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991.
Jane Clary Marcus Quigley Aaron Poresky Andrew Earles Eric Strecker Marc Leisenring Jonathan Jones 《Canadian Metallurgical Quarterly》2011,137(3):190-198
Low impact development (LID) strategies are being encouraged in many communities as an approach to reduce potential adverse impacts of development on receiving streams. Many questions exist regarding how well various LID strategies perform in different settings, just as similar questions have been raised regarding performance of traditional stormwater best management practices (BMPs). Whereas historical focus on BMP performance has been water quality concentrations or loads, characterization of volume reduction benefits for both conventional and LID practices is increasingly an objective of researchers and stormwater managers. More than a decade ago, Urban Water Resources Research Council (UWRRC) members worked to develop a set of standardized monitoring and reporting protocols for traditional BMPs and to establish a master database for the purpose of evaluating BMP performance and the factors affecting performance. This effort culminated in the International Stormwater BMP Database (www.bmpdatabase.org), which contains data for more than 360 BMPs and continues to operate as a clearinghouse for stormwater BMP data and performance analyses. During 2008–2009, the International Stormwater BMP Database project expanded to better integrate LID into the database and develop a set of metrics that can be used to characterize BMP performance with regard to surface runoff volume reduction. This paper provides a condensed overview and progress report on the LID-focused effort, including the following topics: (1)?monitoring guidance for LID at the overall site development level, (2)?an overview of recent changes to the International Stormwater BMP Database to better accommodate LID studies, (3)?a summary of LID studies currently included in the database, and (4)?a proposed approach for evaluating performance of LID studies with regard to reducing surface runoff volumes. 相似文献
992.
993.
Shaw and his colleagues [Shaw, B., Han, J., Kim, E., Gustafson, D., Hawkins, R., Cleary, C., et al. (2007). Effects of prayer and religious expression within computer support groups on women with breast cancer. Psycho-oncology, 16(7), 676–687] examined religious expression in breast cancer (BC) online support groups (OSG). Using Pennebaker’s LIWC text analysis to assess religious expression, they found that the more frequent the expression of words related to religion the lower the levels of negative emotions and the higher the levels of health self-efficacy and functional well-being. Our study goal was to replicate their findings. Specifically, we tested their central hypothesis that the percentage of religious words written by members of BC OSG’s are associated with improvement in psychological outcomes. Five BC OSG’s from our previous work [Lieberman, M. A., & Goldstein, B. (2005a). Not all negative emotions are equal: The role of emotional expression in online support groups for women with breast cancer. Psycho-oncology. 15, 160–168; Lieberman, M. A., & Goldstein, B. (2005b). Self-help online: An outcome evaluation of breast cancer bulletin boards. Journal of Health Psychology, 10(6), 855–862] studied 91 participants at baseline and 6 months post. Significant changes in depression and quality of life was found over time. In the current study linear regressions examined the relationship between religious statements and outcomes. The results did not support the hypotheses of a positive relationship between religious expression and positive outcome in both OSG samples. Reviews of studies examining the role of religion in health outcomes report equivocal results on the benefits of religious expression. 相似文献
994.
Singular perturbation techniques are used to investigate the linear eigenvalue problem that describes the partial wrinkling of a pre-stressed rectangular thin elastic plate under in-plane bending. The dependence of the critical load and the wavelength of the localised oscillatory pattern on the non-dimensional bending rigidity of the plate is captured with a higher-order boundary-layer analysis. Comparisons with direct numerical simulations of the original eigenproblem confirm the accuracy and versatility of the asymptotic technique explored in this work. 相似文献
995.
Alok Gupta Boris Jukic Mingzhi Li Dale O. Stahl Andrew B. Whinston 《Computational Economics》2001,17(2-3):203-218
We investigate two parametric approaches and one non-parametric approach toestimating Internet users' value-of-time, an important characteristic ofdemand for Internet services. The advantages of these approaches are madeclear and their limitations discussed. The models are tested with datagenerated from our similation model of the Internet economy. Given thecharacteristics of the data, we investigate parametric count-data modelsfirst. While reasonably good results are obtained on all medium- andlarge-sized jobs, the method fails on small-sized ones. Second, we develop anonparametric quasi-Bayesian update algorithm for retrieving the underlyingdistribution function of Internet users' value-of-time purely fromobservations on their choices. Compared with the parametric count-data models,good results are obtained in every case. 相似文献
996.
Male therapists' clinical bias: Influence of client gender roles and therapist gender role conflict.
This study examined male therapists' gender role conflict, client sexual orientation, and client emotional expression as they interrelated with clinical judgments about male clients. Using a series of written clinical vignettes to manipulate the client variables of sexual orientation and emotional expression, 196 experienced male therapists completed a measure of male gender role conflict, read a clinical vignette varying the client's sexual orientation and emotional expression, and rated the client on several clinical dimensions. Canonical analysis revealed 2 roots indicating that therapist gender role conflict factors, in combination with client sexual orientation and emotional expression, were associated with therapists' ratings of the male client's prognosis and how much therapists liked, had empathy for, had comfort with, and had willingness to see the male client. Implications for counseling practice, limitations, and future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
A system was devised which allows particles to remain in suspension in a conventional 60 L aquarium without undue disturbance to resident fish. Using this system, juvenile rainbow trout were exposed for one week to 4-tert-octylphenol (OP, 10-1000 μg/L) with or without the presence of suspended sediments (10-20 mg/L of natural suspended sediments from the River Calder, UK). About 8% of the added OP partitioned to the solid phase. Vitellogenin levels were determined in the plasma of the exposed rainbow trout and showed a dose-dependent increase with regards to OP exposure concentration. Considerable variation in the vitellogenin response was observed between separate runs with the same OP concentration. There was no statistically significant (at P < 0.05) difference in plasma VTG levels between the OP treatments with or without suspended sediments. This suggests that the dissolved concentration is the key factor and natural suspended sediment neither protects against, nor exacerbates, the endocrine disrupting effect of OP on fish. 相似文献
998.
One of the causes of organoleptic changes in milk, lipid peroxidation, has been monitored by a sensitive assay newly applied to foodstuffs. It has been shown that even at medium radiation doses (up to 3600 Gy) negligible lipid peroxidation takes place, providing the milk is thoroughly gassed with nitrogen. Using a test spoilage microorganism, Pseudomonas aeruginosa (Schroeter), it was shown that the D10 was 35 Gy in air and 105 Gy under anaerobic conditions. Dose/survival curves indicate that 5 decades of killing needed 200 Gy in air and 600 Gy under nitrogen. However, even after receiving a dose of 1600 Gy, both aerobically and anaerobically treated milk failed the methylene blue test at 21 days post-irradiation. The data indicate that, although the deleterious lipid peroxidation effects of irradiation can be minimised by the removal of air, this in turn results in a degree of protection being afforded to the bacteria, and that doses in excess of 1600 Gy are needed to effectively sterilise milk. 相似文献
999.
The production and stability of glyoxylic acid was followed during the storage of tartaric acid solutions under various conditions. The solutions were prepared both with and without ethanol. Quantification of glyoxylic acid and other oxidation products, including hydrogen peroxide and formic acid, were performed using ion exclusion chromatography. Glyoxylic acid was only detected in tartaric acid samples that had been stored outdoors and sunlight was identified as the critical component of outdoor storage that allowed its formation. The hydrogen peroxide and glyoxylic acid generated under these conditions were of limited stability due to their reaction with each other to produce formic acid. The concentration of the glyoxylic acid was greatly increased when ethanol was omitted from the sample matrix. Copper(II) enhanced the stability of glyoxylic acid but slowed its production. The reaction pathway responsible for the sunlight-induced production and subsequent stability of glyoxylic acid is discussed. 相似文献
1000.
During, or following, the fabrication of a microelectronic device, it is possible for the material phases at critical interfaces
to react with one another, and so alter the elec-trical performance. This is particularly important for metallization contacts
to semi-conductors and for multilevel interconnects. The present article shows that application of phase diagram principles
can successfully predict the mutual stability or chemical reactivity in such circumstances. Since most relevant phase diagrams
are not available, it is shown how they may be calculated from known thermochemical data, or deduced from observations on
thin-film reactions. The article is illustrated by the behavior of titanium silicide with a diffusion barrier layer (TiN)
and the surrounding dielectric SiO2. In addition the Al-Si-O-N and W-N-Ga-As systems are described, and metastable amor-phous phase formation at the Ti-Si interface
is discussed. 相似文献