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排序方式: 共有706条查询结果,搜索用时 15 毫秒
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63.
K V Horoshenkov Y A Yin A Schellart R M Ashley J R Blanksby 《Water science and technology》2004,50(11):97-104
The acoustic attenuation, relative sound pressure levels and the equivalent Nikuradse wall roughness under variable flow conditions in a 600 mm concrete sewer pipe are experimentally investigated. The values of the acoustic attenuation are obtained in the case of airborne sound propagation in the dry pipe. A range of values of the equivalent wall roughness is artificially generated by deploying a periodical array of engineering bricks. A novel method of rapid evaluation of the acoustic attenuation is proposed. The method relies upon sound reflections from the adjacent manholes. The results demonstrate that the acoustic attenuation depends strongly on the value of the equivalent wall roughness. This work can pave the way to the efficient methodology for the in-situ, physical evaluation of the equivalent hydraulic roughness of new and existing sewer networks. 相似文献
64.
Discovery of Quinoline‐Derived Trifluoromethyl Alcohols,Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model
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Prof. Dr. Vinoth Sittaramane Jihan Padgett Philip Salter Ashley Williams Shauntelle Luke Rebecca McCall Prof. Dr. Jonathan F. Arambula Vincent B. Graves Mark Blocker David Van Leuven Keturah Bowe Julia Heimberger Hannah C. Cade Supriya Immaneni Prof. Dr. Abid Shaikh 《ChemMedChem》2015,10(11):1802-1807
In this study the rational design, synthesis, and anticancer activity of quinoline‐derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp3‐C?H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4‐trifluoro‐3‐hydroxy‐3‐(quinolin‐2‐ylmethyl)butanoate ( 1 ), 2‐benzyl‐1,1,1‐trifluoro‐3‐(quinolin‐2‐yl)propan‐2‐ol ( 2 ), and trifluoro‐3‐(isoquinolin‐1‐yl)‐2‐(thiophen‐2‐yl)propan‐2‐ol ( 3 ). Compounds 2 and 3 were found to be more toxic than compound 1 ; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2 , with an LC50 value of 14.14 μm , has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents. 相似文献
65.
S. Dorr Brian Ashley Moerke Michael Bur Chuck Bassett Tony Aderman Dan Traynor Russell D. Singleton Peter H. Butchko Jimmy D. Taylor II 《Journal of Great Lakes research》2010
Diverse management techniques have been used to mitigate conflicts between humans and double-crested cormorants (Phalacrocorax auritus) including harassment methods supplemented by lethal take. In this study we evaluated impacts of programs to harass spring migrating cormorants on the walleye (Sander vitreus) fishery in Brevoort Lake and the yellow perch (Perca flavescens) and walleye fisheries at Drummond Island. Cormorant foraging declined significantly (p < 0.05) at both locations subsequent to initiation of harassment programs. Overall harassment deterred 90% of cormorant foraging attempts while taking less than 6% lethally on average at each site. Yellow perch were a predominate prey item in number and biomass at both locations. Walleye made up a small proportion of the diet at both locations. However, both walleye and yellow perch abundance increased significantly (p < 0.05) at Drummond Island. Walleye abundance at age 3 increased to record levels in 2008 following 3 years of cormorant management at Brevoort Lake. The estimated cormorant consumption of age-1 walleye in the absence of management at Brevoort Lake during 2005 would account for 55% of the record 2006 age-1 walleye population. These results support the hypothesis that cormorant predation on spawning aggregations of sportfish was a significant mortality factor and cormorant management reduced sportfish mortality and increased abundance at both locations. Continuation of harassment programs and fishery assessments will determine whether improvement of targeted sport fisheries through control of spring migrating cormorants is sustainable. 相似文献
66.
Miles AM Singer PC Ashley DL Lynberg MC Mendola P Langlois PH Nuckols JR 《Environmental science & technology》2002,36(8):1692-1698
Trihalomethane (THM) concentrations in blood and tap water were measured for 50 women living in two locations with different bromide concentrations and disinfectant types. Blood samples were taken from each woman early in the morning prior to any major water-use activity and again immediately after showering. Each residence was sampled for THMs in tap water prior to the woman's shower. Cobb County, GA, tap water exhibited high THM concentrations composed primarily of chloroform. Corpus Christi, TX, tap water exhibited lower THM concentrations with significant proportions of brominated THMs. THMs in tap water and blood were compared using mole fraction speciation, extent of bromine incorporation, and correlation analysis. Results indicated that THMs in the blood rose significantly as a result of showering, that showering shifted the THM distribution in the blood toward that found in the corresponding tap water, and that THMs measured in the blood of women living in the two locations reflected species and concentration differences in their respective tap waters. In general, blood concentrations were not significantly correlated with tap water concentrations. This finding suggests that other factors, in addition to tap water concentrations, may be important in determining THM concentrations in the blood. 相似文献
67.
In 2010 the U.S.A. National Science Foundation (NSF) started an initiative in Science, Engineering and Education for Sustainability (SEES) that is expected to continue through 2019 (according to the FY 2014 budget request). The overall mission of SEES is to advance science, engineering, and education to inform the societal actions needed for environmental and economic sustainability and sustainable human well-being. Along the way and at the conclusion of this initiative, many of the successful activities will be integrated into core NSF programs so they may continue to have impact beyond the lifetime of SEES. Predominantly, SEES has an interdisciplinary system focus, an emphasis on education and workforce development, and a motivation and plan for forming new partnerships and strengthening existing ones. Ceramics are key material components to many system solutions, particularly in the energy sector where structure and composition coupled with electrical and mechanical properties are important. As well, many areas critical to materials sustainability are of interest to ceramists, e.g., improving properties (e.g., durability), expanding the range of operational temperatures, and using safer elements that are abundant. In this paper, the NSF opportunities for funding, relevant topics of research, and examples of grants are described in more detail. 相似文献
68.
Evidence for fumonisin inhibition of ceramide synthase in humans consuming maize‐based foods and living in high exposure communities in Guatemala
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69.
The electronic properties of two-dimensional (2D) materials, like graphene, are of considerable fundamental interest. This paper describes how physically adsorbed films probe these properties. The cases of an ideal 2D free electron gas and graphene are examined, with explicit results found for an adsorbed He film. In the free electron case, the scattering is proportional to the 2D structure factor of the film. Results are presented for He on graphene and the free electron gas in both the low coverage and fully commensurate limits. 相似文献
70.
Madon Stephanie; Guyll Max; Buller Ashley A.; Scherr Kyle C.; Willard Jennifer; Spoth Richard 《Canadian Metallurgical Quarterly》2008,95(2):369
This research examined whether self-fulfilling prophecy effects are mediated by self-verification, informational conformity, and modeling processes. The authors examined these mediational processes across multiple time frames with longitudinal data obtained from two samples of mother-child dyads (N? = 486; N? = 287), with children's alcohol use as the outcome variable. The results provided consistent support for the mediational process of self-verification. In both samples and across several years of adolescence, there was a significant indirect effect of mothers' beliefs on children's alcohol use through children's self-assessed likelihood of drinking alcohol in the future. Comparatively less support was found for informational conformity and modeling processes as mediators of mothers' self-fulfilling effects. The potential for self-fulfilling prophecies to produce long-lasting changes in targets' behavior via self-verification processes are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献