Intercomparisons of airborne measurements of aerosol ionic chemical composition during TRACE-P and ACE-Asia

As part of the two field studies, Transport and Chemical Evolution over the Pacific (TRACE-P) and the Asian Aerosol Characterization Experiment (ACE-Asia), the inorganic chemical composition of tropospheric aerosols was measured over the western Pacific from three separate aircraft using various methods. Comparisons are made between the rapid online techniques of the particle into liquid sampler (PILS) for measurement of a suite of fine particle a mist chamber/ion chromatograph (MC/IC) measurement of fine sulfate, and the longer time-integrated filter and micro-orifice impactor (MOI) measurements. Comparisons between identical PILS on two separate aircraft flying in formation showed that they were highly correlated (e.g., sulfate r2 of 0.95), but were systematically different by 10 ± 5% (linear regression slope and 95% confidence bounds), and had generally higher concentrations on the aircraft with a low-turbulence inlet and shorter inlet-to-instrument transmission tubing. Comparisons of PILS and mist chamber measurements of fine sulfate on two different aircraft during formation flying had an r 2 of 0.78 and a relative difference of 39% ± 5%. MOI ionic data integrated to the PILS upper measurement size of 1.3 mm sampling from separate inlets on the same aircraft showed that for sulfate, PILS and MOI were within 14% ± 6% and correlated with an r 2 of 0.87. Most ionic compounds were within ±30%, which is in the range of differences reported between PILS and integrated samplers from ground-based comparisons. In many cases, direct intercomparison between the various instruments is difficult due to differences in upper-size detection limits. However, for this study, the results suggest that the fine particle mass composition measured from aircraft agree to within 30–40%

Does perception equal reality? Weight misperception in relation to weight-related attitudes and behaviors among overweight and obese US adults

<p>Abstract</p> <p>Background</p> <p>Weight misperception might preclude the adoption of healthful weight-related attitudes and behaviors among overweight and obese individuals, yet limited research exists in this area. We examined associations between weight misperception and several weight-related attitudes and behaviors among a nationally representative sample of overweight and obese US adults.</p> <p>Methods</p> <p>Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used. Analyses included non-pregnant, overweight and obese (measured body mass index ≥ 25) adults aged 20 and older. Weight misperception was identified among those who reported themselves as "underweight" or "about the right weight". Outcome variables and sample sizes were: weight-loss attitudes/behaviors (wanting to weigh less and having tried to lose weight; n = 4,784); dietary intake (total energy intake; n = 4,894); and physical activity (meets 2008 US physical activity recommendations, insufficiently active, and sedentary; n = 5,401). Multivariable regression models were stratified by gender and race/ethnicity. Analyses were conducted in 2009-2010.</p> <p>Results</p> <p>These overweight/obese men and women who misperceived their weight were 71% (RR 0.29, 95% CI 0.25-0.34) and 65% (RR 0.35, 95% CI 0.29-0.42) less likely to report that they want to lose weight and 60% (RR 0.40, 95% CI 0.30-0.52) and 56% (RR 0.44, 95% CI 0.32-0.59) less likely to have tried to lose weight within the past year, respectively, compared to those who accurately perceived themselves as overweight. Blacks were particularly less likely to have tried to lose weight. Weight misperception was not a significant predictor of total energy intake among most subgroups, but was associated with lower total energy intake among Hispanic women (change -252.72, 95% CI -433.25, -72.18). Men who misperceived their weight were less likely (RR 0.68, 95% CI 0.52-0.89) to be insufficiently active (the strongest results were among Black men) and women who misperceived their weight were less likely (RR 0.74, 95% CI 0.54, 1.00, <it>p </it>= 0.047) to meet activity recommendations compared to being sedentary.</p> <p>Conclusion</p> <p>Overall, weight misperception among overweight and obese adults was associated with less likelihood of interest in or attempts at weight loss and less physical activity. These associations varied by gender and race/ethnicity. This study highlights the importance of focusing on inaccurate weight perceptions in targeted weight loss efforts.</p

Coulomb Gaps in One-Dimensional Spin-Polarized Electron Systems

We investigate the density of states (DOS) near the Fermi energy of one-dimensional spin-polarized electron systems in the quantum regime where the localization length is comparable to or larger than the inter-particle distance. The Wigner lattice gap of such a system, in the presence of weak disorder, can occur precisely at the Fermi energy, coinciding with the Coulomb gap in position. The interplay between the two is investigated by treating the long-range Coulomb interaction and the random disorder potential in a self-consistent Hartree-Fock approximation. The DOS near the Fermi energy is found to be well described by a power law whose exponent decreases with increasing disorder strength.Comment: 4 pages, revtex, 4 figures, to be published in Phys. Rev. B as a Rapid Communicatio

Interactions, Localization, and the Integer Quantum Hall Effect

We report on numerical studies of the influence of Coulomb interactions on localization of electronic wavefunctions in a strong magnetic field. Interactions are treated in the Hartree-Fock approximation. Localization properties are studied both by evaluating participation ratios of Hartree-Fock eigenfunctions and by studying the boundary-condition dependence of Hartree-Fock eigenvalues. We find that localization properties are independent of interactions. Typical energy level spacings near the Fermi level and the sensitivity of those energy levels to boundary condition show similar large enhancements so that the Thouless numbers of the Hartree-Fock eigenvalues are similar to those of non-interacting electrons.Comment: 10 pages, latex (revtex 3.0), 3 figures are avaiable from S.R. Eric Yang (e-mail [email protected]

Electromagnetic Wave Theory and Applications

Contains reports on eleven research projects.Joint Services Electronics Program (Contract DAAG29-83-K-0003)Joint Services Electronics Program (Contract DAAL03-86-K-0002)National Science Foundation (Grant ECS82-03390)National Science Foundation (Grant ECS85-04381)Schlumberger-Doll Research CenterNational Aeronautics and Space Administration (Contract NAG 5-141)National Aeronautics and Space Administration (Contract NAS 5-26861)National Aeronautics and Space Administration (Contract NAG 5-270)U.S. Navy - Office of Naval Research (Contract N00014-83-K-0258)National Aeronautics and Space Administration (Contract NAG 5-725)International Business Machines, Inc.Lincoln Laborator

Optical cooper pair breaking spectroscopy of cuprate superconductors

The photon energy dependence of the optical Cooper pair breaking rate (CPBR) is studied for compressibly strained La1.85Sr0.15CuO4 (LSCO) films and YBa2Cu2.92Zn0.08O7-&#948; (YBCZO) thin films, and compared to that in YBa2Cu3O7-&#948; (YBCO). Unlike YBCO, the CPBR for LSCO does not show an obvious photon energy dependence. In YBCZO, the CPBR shows a strong energy dependence similar to YBCO, but with a redshift in the peak position. Analysis of these results strongly favors a physical picture based on electronic phase separation in high-Tc superconductivity

JAM-A regulates permeability and inflammation in the intestine in vivo

Recent evidence has linked intestinal permeability to mucosal inflammation, but molecular studies are lacking. Candidate regulatory molecules localized within the tight junction (TJ) include Junctional Adhesion Molecule (JAM-A), which has been implicated in the regulation of barrier function and leukocyte migration. Thus, we analyzed the intestinal mucosa of JAM-A–deficient (JAM-A−/−) mice for evidence of enhanced permeability and inflammation. Colonic mucosa from JAM-A−/− mice had normal epithelial architecture but increased polymorphonuclear leukocyte infiltration and large lymphoid aggregates not seen in wild-type controls. Barrier function experiments revealed increased mucosal permeability, as indicated by enhanced dextran flux, and decreased transepithelial electrical resistance in JAM-A−/− mice. The in vivo observations were epithelial specific, because monolayers of JAM-A−/− epithelial cells also demonstrated increased permeability. Analyses of other TJ components revealed increased expression of claudin-10 and -15 in the colonic mucosa of JAM-A−/− mice and in JAM-A small interfering RNA–treated epithelial cells. Given the observed increase in colonic inflammation and permeability, we assessed the susceptibility of JAM-A−/− mice to the induction of colitis with dextran sulfate sodium (DSS). Although DSS-treated JAM-A−/− animals had increased clinical disease compared with controls, colonic mucosa showed less injury and increased epithelial proliferation. These findings demonstrate a complex role of JAM-A in intestinal homeostasis by regulating epithelial permeability, inflammation, and proliferation