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991.
Keilin W. Gregory; Baker Jeff; McCutcheon Stephen; Peranson Elliott 《Canadian Metallurgical Quarterly》2007,1(4):229
This article provides a comprehensive analysis of the growing imbalance between the supply of predoctoral internship positions in psychology and the demand for such positions by graduate students. Data from the 2007 Match sponsored by the Association of Psychology Postdoctoral and Internship Centers (APPIC) are provided along with the results from several surveys of applicants from that year. An overview of applicant and program participation for the nine APPIC Matches that occurred between 1999 and 2007 is also provided. Implications of the increasing supply-demand imbalance for applicants, graduate and internship programs, and the profession are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Willem-Pier Vellinga Alexander Fedorov Jeff T. De Hosson 《Scientific Modeling and Simulation》2007,14(1):37-45
Mechanisms of the propagation of crack fronts along interfaces between a glassy polymer and metal or glass are discussed. Specifically, the systems studied are Poly-Ethylene Terephthalate (PETG) spin-coated on Al, PETG-glass and PETG hot-pressed on Cr-sputtered glass. Cracks studied propagate in an Assymetric Double Cantilever Beam (ADCB) geometry. Dependence of microscopic crack front geometry on propagation speed is found. The local stress state is found to have an impact on macroscopic as well as microscopic crack front geometry. Simple lattice model calculations of propagating crack fronts illustrate the impact of disorder and residual stress state on propagation mechanisms and macroscopic crack front shape respectively. 相似文献
993.
994.
VJ Massari LW Dickerson AL Gray JM Lauenstein KJ Blinder JT Newsome DJ Rodak TJ Fleming PJ Gatti RA Gillis 《Canadian Metallurgical Quarterly》1998,802(1-2):205-220
Recent physiological evidence indicates that vagal postganglionic control of left ventricular contractility is mediated by neurons found in a ventricular epicardial fat pad ganglion. In the dog this region has been referred to as the cranial medial ventricular (CMV) ganglion [J.L. Ardell, Structure and function of mammalian intrinsic cardiac neurons, in: J.A. Armour, J.L. Ardell (Eds.). Neurocardiology, Oxford Univ. Press, New York, 1994, pp. 95-114; B.X. Yuan, J.L. Ardell, D.A. Hopkins, A.M. Losier, J.A. Armour, Gross and microscopic anatomy of the canine intrinsic cardiac nervous system, Anat. Rec., 239 (1994) 75-87]. Since activation of the vagal neuronal input to the CMV ganglion reduces left ventricular contractility without influencing cardiac rate or AV conduction, this ganglion contains a functionally selective pool of negative inotropic parasympathetic postganglionic neurons. In the present report we have defined the light microscopic distribution of preganglionic negative inotropic neurons in the CNS which are retrogradely labeled from the CMV ganglion. Some tissues were also processed for the simultaneous immunocytochemical visualization of tyrosine hydroxylase (TH: a marker for catecholaminergic neurons) and examined with both light microscopic and electron microscopic methods. Histochemically visualized neurons were observed in a long slender column in the ventrolateral nucleus ambiguus (NA-VL). The greatest number of retrogradely labeled neurons were observed just rostral to the level of the area postrema. TH perikarya and dendrites were commonly observed interspersed with vagal motoneurons in the NA-VL. TH nerve terminals formed axo-dendritic synapses upon negative inotropic vagal motoneurons, however the origin of these terminals remains to be determined. We conclude that synaptic interactions exist which would permit the parasympathetic preganglionic vagal control of left ventricular contractility to be modulated monosynaptically by catecholaminergic afferents to the NA-VL. 相似文献
995.
Tight junctions between cells and adhesion to the substratum maintain the barrier function of epithelia throughout the body. Damage to the epithelial barrier by microbial products allows penetration of bacteria and promotion of infection. We studied the effects of Pseudomonas elastase (PE) on the barrier function of epithelia by using Madin-Darby canine kidney (MDCK) epithelial cells; these cells form tight junctions (zonula occludens [ZO]) in vitro. PE decreased electrical resistance across the monolayers in a concentration- and time-dependent manner. Immunostaining of selected proteins of the ZO and zonula adherens was used to explore the effects of PE on junctional proteins. PE-treated monolayers of MDCK cells had markedly decreased immunostaining of ZO-1, a protein of the ZO, but light microscopy of PE-treated cells revealed no obvious morphologic changes. A chromium release assay indicated that, even with marked changes in transmonolayer electrical resistance, the permeability defect was not due to membrane disruption. Fluorescence staining of F-actin indicated diminution of cellular microfilaments in PE-treated cells, but E cadherin (uvomorulin), a protein of the zonula adherens, was unaffected by the enzyme. Elastases from porcine pancreas and human leukocytes with similar enzymatic activity (6 U/ml) did not decrease transmonolayer electrical resistance or degrade ZO-1. These results suggest that PE disturbs the barrier function of epithelial monolayers, in part, by changing the cell architecture and altering at least one protein of the ZO. 相似文献
996.
Superficial dorsal penile vein thrombosis was diagnosed 8 times in 7 patients between 19 and 40 years old (mean age 27 years). All patients related the onset of the thrombosis to vigorous sexual intercourse. No other etiological medications, drugs or constricting devices were implicated. Three patients were treated acutely with anti-inflammatory medications, while 4 were managed expectantly. The mean interval to resolution of symptoms was 7 weeks. Followup ranged from 3 to 30 months (mean 11) at which time all patients noticed normal erectile function. Only 1 patient had recurrent thrombosis 3 months after the initial episode, again related to intercourse. We conclude that this is a benign self-limited condition. Anti-inflammatory agents are useful for acute discomfort but they do not affect the rate of resolution. 相似文献
997.
A procedure designed to test the transferability of habitat suitability criteria was evaluated in the Cache la Poudre River, Colorado. Habitat suitability criteria were developed for active adult and juvenile rainbow trout in the South Platte River, Colorado. These criteria were tested by comparing microhabitat use predicted from the criteria with observed microhabitat use by adult rainbow trout in the Cache la Poudre River. A one-sided X2 test, using counts of occupied and unoccupied cells in each suitability classification, was used to test for non-random selection for optimum habitat use over usable habitat and for suitable over unsuitable habitat. Criteria for adult rainbow trout were judged to be transferable to the Cache la Poudre River, but juvenile criteria (applied to adults) were not transferable. Random subsampling of occupied and unoccupied cells was conducted to determine the effect of sample size on the reliability of the test procedure. The incidence of type I and type II errors increased rapidly as the sample size was reduced below 55 occupied and 200 unoccupied cells. Recommended modifications to the procedure included the adoption of a systematic or randomized sampling design and direct measurement of microhabitat variables. With these modifications, the procedure is economical, simple and reliable. Use of the procedure as a quality assurance device in routine applications of the instream flow incremental methodology was encouraged. 相似文献
998.
P. D. Barnes Jr. A. Da Silva É. Aubourg D. S. Akerib D. Bauer D. Borden B. Cabrera D. O. Caldwell B. Chugg A. Cummings B. L. Dougherty J. Emes M. Gray D. Hale E. E. Haller K. D. Irwin A. E. Lange A. Lu S. Margulies M. J. Penn A. A. Pomansky B. V. Pritychenko R. R. Ross B. Sadoulet T. Shutt A. Smith G. Smith W. Stockwell J. Taylor S. White M. Witherell R. C. Wolgast S. Yellin B. A. Young 《Journal of Low Temperature Physics》1993,93(3-4):791-796
An experimental search for dark matter particle candidates using cryogenic detectors requires a low radioactive background environment. We discuss the status of a cryogenic dark matter experiment to be performed in the Stanford Underground Facility. The detectors will be cooled in a specially designed cryostat connected to a modified side access Oxford 400 dilution refrigerator. Details of the cryostat design and its operating performance are presented. The effectiveness of the multi-level shield surrounding the cryostat, as well as the background levels we expect to achieve in the pilot experiment are discussed. Finally, we examine the limits which can be set on dark matter candidates with such an experiment.Deceased 相似文献
999.
1000.