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Uniaxial and isothermal compression tests of kaolinite were carried out using molecular dynamics simulations. Five different temperatures (300, 400, 500, 600 and 700 K) and pressures ranging from 0.0001 to 50 GPa were selected to study the temperature and pressure effects on the mechanical properties of kaolinite. As kaolinite may undergo a phase transition at ~1572 K, a highest temperature of 700 K was chosen to avoid such structural change. The Young's modulus, strength and elastic constants of kaolinite under various temperatures were calculated, and the relative change of the elastic constant C33 with temperature was found to be almost 12 times greater than the relative change of the interlayer constant C11. The microstructures under various compressive strains were tracked and they exhibited various failure modes in three directions. The temperature and pressure effects on the mechanical properties of three crystal directions were analysed. The results showed that the Young's modulus of the z-direction is the most affected by temperature; however, the influence of temperature on the strengths of the three crystal directions was the same. In addition, the structure of the z-direction was the most sensitive to temperature under the same hydrostatic pressure due to the weak interactions between layers.

High time resolution and accuracy are of critical importance in the studies of timing analysis and time delay localization of gamma-ray bursts (GRBs), soft gamma-ray repeaters (SGRs) and pulsars. The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) consisting of two micro-satellites, GECAM-A and GECAM-B, launched on 2020 December 10, is aimed at monitoring and locating X-ray and GRBs all over the sky. To achieve its scientific goals, GECAM is designed to have the highest time resolution (0.1 $\mu {\rm s}$) among all GRB detectors ever flown. Here, we make a comprehensive time calibration campaign including both on-ground and on-orbit tests to derive not only the relative time accuracy of GECAM satellites and detectors, but also the absolute time accuracy of GECAM-B. Using the on-ground calibration with a $\rm ^{22}Na$ radioactive source, we find that the relative time accuracy between GECAM-A and GECAM-B is about 0.15 $\mu {\rm s}$ (1σ). To measure the relative time accuracy between all detectors of a single GECAM satellite, cosmic-ray events detected on orbit are utilized since they could produce many secondary particles simultaneously record by multiple detectors. We find that the relative time accuracy among all detectors onboard GECAM-B is about 0.12 $\mu {\rm s}$ (1σ). Finally, we use the novel Li-CCF method to perform the absolute time calibration with Crab pulsar and SGR J1935+2154, both of which were jointly observed by GECAM-B and Fermi/GBM, and obtain that the time difference between GECAM-B and Fermi/GBM is 3.06 ± 6.04 $\mu {\rm s}$ (1σ).

In recent years, researchers, pharmaceutical companies, and political makers gradually using more real-world data (RWD) to produce real-world evidence (RWE) for policy-making. A research team of Harvard University launched the RCT DUPLICATE project in 2018, aiming to replicate 30 randomized controlled trials using the medical claims database in order to explore methods for quantifying the efficacy-effectiveness gap and explain its potential sources, to enhance the credibility of the RWE. This paper reviews the background of RCT DUPLICATE Initiative, highlights the research purposes, research design and implementation process of the RCT DUPLICATE Initiative, to help domestic scholars better understand the scope and application value of RWE.近些年，医疗产品监管机构开始重新审视真实世界证据（RWE）对监管决策的潜在价值。RWE能否代替金标准随机对照试验（RCT）产生的证据尚不确定。哈佛大学研究团队于2018年发起了RCT DUPLICATE项目，旨在利用医疗索赔数据库模拟30个RCT，以探索效力-效果差距的量化方法并解释其潜在来源，增强RWE的可信度。本文回顾了RCT DUPLICATE项目的产生背景，重点介绍RCT DUPLICATE项目的研究目的、研究设计和实施流程，以期帮助国内学者更好地理解RWE的适用范围和应用价值。.

With the promotion and application of big medical data, non-interventional real-world evidence (RWE) has been used by regulators to assess the effectiveness of medical products. This paper briefly introduces the latest progress and research results of the RCT DUPLICATE Initiative launched by the research team of Harvard University in 2018 and summarizes relevant research experience based on the characteristics of China's medical service to provide inspiration and reference for domestic scholars to conduct related RWE research in the future.随着医疗大数据的推广与应用，监管机构开始使用非随机化的真实世界证据（RWE）来评估医疗产品的有效性。本文简要介绍了哈佛大学研究团队于2018年发起RCT DUPLICATE项目的最新进展与研究成果，并结合我国医疗服务特点总结了相关研究经验，为国内学者今后开展相关RWE研究提供借鉴。.

This study evaluated the effects of foliar spraying melatonin (MT) on the growth of salt-stressed rice. Seedlings were treated with 50 and 100 mM of NaCl and different concentrations of MT (25, 50, 100, 200, 300, and 400 μM) for 14 days. Different concentrations of MT could promote plant growth significantly under salt stress, particularly at concentrations of 200, 300, and 400 μM. A concentration of 200 μM MT was considered as optimal and used in a subsequent experiment on biomass, water content, antioxidation, mineral nutrition, salt absorption, and distribution of salt-stressed rice seedlings. Results showed that MT’s promoting effect on plant growth under salt stress was evident with time, particularly under high salt stress. MT improved the activities of antioxidant enzymes, reduced membrane lipid peroxidation, alleviated cell injury in plant leaves, and increased N content and Si accumulation in the leaves and roots under salt stress, particularly under high salinity. This compound also inhibited Na uptake and upward transport, but it promoted or maintained the uptake and upward transport of K and Ca in salt-stressed rice. Thus, MT improved the ion homeostasis of K/Na and Ca/Na in plants, particularly in the leaves. Foliar spraying of MT alleviated salt stress on rice by promoting nutrient accumulation or translocation, improving ion homeostasis, which is evident in the leaves, and consequently enhancing its salt resistance. The antioxidative improvement caused by MT might also be related to the improved ion homeostasis.

We propose an iterative method for solving the following iterative functional-differential equation: x ′′ (t) = ⋋1x(t) + ⋋2x[2](t) + … + ⋋nx[n](t) + f(t).

Trans-territory perforator flaps are commonly used to reconstruct large defects of the soft tissues. The distal portion of the flap often becomes necrotic, however, as a result of the jeopardised vasculature of choke zone II. The trophic and vascular regenerative properties of bone marrow mesenchymal stem cells (BMSC) seemed to be a promising approach to prevent flaps becoming ischaemic. The purpose of our study is to evaluate the effects of BMSC on the survival of the three-territory perforator flap. The flap model was created based on the deep circumflex iliac vessel in rats. Eighteen rats were distributed, at random, into three groups. Immediately after the flaps were placed, groups were respectively given a single panniculus carnosus injection at choke zone II of either 1×105 (BMSCslow), 1×106 (BMSCshig) BMSC, or phosphate-buffered saline (PBS). On postoperative day seven, we assessed the gross view of the flap and survival. We also evaluated microvessels by histological examination and angiogenesis-related gene expression by quantitative real-time polymerase chain reaction. After high dosage of BMSC, the flap survival rate, diameter and density of microvessels, vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) levels were significantly higher in the BMSC treatment group than the control group. We therefore confirmed the positive effects of BMSC on the survival of multi-territory perforator flaps.

迷离瘤是胚胎发育时期在非正常部位生长的正常组织，主要根据病理学检查明确诊断，本文报道1例源自左侧咽鼓管、生长至鼻咽部的迷离瘤病例。患儿，男，6月龄，因呼吸困难收入院，全身麻醉下内镜手术切除左侧咽鼓管及鼻咽部肿物，术后病理确诊为迷离瘤。随访2年，未见复发。.

The 12C+12C fusion reaction was studied in the range of E c.m.=8.9 to 21 MeV using the active-target Time Projection Chamber. With full information on all tracks of the reaction products, cross sections of the 12C(12C,8Be)16Og.s. channel and the 12C(12C,3α)12C channel could be measured down to the level of a few milibarns. The 12C(12C,8Be)16Og.s. reaction channel was determined to be 10 mb at E c.m.=11.1 MeV, supporting the direct α transfer reaction mechanism. The 12C(12C,3α)12C reaction channel was studied for the first time using an exclusive measurement. Our result does not confirm the anomaly behavior reported in the previous inclusive measurement by Kolata et al. [Phys. Rev. C 21, 579 (1980)]. Our comparisons with statistical model calculations suggest that the 3α channel is dominated by the fusion evaporation process at E c.m. > 19 MeV. The additional contribution of the 3α channel increases the fusion reaction cross section by 10% at energies above 20 MeV. We also find that an additional reaction mechanism is needed to explain the measured cross section at E c.m. < 15 MeV at which point the statistical model prediction vanishes.

To explore the mechanism of the intestinal barrier damage caused byThirty SD rats were randomly divided into the control group, and the 1-, 3-, 6- and 9-week-infection groups, of 6 rats in each group. Rats in each infection group were orally infected withThe median urinary lactolose to mannitol ratios were 0.29, 0.72, 0.44, 0.46 and 0.38 in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (

本文就新型冠状病毒肺炎疫情期间，如何实施神经介入手术，在手术过程中如何保护医护人员，救治后的患者如何管理等问题，进行探讨及分析，并提出一些建议，望能给同道在疫情常态化后有所指导。.

In order to diagnose the electron cyclotron resonance (ECR) plasma, a high-efficiency collimation system has been developed at the Institute of Modern Physics, and the bremsstrahlung spectra in the range of 10 keV-300 keV were measured on a third generation superconducting ECR ion source, SECRAL-II, with a CdTe detector. Used as a comparative index of the mean energy of the high energy electron population, the spectral temperature, Ts, is derived through a linear fitting of the spectra in a semi-logarithmic representation. The influences of some main source parameters, such as the neutral gas pressure, extraction voltage, microwave power, and bias disk voltage, on the high energy electrons are systemically investigated.

The scar contracture of Achilles tendon in burn patients after operation is easy to cause " foot drop" , which leads to ankle dorsiflexion dysfunction. To solve this problem, the authors designed and made a static progressive ankle foot orthosis. The foot support part and the crus support part of the orthotic device are connected by rivets, and the distal end of the foot support part and the proximal end of the crus support part are pulled by the traction belt on both sides, gradually improving the ankle dorsiflexion function. This static progressive ankle foot orthosis is simple, practical, cost-effective, and worthy of clinical promotion.烧伤患者术后跟腱部位的瘢痕挛缩极易形成足下垂，导致踝关节背屈功能障碍。针对此问题，笔者自行设计、制作了一款静态进展性踝足矫形器。该矫形器足底支撑部分与小腿支撑部分由铆钉连接，两侧的牵拉带牵拉足底支撑部分远心端与小腿支撑部分近心端，从而循序渐进地改善踝关节背屈功能。此静态进展性踝足矫形器制作简单、实用性强、经济有效，值得临床推广。.

To research the long-term corrosion of 16MnR steel radioactive waste container in backfill materials that are lightweight aggregate concrete (LWAC) and Keerjian bentonite, accelerated corrosion test in the backfill environment was studied. The corrosive products during accelerated tests were compared to the ones during simulated tests through morphology observation, component analysis by XRD and grey correlation quantitative evaluation. An approach of the accelerated corrosion test combining enhancing medium with dry-wet alternation was designed. In either LWAC and bentonite enviroment, the corrosion rates of accelerated test and simulated test are quite different, but their corrosion products, corrosion laws and corrosion development trend are similar. For the zinc coating, the correlation coefficients of the accelerated test in LWAC and bentonite was 0.672 and 0.734, respectively. Moreover, the accelerated speedup of the designed accelerated corrosion test is greater than 337. Therefore, the des...

Natural factors and non-pharmaceutical interventions (NPIs) have effect on COVID-19 transmission, but it’s difficult to separate these two factors. The Compound natural factor (CNF) model is propos...

This paper presents a numerical investigation into the vulnerability to liquefaction of an embedded pipeline exposed to ocean storms. In this study a series of irregular waves similar to a real ocean storm were generated using the JONSWAP spectrum, and their motions with the presence of ocean currents are described using the Reynolds-Averaged Navier–Stokes (RANS) equations. Under storm waves and currents, the dynamics of a seabed with an embedded pipeline were reproduced using a coupled fluid-dynamic framework. An advanced constitutive model (modified Pastor-Zienkiewicz Mark-III) was used to describe the cyclic plasticity of soil. This model was calibrated according to the given soil properties; the predicted results match the wave flume test and geotechnical centrifugal test fairly well when the evolution of residual pore water pressure near the pipe and/or further away are considered. The numerical results indicated that seabed soil is more susceptible to liquefaction due to regular waves than irregular waves. The specific gravity of the pipe can significantly affect the onset and spread of liquefaction in the neighbouring region. As a practical guide, a relationship between the critical wave height and the depth to which the pipe is buried is proposed to control the liquefaction at the bottom of the pipe by selecting feasible backfill materials based on operational requirements and ocean storm conditions.

The drainage consolidation method has been efficiently used to deal with soft ground improvement. Nowadays, it has been suggested to use a new sand soil which is a composite of sand and recycled glass waste. The permeability performance of glass-sand soil was explored to judge the feasibility of glass-sand soil backfilled in the drainage consolidation of sand-drained ground. For comparison purposes, different mix proportions of recycled glass waste, fineness modulus, and glass particle size were analyzed to certify the impact on the permeability coefficient and the degree of consolidation. The numerical results show that adding a proper amount of recycled glass waste could promote the permeability performance of glass-sand soil, and the glasssand soil drain could be consolidated more quickly than a sand drain. Experiments showed that glass-sand soil with the a 20% mix of recycled glass waste reveals the optimum performance of permeability.