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101.
I. Gilad 《国际生产研究杂志》2013,51(24):5415-5441
From a practical point of view, the cost effectiveness of ergonomic solutions is often questioned. Many times managers omit ergonomic solutions because of their high cost. This paper introduces a way to implement cost effective ergonomic solutions by coupling computer-aided design and predetermined motion time systems. This is done by generating a comparison between the operation times and body motions used in existing and safer work situations. We demonstrate using two case studies how solutions may impact operation times and stress, to which workers are subjected, which may be expressed in relaxation allowances required for resting and recovery. The ‘final product’ which may interest management the most, the ergonomic recommendations, is presented in easy to understand figures and numbers, including time to return on investment on relevant ergonomic solutions, which becomes possible when suggested improvements to work-situations are translated to time and cost. 相似文献
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103.
Shields Alexandra E.; Fortun Michael; Hammonds Evelynn M.; King Patricia A.; Lerman Caryn; Rapp Rayna; Sullivan Patrick F. 《Canadian Metallurgical Quarterly》2005,60(1):77
The use of racial variables in genetic studies has become a matter of intense public debate, with implications for research design and translation into practice. Using research on smoking as a springboard, the authors examine the history of racial categories, current research practices, and arguments for and against using race variables in genetic analyses. The authors argue that the sociopolitical constructs appropriate for monitoring health disparities are not appropriate for use in genetic studies investigating the etiology of complex diseases. More powerful methods for addressing population structure exist, and race variables are unacceptable as gross proxies for numerous social/environmental factors that disproportionately affect minority populations. The authors conclude with recommendations for genetic researchers and policymakers, aimed at facilitating better science and producing new knowledge useful for reducing health disparities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
3 从1 Gbit/s EPON升级至10 Gbit/s EPON 10 Gbit/s EPON从一开始就明确作为现有EPON的兼容升级方案,所选择的波长不会影响当前的EPON,因此可以在现有光纤链路上同时部署两种技术. 相似文献
105.
In this case study, wiki technology was applied to the development of an introductory academic textbook on information systems. While the development, production and distribution of traditional textbooks are influenced by commercial interests, the wikitextbook was developed collaboratively by faculty and by students, and was made available online free of charge. After about two years of activity, the wikitextbook accumulated 564 sub-chapters, co-authored by undergraduate and graduate students in more than 20 classes offered by seven academic departments across three Israeli universities. We discuss the potential of wikitextbooks as vehicles of empowerment to students, teachers, and the discipline. This type of collaborative online technology intimates an influence on the status-quo in academic education in favor of less empowered stakeholders. However, caution is advised in drawing premature conclusions from results reported here. The implementation of wikitextbook should be augmented by a careful study of cultural, societal, behavioral and pedagogic variables. 相似文献
106.
Particle tracking has become an increasingly useful tool in microfluidics and biophysics, allowing measurement of microrheology, local structure, and flow. We introduce a novel, automated approach to analyze single-particle trajectories with transient elements, based on image-processing approaches and physical analysis of probe motion. In many physical and active biological systems, such as living cells, probe particles experience thermally mediated Brownian motion combined with active transport processes that can lead to transient-trajectories of local diffusion and trapping, punctuated by segments of active transport. Analyzing such a trajectory as a single unit masks the intermittent nature of the motion. Moreover, directly applying the generalized Stokes–Einstein relation in out-of-equilibrium systems is incorrect and returns inaccurate rheological parameters. We present an automated image-processing-based method to identify and segment transient trap-escape trajectories, allowing quantitative analysis of each segment. We define and discuss effects of controlling parameters, such as particle size and camera frame rate. Our algorithm provides a general and automated method to segment and analyze transient elements in trajectories of single particles, which can be applied to many different experiments. Our image-based approach allows identification of trapping segments, unbiased by specific step sizes within those traps or the mechanism driving those steps. As an example, we successfully apply this method to experiments of laser tweezers trapped particles and show that trajectory segmentation allows us to calculate both trap and fluid parameters. We accurately identify a round trap, calculate the trap stiffness at 3.1?pN/μm, and find that significant local heating reduces fluid viscosity. 相似文献
107.
Chen Gilad; Gully Stanley M.; Whiteman Jon-Andrew; Kilcullen Robert N. 《Canadian Metallurgical Quarterly》2000,85(6):835
Several authors (e.g., J. T. Austin & H. J. Klein, 1996; R. Kanfer, 1990b, 1992) have urged researchers to examine comprehensive models of distal individual differences as predictors of proximal motivational processes and performance. Two field studies in an academic setting tested a model of relationships among trait-like individual differences (cognitive ability, general self-efficacy, and goal orientation), state-like individual differences (state anxiety, task-specific self-efficacy, and goals), and learning performance. Most hypothesized relationships among these constructs received support when tested on 2 samples, when examining different performance episodes, and when using different goal orientation and state-anxiety measures. In general, state-like individual differences were found to mediate the relationships between trait-like individual differences and learning performance. Implications of these results are discussed and suggestions for future research are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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109.
JW Fondon GM Mele RI Brezinschek D Cummings A Pande J Wren KM O'Brien KC Kupfer MH Wei M Lerman JD Minna HR Garner 《Canadian Metallurgical Quarterly》1998,95(13):7514-7519
A computational system for the prediction of polymorphic loci directly and efficiently from human genomic sequence was developed and verified. A suite of programs, collectively called POMPOUS (polymorphic marker prediction of ubiquitous simple sequences) detects tandem repeats ranging from dinucleotides up to 250 mers, scores them according to predicted level of polymorphism, and designs appropriate flanking primers for PCR amplification. This approach was validated on an approximately 750-kilobase region of human chromosome 3p21.3, involved in lung and breast carcinoma homozygous deletions. Target DNA from 36 paired B lymphoblastoid and lung cancer lines was amplified and allelotyped for 33 loci predicted by POMPOUS to be variable in repeat size. We found that among those 36 predominately Caucasian individuals 22 of the 33 (67%) predicted loci were polymorphic with an average heterozygosity of 0.42. Allele loss in this region was found in 27/36 (75%) of the tumor lines using these markers. POMPOUS provides the genetic researcher with an additional tool for the rapid and efficient identification of polymorphic markers, and through a World Wide Web site, investigators can use POMPOUS to identify polymorphic markers for their research. A catalog of 13,261 potential polymorphic markers and associated primer sets has been created from the analysis of 141,779,504 base pairs of human genomic sequence in GenBank. This data is available on our Web site (pompous.swmed.edu) and will be updated periodically as GenBank is expanded and algorithm accuracy is improved. 相似文献
110.
JS Brunet P Ghadirian TR Rebbeck C Lerman JE Garber PN Tonin J Abrahamson WD Foulkes M Daly J Wagner-Costalas A Godwin OI Olopade R Moslehi A Liede PA Futreal BL Weber GM Lenoir HT Lynch SA Narod 《Canadian Metallurgical Quarterly》1998,90(10):761-766
BACKGROUND: Smoking has carcinogenic effects, and possibly antiestrogenic effects as well, but it has not been found to be a risk factor for breast cancer in women in the general population. However, hereditary breast cancer is primarily a disease of premenopausal women, and interactions between genes and hormonal and environmental risk factors may be particularly important in this subgroup. METHODS: We conducted a matched case-control study of breast cancer among women who have been identified to be carriers of a deleterious mutation in either the BRCA1 or the BRCA2 gene. These women were assessed for genetic risk at one of several genetic counseling programs for cancer in North America. Information about lifetime smoking history was derived from a questionnaire routinely administered to women who were found to carry a mutation in either gene. Smoking histories of case subjects with breast cancer and age-matched healthy control subjects were compared. Odds ratios for developing breast cancer were determined for smokers versus nonsmokers by use of conditional logistic regression for matched sets after adjustment for other known risk factors. RESULTS: Subjects with BRCA1 or BRCA2 gene mutations and breast cancer were significantly more likely to have been nonsmokers than were subjects with mutations and without breast cancer (two-sided P = .007). In a multivariate analysis, subjects with BRCA1 or BRCA2 mutations who had smoked cigarettes for more than 4 pack-years (i.e., number of packs per day multiplied by the number of years of smoking) were found to have a lower breast cancer risk (odds ratio = 0.46, 95% confidence interval = 0.27-0.80; two-sided P = .006) than subjects with mutations who never smoked. CONCLUSIONS: This study raises the possibility that smoking reduces the risk of breast cancer in carriers of BRCA1 or BRCA2 gene mutations. 相似文献