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Hippo signaling pathway The Hippo pathway is a recently identified signaling cascade that plays an evolutionarily conserved role in organ size control by inhibiting cell proliferation, promoting apoptosis, regulating fates of stem/progenitor cells, and in some circumstances, limiting cell size. Research indicates a key... | https://en.wikipedia.org/wiki?curid=22108748 |
GHS precautionary statements Precautionary statements form part of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS). They are intended to form a set of standardized phrases giving advice about the correct handling of chemical substances and mixtures, which can be translated into differe... | https://en.wikipedia.org/wiki?curid=22116598 |
Glass transition The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous so... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Upon cooling or heating through this glass-transition range, the material also exhibits a smooth step in the thermal-expansion coefficient and in the specific heat, with the location of these effects again being dependent on the history of the material. The question of whether some phase transition und... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition (Karl Günter Sturm Microscopic-Phenomenological Model of Glass Transition I. Foundations of the model (DOI: 10.13140/RG.2.2.19831.73121) The glass transition of a liquid to a solid-like state may occur with either cooling or compression. The transition comprises a smooth increase in the viscosity of a ... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition The expansion coefficient for the glassy state is roughly equivalent to that of the crystalline solid. If slower cooling rates are used, the increased time for structural relaxation (or intermolecular rearrangement) to occur may result in a higher density glass product. Similarly, by annealing (and thu... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Time and temperature are interchangeable quantities (to some extent) when dealing with glasses, a fact often expressed in the time–temperature superposition principle. On cooling a liquid, "internal degrees of freedom successively fall out of equilibrium". However, there is a longstanding debate whethe... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition To make this definition reproducible, the cooling or heating rate must be specified. The most frequently used definition of "T" uses the energy release on heating in differential scanning calorimetry (DSC, see figure). Typically, the sample is first cooled with 10 K/min and then heated with that same s... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition If a liquid could be supercooled below its Kauzmann temperature, and it did indeed display a lower entropy than the crystal phase, the consequences would be paradoxical. This Kauzmann paradox has been the subject of much debate and many publications since it was first put forward by Walter Kauzmann in ... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition It could also be that a first order phase transition to another liquid state occurs before the Kauzmann temperature with the heat capacity of this new state being less than that obtained by extrapolation from higher temperature. Finally, Kauzmann himself resolved the entropy paradox by postulating that... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Alternatively, P, which has a valency of 5, helps to reinforce an ordered lattice, and thus increases the "T". "T" is directly proportional to bond strength, e.g. it depends on quasi-equilibrium thermodynamic parameters of the bonds e.g. on the enthalpy "H" and entropy "S" of configurons – broken bonds... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition This region is called the rubber plateau. In ironing, a fabric is heated through this transition so that the polymer chains become mobile. The weight of the iron then imposes a preferred orientation. "T" can be significantly decreased by addition of plasticizers into the polymer matrix. Smaller molecul... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Molecular motion in condensed matter can be represented by a Fourier series whose physical interpretation consists of a superposition of longitudinal and transverse waves of atomic displacement with varying directions and wavelengths. In monatomic systems, these waves are called "density fluctuations".... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Thus we see the intimate correlation between transverse acoustic phonons (or shear waves) and the onset of rigidity upon vitrification, as described by Bartenev in his mechanical description of the vitrification process. The velocities of longitudinal acoustic phonons in condensed matter are directly r... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition The relationship between these transverse waves and the mechanism of vitrification has been described by several authors who proposed that the onset of correlations between such phonons results in an orientational ordering or "freezing" of local shear stresses in glass-forming liquids, thus yielding th... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition However, if the model includes the buildup of a charge distribution between all pairs of atoms just like a chemical bond (e.g., silicon, when a band is just filled with electrons) then it should apply to solids. Thus, if the electrical conductivity is low, the mean free path of the electrons is very sh... | https://en.wikipedia.org/wiki?curid=22122416 |
Glass transition Other authors have suggested that the electronic structure yields its influence on glass formation through the directional properties of bonds. Non-crystallinity is thus favored in elements with a large number of polymorphic forms and a high degree of bonding anisotropy. Crystallization becomes more un... | https://en.wikipedia.org/wiki?curid=22122416 |
Strecker degradation The is a chemical reaction which converts an α-amino acid into an aldehyde containing the side chain, by way of an imine intermediate. It is named after Adolph Strecker, a German chemist. The original observation by Strecker involved the use of alloxan as the oxidant in the first step, followed by ... | https://en.wikipedia.org/wiki?curid=22125656 |
IMes is an abbreviation for an organic compound that is a common ligand in organometallic chemistry. It is an N-heterocyclic carbene (NHC). The compound, a white solid, is often not isolated but instead is generated upon attachment to the metal centre. First prepared by Arduengo, the heterocycle is synthesized by conde... | https://en.wikipedia.org/wiki?curid=22126226 |
GHS hazard pictograms Hazard pictograms form part of the international Globally Harmonized System of Classification and Labelling of Chemicals (GHS). Two sets of pictograms are included within the GHS: one for the labelling of containers and for workplace hazard warnings, and a second for use during the transport of da... | https://en.wikipedia.org/wiki?curid=22131077 |
Monolithic HPLC column A monolithic HPLC column, or monolithic column, is a column used in high-performance liquid chromatography (HPLC). The internal structure of the monolithic column is created in such a way that many channels form inside the column. The material inside the column which separates the channels can be... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Monoliths, in chromatographic terms, are porous rod structures characterized by mesopores and macropores. These pores provide monoliths with high permeability, a large number of channels, and a high surface area available for reactivity. The backbone of a monolithic column is composed of either a... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Monoliths also have very short diffusion distances, while also providing multiple pathways for solute dispersion. Packed particle columns have pore connectivity values of about 1.5, while monoliths have values ranging from 6 to greater than 10. This means that, in a particulate column, a given an... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Monoliths exhibit no shear forces or eddying effects. High interconnectivity of the mesopores allows for multiple avenues of convective flow through the column. Mass transport of solutes through the column is relatively unaffected by flow rate. This is completely at odds to traditional particulat... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Additionally, packed particle columns must be maintained in a solvent environment and cannot be exposed to air during or after the packing procedure. If exposed to air, the pores dry out and no longer provide adequate surface area for reactivity; the column must be repacked or discarded. Further,... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Greatly unchanged from Tswett's time until the 1940s, normal phase chromatography was performed by passing a gravity-fed solvent through small glass tubes packed with pellicular adsorbent beads. It was in the 1940s, however, that there was a great revolution in gas chromatography (GC). Although G... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Csaba Horvath led the development of modern HPLC by piecing together laboratory equipment to suit his purposes. In 1968, Picker Nuclear Company marketed the first commercially available HPLC as a “Nucleic Acid Analyzer.” The following year, the first international symposia on HPLC was held, and K... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column In order to withstand the pressure, a new field of chromatography came into being: UHPLC or UPLC- ultra high pressure liquid chromatography. The new instruments were able to endure pressures of up to , as opposed to conventional machines, which, as previously state, can hold up to . UPLC is an al... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column The Chromolith technology was licensed from Soga and Nakanishi's group at Kyoto University. The new product won the PittCon Editors’ Gold Award for Best New Product, as well as an R&D 100 Award, both in 2001. Individual monolith columns have a life cycle that generally exceeds that of its particu... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Atypical of many technologies of the '60s and '70s, the emphasis in improvements was not on “bigger and better,” but on “smaller and better”. At the same time the HPLC user-interface was improving, it was critical to be able to isolate hundreds of peptides or biomarkers from ever decreasing sampl... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Liquid chromatography was then used for the isolation of small molecules and organic compounds like amino acids, and most recently has been used in peptide and DNA research. Monolith columns have been instrumental in advancing the field of biomolecular research. In recent trade shows and internat... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column David Hage at the University of Nebraska binds ligands to monolithic supports and measures the equilibrium phenomena of binding interactions between drugs and serum proteins. A monolith-based approach at the University of Bologna, Italy, is currently in use for high-speed screening of drug candid... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column They are able to process 200L of fermentation broth on an 800mL monolith. At BIA Separations, processing time of the tomato mosaic virus decreased considerably from the standard five days of manually intensive work to equivalent purity and better recovery in only two hours with a monolith column.... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column The technology was originally developed by Tatiana Tennikova and Frantisek Svec during a collaboration between their respective institutes. The patent for these columns was acquired by BIA Separations and Ales Podgornik and Milos Barut developed the first commercially available monolith column in... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Promptly thereafter, in 2001, Merck introduced its Chromolith line of monolithic HPLC columns at analytical instrumentation trade show PittCon. Initially, says Karin Cabrera, senior scientist at Merck, the high flow rate was the selling point for the Chromolith line. Based on customer feedback, t... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Having sublicensed the technology from Merck, Phenomenex introduced its Onyx product line in January 2005. On the other side of monolith technologies are the polymerics. Unlike the inorganic silica columns, the polymer monoliths are made of an organic polymer base. Dionex, traditionally known for... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Currently, consumers may witness technology developments in the analytical sciences industry in the form of a broader array of available pharmaceutical products of higher purity, advanced forensic testing in criminal trials, better environmental monitoring, and faster returns on medical tests. In... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Pharmaceutical companies are looking for tools that will better enable them to measure and predict the efficacy of candidate drugs in shorter times and with less expensive clinical trials. To this end, nano-scale separations, highly automated HPLC equipment, and multi-dimensional chromatography h... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Today, liquid chromatographers using multi-dimensional LC can isolate compounds at the femtomole (10 mole) and attomole (10 mole) levels. After a drug has been approved by the U.S. Food and Drug Administration (FDA), the emphasis at a pharmaceutical company is on getting a product to market. This... | https://en.wikipedia.org/wiki?curid=22131699 |
Monolithic HPLC column Not only is the monolith column more economically prudent when considering the value of product processing times, but, at the same time, less media is used, representing a significant reduction in variable costs. | https://en.wikipedia.org/wiki?curid=22131699 |
Laser ablation synthesis in solution (LASiS) is a commonly used method for obtaining colloidal solution of nanoparticles in a variety of solvents. In the LASiS method, nanoparticles are produced during the condensation of a plasma plume formed by the laser ablation of a bulk metal plate dipped in a liquid solution. LAS... | https://en.wikipedia.org/wiki?curid=22132096 |
List of human hormones The following is a list of hormones found in "Homo sapiens". Spelling is not uniform for many hormones. For example, current North American and international usage is estrogen, gonadotropin, while British usage retains the Greek digraph in oestrogen and favors the earlier spelling gonadotrophin (... | https://en.wikipedia.org/wiki?curid=22134777 |
Liquid chalk The term liquid chalk refers to several different kinds of chalk: Despite the term, some forms of "liquid chalk" contain no actual chalk. can be a variation of normal chalk (see: magnesium carbonate) used to improve grip for sports, such as rock climbing, weight lifting, or gymnastics. Rock climbers use li... | https://en.wikipedia.org/wiki?curid=22146365 |
Liquid chalk The user takes a small amount into their palms, spreading the chalk onto areas that require grip. The liquid evaporates when it comes into contact with the warmth of a users hand, leaving behind chalk. Alcohol disrupts the bonds between water molecules, reducing the energy needed to cause evaporation. | https://en.wikipedia.org/wiki?curid=22146365 |
Eccentric reducer An eccentric reducer is a fitting used in piping systems between two pipes of different diameters. They are used where the diameter of the pipe on the upstream side of the fitting (i.e. where flow is coming from) is larger than the downstream side. Unlike a concentric reducer, which resembles a cone, ... | https://en.wikipedia.org/wiki?curid=22146849 |
Multislice The multislice algorithm is a method for the simulation of the elastic interaction of an electron beam with matter, including all multiple scattering effects. The method is reviewed in the book by Cowley. The algorithm is used in the simulation of high resolution Transmission electron microscopy micrographs,... | https://en.wikipedia.org/wiki?curid=22157068 |
Multislice There are two widely used simulation techniques that exist in literature: the Bloch wave method, derived from Hans Bethe's original theoretical treatment of the Davisson-Germer experiment, and the multislice method. In this paper, we will primarily focus on the multislice method for simulation of diffraction... | https://en.wikipedia.org/wiki?curid=22157068 |
Multislice They also discussed in detail the relationship of the multislice to the other formulations. Specifically, using Zassenhaus's theorem, this paper gives the mathematical path from multislice to 1. Schroedingers equation (derived from the multislice), 2. Darwin's differential equations, widely used for diffract... | https://en.wikipedia.org/wiki?curid=22157068 |
Multislice Furthermore, the multislice algorithm does not make any assumption about the periodicity of the structure and can thus be used to simulate HREM images of aperiodic systems as well. The following section will include a mathematical formulation of the algorithm. The Schrödinger equation can also be represented... | https://en.wikipedia.org/wiki?curid=22157068 |
Multislice Roar Kilaas of Lawrence Berkeley National Laboratory. It is designed to have a user-friendly user interface and has been well-maintained relative to many other codes (last update May 2013). It is available (for a fee) from here. This is a software for multislice simulation was written in FORTRAN 77 by Dr. J.... | https://en.wikipedia.org/wiki?curid=22157068 |
Multislice The code is updated quite often with new features and a user mailing list is maintained. Freely available on their website. Multi-slice image simulations for high-resolution scanning and coherent imaging transmission electron microscopy written by Dr. Juri Barthel from the Ernst Ruska-Centre at the Jülich Re... | https://en.wikipedia.org/wiki?curid=22157068 |
Rigid-band model The Rigid-Band Model (or RBM) is one of the models used to describe the behavior of metal alloys. In some cases the model is even used for non-metal alloys such as Si alloys. According to the RBM the shape of the constant energy surfaces (hence the Fermi surface as well) and curve of density of states ... | https://en.wikipedia.org/wiki?curid=22159309 |
Rigid-band model When different kind of atoms are dissolved into it, for example 10% of copper, some random lattice sites become occupied by copper atoms. Since silver has a valence of 1 and copper has a valence of 2, the alloy will now have a valence of 1.1. Most lattice sites however are still occupied by silver atom... | https://en.wikipedia.org/wiki?curid=22159309 |
Rigid-band model In spite of such fundamental difficulties, experimental and theoretical works have provided ample evidence that the concept of the Fermi surface and Brillouin zone is still valid even in concentrated crystalline alloys In an alloy of atoms A and B, an intermetallic compound super-lattice structure tend... | https://en.wikipedia.org/wiki?curid=22159309 |
Rigid-band model When the periodicity of the pure metal is destroyed by alloying, these Bloch states are no longer eigenstates and their energy becomes complex formula_9 The imaginary part Γ shows that the Bloch state in the alloy is no longer an eigenstate but scatters into other states with a lifetime of the order of... | https://en.wikipedia.org/wiki?curid=22159309 |
Rigid-band model In the case when formula_15 is constant we get meaning that the shape of the density of states will be the same, only displaced by formula_15. | https://en.wikipedia.org/wiki?curid=22159309 |
Dynamic binding (chemistry) In complexation catalysis, the term dynamic binding refers to any stabilizing interaction that is stronger at the transition state level than in the reactant-catalyst complex. Being directly related to transition state stabilization, dynamic binding is the very hearth of complexation catalys... | https://en.wikipedia.org/wiki?curid=22160206 |
Cis-regulatory module "Cis"-regulatory module (CRM) is a stretch of DNA, usually 100–1000 DNA base pairs in length, where a number of transcription factors can bind and regulate expression of nearby genes and regulate their transcription rates. They are labeled as "cis" because they are typically located on the same DN... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module However, this definition has changed to define "cis"-regulatory modules as a DNA sequence with transcription factor binding sites which are clustered into modular structures, including -but not limited to- locus control regions, promoters, enhancers, silencers, boundary control elements and other ... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module Thus gene-regulation functions (GRF) provide a unique characteristic of a cis-regulatory module (CRM), relating the concentrations of transcription factors (input) to the promoter activities (output). The challenge is to predict GRFs. This challenge still remains unsolved. In general, gene-regulat... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module Additionally, besides influence from the different logic operations, the output of a "cis"-regulatory module will also be influenced by prior events. 4) "Cis"-regulatory modules must interact with other regulatory elements. For the most part, even with the presence of functional overlap between "c... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module 0 is a web server that allows to search Cis-regulatory modules in a genome-wide manner. The program relies on the definition of strict restrictions among the Transcription Factor Binding Sites (TFBSs) that compose the module in order to decrease the false positives rate. INSECT is designed to be u... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module The possible cis-regulatory modules are then statistically analyzed and the significant combinations are graphically represented Active "cis"-regulatory modules in a genomic sequence have been difficult to identify. Problems in identification arise because often scientists find themselves with a s... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module Rheostatic response model describes cis-regulatory modules as regulators of the initiation rate of transcription of its associated gene. "Cis"-regulatory modules can regulate their target genes over large distances. Several models have been proposed to describe the way that these modules may commu... | https://en.wikipedia.org/wiki?curid=22164509 |
Cis-regulatory module During development each domain, where each domain represents a different spatial regions of the embryo, of gene expression will be under the control of different "cis"-regulatory module(s). The design of regulatory modules help in producing feedback, feed forward, and cross-regulatory loops. | https://en.wikipedia.org/wiki?curid=22164509 |
Freshwater environmental quality parameters are the natural and man-made chemical, biological and microbiological characteristics of rivers, lakes and ground-waters, the ways they are measured and the ways that they change. The values or concentrations attributed to such parameters can be used to describe the pollution... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters Filling a clean bottle with river water is a very simple task, but a single sample is only representative of that point along the river the sample was taken from and at that point in time. Understanding the chemistry of a whole river, or even a significant tributary, requires... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters In recent decades as the need to understand ground water dynamics has increased, an increasing number or monitoring bore-holes have been drilled into aquifers "see also Limnology" Lakes and ponds can be very large and support a complex eco-system in which environmental parame... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters A mixing zone may be very large and extend for many miles as in the case of the Mississippi and Missouri rivers in the United States and the River Clwyd and River Elwy in North Wales. In a mixing zone water chemistry may be very variable and can be difficult to predict. The c... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters Fast, turbulent streams expose more of the water's surface area to the air and tend to have low temperatures and thus more oxygen than slow, backwaters. Oxygen is a by-product of photosynthesis, so systems with a high abundance of aquatic algae and plants may also have high c... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters The majority of rivers on the planet and many lakes have received or are receiving inputs from human-kind's activities. In the industrialised world, many rivers have been very seriously polluted, at least during the 19th and the first half of the 20th centuries. Although in g... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters However both colour and turbidity reduce the amount of light penetrating the water and can have significant impact on algae and macrophytes. Some algae in particular are highly dependent on water with low colour and turbidity Many rivers draining high moor-lands overlain by p... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters A wide range of metals may be found in rivers from natural sources where metal ores are present in the rocks over which the river flows or in the aquifers feeding water into the river. However many rivers have an increased load of metals because of industrial activities which... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters "Microregma" starts to show a toxic reaction at concentrations as low as 0.33 mg/l Lead and silver in river waters are commonly found together and associated with lead mining. Impacts from very old mines can be very long-lived. In the River Ystwyth in Wales for example, the e... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters Significant levels of copper are unusual in rivers and where it does it occur the source is most likely to be mining activities, coal stocking, or pig farming. Rarely elevated levels may be of geological origin. Copper is acutely toxic to many freshwater organisms, especially... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters All forms of nitrogen are taken up by macrophytes and algae and elevated levels of nitrogen are often associated with overgrowths of plants or eutrophication. These can have the effect of blocking channels and inhibiting navigation. However, ecologically, the more significant... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters On warm summer days with high-bi-carbonate concentrations unexpectedly toxic conditions can be created. Phosphorus compounds are usually found as relatively insoluble phosphates in river water and, except in some exceptional circumstances, their origin is agriculture or human... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters Much of this settles very quickly and provides an important substrate for many aquatic organisms. Many salmonid fish require beds of gravel and sand in which to lay their eggs. Many other types of solids from agriculture, mining, quarrying, urban run-off and sewage may block-... | https://en.wikipedia.org/wiki?curid=22166495 |
Freshwater environmental quality parameters coli bacteria have been commonly found in recreational waters and their presence is used to indicate the presence of recent faecal contamination, but E. coli presence may not be indicative of human waste. " E. coli" are found in all warm-blooded animals. "E. coli" have also b... | https://en.wikipedia.org/wiki?curid=22166495 |
Bioceramic Bioceramics and bioglasses are ceramic materials that are biocompatible. Bioceramics are an important subset of biomaterials. Bioceramics range in biocompatibility from the ceramic oxides, which are inert in the body, to the other extreme of resorbable materials, which are eventually replaced by the body aft... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic This work inspired a new field called bioceramics. With the discovery of bioglass, interest in bioceramics grew rapidly. On April 26, 1988, the first international symposium on bioceramics was held in Kyoto, Japan. Ceramics are now commonly used in the medical fields as dental and bone implants. Surgical cer... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic Some bioceramics incorporate alumina (AlO) as their lifespan is longer than that of the patient's. The material can be used in inner ear ossicles, ocular prostheses, electrical insulation for pacemakers, catheter orifices and in numerous prototypes of implantable systems such as cardiac pumps. Aluminosilicat... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic Additionally, it has lower mechanical strength compared to bone, making highly porous implants very delicate. Since Young's modulus of ceramics is generally much higher than that of the bone tissue, the implant can cause mechanical stresses at the bone interface. Calcium phosphates usually found in biocerami... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic Other natural materials — generally of animal origin — such as bioglass and other composites feature a combination of mineral-organic composite materials such as HAP, alumina, or titanium dioxide with the biocompatible polymers (polymethylmethacrylate): PMMA, poly(L-lactic) acid: PLLA, poly(ethylene). Compos... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic The ceramic particulate reinforcement has led to the choice of more materials for implant applications that include ceramic/ceramic, ceramic/polymer, and ceramic/metal composites. Among these composites ceramic/polymer composites have been found to release toxic elements into the surrounding tissues. Metals ... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic The prospect of using these relatively low processing temperatures opens up possibilities for mineral organic combinations with improved biological properties through the addition of proteins and biologically active molecules (growth factors, antibiotics, anti-tumor agents, etc.). However, these materials ha... | https://en.wikipedia.org/wiki?curid=22183423 |
Bioceramic HA/polymer composite (HA/polyethyelene, HAPEXTM) is also commercially available for ear implants, abrasives, and plasma-sprayed coating for orthopedic and dental implants. Bioceramics have been proposed as a possible treatment for cancer. Two methods of treatment have been proposed: hyperthermia and radiothe... | https://en.wikipedia.org/wiki?curid=22183423 |
Turbulent diffusion is the transport of mass, heat, or momentum within a system due to random and chaotic time dependent motions. It occurs when turbulent fluid systems reach critical conditions in response to shear flow, which results from a combination of steep concentration gradients, density gradients, and high vel... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion There are many factors included in this modeling process, such as which level of atmosphere(s) the mixing is taking place, the stability of the environment and what type of contaminant and source is being mixed. The Eulerian and Lagrangian (discussed below) models have both been used to simulate atm... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion The Eulerian approach to turbulent diffusion focuses on an infinitesimal volume at a specific space and time in a fixed frame of reference, at which physical properties such as mass, momentum, and temperature are measured. The model is useful because Eulerian statistics are consistently measurable a... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion Fortunately there exists a closure approximation in introducing the concept of eddy diffusivity and its statistical approximations for the random concentration and velocity components from turbulent mixing. formula_13 Where K is the eddy diffusivity. Substituting into the first continuity equation a... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion The concentration of particles at a location x and time t can then be calculated by summing the probabilities of the number of particles observed as follows: formula_16 Which is then evaluated by returning to the pdf integral formula_17 Thus, this approach is used to evaluate the position and veloci... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion This model is very useful in atmospheric sciences, especially when dealing with concentrations of contaminants in air pollution that emanate from sources such as combustion stacks, rivers, or strings of automobiles on a road. Because applying mathematical equations to turbulent flow and diffusion is... | https://en.wikipedia.org/wiki?curid=22187097 |
Turbulent diffusion As technology and computer abilities are rapidly expanding, these methods will also improve greatly, and will more than likely be at the forefront of future research on modeling turbulent diffusion. Aside from these efforts, there also have been advances in fieldwork used before computers were avail... | https://en.wikipedia.org/wiki?curid=22187097 |
Psychochemical warfare involves the use of psychopharmacological agents (mind-altering drugs or chemicals) with the intention of incapacitating an adversary through the temporary induction of hallucinations or delirium. These agents have generally been considered chemical weapons and, more narrowly, constitute a specif... | https://en.wikipedia.org/wiki?curid=22191978 |
Psychochemical warfare In 1881, members of a French railway surveying expedition crossing Tuareg territory in North Africa ate dried dates that tribesmen had apparently deliberately contaminated with Egyptian henbane ("Hyoscyamus muticus", or "H. falezlez"), to devastating effect. In the 1950s, the CIA investigated LSD... | https://en.wikipedia.org/wiki?curid=22191978 |
Signorini problem The is an elastostatics problem in linear elasticity: it consists in finding the elastic equilibrium configuration of an anisotropic non-homogeneous elastic body, resting on a rigid frictionless surface and subject only to its mass forces. The name was coined by Gaetano Fichera to honour his teacher, ... | https://en.wikipedia.org/wiki?curid=22194510 |
Signorini problem During Fichera's researches on the problem, Signorini began to suffer serious health problems: nevertheless, he desired to know the answer to his question before his death. Picone, being tied by a strong friendship with Signorini, began to chase Fichera to find a solution: Fichera himself, being tied ... | https://en.wikipedia.org/wiki?curid=22194510 |
Signorini problem The problem consist in finding the displacement vector from the natural configuration formula_1 of an anisotropic non-homogeneous elastic body that lies in a subset formula_2 of the three-dimensional euclidean space whose boundary is formula_3 and whose interior normal is the vector formula_4, resting... | https://en.wikipedia.org/wiki?curid=22194510 |
Signorini problem If formula_16 is any tangent vector to the contact set formula_5, then the ambiguous boundary condition in each point of this set are expressed by the following two systems of inequalities Let's analyze their meaning: Knowing these facts, the set of conditions applies to points of the boundary of the ... | https://en.wikipedia.org/wiki?curid=22194510 |
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