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101.
When blood comes into contact with an artificial surface, a number of events occur which include protein adsorption, platelet activation and the activation of the intrinsic pathway of blood coagulation. With the increased application of blood containing artificial devices, there is a great demand to develop new biomaterials which retard thrombus formation. Our new approach to solving this problem is to mimic the non-thrombogenic surface of natural biological membranes at least in a simple form. We have developed a polymerisable phospholipid and polyesters based on the major phospholipid polar head group present on the erythrocyte outer membrane surface. The coagulation of blood exposed to these polymers was examined by the technique of Material Thrombelastography, a relatively simple test for the in vitro screening of polymer thrombogenicity. We present results which indicate that the polymerised phospholipid and polyesters show reduced thrombogenicity, and may therefore have potential for future biomaterials. 相似文献
102.
Performed a cluster analysis of therapeutic approaches in clinical training on the basis of data provided in a survey conducted by G. Colletti et al (1983) of program directors of 96 clinical psychology training programs. Support was found for the emerging popularity of eclectic and cognitive behavioral training approaches in academic clinical psychology. The analysis revealed 3 relatively discrete clusters and 1 heterogeneous grouping: eclectic/cognitive-behavioral (n?=?59); broad-spectrum behavioral (n?=?13); psychoanalytic/humanistic (n?=?8); and unclassified (n?=?16). Psychoanalytically oriented training programs tended to be concentrated in large urban settings. It is suggested that the adoption of eclectic and cognitive behavioral approaches among clinical practitioners may be expected to grow as graduates of training programs emphasizing such orientations enter the field. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Microdielectrometry has been used to follow the cure kinetics of interpenetrating polymer networks (IPNs). The rate of formation of a polyurethane–poly(n-butyl acrylate) IPN has been characterized at three temperatures. The dielectric data indicate that the relative homonetwork formation rates dominate the resultant material properties. 相似文献
104.
Although several psychological theories predict that members of stigmatized groups should have low global self-esteem, empirical research typically does not support this prediction. It is proposed here that this discrepancy may be explained by considering the ways in which membership in a stigmatized group may protect the self-concept. It is proposed that members of stigmatized groups may (a) attribute negative feedback to prejudice against their group, (b) compare their outcomes with those of the ingroup, rather than with the relatively advantaged outgroup, and (c) selectively devalue those dimensions on which their group fares poorly and value those dimensions on which their group excels. Evidence for each of these processes and their consequences for self-esteem and motivation is reviewed. Factors that moderate the use of these strategies and implications of this analysis for treatment of stigmas are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
The underrepresentation of women in engineering typically is explained by gender differences in occupational interests, attitudes, or abilities. This paper examines the gender differences hypothesis as well as anticipated role conflicts of women and men students. We explore the academic, career, and family attitudes and expectations of women and men majoring in engineering. Men and women are remarkably similar in their abilities, academic experiences, and career influences. Women, however, are more likely to anticipate that lack of confidence in their own abilities and conflicts between work and family responsibilities will be barriers to success in their careers. These differences, along with several differences in orientations toward family roles, suggest that a role conflict argument better accounts for the disparity in the career development of men and women engineers. Suggestions for addressing these role conflicts before women begin working as engineers are provided. 相似文献
106.
Paul H. Falcone Aaron C. Tribby Roxanne M. Vogel Jordan M. Joy Jordan R. Moon Chantelle A. Slayton Micah M. Henigman Joanne A. Lasrado Brandon J. Lewis Brenda A. Fonseca Kristin M. Nieman Kelli A. Herrlinger 《Journal of the International Society of Sports Nutrition》2018,15(1):58
Background
Proprietary spearmint extract (PSE) containing a minimum 14.5% rosmarinic acid and 24% total phenolic content, has evinced positive effects on cognition in individuals aged 50–70 with memory impairment after chronic supplementation. To address the growing interest in connecting mental and physical performance, the present study examined whether the nootropic effects of PSE translate into changes in reactive agility following daily supplementation with PSE.Methods
Utilizing a randomized, double-blind, placebo-controlled, parallel design, healthy, recreationally-active men and women (n?=?142) received 900?mg of PSE or placebo (PLA) daily for 90?days. Reactive agility, our primary outcome, was determined by measuring the number of hits and average reaction time (ART) on a Makoto Arena II, a 3600 audio-visual device that measures stationary, lateral, and multi-directional active choice reaction performance. Safety was evaluated using complete blood count, comprehensive metabolic panel, and blood lipids. Measurements were evaluated on days 7, 30, and 90 of supplementation.Results
An overall treatment effect (p?=?0.019) was evident for increased hits with PSE on the stationary test with footplates, with between group differences at Day 30 (PSE vs. PLA: 28.96?±?2.08 vs. 28.09?±?1.92 hits; p?=?0.040) and Day 90 (PSE vs. PLA: 28.42?±?2.54 vs. 27.02?±?3.55 hits; p?=?0.002). On the same task, ART improved (treatment effect, p?=?0.036) with PSE at Day 7 (PSE vs. PLA: 0.5896?±?0.060 vs. 0.6141?±?0.073?s; p?=?0.049) and Day 30 (PSE vs. PLA: 0.5811?±?0.068 vs. 0.6033?±?0.055?s; p?=?0.049). PSE also significantly increased hits (treatment effect, p?=?0.020) at Day 30 (PSE vs. PLA: 19.25?±?1.84 vs. 18.45?±?1.48 hits; p?=?0.007) and Day 90 (PSE vs. PLA: 19.39?±?1.90 vs. 18.66?±?1.64 hits; p?=?0.026) for the multi-directional test with footplates. Significant differences were not observed in the remaining Makoto tests. PSE was well tolerated as evidenced by no effects observed in the blood safety panels.Conclusions
The findings of the current study demonstrate that consumption of 900?mg of PSE improved specific measures of reactive agility in a young, active population.Trial registration
clinicaltrials.gov, NCT02518165. Registered August 7, 2015 – retrospectively registered.107.
Christian Franke Olaf Stenzel Steffen Wilbrandt Mark Schürmann Josephine Wolf Vera Todorova Brenda Doherty Prof. Dr. Norbert Kaiser 《真空研究与实践》2016,28(1):28-32
Determination of the Optical Constants of Common Substrate Materials in the NIR/MIR‐Spectral Regions An approach is reported for determining the optical constants of substrates and single layer coatings in the near and mid‐infrared spectral regions. A combination of the algorithm from Nichelatti and a multi‐oscillator model has been used to determine the optical constants of the substrates. Thus, the approach even works when the sample transmittance is vanishing. We demonstrate the application of the approach to the evaluation of transmission and reflection spectra of common substrates (CaF2, Q1, Sapphire) measured by a Fourier‐Transform‐Infrared spectrophotometer. The comparison of the calculated optical constants with values reported in literature confirms the validity of the used approach. We also demonstrate the IR characterisation of a tantalum oxide single layer deposited onto a Q1 substrate by means of the multi‐oscillator‐model. The results are again in good agreement with literature data. 相似文献
108.
Leslie S. Ramsammy Brenda Haynes Christine Josepovitz George J. Kaloyanides 《Lipids》1993,28(5):433-439
The purpose of this study was to investigate the roles of decreased synthesis and increased consumption in the depression
of arachidonic acid levels in renal cortex and glomeruli of rats with streptozotocin-induced diabetes mellitus. In diabetic
rats, arachidonic acid was depressed 33.2% in renal cortex, 47.4% in liver and 66.1% in heart compared to values of control
rats. Δ6 Desaturase activity was depressed in renal cortex, liver and heart of diabetic rats to 53.3, 55.5 and 63.7%, respectively,
of control values. Δ5 Desaturase activity was also depressed 43.7, 55.5 and 47.6% in renal cortex, liver and heart of diabetic
rats, respectively. In other rats the activities of five enzymes involved in the synthesis and esterification of arachidonic
acid were measured in renal cortex and in isolated glomeruli. Both tissues from diabetic rats showed depressed activities
of Δ5 and Δ6 desaturases, increased activities of long-chain acyl-CoA synthetase and 1-acyl-sn-glycero-3-phosphocholine acyltransferase and no change in the activity of elongase as compared to those in control tissues.
Malondialdehyde, an end product of lipid peroxidation, was lower in the renal cortex of diabetic rats than in control rats,
whereas β-oxidation of linoleic acid and arachidonic acid were similar in diabetic and in control rats. Basal and stimulated
prostaglandin E2 synthesis were significantly higher in isolated glomeruli from diabetic rats compared to those in control rats. In isolated
tubules, prostaglandin E2 synthesis was similarly low in both groups. From these data we conclude that the reduced level of arachidonic acid esterified
in lipids of the kidney cortex is caused principally by depressed synthesis of arachidonic acid secondary to decreased activity
of Δ5 and Δ6 desaturases. Increased consumption of arachidonic acid to support prostaglandin synthesis may have contributed
to the depression of arachidonic acid in glomeruli but not in tubules. 相似文献
109.
A. Cork D. J. Chamberlain P. S. Beevor D. R. Hall Brenda F. Nesbitt D. G. Campion M. R. Attique 《Journal of chemical ecology》1988,14(3):929-945
Ovipositor washings from virgin femaleEarias vittella (F.) (Lepidoptera: Noctuidae) moths were examined by gas chromatography (GC) linked to electroantennography (EAG). Six components were detected by the male moth. These were identified by comparison of their retention times with those of a range of synthetic standards on fused silica capillary GC columns as hexadecanal, (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, octadecanal, (Z)-11-octadecenal, and (E,E)-10,12-hexadecadien-1-ol in 1210241 ratio. Field testing in Pakistan showed that a 2102 mixture of (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, and (Z)-11-octadecenal was as attractive to maleE. vittella moths as the six-component mixture and equal in attractiveness to a virgin female moth. Omitting (Z)-11-hexadecenal or (Z)-11-octadecenal greatly reduced this attractiveness. It was found that synthetic lures must be protected from sunlight to prevent loss of attractiveness caused by isomerization of the conjugated diene aldehyde, and addition of (E,Z)-10,12-hexadecadienal, one of the products of isomerization, was shown to reduce attractiveness significantly. During this work, a 101 mixture of (E,E)-10, 12-hexadecadienal and (Z)-11-hexadecenal was shown to be as attractive toE. insulana (Boisd.) male moths as a virgin female moth, and the attractiveness of this mixture was further increased by addition of (E,Z)-10,12-hexadecadienal. 相似文献
110.
Brenda Reeb 《国际互联网参考资料服务季刊》2013,18(1-2):1-2
This article presents a systematic review of the current practices of creating, maintaining, using, and evaluating East Asian studies guides across North America. We examined 137 East Asian studies subject guides published by 44 major East Asian libraries and surveyed the East Asian librarian community. In this article, we discuss the common issues and unique challenges faced by East Asian studies librarians and propose recommendations. Our aim is to provide insight for East Asian studies librarians in order to help them better manage their subject guides and serve the evolving needs of users in this digital age. 相似文献