Natural convection transients and their effects in unidirectional solidification

A formulation is given and computed solutions are presented for transient solidification accompanied by natural convection in a vertical slot. It was found that appreciable fluid velocities may be produced by natural convection, the values of which could be comparable to the terminal rising velocities of typical nonmetallic inclusions. The simplifying assumptions made limit the validity of the solutions to systems where GrPr < 500,i.e., to narrow slots or to low values of the superheat; nonetheless, the results should be indicative of the effects of convection at much higher values of GrPr. Formerly Post-Doctoral Research Associate, State University of New York at Buffalo     

A Compact, Microprocessor-Based ECG ST-Segment Analyzer for the Operating Room

We describe a microprocessor-based device for analyzing ST-segment changes of the electrocardiogram in the operating room during general anesthesia. The device identifies significant components of the ECG waveform, detects arrhythmias, and performs ST-segment measurements. Measured values of heart rate, QRS duration, R-wave magnitude, and ST-segment level, slope, area, and index are selectively displayed on a front-panel numeric display and can be recorded in analog form with an FM tape recorder. Provided are details of the battery-operated hardware, the ST-analysis software, and the results of 60 h of clinical trials. Possible uses are proposed for trend analysis during anesthesia.     

Cost-effectiveness of providing insurance benefits for posthospital psychiatric halfway house stays.

A model insurance benefit package for posthospitalization psychiatric halfway house care was developed and administered to 32 hospitalized mentally ill persons. The therapeutic and cost effectiveness of providing a 120-day benefit package was examined over a 14-mo posthospitalization period. This was compared with the effectiveness of hospitalization benefits alone for the same patients over the 42 mo prior to halfway house admission. In terms of therapeutic efficacy, there was no significant deterioration after hospitalization release in either the symptom or behavioral coping scales, except for an increase in somatization. Yearly hospital recidivism rates fell from 79% to 29%, and the average yearly length of hospital stay per patient fell from 83 days to 18 days. In terms of cost-effectiveness, halfway house benefits saved the insurers 59% of their hospitalization costs. The implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Free fatty acid inhibition of the insulin induction of glucose-6-phosphate dehydrogenase in rat hepatocyte monolayers

Rat hepatocytes in monolayer culture were utilized to determine if the decrease in glucose-6-phosphate dehydrogenase (G6PD) activity resulting from the ingestion of fat can be mimicked by the addition of fatty acids to a chemically, hormonally defined medium. G6PD activity in cultured hepatocytes was induced several-fold by insulin. Dexamethasone or T3 did not amplify the insulin induction of G6PD. Glucose alone increased G6PD activity in cultured hepatocytes from fasted donors by nearly 500%. Insulin in combination with glucose induced G6PD an additional two-fold. The increase in G6PD activity caused by glucose was greater in hepatocytes isolated from 72 hr-fasted rats as compared to fed donor rats. Such a response was reminiscent of the “overshoot” phenomenon in which G6PD activity is induced well above the normal level by fasting-refeeding rats a high glucose diet. Addition of linoleate to the medium resulted in a significant suppression of insulin’s ability to induce G6PD, but linoleate had no effect on the induction of G6PD activity by glucose alone. A shift to the right in the insulin-response curve for the induction of G6PD also was detected for the induction of malic enzyme and acetyl-CoA carboxylase. Arachidonate (0.25 mM) was a significantly more effective inhibitor of the insulin action than linoleate was. Apparently rat hepatocytes in monolayer culture can be utilized as a model to investigate the molecular mechanism by which fatty acids inhibit the production of lipogenic enzymes. In part, this mechanism of fatty acid inhibition involves desensitization of hepatocytes to the lipogenic action of insulin.     

Antidepressant pharmacotherapy helps some cigarette smokers more than others.

Adult smokers (N?=?253) without clinically significant depression were randomized on a double-blind basis to receive fluoxetine (30 or 60 mg daily) or a placebo for 10 weeks in combination with cognitive-behavioral therapy (CBT). It was predicted that fluoxetine would selectively benefit smokers with higher baseline depression, nicotine dependence, and weight concern and lower self-efficacy about quitting smoking. Among those who completed the prescribed treatment regimen, baseline depression scores moderated the treatment response. Logistic regression analyses showed that 1 and 3 months after the quit date, fluoxetine increased the likelihood of abstinence, as compared with placebo, among smokers with minor depression but not among those with little or no depression. Results suggest that, as an adjunct to CBT, fluoxetine enhances cessation by selectively benefiting medication-compliant smokers who display even subclinical levels of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychology interns as patient suicide survivors: Incidence, impact, and recovery.

The authors investigated incidence, impact, and methods of coping with patient suicide during the training years of psychology graduate students. All 54 interns in clinical psychology at the Boston VA in 1983–1988 were surveyed. One in 6 Ss had experienced a patient's suicide at some time during their training. The group who experienced a patient's suicide and a group who experienced a patient's suicide attempt both reported high levels of stress on the Impact of Event Scale. Trainees with patient suicides reported stress levels equivalent to that found in patient samples with bereavement and higher than that found with professional clinicians who had patient suicides. Trainees most frequently turned to supervisors for both support and formulation of the suicide. Preparatory efforts at suicide education were found to be minimal and inadequate. Recommendations for assisting the trainee who experiences a patient's suicide are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of dispositional and situational antecedents in prosocial organizational behavior: An examination of the intended beneficiaries of prosocial behavior.

Research has not adequately separated the factors responsible for prosocial behaviors intended to benefit specific individuals from those intended to benefit an organization. Antecedents of the behavior of 100 secretaries were examined as a function of the beneficiary of the behavior. The value of concern for others and empathy explained significant variance in prosocial behaviors directed only at specific individuals (prosocial individual behavior). Perceptions of reward equity and recognition explained significant variance in behaviors directed only at the organization (prosocial organizational behavior). With these effects removed, the relationship between job satisfaction and prosocial organizational behavior was no longer significant, whereas the relationship between job satisfaction and prosocial individual behavior remained significant. Results suggest that the psychological processes that underlie prosocial behavior are different depending on the beneficiary of the behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)