检索结果-南通市图书馆

Chinese Geographical Science 2024年第4期34卷 722-738页

作者： kong Yu ZHEN Feng ZHANG Shanqi SHEN Lizhen School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Provincial Engineering Research Center of Smart City Planning and Digital Governance Nanjing 210093China

The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent *** on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of *** study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering *** geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and *** located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal *** study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.

关键词： online home delivery services(OHDS) spatiotemporal accessibility neighborhoods accessibility differences Nanjing City China

Iron-Catalyzed Reductive C(aryl)—Si Cross-Coupling of Diaryl Ethers with Chlorosilanes

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Chinese Journal of Chemistry 2024年第6期42卷 578-584页

作者： Pei Liu Baowei Wu Xuefeng Cong Jie kong School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi'anShaanxi710072 China Institute of Molecular Plus Department of Chemistry and Haihe Laboratory of Sustainable Chemical TransformationsTianjin University92 Weijin RoadTianjin300072 China

The reductive cross-coupling between C(aryl)—O and Si—Cl bonds is of much importance as a valuable strategy for the construction of C(aryl)—Si bonds but has remained a great ***,we report a reductive cross-coupling of diaryl ethers and chlorosilanes via strong electrophilic C(aryl)—O and Si—Cl bonds cleavage by iron catalysis,which constitutes an efficient protocol for the synthesis of a range of functionalized *** combination of low cost FeCl2 as the precatalyst and iPrMgCl as the reductant shows high activity in the successive cleavage of unactivated C(aryl)—O bonds of diaryl ethers and strong electrophilic Si—Cl bonds of chlorosilanes,allowing their cross-coupling in a reductive *** low-valent iron species generated in situ by reduction of FeCl2 with iPrMgCl was proposed,which prefers to initially cleavage the C(aryl)—O bond of diaryl ethers with the chelation help of an o-amide auxiliary.

关键词： Cross-coupling Diaryl ethers Chlorosilanes C—O bond cleavage Iron catalyst 3d transition metals Selectivity Regioselectivity

Unsupervised social network embedding via adaptive specific mappings

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Frontiers of Computer Science 2024年第3期18卷 61-71页

作者： Youming GE Cong HUANG Yubao LIU Sen ZHANG Weiyang kong School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275China Guangdong Key Laboratory of Big Data Analysis and Processing Guangzhou 510006China

In this paper,we address the problem of unsuperised social network embedding,which aims to embed network nodes,including node attributes,into a latent low dimensional *** recent methods,the fusion mechanism of node attributes and network structure has been proposed for the problem and achieved impressive prediction ***,the non-linear property of node attributes and network structure is not efficiently fused in existing methods,which is potentially helpful in learning a better network *** this end,in this paper,we propose a novel model called ASM(Adaptive Specific Mapping)based on encoder-decoder *** encoder,we use the kernel mapping to capture the non-linear property of both node attributes and network *** particular,we adopt two feature mapping functions,namely an untrainable function for node attributes and a trainable function for network *** the mapping functions,we obtain the low dimensional feature vectors for node attributes and network structure,***,we design an attention layer to combine the learning of both feature vectors and adaptively learn the node *** encoder,we adopt the component of reconstruction for the training process of learning node attributes and network *** conducted a set of experiments on seven real-world social network *** experimental results verify the effectiveness and efficiency of our method in comparison with state-of-the-art baselines.

关键词： network embedding specific kernel mapping attention mechanism

Swelling pressure evolution characterization of strong expansive soil considering the influence of reserved expansion deformation

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Journal of Mountain Science 2024年第1期21卷 252-270页

作者： LI Tianguo kong Lingwei GUO Aiguo YAN Junbiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective structure to experience bulging failure due to excessive swelling pressure. To investigate the swelling pressure properties of expansive soil, the constant volume test was employed to study the influence of water content and reserved expansion deformation on the characteristics of swelling pressure in strong expansive soils, and also to explore the evolution mechanism of the swelling pressure. The findings demonstrate that the swelling pressure-time curve can be classified into swelling pressure-time softening and swelling pressure-time stability type. The swelling pressuretime curve of the specimen with low water content is the swelling pressure-time softening type, and the softening level will be weakened with increasing reserved expansion deformation. Besides, the maximum swelling pressure Psmax decreases with increasing water content and reserved expansion deformation, especially for expansion ratio η from 24% to 37%. The reserved deformation has little effect on reducing Psmax when it is beyond 7% of the expansion rate. The specimen with low water content has a more homogeneous structure due to the significant expansion-filling effect, and the fracture and reorganization of the aggregates in the specimens with low water content cause the swelling pressure-time softening behavior. In addition, the proposed swelling pressure-time curve prediction model has a good prediction on the test results. If necessary, a deformation space of about 7% expansion rate is recommended to be reserved in the engineering to reduce the swelling pressure except for keeping a stable water content.

关键词： Expansive soil Swelling pressure Reserved expansion deformation Water content

Recycling arsenic-containing bio-leaching residue after thermal treatment in cemented paste backfill:Structure modification,binder properties and environmental assessment

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2136-2147页

作者： Dengfeng zhao Shiyu Zhang Yingliang zhao Department of Mining Engineering Lyuliang UniversityLvliang 033000China School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 00852China

The substantial arsenic(As)content present in arsenic-containing bio-leaching residue(ABR)presents noteworthy environ-mental challenges attributable to its inherent instability and susceptibility to *** its elevated calcium sulfate content,ABR exhibits considerable promise for industrial *** study delved into the feasibility of utilizing ABR as a source of sulfates for producing super sulfated cement(SSC),offering an innovative binder for cemented paste backfill(CPB).Thermal treatment at varying temperatures of 150,350,600,and 800℃ was employed to modify ABR’s *** investigation encompassed the examination of phase transformations and alterations in the chemical composition of As within ***,the hydration characteristics of SSC utilizing ABR,with or without thermal treatment,were studied,encompassing reaction kinetics,setting time,strength development,and *** findings revealed that thermal treatment changed the calcium sulfate structure in ABR,consequently impacting the resultant sample ***,calcination at 600℃ demonstrated optimal modification effects on both early and long-term strength *** enhanced performance can be attributed to the augmented formation of reaction products and a densified ***,the thermal treatment elicited modifications in the chemical As fractions within ABR,with limited impact on the As immobilization capacity of the prepared binders.

关键词： cemented paste backfill bio-leaching residue arsenic immobilization binder hydration calcination

Progress in approved drugs from natural product resources

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Chinese Journal of Natural Medicines 2024年第3期22卷 195-211页

作者： LUO Zhongwen YIN Fucheng WANG Xiaobing kong Lingyi State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Bioactive Natural Product Research School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China

Natural products (NPs) have consistently played a pivotal role in pharmaceutical research, exerting profound impactson the treatment of human diseases. A significant proportion of approved molecular entity drugs are either directly derived from NPs orindirectly through modifications of NPs. This review presents an overview of NP drugs recently approved in China, the United States,and other countries, spanning various disease categories, including cancers, cardiovascular and cerebrovascular diseases, centralnervous system disorders, and infectious diseases. The article provides a succinct introduction to the origin, activity, development process, approval details, and mechanism of action of these NP drugs.

关键词： New drugs Natural products Structural modification

Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 483-501页

作者： Yuansheng YU Lingling LI Xiangmiao kong chengyuan LI Zhen GUO Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Hainan Institute Zhejiang UniversitySanya572000China Ninghai Highway and Transportation Management Center Ningbo315600China Ninghai Traffic Engineering Construction Management Institute Ningbo315600China

The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 24 h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability.

关键词： Construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)

Defatted Hickory Meal Hydrolysate's Impact on Memory Impairment Induced by D-Galactose in Mice

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Food Science and Human Wellness 2024年

作者： Fanping Qin Ruiling Liu Qi kong Hangjun chen Xiangjun Fang Huizhi chen Weijie Wu Haiyan Gao State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Key Laboratory of Post-Harvest Vegetable Preservation and Processing (Co-construction by Ministry and Province)， Ministry of Agriculture and Rural Affairs，Key Laboratory of Light Industry Fruit and Vegetable Preservation and Processing， Institute of Food Science， Zhejiang Academy of Agricultural Sciences

Defatted hickory meal (DHM)， a by-product of hickory oil production， is a protein source rich in essential amino acids. In this study， the functional properties of DHM hydrolysate (DHMH) were assessed using in vitro and in vivo assays in context to its antioxidant and memory-enhancing effects. To induce memory impairment， D-galactose (D-gal) was administered to mice at a dose of 120 mg/kg body weight per day， and DHMH was orally administered at doses of 300， 600， and 1000 mg/kg body weight per day for 8 weeks. DHMH treatment led to improved memory performance in D-gal-induced memory-impaired mice， as observed in the Morris water maze test. Furthermore， DHMH mitigated the accumulation of amyloid beta 1-42 triggered by D-gal exposure. Notably， high-dose DHMH significantly reduced the elevation of pro-inflammatory markers， including tumor necrosis factor alpha， interleukin 1β， and interleukin 6. Additionally， DHMH prevented the decline in total superoxide dismutase activity， glutathione peroxidase activity， and glutathione levels， while reducing malondialdehyde content in D-gal-induced mice， indicative of its antioxidant properties. Moreover， DHMH treatment effectively prevented histological alterations in neurons within the hippocampal CA1 area induced by D-gal. Collectively， our findings suggest that DHMH may counteract memory dysfunctions resulting from oxidative stress injury in the brain， positioning it as a potential candidate for use as a functional food.

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乌鲁木齐东道海子剖面的硅藻记录与环境演变

干旱区地理 2005年第1期28卷 81-87页

作者：李树峰阎顺孔昭宸倪健中国科学院新疆生态与地理研究所乌鲁木齐830011 中国科学院植物研究所植被数量生态学重点实验室北京100029

通过分析乌鲁木齐河尾闾湖泊东道海子剖面的硅藻记录,结合孢粉、磁化率、烧失量和粒度分析资料,以C测年数据为基础,讨论了天山北麓古尔班通古特沙漠南部边缘的环境演变。研究认为:东道海子地区在490014a BP～3120a BP这一时段气候较稳定... 详细信息

通过分析乌鲁木齐河尾闾湖泊东道海子剖面的硅藻记录,结合孢粉、磁化率、烧失量和粒度分析资料,以C测年数据为基础,讨论了天山北麓古尔班通古特沙漠南部边缘的环境演变。研究认为:东道海子地区在490014a BP～3120a BP这一时段气候较稳定,3120a BP以来,有几次波动;湖泊的高湖面期与气候的冷期对应,湖泊的盐碱度较低,硅藻以及水生、沼生植物生长较繁盛;湖泊的中湖面期与气候的暖期对应,湖泊的盐碱度较高,硅藻以及水生、沼生植物生长较稀少。

关键词：环境演变剖面硅藻湖泊测年暖期冷期盐碱气候植物生长

Rare loss-of-function variants in FLNB cause non-syndromic orofacial clefts

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Journal of Genetics and Genomics 2024年第2期51卷 222-229页

作者： Wenbin Huang Shiying Zhang Jiuxiang Lin Yi Ding Nan Jiang Jieni Zhang Huaxiang zhao Feng chen Department of Orthodontics Peking University School and Hospital of StomatologyBeijing100081China Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of StomatologyXi’an Jiaotong UniversityXi’anShaanxi710004China Guangdong Provincial High-level Clinical Key Specialty Guangdong Province Engineering Research Center of Oral Disease Diagnosis and TreatmentDepartment of OrthodonticsStomatological CenterPeking University Shenzhen HospitalShenzhen Peking University-The Hong Kong University of Science and Technology Medical CenterShenzhenGuangdong 518036China Department of Physiology and Pathophysiology School of Basic Medical SciencesXi'an Jiaotong UniversityXi'anShaanxi710049China National Center for Stomatology National Clinical Research Center for Oral DiseasesNational Engineering Laboratory for Digital and Material Technology of StomatologyBeijing Key Laboratory for Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijing100101China Central Laboratory Peking University School and Hospital of StomatologyBeijing100081China

Orofacial clefts (OFCs) are the most common congenital craniofacial disorders, of which the etiology is closely related to rare coding variants. Filamin B (FLNB) is an actin-binding protein implicated in bone formation. FLNB mutations have been identified in several types of syndromic OFCs and previous studies suggest a role of FLNB in the onset of non-syndromic OFCs (NSOFCs). Here, we report two rare heterozygous variants (p.P441T and p.G565R) in FLNB in two unrelated hereditary families with NSOFCs. Bioinformatics analysis suggests that both variants may disrupt the function of FLNB. In mammalian cells, p.P441T and p.G565R variants are less potent to induce cell stretches than wild type FLNB, suggesting that they are loss-of-function mutations. Immunohistochemistry analysis demonstrates that FLNB is abundantly expressed during palatal development. Importantly, Flnb^(−/−) embryos display cleft palates and previously defined skeletal defects. Taken together, our findings reveal that FLNB is required for development of palates in mice and FLNB is a bona fide causal gene for NSOFCs in humans.

关键词： Or ofacial clefts FLNB Loss-of-function mutati on Cleft palate Filamin B Actin flannent Knockout mouse