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Journal of Materials Science & Technology 2024年第1期168卷 124-130页

作者： Yiqing wei Jiaqi Liu Zien Cheng Pengfei Jiang Zizhen Zhou Bin Zhang Guoyu Wang Guang Han Xu Lu xiaoyuan Zhou Center of Quantum Materials and Devices College of PhysicsChongqing UniversityChongqing 401331China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China Analytical and Testing Center Chongqing UniversityChongqing 401331China

Tetrahedrite,an Earth-abundant natural mineral,has attracted extensive research interest because of its excellent thermoelectric performance.Herein,tetrahedrite samples comprising Cu-poor Cu_(12)Sb_(4)S_(13)and Cu-rich Cu_(14)Sb_(4)S_(13)phases have been synthesized using a colloidal method,in which the ratio of two phases is manipulated by controlling the synthesis temperature to improve the thermoelectric perfor-mance.It is found that an ultralow total thermal conductivity of∼0.3 W m^(−1)K^(−1)at 723 K is realized in the sample with a Cu-rich phase fraction of∼50%,which can be attributed to maximized phonon scattering by phase boundaries.As a result,combined with a decent power factor,this sample obtains an optimal zT of 1.15,which is about 85%higher than that of the sample with a Cu-rich phase fraction of∼64%and comparable to zT values of other eco-friendly,abundant Cu-based thermoelectric materials.This work demonstrates an effective synthesis-temperature-dependent phase composition manipulation strategy toward enhanced thermoelectric performance in tetrahedrites.

关键词： Tetrahedrite Thermoelectric Colloidal method Phase manipulation Thermal conductivity

Influence of modulation period for β-Cu2+xSe/SiC nano-multilayer films on their thermoelectric properties

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Progress in Natural Science:Materials International 2022年第5期32卷 586-593页

作者： Guihong Song Yu Chen Hao Du xiaoyuan wei Guipeng Li Yusheng Wu Junhua You Fang Hu School of Materials Science and Technology Shenyang University of Technology Guangzhou Maritime University Institute of Corrosion Science and Technology

In this study, β-Cu2+xSe/SiC nano-multilayer films with different modulation period were successfully deposited on SiO2/Si substrates by sputtering alternately using Cu–Se and SiC targets. The deposited films were observed on both surface and cross-section, and the thermoelectric properties were studied. The results show that both carrier concentration and mobility at room temperature decreased with the reducing modulation period for the nanomultilayer films. The conductivity slightly decreased and Seebeck coefficient greatly increased with the reducing modulation period. As a result of competition, the power factor of the nano multilayer films increased with the reducing modulation period because the positive effect of the Seebeck coefficient exceeded the negative effect of the conductivity. In the case of β-Cu2+xxSe/SiC nano multilayer film with the smallest modulation periods(210 nm), the power factor reached 0.39 mWm-1K-2and 0.59 mWm-1K-2at room temperature and 325°C,respectively. The enhanced power factor for nano multilayer films is attributed to the scattering process at theβ-Cu2+xSe/SiC layer interface, which reduces the carrier concentration and the mobility. It is concluded that the thermoelectric properties of β-Cu2+xSe films can be effectively improved by designing nano multilayer structure.

关键词： Thermoelectric materials β-Cu 2-x Se/SiC multilayer Films Seebeck coefficient Layer interface scattering Modulation period

Donor age and body weight determine the effects of fecal microbiota transplantation on growth performance,and fecal microbiota development in recipient pigs

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Journal of Animal Science and Biotechnology 2022年第5期13卷 1483-1498页

作者： Xiaofan Wang Tsungcheng Tsai Bin Zuo xiaoyuan wei Feilong Deng Ying Li Charles V.Maxwell Hua Yang Yingping Xiao Jiangchao Zhao Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleARUSA Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding College of Life Science and EngineeringFoshan UniversityFoshan 528225China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhouChina

Background:The application of fecal microbiota transplantation(FMT)to improve swine growth performance has been sporadically studied.Most of these studies used a single microbiota source and thus the effect of donor characteristics on recipient pigs’fecal microbiota development and growth performance is largely unknown.Results:In this study,we collected feces from six donors with heavy(H)or light(L)body weight and different ages(d 42,nursery;d 96,growing;and d 170,finisher)to evaluate their effects on the growth performance and fecal microbiota development of recipient pigs.Generally,recipients that received two doses of FMT from nursery and finisher stages donor at weaning(21±2 days of age)inherited the donor’s growth pattern,while the pigs gavaged with grower stage material exerted a numerically greater weight gain than the control pigs regardless of donor BW.FMT from heavier donors(NH,GH,and FH)led to the recipients to have numerically increased growth compared to their lighter counterparts(NL,GL,and FL,respectively)throughout the growing and most finishing stages.This benefit could be attributed to the enrichment of ASV25 Faecalibacterium,ASV61 Faecalibacterium,ASV438 Coriobacteriaceae_unclassified,ASV144 Bulleidia,and ASV129 Oribacterium and decrease of ASV13 Escherichia during nursery stage.Fecal microbiota transplantation from growing and finishing donors influenced the microbial community significantly in recipient pigs during the nursery stage.FMT of older donors’gut microbiota expedited recipients’microbiota maturity on d 35 and 49,indicated by increased estimated microbiota ages.The ageassociated bacterial taxa included ASV206 Ruminococcaceae,ASV211 Butyrivibrio,ASV416 Bacteroides,ASV2 Streptococcus,and ASV291 Veillonellaceae.The body weight differences between GL and GH pigs on d 104 were associated with the increased synthesis of the essential amino acid,lysine and methionine,mixed acid fermentation,expedited glycolysis,and sucrose/galactose degradation.Conclusions:Overall,our study provided insights

关键词： Colonization FMT Growth performance Swine gut microbiome

自适应注意力LSTM-ResNet下的滚动轴承故障诊断

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制造技术与机床 2024年第6期 74-81页

作者：姜健魏小源绵阳职业技术学院四川绵阳621000 兰州理工大学电气工程与信息工程学院甘肃兰州730050 甘肃省工业过程先进控制重点实验室甘肃兰州730050

滚动轴承信号具有复杂性和非线性的特点,对特征提取和故障分类带来挑战。为解决上述问题,文章提出一种自适应注意力LSTM-Resnet(long short-term memory residual network)下的滚动轴承故障诊断方法。首先设计双向LSTM组特征提取模型,... 详细信息

滚动轴承信号具有复杂性和非线性的特点,对特征提取和故障分类带来挑战。为解决上述问题,文章提出一种自适应注意力LSTM-Resnet(long short-term memory residual network)下的滚动轴承故障诊断方法。首先设计双向LSTM组特征提取模型,获取复杂运行条件下的滚动轴承特征;然后,提出自适应注意力LSTM-ResNet完成特征学习,并自适应调整模型中关键特征的权重;最后,采用全局平均池化(global average pooling,GAP)方法结合Softmax模型缓解模型过拟合并完成故障分类。在数据集中完成滚动轴承故障分类,实验结果表明:文章方法的滚动轴承故障诊断准确率相对于SVD-ResNet方法和宽卷积模型更高,并且能在标记样本数量较少和噪声环境下均达到较高的检测准确率,具有更高的准确性和更强的鲁棒性。

关键词：机械设备故障诊断 LSTM 权重 Softmax GAP

The vaginal and fecal microbiomes are related to pregnancy status in beef heifers

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Journal of Animal Science and Biotechnology 2020年第1期11卷 58-70页

作者： Feilong Deng Maryanna McClure Rick Rorie Xiaofan Wang Jianmin Chai xiaoyuan wei Songjia Lai Jiangchao Zhao Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleARUSA Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengduChina Special Key Laboratory of Microbial Resources and Drug Development Research Center for Medicine and BiologyZunyi Medical UniversityZunyiChina.

Background:The greatest impact on profitability of a commercial beef operation is reproduction.However,in beef heifers,little is known about the vaginal and fecal microbiota with respect to their relationship with fertility.To this end,we followed heifers through gestation to examine the dynamics of vaginal and fecal microbial composition throughout pregnancy.Results:Heifers were exposed to an estrus synchronization protocol,observed over a 12-day period,artificially inseminated 12 h to 18 h after observed estrus,and subsequently exposed to bulls for a 50-day breeding season.Vaginal samples were taken at pre-breeding(n=72),during the first(n=72),and second trimester(n=72)for all individuals,and third trimester for individuals with confirmed pregnancies(n=56).Fecal samples were taken at prebreeding(n=32)and during the first trimester(n=32),including bred and open individuals.Next generation sequencing of the V4 region of the 16 S rRNA gene via the Illumina Mi Seq platform was applied to all samples.Shannon indices and the number of observed bacterial features were the same in fecal samples.However,significant differences in vaginal microbiome diversity between gestation stages were observed.No differences in beta-diversity were detected in vaginal or fecal samples regarding pregnancy status,but such differences were seen with fecal microbiome over time.Random Forest was developed to identify predictors of pregnancy status in vaginal(e.g.,Histophilus,Clostridiaceae,Campylobacter)and fecal(e.g.,Bacteroidales,Dorea)samples.Conclusions:Our study shows that bovine vaginal and fecal microbiome could be used as biomarkers of bovine reproduction.Further experiments are needed to validate these biomarkers and to examine their roles in a female’s ability to establish pregnancy.

关键词： Beef cattle Pregnancy Random forest Reproduction Vaginal microbiome

环鄱阳湖城市群土地利用功能转型及其驱动机制

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农业工程学报 2024年第7期40卷 298-308页

作者：丁孝媛叶长盛胡海平肖蔚刘金花东华理工大学地球科学学院南昌330013

快速城镇化背景下,推进土地利用高质量转型是实现区域可持续协同发展的重要路径。该研究基于土地利用主导功能,运用综合指数法、耦合协调度模型和时空地理加权回归模型(geographically and temporally weighted regression,GTWR)等方法... 详细信息

快速城镇化背景下,推进土地利用高质量转型是实现区域可持续协同发展的重要路径。该研究基于土地利用主导功能,运用综合指数法、耦合协调度模型和时空地理加权回归模型(geographically and temporally weighted regression,GTWR)等方法,分析了环鄱阳湖城市群土地利用功能转型的时空演变特征、耦合协调水平及其驱动机制。结果表明:1)2000—2020年,环鄱阳湖城市群土地利用功能指数从0.20上升到0.55,持续优化提升,但总体上处于中低水平,土地利用功能水平表现为阶段性的变化特征;土地利用功能指数逐渐呈现出中西高、东部低的空间格局。2)生产-生活-生态功能及生产-生活功能的协调度指数持续上升,其余耦合度及协调度指数均呈波动发展的趋势,耦合协调度指数呈现中部和西南部高、东北和西北部低的空间分布格局;以低质量转型为主,平均占比约为50%,功能转型质量有所提升,中西部区县的土地利用功能转型质量要明显优于北部和东部区县。3)不同影响因子的驱动作用存在显著的空间差异。人口密度和城镇化水平的正向驱动作用持续增强,二三产业占比的负向驱动作用增强,人均GDP、人均固定资产投资和人均粮食产量的影响力趋于减弱。应根据各区县土地利用功能的转型阶段,实行差别化的发展政策,补齐区县发展短板,提升功能系统间的耦合协调度。研究结果可为提高区域用地效率,促进土地利用多功能协同发展提供参考和决策依据。

关键词：土地利用功能转型时空格局耦合协调关系驱动机制环鄱阳湖城市群

Small molecule compound induces chromatin de-condensation and facilitates induced pluripotent stern cell generation

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Journal of Molecular Cell Biology 2014年第5期8卷 409-420页

作者： xiaoyuan wei Yueting Chen Yongyu Xu YangZhan Ru Zhang Min Wang Qiuhong Hua Haifeng Gu Fajun Nan Xin Xie Shanghai Key Laboratory of Signaling and Disease Research Laboratory of Receptor-based Bio-medicine School of Life Sciences and Technology Tongji University Shanghai 200092 China CAS Key Laboratory of Receptor Research the National Center for Drug Screening Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China State Key Laboratory of Drug Research the National Center for Drug Screening Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China

The revolutionary induced pluripotent stem cell (iPSC) technology provides a new means for cell replacement therapies and drug screening. Small molecule compounds have been found extremely useful to improve the generation of iPSCs and understand the reprogramming mechanism. Here we report the identification of a novel chemical, CYT296, which improves OSKM-mediated induction of iPSCs for >10 folds and enables efficient reprogramming with only Oct4 in combination with other small molecules. The derived iPSCs are genuinely pluripotent and support the development of two ‘All-iPSC’ mice by tetraploid complementation. CYT296 profoundly impacts heterochromatin formation without affecting cell viability. MEFs treated with CYT296 exhibit de-condensed chromatin structure with markedly reduced loci containing heterochromatin protein 1α (HP1α) and H3K9me3, which is very similar to the chromatin configuration in embryonic stem cells (ESCs). Given that an open chromatin structure serves as a hallmark of pluripotency and has to be acquired to fulfill reprogramming, we propose that CYT296 might facilitate this process by disrupting condensed chromatin, thereby creating a more favorable environment for reprogramming. In agreement of this idea, shRNA targeting HP1α also promotes the generation of iPSCs. Thus current findings not only provide a novel chemical for efficient iPSC induction, but also suggest a new approach to regulate somatic cell reprogramming by targeting chromatin de-condensation with small molecules.

关键词：小分子化合物多能干细胞异染色质诱导凝聚染色质结构船尾凯尔特人

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基于模型的四足机器人步态转换控制研究

农业机械学报 2024年第3期55卷 431-440,451页

作者：陈久朋李春磊伞红军康伟巴光玉杨晓园昆明理工大学机电工程学院昆明650500 昆明市农业机械技术推广站昆明650500

为了解决基于模型的控制方法在四足机器人步态转换过程中稳定控制问题,本文在仿生学和机构学基础上设计了一款四足机器人样机平台,并推导了机器人单腿运动学模型。在足端可达工作空间内规划了机器人抬腿高度和迈步步长,利用理想的复合... 详细信息

为了解决基于模型的控制方法在四足机器人步态转换过程中稳定控制问题,本文在仿生学和机构学基础上设计了一款四足机器人样机平台,并推导了机器人单腿运动学模型。在足端可达工作空间内规划了机器人抬腿高度和迈步步长,利用理想的复合摆线轨迹,通过合理控制步态周期,提出了一种过渡段变周期控制方法,实现了步态转换前后定速度控制和变步长控制,保证了步态转换前后速度不变或可变。为了验证所提算法的正确性和稳定性,分别开展了单腿足端轨迹实验和整机步态转换实验。在完成整机运动控制的基础上,对比了基于模型的控制方式和基于中枢模式发生器的控制方式在四足机器人步态转换过程的应用。仿真和实验结果表明,在基于模型的控制算法下,四足机器人可以实现步态的平滑转换,且速度能伴随步长和周期的变化实现调节,满足了不同速度下的行走要求,为四足机器的运动控制提供了参考。

关键词：四足机器人步态转换稳定性

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Self-Assembled Nanomicelles of Affibody-Drug Conjugate with Excellent Therapeutic Property to Cure Ovary and Breast Cancers

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Nano-Micro Letters 2022年第2期14卷 190-205页

作者： Xuelin Xia xiaoyuan Yang wei Huang Xiaoxia Xia Deyue Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Affibody molecules are small nonimmunoglobulin affinity proteins,which can precisely target to some cancer cells with specific overexpressed molecular signatures.However,the relatively short in vivo half-life of them seriously limited their application in drug targeted delivery for cancer therapy.Here an amphiphilic affibody-drug conjugate is self-assembled into nanomicelles to prolong circulation time for targeted cancer therapy.As an example of the concept,the nanoagent was prepared through molecular self-assembly of the amphiphilic conjugate of Z_(HHR2:342)-Cys with auristatin E derivate,where the affibody used is capable of binding to the human epidermal growth factor receptor 2(HER2).Such a nanodrug not only increased the blood circulation time,but also enhanced the tumor targeting capacity(abundant affibody arms on the nanoagent surface) and the drug accumulation in tumor.As a result,this affibody-based nanoagent showed excellent antitumor activity in vivo to HER2-positive ovary and breast tumor models,which nearly eradicated both small solid tumors(about 100 mm^(3)) and large established tumors(exceed 500 mm^(3)).The relative tumor proliferation inhibition ratio reaches 99.8% for both models.

关键词： Molecular self-assembly Affibody-drug conjugate Nanoagent Targeted cancer therapy

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2023年肝脏疾病研究进展

中华肝脏病杂志 2024年第1期32卷 3-15页

作者：窦晓光徐小元南月敏魏来韩涛茅益民韩英任红贾继东庄辉中国医科大学附属盛京医院感染科沈阳110022 北京大学第一医院北京100034 河北医科大学第三医院中西医结合肝病科石家庄050051 清华大学附属北京清华长庚医院肝胆胰中心北京102218 南开大学人民医院天津300121 上海交通大学医学院附属仁济医院上海200001 空军军医大学第一附属医院消化内科西安710032 重庆医科大学附属第二医院感染病科重庆401336 首都医科大学附属北京友谊医院肝病中心北京100050 北京大学医学部基础医学院病原生物学系和感染病研究中心北京100191

2023年在肝脏疾病各研究领域都有重大进展,现就病毒性肝炎、肝纤维化和肝硬化、肝细胞癌(hepatocellular carcinoma,HCC)、肝衰竭和人工肝、代谢性(脂肪性)肝病、药物性肝损伤(drug-induced liver injury,DILI)及自身免疫性肝病(autoimm... 详细信息

2023年在肝脏疾病各研究领域都有重大进展,现就病毒性肝炎、肝纤维化和肝硬化、肝细胞癌(hepatocellular carcinoma,HCC)、肝衰竭和人工肝、代谢性(脂肪性)肝病、药物性肝损伤(drug-induced liver injury,DILI)及自身免疫性肝病(autoimmune liver disease,ALD)等领域研究进展进行简要介绍。

关键词：病毒性肝炎肝纤维化肝硬化肝细胞癌脂肪肝肝功能衰竭药物性肝损伤肝移植自身免疫性肝病