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1.
A General Role for Early Onset Cues and Intra-Event Learning; Comment on McDonald and Siegel (2004).
Research on classical conditioning with drug unconditional stimuli has had a profound effect on the understanding of general conditioning processes. The experiment reported by R. V. McDonald and S. Siegel (see record 2004-10475-001) demonstrates that cues coincident with the onset of an event can become associated with the rest of the event. This sort of learning is probably ubiquitous and has been proposed as a mechanism behind the development of panic disorder, in which interoceptive cues coincident with the start of a panic attack can be associated with the rest of the attack and can eventually come to elicit full-blown panic on their own. Evidence that extinction exposure to early onset cues can reduce their power is especially important. Drug conditioning research continues to provide a powerful testing ground for important general principles of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
通过分析钢水在结晶器内凝固的不均匀性及对钢水结晶的热量平衡计算,讨论连铸中间包钢水温度、结晶器冷却水流量及进出水温差对拉坯速度的影响。 相似文献
3.
Lawrence K. Forbes Graeme C. Hocking Simon Wotherspoon 《Journal of Engineering Mathematics》2004,48(1):69-91
Rainwater can collect in a lens-shaped region within the rock of a tropical island, and may be separated from the underlying salt water by a sharp interface. This paper presents a nonlinear theory for determining the shape of this interface. The island is assumed to be saturated with rain, and provision is made for the outflow of rain-water through the sides of the island. The effect of a bore well on the shape of the interface is investigated, and the problem is solved using a spectral method. An integral-equation method is also presented for the case when the island has infinite width. 相似文献
4.
Withdrawal from an escalating-dose, bingelike regimen of cocaine administration in rats produced significantly depressed levels of locomotor activity during the nocturnal portion of the day-night cycle. This effect was observed during the first 48 hrs of testing. Extracellular single-unit recordings of ventral tegmental area (VTA) dopamine (DA) neurons revealed no differences between saline- and cocaine-treated rats with respect to basal firing rates. However, significantly fewer spontaneously active VTA DA neurons were encountered in rats withdrawn from binge cocaine. As with the nocturnal hypoactivity, this effect was observed only during the first 48 hrs of withdrawal. These findings suggest that short-term DA neuron dysfunction during cocaine withdrawal temporally corresponds to behavioral disruptions that are similar to those described in human addicts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Previous research has shown that under certain conditions environmental cues associated with morphine administration induce drug-opposite conditioned effects that mimic symptoms of opiate withdrawal. R. V. McDonald and S. Siegel (see record 2004-10475-001) extend these observations by demonstrating that acute exposure to a low dose of morphine induces symptoms of opiate withdrawal in rats previously exposed to a high dose of morphine. They hypothesized that early drug onset cues, repeatedly paired with later, larger drug effects, mediate the paradoxical effect of the low drug dose on behavior. They also hypothesized that conditioned withdrawal symptoms induced by the early drug onset cues may mediate the "priming" effect of drugs on relapse and craving. The authors of this comment discuss the degree to which the literature supports this hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
R. V. McDonald and S. Siegel (see record 2004-10475-001) present new evidence for the idea that opioid drug-opposite responses can become conditioned to cues of initial drug onset and that they could, therefore, play a role in the development of tolerance of some drug effects and a role in the elicitation of withdrawal-like symptoms in cases in which addicted individuals are exposed to small doses of the drug they normally consume. In this comment, some puzzling features of the data are discussed, and alternative explanations are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
濮城油田开发后期,因事故导致损坏的井数不断增多,不仅损失了相当一部分储量,而且严重威胁着油田的发展。针对这一问题,应用拔套侧钻工艺技术对有潜能的事故井进行侧钻更新,投产后取得了良好的效果,成为油田增储上产和挖潜剩余油的重要手段,同时也为解决困扰油田发展的难题找到了好的方法。 相似文献
8.
Piasecki Thomas M.; Jorenby Douglas E.; Smith Stevens S.; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2003,11(4):276
Five parameters of postcessation smoking withdrawal variability derived from clinical data (T. M. Piasecki, D. E. Jorenby, S. S. Smith, M. C. Fiore, & T. B. Baker, 2003a, 2003b) were predicted from baseline measures and pharmacotherapy assignment. Smokers who were more dependent, older, and high in negative affect reported more severe withdrawal. Women, heavier smokers, and those with a history of depression reported more variable symptoms. Smokers treated with nicotine patch, bupropion, or both reported less severe withdrawal than did those given placebo, but medication did not affect the slope of symptoms over time, day-to-day variability of symptoms, or the size of acute changes in symptoms associated with lapses to smoking. Prior research has shown that these symptom facets predict later relapse: thus, current pharmacotherapies may aid cessation by diminishing withdrawal severity, but they do not affect all clinically important aspects of withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Wood dowels are commonly used in the construction furniture, but little information is available about the additive effects of dowels on the ultimate withdrawal strength of single or multidowel joints. This study was carried out to determine the tensile strength of 10‐mm‐diameter dowels produced from medium‐density fiberboard (MDF), plywood, scotch pine (Pinus sylvestris L.), and beech (Fagus orientalis lipsky), bonded parallel and vertical to the surface of MDF and particleboard (Pb) with poly(vinyl acetate) (PVAc) and Desmodur‐VTKA (D‐VTKA). Tensile strength was applied to the dowels according to the procedure in the ASTM‐D 1037 standard. The effects of dowel species, direction of tensile, composite material, and type of adhesive on tensile strength were determined. The results showed that the highest tensile strength was obtained in beech dowels bonded vertically with PVAc adhesive to the surface of MDF at 7.91 N/mm2. If the dowels used in furniture production are subjected to great tensile strength, beech dowels bonded with PVAc adhesive on MDF should be used. However, when dowels produced from MDF and plywood waste are used, they also can produce positive results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 531–535, 2003 相似文献
10.