We present Hubble Space Telescope near-infrared transmission spectroscopy of the transiting hot-Jupiter HAT-P-1b. We observed one transit with Wide Field Camera 3 using the G141 low-resolution grism ...to cover the wavelength range 1.087-1.678 μm. These time series observations were taken with the newly available spatial-scan mode that increases the duty cycle by nearly a factor of 2, thus improving the resulting photometric precision of the data. We measure a planet-to-star radius ratio of R
p/R
* = 0.117 09 ± 0.000 38 in the white light curve with the centre of transit occurring at 245 6114.345 ± 0.000 133 (JD). We achieve S/N levels per exposure of 1840 (0.061 per cent) at a resolution of Δλ = 19.2 nm (R ∼ 70) in the 1.1173-1.6549 μm spectral region, providing the precision necessary to probe the transmission spectrum of the planet at close to the resolution limit of the instrument. We compute the transmission spectrum using both single target and differential photometry with similar results. The resultant transmission spectrum shows a significant absorption above the 5σ level matching the 1.4 μm water absorption band. In solar composition models, the water absorption is sensitive to the ∼1 m bar pressure levels at the terminator. The detected absorption agrees with that predicted by a 1000 K isothermal model, as well as with that predicted by a planetary-averaged temperature model.
ABSTRACT
The distance to the Galactic centre R0 is a fundamental parameter for understanding the Milky Way, because all observations of our Galaxy are made from our heliocentric reference point. The ...uncertainty in R0 limits our knowledge of many aspects of the Milky Way, including its total mass and the relative mass of its major components, and any orbital parameters of stars employed in chemo-dynamical analyses. While measurements of R0 have been improving over a century, measurements in the past few years from a variety of methods still find a wide range of R0 being somewhere within 8.0 to $8.5\, \mathrm{kpc}$. The most precise measurements to date have to assume that Sgr A* is at rest at the Galactic centre, which may not be the case. In this paper, we use maps of the kinematics of stars in the Galactic bar derived from APOGEE DR17 and Gaia EDR3 data augmented with spectrophotometric distances from the astroNN neural-network method. These maps clearly display the minimum in the rotational velocity vT and the quadrupolar signature in radial velocity vR expected for stars orbiting in a bar. From the minimum in vT, we measure $R_0 = 8.23\pm 0.12\, \mathrm{kpc}$. We validate our measurement using realistic N-body simulations of the Milky Way. We further measure the pattern speed of the bar to be $\Omega _\mathrm{bar} = 40.08\pm 1.78\, \mathrm{km\, s}^{-1}\,\mathrm{kpc}^{-1}$. Because the bar forms out of the disc, its centre is manifestly the barycentre of the bar+disc system and our measurement is therefore one of the most robust and accurate measurements of R0 to date.
Compelling evidence indicates that two autosomal recessive Parkinson's disease genes, PINK1 (PARK6) and Parkin (PARK2), cooperate to mediate the autophagic clearance of damaged mitochondria ...(mitophagy). Mutations in the F-box domain-containing protein Fbxo7 (encoded by PARK15) also cause early-onset autosomal recessive Parkinson's disease, by an unknown mechanism. Here we show that Fbxo7 participates in mitochondrial maintenance through direct interaction with PINK1 and Parkin and acts in Parkin-mediated mitophagy. Cells with reduced Fbxo7 expression showed deficiencies in translocation of Parkin to mitochondria, ubiquitination of mitofusin 1 and mitophagy. In Drosophila, ectopic overexpression of Fbxo7 rescued loss of Parkin, supporting a functional relationship between the two proteins. Parkinson's disease-causing mutations in Fbxo7 interfered with this process, emphasizing the importance of mitochondrial dysfunction in Parkinson's disease pathogenesis.
Abstract Polyethylene glycol (PEG) surface modification can make nanomaterials highly hydrophilic, reducing their sequestration in the reticuloendothelial system. In this study, polyamidoamine ...(PAMAM) dendrimers bearing gadolinium (Gd) chelates were PEGylated with different PEG-chain lengths, and the effects on paramagnetic and pharmacokinetic properties were evaluated. Specifically, Gd chelate-bearing PAMAM dendrimers (generations 4 and 5; G4 and G5) were conjugated with two different PEG chains (2 kDa and 5 kDa; 2k and 5k). Long PEG chains (5k) on the smaller (G4) dendrimer resulted in reduced relaxivity compared to non-PEGylated dendrimers, whereas short PEG chains (2k) on a larger (G5) dendrimer produced relaxivities comparable to non-PEGylated G4 dendrimers. The relaxivity of all PEGylated or lysine-conjugated dendrimers increased at higher temperature, whereas that of intact G4 Gd-PAMAM dendrimer decreased. All PEGylated dendrimers had minimal liver and kidney uptake and remained in circulation for at least 1 hour. Thus, surface-PEGylated Gd-PAMAM dendrimers showed decreased plasma clearance and prolonged retention in the blood pool. Shorter PEG, higher generation conjugates led to higher relaxivity. From the Clinical Editor In this study, polyamidoamine dendrimers bearing gadolinium (Gd) chelates were PEGylated with different PEG-chain lengths, and the effects on paramagnetic and pharmacokinetic properties were evaluated.
Phencyclidine (PCP), a non-competitive antagonist of ionotropic
N-methyl-
D-aspartate (NMDA) receptors, produces psychotomimetic effects, such as a disruption in prepulse inhibition (PPI) of the ...startle response. NMDA antagonists also induce locomotor hyperactivity in rodents. We hypothesized that, like NMDA receptors, metabotropic glutamate receptors (mGluRs) modulate PPI and locomotor activity either alone or, in the case of mGluR5, via interaction with NMDA receptors. Rats treated with the mGluR5 antagonist MPEP (2-methyl-6-phenylethynylpyridine) or the mGluR2/3 agonist LY314582, either alone or in combination with PCP, were tested in PPI and locomotor activity paradigms. Neither MPEP nor LY314582 altered PPI. MPEP, but not LY314582, potentiated the PPI-disruptive effects of PCP. MPEP alone did not alter locomotor or exploratory behavior, but augmented the complex, time-dependent locomotor-stimulating effects of PCP. LY314582 dose-dependently decreased locomotor activity and exploratory holepokes. LY314582 did not alter the PCP-induced increases in locomotor activity, but further decreased the number of holepokes. The effects of MPEP on the response to PCP may reflect the cooperation and co-localization of NMDA and mGlu5 receptors.
Summary
In the present study, we used national health care databases to estimate fracture incidence rates (IRs) and compared these IRs based on imputed data. We showed that imputation could lead to ...both over- and underestimation of IRs, and future research should therefore focus on how to improve those imputations.
Introduction
Osteoporosis is a major public health burden through associated (osteoporotic) fractures. In Denmark, the incidence rates (IRs) of hip fracture are widely available. However, there is limited data about other fracture sites. A recent report could only provide imputed IRs, although nationwide data is readily available in electronic healthcare databases. Therefore, our aim was to estimate fracture site-specific IRs for Denmark in 2011 and to compare those to the previously reported imputed data.
Methods
Data from the Danish National Hospital Discharge Register was used to estimate age- and gender-specific IRs for any fracture as well as for different fracture sites in the Danish population aged 20 years and older in 2011. Hip fracture IRs were stratified to sub-sites, and IRs were determined for all hip fractures which were confirmed by surgery.
Results
The total number of incident fractures in 2011 was 80,760 (IR 191, 95 % confidence interval (CI) 190–192 (per 10,000 person-years)), of which 35,398 (43.8 %, IR 171, 95 % CI 169–173) occurred in men and 45,362 (56.2 %, IR 211, 95 % CI 209–213) in women. The majority of the fractures occurred in the population aged 50 years and older (
n
= 50,470, IR 249, 95 % CI 247–251). The numbers of any hip fracture were lower than the previously imputed estimates, whereas the number of forearm fractures was higher.
Conclusion
We showed age- and gender-specific fracture rates for any fracture as well as for different fracture sites. The IRs of most fracture sites increased with age. Estimating the number of fractures for Denmark based on imputation of data from other countries led to both over- and underestimation. Future research should therefore focus on how to improve those imputations as not all countries have nationwide registry data.
We present Hubble Space Telescope (HST) optical transmission spectra of the transiting hot-Jupiter WASP-12b, taken with the Space Telescope Imaging Spectrograph instrument. The resulting spectra ...cover the range 2900-10 300 A which we combined with archival Wide Field Camera 3 spectra and Spitzer photometry to cover the full optical to infrared wavelength regions. With high spatial resolution, we are able to resolve WASP-12A's stellar companion in both our images and spectra, revealing that the companion is in fact a close binary M0V pair, with the three stars forming a triple-star configuration. We derive refined physical parameters of the WASP-12 system, including the orbital ephemeris, finding the exoplanet's density is ~20 per cent lower than previously estimated. From the transmission spectra, we are able to decisively rule out prominent absorption by TiO in the exoplanet's atmosphere, as there are no signs of the molecule's characteristic broad features nor individual bandheads. Strong pressure-broadened Na and K absorption signatures are also excluded, as are significant metal-hydride features. We compare our combined broad-band spectrum to a wide variety of existing aerosol-free atmospheric models, though none are satisfactory fits. However, we do find that the full transmission spectrum can be described by models which include significant opacity from aerosols: including Rayleigh scattering, Mie scattering, tholin haze and settling dust profiles. The transmission spectrum follows an effective extinction cross-section with a power law of index α, with the slope of the transmission spectrum constraining the quantity αT = -3528 ± 660 K, where T is the atmospheric temperature. Rayleigh scattering (α = -4) is among the best-fitting models, though requires low terminator temperatures near 900 K. Sub-micron size aerosol particles can provide equally good fits to the entire transmission spectrum for a wide range of temperatures, and we explore corundum as a plausible dust aerosol. The presence of atmospheric aerosols also helps to explain the modestly bright albedo implied by Spitzer observations, as well as the near blackbody nature of the emission spectrum. Ti-bearing condensates on the cooler night-side is the most natural explanation for the overall lack of TiO signatures in WASP-12b, indicating the day/night cold trap is an important effect for very hot Jupiters. These findings indicate that aerosols can play a significant atmospheric role for the entire wide range of hot-Jupiter atmospheres, potentially affecting their overall spectrum and energy balance. PUBLICATION ABSTRACT
We present Hubble Space Telescope optical and near-IR transmission spectra of the transiting hot-Jupiter WASP-31b. The spectrum covers 0.3-1.7 mu m at a resolution R similar to 70, which we combine ...with Spitzer photometry to cover the full-optical to IR. The spectrum is dominated by a cloud deck with a flat transmission spectrum which is apparent at wavelengths > 0.52 mu m. The cloud deck is present at high altitudes and low pressures, as it covers the majority of the expected optical Na line and near-IR H2O features. While Na I absorption is not clearly identified, the resulting spectrum does show a very strong potassium feature detected at the 4.2- sigma confidence level. Broadened alkali wings are not detected, indicating pressures below similar to 10 mbar. The lack of Na and strong K is the first indication of a sub-solar Na/K abundance ratio in a planetary atmosphere (lnNa/K = -3.3 plus or minus 2.8), which could potentially be explained by Na condensation on the planet's night side, or primordial abundance variations. A strong Rayleigh scattering signature is detected at short wavelengths, with a 4- sigma significant slope. Two distinct aerosol size populations can explain the spectra, with a smaller sub-micron size grain population reaching high altitudes producing a blue Rayleigh scattering signature on top of a larger, lower lying population responsible for the flat cloud deck at longer wavelengths. We estimate that the atmospheric circulation is sufficiently strong to mix micron size particles upwards to the required 1-10 mbar pressures, necessary to explain the cloud deck. These results further confirm the importance of clouds in hot Jupiters, which can potentially dominate the overall spectra and may alter the abundances of key gaseous species.
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