不同纬度兴安落叶松林土壤碳氮含量特征及影响机制

土壤碳和氮是生态系统物质循环的重要组成部分。在全球变化背景下,对森林生态系统土壤碳和氮含量的变化规律和机制的研究是当今生态学的研究热点。本文沿不同纬度梯度的天然兴安落叶松林进行了野外土壤采样调查和分析,以期阐明兴安落叶松林中土壤碳氮含量的分布规律及机制。结果表明,兴安落叶松林土壤有机碳含量和碳氮比均随纬度的降低而增加,土壤总氮含量则随纬度的降低而先升高后降低,深层土比浅层土土壤碳、氮含量低。土壤碳与氮均受到气候因素和土壤因素的影响,且响应机制大致相同。年均温和年降水与土壤碳、氮含量呈显著正相关关系;海拔与土壤碳、氮含量呈显著负相关关系。土壤容重、砂土含量、pH与土壤有机碳和土壤总氮含量呈正相关关系;土壤黏土含量和壤土含量与其呈负相关关系。该研究为揭示森林生态系统中土壤碳、氮含量响应气候变化的规律及机制提供科学依据

Multiscale biomechanics and mechanotransduction from liver fibrosis to cancer

A growing body of multiscale biomechanical studies has been proposed to highlight the mechanical cues in the development of hepatic fibrosis and cancer. At the cellular level, changes in mechanical microen-vironment induce phenotypic and functional alterations of hepatic cells, initiating a positive feedback loop that promotes liver fibrogenesis and hepatocarcinogenesis. Tumor mechanical microenvironment of hepatocellular carcinoma facilitates tumor cell growth and metastasis, and hinders the drug delivery and immunotherapy. At the molecular level, mechanical forces are sensed and transmitted into hepatic cells via allosteric activation of mechanoreceptors on the cell membrane, leading to the activation of var-ious mechanotransduction pathways including integrin and YAP signaling and then regulating cell func-tion. Thus, the application of mechanomedicine concept in the treatment of liver diseases is promising for rational design and cell-specific delivery of therapeutic drugs. This review mainly discusses the correla-tion between biomechanical cues and liver diseases from the viewpoint of mechanobiology.(c) 2022 Elsevier B.V. All rights reserved

Biomechanics in liver regeneration after partial hepatectomy

The liver is a complicated organ within the body that performs wide-ranging and vital functions and also has a unique regenerative capacity after hepatic tissue injury and cell loss. Liver regeneration from acute injury is always beneficial and has been extensively studied. Experimental models including partial hepatectomy (PHx) reveal that extracellular and intracellular signaling pathways can help the liver recover to its equivalent size and weight prior to an injury. In this process, mechanical cues possess immediate and drastic changes in liver regeneration after PHx and also serve as main triggering factors and significant driving forces. This review summarized the biomechanics progress in liver regeneration after PHx, mainly focusing on PHx-based hemodynamics changes in liver regeneration and the decoupling of mechanical forces in hepatic sinusoids including shear stress, mechanical stretch, blood pressure, and tissue stiffness. Also discussed were the potential mechanosensors, mechanotransductive pathways, and mechanocrine responses under varied mechanical loading in vitro. Further elucidating these mechanical concepts in liver regeneration helps establish a comprehensive understanding of the biochemical factors and mechanical cues in this process. Proper adjustment of mechanical loading within the liver might preserve and restore liver functions in clinical settings, serving as an effective therapy for liver injury and diseases

脑智科学研究的最新进展与实践应用

儿童青少年的脑智提升是公共卫生健康和教育发展领域的工作核心,对于国家可持续发展具有重大战略意义。人脑影像技术可为儿童青少年脑智提升的客观监测和教育效果评估等提供科学辅助。国际上使用人脑影像技术针对儿童脑智发育规律的研究暨脑智发育影像学早在上世纪90年代初就已开展,当前已尝试将相关成果积累应用于指导教育政策制定和一线课程教学改革实践。中国科学院心理研究所的&quot;彩巢计划(CCNP)&quot;队列研究已经取得阶段性成果。</p

力学微环境调控肝血窦内皮细胞表型维持与去分化

目的肝血窦内皮细胞(liver sinusoidal endothelial cells,LSEC)是肝内一种高度分化的非实质细胞,具有独特的表型特征,在肝脏组织稳态维持中起关键作用。基质硬度、血流剪切等力学微环境的变化是多种肝脏疾病发展过程中的重要因素,但其是否可以直接调控LSEC的表型维持或去分化尚不明确。方法体外培养小鼠原代LSEC细胞

Recent Progress on Enhancing Effect of Nanosized Metals for Electrochemical CO2 Reduction

将二氧化碳通过电化学方法转化为化工原料再利用,不仅可以有效缓减温室效应,而且可以实现自然界的碳循环,对绿色化学与可持续发展意义重大. 本文简要地介绍了二氧化碳电还原的优势及其基本反应原理并综述了近年来基于纳米金属催化剂的一系列活性增强策略的研究进展. 重点探究了合金效应、界面工程、协同效应、缺陷工程以及载体效应等对纳米金属电催化还原二氧化碳性能的影响及相关反应机理. 基于以上策略,提出未来开发面向工业化应用的二氧化碳电还原催化剂面临的挑战与前景.The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER and the related reaction mechanisms are mainly reviewed. Based on the above strategy, the challenges and prospects for the future development of CO2ER catalysts for industrial applications are proposed.国家自然科学基金项目资助(21972042)通讯作者:钮东方,张新胜E-mail:[email protected];[email protected]:NIUDong-fang,ZHANGXin-shengE-mail:[email protected];[email protected]华东理工大学化工学院,化学工程联合国家重点实验室,上海 200237State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, Chin

Mechanotransduction of liver sinusoidal endothelial cells under varied mechanical stimuli

Liver sinusoidal endothelial cells (LSECs) are the gatekeeper of liver to maintain hepatic homeostasis. They are formed into the highly specialized endothelium between vascular lumen and the space of Disse and are mechanosensitive to respond varied microenvironments. Shear stress and mechanical stretch induced by blood perfusion and substrate stiffness enhancement derived from deposition of extracellular matrix (ECM) are major mechanical stimuli that surround LSECs. This review introduces how LSECs respond to the external forces in both physiological and pathological cases and what is the interplay of LSECs with other hepatic cells. Molecular mechanisms that potentiate LSECs mechanotransduction are also discussed

一种输电线路巡检机器人视觉伺服抓线控制方法

本发明公开了一种输电线路巡检机器人视觉伺服抓线控制方法.属于自动化控制领域，目的在于克服现有人工控制机器人抓线的缺点，提高输电线路巡检与作业机器人的自主化程度，扩大机器人巡检与作业的应用范围。本发明用于机器人在识别输电线路的基础上进行自主抓线。抓线控制流程如下：(1)机器人本体运动学建模；(2)建立抓线运动的手眼模型；(3)构建伺服抓线控制器框架；(4)设计视觉伺服控制器。本发明将数字图像处理技术引入到机器人自主控制，利用机器人采集的图像信息获取线路与机器人的相对位姿关系，通过视觉伺服控制器的设计，使机器人可以自主完成落线动作，为机器人在线路上开展自主化巡检与作业提供了一种智能化的技术手段

Direct mechanical exposure initiates hepatocyte proliferation

Background & Aims: Liver paracrine signaling from liver sinusoid endothelial cells to hepatocytes in response to mechanical stimuli is crucial in highly coordinated liver regeneration. Interstitial flow through the fenestrated endothelium inside the space of Disse potentiates the role of direct exposure of hepatocytes to fluid flow in the immediate regenerative responses after partial hepatectomy, but the underlying mechanisms remain unclear.Methods: Mouse liver perfusion was used to identify the effects of interstitial flow on hepatocyte proliferation ex vivo. Isolated hepatocytes were further exposed to varied shear stresses directly in vitro. Knockdown and/or inhibition of mechanosensitive proteins were used to unravel the signaling pathways responsible for cell proliferation.Results: An increased interstitial flow was visualized and hepatocytes' regenerative response was demonstrated experimentally by ex vivo perfusion of mouse livers. In vitro measurements also showed that fluid flow initiated hepatocyte pro-liferation in a duration-and amplitude-dependent manner. Mechanistically, flow enhanced 01 integrin expression and nuclear translocation of YAP (yes-associated protein), via the Hippo pathway, to stimulate hepatocytes to re-enter the cell cycle.Conclusions: Hepatocyte proliferation was initiated after direct exposure to interstitial flow ex vivo or shear stress in vitro, which provides new insights into the contributions of mechanical forces to liver regeneration. Impact and implications: By using both ex vivo liver perfusion and in vitro flow exposure tests, we identified the roles of interstitial flow in the space of Disse in stimulating hepatocytes to re-enter the cell cycle. We found an increase in shear flow -induced hepatocyte proliferation via 01 integrin-YAP mechanotransductive pathways. This serves as a useful model to potentiate hepatocyte expansion in vitro using mechanical forces.(c) 2023 The Author(s). Published by Elsevier B.V. on behalf of European Association for the Study of the Liver (EASL). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Practice of quality control circle activities in improving the accuracy of inhalants usage in patients with chronic obstructive pulmonary disease (提高慢性阻塞性肺疾病患者吸入剂规范使用率的品管圈实践)

Objective To investigate the effect of quality control circle (QCC) activities in improving the accuracy of inhalants usage in patients with chronic obstructive pulmonary disease (COPD). Methods A QCC team was established to conduct problem-solving QCC activities. The current situation and factors of inhalants usage in COPD patients were analyzed. Targeted nursing countermeasures were carried out including comprehensive health education, standard operating procedure, enhanced training and evaluation, and diversified exercise of respiratory function. Results The accuracy rate of inhalants usage in COPD patients was increased form 58. 25% before implementation of QCC activities to 83. 06% after implementation of QCC activities. Conclusion The QCC is effective to improve the accuracy of inhalants usage in COPD patients. (目的 开展品管圈活动提高慢性阻塞性肺疾病(COPD)患者吸入剂的规范使用率。方法 成立品管圈圈组, 开展问题解决型品管圈活动, 通过现状把握、原因分析、制定了针对性的对策并予以实施, 包括打造无死角的宣教环境, 简单化、专业化、标准化完善操作流程, 加强培训夯实知识、质控考核提高水平和多元化、精细化进行呼吸功能锻炼。结果 COPD患者吸入剂的规范使用率由品管圈活动开展前的58. 25%上升至品管圈活动开展后的83. 06%。结论 品管圈活动能够提高COPD患者吸入剂的规范使用率。