Bermuda hay is associated with impactions in this most distal segment of the small intestine, although it is difficult to separate this risk factor from geographic location, since the southeastern United States has a higher prevalence of ileal impaction and also has regional access to coastal Bermuda hay. Other causes can be obstruction by ascarids (Parascaris equorum), usually occurring at 3–5 months of age right after deworming, and tapeworms (Anoplocephala perfoliata), which have been associated with up to 81% of ileal impactions (See Ascarids). Horses show intermittent colic, with moderate to severe signs and with time, distended small intestinal loops on rectal. Although most ileal impactions will sometimes pass without intervention, those present for 8–12 hours will cause fluid to back up, leading to gastric reflux, which is seen in approximately 50% of horses that require surgical intervention. Diagnosis is usually made based on clinical signs, presence of reflux, rectal exam, and ultrasound. Often the impaction can not be felt on rectal due to distended small intestinal loops that block the examiner. Those impactions that are unresponsive to medical management, which includes IV fluids and removal of reflux, may be treated using a single injection into the ileum with 1 liter of carboxymethylcellulose, and then massaging the ileum. This allows the impaction to be treated without actually cutting into the ileum. Prognosis for survival is good.Ileal hypertrophy occurs when the circular and longitudinal layers of the ileal intestinal wall hypertrophy, and can also occur with jejunal hypertrophy. The mucosa remains normal, so malabsorption is not expected to occur in this disease. Ileal hypertrophy may be idiopathic, with current theories for such cases including neural dysfunction within the intestinal wall secondary to parasite migration, and increased tone of the ileocecal valve which leads to hypertrophy of the ileum as it tries to push contents into the cecum. Hypertrophy may also occur secondary to obstruction, especially those that have had surgery for an obstruction that required an anastomosis. Hypertrophy gradually decreases the size of the lumen, resulting in intermittent colic, and in approximately 45% of cases includes weight loss of 1–6 month duration and anorexia. Although rectal examination may display a thickened ileal wall, usually the diagnosis is made at surgery, and an ileocecal or jejunocecal anastomosis is made to allow intestinal contents to bypass the affected area. If surgery and bypass is not performed, there is a risk of rupture, but prognosis is fair with surgical treatment.
Types:
Sand impaction This is most likely to occur in horses that graze sandy or heavily grazed pastures leaving only dirt to ingest. Foals, weanlings, and yearlings are most likely to ingest sand, and are therefore most commonly seen with sand colic. The term sand also encompasses dirt. The ingested sand or dirt most commonly accumulates in the pelvic flexure, but may also occur in the right dorsal colon and the cecum of the large intestines. The sand can cause colic signs similar to other impactions of the large colon, and often causes abdominal distention As the sand or dirt irritates the lining of the bowel it can cause diarrhea. The weight and abrasion of the sand or dirt causes the bowel wall to become inflamed and can cause a reduction in colonic motility and, in severe cases, leads to peritonitis.
Types:
Diagnosis is usually made by history, environmental conditions, auscultation of the ventral abdomen, radiographs, ultrasound, or fecal examination (See Diagnosis). Historically, medical treatment of the problem is with laxatives such as liquid paraffin or oil and psyllium husk. More recently veterinarians treat cases with specific synbiotic (pro and prebiotic) and psyllium combinations. Psyllium is the most effective medical treatment. It works by binding to the sand to help remove it, although multiple treatments may be required. Mineral oil is mostly ineffective since it floats on the surface of the impaction, rather than penetrating it. Horses with sand or dirt impaction are predisposed to Salmonella infection and other GI bacteria, so antibiotics are often added to help prevent infection. Medical management usually resolves the colic, but if improvement doesn't occur within a few hours then surgery must be performed to flush the colon of any sand, which procedure that has a 60–65% survival rate. Horses that are not treated, or treated too late after the onset of clinical signs, are at risk of death.Horses should not be fed directly on the ground in areas where sand, dirt and silt are prevalent, although small amounts of sand or dirt may still be ingested by grazing. Management to reduce sand intake and prophylactic treatments with sand removal products are recommended by most veterinarians. Such prophylaxis includes feeding a pelleted psyllium for one week every 4–5 weeks. Longer duration of treatment will result in gastrointestinal flora changes and the psyllium to be broken down and ineffective for sand clearance. Other methods include feeding the horse before turnout, and turning the horses out in the middle of the day so they are more likely to stand in the shade rather than graze.
Types:
Cecal impaction Only 5% of large intestinal impactions at referral hospital involve the cecum. Primary cecal impactions usually consist of dry feed material, with the horse slowly developing clinical signs over several days. Secondary cecal impactions may occur post-surgery, orthopedic or otherwise, and the cecum does not function properly. Horses usually show clinical signs 3–5 days post general anesthesia, including decreased appetite, decreased manure production, and gas in the cecum which can be auscultated. The cecum quickly distends due to fluid and gas accumulation, often leading to rupture within 24–48 hours if not corrected. This impaction may be missed since decreased manure production can be attributed secondarily to surgery, and often rupture occurs before severe signs of pain. Horses are most at risk for this type of impaction if surgery is greater than 1 hour in length, or if inadequate analgesia is provided postoperatively.Diagnosis is usually made by rectal palpation. Treatment includes fluid therapy and analgesics, but surgery is indicated if there is severe distention of the cecum or if medical therapy does not improve the situation. Surgery includes typhlotomy, and although cecal bypass has been performed in the past to prevent reoccurrence, a recent study suggests it is not necessary. Surgery has a good prognosis, although rupture can occur during surgical manipulation. The cause of cecal impactions are not known. Cecal impassion should be differentiated from large colon impaction via rectal, since cecal impaction has a high risk of rupture even before developing severe pain. Overall prognosis is 90%, regardless of medical or surgical treatment, but rupture does occur, often with no warning.
Types:
Gastric impaction Gastric impactions are relatively rare, and occur when food is not cleared at the appropriate rate. It is most commonly associated with ingestion of foods that swell after eating or feeds that are coarse (bedding or poor quality roughage), poor dental care, poor mastication, inadequate drinking, ingestion of a foreign object, and alterations in the normal function of the stomach. Persimmons, which form a sticky gel in the stomach, and haylage, have both been associated with it, as has wheat, barley, mesquite beans, and beet pulp. Horses usually show signs of mild colic that is chronic, unresponsive to analgesics, and may include signs such as dysphagia, ptyalism, bruxism, fever, and lethargy, although severe colic signs may occur. Signs of shock may be seen if gastric rupture has occurred. Usually, the impaction must be quite large before it presents symptoms, and may be diagnosed via gastroscopy or ultrasound, although rectal examinations are unhelpful. Persimmon impaction is treated with infusions of Coca-Cola. Other gastric impactions are often resolves with enteral fluids. Quick treatment generally produces a favorable prognosis.
Types:
Small colon impaction Small colon impactions represent a small number of colics in the horse, and are usually caused by obstruction from fecaliths, enteroliths, and meconium. Horses usually present with standard colic signs (pawing, flank watching, rolling) in 82% of horses, and occasionally with diarrhea (31%), anorexia (30%), straining (12%), and depression (11%), and rectal examination will reveal firm loops of small colon or actually palpable obstruction in the rectum. Impactions are most common in miniature horses, possibly because they do not masticate their feed as well, and during the fall and winter. Medical management includes the aggressive use of fluids, laxatives and lubricants, and enemas, as well as analgesics and anti-inflammatories. However, these impactions often require surgical intervention, and the surgeon will empty the colon either by enterotomy or by lubricants and massage. Surgical intervention usually results in longer recovery time at the hospital. Prognosis is very good, and horses treated with surgical treatment had a survival with return to athletic function rate of 91%, while 89% of the medically managed horses returned to previous use.
Types:
Large colon impaction Large colon impactions typically occur at the pelvic flexure and right dorsal colon, two areas where the lumen of the intestine narrows. Large colon impactions are most frequently seen in horses that have recently had a sudden decrease in exercise, such as after a musculoskeletal injury. They are also associated in the practice of twice daily feeding of grain meals, which causes a short-lived but significant secretion of fluid into the lumen of the intestine, resulting in a 15% decrease in plasma volume (hypovolemia of the circulatory system) and the subsequent activation of the renin–angiotensin–aldosterone system. Aldosterone secretion activates absorption of fluid from the colon, decreasing the water content of the ingesta and increasing risk of impaction. Amitraz has also been associated with large colon impaction, due to alterations in motility and retention of intestinal contents, which causes further absorption of water and dehydration of ingesta. Other possible factors include poor dental care, course roughage, dehydration, and limited exercise.Horses with a large colon impaction usually have mild signs that slowly get worse if the impaction does not resolve, and can produce severe signs. Diagnosis is often made by rectal palpation of the mass, although this is not always accurate since a portion of the colon is not palpable on rectal. Additional sections of intestines may be distended if there is fluid backup. Manure production decreases, and if passed, is usually firm, dry and mucus covered. Horses are treated with analgesics, fluid therapy, mineral oil, dactyl sodium sulfosuccinate (DSS), and/or epsom salts. Analgesics usually can control the abdominal discomfort, but may become less efficacious over time if the impaction does not resolve. Persistent impactions may require fluids administered both intravenously and orally via nasogastric tube, at a rate 2–4 times the maintenance for the animal. Feed is withheld. Horses that do not improve or become very painful, or those that have large amounts of gas distention, are recommended to undergo surgery to remove the impaction via enterotomy of the pelvic flexure. Approximately 95% of horses that undergo medical management, and 58% of surgical cases, survive.
Types:
Enteroliths and fecaliths Enteroliths in horses are round 'stones' of mineral deposits, usually of ammonium magnesium phosphate (struvite) but sometimes of magnesium vivainite and some amounts of sodium, potassium, sulfur and calcium, which develop within the horse's gastrointestinal tract. They can form around a piece of ingested foreign material, such as a small nidus of wire or sand (similar to how an oyster forms a pearl). When they move from their original site they can obstruct the intestine, usually in the right dorsal and transverse colon, but rarely in the small colon. They may also cause mucosal irritation or pain when they move within the gastrointestinal tract. Enteroliths are not a common cause of colic, but are known to have a higher prevalence in states with a sandy soil or an abundance of alfalfa hay is fed, such as California, a state where 28% of surgical colics are due to enteroliths. Alfalfa hay is thought to increase the risk due to the high protein content in the hay, which would likely elevate ammonia nitrogen levels within the intestine. They may be more common in horses with diets high in magnesium, and are also seen more often in Arabians, Morgans, American Saddlebreds, miniature horses, and donkeys, and usually occur in horses older than four years of age. Horses with enteroliths typically have chronic, low-grade, recurring colic signs, which may lead to acute colic and distention of the large colon after occlusion of the lumen occurs. These horse may also have had a history of passing enteroliths in their manure. Level of pain is related to the degree of luminal occlusion. Abdominal radiographs can confirm the diagnosis, but smaller enteroliths may not be visible. In rare instances, enteroliths may be palpated on rectal examination, usually if they are present in the small colon. Once a horse is diagnosed with colic due to an enterolith, surgery is necessary to remove it, usually by pelvic flexure enterotomy and sometimes an additional right dorsal colon enterotomy, and fully resolve the signs of colic. Horses will usually present a round enterolith if it is the only one present, while multiple enteroliths will usually have flat sides, a clue to the surgeon to look for more stones. The main risk of surgery is rupture of the colon (15% of cases), and 92% of horses that are recovered survive to at least one year from their surgery date.Fecaliths are hard formations of ingest that obstruct the GI tract, and may require surgery to resolve. These are most commonly seen in miniature horses, ponies, and foals.
Types:
Displacement A displacement occurs when a portion of the large colon—usually the pelvic flexure—moves to an abnormal location. There are four main displacements described in equine medicine: Left dorsal displacement (nephrosplenic entrapment): the pelvic flexure moves dorsally towards the nephrosplenic space. This space is found between the spleen, the left kidney, the nephrosplenic ligament (which runs between the spleen and kidney), and the body wall. In some cases, the bowel become entrapped over the nephrosplenic ligament. LDD accounts for 6-8% of all colics.
Types:
Right dorsal displacement: the colon moves between the cecum and body wall.
Types:
The pelvic flexure retroflexes towards the diaphragm The colon develops a 180-degree volvulus, which may or may not occlude the vasculature of the organ.The cause of displacement is not definitively known, but one explanation is that the bowel becomes abnormally distended with gas (from excessive fermentation of grain, a change in the microbiota secondary to antibiotic use, or a buildup of gas secondary to impaction) which results in a shift in the bowel to an abnormal position. Because much of the bowel is not anchored to the body wall, it is free to move out of position. Displacement is usually diagnosed using a combination of findings from the rectal exam and ultrasonography.
Types:
Many displacements (~96% of LDD, 64% of RDD) resolve with medical management that includes fluids (oral or intravenous) to rehydrate the horse and soften any impaction that may be present. Systemic analgesics, antispasmodics, and sedation are often used to keep the horse comfortable during this time. Horses with left dorsal displacement are sometimes treated with exercise and/or phenylephrine—a medication that causes contracture of the spleen and may allow the bowel to slip off the nephrosplenic ligament. At times anesthesia and a rolling procedure, in which the horse is placed in left lateral recumbency and rolled to right lateral recumbency while jostling, can also be used to try to shift the colon off of the nephrosplenic ligament. Displacements that do not respond to medical therapy require surgery, which generally has a very high success rate (80–95%).Reoccurrence can occur with all types of displacements: 42% of horses with RDD, 46% of horses with retroflexion, 21% of those with volvulus, and 8% of those with LDD had reoccurrence of colic. LDD may be prevented by closing the nephrosplenic space with sutures, although this does not prevent other types of displacements from occurring in that same horse.
Types:
Torsion and volvulus A volvulus is a twist along the axis of the mesentery, a torsion is a twist along the longitudinal axis of the intestine. Various parts of the horse's gastrointestinal tract may twist upon themselves. It is most likely to be either small intestine or part of the colon. Occlusion of the blood supply means that it is a painful condition causing rapid deterioration and requiring emergency surgery.
Types:
Volvulus of the large colon usually occurs where the mesentery attaches to the body wall, but may also occur at the diaphragmatic or sternal flexures, with rotations up to 720 degrees reported. It is most commonly seen in postpartum mares, usually presents with severe signs of colic that are refractory to analgesic administration, and horses often lie in dorsal recumbency. Abdominal distention is common due to strangulation and rapid engorgement of the intestine with gas, which then can lead to dyspnea as the growing bowel pushes against the diaphragm and prevents normal ventilation. Additionally, compression can place pressure on the caudal vena cava, leading to pooling of blood and hypovolemia. However, horses may not have a high heart rate, presumably due to increased vagal tone. Rectal palpation will demonstrate a severely gas distended colon, and the examiner may not be able to push beyond the brim of the pelvis due to the obstruction. The colon may be irreversibly damaged in as little as 3–4 hours from the initial time of the volvulus, so immediate surgical correction is required. The surgeon works to correct the volvulus and then removes any damaged colon. 95% of the colon may be resected, but often the volvulus damages more than this amount, requiring euthanasia. Plasma lactate levels can help predict survival rates, with an increased survival seen in horses with a lactate below 6.0 mmol/L. Prognosis is usually poor, with a survival rate of approximately 36% of horses with a 360 degree volvulus, and 74% of those with a 270 degree volvulus, and a reoccurrence rate of 5–50%. Complications post-surgery include hypoproteinemia, endotoxic shock, laminitis, and DIC.Small intestinal volvulus is thought to be caused by a change in local peristalsis, or due to a lesion that the mesentery may twist around (such as an ascarid impaction), and usually involves the distal jejunum and ileum.w It is one of the most common causes of small intestinal obstruction in foals, possibly because of a sudden change to a bulkier foodstuff. Animals present with acute and severe signs of colic, and multiple distended loops of small intestine, usually seen radiographically in a foal. Small intestinal volvulus often occurs secondary to another disease process in adult horses, where small intestinal obstruction causes distention and then rotation around the root of the mesentery. Surgery is required to resect nonviable sections of bowel, and prognosis is correlated to the length of bowel involved, with animals with greater than 50% of small intestinal involvement having a grave prognosis.
Types:
Intussusception Intussusception is a form of colic in which a piece of intestine "telescopes" within a portion of itself because a section is paralyzed, so the motile section pushes itself into the non-motile section. It most commonly occurs at the ileocecal junction and requires urgent surgery. It is almost always associated with parasitic infections, usually tapeworms, although small masses and foreign bodies may also be responsible, and is most common in young horses usually around 1 year of age. Ileocecal intussusception may be acute, involving longer (6–457 cm) segments of bowel, or chronic involving shorter sections (up to 10 cm in length). Horses with the acute form of colic usually have a duration of colic less than 24 hours long, while chronic cases have mild but intermittent colic. Horses with the chronic form tend to have better prognosis.
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Rectal examination reveals a mass at the base of the cecum in 50% of cases. Ultrasound reveals a very characteristic "target" pattern on cross-section. Abdominocentesis results can vary, since the strangulated bowel is trapped within the healthy bowel, but there are usually signs of obstruction, including reflux and multiple loops of distended small intestine felt on rectal. Surgery is required for intussusception. Reduction of the area is usually ineffective due to swelling, so jejunojejunal intussusceptions are resected and ileocolic intussusceptions are resected as far distally as possible and a jejunocecal anatomosis is performed.
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Entrapment Epiploic foramen entrapment On rare occasions, a piece of small intestine (or rarely colon) can become trapped through the epiploic foramen into the omental bursa. The blood supply to this piece of intestine is immediately occluded and surgery is the only available treatment. This type of colic has been associated with cribbers, possibly due to changes in abdominal pressure, and in older horses, possibly because the foramen enlarges as the right lobe of the liver atrophies with age, although it has been seen in horses as young as 4 months old. Horses usually present with colic signs referable to small intestinal obstruction. During surgery, the foramen can not be enlarged due to the risk of rupture of the vena cava or portal vein, which would result in fatal hemorrhage. Survival is 74–79%, and survival is consistently correlated with abdominocentesis findings prior to surgery.
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Mesenteric rent entrapment The mesentery is a thin sheet attached to the entire length of intestine, enclosing blood vessels, lymph nodes, and nerves. Occasionally, a small rent (hole) can form in the mesentery, through which a segment of bowel can occasionally enter. As in epiploic foramen entrapment, the bowel first enlarges, since arteries do not occlude as easily as veins, which causes edema (fluid buildup). As the bowel enlarges, it becomes less and less likely to be able to exit the site of entrapment. Colic signs are referable to those seen with a strangulating lesion, such as moderate to severe abdominal pain, endotoxemia, decrease gut sounds, distended small intestine on rectal, and nasogastric reflux. This problem requires surgical correction. Survival for mesenteric rent entrapment is usually lower than other small intestinal strangulating lesions, possibly due to hemorrhage, difficulty correcting the entrapment, and the length of intestine commonly involved, with <50% of cases surviving until discharge.
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Inflammatory and ulcerative conditions Proximal enteritis Proximal enteritis, also known as anterior enteritis or duodenitis-proximal jejunitis (DPJ), is inflammation of the duodenum and upper jejunum. It is potentially caused by infectious organisms, such as Salmonella and Clostridial species, but other possible contributing factors include Fusarium infection or high concentrate diets. The inflammation of the intestine leads to large secretions of electrolytes and fluid into its lumen, and thus large amounts of gastric reflux, leading to dehydration and occasionally shock.Signs include acute onset of moderate to severe pain, large volumes orange-brown and fetid gastric reflux, distended small intestine on rectal examination, fever, depression, increased heart rate and respiratory rate, prolonged CRT, and darkened mucous membranes. Pain level usually improves after gastric decompression. It is important to differentiate DPI from small intestinal obstruction, since obstruction may require surgical intervention. This can be difficult, and often requires a combination of clinical signs, results from the physical examination, laboratory data, and ultrasound to help suggest one diagnosis over the other, but a definitive diagnosis can only be made with surgery or on necropsy.DPI usually is managed medically with nasogastric intubation every 1–2 hours to relieve gastric pressure secondary to reflux, and aggressive fluid support to maintain hydration and correct electrolyte imbalances. Horses are often withheld food for several days. Use of anti-inflammatory, anti-endotoxin, anti-microbial, and prokinetic drugs are common with this disease. Surgery may be needed to rule out obstruction or strangulation, and in cases that are long-standing to perform a resection and anastomosis of the diseased bowel. Survival rates for DPJ are 25–94%, and horses in the southeast United States appear to be more severely affected.
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Colitis Colitis is inflammation of the colon. Acute cases are medical emergencies as the horse rapidly loses fluid, protein, and electrolytes into the gut, leading to severe dehydration which can result in hypovolemic shock and death. Horses generally present with signs of colic before developing profuse, watery, fetid diarrhea.
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Both infectious and non-infectious causes for colitis exist. In the adult horse, Salmonella, Clostridium difficile, and Neorickettsia risticii (the causative agent of Potomac Horse Fever) are common causes of colitis. Antibiotics, which may lead to an altered and unhealthy microbiota, sand, grain overload, and toxins such as arsenic and cantharidin can also lead to colitis. Unfortunately, only 20–30% of acute colitis cases are able to be definitively diagnosed. NSAIDs can cause slower-onset of colitis, usually in the right dorsal colon (see Right dorsal colitis).
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Treatment involves administration of large volumes of intravenous fluids, which can become very costly. Antibiotics are often given if deemed appropriate based on the presumed underlying cause and the horse's CBC results. Therapy to help prevent endotoxemia and improve blood protein levels (plasma or synthetic colloid administration) may also be used if budgetary constraints allow. Other therapies include probiotics and anti-inflammatory medication. Horses that are not eating well may also require parenteral nutrition. Horses usually require 3–6 days of treatment before clinical signs improve.Due to the risk of endotoxemia, laminitis is a potential complication for horses suffering from colitis, and may become the primary cause for euthanasia. Horses are also at increased risk of thrombophlebitis.
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Gastric ulceration Horses form ulcers in the stomach fairly commonly, a disease called equine gastric ulcer syndrome. Risk factors include confinement, infrequent feedings, a high proportion of concentrate feeds, such as grains, excessive non-steroidal anti-inflammatory drug use, and the stress of shipping and showing. Gastric ulceration has also been associated with the consumption of cantharidin beetles in alfalfa hay which are very caustic when chewed and ingested. Most ulcers are treatable with medications that inhibit the acid producing cells of the stomach. Antacids are less effective in horses than in humans, because horses produce stomach acid almost constantly, while humans produce acid mainly when eating. Dietary management is critical. Bleeding ulcers leading to stomach rupture are rare.
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Right dorsal colitis Long-term use of NSAIDs can lead to mucosal damage of the colon, secondary to decreased levels of homeostatic prostaglandins. Mucosal injury is usually limited to the right dorsal colon, but can be more generalized. Horses may display acute or chronic intermittent colic, peripheral edema secondary to protein losing enteropathy, decreased appetite, and diarrhea. Treatment involves decreasing the fiber levels of the horse's diet by reducing grass and hay, and placing the horse on an easily digestible pelleted feed until the colon can heal. Additionally, the horse may be given misoprostol, sucralfate, and psyllium to try to improve mucosal healing, as well as metronidazole to reduce inflammation of the colon.
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Tumors Strangulating pedunculated lipoma Benign fatty tumors known as lipomas can form on the mesentery. As the tumor enlarges, it stretches the connective tissue into a stalk which can wrap around a segment of bowel, typically small intestine, cutting off its blood supply. The tumor forms a button that latches onto the stalk of the tumor, locking it on place, and requiring surgery for resolution. Surgery involves cutting the stalk of the tumor, untwisting the bowel, and removing bowel that is no longer viable. If the colic is identified and taken to surgery quickly, there is a reasonable rate of success of 50–78%. This type of colic is most commonly associated with ponies, and aged geldings, 10 years and older, probably because of fat distribution in this group of animals.
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Other cancers Cancers (neoplasia) other than lipoma are relatively rare causes of colic. Cases have been reported with intestinal cancers including intestinal lymphosarcoma, leiomyoma, and adenocarcinoma, stomach cancers such as squamous cell carcinoma, and splenic lymphosarcoma.Gastric squamous cell carcinoma is most often found in the non-glandular region of the stomach of horses greater than 5 years of age, and horses often present with weight loss, anorexia, anemia, and ptyalism. Gastric carcinoma is usually diagnosed via gastroscopy, but may sometimes be felt on rectal if they have metastasized to the peritoneal cavity. Additionally, laparoscopy can also diagnose metastasized cancer, as can presence of neoplastic cells on abdominocentesis. Often the signs of intestinal neoplasia are non-specific, and include weight loss and colic, usually only if obstruction of the intestinal lumen occurs.
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Ileus Ileus is the lack of motility of the intestines, leading to a functional obstruction. It often occurs postoperatively following any type of abdominal surgery, and 10–50% of all cases of surgical colic will develop this complication, including 88% of horses with a strangulating obstructions and 41% of all colics with a large intestinal lesion. The exact cause is unknown, but is suspected to be due to inflammation of the intestine, possibly a result of manipulation by the surgeon, and increased sympathetic tone. It has a high fatality rate of 13–86%.Ileus diagnosed based on several criteria: Nasogastric reflux: 4 liters or greater in a single intubation, or greater than 2 liters of reflex over more than one intubation A heart rate greater than 40 bpm Signs of colic, which may vary from mild to severe Distended small intestine, based on rectal or abdominal ultrasound findings. On ultrasound, ileus presents as more than 3 loops of distended small intestine, with a lack of peristaltic waves.This form of colic is usually managed medically. Because there is no motility, intestinal contents back up into the stomach. Therefore, periodic decompression of the stomach though nasogastric intubation is essential to prevent rupture. Horses are monitored closely following abdominal surgery, and a sudden increase in heart rate indicates the need to check for nasogastric reflux, as it is an early indication of postoperative ileus. The horse is placed on intravenous fluids to maintain hydration and electrolyte balance and prevent hypovolemic shock, and rate of fluids is calculated based on daily maintenance requirement plus fluid lose via nasogastric reflux.
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Motility is encouraged by the use of prokinetic drugs such as erythromycin, metoclopramide, bethanechol and lidocaine, as well as through vigorous walking, which has also been shown to have a beneficial effect on GI motility. Lidocaine is especially useful, as it not only encourages motility, but also has anti-inflammatory properties and may ameliorate some post-operative pain. Metoclopramide has been shown to reduce reflux and hospital stay, but does has excitatory effects on the central nervous system. Anti-inflammatory drugs are used to decrease inflammation of the GI tract, which is thought to be the underlying cause of the disease, as well as to help control any absorption of LPS in cases of endotoxemia since the substance decreases motility. However, care must be taken when giving these drugs, as NSAIDs have been shown to alter intestinal motility.Large intestinal ileus is most commonly seen in horses following orthopedic surgery, but its risk is also increased in cases where post-operative pain is not well-controlled, after long surgeries, and possibly following ophthalmologic surgeries. It is characterized by decreased manure output (<3 piles per day), rather than nasogastric reflux, as well as decreased gut sounds, signs of colic, and the occasional impaction of the cecum or large colon. Cecal impactions can be fatal, so care must be taken to monitor the horse for large intestinal ileus after orthopedic surgery, primarily by watching for decreased manure production.
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Decreased intestinal motility can also be the result of drugs such as Amitraz, which is used to kill ticks and mites. Xylazine, detomidine, and butorphanol also reduce motility, but will not cause colic if appropriately administered.
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Parasites Ascarids (roundworms) Occasionally there can be an obstruction by large numbers of roundworms. This is most commonly seen in young horses as a result of a very heavy infestation of Parascaris equorum that can subsequently cause a blockage and rupture of the small intestine. Rarely, dead worms will be seen in reflux. Deworming heavily infected horses may cause a severe immune reaction to the dead worms, which can damage the intestinal wall and cause a fatal peritonitis. Veterinarians often treat horses with suspected heavy worm burdens with corticosteroids to reduce the inflammatory response to the dead worms. Blockages of the small intestine, particularly the ileum, can occur with Parascaris equorum and may well require colic surgery to remove them manually. Large roundworm infestations are often the result of a poor deworming program. Horses develop immunity to parascarids between 6 months age and one year and so this condition is rare in adult horses. Prognosis is fair unless the foal experiences hypovolemia and septic shock, with a survival rate of 33%.
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Tapeworms Tapeworms at the junction of the cecum have been implicated in causing colic. The most common species of tapeworm in the equine is Anoplocephala perfoliata. However, a 2008 study in Canada indicated that there is no connection between tapeworms and colic, contradicting studies performed in the UK.
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Cyathostomes Acute diarrhea can be caused by cyathostomes or "small Strongylus-type" worms that are encysted as larvae in the bowel wall, particularly if large numbers emerge simultaneously. The disease most frequently occurs in winter time. Pathological changes of the bowel reveal a typical "pepper and salt" color of the large intestines. Animals suffering from cyathostominosis usually have a poor deworming history. There is now a lot of resistance to fenbendazole in the UK.
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Large strongyles Large strongyle worms, most commonly Strongylus vulgaris, are implicated in colic secondary to non-strangulating infarction of the cranial mesenteric artery supplying the intestines, most likely due to vasospasm. Usually the distal small intestine and the large colon are affected, but any segment supplied by this artery can be compromised. This type of colic has become relatively rare with the advent of modern anthelminthics. Clinical signs vary based on the degree of vascular compromise and the length of intestine that is affected, and include acute and severe colic seen with other forms of strangulating obstruction, so diagnosis is usually made based on anthelminthic administration history although may be definitively diagnosed during surgical exploratoration. Treatment includes typical management of colic signs and endotoxemia, and the administration of aspirin to reduce the risk of thrombosis, but surgery is usually not helpful since lesions are often patchy and may be located in areas not easily resected.
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Foal colic Meconium impactions Meconium, or the first feces produced by the foal, is a hard pelleted substance. It is normally passed within the first 24 hours of the foal's life, but may become impacted in the distal colon or rectum. Meconium impaction is most commonly is seen in foals 1–5 days of age, and is more common in miniature foals and in colts more than fillies (possibly because fillies have a wider pelvis). Foals will stop suckling, strain to defecate (presents as an arched back and lifted tail), and may start showing overt signs of colic such as rolling and getting up and down. In later stages, the abdomen will distend as it continues to fill with gas and feces. Meconium impactions are often diagnosed by clinical signs, but digital examination to feel for impacted meconium, radiographs, and ultrasound may also be used.
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Treatment for meconium impaction typically involves the use of enemas, although persistent cases may require mineral oil or IV fluids. It is possible to tell that the meconium has passed when the foal begins to produce a softer, more yellow manure. Although meconium impactions rarely cause perforation, and are usually not life-threatening, foals are at risk of dehydration and may not get adequate levels of IgG due to decreased suckling and not enough ingestion of colostrum. Additionally, the foals will eventually bloat, and will require surgical intervention. Surgery in a foal can be especially risky due to immature immune system and low levels of ingested colostrum.
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Lethal white syndrome Lethal white syndrome, or ileocolonic aganglionosis, will result in meconium impaction since the foal does not have adequate nerve innervation to the large intestine, in essence, a nonfunctioning colon. Foals that are homozygous for the frame overo gene, often seen in Paint horse heritage, will develop the condition. They present with signs of colic within the first 12 hours after birth, and die within 48 hours due to constipation. This syndrome is not treatable.
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Congenital abnormalities Atresia coli and atresia ani can also present as meconium impaction. The foal is missing the lumen of its distal colon or anus, respectively, and usually show signs of colic within 12–24 hours. Atresia coli is usually diagnosed with barium contrast studies, in which foals are given barium, and then radiographed to see if and where the barium is trapped. Atresia ani is simply diagnosed with digital examination by a veterinarian. Both situations requires emergency surgery to prevent death, and often still has a poor prognosis for survival with surgical correction.
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Infectious organisms Clostridial enterocolitis due to infection by Clostridium perfringens is most commonly seen in foals under 3 months of age. Clostridial toxins damage the intestine, leading to dehydration and toxemia. Foals usually present with signs of colic, decreased nursing, abdominal distention, and diarrhea which may contain blood. Diagnosis is made with fecal culture, and while some foals do not require serious intervention, others need IV fluids, antibiotics, and aggressive treatment, and may still die. Other bacterial infections that may lead to enterocolitis include Salmonella, Klebsiella, Rhodococcus equi, and Bacteroides fragilis.Parasitic infection, especially with threadworms (Strongyloides westeri) and ascarids (Parascaris equorum) can produce signs of colic in foals (See Ascarids). Other conditions that may lead to signs of colic in foals include congenital abnormalities, gastric ulcers (see Gastric ulceration), which may lead to gastric perforation and peritonitis, small intestine volvulus, and uroabdomen secondary to urinary bladder rupture.
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Herniation Inguinal herniation Inguinal hernias are most commonly seen in Standardbred and Tennessee Walking Horse stallions due, likely due to a breed prevalence of a large inguinal ring, as well as Saddlebred and Warmblood breeds. Inguinal hernias in adult horses are usually strangulating (unlike foals, which are usually non-strangulating). Stallions usually display acute signs of colic, and a cool, enlarged testicle on one side. Hernias are classified as either indirect, in which the bowel remains in the parietal vaginal tunic, or direct, in which case it ruptures through the tunic and goes subcutaneously. Direct hernias are seen most commonly in foals, and usually congenital. Indirect hernias may be treated by repeated manual reduction, but direct hernias often require surgery to correct. The testicle on the side of resection will often require removal due to vascular compromise, although prognosis for survival is good (75%) and the horse may be used for breeding in the future.
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Umbilical herniation Although umbilical hernias are common in foals, strangulation is rare, occurring only 4% of the time and usually involving the small intestine. Rarely, the hernia will only involve part of the intestinal wall (termed a Richter's hernia), which can lead to an enterocutaneous fistula. Strangulating umbilical hernias will present as enlarged, firm, warm, and painful with colic signs. Foals usually survive to discharge.
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Diaphragmatic herniation Diaphragmatic hernias are rare in horses, accounting for 0.3% of colics. Usually the small intestine herniates through a rent in the diaphragm, although any part of the bowel may be involved. Hernias are most commonly acquired, not congenital, with 48% of horses having a history of recent trauma, usually through during parturition, distention of the abdomen, a fall, or strenuous exercise, or direct trauma to the chest. Congenital hernias occur most commonly in the most ventral part of the diaphragm, while acquired hernias are usually seen at the junction of the muscular and tendinous sections of the diaphragm. Clinical signs usually are similar to an obstruction, but occasionally decreased lung sounds may be heard in one section of the chest, although dyspnea is only seen in approximately 18% of horses. Ultrasound and radiography may both be used to diagnose diaphragmatic herniation.
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Toxins Ingested toxins are rarely a cause of colic in the horse. Toxins that can produce colic signs include organophosphates, monensin, and cantharidin. Additionally, overuse of certain drugs such as NSAIDs may lead to colic signs (See Gastric ulceration and Right dorsal colitis).
Uterine tears and torsions Uterine tears often occur a few days post parturition. They can lead to peritonitis and require surgical intervention to fix. Uterine torsions can occur in the third trimester, and while some cases may be corrected if the horse in anesthetized and rolled, others require surgical correction.
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Other causes that may show clinical signs of colic Strictly speaking, colic refers only to signs originating from the gastrointestinal tract of the horse. Signs of colic may be caused by problems other than the GI-tract e.g. problems in the liver, ovaries, spleen, urogenital system, testicular torsion, pleuritis, and pleuropneumonia. Diseases which sometimes cause symptoms which appear similar to colic include uterine contractions, laminitis, and exertional rhabdomyolysis. Colic pain secondary to kidney disease is rare.
Diagnosis:
Many different diagnostic tests are used to diagnose the cause of a particular form of equine colic, which may have greater or lesser value in certain situations. The most important distinction to make is whether the condition is managed medically or surgically. If surgery is indicated, then it must be performed as soon as possible, as delay is a dire prognostic indicator.
Diagnosis:
History A thorough history is always taken, including signalment (age, sex, breed), recent activity, diet and recent dietary changes, anthelmintic history, if the horse is a cribber, fecal quality and when it was last passed, and any history of colic. The most important factor is time elapsed since onset of clinical signs, as this has a profound impact on prognosis. Additionally, a veterinarian will need to know any drugs given to the horse, their amount, and the time they were given, as those can help with the assessment of the colic progression and how it is responding to analgesia.
Diagnosis:
Physical examination Heart rate rises with progression of colic, in part due to pain, but mainly due to decreased circulating volume secondary to dehydration, decreased preload from hypotension, and endotoxemia. The rate is measured over time, and its response to analgesic therapy ascertained. A pulse that continues to rise in the face of adequate analgesia is considered a surgical indication. Mucous membrane color can be assessed to appreciate the severity of haemodynamic compromise. Pale mucous membranes may be caused by decreased perfusion (as with shock), anemia due to chronic blood loss (seen with GI ulceration), and dehydration. Pink or cyanotic (blue) membrane colors are associated with a greater chance of survival (55%). Dark red, or "injected", membranes reflect increased perfusion, and the presence of a "toxic line" (a red ring over the top of the teeth where it meets the gum line, with pale or gray mucous membranes) can indicate endotoxemia. Both injected mucous membranes and the presence of a toxic line correlate to a decreased likelihood of survival, at 44%. Capillary refill time is assessed to determine hydration levels and highly correlates to perfusion of the bowel. A CRT of < 2 seconds has a survival rate of 90%, of 2.5–4 seconds a survival rate of 53%, and > 4 seconds a survival rate of 12%.Laboratory tests can be performed to assess the cardiovascular status of the patient. Packed cell volume (PCV) is a measure of hydration status, with a value 45% being considered significant. Increasing values over repeated examination are also considered significant. The total protein (TP) of blood may also be measured, as an aid in estimating the amount of protein loss into the intestine. Its value must be interpreted along with the PCV, to take into account the hydration status. When laboratory tests are not available, hydration can be crudely assessed by tenting the skin of the neck or eyelid, looking for sunken eyes, depression, high heart rate, and feeling for tackiness of the gums. Jugular filling and quality of the peripheral pulses can be used to approximate blood pressure. Capillary refill time (CRT) may be decreased early in the colic, but generally prolongs as the disease progresses and cardiovascular status worsens.
Diagnosis:
Weight and body condition score (BCS) is important when evaluating a horse with chronic colic, and a poor BCS in the face of good quality nutrition can indicate malabsorptive and maldigestive disorders.Rectal temperature can help ascertain if an infectious or inflammatory cause is to blame for the colic, which is suspected if the temperature if >103F. Temperature should be taken prior to rectal examination, as the introduction of air will falsely lower rectal temperature. Coolness of extremities can indicate decreased perfusion secondary to endotoxemia. Elevated respiratory rate can indicate pain as well as acid-base disturbances. A rectal examination, auscultation of the abdomen, and nasogastric intubation should always occur in addition to the basic physical exam.
Diagnosis:
Rectal examination Rectal examinations are a cornerstone of colic diagnosis, as many large intestinal conditions can be definitively diagnosed by this method alone. Due to the risk of harm to the horse, a rectal examination is performed by a veterinarian. Approximately 40% of the gastrointestinal tract can be examined by rectal palpation, although this can vary based on the size of the horse and the length of the examiner's arm. Structures that can be identified include the aorta, caudal pole of the left kidney, nephrosplenic ligament, caudal border of the spleen, ascending colon (left dorsal and ventral, pelvic flexure), the small intestine if distended (it is not normally palpable on rectal), the mesenteric root, the base of the cecum and the medial cecal band, and rarely the inguinal rings. The location within the colon is identified based on size, presence of sacculations, number of bands, and if fecal balls are present.Displacements, torsions, strangulations, and impactions may be identified on rectal examination. Other non-specific findings, such as dilated small intestinal loops, may also be detected, and can play a major part in determining if surgery is necessary. Thickness of the intestinal walls may indicate infiltrative disease or abnormal muscular enlargement. Roughening of the serosal surface of the intestine can occur secondary to peritonitis. Horses that have had gastrointestinal rupture may have gritty feeling and free gas in the abdominal cavity. Surgery is usually suggested if rectal examination finds severe distention of any part of the GI tract, a tight cecum or multiple tight loops of small intestine, or inguinal hernia. However, even if the exact cause can not be determined on rectal, significant abnormal findings without specific diagnosis can indicate the need for surgery. Rectal examinations are often repeated over the course of a colic to monitor the GI tract for signs of change.
Diagnosis:
Rectals are a risk to the practitioner, and the horse is ideally examined either in stocks or over a stall door to prevent kicking, with the horse twitched, and possibly sedated if extremely painful and likely to try to go down. Buscopan is sometimes used to facilitate rectal examination and reduce the risk of tears, because it decreases the smooth muscle tone of the gastrointestinal tract, but can be contraindicated and will produce a very rapid heart rate. Because the rectum is relatively fragile, the risk of rectal tears is always present whenever an examination is performed. Severe rectal tears often result in death or euthanasia. However, the diagnostic benefits of a rectal examination almost always outweigh these risks.
Diagnosis:
Nasogastric intubation Passing a nasogastric tube (NGT) is useful both diagnostically and therapeutically. A long tube is passed through one of the nostrils, down the esophagus, and into the stomach. Water is then pumped into the stomach, creating a siphon, and excess fluid and material (reflux) is pulled off the stomach. Healthy horses will often have less than 1 liter removed from the stomach; any more than 2 litres of fluid is considered to be significant. Horses are unable to vomit or regurgitate, therefore nasogastric intubation is therapeutically important for gastric decompression. A backup of fluid in the gastrointestinal tract will cause it to build up in the stomach, a process that can eventually lead to stomach rupture, which is inevitably fatal.Backing up of fluid through the intestinal tract is usually due to a downstream obstruction, ileus, or proximal enteritis, and its presence usually indicates a small intestinal disease. Generally, the closer the obstruction is to the stomach, the greater amount of gastric reflux will be present. Approximately 50% of horses with gastric reflux require surgery.
Diagnosis:
Auscultation Auscultation of the abdomen is subjective and non-specific, but can be useful. Auscultation typically is performed in a four-quadrant approach: Upper flank, right side: corresponds to the cecum Caudoventral abdomen, right side: corresponds to the colon Upper flank, left side: corresponds to the small intestine Caudoventral abdomen, left side: corresponds to colonEach quadrant should ideally be listened to for 2 minutes. Gut sounds (borborygmi) correlate to motility of the bowel, and care should be taken to note intensity, frequency, and location. Increased gut sounds (hyper-motility) may be indicative of spasmodic colic. Decreased sound, or no sound, may be suggestive of serious changes such as ileus or ischemia, and persistence of hypomotile bowel often suggests the need for surgical intervention. Gut sounds that occur concurrently with pain may indicate obstruction of the intestinal lumen. Sounds of gas can occur with ileus, and those of fluid are associated with diarrhea which may occur with colitis. Sand may sometimes be heard on the ventral midline, presenting a typical "waves on the beach" sound in a horse with sand colic after the lower abdomen is forcefully pushed with a fist. Abdominal percussion ("pinging") can sometimes be used to determine if there is gas distention in the bowel. This may be useful to help determine the need for trocarization, either of the cecum or the colon.
Diagnosis:
Abdominal ultrasound Ultrasound provides visualization of the thoracic and abdominal structures, and can sometimes rule out or narrow down a diagnosis. Information that may be gleaned from ultrasonographic findings include the presence of sand, distention, entrapment, strangulation, intussusception, and wall thickening of intestinal loops, as well as diagnose nephrosplenic entrapment, peritonitis, abdominal tumors, and inguinal or scrotal hernias. Abdominal ultrasound requires an experienced operator to accurately diagnose the cause of colic. It may be applied against the side of the horse, as well as transrectally.Sand presents as a homogeneous gray and allows the ultrasound waves to penetrate deep. It is distinguishable from feces, which is less homogeneous, and gas colic, which does not allow the operator to see pass the gas. Additionally, the sand usually "sparkles" on ultrasound if it moves. Sand is best diagnosed using a 3.5 megahertz probe. Horses with gastrointestinal rupture will have peritoneal fluid accumulation, sometimes with debris, visible on ultrasound. Horses with peritonitis will often have anechoic fluid, or material in between visceral surfaces.
Diagnosis:
Differentiation between proximal enteritis and small intestinal obstruction is important to ensure correct treatment, and can be assisted with the help of ultrasound. Horses with small intestinal obstruction will usually have an intestinal diameter of -10 cm with a wall thickness of 3-5mm. Horses with proximal enteritis usually have an intestinal diameter that is narrower, but wall thickness is often greater than 6mm, containing a hyperechoic or anechoic fluid, with normal, increased, or decreased peristalsis. However, obstructions that have been present for some time may present with thickened walls and distention of the intestine.Horses experiencing intussusception may have a characteristic "bullseye" appearance of intestine on ultrasound, which is thickened, and distended intestine proximal to the affected area. Those experiencing nephrosplenic entrapment will often have ultrasonographic changes including an inability to see the left kidney and/or tail of the spleen.
Diagnosis:
Abdominocentesis (belly tap) Abdominocentesis, or the extraction of fluid from the peritoneum, can be useful in assessing the state of the intestines. Normal peritoneal fluid is clear, straw-colored, and of serous consistency, with a total nucleated cell count of less than 5000 cells/microliter (24–60% which are neutrophils) and a total protein of 2.5 g/dL.Abdominocentesis allows for the evaluation of red and white blood cells, hemoglobin concentration, protein levels, and lactate levels. A high lactate in abdominal fluid suggests intestinal death and necrosis, usually due to strangulating lesion, and often indicates the need for surgical intervention. A strangulating lesion may produce high levels of red blood cells, and a serosanguinous fluid containing blood and serum. White blood cell levels may increase if there is death of intestine that leads to leakage of intestinal contents, which includes high levels of bacteria, and a neutrophil to monocyte ratio greater than or equal to 90% is suggestive of a need for surgery. "High" nucleated cell counts (15,000–800,000 cells/microliter depending on the disease present) occur with horses with peritonitis or abdominal abscesses. The protein level of abdominal fluid can give information as to the integrity of intestinal blood vessels. High protein (> 2.5 mg/dL) suggests increased capillary permeability associated with peritonitis, intestinal compromise, or blood contamination. Horses with gastrointestinal rupture will have elevated protein the majority of the time (86.4%) and 95.7% will have bacteria present. Occasionally, with sand colic, it is possible to feel the sand with the tip of the needle.Clinical analysis is not necessarily required to analyze the fluid. Simple observation of color and turbidity can be useful in the field. Sanguinous fluid indicates an excess of red blood cells or hemoglobin, and may be due to leakage of the cells through a damaged intestinal wall, splenic puncture during abdominocentesis, laceration of abdominal viscera, or contamination from a skin capillary.
Diagnosis:
Cloudy fluid is suggestive of an increased number of cells or protein.
White fluid indicates chylous effusion.
Green fluid indicates either gastrointestinal rupture or enterocentesis, and a second sample should be drawn to rule out the latter. Gastrointestinal rupture produces a color change in peritoneal fluid in 85.5% of cases.
Colorless (dilute) peritoneal fluid, especially in large quantities, can indicate ascites or uroperitoneum (urine in the abdomen).
Large amount of fluid can indicate acute peritonitis.
Diagnosis:
Abdominal distension Any degree of abdominal distension is usually indicative of a condition affecting the large intestines, as distension of structures upstream of here would not be large enough to be visible externally. Abdominal distention may indicate the need for surgical intervention, especially if present with severe signs of colic, high heart rate, congested mucous membranes, or absent gut sounds.
Diagnosis:
Fecal examination The amount of feces produced, and its character can be helpful, although as changes often occur relatively distant to the anus, changes may not be seen for some time. In areas where sand colic is known to be common, or if the history suggests it may be a possibility, faeces can be examined for the presence of sand, often by mixing it in water and allowing the sand to settle out over 20 minutes. However, sand is sometimes present in a normal horse's feces, so the quantity of sand present must be assessed. Testing the feces for parasite load may also help diagnose colic secondary to parasitic infection.
Diagnosis:
Radiography, gastroscopy, and laparoscopy Radiography Radiographs (x-rays) are sometimes used to look for sand and enteroliths. Due to the size of the adult horse's abdomen, it requires a powerful machine that is not available to all practitioners. Additionally, the quality of these images is sometimes poor.
Gastroscopy Gastroscopy, or endoscopic evaluation of the stomach, is useful in chronic cases of colic suspected to be caused by gastric ulcers, gastric impactions, and gastric masses. A 3-meter scope is required to visualize the stomach of most horses, and the horse must be fasted prior to scoping.
Laparoscopy Laparoscopy involves inserting a telescoping camera approximately 1 cm in diameter into the horse's abdomen, through a small incision, to visualize the gastrointestinal tract. It may be performed standing or under general anesthesia, and is less invasive than an exploratory celiotomy (abdominal exploratory surgery).
Rectal biopsy Rectal biopsy is rarely performed due to its risks of abscess formation, rectal perforation and peritonitis, and because it requires a skilled clinical to perform. However, it can be useful in cases of suspected intestinal cancer, as well as some inflammatory diseases (such as IBD) and infiltrative diseases, like granulomatous enteritis.
Clinical signs:
Clinical signs of colic are usually referable to pain, although the horse may appear depressed rather than painful in cases of necrosis (tissue death) of the gastrointestinal tract, inflammation of the intestines, endotoxemia, or significant dehydration. Pain levels are often used to determine the need for surgery (See Surgical intervention). Horses are more likely to require surgery if they display severe clinical signs that can not be controlled by the administration of analgesics and sedatives, or have persistent signs that require multiple administrations of such drugs. Heart rate is often used as a measure of the animal's pain level and a heart rate >60 bpm is more likely to require surgery. However, this measure can be deceiving in the early stages of a severe colic, when the horse may still retain a relatively low rate. Additionally, pain tolerance of the individual must be taken into account, since very stoic animals with severe cases of colic may not show adequate levels of pain to suggest the need for surgery. High heart rates (>60 bpm), prolonged capillary refill time (CRT), and congested mucous membranes suggest cardiovascular compromise and the need for more intense management. Decreased or absent gut sounds often suggest the need for surgical intervention if prolonged.A horse showing severe clinical signs, followed by a rapid and significant improvement, may have experienced gastrointestinal perforation. While this releases the pressure that originally caused so much discomfort for the horse, it results in a non-treatable peritonitis that requires euthanasia. Soon after this apparent improvement, the horse will display signs of shock, including an elevated heart rate, increased capillary refill time, rapid shallow breathing, and a change in mucous membrane color. It may also be pyretic, act depressed, or become extremely painful.Gas distention usually produces mild clinical signs, but in some cases leads to severe signs due to pressure and tension on the mesentery. Simple obstructions often present with a slightly elevated heart rate (<60 bpm) but normal CRT and mucous membrane color. Strangulating obstructions are usually extremely painful, and the horse may have abdominal distention, congested mucous membranes, altered capillary refill time, and other signs of endotoxemia.
Clinical signs:
General Elevated body temperature: most commonly associated with medically managed colics such as enteritis, colitis, peritonitis, and intestinal rupture Elevated heart rate Elevated respiratory rate Increased capillary refill time Change in mucous membrane (gum) color (See Physical examination) Change in the degree of gut sounds (See Auscultation) Pawing Increased attention toward the abdomen, including flank watching (turning of the head to look at the abdomen and/or hind quarters), nipping, biting, or kicking Repeatedly lying down and rising, which may become violent when the colic is severe Rolling, especially when not followed by shaking after standing, and which may become violent when the colic is severe (thrashing) Sweating Change in activity level: lethargy, pacing, or a constant shifting of weight when standing Change in feces: decreased fecal output or a change in consistency Repeated flehmen response Stretching, abnormal posturing, or frequent attempts to urinate Groaning Bruxism Excess salivation (ptyalism) Excessive yawning Loss of appetite Abdominal distention Dorsal recumbency in foals Poor coat or weight loss (chronic colic)
Medical management:
Colic may be managed medically or surgically. Severe clinical signs often suggest the need for surgery, especially if they can not be controlled with analgesics. Immediate surgical intervention may be required, but surgery can be counter-indicated in some cases of colic, so diagnostic tests are used to help discover the cause of the colic and guide the practitioner in determining the need for surgery (See Diagnosis). The majority of colics (approximately 90%) can be successfully managed medically.
Medical management:
Analgesia and sedation The intensity of medical management is dependent on the severity of the colic, its cause, and the financial capabilities of the owner. At the most basic level, analgesia and sedation is administered to the horse. The most commonly used analgesics for colic pain in horses are NSAIDs, such as flunixin meglumine, although opioids such as butorphanol may be used if the pain is more severe. Butrophanol is often given with alpha-2 agonists such as xylazine and detomidine to prolong the analgesic effects of the opioid. Early colic signs may be masked with the use of NSAIDs, so some practitioners prefer to examine the horse before they are given by the owner.
Medical management:
Nasogastric intubation and gastric decompression Nasogastric intubation, a mainstay of colic management, is often repeated multiple times until resolution of clinical signs, both as a method of gastric reflux removal and as a way to directly administer fluids and medication into the stomach. Reflux must be removed periodically to prevent distention and possible rupture of the stomach, and to track reflux production, which aids in monitoring the progression of the colic. Its use is especially important in the case of strangulating obstruction or enteritis, since both of these cause excessive secretion of fluid into the intestine, leading to fluid back-up and distention of the stomach. Nasogastric intubation also has the benefit of providing pain relief resulting from gastric distention.
Medical management:
Fluid support Fluids are commonly given, either orally by nasogastric tube or by intravenous catheter, to restore proper hydration and electrolyte balance. In cases of strangulating obstruction or enteritis, the intestine will have decreased absorption and increased secretion of fluid into the intestinal lumen, making oral fluids ineffective and possibly dangerous if they cause gastric distention and rupture. This process of secretion into the intestinal lumen leads to dehydration, and these horse require large amounts of IV fluids to prevent hypotension and subsequent cardiovascular collapse. Fluid rates are calculated by adding the fluid lost during each collection of gastric reflux to the daily maintenance requirement of the horse. Due to the fact that horses absorb water in the cecum and colon, the IV fluid requirement of horses with simple obstruction is dependent on the location of the obstruction. Those that are obstructed further distally, such as at the pelvic flexure, are able to absorb more oral fluid than those obstructed in the small intestine, and therefore require less IV fluid support. Impactions are usually managed with fluids for 3–5 days before surgery is considered. Fluids are given based on results of the physical examination, such as mucous membrane quality, PCV, and electrolyte levels. Horses in circulatory shock, such as those suffering from endotoxemia, require very high rates of IV fluid administration. Oral fluids via nasogastric tube are often given in the case of impactions to help lubricate the obstruction. Oral fluids should not be given if significant amounts of nasogastric reflux are obtained. Access to food and water will often be denied to allow careful monitoring and administration of what is taken in by the horse.
Medical management:
Intestinal lubricants and laxatives In addition to fluid support, impactions are often treated with intestinal lubricants and laxatives to help move the obstruction along. Mineral oil is the most commonly used lubricant for large colon impactions, and is administered via nasogastric tube, up to 4 liters once or twice daily. It helps coat the intestine, but is not very effective for severe impactions or sand colic since it may simply bypass the obstruction. Mineral oil has the added benefit of crudely measuring GI transit time, a process which normally takes around 18 hours, since it is obvious when it is passed. The detergent dioctyl sodium sulfosuccinate (DDS) is also commonly given in oral fluids. It is more effective in softening an impaction than mineral oil, and helps stimulate intestinal motility, but can inhibit fluid absorption from the intestine and is potentially toxic so is only given in small amounts, two separate times 48 hours apart. Epsom salts are also useful for impactions, since they act both as an osmotic agent, to increase fluid in the GI tract, and as a laxative, but do run the risk of dehydration and diarrhea. Strong laxatives are not recommended for treating impactions.
Medical management:
Nutritional support Horses are withheld feed when colic signs are referable to gastrointestinal disease. In long-standing cases, parenteral nutrition may be instituted. Once clinical signs improve, the horse will slowly be re-fed (introduced back to its normal diet), while being carefully monitored for pain.
Medical management:
Endotoxemia prevention Endotoxemia is a serious complication of colic and warrants aggressive treatment. Endotoxin (lipopolysaccharide) is released from the cell wall of gram-negative bacteria when they die. Normally, endotoxin is prevented from entering systemic circulation by the barrier function of the intestinal mucosa, antibodies and enzymes which bind and neutralize it and, for the small amount that manages to enter the blood stream, removal by Kupffer cells in the liver. Endotoxemia occurs when there is an overgrowth and secondary die-off of gram negative bacteria, releasing mass quantities of endotoxin. This is especially common when the mucosal barrier is damaged, as with ischemia of the GI tract secondary to a strangulating lesion or displacement. Endotoxemia produces systemic effects such as cardiovascular shock, insulin resistance, and coagulation abnormalities.Fluid support is essential to maintain blood pressure, often with the help of colloids or hypertonic saline. NSAIDs are commonly given to reduce systemic inflammation. However, they decrease the levels of certain prostaglandins that normally promote healing of the intestinal mucosa, which subsequently increases the amount of endotoxin absorbed. To counteract this, NSAIDs are sometimes administered with a lidocaine drip, which appears to reduce this particular negative effect. Flunixin may be used for this purpose at a dose lower than that used for analgesia, so can be safely given to a colicky horse without risking masking signs that the horse requires surgery. Other drugs that bind endotoxin, such as polymyxin B and Bio-Sponge, are also often used. Polymixin B prevents endotoxin from binding to inflammatory cells, but is potentially nephrotoxic, so should be used with caution in horses with azotemia, especially neonatal foals. Plasma may also be given with the intent of neutralizing endotoxin.Laminitis is a major concern in horses suffering from endotoxemia. Ideally, prophylactic treatment should be provided to endotoxic horses, which includes the use of NSAIDs, DMSO, icing of the feet, and frog support. Horses are also sometimes administered heparin, which is thought to reduce the risk of laminitis by decreasing blood coagulability and thus blood clot formation in the capillaries of the foot.
Medical management:
Case-specific drug treatment Specific causes of colic are best managed with certain drugs. These include: Spasmolytic agents, most commonly Buscopan, especially in the case of gas colic.
Pro-motility agents: metoclopramide, lidocaine, bethanechol, and erythromycin are used in cases of ileus.
Anti-inflammatories are often used in the case of enteritis or colitis.
Anti-microbials may be administered if an infectious agent is suspected to be the underlying cause of colic.
Phenylephrine: used in cases of nephrosplenic entrapment to contract the spleen, and is followed by light exercise to try to shift the displaced colon back into its normal position.
Psyllium may be given via nasogastric tube to treat sand colic.
Anthelminthics for parasitic causes of colic.
Surgical intervention:
Surgery poses significant expense and risks, including peritonitis, the formation of adhesions, complications secondary to general anesthesia, injury upon recovery of the horse which may require euthanasia, dehiscence, or infection of the incisional site. Additionally, surgical cases may develop post-operative ileus which requires further medical management. However, surgery may be required to save the life of the horse, and 1–2% of all colics require surgical intervention. If a section of intestine is significantly damaged, it may need to be removed (resection) and the healthy parts reattached together (anastomosis). Horses may have up to 80% of their intestines removed and still function normally, without needing a special diet.
Surgical intervention:
Survival rates In the case of colics requiring surgery, survival rates are best improved by quick recognition of colic and immediate surgical referral, rather than waiting to see if the horse improves, which only increases the extent of intestinal compromise. Survival rates are higher in surgical cases that do not require resection and anastomosis. 90% of large intestinal colic surgeries that are not due to volvulus, and 20–80% of large colon volvuluses, are discharged; while 85–90% of non strangulating small intestinal lesions, and 65–75% of strangulating intestinal lesions are discharged. 10–20% of small intestinal surgical cases require a second surgery, while only 5% of large intestinal cases do so. Horses that survive colic surgery have a high rate of return to athletic function. According to one study, approximately 86% of horses discharged returned to work, and 83.5% returned to same or better performance.
Surgical intervention:
Adhesion formation Adhesions, or scar tissue between various organs that are not normally attached within the abdomen, may occur whenever an abdominal surgery is performed. It is often seen secondary to reperfusion injury where there is ischemic bowel or after intestinal distention. This injury causes neutrophils to move into the serosa and mesothelium to be lost, which the body then attempts to repair using fibrin and collagen, leading to adhesion formation between adjacent tissues with either fibrinous or fibrous material. Adhesions may encourage a volvulus, as the attachment provides a pivot point, or force a tight turn between two adjacent loops that are now attached, leading to partial obstruction. For this reason, clinical signs vary from silent lesions to acute obstruction, encouraging future colics including intestinal obstruction or strangulation, and requiring further surgery and risk of adhesion. Generally, adhesions form within the first two months following surgery. Adhesions occur most commonly in horses with small intestinal disease (22% of all surgical colics), foals (17%), those requiring enterotomy or a resection and anastomosis, or those that develop septic peritonitis.Prevention of adhesions begins with good surgical technique to minimize trauma to the tissue and thus reparative responses by the body. Several drugs and substances are used to try to prevent adhesion formation. Preoperative use of DMSO, a free radical scavenger, potassium penicillin, and flunixin meglumine may be given. The thick intestinal lubricant carboxymethylcellulose is often applied to the GI tract intraoperatively, to decrease trauma from handling by the surgeon and provide a physical barrier between the intestine and adjacent intestinal loops or abdominal organs. It has been shown to double the survival rate of horses, and its use is now a standard practice. Hyaluraonan can also be used to produce a physical barrier. Intraperitoneal unfractionated heparin is sometimes used, since it decreases fibrin formation and thus may decrease fibrinous adhesions. Omentectomy (removal of the omentum) is a quick, simple procedure that also greatly decreases the risk of adhesions, since the omentum is one organ that commonly adheres to the intestines. The abdomen is usually lavaged copiously before the abdomen is sutured closed, and anti-inflammatories are given postoperatively. A laparoscope may be used post-surgery to look for and break down adhesions, however there is risk of additional adhesions forming post-procedure. Encouraging motility post-surgery can also be useful, as it decreases the contact time between tissues. Adhesion-induced colic has a poor prognosis, with a 16% survival rate in one study.
Surgical intervention:
Post-operative care Small amounts of food is usually introduced as soon as possible after surgery, usually within 18–36 hours, to encourage motility and reduce the risk of ileus and the formation of adhesions. Often horses are stall rested with short bouts of hand walking to encourage intestinal motility. The incision site is carefully monitored for dehiscence, or complete failure of the incision leading to spillage of the abdominal contents out of the incision site, and the horse is not allowed turn-out until the incision has healed, usually after 30 days of stall rest. Abdominal bandages are sometimes used to help prevent the risk of dehiscence. Incisional infection doubles the time required for postoperative care, and dehiscence may lead to intestinal herniation, which reduces the likelihood of return to athletic function. Therefore, antibiotics are given 2–3 days after surgery, and temperature is constantly monitored, to help assess if an infection is present. Antibiotics are not used long-term due to the risk of antimicrobial resistance. The incision usually takes 6 months to reach 80% strength, while intestinal healing following resection and anastomosis is much faster, at a rate to 100% strength in 3 weeks. After the incision has healed adequately, the horse is turned out in a small area for another 2–3 months, and light exercise is added to improve the tone and strength of the abdominal musculature.
Surgical intervention:
Weight loss of 75–100 pounds is common after colic surgery, secondary to the decreased function of the gastrointestinal tract and from muscle atrophy that occurs while the horse is rested. This weight is often rapidly replaced.
Surgical intervention:
Draft horses tend to have more difficulty post-surgery because they are often under anesthesia for a longer period of time, since they have a greater amount of gastrointestinal tract to evaluate, and their increased size places more pressure on their musculature, which can lead to muscle damage. Miniature horses and fat ponies are at increased risk for hepatic lipidosis post-surgery, a serious complication.
Prevention:
The incidence of colic can be reduced by restricted access to simple carbohydrates including sugars from feeds with excessive molasses, providing clean feed and drinking water, preventing the ingestion of dirt or sand by using an elevated feeding surface, a regular feeding schedule, regular deworming, regular dental care, a regular diet that does not change substantially in content or proportion and prevention of heatstroke. Horses that bolt their feed are at risk of colic, and several management techniques may be used to slow down the rate of feed consumption.
Prevention:
Supplementing with previously mentioned form of pysllium fiber may reduce risk of sand colic if in a high-risk area. Most supplement forms are given one week per month and available wherever equine feed is purchased.
Prevention:
Turnout is thought to reduce the likelihood of colic, although this has not been proven. It is recommended that a horse receive ideally 18 hours of grazing time each day, as in the wild. However, many times this is difficult to manage with competition horses and those that are boarded, as well as for animals that are easy keepers with access to lush pasture and hence at risk of laminitis. Turnout on a dry lot with lower-quality fodder may have similar beneficial effects. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**CAMECA**
CAMECA:
CAMECA is a manufacturer of scientific instruments, namely material analysis instruments based on Charged particle beam, ions, or electrons.
History:
The company was founded as a subsidiary of Compagnie générale de la télégraphie sans fil (CSF), in 1929, as « Radio-cinéma » at the time of the emergence of the talkies. The job was to design and manufacture Movie projectors for big cinema screening rooms.After World War II, spurred on by Maurice Ponte, director of CSF and a future member of the French Academy of Sciences, the company manufactured scientific instruments developed in French University laboratories: the Spark Spectrometer at the beginning of the 1950s, the Castaing Microprobe from 1958, and Secondary Ion Analysers from 1968. Also in the early 1950s the company settled the factory in Courbevoie, boulevard Saint-Denis where it remained for more than fifty years. The Spark Spectrometer was abandoned at the end of the 1950s.The name of CAMECA, standing for Compagnie des Applications Mécaniques et Electroniques au Cinéma et à l'Atomistique, was given in 1954. The business of movie projectors stopped soon after 1960, but in the 1960s there was a short-lived revival of the film business through the adventure of the Scopitone.Since 1977, the year that the IMS3F was launched, CAMECA has had a virtual monopoly in the field of magnetic SIMS, but it shares the market for Castaing microprobe with Japanese competitors, including Jeol. The Semiconductor industry is a very important outlet for magnetic SIMS. At the end of the 20th century, CAMECA gained a foothold in a third analytical technique, Tomographic atom probe.In 1987, CAMECA left the Thomson-CSF group and was subject to a Leveraged buyout by its management and employees. In 2001, the company was sold to a small French Private equity fund, and then to another private equity fund controlled by the Carlyle Group, which sold CAMECA to Ametek, which merged CAMECA with Imago Scientific Instruments in 2010.From 1975, the number of employees has been about 200. Subsidiaries were created in the United States, Japan, Korea, Taïwan and Germany. These subsidiaries engaged in commercial and maintenance activities and employ a few dozen people.
The company in 2011:
According to the website of the company, in 2011 its business was in two different markets: scientific instruments dedicated to research activities; and metrology for the semiconductor industry. The latter market addresses semiconductor fabrication cleanrooms with a dedicated version of the Castaing electron probe based on the LEXES technique (low energy electron induced X-ray emission spectrometry) developed at the beginning of the 21st century.
The company in 2011:
CAMECA instruments are well known in academic communities, including the fields of geochemistry and planetary science, and CAMECA has been cited dozens of times in scientific journals such as Nature and Science.
In 2010, Ametek purchased the Wisconsin start-up Imago Scientific Instruments and attached it to CAMECA. CAMECA therefore holds the monopoly in the manufacturing of atom probe instruments with the LEAP brand name. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Nanopin film**
Nanopin film:
Nanopin film is an experimental material in nanotechnology developed in 2005 with unusual superhydrophobic properties [1]. A droplet of water makes contact with the surface of this film and forms an almost perfect sphere with a contact angle of 178°. This happens because it is covered with nanoscale, topped-off pins or cones perpendicular to the surface. The surface is regarded as a composite material with mostly air and a small fraction constituted by the tops of the cones. When the contact angle of the cone material is sufficiently large, Cassie's law predicts large contact angle values for the composite.
Nanopin film:
This particular nanopin film is produced with borosilicate glass. A solution of CoCl2•6H2O or cobalt chloride hexahydrate is heated at 60 °C for 24 hours in a chemical bath deposition to form a brucite type cobalt(II) hydroxide layer with composition CoOH1.13Cl0.09(CO3)0.39.0.05H20The top coating is provided by lauric acid in a separate step. A 3 square micrometer surface now contains on average 166 such cones with cone height of around 100 nm, and the cone diameter at the tip is 6.5 nm. The Cassie's law prediction for this material with the lauric acid surface area of 0.000612 and flat film contact angle of 75° is 177.8°. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Glazing jack**
Glazing jack:
A glazing jack or glazing machine is a type of machine used for polishing leather. The machine consists of a solid glass cylinder, typically around two inches (5 cm) in diameter and six inches (15 cm) in length, mounted to the end of a rotating or reciprocating arm. The arm repeatedly and rapidly draws the glass across the surface of the leather, with significant downward pressure, as the operator moves the leather underneath the arm.The repeated stroking of the leather smooths and compresses the surface and raises various color tones. Heat generated by friction during the glazing process can darken and harden the aniline finish of the leather, and can raise oils in the leather to the surface. Because no pigment is used, the porous structure of the leather remains visible, providing a depth to its appearance. The operator of the glazing jack can control the surface finish by varying the pressure of the tool and the number of strokes applied. Similarly to glazing, a copper or glass tool can be drawn across the leather by hand to create "sleeked" and "glassed" finishes, respectively.
Glazing jack:
Because jacking leather is a time-consuming and labor-intensive process, it is often reserved for more expensive or exotic leathers, such as reptile leathers. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Ulmus parvifolia 'Golden Rey'**
Ulmus parvifolia 'Golden Rey':
The Chinese Elm cultivar Ulmus parvifolia 'Golden Rey' is an American clone patented by B. Rey in 1990.
Description:
Chiefly distinguished by its spreading dome shape, the leaves emerge a uniform light yellow, maturing to chartreuse. The exfoliating bark is a mottled mix of grey, orange and brown.
Pests and diseases:
The species and its cultivars are highly resistant, but not immune, to Dutch elm disease, and unaffected by the Elm Leaf Beetle Xanthogaleruca luteola.
Cultivation:
'Golden Rey' is not known to be in cultivation beyond the United States.
Nurseries:
North America ForestFarm Nursery, Williams, Oregon, US.[1] Green Creek Nursery, Stephenville, Texas, US.
Rosebrook Nursery, Oklahoma City, Oklahoma, US. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Dental Procedure Education System**
Dental Procedure Education System:
The Dental Procedure Education System (DPES), is a web-based resource containing a collection of procedures from the dental disciplines. The procedures presented in DPES were developed by individual faculty members at the Faculty of Dentistry, University of Toronto, in collaboration with a group of educational media and technology experts. Consequently, DPES reflects the philosophy that guides the teaching methods and the clinical practice of these procedures at the Faculty of Dentistry.
Purpose:
DPES was designed and built to serve primarily the instructional needs of the students at the Faculty of Dentistry, University of Toronto. However, due to the public ramifications of the act of providing dental health care, a public extension to DPES was also developed. DPES has multiple purposes, which can be summarized as follows: It allows the students to visualize procedures through an easily accessible web-based interface; It provides a link between the didactical and clinical segments of the students' education at the Faculty; It acts as a constant resource of pertinent and academically relevant information on dental procedures, thus enhancing the quality of learning at the Faculty; It may be used by students before a treatment session to review procedural steps that need to be performed on a patient; It facilitates the students' development of their communication skills, in order for them to establish a better rapport with their patients; It provides patients with advance information about the procedure(s) for which they are scheduled. Thus, it facilitates the process of obtaining informed consent from patients for the procedure(s) they are about to undergo; It serves as a public repository of information for general purpose dental care education.
Structure:
Given the purposes outlined above, DPES is divided in two distinct parts: A patient version (DPES), open to the public, and; A student version (DPES Pro), restricted only to the students, faculty and staff of the Faculty of Dentistry, University of Toronto.The following two sections of this article describe in more detail the features of and differences between the two versions of DPES.
Structure:
DPES The public version, going by the same title as the parent program (DPES) is provided by the Faculty of Dentistry as an open source of information and dental care education. It is targeted in equal measure to the Faculty's patients and to the rest of the public. As such, DPES uses simple language to explain the steps involved in the performance of a specific dental procedure.
Structure:
Patients are provided with a visual presentation of the procedure, which employs a combination of 3D animations, actual video footage and still images to illustrate those steps. In addition, a written article describing the procedure is placed under the visual presentation. Where applicable, the article details some of the concepts presented visually or provides the patient with further relevant information, such as post-operative care or follow-up visits.
Structure:
Because the patients can be instructed by their dentists to view the procedures in advance, the patients may gain a better understanding of the various aspects involved in a particular procedure. Thus, DPES may contribute to reducing the patients' pre-operative anxiety levels and to expediting the informed consent process.
Finally, depending on the procedure involved, a patient may review online the dentist's post-operative recommendations included in the visual presentation or in the written article.
Structure:
DPES Professional DPES Professional, or DPES Pro, is intended primarily for the education of the Faculty of Dentistry's students in the undergraduate Doctor of Dental Surgery program (DDS) and it is not open to the public. As is the case with the patient version, DPES Pro uses the same combination of high-end visuals to demonstrate the techniques and methods of conducting a procedure. However, the language used in DPES Pro differs from the patient version in that the terminology is geared toward dental practitioners. The visual demonstration is normally longer than that in the patient version and, thus, it is divided into chapters for easy access to specific parts of the presentation.
Structure:
The written article that accompanies the visual presentation provides an extended scholarly explanation of the procedure, by including sections such as preliminary background or historical information about the procedure, recent research findings and their clinical implications, competing views about procedural techniques or methods, contentious or controversial issues regarding the procedure, etc. True to academic form, the article contains a list of references used in the body of the text. Thus, the student has access to the most recent literature that the author of the article considers relevant for a specific procedure.
Production:
DPES procedures follow a well-defined production cycle before they are published. The first step involves the drafting of an article for the procedure in DPES Pro by a faculty member or several faculty members of the Faculty of Dentistry. In normal circumstances, the same faculty member(s) will also be the one(s) teaching the procedure. The article is posted internally to the online repository. Once the article is drafted, it is submitted to two other faculty members for review.
Production:
Upon the completion of the review process, the author extracts the procedural section of the article and writes two separate scripts that will serve as the narrations for the visual parts of the procedures in DPES Pro and DPES, respectively. The visual presentation for DPES Pro is then assembled by the media team according to the script and with the input of the author. As soon as the visual elements are created and assembled, the author performs a final review of the visual presentation. Once the visual presentation is approved by the author, it is placed at the top of the written article in DPES Pro.
Production:
The visual presentation for DPES (public version) is created from the visual material already developed for DPES Pro. However, the public version is generally shorter and its script uses plain terms to explain the procedure. In the case of DPES, the script may also serve as the written article for the procedure, but the author may choose to extend it, annotate it or to create an entirely new article to be placed under the visuals.
Production:
When the two versions of the procedures are completed and approved, they are published and released to their particular audiences. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Pétanque**
Pétanque:
Pétanque (French pronunciation: [petɑ̃k] (listen), locally in Provence [peˈtãᵑkə]; Occitan: petanca, [peˈtaŋkɔ] (listen), also Catalan: [pəˈtaŋkə] or [peˈtaŋka]) is a sport that falls into the category of boules sports (along with raffa, bocce, boule lyonnaise, lawn bowls, crown green bowling). In these sports, players or teams play their boules/balls towards a target ball. In pétanque the objective is to score points by having boules closer to the target than the opponent after all boules have been thrown. This is achieved by throwing or rolling boules closer to the small target ball, officially called a jack (French: cochonnet), or by hitting the opponents' boules away from the target, while standing inside a circle with both feet on the ground. The game is normally and best played on hard dirt or gravel. It can be played in public areas in parks or in dedicated facilities called boulodromes.
Pétanque:
The current form of the game was codified in 1907 or 1910 in La Ciotat, in Provence, France. The French name pétanque (borrowed into English, with or without the acute accent) comes from petanca in the Provençal dialect of the Occitan language, deriving from the expression pè tancat [ˈpɛ taŋˈkat], meaning 'foot fixed' or 'foot planted' (on the ground).
History:
Invention of the game Boules games have a very long history, dating back through the Middle Ages to ancient Rome, and before that to ancient Greece and Egypt.
History:
In France in the second half of the 19th century, a form of boules known as jeu provençal (or boule lyonnaise) was extremely popular. In this form of the game, players rolled their boules or ran three steps before throwing a boule. Pétanque originally developed as an offshoot or variant of jeu provençal in 1910, in what is now called the Jules Lenoir Boulodrome in the town of La Ciotat near Marseilles. A former jeu provençal player named Jules Lenoir was afflicted by rheumatism so severe that he could no longer run before throwing a boule. In fact, he could barely stand. A good friend named Ernest Pitiot was a local café owner. In order to accommodate his friend Lenoir, Pitiot developed a variant form of the game in which the length of the pitch or field was reduced by roughly half, and a player, instead of running to throw a boule, stood, stationary, in a circle. They called the game pieds tanqués, "feet planted" (on the ground), a name that eventually evolved into the game's current name, pétanque.The first pétanque tournament was organized by Ernest Pitiot, along with his brother Joseph Pitiot, in 1910 in La Ciotat. The game spread quickly and soon became the most popular form of boules in France.
History:
Before the mid-1800s, European boules games were played with solid wooden balls, usually made from boxwood root, a very hard wood. The late 1800s saw the introduction of cheap mass-manufactured nails, and wooden boules gradually began to be covered with nails, producing boules cloutées ("nailed boules"). After World War I, cannonball manufacturing technology was adapted to allow the manufacture of hollow, all-metal boules. The first all-metal boule, la Boule Intégrale, was introduced in the mid-1920s by Paul Courtieu. The Intégrale was cast in a single piece from a bronze-aluminum alloy. Shortly thereafter, Jean Blanc invented a process of manufacturing steel boules by stamping two steel blanks into hemispheres and then welding the two hemispheres together to create a boule. With this technological advance, hollow all-metal balls rapidly became the norm.
History:
Global spread of the game After the development of the all-metal boule, pétanque spread rapidly from Provence to the rest of France, then to the rest of Europe, and then to Francophone colonies and countries around the globe. Today, many countries have their own national governing bodies.
In France, the Fédération Française de Pétanque et Jeu Provençal (FFPJP) has over 300,000 licensed members.
There are strong national federations in Germany, Spain and England. Pétanque is actively played in many nations with histories of French colonial influence, especially in Southeast Asia, including Laos, Thailand, Vietnam, Cambodia and Puducherry in India, as well as some parts of Africa. The sport is also popular in Madagascar and Thailand.
History:
Pétanque was featured at the 2015 All-Africa Games hosted by the Republic of the Congo, a former French colony.Pétanque is not widely played in the Americas. There is a Canadian pétanque federation based in Québec. In the United States, the Federation of Pétanque USA (FPUSA) reports that about 30,000 play nationwide. As of 1 December 2015, FPUSA counted 2141 members in the US, in 52 affiliated clubs.On the international level, the governing body of pétanque is the Fédération Internationale de Pétanque et Jeu Provençal (FIPJP). It was founded in 1958 in Marseille and has almost 800,000 members as of 2022.
History:
In popular culture The game made an appearance in the 1966 French crime film Le deuxieme souffle. Pétanque also appeared in Season 4 Episode 20 (Pétanque) of the American sitcom The Cosby Show in 1988. In the 1981 film adaptation of the Agatha Christie mystery Evil Under the Sun, a suspect played by James Mason is questioned about his alibi while playing a game. The fourth episode of The Amazing Race 30 featured a pétanque competition at Place des Lices in Saint-Tropez. Asterix Versus Caesar features the Gauls playing a pétanque-esque game with rocks.
History:
National and international competitions There are a number of important world championship tournaments.
History:
The FIPJP world championships take place every two years. Men's championships are held in even-numbered years, while Women's and Youth championships are held in odd-numbered years.Perhaps the best-known international championship is the Mondial la Marseillaise à Pétanque, which takes place every year in Marseille, France, with more than 10,000 participants and more than 150,000 spectators.The largest annual tournament in the United States is the Petanque Amelia Island Open (formerly the Petanque America Open), held in each year in November at Amelia Island, Florida.
History:
La British Open is a major Pétanque tournament held in the North of England which attracts players from across the United Kingdom and Europe.
History:
Pétanque is not currently an Olympic sport, although the Confédération Mondiale des Sports de Boules—which was created in 1985 by several international boules organizations specifically for this purpose—has been lobbying the Olympic committee since 1985 to make it part of the summer Olympics. Pétanque has appeared in every edition of The World Games from 1985 onward. The 2022 World Games in the United States will include women’s pétanque, the first time that only women's events will be held as part of the boules sports programme at The World Games.
Playing the game:
Based on the rules of the Fédération Internationale de Pétanque & Jeu Provençal.
Equipment Pétanque is played by two teams, each comprising one, two, or three players. In the singles and doubles games, each player plays with three metal boules. In triples, each player uses only two.
Playing the game:
The area where a game of pétanque is played is called a terrain. A game can be played in an open area such as a public park, where the boundaries of the terrain are not marked, or more formally on a "marked terrain" where the terrain boundaries are marked (traditionally, by strings tightly strung between nails driven into the ground).
Playing the game:
In pétanque, players throw while standing in a circle (cercle). Traditionally, this was simply scratched in the dirt. From around 2005, red plastic "prefabricated" circles were introduced and are now widely used in formal games. A circle drawn on the ground must be 35–50 cm (14–20 in) in diameter, while a plastic circle must have an inside diameter of 50 cm (20 in).
Playing the game:
The "ends" A game consists of several "ends" (mènes). An end consists of the throwing out of the jack (cochonnet, the little wooden target ball), followed by the two teams throwing their boules. After both teams have thrown all of their boules, the team with the boule closest to the jack wins the end. The winning team scores one point for each of its boules that is closer than the opposing team's closest boule. That means that the winning team could in theory score as many as six points in an end, although a score of one or two points is more typical. As the game progresses, each team accumulates points until one of the teams reaches 13, the winning number of points.
Playing the game:
Order of play A game begins with a coin toss to determine which team plays first. The team that wins the toss begins the game by placing the circle, then standing in the circle and throwing the jack to a distance of 6–10 metres (20–33 ft). A player from the team that threw the jack throws the first boule. Then a player from the opposing team throws a boule. From that point on, the team with the boule that is closest to the jack is said to "have the point". The team that does not have the point throws the next boule. That team continues to throw boules until it either gains the point, or runs out of boules.
Playing the game:
If at any point the closest boules from each team are equidistant from the jack, then the team that threw the last boule throws again. If the boules are still equidistant then the teams play alternately until the tie is broken. If the boules are still equidistant at the end of the mène then neither team scores any points.
The team that won the end starts the next end. A player from the winning team places (or draws) a circle around the jack. The player then picks up the jack, stands in the circle, and throws the jack to start the next end.
Scoring An end is complete when both teams have played all of their boules, or when the jack is knocked out of play (goes "dead").
If the end finishes in the usual way—with the jack still live and one team with the closest boule—then the team with the closest boule wins the end and scores one point for each of its boules that is closer to the jack than other team's closest boule.
Playing the game:
If the jack is live but there is an "equidistant boules" situation at the end of the mène, then neither team scores any points. If the jack is dead at the finish of the end, then if one (and only one) team still has boules left to play, that team scores one point for each boule that it still has in hand. Otherwise neither team scores any points in the end (like an inning in baseball in which neither team scores any runs).
Playing the game:
Miscellaneous rules Boules can be thrown in any way that the player wishes, but the traditional way is to hold the boule with the palm of the hand downwards, and then to throw with an under-arm swing of the arm ending in an upward flick of the wrist. Throwing this way puts backspin on the boule and gives the player the maximum amount of control and flexibility when throwing.
Playing the game:
The boule can be rolled, thrown to a moderate height, or even thrown to a great height (a high lob or portée).
Players usually carry a tape measure for measuring close points.
At the beginning of an end, before throwing the jack, if there isn't enough room for the player to throw the jack to the maximum legal distance of 10 metres (33 ft), then the player is allowed to move the circle back to a point where there is enough room.
On a terrain with boundaries marked with strings, a boule or jack must completely cross the boundary string before it is considered to be out-of-bounds and dead.
Equipment specifications:
Boules Leisure boules are boules that do not meet the FIPJP standards for competition boules, but are less expensive than competition boules and completely adequate for "backyard" games. Unlike competition boules, leisure boules are a "one size fits all" affair—they come in one weight and size.
Equipment specifications:
Competition boules must meet specifications set by the FIPJP. They must be hollow and made of metal (usually steel) with a diameter between 70.5 and 80 mm (2.78 and 3.15 in) and a weight between 650 and 800 g (23 and 28 oz). When purchasing competition boules, a purchaser has a choice of a number of characteristics, including the size, weight, and hardness of the boules, as well as the striations (patterned grooves on the surface of the boules).
Equipment specifications:
Jack The jack, or target ball, is a small ball made of wood, traditionally boxwood or beechwood, 30 mm (1.2 in) in diameter. In the past, jacks were often left "natural"—unfinished or with a clear finish—but nowadays they are often painted in bright colours. In French, the jack is known by a variety of names, including but (goal or target), cochonnet (piglet), bouchon ("little ball" in provençal language, not related to the French word "bouchon" that designates a bottle stopper), le petit (the little one), and gari ("rat", also in provençal language).
Equipment specifications:
Playing area Pétanque can be played on almost any flat, open space. The ground may be irregular and interrupted by trees or rocks, and the surface is likely to be uneven, with some areas hard and smooth and other areas rough and stony. When an area is constructed specifically for the purposes of playing pétanque, the playing surface is typically loose gravel, decomposed granite, brick grog or crushed sea shell. Sandy beaches are not suitable, although light plastic boules are sometimes used to adapt the game for the beach. There is no requirement for backboards or sideboards (as in bocce), but dedicated playing areas are often enclosed in boards or some other structural barrier.
Equipment specifications:
In France, village squares and park pathways are often used as pétanque playing areas. In addition, many towns have recreational facilities (boulodromes) constructed specifically for playing pétanque.
Equipment specifications:
An area where a single pétanque game is played is called a terrain. A "playing area" (aire de jeu) is an area containing one or more terrains. For tournaments, a large playing area is subdivided and marked off (typically using nails and string) into rectangular marked terrains (also known as "lanes" (cadres) or "pistes") so that multiple games may be carried on simultaneously. For tournament play, a marked terrain is a rectangle at least 4 metres (13 ft) wide and 15 metres (49 ft) long.
Strategy:
Pointing and shooting Generally speaking, a player throws a boule with one of two objectives: To make the boule come to rest in a particular spot, usually as close as possible to the jack. This is called pointing.
Strategy:
To make the boule directly hit an opponent's boule with the aim of knocking it away from the jack. This is called shooting.The best throw is called a carreau. It is a shot that knocks away the opponent's boule, leaving the thrown boule exactly in its place.Players who are skilful enough to shoot effectively are called 'shooters' (tireurs); players who usually point are called 'pointers' (pointeurs) As a matter of strategy, pointers play first and shooters are held in reserve in case the opponents place well. Good pointing is what scores points, but national and international championships are usually dominated by skilful shooters, who target any opposing boule that comes close to scoring.
Strategy:
Throwing a boule Some strategic considerations involved in the throw of a boule include: A traditional maxim is boule devant, boule d'argent ("A ball in front is a money ball."). A boule located closer to the player than the jack ("in front of the jack") is much more valuable than one behind the jack. A boule in front blocks the opposing team from easy access to the jack, and it may also (intentionally or accidentally) be hit and pushed closer to the jack.
Strategy:
If a player points a boule very close to the jack, it forces the opposing shooter to shoot it immediately. This may prove to be a disadvantage to a pointer who wants to keep that boule, or it can be advantageous if the pointer is trying to force the opposing shooter to exhaust their supply of boules.
It is generally a bad idea for a player to shoot with their team's last boule. In most cases, the better strategy is to "limit the damage" by pointing the team's last boule close enough to the jack to limit the opposing team's gains to a single point.
Throwing the jack Strategic considerations involved in the throw of the jack include: Throw the jack to a distance at which your own shooter is most comfortable, or the opposing shooter is least comfortable.
Aim for a location on the terrain that your own pointers prefer, or that might be difficult for the opposing team's pointers.
Disorient the opposing team by refusing to get in a rut. At each opportunity, throw the jack to a new position on the terrain, and alternate long and short distances.
Glossary of special terms:
In the following glossary, the French word or phrase is given in brackets unless it is the same: join battle (arriver a bataille). When both teams have 10 or 11 points and the game may go either way on each lead.
bombard. To shoot or strike an opponent's boules one after another, after they had taken the lead.
boule devant, boule d'argent. "A ball in front is a money ball". This maxim reminds players that when pointing, the most valuable place for a boule is in front of the jack. In that location, it prevents opponents from throwing directly toward the jack, and hitting it will push it even closer to the jack.
jack (but, also bouchon, cochonnet, petit, gari or kiki). The small wooden or plastic target ball.
carambolage Shot that knocks away several boules. Literally "pile-up".
circle (cercle or rond). The marked area from within which the boules are thrown.
demarquer ("unscore"). To drop a point when pointing or shooting.
fuser. A boule that bounces off course.
have the point. A team is said to "have the point" if one of its boules is closer to the jack than any of the opposing team's boules. A team that has the point is basically in a winning position, so the team that does NOT have the point throws the next boule and attempts to gain the point.
mene. "End" i.e. the period of play from the throw of a jack to the point when both teams have played all their boules.
point To throw one's boule with the intent of stopping near the jack (also known as placing). Video: 20 best points from the Masters de Pétanque 2017 pousette. A shot that pushes one's team's boules nearer the jack; or to that pushes the jack.
Glossary of special terms:
shoot To throw one's boule at an opponent's boule (or at the jack) in an attempt to knock it out of play. When the opposing team has a boule positioned very close to the jack, often the best strategy is to attempt to shoot it. A team in a desperate situation may attempt to save itself by shooting the jack out of bounds. Video: 20 best shots from the Masters de Pétanque 2017 lob (portée) A boule thrown in a high arc so that when it lands it only rolls a short distance. Video: Marco Foyot demonstrates the high lob.
Glossary of special terms:
carreau (pronounced carrow). A shot that knocks an opposing boule away from the jack and replaces it (in very nearly the same spot) with the thrower's own boule. Basically, the perfect shot. Video: Diego Rizzi demonstrates a perfect carreau.fanny (mettre fanny). To lose a game without scoring any points; a shutout game. When a player loses 13 to 0, he is said to fanny ("il est fanny", he's fanny, or "il a fait fanny", he made fanny) and must kiss the bottom of a girl named Fanny. Virtually everywhere in Provence where pétanque is played, you will find a picture, woodcarving, or pottery figure of a bare-bottomed young woman named Fanny. Often, the team that "made fanny" has to buy a round of drinks for the winning team ("Fanny paie à boire !", "the fanny pays for the drinks!"). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Rough number**
Rough number:
A k-rough number, as defined by Finch in 2001 and 2003, is a positive integer whose prime factors are all greater than or equal to k. k-roughness has alternately been defined as requiring all prime factors to strictly exceed k.
Examples (after Finch):
Every odd positive integer is 3-rough.
Every positive integer that is congruent to 1 or 5 mod 6 is 5-rough.
Every positive integer is 2-rough, since all its prime factors, being prime numbers, exceed 1. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Skipper (computer software)**
Skipper (computer software):
Skipper is a visualization tool and code/schema generator for PHP ORM frameworks like Doctrine2, Doctrine, Propel, and CakePHP, which are used to create database abstraction layer.
Skipper is developed by Czech company Inventic, s.r.o. based in Brno, and was known as ORM Designer prior to rebranding in 2014.
Overview:
Generates visual model from the schema definition files Repetitive import/export of schema definitions in supported formats (XML, YML, PHP annotations) Schema definition files are automatically generated from the visual model Visual representation uses ER diagram extended by concepts of inheritance and many-to-many Supports customization using .xml configuration files and JavaScript Does not support direct connections to the database Crude and simplistic visual representation and menus
Architecture:
Skipper was built on the Qt framework. Import/export of the schema definitions uses XSL transformations powered by LibXslt library. Imported source files are first converted to XML format: no conversion for XML, simple conversion for YML, creating the Abstract Syntax Tree and its subsequent conversion to XML for PHP annotations.
The import/export scripts are configured in JavaScript and can be freely customized.
Supported ORM frameworks:
Frameworks supported for visual model and schema files generation: Doctrine2 Doctrine Propel CakePHP
History:
Skipper was created as an internal tool for the web applications developed by Inventic. It was first published as a commercial tool under the name ORM Designer in 2009.
Application was reworked and optimized in January 2013, and released as ORM Designer 2.
In May 2013 ORM Designer became part of the South Moravian Innovation Center Incubator program (support program for innovative technological startups).
In June 2014, ORM Designer version 3 was released and rebranded under the name of Skipper | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Benzophenone imine**
Benzophenone imine:
Benzophenone imine is an organic compound with the formula of (C6H5)2C=NH. A pale yellow liquid, benzophenone imine is used as a reagent in organic synthesis.
Synthesis:
Benzophenone imine can be prepared by the thermal decomposition of benzophenone oxime: 2 (C6H5)2C=NOH → (C6H5)2C=NH + (C6H5)2C=OBenzophenone imine can also be synthesized by addition of phenylmagnesium bromide to benzonitrile followed by careful hydrolysis (lest the imine be hydrolyzed): C6H5CN + C6H5MgBr → (C6H5)2C=NMgBr (C6H5)2C=NMgBr + H2O → (C6H5)2C=NH + MgBr(OH)This method is known as Moureu-Mignonac ketimine synthesis. Yet another route to benzophenone imine involves reaction of benzophenone and ammonia.
Reactions:
Benzophenone imine undergoes deprotonation with alkyl lithium reagents.
(C6H5)2C=NH + CH3Li → (C6H5)2C=NLi + CH4 (C6H5)2C=NLi + CH3I → (C6H5)2C=NCH3 + LiIPrimary amines can be protected as benzophenone imines, and the protected amines are stable in flash chromatography.Buchwald-Hartwig amination involves coupling aromatic halide and amine to form carbon-nitrogen bonds with the help of palladium-based catalysts. Benzophenone imine can be used as an ammonia-equivalent in such reactions. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**2,6-dihydroxypyridine 3-monooxygenase**
2,6-dihydroxypyridine 3-monooxygenase:
In enzymology, a 2,6-dihydroxypyridine 3-monooxygenase (EC 1.14.13.10) is an enzyme that catalyzes the chemical reaction 2,6-dihydroxypyridine + NADH + H+ + O2 ⇌ 2,3,6-trihydroxypyridine + NAD+ + H2OThe 4 substrates of this enzyme are 2,6-dihydroxypyridine, NADH, H+, and O2, whereas its 3 products are 2,3,6-trihydroxypyridine[1], NAD+, and H2O.
2,6-dihydroxypyridine 3-monooxygenase:
This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with NADH or NADPH as one donor, and incorporation of one atom o oxygen into the other donor. The systematic name of this enzyme class is 2,6-dihydroxypyridine,NADH:oxygen oxidoreductase (3-hydroxylating). This enzyme is also called 2,6-dihydroxypyridine oxidase. It has 2 cofactors: FAD, and Flavoprotein. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Myricetin O-methyltransferase**
Myricetin O-methyltransferase:
In enzymology, a myricetin O-methyltransferase (EC 2.1.1.149) is an enzyme that catalyzes the chemical reaction 2 S-adenosyl-L-methionine + myricetin ⇌ 2 S-adenosyl-L-homocysteine + syringetinThus, the two substrates of this enzyme are S-adenosyl methionine and myricetin, whereas its two products are S-adenosylhomocysteine and syringetin.
This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:myricetin O-methyltransferase. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Eva (Metal Gear)**
Eva (Metal Gear):
The Metal Gear franchise features a large number of characters created by Hideo Kojima and designed by Yoji Shinkawa. Its setting features several soldiers with supernatural powers provided by the new advancements of science.
Eva (Metal Gear):
The series initially follows mercenary Solid Snake given government missions of finding the Metal Gear weapon, resulting in encounters in the original Metal Gear games with Gray Fox and Big Boss in Outer Heaven and Zanzibar Land, as well as the original Metal Gear Solid games working with Otacon and Raiden while opposing Liquid Snake's FOXHOUND, Solidus Snake, the Patriots and Revolver Ocelot. Additionally, the Metal Gear Solid prequels follow Big Boss's past as Naked Snake and legend development via Venom Snake as well as the origins of the various aforementioned organizations.
Eva (Metal Gear):
While the original Metal Gear games had their characters designs modeled after Hollywood actors, the Metal Gear Solid games established a series of consistent designs based on Shinkawa's ideas of what would appeal to gamers. Additionally, several of the characters he designs follow Kojima and the other staff's ideas. Critical reception of the game's cast has been positive as publications praised their personalities and roles within the series.
Creation and designs:
Much as Metal Gear began as a pastiche of action movies of the time, characters were pastiches of contemporary action movie heroes. Once Yoji Shinkawa started designing the characters in PlayStation's Metal Gear Solid, they were given their respective established visual appearances. As a result of the console's limitations, Shinkawa designed them an idea that would appeal to gamers. Because of the timeskip between titles, a few of the characters have been redesigned to fit in the game's year. With the improvements from new video game consoles like the PlayStation and PlayStation 2, the staff gave the characters a more realistic look starting with Metal Gear Solid 2: Sons of Liberty although they initially had doubts about it. This brought difficulties to the staff as they had to make the faces more realistic. When illustrating characters, Shinkawa does not focus on their minor details, such as the eyes which he sometimes does not try to draw, instead illustrating something more symbolic. While Solid Snake remained easy to illustrate as a result of him having a consistent design to the point Big Boss' younger self, Naked Snake, was conceived making minor changes to the original version of Solid Snake, other characters were more time-consuming owing.During their debuts, player-characters Solid Snake and Raiden are meant to represent the player while in the following titles they acquire more defined personalities. As a result of the Snake's increasing experience in combat across the series, Kojima attempted creating more challenging antagonists for the boss battles. This resulted in Big Boss' clones from Metal Gear Solid and Metal Gear Solid 2 that had the same abilities as Solid Snake, the legendary Cobra Unit from Metal Gear Solid 3: Snake Eater who participated in World War II and the Beauty and the Beast Corps from Metal Gear Solid 4: Guns of the Patriots that had few human traits. While villains during the first games were given detailed backstories, the Cobra Unit members were intended to have little information known about them, resulting in a significant impact in the gamers upon their deaths following their boss battles. This gave Shinkawa difficulties in conceptualizing their visual appearances as a result of having little to no background details. By Metal Gear Solid 2, Kojima was inspired by the Sherlock Holmes novels to introduce a sidekick character in order to view Snake from a different perspective.Metal Gear Solid also marks the first time that characters were given voice actors with Solid Snake and Naked Snake being voiced by Akio Ōtsuka. Ōtsuka remembers being surprised during his debut as a result of the large amount of dialogue Snake was given. In the English adaptations, the casting was directed by Kris Zimmerman and supervised by a member from Konami. Solid Snake's voice actor was David Hayter who, despite having issues with some of the dialogue in Metal Gear Solid, became attached to the series.Various Metal Gear Solid games have remade/expanded upon by titles, such as Metal Gear Solid: The Twin Snakes, Metal Gear Solid: Digital Graphic Novel, Metal Gear Solid 2: Digital Graphic Novel, and Metal Gear Online.
Introduced in Metal Gear:
Solid Snake Solid Snake (ソリッド・スネーク, Soriddo Sunēku), real name David (デイビッド, Deibiddo), is the primary character of the original series. In the original Metal Gear games, he's a rookie member from FOXHOUND given the mission to find and destroy the Metal Gear located within Outer Heaven and Zanzibar Land, leading to confrontations with his comrade Gray Fox both times, as well as Big Boss (the phantom in Outer Heaven and his superior in Zanzibar Land). In the original Metal Gear Solid games, Snake gains a friendship with Otacon while fighting a corrupt FOXHOUND led by his terrorist twin Liquid Snake in Metal Gear Solid, and uses the false name Iroquois Pliskin (イロコィ・プリスキン, Irokoi Purisukin) while assisting Raiden against Solidus Snake and the Patriots in Metal Gear Solid 2: Sons of Liberty. In Metal Gear Solid 4: Guns of the Patriots, he gives himself the nickname Old Snake (オールド・スネーク, Ōrudo Sunēku) due to his accelerated aging process and is the playable character once more. Solid Snake is voiced by Akio Ōtsuka in the Japanese version and by David Hayter in the English translation.
Introduced in Metal Gear:
Big Boss Big Boss (ビッグ・ボス, Biggu Bosu) is the greatest soldier who ever lived. The Metal Gear Solid games gradually reveal the character to be two individuals: Naked Snake after defeating his legendary war hero mentor, and Venom Snake as a body double.
Introduced in Metal Gear:
Gray Fox Gray Fox (グレイ・フォックス, Gurei Fokkusu, spelled "Grey Fox" in the MSX2 versions) first appears in the MSX2 games as a high-ranking agent of FOXHOUND as the "Fox" codename being the highest distinction within the unit. His face portrait in the MSX2 version was modeled after actor Tom Berenger. Prior to the game's events, he goes missing during a mission to Outer Heaven with his last transmission being a cryptic message simply saying "Metal Gear". Fox is later rescued by Solid Snake, and reveals TX-55 Metal Gear's true nature to the player.
Introduced in Metal Gear:
Metal Gear 2: Solid Snake revealed that Gray Fox left FOXHOUND and defected to Zanzibar Land. Fox pilots the advanced model Metal Gear D and confronts Solid Snake a few times, while secretly assisting Snake as an anonymous informant. The character's past is fleshed out in this game: his civilian identity Frank Jaeger (フランク・イェーガー, Furanku Yēgā, "Frank Yeager" in the MSX2 version) had a relationship with former Czech figure skater Gustava Heffner (Natasha Marcova in the MSX2 version) after they met in Calgary and fell in love. Gustava tried to seek asylum with him in America, but failed and was stripped of competition rights as a result. Following this incident, Jaeger developed a great deal of resentment toward his superiors, but was unaware that Gustava later joined the StB and is present in Zanzibar as Dr. Kio Marv's bodyguard. During his and Snake's first direct encounter as enemies, Fox's piloting of the Metal Gear accidentally causes Gustava's death. After Snake destroys Metal Gear, Fox challenges Snake to a fistfight in the middle of a minefield and is apparently killed.
Introduced in Metal Gear:
Gray Fox returns as the original Cyborg Ninja (サイボーグ忍者, Saibōgu Ninja) in Metal Gear Solid after he has been grafted into a powered armor exoskeleton and armed with a high-frequency blade. According to Hideo Kojima, the Cyborg Ninja "was born from this Shin-chan's graffiti." During Liquid Snake's FOXHOUND revolt of Shadow Moses, Fox once again challenges Solid Snake to a fight, maiming Revolver Ocelot and scaring Otacon in the process. After the fight, he becomes erratic and disappears in a violent rage. Throughout the game, he provides Snake cryptic advice via CODEC as a faceless contact calling himself "Deepthroat". Naomi Hunter eventually divulges being Jaeger's foster sister as well as his Cyborg Ninja identity to Snake. Fox later tells Snake that he killed Naomi's parents and, feeling remorse, became her foster brother. Fox fights Metal Gear REX and manages to destroy its radome with the use of a prototype railgun attached to his arm. However, Fox is mortally wounded and begs Snake to kill him and destroy REX with a stinger, but Snake refuses to shoot. Saying goodbye to his comrade, he is killed by Liquid (piloting REX).
Introduced in Metal Gear:
Raiden initially thought that the Cyborg Ninja in Metal Gear Solid 2: Sons of Liberty seen during Solidus Snake's Manhattan incident was Gray Fox before learning that the person in question is actually Olga Gurlukovich.
Introduced in Metal Gear:
The second prequel Metal Gear Solid: Portable Ops (set twenty-five years before Metal Gear) featured a teenage version of the character under the codename Null (ヌル, Nuru), a masked machete-wielding assassin. He is subjected to a secret CIA project to be the "Perfect Soldier" and recruited into Gene's corrupt FOX unit during the San Hieronymo takeover. During the game, Null fights with Naked Snake twice. Snake eventually realized that Null was a boy in Mozambique that used his innocence as a cover to kill dozens of government soldiers with only one knife while speaking a little German, thus how he was deemed "Frank Jaeger" (German for "Frank Hunter"). Snake defeated Jaeger and sent him to somewhere outside of FOX for help.
Introduced in Metal Gear:
Metal Gear Solid 4: Guns of the Patriots reveals that Frank Jaeger's murder of Para-Medic was part of Big Mama's plan to free Big Boss from Zero's control.
There is a Cyborg Ninja unique character card in Metal Gear Acid. Outside of the Metal Gear games, the Cyborg Ninja is featured as a player character driver in Konami Krazy Racers and as an Assist Trophy in both Super Smash Bros. Brawl and Super Smash Bros. Ultimate.
In 2013, Kojima stated to be interested in developing a game with Gray Fox as the main playable character, although Kojima does not assure it to happen.The character's Cyborg Ninja exoskeleton appears as a downloadable content skin for Raiden in Metal Gear Rising: Revengeance, and Venom Snake in Metal Gear Solid V: The Phantom Pain.
Introduced in Metal Gear:
Dr. Madnar Dr. Drago Pettrovich Madnar (ドラゴ・ペトロヴィッチ・マッドナー, Dorago Petorovitchi Maddonā, known simply as Dr. Petrovich in the original Metal Gear and Dr. Pettrovich Madnar in the MSX2 version of Metal Gear 2) is an Eastern engineer responsible for creating the TX-55 Metal Gear mecha in the original Metal Gear, as well as the TX-11 Arnold (Bloody Brad) androids. Dr. Madnar is one of the hostages Snake must rescue along with his daughter Ellen (エレン, Eren). In Metal Gear 2, Dr. Madnar bitterly defects to Zanzibar Land and develops Metal Gear D after being rejected by the scientific community. He comes in contact with Snake in the game while posing as a hostage, but attacks him after the truth is revealed. His name is mentioned in Metal Gear Solid 4 as the scientist who saved Raiden's life after being turned into a cyborg. A character with the same name also plays a supporting role in Hideo Kojima's adventure game Snatcher, although the English-language version for the Sega CD spells his name as Dr. Petrovich Modnar.
Introduced in Metal Gear:
Kyle Schneider Kyle Schneider (カイル・シュナイダー, Kairu Shunaidā) (known simply as Schneider in the original Metal Gear) is the leader of a resistance movement against Outer Heaven in Metal Gear, who helps Solid Snake as a radio contact alongside fellow resistance members Diane (ダイアン, Daian) and Jennifer (ジェニファー, Jenifā). He discovers the identity of Outer Heaven's leader, but is silenced before he can mention his name. In Metal Gear 2, Schneider appears under the guise of Black Ninja (ブラック・ニンジャ, Burakku Ninja) (Black Color (ブラック・カラー, Burakku Karā) in the original MSX2 version), a high-tech ninja under the service of Zanzibar Land and the first boss in the game. Solid Snake defeats him during a battle but does not learn his true identity until he collapses. He then reveals to Snake that NATO led a bombing raid against Outer Heaven, not caring about the war orphans or war refugees. Before dying, he also tells Snake that Big Boss had forgiven the resistance for being against him and rescued as many people as he could from the bombings, Outer Heaven personnel and Resistance members alike.
Introduced in Metal Gear 2: Solid Snake:
Roy Campbell Col. Roy Campbell (ロイ・キャンベル大佐, Roi Kyanberu Taisa, Roy Kyanbel in the MSX2 version of Metal Gear 2) is the second commanding officer of FOXHOUND.Introduced in Metal Gear 2, he serves as Solid Snake's primary radio contact in the game and gives information about the mission objective and general gameplay tips for Zanzibar Land. In Metal Gear Solid, Campbell has more of a personal stake in the mission on Shadow Moses, as his niece Meryl Silverburgh is held captive by Liquid Snake's revolutionary FOXHOUND. In one of the game's endings, he reveals Meryl is his daughter, the result of an affair between himself and his late brother's wife. In Metal Gear Solid 2, he is impersonated by the "Colonel", Raiden's commanding officer that provides support via codec that's later revealed to be an elaborate AI constructed by supercomputer GW within Arsenal Gear for the Patriots.Although he is not involved in the main story, the character makes a voice only cameo in Metal Gear Solid 3 during the game over screen scolding the player for causing a time paradox if the player kills certain characters. He also appears in the Ape Escape crossover minigame "Snake vs. Monkey". In Portable Ops, a young version of the character is imprisoned by the FOX unit in South America with Naked Snake. The two escape to recruit Gene's disenfranchised enemy soldiers and other allies into an early version of FOXHOUND.In Metal Gear Solid 4, Campbell works for a UN Security Council advisory body that monitors PMC activities. He sends Old Snake on an unofficial mission to assassinate Liquid Ocelot in order to put a stop to, providing resources and transportation to complete the mission. He is married to Rosemary which causes a rift between him and Meryl, now aware that Campbell is her father. However, the marriage is a sham used to fool the Patriots and protect Rose's and Raiden's son John. Following the Patriots' destruction, he reconciles with Meryl to walk down the aisle at his daughter's wedding.
Introduced in Metal Gear 2: Solid Snake:
Outside the main canon, the character reprises his role as the reluctant commanding officer in the Game Boy Color game Metal Gear: Ghost Babel, a side-story which serves as an alternate sequel to the events of the original Metal Gear. He, Otacon and Mei Ling serve as Solid Snake's codec contacts in Super Smash Bros. Brawl. He also makes a brief codec appearance in a minigame in Ape Escape 3.
Introduced in Metal Gear 2: Solid Snake:
Roy Campbell for most Metal Gear Solid games has been voiced by Takeshi Aono in the Japanese version and by Paul Eiding in the English translation. His young version in Portable Ops is voiced by Toshio Furukawa in Japanese and by David Agranov in English. However, Takeshi Aono's death has caused the character's retirement in future Metal Gear Solid games out of respect.
Introduced in Metal Gear 2: Solid Snake:
Master Miller Master Miller (マスター・ミラー, Masutā Mirā) is a drill instructor and survival coach who was originally Kazuhira Miller, but is impersonated by Liquid Snake in Metal Gear Solid.
Introduced in Metal Gear 2: Solid Snake:
Kio Marv Dr. Kio Marv (キオ・マルフ, Kio Marufu) is a Czechoslovak biotechnologist. In the backstory of Solid Snake, Marv successfully creates a new algae species called OILIX that could produce petroleum-grade hydrocarbons with little expense and effort. Marv presented the algae to the World Energy Conference in Prague, and was on his way to a demonstration in the United States when he was kidnapped by soldiers from Zanzibar Land. Solid Snake is brought out of retirement by FOXHOUND's new commander, Roy Campbell, and is sent to Zanzibar Land to rescue Dr. Marv. However, he dies of torture in his cell and left behind the OILIX plans for Snake to find.
Introduced in Metal Gear 2: Solid Snake:
Holly White Holly White (ホーリー・ホワイト, Hōrī Howaito, Horry White in the original MSX2 version) is an American freelance journalist. Born from a French mother and an English father, she became interested in literature at an early age and was later awarded the Pulitzer Prize for her coverage in Afghanistan plus an Emmy Award (mistakenly referred to in the original manual as a Grammy Award) for her documentary, Unknown Bloodstream. Her newfound fame eventually gets her the attention of the CIA. She infiltrates Zanzibar Land as a journalist and assists Solid Snake over the course of the mission.
Introduced in Metal Gear 2: Solid Snake:
Gustava Heffner Gustava Heffner (グスタヴァ・ヘフナー, Gusutava Hefunā), originally named Natasha Marcova (ナターシャ・マルコバァ, Natāsha Marukobaa) in the MSX2 version of Metal Gear 2, is a former professional figure skater. Once known as one of the world's best figure skaters (with stints in the world championships and the Olympics under her belt), Heffner was stripped of her competition rights after being caught in an attempt to seek political asylum in Canada with Frank Jaeger. She sought to redeem herself by joining the StB. She is escorting Dr. Marv to America when Zanzibar Land agents hijack their plane. Later in the game, she joins Snake in rescuing Dr Marv, but dies when Jaeger (as Gray Fox in Metal Gear D) destroys the bridge she is on.
Introduced in Metal Gear 2: Solid Snake:
George Kasler George Kasler (ジョージ・ケスラー, Jōji Kesurā, George Kesler in the MSX2 version) is FOXHOUND's resident strategist and advisor whose military career includes service with mercenaries from South Africa and the French Foreign Legion, plus a short stint in negotiation and combat intelligence-gathering. He is also a veteran of the 1997 Mercenary War of Independence in Zanzibar Land, fighting the CIS Army. Kasler's service earns him a lasting reputation in the mercenary community; only mercenaries who have worked with him can be truly recognized as the best in the world.
Introduced in Metal Gear 2: Solid Snake:
Johan Jacobsen Johan Jacobsen (ヨハン・ヤコブセン, Yohan Yakobusen), named Yozev Norden (ヨゼフ・ノルデン, Yozefu Noruden) in the MSX2 version, is a zoologist specializing in the preservation of all endangered species. He is the vice-president of the fictional Worldwide Animal Rights Federation and works for the science magazine Maxwell. He is revealed to have been acquainted with Dr Madnar since their days in college and is in Zanzibar Land to study indigenous animals.
Introduced in Metal Gear Solid:
Revolver Ocelot Revolver Ocelot (リボルバー・オセロット, Riborubā Oserotto) is a recurring gunslinger antagonist during the Metal Gear Solid games. He is a major nemesis of Solid Snake during the original Metal Gear Solid games as Shalashaska (シャラシャーシカ, Sharashāshika) where's he acted as Liquid Snake's henchman within FOXHOUND during Metal Gear Solid and Solidus Snake's right-hand man and the Patriots' agent during Metal Gear Solid 2, both Naked Snake's friendly rival and the Philosophers' triple agent during Metal Gear Solid 3 as Major Ocelot (オセロット少佐, Oserotto Shōsa), the central antagonist of Metal Gear Solid 4 as Liquid Ocelot (リキッド・オセロット, Rikiddo Oserotto), and an ally of Venom Snake during Metal Gear Solid V. Playing a major role in the overall story, Ocelot's intentions during the games he appears in are shrouded in mystery, and are all to accomplish his own undisclosed intentions. In the Japanese version, Revolver Ocelot was voiced by Kōji Totani (original depiction), Takumi Yamazaki (younger version), Satoshi Mikami (middle-aged version) and Banjō Ginga (Liquid Ocelot). In the English translation, Revolver Ocelot is voiced by Patric Zimmerman (original depiction and Liquid Ocelot), Joshua Keaton (younger version) and Troy Baker (middle-aged version).
Introduced in Metal Gear Solid:
Otacon Hal Emmerich (ハル・エメリッヒ, Haru Emerihhi), nicknamed Otacon (オタコン, Otakon), is a recurring character in the Metal Gear Solid series and Solid Snake's close friend. He is introduced in Metal Gear Solid as ArmsTech's employee and Metal Gear REX's engineer that learns of REX's nuclear strike capabilities and becomes Snake's close ally. Afterwards, he's seen as founding member of the non-profit Philanthropy organization while dealing with more emotional problems in Metal Gear Solid 2: Sons of Liberty and Metal Gear Solid 4: Guns of the Patriots. Otacon is voiced by Hideyuki Tanaka in the Japanese version and by Christopher Randolph in the English translation.
Introduced in Metal Gear Solid:
Naomi Hunter Naomi Hunter (ナオミ・ハンター, Naomi Hantā), nicknamed Dr. Naomi (ドクター・ナオミ, Dokutā Naomi) by her staff as opposed to the more formal Dr. Hunter, is a geneticist by practice, and specializes in nanotechnology-based gene therapy.
Introduced in Metal Gear Solid:
In Metal Gear Solid, she is the chief of FOXHOUND's medical staff and part of the support crew assembled to assist Solid Snake, providing the player with information on the FOXHOUND members Snake faces. Being Gray Fox's adopted sister, she attempted to get revenge on Snake for nearly killing her brother during the original Metal Gear games. When instructed to inject Snake with the FOXDIE virus, she secretly modifies it so that it will kill Snake at a random moment in addition to its original programming. As the game progresses, Naomi realizes that some of her original perceptions of Snake were wrong and is later remorseful for modifying the virus. Uncertain of when exactly the FOXDIE would kill, Naomi tells Snake to live life to the fullest in whatever time there was left. Afterwards, Nastasha Romanenko's account reveals that Naomi was briefly arrested following the Shadow Moses incident until her escape.In Metal Gear Solid 4, Naomi is working with Liquid Ocelot in order to hijack the SOP battlefield control system, but joins Old Snake's group once again. She becomes romantically involved with Otacon and forms a friendship with Sunny. When they return to Shadow Moses, Naomi reveals that she has been diagnosed with terminal cancer that has been kept in check by nanomachines and, guilt-ridden over her past mistakes, commits suicide by disabling them.Naomi Hunter is voiced by Hiromi Tsuru in the Japanese version and by Jennifer Hale in the English translation.
Introduced in Metal Gear Solid:
Meryl Silverburgh Meryl Silverburgh (メリル・シルバーバーグ, Meriru Shirubābāgu) is a character based on the character of the same name from Policenauts that was redesigned and reintroduced. She is introduced in Metal Gear Solid as Solid Snake's sidekick/love interest and Roy Campbell's legal niece/biological daughter that's caught in the middle of Liquid Snake's terrorist FOXHOUND. Meryl returns in Metal Gear Solid 4: Guns of the Patriots as Rat Patrol Team One's commander. Meryl Silverburgh is voiced by Kyoko Terase in the Japanese version and by Debi Mae West in the English translation.
Introduced in Metal Gear Solid:
Mei Ling Mei Ling (美玲（メイ・リン）, Mei Rin) is a Chinese-American data analyst. In Metal Gear Solid, she is in charge of saving the player's progress. She invented Solid Snake's wireless communication system, the codec radio, as well as the Soliton Radar, which detects the positions and field of vision of nearby enemy soldiers. Every time Snake saves his data, Mei Ling provides him with advice through Chinese proverbs, as well as quotations from Western authors. In the Japanese version, Mei Ling only quoted Chinese proverbs: she would cite the original proverb in Chinese and then explain its meaning to Snake in Japanese. According to Kojima, this made some of the proverbs redundant after translating them to English, since Mei Ling would be saying the same thing twice. In Metal Gear Solid 2, Mei Ling is part of Philanthropy, an anti-Metal Gear organization, but assists off-screen, attempting to steal equipment from the SSCEN. She makes a voice-only cameo in the game as an easter egg during the Tanker chapter, after the player has saved their progress 13 times. In Metal Gear Solid 4, Mei Ling commands the museum-turned-training vessel USS Missouri and provides Old Snake and Otacon with backup, courtesy of her connections from the SSCEN.Mei Ling has made a few appearances outside the main series of Metal Gear games. She is a central character in the radio drama version of Metal Gear Solid (set after the events of the original game) and appears in the Game Boy Color version of Metal Gear Solid (a side story not clearly related to the main series). Mei Ling is also one of the support crew in Super Smash Bros. Brawl. Mei Ling is voiced by Houko Kuwashima in the Japanese version and by Kim Mai Guest in the English translation.
Introduced in Metal Gear Solid:
Johnny Sasaki Johnny Sasaki (ジョニー佐々木, Jonī Sasaki) is a recurring character.
Introduced in Metal Gear Solid:
First appearing in Metal Gear Solid, he is an enemy guard whose uniform is stolen by Meryl Silverburgh and again later in the game whilst Solid Snake is being held between torture sessions with Revolver Ocelot while suffering from a cold and diarrhea. Johnny's character is never named in the game and is listed only in the ending credits as Johnny Sasaki. The surname Sasaki comes from the game's character model designer Hideki Sasaki. According to the developers' commentary in Metal Gear Solid: Integral, Hideki was known among the staff for his slackoff behavior and the character was included in the game as a running gag.Johnny later returns for a pair of voice-over only cameos in Metal Gear Solid 2. In an early version of the game's story, his full name was to be Johnny Sasaki Slater (ジョニー・佐々木・スレイター, Jonī Sasaki Sureitā) and originally had a minor role in the story in which his character (a spy for the Patriots) would die from a pacemaker malfunction after coming in contact with Raiden. During the game, Raiden can hear Johnny talking using a directional mic in Big Shell.In the game of Metal Gear Solid 4, Johnny now has the nickname Akiba (アキバ) and is a member of Meryl's Rat Patrol Team 01. Also, his face is revealed for the first time in the series. He and Meryl assist Snake in Outer Haven by allowing him time to reach the server room. It is revealed that he had been in love with Meryl since he first saw her at Shadow Moses, and they get married in the epilogue. Unlike all of the other soldiers in the Army and the PMCs, Johnny does not have nanomachines since he always avoided the injections due to his trypanophobia; the lack of these explains his frequent spells of colds and diarrhea. While this gives him poor combat performance in comparison to his squad mates, he is completely immune to Liquid Ocelot's ability to directly attack soldiers' nanomachines. He also appears in the first Metal Gear Online expansion as a playable character.Johnny Sasaki is voiced by Naoki Imamura in the Japanese version and by Dean Scofield in the English translation. Akiba is voiced by Jun Fukuyama in Japanese and by Beng Spies in English.
Introduced in Metal Gear Solid:
Donald Anderson Donald Anderson (ドナルド・アンダーソン, Donarudo Andāson) is a chief advisor associated with DARPA. In his younger years, the character appears as Sigint (シギント, Shiginto), a technical advisor of FOX that provides Zero's technical support for Naked Snake in Metal Gear Solid 3: Snake Eater and can later be recruited into the early FOXHOUND in Portable Ops. In his later years, the DARPA chief abuses his position while conspiring with Kenneth Baker and Jim Houseman, but he was tortured for information by the rogue FOXHOUND and is killed by Revolver Ocelot, and impersonated by various individuals in the original Metal Gear Solid games. Anderson is implied in Peace Walker and Metal Gear Solid V to have contributed Cipher's technology which later oversees the AI proxies that would control governments and military. Donald Anderson is voiced by Keiji Fujiwara for the Japanese version and by James C. Mathis III for the English translation.
Introduced in Metal Gear Solid:
Cyborg Ninja The Cyborg Ninja (サイボーグ忍者, Saibōgu Ninja) is an alias utilized by individuals wearing an powered armor exoskeleton while armed with a high-frequency blade throughout the Metal Gear Solid games: Gray Fox, Olga Gurlukovich and Raiden. In the Japanese version, the Cyborg Ninja was voiced by Kaneto Shiozawa (in Metal Gear Solid), Masaharu Sato (while impersonating Donald Anderson in Metal Gear Solid 2), and Takumi Yamazaki (in Metal Gear Solid: Digital Graphic Novel and Metal Gear Solid 2: Digital Graphic Novel). In the English translation, the Cyborg Ninja is voiced by Greg Eagles (in Metal Gear Solid), Vanessa Marshall (in Metal Gear Solid 2), Rob Paulsen (in Metal Gear Solid: The Twin Snakes), and Larc Spies (in Metal Gear Solid: Digital Graphic Novel and Metal Gear Solid 2: Digital Graphic Novel).
Introduced in Metal Gear Solid:
Sons of Big Boss The Sons of Big Boss are a splinter group of FOXHOUND seen in Metal Gear Solid led by Liquid Snake as the game's bosses.
Introduced in Metal Gear Solid:
Psycho Mantis Psycho Mantis (サイコ・マンティス, Saiko Mantisu) is a psychic expert for Liquid Snake's FOXHOUND unit in Metal Gear Solid. After the collapse of the Soviet Union, he came to America looking for a job. Prior to joining FOXHOUND, he worked with the KGB and the FBI. His special abilities include the psychic powers of psychokinesis and telepathy, which in a Fourth Wall-breaking scene allows him to identify certain games on the player's memory card and "move" the controller by making it vibrate. As a result of being disgusted with his father's inner thoughts, he burned his own village and started despising people. He also claims to be able to read the future, but this is implied to be a use of telepathy to find out what his opponents will do next as opposed to true clairvoyance. Mantis encounters Solid Snake twice, the first time he takes control of Meryl Silverburgh's mind, the second encounter he and Snake do battle, with Mantis being killed (due to him being unable to predict Snake's actions when the player uses the second controller port). His predictions also seem to be susceptible to change, stating that Snake has a large place in Meryl's heart, but cannot see if their futures lie together. In Metal Gear Solid 4, the original Mantis makes an appearance after Screaming Mantis's defeat, attempting to "read your mind" as before, but cannot due to the advanced systems. He then tries to manipulate the controller, which (depending on whether controller vibration is available) either fails and infuriates him or succeeds and makes him scream in delight before he vanishes into the air. Drebin later reveals that the Beauty and the Beast Corps had been under the control of Mantis all along.The character's first chronological appearance is in Metal Gear Solid V: The Phantom Pain, where he is known as Tretij Rebenok (トリーチェゴ・レビョンカ, Torīchego Rebyonka, Третий ребёнок "The Third Child") The character's origin story explains that he was identified by Soviet researchers and taken to a facility in Moscow where he was housed with the Man on Fire's innate overriding desire for revenge. The two broke out, with the boy and the Man on Fire pursuing Venom Snake throughout the story, working alongside the game's antagonist Skull Face. The boy is able to detect the subtle electromagnetic currents running between the brain's synapses, and is particularly sensitive to feelings of anger, hatred and the desire for revenge. These feelings manifest in the physical world as a representation of those emotions. But since he is still a child, he is overwhelmed by these emotions and becomes a slave to the will of whoever is expressing them. Over the story's course, he identifies these feelings as being strongest in White Mamba and their relationship becomes symbiotic, magnifying the boy's power even further and allowing White Mamba to take control of Metal Gear Sahelanthropus. Once Snake disables Sahelanthropus, the boy steals a sample of a weaponized parasite designed to target English language speakers and passes it on to White Mamba and the two disappear.
Introduced in Metal Gear Solid:
Psycho Mantis was polled as the 8th "Greatest Video Game Villain of All Time" by IGN and his boss battle being the 2nd Greatest Moment in Gaming. In the Japanese version, Psycho Mantis has been voiced by Kazuyuki Sogabe (in Metal Gear Solid), Hiroshi Yanaka (in Metal Gear Solid: Digital Graphic Novel) and Shōzō Iizuka (in Metal Gear Solid 4). Psycho Mantis is voiced by Doug Stone in the English translation.
Introduced in Metal Gear Solid:
Sniper Wolf Sniper Wolf (スナイパー・ウルフ, Sunaipā Urufu) is a member of FOXHOUND and an elite sniper capable of going without food and staying still for up to a week. She typically forms an emotional connection with her targets before killing them with her favoured weapon, the Heckler & Koch PSG1, and uses mercury-tipped hollow-point bullets to poison her victims. She is also addicted to the drug diazepam.Born in present-day Iraqi Kurdistan around 1983 during the Iran–Iraq War, she witnessed the death of her family and thousands of others from a chemical attack by Saddam Hussein's government troops against the rebellious Kurds when she was five years old. She was captured by Saddam's forces and taken as an orphan by the Iraqi Ministry of Interior, who brainwashed her and brought a famed Gurkha sniper to train her to be a child combatant for the government. Three years later, during the 1991 uprisings in Iraq, she fled to a Kurdish refugee camp. There, the legendary U.S. Army Special Forces veteran Big Boss noticed her extraordinary abilities and brought her with him to the United States, where she received counselling and deprogramming to remove her Iraqi brainwashing, leaving only her fighting abilities with her. Extremely grateful, she thought of Big Boss as a modern Saladin and followed him in whatever he did, until his mutiny and later death at the hands of FOXHOUND operative Solid Snake (as depicted in Metal Gear 2: Solid Snake). She was then found by Solid Snake's brother Liquid Snake, who convinced her to join a FOXHOUND splinter cell under his command.In the alternate year 2005, during the Shadow Moses Island incident (Metal Gear Solid), Sniper Wolf goes rogue along with the rest of Liquid Snake's group when they take hostages and blackmail the U.S. government with a hijacked walking tank armed with nuclear weapons, demanding the corpse of Big Boss to be handed over to them. She cares for the huskies that Liquid intended to kill, as she enjoys their company, and is impressed with the hostage scientist Hal "Otacon" Emmerich giving his scarce food supply to the dogs. When Solid Snake (further referred to as Snake) infiltrates the island, Sniper Wolf wounds Snake's companion Meryl Silverburgh to lure him into a trap, capturing him so he could be tortured by another FOXHOUND member, Revolver Ocelot. Eventually, Snake defeats her in sniper duel in a snowy field by shooting her in the lung. After hearing Sniper Wolf's story of her life, and at her request to be at last "set free", Snake kills her over objections by Otacon, who professes his love for her. Solid Snake also uses her handkerchief to avoid attacks by her wolves by masking his scent with hers. Sniper Wolf's ghost can be seen if the player uses the in-game photo camera on her body.Sniper Wolf was originally planned to make a voice-over cameo appearance in Metal Gear Solid 2: Sons of Liberty (2001), during a conversation between Otacon and Olga "Ninja" Gurlukovich, and appears in a short flashback sequence. Her spirit shows up as a wolf in Metal Gear Solid 4: Guns of the Patriots (2008), in which an unrelated character named Crying Wolf also appears to engage in a sniper duel against Solid Snake. Sniper Wolf's costume can also be developed for the character Quiet in Metal Gear Solid V: The Phantom Pain.A special Sniper Wolf character card appears in the non-canon spin-off game Metal Gear Acid 2 (2005). Some other developers have also given homage type nods to the character, such as with an item "MGS Sniper Wulf Mk. II" in EA Montreal's Army of Two (2008) and a weapon "MG-S1 Sniper Wolfe" in the PlayStation 3 version of Visceral Games' The Godfather II (2009).A 1/8 scale Sniper Wolf action figure was released by McFarlane Toys in 1998. Two 1/6 scale figures were also released only in Japan by Yamato (an action figure) and Studio Saru Bunshitsu (a garage kit). In 2012, Sniper Wolf was chosen by Konami as one of their 64 iconic characters to participate in the Konami E3 Battle event, where she lost against Metal Gear REX in the semi-final fourth round. A "bishoujo statue" designed by Shunya Yamashita based on Shinkawa's original picture was released by Kotobukiya in 2016.Sniper Wolf is voiced by Naoko Nakamura in the Japanese version and by Tasia Valenza in the English translation.
Introduced in Metal Gear Solid:
Vulcan Raven Vulcan Raven (バルカン・レイブン, Barukanreibun) is an Inuit member of FOXHOUND who wields a giant Vulcan cannon and has shamanic powers of intuition seen in Metal Gear Solid. He is able to discern Solid Snake's heritage and was present in Outer Heaven prior to his involvement at Liquid Snake's FOXHOUND unit. He does battle with Snake twice, the first battle with Raven in an M1 Abrams tank, the second in a freezer with Raven being killed but also leaves with a cryptic message of Snake's violent future before his body is completely devoured by ravens. Vulcan Raven is voiced by Yukitoshi Hori in the Japanese version and by Peter Lurie in the English translation.
Introduced in Metal Gear Solid:
Decoy Octopus Decoy Octopus (デコイ・オクトパス, Dekoi Okutopasu) is a member of FOXHOUND specializing in impersonation seen in Metal Gear Solid. He even injects the blood of those he impersonates into his own body for a more "perfect" disguise. Along with the rest of his unit, he went rogue during Liquid Snake's Shadow Moses island incident. While impersonating Donald Anderson, he lies to Solid Snake about having the DARPA chief's detonation code found out by Psycho Mantis and also informs Snake of the PAL override system before being killed by the FoxDie virus. Decoy Octopus is voiced by Masaharu Sato (while impersonating Donald Anderson) in the Japanese version. In the English translation, Decoy Octopus is voiced by Greg Eagles (as Donald Anderson in Metal Gear Solid) and by James C. Mathis III (as Donald Anderson in Metal Gear Solid: Digital Graphic Novel).
Introduced in Metal Gear Solid:
Liquid Snake Liquid Snake (リキッド・スネーク, Rikiddo Sunēku), real name Eli (イーライ, Īrai), is Solid Snake's twin brother, Big Boss's second clone, and the main antagonist of Metal Gear Solid. One of Liquid's motivations in Metal Gear Solid is his jealousy and hatred towards Snake and his desire to surpass his "genetic destiny" from Big Boss. The character's young iteration is one of the main antagonists of Metal Gear Solid V: The Phantom Pain under the nickname White Mamba (ホワイトマンバ, Howaito Manba). Liquid Snake is voiced by Banjō Ginga in the Japanese version and by Cam Clarke in the English translation. White Mamba is voiced by Yutaro Honjo in Japanese and by Piers Stubbs in English.
Introduced in Metal Gear Solid:
Nastasha Romanenko Nastasha Romanenko (ナスターシャ・ロマネンコ, Nasutāsha Romanenko, Насташа Романенко) is an agent of the U.S. Defense Intelligence Agency and an expert on nuclear topics. She was born in the Ukrainian SSR and was just ten years old when the Chernobyl disaster took place. In both Metal Gear Solid and its GameCube remake Metal Gear Solid: The Twin Snakes, she is Solid Snake's contact on matters related to nuclear weapons. After the game's events, her character writes an autobiography titled In the Darkness of Shadow Moses: The Unofficial Truth and then forms the anti-proliferation group "Philanthropy" with the profits she made. This fictional publication serves as a plot summary of Metal Gear Solid (and reveals previously undisclosed plot details about the game's events), and is included as a bonus feature in Metal Gear Solid 2. Nastasha Romanenko is voiced by Eiko Yamada in the Japanese version and by Renee Raudman in the English translation.
Introduced in Metal Gear Solid:
Kenneth Baker Kenneth Baker (ケネス・ベイカー, Kenesu Beikā) is the president of the arms industry company ArmsTech that takes part in Metal Gear REX's project with the DARPA chief Donald Anderson as part of the United States' black budget. In Metal Gear Solid, he is taken prisoner by FOXHOUND, and tortured by Revolver Ocelot then rescued by Solid Snake. After he gives away his detonation code to Ocelot, Snake is unable to rescue him before as he is killed by the FoxDie virus; he is the first person to realize what's really happening and nearly tells the truth about Snake's mission but dies before he can finish his sentence. Kenneth Baker is voiced by Yuzuru Fujimoto in the Japanese version. In the English translation, Kenneth Baker is voiced by Allan Lurie (in Metal Gear Solid) and by Peter Renaday (in Metal Gear Solid: Digital Graphic Novel).
Introduced in Metal Gear Solid:
Jim Houseman Jim Houseman (ジム・ハウスマン, Jimu Hausuman) is the United States Secretary of Defense who observes the situation on Shadow Moses Island during Metal Gear Solid aboard an AWACS command plane. He makes only one appearance at the game's end via CODEC where he orders the Shadow Moses base to be bombed, partially out of spite because of the DARPA chief. According to In the Darkness of Shadow Moses, he commits suicide following the events of the game but Nastasha Romanenko suggests he was murdered. Jim Houseman is voiced by Tomohisa Asō in the Japanese version and William Bassett in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Raiden Raiden (雷電), real name Jack (ジャック, Jakku), is a former child soldier during the Liberian Civil War. He is the main character of Metal Gear Solid 2: Sons of Liberty that substitutes Solid Snake as the player character in the game's main portion fighting against Solidus Snake's terrorists to save the hostages from Big Shell. Raiden reappears in Metal Gear Solid 4: Guns of the Patriots as a third version of Cyborg Ninja as support, and returns as the protagonist of Metal Gear Rising: Revengeance. Raiden is voiced by Kenyu Horiuchi in the Japanese version and by Quinton Flynn in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Rosemary Rosemary (ローズマリー, Rōzumarī), or simply Rose (ローズ, Rōzu) for short, is Raiden's girlfriend.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Introduced during the Plant chapter portion of Metal Gear Solid 2, she is employed by the army as a data analyst, and saves the player's progress over Codec. Rosemary also supports Raiden by providing information about the Big Shell facilities and the other characters Raiden encounters in the game. Raiden and Rose spend most of their conversations talking about their relationship, something based on Kojima's real life. By the end of the game, Rosemary reveals herself to be a spy for the Patriots. She is then taken off the mission and replaced by an A.I. duplicate of her who openly mocks Raiden. After the final battle, Raiden is reunited with the real Rose, pregnant with his child, in front of Federal Hall National Memorial.In Metal Gear Solid 4, Rosemary appears as a psychological counselor in a combat stress platoon, offering Old Snake tips on dealing with stress. Though she was engaged to Raiden, their relationship ended after Rosemary supposedly had a miscarriage. Rosemary later marries Roy Campbell. In reality, Rosemary did give birth to Raiden's child John and her marriage is a ploy to protect the boy from the Patriots by having Campbell pose as John's father. After she reveals the truth to Raiden, the couple reconciles.Rosemary does not appear in Metal Gear Rising: Revengence, but Raiden mentions that she along with their son are living in New Zealand.Rosemary is voiced by Kikuko Inoue in the Japanese version. In the English translation, Rosemary is voiced by Lara Cody (in Metal Gear Solid 2 and Metal Gear Solid 4) and by Kari Wahlgren (in Metal Gear Solid 2: Digital Graphic Novel).
Introduced in Metal Gear Solid 2: Sons of Liberty:
Olga Gurlukovich Olga Gurlukovich (オルガ・ゴルルコビッチ, Oruga Gorurukobitchi, Ольга Гурлукович) is a member of her father's mercenary unit during Metal Gear Solid 2. Her character was somewhat based on Meryl Silverburgh yet Kojima wanted to make her look like a professional rather than a rookie. She first appears in the Tanker chapter as a member of the Gurlukovich mercenary unit and is the sole boss character in this portion of the game. She takes over her father's unit after her father's death in the Tanker chapter, lending her team to Solidus Snake's Sons of Liberty terrorist faction. She is actually an unwilling agent for the Patriots who are holding her daughter hostage, and assists Raiden as Mr. X (a second version of Cyborg Ninja), simulating Gray Fox during Metal Gear Solid. By doing so, she betrays her comrades to ensure her child's safety, a realization that makes her feel guilty. She is shot and killed by Solidus. Olga Gurlukovich is voiced by Kyoko Terase in the Japanese version and by Vanessa Marshall in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Dead Cell Dead Cell is a black-ops unit introduced in Metal Gear Solid 2 as the game's bosses. Formed by Solidus Snake, Dead Cell's original purpose was to prepare military bases for surprise attacks by holding unannounced training sessions.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Vamp Vamp (ヴァンプ, Vanpu) is a member of Dead Cell from Romania. He is a knife-throwing specialist endowed with numerous vampire-like abilities and attributes, such as a taste for blood, superhuman strength, speed, agility, the ability to walk on vertical walls and run across water (although this was based on a character that was scrapped). His moniker has dual meanings, being a short form of the English word vampire as well as referring to his bisexual orientation. Vamp was originally designed as a woman, but when the character of Fortune was introduced, the design was changed to that of a man, although the long black hair was retained, with the finished model being based on dancer Joaquín Cortés. First appearing in Metal Gear Solid 2, he was part of Solidus Snake's "Sons of Liberty" terrorist group during the Plant chapter. Vamp confronts Raiden several times throughout the course of the game being seemingly killed, but still manages to survive. In Metal Gear Solid 4, Vamp appears as a member of Liquid Ocelot's private army and as Raiden's rival. His "immortality" is revealed to be caused by nanomachines in his body that heal all of his wounds at an extraordinarily fast rate (augmenting his natural healing abilities). After Naomi Hunter designs a syringe used to destabilize the functionality of nanomachines, a wounded Vamp uses it to end his suffering. Vamp was also added to the second expansion of Metal Gear Online as a playable character. In the Japanese version, Vamp has been voiced by Ryotaro Okiayu (in Metal Gear Solid 2 and Metal Gear Solid 4) and by Shinya Tsukamoto (in Metal Gear Solid 2: Digital Graphic Novel). Vamp is voiced by Phil LaMarr in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Fortune Fortune (フォーチュン, Fōchun), real name Helena Dolph Jackson (ヘレナ・ドルフ・ジャクソン, Herena Dorufu Jakuson), is the leading member of Dead Cell and a member of Solidus Snake's "Sons of Liberty" terrorist group seen in Metal Gear Solid 2. She is an African-American woman with blond hair, something requested by Shinkawa as he thought she would be appealing. Her weapon is a railgun. Her codename comes from her nearly-miraculous ability to have bullets pass by her without hitting her. Fortune confronts Raiden as the first boss character in the Plant chapter, though she cannot actually be defeated due to her powers. The fight ends when Vamp arrives and is seemingly killed by Raiden, which makes her temporarily lose her will to fight until Vamp revives. Her true motive is to seek revenge against Solid Snake whom she believes was responsible for her father's death. Near the end of the game, she learns it was actually Revolver Ocelot who killed her father, and Ocelot reveals that her immunity to bullets was simply the result of an electromagnetic force field surrounding her body, which he deactivates before shooting her. However, Fortune manages to psychically deflect Ocelot's attacks from Metal Gear RAY before dying, with Snake hinting that her power as "Lady Luck" was not completely fake. Fortune is voiced by Yumi Tōma in the Japanese version and by Maula Gale in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Fatman Fatman (ファットマン, Fattoman) is a member of Solidus Snake's Dead Cell unit seen in Metal Gear Solid 2 that specializes in explosives. He is a psychopathic, overweight bald man in an EOD suit who moves around on rollerblades and is armed with a Glock 18 in addition to his bombs. Shinkawa had trouble designing him as he had been requested to make him obese and goodlooking at the same time. He is the second boss character in the Plant chapter. One of Raiden's early objectives in the Plant chapter is to deactivate a series of C4 bombs planted within each of the struts surrounding the Shell 1 core. The explosives are revealed to be nothing more than dummy bombs serving to activate the real bomb in the basement of Strut A. A similar bomb planted in the basement of the Shell 2 Core detonates, killing Fatman's former mentor Peter Stillman in the process. As Raiden meets with him, Fatman reveals that he wishes to become the world's most famous bomber by surpassing Stillman. Fatman then challenges Raiden to a duel at the heliport atop Strut E, which results in his death. It's later revealed that Fatman was actually an agent of The Patriots and that Stillman's presence in the facility was arranged to motivate Fatman into participating. He is named after the bomb dropped on Nagasaki, Japan on August 9, 1945. Fatman was voiced by Kōzō Shioya in the Japanese version and by Barry Dennen in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Solidus Snake Solidus Snake (ソリダス・スネーク, Soridasu Sunēku), also known by the public identity of George Sears (ジョージ・シアーズ, Jōji Shiāzu), is the third (and perfect) clone of Big Boss. After being alluded as the President of the United States in Metal Gear Solid, he makes his first official appearance as the main antagonist in Metal Gear Solid 2: Sons of Liberty, with a design based on Yoji Shinkawa's thoughts regarding how his brother Solid Snake would look when older, as well as being the adoptive father of Raiden. During Sons of Liberty, Solidus turned against the Patriots and posed as Snake while instigating a terrorist takeover of the Big Shell with Revolver Ocelot and Olga Gurlukovich in order to form his own nation to leave his impact on the world. For combat, Solidus wears a powered suit outfitted with a pair of tentacle-like mechanisms known as "snake arms". For weapons, he wields an FN P90 sub-machinegun and a pair of katana blades nicknamed "the Democrat" (民主刀, Minshutou) and "the Republican" (共和刀, Kyouwatou). Solidus tries to kill Raiden to use his foster son's nanomachines to lead him to the Patriots. However, Raiden severely injures Solidus in their duel atop Federal Hall National Memorial, slicing into the spine of Solidus's powered exoskeleton with a high frequency blade, and Solidus falls off the building and seemingly dies from his injuries. In Metal Gear Solid 4, Solidus's brain-dead body is used for Big Boss's reconstruction and as a decoy which used by Liquid Ocelot to hack into the Patriots' AI.In 2012, GamesRadar featured both him and Liquid Snake in the second place on the list of most evil clones in gaming, commenting that "as evil clones go, the ones that threaten the world with thermonuclear war and eradication rank as some of the worst." Solidus Snake was voiced by Akio Ōtsuka in the Japanese version and by John Cygan in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Sergei Gurlukovich Colonel Sergei Gurlukovich (セルゲイ・ゴルルコビッチ, Serugei Gorurukobitchi, Сергей Гурлукович) is Olga Gurlukovich's father and Revolver Ocelot's former commanding officer. Gurlukovich was also the one who provided a Hind-D helicopter to Liquid Snake in Metal Gear Solid with a possible usage of Metal Gear REX. An officer in Russia's Spetsnaz and GRU, he leads his personal team of mercenaries to seize the Discovery during the Tanker chapter of Metal Gear Solid 2 for the purpose of hijacking Metal Gear RAY. In the course of the operation, Gurlukovich is betrayed and killed by Ocelot due to the Patriots wanting RAY for their cause. Sergei Gurlukovich is voiced by Osamu Saka in the Japanese version and by Earl Boen in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
Scott Dolph General Scott Dolph (スコット・ドルフ, Sukotto Dorufu) is the commandant of the Marine Corps and Fortune's father. In the Tanker chapter of Metal Gear Solid 2, he is in charge of transporting Metal Gear RAY to its testing site and gives a speech to his troops in the cargo holds, unaware that the ship is being hijacked. He is killed by Revolver Ocelot before hijacking RAY, and his death serves as the root of Fortune's sorrow. Scott Dolph is voiced by Daisuke Gori in the Japanese version. In the English translation, Scott Dolph is voiced by Kevin Michael Richardson (in Metal Gear Solid 2) and by Phil LaMarr (in Metal Gear Solid 2: Digital Graphic Novel).
Introduced in Metal Gear Solid 2: Sons of Liberty:
Peter Stillman Peter Stillman (ピーター・スティルマン, Pītā Sutiruman) is a former NYPD bomb disposal expert working for the Bund Patrol and the former mentor of Fatman, having taught him everything he knows about explosives. In Metal Gear Solid 2, he infiltrates the Big Shell facility with SEAL Team 10. After Fatman planted bombs within each of the struts in the entire Big Shell facility, Stillman provides Raiden and Iroquois Pliskin with the tools needed to track down and deactivate each of the explosives, while providing support to the player via the codec. He eventually learns that the explosives Fatman planted were decoys used to activate the real bombs set to destroy the foundation of Shell 1 and Shell 2. Stillman races to the basement of Strut H, only to be caught in Fatman's trap: the bomb being equipped with a proximity sensor, detonates, killing Stillman. His character was most likely named after a character in Paul Auster's New York Trilogy. Peter Stillman is voiced by Shōzō Iizuka in the Japanese version. In the English translation, Peter Stillman has been voiced by Greg Eagles (in Metal Gear Solid 2) and by James C. Mathis III (in Metal Gear Solid 2: Digital Graphic Novel).
Introduced in Metal Gear Solid 2: Sons of Liberty:
Richard Ames Colonel Richard Ames (リチャード・エイムズ, Richādo Eimuzu) is a Secret Service agent and an operative for the Patriots. He previously served the Defense Intelligence Agency where he met Nastasha Romanenko. He was married to Nastasha for a while, but the two ended up divorcing. He was taken hostage during the Big Shell incident. In Metal Gear Solid 2, he met Raiden and then threatened by Revolver Ocelot, and then suddenly dies from an apparent heart attack. It is later revealed that he died from his nanomachines turning off his pacemaker thanks to a virus imitating FOXDIE put in place by the Patriots. Richard Ames is voiced by Masaharu Satō in the Japanese version and by Peter Renaday in the English translation.
Introduced in Metal Gear Solid 2: Sons of Liberty:
James Johnson James Johnson (ジェームズ・ジョンソン, Jēmuzu Jonson) is the President of the United States during the events of Sons of Liberty. He is the primary hostage Raiden is sent to rescue in the Plant chapter. After a series of ordeals, Raiden finally meets the President in the Shell 2 Core. The President reveals that he was actually a willing accomplice in the terrorist act, his vital signs being the input codes to activate Arsenal Gear (the new version of Metal Gear housed in Big Shell), but was imprisoned after a conflict of interest with Solidus Snake as Johnson wanted power whereas his predecessor preferred rebelling altogether. After he reveals the truth about Arsenal Gear to Raiden, he learns that he was manipulated to revolt by the Patriots as part of the S3 Plan. He is then killed by Revolver Ocelot while arguing with Raiden to kill him to prevent the terrorists from launching a nuclear strike. James Johnson is voiced by Yuzuru Fujimoto in the Japanese version. In the English translation, James Johnson is voiced by Paul Lukather (in Metal Gear Solid 2) and by H. Richard Greene (in Metal Gear Solid 2: Digital Graphic Novel).
Introduced in Metal Gear Solid 2: Sons of Liberty:
Emma Emmerich Emma Emmerich Danziger (エマ・エメリッヒ・ダンジガー, Ema Emerihhi Danjigā), nicknamed E.E., is an AI programmer and the stepsister of Hal Emmerich. When Emma was a child, her mother Julie Danziger married Huey Emmerich. Emma and Hal became very close as children and often swam together. When Hal was an adolescent, he was seduced by Emma's mother. Upon learning this, Huey committed suicide by drowning in the family's swimming pool and accidentally dragged Emma into the water in the process. She survived, but not without injury. Emma expected Hal to save her, but Hal was not aware that this was happening. After this, Emma developed a fear of water and became estranged from her stepbrother, blaming Hal for leaving the family afterwards. During the Plant chapter of Metal Gear Solid 2: Sons of Liberty, she is in charge of developing the AI that controls Arsenal Gear. She is escorted to the Shell 1 Core computer room by Raiden to download a virus into AI GW so that it will not be used by the terrorists, but is ambushed by Vamp on the oil fence. Raiden snipes Vamp, but before falling into the sea, Vamp fatally stabs Emma in the stomach. She later dies in the computer room confessing how she wanted to be closer to her stepbrother. Emma Emmerich is voiced by Maria Yamamoto in the Japanese version and by Jennifer Hale in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Naked Snake Naked Snake (ネイキッド・スネーク, Neikiddo Sunēku), real name Jack (ジャック, Jakku), is the main protagonist of the Metal Gear Solid prequel series. The character was originally introduced as Big Boss (ビッグ・ボス, Biggu Bosu), the genetic father of Solid Snake, Liquid Snake and Solidus Snake. The character's past is explored in Metal Gear Solid 3: Snake Eater as a member of FOX special forces. After defeating his legendary war hero mentor, he establishes FOXHOUND in Metal Gear Solid: Portable Ops and Militaires Sans Frontières in Metal Gear Solid: Peace Walker, and serves as Venom Snake's mental template in Metal Gear Solid V: The Phantom Pain. Naked Snake / Big Boss is voiced by Akio Ōtsuka in the Japanese version. In the English translation, Naked Snake is voiced by David Hayter and Big Boss is voiced by Kiefer Sutherland. Big Boss's aged version in Metal Gear Solid 4: Guns of the Patriots has been voiced by Chikao Ōtsuka in Japanese and by Richard Doyle in English.
Introduced in Metal Gear Solid 3: Snake Eater:
Zero Zero (ゼロ), real name David Oh (デイビッド・オウ, Deibiddo Ō), also known as Major Zero and Major Tom, is the true main antagonist of the entire Metal Gear series. Introduced in Metal Gear Solid 3, he is a former member of the British Special Air Service who serves as commanding officer of the FOX unit that communicates with Naked Snake via radio. In Portable Ops, Zero is arrested by the Pentagon for the FOX unit's revolt but is exonerated afterwards. Peace Walker revealed Zero as leader of the Cipher organization that controls the United States. Metal Gear Solid 4 revealed Zero's fallout with Big Boss over the "Les Enfants Terribles" project eventually caused his control over the world via AIs that would be the Patriots, and personally appears as a centennial in a persistent vegetative state (due to Skull Face's parasite in Metal Gear Solid V) to which Big Boss cuts off his oxygen supply and places him in a chokehold to facilitate his death. Zero is voiced by Banjō Ginga in the Japanese version. In the English translation, Zero is voiced by Jim Piddock (in Metal Gear Solid 3) and by Time Winters (in Metal Gear Solid V).
Introduced in Metal Gear Solid 3: Snake Eater:
Sokolov Dr. Nikolai Stepanovich Sokolov (ニコライ・ステパノヴィッチ・ソコロフ, Nikorai Sutepanovitchi Sokorofu, Николай Степанович Соколов) is a rocket scientist seen in Metal Gear Solid 3. Despite being cowardly and timid, he was able to defect to the United States two years before the events of the game, but was sent back to the USSR as a secret addition to the negotiations for ending the Cuban Missile Crisis. He develops the Shagohod. In the midsts of Naked Snake's retrieval of Sokolov, Colonel Volgin captures him and forces him to complete the weapon, and later seemingly dies of torture off-screen for trying to escape. Despite his apparent death, Sokolov returns in Portable Ops as the informant Ghost (ゴースト, Gōsuto). After he survived and escaped to the US with the help of FOX's new commander Gene, he builds the first Metal Gear model, a quadrupedal model, but still assists Big Boss as a result of the danger RAXA can make. He can also be recruited into the early FOXHOUND team. Nikolai Sokolov is voiced by Naoki Tatsuta in the Japanese version and by Brian Cummings in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
The Boss The Boss (ザ・ボス, Za Bosu), also known as The Joy (ザ・ジョイ, Za Joi), is the mentor and mother figure to Naked Snake, the biological mother of Ocelot, and one of the main antagonists of Metal Gear Solid 3: Snake Eater. The Boss is voiced by Kikuko Inoue in the Japanese version and by Lori Alan in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Volgin Yevgeny Borisovitch Volgin (エヴゲニー・ボリソヴィッチ・ヴォルギン, Evugenī Borisovitchi Vorugin, Евгений Борисович Волгин), better known as "Thunderbolt" in the West, is a Stalinist GRU colonel and the main antagonist of Metal Gear Solid 3: Snake Eater. His body carries an electric charge of ten million volts (speculated by Soviet scientists to be the result of Electrokinesis) that he uses chiefly for fighting and torture. A sadistic brute of a man, Volgin delights in causing wanton destruction and inflicting pain on anyone who crosses his path. He is also revealed to have been one of the chief perpetrators behind the 1940 Katyn Forest Massacre.During the events of Snake Eater, Volgin conspires to use the Shagohod as part of a bid to seize control of the Soviet Union by deposing Nikita Khrushchev and installing Leonid Brezhnev in his place. In the story's climax, he pilots Shagohod and engages Naked Snake and EVA in a fight to the death. After being critically wounded, it begins raining and he is struck by a bolt of lightning which leaves him comatose and near death. Upon being retrieved and experimented on by Russian scientists, Volgin returns as the Man on Fire (燃える男, Moeru Otoko) in Metal Gear Solid V: The Phantom Pain, where he desires revenge for his defeat; this desire is so great that it is the only thing keeping him alive, and his appearance as a man-made up entirely of fire is the physical manifestation of his desire. His appearance enables him to convert the energy from firearms and explosive rounds into powerful attacks. However, he eventually dies in peace in a final confrontation, where it is implied that he deduced Venom Snake is not the target of his vendetta.
Introduced in Metal Gear Solid 3: Snake Eater:
Volgin is voiced by Kenji Utsumi in the Japanese version and by Neil Ross in the English version. The Man in Fire is voiced by Dave Fouquette in English.
Introduced in Metal Gear Solid 3: Snake Eater:
EVA Eva (エヴァ) first appears in Metal Gear Solid 3: Snake Eater, set in 1964, as a motorbike-riding supposed KGB female spy and a former NSA codebreaker who has defected to the Soviets along with ADAM. She uses her charm and good looks to win over the trust of Naked Snake and the Soviet enemies. EVA wants to kill Major Ocelot to avoid revealing her cover but is stopped by Snake. Later, EVA infiltrates Colonel Volgin's GRU base through the disguise Tatyana (タチアナ, Tachiana), Sokolov's supposed lover, and assists Snake; "Tatyana" is tortured by Volgin with electric shocks in order to coerce the uncooperative Sokolov into completing the Shagohod's development and Volgin decided to have her "entertain". Throughout their respective missions, EVA and Snake began to develop romantic feelings for one another, but Snake was initially hesitant. She helps Snake destroy the Shagohod, kill Volgin and reach the Philosophers' Legacy so that she can later steal the treasure, even seeming to fall in love with Snake. At one point, EVA was nearly killed by the Colonel until The Boss volunteered to execute her personally; The Boss was actually trying to get her out of harm's way in reality. After the mission is completed, EVA and Snake have a one-night stand, but she could not bring herself to carry out the order of assassinating Snake, as she promised The Boss she would not. Instead, she flees with what she believes to be the Philosophers' Legacy (which was actually half taken by Ocelot for the CIA) as well as with intelligence data that lead to the breakthrough in the Chinese nuclear weapons program. Snake discovers a tape EVA has left revealing all her secrets. The epilogue prior to the credits goes on to state that EVA disappeared in Hanoi, North Vietnam, during the Vietnam War in 1968.EVA reappears in Metal Gear Solid: Portable Ops as a recruitable character by completing a series of optional missions. In 1971, Big Boss and EVA reconciled after she was tracked down and rescued in Hanoi, and is invited to become a founding member of a shadow government along with Zero, Para-Medic (Dr. Clark), Sigint and Ocelot. At some point, she also discovered Ocelot's codename of ADAM, and the two reconciled. In 1972, EVA volunteered to serve as a surrogate mother in the Les Enfants Terribles project designed with Big Boss's "sons" to maintain an icon for their organization. She was originally implanted with eight clone fetuses, though six were intentionally aborted in order to encourage stronger growth in the remaining two, giving birth to Solid Snake and Liquid Snake. Despite Big Boss's disapproval and eventual defection in opposition to Zero's methods,EVA does not make a direct appearance in Metal Gear Solid: Peace Walker. She would remain in contact with Big Boss, passing on cassette tape recordings to the Militaires Sans Frontieres in 1974. In them, she detailed further information on The Boss's final mission, and the motivations behind her actions, having been entrusted to pass this on to Big Boss. These tapes were later supplied to Big Boss with no return address except with her name EVA, with Big Boss hesitantly explaining that she was an "old acquaintance".
Introduced in Metal Gear Solid 3: Snake Eater:
In Metal Gear Solid 4: Guns of the Patriots, which is set in 2014, she appears under the identity of Big Mama (ビッグ・ママ, Biggu Mama) (also called Matka Pluku, Czech for "Mother of the Regiment") as the leader of the Paradise Lost Army resistance movement against The Patriots. It is revealed that she was fired from her job as a spy after she failed a mission in the previous game. She assists Old Snake in Eastern Europe. During a chase, EVA crashes her motorcycle and is impaired, seriously injuring her. When Liquid throws Big Boss's body into a fire, she attempts to save it but is nearly burned to death. Snake saved her from Liquid Ocelot's gunshot but the left side of her son's face gets badly burnt in the process. Although EVA initially appeared as if she died from injuries, it is later revealed that she died after coming into contact with the mutated FOXDIE virus carried in Snake's body.In Metal Gear Solid V: The Phantom Pain, Zero tasked EVA to arrange Big Boss's confinement at a hospital in Cyprus after XOF's attack on Mother Base, revealing this to Ocelot.
Introduced in Metal Gear Solid 3: Snake Eater:
EVA and Olga Gurlukovich's outfits can be used as costumes in Rumble Roses XX. EVA also makes a cameo appearance in Super Smash Bros. Brawl as an obtainable sticker, usable exclusively by Solid Snake in The Subspace Emissary.
Introduced in Metal Gear Solid 3: Snake Eater:
EVA's character model was based by Hideo Kojima on a gravure idol he liked ("○○里", a possible reference to Chisato Morishita (森下 千里)), and her personality traits were inspired by Fujiko Mine from Lupin III. He also said: "On Eva's back are signs of torture. There are burn marks and cut marks, as well as some very old scars. The Colonel interrogated her with 'hentai play' (変態プレイ)." According to Kojima, EVA's character was disliked by the English voice actors for her personality.In the Japanese version, EVA is voiced by Misa Watanabe (in Metal Gear Solid 3: Snake Eater, Metal Gear Solid: Portable Ops and Metal Gear Solid: Peace Walker) and Mari Natsuki (in Metal Gear Solid 4: Guns of the Patriots). In the English translation, EVA is voiced by Suzetta Miñet (in Metal Gear Solid 3: Snake Eater and Metal Gear Solid: Peace Walker), Vanessa Marshall (in Metal Gear Solid: Portable Ops) and Lee Meriwether (in Metal Gear Solid 4: Guns of the Patriots).
Introduced in Metal Gear Solid 3: Snake Eater:
In 2007, Tom's Games included her among the 50 greatest female characters in video game history, proposing that she should be portrayed in a live-action adaptation by "Uma Thurman, because she's tall, blonde and built to kick ass." In 2011, 1UP.com instead proposed Gillian Jacobs, adding that "EVA proved herself as one of the games' smartest and craftiest characters, playing heroes and villains alike like oversized flesh fiddles." The scene between the "sexy" EVA, Snake, and Ocelot in MGS3 was ranked as fifth on the 2010 list of the most Metal Gear amazing cutscenes by Joystick Division. EVA was chosen as "the perfect one to top the list" of the "PlayStation 2 babes" by Chris Reiter of Gaming Target in 2005.
Introduced in Metal Gear Solid 3: Snake Eater:
Para-Medic Para-Medic (パラメディック, Paramedikku), also known as Dr. Clark (クラーク博士, Kurāku Hakase), is a FOX support team member that provides medical information. Although it is set before the modern use of the word "paramedic", her codename instead comes from a portmanteau of "parachute" and "medic". Para-Medic provides Naked Snake with information in Metal Gear Solid 3 (surgical information, general information on the local flora and fauna, and being an avid movie-watcher who enjoys discussing her favorite films (despite Snake's disinterest)), and can later be recruited into the early FOXHOUND team in Portable Ops. Later games revealed that Para-Medic was the head of Zero's "Les Enfants Terribles" project, and was the one responsible for Gray Fox's revival and was in-turn murdered by the Cyborg Ninja. Originally, many people believed that Dr. Clark was a man, which is later explained as due to being so secretive that nobody knows anything about her, including the fact that she was actually a woman. Para-Medic is voiced by Houko Kuwashima in the Japanese version and by Heather Halley in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Cobra Unit The Cobra Unit is The Boss's personal team of military specialists and the bosses of Metal Gear Solid 3. Each member is named after the emotion that they bring into battle.
Introduced in Metal Gear Solid 3: Snake Eater:
The Pain The Pain (ザ・ペイン, Za Pein) has the ability to control hornets at his will, through the buzzing of a queen hornet that he keeps in his backpack. Apart from his hornets, The Pain is also equipped with a Tommy gun and grenades, using his hornets in conjunction with these weapons. He also uses his hornets to shield himself and create the form of a body double to confuse and draw his opponents into the open. In Metal Gear Solid 3, he fought and was defeated by Naked Snake. The Pain is voiced by Hisao Egawa in the Japanese version and by Gregg Berger in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
The Fear The Fear (ザ・フィアー, Za Fiā) is a member of the Cobra unit known for his superhuman speed and agility, as well as his freakish, fearsome appearance. Capable of dislocating his joints at will, he is able to crawl, walk on water, flip, leap extremely quickly in the manner of a spider, and also climb and jump around in trees with ease. He uses two crossbows in battle, the Little Joe and the William Tell, coating his bolts in the venom of the Brazilian wandering spider, setting them on fire or even outfitting them with explosives. He uses a variety of wires and ropes to enhance his mobility. On top of his incredible agility, he also uses Stealth camouflage to make himself nearly invisible. At the beginning of the battle in Metal Gear Solid 3, he shoots Naked Snake in the leg with a poisoned crossbow bolt, but wants to kill Snake himself rather than let the venom do the job for him. The poison begins to make Snake hallucinate, giving The Fear a distinct advantage, though Snake still manages to defeat him. The Fear is voiced by Kazumi Tanaka in the Japanese version and by Michael Bell in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
The End The End (ジ・エンド, Za Endo) is a member of the Cobra unit with exceptional sniping skills, born in the early 1860s, and the only member of the unit without an emotion-based codename, though it is explained in the game that it signifies "true oblivion". The End is a venerable expert sniper, but is visibly vulnerable as a result of his age. However, he is capable of photosynthesizing sunlight to sustain his life and go for days without food or water, later explained in The Phantom Pain as the effect of a species of parasite that lives in his body. He has a pet parrot (an Alexandrine parakeet) who can alert him to Snake's presence. The End is the only member of the Cobras who will not kill the player under any circumstances; he only uses tranquilizing rounds and will throw Snake in a jailcell when he is defeated. The strategic sniper fight between Naked Snake and The End in Metal Gear Solid 3 was developed by Kojima who wanted to bring a completely new style of boss battle to the series. However, the fight can be avoided if Snake kills a defenseless The End shortly before, or if the player saves during the fight and waits a week (or sets the system clock a week ahead), in which case The End dies of old age. In Peace Walker, The End's voice can sometimes be heard over the Codec during ghost missions, and Snake comments numerous times during mission briefings asking Kaz Miller if he saw any parrots with the enemy snipers and scouts. The End is voiced by Osamu Saka in the Japanese version and by J. Grant Albrecht in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
The Fury The Fury (ザ・フューリー, Za Fyūrī) is a pyromaniac and former Soviet cosmonaut. He utilizes a flame-resistant Soviet space suit in conjunction with a jet pack and a powerful flamethrower, both of which are powered by liquid rocket fuel UDMH. His codename reflects the unmitigated fury he feels towards the world while he is fighting. In Metal Gear Solid 3, he fought and is defeated by Naked Snake. The Fury is voiced by Masato Hirano in the Japanese version and by Richard Doyle in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
The Sorrow The Sorrow (ザ・ソロー, Za Sorō) was a powerful spirit medium and a former member of the Cobra unit, who used his psychic powers to aid his fellow soldiers on the battlefield. After being romantically involved with The Boss, he was the father of her child. After the ideological rift created by the Cold War, loyalties changed with him and The Boss each taking their respective sides. The Boss kills him in 1962 for making a double agent out of a sleeper agent she sent to OKB-1 to gather data on the USSR's space program. He makes many hidden appearances in ghost form throughout the game's cut scenes. In Metal Gear Solid 3, after escaping from Groznyj Grad and suffering a near-death experience, Naked Snake encounters The Sorrow while being forced to wade through an endless river swarming with all of the enemies that Snake has killed up to that point. The Sorrow is voiced by Yukitoshi Hori in the Japanese version and by David Thomas in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Raikov Ivan Raidenovitch Raikov (イワン・ライデノヴィッチ・ライコフ, Iwan Raidenovitchi Raikofu, Иван Райденович Райков) is a high-ranking officer within Groznyj Grad. He is implied to be Colonel Volgin's secret lover, and consequently has colonel-class authority despite only having a rank of major. The character is a parody of Raiden. The player is also able to wear a mask to impersonate him as Kojima noted that there were fans who wanted to play as Raiden in Metal Gear Solid 3. Besides impersonating Raikov, Naked Snake also has to knock him out to take his uniform and go to Groznyj Grad with the player also being given the choice of killing him. According to Kojima, the reason why he left Raikov's fate up to the player was largely because of Raiden's controversial popularity, where he'd allow the player, depending on whether their views of Raiden were positive or negative, to spare or kill Raikov, respectively. Raikov appears as a secret character in Portable Ops as being exiled to Colombia by the Soviet military after the fallout of Operation Snake Eater runs him afoul of the Kremlin. Raikov is voiced by Ken'yû Horiuchi in the Japanese version and by Charlie Schlatter in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Aleksandr Granin Aleksandr Leonovitch Granin (アレクサンドル・レオノヴィッチ・グラーニン, Александр Леонович Гранин) is the director of OKB-812 (also known as the Granin Design Bureau). He is the man who originally came up with the concept of bipedal walking tanks (the blueprints for Metal Gear REX and Metal Gear D). He supplies Naked Snake with the key to the door near the warehouse, but dies under Volgin's torture. Aleksandr Granin is voiced by Takeshi Aono in the Japanese version and by Jim Ward in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
Johnny Johnny is a GRU soldier seen in Snake Eater. He is assigned to watch over Naked Snake's jail cell in Groznyj Grad after Snake is captured by Volgin. He wears the standard uniform all the GRU soldiers wear in the game, except his balaclava is adorned with a large letter "J" on its forehead. Due to having an estranged son with the same name in America and claiming that all the first-born sons in his family are given that name, he is implied to be the grandfather of Johnny Sasaki. Johnny is voiced by Naoki Imamura in the Japanese version and by Michael Gough in the English translation.
Introduced in Metal Gear Solid 3: Snake Eater:
CIA Director The Director of Central Intelligence is a minor character who appears at the end of Metal Gear Solid 3: Snake Eater. The DCI resembles John McCone (the actual DCI in 1964), but is written as an unnamed fictionalized counterpart. He was the one who planned out the Operation Snake Eater, and as a result Naked Snake refuses to shake his hand during the award ceremony after returning from the mission. He was also the one who employed Ocelot (aka ADAM) as a triple agent within the CIA, KGB and GRU. In the end of Metal Gear Solid: Portable Ops, Ocelot ends up betraying the DCI under orders from a new employer and kills him in order to obtain the location of the Philosopher's Legacy. In the Japanese version, the DCI is voiced by an uncredited actor (in Metal Gear Solid 3) and by Masaharu Sato (in Portable Ops). In the English translation, the DCI is voiced by Paul Collins (in Metal Gear Solid 3) and by Jesse Corti (in Portable Ops).
Introduced in Metal Gear Solid 3: Snake Eater:
DOD Official The DOD Official appears at the end of Metal Gear Solid 3: Snake Eater, where he briefly talks to the DCI during Big Boss's award ceremony. He bears the likeness of Robert McNamara (the actual Secretary of Defense in 1964), although the character was later rewritten to be the Army Chief of Staff in Metal Gear Solid: Peace Walker. He makes an unvoiced appearance in the end of Metal Gear Solid: Portable Ops, where he can be seen standing next to Major Zero during FOXHOUND's inauguration ceremony. In Peace Walker, the character, who is now the Chairman of the Joint Chiefs of Staff, gets in touch with Big Boss when Peace Walker launches false nuclear launch data. He is the only member at the DEFCON meeting who believes Big Boss when told that the nuclear launch data is false after the latter provides proof, but is held at gunpoint by the other executive members when he orders them to stand down from retaliating. Big Boss ultimately succeeds, however, in stopping the false data from being sent.
Introduced in Metal Gear Solid: Portable Ops:
Jonathan Jonathan (ジョナサン, Jonasan) is one of the Red Army soldiers stationed at the San Hieronymo base. He is the first of the enemy soldiers to be recruited by Naked Snake's early FOXHOUND group. After meeting Snake and Roy Campbell, Jonathan says the Red Army personnel were assigned to build the base as an alternate strategic missile site after the Cuban Missile Crisis; detente and the USSR's commitment to the SALT negotiations resulted in the abandonment of the base, triggering the soldiers' decision to join Gene. Jonathan is left impressed with Snake's idealism and also helps in treating Campbell's bout with malaria. As Gene manipulates the Soviet soldiers into killing each other later in the game, Jonathan takes a few rounds meant for Snake and dies in Snake's arms, leading Snake to scream out in sorrow and rage. Jonathan's death comes to traumatize Snake deeply, further shaping the ideals and principles that Snake comes to uphold as Big Boss. Jonathan is voiced by Takahiro Fujimoto in Japanese and by Robin Atkin Downes in English.
Introduced in Metal Gear Solid: Portable Ops:
Colonel Skowronski Skowronski is a commander of the Red Army base in San Hieronymo. A World War II veteran and former fighter pilot, Naked Snake finds him hiding aboard a ship in the harbor that housed his fighter plane collection. It is revealed that the colonel had been drinking after Gene's men took over the base and even turned the Red Army troops against him. Skowronski dies in an attempt to kill Gene using RAXA. When it shuts down, Ursula telekinetically picks him off the cockpit and drops him to his death. Colonel Skowronski is voiced by Tetsu Inada in Japanese and by Nick Jameson in English.
Introduced in Metal Gear Solid: Portable Ops:
Python Python (パイソン, Paison) is one of FOX's original members revealed to have worked alongside Naked Snake during the early stages of the US advisory effort in Vietnam. However, he was severely injured during a mission with the Civilian Irregular Defense Group that he lost the ability to regulate his body temperature. The US government operated on him to stabilize his body temperature, eventually putting him in a Sneaking Suit filled with liquid nitrogen and several needles on his head to vent the excess heat. The CIA uses him as a counterpart to Snake in case he rebelled. Python joins the player's pool if he is defeated by nonlethal means, but will burn to death if he is killed. Python is voiced by Yûsaku Yara in Japanese and by Dwight Schultz in English.
Introduced in Metal Gear Solid: Portable Ops:
Elisa and Ursula Elisa (エルザ, Eruza) and Ursula are split personalities of a teenage girl raised in East Germany to nuclear physicists who worked in the USSR. She is revealed to be a survivor of the 1957 Kyshtym disaster; the radioactive fallout triggered her psychic abilities. The girl went back to East Germany and underwent numerous ESP and psychic tests. The testing enabled the girl to create split personalities that people can mistake them as twins due to their different hair colors (Elisa has gold hair, where Ursula's hair is silver). Gene rescued her during a mission in 1966 and later trained her personas – Elisa in medicine and Ursula in combat abilities. Over the course of the game, Elisa helps Naked Snake. However, the Ursula personality kicks in during Snake's showdown with Metal Gear RAXA. The combined personalities attempt to stop Gene, 'she' is killed. Her last words to Snake cryptically point to important developments in later games. Elisa/Ursula is voiced by Saori Gotō in Japanese and by Tara Strong in English.
Introduced in Metal Gear Solid: Portable Ops:
Cunningham Lt. Cunningham is an African-American soldier and FOX's resident interrogation specialist that goes by the codename Boa. After losing his leg due to unspecified reasons and getting demoted to desk work by the CIA, the Department of Defense taps him to besmirch the CIA's reputation, a job he accepted due to desiring revenge for his demotion. This enables him to join Gene's revolt and later to interrogate Naked Snake about the Philosophers' Legacy. Snake defeats him upon learning of the DOD's plans, with his flying platform exploding shortly thereafter, although not before he attempts to destroy the base with a Davy Crockett round in an attempt to ensure Snake died with him. Cunningham is voiced by Daisuke Gori in Japanese and by Noah Nelson in English.
Introduced in Metal Gear Solid: Portable Ops:
Gene Gene is the commander of FOX and the main antagonist of Metal Gear Solid: Portable Ops. Having joined the unit under the codename Viper, he proves his worth by rescuing Sokolov and Elisa during missions to Eastern Europe. A doctor by trade with a moderate degree of political science knowledge, he gradually undermines Major Zero's authority and prepares his own rebellion. Gene participates in the Successor Project, a special program designed to create a military officer modeled after The Boss and highly educated in military strategy and tactics. The program results in Gene developing enhanced CQC abilities and powers of persuasion/mild telepathic powers. Naked Snake kills him after Gene reveals his plans behind the takeover of the San Hieronymo base. Recognizing Snake's combat skills, Gene bequeaths to Snake all the resources he had amassed for the military force Army's Heaven. Gene is voiced by Norio Wakamoto in Japanese and by Steven Blum in English.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Sunny Sunny Emmerich (サニー・エメリッヒ) is a gifted prodigy. She is Olga Gurlukovich's daughter, kidnapped at birth by the Patriots to manipulate her mother. Afterwards, Raiden rescues her from the Patriots, leaving her in Otacon's care. By the time of Metal Gear Solid 4, she is a gifted computer programmer where it is heavily implied that her status as prodigy is the result of genetic engineering experiments done to her at Area 51 while she was in the Patriots' possession. She along with Naomi Hunter design the FOXALIVE virus which Old Snake uses to disable the Patriots' AIs. Sunny returns in Metal Gear Rising: Revengeance, having been adopted by Otacon. She did attend school after becoming free of the Patriots' AIs, but was considered too "advanced"; after earning multiple degrees, she was hired by Solis Space & Aeronautics. She helps Raiden reach Pakistan to stop Armstrong's plans, later allowing Bladewolf and George to work with her at Solis. Sunny is voiced by Kikuko Inoue in the Japanese version and by Cristina Pucelli in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Drebin Drebin (ドレビン, Durebin) is a weapons launderer that's usually accompanied by his pet monkey Little Gray. In Metal Gear Solid 4, he assists Old Snake by disabling ID-tagged weapons taken from PMC troops. He also provides exposition on the origins of each of the Beauty and the Beast members. Drebin is actually a spy for the Patriots assigned to help Snake defeat Liquid Ocelot. He injects Snake with a syringe with nanomachines that allow Snake to use Drebin's weapons; in addition to secretly containing a new strain of FOXDIE programmed to kill EVA, Ocelot and Big Boss. His name is a reference to film character Frank Drebin in that he issues Snake "naked guns." Drebin is voiced by Keiji Fujiwara in the Japanese version and by Khary Payton in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Jonathan Jonathan (ジョナサン, Jonasan) is a hulking Korean-American who serves as the Rat Patrol team's heavy weapons specialist and has a mohawk in the shape of an exclamation mark. He is named in reference to the lead character of Policenauts. Jonathan is voiced by Hideyuki Tanaka in the Japanese version and by James Sie in the English translation.
Ed Ed (エド, Edo) is an African-American who serves as the Rat Patrol team's sniper and Meryl Sliverburgh's second-in-command. He is a tribute to the Policenauts character of the same name. Ed is voiced by Shōzō Iizuka in the Japanese version and by Dave Fennoy in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
The Beauty and the Beast Corps The Beauty and the Beast Corps (ビューティー＆ビースト部隊, Byūtī & Bīsuto Butai) are a team of female PMC operatives in mechanized suits seen Metal Gear Solid 4. Designed according to their animal designations, each member of the BB Corps featured the likeness of a different real-life supermodel. Their "beast" form is voiced by Shōzō Iizuka in the Japanese version and by Fred Tatasciore in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Laughing Octopus Laughing Octopus (ラフィング・オクトパス, Rafingu Okutopasu) wears a special cybernetic suit that can imitate the appearance of her surroundings or other people, allowing her to blend in before attacking with powerful mechanical tentacles. She was born and raised in a small Scandinavian hamlet known as the Devil's Village, where the residents habitually eat octopus. A nearby cult took offense to the village's diet and attacked, sparing few, including the young girl. On pain of death, they tortured her into killing her entire family while laughing. This has utterly numbed her to bloodshed and has spawned an obsession with laughter, particularly during battle. The character's likeness was provided by Lyndall Jarvis. Laughing Octopus is voiced by Haruna Aimoto in the Japanese version and by Paula Tiso in the English translation. Various impersonations are voiced by Hideyuki Tanaka and Hiromi Tsuru in Japanese and by Christopher Randolph and Jennifer Hale in English.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Raging Raven Raging Raven (レイジング・レイヴン, Reijingu Reivun) is capable of true flying capabilities that utilizes UCAVs and a grenade launcher to attack her enemies. Born in Aceh, Indonesia, she was taken as a prisoner of war as a child. After enduring months of torture and starvation, her captors abruptly abandoned the prison, leaving her and the other child prisoners to be eaten alive by ravens. She was the last living child; though instead of eating her, the ravens peck away her bonds. She finds her captors' base camp and kills all soldiers and civilians present. The character's likeness was provided by Yumi Kikuchi. Raging Raven is voiced by Yumi Kikuchi in the Japanese version and by Nika Futterman in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Crying Wolf Crying Wolf (クライング・ウルフ, Kuraingu Urufu) is the strongest member as she can attack with a railgun or sheer brute force. She is also endowed with a strong sense of smell, enough to identify and track her quarry by scent in a snowstorm. She was born in an unnamed country ripped by civil war. After her family was killed in an attack, she fled the village with her baby brother and became a refugee. When hiding from an enemy unit in a shack, her brother began to cry; she covered his mouth to silence him and accidentally killed him. Upon reaching a refugee camp, she was driven insane by her grief and by the cries of children. She experienced visions of a wolf killing the children of the camp; in reality, it was she who did so. The character's likeness was provided by Mieko Rye. Crying Wolf is voiced by Eriko Hirata in the Japanese version and by Debra Wilson in the English translation.
Introduced in Metal Gear Solid 4: Guns of the Patriots:
Screaming Mantis Screaming Mantis (スクリーミング・マンティス, Sukurīmingu Mantisu) is the group's leader. Able to float by using unknown abilities, she has the power to crush people at will and manipulate soldiers to do her bidding, including killing their former allies. She has two puppets shaped like previous Metal Gear Solid bosses Psycho Mantis and The Sorrow. It is revealed that the Psycho Mantis puppet is used to control and manipulate living people while The Sorrow puppet can be used to manipulate dead bodies. However, her powers are only applicable on people implanted with nanomachines and cannot affect people who can suppress nanomachine activity. It is also revealed that Psycho Mantis was controlling her mind as a result of her insanity. The character's likeness was provided by Scarlett Chorvat. Screaming Mantis is voiced by Mao Yuki in the Japanese version and by Andrea Zafra in the English translation.
Introduced in Metal Gear Solid: Peace Walker:
Kazuhira Miller Benedict Kazuhira Miller (ベネディクト・カズヒラ・ミラー, Benedikuto Kazuhira Mirā), also known as McDonnell Benedict Miller (マクドネル・ベネディクト・ミラー, Makudoneru Benedikuto Mirā, known simply as "McDonnell Miller" in Metal Gear 2) and commonly known by his nickname Kaz, is an ambitious mercenary. Properly introduced in the prequel Metal Gear Solid: Peace Walker, he serves as second-in-command in the Militaires Sans Frontières mercenary group within Mother Base. His backstory reveals his upbringing as the son of a US officer and a Japanese woman and also notes his brief service in the JSDF. Unlike Big Boss, Kaz is initially characterized as idealistic, believing in MSF's idea of a nation for soldiers free of political ideology. However, he's naïve in underestimating Cipher and assumed he can maintain a business relationship over Zero's organization. This would come into full effect with Miller in Metal Gear Solid V. Following MSF's destruction, Miller gets embittered, seeing the concept of a nation for soldiers appropriated by other groups and reduced to being mercenary bands before he's rescued by Venom Snake from Soviet forces, enabling him to help in the new Diamond Dogs mercenary group's expansion, wearing a large trenchcoat and beret while walking with a limp having lost his left leg and right arm. Miller is deeply distrusting of anyone affiliated with Cipher, accusing the likes of Huey and Quiet of betrayal and calling for the defectors' deaths. Miller takes little satisfaction with vengeance on Skull Face but nevertheless believes in Diamond Dogs' cause. However, his faith is shaken with the revelation that Snake is actually a body double prompts Miller to reject Big Boss, acting as Solid Snake's mentor in Metal Gear 2 and later murdered for Liquid Snake's identity theft in Metal Gear Solid. Kazuhira Miller is voiced by Tomokazu Sugita in the Japanese version and by Robin Atkin Downes in the English translation.
Introduced in Metal Gear Solid: Peace Walker:
Amanda Amanda Valenciano Libre (アマンダ・バレンシアノ・リブレ, Amanda Barenshiano Ribure) assumes command of the FSLN after her father (their leader) is killed. After many of her members were forced out of Nicaragua by government forces, the KGB comes to the Sandinistas' aid by having them operate a banana plantation that is actually a front for drug-trafficking operations to generate funds for their rebel activities. During Metal Gear Solid: Peace Walker, Amanda shows a romantic interest in Naked Snake when Snake frees the Sandinista survivors from the Peace Sentinels. Towards the end of the game, Amanda leads the Sandinistas into fighting the KGB. In the game, the player can use Amanda to motivate former guerrillas recruited into the MSF. In Ground Zeroes, Amanda is stated to be working on MSF's Cuban operations. Amanda Libre is voiced by Romi Park in Japanese and by Grey DeLisle in English.
Introduced in Metal Gear Solid: Peace Walker:
Chico Ricardo Valenciano Libre (リカルド・バレンシアノ・リブレ, Rikarudo Barenshiano Ribure), nicknamed Chico (チコ, Chiko), is Amanda's younger brother. During Peace Walker, he tries to prove himself to his sister and the FSLN rebels despite his age. An argument results in Chico wandering around the forest and his capture by the Peace Sentinels. He also talks to Naked Snake about sightings of the Peace Walker AI weapon (which he calls "El Basilisco"). Chico has an interest in cryptozoology, is the one who briefs Snake on Monster Hunter missions and is in love with Paz Andrade. In Ground Zeroes, Chico is imprisoned and tortured in the military camp Camp Omega after trying to rescue Paz. It is also implied by tapes that he was forced to have sexual intercourse with Paz. He is aboard Big Boss's helicopter when it crashes into the Caribbean Sea; The Phantom Pain states that he did not survive, although Chico was planned to appear as an adult as seen in concept art. Chico is voiced by Kikuko Inoue in Japanese and by Antony Del Rio in English.
Introduced in Metal Gear Solid: Peace Walker:
Huey Dr. Emmerich (エメリッヒ博士, Emerihhi Hakase), nicknamed Huey (ヒューイ, Hyūi), is a wheelchair-using scientist who was born paraplegic due to having an abnormal spine, the son of a Manhattan Project scientist, and the father of Hal Emmerich. Previous games alluded his character; Metal Gear Solid revealed he was born on the same day as the Hiroshima attack when Snake first meets Hal, Metal Gear Solid 2 revealed that he committed suicide by drowning after finding out that his son was having an affair with his second wife, and Metal Gear Solid 3 alluded to the character as Granin's friend in the United States. In Metal Gear Solid: Peace Walker, he and Strangelove are responsible for building the Peace Sentinels' AI weapons for Coldman and later MSF's own Metal Gear ZEKE for Naked Snake. In a personal letter he wrote to Strangelove, which he asks Snake to deliver, it is revealed that they worked together while in NASA and Huey expressed much interest in Strangelove. Huey remains with Big Boss and MSF during Metal Gear Solid V: Ground Zeroes, working to hide MSF's nuclear capabilities from the United Nations. He is present when MSF is attacked by the XOF forces, though Metal Gear Solid V: The Phantom Pain confirms that Emmerich managed to escape the chaos, eventually developing a cybernetic leg-harness to gain the ability to walk. Emmerich maintains that he was misled by Cipher and abducted to work on the new model Metal Gear Sahelanthropus in Afghanistan for Skull Face, where he is rescued and detained by Diamond Dogs. He resumes his work for Diamond Dogs, but he faces with constant interrogation and lingering doubts about his allegiances, ultimately coming to view Diamond Dogs as being no different to Coldman or Cipher. Emmerich is accused by Diamond Dogs of murdering Strangelove and facilitating the attack on MSF for Cipher in exchange for his own safety, and is later found guilty of triggering a deadly new mutation in the vocal cord parasites that results in Venom Snake being forced to execute his own men and prevent them from escaping into the world. As punishment, Snake chooses to exile Emmerich from Diamond Dogs and sends him away in a single small lifeboat. Emmerich is forced to dump his leg-harness into the water to prevent the lifeboat from sinking, leaving him wheelchair-bound once more. Huey is voiced by Hideyuki Tanaka in Japanese and by Christopher Randolph in English.
Introduced in Metal Gear Solid: Peace Walker:
Coldman Hot Coldman (ホット・コールドマン, Hotto Kōrudoman) is depicted as a former director of the CIA sent to manage the CIA's Latin America operations, and is one of the main antagonists in Peace Walker. Because of bitterness over the demotion, Coldman plans to use the Peace Sentinels and the Peace Walker Project to regain his status as a power player in Washington. The true reason behind his exile was because he planned Operation Snake Eater. Coldman believes nuclear deterrence is a flawed theory, claiming humans won't retaliate during a nuclear strike due to fear of destroying themselves. Coldman believes that with impartial artificial intelligence, Peace Walker would guarantee retaliatory nuclear strikes against any nuclear power, ensuring true deterrence and worldwide peace. Coldman ultimately dies of Zadornov's gunshots, after inputting Peace Walker's nuclear launch codes and leaking false data to NORAD of an impeding USSR nuclear strike against the US. Coldman is ultimately proven wrong as senior members of NORAD planned to retaliate against the USSR. Coldman is voiced by Mugihito in Japanese and by H. Richard Greene in English.
Introduced in Metal Gear Solid: Peace Walker:
Zadornov Vladimir Aleksandrovich Zadornov (ヴラジーミル・アレクサンドロヴィチ・ザドルノフ, Vurajīmiru Arekusandorovitchi Zadorunofu, Владимир Александрович Задорнов) is one of the main antagonists in Metal Gear Solid: Peace Walker. The character initially disguised himself as Ramon Galvez Mena (ラモン・ガルベス・メナ, Ramon Garubesu Mena), a professor at the University of Peace. He possesses a red bionic right hand with built-in lighter and also can be launched like a rocket. He and his student Paz Ortega Andrade visit the Militaires Sans Frontières' base in Colombia to recruit MSF's services. Galvez helps out the MSF as they slowly uncover the Peace Sentinels' true motives in Costa Rica. He later unmasked himself as a KGB intelligence operative when Coldman prepares the Peace Walker to attack the MSF's Mother Base from inside a US base in Nicaragua. Zadornov planned to use Peace Walker to launch a nuke at Cuba, blaming the attack on the US which would lead to communism spreading throughout Central America. The MSF and FSLN capture him and lock him up at Mother Base, but he breaks out on several occasions and forces Big Boss to recapture him. He is eventually killed by Big Boss in self-defense. Vladimir Zadornov is voiced by Hōchū Ōtsuka in Japanese and by Steven Blum in English.
Introduced in Metal Gear Solid: Peace Walker:
Strangelove Strangelove (ストレンジラブ, Sutorenjirabu) is a British AI expert hired to work in the Peace Walker project and the mother of Hal Emmerich. During her stint with NASA in the late 1950s, Strangelove met The Boss and became enamored. She later met Huey while working in the Mercury program. In Peace Walker, her experience with The Boss and subsequent work in ARPA inspires her to create Peace Walker's AI matrix with The Boss's personality years later, which initially puts her at odds with Naked Snake. However, Strangelove joins MSF in helping create Metal Gear ZEKE's AI matrix. Strangelove was not present in Ground Zeroes, having left MSF a week before the IAEA inspection notification arrived due to the AI department not coming up with anything. The Phantom Pain reveals that she retrieved the Mammal Pod from Peace Walker's sunken remains to use as a basis for the Patriots' AI system at Zero's request, and she eventually married Huey and had their son Hal. Despite this, Strangelove reveals that she never loved Huey, and only wanted someone to conceive a child that she would see as hers and The Boss's child. Even after her death – Strangelove couldn't let go of The Boss and always claimed to be forever in love with her idol. When Huey later attempted to use Hal as a test subject for Metal Gear Sahelanthropus, Strangelove intervened and the two began to argue. As a result, Strangelove was locked inside the Mammal Pod by Huey, who left her to suffocate. The Mammal Pod is later recovered and used as evidence against Huey during interrogation. Strangelove is voiced by Yumi Kikuchi in Japanese and by Vanessa Marshall in English.
Introduced in Metal Gear Solid: Peace Walker:
Cécile Cécile Cosima Caminades (セシール・コジマ・カミナンデス, Seshīru Kojima Kaminandesu) is a French ornithologist. In Peace Walker, she is caught while trying to record quetzal sounds near an Incan ruin where the Peace Walker Project's AI laboratory is located. Cécile also was influenced by the May 1968 events in France, similar to other Parisian women at the time. The way her name is pronounced is a play on the phrase Kojima, kami nan desu (小島、神なんです, "Kojima, he's definitely a god"). She is also named after and visually based on Cécile Caminades, an employee from the Paris branch of Konami Digital Entertainment. Cécile did not appear in Ground Zeroes, as she had been evacuated from MSF and returned to Paris, France in preparation for the then-upcoming IAEA inspection. Cécile Caminades is voiced by Yū Kobayashi in Japanese and Catherine Taber in English.
Introduced in Metal Gear Solid: Peace Walker:
Paz Paz Ortega Andrade (パス・オルテガ・アンドラーデ, Pasu Orutega Andorāde) is first introduced in Peace Walker as an innocent schoolgirl at the University of Peace. She is the apparent student of Ramon Galvez Mena (Vladimir Zadornov) as seen to recruit the Militaires Sans Frontières' services in Costa Rica to encounter Coldman's Peace Sentinel AI experiments. In the game's true ending, she is revealed to be an agent of Cipher named Pacifica Ocean. Paz hijacks Metal Gear ZEKE and tries to launch a nuclear warhead at the US East Coast with the intention of framing MSF as being an extremist cult under Cipher's orders. Big Boss defeats her and she is thrown into the water from the force of ZEKE's explosion, although Big Boss suspected that there was a possibility that she survived. Paz provides commentary about her deep-cover mission in a ten-part series of audio tapes called "Paz's Diary". In the tapes, Paz talks about life in Mother Base and her fears about a strong reprisal from Cipher if she blew her cover.
Introduced in Metal Gear Solid: Peace Walker:
In Ground Zeroes, Paz is found alive drifting in the Caribbean before being captured by Skull Face's XOF group and brought to Camp Omega. During her interrogation she undergoes extreme torture, and the surgical implanting of explosive devices in her abdomen and womb. After learning of her survival, Big Boss is sent to retrieve her and Chico from the camp, believing her to be instrumental in finding and stopping Cipher. But during the two's rescue, however, Big Boss and Chico discover the surgical scars from one of the bombs inside Paz's unconscious body which the medic is forced to remove. While attempting to escape XOF's assault on MSF, Paz awakens and reveals the second bomb's presence before throwing herself from the helicopter in an attempt to save the others from the subsequent explosion which kills her.
Introduced in Metal Gear Solid: Peace Walker:
In The Phantom Pain, Venom Snake finds Paz apparently alive and recovering as the second bomb was apparently removed as well, though Paz was not aware of this when she jumped from the helicopter, and the explosion was actually caused by an enemy rocket launcher. Paz fell into the ocean, but managed to survive and was later brought back to Diamond Dogs. However, the impact caused her to suffer amnesia due to dissociative identity disorder, forgetting everything about Cipher and believing herself to still be a student in 1974. But when she removes a bomb from her stomach in front of him, Snake realizes that this is just a hallucination brought on by guilt over not being able to save her, and finally comes to terms with her death.
Introduced in Metal Gear Solid: Peace Walker:
Paz Ortega Andrade / Pacifica Ocean is voiced by Nana Mizuki in Japanese and by Tara Strong in English.
Introduced in Metal Gear Rising: Revengeance:
Maverick Security Consulting, Inc.
A private military and security company, Maverick acts as Raiden's primary support team over the course of the game.
Introduced in Metal Gear Rising: Revengeance:
Boris Popov Boris Vyacheslavovich Popov (ボリス・ヴャチェスラヴォヴィチ・ポポフ, Borisu Vyachesuravovichi Popofu, Борис Вячеславович Попов) is the president of Maverick and a former Russian Army soldier. Between the Big Shell incident and Liquid Ocelot's uprising, he helped Raiden rescue Sunny from the Patriots at Area 51, having once been friends with Sergei Gurlukovich. He later founded Maverick after the fall of the Patriots, taking in former members of Big Mama's Paradise Lost army and recruiting Raiden to their ranks. Boris Popov is voiced by Takayuki Sugo in Japanese and by JB Blanc in English.
Introduced in Metal Gear Rising: Revengeance:
Kevin Washington Kevin Washington (ケビン・ワシントン, Kebin Washington) is a military strategist who briefs Raiden on his missions and provides additional combat intelligence. Prior to his tenure with Maverick, he worked in disarmament, demobilization and reintegration at a NGO with ties to the United Nations, but after meeting Boris and seeing how ineffective the UN was at maintaining DDR, he left and joined Maverick instead. Kevin Washington is voiced by Yuichi Nakamura in Japanese and by Phil LaMarr in English.
Introduced in Metal Gear Rising: Revengeance:
Courtney Collins Courtney Collins (コートニー・コリンズ, Kōtonī Korinzu) is Maverick's lead data analyst. She went to the same university as Kevin who would later recommend Maverick to her following her graduation. Courtney Collins is voiced by Miyuki Sawashiro in Japanese and by Kari Wahlgren in English.
Introduced in Metal Gear Rising: Revengeance:
Doktor Wilhelm Voigt (ヴィルヘルム・フォークト, Viruherumu Fōkuto), known as "Doktor" (ドクトル, Dokutoru) is a German cybernetics expert who helps construct Raiden's new cyborg body. He originally served as a walking-weapons researcher in East Germany, but was left jobless after the Berlin Wall fell. He was later hired by a prosthetics laboratory in Dortmund and rises to prominence thanks to his knowledge of robotics and engineering. He is brought on as an adviser to Maverick to provide information on cyborg soldiers, as well as to build Raiden a new body and train him in its use. Doktor is voiced by Mugihito in Japanese and by Jim Ward in English.
Introduced in Metal Gear Rising: Revengeance:
Desperado Enforcement LLC The game's main antagonists, Desperado is a self-proclaimed PMC that actually conducts nefarious schemes. Many of its operatives are bionically enhanced.
Introduced in Metal Gear Rising: Revengeance:
Jetstream Sam Samuel Rodrigues (サムエル・ホドリゲス, Samueru Hodorigesu) is a master of a Brazilian fighting technique called the "New Shadow School", which had some derivations from a similar Japanese fighting style. Born and raised in Brazil, he is of Brazilian-Japanese heritage. Trained in swordsmanship by his father, who was killed by a former pupil under orders from the local drug cartel, Sam inherits his Murasama sword and becomes a vigilante and mercenary before being forced into service to Desperado by Armstrong. Known by the callsigns "Jetstream" (named after the fast flowing, narrow, meandering air currents in Earth's atmosphere) and "Minuano" (named for cold southwesterly wind that blows in the southern Brazilian state of Rio Grande do Sul and in Uruguay), Rodrigues throws his lot with Desperado for most of the game. Raiden's rivalry with Sam is a major driving force of the plot. Sam is eventually killed by Raiden in a duel, but gifts Raiden his sword, which is eventually used in the final battle with Armstrong. An additional chapter released as downloadable content details the backstory of how Sam joined Desperado. Jetstream Sam is voiced by Hiroaki Hirata in Japanese and by Philip Anthony-Rodriguez in English.
Introduced in Metal Gear Rising: Revengeance:
Sundowner Sundowner (サンダウナー, Sandaunā) is Desperado's unofficial leader and part of the Winds of Destruction, a team of elite operatives. His name is derived from a wind condition that occurs in Southern California. Born into poverty in Alabama, he joined the military during his early adulthood. He participated in several conflicts before leaving the service to become a mercenary for various PMCs until the fall of SOP, at which point he became part of Desperado. He wears a series of explosive shields, and his main weapons are two high-frequency machetes that combine into a pincer known as "Bloodlust". He is killed by Raiden during his assault on World Marshall. Sundowner is voiced by Ken Nishida in Japanese and by Crispin Freeman in English.
Introduced in Metal Gear Rising: Revengeance:
Mistral Mistral (ミストラル, Misutoraru) is the second member of the Winds of Destruction trio, named after the dry northern winds that blow from the Alps to the Mediterranean. Born in Algeria to French and Algerian parents, she was orphaned as a child during the Algerian Civil War, finding and butchering those responsible years later. She briefly served in the French Foreign Legion before being recruited into Desperado by Armstrong. Her cybernetic body is capable of hosting multiple limbs taken off Dwarf Gekkos. Her main weapon is a long staff that also acts as a whip known as "L'Etranger". She is killed by Raiden during a mission in Abkhazia after being doused in liquid nitrogen. Mistral is voiced by Romi Park in Japanese and by Salli Saffioti in English.
Introduced in Metal Gear Rising: Revengeance:
Monsoon Monsoon (モンスーン, Monsūn) is the third member of the Winds of Destruction, named after the seasonal wind systems that occur in West Africa and Australasia, in addition to being born in Cambodia. His most prominent ability is to magnetically dislocate his entire body to attack from a distance. He can also use smoke grenades for sudden attacks, and carries a pair of dual sais known as "Dystopia". His personality is that of a nihilistic, misanthropic sociopath, which is strongly implied to be the result of his being a survivor and victim of the Khmer Rouge's reign of terror. He is killed by Raiden during his assault on World Marshall. Monsoon is voiced by Masashi Ebara in Japanese and by John Kassir in English.
Introduced in Metal Gear Rising: Revengeance:
Blade Wolf Blade Wolf (ブレードウルフ, Burēdourufu), also known as the IF Prototype LQ-84i, is an unmanned AI weapon in Desperado's arsenal. When Raiden defeats the machine, Maverick rebuilds it as an ally. Nearly being destroyed during the battle with Armstrong, he later goes to live with Sunny at SOLIS. An additional chapter released as downloadable content details part of Blade Wolf's history with Desperado prior to his first encounter with Raiden. Blade Wolf is voiced by Yoshimasa Hosoya in Japanese and by Michael Beattie in English.
Introduced in Metal Gear Rising: Revengeance:
Khamsin Khamsin (カムシン, Kamushin) is an unofficial fourth member of the Winds of Destruction (only appearing in the Bladewolf DLC package), named after a hot, dry, dusty south–north wind in North Africa and the Middle East. He was discharged from the Marines due to friction between him and his teammates, and is held in similarly low regard by Desperado. Khamsin's body from the waist down is replaced with connectors to his mech suit, which wields a chainsaw/battle-axe hybrid heavy enough to require built-in rocket boosters to swing. Bladewolf is tricked by Mistral into killing Khamsin, whom she believed to be becoming a problem. Khamsin is voiced by Rikiya Koyama in Japanese and by Benito Martinez in English.
Introduced in Metal Gear Rising: Revengeance:
Senator Armstrong Steven Armstrong (スティーヴン・アームストロング, Sutīvun Āmusutorongu) is a Colorado senator and the primary backer of both Desperado Enforcement LLC and World Marshal Inc. and the main antagonist of Metal Gear Rising: Revengeance. He seeks to be elected as president of the United States in order to rebuild the country from within, purging those too weak or impoverished to contribute to society. He uses nanomachines to enhance his strength and change his skin to metal, reducing the effectiveness of attacks. He attempts to use Metal Gear EXCELSUS to assassinate the US president in Pakistan, but the weapon is destroyed by Raiden, who ultimately kills him. In the Jetstream DLC, Armstrong is revealed to be the one who cut off Sam's arm. Steven Armstrong is voiced by Unsho Ishizuka in Japanese and by Alastair Duncan in English.
Introduced in Metal Gear Solid V: The Phantom Pain:
Venom Snake Punished "Venom" Snake (パニッシュド・ヴェノム・スネーク, Panisshudo Venomu Sunēku), also referred to as Ahab (エイハブ, Eihabu), is a central character in Metal Gear Solid V: Ground Zeroes and Metal Gear Solid V: The Phantom Pain. He was originally a faceless medic of MSF who took a blast meant for Big Boss and fell into a coma. Afterwards, he underwent facial reconstruction and was subconsciously brainwashed in order to serve as Big Boss's body double distinguished by his bionic left arm, numerous facial scars, and the shrapnel sticking out from his forehead's right side. Snake is the Diamond Dogs' leader with various allies while facing Skull Face's XOF unit and the White Mamba. The character is retroactively established to be Big Boss's phantom (ビッグ・ボスのファントム, Biggu Bosu no Fantomu) in the original Metal Gear game who was killed by Solid Snake. Venom Snake is voiced by Akio Ōtsuka in the Japanese version and Kiefer Sutherland in the English translation.
Introduced in Metal Gear Solid V: The Phantom Pain:
Skull Face Skull Face (スカルフェイス, Sukaru Feisu) is the central antagonist of Metal Gear Solid V: Ground Zeroes and Metal Gear Solid V: The Phantom Pain. The commander of the mysterious Special Forces XOF unit, he is distinguished by his heavily scarred face, hairless head, and his choice of tailored suits over combat fatigues. His identity and nationality are initially unknown, and he claims to have forgotten his native language, though he is able to speak Hungarian and is later revealed to have been born in Transylvania before reverting to Romanian control. These early years were instrumental in forming his identity or lack thereof; unable to establish a consistent identity, Skull Face came to resent cultural imperialism and ultimately Cipher's ideology. His injuries were sustained when a rapeseed oil factory his parents worked in was bombed on suspicion of manufacturing weapons, an incident he describes as an atrocity before admitting the suspicions were correct; he characterizes the incident as a case of the ends justifying the means. Following this, he was taken to the Soviet Union and subject to an early form of "parasite therapy" whereby parasitic organisms were introduced to his body to keep him alive, and was later infected with one of Code Talker's parasites that made it impossible for him to speak his mother tongue. He eventually became a spy and assassin apparently specializing in poisons, killing Joseph Stalin in revenge for the subjugation of Romania. Skull Face considers the fire bombing to have burned the humanity out of him, and tortures his captives to the brink of death in order to see when the hope is extinguished, believing that he can discover the source of his own hope and regain his humanity.
Introduced in Metal Gear Solid V: The Phantom Pain:
Initially, Skull Face became an agent of the XOF organization created by Zero to covertly help in mission providing Intel, providing support in missions but he grew resentful of the accumulated fame while a lowly information officer would not be remembered due to Cipher keeping him in the shadows. By Ground Zeroes, he is a senior operative working on behalf of Cipher; he expresses dissatisfaction with Zero's leadership, and seeks information that will lead him to Zero. As the commander of XOF, he authorizes and participates in the torture and imprisonment of Paz and Chico, and later leads an assault which results in Big Boss's Militaires Sans Frontières' partial destruction. By The Phantom Pain, Skull Face has fallen out of favor with Cipher and has been exiled to Africa where he revives a project designed to weaponize a parasite as a form of ethnic cleansing as the parasite targets and kills speakers of different languages. He uses this as a pretext to develop a strain of vocal cord parasite that targets English speakers, intending to unleash it against Cipher and start a new Cold War by giving easy-to-make nuclear weapons to minority groups. To do this, he activates the unfinished Metal Gear ST-84 "Sahelanthropus", piloted by Psycho Mantis. However, Skull Face gets betrayed, leaving him crushed under a broken girder while Venom Snake's Diamond Dogs defeats ST-84. Skull Face accepts this defeat, apparent by his quoting of David Bowie's "Space Oddity". Incapacitated, Skull Face begs to be killed but Snake and Kazuhira Miller only shoot him several times with his own gun—detaching Skull Face's right arm and left leg—before turning away and leaving him to bleed to death, however, Dr. Emmerich finishes Skull Face off with another gunshot. His remains are cremated when his body's parasites still exhibited life signs, ultimately ending him.
Introduced in Metal Gear Solid V: The Phantom Pain:
Skull Face is voiced by Takaya Hashi in Japanese and by James Horan in English.
Introduced in Metal Gear Solid V: The Phantom Pain:
Quiet Quiet (クワイエット, Kuwaietto) is a sniper who appears in Metal Gear Solid V: The Phantom Pain. She first appears in the prologue chapter as part of a team attempting to kill Big Boss when discovered by Cipher, but suffers severe third degree burns in the attempt and is only kept alive through parasite therapy that gives her the ability to photosynthesize light, breathe through her skin, cloak herself, and move with superhuman speed and strength. Later in the story, she is defeated by Venom Snake in open combat and is brought back to Mother Base where she eventually starts participating in missions with Snake. The relationship between the two develops from one of mild mistrust mixed with mutual respect to one that is not easily defined but has moments of vulnerability, playful friendship, even romantic tension and ultimately, sacrifice. She is infected with the English-language strain of vocal cord parasites as a means of assassinating Snake, demanding her silence as a means of preventing symptoms from showing. Although Diamond Dogs are able to cure the infection, Quiet refuses the treatment owing to a latent desire for revenge. However, following the mutation of the parasite, she realizes that her silence alone is not enough to prevent symptoms from spreading, and she allows herself to be captured by Soviet forces in Afghanistan. Snake rescues her, but in the process Snake is bitten by a snake and the two are lost in a sandstorm as Soviet forces hunt for them, prompting Quiet to speak English to direct a helicopter to their location, but in doing so awakens the parasite. She disappears after leaving a goodbye message to Snake and vanishes in the desert in Afghanistan to prevent the infection from spreading. Dutch model Stefanie Joosten provides Quiet's likeness, motion capture and voice.
Introduced in Metal Gear Solid V: The Phantom Pain:
Code Talker Code Talker (コードトーカー, Kōdo Tōkā) is a Navajo biologist who specializes in parasite research. Born in 1880, he has survived for over a century due to his research, in which he identified and injected himself with the same species of parasite that gave The End his powers and longevity. Code Talker was ordered by Skull Face to duplicate the vocal cord parasite for use in his plan under the threat of the extermination of his people. He was later rescued by the Diamond Dogs and brought back to Mother Base to aid in finding a way to prevent or cure the parasite. Code Talker is voiced by Osamu Saka in Japanese and by Jay Tavare in English.
Introduced in Metal Gear Solid V: The Phantom Pain:
Skulls The Parasite Unit (パラサイトユニット, Parasaito Yunitto), also known as the Skulls (スカルズ, Sukaruzu), are an elite force of super soldiers working for XOF. They move at high speeds and possess glowing aqua eyes due to being purposefully infected by a strain of Code Talker's parasites, granting them enhanced abilities at the cost of their minds; these abilities included camouflage, corrosive gas projection, shapeshifting, and a thick metallic armor. They are encountered by Venom Snake repeatedly during The Phantom Pain, notably during the rescue of Kazuhira Miller and during the extraction of Code Talker.
Introduced in Metal Gear Solid V: The Phantom Pain:
D.D.
D.D., short for Diamond Dog, is a trained wolf who assists Diamond Dogs in The Phantom Pain. Venom Snake finds the orphaned puppy on the field and brings him back to Diamond Dogs, where Ocelot trains him to support on missions. As an adult, D.D. wears an eye patch similar to Snake's.
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Outer Heaven Outer Heaven (アウターヘブン, Autā Hebun) is Big Boss's ideology throughout the Metal Gear titles.
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The original iteration is initially a fictional nation-state that serves as the original Metal Gear game's setting located 200 kilometers north of the fictional region of Garzburg, South Africa. A legendary mercenary financed the nation's establishment to attract disillusioned soldiers, with a massive fortress as its centerpiece. Its potential threat to world affairs is boosted with the deployment of the TX-55 Metal Gear, a bipedal tank capable of launching a nuclear strike from anywhere on the planet. In the game, FOXHOUND commander Big Boss ordered rookie agent Solid Snake to infiltrate the mercenary state and destroy Metal Gear. After Snake successfully defies expectations and destroys Metal Gear, the nation's apparent leader confronts Snake but is ultimately defeated with Outer Heaven destroyed as well.The concept continued in Metal Gear 2: Solid Snake with the fortified nation Zanzibar Land (ザンジバルランド, Zanjibaru Rando) in Central Asia. Zanzibar Land declared themselves a nuclear power thanks to Metal Gear D provided by Big Boss, but his former subordinate infiltrates Zanzibar, and defeats both Metal Gear and Big Boss.
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Subsequent concepts of the ideology continue in the first two Metal Gear Solid games where Liquid Snake's FOXHOUND takes over Shadow Moses Island in Metal Gear Solid to threaten the world with Metal Gear REX and Solidus Snake's plan in Metal Gear Solid 2 to detonate an electromagnetic pulse on New York to destroy the Patriots' AI systems; both plans are foiled by Solid Snake and his allies.
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Outer Heaven's origins are depicted in Metal Gear Solid: Portable Ops as Naked Snake's response to Gene's "Army Heaven"; the former is given data with resources/personnel after the latter's defeat.
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A new iteration appears in Metal Gear Solid 4: Guns of the Patriots as Liquid Ocelot's mother company that runs five PMCs (Praying Mantis, Pieuvre Armement, Raven Sword, Werewolf and Otselotovaya Khvatka) thanks to a weak spot within the Patriots' AI network. After Old Snake and Otacon use the FOXALIVE virus to destroy the Patriots, Ocelot believes Big Boss's dream is finally achieved.
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FOXHOUND High-Tech Special Forces Unit FOXHOUND (ハイテク特殊部隊フォックスハウンド, Haiteku Tokushu Butai Fokkusuhaundo), alternatively spelled "FOX-HOUND" or "FOX HOUND", is a US Army elite special forces unit that has appeared in numerous forms throughout the Metal Gear series. FOXHOUND was originally established in 1990 according to the Metal Gear 2 user's manual to cope with local revolutions, regional complications, and global terrorist activities; Metal Gear Solid 3 would later retcon the year FOXHOUND was established, stating in the ending timeline that FOXHOUND was established in 1971. This unit specializes in black ops, carrying out top-secret operations within "unauthorized" combat zones which are too politically sensitive to intervene in through conventional means. In the MSX2 versions of Metal Gear and Metal Gear 2, FOXHOUND members are often referred to as "FOX HOUNDERS", although this term fell into disuse in later versions.
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In the original Metal Gear game, FOXHOUND has Big Boss as the team's commanding officer while Solid Snake and Gray Fox serve as field operatives. However, Big Boss betrays the unit in the end of the game. In Metal Gear 2: Solid Snake, Roy Campbell went from the unit's executive officer to the new commanding officer while drill instructor Master Miller and military strategist George Kasler form part of Solid Snake's support crew in the game.
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The FOXHOUND unit turns rogue in Metal Gear Solid as the Sons of Big Boss (ビッグ・ボスの息子たち, Biggu Bosu no Musuko-tachi) under Liquid Snake's leadership (Revolver Ocelot, Psycho Mantis, Sniper Wolf, Vulcan Raven and Decoy Octopus) involved in a terrorist revolt on Shadow Moses Island in the hopes of threatening the rest of the world with Metal Gear REX as a second "Outer Heaven" but were defeated/killed by Solid Snake with help from Otacon, the Cyborg Ninja and Meryl Silverburgh. The unit was disbanded; however, Raiden believed himself to be in the service of a new version in Metal Gear Solid 2 under the command of a Colonel AI representation controlled by the Patriots, and Meryl Silverburgh wears FOXHOUND's shoulder sleeve insignia on her right side in Metal Gear Solid 4 while leader of Rat Patrol Team One (ラットパトロールチームワン, Ratto Patorōru Chīmu Wan) (Johnny, Ed and Akiba).
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Outside the Metal Gear series, FOXHOUND is mentioned in Snatcher as a military unit that JUNKER Chief Benson Cunningham previously served; and in Policenauts as Meryl's former unit (the character being the basis for Meryl Silverburgh in Metal Gear Solid, has a paint tattoo of the team's original logo).
The Patriots The Patriots (愛国者達, Aikokushatachi), also referred to as the La-li-lu-le-lo (らりるれろ, Rarirurero), are a secret cabal that controls the United States. The group is initially believed to be led by an inner circle of 12 people known as The Wisemen's Committee (賢人会議, Kenjin Kaigi).
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In Metal Gear Solid 2, the Patriots manipulate the story's events. During the Tanker incident, they begin a smear campaign against Solid Snake to frame Philanthropy for an oil tanker's destruction in New York. During the Big Shell incident, Solidus Snake leads the Sons of Liberty (自由の息子達, Jiyū no Musuko-tachi) (Revolver Ocelot, Olga Gurlukovich and the Dead Cell members) take over Arsenal Gear which houses the AI GW to censor the flow of digital information as a third "Outer Heaven" by using Metal Gear RAY on New York to trigger an electromagnetic pulse to permanently destroy the Patriots' AI systems, however, the Patriots manipulated agents to ensure demise by Solid Snake and Raiden. But Philanthropy acquires a disk containing the Wisemen's Committee identities and learns that all 12 members have been dead for "about a hundred years".
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Metal Gear Solid 4 revealed that the Patriots were created from Zero's paranoia in the form of four computer AIs: TJ, TR, AL and GW controlled by fifth proxy AI JD. The AIs originally were created to carry out Zero's own will due to his increasing age and his skepticism that human subordinates would be able to do so. But over time, the system evolved from simply maintaining economic and political systems into creating an entirely new world order based on war economies, something not even Zero himself envisioned. Fortunately, the Patriots' network is shut down when Naomi Hunter's and Sunny's FOXALIVE computer worm used GW as a conduit to access the others. The Patriots' demise is further ensured with Zero's death at Big Boss's hands.
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The Patriots' AI in Metal Gear Solid 2 were voiced by Takeshi Aono and Kikuko Inoue in the Japanese version and by Paul Eiding and Lara Cody in the English translation.
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Philanthropy Philanthropy (フィランソロピー, Firansoropī) is a U.N. recognized anti-Metal Gear organization in Metal Gear Solid 2. Its primary members consist of Solid Snake, Hal "Otacon" Emmerich and Mei Ling. A large amount of the startup funds for the organization were provided by Nastasha Romanenko. Philanthropy is an NGO (non-government organization), which means that while the U.N. recognizes its existence, it has no official government backing. As Philanthropy is a semi-clandestine organization, Otacon must sometimes obtain equipment and information through less-than-legal methods; Snake mentions that on more than one occasion, Otacon has hacked classified networks to 'appropriate' experimental technology. In addition, it was also involved in activities comparable to terrorism.
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The Philosophers The Philosophers (賢者達, Kenjatachi) was an inner circle of 12 people, known as The Wisemen's Committee (賢人会議, Kenjin Kaigi), which was formed at the end of World War I when the leaders of the United States, China, and Bolshevik Russia entered a secret pact with a stated purpose of pooling money to rebuild countries affected by the war. The group's amassed amount totaled 100 billion dollars to fund war efforts and research; this sum became known as the "Philosopher's Legacy". After the original members' deaths during the 1930s, their followers began fighting amongst themselves to inherit the fund left by the original members. In Metal Gear Solid 3, Volgin uses the Philosopher's Legacy to create the fortress Groznyj Grad (グロズニュ・グラード, Gurozunyu Gurādo, Грозный Град) within the Soviet branch with the Shagohod and The Boss as collateral. Naked Snake retrieves the Philosophers' Legacy after the defeats of Volgin and The Boss for the American branch; however, EVA manages to obtain the data for the Chinese branch. The game's ending timeline establishes that a reorganized American branch (later retconned to Cipher) gets formed after accumulating the missing fund; Metal Gear Solid: Portable Ops changes this by showing Ocelot killing the DCI to end the Philosophers and obtains documents containing the Philosophers' identities and the location of the organization's funds.
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FOX The FOX unit (FOX部隊, Fokkusu Butai, which stands for "Force Operation X") is introduced in Metal Gear Solid 3 as Zero's special forces unit with Naked Snake as its first agent with Para-Medic and Sigint for additional support. The FOX unit turns renegade in Portable Ops under Gene's ultimate goal of Army's Heaven (アーミーズヘブン, Āmīzu Hebun) that would in fact victimize soldiers in pursuit of Gene's goals. In response, Naked Snake and Roy Campbell form their own team of specialists which goes on to become the FOXHOUND unit. Big Boss wears the FOX unit's shoulder sleeve insignia on the right side of his uniform in Peace Walker and Ground Zeroes. A covert strike called XOF is seen in Metal Gear Solid V under Skull Face's leadership. Originally a support network for FOX, XOF secretly continued carrying out ultra-sensitive and illegal operations as a covert division of Cipher. XOF carry out extremely sensitive black operations before having gone rogue as shown when they remove all of identifying markings from both personnel and equipment. After carrying out a successful assault on the MSF's destruction, XOF are eventually destroyed by the Diamond Dogs led by Venom Snake in The Phantom Pain. FOX's insignia is a stylized yellow fox on a black background while XOF's insignia is a black fox on a yellow background.
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MSF Militaires Sans Frontieres (国境なき軍隊, Kokkyō Naki Guntai, translated as "Soldiers Without Borders") is Naked Snake's mercenary group in Metal Gear Solid: Peace Walker. Per The Boss's will, Snake conceptualized MSF as capable of providing combat support to any individual or country, regardless of other factors. Kaz Miller helps develop MSF into a private military contractor offering a wide range of services on their Mother Base (マザーベース, Mazā Bēsu) in the Caribbean Sea thanks to Vladimir Zadornov and Paz Ortega Andrade during Coldman's Peace Sentinel takeover within Costa Rica and later the MSF's own housing of Metal Gear ZEKE. Metal Gear Solid V: Ground Zeroes shows the MSF unit is all but gone when the mysterious XOF organization attacks; many of the MSF personnel on assignment at the time of the attack return right away. They are disheartened by Big Boss's apparent death and later move on to work in other mercenary outfits. Militaires Sans Frontieres is a play on words on the humanitarian-aid non-governmental organization Médecins Sans Frontières dedicated to assisting countries ravaged by war and epidemics that are in need of doctors and medical experts. The HD Edition version of Peace Walker displays an announcement before the title screen stating that the fictional mercenary group is not in any way linked to the real group. Despite this, the fictional group is never mentioned by name in Metal Gear Solid V and the unit's emblem was modified to omit it. The group is renamed "Out Of Order" in the Japanese language novelizations of Peace Walker and The Phantom Pain authored by Hitori Nojima, and appears in the subtitles for the Japanese version of The Phantom Pain but is never spoken by the actual characters. The MSF's logo is a skull stylized after Pangaea inside a yellow and black circle.
Groups and organizations:
Cipher Cipher (サイファー, Saifā) is an American covert intelligence agency that served as the Philosophers' reorganized American branch as well as the Patriots' precursor. The group is officially mentioned in Metal Gear Solid: Peace Walker and referenced throughout most of Metal Gear Solid V: Ground Zeroes and Metal Gear Solid V: The Phantom Pain. The organization is initially formed by Zero with Big Boss to fulfill The Boss's ideal of a unified world. Cipher eventually grew too powerful and greedy to control everything, as seen with Donald Anderson/Sigint and Dr. Clark/Para-Medic. A fallout occurred where Big Boss and Zero interpreted The Boss's will differently; Zero taking the concept to mean control of the entire world to ensure unification, whereas Big Boss believed that The Boss's will wanted a world where soldiers were not used as tools by the government with Revolver Ocelot and EVA as additional support. Cipher has Pacifica Ocean oppose and frame MSF via Metal Gear ZEKE against the East Coast while Kazuhira Miller is a neutral business partner, and later eventually ends up disorganized by Skull Face's ambitions.
Groups and organizations:
Diamond Dogs The Diamond Dogs (ダイアモンド・ドッグズ, Daiamondo Dogguzu) is a splinter organization made from MSF's surviving remnants under Venom Snake's command in Metal Gear Solid V: The Phantom Pain. Diamond Dogs is based out of a new Mother Base in the Seychelles (given out of gratitude for their assistance in fighting off a coup) with Kaz Miller and Revolver Ocelot both as second in command. The Diamond Dogs' logo consists of a profile shot of a Rhodesian Ridgeback dog sat upon a cut diamond, finished off with a yellow scroll featuring the words "Diamond Dogs."
Reception:
The characters from the Metal Gear series have been well received by gamers with Solid Snake and Raiden appearing in a Famitsu poll that listed the fifty best video game characters; while the former was at the top, the latter was 42nd. Solid Snake has also appeared in multiple lists of best characters in gaming history, while Raiden and Revolver Ocelot were found as characters who should have their own spin-off games. While the variety of characters have been noted, publications often found some out of place as a result of their abilities and confusing changes occurring within them. The characters have also been praised for their actions within fight scenes, resulting in appealing cutscenes. The bosses have been praised not only for the requirements for defeating them, but also for the importance they have within the story. Various feature articles by video game publication have made articles regarding who is the best boss character within the series, but results have varied. During 2004, The Boss was awarded "Best New Character" by GameSpot for her role in Metal Gear Solid 3: Snake Eater. In 2013, GamesRadar praised the character roles of Revolver Ocelot/Liquid Ocelot, Psycho Mantis, The Boss and Steven Armstrong, placing them in their list of 100 best villains in video games. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Short-term trading**
Short-term trading:
Short-term trading refers to those trading strategies in stock market or futures market in which the time duration between entry and exit is within a range of few days to few weeks.
There are two main schools of thought: swing trading and trend following. Day trading is an extremely short-term style of trading in which all positions entered during a trading day are exited the same day.
Short-term trading:
Short term trading can be risky and unpredictable due to the volatile nature of the stock market at times. Within the time frame of a day and a week many factors can have a major effect on a stock's price. Company news, reports, and consumer’s attitudes can all have a positive or negative effect on the stock going up or down. According to Zweig (2006), "In an article in a women's magazine many years ago we advised the readers to buy their stocks as they bought their groceries, not as they bought their perfume" (p. 8). This means doing the research to spot the best opportunities and leaving the emotion and outside appeal out of the decision to buy or sell. Simply watching the news or reading financial statements will not prepare one to have success in the short term. By the time news comes out the markets have already responded and most of the potential gains for investors are gone. Buying or selling a stock that does not have much volume can move it up or down. Small investors have little effect but large mutual funds and hedge funds can determine the minute-to-minute pricing of stocks through supply and demand (Cramer, 2005, p. 96).Watching whether a stock is trending up or down can be a sign as to sell or buy in the short run. This is called the moving average or the average price of a stock over a specific period of time. As a stock is trending upward throughout a day or two it could be an opportunity for gains and as a stock trends downward it could be a great opportunity to short the stock. Many analysts use chart patterns in an attempt to forecast the market. Formulas and market theories have been developed to conquer short term trading. According to Masteika and Rutkauskas (2012), when viewing a stock's chart pattern over a few days, the investor should buy shortly after the highest chart bar and then place a trailing stop order which lets profits run and cuts losses in response to market price changes (p. 917–918). Historically, on average the stock markets lowest weekday is Mondays which offers a potential sale on any given stock (Lynch, 2000). Along with that, since 1950 most of the stock market's gains have occurred from November to April. Investors can use these known trends and averages to their advantage when trading. Due to the risk of short-term trading, small investors are often advised to limit short term trading and lean more towards value investing or buying and holding a position for the long term. According to Israelov and Katz (2011, p. 34), "Our suggestion (for long term investors) is to use short-term information for trade modification." This strategy has the value investor reviewing his stocks balance sheets, market signals, and charts every couple months in order to buy more or sell. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Sony Xperia 8**
Sony Xperia 8:
The Sony Xperia 8 is an Android smartphone marketed and manufactured by Sony. Part of Sony's midrange Xperia series, it was unveiled on October 7, 2019 as a Japan-exclusive device.
Design:
The Xperia 8 resembles the Xperia 10, but has an aluminum frame and Gorilla Glass 6 on the front and back. The screen has asymmetrical bezels, with the top bezel housing the earpiece, front-facing camera, notification LED and various sensors. The power button/fingerprint sensor and volume buttons are located on the right side of the device, while the 3.5mm headphone jack is located on the top. Notably, the shutter release button has been omitted. The rear cameras are centered and located near the top of the phone, with the LED flash above. The bottom edge has the primary microphone and a downward-firing speaker next to the USB-C port. At 158 mm × 69 mm × 8.1 mm and 170g (5.99 oz), the device is marginally larger and heavier than the 10 while seeing a slight decrease in depth. An IP65/68 rating is present, and four colors are available: White, Black, Orange and Blue.
Specifications:
Hardware The device shares its chipset with the Xperia 10, a Qualcomm Snapdragon 630 SoC and the Adreno 508 GPU. It is available with 4 GB of RAM and 64 GB of eMMC storage. MicroSD card expansion is supported up to 512 GB with a single-SIM or hybrid dual-SIM setup. The display is also identical to the 10's, a 6-inch (152mm) 21:9 1080p (1080 × 2520) IPS LCD panel which results in a pixel density of 457 ppi. The Xperia 8's battery is 4% smaller than the 10's, with a 2760mAh cell. Power and data connections are provided through the USB-C port. A dual camera setup is present on the rear, with a 12 MP primary lens and an 8 MP secondary lens. The front-facing camera has an 8 MP sensor.
Specifications:
Software The Xperia 8 runs on Android 9.0 "Pie". | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Episteme**
Episteme:
In philosophy, episteme (Ancient Greek: ἐπιστήμη, romanized: epistēmē, lit. 'science, knowledge'; French: épistémè) is knowledge or understanding. The term epistemology (the branch of philosophy concerning knowledge) is derived from episteme.
History:
Plato Plato, following Xenophanes, contrasts episteme with doxa: common belief or opinion. The term episteme is also distinguished from techne: a craft or applied practice. In the Protagoras, Plato's Socrates notes that nous and episteme are prerequisites for prudence (phronesis).
History:
Aristotle Aristotle distinguished between five virtues of thought: technê, epistêmê, phronêsis, sophia, and nous, with techne translating as "craft" or "art" and episteme as "knowledge". A full account of epistêmê is given in Posterior Analytics, where Aristotle argues that knowledge of necessary, rather than contingent, truths regarding causation is foundational for episteme. To emphasize the necessity, he uses geometry. Notably, Aristotle uses the notion of cause (aitia) in a broader sense than contemporary thought. For example, understanding how geometrical axioms lead to a theorem about properties of triangles counts as understanding the cause of the proven property of the right triangle. As a result, episteme is a virtue of thought that deals with what cannot be otherwise, while techne and phronesis deal with what is contingent.
Contemporary interpretations:
Michel Foucault For Foucault, an épistémè is the guiding unconsciousness of subjectivity within a given epoch – subjective parameters which form an historical a priori.: xxii He uses the term épistémè (French pronunciation: [epistemɛ]) in his The Order of Things, in a specialized sense to mean the historical, non-temporal, a priori knowledge that grounds truth and discourses, thus representing the condition of their possibility within a particular epoch. In the book, Foucault describes épistémè:: 183 In any given culture and at any given moment, there is always only one épistémè that defines the conditions of possibility of all knowledge, whether expressed in a theory or silently invested in a practice.
Contemporary interpretations:
In subsequent writings, he makes it clear that several épistémè may co-exist and interact at the same time, being parts of various power-knowledge systems. Foucault attempts to demonstrate the constitutive limits of discourse, and in particular, the rules enabling their productivity; however, Foucault maintains that, though ideology may infiltrate and form science, it need not do so: it must be demonstrated how ideology actually forms the science in question; contradictions and lack of objectivity are not an indicator of ideology. Jean Piaget has compared Foucault's use of épistémè with Thomas Kuhn's notion of a paradigm. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Science, technology, engineering, and mathematics**
Science, technology, engineering, and mathematics:
Science, technology, engineering, and mathematics (STEM) is an umbrella term used to group together the distinct but related technical disciplines of science, technology, engineering, and mathematics. The term is typically used in the context of education policy or curriculum choices in schools. It has implications for workforce development, national security concerns (as a shortage of STEM-educated citizens can reduce effectiveness in this area) and immigration policy, with regard to admitting foreign students and tech workers.There is no universal agreement on which disciplines are included in STEM; in particular whether or not the science in STEM includes social sciences, such as psychology, sociology, economics, and political science. In the United States, these are typically included by organizations such as the National Science Foundation (NSF), the Department of Labor's O*Net online database for job seekers, and the Department of Homeland Security. In the United Kingdom, the social sciences are categorized separately and are instead grouped together with humanities and arts to form another counterpart acronym HASS (Humanities, Arts, and Social Sciences), rebranded in 2020 as SHAPE (Social Sciences, Humanities and the Arts for People and the Economy). Some sources also use HEAL (health, education, administration, and literacy) as the counterpart of STEM.
Terminology:
History Previously referred to as SMET by the NSF, in the early 1990s the acronym STEM was used by a variety of educators, including Charles E. Vela, the founder and director of the Center for the Advancement of Hispanics in Science and Engineering Education (CAHSEE). Moreover, the CAHSEE started a summer program for talented under-represented students in the Washington, D.C., area called the STEM Institute. Based on the program's recognized success and his expertise in STEM education, Charles Vela was asked to serve on numerous NSF and Congressional panels in science, mathematics and engineering education; it is through this manner that NSF was first introduced to the acronym STEM. One of the first NSF projects to use the acronym was STEMTEC, the Science, Technology, Engineering and Math Teacher Education Collaborative at the University of Massachusetts Amherst, which was founded in 1998.
Terminology:
In 2001, at the urging of Dr. Peter Faletra, the Director of Workforce Development for Teachers and Scientists at the Office of Science, the acronym was adopted by Rita Colwell and other science administrators in the National Science Foundation (NSF). The Office of Science was also an early adopter of the STEM acronym.
Other variations A-STEM (arts, science, technology, engineering, and mathematics); more focus and based on humanism and arts.
eSTEM (environmental STEM) GEMS (girls in engineering, math, and science); used for programs to encourage women to enter these fields.
Terminology:
MINT (mathematics, informatics, natural sciences, and technology) SHTEAM (science, humanities, technology, engineering, arts, and mathematics) SMET (science, mathematics, engineering, and technology); previous name STEAM (science, technology, engineering, arts, and mathematics)STEAM (science, technology, engineering, agriculture, and mathematics); add agriculture STEAM (science, technology, engineering, and applied mathematics); more focus on applied mathematics STEEM (science, technology, engineering, economics, and mathematics); adds economics as a field STEMIE (science, technology, engineering, mathematics, invention and entrepreneurship); adds Inventing and Entrepreneurship as means to apply STEM to real world problem solving and markets.
Terminology:
STEMM (science, technology, engineering, mathematics, and medicine) STM (scientific, technical, and mathematics or science, technology, and medicine) STREAM (science, technology, robotics, engineering, arts, and mathematics); adds robotics and arts as fields
Geographic distribution:
Australia The Australian Curriculum, Assessment and Reporting Authority 2015 report entitled, National STEM School Education Strategy, stated that "A renewed national focus on STEM in school education is critical to ensuring that all young Australians are equipped with the necessary STEM skills and knowledge that they must need to succeed." Its goals were to: "Ensure all students finish school with strong foundational knowledge in STEM and related skills" "Ensure that students are inspired to take on more challenging STEM subjects"Events and programs meant to help develop STEM in Australian schools include the Victorian Model Solar Vehicle Challenge, the Maths Challenge (Australian Mathematics Trust), Go Girl Go Global and the Australian Informatics Olympiad.
Geographic distribution:
Canada Canada ranks 12th out of 16 peer countries in the percentage of its graduates who studied in STEM programs, with 21.2%, a number higher than the United States, but lower than France, Germany, and Austria. The peer country with the greatest proportion of STEM graduates, Finland, has over 30% of its university graduates coming from science, mathematics, computer science, and engineering programs.SHAD is an annual Canadian summer enrichment program for high-achieving high school students in July. The program focuses on academic learning particularly in STEAM fields.Scouts Canada has taken similar measures to their American counterpart to promote STEM fields to youth. Their STEM program began in 2015.In 2011 Canadian entrepreneur and philanthropist Seymour Schulich established the Schulich Leader Scholarships, $100 million in $60,000 scholarships for students beginning their university education in a STEM program at 20 institutions across Canada. Each year 40 Canadian students would be selected to receive the award, two at each institution, with the goal of attracting gifted youth into the STEM fields. The program also supplies STEM scholarships to five participating universities in Israel.
Geographic distribution:
China To promote STEM in China, the Chinese government issued a guideline in 2016 on national innovation-driven development strategy, instructing that by 2020, China should become an innovative country; by 2030, it should be at the forefront of innovative countries; and by 2050, it should become a technology innovation power.In February 2017, the Ministry of Education in China announced they would officially add STEM education to the primary school curriculum, which is the first official government recognition of STEM education. And later, in May 2018, the launching ceremony and press conference for the 2029 Action Plan for China's STEM Education was held in Beijing, China. This plan aims to allow as many students to benefit from STEM education as possible and equip all students with scientific thinking and the ability to innovate. In response to encouraging policies by the government, schools in both public and private sectors around the country have begun to carry out STEM education programs.However, to effectively implement STEM curricula, full-time teachers specializing in STEM education and relevant content to be taught are needed. Currently, China lacks qualified STEM teachers, and a training system is yet to be established.Several Chinese cities have taken bold measures to add programming as a compulsory course for elementary and middle school students. This is the case of the city of Chongqing.
Geographic distribution:
Europe Several European projects have promoted STEM education and careers in Europe. For instance, Scientix is a European cooperation of STEM teachers, education scientists, and policymakers. The SciChallenge project used a social media contest and the student-generated content to increase motivation of pre- university students for STEM education and careers. The Erasmus programme project AutoSTEM used automata to introduce STEM subjects to very young children.
Geographic distribution:
Finland In Finland LUMA Center is the leading advocate for STEM-oriented education. In the native tongue luma stands for "luonnontieteellis-matemaattinen" (lit. adj. "scientific-mathematical"). The short is more or less a direct translation of STEM, with engineering fields included by association. However unlike STEM, the term is also a portmanteau from lu and ma.
France The name of STEM in France is industrial engineering sciences (sciences industrielles or sciences de l'ingénieur). The STEM organization in France is the association UPSTI.
Hong Kong STEM education has not been promoted among the local schools in Hong Kong until recent years. In November 2015, the Education Bureau of Hong Kong released a document titled Promotion of STEM Education, which proposes strategies and recommendations on promoting STEM education.
Geographic distribution:
India India is next only to China with STEM graduates per population of 1 to 52. The total fresh STEM graduates were 2.6 million in 2016. STEM graduates have been contributing to the Indian economy with well paid salaries locally and abroad since last two decades. The turnaround of Indian economy with comfortable foreign exchange reserves is mainly attributed to the skills of its STEM graduates. In India, women make up an impressive 43% of STEM graduates, the highest percentage worldwide. However, they hold only 14% of STEM-related jobs. Additionally, among the 280,000 scientists and engineers working in research and development institutes in the country, women represent a mere 14% Nigeria In Nigeria, the Association of Professional Women Engineers Of Nigeria (APWEN) has involved girls between the ages of 12 and 19 in science based courses in other for them to pursue science based courses in the higher institutions of learning. National Science Foundation (NSF) In Nigeria has made conscious efforts to encourage girls to innovate, invent and build it through the 'invent it, build it challenge' program sponsored by NNPC.
Geographic distribution:
Pakistan STEM subjects are taught in Pakistan as part of electives taken in the 9th and 10th grade, culminating in Matriculation exams. These electives are: pure sciences (Physics, Chemistry, Biology), mathematics (Physics, Chemistry, Maths) and computer science (Physics, Chemistry, Computer Science). STEM subjects are also offered as electives taken in the 11th and 12th grade, more commonly referred to as first and second year, culminating in Intermediate exams. These electives are: FSc pre-medical (Physics, Chemistry, Biology), FSc pre-engineering (Physics, Chemistry, Maths) and ICS (Physics/Statistics, Computer Science, Maths). These electives are intended to aid students in pursuing STEM-related careers in the future by preparing them for the study of these courses at university.
Geographic distribution:
A STEM education project has been approved by the government to establish STEM labs in public schools. The Ministry of Information Technology and Telecommunication has collaborated with Google to launch Pakistan's first grassroots level Coding Skills Development Program, based on Google's CS First Program, a global initiative aimed at developing coding skills in children. The aim of the program is to develop applied coding skills using gamification techniques for children between the ages of 9 and 14.
Geographic distribution:
The KPITBs Early Age Programming initiative, established in the province of Khyber Pakhtunkhwa, has been successfully introduced in 225 Elementary and Secondary Schools. There are many private organizations working in Pakistan to introduce STEM education in schools.
Geographic distribution:
Philippines In the Philippines, STEM is a two-year program and strand that is used for Senior High School (Grade 11 and 12), as signed by the Department of Education or DepEd. The STEM strand is under the Academic Track, which also include other strands like ABM, HUMSS, and GAS. The purpose of STEM strand is to educate students in the field of science, technology, engineering, and mathematics, in an interdisciplinary and applied approach, and to give students advance knowledge and application in the field. After completing the program, the students will earn a Diploma in Science, Technology, Engineering, and Mathematics. In some colleges and universities, they require students applying for STEM degrees (like medicine, engineering, computer studies, etc.) to be a graduate of STEM, if not, they will need to enter a bridging program.
Geographic distribution:
Qatar In Qatar, AL-Bairaq is an outreach program to high-school students with a curriculum that focuses on STEM, run by the Center for Advanced Materials (CAM) at Qatar University. Each year around 946 students, from about 40 high schools, participate in AL-Bairaq competitions. AL-Bairaq make use of project-based learning, encourages students to solve authentic problems, and inquires them to work with each other as a team to build real solutions. Research has so far shown positive results for the program.
Geographic distribution:
Singapore STEM is part of the Applied Learning Programme (ALP) that the Singapore Ministry of Education (MOE) has been promoting since 2013, and currently, all secondary schools have such a programme. It is expected that by 2023, all primary schools in Singapore will have an ALP. There are no tests or exams for ALPs. The emphasis is for students to learn through experimentation – they try, fail, try, learn from it and try again. The MOE actively supports schools with ALPs to further enhance and strengthen their capabilities and programmes that nurtures innovation and creativity.
Geographic distribution:
The Singapore Science Centre established a STEM unit in January 2014, dedicated to igniting students' passion for STEM. To further enrich students' learning experiences, their Industrial Partnership Programme (IPP) creates opportunities for students to get early exposure to the real-world STEM industries and careers. Curriculum specialists and STEM educators from the Science Centre will work hand-in-hand with teachers to co-develop STEM lessons, provide training to teachers and co-teach such lessons to provide students with an early exposure and develop their interest in STEM.
Geographic distribution:
Thailand In 2017, Thai Education Minister Teerakiat Jareonsettasin said after the 49th Southeast Asia Ministers of Education Organisation (SEAMEO) Council Conference in Jakarta that the meeting approved the establishment of two new SEAMEO regional centres in Thailand. One would be the STEM Education Centre, while the other would be a Sufficient Economy Learning Centre.
Geographic distribution:
Teerakiat said that the Thai government had already allocated Bt250 million over five years for the new STEM centre. The centre will be the regional institution responsible for STEM education promotion. It will not only set up policies to improve STEM education, but it will also be the centre for information and experience sharing among the member countries and education experts. According to him, "This is the first SEAMEO regional centre for STEM education, as the existing science education centre in Malaysia only focuses on the academic perspective. Our STEM education centre will also prioritise the implementation and adaptation of science and technology."The Institute for the Promotion of Teaching Science and Technology has initiated a STEM Education Network. Its goals are to promote integrated learning activities and improve student creativity and application of knowledge, and to establish a network of organisations and personnel for the promotion of STEM education in the country.
Geographic distribution:
Turkey Turkish STEM Education Task Force (or FeTeMM—Fen Bilimleri, Teknoloji, Mühendislik ve Matematik) is a coalition of academicians and teachers who show an effort to increase the quality of education in STEM fields rather than focussing on increasing the number of STEM graduates.
Geographic distribution:
United States In the United States, the acronym began to be used in education and immigration debates in initiatives to begin to address the perceived lack of qualified candidates for high-tech jobs. It also addresses concern that the subjects are often taught in isolation, instead of as an integrated curriculum. Maintaining a citizenry that is well versed in the STEM fields is a key portion of the public education agenda of the United States. The acronym has been widely used in the immigration debate regarding access to United States work visas for immigrants who are skilled in these fields. It has also become commonplace in education discussions as a reference to the shortage of skilled workers and inadequate education in these areas. The term tends not to refer to the non-professional and less visible sectors of the fields, such as electronics assembly line work.
Geographic distribution:
National Science Foundation Many organizations in the United States follow the guidelines of the National Science Foundation on what constitutes a STEM field. The NSF uses a broader definition of STEM subjects that includes subjects in the fields of chemistry, computer and information technology science, engineering, geosciences, life sciences, mathematical sciences, physics and astronomy, social sciences (anthropology, economics, psychology and sociology), and STEM education and learning research.
Geographic distribution:
The NSF is the only American federal agency whose mission includes support for all fields of fundamental science and engineering, except for medical sciences. Its disciplinary program areas include scholarships, grants, fellowships in fields such as biological sciences, computer and information science and engineering, education and human resources, engineering, environmental research and education, geosciences, international science and engineering, mathematical and physical sciences, social, behavioral and economic sciences, cyberinfrastructure, and polar programs.
Geographic distribution:
Immigration policy Although many organizations in the United States follow the guidelines of the National Science Foundation on what constitutes a STEM field, the United States Department of Homeland Security (DHS) has its own functional definition used for immigration policy. In 2012, DHS or ICE announced an expanded list of STEM designated-degree programs that qualify eligible graduates on student visas for an optional practical training (OPT) extension. Under the OPT program, international students who graduate from colleges and universities in the United States can stay in the country and receive up to twelve months of training through work experience. Students who graduate from a designated STEM degree program can stay for an additional seventeen months on an OPT STEM extension.As of 2023, the U.S. faces a shortage of high-skilled workers in STEM, and foreign talents must navigate difficult hurdles in order to immigrate. Meanwhile, some other countries, such as Australia, Canada, and the United Kingdom, have introduced programs to attract talents at the expense of the United States. In the case of China, the United States risks losing its edge over a strategic rival.
Geographic distribution:
STEM-eligible degrees in US immigration An exhaustive list of STEM disciplines does not exist because the definition varies by organization. The U.S. Immigration and Customs Enforcement lists disciplines including architecture, physics, actuarial science, chemistry, biology, mathematics, applied mathematics, statistics, computer science, computational science, psychology, biochemistry, robotics, computer engineering, electrical engineering, electronics, mechanical engineering, industrial engineering, information science, information technology, civil engineering, aerospace engineering, chemical engineering, astrophysics, astronomy, optics, nanotechnology, nuclear physics, mathematical biology, operations research, neurobiology, biomechanics, bioinformatics, acoustical engineering, geographic information systems, atmospheric sciences, educational/instructional technology, software engineering, educational research, and landscape architecture.
Geographic distribution:
Education By cultivating an interest in the natural and social sciences in preschool or immediately following school entry, the chances of STEM success in high school can be greatly improved.STEM supports broadening the study of engineering within each of the other subjects, and beginning engineering at younger grades, even elementary school. It also brings STEM education to all students rather than only the gifted programs. In his 2012 budget, President Barack Obama renamed and broadened the "Mathematics and Science Partnership (MSP)" to award block grants to states for improving teacher education in those subjects.
Geographic distribution:
In the 2015 run of the international assessment test the Program for International Student Assessment (PISA), American students came out 35th in mathematics, 24th in reading and 25th in science, out of 109 countries. The United States also ranked 29th in the percentage of 24-year-olds with science or mathematics degrees.STEM education often uses new technologies such as RepRap 3D printers to encourage interest in STEM fields. STEM education can also leverage the combination of new technologies, such as photovoltaics and environmental sensors, with old technologies such as composting systems and irrigation within land lab environments. In 2006 the United States National Academies expressed their concern about the declining state of STEM education in the United States. Its Committee on Science, Engineering, and Public Policy developed a list of 10 actions. Their top three recommendations were to: Increase America's talent pool by improving K–12 science and mathematics education Strengthen the skills of teachers through additional training in science, mathematics and technology Enlarge the pipeline of students prepared to enter college and graduate with STEM degreesThe National Aeronautics and Space Administration also has implemented programs and curricula to advance STEM education in order to replenish the pool of scientists, engineers and mathematicians who will lead space exploration in the 21st century.Individual states, such as California, have run pilot after-school STEM programs to learn what the most promising practices are and how to implement them to increase the chance of student success. Another state to invest in STEM education is Florida, where Florida Polytechnic University, Florida's first public university for engineering and technology dedicated to science, technology, engineering and mathematics (STEM), was established. During school, STEM programs have been established for many districts throughout the U.S. Some states include New Jersey, Arizona, Virginia, North Carolina, Texas, and Ohio.Continuing STEM education has expanded to the post-secondary level through masters programs such as the University of Maryland's STEM Program as well as the University of Cincinnati.
Geographic distribution:
Racial gap in STEM fields In the United States, the National Science Foundation found that the average science score on the 2011 National Assessment of Educational Progress was lower for black and Hispanic students than white, Asian, and Pacific Islanders. In 2011, eleven percent of the U.S. workforce was black, while only six percent of STEM workers were black. Though STEM in the U.S. has typically been dominated by white males, there have been considerable efforts to create initiatives to make STEM a more racially and gender diverse field. Some evidence suggests that all students, including black and Hispanic students, have a better chance of earning a STEM degree if they attend a college or university at which their entering academic credentials are at least as high as the average student's.
Geographic distribution:
Gender gaps in STEM Although women make up 47% of the workforce in the U.S., they hold only 24% of STEM jobs. Research suggests that exposing girls to female inventors at a young age has the potential to reduce the gender gap in technical STEM fields by half. Campaigns from organizations like the National Inventors Hall of Fame aimed to achieve a 50/50 gender balance in their youth STEM programs by 2020.
Geographic distribution:
American Competitiveness Initiative In the State of the Union Address on January 31, 2006, President George W. Bush announced the American Competitiveness Initiative. Bush proposed the initiative to address shortfalls in federal government support of educational development and progress at all academic levels in the STEM fields. In detail, the initiative called for significant increases in federal funding for advanced R&D programs (including a doubling of federal funding support for advanced research in the physical sciences through DOE) and an increase in U.S. higher education graduates within STEM disciplines.
Geographic distribution:
The NASA Means Business competition, sponsored by the Texas Space Grant Consortium, furthers that goal. College students compete to develop promotional plans to encourage students in middle and high school to study STEM subjects and to inspire professors in STEM fields to involve their students in outreach activities that support STEM education.
The National Science Foundation has numerous programs in STEM education, including some for K–12 students such as the ITEST Program that supports The Global Challenge Award ITEST Program. STEM programs have been implemented in some Arizona schools. They implement higher cognitive skills for students and enable them to inquire and use techniques used by professionals in the STEM fields.
Geographic distribution:
Project Lead The Way (PLTW) is a provider of STEM education curricular programs to middle and high schools in the United States. Programs include a high school engineering curriculum called Pathway To Engineering, a high school biomedical sciences program, and a middle school engineering and technology program called Gateway To Technology. PLTW programs have been endorsed by President Barack Obama and United States Secretary of Education Arne Duncan as well as various state, national, and business leaders.
Geographic distribution:
STEM Education Coalition The Science, Technology, Engineering, and Mathematics (STEM) Education Coalition works to support STEM programs for teachers and students at the U. S. Department of Education, the National Science Foundation, and other agencies that offer STEM-related programs. Activity of the STEM Coalition seems to have slowed since September 2008.
Geographic distribution:
Scouting In 2012, the Boy Scouts of America began handing out awards, titled NOVA and SUPERNOVA, for completing specific requirements appropriate to scouts' program level in each of the four main STEM areas. The Girl Scouts of the USA has similarly incorporated STEM into their program through the introduction of merit badges such as "Naturalist" and "Digital Art".SAE is an international organization, solutions'provider specialized on supporting education, award and scholarship programs for STEM matters, from pre-K to the college degree. It also promotes scientific and technologic innovation.
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Department of Defense programs The eCybermission is a free, web-based science, mathematics and technology competition for students in grades six through nine sponsored by the U.S. Army. Each webinar is focused on a different step of the scientific method and is presented by an experienced eCybermission CyberGuide. CyberGuides are military and civilian volunteers with a strong background in STEM and STEM education, who are able to provide insight into science, technology, engineering, and mathematics to students and team advisers.
Geographic distribution:
STARBASE is an educational program, sponsored by the Office of the Assistant Secretary of Defense for Reserve Affairs. Students interact with military personnel to explore careers and make connections with the "real world". The program provides students with 20–25 hours of experience at National Guard, Navy, Marines, Air Force Reserve and Air Force bases across the nation.
SeaPerch is an underwater robotics program that trains teachers to teach their students how to build an underwater remotely operated vehicle (ROV) in an in-school or out-of-school setting. Students build the ROV from a kit composed of low-cost, easily accessible parts, following a curriculum that teaches basic engineering and science concepts with a marine engineering theme.
NASA NASAStem is a program of the U.S. space agency NASA to increase diversity within its ranks, including age, disability, and gender as well as race/ethnicity.
Geographic distribution:
Legislation The America COMPETES Act (P.L. 110–69) became law on August 9, 2007. It is intended to increase the nation's investment in science and engineering research and in STEM education from kindergarten to graduate school and postdoctoral education. The act authorizes funding increases for the National Science Foundation, National Institute of Standards and Technology laboratories, and the Department of Energy (DOE) Office of Science over FY2008–FY2010. Robert Gabrys, Director of Education at NASA's Goddard Space Flight Center, articulated success as increased student achievement, early expression of student interest in STEM subjects, and student preparedness to enter the workforce.
Geographic distribution:
Jobs In November 2012 the White House announcement before congressional vote on the STEM Jobs Act put President Obama in opposition to many of the Silicon Valley firms and executives who bankrolled his re-election campaign. The Department of Labor identified 14 sectors that are "projected to add substantial numbers of new jobs to the economy or affect the growth of other industries or are being transformed by technology and innovation requiring new sets of skills for workers." The identified sectors were as follows: advanced manufacturing, Automotive, construction, financial services, geospatial technology, homeland security, information technology, Transportation, Aerospace, Biotechnology, energy, healthcare, hospitality, and retail.
Geographic distribution:
The Department of Commerce notes STEM fields careers are some of the best-paying and have the greatest potential for job growth in the early 21st century. The report also notes that STEM workers play a key role in the sustained growth and stability of the U.S. economy, and training in STEM fields generally results in higher wages, whether or not they work in a STEM field.In 2015, there were around 9.0 million STEM jobs in the United States, representing 6.1% of American employment. STEM jobs were increasing around 9% percent per year. Brookings Institution found that the demand for competent technology graduates will surpass the number of capable applicants by at least one million individuals.
Geographic distribution:
According to Pew Research Center, a typical STEM worker earns two-thirds more than those employed in other fields.
Geographic distribution:
Trajectories of STEM graduates in STEM and non-STEM jobs According to the 2014 US census "74 percent of those who have a bachelor's degree in science, technology, engineering and math — commonly referred to as STEM — are not employed in STEM occupations." Updates In September 2017, a number of large American technology firms collectively pledged to donate $300 million for computer science education in the U.S.PEW findings revealed in 2018 that Americans identified several issues that hound STEM education which included unconcerned parents, disinterested students, obsolete curriculum materials, and too much focus on state parameters. 57 percent of survey respondents pointed out that one main problem of STEM is lack of students' concentration in learning.The recent National Assessment of Educational Progress (NAEP) report card made public technology as well as engineering literacy scores which determines whether students have the capability to apply technology and engineering proficiency to real-life scenarios. The report showed a gap of 28 points between low-income students and their high-income counterparts. The same report also indicated a 38-point difference between white and black students.The Smithsonian Science Education Center (SSEC) announced the release of a five-year strategic plan by the Committee on STEM Education of the National Science and Technology Council on December 4, 2018. The plan is entitled "Charting a Course for Success: America's Strategy for STEM Education." The objective is to propose a federal strategy anchored on a vision for the future so that all Americans are given permanent access to premium-quality education in Science, Technology, Engineering, and Mathematics. In the end, the United States can emerge as world leader in STEM mastery, employment, and innovation. The goals of this plan are building foundations for STEM literacy; enhancing diversity, equality, and inclusion in STEM; and preparing the STEM workforce for the future.The 2019 fiscal budget proposal of the White House supported the funding plan in President Donald Trump's Memorandum on STEM Education which allocated around $200 million (grant funding) on STEM education every year. This budget also supports STEM through a grant program worth $20 million for career as well as technical education programs.
Geographic distribution:
Events and programs to help develop STEM in US schools FIRST Tech Challenge VEX Robotics Competitions FIRST Robotics Competition Vietnam In Vietnam, beginning in 2012 many private education organizations have STEM education initiatives.
In 2015, the Ministry of Science and Technology and Liên minh STEM organized the first National STEM day, followed by many similar events across the country.
in 2015, Ministry of Education and Training included STEM as an area needed to be encouraged in national school year program.
Geographic distribution:
In May 2017, Prime Minister signed a Directive no. 16 stating: "Dramatically change the policies, contents, education and vocational training methods to create a human resource capable of receiving new production technology trends, with a focus on promoting training in science, technology, engineering and mathematics (STEM), foreign languages, information technology in general education; " and asking "Ministry of Education and Training (to): Promote the deployment of science, technology, engineering and mathematics (STEM) education in general education program; Pilot organize in some high schools from 2017 to 2018.
Women:
Women constitute 47% of the U.S. workforce, and perform 24% of STEM-related jobs. In the UK women perform 13% of STEM-related jobs (2014). In the U.S. women with STEM degrees are more likely to work in education or healthcare rather than STEM fields compared with their male counterparts.
Women:
The gender ratio depends on field of study. For example, in the European Union in 2012 women made up 47.3% of the total, 51% of the social sciences, business and law, 42% of the science, mathematics and computing, 28% of engineering, manufacturing and construction, and 59% of PhD graduates in Health and Welfare.In a study from 2019 it was shown that part of the success of women in STEM depends on the way women in STEM are viewed. In a study that researched grants given based primarily on project versus primarily based on the project lead there was almost no difference in the evaluation between projects from men or women when evaluated on project, but those evaluated mainly on the project leader showed that projects headed by women were given grants four percent less often.Improving the experiences of women in STEM is a major component of increasing the number of women in STEM. One part of this includes the need for role models and mentors who are women in STEM. Along with this, having good resources for information and networking opportunities can improve women's ability to flourish in STEM fields.
LGBTQ+:
People identifying within the group LGBTQ+ have faced discrimination in STEM fields throughout history. Few were openly queer in STEM; however, a couple of well-known people are Alan Turing, the father of computer science, and Sara Josephine Baker, American physician and public-health leader.Despite recent changes in attitudes towards LGBTQ+ people, discrimination still permeates throughout STEM fields. A recent study has shown that gay men are less likely to have completed a bachelor's degree in a STEM field and to work in a STEM occupation. Along with this, those of sexual minorities overall have been shown to be less likely to remain in STEM majors throughout college. Another study concluded that queer people are more likely to experience exclusion, harassment and other negative impacts while in a STEM career while also having fewer opportunities and resources available to them.Multiple programs and institutions are working towards increasing the inclusion and acceptance of LGBTQ+ people in STEM. In the US, the National Organization of Gay and Lesbian Scientists and Technical Professionals (NOGLSTP) has organized people to address homophobia since the 1980s and now promotes activism and support for queer scientists. Other programs, including 500 Queer Scientists and Pride in STEM, function as visibility campaigns for LGBTQ+ people in STEM worldwide.
Criticism:
The focus on increasing participation in STEM fields has attracted criticism. In the 2014 article "The Myth of the Science and Engineering Shortage" in The Atlantic, demographer Michael S. Teitelbaum criticized the efforts of the U.S. government to increase the number of STEM graduates, saying that, among studies on the subject, "No one has been able to find any evidence indicating current widespread labor market shortages or hiring difficulties in science and engineering occupations that require bachelor's degrees or higher", and that "Most studies report that real wages in many—but not all—science and engineering occupations have been flat or slow-growing, and unemployment as high or higher than in many comparably-skilled occupations." Teitelbaum also wrote that the then-current national fixation on increasing STEM participation paralleled previous U.S. government efforts since World War II to increase the number of scientists and engineers, all of which he stated ultimately ended up in "mass layoffs, hiring freezes, and funding cuts"; including one driven by the Space Race of the late 1950s and 1960s, which he wrote led to "a bust of serious magnitude in the 1970s."IEEE Spectrum contributing editor Robert N. Charette echoed these sentiments in the 2013 article "The STEM Crisis Is a Myth", also noting that there was a "mismatch between earning a STEM degree and having a STEM job" in the United States, with only around 1⁄4 of STEM graduates working in STEM fields, while less than half of workers in STEM fields have a STEM degree.Economics writer Ben Casselman, in a 2014 study of post-graduation earnings in the United States for FiveThirtyEight, wrote that, based on the data, science should not be grouped with the other three STEM categories, because, while the other three generally result in high-paying jobs, "many sciences, particularly the life sciences, pay below the overall median for recent college graduates." | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**GG45**
GG45:
GG45 (GigaGate 45) and ARJ45 (Augmented RJ45) are two related connectors for Category 7, Category 7A, and Category 8 telecommunication cabling. The GG45 interface and related implementations are developed and sold by Nexans S.A., while the ARJ45 interface and related implementations are developed and sold by Bel Fuse Inc. The electrical performance of each is compliant with IEC 61076-3-110, as published by the International Electrotechnical Commission. Furthermore, the ARJ45 connector meets the mechanical dimensions specified in IEC 61076-3-110.
Details:
The GG45 and ARJ45 connectors operate in the frequency band between 600 MHz and 5 GHz with shielded twisted pair and twinax cables. To reduce crosstalk, two of the four pairs have been moved so that each pair occupies one corner.
Details:
GG45 is a variant of ARJ45 that allows for cables terminated with male 8P8C (AKA RJ45) connectors to be plugged into GG45 female jacks. However, GG45 cables cannot plug into 8P8C jacks as a protrusion on the socket is designed to activate a switch on the jack for the alternative contact positions.Combined with an internal system of Faraday cages, the GG45 interface therefore has plenty of headroom, plus the ability to migrate to higher speed service by upgrading to Category 7A patch cords that activate the switch in the jack.There are two main variants of GG45/ARJ45: GG45 or ARJ45 HD is the full connector with 12 contacts, providing a Category 6 cable interface (100/250 MHz) for older devices as well as the new interface.
Details:
ARJ45 HS is the version without the Cat 6-compatible contacts, for a total of 8 contacts. 1 2 3 4 5 6 7 8 |‾‾█‾█‾█‾█‾█‾█‾█‾█‾‾| Pinout of GG45 and ARJ45 HD sockets. The protrusion ▒▒▒ | | activates a switch, redirecting the 3-6 and 4-5 pairs to |_█_█____▒▒▒____█_█_| the corners on a GG45 jack.
3'6' | | 4'5' |_| ARJ45 HS omits the Cat 6 compatible 3-6 and 4-5 pairs. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Announcer**
Announcer:
An announcer is a voice artist who relays information to the audience of a broadcast media programme or live event.
Television and other media:
Some announcers work in television production, radio or filmmaking, usually providing narrations, news updates, station identification, or an introduction of a product in television commercials or a guest on a talk show. Music television announcers were also called video jockeys (VJ).
Television and other media:
Announcers are often voice actors who read prepared scripts, but in some cases, they have to ad-lib commentary on the air when presenting news, sports, weather, time, and television commercials. Occasionally, announcers are also involved in writing the screenplay or scripts when one is required. Sometimes announcers also interview guests and moderate panels or discussions. Some provide commentary for the audience during sporting events known as sports announcers, parades, and other events.
Television and other media:
Announcers perform a variety of tasks including presenting news, sports, weather, traffic, and music. Other duties include interviewing guests, making public appearances at promotional events, announcing station programming information. Announcers are also sometimes responsible for operating studio equipment and producing/selling advertisements. Television and radio announcers generally have a bachelor’s degree in communications, broadcasting, or journalism. Some announcers cross "fields" by working in multiple media, such as television, radio, and commercials. For example, Bob Eubanks was in radio then became a television game show host, occasionally doing both jobs at the same time, and Townsend Coleman III started in radio then became a free-lance voice-over announcer and went on to voice cartoons.
Radio:
The role of the announcer in radio stations on air In some radio stations (mainly news), the announcers must have special skill, dexterity and agility when transmitting information.
Radio:
An example of this is the news station Radio Reloj, where the pages of two voices must have between 15 and 16 lines written, and those of one voice, between 13 and 15. If the information meets that requirement and the announcer from the beginning reads at an appropriate pace, must conclude at the exact minute. However, it may happen that some minutes the editors leave them a little long. Faced with this situation, the speaker accelerates the pace of his reading, in order to finish the text on time. Sometimes when the news is short, the announcer completes it with the so-called queues, which are important ephemeris, curious facts, congratulations to personalities. It may also be the case that information has the lines, in correspondence with its format, but has several points and followed. This implies that the announcer pauses, and has to speed up the reading rhythm to finish on the exact minute. In fact Mauricio Lomonte, an announcer for this station, said: It's hard work, because other than knowing the extent of this radio station, you have to talk for an entire hour, reading the news at first sight, without some preparation first, it takes a lot from the announcers, that's why it needs a lot of experience, focus and interpretation when being on air.
Radio:
Others Radio announcers are often known as disc jockeys (DJs). While some read from scripts, others completely ad-lib. These DJs’ tasks consist of on-air interviewing, taking/responding to listener requests, running contests, and making remarks about various subjects like the weather, traffic, sports, and other news. Most radio announcers announce the artists and titles of songs, but don't necessarily choose what song airs on the radio. Many stations have a management teams who select the songs ahead of time. Today radio stations have DJs update the station’s website with music, guest interviews, show schedules, and photos. Radio announcers are also known radio jockeys (RJ).
Live events:
Public address (PA) announcers work in physical locations, including sporting venues. They will give the attendees information about performing acts, speakers, players, score (such as a goal or touchdown), infractions, or the results of the event.
Live events:
Announcers may be specialized according to sport; for instance, a horse race announcer provides a rapid-fire second-by-second account of the race (as well as introducing the entries before the race), while a horse show announcer is the "voice of management" and helps keep the show moving, plays select music and makes announcements during the show. A baseball announcer may simply introduce the next batter or recap the previous half-inning. Public address announcers may be notable due to their longevity, or tenure with a popular team or venue. Some announcers, particularly in horse racing, may also be known for television or radio work. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Stereotomy (descriptive geometry)**
Stereotomy (descriptive geometry):
Stereotomy (Greek: στερεός (stereós) "solid" and τομή (tomē) "cut ") is the art and science of cutting three-dimensional solids into particular shapes. Typically this involves materials such as stone or wood which is cut to be assembled into complex structures (wall, vault, arch, etc.). In practice, the engineer makes a drawing of the intended stonework, showing where the joints in the face are to be located, and the stone cutter then details each block and cuts it to fit exactly with the others.In technical drawing stereotomy is sometimes referred to as descriptive geometry, and "is concerned with two-dimensional representations of three dimensional objects. Plane projections and perspective drawings of solid figures are used to describe and analyze their properties for engineering and manufacturing purposes. Attention is paid to the properties of surfaces, including normal lines and tangent planes." | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Pagoclone**
Pagoclone:
Pagoclone is an anxiolytic agent from the cyclopyrrolone family, related to better-known drugs such as the sleeping medication zopiclone. It was synthesized by a French team working for Rhone-Poulenc & Rorer S.A. Pagoclone belongs to the class of nonbenzodiazepines, which have similar effects to the older benzodiazepine group, but with quite different chemical structures. It was never commercialised.
Pagoclone:
It binds with roughly equivalent high affinity (0.7–9.1 nM) to the benzodiazepine binding site of human GABAA receptors containing either an α1, α2, α3 or α5 subunit. It is a partial agonist at α1-, α2- and α5-containing GABAA receptors and a full agonist at receptors containing an α3 subunit. In rats 5′-hydroxypagoclone was identified as a major metabolite. This metabolite has a considerably greater efficacy at the α1 subtype than the parent compound and was shown to have significant anxiolytic-like activity and to produce sedation. In contrast to zopiclone, pagoclone produces anxiolytic effects with little sedative or amnestic actions at low doses (0.3mg to 1.2mg per day).The pharmacologist David Nutt has suggested pagoclone as a possible base from which to make a better social drug, as it produces the positive effects of alcohol, such as relaxation and sociability, but without also causing the negative effects like aggression, amnesia, nausea, loss of coordination and liver damage. Its effect can be quickly reversed by the action of flumazenil, which is already used as an antidote to benzodiazepine overdose. Nutt has published studies praising the potential of pagoclone which were financed by Indevus which was seeking funding for a possible production of the compound. The long-term safety of pagoclone has not been assessed. The abuse potential of pagoclone has been assessed as being similar to, or slightly less than that of diazepam and it would also be expected to be somewhat safer due to its relatively weaker sedative effects, but development of pagoclone as a commercial drug would still be unlikely due to concerns about abuse.Pagoclone was trialed as a drug to improve a stammerer's speech fluency, but research for this application was discontinued following disappointing results in Phase II clinical trials.
Synthesis:
Pagoclone and pazinaclone both contain an isoindolone structural motif Reaction of 2-Amino-7-chloro-1,8-naphthyridine with phthalic anhydride leads to the corresponding phthalimide. Selective reduction of one of the imide carbonyl groups give the corresponding alcohol. Reaction with the carbanion from Ethyl 5-methyl-3-oxohexanoate leads to the product from the displacement of the hydroxyl group; 'this too may proceed via the acrylate obtained from aldol reaction of the ring opened imidal'. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**AI-10-49**
AI-10-49:
AI-10-49 is a small molecule inhibitor of leukemic oncoprotein CBFβ-SMHHC developed by the laboratory of John Bushweller (University of Virginia) with efficacy demonstrated by the laboratories of Lucio H. Castilla (University of Massachusetts Medical School) and Monica Guzman (Cornell University). AI-10-49 allosterically binds to CBFβ-SMMHC and disrupts protein-protein interaction between CBFβ-SMMHC and tumor suppressor RUNX1. This inhibitor is under development as an anti-leukemic drug.
Core binding factors:
Core-binding factor (CBF) is a heterodimeric transcription factor composed by the CBFβ and RUNX subunits (the latter is encoded by RUNX1, RUNX2, or RUNX3 genes). CBF plays critical roles in most hematopoietic lineages, regulating gene expression of a variety of genes associated with cell cycle, differentiation, signaling and adhesion. In hematopoiesis, CBF regulates progenitor cell fate decisions and differentiation at multiple levels. The function of CBF is essential for the emergence of embryonic hematopoietic stem cells (HSCs) and establishment of definitive hematopoiesis at midgestation. Similarly, in adult hematopoiesis, CBF regulates the frequency and differentiation of HSCs, lymphoid and myeloid progenitors, establishing CBF as a master regulator of hematopoietic homeostasis.
Core binding factors and leukemia:
CBF members are frequent targets of mutations and rearrangements in human leukemia. Point-mutations in RUNX1 gene have been reported in patients with familial platelet disorder, myeloid dysplastic syndrome, and chronic myelomonocytic leukemia. In addition, RUNX1 mutations have also been reported in Acute myeloid leukemia (AML). The RUNX1 and CBFB genes are targets of chromosome rearrangements that create oncogenic fusion genes in leukemia. The chromosome translocation t(12;21) (p13.1;q22) causes the fusion of the ETS variant 6 (ETV6) and RUNX1 genes results in ETV6-RUNX1 gene fusion and is the most common genetic aberration in childhood acute lymphoblastic leukemia (ALL). The "core binding factor AML" (CBF AML) [WHO classification] is the most common group of AML, including groups with the chromosome rearrangements inv(16)(p13q22) and t(8;21)(q22;q22). The chromosome translocation t(8;21)(q22;q22) creates the RUNX1-ETO fusion gene, which is expressed in FAB subtype M2 AML samples. The pericentric chromosome inversion inv(16)(p13q22) creates the CBFB-MYH11 fusion gene, which encodes the CBFβ-SMMHC fusion protein.
Inv(16) leukemia:
The inv(16) is present in all M4Eo subtype AML, representing one of the most common change in AML, and accounting for ≈12% of de novo human AML. Studies by various laboratories have established that CBFβ-SMMHC acts as a dominant repressor of CBF function in vivo and specifically blocks lymphoid and myeloid lineage differentiation.Treatment of AML varies based on the prognosis and mutations identified in the patient sample. Current treatment for inv(16) AML uses chemotherapy drugs, such as doxorubicin and cytarabine, with an estimated 5-year overall survival of 60% in young patients and only 20% in the elderly.
Discovery:
CBFβ-SMMHC outcompetes CBFβ for binding to RUNX1 by direct protein-protein interaction.Using a fluorescence resonance energy transfer (FRET) based assay, AI-4-57 was discovered as the lead compound which can inhibit CBFβ-SMHHC –RUNX1 protein-protein interaction. To get good in vivo pharmacokinetics, selectivity and potency AI-10-49 was developed which has a seven atom polyethylene glycol-based linker and a trifluoromethoxy substitution. This molecule releases RUNX1 from CBFβ-SMHHC specifically and restores the RUNX1 transcriptional program in inv(16) positive human leukemic cells. Viability assays showed AI-10-49 has an IC50 of 0.6μM. Pharmacokinetic studies showed that AI-10-49 has half-life of 380 minutes in mouse plasma. AI-10-49 prolonged the survival of mice transplanted with CBFβ-SMHHC leukemic cells without any signs of toxicity. AI-10-49 reduced viability and colony forming ability of human primary inv(16) leukemic blast cells, without affecting normal human bone marrow cells as wells non- inv(16) primary human leukemic blast cells. Overall, these findings validate inhibition of RUNX1- CBFβ-SMMHC protein-protein interaction as a novel therapeutic avenue for leukemia with inv(16) and AI-10-49 as a specific inhibitor of CBFβ-SMHHC oncoprotein. The discovery of AI-10-49 provides additional evidence that transcription factor drivers of cancer can be directly targeted. AI-10-49 belongs to a select group of protein-protein interaction inhibitors that has been shown to have specific and potent efficiency without toxicity in cancer therapy.
Mechanism of action of AI-10-49:
The mechanism of action of AI-10-49 was recently elucidated by the Castilla laboratory at University of Massachusetts Medical School. Gene Set Enrichment Analysis of RNA-seq data from inv(16) AML cells treated with AI-10-49 identified the deregulation of a MYC signature, including cell cycle, ribosome biogenesis and metabolism. MYC shRNA knockdown induced apoptosis of inv(16) AML cells, and MYC overexpression partially rescued AI-10-49 induced apoptosis. Furthermore, mouse leukemia cells transduced with Myc shRNAs showed significant delay in leukemic latency upon transplantation, validating the requirement of MYC in inv(16) AML maintenance in vivo. Pharmacologic inhibition of MYC activity, using a combined treatment with AI-10-49 and the BET-family bromodomain inhibitor JQ1, revealed a strong synergy in inv(16) AML cells and a significant delay in leukemia latency in mice. ChIP-seq and ATAC-seq analysis revealed that inhibition of the CBFβ-SMHHC–RUNX1 protein–protein interaction by AI-10-49 results in increased RUNX1 occupancy at three MYC distal enhancers downstream from MYC transcription start site. Deletion of the RUNX1 binding site in these enhancers by genome editing (CRISPR/Cas9) reduced MYC transcript levels and the viability of inv(16) AML cells, indicating that each one of these enhancers plays a critical role in regulating MYC levels and sustaining the survival of inv(16) AML cells. Analysis of enhancer-promoter interactions by chromosome conformation capture carbon copy (5C) in inv(16) AML cells revealed that the three enhancers are physically connected with each other and to the MYC promoter. Analysis of chromatin immunoprecipitation revealed that AI-10-49 treatment results in the displacement of the SWI/SNF complex component BRG1 and RUNX1 mediated recruitment of polycomb-repressive complex 1 (PRC1) component RING1B at the three MYC enhancers. Taken together, these results demonstrate that AI-10-49 treatment induces an acute release of RUNX1, increases RUNX1 occupancy at MYC enhancers, and disrupts enhancer chromatin dynamics which in turn induces apoptosis by repressing MYC. Furthermore, this study suggests that combined treatment of inv(16) AML with AI-10-49 and BET-family inhibitors may represent a promising targeted therapy.
Protein-protein interaction inhibitors in cancer therapy:
Targeting protein-protein interaction with small molecule is known to be extremely difficult due to the fact that binding regions consist of wide, shallow surfaces. There are few protein-protein interaction inhibitors with specific and non-toxic effect in various cancer types. The first and best characterized protein-protein interaction inhibitor in cancer therapy is Nutlin. Nutlin inhibits the interaction between HDM2 and tumour suppressor p53. After the discovery of Nutlin, more than 20 small molecule inhibitors have been developed by academic institutes and pharmaceutical companies of which 8 inhibitors are under Phase 1 clinical trials. Other examples for protein-protein interaction inhibitors include JQ1 (inhibits the interaction between acetylated histones and BRD4); 79-6 (inhibits BCL6 BTB domain dimerization); MI-463 and MI-503 (inhibit Menin-MLL interaction) and ABT-737 (inhibits BCL2L1-BCL2 interaction). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Silverio García Lara**
Silverio García Lara:
Silverio García Lara is a researcher and head of AgroBio Unit and a professor of Nutri-Omics Group with the Monterrey Institute of Technology and Higher Studies, Campus Monterrey within the National School of Science. Silverio García-Lara obtained his PhD in Experimental Biology from the Autonomous Metropolitan University during which he develop a PhD stay the University of Ottawa in Canada and subsequently Postdoctoral studies at the International Center for Maize and Wheat Improvement, CIMMYT, Int.From 2006 to 2008 he was the head of Entomology Unit at the Global Maize Program of CIMMYT and in 2009 he was invited as a visiting scientist at Global ICARDA-CIMMYT-IITA Maize Program. He is currently an Associate Professor and Senior Scientist at the National School of Science and Technology at Tecnologico de Monterrey. Among its main achievements he had developed, improved and characterized storage pests resistant corn and corn with nutraceutical properties. He has developed several comprehensive technologies of global food security to reduce post-harvest problems for Latin America, Africa and Asia. García Lara has worked on ways reduced the amount of food loss in storage, especially corn, coffee and rice. He and two students have also discovered anti-cancer properties in Mexican oregano and corn . He has received financial support from agencies and foundations such as FEMSA, CONACYT, SAGARPA, USDA-USA, CIDA-CANADA, CIMMYT MasAgro, GrainPro, Monsanto, and Kelloggs, among others.
Silverio García Lara:
His work in molecular breeding, postharvest biotechnology and nutraceutical bio-characterization has been recognized and awarded by the Canadian Foundation for the International Conference on Agricultural Biotechnology (ABIC), The Consultative Group on International Agriculture (CGIAR), AGROBIO Mexico and the Institute of Nutrition of BIMBO Group. He was recognized at the second Convención Latinoamericana hermetic Storage in Guatemala for the testing of special plastic bags for grain storage. In 2012 he got the Teaching and Research Award by Tecnologico de Monterrey. He is a regular member of the Mexican Academy of Science since 2014.Mexico's Sistema Nacional de Investigadores has recognized his work with Level 3 membership.
Silverio García Lara:
García Lara has more than 200 abstracts presented at national and international conferences and currently has more than 100 publications, ten book chapters, three books, four patents, and dozens of outreach lectures at various national and international forums. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Comparison of stylesheet languages**
Comparison of stylesheet languages:
In computing, the two primary stylesheet languages are Cascading Style Sheets (CSS) and the Extensible Stylesheet Language (XSL). While they are both called stylesheet languages, they have very different purposes and ways of going about their tasks.
Cascading Style Sheets:
CSS is designed around styling a document, structured in a markup language, HTML and XML (including XHTML and SVG) documents. It was created for that purpose. The code CSS is non-XML syntax to define the style information for the various elements of the document that it styles.
The language to structure a document (markup language) is a prelimit to CSS. A markup language, like HTML and less XUL, may define some primitive elements to style a document, for example <emphasis> to bold. CSS post styles a document to "screen media" or "paged media".
Cascading Style Sheets:
Screen media, displayed as a single page (possibly with hyperlinks), that has a fixed horizontal width but a virtually unlimited vertical height. Scrolling is often the method of choice for viewing parts of screen media. This is in contrast to "paged media", which has multiple pages, each with specific fixed horizontal and vertical dimensions. To style paged media involves a variety of complexities that screen media does not. Since CSS was designed originally for screen media, its paged facilities lacked.
Cascading Style Sheets:
CSS version 3.0 provides new features that allow CSS to more adequately style documents for paged display.
Extensible Stylesheet Language:
XSL has evolved drastically from its initial design into something very different from its original purpose. The original idea for XSL was to create an XML-based styling language directed toward paged display media. The mechanism they used to accomplish this task was to divide the process into two distinct steps.
First, the XML document would be transformed into an intermediate form. The process for performing this transformation would be governed by the XSL stylesheet, as defined by the XSL specification. The result of this transformation would be an XML document in an intermediate language, known as XSL-FO (also defined by the XSL specification).
Extensible Stylesheet Language:
However, in the process of designing the transformation step, it was realized that a generic XML transformation language would be useful for more than merely creating a presentation of an XML document. As such, a new working group was split off from the XSL working group, and the XSL Transformations (XSLT) language became something that was considered separate from the styling information of the XSL-FO document. Even that split was expanded when XPath became its own separate specification, though still strongly tied to XSLT.
Extensible Stylesheet Language:
The combination of XSLT and XSL-FO creates a powerful styling language, though much more complex than CSS. XSLT is a Turing complete language, while CSS is not; this demonstrates a degree of power and flexibility not found in CSS. Additionally, XSLT is capable of creating content, such as automatically creating a table of contents just from chapters in a book, or removing/selecting content, such as only generating a glossary from a book. XSLT version 1.0 with the EXSLT extensions, or XSLT version 2.0 is capable of generating multiple documents as well, such as dividing the chapters in a book into their own individual pages. By contrast, a CSS can only selectively remove content by not displaying it.
Extensible Stylesheet Language:
XSL-FO is unlike CSS in that the XSL-FO document stands alone. CSS modifies a document that is attached to it, while the XSL-FO document (usually the result of the transformation by XSLT of the original document) contains all of the content to be presented in a purely presentational format. It has a wide range of specification options with regard to paged formatting and higher-quality typesetting. But it does not specify the pages themselves. The XSL-FO document must be passed through an XSL-FO processor utility that generates the final paged media, much like HTML+CSS must pass through a web browser to be displayed in its formatted state.
Extensible Stylesheet Language:
The complexity of XSL-FO is a problem, largely because implementing an FO processor is very difficult. CSS implementations in web browsers are still not entirely compatible with one another, and it is much simpler to write a CSS processor than an FO processor. However, for richly specified paged media, such complexity is ultimately required in order to be able to solve various typesetting problems. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**EZCast**
EZCast:
EZCast is a line of digital media players, built by Actions Microelectronics, that allows users to mirror media content from smart devices, including mobile devices, personal computers, and project to high-definition televisions.
History:
The first generation of EZCast was developed in 2013, shipped 1 million units within a year, and accumulated more than 2 million EZCast app users worldwide. The latest device in the family, called EZCast 4K, was launched in November 2016 which supports 4K HEVC video streaming.EZCast technology is built into a dongle that interacts with EZCast app to stream content from smart devices, and it works across Android, ChromeOS, iOS, macOS, Windows and Windows Phone.EZCast SDK has been released to enable third party development on Android and iOS.In 2018 became possible to voice control EZCast 2 and EZCast 4K devices using Google Assistant. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Dimethandrolone**
Dimethandrolone:
Dimethandrolone (DMA), also known by its developmental code name CDB-1321, is an experimental androgen/anabolic steroid (AAS) and progestogen medication which is under investigation for potential clinical use.Dimethandrolone is an AAS, and hence is an agonist of the androgen receptor, the biological target of androgens like testosterone. It is also a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. Due to its androgenic and progestogenic activity, dimethandrolone has antigonadotropic effects. It has no estrogenic activity.Dimethandrolone was first described in 1997. It was developed by the Contraceptive Development Branch of the National Institute of Child Health and Human Development, an agency in the United States government.An ester and prodrug of dimethandrolone, dimethandrolone undecanoate (DMAU) (CDB-4521), is under development for potential use as a birth control pill for men and in androgen replacement therapy for men.
Pharmacology:
Pharmacodynamics Dimethandrolone is an AAS, though it has also been described as a selective androgen receptor modulator (SARM). As an AAS, it is a potent agonist of the androgen receptor (AR).Unlike testosterone and various other AAS, dimethandrolone is not metabolized by 5α-reductase. In addition, the 5α-reduced derivative of dimethandrolone, 5α-dihydrodimethandrolone (5α-DHDMA), possesses only 30 to 40% of the potency of dimethandrolone as an agonist of the AR, indicating that dimethandrolone does not require potentiation by 5α-reductase for its activity as an AAS and that even if it were a substrate for 5α-reductase, it would not be potentiated in androgenic tissues like the skin and prostate. As such, dimethandrolone and ester prodrugs of it like DMAU are thought to have a reduced risk of androgenic side effects and conditions such as benign prostatic hyperplasia, prostate cancer, pattern scalp hair loss, and acne relative to testosterone and certain other AAS.Dimethandrolone is not a substrate for aromatase, and for this reason, is not converted into the corresponding aromatic A-ring derivative 7α,11β-dimethylestradiol, a potent estrogen. As such, dimethandrolone is not estrogenic. This is in contrast to nandrolone, which, although its rate of aromatization into the estrogen estradiol is reduced relative to that of testosterone, is still converted to a significant extent.Similarly to nandrolone and other 19-nortestosterone derivatives, dimethandrolone is a potent progestogen in addition to AAS. This property may serve to augment its antigonadotropic activity, which in turn may improve its effectiveness as an antispermatogenic agent and male contraceptive. This is salient and potentially beneficial as male contraceptives based on androgens alone have failed to produce satisfactory azoospermia in around one-third of men.Dimethandrolone has shown minimal potential for hepatotoxicity in animal studies, which is in accordance with the fact that it is not a 17α-alkylated AAS.
Chemistry:
Dimethandrolone, also known as 7α,11β-dimethyl-19-nortestosterone or as 7α,11β-dimethylestr-4-en-17β-ol-3-one, is a synthetic estrane steroid and a non-17α-alkylated derivative of nandrolone (19-nortestosterone).
Esters Aside from the C17β undecanoate ester of dimethandrolone, DMAU (CDB-4521), a few other esters, such as dimethandrolone buciclate (CDB-4386A) and dimethandrolone dodecylcarbonate (CDB-4730), have also been developed.
Analogues Other AAS that are closely related to dimethandrolone (besides nandrolone) include trestolone (also known as 7α-methyl-19-nortestosterone (MENT)) and 11β-methyl-19-nortestosterone (11β-MNT) and their respective C17β esters trestolone acetate and 11β-MNT dodecylcarbonate (11β-MNTDC).
History:
A patent for dimethandrolone was filed in 1997 and was granted in 1999. Subsequently, a patent for DMAU and dimethandrolone buciclate was filed in 2002 and was granted to the United States government in 2003. Dimethandrolone was developed under the code name CDB-1321 by the Contraceptive Development Branch of the National Institute of Child Health and Human Development, one of the National Institutes of Health in the United States Department of Health and Human Services. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Electric heating**
Electric heating:
Electric heating is a process in which electrical energy is converted directly to heat energy. Common applications include space heating, cooking, water heating and industrial processes. An electric heater is an electrical device that converts an electric current into heat. The heating element inside every electric heater is an electrical resistor, and works on the principle of Joule heating: an electric current passing through a resistor will convert that electrical energy into heat energy. Most modern electric heating devices use nichrome wire as the active element; the heating element, depicted on the right, uses nichrome wire supported by ceramic insulators.
Electric heating:
Alternatively, a heat pump can achieve around 150% - 600% efficiency for heating, or COP 1.5 - 6.0 Coefficient of performance, because it uses electric power only for transferring existing thermal energy. The heat pump uses an electric motor to drive a reversed refrigeration cycle, that draws heat energy from an external source such as the ground or outside air (or the interior of a refrigerator) and directs that heat into the space to be warmed (in case of a fridge, the kitchen). This makes much better use of electric energy than direct electric heating, but requires much more expensive equipment, plus plumbing. Some heating systems can be operated in reverse for air conditioning so that the interior space is cooled and even hotter air or water is discharged outside or into the ground.
Space heating:
Space heating is used to warm the interiors of buildings. Space heaters are useful in places where air-handling is difficult, such as in laboratories. Several methods of electric space heating are used.
Space heating:
Infrared radiant heaters Electric infrared radiant heating uses heating elements that reach a high temperature. The element is usually packaged inside a glass envelope resembling a light bulb and with a reflector to direct the energy output away from the body of the heater. The element emits infrared radiation that travels through air or space until it hits an absorbing surface, where it is partially converted to heat and partially reflected. This heat directly warms people and objects in the room, rather than warming the air. This style of heater is particularly useful in areas through which unheated air flows. They are also ideal for basements and garages where spot heating is desired. More generally, they are an excellent choice for task-specific heating.
Space heating:
Radiant heaters operate silently and present the greatest potential danger of ignition of nearby furnishings due to the focused intensity of their output and lack of overheat protection. In the United Kingdom, these appliances are sometimes called electric fires, because they were originally used to replace open fires.
The active medium of the heater depicted in this section is a coil of nichrome resistance wire inside a fused silica tube, open to the atmosphere at the ends, although models exist where the fused silica is sealed at the ends and the resistance alloy is not nichrome.
Space heating:
Convection heaters In a convection heater, the heating element heats the air in contact with it by thermal conduction. Hot air is less dense than cool air, so it rises due to buoyancy, allowing more cool air to flow in to take its place. This sets up a convection current of hot air that rises from the heater, heats up the surrounding space, cools and then repeats the cycle. These heaters are sometimes filled with oil or thermal fluid. They are ideally suited for heating a closed space. They operate silently and have a lower risk of ignition hazard if they make unintended contact with furnishings compared to radiant electric heaters.
Space heating:
Fan heaters A fan heater, also called a forced convection heater, is a kind of convection heater that includes an electric fan to speed up the airflow. They operate with considerable noise caused by the fan. They have a moderate risk of ignition hazard if they make unintended contact with furnishings. Their advantage is that they are more compact than heaters that use natural convection and are also cost-efficient for portable and small room heating systems.
Space heating:
Storage heating A storage heating system takes advantage of cheaper electricity prices, sold during low demand periods such as overnight. In the United Kingdom, this is branded as Economy 7. The storage heater stores heat in clay bricks, then releases it during the day when required. Newer storage heaters are able to be used with various tariffs. Whilst they can still be used with economy 7, they can be used with day-time tariffs. This is due to the modern design features that are added during manufacturing. Alongside new designs the use of a thermostat or sensor has improved the efficiency of the storage heater. A thermostat or sensor is able to read the temperature of the room, and change the output of the heater accordingly.
Space heating:
Water can also be used as a heat-storage medium.
Space heating:
Domestic electrical underfloor heating An electric underfloor heating system has heating cables embedded in the floor. Current flows through a conductive heating material, supplied either directly from the line voltage (120 or 240 volts) or at low voltage from a transformer. The heated cables warm the flooring by direct conduction and will switch off once it reaches the temperature set by the floor thermostat. A warmer floor surface radiates heat to colder surrounding surfaces (ceiling, walls, furniture.) which absorb heat and reflects all non absorbed heat to yet other still cooler surfaces. The cycle of radiation, absorption and reflection starts slowly and slows down slowly nearing set point temperatures and ceases to take place once equilibrium is reached all-round. A floor thermostat or a room thermostat or combination controls the floor on/off. In the process of radiant heating a thin layer of air which is in touch with the warmed surfaces also absorbs some heat and this creates a little convection (air circulation). Contrary to belief people are not heated by this warmed circulating air or convection (convection has a cooling effect) but are heated by the direct radiation of the source and reflection of its surrounds.
Space heating:
Comfort is reached at lower air temperature due to eliminating circulating air. Radiant heating experiences highest comfort levels as people's own energy (± 70 Watt for an adult) (must radiate out in heating season) is in balance with its surrounds. Compared to convection heating system based on academic research the air temperatures may be lowered by up to 3 degrees.
Space heating:
One variation is using tubes filled with circulating hot water as heat source for warming the floor. The heating principle remains the same. Both old style electric and warm water (hydronic) underfloor heating systems embedded in the floor construction are slow and cannot respond to external weather changes or internal demand/lifestyle requirements.
The latest variant places specialized electric heating systems and blankets directly under the floor-decor and on top of additional insulation all placed on top of construction floors. Construction floors stay cold.
The principle change of heat source positioning allows it to respond within minutes to changing weather and internal demand requirements such as life style being in/out, at work, rest, sleep, more people present/cooking, etc.
Space heating:
Lighting system In large office towers, the lighting system is integrated along with the heating and ventilation system. Waste heat from fluorescent lamps is captured in the return air of the heating system; in large buildings a substantial part of the annual heating energy is supplied by the lighting system. However, this waste heat becomes a liability when using air conditioning. Such expenses can be avoided by integrating an energy efficient lighting system that also creates an electric heat source.
Space heating:
Heat pumps A heat pump uses an electrically driven compressor to operate a refrigeration cycle that extracts heat energy from outdoor air, the ground or ground water, and moves that heat to the space to be warmed. A liquid contained within the evaporator section of the heat pump boils at low pressure, absorbing heat energy from the outdoor air or the ground. The vapor is then compressed by a compressor and piped into a condenser coil within the building to be heated. The heat from the hot dense gas is absorbed by the air in the building (and sometimes also used for domestic hot water) causing the hot working fluid to condense back into a liquid. From there the high pressure fluid is passed back to the evaporator section where it expands through an orifice and into the evaporator section, completing the cycle. In the summer months, the cycle can be reversed to move heat out of the conditioned space and to the outside air.
Space heating:
Heat pumps may obtain low-grade heat from the outdoor air in mild climates. In areas with average winter temperatures well below freezing, ground source heat pumps are more efficient than air source heat pumps because they can extract residual solar heat stored in the ground at warmer temperatures than is available from cold air. According to the US EPA, geothermal heat pumps can reduce energy consumption up to 44% compared with air source heat pumps and up to 72% compared with electric resistance heating. The high purchase price of a heat pump vs resistance heaters may be offset when air conditioning is also needed.
Liquid heating:
Immersion heater An immersion heater has an electrical resistance heating element encased in a tube, placed in the water (or other fluid) to be heated. The heating element might be inserted directly into the liquid, or installed inside a metal pipe to protect against corrosion and facilitate maintenance. Portable immersion heaters may not have a control thermostat, since they are intended to be used only briefly and under control of an operator.
Liquid heating:
For domestic hot water supply, or industrial process hot water, permanently installed heating elements in an insulated hot water tank may be used, controlled by a thermostat to regulate temperature. Household units may be rated only a few kilowatts. Industrial water heaters may reach 2000 kilowatts. Where off-peak electric power rates are available, hot water may be stored to use when required.
Liquid heating:
Electric shower and tankless heaters also use an immersion heater (shielded or naked) that is turned on with the flow of water. A group of separate heaters can be switched to offer different heating levels. Electric showers and tankless heaters usually use from 3 to 10.5 kilowatts.
Liquid heating:
Minerals present in the water supply may precipitate out of solution and form a hard scale on the heating element surface, or may fall to the bottom of the tank and clog water flow. Maintenance of water heating equipment may require periodic removal of accumulated scale and sediment. Where water supplies are known to be highly mineralized, scale production can be reduced by using low-watt-density heating elements.
Liquid heating:
Circulation heaters Circulation heaters or "direct electric heat exchangers" (DEHE) use heating elements inserted into a "shell side" medium directly to provide the heating effect. All of the heat generated by the electric circulation heater is transferred into the medium, thus an electric heater is 100 percent efficient. Direct electric heat exchangers or "circulation heaters" are used to heat liquids and gases in industrial processes.
Liquid heating:
Electrode heater With an electrode heater, there is no wire-wound resistance and the liquid itself acts as the resistance. This has potential hazards, so the regulations governing electrode heaters are strict.
Environmental and efficiency aspects:
The efficiency of any system depends on the definition of the boundaries of the system. For an electrical energy customer the efficiency of electric space heating is 100% because all purchased energy is converted to heat. However, if a power plant supplying electricity is included, the overall efficiency drops drastically. For example, a fossil-fuel power station only delivers 3-5 units of electrical energy for every 10 units of fuel energy released. Even though the electric heater is 100% efficient, the amount of fuel needed to produce the heat is more than if the fuel were burned in a furnace or boiler at the building being heated. If the same fuel could be used for space heating by a consumer, it would be more efficient overall to burn the fuel at the end user's building. On the other hand, replacing electric heating with fossil fuel burning heaters, isn't necessarily good as it removes the ability to have renewable electric heating, this can be achieved by sourcing the electricity from a renewable source.
Environmental and efficiency aspects:
Variations between countries generating electrical power affect concerns about efficiency and the environment. In 2015 France generated only 6% of its electricity from fossil fuels, while Australia sourced over 86% of its electricity from fossil fuels. The cleanliness and efficiency of electricity are dependent on the source.
In Sweden the use of direct electric heating has been restricted since the 1980s for this reason, and there are plans to phase it out entirely – see Oil phase-out in Sweden – while Denmark has banned the installation of direct electric space heating in new buildings for similar reasons.
In the case of new buildings, low-energy building techniques can be used which can virtually eliminate the need for heating, such as those built to the Passivhaus standard.
Environmental and efficiency aspects:
In Quebec, however, electric heating is still the most popular form of home heating. According to a 2003 Statistics Canada survey, 68% of households in the province use electricity for space heating. More than 90% of all power consumed in Quebec is generated by hydroelectric dams, which have low greenhouse gases emissions compared to fossil-fuel power stations. Low and stable rates are charged by Hydro-Québec, the provincially owned utility.In recent years there has been a major trend for countries to generate low-carbon electricity from renewable sources, adding to nuclear power and hydro-electric power which are long-standing low-carbon sources. For example, the carbon footprint of UK electricity per kWh in 2019 was less than half that in 2010. However, because of high capital cost, the cost of electricity has not fallen and is typically 2-3 times that of burning fuel. Hence, direct electric heating may now give a similar carbon footprint to gas- or oil-fired heating, but the cost remains higher, though cheaper off-peak tariffs can reduce this effect.
Environmental and efficiency aspects:
To provide heat more efficiently, an electrically driven heat pump can raise the indoor temperature by extracting energy from the ground, the outside air, or waste streams such as exhaust air. This can cut the electricity consumption to as little as 35% of that used by resistive heating.
Where the primary source of electrical energy is hydroelectric, nuclear, or wind, transferring electricity via the grid can be convenient, since the resource may be too distant for direct heating applications (with the notable exception of solar thermal energy).
The electrification of heat of space and water heating is increasingly proposed as a way forward to decarbonise the current energy system, particularly with heat pumps. In case of large-scale electrification, impacts on the electricity grid due to potential increase in peak electricity demand and exposure to extreme weather events needs to be considered.
Economic aspects:
The operation of electric resistance heaters to heat an area for long periods is costly in many regions. However, intermittent or partial day use can be more cost efficient than whole building heating due to superior zonal control.
Economic aspects:
For example: A lunch room in an office setting has limited hours of operation. During low-use periods a "monitor" level of heat (50 °F or 10 °C) is provided by the central heating system. Peak use times between the hours of 11:00 and 14:00 are heated to "comfort levels" (70 °F or 21 °C). Significant savings can be realized in overall energy consumption, since infrared radiation losses through thermal radiation are not as large with a smaller temperature gradient both between this space and unheated outside air, as well as between the refrigerator and the (now cooler) lunch room.
Economic aspects:
Economically, electric heat can be compared to other sources of home heating by multiplying the local cost per kilowatt hour for electricity by the number of kilowatts the heater uses. E.g.: 1500-watt heater at 12 cents per kilowatt hour 1.5×12=18 cents per hour. When comparing to burning fuel it may be useful to convert kilowatt hours to BTUs: 1.5 kWh × 3412.142=5118 BTU.
Industrial electric heating:
Electric heating is widely used in industry.Advantages of electric heating methods over other forms include precision control of temperature and distribution of heat energy, combustion not used to develop heat, and the ability to attain temperatures not readily achievable with chemical combustion. Electric heat can be accurately applied at the precise point needed in a process, at high concentration of power per unit area or volume. Electric heating devices can be built in any required size and can be located anywhere within a plant. Electric heating processes are generally clean, quiet, and do not emit much byproduct heat to the surroundings. Electrical heating equipment has a high speed of response, lending it to rapid-cycling mass-production equipment.
Industrial electric heating:
The limitations and disadvantages of electric heating in industry include the higher cost of electrical energy compared to direct use of fuel, and the capital cost of both the electric heating apparatus itself and the infrastructure required to deliver large quantities of electrical energy to the point of use. This may be somewhat offset by in-plant (on-site) efficiency gains in using less energy overall to achieve the same result.
Industrial electric heating:
Design of an industrial heating system starts with assessment of the temperature required, the amount of heat required, and the feasible modes of transferring heat energy. In addition to conduction, convection and radiation, electrical heating methods can use electric and magnetic fields to heat material.
Industrial electric heating:
Methods of electric heating include resistance heating, electric arc heating, induction heating, and dielectric heating. In some processes (for example, arc welding), electric current is directly applied to the workpiece. In other processes, heat is produced within the workpiece by induction or dielectric losses. As well, heat can be produced then transferred to the work by conduction, convection or radiation.
Industrial electric heating:
Industrial heating processes can be broadly categorized as low-temperature (to about 400 °C or 752 °F), medium-temperature (between 400 and 1,150 °C or 752 and 2,102 °F), and high-temperature (beyond 1,150 °C or 2,102 °F). Low-temperature processes include baking and drying, curing finishes, soldering, molding and shaping plastics. Medium temperature processes include melting plastics and some non-metals for casting or reshaping, as well as annealing, stress-relieving and heat-treating metals. High-temperature processes include steelmaking, brazing, welding, casting metals, cutting, smelting and the preparation of some chemicals. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Cybernetics: Or Control and Communication in the Animal and the Machine**
Cybernetics: Or Control and Communication in the Animal and the Machine:
Cybernetics: Or Control and Communication in the Animal and the Machine is a book written by Norbert Wiener and published in 1948. It is the first public usage of the term "cybernetics" to refer to self-regulating mechanisms. The book laid the theoretical foundation for servomechanisms (whether electrical, mechanical or hydraulic), automatic navigation, analog computing, artificial intelligence, neuroscience, and reliable communications.
Cybernetics: Or Control and Communication in the Animal and the Machine:
A second edition with minor changes and two additional chapters was published in 1961.
Reception:
The book aroused a considerable amount of public discussion and comment at the time of publication, unusual for a predominantly technical subject.
Reception:
"[A] beautifully written book, lucid, direct, and, despite its complexity, as readable by the layman as the trained scientist, if the former is willing to forego attempts to understand mathematical formulas." "One of the most influential books of the twentieth century, Cybernetics has been acclaimed as one of the 'seminal works' comparable in ultimate importance to Galileo or Malthus or Rousseau or Mill." "Its scope and implications are breathtaking, and leaves the reviewer with the conviction that it is a major contribution to contemporary thought." "Cybernetics... is worthwhile for its historical value alone. But it does much more by inspiring the contemporary roboticist to think broadly and be open to innovative applications."The public interest aroused by this book inspired Wiener to address the sociological and political issues raised in a book targeted at the non-technical reader, resulting in the publication in 1950 of The Human Use of Human Beings.
Table of contents:
Introduction 1. Newtonian and Bergsonian Time 2. Groups and Statistical Mechanics 3. Time Series, Information, and Communication 4. Feedback and Oscillation 5. Computing Machines and the Nervous System 6. Gestalt and Universals 7. Cybernetics and Psychopathology 8. Information, Language, and Society Supplementary chapters in the second edition 9. On Learning and Self-Reproducing Machines 10. Brain Waves and Self-Organising Systems
Synopsis:
Introduction Wiener recounts that the origin of the ideas in this book is a ten-year-long series of meetings at the Harvard Medical School where medical scientists and physicians discussed scientific method with mathematicians, physicists and engineers. He details the interdisciplinary nature of his approach and refers to his work with Vannevar Bush and his differential analyzer (a primitive analog computer), as well as his early thoughts on the features and design principles of future digital calculating machines. He traces the origins of cybernetic analysis to the philosophy of Leibniz, citing his work on universal symbolism and a calculus of reasoning.
Synopsis:
Newtonian and Bergsonian Time The theme of this chapter is an exploration of the contrast between time-reversible processes governed by Newtonian mechanics and time-irreversible processes in accordance with the Second Law of Thermodynamics. In the opening section he contrasts the predictable nature of astronomy with the challenges posed in meteorology, anticipating future developments in Chaos theory. He points out that in fact, even in the case of astronomy, tidal forces between the planets introduce a degree of decay over cosmological time spans, and so strictly speaking Newtonian mechanics do not precisely apply.
Synopsis:
Groups and Statistical Mechanics This chapter opens with a review of the – entirely independent and apparently unrelated – work of two scientists in the early 20th century: Willard Gibbs and Henri Lebesgue. Gibbs was a physicist working on a statistical approach to Newtonian dynamics and thermodynamics, and Lebesgue was a pure mathematician working on the theory of trigonometric series. Wiener suggests that the questions asked by Gibbs find their answer in the work of Lebesgue. Wiener claims that the Lebesgue integral had unexpected but important implications in establishing the validity of Gibbs' work on the foundations of statistical mechanics. The notions of average and measure in the sense established by Lebesgue were urgently needed to provide a rigorous proof of Gibbs' ergodic hypothesis.The concept of entropy in statistical mechanics is developed, and its relationship to the way the concept is used in thermodynamics. By an analysis of the thought experiment Maxwell's demon, he relates the concept of entropy to that of information.
Synopsis:
Time Series, Information, and Communication This is one of the more mathematically intensive chapters in the book. It deals with the transmission or recording of a varying analog signal as a sequence of numerical samples, and lays much of the groundwork for the development of digital audio and telemetry over the past six decades. It also examines the relationship between bandwidth, noise, and information capacity, as developed by Wiener in collaboration with Claude Shannon. This chapter and the next one form the core of the foundational principles for the developments of automation systems, digital communications and data processing which have taken place over the decades since the book was published.
Synopsis:
Feedback and Oscillation This chapter lays down the foundations for the mathematical treatment of negative feedback in automated control systems. The opening passage illustrates the effect of faulty feedback mechanisms by the example of patients with various forms of ataxia. He then discusses railway signalling, the operation of a thermostat, and a steam engine centrifugal governor. The rest of the chapter is mostly taken up with the development of a mathematical formulation of the operation of the principles underlying all of these processes. More complex systems are then discussed such as automated navigation, and the control of non-linear situations such as steering on an icy road. He concludes with a reference to the homeostatic processes in living organisms.
Synopsis:
Computing Machines and the Nervous System This chapter opens with a discussion of the relative merits of analog computers and digital computers (which Wiener referred to as analogy machines and numerical machines), and maintains that digital machines will be more accurate, electronic implementations will be superior to mechanical or electro-mechanical ones, and that the binary system is preferable to other numerical scales. After discussing the need to store both the data to be processed and the algorithms which are employed for processing that data, and the challenges involved in implementing a suitable memory system, he goes on to draw the parallels between binary digital computers and the nerve structures in organisms.
Synopsis:
Among the mechanisms that he speculated for implementing a computer memory system was "a large array of small condensers [ie capacitors in today's terminology] which could be rapidly charged or discharged", thus prefiguring the essential technology of modern dynamic random-access memory chips.
Virtually all of the principles which Wiener enumerated as being desirable characteristics of calculating and data processing machines have been adopted in the design of digital computers, from the early mainframes of the 1950s to the latest microchips.
Synopsis:
Gestalt and Universals This brief chapter is a philosophical enquiry into the relationship between the physical events in the central nervous system and the subjective experiences of the individual. It concentrates principally on the processes whereby nervous signals from the retina are transformed into a representation of the visual field. It also explores the various feedback loops involved in the operation of the eyes: the homeostatic operation of the retina to control light levels, the adjustment of the lens to bring objects into focus, and the complex set of reflex movements to bring an object of attention into the detailed vision area of the fovea.
Synopsis:
The chapter concludes with an outline of the challenges presented by attempts to implement a reading machine for the blind.
Synopsis:
Cybernetics and Psychopathology Wiener opens this chapter with the disclaimers that he is neither a psychopathologist nor a psychiatrist, and that he is not asserting that mental problems are failings of the brain to operate as a computing machine. However, he suggests that there might be fruitful lines of enquiry opened by considering the parallels between the brain and a computer. (He employed the archaic-sounding phrase "computing machine", because at the time of writing the word "computer" referred to a person who is employed to perform routine calculations). He then discussed the concept of 'redundancy' in the sense of having two or three computing mechanisms operating simultaneously on the same problem, so that errors may be recognised and corrected.
Synopsis:
Information, Language, and Society Starting with an outline of the hierarchical nature of living organisms, and a discussion of the structure and organisation of colonies of symbiotic organisms, such as the Portuguese Man o' War, this chapter explores the parallels with the structure of human societies, and the challenges faced as they scale and complexity of society increases.
Synopsis:
The chapter closes with speculation about the possibility of constructing a chess-playing machine, and concludes that it would be conceivable to build a machine capable of a standard of play better than most human players but not at expert level. Such a possibility seemed entirely fanciful to most commentators in the 1940s, bearing in mind the state of computing technology at the time, although events have turned out to vindicate the prediction – and even to exceed it.
Synopsis:
On Learning and Self-Reproducing Machines Starting with an examination of the learning process in organisms, Wiener expands the discussion to John von Neumann's theory of games, and the application to military situations. He then speculates about the manner in which a chess-playing computer could be programmed to analyse its past performances and improve its performance. This proceeds to a discussion of the evolution of conflict, as in the examples of matador and bull, or mongoose and cobra, or between opponents in a tennis game. He discusses various stories such as The Sorcerer's Apprentice, which illustrate the view that the literal-minded reliance on "magical" processes may turn out to be counter-productive or catastrophic. The context of this discussion was to draw attention to the need for caution in delegating to machines the responsibility for warfare strategy in an age of Nuclear weapons. The chapter concludes with a discussion of the possibility of self-replicating machines and the work of Professor Dennis Gabor in this area.
Synopsis:
Brain Waves and Self-Organising Systems This chapter opens with a discussion of the mechanism of evolution by natural selection, which he refers to as "phylogenetic learning", since it is driven by a feedback mechanism caused by the success or otherwise in surviving and reproducing; and modifications of behaviour over a lifetime in response to experience, which he calls "ontogenetic learning". He suggests that both processes involve non-linear feedback, and speculates that the learning process is correlated with changes in patterns of the rhythms of the waves of electrical activity that can be observed on an electroencephalograph. After a discussion of the technical limitations of earlier designs of such equipment, he suggests that the field will become more fruitful as more sensitive interfaces and higher performance amplifiers are developed and the readings are stored in digital form for numerical analysis, rather than recorded by pen galvanometers in real time - which was the only available technique at the time of writing. He then develops suggestions for a mathematical treatment of the waveforms by Fourier analysis, and draws a parallel with the processing of the results of the Michelson–Morley experiment which confirmed the constancy of the velocity of light, which in turn led Albert Einstein to develop the theory of Special Relativity. As with much of the other material in this book, these pointers have been both prophetic of future developments and suggestive of fruitful lines of research and enquiry.
Influence:
The book provided a foundation for research into electronic engineering, computing (both analog and digital), servomechanisms, automation, telecommunications and neuroscience. It also created widespread public debates on the technical, philosophical and sociological issues it discussed. And it inspired a wide range of books on various subjects peripherally related to its content.
The book introduced the word 'cybernetics' itself into public discourse.Maxwell Maltz titled his pioneering self-development work "Psycho-Cybernetics" in reference to the process of steering oneself towards a pre-defined goal by making corrections to behaviour. Much of the personal development industry and the Human potential movement is said to be derived from Maltz's work.
Cybernetics became a surprise bestseller and was widely read beyond the technical audience that Wiener had expected. In response he wrote The Human Use of Human Beings in which he further explored the social and psychological implications in a format more suited to the non-technical reader.
In 1954, Marie Neurath produced a children's book Machines which seem to Think [1], which introduced the concepts of Cybernetics, control systems and negative feedback in an accessible format. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Organic search results**
Organic search results:
In Web search engines, organic search results are the query results which are calculated strictly algorithmically, and not affected by advertiser payments. They are distinguished from various kinds of sponsored results, whether they are explicit pay per click advertisements, shopping results, or other results where the search engine is paid either for showing the result, or for clicks on the result.
Background:
The Google, Yahoo!, Bing and Sogou search engines insert advertising on their search results pages. In U.S. law, advertising must be distinguished from organic results. This is done with various differences in background, text, link colors, and/or placement on the page. However, a 2004 survey found that a majority of search engine users could not distinguish the two.Because so few ordinary users (38% according to Pew Research Center) realized that many of the highest placed "results" on search engine results pages (SERPs) were ads, the search engine optimization industry began to distinguish between ads and natural results. The perspective among general users was that all results were, in fact, "results." So the qualifier "organic" was invented to distinguish non-ad search results from ads. It has been used since at least 2004.Because the distinction is important (and because the word "organic" has many metaphorical uses) the term is now in widespread use within the search engine optimization and web marketing industry. As of July 2009, the term "organic search" is now commonly used outside the specialist web marketing industry, even used frequently by Google (throughout the Google Analytics site, for instance).
Background:
Google claims their users click (organic) search results more often than ads, essentially rebutting the research cited above. A 2012 Google study found that 81% of ad impressions and 66% of ad clicks happen when there is no associated organic search result on the first page. Research has shown that searchers may have a bias against ads, unless the ads are relevant to the searcher's need or intent.The same report and others going back to 1997 by Pew show that users avoid clicking "results" they know to be ads.
Background:
According to a June 2013 study by Chitika, 9 out of 10 searchers don't go beyond Google's first page of organic search results, a claim often cited by the search engine optimization (SEO) industry to justify optimizing websites for organic search. Organic SEO describes the use of certain strategies or tools to elevate a website's content in the "free" search results.
Background:
Users can prevent ads in search results and list only organic results by using browser add-ons and plugins. Other browsers may have different tools developed for blocking ads.
Organic search engine optimization is the process of improving web sites' rank in organic search results. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Pyotraumatic dermatitis**
Pyotraumatic dermatitis:
Pyotraumatic dermatitis, also known as a hot spot or acute moist dermatitis, is a common infection of the skin surface of dogs, particularly those with thick or long coats. It occurs following self-inflicted trauma of the skin. Pyotraumatic dermatitis rarely affects cats.
Signs:
The dog persistently licks, chews, scratches or rubs at a focal area of skin, which quickly causes hair loss. The skin becomes red, moist and weeps. The affected area is obviously defined and separate from the surrounding healthy skin and coat. Usually only one area of the skin is affected. The size of the affected area is variable. If the area is difficult for the dog to scratch, or if the disease is caught early, hair may still be present. Areas commonly affected include the rump above the tail, the head and neck near the ears, and the top and sides of the lumbar area.
Cause:
Pyotraumatic dermatitis is caused by self-inflicted trauma to the skin, which is incited by pain or irritation, such as infestation with fleas or lice, irritation from clippers, allergic skin diseases, diseases of the anal sacs, inflammation of the ear canal, foreign bodies or irritants within the coat, or pain in muscles or joints. Skin maceration from repeated wetting of the coat or moisture in the fur can also be an inciting cause. Flea infestations are the most common inciting factor.The inciting factor causes the dog to traumatize a small area of skin. The affected skin weeps (that is, it exudes serum), and this moist surface layer of skin can become colonized by bacteria, although the skin itself is not infected. The affected area is usually painful, as nerve endings are exposed when the surface of the skin is eroded. Hair which remains in the affected area holds in the moisture and further irritates the skin surface. Continued itching by the dog can cause the affected area to enlarge rapidly in only a few hours.Pyotraumatic dermatitis is more common when the dog's environment is hot and humid. Dogs with thick undercoats or long fur are most commonly affected, but pyotraumatic dermatitis can occur in any dog. Commonly affected breeds include the Airedale Terrier, Akita, American Pit Bull Terrier, Basset Hound, Golden Retriever, Great Pyrenees, Labrador Retriever, Leonberger, Pembroke Welsh Corgi, Peruvian Inca Orchid (Peruvian Hairless Dog), Shiba Inu, and Xoloitzcuintle (Mexican hairless dog) as well as the German Shepherd and St. Bernard.
Treatment:
There are several aspects to treatment: breaking the "itch-scratch" cycle by clipping the fur and cleaning the skin; addressing the underlying painful or itchy condition which initially caused the animal to begin scratching; and relieving the dog's discomfort, for example with steroid medications.The hair in and around the affected area is clipped before the skin is cleaned with an antiseptic, rinsed, and dried. The dog may require sedation before the fur is clipped, as skin affected by pyotraumatic dermatitis can be painful.With treatment, pyotraumatic dermatitis resolves in 3–7 days, but can recur if the inciting factor is not addressed. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Dutch Design**
Dutch Design:
Dutch Design is a term used to denote an informal artistic school of design in the Netherlands, particularly product design. More specifically, the term refers to the design esthetic common to designers in the Netherlands.
History:
The Netherlands were primarily known for graphic design until the 1980s, when the term Dutch Design started to come into popular use.
History:
The term came to be closely identified with a group of Dutch product designers who have gained international recognition particularly from the 1990s onwards. These include Maarten Baas, Jurgen Bey, Richard Hutten, Hella Jongerius, Wieki Somers, Hester van Eeghen and Marcel Wanders, as well as internationally recognized design firms and collectives like Droog and Moooi which helped gain prominence for Dutch designers at major design events such as the Salone del Mobile in Milan.More broadly, the term could be extended to fashion designers such as Viktor & Rolf and architects such as Rem Koolhaas and Francine Houben.The emergence of an internationally recognized Dutch design scene has been fueled by a strong educational system for designers. The Design Academy Eindhoven has produced many well-known designers. In a 2003 article in The New York Times, Murray Moss, the owner of Moss, a design store in Manhattan, called it "without question, currently the best design academy in the world." Another well-known school is Gerrit Rietveld Academie in Amsterdam.
History:
A second contributing factor to the success of Dutch design is government support for new designers. Financial support from the Fonds BKVB (the Fund for Visual Arts, Design and Architecture), launched in 1988, has enabled design students to set themselves up as independent entrepreneurs right after graduation.Also playing an important role is the fact that design has become an integral part of product development in the Netherlands. Designers are included in the earliest phases of innovative processes and the production development cycle. The Dutch electronics company Philips, for instance, has around 450 people working on design at 12 offices around the world.The Dutch Design Awards are awarded annually during Dutch Design Week in Eindhoven.
Reception:
Dutch Design has been characterized as minimalist, experimental, innovative, quirky, and humorous."Dutch design is simple and powerful", according to Hugo van den Bos, strategy director of Dutch graphic design studio Koeweiden Postma. Author and journalist Tracy Metz notes that, "The Dutch have the ability to make fun of themselves. Also it's a matter of combining things that usually don't combine at all. Dutch designers are good in using materials that look worthless. The designers give them a new value."
Events:
Annual events Dutch Design Week (Eindhoven), including the Dutch Design Awards Past events Dutch Design Double (Amsterdam/Utrecht, 2009) Dutch Design Expo @ Shanghai International Creative Industry Week (Shanghai, 2008) Dutch Design Days (Belgium, 2008) Orange Alert (New York City, 2005) Via Milano New Dutch Design (Amsterdam), | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Booroola Merino**
Booroola Merino:
The Booroola is a Merino strain that has a high rate of multiple births.
Booroola's prolificacy was studied extensively by New Zealand researchers, who provided one of the first examples of the practical application of gene mapping in sheep, by mapping the Booroola gene to chromosome 6 .
History:
The Booroola Merino was started by Jack and Dick Seears of Booroola, Cooma using ewes from their Egelabra flock that gave multiple-births. The Seears gave the CSIRO a quintuplet ram in 1958, another in 1959 and a sextuplet ewe in 1960. In 1958, the CSIRO purchased 12 ewes (triplets or quadruplets) and a ewe who had given birth to triplets. When the Booroola flock was dispersed in 1965, the CSIRO purchased 91 mixed-age multiple-born ewes and moved their Booroola flock from Deniliquin to Armidale. The Egelabra and Mumblebone strains of the Merino can be traced to Gamboola; these were derived from Samuel Marsden's flock, and like Macarther's flock, Marsden's flock was based on South African Escurial, Cape and Bengal Sheep. The Bengal was a prolific sheep imported from Calcutta.
Notes:
Cottle, D.J. (1991). Australian Sheep and Wool Handbook. Melbourne, Australia: Inkata Press. pp. 20–23. ISBN 0-909605-60-2. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Waterballs**
Waterballs:
Waterballs are water toys that are played on the water surface with players interacting with the water toy and the water in any number of play patterns. Generally players throw waterballs at varying speeds across the water and air at varying angles to get the desired skip pattern. Play is generally between players and play patterns can involve a variety of apparatus and equipment, such as special pools with goals and watercourts.
In popular culture:
They are palm-sized waterballs that can travel as fast as they can be thrown. They can travel a great distance, even crossing large moving waterways. High-performance waterballs currently are not well known to the public as they have only been on the US market for a few years, having been introduced in the summer of 2008 with the launch of the Waboba Ball.Splash balls or water bombs are well known to the public and have been on the market in the US for years. They are designed for children and adults to play on a water surface. These are also more suitable for children and non-sport uses. Splash balls or water bombs are not high-performance waterballs or part of this discussion.
In popular culture:
There are a number of nerf-styled polo waterballs on the market that are smaller and softer than the regulation sport polo waterball. These are also more suitable for children and non-sport uses. These are polo and catch balls designed to play on the water surface however they are not high-performance waterballs or part of this discussion.
In popular culture:
Generally, high-performance waterballs have little friction on the water, they are relatively small in size and density making them generally a handball size. With a certain amount of force they skip, bounce and glide in a straight line on the water surface and can travel fast and long distance. They can be projected on the water between players at a range of 3– 200 feet as there is very little friction slow them on the water surface – particularly the sealed waterball. Each time they bounce, skip or roll on the water surface, the inertia is reduced by opposing forces of gravity, friction, surface tension, surface drag.
In popular culture:
Waterballs have traditionally been seen as a children's toy, with a number of manufacturers aiming for that particular market segment when introducing new products. The WaterRipper is being marketed as a kid's 4+ pool toy however it is also marketed as a high-performance action sports water ball. Most waterballs are sold in sporting goods, toy stores, outdoor stores and even food stores. The WaterRipper was launched in the United States in July 2010. The Waboba ball was initially marketed overseas, introduced in Scandinavia 2005 and in the United Kingdom in 2008. It is now sold worldwide.
Size, shape and materials:
The high-performance waterball is generally the size of a golf ball or stress ball designed for catching with a single hand. Different waterballs are made of different materials. Most high-performance waterballs are sealed balls and are made out of different types of rubber or neoprene with gel material center and polyurethane and Lycra jacket. The new generation waterball is water absorbing with fluid high-density particulate contents. There are patent pending designs for "high density" or "balanced density " materials in making the new generation waterballs.
Size, shape and materials:
High-performance waterballs come in different sizes and shapes. There are a handful of high-performance waterballs such as Waboba Ball, Water Bouncer, and the WaterRipper currently sold in the US. The sealed or water-absorbing, high-performance waterballs are typically 2 inches (51 mm) or larger and made of soft rubber generally with a neoprene single seam jacket. These balls are designed to bounce on the water surface.
Size, shape and materials:
The water absorbing waterball is the smallest of these high-performance waterballs. It is a collapsing bag or sack like a footbag with an Ultra Suede single seam cover and beaded fill with other water absorbing high-density materials. It is designed to skip and roll on water in a low profile skip pattern. It is less than 2 inches (51 mm) in diameter and it easily fits and collapses in a small child's hand. It looks and feels like a footbag or Hacky Sack. The water absorbing waterball like the Waboba Blast Ball and Water Ripper Ball are the only high-performance waterballs designed to absorb water.
Size, shape and materials:
Sealed waterballs vs. absorbent waterballs There are actually two types of high-performance waterballs. While all waterballs float on water, there are some that absorb water and others that are sealed. Sealed waterballs generally bounce higher because they simply repel & displace water. This type of waterball requires the players to have a grip or "timed grab" to catch the ball in flight and stop it. Because they bounce, they are generally hard to catch and often require two hands or a mitt or glove to control or catch them and more suited for adult play.
Size, shape and materials:
Conversely, the water absorbing collapsing waterball or waterbag is generally caught with one hand. Because it collapses on impact on the water or in your hand, it is easier and safer to play with young children ages 4+.
Size, shape and materials:
A sealed ball displaces and bounces on water as it interacts with the water surface. On impact with the water surface or a player's hand, the sealed waterball deforms and deflects and transfers its energy in the opposite direction as it bounces on impact. But a sealed waterball no matter how soft still maintains its spherical shape and ball like properties. The fluid dynamics and shape characteristics are relatively unchanged as the sealed waterball does not change its density.
Size, shape and materials:
As such, even tennis balls and handballs, stress balls can be used as waterball and perform, admitted poorly, depending on force and angle to the water etc.
Size, shape and materials:
Water absorbing waterballs or technically "waterbags", on the other hand, are designed for water and density exchange. Water freely permeates the whole ball, adding more weight and dynamic fluid density. The added weight makes this type of waterball skip and roll on water, rather than bounce. As a result, water absorbing high-performance waterballs travel shorter distances than sealed waterballs but they are easier to control and play with both in long and short range.
Size, shape and materials:
A waterbag exchanges its fluid density and transforms and conforms its shape and fluid contents on impact with a surface or plain. On impact with a surface such as water, the waterbag dissipates its energy dynamically as it interacts with the water surface exchanging fluid contents. This changes and balances the bag's density, mass and shape to conform to the water or surface it is performing on as it loses its velocity and comes to rest.
Size, shape and materials:
The beanbag-like design of the waterbag changes shape and conforms to a surface thus it collapses and is "slow acting" on impact. There is a significant difference between the physics of the sealed waterball and the water absorbing waterball or waterbag.
Size, shape and materials:
The waterbag exchanges its fluid contents on impact and it changes its shape as it collapses on impact. There is no bouncing or minimal bouncing action. Slow acting on impact is an intended design characteristic that is very pleasing and safe in high-speed play action. The "rolling action" of the waterbag that is referred to a "low skip profile" on the water surface that again collapses on impact with the water surface or player's hand. This makes the waterbag less active and easier to catch. The waterbag is both fast in action and slow acting on impact.
Safety issues:
Most waterballs currently available, while perfectly functional in water, are not designed to work well on a hard surface. This is particularly true with the new generation waterbag design.
Also, the impact of a waterball can hurt, and some waterballs have marks left on their skin.
However, there are several balls that address these issues by using softer and lighter material.
They have a low skip pattern and they are easy to catch and stay in the pool. Water absorbing waterbag designs are also designed in a way that makes them suitable for play in pools. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Huntingtin**
Huntingtin:
Huntingtin (Htt) is the protein coded for in humans by the HTT gene, also known as the IT15 ("interesting transcript 15") gene. Mutated HTT is the cause of Huntington's disease (HD), and has been investigated for this role and also for its involvement in long-term memory storage.It is variable in its structure, as the many polymorphisms of the gene can lead to variable numbers of glutamine residues present in the protein. In its wild-type (normal) form, the polymorphic locus contains 6-35 glutamine residues. However, in individuals affected by Huntington's disease (an autosomal dominant genetic disorder), the polymorphic locus contains more than 36 glutamine residues (highest reported repeat length is about 250). Its commonly used name is derived from this disease; previously, the IT15 label was commonly used.
Huntingtin:
The mass of huntingtin protein is dependent largely on the number of glutamine residues it has; the predicted mass is around 350 kDa. Normal huntingtin is generally accepted to be 3144 amino acids in size. The exact function of this protein is not known, but it plays an important role in nerve cells. Within cells, huntingtin may or may not be involved in signaling, transporting materials, binding proteins and other structures, and protecting against apoptosis, a form of programmed cell death. The huntingtin protein is required for normal development before birth. It is expressed in many tissues in the body, with the highest levels of expression seen in the brain.
Gene:
The 5'-end (five prime end) of the HTT gene has a sequence of three DNA bases, cytosine-adenine-guanine (CAG), coding for the amino acid glutamine, that is repeated multiple times. This region is called a trinucleotide repeat. The usual CAG repeat count is between seven and 35 repeats.
The HTT gene is located on the short arm (p) of chromosome 4 at position 16.3, from base pair 3,074,510 to base pair 3,243,960.
Protein:
Function The function of huntingtin (Htt) is not well understood but it is involved in axonal transport. Huntingtin is essential for development, and its absence is lethal in mice. The protein has no sequence homology with other proteins and is highly expressed in neurons and testes in humans and rodents. Huntingtin upregulates the expression of brain-derived neurotrophic factor (BDNF) at the transcription level, but the mechanism by which huntingtin regulates gene expression has not been determined. From immunohistochemistry, electron microscopy, and subcellular fractionation studies of the molecule, it has been found that huntingtin is primarily associated with vesicles and microtubules. These appear to indicate a functional role in cytoskeletal anchoring or transport of mitochondria. The Htt protein is involved in vesicle trafficking as it interacts with HIP1, a clathrin-binding protein, to mediate endocytosis, the trafficking of materials into a cell. Huntingtin has also been shown to have a role in the establishment in epithelial polarity through its interaction with RAB11A.
Protein:
Interactions Huntingtin has been found to interact directly with at least 19 other proteins, of which six are used for transcription, four for transport, three for cell signalling, and six others of unknown function (HIP5, HIP11, HIP13, HIP15, HIP16, and CGI-125). Over 100 interacting proteins have been found, such as huntingtin-associated protein 1 (HAP1) and huntingtin interacting protein 1 (HIP1), these were typically found using two-hybrid screening and confirmed using immunoprecipitation.
Protein:
Huntingtin has also been shown to interact with:
Mitochondrial dysfunction:
Huntingtin is a scaffolding protein in the ATM oxidative DNA damage response complex. Mutant huntingtin (mHtt) plays a key role in mitochondrial dysfunction involving the inhibition of mitochondrial electron transport, higher levels of reactive oxygen species and increased oxidative stress. The promotion of oxidative damage to DNA may contribute to Huntington's disease pathology.
Clinical significance:
Huntington's disease (HD) is caused by a mutated form of the huntingtin gene, where excessive (more than 36) CAG repeats result in formation of an unstable protein. These expanded repeats lead to production of a huntingtin protein that contains an abnormally long polyglutamine tract at the N-terminus. This makes it part of a class of neurodegenerative disorders known as trinucleotide repeat disorders or polyglutamine disorders. The key sequence which is found in Huntington's disease is a trinucleotide repeat expansion of glutamine residues beginning at the 18th amino acid. In unaffected individuals, this contains between 9 and 35 glutamine residues with no adverse effects. However, 36 or more residues produce an erroneous mutant form of Htt, (mHtt). Reduced penetrance is found in counts 36–39.Enzymes in the cell often cut this elongated protein into fragments. The protein fragments form abnormal clumps, known as neuronal intranuclear inclusions (NIIs), inside nerve cells, and may attract other, normal proteins into the clumps. The characteristic presence of these clumps in patients was thought to contribute to the development of Huntington disease. However, later research raised questions about the role of the inclusions (clumps) by showing the presence of visible NIIs extended the life of neurons and acted to reduce intracellular mutant huntingtin in neighboring neurons. One confounding factor is that different types of aggregates are now recognised to be formed by the mutant protein, including protein deposits that are too small to be recognised as visible deposits in the above-mentioned studies. The likelihood of neuronal death remains difficult to predict. Likely multiple factors are important, including: (1) the length of CAG repeats in the huntingtin gene and (2) the neuron's exposure to diffuse intracellular mutant huntingtin protein. NIIs (protein clumping) can be helpful as a coping mechanism—and not simply a pathogenic mechanism—to stem neuronal death by decreasing the amount of diffuse huntingtin. This process is particularly likely to occur in the striatum (a part of the brain that coordinates movement) primarily, and the frontal cortex (a part of the brain that controls thinking and emotions).
Clinical significance:
People with 36 to 40 CAG repeats may or may not develop the signs and symptoms of Huntington disease, while people with more than 40 repeats will develop the disorder during a normal lifetime. When there are more than 60 CAG repeats, the person develops a severe form of HD known as juvenile HD. Therefore, the number of CAG (the sequence coding for the amino acid glutamine) repeats influences the age of onset of the disease. No case of HD has been diagnosed with a count less than 36.As the altered gene is passed from one generation to the next, the size of the CAG repeat expansion can change; it often increases in size, especially when it is inherited from the father. People with 28 to 35 CAG repeats have not been reported to develop the disorder, but their children are at risk of having the disease if the repeat expansion increases. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Inertial audio effects controller**
Inertial audio effects controller:
An inertial audio effects controller is an electronic device that senses changes in acceleration, angular velocity and/or a magnetic field, and relays those changes to an effects controller. Transmitting the sensed data can be done via wired or wireless methods. To be of use the effects controller must be connected to an effect unit so that an effect can be modulated, or connected to a MIDI controller or musical keyboard. The Wah-Wah effect is a classic example of effect modulation.
Inertial audio effects controller:
An inertial audio effects controller can be compared with a traditional expression pedal to explain what it does. An inertial effects controller uses an inertial sensor to detect user directed changes, whereas a traditional expression pedal uses an electrically resistive element to detect changes. There are some advantages and disadvantages between the two. The main advantages of inertial control versus a traditional foot pedal, are an increased range of dynamic motion, remote control, finer modulation precision and software enabled features such as motion triggered ADSR envelopes and bi-directional motion control. The main disadvantages are the requirement for a power source and a more complicated setup.Due to their functional similarity with traditional expression pedals, they have been given the informal name, 'Expression box'.
Availability:
Conceivably any or all of the inertial sensors (accelerometer, gyroscope, magnetometer), could be used for effect modulation. However, currently the only commercially available products use acceleration sensing only or acceleration combined with angular velocity, as sensed by a gyroscope.
Future:
Inertial control of an audio device, wired or wireless, is a relatively recent and growing trend as technology advances have reduced pricing and size as well as improved usability and performance of the core components. Specifically the core components are an inertial device called a Mirco- Electro-Mechanical-System (MEMs), a microcontroller, and for wireless systems, a radio frequency transmitter/receiver. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Apoptozole**
Apoptozole:
Apoptozole is a drug that acts as a potent and selective inhibitor of the heat shock protein Hsp70, and was one of the first compounds developed to act at this target. It induces apoptosis in susceptible cells, and displays anti-cancer, anti-malarial and antiviral activity. The promising results in animal studies makes it likely that either apoptozole or compounds with similar modes of action will be further researched as potential therapeutics in the future. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Steel**
Steel:
Steel is an alloy of iron and carbon with improved strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels, which are resistant to corrosion and oxidation, typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, bicycles, machines, electrical appliances, furniture, and weapons.
Steel:
Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of carbon, other elements, and inclusions within the iron act as hardening agents that prevent the movement of dislocations.
Steel:
The carbon in typical steel alloys may contribute up to 2.14% of its weight. Varying the amount of carbon and many other alloying elements, as well as controlling their chemical and physical makeup in the final steel (either as solute elements, or as precipitated phases), impedes the movement of the dislocations that make pure iron ductile, and thus controls and enhances its qualities. These qualities include the hardness, quenching behaviour, need for annealing, tempering behaviour, yield strength, and tensile strength of the resulting steel. The increase in steel's strength compared to pure iron is possible only by reducing iron's ductility.
Steel:
Steel was produced in bloomery furnaces for thousands of years, but its large-scale, industrial use began only after more efficient production methods were devised in the 17th century, with the introduction of the blast furnace and production of crucible steel. This was followed by the open-hearth furnace and then the Bessemer process in England in the mid-19th century. With the invention of the Bessemer process, a new era of mass-produced steel began. Mild steel replaced wrought iron. The German states saw major steel prowess over Europe in the 19th century.Further refinements in the process, such as basic oxygen steelmaking (BOS), largely replaced earlier methods by further lowering the cost of production and increasing the quality of the final product. Today, steel is one of the most commonly manufactured materials in the world, with more than 1.6 billion tons produced annually. Modern steel is generally identified by various grades defined by assorted standards organisations. The modern steel industry is one of the largest manufacturing industries in the world, but also one of the most energy and greenhouse gas emission intense industries, contributing 8% of global emissions. However, steel is also very reusable: it is one of the world's most-recycled materials, with a recycling rate of over 60% globally.
Definitions and related materials:
The noun steel originates from the Proto-Germanic adjective stahliją or stakhlijan 'made of steel', which is related to stahlaz or stahliją 'standing firm'.The carbon content of steel is between 0.002% and 2.14% by weight for plain carbon steel (iron-carbon alloys). Too little carbon content leaves (pure) iron quite soft, ductile, and weak. Carbon contents higher than those of steel make a brittle alloy commonly called pig iron. Alloy steel is steel to which other alloying elements have been intentionally added to modify the characteristics of steel. Common alloying elements include: manganese, nickel, chromium, molybdenum, boron, titanium, vanadium, tungsten, cobalt, and niobium. Additional elements, most frequently considered undesirable, are also important in steel: phosphorus, sulfur, silicon, and traces of oxygen, nitrogen, and copper.
Definitions and related materials:
Plain carbon-iron alloys with a higher than 2.1% carbon content are known as cast iron. With modern steelmaking techniques such as powder metal forming, it is possible to make very high-carbon (and other alloy material) steels, but such are not common. Cast iron is not malleable even when hot, but it can be formed by casting as it has a lower melting point than steel and good castability properties. Certain compositions of cast iron, while retaining the economies of melting and casting, can be heat treated after casting to make malleable iron or ductile iron objects. Steel is distinguishable from wrought iron (now largely obsolete), which may contain a small amount of carbon but large amounts of slag.
Material properties:
Origins and production Iron is commonly found in the Earth's crust in the form of an ore, usually an iron oxide, such as magnetite or hematite. Iron is extracted from iron ore by removing the oxygen through its combination with a preferred chemical partner such as carbon which is then lost to the atmosphere as carbon dioxide. This process, known as smelting, was first applied to metals with lower melting points, such as tin, which melts at about 250 °C (482 °F), and copper, which melts at about 1,100 °C (2,010 °F), and the combination, bronze, which has a melting point lower than 1,083 °C (1,981 °F). In comparison, cast iron melts at about 1,375 °C (2,507 °F). Small quantities of iron were smelted in ancient times, in the solid-state, by heating the ore in a charcoal fire and then welding the clumps together with a hammer and in the process squeezing out the impurities. With care, the carbon content could be controlled by moving it around in the fire. Unlike copper and tin, liquid or solid iron dissolves carbon quite readily.
Material properties:
All of these temperatures could be reached with ancient methods used since the Bronze Age. Since the oxidation rate of iron increases rapidly beyond 800 °C (1,470 °F), it is important that smelting take place in a low-oxygen environment. Smelting, using carbon to reduce iron oxides, results in an alloy (pig iron) that retains too much carbon to be called steel. The excess carbon and other impurities are removed in a subsequent step.
Material properties:
Other materials are often added to the iron/carbon mixture to produce steel with the desired properties. Nickel and manganese in steel add to its tensile strength and make the austenite form of the iron-carbon solution more stable, chromium increases hardness and melting temperature, and vanadium also increases hardness while making it less prone to metal fatigue.To inhibit corrosion, at least 11% chromium can be added to steel so that a hard oxide forms on the metal surface; this is known as stainless steel. Tungsten slows the formation of cementite, keeping carbon in the iron matrix and allowing martensite to preferentially form at slower quench rates, resulting in high-speed steel. The addition of lead and sulfur decrease grain size, thereby making the steel easier to turn, but also more brittle and prone to corrosion. Such alloys are nevertheless frequently used for components such as nuts, bolts, and washers in applications where toughness and corrosion resistance are not paramount. For the most part, however, p-block elements such as sulfur, nitrogen, phosphorus, and lead are considered contaminants that make steel more brittle and are therefore removed from steel during the melting processing.
Material properties:
Properties The density of steel varies based on the alloying constituents but usually ranges between 7,750 and 8,050 kg/m3 (484 and 503 lb/cu ft), or 7.75 and 8.05 g/cm3 (4.48 and 4.65 oz/cu in).Even in a narrow range of concentrations of mixtures of carbon and iron that make steel, several different metallurgical structures, with very different properties can form. Understanding such properties is essential to making quality steel. At room temperature, the most stable form of pure iron is the body-centred cubic (BCC) structure called alpha iron or α-iron. It is a fairly soft metal that can dissolve only a small concentration of carbon, no more than 0.005% at 0 °C (32 °F) and 0.021 wt% at 723 °C (1,333 °F). The inclusion of carbon in alpha iron is called ferrite. At 910 °C, pure iron transforms into a face-centred cubic (FCC) structure, called gamma iron or γ-iron. The inclusion of carbon in gamma iron is called austenite. The more open FCC structure of austenite can dissolve considerably more carbon, as much as 2.1%, (38 times that of ferrite) carbon at 1,148 °C (2,098 °F), which reflects the upper carbon content of steel, beyond which is cast iron. When carbon moves out of solution with iron, it forms a very hard, but brittle material called cementite (Fe3C).
Material properties:
When steels with exactly 0.8% carbon (known as a eutectoid steel), are cooled, the austenitic phase (FCC) of the mixture attempts to revert to the ferrite phase (BCC). The carbon no longer fits within the FCC austenite structure, resulting in an excess of carbon. One way for carbon to leave the austenite is for it to precipitate out of solution as cementite, leaving behind a surrounding phase of BCC iron called ferrite with a small percentage of carbon in solution. The two, ferrite and cementite, precipitate simultaneously producing a layered structure called pearlite, named for its resemblance to mother of pearl. In a hypereutectoid composition (greater than 0.8% carbon), the carbon will first precipitate out as large inclusions of cementite at the austenite grain boundaries until the percentage of carbon in the grains has decreased to the eutectoid composition (0.8% carbon), at which point the pearlite structure forms. For steels that have less than 0.8% carbon (hypoeutectoid), ferrite will first form within the grains until the remaining composition rises to 0.8% of carbon, at which point the pearlite structure will form. No large inclusions of cementite will form at the boundaries in hypoeuctoid steel. The above assumes that the cooling process is very slow, allowing enough time for the carbon to migrate.
Material properties:
As the rate of cooling is increased the carbon will have less time to migrate to form carbide at the grain boundaries but will have increasingly large amounts of pearlite of a finer and finer structure within the grains; hence the carbide is more widely dispersed and acts to prevent slip of defects within those grains, resulting in hardening of the steel. At the very high cooling rates produced by quenching, the carbon has no time to migrate but is locked within the face-centred austenite and forms martensite. Martensite is a highly strained and stressed, supersaturated form of carbon and iron and is exceedingly hard but brittle. Depending on the carbon content, the martensitic phase takes different forms. Below 0.2% carbon, it takes on a ferrite BCC crystal form, but at higher carbon content it takes a body-centred tetragonal (BCT) structure. There is no thermal activation energy for the transformation from austenite to martensite. There is no compositional change so the atoms generally retain their same neighbors.Martensite has a lower density (it expands during the cooling) than does austenite, so that the transformation between them results in a change of volume. In this case, expansion occurs. Internal stresses from this expansion generally take the form of compression on the crystals of martensite and tension on the remaining ferrite, with a fair amount of shear on both constituents. If quenching is done improperly, the internal stresses can cause a part to shatter as it cools. At the very least, they cause internal work hardening and other microscopic imperfections. It is common for quench cracks to form when steel is water quenched, although they may not always be visible.
Material properties:
Heat treatment There are many types of heat treating processes available to steel. The most common are annealing, quenching, and tempering.
Material properties:
Annealing is the process of heating the steel to a sufficiently high temperature to relieve local internal stresses. It does not create a general softening of the product but only locally relieves strains and stresses locked up within the material. Annealing goes through three phases: recovery, recrystallization, and grain growth. The temperature required to anneal a particular steel depends on the type of annealing to be achieved and the alloying constituents.Quenching involves heating the steel to create the austenite phase then quenching it in water or oil. This rapid cooling results in a hard but brittle martensitic structure. The steel is then tempered, which is just a specialized type of annealing, to reduce brittleness. In this application the annealing (tempering) process transforms some of the martensite into cementite, or spheroidite and hence it reduces the internal stresses and defects. The result is a more ductile and fracture-resistant steel.
Production:
When iron is smelted from its ore, it contains more carbon than is desirable. To become steel, it must be reprocessed to reduce the carbon to the correct amount, at which point other elements can be added. In the past, steel facilities would cast the raw steel product into ingots which would be stored until use in further refinement processes that resulted in the finished product. In modern facilities, the initial product is close to the final composition and is continuously cast into long slabs, cut and shaped into bars and extrusions and heat treated to produce a final product. Today, approximately 96% of steel is continuously cast, while only 4% is produced as ingots.The ingots are then heated in a soaking pit and hot rolled into slabs, billets, or blooms. Slabs are hot or cold rolled into sheet metal or plates. Billets are hot or cold rolled into bars, rods, and wire. Blooms are hot or cold rolled into structural steel, such as I-beams and rails. In modern steel mills these processes often occur in one assembly line, with ore coming in and finished steel products coming out. Sometimes after a steel's final rolling, it is heat treated for strength; however, this is relatively rare.
History:
Ancient Steel was known in antiquity and was produced in bloomeries and crucibles.The earliest known production of steel is seen in pieces of ironware excavated from an archaeological site in Anatolia (Kaman-Kalehöyük) and are nearly 4,000 years old, dating from 1800 BC. Horace identifies steel weapons such as the falcata in the Iberian Peninsula, while Noric steel was used by the Roman military.The reputation of Seric iron of India (wootz steel) grew considerably in the rest of the world. Metal production sites in Sri Lanka employed wind furnaces driven by the monsoon winds, capable of producing high-carbon steel. Large-scale Wootz steel production in India using crucibles occurred by the sixth century BC, the pioneering precursor to modern steel production and metallurgy.The Chinese of the Warring States period (403–221 BC) had quench-hardened steel, while Chinese of the Han dynasty (202 BC—AD 220) created steel by melting together wrought iron with cast iron, thus producing a carbon-intermediate steel by the 1st century AD.There is evidence that carbon steel was made in Western Tanzania by the ancestors of the Haya people as early as 2,000 years ago by a complex process of "pre-heating" allowing temperatures inside a furnace to reach 1300 to 1400 °C.
History:
Wootz and Damascus Evidence of the earliest production of high carbon steel in India is found in Kodumanal in Tamil Nadu, the Golconda area in Andhra Pradesh and Karnataka, and in the Samanalawewa, Dehigaha Alakanda, areas of Sri Lanka. This came to be known as Wootz steel, produced in South India by about the sixth century BC and exported globally. The steel technology existed prior to 326 BC in the region as they are mentioned in literature of Sangam Tamil, Arabic, and Latin as the finest steel in the world exported to the Romans, Egyptian, Chinese and Arab worlds at that time – what they called Seric Iron. A 200 BC Tamil trade guild in Tissamaharama, in the South East of Sri Lanka, brought with them some of the oldest iron and steel artifacts and production processes to the island from the classical period. The Chinese and locals in Anuradhapura, Sri Lanka had also adopted the production methods of creating Wootz steel from the Chera Dynasty Tamils of South India by the 5th century AD. In Sri Lanka, this early steel-making method employed a unique wind furnace, driven by the monsoon winds, capable of producing high-carbon steel. Since the technology was acquired from the Tamilians from South India, the origin of steel technology in India can be conservatively estimated at 400–500 BC.The manufacture of what came to be called Wootz, or Damascus steel, famous for its durability and ability to hold an edge, may have been taken by the Arabs from Persia, who took it from India. It was originally created from several different materials including various trace elements, apparently ultimately from the writings of Zosimos of Panopolis. In 327 BC, Alexander the Great was rewarded by the defeated King Porus, not with gold or silver but with 30 pounds of steel. A recent study has speculated that carbon nanotubes were included in its structure, which might explain some of its legendary qualities, though, given the technology of that time, such qualities were produced by chance rather than by design. Natural wind was used where the soil containing iron was heated by the use of wood. The ancient Sinhalese managed to extract a ton of steel for every 2 tons of soil, a remarkable feat at the time. One such furnace was found in Samanalawewa and archaeologists were able to produce steel as the ancients did.Crucible steel, formed by slowly heating and cooling pure iron and carbon (typically in the form of charcoal) in a crucible, was produced in Merv by the 9th to 10th century AD. In the 11th century, there is evidence of the production of steel in Song China using two techniques: a "berganesque" method that produced inferior, inhomogeneous steel, and a precursor to the modern Bessemer process that used partial decarburization via repeated forging under a cold blast.
History:
Modern Since the 17th century, the first step in European steel production has been the smelting of iron ore into pig iron in a blast furnace. Originally employing charcoal, modern methods use coke, which has proven more economical.
History:
Processes starting from bar iron In these processes, pig iron was refined (fined) in a finery forge to produce bar iron, which was then used in steel-making.The production of steel by the cementation process was described in a treatise published in Prague in 1574 and was in use in Nuremberg from 1601. A similar process for case hardening armor and files was described in a book published in Naples in 1589. The process was introduced to England in about 1614 and used to produce such steel by Sir Basil Brooke at Coalbrookdale during the 1610s.The raw material for this process were bars of iron. During the 17th century, it was realized that the best steel came from oregrounds iron of a region north of Stockholm, Sweden. This was still the usual raw material source in the 19th century, almost as long as the process was used.Crucible steel is steel that has been melted in a crucible rather than having been forged, with the result that it is more homogeneous. Most previous furnaces could not reach high enough temperatures to melt the steel. The early modern crucible steel industry resulted from the invention of Benjamin Huntsman in the 1740s. Blister steel (made as above) was melted in a crucible or in a furnace, and cast (usually) into ingots.
History:
Processes starting from pig iron The modern era in steelmaking began with the introduction of Henry Bessemer's process in 1855, the raw material for which was pig iron. His method let him produce steel in large quantities cheaply, thus mild steel came to be used for most purposes for which wrought iron was formerly used. The Gilchrist-Thomas process (or basic Bessemer process) was an improvement to the Bessemer process, made by lining the converter with a basic material to remove phosphorus.
History:
Another 19th-century steelmaking process was the Siemens-Martin process, which complemented the Bessemer process. It consisted of co-melting bar iron (or steel scrap) with pig iron.
History:
These methods of steel production were rendered obsolete by the Linz-Donawitz process of basic oxygen steelmaking (BOS), developed in 1952, and other oxygen steel making methods. Basic oxygen steelmaking is superior to previous steelmaking methods because the oxygen pumped into the furnace limited impurities, primarily nitrogen, that previously had entered from the air used, and because, with respect to the open hearth process, the same quantity of steel from a BOS process is manufactured in one-twelfth the time. Today, electric arc furnaces (EAF) are a common method of reprocessing scrap metal to create new steel. They can also be used for converting pig iron to steel, but they use a lot of electrical energy (about 440 kWh per metric ton), and are thus generally only economical when there is a plentiful supply of cheap electricity.
Industry:
The steel industry is often considered an indicator of economic progress, because of the critical role played by steel in infrastructural and overall economic development. In 1980, there were more than 500,000 U.S. steelworkers. By 2000, the number of steelworkers had fallen to 224,000.The economic boom in China and India caused a massive increase in the demand for steel. Between 2000 and 2005, world steel demand increased by 6%. Since 2000, several Indian and Chinese steel firms have risen to prominence, such as Tata Steel (which bought Corus Group in 2007), Baosteel Group and Shagang Group. As of 2017, though, ArcelorMittal is the world's largest steel producer. In 2005, the British Geological Survey stated China was the top steel producer with about one-third of the world share; Japan, Russia, and the US followed respectively. The large production capacity of steel results also in a significant amount of carbon dioxide emissions inherent related to the main production route. In 2021, it was estimated that around 7% of the global greenhouse gas emissions resulted from the steel industry. Reduction of these emissions are expected to come from a shift in the main production route using cokes, more recycling of steel and the application of carbon capture and storage or carbon capture and utilization technology.
Industry:
In 2008, steel began trading as a commodity on the London Metal Exchange. At the end of 2008, the steel industry faced a sharp downturn that led to many cut-backs.
Recycling:
Steel is one of the world's most-recycled materials, with a recycling rate of over 60% globally; in the United States alone, over 82,000,000 metric tons (81,000,000 long tons; 90,000,000 short tons) were recycled in the year 2008, for an overall recycling rate of 83%.As more steel is produced than is scrapped, the amount of recycled raw materials is about 40% of the total of steel produced - in 2016, 1,628,000,000 tonnes (1.602×109 long tons; 1.795×109 short tons) of crude steel was produced globally, with 630,000,000 tonnes (620,000,000 long tons; 690,000,000 short tons) recycled.
Contemporary:
Carbon Modern steels are made with varying combinations of alloy metals to fulfill many purposes. Carbon steel, composed simply of iron and carbon, accounts for 90% of steel production. Low alloy steel is alloyed with other elements, usually molybdenum, manganese, chromium, or nickel, in amounts of up to 10% by weight to improve the hardenability of thick sections. High strength low alloy steel has small additions (usually < 2% by weight) of other elements, typically 1.5% manganese, to provide additional strength for a modest price increase.Recent Corporate Average Fuel Economy (CAFE) regulations have given rise to a new variety of steel known as Advanced High Strength Steel (AHSS). This material is both strong and ductile so that vehicle structures can maintain their current safety levels while using less material. There are several commercially available grades of AHSS, such as dual-phase steel, which is heat treated to contain both a ferritic and martensitic microstructure to produce a formable, high strength steel. Transformation Induced Plasticity (TRIP) steel involves special alloying and heat treatments to stabilize amounts of austenite at room temperature in normally austenite-free low-alloy ferritic steels. By applying strain, the austenite undergoes a phase transition to martensite without the addition of heat. Twinning Induced Plasticity (TWIP) steel uses a specific type of strain to increase the effectiveness of work hardening on the alloy.Carbon Steels are often galvanized, through hot-dip or electroplating in zinc for protection against rust.
Contemporary:
Alloy Stainless steels contain a minimum of 11% chromium, often combined with nickel, to resist corrosion. Some stainless steels, such as the ferritic stainless steels are magnetic, while others, such as the austenitic, are nonmagnetic. Corrosion-resistant steels are abbreviated as CRES.
Contemporary:
Alloy steels are plain-carbon steels in which small amounts of alloying elements like chromium and vanadium have been added. Some more modern steels include tool steels, which are alloyed with large amounts of tungsten and cobalt or other elements to maximize solution hardening. This also allows the use of precipitation hardening and improves the alloy's temperature resistance. Tool steel is generally used in axes, drills, and other devices that need a sharp, long-lasting cutting edge. Other special-purpose alloys include weathering steels such as Cor-ten, which weather by acquiring a stable, rusted surface, and so can be used un-painted. Maraging steel is alloyed with nickel and other elements, but unlike most steel contains little carbon (0.01%). This creates a very strong but still malleable steel.Eglin steel uses a combination of over a dozen different elements in varying amounts to create a relatively low-cost steel for use in bunker buster weapons. Hadfield steel (after Sir Robert Hadfield) or manganese steel contains 12–14% manganese which when abraded strain-hardens to form a very hard skin which resists wearing. Examples include tank tracks, bulldozer blade edges, and cutting blades on the jaws of life.
Contemporary:
Standards Most of the more commonly used steel alloys are categorized into various grades by standards organizations. For example, the Society of Automotive Engineers has a series of grades defining many types of steel. The American Society for Testing and Materials has a separate set of standards, which define alloys such as A36 steel, the most commonly used structural steel in the United States. The JIS also defines a series of steel grades that are being used extensively in Japan as well as in developing countries.
Uses:
Iron and steel are used widely in the construction of roads, railways, other infrastructure, appliances, and buildings. Most large modern structures, such as stadiums and skyscrapers, bridges, and airports, are supported by a steel skeleton. Even those with a concrete structure employ steel for reinforcing. It sees widespread use in major appliances and cars. Despite the growth in usage of aluminium, steel is still the main material for car bodies. Steel is used in a variety of other construction materials, such as bolts, nails and screws and other household products and cooking utensils.Other common applications include shipbuilding, pipelines, mining, offshore construction, aerospace, white goods (e.g. washing machines), heavy equipment such as bulldozers, office furniture, steel wool, tool, and armour in the form of personal vests or vehicle armour (better known as rolled homogeneous armour in this role).
Uses:
Historical Before the introduction of the Bessemer process and other modern production techniques, steel was expensive and was only used where no cheaper alternative existed, particularly for the cutting edge of knives, razors, swords, and other items where a hard, sharp edge was needed. It was also used for springs, including those used in clocks and watches.With the advent of speedier and thriftier production methods, steel has become easier to obtain and much cheaper. It has replaced wrought iron for a multitude of purposes. However, the availability of plastics in the latter part of the 20th century allowed these materials to replace steel in some applications due to their lower fabrication cost and weight. Carbon fiber is replacing steel in some cost insensitive applications such as sports equipment and high-end automobiles.
Uses:
Long As reinforcing bars and mesh in reinforced concrete Railroad tracks Structural steel in modern buildings and bridges Wires Input to reforging applications Flat carbon Major appliances Magnetic cores The inside and outside body of automobiles, trains, and ships.
Weathering (COR-TEN) Intermodal containers Outdoor sculptures Architecture Highliner train cars Stainless Low-background Steel manufactured after World War II became contaminated with radionuclides by nuclear weapons testing. Low-background steel, steel manufactured prior to 1945, is used for certain radiation-sensitive applications such as Geiger counters and radiation shielding. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Dirichlet's test**
Dirichlet's test:
In mathematics, Dirichlet's test is a method of testing for the convergence of a series. It is named after its author Peter Gustav Lejeune Dirichlet, and was published posthumously in the Journal de Mathématiques Pures et Appliquées in 1862.
Statement:
The test states that if (an) is a sequence of real numbers and (bn) a sequence of complex numbers satisfying (an) is monotonic lim n→∞an=0 |∑n=1Nbn|≤M for every positive integer Nwhere M is some constant, then the series converges.
Proof:
Let {\textstyle S_{n}=\sum _{k=1}^{n}a_{k}b_{k}} and {\textstyle B_{n}=\sum _{k=1}^{n}b_{k}} From summation by parts, we have that {\textstyle S_{n}=a_{n}B_{n}+\sum _{k=1}^{n-1}B_{k}(a_{k}-a_{k+1})} . Since Bn is bounded by M and an→0 , the first of these terms approaches zero, anBn→0 as n→∞ We have, for each k, |Bk(ak−ak+1)|≤M|ak−ak+1| Since (an) is monotone, it is either decreasing or increasing: If (an) is decreasing, which is a telescoping sum that equals M(a1−an+1) and therefore approaches Ma1 as n→∞ . Thus, {\textstyle \sum _{k=1}^{\infty }M(a_{k}-a_{k+1})} converges.
Proof:
If (an) is increasing, which is again a telescoping sum that equals −M(a1−an+1) and therefore approaches −Ma1 as n→∞ . Thus, again, {\textstyle \sum _{k=1}^{\infty }M(a_{k}-a_{k+1})} converges.
So, the series {\textstyle \sum _{k=1}^{\infty }B_{k}(a_{k}-a_{k+1})} converges, by the absolute convergence test. Hence Sn converges.
Applications:
A particular case of Dirichlet's test is the more commonly used alternating series test for the case Another corollary is that sin {\textstyle \sum _{n=1}^{\infty }a_{n}\sin n} converges whenever (an) is a decreasing sequence that tends to zero. To see that sin n is bounded, we can use the summation formula
Improper integrals:
An analogous statement for convergence of improper integrals is proven using integration by parts. If the integral of a function f is uniformly bounded over all intervals, and g is a non-negative monotonically decreasing function, then the integral of fg is a convergent improper integral. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Chinese wax**
Chinese wax:
Chinese wax is a white to yellowish-white, gelatinous, crystalline water-insoluble substance obtained from the wax secreted by certain insects.
Chinese wax:
It resembles spermaceti but is harder, more friable, and with a higher melting point. Two scale insects produce the wax: Ceroplastes ceriferus, common in China and India, and the related Ericerus pela, found in China and Japan. These insects deposit their secretions on the branches of certain species of Ligustrum (privet) tree. The insects and their secretions are harvested and boiled with water to extract the raw wax. The insect bodies, which settle to the bottom, are used as food for swine.According to an article in a November 1932 magazine article in the journal Nature by Herbert Beardsley, "...the male larvae of a white insect, about the size of a mosquito, built a cocoon of pure, shining wax. The tree that produces the white wax insect grows in the Chien-Chang Valley, and there, about march, one may see, on the limbs and branches, round, brown forms, which contain innumerable white insects. If they are allowed to remain where they are, they will eventually drop off in a dead mass, for the food is not right for them; but if they are transported to other kinds of plants, the females will lay their eggs, the larvae will thrive and the male larvae will construct their shining palaces, which yield a profit to the wax-farmers. So, late in March, the insects are tied up in a leaf of the wood oil tree, then placed in gourd like receptacles which are packed into two large bamboo baskets. Runners or porters lift the baskets on their shoulders, and, traveling entirely at night – for to submit the insects to the midday heat would cause the pupal stage to end too soon – traverse the rocky paths and lofty ascents of the Cze-Chuan Mountains to arrive finally at the farming districts. The baskets of insects are distributed to the farmers, who proceed at once to place the creatures upon the food plant, which is generally a species of flowering ash about five or six feet high. They are tied to the branches in small bags made of leaves, and holes are punched in the bags with a blunt needle so the adults may find their way out. When first emerging, the insects creep rapidly up to the leaves of the food plant, where they nestle for nearly two weeks. After this they begin to scatter and crawl along the branches. About the first of June, the females begin to lay their eggs, and the wax cocoons are formed in August in time completely coating every branch and stem. By the first of September the whole tree is literally covered with layers of pure white wax a quarter of an inch thick. The farmers then scrape the branches, and prepare the wax of the market."
Uses:
Chinese wax is used chiefly in the manufacture of sizes, candles, temple images and other articles connected with ceremonial worship, and polish for furniture. It is also used for burnishing the back of Chinese hanging scrolls with a stone.In China the wax has been employed medicinally. Taken internally, it has been used as a remedy for hoarseness, pain, worms, nervousness, and to aid the mending of broken bones. Externally, it has been used as an ointment for treatment of wounds.
Other names:
Other names for Chinese wax include: Chinese tree wax Chinese insect wax Insect wax White waxIn Japan the tree yielding it is called ibota and the wax ibotaro. Among other uses, it is used to polish white clamshell go stones. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Valve RF amplifier**
Valve RF amplifier:
A valve RF amplifier (UK and Aus.) or tube amplifier (U.S.) is a device for electrically amplifying the power of an electrical radio frequency signal.
Low to medium power valve amplifiers for frequencies below the microwaves were largely replaced by solid state amplifiers during the 1960s and 1970s, initially for receivers and low power stages of transmitters, transmitter output stages switching to transistors somewhat later. Specially constructed valves are still in use for very high power transmitters, although rarely in new designs.
Valve characteristics:
Valves are high voltage / low current devices in comparison with transistors. Tetrode and pentode valves have very flat anode current vs. anode voltage indicating high anode output impedances. Triodes show a stronger relationship between anode voltage and anode current.
Valve characteristics:
The high working voltage makes them well suited for radio transmitters and valves remain in use today for very high power short wave radio transmitters, where solid state techniques would require many devices in parallel, and very high DC supply currents. High power solid state transmitters also require a complex combination of transformers and tuning networks, whereas a valve-based transmitter would use a single, relatively simple tuned network.
Valve characteristics:
Thus while solid state high power short wave transmitters are technically possible, economic considerations still favor valves above 3 MHz and 10,000 watts.
Radio amateurs also use valve amplifiers in the 500–1500 watt range mainly for economic reasons.
Valve characteristics:
Audio vs. RF amplifiers Valve audio amplifiers typically amplify the entire audio range between 20 Hz and 20 kHz or higher. They use an iron core transformer to provide a suitable high impedance load to the valve(s) while driving a speaker, which is typically 8 Ohms. Audio amplifiers normally use a single valve in class A, or a pair in class B or class AB.
Valve characteristics:
An RF power amplifier is tuned to a single frequency as low as 18 kHz and as high as the UHF range of frequencies, for the purpose of radio transmission or industrial heating. They use a narrow tuned circuit to provide the valve with a suitably high load impedance and feed a load that is typically 50 or 75 Ohms. RF amplifiers normally operate class C or class AB.
Valve characteristics:
Although the frequency ranges for audio amplifiers and RF amplifiers overlap, the class of operation, method of output coupling and percent operational bandwidth will differ. Power valves are capable of high frequency response, up to at least 30 MHz. Indeed, many of the Directly Heated Single Ended Triode (DH-SET) audio amplifiers use radio transmitting valves originally designed to operate as RF amplifiers in the high frequency range.
Valve characteristics:
Circuit advantages of valves High input impedance Tubes' input impedance is comparable to that of FET‑s, higher than in bipolar transistors, which is beneficial in certain signal amplification applications.
Tolerant of high voltages Valves are high voltage devices, inherently suitable for higher voltage circuits than most semiconductors.
Valve characteristics:
Tubes can be built oversized to improve cooling Valves can be constructed on a scale large enough to dissipate great amounts of heat. Very high-power models are designed to accommodate water- or vapor-cooling. For that reason, valves remained the only viable technology for handling very high power, and especially high power + high voltage use, such as radio and TV transmitters, long into the age when transistors had displaced valves in almost all other applications. However, today even for high power/voltage, tubes are increasingly becoming obsolete as new transistor technology improves tolerance of high voltages and capacity for high power.
Valve characteristics:
Lower investment cost Because of the simplicity of practical tube-based designs, using tubes for applications like RF amplifiers above the kilowatt power range can greatly lower manufacturing costs. Also, large, high value power valves (steel clad, not glass tubes) can to some extent be remanufactured to extend residual life.
Electrically very robust Tubes can tolerate amazingly high overloads, which would destroy bipolar transistor systems in milliseconds (of particular significance in military and other "strategically important" systems).
Indefinite shelf life Even 60 year-old tubes can be perfectly functional, and many types are available for purchase as "new-old-stock". Thus, despite known reliability issues (see next section, below), it is still perfectly possible to run most very old vacuum tube equipment.
Valve characteristics:
Comparative ease of replacement Being known to be subject to a number of common failure modes, most systems with tubes were designed with sockets so the tubes can be installed as plug-in devices; they are rarely, if ever, soldered into a circuit. A failed tube can simply be unplugged and replaced by a user, while the failure of a soldered-in semiconductor may constitute damage beyond economical repair for a whole product or sub-assembly. The only difficulty is determining which tube has failed.
Valve characteristics:
Disadvantages of valves Cost For most applications, tubes require both greater initial outlay and running expense per amplification stage, requiring more attentive budgeting of the number of stages for a given application compared to semiconductors.Short operational life In the most common applications, valves have a working life of just a few thousand hours, much shorter than solid state parts. This is due various commonplace modes of failure: Cathode depletion, open- or short-circuits (notably of the heater and grid structures), cathode ‘poisoning’, and breaking the glass shell (the glass “tube” itself). Heater failure most often happens due to the mechanical stress of a cold start. Only in certain limited, always-on professional applications, such as specialized computing and undersea cables, have specially designed valves in carefully designed circuits, and well cooled environments reached operational lives of tens or hundreds of thousands of hours.Heater supplies are required for the cathodes Beside the investment cost, the share of the power budget that goes into heating the cathode, without contributing to output, can range from few percent points of anode dissipation (in high power applications at full output), to broadly comparable to anode dissipation in small signal applications.Large circuit temperature swings in on/off cycles Massive stray heat from cathode heaters in common low power tubes means that adjoining circuits experience changes in temperature that can exceed 100 °C (212 °F). This requires heat resistant components. In RF applications this also means that all frequency-determining components may have to heat to thermal equilibrium before frequency stability is reached. While at AM broadcast (medium wave) receivers and in loosely tuned TV sets this was not a problem, in typical radio receivers and transmitters with free-running oscillators at HF frequencies this thermal stabilization required about one hour. On the other hand, miniature ultra-low power direct-heated valves do not produce much heat in absolute terms, cause more modest temperature swings, and allow equipment that contains few of them to stabilize sooner.No "instant on" from a cold start Valve cathodes need to heat to a glow to start conducting. In indirect-heating cathodes this could take up to 20 seconds. Apart from temperature-related instability, this meant that valves would not work instantly when powered. This led to development of always-on preheating systems for vacuum tube appliances that shortened the wait and may have reduced valve failures from thermal shock, but at the price of a continuous power drain, and an increased fire hazard. On the other hand, very small, ultra low power direct-heated valves turn on in tenths of a second from a cold start.Dangerously high voltages Anodes of tubes may require dangerously high voltages to function as intended. In general, tubes themselves will not be troubled by high voltage, but high voltages will demand extra precautions in circuit layout and design, to avoid “flashover”.Wrong impedance for convenient use High impedance output (high voltage/low current) is typically not suitable for directly driving many real world loads, notably various forms of electric motorValves only have one polarity Compared to transistors, valves have the disadvantage of having a single polarity, whereas for most uses, transistors are available as pairs with complementary polarities (e.g., NPN / PNP), making possible many circuit configurations that cannot be realized with valves.
Valve characteristics:
Distortion The most efficient valve-based RF amplifiers operate class C. If used with no tuned circuit in the output, this would distort the input signal, producing harmonics. However, class C amplifiers normally use a high Q output network which removes the harmonics, leaving an undistorted sine wave identical to the input waveform. Class C is suitable only for amplifying signals with a constant amplitude, such as FM, FSK, and some CQ (Morse code) signals. Where the amplitude of the input signal to the amplifier varies as with single-sideband modulation, amplitude modulation, video and complex digital signals, the amplifier must operate class A or AB, to preserve the envelope of the driving signal in an undistorted form. Such amplifiers are referred to as linear amplifiers.
Valve characteristics:
It is also common to modify the gain of an amplifier operating class C so as to produce amplitude modulation. If done in a linear manner, this modulated amplifier is capable of low distortion. The output signal can be viewed as a product of the input RF signal and the modulating signal.
Valve characteristics:
The development of FM broadcasting improved fidelity by using a greater bandwidth which was available in the VHF range, and where atmospheric noise was absent. FM also has an inherent ability to reject noise, which is mostly amplitude modulated. Valve technology suffers high-frequency limitations due to cathode-anode transit time. However, tetrodes are successfully used into the VHF range and triodes into the low GHz range. Modern FM broadcast transmitters use both valve and solid state devices, with valves tending to be more used at the highest power levels. FM transmitters operate class C with very low distortion.
Valve characteristics:
Today's digital radio that carries coded data over various phase modulations (such as GMSK, QPSK, etc.) and also the increasing demand for spectrum have forced a dramatic change in the way radio is used, e.g. the cellular radio concept. Today's cellular radio and digital broadcast standards are extremely demanding in terms of the spectral envelope and out of band emissions that are acceptable (in the case of GSM for example, −70 dB or better just a few hundred kilohertz from center frequency). Digital transmitters must therefore operate in the linear modes, with much attention given to achieving low distortion.
Applications:
Historic transmitters and receivers (High voltage/high power) Valve stages were used to amplify the received radio frequency signals, the intermediate frequencies, the video signal and the audio signals at the various points in the receiver. Historically (pre WWII) "transmitting tubes" were among the most powerful tubes available, were usually direct heated by thoriated filaments that glowed like light bulbs. Some tubes were built to be very rugged, capable of being driven so hard that the anode would itself glow cherry red, the anodes being machined from solid material (rather than fabricated from thin sheet) to be able to withstand this without distorting when heated. Notable tubes of this type are the 845 and 211. Later beam power tubes such as the 807 and (direct heated) 813 were also used in large numbers in (especially military) radio transmitters.
Applications:
Bandwidth of valve vs solid state amplifiers Today, radio transmitters are overwhelmingly solid state, even at microwave frequencies (cellular radio base stations). Depending on the application, a fair number of radio frequency amplifiers continue to have valve construction, due to their simplicity, where as, it takes several output transistors with complex splitting and combining circuits to equal the same amount of output power of a single valve.
Applications:
Valve amplifier circuits are significantly different from broadband solid state circuits. Solid state devices have a very low output impedance which allows matching via a broadband transformer covering a large range of frequencies, for example 1.8 to 30 MHz. With either class C or AB operation, these must include low pass filters to remove harmonics. While the proper low pass filter must be switch selected for the frequency range of interest, the result is considered to be a "no tune" design. Valve amplifiers have a tuned network that serves as both the low pass harmonic filter and impedance matching to the output load. In either case, both solid state and valve devices need such filtering networks before the RF signal is output to the load.
Radio circuits:
Unlike audio amplifiers, in which the analog output signal is of the same form and frequency as the input signal, RF circuits may modulate low frequency information (audio, video, or data) onto a carrier (at a much higher frequency), and the circuitry comprises several distinct stages. For example, a radio transmitter may contain: an audio frequency (AF) stage (typically using conventional broadband small signal circuitry as described in Valve audio amplifier, one or more oscillator stages that generate the carrier wave, one or more mixer stages that modulate the carrier signal from the oscillator, the amplifier stage itself operating at (typically) high frequency. the Transmitter power amp itself is the only high power stage in a radio system, and operates at the carrier frequency. In AM, the modulation (frequency mixing) usually takes place in the final amplifier itself.
Radio circuits:
Transmitter anode circuits The most common anode circuit is a tuned LC circuit where the anodes are connected at a voltage node. This circuit is often known as the anode tank circuit.
Active (or tuned grid) amplifier An example of this used at VHF/UHF include the 4CX250B, an example of a twin tetrode is the QQV06/40A.
Radio circuits:
Neutralization is a term used in TGTP (tuned grid tuned plate) amplifiers for the methods and circuits used for stabilization against unwanted oscillations at the operating frequency caused by the inadvertent introduction of some of the output signal back into the input circuits. This mainly occurs via the grid to plate capacity, but can also come via other paths, making circuit layout important. To cancel the unwanted feedback signal, a portion of the output signal is deliberately introduced into the input circuit with the same amplitude but opposite phase.
Radio circuits:
When using a tuned circuit in the input, the network must match the driving source to the input impedance of the grid. This impedance will be determined by the grid current in Class C or AB2 operation. In AB1 operation, the grid circuit should be designed to avoid excessive step up voltage, which although it might provide more stage gain, as in audio designs, it will increase instability and make neutralization more critical.
Radio circuits:
In common with all three basic designs shown here, the anode of the valve is connected to a resonant LC circuit which has another inductive link which allows the RF signal to be passed to the output.
The circuit shown has been largely replaced by a Pi network which allows simpler adjustment and adds low pass filtering.
Radio circuits:
Operation The anode current is controlled by the electrical potential (voltage) of the first grid. A DC bias is applied to the valve to ensure that the part of the transfer equation which is most suitable to the required application is used. The input signal is able to perturb (change) the potential of the grid, this in turn will change the anode current (also known as the plate current).
Radio circuits:
In the RF designs shown on this page, a tuned circuit is between the anode and the high voltage supply. This tuned circuit is brought to resonance presenting an inductive load that is well matched to the valve and thus results in an efficient power transfer.
As the current flowing through the anode connection is controlled by the grid, then the current flowing through the load is also controlled by the grid.
One of the disadvantages of a tuned grid compared to other RF designs is that neutralization is required.
Radio circuits:
Passive grid amplifier A passive grid circuit used at VHF/UHF frequencies might use the 4CX250B tetrode. An example of a twin tetrode would be the QQV06/40A. The tetrode has a screen grid which is between the anode and the first grid, which being grounded for RF, acts as a shield to reducing the effective capacitance between the first grid and the anode. The combination of the effects of the screen grid and the grid damping resistor often allow the use of this design without neutralization. The screen found in tetrodes and pentodes, greatly increases the valve's gain by reducing the effect of anode voltage on anode current.
Radio circuits:
The input signal is applied to the valve's first grid via a capacitor. The value of the grid resistor determines the gain of the amplifier stage. The higher the resistor the greater the gain, the lower the damping effect and the greater the risk of instability. With this type of stage good layout is less vital.
Radio circuits:
Advantages Stable, no neutralizing required normally Constant load on the exciting stage Disadvantages Low gain, more input power is required Less gain than tuned grid Less filtering than tuned grid (more broadband), hence the amplification of out of band spurious signals, such as harmonics, from an exciter is greater Grounded grid amplifier This design normally uses a triode so valves such as the 4CX250B are not suitable for this circuit, unless the screen and control grids are joined, effectively converting the tetrode into a triode. This circuit design has been used at 1296 MHz using disk seal triode valves such as the 2C39A.
Radio circuits:
The grid is grounded and the drive is applied to the cathode through a capacitor. The heater supply must be isolated from the cathode as unlike the other designs the cathode is not connected to RF ground. Some valves, such as the 811A, are designed for "zero bias" operation and the cathode can be at ground potential for DC. Valves that require a negative grid bias can be used by putting a positive DC voltage on the cathode. This can be achieved by putting a zener diode between the cathode and ground or using a separate bias supply.
Radio circuits:
Advantages Stable, no neutralizing required normally Some of the power from exciting stage appears in the output Disadvantages Relatively low gain, typically about 10 dB.
The heater must be isolated from ground with chokes.
Radio circuits:
Neutralization The valve interelectrode capacitance which exists between the input and output of the amplifier and other stray coupling may allow enough energy to feed back into input so as to cause self-oscillation in an amplifier stage. For the higher gain designs this effect must be counteracted. Various methods exist for introducing an out-of-phase signal from the output back to the input so that the effect is cancelled. Even when the feed back is not sufficient to cause oscillation it can produce other effects, such as difficult tuning. Therefore, neutralization can be helpful, even for an amplifier that does not oscillate. Many grounded grid amplifiers use no neutralization, but at 30 MHz adding it can smooth out the tuning.
Radio circuits:
An important part of the neutralization of a tetrode or pentode is the design of the screen grid circuit. To provide the greatest shielding effect, the screen must be well-grounded at the frequency of operation. Many valves will have a "self-neutralizing" frequency somewhere in the VHF range. This results from a series resonance consisting of the screen capacity and the inductance of the screen lead, thus providing a very low impedance path to ground.
Radio circuits:
UHF Transit time effects are important at these frequencies, so feedback is not normally usable and for performance critical applications alternative linearisation techniques have to be used such as degeneration and feedforward.
Tube noise and noise figure Noise figure is not usually an issue for power amplifier valves, however, in receivers using valves it can be important. While such uses are obsolete, this information is included for historical interest.
Radio circuits:
Like any amplifying device, valves add noise to the signal to be amplified. Even with a hypothetical perfect amplifier, however, noise is unavoidably present due to thermal fluctuations in the signal source (usually assumed to be at room temperature, T = 295 K). Such fluctuations cause an electrical noise power of kBTB , where kB is the Boltzmann constant and B the bandwidth. Correspondingly, the voltage noise of a resistance R into an open circuit is 4∗kB∗T∗B∗R)1/2 and the current noise into a short circuit is 4∗kB∗T∗B/R)1/2 The noise figure is defined as the ratio of the noise power at the output of the amplifier relative to the noise power that would be present at the output if the amplifier were noiseless (due to amplification of thermal noise of the signal source). An equivalent definition is: noise figure is the factor by which insertion of the amplifier degrades the signal to noise ratio. It is often expressed in decibels (dB). An amplifier with a 0 dB noise figure would be perfect.
Radio circuits:
The noise properties of tubes at audio frequencies can be modeled well by a perfect noiseless tube having a source of voltage noise in series with the grid. For the EF86 tube, for example, this voltage noise is specified (see e.g., the Valvo, Telefunken or Philips data sheets) as 2 microvolts integrated over a frequency range of approximately 25 Hz to 10 kHz. (This refers to the integrated noise, see below for the frequency dependence of the noise spectral density.) This equals the voltage noise of a 25 kΩ resistor. Thus, if the signal source has an impedance of 25 kΩ or more, the noise of the tube is actually smaller than the noise of the source. For a source of 25 kΩ, the noise generated by tube and source are the same, so the total noise power at the output of the amplifier is twice the noise power at the output of the perfect amplifier. The noise figure is then two, or 3 dB. For higher impedances, such as 250 kΩ, the EF86's voltage noise is 10 1/2 lower than the source's own noise. It therefore adds 1/10 of the noise power caused by the source, and the noise figure is 0.4 dB. For a low-impedance source of 250 Ω, on the other hand, the noise voltage contribution of the tube is 10 times larger than the signal source, so that the noise power is one hundred times larger than that caused by the source. The noise figure in this case is 20 dB.
Radio circuits:
To obtain low noise figure the impedance of the source can be increased by a transformer. This is eventually limited by the input capacity of the tube, which sets a limit on how high the signal impedance can be made if a certain bandwidth is desired.
Radio circuits:
The noise voltage density of a given tube is a function of frequency. At frequencies above 10 kHz or so, it is basically constant ("white noise"). White noise is often expressed by an equivalent noise resistance, which is defined as the resistance which produces the same voltage noise as present at the tube input. For triodes, it is approximately (2-4)/gm, where gm is the transconductivity. For pentodes, it is higher, about (5-7)/gm. Tubes with high gm thus tend to have lower noise at high frequencies. For example, it is 300 Ω for one half of the ECC88, 250 Ω for an E188CC (both have gm = 12.5 mA/V) and as low as 65 Ω for a tride-connected D3a (gm = 40 mA/V).
Radio circuits:
In the audio frequency range (below 1–100 kHz), "1/f" noise becomes dominant, which rises like 1/f. (This is the reason for the relatively high noise resistance of the EF86 in the above example.) Thus, tubes with low noise at high frequency do not necessarily have low noise in the audio frequency range. For special low-noise audio tubes, the frequency at which 1/f noise takes over is reduced as far as possible, maybe to approximately a kilohertz. It can be reduced by choosing very pure materials for the cathode nickel, and running the tube at an optimized (generally low) anode current.
Radio circuits:
At radio frequencies, things are more complicated: (i) The input impedance of a tube has a real component that goes down like 1/f² (due to cathode lead inductance and transit time effects). This means the input impedance can no longer be increased arbitrarily in order to reduce the noise figure. (ii) This input resistance has its own thermal noise, just like any resistor. (The "temperature" of this resistor for noise purposes is more close to the cathode temperature than to room temperature). Thus, the noise figure of tube amplifiers increases with frequency. At 200 MHz, a noise figure of 2.5 (or 4 dB) can be reached with the ECC2000 tube in an optimized "cascode"-circuit with an optimized source impedance. At 800 MHz, tubes like EC8010 have noise figures of about 10 dB or more. Planar triodes are better, but very early, transistors have reached noise figures substantially lower than tubes at UHF. Thus, the tuners of television sets were among the first parts of consumer electronics were transistors were used.
Decline:
Semiconductor amplifiers have overwhelmingly displaced valve amplifiers for low- and medium-power applications at all frequencies.
Valves continue to be used in some high-power, high-frequency amplifiers used for short wave broadcasting, VHF and UHF TV and (VHF) FM radio, also in existing "radar, countermeasures equipment, or communications equipment" using specially designed valves, such as the klystron, gyrotron, traveling-wave tube, and crossed-field amplifier; however, new designs for such products are now invariably semiconductor-based.
Footnotes:
Works cited Symons, Robert S. (1998). "Tubes: Still vital after all these years". IEEE Spectrum. 35 (4): 52–63. doi:10.1109/6.666962. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Basic helix-loop-helix leucine zipper transcription factors**
Basic helix-loop-helix leucine zipper transcription factors:
Basic helix-loop-helix leucine zipper transcription factors are, as their name indicates, transcription factors containing both Basic helix-loop-helix and leucine zipper motifs.
Examples include Microphthalmia-associated transcription factor and Sterol regulatory element binding protein (SREBP). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Knee taping**
Knee taping:
Knee taping (also known as patellar taping) is a procedure performed by physiotherapists or physicians to alleviate the symptoms of patellofemoral pain. Though knee taping has been shown to offer short-term pain relief, its long-term efficacy is confounded by several studies. The mechanism of action by which it alleviates pain is unknown, though it has been suggested by physicians that it could correct patella position, facilitate/inhibit quadriceps components or bear stress associated with peripatellar tissues or patellar compression (Wilson, T). Evidence for these suggestions, however, has been contradictory or absent.
Types of tape:
A pre-wrap is a protective tape. Its purpose is to create a firm surface for further taping.
Adhesive tape or wrap is applied to the cover tape and must not be applied directly to the skin. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Inductively coupled plasma mass spectrometry**
Inductively coupled plasma mass spectrometry:
Inductively coupled plasma mass spectrometry (ICP-MS) is a type of mass spectrometry that uses an inductively coupled plasma to ionize the sample. It atomizes the sample and creates atomic and small polyatomic ions, which are then detected. It is known and used for its ability to detect metals and several non-metals in liquid samples at very low concentrations. It can detect different isotopes of the same element, which makes it a versatile tool in isotopic labeling.
Inductively coupled plasma mass spectrometry:
Compared to atomic absorption spectroscopy, ICP-MS has greater speed, precision, and sensitivity. However, compared with other types of mass spectrometry, such as thermal ionization mass spectrometry (TIMS) and glow discharge mass spectrometry (GD-MS), ICP-MS introduces many interfering species: argon from the plasma, component gases of air that leak through the cone orifices, and contamination from glassware and the cones.
Components:
Inductively coupled plasma An inductively coupled plasma is a plasma that is energized (ionized) by inductively heating the gas with an electromagnetic coil, and contains a sufficient concentration of ions and electrons to make the gas electrically conductive. Not all of the gas needs to be ionized for the gas to have the characteristics of a plasma; as little as 1% ionization creates a plasma. The plasmas used in spectrochemical analysis are essentially electrically neutral, with each positive charge on an ion balanced by a free electron. In these plasmas the positive ions are almost all singly charged and there are few negative ions, so there are nearly equal numbers of ions and electrons in each unit volume of plasma.
Components:
The ICPs have two operation modes, called capacitive (E) mode with low plasma density and inductive (H) mode with high plasma density, and E to H heating mode transition occurs with external inputs. The Inductively Coupled Plasma Mass Spectrometry is operated in the H mode.
Components:
What makes Inductively Coupled Plasma Mass Spectrometry (ICP-MS) unique to other forms of inorganic mass spectrometry is its ability to sample the analyte continuously, without interruption. This is in contrast to other forms of inorganic mass spectrometry; Glow Discharge Mass Spectrometry (GDMS) and Thermal Ionization Mass Spectrometry (TIMS), that require a two-stage process: Insert sample(s) into a vacuum chamber, seal the vacuum chamber, pump down the vacuum, energize sample, thereby sending ions into the mass analyzer. With ICP-MS the sample to be analyzed is sitting at atmospheric pressure. Through the effective use of differential pumping; multiple vacuum stages separate by differential apertures (holes), the ions created in the argon plasma are, with the aid of various electrostatic focusing techniques, transmitted through the mass analyzer to the detector(s) and counted. Not only does this enable the analyst to radically increase sample throughput (amount of samples over time), but has also made it possible to do what is called "time resolved acquisition". Hyphenated techniques like Liquid Chromatography ICP-MS (LC-ICP-MS); Laser Ablation ICP-MS (LA-ICP-MS); Flow Injection ICP-MS (FIA-ICP-MS), etc. have benefited from this relatively new technology. It has stimulated the development new tools for research including geochemistry and forensic chemistry; biochemistry and oceanography. Additionally, increases in sample throughput from dozens of samples a day to hundreds of samples a day have revolutionized environmental analysis, reducing costs. Fundamentally, this is all due to the fact that while the sample resides at environmental pressure, the analyzer and detector are at 1/10,000,000 of that same pressure during normal operation.
Components:
An inductively coupled plasma (ICP) for spectrometry is sustained in a torch that consists of three concentric tubes, usually made of quartz, although the inner tube (injector) can be sapphire if hydrofluoric acid is being used. The end of this torch is placed inside an induction coil supplied with a radio-frequency electric current. A flow of argon gas (usually 13 to 18 liters per minute) is introduced between the two outermost tubes of the torch and an electric spark is applied for a short time to introduce free electrons into the gas stream. These electrons interact with the radio-frequency magnetic field of the induction coil and are accelerated first in one direction, then the other, as the field changes at high frequency (usually 27.12 million cycles per second). The accelerated electrons collide with argon atoms, and sometimes a collision causes an argon atom to part with one of its electrons. The released electron is in turn accelerated by the rapidly changing magnetic field. The process continues until the rate of release of new electrons in collisions is balanced by the rate of recombination of electrons with argon ions (atoms that have lost an electron). This produces a ‘fireball’ that consists mostly of argon atoms with a rather small fraction of free electrons and argon ions. The temperature of the plasma is very high, of the order of 10,000 K. The plasma also produces ultraviolet light, so for safety should not be viewed directly.
Components:
The ICP can be retained in the quartz torch because the flow of gas between the two outermost tubes keeps the plasma away from the walls of the torch. A second flow of argon (around 1 liter per minute) is usually introduced between the central tube and the intermediate tube to keep the plasma away from the end of the central tube. A third flow (again usually around 1 liter per minute) of gas is introduced into the central tube of the torch. This gas flow passes through the centre of the plasma, where it forms a channel that is cooler than the surrounding plasma but still much hotter than a chemical flame. Samples to be analyzed are introduced into this central channel, usually as a mist of liquid formed by passing the liquid sample into a nebulizer.
Components:
To maximise plasma temperature (and hence ionisation efficiency) and stability, the sample should be introduced through the central tube with as little liquid (solvent load) as possible, and with consistent droplet sizes. A nebuliser can be used for liquid samples, followed by a spray chamber to remove larger droplets, or a desolvating nebuliser can be used to evaporate most of the solvent before it reaches the torch. Solid samples can also be introduced using laser ablation. The sample enters the central channel of the ICP, evaporates, molecules break apart, and then the constituent atoms ionise. At the temperatures prevailing in the plasma a significant proportion of the atoms of many chemical elements are ionized, each atom losing its most loosely bound electron to form a singly charged ion. The plasma temperature is selected to maximise ionisation efficiency for elements with a high first ionisation energy, while minimising second ionisation (double charging) for elements that have a low second ionisation energy.
Components:
Mass spectrometry For coupling to mass spectrometry, the ions from the plasma are extracted through a series of cones into a mass spectrometer, usually a quadrupole. The ions are separated on the basis of their mass-to-charge ratio and a detector receives an ion signal proportional to the concentration.
The concentration of a sample can be determined through calibration with certified reference material such as single or multi-element reference standards. ICP-MS also lends itself to quantitative determinations through isotope dilution, a single point method based on an isotopically enriched standard. In order to increase reproducibility and compensate errors but sensitivity variation, an internal standard can be added.
Other mass analyzers coupled to ICP systems include double focusing magnetic-electrostatic sector systems with both single and multiple collector, as well as time of flight systems (both axial and orthogonal accelerators have been used).
Applications:
One of the largest volume uses for ICP-MS is in the medical and forensic field, specifically, toxicology. A physician may order a metal assay for a number of reasons, such as suspicion of heavy metal poisoning, metabolic concerns, and even hepatological issues. Depending on the specific parameters unique to each patient's diagnostic plan, samples collected for analysis can range from whole blood, urine, plasma, serum, to even packed red blood cells. Another primary use for this instrument lies in the environmental field. Such applications include water testing for municipalities or private individuals all the way to soil, water and other material analysis for industrial purposes.In recent years, industrial and biological monitoring has presented another major need for metal analysis via ICP-MS. Individuals working in factories where exposure to metals is likely and unavoidable, such as a battery factory, are required by their employer to have their blood or urine analyzed for metal toxicity on a regular basis. This monitoring has become a mandatory practice implemented by the U.S. Occupational Safety and Health Administration, in an effort to protect workers from their work environment and ensure proper rotation of work duties (i.e. rotating employees from a high exposure position to a low exposure position).
Applications:
ICP-MS is also used widely in the geochemistry field for radiometric dating, in which it is used to analyze relative abundance of different isotopes, in particular uranium and lead. ICP-MS is more suitable for this application than the previously used thermal ionization mass spectrometry, as species with high ionization energy such as osmium and tungsten can be easily ionized. For high precision ratio work, multiple collector instruments are normally used to reduce the effect noise on the calculated ratios.
Applications:
In the field of flow cytometry, a new technique uses ICP-MS to replace the traditional fluorochromes. Briefly, instead of labelling antibodies (or other biological probes) with fluorochromes, each antibody is labelled with a distinct combinations of lanthanides. When the sample of interest is analysed by ICP-MS in a specialised flow cytometer, each antibody can be identified and quantitated by virtue of a distinct ICP "footprint". In theory, hundreds of different biological probes can thus be analysed in an individual cell, at a rate of ca. 1,000 cells per second. Because elements are easily distinguished in ICP-MS, the problem of compensation in multiplex flow cytometry is effectively eliminated.
Applications:
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful technique for the elemental analysis of a wide variety of materials encountered in forensic casework. (LA-ICP-MS) has already successfully been applied to applications in forensics, metals, glasses, soils, car paints, bones and teeth, printing inks, trace elemental, fingerprint, and paper. Among these, forensic glass analysis stands out as an application for which this technique has great utility to provide highly.
Applications:
Car hit and runs, burglaries, assaults, drive-by shootings and bombings such as these situations may cause glass fragments that could be used as evidence of association in glass transfer conditions. LA-ICP-MS is considered one of the best techniques for analysis of glass due to the short time for sample preparation and sample, small sample size of less than 250 nanograms. In addition there is no need for complex procedure and handling of dangerous materials that is used for digestion of the samples. This allows detecting major, minor and tracing elements with high level of precision and accuracy. There are set of properties that are used to measure glass sample such as physical and optical properties including color, thickness, density, refractive index (RI) and also, if necessary, elemental analysis can be conducted in order to enhance the value of an association.
Applications:
Pharmaceutical industry In the pharmaceutical industry, ICP-MS is used for detecting inorganic impurities in pharmaceuticals and their ingredients. New and reduced maximum permitted exposure levels of heavy metals from dietary supplements, introduced in USP (United States Pharmacopeia) «〈232〉Elemental Impurities—Limits» and USP «〈232〉Elemental Impurities—Procedures», will increase the need for ICP-MS technology, where, previously, other analytic methods have been sufficient.
Applications:
Cosmetics, such as lipstick, recovered from a crime scene may provide valuable forensic information. Lipstick smears left on cigarette butts, glassware, clothing, bedding; napkins, paper, etc. may be valuable evidence. Lipstick recovered from clothing or skin may also indicate physical contact between individuals. Forensic analysis of recovered lipstick smear evidence can provide valuable information on the recent activities of a victim or suspect. Trace elemental analysis of lipstick smears could be used to complement existing visual comparative procedures to determine the lipstick brand and color.
Applications:
Single Particle Inductively Coupled Plasma Mass Spectroscopy (SP ICP-MS) was designed for particle suspensions in 2000 by Claude Degueldre. He first tested this new methodology at the Forel Institute of the University of Geneva and presented this new analytical approach at the 'Colloid 2oo2' symposium during the spring 2002 meeting of the EMRS, and in the proceedings in 2003. This study presents the theory of SP ICP-MS and the results of tests carried out on clay particles (montmorillonite) as well as other suspensions of colloids. This method was then tested on thorium dioxide nanoparticles by Degueldre & Favarger (2004), zirconium dioxide by Degueldre et al (2004) and gold nanoparticles, which are used as a substrate in nanopharmacy, and published by Degueldre et al (2006). Subsequently, the study of uranium dioxide nano- and micro-particles gave rise to a detailed publication, Ref. Degueldre et al (2006). Since 2010 the interest for SP ICP-MS has exploded.
Applications:
Previous forensic techniques employed for the organic analysis of lipsticks by compositional comparison include thin layer chromatography (TLC), gas chromatography (GC), and high-performance liquid chromatography (HPLC). These methods provide useful information regarding the identification of lipsticks. However, they all require long sample preparation times and destroy the sample. Nondestructive techniques for the forensic analysis of lipstick smears include UV fluorescence observation combined with purge-and-trap gas chromatography, microspectrophotometry and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and Raman spectroscopy.
Applications:
Metal speciation A growing trend in the world of elemental analysis has revolved around the speciation, or determination of oxidation state of certain metals such as chromium and arsenic. The toxicity of those elements varies with the oxidation state, so new regulations from food authorities requires speciation of some elements. One of the primary techniques to achieve this is to separate the chemical species with high-performance liquid chromatography (HPLC) or field flow fractionation (FFF) and then measure the concentrations with ICP-MS.
Applications:
Quantification of proteins and biomolecules There is an increasing trend of using ICP-MS as a tool in speciation analysis, which normally involves a front end chromatograph separation and an elemental selective detector, such as AAS and ICP-MS. For example, ICP-MS may be combined with size exclusion chromatography and quantitative preparative native continuous polyacrylamide gel electrophoresis (QPNC-PAGE) for identifying and quantifying native metal cofactor containing proteins in biofluids. Also the phosphorylation status of proteins can be analyzed.
Applications:
In 2007, a new type of protein tagging reagents called metal-coded affinity tags (MeCAT) were introduced to label proteins quantitatively with metals, especially lanthanides. The MeCAT labelling allows relative and absolute quantification of all kind of proteins or other biomolecules like peptides. MeCAT comprises a site-specific biomolecule tagging group with at least a strong chelate group which binds metals. The MeCAT labelled proteins can be accurately quantified by ICP-MS down to low attomol amount of analyte which is at least 2–3 orders of magnitude more sensitive than other mass spectrometry based quantification methods. By introducing several MeCAT labels to a biomolecule and further optimization of LC-ICP-MS detection limits in the zeptomol range are within the realm of possibility. By using different lanthanides MeCAT multiplexing can be used for pharmacokinetics of proteins and peptides or the analysis of the differential expression of proteins (proteomics) e.g. in biological fluids. Breakable PAGE SDS-PAGE (DPAGE, dissolvable PAGE), two-dimensional gel electrophoresis or chromatography is used for separation of MeCAT labelled proteins. Flow-injection ICP-MS analysis of protein bands or spots from DPAGE SDS-PAGE gels can be easily performed by dissolving the DPAGE gel after electrophoresis and staining of the gel. MeCAT labelled proteins are identified and relatively quantified on peptide level by MALDI-MS or ESI-MS.
Applications:
Elemental analysis The ICP-MS allows determination of elements with atomic mass ranges 7 to 250 (Li to U), and sometimes higher. Some masses are prohibited such as 40 due to the abundance of argon in the sample. Other blocked regions may include mass 80 (due to the argon dimer), and mass 56 (due to ArO), the latter of which greatly hinders Fe analysis unless the instrumentation is fitted with a reaction chamber. Such interferences can be reduced by using a high resolution ICP-MS (HR-ICP-MS) which uses two or more slits to constrict the beam and distinguish between nearby peaks. This comes at the cost of sensitivity. For example, distinguishing iron from argon requires a resolving power of about 10,000, which may reduce the iron sensitivity by around 99%. Another solution for some interfering species is the use of a collision chamber, as explained in collision reaction cell article.
Applications:
A single collector ICP-MS may use a multiplier in pulse counting mode to amplify very low signals, an attenuation grid or a multiplier in analogue mode to detect medium signals, and a Faraday cup/bucket to detect larger signals. A multi-collector ICP-MS may have more than one of any of these, normally Faraday buckets which are much less expensive. With this combination, a dynamic range of 12 orders of magnitude, from 1 ppq to 100 ppm is possible.
Applications:
ICP-MS is a method of choice for the determination of cadmium in biological samples.Unlike atomic absorption spectroscopy, which can only measure a single element at a time, ICP-MS has the capability to scan for all elements simultaneously. This allows rapid sample processing. A simultaneous ICP-MS that can record the entire analytical spectrum from lithium to uranium in every analysis won the Silver Award at the 2010 Pittcon Editors' Awards. An ICP-MS may use multiple scan modes, each one striking a different balance between speed and precision. Using the magnet alone to scan is slow, due to hysteresis, but is precise. Electrostatic plates can be used in addition to the magnet to increase the speed, and this, combined with multiple collectors, can allow a scan of every element from Lithium 6 to Uranium Oxide 256 in less than a quarter of a second. For low detection limits, interfering species and high precision, the counting time can increase substantially. The rapid scanning, large dynamic range and large mass range is ideally suited to measuring multiple unknown concentrations and isotope ratios in samples that have had minimal preparation (an advantage over TIMS), for example seawater, urine, and digested whole rock samples. It also lends well to laser ablated rock samples, where the scanning rate is so quick that a real time plot of any number of isotopes is possible. This also allows easy spatial mapping of mineral grains.
Hardware:
In terms of input and output, ICP-MS instrument consumes prepared sample material and translates it into mass-spectral data. Actual analytical procedure takes some time; after that time the instrument can be switched to work on the next sample. Series of such sample measurements requires the instrument to have plasma ignited, meanwhile a number of technical parameters has to be stable in order for the results obtained to have feasibly accurate and precise interpretation. Maintaining the plasma requires a constant supply of carrier gas (usually, pure argon) and increased power consumption of the instrument. When these additional running costs are not considered justified, plasma and most of auxiliary systems can be turned off. In such standby mode only pumps are working to keep proper vacuum in mass-spectrometer.
Hardware:
The constituents of ICP-MS instrument are designed to allow for reproducible and/or stable operation.
Sample introduction The first step in analysis is the introduction of the sample. This has been achieved in ICP-MS through a variety of means.
Hardware:
The most common method is the use of analytical nebulizers. Nebulizer converts liquids into an aerosol, and that aerosol can then be swept into the plasma to create the ions. Nebulizers work best with simple liquid samples (i.e. solutions). However, there have been instances of their use with more complex materials like a slurry. Many varieties of nebulizers have been coupled to ICP-MS, including pneumatic, cross-flow, Babington, ultrasonic, and desolvating types. The aerosol generated is often treated to limit it to only smallest droplets, commonly by means of a Peltier cooled double pass or cyclonic spray chamber. Use of autosamplers makes this easier and faster, especially for routine work and large numbers of samples. A Desolvating Nebuliser (DSN) may also be used; this uses a long heated capillary, coated with a fluoropolymer membrane, to remove most of the solvent and reduce the load on the plasma. Matrix removal introduction systems are sometimes used for samples, such as seawater, where the species of interest are at trace levels, and are surrounded by much more abundant contaminants.
Hardware:
Laser ablation is another method. While being less common in the past, is rapidly becoming popular has been used as a means of sample introduction, thanks to increased ICP-MS scanning speeds. In this method, a pulsed UV laser is focused on the sample and creates a plume of ablated material which can be swept into the plasma. This allows geochemists to spacially map the isotope composition in cross-sections of rock samples, a tool which is lost if the rock is digested and introduced as a liquid sample. Lasers for this task are built to have highly controllable power outputs and uniform radial power distributions, to produce craters which are flat bottomed and of a chosen diameter and depth.
Hardware:
For both Laser Ablation and Desolvating Nebulisers, a small flow of Nitrogen may also be introduced into the Argon flow. Nitrogen exists as a dimer, so has more vibrational modes and is more efficient at receiving energy from the RF coil around the torch.
Other methods of sample introduction are also utilized. Electrothermal vaporization (ETV) and in torch vaporization (ITV) use hot surfaces (graphite or metal, generally) to vaporize samples for introduction. These can use very small amounts of liquids, solids, or slurries. Other methods like vapor generation are also known.
Plasma torch The plasma used in an ICP-MS is made by partially ionizing argon gas (Ar → Ar+ + e−). The energy required for this reaction is obtained by pulsing an alternating electric current in load coil that surrounds the plasma torch with a flow of argon gas.
After the sample is injected, the plasma's extreme temperature causes the sample to separate into individual atoms (atomization). Next, the plasma ionizes these atoms (M → M+ + e−) so that they can be detected by the mass spectrometer.
Hardware:
An inductively coupled plasma (ICP) for spectrometry is sustained in a torch that consists of three concentric tubes, usually made of quartz. The two major designs are the Fassel and Greenfield torches. The end of this torch is placed inside an induction coil supplied with a radio-frequency electric current. A flow of argon gas (usually 14 to 18 liters per minute) is introduced between the two outermost tubes of the torch and an electrical spark is applied for a short time to introduce free electrons into the gas stream. These electrons interact with the radio-frequency magnetic field of the induction coil and are accelerated first in one direction, then the other, as the field changes at high frequency (usually 27.12 MHz or 40 MHz). The accelerated electrons collide with argon atoms, and sometimes a collision causes an argon atom to part with one of its electrons. The released electron is in turn accelerated by the rapidly changing magnetic field. The process continues until the rate of release of new electrons in collisions is balanced by the rate of recombination of electrons with argon ions (atoms that have lost an electron). This produces a ‘fireball’ that consists mostly of argon atoms with a rather small fraction of free electrons and argon ions.
Hardware:
Advantage of argon Making the plasma from argon, instead of other gases, has several advantages. First, argon is abundant (in the atmosphere, as a result of the radioactive decay of potassium) and therefore cheaper than other noble gases. Argon also has a higher first ionization potential than all other elements except He, F, and Ne. Because of this high ionization energy, the reaction (Ar+ + e− → Ar) is more energetically favorable than the reaction (M+ + e− → M). This ensures that the sample remains ionized (as M+) so that the mass spectrometer can detect it.
Hardware:
Argon can be purchased for use with the ICP-MS in either a refrigerated liquid or a gas form. However it is important to note that whichever form of argon purchased, it should have a guaranteed purity of 99.9% Argon at a minimum. It is important to determine which type of argon will be best suited for the specific situation. Liquid argon is typically cheaper and can be stored in a greater quantity as opposed to the gas form, which is more expensive and takes up more tank space. If the instrument is in an environment where it gets infrequent use, then buying argon in the gas state will be most appropriate as it will be more than enough to suit smaller run times and gas in the cylinder will remain stable for longer periods of time, whereas liquid argon will suffer loss to the environment due to venting of the tank when stored over extended time frames. However, if the ICP-MS is to be used routinely and is on and running for eight or more hours each day for several days a week, then going with liquid argon will be the most suitable. If there are to be multiple ICP-MS instruments running for long periods of time, then it will most likely be beneficial for the laboratory to install a bulk or micro bulk argon tank which will be maintained by a gas supply company, thus eliminating the need to change out tanks frequently as well as minimizing loss of argon that is left over in each used tank as well as down time for tank changeover.
Hardware:
Helium can be used either in place of, or mixed with, argon for plasma generation. Helium's higher first ionisation energy allows greater ionisation and therefore higher sensitivity for hard-to-ionise elements. The use of pure helium also avoids argon-based intereferences such as ArO. However, many of the interferences can be mitigated by use of a collision cell, and the greater cost of helium has prevented its use in commercial ICP-MS.
Hardware:
Transfer of ions into vacuum The carrier gas is sent through the central channel and into the very hot plasma. The sample is then exposed to radio frequency which converts the gas into a plasma. The high temperature of the plasma is sufficient to cause a very large portion of the sample to form ions. This fraction of ionization can approach 100% for some elements (e.g. sodium), but this is dependent on the ionization potential. A fraction of the formed ions passes through a ~1 mm hole (sampler cone) and then a ~0.4 mm hole (skimmer cone). The purpose of which is to allow a vacuum that is required by the mass spectrometer.
Hardware:
The vacuum is created and maintained by a series of pumps. The first stage is usually based on a roughing pump, most commonly a standard rotary vane pump. This removes most of the gas and typically reaches a pressure of around 133 Pa. Later stages have their vacuum generated by more powerful vacuum systems, most often turbomolecular pumps. Older instruments may have used oil diffusion pumps for high vacuum regions.
Hardware:
Ion optics Before mass separation, a beam of positive ions has to be extracted from the plasma and focused into the mass-analyzer. It is important to separate the ions from UV photons, energetic neutrals and from any solid particles that may have been carried into the instrument from the ICP. Traditionally, ICP-MS instruments have used transmitting ion lens arrangements for this purpose. Examples include the Einzel lens, the Barrel lens, Agilent's Omega Lens and Perkin-Elmer's Shadow Stop. Another approach is to use ion guides (quadrupoles, hexapoles, or octopoles) to guide the ions into mass analyzer along a path away from the trajectory of photons or neutral particles. Yet another approach is Varian patented used by Analytik Jena ICP-MS 90 degrees reflecting parabolic "Ion Mirror" optics, which are claimed to provide more efficient ion transport into the mass-analyzer, resulting in better sensitivity and reduced background. Analytik Jena ICP-MS PQMS is the most sensitive instrument on the market.A sector ICP-MS will commonly have four sections: an extraction acceleration region, steering lenses, an electrostatic sector and a magnetic sector. The first region takes ions from the plasma and accelerates them using a high voltage. The second uses may use a combination of parallel plates, rings, quadrupoles, hexapoles and octopoles to steer, shape and focus the beam so that the resulting peaks are symmetrical, flat topped and have high transmission. The electrostatic sector may be before or after the magnetic sector depending on the particular instrument, and reduces the spread in kinetic energy caused by the plasma. This spread is particularly large for ICP-MS, being larger than Glow Discharge and much larger than TIMS. The geometry of the instrument is chosen so that the instrument the combined focal point of the electrostatic and magnetic sectors is at the collector, known as Double Focussing (or Double Focussing).
Hardware:
If the mass of interest has a low sensitivity and is just below a much larger peak, the low mass tail from this larger peak can intrude onto the mass of interest. A Retardation Filter might be used to reduce this tail. This sits near the collector, and applies a voltage equal but opposite to the accelerating voltage; any ions that have lost energy while flying around the instrument will be decelerated to rest by the filter.
Hardware:
Collision reaction cell and iCRC The collision/reaction cell is used to remove interfering ions through ion/neutral reactions. Collision/reaction cells are known under several names. The dynamic reaction cell is located before the quadrupole in the ICP-MS device. The chamber has a quadrupole and can be filled with reaction (or collision) gases (ammonia, methane, oxygen or hydrogen), with one gas type at a time or a mixture of two of them, which reacts with the introduced sample, eliminating some of the interference.
Hardware:
The integrated Collisional Reaction Cell (iCRC) used by Analytik Jena ICP-MS is a mini-collision cell installed in front of the parabolic ion mirror optics that removes interfering ions by injecting a collisional gas (He), or a reactive gas (H2), or a mixture of the two, directly into the plasma as it flows through the skimmer cone and/or the sampler cone. The iCRC removed interfering ions using a collisional kinetic energy discrimination (KED) phenomenon and chemical reactions with interfering ions similarly to traditionally used larger collision cells.
Routine maintenance:
As with any piece of instrumentation or equipment, there are many aspects of maintenance that need to be encompassed by daily, weekly and annual procedures. The frequency of maintenance is typically determined by the sample volume and cumulative run time that the instrument is subjected to.
Routine maintenance:
One of the first things that should be carried out before the calibration of the ICP-MS is a sensitivity check and optimization. This ensures that the operator is aware of any possible issues with the instrument and if so, may address them before beginning a calibration. Typical indicators of sensitivity are Rhodium levels, Cerium/Oxide ratios and DI water blanks. One common standard practice is to measure a standard tuning solution provided by the ICP manufacturer every time the plasma torch is started. Then the instrument is auto-calibrated for optimum sensitivity and the operator obtains a report providing certain parameters such as sensitivity, mass resolution and estimated amount of oxidized species and double-positive charged species.
Routine maintenance:
One of the most frequent forms of routine maintenance is replacing sample and waste tubing on the peristaltic pump, as these tubes can get worn fairly quickly resulting in holes and clogs in the sample line, resulting in skewed results. Other parts that will need regular cleaning and/or replacing are sample tips, nebulizer tips, sample cones, skimmer cones, injector tubes, torches and lenses. It may also be necessary to change the oil in the interface roughing pump as well as the vacuum backing pump, depending on the workload put on the instrument.
Sample preparation:
For most clinical methods using ICP-MS, there is a relatively simple and quick sample prep process. The main component to the sample is an internal standard, which also serves as the diluent. This internal standard consists primarily of deionized water, with nitric or hydrochloric acid, and Indium and/or Gallium. The addition of volatile acids allows for the sample to decompose into its gaseous components in the plasma which minimizes the ability for concentrated salts and solvent loads to clog the cones and contaminate the instrument. Depending on the sample type, usually 5 mL of the internal standard is added to a test tube along with 10–500 microliters of sample. This mixture is then vortexed for several seconds or until mixed well and then loaded onto the autosampler tray.
Sample preparation:
For other applications that may involve very viscous samples or samples that have particulate matter, a process known as sample digestion may have to be carried out, before it can be pipetted and analyzed. This adds an extra first step to the above process, and therefore makes the sample prep more lengthy. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Pi Ursae Majoris**
Pi Ursae Majoris:
The Bayer designation Pi Ursae Majoris (π UMa, π Ursae Majoris) is shared by two stars in the constellation Ursa Major: Pi¹ Ursae Majoris (3 Ursae Majoris) Pi² Ursae Majoris (4 Ursae Majoris)They are separated by 0.70° in the sky. They are sometimes given the name Muscida, which can also refer to ο Ursae Majoris.
The two stars, Pi¹ and Pi² together, are considered an optical double star. They are not a binary star, in that they are not gravitationally linked, but they are close to each other as seen in the sky, and so are optically associated. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Functional requirement**
Functional requirement:
In software engineering and systems engineering, a functional requirement defines a function of a system or its component, where a function is described as a summary (or specification or statement) of behavior between inputs and outputs.Functional requirements may involve calculations, technical details, data manipulation and processing, and other specific functionality that define what a system is supposed to accomplish. Behavioral requirements describe all the cases where the system uses the functional requirements, these are captured in use cases. Functional requirements are supported by non-functional requirements (also known as "quality requirements"), which impose constraints on the design or implementation (such as performance requirements, security, or reliability). Generally, functional requirements are expressed in the form "system must do <requirement>," while non-functional requirements take the form "system shall be <requirement>." The plan for implementing functional requirements is detailed in the system design, whereas non-functional requirements are detailed in the system architecture.As defined in requirements engineering, functional requirements specify particular results of a system. This should be contrasted with non-functional requirements, which specify overall characteristics such as cost and reliability. Functional requirements drive the application architecture of a system, while non-functional requirements drive the technical architecture of a system.In some cases a requirements analyst generates use cases after gathering and validating a set of functional requirements. The hierarchy of functional requirements collection and change, broadly speaking, is: user/stakeholder request → analyze → use case → incorporate. Stakeholders make a request; systems engineers attempt to discuss, observe, and understand the aspects of the requirement; use cases, entity relationship diagrams, and other models are built to validate the requirement; and, if documented and approved, the requirement is implemented/incorporated. Each use case illustrates behavioral scenarios through one or more functional requirements. Often, though, an analyst will begin by eliciting a set of use cases, from which the analyst can derive the functional requirements that must be implemented to allow a user to perform each use case.
Process:
A typical functional requirement will contain a unique name and number, a brief summary, and a rationale. This information is used to help the reader understand why the requirement is needed, and to track the requirement through the development of the system. The crux of the requirement is the description of the required behavior, which must be clear and readable. The described behavior may come from organizational or business rules, or it may be discovered through elicitation sessions with users, stakeholders, and other experts within the organization. Many requirements may be uncovered during the use case development. When this happens, the requirements analyst may create a placeholder requirement with a name and summary, and research the details later, to be filled in when they are better known. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Surgical nursing**
Surgical nursing:
A surgical nurse, also referred to as a theatre nurse or scrub nurse, specializes in perioperative care, providing care to patients before, during and after surgery. To become a theatre nurse, Registered Nurses or Enrolled Nurses must complete extra training. Theatre nurses can focus on different speciality areas, depending on which they are interested in.
Surgical nursing:
There are many different phases during surgery where the theatre nurse is needed to support and assist the patient, surgeons, surgical technicians, nurse anaesthetists and nurse practitioners. Pre-operative, the nurse must help to prepare the patient and operating room for the surgery. During the surgery, they assist the anaesthetist and surgeons when they are needed. The last phase is post-operative, ensuring that the patients are provided with suitable care and treatments.
Surgical nursing:
People who want to become surgical nurses attend nursing school and specialize in surgical nursing. They are often required to pass examinations administered by the government or by nursing certification boards before being allowed to work as nurses, and they may also be expected to attend periodic continuing education classes so that they keep up with developments in the nursing field.In the UK and Australia, surgical patients (those who have undergone a minor or major surgical procedure) are nursed on different wards from medical patients. Nursing practice on surgical wards differs from that of medical wards.
Surgical nursing:
Surgical nurses may practice in different types of surgery: General surgery (e.g. appendectomy, gallbladder removal) Vascular surgery (e.g. varicose vein surgery, aortic aneurysm repair) Colo-rectal surgery (e.g. stoma formation) Surgical Oncology (e.g. breast surgery, tumour resections) Orthopaedic surgery (e.g. knee or hip replacements, fracture repair) Urological surgery (e.g. prostate surgery) Day surgery (or ambulatory surgery, where a patient is discharged within 24 hours)Surgical nurses are responsible for approximately six patients, depending on the nature of the surgical ward. Intensive Care and High-Dependency units usually have one to two nurses per patient.
Duties:
Theatre nurses are part of the perioperative surgical team; they work alongside surgeons, surgical technician, nurse anaesthetists and nurse practitioners.
In surgery there are three main phases: preoperative, intraoperative and postoperative. These phases collectively are known as the perioperative period. Each phase is related to specific activities carried out and skills needed for different stages of nursing.
Duties:
Preoperative Phase This stage is undertaken when the patient decides to have surgery. It may include discussing with the patients all the benefits of the procedure but also the dangers that could occur. This is an opportunity for the patient to discuss any concerns they may have. Also the theatre nurses must make sure that the patients are in good condition, before going ahead with the surgery. While it is very important to prepare a patient physically, it is also important to mentally prepare a patient prior to surgery. A surgical nurse will help prepare the patient using various methods often including family members depending on the situation. The patient will normally express any concerns about the surgery to the nurse; this information will be passed on to other hospital staff including the surgeon. The appropriate actions will be taken dependent on the situation.
Duties:
Intraoperative Phase This stage begins when the ward nurse, who has prepared the patient for surgery, delivers the patient and their notes to the theatre and/or anaesthetic nurse. Many checks are undertaken at this stage to ensure a safe environment for the patient and the theatre staff. The theatre nurse works to maintain a sterile environment and to ensure the surgical equipment is working well. The nurse also organises all surgical instruments and ensures all supplies needed during the surgery are available.
Duties:
Postoperative Phase This phase begins when the theatre/anaesthetic nurse delivers the patient's notes to the nurses and staff in the Post-Anaesthetic Care Unit (PACU). This can also be known as the recovery room. Here the nurse's immediate attention is on checking the patient's airway and breathing. In this phase nurses also attend to pain relief and any other complications following surgery. These nurses, often in day surgery cases, attend to provide patients and their caregivers with support and instructions and requirements needed for home care.The first twenty-four hours post surgery are critical, and many procedures are required to monitor the patient. Observations of the patient need to be taken and recorded every fifteen minutes. General observations include heart rate, blood pressure, temperature, respiratory rate and oxygen saturation. Further post-operative tasks for a surgical nurse include: urine output, assessment of wound sites, replacing intravenous requirements and reporting any abnormalities. To aid recovery, It may be necessary for the nurse to be free of the world
Credentials:
To become a surgical nurse, CCTC one must have undertaken appropriate training, and be registered with the state nursing board (Nursing and Midwifery Council, UK; An Bord Altranais, Rep. of Ireland). In Australia, both Registered Nurses and Enrolled Nurses work in surgical wards. Registered nursing received their training over a longer period of time, as they receive a university degree. To become a registered nurse you must complete a bachelor's degree of nursing which takes up to 3 years. Enrolled Nurses complete a Diploma of Nursing which is a full-time course over 12 –16 months at Technical and Further Education (TAFE). In Australia, the education standards are nationwide, requiring an undergraduate nursing degree and graduate diploma in perioperative nursing. The undergraduate degree has a full-time study duration of three years at the University of Notre Dame. The post graduate diploma in preoperative nursing has some prerequisites including; undergraduate nursing degree, be a full-time employee of the Fremantle Health Service, hold a current licence to practice as a level one registered nurse and have at least one year of postgraduate experience. With these qualifications it is possible to become a surgical nurse in Australia.
Credentials:
The Graduate Diploma in Perioperative Nursing is available 1 year full-time or equivalent part-time and is developed to qualify the registered nurse to enhance knowledge and combine skills to work as a specialist within the perioperative field.
Types of surgical nurse:
In the theatre room there are two main types of nurses: a scrub nurse and a circulation nurse. The scrub nurse must make sure they are familiar with and well educated about every piece of operational equipment; as on request they are required to provide the surgeons with the equipment needed. The scrub nurse is also responsible for making sure all operating equipment is accounted for before and after the operation.
Types of surgical nurse:
The scrub nurse is responsible for many important technical duties. These can include ensuring they have correctly prepared the surgical instruments and trolleys and ensuring that all operating supplies have been sterilised. Non-technical skills are also important for the scrub nurse role. These can include cognitive skills such as formulating appropriate decisions. Another non-technical skill required is being able to work well within a team, for example, the ability to communicate well with the surgical team during a procedure.
Types of surgical nurse:
A circulation nurse has many similar responsibilities; they should ensure that the operating room is clear and uncontaminated by previous surgeries or other infections. They are also there to collect, open, clear and sterilise packets containing surgical equipment.
Surgical Nurse Interaction with Patients:
It is important for surgical nurses to have a thorough understanding of their roles and interactions with patients and their immediate families within a surgical care environment. One vital role for a surgical nurse is to provide support and confidence to their patient while they are in hospital. Nurses are also required to possess good communication skills and maintain a professional relationship with their patient. It is important for the nurse to build a trusting relationship with their patient but this can prove difficult within the short time available. Due to the fast-paced surgical surroundings, there is little time for surgical nurses to provide information and reassurance before and after surgery. Many patients feel vulnerable and anxious prior to their surgical procedure and it is important for the surgical nurse to recognise their patient's need for psychological support. It is therefore important for the surgical nurse to understand their role in relation to the patient. By understanding the emotional needs of their patients, surgical nurses’ perspectives and conduct towards their patient will influence the patient's experience.
Preoperative Teaching:
Preoperative teaching if delivered competently is an important aspect of patient care. Positive effects of preoperative teaching include a reduction in patients’ anxiety levels, healing time, complications post- surgery, pain relief usage and an increase in satisfied and co-operative patient's in regard to their procedure and treatment. Preoperative teaching is essential to a patient's understanding of the surgical procedure and to help them prepare for postoperative healing.Preoperative teaching is usually undertaken before the day of surgery. This can be delivered by verbal and/or written instructions. Patients may also have an appointment scheduled with the perioperative nurse to talk over any concerns regarding the procedure. Teaching is further discussed on the day of surgery and also before the patient is discharged to leave the hospital.
Potential Careers:
Nurses who work in the operating theatre become specialists in the field or a specific sub speciality. Once you find a specialist field or specific sub speciality you enjoy working in, the nurse will commence as a junior nurse. After gaining a large amount of knowledge and skills set with experience, if the nurse chooses to become more of an expert in this field, the theatre nurse may do a postgraduate certificate or diploma to become a Clinical Nurse for that speciality. The salary for a surgical nurse in Australia can range from $47,721 to $80,160 with an average of $57,103 this data was recorded in March 2016.
Professional Associations - Perioperative Nursing Associations:
The role of professional associations is to protect, increase and promote common interests of their members. They provide opportunities such as networking, clinical education and research grants. Each Australian State has their own group which form a subdivision of ACORN (Australian College of Perioperative Nurses). Western Australia's group is the Operating Nurses Association of Western Australia (ORNA). Both ACORN and ORNA have a website which provides information about their organisation. These websites are: www.acorn.org.au and ornawa.org | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**SimLife**
SimLife:
SimLife: The Genetic Playground is a video game produced by Maxis in 1992. The concept of the game is to simulate an ecosystem; players may modify the genetics of the plants and animals that inhabit the virtual world. The point of this game is to experiment and create a self-sustaining ecosystem. SimLife was re-released in 1993 as part of the SimClassics Volume 1 compilation, alongside SimCity Classic and SimAnt for PC, Mac and Amiga.
Development:
The producers of SimLife refer to it as "The Genetic Playground". The game allows users to explore the interaction of life-forms and environments. Users can manipulate the genetics of both plants and animals to determine whether these new species could survive in the Earth's various environments. Players can also create new worlds with distinctive environments to see how certain species (earth's species or their own) fare within them.
Development:
SimLife gives players the power to: Create and modify worlds.
Create and modify plants and animals at the genetic level. Exclusive animals appearing in this game are the Killer Penguin, the Monkeyphant, and the Orgot.
Design environments and ecosystems.
Study genetics in action.
Simulate and control evolution.
Change the physics of the universe in your computer.
Reception:
Computer Gaming World in 1993 praised SimLife, stating that "By neatly bridging the gap between entertainment and education, SL brings the engrossing science of genetics within reach of any interested person". Games Finder gave SimLife a score of 7 out of 10.In 1993, SimLife received a Codie award from the Software Publishers Association for Best Simulation. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Tokyo Blackout**
Tokyo Blackout:
Tokyo Blackout (首都消失, Shuto shōshitsu) (Disappearance of the Capital) is a 1987 Japanese science fiction film directed by Toshio Masuda. It is based on Sakyo Komatsu's novel Shuto shōshitsu which won the 6th Nihon SF Taisho Award in 1985. The film's score was composed by Maurice Jarre, and special effects were directed by Teruyoshi Nakano.
Plot:
One day, Tokyo and its metropolitan area are suddenly covered by a giant dome-shaped and electromagnetic "cloud" for an unknown reason, and the whole thing seemed to disappear and all communications with the outside of "the cloud" are cut off.
Therefore, governments and scientific researchers in various places were extremely shocked and hurriedly organized to study countermeasures. But people are unable to cross "the cloud" into the Tokyo metropolitan area.
The Soviet Navy fleet is getting close near Hokkaido, and the U.S. is forcing Japan to form a new government. So an emergency national governor's meeting was held, and made the national governor's meeting a transitional agency of state affairs.
Scientists outside "the cloud" try to rescue 20 million lives in "the cloud" by using artificial high-power electromagnetic jammers.
Cast:
Tsunehiko Watase as Tatsuya Asakura, General Manager of Hokuto Electric's Technology Development Department Yūko Natori as Mariko Koide, freelance journalist Shinji Yamashita as Yosuke Tamiya, Kansai Broadcasting Press Isao Natsuyagi as Eiji Sakuma, JASDF Ichirō Zaitsu as Kawamura, Director of Kansai Broadcasting Press Yōko Ishino as Mieko Matsunaga, college student and part-time employee at Hokuto Electric Research Institute Raita Ryū as Horie, Deputy Director, Ministry of Foreign Affairs, International Bureau Ittoku Kishibe as Yasuhara, member of Hokuto Electric Research Institute Yoshie Taira as Yumiko Asakura, wife of Tatsuya Asakura Sei Hiraizumi as Wada, Kansai Broadcasting Society Department Desk Shōji Yasui as Ambassador to the United States Otsuki Kei Taguchi as Ambassador to the United Kingdom Uekusa Renji Ishibashi as Miyoshi, Secretary of the Ministry of Posts and Telecommunications Haruko Katō as Umeko Koide, Mariko's mother Norihei Miki as Matsukichi Kimura Fumio Watanabe as Osaka Prefecture Governor Komuro Hideji Ōtaki as Professor Otawara Tetsurō Tamba as Representative NakataSource for cast
Film production:
Approximately 100 tons of dry ice and various other materials were used to depict the clouds. All staff wore dust masks when shooting using fly ash, a building material. In the scene where people are swallowed by the cloud, high-definition video was used for only 20 seconds. The EP-3E reconnaissance aircraft is a modification of the P-3C aircraft model used in The Return of Godzilla.
Story background and development:
In 1964, Komatsu published the short story Object O (物体O). The story involves a mysterious ring-shaped object 200 kilometers high and 1,000 kilometers wide, which falls around Osaka, cutting it off from the outside world. In contrast with Tokyo Blackout, Object O focuses on events within the ring. Komatsu wrote the novel in serialized form, published among Hokkaido Shimbun, Chunichi Shimbun and Nishinippon Shimbun from December 1983 to December 1984. The book was published by Tokuma Shoten in 1985 and became a bestseller that year, exceeding 1.5 million copies sold. This made it the second best-seller for Komatsu after The Sinking of Japan.
Story background and development:
While the film emphasizes family ties and human drama, the novel has a strong political focus, emphasizing crisis management and Japan’s vulnerability.
Plot of the novel:
The novel begins with Tatsuya Asakura, manager of the planning and general affairs section at the S Heavy Industries Tokyo Headquarters, as he has an unusual experience returning to Tokyo on the Tokaido Shinkansen. Communications and traffic within Tokyo suddenly stop, and the Shinkansen stops at Hamamatsu Station. Here, Asakura meets his friend, JASDF officer Sakuma. At 7:00 AM that day, a cloud with a 60-kilometer diameter radiates from the center of Tokyo, completely enveloping the city to a height of 1,500 meters. Gozo Otawara, an advisor to S Heavy Industries with PHD’s in science and engineering, works with the Central Research Institute of S Heavy Industries and Jonan Medical University to investigate the cloud where Yokohama New Road crosses National Route 16. Tamiya, a classmate of Asakura’s and editor-in-chief of Kitakyushu’s local newspaper Seibu Shimpo accompanies the investigation. The cloud is discovered to consist of water vapor and high levels of ozone and argon. It resists all attempts to penetrate it, including bullets. Humans cannot walk more than 20-30 meters inside before being stopped. Radio waves also don’t reach inside the cloud, so the condition of Tokyo’s inhabitants is unknown. That evening, at the Atsugi base near the Central Research Institute, an emergency meeting is held between the Self Defense Force and US Forces stationed in Japan, involving United Nations and Ministry of Foreign Affairs representatives. The US forces stationed in Japan urge the Japanese to rebuild the government as soon as possible. Tamiya, inspired by the seriousness of the situation, travels to the Kansai headquarters of A Shimbun and works to rebuild the Japanese government. 10 days after the cloud’s appearance, an emergency national governor’s conference is held in Nagoya, establishing Hyogo Prefecture Governor Komuro as the temporary chief representative. The organization is formed by a coalition of prefectures and ordinance-designated cities. It consists of prefectural governors, deputy governors, prefectural assembly chairs, mayors of ordinance-designated cities and representatives of Tokyo, Kanagawa and Saitama prefectures. The basis for legal legitimacy is emergency evacuation under international law, with the premise that the Japanese government is out of touch, but still in existence. Simultaneously, the cloud begins emitting powerful particle beams, damaging or destroying any aircraft or satellites passing above it. An EP-3E reconnaissance aircraft is directly hit by a particle beam, destroying all electronic equipment and killing one crew member from radiation exposure. The United States researches the cloud’s abilities for military purposes, while the Soviet Union detains a Japanese diplomat to increase external pressure on the country. In January of the following year, the Soviet Union sends a large fleet to Hokkaido. A huge earthquake occurs off the coast of Nemuro, and the Soviet fleet is destroyed by a tsunami. At the end of March, about four months after the cloud’s appearance, an international survey of the cloud is conducted. It is determined that the cloud is an automated surveillance device sent by intelligent extraterrestrial life. Shortly afterward, in early April, the cloud disappears as suddenly as it appeared.
Release:
Tokyo Blackout was released theatrically in Japan on 11 January 1987 where it was distributed by Toho. It was released in the United States by Toho International on 29 August 1987. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Seligman Crystal**
Seligman Crystal:
The Seligman Crystal is an award of the International Glaciological Society.
The prize is "awarded from time to time to one who has made an outstanding scientific contribution to glaciology so that the subject is now enriched" and named after Gerald Seligman.
Recipients:
Source: International Glaciological Society Gerald Seligman (1963) H. Bader (1967) J.F. Nye (1969) John W. Glen (1972) B. L. Hansen (1972) S. Evans (1974) Willi Dansgaard (1976) W. B. Kamb (1977) Marcel de Quervain (1982) William Osgood Field, Jr (1983) Johannes Weertman (1983) Mark F. Meier (1985) Gordon de Quetteville Robin (1986) Hans Oeschger (1989) W. F. Weeks (1989) Charles R. Bentley (1990) Akira Higashi (1990) Hans Röthlisberger (1992) Louis Lliboutry (1993) Anthony J. Gow (1995) William F. Budd (1996) Sigfús J. Johnsen (1997) Claude Lorius (1998) Charles F. Raymond (1999) S.C. Colbeck (2000) Geoffrey S. Boulton (2001) Garry K. C. Clarke (2001) Kolumban Hutter (2003) Richard Alley (2005) Lonnie G. Thompson (2007) Paul A. Mayewski (2009) Almut Iken (2011) David E. Sugden (2012) Paul Duval (2013) Richard C.A. Hindmarsh (2019) Douglas R. MacAyeal (2019) Andrew C. Fowler (2020) Catherine Ritz (2020) Adrian Jenkins (2021) | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Subcutaneous fat necrosis of the newborn**
Subcutaneous fat necrosis of the newborn:
Subcutaneous fat necrosis of the newborn is a rare form of lobular panniculitis occurring in newborns that is usually self-remitting and non-recurring. Proposed causes include perinatal stress, local trauma, hypoxia and hypothermia, though the exact cause is unknown. It has been suggested that the brown fat seen in newborns is more sensitive to hypoxic injury than fat seen in adults, and that such hypoxia, usually in the context of a complicated birth, leads to the fat necrosis. Complications can include hypercalcemia, hyperlipidemia, dehydration, hypoglycemia, seizures, vomiting, constipation, and thrombocytopenia, and can present months after the onset of SCFN symptoms.: 490 | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Leaf spring**
Leaf spring:
A leaf spring is a simple form of spring commonly used for suspension in wheeled vehicles. Originally called a laminated or carriage spring, and sometimes referred to as a semi-elliptical spring, elliptical spring, or cart spring, it is one of the oldest forms of vehicle suspension. A leaf spring is one or more narrow, arc-shaped, thin plates that are attached to the axle and chassis in a way that allows the leaf spring to flex vertically in response to irregularities in the road surface. Lateral leaf springs are the most commonly used arrangement, running the length of the vehicle and mounted perpendicular to the wheel axle, but numerous examples of transverse leaf springs exist as well.
Leaf spring:
Leaf springs can serve multiple suspension functions: location, springing, and to some extent damping as well, through interleaf friction. However, this friction is not well controlled, resulting in stiction and irregular suspension motions. For this reason, some manufacturers have used mono-leaf springs.
Operation and basic design:
A leaf spring takes the form of a slender arc-shaped length of spring steel of a rectangular cross-section. In the most common configuration, the center of the arc provides the location for the axle, while loops formed at either end provide for attaching to the vehicle chassis. For very heavy vehicles, a leaf spring can be made from several leaves stacked on top of each other in several layers, often with progressively shorter leaves. The longest leaf is also known as the main, master, or No. 1 leaf, with leaves numbered in descending order of length.: 1–3 The eyes at the end of the leaf spring are formed into the master leaf.: 6 In general, aside from the main leaf, the other leaves are tapered at each end.: 8 Sometimes auxiliary or rebound leaves are part of the main spring pack, in which case the auxiliary leaf closest to the main leaf is No. 1, the next closest is No. 2, etc.: 3 The leaves are attached to each other through the center bolt, which is at or near the mid-point along the length of the leaf spring.: 8 To ensure that leaves remain aligned laterally, several methods can be used, including notches and grooves between leaves or external clips.: 9–12 Spring steels were discovered to be most efficient at approximately 1% carbon content.: 13–15 Individual leaf thickness is specified by the Stubbs or Birmingham gauge, with typical thicknesses ranging between 0.203 to 0.375 in (5.2 to 9.5 mm) (6 to 3/8 or 00 gauge).: 16 The material and dimensions should be selected such that each leaf is capable of being hardened to have a fully martensitic structure throughout the entire section. Suitable spring steel alloys include 55Si7, 60Si7, 65Si7, 50Cr4V2, and 60Cr4V2.: 6 Characteristics The two ends of a leaf spring usually are formed into round eyes or eyelets, through which a fastener connects each end of the spring to the vehicle frame or body. Some springs terminated in a concave end, called a spoon end (seldom used now), to carry a swiveling member instead. One eye is usually fixed translationally but allowed to pivot with the motion of the spring, whereas the other eye is fastened to a hinge mechanism that allows that end to pivot as well as undergo limited translational movement. A leaf spring can either be attached directly to the frame at both eyes or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm. The shackle takes up the tendency of the leaf spring to elongate when compressed and thus makes the suspension softer. The shackle provides some degree of flexibility to the leaf spring so that it does not fail when subjected to heavy loads. The axle is usually fastened to the middle of the spring by U-bolts.The leaf spring acts as a linkage to hold the axle in position and thus separate linkages are not necessary. The result is a suspension that is simple and strong. Inter-leaf friction dampens the spring's motion and reduces rebound, which, until shock absorbers were widely adopted, was a very significant advantage over helical springs. However, because the leaf spring is also serving to hold the axle in position, soft springs—i.e. springs with low spring constant—are not suitable. The consequent stiffness, in addition to inter-leaf friction, makes this type of suspension not particularly comfortable for the riders.
Operation and basic design:
Types There are a variety of leaf springs, usually employing the word "elliptical". "Elliptical" or "full elliptical" leaf springs, patented in 1804 by the British inventor Obadiah Elliott, referred to two circular arcs linked at their tips. This was joined to the frame at the top center of the upper arc, the bottom center was joined to the "live" suspension components, such as a solid front axle. Additional suspension components, such as trailing arms, would usually be needed for this design, but not for "semi-elliptical" leaf springs as used in the Hotchkiss drive. That employed the lower arc, hence its name. "Quarter-elliptic" springs often had the thickest part of the stack of leaves stuck into the rear end of the side pieces of a short ladder frame, with the free end attached to the differential, as in the Austin Seven of the 1920s. As an example of non-elliptic leaf springs, the Ford Model T had multiple leaf springs over its differential that were curved in the shape of a yoke. As a substitute for dampers (shock absorbers), some manufacturers laid non-metallic sheets in between the metal leaves, such as wood.
Operation and basic design:
Elliot's invention revolutionized carriage design and construction, removing the need for a heavy perch and making transportation over rough roadways faster, easier, and less expensive.
Operation and basic design:
Examples of leaf springs A more modern implementation is the parabolic leaf spring. This design is characterized by fewer leaves whose thickness varies from centre to ends following a parabolic curve. The intention of this design is to reduce inter-leaf friction, and therefore there is only contact between the leaves at the ends and at the centre, where the axle is connected. Spacers prevent contact at other points. Aside from weight-saving, the main advantage of parabolic springs is their greater flexibility, which translates into improved ride quality, which approaches that of coil springs; the trade-off is reduced load carrying capability. They are widely used on buses for improved comfort.
Operation and basic design:
A further development by the British GKN company and by Chevrolet, with the Corvette, among others, is the move to composite plastic leaf springs. Nevertheless, due to the lack of inter-leaf friction and other internal dampening effects, this type of spring requires more powerful dampers/shock absorbers.
Operation and basic design:
Typically when used in automobile suspension the leaf both supports an axle and locates/partially locates the axle. This can lead to handling issues (such as "axle tramp"), as the flexible nature of the spring makes precise control of the unsprung mass of the axle difficult. Some suspension designs use a Watts link (or a Panhard rod) and radius arms to locate the axle and do not have this drawback. Such designs can use softer springs, resulting in a better ride. Examples include the various rear suspensions of Austin-Healey 3000s and Fiat 128s.
History:
The earliest known leaf springs began appearing on carriages in France in the mid-17th century in the form of the two-part elbow spring (as the illustrated example from Lisbon), and later migrated to England and Germany, appearing on the carriages of the wealthy in those countries around 1750.: 1 Dr. Richard Lovell Edgeworth was awarded three gold medals by the Society of English Arts and Manufacturers in 1768 for demonstrating the superiority of sprung carriages. By 1796, William Felton's A Treatise on Carriages and Harness showed that leaf springs were being marketed regularly by the late 18th century carriage industry.: 1 Obadiah Elliot is credited with inventing the modern leaf spring with his 1804 patent on elliptical leaf springs, which brought him significant recognition and revenue, and engineers began studying leaf springs to develop improved designs and manufacturing processes. The mechanics and deflection of leaf springs were developed by Clark (1855), Franz Reuleaux (1861), and G.R. Henderson (1894).: 1 Improved steel rolling processes, process instruments, and spring steel alloys were developed during the latter half of the 19th century as well, making the manufacture of leaf springs more consistent and less expensive.: 2 Leaf springs were very common on automobiles until the 1970s when automobile manufacturers shifted primarily to front-wheel drive, and more sophisticated suspension designs were developed using coil springs instead. Today leaf springs are still used in heavy commercial vehicles such as vans and trucks, SUVs, and railway carriages. For heavy vehicles, they have the advantage of spreading the load more widely over the vehicle's chassis, whereas coil springs transfer it to a single point. Unlike coil springs, leaf springs also locate the rear axle, eliminating the need for trailing arms and a Panhard rod, thereby saving cost and weight in a simple live axle rear suspension. A further advantage of a leaf spring over a helical spring is that the end of the leaf spring may be guided along a definite path. In many late 1990s and early 2000s trucks, the leaf spring is connected to a Hinkle Beam ball joint.
History:
Leaf springs used in independent suspensions The leaf spring also has seen modern applications in cars. For example, the 1963 Chevrolet Corvette Sting Ray uses a transverse leaf spring for its independent rear suspension. Similarly, 2016 Volvo XC90 has a transverse leaf spring using composite materials for its rear suspension, similar in concept to the front suspension of the 1983 Corvette. This arrangement uses a straight leaf spring that is tightly secured to the chassis at the center; the ends of the spring are bolted to the wheel suspension, allowing the spring to work independently on each wheel. This suspension is smaller, flatter and lighter than a traditional setup.
Manufacturing process:
Multi-leaf springs are made as follows Pre heat treatment process: Shearing Taper Rolling Trimming End cutting & pressing Second Warping Scarfing and Eye rolling Nipping C’SKG punching Center hole drilling.
Manufacturing process:
Heat treatment processes: Heating for hardening Cambering Quenching Tempering Post- heat treatment processes: Rectification Side bend removing Bushing Reaming Clamp riveting Assembly and surface finishes: Shot peening Painting Assembling Scragging Marking and packing Heat treatment Heating for Hardening: Any metal, or alloy which can be hard drawn, or rolled to fairly high strength and retains sufficient ductility to form, may be used for springs, or any alloy which can be heat treated to high strength and good ductility before, or after forming may be used. For special spring properties such as good fatigue life, nonmagnetic characteristics, resistance to corrosion, elevated temperatures and drift require special considerations. leaves are heated to critical temperature in an Oil-fired hardening furnace. Usually temperature maintained is between 850°C and 950°C.
Manufacturing process:
Cambering: The top leaf is known as the master leaf. The eye is provided for attaching the spring with another machine member. The amount of bend that is given to the spring from the central line, passing through the eyes, is known as camber. The camber is provided so that even at the maximum load the deflected spring should not touch the machine member to which it is attached. The camber shown in the figure is known as positive camber. The central clamp is required to hold the leaves of the spring. Machine used for this operation is Hydraulic press. Leaves are bent to required radius using a press. All the leaves are tested for required radius using cambering gauges.
Manufacturing process:
Quenching : Hot bent leaves kept in tray and quenched in oil bath to get martensite structure. Martensite is the hardest form of steel crystalline structure. Martensite is formed in carbon steels by rapid cooling that is quenching of austenite form of iron. Machine used is conveyorized quench oil bath. Fire point of quenching oil is around 200°C and it is seen to that temperature of oil does not exceed 80°C. After quenching the structure of leaf spring becomes very hard and this property is not required. But this process is required to set the leaves to correct radius after cambering. To remove hardness tempering is done.
Manufacturing process:
Tempering: Tempering is a process of heat treating, which is used to increase the toughness. Quenched leaves are reheated to drop hardness to required level. Electric heated temperature furnace is used for this process. Hardness of the leaves is found out using Brinell hardness testing. This process is also done to relieve stresses. Temperature inside the machine is maintained between 540 and 680°C. Tempering process involves heating of leaves below their re-crystallization temperature and then cooling them using water or air.
Other uses:
By blacksmiths Because leaf springs are made of relatively high quality steel, they are a favorite material for blacksmiths. In countries such as India, Nepal, Bangladesh, Philippines, Myanmar and Pakistan, where traditional blacksmiths still produce a large amount of the country's tools, leaf springs from scrapped cars are frequently used to make knives, kukris, and other tools. They are also commonly used by amateur and hobbyist blacksmiths.
Other uses:
In trampolines Leaf springs have also replaced traditional coil springs in some trampolines (known as soft-edge trampolines), which improves safety for users and reduces risk of concussion. The leaf springs are spaced around the frame as 'legs' that branch from the base frame to suspend the jumping mat, providing flexibility and resilience.
Clutches The "diaphragm" common in automotive clutches is a type of leaf spring. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Kidney cancer**
Kidney cancer:
Kidney cancer, also known as renal cancer, is a group of cancers that starts in the kidney. Symptoms may include blood in the urine, lump in the abdomen, or back pain. Fever, weight loss, and tiredness may also occur. Complications can include spread to the lungs or brain.The main types of kidney cancer are renal cell cancer (RCC), transitional cell cancer (TCC), and Wilms' tumor. RCC makes up approximately 80% of kidney cancers, and TCC accounts for most of the rest. Risk factors for RCC and TCC include smoking, certain pain medications, previous bladder cancer, being overweight, high blood pressure, certain chemicals, and a family history. Risk factors for Wilms' tumor include a family history and certain genetic disorders such as WAGR syndrome. Diagnosis may be suspected based on symptoms, urine testing, and medical imaging. It is confirmed by tissue biopsy.Treatment may include surgery, radiation therapy, chemotherapy, immunotherapy, and targeted therapy. Kidney cancer newly affected about 403,300 people and resulted in 175,000 deaths globally in 2018. Onset is usually after the age of 45. Males are affected more often than females. The overall five-year survival rate is 75% in the United States, 71% in Canada, 70% in China, and 60% in Europe. For cancers that are confined to the kidney, the five-year survival rate is 93%, if it has spread to the surrounding lymph nodes it is 70%, and if it has spread widely, it is 12%. Kidney cancer has been identified as the 13th most common form of cancer, and is responsible for 2% of the world's cancer cases and deaths. The incidence of kidney cancer has continued to increase since 1930. Renal cancer is more commonly found in populations of urban areas than rural areas.
Signs and symptoms:
Early on, kidney masses do not typically cause any symptoms and are undetectable on physical examination. As kidney cancer becomes more advanced it classically results in blood in the urine, flank or back pain, and a mass. Other symptoms that are consistent with advanced disease include weight loss, fever, night sweats, palpable swollen lymph nodes in the neck, non-reducing varicocele, bone pain, continuous cough, and bilateral lower leg swelling.The classic triad of visible blood in the urine (hematuria), flank pain and palpable abdominal mass occurs in less than 15% of the cases. RCC may present with signs and symptoms caused by the substances the cancer cell produce (i.e. paraneoplastic syndromes).Paraneoplastic syndromes caused by kidney cancer can be broadly classified as endocrine and non-endocrine. Endocrine dysfunctions include increase in blood calcium levels (hypercalcemia), high blood pressure (hypertension), increased red bloods (polycythemia), liver dysfunction, milky nipple discharge unrelated normal breast-feeding (galactorrhea), and Cushing's syndrome. Non-endocrine dysfunctions include deposition of protein in tissue (amyloidosis), decrease in hemoglobin or red blood cells (anemia), disorders of nerves, muscles (neuromyopathies), blood vessels (vasculopathy) and blood clotting mechanisms (coagulopathy).
Causes:
Factors that increase the risk of kidney cancer include smoking, high blood pressure, obesity, faulty genes, a family history of kidney cancer, having kidney disease that needs dialysis, being infected with hepatitis C, and previous treatment for testicular cancer or cervical cancer.There are also other possible risk factors such as kidney stones being investigated.About 25-30% of kidney cancer is attributed to smoking. Smokers have a 1.3 times higher risk of developing kidney cancer compared to non-smokers. Moreover, there is a dose-dependent increased risk of cancer development. Men who smoke more than 20 cigarettes per day have twice the risk. Likewise, women who smoke more than 20 cigarettes per day have 1.5 times the risk of non-smokers. After 10 years of smoking cessation a substantial reduction is seen in the risk of developing kidney cancer.
Diagnosis:
Due to the increase in ultrasound and CT imaging for nonspecific abdominal complaints, kidney masses are frequently incidentally diagnosed on medical imaging. More than 60% of renal cell carcinoma (the most common type of kidney cancer), are diagnosed incidentally by abdominal imaging for nonspecific abdominal complaints.Kidney masses can be classified by the nature of the cells in the growth, or by its appearance on radiography. The term cancer refers to a malignant tumor, which is an uncontrolled growth of abnormal cells. However, kidney masses can be due to growth of normal tissue (benign), inflammatory (a reaction of the immune system), or vascular (cells of the blood vessels).
Diagnosis:
Medical imaging Since there is a large differential diagnosis for a kidney tumor, the first step is to characterize the mass with medical imaging to assess its likelihood of being benign or malignant. Ultrasonography is sometimes used to evaluate a suspected kidney mass, as it can characterize cystic and solid kidney masses without radiation exposure and at relative low cost. Radiologically tumors are grouped based on appearance into simple cystic, complex cystic, or solid. The most important differentiating feature of a cancerous and non-cancerous tumor on imaging is enhancement. Simple cysts, which are defined by strict criteria are safe to be monitored if the person does not have any symptoms. However, all masses that are not clearly simple cysts should be further evaluated and confirmed by alternate imaging techniques.Computed tomography (CT) of the abdomen administered with and without IV contrast is the ideal imaging to diagnose and stage kidney cancer. There is tentative evidence that iodinated contrast agents may cause worsening of kidney function in people with chronic kidney disease (CKD) with a glomerular filtration rate (GFR) less than 45ml/min/1.73m2 and should therefore be given cautiously in this group.Abdominal magnetic resonance imaging (MRI) is an alternative imaging method that can be used to characterize and stage a kidney mass. It may be suggested if contrast material cannot be given. MRI can also evaluate the inferior vena cava if the mass is suspected to extend outside the kidney.Since the lungs are the most common organ for kidney cancer to spread to, a chest X-ray or CT scan may be ordered based on the person's risk for metastatic disease.
Diagnosis:
Histopathologic classification The most common type of kidney malignancy is renal cell carcinoma, which is thought to originate from cells in the proximal convoluted tubule of the nephron. Another type of kidney cancer although less common, is transitional cell cancer (TCC) or urothelial carcinoma of the renal pelvis. The renal pelvis is the part of the kidney that collects urine and drains it into a tube called the ureter. The cells that line the renal pelvis are called transitional cells, and are also sometimes called urothelial cells. The transitional/urothelial cells in the renal pelvis are the same type of cells that line the ureter and bladder. For this reason TCC of the renal pelvis is distinct from RCC and is thought to behave more like bladder cancer. Other rare types of kidney cancers that can arise from the urothelial cells of the renal pelvis are squamous cell carcinoma and adenocarcinoma.Other causes of kidney cancer include the following: Sarcoma- for example leiomyosarcoma, liposarcoma, angiosarcoma, clear-cell sarcoma and rhabdomyosarcoma are types of sarcomas that have occurred in the kidney Metastatic tumor from distant organ Lymphoma Wilms tumor- an embryonic tumor that is the most common type of kidney cancer in children Carcinoid tumor of the renal pelvis Carcinosarcoma Inverted urothelial papilloma- was traditionally regarded as a benign growth. However, there may be an increased risk for recurrence and transformation to TCC.In children, Wilms tumor is the most common type of kidney cancer. Mesoblastic nephroma, although rare, also typically presents in childhood.
Diagnosis:
Renal cell carcinoma has been further divided into sub-types based on histological features and genetic abnormalities. The 2004 WHO Classification of the Renal Tumors of the Adults describes these categories: Clear cell RCC Multilocular clear cell RCC Papillary RCC Chromophobe RCC Carcinoma of the collecting ducts of Bellini Renal medullary carcinoma Xp11 translocation carcinomas Carcinoma associated with neuroblastoma Mucinous tubular and spindle cell carcinoma Mixed epithelial stromal tumorTumors that are considered benign include angiomyolipoma, oncocytoma, reninoma (juxtaglomerular cell tumor), and renal adenoma.
Diagnosis:
Immunohistochemistry Laboratory studies People with suspected kidney cancer should also have their kidney function evaluated to help determine treatment options. Blood tests to determine kidney function include a comprehensive metabolic panel (CMP), a complete blood count (CBC). In addition, these tests help understand the overall health of the person, which can be affected by metastatic disease (disease that is outside of the kidney). For example, liver or bone involvement could result in abnormal liver enzymes, electrolyte abnormalities, or anemia. A urine sample should also be collected for urinalysis.
Diagnosis:
Biopsy The utility of renal mass biopsy (RMB) lies in that it can confirm malignancy with reliability, can direct therapy based on diagnosis, and can provide drainage.Once imaging has been completed, renal mass biopsy should be considered if there is a high likelihood that the mass is hematologic, metastatic, inflammatory, or infectious. These types of lesions would not be managed surgically, differing from cancer originating from the kidney. Cancer originating outside the kidney and lymphoma are managed systemically.RMB can accurately diagnose malignancy, however, it cannot reliably diagnose benign disease. In other words, if the biopsy shows cancer, there is a 99.8% chance that kidney cancer is present (Positive Predictive Value= 99.8%). A negative biopsy does not rule out a diagnosis of cancer.
Diagnosis:
Staging Staging is the process that helps determine the extent and spread of the disease. Renal cell carcinoma is the only type of kidney cancer that can be staged. The first step of staging follows the TNM staging system proposed by the Union International Contre le Cancer that is widely used among cancers in other organs. The TNM staging system classifies the primary tumor (T), lymph nodes (N) and distant metastasis (M) of the disease. The American Joint Committee on Cancer (AJCC) published a Cancer Staging Manual revision in 2010 that describes the values of TMN for renal cell carcinoma.Lymph node involvement is classified as either regional lymph node metastasis (N1), or no involvement (N0). Similarly, M1 describes distant metastasis, while M0 describes no distant metastasis.The primary tumor of renal cell carcinoma is categorized in the table below, as according to the AJCC 8th Edition Cancer Staging Manual: The lungs are the most common site for metastasis, with other common sites including bone, brain, liver, adrenal gland and distant lymph nodes.
Treatment:
Treatment for kidney cancer depends on the type and stage of the disease. Surgery is the most common treatment as kidney cancer does not often respond to chemotherapy and radiotherapy. Surgical complexity can be estimated by the RENAL Nephrometry Scoring System. If the cancer has not spread it will usually be removed by surgery. In some cases this involves removing the whole kidney however most tumors are amenable to partial removal to eradicate the tumor and preserve the remaining normal portion of the kidney. Surgery is not always possible – for example, the patient may have other medical conditions that prevent it, or the cancer may have spread around the body and doctors may not be able to remove it. If the cancer cannot be treated with surgery other techniques such as freezing the tumour or treating it with high temperatures may be used. However, these are not yet used as standard treatments for kidney cancer. Recently, evidence stemming from the KEYNOTE-564 study has shed light on the potential use of systemic therapy in the adjuvant setting, with promising results. Patients exhibiting specific clear cell RCC tumor characteristics and having undergone treatment with Pembrolizumab for 17 cycles (around 1 year) had significant improvement in disease-free survival. However, the study has yet to yield conclusive findings in relation to overall survival. Other treatment options include biological therapies such as everolimus, torisel, nexavar, sutent, and axitinib, the use of immunotherapy including interferon and interleukin-2. Immunotherapy is successful in 10 to 15% of people. Sunitinib is the current standard of care in the adjuvant setting along with pazopanib; these treatments are often followed by everolimus, axitinib, and sorafenib. Immune checkpoint inhibitors are also in trials for kidney cancer, and some have gained approval for medical use.In the second line setting, nivolumab demonstrated an overall survival advantage in advanced clear renal cell carcinoma over everolimus in 2015 and was approved by the FDA. Cabozantinib also demonstrated an overall survival benefit over everolimus and was approved by the FDA as a second-line treatment in 2016. Lenvatinib in combination with everolimus was approved in 2016 for patients who have had exactly one prior line of angiogenic therapy.In Wilms' tumor, chemotherapy, radiotherapy and surgery are the accepted treatments, depending on the stage of the disease when it is diagnosed.
Treatment:
Children The majority of kidney cancers reported in children are Wilms' tumors. These tumors can begin to grow when a fetus is still developing in the uterus, and may not cause problems until the child is a few years old. Wilms' tumor is most common in children under the age of 5, but can rarely be diagnosed in older children or in adults. It is still not clear what causes most Wilms' tumors. The most common symptoms are swelling of the abdomen and blood in the urine.
Epidemiology:
Around 208,500 new cases of kidney cancer are diagnosed in the world each year, accounting for just under 2% of all cancers. The highest rates are recorded in North America and the lowest rates in Asia and Africa.Lifestyle risk factors Certain lifestyle factors have been associated with the development of renal cancer, although not all of them can be considered definitive causes. These include smoking, chemical carcinogens, radiation, viruses, diet and obesity, hypertension, diuretics, and alcohol consumption. Only a small percentage of kidney cancer cases have been linked to genetic factors. With obesity listed as one of the risk factors, daily physical activity and engaging in a healthy diet is proven to lower the rates of developing kidney cancer in the future.Age The incidence rate of renal cancer increases with the age of an individual, with 75 being the approximate age of the peak incidence rate, as of 2018. However, nearly one half of all cases are diagnosed before the age of 65. In both male and female children, renal tumors represent 2% to 6% of kidney cancer, with Wilms' tumor being the most common.
Epidemiology:
Sex The incidence of kidney cancer is two times greater in men than in women, and this is thought to be due to biological differences. Mortality rates typically decrease more rapidly in women compared to men.International variations Incidence rates of kidney cancer can vary throughout the world. As of 2018, Czech Republic and Lithuania have the highest incidence rate of kidney cancer worldwide, with an age-standardized rate of 21.9/100,000 in males (Czech Republic) and 18.7/100,000 in males (Lithuania.) China, Thailand, and African countries (low-risk countries) have an incidence rate that is less than 2/100,000.Since the early 2000s, Austria and Poland have been the only countries to report a decrease in kidney cancer rates.Diagnosis access bias plays a large role in the epidemiology of kidney cancer. Differences in kidney cancer diagnosis across regions are likely due to differences in healthcare access, rather than a population's biological factors. Discrepancies in kidney cancer diagnosis has most likely led to the underrepresentation of mortality and incidence in low income countries. Race Race and ethnicity may be a factor in the distribution of kidney cancer around the United States. There are higher incidence rates in Black men and Hispanics, an average rate for American Indians, and low rates in Asians in the United States. Black people with kidney cancer have lower mortality rates than Caucasians in the United States.Screening Accessibility for cancer screening is not very common due to high expenses. Improving cancer registries can improve care to those who have kidney cancer as well as decreasing the incidence and death rates. Safe and dependable treatment is key with the screening and treatment, which is not always the case in many developing nations.
Epidemiology:
United States The United States' NIH estimates for 2013 around 64,770 new cases of kidney cancer and 13,570 deaths from the disease.The incidence of kidney cancer is also increasing in the United States. This is thought to be a real increase, not only due to changes in the way the disease is diagnosed.
Europe The most recent estimates of incidence of kidney cancer suggest that there are 63,300 new cases annually in the EU25. In Europe, kidney cancer accounts for nearly 3% of all cancer cases.
Kidney cancer is the eighth most common cancer in the UK (around 10,100 people were diagnosed with the disease in 2011), and it is the fourteenth most common cause of cancer death (around 4,300 people died in 2012). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Sinc numerical methods**
Sinc numerical methods:
In numerical analysis and applied mathematics, sinc numerical methods are numerical techniques for finding approximate solutions of partial differential equations and integral equations based on the translates of sinc function and Cardinal function C(f,h) which is an expansion of f defined by sinc (xh−k) where the step size h>0 and where the sinc function is defined by sinc sin (πx)πx Sinc approximation methods excel for problems whose solutions may have singularities, or infinite domains, or boundary layers.
Sinc numerical methods:
The truncated Sinc expansion of f is defined by the following series: sinc (xh−k)
Sinc numerical methods cover:
function approximation, approximation of derivatives, approximate definite and indefinite integration, approximate solution of initial and boundary value ordinary differential equation (ODE) problems, approximation and inversion of Fourier and Laplace transforms, approximation of Hilbert transforms, approximation of definite and indefinite convolution, approximate solution of partial differential equations, approximate solution of integral equations, construction of conformal maps.Indeed, Sinc are ubiquitous for approximating every operation of calculus In the standard setup of the sinc numerical methods, the errors (in big O notation) are known to be O(e−cn) with some c>0, where n is the number of nodes or bases used in the methods. However, Sugihara has recently found that the errors in the Sinc numerical methods based on double exponential transformation are ln n) with some k>0, in a setup that is also meaningful both theoretically and practically and are found to be best possible in a certain mathematical sense.
Reading:
Stenger, Frank (2011). Handbook of Sinc Numerical Methods. Boca Raton, Florida: CRC Press. ISBN 9781439821596.
Lund, John; Bowers, Kenneth (1992). Sinc Methods for Quadrature and Differential Equations. Philadelphia: Society for Industrial and Applied Mathematics (SIAM). ISBN 9780898712988. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Grid cell topology**
Grid cell topology:
The grid cell topology is studied in digital topology as part of the theoretical basis for (low-level) algorithms in computer image analysis or computer graphics. The elements of the n-dimensional grid cell topology (n ≥ 1) are all n-dimensional grid cubes and their k-dimensional faces ( for 0 ≤ k ≤ n−1); between these a partial order A ≤ B is defined if A is a subset of B (and thus also dim(A) ≤ dim(B)). The grid cell topology is the Alexandrov topology (open sets are up-sets) with respect to this partial order. (See also poset topology.) Alexandrov and Hopf first introduced the grid cell topology, for the two-dimensional case, within an exercise in their text Topologie I (1935).
Grid cell topology:
A recursive method to obtain n-dimensional grid cells and an intuitive definition for grid cell manifolds can be found in Chen, 2004. It is related to digital manifolds. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Traffic engineering (transportation)**
Traffic engineering (transportation):
Traffic engineering is a branch of civil engineering that uses engineering techniques to achieve the safe and efficient movement of people and goods on roadways. It focuses mainly on research for safe and efficient traffic flow, such as road geometry, sidewalks and crosswalks, cycling infrastructure, traffic signs, road surface markings and traffic lights. Traffic engineering deals with the functional part of transportation system, except the infrastructures provided.
Traffic engineering (transportation):
Traffic engineering is closely associated with other disciplines: Transport engineering Pavement engineering Bicycle transportation engineering Highway engineering Transportation planning Urban planning Human factors engineeringTypical traffic engineering projects involve designing traffic control device installations and modifications, including traffic signals, signs, and pavement markings. Examples of Engineering Plans include pole engineering analysis and Storm Water Prevention Programs (SWPP). However, traffic engineers also consider traffic safety by investigating locations with high crash rates and developing countermeasures to reduce crashes. Traffic flow management can be short-term (preparing construction traffic control plans, including detour plans for pedestrian and vehicular traffic) or long-term (estimating the impacts of proposed commercial/residential developments on traffic patterns). Increasingly, traffic problems are being addressed by developing systems for intelligent transportation systems, often in conjunction with other engineering disciplines, such as computer engineering and electrical engineering.
Traffic systems:
Traditionally, road improvements have consisted mainly of building additional infrastructure. However, dynamic elements are now being introduced into road traffic management. Dynamic elements have long been used in rail transport. These include sensors to measure traffic flows and automatic, interconnected, guidance systems to manage traffic (for example, traffic signs which open a lane in different directions depending on the time of day). Also, traffic flow and speed sensors are used to detect problems and alert operators, so that the cause of the congestion can be determined, and measures can be taken to minimize delays. These systems are collectively called intelligent transportation systems.
Traffic systems:
Lane flow equation The relationship between lane flow (Q, vehicles per hour), space mean speed (V, kilometers per hour) and density (K, vehicles per kilometer) is Q=KV Observation on limited access facilities suggests that up to a maximum flow, speed does not decline while density increases. However, above a critical threshold (BP, breakpoint), increased density reduces speed. Additionally, beyond a further threshold, increased density reduces flow as well.
Traffic systems:
Therefore, speeds and lane flows at bottlenecks can be kept high during peak periods by managing traffic density using devices that limit the rate at which vehicles can enter the highway. Ramp meters, signals on entrance ramps that control the rate at which vehicles are allowed to enter the mainline facility, provide this function (at the expense of increased delay for those waiting at the ramps).
Highway safety:
Highway safety engineering is a branch of traffic engineering that deals with reducing the frequency and severity of crashes. It uses physics and vehicle dynamics, as well as road user psychology and human factors engineering, to reduce the influence of factors that contribute to crashes. A well-drafted Traffic Control Plan (TCP) is critical to any job involving roadway work. A properly-prepared TCP will specify equipment, signage, placement, and personnel.A typical traffic safety investigation follows these steps: 1. Identify and prioritize investigation locations. Locations are selected by looking for sites with higher than average crash rates, and to address citizen complaints.2. Gather data. This includes obtaining police reports of crashes, observing road user behavior, and collecting information on traffic signs, road surface markings, traffic lights and road geometry.3. Analyze data. Look for collisions patterns or road conditions that may be contributing to the problem.4. Identify possible countermeasures to reduce the severity or frequency of crashes.
Highway safety:
• Evaluate cost/benefit ratios of the alternatives • Consider whether a proposed improvement will solve the problem, or cause "crash migration." For example, preventing left turns at one intersection may eliminate left turn crashes at that location, only to increase them a block away.
• Are any disadvantages of proposed improvements likely to be worse than the problem you are trying to solve?5. Implement improvements.6. Evaluate results. Usually, this occurs some time after the implementation. Have the severity and frequency of crashes been reduced to an acceptable level? If not, return to step 2.
Traffic Engineering Societies:
Institute of Transportation Engineers (ITE), an international membership society of transportation engineers, founded in 1930.Transportation & Development Institute (T&DI) of the American Society of Civil Engineers (ASCE) | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Power assembly**
Power assembly:
The term power assembly refers to an Electro-Motive Diesel (EMD) engine sub-assembly designed to be "easily" removed and replaced in order to restore engine performance lost to wear or engine failure. Typical of heavy-duty internal combustion engines used in industrial applications, EMD engines are designed to allow the cylinder liners, pistons, piston rings and connecting rods to be replaced at overhaul without removing the entire engine assembly from its application location. This increases engine value, reduces downtime and allows the engine to be returned to true new engine performance. Other terms such as cylinder pack, liner pack, cylinder assembly and cylinder kit are used in the engine industry to describe similar assemblies. In the large-engine industry, the term "power assembly" has also become generic and is often used to refer to the assemblies used in non-EMD engines where "power pack" may be the preferred term, although both terms are functionally the same.
Power assembly:
Because of the size and weight of the engine assembly and the difficulties of removing and transporting them for repair, they are typically serviced on-site in stationary applications and in the ship or locomotive in transportation applications. Designing the engine for "easy" service is done out of necessity rather than the desire to increase engine serviceability. Power assemblies are large and heavy and overhead lifting equipment sufficient to lift the fixture and assembly are required.
Power assembly:
An EMD power assembly consists of the following components: Cylinder head assembly (including valves, springs, keepers etc.) less fuel system components Cylinder liner Piston and piston rings Piston carrier Connecting rodIn an EMD diesel engine, since two power assemblies share a common connecting-rod journal, and since the power assemblies are directly opposite each other rather than staggered as in a typical V-type engine, two different power assemblies are required in a single engine. The difference between the two assemblies is in the connecting rods. One connecting rod "big end" has to fit inside that of its companion rod and the two types are referred to as "blade rods" and "fork rods". The "fork rod" is logically the "master" as only it has a "rod cap", in this specific case referred to as a "basket", whereas the "blade rod" is logically the "slave" as its "big toe" is designed to fit completely within, and is guided by, and is retained by the "fork", and both are retained by the single "basket".
Power assembly:
Several situations can require power assembly replacement. Most are due to failure within the power assembly itself such as a dropped valve, broken piston or internal coolant leak. Less common are replacements to repair catastrophic failures such as broken connecting rods or a "hydro-locked" power assembly that has been broken or knocked out of the cylinder block when the cylinder filled with coolant during engine operation and the inability of the piston to compress the liquid caused catastrophic failure. Complete power assembly replacements, where all of the assemblies in an engine are replaced, are least common and are normally done as part of a comprehensive engine overhaul.
Power assembly:
In a normal in-service power assembly replacement situation, the replacement will follow an inspection of the engine specifically performed to find internal engine failures. With the engine crankcase access and cylinder block airbox covers removed, a visual inspection of the engine's rotating and reciprocating assemblies can be performed. The use of a fiber optic endoscope (flexible borescope) may facilitate this inspection and evaluation, but this is not a requirement, nor is it a part of EMD's maintenance program.
Power assembly:
The engine airbox covers (the upper covers observed on the side of an EMD engine - they cover the "airbox" that allows air to flow through the cylinder block to the power assemblies) are removed to allow visual inspection of the inside of the cylinder liners and the piston crowns, skirts and rings. The crankcase access covers (the lower covers observed on the side of an EMD engine) are also removed to inspect for coolant leakage, damaged components and excessive wear. A proper inspection requires filling and pressurizing the cooling system to check for leakage from the power assemblies.
Power assembly:
To inspect the engine, it can be manually "barred over" with a lever, but manual engine rotation is slow and inefficient. In some applications manually barring the engine over can be difficult or impossible. The preferred tool for engine rotation is an electrically powered, hydraulically operated "turning jack". The turning jack uses a hydraulic cylinder and ram assembly that automatically advances to engage a hole in the flywheel. When the ram reaches its limit, it automatically retracts and advances again to engage another hole. The engine is then progressively rotated through its cycle and can be rotated in either direction by installing the jack on either side of the engine. Not only is a turning jack faster and more efficient, it is also safer since there is no risk of a barring lever coming loose and causing injury or damage. Also, with a turning jack, there is no need for the mechanic to be in physical contact with the engine at any point during the inspection process.
Power assembly:
A turning jack also allows a complete top deck and crankcase inspection to be performed by one mechanic in minutes, and inspecting the engine with the components in motion produces a better inspection. Rocker arm rollers can be inspected for proper rotation, potential valvetrain problems such as insufficient or excessive clearance can be observed, piston ring movement in the ring grooves indicating excessive groove wear can be observed, broken valvesprings can be more easily seen, and so on. A turning jack also allows the mechanic to observe the flywheel timing marks while the engine is rotating to time the engine properly for maintenance or post-repair engine valve-train and fuel-system adjustments.
Power assembly:
Claims of power assembly replacement being possible with "ordinary tools" in a "few hours" are subjective, as the tools necessary are hardly "ordinary" in typical mechanic shops and actual repair times can vary widely depending on the situation. At the minimum, large sockets and high-capacity torque multipliers are necessary to enable the large nuts retaining the hold-downs to be removed and retorqued to proper specifications. Various other special tools, while not strictly required, make the job much easier. Additionally, there are special tools required for adjustment of the fuel system after assembly replacement.
Power assembly:
As far as repair time goes, power assembly replacement is typically performed by at least two mechanics so the labor involved is at least twice the repair time required. If the engine comes in for inspection or repair "hot", the unit may need to cool for several hours before repairs can begin. If parts are not readily available, the delays will increase. Typically, for a power assembly replacement in an engine cool enough to work on and with the proper tools and necessary parts readily at hand, two mechanics can replace a power assembly properly and safely in a 4-hour period. Rarely are major repairs involving expensive engines and components and significant safety hazards rushed to create "efficiency" at the expense of safety and reliability.
Power assembly:
The quality and layout of the work area also has a big effect on the time required and the quality of the work. Proper equipment and tools make the job "easy". Poor working conditions and having to make do without the appropriate tools and equipment can make the replacement process a nightmare. The aforementioned "barring over" with a lever versus having a turning jack is a good example of being properly equipped. A properly equipped repair shop for mobile equipment (locomotives) or individual engines (rebuild/overhaul shop) or the area where stationary engines are permanently installed (marine applications where the engine cannot be practically removed for service or electrical power plants, etc.) will be equipped with sufficient overhead lifting equipment to allow the assemblies to be safely and efficiently handled, removed and installed.
Power assembly:
Although the components are large and heavy and specialized tools are required, the replacement process is straightforward and simple. The engine coolant is drained, the test valve "snifter" is removed, the rocker arm assembly and fuel system components are removed, the connecting rod is disconnected from the crankshaft, the power assembly hold-downs (commonly called "crabs") are removed, the cooling system plumbing is disconnected, piston cooling tube is removed, the lifting fixture is installed and the power assembly is lifted out of the cylinder block. The process is reversed to install the replacement power assembly.
Power assembly:
Following installation of the replacement assembly, all hardware is torqued to specs, the cooling system is refilled, the engine crankshaft is properly timed to allow the valves and fuel injector of the new power assembly to be adjusted, the valve train and fuel injection system is adjusted using appropriate gauges, the fuel system is primed and the engine is started and checked for proper operation and leaks within the cooling system, if any, are identified. As in any other situation where an engine is rebuilt, there is a "break-in" period for replacement power assemblies that should include operating the engine at varying speeds and loads for a specified period of time to seat the cylinder rings before the engine is placed into normal service. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Mortran**
Mortran:
Mortran (More Fortran) is an extension of the Fortran programming language used for scientific computation. It introduces syntax changes, including the use of semicolons to end statements, in order to improve readability and flexibility. Mortran code is macro-processed into Fortran code for compilation.
Mortran:
Example: Note that Mortran, like many preprocessors, does not make a complete analysis of the Fortran source and, like many preprocessors, may not always make its assumptions/requirements explicit. Consider, for example, Mortran multiple assignment. From the Mortran User Guide: produces the following FORTRAN statements: In this example, the produced Fortran implements the multiple assignment correctly only if X is not aliased to I or to A(I,K), assuming the multiple assignment semantics are left to right.
Mortran:
The MORTRAN2 processor is written in ANSI standard Fortran 66, with the only extension the ability to assign and compare character data stored in INTEGER variables. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Caffeine dehydrogenase**
Caffeine dehydrogenase:
Caffeine dehydrogenase, commonly referred to in scientific literature as caffeine oxidase (EC 1.17.5.2), is an enzyme with the systematic name caffeine:ubiquinone oxidoreductase. The enzyme is most well known for its ability to directly oxidize caffeine, a type of methylxanthine, to trimethyluric acid. Caffeine dehydrogenase can be found in bacterium Pseudomonas sp. CBB1 and in several species within the genera Alcaligenes, Rhodococcus, and Klebsiella.
Structure:
Caffeine dehydrogenase found in Pseudomonas sp. CBB1 is a heterotrimer with a αβγ structure and is encoded by the gene cdhA. The alpha subunit is the largest of the three, and the gamma subunit is the smallest. The molecular weights of the alpha, beta, and gamma subunits are 90.0 kD, 40.0 kD, and 20.0 kD respectively. However, caffeine dehydrogenase has also been found as a monomeric structure in Alcaligenes sp. strain CF8 (65 kDa) and a Rhodococcus sp.-Klebsiella sp. mixed-culture consortium. The heterotrimer is noted as being similar to the xanthine dehydrogenase found in Veillonella atypica.
Reaction:
In comparison to N-demethylases, another class of caffeine-degrading enzymes, caffeine dehydrogenase does not require the use of oxygen, NAD, or NADP as electron acceptors. Instead, caffeine dehydrogenase uses dichlorophenol, indophenol, coenzyme Q0, and cytochrome c as electron acceptors. Caffeine dehydrogenase has been noted as being more stable as well.
Reaction:
Caffeine dehydrogenase is responsible for catalyzing the oxidation of caffeine directly into trimethyluric acid, and the enzyme uses coenzyme Q0, also known as ubiquinone, as an electron acceptor. This is done by incorporating an oxygen atom from a water molecule into the C-8 position, and the overall reaction can be seen in the following chemical reaction: The enzyme is specific for caffeine, less active on theobromine, and has no activity on xanthine. The product is stoichiometrically produced from caffeine at a 1:1 molar ratio, and there was no hydrogen peroxide byproduct. Enzyme activity is optimal at pH 7.0 in 50 mM potassium phosphate buffer, and activity increased linearly from 298 K to 339 K.
Biological function:
Trimethyluric acid can enter the purine catabolic pathway and further break down into other useful compounds. Trimethyluric acid has been reported to break down further into 3, 6, 8-trimethylallantoin by resting cells in a Rhodococcus and Klebsiella mixed culture.
Industrial significance:
Caffeine (1,3,7-trimethylxanthine), the substrate in the above reaction, is a purine alkaloid found in a variety of plant species, such as coffee, cacao, cola, and tea leaves. Caffeine has also been used as a cardiac, neurological, and respiratory stimulant. Because of its prevalence in the modern world in the form of beverages, food, and medicine, caffeine has become one of the world's major agro-industrial wastes. Thus, caffeine has become more noticeable in surface water, groundwater, and waste water effluents all over the world. In addition to being an addictive substance, it has also been shown to lead to adverse health effects, such as irregular sleeping patterns, increase in blood pressure, palpitations, and anxiety.Decaffeination has been traditionally recommended to reduce caffeine content in food and beverages, but to perform decaffeination by physio-chemical treatments is expensive and can produce other waste that may require further treatment. Thus, microbial bioprocessing has begun to appear more attractive, with bacteria that are capable of metabolizing caffeine being considered. Specifically, bacteria containing caffeine dehydrogenase have been seen as helpful in treating caffeine in agro-industrial wastes of coffee pulps and husks, which can then be used to feed farm animals. In addition, the caffeine dehydrogenase found in Alcaligenes species CF8 may be useful in waste treatment and biosensor development.Caffeine dehydrogenase, when in the presence of a tetrazolium dye, has been shown to be suitable for detecting caffeine in coffee, soda, and milk due to its high specificity for caffeine. Thus, been used to estimate caffeine levels in pharmaceuticals. However, it has been noted that caffeine dehydrogenase would not be useful in the recovery of methylxanthine intermediates that hold pharmaceutical value since the reaction is only a single step. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Burr (cutter)**
Burr (cutter):
Burrs or burs (sometimes called rotary files) are small cutting tools; not to be confused with small pieces of metal formed from cutting metal, used in die grinders, rotary tools, or dental drills. The name may be considered appropriate when their small-sized head (3 mm diameter shaft) is compared to a bur (fruit seed with hooks) or their teeth are compared to a metal burr.
Description:
Burrs are a rotary analog to files that cut linearly (hence their alternate name, rotary files). They are also in many ways comparable to endmills and router bits; a distinction is that the latter usually have their toolpath controlled by the machine, whereas burrs are often used freehand. However, there is substantial overlap in the use and toolpath control of these various classes of cutters, and e outcomes accomplished with them. For example, endmills can be used in routers, and burrs can be used like endmills in milling by CNC or manual machine tools. These are often used in CNC machining centers for removing burrs (the small flakes of metal) after a machining process.
Description:
Burrs are spun quickly to maintain the ideal surface speed and cutting conditions (thousands or tens of thousands of RPM; often the top speed available on a given spindle). Because they are constructed of tungsten carbide, the cutters in the image can operate at higher speeds than comparable "HSS" cutters while still maintaining their cutting edges.
Description:
Because the cutting edges of burrs are so small, they can often be touched when spinning by a finger without cutting the skin, which flexes out of the way, although it would not be safe to pinch or grip them from two sides. Hard metal or ceramic workpieces cannot flex beyond the cutting edges, so the tools remove material from them. This characteristic makes burrs suitable for use in dentistry, as the tool will grind the hard enamel of teeth, yet leaves soft mouth tissues unharmed if the tool should unintentionally touch them. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Pencil board**
Pencil board:
Shitajiki (下敷き, lit. "under-sheet") is a Japanese word for various types of materials placed under a sheet of paper for writing, either to prevent marking on the sheets below or to provide a better surface for writing. They are usually referred to as pencil boards in English.
Pencil board:
Shitajiki for handwriting are generally made of plastic about 1 to 2 mm in thickness, making them flexible but still durable. Typically, they are B5 sized (slightly smaller than U.S. letter size), although other sizes are also available (typically A4 or A5). Shitajiki for calligraphy are typically made of dark (blue or black) felt, and are available in a variety of sizes.
Pencil board:
Merchandised shitajiki are very common, featuring images of everything from tourist attractions and celebrities to anime and manga characters. Most shitajiki designs only go through one print run, making them highly collectible and often difficult to acquire. Collecting shitajiki is a hobby for many anime and manga enthusiasts. As collectibles, shitajiki are also often used for decoration or other ornamental purposes. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Ultrasonic hearing**
Ultrasonic hearing:
Ultrasonic hearing is a recognised auditory effect which allows humans to perceive sounds of a much higher frequency than would ordinarily be audible using the inner ear, usually by stimulation of the base of the cochlea through bone conduction. Normal human hearing is recognised as having an upper bound of 15–28 kHz, depending on the person.
Ultrasonic hearing:
Ultrasonic sinusoids as high as 120 kHz have been reported as successfully perceived. Two competing theories are proposed to explain this effect. The first asserts that ultrasonic sounds excite the inner hair cells of the cochlea basal turn, which are responsive to high frequency sounds. The second proposes that ultrasonic signals resonate the brain and are modulated down to frequencies that the cochlea can then detect.Researchers Tsutomu Oohashi et al. have coined the term hypersonic effect to describe the results of their controversial study supporting audibility of ultrasonics.By modulating speech signals onto an ultrasonic carrier, intelligible speech has also been perceived with a high degree of clarity, especially in areas of high ambient noise. Deatherage states that what humans experience as ultrasonic perception may have been a necessary precursor in the evolution of echolocation in marine mammals. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**NuMI**
NuMI:
Neutrinos at the Main Injector, or NuMI, is a project at Fermilab which creates an intense beam of neutrinos aimed towards the Far Detector facility near Ash River, Minnesota for use by several particle detectors. As of June 2010, the MINOS, MINERνA and NOνA experiments use the NuMI beam.
Neutrino production:
The first step in the production of the NuMI beam is to direct a beam of protons from Fermilab's Main Injector onto a carbon target. Interactions of the proton beam in the target produce mesons, primarily pions and kaons, which are focused toward the beam axis by two magnetic horns. The mesons then decay into muons and neutrinos during their flight through a long decay tunnel. A hadron absorber downstream of the decay tunnel removes the remaining protons and mesons from the beam. The muons are absorbed by the subsequent earth shield, while the neutrinos continue through it to the MINERνA, MINOS, and NOvA near detectors on-site at Fermilab. The neutrinos then travel through the Earth to the MINOS far detector cavern in the Soudan Mine 735 km away and the NOvA far detector 810 km away at Ash River, MN, then onwards into space.
Naming:
Because of the close relationship between NuMI and the MINOS experiment, MINOS is sometimes conflated with NuMI. For instance, the MINOS webpage was at www-numi.fnal.gov instead of www-minos.fnal.gov. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Seminormal subgroup**
Seminormal subgroup:
In mathematics, in the field of group theory, a subgroup A of a group G is termed seminormal if there is a subgroup B such that AB=G , and for any proper subgroup C of B , AC is a proper subgroup of G This definition of seminormal subgroups is due to Xiang Ying Su.Every normal subgroup is seminormal. For finite groups, every quasinormal subgroup is seminormal. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Ranger Cookie**
Ranger Cookie:
A Ranger Cookie is an improvised confection created through the use of MRE condiments. The cookie is created by baking sugar and coffee creamer over a heat source. Depending on the MRE variant, other ingredients can be added to the cookie. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**SteamOS**
SteamOS:
SteamOS is a Linux distribution developed by Valve. It incorporates Valve's popular namesake Steam video game storefront and is the primary operating system for Steam Machines and the Steam Deck. SteamOS is open source with some closed source components. SteamOS was originally built to support streaming of video games from one personal computer to the one running SteamOS within the same network, although the operating system can support standalone systems and was intended to be used as part of Valve's Steam Machine platform. SteamOS versions 1.0, released in December 2013, and 2.0 were based on the Debian distribution of Linux with GNOME desktop. With SteamOS, Valve encouraged developers to incorporate Linux compatibility into their releases to better support Linux gaming options.
SteamOS:
In February 2022, Valve released the handheld gaming computer Steam Deck running SteamOS 3.0. SteamOS 3 is based on the Arch Linux distribution with KDE Plasma 5.
Features:
SteamOS is designed primarily for playing video games away from a PC (such as from the couch in one's living room) by providing a console-like experience using generic PC hardware that can connect directly to a television. It can run games natively that have been developed for Linux and purchased from the Steam store. Users are also able to stream games from their Windows, Mac or Linux computers to one running SteamOS, and it incorporates the same family sharing and restrictions as Steam on the desktop. Valve claims that it has "achieved significant performance increases in graphics processing" through SteamOS. The operating system is open source, allowing users to build on or adapt the source code, though the actual Steam client is closed.Since SteamOS is solely for playing games without a mouse or keyboard, it does not have many built-in functions beyond web browsing and playing games. Users can, however, access the KDE Plasma 5 desktop environment and perform tasks such as installing other software. The OS natively supports Nvidia, Intel, and AMD graphics processors.Valve stated that it has added support for movies, television, and music to SteamOS. However, video content is only available from Steam's store, which has a small number of films. Music playback only supports local music collections. In October 2015, an update allowed Netflix and other DRM protected content to function in the native built-in browser.The current system hardware requirements for default SteamOS 2.0 installations include: Intel or AMD 64-bit capable processor At least 4 GB of RAM At least 200 GB on one's hard disk NVIDIA (Fermi graphics cards (GeForce 400 series and GeForce 500 series) or newer), Intel, or AMD graphics card (RADEON 8500 or newer) USB port for installation UEFI boot supportA custom installer method is also available, which can require additional configuration steps. This method allows for smaller hard-disk sizes. There is also an ISO image installer that supports legacy BIOS motherboard. The installers can be sourced through Valve's repository.
Development:
During a panel at LinuxCon on September 16, 2013, Valve co-founder and executive director Gabe Newell stated that he believed "Linux and open source are the future of gaming", going on to say that the company was aiding game developers who want to make games compatible with Linux, and that they would be making an announcement the following week related to introducing Linux into the living room. On September 20, 2013, Valve posted a statement on its website titled The Steam Universe is Expanding in 2014 which teased three new announcements related to "even more ways to connect the dots for customers who want Steam in the living-room". The first announcement was made on September 23 as SteamOS, with Valve saying they had "come to the conclusion that the environment best suited to delivering value to customers is an operating system built around Steam itself". A large focus of the reveal was the openness of the operating system, with it being announced that users would be able to alter or replace any part of the software, and that it would be free.In October 2013, Valve announced Steam Dev Days; a two-day developer conference where video game developers could test and provide feedback on SteamOS and Steam Machines. In October 2013, Nvidia also announced their collaboration with Valve to support SteamOS with the help of a development suite called Nvidia GameWorks which incorporates PhysX, OptiX, VisualFX and other Nvidia-proprietary APIs and implementations thereof.In November 2013, Valve confirmed that they would not be making any exclusive games for SteamOS, and discouraged other developers from doing so, as it goes against their philosophy of selling games wherever customers are. In December, Valve announced that a beta version of SteamOS would be released on December 13, 2013. When this beta version released, Valve encouraged customers unfamiliar with Linux to wait until 2014.In mid-October 2015, preorders of the Steam Controller, Steam Link, and Alienware branded Steam Machines became available. The official release date for Steam Machines was on November 10, 2015.On July 15, 2021, Valve announced the Steam Deck, a brand new handheld PC gaming device. The Steam Deck runs a customized version of Steam OS 3.0 that is based upon Arch Linux, with the desktop mode being powered by KDE Plasma 5. The decision to move from Debian to Arch Linux was based on the different update schedule for these distributions. Debian, geared for server configurations, has its core software update in one large package with intermediate patches for known bug and security fixes, while Arch uses a rolling update approach for all parts. Valve found that the rolling update approach would be better suited for the Steam Deck, allowing them to address issues and fixes much faster than Debian would allow. Valve affirmed that SteamOS 3.0 will continue to be freely available, with the intention of allowing other hardware developers to take advantage of it and build similar handheld computing devices like the Deck.
Releases and performance:
SteamOS 1.0 beta In December 2013, Phoronix compared three Nvidia graphics cards on SteamOS 1.0 beta and Windows 8.1 Pro. Overall, Nvidia's proprietary Linux graphics driver delivered performance comparable to that of the Windows drivers due to the platforms’ largely shared codebase.
Releases and performance:
In January 2014, GameSpot compared the performance of three games (Dota 2, Left 4 Dead 2, and Metro: Last Light) running on Windows 7 x64 and SteamOS 1.0 beta. With an AMD graphics card, they found that all ran at considerably fewer frames per second on SteamOS, and Left 4 Dead 2 stuttered, which they attributed to a device driver problem. With an Nvidia graphics card, they found that Metro: Last Light ran at a slightly higher frame rate and Dota 2 broke even. With both video card brands, Left 4 Dead 2 and Dota 2 had longer load times on SteamOS.
Releases and performance:
SteamOS 2 When Steam Machines was officially released in November 2015, Ars Technica compared the rendering performance of cross-platform games on SteamOS 2 and Windows 10 running on the same machine, using average frame-per-second measurements, and found that games rendered between 21% and 58% slower on SteamOS 2. Ars Technica suggested this might be due to the inexperience of developers optimizing on OpenGL in contrast to DirectX, and believed that the performance might improve with future titles. They noted that their benchmark test, using six games on a single computer, was far from comprehensive.
Releases and performance:
SteamOS 3 (on Steam Deck hardware) In March 2022, Linus Tech Tips compared SteamOS 3 performance using three gaming benchmarks (including Hitman 3, Doom Eternal, and Elden Ring) showing all three titles having a higher average frames per second on SteamOS 3 compared to Windows 10. Hitman 3 delivered a 19 fps average for Windows 10 and a 34 fps average for SteamOS 3. In Doom Eternal, SteamOS 3 hit a 60 fps average while Windows hit a 47 fps average. Elden Ring on SteamOS topping out at 37 fps average while running on Windows 10 at a 30 fps average.
Reception:
Following SteamOS’ initial announcement, many video game developers expressed enthusiasm. Minecraft creator Markus Persson described it as "amazing news," and Thomas Was Alone developer Mike Bithell called it "encouraging" for indie games. Other developers such as DICE, creators of the Battlefield series, and The Creative Assembly, developers of the Total War series, stated that they may add Linux support for their games following SteamOS’ release.On the operating system front, Gearbox Software head Randy Pitchford expressed a belief that the operating system needed a unique application to attract developers, saying "without that must-buy product driving us all towards this stuff, I expect that the industry at large will watch curiously, but remain largely unaffected." Richard Stallman, former president of the Free Software Foundation, expressed cautious support, but does not condone the use of non-free games or DRM.The SteamOS beta release received mixed reviews. In TechRadar's review Henry Winchester praised the easy to navigate interface and future potential but criticized the hard installation and lack of extra features compared to the Steam software. Eurogamer's Thomas Morgan did not experience installation problems, but commented negatively on the lack of options available for detecting monitor resolutions and audio output, in addition to the lack of games available natively on the operating system. However, he responded well to the user interface, calling it "a positive start".Since then, outlets such as Ars Technica have revisited the SteamOS since its initial debut, offering observations on the platform's growth, pros, and cons. Both Falcon Northwest and Origin PC, computer manufacturers that were planning on offering Steam Machine hardware, opted to not ship a SteamOS-enabled machine in 2015 due to limitations of SteamOS over Windows; Falcon Northwest said they would still consider shipping machines with SteamOS in the future if performance improves. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Boi Faltings**
Boi Faltings:
Boi Volkert Faltings (born April 10, 1960) is a Swiss professor of artificial intelligence at École Polytechnique Fédérale de Lausanne.
Education:
Faltings was born in Gelsenkirchen, Germany, and he received a diploma with distinction from ETH Zurich in 1983, where he studied electrical engineering with James Massey. He obtained a Ph.D. degree from the University of Illinois at Urbana–Champaign in 1987 under the supervision of Ken Forbus. His thesis was entitled "Qualitative kinematics in mechanisms" and showed for the first time how to derive kinematic interactions from object shapes.
Work:
Faltings is noted for work in artificial intelligence, especially in qualitative reasoning about mechanisms, case-based reasoning in design, constraint satisfaction in design and logistics, and intelligent user interfaces. His recent work has centered on multi-agent systems, in particular the DPOP family of algorithms for distributed constraint optimization, the blocking island abstraction technique for network routing, and game-theoretic techniques for eliciting truthful information, in particular the peer truth serum.In 1997, Faltings co-founded the company Iconomic Systems, known for development of an agent-based paradigm for travel e-commerce. He subsequently co-founded 5 other companies. Among them, in 2004 he co-founded NexThink, providing network security and data analytics. In 2007, he co-founded Prediggo, a company that provides recommender systems.Faltings was nominated professor at the Ecole Polytechnique Fédérale de Lausanne in 1987 and promoted to full professor in 1993. He founded the Artificial Intelligence Laboratory and served as head for the Department of Computer Science. He has spent 6 months each as visiting professor at Stanford University and the Hong Kong University of Science and Technology. He has served as associate editor for numerous journals, including the Journal of Artificial Intelligence Research, the Artificial Intelligence, the ACM Transactions on Intelligent Systems and Technology, the ACM Transactions on Economics and Computation, and the ACM Transactions on Social Computing. He was president of the Swiss Group for Artificial Intelligence and Cognitive Science from 1995 to 2014, and member of the executive council of the Association for Advancement of Artificial Intelligence from 2014 to 2017.
Honors:
In 1983, Faltings received the silver medal of the ETH Zurich for his diploma thesis. In 1984, he received an IBM graduate fellowship. In 2000, he received a distinguished service award from IFIP. In 2002, he was elected a Fellow of the European Coordinating Committee for Artificial Intelligence, and in 2012, he was elected a Fellow of the Association for the Advancement of Artificial Intelligence.
Selected publications:
He is the main author (with Goran Radanovic) of Game Theory for Data Science. Morgan Claypool, 2017, which summarizes recent work on game-theoretic mechanisms for eliciting truthful information.
Two representative publications on this topic are: "An incentive compatible reputation mechanism" (with Radu Jurca). in E-Commerce, 2003. CEC 2003. IEEE International Conference on Electronic Commerce 2003 Jun 24 (pp. 285–292). IEEE.
Selected publications:
"Incentives for effort in crowdsourcing using the peer truth serum" (with Radu Jurca and Goran Radanovic). ACM Transactions on Intelligent Systems and Technology (TIST). 14;7(4):48, 2016His most cited work introduces the DPOP algorithm for distributed constraint optimization: "A scalable method for multiagent constraint optimization"(with Adrian Petcu), Proceedings of the 19th International Joint Conference on Artificial Intelligence (IJCAI), pp. 266–27, 2005. [1] According to Google Scholar, this paper has been cited 642 times as of December 2018Important subsequent works on distributed constraint optimization include: The most general version of the DPOP algorithm: "MB-DPOP: A New Memory-Bounded Algorithm for Distributed Optimization " (with Adrian Petcu), Proceedings of the 20th International Joint Conference on Artificial Intelligence (IJCAI), pp. 1452–1457, 2007 The first fully private version of the DPOP algorithm: "Privacy guarantees through distributed constraint satisfaction" (with Adrian Petcu and Thomas Léauté) WI-IAT 2008. IEEE/WIC/ACM International Conference on Intelligent Agent Technology (Vol. 2, pp. 350–358). IEEE, 2008Other important peer-reviewed publications are: Using qualitative reasoning for design: "FAMING: Supporting innovative mechanism shape design" (with Kun Sun). Computer-Aided Design, 28(3), pp. 207–216, 1996 The main patent underlying the blocking islands method: "Method of management in a circuit-switched communication network and device which can be used as a node in a circuit-switched communication network," US patent No. 6,842,780 The main patent underlying the company NexThink: "Method of detecting anomalous behaviour in a computer network." US Patent 8,631,464, 2014 "A budget-balanced, incentive-compatible scheme for social choice." Agent-Mediated Electronic Commerce VI. Theories for and Engineering of Distributed Mechanisms and Systems, pp. 30–43. Springer LNCS 3435, 2004.
Selected publications:
The ontology filtering technology underlying the company Prediggo: "OSS: A Semantic Similarity Function based on Hierarchical Ontologies" (with Vincent Schickel). Proceedings of the 20th International Joint Conference on Artificial Intelligence (IJCAI), pp. 551–556, 2007 "Understanding and improving relational matrix factorization in recommender systems" (with Li Pu). In Proceedings of the 7th ACM Conference on Recommender Systems (pp. 41–48). ACM, 2013 | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**IEEE 802.11s**
IEEE 802.11s:
IEEE 802.11s is a wireless local area network (WLAN) standard and an IEEE 802.11 amendment for mesh networking, defining how wireless devices can interconnect to create a wireless LAN mesh network, which may be used for relatively fixed (not mobile) topologies and wireless ad hoc networks. The IEEE 802.11s task group drew upon volunteers from university and industry to provide specifications and possible design solutions for wireless mesh networking. As a standard, the document was iterated and revised many times prior to finalization.
IEEE 802.11s:
802.11 are a set of IEEE standards that govern wireless networking transmission protocols. They are commonly used today to provide wireless connectivity in the home, office and some commercial establishments.
The IEEE 802.11s standard was issued in 2011 and was superseded in 2012 when it became part of the IEEE 802.11 standard that was issued in 2012.
Description:
802.11s extends the IEEE 802.11 MAC standard by defining an architecture and protocol that supports both broadcast/multicast and unicast delivery using "radio-aware metrics over self-configuring multi-hop topologies."
Closely related standards:
802.11s inherently depends on one of 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, or 802.11ax to carry the actual traffic. One or more routing protocols suitable to the actual network physical topology are required. 802.11s requires the Hybrid Wireless Mesh Protocol, or HWMP to be supported as a default. However, other mesh, ad hoc (Associativity-Based Routing, Zone Routing Protocol, and location based routing) or dynamically link-state routed (OLSR, B.A.T.M.A.N., OSPF) may be supported or even static routing (WDS). See the more detailed description below comparing these routing protocols.
Closely related standards:
A mesh often consists of many small nodes. When mobile users or heavy loads are concerned, there will often be a handoff from one base station to another, and not only from 802.11 but from other (GSM, Bluetooth, PCS and other cordless phone) networks. Accordingly, IEEE 802.21, which specifies this handoff between nodes both obeying 802.11s and otherwise, may be required. This is especially likely if a longer-range lower-bandwidth service is deployed to minimize mesh dead zones, e.g. GSM routing based on OpenBTS.
Closely related standards:
Mesh networking often involves network access by previously unknown parties, especially when a transient visitor population is being served. Thus the accompanying IEEE 802.11u standard will be required by most mesh networks to authenticate these users without pre-registration or any prior offline communication. Pre-standard captive portal approaches are also common. See the more detailed description below of mesh security.
Timeline:
802.11s started as a Study Group of IEEE 802.11 in September 2003. It became a Task Group in July 2004. A call for proposals was issued in May 2005, which resulted in the submission of 15 proposals submitted to a vote in July 2005. After a series of eliminations and mergers, the proposals dwindled to two (the "SEE-Mesh" and "Wi-Mesh" proposals), which became a joint proposal in January 2006. This merged proposal was accepted as draft D0.01 after a unanimous confirmation vote in March 2006.
Timeline:
The draft evolved through informal comment resolution until it was submitted for a Letter Ballot in November 2006 as Draft D1.00. Draft D2.00 was submitted in March 2008 which failed with only 61% approval. A year was spent clarifying and pruning until Draft D3.00 was created which reached WG approval with 79% in March 2009.
In June 2011 the fifth recirculation Sponsor Ballot, on TGs Draft 12.0, was closed. The Draft met with 97.2% approval rate.The 2012 release of the 802.11 specification (802.11-2012) directly incorporates Mesh Routing functionality.
802.11 mesh architecture:
An 802.11s wireless mesh network device is labelled as Mesh Station (mesh STA), or simply an ad hoc node. Mesh STAs form mesh links with one another, over which mesh paths can be established using an ad hoc mobile routing protocol. A key aspect of this architecture is the presence of multi-hop wireless links and routing of packets through other nodes towards the destination node.
802.11 mesh architecture:
Routing protocols This should be expanded into a treatment of all the compatible routing protocols.
802.11 mesh architecture:
802.11s defines a default mandatory routing protocol (Hybrid Wireless Mesh Protocol, or HWMP), yet allows vendors to operate using alternate routing protocols. HWMP is inspired by a combination of AODV (RFC 3561), which uses on-demand ad hoc routing approach and tree-based routing. Examples of on-demand ad hoc routing are Dynamic Source Routing and Associativity-Based Routing. AODV route discovery and localized route repair approaches are identical to Associativity-based Routing. Prior work has discussed and compared these various routing protocols in detail.Mesh STAs are individual devices using mesh services to communicate with other devices in the network. They can also collocate with 802.11 Access Points (APs) and provide access to the mesh network to 802.11 stations (STAs), which have broad market availability. Also, mesh STAs can collocate with an 802.11 portal that implements the role of a gateway and provides access to one or more non-802.11 networks. In both cases, 802.11s provides a proxy mechanism to provide addressing support for non-mesh 802 devices, allowing for end-points to be cognizant of external addresses.
802.11 mesh architecture:
802.11s also includes mechanisms to provide deterministic network access, a framework for congestion control and power save.
Mesh security There are no defined roles in a mesh — no clients and servers, no initiators and responders. Security protocols used in a mesh must, therefore, be true peer-to-peer protocols where either side can initiate to the other or both sides can initiate simultaneously.
802.11 mesh architecture:
Peer authentication methods Between peers, 802.11s defines the secure password-based authentication and key establishment protocol Simultaneous Authentication of Equals (SAE). SAE is based on Diffie–Hellman key exchange using finite cyclic groups which can be a primary cyclic group or an elliptic curve. The problem with a Diffie–Hellman key exchange is that it does not have an authentication mechanism. So the resulting key is influenced by a pre-shared key and the MAC addresses of both peers to solve the authentication problem.
802.11 mesh architecture:
When peers discover each other (and security is enabled) they take part in an SAE exchange. If SAE completes successfully, each peer knows the other party possesses the mesh password and, as a by-product of the SAE exchange, the two peers establish a cryptographically strong key. This key is used with the "Authenticated Mesh Peering Exchange" (AMPE) to establish a secure peering and derive a session key to protect mesh traffic, including routing traffic.
Implementations:
The IEEE 802.11s amendment is supported by many products such as open80211s, OLPC. In open80211s smaller meshes of under 32 nodes are supported. Some of the projects were based on earlier (draft) versions.
A reference implementation of the 802.11s draft is available as part of the mac80211 layer in the Linux kernel, starting with version 2.6.26. The Linux community, with its many diverse distributions, provides a heterogenous testing ground for protocols like Hybrid Wireless Mesh Protocol. OpenWrt, a Linux distribution for routers, supports mesh networking.
In FreeBSD, the 802.11s draft is supported starting with FreeBSD 8.0.
The Google Wifi router uses the 802.11s mesh networking protocol.
The MeshPoint.One router uses 802.11s mesh networking protocol. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Tianeptine**
Tianeptine:
Tianeptine, sold under the brand names Stablon, Tatinol, and Coaxil among others, is an atypical tricyclic antidepressant which is used mainly in the treatment of major depressive disorder, although it may also be used to treat anxiety, asthma, and irritable bowel syndrome.Tianeptine has antidepressant and anxiolytic effects with a relative lack of sedative, anticholinergic, and cardiovascular side effects. It has been found to act as an atypical agonist of the μ-opioid receptor with clinically negligible effects on the δ- and κ-opioid receptors. This may explain part of its antidepressant and anxiolytic effects, however, it is thought that tianeptine also modulates glutamate receptors, and this may also explain Tianeptine's antidepressant/anxiolytic effects.
Tianeptine:
Tianeptine was discovered and patented by the French Society of Medical Research in the 1960s. Currently, tianeptine is approved in France and manufactured and marketed by Laboratories Servier SA; it is also marketed in a number of other European countries under the trade name Coaxil as well as in Asia (including Singapore) and Latin America as Stablon and Tatinol but it is not available in Australia, Canada, New Zealand, or the United Kingdom.
Medical uses:
Depression and anxiety Tianeptine shows efficacy against serious depressive episodes (major depression), comparable to amitriptyline, imipramine and fluoxetine, but with significantly fewer side effects. It was shown to be more effective than maprotiline in a group of people with co-existing depression and anxiety. Tianeptine also displays significant anxiolytic properties and is useful in treating a spectrum of anxiety disorders including panic disorder, as evidenced by a study in which those administered 35% CO2 gas (carbogen) on paroxetine or tianeptine therapy showed equivalent panic-blocking effects. Like many antidepressants (including bupropion, the selective serotonin reuptake inhibitors, the serotonin-norepinephrine reuptake inhibitors, moclobemide and numerous others) it may also have a beneficial effect on cognition in people with depression-induced cognitive dysfunction.
Medical uses:
A 2005 study in Egypt showed tianeptine to be effective in men with depression and erectile dysfunction.Tianeptine has been found to be effective in depression, in people with Parkinson's disease, and with post-traumatic stress disorder for which it was as safe and effective as fluoxetine and moclobemide.
Medical uses:
Other uses A clinical trial comparing its efficacy and tolerability with amitriptyline in the treatment of irritable bowel syndrome showed that tianeptine was at least as effective as amitriptyline and produced fewer prominent adverse effects, such as dry mouth and constipation.Tianeptine has been reported to be very effective for asthma. In August 1998, Dr. Fuad Lechin and colleagues at the Central University of Venezuela Institute of Experimental Medicine in Caracas published the results of a 52-week randomized controlled trial of asthmatic children; the children in the groups who received tianeptine had a sharp decrease in clinical rating and increased lung function. Two years earlier, they had found a close, positive association between free serotonin in plasma and severity of asthma in symptomatic persons. As tianeptine was the only agent known to both reduce free serotonin in plasma and enhance uptake in platelets, they decided to use it to see if reducing free serotonin levels in plasma would help. By November 2004, there had been two double-blind placebo-controlled crossover trials and an under-25,000 person open-label study lasting over seven years, both showing effectiveness.Tianeptine also has anticonvulsant and analgesic effects, and a clinical trial in Spain that ended in January 2007 has shown that tianeptine is effective in treating pain due to fibromyalgia. Tianeptine has been shown to have efficacy with minimal side effects in the treatment of attention-deficit hyperactivity disorder.
Contraindications:
Known contraindications include the following: Hypersensitivity to tianeptine or any of the tablet's excipients.
Side effects:
Compared to other tricyclic antidepressants, it produces significantly fewer cardiovascular, anticholinergic (like dry mouth or constipation), sedative and appetite-stimulating effects. A recent review found that it was amongst the antidepressants most prone to causing hepatotoxicity (liver damage), although the evidence to support this concern was of limited quality. Unlike other tricyclic antidepressants, tianeptine does not affect heart function. μ-Opioid receptor agonists can sometimes induce euphoria, as does tianeptine, occasionally, at high doses, well above the normal therapeutic range. Tianeptine can also cause severe withdrawal symptoms after prolonged use at high doses which should prompt extreme caution.
Side effects:
By frequency Sources: Common (>1% frequency) Uncommon (0.1-1% frequency) Rare (<0.1% frequency)
Pharmacology:
Pharmacodynamics Atypical μ-opioid receptor agonist In 2014, tianeptine was found to be a μ-opioid receptor (MOR) full agonist using human proteins. It was also found to act as a full agonist of the δ-opioid receptor (DOR), although with approximately 200-fold lower potency. The same researchers subsequently found that the MOR is required for the acute and chronic antidepressant-like behavioral effects of tianeptine in mice and that its primary metabolite had similar activity as a MOR agonist but with a much longer elimination half-life. Moreover, in mice, although tianeptine produced other opioid-like behavioral effects such as analgesia and reward, it did not result in tolerance or withdrawal. The authors suggested that tianeptine may be acting as a biased agonist of the MOR and that this may be responsible for its atypical profile as a MOR agonist. However, there are reports that suggest that withdrawal effects resembling those of other typical opioid drugs (including but not limited to depression, insomnia, and cold/flu-like symptoms) do manifest following prolonged use at dosages far beyond the medical range. In addition to its therapeutic effects, activation of the MOR is likely to also be responsible for the abuse potential of tianeptine at high doses that are well above the normal therapeutic range and efficacy threshold.
Pharmacology:
In rats, when co-administered with morphine, tianeptine prevents morphine-induced respiratory depression without impairing analgesia. In humans, however, tianeptine was found to increase respiratory depression when administered in conjunction with the potent opioid remifentanil.
Pharmacology:
Glutamatergic, neurotrophic, and neuroplastic modulation Research suggests that tianeptine produces its antidepressant effects through indirect alteration and inhibition of glutamate receptor activity (i.e., AMPA receptors and NMDA receptors) and release of BDNF, in turn affecting neural plasticity. Some researchers hypothesize that tianeptine has a protective effect against stress induced neuronal remodeling. There is also action on the NMDA and AMPA receptors. In animal models, tianeptine inhibits the pathological stress-induced changes in glutamatergic neurotransmission in the amygdala and hippocampus. It may also facilitate signal transduction at the CA3 commissural associational synapse by altering the phosphorylation state of glutamate receptors. With the discovery of the rapid and novel antidepressant effects of drugs such as ketamine, many believe the efficacy of antidepressants is related to promotion of synaptic plasticity. This may be achieved by regulating the excitatory amino acid systems that are responsible for changes in the strength of synaptic connections as well as enhancing BDNF expression, although these findings are based largely on preclinical studies.
Pharmacology:
Serotonin reuptake enhancer Tianeptine is no longer labelled a Selective Serotonin Reuptake Enhancer (SSRE) antidepressant.
Pharmacology:
Tianeptine had been found to bind to the same allosteric site on the serotonin transporter (SERT) as conventional TCAs. However, whereas conventional TCAs inhibit serotonin reuptake by the SERT, tianeptine appeared to enhance it. This seems to be because of the unique C3 amino heptanoic acid side chain of tianeptine, which, in contrast to other TCAs, is thought to lock the SERT in a conformation that increases affinity for and reuptake (Vmax) of serotonin. As such, tianeptine was thought to act a positive allosteric modulator of the SERT, or as a "serotonin reuptake enhancer".Although tianeptine was originally found to have no effect in vitro on monoamine reuptake, release, or receptor binding, upon acute and repeated administration, tianeptine decreased the extracellular levels of serotonin in rat brain without a decrease in serotonin release, leading to a theory of tianeptine enhancing serotonin reuptake. The (−)-enantiomer is more active in this sense than the (+)-enantiomer. However, more recent studies found that long-term administration of tianeptine does not elicit any marked alterations (neither increases nor decreases) in extracellular levels of serotonin in rats. However, coadministration of tianeptine and the selective serotonin reuptake inhibitor fluoxetine inhibited the effect of tianeptine on long-term potentiation in hippocampal CA1 area. This is considered an argument for the opposite effects of tianeptine and fluoxetine on serotonin uptake, although it has been shown that fluoxetine can be partially substituted for tianeptine in animal studies. In any case, the collective research suggests that direct modulation of the serotonin system is unlikely to be the mechanism of action underlying the antidepressant effects of tianeptine.
Pharmacology:
Other actions Tianeptine modestly enhances the mesolimbic release of dopamine and potentiates CNS D2 and D3 receptors. Tianeptine has no affinity for the dopamine transporter or the dopamine receptors. CREB-TF (CREB, cAMP response element-binding protein) is a cellular transcription factor. It binds to certain DNA sequences called cAMP response elements (CRE), thereby increasing or decreasing the transcription of the genes. CREB has a well-documented role in neuronal plasticity and long-term memory formation in the brain. Cocaine- and amphetamine-regulated transcript, also known as CART, is a neuropeptide protein that in humans is encoded by the CARTPT gene. CART appears to have roles in reward, feeding, stress, and it has the functional properties of an endogenous psychostimulant. Taking into account that CART production is upregulated by CREB, it could be hypothesized that due to tianeptine's central role in BDNF and neuronal plasticity, this CREB may be the transcription cascade through which this drug enhances mesolimbic release of dopamine.
Pharmacology:
Research indicates possible anticonvulsant (anti-seizure) and analgesic (painkilling) activity of tianeptine via downstream modulation of adenosine A1 receptors (as the effects could be experimentally blocked by antagonists of this receptor). Tianpetine is also weak histone deacetylase inhibitor and analogs with increased potency and selectivity are developed.
Pharmacology:
Pharmacokinetics The bioavailability of tianeptine is approximately 99%. Its plasma protein binding is about 95%. The metabolism of tianeptine is hepatic, via β-oxidation. CYP enzymes are not involved, which limits the potential for drug-drug interactions. Maximal concentration is reached in about an hour and the elimination half-life is 2.5 to 3 hours. The elimination half-life has been found to be increased to 4 to 9 hours in the elderly. Tianeptine is usually packaged as a sodium salt but can also be found as tianeptine sulfate, a slower-releasing formulation patented by Janssen in 2012. In 2022 Tonix Pharmaceuticals received permission from the US FDA to conduct phase II clinical trials on tianeptine hemioxalate extended-release tablets designed for once-daily use.Tianeptine has two active metabolites, MC5 (a pentanoic acid derivative of the parent compound) and MC3 (a propionic acid derivative). MC5 has a longer elimination half-life of approximately 7.6 hours, and takes about a week to reach steady-state concentration under daily-dosing. MC5 is a mu-opioid agonist but not delta-opioid agonist, with EC50 at the mu-opioid receptor of 0.545 μM (vs 0.194 μM for tianeptine). MC3 is a very weak mu-opioid agonist, with an EC50 of 16 μM. Tianeptine is excreted 65% in the urine and 15% in feces.
Chemistry:
In terms of chemical structure, it is similar to tricyclic antidepressants (TCAs), but it has significantly different pharmacology and important structural differences, so it is not usually grouped with them.
Chemistry:
Analogues Although several related compounds are disclosed in the original patent, no activity data are provided and it was unclear whether these share tianeptine's unique pharmacological effects. More recent structure-activity relationship studies have since been conducted, providing some further insight on μ-opioid, δ-opioid, and pharmacokinetic activity. Derivatives where the aromatic chlorine substituent is replaced by bromine, iodine or methylthio, and/or the heptanoic acid tail is varied in length or replaced with other groups such as 3-methoxypropyl, show similar or increased opioid receptor activity relative to tianeptine itself. Amineptine, the most closely related drug to have been widely studied, is a dopamine reuptake inhibitor with no significant effect on serotonin levels, nor opioid agonist activity. Tianeptinaline, analog of tianeptine, is a notable class I HDAC inhbitor.
Society and culture:
Approval and brand names Brand names include: Coaxil (BG, CZ, EE, HU, LT, LV, PL, RO, RU, UA) Salymbra (EE) Stablon (AR, AT, BR, FR, IN, ID, MY, MX, PK, PT, SG, SK, TH, TT, TR, VE) Tatinol (CN) Tiana Red or Tiana (US) Tianeurax (DE) Tynept (IN) Zaza Red (US) Zinosal (ES) Development Under the code names JNJ-39823277 and TPI-1062, tianeptine was previously under development for the treatment of major depressive disorder in the United States and Belgium. Phase I clinical trials were completed in Belgium and the United States in May and June 2009, respectively. For unclear reasons development of tianeptine was discontinued in both countries in January 2012.The U.S. National Poison Data System data on tianeptine showed a nationwide increase in tianeptine exposure calls and calls related to abuse and misuse during 2014–2017.
Society and culture:
Recreational use As a μ-opioid agonist, tianeptine in large doses has high abuse potential. In 2001, Singapore's Ministry of Health restricted tianeptine prescribing to psychiatrists due to its recreational potential.Between 1989 and 2004, in France 141 cases of recreational use were identified, correlating to an incidence of 1 to 3 cases per 1000 persons treated with tianeptine and 45 between 2006 and 2011. According to Servier, stopping of treatment with tianeptine is difficult, due to the possibility of withdrawal symptoms in a person. The severity of the withdrawal is dependent on the daily dose, with high doses being extremely difficult to quit. Official DEA statement states that the withdrawal symptoms in humans typically result in: agitation, nausea, vomiting, tachycardia, hypertension, diarrhea, tremor, and diaphoresis, similar to other opioid drugs.
Society and culture:
In 2007, according to French Health Products Safety Agency, tianeptine's manufacturer Servier agreed to modify the drug's label, following problems with dependency.Tianeptine has been intravenously injected by drug users in Russia. This method of administration reportedly causes an opioid-like effect and is sometimes used in an attempt to lessen opioid withdrawal symptoms. Tianeptine tablets contain silica and do not dissolve completely. Often the solution is not filtered well thus particles in the injected fluid block capillaries, leading to thrombosis and then severe necrosis. Thus, in Russia tianeptine (sold under the brand name "Coaxil") is a schedule III controlled substance in the same list as the majority of benzodiazepines and barbiturates.The Centers for Disease Control and Prevention (CDC) has expressed concern that tianeptine may be an "emerging public health risk", citing an increase in exposure-related calls to poison control centers in the United States.A literature review conducted in 2018 found 25 articles involving 65 patients with tianeptine abuse or dependence. Limited data showed that a majority of patients were male and that age ranged from 19 to 67. Routes of intake included oral, intravenous, and insufflation entry. In the 15 cases of overdose, 8 combined ingestion with at least one other substance, of which 3 resulted in death. Six additional deaths are reported involving tianeptine (making it 9 in total). In this report, the amount of tianeptine used ranged from 50 mg/day to 10g/day orally.
Legality:
In 2003, Bahrain classified tianeptine a controlled substance due to increasing reports of misuse and recreational use.In Russia, tianeptine (sold under the brand name "Coaxil") is a schedule III controlled substance in the same list as the majority of benzodiazepines and barbiturates.On March 13, 2020, with a decree approved by the Minister of Health, Italy became the first European country to ban tianeptine considering it a Class I controlled substance.In the United States, tianeptine is not considered by the Drug Enforcement Administration as controlled substance or analogue thereof. However, its use in dietary supplements and food is unlawful.On 6 April 2018 Michigan became the first U.S. state to ban tianeptine sodium, classifying it as a schedule II controlled substance. The scheduling of tianeptine sodium is effective 4 July 2018.On March 15, 2021, Alabama banned tianeptine, classifying it as a schedule II controlled substance .On July 1, 2022, Tennessee banned tianeptine and adds "any salt, sulfate, free acid, or other preparation of tianeptine, and any salt, sulfate, free acid, compound, derivative, precursor, or preparation thereof that is substantially chemically equivalent or identical with tianeptine", classifying it as a schedule II controlled substance.On December 22, 2022, Ohio banned tianeptine, classifying it as a schedule I controlled substance with Ohio Governor Mike DeWine referencing its availability there as “gas-station heroin.” | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Icositetragon**
Icositetragon:
In geometry, an icositetragon (or icosikaitetragon) or 24-gon is a twenty-four-sided polygon. The sum of any icositetragon's interior angles is 3960 degrees.
Regular icositetragon:
The regular icositetragon is represented by Schläfli symbol {24} and can also be constructed as a truncated dodecagon, t{12}, or a twice-truncated hexagon, tt{6}, or thrice-truncated triangle, ttt{3}.
One interior angle in a regular icositetragon is 165°, meaning that one exterior angle would be 15°.
The area of a regular icositetragon is: (with t = edge length) cot 24 =6t2(2+2+3+6).
The icositetragon appeared in Archimedes' polygon approximation of pi, along with the hexagon (6-gon), dodecagon (12-gon), tetracontaoctagon (48-gon), and enneacontahexagon (96-gon).
Construction As 24 = 23 × 3, a regular icositetragon is constructible using an angle trisector. As a truncated dodecagon, it can be constructed by an edge-bisection of a regular dodecagon.
Symmetry:
The regular icositetragon has Dih24 symmetry, order 48. There are 7 subgroup dihedral symmetries: (Dih12, Dih6, Dih3), and (Dih8, Dih4, Dih2 Dih1), and 8 cyclic group symmetries: (Z24, Z12, Z6, Z3), and (Z8, Z4, Z2, Z1).
Symmetry:
These 16 symmetries can be seen in 22 distinct symmetries on the icositetragon. John Conway labels these by a letter and group order. The full symmetry of the regular form is r48 and no symmetry is labeled a1. The dihedral symmetries are divided depending on whether they pass through vertices (d for diagonal) or edges (p for perpendiculars), and i when reflection lines path through both edges and vertices. Cyclic symmetries in the middle column are labeled as g for their central gyration orders.
Symmetry:
Each subgroup symmetry allows one or more degrees of freedom for irregular forms. Only the g24 subgroup has no degrees of freedom but can seen as directed edges.
Dissection:
Coxeter states that every zonogon (a 2m-gon whose opposite sides are parallel and of equal length) can be dissected into m(m-1)/2 parallelograms.
In particular this is true for regular polygons with evenly many sides, in which case the parallelograms are all rhombi. For the regular icositetragon, m=12, and it can be divided into 66: 6 squares and 5 sets of 12 rhombs. This decomposition is based on a Petrie polygon projection of a 12-cube.
Related polygons:
A regular triangle, octagon, and icositetragon can completely fill a plane vertex.
An icositetragram is a 24-sided star polygon. There are 3 regular forms given by Schläfli symbols: {24/5}, {24/7}, and {24/11}. There are also 7 regular star figures using the same vertex arrangement: 2{12}, 3{8}, 4{6}, 6{4}, 8{3}, 3{8/3}, and 2{12/5}.
There are also isogonal icositetragrams constructed as deeper truncations of the regular dodecagon {12} and dodecagram {12/5}. These also generate two quasitruncations: t{12/11}={24/11}, and t{12/7}={24/7}.
Skew icositetragon:
A skew icositetragon is a skew polygon with 24 vertices and edges but not existing on the same plane. The interior of such an icositetragon is not generally defined. A skew zig-zag icositetragon has vertices alternating between two parallel planes.
A regular skew icositetragon is vertex-transitive with equal edge lengths. In 3-dimensions it will be a zig-zag skew icositetragon and can be seen in the vertices and side edges of a dodecagonal antiprism with the same D12d, [2+,24] symmetry, order 48. The dodecagrammic antiprism, s{2,24/5} and dodecagrammic crossed-antiprism, s{2,24/7} also have regular skew dodecagons.
Petrie polygons The regular icositetragon is the Petrie polygon for many higher-dimensional polytopes, seen as orthogonal projections in Coxeter planes, including: | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Integrated Service Provider**
Integrated Service Provider:
An Integrated Service Provider (ISP) is a for-hire firm that performs a variety of logistics service activities such as warehousing, transportation, and other functional activities that constitute a total service package. In addition, other categories of spend may fall under the ISP's scope such as maintenance, repair, and operations (MRO) services. Firms that provide such services typically have a good understanding of their customers needs and are responsible for executing services in accordance with contract documents. Normally the scope of work (SOW) and the ISP contract are finalized only after an extensive due diligence period.
As a service:
The ISP provider may be contracted to perform a function or consolidate any number of activities required to support the customer's needs. In any case, normally the primary goal of the ISP is to achieve an overall cost savings for the customer. ISP providers normally work closely with the customer's management team within a facility to provide strategic sourcing to cut costs. In addition, the ISP and the customer normally will use key performance indicators that provide constant feedback on the performance of the ISP program. ISP firms can manage single or multiple categories of spend, such as facility management services, as part of a total integrated scope of work.
As a service:
Management of an ISP contract is typically a joint effort with both sides designating an ISP Manager. These managers will normally have quarterly review meetings to review performance and feedback with the customer's facility management team. Managers will also develop and review strategies related to spend management.
ISP firms may be required to hold certain permits or licenses in order to perform services. To obtain information on state requirements, a firm may check with the Contractor's License Reference website as well as the National Contractor's website.
ISP provider example:
An organization would start an ISP program in order to achieve a specific cost savings for its manufacturing facility. An ISP provider is selected at the owner's facility to conduct due diligence and analyze prior year spend data. After a thorough analysis by both parties, a contract is developed to meet mutually agreed objectives. Typically a go-live date is set to begin services. At this point the ISP provider has made all the appropriate preparations to provide agreed services. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**IBM 3584**
IBM 3584:
The IBM Tape Library 3584 also known as TS3500/TS4500 Tape Library. The number of tape drives it contains, is dependent on the frame's sub-model. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Propulsive fluid accumulator**
Propulsive fluid accumulator:
A Propulsive Fluid Accumulator is an artificial Earth satellite which collects and stores oxygen and other atmospheric gases for in-situ refuelling of high-thrust rockets. This eliminates the need to lift oxidizer to orbit and therefore brings significant cost benefits. A major portion of the total world payload sent into low earth orbit each year is either liquid oxygen or water.
Propulsive Fluid Accumulator (PROFAC):
In the period 1956 to 1963, S.T. Demetriades proposed methods of atmospheric gas accumulation by means of a satellite moving in low Earth orbit, at an altitude of around 120 km, or propellant accumulation by stations on the surface of a planet or by gathering and exploiting interstellar matter. In its simplest form, Demetriades' proposed satellite extracts air from the fringes of the atmosphere, compresses and cools it, and extracts liquid oxygen. The remaining nitrogen is, in part, used as propellant for a nuclear-powered magnetohydrodynamic electromagnetic plasma thruster, which maintains the orbit at about 120 km, or a solar powered thruster (and collection system) for altitudes above 150 km (as stated in the original 1959 JBIS article, p119) compensating for atmospheric drag. This system was called “PROFAC” (PROpulsive Fluid ACcumulator). Several systems were studied, e. g. PROFAC-S for Surface, PROFAC-C for Orbital, PROFAC-A for combination with aerospaceplane making one reusable stage to orbit possible, etc. Several inlets (e. g. conical as in AIEE 10 Aug 1960 San Diego meeting, or funnel) and cryopumps were studied for orbital air collection. The work slowed down in late 1961 although much progress was made in later years on such items as a solar-powered PROFAC.
Propulsive Fluid Accumulator (PROFAC):
There are, however, safety concerns with placing a nuclear reactor in low Earth orbit.
Propellant harvesting of atmospheric resources in orbit (PHARO):
Demetriades' proposal was further refined by Christopher Jones and others in 2010. In this proposal, multiple collection vehicles accumulate propellant gases at around 120 km altitude, later transferring them to a higher orbit. However, Jones' proposal does require a network of orbital power-beaming satellites, to avoid placing nuclear reactors in orbit.
Harvesting at about 200 kilometers altitude (LOX-LEO):
Klinkman and Wilkes proposed, at the AIAA Space 2007 and Space 2009 conferences, that gases could be harvested at the very edge of the earth's atmosphere by a high vacuum pump. An ion propulsion engine would consume a portion of the harvested gases and would restore the spacecraft's orbital momentum. Klinkman's proposal has a fairly low energy threshold for a small-scale harvesting operation, and air friction is far more forgiving at 200 km than at 100 km.Note that S. T. Demetriades pioneered in space propulsion, from the atomic oxygen ramjet (he proved it not feasible in the 1950s) to nuclear, ion, and plasma thrusters. He received the 2010 AIAA Award for Plasmadynamics and Lasers.
Propellant depots:
Boeing has suggested a non-extractive propellant depot, or "space gas station," which accumulates material launched from the planet at low cost, allowing future lunar missions without the need for large launch vehicles like the Saturn V. MIT has recently proposed a similar plan which would store emergency fuel reserves left over from lunar missions. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**XML for Analysis**
XML for Analysis:
XML for Analysis (XMLA) is an industry standard for data access in analytical systems, such as online analytical processing (OLAP) and data mining. XMLA is based on other industry standards such as XML, SOAP and HTTP. XMLA is maintained by XMLA Council with Microsoft, Hyperion and SAS Institute being the XMLA Council founder members.
History:
The XMLA specification was first proposed by Microsoft as a successor for OLE DB for OLAP in April 2000. By January 2001 it was joined by Hyperion endorsing XMLA. The 1.0 version of the standard was released in April 2001, and in September 2001 the XMLA Council was formed. In April 2002 SAS joined Microsoft and Hyperion as founding member of XMLA Council. With time, more than 25 companies joined with their support for the standard.
API:
XMLA consists of only two SOAP methods.: execute and discover. It was designed in such a way to preserve simplicity.
Execute Execute method has two parameters: Command - command to be executed. It can be MDX, DMX or SQL.
Properties - XML list of command properties such as Timeout, Catalog name, etc.The result of Execute command could be Multidimensional Dataset or Tabular Rowset.
Discover Discover method was designed to model all the discovery methods possible in OLEDB including various schema rowset, properties, keywords, etc. Discover method allows users to specify both what needs to be discovered and the possible restrictions or properties.
The result of Discover method is a rowset.
Query language:
XMLA specifies MDXML as the query language. In the XMLA 1.1 version, the only construct in MDXML is an MDX statement enclosed in the <Statement> tag.
Example:
Below is an example of XMLA Execute request with MDX query in command.
Session management:
XMLA has a notion of session state. It is maintained through predefined SOAP headers BeginSession - to begin a new session EndSession - to end existing session UseSession - to use existing session. SessionId attribute previously returned for BeginSession should be used. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Nucleoporin 37**
Nucleoporin 37:
Nucleoporin 37 (Nup37) is a protein that in humans is encoded by the NUP37 gene.
Function:
Transport of macromolecules between the cytoplasm and nucleus occurs through nuclear pore complexes (NPCs) embedded in the nuclear envelope. NPCs are composed of subcomplexes, and NUP37 is part of one such subcomplex, Nup107-160. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Step rent**
Step rent:
Step rent, also known as step-up rent or step-up lease, is a type of additional rent term found in commercial real estate where the rent increases or decreases at defined periods. It is generally used to simplify accounting by separating out the increases due to inflation into a separate row in the accounts.
Step rent:
For instance, a lease might specify the rent to be $1000 per month, and then add a second step rent term of $20 per year to account for inflation. Depending on the methodology, the term might be a simple dollar term, or it might be a percentage increase. The later is sometimes known as CPI rent, referring to the consumer price index, or CPI.
Step rent:
Modern electronic accounting systems can automatically apply such adjustments, and on such systems step rent may no longer be entered separately, but instead as part of the base rent terms. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Minima naturalia**
Minima naturalia:
Minima naturalia ("natural minima") were theorized by Aristotle as the smallest parts into which a homogeneous natural substance (e.g., flesh, bone, or wood) could be divided and still retain its essential character. In this context, "nature" means formal nature. Thus, "natural minimum" may be taken to mean "formal minimum": the minimum amount of matter necessary to instantiate a certain form.
Minima naturalia:
Speculation on minima naturalia in late Antiquity, in the Islamic world, and by Scholastic and Renaissance thinkers in Europe provided a conceptual bridge between the atomism of ancient Greece and the mechanistic philosophy of early modern thinkers like Descartes, which in turn provided a background for the rigorously mathematical and experimental atomic theory of modern science.
Aristotle's initial suggestion:
According to Aristotle, the Pre-Socratic Greek philosopher Anaxagoras had taught that every thing, and every portion of a thing, contains within itself an infinite number of like and unlike parts. For example, Anaxagoras maintained that there must be blackness as well as whiteness in snow; how, otherwise, could it be turned into dark water? Aristotle criticized Anaxagoras' theory on multiple grounds, among them the following: Animals and plants cannot be infinitely small according to Aristotle; thus the relatively homogeneous substances of which they are composed (e.g., bone and flesh in animals, or wood in plants) could not be infinitely small, either, but must have a smallest determinate size—i.e., a natural minimum.
Aristotle's initial suggestion:
On Anaxagoras' argument in which all things contain all others infinitely, water could be drawn from flesh, then flesh from that water, and water from that flesh, and so on. However, as above, because there is a smallest determinate size beyond which a further divided substance would no longer be flesh, any further cycle of such drawings out would be impossible.
Aristotle's initial suggestion:
Moreover, "[s]ince every body must diminish in size when something is taken from it, and flesh is quantitatively definite in respect both of greatness and smallness, it is clear that from the minimum quantity of flesh no body can be separated out; for the flesh left would be less than the minimum of flesh."Unlike the atomism of Leucippus, Democritus, and Epicurus, and also unlike the later atomic theory of John Dalton, the Aristotelian natural minimum was not conceptualized as physically indivisible--"atomic" in the contemporary sense. Instead, the concept was rooted in Aristotle's hylomorphic worldview, which held that every physical thing is a compound of matter (Greek hyle) and a substantial form (Greek morphe) that imparts its essential nature and structure. For instance, a rubber ball for a hylomorphist like Aristotle would be rubber (matter) structured by spherical shape (form).
Aristotle's initial suggestion:
Aristotle's intuition was that there is some smallest size beyond which matter could no longer be structured as flesh, or bone, or wood, or some other such organic substance that (for Aristotle, living before the microscope) could be considered homogeneous. For instance, if flesh were divided beyond its natural minimum, what would remain might be some elemental water, and smaller amounts of the other elements (e.g., earth) with which water was thought to mix to form flesh. But whatever was left, the water (or earth, etc.), would no longer have the formal "nature" of flesh in particular – the remaining matter would have the form of water (or earth, etc.) rather than the substantial form of flesh.
Aristotle's initial suggestion:
This is suggestive of modern chemistry, in which, e.g., a bar of gold can be continually divided until one has a single atom of gold, but further division of that atom of gold yields only subatomic particles (electrons, quarks, etc.) which are no longer the chemical element gold. Just as water alone is not flesh, electrons alone are not gold.
Scholastic elaboration:
Aristotle's brief comments on minima naturalia in the Physics and Meteorology prompted further speculations by later philosophers. The idea was taken up by John Philoponus and Simplicius of Cilicia in late Antiquity and by the Islamic Aristotelian Averroes (Ibn Rushd).
Scholastic elaboration:
Minima naturalia were discussed by Scholastic and Renaissance thinkers including Roger Bacon, Albertus Magnus, Thomas Aquinas, Giles of Rome, Siger of Brabant, Boethius of Dacia, Richard of Middleton, Duns Scotus, John of Jandun, William of Ockham, William Alnwick, Walter Bury, Adam de Wodeham, Jean Buridan, Gregory of Rimini, John Dumbleton, Nicole Oresme, John Marsilius Inguen, John Wycliffe, Albert of Saxony, Facinus de Ast, Peter Alboinis of Mantua, Paul of Venice, Gaetano of Thiene, Alessandro Achillini, Luis Coronel, Juan de Celaya, Domingo de Soto, Didacus de Astudillo, Ludovicus Buccaferrea, Francisco de Toledo, and Benedict Pereira. Of this list, the most influential Scholastic thinkers on minima naturalia were Duns Scotus and Gregory of Rimini.A chief theme in later commentary is reconciling minima naturalia with the general Aristotelian principle of infinite divisibility. Commentators like Philoponus and Aquinas reconciled these aspects of Aristotle's thought by distinguishing between mathematical and "natural" divisibility. For example, in his commentary on Aristotle's Physics, Aquinas writes of natural minima that, "although a body, considered mathematically, is divisible to infinity, the natural body is not divisible to infinity. For in a mathematical body nothing but quantity is considered. And in this there is nothing repugnant to division to infinity. But in a natural body the form also is considered, which form requires a determinate quantity and also other accidents. Whence it is not possible for quantity to be found in the species of flesh except as determined within some termini."
Influence on corpuscularianism:
In the early modern period, Aristotelian hylomorphism fell out of favor with the rise of the "mechanical philosophy" of thinkers like Descartes and John Locke, who were more sympathetic to the ancient Greek atomism of Democritus than to the natural minima of Aristotle. However, the concept of minima naturalia continued to shape philosophical thinking even among these mechanistic philosophers in the transitional centuries between the Aristotelianism of the medieval Scholastics and the worked-out atomic theory of modern scientists like Dalton.
Influence on corpuscularianism:
The mechanist Pierre Gassendi discussed minima naturalia in the course of expounding his opposition to Scholastic Aristotelianism, and his own attempted reconciliation between the atomism of Epicurus and the Catholic faith. Aristotle's mininima naturalia became "corpuscles" in the alchemical works of Geber and Daniel Sennert, who in turn influenced the corpuscularian alchemist Robert Boyle, one of the founders of modern chemistry. Boyle occasionally referred to his postulated corpuscles as minima naturalia. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Alpine planetary boundary layer**
Alpine planetary boundary layer:
The alpine planetary boundary layer is the planetary boundary layer (PBL) associated with mountainous regions. Due to its high spatial and temporal variability, its behavior is more complex than over a flat terrain. The fast changing local wind system directly linked to topography and the variable land cover that goes from snow to vegetation have a significant effect on the growth of the PBL and make it much harder to predict.
Alpine planetary boundary layer:
Understanding the processes inducing changes in the mountain PBL have critical applications for predicting air pollution transport, fire weather and local intense thunderstorm events. While some processes, such as mountain waves, have been well studied in the mountain PBL due to their importance for aviation, most of the behaviors of the alpine PBL are relatively unknown.
Wind systems:
The PBL in complex terrain is shaped by three local (non synoptic) wind systems occurring at different scales, which are closely related to the structure of the topography. The height of the PBL can be observed using radio soundings, which measure temperature and humidity gradients or LIDAR, which measures the backscatters of the aerosols.
Wind systems:
Mountain-Plain winds The Mountain-Plain winds system is the largest scale phenomenon going across the mountain range. During daytime, incoming solar radiation heats up the mountain top faster than the plain, creating a mean low pressure zone at the top. Winds then blow towards the mountain on all sides, flow up the slope and converge at the top. A return flow occurs aloft and comes back down into the plains. The exact opposite happens during nighttime, when the top cools down faster than the plain, which creates a mean high pressure zone leading to winds coming from the mountain top down to the plain. This represents the idealized situation since many complications can arise from cross currents, forced or pressure driven channeling or even cold fronts approaching the mountain barrier.
Wind systems:
Valley winds Valley winds are best developed on clear summer days and are driven by horizontal pressure gradients. During the day, the valley is warmer than the flat terrain (because it contains a smaller volume of air receiving the same amount of radiation), which creates a lower pressure zone over the valley, entraining the air from the plains up to the valley. The opposite process occurs at nighttime, where the valley cools faster and the air flows back down to the plains .
Wind systems:
Slope winds Slope-winds are produced by the temperature gradient between the valley and the air layer aloft. During daytime, the air above the valley on the slopes is warmer than at the bottom (due to a more direct exposure to incoming radiation), which leads to upslope flows converging at the ridge tops (and can lead to cloud formation depending on the humidity of the air parcel). At night, the air above the valley cools down faster than the surface leading to down-slope motion. This means that a temperature inversion occurs at night. The temperature increases from the bottom of the valley to the ridge top and then starts decreasing only when the air parcel is free from the influence of the topography. Again, this ideal circulation can often vary due to the complex topography. Insulation of the slopes is affected by shade, aspect and sky view factor, which is the portion of the visible sky not obscured by the relief. For instance, east facing slopes receive radiation earlier in the morning than west facing slopes, which affects how the PBL grows with time and space. A very good example of down-slope winds are the Santa Ana winds, which are dry and warm winds coming from the Great Basin and Mojave desert down to coastal South California.
PBL growth due to wind systems:
Diurnal variation Overall, plain to mountain, up-valley and up-slope winds occurring during the day locally increase the height of the PBL.
The PBL starts rising on the east facing slopes and near the ridges (warmed up by sun first and not hindered by pockets of cold air accumulated down the valley over night) and becomes more spatially homogeneous during the afternoon.
Temporally speaking, the convection ends around the early evening. Clouds then starts dissipating and the Mountain-Plain circulation starts reversing into a sinking motion. The transition builds up from the surface and becomes deeper and deeper with time.
The morning transition is slightly different and is the result of the combination of both the growth of the PBL and the sinking of the nocturnal temperature inversion.
At nighttime, there is a limited residual layer since advection by the mountain synoptic wind system dominates.
Mountain venting The daytime increase of the PBL from up-slope winds is called mountain venting. This phenomenon can sometimes cause a vertical exchange of the PBL air into the free troposphere.
Similarly to the daytime situation, during summer the top of the mountain is warmer than its surroundings creating a low pressure zone. Winds then blow up from the plains to the mountain top, which is an efficient lifting mechanism to carry PBL pollutants into the free atmosphere.
Effect of landcover:
Besides wind systems, the variation in land cover also plays a significant role in the PBL growth.
Bare or rocky soils are not the only land cover types found in high elevation, a more complex combination of snow and/or ice and/or vegetation is often observed. On such surfaces, the radiation energy budget is highly temporally and spatially variable and so is the growth of the PBL.
Effect of landcover:
Snow Due to wind, fresh snow does not stay at the surface but is blown into the first few meters of the surface layer. This blowing snow usually sublimates due to the insulation and has a significant meteorological effect . The sublimation of blowing snow leads to a modification of the energy budget and an overall temperature decrease of 0.5 °C combined to an increase of water vapor has been observed. This forms a stable cold and moist layer of air above the snow surface, even if the surrounding air temperature is above freezing point.
Effect of landcover:
This cold layer induces downslope winds, which damper the growth of the PBL.
This surface winds are also drifting the snowpack, leading to an increase of surface roughness and therefore an increase of wind shear (Forced convection).
Effect of landcover:
Vegetation Low vegetation cover such as grass or shrubs are usually covered by snow during winter time or at very high elevations and the modification in surface roughness is therefore of a limited magnitude. However, dense and high forests have a significant effect on surface roughness and also on the energy budget. The turbulence created by the vegetation canopy increases the forced convection in the surface layer. The top of the canopy has a tendency to warm up faster than the air at the bottom of the valley creating upslope wind conditions just from the presence of vegetation.
Effect of landcover:
To summarize, the presence of snow creates down-slope winds hindering the growth of the PBL while the presence of forest creates up-slope winds facilitating the growth of the PBL. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**GEOS circle**
GEOS circle:
In geometry, the GEOS circle is derived from the intersection of four lines that are associated with a generalized triangle: the Euler line, the Soddy line, the orthic axis and the Gergonne line. Note that the Euler line is orthogonal to the orthic axis and that the Soddy line is orthogonal to the Gergonne line.
These four lines provide six points of intersection of which two points occur at line intersections that are orthogonal. Consequently, the other four points form an orthocentric system.
The GEOS circle is that circle centered at a point equidistant from X650 (the intersection of the orthic axis with the Gergonne line) and X20 (the intersection of the Euler line with the Soddy line and is known as the de Longchamps point) and passes through these points as well as the two points of orthogonal intersection.
The orthogonal intersection points are X468 (the intersection of the orthic axis with the Euler line) and X1323 (the Fletcher point, the intersection of the Gergonne line with the Soddy line).
The orthocentric system comprises X650, X20, X1375 (the intersection of the Euler line with the Gergonne line and is known as the Evans point) and X3012 (the intersection of the Soddy line and the orthic axis).
The X(i) point notation is the Clark Kimberling ETC classification of triangle centers. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Essential oil**
Essential oil:
An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted, such as oil of clove. An essential oil is essential in the sense that it contains the essence of the plant's fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does not mean indispensable or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism.Essential oils are generally extracted by distillation, often by using steam. Other processes include expression, solvent extraction, sfumatura, absolute oil extraction, resin tapping, wax embedding, and cold pressing. They are used in perfumes, cosmetics, soaps, air fresheners and other products, for flavoring food and drink, and for adding scents to incense and household cleaning products.
Essential oil:
Essential oils are often used for aromatherapy, a form of alternative medicine in which healing effects are ascribed to aromatic compounds. Aromatherapy may be useful to induce relaxation, but there is not sufficient evidence that essential oils can effectively treat any condition. Improper use of essential oils may cause harm including allergic reactions, inflammation and skin irritation. Children may be particularly susceptible to the toxic effects of improper use. Essential oils can be poisonous if ingested or absorbed through the skin.
Production:
Distillation Most common essential oils such as lavender, peppermint, tea tree oil, patchouli, and eucalyptus are distilled. Raw plant material, consisting of the flowers, leaves, wood, bark, roots, seeds, or peel, is put into an alembic (distillation apparatus) over water. As the water is heated, the steam passes through the plant material, vaporizing the volatile compounds. The vapors flow through a coil, where they condense back to liquid, which is then collected in the receiving vessel.
Production:
Most oils are distilled in a single process. One exception is ylang-ylang (Cananga odorata) which is purified through a fractional distillation.
The recondensed water is referred to as a hydrosol, hydrolat, herbal distillate, or plant water essence, which may be sold as another fragrant product. Hydrosols include rose water, lavender water, lemon balm, clary sage, and orange blossom water.
Expression Most citrus peel oils are expressed mechanically or cold-pressed (similar to olive oil extraction). Due to the relatively large quantities of oil in citrus peel and low cost to grow and harvest the raw materials, citrus-fruit oils are cheaper than most other essential oils. Lemon or sweet orange oils are obtained as byproducts of the citrus industry.
Before the discovery of distillation, all essential oils were extracted by pressing.
Production:
Solvent extraction Most flowers contain too little volatile oil to undergo expression, but their chemical components are too delicate and easily denatured by the high heat used in steam distillation. Instead, a solvent such as hexane or supercritical carbon dioxide is used to extract the oils. Extracts from hexane and other hydrophobic solvents are called concretes, which are a mixture of essential oil, waxes, resins, and other lipophilic (oil-soluble) plant material.
Production:
Although highly fragrant, concretes contain large quantities of non-fragrant waxes and resins. Often, another solvent, such as ethyl alcohol, is used to extract the fragrant oil from the concrete. The alcohol solution is chilled to −18 °C (0 °F) for more than 48 hours which causes the waxes and lipids to precipitate out. The precipitates are then filtered out and the ethanol is removed from the remaining solution by evaporation, vacuum purge, or both, leaving behind the absolute.
Production:
Supercritical carbon dioxide is used as a solvent in supercritical fluid extraction. This method can avoid petrochemical residues in the product and the loss of some "top notes" when steam distillation is used. It does not yield an absolute directly. The supercritical carbon dioxide will extract both the waxes and the essential oils that make up the concrete. Subsequent processing with liquid carbon dioxide, achieved in the same extractor by merely lowering the extraction temperature, will separate the waxes from the essential oils. This lower temperature process prevents the decomposition and denaturing of compounds. When the extraction is complete, the pressure is reduced to ambient and the carbon dioxide reverts to a gas, leaving no residue.
Production:
Production quantities Estimates of total production of essential oils are difficult to obtain. One estimate, compiled from data in 1989, 1990, and 1994 from various sources, gives the following total production, in tonnes, of essential oils for which more than 1,000 tonnes were produced.
Uses and cautions:
Taken by mouth, many essential oils can be dangerous in high concentrations. Typical effects begin with a burning feeling, followed by salivation. Different essential oils may have drastically different pharmacology. Some act as local anesthetic counterirritants and, thereby, exert an antitussive (cough suppressing) effect. Many essential oils, particularly tea tree oil, may cause contact dermatitis. Menthol and some others produce a feeling of cold followed by a sense of burning.
Uses and cautions:
In Australia essential oils have been increasingly causing cases of poisoning, mostly of children. In the period 2014–2018 there were 4,412 poisoning incidents reported in New South Wales.
Use in aromatherapy:
Aromatherapy is a form of alternative medicine in which healing effects are ascribed to the aromatic compounds in essential oils and other plant extracts. Aromatherapy may be useful to induce relaxation, but there is not sufficient evidence that essential oils can effectively treat any condition. Scientific research indicates that essential oils cannot treat or cure any chronic disease or other illnesses. Much of the research on the use of essential oils for health purposes has serious methodological errors. In a systemic review of 201 published studies on essential oils as alternative medicines, only 10 were found to be of acceptable methodological quality, and even these 10 were still weak in reference to scientific standards. Use of essential oils may cause harm including allergic reactions and skin irritation; there has been at least one case of death.
Use as pesticide:
Research has shown that some essential oils have potential as a natural pesticide. In case studies, certain oils have been shown to have a variety of deterring effects on pests, specifically insects and select arthropods. These effects may include repelling, inhibiting digestion, stunting growth, decreasing rate of reproduction, or death of pests that consume the oil. However, the molecules within the oils that cause these effects are normally non-toxic for mammals. These specific actions of the molecules allow for widespread use of these "green" pesticides without harmful effects to anything else other than pests. Essential oils that have been investigated include rose, lemon grass, lavender, thyme, peppermint, basil, and eucalyptus.Although they may not be the perfect replacement for all synthetic pesticides, essential oils have prospects for crop or indoor plant protection, urban pest control, and marketed insect repellents, such as bug spray. Certain essential oils have been shown in studies to be comparable, if not exceeding, in effectiveness to DEET, which is currently marketed as the most effective mosquito repellent. Although essential oils are effective as pesticides when first applied in uses such as mosquito repellent applied to the skin, it is only effective in the vapor stage. Since this stage is relatively short-lived, creams and polymer mixtures are used in order to elongate the vapor period of effective repellency.In any form, using essential oils as green pesticides rather than synthetic pesticides has ecological benefits such as decreased residual actions. In addition, increased use of essential oils as pest control could have not only ecological, but economical benefits as the essential oil market diversifies and popularity increases among organic farmers and environmentally conscious consumers. As of 2012 some EOs are authorized, and in use, in the European Union: Melaleuca oil as a fungicide, citronella oil as a herbicide, Syzygium aromaticum oil as a fungicide and bactericide, Mentha spicata oil as a plant growth regulator; Citrus sinensis oil (only in France) for Bemisia tabaci on Cucurbita pepo and Trialeurodes vaporariorum on Solanum lycopersicum; and approvals for oils of Thymus, C. sinensis, and Tagetes as insecticides are pending.
Use in food:
In relation with their food applications, although these oils have been used throughout history as food preservatives, it was in the 20th century when EOs were considered as Generally Recognized as Safe (GRAS) by the Food and Drug Administration (FDA).GRAS substances according to the FDA As antimicrobials The most commonly used essential oils with antimicrobial action are: β-caryophyllene, eugenol, eugenol acetate, carvacrol, linalool, thymol, geraniol, geranyl acetate, bicyclogermacrene, cinnamaldehyde, geranial, neral, 1,8-cineole, methyl chavicol, methyl cinnamate, methyl eugenol, camphor, α-thujone, viridiflorol, limonene, (Z)-linalool oxide, α-pinene, p-cymene, (E)-caryophyllene, γ-terpinene.Some essential oils are effective antimicrobials and have been evaluated for food incorporation in vitro. However, actual deployment is rare because much higher concentrations are required in real foods. Some or all of this lower effectiveness is due to large differences between culture medium and foods in: chemistry (especially lipid content), viscosity, and duration of inoculation/storage.
Dilution:
Essential oils are usually lipophilic (literally: "oil-loving") compounds that are immiscible (not miscible) with water. They can be diluted in solvents like pure ethanol and polyethylene glycol.
Raw materials:
Essential oils are derived from sections of plants. Some plants, like the bitter orange, are sources of several types of essential oil.
Balsam of Peru Balsam of Peru, an essential oil derived from Myroxylon plants, is used in food and drink for flavoring, in perfumes and toiletries for fragrance, and in animal care products. However, national and international surveys identified balsam of Peru among the "top five" allergens most commonly causing patch test allergic reactions in people referred to dermatology clinics.
Garlic oil Garlic oil is an essential oil derived from garlic.
Raw materials:
Eucalyptus oil Most eucalyptus oil on the market is produced from the leaves of Eucalyptus globulus. Steam-distilled eucalyptus oil is used throughout Asia, Africa, Latin America and South America as a primary cleaning/disinfecting agent added to soaped mop and countertop cleaning solutions; it also possesses insect and limited vermin control properties. Note, however, there are hundreds of species of eucalyptus, and perhaps some dozens are used to various extents as sources of essential oils. Not only do the products of different species differ greatly in characteristics and effects, but also the products of the very same tree can vary grossly.
Raw materials:
Lavender oil Lavender oil has long been used in the production of perfume. However, studies have shown it can be estrogenic and antiandrogenic, causing problems for prepubescent boys and pregnant women, in particular. Lavender essential oil is also used as an insect repellent.
Rose oil Rose oil is produced from the petals of Rosa damascena and Rosa centifolia. Steam-distilled rose oil is known as "rose otto", while the solvent extracted product is known as "rose absolute".
Toxicity:
The potential toxicity of essential oil is related to its level or grade of purity, and to the toxicity of specific chemical components of the oil. Many essential oils are designed exclusively for their aroma-therapeutic quality; these essential oils generally should not be applied directly to the skin in their undiluted form. Some can cause severe irritation, provoke an allergic reaction and, over time, prove toxic to the liver. If ingested or rubbed into the skin, essential oils can be highly poisonous, causing confusion, choking, loss of muscle coordination, difficulty in breathing, pneumonia, seizures, and possibly severe allergic reactions or coma.Some essential oils, including many of the citrus peel oils, are photosensitizers, increasing vulnerability of the skin to sunlight.Industrial users of essential oils should consult the safety data sheets to determine the hazards and handling requirements of particular oils. Even certain therapeutic-grade oils can pose potential threats to individuals with epilepsy or pregnant women.
Toxicity:
Essential oil use in children can pose a danger when misused because of their thin skin and immature livers. This might cause them to be more susceptible to toxic effects than adults.
Flammability The flash point of each essential oil is different. Many of the common essential oils, such as tea tree, lavender, and citrus oils, are classed as Class 3 Flammable Liquids, as they have a flash point of 50–60 °C.
Toxicity:
Gynecomastia Estrogenic and antiandrogenic activity have been reported by in vitro study of tea tree oil and lavender essential oils. Two published sets of case reports suggest that lavender oil may be implicated in some cases of gynecomastia, an abnormal breast tissue growth in prepubescent boys. The European Commission's Scientific Committee on Consumer Safety dismissed the claims against tea tree oil as implausible, but did not comment on lavender oil. In 2018, a BBC report on a study stated that tea tree and lavender oils contain eight substances that when tested in tissue culture experiments, increasing the level of estrogen and decreasing the level of testosterone. Some of the substances are found in "at least 65 other essential oils". The study did not include animal or human testing.
Toxicity:
Handling Exposure to essential oils may cause contact dermatitis. Essential oils can be aggressive toward rubbers and plastics, so care must be taken in choosing the correct handling equipment. Glass syringes are often used, but have coarse volumetric graduations. Chemistry syringes are ideal, as they resist essential oils, are long enough to enter deep vessels, and have fine graduations, facilitating quality control. Unlike traditional pipettes, which have difficulty handling viscous fluids, the chemistry syringe, also known as a positive displacement pipette, has a seal and piston arrangement which slides inside the pipette, wiping the essential oil off the pipette wall.
Toxicity:
Ingestion Some essential oils qualify as GRAS flavoring agents for use in foods, beverages, and confectioneries according to strict good manufacturing practice and flavorist standards. Pharmacopoeia standards for medicinal oils should be heeded. Some oils can be toxic to some domestic animals, cats in particular. The internal use of essential oils can pose hazards to pregnant women, as some can be abortifacients in dose 0.5–10 mL, and thus should not be used during pregnancy.
Toxicity:
Pesticide residues Concern about pesticide residues in essential oils, particularly those used therapeutically, means many practitioners of aromatherapy buy organically produced oils. Not only are pesticides present in trace quantities, but also the oils themselves are used in tiny quantities and usually in high dilutions. Where there is a concern about pesticide residues in food essential oils, such as mint or orange oils, the proper criterion is not solely whether the material is organically produced, but whether it meets the government standards based on actual analysis of its pesticide content.
Toxicity:
Pregnancy Some essential oils may contain impurities and additives that may be harmful to pregnant women. Certain essential oils are safe to use during pregnancy, but care must be taken when selecting quality and brand. Sensitivity to certain smells may cause pregnant women to have adverse side effects with essential oil use, such as headache, vertigo, and nausea. Pregnant women often report an abnormal sensitivity to smells and taste, and essential oils can cause irritation and nausea when ingested.
Toxicity:
Toxicology The following table lists the LD50 or median lethal dose for common oils; this is the dose required to kill half the members of a tested animal population. LD50 is intended as a guideline only, and reported values can vary widely due to differences in tested species and testing conditions.
Standardization of derived products:
In 2002, ISO published ISO 4720 in which the botanical names of the relevant plants are standardized. The rest of the standards with regards to this topic can be found in the section of ICS 71.100.60
History:
The resins of aromatics and plant extracts were retained to produce traditional medicines and scented preparations, such as perfumes and incense, including frankincense, myrrh, cedarwood, juniper berry and cinnamon in ancient Egypt may have contained essential oils. In 1923, when archaeologists opened Pharaoh Tutankhamun’s tomb, they found 50 alabaster jars of essential oils.Essential oils have been used in folk medicine over centuries. The Persian physician Ibn Sina, known as Avicenna in Europe, was first to derive the fragrance of flowers from distillation, while the earliest recorded mention of the techniques and methods used to produce essential oils may be Ibn al-Baitar (1188–1248), an Arab Al-Andalusian (Muslim Spain) physician, pharmacist and chemist.Rather than refer to essential oils themselves, modern works typically discuss specific chemical compounds of which the essential oils are composed, such as referring to methyl salicylate rather than "oil of wintergreen".Essential oils are used in aromatherapy, a branch of alternative medicine that uses essential oils and other aromatic compounds. Oils are volatilized, diluted in a carrier oil and used in massage, diffused in the air by a nebulizer or diffuser, heated over a candle flame, or burned as incense. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Cab forward**
Cab forward:
The term cab forward locomotive refers to various rail and road vehicle designs that place the driver's compartment substantially farther towards the front than is common practice.
Rail locomotives:
In steam locomotive design, a cab forward design will typically have the driver's compartment or cab placed forward of the boiler at the very front of the engine. On a coal-fired locomotive, the fireman's station remains on the footplate behind the firebox so as to be next to the tender. On an oil-fired locomotive, the fireman's station could be (and normally is) in the forward cab. This type of design was widely, though not commonly, used throughout Europe in the first half of the 20th century, often in conjunction with an enclosed body design and/or streamlining.
Rail locomotives:
Visibility is greatly improved from the cab, and fumes from the chimney do not fill a forward cab in tunnels. However, the crew's prospects in the event of a collision are worse, and if the driver and fireman are in separate places it is difficult for them to communicate, just as in autotrains.
Rail locomotives:
Germany: Deutsche Reichsbahn In Germany, Borsig in Berlin built a one-off streamlined cab forward DRG Class 05 (serial number 05 003) 4-6-4 in 1937, with further development stopped by World War II. Fueled by pulverized coal and with the firebox at the forward end, this loco was built with huge driving wheels, 2300mm (90.55 in.) in diameter. The design speed was 175 km/h (109 mph), but its conventional layout sister 05 002 set a new world speed record for steam locomotives on 11 May 1936, after reaching 200.4 km/h (124.5 mph) on the Berlin–Hamburg line hauling a 197 t train, a record it lost two years later to the British LNER Class A4 4468 Mallard. In 1944, the streamlining was removed, but the 05 003 had by then already lost its cab forward layout. After the war, it pulled express trains in West Germany until 1958. It was scrapped in 1960.
Rail locomotives:
Italy: Ferrovie dello Stato italiane The state-owned Italian Ferrovie dello Stato had several cab forward locomotives, Class 670 and 671. These 4-6-0 engines had a three-axle tender, and were nicknamed "mucca" (cow). The engines (construction year 1902, top speed 110 km/h) were used to haul passenger trains on the Milan-Venice railway. A single Class 671 cab-forward was rebuilt as a Class 672 with a Franco-Crosti boiler in 1939.
Rail locomotives:
United States Forney design Matthias N. Forney was issued a patent in the late 1860s for a new locomotive design. He had set out to improve the factor of adhesion by putting as much of the boiler's weight as possible on the driving wheels, omitting the pilot wheels from beneath the front of the boiler. Such a design would not have been stable at high speeds on the rather uneven tracks which were common at the time. Instead, he extended the locomotive frame behind the cab, placing a four-wheel truck beneath the water tank and coal bunker. In conventional Whyte notation, this resulted in a 0-4-4T locomotive, but when run in reverse it was effectively a 4-4-0T, with the track stability of that popular wheel arrangement, along with unobstructed visibility for the engineer, and improved dispersal of smoke and steam.Forney's design proved ideal for the small, nimble locomotives for elevated and commuter railroads, and he licensed the patent design to many manufacturers. Large numbers of Forneys served in New York City, Boston, Chicago and elsewhere, but were superseded at the end of the nineteenth century by electrification and the development of subways.
Rail locomotives:
Ariel and Puck were 2 ft (610 mm) gauge locomotives built to the Forney cab-forward design for the Billerica and Bedford Railroad in 1877 by Hinkley Locomotive Works of Boston.
Rail locomotives:
Southern Pacific Railroad The best known example of the cab-forward design in the United States, the Southern Pacific Cab-Forward (also known to a lesser extent as "Cab-in-fronts" and "Cab-aheads") placed the cab at the front by the simple expedient of turning the entire locomotive, minus the tender, by 180 degrees. This arrangement was made possible by burning fuel oil instead of coal.
Rail locomotives:
The cab forward design was widely used by the Southern Pacific Railroad. The design was able to deal with the peculiar problems of its routes. The 39 long tunnels and nearly 40 miles (64 km) of snow sheds of the Sierra Nevada could funnel dangerous exhaust fumes back into the crew compartment of a conventional locomotive. After a number of crews nearly asphyxiated, the locomotive was run in reverse. This meant that the tender was leading the train, which introduced new problems. The tender blocked the view ahead and put crewmen on the wrong sides of the cab for seeing signals. The tenders were not designed to be pushed at the lead of the train, which limited speeds. Southern Pacific commissioned Baldwin Locomotive Works to build a prototype cab-forward locomotive, then ordered more units before the prototype had even arrived.
Rail locomotives:
All of the cab-forwards were oil-burning locomotives, which meant there was little trouble involved putting the tender at what would normally be the front of the locomotive. The oil and water tanks were pressurized so that both would flow normally even on uphill grades. Visibility from the cab was superb, such that one crewman could easily survey both sides of the track. There were concerns about what would happen to the crew in the event of a collision, and at least one fatal accident occurred on the Modoc Line in Herlong, California when a moving locomotive struck a flat car. Turning the normal locomotive arrangement around also placed the crew well ahead of the exhaust fumes, insulating them from that hazard. One problematic aspect of the design, however, was the routing of the oil lines; because the firebox was located ahead of the driving wheels (instead of behind them, the usual practice), oil leaks could cause the wheels to slip. A nuisance under most conditions, it resulted in at least one fatal accident. This occurred in 1941 when a cab-forward with leaking steam entered the tunnel at Santa Susana Pass, near Los Angeles. The tunnel was on a grade, and as the slow-moving train ascended the tunnel, water on the rails from a leaking cylinder cock caused the wheels to slip and spin. The train slipped backward and a coupler knuckle broke, separating the air line, causing an emergency brake application and stalling the train in a tunnel that was rapidly filling with exhaust fumes and steam. The oil dripping on the ties then ignited beneath the cab, killing the crew.No other North American railroad ordered cab-forward locomotives, although some, like Western Pacific, did consider the type. Built to deal with difficult terrain, these locomotives became an easily recognizable symbol of the Southern Pacific. In total 256 such Mallet-type articulated locomotives, in three different wheel arrangements, were placed on SP's roster. One example of the type, Southern Pacific 4294, is kept at the California State Railroad Museum in Sacramento, California. It is a 4-8-8-2 locomotive and is the only one to escape being scrapped. It was also SP's last new steam locomotive, built in 1944.
Rail locomotives:
A decade before SP's first cab forward, the North Pacific Coast Railroad, later part of the SP-owned Northwestern Pacific company, rebuilt an 1875 4-4-0 into an oil-fired cab-forward locomotive. This innovative engine was built by William (Bill) Thomas, the NPC master mechanic who was nationally known and holder of a number of patents. Thomas used the running gear and frame from NPC locomotive 5, the "Bodega", which had been wrecked in 1897, to build NPC 21. With the addition a new and unusual marine water tube boiler and an all-steel cab, installed in reverse order from standard engines, this unique creation earned Thomas a patent on the locomotive design. No. 21 entered service in 1900, but only lasted a few years. Although it reportedly steamed well, though with a sooty exhaust, the crews found it difficult to operate, and with fears of the possible results of a collision they dubbed it "The Freak". A negligent fireman allowed the water level to drop, damaging the boiler, and it was not repaired.
Rail locomotives:
Prussia Experimental Prussian T 16 (see in German) 2'C2' (4-6-4T) had control cabs at both ends.
UK: Southern Railway Oliver Bulleid's ill-fated Leader is sometimes referred to as a cab-forward locomotive, but since it had a cab at each end like a typical modern diesel or electric locomotive, this designation is not entirely appropriate.
Road transport:
Automobiles The cab forward design allows the passenger volume to be larger than in other similar sized automobiles.The first modern mass-produced U.S. automobile using the cab forward concept was the Pacer, introduced in 1975 by American Motors Corporation (AMC). The company did not call it "cab forward", but the Pacer's layout placed the passenger compartment farther forward than was typical to that time. Its A-pillars were moved forward and the windshield was placed over part of the engine compartment. The Pacer's "wide track and cab forward design actually lets it handle pretty well" given its body roll like competing contemporary models.Cab forward was used by Chrysler Corporation starting in 1992 to describe styling and engineering features that were similar to those seen on the AMC Pacer and the Lamborghini Portofino, which improved cornering and interior space The passenger cabin was "pushed forward" so that the front wheel well directly abutted the leading edge of the front doors, and the windshield extended forward over the engine, while the rear wheels were shifted towards the back corners of the vehicle. Moving the wheels to the edges allowed designers to enlarge the interior while improving ride and cornering.Numerous models built from 1993 to 2004 on the Chrysler LH platform, the JA and JR platforms ("cloud cars"), and the PL platform (Neon), were specifically marketed as cab forward cars. Chrysler claimed to be the first to apply these features to a full-size car. Likewise, the Dodge Stratus and Chrysler Cirrus have a hood that is wider than it is long because engineers established a goal of packing the engine and everything else that is located ahead of the passenger compartment into a much smaller space and then the designers developed the car's outer body to offer more interior roominess than competing models in their size class.
Road transport:
Commercial vehicles In road vehicle design, cab forward, also known as cab-over, COE (Cab Over Engine), or forward control, is a body style of truck, bus, or van that has a vertical front or "flat face", with the cab sitting above the front axle. This body design allows for a more compact configuration. For example, the Jeep Forward Control model was the first time the payload (or pickup box) had a record-breaking 74 in (1,880 mm) length (with the tailgate up) on an 81 in (2,057 mm) wheelbase as well as the first time offering a model where a 9-foot (274 cm) box exceeded the wheelbase of a truck.The cab forward truck configuration is currently common among European and Japanese truck manufacturers, because the laws governing overall vehicle lengths are strict and the body style allows longer trailers or a longer cargo area for the same overall length than a standard truck (with an engine compartment ahead of a conventional cabin). Better visibility and maneuverability in tight quarters, such as for city delivery, are benefits of locating the truck's cab up front. Large trucks of this type are most often described as cab over engine (COE) or cab over models. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**OmniFocus**
OmniFocus:
OmniFocus is a personal task manager by the Omni Group for macOS and iOS. The declared goal of the program is to be able to capture thoughts and ideas into to do lists. The program uses concepts and techniques described in the book and productivity system called Getting Things Done (GTD) by David Allen.
History:
OmniFocus has its roots in the Kinkless kGTD add/scripts for the Omni Group's OmniOutliner product. Kinkless (kGTD) was developed by Ethan J. A. Schoonover to enable those following the GTD methodology. The Omni Group subsequently brought Ethan along with Merlin Mann to form a project team to create the OmniFocus application.In 2018, version 3 of OmniFocus was released for iOS and macOS. With the release, the previous concept of contexts taken from GTD was replaced with tags.
Platforms:
macOS OmniFocus is available for macOS.
iOS OmniFocus is available on iOS (including the iPod Touch, iPhone, and iPad).
Android The Omni Group does not have plans to provide an Android application for OmniFocus. Google Play lists various third-party applications that interface with OmniFocus through the Omni Sync Server (e.g., Focus GTD).
Platforms:
Web application On January 26, 2018, Ken Case, CEO of the Omni Group, announced in the Omni Group forums that OmniFocus for the web is under development. It will not be a standalone version; it will only sync with existing databases set up with the macOS or iOS versions of OmniFocus. A subscription fee will be charged for access. In December 2018, Ken Case shared more details about the upcoming subscription service, where users could subscribe to get access to both the native OmniFocus apps and OmniFocus for the web, or just the latter with a reduced subscription fee. The option to make one-time purchases of the macOS and iOS apps will remain. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Frost crack**
Frost crack:
Frost crack or Southwest canker is a form of tree bark damage sometimes found on thin barked trees, visible as vertical fractures on the southerly facing surfaces of tree trunks. Frost crack is distinct from sun scald and sun crack and physically differs from normal rough-bark characteristics as seen in mature oaks, pines, poplars and other tree species.
Normal bark formation:
The sloughing or peeling of the bark is a normal process, especially in the spring when the tree begins to grow. The outer layers of the bark are dead tissue and therefore they cannot grow, the outer bark splitting in order for the tree to grow in circumference, increasing its diameter. The inner bark cambium and phloem tissues are living, and form a new protective layer of cells as the outer bark pulls apart.
Normal bark formation:
Normal furrowed bark has a layer of bark over the wood below, however bark may peel or fall off the tree in sheets (river birch), plates (sycamore and pine), strips (cedar) or blocks (dogwood).
Causes:
Frost cracks are frequently the result of some sort of weakness in the bark which occurred to the tree earlier. In late winter and early spring, water in the phloem, known as the inner bark and in the xylem, known as the wood, expands and contracts under often significantly fluctuating temperatures. Wood that is in some way damaged does not contract to the same degree as healthy wood. Rapid expansion and contraction of water within the wood and bark, particularly under rapidly falling night temperatures, can result in a frost crack, often accompanied by a loud explosive report.Research suggests that the main cause is actually 'frost-shrinkage' due to the freezing-out of cell wall moisture into lumens of wood cells. Other causes are the expansion of freezing water in cell lumens, and additionally the formation of ice lenses within wood. As stated, previous defects such as healed wounds, branch stubs, etc. in tree trunks function as stress raisers and trigger the frost cracking.In winter when the sun sets or the sky clouds over, the temperature of the tree drops very quickly and as the bark cools more quickly and the wood contracts more slowly, the bark rips open in a long crack, sometimes with an audible report likened to a rifle crack. Cold, clear, sunny days are the most likely to result in frost cracking, particularly as the heat energy from the low Sun on a Winter day can be higher than any other time of year.
Causes:
Trees that are growing in poorly drained sites are more subject to frost cracking than are those growing in drier, better drained soils. Trees suddenly left exposed by felling are highly susceptible.
Frost crack examples
Physical appearance:
Although frost cracks may be up to several metres long, these cracks usually only become apparent in early spring; they are often found on the southwest side of the tree. These cracks may heal in the summer and be reopen again in the winters, so that successive cracking and healing over a number of years results in the formation of 'frost ribs' on the sides of affected trees. The wood beneath the frost crack is rarely damaged. The cracks usually originate at the base of the trunk and extends from a metre to several metres upwards. Some discoloration is often found at the site of the damage.
Effect of damage:
Frost cracks often act as sites of entry for wood decay organisms, including insects, fungi and bacteria. Timber damaged in this way is unsuitable for use in buildings, etc.
Tree species susceptibility:
Species such as crab-apple, beech, walnut, oaks, maples, sycamore, horse-chestnut, willows and lime are prone to developing frost crack given the right conditions.
Prevention:
Avoiding the use of fertilizers late in the growing season can reduce the incidence of splits, also protecting the bark of young trees from physical damage such as that caused by lawn mowers, car bumpers, grazing animals, spades, trimmers, etc. Protect young trees in winter with paper tree wrap from ground level to the first main branches.
Repair:
Most tree species try to seal the edges of wounds by forming a callus. The wound's edges begin to form this callus during the first growing season after that crack appears and the callus layer will continue to grow and after many years, the wound may close over entirely. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Cochlea**
Cochlea:
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory organ of hearing, which is distributed along the partition separating the fluid chambers in the coiled tapered tube of the cochlea.
Cochlea:
The name cochlea derives from Ancient Greek κοχλίας (kokhlias) 'spiral, snail shell'.
Structure:
The cochlea (PL: cochleae) is a spiraled, hollow, conical chamber of bone, in which waves propagate from the base (near the middle ear and the oval window) to the apex (the top or center of the spiral). The spiral canal of the cochlea is a section of the bony labyrinth of the inner ear that is approximately 30 mm long and makes 23⁄4 turns about the modiolus. The cochlear structures include: Three scalae or chambers: the vestibular duct or scala vestibuli (containing perilymph), which lies superior to the cochlear duct and abuts the oval window the tympanic duct or scala tympani (containing perilymph), which lies inferior to the cochlear duct and terminates at the round window the cochlear duct or scala media (containing endolymph) a region of high potassium ion concentration that the stereocilia of the hair cells project into The helicotrema, the location where the tympanic duct and the vestibular duct merge, at the apex of the cochlea Reissner's membrane, which separates the vestibular duct from the cochlear duct The osseous spiral lamina, a main structural element that separates the cochlear duct from the tympanic duct The basilar membrane, a main structural element that separates the cochlear duct from the tympanic duct and determines the mechanical wave propagation properties of the cochlear partition The Organ of Corti, the sensory epithelium, a cellular layer on the basilar membrane, in which sensory hair cells are powered by the potential difference between the perilymph and the endolymph hair cells, sensory cells in the Organ of Corti, topped with hair-like structures called stereocilia The spiral ligament.The cochlea is a portion of the inner ear that looks like a snail shell (cochlea is Greek for snail). The cochlea receives sound in the form of vibrations, which cause the stereocilia to move. The stereocilia then convert these vibrations into nerve impulses which are taken up to the brain to be interpreted. Two of the three fluid sections are canals and the third is the 'Organ of Corti' which detects pressure impulses that travel along the auditory nerve to the brain. The two canals are called the vestibular canal and the tympanic canal.
Structure:
Microanatomy The walls of the hollow cochlea are made of bone, with a thin, delicate lining of epithelial tissue. This coiled tube is divided through most of its length by an inner membranous partition. Two fluid-filled outer spaces (ducts or scalae) are formed by this dividing membrane. At the top of the snailshell-like coiling tubes, there is a reversal of the direction of the fluid, thus changing the vestibular duct to the tympanic duct. This area is called the helicotrema. This continuation at the helicotrema allows fluid being pushed into the vestibular duct by the oval window to move back out via movement in the tympanic duct and deflection of the round window; since the fluid is nearly incompressible and the bony walls are rigid, it is essential for the conserved fluid volume to exit somewhere.
Structure:
The lengthwise partition that divides most of the cochlea is itself a fluid-filled tube, the third 'duct'. This central column is called the cochlear duct. Its fluid, endolymph, also contains electrolytes and proteins, but is chemically quite different from perilymph. Whereas the perilymph is rich in sodium ions, the endolymph is rich in potassium ions, which produces an ionic, electrical potential.
Structure:
The hair cells are arranged in four rows in the Organ of Corti along the entire length of the cochlear coil. Three rows consist of outer hair cells (OHCs) and one row consists of inner hair cells (IHCs). The inner hair cells provide the main neural output of the cochlea. The outer hair cells, instead, mainly 'receive' neural input from the brain, which influences their motility as part of the cochlea's mechanical "pre-amplifier". The input to the OHC is from the olivary body via the medial olivocochlear bundle.
Structure:
The cochlear duct is almost as complex on its own as the ear itself. The cochlear duct is bounded on three sides by the basilar membrane, the stria vascularis, and Reissner's membrane. The stria vascularis is a rich bed of capillaries and secretory cells; Reissner's membrane is a thin membrane that separates endolymph from perilymph; and the basilar membrane is a mechanically somewhat stiff membrane, supporting the receptor organ for hearing, the Organ of Corti, and determines the mechanical wave propagation properties of the cochlear system.
Function:
The cochlea is filled with a watery liquid, the endolymph, which moves in response to the vibrations coming from the middle ear via the oval window. As the fluid moves, the cochlear partition (basilar membrane and organ of Corti) moves; thousands of hair cells sense the motion via their stereocilia, and convert that motion to electrical signals that are communicated via neurotransmitters to many thousands of nerve cells. These primary auditory neurons transform the signals into electrochemical impulses known as action potentials, which travel along the auditory nerve to structures in the brainstem for further processing.
Function:
Hearing The stapes (stirrup) ossicle bone of the middle ear transmits vibrations to the fenestra ovalis (oval window) on the outside of the cochlea, which vibrates the perilymph in the vestibular duct (upper chamber of the cochlea). The ossicles are essential for efficient coupling of sound waves into the cochlea, since the cochlea environment is a fluid–membrane system, and it takes more pressure to move sound through fluid–membrane waves than it does through air. A pressure increase is achieved by reducing the area ratio from the tympanic membrane (drum) to the oval window (stapes bone) by 20. As pressure = force/area, results in a pressure gain of about 20 times from the original sound wave pressure in air. This gain is a form of impedance matching – to match the soundwave travelling through air to that travelling in the fluid–membrane system.
Function:
At the base of the cochlea, each 'duct' ends in a membranous portal that faces the middle ear cavity: The vestibular duct ends at the oval window, where the footplate of the stapes sits. The footplate vibrates when the pressure is transmitted via the ossicular chain. The wave in the perilymph moves away from the footplate and towards the helicotrema. Since those fluid waves move the cochlear partition that separates the ducts up and down, the waves have a corresponding symmetric part in perilymph of the tympanic duct, which ends at the round window, bulging out when the oval window bulges in.
Function:
The perilymph in the vestibular duct and the endolymph in the cochlear duct act mechanically as a single duct, being kept apart only by the very thin Reissner's membrane.
Function:
The vibrations of the endolymph in the cochlear duct displace the basilar membrane in a pattern that peaks a distance from the oval window depending upon the soundwave frequency. The Organ of Corti vibrates due to outer hair cells further amplifying these vibrations. Inner hair cells are then displaced by the vibrations in the fluid, and depolarise by an influx of K+ via their tip-link-connected channels, and send their signals via neurotransmitter to the primary auditory neurons of the spiral ganglion.
Function:
The hair cells in the Organ of Corti are tuned to certain sound frequencies by way of their location in the cochlea, due to the degree of stiffness in the basilar membrane. This stiffness is due to, among other things, the thickness and width of the basilar membrane, which along the length of the cochlea is stiffest nearest its beginning at the oval window, where the stapes introduces the vibrations coming from the eardrum. Since its stiffness is high there, it allows only high-frequency vibrations to move the basilar membrane, and thus the hair cells. The farther a wave travels towards the cochlea's apex (the helicotrema), the less stiff the basilar membrane is; thus lower frequencies travel down the tube, and the less-stiff membrane is moved most easily by them where the reduced stiffness allows: that is, as the basilar membrane gets less and less stiff, waves slow down and it responds better to lower frequencies. In addition, in mammals, the cochlea is coiled, which has been shown to enhance low-frequency vibrations as they travel through the fluid-filled coil. This spatial arrangement of sound reception is referred to as tonotopy.
Function:
For very low frequencies (below 20 Hz), the waves propagate along the complete route of the cochlea – differentially up vestibular duct and tympanic duct all the way to the helicotrema. Frequencies this low still activate the Organ of Corti to some extent but are too low to elicit the perception of a pitch. Higher frequencies do not propagate to the helicotrema, due to the stiffness-mediated tonotopy.
Function:
A very strong movement of the basilar membrane due to very loud noise may cause hair cells to die. This is a common cause of partial hearing loss and is the reason why users of firearms or heavy machinery often wear earmuffs or earplugs.
Function:
Hair cell amplification Not only does the cochlea "receive" sound, a healthy cochlea generates and amplifies sound when necessary. Where the organism needs a mechanism to hear very faint sounds, the cochlea amplifies by the reverse transduction of the OHCs, converting electrical signals back to mechanical in a positive-feedback configuration. The OHCs have a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds.The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions).
Function:
Otoacoustic emissions Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions are important in some types of tests for hearing impairment, since they are present when the cochlea is working well, and less so when it is suffering from loss of OHC activity.
Function:
Role of gap junctions Gap-junction proteins, called connexins, expressed in the cochlea play an important role in auditory functioning. Mutations in gap-junction genes have been found to cause syndromic and nonsyndromic deafness. Certain connexins, including connexin 30 and connexin 26, are prevalent in the two distinct gap-junction systems found in the cochlea. The epithelial-cell gap-junction network couples non-sensory epithelial cells, while the connective-tissue gap-junction network couples connective-tissue cells. Gap-junction channels recycle potassium ions back to the endolymph after mechanotransduction in hair cells. Importantly, gap junction channels are found between cochlear supporting cells, but not auditory hair cells.
Clinical significance:
Hearing loss Bionics In 2009, engineers at the Massachusetts Institute of Technology created an electronic chip that can quickly analyze a very large range of radio frequencies while using only a fraction of the power needed for existing technologies; its design specifically mimics a cochlea.
Other animals:
The coiled form of cochlea is unique to mammals. In birds and in other non-mammalian vertebrates, the compartment containing the sensory cells for hearing is occasionally also called "cochlea," despite not being coiled up. Instead, it forms a blind-ended tube, also called the cochlear duct. This difference apparently evolved in parallel with the differences in frequency range of hearing between mammals and non-mammalian vertebrates. The superior frequency range in mammals is partly due to their unique mechanism of pre-amplification of sound by active cell-body vibrations of outer hair cells. Frequency resolution is, however, not better in mammals than in most lizards and birds, but the upper frequency limit is – sometimes much – higher. Most bird species do not hear above 4–5 kHz, the currently known maximum being ~ 11 kHz in the barn owl. Some marine mammals hear up to 200 kHz. A long coiled compartment, rather than a short and straight one, provides more space for additional octaves of hearing range, and has made possible some of the highly derived behaviors involving mammalian hearing.As the study of the cochlea should fundamentally be focused at the level of hair cells, it is important to note the anatomical and physiological differences between the hair cells of various species. In birds, for instance, instead of outer and inner hair cells, there are tall and short hair cells. There are several similarities of note in regard to this comparative data. For one, the tall hair cell is very similar in function to that of the inner hair cell, and the short hair cell, lacking afferent auditory-nerve fiber innervation, resembles the outer hair cell. One unavoidable difference, however, is that while all hair cells are attached to a tectorial membrane in birds, only the outer hair cells are attached to the tectorial membrane in mammals.
History:
The name cochlea is derived from the Latin word for snail shell, which in turn is from the Greek κοχλίας kokhlias ("snail, screw"), from κόχλος kokhlos ("spiral shell") in reference to its coiled shape; the cochlea is coiled in mammals with the exception of monotremes. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Masonic chess**
Masonic chess:
Masonic chess is a chess variant invented by George R. Dekle Sr. in 1983. The game is played on a modified chessboard whereby even-numbered ranks are indented to the right—resembling masonry brickwork. The moves of the pieces are adapted to the new geometry; in other respects the game is the same as chess.
Masonic chess was included in World Game Review No. 10 edited by Michael Keller.
Board characteristics:
The Masonic board cells are slightly rectangular, and indentation of alternating ranks results in cants (oblique files) 30° from the vertical and diagonals 30° from the horizontal, the same as hexagon-based chessboards when cell vertices face the players. (For example, rooks have six directions of movement, and Masonic pawns move and capture the same as pawns in De Vasa's hexagonal chess. Masonic bishops, however, are limited to the four diagonal directions to the sides.) As with hex-based boards, three colors are used, so no two adjacent cells are the same color, and gameboard diagonals are highlighted.
Game rules:
The diagram shows the starting setup. All normal chess rules apply, including conventions for castling either kingside or queenside, a pawn's initial two-step option, en passant captures, promotion, and so on, but the pieces have specially defined moves.
Piece moves A rook moves along the rank (two directions) and cants (four directions).
A bishop moves on diagonals to the sides (four directions), or one step as a rook (six directions).
The queen moves as a rook and bishop. (Ten directions.) The king moves one step as a queen.
A knight moves in the pattern: one step as a rook, then one step diagonally in the same (forward, backward, or sideways) direction. A knight leaps any intervening men.
A pawn moves one step forward as a rook; on its first move it may optionally move two steps forward in the same direction. A pawn captures one step diagonally forward; en passant captures are permitted.
Piece moves illustrated | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Control-X**
Control-X:
In computing, Control+x is the key combination of the control key and a key usually labeled "x" (lower-case letter ex), typically used to cut selected text and save it to the clipboard ready to paste elsewhere. Conventionally, the key combination is produced by holding down Control and x simultaneously. To avoid having to press multiple keys simultaneously, the key combination is, on some systems, entered by first pushing the control key and then the X key.
Text editing:
In many software applications on Windows and the X Window System Control+x can be used to cut highlighted mutable text to the clipboard. On Mac OS X ⌘ Command+x has an analogous function. The key combination was one of a handful of keyboard sequences chosen by the program designers at Xerox PARC to control text editing.For historical reasons, the control character CAN may be referred to as ^X.
Interaction style:
In computer science, this style of interaction is referred to as indirect manipulation, a human–computer interaction style, as opposed to direct manipulation. Direct manipulation is a term introduced by Ben Shneiderman in 1982 within the context of office applications and the desktop metaphor.Indirect manipulation has a higher level of abstraction compared to direct manipulation, because first one must select the item (such as character, word, paragraph or icon) that one wants to edit and then give the command; in this case, the cut command by pressing the key combination Control+x | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Hydraulic Launch Assist**
Hydraulic Launch Assist:
Hydraulic Launch Assist (HLA) is the name of a hydraulic hybrid regenerative braking system for land vehicles produced by the Eaton Corporation.
Background:
The HLA system recycles energy by converting kinetic energy into potential energy during deceleration via hydraulics, storing the energy at high pressure in an accumulator filled with nitrogen gas. The energy is then returned to the vehicle during subsequent acceleration thereby reducing the amount of work done by the internal combustion engine. This system provides considerable increase in vehicle productivity while reducing fuel consumption in stop-and-go use profiles like refuse vehicles and other heavy duty vehicles.
Parallel vs. series hybrids:
The HLA system is called a parallel hydraulic hybrid. In parallel systems the original vehicle drive-line remains, allowing the vehicle to operate normally when the HLA system is disengaged. When the HLA is engaged, energy is captured during deceleration and released during acceleration, in contrast to series hydraulic hybrid systems which replace the entire traditional drive-line to provide power transmission in addition to regenerative braking.
Hydraulic vs. electric hybrids:
Hydraulic hybrids are said to be power dense, while electric hybrids are energy dense. This means that electric hybrids, while able to deliver large amounts of energy over long periods of time are limited by the rate at which the chemical energy in the batteries is converted to mechanical energy and vice versa. This is largely governed by reaction rates in the battery and current ratings of associated components. Hydraulic hybrids on the other hand are capable of transferring energy at a much higher rate, but are limited by the amount of energy that can be stored. For this reason, hydraulic hybrids lend themselves well to stop-and-go applications and heavy vehicles.
Applications:
Concept vehicles Ford Motor Company included the HLA system in their 2002 F-350 Tonka truck concept vehicle, reported to have lower emissions and better fuel economy than any V-8 diesel truck engine of the time, with HLA designed to eventually improve fuel economy by 25%-35% in heavy truck city driving.
Shuttle bus Eaton, Ford, the US Army, and IMPACT Engineering, Inc. (of Kent, Washington), built an E-450 shuttle bus as part of the Army's HAMMER (Hydraulic Hybrid Advanced Materials Multifuel Engine Research) project.
Refuse Eaton has been awarded the Texas government’s New Technology Research and Development grant to build 12 refuse vehicles with HLA systems.Peterbilt Motors has designed a Model 320 chassis that incorporates the HLA system, which was featured on the cover of the December 13, 2007, issue of Machine Design. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Romal**
Romal:
A Romal (pronounced ro-MAHL), is a type of long quirt attached to the end of a set of closed reins that are connected to the bridle of a horse. It is not to be used to strike a horse, but rather was a tool used to assist in moving cattle.
A romal is usually made of leather or rawhide, is about four to five feet long, flexible and somewhat heavy, to prevent excess swinging and to aid control.
Romal:
It is historically associated with the vaquero tradition of western riding, and today is most often seen in western pleasure and equitation classes at horse shows for certain horse breeds that are shown in the "California style" of western riding, or in other western events in regions of the United States and Canada that are most influenced by the vaquero style. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Gamvas**
Gamvas:
Gamvas is a 2D HTML5 game engine for the canvas element. Gamvas tries to reduce low level tasks for the developer by providing a general game programming framework with game states, actors, actor states, cameras and Box2D physics integration. It is developed by the author of the MIT licensed C/C++ game engine Sge2d and shares many ideas with it.
Licensing:
As of June 7, 2012 Gamvas is available under open source MIT license without feature limitation. Before this it was available in a lite version free for non commercial use and a pro version with enhanced features and the right to use it in commercial projects.
Example:
The following example is a very basic hello world running with a constant frame rate: | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Self bow**
Self bow:
A self bow or simple bow is a bow made from a single piece of wood. Extra material such as horn nocks on the ends, or built-up handles, would normally be accepted as part of a self bow. Some modern authorities would also accept a bow spliced together in the handle from two pieces of wood.
Comparison with composite bows:
An effective self bow can be made from widely available local material in most inhabited parts of the world, with limited tools whose functions include chopping, shaving, and scraping. A day of work may be needed, starting with a seasoned stave; a composite bow requires a week's work, and could possibly take up to several years, starting with a much greater range of materials and skills. Self bows must be approximately the height of the archer if they are to allow a long draw, and they are less efficient in the specialized art of flight archery. Well-designed composite bows of high draw-weight give higher arrow velocity, and the bow itself is shorter. However, the hide glue that holds a composite bow together absorbs water and will dissolve if soaked; the wood of self bows is less sensitive to humidity. At the weights more usual for modern amateurs, the greater density of horn and sinew compared to wood usually cancels any advantage of composite construction. For most practical non-mounted archery purposes, self bows can perform as well as composite; "the initial velocity is about the same for all types of bow… within certain limits"
History:
In many parts of the world including much of Africa, the Americas, northern Europe, and Southern Asia, the great majority of traditional bows are self bows. The first bow artifacts, the Stellmoor and Holmegaard artifacts of Northern Europe, are self bows. The Stellmoor bow was made from the heartwood of a Scots pine while the oldest Holmegaard bows were carved from small-diameter elms. In primitive flight archery competitions, bows inspired by the design of the Holmegaard bows perform very well because of their light, non-bending tips.
Selecting wood:
In most inhabited areas, common timbers can be made into high-quality self bows. The pieces must be long enough (approximately the height of the archer), and the grain must be sufficiently straight. Denser timbers normally store energy better and can be made into narrower bows with less effort – high-quality yew allows for particularly narrow self bows, such as the traditional European version of the longbow. The Eastern Woodlands tribes of North America used hickory, tribes in parts of the Midwestern United States osage orange, Native Americans of the west coast used short, wide, recurved bows made of American Pacific yew, Brazilian rainforest tribes used palm wood, and many others. In Europe and North America, common woods such as maple, ash, elm, and oak make excellent flat bows, and are far easier to obtain than good-quality yew. The fibres on the back of a self bow must be, so far as possible, continuous. This may be achieved by using the outer, under-bark surface of the tree as the back of the bow (convenient with most white woods), or by the painstaking process of removing outer growth rings (often used with yew and osage orange), or by making or following a cut or split surface which happens to have continuous grain (a usual approach if starting with commercially sawn wood). The density of timber correlates well with its ability to store energy as it is bent. Denser timbers can make narrower bows. The same design for less dense timbers results in the bow taking excessive set-string follow, or even breaking. However, equally effective bows may be made from less dense timber by making them wider near the centre. The mass of equivalent bows is closely similar whatever the density of wood; approximately the same mass of wood is required whatever the density of the timber.
Selecting wood:
The overall length of bending wood must be about 2.3 times the draw length. Narrow bows (known as "longbows") can bend in the handle. Wider bows (known as "flatbows") must be narrow in the handle if they are to be practical, but the handle must be made thicker so as not to bend, and the complete bow will therefore tend to be longer.
Selecting wood:
Self bows may be of any side-view profile; moderate recurving can often be achieved with heat and force. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Dynamic routing**
Dynamic routing:
Dynamic routing, also called adaptive routing, is a process where a router can forward data via a different route for a given destination based on the current conditions of the communication circuits within a system. The term is most commonly associated with data networking to describe the capability of a network to 'route around' damage, such as loss of a node or a connection between nodes, as long as other path choices are available. Dynamic routing allows as many routes as possible to remain valid in response to the change.
Dynamic routing:
Systems that do not implement dynamic routing are described as using static routing, where routes through a network are described by fixed paths. A change, such as the loss of a node, or loss of a connection between nodes, is not compensated for. This means that anything that wishes to take an affected path will either have to wait for the failure to be repaired before restarting its journey, or will have to fail to reach its destination and give up the journey.
All Protocols:
There are several protocols that can be used for dynamic routing. Routing Information Protocol (RIP) is a distance-vector routing protocol that prevents routing loops by implementing a limit on the number of hops allowed in a path from source to destination. Open Shortest Path First (OSPF) uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs). Intermediate System to Intermediate System (IS-IS) determines the best route for data through a packet-switched network. Interior Gateway Routing Protocol (IGRP) and its advanced form Enhanced Interior Gateway Routing Protocol (EIGRP) are used by routers to exchange routing data within an autonomous system.
Alternate paths:
Many systems use some next-hop forwarding protocol—when a packet arrives at some node, that node decides on-the-fly which link to use to push the packet one hop closer to its final destination.
Routers that use some adaptive protocols, such as the Spanning Tree Protocol, in order to "avoid bridge loops and routing loops", calculate a tree that indicates the one "best" link for a packet to get to its destination.
Alternate "redundant" links not on the tree are temporarily disabled—until one of the links on the main tree fails, and the routers calculate a new tree using those links to route around the broken link.
Routers that use other adaptive protocols, such as grouped adaptive routing, find a group of all the links that could be used to get the packet one hop closer to its final destination.
The router sends the packet out any link of that group which is idle.
The link aggregation of that group of links effectively becomes a single high-bandwidth connection.
Outside of computer networks:
Contact centres employ dynamic routing based on the customer's enquiry and agent's skills to increase the operational efficiency of the call handling by agents, which boosts both agent and customer satisfaction. This adaptive strategy is known as omnichannel.Dynamic routing in found the brain in relation between sensory and mnemonic signals and decision making, and is a subject of studies in neuroscience.People using public transport also exhibit dynamic routing behaviour. For example, if a local railway station is closed, people can alight from the train at a different station and use a bus to reach their destination. Yet another example of dynamic routing can be seen within financial markets. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**CYP2W1**
CYP2W1:
CYP2W1 (cytochrome P450, family 2, subfamily W, polypeptide 1) is a protein that in humans is encoded by the CYP2W1 gene.This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. CYP2W1 is an interesting enzyme since it is mainly expressed in tumors and not in normal human tissue. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Transductor**
Transductor:
A transductor is type of magnetic amplifier used in power systems for compensating reactive power. It consists of an iron-cored inductor with two windings - a main winding through which an alternating current flows from the power system, and a secondary control winding which carries a small direct current. By varying the direct current, the iron core of the transductor can be arranged to saturate at different levels and thus vary the amount of reactive power absorbed.
Transductor:
Transductors were widely used before the advent of solid-state electronics but today have been largely replaced by power electronic devices such as the Static VAR compensator and STATCOM.
Transductor:
A formerly common use for Transductors was in CRT displays, to correct a distortion called pincushion distortion, where the side of the picture bowed in at the centre as a result of the geometry of large deflection angles. It would have one set of windings in the horizontal deflection circuit and the other set in the vertical; the action of the transductor caused the deflection waveforms to modulate each other - reducing line scan at the top and bottom (where the magnetization from the vertical deflection waveform was greatest) and similarly on the vertical waveform (where the magnetization from horizontal scan current was greatest).An additional use for the transductor, prior to Hall effect devices, was as a feedback transducer for large dc current measurement. The dc bus to be measured passed through the center of the toroidal iron core saturable reactor and 120vac excitation was applied to the winding around the iron core. As the current in the dc bus increased, the iron saturated more and more, which in turn allowed a higher level of ac current to flow. This ac current was then rectified as an output signal proportional to the bus current. In this manner, dc currents of 30,000 amps or more could be accurately measured without electrically bonding to the bus. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Fibrolamellar hepatocellular carcinoma**
Fibrolamellar hepatocellular carcinoma:
Fibrolamellar carcinoma (FLC) is a rare form of carcinoma that typically affects young adults and is characterized, under the microscope, by laminated fibrous layers interspersed between the tumor cells. It has been estimated that 200 new cases are diagnosed worldwide each year. However, in light of recent advances in our molecular understanding, this has recently been revised to suggest it may be at least ten times more common. FLC, also known as fibrolamellar hepatocellular carcinoma, is different from the more common hepatocellular carcinoma (HCC) in that it afflicts young people with normal liver function and no known risk factors.
Cause:
A 2014 study showed the presence of the DNAJB1-PRKACA chimeric transcript (resulting from a 400kb somatic deletion on chromosome 19) in 100% of the FLCs examined (15/15). This gene fusion has been confirmed in many other studies. That this genomic deletion is sufficient to produce FLC was shown by creating this deletion, and formation of the DNAJB1::PRKACA chimeric gene, using CRISPR/Cas9 in the livers of mice. That the actual formation of the DNAJB1::PRKACA was responsible, and not the deletion, was shown by expression of the DNAJB1::PRKACA from a transposon.
Cause:
To determine if the DNAJB1::PRKACA was only involved in triggering the tumor, or if it continued to drive the tumor, a small hairpin RNA was used to eliminate the DNAJB1::PRKACA. The tumors died, which demonstrated not only that DNAJB1::PRKACA is continuing to drive FLC, but that the tumor has become oncogenically addicted.
Pathology:
The histopathology of FLC is characterized by laminated fibrous layers, interspersed between the tumor cells. Cytologically, the tumor cells have a low nuclear to cytoplasmic ratio with abundant eosinophilic cytoplasm. Tumors are non-encapsulated, but well circumscribed, when compared to conventional HCC (which typically has an invasive border).
Diagnosis:
Due to lack of symptoms, until the tumor is sizable, this form of cancer is often advanced when diagnosed. Symptoms include vague abdominal pain, nausea, abdominal fullness, malaise and weight loss. They may also include a palpable liver mass. Other presentations include jaundice, ascites, fulminant liver failure, encephalopathy, gynecomastia (males only), thrombophlebitis of the lower limbs, recurrent deep vein thrombosis, anemia and hypoglycemia.The usual markers for liver disease – aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase – are often normal or only slightly elevated. FLC often does not produce alpha fetoprotein (AFP), a widely used marker for conventional hepatocellular carcinoma. In a subset of FLC patients elevated plasma neurotensin levels may be present. Likewise, in a subset of FLC patients, elevated serum vitamin B12 binding globulin levels may be present.Diagnosis is normally made by imaging (ultrasound, CT or MRI) and biopsy. However, even with a biopsy, there is often disagreement over the diagnosis. Since the characterization of the DNAJB1::PRKACA fusion, the most reliable diagnosis is through molecular characterization such as PCR to detect the fusion, or genomic sequencing, or using a fluorescent in-situ hybridization.
Treatment:
FLC can often be surgically removed. Liver resection is the optimal treatment and may need to be performed more than once, since this disease has a very high recurrence rate. Due to such recurrence, periodic follow-up medical imaging (CT or MRI) is necessary.When the tumor cannot be removed surgically or when there is distant spread, many different systemic therapies are currently being used to treat the disease. However, no standard of care currently exists for FLC. Consequently, there remains a pressing need to identify proven, effective systemic therapies for the cancer. Radiotherapy has been used but data is limited concerning its use. The Fibrolamellar Registry, (http://fibroregistry.org) a patient and family run medical registry has collected data from over 250 patients. This work has been used in multiple publications which include extended information on patient outcomes, efficacy of immune checkpoint inhibitors, efficacy of specific drugs and understanding the basis of high ammonia in FLC.The Fibroregistry has answers to frequently asked questions (https://fibroregistry.org/faq-fibrolamellar/ ) as well as plain-language summaries of the science literature for understanding the success rate of some treatment approaches (https://fibroregistry.org/published-papers/ ). The FibroFoundation has resources available on different FLC treatment options. The survival rate for FLC largely depends on whether (and to what degree) the cancer has metastasized, i.e. spread to the lymph nodes or other organs. Distant spread (metastases), significantly reduces the median survival rate. Five-year survival rates vary between 40–90%.
Epidemiology:
FLC accounts for 1–10% of primary liver cancers. It typically has a young age at presentation when compared to conventional HCC. Previously it was estimated to be 20-40 years, mean ages 27 years, but when analysis is restricted to those patients who are confirmed with a molecular test to have FLC, the age range is 10-40 and mean age of 21 years. Unlike the more common HCC, patients most often do not have coexistent liver disease such as cirrhosis.
History:
This disease was first described by Hugh Edmondson in a 14-year-old female with no underlying liver disease. The name fibrolamellar hepatocellular carcinoma was coined by Craig et al. in 1980. It was not recognized as a distinct form of cancer by the WHO until 2010.Starting in 2010, some patients and their family members started to examine the molecular basis of FLC. They gathered samples through social media, sequenced the genome, and analyzed the immunological response. Since there are few patients at any one institution, they formed their own medical registry, which allowed them to follow patients as they changed institutions (http://fibroregistry.org). This work led to the identification of the chimeric fusion driver and the first characterization of the transcriptome and proteome. The work was heralded by Francis Collins when he presented to the Senate Appropriations committee and was used by President Obama at the launch of The Precision Medicine Initiative at the White House. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Chinese Chemical Letters**
Chinese Chemical Letters:
Chinese Chemical Letters is a monthly peer-reviewed scientific journal covering all aspects of chemistry. It was established in 1990 and is published by Elsevier on behalf of the Chinese Chemical Society. The editor-in-chief is Xu-Hong Qian (East China University of Science and Technology).
Abstracting and indexing:
The journal is abstracted and indexed in: Chemical Abstracts Service Science Citation Index Expanded ScopusAccording to the Journal Citation Reports, the journal has a 2020 impact factor of 4.632.
{cite web |url=https://www.journals.elsevier.com/chinese-chemical-letters}
Coercive citations:
In 2015, it was reported by Jeffrey Beall that the journal offered to waive their article processing charge for authors whose articles would be cited more than 6 times (apparently including self-citations) in the first two years after publication. This practice is known as coercive citation. In a reaction, the editorial office stated that this episode "was totally due to the inappropriate English expression of our newly joined editor" and that "[t]he publication fee waiver based on the citations has been eliminated." | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**Drostanolone**
Drostanolone:
Drostanolone, or dromostanolone, is an anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. An androgen ester prodrug of drostanolone, drostanolone propionate, was formerly used in the treatment of breast cancer in women under brand names such as Drolban, Masteril, and Masteron. This has also been used non-medically for physique- or performance-enhancing purposes.
Pharmacology:
Pharmacodynamics Like other AAS, drostanolone is an agonist of the androgen receptor (AR). It is not a substrate for 5α-reductase and is a poor substrate for 3α-hydroxysteroid dehydrogenase (3α-HSD), and therefore shows a high ratio of anabolic to androgenic activity. As a DHT derivative, drostanolone is not a substrate for aromatase and hence cannot be aromatized into estrogenic metabolites. While no data are available on the progestogenic activity of drostanolone, it is thought to have low or no such activity similarly to other DHT derivatives. Since the drug is not 17α-alkylated, it is not known to cause hepatotoxicity.
Chemistry:
Drostanolone, also known as 2α-methyl-5α-dihydrotestosterone (2α-methyl-DHT) or as 2α-methyl-5α-androstan-17β-ol-3-one, is a synthetic androstane steroid and a derivative of DHT. It is specifically DHT with a methyl group at the C2α position.
History:
Drostanolone and its ester drostanolone propionate were first described in 1959. Drostanolone propionate was first introduced for medical use in 1961.
Society and culture:
Generic names Drostanolone is the generic name of the drug and its INN, BAN, and DCF. It has also been referred to as dromostanolone.
Legal status Drostanolone, along with other AAS, is a schedule III controlled substance in the United States under the Controlled Substances Act.
Synthesis:
Bolazine is when react 2 eq. with hydrazine to give dimer Treatment of DHT (androstan-17β-ol-3-one, stanolone) [521-18-6] (1) with methyl formate and the strong base sodium methoxide gives [4033-95-8] (2). The newly added formyl function in the product is shown in the enol form. Catalytic hydrogenation reduces that function to a methyl group (3). The addition of hydrogen from the bottom face of the molecule leads to the formation of β-methyl isomer where the methyl group occupies the higher-energy axial position. Strong base-induced equilibration of the methyl group leads to the formation of the sterically favoured equatorial α-methyl isomer, affording dromostanolone (4). | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
**FCX file compression**
FCX file compression:
FCX file compression is a file compression utility and file format. It is supported on a large number of platforms. It is published by Compact Data Works and was originally released in 1988 for VAX/VMS. | kaggle.com/datasets/mbanaei/all-paraphs-parsed-expanded |
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