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81.
82.
Immobilization of lipase B from Candida antarctica on epoxy‐functionalized silica: characterization and improving biocatalytic parameters
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83.
Effects of ventilation rate per person and per floor area on perceived air quality,sick building syndrome symptoms,and decision‐making
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R. Maddalena M. J. Mendell K. Eliseeva W. R. Chan D. P. Sullivan M. Russell U. Satish W. J. Fisk 《Indoor air》2015,25(4):362-370
Ventilation rates (VRs) in buildings must adequately control indoor levels of pollutants; however, VRs are constrained by the energy costs. Experiments in a simulated office assessed the effects of VR per occupant on perceived air quality (PAQ), Sick Building Syndrome (SBS) symptoms, and decision‐making performance. A parallel set of experiments assessed the effects of VR per unit floor area on the same outcomes. Sixteen blinded healthy young adult subjects participated in each study. Each exposure lasted four hours and each subject experienced two conditions in a within‐subject study design. The order of presentation of test conditions, day of testing, and gender were balanced. Temperature, relative humidity, VRs, and concentrations of pollutants were monitored. Online surveys assessed PAQ and SBS symptoms and a validated computer‐based tool measured decision‐making performance. Neither changing the VR per person nor changing the VR per floor area, had consistent statistically significant effects on PAQ or SBS symptoms. However, reductions in either occupant‐based VR or floor‐area‐based VR had a significant and independent negative impact on most decision‐making measures. These results indicate that the changes in VR employed in the study influence performance of healthy young adults even when PAQ and SBS symptoms are unaffected. 相似文献
84.
Decision making in uncertain environments is a daily challenge faced by adults of all ages. Framing decision options as either gains or losses is a common method of altering decision-making behavior. In the experiment reported here, benchmark decision-making data collected in the 1970s by Tversky and Kahneman (1981, 1988) were compared with data collected from current samples of young and older adults to determine whether behavior was consistent across time. Although differences did emerge between the benchmark and the present samples, the effect of framing on decision behavior was relatively stable. The present findings suggest that adults of all ages are susceptible to framing effects. Results also indicated that apparent age differences might be better explained by an analysis of cohort and time-of-testing effects. Actual or potential applications of this research include an understanding of how framing might influence the decision-making behavior of people of all ages in a number of applied contexts, such as product warning interactions and medical decision scenarios. 相似文献
85.
AD Blann M Seigneur M Steiner JP Miller CN McCollum 《Canadian Metallurgical Quarterly》1998,79(6):1080-1085
We examined the relationship of soluble intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) with smoking and hypercholesterolaemia in peripheral artery disease (PAD). Serum samples were obtained from 119 patients with objectively-proven PAD, 39 patients with hypercholesterolaemia but asymptomatic for PAD, and 132 age and sex matched asymptomatic controls. Using ELISAs, we found increased sICAM-1 and sVCAM-1 (both p <0.01) in the patients with PAD relative to the controls, but no significant change in patients with hypercholesterolaemia. However, the effect for sVCAM-1 was lost when smoking was entered as a covariate. Only sICAM-1 was higher in patients with PAD in the femoral/iliac arteries compared to the carotid arteries (p <0.05). In a 39-month follow-up of 112 patients with PAD, increased ICAM-1 weakly (univariate p <0.05) predicted those 57 whose disease progressed (i.e. to end points such as myocardial infarction and arterial surgery). However, high fibrinogen was a much better (univariate p = 0.001, multivariate p <0.05) predictor of disease progression. We suggest (i) that increased levels of sVCAM-1 in atherosclerosis are due to smoking, (ii) that increased sICAM-1 is independent of this risk factor, (iii) that both these changes are independent of hypercholesterolaemia, and (iv) that increased sICAM-1 is a weak predictor of disease progression in peripheral atherosclerosis. 相似文献
86.
AJ Chohan AD Kugelmass M Kida LR Pennington CA Sivaram 《Canadian Metallurgical Quarterly》1998,14(3):463-465
A cardiac transplant recipient with multiple coronary artery fistulae draining into the right ventricle is described. These fistulae presumably resulted from repeated endomyocardial biopsies. The diagnosis of coronary artery fistulae was made at the annual coronary arteriography. The magnitude of the shunt remained small over eight years of follow-up. 相似文献
87.
Human females have been reported to be uniquely sensitive to the deleterious effects of ethanol, thus it is important to study the characteristics of and mechanisms underlying alcohol consumption that may be specific to females. Models of ethanol self-administration in female rats that take into consideration the estrous cycle have the potential to provide important information concerning these characteristics and mechanisms. The purpose of this study was to explore the effect of the cycle on ethanol self-administration using a limited access operant paradigm. Female Wistar rats were trained to lever press for 10% ethanol versus water using a saccharin fading procedure. Responses were examined across the four phases of the estrous cycle. No effects of estrous cycle phase were observed when these rats were allowed to cycle freely. Subsequently, estrous phase effects were investigated in females whose cycles had been synchronized. Under this condition, an effect of estrous phase was present, with lower ethanol intake observed in estrus (and in some cases proestrus). Synchronized rats all showed at least one very clear 4-day estrous cycle, whereas free-running rats' cycles ranged from 3 to 5 days. Thus, it is more likely that synchronized rats were tested in the identical portion of each phase, when hormone levels were less variable. These results suggest that ethanol may be more reinforcing during diestrus than proestrus and estrus in female rats. 相似文献
88.
G Chow IG Roberts P Fallon M Onoe A Lloyd-Thomas MJ Elliott AD Edwards FJ Kirkham 《Canadian Metallurgical Quarterly》1997,11(4):633-639
BACKGROUND: The precise mechanisms involved in islet xenograft rejection remain unknown. The purpose of the present study was to determine cellular mechanisms responsible for islet xenograft rejection in the liver to facilitate finding a procedure for prevention of immune rejection. METHODS: Hepatic mononuclear cells (MNC) as well as splenocytes, peripheral blood MNC, and thymocytes from streptozotocin-induced diabetic mice (BALB/c) rejecting the intrahepatic rat (Lewis) islet xenografts were isolated and examined by two-color FACS analysis. RESULTS: The characteristic finding of the hepatic MNC from the mice rejecting islet xenografts compared with mice receiving isografts was a significant increase in the yield as well as in the percentage of the cells expressing CD3+ interleukin-2 receptor (IL-2R) alpha- beta+, CD3+ CD8alpha+ beta+, and T cell receptor (TCR) alphabeta+ lymphocyte function-associated antigen-1+. The expression of CD3 and TCR alphabeta of these T cells was found to be of intermediate intensity (TCR(int) cells). The expansion of these TCR(int) cells occurred predominantly in the liver. There was no significant difference in the cells expressing CD3+ IL-2R alpha+, CD3+ CD4+, CD3+ TCRgammadelta+, CD3- IL-2Rbeta+ (natural killer cells), and B220+ (B cells). In vivo administration of anti-IL-2Rbeta monoclonal antibody directed to the expanded cells produced a prevention of rejection. CONCLUSIONS: These findings suggest that islet xenograft rejection in the liver from rat to mouse is an event for which the TCR(int) cells are responsible. 相似文献
89.
EA Geiser DC Wilson DX Wang DA Conetta JD Murphy AD Hutson 《Canadian Metallurgical Quarterly》1998,11(4):338-348
An autonomous endocardial and epicardial boundary detection (ABD) method is reported. One hundred ten cycles from 55 clinical studies were selected retrospectively. Image sequences were digitized at 512 x 480 pixel resolution. The point-by-point boundary positions of the ABD and the areas enclosed were compared with positions and enclosed areas drawn by three independent observers. Correlation coefficients for epicardial end-diastolic (ED) and end-systolic (ES) areas, endocardial ED and ES areas, muscle area, and fractional area change were 0.970, 0.976, 0.951, 0.985, 0.887, and 0.878, respectively. Bland-Altman analysis showed negligible biases with standard deviations comparable to those of the observers. The mean difference between the ABD border and the consensus observer border positions in 64 directions falls within the mean range of interobserver border positions, suggesting that shape is also well defined by the ABD. 相似文献
90.
Whole-cell patch-clamp recordings were used to characterize the membrane properties and ion channel complement of floor plate neuroepithelia in embryonic and neonatal rats. The average resting potential was close to -60 mV, the capacitance was approximately 7 pS and the membrane time constant averaged 31 ms, in both neonates and embryos. Two types of K+ current were identified (i) a slowly activating, slowly inactivating current that was present in all cells, and (ii) a rapidly inactivating current that was present in 39% of cells from neonates and 64% of cells from embryos. K+ currents were significantly larger in neonates than embryos. Na+ currents were absent from all neuroepithelial cells examined. In contrast, the majority of floor plate cells exhibited a significant Ca2+ current. Biophysically this current activated at potentials positive to 60 mV and exhibited fast, voltage-dependent, inactivation. The Ca2+ current was equipermeant to Ca2+ and Ba2+, sensitive to 40-120 microM Ni2+ and only slightly inhibited by 100 microM Cd2+. These and other observations indicated this current is mediated by low-voltage-activated (i.e. T-type) Ca2+ channels. The majority of floor plate cells tested also exhibited responses to the neurotransmitter GABA which produced robust inward currents at negative membrane potentials, in chloride-loaded cells. Both the pharmacology and voltage-dependence of the GABA-activated currents indicated they arose from activation of GABA(A) receptors. 相似文献