(a.) Extinguished; put out; quenched; as, a fire, a light, or a lamp, is extinct; an extinct volcano.
(a.) Without a survivor; without force; dead; as, a family becomes extinct; an extinct feud or law.
(v. t.) To cause to be extinct.
Example Sentences:
(1) The stages of mourning involve cognitive learning of the reality of the loss; behaviours associated with mourning, such as searching, embody unlearning by extinction; finally, physiological concomitants of grief may influence unlearning by direct effects on neurotransmitters or neurohormones, such as cortisol, ACTH, or norepinephrine.
(2) The effect upon ethanol responding was found not to resemble a pattern of extinction, but rather was best described as a general overall reduction in responding.
(3) In a recent study, Orr and Lanzetta (1984) showed that the excitatory properties of fear facial expressions previously described (Lanzetta & Orr, 1981; Orr & Lanzetta, 1980) do not depend on associative mechanisms; even in the absence of reinforcement, fear faces intensify the emotional reaction to a previously conditioned stimulus and disrupt extinction of an acquired fear response.
(4) We conclude that the procedure used in this study is a non-intrusive intervention that is an extension of the current literature pertaining to sensory extinction.
(5) After 40 programmed minutes of acquisition and 12 min of maintenance, without notice, both schedules changed to extinction for 28 min.
(6) This differential absorbance is linear with increasing concentrations of Na2MoO4 and was used to calculate the molar extinction coefficient of molybdochelin at 425 nm (epsilon similar to 6,200).
(7) However, during massed testing, all subjects trained with response contingent CS termination showed an overall extinction influence, which was most pronounced in the medial subgroup, although the laterals showed frequency control as well.
(8) When reinforcement for competing behavior was withdrawn, however, rats resumed their original behavior and there were no overall savings in total responses to extinction.
(9) The relative amount of the crystals was measured in both amoeba strains on the basis of the integral extinction value.
(10) Chronic extinction of chain closed conditioned reflex in intact rabbits took five to six days.
(11) The amounts of phosphatidylcholine and sphingomyelin could be determined by high-performance liquid chromatography and ultraviolet absorption if the apparent extinction coefficient of the material analyzed was established.
(12) In a number of neurones the extinction of reflexes either does not change the reaction to acetylcholine, or enhances it.
(13) In Experiment 3, following an unsignaled reinforcement delay, groups receiving either no event or signaled food in the context responded faster in extinction than groups receiving no context exposure or unsignaled food.
(14) The optical extinction decreases as the red cell agglutinates grow, giving a parametric estimate of the haemagglutination rate.
(15) By calculating for DNA standard solutions the value of the ratio between the extinction at 665 nm after 15 min to the extinction of 600 nm after 2 min of the orcinol reaction it is possible to increase specifiaty of the orcinol method for determination of the RNA content.
(16) To lose the Sundarbans would be to move a step closer to the extinction of these majestic animals," said ZSL tiger expert Sarah Christie.
(17) Values obtained for thebuoyant density, isoelectric point, and extinction coefficient differed minimally; major differences were observed in the molecular weight and the characterisitc width of cylinders formed by in vitro-assembled T-layer of the wild-type and variant.
(18) The CS+ preference persisted for several weeks during extinction tests when both the CS+ and CS- were paired with IG water or with no infusions.
(19) The extinction coefficient at 550 nm for the oxidized enzyme is about 5300 (M subunit)-1 X cm-1.
(20) On this planet, extinction is the norm – of the 4 billion species ever thought to have evolved, 99% have become extinct.
Nonexistent
Definition:
(a.) Not having existence.
Example Sentences:
(1) KCl thus appears to induce an intermediate which is either nonexistent when omitted or in such low concentration as not to be readily detected.
(2) The correlations of C3, C4, CH50 and factor B with abnormal clearance and disease activity were weaker or nonexistent.
(3) Anterior segment involvement was slight or nonexistent, and damage to the retina and uvea was of a focal rather than of a diffuse nature.
(4) Although the use of anticancer agents can be associated with severe side effects, on a practical basis complications of therapy are minimal to nonexistent.
(5) Early or late mortality among patients with isolated aortic coarctation was nonexistent, and it was 28.5% in patients with other congenital heart defects.
(6) Compartmentalization of germ cells in the seminiferous epithelium, therefore, was nonexistent.
(7) Doxycycline and other antibiotics have been implicated in oral contraceptive (OC) failure, but information is sparse and studies of a doxycycline-OC interaction are nonexistent.
(8) This enzymatic activity probably contributes to the steady state level of micronuclear histone acetylation that is low or nonexistent.
(9) But most of them were the first members of their family to adopt the veil, the majority had no niqab-wearing peers, their attendance at their mosque was minimal, and their affiliation to any Islamic bodies almost nonexistent.
(10) In the case of Wistar and Sprague-Dawley rats, the boosting effect of IL-2 on NK levels was either poor or nonexistent.
(11) Previous functional studies with the rat jugular vein have shown alpha-adrenergically mediated contraction was minimal to nonexistent, yet this tissue relaxed in response to norepinephrine via beta 1 and to isoproterenol via beta 2-receptor activation.
(12) After the third attempt, successful capsulotomies are either very rare or nonexistent.
(13) A small dependence of the intracellular relaxation rate on extracellular paramagnetic agent concentration, assumed nonexistent with the HG method, is inferred from the new analysis.
(14) The court relied on testimony of medical experts that the risk to patients from general practitioners with AIDS could be reduced, by training and education, to nonexistence, and emphasized that confidentiality is of paramount importance to AIDS patients and therefore is in the public interest.
(15) The thermodynamic study suggests a quantitative relationship of radiopharmaceutical:protein = 1:1 and an almost nonexistent influence of the temperature, which means that the interacting forces in this process are relatively weak.
(16) Hence in both groups, the percentage PRL suppression was significantly reduced compared with the control group, and indeed nonexistent in cortisol-nonsuppressed patients.
(17) In most instances, the evaluation is incomplete or nonexistent.
(18) In contrast, the infiltration of B lymphocytes was virtually nonexistent with few or no sIgM positive cells present in the lesions after either 4 or 14 days of exposure to ozone.
(19) "So it's nonexistent and it's false that we are at the moment looking for a goalkeeper."
(20) Although human studies are nonexistent, in those experimental organisms tested, using accepted techniques, LSD proved to be, at best, a weak mutagen, if mutagenic at all.