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981.
Cheul Shim Intae Ryoo Junho Lee SangBae Lee 《Selected Areas in Communications, IEEE Journal on》1994,12(2):332-344
The authors propose a new method for the modeling and call admission control (CAC) of variable bit rate video source, which come to the front of ATM networks as hot issues nowadays. First, the modeling of video source is accomplished using the three-state Markov chains including the effects of scene change at which the bit rate of video source is abruptly increased. Also, using two AR models, they improve the defects which an AR model has in modeling a video source. In addition, they represent the analytical model of a video source so that a network manager can acquire the information which is very important in managing the entire networks. CAC is accomplished using the previously defined analytical model. A routing manager calculates the cell loss probability of a chosen VP where a new call is connected so that the routing manager decides whether this new call is accepted or not. This calculation is accomplished through the GB/D/1-S queuing system. Using BIA (bandwidth increasing algorithm), they check whether the calls rejected by the routing manager could be accepted if possible. Finally, the applicable procedures to suitable allocate bandwidth to each VP on a link are presented in detail 相似文献
982.
983.
OBJECTIVE: To assess the educational value of a practice-based ambulatory program used at a school of veterinary medicine. DESIGN: Retrospective cohort study. SAMPLE POPULATION: Graduates of US veterinary medical schools between 1987 and 1994. PROCEDURE: Phase I involved use of interviews and focus groups to assist in development of the questionnaire used in phase II, a retrospective cohort study. The pretested questionnaire was sent to a study population consisting of all graduates of the University of Wisconsin-Madison, School of Veterinary Medicine, between 1987 and 1994 as well as a control group who were randomly selected from the 1994 AVMA list of veterinarians. Control-group veterinarians were matched on the basis of professional activity, region, and year of graduation. RESULTS: 728 of 1,067 veterinarians completed the questionnaire in phase II of the study (response rate, 68%). The practice-based ambulatory program at the University of Wisconsin-Madison compared favorably with university-based ambulatory programs in volume of experiences and perceived educational quality. Regardless of rotation type, female students were significantly less likely to observe or perform 12 specific clinical procedures and were significantly less likely to rate instructional quality as excellent or very good, compared with male students. CLINICAL IMPLICATIONS: Practice-based ambulatory rotations can be a good alternative to existing university-based ambulatory rotations. Implementation of these programs should emphasize performance of procedures while striving to ensure participation of female students. 相似文献
984.
JW Larrick 《Canadian Metallurgical Quarterly》1997,276(5314):881-882
985.
A Shilatifard D Haque RC Conaway JW Conaway 《Canadian Metallurgical Quarterly》1997,272(35):22355-22363
986.
JW Williamson 《Canadian Metallurgical Quarterly》1997,32(1):22-31
Influx of the purine nucleoside, adenosine, was assessed in erythrocytes from both normal subjects and from subjects with a range of genetically determined erythrocyte disorders from Myanmar. The latter included alpha-thalassemia major (Myanmar variant), beta-thalassemia major (Myanmar variant), beta-thalassemia trait, HbEE and HbAE erythrocytes and two variants of glucose-6-phosphate dehydrogenase (G6PDH) deficiency. Significant reductions (p < 0.01) of adenosine influx were observed in erythrocytes from individuals with alpha- and beta-thalassemia major and severe G6PDH deficiency. Abnormal erythrocytes infected with the malarial parasites, Plasmodium falciparum or Plasmodium vivax, demonstrated a reduction in adenosine transport which correlated with the proportion of abnormal erythrocytes present in the samples obtained. The effect of nitrobenzylthioinosine (NBMPR) on adenosine influx was explored in normal and abnormal erythrocytes. In all these cases, NBMPR completely inhibited the transport of adenosine. However, transport of adenosine into P. falciparum and P. vivax-infected normal erythrocytes and abnormal cells was only inhibited 50-60% by NBMPR. The combination of tubercidin and NBMPR completely blocked adenosine transport into both normal and abnormal erythrocytes infected with either P. falciparum or P. vivax. 相似文献
987.
pRb controls cell proliferation by restricting inappropriate entry of cells into the cell division cycle. As dephosphorylation of pRb during mitotic exit activates its growth suppressive function, identification of the protein phosphatase that dephosphorylates pRb, and characterization of the mechanism of its regulation, are essential to elucidating the mechanisms of cell growth control. By fractionating mitotic CV-1P cell extracts, we identify the protein phosphatase which dephosphorylates pRb as a type 1 serine/threonine phosphoprotein phosphatase (PP1). Molecular sizing analyses indicate that the catalytic enzyme (PP1c) is present in a high molecular weight complex, with a predicted molecular mass of 166 kDa. PP1-interacting proteins in the mitotic cell extracts are identified. Two PP1-interacting proteins (41 and 110 kDa) are shown to form distinct complexes with PP1c from fractions of separated mitotic cell extracts containing phosphorylase phosphatase activity. However, only the 110-kDa PP1-interacting protein is present in fractions containing pRb-directed phosphatase activity, identifying this protein as a putative activator of PP1 function toward pRb during mitosis. 相似文献
988.
Patients with preterm labor not only suffer from anxiety and uncertainty regarding the healthy development of their child but, especially as inpatients, in part severely from loss of autonomy and feelings of insufficiency. By the creative therapeutic means of art therapy it is aimed at influencing the disturbed emotional state and strengthening self-esteem. During the sessions patients experience challenge, success and relaxation with endurance some time after the sessions. Paintings produced by hospitalized patients in art therapeutic sessions are presented. Further psychophysiological investigations are in process for controlling the effects on preterm labor. Paintings of inpatients are discussed. 相似文献
989.
990.