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基于分叉修正面跳跃轨线的绝热和透热布居计算方法

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Chinese Journal of Chemical Physics 2022年第3期35卷 488-498,I0002页

作者：郭欣徐佳波李桂杰王林军浙江大学化学系浙江省激发态材料合成与应用重点实验室杭州310027

对标准散射问题的非绝热动力学模拟,分叉修正面跳跃已被证明是一种可提高传统最少面跳跃性能的可靠方法[***.150,164101(2019)].本文研究了如何分析分叉修正面跳跃轨线,以得到可靠的绝热和透热布居.研究了一系列一维二能级散射模型,以... 详细信息

对标准散射问题的非绝热动力学模拟,分叉修正面跳跃已被证明是一种可提高传统最少面跳跃性能的可靠方法[***.150,164101(2019)].本文研究了如何分析分叉修正面跳跃轨线,以得到可靠的绝热和透热布居.研究了一系列一维二能级散射模型,以量子精确解和最少面跳跃结果为参考,发现分叉修正面跳跃方法可以得到接近精确解的含时布居.特别地,不同的轨线分析方法在不同的表象下会得到明显不同的结果.具体来说,轨线占据数方法在计算绝热态布居时表现更好,而波函数方法可以得到更可靠的透热态布居.

关键词：面跳跃轨线分析含时布居分叉修正

Surface Hopping Methods for Nonadiabatic Dynamics in Extended Systems

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Surface Hopping Methods for Nonadiabatic Dynamics in Extende...

Surface Hopping Methods for Charge Transport in Hundreds of Molecules

第十六届全国化学动力学会议

作者： linjun wang Department of Chemistry Zhejiang University

Due to the ease of implementation and good balance between efficiency and reliability, surface hopping has become one of the most widely used mixed quantum-classical methods for studying general charge and exciton dynamics.1 In extended systems（e.g., aggregates, polymers, surfaces, interfaces, and solids）, however, surface hopping suffers from several severe problems, and thus the relevant applications have been limited in the past years.2 Trivial crossings between uncoupled or weakly coupled states have highly peaked nonadiabatic couplings and thus are difficult to deal with in the preferred, adiabatic representation.3 Recently, we systematically classify surface crossings within a time step into four general types and proposed a parameter-free crossing corrected FSSH（CC-FSSH） method to describe the complex nonadiabatic dynamics with a high density of states.4 We further showed that a proper choice of subspace can significantly simplify the surface crossings and further increase the performance.5 Fast time step convergence and system size independence in systems with thousands of molecular sites have been achieved. In addition, we proposed a branching corrected surface hopping（BCSH） method, which resets the wavefunction coefficients based on the judgement of wave packet reflection.6 This approach ensures the self-consistency of using the traditional timedependent Schr?dinger equation for mixed quantum-classical dynamics. As benchmarked in over two hundred distinct scattering models, BCSH has captured the majority of the real decoherence effect, surpassing other existed decoherence correction algorithms. With our recent method developments, complex nonadiabatic dynamics in extended systems could be simulated with improved efficiency and reliability, thus promising for many applications in chemistry, physics, biology, and material sciences.7

关键词： nonadiabatic dynamics trajectory surface hopping extended systems crossing correction decoherence correction

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Surface Hopping Methods for Charge Transport in Hundreds of ...

第十三届全国量子化学会议

作者： linjun wang Department of Chemistry Zhejiang University

In the past years, surface hopping[1] has been widely applied to study charge and exciton dynamics in various semiconductors and interfaces.[2] For large-scale simulations like charge transport, surface hopping suffers severely from the trivial crossing problem,[3] arising due to the high density of adiabatic potential energy surfaces. We realized that trivial crossings can easily induce artificial long-range charge transfer,and even a very small portion of trivial crossings is likely to make surface hopping results completely meaningless.[4-5] With a QM/MM-like idea, the flexible surface hopping（FSH） treats only the charge and its surrounding nuclear vibrations with surface hopping, and reproduces the crossover from hopping to band-like transport for the first time.[3] Recently, the self-consistent fewest switches surface hopping（SC-FSSH）[6] has been proposed. It corrects the problematic surface hopping probabilities with the self-consistency of charge populations, and gives a more robust and clean description of trivial crossings. SC-FSSH has shown a high accuracy in small molecular aggregates.[6] Recently, we systematically investigate the performance of SC-FSSH in charge transport with hundreds of molecules. We found that the charge mobility converges very quickly with the time interval. Even a time interval as small as 0.2 fs is able to give the converged mobility. SC-FSSH also reproduces the band-to-hopping crossover and predicts the correct scaling for Marcus’ golden-rule *** to the robustness of SC-FSSH, we also build approximate surface hopping methods using SC-FSSH as a reference. When we neglect the feedback of electron to nuclei[7], the error of mobility is only ～15% when the room-temperature mobility exceeds 6×10-3 cm2/Vs in 1D molecular stacks. SC-FSSH and the related methods have shown great accuracy and efficiency in describing charge transport, and should be promising for general large-scale nonadiabatic dynamics of charges and excitons.

关键词： surface hopping charge transport trivial crossing problem

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胃癌根治术后少见并发症的防治

中华胃肠外科杂志 2023年第2期26卷 138-143页

作者：刘宏达王林俊徐泽宽南京医科大学第一附属医院普通外科南京210029

胃癌根治术后并发症种类繁多,影响因素复杂,常见并发症的预防与诊治已有较多文献报道。然而,针对少见并发症防治的报道较少。胃癌根治术后少见并发症因其发生率低,常常不被重视。因此,临床医师对胃癌根治术后少见并发症的预防、诊断及... 详细信息

胃癌根治术后并发症种类繁多,影响因素复杂,常见并发症的预防与诊治已有较多文献报道。然而,针对少见并发症防治的报道较少。胃癌根治术后少见并发症因其发生率低,常常不被重视。因此,临床医师对胃癌根治术后少见并发症的预防、诊断及治疗缺乏经验,亦缺少相关的指南和专家共识,这也给少见并发症的诊治和预防带来了困难。本文结合文献回顾及笔者的经验,就胃癌根治术后7种少见并发症(十二指肠残端瘘、胰瘘、乳糜漏、食管纵隔瘘、腹内疝、胃瘫、肠套叠)进行系统性阐述,以期为胃癌根治术后少见并发症的诊治和预防提供参考。

关键词：胃癌根治术十二指肠残端瘘胰瘘乳糜漏食管纵隔瘘腹内疝胃瘫肠套叠

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保留功能胃切除术在胃癌根治术中的研究进展

中华消化外科杂志 2023年第3期22卷 332-337页

作者：徐泽宽王林俊李博文南京医科大学第一附属医院普通外科南京210029

随着健康理念普及和胃镜检查技术的进步,我国早期胃癌确诊比例呈逐年上升趋势。早期胃癌具有良好的预后和长期生存时间,提高早期胃癌患者的术后生命质量成为胃癌研究的重点方向之一。因此,在保证肿瘤根治的前提下,以提高患者生命质量为... 详细信息

随着健康理念普及和胃镜检查技术的进步,我国早期胃癌确诊比例呈逐年上升趋势。早期胃癌具有良好的预后和长期生存时间,提高早期胃癌患者的术后生命质量成为胃癌研究的重点方向之一。因此,在保证肿瘤根治的前提下,以提高患者生命质量为目的保留功能胃切除术成为早期胃癌治疗的热点议题。近年来,随着对胃癌淋巴结转移规律研究的深入,保留功能胃切除术的应用范围已逐渐向进展期胃癌拓展。保留功能的胃切除术包括节段胃切除术、近端胃切除术和局部胃切除术。笔者围绕近年来保留功能胃切除术的国内外重要研究进展以及笔者团队实践经验进行归纳和总结,期望为临床外科医师开展保留功能胃切除术提供参考。

关键词：胃肿瘤保功能胃切除术吻合方式并发症生命质量

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电极对CdZnTe光电探测器性能的影响

上海大学学报（自然科学版） 2023年第4期29卷 796-802页

作者：师好智王林军上海天交机电科技有限公司上海200443 上海大学材料科学与工程学院上海200444

CdZnTe材料具有较宽的禁带宽度和化学稳定性,使其成为制备紫外光电探测器的理想材料.电极与CdZnTe材料之间良好的接触特性对制备高灵敏度和高稳定性的紫外探测器具有关键作用.制备了单电极Au/CdZnTe/Au探测器和复合电极Au/GaZnO(GZO)/Cd... 详细信息

CdZnTe材料具有较宽的禁带宽度和化学稳定性,使其成为制备紫外光电探测器的理想材料.电极与CdZnTe材料之间良好的接触特性对制备高灵敏度和高稳定性的紫外探测器具有关键作用.制备了单电极Au/CdZnTe/Au探测器和复合电极Au/GaZnO(GZO)/CdZnTe/GZO/Au探测器,研究了不同电极对CdZnTe紫外光电探测器性能的影响.

关键词： CdZnTe 电极光电探测器紫外线探测器接触特性

Dynamic intrauterine crosstalk promotes porcine embryo implantation during early pregnancy

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Science China(Life Sciences) 2024年第8期67卷 1676-1696页

作者： Xupeng Zang Shengchen Gu Wenjing wang Junsong Shi Jianyu Gan Qun Hu Chen Zhou Yue Ding Yanjuan He Lei Jiang Ting Gu Zheng Xu Sixiu Huang Huaqiang Yang Fanming Meng Zicong Li Gengyuan Cai linjun Hong Zhenfang Wu State Key Laboratory of Swine and Poultry Breeding Industry National Engineering Research Center for Breeding Swine IndustryCollege of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642China Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding South China Agricultural UniversityGuangzhou 510642China Yunfu Subcenter of Guangdong Laboratory for Lingnan Modern Agriculture Yunfu 527300China Guangdong Key Laboratory of Animal Breeding and Nutrition Institute of Animal ScienceGuangdong Academy of Agricultural SciencesGuangzhou 510640China Key Laboratory of South China Modern Biological Seed Industry Ministry of Agriculture and Rural AffairsGuangzhou 510520China

Dynamic crosstalk between the embryo and mother is crucial during ***,we comprehensively profile the single-cell transcriptome of pig peri-implantation embryos and corresponding maternal endometrium,identifying 4 different lineages in embryos and 13 cell types in the ***-specific gene expression characterizes 4 distinct trophectoderm subpopulations,showing development from undifferentiated trophectoderm to polar and mural *** expression of genes in different types of endometrial cells illustrates their molecular response to embryos during ***,we developed a novel tool,ExtraCellTalk,generating an overall dynamic map of maternal-foetal crosstalk using uterine luminal proteins as *** cross-species comparisons,we identified a conserved RBP4/STRA6 pathway in which embryonic-derived RBP4 could target the STRA6 receptor on stromal cells to regulate the interaction with other endometrial *** results provide insight into the maternal-foetal crosstalk during embryo implantation and represent a valuable resource for further studies to improve embryo implantation.

关键词： endometrial remodeling ExtraCellTalk implantation maternal-foetal crosstalk trophoblast

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采用花朵授粉算法的等几何边界元形状优化

北京航空航天大学学报 2023年第5期49卷 1148-1155页

作者：高翔王林军刘洋陈保家付君健三峡大学水电机械设备设计与维护湖北省重点实验室宜昌443002 三峡大学机械与动力学院宜昌443002

为了避免离散整个结构,以及减少几何模型与离散模型之间的误差,提出一种改进的花朵授粉算法优化等几何边界元模型的形状优化算法。采用的边界元法仅需离散结构边界,简化了离散过程,且加入的等几何分析可提高计算精度。以最小化位移或应... 详细信息

为了避免离散整个结构,以及减少几何模型与离散模型之间的误差,提出一种改进的花朵授粉算法优化等几何边界元模型的形状优化算法。采用的边界元法仅需离散结构边界,简化了离散过程,且加入的等几何分析可提高计算精度。以最小化位移或应力为目标函数,以结构面积等于指定面积为约束条件,采用增广乘子法将约束优化模型转化为无约束优化模型;通过等几何边界元法对结构的受力情况进行分析;采用精英反向学习策略及大规模分布估计算法(LSEDA)改进花朵授粉算法,通过花朵授粉算法优化控制点的坐标值,并通过非均匀有理B样条(NURBS)基函数构建结构的边界,输出最优结构的形状。Ackley函数的测试结果表明:改进的花朵授粉算法14步收敛,而原始花朵授粉算法136步收敛,且所得最小值为8.8818×10^(-16),小于0.0014,改进的花朵授粉算法寻优能力更强。形状优化的计算结果表明:所提算法可有效求解二维等几何边界元形状优化问题。

关键词：花朵授粉算法等几何分析边界元法形状优化莱维飞行分布估计算法

Hypoxia-inducible factor-lαand semaphorin4D genes involved with tumor-associated macrophage-induced metastatic behavior and clinical significance in colon cancer

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Chinese Medical Journal 2014年第20期 3568-3575页

作者： Mu linjun wang Jinshen Chen Yuezhi Li Leping Guo Xiaobo Zheng Sheng Jing Changqing Department of Gastrointestinal Surgery Shandong Provincial Hospitalaffiliated to Shandong University Jinan Shandong 250021 China

Background Hypoxia promotes tumor angiogenesis and hypoxia-inducible factor-1 alpha （HIF-lg） plays a pivotal role in this process. Recently identified pro-angiogenic factor, semaphorin4D （Sema4D） also promotes angiogenesis and enhances invasive proliferation in some tumors. Furthermore, tumor-associated macrophages （TAMs） can increase the expression of HIF-la and Sema4D in cancer cells and thus influence tumor growth and progression. The purpose of this study was to evaluate the effect of TAMs on the expression of Sema4D and HIF-la and the impact of biologic behavior in colon cancer cells. Methods Immunohistochemistry was used to analyze HIF-la and Sema4D expression in 86 curatively resected colon cancer samples and 52 normal colon tissues samples. The relationship between their expression and clinicopathological factors was analyzed. Furthermore, macrophage-tumor cell interactions, such as metastasis, angiogenesis, were also studied using in vitro co-culture systems. Statistical analysis was performed using SPSS 17.0 software （SPSS Inc., USA）. Differences between two groups were analyzed with Student＇s t test. Results HIF-la （58%） and Sema4D （60%） were expressed at a significantly higher level in tumors than in normal tissues （P 〈0.01, for both）. Furthermore, HIF-la and Sema4D expression was significantly correlated with lymphatic metastasis, specific histological types and TNM stages （P 〈0.05）, but not with age and tumor size （P 〉0.05）. Sema4D expression was correlated with that of HIF-la （r=0.567, P 〈0.01）. TAMs markedly induced HIF-la and Sema4D expression in colon cancer calls and subsequently increased their migration and invasion. Conclusions HIF-la and Sema4D expression are closely related to lymphatic metastasis, specific histological types and TNM stages in colon cancer. Furthermore, TAMs promote migration and invasion of colon cancer cells and endothelial tube formation, possibly through up-regulation of HIF-la and Sema4D.

关键词： colon cancer hypoxia-inducible factor-1 alpha semaphorin4D tumor-associated macrophages metastasis