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湖北恩施烤烟平顶期烟田碳通量日变化研究

中国烟草科学 2013年第6期34卷 43-48页

作者：王树键王瑞申国明高林孟贵星张继光霍光时鹏孙弋媛薄国栋张保全中国农业科学院烟草研究所青岛266101 中国农业科学院研究生院北京100081 湖北省烟草公司恩施州公司湖北恩施445000 云南省玉溪市特殊教育学校云南玉溪653100 浙江中烟工业有限责任公司杭州310009

为了深入了解烟田碳排放对环境的影响,利用静态箱-红外二氧化碳分析仪法对湖北恩施不同有机肥烟田碳通量的日变化特征进行了调查。结果表明,在烟草平顶期,烟田生态系统碳通量具有明显的日变化规律,最高值出现在17:30—19:30,最低值出现... 详细信息

为了深入了解烟田碳排放对环境的影响,利用静态箱-红外二氧化碳分析仪法对湖北恩施不同有机肥烟田碳通量的日变化特征进行了调查。结果表明,在烟草平顶期,烟田生态系统碳通量具有明显的日变化规律,最高值出现在17:30—19:30,最低值出现在11:30—13:30,其变化趋势与土壤湿度呈极显著负相关,菜枯、烟秆生物肥替代处理均显著促进了烟田生态系统碳排放。而烟田土壤碳通量的日变化整体波动较小,最大值出现在9:30,最小值在7:30,且其变化趋势与气温、地表温度、5 cm地温、10 cm地温均呈显著或极显著正相关。研究发现,烟田生态系统碳通量的主要贡献者是烟草的净光合作用,而不是土壤呼吸,且烟田生态系统碳通量的日变化幅度大于土壤。

关键词：烟田静态箱法碳通量日变化

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非圆齿轮系大蒜直立移栽机构优化设计与试验

农业机械学报 2020年第8期51卷 73-82页

作者：孙伟冯江蒋亦元东北农业大学工程学院哈尔滨150030 东北农业大学电气与信息学院哈尔滨150030

根据大蒜鳞芽直立朝上栽植的农艺需求,设计了一种可实现复杂栽植轨迹的二阶非圆齿轮行星轮系移栽机构。采用D-H方法建立了移栽机构的数学模型,通过对大蒜移栽轨迹与姿态进行分析,确定了直立移栽机构所需实现的优化目标;在Matlab平台下... 详细信息

根据大蒜鳞芽直立朝上栽植的农艺需求,设计了一种可实现复杂栽植轨迹的二阶非圆齿轮行星轮系移栽机构。采用D-H方法建立了移栽机构的数学模型,通过对大蒜移栽轨迹与姿态进行分析,确定了直立移栽机构所需实现的优化目标;在Matlab平台下编写了移栽机构的GUI优化设计软件,利用参数导引启发式优化算法对机构进行了多目标参数优化设计,通过人机交互优选出一组非劣解;采用自上而下的参数驱动设计方法,在CATIA中完成了移栽机构的参数化建模,并对机构进行了虚拟样机验证;通过台架试验,获得各试验因素对大蒜移栽后倾斜角的影响规律;提出了针对不同工况的优化模型,在最佳参数组合方案下进行了验证。结果表明,当移栽深度为17 mm、机构转速为29.6 r/min、匹配速比为100%时,获得的蒜瓣倾斜角平均值为8.54°,当提高机构转速时,通过对参数方案进行优选可将倾斜角控制在合理的范围内,以满足大蒜直立栽植的农艺要求。

关键词：大蒜直立移栽机构非圆齿轮系多目标优化参数导引启发式优化算法

A single-nucleus transcriptomic atlas of primate liver aging uncovers the pro-senescence role of SREBP2 in hepatocytes

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Protein & Cell 2024年第2期15卷 98-120页

作者： Shanshan Yang Chengyu Liu Mengmeng Jiang Xiaoqian Liu Lingling Geng yiyuan Zhang Shuhui sun Kang Wang jian Yin Shuai Ma Si Wang Juan Carlos Izpisua Belmonte Weiqi Zhang Jing Qu Guang-Hui Liu Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China Xuanwu Hospital Capital Medical University Beijing 100053China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Aging Biomarker Consortium Beijing 100101China Altos Labs Inc.San DiegoCA 94022USA

Aging increases the risk ofliver diseases and systemic susceptibility to aging-related ***,cell type-specific changes and the underlying mechanism of liver aging in higher vertebrates remain incompletely ***,we constructed the first single-nucleus transcriptomic landscape of primate liver aging,in which we resolved cell type-specific gene expression fluctuation in hepatocytes across three liver zonations and detected aberrant cell-cell interactions between hepatocytes and niche *** in-depth dissection of this rich dataset,we identifed impaired lipid metabolism and upregulation of chronic inflammation-related genes prominently associated with declined liver functions during *** particular,hyperactivated sterol regulatory element-binding protein(SREBP)signaling was a hallmark of the aged liver,and consequently,forced activation of SREBP2 in human primary hepatocytes recapitulated in vivo aging phenotypes,manifesting as impaired detoxification and accelerated cellular *** study expands our knowledge of primate liver aging and informs the development of diagnostics and therapeutic interventions for liver aging and associated diseases.

关键词： single-nucleus RNA sequencing liver hepatocytes aging senescence SREBP2

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大学生心理状况调查1711例分析

中国性科学 2001年第3期10卷 1-12页

作者：崔以泰任晓勇孙义元郎晓涛薛福林纪宏张立成贺淑曼潘美兰陈虹陈平石嵩山天津医科大学北京医科大学北京师范大学北京工业大学贵阳医学院贵州财经学院广州教育学院汕头大学医学院

经全国教育科学规划领导小组批准,我们承担了国家'九五'规划教学重点课题之一,'社会主义市场经济条件下,大学生心理障碍的多侧面成因分析及其对策'的调研任务.其中有关大学生性心理健康状况是该课题的重要组成部分,为此我们编制了相关... 详细信息

经全国教育科学规划领导小组批准,我们承担了国家'九五'规划教学重点课题之一,'社会主义市场经济条件下,大学生心理障碍的多侧面成因分析及其对策'的调研任务.其中有关大学生性心理健康状况是该课题的重要组成部分,为此我们编制了相关的问卷,拟在全国不同类型的大学中进行2000例样本的调查.

关键词：大学生心理状况调查

Encryption/decryption and microtarget capturing by pH-driven Janus microstructures fabricated by the same femtosecond laser printing parameters

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International Journal of Extreme Manufacturing 2021年第2期3卷 89-97页

作者： Zhaoxin Lao Rui sun Dongdong Jin Zhongguo Ren Chen Xin Yachao Zhang Shaojun Jiang yiyuan Zhang Li Zhang Department of Mechanical and Automation Engineering The Chinese University of Hong KongSha TinHong KongPeople’s Republic of China CAS Key Laboratory of Mechanical Behavior and Design of Materials Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education InstitutesDepartment of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefeiAnhui 230027People’s Republic of China Chengdu Fine Optical Engineering Research Center Chengdu 610041People’s Republic of China

Several natural organism can change shape under external stimuli. These natural phenomena have inspired a vast amount of research on exploration and implementation of reconfigurable shape transformation. The Janus structure is a promising approach to achieve shape transformation based on its heterogeneous chemical or physical properties on opposite ***, the heterogeneity is generally realized by multi-step processing, different materials,and/or different processing parameters. Here, we present a simple and flexible method of producing p H-sensitive Janus microactuators from a single material, using the same laser printing parameters. These microactuators exhibit reversible structural deformations with large bending angles of ~31°and fast response(~0.2 s) by changing the p H value of the aqueous environment. Benefited from the high flexibility of the laser printing technique and the spatial arrangements, pillar heights, and bending directions of microactuators are readily controlled,enabling a variety of switchable ordered patterns and complex petal-like structures on flat surfaces and inside microchannels. Finally, we explore the potential applications of this method in information encryption/decryption and microtarget capturing.

关键词： micro actuator smart material pH hydrogel Janus structure laser printing

Telomere-dependent and telomereindependent roles of RAP1 in regulating human stem cell homeostasis

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Protein & Cell 2019年第9期10卷 649-667页

作者： Xing Zhang Zunpeng Liu Xiaoqian Liu Si Wang yiyuan Zhang Xiaojuan He Shuhui sun Shuai Ma Ng Shyh-Chang Feng Liu Qiang Wang Xiaoqun Wang Lin Liu Weiqi Zhang Moshi Song Guang-Hui Liu Jing Qu State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of Sciences Beijing 100101China Advaneed Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China National Laboratory of Biomacromolecules CAS Center for Excellenee in BiomacromoleculesInstitute of Biophysics Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Medicinal Chemical Biology Nankai UniversityTianjin 300071China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem cell and Regeneration Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative MedicineJinan UniversityGuangzhou 510632China Beijing Institute for Brain Disorders Capital Medical UniversityBeijing 100069China

RAP1 is a well-known telomere-binding protein, but its functions in human stem cells have remained unclea匚 Here we generated RAP1 -deficient human embryonic stem cells (hESCs) by using CRISPR/Cas9 technique and obtained RAP1-deficient human mesenchymal stem cells (hMSCs) and neural stem cells (hNSCs) via directed differentiation. In both hMSCs and hNSCs, RAP1 not only negatively regulated telomere length but also acted as a transcriptional regulator of RELN by tuning the methylation status of its gene promoter. RAP1 deficiency enhanced self-renewal and delayed senescence in hMSCs, but not in hNSCs, suggesting complicated lineage-specific effects of RAP1 in adult stem ***, these results demonstrate for the first time that RAP1 plays both telomeric and nontelomeric roles in regulating human stem cell homeostasis.

关键词： RAP1 stem cell telomere RELN methylation

A multi-terminal ion-controlled transistor with multifunctionality and wide temporal dynamics for reservoir computing

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Nano Research 2024年第5期17卷 4444-4453页

作者： Kekang Liu Jie Li Fangzhou Li yiyuan Lin Hongrui Liu Linzi Liang Zhiyuan Luo Wei Liu Mengye Wang Feichi Zhou Yanghui Liu School of Materials Sun Yat-Sen UniversityShenzhen 518107China School of Microelectronics Southern University of Science and TechnologyShenzhen 518055China School of Software East China Jiaotong UniversityNanchang 330013China

Reservoir computing(RC)is an energy-efficient computational framework with low training cost and high efficiency in processing spatiotemporal *** state-of-the-art fully memristor-based hardware RC system suffers from bottlenecks in the computation efficiencies and accuracy due to the limited temporal tunability in the volatile memristor for the reservoir layer and the nonlinearity in the nonvolatile memristor for the readout ***,integrating different types of memristors brings fabrication and integration *** overcome the challenges,a multifunctional multi-terminal electrolyte-gated transistor(MTEGT)that combines both electrostatic and electrochemical doping mechanisms is proposed in this work,integrating both widely tunable volatile dynamics with high temporal tunable range of 10^(2) and nonvolatile memory properties with high long-term potentiation/long-term depression(LTP/LTD)linearity into a single *** ion-controlled physical RC system fully implemented with only one type of MTEGT is constructed for image recognition using the volatile dynamics for the reservoir and nonvolatility for the readout ***,an ultralow normalized mean square error of 0.002 is achieved in a time series prediction *** is believed that the MTEGT would underlie next-generation neuromorphic computing systems with low hardware costs and high computational performance.

关键词： reservoir computing multi-terminal electrolyte-gated transistor ionic controlling rich dynamics nonlinear dynamical prediction

割前摘脱收获机立式离心分离复脱清选装置优化

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农业机械学报 2018年第7期49卷 73-81页

作者：孙伟那明君冯江蒋亦元东北农业大学工程学院哈尔滨150030 东北农业大学电气与信息学院哈尔滨150030

针对水稻割前摘脱脱出物草谷比低和处理量大的特点,为提高谷物脱出物的处理能力,设计了一种可循环喂入的立式离心分离复脱清选装置并对其进行了响应面优化试验。以喂入速度和螺旋输送器转速为影响因素,以分离率、复脱率和破碎率为试验指... 详细信息

针对水稻割前摘脱脱出物草谷比低和处理量大的特点,为提高谷物脱出物的处理能力,设计了一种可循环喂入的立式离心分离复脱清选装置并对其进行了响应面优化试验。以喂入速度和螺旋输送器转速为影响因素,以分离率、复脱率和破碎率为试验指标,通过二次正交旋转中心组合试验得到了其性能指标和工作参数的响应曲面模型。利用Design-Expert软件分析各参数对性能指标的交互作用可知,输送器转速对分离率、复脱率和破碎率的影响较大,而喂入速度则较小。通过多目标优化,得到最佳工作参数:输送器转速541.4 r/min、喂入量1.226 kg/s;在该参数组合下的期望结果:分离率为90.4%、复脱率为66.1%、破碎率为0.77%;在该参数组合下的验证性试验结果:分离率为89.4%、复脱率为65.2%、破碎率为0.83%。结果表明立式离心分离复脱清选装置处理效率高,谷物损伤小,能够适应对割前摘脱脱出物的处理要求。

关键词：收获机割前摘脱复脱分离清选响应面法

Enhanced therapeutic effects of apoptotic cell-conditioned mesenchymal stem cells in lupus-prone MRL/lpr mice

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Rheumatology & Autoimmunity 2024年第2期4卷 90-98页

作者： Zhuoya Zhang yiyuan Cui Saisai Huang Weilin Liu Chen Chen Xuebing Feng Dandan Wang Lingyun sun Department of Rheumatology and Immunology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsuChina Department of Rheumatology and Immunology Nanjing Drum Tower HospitalNanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjingJiangsuChina Department of Nutrition Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsuChina

Background::Apoptotic cell-conditioned mesenchymal stem cells (AC-MSCs) exhibit stronger T cell suppressive ability via cyclooxygenase 2 (COX2)/prostaglandin E2 (PGE2);however, whether AC-MSCs exhibit enhanced therapeutic effects on systemic lupus erythematosus (SLE) remains unknown. Methods: Splenocytes from MRL/MPJ-Fas lpr (MRL /lpr) mice were cocultured with AC-MSCs, and the proportion of plasma cells was determined by flow cytometry. MSCs, AC-MSCs, COX2 knockdown MSCs, and COX2 knockdown AC-MSCs were infused into MRL/ lpr mice ( n = 10/group). Survival rates and lupus symptoms, including proteinuria, kidney injury, renal immune complex deposition, and autoantibody production, were assessed. Additionally, the number of plasma cells and serum levels of inflammatory cytokines were measured. Results::The AC-MSCs significantly inhibited plasma cells via PGE2 after 24 h coculture in vitro, whereas MSCs did not. In the MRL /lpr mice, AC-MSC treatment led to a significantly higher survival rate than phosphate-buffered saline (PBS) treatment (90% vs. 50%, p < 0.05). Moreover, AC-MSC infusion decreased urine protein levels as early as 1 week after administration (0.89 ± 0.55 mg/mL vs. 1.59 ± 0.60 mg/mL, p < 0.05, compared with PBS treatment). Administration of both MSCs and AC-MSCs reduced renal immunoglobulin G and complement C3 deposition, whereas COX2 knockdown MSCs and COX2 knockdown AC-MSCs did not. Serum anti-dsDNA antibody levels in AC-MSC-treated mice significantly decreased (0.40 ± 0.25 vs. 0.99 ± 0.58, p < 0.05), compared with PBS treatment, as well as the number of plasma cells in both the spleen ([2.14 ± 1.05] × 10^(6) vs. [8.02 ± 4.01] × 10^(6), p < 0.01) and renal-draining lymph nodes ([0.78 ± 0.68] × 10^(6) vs. [2.49 ± 1.45] × 10^(6), p < 0.05). Additionally, AC-MSCs inhibited the production of inflammatory cytokines, including interleukin-21, tumor necrosis factor-alpha, and monocyte chemoattractant protein-1. Conclusions::AC-MSCs enhanced the therapeutic

关键词： apoptotic cells mesenchymal stem cells precondition prostaglandin E2 systemic lupus erythematosus