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Asymmetric synthesis of binaphthyls through photocatalytic crosscoupling and organocatalytic kinetic resolution

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Science China Chemistry 2022年第6期65卷 1142-1148页

作者： Heng-Hui Li Jia-Yan Zhang Shaoyu Li Yong-Bin Wang jun kee cheng Shao-Hua Xiang Bin Tan School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin150001China Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China

By capitalizing on the capability of photoredox catalysis to generate reactive radical intermediate under mild conditions, we established a photocatalytic cross-coupling protocol that could deliver both derivatives from 1-bromo-2-naphthols in combination with 2-naphthols or 2-naphthylamines. This distinct activation mode could overcome structural or electronic limitation associated with conventional coupling pathways. Additionally, a novel kinetic resolution protocol of unprotected BINOLs has been established with azodicarboxylates via chiral phosphoric acid(CPA) catalysis. Selectivity factor of up to 175 could be achieved and delivered to both enantiomers in atropisomerically enriched form after a simple work-up.

关键词： 1 1′-bi-2-naphthols 2-amino-2′-hydroxy-1 1′-binaphthyls chiral phosphoric acid kinetic resolution photocatalysis

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Antiviral therapy for hepatitis B virus infection is beneficial for the prognosis hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 1-9页

作者： Hui Wan Yu-Xin Zhang Guan-Yue Shan jun-Ya cheng Duan-Rui Qiao Yi-Ying Liu Wen-Na Shi Hai-jun Li Institute of Translational Medicine The First Hospital of Jilin UniversityChangchun 130061Jilin ProvinceChina Department of Bioengineering Pharmacy School of Jilin UniversityChangchun 130061Jilin ProvinceChina Institute of Liver Diseases Institute of Translational MedicineThe First Hospital of Jilin UniversityChangchun 130061Jilin ProvinceChina

In this editorial,we comment on the article by Mu et al,published in the recent issue of the World Journal of Gastrointestinal *** pay special attention to the immune tolerance mechanism caused by hepatitis B virus(HBV)infection,the pathogenesis of hepatocellular carcinoma(HCC),and the role of antiviral therapy in treating HCC related to HBV *** infection leads to systemic innate immune tolerance by directly inhibiting pattern recognition receptor recognition and antiviral signaling pathways,as well as by inhibiting the immune functions of macrophages,natural killer cells and dendritic *** addition,HBV leads to an immunosuppressive cascade by expressing inhibitory molecules to induce exhaustion of HBV-specific cluster of differentiation 8+T cells,ultimately leading to long-term viral *** loss of immune cell function caused by HBV infection ultimately leads to ***-term antiviral therapy can improve the prognosis of patients with HCC and prevent tumor recurrence and metastasis.

关键词： Hepatitis B virus Hepatocellular carcinoma Hepatitis B virus-DNA Immune tolerance Antiviral therapy

理论探索二维X_(2)UO_(4)(X=K,Rb,Cs)的力学特征、电子结构和声子输运特征

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原子与分子物理学报 2025年第2期42卷 143-150页

作者：程钧湖北医药学院研究生院十堰442000

本文用基于密度泛函理论的第一性原理计算方法,研究了三种建议的二维材料X_(2)UO_(4)(X=K,Rb,Cs)的稳定性、弹性、电子结构和声子振动特性.计算结果显示,三种材料同时具备较好的热力学、动力学和机械稳定性.电子结构表明,三种材料属于... 详细信息

本文用基于密度泛函理论的第一性原理计算方法,研究了三种建议的二维材料X_(2)UO_(4)(X=K,Rb,Cs)的稳定性、弹性、电子结构和声子振动特性.计算结果显示,三种材料同时具备较好的热力学、动力学和机械稳定性.电子结构表明,三种材料属于宽禁带间接半导体,其计算能隙分别是3.90、3.79和3.42 eV,并且在300 K时有着71.31-174.23 cm^(2)/Vs的电子迁移率.声子输运特性表明,三种材料的声子色散均没有虚频出现,声学模和低频光学模呈现强烈耦合,且有着低频率low-lying声子,这使得材料具备很强的声子非谐效应、低声子群速度和强声子散射率,从而表现出很低晶格热导率,在300 K温度下时仅为0.16-0.19 W/mK.这些特性表明,二维X_(2)UO_(4)(X=K,Rb,Cs)在纳米电子和热电器件领域具备应用潜力.

关键词：二维材料能带迁移率声子热导率

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-cheng Li De-cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Poorly controlled type II diabetes mellitus significantly enhances postoperative chemoresistance in patients with stage III colon cancer

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World Journal of Gastroenterology 2025年第3期31卷 29-41页

作者： Ruo-Yu Guan Jia-Wei Wu Zi-Yun Yuan Zhi-Yuan Liu Zi-Zhu Liu Zhi-Cong Xiao Jing-Hui Li cheng-Zhi Huang jun-Jiang Wang Xue-Qing Yao Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesSouthern Medical UniversityGuangzhou 510080Guangdong ProvinceChina Department of Gastrointestinal Surgery Department of General SurgeryGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina Department of General Surgery Guangdong Provincial People’s Hospital Ganzhou Hospital(Ganzhou Municipal Hospital)Ganzhou 341000Jiangxi ProvinceChina Shantou University Medical College Shantou 515041Guangdong ProvinceChina School of Medicine South China University of TechnologyGuangzhou 510006Guangdong ProvinceChina Gannan Medical University Ganzhou 341000Jiangxi ProvinceChina

BACKGROUND Type II diabetes mellitus(T2DM)has been associated with increased risk of colon cancer(CC)and worse prognosis in patients with *** effects of T2DM on postoperative chemoresistance rate(CRR)and long-term disease-free survival(DFS)and overall survival(OS)in patients with stage III CC who receive curative resection remain *** To investigate whether T2DM or glycemic control is associated with worse postoperative survival outcomes in stage III *** This retrospective cohort study included 278 patients aged 40-75 years who underwent surgery for stage III CC from 2018 to *** on preoperative T2DM history,the patients were categorized into non-DM(n=160)and DM groups(n=118).The latter was further divided into well-controlled(n=73)and poorly controlled(n=45)groups depending on the status of glycemic ***,OS,and CRR were compared between the groups and Cox regression analysis was used to identify risk *** Patients in the DM and non-DM groups demonstrated similar DFS,OS,and CRR(DFS:72.03%vs 78.75%,P=0.178;OS:81.36%vs 83.12%,P=0.638;CRR:14.41%vs 7.5%,P=0.063).Poorly controlled DM was associated with a significantly worse prognosis and higher CRR than well-controlled DM(DFS:62.22%vs 78.07%,P=0.021;OS:71.11%vs 87.67%,P=0.011;CRR:24.40%vs 8.22%,P=0.015).High preoperative fasting plasma glucose[DFS:Hazard ratio(HR)=2.684,P<0.001;OS:HR=2.105,P=0.019;CRR:HR=2.214,P=0.005]and glycosylated hemoglobin levels(DFS:HR=2.344,P=0.006;OS:HR=2.119,P=0.021;CRR:HR=2.449,P=0.009)indicated significantly poor prognosis and high CRR,while T2DM history did not(DFS:HR=1.178,P=0.327;OS:HR=0.933,P=0.739;CRR:HR=0.997,P=0.581).CONCLUSION Increased preoperative fasting plasma glucose and glycosylated hemoglobin levels,but not T2DM history,were identified as risk factors associated with poor postoperative outcomes and high CRR in patients with stage III CC.

关键词： Colon cancer Chemoresistance Diabetes mellitus Prognosis Type II diabetes mellitus

肌肉负荷对股骨干骨折早期愈合生物力学影响的有限元分析

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中国组织工程研究 2025年第21期29卷 4413-4420页

作者：程超然张峻霞贾军天津科技大学机械工程学院天津市300222 天津市轻工与食品工程机械装备集成设计与在线监控重点实验室天津科技大学天津市300222 天津市天津医院骨科天津市300200

背景:以往的研究多通过忽略肌肉负荷和采用简化股骨负荷的方式,进行骨折早期愈合的生物力学分析。然而,肌肉负荷对骨折早期愈合产生的生物力学影响尚不清楚。目的:构建不同的股骨负荷模型,研究肌肉负荷对骨折愈合的生物力学影响,帮助临... 详细信息

背景:以往的研究多通过忽略肌肉负荷和采用简化股骨负荷的方式,进行骨折早期愈合的生物力学分析。然而,肌肉负荷对骨折早期愈合产生的生物力学影响尚不清楚。目的:构建不同的股骨负荷模型,研究肌肉负荷对骨折愈合的生物力学影响,帮助临床医生更好地理解骨折愈合的生物力学过程,优化治疗方案。方法:利用AnyBody Modeling System软件构建个性化的人体肌肉骨骼系统,通过仿真分析以获取体内的肌肉骨骼负荷模型。该模型和采用改进简化负荷方法、简化负荷方法构建的股骨负荷模型,分别作为有限元输入的边界条件,对站立状态下锁定加压钢板应力应变、骨折块应变进行分析。结果与结论:(1)与简化负荷方法相比,肌肉骨骼方法得到的锁定加压钢板应力、应变和骨折块应变分别小了31.9%;38.9%和19.5%;(2)肌肉骨骼方法与改进简化负荷方法对比发现,忽略肌肉负荷则会造成锁定加压钢板的应力、应变和骨折块应变分别高估16.8%,14.3%和19.5%,肌肉负荷对骨折块的剪切运动大小无明显影响,而对运动方向有明显的影响;(3)结果表明,简化股骨负荷和忽略肌肉负荷的方法与肌骨骨骼负荷情况存在一定的偏差,因此,在研究骨折愈合时需考虑肌肉负荷的生物力学影响。

关键词：肌肉负荷骨折愈合锁定加压钢板骨折块应变有限元分析

A high performance approach for solving the high voltage direct current ion flow field problem by tensor-structured finite element method

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High Voltage 2023年第1期8卷 128-137页

作者： Qiwen cheng jun Zou Department of Electrical Engineering Tsinghua UniversityBeijingChina

In order to achieve high performance for solving the ion flow field problem,an approach is proposed with the tensor-structured finite element method(FEM)to accelerate the Newton *** Poisson equation and the continuity equation are reformulated into the tensor expressions,*** element level evaluation phase is decomposed into the concatenated tensor contraction operations,which is implemented by the highly optimised arithmetic operation provided in *** contrast to the traditional implemented FEM,the tensor-structured FEM has significantly improved the throughput and achieved high *** accuracy and efficiency of the tensorbased algorithm are verified under the unipolar and bipolar model,*** tensor-based algorithm provides one order of magnitude speedup over the traditional algorithm in the elemental evaluation phase.‘Tensorization’is an efficient way to bridge the algorithm and the hardware.

关键词： tensor element finite

Foldcore Structures with Origami Initiators for Energy-Absorbing Sandwich Panels

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Acta Mechanica Solida Sinica 2023年第4期36卷 491-505页

作者： jun cheng Yang Li The Institute of Technological Sciences Wuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China

Origami foldcore structures can be used in thin-walled sandwich panels to provide unique advantages over traditional honey-comb *** instance,their continuously connected space is available for flowing through cooling liquid or compact pipeline ***,origami foldcores suffer from relatively low-energy *** paper proposes a new design of energy-absorbing foldcore structures for sandwich panels,including the geometric design,experimental tests,numerical parametric study,and theoretical estimation of energy *** initiators are introduced to the Miura foldcores to induce a failure mode with more transverse folds,which is not common for regular foldcore *** a result,60%higher energy absorption and tunable load uniformity can be achieved.

关键词： Thin-walled structures Sandwich panels Energy absorption Origami Foldcores

Orientation of LDPE Crystals from Microscale to Nanoscale via Microlayer or Nanolayer Coextrusion

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Chinese Journal of Polymer Science 2016年第12期34卷 1411-1411,1412-1422页

作者： jun-feng cheng 浦鸿汀 School of Materials Science and Engineering Tongji University

Abstract The microlayer or nanolayer coextrusion of hundreds or thousands of alternating low density polyethylene （LDPE）/polystyrene （PS） microlayers or nanolayers were used to study the orientation of LDPE crystals in the confined quasi-two-dimensional or two-dimensional space. The clear and continuous layer structures from microscale to nanoscale can be found in SEM images. The morphology evolution of LDPE crystals in the confined microlayer or nanolayer can he varied from 3D spherulites, 2D spherulites, stacked edge-on lamellar, to single edge-on lamellar. Due to the orientation of the LDPE crystals, the tensile strength of the films increases obviously when the layer thickness reduces to nanoscale. The 2D small angle X-ray scattering （SAXS） patterns can reflect the average degree of orientation of LDPE in the confined layers. The stacking of LDPE lamellae is suppressed in interlamination and oppositely in parallel to the extrusion direction. The specific orientation function f can be calculated from the patterns. The infrared dichroism further confirms the mutation of the orientation of LDPE crystals from microscale to nanoscale in the confined space.

关键词： Microlayer or nanolayer coextrusion Low density polyethylene Polystyrene Confined space Crystalorientation.