(n.) The act of perturbing, or the state of being perturbed; esp., agitation of mind.
(n.) A disturbance in the regular elliptic or other motion of a heavenly body, produced by some force additional to that which causes its regular motion; as, the perturbations of the planets are caused by their attraction on each other.
Example Sentences:
(1) These membrane perturbation effects not observed with bleomycin-iron in the presence of a hydroxyl radical scavenger, dimethyl thiourea, or a chelating agent, desferrioxamine, were correlated with the ability of the complex to generate highly reactive oxygen species.
(2) Ultraviolet difference spectrophotometry indicates that the inactivated enzyme retains its capacity for binding the nucleotide substrates whereas the spectral perturbation characteristic of 3-phosphoglycerate binding is abolished in the modified enzyme.
(3) It is suggested that laboratory experiments should be performed on perturbed systems only if simulations have shown that the methods of data analysis will be satisfactorily powerful and accurate.
(4) Thresholds were measured for detecting perturbations in a regular lattice of dots by modulating local dot density, local dot luminance, or some combination of the two.
(5) It is shown that when a constant current is applied such that a stable equilibrium and rhythmic firing are present, the following predictions are inherent in the HH system of equations: (a) Small instantaneous voltage perturbations to the axon given at points along its firing spike result in phase resetting curves (when new phase versus old phase is plotted) with an average slope of 1.
(6) Lower lip perturbation duration was manipulated to yield two different load conditions.
(7) The role of the Golgi complex in the post-translational oligosaccharide maturation of alpha-amylase was explored by use of the carboxylic ionophore, monensin (10(-7)M), a known perturbant of the structure and function of the Golgi complex.
(8) The importance of the ionic interaction due to the formation of the salt bridge between the Asp-27 and the pteridine ring in Escherichia coli dihydrofolate reductase-methotrexate complex has been studied by using the free-energy perturbation method.
(9) Presence of the monosynaptic reflex during platform perturbations at normal latencies suggests that balance problems in children with Down syndrome do not result from hypotonia, which researchers have defined as decreased segmental motoneuron pool excitability and pathology of stretch reflex mechanisms, but rather result from defects within higher level postural mechanisms.
(10) We have perturbed the dynamics of the nuclear lamins by means of cell fusion between mitotic and interphase cells and have studied redistribution of lamins in fused cells as a function of extracellular pH levels.
(11) In the coagulating gland, this compensatory response involved the proliferation of many cells which, in the absence of cytotoxic perturbation, would be non-proliferatie (Q cells).
(12) The effect of initial perturbation of the thrombus by a guide wire appears to be less important than the thrombus disruption and accelerated thrombolysis caused by the pulsatile delivery system.
(13) As before, subjects were instructed to either oppose the perturbation (Predictable Oppose) or relax the forearm muscles (Predictable Let-Go).
(14) Bivalent cations (Ca2+, UO2(2+) or Zn2+) in the subphase at pH 5.6 significantly modified the behaviour of mixed monolayers of fusogenic lipids with phospholipids; there was a parallel perturbing effect of fusogenic lipids on interactions between monolayers of phospholipids and bivalent cations.
(15) In particular, nitration of Tyr-51 provoked a structural perturbation in the globular region.
(16) Altering the biophysical characteristics of cell membranes by diet and membrane perturbing agents markedly influences thermosensitivity of cells.
(17) Paraphilias (PAs) and non-paraphilic sexual addictions (NPSAs) may be behaviors that share a common perturbation of central serotonin neuroregulation as a component of their pathophysiology.
(18) Two functions of these have been proposed: 1) that they are compatible osmolytes which regulate cell volume (against high external NaCl) without inhibiting proteins and 2) that methylamines (GPC and betaine) are counteracting osmolytes which stabilize proteins against perturbation from high renal urea.
(19) This high incidence of HER2 gene amplification with accompanying overexpression in non-invasive breast tumors suggests that perturbations of the HER2 oncogene are among the earliest and most common genetic lesions in human breast cancer.
(20) Hypophysectomy was selected as a model system for perturbing testicular cell types, since the cytological sequelae of this treatment post-hypophysectomy in the rat are well documented in the literature.
Stability
Definition:
(a.) The state or quality of being stable, or firm; steadiness; firmness; strength to stand without being moved or overthrown; as, the stability of a structure; the stability of a throne or a constitution.
(a.) Steadiness or firmness of character, firmness of resolution or purpose; the quality opposite to fickleness, irresolution, or inconstancy; constancy; steadfastness; as, a man of little stability, or of unusual stability.
(a.) Fixedness; -- as opposed to fluidity.
Example Sentences:
(1) Simplicity, high capacity, low cost and label stability, combined with relatively high clinical sensitivity make the method suitable for cost effective screening of large numbers of samples.
(2) What's to become of Tibetan stability and cohesion then is anyone's guess.
(3) 5-Azacytidine (I) stability was increased approximately 10-fold over its stability in water or lactated Ringer injection by the addition of excess sodium bisulfite and the maintenance of pH approximately 2.5.
(4) However, ticks, which failed to finish their feeding and represent a disproportionately great part of the whole parasite's population, die together with them and the parasitic system quickly restores its stability.
(5) The direct monocyte source is not sufficient to insure the stability of this population.
(6) A cDNA library prepared from human placenta has been screened for sequences coding for factor XIIIa, the enzymatically active subunit of the factor XIII complex that stabilizes blood clots through crosslinking of fibrin molecules.
(7) The diastereoisomers appeared to differ in stability.
(8) Thermal stabilities (Tm's) of the hybrid between the 2'-O-methyl ribooligomer and the complementary ribooligomer and of the related hybrids are compared.
(9) The influence of calcium ions on the electrophoretic properties of phospholipid stabilized emulsions containing various quantities of the sodium salts of oleic acid (SO), phosphatidic acid (SPA), phosphatidylinositol (SPI), and phosphatidylserine (SPS) was examined.
(10) The method used in connection with the well known autoplastic reimplantation not only presents an alternative to the traditional apicoectomy but also provides additional stabilization of the tooth by lengthing the root with cocotostabile and biocompatible A1203 ceramic.
(11) Prompt diagnosis, in which timely diagnostic laparoscopy and ultrasound evaluation of the pelvis may be helpful, provides the opportunity for prompt laparotomy with untwisting of the torsion and stabilization of the adnexa by suture and cystectomy, if possible, extirpation if not.
(12) The cell fermentation culture with a stabilized pH value was better than the culture with the pH value changing spontaneously on saponin content, growth rate and biomass.
(13) It is proposed that microoscillations of the eye increase the threshold for detection of retinal target displacements, leading to less efficient lateral sway stabilization than expected, and that the threshold for detection of self motion in the A-P direction is lower than the threshold for object motion detection used in the calculations, leading to more efficient stabilization of A-P sway.
(14) Stability of kinetic constants for a long period of time is demonstrated.
(15) Poly (8NH2G) does not interact with poly(C) in neutral solution because of the high stability of the hemiprotonated G-G self-structure.
(16) The elongation of helix III with the addition of helix II at the N-terminus somewhat stabilizes the ordered structure.
(17) Replacement of vinyl groups with bulkier substituents (hydroxyethyl or acetyl groups) decreases holoenzyme stability and catalytic activity.
(18) The stabilized mandible allowed suspension of the tongue.
(19) In a family with hereditary elliptocytosis and an abnormality in spectrin self-association, the membranes had decreased deformability and stability.
(20) In testing the contribution of the long, curved stem to the torsional stability of uncemented prostheses by comparing it with other stems, the long, curved stem was the most stable, followed by a shorter straight stem, and a short, proximally curved stem.