bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basin Modelling of Temperature and Heat Flow Distributions and Permafrost Evolution, Urengoy and Kuyumbinskaya Areas, Siberia
Authors: Galushkin Yu. I. , Sitar K. А. , Frolov S. V. 
Published: August 2013

ABSTRACTThe thermal history and permafrost evolution in the Urengoy area of the West Siberian basin and in the Kuyumbinskaya area of the Siberian platform during the Pliocene‐Quaternary were reconstructed numerically in a forward model from 3.4 Ma using the software package FROST, part of the basin modelling system GALO. Calculations suggest that variations in rock composition with depth strongly influenced permafrost evolution. Rock temperatures decreased by 15–20°C within the upper 1500 m of the sedimentary sequence because of climate cooling in the Pliocene‐Holocene. The effect of cooling is greater in the Kuyumbinskaya area, which has a thinner sedimentary cover, than in the more northern Urengoy area. The model estimates permafrost depth and the stability zone of methane gas hydrate. An increase in salt content in porewater from 1 to 30 g/l lowers the melting temperature of ice by 2°С and decreases permafrost thickness by almost 100 m. The change in shape of the unfrozen water curve W(T), dependent upon the lithological composition of sedimentary rocks, strongly influences the numerical estimations of permafrost depth. The modelling demonstrates that permafrost thickness and temperature and heat flow distributions with depth in the basins calculated with climate variations of the last 50 ka differ significantly from the more accurate values obtained with climate variations during the last 200 ka, 1 Ma or 3.4 Ma. Copyright © 2013 John Wiley & Sons, Ltd.
Exploring the Visuospatial Challenge of Learning About Day and Night and the Sun's Path
Authors: HEYWOOD DAVID , PARKER JOAN , ROWLANDS MARK 
Published: August 2013

ABSTRACTThe role of visualization and model‐based reasoning has become increasingly significant in science education across a range of contexts. It is generally recognized that supporting learning in developing causal explanations for observed astronomical events presents considerable pedagogic challenge. Understanding the Sun's apparent movement across the sky requires a sophisticated interpretation of visuospatial relations. This study explores how preservice teachers employ models in reasoning about this phenomenon. It adopts a research methodology that attempts to capture the fine detail of learning using a range of strategies to determine student teachers’ use of models in visuospatial reasoning. This included individual learners documenting their responses during taught sessions as part of the process of capturing their personal perceptions. Student reflections on their own learning were subsequently discussed during follow‐up audiotaped interviews. The findings revealed four different models of visuospatial reasoning used by the student teachers and highlighted subtle differences between individuals. The ways participants used these to make sense of the phenomenon and how this contributes to our understanding of model‐based reasoning in basic astronomy are discussed. © 2013 Wiley Periodicals, Inc. Sci Ed 97:772–796, 2013
Encouraging Entrepreneurship: Microfinance, Knowledge Support, and the Costs of Operating in Institutional Voids
Authors: Chakrabarty Subrata , Bass A. Erin 
Published: August 2013

AbstractThis study focuses on the supplemented strategies of microfinance institutions (MFIs), in which the MFI offers nonfinancial services, such as entrepreneurship related knowledge, in addition to financial services to impoverished borrowers at the bottom of the pyramid (BoP). We examine two contextual factors–foreign direct investment (FDI) and loan defaults–to better understand the relationship between providing knowledge support to encourage entrepreneurship and costs of operating at the BoP for MFIs. In contexts where FDI is low and loan defaults are high, providing knowledge support to encourage entrepreneurship aggravates the MFI's costs of operating at the BoP. However, in contexts where FDI is high and loan defaults are low, providing knowledge support to encourage entrepreneurship among impoverished borrowers does not aggravate the MFI's costs of operating at the BoP. Hence, in emerging markets where governments welcome FDI and curb loan defaults, MFIs can viably support entrepreneurship among the poor. © 2013 Wiley Periodicals, Inc.
Molecular Structure and Real‐Space Bonding Descriptors (AIM, ELI‐D) of Phenyl(triphenylstannyl)telluride
Authors: Beckmann Jens , Heinrich Darina , Mebs Stefan 
Published: August 2013

Abstract The previously known phenyl(triphenylstannyl)telluride, PhTeSnPh3, was prepared by the reaction of triphenyltin chloride, Ph3SnCl, with sodium phenyltellurolate, Na(TePh), in liquid ammonia. The molecular structure established by X‐ray crystallography and by geometry optimization at the DFT/B3PW91/TZ level of theory was used for calculations of real‐space bonding descriptors derived from an atoms‐in‐molecules (AIM) analysis of the theoretically calculated electron density. In addition, the electron localizability indicator (ELI‐D) was derived from the corresponding pair density and the Raub‐Jansen‐Index (RJI) was determined.
Living with an inborn error of metabolism detected by newborn screening—Parents’ perspectives on child development and impact on family life
Authors: Gramer Gwendolyn , Haege Gisela , Glahn Esther M. , Hoffmann Georg F. , Lindner Martin , Burgard Peter 
Published: August 2013

AbstractBackgroundNewborn screening for inborn errors of metabolism is regarded as highly successful by health professionals. Little is known about parents’ perspectives on child development and social impact on families.MethodsParents of 187 patients with metabolic disorders detected by newborn screening rated child development, perceived burdens on child and family, and future expectations on a questionnaire with standardized answers. Parental ratings were compared with standardized psychometric test results. Regression analysis was performed to identify factors associated with extent of perceived burden.ResultsIn 26.2 % of patients, parents perceived delays in global development and/or specific developmental domains (physical, social, intellectual, language). Parents expected normal future development in 95.7 %, and an independent adult life for their child in 94.6 %. Comparison with psychometric test results showed that parents of children with cognitive impairments tended to overrate their child's abilities. Mild/medium burden posed on the family (child) by the metabolic disorder was stated by 56.1 % (48.9 %) of parents, severe/very severe burden by 19.3 % (8.6 %). One third of families reported financial burden due to the metabolic disorder. Dietary treatment and diagnoses with risk for metabolic decompensation despite treatment were associated with higher perceived burden for the family. Disorders rated as potentially very burdensome by experts were not rated accordingly by parents, demonstrating different perspectives of professionals and parents.ConclusionAlthough newborn screening leads to favourable physical and cognitive outcome, living with a metabolic disorder may cause considerable stress on patients and families, emphasizing the need for comprehensive multidisciplinary care including psychological and social support.
Modern Vegetational Distribution and Pollen Dispersal Study within Gangotri Glacier Valley, Garhwal Himalaya
Authors: Ranhotra Parminder S. , Bhattacharyya Amalava 
Published: August 2013

Abstract
Modern pollen-vegetation relationship has been analyzed in respect to vegetational distribution and pollen dispersal from sub-alpine and alpine ecological regimes within the higher reaches of the Gangotri glacier valley. The results in general cope with the local ecological conditions of the sites within the valley. Above the tree line limits, the pollen frequency of arboreal taxa is found lower than those of non-arboreal taxa. In contrast the pine-birch forest area at Chirbasa represented the frequency of arboreal pollen (AP) more than that of non-arboreal pollen (NAP) due to over representation of Pinus wallichiana (conifer). Pollen grains of extra-local arboreal elements, mostly conifers have also been recorded here with fair amount of temperate broad-leaved arboreal taxa viz. Quercus, Alnus, Corylus, Carpinus, Ulmus, Juglans etc. that have been transported by the upthermic winds from their growing limits at lower altitudes to the study sites at higher altitudes. Non-arboreal taxa viz. marshy/aquatic, steppe and of other herbaceaous taxa, represents the existing ecological regimes of their respective sites within the valley. Differential pollen preservation has been observed between the moss cushion and sediment samples from the same site that may be due to the direct exposure of moss cushions to air, thus showing more concentration of wind pollinated pollen-spores as compared to surface sediments.
Usefulness of Adaptive Filtering for Improved Digital Elevation Model Generation
Authors: Bhattacharya Atanu , Arora Manoj K. , Sharma Mukat L. 
Published: August 2013

Abstract
The Digital Elevation Models (DEMs), which represent the variation of elevation in a terrain at spatial level, are an important source of input to a variety of applications for deriving a number of terrain parameters such as relative relief, slope, aspect direction etc. In recent years, Synthetic Aperture Radar Interferometry has been viewed as a powerful approach to derive quality DEMs from a pair of SAR images. Despite the interferometric technique is often limited by several de-correlations several researchers demonstrate its effectiveness in topographic mapping. The DEM accuracy is strongly influenced by the effectiveness of the phase unwrapping technique. In this study an effective adaptive filtering approach has been used to reduce the phase noise due to de-correlation and in improving the accuracy of phase unwrapping. Two well known phase unwrapping approaches such as branch cut and minimum cost flow network have been used. Interferometric data from ASAR sensor onboard ENVISAT satellite have been used. A highly undulated terrain condition near Dehradun city situated in Uttarakhand state of India was selected to investigate the performance of this adaptive filtering approach. The RMS error between the InSAR derived elevations and the map derived elevations was obtained as 7.2 m using adaptive filter. However, elevation map of the study area could not be generated due to high de-correlation effect without the use of adaptive filter. This result clearly demonstrates the effectiveness of adaptive filtering approach for generation of DEM at meter level accuracy, which is sufficient for many engineering applications.
Exploration of 100 commonly used drugs and supplements on cognition in older adults
Authors: Obermann Karen R. , Morris John C. , Roe Catherine M. 
Published: August 2013

AbstractBackgroundThere are conflicting reports and a lack of evidence‐based data regarding effects of medications on cognition in cognitively normal older adults. We explored whether use of 100 common medications taken by older adults is associated with longitudinal cognitive performance.MethodsA longitudinal observational cohort was used with analysis of data collected from September 2005 through May 2011 and maintained in the National Alzheimer's Coordinating Center (NACC) Uniform Data Set. Participants were aged 50 years or older and cognitively normal (N = 4414). Composite scores were constructed from 10 psychometric tests. Scores for each participant reflecting change in the psychometric composite score from the baseline clinical assessment to the next assessment were calculated. General linear models were used to test whether the mean composite change score differed for participants who reported starting, stopping, continuing, or not taking each of the 100 most frequently used medications in the NACC sample.ResultsThe average time between assessments was 1.2 years (SD = 0.42). Nine medications showed a difference (P < .05) across the four participant groups in mean psychometric change scores from the first to the second assessment. Medications associated with improved psychometric performance were naproxen, calcium‐vitamin D, ferrous sulfate, potassium chloride, flax, and sertraline. Medications associated with declining psychometric performance were bupropion, oxybutynin, and furosemide.ConclusionsReported use of common medications is associated with cognitive performance in older adults, but studies are needed to investigate the mechanisms underlying these effects.
Blood pressure variability and risk of dementia in an elderly cohort, the Three‐City Study
Authors: Alpérovitch Annick , Blachier Martin , Soumaré Aïcha , Ritchie Karen , Dartigues Jean‐François , Richard‐Harston Sandrine , Tzourio Christophe 
Published: August 2013

AbstractBackgroundThe relationship between blood pressure and dementia is incompletely understood in elderly individuals. Blood pressure variability may have a role in the risk of dementia.MethodsThis investigation was a cohort study of 6506 elderly individuals followed‐up for 8 years (1999–2001 through 2008) with assessments at years 2, 4, and 7–8. Blood pressure was measured by electronic devices at baseline and at 2‐ and 4‐year follow‐up examinations. Cox proportional hazard models adjusted for potential confounders were used to estimate the risk of incident dementia according to blood pressure (means and coefficients of variation of the three measures).ResultsDuring the 40,151 person‐years of follow‐up 474 participants developed dementia. We observed no association between mean blood pressure and risk of dementia. In contrast, an increase of 1 standard deviation in the coefficient of variation of blood pressure was associated with a 10% increased risk of dementia. Analysis by deciles of the coefficient of variation showed that the higher the variability, the higher the risk of dementia (P < .02 for trend). In the fully adjusted Cox model, the risk of dementia for those in the highest decile of the coefficient of variation of systolic blood pressure was 1.77 (1.17–2.69) compared with the lowest decile.ConclusionsIn this cohort study, variability of blood pressure during follow‐up was associated with an increased risk of incident dementia, whereas mean blood pressure was not. Limitation of blood pressure fluctuation may be an important target to preserve cognitive function in the elderly.
Use of an Emergency Medical Pictorial Communication Book During Simulated Disaster Conditions
Authors: Behar Solomon , Benson II Richard , Kurzweil Ami , Azen Colleen , Nager Alan L. 
Published: August 2013

AbstractDuring disasters, the needs of victims outstrip available resources. Rapid assessment of patients must be performed; however, language barriers can be an impediment to efficient patient assessment, especially if interpreter resources are limited. Dependency on interpretive services requiring technology such a telephones, cell phones, and video conferencing may be inefficient, as they may be unavailable during disaster conditions. A low-tech, portable tool that aids in communication with non-English speakers would be beneficial. The medical emergency communication (MEC) book, developed at Children's Hospital Los Angeles, has the potential to be a useful tool in this capacity.The goal of this pilot study was to compare the accuracy of a newly developed disaster-focused medical history obtained from Spanish-speaking patients or caregivers using the MEC book, compared to a control group with whom no book was used. Our hypothesis was that use of the MEC book improves accuracy of medical history taking between English-only speaking health care workers and Spanish-speaking patients better than a monolingual clinician trying to take a medical history without it. We anticipated a higher overall score in the group of subjects whose histories were taken using the MEC book than in the control group. Patient satisfaction with the MEC book also was measured. (Disaster Med Public Health Preparedness. 2013;0:1-6)
Induced diffusion of tracers in a bacterial suspension: theory and experiments
Authors: Miño G. L. , Dunstan J. , Rousselet A. , Clément E. , Soto R. 
Published: August 2013

AbstractThe induced diffusion of tracers in a bacterial suspension is studied theoretically and experimentally at low bacterial concentrations. Considering the swimmer–tracer hydrodynamic interactions at low Reynolds number and using a kinetic theory approach, it is shown that the induced diffusion coefficient is proportional to the swimmer concentration, their mean velocity and a coefficient$\beta $, as observed experimentally. This paper shows that$\beta $increases as a result of the interaction with solid surfaces. The coefficient$\beta $scales as the tracer–swimmer cross-section times the mean square displacement produced by single scattering events, which depends on the swimmer propulsion forces. Considering simple swimmer models (acting on the fluid as two monopoles or as a force dipole), it is shown that$\beta $increases for decreasing swimming efficiencies. Close to solid surfaces, the swimming efficiency degrades and, consequently, the induced diffusion increases. Experiments on wild-typeEscherichia coliin a Hele-Shaw cell, under buoyant conditions, are performed to measure the induced diffusion on tracers near surfaces. The modification of the suspension pH varies the swimmers’ velocity over a wide range, allowing the$\beta $coefficient to be extracted with precision. It is found that solid surfaces modify the induced diffusion: decreasing the confinement height of the cell,$\beta $increases by a factor of 4. The theoretical model reproduces this increase, although there are quantitative differences, probably attributed to the simplicity of the swimmer models and to the estimates for the parameters that modelE. coli.
Meridional trapping and zonal propagation of inertial waves in a rotating fluid shell
Authors: Rabitti Anna , Maas Leo R. M. 
Published: August 2013

AbstractInertial waves propagate in homogeneous rotating fluids, and constitute a challenging and simplified case study for the broader class of inertio-gravity waves, present in all geophysical and astrophysical media, and responsible for energetically costly processes such as diapycnal and angular momentum mixing. However, a complete analytical description and understanding of internal waves in arbitrarily shaped enclosed domains, such as the ocean or a planet liquid core, is still missing. In this work, the inviscid, linear inertial wave field is investigated by means of three-dimensional ray tracing in spherical shell domains, having in mind possible oceanographic applications. Rays are here classically interpreted as representative of energy paths, but in contrast to previous studies, they are now launched with a non-zero initial zonal component allowing for a more realistic, localized forcing and the development of azimuthal inhomogeneities. We find that meridional planes generally act in the shell geometry as attractors for ray trajectories. In addition, the existence of trajectories that are not subject to meridional trapping is here observed for the first time. Their dynamics was not captured by the previous purely meridional studies and unveils a new class of possible solutions for inertial motion in the spherical shell. Both observed behaviours shed some new light on possible mechanisms of energy localization, a key process that still deserves further investigation in our ocean, as well as in other stratified, rotating media.
On the nonlinear destabilization of stably stratified shear flow
Authors: Mkhinini Nadia , Dubos Thomas , Drobinski Philippe 
Published: August 2013

AbstractA weakly nonlinear analysis of the bifurcation of the stratified Ekman boundary-layer flow near a critical bulk Richardson number is conducted and compared to a similar analysis of a continuously stratified parallel shear flow subject to Kelvin–Helmholtz instability. Previous work based on asymptotic expansions and predicting supercritical bifurcation at Prandtl number $Pr\lt 1$ and subcritical bifurcation at $Pr\gt 1$ for the parallel base flow is confirmed numerically and through fully nonlinear temporal simulations. When applied to the non-parallel Ekman flow, weakly nonlinear analysis and fully nonlinear calculations confirm that the nature of the bifurcation is dominantly controlled by $Pr$, although a sharp threshold at $Pr= 1$ is not found. In both flows the underlying physical mechanism is that the mean flow adjusts so as to induce a viscous (respectively diffusive) flux of momentum (respectively buoyancy) that balances the vertical flux induced by the developing instability, leading to a weakening of the mean shear and mean stratification. The competition between the former nonlinear feedback, which tends to be stabilizing, and the latter, which is destabilizing and strongly amplified as $Pr$ increases, determines the supercritical or subcritical character of the bifurcation. That essentially the same competition is at play in both the parallel shear flow and the Ekman flow suggests that the underlying mechanism is valid for complex, non-parallel stratified shear flows.
SOME REMARKS ON THE PIGOLA–RIGOLI–SETTI VERSION OF THE OMORI–YAU MAXIMUM PRINCIPLE
Authors: BARRETO ALEXANDRE PAIVA , FONTENELE FRANCISCO 
Published: August 2013

AbstractWe prove that the hypotheses in the Pigola–Rigoli–Setti version of the Omori–Yau maximum principle are logically equivalent to the assumption that the manifold carries a${C}^{2} $proper function whose gradient and Hessian (Laplacian) are bounded. In particular, this result extends the scope of the original Omori–Yau principle, formulated in terms of lower bounds for curvature.
Validation of a food quantification picture book targeting children of 0–10 years of age for pan-European and national dietary surveys
Authors: Trolle Ellen , Vandevijvere Stefanie , Ruprich Jiří , Ege Majken , Dofková Marcela , de Boer Evelien , Ocké Marga 
Published: August 2013

The aim of the present study was to validate thirty-eight picture series of six pictures each developed within the PANCAKE (Pilot study for the Assessment of Nutrient intake and food Consumption Among Kids in Europe) project for portion size estimation of foods consumed by infants, toddlers and children for future pan-European and national dietary surveys. Identical validation sessions were conducted in three European countries. In each country, forty-five foods were evaluated; thirty-eight foods were the same as the depicted foods, and seven foods were different, but meant to be quantified by the use of one of the thirty-eight picture series. Each single picture within a picture series was evaluated six times by means of predefined portions. Therefore, thirty-six pre-weighed portions of each food were evaluated by convenience samples of parents having children aged from 3 months to 10 years. The percentages of participants choosing the correct picture, the picture adjacent to the correct picture or a distant picture were calculated, and the performance of individual pictures within the series was assessed. For twenty foods, the picture series performed acceptably (mean difference between the estimated portion number and the served portion number less than 0·4 (sd< 1·1)). In addition, twelve foods were rated acceptable after adjustment for density differences. Some other series became acceptable after analyses at the country level. In conclusion, all picture series were acceptable for inclusion in the PANCAKE picture book. However, the picture series of baby food, salads and cakes either can only be used for foods that are very similar to those depicted or need to be substituted by another quantification tool.