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101.
Three studies investigated how inclusion versus exclusion strategies differentially lead to stereotypic decisions. In inclusion strategies, suitable targets are selected from a list of candidates, whereas in exclusion strategies, unsuitable candidates are eliminated. Across 2 separate target domains (Study 1: male and female politicians; Studies 2 and 3: African American and European American basketball players), exclusion strategies, as compared with inclusion strategies, elicited higher levels of both sensitivity stereotyping (i.e., greater difficulty distinguishing among members of stereotyped groups) and criterion stereotyping (i.e., setting different decision thresholds for judging members of different groups; see M. R. Banaji & A. G. Greenwald, 1995). Thus, the strategy used during decision making can influence the final decision via 2 theoretically distinct stereotyping mechanisms. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
102.
Posttraumatic stress (PTS) symptoms have been reported in mothers and fathers of childhood cancer survivors; however, little is known about patterns of PTS in these families. Cluster analysis was applied to the Posttraumatic Stress Disorder (PTSD) Reaction Index scores of 98 couples parenting adolescent childhood cancer survivors to describe patterns of PTS in families, yielding the following 5 clusters: Minimal PTS, Mothers Elevated, Disengaged, Fathers Elevated, and Elevated PTS. The clusters were validated using data from a structured psychiatric interview, an additional self-report measure of PTS, and an index of family functioning. These clinically meaningful patterns reveal that a majority of families had at least one parent with moderate to severe PTS, which supports development of family-based interventions for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
In the world of air regulations, the year 2016 will be remembered not for any major action by the Environmental Protection Agency (EPA) in developing, revising, or defending its rules, but for the result of the November 8 presidential election that took most of the United States, if not the world, by surprise. Donald Trump's election and the transition to a Republican administration will undoubtedly be the primary influence (and major question mark) in the air quality regulation landscape in 2017. As Trump prepares to take office, speculation is rampant about whether the promises he made on the campaign trail will translate into action. Chief among those promises was a vow to eliminate or roll back efforts aimed at regulating climate change, including the repeal of the EPA's Clean Power Plan (CPP) and withdrawal from the Paris climate change accord.  相似文献   
104.
Aldehyde dehydrogenase 3A1 (ALDH3A1) plays an important role in many cellular oxidative processes, including cancer chemoresistance, by metabolizing activated forms of oxazaphosphorine drugs such as cyclophosphamide (CP) and its analogues, such as mafosfamide (MF), ifosfamide (IFM), and 4‐hydroperoxycyclophosphamide (4‐HPCP). Compounds that can selectively target ALDH3A1 could permit delineation of its roles in these processes and could restore chemosensitivity in cancer cells that express this isoenzyme. Here we report the detailed kinetic and structural characterization of an ALDH3A1‐selective inhibitor, CB29, previously identified in a high‐throughput screen. Kinetic and crystallographic studies demonstrate that CB29 binds within the aldehyde substrate‐binding site of ALDH3A1. Cellular proliferation of ALDH3A1‐expressing lung adenocarcinoma (A549) and glioblastoma (SF767) cell lines, as well as ALDH3A1 non‐expressing lung fibroblast (CCD‐13Lu) cells, is unaffected by treatment with CB29 and its analogues alone. However, sensitivity toward the anti‐proliferative effects of mafosfamide is enhanced by treatment with CB29 and its analogue in the tumor cells. In contrast, the sensitivity of CCD‐13Lu cells toward mafosfamide was unaffected by the addition of these same compounds. CB29 is chemically distinct from the previously reported small‐molecule inhibitors of ALDH isoenzymes and does not inhibit ALDH1A1, ALDH1A2, ALDH1A3, ALDH1B1, or ALDH2 isoenzymes at concentrations up to 250 μM . Thus, CB29 is a novel small molecule inhibitor of ALDH3A1, which might be useful as a chemical tool to delineate the role of ALDH3A1 in numerous metabolic pathways, including sensitizing ALDH3A1‐positive cancer cells to oxazaphosphorines.  相似文献   
105.
106.
Emitted to the atmosphere through fire and fossil fuel combustion, refractory black carbon nanoparticles (rBC) impact human health, climate, and the carbon cycle. Eventually these particles enter aquatic environments, where they may affect the fate of other pollutants. While ubiquitous, the particles are still poorly characterized in freshwater systems. Here we present the results of a study determining rBC in waters of the Lake Tahoe watershed in the western United States from 2007 to 2009. The study period spanned a large fire within the Tahoe basin, seasonal snowmelt, and a number of storm events, which resulted in pulses of urban runoff into the lake with rBC concentrations up to 4 orders of magnitude higher than midlake concentrations. The results show that rBC pulses from both the fire and urban runoff were rapidly attenuated suggesting unexpected aggregation or degradation of the particles. We find that those processes prevent rBC concentrations from building up in the clear and oligotrophic Lake Tahoe. This rapid removal of rBC soon after entry into the lake has implications for the transport of rBC in the global aquatic environment and the flux of rBC from continents to the global ocean.  相似文献   
107.
The relative contribution of regional contamination versus dietary differences to geographic variation in polar bear (Ursus maritimus) contaminant levels is unknown. Dietary variation between Alaska, Canada, East Greenland, and Svalbard subpopulations was assessed by muscle nitrogen and carbon stable isotope (δ(15)N, δ(13)C) and adipose fatty acid (FA) signatures relative to their main prey (ringed seals). Western and southern Hudson Bay signatures were characterized by depleted δ(15)N and δ(13)C, lower proportions of C(20) and C(22) monounsaturated FAs and higher proportions of C(18) and longer chain polyunsaturated FAs. East Greenland and Svalbard signatures were reversed relative to Hudson Bay. Alaskan and Canadian Arctic signatures were intermediate. Between-subpopulation dietary differences predominated over interannual, seasonal, sex, or age variation. Among various brominated and chlorinated contaminants, diet signatures significantly explained variation in adipose levels of polybrominated diphenyl ether (PBDE) flame retardants (14-15%) and legacy PCBs (18-21%). However, dietary influence was contaminant class-specific, since only low or nonsignificant proportions of variation in organochlorine pesticide (e.g., chlordane) levels were explained by diet. Hudson Bay diet signatures were associated with lower PCB and PBDE levels, whereas East Greenland and Svalbard signatures were associated with higher levels. Understanding diet/food web factors is important to accurately interpret contaminant trends, particularly in a changing Arctic.  相似文献   
108.
This study sought to determine the frequency with which food workers said they had worked while experiencing vomiting or diarrhea, and to identify restaurant and worker characteristics associated with this behavior. We conducted interviews with food workers (n=491) and their managers (n=387) in the nine states that participate in the Centers for Disease Control and Prevention's Environmental Health Specialists Network. Restaurant and worker characteristics associated with repeatedly working while experiencing vomiting or diarrhea were analyzed via multivariable regression. Fifty-eight (11.9%) workers said they had worked while suffering vomiting or diarrhea on two or more shifts in the previous year. Factors associated with workers having worked while experiencing vomiting or diarrhea were (i) high volume of meals served, (ii) lack of policies requiring workers to report illness to managers, (iii) lack of on-call workers, (iv) lack of manager experience, and (v) workers of the male gender. Our findings suggest that policies that encourage workers to tell managers when they are ill and that help mitigate pressures to work while ill could reduce the number of food workers who work while experiencing vomiting or diarrhea.  相似文献   
109.
We have measured the Fourier transform spectrum of natural OCS from 3700 to 4800 cm-1 with a near Doppler resolution and a line-position accuracy between 4 and 8 x 10(-5) cm-1. For the normal isotopic species, 37 vibrational transitions have been analyzed for both frequencies and intensities. We also report 15 bands of OC34S, eight bands of O13CS, nine bands of OC33S, and two bands of 18OCS. Important effective Herman-Wallis terms are explained on the basis of eigenvectors. A comparison of different line-pointing programs is also presented. Copyright 1998 Academic Press.  相似文献   
110.
Vernonia galamensis oil, containing naturally epoxidized triglycerides, was reacted withn-butylamine,n-pentylamine andn-hexylamine to afford high yields of epoxidized secondary amides. Three reaction conditions were investigated: (i) reflux with amines as solvents, (ii) reflux with hexane as the solvent and (iii) room temperature with the amines as solvents. Reactions with amines as refluxing solvents were completed in 1–5 h, while those with hexane went to completion within 2 to 5 d. Room temperature reactions were onlyca. 80% complete after several days. Reactivity was increased with higher amine homologs at both reflux and room temperature reaction conditions. Isolated yields of epoxy-containing amides were about 80% with purity exceeding 96% in all cases. Spectroscopic characterization of the previously unreported alkyl-vernolamides is provided.  相似文献   
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