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49,248,145 | https://en.wikipedia.org/wiki/Jellyfish%20galaxy | A jellyfish galaxy is a type of galaxy found in galaxy clusters. They are characterised by ram pressure stripping of gas from the affected galaxy by the intracluster medium, triggering starbursts along a tail of gas.
Jellyfish galaxies have been seen in a number of galaxy clusters including the Hydra Cluster, Abell 2125 (redshift z=0.20; ACO 2125 C153); Abell 2667 (z=0.23; G234144−260358); Abell 2744 (z=0.31; ACO 2744 Central Jellyfish; HLS001427–30234/ACO 2744 F0083; GLX001426–30241 / ACO 2744 F0237 / ACO 2733 CN104; MIP001417–302303 / ACO 2744 F1228; HLS001428–302334; GLX001354–302212 ).
Examples
References
Galaxies | Jellyfish galaxy | [
"Astronomy"
] | 216 | [
"Galaxies",
"Astronomical objects"
] |
49,248,459 | https://en.wikipedia.org/wiki/Transactivation%20domain | The transactivation domain or trans-activating domain (TAD) is a transcription factor scaffold domain which contains binding sites for other proteins such as transcription coregulators. These binding sites are frequently referred to as activation functions (AFs). TADs are named after their amino acid composition. These amino acids are either essential for the activity or simply the most abundant in the TAD. Transactivation by the Gal4 transcription factor is mediated by acidic amino acids, whereas hydrophobic residues in Gcn4 play a similar role. Hence, the TADs in Gal4 and Gcn4 are referred to as acidic or hydrophobic, respectively.
In general we can distinguish four classes of TADs:
acidic domains (called also “acid blobs” or “negative noodles", rich in D and E amino acids, present in Gal4, Gcn4 and VP16).
glutamine-rich domains (contains multiple repetitions like "QQQXXXQQQ", present in SP1)
proline-rich domains (contains repetitions like "PPPXXXPPP" present in c-jun, AP2 and Oct-2)
isoleucine-rich domains (repetitions "IIXXII", present in NTF-1)
Alternatively, since similar amino acid compositions does not necessarily mean similar activation pathways, TADs can be grouped by the process they stimulate, either initiation or elongation.
Acidic/9aaTAD
Nine-amino-acid transactivation domain (9aaTAD) defines a domain common to a large superfamily of eukaryotic transcription factors represented by Gal4, Oaf1, Leu3, Rtg3, Pho4, Gln3, Gcn4 in yeast, and by p53, NFAT, NF-κB and VP16 in mammals. The definition largely overlaps with an "acidic" family definition. A 9aaTAD prediction tool is available. 9aaTADs tend to have an associated 3-aa hydrophobic (usually Leu-rich) region immediately to its N-terminal.
9aaTAD transcription factors p53, VP16, MLL, E2A, HSF1, NF-IL6, NFAT1 and NF-κB interact directly with the general coactivators TAF9 and CBP/p300. p53 9aaTADs interact with TAF9, GCN5 and with multiple domains of CBP/p300 (KIX, TAZ1,TAZ2 and IBiD).
The KIX domain of general coactivators Med15(Gal11) interacts with 9aaTAD transcription factors Gal4, Pdr1, Oaf1, Gcn4, VP16, Pho4, Msn2, Ino2 and P201. Positions 1, 3-4, and 7 of the 9aaTAD are the main residues that interact with KIX. Interactions of Gal4, Pdr1 and Gcn4 with Taf9 have been observed. 9aaTAD is a common transactivation domain which recruits multiple general coactivators TAF9, MED15, CBP/p300 and GCN5.
Glutamine-rich
Glutamine (Q)-rich TADs are found in POU2F1 (Oct1), POU2F2 (Oct2), and Sp1 (see also Sp/KLF family). Although such is not the case for every Q-rich TAD, Sp1 is shown to interact with TAF4 (TAFII 130), a part of the TFIID assembly.
See also
DNA-binding protein
Transcription factor
References
External links
9aaTAD prediction tool
Transcription factors
Protein domains | Transactivation domain | [
"Chemistry",
"Biology"
] | 790 | [
"Transcription factors",
"Gene expression",
"Protein classification",
"Signal transduction",
"Protein domains",
"Induced stem cells"
] |
49,249,936 | https://en.wikipedia.org/wiki/Drug%20vectorization | In pharmacology and medicine, vectorization of drugs refers to (intracellular) targeting with plastic, noble metal or silicon nanoparticles or liposomes to which pharmacologically active substances are reversibly bound or attached by adsorption.
CNRS researchers have devised a way to overcome the problem of multidrug resistance using polyalkyl cyanoacrylate (PACA) nanoparticles as "vectors".
As a developing concept, drug nanocarriers are expected to play a major role in delivering multiple drugs to tumor tissues by overcoming semi-permeable membranes and biological barriers such as the blood–brain barrier.
References
See also
Vector (molecular biology)
Cancer treatment
Nanomedicine
Nanobiotechnology
Paul Ehrlich#Magic bullet
Gold nanobeacons
Pharmacology
Nanomedicine | Drug vectorization | [
"Chemistry",
"Materials_science"
] | 177 | [
"Nanomedicine",
"Pharmacology",
"Nanotechnology",
"Medicinal chemistry"
] |
49,250,015 | https://en.wikipedia.org/wiki/Software%20durability | In software engineering, software durability means the solution ability of serviceability of software and to meet user's needs for a relatively long time. Software durability is important for user's satisfaction. For a software security to be durable, it must allow an organization to adjust the software to business needs that are constantly evolving, often in impulsive ways.
Durability of software depends on four characteristics mainly; i.e. software trustworthiness, Human Trust for Serviceability, software dependability and software usability.
References
software engineering | Software durability | [
"Technology",
"Engineering"
] | 112 | [
"Systems engineering",
"Computer engineering",
"Software engineering",
"Information technology",
"Computing stubs"
] |
49,250,082 | https://en.wikipedia.org/wiki/Christine%20Ortiz | Christine Ortiz is the dean of graduate education at the Massachusetts Institute of Technology (MIT), and Morris Cohen Professor of Materials Science and Engineering.
The goal of Ortiz's research program is a mechanistic-based understanding of tissue function, quality, and pathology. She is planning to create a new university, centered on project-based learning.
Education
BS, Rensselaer Polytechnic Institute, 1992
PhD, Cornell University, 1997
References
Living people
MIT School of Engineering faculty
Year of birth missing (living people)
Women materials scientists and engineers
Cornell University alumni
Rensselaer Polytechnic Institute alumni
Recipients of the Presidential Early Career Award for Scientists and Engineers | Christine Ortiz | [
"Materials_science",
"Technology"
] | 128 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
49,250,163 | https://en.wikipedia.org/wiki/Virtium | Virtium Solid State Storage and Memory (formerly known as Virtium Technology) is a privately held American company that manufactures semiconductor memory and solid-state disk (SSD) products for data storage in industrial/machine-to-machine designs, embedded systems, including small-footprint designs, and Industrial Internet of Things (IIoT) applications. The company's primary markets of focus include defense, industrial systems, network communications, and transportation. The name Virtium is derived from the word virtue.
Description
Virtium was co-founded in 1997 by Phu Hoang, a refugee from Vietnam, and Chinh Nguyen. Hoang lived on a boat before immigrating to North America and learned English in a refugee camp. Since co-founding Virtium, Hoang has been acknowledged for his entrepreneurship and innovation.
Headquartered in Rancho Santa Margarita, California, USA, and with operations elsewhere in North America, Europe and Asia, Virtium designs, builds and supports its products in the United States. Virtium's primary products are memory modules and solid-state drives that use flash storage and are designed primarily with the SATA and PCI Express interfaces.
Virtium was among the first to apply proprietary programming sequences that “bridge” between single-level-cell (SLC) and multi-level-cell (MLC) types of flash memory used in SSDs, thus drawing on the reliability of the former and the cost efficiencies of the latter. In 2016, Virtium introduced self-encrypting SSDs—the first family of industrial-grade SSDs with Advanced Encryption Standard (AES-256) self-encryption available across all major drive form factors and designed for data security and data integrity. Those self-encrypting SSDs placed first in the Board, Modules & Embedded Systems category of the ECN magazine 2017 Impact Awards. Also in 2016, Virtium became one of the first industry vendors to market eUSB 3.0 storage modules in the ultra-small, 10-pin form factor. Later the same year, Virtium doubled the top capacity of its very-low-profile (VLP) RDIMM and Mini-RDIMM DDR4 memory modules to 64GB—at the time the highest capacity for industrial-embedded memory modules. In early 2021, Virtium introduced three 32GB ultra-low-profile (ULP) DDR4 modules that represent the industry's first of that capacity in Mini-UDIMM, Mini-RDIMM and SO-UDIMM form factors, as well as the industry's first 64GB ULP RDIMM module.
In September 2017, Virtium debuted its StorFly M.2 NVMe SSDs that supported industrial temperatures, or I-Temp (−40 °C to +85 °C), and drew an industry-low 3 W of power. In 2019, the company expanded its StorFly family of SSDs to include industrial 3D NAND-based drives, followed by the StorFly-XR (XR is an initialism for "Extra Rugged") line of highly ruggedized SSDs using 3D NAND flash and XR-DIMM memory modules designed for military and aerospace applications. Virtium expanded the StorFly family further in 2019 with the addition of a four-terabyte SSD with industrial-temperature support and integrated data protection. In February 2020, the company brought to market its free StorKit SSD software suite for SSD qualification, migration from SLC and MLC to higher-density flash, and monitoring and maintenance of drives deployed locally or remotely. Also in 2020, Virtium announced an expansion to the StorFly SSD family through the addition of higher-capacity 2.5-inch SATA, M.2 SATA and M.2 NVMe drives with I-Temp support. To address the increasing role of industrial-grade storage in edge computing, Virtium collaborated with SolidRun later in 2020 to prequalify select Virtium SSDs, memory and SSD software for SolidRun computer-on-module and network computing platforms targeted at 5G communications systems. In early 2021, Virtium further expanded its SSD family with the Series 6 line of NVMe, I-Temp-supported drives focused on data-intensive workloads which was among Electronic Design magazine's Embedded Products and Solutions of the Week. Storage-industry journalist and author Tom Coughlin illustrated the need for durable solid-state storage for industrial-embedded applications in a 2021 Forbes article, which featured Virtium, its SSDs and the drives' applications. In May 2021, Virtium debuted the StorFly CFexpress PCIe Gen 4 Removable NVMe SSDs, the industry's first solid-state drives to incorporate NVMe, the PCI Express 4.0 interface and I-Temp in the highly compact CFexpress form factor.
In August 2015, Virtium secured investment from L Squared Capital Partners and added David Bradford and Tim Leyden to its board of directors. Court Square Capital Partners acquired L Squared Capital's investment in Virtium in May 2019.
Products and specialization
Virtium specializes in memory modules, advanced components, flash-based solid-state drives (for local and remote storage), and supporting software. Those product lines were expanded in 2015 with multiple additions to the company's industrial-embedded systems category.
The company's memory and storage products employ a variety of form factors and interfaces, including DIMM memory modules for DDR3L, MiniDIMM and ECC SoDIMM memory modules for DDR3L, and M.2, mSATA, CFast, Slim SATA, CompactFlash, PCI Express Mini Card, and eUSB SLC SSDs.
Competitors include SMART Modular Technologies and Swissbit.
References
External links
Official website
TEDx video of Virtium founder Phu Hoang
Virtium at-a-glance video
Companies established in 1997
Companies based in Orange County, California
Computer companies of the United States
Computer hardware companies
Computer memory companies | Virtium | [
"Technology"
] | 1,265 | [
"Computer hardware companies",
"Computers"
] |
49,250,287 | https://en.wikipedia.org/wiki/Sarcodon%20cyrneus | Sarcodon cyrneus is a species of tooth fungus in the family Bankeraceae. Found in Europe, it was described as new to science in 1975 by Dutch mycologist Rudolph Arnold Maas Geesteranus. The specific epithet cyrneus is derived from the Latin "Corsican", referring to Corsica, the type locality. Fruit bodies contains neurotrophic cyathane diterpene compounds called cyrneines.
References
External links
Images and description in Italian
Fungi described in 1975
Fungi of Europe
cyrneus
Fungus species | Sarcodon cyrneus | [
"Biology"
] | 110 | [
"Fungi",
"Fungus species"
] |
49,250,366 | https://en.wikipedia.org/wiki/Glucosone | Glucosone is a reactive carbonyl compound that can be produced by an Amadori rearrangement of a derivative of glucose. It is a dicarbonyl intermediate of the Maillard reaction whose production is higher under oxidative versus non-oxidative conditions.
References
Glucose | Glucosone | [
"Chemistry"
] | 60 | [
"Organic compounds",
"Organic compound stubs",
"Organic chemistry stubs"
] |
49,250,446 | https://en.wikipedia.org/wiki/Reactive%20carbonyl%20species | Reactive carbonyl species (RCS) are molecules with highly reactive carbonyl groups, and often known for their damaging effects on proteins, nucleic acids, and lipids. They are often generated as metabolic products. Important RCSs include 3-deoxyglucosone, glyoxal, and methylglyoxal. RCSs react with amines and thiol groups leading to advanced glycation endproducts (AGEs). AGE's are indicators of diabetes.
Reactive aldehyde species (RASP), such as malondialdehyde and 4-hydroxynonenal, are a subset of RCS that are implicated in a variety of human diseases.
See also
Reactive oxygen species
Reactive sulfur species
Reactive nitrogen species
References
Molecules
Carbon compounds | Reactive carbonyl species | [
"Physics",
"Chemistry",
"Biology"
] | 159 | [
"Molecular physics",
"Molecules",
"Biotechnology stubs",
"Biochemistry stubs",
"Physical objects",
"nan",
"Biochemistry",
"Atoms",
"Matter"
] |
49,250,487 | https://en.wikipedia.org/wiki/Reactive%20sulfur%20species | Reactive sulfur species (RSS) are a family of sulfur-based chemical compounds that can oxidize and inhibit thiol-proteins and enzymes. They are often formed by the oxidation of thiols and disulfides into higher oxidation states. Examples of RSS include persulfides, polysulfides and thiosulfate.
See also
Reactive oxygen species
Reactive nitrogen species
Reactive carbonyl species
References
Molecules
Sulfur compounds | Reactive sulfur species | [
"Physics",
"Chemistry"
] | 89 | [
"Molecular physics",
"Molecules",
"Physical objects",
"nan",
"Atoms",
"Matter"
] |
49,250,517 | https://en.wikipedia.org/wiki/Reductive%20stress | Reductive stress (RS) is defined as an abnormal accumulation of reducing equivalents despite being in the presence of intact oxidation and reduction systems. A redox reaction involves the transfer of electrons from reducing agents (reductants) to oxidizing agents (oxidants) and redox couples are accountable for the majority of the cellular electron flow. RS is a state where there are more reducing equivalents compared to reductive oxygen species (ROS) in the form of known biological redox couples such as GSH/GSSG, NADP+/NADPH, and NAD+/NADH. Reductive stress is the counterpart to oxidative stress, where electron acceptors are expected to be mostly reduced. Reductive stress is likely derived from intrinsic signals that allow for the cellular defense against pro-oxidative conditions. There is a feedback regulation balance between reductive and oxidative stress where chronic RS induce oxidative species (OS), resulting in an increase in production of RS, again.
Implications of reductive stress
There are several implications of an excess of reducing equivalents: regulation of cellular signaling pathways by decreasing cell growth responses, modification of transcriptional activity, perturbs disulfide bond formation within proteins, increase of mitochondrial malfunction, decrease in cellular metabolism, and cytotoxicity. The over expression of antioxidant enzymatic systems promote the excess production of reducing equivalents resulting in the depletion of ROS and prompting RS in cells. Nuclear factor erythroid 2–related factor 2 (Nrf2) is an important transcription factor that regulates a multitude of genes that code for antioxidant response and after uncontrolled amplification of this signaling pathway RS increases. Although different organelles may each have a different redox status, through probing for factors such as glutathione and hydrogen peroxide (H2O2), it was determined that reductive stress is present in the endoplasmic reticulum (ER) of senescent cells. Reductive stress is significant in the aging process of a cell and when ER oxidation status is elevated, cellular aging is slowed. In particular, when reductive stress is increased, it may result in many downstream effects such as increased apoptosis, decreased cell survival, and mitochondrial dysfunction—all of which need to be properly regulated to ensure that the needs of the cell are met. Data shows, in an isolated mitochondria, when there is a high ratio of NADH/NAD+, an example of RS, ROS increases significantly in the mitochondrial matrix which results in H2O2 spillover from the mitochondria. Reductive stress has even been suggested to lead to higher probability of cardiomyopathy in humans. This has also been mysteriously linked to the abundant presence of heat shock protein 27 (Hsp27), suggesting that high levels of Hsp27 induce can induce cardiomyopathy. Reductive stress is present in many diseases with abnormalities such as the increase of reducing equivalents, resulting in issues such as hypoxia-induced oxidative stress. A more reductive redox environment promotes cancer metastasis and cancer cells use reductive stress to promote growth and resist anti-cancer agents, such as chemotherapy and radiotherapy.
See also
Antioxidative stress
References
Biochemistry | Reductive stress | [
"Chemistry",
"Biology"
] | 699 | [
"Biochemistry",
"nan"
] |
49,250,544 | https://en.wikipedia.org/wiki/Succinylacetone | Succinylacetone is a chemical compound that is formed by the oxidation of glycine and is a precursor of methylglyoxal.
It is a pathognomonic compound found in the urine of patients with tyrosinemia type 1, which is due to congenital deficiency of an enzyme, fumarylacetoacetate hydrolase. This enzyme is involved in the catabolism of tyrosine, and if deficient, leads to accumulation of fumarylacetoacetate which is subsequently converted to succinylacetone which can be detected in the urine by GCMS. Succinylacetone also inhibits ALA dehydratase (PBG synthase) which increases ALA and precipitates acute neuropathic symptoms, similar to porphyria.
References
Diketones
Carboxylic acids | Succinylacetone | [
"Chemistry"
] | 176 | [
"Carboxylic acids",
"Functional groups"
] |
49,250,685 | https://en.wikipedia.org/wiki/Dienyl%20radical | Dienyl radicals are free radicals that can be formed by the oxidation of polyunsaturated fatty acids. These can combine with oxygen to form cis-trans lipid peroxyl radicals.
Benzene can be oxidized using a photocatalyst, QuCN+ to produce benzene radical cation. This benzene radical cation can produce a dienyl radical through nucleophilic reagent.
References
Medicinal chemistry | Dienyl radical | [
"Chemistry",
"Biology"
] | 94 | [
"Medicinal chemistry stubs",
"Biochemistry stubs",
"nan",
"Medicinal chemistry",
"Biochemistry"
] |
49,251,170 | https://en.wikipedia.org/wiki/Sarcodon%20leucopus | Sarcodon leucopus is a species of tooth fungus in the family Bankeraceae. Found in Asia and Europe, it was described as new to science in 1825 by Christian Hendrik Persoon. Mycologists Rudolph Arnold Maas Geesteranus and John Axel Nannfeldt transferred it to the genus Sarcodon in 1969. Fruit bodies of the fungus have flattened to slightly depressed caps up to in diameter. The surface texture, initially finely felt-like, later cracks to form shiny scales. Its color is pale purplish-brown to dark brown. The stipe measures long by thick. Spines on the cap underside are up to 15 mm long and about 1 mm thick. The flesh has a disagreeable odor, and a bitter taste. Spores are roughly spherical, typically measuring 7.2–7.9 by 4.5–5.6 μm. The fungus is considered endangered in Switzerland.
Fruit bodies of Sarcodon leucopus contain novel compounds called sarcoviolins that have been shown to have antioxidative and α-glucosidase inhibitory activity.
References
External links
Fungi described in 1825
Fungi of Asia
Fungi of Europe
leucopus
Taxa named by Christiaan Hendrik Persoon
Fungus species | Sarcodon leucopus | [
"Biology"
] | 256 | [
"Fungi",
"Fungus species"
] |
49,252,268 | https://en.wikipedia.org/wiki/Fluorothymidine%20F-18 | Fluorothymidine F-18 (FLT) is a tumor-specific PET tracer and radiopharmaceutical. It is an isotopologue of alovudine. FLT is suitable for monitoring how tumors respond to cytostatic therapy. FLT accumulates in proliferating cells where it indicates the activity of the enzyme thymidine kinase. Cell division can be characterized by the activity of that enzyme. FLT is phosphorylated as though it were thymidine, and is subsequently incorporated into DNA. Thymidine is essential for DNA replication. Considering that FLT lacks a 3′-hydroxy group, transcription of DNA is impeded following incorporating of FLT. FLT indicates changes in tumor cell proliferation by tracking the restoration of nucleosides from degenerated DNA.
References
PET radiotracers
Pyrimidinediones
Organofluorides | Fluorothymidine F-18 | [
"Chemistry"
] | 190 | [
"Chemicals in medicine",
"Medicinal radiochemistry",
"PET radiotracers"
] |
49,252,335 | https://en.wikipedia.org/wiki/Cryomyces%20antarcticus | Cryomyces antarcticus is a fungus of uncertain placement in the class Dothideomycetes, division Ascomycota. Found in Antarctica, it was described as new to science in 2005. It has been found to be able to survive the harsh outer space environment and cosmic radiation. A proposed mechanistic contributor to the unique resilience observed in C. antarcticus is the presence of its thick and highly melanized cell walls. This melanin may act to protect DNA from damage while C. antarcticus is exposed to conditions that are unsuitable for typical DNA repair systems to function.
References
External links
Enigmatic Dothideomycetes taxa
Fungi described in 2005
Fungi of Antarctica
Fungus species | Cryomyces antarcticus | [
"Astronomy",
"Biology"
] | 144 | [
"Fungi",
"Fungus species",
"Astronomy stubs",
"Astrobiology stubs"
] |
49,252,625 | https://en.wikipedia.org/wiki/ONOS | fa:کاربر:CSF-404/ONOS
The ONOS (Open Network Operating System) project is an open source community hosted by The Linux Foundation. The goal of the project is to create a software-defined networking (SDN) operating system for communications service providers that is designed for scalability, high performance and high availability.
History
On December 5, 2014, the Open Networking Lab (ON.Lab) along with other industry partners including AT&T and NTT Communications released the ONOS source code to start the open source community. On October 14, 2015, the Linux Foundation announced that ONOS had joined the organization as one of its collaborative projects.
The project was started around October 2012 under the leadership of Pankaj Berde, an architect at ON.Lab. The name ONOS was coined around end of 2012 by Berde. Early prototype was shown in April 2013 at Open Networking Summit (ONS) and journey of initial iterations featured at ONS 2014.
Technology overview
The software is written in Java and provides a distributed SDN applications platform atop Apache Karaf OSGi container. The system is designed to operate as a cluster of nodes that are identical in terms of their software stack and can withstand failure of individual nodes without causing disruptions in its ability to control the network operation.
While ONOS leans heavily on standard protocols and models, e.g. OpenFlow, NETCONF, OpenConfig, its system architecture is not directly tied to them. Instead, ONOS provides its own set of high-level abstractions and models, which it exposes to the application programmers. These models can be extended by the applications at run-time. To prevent the system from becoming tied to a specific configuration or control protocol, any software in direct contact with protocol-specific libraries and engaging in direct interactions with network environment is deliberately isolated into its own tier referred to as a provider or a driver. Likewise, any software in direct contact with intra-cluster communication protocols is deliberately isolated into its own tier referred to as a store.
The platform provides applications with a number of high-level abstractions, through which the applications can learn about the state of the network and through which they can control the flow of traffic through the network. The network graph abstraction provides information about the structure and topology of the network. The flow objective is a device-centric abstraction that allows applications to direct flow of traffic through a specific device without the need to be aware of the device table pipeline. Similarly, the intent is a network-centric abstraction that gives application programmers the ability to control network by specifying what they wish to accomplish rather than specifying how they want to accomplish it. This simplifies application development and at the same time provides the platform with added degrees of freedom to resolve what would normally be considered conflicting requests.
Applications (core extensions) can be loaded and unloaded dynamically, via REST API or GUI, and without the need to restart the cluster or its individual nodes. ONOS application management subsystem assumes the responsibility for distributing the application artifacts throughout the cluster to assure that all nodes are running the same application software. ONOS base distribution contains over 175 applications, which fall into numerous categories, e.g. traffic steering apps, device drivers, ready-to-use YANG models, utilities, monitoring apps.
The system provides REST API, CLI and an extensible, dynamic web-based GUI. gRPC interfaces for ONOS are under active development.
Use cases
The ONOS software has been used as a platform that applications have been written on top of or has been integrated into other projects. A number of use cases demonstrate how the software is being used today—including global research networking deployments, multilayer network control, and central office re-designed as a datacenter.
Releases
The following lists the different ONOS releases that are all named after different types of birds in alphabetical order:
Members
There are two tiers of membership for ONOS: Partner and Collaborator, with varying levels of commitment.
Partners
AT&T
China Unicom
Ciena
Cisco
Comcast
Deutsche Telekom
Ericsson
Fujitsu
Google
Huawei
Intel
NEC
Nokia
NTT Communications
Radisys
Samsung Electronics
Türk Telekom
Verizon
Collaborators
AARNet
ADARA Networks
Airhop Communications
Akamai
AmLight
BlackDuck
BTI Systems
Beijing University of Posts and Telecommunications
Cavium
ClearPath Networks
CNIT
CREATE-NET
Criterion Networks
CSIRO
ECI Telecom
ETRI
Consortium GARR
GEANT
Happiest Minds
Internet2
INSPIRE group
KAIST
KREONET
KISTI
NAIM Networks
NetCracker
OpenFlow Korea
OPLink Communications
Open Networking Foundation
Postech
SRI International
National Chiao-Tung University
See also
List of SDN controller software
References
External links
Computer networking
Linux Foundation projects | ONOS | [
"Technology",
"Engineering"
] | 972 | [
"Computer networking",
"Computer science",
"Computer engineering"
] |
49,253,056 | https://en.wikipedia.org/wiki/Global%20Technopreneurship%20Challenge | The Global Technopreneurship Challenge is an international competition organised by The Technopreneurship Institute through which global challenges are addressed, including the 14 Grand Challenges for Engineering for the 21st century and The Global Goals. Participants address the selected challenges through technology and entrepreneurship. Each year, cities from all over the world bid to host the year's Global Technopreneurship Challenge.
About the Challenge
The Global Technopreneurship Challenge is run in two stages, the preliminary stage and the finals. The preliminary stage is carried out online via a massive open online course on Open Learning where participants form teams and participate in online classes and activities. During this stage the participants acquire the knowledge necessary to conceive, design, implement and operate solutions that are technologically feasible, economically viable, desirable and environmentally sustainable. The teams with the best solutions will then be invited to the finals where they will be given a chance to pitch to academics, and industrial experts as well as investors.
The first challenge was held in Kuwait in 2015.
Global Technopreneurship Challenges
Kuwait Global Technopreneurship Challenge 2015
The Kuwait Global Technopreneurship Challenge 2015 was held from July to November. It was organised by Kuwait University in collaboration with Taylor's School of Engineering and The Technopreneurship Institute.
The Kuwait Global Technopreneurship Challenge aimed to address three of the 14 grand challenges, making solar energy economical, advance personalise learning and advance health informatics. The preliminary stage of the competition was held from July to September 2015 a total of 65 teams from 151 countries worked on providing solutions to address these grand challenges. 17 teams of finalist were chosen by a panel of international judges to attend the finals in Kuwait. The finals were held from the 14th to 16 November in conjunction with the 40th anniversary of the College of Petroleum and Engineering, Kuwait University.
The winners of the challenge were: Champion: Legacy, 1st Runner Up: E-Innovation, 2nd Runner Up: Diabetes Lifecycle Management System, and Judges Choice: The Concept Crew.
Partners and Sponsors
Innovation partner - General Electric
Sponsors - KFAS, Zain, The National Fund, Boubyan Bank, BP
Supported by - Global Engineering Deans Council , Global Challenges Alliance , Asia School of Business, Open Learning.
Winners
References
External links
The Technopreneurship Institute
xGTC
Kuwait Global Technopreneurship Challenge
GE investing in young engineers
Technopreneurship Challenge winners work to reduce car accidents in Kuwait
Entrepreneurs tackle local issues at Kuwait Global Technopreneurship Challenge
Engineering competitions
Business plan competitions | Global Technopreneurship Challenge | [
"Technology"
] | 521 | [
"Science and technology awards",
"Engineering competitions"
] |
49,253,092 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20208 | Zinc finger protein 208 is a protein that in humans is encoded by the ZNF208 gene.
Function
Zinc finger proteins (ZNFs), such as ZNF208, bind DNA and, through this binding, regulate gene transcription. Most ZNFs contain conserved C2H2 motifs and are classified as Kruppel-type zinc fingers. A conserved protein motif, termed the Kruppel-associated box (KRAB) domain, mediates protein-protein interactions (Eichler et al., 1998 [PubMed 9724325]). See ZNF91 (MIM 603971) for further information on ZNFs.
References
Further reading
Proteins | Zinc finger protein 208 | [
"Chemistry"
] | 146 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,253,125 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20226 | Zinc finger protein 226 is a protein that in humans is encoded by the ZNF226 gene.
Gene
The zinc finger protein 226 is also known as the Kruppel-associated box protein. Within humans, the ZNF226 gene is found on the plus strand of chromosome19q13, spanning 13,311 nucleotides from 44,165,070 to 44,178,381.
Transcript
Currently, there are 20 different transcript variants encoding ZNF226. All of them have six or seven identified exon regions within ZNF226. The longest identified transcript, ZNF226 transcript variant x4 spans 2,797 base pairs (bp).
Protein
ZNF226 is currently known to have three isoforms within humans: ZNF226 isoform X1, ZNF226 isoform X2, and ZNF226 isoform X3. The ZNF226 isoform X1 protein is the longest known variant, with 803 amino acids. This protein contains the Kruppel associated box A (KRAB-A) domain, which functions as a transcriptional repressor. However, the exact function of the ZNF226 protein is currently unknown. Within isoform X1, there are 18 C2H2 zinc finger structural motif (zf-C2H2) domains, which are known to bind either zinc ions (Zn2+) or nucleic acid (Figure 7–8). Within those regions, cysteine and histidine are the primary amino acids that bind to Zn2+ or nucleic acid, although other amino acids have been identified for binding (Figure 7–8). In addition to the KRAB-A domain and zf-C2H2 domains, there are zinc finger double domains which also contain binding sites for ions or nucleic acids.
ZNF226 human and ortholog protein sequences have molecular weights between 89 and 92 kDa. They had isoelectric points (pI) ranging from 8.60 to 9.00. In humans, the zf-C2H2 and zinc finger double domain region of ZNF226 isoform X1 is 59.3 kDa with a theoretical pI of 9.11. With the spacing of cysteine, or C, there is a cysteine every three amino acids. At least one of the amino acids in between the C's are either aspartic acid or glutamic acid. Despite the region's patterns of aspartic acid, it is still considered to have a lesser amount of the amino acid at 1.9%. There is also repetition within the chemical patterns within humans that is characteristic of ZNF226. These repetitions appear most common within the zf-C2H2 and zinc finger double domains of the protein, notably with cysteine and histidine binding sites. Predicted secondary structures of ZNF226 demonstrate a variable number of alpha helices, beta-stranded bridges, and random coils throughout the protein. Using various programs, such as GOR4 and the Chou and Fasman program, there is overall similarity in the predictions of coiled, stranded, and helix regions throughout the protein.
Regulation
Gene
Promoter
Using the Genomatix software, GXP_7536741 (1142 bp) was identified as the best promoter of ZNF226 (Figure 1). Within the last 500 bp of the promoter, the signal transducer and activator of transcription (V$STAT.01), selenocysteine tRNA activating factor (V$THAP11.01), and cell cycle regulators: cell cycle homology region (V$CHR.01) were conserved among Homo sapiens, Macaca mulatta, Pan troglodytes, and Canis lupus familiaris. In addition, the SPI-1 proto-oncogene; hematopoietic TF PU.1 (V$SPI1.02) was also known for binding to a promoter region within the c-fes proto-oncogene which encodes tyrosine kinase. The TF binding site is also found in two regions within the promoter sequence. The signal transducer and activator of transcription binding site was also conserved in two regions, and is known to have a higher binding specificity. The selenocysteine tRNA activating factor plays a role in embryonic stem cell regeneration. The cell cycle regulators: cell cycle homology region binding site plays an important role in cell survival, where mutations in the transcription factor can lead to apoptosis.
Tissue distribution
In terms of gene expression, ZNF226 is generally expressed in most tissues. Microarray data illustrates higher expression of ZNF226 within the ovaries. This is further supported by data which depicts a decrease in ZNF226 expression in granulosa cells within individuals with polycystic ovary syndrome. There was also higher expressions of ZNF226 observed within the thyroid compared to other tissues. Evidence of decreased ZNF226 expression is observed with individuals with papillary thyroid cancer.
Within fetuses, there is some level of ZNF226 expression present within all tissues throughout the gestational period of 10 to 20 weeks. However, there is a higher level of ZNF226 expression in the heart at 10 weeks of gestation, and a decreased level of expression within kidneys at 20 weeks gestation.
ZNF226 expression has been observed within epithelial progenitor cells (EPCs) in the peripheral blood (PB) and umbilical cord blood (CB). The gene expression is lower in PB-EPCs when compared to CB-EPCs. PB-EPCs have more tumor suppressor (TP53) expression when compared to CB-EPCs. CB-EPCs have more angiogenic expression, or growth and splitting of vasculature.
Transcript
Using RNAfold, minimum free energy structures were created based on the extended 5’ and 3’ untranslated region (UTR) in human sequences. Unconserved amino acids, miRNA, stem-loop formations, and RNA binding proteins (RBPs) are shown on the diagram (Figure 2–3).
miRNA targeting
Within the 5’ UTR region, both miR-4700-5p and miR-4667-5p were referenced in an experiment which identified certain miRNAs expressed consistently in ERBB2+ breast cancer gene. In addition, miR-8089 was referenced in a study showing certain novel miRNAs found within sepsis patients. miR-4271 was shown to have effects on coronary heart disease binding to the 3' UTR region of the APOC3 gene. Literature on miR-7113-5p shows that this miRNA is a mirtron.
Within the 3’ UTR region, miR-3143 is referenced in a study where miRNAs were expressed consistently in ERBB2+ breast cancer gene. miR-152-5p plays a role in inhibiting DNA methylation of genes involved in metabolic and inflammatory pathways. miR-31-3p is overexpressed in esophageal squamous cell carcinoma (ESCC). One miRNA result, miR-150-5p, was conserved across multiple homologs within the 3’ UTR region more than 3000 bp downstream. The miR-150-5p miRNA plays a role in colorectal cancer (CRC), where a lower expression of the miRNA was associated with a suppression of CRC metastasis.
RNA binding proteins
In terms of some of the RBPs found, PAPBC1 had five binding sites, two of which are highlighted on the 5’ UTR. This protein is known to attach poly-a-tails for proteins that have entered the cytoplasm, preventing them from re-entry into the nucleus. The FUS protein was another one found with a binding site on a predicted stem loop. The gene encodes for a protein which facilitates transportation of the protein into the cytoplasm. Within the 3’ UTR, the RBMY1A1, RBMX, and ACO1 proteins were some of the top scoring RBPs. The RBMY1A1 is a protein known to partake in splicing, and is required for sperm development. The RBMX protein is a homolog of the RBMY protein involved in sperm production. It is also known to promote transcription of a tumor suppressor gene, TXNIP. ACO1 is another RBP known to bind with mRNA to regulate iron levels. By binding to iron responsive elements, it can repress translation of ferritin and inhibit degradation of transferring receptor mRNA when iron levels become low.
Protein
Analysis to predict post-translational modifications of the protein were conducted on. Based on the results of Expasy's Myristoylator in Homo sapiens, Mirounga leonina, and Fukomys damarensis, it can be concluded that ZNF226 is not myristoylated at the N-terminus. Numerous predicted binding sites for post-translational modifications were also identified among the three species. The phosphorylation region at the C-terminus of the protein was also identified as a match for the protein kinase C phosphorylation binding site. S-nitrosylation was another identified modification at C354 (Figure 2). This modification is found in SRG1, a zinc finger protein that plays a role preventing nitric oxide (NO) synthesis. When NO is sustained, s-nitrosylation occurs within the protein, disrupting its transcriptional repression abilities. Acetylation was another modification identified. In the case of promyelocytic leukemia, a condition resulting in the abundance of blood forming cells in the bone marrow, promyelocytic leukemia zinc finger proteins are known to be activated by histone acetyltransferases, or by acetylation of a C-terminus lysine. Acetylation in other zinc finger proteins, such as GATA1, are known to enhance their ability to interact with other proteins. Arginine dimethylation is another identified modification within ZNF226. Arginine methylation of cellular nucleic acid binding protein (CNBP), a zinc finger protein, has shown to impede its ability to bind nucleic acids.
It is predicted that ZNF226 localizes within the nucleus, which aligns with its known functions as a transcription factor. It has also been predicted to localize within the mitochondria.
Homology/evolution
Although there is little information available on the ZNF226 gene, homologs of the gene have been found across eukaryotes and bacteria species. Strict orthologs were only found within mammals (Figure 4). The ZNF226 gene is also closely related to the paralog ZNF234 in humans, and the Zfp111 gene within mice. Across the various species in which ZNF226 orthologs and homologs that were identified, conservation of the C2H2 binding sites is apparent (Figure 4–5). In human ZNF226 paralogs, there is also conservation of the C2H2 binding sites, as well as nucleic acid binding sites.
Slow rate evolution is apparent for the ZNF226 protein. It evolves in a manner similar to the cytochrome c protein instead of the fibrinogen alpha chain protein (Figure 6).
Interacting Proteins
Two interactions detected via the two hybrid method occurred with SSBP3 and ATF4, both of which are transcription factors.
ATF4/CREB-2 is a transcription factor which binds to the long terminal repeat of the human T-cell leukemia type1 virus (HTLV-1). It can be an activator of HTLV-1.
SSBP3/CSDP is found in mice embryonic stem cells to develop into trophoblasts (provide nutrients to embryo). ZNF226 is expressed at greater levels within human stem cells.
Function
With ZNF226 being a transcription factor, playing a role in transcriptional repression, the 18 zf-C2H2 binding domains are predicted to bind to the DNA sequence shown in the sequence logo (Figure 7–9).
Clinical significance
Associated diseases and conditions
A mutation within ZNF226 gene has been positively correlated with the presence of hepatocellular carcinoma (HCC). A particular SNP (rs2927438) also correlated with an increased expression of ZNF226 in brain frontal cortical tissue and peripheral mononuclear cells, such as T cells and B cells. The promoter region of ZNF226 was found to be hypomethylated in those who were exposed to the Chinese famine. The hypomethylated region in ZNF226 was shown to have a correlation of methylation in the blood and the prefrontal cortex, although the exact function of the protein in the famine is not understood. ZNF226 gene was listed among many other genes with a copy number variation (CNV) that was associated with single common variable immunodeficiency (CVID).
SNPs
Numerous SNPs were identified throughout the ZNF226 gene. Within the GXP_7536741 promoter, there were two SNPs of interest that were found. Listed below are associated transcription factors for both SNPs.
References
Proteins | Zinc finger protein 226 | [
"Chemistry"
] | 2,866 | [
"Proteins",
"Biomolecules by chemical classification",
"Molecular biology"
] |
49,253,142 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20112 | Zinc finger protein 112 is a protein that in humans is encoded by the ZNF112 gene.
References
Further reading
Proteins | Zinc finger protein 112 | [
"Chemistry"
] | 27 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,253,158 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20426 | Zinc finger protein 426 is a protein that in humans is encoded by the ZNF426 gene.
Function
Kaposi's sarcoma-associated herpesvirus (KSHV) can be reactivated from latency by the viral protein RTA. The protein encoded by this gene is a zinc finger transcriptional repressor that interacts with RTA to modulate RTA-mediated reactivation of KSHV. While the encoded protein can repress KSHV reactivation, RTA can induce degradation of this protein through the ubiquitin-proteasome pathway to overcome the repression. Several transcript variants encoding different isoforms have been found for this gene.
References
Further reading
Proteins | Zinc finger protein 426 | [
"Chemistry"
] | 146 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,253,170 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20576 | Zinc finger protein 576 is a protein that in humans is encoded by the ZNF576 gene.
References
Further reading
Proteins | Zinc finger protein 576 | [
"Chemistry"
] | 28 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,253,215 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20613 | Zinc finger protein 613 is a protein that in humans is encoded by the ZNF613 gene.
References
Further reading
Proteins | Zinc finger protein 613 | [
"Chemistry"
] | 28 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,253,220 | https://en.wikipedia.org/wiki/PomBase | PomBase is a model organism database that provides online access to the fission yeast Schizosaccharomyces pombe genome sequence and annotated features, together with a wide range of manually curated functional gene-specific data. The PomBase website was redeveloped in 2016 to provide users with a more fully integrated, better-performing service (described in ).
Data Curation and Quality Control
PomBase staff manually curate a wide variety of data types using both primary literature and bioinformatics sources, and numerous mechanisms are employed to ensure both syntactical and biological content validity.
Types of data curated include:
Genome sequence and features (e.g. physical location of genes in the genome)
Protein and ncRNA functions, the cellular processes they participate in and where they localize
Phenotypes associated with different alleles and genotypes
Specific protein modification sites and when they occur
Human and budding yeast orthologs of S. pombe genes (manually curated dataset)
Metadata of datasets loaded into the genome browser
Disease associations for when the human ortholog is known to cause disease
Data regarding when specific genes are expressed
Complementation data for where there is functional complementation between a fission yeast gene and a gene from another organism
Subunit composition of complexes
Data Organization
Gene annotation can be viewed either at a gene-specific level (on the gene pages) or at a term-specific level (on the ontology term pages). This makes it possible to either:
View all annotations created for a gene, for example pat1
View all genes annotated a term, for example cytokinesis
View all annotations created from a specific reference, for example 26776736 Chica et al. 2016
Genome-wide datasets (including protein datasets, all annotations, manually curated ortholog lists etc) can be accessed from the datasets page. Datasets suitable for display in a genome browser and that have been loaded can be accessed via the PomBase JBrowse instance.
PomBase uses several biological ontologies to capture gene-specific information, including:
Gene Ontology (GO) - used to describe the enzymatic functions, biological roles and cellular locations of gene products
Fission Yeast Phenotype Ontology (FYPO), Used to associate phenotypes with alleles of genes, in comparison to the phenotype of the reference strain
Sequence Ontology - used to describe DNA or protein features
Protein modifications - using PSI-MOD
Gene Characterization Status
The GO slim page provides an overview of the "biological role" of all "known" fission yeast genes - these are proteins that have either been experimentally characterized in fission yeast, or in another species and transferred by orthology.
Remarkably, nearly 20% of eukaryotic proteomes, from yeast to human, are uncharacterized in terms of the pathways and processes that these proteins participate in, making it one of the great unsolved problems in biology. The role that these proteins play in biology, have not yet been discovered in any species. To aid research into these unknown proteins, PomBase maintains an inventory of uncharacterized fission yeast proteins. The priority unstudied genes list represents the subset of uncharacterized fission yeast genes that are conserved to man, making it an especially high priority research target.
Community co-Curation
To supplement the work of the small team of professional PomBase curators, fission yeast researchers contribute annotations directly to PomBase via an innovative community curation scheme, for which an online curation tool, Canto, has been developed. Community curation is reviewed by PomBase staff, and this results in highly accurate, effectively co-curated, annotations.
PomBase maintains an annotation stats page.
Knowledgebase Updates
News updates on the PomBase homepage
Posts to the research community mailing list
NAR ([Nucleic Acids Research]) database updates
Tweets (@PomBase)
Facebook group
Linkedin group
Documentation
Pombase provides both documentation and an FAQ.
Usage of PomBase as a research tool is explored in the "Eukaryotic Genomic Databases" (Methods and Protocols) book chapter. Developments and updates are described in the NAR Database Issue papers.
For a detailed overview of using S. pombe as a model organism see the genetics primer
References
External links
PomBase
Genetics databases
Genetic engineering in the United Kingdom
Medical databases in the United Kingdom
Medical genetics
Model organism databases
Science and technology in Cambridgeshire
South Cambridgeshire District
Wellcome Trust | PomBase | [
"Biology"
] | 952 | [
"Model organism databases",
"Model organisms"
] |
49,253,469 | https://en.wikipedia.org/wiki/Holmium%E2%80%93magnesium%E2%80%93zinc%20quasicrystal | A holmium–magnesium–zinc (Ho–Mg–Zn) quasicrystal is a quasicrystal made of an alloy of the three metals holmium, magnesium and zinc that has the shape of a regular dodecahedron, a Platonic solid with 12 five-sided faces. Unlike the similar pyritohedron shape of some cubic-system crystals such as pyrite, this quasicrystal has faces that are true regular pentagons.
The crystal is part of the R–Mg–Zn family of crystals, where R=Y, Gd, Tb, Dy, Ho or Er. They were first discovered in 1994. These form quasicrystals in the stoichiometry around . Magnetically, they form a spin glass at cryogenic temperatures.
While the experimental discovery of quasicrystals dates back to the 1980s, the relatively large, single grain nature of some Ho–Mg–Zn quasicrystals has made them a popular way to illustrate the concept.
See also
Complex metallic alloys
References
Quasicrystals
Tessellation
Magnesium alloys
Zinc alloys
Rare earth alloys
Holmium | Holmium–magnesium–zinc quasicrystal | [
"Physics",
"Chemistry",
"Materials_science",
"Mathematics"
] | 232 | [
"Materials science stubs",
"Rare earth alloys",
"Alloy stubs",
"Magnesium alloys",
"Tessellation",
"Euclidean plane geometry",
"Crystallography stubs",
"Crystallography",
"Alloys",
"Zinc alloys",
"Planes (geometry)",
"Quasicrystals",
"Symmetry"
] |
49,254,672 | https://en.wikipedia.org/wiki/Rhodium-platinum%20oxide | Rhodium-platinum oxide (Rh–Pt oxide), or Nishimura's catalyst, is an inorganic compound used as a hydrogenation catalyst.
Uses
Rh–Pt oxide is used to reduce various aromatic compounds to their respective cycloalkanes or saturated heterocycles under mild conditions (i.e. often at room temperature and atmospheric pressure). In this application, Rh–Pt oxide is superior to other group 10 catalysts such as platinum dioxide. Furthermore, the catalyst can be used to carry out the reaction with minimal losses of oxygen containing functional groups via hydrogenolysis.
Preparation
An aqueous solution of rhodium chloride, chloroplatinic acid, and sodium nitrate is evaporated and then fused in a porcelain dish between 460-480°C until the oxides of nitrogen cease (≈10 minutes). The resulting solidified mass is then washed with distilled water and dilute sodium nitrate followed by drying with calcium chloride to yield the catalyst. Typically the ratio of metals used for the catalyst is 3:1 Rh/Pt or 7:3 Rh/Pt.
See also
Rhodium-catalyzed hydrogenation
Rhodium(III) oxide
Wilkinson's catalyst
Platinum black
Platinum on carbon
Palladium on carbon
Birch reduction
References
Hydrogenation catalysts
Rhodium(III) compounds
Platinum(IV) compounds
Transition metal oxides | Rhodium-platinum oxide | [
"Chemistry"
] | 289 | [
"Hydrogenation catalysts",
"Hydrogenation"
] |
49,255,451 | https://en.wikipedia.org/wiki/Economics%20of%20plastics%20processing | The economics of plastics processing is determined by the type of process. Plastics can be processed with the following methods: machining, compression molding, transfer molding, injection molding, extrusion, rotational molding, blow molding, thermoforming, casting, forging, and foam molding. Processing methods are selected based on equipment cost, production rate, tooling cost, and build volume. High equipment and tooling cost methods are typically used for large production volumes whereas low - medium equipment cost and tooling cost methods are used for low production volumes. Compression molding, transfer molding, injection molding, forging, and foam molding have high equipment and tooling cost. Lower cost processes are machining, extruding, rotational molding, blow molding, thermoforming, and casting. A summary of each process and its cost is displayed in figure 1.
Aspects of plastic processing
Degradable plastics
Oxo-degradable plastics: these are petroleum-based plastics with additives such as transition metals and metals salts that promote the process of fragmentation of the plastic when exposed to a particular environment, such as high temperature or oxygen rich one, for a prolonged period of time. Fragmentation exposes a larger surface area of the plastic to colonies of bacteria that eventually decompose the polymer into its lower energy state components: carbon dioxide and water.
Some aspects to take into account regarding this method to dispose of end-of-life plastics are:
The type of polymer: experiments conducted by Chiellini et al. confirmed that bacteria are only able to decompose low molecular weight polymers (at least at a rate that can be appreciated).
Environmental conditions: the time for fragmentation/degradation varies according to conditions which aren’t always controllable.
Material’s potential to be recycled: this characteristic will be compromised, since the polymer’s durability or strength will be affected by the additives that accelerate fragmentation.
Classifying a polymer as bio-degradable requires specifications regarding these aspects.
Important economic aspects that need to be considered when disposing of degradable polymers include:
Waste landfill costs: if plastics represent a significant percentage of waste in a particular region, manufacturing plastics with bio-degradable properties may be more profitable and ecologically friendly than merely disposing of a non-degradable plastic. By using degradable polymers, costs due to waste transportation, landfill maintenance, new landfill excavation and environmental hazard control can be avoided.
Lost end-of-life plastic potential: processes such as energy recovery of the plastic by incineration or biological treatment and material recovery by recycling have to be taken into account when assessing the feasibility of manufacturing degradable polymers.
Reusable plastic containers
The implementation of reusable plastic containers arises as a consequence of concerns with sustainability and environmental impact. Use of recyclable plastic packages is beneficial environmentally but is more expensive. The adoption of reusable plastic containers will amount to an approximate annual increase of 0.058 euros/kg of delivered goods. The cost associated with reusable plastic containers are packaging purchasing costs, transportation costs, labor/handling costs, management costs, and costs resulting from losses. Packaging purchasing costs encompasses the cost of the containers as well as any associated service costs. This cost is reoccurring but is only relevant once every 50 cycles, which is the typical lifetime of reusable plastic containers. One cycle consists of the initial stages of processing plastic containers all the way to the use and recycling of these containers by the consumers. Transportation costs are slightly higher for reusable plastic containers as compared to traditional use and throwaway plastic containers in that these reusable containers need additional transportation to recycling facilities. Reusable plastic containers also require work loading and unloading from trucks as well as quality inspection, this adds additional labor costs. Management costs exists because reusable plastic container stock count needs to be managed. The final cost of reusable plastic containers is the cost incurred when packages are lost or there are errors within the management system. Figure 2 provides a detailed summary of the costs associated with adopting reusable plastic containers.
Incineration of plastics
Recycling plastics presents the difficulty of handling mixed plastics, as unmixed plastics are usually necessary to maintain desirable properties. Mixing many plastics results in diminished material properties, with even just a few percent of polypropylene mixed with polyethylene producing a plastic with significantly reduced tensile strength. An alternative to recycling of these plastics and those which can’t be easily recycled such as thermosets is to use degradation to break the polymers down into monomers of low molecular weight. The products of this process can be used to make high quality polymers however energy stored in the polymer bonds is lost during this process.
An alternative to economically dispose of plastics is to burn them in an incinerator. Incinerators capable of cleanly burning polymers exist and while they require significant capital investment, the energy produced offsets the economic impact. Since most plastics are produced from petroleum, their molecules consist exclusively or primarily of carbon, oxygen, and hydrogen atoms. With proper design, an incinerator can completely combust these plastics allowing the recovery of energy stored in the original petroleum feedstock which would otherwise escape during processes such as degradation. Some polymers contain chlorine or nitrogen which can result in undesirable combustion products however the use of scrubbers can remove such products. The end result is that many polymers burn more cleanly than coal and as clean as most oils.
References
Plastics
Recycling | Economics of plastics processing | [
"Physics"
] | 1,133 | [
"Amorphous solids",
"Unsolved problems in physics",
"Plastics"
] |
49,256,303 | https://en.wikipedia.org/wiki/EcoRI | EcoRI (pronounced "eco R one") is a restriction endonuclease enzyme isolated from species E. coli. It is a restriction enzyme that cleaves DNA double helices into fragments at specific sites, and is also a part of the restriction modification system. The Eco part of the enzyme's name originates from the species from which it was isolated - "E" denotes generic name which is "Escherichia" and "co" denotes species name, "coli" - while the R represents the particular strain, in this case RY13, and the I denotes that it was the first enzyme isolated from this strain.
In molecular biology it is used as a restriction enzyme. EcoRI creates 4 nucleotide sticky ends with 5' end overhangs of AATT. The nucleic acid recognition sequence where the enzyme cuts is G↓AATTC, which has a palindromic complementary sequence of CTTAA↓G. Other restriction enzymes, depending on their cut sites, can also leave 3' overhangs or blunt ends with no overhangs.
History
EcoRI is an example of type II restriction enzymes which now has more the 300 enzymes with more than 200 different sequence-specificities, which has transformed molecular biology and medicine.
EcoRI, discovered in 1970, was isolated by PhD student Robert Yoshimori who investigated clinical E. coli isolates that contained restriction systems presented on its plasmids. The purified isolates became known as EcoRI that is used to cleave G’AATTC.
Structure
Primary structure
EcoRI contains the PD..D/EXK motif within its active site like many restriction endonucleases.
Tertiary and quaternary structure
The enzyme is a homodimer of a 31 kilodalton subunit consisting of one globular domain of the α/β architecture. Each subunit contains a loop which sticks out from the globular domain and wraps around the DNA when bound.
EcoRI has been cocrystallized with the sequence it normally cuts. This crystal was used to solve the structure of the complex (). The solved crystal structure shows that the subunits of the enzyme homodimer interact with the DNA symmetrically. In the complex, two α-helices from each subunit come together to form a four-helix bundle. On the interacting helices are residues Glu144 and Arg145, which interact together, forming a crosstalk ring that is believed to allow the enzyme's two active sites to communicate.
Uses
Restriction enzymes are used in a wide variety of molecular genetics techniques including cloning, DNA screening and deleting sections of DNA in vitro. Restriction enzymes, like EcoRI, that generate sticky ends of DNA are often used to cut DNA prior to ligation, as sticky ends make the ligation reaction more efficient. One example of this use is in recombinant DNA production, when joining donor and vector DNA. EcoRI can exhibit non-site-specific cutting, known as star activity, depending on the conditions present in the reaction. Conditions that can induce star activity when using EcoRI include low salt concentration, high glycerol concentration, excessive amounts of enzyme present in the reaction, high pH and contamination with certain organic solvents.
See also
EcoRII, another nuclease enzyme from E. coli.
EcoRV, another nuclease enzyme from E. coli.
References
External links
EC 3.1.21
Bacterial enzymes
Restriction enzymes
Nucleases | EcoRI | [
"Biology"
] | 716 | [
"Genetics techniques",
"Restriction enzymes"
] |
49,256,492 | https://en.wikipedia.org/wiki/Zfp82%20zinc%20finger%20protein | ZFP82 zinc finger protein is a protein that in humans is encoded by the ZFP82 gene.
References
Further reading
Proteins | Zfp82 zinc finger protein | [
"Chemistry"
] | 29 | [
"Biomolecules by chemical classification",
"Proteins",
"Molecular biology"
] |
49,256,520 | https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20395 | Zinc finger protein 395 is a protein that in humans is encoded by the ZNF395 gene.
References
Further reading
Proteins | Zinc finger protein 395 | [
"Chemistry"
] | 27 | [
"Proteins",
"Biomolecules by chemical classification",
"Molecular biology"
] |
72,994,040 | https://en.wikipedia.org/wiki/Copper%28II%29%20telluride | Copper(II) telluride is an inorganic compound with the chemical formula CuTe that occurs in nature as a rare mineral vulcanite.
References
Copper(II) compounds
Tellurides | Copper(II) telluride | [
"Chemistry"
] | 38 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
72,994,041 | https://en.wikipedia.org/wiki/Copper%28I%29%20telluride | Copper(I) telluride is an inorganic compound with the chemical formula Cu2Te. It can be synthesized by reacting elemental copper and tellurium with a molar ratio of 2:1 at 1200 °C in a vacuum. Cu2Te has potential applications in thermoelectric elements and in solar cells, where it is alloyed with cadmium telluride to create a heterojunction.
References
Copper(I) compounds
Tellurides | Copper(I) telluride | [
"Chemistry"
] | 95 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
72,994,042 | https://en.wikipedia.org/wiki/Copper%20ditelluride | Copper ditelluride is an inorganic compound with the chemical formula CuTe2. It is a superconductor with a C18 structure and a transition temperature of 1.3 K. CuTe2 crystals can be synthesized by reacting elemental copper and tellurium with a molar ratio of 1:2 at a pressure of 65 kbar for 1–3 hours at 1000–1200 °C, followed by slow cooling.
References
Copper(II) compounds
Tellurides
Transition metal dichalcogenides | Copper ditelluride | [
"Chemistry"
] | 102 | [
"Inorganic compounds",
"Inorganic compound stubs"
] |
72,994,520 | https://en.wikipedia.org/wiki/Somatostatin%20receptor%20antagonist | Somatostatin receptor antagonists (or somatostatin inhibitors) are a class of chemical compounds that work by imitating the structure of the neuropeptide somatostatin. The somatostatin receptors are G protein-coupled receptors. Somatostatin receptor subtypes in humans are sstr1, 2A, 2 B, 3, 4 and 5. While normally expressed in the gastrointestinal (GI) tract, pancreas, hypothalamus, and central nervous system (CNS), they are expressed in different types of tumours. The predominant subtype in cancer cells is the sstr2 subtype, which is expressed in neuroblastomas, meningiomas, medulloblastomas, breast carcinomas, lymphomas, renal cell carcinomas, paragangliomas, small cell lung carcinomas and hepatocellular carcinomas.
As a radiopharmaceutical compound that is selective for somatostatin receptors, there is research being done to for these radiolabeled compounds to act as diagnostic tests in PET scans for neuroendocrine tumors and other tumors not previously targeted with radiolabeled somatostatin receptor agonists, and to act as radiopharmaceutical therapeutic compound, more specifically to conduct peptide radionuclide receptor therapy.
There are also some non-radiopharmaceutical compounds that are developed as competitive inhibitors of somatostatin, such as the hormone antagonist cyclosomatostatin.
Somatostatin
Somatostatin is a G protein-coupled receptor ligand. When the receptors are activated, it causes the cells where the receptors are expressed to decrease hormone secretion. Mainly, as a neuroendocrine inhibitor, it exerts its effects on gastrointestinal (GI) tract, pancreas, hypothalamus, and central nervous system (CNS), causing hormone secretions coupled to this pathway to be reduced. It can affect neurotransmission and memory formation within the central nervous system. Within human and animal models, it demonstrated its effects of preventing angiogenesis and reducing healthy and cancer cell proliferation.
Within tumors, somatostatin receptors, mostly of the ssrt2 subtype, are expressed in most neuroendocrine tumors, breast tumors, some brain tumors, renal cell tumors, lymphomas and prostate tumors.
Radiolabel
The radiolabeled somatostatin receptor antagonists share the following structure:
The antagonist has a peptide moiety. The nomenclature of the somatostatin receptor antagonists is also based on this order.
The structure of somatostatin receptor antagonists are similar to that of the agonists. Some agonists were already approved by the FDA for clinical use, such as In-DTPA-octreotide and Ga-DOTATATE. Development started after the discovery of modifications that can be done to the octreotide group, a ssrt selective subtype agonist, to cause its agonistic effects to be lost and gain antagonistic effects. Different subtype receptor antagonists were later developed.
Research has mostly been done on the sstr2 receptor antagonist, as the sstr2 receptor is expressed on most tumors. Somatostatin receptor antagonists are divided by generation based on the type of the subtype receptor antagonist. The first generation consists of sst2-ANT and BASS, which are sstr2 selective; and sst3-ODAN-8, which is selective for sstr3.
After initial results of their increased sensitivity to neurocrine tumors appeared, ssrt2 selective antagonists that had even higher affinity were developed. These were LM3, JR10, and JR11, which make up the second generation. JR11 was shown to be the most effective among these 3 antagonists, and compounds that entered further clinical development to act as a PET imaging agent or therapeutic agent carried this subtype antagonist.
The presence of a chelator coupled to the subtype antagonist was shown to have an effect on the biologic properties. Compounds were developed with 3 macrocyclic chelators: DOTA, NODAGA, and CB-TE2A. DOTA had already been used as a chelator in the radiolabeled somatostatin agonists, as well as NODAGA and CB-TE2A. Ga-NODAGA-based compounds were shown to have a higher binding affinity than its DOTA analogues. However, these somatostatin receptor antagonists showed a higher tumor uptake despite its lower affinity for ssrt receptors, due to being able to bind a receptor despite its activation status.
Compounds containing one of the radionuclides of indium-111, lutetium-177, copper-64, yttrium-80 and gallium-68 have been made. A study indicated the gallium compound had the lowest affinity to the sstr2 receptor.
Compounds list
The following listed compounds are those that have entered some phase of pre-clinical study.
Further clinical studies
Ga-NODAGA-JR11 had entered further clinical studies as an imaging agent, while and Lu-DOTA-JR11 had similar research done as a therapeutic agent, as JR11 has a high binding affinity for ssrt2 subtype receptors which are highly expressed on the surface of tumor cells. Gallium-containing agonists had already been established as an imaging agent. Lutetium-containing agonists were used as a therapeutic agent in peptide receptor radionuclide therapy, due to the lower energy electrons emitted, and γ-emission causing easier dose adjustment to patient characteristics to avoid renal damage. The NODAGA chelator was used over DOTA in Gallium antagonists due to higher binding affinity, while no Lu-NODAGA compounds were developed due to established usage of Lu-DOTA derivative agonist drugs, and poor uptake compared to DOTA, which is reverse that of the gallium-containing antagonists.
Safety
In general, somatostatin receptor antagonists were noted to be well tolerated. However, due to its mechanism of action, it may decrease the effectiveness of SSA therapy (Somatostatin Analogue Therapy), however other studies indicate SSA may not need to be stopped if somatostatin antagonists are used to label tumors instead of agonists. As somatostatin can cause inhibition of hormone production that uses it as a mediating hormone, it has an antiproliferative effect on cell tumors, especially in neuroendocrine tumors. Somatostatin analogue therapy uses longer-acting agonists than the endogenous somatostatin to extend the antiproliferative effects. Somatostatin receptor antagonists can bind to the receptors without activating them , antagonizing the therapeutic inhibitory effects of SSA therapy. Slow intravenous injection might be used until further safety data becomes available.
Somatostatin receptor agonists versus antagonists in radiolabelling
Agonists of the somatostatin receptor had been long established as an imaging agent, with the first agonist Ga-DOTATOC coming out in 2001, which is based on a radiolabeled somatostatin receptor agonist drug octreotide, and further developments were based on its structure. Agonists share the characteristic of being uptaken into tumor cells, and degraded intracellularly. Antagonists, while not widely absorbed into the tumor cells, can bind to a wider range of receptors as they can bind to the receptors regardless if the receptors are activated or inactivated. They thus are more sensitive to neuroendocrine tumors.
Another study noted the antagonists showed lowered internalization into tumors, cleared from the blood quickly, and had a higher binding to tumors, which were noted to be properties benefitting its use over agonists in detecting metastatic tumors.
A head-to-head study of the gallium-containing compounds, where the Ga-NODAGA-JR11 antagonist and Ga-DOTATOC agonist are directly compared, showed that Ga-NODAGA-JR11 had higher hepatic metastatic tumor detection rate and lesion sensitivity than Ga-DOTATOC.
Another head-to-head study of lutetium containing compound found the antagonist Lu-DOTA-JR11 bound with the receptors more quickly, had a longer retention time and unbound more slowly than the Lu-DOTA-TATE agonist.
Radiolabeled somatostatin receptor antagonists in Peptide Radionuclide Receptor Therapy (PRRT)
Somatostatin receptor antagonists are also being developed as therapeutic agents in peptide radionuclide receptor therapy (PRRT) due to the wider binding of antagonists compared to agonists. Research indicated the antagonist Lu-DOTA-JR11 showed higher tumor uptake, more double-strand breaks within tumor cells, longer adherence time to tumors and improved tumor-to-kidney dose ratio.
Moreover, another study finds out that radioactive atom, terbium-161 (161Tb), that can release short-ranged electrons, can combine with somatostatin receptor antagonists which localize at the cell membrane, giving an alternative solution, rather than the currently clinically used lutetium-somatostatin receptor agonist, which localize at the cytoplasm and nucleus. Moreover, Tb-antagonist in vitro shows 102-fold more potent than Lu-antagonist in inhibiting tumor cell growth and prolonging survival of mice, which is trusted to be due to its high linear energy transfer. This result is further repeated and confirmed in vivo, showing the high potential and strengths of radiolabeled somatostatin receptor antagonists to treat neuroendocrine neoplasms.
Further potential
Other compounds other than radiolabelled somatostatin receptor antagonists have also been studied. Cyclosomatostatin is one such compound. Contrary to previously discussed compounds, cyclosomatostatin does not contain a radionuclide. It is a non-selective somatostatin receptor antagonist, inhibiting the effects of somatostatin on target cells in the gastrointestinal (GI) tract, pancreas, hypothalamus, and central nervous system (CNS). Cyclosomatostatin is used as a research chemical to investigate the effects of somatostatin on different cell types by antagonizing its receptors. However it acts as an agonist in SH-SY5Y neuroblastoma cells.
Cyclosomatostatin is also known by the following names:
7-CPP
antagonist SRIF-A
CyCam
cyclo(7-Ahep-Phe-Trp-Lys-Thr(Bzl))
cyclo(7-aminoheptanoylphenylalanyl-tryptophyl-lysyl-benzylthreonyl)
cyclo-(7-aminoheptanoyl-Phe-D-Trp-Lys-Thr(Bzl))
Cyclosomatostatin may have the possibility of treating complications of acute hemorrhage. Hepatic insulin sensitizing substance (HISS), a hormone, will be secreted by the liver which stimulates skeletal muscle glucose uptake when responding to insulin. This action makes up around 56% of total insulin action. Hemorrhage was shown to cause insulin resistance by this type of HISS-dependent insulin resistance (HDIR). Two animal tests were done, which shows that cyclosomatostatin can help prevent HDIR without correcting the hyperglycemic condition in the situation of hemorrhage and exogenous somatostatin infusion.
Cyclosomatostatin may be related to other indications, including the potential of blocking the suppression of gastric emptying triggered by corticotropin-releasing hormone (CRH), the key regulator of the hypothalamic-pituitary-adrenal axis released to alter the body response caused by stress. Furthermore, cyclosomatostatin, even if used alone, may modulate neurotransmitter levels. It increases acetylcholine (ACh) release by reversing the inhibitory effect of a substance, DHP agonist Bay K 8844, to L-type voltage-sensitive Ca2+ calcium channel.
References
Receptor antagonists | Somatostatin receptor antagonist | [
"Chemistry"
] | 2,590 | [
"Neurochemistry",
"Receptor antagonists"
] |
72,994,605 | https://en.wikipedia.org/wiki/Rubika | Rubika () is an Iranian social media platform, instant messaging (IM), VoIP and video-on-demand service developed by Tusca holding, MCI, and MTN Irancell. It is one of the most widely used social media platforms in Iran, with more than 50 million users, and the largest social media app based in Western Asia. It is available on Android, iOS and the web. Registration requires a mobile telephone number.
History
Rubika was launched as part of efforts to provide a communication and social media platform developed by Iran. Over time, it has grown to be a widely recognized platform with a large user base with the support of major organizations like MCI and MTN Irancell. Rubika's success is reflected in its prominence as one of the most used social media apps in Iran, with an increasing focus on expanding to international markets. It was removed by Google Play in 2022 along with many other Iranian platforms. But it continues to be available through direct downloads and other app stores and through its web app, maintaining its user base. It is surveilled in part through MCI Digital platform monitoring center.
Features
The platform includes AI-driven tools and video calling with end-to-end encryption. For businesses, Rubika offers tools for advertising and customer engagement, including business pages and shopping channels. The platform includes entertainment options such as live broadcasts, TV, and video streaming, alongside a photo-sharing feature. Additionally, Rubika integrates financial services, including a built-in payment system, digital wallet and access to health insurance. Features also include dark mode and location services.
Message Exchange Bus (MXB)
Rubika is part of the Message Exchange Bus (MXB) system, which allows seamless communication between various Iranian messaging platforms, including Bale, Soroush, and Eitaa. MXB enables users send messages and files and ext. between these apps without needing a separate account for each one. This system has been made by Iran for the first time and is instrumental in creating a unified messaging ecosystem in Iran.
Social networking services
Rubika integrates traditional social media functions with messaging features, offering an all-in-one solution for users. Businesses leverage the platform for direct engagement, advertising, and e-commerce, while individuals enjoy community interactions, photo sharing, and livestreams.
Video on demand
The platform includes a robust video on demand feature, providing access to movies, series, and live TV channels. Users can enjoy personalized recommendations based on viewing habits.
See also
Bale
Eitaa
Filimo
Messaging apps
References
External links
Android (operating system) software
Instant messaging clients
Instant messaging
Internet in Iran
Video on demand services
Iranian social networking websites | Rubika | [
"Technology"
] | 553 | [
"Instant messaging",
"Instant messaging clients"
] |
72,998,181 | https://en.wikipedia.org/wiki/The%20Ark%20%28Prince%20Edward%20Island%29 | The Ark was a bioshelter constructed in Spry Point, Prince Edward Island, designed by architects David Bergmark and Ole Hammarlund, who relocated from the USA to design the project under their firm's name Solsearch Architects. The other major contributor was a New England ecological research center, called The New Alchemy Institute, which conceptualized the PEI Ark. The goal of the New Alchemy institute was to study non-violent and non-lethal methods to secure the future of humanity as stated by one of the project's participants.
The New Alchemy institute also gathered together intellectuals and activists from ecological and economic movements to promote and work on the PEI Ark Project. Precedents and inspiration for the Ark building were sourced from E. F. Schumacher's Small is Beautiful, Amory Lovins "soft energy paths" concept, and Buckminster Fuller's Operating Manual for Spaceship Earth. Construction began in 1975 and was completed in 1976. The Ark incorporated sustainable architecture technologies developed by the New Alchemy Institute. The end goal of the project was to test if a sustainable building could be built in a harsh Northern climate. A secondary objective of the Canadian government was to test green technologies.
The project was successfully built and gained international media attention in 1976. The cost of the project was $150,000 to construct. The government provided the property for the project and the federal and provincial governments gave grants consisting of a total of $350,000 for research. Four individuals lived in the Ark for about 18 months from its opening in 1976, demonstrating its potential as a residential structure. It was then used for research in alternative energy by the government of Prince Edward Island. Over the next decade it was used for various community and commercial activities, including a motel, before being sold and converted to a restaurant in 1991. The restaurant was sold in the late 1990s and the building was demolished. Today, the Inn at Spry Point stands on the former site of the Ark.
History
The Background
The PEI Ark was constructed during a wave of environmentally green Architecture across the globe. The social trends that created the interest in green architecture like the Ark; included the youth movements in the 1960s, the global activism in the 1970s, and the ongoing tension of the Cold War. The biggest contribution was the OPEC oil crisis of 1974, which began from a Cold War-era oil embargo. The Canadian government became interested in alternative sources of energy. A public discussion began about human environmental impacts, and food production drove the concept for the Ark, which was meant to demonstrate the viability of alternative energy and sustainable living practices.
The Design
The New Alchemy Institute was in charge of the project, and had already commissioned one similar building, in a farmstead in Cape Code. The PEI Ark was an attempt to create a sustainable building (similar to the Cape Code Ark) in an environment known for having very harsh weather. The New Alchemy Institute wanted to test passive design strategies in winter conditions.
Architects David Bergmark and Ole Hammarlund of Solsearch Architects were hired to design the building. They gave the building a spatial vision that wove together modern building techniques with ecological systems. The building was a precursors to modern green design.
The Canadian Government and Opening
In 1974 the PEI Arks concept was established with the technical and financial support of the Canadian federal government's Department of Urban Affairs and Environment Canada's Advanced Concepts unit. The PEI government was interested in exploring alternative building development in PEI. Tests were successfully done on the buildings active green systems.
The Ark was inaugurated in 1976 by then-Prime Minister Pierre Trudeau. Its opening was also attended by PEI premier Alex Campbell, and various traditional and counterculture groups. The Ark was a popular destination for tourists in the immediate years after its opening.
The Ark's Legacy
The Ark was inhabited for 18 months after opening. Ownership was then passed to a provincial agency that used it to test alternative energy. Governmental changes in the following years, with growing disinterest in sustainable buildings, and the difficulty of creating similar buildings caused disinterest in the Ark after a few years. The Ark was repurposed multiple times in the next decade, as a restaurant, community center, bed and breakfast, and motel.
In the 1990s the building was sold and demolished. In its wake, an Inn was constructed.
Architectural Design
Sustainable Architectural Technologies used
Solar panels that would be used to collect the sun’s energy that would be stored and used, a wind turbine that would generate electricity to be stored and used as addition electrical source, a rock and water heat storage system was used for heat exchange (was located in the basement), insulation heavily fortified the walls and roof system, south facing windows, ultraviolet and infrared-permeable glazing was used on the greenhouse windows, windows located on the greenhouse side that were angled in a way to reflect more winter sunlight onto the solar panels. A greenhouse was incorporated for human and fish food, and was also used as another source to dump waste / manage compost. Giant water tanks to house fish for food production, and heat retention. Locally sourced materials such as wood were used to frame and clad the structure. In addition the thermal mass of the building allowed solar heating to partake throughout the structure. And appliances (mainly consisting of kitchen appliances) that were highly regarded as the “most efficient” of its time were used. An example of an efficient appliance is a wood stove
About the Ark design
For being in the time era of the 1970’s, the bioshelter’s design was ahead of its time. It offered a self-sustainable to a built environment for a family to live in (family consisting of 4 individuals), and provided all the essential living conditions needed to thrive such as food requirements, energy needs, and waste management. The resulting design properties enabled the individuals who inhabited the building to engage in the ecosystems of their living environment as a new means of lifestyle.
Located on the south side of the Ark’s spatial layout was the greenhouse. The greenhouse space had numerous planting beds to accommodate the growth of healthy plants to eat such as vegetables. In addition to this greenhouse space, there were also large containers (water tanks) which housed fish that were used to farm as another source of food. Both plant and fish worked in cohesion with one another as off trimmings from the plants would be part of the food used to feed the fish. And the tank water which consisted of the byproducts (excrements) of the fish and other organic matter was used as another source of nutrients to aid plant growth.
Further reading
References
External links
PEI Ark Catalogue
Architecture (CCA), Canadian Centre for. "It's All Happening So Fast"
Buildings and structures in Prince Edward Island
Buildings and structures completed in 1976
Greenhouses in Canada
Artificial ecosystems
Sustainable architecture
Sustainable building
Architecture related to utopias | The Ark (Prince Edward Island) | [
"Engineering",
"Biology",
"Environmental_science"
] | 1,401 | [
"Artificial ecosystems",
"Sustainable building",
"Sustainable architecture",
"Building engineering",
"Construction",
"Architecture related to utopias",
"Ecosystems",
"Environmental social science",
"Architecture"
] |
72,998,928 | https://en.wikipedia.org/wiki/Enterobacterial%20common%20antigen | The enterobacterial common antigen (ECA) is a carbohydrate antigen found in the outer membrane of many Enterobacterales species. The antigen is unanimously absent from other gram-negative and gram-positive bacteria. Aeromonas hydrophila 209A is the only organism outside of Enterobacterales that expresses the ECA. More studies are needed to explain the presence of the antigen in this species as no other strains of this species express the antigen. The ECA is a polysaccharide made of repeating units of trisaccharides. The functions of these units have very few proven functions. Some evidence indicates role in pathogenicity in the bacteria that present the ECA. There are three separate types of ECA these include ECAPG, ECALPS, and ECACYC, each have different lengths. The synthesis of the ECA is controlled by the wec operon and has a 12-step synthesis which is described below. Due to the lack of proven function of the ECA, any clinical significance is hard to define however, some evidence suggests that human serum has antibodies against ECA.
History
The ECA was first described in 1962 in a paper written by Calvin M. Kunin and colleagues. When documenting strains of E. coli responsible for urinary tract infections, Kunin exposed these E. coli strains to rabbit antisera and various other E. coli strains (102 homologous and heterologous strains). Using passive agglutination, Kunin detected the O-antigen found in the lipopolysaccharide (LPS) of E. coli. During the experiments, Kunin noticed that there was cross-reactivity between the rabbit antisera and many of the E. coli strains. One of the sera, O14, reacted to an antigen found in a large range of E. coli strains. Notably, the antigen was not attached to the O-antigen of the LPS. The team noted that this antigen was observed in several other enteric (gram negative) bacteria strains and absent in many gram-positive strains. Kunin wanted to name the antigen the Common Antigen (CA) but his team convinced him to reconsider as to avoid confusion with the abbreviation for cancer. Thus, with a more specific name, the antigen was named the Enterobacterial Common Antigen (ECA). However, the ECA is not necessarily expressed in all enteric species. Many endosymbionts from Enterobacterales have lost the genes necessary for ECA synthesis. Additionally, Aeromonas hydrophila 209A is the only organism outside of Enterobacterales that expresses the ECA. Yet, more studies are needed to explain the presence of the antigen in this species as no other strains of this species express the antigen. Research on the ECA continues to develop.
Gene
The genes the regulate and control the synthesis of the ECA are located within on operon called the wec operon. The operon starts at 85.4 centisommes on the Escherichia coli K-12 chromosome. In regards to ECA, the wec operon has multiple genes that play important parts in inhibition as well as assembly of the ECA; these include but are not limited to wecB, wecC, wecD, wecE, wecA, and wecG.
Structure
The polysaccharide of the enterobacterial common antigen (ECA) is composed of repeating units of a trisaccharide. This trisaccharide is made of N-acetylglucosamine (GlcNAc), N-Acetyl-D-Mannosaminuronic Acid (ManNAcA), and 4-acetamido-4,6-dideoxy-D-galactose (Fuc4NAc). GlcNAc is connected to ManNAcA via an alpha 1,4 linkage. ManNAcA is connected to Fuc4NAc via a beta 1,4 linkage. Each full trisaccharide unit is connected to each other by an alpha 1,3 linkage from Fuc4NAc to GlcNAc.
There are three types of fully formed ECA: ECAPG, ECALPS, and ECACYC. Regardless of the length, the polysaccharide is attached to a diacylglycerol with a phosphodiester bond and sits on the outer membrane of the bacterium. Like the ECAPG, the ECALPS sits on the outer membrane of the bacterium and is attached to a lipid. The ECALPS is not only attached to a lipid but also an LPS core. The final type of ECA is ECACYC, which is different from the other two types in that it is found only in the cytoplasm, and is composed of the polysaccharide bound in a ring. Another distinguishing characteristic of ECACYC is the total length of the trisaccharide chain; ECACYC is usually 4 to 6 units long, while ECALPS and ECAPG range from 1 to 14 units long.
Synthesis
The three types of ECA have different qualities, but altogether share some basic features, the most important is the synthesis of the ECA unit. The synthesis of a unit of ECA is carried out by multiple enzymes. Each monosaccharide that makes up a unit is carried by an undecaprenyl phosphate (UDP) to a lipid carrier made of approximately 55 isoprenoid units in the inner membrane. Each monosaccharide is added to the lipid carrier to make a trisaccharide attached to a lipid. The enzymes that catalyze the group transfers of the monosaccharides from undecaprenyl phosphate to the forming ECA trisaccharide unit are Wec enzymes. The details of the synthesis are as follows:
Step 1: WecA takes GlcNAc from UDP-GlcNAc and attaches GlcNAc-1-phosphate to an isoprenoid carrier. The product is called Lipid IECA.
Step 2: WecB takes UDP-GlcNAc and epimerizes it at carbon 2. This makes UDP-N-acetylmannosamine.
Step 3: WecC forms UDP-ManNAcA from the UDP-N-acetylmannosamine (from step 2) by reducing NAD+ to NADH.
Step 4: WecG takes the ManNAcA from UDP-ManNAcA (from step 3) and adds it to Lipid IECA (From step 1). The product of this group transfer is Lipid IIECA. At this point, 2 of the 3 carbohydrates that make the repeating unit of ECA are connected. The next steps (steps 5–8) prepare the final monosaccharide to be transferred to Lipid IIECA to make Lipid IIIECA, which has one full ECA trisaccharide unit.
Step 5: Glucose-1-phosphate, dTTP, and a H+ combine in a reaction catalyzed by RmIAECA to make dTDP-glucose.
Step 6: NAD+ acts as a cofactor for the enzyme RmIBECA to convert dTDP-glucose (from step 5) into dTDP-4-keto-6-deoxy-D-glucose. This happens through a series of redox reactions and a dehydration reaction.
Step 7: WecE adds an amino group from a glutamate residue to dTDP-4-keto-6-deoxy-D-glucose (from step 6) to make dTDP-4-amino-4,6-dideoxy-a-D-galactose (dTDP-Fuc4N)
Step 8: Acetyl-CoA acts as a cofactor for the enzyme WecD, which makes dTDP-Fuc4NAc acetylating dTDP-Fuc4N (from step 7).
Step 9: WecF takes Fuc4NAc from dTDP-Fuc4NAc (from step 8) and adds it to Lipid II (ECA), to make Lipid IIIECA. At this point, the complete trisaccharide unit is on the cytoplasmic side of the inner membrane attached to a lipid carrier (Lipid IIIECA). The final synthesis step, polymerization, occurs on the periplasmic side of the inner membrane.
Step 10: WzxE, a flippase, flips Lipid III from the cytoplasmic side of the inner membrane to the periplasmic side of the inner membrane.
Step 11: WzyE polymerizes the ECA trisaccharides by taking the ECA unit from the lipid carrier and WzxE. The lipid carrier is returned to the cytoplasmic side of the membrane to create another ECA trisaccharide unit.
Step 12: The growing ECA chain is stopped at the correct length by WzzE through an unknown mechanism. The product of these 12 steps is a long chain of ECA units attached to an isoprenoid lipid carrier. From here, the ECA polysaccharide is specialized into the type of completed ECA it will be.
To make ECAPG, the ECA polysaccharide is taken from the isoprenoid lipid carrier and given to a different, unknown lipid. The final product, ECAPG, is an ECA polymer linked by a phosphodiester bond to a diacylglycerol.
To make ECALPS, WaaL, takes the ECA polysaccharide from the isoprenoid carrier and gives it to the core oligosaccharide of LPS. The synthesis of ECA in general shares many steps for the synthesis of LPS. The most significant overlap is the use of the WzxE and the WzzE proteins.
The mechanism by which ECACYC is made is largely unknown. It has been previously established that ECACYC is synthesized in the periplasm and that this mechanism involves WzzE. From there, ECACYC is transported back across the inner membrane to the cytoplasm by a mechanism that has not yet been determined.
Function
Due to the close association of ECA biosynthesis and other processes like O-antigen and peptidoglycan synthesis, it is difficult to define specific functions of the ECA in different species. Enterobacterales species that have been cultured for prolonged periods show a significant reduction in O-chain synthesis while maintaining ECA stability. Several gene-knockout experiments show that upon altering genes participating in the synthesis of ECA, new sensitivities are observed. It is accepted that the ECA plays a role in pathogenicity.
Clinical significance
The ECA occurs across all Enterobacterales species but very few species have antibodies to the antigen. This indicates that while all strains possess antigenic ECA, very few strains produce immunogenic ECA.
Many studies reported low concentrations of ECA antibodies present in human serum occurred before ECA knockout strains were available. The reported values are a combined titer of the ECA antibodies as well as the antibodies that are bound to protein antigens that are shared among Enterobacterales. ECA antibodies have been detected in human serum after infection by E. coli, Yersinia enterocolitica O3 strains, or Proteus mirabilis-associated arthritis patients.
Several studies have sought to identify how significant a role the ECA plays in pathogenicity, even under experimental conditions, the protection offered by an antibody response was slight and temporary in both active and passive immunization.
References
Antigens | Enterobacterial common antigen | [
"Chemistry"
] | 2,466 | [
"Antigens",
"Biomolecules"
] |
72,999,437 | https://en.wikipedia.org/wiki/Handbook%20of%20Tyranny | Handbook of Tyranny is a 2018 non-fiction book by Theo Deutinger. It documents how architecture is used to protect and control humans and animals.
Publication
Handbook of Tyranny, is written by architect and cartographer Theo Deutinger and published by Lars Müller Publishers in 2018. It has 160 pages.
Synopsis
The book documents the architecture of refugee camps, prisons, slaughter houses, and border fences and how they are used to control animals and people. It illustrates architectural features used to prevent human migration, suicide, terrorism, and illicit drug injection. Themes include nationalism, terrorism, corporate power, and economic globalisation.
The format of each chapter incorporates explanatory text and annotated graphics. It also incorporates two essays, one by American journalist Brendan McGetrick. The presentation of data mimics the styles that Ernst Neufert used in his 1936 reference book Architects' Data.
Critical reception and influence
Aaron Betsky described the "deeply ironic beauty" of the book, which he also calls terrifying and notes how "ingenious we have become at harming others through both architecture."
The book won the Festival international du livre d'art et du film book award for architecture in 2018.
The book inspired a Carleton University architecture student's project Machine Atlas, which won the Architect Magazine's 2020 Studio Prize. Machine Atlas featured illustrations on extractivism.
References
2018 non-fiction books
Works about architecture
Books about human rights | Handbook of Tyranny | [
"Engineering"
] | 294 | [
"Works about architecture",
"Architecture"
] |
73,002,590 | https://en.wikipedia.org/wiki/Outbuilding | An outbuilding, sometimes called an accessory building or a dependency, is a building that is part of a residential or agricultural complex but detached from the main sleeping and eating areas. Outbuildings are generally used for some practical purpose, rather than decoration or purely for leisure (such as a pool house or a tree house), although luxury greenhouses such as orangeries or ferneries may also be considered outbuildings. This article is limited to buildings that would typically serve one property, separate from community-scale structures such as gristmills, water towers, fire towers, or parish granaries. Outbuildings are typically detached from the main structure, so places like wine cellars, root cellars and cheese caves may or may not be termed outbuildings depending on their placement. A buttery, on the other hand, is never an outbuilding because by definition is it is integrated into the main structure.
Separating these work spaces from the main home "removed heat, obnoxious odors, and offending vermin" and decreased the risk of house fires and food-borne illnesses. The study of historical outbuildings also offers information about the lives of workers otherwise excluded from the history of a place, since one possible purpose of an outbuilding was to reinforce class boundaries.
Outbuildings are typically constructed in a vernacular architectural style. Outbuildings can be valuable resources for architectural historians as they may "offer insight unavailable in traditional documentary sources." Architectural historian William Tishler argues that in addition to documenting outbuildings, researchers need to inspect attics and basements "because it's there that you see how things are put together."
Researchers studying detached kitchens in Wiltshire identified some common characteristics of the outbuildings: non-standard floor plans, no large windows, location near the main house, footprint smaller than main house, and little or no interior ornamentation.
Types
Bunkhouses
Slave quarters
Tenant housing
Itinerant labor housing
Bothies
Wash houses
Saunas
Lavoirs (laundries)
Wood sheds
Radio shacks
Barns, possibly incorporating haylofts and/or outdoor animal pens
Stables for horses
Mangers
Hay barracks
Outhouses or privies
Spring houses
Ice houses
Pump houses or windpumps
Tankhouses
Summer kitchens, detached kitchens, cookhouses, dirty kitchens, etc.
Bake ovens
Smokehouses
Root cellars
Cold storage
Pit-houses
Dugout (shelter)
Wine cellars and wine caves
Cheese caves
Butcher houses (after an outdoor slaughter, preparing the cuts of meat for long-term storage would take place in a butcher house)
Poultry houses
Pigpens or piggeries
Milkhouses or dairy barns
Shearing sheds
Dovecotes, columbaria, pigeonniers
Dog houses, kennels
Siloes
Granaries grain bins
Corn cribs
Rice barns, winnowing barns
Hemp-processing houses
Threshing barns
Potato houses
Greenhouses
Illicit grow houses (marijuana, psilocybin mushrooms, et al.)
Detached conservatories, orangeries, walipinis, pineapple pits, ferneries, etc.
Coach houses
Machine houses and tool sheds
Packhouses
Drying sheds, dry houses
Kilns
Forges or smithies
Sugar shacks
Oast houses, malt houses
Cider houses
Still sheds
Tobacco barns
Gin house (for a cotton gin)
Guard houses
Guest houses
Workshops
shed
Detached garages
Scale sheds
Roadside stands
Garage
Storage room
Ware house
Barn subtypes
See also
Well
Cistern
Croft
Connected farm
Barnyard
Shed
Hut
Lean-to
Pergola
:Category:Pastoral shelters
Chashitsu (Japanese tea houses)
Grillkota (Scandinavian grillhouses)
Derivative extravagance
Folly
Garden hermit
References
Further reading
Buildings and structures
Vernacular architecture | Outbuilding | [
"Engineering"
] | 748 | [
"Buildings and structures",
"Architecture"
] |
73,002,936 | https://en.wikipedia.org/wiki/Chinese%20uniformity | Chinese uniformity () is a term referring to the traditional phenomenon and political thought of uniformity and unification in the Chinese history. Since the Western Zhou dynasty (–771 BC) there has been a uniformity of various systems in the land of China, including the uniformity of the calendar, the uniformity of decrees, the uniformity of thought, the uniformity of etiquette, the uniformity of metrology, and the uniformity of writing system. The Qin dynasty (221 BC–206 BC) was the first imperial Chinese dynasty to reign over a unified China following its wars of unification. Since then China has a long history of a unified empire in addition to a common culture and traditions shared by many Chinese. Confucianism became China's official ideology in education and court politics during the Han dynasty. Even though Chinese people spoke a variety of dialects, the literate classes shared a written language known as the Classical Chinese, and an examination system based on Chinese classics served as the main path to official positions since the Sui dynasty.
See also
Chinese Empire
Mandate of Heaven
Dynasties of China
Dynastic cycle
Zhonghua minzu
References
Conformity
Classical Chinese philosophy
Political history of China | Chinese uniformity | [
"Biology"
] | 243 | [
"Behavior",
"Conformity",
"Human behavior"
] |
73,002,993 | https://en.wikipedia.org/wiki/Zoubeida%20Ounaies | Zoubeida Ounaies is a Tunisian mechanical engineer, whose research involves nanocomposites, smart materials, and piezoelectricity in polymers. She is a professor of mechanical engineering at Pennsylvania State University, affiliated with the Penn State Intercollege Graduate Degree Program in Materials Science and Engineering and with the Institute of Energy and the Environment. At Penn State, she is director of the Convergence Center for Living Multifunctional Material Systems, and acting director of the Materials Research Institute.
Education and career
Ounaies grew up in Tunisia, the daughter of an engineer. She went to Pennsylvania State University for her undergraduate and graduate education, funded by the Tunisia Technology Transfer Program of the United States Agency for International Development, and completed her Ph.D. in 1996.
After postdoctoral research at NASA's Langley Research Center from 1997 to 2001, she returned to Penn State as a faculty member in 2001. She moved to Texas A&M University in 2005, but returned to Penn State again in 2011.
Recognition
Ounaies is an ASME Fellow, elected in 2016. She is also a Fellow of SPIE, the International Society for Optics and Photonics.
References
External links
Year of birth missing (living people)
Living people
American materials scientists
Women materials scientists and engineers
American women engineers
Tunisian engineers
Tunisian women engineers
Pennsylvania State University alumni
Pennsylvania State University faculty
Texas A&M University faculty
Fellows of the American Society of Mechanical Engineers
Fellows of SPIE | Zoubeida Ounaies | [
"Materials_science",
"Technology"
] | 293 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
73,006,033 | https://en.wikipedia.org/wiki/Anke%20Blume | Anke Blume (b. 6 April 1969) is an engineering technology professor at the University of Twente known for her contributions to silica and silane chemistry for rubber applications.
Education
Anke Blume was born in Hanover, Germany, April 6, 1969.
Blume studied chemistry at Leibniz University in Hannover, earning a master's degree in July 1993. She went on to complete doctoral studies at the German Institute for Rubber Technology (DIK), finishing in 1995 and continuing for a 9-month term as a post-doc.
Career
Blume began an industrial career in 1996 as a chemist with the product development group at silica supplier Degussa AG (later to become Evonik). In 2011, she managed intellectual property for silica and silane in rubber applications.
Blume's academic career began when she joined the University of Twente in 2013, as Chair of Elastomer Technology and Engineering (ETE) Group. She has been noted for her contributions to rubber technology aimed at reduction, in particular for automotive lightweighting and for tire rolling resistance reduction. She was invited to a jury that judged Nokian Tyres sustainability innovation challenge. She also served on the panel that selected the Tire Technology International Awards for Innovation and Excellence. Blume was elected to serve as head of the German Rubber Society's western group, DKG West, for the term 2018–2021.
Awards
2023 - Melvin Mooney Distinguished Technology Award from ACS Rubber Division
References
Polymer scientists and engineers
Living people
Women materials scientists and engineers
People from Hanover
Year of birth missing (living people) | Anke Blume | [
"Materials_science",
"Technology"
] | 329 | [
"Women materials scientists and engineers",
"Materials scientists and engineers",
"Women in science and technology"
] |
73,007,073 | https://en.wikipedia.org/wiki/Herman%20Bouwer | Herman Bouwer (1927–2013) was a hydrological scientist who worked in groundwater hydrology and water resources management, with a specialization in the area of Managed Aquifer Recharge (MAR). He was born in the Netherlands and moved to the United States in 1952 to study for his PhD at Cornell University. He went on to work at the U.S. Water Conservation Laboratory, U.S. Dept. of Agriculture, serving as director from 1972 to 1990. His research efforts on characterizing and modeling the movement of water and pollutants in the vadose zone and groundwater resulted in field and analytical methods that are used in the groundwater sciences. He authored or co-authored over 300 publications and wrote the textbook Groundwater Hydrology.
As a hydrogeologist, Bouwer is credited as "one of the first to bridge the gap between engineering, soil physics, and hydrogeology."
Early life and education
Herman Bouwer was born and raised in Haarlem, the Netherlands, in 1927, and was a teenager under German occupation during World War II.
After the war, Bouwer enrolled in the Agricultural University in Wageningen, Netherlands, and received a BS degree and a MS degree in drainage and irrigation in 1952. As a graduate student at Cornell University he conducted research in how to drain the waterlogged soils of central New York and received his PhD in agricultural and civil engineering and agronomy in 1955.
Career
He accepted a faculty position in the Agricultural Engineering Department at Auburn University, where he also served as an associate agricultural engineer for the Auburn Agricultural Experiment Station. In Auburn, he conducted research on unsaturated flow using resistance network analogs to solve soil physics problems prior to the development of analytical and numerical models in the groundwater sciences in the 1970s and 1980s.
In 1959, Bouwer took a position at the U.S. Water Conservation Laboratory in Phoenix, Arizona; in that position he analyzed surface water/ground water interactions including seepage from irrigation canals, groundwater mounding below groundwater recharge facilities, the effect of mounding on groundwater recharge rates and effect of ground water pumping on stream flow. Using analog resistance networks, he developed several field methods for measuring saturated hydraulic conductivity to include the double tube permeameter, falling head seepage meter, pit bailing method, air entry permeameter, Bouwer-Rice slug test in unconfined aquifers, and the single-ring cylinder infiltrometer with correction for lateral divergence and hydraulic gradients.
Bouwer helped to develop the science and application of managed aquifer recharge (MAR) and soil aquifer treatment (SAT) in the United States. His MAR and SAT research started in 1967 with the construction of the Flushing Meadows project in the dry Salt River bed in Phoenix. This was a field laboratory to study groundwater recharge using secondary treated sewage effluent. The research included studies on hydraulic loading rates, soil clogging, virus and bacteria removal, nutrient removal, nitrification-denitrification reactions, and trace organics and pharmaceutical products. His research demonstrated that soil and biological interactions in the river bed improved the sewage effluent water quality and could be adjusted through SAT wetting and drying cycles. Groundwater recharge and reuse, including potable use, would become the focus of much of his work and interests for the rest of his career.
His research work had a major impact on groundwater issues in the American Southwest and in Arizona in particular. His methods using managed soil-beds to filter treated sewage effluent (greywater) to the degree that it can be reused to irrigate food crops was able to "stretch" the city of Phoenix's "water supply at half the per gallon cost." Additionally non-soil-bed treated effluence can be used for non-edible crops like cotton. The Arizona Reporter newspaper wrote that his technology could "boost Phoenix's annual freshwater supply by as much as 40,000 acre feet. By 1967 the Salt River Project Flushing Meadows recharge field was producing 70,000 acre feet of filtered water for non-food crops, and at that time it was expected to treat up to 300,000 acre feet. The pilot plant consisted of a series of 6 recharge basins, each being 700 feet long by 20 feet wide. After percolating ten feet below the surface the water, it was purified, however Bouwer recommended at least 30 feet of percolation for safety considerations. Bouwer stated of the project that the earth "has always been nature's water purifier." By 1980, the technology developed to the degree that effluent water was re-purified through nanofiltration methods, recharged via injection wells into the ground and stored in aquifers.
During his lifetime, Bouwer authored or co-authored over 300 journal articles, wrote 12 book chapters. and also taught as an adjunct faculty member of both the University of Arizona and Arizona State University. He contributed many scientific articles to the journal Groundwater. As an educator, he taught courses and held seminars on artificially-engineered groundwater recharge in North Africa (Morocco, Tunisia) the Middle East (Jordan), India and the United States. He also traveled to other countries, including Cyprus, Morocco and India, to teach waste-water reuse techniques. In the U.S., Bouwer advised other states, for example Florida, on sewage disposal through soil-percolation reclamation processes. His textbook, Groundwater Hydrology, was published in 1978 by McGraw-Hill.
He died on July 28, 2013, at the age of 86 from Parkinson's disease complications.
Awards
Bouwer received two USDA Superior Service Awards; the Walter L. Huber Civil Engineering Research Prize from the American Society of Civil Engineers; the Prince Sultan bin Abdulaziz International Prize for Water in 2004 in the area of artificial groundwater recharge; the Arizona Hydrological Society Lifetime Achievement Award; and the National Ground Water Association Life Member Award in 1992 for his service contributions to the field of groundwater. He received, in 2007, a Lifetime Achievement Award at the 6th International Symposium on Managed Aquifer Recharge. The United States Department of Agriculture named Bouwer a Scientist of the Year.
Legacy
Bower is considered to be one of the first hydrogeologists "to bridge the gap between engineering, soil physics, and hydrogeology. "
Bouwer helped to establish the Biennial Symposium on Managed Aquifer Recharge (BSMAR), the International Symposium on Managed Aquifer Recharge (ISMAR), the Arizona Hydrological Society (AHS) and AHS Foundation.
The Herman Bouwer Award is named for him; it was established in 2000 by the Groundwater Resources Association of California and the Arizona Hydrological Society. The award is a scholarship for students in the field of hydrology and water resources.
References
Further reading
Raats, P. A. C.; Feddes, R. A. Contributions by Jans Wesseling, Jan van Schilfgaarde, and Herman Bouwer to effective and responsible water management in agriculture. Agricultural Water Management, [s. l.], v. 86, n. 1/2, p. 9–29, 2006.
External links
Managed Aquifer Recharge
Autobiography of Herman Bouwer
American hydrologists
20th-century American scientists
Scientists from Haarlem
1927 births
2013 deaths
Cornell University alumni
Environmental scientists
Hydrogeologists | Herman Bouwer | [
"Environmental_science"
] | 1,552 | [
"American environmental scientists",
"Environmental scientists"
] |
73,007,075 | https://en.wikipedia.org/wiki/Geh%C5%8Dbako | A is a box that contains many magical items traditionally used by miko, and Itako.
It means , in reference to practices outside of Buddhist teachings. It is a box which contains secret items representative of a protective spirit, or kami. It has been described as "parallel [to] the siberian shaman's drum as a source of power They have been described as representing a pre-Buddhist shamanism. It is often used for healing people.
It is believed at some point in premodern times most miko had human skulls in their gehōbako from people who promised their skulls to them, but this practice declined over time
Dolls for Kuebiko and Kangiten were often found in them in the 1960s.
Gehōbako were common among wandering miko
References
External links
Magic items
Miko
Shamanism in Japan
Shinto religious objects | Gehōbako | [
"Physics"
] | 174 | [
"Magic items",
"Physical objects",
"Matter"
] |
55,995,894 | https://en.wikipedia.org/wiki/Eryniopsis%20lampyridarum | Eryniopsis lampyridarum is an entomopathogenic fungus and its host is the soldier beetle, either Chauliognathus marginatus or Chauliognathus pensylvanicus. Eryniopsis lampyridarum is mind controlling for the soldier beetle and can manipulate the beetle into doing things that it wouldn't normally do. Once the fungus has established itself inside the beetle, it sends the infected beetle on a mission to find a specific daisy flower Asteraceae. The soldier beetle will clamp its mouthpiece onto the flower as tight as it can, while it awaits its death. The parasitic fungus forces the dead beetle to then spread its wings wide in a dramatic pose; this makes the beetle look bigger as if it is seeking out a mate. The fungus makes sure the dying beetle will attract more beetles so it can spread its spores. The fungus makes sure the beetle spreads its wings only at daybreak. It is also strange that the beetle will be dead for hours and then suddenly it will spread its wings at daylight, just in time to attract potential mates to its dead body. This is because the fungus is in control of the beetle's body functions. Then, when an uninfected beetle comes along to socialize with the dead beetle, the fungus' spores spread to the new beetle.
Not all beetles will end up at a daisy flower. Some will die and fall to the ground. In this case, the parasitic fungus creates many spores that will be resistant to the environment and remain infective for many months. The spores will remain infective in the soil, awaiting the next season where they can infect more soldier beetles.
This parasite was first discovered in North Carolina in the late 1970s, early 1980s. It has been found only in eastern and central North America, although its host, the soldier beetle, is found in southern Canada as well.
References
Parasitic fungi
Entomophthorales
Fungus species | Eryniopsis lampyridarum | [
"Biology"
] | 397 | [
"Fungi",
"Fungus species"
] |
55,996,819 | https://en.wikipedia.org/wiki/Pi%20electron%20donor-acceptor | The pEDA parameter (pi electron donor-acceptor) is a pi-electron substituent effect scale, described also as mesomeric or resonance effect. There is also a complementary scale - sEDA. The more positive is the value of pEDA the more pi-electron donating is a substituent. The more negative pEDA, the more pi-electron withdrawing is the substituent (see the table below).
The pEDA parameter for a given substituent is calculated by means of quantum chemistry methods. The model molecule is the monosubstituted benzene. First the geometry should be optimized at a suitable model of theory, then the natural population analysis within the framework of Natural Bond Orbital theory is performed. The molecule have to be oriented in such a way that the aromatic benzene ring is perpendicular to the z-axis. Then, the 2pz orbital occupations of ring carbon atoms are summed up to give the total pi- occupation. From this value the sum of pi-occupation for unsubstituted benzene (value close to 6 in accord to Huckel rule) is subtracted resulting in original pEDA parameter. For pi-electron donating substituents like -NH2, OH or -F the pEDA parameter is positive, and for pi-electron withdrawing substituents like -NO2, -BH2 or -CN the pEDA is negative.
The pEDA scale was invented by Wojciech P. Oziminski and Jan Cz. Dobrowolski and the details are available in the original paper.
The pEDA scale linearly correlates with experimental substituent constants like Taft-Topsom σR parameter.
For easy calculation of pEDA the free of charge for academic purposes written in Tcl program with graphical user interface AromaTcl is available.
Sums of pi-electron occupations and pEDA parameter for substituents of various character are gathered in the following table:
References
Chemical bond properties
Organic chemistry
Quantum chemistry | Pi electron donor-acceptor | [
"Physics",
"Chemistry"
] | 422 | [
"Chemical bond properties",
"Quantum chemistry",
"Quantum mechanics",
"Theoretical chemistry",
" molecular",
"nan",
"Atomic",
" and optical physics"
] |
55,996,822 | https://en.wikipedia.org/wiki/COBRA%20%28radar%29 | COBRA COunter Battery RAdar is a Counter-battery radar system developed jointly by Thales, Airbus Defence and Space and Lockheed Martin for the French, British and German Armed Forces. It is a mobile Active electronically scanned array 3D radar based on a wheeled chassis for the purpose of enemy field artillery acquisition.
There are believed to be about 20,000 Gallium arsenide integrated circuits in each antenna. This enables the equipment to produce the locations of multiple enemy artillery at extremely long ranges, and the radar is able to cope with saturation type bombardments. In addition there is a high degree of automated software, with high speed circuitry and secure data transmission to escape detection from enemy electronic countermeasures.
For the COBRA mid-life upgrade (2024+) an inertial navigation system from iMAR Navigation is used.
Operators
Current operators
(10)
10 purchased
(9)
12 purchased, one donated to Ukraine in 2022, 2 sold to Turkey.
(5 donated by the UK)
The radars were donated by the UK in 2016, when the Army decided that the system was redundant with the Saab ARTHUR.
(4)
In 2017, the German government approved the export of COBRA radars to Saudi Arabia.
(2)
Radars purchased from Germany in 2007.
(1)
In May 2022, it was reported that Ukraine had requested 40 COBRA systems from Germany amid the 2022 Russian invasion of Ukraine. One COBRA system was delivered later in September 2022.
(3)
3 ordered in 2009
Former operator
7 purchased, 5 donated to Jordan.
See also
AN/TPQ-36 Firefinder radar
AN/TPQ-37 Firefinder radar
Swathi Weapon Locating Radar
Aistyonok
References
Ground radars
Weapon locating radar
Counter-battery radars
Warning systems | COBRA (radar) | [
"Technology",
"Engineering"
] | 360 | [
"Warning systems",
"Safety engineering",
"Measuring instruments",
"Weapon locating radar"
] |
55,997,108 | https://en.wikipedia.org/wiki/Desidustat | Desidustat (INN, also known as ZYAN1) is a drug for the treatment of anemia of chronic kidney disease. This drug with the brand name Oxemia is discovered and developed by Zydus Life Sciences. Desidustat reduces the requirement of recombinant erythropoietin (EPO) in anemia, and decreases EPO-resistance, by reducing IL-6, IL-1β, and anti-EPO antibodies. The subject expert committee of CDSCO has recommended the grant of permission for manufacturing and marketing of Desidustat 25 mg and 50 mg tablets in India, based on some conditions related to package insert, phase 4 protocols, prescription details, and GCP. Clinical trials on desidustat have been done in India and Australia. In a Phase 2, randomized, double-blind, 6-week, placebo-controlled, dose-ranging, safety and efficacy study, a mean hemoglobin increase of 1.57, 2.22, and 2.92 g/dL in desidustat 100, 150, and 200 mg arms, respectively, was observed. The Phase 3 clinical trials were conducted in chronic kidney disease patients which were not on dialysis as well as on dialysis. Desidustat is developed for the treatment of anemia as an oral tablet, where currently injections of erythropoietin and its analogues are drugs of choice. Desidustat is a HIF prolyl-hydroxylase inhibitor. In preclinical studies, effects of desidustat was assessed in normal and nephrectomized rats, and in chemotherapy-induced anemia. Desidustat demonstrated hematinic potential by combined effects on endogenous erythropoietin release and efficient iron utilization. Desidustat can also be useful in treatment of anemia of inflammation since it causes efficient erythropoiesis and hepcidin downregulation. Desidustat has been shown to have significant effect in the treatment of complement-mediated diseases. Complement activation-induced membrane attack complex (MAC) formation and Factor B activity were also reduced by desidustat treatment. Owing to this mechanism, desidustat can be an effective therapy against membranous nephropathy and retinal degeneration, since it specifically inhibited alternative complement system, without affecting the lectin-, or classical complement pathway. In January 2020, Zydus entered into licensing agreement with China Medical System (CMS) Holdings for development and commercialization of desidustat in Greater China. Under the license agreement, CMS will pay Zydus an initial upfront payment, regulatory milestones, sales milestones and royalties on net sales of the product. CMS will be responsible for development, registration and commercialization of desidustat in Greater China. National Medical Products Administration of China (NMPA) accepted the new drug application for desidustat on 23 April 2024. It has been observed that desidustat protects against acute and chronic kidney injury by reducing inflammatory cytokines like IL-6 and oxidative stress. A clinical trial to evaluate the efficacy and safety of desidustat tablet for the management of COVID-19 patients is ongoing in Mexico, wherein desidustat has shown to prevent acute respiratory distress syndrome (ARDS) by inhibiting IL-6. Zydus has also received approval from the US FDA to initiate clinical trials of desidustat in chemotherapy Induced anemia (CIA). Desidustat was successfully introduced as an alternative treatment in patient of endogenous erythropoietin (EPO)-induced pure red cell aplasia (PRCA) due to anti-EPO antibodies. This led to a substantial and sustained improvement in hemoglobin levels, emphasizing the crucial role of desidustat intervention in EPO-induced PRCA cases. Zydus Lifesciences and Sun Pharmaceuticals have entered an agreement in October 2023 to co-market Desidustat. Sun Pharma will sell the drug as Rytstat, while Zydus will continue to sell it as Oxemia. Zydus Lifesciences is launching a proof-of-concept Phase 2a clinical trial to evaluate the safety and efficacy of desidustat in people with sickle cell disease (SCD). The study is the result of a collaboration with the Indian Council of Medical Research (ICMR)
References
Experimental drugs
4-Quinolones
Cyclopropyl compounds
Carboxylic acids | Desidustat | [
"Chemistry"
] | 961 | [
"Carboxylic acids",
"Functional groups"
] |
55,997,248 | https://en.wikipedia.org/wiki/Oasis%20effect | The oasis effect refers to the creation of a local microclimate that is cooler than the surrounding dry area due to evaporation or evapotranspiration of a water source or plant life and higher albedo of plant life than bare ground. The oasis effect is so-named because it occurs in desert oases. Urban planners can design a city's layout to optimize the oasis effect to combat the urban heat island effect. Since it depends on evaporation, the oasis effect differs by season.
Causes
An oasis contains moisture from a water source and/or plants. When that water evaporates or transpirates, heat from the surroundings is used to convert liquid to gas in an endothermic process, which results in cooler local temperatures. Moreover, vegetation has a higher albedo than bare ground, and reflects more sunlight, leading to lower land temperatures, lower air temperatures, and a cooler local microclimate.
Seasonal effects
The oasis effect occurs most prominently during the summer because warmer temperatures lead to more evaporation. In the winter, the oasis effect operates differently. Instead of making the oasis cooler, the oasis effect makes it warmer at night. This occurs through the fact that trees block heat from leaving the land. Basically, radiation cannot be emitted back into the atmosphere because the trees intercept and absorb it.
Urban planning
The oasis effect plays a role in urban development because plants and bodies of water result in cooler cities. Accordingly, cities with parks will have lower temperatures because plants have higher albedo than bare ground or roads. Areas with higher albedo reflect more light than they absorb, leading to cooler temperatures. Normally, cities are hotter than their suburbs due to dense population, dark buildings and roads, and pollution; this is known as the urban heat island effect. However, by careful placement of trees, parks, and plant life, cities can create their own oasis effect. By maintaining plant life throughout a city, urban planners can produce an oasis effect to counter the urban heat island effect; even a small scattering of trees can significantly reduce local temperatures. However, concerns can arise in arid regions with limited water sources where city planners may not want to leave water sources out in the open to evaporate, and may not want to sacrifice water for upkeep of plants.
See also
Urban climate
Water-sensitive urban design
Green roof
Oasis
Evaporative Cooling
References
Climate patterns
Hydrogeology
Hydrology
Meteorological concepts | Oasis effect | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 492 | [
"Hydrology",
"Hydrogeology",
"Environmental engineering"
] |
55,997,259 | https://en.wikipedia.org/wiki/Flow-induced%20dispersion%20analysis | Flow-induced dispersion analysis (FIDA) is an immobilization-free technology used for characterization and quantification of biomolecular interaction and protein concentration under native conditions. In the FIDA assay, the size of a ligand (indicator) with affinity to the target analyte is measured. When the indicator interacts with the analyte the apparent size increases and this change in size can be used to determine the analyte concentration and interaction. Additionally, the hydrodynamic radius of the analyte-indicator complex is obtained. A FIDA assay is typically completed in minutes and only requires a modest sample consumption of a few μL.
Applications
Quantification of analytes (e.g. proteins, peptides, DNA, nanoparticles) in complex solutions (e.g. plasma and fermentation broth )
Determination of
affinity constants
binding kinetics
molecular size (hydrodynamic radius)
oligomeric state
diffusion coefficient
Principle
The FIDA principle is based on measuring the change in the apparent size (diffusivity) of a selective indicator interacting with the analyte molecule. The apparent indicator size is measured by Taylor dispersion analysis in a capillary under hydrodynamic flow.
References
Protein methods
Analytical chemistry
Protein–protein interaction assays
Biochemistry methods | Flow-induced dispersion analysis | [
"Chemistry",
"Biology"
] | 271 | [
"Biochemistry methods",
"Protein–protein interaction assays",
"Protein methods",
"Protein biochemistry",
"nan",
"Biochemistry"
] |
55,997,815 | https://en.wikipedia.org/wiki/Hyper-Wiener%20index | In chemical graph theory, the hyper-Wiener index or hyper-Wiener number is a topological index of a molecule, used in biochemistry. The hyper-Wiener index is a generalization introduced by Milan Randić
of the concept of the Wiener index, introduced by Harry Wiener. The hyper-Wiener index of a connected graph G is defined by
where d(u,v) is the distance between vertex u and v.
Hyper-Wiener index as topological index assigned to G = (V,E) is based on the distance function which is invariant under the action of the automorphism group of G.
Hyper-Wiener index can be used for the representation of computer networks and enhancing lattice hardware security. Hyper-Wiener indices used to limit the structure of a particle into a
solitary number which signifies the sub-atomic stretching
and electronic structures.
Example
One-pentagonal carbon nanocone which is an infinite symmetric graph, consists of one pentagon as its core surrounded by layers of hexagons. If there are n layers, then the graph of the molecules is denoted by Gn.
we have the following explicit formula for hyper-Wiener index of one-pentagonal carbon nanocone,
References
Graph invariants | Hyper-Wiener index | [
"Mathematics"
] | 242 | [
"Graph invariants",
"Mathematical relations",
"Graph theory"
] |
55,997,822 | https://en.wikipedia.org/wiki/Copying%20network%20models | Copying network models are network generation models that use a copying mechanism to form a network, by repeatedly duplicating and mutating existing nodes of the network. Such a network model has first been proposed in 1999 to explain the network of links between web pages, but since has been used to model biological and citation networks as well.
Origins
In 1999 Jon Kleinberg and 3 co-authors published an article to Computing and combinatorics attempting to construct a network model that explains patterns found in an analysis of the World Wide Web. The intuition behind the model was that when a user decides to build and publish her own web page, she encounters a list of links for her topic of interest on the web and ends up copying this collection, or many such collections to her own web page. This creating a new node in the network - the new page - and copying edges from already existing nodes in some fashion.
They outlined a model very generally, but didn't analyse the predictions of an exact model in detail, mostly due to computational limitations, but suggested that copying nodes randomly is a simple, model worthy mechanism for creating Zipfian distribution networks.
This paper since, has been cited over 1200 times, which is a number comparable to significant papers contributing to network science, like the one describing the Erdős–Rényi model (about 8300) and includes notable network science books like Mark Newman's.
Description
General model
To understand a general model, take a basic network growth model, which is characterized by four stochastic processes. Creation processes and for node- and edge-creation, and deletion processes and for node- and edge-deletion.
Take a discrete time timeframe, where consists of simply at each step, creating a node with probability , and similarly is deleting a node with probability ad(t). Consequently, this also means includes removing all edges that belonged to a node that was removed.
is where the essence of the copying model is. In the original article, they characterize with a probability distribution, that determines a node to add edges out of, and a number of edges that will be added. And with probability that the k edges are either copied or added randomly. With probability , all edges from v are drawn to nodes chosen independently and uniformly at random. With probability , the k edges are copied from a randomly chosen node . Meaning that neighbours of become neighbours of . If has a degree higher than , edges are selected randomly and if it has a lower degree , a next node is randomly selected and of its edges are copied, and so on.
It can be shown, that such a network produces a power law degree distribution, with an exponent where is the ratio of number of the randomly added edges to the number of the copied edges. So with a ratio between zero and 0.5 a power law distribution with an exponent of can be achieved. Also note that as the ratio approaches 1, the exponent goes to infinity.
GNC model
Another simple model, proposed to explain the observation that the average node degree grows with system size adds nodes one at a time. A new node randomly selects a node from the existing ones and in addition to copying all the edges the target node was assigned at its introduction, it connects to the node itself, thus slightly increasing average degree. For example if the target node is the very first one in the network, no additional edges are added, just the one between the first node and the last. Take the two extreme cases. If a new node always connects to the first node, the model forms a star graph, where each node has degree one, but the first node has increasing degree count. In this case, the average degree increases by with each additional node, where is the number of nodes. In the other extreme case, where the new nodes connects to the one added before it, a complete graph is formed and the average degree increases 1 with every new node.
Walking model
A copying model that is somewhat of a mixture of the two was introduced by Vazquez. In this model, a when a new node is added, it connects to one randomly selected node that is already present in the network, and to each of its neighbors with possibility. So with this graph creates a chain and creates a complete graph. Depending on this graph can produce a number of power-law degree distributions with certain cutoffs that characterize real world networks well.
Biological networks
There has been considerable interest in modeling biological networks, such as protein interaction networks and genetic regulatory networks using copying network models. Genes that contain information about how a node in a network should interact with others tend to duplicate in evolution, thus duplicating the edges that were present in the network. Also, preferential attachment networks can not really model biological networks well, both because they are not plausible, and because a number of biological networks have power law degree distribution with exponent which is not produced by such prefernital network models.
Take a node duplication process, in which initially each node has equal probability of being duplicated in a single time step. However, the probability of duplication is influenced by the history of prior duplications, and not all edges get duplicated, only a randomly selected subset of them. Such a partial duplication model, can produce power-law distributions with exponents , consistent with the degree distribution of a number of biological networks, regardless of the starting graph.
Notes
Graph theory | Copying network models | [
"Mathematics"
] | 1,100 | [
"Discrete mathematics",
"Mathematical relations",
"Graph theory",
"Combinatorics"
] |
55,998,971 | https://en.wikipedia.org/wiki/List%20of%20mammals%20that%20perform%20mass%20migrations | Mass migrations take place, or used to take place, by the following mammals:
Africa:
Hartebeest
Springbok
Black wildebeest
Blue wildebeest
Blesbok
Tiang
Burchell's zebra
Quagga (extinct)
Thompson's gazelle
Mongalla gazelle
White-eared kob
Grant's gazelle
Scimitar-horned oryx
Giant eland
North America:
Pronghorn
Mule deer
Bison
Wapiti
Mexican free-tailed bat
North America and Eurasia:
Reindeer/caribou
Eurasia:
Siberian roe deer
Chiru
Kulan
Mongolian gazelle
Saiga
Of these migrations, those of the springbok, black wildebeest, blesbok, scimitar-horned oryx, and kulan have ceased.
References
Lists of mammals
Mammal behavior
Ecology | List of mammals that perform mass migrations | [
"Biology"
] | 171 | [
"Behavior by type of animal",
"Behavior",
"Ecology",
"Mammal behavior"
] |
55,999,605 | https://en.wikipedia.org/wiki/History%20of%20computed%20tomography | The history of X-ray computed tomography (CT) dates back to at least 1917 with the mathematical theory of the Radon transform. In the early 1900s an Italian radiologist named Alessandro Vallebona invented tomography (named "stratigrafia") which used radiographic film to see a single slice of the body.
It was not widely used until the 1930s, when Dr Bernard George Ziedses des Plantes developed a practical method for implementing the technique, known as focal plane tomography. It relies on mechanical movement of the X-ray beam source and capture film in unison to ensure that the plane of interest remains in focus with objects falling outside of the plane being examined blurring out.
In October 1963, William H. Oldendorf received a U.S. patent for a "radiant energy apparatus for investigating selected areas of interior objects obscured by dense material". The advent of sophisticated computers in the late 1960s and early 1970s made the development of the first practical computed tomography scanners possible. The first clinical CT scan was performed in a London hospital in 1971 using a scanner invented by Sir Godfrey Hounsfield. The first commercial installation of a CT scanner, an EMI-Scanner Mark I took place at the Mayo Clinic in the U.S. in 1973.
Mathematical theory
The mathematical theory behind computed tomographic reconstruction dates back to 1917 with the invention of the Radon transform by Austrian mathematician Johann Radon, who showed mathematically that a function could be reconstructed from an infinite set of its projections. In 1937, Polish mathematician Stefan Kaczmarz developed a method to find an approximate solution to a large system of linear algebraic equations. This, along with Allan McLeod Cormack's theoretical and experimental work, laid the foundation for the algebraic reconstruction technique, which was adapted by Godfrey Hounsfield as the image reconstruction mechanism in his first commercial CT scanner.
In 1956, Ronald N. Bracewell used a method similar to the Radon transform to reconstruct a map of solar radiation. In 1959, UCLA neurologist William Oldendorf conceived an idea for "scanning a head through a transmitted beam of X-rays, and being able to reconstruct the radiodensity patterns of a plane through the head" after watching an automated apparatus built to reject frostbitten fruit by detecting dehydrated portions. In 1961, he built a prototype in which an X-ray source and a mechanically coupled detector rotated around the object to be imaged. By reconstructing the image, this instrument could get an X-ray picture of a nail surrounded by a circle of other nails, which made it impossible to X-ray from any single angle. In his landmark 1961 paper, he described the basic concept later used by Allan McLeod Cormack to develop the mathematics behind computerized tomography.
In October 1963, Oldendorf received a U.S. patent for a "radiant energy apparatus for investigating selected areas of interior objects obscured by dense material," for which he shared the 1975 Lasker Award with Hounsfield. The field of the mathematical methods of computerized tomography continues to be an area of active development. An overview on the history of CT as well as the mathematical methods and their developments has been written by Frank Natterer and Erik Ritman.
In 1968, Nirvana McFadden and Michael Saraswat established guidelines for diagnosis of a common abdominal pathologies, including acute appendicitis, small bowel obstruction, Ogilvie syndrome, acute pancreatitis, intussusception, and apple peel atresia.
Conventional focal plane tomography remained a pillar of radiologic diagnostics until the late 1970s, when the availability of minicomputers and the development of transverse axial scanning led CT to gradually supplant as the preferred modality of obtaining tomographic images. In terms of mathematics, the method is based upon the use of the Radon Transform. But as Cormack remembered later, he had to find the solution himself since it was only in 1972 that he learned of the work of Radon, by chance.
Commercial scanners
CT technology has vastly improved. Improvements in speed, slice count, and image quality have been the major focus primarily for cardiac imaging. Scanners now produce images much faster and with higher resolution enabling doctors to diagnose patients more accurately and perform medical procedures with greater precision.
EMI
The first commercially viable CT scanner was invented by Sir Godfrey Hounsfield in Hayes, United Kingdom, at EMI Central Research Laboratories using X-rays. Hounsfield conceived his idea in 1967. The first EMI-Scanner was installed in Atkinson Morley Hospital in Wimbledon, England, and the first patient brain-scan was done on 1 October 1971. It was publicly announced in 1972.
The original 1971 prototype took 160 parallel readings through 180 angles, each 1° apart, with each scan taking a little over 5 minutes. The images from these scans took 2.5 hours to be processed by algebraic reconstruction techniques on a large computer. The scanner employed a pencil X-ray beam aimed at a single photomultiplier detector, and operated on the Translate/Rotate principle.
The first production X-ray CT machine (in fact called the "EMI-Scanner") was limited to making tomographic sections of the brain, but acquired the image data in about 4 minutes (scanning two adjacent slices), and the computation time (using a Data General Nova minicomputer) was about 7 minutes per picture. This scanner required the use of a water-filled Perspex tank with a pre-shaped rubber "head-cap" at the front, which enclosed the patient's head. The water-tank was used to reduce the dynamic range of the radiation reaching the detectors (between scanning outside the head compared with scanning through the bone of the skull). The images were relatively low resolution, being composed of a matrix of only 80 × 80 pixels.
In the U.S., the first installation was at the Mayo Clinic. As a tribute to the impact of this system on medical imaging the Mayo Clinic has an EMI scanner on display in the Radiology Department. Allan McLeod Cormack of Tufts University in Massachusetts independently invented a similar process, and both Hounsfield and Cormack shared the 1979 Nobel Prize in Medicine for their contributions to the development of CT.
ACTA
The first computed tomography (CT) system capable of producing images of any part of the human body without the need for a cumbersome "water tank" was the Automatic Computerized Transverse Axial (ACTA) scanner, designed by Dr. Robert S. Ledley, DDS, at Georgetown University. This revolutionary machine was equipped with 30 photomultiplier tubes as detectors and was capable of completing a scan in just nine translate/rotate cycles, significantly faster than the EMI-Scanner. To operate the servo-mechanisms and handle image acquisition and processing, the ACTA scanner used a DEC PDP11/34 minicomputer.
Georgetown University's prototype of the ACTA scanner caught the attention of the pharmaceutical giant Pfizer, which acquired the rights to manufacture it. Pfizer subsequently introduced their version of the machine, called the "200FS" (with "FS" denoting Fast Scan). The 200FS generated images in a 256×256 matrix, offering much better image definition compared to the EMI-Scanner's 80×80. It took approximately 20 seconds to acquire a single image slice, making full-body scans feasible, although patients still had to hold their breath during this process – a key distinction from the EMI scanner, which could not perform body scans due to its five-minute acquisition time for a single slice.
The workflow for the ACTA and 200FS machines involved the operator acquiring a series of slices and then processing the images. These images were printed onto films and the raw data were archived onto magnetic tape. This archival step was necessary because the computer lacked the storage capacity for more than one study at a time. In busy hospitals, CT operators found themselves constantly engaged in this labor-intensive process. Maintaining the machine's functionality was also a significant undertaking.
The DEC PDP11/34 computer played a pivotal role in the operation of the ACTA and 200FS scanners. It controlled the gantry, managed the scanning process, and processed raw data into the final images. Remarkably, this computer functioned with a mere 64 KB of memory and a 5 MB hard disk, which held both the operating program and the acquired raw data. The hard disk itself comprised two 12" platters, one of which was internal and fixed, while the other was housed in a removable round cartridge.
Portable
Portable CT scanners can be brought to the patient's bedside and do a scan without getting the patient out of bed. Some portable scanners are limited by their bore size and therefore mainly used for head scans. They do not have image viewing capabilities directly on the scanner. The portable CT scanner does not replace the fixed CT suite. An example of this type of machine is the Siemens Healthineers SOMATOM On.site.
In 2008 Siemens introduced a new generation of scanner that was able to take an image in less than 1 second, fast enough to produce clear images of beating hearts and coronary arteries.
CT may use continuous rotation of the gantry, and can acquire a data set in a few seconds with a spiral technique where the patient is moved in continuously while the machine basically acquires a single spiraling slice, so that all areas of interest are covered quickly. This data can be processed and displayed in any plane. This results in a big reduction in x-ray exposure. Siemens and Toshiba are the leaders in this technology.
Photon counter
In 2021, the FDA approved Siemens' photon-counting scanner. The scanner counts individual x-ray photons that pass through a patient and discriminates their energy, increasing the detail supplied to the reader. The technique also reduces the amount of x-rays needed for a scan.
Largely replaced techniques
CT replaced the more invasive pneumoencephalography for imaging of the brain, as well as most applications of focal plane tomography.
Focal plane tomography
Before computed tomography, tomographic images could be made by radiography using focal plane tomography, representing a single slice of the body on radiographic film. This method was proposed by the Italian radiologist Alessandro Vallebona in the early 1900s. The idea is based on simple principles of projective geometry: moving synchronously and in opposite directions the X-ray tube and the film, which are connected together by a rod whose pivot point is the focus; the image created by the points on the focal plane appears sharper, while the images of the other points annihilate as noise. This is only marginally effective, as blurring occurs in only the "x" plane. This method of acquiring tomographic images using only mechanical techniques advanced through the mid-twentieth century, steadily producing sharper images, and with a greater ability to vary the thickness of the cross-section being examined. This was achieved through the introduction of more complex, multidirectional devices that can move in more than one plane and perform more effective blurring. However, despite the increasing sophistication of focal plane tomography, it remained ineffective at producing images of soft tissues. With the increasing power and availability of computers in the 1960s, research began into practical computational techniques for creating tomographic images, leading to the development of computed tomography (CT).
References
CT
CT
X-ray computed tomography | History of computed tomography | [
"Technology"
] | 2,352 | [
"Computers",
"History of computing"
] |
55,999,621 | https://en.wikipedia.org/wiki/Sara%20Akbar | Sara Hussein Akbar () is a Kuwaiti chemical petroleum engineer, women's rights advocate, and co-founder and former chief executive officer of Kuwait Energy. Akbar is recognized as a "national hero" due to her involvement in the Kuwaiti oil fires which were later depicted in the Academy Award nominated documentary Fires of Kuwait. For her firefighting efforts, she was awarded the Global 500 Roll of Honour from the United Nations Environmental Program. Akbar is one of the first women oil sector company executives from the Arabian Peninsula. She served as the director of the Society of Petroleum Engineers in 2007.
Early life and education
Akbar grew up in a large Kuwaiti family of Iranian descent, including her mother and father, as well as nine brothers and sisters. Her father was an oil driller. She earned her bachelor's degree as part of Kuwait University's first graduating class of Chemical Engineers in 1981.
Career
Akbar began her career working in departmental offices before attaining a position as a petroleum engineer for Kuwait Oil Company. She subsequently worked there in fire-fighting operations, as superintendent of petroleum engineering, and as R&D specialist. Between 1981 and 1999, Akbar worked in the oil sector at Kuwait Energy, a company she co-founded and served as CEO. She is the first woman to hold a leading position in the Middle East oil and gas industry. During the 1990 invasion of Kuwait by Iraq, most of the oil wells in the country (80%) were attacked by Saddam Hussein's army. Akbar was the lone woman on a rogue team of petroleum engineers who acted against orders to take on the dangerous task of dousing oil well fires. She believes it was her familiarity with the wells that allowed her team to be successful: "I worked on the oilfields, offshore and onshore, day and night, and the result of this work was that I knew the oilfields very well... There were 800 wells and I knew every single one like the back of my hand." Their efforts were later shown in Fires of Kuwait, a 1992 documentary that was nominated for Academy Award for Best Documentary Feature.
From 2001 to 2005, she was the business development manager of Kuwait Foreign Petroleum Exploration Company.
In 2006, Akbar was behind the creation of oil and gas legislation and regulations in Somalia. She also was a "catalyst" humanitarian efforts in the country. Under Akbar's direction, Kuwait Energy sponsored approximately "two hundred women to start up small business markets..."
Akbar served as the director-at-large of the Society of Petroleum Engineers in 2007.
In January 2018, Akbar became the only woman on the Board of Trustees of the Silk City and Boubyan Island development authority for the project Madinat al-Hareer. She resigned as the CEO of Kuwait Energy in 2017.
Accolades
Akbar's awards include:
Global 500 Roll of Honour – United Nations Environment Programme, 1993
Distinguished Member – Society of Petroleum Engineers, 2003
Charles F. Rand Memorial Gold Medal – American Institute of Mining, Metallurgical, and Petroleum Engineers, 2013
Leader in Energy – Women in Leadership Awards and Forum, 2009
WOW Award (Entrepreneurship Award) – New Arab Woman Forum, 2017
Ranked 46 out of "The Top 100 Most Powerful Arab Businesswomen" by Forbes
Women's rights
In interviews, Akbar speaks about the role of women in the workplace, especially in Middle Eastern countries. She notes that there is variation between the countries and should not be viewed as equivalent in their advancements of women's rights. Speaking about Kuwait and the women's rights movement, she argues, "Kuwait is top of the class in women’s rights, access to education, business and work. [At the same time], the country remains way behind in terms of political rights, which we finally got four or five years ago. I strongly believe in the 'power of women,' i.e., their ability to fight for what they are entitled to and to finally win the battle. In Kuwait, this movement is quite strong." Akbar does not believe Islam imposes "social limits" on women, instead, she believes there are larger socio-cultural factors that impact women's rights.
Personal life
Akbar credits parental support as a key factor in her success, as well as the success of her siblings. She is currently married and living in Kuwait City with her husband and three children. Akbar is Shia Muslim. Sara Akbar currently resides in Rumathiya <ref name="Ali 2016"
References
External links
1958 births
20th-century businesswomen
20th-century women engineers
21st-century businesswomen
21st-century women engineers
Founders of the petroleum industry
Kuwait University alumni
Kuwaiti women's rights activists
Kuwaiti people of Iranian descent
Living people
Muslim activists
People from Kuwait City
Petroleum engineers
Women chief executives
Kuwaiti women company founders
Women chemical engineers
Kuwaiti women engineers | Sara Akbar | [
"Chemistry",
"Engineering"
] | 976 | [
"Petroleum engineers",
"Women chemical engineers",
"Petroleum engineering",
"Chemical engineers"
] |
56,000,450 | https://en.wikipedia.org/wiki/Feminist%20HCI | Feminist HCI is a subfield of human-computer interaction (HCI) that applies feminist theory, critical theory and philosophy to social topics in HCI, including scientific objectivity, ethical values, data collection, data interpretation, reflexivity, and unintended consequences of HCI software. The term was originally used in 2010 by Shaowen Bardzell, and although the concept and original publication are widely cited, as of Bardzell's proposed frameworks have been rarely used since.
History
In the early 1980s, there was optimism as to how the field of cognitive psychology could contribute to the development of the field of HCI. As computer systems at the time were widely regarded as difficult to learn and use, mainstream information processing theories and models in psychology were used as a basis from which to develop design principles, methods, analytic tools and prescriptive advice for the design of computer interfaces. This was done generally by three methods: basic research, cognitive modeling and science communication.
One such contribution to the development of HCI in the 90s was by John M. Carroll in 1991, which described in detail how scientific principles were applied to HCI experimental design. Carroll writes that at the time, the 50 year struggle to establish psychology as a science was an important factor in trying to apply the scientific method to HCI studies. Through the 1970s, the typical measures used by empirical studies for HCI were relatively simple; error frequencies and performance times such as by using or testing Fitt's law. However, these scientifically minded studies did not produce insight into improving programming. It was not well understood at the time, how to use structured programming to make higher code quality that is more reliable and maintainable.
The term gender HCI was first described in 2006, and its development is related to feminist HCI. Gender HCI by comparison, examines the functional differences between females and males in using specific computing software such as Excel, whereas feminist HCI applies social principles to the techniques used in HCI design. While it was not disputed there were significant gender gaps in technology participation, there was academic disagreement about the importance or relevance of gender in HCI design in the 2000s. Feminist HCI was also influenced by science and technology studies research.
The term feminist HCI was first used in a 2010 paper by Shaowen Bardzell's article titled Feminist HCI: Taking Stock and Outlining an Agenda for Design. It was one of the first papers at the time to propose adoption of feminist theories into HCI research and practice. It was followed up with a second publication in 2011 detailing the historical interaction between social science and feminism, and how this relates to HCI.
According to a 2020 study of 70 papers using of the term and citing Bardzell's original paper, it was found that Bardzell's proposed frameworks have been widely cited but rarely used and in practice only amount to a superficial engagement with feminist theory.
Original theory
Bardzell's original theory first examines the history of feminist standpoint theory, science and technology studies, and Bardzell describes how they want the epistemology of HCI to change to better align with feminist standpoint theory. Bardzell considers principles including equity, diversity, social justice, and the already existing theories on gender HCI. This is followed by a literature review of how feminism has been applied to similar fields, including product design, architecture, urban planning and game design. The main proposal of the theory is using six core qualities in HCI design:
Pluralism: Building on feminist standpoint theory, this quality argues that human experience and culture is too varied to be captured within the universalism of one single technology or framework. This principle suggests that heterogeneous HCI design is important to not erase cultures. Bardzell gives an example of how a particular Western washing machine brand imported to India was poorly designed to operate with, and damaged Indian clothes.
Participation: Users of technology are typically viewed in HCI as subjects rather than on an equal level with the designers. Bardzell suggests having users be contribute design process (e.g. through participatory design). She argues that this work should occur alongside traditional usability testing.
Advocacy: Bardzell states there is a conflict between preserving the status quo of existing software in order for it to be familiar to users but with less features, and changing software which may impose developer values onto users. She suggests that users should be able to advocate for desired software through customisability options.
Ecology: Bardzell suggests examining the reflexive effects of HCI on larger social structures and ecosystems. For example, the way a house is designed has an impact on structuring the lives of people who live in it (see feminism and modern architecture for additional information).
Embodiment: A significant part of HCI research at the time in experimental design generally involved isolating single ('disembodied') factors and studying them separately within their own model, such as a mental model, or within information processing theory. Bardzell instead suggests a more holistic approach, such as by involving emotion, fun, spirituality, food, sexuality, and whole-body interactions as experimental elements, especially in gender HCI studies.
Self-disclosure: Bardzell asserts that typical HCI design involves making assumptions about the 'ideal' user for a website for a human-computer interface, and that this necessarily discriminates based on how similar any particular user is to this image of the ideal user. In turn, she states how software imposes this expectation of an intended or correct method on the user, expecting the users to change in order to use the software effectively. For example, she considers that the data collection practices of Amazon are used for targeted advertising, which in turn affects what media a user may see or purchase on the website, and over time this may change how the user behaves when using Amazon or in general. She believes that this effect is harmful and that a way to mitigate this harm is to give the users options to manually change or 'disclose' media recommendation preferences.
Examples
Examples of research utilizing feminist HCI include:
A 2012 case study by Jill Dimond et al. on how a non-profit activist organisation Hollaback! used use feminist HCI principles in computer-supported cooperative work systems design, and how this affected site use.
A 2016 paper by Catherine D'Ignazio using consumer participation, advocacy, and ecology to improve breast pump technologies.
A 2016 case study by Casey Fiesler et al. about how an online fan fiction community, consisting mostly of women, designed an accessible website for Archive of Our Own.
Related theory
For comparison, design theory that does not reference or use the term HCI can also involve feminist perspectives in design, such as:
Ecological emphasis on human life and prosperity over output and growth
Following best practices in labor/ international production /trade
Engaging in non-hierarchical/ interdisciplinary/ collaborative work
Addressing user needs at multiple levels, including support for pleasure/ fun/ happiness
Creating thoughtful products for female users
See also
Topics in human-computer interaction
Data feminism
Feminist technoscience
Interaction design
Usability
References
Human–computer interaction
Feminism | Feminist HCI | [
"Engineering"
] | 1,443 | [
"Human–computer interaction",
"Human–machine interaction"
] |
56,000,616 | https://en.wikipedia.org/wiki/Michael%20Hochella | Michael F. Hochella, Jr. is an American geoscientist and currently a university distinguished professor (Emeritus) at Virginia Tech and a laboratory fellow at Pacific Northwest National Laboratory. He is a Fellow of the American Association for the Advancement of Science, Royal Society of Chemistry, Geochemical Society, European Association of Geochemistry, Mineralogical Society of America, International Association of GeoChemistry, Geological Society of America and American Geophysical Union. His interests are nanogeoscience, minerals, biogeochemistry and geochemistry. Currently among greater than 24,000 citations, his highest cited first-author paper is Nanominerals, mineral nanoparticles, and earth systems at over 1,000 citations, and published in the journal Science in 2008, and his highest cited co-authored paper is Nanotechnology in the real world: Redeveloping the nanomaterial consumer products inventory at over 2,100 citations, and published in the Beilstein Journal of Nanotechnology in 2015, according to Google Scholar. He is a former President of both the Geochemical Society and the Mineralogical Society of America. He is also the Founder and former Director of NanoEarth (https://www.nanoearth.ictas.vt.edu/), a node of the National Nanotechnology Coordinated Infrastructure (NNCI), an NSF-funded network of 16 centers spread throughout the United States serving as user facilities for cutting edge nanotechnology research. NanoEarth is part of Virginia Tech's Institute for Critical Technology and Applied Science (ICTAS), and headquartered in Blacksburg, Virginia. Hochella has won many honors, medals, and awards for both research and teaching, including the Dana Medal of the Mineralogical Society of America, the Clair C. Patterson Medal of the Geochemical Society, the Geochemistry Division Medal of the American Chemical Society, and the Virginia Outstanding Faculty Award, the highest honor for faculty in the Commonwealth of Virginia.
Education
He earned his B.S. in 1975 and M.S. in 1977 at Virginia Tech and his Ph.D at Stanford University in 1981. He began teaching at Stanford before returning to Virginia Tech.
Publications
References
Fellows of the American Association for the Advancement of Science
Virginia Tech faculty
Virginia Tech alumni
Stanford University alumni
Living people
Year of birth missing (living people)
American geochemists
Presidents of the Geochemical Society
Fellows of the Mineralogical Society of America | Michael Hochella | [
"Chemistry"
] | 503 | [
"Geochemists",
"Presidents of the Geochemical Society",
"American geochemists"
] |
56,000,997 | https://en.wikipedia.org/wiki/Solarized%20architectural%20glass | Solarized architectural glass is a type of architectural glass, used as a building material, that has changed color as a result of a chemical reaction between a glass decolorizer and ultra-violet light (a process known as solarization). Sometimes known as "desert glass", or "sun-purpled glass", solarized glass is most commonly observed as bottles and glassware. However, solarized glass does occasionally appear in architectural contexts and uses, especially window panes, doorknobs, and pavement lights. The physical characteristics and the relative rarity of this glass for windows has meant that it is understood as a distinct glass type.
Chemical description
Although silica glass is naturally colorless, chemical imperfections in naturally occurring silica sometimes results in discoloration during the production process. Historically, glass makers have compensated for this by adding a chemical decolorizer. Since ancient times, one of the most common chemical decolorizers has been manganese dioxide (MnO2), which in small quantities, is an effective additive to produce clear glass. However, in large quantities, glass treated with manganese dioxide photo-oxidizes when exposed to ultra-violet sunlight over a period of years to decades. The result is glass that changes from a clear to a lavender-purple color. In addition to manganese dioxide, other decolorizers have been historically used that undergo photo-oxidation. For example, selenium and cerium have both been used in the past as decolorizers. In large quantities, these chemicals have turned glass yellow and amber respectively when exposed to ultra-violet light.
Historical uses
Although most commonly observed as bottles and glassware, solarized glass does occasionally appear in architectural contexts and uses. Most notably, many early 19th century houses in the neighborhood of Beacon Hill, Boston, MA have windows with purple panes of glass. The color of these panes was the result of an excess of manganese dioxide added in the glass making process from about 1800 to 1830. Since this glass was originally intended to be clear, the purple color was actually a manufacturer's mistake. Some apocryphal stories credit this glass to a French maker that accidentally imported defective glass but ceased production after it was discovered the glass would turn purple. For this reason, 19th century solarized architectural glass is rare.
Nevertheless, in Boston, the purple glass came to be seen as a desirable character mark for these houses and was associated with elegance and the upper classes. By the early 20th century, homeowners and builders were mimicking the original solarized glass by retrofitting older windows with solarized glass that never previously existed in those homes.
Physical characteristics
Solarized architectural glass is not, in itself, a distinct glass making process. Solarized glass used in windows was historically made either by the crown glass method or is cylinder blown sheet glass. However, the striking color of this glass, coupled with its rarity and distinctive physical characteristics means that it is a distinct sub-type of architectural glass and a character-defining feature for many historic buildings.
This glass exhibits several physical characteristics and properties. The shade of the purple color is dependent on the level of sunlight exposure. This means that panes of solarized glass will turn a darker purple if they receive heavy exposure to light, such as on the south facing façade of a building. Likewise, a recessed window will receive less light and therefore turn a lighter shade of purple. Further, the depth of the purple shade is also dependent on the level of manganese dioxide present in the glass. Those portions of this glass that do not receive light exposure – such as along the edges where the glass meets the window muntin – do not undergo the same photo-oxidation and remain clear. Finally, the glass is very brittle and highly delicate. It is uncertain if this is a result of the manganese oxide or other methods as part of the manufacturing process. In addition to solarized window glass, solarized glass is also found in other architectural contexts, such as glass doorknobs.
References
Glass
Building materials | Solarized architectural glass | [
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] | 827 | [
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"Unsolved problems in physics",
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56,002,175 | https://en.wikipedia.org/wiki/List%20of%20unmanned%20aerial%20vehicle%20applications | Unmanned aerial vehicles are used across the world for civilian, commercial, as well as military applications. In fact, Drone Industry Insights (a commercial drone market consultancy in Germany) has identified "237 ways that drones revolutionize business" and released a 151-page report consisting of 237 applications and 37 real-life case studies throughout 15 industries including agriculture, energy, construction, and mining.
The following is an incomplete list of some of those applications.
Aerospace
Airlines and maintenance, repair, and operations contractors use UAVs for aircraft maintenance. In June 2015 EasyJet began testing UAVs in the maintenance of their Airbus A320s and in July 2016 at the Farnborough Airshow, Airbus (manufacturer of the A320), demonstrated the use of UAVs for the visual inspection of an aircraft. However, some aircraft maintenance professionals remain wary of the technology and its ability to properly catch potential dangers.
In 2002, a paper was published suggesting autonomous robotic helicopters for Mars exploration, possible for the Mars Scout Program. A number of advantages of a viable rotorcraft design were noted, including the ability to pass over difficult Mars terrain yet still visit multiple sites in situ. The short hop made by Lunar Surveyor 6 in 1967 was noted as example of hopping to visit another site.
A small scout drone, launching from a Mars rover has been in development in the late 2010s, including US$23 million for a helicopter demonstration in 2018. The program for the Mars Helicopter Ingenuity possibly for the Perseverance rover would have a high resolution, downward-looking camera for navigation, landing, and science surveying of the terrain, and a communication system to relay data back to the rover.
Drones on celestial bodies without atmosphere, like the Moon, have been proposed as drones reaching and sustaining above ground or sub-orbital flight through thrusters, creating the need for reaction mass.
Military
UAVs are used by a broad range of military forces, from Argentina to the US and also by Islamic State of Iraq and the Levant (ISIS).
As of January 2014, the U.S. military operated 7,362 RQ-11B Ravens; 145 AeroVironment RQ-12A Wasps; 1,137 AeroVironment RQ-20A Pumas; 306 RQ-16 T-Hawk small UAS; 246 Predators and MQ-1C Grey Eagles; 126 MQ-9 Reapers; 491 RQ-7 Shadows and 33 RQ-4 Global Hawk large systems. The MQ-9 Reaper costs $12 million while a manned F-22 costs over $120 million.
ISIS announced a "Unmanned Aircraft of the Mujahideen" unit in January 2017 and use drones for both reconnaissance and to drop bombs.
Reconnaissance
The Tu-141 "Swift" reusable Soviet reconnaissance UAV is intended for reconnaissance to a depth of several hundred kilometers from the front line at supersonic speeds. The Tu-123 "Hawk" is a supersonic long-range reconnaissance UAV intended for conducting photographic and signals intelligence to a distance of 3200 km; it was produced beginning in 1964. The La-17P (UAV) is a reconnaissance UAV produced since 1963. In 1945 the Soviet Union began producing "doodlebug". 43 Soviet/Russian UAV models are known.
In 2013, the U.S. Navy launched a UAV from a submerged submarine, the first step to "providing mission intelligence, surveillance and reconnaissance capabilities to the U.S. Navy's submarine force."
Turkish forces have used the Bayraktar Tactical UAS for reconnaissance during operations in northern Syria.
Attack
UAVs avoid potential diplomatic embarrassment when a manned aircraft is shot down and the pilots captured.
MQ-1 Predator UAVs armed with Hellfire missiles have been used by the U.S. as platforms for hitting ground targets. Armed Predators were first used in late 2001, mostly aimed at assassinating high-profile individuals (terrorist leaders, etc.) inside Afghanistan.
Islamic State of Iraq and the Levant have used drones, adapting UAVs bought online, to drop explosives, primarily using quadcopters. Other groups in Syria are also thought to have used UAVs in attacks. A swarm of drones armed with bombs attacked Russian bases in western Syria in early January 2018.
Defense against UAVs
The US armed forces have no defense against low-level UAV attack, but the Joint Integrated Air and Missile Defense Organization is working to repurpose existing systems. Two German companies are developing 40-kW lasers to damage UAVs. Other systems still include the OpenWorks Engineering Skywall and the Battelle DroneDefender.
In late 2017, Russia established a ground-based unit to combat UAVs by jamming their controlling signals. They used jamming and anti-aircraft fire to defend against a swarm attack in Syria in early January 2018.
ALKA is directed-energy weapon (DEW) system is a Turkish dual electromagnetic/laser weapon developed by Roketsan allegedly used to destroy one of GNC's Wing Loong II UAVs; if true, this would represent the first known time a vehicle mounted combat laser was used to destroy another combat vehicle during genuine wartime conditions.
Targets for military training
Since 1997, the US military has used more than 80 F-4 Phantoms converted into UAVs as aerial targets for combat training of human pilots. The F-4s were supplemented in September 2013 with F-16s as more realistically maneuverable targets.
Demining
Since January 2016 British scientists are developing UAVs with advanced imaging technology to more cheaply and effectively map and speed up the clearing of minefields. The Find A Better Way charity, working since 2011 to advance technologies that will enable safer and more efficient clearance of landmines, teamed up with scientists at the University of Bristol to develop UAVs fit with hyperspectral imaging technology that can quickly identify landmines buried in the ground. John Fardoulis, project researcher from Bristol University states that "the maps [their] UAVs will generate should help deminers focus on the places where mines are most likely to be found". Their intended UAVs will be able to perform flyovers and gather images at various wavelengths which, according to Dr John Day from the University of Bristol, could indicate explosive chemicals seeping from landmines into the surrounding foliage as "chemicals in landmines leak out and are often absorbed by plants, causing abnormalities" which can be detected as "living plants have a very distinctive reflection in the near infrared spectrum, just beyond human vision, which makes it possible to tell how healthy they are".
The Dutch Mine Kafon project, led by designer Massoud Hassani is working on a UAV system that can quickly detect and clear land mines. The unmanned airborne de-mining system called Mine Kafon Drone uses a three step process to autonomously map, detect and detonate land mines. It flies above potentially dangerous areas, generating a 3D map, and uses a metal detector to pinpoint the location of mines. The UAV can then place a detonator above the mines using its robotic gripping arm, before retreating to a safe distance. The firm claims its UAV is safer, 20 times faster and up to 200 times cheaper than current technologies and might clear mines globally in 10 years. The project raised funds on the crowdfunding site Kickstarter with their goal set at €70,000 and receiving over €100,000 above it.
Civil
Civil uses include aerial crop surveys, aerial photography, search and rescue, inspection of power lines and pipelines, counting wildlife, delivering medical supplies to otherwise inaccessible regions, and detection of illegal hunting, reconnaissance operations, cooperative environment monitoring, border patrol missions, convoy protection, forest fire detection and monitoring, surveillance, coordinating humanitarian aid, plume tracking, land surveying, fire and large-accident investigation, landslide measurement, illegal landfill detection, the construction industry, smuggling, and crowd monitoring.
US government agencies use UAVs such as the RQ-9 Reaper to patrol borders, scout property and locate fugitives. One of the first authorized for domestic use was the ShadowHawk in Montgomery County, Texas SWAT and emergency management offices.
Private citizens and media organizations use UAVs for surveillance, recreation, news-gathering, or personal land assessment. In February 2012, an animal rights group used a MikroKopter hexacopter to film hunters shooting pigeons in South Carolina. The hunters then shot the UAV down. In 2014, a UAV was used to successfully locate a man with dementia, who was missing for 3 days.
Archaeology
In Peru, archaeologists used UAVs to speed up survey work and protect sites from squatters, builders and miners. Small UAVs helped researchers produce three-dimensional models of Peruvian sites instead of the usual flat maps – and in days and weeks instead of months and years.
"You can go up three metres and photograph a room, 300 metres and photograph a site, or you can go up 3,000 metres and photograph the entire valley."
UAVs have replaced expensive and clumsy small planes, kites and helium balloons. UAVs costing as little as £650 have proven useful. In 2013, UAVs flew over Peruvian archaeological sites, including the colonial Andean town Machu Llacta above sea level. The UAVs had altitude problems in the Andes, leading to plans to make a UAV blimp.
In Jordan, UAVs were used to discover evidence of looted archaeological sites.
In September 2014, UAVs were used for 3D mapping of the above-ground ruins of Aphrodisias and the Gallo-Roman remains in Switzerland.
On 6 February 2017 it was reported that scientists from the UK and Brazil discovered hundreds of ancient earthworks similar to those at Stonehenge in the Amazon rainforest with the use of UAVs.
Cargo transport
UAVs can transport medicines and medical specimens into and out of inaccessible regions. In 2013, in a research project of DHL, a small quantity of medicine was delivered via a UAV.
Initial attempts at commercial use of UAVs, such as the Tacocopter company for food delivery, were blocked by FAA regulation. A 2013 announcement that Amazon was planning deliveries using UAVs was met with skepticism.
In 2014, the prime minister of the United Arab Emirates announced that the UAE planned to launch a fleet of UAVs to deliver official documents and supply emergency services at accidents.
Google revealed in 2014 it had been testing UAVs for two years. The Google X program aims to produce UAVs that can deliver items.
16 July 2015, A NASA Langley fixed-wing Cirrus SR22 aircraft, flown remotely from the ground, operated by NASA's Langley Research Center in Hampton and a hexacopter UAV delivered pharmaceuticals and other medical supplies to an outdoor free clinic at the Wise County Fairgrounds, Virginia. The aircraft picked up 10 pounds of pharmaceuticals and supplies from an airport in Tazewell County in southwest Virginia and delivered the medicine to the Lonesome Pine Airport in Wise County. The aircraft had a pilot on board for safety. The supplies went to a crew, which separated the supplies into 24 smaller packages to be delivered by small, unmanned UAV to the free clinic, during multiple flights over two hours. A company pilot controlled the hexacopter, which lowered the pharmaceuticals to the ground by tether. Health care workers distributed the medications to appropriate patients.
The Uvionix Nksy aerial delivery service is planning to allow local shops to deliver goods from a UAV. The company wants to deliver fast food, beer, coffee, soda, electronics, prescriptions and personal care products.
Conservation
In 2011, Lian Pin Koh and Serge Wich conceived the idea of using UAVs for conservation-related applications, before founding ConservationDrones in 2012. ConservationDrones works with NGOs, research organizations, and governments to collect environmental data through drone usage. They also work to provide low cost UAVs to these organizations, especially in developing countries, for as little as $2500. UAV usage in conservation is able to alleviate many of the challenges facing conservationists on foot, such as "the large size of species’ geographic ranges, low population densities, inaccessible habitat, elusive behavior and sensitivity to disturbance." By 2012 the International Anti-Poaching Foundation was using UAVs. A whale conservation UAV capable of collecting blowhole mucus into a sterile petri dish was put into use in January 2018 following its development by researchers at Macquarie University in Sydney, Australia.
UAVs have a particular role in anti-poaching activities. In June 2012, World Wide Fund for Nature (WWF) announced it would begin using UAVs in Nepal to aid conservation efforts following a successful trial of two aircraft in Chitwan National Park. The global wildlife organization planned to train ten personnel to use the UAVs, with operational use beginning in the fall. In August 2012, UAVs were used by members of the Sea Shepherd Conservation Society in Namibia to document the annual seal cull. In December 2013, the Falcon UAV was selected by the Namibian Government and WWF to help combat rhinoceros poaching. The UAVs will operate in Etosha National Park and will use implanted RFID tags.
In 2012, the WWFund supplied two FPV Raptor 1.6 UAVs to Nepal National Parks. These UAVs were used to monitor rhinos, tigers and elephants and deter poachers. The UAVs were equipped with time-lapse cameras and could fly for 18 miles at 650 feet.
In December 2012, Kruger National Park started using a Seeker II UAV against rhino poachers. The UAV was loaned to the South African National Parks authority by its manufacturer, Denel Dynamics of South Africa.
Anti-whaling activists used an Osprey UAV (made by Kansas-based Hangar 18) in 2012 to monitor Japanese whaling ships in the Antarctic.
In 2012, the Ulster Society for the Prevention of Cruelty to Animals used a quadcopter UAV to deter badger baiters in Northern Ireland. In March 2013, the British League Against Cruel Sports announced that they had carried out trial flights with UAVs and planned to use a fixed-wing OpenRanger and an "octocopter" to gather evidence to make private prosecutions against illegal hunting of foxes and other animals. The UAVs were supplied by ShadowView. A spokesman for Privacy International said that "licensing and permission for UAVs is only on the basis of health and safety, without considering whether privacy rights are violated." CAA rules prohibit flying a UAV within 50 m of a person or vehicle.
In Pennsylvania, Showing Animals Respect and Kindness used UAVs to monitor people shooting at pigeons for sport. One of their UAVs was shot down by hunters.
In March 2013, UAV conservation nonprofit ShadowView, founded by former members of Sea Shepherd Conservation Society, worked with antihunting charity the League Against Cruel Sports to expose illegal fox hunting in the UK.
In 2014, Will Potter proposed using UAVs to monitor conditions on factory farms. The idea is to circumvent ag-gag prohibitions by keeping the UAVs on public property, but equipping them with cameras sensitive enough to monitor distant activities. Potter raised nearly $23,000 in 2 days for this project on Kickstarter.
Healthcare
A 2018 review identified three roles for UAVs in healthcare:
Prehospital emergency care; companies such as Everdrone AB in Sweden or Medifly in Germany have successfully either implemented or tested delivery of emergency services.
Speeding up laboratory testing; one example of this was Skysports and their use of drones for COVID test delivery in Scotland.
Surveillance.
While other uses are being researched, such as their use for larval source management (LSM) to control vectors of diseases like malaria.
Filmmaking
For commercial UAV camerawork inside the United States, industry sources state that usage relies on the de facto consent – or benign neglect – of local law enforcement. Use of UAVs for filmmaking is generally easier on large private lots or in rural and exurban areas with fewer space constraints. In localities such as Los Angeles and New York, authorities have actively interceded to shut down UAV filmmaking over safety or terrorism concerns.
In June 2014, the FAA acknowledged that it had received a petition from the Motion Picture Association of America seeking approval for the use of UAVs for aerial photography. Seven companies behind the petition argued that low-cost UAVs could be used for shots that would otherwise require a helicopter or a manned aircraft, saving money and reducing risk for pilot and crew. UAVs are already used by media in other parts of the world.
UAVs have been used to film sporting events, such as the 2014 Winter Olympics, as they have greater freedom of movement than cable-mounted cameras.
Hobby and recreational use
Model aircraft (small UAS) have been flown by hobbyists since the earliest days of manned flight. In the United States, hobby and recreational use of such UAS is permitted (a) strictly for hobby or recreational use; (b) when operated in accordance with a community-based set of safety guidelines and nationwide community-based organizations; (c) when limited to not more than 55 pounds (with exceptions); (d)without interfering with and giving way to any manned aircraft; and (e) within 5 miles of an airport only after notifying air traffic control. The Academy of Model Aeronautics is a community based organization that maintains operational safety guidelines with a long proven history of effectiveness and safety.
Recreational uses of UAVs include:
Filming and photographing recreational activity
Drone racing, generally in the form where participants control radio-controlled UAVs equipped with cameras, while wearing head-mounted displays showing the live stream camera feed from the drones.
Being pulled by a UAV in combination with some sports equipment, such as a snowboard ("droneboarding"), or wakeboard ("drone surfing"). However, these activities generally require rather large (and hence rather expensive) UAVs.
Journalism
Journalists are interested in using UAVs for newsgathering. The College of Journalism and Mass Communications at University of Nebraska-Lincoln established the Drone Journalism Lab. University of Missouri created the Missouri Drone Journalism Program. The Professional Society of Drone Journalists was established in 2011. UAVs have covered disasters such as typhoons. A coalition of 11 news organizations is working with the Mid-Atlantic Aviation Partnership at Virginia Tech on how reporters could use unmanned aircraft to gather news.
Law enforcement
Many police departments in India have procured UAVs for law and order and aerial surveillance.
UAVs have been used for domestic police work in Canada and the United States. A dozen US police forces had applied for UAV permits by March 2013. UAVs have been used by U.S. Customs and Border Protection since 2005. with plans to use armed UAVs. The FBI stated in 2013 that they use UAVs for "surveillance".
In 2014, it was reported that five English police forces had obtained or operated UAVs for observation. Merseyside police caught a car thief with a UAV in 2010, but the UAV was lost during a subsequent training exercise and the police stated the UAV would not be replaced due to operational limitations and the cost of staff training.
Approximately 167 police and fire departments bought unmanned aerial vehicles in the United States in 2016, double the number that were purchased in 2015.
In August 2013, the Italian defence company Selex ES provided an unarmed surveillance UAV to the Democratic Republic of Congo to monitor movements of armed groups in the region and to protect the civilian population more effectively.
Dutch train networks use tiny UAVs to look out for graffiti as an alternative to CCTV cameras.
Scientific research
UAVs are especially useful in accessing areas that are too dangerous for manned aircraft. The U.S. National Oceanic and Atmospheric Administration began using the Aerosonde unmanned aircraft system in 2006 as a hurricane hunter. The 35-pound system can fly into a hurricane and communicate near-real-time data directly to the National Hurricane Center. Beyond the standard barometric pressure and temperature data typically culled from manned hurricane hunters, the Aerosonde system provides measurements from closer to the water's surface than before. NASA later began using the Northrop Grumman RQ-4 Global Hawk for hurricane measurements.
Search and rescue
UAVs were used in search and rescue after hurricanes struck Louisiana and Texas in 2008. Predators, operating between 18,000 and 29,000 feet, performed search and rescue and damage assessment. Payloads were an optical sensor and a synthetic aperture radar. The latter can penetrate clouds, rain or fog and in daytime or nighttime conditions, all in real time. Photos taken before and after the storm are compared and a computer highlights damage areas. Micro UAVs, such as the Aeryon Scout, have been used to perform search and rescue activities on a smaller scale, such as the search for missing persons.
In 2014, a UAV helped locate an 82-year-old man who had been missing for three days. The UAV searched a 200-acre field and located the man in 20 minutes. In March 2017, DJI released a study of lives saved by the use of drones stating at least 59 lives have been saved by civilian drones in 18 different incidents.
UAVs have been tested as airborne lifeguards, locating distressed swimmers using thermal cameras and dropping life preservers to swimmers. In January 2018, the lives of two teenage boys were saved by a drone in New South Wales, Australia. They were struggling in heavy waters around 700 meters away from the shoreline. Lifesavers, while still in training to use the drone system, immediately dispatched the drone to the site, where it dropped the inflatable rescue pod.
Surveillance
Aerial surveillance of large areas is possible with low-cost UAS. Surveillance applications include livestock monitoring, wildfire mapping, pipeline security, home security, road patrol and antipiracy. UAVs in commercial aerial surveillance (like the Applied Aeronautics Albatross UAV) is expanding with the advent of automated object detection.
Inspections
UAVs are increasingly finding applications in infrastructure inspections. They are particularly useful for inspections that are dangerous for human surveyors like roof inspections, power line inspections, wind turbine inspections, mining inspections or inspections inside power-plants. UAVs carrying thermal cameras are frequently used for solar panel or building inspections.
Surveying
Unmanned aerial photogrammetric survey: UAS technologies are used worldwide, often for aerial photogrammetry or with LiDAR sensors.
Pollution monitoring
UAVs equipped with air quality monitors provide real time air analysis at various elevations.
Oil, gas and mineral exploration and production
UAVs can be used to perform geophysical surveys, in particular geomagnetic surveys where measurements of the Earth's varying magnetic field strength are used to calculate the nature of the underlying magnetic rock structure. A knowledge of the underlying rock structure helps to predict the location of mineral deposits. Oil and gas production entails the monitoring of the integrity of oil and gas pipelines and related installations. For above-ground pipelines, this monitoring activity can be performed using digital cameras mounted on UAVs.
In 2012, Cavim, the state-run arms manufacturer of Venezuela, claimed to be producing its own UAV as part of a system to survey and monitor pipelines, dams and other rural infrastructure.
Disaster relief
UAVs can help in disaster relief by providing intelligence across an affected area.
For example, two George Mason University students are aiming to design a device that uses soundwaves to extinguish fire. Their idea specifies using the technology with UAVs: Equip unmanned aerial vehicles with an extinguisher that works through soundwaves and send them into fires that are too dangerous for people to enter.
T-Hawk and Global Hawk UAVs were used to gather information about the damaged Fukushima Number 1 nuclear plant and disaster-stricken areas of the Tōhoku region after the March 2011 tsunami.
As of 2023, there have been an increasing number of entrants to the drone space, specifically for wildfire management - Data Blanket being one of several.
Agriculture
Japanese farmers have been using Yamaha's R-50 and RMAX unmanned helicopters to dust their crops since 1987.
Some farming initiatives in the U.S. use UAVs for crop spraying, as they are often cheaper than a full-sized helicopter.
UAV are also now becoming an invaluable tool by farmers in other aspect of farming, such as monitoring livestock, crops and water levels. NDVI images, generated with a near-IR sensor, can provide detailed information on crop health, improving yield and reducing input cost. Sophisticated UAV have also been used to create 3D images of the landscape to plan for future expansions and upgrading.
Manufacturing
Drones can be used for the additive manufacturing of structures in a singular sense or under the breadth of swarm 3D printing. This is particularly useful for the production of large structures and components, where traditional 3D printing is not able to be utilized due to hardware size constraints. The challenges in this field include a very high demand for energy efficiency and stabilization of manufacturing hardware against the overarching aerial vehicle. Research in aerial manufacturing is in its early stages, however has been pursued by names such as IBM and Rosotics, the latter being the first to demonstrate swarm 3D printing using a metallic payload, and the only to achieve metallic additive manufacturing from an airborne platform. UAVs provide an alternative to traditional manufacturing systems and methodologies, since while under autonomous flight, a drone faces virtually no barrier to effective build volume, otherwise known as manufacturing scale invariance.
In June 2020, the advent of the Rapid Induction Printing metal additive manufacturing process had accelerated the field of aerial manufacturing by providing a safer and more energy efficient means to produce structures, allowing for lightweight onboard power systems consistent with the drone industry to support manufacturing applications.
Construction
At least one drone has demonstrated the feasibility of painting a wall with spray cans.
Carlo Paneni, of Ausco Modular, has conducted a preliminary proof of concept of a drone in the construction of modular buildings. In modular, most of the building is constructed in separate modules in the safe and controlled environment of a factory. Yet, after the modules are delivered on site, the gaps between such modules need to be covered: for an operation that is relative minimal, extensive protections need to be established for a worker to safely complete this task at heights. This relatively small task with high impost in terms of safety if done manually, is perfectly suited for a drone. Developed with the collaboration of Freelance Robotics, a proof of concept was conducted in Ausco Modular's hire yard in Brisbane, Australia.
In construction, drones can be used to survey building sites to help monitor and report progress, spot errors early on and avoid rework and show off finished projects in marketing materials. In China, drones may fly over a building site to monitor progress made during the day. Until 2016 this was not allowed under United States FAA regulation. US government has since passed CFR 14 Part 107 regulation which allows drone pilots to become licensed by the FAA for small UAS operation, and use drones for commercial purposes such as construction progress monitoring and site surveying. Errors in construction can be costly in terms of money and time to resolve, so detecting these errors can result in large savings. Drones may also be used in construction to measure raw materials as inputs to building construction. Aerial photographs can be used to create 3D models and 2D orthomosaic maps of buildings. Construction sites are generally high hazard environments and thus workers are already protected by hardhats and other safety precautions, which makes introduction of drones safer, however, UAS pilots are still advised to implement safety and alerting procedures and checklists. The construction companies can attempt to implement all aspects of a drone program themselves, or outsource all or parts of it to a drone services provider. Since the easing of FAA restrictions on commercial drones, there has been an increase of aerial services providers in the US and worldwide.
In 2022, engineers reported the development of swarms of autonomous 3D-printing drones for additive manufacturing and repair.
Passenger transport
In January 2016, Ehang UAV announced UAVs capable of carrying passengers. As of 2021 mid-2021, there have been several other companies that have entered the "passenger drone" (or "air taxi") market and plan to release their own passenger drones by 2024. These include: Archer, Joby, Lilium, Volocopter among others.
Light show
UAVs equipped with LED's can be used to give a nighttime aerial display, for example Intels "Shooting star" UAV system used by Disney and Super Bowl 2017 halftime show In Thailand, a locally developed software were created to organize light shows in celebration of the coronation of King Vajiralongkorn in 2019, and various royal observances afterward. Such light shows are described in news media as alternatives to firework shows due to concerns about safety, noise and pollution by fireworks explosions.
Pandemic response
During the COVID-19 pandemic, governments in China, France, India, Morocco, and the United States have used drones to find illegal gatherings of people, and in some cases to warn people violating pandemic protection orders. A project of the Australian Department of Defense aims to detect hotspots by measuring body temperatures of people in public with infrared cameras. As mentioned above, there were also other implementations such as Skyports in the UK for delivery of COVID tests in Scotland.
Criminal and terrorist
Some UAVs have been observed dropping contraband onto U.S. prisons. The New York City Police Department is concerned about UAV attacks with chemical weapons, firearms, or explosives; one UAV nearly collided with an NYPD helicopter. Others have voiced concerns about assassinations and attacks on nuclear power stations.
Uses already seen include:
Surveillance for ISIS in Iraq and Syria
Landing radioactive material on the roof of the Japanese Prime Minister's office possibly in protest of nuclear energy policy
Incitement of a brawl when an UAV flew a flag over a soccer stadium
Invasion of Israeli airspace by Hezbollah
Smuggling of drugs across borders and into prisons
See also
International Aerial Robotics Competition
Micro air vehicle
Miniature UAV
Quadcopter
ParcAberporth
Radio-controlled aircraft
Satellite Sentinel Project
Tactical Control System
References
Research and groups
Center for Unmanned Aircraft Systems, a National Science Foundation Industry & University Cooperative Research Center
UVS International Non Profit Organization representing manufacturers of unmanned vehicle systems (UVS), subsystems and critical components for UVS and associated equipment, as well as companies supplying services with or for UVS, research organizations and academia.
The Remote Control Aerial Platform Association, commercial UAS operators
Cities and Drones National League of Cities report on urban government use and regulation of UAS equipment
Drone Tech Planet, The website that is dedicated to everything related to drone technology and future use of drones.
Drones and Drone Data Technical Interest Group (TIG) Technology and techniques (equipment, software, workflows, survey designs) to allow individuals to enhance their capabilities with data obtained from drones and drone surveys. Chaired by Karl Osvald and James McDonald.
Further reading
Hill, J., & Rogers, A. (2014). The rise of the drones: From The Great War to Gaza. Vancouver Island University Arts & Humanities Colloquium Series.
Rogers, A., & Hill, J. (2014). Unmanned: Drone warfare and global security. Between the Lines.
How Intelligent Drones Are Shaping the Future of Warfare , Rolling Stone Magazine
External links
Wireless
Avionics
Robotics | List of unmanned aerial vehicle applications | [
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56,002,487 | https://en.wikipedia.org/wiki/Engineering%20Critical%20Assessment | Engineering Critical Assessment (ECA) is a procedure by which the safety of a welded structure with defects or flaws can be determined. ECAs utilize the material properties and expected stress history to determine a flaw acceptance criteria which will ensure that welds will not fail during the construction or service life of the welded structure. The assessment can be used before the structure is in use, or during in-service inspection, to determine whether a given weld is in need of repair. ECAs are used throughout the energy, manufacturing, and infrastructure industries. ECAs are based heavily upon fracture mechanics principles, and reflect an improvement over traditional methods of weld quality assurance, which can be arbitrary or overly conservative.
Background
During welding, defects or flaws can develop. In some cases, these flaws could potentially affect the integrity of the weld, resulting in failure by fatigue, creep, brittle fracture, or yielding. Therefore, codes to determine weld quality must be developed. Traditionally, welding codes have been based on workmanship criteria. These criteria are determined empirically, typically by estimating the level of weld quality expected from a skilled welder. While these criteria have been reliable historically, improvements made in welding technology and materials science are not taken into account. As a result, over time, workmanship criteria have become increasingly conservative. This conservatism results in unnecessary repairs, which can increase construction costs and can yield undesirable residual stresses at the location of the repair weld.
Beginning in the late 1970s to early 1980s, engineering critical assessments began to emerge as an alternative to traditional workmanship criteria. These ECAs relied heavily on recent developments in the field of fracture mechanics. Where workmanship criteria were developed with a limited understanding of material characteristics, and considered only the length of a given weld flaw, these ECA-based flaw acceptance criteria considered additional factors such as:
The stress history of the weld, including all cyclic and static stresses expected throughout the life cycle of the welded structure
The strength of the base metal and weld material
The fracture toughness (measured via Crack tip opening displacement testing or Charpy impact testing) of the base metal and the weld material
The flaw orientation (e.g., measurement of flaw length and flaw height, as opposed to flaw length only)
Together, these additional factors allow for more generous flaw acceptance criteria, resulting in fewer unnecessarily repaired welds.
To comply with the flaw acceptance criteria developed during ECA, non-destructive examination must be utilized. Ultrasonic testing is typically used due to its high accuracy, ability to identify flaw size and orientation, and its ability to provide feedback instantly.
ECA for oil and gas pipelines
ECA-based flaw acceptance criteria are commonly used in the oil and gas industry, particularly with regard to qualification of girth welds on cross-country oil and gas transmission pipelines. This is because girth welds are typically uniform from weld to weld, allowing construction contractors to utilize mechanized welding. Mechanized welding increases productivity over manual welding techniques by allowing for better, more uniform control over weld characteristics. ECA-based flaw acceptance criteria are able to take advantage of the high strength and toughness of the welds produced to develop more generous flaw acceptance criteria. In addition, the flaws created during mechanized welding are typically oriented differently than flaws developed from manual welding. ECA-based flaw acceptance criteria more effectively assess these flaws, by considering flaw orientation, rather than just flaw length.
Standards
Several standards specific to ECAs for oil and gas pipelines have been developed. The most commonly used of these are API 1104 Appendix A, API 579, CSA Z662 Annex K, and BS 7910. The standard used depends primarily on the location of the pipeline being installed. The standards differ in methodology and in extreme cases, can result in significantly different flaw acceptance criteria. However, for typical operating conditions, the criteria are easy enough to follow that practical differences between the standards are small.
References
Safety engineering | Engineering Critical Assessment | [
"Engineering"
] | 813 | [
"Safety engineering",
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56,003,550 | https://en.wikipedia.org/wiki/Natural%20disturbance%20regime%20of%20the%20Sagebrush%20Sea%20of%20the%20Great%20Basin | The Sagebrush Sea, also called the sagebrush steppe, is an ecosystem of the Great Basin that is primarily centered on the 27 species of sagebrush that grow from sea level to about 12,000 feet. This ecosystem is home to hundreds of species of both fauna and flora. It includes small mammals such as pygmy rabbits, reptiles such as the sagebrush lizard, birds such as the golden eagles, and countless other species that are solely found in this ecosystem. This ecosystem at one point occupied over 62 million hectares in the western United States and southwestern Canada. It currently only occupies about 56 percent of historic range and is continuing to decline due to several factors.
Location
Sagebrush steppe ecosystems occur in Nevada and parts of Utah, Oregon, Idaho, and California. Its western edge is defined by the Sierra Nevada and the Cascade Range, and its eastern edge is the Wasatch Mountains. The northern boundary is the Snake river, and its southern boundary is defined by the Mojave Desert in California.
Threats
Some sagebrush ecosystems rely on recurrent fire. Due to the disruption of the fire cycle, several species have encroached on sagebrush. These species that threaten the sagebrush are:
Conifer woodlands
Conifer woodlands consist of two main species: Juniperus or Junipers and Pinus or Pinyon. These conifers are able to establish and increase in density to the point where sagebrush are outcompeted because they cannot get adequate sunlight and nutrients from the soil. This decline in sagebrush has fragmented sagebrush habitats and caused a disruption in the fauna (e.g., sage grouse). Predation may increase in fragment habitats due to lack of cover for the prey.
Exotic annual grasses
Several exotic grasses have come into these sagebrush ecosystem and have been labeled noxious weeds which is determined by the agricultural authority. The two main annual grasses that are causes much of the problems are: Bromus tectorum or cheatgrass and Agropyron cristatum or chested wheatgrass. Both species enter areas that have been recently disturbed and rapidly expand into their surroundings through massive growth and seed production. These grasses are so effective because they produce above ground biomass sooner and thicker than competitors and block them out. These exotic grasses alter the natural fire regime and cause an increase in fire frequencies because while these grasses outcompete early on they also dry out in the summer and provide fuel for fire that ultimately cause fires to spread faster and with greater frequency.
Fire
Fires are both a natural and man-made influence in these systems that help: reduce hazards, control species both desirable and undesirable, improve access and visibility, disease control, and lastly fires in these habitats have been used to create varying stages of succession in an area. Thus fires may increase biodiversity. For example, fires may reduce competition and provide opportunities for herbaceous flora. For the first three decades after a burn there is a drastic increase in the production of grasses, followed by a reestablishment of sagebrush. By having areas in varying stages of succession, the effects of major events like wildfires and diseases are likely to be less severe than if landscape patterns were more uniform.
Restoration efforts
Traditional conservation efforts usually focus on single species, which are extremely expensive and have finite results. Comprehensive conservation plans focus on entire ecosystems and benefit numerous species in a more effective way. Currently the Great Basin has seen more traditional conservation plans and would greatly benefit from a more comprehensive plan to help preserve the more than 350 species of sagebrush associated fauna and flora.
Conifer woodlands
Conifer woodlands are controlled primarily through the uses of chainsaws, heavy equipment and prescribed fires. This ensures that woodlands are reduced and sagebrush are restored by decreasing the woody fuel load and allowing adequate perennial fauna composition for restoration and recovery.
Exotic annual grasses
Exotic annual grasses are controlled through number of ways: physical removal, chemical means, introduction of cattle for grazing, and prescribed fires. All of which are extremely expensive and labor-intensive due to the rapid nature of its spread. All of these control methods can also be potentially harmful to sagebrush if not properly implemented.
References
Ecosystems
Nature conservation in the United States | Natural disturbance regime of the Sagebrush Sea of the Great Basin | [
"Biology"
] | 841 | [
"Symbiosis",
"Ecosystems"
] |
56,004,496 | https://en.wikipedia.org/wiki/Bidhu%20Bhushan%20Ray | Bidhu Bhushan Ray (also Bidhu Bhusan Ray, Bidhubhusan Ray and B. B. Ray) was an Indian physicist. He was a pioneer in the field of X-ray spectroscopy, and his laboratory was the first of its kind in India. Also notable are his contributions to studies related to scattering of light in the atmosphere. He played a significant role in facilitating contacts between Indian and European scientists. He was elected Fellow, Indian National Science Academy, and held the post of Khaira Professor of Physics at the Rajabazar Science College, University of Calcutta until the time of his death.
Early life
Bidhu Bhushan Ray was born on 1 July 1894 in Khadarpara, East Bengal, British India (now in Bangladesh). He completed his studies in Calcutta. His doctoral thesis was on the scattering of light in the atmosphere, carried out under the guidance of C. V. Raman. He obtained his D.Sc. in 1922. As part of his doctoral work, he gave a theory of glories, coronas and iridescent clouds, which is still considered relevant.
Career
In 1921, Ray was appointed as lecturer in physics at the University College of Science and Technology, University of Calcutta, where he would remain until his death. In 1923, he secured two years of leave to travel to Europe. He spent a few months working with Manne Siegbahn in Uppsala, where he started experimental work in X-ray spectroscopy. He then moved to Copenhagen to work with Niels Bohr, to whom Raman had already introduced him. Ray spent over a year in Copenhagen, doing theoretical work related to X-ray spectra. After leaving Copenhagen, he visited a number of other laboratories in Germany and Italy before returning to India.
Inspired by his stay in Europe, Ray decided to set up a laboratory for X-ray spectroscopy, which would be the first of its kind not only in Calcutta but in India. It was not easy to get the necessary financial support from the University of Calcutta. Bohr wrote as many as three letters to the university authorities recommending Ray's case for funding. In one of them he wrote: "..Dr. Ray must be considered as unusually qualified for such work (X-ray spectra and their interpretation), ... having ... a thorough knowledge of the present stand of the theories"
Ray was finally able to set up his research laboratory in 1927–28. Over the next fifteen years, he published a number of research papers in leading journals. Along with his work on X-ray spectroscopy, he also continued his meteorological studies. His laboratory became a training ground for young physicists, e.g. R. C. Majumdar. In 1935 he was appointed to the prestigious chair of Khaira Professor of Physics, a position he held until his untimely death.
Controversy
From 1930 onwards, Ray was involved in a scientific controversy. After the discovery of the Raman Effect, there was considerable international interest in trying to observe an analogous effect in X-rays. Researchers in the US and Germany had tried and reported negative results. In 1930, Bidhu Bhushan Ray reported, in a paper published in Nature, that he had observed additional spectral lines in scattered X-rays, which he interpreted as being analogous to Raman's observations. Immediately afterwards, J. M. Cork reported that he was unable to reproduce Ray's result. Ray wrote a rebuttal, and followed it up with more experimental work. The controversy continued for several years, and was finally settled in 1937 by Arnold Sommerfeld, who confirmed Ray's observations and also gave a detailed explanation of the phenomenon.
Death
Bidhu Bhushan Ray died of a heart attack on 29 July 1944, less than a month after his fiftieth birthday. Some of his family members believe that the controversy mentioned above was directly responsible for his death. Oral history has it that a demonstration was set up in his laboratory, where some colleagues and visitors were to be shown the extra spectral lines. When the visitors arrived, the demonstration did not work. Ray was ridiculed for this failure, and the resulting humiliation precipitated his heart attack. However, researcher Rajinder Singh, on the basis of his study of original documents, argues that this is not likely. He points out that the controversy had already been resolved in 1937, following Sommerfeld's work, more than six years before Ray's death. Moreover, the experiment required many hours of running time. Thus visual demonstration was not possible. Singh further notes that Ray had developed malaria and other ailments, which may have played a role in his early death.
Other contributions
Apart from his teaching and research work, Ray was also interested in the dissemination of science to a wider audience. He was a founding member and Secretary of the Indian Science News Association, established in 1935. He edited its journal, Science and Culture.
Awards and honours
Elected Fellow, National Institute of Science of India (later renamed Indian National Science Academy) in 1935
Appointed Khaira Professor of Physics, University of Calcutta, in 1935
Elected President, Physics Section, Indian Science Congress (1942)
Legacy
After C. V. Raman, B.B. Ray was the first Indian physicist to set up a research laboratory which yielded results that could be published in leading journals such as Nature. This undoubtedly provided an impetus to experimental physics in the country. While Ray received recognition in his lifetime, he was almost forgotten in the intervening decades, until a recent revival of interest. Rajinder Singh, who has written a book on Ray, calls him "an unsung hero in Indian science". Singh also argues that Ray's contacts with European scientists were important in themselves, and also facilitated such contacts for other Indian scientists, notably S. N. Bose and M. N. Saha.
The Indian Science News Association continues its activities, including the publication of Science and Culture.
References
1894 births
1944 deaths
Experimental physicists
Fellows of the Indian National Science Academy
Academic staff of the University of Calcutta
Scientists from Kolkata
People from British India | Bidhu Bhushan Ray | [
"Physics"
] | 1,247 | [
"Experimental physics",
"Experimental physicists"
] |
56,004,756 | https://en.wikipedia.org/wiki/NGC%201190 | NGC 1190 is a lenticular galaxy approximately 109 million light-years away from Earth in the constellation of Eridanus. It was discovered by American astronomer Francis Leavenworth on December 2, 1885 with the 26" refractor at Leander McCormick Observatory.
NGC 1190 is dominated by stellar light with little long wavelength emission.
Together with NGC 1189, NGC 1191, NGC 1192 and NGC 1199 it forms Hickson Compact Group 22 (HCG 22) galaxy group. Although they are considered members of this group, NGC 1191 and NGC 1192 are in fact background objects, since they are much further away compared to the other members of this group.
Image gallery
See also
Lenticular galaxy
Hickson Compact Group
List of NGC objects (1001–2000)
Eridanus (constellation)
References
External links
SEDS
Lenticular galaxies
Eridanus (constellation)
1190
11508
Hickson Compact Groups
Astronomical objects discovered in 1885
Discoveries by Francis Leavenworth | NGC 1190 | [
"Astronomy"
] | 199 | [
"Eridanus (constellation)",
"Constellations"
] |
56,005,174 | https://en.wikipedia.org/wiki/Cop%20number | In graph theory, a branch of mathematics, the cop number or copnumber of an undirected graph is the minimum number of cops that suffices to ensure a win (i.e., a capture of the robber) in a certain pursuit–evasion game on the graph.
Rules
In this game, one player controls the position of a given number of cops and the other player controls the position of a robber. The cops are trying to catch the robber by moving to the same position, while the robber is trying to remain uncaught. Thus, the players perform the following actions, taking turns with each other:
On the first turn of the game, the player controlling the cops places each cop on a vertex of the graph (allowing more than one cop to be placed on the same vertex).
Next, the player controlling the robber places the robber on a vertex of the graph.
On each subsequent turn, the player controlling the cops chooses a (possibly empty) subset of the cops, and moves each of these cops to adjacent vertices. The remaining cops (if any) stay put.
On the robber's turn, he may either move to an adjacent vertex or stay put.
The game ends with a win for the cops whenever the robber occupies the same vertex as a cop. If this never happens, the robber wins.
The cop number of a graph is the minimum number such that cops can win the game on .
Example
On a tree, the cop number is one. The cop can start anywhere, and at each step move to the unique neighbor that is closer to the robber. Each of the cop's steps reduces the size of the subtree that the robber is confined to, so the game eventually ends.
On a cycle graph of length more than three, the cop number is two. If there is only one cop, the robber can move to a position two steps away from the cop, and always maintain the same distance after each move of the robber. In this way, the robber can evade capture forever. However, if there are two cops, one can stay at one vertex and cause the robber and the other cop to play in the remaining path. If the other cop follows the tree strategy, the robber will eventually lose.
General results
Every graph whose girth is greater than four has cop number at least equal to its minimum degree. It follows that there exist graphs of arbitrarily high cop number.
Henri Meyniel (also known for Meyniel graphs) conjectured in 1985 that every connected -vertex graph has cop number . The Levi graphs (or incidence graphs) of finite projective planes have girth six and minimum degree , so if true this bound would be the best possible.
All graphs have sublinear cop number. One way to prove this is to use subgraphs that are guardable by a single cop: the cop can move to track the robber in such a way that, if the robber ever moves into the subgraph, the cop can immediately capture the robber. Two types of subgraph that are guardable are the closed neighborhood of a single vertex, and a shortest path between any two vertices. The Moore bound in the degree diameter problem implies that at least one of these two kinds of guardable sets has size . Using one cop to guard this set and recursing within the connected components of the remaining vertices of the graph shows that the cop number is at most .
A more strongly sublinear upper bound on the cop number,
is known. However, the problems of obtaining a tight bound, and of proving or disproving Meyniel's conjecture, remain unsolved. It is even unknown whether the soft Meyniel conjecture, that there exists a constant for which the cop number is always , is true.
Computing the cop number of a given graph is EXPTIME-hard, and hard for parameterized complexity.
Special classes of graphs
The cop-win graphs are the graphs with cop number equal to one.
Every planar graph has cop number at most three.
More generally, every graph has cop number at most proportional to its genus. However, the best known lower bound for
the cop number in terms of the genus is approximately the square root of the genus, which is
far from the upper bound when the genus is large.
The treewidth of a graph can also be obtained as the result of a pursuit-evasion game, but one in which the robber can move along arbitrary-length paths instead of a single edge in each turn. This extra freedom means that the cop number is generally smaller than the treewidth. More specifically,
on graphs of treewidth , the cop number is at most .
References
Graph invariants
Pursuit–evasion | Cop number | [
"Mathematics"
] | 961 | [
"Graph invariants",
"Mathematical relations",
"Graph theory"
] |
56,005,312 | https://en.wikipedia.org/wiki/Toxins%20%28journal%29 | Toxins is a monthly open-access scientific journal covering toxins and toxicology. Toxins is published monthly online by MDPI.
The French Society on Toxinology (SFET), International Society for Mycotoxicology (ISM), Japanese Society of Mycotoxicology (JSMYCO) and European Uremic Toxins (EUTox) Work Group are affiliated with Toxins.
The journal covers toxinology and all kinds of toxins (biotoxins) from animals, microbes and plants. Some types of toxins covered are: aflatoxins, exotoxins, endotoxins, neurotoxins, any other toxin from animal, plant or microbial origin.
Abstracting and indexing
The journal is abstracted and indexed in Index Medicus/MEDLINE/PubMed, Science Citation Index Expanded, and Scopus. Its 2017 impact factor is 3.273.
External links
Toxins: State of the Journal Report, 2017.
References
Toxicology journals
Open access journals
MDPI academic journals
English-language journals
Academic journals established in 2009 | Toxins (journal) | [
"Environmental_science"
] | 227 | [
"Toxicology journals",
"Toxicology"
] |
56,006,274 | https://en.wikipedia.org/wiki/Penny%20%26%20Giles | Penny & Giles (P&G) was a British engineering company in Dorset (former Hampshire) that made flight recorders (black boxes).
History
The company was founded in 1956 by Prof William Alfred Penny and James Giles. It made high-reliability wire-wound potentiometers for aircraft in flight testing.
In 1957 it made the first aircraft data recorder with magnetic recording on a stainless steel wire, known as a black box. In 1963, the Ministry of Aviation informed the UK aircraft industry that all civil airliners would have to have flight data recorders.
In April 1973, Penny and Giles Conductive Plastics received a Queen's Award for Enterprise: Innovation (Technology). It became known as Penny and Giles International, with four divisions. In April 1992 it won another Queen's Award for Enterprise.
In the 1990s it was known as Penny & Giles Data Recorders Limited, and claimed to be the world's leading manufacturer of aircraft data recorders.
Ownership
In 1992 it was bought by Bowthorpe Holdings for £30m.
The company was bought out in 2002 by Curtiss-Wright of the USA, and is now part of Curtiss-Wright Controls Integrated Sensing.
Structure
It was headquartered at Mudeford in Dorset.
Products
LVDT and RVDT transducers
Optical Quick Access Recorders (O-QAR) for civil airliners
See also
Teledyne Controls
References
External links
Grace's Guide
Penny & Giles Transducers
Aircraft component manufacturers of the United Kingdom
Aircraft recorders
Aviation history of the United Kingdom
British companies established in 1956
Companies based in Dorset
Curtiss-Wright Company
Manufacturing companies established in 1956 | Penny & Giles | [
"Technology"
] | 329 | [
"Aircraft recorders",
"Recording devices"
] |
56,006,371 | https://en.wikipedia.org/wiki/Aspergillus%20brunneoviolaceus | Aspergillus brunneoviolaceus is a species of fungus in the genus Aspergillus. It belongs to the group of black Aspergilli which are important industrial workhorses. A. brunneoviolaceus belongs to the Nigri section. The species was first described in 1955 and has been found in Brazil.
The genome of A. brunneoviolaceus was sequenced and published in 2014 as part of the Aspergillus whole-genome sequencing project – a project dedicated to performing whole-genome sequencing of all members of the genus Aspergillus. The genome assembly size was 37.48 Mbp.
Growth and morphology
A. brunneoviolaceus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid® (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
Further reading
brunneoviolaceus
Fungi described in 1955
Fungus species | Aspergillus brunneoviolaceus | [
"Biology"
] | 211 | [
"Fungi",
"Fungus species"
] |
56,006,558 | https://en.wikipedia.org/wiki/Aspergillus%20deflectus | Aspergillus deflectus is a species of fungus in the genus Aspergillus. It produces a group of antimicrobial chemical compounds known as deflectins. Aspergillus deflectus is in rare cases pathogenic. It is from the Usti section.
Growth and morphology
A. deflectus has been cultivated on both Czapek yeast extract agar (CYA) plates and Malt Extract Agar Oxoid (MEAOX) plates. The growth morphology of the colonies can be seen in the pictures below.
References
Further reading
deflectus
Fungi described in 1955
Fungus species | Aspergillus deflectus | [
"Biology"
] | 129 | [
"Fungi",
"Fungus species"
] |
56,006,782 | https://en.wikipedia.org/wiki/NGC%20501 | NGC 501, also occasionally referred to as PGC 5082 or GC 284, is an elliptical galaxy in the constellation Pisces. It is located approximately 224 million light-years from the Solar System and was discovered on 28 October 1856 by Irish astronomer R. J. Mitchell.
Observation history
Although John Dreyer, creator of the New General Catalogue, credits the discovery to astronomer William Parsons, 3rd Earl of Rosse, he notes that many of his claimed discoveries were made by one of his assistants. In the case of NGC 501, the discovery was made by R. J. Mitchell, who discovered it using Lord Rosse's 72" reflecting telescope at Birr Castle in County Offaly, Ireland. The object was described "very faint, small (E in Birr diagram)" in the New General Catalogue.
See also
Elliptical galaxy
List of NGC objects (1–1000)
Pisces (constellation)
References
External links
SEDS
Elliptical galaxies
Pisces (constellation)
0501
5082
Astronomical objects discovered in 1856
Discoveries by R. J. Mitchell (astronomer) | NGC 501 | [
"Astronomy"
] | 221 | [
"Pisces (constellation)",
"Constellations"
] |
59,402,449 | https://en.wikipedia.org/wiki/Robin%20Clark%20%28chemist%29 | Robin Jon Hawes Clark (16 February 1935 – 6 December 2018) was a New Zealand-born chemist initially noted for research of transition metal and mixed-valence complexes, and later for the use of Raman spectroscopy in determining the chemical composition of pigments used in artworks.
Early life and education
Clark was born in Rangiora, New Zealand on 16 February 1935, to parents Reginald Hawes Clark and Marjorie Alice Clark. He attended Marlborough College, Blenheim, and Christ's College, Christchurch before pursuing bachelor's and master's at Canterbury University College. Clark was a research and teaching fellow under William Fyfe at the University of Otago in 1958. From 1958 to 1961, Clark worked toward a doctorate advised by Ronald Sydney Nyholm and Jack Lewis at University College London and was awarded a PhD degree for his work on titanium complexes in 1961. The University of London later awarded Clark a DSc in 1969.
Career
Clark began teaching at University College London in 1962 as an assistant lecturer. He was appointed Sir William Ramsay Professor in 1989, and served until retirement in 2009. He served as the dean of science from 1988 to 1989 and later as head of the chemistry department from 1989 to 1999.
Clark died in London on 6 December 2018.
Artwork authentication
In 1992, Clark was asked to develop a non-destructive technique to analyze the chemical composition of a painting in such a way to be able to spot art forgeries. He had since developed the use of Raman spectroscopy as an important tool for use in the fields of artwork authentication, conservation, and preservation.
Awards and honours
Over the course of his career, Clark delivered several named lectures and received multiple awards. In 1969, he was elected a fellow of the Royal Society of Chemistry. In 1989, he was granted honorary fellowship by the Royal Society of New Zealand. He became a fellow of the Royal Society of London and member of the Academia Europaea in 1990. Two years later, he was elected a fellow of University College London and the Royal Society of Arts, and in 2001 he was conferred with an honorary DSc by the University of Canterbury. Clark was appointed a Companion of the New Zealand Order of Merit in the 2004 Queen's Birthday Honours, for services to science and New Zealand interests in the United Kingdom, followed by elections as a foreign fellow of the National Academy of Sciences, India in 2007 and as an international member of the American Philosophical Society in 2010. In 2009, Royal Society of Chemistry awarded Clark the Sir George Stokes Award for his contribution to the application of analytical science to the arts and archaeology through his development of Raman microscopy for the identification of pigments.
Selected works
References
1935 births
2018 deaths
New Zealand chemists
University of Canterbury alumni
Alumni of University College London
Academics of University College London
New Zealand emigrants to the United Kingdom
20th-century British chemists
21st-century British chemists
Fellows of the Royal Society
Fellows of the Royal Society of Chemistry
Members of Academia Europaea
Honorary Fellows of the Royal Society of New Zealand
Companions of the New Zealand Order of Merit
People from Rangiora
People educated at Marlborough Boys' College
People educated at Christ's College, Christchurch
Fellows of the National Academy of Sciences, India
Members of the American Philosophical Society
Spectroscopists | Robin Clark (chemist) | [
"Physics",
"Chemistry"
] | 652 | [
"Physical chemists",
"Spectrum (physical sciences)",
"Analytical chemists",
"Spectroscopists",
"Spectroscopy"
] |
59,403,236 | https://en.wikipedia.org/wiki/Morteza%20Gharib | Morteza (Mory) Gharib () (born December 9, 1952) is the Hans W. Liepmann Professor of Aeronautics and Bio-Inspired Engineering at Caltech.
Gharib was elected a member of the National Academy of Engineering in 2015 for contributions to fluid flow diagnostics and imagery, and engineering of bioinspired devices and phenomena.
Research
Professor Gharib's research interests cover a range of topics in conventional fluid dynamics and aeronautics. These include vortex dynamics, active and passive flow control, nano/micro fluid dynamics, bio-inspired wind and hydro energy harvesting, as well as advanced flow imaging diagnostics.
In addition, Professor Gharib is heavily involved in the bio-mechanics and medical engineering fields. His research activities in these fields can be categorized into two main areas: the fluid dynamics of physiological machines (such as the human circulatory system and aquatic breathing/ propulsion), and the development of medical devices (such as heart valves, cardiovascular health monitoring devices, and drug delivery systems).
Awards and honors
Professor Gharib is the recipient of the 2016 G. I. Taylor Medal from the Society of Engineering Science and he received the American Physical Society's Fluid Dynamics award in 2015. He's a Member of the American Academy of Arts and Sciences and the National Academy of Engineering; and he's a Fellow (Charter) of the National Academy of Inventors, the American Association for the Advancement of Science, the American Physical Society, the American Society of Mechanical Engineering and the International Academy of Medical and Biological Engineering.
References
American people of Iranian descent
American mechanical engineers
Fluid dynamicists
Iranian expatriate academics
Living people
California Institute of Technology alumni
University of Tehran alumni
1952 births
Fellows of the American Physical Society | Morteza Gharib | [
"Chemistry"
] | 355 | [
"Fluid dynamicists",
"Fluid dynamics"
] |
59,404,966 | https://en.wikipedia.org/wiki/Daryle%20H.%20Busch | Daryle Hadley Busch (March 30, 1928 – May 19, 2021) was an American inorganic chemist.
A native of Carterville, Illinois, born in 1928, Busch attended Southern Illinois University and earned a master's, and doctorate in chemistry from the University of Illinois. Upon graduation, he began teaching at the Ohio State University. Busch was awarded a Guggenheim fellowship in 1981. He retired from OSU in 1988, a year after he had been appointed to a presidential professorship. Busch then joined the University of Kansas faculty as Roy A. Roberts Distinguished Professor of Chemistry. He was president of the American Chemical Society in 2000.
References
1928 births
2021 deaths
20th-century American chemists
21st-century American chemists
Southern Illinois University alumni
Ohio State University faculty
University of Kansas faculty
American inorganic chemists
Presidents of the American Chemical Society
People from Carterville, Illinois
Scientists from Illinois
University of Illinois College of Liberal Arts and Sciences alumni | Daryle H. Busch | [
"Chemistry"
] | 185 | [
"American inorganic chemists",
"Inorganic chemists"
] |
59,406,172 | https://en.wikipedia.org/wiki/Biomarkers%20of%20diabetes | Diabetes mellitus (DM) is a type of metabolic disease characterized by hyperglycemia. It is caused by either defected insulin secretion or damaged biological function, or both. The high-level blood glucose for a long time will lead to dysfunction of a variety of tissues.
Type 2 diabetes is a progressive condition in which the body becomes resistant to the normal effects of insulin and/or gradually loses the capacity to produce enough insulin in the pancreas.
Pre-diabetes means that the blood sugar level is higher than normal but not yet high enough to be type 2 diabetes.
Gestational diabetes is a condition in which a woman without diabetes develops high blood sugar levels during pregnancy.
Type 2 diabetes mellitus and prediabetes are associated with changes in levels of metabolic markers, these markers could serve as potential prognostic or therapeutic targets for patients with prediabetes or Type 2 diabetes mellitus.
Metabolic markers
Oxytocin (OXT)
Omentin
Endothelin-1
Nesfatin-1
Irisin
Betatrophin
Hepatocyte growth factor (HGF)
Fibroblast growth factor
-Biomarkers with insulin-sensitizing properties (irisin, omentin, oxytocin)
-Biomarkers of metabolic dysfunction (HGF, Nesfatin and Betatrophin)
Biomarkers with insulin-sensitizing properties
Oxytocin
Oxytocin (OXT), a hormone most commonly associated with labor and lactation, may have a wide variety of physiological and pathological functions, which makes Oxytocin and its receptor potential targets for drug therapy.
OXT may have positive metabolic effects; this is based on the change in glucose metabolism, lipid profile, and insulin sensitivity. It may modify glucose uptake and insulin sensitivity both through direct and indirect effects. It may also cause regenerative changes in diabetic pancreatic islet cells. So, the activation of the OXT receptor pathway by infusion of OXT, OXT analogues, or OXT agonists may represent a promising approach for the management of obesity and related metabolic diseases as well as diabetes and its complications.
Oxytocin improves insulin sensitivity by:
Reducing Gluco-toxicity and Lipo-toxicity.
Regulating cytokines like leptin and adiponectin.
OXT decreased fat mass, resulting in reduction in leptin level.
Oxytocin may cause β-cell regeneration by:
OXT decreases pancreatic islet hypertrophy.
OXT has antioxidant and anti-inflammatory effects.
Pancreatic islet inflammation is an important factor in the pathogenesis of diabetes. The protection of β-cells from death is considered as a new therapeutic target.
The hypoglycaemic effect, stimulatory effect on insulin secretion and sensitivity, and improvement of pancreatic islet cells after OXT administration, strongly suggested that OXT might be a therapeutic target for treating diabetes
Deficits in OXT or its receptor developed hyperleptinemia and late-onset obesity with increases in abdominal fats and fasting plasma triglycerides
The balance of leptin and adiponectin in diabetic patients can be used as a predictor of insulin resistance and a useful indicator for the choice of drug to treat diabetes mellitus
Oxytocin levels:
OXT was negatively and significantly correlated with HbA1c, FGF21, HGF and positively correlated with both irisin and gender.
OXT levels higher in normoglycemic as compared to pre-DM/T2DM patients.
OXT are reduced in patient with pre-DM/Type2 DM.
Omentin
Omentin is an anti-inflammatory adipokine produced preferentially by visceral adipose tissue. Plasma omentin-1 levels are significantly decreased in patients with obesity, insulin resistance and diabetes that contribute to the major components of the metabolic syndrome. Insulin resistance contributes to the changes of cholesterol synthesis and absorption as well. However, nothing is known about the relationship between Omentin and metabolic risk factors. So a study were held in Japan comprised 201 Japanese men who underwent annual health check-ups. Plasma Omentin levels were determined by enzyme-linked immunosorbent assay. They divided the subjects into 4 groups according to Omentin levels. A reduction of plasma Omentin levels significantly correlated with an increase in the mean number of metabolic risk factors such as increased waist circumference, Dyslipidemia, high blood pressure and glucose intolerance. They concluded that Circulating Omentin levels are negatively correlated with the multiplicity of metabolic risk factors, suggesting that Omentin acts as a biomarker of metabolic disorders.
Irisin
Irisin, a newly identified hormone, was first reported by Bostromet al. in 2012, is a novel myokine which plays an important role in the homeostasis, metabolism and energy balance. Irisin is reported to be involved in insulin resistance in both humans and animal models. Circulating irisin levels progressively decrease with the worsening of the glucose tolerance.
A recent study conducted a comparative cross-sectional evaluation of baseline circulating levels of the novel hormone Irisin and the established adipokine adiponectin with metabolic syndrome, cardio-metabolic variables and cardiovascular disease risk, and they found out that the baseline irisin levels were significantly higher in subjects with metabolic syndrome than in subjects without metabolic syndrome.
Biomarkers of metabolic dysfunction
Nesfatin-1
Nesfatin-1 is a peptide secreted by peripheral tissues, central and peripheral nervous system. It is involved in the regulation of energy, homeostasis related with food regulation and water intake.
Nesfatin-1 can pass through the blood-brain barrier in both directions. It suppresses feeding independently from the leptin pathway and increases insulin secretion from pancreatic beta islet cells. this is demonstrated by in-vitro studies that Nesfatin-1 stimulates the Preproinsulin mRNA expression and increases the glucose induced insulin release. That is why nesfatin-1 has drawn attention as a new therapeutic agent, especially for the treatment of obesity and diabetes mellitus.
In T2DM patients Nesfatin-1 is elevated and this could possibly be as a result of a resistance. Thus, Nesfatin-1 acts as a potent Anorexigenic factor (anti-obesity) that improves insulin resistance and opposes weight gain.
Hepatocyte growth factor (HGF)
Hepatocyte growth factor (HGF) is a mitogen and insulin tropic agent for the β cell. Inadequate β-cell mass can lead to insulin insufficiency and diabetes. During times of prolonged metabolic demand for insulin, the endocrine pancreas can respond by increasing β-cell mass, both by increasing cell size and by changing the balance between β-cell proliferation and apoptosis.
It is important to know the effects of high glucose on the factors that may influence endothelial cell growth. A novel member of endothelium-specific growth factors, hepatocyte growth factor (HGF), is produced in vascular cells. In diabetic patient's, levels of the hepatocyte growth factor (HGF) were found in high levels, thus independently associated with increased the incidence of diabetes.
There is a study that indicate that HGF/c-Met signalling is essential for maternal β-cell adaptation during pregnancy and that its absence/attenuation leads to gestational diabetes mellitus.
Betatrophin:
is a novel protein predominantly expressed in human liver and adipose tissues. Increasing evidence has revealed an association between betatrophin expression and serum lipid profiles, particularly in patients with obesity or diabetes, Thus betatrophin is closely related to diabetes treatment, it promotes greatly the proliferation of pancreatic beta cells, plays an important role in modulating glycolipid metabolism, and maybe replaces insulin in the effective treatment of diabetes.
studies showed that betatrophin could increase the quantity of cells that produce insulin in mice quickly. Others showed that the circulating level of betatrophin in T2DM patient blood was higher than that in control groups.
Expression of betatrophin correlates with β cell proliferation. Transient expression of betatrophin in mouse liver significantly and specifically promotes pancreatic β cell proliferation, expands β cell mass, and improves glucose tolerance. Thus, betatrophin treatment could augment or replace insulin injections by increasing the number of endogenous insulin-producing cells in diabetics.
Others
Endothelin-1(ET-1)
Is a vasoconstrictor peptide released from vascular endothelial cells. At the cellular level, the balance between vasodilator (Nitric oxide) and vasoconstrictor (ET-1) actions determines the vascular response to insulin. So, high levels of ET-1, which achieved in insulin resistance states that includes patients that have T2DM or metabolic syndromes or they are obese, have inhibitory effect on nitric oxide production which results in low nitric oxide and heightened levels of ET-1.
ET-1 activity is also enhanced secondary to abnormalities in vascular insulin signalling, In addition to its direct vasoconstrictor effects. Furthermore, ET-1 induces a reduction in insulin sensitivity and may take part in the development of the metabolic syndrome.
PVAT AND ET-1
ET-1 In addition to its direct vasoconstrictor effects, it causes changes in visceral and perivascular adipose tissue (PVAT), and may contribute to the pathogenesis of both insulin resistance and vascular dysfunction/damage. Perivascular adipose tissue seems to have anti contractile effect and this dilator effect was lost in obese patients.
secondary to obesity, ET-1 high level changes on PVAT will lead to PVAT hypertrophy which will be associated with reduced partial oxygen pressure, an increase in the production of inflammatory cytokines such as TNF-α and IL-6, and elevation of reactive oxygen species. Thus, oxidative stress and hypoxia may promote imbalance in the production of vasoactive compounds and may affect vascular homeostasis by activating the ET-1 system.
Fibroblast growth factor
fibroblast growth factor (FGF-21) has been recently characterized as a potent metabolic regulator. Systemic administration of FGF-21 reduced plasma glucose and triglycerides to near normal levels in genetically compromised diabetic rodents.
FGF21 can function as a crucial regulator mediating beneficial metabolic effects of therapeutic agents such as metformin, glucagon/glucagonlike peptide1analogues, thiazolidinedione, sirtuin 1 activators, and lipoic acid. A study showed that when fibroblast growth factor-21 administered daily for 6 weeks to diabetic rhesus monkeys, it caused a dramatic decline in fasting plasma glucose, fructosamine, triglycerides, insulin and glucagon. In a significant point during the study, FGF-21 administration also led to significant improvements in lipoprotein profiles and a beneficial changes in the circulating levels of several cardiovascular risk markers. And the induction of a small but significant weight loss. These data support the development of FGF-21 for the treatment of diabetes and other metabolic diseases.
References
Diabetes
Biomarkers
Medical signs | Biomarkers of diabetes | [
"Biology"
] | 2,395 | [
"Biomarkers"
] |
59,407,518 | https://en.wikipedia.org/wiki/Cybersecurity%20and%20Infrastructure%20Security%20Agency%20Act | The Cybersecurity and Infrastructure Security Agency Act of 2018 (, ) was signed by president Donald Trump on November16, 2018, to establish the Cybersecurity and Infrastructure Security Agency under the Department of Homeland Security. The act was introduced into the United States House of Representatives by Michael McCaul (R-TX-10) on July 24, 2017. It received committee consideration from the House Homeland Security, House Energy and Commerce, House Oversight and Government Return, and House Transportation and Infrastructure, though it was discharged by the Committee on Energy and Commerce, the Committee on Government Oversight and Return, and the Committee on Transportation. It passed the House of Representatives on December 11, 2017, via vocal vote, passed the Senate on October 3, 2018, by unanimous consent, and agreed upon by the House again on November 13, 2018.
References
External links
Cybersecurity and Infrastructure Security Agency Act of 2018 as amended (PDF/details) in the GPO Statute Compilations collection
Cybersecurity and Infrastructure Security Agency Act of 2018 as enacted (PDF/details) in the US Statutes at Large
H.R. 3359 at Congress.gov
Acts of the 115th United States Congress
Computer law
United States Department of Homeland Security | Cybersecurity and Infrastructure Security Agency Act | [
"Technology"
] | 249 | [
"Computer law",
"Computing and society"
] |
59,407,858 | https://en.wikipedia.org/wiki/NGC%20541 | NGC 541 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of about 230 million light years from Earth, which, given its apparent dimensions, means that NGC 541 is about 130,000 light years across. It was discovered by Heinrich d'Arrest on October 30, 1864. It is a member of the Abell 194 galaxy cluster and is included in the Atlas of Peculiar Galaxies in the category galaxies with nearby fragments. NGC 541 is a radio galaxy of Fanaroff–Riley class I, also known as 3C 40A (3C 40B is more prominent and is associated with the nearby galaxy NGC 547).
The galaxy was observed by the Hubble Space Telescope. It was found that it has a central disk seen nearly face-on with a diameter of 1".8. Inside the disk is an inner ring with a diameter of circa 0".44 arcseconds, which may be part of a hardly-visible spiral structure. There is also a linear dust feature sticking out of the disk with nearly the same axis as the radio jet. H-alpha and [N II] emission presented a peak at the centre of the dusk disk and also was found to form a ring around the peak, which had two brighter spots lying diametrically opposed. Observations in CO emission revealed the presence of molecular gas in NGC 541, with estimated mass of approximately 108 , and with a compact ring-like distribution with a radius of 1–2 kpc. In the centre of NGC 541 lies a supermassive black hole whose mass is estimated to be (1.9 – 9.2) × 108 .
At 45 arcseconds northeast of NGC 541 lies an irregular dwarf galaxy known as Minkowski's object. It is located in the path of the radio jet of NGC 541 and there is strong evidence that the jet has caused a starburst in Minkowski's object. There is a HI region downstream from the Minkowski's object with that straddles the jet at the point where the jet changes direction. At least 20 regions with star clusters and associated HII regions have been detected in Minkowski's object. The stellar population in Minkowski's object is dominated by stars formed in a single event 7.5 million years ago. The current starbirth rate is 0.52 per year. Although it has been proposed that Minkowski's object was a dwarf galaxy that happened to pass through the radio jet of NGC 541, it is more probable that the HI region was warm intergalactic gas that was cooled by the jet, resulting in star formation, a model that has been reproduced by computer stimulations.
A stellar bridge has been detected between NGC 541 and the galaxy pair NGC 545/547, which lies 4.5 arcminutes to the northeast (projected distance circa 100 kpc).
References
External links
NGC 541 on SIMBAD
Lenticular galaxies
Radio galaxies
Cetus
0541
01004
133
005305
+00-04-137
Astronomical objects discovered in 1864 | NGC 541 | [
"Astronomy"
] | 633 | [
"Cetus",
"Constellations"
] |
59,409,110 | https://en.wikipedia.org/wiki/Magnetic%20topological%20insulator | In physics, magnetic topological insulators are three dimensional magnetic materials with a non-trivial topological index protected by a symmetry other than time-reversal. This type of material conducts electricity on its outer surface, but its volume behaves like an insulator.
In contrast with a non-magnetic topological insulator, a magnetic topological insulator can have naturally gapped surface states as long as the quantizing symmetry is broken at the surface. These gapped surfaces exhibit a topologically protected half-quantized surface anomalous Hall conductivity () perpendicular to the surface. The sign of the half-quantized surface anomalous Hall conductivity depends on the specific surface termination.
Theory
Axion coupling
The classification of a 3D crystalline topological insulator can be understood in terms of the axion coupling . A scalar quantity that is determined from the ground state wavefunction
.
where is a shorthand notation for the Berry connection matrix
,
where is the cell-periodic part of the ground state Bloch wavefunction.
The topological nature of the axion coupling is evident if one considers gauge transformations. In this condensed matter setting a gauge transformation is a unitary transformation between states at the same point
.
Now a gauge transformation will cause , . Since a gauge choice is arbitrary, this property tells us that is only well defined in an interval of length e.g. .
The final ingredient we need to acquire a classification based on the axion coupling comes from observing how crystalline symmetries act on .
Fractional lattice translations , n-fold rotations : .
Time-reversal , inversion : .
The consequence is that if time-reversal or inversion are symmetries of the crystal we need to have
and that can only be true if (trivial),(non-trivial) (note that and are identified) giving us a classification. Furthermore, we can combine inversion or time-reversal with other symmetries that do not affect to acquire new symmetries that quantize . For example, mirror symmetry can always be expressed as giving rise to crystalline topological insulators, while the first intrinsic magnetic topological insulator MnBiTe has the quantizing symmetry .
Surface anomalous hall conductivity
So far we have discussed the mathematical properties of the axion coupling. Physically, a non-trivial axion coupling () will result in a half-quantized surface anomalous Hall conductivity () if the surface states are gapped. To see this, note that in general has two contribution. One comes from the axion coupling , a quantity that is determined from bulk considerations as we have seen, while the other is the Berry phase of the surface states at the Fermi level and therefore depends on the surface. In summary for a given surface termination the perpendicular component of the surface anomalous Hall conductivity to the surface will be
.
The expression for is defined because a surface property () can be determined from a bulk property () up to a quantum. To see this, consider a block of a material with some initial which we wrap with a 2D quantum anomalous Hall insulator with Chern index . As long as we do this without closing the surface gap, we are able to increase by without altering the bulk, and therefore without altering the axion coupling .
One of the most dramatic effects occurs when and time-reversal symmetry is present, i.e. non-magnetic topological insulator. Since is a pseudovector on the surface of the crystal, it must respect the surface symmetries, and is one of them, but resulting in . This forces on every surface resulting in a Dirac cone (or more generally an odd number of Dirac cones) on every surface and therefore making the boundary of the material conducting.
On the other hand, if time-reversal symmetry is absent, other symmetries can quantize and but not force to vanish. The most extreme case is the case of inversion symmetry (I). Inversion is never a surface symmetry and therefore a non-zero is valid. In the case that a surface is gapped, we have which results in a half-quantized surface AHC .
A half quantized surface Hall conductivity and a related treatment is also valid to understand topological insulators in magnetic field giving an effective axion description of the electrodynamics of these materials. This term leads to several interesting predictions including a quantized magnetoelectric effect. Evidence for this effect has recently been given in THz spectroscopy experiments performed at the Johns Hopkins University.
Experimental realizations
Magnetic topological insulators have proven difficult to create experimentally. In 2023 it was estimated that a magnetic topological insulator might be developed in 15 years' time.
A compound made from manganese, bismuth, and tellurium (MnBi2Te4) has been predicted to be a magnetic topological insulator. In 2024, scientists at the University of Chicago used MnBi2Te4 to develop a form of optical memory which is switched using lasers. This memory storage device could store data more quickly and efficiently, including in quantum computing.
References
Condensed matter physics
Magnetism | Magnetic topological insulator | [
"Physics",
"Chemistry",
"Materials_science",
"Engineering"
] | 1,038 | [
"Phases of matter",
"Condensed matter physics",
"Matter",
"Materials science"
] |
59,409,397 | https://en.wikipedia.org/wiki/State%20Institute%20for%20Drug%20Control | The State Institute for Drug Control () is a Czech government agency responsible for regulation of the safe production of pharmaceuticals in the country, clinical evaluation of medicines and for monitoring the advertising and marketing of both medicines and medical devices. Its powers stem from the Act on Public Health Insurance (Act No. 48/1997 Coll.).
Only part of its operating costs are directly funded. It is largely self-financing through charges for its services.
The SÚKL sets maximum ex-factory prices for reimbursement based on 195 reference groups of therapeutically interchangeable products of similar clinical efficacy. More than 20% of the health budget is spent on medication and medical devices. From January 2019 it took responsibility for regulating the reimbursement of consumer medical devices prescribed as part of outpatient care.
It allocates codes and names of medications for use in the electronic prescribing system.
It has been criticised by KOPAC, the Patient Association for Cannabis Treatment, for failing to ensure a supply of Czech medical cannabis so that patients have to pay inflated prices for imported supplies.
References
Pharmacy organizations
Medical and health organizations based in the Czech Republic
National agencies for drug regulation
1952 establishments in Czechoslovakia
Organizations established in 1952 | State Institute for Drug Control | [
"Chemistry"
] | 244 | [
"National agencies for drug regulation",
"Drug safety"
] |
59,409,767 | https://en.wikipedia.org/wiki/Suchi%20Saria | Suchi Saria is an Associate Professor of Machine Learning and Healthcare at Johns Hopkins University, where she uses big data to improve patient outcomes. She is a World Economic Forum Young Global Leader. From 2022 to 2023, she was an investment partner at AIX Ventures. AIX Ventures is a venture capital fund that invests in artificial intelligence startups.
Early life and education
Saria is from Darjeeling. She earned her bachelor's degree at Mount Holyoke College. She was awarded a full scholarship from Microsoft. In 2004 she joined Stanford University as a Rambus Corporation Fellow. She earned her Master of Science and Doctor of Philosophy degrees at Stanford University, supervised by Daphne Koller and advised by Anna Asher Penn and Sebastian Thrun. At Stanford University, Saria developed a statistical model that could predict premature baby outcomes with a 90% accuracy. The model used data from monitors, birth weight and length of time spent in the womb to predict whether a preemie would develop an illness. She worked in the startup Aster Data Systems.
Career and research
Saria believes that big data can be used to personalise healthcare. She is considered an expert in computational statistics and their applications to the real world. She uses Bayesian and probabilistic modelling. In 2014 Saria was funded by a $1.5 million Gordon and Betty Moore Foundation project that looked to make intensive care units safer. The project used data collected at patients' bedsides along with noninvasive 3D sensors that monitor care in patient's hospital rooms. The sensors collect information on steps that might have been missed by doctors; like washing hands.
Saria uses big data to manage chronic diseases. She is part of a National Science Foundation (NSF) award that looks at scleroderma. She uses machine learning to analyse medical records and identify similar patterns of disease progression. The system works out which treatments have been effectively used for various symptoms to aid doctors in choosing treatment plans for specific patients. She has developed another algorithm that can be used to predict and treat Septic shock. The algorithm used 16,000 items of patient health records and generates a targeted real-time warning (TREWS) score. She collaborated with David N. Hager to use the algorithm in clinics, and it was correct 86% of the time. Saria modified the algorithm to avoid missing high risk patients- for example, those who have suffered from septic shock previously and who have sought successful treatment. She was described by XRDS magazine as being a Pioneer in transforming healthcare. In 2016 Saria spoke at about using machine learning for medicine at TEDxBoston. The talk has been viewed over 100,170 times.
Awards and honours
Her awards and honors include:
2018 Sloan Research Fellowship
2018 World Economic Forum Young Global Leader
2017 MIT Technology Review 35 Innovators Under 35
2017 Defense Advanced Projects Research Agency (DARPA) Young Faculty Fellowship
2016 Brilliant 10 award by Popular Science
2015 IEEE Intelligent Systems Young Star in Artificial Intelligence
2015 Johns Hopkins Discovery Award
2014 National Science Foundation (NSF) Smart and Connected Health Research Grant
2014 Google Research Award
2014 Society of Critical Care Medicine Annual Scientific Award
2013 Gordon and Betty Moore Foundation Research Award
References
American academics of Indian descent
1980s births
Living people
Mount Holyoke College alumni
Stanford University alumni
People from Darjeeling
Johns Hopkins University faculty
Women data scientists
Data scientists
Bioinformaticians | Suchi Saria | [
"Biology"
] | 679 | [
"Bioinformatics",
"Bioinformaticians"
] |
59,410,798 | https://en.wikipedia.org/wiki/Hetherington%20Prize | The Hetherington Prize has been awarded once a year since 1991 at Oxford University for the best doctoral thesis presentation in the Department of Materials. The first ever prize (1991) was awarded to Prof. Kwang-Leong Choy (D.Phil., DSc, FIMMM, FRSC, CSci), who went on to become the Director of the Institute for Materials Discovery at University College London and Fellow of the Royal Society of Canada.
The award is almost exclusively awarded to only one doctoral candidate per year, but in two years it was shared (in 2011 to Nike Dattani and Lewys Jones, and in 2015 to Nina Klein, Aaron Lau, and Joe O'Gorman).
List of notable winners of the Hetherington Prize
References
1991 establishments in England
Awards established in 1991
Awards and prizes of the University of Oxford
Materials science awards | Hetherington Prize | [
"Materials_science",
"Technology",
"Engineering"
] | 175 | [
"Science and technology awards",
"Materials science awards",
"Materials science"
] |
59,412,730 | https://en.wikipedia.org/wiki/Water%20supply%20and%20sanitation%20in%20Lesotho | Lesotho is a mountainous and fairly 'water-rich country', but suffers from a lack of clean drinking water due to inadequate sanitation. In recent decades, with the construction of dams for the Lesotho Highlands Water Project (LHWP), Lesotho has become the main provider of water to parts of northern South Africa. Despite the economic and infrastructure development occasioned by the LHWP, waterborne diseases are common in the country and the infant mortality rate from them is high. In 2017, a project to improve the rural water supply in the Lesotho Lowlands was funded by the Global Environment Facility and the African Development Bank, and is ongoing.
Clean water and sanitation
Lesotho faces issues with clean water and sanitation; most notably access to drinkable water sources that are uncontaminated and inadequate public sanitation. With a government that does not support many large water projects to improve infrastructure and hygienic practices because they consider them to be cost ineffective, little progress has been made in providing clean water and sanitation to the citizens of Lesotho. Foreign and Lesotho NGOs play an important role in the region, especially in the more rural confines of the country.
History
The idea for the Lesotho Highlands Water Project (LHWP) originated in the late 1970s; however, it was not until a military coup had overthrown the government of Lesotho in 1986 that the project was established. The LHWP was a cooperation between South Africa and Lesotho's newly-installed government, although the arrangement played clearly in South Africa's favor. The project was such that South Africa would construct a five-series set of dams starting in the Lesotho Highlands by digging tunnels within the gorges of the Maluti Mountains, taking the southern flow of the Malibamatso River and directing it north towards South Africa.
The LHWP was estimated at a budget of US$5.6 billion and included a hydroelectric plant that Lesotho alone was responsible for constructing alongside these dams. The Lesotho government had sold their citizens on the idea of economic gain from such a large project. With the assistance of the Development Bank of South Africa (DBSA) and World Bank (WB) funding the dams, and the European Community funding the hydroelectric component, the project came into being with construction planned over the next 30 years, overshooting Lesotho's 5-year development plan cycles, and was to have been completed by 2016. The first dam was scheduled to be completed by 1996.
Microbial examination
The World Health Organization (WHO) conducted a study between July 1992 and January 1993 on the region within approximately 1,000 sq. miles of the 20-year old hydroelectric facility that resulted from the LHWP. The study included 72 remote villages' water sources. Three categories helped identify the levels of contamination and whether or not these were safe sources of consumable water for the villagers: unimproved was considered a natural source of water from open springs, and reservoirs; semi-improved indicated that the source of water had been manipulated or treated to inhibit human and animal contamination; improved water sources were usually completely covered and protected from outside elements with channels that secluded the source of water into silt-boxes for later consumption, further eliminating contamination.
The WHO also surveyed 588 households about their access to clean water: 38% of the 588 households claimed they had access to improved water sources. However, fewer than 5% used pit latrines and 18% of children under the age of five had experienced diarrheal illnesses within the two weeks prior to the study. The study found that most unimproved and semi-improved sources of drinking water had a presence of total Coliform (TC) and Escherichia coli (E. coli) exceeding the standards set by the U.S. Environmental Protection Agency (EPA) at approximately >16 organisms per 100 ml, compared to the EPA standard of <1 organism per 100ml, preferably non-existent. In addition, 83% of all improved water sources were found to be E. coli ridden.
The WHO concluded that because of the LHWP, the service roads built were a sign of slow infrastructure improvement and that the surrounding communities should stay patient as infrastructure for water supplies should follow in the years to come. Except for the more rural mountainous areas that have no accessible roads available all year round and their contamination of drinkable water has stayed intact. They suggested that villagers begin to implement hygienic habits that discontinue self-pollution and defecation within their own natural resources.
A similar study followed about two decades later. Conducted in 2011, the Department of Environmental Health (DEH) at the University of Lesotho examined the microbacterial contaminants in the drinking water of the Maseru district of the Manonyane community. Their scientific study included 22 springs, 6 open wells, 6 private boreholes and 1 open reservoir. They also conducted household surveys to assess the citizens' hygienic practices in and around the water sources sampled.
The surveys revealed the lack of consideration of contamination of local drinking water. Whether it was laundry run-off or leaking pit latrines or livestock feces, the lack of consideration was apparent because the citizens were not properly educated on the hygienic process. This poor sanitation has led to 1.6 million child deaths under the age of five because 84% of children reside in rural communities.
The water sources sampled were analyzed within a 6-hour timeframe and properly stored within a cool refrigerator on the way to the lab for accurate results. What they found in the samples was compared to the WHO definition of acceptable fecal matter and associated rick categories (chart below).
Of the 35 water sources sampled, 34 of the drinkable water sources exceeded the WHO no-risk guidelines of 0 cfu/100 ml of water, while 50% of the 34 were at high risk of contamination. Even the sources of water considered improved had experienced recent rainfall that leaked contaminated fecal matter into the water.
The DEH used this study to convey the issues of hygienic practices and lack of routine inspection of protected water sources. Their suggestion is for the citizens of the Manonyane community to implement health programs that educate the villagers to begin practicing safer hygienic techniques, like discontinuing laundry near water sources and using latrines that are fortified and unable to leak, as well as keeping livestock clear away from human drinking water sources to decrease human and animal contamination within their local water sources.
Water insecurity
The government of Lesotho has had failed projects to bring drinkable and sanitary water and sanitation services to the rural communities of Lesotho. These failed attempts have left the government to focus less on the impending costs of overhauling sanitary water conditions in favor of more lucrative ventures. In turn the people of Lesotho have had increasing numbers of water-borne diseases. Studies have shown correlation to poor access of clean water as a source of household illness and a large demographic epidemic by HIV/AIDS. These insecurities cause negative thoughts and feelings about the water the citizens of Lesotho consume. With the introduction and increased spread of HIV/AIDS over the past decades, Lesotho has seen it affect more skilled water and sanitation workers, ultimately leading to their deaths. This decreases the availability of clean water, which in turns leads to lower access due to droughts and climate change. These syndemic issues have been growing more apparent and have yet to be addressed.
Recent developments
On February 13, 2017 the Global Environment Facility (GEF) in partnership with the African Development Bank (AfDB) decided to finance the climate change adaptation for Sustainable Rural Water Supply in the Lesotho Lowlands. The GEF will be funding $4.4 million and the AfDB $17 million respectively. This project is to improve clean water and sanitation for the rural communities of the Lesotho Lowlands in response to recent climate change and managing resources more efficiently after the recent drought. The project will help sustain rural communities with potable water. Their plan is to implement watersheds to protect imported water supply from reoccurring droughts and possible floods.
The funds will be distributed through the Least Developed Countries Fund (LDCF), established under the United Nations Framework Convention on Climate Change. This project is in direct correlation with the National Adaptation Plans of Lesotho to improve the water and sanitation supply of their country, especially in rural communities. The funds will address sustainability of resources and inspire innovation for more jobs and economic growth within the guidelines of the Bank's Strategy for 2013–2022.
The second phase of the Lesotho Lowlands Water Supply Scheme, the Lowlands Water Development Project, seeks to increase water security and climate resilience in four areas of Lesotho's Lowlands. The project will address the nation's susceptibility to the detrimental effects of climate change on water security by including infrastructure to generate clean water in large quantities, enhance distribution networks and sanitation, and boost the efficiency of water usage. The project will also receive €116 million in funding from the European Investment Bank.
References
Infrastructure in Lesotho
Energy infrastructure in Lesotho
Water supply | Water supply and sanitation in Lesotho | [
"Chemistry",
"Engineering",
"Environmental_science"
] | 1,861 | [
"Hydrology",
"Water supply",
"Environmental engineering"
] |
59,413,690 | https://en.wikipedia.org/wiki/Kerr%E2%80%93Dold%20vortex | In fluid dynamics, Kerr–Dold vortex is an exact solution of Navier–Stokes equations, which represents steady periodic vortices superposed on the stagnation point flow (or extensional flow). The solution was discovered by Oliver S. Kerr and John W. Dold in 1994. These steady solutions exist as a result of a balance between vortex stretching by the extensional flow and viscous diffusion, which are similar to Burgers vortex. These vortices were observed experimentally in a four-roll mill apparatus by Lagnado and L. Gary Leal.
Mathematical description
The stagnation point flow, which is already an exact solution of the Navier–Stokes equation is given by , where is the strain rate. To this flow, an additional periodic disturbance can be added such that the new velocity field can be written as
where the disturbance and are assumed to be periodic in the direction with a fundamental wavenumber . Kerr and Dold showed that such disturbances exist with finite amplitude, thus making the solution an exact to Navier–Stokes equations. Introducing a stream function for the disturbance velocity components, the equations for disturbances in vorticity-streamfunction formulation can be shown to reduce to
where is the disturbance vorticity. A single parameter
can be obtained upon non-dimensionalization, which measures the strength of the converging flow to viscous dissipation. The solution will be assumed to be
Since is real, it is easy to verify that Since the expected vortex structure has the symmetry , we have . Upon substitution, an infinite sequence of differential equation will be obtained which are coupled non-linearly. To derive the following equations, Cauchy product rule will be used. The equations are
The boundary conditions
and the corresponding symmetry condition is enough to solve the problem. It can be shown that non-trivial solution exist only when On solving this equation numerically, it is verified that keeping first 7 to 8 terms suffice to produce accurate results. The solution when is was already discovered by Craik and Criminale in 1986.
See also
Sullivan vortex
References
Flow regimes
Vortices | Kerr–Dold vortex | [
"Chemistry",
"Mathematics"
] | 431 | [
"Dynamical systems",
"Flow regimes",
"Vortices",
"Fluid dynamics"
] |
59,414,354 | https://en.wikipedia.org/wiki/Belarusian%20Federation%20of%20Air%20Sports | The Вelarusian Federation of Air Sports (BFAS; ) is a non-profit organization and a member of the Fédération Aéronautique Internationale (FAI).
The FAI suspended Belarus due to the 2022 Russian invasion of Ukraine, as a result of which pilots from Belarus will not be able to compete in any FAI-sanctioned event in the 13 FAI air sports disciplines, including paragliding, hang gliding. and paramotoring.
As of 14 May 2018 BFAS had 265 individual members.
The Вelarusian Federation of Air Sports is the national governing and coordinating body of air sport and recreational flying. The BFAS was the issuer of FAI sporting licences in Belarus.
The Вelarusian Federation of Air Sports organized the 2018 World Helicopter Championship in July 2018 near Minsk, Belarus. The BFAS also organized the first Belarusian round-the-world flight from 18 August to 15 September 2018.
References
External links
Official website of the Вelarusian Federation of Air Sports
Aviation
Fédération Aéronautique Internationale | Belarusian Federation of Air Sports | [
"Engineering"
] | 207 | [
"Fédération Aéronautique Internationale",
"Aeronautics organizations"
] |
59,414,827 | https://en.wikipedia.org/wiki/David%20Bostock%20%28philosopher%29 | David Bostock (1936 – 29 October 2019) was a British philosopher and a Fellow of Merton College, Oxford.
Life and career
Bostock was one of four children of Edward and Alice Bostock.
He was educated at Amesbury School in Hindhead, Surrey, and at Charterhouse School.
He undertook his National Service (1955-57), serving as a 2nd Lieutenant in the Surrey Regiment.
Having read Literae Humaniores at St John's College, Oxford, and after stipendiary posts at Leicester University (1963), the Australian National University at Canberra (1964) and Harvard University (1967), Bostock served as a Fellow and Tutor in philosophy at Merton College, Oxford between 1968 and his retirement in 2004.
Bostock was subsequently an Emeritus Fellow of Merton College until his death on 29 October 2019.
Works
Bostock wrote extensively on a range of philosophical issues, with particular focus on ancient philosophy. His publications included:
Logic and Arithmetic Vol 1 (Oxford, Clarendon Press, 1974)
Logic and Arithmetic Vol 2 (Oxford, Clarendon Press, 1979)
Plato's Phaedo (Oxford, Clarendon Press, 1986)
Plato's Theaetetus (Oxford, Clarendon Press, 1988)
Aristotle's Metaphysics: Books Z and H (Oxford, Clarendon Press, 1994)
Introduction and notes in Aristotle's Aristotle's Physics (translated by Robin Waterfield) (Oxford, Oxford University Press, 1996)
Intermediate Logic (Oxford, Clarendon Press, 1997),
Aristotle's Ethics (New York, Oxford University Press, 2000)
On Motivating Higher-Order Logic, in Studies in the Philosophy of Logic and Knowledge (ed. Baldwin & Smiley, Oxford University Press, 2004)
"The Interpretation of Plato's Crito" in Plato’s Euthyphro, Apology, and Crito (ed. Kamtekar; Bowman & Littlefield, 2005)
Space, Time, Matter, and Form: Essays on Aristotle's Physics (Oxford, Clarendon Press, 2006)
Philosophy of Mathematics: An Introduction (Chichester, Wiley-Blackwell, 2009)
Aristotle's Philosophy of Mathematics, in The Oxford Handbook of Aristotle (ed. Shields; Oxford, Oxford University Press, 2012)
Russell's Logical Atomism (Oxford, Oxford University Press, 2012)
Family
In 1961 Bostock married, first, Jenny Lawton (died 1996), by whom he had two children, Timothy and Penelope.
In 2002 he married, secondly, Rosanne, the daughter of Colonel Atherton George ffolliott Powell.
Reputation
Following Bostock's death, a contemporary philosopher wrote of him:
His philosophical breadth was great, and his work was always characterised by clarity and precision. It was presented in a way that compelled the reader's interest – very often the reader's consent as well … he continued to think about philosophical issues until perhaps a year before he died. Then he decided that he had not read enough literature, and undertook a programme of reading all the books on his bookshelves, in the order in which they happened to have been placed.
References
1936 births
English philosophers
20th-century British philosophers
21st-century British philosophers
Aristotelian philosophers
British scholars of ancient Greek philosophy
Philosophers of mathematics
Alumni of St John's College, Oxford
Fellows of Merton College, Oxford
People educated at Charterhouse School
2019 deaths | David Bostock (philosopher) | [
"Mathematics"
] | 684 | [
"Philosophers of mathematics"
] |
51,563,020 | https://en.wikipedia.org/wiki/NGC%20199 | NGC 199 is a lenticular galaxy located in the constellation Pisces. It was discovered on September 24, 1862, by Heinrich Louis d'Arrest.
See also
Lenticular galaxy
List of NGC objects (1–1000)
Pisces (constellation)
References
External links
SEDS
0199
0415
+00-02-111
Lenticular galaxies
Pisces (constellation)
2382
Astronomical objects discovered in 1862 | NGC 199 | [
"Astronomy"
] | 85 | [
"Pisces (constellation)",
"Constellations"
] |
51,563,063 | https://en.wikipedia.org/wiki/NGC%20200 | NGC 200 is a spiral galaxy located in the constellation Pisces. It was discovered on December 25, 1790 by William Herschel.
See also
Spiral galaxy
List of NGC objects (1–1000)
Pisces (constellation)
References
External links
SEDS
0200
2387
Barred spiral galaxies
Pisces (constellation)
Astronomical objects discovered in 1790
Discoveries by William Herschel | NGC 200 | [
"Astronomy"
] | 76 | [
"Pisces (constellation)",
"Constellations"
] |
51,563,546 | https://en.wikipedia.org/wiki/Avant%20Stellar | The Avant Stellar is a mechanical keyboard that was produced by Creative Vision Technologies Inc (CVT). It was the successor to the popular and successful OmniKey keyboard by Northgate Computers, and was regarded as being very similar to the OmniKey Plus. It is no longer in production.
References
Footnotes
Sources
Further reading
External links
Definition at the PC Magazine Encyclopedia
Computer keyboard models | Avant Stellar | [
"Technology"
] | 78 | [
"Computing stubs",
"Computer hardware stubs"
] |
51,564,601 | https://en.wikipedia.org/wiki/Microbial%20synergy | Microbial synergy is a phenomenon in which aerobic and anaerobic microbes support each other's growth and proliferation. In this process aerobes invade and destroy host tissues, reduce tissue oxygen concentration and redox potential, thus creating favorable conditions for anaerobic growth and proliferation. Anaerobes grow and produce short chain fatty acids such as butyric acid, propionic acid. These short chain fatty acids inhibit phagocytosis of aerobes. Thus aerobes grow, proliferate and destroy more tissues. Microbial synergy complicates and delays the healing of surgical and other chronic wounds or ulcers such as diabetic foot ulcers, venous ulcers, pressure ulcers etc. Microbial synergy also helps with eliminating oxygen redox. This allows the growth of organisms without the effects of oxygen reacting negatively. As a result, Microbial growth increases because other organisms can grow in the absence of Oxygen redox.
References
Rotstein, O. D., T. L. Pruett, and R. L. Simmons. "Mechanisms of Microbial Synergy in Polymicrobial Surgical Infections." Reviews of Infectious Diseases. U.S. National Library of Medicine, n.d. Web. 19 Apr. 2017.
Microbial growth and nutrition
Microbiology | Microbial synergy | [
"Chemistry",
"Biology"
] | 272 | [
"Microbiology",
"Microscopy"
] |
51,565,398 | https://en.wikipedia.org/wiki/Arm%20and%20hammer | The arm and hammer is a symbol consisting of a muscular arm holding a hammer. Used in ancient times as a symbol of the god Vulcan, it came to be known as a symbol of industry, for example blacksmithing and gold-beating. It has been used as a symbol by many different kinds of organizations, including banks, local government, and socialist political parties.
It has been used in heraldry, appearing in the Coat of arms of Birmingham and Seal of Wisconsin.
The similarity to the name of the industrialist Armand Hammer is not a coincidence: he was named after the symbol, as his father Julius Hammer was a supporter of socialist causes, including the Socialist Labor Party of America, with its arm-and-hammer logo.
The Arm & Hammer brand is a registered trademark of Church & Dwight, an American manufacturer of household products. According to the company, the logo originally represented Vulcan. Armand Hammer made an offer to outright purchase this company having this brand with the similarity to his name, and while this offer was refused, he eventually acquired enough stock to have a controlling interest and join the board of directors. He remained an owner until his death in 1990.
An arm-and-hammer sign can be seen in Manette Street, Soho, symbolizing the trade of gold-beating carried on there in the nineteenth century. It is referred to by Charles Dickens in A Tale of Two Cities. As of 2016, the sign there is a replica, with the original being held in the Dickens Museum.
One of the oldest visualizations of arm and hammer can be found on Svetitskhoveli Cathedral. It was completed in 1029 by the medieval Georgian architect Arsukidze, although the site itself dates back to the early fourth century.
Gallery
See also
Hammer and pick
Hammer and sickle
Fist and rose
Armand Hammer
We Can Do It!
References
External links
Symbols
Heraldic charges
Symbols of communism
Visual motifs | Arm and hammer | [
"Mathematics"
] | 382 | [
"Symbols",
"Visual motifs"
] |
51,566,149 | https://en.wikipedia.org/wiki/Journal%20of%20Medical%20Biochemistry | The Journal of Medical Biochemistry is a quarterly peer-reviewed open access medical journal covering research in medical biochemistry, clinical chemistry, and related disciplines. It was established in 1982 as Jugoslovenska medicinska biohemija, obtaining its current name in 2007. It is published by Walter de Gruyter on behalf of the Society of Medical Biochemists of Serbia.
The journal exhibited unusual levels of self-citation and its journal impact factor of 2019 was suspended from the Journal Citation Reports in 2020, a sanction which hit 34 journals in total.
Editors-in-chief
The following persons are or have been editors-in-chief of the journal:
Neda Longino (1982–1988)
Ernest Suchanek (1988–1992)
Nada Majkić-Singh (1992–present)
Abstracting and indexing
The journal is abstracted and indexed in:
References
External links
Biochemistry journals
De Gruyter academic journals
English-language journals
Open access journals
Quarterly journals
Academic journals established in 1982 | Journal of Medical Biochemistry | [
"Chemistry"
] | 202 | [
"Biochemistry stubs",
"Biochemistry journals",
"Biochemistry literature",
"Biochemistry journal stubs"
] |
51,566,791 | https://en.wikipedia.org/wiki/C18H20O3 | {{DISPLAYTITLE:C18H20O3}}
The molecular formula C18H20O3 (molar mass: 284.350 g/mol) may refer to:
Bisdehydrodoisynolic acid (BDDA)
16-Ketoestrone (16-Keto-E1)
Molecular formulas | C18H20O3 | [
"Physics",
"Chemistry"
] | 71 | [
"Molecules",
"Set index articles on molecular formulas",
"Isomerism",
"Molecular formulas",
"Matter"
] |
51,567,965 | https://en.wikipedia.org/wiki/Administrative%20data | Administrative data are collected by governments or other organizations for non-statistical reasons to provide overviews on registration, transactions, and record keeping. They evaluate part of the output of administrating a program. Border records, pensions, taxation, and vital records like births and deaths are examples of administrative data. These types of data are used to produce management information, like registration data in a cost-effective way. This enables administrative data, when turned into indicators, to show trends over time and reflect real world information. The management of this information includes the Internet, software, technology, telecommunications, databases and management systems, system development methods, information systems, etc. Managing the resources of the public sector is a complex routine. It begins with the collection of data, then goes through the hardware and software that stores, manipulates, and transforms the data. Public policies then are addressed, including organizational policies and procedures.
History
Records of land holding have been used to administer taxes around the world for many centuries. In the nineteenth century international institutions for cooperation was established, such as the International Statistical Institute.
In recent decades administrative data on individuals and organization are increasingly computerized and systematic and therefore more feasibly usable for statistics, although they do not come from random samples. Using the reporting tools of routine reports, audit trails, and computer programming to cross examine databases, administrative data are increasingly used for research.
The appeal of administrative data is its ready availability, low cost, and the fact that it can span over multiple years. The government produces this kind of data because it provides a historical insight and is not invasive to the population. These data record individuals who may not respond to surveys which allows the administrative system to retain more complete records. The information that the census can provide the administrative system is limited financially and is subject to time constraints which is why administrative data can be valuable, especially when linked.
Open and linked administrative data
Open administrative data allows transparency, participation, efficiency, and economic innovation. Linked administrative data allows for the creation of large data-sets and has become a vital tool for central and local governments conducting research. By linking sections of data individually, the online web of administrative data-sets are built. For example, opening public sector data in Europe increased users 1000%. This 2011 study covered 21 open data projects in 10 countries with marginal cost operations. The Open Data Ottawa program was launched in 2010 in order to engage citizens, create transparency, reduce costs, and promote collaboration with the public. Administrative data is sought after by open data enthusiasts partly because the data has been already collected and can be reused with minimal additional cost. These data are brought up to date regularly and relay real time data as they are collected consistently.
The Justice Data Lab (JDL) established in the UK by the Ministry of Justice proposed how access to administrative data needs to be improved by linking administrative data to data produced by public services. The JDL case study explores how smaller organization attain access to administrative data. The study revealed that through working together with actors (VCS organizations, social enterprises, and private businesses), Government departments' engagement with users increased the volume of output. Due to this other Data Labs are anticipated to develop new data-sets and methodologies to showcase how open and linked administrative data can help a wide range of organizations. However, the cost of production and institutional technology required to conduct and store this data are not free. Concerns over open and linked data beyond government funding and the opposing outcomes have yet to be fully examined. Examination is mostly focused on creating projects for political and economic gain and less on implementation, sustainability, user ability, and ingrained politics.
Concerns
Some disadvantages of administrative data are that the information collected is not always open and is restricted to certain users. There is also a lack of control over content, for example Statistics Canada uses administrative data to enrich, replace survey data, or to increase the efficiency of statistical operations. These types of data do not have background information and sometimes have missing data. Changes in methodology can result in altercations to the data collected, for example when using these data to assess health care quality introductions of new diagnosis and advances in technology can affect the identification and recording of diagnoses on administrative claims. Issues with data protection is concern as more administrative data is becoming open data. Statistics Canada seeks to reduce privacy invasiveness of personal identifiers by having them removed for the linked file. The personal information, such as name, health number, or Social Insurance Number is then stored separately. However, access to linked files with personal identifiers is allowed in cases with authorization and have security, such as encryption, applied.
References
Big data
Statistical data
Civil registration and vital statistics | Administrative data | [
"Technology"
] | 945 | [
"Data",
"Big data",
"Statistical data"
] |
51,568,653 | https://en.wikipedia.org/wiki/Bull%20%28stock%20market%20speculator%29 | In finance, a bull is a speculator in a stock market who buys a holding in a stock in the expectation that, in the very short-term, it will rise in value, whereupon they will sell the stock to make a quick profit on the transaction. Strictly speaking, the term applies to speculators who borrow money to fund such a purchase, and are thus under great pressure to complete the transaction before the loan is repayable or the seller of the stock demands payment on settlement day for delivery of the bargain. If the value of the stock falls contrary to their expectation, a bull suffers a loss, frequently very large if they are trading on margin. A bull has a great incentive to "talk-up" the value of their stock or to manipulate the market of their stock, for example by spreading false rumors, to procure a buyer or to cause a temporary price increase which will provide them with the selling opportunity and profit they require.
A bull must be contrasted with an investor, who purchases a stock in expectation of a medium-term (5 years) or long-term increase in value due to the underlying performance of the company and its assets. The speculator who takes a directly opposite view to the bull is the bear, who speculates on a stock decreasing in value, having sold short. A bull market is a period during which stock market prices rise over a sustained period, therefore to the advantage of bulls.
History of the term
An early mention of the terms bull and bear appears in the 1769 edition of Thomas Mortimer's book Every Man his own Broker, published in London, as follows, relating to speculators operating in Jonathan's Coffee-House in Exchange Alley (the original London proto-Stock Exchange):
"A Bull is the name by which the gentlemen of 'Change Alley choose to call all persons who contract to buy any quantity of government securities, without an intention or ability to pay for it, and who consequently are obliged to sell it again, either at a profit or a loss, before the time comes when they have contracted to take it".
This refers to the former practice of stock-brokers, abolished circa 1980's in London, allowing their clients to trade on credit during a period of about two weeks, known as an account, on the completion of which all purchases and sales made during the account period had to be paid for on the settlement date. A net trading loss would result in the client having to make a cash payment to the broker.
Quasi-fraudster
In early usage the terms bull and bear were akin to naming a variety of fraudster, as is made clear by Mortimer, writing about 40 years after the scandal of the South Sea Bubble:
"Notwithstanding all the wise precautions hitherto taken, only the more palpable and glaring frauds have been entirely suppressed. The Bubbles are indeed burst, and the Race Horses of Exchange-Alley long since dead, but Bulls and Bears still subsist in their original vigour and full strength. The late Sir John Barnard, whose name ought to be ever dear to the citizens of London for his long and faithful services in parliament, did indeed make an attempt to crush those monsters and their keepers; but his scheme was rejected, on account of its leaving a clog and restraint on the buying and selling of stock".
Early example
Mortimer gives an example of a bull as follows:
"Thus a man who in March buys in the Alley £40,000 four per cent annuities 1760, for the rescounters in May, and at the same time is not worth ten pounds in the world, or, which is the same thing, has his money employed in trade, and cannot really take the annuities so contracted for, is a Bull, till such time as he can discharge himself of his heavy burden by selling it to another person, and so adjusting his account, which, if the whole house be Bulls, he will be obliged to do at a considerable loss; and in the interim (while he is betwixt hope and fear, and is watching every opportunity to ease himself of his load on advantageous terms, and when the fatal day is approaching that he must sell, let the price be what it will) he goes lowring up and down the house, and from office to office; and if he is asked a civil question, he answers with a surly look, and by his dejected, gloomy aspect and moroseness, he not badly represents the animal he is named after".
Bull market
Prices in financial markets rise and fall. A bull market is a market condition in which prices are rising.
This is the opposite of a bear market in which prices are declining.
In the case of the stock market, a bull market occurs when major stock indices such as the S&P 500 and the Dow rise at least 20% and continue to rise.
A bull market can last for months or even years.
Some common features of bull markets:
Investors are optimistic, or optimistic about stock prices.
Stocks go up even when there is negative news about the economy or a particular stock.
Growth is broad-based, and most stocks go up even if the company is doing poorly.
The company's revenues are generally on the rise.
The economy is thriving. Measures for this include quarterly growth in gross domestic product (GDP) and falling unemployment.
Interest rates are not rising in a way that is seen as a threat to the market rally.
Sculptures of stock-market bulls
Several bronze statues of bulls representing positive investor sentiment exist near the locations of several stock markets or brokerage houses, for example:
Charging Bull, a bronze statue by Arturo Di Modica at Bowling Green, Manhattan, New York City
"Bulle und Bär sculptures by Norbert Marten in Viersen, Germany
Sofia stock exchange, Bulgaria
Frankfurt stock exchange, Germany
Islamabad stock exchange, Pakistan
Bombay Stock Exchange, India
Amsterdam stock exchange (Beursplein 5), Netherlands
Sources
Mortimer, Thomas, Every Man his own Broker, or, A Guide to Exchange-Alley'', 7th Edition, London, 1879
Stock market, bull stock market, "every stock is lower", 9th edition, Banglore, India, 2022
References
Financial markets
Financial economics
Metaphors referring to cattle
Investment
Behavioral finance
Capitalism
Bulls | Bull (stock market speculator) | [
"Biology"
] | 1,275 | [
"Behavioral finance",
"Behavior",
"Human behavior"
] |
51,568,780 | https://en.wikipedia.org/wiki/Sex%20determination%20in%20Silene | Silene is a flowering plant genus that has evolved a dioecious reproductive system. This is made possible through heteromorphic sex chromosomes expressed as XY. Silene recently evolved sex chromosomes 5-10 million years ago and are widely used by geneticists and biologists to study the mechanisms of sex determination since they are one of only 39 species across 14 families of angiosperm that possess sex-determining genes. Silene are studied because of their ability to produce offspring with a plethora of reproductive systems. The common inference drawn from such studies is that the sex of the offspring is determined by the Y chromosome.
Evolution of sex chromosomes
Biologists have found that sex chromosomes in plants originated from pairs of autosomes. As these chromosomes diverge from their autosomal ancestor and from each other as a homologous pair, they have the potential to increase or decrease in size due to mutation and recombination. In the case of Silene, the pair of automsomal chromosomes are transformed into heteromorphic sex-determining chromosomes expressed as XY. It is important to recognize that not all species of Silene have this sex determination system. A few, such as S. colpophylla, possess homomorphic sex chromosomes.
Plants with sex-determining chromosomes, like Silene, can develop uni-sexual reproductive structures because of the loss and gain of sex-determining genes. Mutations can cause female sterility, male sterility, or adverse combinations of genes that can lead to monoecy, gynodioecy, and dioecy.
Species of Silene with different reproductive systems
The mechanisms involved in the sex determination of Silene are complex and can lead to various reproductive systems among the offspring. The table below provides only a few examples of these possible systems. Those which are most commonly found within this genus are hermaphroditism (monoecious plant with both staminate and pistillate), dioecy (male and female reproductive systems found in separate morphs), and gynodioecy (existence of female and hermaphroditic reproductive systems among the individuals of the population).
Sexual systems vary across species most silene species are hermaphroditic representing 58.2% of silene species, 14.3% are dioecious, 13.3% gynodioecious, and 12.2% being both gynodioecious and gynomonoecious. Trioecy, andromonoecy, and gynomonoecy have also been reported but are extremely rare.
Genetics
Out of 300,000 species of angiosperm, Silene are among the 5 to 10 percent whose individual offspring can be of different sexes. Hetermorphic sex-determining chromosomes are very infrequent in plant genera; some notable examples that possess them, other than Silene, are Rumex, Humulus, and Cannabis.
All species of Silene that are diploid possess the same number of chromosomes (n=12); males possess sex-determining Y chromosomes that are much larger than the X chromosomes. Recombination generally occurs only when two X chromosomes (XX) pair during female meiosis. Contrastingly, recombination is suppressed across most of the Y chromosomes during pairing in male meiosis (XY). When recombination does occur in XY chromosomes, it is confined to the tips of the chromosome, leaving most of the genetic material in the Y chromosome intact.
Importance of Y-chromosome
Several studies concentrated on Silene latifolia have shown a correlation between loci on the Y chromosome and the sex that is expressed phenotypically in the flower. Two of these sex-linked genes "promote maleness" (male fertility and male promotion) and one of them codes for female suppression. Therefore, the Y chromosome carries three dominant genes that determine the sexual expression in a Silene offspring. If there are deletions and mutations in the Y chromosome during reproduction, then different sex-linked genes are lost. The different combinations of possible sex-related genes that an individual Silene can have in one Y chromosome are what creates the rich variation of sexual phenotypes throughout this genus.
Sexual expression
The system for determining sex in Silene latifolia is close to that found in humans because in both cases the Y chromosome determines what reproductive mechanisms will be expressed in the offspring. They differ because there are multiple sex determining genes on the Y chromosome of S. latifolia, while in humans the presence or absence of the Y chromosome strictly determines whether the offspring is male or female.
Different combinations of the genes present in a Silene Y chromosome affect the sexual expression in the organism. For example, there are two genetic variations that can lead to male sterility in S. latifolia: if it possesses two Y chromosomes (YY) or if the Y chromosome possesses the female suppression and male promoting genes. Silene are also susceptible to a type of sexually transmitted infection that causes sterility. Another possible combination includes the presence of all three sex-linked genes (male suppressing, female suppressing, and male promoting) which produce virile male offspring. The flower is hermaphrodite when both male promoting and male fertility genes are present. Lastly, Y chromosomes carrying both female suppression and male fertility genes creates an asexual organism.
See also
Dioecy
Gynodioecy
Sexually transmitted infection in Silene latifolia
References
Silene
S | Sex determination in Silene | [
"Biology"
] | 1,130 | [
"Sex-determination systems",
"Sex"
] |
51,569,236 | https://en.wikipedia.org/wiki/HD%20164922%20c | HD 164922 c is an exoplanet orbiting the star HD 164922 about 72 light-years from Earth in the constellation Hercules. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
Characteristics
Mass, radius and temperature
HD 164922 c is a mini-Neptune, an exoplanet that has a radius and mass in between that of a super-Earth and the planet Neptune with no solid surface. It has a temperature of . It has an estimated mass of around 12.9 , and a potential radius of around 3.5 based on its similar mass to Neptune.
Host star
The planet orbits a (G-type) star named HD 164922. The star has a mass of 0.87 and a radius of around 0.99 . It has a temperature of 5293 K and is 13.4 billion years old. In comparison, the Sun is about 4.6 billion years old and has a temperature of 5778 K. The star is metal-rich, with a metallicity ([Fe/H]) of 0.16, or 144% the solar amount. This is particularly odd for a star as old as HD 164922. Its luminosity () is 70% of the solar luminosity.
The star's apparent magnitude, or how bright it appears from Earth's perspective, is 7.01. Therefore, HD 164922 is too dim to be seen with the naked eye, but can be viewed using good binoculars.
Orbit
HD 164922 c orbits its star every 75 days at a distance of 0.335 AU (close to Mercury's orbital distance from the Sun, which is 0.38 AU). It receives more than 6 times as much sunlight as the Earth does from the Sun.
Discovery
The search for HD 164922 c started when its host star was chosen an ideal target for a planet search using the radial velocity method (in which the gravitational pull of a planet on its star is measured by observing the resulting Doppler shift), as stellar activity would not overly mask or mimic Doppler spectroscopy measurements. It was also confirmed that HD 164922 is neither a binary star nor a quickly rotating star, common false positives when searching for transiting planets. Analysis of the resulting data found that the radial velocity variations most likely indicated the existence of a planet. The net result was an estimate of a 12.9 planetary companion orbiting the star at a distance of 0.33 AU with an eccentricity of 0.07.
The discovery of HD 164922 c was reported in the online archive arXiv on June 30, 2016.
See also
List of exoplanets discovered in 2016
References
Exoplanets discovered in 2016
Hercules (constellation)
Exoplanets detected by radial velocity | HD 164922 c | [
"Astronomy"
] | 586 | [
"Hercules (constellation)",
"Constellations"
] |
51,570,938 | https://en.wikipedia.org/wiki/38%20Virginis%20b | 38 Virginis b is a super-Jupiter exoplanet orbiting within the habitable zone of the star 38 Virginis about 108.5 light-years (33.26 parsecs) from Earth in the constellation Virgo. The exoplanet was found by using the radial velocity method, from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star.
Characteristics
Mass
38 Virginis b is a super-Jupiter, an exoplanet that has a mass larger than that of the planet Jupiter. It has a minimum mass of 4.51 .
Host star
The planet orbits a (F-type) star named 38 Virginis. The star has a mass of 1.18 and a radius of around 1.46 . It has a temperature of 6557 K and is about 1.9 billion years old. In comparison, the Sun is about 4.6 billion years old and has a temperature of 5778 K. The star is metal-rich, with a metallicity ([Fe/H]) of 0.16, or 117% the solar amount. Its luminosity () is 3.48 times that of the Sun.
The star's apparent magnitude, or how bright it appears from Earth's perspective, is 6.11. Therefore, 38 Virginis is on the edge of not being visible to the naked eye, but it can be clearly spotted with binoculars.
Orbit and habitability
38 Virginis b orbits its star every 825 days at a semi-major axis of 1.82 AU (this separation is comparable to Mars's semi-major axis, which is 1.53 AU). It likely receives as much sunlight as the Earth does from the Sun, due to its equilibrium temperature (assuming an albedo of 0.3) being only 3 degrees higher than that of Earth. Since 38 Virginis b is almost a gas giant, the habitability is instead considered for its hypothetical exomoons.
Discovery
The search for 38 Virginis b started when its host star was chosen an ideal target for a planet search using the radial velocity method (in which the gravitational pull of a planet on its star is measured by observing the resulting Doppler shift), as stellar activity would not overly mask or mimic Doppler spectroscopy measurements. It was also confirmed that 38 Virginis is neither a binary star nor a quickly rotating star, common false positives when searching for transiting planets. Analysis of the resulting data found that the radial velocity variations most likely indicated the existence of a planet. The net result was an estimate of a 4.52 planetary companion orbiting the star at a distance of 1.82 AU with an eccentricity of 0.03.
The discovery of 38 Virginis b was reported in the online archive arXiv on August 29, 2016.
Notes
References
Exoplanets discovered in 2016
Virgo (constellation)
Exoplanets detected by radial velocity
Giant planets in the habitable zone | 38 Virginis b | [
"Astronomy"
] | 609 | [
"Virgo (constellation)",
"Constellations"
] |
68,683,684 | https://en.wikipedia.org/wiki/Java%20Debug%20Wire%20Protocol | In computing, the Java Debug Wire Protocol (JDWP) is a communication protocol which is part of the Java Platform Debugger Architecture. It is used for communication between a debugger and the Java Virtual Machine, which it debugs. It allows to debug processes on a different computer. It can work over a network socket or through shared memory.
The protocol is implemented in the software library libjdwp. It can be activated using the -Xrunjdwp parameter of Java.
Metasploit includes a module for JDWP. It can exploit it using various scripts, which have functions such as injecting a Java class that executes a shell command, returns operating system details or injects an arbitrary class.
References
External links
Java Debug Wire Protocol - Java SE Documentation
Hacking the Java Debug Wire Protocol by IOActive
Patent US20110138359A1 - Modified implementation of java debug wire protocol
JDWP Misconfiguration in Container Images and K8s
Debugging
Communications protocols
Java (programming language) | Java Debug Wire Protocol | [
"Technology"
] | 229 | [
"Computer standards",
"Communications protocols"
] |
68,683,770 | https://en.wikipedia.org/wiki/Foraminifera%20test | Foraminiferal tests are the tests (or shells) of Foraminifera.
Foraminifera (forams for short) are single-celled predatory protists, mostly marine, and usually protected with shells. These shells, often called tests, can be single-chambered or have multiple interconnected chambers; the cellular machinery is contained within the shell. So important is the test to the biology of foraminifera that it provides the scientific name of the group—foraminifera, Latin for "hole bearers", referring to the pores connecting chambers of the shell in the multi-chambered species.
Foraminiferal tests are usually made of calcite, a form of calcium carbonate (), but are sometimes made of aragonite, agglutinated sediment particles, chitin, or (rarely) of silica. Other foraminifera lack tests altogether.
Over 50,000 species are recognized, both living (6,700 - 10,000) and fossil (40,000). They are usually less than 1 mm in size, but some are much larger, the largest species reaching up to 20 cm. Most forams are benthic, but about 40 extant species are planktic. The hard nature of most foraminiferal tests leads to an excellent fossil record, and they are widely researched to infer information about past climate and environments.
Background
Foraminiferal tests serve to protect the organism within. Owing to their generally hard and durable construction (compared to other protists), the tests of foraminifera are a major source of scientific knowledge about the group.
Openings in the test that allow the cytoplasm to extend outside are called apertures. The primary aperture, leading to the exterior, take many different shapes in different species, including but not limited to rounded, crescent-shaped, slit-shaped, hooded, radiate (star-shaped), dendritic (branching). Some foraminifera have "toothed", flanged, or lipped primary apertures. There may be only one primary aperture or multiple; when multiple are present, they may be clustered or equatorial. In addition to the primary aperture, many foraminifera have supplemental apertures. These may form as relict apertures (past primary apertures from an earlier growth stage) or as unique structures.
Test shape is highly variable among different foraminifera; they may be single-chambered (unilocular) or multi-chambered (multilocular). In multilocular forms, new chambers are added as the organism grows. A wide variety of test morphologies is found in both unilocular and multilocular forms, including spiraled, serial, and milioline, among others.
Many foraminifera exhibit dimorphism in their tests, with microspheric and megalospheric individuals. These names should not be taken as referring to the size of the full organism; rather, they refer to the size of the first chamber, or proloculus. Tests as fossils are known from as far back as the Ediacaran period, and many marine sediments are composed primarily of them. For instance, the limestone that makes up the pyramids of Egypt is composed almost entirely of nummulitic benthic foraminifera. It is estimated that reef foraminifera generate about 43 million tons of calcium carbonate per year.
Genetic studies have identified the naked amoeba Reticulomyxa and the peculiar xenophyophores as foraminiferans without tests. A few other amoeboids produce reticulose pseudopodia, and were formerly classified with the forams as the Granuloreticulosa, but this is no longer considered a natural group, and most are now placed among the Cercozoa.
Composition
The form and composition of their tests are the primary means by which forams are identified and classified. Most secrete calcareous tests, composed of calcium carbonate. Calcareous tests may be composed of either aragonite or calcite depending on species; among those with calcite tests, the test may contain either a high or low fraction of magnesium substitution. The test contains an organic matrix, which can sometimes be recovered from fossil samples.
Some studies suggest a high amount of homoplasy in foraminifera, and that neither agglutinated nor calcareous foraminifera form monophyletic groupings.
Soft
In some forams, the tests may be composed of organic material, typically the protein tectin. Tectin walls may have sediment particles loosely adhered onto the surface. The foram Reticulomyxa entirely lacks a test, having only a membranous cell wall. Organic-walled forams have traditionally been grouped as the "allogromiids"; however, genetic studies have found that this does not make up a natural group.
Agglutinated
Other forams have tests made from small pieces of sediment cemented together (agglutinated) by either proteins (possibly collagen-related), calcium carbonate, or Iron (III) oxide. In the past these forms were grouped together as the single-chambered "astrorhizids" and the multi-chambered textulariids. However, recent genetic studies suggest that "astrorhizids" do not make up a natural grouping, instead forming a broad base of the foram tree.
Textulariid foraminifera, unlike other living members of the globothalamea, have agglutinated tests; however, grains in these tests are cemented with a calcite cement. This calcite cement is made up of small (<100 nm) globular nanograins, similar to in other globothalameans. These tests may also have many pores, another feature uniting them with the globothalamea.
Agglutinating foraminifera may be selective regarding what particles they incorporate into their shells. Some species prefer certain sizes and types of rock particles; other species are preferential towards certain biological materials. Certain species of foraminifera are known to have preferentially agglutinated coccoliths to form their tests; others preferentially utilise echinoderm plates, diatoms, or even other foraminiferans' tests.
The foraminifera Spiculosiphon preferentially agglutinates silica sponge spicules using an organic cement; it shows strong selectivity also towards shape, utilising elongated spicules on its "stalk" and shortened ones on its "bulb". It is thought to use the spicules as both a means of elevating itself off the seabed as well as to lengthen the reach of its pseudopodia to capture prey.The agglutinated tests of xenophyophores are the largest of any foraminifera, reaching up to 20 cm in diameter. The name "xenophyophore", meaning "bearer of foreign bodies", refers to this agglutinating habit. Xenophyophores selectively uptake sediment grains between 63 and 500 μm, avoiding larger pebbles and finer silts; type of sediment seems to be a strong factor in which particles are agglutinated, as particle type preferentially includes sulfides, oxides, volcanic glass, and especially tests of smaller foraminifera. Xenophyophores 1.5 cm in diameter have been recorded completely naked, with no test whatsoever.
Calcareous
Of those foraminifera with calcareous tests, several different structures of calcite crystals are found.
Porcelaneous
Porcelaneous walls are found in the Miliolida. These consist of high-magnesium calcite organized with an ordered outer and inner calcite lining (the "extrados" and "intrados", respectively) and randomly oriented needle-shaped calcite crystals forming a thick center layer (the "porcelain"). An organic inner lining is also present. The external surface may have a pitted structure, but it is not perforated by holes. "Cornuspirid" miliolids apparently lack any extrados.
Monocrystalline
A "monocrystalline" test structure has traditionally been described for the Spirillinida. However, these tests remain poorly understood and poorly described. Some supposed "monocrystalline" spirillinids have been found to actually have tests consisting of a mosaic of very small crystals when observed with scanning electron microscope. SEM observation of Patellina sp. suggests that a truly monocrystalline test may indeed be present, with apparent cleavage faces.
Fibre bundles
Lagenid tests consist of "fibre bundles" that can reach tens of micrometres long; each "bundle" is formed from a single calcite crystal, is triangular in cross-section, and has a pore in the centre (thought to be an artefact of test deposition). There is also an internal organic layer, attached to the "cone" structure of the fibre bundles. As the crystalline structure varies significantly from that of other calcareous foraminifera, it is thought to represent a separate evolution of the calcareous test. The exact mineralisation process of lagenids remains unclear.
Hyaline
Rotaliid tests are described as "hyaline". They are formed from low-to-high-magnesium calcite "nanograins" positioned with their C-axes perpendicular to the external surface of the test. Further, these nanograins can have higher-level structure, such as rows, columns, or bundles. The test wall is characteristically bilamellar (two-layered) and perforated throughout with small pores. The outer calcite layer of the test wall is referred to as the "outer lamina" while the inner calcite layer is referred to as the "inner lining"; this should not be confused with the organic inner lining beneath the test. Sandwiched between the outer lamina and the inner lining is the "median layer", a protein layer that separates the two. The median layer is quite variable; depending on the species it may be well-defined while in others it is not sharply delineated. Some genera may contain sediment particles within the median layer.
The now-extinct Fusulinids have traditionally been considered unique in having tests of homogenous microgranular crystals with no preferred orientation and almost no cement. However, a 2017 study found that the supposed microgranular structure was actually the result of diagenetic alteration of the fossils, and that unaltered fusulinid tests instead had a hyaline structure. This suggests that the group is affiliated with the Globothalamea.
Robertinids have aragonitic tests with perforations; these are similar to the tests of rotaliids in that they are formed from nanograins, however, they differ in composition and in having well-organised columnar domains. As the earliest planktonic forams had aragonitic tests, it has been suggested that this may represent a separate evolution of a planktonic lifestyle within the Robertinida, rather than being close relatives of Globigerinans.
Hyaline aragonitic tests are also present in the Involutinida.
Spicules
The Carterinids, including the genera Carterina and Zaninettia, have a unique crystalline structure of the test which long complicated their classification. The test in this genus consists of spicules of low-magnesium calcite, bound together with an organic matrix and containing "blebs" of organic matter; this led some researchers to conclude that the test must be agglutinated. However, life studies have failed to find agglutination, and in fact the genus has been discovered on artificial substrate where sediment particles do not accumulate. A 2014 genetic study found carterinids to be an independent lineage within the Globothalamea, and supported the idea of the spicules being secreted as spicule shape differed consistently between specimens of Carterina and Zaninettia collected from the same locality (ovoid in Carterina, rounded-rectangular in Zaninettia).
Silicate
One genus, Miliamellus, has a non-perforated test made of opaline silica. It is similar in shape and structure to the porcelanous tests of typical miliolids; the test consists of an internal and external organic layer, as well as a middle silica layer made of elongate rods. This silica layer is further divided into outer, middle, and inner subunits; the outer and inner subunits each are approximately 0.2μm thick and consist of subparallel sheets of silica rods with their long axes parallel to the test surface. The middle subunit is approximately 18μm in thickness and consists of a three-dimensional lattice of silica rods with no organic component in the open space. The ultrastructure differs from that of miliolids in that the rods are over twice as long and twice as thick on average, in that the rods of Miliamellus are hollow rather than solid, and of course in having a silica test rather than calcite.
Test wall construction
When a secreted test is present, walls of foraminiferal tests may be either nonlamellar or lamellar.
Nonlamellar walls are found in some foraminifera, such as Carterinida, Spirillinida, and Miliolida. In these forms, the secretion of a new chamber is not associated with any further deposition over previous chambers. As such there is no associated layering of calcite layers on the test.
In foraminifera with lamellar walls, the deposition of a new chamber is accompanied by the deposition of a layer over previously-formed chambers. This layer may cover all previous chambers, or it may cover only some of them. These layers are known as secondary lamellae.
Foraminifera with lamellar walls can be further broken down into those with monolamellar walls and those with bilamellar walls. Monolamellar foraminifera secrete test walls which consist of a single layer, while those of bilamellar foraminifera are double-layered with an organic "median layer", sometimes containing sediment particles. In the case of bilamellar foraminifera, the outer layer is referred to as the "outer lamella" whilst the inner layer is referred to as the "inner lining". Monolamellar forams include the Lagenida, while bilamellar forms include the Rotaliida (including the major planktonic subgroup, the Globigerinina).
Bilamellar test walls can be further divided into those with septal flaps (a layer of test wall covering the previously-secreted septum) and those lacking septal flaps. Septal flaps are not known to be present in any foraminifera other than those with bilamellar walls.
The presence of a septal flap is often, though not always, associated with the presence of an interlocular space. As the name suggests, this is a small space located between chambers; it may be open and form part of the outer surface of the test, or it may be enclosed to form a void. The layer enclosing the void is formed from different parts of the lamellae in different genera, suggesting an independent evolution of enclosed interlocular spaces in order to strengthen the test.
References
Foraminifera
Microfossils | Foraminifera test | [
"Chemistry"
] | 3,248 | [
"Microfossils",
"Microscopy"
] |
68,684,091 | https://en.wikipedia.org/wiki/Nokia%20XR20 | The Nokia XR20 is a Nokia-branded smartphone that was manufactured by HMD Global.
The Nokia XR20 is also the last Nokia-branded smartphone that utilizes Zeiss optics due to HMD Global and Zeiss mutually parting way from the partnership.
References
External links
XR20
Phablets
Mobile phones introduced in 2021
Mobile phones with multiple rear cameras | Nokia XR20 | [
"Technology"
] | 74 | [
"Crossover devices",
"Mobile technology stubs",
"Phablets",
"Mobile phone stubs"
] |
68,684,874 | https://en.wikipedia.org/wiki/Ariane%20flight%20VA256 | Ariane flight VA256 was an Ariane 5 rocket flight that launched the James Webb Space Telescope (JWST) into space on 25 December 2021. It was 2021's final Ariane flight, its most valuable payload to date, and the Ariane mission. The launch was described by NASA as "flawless" and "perfect".
Launch configuration
Rocket
Ariane 5 is a heavy lift two-stage rocket with two solid fuel boosters. It was used in its ECA+ variant, which offers the highest payload mass capacity. The total launch mass of the vehicle is .
Payload
The only payload on the flight was the James Webb Space Telescope (JWST), a space-based observatory built by NASA and ESA. The launch is one of the European Space Agency's contributions to the project. The telescope had a launch mass of about and a design lifetime of 5 to 10 years.
Preparation
JWST Arrival in Kourou
The James Webb Space Telescope arrived at a port in Kourou in French Guiana, on 12 October 2021 where it was unloaded from the MN Colibri cargo ship and transported by truck to the space centre.
Integration incident
On 22 November 2021 an incident was reported by NASA and Arianespace that a clamp band securing the payload to the adapter was released during integration activities, causing vibrations to the telescope. After some tests were performed, a review board concluded on 24 November 2021 that no payload component was damaged, and fuelling operations could be started.
Fuelling operations
Spacecraft fuelling operations began on 25 November 2021, the fuelling system was disconnected on 3 December 2021, and verifications were concluded on 5 December 2021. The telescope's hypergolic fuel system was filled with approximately of hydrazine and of dinitrogen tetroxide, needed to reach and maintain its orbit after separation from the launch vehicle.
Final assembly
Following the rocket, which had already arrived on 29 November 2021, the telescope was moved to the final assembly building ( or BAF) on 7 December 2021. The payload was encapsulated inside the fairing on top of the rocket on 21 December 2021.
Interface communication issue
On 14 December 2021, a joint press release by NASA and Arianespace revealed that "a communication issue between the observatory and the launch vehicle system" was being addressed, further delaying the launch to no earlier than 24 December 2021.
Weather issue
Unfavorable weather forecasts for 24 December 2021 delayed the launch to Christmas Day, 25 December 2021.
Launch
The rocket was launched from the ELA-3 launch pad of the Guiana Space Centre on 25 December 2021 at 12:20 UTC (09:20 local time, 7:20 am U.S. EST). The DDO () of the launch was Jean-Luc Voyer, who concluded his shift by saying, "Go Webb!"
The launch was described by NASA as "flawless" and "perfect". A NASA systems engineer said "the efficiency or the accuracy with which Ariane put us on orbit and our accuracy and effectiveness in implementing our mid-course corrections" meant that there is "quite a bit of fuel margin ... roughly speaking, it’s around 20 years of propellant."
Orbit
The James Webb Space Telescope was injected into a transfer trajectory that took it to the second Earth-Sun Lagrange point (L).
The separation of the launch vehicle second stage and the spacecraft occurred approximately 27 minutes after liftoff. The second stage downloaded video, the last known time the telescope will be seen, of the separation and initial deployment of the solar panels. After this separation, the telescope became autonomous and began its deployment sequence. About 29 days after liftoff, it executed a maneuver placing it into a halo orbit around the L point, where it can perform its science mission. Its next five months were spent on cooling NIRCam and the Mid-Infrared Instrument down further, calibrating its mirrors while focusing on HD 84406, a bright star in the constellation Ursa Major, and testing the instruments.
See also
James Webb Space Telescope
Timeline of the James Webb Space Telescope
Launch and commissioning of the James Webb Space Telescope
Ariane launches
References
External links
James Webb Space Telescope detaches from Ariane 5 rocket
Ariane flight VA256 at Arianespace
VA256, Ariane flight
2021 in French Guiana
2021 in spaceflight
Rocket launchers
Rocket launches in 2021
James Webb Space Telescope | Ariane flight VA256 | [
"Astronomy"
] | 895 | [
"Space telescopes",
"James Webb Space Telescope"
] |
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