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71.
Vasquez Melba J. T.; Lott Bernice; García-Vázquez Enedina; Grant Sheila K.; Iwamasa Gayle Y.; Molina Ludwin E.; Ragsdale Brian L.; Vestal-Dowdy Elise 《Canadian Metallurgical Quarterly》2006,61(2):157
In this article, six faculty and students of color who participated in a panel discussion at a symposium during the National Multicultural Conference and Summit of 2003 talk about the barriers they encountered and continue to encounter in their graduate training and places of employment. They also discuss strategies they found to be effective, enhancing, and positive and suggest other possibilities. The contributors describe their relationships with dominant-group and minority peers and talk about how issues of social class, disability, and sexual orientation as well as color have been part of their experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
X. Demulsant J. Mendez 《Fatigue & Fracture of Engineering Materials & Structures》1995,18(12):1483-1497
Abstract— The nucleation and growth of small naturally initiated cracks have been investigated on Ti 6 Al 4V alloys, with bimodal or globular microstructures. Tests have been performed in air at a stress amplitude near 0.75 of the yield stress. The influence of microstructure on fatigue damage is described and the differences in fatigue life of some titanium alloys are explained. The effect of microstructure on fatigue resistance is mainly related to the early stages of damage including initiation and small crack growth. Coalescence processes favoured by a high density of initiated surface microcracks in fine α grain material, or rapid initiation of large cracks in coarse α colonies, explains low fatigue resistance or lifetime scattering in globular alloys. Small crack growth retardation due to α/β barriers associated with a low surface crack density, limiting coalescence processes, explains the highest resistance of bimodal structures. 相似文献
73.
Tara J Fano Sheila M Tyminski Mary A T Flynn 《Revue canadienne de la pratique et de la recherche en diététique》2004,65(2):72-80
To evaluate the impact of the Calgary Health Region Collective Kitchen Program on various Population Health Promotion Model health determinants, data were collected through mail-in questionnaires that examined the members' (n=331) and coordinators' (n=58) perspectives of the program. Seventy-nine members (24%) and 26 coordinators (45%) were included in the study. Three incomplete questionnaires (from prenatal program members) were discarded. Sixty-one percent of members who reported income level and family size (n=61) had incomes below the low-income cut-off. Fifty-eight members (73%) reported improvements in their lives because of the program. Sixty-four members (81%) perceived they learned to feed their families healthier foods. The members reported their fruit and vegetable consumption before and since joining a collective kitchen, and the proportion of those consuming at least five fruit and vegetable servings a day rose from 29% to 47%. The most common reasons for joining this program concerned social interactions and support. Over 90% of the coordinators perceived that they were competent to coordinate a kitchen. The results indicate that the collective kitchens program addresses several health determinants, and may increase members' capacity to attain food security and to achieve improved nutritional health. 相似文献
74.
This article discusses a unique teaching internship program that has been in place in the Woodruff School of Mechanical Engineering at Georgia Institute of Technology since 1990. The objective of the program is to provide doctoral students who are considering an academic career an opportunity to gain teaching experience under the tutelage of a faculty member. This article summarizes the major findings from student evaluations and from surveys of former student and faculty participants and discusses the apparent need and benefit of such a doctoral teaching intern program. Benefits and drawbacks of participation are discussed from the intern, faculty mentor, and student points of view. Conclusions are drawn about the overall effectiveness of the program and recommendations are made for implementing a successful teaching internship program. 相似文献
75.
I Vilacosta JA San Román P Aragoncillo J Ferreirós R Mendez C Graupner E Batlle J Serrano A Pinto JM Oyonarte 《Canadian Metallurgical Quarterly》1998,32(1):83-89
The effect of medium pH on the activity of cultured human osteoblasts was investigated in this study. Osteoblasts derived from explants of human trabecular bone were grown to confluence and subcultured. The first-pass cells were incubated in Hepes-buffered media at initial pHs adjusted from 7.0 to 7.8. Osteoblast function was evaluated by measuring lactate production, alkaline phosphatase activity, proline hydroxylation, DNA content, and thymidine incorporation. Changes in medium pH were determined from media pHs recorded at the beginning and end of the final 48 h incubation period. As medium pH increased through pH 7.6, collagen synthesis, alkaline phosphatase activity, and thymidine incorporation increased. DNA content increased from pH 7.0 to 7.2, plateaued from pH 7.2 to 7.6, and increased again from pH 7.6 to 7.8. The changes in the medium pH were greatest at pHs 7.0 and 7.8, modest at pHs 7.4 and 7.6, and did not change at 7.2, suggesting that the pHs are migrating towards pH 7.2. Lactate production increased at pH 7.0 but remained constant from 7.2 to 7.8. These results suggest that in the pH range from 7.0-7.6 the activity of human osteoblasts increases with increasing pH, that this increase in activity does not require an increase in glycolytic activity, and that pH 7.2 may be the optimal pH for these cells. 相似文献
76.
The online version of the original article can be found at 相似文献
77.
Petry Nancy M.; Alessi Sheila M.; Hanson Tressa; Sierra Sean 《Canadian Metallurgical Quarterly》2007,75(6):983
Contingency management (CM) interventions frequently utilize vouchers as reinforcers, but a prize-based system is also efficacious. This study compared these approaches. Seventy-four cocaine-dependent methadone outpatients were randomly assigned to standard treatment (ST), ST plus a maximum of $585 in contingent vouchers, or ST plus an expected average maximum of $300 in contingent prizes for 12 weeks. CM participants achieved longer durations of abstinence (LDA) than ST participants, and CM conditions did not differ significantly in outcomes or amount of reinforcement earned. Although long-term abstinence did not differ by group, LDA during treatment was the best predictor of abstinence at 9 months. Thus, reinforcement with prizes was similar to voucher CM in promoting LDA, which is associated with posttreatment benefits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Reviewed, retrospectively, 30 custody and access dispute cases (8 assessments, 22 arbitrations, and 10 mediations) and analyzed factors associated with each procedure. The factors examined were based on parents' views of their dispute, as recorded in an initial intake questionnaire completed preintervention. Findings suggest that couples who resolve their dispute through mediation tend to be more child-focused, future-oriented, positive about themselves, and helpful in providing suggestions for dispute resolution than parents involved in an assessment process. (French abstract) (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
This paper is concerned with a production planning problem of allocating production items to production shifts on production lines in a multiple objective decision environment. The problem is modeled and solutions are generated using integer goal programming techniques. Objectives are formulated not only in terms of minimizing the sum of deviations from goal target levels, but also in terms of minimizing the maximum deviation. Test results indicate that the model structure and solution process utilized can provide decision makers with a good set of representative solutions in a rather complex multiple objective decision environment. 相似文献
80.
Ernesto H. Perea Emilio Mendez Clifton G. Fonstad 《Journal of Electronic Materials》1980,9(2):459-466
The electron effective mass in InuGa1−uPvAs1−v has been measured on seven samples lattice-matched to InP and evenly spaced in values of v between 0 and 1, using the temperature
dependence of the amplitude of the Shubnikov-de Haas oscillations at high magnetic fields. Values of the carrier concentrations,
Hall mobilities and Dingle temperatures measured on these samples are also reported.
Work sponsored in part by the National Science Foundation, Grant No. ENG 76-09586, and in part by International Telephone
and Telegraph Electro-Optical Products Division. Work done in part at the M.I.T. Francis Bitter National Magnet Laboratory.
Funded in part by the National Science Foundation under Grant No. DMR-76-80895. 相似文献