Glossary of the key notions in Bionics and beyond



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Complex reaction → Not elementary reactions. They can be divided into elementary reactions.

Compound muscle action potential (CMAP) → A general term for a potential constituted by more simple potentials originating from muscle fibres.

Compton → Arthur Holly Compton (1892–1962) American scientist, (Nobel Prize in 1927)

Computational Lithography → The ~ (CL) models the scanner, resist and etch process, and can correct for the deficiencies of the physical domain by correcting the shapes on the mask

Computed tomography (ct) → Radiography in which a three-dimensional image of a body structure is constructed by computer from a series of plane cross-sectional images made along an axis

Computer measuring systems → Personal computer can control single instruments via some kind of serial or parallel interface

Concentration → ~ is an expression for the composition ratio: a quantity expressing the volume-related composition of a component of a combination, mixture or solution.

Concentration cell → two electrically connected metals are in contact with their respective metal ions in solution

Concentric contraction → the muscle shortens during contraction (the exerted force is enough to beat the resistance originating from material features or external load)

Concerted reaction → A single-step reaction through which reactants are directly transformed into products (without involvement of any intermediates), by changing two or more bonds.

Conditioning → Inducing behavioral responses with irrelevant stimuli by previous association of the irrelevant and the relevant stimuli of the behaviour.

Conductance → Electrical ~ is the reciprocal of resistance.

Conduction band → The ~ is the range of electron energies, higher than that of the valence band, sufficient to free an electron from binding with its individual atom and allow it to move freely within the atomic lattice of the material. Electrons within the ~ are mobile charge carriers in solids, responsible for conduction of electric currents in metals and other good electrical conductors.

Conduction current → A current due to a flow of conduction electrons through a body. In a conductor, electric current can flow freely. Metals typify conductors. Conductor implies that the outer electrons of the atoms are loosely bound and free to move through the material.

Conduction time → The time needed for an action potential to propagate from point A to point B. The term is used during the calculation of nerve conduction velocity.

Conductive hearing loss → ~ is a hearing disorder which developes when some problem in the outer or middle ear prevents sound from being conducted properly. It can be caused by excessive earwax, ear infections, tympanic membrane perforation, otosclerosis or tumours.

Conductivity → Electrical ~ (σ or κ, S·m−1) is the reciprocal quantity of resistivity, and measures a material’s ability to conduct an electric current.

Cones → Photoreceptor cells in the retina that function best in relatively bright light. ~ are about 100 times less sensitive to light than the rods, but allow the perception of color. They are also able to perceive finer detail and more rapid changes in images, because their response times to stimuli are faster than those of rods. Humans usually have three kinds of ~, which have different response curves and thus respond to variation in color in different ways.

Confidence interval → It gives an estimated range of values which is likely to include an unknown population parameter, the estimated range being calculated from a given set of sample data.

Configuration → A particular spatial arrangement of atoms, usually disregarding the rotation around the single bonds.

Configuration space → The ~ is the space of possible positions that a physical system may attain, possibly subject to external constraints. The ~ of a typical system has the structure of a manifold; for this reason it is also called the configuration manifold.

Configurational (pyramidal) inversion → Pyramidal inversion is a polytopal rearrangement in which the change in bond directions to a three-coordinate central atom having a pyramidal arrangement of bonds (tripodal arrangement) causes the central atom (apex of the pyramid) to appear to move to an equivalent position on the other side of the base of the pyramid. If the three ligands to the central atom are different pyramidal inversion interconverts enantiomers.

Conformation → An arrangement of an organic molecule in space of which substituent groups can assume different positions around single bonds

Conformational selection → A model for substrate binding where the substrate selectively bind - as it were choose - the appropriate enzyme conformation from a preexisted conformational pool.

Conjugate acid–base pairs → The Brønsted acid BH+ formed on protonation of a base B is called the conjugate acid of B, and B is the conjugate base of BH+. The conjugate acid always carries one unit of positive charge more than the base, but the absolute charges of the species are immaterial to the definition.

Conjunctive name → ~ is a name for assemblies of functionalized acyclic parent hydrides and cyclic systems implying the loss of an appropriate number of hydrogen atoms from each.

Conjunctive normal form → A function consisting of the AND connection of disjunctive terms, so called max terms. It is also customary to call it maxterm form, or the product of sums, or product-sum, or the product of maxterms.

Connexon → The channel, which connects cells by the gap junction and built up from 6 connexin proteins.

Conservation of energy → The law of ˇ~ is an empirical law of physics. It states that the total amount of energy in an isolated system remains constant over time (is said to be conserved over time). A consequence of this law is that energy can neither be created nor destroyed: it can only be transformed from one state to another.

Conservative force → A ~ is a force with the property that the work done in moving a particle between two points is independent of the path taken. Equivalently, if a particle travels in a closed loop, the net work done (the sum of the force acting along the path multiplied by the distance travelled) by a ~ is zero. It is possible to define a numerical value of potential at every point in space for a conservative force. When an object moves from one location to another, the force changes the potential energy of the object by an amount that does not depend on the path taken.

Conservative force field → A force field is defined everywhere in space is called a ~ or conservative vector field if it meets any of three equivalent conditions: 1. The curl of the force vector is zero. 2. There is zero net work done by the force when moving a particle through a trajectory that starts and ends in the same place. The force can be written as the gradient of a scalar potential.

Consistency model → A ~ defines how the memory instructions may be rearranged.

Constitution → ~ defines which atoms are interconnected and the type of bonds involved in these interconnections within a molecule. Connectivity alone does not convey three-dimensional information.

Constitutional isomers → Compounds possess the same molecular formula, but the connectivity of atoms is different. (2D structures are different)

Contact potential → The ~ between two different metals (brought into contact) is caused by their different work functions, which are the energies needed to remove an electron from the metal. The work function of a metal is the difference between the energy of a free electron (with no kinetic energy) outside the metal, which we choose as the zero of energy, and the chemical potential of the conduction electrons.

Contingent negative variation (CNV) → An electric sign of sensorymotor association and expectancy in the human brain. It appears in forewarned reaction time task when after some time of a warning stimulus an imperative stimulus is given.

Continuous enzyme assay → A procedure to monitor the generation of products (or consumption of substrates) taking sequential samples from the same reaction mixture as the process goes on

Continuous function → A ~ is a function for which, intuitively, small changes in the input result in small changes in the output. Otherwise, a function is said to be “discontinuous.”

Continuous attractor network → A network whose stable states form a continuous set such as a line or higher-dimensional manifold in a high-dimensional state space.

Contraction → Muscle ~ is a mechanism during the muscle shortens due to the activation of proteins actin and myosin.

Contrast → The ~ image is rendered in terms of some statistic, like a T or F, at each voxel, and each statistic can then be assigned a particular p-value - the likelihood that such a value would occur under the null hypothesis of no real activation. Voxels with p-values smaller than the threshold are declared active; other voxels are declared inactive. P-thresholds can be manipulated to account for multiple comparisons, spatial and temporal correlation.

Control of digestive anzyme activities → Gastrointestinal proteases are synzhesized primarily in precursor form (zymogen, proenzyme) and destruction of tissues by the protease is prevented by inhibitor system

Control of synthesis of nucleotides → Since the ~ requires several ATP, its control is important. The general rule is that the and products inhibit enzyme activities at the early syntheticts steps.

Conventional (clinical) electromyography → Clinical electromyography is used as a diagnostics tool for identifying neuromuscular diseases and disorders of the motor control. Usually it is performed using concentric needle electrodes.

Convergence → When signals collected by a smaller number of neurons than the number of signal-producing neurons is.

Convolution → A ~ of functions f and g (denoted by f*g, using an asterisk or star) is defined as the integral of the product of the two functions, after one is reversed ans shifted. A ~ expresses the amount of overlap of one function g as it is shifted over the other function f.

Cooperativity → Interaction by which a conformational change induced in one subunit is tramsmitted to all others in a multimeric protein

Cooperativity (ligand binding) → In ligand binding, ~ means that the binding of a ligand in a binding site affects the binding affinity at other sites.

Coordinates → A coordinate system (Cartesian/rectangular, polar, …) is a system which uses one or more numbers - ~ -, to uniquely determine the position of a point or other geometric element in space is called a frame of reference.

Copper → ~ is a chemical element with the symbol Cu and atomic number 29. It is a metal with very high thermal and electrical conductivity.

Corner analysis → Verification of functionalty under different manufacturing and operational conditions.

Correlation → There are several different ~s. The most commnly used is the Pearson’s ~. It is a single number between -1 and 1, that describes the degree of linear relationship between two (random) variables (for example the time series of bioelectric signals). This one detects only linear dependency. If it is 1, than that linear dependency is as strong as possible. If the variables are independent, then their Pearson’s correlation coefficient is 0. In the Pearson’s ~ : the covariance is divided by the product of the standard deviations.

Correspondence principle → The ~ – formulated by Niels Bohr in 1920 – states that the behavior of systems described by the theory of quantum mechanics reproduces classical physics in the limit of large quantum numbers.

Corticobulbar neurons → Cortical upper motoneurons projecting to the lower brain stem

Cotransport → Coupled transport of more kind of substances at a time.

Cotyle → Cup shaped junction of bones in a joint.

Coulomb → Charles-Augustin de Coulomb (1736–1806) was a French physicist. He is known for developing Coulomb’s law, the definition of the electrostatic force of attraction and repulsion.

Coulomb force → The one of the most universally applicable ideas in physics: action at a distance is caused by charges, which are the sources of forces. In the case of the electric ~, the magnitude is proportional to the product of the charges, and inversely proportional to the square of the distance between them. Like all forces, it is a vector quantity.

Coulomb gauge → The ~ is defined by special gauge condition. It is particularly useful for “semi-classical” calculations in quantum mechanics - in which the vector potential is quantized but the Coulomb interaction is not -: the potentials can be expressed in terms of instantaneous values of the fields and densities, the ~ is said to be a complete gauge, all other gauges give a larger integral, electromagnetic radiation was first quantized in this gauge, it is not Lorentz covariant, it can provide a good approximation to the potential in a finite volume of space in which the magnetic field is uniform, the electromagnetic potentials may be expressed in their most general forms in terms of the electromagnetic fields.

Coulomb’s law → ~ describes the electrical force between two charged particles. F=(z1z2)/(Dr2) where F is the Coulombic force, z1 and z2 are the charge of the two particles, r is their distance and D is the dielectric constant of the milieu.

Coupling → ~ (or scalar coupling) between NMR active nuclei arises from the interaction of different spin states through the chemical bonds of a molecule and results in the splitting of NMR signals. These splitting patterns can be complex or simple and, likewise, can be straightforwardly interpretable or deceptive. This ~ provides detailed insight into the connectivity of atoms in a molecule.

Coupling-in-parallel → Two or more reactions which occur simultaneously as part of the catalytic mechanism of a single enzyme

Coupling-in-series → Sequence of reactions in which the product of the preceding reaction is used immediately as a substrate in the following one

Covalent bond → The result of atoms sharing electrons in order to achieve an octet in their valance shells. It is formed by the donation of an unshared pair of valence electrons on an atom (the donor) to an empty valence orbital on another atom (the acceptor).

Covariance → ~ is number, it provides a measure of the strength of linear relationship between two random variables. A normalized ~ is the Pearsons’s correlation coefficient, the ~ is in the numerator .

Covariate → Experimental factor that can take any of a continuous range of values.

Critical angle → The ~ is defined as the angle of incidence of an electromagnetic plane wave that provides an angle of refraction of 90-degrees (total internal reflection occurs). The actual value of the 1 is dependent upon the combination of materials present on each side of the boundary.

Cross layer design → It transports feedback dynamically via the layer boundaries to enable the compensation for mismatch of requirements and resources.

Cross product → Is a mathematical operation on two vectors in the three-dimensional space. It results in a vector perpendicular to both of the vectors being multiplied and normal to the plane containing them.

Crossbar → A switch connecting multiple inputs to multiple outputs in a matrix manner

Cross-correlation → ~ is a measure of similarity of two waveforms as a function of a time-lag applied to one of them

Crown ethers → ~ (crowns) are molecular entities comprising a monocyclic ligand assembly that contains three or more binding sites held together by covalent bonds and capable of binding a guest in a central (or nearly central) position. The adducts formed are sometimes known as ‘coronates’.

Crystal → A ~ or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions.

Crystal Growing → ~ transforms polycrystalline silicon into singular crystal orientation

Cuff → During measuring the blood pressure, the ~ is normally placed smoothly and snugly around an upper arm, at roughly the same vertical height as the heart while the subject is seated with the arm supported.

Cumulanes → ~ are compounds containing two or more consecutive (cumulated) double bonds.

Cumulative distribution function (cdf) → It describes the probability that a real-valued random variable X with a given probability distribution will be found at a value less than or equal to x

Curl/rot → In vector calculus, the ~ is a vector operator (3-dimensional cross product, and is reflected in the notation Ñ×, the name of symbol Ñ is nabla) that describes the infinitesimal rotation of a 3-dimensional vector field. At every point in the field, the ~ is represented by a vector. The attributes - characterizing the rotation at that point - of this vector: length/magnitude (magnitude of rotation and direction (the axis of rotation, as determined by the right-hand rule.

Current → Electric ~ (the symbol I or i was used by Ampère himself) is a flow of electric charge through a medium. This charge is carried by moving electrons in a conductor, by ions in an electrolyte, or by both ions and electrons in a plasma. Its unit is the ampere (A~C/s), which is charge flowing through some surface at the rate of one coulomb per second.

Current clamp → ~ means that the amplitude of the injected current is predetermined, and the membrane voltage is allowed to vary freely. Injection of a depolarizing current may be sufficient to generate an action potential or other active processes.

Current controled → A circuit element where the voltage on the output can be controlled by the input current.

Current density → It is defined as a vector whose magnitude is the electric current per cross-sectional area. In a material it is proportional to the conductivity and electric field in the medium.

CUST (Cluster Affinity Search Technique) → A clustering that uses a graph-based approach that relies on the concept of a clique graph

Cut-and-try experiment (trial and error method) → We do something, and when it fails, we do something else, and keep on trying till we hit upon something which works, and we adopt that method as a thumb measure in subsequent procedure. Many scientific advances are achieved with a cut-and-try approach.

Cutoff frequency → ~ applies to an edge in a low-pass, high-pass, band-pass, or band-stop characteristic – a frequency characterizing a boundary between a passband and a stopband.

Cuvette → A ~ is a laboratory glass tube by which we measure the optical characteristics of solutes.

Cyclic guanosine monophosphate (cGMP) → A cyclic nucleotide, which acts as a second messenger. It is synthetised from guanosine triphosphate.

Cyclic nucleotide-gated (CNG) ion channel → An ion channel, the function of which is regulated by cyclic nucleotides (eg. cAMP, cGMP).

Cycloaddition → A reaction in which two or more unsaturated molecules (or parts of the same molecule) combine with the formation of a cyclic adduct in which there is a net reduction of the bond multiplicity.

Cyclotron → A ~ is a type of particle accelerator.

Cyclotron → A cyclotron is a particle accelerator in which charged particles (such as protons and ions) move on a track spiral from the inside out as an effect of a magnetic field. The electric field of the alternating current accelerates the particle twice in each rotation, transferring it to an orbit of longer radius every time.

Cylindrical coordinates → ~ are a generalization of two-dimensional polar coordinates to three dimensions by superposing a height axis. The first coordinate describes the distance from the z-axis to the point and the second coordinate describes the angle from the positive xz-plane to the point. The third coordinate is the usual z-coordinate.

Cytochromes → Heme proteins, electron carriers in respiration and in other oxido-reduction reactions

Czochralski Process → Large volume single crystal growing technique

CSD (Cambridge Sturctural Database) → ~ is a crystal structure information, chemical, and bibliographic data for about 400000 organic and metal-organic compounds: www.ccdc.cam.ac.uk/products/csd/

7. D



Dale’s principle → Dale’s law states that a neuron can not excite some of its postsynaptic targets while inhibiting others.

Data compression → ~ is an area of computer science aimed at processing data in a way that they acquire less space, or they can be transmitted as quickly as possible.

Data mining → Extraction of implicit, previously unknown, and potentially useful information (patterns, relations, etc) from data

Data rate → It is measured in bit/s. It is the number of bits that are conveyed per unit of time over a wireless link

Data structure → Structural and formal arrangement of data storage.

Database search based sequencing → A process which uses prior knowledge of amino acids stored in a database, and attempts to find similarity between the spectrums

DBS (Deep brain stimulation) lead → ~ consists of four wire insulated in polyurethane with four ring shape electrodes at the tip.

DBS+A525 (Deep brain stimulation) 4system → ~ consists of three components: the lead, the extension, and the neurostimulator. 

DC (direct current) → ~ is the unidirectional flow of electric charge. The electric charge flows in a constant direction and its magnitude does not change in time.

DdNTPs (Dideoxy nucleoside triphosphates) → Special compounds used for the base specific termination of the DNA synthesis at the Sanger sequencing method.

De Broglie’s hypothesis → In his 1923 doctoral dissertation, Louis de Broglie made a bold assertion: he wondered if electons and other “particles” might exhibit wave properties. Considering Einstein’s relationship of wavelength lambda to momentum p, de Broglie proposed that this relationship would determine the wavelength of any matter. Confirmation of the deBroglie hypothesis came in the Davisson-Germer experiment.

De novo peptide sequencing → A process of assigning amino acids from the spectrum of the peptide fragment masses of the protein

Deactivation → ~ is a process of the closing of gates by membrane hyperpolarization in a voltage-gated ion channel (the opposite of activation).

Debye → ~ is a non-SI unit of electric dipole moment. It is equal to the electric dipole moment for two charges of 10^−10 franklin separated by 1 ångström, D = 10^−18 Fr cm ≈ 3.335 64 × 10^−30 C m.

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