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Kinetic Resolution of Racemic 4-Substituted Chroman-2-ones Through Asymmetric Lactone Hydrogenation

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CCS Chemistry 2024年第10期6卷 2560-2576页

作者： Xiong Wu Hai-Tao Yue xiao-Dong Zuo xiao-Hui yang Pu-Cha Yan Jian-Hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryFrontiers Science Center for New Organic MatterNankai UniversityTianjin 300071 Zhejiang Jiuzhou Pharmaceutical Co. Ltd.TaizhouZhejiang 318000

Esters are abundant in natural and synthetic products and their conversion into primary alcohols holds great importance in fine chemical ***,achieving asymmetric hydrogenation(AH)of racemic esters with remote stereocenters via kinetic resolution(KR)remains a formidable challenge due to the difficulties associated with discerning spatially distant *** address this issue,we have designed a hydroxy-assisted strategy that introduces a hydroxy group into racemicβ-aryl esters to facilitate hydrogenation and enhance chiral discrimination through a lactone *** employing chiral Ir-SpiroPAP catalysts,we achieved exceptional AH of racemic 4-substituted chroman-2-ones,lactone form of ortho-hydroxylatedβ-aryl esters,via KR,resulting in impressive selectivity factor(s)values of up to *** approach exhibited significant efficacy for racemic chroman-2-ones containingβ-aryl,alkenyl,alkynyl,and alkyl groups,enabling the synthesis of chiralγ-aryl primary alcohols and the recovery of chiralβ-aryl esters or chroman-2-ones,typically difficult to access using existing *** scalability and broad synthetic applications of this method were exemplified by successfully synthesizing chiral drugs(R)-fesoterodine and enrasentan,alongside various chiral intermediates essential for producing chiral drugs and natural *** promising results highlight the potential of this approach as a powerful tool for synthesizing valuable chiral compounds.

关键词： asymmetric hydrogenation chiralγ-aryl primary alcohols hydrogenation of esters iridium catalysts kinetic resolution

Correlation between serum markers and transjugular intrahepatic portosystemic shunt prognosis in patients with cirrhotic ascites

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 481-490页

作者： xiao-Gang Hu xiao-Xian yang Jun Lu Gang Li Jian-Ji Dai Jia-Min Wang Yi Deng Rui Feng Department of Interventional Radiology The Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000Zhejiang ProvinceChina Medical College Jinhua PolytechnicJinhua 321017Zhejiang ProvinceChina Department of Interventional Medicine Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Individuals with refractory ascites in the context of liver cirrhosis typically face an adverse *** transjugular intrahepatic portosystemic shunt(TIPS)is an efficacious intervention,but there is a lack of reliable tools for postoperative pro-gnosis *** utilized clinical biochemical markers,such as the serum albumin concentration(Alb),sodium(Na+)concentration,and serum creatinine(Scr),have limited predictive ***,the quest for novel,specific biomarkers to evaluate the post-TIPS prognosis in patients with liver cirrhosis and refractory ascites holds significant practical importance.A retrospective analysis was conducted on 75 patients with liver cirrhosis and refractory ascites who underwent TIPS at our institution from August 2019 to August *** patients were followed up regularly for two years,and the death toll was meticulously *** patients were allocated into a survival group(n=45 patients)or a deceased group(n=30 patients)based on their prognosis *** clinical data of the two groups were collected,and Child-Pugh scores and MELD scores were calculated for *** correlation analysis was carried out to evaluate the correlation of prognosis with Child-Pugh grade,MELD score,and Cys C ***,a multiple-factor analysis utilizing the Cox proportional hazard model was used to identify independent risk factors affecting the post-TIPS prognosis of patients with liver cirrhosis and refractory *** receiver operating characteristic curve(ROC)ascertained the predictive value of the Cys C concen-tration,Child-Pugh grade,and MELD score for the prognosis of liver cirrhosis with refractory ascites in post-TIPS *** During a 2-year follow-up period,among 75 patients with liver cirrhosis and refractory ascites who underwent TIPS treatment,30 patients(40.00%)passed *** deceased cohort exhibited heightened aspartate aminotrans-ferase,alanine aminotransferase,total b

关键词： Liver cirrhosis Refractory ascites Transjugular intrahepatic portosystemic shunt Cystatin C

A deep learning interatomic potential suitable for simulating radiation damage in bulk tungsten

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Tungsten 2024年第2期6卷 304-322页

作者： Chang-Jie Ding Ya-Wei Lei xiao-yang Wang xiao-Lin Li Xiang-Yan Li Yan-Ge Zhang Yi-Chun Xu Chang-Song Liu Xue-Bang Wu Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island University of Science and Technology of ChinaHefei 230026China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

So far, it has been a challenge for existing interatomic potentials to accurately describe a wide range of physical properties and maintain reasonable efficiency. In this work, we develop an interatomic potential for simulating radiation damage in body-centered cubic tungsten by employing deep potential, a neural network-based deep learning model for representing the potential energy surface. The resulting potential predicts a variety of physical properties consistent with first-principles calculations, including phonon spectrum, thermal expansion, generalized stacking fault energies, energetics of free surfaces, point defects, vacancy clusters, and prismatic dislocation loops. Specifically, we investigated the elasticity-related properties of prismatic dislocation loops, i.e., their dipole tensors, relaxation volumes, and elastic interaction energies. This potential is found to predict the maximal elastic interaction energy between two 1/2 loops better than previous potentials, with a relative error of only 7.6%. The predicted threshold displacement energies are in reasonable agreement with experimental results, with an average of 128 eV. The efficiency of the present potential is also comparable to the tabulated gaussian approximation potentials and modified embedded atom method potentials, meanwhile, can be further accelerated by graphical processing units. Extensive benchmark tests indicate that this potential has a relatively good balance between accuracy, transferability, and efficiency.

关键词： Machine learning Deep learning Interatomic potential Radiation damage Tungsten

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 481-486页

作者： Xin Huang Qian Lu Yue-Wei Zhang Lin Zhang Zhi-Zhong Ren xiao-Wei yang Ying Liu Rui Tang Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

关键词： Cavernous transformation of the portal vein Classification Direct portal venography Intrahepatic portal venous system

1841—1842年西藏抗击查谟入侵之战的军事地理分析

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地理科学进展 2024年第8期43卷 1609-1616页

作者：杨霄复旦大学历史地理研究中心上海200433

中国西藏阿里地区海拔高、山岳连绵、峡谷交错,严酷的地理环境成为开展军事活动的限制性因素。1841—1842年,这里曾发生西藏抗击查谟入侵的战争,与当前中印两国边界争议息息相关。论文借助多学科的研究路径和军事地理分析框架,分析军事... 详细信息

中国西藏阿里地区海拔高、山岳连绵、峡谷交错,严酷的地理环境成为开展军事活动的限制性因素。1841—1842年,这里曾发生西藏抗击查谟入侵的战争,与当前中印两国边界争议息息相关。论文借助多学科的研究路径和军事地理分析框架,分析军事地理格局与过程间的相互作用,以及战役的时空机制与结构机制。研究认为,清代后期,西藏阿里地区的军事地理格局发生了显著变化。东提、楚舒勒和什布奇山口三处位置,由后方的交通要道变为军事前沿,其军事地理价值凸显。战争初期,查谟军队通过秘密集结、隐蔽意图,快速通过各险要隘口,达成了战役的突然性。藏军被迫以空间换取时间,在多玉重创查谟军队,进而收复全部失地。但由于藏军的主要作战基地均位于廓尔喀(尼泊尔)方向,从前藏、后藏出击的藏军在到达列城时,已经远离自己的作战基地超过2000 km。从时间和距离因素上分析,都难以长期支撑其作战行动。因此,当藏军的攻势超过“顶点”时,“核心—边缘”结构发生转化,藏军由优势转为劣势,不得不从拉达克撤退。论文通过军事地理分析,揭示了军事地理环境与战争间的关系,提出了准备和实施战争的关键区域,对于当前的国防建设具有重要的借鉴意义。

关键词：西藏阿里地区查谟拉达克军事地理克什米尔

Lossless Compression Method for the Magnetic and Helioseismic Imager(MHI)Payload

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Research in Astronomy and Astrophysics 2024年第4期24卷 214-221页

作者： Li-Yue Tong Jia-Ben Lin Yuan-Yong Deng Kai-Fan Ji Jun-Feng Hou Quan Wang xiao yang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

The Solar Polar-orbit Observatory(SPO),proposed by Chinese scientists,is designed to observe the solar polar regions in an unprecedented way with a spacecraft traveling in a large solar inclination angle and a small ***,one of the most significant challenges lies in ultra-long-distance data transmission,particularly for the Magnetic and Helioseismic Imager(MHI),which is the most important payload and generates the largest volume of data in *** this paper,we propose a tailored lossless data compression method based on the measurement mode and characteristics of MHI *** background out of the solar disk is removed to decrease the pixel number of an image under *** predictive coding methods are combined to eliminate the redundancy utilizing the correlation(space,spectrum,and polarization)in data set,improving the compression *** results demonstrate that our method achieves an average compression ratio of *** compression time is also less than the general observation *** method exhibits strong feasibility and can be easily adapted to MHI.

关键词： methods:data analysis techniques:image processing Sun:magnetic fields Sun:photosphere

Unprecedented sesquiterpene-polycyclic polyprenylated acylphloroglucinol adduct against acute myeloid leukemia via inhibiting mitochondrial complex Ⅴ

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Chinese Chemical Letters 2024年第10期35卷 305-308页

作者： Zhengyi Shi Jie Yin yang xiao Zhangrong Hou Fei Song Jianping Wang Qingyi Tong Changxing Qi Yonghui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science andTechnologyWuhan430030China

Monosescinol A(1),the first example of sesquiterpene–polycyclic polyprenylated acylphloroglucinol(PPAP)adduct,which represented a new subclass of PPAP-type natural products,along with two new congeners with normal spiro 6/6/5 tricyclic architecture,were isolated from Hypericum *** A possessed an unprecedented 6/5/5/6/6 pentacyclic carbon skeleton that might be assembled from the 6/6/5 carbon skeleton,via the splitting decomposition of C-3/C-14,and the attack from the C-3 in the PPAP core to C-28 in sesquiterpene *** addition,we have firstly confirmed that 24R configuration was existed in sec–Bu containing PPAPs by single crystal diffraction data analysis of monosescinol B(2),that might provide an enlightenment in the configurational determination of sec–Bu containing ***,further pharmacological research has found that compound 1 exhibited remarkable pharmacological effects against acute myeloid leukemia(AML)cell lines,with direct inhibition of mitochondrial complex V and an increase in mitochondrial membrane potential,and led to an induction of oxidative stress,endogenous inflammation,and apoptosis of AML cells.

关键词： PPAP adduct Single-crystal X-ray diffraction Keto-enol tautomerism Plausiblebiosynthetic pathway Cytotoxic activity

Systematic Evaluation of Guidelines for the Diagnosis and Treatment of Hepatitis E Virus Infection

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Journal of Clinical and Translational Hepatology 2024年第8期12卷 739-749页

作者： Ting Gu Cai-Ying Zheng Yan-Qin Deng xiao-Feng yang Wei-Min Bao Ying-Mei Tang Department of Gastroenterology Second Affiliated Hospital of Kunming Medical UniversityKunming Medical UniversityKunmingYunnanChina Second Affiliated Hospital of Kunming Medical University KunmingYunnanChina Department of Colorectal Surgery The First People’s Hospital of Yunnan ProvinceKunmingYunnanChina

Background and Aims:The hepatitis E virus(HEV)is a zoonotic disease,and infection with HEV in humans primarily causes acute infections and can progress to chronic manifestation in immunocompromised *** the past decade,guidelines for diagnosing and treating HEV infection have been *** study aimed to systematically assess the quality of current guidelines for diagnosing and treating HEV infection,and we analyzed the differences in guideline quality and primary recommendations and explored possible reasons for these ***:Guidelines published between 2013 and 2022 were searched,and studies were identified using selection *** study assessed the quality of the included guidelines using the Appraisal of Guidelines for Research and Evaluation tool,extracted the primary recommendations in the guidelines,determined the highest level of evidence supporting the recommendations,and reclassified the evidence using the Oxford Centre for Evidence-Based Medicine grading ***:Seven guidelines were included in the final *** quality of the guidelines varied *** discrepancies may have been caused by the lack of external experts,the failure to consider influencing factors in guideline application,and the lack of consideration of the public’s *** of the heterogeneity in primary recommendations revealed differences in algorithms for managing chronic HEV infection,the dosage of ribavirin,and a low level of evidence supporting the primary ***:Guideline quality and primary recommendations vary *** by guideline developers and researchers would facilitate updating and applying guidelines for diagnosing and treating HEV infection.

关键词： Hepatitis E virus Guidelines Diagnosis Treatment Systematic Evaluation

Nanopore design of sulfur doped hollow carbon nanospheres for superior potassium-ion battery anodes

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Rare Metals 2024年第5期43卷 2103-2114页

作者： Zhen-Dong Liu Hui-Yan Feng Yu-Chen Wang Fei Wang Yue Liu Jian-xiao yang Yue Gu Jun Tan Chong Ye Cheng-Zhi Zhang Ji Hua Laboratory Foshan 528000China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology College of Materials Science and EngineeringHunan UniversityChangsha 410082China

Sulfur doped carbonaceous materials are promising anodes for potassium-ion batteries because of their ability to bridge active sites and induce C/S electron coupling,resulting in increased ion storage capacitance However,the large potassium ions could cause significant volume expansion and structure collapse during operation in sulfur doped carbonaceous anodes,which lead to rapidly capacity sacrifice during long-term *** design for anchoring sulfur atom in carbon skeleton is a novel way to alleviate the structure collapse and maintain the cycling ***,this study developed a controlled nanopore and sulfur doped carbon sphere structure(S-NPHCSs).In potassium-ion batteries S-NPHCSs anode demonstrated exceptional performance with a high reversible capacity of 247 mAh·g^(–1)after 50 cycles at 0.2 A·g^(–1)and delivered a long cycle stability of 600 cycles at a high current density of 1.0 A·g^(–1).Interconnected nanopores and doped sulfur structure not only expand the accumulation space and offer ample active sites for diffusion and adsorption of potassium ions,but also build stable channels through nanopore structure to ensure the cyclic *** finding provides a fundamental theory for designing nanopore structures and introducing sulfur doped carbonaceous materials to enhance capacitive potassium storage and long cycle stability.

关键词： Nanopore Carbon materials Sulfur doping Anode Potassium-ionbatteries