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81.
Previous research has examined protective behavioral strategies (PBS), or cognitive-behavioral strategies that may be employed when using alcohol to reduce consumption and related problems, as an important predictor of alcohol use and alcohol-related problems. More recently, studies have explored the mediating and moderating role of PBS on the relationships between key alcohol-related risk factors (i.e., drinking motives, depressive symptoms, binge drinking) and alcohol problems; however, current research examining PBS as a moderator of the relationship between alcohol use and related problems has methodological limitations. The purpose of the present study was to extend previous literature to examine the moderating effect of PBS on the relationship between binge drinking and alcohol-related problems. Data were collected and analyzed from 4,154 students at 13 midwestern universities. Findings indicated that PBS moderated the binge drinking-alcohol problems relationship for each of the four measures of binge drinking. However, effects were strongest when binge drinking was measured dichotomously versus continuously. Implications and future directions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
82.
A novel osmotic microbial fuel cell (OsMFC) was developed by using a forward osmosis (FO) membrane as a separator. The performance of the OsMFC was examined with either NaCl solution or artificial seawater as a catholyte (draw solution). A conventional MFC with a cation exchange membrane was also operated in parallel for comparison. It was found that the OsMFC produced more electricity than the MFC in both batch operation (NaCl solution) and continuous operation (seawater), likely due to better proton transport with water flux through the FO membrane. Water flux from the anode into the cathode was clearly observed with the OsMFC but not in the MFC. The solute concentration of the catholyte affected both electricity generation and water flux. These results provide a proof of concept that an OsMFC can simultaneously accomplish wastewater treatment, water extraction (from the wastewater), and electricity generation. The potential applications of the OsMFC are proposed for either water reuse (linking to reverse osmosis for reconcentration of draw solution) or seawater desalination (connecting with microbial desalination cells for further wastewater treatment and desalination).  相似文献   
83.
Carbon dioxide is the most important greenhouse gas other than water vapor, and its modulation by the biosphere is of fundamental importance to our understanding of global climate change. We have developed a new technique for vertical profiling of CO2 and meteorological parameters through the atmospheric boundary layer and well into the free troposphere. Vertical profiling of CO2 mixing ratios allows estimates of landscape-scale fluxes characteristic of approximately100 km2 of an ecosystem. The method makes use of a powered parachute as a platform and a new Tedlar bag air sampling technique. Air samples are returned to the ground where measurements of CO2 mixing ratios are made with high precision (< or =0.1%) and accuracy (< or =0.1%) using a conventional nondispersive infrared analyzer. Laboratory studies are described that characterize the accuracy and precision of the bag sampling technique and that measure the diffusion coefficient of CO2 through the Tedlar bag wall. The technique has been applied in field studies in the proximity of two AmeriFlux sites, and results are compared with tower measurements of CO2.  相似文献   
84.
Twin studies from the Minnesota Twin Family Study (MTFS) suggest negligible genetic effects on eating pathology before puberty but increased genetic effects during puberty. However, an independent study found no pubertal differences in genetic and environmental effects (R. Rowe, A. Pickles, E. Simonoff, C. M. Bulik, & J. L. Silberg, 2002). Discrepant results may be due to methodological differences. The MTFS studies divided twins at mid-puberty, whereas R. Rowe et al. (2002) divided twins based on menarche alone. In the present study, the authors aimed to reconcile discrepant findings by examining differences in etiologic effects for disordered eating attitudes and behaviors (i.e., levels of weight preoccupation, body dissatisfaction, binge eating, compensatory behaviors) using both classification methods in a new sample of 656 female twins. Using the MTFS method (i.e., K. L. Klump, M. McGue, & W. G. Iacono, 2003), the authors observed nominal genetic effects in prepubertal twins but significant genetic effects in pubertal and young adult twins. Conversely, genetic effects were moderate and equal in all groups using the R. Rowe et al. (2002) method. Findings highlight the potentially important role of puberty in the genetic diathesis of disordered eating attitudes and behaviors and the need to use early indicators of pubertal status in studies of developmental effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
Although previous research has demonstrated increased relationship distress and separation for cohabiting couples, little is known about specific problems cohabiting individuals encounter in comparison to dating and married individuals. This study examines open-ended reports of 1,252 individuals' (220 dating, 231 cohabiting, and 801 married) relationship concerns using a detailed, reliable coding system. The top 5 areas considered most problematic by cohabiting individuals were problems in specific areas of their current relationship, individual problems, general communication, arguments, and emotional affection–distance. Dating and cohabiting individuals reported similar frequencies of global problems except that cohabiting individuals reported more problems with arguments and fewer problems with relationship commitment. Married and cohabiting individuals had more differences in their reports of relationship concerns; results suggested that cohabiting relationships tended to be both more vibrant and more volatile than marital relationships. However, most differences between relationship types were no longer significant after controlling for individuals' relationship and demographic characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
This study evaluated the effectiveness of comprehension training embedded in a program that taught science content to 2nd graders. The program included instruction about the structure of compare-contrast expository text, emphasizing clue words, generic questions, graphic organizers, and the close analysis of well-structured text exemplars. This program was compared with a program that focused on the science content but included no compare-contrast training as well as with a no-instruction control. Regular classroom teachers (14 from 4 schools), randomly assigned to treatment, provided the instruction; 215 students (7-8 years old) participated. The study replicated acquisition and transfer effects found in an earlier study, that is, transfer to compare-contrast text with content related and unrelated to the instructional content (with no loss in the amount of science content acquired). The program also led to better performance on written and oral response measures and on 1 of the 2 measures involving authentic (less well-structured) compare-contrast text. These findings support and extend previous findings that explicit instruction in comprehension is effective as early as the primary-grade level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Objective: To examine cardiovascular reactivity and recovery to laboratory stress among a naturalistic sample of individuals diagnosed with major depressive disorder (MDD) and healthy control participants. Prospective evidence suggests that MDD confers risk for cardiovascular disease equal to or greater than the risk associated with depressed mood. Enhanced cardiovascular reactivity has been proposed as a mechanism explaining increased risk, but data are inconsistent as to whether depressed individuals exhibit enhanced or attenuated reactivity. Further, few studies have examined appraisal and recovery differences. Design: Participants diagnosed with MDD (N = 25) and healthy control participants (N = 25) engaged in a cardiovascular reactivity protocol including 2 tasks, each followed by a brief recovery period. Main outcome measures: Blood pressure, heart rate, pre-ejection period, cardiac output and total peripheral resistance were assessed. Appraisals of tasks were assessed prior to each task. Results: Depressed participants exhibited significantly less systolic blood pressure, heart rate, and cardiac output reactivity during speech, less heart rate reactivity during mirror tracing, and less heart rate recovery after speech and mirror tracing than controls. Depressed participants appraised the tasks as more demanding, threatening, and stressful and reported being less able to cope than controls. Appraisals were related to heart rate reactivity, but appraisals did not mediate the relationship between depression group and reactivity. Conclusion: Impaired recovery rather than exaggerated cardiovascular reactivity may partially explain the increased prospective cardiovascular disease risk in depressed individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
The city of New Orleans, LA was severely impacted by flooding and wind damage following landfall of Hurricane Katrina in August 2005. The city's drinking water infrastructure was severely compromised and massive amounts of sediment were redeposited throughout the flooded region. Thousands of homes were water-damaged resulting in the rapid growth of mold. In September and October 2005 a convenience sample of selected homes, tap water, surface water, and sediment within New Orleans was assessed for mold contamination, microbial contamination, and heavy metal concentrations. At selected sites, indoor mold spore concentrations were compared to outdoor concentrations. The purpose of this study was to conduct a baseline environmental assessment in an effort to identify public health threats caused by wind and flood damage. Surface waters contained high concentrations of bacterial indicators whereas no bacteria were detected in tap water, even from taps containing no chlorine residual. Sediment samples contained concentrations of lead and arsenic similarto pre-Katrina concentrations. Outdoor total spore (sp) concentrations ranged from >6500 to 84 713 sp/m(3). Indoor concentrations ranged from 6142 to 735 123 sp/m(3). For the 13 locations with matched indoor/ outdoor samples, the mean indoor/outdoor spore ratio was 4.11 (ranging from 0.27 to >11.44). Inside 5 of the 13 homes, total spore counts/m(3) exceeded 100 000, with measurements in the moldiest home exceeding 700 000 sp/ m(3). In conclusion, surface waters had high concentrations of bacterial contamination but no bacterial indicators were present in tap water. Sediment samples did not have appreciable increases in lead or arsenic. Flooded homes, however, contained substantial concentrations of mold which could present a public health exposure route to individuals repopulating and restoring the City of New Orleans.  相似文献   
89.
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration, both of which increase the risk and accelerate the progression of Alzheimer’s disease (AD). The gut microbiome is an essential modulator of the immune system, impacting the brain. AD has been related with reduced diversity and alterations in the community composition of the gut microbiota. This study aimed to determine whether the gut microbiota from AD mice exacerbates neurological deficits after TBI in control mice. We prepared fecal microbiota transplants from 18 to 24 month old 3×Tg-AD (FMT-AD) and from healthy control (FMT-young) mice. FMTs were administered orally to young control C57BL/6 (wild-type, WT) mice after they underwent controlled cortical impact (CCI) injury, as a model of TBI. Then, we characterized the microbiota composition of the fecal samples by full-length 16S rRNA gene sequencing analysis. We collected the blood, brain, and gut tissues for protein and immunohistochemical analysis. Our results showed that FMT-AD administration stimulates a higher relative abundance of the genus Muribaculum and a decrease in Lactobacillus johnsonii compared to FMT-young in WT mice. Furthermore, WT mice exhibited larger lesion, increased activated microglia/macrophages, and reduced motor recovery after FMT-AD compared to FMT-young one day after TBI. In summary, we observed gut microbiota from AD mice to have a detrimental effect and aggravate the neuroinflammatory response and neurological outcomes after TBI in young WT mice.  相似文献   
90.
正在距北京三十英里的地方,一个由200多名具有国际知名度的中国艺术家组成的社区,缺乏一个互动吸引点、艺术展示区或接待场所。一个由艺术家、评论家和代理人组成的财团收购了一处地产,准备为通州的艺术组织建设一个这样的项目。这是一个分期项目,已完工的首期是门楼,包括定居在此的艺术家们的住房和工作室。项目场址被一堵现有的砖墙隔开,一边是一片树林,另一边是一片贫瘠的工业场  相似文献   
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