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991.
Jeffrey T. Rominger Anne F. Lightbody Heidi M. Nepf 《Canadian Metallurgical Quarterly》2010,136(12):994-1002
Vegetation was added to a fully developed sandy point bar in the meander of a constructed stream. Significant changes in the flow structure and bed topography were observed. As expected, the addition of vegetative resistance decreased the depth-averaged streamwise velocity over the bar and increased it in the open region. In addition, the secondary circulation increased in strength but became confined to the deepest section of the channel. Over the point bar, the secondary flow was entirely outward, i.e., toward the outer bank. The changes in flow led to changes in bar shape. Although the region of the bar closest to the inner bank accumulated sediment, erosion of the bar and the removal of plants by scouring were observed at the interface between the planted bar and the open channel. 相似文献
992.
Dejoie C Martinetto P Dooryhée E Van Elslande E Blanc S Bordat P Brown R Porcher F Anne M 《Applied spectroscopy》2010,64(10):1131-1138
The durability of an organic color and its resistance against external chemical agents and exposure to light can be significantly enhanced by hybridizing the natural dye with a mineral. In search for stable natural pigments, the present work focuses on the association of indigo blue with several zeolitic matrices (LTA zeolite, mordenite, MFI zeolite). The manufacturing of the hybrid pigment is tested under varying oxidizing conditions, using Raman and ultraviolet-visible (UV-Vis) spectrometric techniques. Blending indigo with MFI is shown to yield the most stable composite in all of our artificial indigo pigments. In the absence of defects and substituted cations such as aluminum in the framework of the MFI zeolite matrix, we show that matching the pore size with the dimensions of the guest indigo molecule is the key factor. The evidence for the high color stability of indigo@MFI opens a new path for modeling the stability of indigo in various alumino-silicate substrates such as in the historical Maya Blue pigment. 相似文献
993.
John E. Nealy Ryan B. Norman Steve R. Blattnig Anne M. Adamczyk 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(15):2415-238
A deterministic computational procedure for describing the transport of electrons in condensed media is formulated to simulate the effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The primary purpose for developing the procedure is to provide a means of rapidly performing numerous repetitive transport calculations essential for electron radiation exposure assessments for complex space structures. The present code utilizes well-established theoretical representations to describe the relevant interactions and transport processes. A combined mean free path and average trajectory approach is used in the transport formalism. For typical space environment spectra, several favorable comparisons with Monte Carlo calculations are made which have indicated that accuracy is not compromised at the expense of the computational speed. 相似文献
994.
Reviews the book, Climate, affluence, and culture by Evert Van de Vliert (see record 2009-01826-000). The book provides an interesting analysis of the intersection between climate, culture, and economic factors. Van de Vliert observes that most scholars move from cultures toward climate and economies, whereas his interest is in the opposite direction—from climates and economies toward cultures. He contends that, since we have created global warming and local poverty, world cultures can also work to solve these threats to humanity, if we address them together rather than separately. Both poverty and climate must be addressed together since their interrelatedness means that focusing on one at the expense of the other would only lead to further problems down the road. Van de Vliert asserts that we have the opportunity to prove that regions lacking water, food, and money need not become “hot spots for conflicts and other malice” and declares that we need to make these ethical choices soon. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Simons Anne D.; Padesky Christine A.; Montemarano Jeremy; Lewis Cara C.; Murakami Jessica; Lamb Kristen; DeVinney Sharon; Reid Mark; Smith David A.; Beck Aaron T. 《Canadian Metallurgical Quarterly》2010,78(5):751
Objective: In this study, the authors examined the feasibility and effectiveness of training community therapists to deliver cognitive behavior therapy (CBT) for depression. Method: Participants were therapists (n = 12) and clients (n = 116; mean age = 41 years, 63% women) presenting for treatment of depression at a not-for-profit and designated community mental health center for St. Joseph County, Indiana. The training model included a 2-day workshop followed by 1 year of phone consultations. CBT competence ratings from the Cognitive Therapy Scale were obtained prior to training and at 6 and 12 months posttraining. Two different groups of clients, a treatment-as-usual (TAU) group (n = 74) and a CBT group (n = 42), were compared with respect to decrease in symptoms of depression (assessed with the Beck Depression Inventory) and anxiety (assessed with the Beck Anxiety Inventory). Results: Therapists showed significant increases in total scores from pretraining to 6 months posttraining, increases that were maintained at 12 months. The increase in the total score reflected gains on items that specifically measure CBT skills and structure. Although both TAU and CBT resulted in a significant decrease in depressive symptoms, the CBT clients showed significantly greater change than the TAU clients, F(2, 113) = 53.40, p 相似文献
996.
Martijn Carolien; Vanderlinden Marlies; Roefs Anne; Huijding Jorg; Jansen Anita 《Canadian Metallurgical Quarterly》2010,29(5):514
Objective: Many women show weight and body concerns that leave them vulnerable to body dissatisfaction, lowered self-esteem, psychological distress, and eating disorders. This study tested whether body satisfaction could be increased by means of evaluative conditioning. Design: In the experimental condition (n = 26), women with low and high body concern completed a conditioning procedure in which pictures of their bodies were selectively linked to positive social stimuli (pictures of smiling faces). Pictures of control bodies were linked to neutral or negative social stimuli (neutral and frowning faces). In a control condition (n = 28), low and high body concerned women underwent a procedure in which pictures of their own body and of control bodies were randomly followed by positive, neutral, and negative social stimuli. Main Outcome Measures: Changes in body satisfaction and self-esteem before and after the conditioning task. Results: Women with high body concern demonstrated an increase in body satisfaction and global self-esteem when pictorial representations of their own bodies were associated with positive stimuli that signaled social acceptance. Conclusion: A simple conditioning procedure increased body satisfaction in healthy, normal weight women who were concerned about their shape and weight. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Cochran Jeff L.; Cochran Nancy H.; Nordling William J.; McAdam Anne; Miller Deborah T. 《Canadian Metallurgical Quarterly》2010,19(3):130
This article presents two cases with strong evidence measures in which child-centered play therapy (CCPT) was provided for children referred for highly disruptive behavior, including attention problems and aggression. Apparent progress was evidenced on the Teacher Report Form (TRF) of the Child Behavior Checklist (Achenbach & Rescorla, 2001). One client had a waiting period equal to his treatment period in which ratings were stable before change across his treatment period. The cases provide opportunities to consider how CCPT may work differently for similar behavioral difficulties in individual children. Researchers conceptualized each client's areas of difficulty and apparent treatment effects as an expert panel, aided by indications from the TRF. Individual discussions are provided regarding rationales for apparent progress and why CCPT seemed to have been effective. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Satyanarayana Kosaraju Venu Gopal Anne 《先进制造进展(英文版)》2013,1(4):329-339
Machining titanium is one of ever-increasing magnitude problems due to its characteristics such as low thermal conductivity, modulus of elasticity and work
hardening. The efficient titanium alloy machining involves a proper selection of process parameters to minimize the tangential force (Fz) and surface roughness (Ra). In the present work, the performance of PVD/TiAlN coated carbide inserts was investigated using response surface methodology (RSM) for turning Ti-6Al-4V. The effects of process parameters such as speed (v), feed (f), depth of cut (d) and back rake angle (γy) on Fz and Ra were investigated.
The experimental plan used for four factors and three levels was designed based on face centered, central composite design (CCD). The experimental results indicated that Fz increased with the increase in d, f and decreased with the increase in v and γy, whereas Ra decreased with the increase in v and γy, and increased with d and v. The goodness of fit of the regression equations and model fits (R 2) for Fz and Ra were found to be 0.968 and 0.970, which demonstrated that it was an effective model. A confirmation test was also conducted in order to verify the correctness of the model. 相似文献
999.
Maty Anne Beecher 《Architectural Design》2008,78(3):54-59
Mary Anne Beecher's discussion of Aubrey Watzek's house extends traditional notions of regionalism to the domain of the interior. She outlines numerous ways that the local landscape and history figure as condensed renditions within rooms, surfaces and details. It is here that we find evidence of interior atmosphere developed as identity within a specific cultural and geographical context. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
1000.
Catalina Medrano-Galarza Stephen J. LeBlanc Andria Jones-Bitton Trevor J. DeVries Jeffrey Rushen Anne Marie de Passillé Marcia I. Endres Derek B. Haley 《Journal of dairy science》2018,101(3):2293-2308
Data on management practices used with automated milk feeders (AMF) are needed to identify factors associated with calf health in these systems. The objectives of this observational, longitudinal, cross-sectional study were to estimate the prevalence of calf diarrhea (CD) and bovine respiratory disease (BRD), and to identify factors associated with prevalence of these diseases at the pen level on dairy farms feeding milk to group-housed calves with AMF. Seventeen dairy farms with AMF in Ontario, Canada, were visited 4 times, seasonally, over 1 yr. The clinical health of all calves (n = 1,488) in pens (n = 35) with AMF was scored to identify the number of calves with CD and BRD. Data on calf, feeder, and pen management practices were analyzed using generalized linear mixed regression models for each disease. Overall calf-level prevalence of CD and BRD were 23 and 17%, respectively. Median (interquartile range, IQR) within-pen prevalence of CD and BRD were 17% (7 to 37%) and 11% (0 to 28%), respectively. Median age (IQR) for diarrheic calves was 25 d (16 to 42 d), and for calves with BRD was 43 d (29 to 60 d). Factors associated with lower within-pen prevalence of CD were the administration of vitamin E and selenium at birth [odds ratio (OR) = 0.56; 95% confidence interval (CI): 0.32 to 0.99], feeding of probiotics (OR = 0.44, 95% CI: 0.22 to 0.93), and adding fresh bedding every 2 to 3 d (OR = 0.43; 95% CI: 0.24 to 0.76) compared with every 7 or more days. In contrast, sharing air with older cattle (>9 mo old) was associated with increased within-pen prevalence of CD (OR = 4.54, 95% CI: 1.88 to 10.52). Additionally, total bacteria counts ≥100,000 cfu/mL in milk samples taken from the AMF mixing jar were associated with increased within-pen prevalence of CD during the summer visit (OR = 3.34; 95% CI: 1.31 to 8.54). Increased total solids in milk or milk replacer (OR = 0.48, 95% CI: 0.27 to 0.85) and feeding whole milk versus milk replacer (OR = 0.29, 95% CI: 0.11 to 0.75) were associated with lower within-pen prevalence of BRD. Factors associated with greater within-pen prevalence of BRD were sharing air with weaned cattle up to 8 mo old (OR = 3.21, 95% CI: 1.26 to 8.16), and greater depth of the wet bedding pack. The use of maternity pens for reasons other than just calving was associated with increased prevalence of both CD and BRD (OR = 1.85, 95% CI: 1.03 to 3.33; OR = 2.61, 95% CI: 1.21 to 5.58, respectively). These results suggest that isolation from older animals and frequent cleaning of the feeder and pen may help to reduce disease prevalence in group-housed calves fed with an AMF. 相似文献