Abstract
We present the analysis of the brightest flare that was recorded in the Insight-HMXT data set in a broad energy range (2–200 keV) from the microquasar GRS 1915+105 during an unusual ...low-luminosity state. This flare was detected by Insight-HXMT among a series of flares during 2019 June 2 UTC 16:37:06–20:11:36 with a 2–200 keV luminosity of 3.4–7.27 × 10
38
erg s
−1
. Basing on the broadband spectral analysis, we find that the flare spectrum shows different behaviors during bright and faint epochs. The spectrum of the flare can be fitted with a model dominated by a power-law component. Additional components show up in the bright epoch with a hard tail and in the faint epoch with an absorption line of ∼6.78 keV. The reflection component of the latter is consistent with an inner disk radius ∼five times larger than that of the former. These results on the giant flare during the “unusual” low-luminosity state of GRS 1915+105 may suggest that the source experiences a possible fast transition from a jet-dominated state to a wind-dominated state. We speculate that the evolving accretion disk and the large-scale magnetic field may play important roles in this peculiar huge flare.
Summary Objective To determine whether mandibular condylar cartilage degradation induced by experimentally abnormal occlusion could be ameliorated via systemic administration of strontium or NBD ...peptide. Methods Six-week-old female C57BL/6J mice were used. From the seventh day after mock operation or unilateral anterior crossbite (UAC) treatment, the control and UAC mice were further respectively pharmacologically treated for 2 weeks or 4 weeks of saline (CON + Saline and UAC + Saline groups), SrCl2 (CON + SrCl2 and UAC + SrCl2 groups) or NBD peptide (CON + NBD peptide and UAC + NBD peptide groups). Changes in condylar cartilage and subchondral bone were assessed 21 and 35 days after mock operation or UAC procedure by histology and micro-CT. Real-time PCR and/or immunohistochemistry (IHC) were performed to evaluate changes in expression levels of col2a1, aggrecan, ADAMTS-5, tnf-α, il-1β, nfkbia, nuclear factor-kappaB phospho-p65 in condylar cartilage, and rankl/rank/opg in both condylar cartilage and subchondral bone. Results Cartilage degradation with decreased col2a1 and aggrecan expression, and increased ADAMTS-5, tnf-α/il1-β, nfkbia and NF-κB phospho-p65 was observed in UAC + Saline groups. Subchondral bone loss with increased osteoclast numbers and decreased opg/rankl ratio was found in UAC + Saline groups compared to age-match CON + Saline groups. Cartilage degradation and subchondral bone loss were reversed by treatment of SrCl2 or NBD peptide while the same dosage in control mice induced few changes in condylar cartilage and subchondral bone. Conclusions The results demonstrate reverse effect of systemic administration of strontium or NBD peptide on UAC-induced condylar cartilage degradation and subchondral bone loss.
Novel mechanisms for electromagnetic wave emission in the terahertz frequency regime emerging at the nanometer scale have recently attracted intense attention for the purpose of searching ...next-generation broadband THz emitters. Here, we report broadband THz emission, utilizing the interface inverse Rashba-Edelstein effect. By engineering the symmetry of the Ag/Bi Rashba interface, we demonstrate a controllable THz radiation (∼0.1-5 THz) waveform emitted from metallic Fe/Ag/Bi heterostructures following photoexcitation. We further reveal that this type of THz radiation can be selectively superimposed on the emission discovered recently due to the inverse spin Hall effect, yielding a unique film thickness dependent emission pattern. Our results thus offer new opportunities for versatile broadband THz radiation using the interface quantum effects.
This experiment was conducted to assess the comparative effects of dietary antibiotics and oregano essential oil (OEO) addition on growth performance, antioxidant status and intestinal health of ...broilers. A total of 384 one-day-old broilers were randomly allocated to 4 treatments with 6 replicates of 16 broilers each. The 4 treatments were: an antibiotic-free control diet (control), control + 20 mg/kg colistin sulfate and 20 mg/kg virginiamycin (antibiotics), control + 200 mg/kg natural oregano essential oil (NOEO), and control + 200 mg/kg synthetic oregano essential oil (SOEO). The experiment lasted for 42 d. Results showed that birds fed with OEO had greater (P < 0.05) average daily gain (ADG) and lower (P < 0.05) feed conversion ratio (FCR) than those fed with control diet during d 1 to 21. Besides, birds fed with NOEO had the greatest (P < 0.05) ADG in the four groups during d 22 to 42. The serum oxidative stress parameters showed that OEO improved (P < 0.05) the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione reductase (GR) of birds on day 21 and the activity of total antioxidant capacity (T-AOC) of birds on d 42. Relative to control, NOEO increased (P < 0.05) the activity of T-AOC in jejunum and decreased (P < 0.05) the level of malondialdehyde (MDA) in serum and jejunum. Moreover, OEO supplementation increased (P < 0.05) the concentrations of sIgA in duodenum and jejunum, Lactobacillus and total anaerobes in cecum, as well as activities of trypsin, chymotrypsin, lipase and amylase in duodenum, but restrained (P < 0.05) the amount of Escherichia coli. The NOEO supplementation increased (P < 0.05) total anaerobes of broilers on d 42 and the villus height to crypt depth ratio (VH/CD) of ileum. These results suggest that OEO improved antioxidant status and intestinal health of broilers which contributed to the growth performance improvement of broilers. Dietary OEO supplementation can be a promising alternative to antibiotic growth promoters for improving poultry production.
Weyl semimetals host chiral fermions with distinct chiralities and spin textures. Optical excitations involving those chiral fermions can induce exotic carrier responses, and in turn lead to novel ...optical phenomena. Here, we discover strong coherent terahertz emission from Weyl semimetal TaAs, which is demonstrated as a unique broadband source of the chiral terahertz wave. The polarization control of the THz emission is achieved by tuning photoexcitation of ultrafast photocurrents via the photogalvanic effect. In the near-infrared regime, the photon-energy dependent nonthermal current due to the predominant circular photogalvanic effect can be attributed to the radical change of the band velocities when the chiral Weyl fermions are excited during selective optical transitions between the tilted anisotropic Weyl cones and the massive bulk bands. Our findings provide a design concept for creating chiral photon sources using quantum materials and open up new opportunities for developing ultrafast opto-electronics using Weyl physics.
The purposes of this study were to compare Young's modulus values determined by shear wave ultrasound elastography (SWUE) with stiffness index obtained using a hand-held MyotonPRO device on the ...resting stiffness of gastrocnemius muscle belly and Achilles tendon; and to examine the test-retest reliability of those stiffness measurement using hand-held MyotonPRO. Twenty healthy volunteers participated in the study. The measurement values of muscle and tendon was determined in dominant legs. Each marker point was assessed using MyotonPRO and SWUE, respectively. Intra-operator reliability of MyotonPRO was established in 10 of the subjects. The correlation coefficients between the values of muscle and tendon stiffness indices determined by MyotonPRO and SWUE were calculated. Significant correlations were found for muscle and tendon stiffness and Young's modulus ranged from 0.463 to 0.544 (all P < 0.05). The intra-operator reliability ranged from good to excellent (ICC
= 0.787~0.928). These results suggest that the resting stiffness of gastrocnemius muscle belly and Achilles tendon measured by MyotonPRO is related to the Young's modulus of those quantified by SWUE. The MyotonPRO shows good intra-operator repeatability. Therefore, the present study shows that MyotonPRO can be used to assess mechanical properties of gastrocnemius muscle belly and Achilles tendon with a resting condition.
Objectives
We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.
Methods
The telomere restriction fragment (TRF) length of leukocytes in ...the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.
Results
Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.
Conclusion
The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.
Semi-crystalline polymers are now extensively used in various applications such as aircrafts, civilian structures, oil and gas platforms and electronics. They are, however, inherently damage prone, ...and over time, the formation of damages such as cavitation and crazing causes degradation in mechanical properties, which eventually results in the permanent failure of the materials. This paper provides an overview of the principal approaches to assess and characterize damage in semi-crystalline polymers. The damage characterization methods are divided into two categories: mechanical characterization methods, aiming at describing damage growth based on the measurement of mechanical or physical properties and structural characterization methods, focusing on the assessment of microdamage initiation and evolution. Special attention has been paid to in situ non-destructive damage characterization methods. For better understanding deformation/damage behavior in semi-crystalline polymers, two major damage theories currently used to describe damage development are also described. The paper concludes with a discussion of limitations and critical issues for characterizing damage in semi-crystalline polymers.
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