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101.
102.
Area 22-h average carbon monoxide (CO), total suspended particulates (TSP), particles less than 10 microns in diameter (PM10), and particles less than 2.5 microns in diameter (PM2.5) measurements were made in three test homes of highland rural Guatemala in kitchens, bedrooms, and outdoors on a longitudinal basis, i.e. before and after introduction of potential exposure-reducing interventions. Four cookstove conditions were studied sequentially: background (no stove in use); traditional open woodstove, improved woodstove with flue (plancha), and bottled-gas (LPG) stove. With nine observations each, kitchen PM2.5 levels were 56 micrograms/m3 under background conditions, 528 micrograms/m3 for open fire conditions, 96 micrograms/m3 for plancha conditions, and 57 micrograms/m3 for gas stove conditions. Corresponding PM10/TSP levels were 173/174, 717/836, 210/276, 186/218 micrograms/m3. Corresponding CO levels were 0.2, 5.9, 1.4, 1.2 ppm. Comparisons with other studies in the area indicate that the reductions in indoor concentrations achieved by improved wood-burning stoves deteriorate with stove age. Mother and child personal CO and PM2.5 measurements for each stove condition demonstrate the same trend as area measurements, but with less differentiation. 相似文献
103.
Indoor climate of two new blocks of flats was investigated. The case building was built for people with respiratory diseases by following the instructions of the Finnish Classification of Indoor Climate, Construction and Finishing Materials, while the control building was built using conventional building technology. The main indoor air parameters (temperature, relative humidity and levels of CO, CO2, ammonia, total volatile organic compounds, total suspended particles, fungal spores, bacteria and cat, dog and house dust mite allergens) were measured in six apartments of both the buildings on five occasions during the 3-year occupancy. In addition, a questionnaire to evaluate symptoms of the occupants and their satisfaction with their home environment was conducted in connection with indoor air quality (IAQ) measurements. The levels of indoor air pollutants in the case building were, in general, lower than those in the control building. In addition, the asthmatic occupants informed that their symptoms had decreased during the occupancy in the case building. This case study showed that high IAQ is possible to reach by careful design, proper materials and equipment and on high-quality construction with reasonable additional costs. In addition, the study indicated that good IAQ can also be maintained during the occupancy, if sufficient information on factors affecting IAQ and guidance on proper use and care of equipment are available for occupants. 相似文献
104.
Walters Glenn D.; Rogers Richard; Berry David T. R.; Miller Holly A.; Duncan Scott A.; McCusker Paul J.; Payne Joshua W.; Granacher Robert P. Jr. 《Canadian Metallurgical Quarterly》2008,20(3):238
The 6 nonoverlapping primary scales of the Structured Interview of Reported Symptoms (SIRS) were subjected to taxometric analysis in a group of 1,211 criminal and civil examinees in order to investigate the latent structure of feigned psychopathology. Both taxometric procedures used in this study, mean above minus below a cut (MAMBAC) and maximum covariance (MAXCOV), produced dimensional results. A subgroup of participants (n = 711) with valid Minnesota Multiphasic Personality Inventory-2 (MMPI-2) protocols were included in a second round of analyses in which the 6 nonoverlapping primary scales of the SIRS and the Infrequency (F), Infrequency-Psychopathology (Fp), and Dissimulation (Ds) scales of the MMPI-2 served as indicators. Again, the results were more consistent with dimensional latent structure than with taxonic latent structure. On the basis of these findings, it is concluded that feigned psychopathology forms a dimension (levels of fabrication or exaggeration) rather than a taxon (malingering-honest dichotomy) and that malingering is a quantitative distinction rather than a qualitative one. The theoretical and clinical practice implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Douwes J 《Indoor air》2005,15(3):160-169
(1-->3)-Beta-D-glucan are non-allergenic structural cell wall components of most fungi that have been suggested to play a causal role in the development of respiratory symptoms associated with indoor fungal exposure. This review describes the currently available epidemiological literature on health effects of (1-->3)-beta-D-glucan, focusing on atopy, airway inflammation and symptoms, asthma, and lung function. In addition to population studies, studies in human volunteers experimentally exposed to (1-->3)-beta-D-glucan are described as well as relevant animal studies. Furthermore, the review discusses exposure assessment methods, the potential for exposure control and it concludes with identifying research needs. The observational and experimental studies reviewed suggested some association between (1-->3)-beta-D-glucan exposure, airway inflammation and symptoms, however, results were mixed and specific symptoms and potential underlying inflammatory mechanisms associated with exposure could not be identified. Large observational studies using well validated exposure assessment methods are needed to further our knowledge regarding the potential health effects of indoor (1-->3)-beta-D-glucan exposure. PRACTICAL IMPLICATIONS: The currently available epidemiological data do not permit conclusions to be drawn regarding the presence (or absence) of an association between environmental (1-->3)-beta-D-glucan exposure and specific adverse health effects, nor is it clear from the currently available evidence which specific immunological mechanisms underlie the presumed health effects. More and larger observational studies are needed to asses whether (1-->3)-beta-D-glucan exposure plays a significant role in respiratory morbidity. In addition, existing methods to assess environmental (1-->3)-beta-D-glucan exposure require validation and further development before they can be used routinely in large scale epidemiological studies. 相似文献
106.
107.
Always Connected or Always Distracted? ADHD Symptoms and Social Assurance Explain Problematic Use of Mobile Phone and Multicommunicating
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Multicommunicating via mobile phone during face‐to‐face encounters with family and friends was examined with data from an online survey of 432 adults in the US. Multicommunicating was positively associated with problematic mobile phone use and explained by attention deficit/hyperactivity disorder (ADHD) symptoms and a social need to belong. Those with ADHD symptoms were more likely to engage in problematic mobile phone use and frequent multicommunicating. Strong need for social assurance, which involves an “always‐on‐and‐connected” lifestyle through mobile devices, explained problematic mobile phone use and multicommunicating. Need for social assurance also was related to multicommunicating via social connectedness, and this effect was significant among females, but not males. The implications of these findings for future research are discussed. 相似文献
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109.
This study evaluated locomotory and respiratory responses induced by ozone at a concentration of 500 ppm in five Brazilian populations of Rhyzopertha dominica (Coleoptera: Bostrichidae). Toxicity and body mass were also assessed to establish their relationship with behavioral patterns. The results indicated that none of the evaluated populations of Rhyzopertha dominica showed resistance to ozone. No significant correlations were observed between ozone toxicity and locomotory behavioral patterns. Moreover, no significant correlations were found between ozone toxicity and the respiratory rate of Rhyzopertha dominica. Ozone is a potential alternative for phosphine resistance management, and its rapid degradation constitutes an advantage for the environment. 相似文献
110.
The paper describes studies towards developing lubricant additive technology to improve the fatigue performance of an oil. The extraordinary performance of a particular organic phosphonate antifatigue additive observed in the authors' laboratory and elsewhere is reviewed together with conflicting EHD film thickness studies of this additive reported in the literature. New optical EHD measurements and electron microscope and microprobe studies which define the mechanism by which the additive acts, are presented. 相似文献