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World Journal of Clinical Cases 2024年第6期12卷 1144-1149页

作者： Xiang-Xiang Wu jian Cui Shi-Yao Wang tian-tian Zhao Ya-Fei Yuan Long Yang Wei Zuo Wen-jian Liao Department of Respiratory and Critical Care The First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina China-Japan Friendship jiangxi Hospital Nanchang 330006Jiangxi ProvinceChina Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship HospitalBeijing 100029China

BACKGROUND This study presents a case of rapidly developing respiratory failure due to antisynthetase syndrome(AS)following coronavirus disease 2019(COVID-19)in a 33-year-old man diagnosed with Klinefelter syndrome(KS).CASE SUMMARY A 33-year-old man with a diagnosis of KS was admitted to the Department of Pulmonary and Critical Care Medicine of a tertiary hospital in China for fever and shortness of breath 2 wk after the onset of *** tomography of both lungs revealed diffuse multiple patchy heightened shadows in both lungs,accompanied by signs of partial bronchial *** next-generation sequencing of the bronchoalveolar lavage fluid suggested absence of pathogen.A biopsy specimen revealed organizing pneumonia with alveolar septal ***,extensive auto-antibody tests showed strong positivity for anti-SSA,anti-SSB,anti-Jo-1,and *** multidisciplinary discussions,the patient received a final diagnosis of AS,leading to rapidly progressing respiratory *** This study underscores the clinical progression of AS-associated interstitial lung disease subsequent to viral infections such as COVID-19 in patients diagnosed with KS.

关键词： Antisynthetase syndrome COVID-19 Klinefelter syndrome Interstitial lung disease Anti-Jo-1 Case report

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矿井数字移动通信新型帧同步保护方案

辽宁工程技术大学学报（自然科学版） 2005年第3期24卷 381-383页

作者：田子建孙继平王继林中国矿业大学(北京校区)信息研究所北京100083 浙江财经学院信息学院杭州310012

介绍了一种在多址方式为TDMA的蜂窝制矿井数字移动通信系统中帧同步的实现,针对井下多径衰落大的特点,提出了一种新型的抗衰落帧同步保护方案。并将该方案与CCITT推荐的帧同步保护方案进行比较,分别阐述两个方案的工作机制并分析它们的... 详细信息

介绍了一种在多址方式为TDMA的蜂窝制矿井数字移动通信系统中帧同步的实现,针对井下多径衰落大的特点,提出了一种新型的抗衰落帧同步保护方案。并将该方案与CCITT推荐的帧同步保护方案进行比较,分别阐述两个方案的工作机制并分析它们的工作特点,理论分析和井下试验都表明CCITT方案在多径衰落较严重的井下难以达到理想的通信效果。在误码率较高的井下环境,抗衰落保护方案的性能优于CCITT方案。

关键词：矿井移动通信 TDMA MSP430 帧同步保护

A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks

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Petroleum Science 2024年第2期21卷 1099-1112页

作者： Wen-Quan Deng tian-Bo Liang Wen-Zhong Wang Hao Liu Jun-Lin Wu Fu-jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water *** the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. Fur

关键词： Imbibition Multiphase flow Tight rock Interacting capillary bundle model Wettability

Impact of body mass index on adverse kidney events in diabetes mellitus patients: A systematic-review and meta-analysis

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World Journal of Clinical Cases 2024年第3期12卷 538-550页

作者： Jing-Fang Wan Yan Chen tian-Hua Yao Ya-Zhou Wu Huan-zi Dai Department of Nephrology Army Medical UniversityChongqing 400042China Department of Nephrology Chongqing Western HospitalChongqing 400052China Health Statistics Army Medical UniversityChongqing 400038China Department of Nephrology Daping HospitalArmy Medical UniversityChongqing 400042China

BACKGROUND The incidence of chronic kidney disease among patients with diabetes mellitus(DM)remains a global ***-term obesity is known to possibly influence the development of type 2 diabetes ***,no previous meta-analysis has assessed the effects of body mass index(BMI)on adverse kidney events in patients with *** To determine the impact of BMI on adverse kidney events in patients with *** A systematic literature search was performed on the PubMed,ISI Web of Science,Scopus,Ovid,Google Scholar,EMBASE,and BMJ *** included trials with the following characteristics:(1)Type of study:Prospective,retrospective,randomized,and non-randomized in design;(2)participants:Restricted to patients with DM aged≥18 years;(3)intervention:No intervention;and(4)kidney adverse events:Onset of diabetic kidney disease[estimated glomerular filtration rate(eGFR)of<60 mL/min/1.73 m2 and/or microalbuminuria value of≥30 mg/g Cr],serum creatinine increase of more than double the baseline or end-stage renal disease(eGFR<15 mL/min/1.73 m2 or dialysis),or *** Overall,11 studies involving 801 patients with DM were *** BMI(≥25 kg/m2)was significantly associated with higher blood pressure(BP)[systolic BP by 0.20,95%confidence interval(CI):0.15–0.25,P<0.00001;diastolic BP by 0.21 mmHg,95%CI:0.04–0.37,P=0.010],serum albumin,triglycerides[standard mean difference(SMD)=0.35,95%CI:0.29–0.41,P<0.00001],low-density lipoprotein(SMD=0.12,95%CI:0.04–0.20,P=0.030),and lower high-density lipoprotein(SMD=–0.36,95%CI:–0.51 to–0.21,P<0.00001)in patients with DM compared with those with low BMIs(<25 kg/m2).Our analysis showed that high BMI was associated with a higher risk ratio of adverse kidney events than low BMI(RR:1.22,95%CI:1.01–1.43,P=0.036).CONCLUSION The present analysis suggested that high BMI was a risk factor for adverse kidney events in patients with DM.

关键词： Obesity Body mass index Diabetes mellitus Adverse kidney events Systematic-review Meta-analysis

Chemical Synthesis of a Key Precursor Relevant to the Tetrasaccharide Repeating Unit from Treponema medium ATCC 700293

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Chinese Journal of Chemistry 2024年第14期42卷 1615-1622页

作者： Wenbin Sun Guangzong tian Meiru Ding Chunjun Qin Xiaopeng Zou Jing Hu jian Yin Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of Biotechnology&School of Life Sciences and Health EngineeringJiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China Wuxi School of Medicine Jiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China

Treponema is a Gram-negative anaerobic bacterium,among which the pathogenic Treponema can cause various diseases,such as venereal syphilis(Treponema pallidum),yaws(Treponema carateum),and oral diseases(Treponema denticola and Treponema medium).Although different from conventional lipopolysaccharides,the extracellular glycoconjugate of Treponema may still be a potential antigen and provide a candidate for vaccine ***,we completed the first chemical synthesis of Treponema medium ATCC 700293 tetrasaccharide precursor containing L-ornithine(L-Orn)and D-aspartic acid(D-Asp)*** efficiency of non-reducing end disaccharide formation has been improved by optimizing the assembly of the protecting groups in the donors and ***[3+1]glycosylation strategy attempted to reduce the length of the acceptor to increase the nucleophilicity of the hydroxyl group,thereby improving the efficiency of synthesizing the target *** L-Orn derivative was introduced at the final stage due to its influence on the glycosylation stereospecificity and ***,the successful introduction of two amino acid derivatives and the synthesis of a tetrasaccharide precursor with complex functional-group modifications have provided valuable insights for synthesizing other complex bacterial glycans.

关键词： Glycosylation Total synthesis Treponema medium ATCC 700293 Tetrasaccharide precursor Protecting group Oligosaccharides Regioselectivity Neighboring-group effects

Synthesis,Structure and Chemical Bonding of Polyantimony Clusters Containing Coinage Metals[M_(2)Sb_(14)]^(4-)(M=Cu,Ag)

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Chinese Journal of Chemistry 2024年第6期42卷 617-622页

作者： Wei-Xing Chen Yu-He Xu Cui-Cui Wang Lei Qiao zi-Yan Guo Wen-Juan tian Zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin300350 China Institute of Molecular Science Shanxi UniversityTaiyuanShanxi030006 China

Binary polyantimony clusters,namely[Cu_(2)Sb_(14)]^(4–) and [Ag_(2)Sb_(14)]^(4–),containing coinage metals,were successfully synthesized and characterized,in which two homoatomic Sb73–subunits are bridged by two coinage metals in η^(4):η^(1) and η^(1):η^(1) coordination modes,***[M_(2)Sb_(14)]^(4-),two bridging Cu ions and two Sb atoms form a planar rhombic unit,which was revealed to have antiaromatic properties by theoretical *** electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M^(+) ions.

关键词： Polyantimony cluster Copper Silver Antiaromaticity Metallophilic interaction Quantum chemical calculations

One-pot and One-step Cu(0)-mediated Reversible-Deactivation Radical Polymerization of N-Isopropylacrylamide(NIPAM) in Water

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Chinese Journal of Polymer Science 2024年第1期42卷 1-6,I0004页

作者： zi-Shan Li Jing Lyu Bei Qiu Ying-Hao Li Ruth Foley Ri-jian Song Melissa Johnson Qiang Geng Wen-Xin Wang Institute of Precision Medicine(AUST-IPM) Anhui University of Science and TechnologyHuainan 232001China Charles Institute of Dermatology School of MedicineUniversity College DublinDublin D04 V1W8Ireland

Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP) of the water-soluble monomer Nisopropylacrylamide(NIPAM) has been challenging with the problems of high dispersity, poor control over the molecular weights(MWs) or complex or multi reaction steps, etc. In this work, we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP. The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RDRPs is to ensure sufficient Cu~I at the very beginning, and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process. For NIPAM, which has a high propagation rate constant, the deactivation control can be effectively enhanced by extra adding deactivator(i.e., Cu~II) to the system. Moreover, a low reaction temperature(4 ℃) is necessary in the controlled synthesis of higher MW poly(Nisopropylacrylamide)(PNIPAM) to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST). Through this new kinetically controlled strategy, PNIPAMs with well-defined structure, narrow molecular weight distributions(MWDs) and varied MWs were successfully achieved.

关键词： Cu(0)-mediated RDRP N-isopropylacrylamide Propagation Deactivation Reaction parameters

Influence of sintering time on microstructure and properties of hot oscillatory pressing sintered W–Cu refractory alloys

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Tungsten 2024年第2期6卷 323-332页

作者： zi-Qian Wu Wei Zhao Ka Gao Shi-Hao Du Qing-Quan Kong De-jian Sun Yang Gao School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou 450015China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of General Medicine Changhai HospitalShanghai 200000China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China Sichuan Province Engineering Technology Research Center of Powder Metallurgy Chengdu UniversityChengdu 610106China

W–Cu refractory alloys are widely used in aerospace,aviation,electronics,power,and other fi ***,because of its large melting point diff erence between alloy elements,the conventional powder metallurgy method required a long time of high temperature sintering is very likely to cause low density and abnormal grain size ***,90W-10Cu refractory alloys were successfully prepared by hot oscillatory pressing(HOP)under diff erent sintering time in this *** the infl uence of sintering time on the microstructure,grain size,density,Vickers hardness,room-tensile property,and electrical conductivity of the W–Cu refractory alloy was systematically *** results showed that during the short sintering time(30–90 min),the density,Vickers hardness,tensile strength,and electrical conductivity of the W–Cu refractory alloy increased signifi cantly to 98.7%,163.29 HV 30,507.3 MPa,and 14.2%International Annealed Copper Standard with the sintering time increasing,respectively,while its grain size showed no obvious *** the sintering time further increased to 120 min,the density was basically consistent with the sintering time of 90 ***,the prolonged high temperature sintering resulted in the grain growth of the samples,which caused the deterioration of the Vickers hardness,room-tensile strength,and conductivity properties of the W–Cu refractory *** the same sintering time,the density,Vickers hardness,and electrical conductivity of the HOP sintered W–Cu refractory alloy were signifi cantly higher than those of the HP sintered *** was indicated that high density,fi ne-grain,and excellent properties W–Cu refractory alloys could be prepared by hot oscillatory pressing under appropriate sintering time.

关键词： W–Cu refractory alloy Hot oscillatory pressing Sintering time Microstructure Property

Analysis of the electron transfer pathway in small laccase by EPR and UV-vis spectroscopy coupled with redox titration

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Magnetic Resonance Letters 2024年第3期4卷 52-59页

作者： Lu Yu Aokun Liu jian Kuang Ruotong Wei Zhiwen Wang Changlin tian High Magnetic Field Laboratory Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei230031China Department of Endocrinology Institute of Endocrine and Metabolic DiseaseThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineHefei National Research Center for Physical Sciences at the MicroscaleJoint Center for Biological Analytical ChemistryAnhui Engineering Laboratory of Peptide DrugAnhui Laboratory of Advanced Photonic Science and TechnologyUniversity of Science and Technology of ChinaHefei230026China

Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer between substrate, copper centers, and O2is one of the key steps in the catalytic turnover of SLAC. However, limited research has been conducted on the electron transfer pathway of SLAC and SLAC-catalyzed reactions, hindering further engineering of SLAC to produce tunable biocatalysts for novel applications. Herein, the combinational use of electron paramagnetic resonance(EPR) and ultraviolet-visible(UV-vis) spectroscopic methods coupled with redox titration were employed to monitor the electron transfer processes and obtain further insights into the electron transfer pathway in SLAC. The reduction potentials for type 1 copper(T1Cu), type 2 copper(T2Cu) and type 3copper(T3Cu) were determined to be 367 ± 2 mV, 378 ± 5 m V and 403 ± 2 mV,respectively. Moreover, the reduction potential of a selected substrate of SLAC, hydroquinone(HQ), was determined to be 288 mV using cyclic voltammetry(CV). In this way, an electron transfer pathway was identified based on the reduction potentials. Specifically,electrons are transferred from HQ to T1Cu, then to T2Cu and T3Cu, and finally to ***, superhyperfine splitting observed via EPR during redox titration indicated a modification in the covalency of T2Cu upon electron uptake, suggesting a conformational alteration in the protein environment surrounding the copper sites, which could potentially influence the reduction potential of the copper sites during catalytic processes. The results presented here not only provide a comprehensive method for analyzing the electron transfer pathway in metalloenzymes through reduction potential measurements, but also offer valuable insights for further engineering and directed evolution studies of SLAC in the aim for biotechnological and industrial applications.

关键词： Electron paramagnetic resonance Redox titration Electron transfer Reduction Potential Small laccase

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基于距离约束的井下目标定位方法

煤炭学报 2014年第4期39卷 789-794页

作者：刘晓阳李宗伟方轲田子建中国矿业大学(北京)机电与信息工程学院北京100083 煤炭科学研究总院安全装备技术研究分院北京100013

煤矿井下巷道为狭长的条状结构,信号衰减较大,地面已有的目标定位方法和技术难以直接应用于井下,现有的矿井目标定位主要采取基于时间和信号强度的测距方法,而这些方法并没有考虑到井下巷道的条状结构特点,定位误差较大,依据矿井巷道的... 详细信息

煤矿井下巷道为狭长的条状结构,信号衰减较大,地面已有的目标定位方法和技术难以直接应用于井下,现有的矿井目标定位主要采取基于时间和信号强度的测距方法,而这些方法并没有考虑到井下巷道的条状结构特点,定位误差较大,依据矿井巷道的条状结构特点,提出一种基于距离约束的井下目标定位方法。在巷道内每4个锚节点构成1个矩形区域,将固定的两锚节点之间的距离作为约束条件,结合垂直向量乘积为零的原理,矩形对角线的长度已知,通过基于RSSI的测距原理获得移动节点到矩形区域两对角线上锚节点的距离之比公式,进而通过合理的近似运算和向量乘法定理得到向量方程组,通过求解向量方程组可以得到移动节点的坐标,仿真实验表明该方法可以有效地降低定位误差。

关键词：距离约束矿井目标定位 RSSI