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81.
This paper analyzes a method for identifying end-to-end connections in computer networks which is designed to provide reductions in the sizes of the packet headers and routing tables stored in the nodes. The method, known as Local Path ID Swapping, uses a shortened connection identifier, called the LPID, in the message headers and routing tables. In general, the LPID field is swapped in the message header from node to node along the path of the route. Some analytical results are presented for evaluating the important tradeoffs involved in LPID swapping. Most notable is the tradeoff between the size of the LPID field and the number of connections which can be defined in the network. 相似文献
82.
SF Abraham JR Blair-West JP Coghlan DA Denton DR Mouw BA Scoggins 《Canadian Metallurgical Quarterly》1976,81(1):120-132
Conscious sheep with permanent indwelling cannulae in the lateral ventricles and the cisterna magna were Na depleted and then perfused for 9 h with an artificial CSF solution. There were 3 experimental groups: Group I (n=5) received perfusion with aritifical CSF containing NA 170 MEq./1, Group II (n=7) received perfusion with artificial CSF containing Na 145 mEq./1, Group III (n=7) received no perfusion. In Group I the blood aldosterone level fell from 26.4 +/- 7.4 to 8.6 +/- 2.3 ng/100 ml by 9 h after perfusion. There was no significant change in plasma [Na] or [K], blood angiotensin II or plasma renin concentration. Blood cortisol and corticosterone levels rose. There was also a fall in post-perfusion. Group III showed no significant change in blood aldosterone concentration. Multivariate statistical analysis showed that the fall in aldosterone levels during 170 mEq./l Na perfusion could not be accounted for by changes, either alone or together, of ACTH as evidenced by alteration in blood cortisol or corticosterone, or by change of plasma [Na], [K] or renin concentrations. This data supports the hypothesis of an additional factor which may be of CNS origin being involved in the control of aldosterone secretion. 相似文献
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V. D. Shimanovich A. L. Mossé V. V. Azharonok E. M. Ermolaeva A. N. Knak 《Journal of Engineering Physics and Thermophysics》2001,74(4):962-969
The possibility of using a multijet electric arc plasmachemical reactor for decontamination and destruction of different powder pesticides with an expired effective date and storage life which have not been used in agriculture is studied. Studies of heat transfer are conducted on a setup operating without processing of raw material and with supply of pesticides (isophen and butyl ester of 2,4dichlorophenoxyacetic acid) to the reactor. The composition of waste gases at the reactor outlet is studied. 相似文献
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The pursuit of empirically supported therapies has resulted in controversy and further division between practicing and academic clinicians. The current article provides an overview of a clinical biopsychological model that may serve to guide assessment and treatment of many psychological problems, with a selective review of the literature supporting the model. One particular area, negative emotional memories, is discussed in theoretical and practical terms as related to the development of clients' psychological problems and how certain therapists' behaviors can positively and negatively affect clients. Next, the theorized effects of psychological treatments on negative memories are discussed. The article concludes with a call for efforts to pursue a neuropsychological model of treatment based on hypothesized causal factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
A G protein gamma subunit-like domain shared between RGS11 and other RGS proteins specifies binding to Gbeta5 subunits 总被引:1,自引:0,他引:1
BE Snow AM Krumins GM Brothers SF Lee MA Wall S Chung J Mangion S Arya AG Gilman DP Siderovski 《Canadian Metallurgical Quarterly》1998,95(22):13307-13312
Regulators of G protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) toward the alpha subunits of heterotrimeric, signal-transducing G proteins. RGS11 contains a G protein gamma subunit-like (GGL) domain between its Dishevelled/Egl-10/Pleckstrin and RGS domains. GGL domains are also found in RGS6, RGS7, RGS9, and the Caenorhabditis elegans protein EGL-10. Coexpression of RGS11 with different Gbeta subunits reveals specific interaction between RGS11 and Gbeta5. The expression of mRNA for RGS11 and Gbeta5 in human tissues overlaps. The Gbeta5/RGS11 heterodimer acts as a GAP on Galphao, apparently selectively. RGS proteins that contain GGL domains appear to act as GAPs for Galpha proteins and form complexes with specific Gbeta subunits, adding to the combinatorial complexity of G protein-mediated signaling pathways. 相似文献
89.
The historical development of the application of ozone to potable water treatment within the United Kingdom is reviewed up to 1990. The impact of privatization of the water utilities on the use of ozone is discussed and the process applications currently being considered are described. The paper concludes with a survey of water treatment plants which are using ozone in 1993, and those planned for completion by the year 2000. 相似文献
90.
SF Malamed 《Canadian Metallurgical Quarterly》1993,124(8):40-53
A simple dental procedure can quickly escalate into a medical emergency. Management of six common emergencies is described. 相似文献