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101.
Nearly one‐half of the industrial engineering undergraduate interviewees in an investigation of their degree program indicated they previously had been enrolled in another major. Understanding why these students chose to remain in or enter a science, technology, engineering and math (STEM) major when their previous choice lost its appeal is an important piece of the STEM participation puzzle. Our data indicate effective formal and informal recruiting, contact with dynamic individuals who conveyed commitment to and excitement about the department and program, and a department that welcomed immigrants and promoted a clear, relevant image of its discipline's identity, influenced student decisions to relocate within STEM rather than attrite. The high proportion of females within the immigrant students is one factor contributing to the department's attainment of sex parity. Our students' stories offer lessons to other departments for attracting and retaining students who enter the higher education STEM pipeline.  相似文献   
102.
OBJECTIVE: There is substantial evidence demonstrating the aggravating effect of human immunodeficiency virus (HIV) infection on the progression of chronic hepatitis C virus (HCV) infection. There is however, little data on the affect of certain factors which could affect liver pathology findings in patients with concomitant HIV infection such as the duration of HIV infection or T-cell subpopulation counts. We examined pathology findings in patients with concomitant HIV and HCV infections to determine the impact of immunodepression. PATIENTS AND METHODS: We reviewed liver pathology data collected in patients with concomitant HIV and HCV infections grouping patients according to severity of the liver pathology: group 1 = cirrhosis or active hepatitis; group 2 = minimally active hepatitis or histologically normal liver. Transparietal liver biopsies were obtained for the work-up of viral hepatitis or because of long-term unexplained fever or suspected lymphoma. Epidemiological and biological data were obtained from medical files. The duration of the liver disease was estimated from the date of exposure to risk of immunodepression as determined by the peripheral CD4+ and CD8+ counts. All pathology specimens were read by two pathologists who established the Knodell score for each patient. RESULTS: Fifty patients were included: 23 were classed in group 1 and 28 in group 2. The Knodell score was significantly different between the two groups, 11 +/- 4 and 4 +/- 3 respectively (p < 0.0001). Disease duration was similar for the two groups: mean 8 years. Mean CD4+ count was significantly higher in group 1: 312/mm3 versus 110/mm3 for group 2 (p = 0.0057); as was the mean CD8+ count (758/mm3 versus 360/mm3, p = 0.0013). For the entire study population, there was a significantly negative correlation (p < 0.05) between the Knodell score and the CD4+ count (r = 0.31) and for the CD8+ count (r = 0.41). CONCLUSION: HCV-related liver pathology in patients co-infected with HIV depends on the level of immunodepression. CD8+ counts are better correlated with pathology findings than with CD4+ counts.  相似文献   
103.
In order to have a reliable and reproducible source of soluble human interferon-gamma (HuIFN-gamma) receptor at our disposal both for studying binding phenomena and for evaluating its neutralizing potential towards the cytokine, we expressed the extracellular part of the receptor in J558L mouse myeloma cells as a fusion protein with the C-terminal c-myc TAG (HuECR-gamma-TAG). It is expected that the receptor will undergo post-translational modifications comparable to that in humans. The affinity purified soluble receptor was subjected to mass spectrometry analysis resulting in a molecular size of 31 to 40 kDa and showed heterogeneous N-glycosylation with an M(r)-contribution of 4 to 13 kDa. Its HuIFN-gamma binding affinity, determined by real time biospecific interaction (BIAcore) analysis, resulted in a value of Kd = 2 x 10(-9) M, which is in agreement with the high affinity described for the cell anchored complete HuIFN-gamma receptor (Kd = 5-35 x 10(-9) M). HuECR-gamma-TAG was able to neutralize the biological activity of HuIFN-gamma in an in vitro antiviral assay. Furthermore, we report for the first time the association and dissociation rate constants, which were, respectively, 2.4 x 10(5) M-1 s-1 and 4.8 x 10(-4) s-1. In conclusion, this mammalian source of the extracellular soluble HuIFN-gamma receptor represents a valuable tool for extensive in vitro studies of the HuIFN-gamma receptor interaction. Furthermore, in view of its expected low or nonimmunogenicity it opens new ways for immunomodulation in vivo.  相似文献   
104.
Former neuropsychological studies with Chronic Fatigue Syndrome (CFS) patients evaluated a broad range of cognitive functions. Several, but not all, reported subtle attentional and memory impairments suggesting possible mild cerebral involvement. In this study, a battery of attentional tests and a verbal memory task were administered to 20 CFS patients and 22 healthy controls (HC) in order to clarify the specific nature of attention and memory impairment in these patients. The results provide evidence for attentional dysfunction in patients with CFS as compared to HC. CFS patients performed more poorly on a span test measuring attentional capacity and working memory. Speeded attentional tasks with a more complex element of memory scanning and divided attention seem to be a sensitive measure of reduced attentional capacity in these patients. Focused attention, defined as the ability to attend to a single stimulus while ignoring irrelevant stimuli, appears not to be impaired. CFS patients were poorer on recall of verbal information across learning trials, and poor performance on delayed recall may be due to poor initial learning and not only to a retrieval failure.  相似文献   
105.
This article describes a second treatment-outcome study of cognitive trauma therapy for battered women with posttraumatic stress disorder (PTSD; CTT-BW). CTT-BW includes trauma history exploration: PTSD education; stress management; exposure to abuse and abuser reminders; self-monitoring of negative self-talk; cognitive therapy for guilt; and modules on self-advocacy, assertiveness, and how to identify perpetrators. One hundred twenty-five ethnically diverse women were randomly assigned to immediate or delayed CTT-BW. PTSD remitted in 87% of women who completed CTT-BW, with large reductions in depression and guilt and substantial increases in self-esteem. White and ethnic minority women benefited equally from CTT-BW. Similar treatment outcomes were obtained by male and female therapists and by therapists with different levels of education and training. Gains were maintained at 3- and 6-month follow-ups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
The authors examined memory compensation techniques used by older adults from 2 memory status groups, not impaired control (NIC) and mild memory deficit (MMD), both at baseline and across a 6-year (3-wave) interval. The groups were derived from a parent sample of 55- to 85-year-old adults from the Victoria Longitudinal Study (NIC baseline, n = 276; memory > parent sample mean; MMD baseline, n = 79; memory > 1 standard deviation below parent sample mean). Multilevel modeling was used to test 3 research questions concerning differences in initial use of, and 6-year changes and variability in, memory compensation. Initial group differences were observed for both a memory compensation technique and a general compensation indicator. Significant differences in 6-year change patterns were observed for 2 memory compensation techniques (recruitment of human memory assistance, investment of extra effort in memory tasks). Interactions of group status and wave showed that older adults with MMD declined in their use of memory compensation strategies, whereas initially NIC older adults increased their use of compensatory techniques over the 6 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
Results from this laboratory have shown that bone metabolism is directly related to extracellular pH and that high concentrations of tobramycin released from impregnated polymethylmethacryrate (PMMA) beads has pH-dependent toxic effects on bone. In the present study, beneficial effects of calcium hydroxide-impregnated PMMA were investigated regarding tobramycin toxicity and bone metabolism in chick embryo tibiae in vitro. Also using Ca(OH)2 as a pH regulator, the antibiotic efficacy of tobramycin-impregnated PMMA was evaluated with respect to inhibition of Staphylococcus aureus growth. When Ca(OH)2 was added to PMMA beads containing tobramycin, the beads released hydroxyl and calcium ions into the culture medium and released more antibiotic than beads containing only tobramycin. Bone metabolism (glycolysis, total protein synthesis, and collagen synthesis) was enhanced by Ca(OH)2-impregnated beads with or without tobramycin. Additionally, bacterial growth was inhibited more strongly when S. aureus was incubated with tobramycin- and Ca(OH)2-impregnated PMMA disks than with disks containing only tobramycin. This study demonstrates the feasibility of adding Ca(OH)2 to tobramycin-impregnated PMMA beads as a regulator of local pH and a promoter of bone metabolism for protection of bone when high concentrations of tobramycin are used to treat osteomyelitis. It also suggests that lower concentrations of antibiotic may be effective if Ca(OH)2 and tobramycin are administered simultaneously.  相似文献   
108.
During the past decade, government agencies have struggled to adequately respond to emergency events that require labor, materials, equipment, and services provided by construction contractors. In fact, the criticism directed at government agencies during their response to, and recovery after, recent events is a testament to the insufficient contracting strategies that were implemented. Countless media headlines highlighted the fragmented approach used to hire contractors expeditiously, and several agencies were criticized for their inconsistent contracting methods. As a result, a study was initiated to investigate the differences between normal federal contracting procedures, as outlined in the Federal Acquisition Regulation (FAR), and emergency acquisition procedures that are permitted by the FAR. The study found six examples of waivers to the usual regulations or expedited contracting techniques permitted by the FAR. Furthermore, the study highlighted five emergency contract strategies that are available to the Navy (as one example of a government agency with contracting authority) and may be available to other governmental contracting authorities as well. Consequently, the purpose of this paper is to identify emergency contract strategies that can be used by government agencies and to outline the criteria that must be met to use each strategy.  相似文献   
109.
Objective: Relationship maintenance strategies help to ensure the continuation of valued relationships by keeping them at a certain level of intimacy. This study evaluated how lung cancer patients' and spouses' efforts to maintain their relationships affected their psychological and marital adjustment over time. Design: Psychosocial questionnaires were administered within 1 month of lung cancer treatment initiation (baseline) and 3 and 6 months later to 158 lung cancer patients and their spouses. Main Outcome Measures: Study outcomes were global severity index scores on the Brief Symptom Inventory, and total scores on the Dyadic Adjustment Scale. Results: Multilevel modeling analyses using the Actor-Partner Interdependence Model showed that, regardless of gender or social role (i.e., patient or spouse), individuals who engaged in the strategies of positivity, networks, and shared tasks reported less distress at baseline than other participants. Over time, the effects of providing more assurances and experiencing a partner's increased reliance on social networks differed: patient distress was exacerbated, and spouse distress was alleviated. Couples where both partners engaged in more frequent maintenance behaviors reported greater dyadic adjustment at baseline and over time. Conclusion: For couples coping with lung cancer, the initial treatment period may be an important time that sets the tone for future spousal interactions. Engaging in relationship maintenance during this stressful time may help mold more resilient relationships and facilitate adjustment as the disease progresses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Examines the content of school psychology books published between 1970 and 1985. The process of historical review reveals recent trends that have their genesis in both internal professional developments and external social, political, and legal pressures on the field. Perspectives on the current status and potential future of the profession of school psychology, as derived from the literature, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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