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991.
A kinetics of the chemical vapor deposition (CVD) of copper using novel unfluorinated precursor, copper(I)(N(1(dimethylvinylsiloxy)-1-methylethano)-2-imino-4-pentanoate), namely Cu-KI5, was studied. Since its great thermal stability, Cu-KI5 allowed high source temperature to provide high vapor pressure, for example Cu-KI5 has a vapor pressure of 0.2-2.2 Torr at the temperature range of 100-140 °C. Furthermore, copper could be deposited by direct reduction from Cu-KI5 instead of disproportionation. By using formic acid (HCOOH) as a reducing agent, copper films were deposited on ruthenium substrate at temperature range of 150-350 °C. The activation energy was 48.9 kJ/mol in surface reaction limited region (<210 °C) and 1.9 kJ/mol in diffusion limited region (>210 °C) at the total pressure of 5 Torr. Secondary ion mass spectroscopy (SIMS) analysis showed that CVD copper film of high purity (>99.99%) was deposited at 250 °C. The as-deposited copper films grown at 150-300 °C exhibited strong 〈111〉 preferred orientation. The minimum resistivity of the copper film was 1.77 μΩ cm obtained at the deposition temperature of 250 °C. In the surface reaction limited region, kinetic data extracted from experiments enabled 2-D computational simulation to predict copper deposition into trench structures. Simulation results showed excellent step coverage, which was larger than 90% for aspect ratio of 10:1. Cu-KI5 is a promising Cu-CVD precursor for the fabrication of ultra large scale integration (ULSI) or through silicon via (TSV) copper interconnects.  相似文献   
992.
Recommended drying treatments may not enhance destruction of pathogens that could be present on home-dried foods. In this study, the effects of traditional and modified treatments on Salmonella were evaluated during preparation, home-type dehydration (60 degrees C for 6 h), and storage of potato slices. Potato slices inoculated with five strains of Salmonella (8.4 log CFU/ g) were left untreated or were treated by steam blanching (88 degrees C for 10 min), water blanching (88 degrees C for 4 min), 0.105% citric acid blanching (88 degrees C for 4 min), or 0.210% citric acid blanching (88 degrees C for 4 min). Slices were then dried (6 h for 60 degrees C) and aerobically stored for up to 30 days at 25 +/- 3 degrees C. Cells were enumerated on tryptic soy agar with 0.1% pyruvate (TSAP) and on xylose lysine deoxycholate agar. Salmonella populations were reduced by 4.5 to 4.8 CFU/g and by >5.4 log CFU/g immediately following steam and water blanching, respectively. Populations were below the detection limit (0.80 log CFU/g) immediately following acid blanching, except for samples blanched in 0.105% citric acid and recovered on TSAP. After dehydration (6 h for 60 degrees C), Salmonella reductions on blanched potato slices (5.3 to 5.6 log CFU/g) were significantly greater (P < 0.05) than those on untreated samples (1.9 to 2.7 log CFU/g). Populations on all samples continued to decrease throughout 30 days of storage but still were 3.1 to 3.9 log CFU/g on untreated samples. In comparison, bacterial populations on blanched samples were undetectable by direct plating following 30 days of storage (regardless of blanching method). Blanching treatments used in this study improved the effectiveness of drying for inactivating Salmonella inoculated onto potato slices and, therefore, may enhance the safety of the product.  相似文献   
993.
A primary mechanistic hypothesis by which ambient air particles have a significant negative impact on human health is via the induction of pulmonary inflammatory responses mediated through the generation of reactive oxygen species (ROS). Development of a biosensor for the assessment of particulate ROS activity would be a significant advance in air pollution monitoring. The objective of this study was to evaluate whether air particulates interact directly with protective enzymes involved in oxidative stress responses. We performed enzyme activity assays on four enzymes involved in oxidative stress responses (Cu/Zn superoxide dismutase, Mn superoxide dismutase, glutathione peroxidase, and glutathione reductase) in the presence of particles of varying toxicities and found distinctive inhibition patterns. On the basis of these findings, we suggest a strategy for an enzyme bioassay that could be used to assess the potential of particles to generate ROS-induced responses.  相似文献   
994.
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   
995.
IT systems for engineers are becoming more numerous and complex and will further proliferate in the future. It is infeasible to expect users to be trained to work with a plethora of systems, especially as many of them will only see occasional use. Therefore, in the near future, systems will need user interfaces that allow intuitive access and usage. This paper examines a new style of user interface based on virtual reality.  相似文献   
996.
Stigma theory was used to examine the fears underlying the disclosure of a gay identity at work. Using a national sample of 534 gay, lesbian, and bisexual employees, this study examined the antecedents that affect the degree of disclosure of a gay identity at work and, for those who had not disclosed, the factors that influence their fears about full disclosure. Employees reported less fear and more disclosure when they worked in a group that was perceived as supportive and sharing their stigma. Perceptions of past experience with sexual orientation discrimination were related to increased fears but to greater disclosure. For those who had not fully disclosed their stigma, the fears associated with disclosure predicted job attitudes, psychological strain, work environment, and career outcomes. However, actual disclosure was unrelated to these variables. The utility of fear of disclosure for understanding processes underlying the disclosure of gay and other invisible stigmatized identities in the workplace is discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
997.
Meta-analysis was used to integrate research on the relations between parental socialization behavior and child and adolescent physical activity (PA) levels. Four major databases were examined: PubMED, ERIC, Web of Science, and PsychLit (1960 -2005). Thirty studies met the following inclusion criteria: (a) child age (2-18 years) and (b) statistical information permitting calculation of an effect size between parent socialization behavior and child PA. Mean age of participants across studies ranged from 2.54 to 15.5 years. The unweighted mean and median effect sizes (as indexed by r) were .17 and .13, respectively, indicating that a moderate positive relation exists between parental support and modeling behavior and child and adolescent PA levels. The moderating effect of type of parental socialization behavior, population characteristics, and methodological factors were investigated. Theoretical and methodological implications concern the inclusion of mediated models of parental influence and the use of longitudinal investigations in determining causal direction. From an applied viewpoint, these results are useful for the design of future, more effective childhood obesity prevention programs by suggesting child-age-appropriate parental influences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
The rising costs of new psychological tests, increased frequency of test revisions, and difficulty receiving authorization and reimbursement from managed care companies make it increasingly difficult for practitioners to provide the best standard of care to clients when conducting psychological and neuropsychological assessments. Practitioners, especially those in low-income and rural areas, may struggle with handling these practical realities while maintaining ethical standards in conducting psychological assessment. Suggestions for how to manage practical challenges faced by practitioners who provide psychological assessments, such as selecting tests when authorization or reimbursement by a third-party payer is restricted or denied, purchasing psychological tests on a budget, and providing assessments with a limited number of qualified staff are discussed. The authors also provide recommendations for the future prevention of these challenges through work with test developers, test publishing corporations, third-party payers, political action groups, and the psychology profession itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
999.
It has been more than four years since the last of my infrequent editorials in the International Journal of Stress Management (IJSM) and nearly a decade since my first (Carlson, 1998b). I am writing to you at this time first to inform you of a change in editorship, then to summarize a few high points of the past 10 years of IJSM as they relate to its management and future. My focus will be on matters dear to journal editors and useful to submitters and subscribers concerning submissions, content, and editorial activity, since such issues determine journal policy and direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Objective: To test hypothesized relations between hope and self-efficacy for rehabilitation to depression and functional ability reported by individuals receiving joint replacement surgery. Study Design: Community-dwelling older adults (N = 100) from an orthopaedic clinic were administered measures of hope, self-efficacy for rehabilitation, pain, depression, body mass index (BDI), and mental status 1 month prior to their joint replacement surgery. These measures were completed by 62 participants 6 weeks after surgery. Demographic, health information, and functional outcome measures were obtained by medical personnel pre- and postsurgery. Main Outcome Measures: Functional outcome measures (Harris Hip and Knee Society Scores) and depressive symptomatology. Results: Hope was significantly predictive of presurgery depression, but it was not predictive of depression or functional ability after surgery. Higher levels of self-efficacy were predictive of lower postsurgery depression scores. Conclusions: Results imply that social-cognitive constructs may have utility in the prediction of emotional adjustment before and after joint surgery, but they may have limited value in anticipating functional abilities following these surgeries. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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