The effect of pre-plasma on core heating in cone-guiding fast ignition is evaluated by two-dimensional particle-in-cell (PIC) and Fokker–Planck (FP) simulations. If the long-scale pre-plasma exists ...in the cone, the generated fast electron energy becomes too high for effective core heating. As a result, the energy coupling from laser to core η
L→core
is reduced by 80% compared with the case without a pre-plasma. Even for the case without a pre-plasma, η
L→core
obtained in the simulation is smaller than that required for 5 keV heating in FIREX-I. In order to enhance η
L→core
, we propose a new target design ‘extended double cone with short inner cone wall’ for fast electron guiding to imploded core and show sufficient improvement of heating efficiency using this new cone on the basis of PIC and FP hydro-simulations.
Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a space‐borne instrument dedicated to monitoring high‐energy transients, including Terrestrial Gamma‐ray Flashes ...(TGFs) and Terrestrial Electron Beams (TEBs). We implemented a TGF/TEB search algorithm for GECAM, with which 147 bright TGFs, 2 typical TEBs and 2 special TEB‐like events are identified during an effective observation time of ∼9 months. We show that, with gamma‐ray and charged particle detectors, GECAM can effectively identify and distinguish TGFs and TEBs, and measure their temporal and spectral properties in detail. A very high TGF‐lightning association rate of ∼80% is obtained between GECAM and GLD360 in east Asia region.
Plain Language Summary
Terrestrial gamma‐ray flashes (TGFs) and Terrestrial Electron Beams (TEBs) represent the most energetic radioactive phenomena in the atmosphere of the Earth. They reflect a natural particle accelerator that can boost electrons up to at least several tens of mega electron volts and produce gamma‐ray radiation. With novel detection technologies, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a new powerful instrument to observe TGFs and TEBs, as well as study their properties. For example, it is difficult for most space‐borne high‐energy instruments to distinguish between TGFs and TEBs. However, we show here that, with the joint observation of gamma‐ray and charged particle detectors, GECAM can effectively identify TGFs and TEBs. GECAM can also reveal their fine features in the light curves and spectra.
Key Points
During 9‐month observation, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) has detected 147 bright Terrestrial Gamma‐ray Flashes (TGFs), 2 typical Terrestrial Electron Beams (TEBs), and 2 special TEB‐like events
With novel detector design, GECAM can effectively classify TGFs and TEBs, and reveal their fine temporal features
We obtained a very high TGF‐lightning association rate (∼80%) between GECAM and GLD360 in east Asia region
OBJECTIVETo evaluate the effect of photobiomodulation (PBM) on the drainage of brain interstitial fluid (ISF) and to investigate the possible mechanism of the positive effect of PBM on Alzheimer's ...disease (AD). METHODSTwenty-four SD male rats were randomly divided into PBM group (n=12), sham PBM group (n=6), and negative control group (n=6). According to the injection site of tracer, the PBM group was further divided into PBM-ipsilateral traced group (n=6) and PBM-contralateral traced group (n=6). Rats in the PBM group and the sham PBM group were exposed to the dura minimally invasively on the skull corresponding to the frontal cortical area reached by ISF drainage from caudate nucleus region. The PBM group was irradiated by using 630 nm red light (5-6 mW/cm2), following an irradiation of 5 min with a 2 min pause, and a total of 5 times; the sham PBM group was kept in the same position for the same time using the light without power. The negative control group was kept without any measure. After PBM, tracer w
Highlights • Diverse macrophage populations reside beneath the basilar membrane of the cochlea. • Monocytes undergo a time-dependent transformation into macrophages after acoustic overstimulation. • ...Acoustic overstimulation induces the upregulation of antigen-presenting proteins in the mononuclear phagocytes. • CD4+ T cells participate in antigen-presenting activity in response to acoustic overstimulation. • Activation of antigen-presenting function is an immune cell response to acoustic overstimulation.
Abstract
Variability is one of the main observational characteristics of blazars. Studying variability is an efficient method to reveal the nature of active galactic nuclei. In the present work, we ...report optical
R
-band photometry observations of a TeV blazar, 1ES 2344 + 514, carried out with a 70 cm telescope in the period of 1998 July–2017 November at Abastumani Observatory, Georgia. Based on the optical
R
-band observations, the optical variation behaviors on both short timescales and long timescales are investigated. Three methods (Jurkevich, discrete correlation function, and power spectrum analysis) are used to investigate periodicity in the light curve. In addition, combined with multiwavelength data, the jet physical properties are discussed. The following conclusions are drawn: (1) A variability of Δ
R
= 0.155 mag (15.356 − 15.201 mag) over a timescale of Δ
T
= 12.99 minutes is detected during our 628 days of monitoring. (2) According to the Kelvin–Helmholtz thermal instability, if the magnetic field intensity (
B
) for the source is greater than a critical value (
B
c
), it will reduce the incidence of intraday variations in the light curves. (3) The physical parameters of the dissipation region are obtained by fitting the spectral energy distribution with a one-zone synchrotron self-Compton model for the average and flare states. (4) The three methods show that there are periods of
P
= 2.72 ± 0.47 yr,
P
= 1.61 ± 0.18 yr,
P
= 1.31 ± 0.17 yr, and
P
= 1.05 ± 0.07 yr. When a binary black hole system is adopted with a period of
P
= 2.72 ± 0.41 yr, we obtain the orbital parameters for the binary black hole system as follows:
M
= 8.08 × 10
9
M
⊙
, the sum of the semiaxes is
r
= 7.18 × 10
16
cm, and the lifetime of the binary black hole is
τ
merge
= 6.24 × 10
2
yr.
Abstract
Both short (≤6 h per night) and long sleep duration (≥9 h per night) are associated with increased risk of chronic diseases. Despite evidence linking habitual sleep duration and risk of ...disease, the genetic determinants of sleep duration in the general population are poorly understood, especially outside of European (EUR) populations. Here, we report that a polygenic score of 78 European ancestry sleep duration single-nucleotide polymorphisms (SNPs) is associated with sleep duration in an African (n = 7288; P = 0.003), an East Asian (n = 13 618; P = 6 × 10−4) and a South Asian (n = 7485; P = 0.025) genetic ancestry cohort, but not in a Hispanic/Latino cohort (n = 8726; P = 0.71). Furthermore, in a pan-ancestry (N = 483 235) meta-analysis of genome-wide association studies (GWAS) for habitual sleep duration, 73 loci are associated with genome-wide statistical significance. Follow-up of five loci (near HACD2, COG5, PRR12, SH3RF1 and KCNQ5) identified expression-quantitative trait loci for PRR12 and COG5 in brain tissues and pleiotropic associations with cardiovascular and neuropsychiatric traits. Overall, our results suggest that the genetic basis of sleep duration is at least partially shared across diverse ancestry groups.
Polygenic risk scores (PRS) have the potential to identify individuals at risk of diseases, optimizing treatment, and predicting survival outcomes. Here, we construct and validate a genome-wide ...association study (GWAS) derived PRS for nasopharyngeal carcinoma (NPC), using a multi-center study of six populations (6 059 NPC cases and 7 582 controls), and evaluate its utility in a nested case-control study. We show that the PRS enables effective identification of NPC high-risk individuals (AUC = 0.65) and improves the risk prediction with the PRS incremental deciles in each population (P
ranging from 2.79 × 10
to 4.79 × 10
). By incorporating the PRS into EBV-serology-based NPC screening, the test's positive predictive value (PPV) is increased from an average of 4.84% to 8.38% and 11.91% in the top 10% and 5% PRS, respectively. In summary, the GWAS-derived PRS, together with the EBV test, significantly improves NPC risk stratification and informs personalized screening.
We conducted two three-dimensional numerical models to investigate the effects of the surrounding surface surcharge on the deformation of the retaining structure. The results obtained by the finite ...element model are in good agreement with the field measurements. The deflection of the diaphragm wall increased by 2-3 times owing to the surrounding surface surcharge, which implies that the surrounding surface surcharge magnifies the excavation-space effect. The maximum wall deflections were approximately 0.03-0.05 H (H is the excavation depth) in the case without surface surcharge. However, the maximum wall deflections increased up to 0.05-0.19 H when surrounding surface surcharges were applied on the surface ground around excavation. The surrounding surface surcharge leads to the increase of the maximum wall deflection.
•Mo absorption and Mo substituted at S site induce the magnetism.•The origin of the magnetism is mainly from the Mo adatom and substitutional atom.•SMo and VMo realize the n-type and p-type ...semiconductor behavior, respectively.
The structural, electronic and magnetic properties of intrinsic defects in monolayer MoS2 have investigated systematically by first-principles calculations based on density functional theory. The results show that S vacancy and S adsorption is the most favorable intrinsic defect under Mo-rich and S-rich conditions, respectively. Mo atom adsorbed on monolayer MoS2 and Mo atom substituted at S site induced the spin-polarization, which gives rise to total magnetic moment of 4.0μB and 2.0μB, respectively. The magnetism is mainly origin from the Mo adatom and the Mo substitutional atom, respectively. For the Mo and S adsorption, the Mo atom and S atom prefer to adsorb on top of the Mo atom and the S atom, respectively. In addition, SMo and VMo can realize the n-type and p-type semiconductor behavior, respectively. These predictions are useful for the spintronic devices designs.
Ti–22Fe–23Mn(at.%) eutectic brazing alloy ribbon fabricated by vacuum arc remelting and rapid solidification as filler metal used to vacuum braze Ti–45Al–2Mn–2Nb–1B(at.%) alloy. The effects of ...brazing temperature and time on the interfacial microstructure and joining properties were investigated in detail. The microstructure of the Ti–20Fe–21Mn brazing alloy presented excellent diffusion ability, and the brazed joints mainly consisted of α2/γ lamellar phase, single α2 phase, B2 phase, and boride. The brazed joint's tensile strength first increased and then decreased with the brazing temperature in the range of 1170 °C–1250 °C, and the holding time varied from 5 min to 60 min. The highest tensile strength at room temperature was 540 MPa when the joint brazed at 1230 °C for 45 min. The high-temperature tensile strength first increased and then decreased with the testing temperature. The high-temperature tensile strength of Ti–22Fe–23Mn(at.%) alloy was superior to Ti–Zr–Cu–Ni (at.%) alloy. The high-temperature tensile strength was lower than 45XD alloy below 850 °C. However, the tensile strength was closer to 45XD alloy when the testing temperature varied from 900 °C to 1000 °C. All the cracks nucleated and propagated in the poor boride zone, and the fracture surfaces presented typical brittle cleavage fracture characteristics.
•The Ti–Fe–Mn brazing alloy was fabricated to braze 45XD alloy.•The relationship between the brazing parameter and the microstructure of the joint was investigated.•The tensile strength was superior to other brazing alloy.•The 900 °C, 950 °C and 1000 °C tensile strength of the brazed joint reached 45XD alloy strength.
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