305 research outputs found

    Ozone’s Impact on Public Health: Contributions from Indoor Exposures to Ozone and Products of Ozone-Initiated Chemistry

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    OBJECTIVE: The associations between ozone concentrations measured outdoors and both morbidity and mortality may be partially due to indoor exposures to ozone and ozone-initiated oxidation products. In this article I examine the contributions of such indoor exposures to overall ozone-related health effects by extensive review of the literature as well as further analyses of published data. FINDINGS: Daily inhalation intakes of indoor ozone (micrograms per day) are estimated to be between 25 and 60% of total daily ozone intake. This is especially noteworthy in light of recent work indicating little, if any, threshold for ozone’s impact on mortality. Additionally, the present study estimates that average daily indoor intakes of ozone oxidation products are roughly one-third to twice the indoor inhalation intake of ozone alone. Some of these oxidation products are known or suspected to adversely affect human health (e.g., formaldehyde, acrolein, hydroperoxides, fine and ultrafine particles). Indirect evidence supports connections between morbidity/mortality and exposures to indoor ozone and its oxidation products. For example, cities with stronger associations between outdoor ozone and mortality tend to have residences that are older and less likely to have central air conditioning, which implies greater transport of ozone from outdoors to indoors. CONCLUSIONS: Indoor exposures to ozone and its oxidation products can be reduced by filtering ozone from ventilation air and limiting the indoor use of products and materials whose emissions react with ozone. Such steps might be especially valuable in schools, hospitals, and childcare centers in regions that routinely experience elevated outdoor ozone concentrations

    Exhaled nitric oxide in a population-based study of Southern California Schoolchildren

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    <p>Abstract</p> <p>Background</p> <p>Determinants of exhaled nitric oxide (FeNO) need to be understood better to maximize the value of FeNO measurement in clinical practice and research. Our aim was to identify significant predictors of FeNO in an initial cross-sectional survey of southern California schoolchildren, part of a larger longitudinal study of asthma incidence.</p> <p>Methods</p> <p>During one school year, we measured FeNO at 100 ml/sec flow, using a validated offline technique, in 2568 children of age 7–10 yr. We estimated online (50 ml/sec flow) FeNO using a prediction equation from a separate smaller study with adjustment for offline measurement artifacts, and analyzed its relationship to clinical and demographic characteristics.</p> <p>Results</p> <p>FeNO was lognormally distributed with geometric means ranging from 11 ppb in children without atopy or asthma to 16 ppb in children with allergic asthma. Although effects of atopy and asthma were highly significant, ranges of FeNO for children with and without those conditions overlapped substantially. FeNO was significantly higher in subjects aged > 9, compared to younger subjects. Asian-American boys showed significantly higher FeNO than children of all other sex/ethnic groups; Hispanics and African-Americans of both sexes averaged slightly higher than non-Hispanic whites. Increasing height-for-age had no significant effect, but increasing weight-for-height was associated with decreasing FeNO.</p> <p>Conclusion</p> <p>FeNO measured offline is a useful biomarker for airway inflammation in large population-based studies. Further investigation of age, ethnicity, body-size, and genetic influences is needed, since they may contribute to substantial variation in FeNO.</p

    Pulmonary function testing in quadriplegic subjects

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    Study design: Cross-sectional study.Objective: Pulmonary functional capacity in 23 Brazilian quadriplegic subjects (ASIA A), aged 30 (9.5) years, weight 66 (10.75) kg, height 176 (7) cm, was investigated at 42 ( 64) months postinjury.Setting: University Hospital-UNICAMP, Campinas, Brazil.Method: Subjects performed forced vital capacity ( FVC) and maximal voluntary ventilation (MVV) tests while seated in their standard wheelchairs. Forced Expired Volume after 1 s (FEV1) and FVC/FEV1 ratio were calculated from these tests. Values obtained were compared to three prediction equations from the literature that are used specifically for spinal cord subjects and include different variables in their formulae, such as age, gender, height, postinjury time and injury level. Data are expressed as median (interquartile interval). Differences between values were demonstrated by median confidence interval with significance level set at a 0.05.Results: Obtained data were statistically different from prediction equation results, with FVC 3.11 ( 0.81), 4.46 (0.28), 4.16 (0.33), 4.26 (0.42); FEV1 2.77 (1.03), 3.67 (0.21), 3.66 (0.30), 3.45 (0.39) and MVV 92 (27), 154.2 (11.9), 156.6 (14),157.3 (16.8), where the first value is obtained experimentally and the second, third and fourth values correspond to predicted values. the results obtained from spirometry test in this study differed significantly from the results obtained when prediction equations were used.Conclusion: the use of prediction equations developed to estimate pulmonary function in wheelchair users significantly overestimates pulmonary function of quadriplegic individuals with complete lesions (ASIA group A), in comparison to measured values.Univ Estadual Campinas, Dept Orthopedia & Traumatol, FCM, BR-13083970 Campinas, SP, BrazilUniv Estadual Campinas, Fac Phys Educ, BR-13083970 Campinas, SP, BrazilUniversidade Federal de SĂŁo Paulo, Santos, SP, BrazilUniv SĂŁo Paulo, Fac Med, Dept Biomech Med & Rehabil Locomotor Syst, BR-14049 Ribeirao Preto, BrazilUniv SĂŁo Paulo, Dept Elect Engn, Sao Carlos, SP, BrazilUniversidade Federal de SĂŁo Paulo, Santos, SP, BrazilWeb of Scienc

    Attractiveness of a Four-component Pheromone Blend to Male Navel Orangeworm Moths

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    The attractiveness to male navel orangeworm moth, Amyelois transitella, of various combinations of a four-component pheromone blend was measured in wind-tunnel bioassays. Upwind flight along the pheromone plume and landing on the odor source required the simultaneous presence of two components, (11Z,13Z)-hexadecadienal and (3Z,6Z,9Z,12Z,15Z)-tricosapentaene, and the addition of either (11Z,13Z)-hexadecadien-1-ol or (11Z,13E)-hexadecadien-1-ol. A mixture of all four components produced the highest levels of rapid source location and source contact. In wind-tunnel assays, males did not seem to distinguish among a wide range of ratios of any of the three components added to (11Z,13Z)-hexadecadienal. Dosages of 10 and 100 ng of the 4-component blend produced higher levels of source location than dosages of 1 and 1,000 ng

    Virtual Blocks: a serious game for spatial ability improvement on mobile devices

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    This paper presents a novel spatial instruction system for improving spatial abilities of engineering students. A 3D mobile game application called Virtual Blocks has been designed to provide a 3D virtual environment to build models with cubes that help students to perform visualization tasks to promote the development of their spatial ability during a short remedial course. A validation study with 26 freshman engineering students at La Laguna University (Spain) has concluded that the training had a measurable and positive impact on students spatial ability. In addition, the results obtained using a satisfaction questionnaire show that Virtual Blocks is considered an easy to use and stimulating application.This work has been partially supported by the (Spanish) National Program for Studies and Analysis project "Evaluation and development of competencies associated to the spatial ability in the new engineering undergraduate courses" (Ref. EA2009-0025) and the (Spanish) National Science Project "Enhancing Spatial REasoning and VIsual Cognition with advanced technological tools (ESREVIC)" (Ref TIN2010-21296-C02-02)Martín Dorta, NN.; Sanchez Berriel, I.; Bravo, M.; Hernández, J.; Saorin, JL.; Contero, M. (2014). Virtual Blocks: a serious game for spatial ability improvement on mobile devices. Multimedia Tools and Applications. 73(3):1575-1595. https://doi.org/10.1007/s11042-013-1652-0S15751595733Baartmans BG, Sorby SA (1996) Introduction to 3-D spatial visualization. Prentice Hall, Englewood CliffsClements D, Battista M (1992) Geometry and spatial reasoning. In: Grouws DA (ed) Handbook of research on mathematics teaching and learning. New York, pp 420–464Cohen J (1988) Statistical power analysis for the behavioral sciences, 2nd edn. Erlbaum, HillsdaleDe Lisi R, Cammarano DM (1996) Computer experience and gender differences in undergraduate mental rotation performance. Comput Hum Behav 12:351–361Deno JA (1995) The relationship of previous experiences to spatial visualization ability. Eng Des Graph J 59(3):5–17Feng J, Spence I, Pratt J (2007) Playing an action video game reduces gender differences in spatial cognition. Psychol Sci 18(10):850–855French JW (1951) The description of aptitude and achievement tests in terms of rotated factors. Psychometric monograph 5Guilford JP, Lacy JI (1947) Printed classification tests, A.A.F. Aviation Psychological Progress Research Report, 5. US. Government Printing Office, Washington DCHalpern DF (2000) Sex differences and cognitive abilities. Erlbaum, MahwahHöfele C (2007) Mobile 3D graphics: learning 3D graphics with the Java Micro Edition. Editorial ThomsonKajiya JT, Kay TL (1989) Rendering fur with three dimensional textures. In Proceedings of the 16th Annual Conference on Computer Graphics and interactive Techniques SIGGRAPH ’89. ACM Press, New York pp 271–280Linn MC, Petersen AC (1985) Emergence and characterization of gender differences in spatial abilities: a meta-analysis. Child Dev 56:1479–1498Martin-Dorta N, Sanchez-Berriel I, Bravo M, Hernandez J, Saorin JL, Contero M (2010) A 3D educational mobile game to enhance student’s spatial skills, ICALT, pp.6–10, 2010 10th IEEE International Conference on Advanced Learning TechnologiesMartin-Dorta N, Saorin J, Contero M (2008) Development of a fast remedial course to improve the spatial abilities of engineering students. J Eng Educ 27(4):505–514Martin-Dorta N, Saorin JL, Contero M (2011) Web-based spatial training using handheld touch screen devices. Educ Technol Soc 14(3):163–177McGee MG (1979) Human spatial abilities: psychometric studies and environmental, genetic, hormonal, and neurological influences. Psychol Bull 86:889–918Noguera JM, Segura RJ, Ogayar CJ, Joan-Arinyo R (2011) Navigating large terrains using commodity mobile devices. Comput Geosci 37:1218–1233Okagaki L, Frensch PA (1994) Effects of video game playing on measures of spatial performance: gender effects in late adolescence. J Appl Dev Psychol 15(1):33–58Pulli K, Aarnio T, Miettinen V, Roimela K, Vaarala J (2007) Mobile 3D graphics with OpenGL ES and M3G. Editorial Morgan KaufmannQuaiser-Pohl C, Geiser C, Lehmann W (2005) The relationship between computer-game preference, gender, and mental-rotation ability. Personal Individ Differ 40(3):609–619Smith IM (1964) Spatial ability- its educational and social significance. The University of London Press, LondonSorby S (2007) Developing 3D spatial skills for engineering students. Australas Assoc Eng Educ 13(1):1–11Terlecki MS, Newcombe NS (2005) How important is the digital divide? The relation of computer and videogame usage to gender differences in mental rotation ability. Sex Roles 53(5/6):433–441Terlecki MS, Newcombe NS, Little M (2008) Durable and generalized effects of spatial experience on mental rotation: gender differences in growth patterns. Appl Cogn Psychol 22:996–1013Thurstone LL (1950) Some primary abilities in visual thinking (Tech. Rep. No. 59). IL University of Chicago Psychometric Laboratory, ChicagoThurstone LL, Thurstone TG (1941) Factorial studies of intelligence. Psychometric monographs. Chicago Press, ChicagoVanderberg S, Kuse A (1978) Mental Rotation, a group test of three dimensional spatial visualization. Percept Mot Skills 47:599–604Zimmerman WS (1954) Hypotheses concerning the nature of the spatial factors. Educ Psychol Meas 14:396–40

    Is there adaptation in the ozone mortality relationship: A multi-city case-crossover analysis

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    <p>Abstract</p> <p>Background</p> <p>Ozone has been associated with daily mortality, mainly in the summer period. Despite the ample literature on adaptation of inflammatory and pulmonary responses to ozone, and the link, in cohort studies, between lung function and mortality risk there has been little done to date to examine the question of adaptation in the acute mortality risk associated with ambient ozone.</p> <p>Methods</p> <p>We applied a case-crossover design in 48 US cities to examine the ozone effect by season, by month and by age groups, particularly focusing on whether there was an adaptation effect.</p> <p>Results</p> <p>We found that the same day ozone effect was highest in summer with a 0.5% (95% CI: 0.38, 0.62) increase in total mortality for 10 ppb increase in 8-hr ozone, whilst the effect decrease to null in autumn and winter. We found higher effects in the months May- July with a 0.46% (95% CI: 0.24, 0.68) increase in total mortality for 10 ppb increase in ozone in June, and a 0.65% (95% CI: 0.47, 0.82) increase in mortality during July. The effect decreased in August and became null in September. We found similar effects from the age group 51–60 up to age 80 and a lower effect in 80 years and older.</p> <p>Conclusion</p> <p>The mortality effects of ozone appear diminished later in the ozone season, reaching the null effect previously reported in winter by September. More work should address this issue and examine the biological mechanism of adaptation.</p

    Mutual Information for Testing Gene-Environment Interaction

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    Despite current enthusiasm for investigation of gene-gene interactions and gene-environment interactions, the essential issue of how to define and detect gene-environment interactions remains unresolved. In this report, we define gene-environment interactions as a stochastic dependence in the context of the effects of the genetic and environmental risk factors on the cause of phenotypic variation among individuals. We use mutual information that is widely used in communication and complex system analysis to measure gene-environment interactions. We investigate how gene-environment interactions generate the large difference in the information measure of gene-environment interactions between the general population and a diseased population, which motives us to develop mutual information-based statistics for testing gene-environment interactions. We validated the null distribution and calculated the type 1 error rates for the mutual information-based statistics to test gene-environment interactions using extensive simulation studies. We found that the new test statistics were more powerful than the traditional logistic regression under several disease models. Finally, in order to further evaluate the performance of our new method, we applied the mutual information-based statistics to three real examples. Our results showed that P-values for the mutual information-based statistics were much smaller than that obtained by other approaches including logistic regression models

    Estimation of Short-Term Effects of Air Pollution on Stroke Hospital Admissions in Wuhan, China

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    Background and Objective:High concentrations of air pollutants have been linked to increased incidence of stroke in North America and Europe but not yet assessed in mainland China. The aim of this study is to evaluate the association between stroke hospitalization and short-term elevation of air pollutants in Wuhan, China.Methods:Daily mean NO2, SO2 and PM10 levels, temperature and humidity were obtained from 2006 through 2008. Data on stroke hospitalizations (ICD 10: I60-I69) at four hospitals in Wuhan were obtained for the same period. A time-stratified case-crossover design was performed by season (April-September and October-March) to assess effects of pollutants on stroke hospital admissions.Results:Pollution levels were higher in October-March with averages of 136.1 Οg/m3 for PM10, 63.6 Οg/m3 for NO2 and 71.0 Οg/m3 for SO2 than in April-September when averages were 102.0 Οg/m3, 41.7 Οg/m3 and 41.7 Οg/m3, respectively (p<.001). During the cold season, every 10 Οg/m3 increase in NO2 was associated with a 2.9% (95%C.I. 1.2%-4.6%) increase in stroke admissions on the same day. Every 10 ug/m3 increase in PM10 daily concentration was significantly associated with an approximate 1% (95% C.I. 0.1%-1.4%) increase in stroke hospitalization. A two-pollutant model indicated that NO2 was associated with stroke admissions when controlling for PM10. During the warm season, no significant associations were noted for any of the pollutants.Conclusions:Exposure to NO2 is significantly associated with stroke hospitalizations during the cold season in Wuhan, China when pollution levels are 50% greater than in the warm season. Larger and multi-center studies in Chinese cities are warranted to validate our findings. Š 2013 Xiang et al

    X-ray emission from the Sombrero galaxy: discrete sources

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    We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres
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