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On abnormal behaviors of ion beam extracted from electron cyclotron resonance ion thruster driven by rod antenna in cross magnetic field

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Plasma Science and Technology 2021年第8期23卷 150-160页

作者： Juan LI Shenghui fu Yurou YANG Zhenfeng ding School of Physics Dalian University of TechnologyDalian 116024People's Republic of China

In a 2.45 GHz electron cyclotron resonance(ECR)ion thruster powered with rod antenna under a cross magnetic field,abnormal behaviours such as sudden drop of ion beam current(Ib)and larger increasing-rate of Ibin the high microwave power(Pw)discharges at high gas flow rates were observed.A differential method was proposed to reveal the changes in the radial profiles of gray values extracted from the end-view discharge *** increasing-rate of Ibwith respect to Pwwas used to evaluate efficiencies of ion production and *** indicate that discharges are dominantly sustained by ordinary wave via electron heating in the electron plasma resonance layer that can shift along the rod-antenna,and extraordinary wave can only ignite a discharge in the ECR layer in the low gas flow rate *** terms of the confinement region defined by the magnetic field lines intercepting with the screen grid,the confinement region of the optimized 2.45 GHz cross magnetic field takes the shape of hourglass,enabling the high increasing-rate of Ib with respect to Pw in high power discharges at high gas flow *** with the accompanied bright boundary layer appearing in the differentiated image,the sudden drop of Ib in the low gas flow rate regime is attributed to the discharge ignited by the enhanced extraordinary wave in the ECR layer neighbouring the narrowest confinement region,where the produced ions can promptly enter the loss region.

关键词： ECR ion thruster ion beam current discharge mode transition

Target Deployment and Retrieval Using JIAOLONG Manned Submersible in the Depth of 6600 m in Mariana Trench

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China Ocean Engineering 2017年第5期31卷 618-623页

作者： GAO Xiang ding Kang REN Yu-gang fu Wen-tao ding Zhong-jun ZHAO Sheng-ya LIU Bao-hua National Deep Sea Center Institute of Deep-Sea Science and Engineering Chinese Academy of Sciences

China＇s 7000 m manned submersible JIAOLONG carried out an exploration cruise at the Mariana Trench from June to July 2016. The submersible completed nine manned dives on the north and south area of the Mariana Trench from the depth of 5500 to 6700 m, to investigate the geological, biological and chemical characteristics in the hadal area. During the cruise, JIAOLONG deployed a gas-tight serial sampler to collect the water near the sea bottom regularly. Five days later, the sub located the sampler in another dive and retrieved it successfully from the same location, which is the first time that scientists and engineers finished the high accuracy in-situ deployment and retrieval using a manned submersible with Ultra-Short Base Line （USBL） positioning system at the depth more than 6600 m. In this task, we used not only the USBL system of the manned submersible but also a compound strategy, including five position marks, the sea floor terrain, the depth contour, and the heading of the sub. This paper introduces the compound strategy of the target deployment and retrieval with the practical diving experience of JIAOLONG, and provides a promising technique for other underwater vehicles such as manned submersible or Remote Operated Vehicle （ROV） under similar conditions.

关键词： target deployment and retrieval manned submersible USBL Mariana Trench

Effects of heat treatment on properties of multi-element low alloy wear-resistant steel

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China Foundry 2007年第1期4卷 18-21页

作者： SONG Xu-ding fu Han-guang School of Mechanical Engineering Chang ＇an University Xi ＇an 710064 China School of Material Engineering Xi＇an jiaotong University Xi＇an 710000 China

The paper has studied the mechanical properties and heat treatment effects on multi-element low alloy wear-resistant steel (MLAWS) used as a material for the liner of rolling mill torii. The results show that when quenched at 900-920℃ and tempered at 350-370℃, the MLAWS has achieved hardness above 60 HRC, tensile strength greater than 1 600 MPa, impact toughness higher than 18J/cm2 and fracture toughness greater than 37 MPa·m1/2. When the quenching temperature is lower than 900℃, the hardness of the MLAWS increases with the temperature. When the quenching temperature is higher than 900℃, the hardness decreases with the increase of temperature. At a quenching temperature below 920℃, the effect of quenching temperature on the impact toughness is not obvious. In quenching at above 920℃, impact toughness decreases as the temperature increases. When the tempering temperature is exceeding 450℃, the hardness begins to decrease significantly. Tempering at 350℃ has produced the best wear resistance on the MLAWS.

关键词： rolling mill torii liner heat treatment mechanical properties wear resistance

Nutrition-Associated Processes Govern fungal Pathogenicity

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Infectious Microbes & Diseases 2021年第2期3卷 69-78页

作者： Xindi Gao Yi fu Chen ding College of Life and Heath Sciences Northeastern UniversityShenyangLiaoningChina

fungal pathogens present a major common threat across human communities:they cause disease and death in humans,animals,and global food *** development of anti-fungal therapies is hampered primarily by the lack of knowledge about the molecular mechanisms of fungal pathogenicity at the host-pathogen *** studies have shown that nutrition-associated processes such as autophagy and metal homeostasis play essential roles in fungal virulence during systemic *** infection,the host immune system often employs nutrition restriction mechanisms to limit microbial proliferation and facilitate the killing and elimination of invading ***,fast sensing and adaptation to the levels of environmental nutrients are critical if the fungal pathogen is to survive,replicate,and colonize in the *** cells have evolved numerous precise mechanisms to respond to various levels of nutrient *** show that fungal cells manipulate the expression of genes involved in nutrient acquisition,autophagosome formation,toxic nutrient detoxification,or cell morphological transition to counter the anti-fungal strategies of the *** review of the most recent studies of nutrition-related pathways focuses primarily on autophagy,metal homeostasis,and the nutrition-driven morphological switches found in two major human fungal pathogens,Cryptococcus neoformans and Candida *** is a systematic comparison of the functional divergence of nutrition-related genes in the fungal pathogenicity of these evolutionarily distinct but related fungal species.

关键词： nutrition fungal pathogens autophagy Candida albicans Cryptococcus

Biofeedback therapy combined with Baduanjin on quality of life and gastrointestinal hormone level in patients with colorectal cancer

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World Journal of Gastrointestinal Oncology 2022年第6期14卷 1187-1198页

作者： Xiao-ding Zhou Hong-Gang Wei fu-Lu Ai Graduate Work Department Shenyang Sport UniversityShenyang 110102Liaoning ProvinceChina Wushu and Dance Academy Shenyang Sport UniversityShenyang 110115Liaoning ProvinceChina Department of General Surgery Liaoning Tumor HospitalShenyang 110042Liaoning ProvinceChina

BACKGROUND With the change in people’s lifestyles,the incidence of colorectal cancer(CRC)is *** is essential to study the efficacy of various treatment methods for CRC patients to prevent and treat *** To investigate the efficacy of biofeedback therapy combined with Baduanjin in improving the quality of life and gastrointestinal hormone levels of patients with *** A total of 120 patients with CRC who were admitted to our hospital from June 2020 to June 2021 were included in the *** were randomly divided into four groups(n=30):the control group(group A),the biofeedback therapy intervention group(group B),the Baduanjin exercise intervention group(group C),and the combination group(group D).Patients in group A adopted the standard nursing mode and necessary health *** in group B were treated with biofeedback therapy based on routine nursing *** in group C were given Baduanjin intervention for 12 wk based on conventional drug treatment and *** in group D were treated with biofeedback therapy and Baduanjin *** this study,patients’quality of life,gastrointestinal hormone levels,and clinical efficacy in the four groups were observed at baseline and 12 wk after ***,the correlation between gastrointestinal hormone levels and various functional areas of quality of life was *** comparing the observed indicators of patients in the four groups,the efficacy of biofeedback therapy combined with Baduanjin in improving the quality of life and gastrointestinal hormone levels of patients with CRC was *** At baseline,there were no significant differences in quality of life,gastrointestinal hormone levels,or clinical efficacy among the four groups(P>0.05).Twelve weeks after the intervention,the combination group’s quality of life,gastrointestinal hormone levels,and clinical effectiveness were better than those of the three other *** On the basis of routine nursin

关键词： Biofeedback therapy Baduanjin Colorectal cancer Quality of life Gastrointestinal hormone level Clinical efficacy

factors influencing the purification efficiency of photosynthetic bacteria

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Chinese Science Bulletin 2000年第S1期45卷 105-109页

作者： CHEN fanzhong ding Aizhong fu Jiamo SHENG Guoying State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

One strain of photosynthetic bacteria (PSB) was isolated from substrate sludge of fresh-water fishpond. Influence of the use level of PSB culture solution, illumination condition, temperature, salinity, the use level of copper sulfate and dipterex on the purification efficiency was investigated. The results showed that the optimum use level of PSB culture solution was 10 mg/L, and the purification efficiency at illumination was higher than that at black, and if the temperature was lower than 15@, or the use level of sodium chloride, copper sulfate and dipterex were higher than 10 000 mg/L, 0.4 mg/L and 2.0 mg/L, respectively, the purification efficiency dropped distinctly.

关键词： photosynthetic bacteria (PSB) water purification influencing factor.

Immunotherapy in liver transplantation for hepatocellular carcinoma:Pros and cons

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World Journal of Gastrointestinal Oncology 2022年第1期14卷 163-180页

作者： Yi Luo Fei Teng Hong fu Guo-Shan ding Department of Liver Surgery and Organ Transplantation Changzheng HospitalNaval Medical UniversityShanghai 200003China

Liver transplantation(LT)has emerged as a curative strategy for hepatocellular carcinoma(HCC),but contributes to a higher predisposition to HCC recurrence in the immunosuppression context,especially for tumors beyond the Milan *** immunotherapy has dramatically improved survival for immunocompetent patients and has become the standard of care for a variety of tumors,including HCC,it is mainly used outside the scope of organ transplantation owing to potentially fatal allograft ***,accumulative evidence has expanded the therapeutic paradigms of immunotherapy for HCC,from downstaging or bridging management in the pretransplant setting to the salvage or adjuvant strategy in the posttransplant ***,immunotherapy mainly includes immune checkpoint inhibitors(ICIs),adoptive cell transfer(ACT)and vaccine ***,followed by ACT,have been most investigated in LT,with some promising *** of the complex tumor microenvironment and immunoreactivity when immunosuppressants are combined with immunotherapy,it is difficult to reach formulations for immunosuppressant adjustment and the optimal selection of immunotherapy as well as *** addition,the absence of effective biomarkers for identifying rejection and tumor response is still an unresolved barrier to successful clinical immunotherapy applications for *** this review,we comprehensively summarize the available evidence of immunotherapy used in LT that is specific to ***,we discuss clinically concerning issues regarding the concurrent goals of graft protection and antitumor response.

关键词： Hepatocellular carcinoma Liver transplantation Immunotherapy Immune checkpoint inhibitors Adoptive cell transfer Immunosuppressant

Risk analysis of slope instability of levees under river sand mining conditions

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Water Science and Engineering 2012年第3期5卷 340-349页

作者： Zhuo-fu WANG Ji-yong ding Gao-sheng YANG Institute of Engineering Management Hohai University Nanjing 211100 P. R. China

Levees are affected by over-exploitation of river sand and river adjustments after the formation of sand pits. The slope stability is seriously threatened, drawing wide concern among experts and scholars in the area of water conservancy. This study analyzed the uncertainties of slope stability of levees under river sand mining conditions, including uncertainty caused by interest- driven over-exploitation by sand mining contractors, and uncertainty of the distance from the slope or sand pit to the bottom of the levee under the action of cross-flow force after the sand pit forms. Based on the results of uncertainty analysis, the distribution and related parameters of these uncertainties were estimated according to the Yangtze River sand mining practice. A risk model of the slope instability of a levee under river sand mining conditions was built, and the possibility of slope instability under different slope gradients in a certain reach of the Yangtze River was calculated with the Monte Carlo method and probability combination method. The results indicated that the probability of instability risk rose from 2.38% to 4.74% as the pits came into being.

关键词： sand mining," levee risk analysis," slope instability," Monte Carlo method," probabilitycombination method

Enhancement of MAD/MIR phasing at low resolution and a new procedure for automatic phase extension

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Chinese Physics B 2019年第7期28卷 389-395页

作者： Pu Han Yuan-Xin Gu Wei ding Hai-fu fan Key Laboratory of Soft Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physics Science University of Chinese Academy of Sciences Beijing 100049 China

To achieve de novo protein structure determination of challenging cases, multi-wavelength anomalous diffraction(MAD) and multiple isomorphous replacement(MIR) phasing can be powerful tools to obtain low-resolution initial phases from heavy-atom derivative datasets, then phase extension is needed against high-resolution data to obtain accurate *** this context, we propose a direct-methods procedure here that could improve the initial low-resolution MAD/MIR phase *** accordingly, an automated process for extending initial phases to high resolution is also *** two procedures are both implanted in the newly released IPCAS *** cases are used to perform the test, including one set of 4.17 ? MAD data from a membrane protein and two sets of MAD/MIR data with derivatives truncated down to 6.80 ? and 6.90 ?, *** the results have shown that the initial phases generated from the direct-methods procedure are better than that from the conventional MAD/MIR *** automated phase extensions for the latter two cases starting from 6.80 ? to 3.00 ? and 6.90 ? to 2.80 ? are proved to be successful, leading to complete *** may provide convenient and reliable tools for phase improvement and phase extension in difficult low-resolution tasks.

关键词： direct methods multi-wavelength anomalous diffraction(MAD)/multiple isomorphous replacement(MIR) phasing phase extension low-resolution