Quantifying the effects of modelling choices on hospital efficiency measures: A meta-regression analysis

It has often been argued that the results of efficiency analyses in health care are influenced by the modelling choices made by the researchers involved. In this paper we use meta-regression analysis in an attempt to quantify the degree to which modelling factors influence efficiency estimates. The data set is derived from 253 estimated models reported in 95 empirical analyses of hospital efficiency in the 22-year period from 1987 to 2008. A meta-regression model is used to investigate the degree to which differences in mean efficiency estimates can be explained by factors such as: sample size; dimension (number of variables); parametric versus non-parametric method; returns to scale (RTS) assumptions; functional form; error distributional form; input versus output orientation; cost versus technical efficiency measure; and cross-sectional versus panel data. Sample size, dimension and RTS are found to have statistically significant effects at the 1% level. Sample size has a negative (and diminishing) effect on efficiency; dimension has a positive (and diminishing) effect; while the imposition of constant returns to scale has a negative effect. These results can be used in improving the policy relevance of the empirical results produced by hospital efficiency studies.

Agricultural Land Distribution in Vietnam: Emerging Issues and Policy Implications

This paper examines the current distribution of the agricultural land, the issues causing landlessness in Vietnam, assesses present governmental policies and methods and presents key options. The paper relies on the Vietnam Living Household Standard Survey (VHLSS) that were conducted by the General Statistics Office in 2002 and 2004, and qualitative evidence from other studies. It is found that land inequality is increasing. Poor households have small areas of agricultural land and aquacultural water surface, and their lands are also of low quality. Landless poor are dependent on low income and unstable income from labouring in agricultural production. Policies to assist the landless have had limited impact.Land distribution, landless, poverty, Vietnam, Asia

From Mendelian inheritance to molecular genomics: a brief appreciation of genetics

Biology is one of many sciences advancing society and the human conquest for knowledge. Its transition from speculation to lifestyle has been a turbulent ride for centuries, but nevertheless, implications for health improvement has only allowed the field to be advocated by more and more people beyond the professions. Revolutionary findings in genetics increased rapidly for either the advancement of knowledge or its promise for medicine, and while its celebration is heard in academia and achievements like Nobel Prizes, many of the details and reasons for these celebrations are not fully understood. In this mini retrospect, I reflect on a fraction of breakthroughs in genetics as a valuable biological tool and the reasons for why there is great appreciation and anticipation in the field today—and tomorrow

Self-Controlled Feedback and Activity Level in Learning a Simple Movement Skill

The purpose of this study was to determine if active and sedentary individuals differed in terms the effects of self-controlled feedback on the learning of a movement skill. The task consisted of a blindfolded beanbag toss using the non-preferred arm. Participants were prescreened according to their physical activity level using the International Physical Activity Questionnaire (Craig et al., 2003). An equal number of active (A) and sedentary (S) participants were assigned to self-control (SC) and yoked (Y) feedback conditions, creating four groups: Self-Control Active; Self-Control Sedentary; Yoked Active; and Yoked Sedentary. SC condition participants were provided feedback whenever they requested it, while Y condition participants received feedback according to the schedule created by a SC counterpart to whom they were yoked. The SC condition was more accurate than the Y condition during acquisition and transfer phases. The A condition was more accurate than the S condition during all phases of the experiment. Results of a post-experimental questionnaire indicated that participants in the SC condition asked for feedback mostly after what they perceived to be “good” trials. Participants in the Y condition indicated that they would have preferred to receive feedback after “good” trials. This study provided further support for the advantages of self-controlled feedback when learning motor skills, additionally showing benefits for both active and sedentary individuals. In addition, the results suggested that the provision of experimenter-controlled feedback (i.e., in the Y condition) to sedentary learners degraded immediate performance. While this effect was not present during assessment of learning, it may have implications regarding the motivation of sedentary individuals to engage in practice when learning movement skills

Mechanisms for the maintenance and eventual degradation of neurofilament proteins in the distal segments of severed goldfish Mauthner axons

Cellular mechanisms that might affect the degradation of neurofilament proteins (NFPs) were examined in the distal segments of severed goldfish Mauthner axons (M-axons), which do not degenerate for more than 2 months after severance. Calpain levels, as determined by reactivity to a polyclonal antibody, remained constant for 80 d postseverance in distal segments of M-axons and then declined from 80 to 85 d postseverance. Calpain activity in rat brain, as determined by a spectrophotometric assay, was much higher than calpain activity in control and severed goldfish brain, spinal cord, muscle, or M-axons. Calpain activity was extremely low in M-axons compared with that in all other tissues and remained low for up to 80 d postseverance in distal segments of M-axons. Phosphorylated NFPs, as determined by Stains-All treatment of SDS gels, were maintained for up to 72 d postseverance and then decreased noticeably at 75 d postseverance when NFP breakdown products appeared on silver-stained gels. By 85 d postseverance, phosphorylated NFPs no longer were detected, and NFP breakdown products were the most prominent bands on silver-stained gels. These results suggest that the distal segments of M-axons survive for months after severance, because NFPs are maintained in a phosphorylated state that stabilizes and protects NFPs from degradation by low levels of calpain activity in the M-axon; the distal segments of severed M-axons degenerate eventually when NFPs no longer are maintained in a phosphorylated state and become susceptible to degradation, possibly by low levels of calpain activity in the M-axon.This work was supported by an Advanced Technology Project Grant to G.D.B.Neuroscienc

On the mass aspect function and positive energy theorems for asymptotically hyperbolic manifolds

We prove positivity of energy for a class of asymptotically locally hyperbolic manifolds in dimensions $4\le n \le 7$. The result is established by first proving deformation-of-mass-aspect theorems in dimensions $n\ge 4$. Our positivity results extend to the case $n = 3$ when more stringent conditions are imposed.Comment: trivial typos correcte

Indirect Searches for Dark Photon-Photon Tridents in Celestial Objects

We model and constrain the unique indirect detection signature produced by dark matter particles that annihilate through a $U(1)$ gauge symmetry into dark photons that subsequently decay into three-photon final states. We focus on scenarios where the dark photon is long-lived, and show that $\gamma$-ray probes of celestial objects can set strong constraints on the dark matter/baryon scattering cross section that in many cases surpass the power of current direct detection constraints, and in some cases even peer into the neutrino fog.Comment: 12 pages, 7 figures (8 sub-figures), 3 table

Gut microbiota of migrating wild rabbit fish (Siganus guttatus) larvae have low spatial and temporal variability

We investigated the gut microbiota of rabbit fish larvae at three locations in Vietnam (ThuanAn-northern, QuangNam-intermediate, BinhDinh-southern sampling site) over a three-year period. In the wild, the first food for rabbit fish larvae remains unknown, while the juveniles and adults are herbivores, forming schools near the coasts, lagoons, and river mouths, and feeding mainly on filamentous algae. This is the first study on the gut microbiota of the wild fish larvae and with a large number of individuals analyzed spatially and temporally. The Clostridiales order was the most predominant in the gut, and location-by-location alpha diversity showed significant differences in Chao-1, Hill number 1, and evenness. Analysis of beta diversity indicated that the location, not year, had an effect on the composition of the microbiota. In 2014, the gut microbiota of fish from QuangNam was different from that in BinhDinh; in 2015, the gut microbiota was different for all locations; and, in 2016, the gut microbiota in ThuanAn was different from that in the other locations. There was a time-dependent trend in the north-south axis for the gut microbiota, which is considered to be tentative awaiting larger datasets. We found limited variation in the gut microbiota geographically and in time and strong indications for a core microbiome. Five and fifteen OTUs were found in 100 and 99% of the individuals, respectively. This suggests that at this life stage the gut microbiota is under strong selection due to a combination of fish-microbe and microbe-microbe interactions