Homology and modular classes of Lie algebroids

For a Lie algebroid, divergences chosen in a classical way lead to a uniquely defined homology theory. They define also, in a natural way, modular classes of certain Lie algebroid morphisms. This approach, applied for the anchor map, recovers the concept of modular class due to S. Evans, J.-H. Lu, and A. Weinstein.Comment: 11 pages, AmSLaTeX, 3 typos correcte

Dynamics of reflection of ultracold atoms from a periodic 1D magnetic lattice potential

We report on an experimental study of the dynamics of the reflection of ultracold atoms from a periodic one-dimensional magnetic lattice potential. The magnetic lattice potential of period 10 \textmu m is generated by applying a uniform bias magnetic field to a microfabricated periodic structure on a silicon wafer coated with a multilayered TbGdFeCo/Cr magneto-optical film. The effective thickness of the magnetic film is about 960 nm. A detailed study of the profile of the reflected atoms as a function of externally induced periodic corrugation in the potential is described. The effect of angle of incidence is investigated in detail. The experimental observations are supported by numerical simulations.Comment: 15 pages, 11 figure

Skewness-Adjusted Bootstrap Confidence Intervals and Confidence Bands for Impulse Response Functions

This Article Investigates The Construction Of Skewness-Adjusted Confidence Intervals And Joint Confidence Bands For Impulse Response Functions From Vector Autoregressive Models. Three Different Implementations Of The Skewness Adjustment Are Investigated. The Methods Are Based On A Bootstrap Algorithm That Adjusts Mean And Skewness Of The Bootstrap Distribution Of The Autoregressive Coefficients Before The Impulse Response Functions Are Computed. Using Extensive Monte Carlo Simulations, The Methods Are Shown To Improve The Coverage Accuracy In Small And Medium Sized Samples And For Unit Root Processes For Both Known And Unknown Lag Orders

The eukaryotic leading and lagging strand DNA polymerases are loaded onto primer-ends via separate mechanisms but have comparable processivity in the presence of PCNA

Saccharomyces cerevisiae DNA polymerase δ (Pol δ) and DNA polymerase ε (Pol ε) are replicative DNA polymerases at the replication fork. Both enzymes are stimulated by PCNA, although to different levels. To understand why and to explore the interaction with PCNA, we compared Pol δ and Pol ε in physical interactions with PCNA and nucleic acids (with or without RPA), and in functional assays measuring activity and processivity. Using surface plasmon resonance technique, we show that Pol ε has a high affinity for DNA, but a low affinity for PCNA. In contrast, Pol δ has a low affinity for DNA and a high affinity for PCNA. The true processivity of Pol δ and Pol ε was measured for the first time in the presence of RPA, PCNA and RFC on single-stranded DNA. Remarkably, in the presence of PCNA, the processivity of Pol δ and Pol ε on RPA-coated DNA is comparable. Finally, more PCNA molecules were found on the template after it was replicated by Pol ε when compared to Pol δ. We conclude that Pol ε and Pol δ exhibit comparable processivity, but are loaded on the primer-end via different mechanisms

Effects of Medicare Payment Reform: Evidence from the Home Health Interim and Prospective Payment Systems

Medicare continues to implement payment reforms that shift reimbursement from fee-for-service towards episode-based payment, affecting average and marginal reimbursement. We contrast the effects of two reforms for home health agencies. The Home Health Interim Payment System in 1997 lowered both types of reimbursement; our conceptual model predicts a decline in the likelihood of use and costs, both of which we find. The Home Health Prospective Payment System in 2000 raised average but lowered marginal reimbursement with theoretically ambiguous effects; we find a modest increase in use and costs. We find little substantive effect of either policy on readmissions or mortality

New Evidence on the Green House Model of Nursing Home Care: Synthesis of Findings and Implications for Policy, Practice, and Research

OBJECTIVE: To synthesize new findings from the THRIVE Research Collaborative (The Research Initiative Valuing Eldercare) related to the Green House (GH) model of nursing home care and broadly consider their implications. DATA SOURCES: Interviews and observations conducted in GH and comparison homes, Minimum Data Set (MDS) assessments, Medicare data, and Online Survey, Certification and Reporting data. STUDY DESIGN: Critical integration and interpretation of findings based on primary data collected 2011-2014 in 28 GH homes (from 16 organizations), and 15 comparison nursing home units (from 8 organizations); and secondary data derived from 2005 to 2010 for 72 GH homes (from 15 organizations) and 223 comparison homes. PRINCIPAL FINDINGS: Implementation of the GH model is inconsistent, sometimes differing from design. Among residents of GH homes, adoption lowers hospital readmissions, three MDS measures of poor quality, and Part A/hospice Medicare expenditures. Some evidence suggests the model is associated with lower direct care staff turnover. CONCLUSIONS: Recommendations relate to assessing fidelity, monitoring quality, capitalizing opportunities to improve care, incorporating evidence-based practices, including primary care providers, supporting high-performance workforce practices, aligning Medicare financial incentives, promoting equity, informing broad culture change, and conducting future research

Eating habits associated with body weight gain in female university students : a UK-based study of Slimming World members

Purpose: To examine dietary habits, cooking skills, physical activity levels and perceived reasons for weight gain in relation to levels of body weight gain among university students in the UK. Design/methodology/approach: This study explored factors associated with body weight gain in a cross-sectional study of British university students who were actively trying to lose weight. University student members of a national commercial slimming programme completed an online survey about weight gain, eating habits, cooking abilities and physical activity levels. Non-parametric tests and regression analysis were employed to examine factors associated with weight gain. Findings: The dataset comprised 272 current students. The majority of students (67%) reported weight gain between 3.2 and 12.7 kg during university: 20.4% reported to have gained >12.7 kg. Students commonly attributed their weight gain to academic stress and nearly all identified with needing support to learn to cook on a budget. Students reporting greatest weight gain had most frequent consumption of ready meals & convenience foods, take-away & fast foods, and least frequent consumption of fruits & vegetables. Weight-stable students reported lowest consumption of alcohol and were most able to cook complex meals. Students who reported greatest weight gain reported lower physical activity levels. There were inter-correlations between cooking ability and lifestyle factors. In a multivariate model, low physical activity and frequent consumption of ready meals and convenience food independently predicted weight gain. Research limitations/implications: Prospective studies are needed to confirm these cross-sectional associations and to qualitatively explore how the university setting may contribute to the effects. Practical implications: Strategies to address students’ reliance on fast and convenience food, avoidance of fruit and vegetables, poor cooking confidence and low physical activity may benefit student health and well-being. Social implications: Originality/value: The study adds additional perspective to understanding student weight gain at university in that it focuses on a a body weight-conscious sub-group of the student population, as opposed to the general population of student

LONG JUMP MECHANICS – OLYMPIC VERSUS PARALYMPIC CHAMPION

In the last 20 years the long jump world record of athletes with an amputation of the lower extremities has improved by over two meters. However, there is no recent research on amputee long jumping and no information about amputee long jump kinetics. In this study the take-off step of an Olympic and a Paralympic champion were analyzed with regard to jumping mechanics. A 3D motion capturing system (Vicon) and a force plate (Kistler) were used to capture kinematic and kinetic data. Inverse dynamic calculations (Dynamicus, Alaska) revealed remarkable differences with respect to mechanical loading and motor solutions between the transtibial amputee and non-amputee long jumper. Mechanical constraints and material properties of the prosthesis might influence the kinematic chain of the amputee athlete and impose the need for an alternative motor solution

A Distance-Weighted Interaction Map Reveals a Previously Uncharacterized Layer of the Bacillus subtilis Spore Coat

SummaryBacillus subtilis spores are encased in a protein assembly called the spore coat that is made up of at least 70 different proteins. Conventional electron microscopy shows the coat to be organized into two distinct layers. Because the coat is about as wide as the theoretical limit of light microscopy, quantitatively measuring the localization of individual coat proteins within the coat is challenging. We used fusions of coat proteins to green fluorescent protein to map genetic dependencies for coat assembly and to define three independent subnetworks of coat proteins. To complement the genetic data, we measured coat protein localization at subpixel resolution and integrated these two data sets to produce a distance-weighted genetic interaction map. Using these data, we predict that the coat comprises at least four spatially distinct layers, including a previously uncharacterized glycoprotein outermost layer that we name the spore crust. We found that crust assembly depends on proteins we predicted to localize to the crust. The crust may be conserved in all Bacillus spores and may play critical functions in the environment