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21.
Abstract

The computer prediction of turbogenerator behaviour following fault or disturbance conditions has become an important feature in the assessment of machine system design, pre‐commissioning test appraisals, system operational procedures, machine monitoring strategy and post‐event damage diagnoses. In this paper computer methods are described to assess the comparative severity of various electrical faults and disturbances, the effect of specific operational practices together with the prediction of peak torsional transient behaviour. This paper is supported by realistic examples simulating the transient behaviour of a number of generational units.  相似文献   
22.
古今中外,无论是李白的“斗酒诗百篇“,还是拿破仑与挚爱干邑的生死与共,名人与酒总能结合在一起并演绎出一段载入史册的传奇故事,本期杂志专题将圈选一些品牌的名人故事,并将这些产品的历史文化进行详细的品读,解析这些名人和这些酒款相同的密码。  相似文献   
23.
This study examined whether reactance would negatively influence treatment outcome in 347 patients diagnosed with chronic forms of depression and treated at 9 sites with either Nefazodone, cognitive-behavioral analysis system of psychotherapy (CBASP), or combination therapy. Contrary to our hypotheses, reactance positively predicted treatment outcome in CBASP on 2 of 4 scales. These effects were independent of the therapeutic alliance, which also positively predicted outcome. Reactance did not predict outcome in the groups receiving medication alone or in combination with CBASP. The findings suggest that reactance may be an asset in psychotherapy among chronically depressed individuals and that reactant patients can benefit from directive psychotherapy when therapists flexibly respond to perturbations in the therapeutic relationship. Results support the importance of Aptitude × Treatment interactions in psychotherapy outcome. The direction and significance of such interactions may vary with different forms of psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
25.
BACKGROUND: This study has two goals: 1) to establish a generalizable model of the symptoms observed in outpatients with major depressive disorder (MDD); and 2) to compare symptom coverage of the Inventory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self-Report (IDS-SR) to that of the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI). METHODS: A factor analysis of IDS-C, IDS-SR, HDRS, and BDI items was carried out on 324 adult outpatients with MDD. Patients with coexisting Axis I or III illness or those taking psychotropic medication were excluded. RESULTS: Ten primary factors were identified, six of which were substantially intercorrelated, defining a second-order factor of general depression severity. Schmid-Leiman orthogonalization identified the symptoms most associated with general severity. CONCLUSIONS: The IDS provided more complete factors coverage than did the HDRS or BDI and thus may be more useful in research on symptom profiles.  相似文献   
26.
Girth measurements provide a simple method for estimation of total body fat that can be used over a wide range of percentage body fat (%BF). Well-established equations for determining %BF from girth measurements were applied to 42 Caucasian and 40 Polynesian women. %BF was determined from total body water measurement using oxygen-18 dilution. The relationship between the criterion measurement of %BF and that calculated from girth measurements differed significantly between the two ethnic groups. Assessment of body fat using girth measurements should use ethnicity-specific equations.  相似文献   
27.
The acute behavioral effects of buspirone (15 and 30 mg/70 kg), alprazolam (0.75 and 1.5 mg/70 kg), and placebo, alone and in combination with ethanol (0-0.6 mg/kg), were tested in 13 volunteers. Ethanol alone produced only a few significant behavioral effects. Alprazolam and buspirone produced comparable dose-related increases in participant ratings of sedation, but only alprazolam impaired performance. The buspirone-ethanol and alprazolam-ethanol combinations produced robust sedative-like participant-rated drug effects that were similar in magnitude, but, in general, only the alprazolam ethanol combinations impaired performance. These findings suggest that the participant-rated effects of therapeutic doses of buspirone in combination with moderate doses of ethanol are similar to those of therapeutic doses of alprazolam in combination with ethanol, but the performance-impairing effects of buspirone are distinguishable from those of alprazolam, alone and in combination with ethanol. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
OBJECTIVE: To investigate whether resting metabolic rate (RMR) differs between Caucasian and Polynesian women. DESIGN: Cross-sectional comparison. SUBJECTS: Eighty-two (42 Caucasian, 40 Polynesian) healthy women aged between 18 and 27 y. MEASUREMENTS: RMR (indirect calorimetry) and body composition (fat-free mass and fat mass derived from oxygen-18 dilution measurement of total body water). RESULTS: RMR was similar in the Caucasian (6956 +/- 1291 (s.d.) kJ/d) and Polynesian (7125 +/- 1290 kJ/d) groups while fat-free mass was significantly lower in the Caucasian group (45.3 +/- 6.8 vs 51.0 +/- 6.4 kg, P < 0.002). After adjustment for fat-free mass and fat mass, RMR was lower in the Polynesian than the Caucasian groups (6783 +/- 904 vs 7281 +/- 901 kJ/d, P = 0.023). CONCLUSION: The significantly lower relative RMR observed in Polynesian compared to Caucasian women may predispose Polynesian women to eventual onset of obesity.  相似文献   
29.
A kinetic study was carried out on the inhibitory effects of acarbose, maltose, and maltotriose on porcine pancreatic alpha-amylase (PPA), using maltopentaose as the substrate. Lineweaver-Burk plots showed that the inhibitory action of acarbose is of the mixed non-competitive type. The secondary plots gave straight lines. A model involving abortive complexes accounts for these results. Dixon plot analysis led to the same conclusion. According to the proposed model, one molecule of acarbose per amylase molecule binds either directly to free enzyme at the active site or to the enzyme-substrate complex at a secondary carbohydrate-binding site, which becomes functional after the substrate has bound to the enzyme molecule at the active site. Kinetic analysis of the inhibition exerted by either the maltose or maltotriose reaction products of maltopentaose hydrolysis were then performed. The inhibitory effect of maltose was found to be of the non-competitive type, while that of maltotriose was competitive. It can therefore be concluded that the first reaction product to be released upon maltopentaose hydrolysis is maltose, and that the second product is maltotriose. This indicates that after hydrolysis of the maltopentaose chain, the reducing side fragment is released first.  相似文献   
30.
OBJECTIVE: To determine alteration in adrenocortical function in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. ANIMALS: 6 horses with inducible and reversible heaves. PROCEDURE: Episodes of heaves were induced by exposure to moldy hay and straw for 7 days (natural challenge). Horses then underwent treatment (aerosolized beclomethasone, parenterally administered dexamethasone, and aerosolized propellant) for 7 days. Horses remained in the mold-contaminated environment for 7 days after discontinuation of drugs. Adrenocortical function was determine by serial evaluation of cortisol concentration in serum obtained on days 0, 7, 9, 12, 14, 16, 19, and 21. Adrenocorticotropic hormone stimulation testing was performed in 4 horses/treatment group on days 0, 7, 14, and 21. RESULTS: Endogenous cortisol production was suppressed in beclomethasone- and dexamethasone-treated horses within 2 days of treatment but recovered to values similar to those in propellant-treated horses approximately 2 and 4 days after discontinuation of drugs. Serum cortisol concentration in propellant-treated horses gradually decreased during the study and was significantly lower than baseline on days 14, 16, 19, and 21. Mean increase in serum cortisol concentration in response to ACTH stimulation testing after beclomethasone and dexamethasone administration did not differ significantly from the response observed in propellant-treated horses. CONCLUSIONS: Aerosol and parenteral administration of beclomethasone and dexamethasone, respectively, suppressed adrenocortical function; however, endogenous cortisol production resumed approximately 2 and 4 days after discontinuation of drugs. Responsiveness to ACTH stimulation testing was not affected by the 7-day treatment period.  相似文献   
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