The High-Granularity Timing Detector is a detector proposed for the ATLAS Phase II upgrade. The detector, based on the Low-Gain Avalanche Detector (LGAD) technology, will cover the pseudo-rapidity ...region of 2.4<|η|<4.0 with two end caps on each side and a total area of 6.4 m2. The timing performance can be improved by implanting an internal gain layer that can produce signals with a fast rising edge. It significantly improves the signal-to-noise ratio. The required average timing resolution per track for a minimum ionizing particle is 30 ps at the start and 50 ps at the end of the HL-LHC operation. This is achieved with several layers of LGAD. The innermost region of the detector would accumulate a 1MeV neutron-equivalent fluence up to 2.5× 1015 neq/cm2 including a safety factor of 1.5 before being replaced during the scheduled shutdowns. The addition of this new detector is expected to play an important role in the mitigation of high pile-ups at the HL-LHC. The layout and performance of the various versions of LGAD prototypes produced by Hamamatsu (HPK) have been studied by the ATLAS Collaboration. The breakdown voltages, depletion voltages, inter-pad gaps, collected charge as well as the time resolution have been measured and the production yield of large size sensors has been evaluated.
We present the first direct measurements of the terahertz atmospheric transmission above Dome A, the highest point on the Antarctic plateau at an elevation of 4.1 km. The best-quartile atmospheric ...transmission during the Austral winter is 80% at a frequency of 661 GHz (453 μm), corresponding to a precipitable water vapor column of 0.1 mm. Daily averages as low as 0.025 mm were observed. The Antarctic atmosphere is very stable, and excellent observing conditions generally persist for many days at a time. The exceptional conditions over the high Antarctic plateau open new far-infrared spectral windows to ground-based observation. These windows contain important spectral-line diagnostics of star formation and the interstellar medium which would otherwise only be accessible to airborne or space telescopes.
Engineered nanoparticles (ENPs) are advanced, high-throughput materials that have revolutionized almost every aspect of human life over the past decade with its numerous commercial applications ...across the globe. However, these particles have made their way into the environment through various pathways, eliciting unintended environmental consequences, and endangered various ecosystems and human health. Microalgae and their related microbial communities act as one of the key indicators of nano-toxicity, and play essential roles in bioremediation and bioenergy productions. In this review, we analyzed the interactions of nanoparticles with microalgae and the associated microbial communities along with its influence on the remediation capacities of pollutants such as organic pollutants, nitrogen and phosphorus. We also provide a comprehensive insight into the transcriptomics, proteomics and metagenomics of ENPs influenced microalgae and their related microbial communities to identify the in-depth protective and metabolic mechanisms. The information provided herein can extend the understanding of the effect of nanoparticles on environmental processes and might be useful in designing its disposal and treatment strategies.
Summary
Men with hyperlipidemia are more likely to have erectile dysfunction (ED) than those without hyperlipidemia, but the mechanisms are not fully understood. The aim of this study was to ...investigate the underlying mechanism of ED caused by hyperlipidemia. Fourteen 8‐week‐old Sprague–Dawley rats were randomly divided into two groups: a control group and a hyperlipidemia group (fed chow containing 4% cholesterol and 1% cholic acid). After 6 months, we assessed erectile function by performing cavernous nerve electrostimulation followed by intracavernosal pressure/mean arterial pressure measurements, as well as plasma lipid profile assessment in all rats. A transferase‐mediated nick end labeling (TUNEL) assay, immunohistochemical staining and Western blotting were performed to determine the levels of apoptosis, autophagy and fibrosis in the penile tissue. Compared with the control group, the hyperlipidemia group exhibited: (i) increased plasma lipid levels; (ii) decreased erectile function; (iii) a decreased smooth muscle/collagen ratio; (iv) increased fibrosis; (v) increased apoptosis and decreased autophagy. Overall, hyperlipidemia may attenuate erectile function in rats by causing of cavernosal fibrosis.
Interstitially doped Cu3N represents a model system to study “enclosed atoms” in a cuboctahedral environment. Based on density functional theory calculations using the generalized gradient ...approximation, we report a systematic study of 3d-transition metals (TM), as well as Li-, H-, and Pd-doped Cu3N, whose stabilities and magnetic properties are investigated. The interposition of 3d-TM atoms leads to mechanically stable yet brittle structures, with Sc, Mn, Ni, Cu, Zn possessing relatively small positive (endothermic) formation energies (0.12∼0.54eV/TM), suggesting it may be easier to realize them experimentally than other 3d-TM elements. Li-, H-, Pd-doping in Cu3N are exothermic, while Ti, V, Cr, Fe, and Co have higher formation energy (0.93∼1.39eV/TM) at a doping concentration 3.7 %. The fully 3d-TM doped Cu3N systems exhibit a wide spectrum of magnetic properties, ranging from weak antiferromagnetic (Sc-), antiferromagnetic (Ti-, V-, Cr-) to ferromagnetic (Mn-, Fe-, Co-) and non-magnetic (Ni-, Cu-, Zn-) behaviour. In particular, Ti:Cu3N exhibits weak itinerant magnetic properties with a large positive magnetovolume effect. All the 3d-TM atom intercalations into cubic Cu3N lead to a semiconductor-to-metal transition for both 100% and 3.7% doping, with the exception of Ni:Cu3N exhibiting a weak metallic or narrow semiconducting behaviour depending on the doping concentration.
We grew CdTexSe1−x (CTS) crystals from a Te-rich solution by using the traveling heater method (THM). The average size distribution and concentration of Te inclusions/precipitates in these as-grown ...samples were measured to be ~7×104cm−3, which is much lower than values typical for the present state-of-the-art commercial CdZnTe (CZT) material. Their low-temperature photoluminescence measurement indicates high quality of the material; however the resistivity obtained via I–V curve measurements was ~5×108Ω-cm, which is low in comparison to that required for gamma detectors. A well-resolved alpha response peak can be detected for both planar- and hemispherical detector geometry. The (μτ)e value for our as-grown sample at room temperature was found to be ~4×10−3cm2/V.
•CdTeSe grown by the traveling heater method.•Concentrations of the secondary phase found to be ~7×104cm−3, which is 5–8 times lower than standard commercial CZT.•The (μτ)e value for our as-grown sample at room temperature was found to be ~4×10−3cm2/V.
Abstract
We report the energy-resolved broadband timing analysis of the black hole X-ray transient MAXI J1631-479 during its 2019 outburst from February 11 to April 9, using data from the ...Insight−Hard X-ray Modulation Telescope (Insight-HXMT), which caught the source from its hard-intermediate state to the soft state. Thanks to the large effective area of Insight-HXMT at high energies, we are able to present the energy dependence of fast variability up to ∼100 keV. Type-C quasi-periodic oscillations (QPOs) with a frequency varying between 4.9 and 6.5 Hz are observed in the 1–100 keV energy band. While the QPO fractional rms increases with photon energy from 1 keV to ∼10 keV and remains more or less constant from ∼10 keV to ∼100 keV, the rms of the flat-top noise first increases from 1 keV to ∼8 keV and then drops to less than 0.1% above ∼30 keV. We suggest that the disappearance of the broadband variability above 30 keV could be caused by the nonthermal acceleration in the Comptonizing plasma. At the same time, the QPOs could be produced by the precession of either a small-scale jet or a hot inner flow model.
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