bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing and Testing the CHORDS: Characteristics of Responsible Drinking Survey
Authors: Barry Adam E. , Goodson Patricia
Published: July 2011

Purpose.

Report on the development and psychometric testing of a theoretically and evidence-grounded instrument, the Characteristics of Responsible Drinking Survey (CHORDS).

Design.

Instrument subjected to four phases of pretesting (cognitive validity, cognitive and motivational qualities, pilot test, and item evaluation) and a final posttest implementation.

Setting.

Large public university in Texas.

Subjects.

Randomly selected convenience sample (n = 729) of currently enrolled students.

Measures.

This 78-item questionnaire measures individuals' responsible drinking beliefs, motivations, intentions, and behaviors. Cronbach α, split-half reliability, principal components analysis and Spearman ρ were conducted to investigate reliability, stability, and validity.

Results.

Measures in the CHORDS exhibited high internal consistency reliability and strong correlations of split-half reliability. Factor analyses indicated five distinct scales were present, as proposed in the theoretical model. Subscale composite scores also exhibited a correlation to alcohol consumption behaviors, indicating concurrent validity.

Conclusions.

The CHORDS represents the first instrument specifically designed to assess responsible drinking beliefs and behaviors. It was found to elicit valid and reliable data among a college student sample. This instrument holds much promise for practitioners who desire to empirically investigate dimensions of responsible drinking.
Physician Advice on Exercise and Diet in a U.S. Sample of Obese Mexican-American Adults
Authors: Nguyen Ha T. , Markides Kyriakos S. , Winkleby Marilyn A.
Published: July 2011

Purpose.

To document the prevalence of obese Mexican-Americans never advised by health professionals regarding exercise and diet, and to determine risk factors for no advice.

Methods.

Data came from 1787 obese Mexican-American adults (body mass index ≥ 30; age ≥ 18 years) in the Medical Expenditure Panel Survey. The survey included self-reported receipt of health care provider advice on exercise and diet as well as sociodemographic, health-related, and provider-related factors. Multivariable logistic regression models were performed separately for advice regarding exercise and advice regarding diet.

Results.

Overall, 45% of respondents reported that they had never received advice from a doctor or health care professional to exercise more, and 52% reported that they have received advice to eat fewer higher-fat/high-cholesterol foods. Men, nonmarried respondents, lower-educated respondents, those who preferred to speak Spanish at home, and those without comorbid chronic conditions were less likely to receive advice.

Discussion.

Results suggest that obese Mexican-Americans are insufficiently advised by health care providers regarding exercise and diet. Given the seriousness of obesity-related health risks and the increasing prevalence of overweight status and obesity among Mexican-Americans, it is vital that providers are involved in finding ways to effectively educate and/or treat overweight patients.
Increasing Consumer Demand among Medicaid Enrollees for Tobacco Dependence Treatment: The Wisconsin “Medicaid Covers It” Campaign
Authors: Keller Paula A. , Christiansen Bruce , Kim Su-Young , Piper Megan E. , Redmond Lezli , Adsit Robert , Fiore Michael C.
Published: July 2011

Purpose.

Smoking prevalence among Medicaid enrollees is higher than among the general population, but use of evidence-based cessation treatment is low. We evaluated whether a communications campaign improved cessation treatment utilization.

Design.

Quasi-experimental.

Setting.

Wisconsin.

Subjects.

Enrollees in the Wisconsin Family Medicaid program. The average monthly enrollment during the study period was approximately 170,000 individuals.

Intervention.

Print materials for clinicians and consumers distributed to 13 health maintenance organizations (HMOs) serving Wisconsin Medicaid HMO enrollees.

Measures.

Wisconsin Medicaid pharmacy claims data for smoking cessation medications were analyzed before and after a targeted communications campaign. HMO enrollees were the intervention group. Fee-for-service enrollees were a quasi-experimental comparison group. Quit Line utilization data were also analyzed.

Analysis.

Pharmacotherapy claims and number of registered Quit Line callers were compared precampaign and postcampaign.

Results.

Precampaign, cessation pharmacotherapy claims declined for the intervention group and increased slightly for the comparison group (t = 2.29, p = .03). Postcampaign, claims increased in both groups. However, the rate of increase in the intervention group was significantly greater than in the comparison group (t = −2.2, p = .04). A statistically significant increase was also seen in the average monthly number of Medicaid enrollees that registered for Quit Line services postcampaign compared to precampaign (F [1,22] = 7.19, p = .01).

Conclusion.

This natural experiment demonstrated statistically significant improvements in both pharmacotherapy claims and Quit Line registrations among Medicaid enrollees. These findings may help inform other states' efforts to improve cessation treatment utilization.
An Individually Based Lifestyle Intervention for Workers at Risk for Cardiovascular Disease: A Process Evaluation
Authors: Groeneveld Iris F. , Proper Karin I. , Absalah Saida , van der Beek Allard J. , van Mechelen Willem
Published: July 2011

Purpose.

Evaluate counselors' adherence to an intervention protocol, counselors' competence, and the associations between three process indicators and body weight at follow-up in a 6-month individually based lifestyle intervention for construction workers.

Design.

Process evaluation with qualitative and quantitative data.

Setting.

Occupational health service.

Subjects.

A total of 408 male construction workers with an elevated risk of cardiovascular disease received the intervention, and 27 occupational health professionals delivered the intervention.

Intervention.

Seven counseling sessions, the first during which four prescribed items had to be discussed. Motivational interviewing (MI) was used as a counseling technique.

Measures and Analysis.

The number of sessions and the items discussed were registered by the counselors. Adherence to MI was determined by expert scoring of transcripts of random segments of 19 counseling sessions. Counselors' competence was rated by participants and counselors separately. Associations between three process indicators and body weight at follow-up were determined by linear and logistic regression analyses.

Results.

Two-thirds of all participants attended five or more sessions, and 38.5% attended all seven sessions. In 90.2% of all cases, the counselor discussed all obligatory items in the first session. MI adherence was reached in one audiotaped fragment. Most (86.3%) of all participants agreed with the counselor being competent. Neither counselors' competence nor number of sessions or items discussed was significantly associated with body weight loss.

Conclusions.

Performing five sessions and discussing four prescribed items was feasible for the counselors, whereas performing MI was not. Still, participants were positive about the counselors' competence and willing to attend the intervention sessions. Investigators are encouraged to report the evaluation of their intervention process to improve future lifestyle interventions in research or in practice.
Pesquisas com temáticas arquivísticas na Ciência da Informação: mapeamento das principais tendências
Authors: Marques Angélica Alves da Cunha
Published: July 2011

Este trabalho apresenta parte dos resultados de uma pesquisa de doutoramento, cujo objetivo é identificar as interlocuções entre a Arquivologia mundial e a nacional a partir das tendências internacionais presentes no desenvolvimento da área no Brasil. Nesse sentido, mapeia, nas dissertações e teses com temáticas arquivísticas produzidas nos vários programas de pós-graduação em Ciência da Informação, as referências bibliográficas arquivísticas, os autores e as obras de interesse direto da área, os países, períodos e idiomas de publicação. O universo da pesquisa aqui apresentado contempla cinquenta dissertações e teses desenvolvidas em oito programas de pós-graduação em Ciência da Informação de universidades brasileiras identificadas no Banco de Teses da CAPES. A partir da análise das referências bibliográficas arquivísticas dessas pesquisas, observa-se: a sua concentração nos programas de pós-graduação em Ciência da Informação da UFMG e UnB; a predominância da sua publicação no Brasil nos anos 1990 e em português (inclusive traduções). Há uma aproximação entre o número total de autores internacionais e nacionais mapeados, embora esses últimos sutilmente se destaquem. As trinta maiores frequências de referências arquivísticas por autor corroboram esse resultado, apontando a prevalência de brasileiros e de canadenses. As trinta maiores frequências de obras citadas também se relacionam, majoritariamente, a autores brasileiros. O mapeamento desses indicadores, numa análise entrecruzada, reflete os movimentos das tendências internacionais em interlocução com a Arquivologia brasileira, que, embora tenha um estatuto híbrido em razão dessas tendências, já apresenta uma produção científica consolidada, fortemente comunicada a partir das referências a autores e obras nacionais citadas em dissertações e teses com temáticas na área.
Políticas arquivísticas e suas implicações na preservação, no acesso e no uso dos documentos
Authors: Oliveira Rose Tenório de
Published: July 2011

Este estudo propõe discutir as implicações que a inexistência de políticas arquivísticas pode ter na preservação de acervos documentais. Leva em consideração que a preservação documental tem como objetivo garantir o acesso e o uso dos documentos, uma vez que o manuseio incorreto durante uma pesquisa é um dos vários fatores degradantes que afetam os acervos. Procura elencar tanto as dificuldades existentes nesse campo, quanto explicar que a preservação documental consiste em um trabalho de gestão onde o que está em jogo é o planejamento para definição de prioridades de ação.
Northern Hemisphere atmospheric influence of the solar proton events and ground level enhancement in January 2005
Authors: Jackman C. H. , Marsh D. R. , Vitt F. M. , Roble R. G. , Randall C. E. , Bernath P. F. , Funke B. , López-Puertas M. , Versick S. , Stiller G. P. , Tylka A. J. , Fleming E. L.
Published: July 2011

Abstract. Solar eruptions in early 2005 led to a substantial barrage of charged particles on the Earth's atmosphere during the 16–21 January period. Proton fluxes were greatly increased during these several days and led to the production of HOx (H, OH, HO2) and NOx (N, NO, NO2), which then caused the destruction of ozone. We focus on the Northern polar region, where satellite measurements and simulations with the Whole Atmosphere Community Climate Model (WACCM3) showed large enhancements in mesospheric HOx and NOx constituents, and associated ozone reductions, due to these solar proton events (SPEs). The WACCM3 simulations show enhanced short-lived OH and HO2 concentrations throughout the mesosphere in the 60–82.5° N latitude band due to the SPEs for most days in the 16–21 January 2005 period, somewhat higher in abundance than those observed by the Aura Microwave Limb Sounder (MLS). These HOx enhancements led to huge predicted and MLS-measured ozone decreases of greater than 40 % throughout most of the northern polar mesosphere during the SPE period. Envisat Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) measurements of hydrogen peroxide (H2O2) show increases throughout the stratosphere with highest enhancements of about 60 pptv in the lowermost mesosphere over the 16–18 January 2005 period due to the solar protons. WACCM3 predictions indicate H2O2 enhancements over the same time period of about three times that amount. Measurements of nitric acid (HNO3) by both MLS and MIPAS show an increase of about 1 ppbv above background levels in the upper stratosphere during 16–29 January 2005. WACCM3 simulations show only minuscule HNO3 increases (<0.05 ppbv) in the upper stratosphere during this time period. Polar mesospheric enhancements of NOx are computed to be greater than 50 ppbv during the SPE period due to the small loss rates during winter. Computed NOx increases, which were statistically significant at the 95 % level, lasted about a month past the SPEs. The SCISAT-1 Atmospheric Chemistry Experiment Fourier Transform Spectrometer NOx measurements and MIPAS NO2 measurements for the polar Northern Hemisphere are in reasonable agreement with these predictions. An extremely large ground level enhancement (GLE) occurred during the SPE period on 20 January 2005. We find that protons of energies 300 to 20 000 MeV, associated with this GLE, led to very small enhanced lower stratospheric odd nitrogen concentrations of less than 0.1 % and ozone decreases of less than 0.01 %.
A new method to detect long term trends of methane (CH4) and nitrous oxide (N2O) total columns measured within the NDACC ground-based high resolution solar FTIR network
Authors: Angelbratt J. , Mellqvist J. , Blumenstock T. , Borsdorff T. , Brohede S. , Duchatelet P. , Forster F. , Hase F. , Mahieu E. , Murtagh D. , Petersen A. K. , Schneider M. , Sussmann R. , Urban J.
Published: July 2011

Abstract. Total columns measured with the ground-based solar FTIR technique are highly variable in time due to atmospheric chemistry and dynamics in the atmosphere above the measurement station. In this paper, a multiple regression model with anomalies of air pressure, total columns of hydrogen fluoride (HF) and carbon monoxide (CO) and tropopause height are used to reduce the variability in the methane (CH4) and nitrous oxide (N2O) total columns to estimate reliable linear trends with as small uncertainties as possible. The method is developed at the Harestua station (60° N, 11° E, 600 m a.s.l.) and used on three other European FTIR stations, i.e. Jungfraujoch (47° N, 8° E, 3600 m a.s.l.), Zugspitze (47° N, 11° E, 3000 m a.s.l.), and Kiruna (68° N, 20° E, 400 m a.s.l.). Linear CH4 trends between 0.13 ± 0.01-0.25 ± 0.02 % yr−1 were estimated for all stations in the 1996-2009 period. A piecewise model with three separate linear trends, connected at change points, was used to estimate the short term fluctuations in the CH4 total columns. This model shows a growth in 1996–1999 followed by a period of steady state until 2007. From 2007 until 2009 the atmospheric CH4 amount increases between 0.57 ± 0.22–1.15 ± 0.17 % yr−1. Linear N2O trends between 0.19 ± 0.01–0.40 ± 0.02 % yr−1 were estimated for all stations in the 1996-2007 period, here with the strongest trend at Harestua and Kiruna and the lowest at the Alp stations. From the N2O total columns crude tropospheric and stratospheric partial columns were derived, indicating that the observed difference in the N2O trends between the FTIR sites is of stratospheric origin. This agrees well with the N2O measurements by the SMR instrument onboard the Odin satellite showing the highest trends at Harestua, 0.98 ± 0.28 % yr−1, and considerably smaller trends at lower latitudes, 0.27 ± 0.25 % yr−1. The multiple regression model was compared with two other trend methods, the ordinary linear regression and a Bootstrap algorithm. The multiple regression model estimated CH4 and N2O trends that differed up to 31 % compared to the other two methods and had uncertainties that were up to 300 % lower. Since the multiple regression method were carefully validated this stresses the importance to account for variability in the total columns when estimating trend from solar FTIR data.
Development of a simple unified volatility-based scheme (SUVS) for secondary organic aerosol formation using genetic algorithms
Authors: Xia A. G. , Stroud C. A. , Makar P. A.
Published: July 2011

Abstract. A new method is proposed to simplify complex atmospheric chemistry reaction schemes, while preserving SOA formation properties, using genetic algorithms. The method is first applied in this study to the gas-phase α-pinene oxidation scheme. The simple unified volatility-based scheme (SUVS) reflects the multi-generation evolution of chemical species from a near-explicit master chemical mechanism (MCM) and, at the same time, uses the volatility-basis set speciation for condensable products. The SUVS also unifies reactions between SOA precursors with different oxidants under different atmospheric conditions. A total of 412 unknown parameters (product yields of parameterized products, reaction rates, etc.) from the SUVS are estimated by using genetic algorithms operating on the detailed mechanism. The number of organic species was reduced from 310 in the detailed mechanism to 31 in the SUVS. Output species profiles, obtained from the original subset of the MCM reaction scheme for α-pinene oxidation, are reproduced with maximum fractional error at 0.10 for scenarios under a wide range of ambient HC/NOx conditions. Ultimately, the same SUVS with updated parameters could be used to describe the SOA formation from different precursors.
Observations of ice nuclei and heterogeneous freezing in a Western Pacific extratropical storm
Authors: Stith J. L. , Twohy C. H. , DeMott P. J. , Baumgardner D. , Campos T. , Gao R. , Anderson J.
Published: July 2011

Abstract. In situ airborne sampling of refractory black carbon (rBC) particles and Ice Nuclei (IN) was conducted in and near an extratropical cyclonic storm in the western Pacific Ocean during the Pacific Dust Experiment, PACDEX, in the spring of 2007. Airmass origins were from Eastern Asia. Clouds associated primarily with the warm sector of the storm were sampled at various locations and altitudes. Cloud hydrometeors were evaporated by a counterflow virtual impactor (CVI) and the residuals were sampled by a single particle soot photometer (SP2) instrument, a continuous flow diffusion chamber ice nucleus detector (CFDC) and collected for electron microscope analysis. In clouds containing large ice particles, multiple residual particles were observed downstream of the CVI for each ice particle sampled on average. The fraction of rBC compared to total particles in the residual particles increased with decreasing condensed water content, while the fraction of IN compared to total particles did not, suggesting that the scavenging process for rBC is different than for IN. In the warm sector storm midlevels at temperatures where heterogeneous freezing is expected to be significant (here −24 to −29 °C), IN concentrations from ice particle residuals generally agreed with simultaneous measurements of total ice concentrations or were higher in regions where aggregates of crystals were found, suggesting heterogeneous freezing as the dominant ice formation process in the mid levels of these warm sector clouds. Lower in the storm, at warmer temperatures, ice concentrations were affected by aggregation and were somewhat less than measured IN concentrations at colder temperatures. The results are consistent with ice particles forming at storm mid-levels by heterogeneous freezing on IN, followed by aggregation and sedimentation to lower altitudes. Compositional analysis of the aerosol and back trajectories of the air in the warm sector suggested a possible biomass burning source for much of the aerosol. Comparison of the particles from the CFDC with the other aerosol in the residuals of ice particles suggested that the largest portion of IN had similar inferred origins (from biomass burning with minor amounts of rBC) as the other aerosol, but contained slightly elevated amounts of calcium and less influence from sea salt.
Simultaneous retrieval of aerosol and cloud properties during the MILAGRO field campaign
Authors: Knobelspiesse K. , Cairns B. , Redemann J. , Bergstrom R. W. , Stohl A.
Published: July 2011

Abstract. Estimation of Direct Climate Forcing (DCF) due to aerosols in cloudy areas has historically been a difficult task, mainly because of a lack of appropriate measurements. Recently, passive remote sensing instruments have been developed that have the potential to retrieve both cloud and aerosol properties using polarimetric, multiple view angle, and multi spectral observations, and therefore determine DCF from aerosols above clouds. One such instrument is the Research Scanning Polarimeter (RSP), an airborne prototype of a sensor on the NASA Glory satellite, which unfortunately failed to reach orbit during its launch in March of 2011. In the spring of 2006, the RSP was deployed on an aircraft based in Veracruz, Mexico, as part of the Megacity Initiative: Local and Global Research Observations (MILAGRO) field campaign. On 13 March, the RSP over flew an aerosol layer lofted above a low altitude marine stratocumulus cloud close to shore in the Gulf of Mexico. We investigate the feasibility of retrieving aerosol properties over clouds using these data. Our approach is to first determine cloud droplet size distribution using the angular location of the cloud bow and other features in the polarized reflectance. The selected cloud was then used in a multiple scattering radiative transfer model optimization to determine the aerosol optical properties and fine tune the cloud size distribution. In this scene, we were able to retrieve aerosol optical depth, the fine mode aerosol size distribution parameters and the cloud droplet size distribution parameters to a degree of accuracy required for climate modeling. This required assumptions about the aerosol vertical distribution and the optical properties of the coarse aerosol size mode. A sensitivity study was also performed to place this study in the context of future systematic scanning polarimeter observations, which found that the aerosol complex refractive index can also be observed accurately if the aerosol optical depth is larger than roughly 0.8 at a wavelength of (0.555 μm).
Natural and anthropogenic atmospheric mercury in the European Arctic: a fractionation study
Authors: Steen A. O. , Berg T. , Dastoor A. P. , Durnford D. A. , Engelsen O. , Hole L. R. , Pfaffhuber K. A.
Published: July 2011

Abstract. Gaseous elemental mercury (GEM) is converted to reactive gaseous mercury (RGM) during springtime Atmospheric Mercury Depletion Events (AMDE). This study reports the longest time series of GEM, RGM and particle-bound mercury (PHg) concentrations from a European Arctic site. From 27 April 2007 until 31 December 2008 composite GEM, RGM and PHg measurements were conducted in Ny-Ålesund (78° 54′ N, 11° 53′ E). The average concentrations of the complete dataset were 1.6 ± 0.3 ng m−3, 8 ± 13 pg m−3 and 8 ± 25 pg m−3 for GEM, RGM and PHg, respectively. For the complete dataset the atmospheric mercury distribution was 99 % GEM, whereas RGM and PHg constituted <1 %. The study revealed a seasonal distribution of GEM, RGM and PHg previously undiscovered in the Arctic. Increased concentrations of RGM were observed during the insolation period from March through August, while increased PHg concentrations occurred almost exclusively during the spring AMDE period in March and April. The elevated RGM concentrations suggest that atmospheric RGM deposition also occurs during the polar summer. RGM was suggested as the precursor for the PHg existence, but long range transportation of PHg has to be taken into consideration. Still there remain gaps in the knowledge of how RGM and PHg are related in the environment. RGM and PHg accounted for on average about 10 % of the depleted GEM during AMDEs. Although speculative, the fairly low RGM and PHg concentrations supported by the predominance of PHg with respect to RGM and no clear meteorological regime associated with these AMDEs would all suggest the events to be of non-local origin. With some exceptions, no clear meteorological regime was associated with the GEM, RGM and PHg concentrations throughout the year.
TransCom model simulations of CH4 and related species: linking transport, surface flux and chemical loss with CH4 variability in the troposphere and lower stratosphere
Authors: Patra P. K. , Houweling S. , Krol M. , Bousquet P. , Belikov D. , Bergmann D. , Bian H. , Cameron-Smith P. , Chipperfield M. P. , Corbin K. , Fortems-Cheiney A. , Fraser A. , Gloor E. , Hess P. , Ito A. , Kawa S. R. , Law R. M. , Loh Z. , Maksyutov S. , Meng L. , Palmer P. I. , Prinn R. G. , Rigby M. , Saito R. , Wilson C.
Published: July 2011

Abstract. A transport model intercomparison experiment (TransCom-CH4) has been designed to investigate the roles of surface emissions, transport and chemical loss in simulating the global methane distribution. Model simulations were conducted using twelve models and four model variants and results were archived for the period of 1990–2007. The transport and removal of six CH4 tracers with different emission scenarios were simulated, with net global emissions of 513 ± 9 and 514 ± 14 Tg CH4 yr−1 for the 1990s and 2000s, respectively. Additionally, sulfur hexafluoride (SF6) was simulated to check the interhemispheric transport, radon (222Rn) to check the subgrid scale transport, and methyl chloroform (CH3CCl3) to check the chemical removal by the tropospheric hydroxyl radical (OH). The results are compared to monthly or annual mean time series of CH4, SF6 and CH3CCl3 measurements from 8 selected background sites, and to satellite observations of CH4 in the upper troposphere and stratosphere. Most models adequately capture the vertical gradients in the stratosphere, the average long-term trends, seasonal cycles, interannual variations and interhemispheric gradients at the surface sites for SF6, CH3CCl3 and CH4. The vertical gradients of all tracers between the surface and the upper troposphere are consistent within the models, revealing vertical transport differences between models. We find that the interhemispheric exchange rate (1.39 ± 0.18 yr) derived from SF6 is faster by about 11 % in the 2000s compared to the 1990s. Up to 60 % of the interannual variations in the forward CH4 simulations can be explained by accounting for the interannual variations in emissions from biomass burning and wetlands. We also show that the decadal average growth rate likely reached equilibrium in the early 2000s due to the flattening of anthropogenic emission growth since the late 1990s. The modeled CH4 budget is shown to depend strongly on the troposphere-stratosphere exchange rate and thus to the model's vertical grid structure and circulation in the lower stratosphere. The 15-model median CH4 and CH3CCl3 atmospheric lifetimes are estimated to be 9.99 ± 0.08 and 4.61 ± 0.13 yr, respectively, with little interannual variability due to transport and temperature as noted by the ± 1 σ.
Global distribution and climate forcing of marine organic aerosol – Part 1: Model improvements and evaluation
Authors: Meskhidze N. , Xu J. , Gantt B. , Zhang Y. , Nenes A. , Ghan S. J. , Liu X. , Easter R. , Zaveri R.
Published: July 2011

Abstract. Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM5) with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7). Emissions of marine primary organic aerosols (POA), phytoplankton-produced isoprene- and monoterpenes-derived secondary organic aerosols (SOA) and methane sulfonate (MS−) are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr−1, for the Gantt et al. (2011) and Vignati et al. (2010) emission parameterizations, respectively. Marine sources of SOA and particulate MS− (containing both sulfur and carbon atoms) contribute an additional 0.2 and 5.1 Tg yr−1, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ng m−3, with values up to 400 ng m−3 over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM) with POA concentrations from the two emission parameterizations shows that both Gantt et al. (2011) and Vignati et al. (2010) formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011) parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN). The largest increases (up to 20 %) in CCN (at a supersaturation (S) of 0.2 %) number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming marine organics are internally-mixed with sea-salt provides diverse results with increase and decrease in the concentration of CCN over different parts of the ocean. The sign of the CCN change due to the addition of marine organics to sea-salt aerosol is determined by the relative significance of the increase in mean modal diameter due to addition of mass, and the decrease in particle hygroscopicity due to compositional changes in marine aerosol. Based on emerging evidence for increased CCN concentration over biologically active surface ocean areas/periods, our study suggests that treatment of sea spray in global climate models (GCMs) as an internal mixture of marine organic aerosols and sea-salt will likely lead to an underestimation in CCN number concentration.
A trading-space-for-time approach to probabilistic continuous streamflow predictions in a changing climate
Authors: Singh R. , Wagener T. , van Werkhoven K. , Mann M. , Crane R.
Published: July 2011

Abstract. Understanding the implications of potential future climatic conditions for hydrologic services and hazards is a crucial and current science question. The common approach to this problem is to force a hydrologic model, calibrated on historical data or using a priori parameter estimates, with future scenarios of precipitation and temperature. Recent studies suggest that the climatic regime of the calibration period is reflected in the resulting parameter estimates and that the model performance can be negatively impacted if the climate for which projections are made is significantly different from that during calibration. We address this issue by introducing a framework for probabilistic streamflow predictions in a changing climate wherein we quantify the impact of climate on model parameters. The strategy extends a regionalization approach (used for predictions in ungauged basins) by trading space-for-time to account for potential parameter variability in a future climate that is beyond the historically observed one. The developed methodology was tested in five US watersheds located in dry to wet climates using synthetic climate scenarios generated by increasing the historical mean temperature from 0 to 8 °C and by changing historical mean precipitation from −30 % to +40 % of the historical values. Validation on historical data shows that changed parameters perform better if future streamflow differs from historical by more than 25 %. We found that the thresholds of climate change after which the streamflow projections using adjusted parameters were significantly different from those using fixed parameters were 0 to 2 °C for temperature change and −10 % to 20 % for precipitation change depending upon the aridity of the watershed. Adjusted parameter sets simulate a more extreme watershed response for both high and low flows.
Reformulating the full-Stokes ice sheet model for a more efficient computational solution
Authors: Dukowicz J. K.
Published: July 2011

Abstract. The first-order or Blatter-Pattyn ice sheet model is an attractive alternative to the full Stokes model in many applications because of its reduced computational demands, in spite of an approximate stress tensor and a limitation to small basal boundary slopes. In contrast, the full unapproximated Stokes ice sheet model is more difficult to solve and computationally more expensive. This is due to the fact that while both models arise from a variational principle, the Blatter-Pattyn variational functional is positive-definite and involves just the horizontal velocity components, while the Stokes functional is indefinite and involves all three velocity components, as well as the pressure. These unfavorable properties arise because Stokes flow is treated as a constrained minimization problem where the pressure acts as a Lagrange multiplier that enforces incompressibility or zero velocity divergence. To alleviate these problems we reformulate the full-Stokes problem as an unconstrained, positive-definite minimization problem, quite analogous to the Blatter-Pattyn model but without the associated approximations, by introducing a velocity field that is already divergence-free and satisfies appropriate boundary conditions, thus dispensing with the need for a pressure. Such a velocity field is obtained by vertically integrating the continuity equation to obtain the vertical velocity as a function of the horizontal velocity components, as is done in the Blatter-Pattyn model. This leads to a reduced system for just the horizontal velocity components, again just as in the Blatter-Pattyn model. We thus obtain not only a reformulated action principle, which itself is sufficient for obtaining an efficient discrete model, but also a novel set of Euler-Lagrange partial differential equations and boundary conditions that specify the Stokes problem in terms of just the horizontal velocities. The derivations are performed not only for the common case of an ice sheet in contact with and sliding along the bed, which again is analogous to the Blatter-Pattyn model, but also for more general situations, such as for a floating ice shelf.
Pancreatic Islets from Non-Heart-Beating Donor Pig: Two-layer Preservation Method in an in Vitro Porcine Model
Authors: Gioviale Maria Concetta , Damiano Giuseppe , Palumbo Vincenzo Davide , Bellavia Maurizio , Cacciabaudo Francesco , Cassata Giovanni , Puleio Roberto , Altomare Roberta , Lo Monte Attilio Ignazio
Published: July 2011

Purpose

Pancreata from non-heart beating donors could represent an unlimited source of islets if their cell viability can be efficiently preserved during the time necessary to process the organs by the use of a better solution of preservation compared to the classic University of Wisconsin solution. The aim of this study was to determine whether it is possible to obtain functioning “alive islets” from non-heart-beating donors by comparing, on a porcine model, the classic “UW ice-store” method with a two-layer cold storage method (TLM) using oxygenated Perfluorocarbons (PFC) and UW.

Methods

Whole pancreata were harvested from 20 NHBDs female pigs with similar characteristics and preserved for 4 h in UW solution (n=10) or TLM (UW/PFC) solution (n=10). The isolated islets were then evaluated for number, viability, purity, and insulin secretion, also estimated after 8 weeks of cryopreservation.

Results

The total number of islets obtained from isolation, and their function assayed by the insulin stimulation index, before and after cryopreservation, showed a higher value in the TLM group. No significative differences in terms of purity and viability before and after cryopreservation were found when comparing the two groups.

Conclusions

TLM solution for NHBDs porcine pancreata with cold ischemia time lower than 4 h offers significant advantages over UW solution storage, thereby increasing the isolation yield and isolation success rate of the pancreatic porcine islets.
Role of the Hemodialysis Vascular Access Type in Inflammation Status and Monocyte Activation
Authors: Colì Luigi , Donati Gabriele , Cappuccilli Maria L. , Cianciolo Giuseppe , Comai Giorgia , Cuna Vania , Carretta Elisa , La Manna Gaetano , Stefoni Sergio
Published: July 2011

Purpose

The aim of this study was to ascertain the role of different vascular access types in inflammatory status, monocyte activation, and senescence in hemodialysis patients.

Methods

We recruited 126 hemodialysis patients, including 51 with arterovenous fistula (AVF), 32 with arterovenous graft (AVG), and 43 with tunneled cuffed catheters (TCC). In dialysis patients enrolled in the study and in a control group of 40 healthy subjects, we measured the serum levels of albumin, CRP, IL-6, and TNF-α, the expression of CD14, CD44, and CD32 on monocyte surface, and the percentage of monocytes exhibiting a senescent phenotype (CD14+CD32+).

Results

The patients with AVG compared to those with AVF had: a) higher levels of CRP and TNF-α; b) increased expression of CD14 and CD32 on monocyte surface, with no difference in CD44 expression; c) no difference in the percentage of CD14+CD32+ monocytes. In the comparison of TCC vs. AVF group, we observed significantly higher values of: a) circulating inflammatory markers (CRP, IL-6, TNF-α); b) monocyte surface expression of cellular activation markers (CD14, CD44 and CD32); c) relative count of CD14+CD32+ monocytes. When comparing TCC vs. AVG group, we found: a) no difference in serum levels of CRP, IL-6, and TNF-α; b) no difference in the expression of CD14, CD44, and CD32 on monocyte surface; c) no difference in the percentage of CD14+CD32+ monocytes.

Conclusions

These results suggest that the use of AVG and TCC for dialysis vascular access is associated with serological and cellular indexes of inflammatory reaction, also resulting in a higher degree of monocyte activation and senescence.
Glucose but not N-Acetylglucosamine Accelerates in vitro Senescence of Human Peritoneal Mesothelial Cells
Authors: Ciszewicz Marta , Wu George , Tam Paul , Połubinska Alicja , Bręborowicz Andrzej
Published: July 2011

Background

Preservation of the mesothelial cells (MCs) is crucial for longevity of the peritoneal dialysis membrane. Glucose accelerates aging of MC and we tested whether N-acetylglucosamine (NAG) has an identical effect.

Methods

Replicative aging of MCs was studied during 10 passages performed every three days in cells cultured in standard medium or in medium supplemented with Glucose 30 mmol/L or NAG 30 mmol/L. Changes in population doubling time and β-galactosidase activity were used as an index of aging and compared with other cellular parameters.

Results

Repeated passages of MC cause their aging, as reflected by prolongation of the population doubling time, increased β-galactosidase activity, oxidative stress and release of cytokines. Healing of injured mesothelial monolayer is impaired in senescent cells. Glucose accelerates in vitro aging of MC, whereas NAG does not cause this effect.

Conclusions

Replacement of glucose with NAG in the dialysis fluid can slow down aging of MC.
Experience with Ulcerated, Bleeding Autologous Dialysis Fistulas
Authors: Jaffers Gregory J. , Fasola Carlos G.
Published: July 2011

Purpose

The incidence of ulcerated, bleeding, autologous, hemodialysis fistulas has been felt to be increasing in recent years. This review was undertaken to examine our experience with patients who presented with episodes of spontaneous bleeding in the presence of an ulcerated lesion over their autologous dialysis accesses.

Methods

A database of hemodialysis access procedures was reviewed for individuals with spontaneous bleeding from ulcerations. Twenty-four patients were identified with 28 ulcerating lesions over a ten-year period from 2001 to 2011. Each had at least a single episode of spontaneous bleeding. Treatment methods were reviewed including five techniques of surgical intervention.

Results

Two of 24 patients expired from major hemorrhagic events before obtaining surgical consultation (8.3%). Twenty-one patients (87.5%) underwent 28 surgical procedures for correction of the ulcers. One patient (4.1%) with simultaneous ulcers healed under antibiotic therapy during close observation in hospital. Simple suturing of the ulcer was found to be inconsistent in effectively maintaining hemostasis. Surgical excision of the ulcer with primary closure, vein patching of the fistula, or end-end anastomosis were equally effective in definitively correcting the problem.

Conclusions

The ulcerated autologous dialysis fistula is a life-threatening lesion and requires prompt surgical intervention to reduce mortality. The frequency of this problem appears to be increasing. Simple suturing of the ulcers was not consistently effective in remedying the problem and should be utilized as a temporizing measure until surgical correction can be undertaken. Fistulas can be uniformly salvaged with surgical intervention enabling uninterrupted dialysis treatments.
Pictures in Test Items: Effects on Response Time and Response Correctness
Authors: Saß Steffani , Wittwer Jörg , Senkbeil Martin , Köller Olaf
Published: June 2011

Although pictures are often added to text in items of educational tests, little is known about their influence on item solving. Therefore, we conducted an experiment in which we examined how pictures affected item solving. A total of N = 158 fourth‐grade students completed a physics knowledge test under one of six experimental conditions. The experimental conditions varied according to whether or not pictures were presented in the stem and in the answer options of the test items. The results showed that pictures in the stem and in the answer options increased the correctness with which students responded to the test items. This was particularly true for test items that required the application of relationships. In addition, response time was reduced when pictures were added to the answer options of the test items. Hence, pictures are an important feature of test items that produce changes in item processing. Copyright © 2011 John Wiley & Sons, Ltd.
Periodically Laser Patterned FeBSi Amorphous Ribbons: Phase Evolution and Mechanical Behavior
Authors: Harimkar Sandip P. , Paital Sameer R. , Wang Gangyao , Liaw Peter K. , Dahotre Narendra B.
Published: June 2011

The properties of amorphous alloys are significantly influenced by structural relaxation and partial/full crystallization induced by thermal annealing of the alloy. In this paper, the phase evolution and mechanical behavior of laser‐patterned FeBSi amorphous alloys are reported. The laser patterning was employed to cause localized thermal effects on the surface of amorphous ribbons. The laser irradiation with a lower fluence (12 J · cm−2) caused significant embrittlement of the alloy due to the structural relaxation. The partial crystallization of an amorphous alloy into α‐Fe(Si) was also observed with laser irradiation using higher laser fluences (15 and 17 J · cm−2). The embrittlement effect due to laser‐irradiation‐induced crystallization was more severe than that due to structural relaxation.
Platinum Phosphors Containing an Aryl‐modified β‐Diketonate: Unusual Effect of Molecular Packing on Photo‐ and Electroluminescence
Authors: Chen Chin‐Hsien , Wu Fang‐Iy , Tsai Yin‐Yen , Cheng Chien‐Hong
Published: June 2011

Three new FPt1 [(2‐(4′,6′‐difluorophenyl)pyridinato‐N,C2′)(2,4‐pentanedionato‐ O,O)Pt(II)] analogues, Ph‐FPt, CzP‐FPt, and mCzP‐FPt, chelated with a 3‐aryl‐substituted acac ligand were synthesized. As shown by the results of X‐ray diffraction, the nearest neighboring molecules in the FPt1, Ph‐FPt, and CzP‐FPt crystals have a Pt–Pt distance of ~4.5, 4.5, and 7.0 Å, respectively. In contrast, in the mCzP‐FPt crystals, the nearest neighboring molecules exhibit a Pt–Pt distance of only 3.49 Å. All four Pt complexes show the same monomeric emission spectrum in dilute solution. However, in the crystalline state, mCzP‐FPt with a clear Pt–Pt bimetallic interaction shows only the low‐energy orange broadband emission; complexes FPt1, Ph‐FPt, and CzP‐FPt without significant Pt–Pt interaction (Pt–Pt distance > 4 Å) give higher‐energy emission closely resembling that of the monomeric species. The results provide clear evidence that the Pt–Pt bimetallic interaction is responsible for the low‐energy broadband emission of these Pt complexes. Unlike in the crystalline state, all of the four platinum complexes in the thin film give only the low‐energy broadband emissions with some difference in wavelength. In a similar manner, these platinum complexes‐based, non‐doped electroluminescence (EL) devices also emit only low‐energy orange broadband light. The non‐doped EL device using CzP‐FPt as the emitter showed a very promising external quantum efficiency of 10%, nearly five times higher than that of the FPt1 control device. The higher EL efficiency of the CzP‐FPt non‐doped device is mainly ascribed to the lower concentration of Pt–Pt dimers that effectively suppresses the self‐quenching between the orange emissive dimers.
Highly Regio‐ and Stereoselective Iodohydroxylation of 1,2‐Allenylic Sulfoxides in the Presence of Benzyl Thiol
Authors: Wang Minyan , Fu Chunling , Ma Shengming
Published: June 2011

The iodohydroxylation of 1,2‐allenyl sulfoxides with iodine in the presence of benzyl thiol afforded 3‐hydroxy‐2‐iodo‐2(E)‐alkenyl sulfides in good yields and high regio‐ and stereoselectivities. In this reaction it was observed that the sulfoxide functionality was reduced to sulfide and the water in the reaction mixture plays an important role for the stereoselectivity observed. A mechanism involving the attack of benzyl thiol at the positively charged sulfur atom in the five‐membered intermediate 2 has been proposed.
Enhanced photocatalytic performance of nanocrystalline TiO2 membrane by both slow photons and stop‐band reflection of photonic crystals
Authors: Chen Sheng‐Li , Wang Ai‐Jun , Hu Chun‐Tian , Dai Chao , Benziger Jay B.
Published: June 2011

An nc‐TiO2/SnO2 inverse opal composite membrane was fabricated, the photo‐activity of which was significantly enhanced by utilizing both slow photons and stop‐band reflection of the photonic crystal layer. The materials of the photonic crystal layer must be transparent in the area of adsorption edge of the nc‐TiO2, so that SnO2, having much greater electronic band gap than TiO2, was used for the materials of the photonic crystal layer. The photonic band‐gap of the SnO2 photonic crystal was designed at the semiconductor band gap of TiO2 to harvest slow photons in the interface between the SnO2 layer and the TiO2 layer. The two layer structure makes it possible to couple the stop‐band reflectivity of the photonic layer to the photocatalyst. Composite membranes can improve solar energy harvesting and substantially improve photocatalysts for photolysis and photochemical degradation of environmental pollutants. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Nonlinear quality prediction for multiphase batch processes
Authors: Ge Zhiqiang , Song Zhihuan , Gao Furong
Published: June 2011

Typically, a multiphase batch process comprises several steady phases and transition periods. In steady phases, the data characteristics remain similar during the phase and have a significant repeatability from batch to batch; thus most data nonlinearities can be removed through the batch normalization step. In contrast, in each transition period, process observations vary with time and from batch to batch, so nonlinearities in the data may not be eliminated through batch normalization. To improve quality prediction performance, an efficient nonlinear modeling method—relevance vector machine (RVM) was introduced. RVMs were formulated for each transition period of the batch process, and for combining the results of different process phases. For process analysis, a phase contribution index and a variable contribution index are defined. Furthermore, detailed performance analyses on the prediction uncertainty and variation were also provided. The effectiveness of the proposed method is confirmed by an industrial example. © 2011 American Institute of Chemical Engineers AIChE J, 58: 1778–1787, 2012