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991.
Sullivan Karen A.; White Katherine M.; Young Ross McD.; Chang Anne; Roos Colette; Scott Clinton 《Canadian Metallurgical Quarterly》2008,53(4):505
Purpose: To examine predictors of intention to reduce stroke risk in a sample of at risk individuals through the application of an expanded Health Belief Model. Research Method: Predictors included stroke knowledge, demographic variables, beliefs about stroke, and measures of subjective norm and self-efficacy. The dependent variable was intention to reduce stroke risk. Of the 276 surveys distributed to bowling clubs, senior citizens clubs or retirement villages, 101 surveys were returned. Data from 76 of these respondents were used for analysis. Results: With regard to exercise intention, a pattern of significant correlations between HBM variables, subjective norm, and self-efficacy was observed. Results of multiple hierarchical regression analyses showed that perceived benefits of undertaking exercise and self-efficacy in relation exercise were the two most important determinants of exercise intentions. Conclusions: Findings suggest that health beliefs may play an important role in stroke prevention. Practice Implications: Stroke education and prevention programs that selectively target beliefs about the perceived benefits of, and self-efficacy related to, exercise to reduce stroke risk may prove most efficacious. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Karen Stoeffler Pierre G. Lafleur Johanne Denault 《Polymer Engineering and Science》2008,48(8):1449-1466
Alkyl pyridinium, 1‐vinyl alkyl imidazolium, 1,3‐dialkyl imidazolium, and tetraalkyl phosphonium bromides were successfully used as intercalants for the preparation of highly thermally stable organophilic montmorillonites. Nanocomposites of linear low density polyethylene (LLDPE) and linear low density polyethylene grafted with maleic anhydride (LLDPE/LLDPE‐g‐MAH) were prepared from those organoclays. The micro‐ and nano‐dispersions were analyzed through X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM): intercalation and/or partial exfoliation were found to occur only for formulations based on organoclays having an initial basal distance higher than 20 Å, suggesting the existence of a critical interfoliar distance for the delamination of silicate layers in a noninteracting polymer matrix. The properties of the nanocomposites were analyzed through differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and oscillatory rheometry. The dynamic crystallization of LLDPE was not significantly affected by the presence of clay. TGA in oxidative atmosphere proved to be very sensitive to the dispersion state of the organoclay: the thermal stability was drastically enhanced for intercalated and partially exfoliated formulations. However, the inherent thermal stability of the organoclay did not appear to influence significantly the overall thermal stability of the composite in the range of temperatures investigated (160–230°C). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers. 相似文献
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Risovic V Rosland M Sivak O Wasan KM Bartlett K 《Drug development and industrial pharmacy》2007,33(7):703-707
The purpose of this study was to assess the antifungal activity of a new oral amphotericin B (AmpB) lipid-based formulation following administration to rats infected with Aspergillus fumigatus. Aspergillus fumigatus inoculum (2.1-2.5 × 107 colony forming units [CFU]) were injected via the jugular vein; 48h later male albino Sprague-Dawley rats (350-400 g) were administered either a single oral dose of AmpB incorporated into Peceol (50 mg AmpB/kg), physiologic saline (nontreated controls) or Peceol alone (vehicle control) once daily for 4 days. To assess antifungal activity Brain, Lung, Heart, Liver, Spleen and Kidney sections were homogenized with normal saline (1 mL/g of tissue) and a 0.1-mL aliquot was spread plated onto a Sabourand dextrose agar plate. The plates were incubated for 48 hr at 37°C, at which time the number of fungal CFU were determined and corrected for tissue weight. In addition, plasma galactomannan antigen concentrations were determined. Data was reported as mean ± standard error of the mean. The AmpB-Peceol oral formulation significantly decreased total fungal CFU concentrations recovered in all the organs added together, brain CFU concentrations, spleen CFU concentrations and plasma galactomannan antigen concentrations compared to baseline. No significant differences in lung, heart, liver and kidney CFU concentrations between treatment and control groups were observed. Peceol vehicle control did not exhibit any antifungal activity. These findings suggest that a new oral lipid-based formulation of AmpB incorporated into Peceol can significantly decrease brain and spleen CFU concentrations and plasma galactomannan antigen concentrations compared to non-treated controls. 相似文献
996.
A catalytic reactor for the trapping of free radicals originating from gas phase catalytic reactions is described and discussed. Radical trapping and identification were initially carried out using a known radical generator such as dicumyl peroxide. The trapping of radicals was further demonstrated by investigating genuine radical oxidation processes, e.g., benzaldehyde oxidation over manganese and cobalt salts. The efficiency of the reactor was finally proven by the partial oxidation of cyclohexane over MoO(3), Cr(2)O(3), and WO(3), which allowed the identification of all the radical intermediates responsible for the formation of the products cyclohexanol and cyclohexanone. Assignment of the trapped radicals was carried out using spin trapping technique and X-band electron paramagnetic resonance spectroscopy. 相似文献
997.
On February 27, 2011, a fire began in the outskirts of Amarillo, Texas, that destroyed or damaged buildings in three housing developments. The National Institute of Standards and Technology (NIST), as part of its Disaster and Failure Studies Program, deployed a team within 44 h of ignition to conduct an initial reconnaissance to document the fire event losses and fire behavior. The deployment was conducted jointly with the Texas Forest Service. Of interest to the NIST deployment was the fire behavior and effects on fire losses of topographical features, structure construction and defensive actions. The two communities initially evaluated were the Willow Creek South Complex and the Tanglewood Complex. Within 72 h after data collection initiation, the Tanglewood fire became the focus of the deployment. Additionally, destroyed and damaged structure data were collected to support the local and state damage assessment efforts. The Tanglewood Complex wildland-urban interface fire was responsible for the destruction of approximately 101 structures including 35 residences. The overall objectives of this study are to establish the likely technical factor or factors responsible for the damage, failure, and/or successful performance of buildings and/or infrastructure in the aftermath of the fire, and to recommend, as necessary, specific improvements to standards, codes, and practices based on study findings. This study also may be used to define areas of future research. This summary paper addresses the particulars of the deployment and the data collection methodology used. A second more detailed technical paper will provide the event timeline reconstruction and general fire behavior observations as well as investigate the impacts of structure attributes, landscaping characteristics, topographical features and wildland fire exposure on structure survivability. 相似文献
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999.
Carolien Beckx Luc Int Panis Karen Van De Vel Wouter Lefebvre Geert Wets 《The Science of the total environment》2009,407(12):3814-3822
The potential advantages of using activity-based transport models for air quality purposes have been recognized for a long time but models that have been developed along these lines are still scarce. In this paper we demonstrate that an activity-based model provides useful information for predicting hourly ambient pollutant concentrations. For this purpose, the traffic emissions obtained in a previous application of the activity-based model ALBATROSS were used as input for the AURORA air quality model to predict hourly concentrations of NO2, PM10 and O3 in the Netherlands. Predicted concentrations were compared with measured concentrations at 37 monitoring stations from the Dutch air quality monitoring network. A statistical analysis was performed to evaluate model performance for different pollutants, locations and time periods. Results confirm that modelled and measured concentrations present the same geographical and temporal variation. The overall index of agreement for the prediction of hourly pollutant concentrations amounted to 0.64, 0.75 and 0.57 for NO2, O3 and PM10 respectively. Concerning the predictions for NO2, a major traffic pollutant, a more thorough analysis revealed that the ALBATROSS-AURORA model chain yielded better predictions near traffic locations than near background stations. Further, the model performed better in urban areas, on weekdays and during the day, consistent with the emission results obtained in a previous study. The results in this paper demonstrate the ability of the activity-based model to predict the contribution of traffic sources to local air pollution with sufficient accuracy and confirms the usefulness of activity-based transport models for air quality purposes. The fact that the ALBATROSS-AURORA chain provides reliable pollutant concentrations on hourly basis for the whole Netherlands instead of using only daily averages near traffic stations is a plus for future exposure studies aiming at more realistic exposure analyses and health impact assessments. 相似文献
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