Repeated Plyometric Exercise Attenuates Blood Glucose in Healthy Adults

International Journal of Exercise Science 10(7): 1076-1084, 2017. Plyometric exercise is popular in commercial exercise programs aiming to maximize energy expenditure for weight loss. However, the effect of plyometric exercise on blood glucose is unknown. The purpose of this study was to investigate the effect of relatively high intensity plyometric exercise on blood glucose. Thirteen subjects (6 females age= 21.8 ± 1.0 yrs.; height= 163.7 ± 7.8 cm; mass= 60.8 ± 6.7 kg and 7 males age= 22.0 ± 2.6 yrs.; height= 182.3 ± 3.6 cm; mass= 87.4 ± 12.5 kg) volunteered to participate. Subjects completed two random conditions on two separate days, consisting of either five sets of 10 maximal effort countermovement squat jumps (SJ) with 50 seconds’ rest between sets or quiet sitting (SIT) for the time equated to the SJ duration (~4min). Immediately after each condition, subjects drank 75g of anhydrous glucose (CHO) in 100ml of water. Blood glucose measurements were taken via finger prick pre and immediately post SJ or SIT, and 5, 15, 30, and 60 min post. A 2x6 (condition x time) ANOVA revealed a significant interaction where SJ blood glucose was lower at 15 (114.0 ± 14.6 mg/dl) and 30 (142.1 ± 22.5 mg/dl) min compared to SIT (15min 130.8 ± 14.0 mg/dl and 30min 159.3 ± 21.0 mg/dl). The current plyometric protocol attenuated CHO-induced blood glucose at 15 and 30 min. This may be due to increased physiological stress applied to the muscles, thus increasing muscular glucose uptake

A New 24 micron Phase Curve for upsilon Andromedae b

We report the detection of 24 micron variations from the planet-hosting upsilon Andromedae system consistent with the orbital periodicity of the system's innermost planet, upsilon And b. We find a peak-to-valley phase curve amplitude of 0.00130 times the mean system flux. Using a simple model with two hemispheres of constant surface brightness and assuming a planetary radius of 1.3 Jupiter radii gives a planetary temperature contrast of >900 K and an orbital inclination of >28 degrees. We further report the largest phase offset yet observed for an extrasolar planet: the flux maximum occurs ~80 degrees before phase 0.5. Such a large phase offset is difficult to reconcile with most current atmospheric circulation models. We improve on earlier observations of this system in several important ways: (1) observations of a flux calibrator star demonstrate the MIPS detector is stable to 10^-4 on long timescales, (2) we note that the background light varies systematically due to spacecraft operations, precluding use of this background as a flux calibrator (stellar flux measured above the background is not similarly affected), and (3) we calibrate for flux variability correlated with motion of the star on the MIPS detector. A reanalysis of our earlier observations of this system is consistent with our new result.Comment: Submitted to ApJ. 15 pages, 6 figures, 4 table

Mass loss from the exoplanet WASP-12b inferred from Spitzer phase curves

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.The exoplanet WASP-12b is the prototype for the emerging class of ultrahot, Jupiter-mass exoplanets. Past models have predicted – and near-ultraviolet observations have shown – that this planet is losing mass. We present an analysis of two sets of 3.6 and 4.5 μmSpitzer phase curve observations of the system which show clear evidence of infrared radiation from gas stripped from the planet, and the gas appears to be flowing directly toward or away from the host star. This accretion signature is only seen at 4.5 μm⁠, not at 3.6 μm⁠, which is indicative either of CO emission at the longer wavelength or blackbody emission from cool, ≲600 K gas. It is unclear why WASP-12b is the only ultrahot Jupiter to exhibit this mass-loss signature, but perhaps WASP-12b’s orbit is decaying as some have claimed, while the orbits of other exoplanets may be more stable; alternatively, the high-energy irradiation from WASP-12A may be stronger than the other host stars. We also find evidence for phase offset variability at the level of 6.4σ (46.2°) at 3.6 μm⁠

Selection into youth cricket academies: The influence of relative age and maturity status

The aim of the study was to examine the birth quartile and maturity status distributions of male academy cricketers. Participants included 213 junior cricket players, aged between 9 and 18 years. Players were separated into birth quartiles and also grouped as early, average or late maturers. For the whole cohort, there was a medium effect bias towards players born in BQ1, but the number of early, average and late maturers was as expected. However, there were significantly more early maturers in the U10 and U11 groups than expected, and maturity distributions of the BQ groups showed that there was a small effect size bias towards early maturers in BQ4. Selection biases towards cricketers who are born earlier in the competitive year are consistent from U9 to U16, but more prevalent in the U12 and U14 age groups. There is a bias towards early maturers at U10 and U11, but this reduces as age increases. Practitioners working in academy pathways should be encouraged to assess the maturity status of players to assist in the retention and progression of players. Relative age effects should also be considered, and strategies may be required to identify players born later in the year

Limits on the ultra-bright Fast Radio Burst population from the CHIME Pathfinder

We present results from a new incoherent-beam Fast Radio Burst (FRB) search on the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Pathfinder. Its large instantaneous field of view (FoV) and relative thermal insensitivity allow us to probe the ultra-bright tail of the FRB distribution, and to test a recent claim that this distribution's slope, $\alpha\equiv-\frac{\partial \log N}{\partial \log S}$, is quite small. A 256-input incoherent beamformer was deployed on the CHIME Pathfinder for this purpose. If the FRB distribution were described by a single power-law with $\alpha=0.7$, we would expect an FRB detection every few days, making this the fastest survey on sky at present. We collected 1268 hours of data, amounting to one of the largest exposures of any FRB survey, with over 2.4\,$\times$\,10$^5$\,deg$^2$\,hrs. Having seen no bursts, we have constrained the rate of extremely bright events to $<\!13$\,sky$^{-1}$\,day$^{-1}$ above $\sim$\,220$\sqrt{(\tau/\rm ms)}$ Jy\,ms for $\tau$ between 1.3 and 100\,ms, at 400--800\,MHz. The non-detection also allows us to rule out $\alpha\lesssim0.9$ with 95$\%$ confidence, after marginalizing over uncertainties in the GBT rate at 700--900\,MHz, though we show that for a cosmological population and a large dynamic range in flux density, $\alpha$ is brightness-dependent. Since FRBs now extend to large enough distances that non-Euclidean effects are significant, there is still expected to be a dearth of faint events and relative excess of bright events. Nevertheless we have constrained the allowed number of ultra-intense FRBs. While this does not have significant implications for deeper, large-FoV surveys like full CHIME and APERTIF, it does have important consequences for other wide-field, small dish experiments

Rotation of planet-harbouring stars

The rotation rate of a star has important implications for the detectability, characterisation and stability of any planets that may be orbiting it. This chapter gives a brief overview of stellar rotation before describing the methods used to measure the rotation periods of planet host stars, the factors affecting the evolution of a star's rotation rate, stellar age estimates based on rotation, and an overview of the observed trends in the rotation properties of stars with planets.Comment: 16 pages, 4 figures: Invited review to appear in 'Handbook of Exoplanets', Springer Reference Works, edited by Hans J. Deeg and Juan Antonio Belmont

Mass Loss from the Exoplanet WASP-12b Inferred from Spitzer Phase Curves

The exoplanet WASP-12b is the prototype for the emerging class of ultrahot, Jupiter-mass exoplanets. Past models have predicted – and near-ultraviolet observations have shown – that this planet is losing mass. We present an analysis of two sets of 3.6 and 4.5 μm Spitzer phase curve observations of the system which show clear evidence of infrared radiation from gas stripped from the planet, and the gas appears to be flowing directly toward or away from the host star. This accretion signature is only seen at 4.5 μm⁠, not at 3.6 μm⁠, which is indicative either of CO emission at the longer wavelength or blackbody emission from cool, ≲600 K gas. It is unclear why WASP-12b is the only ultrahot Jupiter to exhibit this mass-loss signature, but perhaps WASP-12b’s orbit is decaying as some have claimed, while the orbits of other exoplanets may be more stable; alternatively, the high-energy irradiation from WASP-12A may be stronger than the other host stars. We also find evidence for phase offset variability at the level of 6.4σ (46.2°) at 3.6 μm⁠

Infrared Transmission Spectroscopy of the Exoplanets HD209458b and XO-1b Using the Wide Field Camera-3 on the Hubble Space Telescope

Exoplanetary transmission spectroscopy in the near-infrared using the Hubble Space Telescope (HST) NICMOS is currently ambiguous because different observational groups claim different results from the same data, depending on their analysis methodologies. Spatial scanning with HST/WFC3 provides an opportunity to resolve this ambiguity. We here report WFC3 spectroscopy of the giant planets HD 209458b and XO-1b in transit, using spatial scanning mode for maximum photon-collecting efficiency. We introduce an analysis technique that derives the exoplanetary transmission spectrum without the necessity of explicitly decorrelating instrumental effects, and achieves nearly photon-limited precision even at the high flux levels collected in spatial scan mode. Our errors are within 6% (XO-1) and 26% (HD 209458b) of the photon-limit at a resolving power of λ/δλ ~ 70, and are better than 0.01% per spectral channel. Both planets exhibit water absorption of approximately 200 ppm at the water peak near 1.38 μm. Our result for XO-1b contradicts the much larger absorption derived from NICMOS spectroscopy. The weak water absorption we measure for HD 209458b is reminiscent of the weakness of sodium absorption in the first transmission spectroscopy of an exoplanet atmosphere by Charbonneau et al. Model atmospheres having uniformly distributed extra opacity of 0.012 cm2 g−1 account approximately for both our water measurement and the sodium absorption. Our results for HD 209458b support the picture advocated by Pont et al. in which weak molecular absorptions are superposed on a transmission spectrum that is dominated by continuous opacity due to haze and/or dust. However, the extra opacity needed for HD 209458b is grayer than for HD 189733b, with a weaker Rayleigh component

Disseminated and Congenital Toxoplasmosis in a Mother and Child With Activated PI3-Kinase δ Syndrome Type 2 (APDS2): Case Report and a Literature Review of Toxoplasma Infections in Primary Immunodeficiencies

Phosphoinositide 3-kinase (PI3K) plays an integral role in lymphocyte function. Mutations in PIK3CD and PIK3R1, encoding the PI3K p110δ and p85α subunits, respectively, cause increased PI3K activity and result in immunodeficiency with immune dysregulation. We describe here the first cases of disseminated and congenital toxoplasmosis in a mother and child who share a pathogenic mutation in PIK3R1 and review the mechanisms underlying susceptibility to severe Toxoplasma gondii infection in activated PI3Kδ syndrome (APDS) and in other forms of primary immunodeficiency