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71.
As rivers warm, cold‐water fish species may alleviate thermal stress by moving into localized thermal refuges such as cold‐water plumes created by cool tributary inflows. We quantified use of two tributary confluence plumes by juvenile steelhead, Oncorhynchus mykiss, throughout the summer, including how trout positioned themselves in relation to temperature within confluence plumes. At two confluences, Cedar and Elder creeks, along the South Fork Eel River, California, USA, we monitored temperatures using in situ logger grids throughout summer 2016. Fish were counted within confluences via snorkel surveys five times a day on 5 days at each site. We found diel and seasonal dependence on confluence use by steelhead, especially at the Cedar Creek confluence, where mainstem temperatures exceeded 28°C. At this site, fish moved into the confluence on the warmest days and warmest times of the day. Fish observed within the Cedar Creek confluence plume were most common in locations between 20–22°C, rather than the coldest locations (14.5°C). At Elder Creek, where mainstem temperatures remained below 24°C, there was little relationship between mainstem temperature and steelhead presence in the confluence plume. At both sites, steelhead distribution within plumes was influenced by spatial variation of temperature and mean temperature in surveyed grid cells. Our results show that cool tributaries flowing into warmer mainstem reaches (over 24°C) likely create important thermal refuges for juvenile steelhead. As mainstem rivers warm with climate change, cool‐water tributary inputs may become more important for sustaining cold‐water salmonids near the southern end of their range.  相似文献   
72.
Mycobacterium tuberculosis (Mtb) represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the Mtb antigens TB10.4 and Ag85B. In mice, rLCMV elicited high frequencies of polyfunctional Mtb-specific CD8 and CD4 T cell responses. CD8 but not CD4 T cells were efficiently boosted upon vector re-vaccination. High-frequency responses were also observed in neonatally vaccinated mice, and co-administration of rLCMV with Expanded Program of Immunization (EPI) vaccines did not result in substantial reciprocal interference. Importantly, rLCMV immunization significantly reduced the lung Mtb burden upon aerosol challenge, resulting in improved lung ventilation. Protection was associated with increased CD8 T cell recruitment but reduced CD4 T cell infiltration upon Mtb challenge. When combining rLCMV with BCG vaccination in a heterologous prime-boost regimen, responses to the rLCMV-encoded Mtb antigens were further augmented, but protection was not significantly different from rLCMV or BCG vaccination alone. This work suggests that rLCMV may show utility for neonatal and/or adult vaccination efforts against pulmonary tuberculosis.  相似文献   
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Shared book reading, and the conversation that accompanies it, can facilitate young children's vocabulary growth. To identify the features of extratextual questions that help 3-year-olds learn unfamiliar words during shared book reading, two experiments explored the impact of cognitive demand level, placement, and an approximation to scaffolding. Asking questions about target words improved children's comprehension and production of word–referent associations, and children with larger vocabularies learned more than children with smaller vocabularies. Neither the demand level nor placement of questions differentially affected word learning. However, an approximation to scaffolding, in which adults asked low demand questions when words first appeared and high demand questions later, did facilitate children's deeper understanding of word meanings as assessed with a definition task. These results are unique in experimentally demonstrating the value for word learning of shifting from less to more challenging input over time. Discussion focuses on why a scaffolding-like procedure improves children's acquisition of elaborated word meanings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Up to 37% of individuals experience chronic pain during their lifetimes. Approximately one fourth of primary care patients with chronic pain also meet criteria for major depression. Many of these individuals fail to receive psychotherapy or other treatment for their depression; moreover, when they do, physical pain is often not addressed directly. Women, socioeconomically disadvantaged individuals, African Americans, and Latinos all report higher rates of pain and depression compared with other groups. This article describes a version of interpersonal psychotherapy tailored for patients with comorbid depression and chronic pain, interpersonal psychotherapy for depression and pain (IPT-P). IPT-P potentially could be delivered to many patient populations in a range of clinical settings, but this article focuses on its delivery within primary care settings for socioeconomically disadvantaged women. Adaptations include a brief 8-session protocol that incorporates strategies for anticipating barriers to psychotherapy, accepting patients' conceptualization of their difficulties, encouraging patients to consider the impact of their pain on their roles and relationships, emphasizing self-care, incorporating pain management techniques, and flexible scheduling. In addition, IPT-P is designed as an adjunct to usual medical pain treatment, and seeks to engage non–treatment-seeking patients in psychotherapy by focusing on accessibility and relevance of the intervention to concerns common among patients with pain. Identifying patients with comorbid depression and chronic pain and offering IPT-P as a treatment option have the potential to improve clinical outcomes for individuals with depression and chronic pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Although street sweeping is commonly regarded as a cost-effective storm-water best management practice, there is little quantitative evidence that street sweeping directly improves runoff water quality. In this paper, several previous street sweeping studies were reevaluated using statistical power analysis. Two-group, independent-sample one-sided t-test power analyses were performed using log-transformed event mean concentrations (EMCs) of total suspended solids, suspended sediment concentration or chemical oxygen demand. The effect size between the two groups was estimated using the sweepers’ pickup efficiency, which showed that the failure to detect the difference between mean EMCs of the two sample groups (i.e., unswept and swept groups) is likely due to limited sample numbers. Too few samples, which also resulted in a high coefficient of variation, were analyzed to detect the likely difference between swept and unswept observations. In addition, the temporal gap between street sweeping and subsequent storm events was not controlled to improve statistical power.  相似文献   
79.
At a moment when standardization dominated housing design discussions, Italians engaged in a different kind of experiment in housing production. Under the Ina-Casa plan (1949–63), Italian architects developed a slow approach to architecture. Like its contemporaries, the plan grew out of a desire to provide affordable homes for the working class in the postwar period. But the primary goal of the Ina-Casa plan was creating jobs. The brainchild of the Minister of Labor and Social Security, Amintore Fanfani, the Ina-Casa plan was designed to put thousands of unemployed Italians back to work in the wake of the social upheaval and physical devastation wrought by World War II. The success of the plan was measured in terms of workdays created as well as in numbers of homes. Consequently, traditional methods and materials of construction—often rejected for being labor intensive—were embraced under the Ina-Casa plan as an effective way to create more jobs.  相似文献   
80.
Electronic excitation of a probe chromophore can lead to a change in dipole moment that influences its activity or solubility in solution and changes its relative affinity for partitioning between two phases. Photoexcitation of a probe molecule can, therefore, perturb a sorption equilibrium, and the relaxation kinetics of the probe to the new equilibrium conditions can be monitored in a time-resolved luminescence experiment. The adsorption/desorption kinetics of rose bengal, distributed between a C-18 derivatized porous-silica surface and a liquid mobile-phase solution, were investigated. These kinetics were determined by observing their effect on the phosphorescence decay of the triplet state of rose bengal and its quenching by ferricyanide. The methanol/water solvent compositions were varied to alter the fraction of adsorbed rose bengal. The adsorption rate constant for the triplet state was determined from the dependence of the phosphorescence relaxation rate on dye concentration in solution. The results indicate that the adsorption kinetics are diffusion controlled and that the relaxation is influenced by efficient triplet-energy transfer between excited- and ground-state rose bengal at the C-18 silica/solution interface.  相似文献   
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