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21.
In 4 studies, the authors examined whether making outcome expectancies distinct resulted in their use as comparison standards and, consequently, in contrastive dispositional inferences for a target's behaviors. The expectancies examined were based on either chronic future-event expectancies (Study 1) or temporary, manipulated expectancy standards (Studies 2–4). Analyses revealed that when contextual expectancies were distinct or separable from target information, participants' dispositional judgments were contrasted from them under cognitive load and overcorrected (assimilated to them) under no load. These effects were mediated by participants' behavior categorizations. Evidence suggestive of a proceduralized form of correction for task difficulty and an effortful awareness-based correction for the effects of expectancies also were found. Results are examined in light of recent models of the dispositional inference process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Nitrates fluxes in the Grand Morin basin (1200 km(2)), that is subjected to intense agricultural pressure, are considered using in-stream observations (around 250 sampling days over 5 years) and physically based simulations using the CAWAQS model (CAtchment WAter Quality Simulator). In-stream nitrate concentration averaged 6 mg N L(-1), increasing by approximately 0.2 mg N L(-1) yr(-1) around this value (period 1991-1996). Our results show that, over the period of 1991-1996, the differences between in-stream observed nitrate concentrations and simulated nitrate concentrations result from nitrate losses at the basin scale. These losses are due to denitrification by transfer through wetlands, alluvial plains, the hyporheic zone, and by benthic processes in rivers. A mean annual mass balance at the basin scale indicates that 40% of the infiltration flux (3360 kg N km(-2) yr(-1)) is removed from the system via the river network, 40% is stored in aquifers and 20% is lost by denitrification (period 1991-1996). 相似文献
23.
Power IM Wilson SA Small DP Dipple GM Wan W Southam G 《Environmental science & technology》2011,45(20):9061-9068
Ultramafic mine tailings from the Diavik Diamond Mine, Canada and the Mount Keith Nickel Mine, Western Australia are valuable feedstocks for sequestering CO? via mineral carbonation. In microcosm experiments, tailings were leached using various dilute acids to produce subsaline solutions at circumneutral pH that were inoculated with a phototrophic consortium that is able to induce carbonate precipitation. Geochemical modeling of the experimental solutions indicates that up to 2.5% and 16.7% of the annual emissions for Diavik and Mount Keith mines, respectively, could be sequestered as carbonate minerals and phototrophic biomass. CO? sequestration rates are mainly limited by cation availability and the uptake of CO?. Abundant carbonate mineral precipitation occurred when heterotrophic oxidation of acetate acted as an alternative pathway for CO? delivery. These experiments highlight the importance of heterotrophy in producing sufficient DIC concentrations while phototrophy causes alkalinization of waters and produces biomass (fatty acids = 7.6 wt.%), a potential feedstock for biofuel production. Tailings storage facilities could be redesigned to promote CO? sequestration by directing leachate waters from tailings piles into specially designed ponds where carbonate precipitation would be mediated by both chemical and biological processes, thereby storing carbon in stable carbonate minerals and potentially valuable biomass. 相似文献
24.
Comparison of PCR and quantitative real-time PCR methods for the characterization of ruminant and cattle fecal pollution sources 总被引:1,自引:0,他引:1
Meredith R. Raith Catherine A. Kelty John F. Griffith Alexander Schriewer Stefan Wuertz Sophie Mieszkin Michele Gourmelon Georg H. Reischer Andreas H. Farnleitner Jared S. Ervin Patricia A. Holden Darcy L. Ebentier Jennifer A. Jay Dan Wang Alexandria B. Boehm Tiong Gim Aw Joan B. Rose E. Balleste W.G. Meijer Mano Sivaganesan Orin C. Shanks 《Water research》2013
The State of California has mandated the preparation of a guidance document on the application of fecal source identification methods for recreational water quality management. California contains the fifth highest population of cattle in the United States, making the inclusion of cow-associated methods a logical choice. Because the performance of these methods has been shown to change based on geography and/or local animal feeding practices, laboratory comparisons are needed to determine which assays are best suited for implementation. We describe the performance characterization of two end-point PCR assays (CF128 and CF193) and five real-time quantitative PCR (qPCR) assays (Rum2Bac, BacR, BacCow, CowM2, and CowM3) reported to be associated with either ruminant or cattle feces. Each assay was tested against a blinded set of 38 reference challenge filters (19 duplicate samples) containing fecal pollution from 12 different sources suspected to impact water quality. The abundance of each host-associated genetic marker was measured for qPCR-based assays in both target and non-target animals and compared to quantities of total DNA mass, wet mass of fecal material, as well as Bacteroidales, and enterococci determined by 16S rRNA qPCR and culture-based approaches (enterococci only). Ruminant- and cow-associated genetic markers were detected in all filters containing a cattle fecal source. However, some assays cross-reacted with non-target pollution sources. A large amount of variability was evident across laboratories when protocols were not fixed suggesting that protocol standardization will be necessary for widespread implementation. Finally, performance metrics indicate that the cattle-associated CowM2 qPCR method combined with either the BacR or Rum2Bac ruminant-associated methods are most suitable for implementation. 相似文献
25.
This paper presents a simple and general modeling primitive, called a block, based on a generalized cuboid shape. Blocks are laid out and connected together to constitute the base shape of complex objects, from which is extracted a control mesh that can contain both smooth and sharp edges. The volumetric nature of the blocks allows for easy topology specification, as well as CSG operations between blocks. The surface parameterization inherited from the block faces provides support for texturing and displacement functions to apply surface details. A?variety of examples illustrate the generality of our blocks in both interactive and procedural modeling contexts. 相似文献
26.
27.
Orsino Oliveira Filho Jose Antonio Cardoso Darcy Ramalho de Mello Rogerio Magalhges de Azevedo Sylvia G Carvalho 《高电压技术》2011,37(11):2772-2779
Studies based on AC high voltage tests have been done at Cepel to investigate the performance of 800 kV bushar insulators under heavy wetting conditions. Insulators were tested which are now used on si... 相似文献
28.
Reviews the book, Cross-cultural research methods in psychology edited by David Matsumoto and Fons J. R. Van de Vijver (see record 2010-22491-000). The purpose of this book is to further the potential of cross-cultural psychology by helping researchers to understand the unique difficulties inherent in the field and the current methodologies used to advance quality research. Matsumoto and van de Vijver have compiled a comprehensive yet simply organized volume that speaks to the theoretical and analytic issues met by graduate students and advanced researchers alike. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
29.
Darcy A. Davis Nitesh V. Chawla Nicholas A. Christakis Albert-László Barabási 《Data mining and knowledge discovery》2010,20(3):388-415
The monumental cost of health care, especially for chronic disease treatment, is quickly becoming unmanageable. This crisis has motivated the drive towards preventative medicine, where the primary concern is recognizing disease risk and taking action at the earliest signs. However, universal testing is neither time nor cost efficient. We propose CARE, a Collaborative Assessment and Recommendation Engine, which relies only on patient’s medical history using ICD-9-CM codes in order to predict future disease risks. CARE uses collaborative filtering methods to predict each patient’s greatest disease risks based on their own medical history and that of similar patients. We also describe an Iterative version, ICARE, which incorporates ensemble concepts for improved performance. Also, we apply time-sensitive modifications which make the CARE framework practical for realistic long-term use. These novel systems require no specialized information and provide predictions for medical conditions of all kinds in a single run. We present experimental results on a large Medicare dataset, demonstrating that CARE and ICARE perform well at capturing future disease risks. 相似文献
30.
The authors do not see any benefit to J. C. Coyne. R. Thompson, and V. Whiffen's (2004) proposal to draw sharp boundaries between psychodynamic vulnerability theories, research on the onset of syndromal depression, and research with vulnerable, nondepressed populations. These domains have been and remain mutually relevant. Coyne et al. did not bring forward new evidence concerning the 6 issues addressed by D. C. Zuroff. M. Mongrain. and D. A. Santor (2004); consequently, the authors stand by their conclusions. According to Lakatos (as cited in B. Gholson & P. Barker. 1985), scientists justifiably continue to invest in research programs as long as the programs remain progressive. The personality vulnerability program is theoretically and empirically progressive and merits continued investment. Nevertheless, the field would benefit if Coyne et al. articulated a systematic contextualist research program to compete with the personality research program. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献