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961.
Light,timing of biological rhythms,and chronodisruption in man 总被引:3,自引:2,他引:3
This paper reviews abundant evidence suggesting that causes and course of aging and cancers can be considered as being both light- and rhythm-related. We define chronodisruption as a relevant disturbance of orderly biological rhythms over days and seasons and years in man. Light is the primary external mediator and melatonin a primary internal intermediary of such disturbances, which can result in earlier deaths via premature aging and cancers. We conclude that experimental and epidemiological research can provide further insights into common denominators of these chronic processes and may offer novel and uniform targets for prevention. 相似文献
962.
Ronald L. Thomas MD 《黑龙江环境通报》1992,12(11):919-923
Cystic hygromas have historically been associated with a grim prognosis when discovered during prenatal sonographic study of the fetus. This same grim prognosis is not observed by the paediatric surgeon who evaluates the neonate or paediatric patient. We present a fetal patient with a massive anterior cystic hygroma discovered in the third trimester prior to 30 weeks. This case and a review of the literature suggest tailoring the prognosis by category when counselling patients: (1) first trimester, normal karyotype-good; (2) first trimester, abnormal karyotype-poor; (3) second trimester and early third-poor to guarded; and (4) mid to late third trimester-good. 相似文献
963.
Brian S. Caruso Brian Newman Thomas Econopouly 《Journal of the American Water Resources Association》2019,55(3):622-640
We performed two‐dimensional (2D) hydrodynamic modeling to aid recovery of the endangered razorback sucker (Xyrauchen texanus) by reconnecting the Green River with its historic bottomland floodplain wetlands at Ouray National Wildlife Refuge, Utah. Reconnection allows spring flood flows to overtop the river levee every two to three years, and passively transport razorback sucker larvae to the wetlands to grow in critical habitat. This study includes (1) river hydrologic analysis, (2) simulation of a levee breach/weir, overtopping of river flood flows, and 2D flow through the wetlands using Hydrologic Engineering Center River Analysis System 2D, and (3) modeling flow and restoration scenarios. Indicators of hydrologic alteration were used to evaluate river flow metrics, in particular flood magnitudes, frequency, and duration. Results showed a target spring flow of 16,000 cfs (453 m3/s) and a levee breach elevation of 4,663 ft (1,421 m) amsl would result in a median flow >6,000 acre‐feet (7.4 million m3) over five days into the wetlands, which is adequate for razorback sucker larvae transport and rearing. Modeling of flow/restoration scenarios showed using gated water control structures and passive low‐water crossings between wetland units can provide adequate control of flow movement into and storage in multiple units. Levee breaching can be a relatively simple, cost‐effective method to reconnect rivers and historic floodplains, and hydrodynamic modeling is an important tool for analyzing and designing wetland reconnection. 相似文献
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Two important gaps remain to be filled in the idiosyncratic deals (i‐deals) literature. First, it is unclear which employees are predisposed to seek and receive i‐deals. Second, it is unclear how employees' perceptions of whether their coworkers are receiving i‐deals affect their own i‐deal experiences. This study proposed a theoretical model suggesting that (a) three key motivational goals identified in human development research, that is, achievement, status, and communion striving, predispose employees to seek and receive i‐deals; (b) employees' perceptions of whether their coworkers are receiving i‐deals moderate these relationships; and (c) employees' i‐deals are related to their job behavior. Data collected from more than 400 working adults in Italy showed that employees' motivational goals (particularly achievement and status striving) were positively related to the levels of i‐deals they received, and that these i‐deals were in turn positively related to supervisors' assessments of their in‐role job performance, voice behavior, and interpersonal citizenship behavior. High perceptions of the extent to which coworkers received i‐deals further strengthened the relationship between status striving and employees' perceptions of their own i‐deals, highlighting a trait‐situation interactionist perspective on employees' i‐deal experiences. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
969.
For much of the world''s population, food is the major source of exposure to arsenic. Exposure to this non-essential metalloid at relatively low levels may be linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important in assessing risk and developing strategies that protect public health. Although most emphasis has been placed on inorganic arsenic as human carcinogen and toxicant, an array of arsenic-containing species are found in plants and animals used as foods. Here, we 2evaluate the contribution of complex organic arsenicals (arsenosugars, arsenolipids, and trimethylarsonium compounds) that are found in foods and consider their origins, metabolism, and potential toxicity. Commonalities in the metabolism of arsenosugars and arsenolipids lead to the production of di-methylated arsenicals which are known to exert many toxic effects. Evaluating foods as sources of exposure to these complex organic arsenicals and understanding the formation of reactive metabolites may be critical in assessing their contribution to aggregate exposure to arsenic. 相似文献
970.
Thomas?WinklerEmail author Wilfried?Winiwarter 《Mitigation and Adaptation Strategies for Global Change》2016,21(8):1181-1196
In the present paper, national and externally organized projections of greenhouse gas emissions for Austria were compared to gain insight on the underlying scenario data assumptions. National greenhouse gas emission trends extend until 2030, an assessment of European Union (EU) countries to 2050. In addition, data for 2000–2100 was extracted from the global emission database described by the Representative Concentration Pathways (RCP). By identifying trends in these projections, it was possible to produce (a) a long-term assessment of national scenarios until 2100, (b) an assessment of the ambition level toward national climate strategies, and (c) a standardized method to compare trends across countries. By extracting RCP data, Austrian’s methane, nitrous oxide, and carbon dioxide emissions up to 2100 could be projected for all sources as well as specific sectors. With respect to the RCP scenario emission data, national projections did not seem to employ the mitigation potentials available for the most stringent RCP scenario, RCP2.6. Comparing projections that supported the EU Climate Strategy 2030 with national projections revealed similar trends. Because RCP2.6 is the only scenario consistent with a 2 °C global warming target, and it is much more ambitious than any of the national or European projections, further measures will be required if Austria is to adequately contribute to this widely accepted policy goal. 相似文献