Glossary of the key notions in Bionics and beyond

Latency → The ~ is the time delay between the onset of a stimulus and the response it triggers. The term ~ is used for example by evoked potentials or by calculating the nerve conduction speeds.

Lateral geniculate nucleus → A part of the metathalamus, which serves as a relay nucleus within the visual pathway.

Lateral grasp → Grasp with thumb and index finger to hold smaller objects.

Lateral inhibition → The reduction of the neuronal activity in the neighbourhood of an excited neuron.

Lateral plane → A ~ is an Y-Z plane, perpendicular to the ground, which separates left from right (in standard Descartes coordinate system)

Law of mass action → A model predicting the equilibrium concentrations of reactants and products in a reversible reaction.

Laws of nature → Natural law or the law of nature has been described as a law whose content is set by nature and that therefore is universal. Natural law is often conflated with common law. It is a scientific generalization based on empirical observations of physical behaviour. Laws of nature are observable. Empirical laws are typically conclusions based on repeated scientific experiments and simple observations, and which have become accepted universally within the scientific community.

Layered Communication Approaches → ~ is a a conceptual framework of standards for communication in the network across different equipment and applications by different vendors. The network communication protocols used today have a structure based on the layered model.

Layout → Planar view of polygons representing a circuit.

LCAO (Linear Combination of Atomic Orbitals) A1279method → ~ is a quantum superposition of atomic orbitals and a technique for calculating molecular orbitals in quantum chemistry. In mathematical sense, wave functions are the basis set of functions, the basis functions, which describe the electrons of a given atom. In chemical reactions, orbital wavefunctions are modified, i.e. the electron cloud shape is changed, according to the type of atoms participating in the chemical bond.

LCAO-MO theory → ~ is a theory that describes a linear combination of atomic orbitals that produces molecular orbitals

Lead compound → In drug discovery a ~ is a chemical compound that has pharmacological or biological activity and whose chemical structure is used as a starting point for chemical modifications in order to improve potency, selectivity, or pharmacokinetic parameters.

Leakage current → Current flowing along the penetrating intracellular electrode between the intracellular and extracellular spaces.

Learning procedure → The procedure when a free parameters are tuned to perform a special task

Learning rule → Algorithm, which uploads the program of the network

Least action principle → The principle of least action – or, more accurately, the principle of stationary action – is a variational principle that, when applied to the action of a mechanical system, can be used to obtain the equations of motion for that system.

Least-square minimization algorithm → A method to approximate the solution of overdetermined equation systems. The overall solution gained from this method minimizes the sum of the squares of the errors made in solving every single equation.

Leaving (signal) → A signal is leaving if it only has 0 values for time instants greater or equal then 0.

Leksell stereotactic system → Human stereotactic apparatus based on polar coordinate system invented by Lars Leksell Swedish neurosurgeon

Leksell SurgiPlan → Computer based surgical planning system based on fusion of CT, MR and other imaging texhniques and the Leksell stereotactic apparatus

Lenard → Philipp Eduard Anton von Lenard (1862–1947), Lénárd Fülöp Eduárd Antal, was a German physicist (1905 Nobel Prize for his research on cathode rays).

Lenard – Einstein → Lénard found the energies of the emitted electrons concerning of the photoelectronic effect to be independent of the intensity of the incident radiation. In Einstein’s model, increasing the frequency, rather than the intensity, of the incident radiation would increase the average energy of the emitted electrons.

Length constant → The distance in which the 63% of the maximal action potential is reached. The greater the length constant, the farther the AP has effect.

Lennard-Jones potential → Is a model of the van der Waals interaction between two atoms. It depicts the potential energy as a function of the distance between them.

Lepton → A ~ is an elementary particle and a fundamental constituent of matter. The best known of all leptons is the electron which governs nearly all of chemistry as it is found in atoms and is directly tied to all chemical properties. Two main classes of leptons exist: charged leptons (also known as the electron-like leptons), and neutral leptons (better known as neutrinos). There are six types of leptons (electrons and electron neutrinos, muons and muon neutrinos, taus and tau neutrinos). Leptons have various intrinsic properties, including electric charge, spin, and mass. Unlike quarks however, leptons are not subject to the strong interaction, but they are subject to the other three fundamental interactions: gravitation, electromagnetism (excluding neutrinos, which are electrically neutral), and the weak interaction.

Lesion → A pathological change in the tissue, which is caused either by disease, injury or trauma.

Level Crossing Rate (LCR) → The rate at which the fieldstrength goes below the considered threshold value.

Levinthal’s paradox → It shows that it is impossible for a protein to find the native state by random search in an adequate time due to the large number of degrees of freedom.

Lewis acid base theory → A theory where acids are defined as electron pair acceptors and bases as electron pair donors

Lewis formula (Lewis structure) → ~ (or Lewis structure) is a molecular structure in which the valency electrons are shown as dots so placed between the bonded atoms that one pair of dots represents two electrons or one covalent (single) bond, e.g. A double bond is represented by two pairs of dots, etc. Dots representing non-bonded outer-shell electrons are placed adjacent to the atoms with which they are associated, but not between the atoms. Formal charges (e.g. +, −, 2+, etc.) are attached to atoms to indicate the difference between the positive nuclear charge (atomic number) and the total number of electrons (including those in the inner shells), on the formal basis that bonding electrons are shared equally between atoms they join. (Bonding pairs of electrons are usually denoted by lines, representing covalent bonds, as in line formulae.)

Leyden jar → A device used to store static electricity. It was the first capacitor invented by Pieter van Musschenbroek (1692-1761) in 1746.

Liftoff → The process is useful for patterning materials that cannot be etched without affecting underlying materials on the substrate.

Ligand → A small molecule which can bind to a bigger one, for example a receptor.

Ligand-gated carriers → Carriers opening of which depends on the binding some ligand.

Ligand-gated ion channel → Ion channel that require certain molecules attached to them in order to open.

Ligase → an enzyme which catalyzes C-C bond formation

Ligation → Joining two chemical groups by a covalent bond.

Light → Light is electromagnetic radiation. Primary properties of light are intensity, propagation direction, frequency or wavelength spectrum, and polarization, while its speed, about 3×10⁸ m/s in a vacuum, is one of the fundamental constants of nature. Light, which is emitted and absorbed in tiny “packets”, called photons, exhibits properties of both waves and particles. This property is referred to as the wave–particle duality.

Likelyhood function → Density function of outcome if obersavations are known

Limb (Neoromorph movement control) → Is an object containing different segments(links) connected to each other via joints. Joints are capable of rotating around joints.

Limited support (signal) → A signal has a limited support if there exist two time instants, say t1
Linear combination of atomic orbitals → A linear combination is a quantum superposition and a technique for calculating. In quantum mechanics, electron configurations of atoms are described as wavefunctions. In mathematical sense, these wave functions are the basis set of functions, the basis functions, which describe the electrons of a given atom. An initial assumption is that the number of molecular orbitals is equal to the number of atomic orbitals included in the linear expansion. The coefficients are the weights of the contributions of the n atomic orbitals to the molecular orbital.

Linear operator → A ~ is a mapping from one linear vector space to another (or itself), obeying two rules: additivity and homogenity

Linear phase (filter) → a filter which has a ~ characteristics

Linear polarization → Polarization (also polarisation) is a property of certain types of waves that describes the orientation of their oscillations. Electromagnetic waves exhibit polarization. By convention, the polarization of waves is described by specifying the orientation of the wave’s electric field at a point in space over one period of the oscillation. If the electric field is oriented in a single direction, we say about linear polarization.

Linear range → The part of the forward range, where the voltage-current function can be approximated linearly.

Linear separability → Two point sets are linearly separable in n-dimensional space if they can be separated by a hyperplane.

Line-of-sight (LoS) → There are no obstructions between the transmitter and receiver and the signal propagates along a straight line between the two.

Link budget → It is the accounting of all of the gains and losses in a wireless link from the transmitter, through the wireless medium to the receiver.

Lipase → A hydrolase which cleaves the ester bonds in lipids (triacylglycerol, phospholipid)

Lipid → A compound extractable from tissues with non-polar solvents

Lipid bilayer → The general structure of biological membranes. It is constituted by two layers of lipids which face to each other by their hydrophobic part while to water they face by their hydrophilic head.

Lipids → A group of organic compounds. Lipids are at least partly hydrophobic.

Lipoprotein → Multimolecular complex of protein, phospholipid and cholesterol that encloses a core composed of triacylglycerols, phospholipids and other lipids

Lipoprotein lipase → Lipase which hydrolyzes triacylglycerol and phospholipds in plasma lipoproteins (VLDL and chylomicrons)

Liquid → Liquids are composed of particles that are loosely associated and freely moving. Liquids have definite volume, but no definite shape.

Liquid-liquid Extraction/Washing → ~ method by which material is selectively transferred from one into the other phase of mixture of two immiscible solvents.

Lissauer zone → Nerve tract surrounding the tip of the posterior horn of the spinal cord

Lithography → ~ is the process of transferring an image from a pattern onto a surface by using light. In the manufacture of semiconductors, it is the process that predefines the device features on the silicon wafer prior to the etch process steps.

Load error → The internal resistance of a voltmeter influences the measurements, this is called ~.

Load line → The ~ represents the relationship between current and voltage in the linear part of the circuit.

Local aligment → Finds sections of the sequences (conserved regions) with significant similarity

Local connection → In the neural network only a few neuron in a local area are connected to each other

Local field potential (LFP) → Electrophysiological signal which is dominated by the electrical current flowing from all nearby dendritic synaptic activity within a volume of tissue. A voltage is produced by the summed synaptic current flowing across the resistance of the local extracellular space.

Local rules → Local, pixel-level rule of a given task

Local/Global Descriptors → Descriptors that refer to a part of the structure are called local (a protein domain). Descriptors that refer to the entire structure (say protease) is a global descriptor.

Lock and key hypothesis → A model for substrate binding where the binding is based on the complementarity of the shape of substrate binding surface of the enzyme and the shape of the substrate.

Locked-in syndrome (LIS) → ~ is a condition in which a patient is aware and awake but cannot move or communicate verbally due to complete paralysis of all voluntary muscles in the body.

Locus coeruleus → A nucleus in the brainstem, which contains neurons producing norepinephrine and participate in stress-regulation.

Logarithmic quantization → The logarithmic implies here the range of the input values that map to each output value has a logaritmic relationship with the output value.

Logical product (VLSI design) → The common part of two sets (A és B), their logical product, intersection or conjunction are the elements that are simultaneously the elements of A and B. In mathematical logic it would be a conjuction.

Logical sum (VLSI design) → The elements that belong to set A or set B or both of them constitute the logical sum, or union of the two sets. In mathematical logic it would be a disjunction,

Long Term Evolution (LTE) → It is a 4G wireless broadband technology developed by the Third Generation Partnership Project (3GPP), an industry trade group.

Long-term depression (LTD) → ~ is a weakening of a synapse after a short series of presynaptic action potentials or asynchronous presynaptic and postsynaptic activity.

Long-term memory → A high-capacity part of the memory system in humans and other animals that stores information for extended time periods (from hours up to decades) and depends on enduring changes in synaptic efficacy and cellular properties.

Long-term potentiation (LTP) → Long-lasting enhancement in signal transmission between two neurons that results from stimulating them synchronously.

Loops → Non periodic, mainly unstructured secondary structural elements with a wide range of length.

Lorentz → Hendrik Antoon Lorentz (1853–1928) was a Dutch physicist (shared Nobel Prize in 1902) He derived the transformation equations subsequently used by Albert Einstein to describe space and time.

Lorentz force → The ~ is the force on a point charge due to electromagnetic fields. A positively charged particle will be accelerated in the same linear orientation as the electric field, but will curve perpendicularly to both the instantaneous velocity vector and the magnetic field according to the right-hand rule. The ~ law has a close relationship with Faraday’s law of induction.

Lorenz → Ludvig Valentin Lorenz (1829–1891) was a Danish mathematician and physicist. The Lorenz condition is a Lorentz invariant condition.

Lorenz gauge/Lorenz condition → The ~ is used in calculations of time-dependent electromagnetic fields through retarded potentials. The gauge fixing (choosing a gauge) denotes a mathematical procedure for coping with redundant degrees of freedom in field variables.

Low energy physics → Nonrelativistic physics ~ relativistic effects are neglible.

Lowest possible energy levels → For filling an atom with electrons in the ground state, the lowest energy levels are filled first and consistent with the Pauli exclusion principle,

Low-frequency TMS (slow TMS) → Repetition rate below 1 Hz.

Low-frequency transcranial magnetic stimulation (TMS) → ~ is a slow TMS: repetition rate of it is below 1 Hz.

Low-k Dielectric → Low-k type dielectric, which is placed between metal layers. Low-k type forms smaller capacitors that decrease signal propagation, increase dynamic power consumption

Lowpass filter → It is a filter that passes low-frequency signals but attenuates signals with frequencies higher than the cutoff frequency.

Low-pass filter → A ~ is a filter that passes low-frequency signals but attenuates signals with frequencies higher than the cutoff frequency. Also called high-cut filter.

L^p function space → A space of functions, where every function is integrable in p norm.

Lp/cm → Unit of resolution measurement= line pair(s) / cm.

LPCVD (Low-pressure chemical vapor deposition) → Low pressure is used during the growth of semiconducting materials bychemical vapor deposition (see Chemical Vapor Deposition, CVD).

LUMO Lowest (energy) unoccupied molecular orbital → ~ of a given ground state molecule where electron cannot be found. The previous energy level orbital is filled. The HOMO - LUMO energy gap is descriptive of the excitability of the molecule.

Lux-Flood acid base theory → a theory where acids are defined as oxide ion acceptors and bases as oxide ion donors

Lyapunov technique → A technique, with convergence of nonlinear recursion can be proven

Lyase → an enzyme which catalyzes the cleavage of bonds between two carbon atoms or between a carbon and a nitrogen atom

Lyases → Enzymes catalyzing double bond formation and removal.

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Macroelectromyography → ~ is an electromyographic technique by which all muscle electric activity produced by a single motor unit is recorded. Its clinical importance is in the judgment of reinnervation.

Macromolecule → A ~ is a very large molecule commonly created by some form of polymerization (molecules composed of many similar smaller molecules linked together).

Macrophage → a blood monocyte that migrates into tissues and ingests particulate material (e.g. oxidized LDL through scavenger receptors)

Macroshock → Any electrical current that passes through the skin and into the body that is larger than 10mA is considered a ~.

Macrostate → In describing a system made up of a great many particles, it is usually possible to specify some macroscopically measurable independent parameters, such as its temperature and pressure, which affect the particles’ equations of motion. It is characterized by a probability distribution of possible states across a certain statistical ensemble of all microstates. This distribution describes the probability of finding the system in a certain microstate.

Magnetic field → A ~ is a field of force produced by moving electric charges, by electric fields that vary in time, and by the ‘intrinsic’ ~ of elementary particles associated with the spin of the particle. There are two separate but closely related fields to which the name ‘magnetic field’ can refer: a magnetic B field (T, tesla, Vs/m²) and a magnetic H field (A/m). The ~ at any given point is specified by both a direction and a magnitude (or strength); as such it is a vector field. The ~ is most commonly defined in terms of the Lorentz force it exerts on moving electric charges.

Magnetic moment → The ~ of a magnet is a quantity that determines the force the magnet can exert on electric currents and the torque that a magnetic field will exert on it. A loop of electric current, a bar magnet, an electron, a molecule, and a planet all have magnetic moments. Both the ~ and magnetic field may be considered to be vectors having a magnitude and direction.

Magnetic resonance imaging (MRI) → A medical imaging technique used in radiology to visualize detailed internal structures. MRI makes use of the property of nuclear magnetic resonance (NMR) to image nuclei of atoms inside the body.

Magnetic susceptebility → The degree of magnetization of a material in response to an applied magnetic field.

Magnetism → ~ is a property of materials that respond at an atomic or subatomic level to an applied magnetic field. All materials are influenced to a greater or lesser degree by the presence of a magnetic field.

Magnetization → ~ is a measure of how a material responds when a magnetic field is applied to it. Magnetization also describes the way that a material changes the magnetic field, and can be used to calculate the forces that result from those interactions. Physicists define magnetization as the quantity of magnetic moment (vector) per unit volume. The origin of the magnetic moments can be either microscopic electric currents resulting from the motion of electrons in atoms, or the spin of the electrons or the nuclei.

Magnetocardiogram (MCG) → Graphical information about the magnetic activity of the heart.

Magnetoencephalography → MEG is an imaging process measuring and registering the magnetic field caused by the electric activity of the brain, with the help of sensitive detectors like SQUIDs (superconducting quantum interference).

Magnetoencephalography (MEG) → MEG is a non-invasive neurophysiological imaging technique that measures the magnetic fields generated by neuronal activity of the brain.

Mahalabonis distance → It is based on correlations between variables by which different patterns can be identified and analyzed. It gauges similarity of an unknown sample set to a known one.

MALDI (Matrix-assisted laser desorption/ionization) → A technique for generating macromolecular ions for MS without degradation .

Malignant → It means, that a disease has the tendency to become progressively worse.

Malleus → The ~ is hammer-shaped small bone in the middle ear. It is adjacent to the eardrum (tympanic membrane) and the incus and transfers sound waves from the former to the latter.

Manifold → Locally Euclidean topological space.

Many-body problem → The ~ deals with the properties of microscopic systems made of a large number of interacting particles. Microscopic here implies that quantum mechanics has to be used to provide an accurate description of the homogeneous or periodic system. The repeated interactions between particles create quantum correlations, or entanglement. The wave function of this system holds a large amount of information, so exact and/or analytical calculations are impractical, we have to rely on a set of approximations specific to the problem at hand, and ranks among the most computationally intensive fields of science.

Marker → Better oscilloscopes sometimes have movable bright markers on the trace that permit internal circuits to make more refined measurements