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241.
In response to water quality standard violations linked to excessive organic matter (OM) and a lack of sampling data informing the Total Maximum Daily Load (TMDL), an organic matter budget was created to quantify and identify sources of OM in the lower Jordan River (Salt Lake City, UT). By sampling dissolved, fine and coarse particulate OM, as well as measuring ecosystem metabolism at seven different sites, the researchers aimed to identify the origin of excess OM, and understand pathways by which different size classes of the OM pool are generated. The dissolved fraction (DOM; 94 %) was found to be the dominant form of OM transported within the river with fine particulate organic matter (FPOM; 6 %) the second most abundant, and coarse particulate organic matter (CPOM; 1 %) transport relatively insignificant in the overall OM budget. Primary production exceeded respiratory losses in the upper river, and this, along with OM inputs from two tributaries (where water reclamation facilities discharge into the river) delivered excess OM to the impaired lower reaches. Increasing stream metabolism index (SMI) with distance downstream (>1 in the lower river) further demonstrated that transport of excessive organic matter into the lower river was from upstream sources and not due to lateral inputs. This simple approach to characterizing the organic matter budget as it relates to water quality in the Jordan River was effective and could serve as a model for future studies attempting to quantify and identify sources of OM in urban ecosystems. 相似文献
242.
Landon E. Hancock 《National Identities》2016,18(4):409-423
I propose a lens model for understanding how core identities (ethnic, sectarian, racial or national) are affected by past interactions and narratives increasing the chances of the outbreak of violent conflict. The model can be used to show how core identities are polarized during conflict escalation and how they might de-polarize during periods of de-escalation and conflict resolution, leading to potential transformation of core identities in post-conflict situations. Northern Ireland will be used to illustrate the Integrated Relational Identity Structure model, showing how conflicting identities have changed, or not, as a result of history, the conflict and the peace process. 相似文献
243.
Damian E. M. Milton 《Disability & Society》2017,32(10):1671-1676
With the passing of Robert M. Pirsig, I felt that it was an appropriate time to write a tribute to his work and the influence it has had on my own theorising in regard to autistic ways of being. This reflection utilises the concept of an ‘aut-ethnography’ to examine passages that I had highlighted word by word when I first read Pirsig’s book: Zen and the Art of Motorcycle Maintenance. These fragments contain links to a number of theoretical ‘lines of flight’ within my own work and that of others, from his concepts of dynamic ‘quality’ to his discussion on the tension between scientific method and lived experience. 相似文献
244.
Philip Looper David George Eric J. Johnson Susan E. Conway 《Journal of American college health : J of ACH》2017,65(7):513-517
Objective: To examine the perceptions among faculty and health professional students regarding mandatory vaccination policies on a health sciences campus. Participants: A total of 296 faculty and 244 students completed surveys during Fall 2015. Methods: The online survey administered to individuals who received the influenza vaccine during the fall 2015 influenza vaccination clinic season included five items evaluating perceptions of employer mandatory vaccination requirements. Results: Chi-square analysis indicated that although faculty and students agree mandatory vaccinations in a health care environment are appropriate, faculty are more likely than students to get vaccinated in the absence of a mandate. Additionally, a small fraction of faculty would consider employment elsewhere when facing this mandate. Conclusions: Overall, faculty and students had favorable perceptions about mandatory influenza vaccine policies. Since students were less likely to be vaccinated in the absence of a mandate, education of students should be improved to support the importance of vaccinations in a health care environment. 相似文献
245.
Using In Vitro High‐Throughput Screening Data for Predicting Benzo[k]Fluoranthene Human Health Hazards
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Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods. 相似文献
246.
E. J. Vanderperre 《统计学通讯:理论与方法》2017,46(16):7872-7886
We analyze the survival time of a general duplex system sustained by a cold standby unit subjected to a priority rule. The analysis is based on advanced complex function theory (sectionally holomorphic functions). As an example, we consider Weibull–Gnedenko and Erlang distributions for failure and repair. Several graphs are displaying the survival function. 相似文献
247.
Aksam Yassin Joanne E. Nettleship Raidh A. Talib Yousef Almehmadi Gheorge Doros 《The aging male》2016,19(1):64-69
Whether testosterone replacement therapy (TRT) is a lifelong treatment for men with hypogonadism remains unknown. We investigated long-term TRT and TRT withdrawal on obesity and prostate-related parameters. Two hundred and sixty-two hypogonadal patients (mean age 59.5) received testosterone undecanoate in 12-week intervals for a maximum of 11 years. One hundred and forty-seven men had TRT interrupted for a mean of 16.9 months and resumed thereafter (Group A). The remaining 115 patients were treated continuously (Group B). Prostate volume, prostate-specific antigen (PSA), residual voiding volume, bladder wall thickness, C-reactive protein (CRP), aging male symptoms (AMS), International Index of erectile function – erectile function (IIEF-EF) and International Prostate Symptoms Scores (IPSS) were measured over the study period with anthropometric parameters of obesity, including weight, body mass index (BMI) and waist circumference. Prior to interruption, TRT resulted in improvements in residual voiding volume, bladder wall thickness, CRP, AMS, IIEF-EF, IPSS and obesity parameters while PSA and prostate volume increased. TRT interruption reduced total testosterone to hypogonadal levels in Group A and resulted in worsening of obesity parameters, AMS, IPSS, residual voiding volume and bladder wall thickness, IIEF-EF and PSA while CRP and prostate volume were unchanged until treatment resumed whereby these effects were reversed. TRT interruption results in worsening of symptoms. Hypogonadism may require lifelong TRT. 相似文献
248.
David E. Bloom Mathew J. McKenna Klaus Prettner 《International social security review》2019,72(3):43-78
Globally, an estimated 734 million jobs will be required between 2010 and 2030 to accommodate recent and ongoing demographic shifts, account for plausible changes in labour force participation rates, and achieve target unemployment rates of at or below 4 per cent for adults and at or below 8 per cent for youth. The facts that most new jobs will be required in countries where “decent” jobs are less prevalent and workers in many occupations are increasingly subject to risks of automation further compound the challenge of job creation, which is already quite sizable in historical perspective. Failure to create the jobs that are needed through 2030 would put currently operative social security systems under pressure and undermine efforts to guarantee the national social protection floors enshrined in the Sustainable Development Goals (SDGs). 相似文献
249.
This study examined whether being in a romantic relationship is associated with undergraduates’ alcohol use and negative consequences of drinking. Alcohol use was operationalized to include amount and frequency of drinking, binge drinking, and drunkenness. Negative consequences included: having a hangover, missing a class, getting behind in school work, doing something that was later regretted, forgetting where the student was or what they did, having unplanned sex, and getting hurt or injured. Data came from an online survey distributed to Midwestern undergraduate students (N = 572), with analyses conducted separately for men and women. Results indicated that being in a committed relationship generally served as a protective factor against drunkenness, but did not reduce frequency of drinking or binge drinking. Whereas romantically committed men were only less likely to report doing something that was later regretted, women in romantic relationships were less likely to experience all negative consequences of drinking considered here. 相似文献
250.