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In this article, we demonstrate the dependence of the adhesive force (

High-entropy alloys (HEAs) are promising to provide effective antiballistic capability because of their superior mechanical properties. However, the twinning-active Cantor alloy is found less ballistic resistant, compared with its Mn-free companion. It is unclear how the HEAs resist ballistic impact and why Mn does not benefit the ballistic resistance. Here, we used molecular dynamics simulations to investigate the ballistic resistances of CrMnFeCoNi and CrFeCoNi and elucidate underlying mechanisms. It is shown that the alloys’ ballistic resistances dominantly benefit from active dislocations generated at higher strain rates. Stronger atomic bonding and higher dislocation densities make the CrFeCoNi easier to be strain hardened with elevated toughness to resist high-speed deformation, while weaker atomic bonding and easier occurrence of dislocation tangling make CrMnFeCoNi less resistant to failure under ballistic impact. This work helps better understand the antiballistic behavior of HEAs and guide the design of armor and energy-absorption materials.

To set the cultivation goal with adaptation to rural order-oriented medical students, the teaching mode of

Background/Aims The pathophysiology of jackhammer esophagus (JE) remains unknown but may be related to gastroesophageal reflux disease or medication use. We aim to determine if pathologic acid exposure or the use of specific classes of medications (based on the mechanism of action) is associated with JE. Methods High-resolution manometry (HRM) studies from November 2013 to March 2019 with a diagnosis of JE were identified and compared to symptomatic control patients with normal HRM. Esophageal acid exposure and medication use were compared between groups. Multivariate regression analysis was performed to look for predictors of mean distal contractile integral. Results Forty-two JE and 127 control patients were included in the study. Twenty-two (52%) JE and 82 (65%) control patients underwent both HRM and ambulatory pH monitoring. Two (9%) JE patients and 14 (17%) of controls had evidence of abnormal acid exposure (DeMeester score > 14.7); this difference was not significant (P = 0.290). Thirty-six (86%) JE and 127 (100%) control patients had complete medication lists. Significantly more JE patients were on long-acting beta agonists (LABA) (JE = 5, control = 4; P = 0.026) and calcium channel blockers (CCB) (JE = 5, control = 3; P = 0.014). Regular opioids (β = 0.298, P = 0.042), CCB (β = 0.308, P = 0.035), and inhaled anticholinergics (β = 0.361, P = 0.049) predicted mean distal contractile integral (R2 = 0.082, F = 4.8; P = 0.003). Conclusions Pathologic acid exposure does not appear to be associated with JE. JE patients had increased CCB and LABA use. The unexpected finding of increased LABA use warrants more investigation and may provide support for a cholinergic etiology of JE. (J Neurogastroenterol Motil 2020;26:224-231)

Previous studies have shown that adding a section of critical density plasma on the front surface of solid target can effectively improve the laser energy absorption efficiency. Here, we have investigated laser–plasma interactions with different scale lengths of plasma in front of the target created by a pre-ablation laser pulse. A variety of experimental diagnostics employed together with particle-in-cell simulations give us deep insight into these processes. We found that the laser-induced electromagnetic pulse (EMP) intensity inside the target chamber and the target normal sheath acceleration sheath field accelerated protons were promoted using pre-plasma. The transient current due to hot electron emissions is considered to be one of the main radiation sources of EMP emissions within our measurement bandwidth. In our experiment, this current was guided to a grounded conductive wire attached to the rear surface of the target and measured by proton dynamic imaging technique. The discharging currents together with the guided fields were enhanced more than twice. The reflection spectra of experiments and simulations are compared, which reveal that the energy absorption efficiency was increased with proper plasma scale length, resulting in all the measured signals promoted.

Doping or partially substituting WC with metals, e.g., Mo and Cr, can lower its density while keeping the strength of the modified carbides similar to that of WC, making them attractive as the reinforcement for hardfacing overlays and tool steels, since they can be distributed homogeneously in the metal matrix. However, it is unclear if the doped WC has desirable interfacial bonding with the matrix, e.g., iron. In this study, we investigated the interfacial bonding of Mo- and Cr-doped WC, compared to that of mono-WC, with austenite and ferrite irons via first-principles calculations. [Formula: see text], [Formula: see text], and [Formula: see text] interfaces for both ferrite and austenite with the lowest interfacial mismatch were investigated. Characteristics of the formed interfacial bonds were studied based on the electron localization function, electronic density of states, bond order, and net charge. It was demonstrated that the Mo and Cr-doped WC carbides, (W4−x, M)C4, show comparable or higher adhesive work with iron, compared to that of mono-WC with iron. The metal-substituted or doped W4C4 carbides are promising replacements of heavier WC for tool steels and ferrous hardfacing overlays.

A beamline is required to focus proton beams produced by laser plasma accelerator to high charge density spots for practical applications. The Compact LAser Plasma Accelerator (CLAPA) coupled with an image-relaying beamline has been built at Peking University. While the collection section of this beamline is an electromagnetic quadrupoles (EMQs) triplet with certain aperture, more than 71 % of the protons are lost in the inlet end face or vacuum tube wall of triplet due to their divergence angles. Here we show the development of a high transmission efficiency and tunable collection system in the beamline by adding two permanent magnet quadrupoles (PMQs) with magnetic field strengths of about 200 and 120 T/m respectively in front of the triplet. As a result, by monitoring the relative position of the PMQs and the currents of the EMQs, the focusing energy is able to be adjusted ranging from 2 to 10 MeV, and the transmission efficiency is 1.4 to 3 times as high as only collected by EMQs triple.

As a novel X-ray focusing technology, lobster eye micro-pore optics (MPO) feature both a wide observing field of view and true imaging capability, promising sky monitoring with significantly improved sensitivity and spatial resolution in soft X-rays. Since first proposed by Angel (1979), the optics have been extensively studied, developed and trialed over the past decades. In this Letter, we report on the first-light results from a flight experiment of the Lobster Eye Imager for Astronomy ($LEIA$), a pathfinder of the wide-field X-ray telescope of the Einstein Probe mission. The piggyback imager, launched in July 2022, has a mostly un-vignetted field of view of $18.6^\circ \times 18.6^\circ $. Its spatial resolution is in the range of 4$-$7 arcmin in FWHM and the focal spot effective area is 2$-$3 cm$^2$, both showing only mild fluctuations across the field of view. We present images of the Galactic center region, Sco X-1 and the diffuse Cygnus Loop nebular taken in snapshot observations over 0.5$-$4 keV. These are truly wide-field X-ray images of celestial bodies observed, for the first time, by a focusing imaging telescope. Initial analyses of the in-flight data show excellent agreement between the observed images and the on-ground calibration and simulations. The instrument and its characterization are briefly described, as well as the flight experiment. The results provide a solid basis for the development of the present and proposed wide-field X-ray missions using lobster eye MPO., Comment: 11 pages, 4 figures. Accepted for publication in Astrophysical Journal Letter

The cytotoxic effect targeting hepatitis B virus (HBV) infected hepatocytes from virus-specific cytotoxic T cells and the neutralizing antibodies secreted by virus-specific B cells play an important role in the immune control and elimination of HBV. In patients with chronic hepatitis B, the liver immune microenvironment usually presents a suppression state, and virus-specific immune cells are mostly exhausted. Studies on the interaction between HBV and host immunity during infection, especially the influence of various viral proteins on immune cell function, will contribute to understanding the mechanism of the chronicity of HBV infection, disease progression, and optimization of immunotherapy against HBV. The review summarized the suppressive effects of HBV viral proteins on the host innate immunity and adaptive immune system, to help us understanding the mechanism(s) relevant to the observation that a CHB patient with HBeAg loss and lower HBsAg level is more likley achieving functionall cure. and expect to provide new sights for accelerate virus clearance and achieve functional cure of chronic hepatitis B, by removing the HBV viral proteins and consequently, liberting host immune from suppression state.乙型肝炎病毒（HBV）特异性细胞毒性T淋巴细胞对感染肝细胞的杀伤以及B淋巴细胞分泌的中和抗体在HBV感染的免疫控制和清除中均起到了重要作用。但在慢性乙型肝炎患者中，肝脏免疫微环境通常处于抑制状态，病毒特异性免疫细胞多为功能耗竭表型。研究HBV慢性感染过程中病毒与宿主免疫的相互作用，有助于加深对HBV感染慢性化及疾病进展机制的理解，同时还可为针对HBV的免疫治疗提供新的思路。现系统总结主要的HBV病毒蛋白对宿主固有免疫及适应性免疫的影响，这在一定程度上解释了HBeAg阴转后，HBsAg低水平的患者更易于获得临床治愈的原因。希望未来能更有效地解除病毒蛋白诱导的宿主免疫抑制，帮助实现慢性乙型肝炎的临床治愈。.

Background Upper esophageal sphincter (UES) function may be evaluated manometrically using a solid-state high-resolution manometry (HRM) system, which allows for the measurement of manometric parameters specific to the UES. While many of these parameters have yet to be validated for use in clinical practice, there is some suggestion that there may be an association between esophageal motility and UES function. Aims We aimed to identify the relationship between UES manometric variables and high-resolution esophageal manometry (HREM) diagnoses. Methods A retrospective analysis of HREM studies was performed between 2019 and 2021. Extraction of esophageal and UES manometric variables were performed. UES manometric values of interest included: mean basal pressure (mmHg), mean residual pressure (mmHg), relaxation time-to-nadir (ms), relaxation duration (ms), and recovery time (ms). Relationships between manometric diagnosis (Chicago Classification version 3) and UES manometric variables were explored. All values are expressed a medians and group means were compared with the non-parametric Mann-Whitney U test. Results 2119 symptomatic patients underwent HREM over the study period. Manometric diagnoses were achalasia (72 patients), esophagogastric junction outflow obstruction (286), absent contractility (108), distal esophageal spasm (53), jackhammer esophagus (32), and ineffective esophageal motility (694). 886 patients had no specific motility disorder; 643 of whom had ≤ 20% ineffective swallows and were considered symptomatic controls. Patients with achalasia had significantly higher mean basal pressures (63.2 vs. 54.4, p = .001), mean residual pressure (3.8 vs. -1.9, p < .001), relaxation-time-to-nadir (182.0 vs. 142.0, p = .005), relaxation duration (820.5 vs. 708.0, p < .001) and recovery time (623.0 vs. 562, p < .001) compared to control patients. Among patients with achalasia, the presence of panesophageal pressurization correlated weakly with recovery time (R2 .3, p = .03). Patients with ineffective esophageal motility had significantly higher mean basal pressures (61.7 vs. 54.0, p < .001). Among all patients, patients with incomplete bolus clearance (≥ 30%) had significantly higher UES mean basal pressure (58.9 vs. 54.6, p = .004), mean residual pressure (-.62 vs. -2, p < .001), relaxation duration (724.0 vs. 707.0, p = .014) and recovery time (580 vs. 558.0, p < .001). Conclusions Patients with achalasia may have higher basal and residual UES pressures, and slower relaxation compared to patients with normal esophageal motility. This may reflect dynamic changes of the UES in response to obstruction at the esophagogastric junction. Elevated UES pressures are also seen in patients with ineffective esophageal motility, potentially reflecting a response to poor bolus clearance. More work needs to be done to validate these parameters in clinical practice. Funding Agencies None

Cracks of sluice hoist beams due to the load and aging of the material threaten the safety of sluice structural system. As the one of the main methods of damage detection, the non-destructive detection method based on natural frequency is still insensitive to local damage. Therefore, this paper proposes a method for hoist beams damage detection driven by resonance frequency band based on local primary frequency in the local mode. Firstly, the possibility of damage detection based on local primary frequency is discussed and the procedure of determining resonance frequency band is explained. Then the damage identification index based on the change ratio of local primary frequency is provided. Finally, numerical results demonstrate the correctness and effectiveness of the proposed method. The proposed method can provide reference for damage detection of hoist beams and health monitoring of sluice structural system.

High pressure side, as the runner outlet at pump mode and runner inlet at turbine mode, playing an important role in controlling hydraulic loss and flow characteristics in vaneless region, affecting both steady characteristics and unsteady characteristics. While when it comes to three-dimensional inverse design of a pump-turbine blade, scholars are forces on the design method in runner flow channel, ignoring the geometry profile of high-pressure side. Hence, in present paper, concepts “swept”, “bowed (lean)” and “twisted” are innovatively introduced, eight new parameters are proposed to control the profile of blade high pressure side. And then a multi-objective optimization design system consisting of geometry generation, computational fluid dynamics, design of experiment, approximation model, multi-objective genetic algorithm, and self-organization map is built. Efficiency at both pump mode and turbine mode and S margin at turbine mode are selected as optimization objectives in the first optimization step. Then, the hump margin is regard as the objective in the second optimization step. Based on the two-step optimization, a runner with optimized high-pressure side is obtained and CFD results show that compared with the original runner, the efficiency at rated points and the margin of unsteady characteristics can be increased. The parametric design method on high-pressure side presented in our paper can be regard as an essential supplement to the traditional design method in hydraulic machinery.

Background There are little data evaluating the performance of the 3-dimensional high-definition anorectal manometry (3D-HDAM) system in the diagnosis of dyssynergic defecation. Physical properties of the thicker, rigid, 3D-HDAM probe may have implications on the measurements of anorectal pressures. Aim Our aim was to compare 3D-HDAM to balloon expulsion test and magnetic resonance (MR) defecography. Methods Consecutive constipated patients referred for anorectal function testing at the Calgary Gut Motility Centre (Calgary, Canada) between 2014 and 2019 were assessed. All patients underwent anorectal manometry with the 3D-HDAM probe, and a subset underwent BET or MR defecography. Anorectal manometric variables were compared between patients who had normal and abnormal BET. Results Over the study period, 81 patients underwent both 3D-HDAM and BET for symptoms of constipation. 52 patients expelled the balloon within 3 minutes. Patients with abnormal BET had significantly lower rectoanal pressure differential (RAPD) (-61 vs. -31 mmHg for normal BET, p = 0.03) and defecation index (0.29 vs. 0.56, p = 0.03). On logistic regression analysis, RAPD (OR: 0.99, 95% CI: 0.97-0.99, p = 0.03) remained a negative predictor of abnormal BET. On ROC analysis, RAPD had an AUC of 0.65. There was good agreement between dyssynergic patterns on 3D-HDAM and defecographic evidence of dyssynergia (sensitivity 80%, specificity 90%, PLR 9, NLR 0.22, accuracy 85%). Conclusions Manometric parameters, when measured with the 3D-HDAM probe, poorly predict prolonged balloon expulsion time. RAPD remains the best predictor of prolonged balloon expulsion time. The 3D-HDAM probe may not be the ideal tool to diagnose functional defecatory disorders.

Simultaneous enhancement of strength and ductility is one of the eternal topics for the community of metallic materials. The heterostructure architecture, e. g. layered structure, is one of the potential methods to evade the strength-ductility trade-off dilemma in recent years. However, there is still a lack of a deeper understanding to excellent strength-ductility combinations. In the present study, we focused on the local stress, which drives local plastic deformation. The local represents the affected scale of the stress. The evolution processes of local stress/strain upon loading of typical model materials of Ti/Ti, Ti/Al, and Al/Al layered metals (LMs) were quantitatively characterized by in situ electron microscope, synchrotron X-ray diffraction, and neutron diffraction. We found that the deformation characteristics were closely associated with the local stress/strain evolution process, and highlighted the key role of local stress/strain in revealing the deformation mechanisms. This work therefore may open a new route to design new metallic materials through the tailoring of local stress/strain evolution.

Matter and radiation at extremes 5(6), 064402 (2020). doi:10.1063/5.0014854, Published by AIP Publishing, Melville, NY

The rapid development of big data analytics technologies and tools, particularly the related distributed computing technologies, which divide large problems into smaller ones, provides important technical support for developing big earth data research. To realize the effective utilization of big data computing resources, it is important to overcome the potential incompatibility and inconsistency among the distributed computing nodes. Using standardized GIS web service interfaces is a promising approach to link existing heterogeneous GIS platforms through standardized protocols and establish a universal, platform-independent computing layer to improve the efficiency of computing resources for big earth data analysis. This research analyzed the requirements of distributed computing, and further proposed a standardized GIS web service-oriented shared-nothing architecture by comparing various mainstream distributed computing architectures and related web service specifications in the industry. For example, the prediction of Lophelia pertusa coral distribution by random forest is the application of the method discussed in this paper.

Mechanical strength and wear resistance of chromium carbides are relatively low compared to other transition metal (TM) carbides, such as TiC or WC. However, carbides can be tailored by partially substituting their host metal elements with other TMs. In this computational study with first-principles calculations, we investigated the effects of TMs on the stability and properties of metastable CrC carbide having a face-centered cubic structure. It is demonstrated that most TMs in IV and V groups can improve the thermodynamic stability of CrC with negative formation energies, meaning that such TM-substituted CrC can be formed using equilibrium or near-equilibrium synthesis routes. Mechanisms for the improved stability and mechanical properties of CrC by TM substitution were investigated through analyzing corresponding changes in the density of states, charge density distribution, and Bader charge. It is shown that the improved stability and properties of TM-substituted CrC result from changes in the distributions of covalent, ionic, and metallic bonds. TM-substituted CrC carbides with different densities provide more alternatives or options for widened applications of the Cr carbide family.