The Accuracy and Validity of Self-Reported Throwing Loads and the Characteristics of Throws by Elite Cricket Players in Australia

Objectives: To determine the relationship between elite cricket player’s self-reported and independently observed throwing volume. Examine whether sex, playing position, or time to upload self-reported data post training influences the accuracy of self-reported throwing loads. Describe the type and number of throws performed during elite cricket training, and identify characteristics such as type, distance and accuracy of throws. Design: Cross-sectional study. Methods: A total of eight female and 18 male professional cricket players participated in the study. Overarm throws from 12 training sessions during the 2020-21 cricket year were observed. Player self-reported throwing volume data were retrieved post training, with the time difference between session completion and self-reported data upload recorded. Observations on throwing type (warm-up, drill throw), distance (± 30 meters) and accuracy (hit or miss target) of throws was noted. Correlation and agreement was assessed using a Spearman’s Rank Correlation Coefficient and a Bland-Altman plot of agreement. Two, Independent-Samples Kruskal-Wallis tests were used to investigate if playing position and sex had an influence on absolute magnitude of error of reporting. Results: A moderate positive correlation was found between self-reported and observed throwing loads (rho = 0.65), however only 22% of players reported values within a clinically acceptable error of 10%. Players reported a mean absolute magnitude of error of 11.2 (9.8) throws and a mean magnitude of error of 24.8% (SD 16.0%). Sex did not influence reporting accuracy (p = 0.414). Playing position had a statistically significant (p = 0.031), though not clinically meaningful, relationship. Females uploaded self-reported data the day of training, whereas most males reported the day following. Reporting the day of training, or the day following training did not appear to result in poorer self-reported throwing load accuracy. Conclusions: The findings of this study question the validity of player self-reported throwing load as most players recorded in excess of 10% error. Sport support staff and players should consider whether the current accuracy of self-reported throwing load justifies its collection and use in the high-performance environment

Prompt Electromagnetic Transients from Binary Black Hole Mergers

Binary black hole (BBH) mergers provide a prime source for current and future interferometric GW observatories. Massive BBH mergers may often take place in plasma-rich environments, leading to the exciting possibility of a concurrent electromagnetic (EM) signal observable by traditional astronomical facilities. However, many critical questions about the generation of such counterparts remain unanswered. We explore mechanisms that may drive EM counterparts with magnetohydrodynamic simulations treating a range of scenarios involving equal-mass black-hole binaries immersed in an initially homogeneous fluid with uniform, orbitally aligned magnetic fields. We find that the time development of Poynting luminosity, which may drive jet-like emissions, is relatively insensitive to aspects of the initial configuration. In particular, over a significant range of initial values, the central magnetic field strength is effectively regulated by the gas flow to yield a Poynting luminosity of $10^{45}-10^{46} \rho_{-13} M_8^2 \, {\rm erg}\,{\rm s}^{-1}$, with BBH mass scaled to $M_8 \equiv M/(10^8 M_{\odot})$ and ambient density $\rho_{-13} \equiv \rho/(10^{-13} \, {\rm g} \, {\rm cm}^{-3})$. We also calculate the direct plasma synchrotron emissions processed through geodesic ray-tracing. Despite lensing effects and dynamics, we find the observed synchrotron flux varies little leading up to merger.Comment: 22 pages, 21 figures; additional reference + clarifying text added to match published versio

Human resources for control of tuberculosis and HIV-associated tuberculosis.

The global targets for tuberculosis (TB) control were postponed from 2000 to 2005, but on current evidence a further postponement may be necessary. Of the constraints preventing these targets being met, the primary one appears to be the lack of adequately trained and qualified staff. This paper outlines: 1) the human resources and skills for global TB and human immunodeficiency virus (HIV) TB control, including the human resources for implementing the DOTS strategy, the additional human resources for implementing joint HIV-TB control strategies and what is known about human resource gaps at global level; 2) the attempts to quantify human resource gaps by focusing on a small country in sub-Saharan Africa, Malawi; and 3) the main constraints to human resources and their possible solutions, under six main headings: human resource planning; production of human resources; distribution of the work-force; motivation and staff retention; quality of existing staff; and the effect of HIV/AIDS. We recommend an urgent shift in thinking about the human resource paradigm, and exhort international policy makers and the donor community to make a concerted effort to bridge the current gaps by investing for real change

Floquet Chern Insulators of Light

Achieving topologically-protected robust transport in optical systems has recently been of great interest. Most topological photonic structures can be understood by solving the eigenvalue problem of Maxwell's equations for a static linear system. Here, we extend topological phases into dynamically driven nonlinear systems and achieve a Floquet Chern insulator of light in nonlinear photonic crystals (PhCs). Specifically, we start by presenting the Floquet eigenvalue problem in driven two-dimensional PhCs and show it is necessarily non-Hermitian. We then define topological invariants associated with Floquet bands using non-Hermitian topological band theory, and show that topological band gaps with non-zero Chern number can be opened by breaking time-reversal symmetry through the driving field. Furthermore, we show that topological phase transitions between Floquet Chern insulators and normal insulators occur at synthetic Weyl points in a three-dimensional parameter space consisting of two momenta and the driving frequency. Finally, we numerically demonstrate the existence of chiral edge states at the interfaces between a Floquet Chern insulator and normal insulators, where the transport is non-reciprocal and uni-directional. Our work paves the way to further exploring topological phases in driven nonlinear optical systems and their optoelectronic applications, and our method of inducing Floquet topological phases is also applicable to other wave systems, such as phonons, excitons, and polaritons

Improved Moving Puncture Gauge Conditions for Compact Binary Evolutions

Robust gauge conditions are critically important to the stability and accuracy of numerical relativity (NR) simulations involving compact objects. Most of the NR community use the highly robust---though decade-old---moving-puncture (MP) gauge conditions for such simulations. It has been argued that in binary black hole (BBH) evolutions adopting this gauge, noise generated near adaptive-mesh-refinement (AMR) boundaries does not converge away cleanly with increasing resolution, severely limiting gravitational waveform accuracy at computationally feasible resolutions. We link this noise to a sharp (short-wavelength), initial outgoing gauge wave crossing into progressively lower resolution AMR grids, and present improvements to the standard MP gauge conditions that focus on stretching, smoothing, and more rapidly settling this outgoing wave. Our best gauge choice greatly reduces gravitational waveform noise during inspiral, yielding less fluctuation in convergence order and $\sim 40$ lower waveform phase and amplitude errors at typical resolutions. Noise in other physical quantities of interest is also reduced, and constraint violations drop by more than an order of magnitude. We expect these improvements will carry over to simulations of all types of compact binary systems, as well as other $N$+1 formulations of gravity for which MP-like gauge conditions can be chosen.Comment: 25 pages, 16 figures, 2 tables. Matches published versio

Thymic egress: S1P of 1000

Recent studies have begun to illuminate the mechanism of T-cell export from the thymus, with the identification of a required lysophospholipid receptor, two upstream transcription factors, and several downstream regulators of cytoskeleton dynamics. This work has generated immediate translational impact, aiding the design of immunosuppressant drugs and the identification of a novel form of human immunodeficiency

The Determinants of Micro, Small and Medium Enterprises’ (MSMEs) Performance in Nigeria: Evidence from Business Enterprise Survey

In this paper, we provide new evidence on the determinants of business enterprise performance by combining the structure conduct performance, efficiency structure and business environment factors. In particular, we focus on the major determining factors of MSMEs performance in Nigeria. We further account for possible regional variation in MSMEs performance using a cross sectional Ordinary Least Squares (OLS) with fixed effects. The latest 2014 World Bank Enterprise Survey (WBES) data for Nigeria was used and the results obtained shows that skilled labor, capital intensity, age, size, foreign ownership, percentage of export, research & development as well as bribe payment have a positive impact on MSMEs performance. Although, bribe payment is positive, it is not significant to MSME performance. This is because bribery does not translate to outright performance, rather it is a form of illegal extortion from MSMEs by government officials in order to allow them remain in business. On the other hand, the study found degree of competition, poor electricity supply, high insecurity and difficulty in accessing finance as major setbacks to MSMEs performance in Nigeria. While we found skilled labor, age of enterprise and size to contribute significantly to MSMEs performance, contrary to some findings in the literature, we found capital intensity, foreign ownership, firm’s export, bribe payment, research & development, degree of competition, outage intensity, insecurity and difficulty in obtaining finance to be insignificant to MSMEs performance in Nigeria

The Determinants of Micro, Small and Medium Enterprises’ (MSMEs) Performance in Nigeria: Evidence from Business Enterprise Survey

In this paper, we provide new evidence on the determinants of business enterprise performance by combining the structure conduct performance, efficiency structure and business environment factors. In particular, we focus on the major determining factors of MSMEs performance in Nigeria. We further account for possible regional variation in MSMEs performance using a cross sectional Ordinary Least Squares (OLS) with fixed effects. The latest 2014 World Bank Enterprise Survey (WBES) data for Nigeria was used and the results obtained shows that skilled labor, capital intensity, age, size, foreign ownership, percentage of export, research & development as well as bribe payment have a positive impact on MSMEs performance. Although, bribe payment is positive, it is not significant to MSME performance. This is because bribery does not translate to outright performance, rather it is a form of illegal extortion from MSMEs by government officials in order to allow them remain in business. On the other hand, the study found degree of competition, poor electricity supply, high insecurity and difficulty in accessing finance as major setbacks to MSMEs performance in Nigeria. While we found skilled labor, age of enterprise and size to contribute significantly to MSMEs performance, contrary to some findings in the literature, we found capital intensity, foreign ownership, firm’s export, bribe payment, research & development, degree of competition, outage intensity, insecurity and difficulty in obtaining finance to be insignificant to MSMEs performance in Nigeria