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Adhesion (other)
Adhesion is the tendency of certain dissimilar molecules to cling together. Adhesion may also refer to: Biology * Adhesion (medicine), a fibrous band that forms between tissues and organs * Cell adhesion, the binding of a cell to another cell or to a surface or matrix * Focal adhesion, a type of macromolecular assembly in cell biology * Interthalamic adhesion, a band connecting the brain's two thalami * Adhesion barrier Other * Rail adhesion, a type of railway * Adhesion contract, in law * Adhesion (Politics) Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can ... See also * Adhesive * Cohesion (other) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to half the work of cleavage, W: γ = (1/2)W11. If the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion (medicine)
Adhesions are fibrous bands that form between tissues and organs, often as a result of injury during surgery. They may be thought of as internal scar tissue that connects tissues not normally connected. Pathophysiology Adhesions form as a natural part of the body's healing process after surgery in a similar way that a scar forms. The term "adhesion" is applied when the scar extends from within one tissue across to another, usually across a virtual space such as the peritoneal cavity. Adhesion formation post-surgery typically occurs when two injured surfaces are close to one another. According to the "classical paradigm" of adhesion formation, the pathogenesis starts with inflammation and activation of the coagulation system which causes fibrin deposits onto the damaged tissues. The fibrin then connects the two adjacent structures where damage of the tissues occurred. The fibrin acts like a glue to seal the injury and builds the fledgling adhesion, said at this point to be "fibr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Adhesion
Cell adhesion is the process by which cells interact and attach to neighbouring cells through specialised molecules of the cell surface. This process can occur either through direct contact between cell surfaces such as cell junctions or indirect interaction, where cells attach to surrounding extracellular matrix, a gel-like structure containing molecules released by cells into spaces between them. Cells adhesion occurs from the interactions between cell-adhesion molecules (CAMs), transmembrane proteins located on the cell surface. Cell adhesion links cells in different ways and can be involved in signal transduction for cells to detect and respond to changes in the surroundings. Other cellular processes regulated by cell adhesion include cell migration and tissue development in multicellular organisms. Alterations in cell adhesion can disrupt important cellular processes and lead to a variety of diseases, including cancer and arthritis. Cell adhesion is also essential for inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Adhesion
In cell biology, focal adhesions (also cell–matrix adhesions or FAs) are large macromolecular assemblies through which mechanical force and regulatory signals are transmitted between the extracellular matrix (ECM) and an interacting cell. More precisely, focal adhesions are the sub-cellular structures that mediate the regulatory effects (i.e., signaling events) of a cell in response to ECM adhesion. Focal adhesions serve as the mechanical linkages to the ECM, and as a biochemical signaling hub to concentrate and direct numerous signaling proteins at sites of integrin binding and clustering. Structure and function Focal adhesions are integrin-containing, multi-protein structures that form mechanical links between intracellular actin bundles and the extracellular substrate in many cell types. Focal adhesions are large, dynamic protein complexes through which the cytoskeleton of a cell connects to the ECM. They are limited to clearly defined ranges of the cell, at which the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interthalamic Adhesion
The interthalamic adhesion (also known as the intermediate mass or middle commissure) is a flattened band of tissue that connects both parts of the thalamus at their medial surfaces. The medial surfaces form the upper part of the lateral wall to the third ventricle. In humans, it is only about one centimeter long – though in females, it is about 50% larger on average. Sometimes, it is in two parts – and 20% of the time, it is absent. In other mammals, it is larger. In 1889, a Portuguese anatomist by the name of Macedo examined 215 brains, showing that male humans are approximately twice as likely to lack an interthalamic adhesion as are female humans. He also reported its absence, still reported today in about 20% of humans. Its absence is seen to be of no consequence. The interthalamic adhesion contains nerve cells and nerve fibers; a few of the latter may cross the middle line, but most of them pass toward the middle line and then curve laterally on the same side. It is s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion Barrier
An adhesion barrier is a medical implant that can be used to reduce abnormal internal scarring ( adhesions) following surgery by separating the internal tissues and organs while they heal. Surgeons have realized that proper surgical technique is crucial to reduce adhesion formation. In addition, for more than a century, adjuvants including drugs and materials such as animal membranes, gold foil, mineral oil, sheets made of rubber and Teflon, have been used to reduce the risk of adhesion formation. Nevertheless, adhesions do occur and appear to be, to some degree, an almost unavoidable consequence of abdominal and pelvic surgery. Adhesions can lead to significant post-surgical morbidity, bowel obstruction, infertility, and chronic pelvic pain or chronic abdominal pain. Surgeons and healthcare professionals developed several methods for minimizing tissue injury in order to minimize the formation of adhesions. However, even an experienced surgeon despite using advanced techniqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rail Adhesion
An adhesion railway relies on adhesion traction to move the train. Adhesion traction is the friction between the drive wheels and the steel rail. The term "adhesion railway" is used only when it is necessary to distinguish adhesion railways from railways moved by other means, such as by a stationary engine pulling on a cable attached to the cars or by railways that are moved by a pinion meshing with a rack. The friction between the wheels and rails occurs in the wheel-rail interface or contact patch. The traction force, the braking forces and the centering forces, all contribute to stable running. However, running friction increases costs by requiring higher fuel consumption and by increasing the maintenance needed to address fatigue (material) damage, wear on rail heads and on the wheel rims and rail movement from traction and braking forces. Variation of friction coefficient Traction or friction is reduced when the top of the rail is wet or frosty or contaminated with g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion Contract
A standard form contract (sometimes referred to as a ''contract of adhesion,'' a ''leonine contract'', a ''take-it-or-leave-it contract'', or a '' boilerplate contract'') is a contract between two parties, where the terms and conditions of the contract are set by one of the parties, and the other party has little or no ability to negotiate more favorable terms and is thus placed in a "take it or leave it" position. While these types of contracts are not illegal ''per se'', there exists a potential for unconscionability. In addition, in the event of an ambiguity, such ambiguity will be resolved '' contra proferentem'', i.e. against the party drafting the contract language. Theoretical issues There is much debate on a theoretical level whether, and to what extent, courts should enforce standard form contracts. On one hand, they undeniably fulfill an important role of promoting economic efficiency. Standard form contracting reduces transaction costs substantially by avoiding the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion (Politics)
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to half the work of cleavage, W: γ = (1/2)W11. If the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesive
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantages over other binding techniques such as sewing, mechanical fastenings, or welding. These include the ability to bind different materials together, the more efficient distribution of stress across a joint, the cost-effectiveness of an easily mechanized process, and greater flexibility in design. Disadvantages of adhesive use include decreased stability at high temperatures, relative weakness in bonding large objects with a small bonding surface area, and greater difficulty in separating objects during testing. Adhesives are typically organized by the method of adhesion followed by ''reactive'' or ''non-reactive'', a term which refers to whether the adhesive chemically reacts in order to harden. Alternatively, they can be organized eit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
