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Landmark, MA, United States

Halonen J.I.,Harvard University | Halonen J.I.,University of Eastern Finland | Halonen J.I.,Landmark Center West | Zanobetti A.,Harvard University | And 5 more authors.
Environmental Health: A Global Access Science Source | Year: 2010

Background: Associations between ambient temperature and cardiovascular mortality are well established. This study investigated whether inflammation could be part of the mechanism leading to temperature-related cardiovascular deaths. Methods: The study population consisted of a cohort of 673 men with mean age of 74.6 years, living in the greater Boston area. They were seen for examination roughly every 4 years, and blood samples for inflammation marker analyses were drawn in 2000-2008 (total of 1254 visits). We used a mixed effects model to estimate the associations between ambient temperature and a variety of inflammation markers (C-reactive protein, white blood cell count, soluble Vascular Cell Adhesion Molecule-1, soluble Intercellular Adhesion Molecule-1, tumor necrosis factor alpha, and interleukins -1β, -6 and -8). Random intercept for each subject and several possible confounders, including combustion-related air pollution and ozone, were used in the models. Results: We found a 0 to 1 day lagged and up to 4 weeks cumulative responses in C-reactive protein in association with temperature. We observed a 24.9% increase [95% Confidence interval (CI): 7.36, 45.2] in C-reactive protein for a 5°C decrease in the 4 weeks' moving average of temperature. We observed similar associations also between temperature and soluble Intercellular Adhesion Molecule-1 (4.52%, 95% CI: 1.05, 8.10, over 4 weeks' moving average), and between temperature and soluble Vascular Cell Adhesion Molecule-1 (6.60%, 95% CI: 1.31, 12.2 over 4 weeks' moving average). Penalized spline models showed no deviation from linearity. There were no associations between temperature and other inflammation markers. Conclusions: Cumulative exposure to decreased temperature is associated with an increase in inflammation marker levels among elderly men. This suggests that inflammation markers are part of intermediate processes, which may lead to cold-, but not heat-, related cardiovascular deaths. © 2010 Halonen et al; licensee BioMed Central Ltd.

Son Y.-S.,Landmark Center West | Kim J.,Konkuk University | Kim J.-C.,Konkuk University
Plasma Chemistry and Plasma Processing | Year: 2014

This study investigated the decomposition characteristics of acetaldehyde using an electron beam. The removal efficiency (RE) in air, O2, N2 and He atmospheres at 10 kGy were 88, 89, 94 and 35 %, respectively. By varying the initial concentration (C0), G-values at 240 ppm (C0) were maintained from 6.4 to 7.0 molecules/100 eV, while the G-values at 34 and 60 ppm (C0) decreased from 4.5 to 1.1 and from 6.6 to 2.0 molecules/100 eV when the absorbed dose increased from 2.5 to 10 kGy. The RE of acetaldehyde at 96 % relative humidity was approximately 10-15 % higher than that at dry air when the absorbed doses were 5-10 kGy. Increasing the water supply did not provide additional improvement of the RE at 2.5 kGy. CO, CO2, O3 and trace VOC compounds such as C 2H4O2, C7H6O, C 6H6, C7H8 and C8H 10 were detected as by-products. © 2014 Springer Science+Business Media New York.

Papapostolou V.,Harvard University | Papapostolou V.,Landmark Center West | Lawrence J.E.,Harvard University | Ferguson S.T.,Harvard University | And 4 more authors.
Air Quality, Atmosphere and Health | Year: 2013

Atmospheric photochemical reactions of vehicular primary emissions result in the formation of secondary organic aerosol (SOA). This is the first study that has investigated the toxicity of secondary particles based on fleet vehicular emissions. We developed methods for photochemical oxidation of traffic primary emissions to produce mixtures of primary and/or secondary particles suitable for animal exposures. The exposure generation system produced test atmospheres of primary (P), aged primary plus SOA (P + SOA), or SOA particles suitable for animal exposures. The system consists of (1) a sampling system to extract the traffic emissions from the plenum of a highway tunnel ventilation stack, (2) a photochemical chamber to simulate atmospheric aging, and (3) a nonselective diffusion denuder to remove gaseous pollutants prior to exposure. In the presence of traffic primary particles (P + SOA), a longer mean residence time resulted in a higher SOA yield. Higher baseline plenum primary particle mass concentration resulted in lower SOA yield. In the absence of primary particles (SOA), higher plenum gas concentrations resulted in higher SOA yield. Secondary aerosol was largely organic but contained some nitrate and sulfate. Formation of secondary aerosol is influenced significantly by reaction of primary gases with ·OH. The system (1) provides adequate flow and stable chamber output of P, P + SOA, and SOA for characterization and animal exposures and (2) generates reproducible exposure atmospheres of P, P + SOA, and SOA, all at consistent mass concentrations. © 2012 Springer Science+Business Media B.V.

Alcantara C.,Landmark Center West | Abelson J.L.,University of Michigan | Gone J.P.,University of Michigan
Depression and Anxiety | Year: 2012

Background Nervios (PNRV) and ataque de nervios (ATQ) are culture-bound syndromes with overlapping symptoms of anxiety, depression, and dissociation, shown to have inconsistent associations to psychiatric disorder. Few studies test the basic assumption that PNRV and ATQ are uniformly linked to distress outcomes across Latina/o immigrant groups. This study examined: (a) the extent to which acculturative stress, Latino/US American acculturation, and anxious predisposition were associated with lifetime history of ATQ and PNRV, and (b) the extent to which ATQ and PNRV add incremental validity in explaining acculturative stress and psychological distress beyond measures of anxious predisposition. Method Participants (n = 82) included Mexican mothers who completed surveys on acculturation, trait anxiety, anxiety sensitivity, lifetime ATQ/PNRV, psychological distress, and acculturative stress. Results Lifetime PNRV, but not lifetime ATQ, was significantly predictive of psychological distress. PNRV was also linked to trait anxiety. Psychometric measures of anxious predisposition (trait anxiety and anxiety sensitivity) were more robust predictors of distress outcomes than lifetime history of ATQ/PNRV. Conclusion Inquiry into lifetime history of nervios may be a useful point of entry in talking to Mexican immigrant mothers about stress and distress. However, standard tools for assessing anxiety sensitivity and trait anxiety appear most useful in identifying and explaining the presence of psychological distress. Further research is needed to determine the cross-cultural relevance of trait anxiety and anxiety sensitivity, and its implications for the development of anxiety treatments that are effective across cultures. Depression and Anxiety 0:1-9, 2011. © 2011 Wiley-Liss, Inc.

Lee W.-C.,Landmark Center West | Catalano P.J.,Dana-Farber Cancer Institute | Yoo J.Y.,Seoul National University | Park C.J.,Seoul National University | Koutrakis P.,Landmark Center West
Environmental Science and Technology | Year: 2015

We validated the use of the mass balance model to determine the effectiveness of portable air purifiers in removing ultrafine (<0.10 μm) and submicrometer particles (0.10-0.53 μm) in an apartment. We evaluated two identical portable air purifiers, equipped with high efficiency particulate air filters, for their performance under three different air flow settings and three target air exchange rates: 0.60, 0.90, and 1.20 h-1. We subsequently used a mixed effects model to estimate the slope between the measured and modeled effectiveness by particle size. Our study showed that effectiveness was highly particle size-dependent. For example, at the lowest target air exchange rate, it ranged from 0.33 to 0.56, 0.51 to 0.75, and 0.60 to 0.81 for the three air purifier flow settings, respectively. Our findings suggested that filtration was the dominant removal mechanism for submicrometer particles, whereas deposition could play a more important role in ultrafine particle removal. We found reasonable agreement between measured and modeled effectiveness with size-resolved slopes ranging from 1.11 ± 0.06 to 1.25 ± 0.07 (mean ± SE), except for particles <35 nm. Our study design can be applied to investigate the performances of other portable air purifiers as well as the influences of various parameters on effectiveness in different residential settings. © 2015 American Chemical Society.

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