Performance of drywall shear walls: UC Irvine and CSU San Jose tests

A wealth of data has become available since 2001 about the performance of drywall shear walls under cyclic loading. Drywalls and stucco are the only earthquake lateral force‐resisting system in many existing residential buildings, especially single‐family homes built in the 1970s and earlier. This paper takes a closer look at the actual laboratory cycle‐by‐cycle data from three test programs and uses them to clarify the meaning of significant damage in regard to gypsum‐sheathed shear walls. This paper can be viewed as an extension of the valuable information in the reports by the original authors with a focus on the interpretation and use of the test data for the evaluation of damage to existing wood‐frame buildings. Analysis of the data considers the strength loss observed between the initial and later cycles when the wall is loaded to a certain displacement and shows that a loss of strength does occur. In this regard the paper can also be valuable to others working on performance based design development. The last section of the paper also considers the case where a wall might be repaired after the first cyclic loading protocol and loaded again after the repairs. Copyright © 2008 John Wiley & Sons, Ltd.     

Zolpidem-Related Effects on Performance and Mood During Simulated Night-Shift Work.

The effects of zolpidem, a nonbenzodiazepine hypnotic, on psychomotor task performance, subjective effects, and food intake were examined during simulated shift work. Seven participants completed this 23-day, within-participant design, residential laboratory study. They received a single oral zolpidem dose (0, 5, or 10 mg) 1 hr before bedtime for 3 consecutive days under 2 shift conditions: day shift and night shift. When participants received placebo, next-day performance and subjective effects were disrupted, and food intake was decreased during the night shift. Zolpidem improved subjective reports of sleep quality and, to a lesser extent, next-day performance. Next-day mood, however, was worsened by zolpidem. Food intake was unaffected by zolpidem. These data indicate that shift changes produce performance impairments, mood alterations, and decreases in food intake, and that zolpidem attenuates some shift-change-related disruptions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

p115 RhoGEF, a GTPase activating protein for Galpha12 and Galpha13

Members of the regulators of G protein signaling (RGS) family stimulate the intrinsic guanosine triphosphatase (GTPase) activity of the alpha subunits of certain heterotrimeric guanine nucleotide-binding proteins (G proteins). The guanine nucleotide exchange factor (GEF) for Rho, p115 RhoGEF, has an amino-terminal region with similarity to RGS proteins. Recombinant p115 RhoGEF and a fusion protein containing the amino terminus of p115 had specific activity as GTPase activating proteins toward the alpha subunits of the G proteins G12 and G13, but not toward members of the Gs, Gi, or Gq subfamilies of Galpha proteins. This GEF may act as an intermediary in the regulation of Rho proteins by G13 and G12.     

Staurosporine-induced apoptosis in cardiomyocytes: A potential role of caspase-3

The cloning and sequencing of the genes encoding the translational initiation factors (hIF-2 and heIF-2 gamma) was performed by screening the halophilic archaeon Halobacterium halobium genomic library with a probe constructed from the peptide IGHVDHGK that is conserved in archaeal GTP-binding elongation factors. The codon usage by the hIF-2 and heIF-2 gamma genes showed a preference for triplets ending in G or C. This characteristic is almost identical to that of other H. halobium genes. The translated protein of hIF-2 and heIF-2 gamma genes is made of 414 and 583 amino acid residues, respectively, and contains the sequence motif for the binding of GTP. The sequence of hIF-2 shows a strong similarity to the initiation factor IF-2 from Bacteria whereas heIF-2 gamma shows a strong similarity to the initiation factor eIF-2 gamma from Eucarya.     

Preoperative amiodarone as prophylaxis against atrial fibrillation after heart surgery

BACKGROUND: Atrial fibrillation occurs commonly after open-heart surgery and may delay hospital discharge. The purpose of this study was to assess the use of preoperative amiodarone as prophylaxis against atrial fibrillation after cardiac surgery. METHODS: In this double-blind, randomized study, 124 patients were given either oral amiodarone (64 patients) or placebo (60 patients) for a minimum of seven days before elective cardiac surgery. Therapy consisted of 600 mg of amiodarone per day for seven days, then 200 mg per day until the day of discharge from the hospital. The mean (+/-SD) preoperative total dose of amiodarone was 4.8+/-0.96 g over a period of 13+/-7 days. RESULTS: Postoperative atrial fibrillation occurred in 16 of the 64 patients in the amiodarone group (25 percent) and 32 of the 60 patients in the placebo group (53 percent) (P=0.003). Patients in the amiodarone group were hospitalized for significantly fewer days than were patients in the placebo group (6.5+/-2.6 vs. 7.9+/-4.3 days, P=0.04). Nonfatal postoperative complications occurred in eight amiodarone-treated patients (12 percent) and in six patients receiving placebo (10 percent, P=0.78). Fatal postoperative complications occurred in three patients who received amiodarone (5 percent) and in two who received placebo (3 percent, P= 1.00). Total hospitalization costs were significantly less for the amiodarone group than for the placebo group ($18,375+/-$13,863 vs. $26,491+/-$23,837, P=0.03). CONCLUSIONS: Preoperative oral amiodarone in patients undergoing complex cardiac surgery is well tolerated and significantly reduces the incidence of postoperative atrial fibrillation and the duration and cost of hospitalization.     

Effect of atenolol or metoprolol on waking hour dynamics of the QT interval in myocardial infarction

In subjects with a recent acute myocardial infarction, the hour immediately following awakening is associated with an abrupt exaggeration of heart rate-dependent changes and variability of the QT interval. Beta blockers were observed to blunt these waking hour changes.     

Role of family and peers in the development of prototypes associated with substance use.

Prior research and theory suggest that adolescents often experiment with substances to acquire desired social images. However, little research has addressed the developmental precursors leading to favorable evaluation of substance users. This study tested a model of parental and peer influence on adolescent prototypes using a longitudinal data set of 463 rural adolescents. For both drinking and smoking, positive prototypes of substance users were best predicted by peer affiliations. Adolescents who affiliated with peers who practiced and encouraged substance use developed more positive prototypes of people who drink and smoke. These social images, in turn, predicted subsequent use of alcohol and cigarettes. In contrast to peers, parents had little direct influence on prototypes but did indirectly affect images through the adolescents' choice of peers. Unexpectedly, there was evidence of a negative modeling effect of parental substance use, such that parental smoking predicted more negative prototypes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How well do people recall risk factor test results? Accuracy and bias among cholesterol screening participants.

The authors conducted a community-based cholesterol screening study to examine accuracy of recall for self-relevant health information in long-term autobiographical memory. Adult community residents (N = 496) were recruited to participate in a laboratory-based cholesterol screening and were also provided cholesterol counseling in accordance with national guidelines. Participants were subsequently interviewed 1, 3, or 6 months later to assess their memory for their test results. Participants recalled their exact cholesterol levels inaccurately (38.0% correct) but their cardiovascular risk category comparatively well (88.7% correct). Recall errors showed a systematic bias: Individuals who received the most undesirable test results were most likely to remember their cholesterol scores and cardiovascular risk categories as lower (i.e., healthier) than those actually received. Recall bias was unrelated to age, education, knowledge, self-rated health status, and self-reported efforts to reduce cholesterol. The findings provide evidence that recall of self-relevant health information is susceptible to self-enhancement bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)