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991.
Yuan-Yih Hsu Chuan-Sheng Liu Tain-Syh Luor Chung-Liang Chang Ah-Shing Liu Yung-Tien Chen Chiang-Tsung Huang 《Power Systems, IEEE Transactions on》1996,11(2):747-753
Experience with the identification and tuning of exciter constants for a generating unit at the second nuclear power plant of the Taiwan Power Company is reported. A field test is first performed on the excitation system with the generator open-circuited. Since the field test results differ from the computer simulation results using manufacturer's constants, the authors first modify the manufacturer's constants based on their previous experience to reach a preliminary set of parameters for the excitation system. Then a hybrid nonlinear simulation-sensitivity matrix method is developed to further refine the excitation system parameters. The exciter constants are tuned in order to give better dynamic response before a power system stabilizer is applied to the generator. Field tests are then performed in order to compare the dynamic response of the generator without and with power system stabilizer 相似文献
992.
From May 1991 to May 1994, Lyme borreliosis was studied prospectively in 301 residents living on Asp?, a highly endemic area for the disease. The study included annual questionnaires and blood samples for serology. Immunoglobulin G (IgG) antibodies to Borrelia burgdorferi sensu lato were detected by enzyme-linked immunosorbent assay in 63/301 (21%) of the residents at the start of the study. Seropositivity rates increased with time, and 3 years later 101/301 (34%) were positive. A total of 34 individuals developed physician-verified manifestations of Lyme borreliosis during the study period. Nine individuals developed an erythema migrans, despite a previously treated Lyme borreliosis or pre-existing high levels of IgG antibodies to B. burgdorferi s.l. 相似文献
993.
D Osoba NK Aaronson M Muller K Sneeuw MA Hsu WK Yung M Brada E Newlands 《Canadian Metallurgical Quarterly》1996,5(1):139-150
A self-report questionnaire module consisting of 24 items, comprising 5 scales and 7 single items, has been developed for measuring health-related quality of life in patients with brain cancer. Module development proceeded through several stages, including a listing of patient, family and health care professional concerns, the writing of items, field testing in 105 patients with brain cancer and subsequent item reduction and scale construction after multitrait scaling analysis and assessment of internal consistency (Cronbach's coefficient alpha). The final version of the module exhibits reasonable test-retest stability over a period of one week. Differences in the responses between patients with recently-diagnosed and recurrent cancer and between patients with a Karnofsky Performance Score (KPS) of 50-70 and 80-100 were in the expected direction, indicating that the module of questions is responsive to differing conditions. Patients with either mental confusion, motor deficit or dysphasia indicated problems in several domains and single items as compared to patients without these neurological deficits. Thus, differences in the responses to the items in the brain cancer module appear to reflect differences in neurological status. In addition, deteriorating neurological status was accompanied by a marked increase in emotional distress, future uncertainty and motor dysfunction. A comparison of the responses in the module with the KPS and with a modified Barthel Activities of Daily Living Index (BADLI) shows moderate correlations, primarily with scales and items that pertain to motor dysfunction, while other scales (such as emotional distress, visual disorder and communication deficit) and most single items are not associated with the KPS or BADLI. Since the emotional distress scale of the module was found to be highly correlated with the emotional function scale of the EORTC QLQ-C30, it could be omitted when the module is used in combination with the QLQ-C30. This would reduce the module to a total of 20 items with four scales and seven single items. The intention is to combine this module of questions with other core or general quality-of-life questionnaires when studying patients with brain cancer in clinical trials. 相似文献
994.
Recent research has found a discrepancy between schizophrenic patients' outward expression of emotion and their reported emotional experience. In this study, which attempts to replicate and extend the findings of previous studies, participants with and without schizophrenia viewed emotional film clips while their facial expressions were videotaped and skin conductance was recorded. Participants also reported their subjective experience of emotion following each film. Those with schizophrenia were less facially expressive than controls during the emotional films and reported experiencing as much positive and negative emotion, replicating previous findings. Additionally, schizophrenic patients exhibited greater skin conductance reactivity to all films than controls. These findings suggest a disjunction among emotional response domains for schizophrenic patients; alternative explanations for the findings are considered as well as suggestions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Yeong-Maw Hwang Hung-Hsiou Hsu Hung-Jen Lee 《International Journal of Mechanical Sciences》1995,37(3)
A mathematical model for symmetrical sandwich sheet rolling is proposed by using the stream function method and the upper bound theorem to investigate the plastic deformation behavior of sheets at the roll-gap. The velocity fields derived from the newly proposed stream functions can automatically satisfy the volume constancy and the velocity boundary conditions within the roll-gap. Effects of various rolling conditions such as the thickness ratio and flow stress ratio of sheets, total thickness reduction, friction factor between the sheet and roll, etc., upon the thickness ratio of the rolled product, the relative length of the plastic region in each layer, rolling force and rolling power are discussed systematically. Furthermore, experiments on sandwich sheet rolling are also conducted by employing aluminium, mild steel and stainless steel as layers of sandwich sheets. It is found that the theoretical predictions of the thickness ratio of the rolled products and rolling force are in good agreement with the experimental measurements. Through the study, it becomes clear that the proposed analytical method is applicable for simulating the sandwich sheet rolling processes and is able to offer useful knowledge in manufacturing sandwich sheets. 相似文献
996.
Jusczyk Peter W.; Jusczyk Ann Marie; Kennedy Lori J.; Schomberg Tracy; Koenig Nan 《Canadian Metallurgical Quarterly》1995,21(4):822
This study examined 2- to 3-month-olds' representations of bisyllables. In 3 experiments, infants were familiarized with sets of bisyllables that either did or did not share a common consonant–vowel (CV) syllable. In Experiment 1, infants detected the presence of a new bisyllable in the test phase except when it shared a common initial CV syllable. A modified version of the high-amplitude sucking procedure, incorporating a 2-min delay period, tested infants' retention of information about bisyllables in the remaining 2 experiments. In Experiment 2, infants were significantly more likely to retain information about bisyllables that shared the same initial CV syllable. Finally, the authors investigated whether infants simply benefited from the presence of 2 common phonetic segments, regardless of whether these came from the same CV syllable. The results showed that CV syllable organization is important in infants' ability to encode and retain information about bisyllables. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
998.
OBJECTIVE: Our purpose was to compare and correlate amniotic fluid GRO-alpha, interleukin-8, and L-selectin in patients with and without intraamniotic infection. STUDY DESIGN: Amniocentesis was performed on 45 pregnant women with preterm contractions, labor, or rupture of membranes. Fourteen patients had intraamniotic infection, and 31 did not. Intraamniotic infection was defined as the presence of a positive amniotic fluid culture. Amniotic fluid tests for Gram stain, glucose, neutrophil counts, creatinine, pH, and specific gravity were performed. Amniotic fluid levels of soluble L-selectin, interleukin-8, and GRO-alpha were measured by an enzyme-linked immunoassay and normalized by amniotic fluid creatinine levels. The Mann-Whitney Utest and Spearman's rank correlation test were used for statistical analyses. RESULTS: Amniotic fluid median levels of soluble L-selectin, interleukin-8, and GRO-alpha were significantly higher in pregnant women with intraamniotic infection than in those without intraamniotic infection (soluble L-selectin: median 3334.6 ng/mg creatinine, range 408.4 to 15,956.8 vs 717.2 ng/mg creatinine, range 129.4 to 4601.9, p = 0.009; GRO-alpha: median 841.6 ng/mg creatinine, range 28.1 to 8591.7 vs 56.8 ng/mg creatinine, range 0.0 to 440.2, p < 0.0001; interleukin-8: median 4932.7 ng/mg creatinine, range 0.0 to 55,058.7 vs 28.3 ng/mg creatinine, range 0.0 to 1161.6, p = 0.0004). Patients with intraamniotic infection had significantly higher amniotic fluid leukocyte counts and leukocyte esterase activities and significantly lower amniotic fluid glucose concentrations compared with those without intraamniotic infection. Amniotic fluid GRO-alpha, interleukin-8, and soluble L-selectin were positively correlated, and each was positively correlated with amniotic fluid leukocytes and negatively correlated with amniotic fluid levels of glucose. CONCLUSIONS: Our data indicate amniotic fluid GRO-alpha and interleukin-8 may be two potent leukocyte chemoattractants and activators, and L-selectin is rapidly shed from leukocytes in the amniotic fluid in patients with intraamniotic infection. 相似文献
999.
Lutgendorf Susan K.; Antoni Michael H.; Ironson Gail; Klimas Nancy; Kumar Mahendra; Starr Kathleen; McCabe Philip; Cleven Karen; Fletcher Mary Ann; Schneiderman Neil 《Canadian Metallurgical Quarterly》1997,65(1):31
This study tested the effects of a 10-week group cognitive–behavioral stress management (CBSM) intervention on mood and immunologic parameters in HIV-seropositive gay men whose disease had progressed to a symptomatic stage. Men were randomized to either CBSM or a modified waiting-list control group. The CBSM intervention significantly decreased self-reported dysphoria, anxiety, and total distress. Individuals who practiced relaxation more consistently had significantly greater drops in dysphoria. The intervention also decreased herpes simplex virus-Type 2 (HSV-2) immunoglobulin G antibody titers. The control group showed no significant changes in either mood or antibody titers. Individual difference analyses revealed that decreases in dysphoria significantly predicted lower HSV-2 antibody titers by the end of the 10-week period. Neither group displayed changes in HSV-Type I antibody titers or in CD4+ or CD8+ cell numbers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Leukocyte transfusion-associated granulocyte responses in a patient with X-linked hyper-IgM syndrome
TP Atkinson CA Smith YM Hsu E Garber L Su TH Howard JT Prchal MP Everson MD Cooper 《Canadian Metallurgical Quarterly》1998,18(6):430-439
X-linked hyper-IgM syndrome (XHIM) is a severe congenital immunodeficiency caused by mutations in CD154 (CD40 ligand, gp39), the T cell ligand for CD40 on B cells. Chronic or cyclic neutropenia is a frequent complicating feature that heightens susceptibility to severe infections. We describe a patient with a variant of XHIM who produced elevated levels of serum IgA as well as IgM and suffered from chronic severe neutropenia. Eight of ten leukocyte transfusions with cells from a maternal aunt, performed because of mucosal infections, resulted in similar episodes of endogenous granulocyte production. Transfection studies with the mutant CD154 protein indicate that the protein is expressed at the cell surface and forms an aberrant trimer that does not interact with CD40. The data suggest that allogeneic cells from the patient's aunt, probably activated T cells bearing functional CD154, may interact with CD40+ recipient cells to produce maturation of myeloid precursors in the bone marrow. 相似文献