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991.
This and the companion article summarize linear and nonlinear structural identification (SI) methods using a pattern recognition technique, support vector regression (SVR). Signal processing plays a key role in the SI field, because observed data are often incomplete and contaminated by noise. Support vector regression (SVR) is a novel data processing technique that is superior in terms of its robustness, thus it has the potential to be applied for accurate and efficient structural identification. Three SVR-based methods employing the autoregression moving average (ARMA) time series, the high-order AR model, and the sub-structuring strategy are presented for linear structural parameter identification using observed vibration data. The SVR coefficient selection and incremental training algorithm have also been presented. Numerical evaluations demonstrate that the SVR-based methods identify structural parameters accurately. A five-floor structure shaking table test has also been conducted, and the observed data are used to verify experimentally the novel SVR technique for linear structural identification.  相似文献   
992.
Increases in the prevalence of antibiotic resistant bacteria require new approaches for the treatment of infectious bacterial pathogens. It is now clear that a nanotechnology-driven approach using nanoparticles to selectively target and destroy pathogenic bacteria can be successfully implemented. We have explored this approach by using gold nanorods that have been covalently linked to primary antibodies to selectively destroy the pathogenic Gram-negative bacterium, Pseudomonas aeruginosa. We find that, following nanorod attachment to the bacterial cell surface, exposure to near-infrared radiation results in a significant reduction in bacterial cell viability.  相似文献   
993.
Men have long held the lead in motor-vehicle crashes. However, recent research from a variety of countries indicates that women are closing the gap. The relative increase in females involved in crashes has been associated with an increase in crash exposure. But is it simply that there are more women driving that is causing this increase? Or are there other mediating factors? The main goal of this research effort was to shed some light on this controversy. We found evidence that most of the observed increase in female drivers' fatalities was due to a parallel increase in female driving exposure but that some groups of female drivers (mainly underage female drivers) have become more vulnerable to some risk-taking driving behaviors than others.  相似文献   
994.
Scanning tunneling microscopy (STM) images of self-assembled monolayers of close-packed alkane chains on highly oriented pyrolitic graphite often display an alternating bright and dark spot pattern. Classical simulations suggest that a tilt of the alkane backbone is unstable and, therefore, unlikely to account for the contrast variation. First principles calculations based on density functional theory show that an electronic effect can explain the observed alternation. Furthermore, the asymmetric spot pattern associated with the minimum energy alignment is modulated depending on the registry of the alkane adsorbate relative to the graphite surface, explaining the characteristic moiré pattern that is often observed in STM images with close packed alkyl assemblies.  相似文献   
995.
Atypically organised motor maps have been described in some people with epilepsy and we have modelled this in rats. Our goal is to more fully understand the mechanisms responsible for seizure-induced functional brain reorganisation and to reverse their effects. Here we present an overview of the relationship between neocortical motor maps, seizures, and interictal behaviour. To begin we summarise the observations of atypical motor maps with epilepsy and in animal models following experimentally induced seizures. Our novel experiments have established that motor map expansion is linked to a functional alteration of motor behaviour. Evidence for some of the putative brain mechanisms responsible for motor map size is discussed. Our successes reversing seizure-induced map expansion by two different methods are also briefly reviewed. Lastly, unanswered questions for possible future experimentation are posed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
The purpose of this experiment was to conduct a dismantling study of cognitive processing therapy in which the full protocol was compared with its constituent components--cognitive therapy only (CPT-C) and written accounts (WA)--for the treatment of posttraumatic stress disorder (PTSD) and comorbid symptoms. The intent-to-treat (ITT) sample included 150 adult women with PTSD who were randomized into 1 of the 3 conditions. Each condition consisted of 2 hr of therapy per week for 6 weeks; blind assessments were conducted before treatment, 2 weeks following the last session, and 6 months following treatment. Measures of PTSD and depression were collected weekly to examine the course of recovery during treatment as well as before and after treatment. Secondary measures assessed anxiety, anger, shame, guilt, and dysfunctional cognitions. Independent ratings of adherence and competence were also conducted. Analyses with the ITT sample and with study completers indicate that patients in all 3 treatments improved substantially on PTSD and depression, the primary measures, and improved on other indices of adjustment. However, there were significant group differences in symptom reduction during the course of treatment whereby the CPT-C condition reported greater improvement in PTSD than the WA condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
Understanding the potential effects of increased reliance on wastewater treatment plant (WWTP) effluents to meet municipal, agricultural, and environmental flow requires an understanding of the complex chemical loading characteristics of the WWTPs and the assimilative capacity of receiving waters. Stream ecosystem effects are linked to proportions of WWTP effluent under low-flow conditions as well as the nature of the effluent chemical mixtures. This study quantifies the loading of 58 inorganic constituents (nutrients to rare earth elements) from WWTP discharges relative to upstream landscape-based sources. Stream assimilation capacity was evaluated by Lagrangian sampling, using flow velocities determined from tracer experiments to track the same parcel of water as it moved downstream. Boulder Creek, Colorado and Fourmile Creek, Iowa, representing two different geologic and hydrologic landscapes, were sampled under low-flow conditions in the summer and spring. One-half of the constituents had greater loads from the WWTP effluents than the upstream drainages, and once introduced into the streams, dilution was the predominant assimilation mechanism. Only ammonium and bismuth had significant decreases in mass load downstream from the WWTPs during all samplings. The link between hydrology and water chemistry inherent in Lagrangian sampling allows quantitative assessment of chemical fate across different landscapes.  相似文献   
998.
This efficacy for both employers and employees (young working women 18 to 23 years of age) was undertaken to determine whether culturally acceptable dietary changes in lunches in the workplace and at home could bring about a behavioral change and improvement in their iron-deficiency anemia status. Maximum weight was given to increasing consumption of iddli, a popular cereal-based-fermented food, or of gooseberry juice. Four small factories were selected in periurban Bangalore, with a sample of 302 women. The 180-day interventions were supervised at the workplace. In unit 1 (72 women), the intervention consisted of iddli four times a week plus information, education, and communication (IEC) related to iron-deficiency anemia. Unit 2 (80 women) received 20 ml of gooseberry juice (containing 40 mg of vitamin C) three times a week plus IEC once a month. Women in unit 3 (70 women), the positive control, received 400 mg albendazole once plus ferrous sulfate tablets (60 mg elemental iron) two times a week. No IEC was given. Unit 4 (70 women) served as the negative control and received no intervention. The pre-post impact measures were dietary and nutrient intake, knowledge and practice, and hemoglobin status. In units 1, 2, and 3, the hemoglobin status of the women improved significantly from 11.10 to 12.30 g/dl, 11.20 to 12.70 g/dl, and 11.50 to 13.00 g/dl, respectively. In unit 4 there was no change: the values were 10.90 g/dl before and after intervention. The results show that the type of workplace lunch was of greater significance than IEC. Knowledge gains were impressive, but behavioral change was not sustained. It was concluded that the hemoglobin levels of the workers can easily be improved by cost-effective workplace lunches that also lead to better employer-employee relations.  相似文献   
999.
OBJECTIVE: To determine state legislators' perceptions about health and tobacco lobbyists, their frequency of contact with these lobbyists, and the amount of campaign contributions from health professional organisations and the tobacco industry. DESIGN: Cross-sectional study. SUBJECTS: State legislators from North Carolina, Texas, and Vermont (USA), serving in 1994. MAIN OUTCOME MEASURES: Perceptions about lobbyists representing the tobacco industry, non-profit health organisations, and state medical societies with respect to their credibility, importance as sources of information, and persuasiveness; extent of lobbying activities; campaign contributions from health professional organisations and the tobacco industry. RESULTS: Almost all legislators reported that medical society and non-profit health organisation lobbyists are credible on tobacco issues and just over half believed that these lobbyists are important sources of information. More legislators said they could be persuaded by medical and health lobbyists than by tobacco lobbyists. Although health professional Political Action Committees (PACs) gave campaign contributions to more state legislators, and gave higher amounts on average, than tobacco PACs, legislators reported less contact with medical society lobbyists than tobacco lobbyists about tobacco issues. CONCLUSIONS: State legislators have positive attitudes toward lobbyists for non-profit health organisations and state medical societies regarding tobacco issues. These groups may be an underused resource for educating legislators about tobacco control measures.


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1000.
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