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851.
Jason M. Newcomer Patti J. Clark Dixie K. Button Linda V. Weiland 《Journal of Gender Studies》2018,27(5):509-521
Certified aircraft mechanics represent the largest gender-based demographic disparity in aviation with a 49-to-1 male-to-female ratio. Recent research into women’s perspective on the aircraft mechanic career field revealed that a large majority of women felt unsure or negatively about their potential promotion opportunities and social acceptance. The purpose of this follow-on mixed-methods concurrent triangulation study was to explore the perspectives of men regarding the aforementioned topics to see if they differ from previously published research on women perceptions. A total of 587 men and 431 women completed an eight-question survey containing 5-point Likert-type and open-ended questions. The quantitative comparison consisted of the total 1018 responses, while only the survey responses from the 587 men were analysed for correlations and qualitative codes. Results indicated that there was a significant difference between the perceptions of men from those of the women regarding work environment safety and social acceptance. Additional correlation analysis revealed social acceptance to be a key variable when predicting career appropriateness, advancement opportunity and work environment safety. The 587 qualitative responses yielded results that differed from those of women, citing an assumption that women have the same advancement opportunities or be as socially accepted as men entering the field. 相似文献
852.
Using interview and survey data, we argue there are three types of places in the rural United States, and that their social and economic conditions help us understand emerging political trends, including the rural support for Donald Trump. More rural votes were cast for the Republican presidential candidate in 2016 than in other recent elections, yet shifts to Republican votes were greatest in places undergoing the most significant economic transitions. Work in rural communities has been a source of pride and cultural identity for people as well as places, but many feel the new economy is not working for them. 相似文献
853.
Atika Khurana Daniel Romer Laura M. Betancourt Hallam Hurt 《Journal of youth and adolescence》2018,47(9):1992-2005
Developmental imbalance models attribute the rise in risk-taking during adolescence to a universal imbalance between rising reward sensitivity and lagging cognitive control. This study tested predictions of an alternate Lifespan Wisdom Model that distinguishes between exploratory/adaptive (e.g., sensation seeking) and maladaptive (e.g., acting-without-thinking, delay discounting) risk-taking propensities and attributes the latter to a sub-set of youth with weak cognitive control. Latent trajectory modeling of six waves of data from 387 adolescents (52% females; spanning average ages of 11–18 years) revealed distinct sub-groups with heterogeneous trajectory patterns for acting-without-thinking and delay-discounting. Only those trajectory groups with weak cognitive control, characterized as “high-increasing” acting-without thinking and “high-stable” delay discounting were predictive of a maladaptive risk-taking outcome, namely substance use disorder. Sensation seeking demonstrated a universal peak, but high levels of sensation seeking were not associated with weakness in cognitive control and were unrelated to substance use disorder, controlling for impulsivity. The findings suggest that maladaptive risk-taking characterized by weak cognitive control over reward-driven impulses is a phenomenon limited to only a sub-set of youth. 相似文献
854.
Ian Scoones Marc Edelman Saturnino M. Borras Jr. Ruth Hall Wendy Wolford Ben White 《The Journal of peasant studies》2018,45(1):1-20
A new political moment is underway. Although there are significant differences in how this is constituted in different places, one manifestation of the new moment is the rise of distinct forms of authoritarian populism. In this opening paper of the JPS Forum series on ‘Authoritarian Populism and the Rural World’, we explore the relationship between these new forms of politics and rural areas around the world. We ask how rural transformations have contributed to deepening regressive national politics, and how rural areas shape and are shaped by these politics. We propose a global agenda for research, debate and action, which we call the Emancipatory Rural Politics Initiative (ERPI, www.iss.nl/erpi). This centres on understanding the contemporary conjuncture, working to confront authoritarian populism through the analysis of and support for alternatives. 相似文献
855.
A S Thomas 《Journal - Forensic Science Society》1989,29(4):243-248
The performance of the polymorphic marker systems group-specific component (GC), phosphoglucomutase-1 (PGM), alpha-2-HS-glycoprotein (A2HS), haptoglobin (Hp), and erythrocyte acid phosphatase (EAP) was evaluated on control bloodstains. The major factors considered were: sensitivity of the test system; stability of the marker; laboratory economics of each test; and distinguishing power (Dp) of the system. GC was considered to be the most suitable marker for routine screening because of its high stability and Dp, and the sensitivity of the immunoblotting detection method. PGM and A2HS were the next most valuable markers followed by Hp. EAP could only be considered useful when large amounts of relatively fresh bloodstain were available. 相似文献
856.
This report describes a collaborative study on typing group-specific component (GC), conducted between the Central Research and Support Establishment and the forensic science laboratories of England, Wales and Northern Ireland. A population study (n=114) was performed. Fifty blood donors were selected to provide a distribution, slightly biased from normal, in favour of the GC 1F-1F and GC 1F-1S phenotypes. A protocol was devised for preparing large bloodstains. The strongest GC bands were obtained from the edge of a stain after the blood had been treated with K+/EDTA. Each laboratory received a representative portion of the large bloodstains for GC typing. Five of the eight laboratories correctly grouped all the bloodstains. No errors directly attitributable to the system were recorded in over 800 tests, indicating that GC in bloodstains can be typed reliably using the combination of isoelectric focusing in ultrathin narrow pH interval gels followed by immunofixation and silver staining. 相似文献
857.
The most common examination in sexual offences is the identification of spermatozoa in aqueous extracts from swabs. Using Proteinase K with sodium dodecyl sulphate, it is possible to digest all the cellular material apart from the spermatozoa, resulting in a quick and effective method of their isolation. Spermatozoa were detected in 18 extracts using this treatment when the normal method had failed to reveal all but one of them. 相似文献
858.
A R Copeland 《Journal - Forensic Science Society》1989,29(3):185-189
The microscopic pathology of the liver in fatal cocaine intoxication was studied. Data from cases of cocaine intoxication during the years 1981-1986 were collected and analysed. Thirty cases with a negative past history for intravenous drug abuse, and in which the terminal drug testing revealed solely cocaine or its metabolites, were compared with a control group of nineteen people who had died in motor vehicle accidents, with a terminal negative blood alcohol, negative drug screen and no history of drug abuse. A comparison of liver histology was made along with gross anatomical liver weight. These findings are compared to other studies of hepatotoxicity in drug abuse. 相似文献
859.
A continuous model for interpreting the positions of bands in DNA locus-specific work. 总被引:1,自引:0,他引:1
A simple but rigorous approach is offered for evaluating the evidential value of single locus DNA autoradiographs. This approach does not use a binning technique and it does not treat alleles as discrete variables. Instead, the allele distribution is considered to be continuous. The variation between two comparable bands is assessed using previously determined experimental parameters. The Bayesian treatment leads to an expression of the "quality of a match". 相似文献
860.
A W Jones 《Journal - Forensic Science Society》1991,31(4):429-439
Blood ethanol profiles were determined in experiments with healthy volunteers after they had drunk beer. When 330 ml of light beer (1.8% w/v ethanol) was consumed in 5 min by four men and four women, the average peak blood-alcohol concentration (BAC) reached was 8 mg/100 ml (range 2-11). After nine men had drunk 660 ml of beer (3.0% w/v or 3.6% w/v ethanol) in 25 minutes on an empty stomach, the average peak BAC was 32 mg/100 ml (range 26-44) and 37 mg/100 ml (range 23-54) respectively. When the same two beers were consumed by another nine men together with a meal, the peak BAC was 24 mg/100 ml (range 20-29) and 28 mg/100 ml (range 20-39) respectively. The peak BAC occurred earlier when beer was ingested together with food; mean 32 min (range 30-50) compared with 41 min (range 30-70) with an empty stomach. The rate of disappearance of alcohol from blood (beta-slope) was 12 mg/100 ml/h in the fed state and 15 mg/100 ml/h when subjects were fasted. The apparent volume of distribution of ethanol (Vd) was 0.65 l/kg (SD 0.07) for the empty stomach condition but exceeded unity when beer was ingested together with food. It seems that part of the dose of alcohol when consumed with food never reaches the systemic circulation. 相似文献