The interaction of social skill and organizational support on job performance.

The present study examined the moderating effect of perceived organizational support (POS) on the relationship between social skill and supervisor-rated job performance. On the basis of regulatory and activation models of behavior, the authors argue that low-POS environments activate social skill because they reflect situations in which interpersonal acuity is required to demonstrate effective job performance. Accordingly, the authors hypothesize that social skill is more strongly related to performance among workers reporting low rather than high levels of organizational support. Results of hierarchical moderated multiple regression analyses on data gathered from 2 samples support the hypothesis. These results suggest that the relevance of social skill to job performance may be dependent on contextual cues. Implications for substantive research, strengths and limitations, and directions for future research are offered. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

On classification of multispectral infrared image data

A detector is proposed that is based on a model in which the signal components consist of radiant thermal energy from either the small target or the intense, highly structured background. The resulting statistic is effective in enhancing the target and suppressing cluttered background. Estimation of the system parameters based on stochastic approximation techniques is presented. Simulation results demonstrate the practicality of the proposed detector.     

Factors associated with fecal shedding of verotoxin-producing Escherichia coli O157 on dairy farms.

Fecal samples were collected from 4,361 dairy cows on 91 dairy operations between 26 February and 8 July 1996. Fecal samples were cultured for Escherichia coli O157, and positive isolates were probed for verotoxin-producing genes. A total of 52 (1.2%) fecal samples on 22 (24.2%) operations were positive for verotoxin-producing E. coli O157. Herds in which samples were collected on or after 1 May 1996 were significantly more likely to test positive than herds sampled before that date (odds ratio = 7.7). Herds maintained on farms on which alleyways were flushed with water to remove manure were 8.0 times more likely to have samples test positive for verotoxin-producing E. coli O157 than were herds maintained on farms cleaned by use of other methods of manure removal.     

Obesity among offspring of women with type 1 diabetes

OBJECTIVE: To determine subsequent growth and body composition of children born to women with type 1 diabetes compared with controls. DESIGN: Prospective cohort study. SETTING: Follow-up of offspring born to women with type 1 diabetes and controls from an earlier study of diabetes and lactation. SUBJECTS: Seventeen nondiabetic offspring of women with type 1 diabetes and 18 offspring of control women (age range 5.9 to 9.0 years). OUTCOME MEASURES: Anthropometric measures at follow-up included height, weight, triceps and subscapular skinfold thickness. Information on usual nutrient intakes and physical activity patterns was elicited through questionnaires. Body composition was determined from skinfold thickness measures and bioelectrical impedance analysis. A child was identified as obese if he or she met at least 2 of the following 4 criteria for obesity: (1) weight-for-height equal to or greater than 120% of the National Center for Health Statistics (NCHS) reference median plus triceps skinfold greater than the 85th percentile; (2) body mass index (BMI) greater than the 95th percentile for age and sex; (3) percent body fat (from impedance measures) equal to or greater than 25 for boys and 30 for girls; or (4) percent body fat (from sum of skinfold measures) equal to or greater than 25 for boys and 30 for girls. RESULTS: There were 7 obese children in the type 1 diabetes group and none in the control group (p = 0.007). Obese children did not differ from nonobese children in birth weight, body fat patterning, nutrient intake, physical activity patterns, maternal pregravid weight or blood glucose control during the last trimester of pregnancy. Mothers of obese children, however, had fewer years of education and gained more weight during pregnancy compared with mothers of nonobese children in the type 1 diabetes group (p < 0.05). CONCLUSION: Obesity during childhood is a significant problem among nondiabetic children of women with type 1 diabetes. The association of childhood obesity with lower maternal education and excessive pregnancy weight gain warrants further investigation.     

A comparison of two algorithms for solving closed crack problems

Interface (or joint) elements introduce errors in the computation of the Stress Intensity Factor, and uncertainties in the definition of the ‘slipping’ and ‘stuck’ regions in some fracture problems. The PATH algorithm is free of these disadvantages and displays the maximum error in the results; in a test case it required about 30% more machine time than the fast algorithm of Elvin and Leung.     

Cephalosporin antibiotics accelerate gastric emptying in mice

Gastroparesis is a common debilitating complication in many diabetic patients. While several drugs are available for gastroparesis, many patients are not adequately treated. Many patients do not respond to available drugs or appear to develop tachyphylaxis after an initial response. New agents are needed. Erythromycin is a macrolide antibiotic that accelerates gastric emptying through interaction with motilin receptors. Many antibiotics, like erythromycin itself, have significant gastrointestinal side effects. We investigated the ability of cephalosporin antibiotics to alter gastric emptying in mice by employing phenol red spectrophotometry to monitor gastric emptying. Our results indicate that several cephalosporin antibiotics, particularly cefazolin, accelerate gastric emptying. In some cases these drugs appear more efficacious than either erythromycin or metoclopramide. At very high doses, many drugs, including erythromycin, appear to delay gastric emptying. We hypothesize that the gastrointestinal side effects of nausea and vomiting may result from delayed gastric emptying occurring at high doses while lower doses are prokinetic in the stomach.     

Running in the real world: adjusting leg stiffness for different surfaces

A running animal coordinates the actions of many muscles, tendons, and ligaments in its leg so that the overall leg behaves like a single mechanical spring during ground contact. Experimental observations have revealed that an animal's leg stiffness is independent of both speed and gravity level, suggesting that it is dictated by inherent musculoskeletal properties. However, if leg stiffness was invariant, the biomechanics of running (e.g. peak ground reaction force and ground contact time) would change when an animal encountered different surfaces in the natural world. We found that human runners adjust their leg stiffness to accommodate changes in surface stiffness, allowing them to maintain similar running mechanics on different surfaces. These results provide important insight into mechanics and control of animal locomotion and suggest that incorporating an adjustable leg stiffness in the design of hopping and running robots is important if they are to match the agility and speed of animals on varied terrain.     

Salvage angiogenesis induced by adenovirus-mediated gene transfer of vascular endothelial growth factor protects against ischemic vascular occlusion

PURPOSE: Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis, and transgene expression from adenovirus vectors can provide in vivo delivery of proteins. On the basis of this knowledge, we hypothesized that local administration of a replication-deficient adenovirus vector expressing complementary DNA for VEGF (AdVEGF) would induce collateral vessel formation in the setting of ischemia that could protect against subsequent acute vascular occlusion. METHODS: Hindlimb ischemia was induced in Sprague-Dawley rats by means of unilateral ligation of the common iliac artery immediately followed by administration of 4 x 10(9)-plaque-forming units VEGF, the control vector AdNull, or phosphate-buffered saline solution into the iliofemoral adipose tissue and thigh muscles. Untreated rats with common iliac ligation were used as an additional control group. RESULTS: Local VEGF expression was observed for 5 days in AdVEGF-treated rats but not in controls. Three weeks after ligation and vector administration, the ipsilateral femoral artery was ligated for a model of an acute vascular occlusion in the setting of preexisting ischemia. Blood flow to the ischemic hindlimb relative to the contralateral hindlimb evaluated with color microspheres demonstrated significantly increased blood flow in the AdVEGF-treated rats compared with each control group (p < 0.0001). Relative blood flow assessed by means of 99mTc-sestamibi radionuclide scans also demonstrated increased blood flow to the ligated hindlimb of AdVEGF-treated rats compared with each control group (p < 0.002). AdVEGF-treated rats also demonstrated increased vascularity in the ligated limb compared with each control group as assessed by means of angiography (p < 0.0001) and histologic quantification of blood vessels less than 80 microm diameter in local adipose tissue and capillaries per muscle fiber (p < 0.0002). AdVEGF treatment prevented a rise in femoral venous lactate femoral venous concentrations 1 hour after femoral artery ligation in control rats (p < 0.04). CONCLUSIONS: An adenovirus vector expressing VEGF complementary DNA is capable of stimulating an angiogenic response that protects against acute vascular occlusion in the setting of preexisting ischemia, suggesting that in vivo gene transfer of VEGF complementary DNA might be useful in prophylaxis of advancing arterial occlusive disease.