Using manipulated photographs to identify features of streetscapes that may encourage older adults to walk for transport

Experimental evidence of environmental features important for physical activity is challenging to procure in real world settings. The current study aimed to investigate the causal effects of environmental modifications on a photographed street\u27s appeal for older adults\u27 walking for transport. Secondly, we examined whether these effects differed according to gender, functional limitations, and current level of walking for transport. Thirdly, we examined whether different environmental modifications interacted with each other. Qualitative responses were also reported to gain deeper insight into the observed quantitative relationships. Two sets of 16 panoramic photographs of a streetscape were created, in which six environmental factors were manipulated (sidewalk evenness, traffic level, general upkeep, vegetation, separation from traffic, and benches). Sixty older adults sorted these photographs on appeal for walking for transport on a 7-point scale and reported qualitative information on the reasons for their rankings. Sidewalk evenness appeared to have the strongest influence on a street\u27s appeal for transport-related walking. The effect of sidewalk evenness was even stronger when the street\u27s overall upkeep was good and when traffic was absent. Absence of traffic, presence of vegetation, and separation from traffic also increased a street\u27s appeal for walking for transport. There were no moderating effects by gender or functional limitations. The presence of benches increased the streetscape\u27s appeal among participants who already walked for transport at least an hour/week. The protocols and methods used in the current study carry the potential to further our understanding of environment-PA relationships. Our findings indicated sidewalk evenness as the most important environmental factor influencing a street\u27s appeal for walking for transport among older adults. However, future research in larger samples and in real-life settings is needed to confirm current findings

Molecules in external fields: a semiclassical analysis

We undertake a semiclassical analysis of the spectral properties (modulations of photoabsorption spectra, energy level statistics) of a simple Rydberg molecule in static fields within the framework of Closed-Orbit/Periodic-Orbit theories. We conclude that in addition to the usual classically allowed orbits one must consider classically forbidden diffractive paths. Further, the molecule brings in a new type of 'inelastic' diffractive trajectory, different from the usual 'elastic' diffractive orbits encountered in previous studies of atomic and analogous systems such as billiards with point-scatterers. The relative importance of inelastic versus elastic diffraction is quantified by merging the usual Closed Orbit theory framework with molecular quantum defect theory.Comment: 4 pages, 3 figure

Remission, continuation and incidence of eating disorders during early pregnancy: a validation study in a population-based birth cohort

Background—The objective of this study was to validate previously published rates of remission, continuation, and incidence of broadly defined eating disorders during pregnancy. The previous rate modeling was done by our group (Bulik et al. 2007) and yielded participants halfway into recruitment of the planned 100,000 pregnancies in the Norwegian Mother and Child (MoBa) Cohort at the Norwegian Institute of Public Health. This study aimed to internally validate the findings with the completed cohort. Methods—77267 pregnant women enrolled at 17 weeks gestation between 2001 and 2009 were included. Participants were split into a “training” sample (n=41243) based on participants in the MoBa version 2 dataset of the original study and a “validation” sample (n=36024) comprising individuals in the MoBa version 5 dataset that were not in the original study (Bulik et al. 2007). Internal validation of all original rate models involved fitting a calibration model to compare model parameters between the “training” and “validation” samples as well as bootstrap estimates of bias in the entire version 5 dataset. Results—Remission, continuation, and incidence estimates from the “training” sample remained stable when evaluated via a split sample validation procedure. Pre-pregnancy prevalence estimates in the “validation” sample were 0.1% for anorexia nervosa, 1.0% for bulimia nervosa (BN), 3.3% for binge eating disorder (BED), and 0.1% for purging disorder (EDNOS-P). In early pregnancy, estimates were 0.2% for BN, 4.8% for BED, and <0.01% for EDNOS-P. Consistent with the original study, incident BN and EDNOS-P during pregnancy were rare. For BED, the adjusted incidence rate in the “validation” sample was 1.17 per 1000 person-weeks. The highest rates were for full or partial remission for BN and EDNOS-P, and continuation for BED. Conclusions—This study provides evidence of validity of previously estimated rates of remission, continuation, and incidence of eating disorders during pregnancy. Eating disorders during pregnancy were relatively common, occurring in nearly 1 in every 20 women, although almost all were cases of BED. Pregnancy was a window of remission from BN but a window of vulnerability for onset and continuation of BED. Training to detect the signs and symptoms of eating disorders by obstetricians/gynecologists and interventions to enhance pregnancy and neonatal outcomes warrant attention

On the Inequivalence of Weak-Localization and Coherent Backscattering

We define a current-conserving approximation for the local conductivity tensor of a disordered system which includes the effects of weak localization. Using this approximation we show that the weak localization effect in conductance is not obtained simply from the diagram corresponding to the coherent back-scattering peak observed in optical experiments. Other diagrams contribute to the effect at the same order and decrease its value. These diagrams appear to have no semiclassical analogues, a fact which may have implications for the semiclassical theory of chaotic systems. The effects of discrete symmetries on weak localization in disordered conductors is evaluated and and compared to results from chaotic scatterers.Comment: 24 pages revtex + 12 figures on request; hub.94.

Economic Impacts of Non-Native Forest Insects in the Continental United States

Reliable estimates of the impacts and costs of biological invasions are critical to developing credible management, trade and regulatory policies. Worldwide, forests and urban trees provide important ecosystem services as well as economic and social benefits, but are threatened by non-native insects. More than 450 non-native forest insects are established in the United States but estimates of broad-scale economic impacts associated with these species are largely unavailable. We developed a novel modeling approach that maximizes the use of available data, accounts for multiple sources of uncertainty, and provides cost estimates for three major feeding guilds of non-native forest insects. For each guild, we calculated the economic damages for five cost categories and we estimated the probability of future introductions of damaging pests. We found that costs are largely borne by homeowners and municipal governments. Wood- and phloem-boring insects are anticipated to cause the largest economic impacts by annually inducing nearly $1.7 billion in local government expenditures and approximately$830 million in lost residential property values. Given observations of new species, there is a 32% chance that another highly destructive borer species will invade the U.S. in the next 10 years. Our damage estimates provide a crucial but previously missing component of cost-benefit analyses to evaluate policies and management options intended to reduce species introductions. The modeling approach we developed is highly flexible and could be similarly employed to estimate damages in other countries or natural resource sectors

Genome-wide association scan meta-analysis identifies three Loci influencing adiposity and fat distribution.

To identify genetic loci influencing central obesity and fat distribution, we performed a meta-analysis of 16 genome-wide association studies (GWAS, N = 38,580) informative for adult waist circumference (WC) and waist-hip ratio (WHR). We selected 26 SNPs for follow-up, for which the evidence of association with measures of central adiposity (WC and/or WHR) was strong and disproportionate to that for overall adiposity or height. Follow-up studies in a maximum of 70,689 individuals identified two loci strongly associated with measures of central adiposity; these map near TFAP2B (WC, P = 1.9x10(-11)) and MSRA (WC, P = 8.9x10(-9)). A third locus, near LYPLAL1, was associated with WHR in women only (P = 2.6x10(-8)). The variants near TFAP2B appear to influence central adiposity through an effect on overall obesity/fat-mass, whereas LYPLAL1 displays a strong female-only association with fat distribution. By focusing on anthropometric measures of central obesity and fat distribution, we have identified three loci implicated in the regulation of human adiposity

Discovery of Sexual Dimorphisms in Metabolic and Genetic Biomarkers

Metabolomic profiling and the integration of whole-genome genetic association data has proven to be a powerful tool to comprehensively explore gene regulatory networks and to investigate the effects of genetic variation at the molecular level. Serum metabolite concentrations allow a direct readout of biological processes, and association of specific metabolomic signatures with complex diseases such as Alzheimer's disease and cardiovascular and metabolic disorders has been shown. There are well-known correlations between sex and the incidence, prevalence, age of onset, symptoms, and severity of a disease, as well as the reaction to drugs. However, most of the studies published so far did not consider the role of sexual dimorphism and did not analyse their data stratified by gender. This study investigated sex-specific differences of serum metabolite concentrations and their underlying genetic determination. For discovery and replication we used more than 3,300 independent individuals from KORA F3 and F4 with metabolite measurements of 131 metabolites, including amino acids, phosphatidylcholines, sphingomyelins, acylcarnitines, and C6-sugars. A linear regression approach revealed significant concentration differences between males and females for 102 out of 131 metabolites (p-values<3.8 x 10(-4); Bonferroni-corrected threshold). Sex-specific genome-wide association studies (GWAS) showed genome-wide significant differences in beta-estimates for SNPs in the CPS1 locus (carbamoyl-phosphate synthase 1, significance level: p<3.8 x 10(-10); Bonferroni-corrected threshold) for glycine. We showed that the metabolite profiles of males and females are significantly different and, furthermore, that specific genetic variants in metabolism-related genes depict sexual dimorphism. Our study provides new important insights into sex-specific differences of cell regulatory processes and underscores that studies should consider sex-specific effects in design and interpretation

ℏ\hbar corrections in semi-classical formula for smooth chaotic dynamics

The validity of semiclassical expansions in the power of $\hbar$ for the quantum Green's function have been extensively tested for billiards systems, but in the case of chaotic dynamics with smooth potential, even if formula are existing, a quantitative comparison is still missing. In this paper, extending the theory developed by Gaspard et al., Adv. Chem. Phys. XC 105 (1995), based on the classical Green's functions, we present an efficient method allowing the calculation of $\hbar$ corrections for the propagator, the quantum Green's function, and their traces. Especially, we show that the previously published expressions for $\hbar$ corrections to the traces are incomplete.Comment: 19 pages, 4 figures, to be published in Phys. Rev. E shortened version, corrected typo

A comparison of two cases of low-latitude thundersnow

http://solberg.snr.missouri.edu/gcc/Two cases of low-latitude snow with lightning are studied to determine their characteristics. Both cases had synoptic-scale origins, but also featured smaller-scale influences (e. g. orographic lift and elevated instability).The first event occurred in the Southern Hemisphere and was a late winter case that developed under the influence of underlying orography. Lightning was plentiful in that event (94 cloud-to-ground flashes in the region), but snow accumulations were not significant. Lightning flashes of negative polarity dominated this case, with a mean peak amplitude of -43.2 kA. The second event was a Northern Hemisphere case of elevated convection, with frontogenesis beneath an extended layer of potential instability. Appreciable lightning occurred with this event as well (706 cloud-to-ground flashes in the region), and snow accumulations were significant over a broad area. Lightning flashes of negative polarity dominated this case also, with a mean peak amplitude of -23.7 kA. Each of these events is worthy of further scrutiny, as studies of such storms do not appear often in the literature. Indeed, such warm, subtropical regions are often unprepared for the effects of just a little snow or ice accumulation. Future forecasters can anticipate better such anomalous events by looking for these broad features: 1) significant and well-defined synoptic-scale weather systems at low latitudes, 2) a strong baroclinic zone with a well-defined (≥60 ms-1) jet structure aloft, 3) cold air of appreciable depth and areal extent drawn much closer to the equator than is typical, and 4) a moist neutral to conditionally unstable layer above the frontal zone