Glossary of the key notions in Bionics and beyond
Ponto-geniculo-occipital (PGO) waves
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Ponto-geniculo-occipital (PGO) waves → Phasic field potential waves recorded shortly before the onset of REM sleep from the pons, the lateral geniculate nucleus, and the occipital cortex. Positional isomers → ~ are constitutional isomers that differ only with respect to the point of attachment of a substituent. Positive cooperativity → Cooperativity, where the binding of one ligand increases the binding affinity at other sites. Positive logic → If logical 1 corresponds to voltage level H, then it is called positive logic. Positron emission tomography → The operation of positron emission tomography is based on that the molecules marked by positron radiating isotopes help the representation of the biochemical processes of the body. Positron emission tomography (PET) A640 → An imaging technique using radiant isotopes to visualize functional properties of the organs. Post-lingual deafness → ~ means that hearing loss is sustained after the acquisition of language, which can occur as a result of disease, trauma, or as a side-effect of a medicine. ~ is far more common than pre-lingual deafness. Post-patient collimators → Post-patient or predetector collimators are located below the patient and above the detector. Postsynaptic potential (PSP) → A ~ is a change in the membrane potential of the postsynaptic membrane near a synapse. PSPs are caused by the presynaptic neuron releasing neurotransmitters, which bind to receptors on the postsynaptic neuron. These receptors can react by opening or closing ion channels, which leads to a change in the membrane potential. Posttanslational formation of amino acids (Gla, Hyl, Hyp) → Some aminoacids (γ-carboxyglutamic acid, hydroxy-lysine, hydroxy-proline) are the product of conversion of aminoacid inside a protein: Glu→Gla, Lys→Hyl, Pro→Hyp Post-tetanic potentiation → Synaptic potentiation that follows a sustained, high frequency burst of presynaptic action potentials Post-translational peptide modifications → Modifications of amino acid residues in a protein sequence Postulate/axiom → To assume without proof to be true, real, or necessary, especially as a basis for argument Potassium → ~ is the chemical element with the symbol K, atomic number 19 Potential box → The potential box/finite potential well (finite square well) is an extension of the infinite potential well, in which a particle is confined to a box, but one which has finite potential walls. Potential energy → ~ (joule, J, after the English physicist James Prescott Joule, 1818–1889) is the energy stored in a body or in a system due to its position in a force field or due to its configuration The term “potential energy” was coined by the 19th century Scottish engineer and physicist William Rankine. Potential energy landscape → It plots the potential energy as a function of some reaction coordinates or all of the degrees of freedom. Power (Electricity) → It is the product of voltage by current. Power delay profile → It gives the intensity of a signal received through a multipath channel as a function of time delay. Power gating → ~ is a technique wherein circuit blocks that are not in use are temporarily turned off Power signal → A signal if it has finite average “energy” Power spectral density → It is a positive real function of a frequency variable associated with a stationary stochastic process. Poynting vector → The ~ represents the energy flux vector for electromagnetic energy (W/m2). It is named after its inventor (John Henry Poynting 1852–1914, english physicist). It can be derived directly from Maxwell’s equations in terms of total charge and current and the Lorentz force law. The ~ usually written as S is the direction in which energy travels in an EM wave. Ppm → Parts per million Precision → It refers to the ability of a measurement to be consistently reproduced. Predicate calculus (first order logic) → Predicates are formal statements about a closed microworld, called universe, we want to describe. Predicates represent relationships between individuums in the universe. There are certain operations defined on predicates, these and their properties together are called predicate calculus. Prediction → A method to estimate the next element, item of a timeseries Prefix/Suffix → An affix is a morpheme that is attached to a word stem to form a new word. They are bound morphemes by definition; prefixes and suffixes may be separable affixes. Affixation is, thus, the linguistic process speakers use to form new words (neologisms) by adding morphemes (affixes) at the beginning (prefixation), the middle (infixation) or the end (suffixation) of words. Prefixes → Prefix etymology in measurement
Prefrontal cortex (PFC) → The ~ (PFC) is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas, important for working memory, decision-making, and other “higher” cognitive functions. Pre-lingual deafness → ~ means that hearing loss sustained prior to the acquisition of language, which can occur for example as a result of a congenital condition. Premotor cortex → The ~ is an area of motor cortex lying within the frontal lobe of the brain. This region is critical to the sensory guidance of movement and control of proximal and trunk muscles of the body. Preprocessing and postprocessing → The transformation of the input and desired output of the training set, as well as the transformation if the in-work input and given response of the FFNN. Primary active transport → A transport process against the electrochemical gradient of a substance (“uphill transport”) which is directly coupled to ATP hydrolysis Primary alcohol → An alcohol that has one alkyl group bounded to the carbon atom with the hydroxyl group. Primary rainbow → Rainbow is an optical and meteorological phenomenon that causes a spectrum of light to appear in the sky when the Sun shines on to droplets of moisture in the Earth’s atmosphere. It takes the form of a multicoloured arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun. In the “primary rainbow” (the lowest, and also normally the brightest rainbow) the arc of a rainbow shows red on the outer (or upper) part of the arc, and violet on the inner section. Primary structure → Linear sequence of amino acids in a protein chain. Primary transport → Active transport where the energy is ensured directly by the hydrolysis of ATP Primitive streak → The structure on the embryonic plate that will establish bilateral symmetry, determine the site of gastrulation and initiate germ layer formation. Principal component analysis (PCA) → PCA is a method used to reduce the number of variables (dimensionality reduction) or to detect structure in the relationships among variables. Principal Component Analysis (PCA) → A statistical method for identifying patterns in data, and expressing the data in such a way as to highlight their similarities and differences. It is based on linear algebra, using eigenvalues, eigenvectors, orthogonal transformation and principal axis theorem, resulted in independent components, called principal components (independency is ensured, if data are normally ditributed). The process, to find these principal componentse is called ~. Also, ~ can be used to reduce the number of variables (dimensionality reduction). Principle neurons → Neurons establishing the main output of a certain brain region. Priority code → The only important thing about the priority code is the first 1, when we are proceeding from the biggest priority to the lower priority bits. We can encode 2n-1 bits to a log2n bit number. Prism → In optics, a ~ is a transparent (to the wavelengths for which they are designed) optical element with flat, polished surfaces that refract light. The exact angles between the surfaces depend on the application. A ~ can be used to break light up into its constituent spectral colors (the colors of the rainbow). Prisms can also be used to reflect light, or to split light into components with different polarizations. Probability → ~ is a number between 0 and 1. It expresses the knowledge or belief that an event will occur or has occurred. The bigger this number, the more likely that the event occur. The probability is the abstraction of the relative freqvency. The concept has an exact mathematical meaning in probability theory. Probability density function → It is a function that describes the relative likelihood for this random variable to occur at a given point Probe → The probe connects to any input on the instrument and typically has a resistor of ten times the ‘scope’s input impedance. This results in a .1 (-10X) attenuation factor, but helps to isolate the capacitive load presented by the probe cable from the signal being measured. Some probes have a switch allowing the operator to bypass the resistor when appropriate. Process function → They are functions that describe the process carrying the system from one equilibrium to another one. Such functions are heat and work. Procirality → Prociral molecule contains enantiotropic or diastereotopic group. Product (chemistry) → Materials which arise through a reaction. Program counter → Program counter is a processor register that indicates where the computer is in its instruction sequence. Progressive alignment → Constructing a succession of pairwise alignments Propagator → The propagator gives the probability amplitude for a particle to travel from one place to another in a given time, or to travel with a certain energy and momentum. Proprioception → Perception of intrinsic stimuli from muscle and tendon receptors Prosopagnosia → A disorder characterised by the inability to recognize faces, though to recognize other objects may remain intact. Prosthesis → A prosthesis is an artificial device that replaces missing body parts (e.g. leg, arm) or restores damaged sensory functions (e.g. hearing, vision). Prosthetic group → Cofactors connected by covalent bonds to the protein molecule. Protease → Enzyme that catalyzes the hydrolysis of peptide bonds Proteasome → Cylindrical proteolytic protein complex which degrades cell proteins that are marked for degradation by ubiquitination Protective Grounding → An electrical contact suitable to derive the short-circuit current into the ground in electric networks and devices. Protein → A linear polymer of amino acids. Proteins catalyse all the biochemical reactions essential for life. Protein folding → A physical process through which the protein adopts its three dimensional structure. Protein sequencing → A process in which the amino acid sequence of a protein is identified Proteinogenic amino acids → Kinds of amino acids which appear in protein molecules. We know twenty such amino acids and their derivatives. Proteolysis → The process in which one or more peptide bonds are cleaved inside a polypeptide chain by the enzymes proteases. ~ can be post-translational modification too. Proteome → All the protein molecules that are present in a cell or organism at a given time. Proteomics → The branch of science that deals with the proteome (i.e. the entire set of proteins in a cell or organism). Proton → The ~ is a subatomic particle with an electric charge of +1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The ~ particle is composed of three fundamental particles: two up quarks and one down quark. It is about 1.6–1.7 fm in diameter. Proton Sponge → ~ is the trade name of 1,8-bis(dimethylamino)naphthalene (a trademark of Sigma-Aldrich) was first prepared in 1968 by Roger Alder FRS (at the University of Bristol). This compound is a diamine in which the two dimethylamino groups are attached on the same side or peri position of a naphthalene system. Proton sponges have several very interesting properties; one is its very high basicity. (pKa ≈ 12.1) Psychophysiology → The study of the physiological basis of human and animal behaviour. Independent variable: psyhological, dependent variable: physiological. P-type doped → For the Group IV semiconductors (silicon, germanium…) the dopants are acceptors from Group III elements. Doping with Group III elements, which are missing the fourth valence electron, creates holes in the silicon lattice that are free to move. The result is an electrically conductive p-type semiconductor. P-type material → It contains an excess of valence band holes Pulsatile stimulation → Information is sent in the form of electrical pulses, which can be for example monophasic or biphasic. The number of pulses per second is given by the stimulation rate. The duration and amplitude of the pulse affects the extent of the injected current. Pulse sequence → The fMRI works by stimulating the brain with rapid magnetic pulses in an intense baseline magnetic field. The exact nature of those rapid pulses determines exactly what kind of fMRI signal you’re going to get out. Many things about those pulses are standardized, but not all, and you can use different pulse sequences to take functional images, depending on your scanner characteristics and different parameters of your experiment. EPI and spiral are two well-known functional pulse sequences; there are many others for other types of scans. Pulse wave → The ~ is created by cardiac contraction, sreading through the whole vascular system. Pulse width modulation → We represent the value of the signal by changing the width of the impulses following each other. Pulsed fluoroscopy → Fluoroscopy using non continuous but pulsed x-ray to create image. Pumps → Proteins by which the primary transport takes place. Pyramidal cell → The principle cell type of the cerebral cortex and hippocampus. Pyramidal tract → A motor pathway coursing from the cerebral cortex to the spinal cord. Named after its shape formed in the ventral surface of the medulla oblongata. Pyrazine → ~ is a heterocyclic aromatic organic compound, containing two nitrogen atoms at positions 1 and 4 of the six-member ring. (formula C4H4N2) Pyrazole → ~ is a heterocyclic aromatic organic compound, a five-membered ring with three carbon atoms and two nitrogens at positions 1 and 2. (formula C3H4N2) Pyridazine → Pyrazine is a heterocyclic aromatic organic compound, containing two nitrogen atoms at positions 1 and 2 of the six-member ring. (formula C4H4N2) Pyridine → ~ is a heterocyclic aromatic organic compound, a six-membered ring with five carbon atoms and one nitrogen. (formula C5H5N). Pyrimidine → ~ is a heterocyclic aromatic organic compound, containing two nitrogen atoms at positions 1 and 3 of the six-member ring. (formula C4H4N2) Pyrrole → ~ is a heterocyclic aromatic organic compound, a five-membered ring with four carbon atoms and one nitrogen. (formula C4H4NH) Pythagoras → Pythagoras of Samos (Ό Πυθαγόρας ό Σάμιος, c. 570–c. 495 BC) was an Ionian Greek philosopher, mathematician, and founder of the religious movement called Pythagoreanism. Pythagoras theorem → It is a relation in Euclidean geometry among the three sides of a right triangle. In any right triangle, the area of the square whose side opposite the right angle is equal to the sum of the areas of the squares whose sides are the two sides that meet at a right angle. 20. Q Q.e.d. → Q.e.d. is an initialism of the Latin phrase quod erat demonstrandum, which means “what was stated, has been demonstrated”. The abbreviation thus signals the completion of the proof. Quadratic Programming → An optimization task, where a quadratic function has to be minimized or maximized Quadruple-pulse TMS → Like dual-pulse stimulation, but with 4 pulses. Quadrupole → An elementary quadrupole can be represented as two dipoles oriented antiparallel. An electric quadrupole has zero charge and zero dipole moment at a graet distance. A spehryvally symmetric charge has no quadrupole moment. A quadrupole is one of a sequence of configurations of electric charge or current that can exist in ideal form, but it is usually just part of a multipole expansion of a more complex structure reflecting various orders of complexity. Quality of Service (QoS) → The goal of QoS is to provide guarantees on the ability of a communication network to deliver predictable results. Quantization → The values of the samples are rounded to some allowed discrete levels (referred to as quantization levels) and having a finite set of these levels they can then easily be represented by binary code words. Quantum coupling → Quantum coupling is an effect in quantum mechanics in which two or more quantum systems are bound such that a change in one of the quantum states in one of the systems will cause an instantaneous change in all of the bound systems. It is a state similar to quantum entanglement but whereas quantum entanglement can take place over long distances quantum coupling is restricted to quantum scales. Quantum efficiency → Describes the efficiency of the photon absorption that becomes useful signal. Quantum ElectroDynamics (QED) → Quantum electrodynamics is the quantum field theory of electrodynamics. In essence, it describes how light and matter interact, and is the first theory where full agreement between quantum mechanics and special relativity is achieved. ~ mathematically describes all phenomena involving electrically charged particles interacting by means of exchange of photons and represents the quantum counterpart of classical electrodynamics giving a complete account of matter and light interaction. Quantum mechanics (QM) → ~, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of the dual particle-like and wave-like behaviour and interaction of matter and energy. ~ describes the time evolution of physical systems via a mathematical structure called the wave function. The wave function encapsulates the probability that the system is to be found in a given state at a given time. ~ also allows one to calculate the effect on the system of making measurements of properties of the system by defining the effect of those measurements on the wave function. Quantum physics → ~ is a branch of science that deals with discrete, indivisible units of energy called quanta as described by the Quantum Theory. There are five main ideas represented in Quantum Theory: 1. Energy is not continuous, but comes in small but discrete units. 2. The elementary particles behave both like particles and like waves. 3. The movement of these particles is inherently random. 4. It is physically impossible to know both the position and the momentum of a particle at the same time. 5. The atomic world is different from the world we live in. Quark → A ~ is an elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. There are six types of quarks, known as flavors: up, down, charm, strange, top, and bottom. Quarks have intrinsic: including electric charge, color charge, spin, and mass. Quarks are the only elementary particles to experience all four fundamental interactions (fundamental forces: electromagnetism, gravitation, strong interaction, and weak interaction, and the only known particles whose electric charges are not integer multiples of the elementary charge. For every ~ flavor there is a corresponding type of antiparticle, known as antiquark, that differs from the quark only in that some of its properties have equal magnitude but opposite sign. Quaternary structure → Subunit arrangement of proteins consisting of more than one chains. Quinones → ~ are compounds having a fully conjugated cyclic dione structure, such as that of benzoquinones, derived from aromatic compounds by conversion of an even number of number of –CH= groups into –C(=O)– groups with any necessary rearrangement of double bonds (polycyclic and heterocyclic analogues are included). 21. R Yüklə 295,25 Kb. Dostları ilə paylaş:
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