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The observation of a massive galaxy with an extremely low dark matter content (i.e. NGC 1277) has posed questions about how such objects form and evolve in a hierarchical universe. We here report on the finding of several massive, dark matter-deficient galaxies in a set of 324 galaxy clusters theoretically modelled by means of full-physics hydrodynamical simulations. We first focus on two example galaxies selected amongst the most massive and dark matter-deficient ones. By tracing the evolution of these galaxies, we find that their lack of dark matter is a result of multiple pericentre passages. While orbiting their host halo, tidal interactions gradually strip away dark matter while preserving the stellar component. A statistical analysis of all massive satellite galaxies in the simulated clusters shows that the stellar-to-total mass ratio today is strongly influenced by the number of orbits and the distance at pericentres. Galaxies with more orbits and closer pericentres are more dark matter-deficient. Additionally, we find that massive, dark matter-deficient galaxies at the present day are either the remnants of very massive galaxies at infall or former central galaxies of infalling groups. We conclude that such massive yet dark matter-deficient galaxies exist and are natural by-products of typical cluster galaxy evolution, with no specific requirement for an exotic formation scenario. [ABSTRACT FROM AUTHOR]

The unique characteristics of the brightest group galaxies (BGGs) serve as a link in the evolutionary continuum between galaxies such as the Milky Way and the more massive brightest cluster galaxies found in dense clusters. This research investigates the evolution of the stellar properties of BGGs over cosmic time (z = 0.08 − 1.30), extending the work from our prior studies. We analyzed the data of 246 BGGs selected from our X-ray galaxy group catalog within the COSMOS field, examining stellar age, mass, star-formation rate (SFR), specific SFR, and halo mass. We compared observations with the Millennium and Magneticum simulations. Additionally, we investigated whether stellar properties vary with the projected offset from the X-ray peak or the hosting halo center. We evaluated the accuracy of SED-derived stellar ages using a mock galaxy catalog, finding a mean absolute error of around 1 Gyr. Interestingly, the observed BGG age distributions exhibit a bias toward younger intermediate ages compared to both semi-analytical models and the Magneticum simulation. Our analysis of stellar age versus mass unveils intriguing trends with a positive slope, hinting at complex evolutionary pathways across redshifts. We observed a negative correlation between stellar age and SFR across all redshift ranges. We employed a cosmic time dependent main sequence framework to identify star forming BGGs and find that approximately 20% of BGGs in the local universe continue to exhibit characteristics typical of star forming galaxies, with this proportion increasing to 50% at z = 1.0. Our findings support an inside-out formation scenario for BGGs, where older stellar populations reside near the X-ray peak and younger populations at larger offsets indicate ongoing star-formation. The observed distribution of stellar ages, particularly for lower-mass BGGs in the range of 1010−11 M⊙, deviates from the constant ages predicted by the models across all stellar mass ranges and redshifts. This discrepancy aligns with the current models' known limitations in accurately capturing galaxies' complex star-formation histories. [ABSTRACT FROM AUTHOR]

The increasing application of virtual surgical planning (VSP) in orthognathic surgery implies a critical need for accurate prediction of facial and skeletal shapes. The craniofacial relationship in patients with dentofacial deformities is still not understood, and transformations between facial and skeletal shapes remain a challenging task due to intricate anatomical structures and nonlinear relationships between the facial soft tissue and bones. In this study, a novel bidirectional 3-dimensional (3D) deep learning framework, named P2P-ConvGC, was developed and validated based on a large-scale data set for accurate subject-specific transformations between facial and skeletal shapes. Specifically, the 2-stage point-sampling strategy was used to generate multiple nonoverlapping point subsets to represent high-resolution facial and skeletal shapes. Facial and skeletal point subsets were separately input into the prediction system to predict the corresponding skeletal and facial point subsets via the skeletal prediction subnetwork and facial prediction subnetwork. For quantitative evaluation, the accuracy was calculated with shape errors and landmark errors between the predicted skeleton or face with corresponding ground truths. The shape error was calculated by comparing the predicted point sets with the ground truths, with P2P-ConvGC outperforming existing state-of-the-art algorithms including P2P-Net, P2P-ASNL, and P2P-Conv. The total landmark errors (Euclidean distances of craniomaxillofacial landmarks) of P2P-ConvGC in the upper skull, mandible, and facial soft tissues were 1.964 ± 0.904 mm, 2.398 ± 1.174 mm, and 2.226 ± 0.774 mm, respectively. Furthermore, the clinical feasibility of the bidirectional model was validated using a clinical cohort. The result demonstrated its prediction ability with average surface deviation errors of 0.895 ± 0.175 mm for facial prediction and 0.906 ± 0.082 mm for skeletal prediction. To conclude, our proposed model achieved good performance on the subject-specific prediction of facial and skeletal shapes and showed clinical application potential in postoperative facial prediction and VSP for orthognathic surgery. [ABSTRACT FROM AUTHOR]

In the development and construction of the power grid, the transmission line corridor inevitably passes through the area with dense vegetation. Forest fires are common in the dry season, seriously affecting the normal operation of the transmission line. Due to the sharp increase in air temperature and a large amount of smoke during combustion, the steel-core aluminum strand without a sheath is directly exposed to the air of the fire field. Due to the high temperature and adhesion, the structure of the wire changes and the tensile strength decreases accordingly, which can lead to serious damage to the wire, including broken strands and fractures, and it can no longer be used. To solve the problem that it is difficult to assess the operational characteristics of transmission lines after a fire, the mechanical characteristics of transmission lines under forest fire conditions are studied through theory and simulation so that the mechanical characteristics of transmission lines after a forest fire can be quantitatively expressed. It is proposed that a mechanical design manual for conductors under mountain fire conditions be created and the online monitoring system for transmission conductors under mountain fire conditions be improved. [ABSTRACT FROM AUTHOR]

The determination of the mass of galaxy clusters from observations is subject to systematic uncertainties. Beyond the errors due to instrumental and observational systematic effects, in this work we investigate the bias introduced by modelling assumptions. In particular, we consider the reconstruction of the mass of galaxy clusters from convergence maps employing spherical mass density models. We made use of THE THREE HUNDRED simulations, selecting clusters in the same redshift and mass range as the NIKA2 Sunyaev-Zel'dovich Large Programme sample: 3 ≤ M500/1014 M⊙ ≤ 10 and 0.5 ≤ z ≤ 0.9. We studied different modelling and intrinsic uncertainties that should be accounted for when using the single cluster mass estimates for scaling relations. We confirm that the orientation of clusters and the radial ranges considered for the fit have an important impact on the mass bias. The effect of the projection adds uncertainties to the order of 10–16% to the mass estimates. We also find that the scatter from cluster to cluster in the mass bias when using spherical mass models is less than 9% of the true mass of the clusters. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to determine the changing prevalence of five chronic non-communicable diseases (NCDs)- hypertension, coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), and asthma— and its multimorbidity (refers to the co-existence of two or more chronic diseases in an individual) across socioeconomic spectra in rural southwest China. Measurements: Two cross-sectional health interviews and examination surveys were conducted among individuals aged ≥35 years in rural China. An individual socioeconomic position (SEP) index was constructed using principal component analysis. Anthropometric measurements, blood pressure, and post-bronchodilator spirometry tests were recorded for each participant. Results: The mean age and proportion of men was 56.1 years and 48.4% in 2011, while was 56.6 years and 49.4% in 2021. From 2011 to 2021, the overall prevalence of hypertension, stroke and COPD increased from 26.1%, 1.1%, and 8.7% to 40.4%, 2.4%, and 12.8%, respectively (P < 0.01), while prevalence of CHD (2.1% vs. 2.2%) and asthma (1.4% vs. 1.5%) did not differ between the two study years (P > 0.05). The prevalence of NCDs multimorbidity increased from 2.3% to 9.7%, and was also observed among subgroups categorized by sex, age, ethnicity, level of education, income, and SEP (P < 0.01). In addition, the relative increases in the prevalence of multimorbidity were greater among men, old individuals, ethnic minorities, and those with low level of education and low SEP. Both in 2011 and 2021, ethnic minorities and individuals with lower level of education and low SEP had a higher prevalence of multimorbidity of the five studied chronic NCDs than their counterparts (P <0.01). Conclusions: The prevalence of NCDs multimorbidity increased substantially across all socioeconomic gradients in rural southwest China. Future interventions to further manage NCDs and their multimorbidity must be tailored to address socioeconomic factors. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new large-scale change detection dataset called LIM-CD, designed for training and evaluating change detection algorithms on high resolution remote sensing images. The dataset currently consists of 9,259 images with labels covering six construction land use change types (i.e., residential land, industrial land, commercial land, public facilities, transportation land, and special land). The image annotations contain not only newly added regions of construction land as change annotations but also auxiliary information about construction land present in pre-change image (image T1), which serves as secondary annotations. These annotations offer crucial information for incremental monitoring applications. The remote sensing images are carefully selected to cover a broad range of imaging variations, including different image sources, years, backgrounds, and terrain. Additionally, we have provided comprehensive metadata labels, which can serve as additional features to aid model training and optimization. To establish a baseline for future algorithm development, we applied seven widely used and state-of-the-art change detection algorithms to the LIM-CD dataset. We are confident that our dataset can serve as a valuable resource for the research community, enabling the development of more accurate and robust change detection models. More information about the project can be found at https://github.com/xiaoxiangAQ/LIM-CD-dataset. [ABSTRACT FROM AUTHOR]

This study aimed to explore the mechanism of Qingre Huoxue Fang (QRHXF) treatment on anti-angiogenesis in rheumatoid arthritis (RA) based on network pharmacology and in vitro experiments. We used the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Therapeutic Target (TTD) database to extract the active components of QRHXF and potential targets for regulating angiogenesis. First, we used Cytoscape bioinformatics software to construct the network of QRHXF-angiogenesis and screened the potential targets. Then, we performed gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis on the potential core targets. In addition, enzyme-linked immune assay and Western blot were used for in vitro validation and to verify the effects of different concentrations of QRHXF on the expression levels of the vascular endothelial growth factor receptor type 1 (VEGFR-1) and VEGFR-2 cytokines and phosphoinositide 3-kinase (PI3k) and Ak strain transforming (Akt) proteins in human umbilical vein endothelial cells (HUVECs). In results, we screened 179 core QRHXF antiangiogenic targets, including vascular endothelial growth factor (VEGF) cytokines. Enrichment analysis showed that the targets were enriched in 56 core signaling pathways, including PI3k and Akt. In vitro experiments showed that the migration distance and square, adhesion optical density (OD) values, and the number of branch points in tube formation significantly decreased in the QRHXF group compared with the induced group (P<0.01). Notably, the serum levels of VEGFR-1 and VEGFR-2 were lower compared with the induced group (P<0.05 or P<0.01). In addition, the expressions of PI3K and p-Akt proteins were decreased in the middle- and high doses groups (P<0.01). This study's results suggest that the downstream mechanism of QRHXF anti-angiogenesis might inhibit the PI3K-Akt signaling pathway and downregulate VEGF-1 and VEGF-2. [ABSTRACT FROM AUTHOR]

Soft X-ray emissions induced by solar wind ions that collide with neutral material in the solar system have been detected around planets, and were proposed as a remote probe for solar wind interaction with the Martian exosphere. A multi-fluid three-dimensional magnetohydrodynamic model is adopted to derive the global distributions of solar wind particles. Spherically symmetric exospheric H, H2, He, O, and CO2 density profiles and a sophisticated hybrid model that includes charge-exchange and proton–neutral excitation processes are used to study the low triplet line ratio G = i + f r (0.77 ± 0.58) of O vii and the total X-ray luminosity around Mars. We further calculate the emission factor α -value with different neutrals over wide ion-abundance and velocity ranges. Our results are in good agreement with those of previous reports. The evolution of the charge stage of solar wind ions shows that sequential recombination due to charge-exchange can be negligible in the interaction region. This only appears below an altitude of 400 km. The anonymous low disk G- ratio can be easily explained by the collisional quenching effect at neutral densities higher than 1011 cm−3. However, the quenching contribution is small in Mars' exosphere and only appears below 400 km. Charge-exchange with H2 and N2 is still the most likely reason for this low G -ratio. X-ray emissivity maps in collisions with different neutrals differ from each other. A clear bow shock arising from the collision with all the neutrals is in accordance with previous reports. The resulting total X-ray luminosity of 6.55 MW shows better agreement with the XMM-Newton observation of 12.8 ± 1.4 MW than that of previous predictions. [ABSTRACT FROM AUTHOR]

Kernel structure-related traits are important factors that affect the yield and ear appearance of waxy corn (Zea mays L. var. ceratina), regulated together by genetic factors and cultivation practices. Two planting densities, 52500 plants/ha and 67500 plants/ha, were established in this study for three major cultivars that are promoted in the local region: Jinnuo 18# (JN18), Jinnuo 20# (JN20), and Jindannuo 41# (JdN41). We measured how the kernel length, width, thickness, volume, 100-kernel weight, and kernel weight of different parts of the waxy corn ear changed with planting density and cultivar. The results showed that planting density did not significantly affect the structure-related traits of kernels in different parts of the waxy corn ear. Most of the kernel structure-related traits in the middle and basal parts were significantly higher than those in the apical part of the waxy corn ear. Compared with planting density, cultivar had a greater influence on kernel structure-related traits in waxy corn. Comparison between different cultivars showed that the kernel structure-related traits in JN18 were better than those in JdN41. [ABSTRACT FROM AUTHOR]

We search for the signature of cosmological shocks in stacked gas pressure profiles of galaxy clusters using data from the South Pole Telescope (SPT). Specifically, we stack the latest Compton- y maps from the 2500 deg2 SPT-SZ survey on the locations of clusters identified in that same data set. The sample contains 516 clusters with mean mass |$\langle M_{\rm 200m}\rangle = 10^{14.9} \, {\rm M}_\odot$| and redshift 〈 z 〉 = 0.55. We analyse in parallel a set of zoom-in hydrodynamical simulations from the three hundred project. The SPT-SZ data show two features: (i) a pressure deficit at R / R 200m = 1.08 ± 0.09, measured at 3.1σ significance and not observed in the simulations, and; (ii) a sharp decrease in pressure at R / R 200m = 4.58 ± 1.24 at 2.0σ significance. The pressure deficit is qualitatively consistent with a shock-induced thermal non-equilibrium between electrons and ions, and the second feature is consistent with accretion shocks seen in previous studies. We split the cluster sample by redshift and mass, and find both features exist in all cases. There are also no significant differences in features along and across the cluster major axis, whose orientation roughly points towards filamentary structure. As a consistency test, we also analyse clusters from the Planck and Atacama Cosmology Telescope Polarimeter surveys and find quantitatively similar features in the pressure profiles. Finally, we compare the accretion shock radius (⁠|$R_{\rm sh,\, acc}$|⁠) with existing measurements of the splashback radius (R sp) for SPT-SZ and constrain the lower limit of the ratio, |$R_{\rm sh,\, acc}/R_{\rm sp}\gt 2.16 \pm 0.59$|⁠. [ABSTRACT FROM AUTHOR]

To limit the growth of oxides with low electrical conductivity and to suppress the inter-diffusion of elements between coating and substrate, an additional CrN sublayer is pre-deposited by arc ion plating. The Mn/Cu layers are electrodeposited in an aqueous solution. The results show that the CrN layer is about 2 µm and decomposes rapidly at 750 °C, and only Cr2N and Cr2O3 are detected after 1 h. The inner layer of Cr2N is not entirely decomposed after 100 h, and little Fe from the substrate diffuses into the CrN layer. When Mn/Cu-coated 430 stainless steel (SS) oxidized for 10 h, a mass of Fe-rich oxides are found in the oxide layer. For Mn/Cu/CrN-coated 430 SS, Cr2O3 and Cr2N bilayer structure and an internal oxidation zone containing some gaseous nitrogen are found near the interface. After oxidation for 10 h, area-specific resistance (ASR) of Mn/Cu-coated 430 SS is the smallest among the three oxide coatings. The ASR of the CrN layer and Mn/Cu/CrN layer oxidized for 10 h is very high. After 100 h, a part of Cr2N is oxidized into the Cr2O3 layer, and the ASR of the CrN layer decreases. [ABSTRACT FROM AUTHOR]

We present an X-ray spectrum of the diffuse X-ray background (DXRB) between 1.5 and 120 keV, as measured with the Low-Energy Detector (LE) and the High-Energy Detector (HE) aboard the Insight-HXMT satellite, based on 'blank-sky' observations. LE covers a nominal energy range of 1–15 keV and HE 20–250 keV, but calibration issues and data quality narrowed the energy range for this work. The LE background was directly measured with 'blind' detector modules, while the HE background was derived from Earth-occultation data. With the LE data alone, the measured DXRB spectrum can be well-described by a power law; fitting the LE and HE data jointly, however, a spectral cut-off must be introduced in the model to account for the measurements above 30 keV. Modelling the combined spectrum with a cut-off power law, the best-fitting photon index is 1.40, normalization 9.57  |$\rm ph~cm^{-2}\,s^{-1}\,keV^{-1}\,sr^{-1}$| (at 1 keV), and cut-off energy 55 keV after correcting for the effects of the Earth albedo and atmospheric emission (which are significant in the HE band). Based on the best-fitting cut-off power law, we derived the spectral energy distribution (SED) of the DXRB. The shape of the SED is in general agreement with the published measurements, but the overall normalization is lower by varying amounts, except for the HEAO-1 result, with which our result is in good agreement. [ABSTRACT FROM AUTHOR]

Background and Purpose: SIRT1 was associated with AS risk and EPCs were reported to participate in the endothelial repair in Coronary Atherosclerosis (CAS). In this study, we explored the role of SIRT1 in AS mice and also its modulation in EPCs. Methods and Materials: ApoE−/−mice were fed on high-fat and high-glucose diet to establish the AS animal model with the normally-raised C57BL/6 mice as a control group. SIRT1 activator, SRT 2104 was injected intravenously into 5 ApoE−/−mice and its inhibitor Nicotinamide was injected in tail in another 5 ApoE−/− mice. Weight changes were recorded. Blood samples were taken from posterior orbital venous plexus and were detected by automatic biochemical analyzer. HE staining displayed the pathological conditions while Immunohistochemistry (IHC) evaluated the CD34+/VEGFR2+ relative density in the aorta tissues. EPCs were isolated from bone marrow and verified using immunofluorescence staining (IFS). The modulatory mechanism of SIRT1 in EPCs were studied by using RT-PCR, MTT, Western Blot and colony formation, scratch methods. Results: SIRT1 activator negatively regulated the weight and TC, TG and LDL levels, alleviated the lesion conditions and decreased the CD34+/VEGFR2+ density compared to the AS control. In vitro, SIRT1 activator promoted the proliferation and migration of EPCs and activated wnt/β-catenin/GSK3β signaling pathway. SIRT1 activator also inhibited the autophagy biomarkers ATG1 and LC3II. Furthermore, inhibitor of autophagy promoted SIRT1 expression and induced EPC proliferation, migration and activated wnt/β-catenin/GSK3β pathway. The suppression of the wnt/β-catenin/GSK3β pathway inhibited SIRT1 expression in EPCs, attenuated the proliferation and migration and promoted autophagy of EPCs. Conclusion: SIRT1 activation might be protective in AS mice through autophagy inhibition in EPCs via wnt/β-catenin/GSK3β signaling pathway. [ABSTRACT FROM AUTHOR]

Asymmetric responses of aboveground net primary productivity (ANPP) to precipitation were identified as a signal to predict ecosystem state shifts at temperate grassland zones in Inner Mongolia, China. However, mechanism studies were still lacking. This study hypothesized that the enhanced growth and newly emerged herbaceous after increased precipitation resulted in the highest asymmetry at the transition zone between desert and typical steppe. We monitored the responses of the normalized difference vegetation index (NDVI) of different species to precipitation events using un-manned aerial vehicle technology to test this hypothesis. NDVI and species richness were measured twice at fixed points in July and August with a time interval of 15 days. Results showed that: (1) From July to August, NDVI in the transition zone increased significantly after precipitation (P < 0.05), but NDVI in both the desert and typical steppe showed a non-significant change (P > 0.05). (2) In the transition zone, NDVI increases from the shrub and herbaceous contributed to 37 and 63% increases of the site NDVI, respectively. (3) There was a significant difference in species richness between July and August in the transition zone (P < 0.05), mainly caused by the herbaceous (Chenopodiaceae, Composite, Convolvulaceae, Gramineae, Leguminosae, and Liliaceae), which either emerged from soil or tillers growth from surviving plants. This study demonstrated that herbaceous dominant the changes of NDVI in the transition zone, which provides a scientific basis for the mechanism studies of ANPP asymmetric response to precipitation and warrants long-term measurements. [ABSTRACT FROM AUTHOR]

Charge exchange has been recognized as a primary source of soft X-ray emission in many astrophysical outflow environments, including cometary and planetary exospheres impacted by the solar wind. Some models have been set up by using different data collections of charge-exchange cross-sections. However, multiple-electron transfer has not been included in these models. In this paper, we set up a charge-exchange model with the inclusion of double-electron capture (DEC), and make a detailed investigation of this process on X-ray emissions of highly charged carbon, nitrogen, oxygen, and neon ions by using available experimental cross-sections. We also study the effect of different n- selective cross-sections on soft X-ray emission by using available experimental n -distributions. This work reveals that DEC enhancement on line intensity is linearly proportional to the ratio of ion abundance in the solar wind. It is more obvious for soft X-rays from carbon ions (C4+) in collision with CO2, and the enhancement on line intensity can be up to 53 per cent with typical ion abundances [ Advanced Composition Explorer (ACE)] in the solar wind. The synthetic spectra with parameters from the Ulysses mission for the solar wind reveal velocity dependence, target dependence, as well as the non-negligible contribution from the DEC. [ABSTRACT FROM AUTHOR]

We report on analysis of observations of the bright transient X-ray pulsar (XRP) Swift  J0243.6+6124 obtained during its 2017–2018 giant outburst with Insight-HXMT, NuSTAR , and Swift observatories. We focus on the discovery of a sharp state transition of the timing and spectral properties of the source at super-Eddington accretion rates, which we associate with the transition of the accretion disc to a radiation pressure dominated state, the first ever directly observed for magnetized neutron star. This transition occurs at slightly higher luminosity compared to already reported transition of the source from sub- to supercritical accretion regime associate with onset of an accretion column. We argue that this scenario can only be realized for comparatively weakly magnetized neutron star, not dissimilar to other ultra-luminous X-ray pulsars, which accrete at similar rates. Further evidence for this conclusion is provided by the non-detection of the transition to the propeller state in quiescence which strongly implies compact magnetosphere and thus rules out magnetar-like fields. [ABSTRACT FROM AUTHOR]

Given the severe waste of cold work moulds in the small batch production stage, a low cost 45 steel surface laser cladding Fe901 coating was proposed to replace cold work mould steel in this stage. Combining with the performance requirements of moulds, the laser cladding process parameters were optimized with the coating surface hardness as the goal. The optimized process parameters were laser power, powder feeding rate and scanning speed. 20 runs of cladding tests were carried out based on the central composite design method. Using Design-Expert software, the hardness-process parameter objective function model was obtained, and the reliability of the model was verified. The cladding process parameters were optimized based on the response surface method. It was found that the optimal ranges of laser power were 1600 to 2100 W, scanning speed were 9.5 to 13.0 mm/s and powder feeding rate were 24.0 to 34.0 g/min. This conclusion showed that the coating could reach the hardness index of cold work die steel. [ABSTRACT FROM AUTHOR]

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 Insightâˆ'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 1â€"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. [ABSTRACT FROM AUTHOR]

The effect of Sr concentration on the planar Hall effect (PHE) in epitaxial magnetic phase separated La1- x Sr x CoO3 (0.07 ⩽ x ⩽ 0.60) thin films was studied systematically. It was found that crystalline anisotropy and spin-orbital coupling are the main contributions to the unexpected fourfold symmetric PHE. The uniaxial anisotropy field was given by Huni = 70 Oe and cubic anisotropic field Hcub = 143 Oe, respectively. The magnetic anisotropy was weakened by Sr doping, which corresponds with the disappearance of the fourfold symmetry in PHE with the increasing Sr concentration. The first principle calculations proved that the contribution of Co-d orbitals to the magnetic anisotropy strongly depends on the Sr concentration. eg-dx2-y2 and eg-d3z2-r2 orbitals play a dominant role in the magnetic anisotropy of the samples with x = 0.125, 0.25, while the t2g-dxy, dyz, dxz orbitals contribute mainly to the magnetic anisotropy of the samples with x = 0.375, 0.5, 0.625. [ABSTRACT FROM AUTHOR]

Two types of Fe-based coatings (Specimen 1 and Specimen 2) were fabricated on a 45 steel by laser cladding with a high power diode laser (HPDL). The microstructure, phase composition and microhardness of the different coatings were investigated and the wear resistance was analysed. The results showed that the bottom, middle and upper parts of the clad layers exhibited different microstructures: the dominant phases of both specimens were α-Fe martensite and Cr23C6 hard phase. The two Fe-based coatings were also compared to a Cr12MoV die steel. the microhardness of Specimen 1 was significantly higher than that of the Cr12MoV die steel. The presence of the Cr23C6 hard phase in the clad layers of Specimen 1 and Specimen 2 reduced the wear weight loss and the width and depth of the wear scars compared with the Cr12MoV die steel. [ABSTRACT FROM AUTHOR]

In this paper, we presented a detailed timing analysis of a prominent outburst of 4U 0115+63 detected by Insight -HXMT in 2017 August. The spin period of the neutron star was determined to be 3.613 98 ± 0.000 02 s at MJD 57978. We measured the period variability and extract the orbital elements of the binary system. The angle of periastron evolved with a rate of |$0.048^\circ \pm 0.003^\circ \rm \, yr^{-1}$|⁠. The light curves are folded to sketch the pulse profiles in different energy ranges. A multipeak structure in 1–10 keV is clearly illustrated. We introduced wavelet analysis into our data analysis procedures to study quasi-periodic oscillation (QPO) signals and perform a detailed wavelet analysis in many different energy ranges. Through the wavelet spectra, we report the discovery of a QPO at the frequency of ∼10 mHz. In addition, the X-ray light curves showed multiple QPOs in the period of ∼16–32 and ∼67–200 s. We found that the ∼100 s QPO was significant in most of the observations and energies. There exist positive relations between X-ray luminosity and their Q-factors and S-factors, while the QPO periods have no correlation with X-ray luminosity. In wavelet phase maps, we found that the pulse phase of ∼67–200 s QPO is drifting frequently while that of ∼16–32 s QPO is scarcely drifting. The dissipation of oscillations from high energy to low energy was also observed. These features of QPOs in 4U 0115+63 provide a new challenge to our understanding of their physical origins. [ABSTRACT FROM AUTHOR]

The epitaxial CrxFe3-xO4 films were fabricated by dc reactive sputtering on MgO (001) substrates. The longitudinal resistivity ρxx was enhanced 3 orders of magnitude with the increase of Cr content x from 0 to 0.87. The tunneling magnetoresistance like planar Hall effect in the CrxFe3-xO4 films was observed while the angle between (100) in (001) oriented films and the direction of magnetic field is 45° and 135°, respectively. Both the phase relation of angular dependent planar Hall resistivity ρxy and the numeral relation of ρxy with longitudinal resistivity difference ρ// - ρ⊥ cannot be understood by the planar Hall effect expression in isotropic magnetic medium. The largest planar Hall resistivity was ~105 µΩ cm for x = 0.71, which is one, two, and six orders of magnitude larger than that in Fe3O4, GaMnAs, and ferromagnetic metals, respectively. The giant planar Hall resistivity ρxy is weak saturated at high fields and increases with the magnetic field. This giant planar Hall effect in the highly resistive CrxFe3-xO4 films is closely correlated to the longitudinal resistivity and antiphase boundaries. [ABSTRACT FROM AUTHOR]

Highly conductive (∼105 μΩ cm) Mn doped epitaxial Fe3O4 films were fabricated by reactive sputtering. The larger size of magnetic domains compared to grain size with the increasing Mn content indicates that the partial antiferromagnetic coupling across the antiphase boundaries has been weakened, which was further demonstrated by the smaller exchange bias, faster saturated magnetization, and decreasing exchange interaction JAF. The decrease of antiferromagnetic strength originates from the larger Mn-O bond length than that of Fe-O bond. The first-principle calculation shows that the half-metallic feature (100% spin polarization) of Fe3O4 was unchanged with the incorporation of Mn atoms. [ABSTRACT FROM AUTHOR]

We compare the statistics and morphology of giant arcs in galaxy clusters using N -body and non-radiative SPH simulations within the standard cold dark matter (CDM) model and simulations where dark matter (DM) has a non-negligible probability of interaction (parametrized by its cross-section), i.e self-interacting dark matter (SIDM). We use a ray-tracing technique to produce a statistically large number of arcs around six simulated galaxy clusters at different redshifts. Since DM is more likely to interact in colliding clusters than in relaxed clusters, and this probability of interaction is largest in denser regions, we focus our analysis on radial arcs (which trace the lensing potential in the central region better than tangential arcs) in galaxy clusters that underwent (or are undergoing) a major merger. We find that SIDM produces fewer radial arcs than standard CDM but they are on average more magnified. We also appreciate differences in the arc morphology that could be used to statistically favour one model versus the other. [ABSTRACT FROM AUTHOR]

We study the dependence of total secondary electron yield (SEY) of micro-porous silver surface on incident angle of primary electron. First, we produce regular and random micro-porous surfaces on silver plated aluminium samples by photolithography pattern process and direct chemical etching method, respectively. Second, we study the dependence of the SEY characteristics of these surfaces on the primary electron incident angle from 0° to 60°. The experimental results show that micro-porous surface with large porosity can suppress SEY effectively either for normal incidence or oblique incidence. The maximum SEY of the directly chemical etched sample can reach a 45% reduction relative to the original flat sample. We also show the anomalous experimental phenomenon that the SEY of directly chemical etched sample with large porosity does not increase with incident angle. Third, we explain the complicated SEY dependence on incident angle qualitatively by the secondary electron trapping effect in micro-pores as well as the Monte Carlo simulation based on phenomenological model of secondary electron emission. Finally, we suggest a third order polynomial formula to describe the SEY dependence on incident angle which will be useful in particle simulation. In total, we demonstrate that micro-porous surface with large porosity is effective in SEY suppression under both normal and oblique incidence and thus the proposed direct chemical etching method is prospective in related areas such as multipactor improvement. [ABSTRACT FROM AUTHOR]

Chlorophenol compounds have received widespread attention because of their sources, applications and characteristics. As an important environmental medium, suspended particles are ubiquitously distributed in aquatic ecosystems. In order to investigate the occurrence of chlorophenol compounds in aquatic environments of China and their toxicity in the case of suspended particles, literature retrieval methods were used to analyze their presence in waters, sediments and organisms in China and the effect of suspended particles on their toxicity to aquatic organisms was also investigated. The results showed that pentachlorophenol (PCP) or NaPCP present ubiquitous pollution and distributions in various aquatic environments. Meanwhile, in order to better protect human health and aquatic organisms, considering the effects of suspended particles on toxicity of these chemicals towards aquatic organisms, appropriate standards for chlorophenols were needed. [ABSTRACT FROM AUTHOR]

Current and future cosmological surveys are targeting star-forming galaxies at z ∼ 1 with nebular emission lines. We use a state-of-the-art semi-analytical model of galaxy formation and evolution to explore the large-scale environment of star-forming emission line galaxies (ELGs). Model ELGs are selected such that they can be compared directly with the DEEP2, VVDS, eBOSS-SGC, and DESI surveys. The large-scale environment of the ELGs is classified using velocity–shear–tensor and tidal–tensor algorithms. Half of the model ELGs live in filaments and about a third in sheets. Model ELGs that reside in knots have the largest satellite fractions. We find that the shape of the mean halo occupation distribution of model ELGs varies widely for different large-scale environments. To interpret our results, we also study fixed number density samples of ELGs and galaxies selected using simpler criteria, with single cuts in stellar mass, star formation rate, and [O  ii ] luminosity. The fixed number density ELG selection produces samples that are close to L[O  ii ] and SFR-selected samples for densities above 10−4.2  h 3 Mpc−3. ELGs with an extra cut in stellar mass applied to fix their number density, present differences in sheets and knots with respect to the other samples. ELGs, SFR, and L[O  ii ] selected samples with equal number density have similar large-scale bias but their clustering below separations of 1 h −1 Mpc is different. [ABSTRACT FROM AUTHOR]

We revisit the diagonal ridge feature (diagonal distributions in the R, vϕ plane) found in Gaia and present a timing analysis for it between Galactocentric distances of R = 7.5 and 12 kpc, using main-sequence turnoff and OB stars selected from the LAMOST Galactic spectroscopic surveys. We recover the ridge pattern in the R–vϕ plane color coded by mean radial velocity and find that this feature is presented from very young (OB stars, few hundred megayears) to very old populations (τ = 9–14 Gyr). Meanwhile, some ridge features are also revealed in the metallicity [Fe/H], [α/Fe], and vz distributions. In the LZ, vϕ plane, one of the ridge patterns, with constant angular momentum per unit mass, shows variations with different age populations compared. However, the remaining two are relatively stable, implying there might be two kinds of ridge patterns with different dynamical origins and evolutions. [ABSTRACT FROM AUTHOR]

Context. A link has finally been established between magnetars and fast radio burst (FRB) sources. Within this context, a major issue that remains unresolved pertains to whether sources of extragalactic FRBs exhibit X/γ-ray outbursts and whether this is correlated with radio activity. If so, the subsequent goal is to identify these sources. Aims. We aim to constrain possible X/γ-ray burst activity from one of the nearest extragalactic FRB sources currently known. This is to be done over a broad energy range by looking for bursts over a range of timescales and energies that are compatible with those of powerful flares from extragalactic magnetars. Methods. We followed up on the observation of the as-yet nearest extragalactic FRB source, located at a mere 149 Mpc distance, namely, the periodic repeater FRB 180916.J0158+65. This took place during the active phase between 4 and 7 February 2020, using the Insight–Hard X-ray Modulation Telescope (Insight–HXMT). By taking advantage of the combination of broad-band wavelengths, a large effective area, and several independent detectors at our disposal, we searched for bursts over a set of timescales from 1 ms to 1.024 s with a sensitive algorithm that had been previously characterised and optimised. Moreover, through simulations, we studied the sensitivity of our technique in the released energy-duration phase space for a set of synthetic flares and assuming a range of different energy spectra. Results. We constrain the possible occurrence of flares in the 1−100 keV energy band to E <  1046 erg for durations Δ t <  0.1 s over several tens of ks exposure. Conclusions. We can rule out the occurrence of giant flares similar to the ones that were observed in the few cases of Galactic magnetars. The absence of reported radio activity during our observations prevents us from making any determinations regarding the possibility of simultaneous high-energy emission. [ABSTRACT FROM AUTHOR]

Purpose: Laparoscopic high ligation of the internal inguinal ring is an alternative procedure for treatment of pediatric inguinal hernia (PIH), with a major trend toward increasing use of extracorporeal knotting and decreasing use of working ports. We have utilized this laparoscopic technique to treat the entire spectrum of PIH (including incarcerated cases) for more than 17 years, and the technique continues to evolve and improve. We herein report our latest modification of this minimally invasive technique, namely single-site laparoscopic percutaneous extraperitoneal closure (SLPEC) of hernia sac high ligation using an ordinary taper needle, and evaluate its safety and efficacy. Methods: From July 2016 to July 2019, 790 children with indirect PIH were treated by laparoscopic surgery. All patients underwent high ligation surgery with a modified single-site laparoscopic technique mainly performed by extracorporeal suturing with an ordinary closed-eye taper needle (1/2 arc 11 × 34). The clinical data were retrospectively analyzed. Results: All surgeries were successful without serious complications. A contralateral patent processus vaginalis (CPPV) was found intraoperatively and subsequently repaired in 190 patients (25.4%). The mean operative time was 15 min (8–25 min) for 557 unilateral hernias and 21 min (14–36 min) for 233 bilateral hernias. The mean postoperative stay was 20 h. Minor complications occurred in five patients (0.63%) and were managed properly, with no major impact on the final outcomes. No recurrence was noted in the patients who were followed up for 6–42 months. No obvious scar was present postoperatively. Conclusion: Modified SLPEC of hernia sac high ligation using an ordinary taper needle for repair of indirect PIH is a safe, reliable, and minimally invasive procedure with satisfactory outcome, with no special device being needed. It is easy to learn and perform and is worthy of popularization in the clinical setting. [ABSTRACT FROM AUTHOR]

We present a study of γ-ray emission from the core-collapse supernova remnant Cas A in the energy range from 0.1 GeV to 10 TeV. We used 65 hr of the Very Energetic Radiation Imaging Telescope Array System (VERITAS) data to cover 200 GeV–10 TeV, and 10.8 yr of Fermi-Large Area Telescope (LAT) data to cover 0.1–500 GeV. The spectral analysis of Fermi-LAT data shows a significant spectral curvature around 1.3 ± 0.4stat GeV that is consistent with the expected spectrum from pion decay. Above this energy, the joint spectrum from Fermi-LAT and VERITAS deviates significantly from a simple power law, and it is best described by a power law with a spectral index of 2.17 ± 0.02stat and a cutoff energy of 2.3 ± 0.5stat TeV. These results, along with radio, X-ray, and γ-ray data, are interpreted in the context of leptonic and hadronic models. Assuming a one-zone model, we exclude a purely leptonic scenario and conclude that proton acceleration up to at least 6 TeV is required to explain the observed γ-ray spectrum. From modeling of the entire multiwavelength spectrum, a minimum magnetic field inside the remnant of Bmin ≈ 150 μG is deduced. [ABSTRACT FROM AUTHOR]

Hot Universe Baryon Surveyor (HUBS) is proposed in China as a major X-ray mission for the next decade. It is designed to be highly focused scientifically, with two primary objectives: (1) detecting X-ray emission from hot baryons in intergalactic medium and circumgalactic medium (CGM), and characterizing their physical and chemical properties; (2) studying, based on the observations, the accretion and feedback processes that are thought to be highly relevant to the heating and chemical enrichment of the baryons in the CGM. Because of very low densities, the signal is expected to be very weak and thus technically difficult to detect. On the other hand, the spectrum of the emission is expected to be line rich, so it would be effective for detecting the hot baryons in bright emission lines. For that, an instrument with high spectral resolution, large effective area and large field of view (FoV) would be required. HUBS will couple a TES-based X-ray imaging spectrometer to a large FoV X-ray telescope to satisfy these requirements. A preliminary design of HUBS is presented. [ABSTRACT FROM AUTHOR]

Galaxy cluster outskirts mark the transition region from the mildly non-linear cosmic web to the highly non-linear, virialized, cluster interior. It is in this transition region that the intracluster medium (ICM) begins to influence the properties of accreting galaxies and groups, as ram pressure impacts a galaxy's cold gas content and subsequent star formation rate. Conversely, the thermodynamical properties of the ICM in this transition region should also feel the influence of accreting substructure (i.e. galaxies and groups), whose passage can drive shocks. In this paper, we use a suite of cosmological hydrodynamical zoom simulations of a single galaxy cluster, drawn from the nIFTy comparison project, to study how the dynamics of substructure accreted from the cosmic web influence the thermodynamical properties of the ICM in the cluster's outskirts. We demonstrate how features evident in radial profiles of the ICM (e.g. gas density and temperature) can be linked to strong shocks, transient and short-lived in nature, driven by the passage of substructure. The range of astrophysical codes and galaxy formation models in our comparison are broadly consistent in their predictions (e.g. agreeing when and where shocks occur, but differing in how strong shocks will be); this is as we would expect of a process driven by large-scale gravitational dynamics and strong, inefficiently radiating, shocks. This suggests that mapping such shock structures in the ICM in a cluster's outskirts (via e.g. radio synchrotron emission) could provide a complementary measure of its recent merger and accretion history. [ABSTRACT FROM AUTHOR]

We present a study of timing properties of the accreting pulsar 2S 1417−624 observed during its 2018 outburst, based on Swift /BAT, Fermi /GBM, Insight-HXMT , and NICER observations. We report a dramatic change of the pulse profiles with luminosity. The morphology of the profile in the range 0.2–10.0 keV switches from double to triple peaks at ∼2.5 |$\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$| and from triple to quadruple peaks at ∼7 |$\rm \times 10^{37}{\it D}_{10}^2\ erg\ s^{-1}$|⁠. The profile at high energies (25–100 keV) shows significant evolutions as well. We explain this phenomenon according to existing theoretical models. We argue that the first change is related to the transition from the sub to the supercritical accretion regime, while the second to the transition of the accretion disc from the gas-dominated to the radiation pressure-dominated state. Considering the spin-up as well due to the accretion torque, this interpretation allows to estimate the magnetic field self-consistently at ∼7 × 1012 G. [ABSTRACT FROM AUTHOR]

Summary: Currents play critical roles in neurons. Direct observation of current flows in cells at nanometre dimensions and picoampere current resolution is still a daunting task. In this study, we investigated the current flows in hippocampal neurons, PC12 cells and astrocytes in response to voltages applied to the cell membranes using conductive atomic force microscopy (CAFM). The spines in the hippocampal neurons play crucial roles in nerve signal transfer. When the applied voltage was greater than 7.2 V, PC12 cells even show metallic nanowire‐like characteristics. Both the cell body and glial filaments of astrocytes yielded CAFM test results that reflect different electrical conductance. To our best knowledge, the electrical characteristics and current transport through components of cells (especially neurons) in response to an applied external voltage have been revealed for the first time at nanometre dimensions and picoampere current levels. We believe that such studies will pave new ways to study and model the electrical characteristics and physiological behaviours in cells and other biological samples. [ABSTRACT FROM AUTHOR]

Aims: Porcine circovirus type 2 (PCV2) can cause postweaning, multisystemic wasting syndrome in pigs, which leads to enormous losses in the swine industry worldwide. Here, a genetically engineered Lactococcus strain expressing the main protective antigen of PCV2, the Cap protein, was developed to act against PCV2 infection as an oral vaccine. Methods and Results: Expression of the Cap protein was confirmed via western blot, ELISA and fluorescence microscopy. Over 90% of the recombinant pAMJ399‐Cap/MG1363 survived a simulated gastrointestinal transit. It also survived the murine intestinal tract for at least 11 days. Then, the safety and immunogenicity of pAMJ399‐Cap/MG1363 in orally immunized mice was evaluated. The levels of the sIgA, IgG and cytokines (IL‐4 and IFN‐γ) obtained from the mice immunized with pAMJ399‐Cap/MG1363 were significantly higher than those in the control groups. Conclusions: pAMJ399‐Cap/MG1363 can survive in the gastrointestinal transit and effectively induce mucosal, cellular and humoral immune response against PCV2 infection via oral administration. Significance and Impact of the Study: This study demonstrates the potential of the genetically engineered Lactococcus lactis as a candidate for an oral vaccine against PCV2. [ABSTRACT FROM AUTHOR]