bluuebunny/crossref_metadata_2025_split huggingface dataset:
The parametric g‐formula to estimate the effect of highly active antiretroviral therapy on incident AIDS or death
Authors: Westreich Daniel , Cole Stephen R. , Young Jessica G. , Palella Frank , Tien Phyllis C. , Kingsley Lawrence , Gange Stephen J , Hernán Miguel A. 
Published: April 2012

AbstractThe parametric g‐formula can be used to contrast the distribution of potential outcomes under arbitrary treatment regimes. Like g‐estimation of structural nested models and inverse probability weighting of marginal structural models, the parametric g‐formula can appropriately adjust for measured time‐varying confounders that are affected by prior treatment. However, there have been few implementations of the parametric g‐formula to date. Here, we apply the parametric g‐formula to assess the impact of highly active antiretroviral therapy on time to acquired immune deficiency syndrome (AIDS) or death in two US‐based human immunodeficiency virus cohorts including 1498 participants. These participants contributed approximately 7300 person‐years of follow‐up (49% exposed to highly active antiretroviral therapy) during which 382 events occurred and 259 participants were censored because of dropout. Using the parametric g‐formula, we estimated that antiretroviral therapy substantially reduces the hazard of AIDS or death (hazard ratio = 0.55; 95% confidence limits [CL]: 0.42, 0.71). This estimate was similar to one previously reported using a marginal structural model, 0.54 (95% CL: 0.38, 0.78). The 6.5‐year difference in risk of AIDS or death was 13% (95% CL: 8%, 18%). Results were robust to assumptions about temporal ordering, and extent of history modeled, for time‐varying covariates. The parametric g‐formula is a viable alternative to inverse probability weighting of marginal structural models and g‐estimation of structural nested models for the analysis of complex longitudinal data. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of Chewing Gum on Stress and Health: A Replication and Investigation of Dose–Response
Authors: Smith Andrew 
Published: April 2012

AbstractResearch suggests that chewing gum may be associated with reduced stress, depression and a reduced likelihood of having high cholesterol and blood pressure. The present study aimed to replicate these findings and extend them by examining dose–response. A web‐based survey was completed by a sample of 388 workers from public sector organisations (68.5% female; mean age: 42 years, range 17–64 years). The results showed that chewing gum was associated in a linear dose–response manner with lower levels of perceived stress (both at work and life in general), anxiety and depression. Occasional gum chewers also reported a reduced risk of high cholesterol and blood pressure. Intervention studies are now required to extend these findings, and the mechanisms underlying the effects reported here need further investigation. Copyright © 2012 John Wiley & Sons, Ltd.
Changing Museum Visitors’ Conceptions of Evolution
Authors: Spiegel Amy N. , Evans E. Margaret , Frazier Brandy , Hazel Ashley , Tare Medha , Gram Wendy , Diamond Judy 
Published: April 2012

AbstractWe examined whether a single visit to an evolution exhibition contributed to conceptual change in adult (n = 30), youth, and child (n = 34) museum visitors’ reasoning about evolution. The exhibition included seven current research projects in evolutionary science, each focused on a different organism. To frame this study, we integrated a developmental model of visitors’ understanding of evolution, which incorporates visitors’ intuitive beliefs, with a model of free-choice learning that includes personal, sociocultural, and contextual variables. Using pre- and post-measures, we assessed how visitors’ causal explanations about biological change, drawn from three reasoning patterns (evolutionary, intuitive, and creationist), were modified as a result of visiting the exhibition. Whatever their age, background beliefs, or prior intuitive reasoning patterns, visitors significantly increased their use of explanations from the evolutionary reasoning pattern across all measures and extended this reasoning across diverse organisms. Visitors also increased their use of one intuitive reasoning pattern, need-based (goal-directed) explanations, which, we argue, may be a step toward evolutionary reasoning. Nonetheless, visitors continued to use mixed reasoning (endorsing all three reasoning patterns) in explaining biological change. The personal, socio-cultural, and contextual variables were found to be related to these reasoning patterns in predictable ways. These findings are used to examine the structure of visitors’ reasoning patterns and those aspects of the exhibition that may have contributed to the gains in museum visitors’ understanding of evolution.
Socio-Environmental Health Analysis in Nogales, Sonora, Mexico
Authors: Norman Laura M. , Caldeira Felipe , Callegary James , Gray Floyd , O’ Rourke Mary Kay , Meranza Veronica , Van Rijn Saskia 
Published: April 2012

Abstract
In Nogales, Sonora, Mexico, some neighborhoods, or colonias, have intermittent delivery of water through pipes from the city of Nogales’s municipal water-delivery system while other areas lack piped water and rely on water delivered by truck or pipas. This research examined how lifestyles, water quality, and potential disease response, such as diarrhea, differs seasonally from a colonia with access to piped water as opposed to one using alternative water-delivery systems. Water samples were collected from taps or spigots at homes in two Nogales colonias. One colonia reflected high socio-environmental conditions where residents are supplied with municipal piped water (Colonia Lomas de Fatima); the second colonia reflected low socio-environmental conditions, lacking access to piped water and served by pipas (Colonia Luis Donaldo Colosio). A survey was developed and implemented to characterize perceptions of water quality, health impacts, and quality of life. Water samples were analyzed for microbial and inorganic water-quality parameters known to impact human health including, Escherichia coli (E. coli), total coliform bacteria, arsenic, and lead. A total of 21 households agreed to participate in the study (14 in Colosio and 7 in Fatima). In both colonias metal concentrations from water samples were all well below the United States Environmental Protection Agency’s (US EPA’s) maximum contaminant levels. E. coli concentrations exceeded the US EPA’s drinking-water standard in Colosio but not Fatima. Total coliform bacteria were present in over 50 % of households in both colonias. Microbial contamination was significantly higher in the summer than in the winter in both colonias. Resulting analysis suggests that residents in colonias without piped water are at a greater risk of gastrointestinal illness from consumption of compromised drinking water. Our survey corroborated reports of gastrointestinal illness in the summer months but not in the winter. Chloride was found to be significantly greater in Colosio (median 29.2 mg/L) although still below the US EPA’s maximum contaminant levels of 250 mg/L. Ongoing binational collaboration can promote mechanisms to improve water quality in cities located in the US–Mexico border.
Recycling gone bad: When the option to recycle increases resource consumption
Authors: Catlin Jesse R. , Wang Yitong 
Published: April 2012

AbstractIn this study, we propose that the ability to recycle may lead to increased resource usage compared to when a recycling option is not available. Supporting this hypothesis, our first experiment shows that consumers used more paper while evaluating a pair of scissors when the option to recycle was provided (vs. not provided). In a follow‐up field experiment, we find that the per person restroom paper hand towel usage increased after the introduction of a recycling bin compared to when a recycling option was not available. We conclude by discussing implications for research and policy.
Transformation of temporomandibular joint disc configuration in internal derangement patients using magnetic resonance imaging
Authors: Arayasantiparb Raweewan , Tsuchimochi Makoto , Mitrirattanakul Somsak 
Published: April 2012

AbstractPurpose: The normal disc configuration is biconcave; however, the deformed disc can be found in internal derangement (ID) of the temporomandibular joint (TMJ). The purpose of this study was to evaluate the relationship between the transformation patterns of TMJ disc configuration during mouth opening and disc displacement status, disc reduction ability and TMJ clinical symptoms.Methods: TMJ MR images from volunteers and ID patients were analyzed for closed and open mouth positions. MR images of ID patients were classified into 4 groups: symptomatic joint with anterior disc displacement with or without reduction (ADW or ADWo) and asymptomatic joint with ADW or ADWo. The disc configurations in both positions were categorized as biconcave, biplanar, convex or folded; then the patterns of transformation were observed.Results: For the ADW group, the most common disc configuration for closed and open mouth positions were biplanar (66.7%) and biconcave (86.3%). The transformation pattern was significantly related to disc reduction ability (p < 0.05).Conclusions: The transformation patterns of disc configuration during opening were related to anterior disc displacement and disc reduction ability.
Equation of motion for a sphere in non-uniform compressible flows
Authors: Parmar M. , Haselbacher A. , Balachandar S. 
Published: April 2012

AbstractLinearized viscous compressible Navier–Stokes equations are solved for the transient force on a spherical particle undergoing unsteady motion in an inhomogeneous unsteady ambient flow. The problem is formulated in a reference frame attached to the particle and the force contributions from the undisturbed ambient flow and the perturbation flow are separated. Using a density-weighted velocity transformation and reciprocal relation, the total force is first obtained in the Laplace domain and then transformed to the time domain. The total force is separated into the quasi-steady, inviscid unsteady, and viscous unsteady contributions. The above rigorously derived particle equation of motion can be considered as the compressible extension of the Maxey–Riley–Gatignol equation of motion and it incorporates interesting physics that arises from the combined effects of inhomogeneity and compressibility.
A new model of roll waves: comparison with Brock’s experiments
Authors: Richard G. L. , Gavrilyuk S. L. 
Published: April 2012

AbstractWe derive a mathematical model of shear flows of shallow water down an inclined plane. The non-dissipative part of the model is obtained by averaging the incompressible Euler equations over the fluid depth. The averaged equations are simplified in the case of weakly sheared flows. They are reminiscent of the compressible non-isentropic Euler equations where the flow enstrophy plays the role of entropy. Two types of enstrophies are distinguished: a small-scale enstrophy generated near the wall, and a large-scale enstrophy corresponding to the flow in the roller region near the free surface. The dissipation is then added in accordance with basic physical principles. The model is hyperbolic, the corresponding ‘sound velocity’ depends on the flow enstrophies. Periodic stationary solutions to this model describing roll waves were obtained. The solutions are in good agreement with the experimental profiles of roll waves measured in Brock’s experiments. In particular, the height of the vertical front of the waves, the shock thickness and the wave amplitude are well captured by the model.
ASSOCIATIONS BETWEEN HOUSEHOLD AND NEIGHBOURHOOD SOCIOECONOMIC STATUS AND SYSTOLIC BLOOD PRESSURE AMONG URBAN SOUTH AFRICAN ADOLESCENTS
Authors: GRIFFITHS PAULA L. , SHEPPARD ZOË A. , JOHNSON WILLIAM , CAMERON NOËL , PETTIFOR JOHN M. , NORRIS SHANE A. 
Published: April 2012

SummaryFactors resulting in high risk for cardiovascular disease have been well studied in high income countries, but have been less well researched in low/middle income countries. This is despite robust theoretical evidence of environmental transitions in such countries which could result in biological adaptations that lead to increased hypertension and cardiovascular disease risk. Data from the South African Birth to Twenty cohort, Bone Health sub-sample (n=358, 47% female), were used to model associations between household socioeconomic status (SES) in infancy, household/neighbourhood SES at age 16 years, and systolic blood pressure (multivariate linear regression) and risk for systolic pre-hypertension (binary logistic regression). Bivariate analyses revealed household/neighbourhood SES measures that were significantly associated with increased systolic blood pressure. These significant associations included improved household sanitation in infancy/16 years, caregiver owning the house in infancy and being in a higher tertile (higher SES) of indices measuring school problems/environment or neighbourhood services/problems/crime at 16 years of age. Multivariate analyses adjusted for sex, maternal age, birth weight, parity, smoking, term birth, height/body mass index at 16 years. In adjusted analyses, only one SES variable remained significant for females: those in the middle tertile of the crime prevention index had higher systolic blood pressure (β=3.52, SE=1.61) compared with the highest tertile (i.e. those with the highest crime prevention). In adjusted analyses, no SES variables were significantly associated with the systolic blood pressure of boys, or with the risk of systolic pre-hypertension in either sex. The lack of association between SES and systolic blood pressure/systolic pre-hypertension at age 16 years is consistent with other studies showing an equalization of adolescent health inequalities. Further testing of the association between SES and systolic blood pressure would be recommended in adulthood to see whether the lack of association persists.
Changes in severity of depressive symptoms and mortality: the Italian Longitudinal Study on Aging
Authors: Scafato E. , Galluzzo L. , Ghirini S. , Gandin C. , Rossi A. , Solfrizzi V. , Panza F. , Di Carlo A. , Maggi S. , Farchi G. 
Published: April 2012

BackgroundDepression is recognized as being associated with increased mortality. However, there has been little previous research on the impact of longitudinal changes in late-life depressive symptoms on mortality, and of their remission in particular.MethodAs part of a prospective, population-based study on a random sample of 5632 subjects aged 65–84 years, with a 10-year follow-up of vital status, depressive symptoms were assessed by the 30-item Italian version of the Geriatric Depression Scale (GDS). The number of participants in the GDS measurements was 3214 at baseline and 2070 at the second survey, 3 years later. Longitudinal changes in depressive symptoms (stable, remitted, worsened) were examined in participants in both evaluations (n=1941). Mortality hazard ratios (MHRs) according to severity of symptoms and their changes over time were obtained by means of Cox proportional hazards regression models, adjusting for age and other potentially confounding factors.ResultsSeverity is significantly associated with excess mortality in both genders. Compared to the stability of depressive symptoms, a worsened condition shows a higher 7-year mortality risk [MHR 1.46, 95% confidence interval (CI) 1.15–1.84], whereas remission reduces by about 40% the risk of mortality in both genders (women MHR 0.55, 95% CI 0.32–0.95; men MHR 0.59, 95% CI 0.37–0.93). Neither sociodemographic nor medical confounders significantly modified these associations.ConclusionsConsistent with previous reports, the severity and persistence of depression are associated with higher mortality risks. Our findings extend the magnitude of the association demonstrating that remission of symptoms is related to a significant reduction in mortality, highlighting the need to enhance case-finding and successful treatment of late-life depression.
Quality of life among disabled older adults without cognitive impairment and its relation to attendance in day care centres
Authors: IECOVICH ESTHER , BIDERMAN AYA 
Published: April 2012

ABSTRACTDay care centres intend to improve the quality of life of disabled older adults. The aims of the paper are to: (a) examine the extent to which users of day care centres experience higher levels of quality of life compared to their peers who are non-users; and (b) to explore the relationships between the length of use and frequency of weekly attendance at day care centres and quality of life. This is a case-control study with a sample of 817 respondents, of whom 417 were users of day care centres and 400 were non-users, matched by age, gender and family physician. The study was conducted in 12 day care centres in the southern region of Israel. Data collection included face-to-face interviews using a structured questionnaire. Quality of life was found to be significantly related to the use of day care centres, but length and frequency of attendance were insignificant in explaining quality of life among users of day care centres. The study demonstrated that users of day care centres have a higher quality of life, but in a cross-sectional study we cannot prove causality. Therefore, more research using quasi-experimental and longitudinal research designs is necessary to assess causality between use and attendance at day care centres on users' quality of life.
Rethinking epistemic communities twenty years later
Authors: CROSS MAI'A K. DAVIS 
Published: April 2012

AbstractThe concept of epistemic communities – professional networks with authoritative and policy-relevant expertise – is well-known thanks to a 1992 special issue ofInternational Organization. Over the past twenty years, the idea has gained some traction in International Relations scholarship, but has not evolved much beyond its original conceptualisation. Much of the research on epistemic communities has been limited to single case studies in articles, rather than broader comparative works, and has focused narrowly on groups of scientists. As a result, it is often assumed, erroneously, that epistemic communities are only comprised of scientists, and that the utility of the concept for understanding International Relations is quite narrow. Consequently, an otherwise promising approach to transnational networks has become somewhat marginalised over the years. This article revisits the concept of epistemic communities twenty years later and proposes specific innovations to the framework. In an increasingly globalising world, transnational actors are becoming progressively more numerous and influential. Epistemic communities are certainly at the forefront of these trends, and a better understanding of how they form and operate can give us a clear demonstration of how knowledge translates into power.
Responsible reconstruction after war: meeting local needs for building peace
Authors: CUBITT CHRISTINE 
Published: April 2012

AbstractContemporary peacebuilding operations are often mandated to rebuild ‘collapsed’ or weak states and provide unique opportunities for internationals to exert far reaching influence in their reconstruction. The responsibility to help secure peaceful transformations and longer term stability is profound. This article explores the issue of efficacy and propriety in reconstruction programming and draws from field work in Sierra Leone – a rare example of ‘success’ for international partners in peacebuilding missions. The assertion is made that, despite the euphoria over the mission in Sierra Leone, the peacebuilding operations were more about the mechanics of statebuilding than the local politics of building peace, and that there was a distinct disconnect between the policy rhetoric and the policy practice. The argument is put that the pressing local concern of giving citizens a stake in government was not best served in the reconstruction project because the wider and more influential objectives of the peacebuilding mission were about meeting international goals not local aspirations. This reality has come at the cost of exploiting a unique opportunity for creative thinking about the kind of state structures which can better address the main challenges for sustainable peace facing post-war states like Sierra Leone.
Granitic batholiths: from pervasive and continuous melting in the lower crust to discontinuous and spaced plutonism in the upper crust
Authors: Vigneresse Jean Louis 
Published: April 2012

ABSTRACTThe generation of granitic magmas begins with melting in the lower crust, under active participation of the underlying mantle. Thermally driven, melting is a pervasive and continuous process that develops over a wide region. In contrast, the building of a granitic pluton is highly discontinuous in time and space. Several inputs of magma, sometimes with a different chemical compositions, are focused toward a region where they accumulate, forming a large pluton, often separated by some 50 km from an adjacent one. The switch from a continuous to a discontinuous process represents a fundamental point of magma generation. It gives place to the modified model m(M-SAE), in which the mantle (m) and Melting (M) are separated from the Segregation (S), Ascent (A) and Emplacement (E) modes. Discontinuities result from non-linear processes that develop during segregation and ascent of the magma. They rely on the non-linear rheology of partially molten rocks. Thresholds control the change from a solid-like to liquid-like behaviour of the magma. In between, the rheology exhibits sudden jumps between states. Because two phases continuously coexist (matrix and melt), strain is highly partitioned between them. This may induce highly discontinuous melt segregation, which needs both pure and simple shear to develop. Melt focusing is controlled by the viscosity contrast between the two phases. It gives rise to different compaction lengths depending on the region, a partially melting source or a nearly brittle crust, where it develops. Because ascent and emplacement are discontinuous in time, this allows the crust to relax, avoiding the room problem for a pluton intruding the upper crust. Intermediate magma chambers could develop with different temperature and magma composition. They could be the place of enhanced magma mixing. Finally, the stress conditions, which differ for each tectonic setting, influence the shape of the granitic body.
The economic potential of payments for ecosystem services in water conservation: a case study in the upper reaches of Shiyang River basin, northwest China
Authors: Tang Zeng , Shi Yulan , Nan Zhibiao , Xu Zhongmin 
Published: April 2012

AbstractIn this paper, we conduct an investigation to assess the economic potential of payments for ecosystem services to conserve water through the conversion of land under irrigation into rain-fed land in the upper reaches of the Shiyang River basin, located in northwest China. We use an approach developed by Antle and Valdivia (2006, Australian Journal of Agricultural and Resource Economics, 50: 1–15) to estimate the supply of water. The analysis shows that it is theoretically possible to reduce agricultural water consumption and subsequently increase the water supply, which would aid the prevention of environmental degradation in the middle and lower reaches of the Shiyang River basin. In addition to the conservation of water, considerable income would be generated by local farmers, which would help to alleviate poverty. Furthermore, the analysis also suggests that more complete data on ecosystem services rates, transaction costs and other related factors would be of value for achieving a more comprehensive assessment.