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Acta Mathematica Scientia 2024年第1期44卷 247-274页

作者：郭真华张学耀 School of Mathematics and CNS Northwest UniversityXi’an710127China School of Mathematics and Information Science Guangxi UniversityNanning530004China

In this paper,we study the one-dimensional motion of viscous gas near a vacuum,with the gas connecting to a vacuum state with a jump in *** interface behavior,the pointwise decay rates of the density function and the expanding rates of the interface are obtained with the viscosity coefficientμ(ρ)=ρ^(α)for any 0α1;this includes the timeweighted boundedness from below and *** smoothness of the solution is ***,we construct a class of self-similar classical solutions which exhibit some interesting properties,such as optimal *** present paper extends the results in[Luo T,Xin Z P,Yang *** J Math Anal,2000,31(6):1175-1191]to the jump boundary conditions case with density-dependent viscosity.

关键词： decay rates interface Navier-Stokes equations vacuum

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寒地桑叶多糖化学组成及其生物活性分析

食品科学 2024年第15期45卷 59-66页

作者：韩晓云郑丹张雪瑶杜宝昌孙庆申黑龙江大学生命科学学院农业微生物技术教育部工程研究中心黑龙江省寒区植物基因与生物发酵重点实验室黑龙江省普通高校分子生物学重点实验室黑龙江省普通高校微生物重点实验室黑龙江哈尔滨150080 甘南林场黑龙江齐齐哈尔162100

为探究龙桑一号(Morus abla *** 1)桑叶多糖(mulberry leaf polysaccharide,MLP)的结构及功能性质,采用水提法提取其MLP,并对该多糖的结构性质以及体外降糖、抗氧化和免疫活性进行分析。结果表明:提取MLP得率为(16.16±0.30)mg/g,其中...

为探究龙桑一号(Morus abla *** 1)桑叶多糖(mulberry leaf polysaccharide,MLP)的结构及功能性质,采用水提法提取其MLP,并对该多糖的结构性质以及体外降糖、抗氧化和免疫活性进行分析。结果表明:提取MLP得率为(16.16±0.30)mg/g,其中总糖质量分数为(57.16±4.00)%,糖醛酸质量分数为(30.97±2.06)%。凝胶渗透色谱测得MLP分子质量主要分布在21.74 kDa,其单糖组成主要包括葡萄糖、鼠李糖、半乳糖、木糖、糖醛酸(包括葡萄糖醛酸、半乳糖醛酸和甘露糖醛酸)、甘露糖,物质的量比为59.17∶22.31∶10.44∶2.65∶2.28∶1.07。通过傅里叶变换红外光谱和原子力显微镜分析发现MLP是一种吡喃糖,具有分支和相互交织、螺旋聚集的特点。MLP对α-葡萄糖苷酶和α-淀粉酶抑制作用的半数有效浓度(concentration for 50%of maximal effect,EC_(50))分别为1.81 mg/mL和2.91 mg/mL,其活性相当于阿卡波糖的49.17%和37.80%;MLP清除1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基和羟自由基的EC_(50)分别为0.54、0.60 mg/mL和1.77 mg/mL,清除自由基的效果分别相当于抗坏血酸的4.77%、38.03%和19.94%;MLP可以作用于小鼠巨噬细胞RAW264.7,使其促炎因子NO、肿瘤坏死因子-α、白细胞介素-6和白细胞介素-1β的分泌量增加,增强巨噬细胞增殖作用和提高吞噬能力,从而增强免疫调节作用。本研究结果可为寒地桑叶的应用和功能评价提供实验数据。

关键词：寒地桑叶多糖结构特性免疫活性

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互联网电视中的流媒体传输优化研究

电视技术 2024年第8期48卷 118-120页

作者：许培记张学瑶张博阳江广播电视台广东阳江529500 甘肃省广播电视总台甘肃兰州730050 吉林广播电视台吉林长春130118

随着互联网电视的快速发展,流媒体技术已成为实现高清、流畅视频观看体验的关键。然而,用户对视频质量和观看体验的要求持续提高,流媒体技术的应用面临多重挑战。首先深入探讨互联网电视与流媒体技术的关系,其次详细分析流媒体技术应用...

随着互联网电视的快速发展,流媒体技术已成为实现高清、流畅视频观看体验的关键。然而,用户对视频质量和观看体验的要求持续提高,流媒体技术的应用面临多重挑战。首先深入探讨互联网电视与流媒体技术的关系,其次详细分析流媒体技术应用中的瓶颈和挑战,最后提出针对性的优化路径与策略。这些策略旨在提高视频传输的质量和效率,进而提升用户的观看体验。

关键词：互联网电视流媒体技术传输观看体验

Abundance of antibiotic resistance genes and their association with bacterial communities in activated sludge of wastewater treatment plants: Geographical distribution and network analysis

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Journal of Environmental Sciences 2019年第8期31卷 24-38页

作者： Haihan zhang Huiyan He Shengnan Chen Tinglin Huang Kuanyu Lu Zhonghui zhang Rong Wang xueyao zhang Hailong Li Key Laboratory of Northwest Resource Environment and Ecology MOE Xi'an University of Architecture and Technology Shaanxi Key Laboratory of Environmental Engineering Xi'an University of Architecture and Technology Xi'an Environmental Monitoring Center Research Institute of Applied Biology Shanxi University

Wastewater treatment plants(WWTPs) are deemed reservoirs of antibiotic resistance genes(ARGs). Bacterial phylogeny can shape the resistome in activated sludge. However, the co-occurrence and interaction of ARGs abundance and bacterial communities in different WWTPs located at continental scales are still not comprehensively understood. Here, we applied quantitative PCR and Miseq sequence approaches to unveil the changing profiles of ARGs(sul1, sul2, tet W, tet Q, tet X), int I1 gene, and bacterial communities in 18 geographically distributed WWTPs. The results showed that the average relative abundance of sul1 and sul2 genes were 2.08 × 10^(-1) and 1.32 × 10^(-1) copies/16 S rRNA copies, respectively. The abundance of tet W gene was positively correlated with the Shannon diversity index(H′), while both studied sul genes had significant positive relationship with the int I1 gene. The highest average relative abundances of sul1, sul2, tet X, and int I1 genes were found in south region and oxidation ditch system. Network analysis found that 16 bacterial genera co-occurred with tet W gene. Co-occurrence patterns were revealed distinct community interactions between aerobic/anoxic/aerobic and oxidation ditch systems. The redundancy analysis model plot of the bacterial community composition clearly demonstrated that the sludge samples were significant differences among those from the different geographical areas,and the shifts in bacterial community composition were correlated with ARGs. Together,these findings from the present study will highlight the potential risks of ARGs and bacterial populations carrying these ARGs, and enable the development of suitable technique to control the dissemination of ARGs from WWTPs into aquatic environments.

关键词： Antibiotic resistance genes Activate sludge Bacterial community Network analysis Mobile genetic elements

Combined superposition effect of hypertension and dyslipidemia on left ventricular hypertrophy

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Animal Models and Experimental Medicine 2022年第3期5卷 227-238页

作者： xueyao zhang Guangxiao Li Chuning Shi Dongyuan zhang Yingxian Sun Department of Cardiology First Hospital of China Medical UniversityShenyangChina Department of Medical Record Management First Hospital of China Medical UniversityShenyangChina NHC Key Laboratory of Human Disease Comparative Medicine Institute of Laboratory Animal SciencesChinese Academy of Medical Sciences(CAMS)Comparative Medicine CenterPeking Union Medical College(PUMC)BeijingChina

Background : Hypertension and dyslipidemia are considered reversible risk factors for cardiovascular disease. The purpose of this study was to explore the impact of traditional and nontraditional blood lipid profiles on the risk of left ventricular hypertrophy(LVH) and to explore the superposition effect of dyslipidemia combined with *** : Data on 9134 participants(53.5 ±10.3 years old) from the Northeast China Rural Cardiovascular Health Study(NCRCHS) were statistically analyzed. The blood lipid profile was measured by total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), high-density lipoprotein cholesterol(HDL-C), total glyceride(TG), and calculated nontraditional blood lipid indices including non-HDL-C, atherosclerosis index(AI), TC/HDL-C, and residual cholesterol(RC).Results : After the adjustment of age and gender, the odds ratios(ORs) of LVH in patients with hypertension, high LDL-C, high non-HDL-C, high AI, and high TC/HDL-C were 3.97(3.31– 4.76), 1.27(1.02– 1.59), 1.21(1.04– 1.39), 1.33(1.15– 1.53), and 1.42(1.22– 1.65), respectively. After full adjustment of potential confounding factors, high AI and TC/HDL-C were associated with LVH rather than traditional blood lipid *** combination of hypertension and nontraditional dyslipidemia(defined by high AI and TC/HDL-C) was associated with the highest risk of LVH, especially in participants under 45 years of age. The risk was more significant in men, 5.09-fold and 6.24-fold,respectively, compared with 3.66-fold and 4.01-fold in *** : People with dyslipidemia defined by nontraditional blood lipid indices(high AI and high TC/HDL-C) and hypertension were more likely to develop LVH.

关键词： atherosclerosis dyslipidemia hypertension l eft ventricular hypertrophy

Nitrogen addition amplified water effects on species composition shift and productivity increase

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Journal of Plant Ecology 2021年第5期14卷 816-828页

作者： Xiaolin zhang Muqier Hasi Ang Li Yulian Tan Stefani Daryanto Lixin Wang xueyao zhang Shiping Chen Jianhui Huang State Key Laboratory of Vegetation and Environmental Change Institute of Botanythe Chinese Academy of SciencesBeijing 100093China College of Grassland Science Shanxi Agricultural UniversityTdigu 030801China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Departmcnt of Earth Sciences Indiana University Purdue University IndianapolisIndianapolisIN 46202USA

Aims Water and nitrogen(N)are two key resources in dryland ecosystems,but they may have complex interactive effects on the community structure and ecosystem *** future precipitation(rainfall vs snowfall)change will impact aboveground net primary production(ANPP)is far from clear,especially when combined with increasing N *** In this study,we investigated changes in community productivity,abundance and aboveground biomass of two dominant plant functional groups(PFGs),*** rhizome grasses(PR)and perennial bunchgrasses(PB)under the impacts of increased precipitation(rainfall vs snowfall)combined with N addition in a semiarid temperate *** Findings Summer rainfall augmentation marginally increased community ANPP,whereas it significantly increased the abundance and aboveground biomass of PR,but not those of *** rainfall addition increased the fraction of PR biomass(fPR)while decreased that of PB(fPB).Spring snow addition had no effect on aboveground biomass of either compositional PFG although it marginally increased community *** addition significantly increased community ANPP with greater increase in PR under summer rainfall addition,indicating strong interactive effects on community ANPP largely by enhancing PR *** also found a nonlinear increase in the positive effect of nitrogen addition on productivity with the increased precipitation *** findings indicate an amplified impact of precipitation increase on grassland productivity under the accelerated atmospheric N deposition in the future.

关键词： aboveground net primary production community structure temperate steppe nitrogen addition snow and water addition

Thickness-dependent morphologies of Ag on n-layer MoS2 and its surface-enhanced Raman scattering

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Nano Research 2016年第6期9卷 1682-1688页

作者： Ya Deng Minjiang Chen Jian zhang Zihao Wang Wenbin Huang Yun Zhao Jean PierreNshimiyimana Xiao Hu Xiannian Chi Gu Hou ,xueyao zhang Yanjun Guo Lianfeng Sun CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology 8eijing 100190 China School of Physics Shandong University Jinan 250100 China Chinese Academy of Sciences Beijing 100049 China

The size and density of Ag nanoparticles on n-layer MoS2 exhibit thickness- dependent behavior. The size and density of these particles increased and decreased, respectively, with increasing layer number （n） of n-layer MoS2. Furthermore, the surface-enhanced Raman scattering （SERS） of Ag on this substrate was observed. The enhancement factor of this scattering varied with the thickness of MoS2. The mechanisms governing the aforementioned thickness dependences are proposed and discussed.

关键词： MoS2 nanoparticle thickness-dependent surface-enhanced Ramanscattering (SERS)

市域产教联合体下模具类专业育人模式研究与实践

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模具工业 2024年第6期50卷 77-82页

作者：潘远安孙海影王腾飞李鹏宇张雪瑶曹广祥长春汽车职业技术大学机械工程学院吉林长春130013 中国第一汽车集团有限公司工程与生产物流部吉林长春130012 中国第一汽车集团有限公司材料与轻量化研究院吉林长春130013

为积极响应国家“市域产教联合体”相关政策,通过市域内政府、本科院校、职业院校、模具企业和科研院所的“五元”产教联合体的建立,围绕经济技术开发区、产业园区、高新技术开发区展开实体化运作,将人才链集群、教育链集群、产业链集...

为积极响应国家“市域产教联合体”相关政策,通过市域内政府、本科院校、职业院校、模具企业和科研院所的“五元”产教联合体的建立,围绕经济技术开发区、产业园区、高新技术开发区展开实体化运作,将人才链集群、教育链集群、产业链集群和创新链集群“四链”深度融合,实现市场为导向共建共享管理制度的管理协同、企业文化融于校园的文化协同、多元导师团队共同培养学生的人员协同、攻坚克难解决企业难题的科研协同,积极探索高质量建设“五元四链四协同”的育人新模式。

关键词：市域产教联合体模具专业五元四链四协同育人模式

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Improving model performance in mapping cropland soil organic matter using time-series remote sensing data

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Journal of Integrative Agriculture 2024年第8期23卷 2820-2841页

作者： Xianglin zhang Jie Xue Songchao Chen Zhiqing Zhuo Zheng Wang xueyao Chen Yi Xiao Zhou Shi Institute of Applied Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Department of Land Management Zhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Institute of Digital Agriculture Zhejiang Academy of Agricultural SciencesHangzhou 310021China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China

Faced with increasing global soil degradation,spatially explicit data on cropland soil organic matter(SOM)provides crucial data for soil carbon pool accounting,cropland quality assessment and the formulation of effective management *** a spatial information prediction technique,digital soil mapping(DSM)has been widely used to spatially map soil information at different ***,the accuracy of digital SOM maps for cropland is typically lower than for other land cover types due to the inherent difficulty in precisely quantifying human *** overcome this limitation,this study systematically assessed a framework of“information extractionfeature selection-model averaging”for improving model performance in mapping cropland SOM using 462 cropland soil samples collected in Guangzhou,China in *** results showed that using the framework of dynamic information extraction,feature selection and model averaging could efficiently improve the accuracy of the final predictions(R^(2):0.48 to 0.53)without having obviously negative impacts on *** the dynamic information of the environment was an efficient way to generate covariates that are linearly and nonlinearly related to SOM,which improved the R^(2)of random forest from 0.44 to 0.48 and the R^(2)of extreme gradient boosting from 0.37to *** recursive feature selection(FRFS)is recommended when there are relatively few environmental covariates(200),whereas Boruta is recommended when there are many environmental covariates(>500).The Granger-Ramanathan model averaging approach could improve the prediction accuracy and average *** the structures of initial prediction models are similar,increasing in the number of averaging models did not have significantly positive effects on the final *** the advantages of these selected strategies over information extraction,feature selection and model averaging have a great potential for high-accuracy soil mapping

关键词： cropland soil organic matter digital soil mapping machine learning feature selection model averaging

Bidirectional relationship between type 2 diabetes mellitus and coronary artery disease:Prospective cohort study and genetic analyses

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Chinese Medical Journal 2024年第5期137卷 577-587页

作者： Wenqiang zhang Li zhang Chenghan Xiao xueyao Wu Huijie Cui Chao Yang Peijing Yan Mingshuang Tang Yutong Wang Lin Chen Yunjie Liu Yanqiu Zou Ling zhang Chunxia Yang Yuqin Yao Jiayuan Li Zhenmi Liu Xia Jiang Ben zhang Department of Epidemiology and Biostatistics Institute of Systems EpidemiologyWest China-Peking Union Medical College C.C.Chen Institute of HealthWest China School of Public Health and West China Fourth HospitalSichuan UniversityChengduSichuan 610041China Department of Maternal Child and Adolescent HealthWest China School of Public Health and West China Fourth HospitalSichuan UniversityChengduSichuan 610041China Department of Iatrical Polymer Material and Artificial Apparatus School of Polymer Science and EngineeringSichuan UniversityChengduSichuan 610041China Department of Occupational and Environmental Health West China School of Public Health and West China Fourth HospitalSichuan UniversityChengduSichuan 610041China Department of Nutrition and Food Hygiene West China School of Public Health and West China Fourth HospitalSichuan UniversityChengduSichuan 610041China Department of Clinical Neuroscience Karolinska InstitutetStockholm 17177Sweden

Background:While type 2 diabetes mellitus(T2DM)is considered a putative causal risk factor for coronary artery disease(CAD),the intrinsic link underlying T2DM and CAD is not fully *** aimed to highlight the importance of integrated care targeting both diseases by investigating the phenotypic and genetic relationships between T2DM and ***:We evaluated phenotypic associations using data from the United Kingdom Biobank(N=472,050).We investigated genetic relationships by leveraging genomic data conducted in European ancestry for T2DM,with and without adjustment for body mass index(BMI)(T2DM:N_(case)/N_(control)=74,124/824,006;T2DM adjusted for BMI[T2DM_(adj)BMI]:N_(case)/N_(control)=50,409/523,897)and for CAD(N_(case)/N_(control)=181,522/984,168).We performed additional analyses using genomic data conducted in multiancestry individuals for T2DM(N_(case)/N_(control)=180,834/1,159,055).Results:Observational analysis suggested a bidirectional relationship between T2DM and CAD(T2DM→CAD:hazard ratio[HR]=2.12,95%confidence interval[CI]:2.01–2.24;CAD→T2DM:HR=1.72,95%CI:1.63–1.81).A positive overall genetic correlation between T2DM and CAD was observed(r_(g)=0.39,P=1.43×10^(-75)),which was largely independent of BMI(T2DM_(adj)BMI–CAD:r_(g)=0.31,P=1.20×10^(–36)).This was corroborated by six local signals,among which 9p21.3 showed the strongest genetic ***-trait meta-analysis replicated 101 previously reported loci and discovered six novel pleiotropic *** randomization analysis supported a bidirectional causal relationship(T2DM→CAD:odds ratio[OR]=1.13,95%CI:1.11-1.16;CAD→T2DM:OR=1.12,95%CI:1.07-1.18),which was confirmed in multiancestry individuals(T2DM→CAD:OR=1.13,95%CI:1.10-1.16;CAD→T2DM:OR=1.08,95%CI:1.04-1.13).This bidirectional relationship was significantly mediated by systolic blood pressure and intake of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors,with mediation proportions of 54.1%(95%CI:24.9-83.4%)and 90.4%(95%CI

关键词： Type 2 diabetes mellitus Coronary artery disease Phenotypic association Genetic correlation Mendelian randomization