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GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be about 93.28 seconds in August 2017, 93.22 seconds in February 2018, 93.25 seconds in June 2019 and 93.14 seconds in June 2020. GRO J1008-57 evolved in the spin-up process with a mean rate of − ( 2.10 ± 0.05 ) × 10−4 s/d from 2009 – 2018, and turned into a spin down process with a rate of ( 6.7 ± 0.6 ) × 10−5 s/d from Feb 2018 to June 2019. During the type II outburst of 2020, GRO J1008-57 had the spin-up torque again. During the torque reversals, the pulse profiles and continuum X-ray spectra did not change significantly, and the cyclotron resonant scattering feature around 80 keV was only detected during the outbursts in 2017 and 2020. Based on the observed mean spin-up rate, we estimated the inner accretion disk radius in GRO J1008-57 (about 1 - 2 times of the Alfven radius) by comparing different accretion torque models of magnetic neutron stars. During the spin-down process, the magnetic torque should dominate over the matter accreting inflow torque, and we constrained the surface dipole magnetic field B ≥ 6 × 10 12 G for the neutron star in GRO J1008-57, which is consistent with the magnetic field strength obtained by cyclotron line centroid energy.

Recently, the system parameters of Cygnus X-1, i.e., the black hole mass M, the orbital inclination i and the source distance D, have been updated. As the input constraints of the continuum-fitting method, it is necessary to refine the spin with these new parameters. The Hard X-ray Modulation Telescope (HXMT, also named Insight) was successfully launched on June 15th, 2017 in China. In this work, we analyzed spectra obtained by the Insight-HXMT during 2017-2018 and re-estimated the spin via the continuum-fitting method. We first re-estimated the spin using old parameters and found the dimensionless spin parameter to be a ⁎ > 0.934 (3σ), which is consistent with previous measurements both from the continuum-fitting and iron-line fitting methods ( Gou et al. 2011 , Gou et al. 2014 ; Fabian et al. 2012 , Walton et al. 2016 , Tomsick et al. 2018 ). Then, when the new parameters were applied, we obtained an increased spin: a ⁎ > 0.967 (3σ), which is also consistent with the recent measurement (Zhao et al. 2020, submitted to ApJ) and also confirms an extreme Kerr black hole lying in this system.

A new black hole X-ray binary (BHXRB) MAXI J1535-571 was discovered by MAXI during its outburst in 2017. Using observations taken by the first Chinese X-ray satellite, the Hard X-ray Modulation Telescope (dubbed as Insight-HXMT), we perform a joint spectral analysis (2-150 keV) in both energy and time domains. The energy spectra provide the essential input for probing the intrinsic Quasi-Periodic Oscillation (QPO) fractional rms spectra (FRS). Our results show that during the intermediate state, the energy spectra are in general consistent with those reported by Swift/XRT and NuSTAR. However, the QPO FRS become harder and the FRS residuals may suggest the presence of either an additional power-law component in the energy spectrum or a turn-over in the intrinsic QPO FRS at high energies.

We study the 2018 outburst of Aql X-1 via the monitor of all sky X-ray image (MAXI) data. We show that the outburst starting in February 2018 is a member of short-low class in the frame of outburst duration and the peak count rate although the outburst morphology is slightly different from the other fast-rise-exponential-decay (FRED) type outbursts with a milder rising stage. We study the partial accretion in the weak propeller stage of Aql X-1 via the MAXI data of the 2018 outburst. We report on the spectral analysis of 3 observations of Aquila X-1 obtained by Insight – hard X-ray modulation telescope (Insight-HXMT) during the late decay stage of the 2018 outburst. We discuss that the data taken by Insight-HXMT is just after the transition to the weak propeller stage. Our analysis shows the necessity of a comptonization component to take into account the existence of an electron cloud resulting photons partly up-scattered.

In this paper, thermal stability of Sn-0.7Cu-10B-xNi/Co (SCB-xNi/Co, x = 0.05, 0.10 and 0.15, in wt.%) interface during multiple reflows was investigated. Both (Ni,Co)Sn3 and (Cu,Ni)6Sn5 phases were formed at the SCB-xNi/Co interface after the initial reflow. With the increase of reflow number, the thermal stability of intermetallic compounds (IMCs) layer at high temperature was significantly different. The content of Ni atoms determined the thermal stability of IMCs layer in the interface reaction process. At the IMCs layer at the SCB-0.15Ni/Co interface, Ni atoms were enriched excessively, but they were present in a dispersive distribution at SCB-0.05Ni/Co and SCB-0.10Ni/Co interfaces. Ni atoms occupied sublattice sites of Co atoms in CoSn3 phase, which could improve the high-temperature stability of IMCs layer, so the IMCs layer had the strongest thermal stability at the SCB-0.15Ni/Co interface.

High energy X-ray telescope (HE) is one of the three instruments of Insight-HXMT (Hard X-ray Modulation Telescope) payload. The HE detector (HED) array is composed of 18 actively NaI(Tl)/CsI(Na) phoswich scintillators with a total geometric area of ∼ 5100 cm 2 and cover the energy range 20∼250 keV. In this paper we describe the on-ground detector-level calibration campaigns and present the principal instrument properties of HEDs.

The interface reaction between the Sn-0.7Cu-10Bi-0.15Co and Co substrate during multiple reflow cycles and the growth and evolution rhythm of intermetallic compounds (IMCs) were investigated. The results showed that as the reflow cycles increased in number, different growth morphologies and evolution rules of the IMCs layer including its primary growth, dissolution and secondary growth appeared. In the primary stage of multiple reflows, Co could be continuously diffused from the Co substrate to the IMCs/solder interface to provide enough Co for the growth of IMCs layer. As the IMCs layer became thick, the diffusion of Co to the interface was inhibited, and the dynamic equilibrium of IMCs growth was broken. When the growth rate was higher than the dissolution rate, the IMCs layer grew as a whole and whereas the IMCs were dissolved. And under the action of adsorption force, the dissolved IMCs particles re-aggregated and grew.

Bifurcations are employed when two or more branch pipes are merged into one main pipe, which generally located upstream of the powerhouse and embedded in surrounding media. A three dimension (3D) numerical model for the symmetrical Y-shape steel bifurcation with crescent rib embedded in in-situ cast concrete anchor block is developed, in which the water head is as high as 652 m. Then, by means of the point-to-point contact element of CONTAC52 simulating the initial gap between steel pipe and concrete, the resulting distribution of stress, settlement of bedrock are revealed. Further, a novel method to calculate the load bearing ratio of the concrete anchor block is proposed to evaluate the load-bearing capability of the surrounding concrete. Further, this study also discusses the effects of the initial gap, the concrete elastic modulus and the deformation modulus of the bedrock. The results demonstrate adequate rebar should be arranged to ensure the integrity of the anchor block and to limit the crack widths. The design criteria of reinforced concrete penstock are suggested for the detailed design of embedded bifurcations to simplify the construction process, to reduce the steel thickness of the steel bifurcation and the amount of investment.

Background Terrestrial Trunked Radio (TETRA) is used for radiocommunications among the British police forces. Objectives To investigate association of personal radio use and sickness absence among police officers and staff from the Airwave Health Monitoring Study. Methods Participant-level sickness absence records for 26 forces were linked with personal radio use for 32,102 participants. We used multivariable logistic regression to analyse TETRA usage in year prior to enrolment and sickness absence (lasting more than 7 or 28 consecutive days) in the following year and a zero-inflated negative binomial model for analyses of number of sickness absence episodes of any duration (‘spells’) over the same period. In secondary analyses, we looked at an extended period of observation among a sub-cohort with linked data over time, using Cox proportional hazards regression. Results Median personal radio use (year prior to enrolment) was 29.7 min per month (interquartile range 7.5, 64.7) among users. In the year following enrolment there were 25,655 sickness absence spells among 15,248 participants. There were similar risks of sickness absence lasting more than seven days among users and non-users, although among users risk was higher with greater use, odds ratio = 1.04 (95% confidence interval [CI] 1.02 to 1.06) per doubling of radio use. There was no association for sickness absence of more than 28 days. For sickness absence spells, risk was lower among users than non-users (incidence rate ratio = 0.91; 95% CI 0.75 to 1.11), again with higher risk among users for greater radio use. There was no association between radio use and sickness absence in secondary analyses. Discussion There were similar or lower risks of sickness absence in TETRA radio users compared with non-users. Among users, the higher risk of sickness absence with greater radio use may reflect working pattern differences among police personnel rather than effects of radiofrequency exposure.

The effect of Lactobacillus plantarum-fermentation on the anti-diabetic functionality of Momordica charantia was examined using a high-fat-diet and low-dose streptozocin-induced type 2 diabetic rat model. Fermented Momordica charantia juice (FMCJ) administration mitigated the hyperglycemia, hyperinsulinemia, hyperlipidemia, and oxidative stress in diabetic rats more favorably than the non-fermented counterpart. Treatments with FMCJ improved ergosterols and lysomonomethyl-phosphatidylethanolamines metabolisms more effectively. Supplement of FMCJ regulated the composition of the gut microbiota, such as increased the abundance of Bacteroides caecigallinarum, Oscillibacter ruminantium, Bacteroides thetaiotaomicron, Prevotella loescheii, Prevotella oralis, and Prevotella melaninogenica, in diabetic rats compared with untreated diabetic rats. Moreover, FMCJ-treated diabetic rats exhibited higher concentrations of acetic acid, propionic acid, butyric acid, total short-chain fatty acids and lower pH values in colonic contents than that in non-fermented juice-treated rats. These results demonstrated that Lactobacillus plantarum-fermentation enhanced the anti-diabetic property of MC juice by favoring the regulation of gut microbiota and the production of SCFAs.

The detection of the high-energy (∼290 TeV) neutrino coincident with the flaring blazar TXS 0506+056, the first and only 3σ neutrino-source association to date, provides new, multimessenger tests of the weak equivalence principle (WEP) and Lorentz invariance. Assuming that the flight time difference between the TeV neutrino and gamma-ray photons from the blazar flare is mainly caused by the gravitational potential of the Laniakea supercluster of galaxies, we show that the deviation from the WEP for neutrinos and photons is conservatively constrained to have an accuracy of 10 − 6 – 10 − 7 , which is 3–4 orders of magnitude better than previous results placed by MeV neutrinos from supernova 1987A. In addition, we demonstrate that the association of the TeV neutrino with the blazar flare sets limits on the energy scales of quantum gravity for both linear and quadratic violations of Lorentz invariance (LIV) to E QG , 1 > 3.2 × 10 15 – 3.7 × 10 16 GeV and E QG , 2 > 4.0 × 10 10 – 1.4 × 10 11 GeV. These improve previous limits on both linear and quadratic LIV energy scales in neutrino propagation by 5–7 orders of magnitude.

Momordica charantia L. has been consumed as a vegetable for thousands of years, and its fruit has various bioactive compounds. The aim of this study was to investigate the effect of fermentation with Lactobacillus plantarum (L. plantarum) NCU116 on the chemical composition, antioxidant activity, and volatile profile of M. charantia juice. Fermentation and sterilization increased the concentrations of short-chain fatty acids, while the total saponins in the juice was reduced. Fermentation increased lactic acid, total phenolics, and total flavonoids. Fermentation improved the phenolic composition of the juice, such as decreased caffeic and p-coumaric acids, and increased dihydrocaffeic and phloretic acids. Furthermore, the antioxidant properties of the juice and phenolic extracts increased after fermentation. Fermentation altered the aroma profile of the juice to confer a more desirable flavor by reducing aldehydes and ketones, while increasing alcohols and acids. Sterilization decreased lactic acid, total phenolic content, phenolic composition, antioxidant activities, and the aroma profile. These results suggested that L. plantarum fermentation had a beneficial effect on the physico-chemical properties, bioactive compounds, antioxidant property, as well as aroma composition of M. charantia.

This study focuses on the low-cycle fatigue issue of steel spiral cases (SSCs) in pumped-storage power plants considering their frequent operation-mode switches. First, a finite element (FE) analysis of a composite SSC-concrete structure was performed with an improved ABAQUS-based complete simulation procedure, which has been validated in the authors' previous work. Both low and high temporary internal water pressure (IWP) were considered following the China's and US's design philosophies, respectively. It has identified an association between the untimely and delayed gap-closing phenomenon and the high stresses in the SSC. Then the FE results were imported into the DesignLife software to carry out a fatigue analysis. The results show that the low-cycle fatigue issue of the SSC might not be totally out of the question even only considering routine operation-mode switching frequency of the pump-turbine set. The temporary IWP at different levels has a significant impact on the fatigue life of the SSC.

Accurately predicting the propagation of hydraulic fracturing arising from the wellbore is essential in petroleum engineering, hydraulic engineering, etc. There are various factors influencing fracture propagation, such as the initial fracture orientation and in-situ stresses, while the limitation of appropriate methods and techniques hinders the further investigation on the propagating mechanism. In the study, a simulator based on High-order Generalized Finite Element Method (GFEM) is introduced to investigate the propagation behaviors of hydraulic fractures arising from the sidewall of wellbore. For better recognization of hydraulic fracturing, several numerical examples are performed based on the simulator. Different influencing factors are studied, including intersection angle between fracture and wellbore, in-situ stresses and fracture interactions. It is found that, regardless of in-situ stresses in the surrounding rock, pre-existing fractures approximately propagate straightforward along their initial directions and finally form planar fracture surfaces. Regarding in-situ stresses, with acute intersection angle between fracture and wellbore, fractures propagate toward the direction of the minimum principal stress. Besides, two parallel and opposite fractures individually arising from two parallel and non-coincidence wellbores always propagate towards each other after passing by each other. Moreover, the interactions between them become strengthened as the distance between them decreases. Finally, the propagating sequences of hydraulic fractures arising from a group of parallel wellbores are discussed. It is found that the sequence can influence the fracture geometry and previously propagated fractures can restrain the nearest fractures embedded in other wellbores propagating away from each other in subsequent stages.

As one important component of smart world, smart health is drawing more and more attention. Over the years, hypertension has become a high incident disease and it is continuing to threaten human health seriously. Unfortunately, no effective way has been found to cure hypertension at present. Many medical experiences have demonstrated the curative effect of traditional Chinese medicine in the hypertension treatment. In this paper, we explore smart Chinese medicine for hypertension treatment by combining deep learning and the traditional Chinese medicine theory. First, we present a potential idea to categorize the clinical cases into different groups based on symptom with the stacked auto-encoder model. Furthermore, we discuss and summarize the curative effect of classical prescriptions and herbs for each type of symptom in hypertension. Finally, we review the related work about deep learning models in medical application. The explored smart Chinese medicine is expected to guide doctors to treat hypertension diseases in clinical, which is helpful to build smart world, especially smart health.

Numerical simulation has been widely used for predicting rock mass convergence during tunnel excavation. Considering that tunnel construction is a three-dimensional (3D) process, the 3D numerical analysis, instead of the plane-strain models, are commonly employed in engineering practice. As the 3D numerical analyses require large numbers of computational resources, the geometric extents are often kept to a minimum to reduce simulation time. However, there is a lack of published information concerning appropriate the size of numerical model. The study investigates how the transverse range of tunnel section, including the upper boundary, the lower boundary and the lateral boundary, affects the tunnel convergence via the finite difference software package FLAC3D, respectively. Then, a comprehensive function to yield the minimum transverse section area within a given error is proposed. After several cases with different categories of rock are employed in the simulations, the universal model extents with the minimum transverse section area are proposed.

Type 2 diabetes is a complex metabolic and endocrine disorder worldwide, which causes severe health and economic problems. The effects of polysaccharide from Plantago asiatica L. (PLP) on high-fat diet and streptozotocin-induced type 2 diabetic rats were examined. Administration of PLP caused significant decreases in the concentrations of blood glucose, insulin, total cholesterol, triglyceride, non-esterified fatty acid and maleic dialdehyde, and significant increases in the levels of high density lipoprotein-cholesterol and the activities of antioxidant enzymes compared with diabetic rats after 4 weeks’ treatment. The concentrations of short-chain fatty acids (SCFA) were significantly higher in the feces of diabetic rats after treatment with PLP. Moreover, colon bacterial diversity and abundance of bacteria, including Bacteroides vulgatus, Lactobacillus fermentum, Prevotella loescheii and Bacteroides vulgates were significantly increased by PLP treatment. These results indicated that the anti-diabetic effect of PLP in type 2 diabetic rats may be associated with regulation of gut microbiota and increased levels of SCFA.