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Science China Chemistry 2024年第2期67卷 542-550页

作者： Min Chen Longqing Yang yuzhen li Yinhe Qu Guihua Pan Xiaoming Feng Xiaohua liu Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed,which exhibits good functional group compatibility,high atomic and step *** protocol utilizes a strategy of synergistic catalysis with a chiral N,N'-dioxide/Ni~Ⅱ complex and an achiral Pd~0 catalyst,generating a series of multisubstituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-,Z/E-and enantioselectivity under mild *** transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product *** studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E-and *** density functional theory(DFT) calculations further demonstrated that multiple C–H···π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state.

关键词： asymmetric allylic alkylation synergistic catalysis vinyl epoxides allyl alcohol multiple weak interactions

In Hangzhou, Seeking Three Poetic Expressions of Architecture

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China Book International 2024年第3期 36-41页

作者： li yuzhen 不详

In Hangzhou,I visited the works of three architects,Wang Shu's Xiangshan Campus,Kengo Kuma's Folk Art Museum,and finally Tadao Ando's Big *** each used different languages-return,fade,and highlight-to articulate three possible relationships between architecture and nature,showing me that the interaction isn't just a straightforward conflict.

关键词： return straight finally

Toll-like receptors 2 polymorphism is associated with psoriasis: A case-control study in the northern Chinese population

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Frigid Zone Medicine 2024年第2期4卷 96-101页

作者： Siyu Hao Yu Zhang Anqi Yin Ying Lyu Nannan Tong Jiangtian Tian yuzhen li Department of Dermatology the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000China The Key Laboratory of Myocardial Ischemia Chinese Ministry of EducationHarbin 150000China Department of Cardiology the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150000China

Background:Psoriasis is a disease caused by genetics and immune system dysfunction,affecting the skin and ***-like receptors(TLRs)play an important role in triggering the innate immune response and controlling adaptive *** role of TLR2 in the progression of psoriasis is not well ***:A case-control study was conducted on a northern Chinese Han population,consisting of psoriasis patients and healthy control *** was performed using the tetra-primer amplification refractory mutation system-polymerase chain reaction(ARMS-PCR),and allele and genotype frequencies of four SNPs in TLR2 were analyzed in 270 psoriasis patients and 246 healthy ***:Four TLR2 SNPs(rs11938228,rs4696480,rs3804099,rs5743699)were genotyped and found to be in linkage *** genotype distributions of rs11938228 and rs4696480 in two groups were in Hardy-Weinberg equilibrium and statistically significant except for the overdominance *** haplotypes ATTC and ATCC were found to be protective against ***:Our study found a correlation between TLR2 genetic variations and the likelihood of psoriasis in northern China.

关键词： Toll-like receptors 2 psoriasis polymorphism susceptibility

Weitiao No.3(微调3号方) enhances the efficacy of anti-programmed cell death protein-1 immunotherapy by modulating the intestinal microbiota in an orthotopic model of gastric cancer mice

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Journal of Traditional Chinese Medicine 2024年第5期44卷 906-915页

作者： HUANG Xiaona li yuzhen ZHU Chenyang ZHU Hengzhou JIANG Chenyu ZHU Xiaodan ZHANG Chencen JIN Chunhui Department of Oncology Wuxi Hospital Affiliated to Nanjing University of Chinese Medicine (Wuxi Hospital of Traditional Chinese Medicine)

OBJECTIVE: To explore the effects of Weitiao No. 3(微调3号方, WD-3) on anti-programmed cell death protein-1(PD-1) immunotherapy in gastric cancer(GC). METHODS: The intestinal microbiota was analyzed by 16S rDNA sequencing of fecal samples from three groups: healthy people(Health), GC patients(GC), and WD-3-treated GC patients(WD-3). Next, we established an orthotopic model of GC mice, which were treated with anti-PD-1, WD-3, or an inoculation of intestinal bacteria. Immune markers CD3, CD4, CD8, and forkhead box protein P3(FOXP3), and the cell proliferation marker Ki67, were evaluated by immunohistochemistry. Cell apoptosis in GC tumors was assessed by terminaldeoxynucleotidyl-transferase-mediated deoxyuridine triphosphate nick end labeling staining. Enzyme-linked immunosorbent assays(EliSAs) were performed to analyze the serum levels of the following cytokines in GC mice: tumor necrosis factor(TNF)-α, interleukin(IL)-2, IL-6, IL-10, interferon(IFN)-γ, and transforming growth factor(TGF)-β. RESULTS: Sequencing data showed that there were significant differences in the composition of the gut microbial community among the three human groups. The gut bacteria in the three groups mainly comprised the phyla Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria. At the genus level, the relative abundances of Bifidobacterium and Coprococcus showed significant decreases in the GC group, and an obvious increase in the WD-3 group, compared with the Health group. Interestingly, the relative abundance of Saccharopolyspora was only detected in the WD-3 group. The results of in vivo experiments in GC mice showed that WD-3 or anti-PD-1 treatment increased the levels of CD3+, CD4+, and CD8+ T cells, but decreased the levels of FOXP3+ regulatory T cells. Furthermore, WD-3 or PD-1 antibody treatment inhibited proliferation and promoted apoptosis of GC tumor cells. EliSA analysis showed that WD-3 or PD-1 antibody treatment facilitated TNF-α, IL-2, and IFN-γ expression, while suppr

关键词： Weitiao No. 3 gastrointestinal microbiome immunotherapy programmed cell death 1 receptor stomach neoplasms

乡村文化振兴视角下脱贫户可持续生计能力提升路径探析

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中州学刊 2024年第5期 48-54页

作者：郑志龙李雨臻郑州大学政治与公共管理学院河南郑州450001

乡村振兴面临着满足人民日益增长的美好生活需要的新挑战,同时也肩负着确保不发生规模性返贫的底线任务。乡村振兴战略实施以来,脱贫群众精神风貌有了很大改观,生活水平显著提升。但目前一些农户仍面临生计脆弱、内生动力不足等问题,需... 详细信息

乡村振兴面临着满足人民日益增长的美好生活需要的新挑战,同时也肩负着确保不发生规模性返贫的底线任务。乡村振兴战略实施以来,脱贫群众精神风貌有了很大改观,生活水平显著提升。但目前一些农户仍面临生计脆弱、内生动力不足等问题,需要注重提升其自主、自助、自为的可持续生计能力。文化振兴是乡村振兴的精神内核,也是提升脱贫户可持续生计能力的有效途径。从乡村文化振兴的视角看,提升农户自身抗逆能力和发展能力,一要激发其内生发展动力,为可持续生计提供动力源泉;二要提升其科学文化素质,为可持续生计提供智力源泉;三要加大乡村文化的供给力度,为可持续性生计提供政策保障。

关键词：乡村文化振兴农户可持续生计生计能力

二维层状α⁃In_(2)Se_(3)(2H)铁电材料的各向异性光响应

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无机化学学报 2024年第10期40卷 1911-1918页

作者：吕宝华李玉珍运城学院应用化学系运城044000 运城学院工科实验实训中心运城044000

采用机械剥离法制备了2H相α⁃In_(2)Se_(3)[α⁃In_(2)Se_(3)(2H)]纳米片。通过X射线衍射(X⁃ray diffraction,XRD)、拉曼光谱、球差电镜和压电力显微镜对纳米片的结构和铁电性能进行详细表征,确定纳米片为具有特殊结构的α⁃In_(2)Se_(3)(... 详细信息

采用机械剥离法制备了2H相α⁃In_(2)Se_(3)[α⁃In_(2)Se_(3)(2H)]纳米片。通过X射线衍射(X⁃ray diffraction,XRD)、拉曼光谱、球差电镜和压电力显微镜对纳米片的结构和铁电性能进行详细表征,确定纳米片为具有特殊结构的α⁃In_(2)Se_(3)(2H)铁电材料。进一步在SiO_(2)/Si基片上成功构造了基于α⁃In_(2)Se_(3)(2H)铁电的平面四端器件,详细研究其在各个方向的光响应。结果表明,具有本征结构的α⁃In_(2)Se_(3)(2H)在相互垂直方向均没有光响应。在器件两端分别施加电压后,α⁃In_(2)Se_(3)(2H)器件在相互垂直方向均出现了明显的光响应,尤其在接近于易极化轴方向施加电压后,α⁃In_(2)Se_(3)(2H)器件出现了各向异性光响应。

关键词：二维层状α⁃In_(2)Se_(3)(2H) 机械剥离法铁电性各向异性光响应

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VS6式乙烯输送泵故障分析及改善措施

化工设计通讯 2024年第7期50卷 71-73页

作者：李玉祯山东裕龙石化有限公司山东烟台265700

立式筒袋泵(API610 VS6型式)是输送乙烯的重要设备,在实际运行中,经常出现振动异常、噪声偏大、轴承温度高、机械密封泄漏等问题,分析了立式筒袋泵出现故障的原因,综合考虑泵的使用条件及企业经济效益等因素,建议通过优化工艺操作管理... 详细信息

立式筒袋泵(API610 VS6型式)是输送乙烯的重要设备,在实际运行中,经常出现振动异常、噪声偏大、轴承温度高、机械密封泄漏等问题,分析了立式筒袋泵出现故障的原因,综合考虑泵的使用条件及企业经济效益等因素,建议通过优化工艺操作管理、加强润滑管理、增加降温措施、管路清洁化管理等方法,保障装置安全平稳运行。

关键词：乙烯 VS6立式筒袋泵故障分析改善措施

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乙烯球罐蒸发气体回收工艺研究

云南化工 2024年第5期51卷 46-50页

作者：李玉祯山东裕龙石化有限公司山东烟台265700

以某化工企业乙烯罐区为研究对象,分析了半冷冻式乙烯球罐蒸发气体损耗产生原因和排放量。在此基础上,提出了蒸发气体液化回收及气体返炼的工艺方案,进行了丙烯压缩制冷系统物料和热量衡算,解决了乙烯蒸发气体损耗问题,为其他乙烯储运... 详细信息

以某化工企业乙烯罐区为研究对象,分析了半冷冻式乙烯球罐蒸发气体损耗产生原因和排放量。在此基础上,提出了蒸发气体液化回收及气体返炼的工艺方案,进行了丙烯压缩制冷系统物料和热量衡算,解决了乙烯蒸发气体损耗问题,为其他乙烯储运系统生产管理提供参考。

关键词：乙烯球罐蒸发气体回收丙烯压缩制冷热量衡算气体返炼

基于MSPA模型和电路理论的晋西北国土空间生态修复关键区域识别

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干旱区研究 2024年第9期41卷 1593-1604页

作者：李可璇张蕾李豪张恩月李育桢宋彩云刘庚太原师范学院地理科学学院山西晋中030619 太原师范学院经济与管理学院山西晋中030619

国土空间生态修复是落实国家生态文明战略的重要举措,生态修复关键区域识别是国土空间生态修复的关键一环,是科学开展生态修复的关键和难点,对维护区域生态安全具有重要的意义,但当前我国国土空间生态修复关键区域识别相关理论研究滞后... 详细信息

国土空间生态修复是落实国家生态文明战略的重要举措,生态修复关键区域识别是国土空间生态修复的关键一环,是科学开展生态修复的关键和难点,对维护区域生态安全具有重要的意义,但当前我国国土空间生态修复关键区域识别相关理论研究滞后于实践工作。本文以晋西北为研究区,通过形态学空间分析(Morphological Spatial Analysis,MSPA)模型结合生态系统服务价值识别生态源地,采用电路理论识别与提取生态廊道,在此基础上,进行生态修复关键区域识别及时空演变规律分析,从而给出对应生态修复策略。结果显示:2000—2020年晋西北生态源地数量及面积均呈现增加的趋势,20 a间生态源地总面积从1898.43 km^(2)增长到2026.17 km^(2),空间分布呈现南部集中连片,北部零散分布的特点;生态廊道数量与长度先增加后减少,空间分布上南部保持短且密集,中部和北部由长且稀疏趋向短且密集。生态修复关键区域中,生态夹点面积总体下降,20 a间从262.89 km^(2)下降至194.34 km^(2),夹点普遍分布于生态廊道的两端邻近生态源地的区域,主要分布在偏关县、平鲁区、神池县和朔城区;生态障碍点整体呈现增加趋势,20 a间从324.61 km^(2)增长到504.72 km^(2),随后又减少到338.86 km^(2),障碍点普遍分布于生态廊道的中段,由聚集分布转变为均匀分布。研究综合生态修复关键区域时空演变特征及研究区生态本底,提出针对性生态修复策略,即加强夹点和障碍点的小流域、小区域治理,减少人为干扰,以期为区域国土空间生态修复工作提供参考。

关键词：国土空间生态修复关键区域识别时空演变晋西北

金属抗菌肽SIF_(4)对大肠杆菌拓扑异构酶活性及胞内核酸合成的影响

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食品科学 2024年第2期45卷 149-154页

作者：李玉珍肖怀秋周慧恒李篮匡燕刘淼赵谋明湖南化工职业技术学院制药与生物工程学院湖南株洲412000 华南理工大学食品科学与工程学院广东广州510000

为系统阐明金属抗菌肽SIF_(4)基于DNA拓扑异构酶靶点的非细胞质膜抑菌机理,以大肠杆菌为模式菌株,研究了金属抗菌肽SIF_(4)与基因组DNA的结合方式、对DNA拓扑异构酶I/II活性以及胞内核酸生物合成的影响机理。研究发现,金属抗菌肽SIF_(4... 详细信息

为系统阐明金属抗菌肽SIF_(4)基于DNA拓扑异构酶靶点的非细胞质膜抑菌机理,以大肠杆菌为模式菌株,研究了金属抗菌肽SIF_(4)与基因组DNA的结合方式、对DNA拓扑异构酶I/II活性以及胞内核酸生物合成的影响机理。研究发现,金属抗菌肽SIF_(4)可能以类似溴化乙锭嵌插方式与基因组DNA结合,对拓扑异构酶I有较强抑制活性,但对拓扑异构酶II影响较小,可通过影响DNA负超螺旋解链和RNA聚合酶结合催化RNA转录过程发挥抑菌活性。研究还发现,经金属抗菌肽SIF_(4)处理12 h后,大肠杆菌胞内总DNA和总RNA生物合成量均受到不同程度的抑制,且呈现良好的量-效关系,1/2最小抑菌浓度(minimal inhibitory concentration,MIC)组与对照组(0 MIC)相比,胞内DNA和RNA生物量差异不显著(P>0.05),MIC和2 MIC组与对照组相比,胞内DNA和RNA生物量差异显著(P<0.05)。实验结果可为金抗肽SIF_(4)在食源性大肠杆菌生物防控中的应用提供理论支持。

关键词：金属抗菌肽大肠杆菌拓扑异构酶核酸抗菌剂