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101.
Christensen Alan J.; Ehlers Shawna L.; Raichle Katherine A.; Bertolatus J. Andrew; Lawton William J. 《Canadian Metallurgical Quarterly》2000,19(4):348
Improvement in patient quality of life is a central goal of renal transplantation. This study examined the hypothesis that change in depression following transplantation would vary as a function of patient coping preferences. Sixty patients were assessed with the Krantz Health Opinion Survey and the Beck Depression Inventory while on the waiting list for a cadaveric renal transplant. Patients were reassessed approximately 12 months later. Among the 33 patients receiving a transplant during the follow-up period, those with a high preference for health-related information exhibited a substantial reduction in depression. In contrast, patients low in preference for information showed a slight increase in depression. Among the 27 patients who were not transplanted during the follow-up period, preference for information had no effect on depression. Patient differences in preference for behavioral involvement did not exert a significant effect on depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
103.
In 2 experiments, with school-age children and adults, age changes in a line-drawing classification task were explored. Pairs of drawings were presented in Experiment 1. In 1 task, observers indicated whether the drawings were the same or different; in the second, they indicated whether the drawings could be interpreted as parts of the same object. Age differences in response time and accuracy were larger in the second task, pointing to the importance of the interpretation component. In Experiment 2, observers were instructed in 1 of 2 strategies, and the presentation of the 2 drawings was separated by 0–4 s. Instructions to engage in active hypothesis testing improved the performance of younger children more than older children, relative to instructions to simply form clear images of the drawings. Increases in the time interval between drawings made the task more difficult for younger children in both instruction conditions. This implies that younger children were less active in the interval between successive drawings, independent of the specific instructions they were given. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Results of a test of three alternative models of the conditions necessary for employee ownership to positively influence employee attitudes are reported. Based on a study of 37 employee stock ownership plan (ESOP) companies (N of individuals?=?2,804), results support hypotheses for the extrinsic and instrumental satisfaction models. Average company ESOP satisfaction and organizational commitment are high and average company turnover intention is low when the ESOP provides substantial financial benefits to employees, when management is highly committed to employee ownership, and when the company maintains an extensive ESOP communications program. In contrast, the results provide no support for the intrinsic satisfaction model of ESOP effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Glenwick David S.; Brodsky Stanley L.; Franks Cyril M.; Hess Allen K.; Balch Katherine; Frank Jerome B.; Garfield Sol L.; Jason Leonard A. 《Canadian Metallurgical Quarterly》1987,42(4):405
Discusses the factors that should be considered when preparing to edit a high-quality, scholarly psychology book. The issues discussed include the book editor–publisher relationship, the book editor–chapter contributor relationship, and what makes a good final product. Three laws of editing are offered: (1) conceptualize clearly; (2) edit fiercely; and (3) edit for the reader, not the writer. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Nicholas R. Krogman Arlin L. Weikel Nhu Q. Nguyen Katherine A. Kristhart Syam P. Nukavarapu Lakshmi S. Nair Cato T. Laurencin Harry R. Allcock 《应用聚合物科学杂志》2010,115(1):431-437
New biomedically erodible polymer composites were investigated. Polyphosphazenes containing the dipeptide side groups alanyl–glycine ethyl ester, valinyl–glycine ethyl ester, and phenylalanyl–glycine ethyl ester were blended with poly(lactide‐co‐glycolide) (PLGA) with lactic to glycolic acid ratios of 50 : 50 [PLGA (50 : 50)] and 85 : 15 [PLGA (85 : 15)] with solution‐phase techniques. Each dipeptide ethyl ester side group contains two N? H protons that are capable of hydrogen bonding with the carbonyl functions of PLGA. Polyphosphazenes that contain only the dipeptide ethyl ester groups are insoluble in organic solvents and are thus unsuitable for solution‐phase composite formation. To ensure solubility during and after synthesis, cosubstituted polymers with both dipeptide ethyl ester and glycine or alanine ethyl ester side groups were used. Solution casting or electrospinning was used to fabricate polymer blend matrices with different ratios of polyphosphazene to polyester, and their miscibilities were estimated with differential scanning calorimetry and scanning electron microscopy techniques. Polyphosphazenes with alanyl–glycine ethyl ester side groups plus the second cosubstituent were completely miscible with PLGA (50 : 50) and PLGA (85 : 15) when processed via solution‐casting techniques. This suggests that the hydrogen‐bonding protons in alanyl–glycine ethyl ester have access to the oxygen atoms of the carbonyl units in PLGA. However, when the same pair of polymers was electrospun from solution, the polymers proved to be immiscible. Solution‐cast miscible polymer blends were obtained from PLGA (50 : 50) plus the polyphosphazene that was cosubstituted with valinyl–glycine ethyl ester and glycine ethyl ester side groups. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
107.
The development and proliferation of antibiotic resistance in pathogenic, commensal, and environmental microorganisms is a major public health concern. The extent to which human activities contribute to the maintenance of environmental reservoirs of antibiotic resistance is poorly understood. In the current study, wastewater treatment plants (WWTPs) were investigated as possible sources of tetracycline resistance via qualitative PCR and quantitative PCR (qPCR). Various WWTPs and two freshwater lakes were surveyed for the presence of an array of 10 tetracycline resistance determinants (tet(R)): tet(A)-(E), tet(G), tet(M), tet(O), tet(Q), tet(S). All WWTP samples contained more different types of tet(R) genes, as compared to the lake water samples. Gene copy numbers of tet(G) and tet(Q) in these samples were quantified via qPCR and normalized to both the volume of original sample and to the amount of DNA extracted per sample (a proxy for bacterial abundance). Concentrations of tet(Q) were found to be highest in wastewater influent while tet(G) concentrations were highest in activated sludge. Investigation of the effects of UV disinfection on wastewater effluent showed no reduction in the number of detectable tet(R) gene types. 相似文献
108.
109.
Novel photocatalyst-based colourimetric indicator for oxygen: Use of a platinum catalyst for controlling response times 总被引:2,自引:0,他引:2
Andrew MillsAuthor Vitae Katherine LawrieAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):600-605
The preparation and characterisation of a novel, UV-activated, solvent-based, colourimetric indicator for oxygen is described, comprising a redox dye (methylene blue, MB), semiconductor photocatalyst (Pt-TiO2), and a sacrificial electron donor (SED = glycerol), all dispersed/dissolved in a polymer medium (sulfonated polystyrene, SPS). Upon exposure to UVA light, the Pt-TiO2/MB/glycerol/SPS oxygen indicator is readily photobleached as the MB is converted into its oxygen-sensitive, leuco form, LMB. In contrast to its non-platinised TiO2 counterpart (TiO2/MB/glycerol/SPS oxygen indicator), the recovery of the original colour is faster (ca. 1.5 days cf. 5 days at 21 °C). This is due to the catalytic action of the 0.38 wt% platinum loaded onto the semiconductor photocatalyst, TiO2, on the oxidation of the photogenerated LMB by ambient O2. Furthermore, by increasing the level of platinum loading, recovery times can be decreased further; e.g. a Pt-TiO2/MB/glycerol/SPS oxygen indicator with platinum level of 1.52 wt% recovers fully within 12 h. A study of the kinetics of recovery as a function of film thickness revealed the recovery step is not controlled by the diffusion of O2 through the film, but instead dependent upon the slow rate of oxidation of LMB to MB by O2 in the low dielectric polymer encapsulation medium. Other work showed this recovery is only moderately dependant upon temperatures above −10 °C and very sensitive to relative humidity above 30% RH. Potential uses of this UV light activated indicator are discussed briefly. 相似文献
110.
Ingrid M le Roux Karl le Roux W Scott Comulada Erin M Greco Katherine A Desmond Nokwanele Mbewu Mary Jane Rotheram-Borus 《Nutrition journal》2010,9(1):56