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L-Cysteine inhibits root elongation through auxin/PLETHORA and SCR/SHR pathway in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2015年第2期57卷 186-197页

作者： Zhen Wang jie-Li mao Ying-Jun Zhao Chuan-You Li Cheng-Bin Xiang School of Life Sciences University of Science and Technology of China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Institute of Genetics and Developmental Biology The Chinese Academy of Sciences

L-Cysteine plays a prominent role in sulfur metabo- lism of plants. However, its role in root development is largely unknown. Here, we report that L-cysteine reduces primary root growth in a dosage-dependent manner. Elevating cellular L-cysteine level by exposing Arabidopsis thaliana seedlings to high L-cysteine, buthionine sulphoximine, or O-acetylserine leads to altered auxin maximum in root tips, the expression of quiescent center cell marker as well as the decrease of the auxin carriers PIN1, PIN2, PIN3, and PIN7 of primary roots. We also show that high L-cysteine significantly reduces the protein level of two sets of stem cell specific transcription factors PLETHORA1/2 and SCR/SHR. However, L-cysteine does not downregulate the transcript level of PiNs, PLTs, or SCR/SHR, suggesting that an uncharacterized post-transcriptional mechanism may regulate the accumulation of PIN, PLT, and SCR/SHR proteins and auxin transport in the root tips. These results suggest that endogenous L-cysteine level acts to maintain root stem cell niche by regulating basal- and auxin-induced expression of PLT1/2 and 5CR/SHR. L-Cysteine may serve as a link between sulfate assimilation and auxin in regulating root growth.

关键词： Auxini L-cysteine PIN PLETHORA root stem cell root system architecture

Synthesis of bacillamide 3 and its analogue

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Chinese Chemical Letters 2009年第10期20卷 1195-1197页

作者： Duo Li Hai Shen Yang Qing Cui Shen jie mao Xiao Hua Xu State Key Laboratory of Elemento-Organic Chemistry Nankai University Tlanjin 300071 China

The bacillamide 1 is a new algaecide from the marine bacterium Bacillus sp. SY-1. Its analogues bacillamide 3 and alkaloid 4 were firstly synthesized effectively from D-alanine. The key step was a coupling reaction via the mixed anhydride. All structures were confirmed by IH NMR and 13C NMR. The final compounds were confirmed by 1H NMR, 13C NMR and HRMS and the results are consistent with the reported natural products.

关键词： Bacillamide Thiazole rings Tryptamide Synthesis

基于SSA-VMD和SVM的滚珠丝杠副故障诊断

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机床与液压 2024年第12期52卷 231-238页

作者：左乾君陈国华毛杰张帅伟周博张智洋张秀琴湖北文理学院机械工程学院湖北襄阳441053 重庆渝江压铸股份有限公司重庆401123

针对滚珠丝杠副故障特征提取困难的问题,提出一种基于麻雀搜索算法优化变分模态分解算法(SSA-VMD)结合支持向量机(SVM)的滚珠丝杠副故障诊断方法。以最小包络熵作为SSA的适应度函数,对VMD参数进行自主寻优;运用IMF能量值对分解信号进行... 详细信息

针对滚珠丝杠副故障特征提取困难的问题,提出一种基于麻雀搜索算法优化变分模态分解算法(SSA-VMD)结合支持向量机(SVM)的滚珠丝杠副故障诊断方法。以最小包络熵作为SSA的适应度函数,对VMD参数进行自主寻优;运用IMF能量值对分解信号进行筛选重构,去除噪声和无关成分的干扰;最后提取重构信号的8类时域特征参数和5类频域特征参数作为特征向量集,导入SVM进行故障识别模型的训练。通过搭建滚珠丝杠副故障诊断实验平台采集振动信号,分别采用SSA-VMD、VMD、EMD方法进行信号分解提取故障特征。实验结果表明:与VMD和EMD相比,SSA-VMD能针对不同的信号自主选择最优的VMD参数进行信号分解,能准确识别滚珠丝杠副故障类型,证明了基于SSA-VMD的滚珠丝杠副故障诊断的可行性和准确性。

关键词：滚珠丝杠副变分模态分解(VMD) 麻雀搜索算法(SSA) 故障诊断

Low density lipoprotein cholesterol level inversely correlated with coronary flow velocity reserve in patients with Type 2 diabetes

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Journal of Geriatric Cardiology 2013年第2期10卷 159-164页

作者： jie Yu Jiang-Li Han Li-Yun He Xin-Heng Feng Wei-Hong Li jie-Ming mao Wei Gao Guang Wang Department of Cardiology Peking University Third Hospital Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China Department of Endocrinology Beijing Chaoyang Hospital Affiliated to Capital Medical University Beijing 100020 China

Objectives To evaluate the association of coronary artery endothelial function and plasma levels of low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) in patients with Type 2 Diabetes Mellitus (DM). Methods We investigated 90 participants from our institution between October 2007 to March 2010: non-DM(n = 60) and DM(n = 30). As an indicator of coronary endothelial dysfunction, we used non-invasive Doppler echocardiography to quantify coronary flow velocity reserve (CFVR) in the distal part of the left descending artery after rest and after intravenous adenosine administration. Results Plasma level of LDL-C was significantly higher in patients with DM than in non-DM (3.21 ±0.64 vs. 2.86 ±0.72 mmo/L, P < 0.05), but HDL-C level did not differ between the groups (1.01 ±0.17 vs. 1.05 ±0.19 mmo/L). Furthermore, the CFVR value was lower inDMpatients than non-diabetics (2.45 ±0.62 vs. 2.98 ±0.68, P < 0.001). Plasma levels of LDL-C were negatively correlated with CFVR in all subjects (r = ��0.35, P < 0.001; 95% confidence interval (CI): ��0.52 –��0.15) and in the non-DM(r = ��0.29, P < 0.05; 95% CI: ��0.51–��0.05), with an even stronger negative correlation in the DM group (r = ��0.42, P < 0.05; 95%CI: ��0.68 –��0.06). Age (β= ��0.019, s = 0.007, sβ= ��0.435, 95% CI: ��0.033 –��0.005, P = 0.008), LDL-C (β= ��0.217, s = 0.105, sβ= ��0.282, 95% CI: ��0.428 –��0.005, P = 0.045) remained independently correlated with CFVR in the DM group. However, we found no correlation between HDL-C level and CFVR in any group. Conclusions Diabetes may contribute to coronary artery disease (CAD) by inducing dysfunction of the coronary artery endothelium. Increased LDL-C level may adversely impair coronary endothelial function in DM. HDL-C may lose its endothelial-protective effects, in part as a result of pathological conditions, especially under abnormal glucose metabolism.

关键词： Coronary flow velocity reserve Diabetes mellitus Endothelial function High-density lipoprotein cholesterol Low-density lipoprotein cholesterol

Transcriptomic and machine learning analyses identify hub genes of metabolism and host immune response that are associated with the progression of breast capsular contracture

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Genes & Diseases 2024年第3期11卷 427-437页

作者： Yukun mao Xueying Hou Su Fu jie Luan Breast Plastic and Reconstructive Surgery Center Plastic Surgery HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100144China

Capsular contracture is a prevalent and severe complication that affects the post-operative outcomes of patients who receive silicone breast *** present,prosthesis replacement is the major treatment for capsular contracture after both breast augmentation procedures and breast reconstruction following breast cancer ***,the mecha-nism(s)underlying breast capsular contracture remains *** study aimed to identify the biological features of breast capsular contracture and reveal the potential underlying mechanism using RNA *** tissues from 12 female patients(15 breast capsules)were divided into low capsular contracture(LCC)and high capsular contracture(HCC)groups based on the Baker ***,41 lipid metabolism-related genes were identified through enrichment analysis,and three of these genes were identified as candidate genes by SVM-RFE and LASSO *** then compared the proportions of the 22 types of im-mune cells between the LCC and HCC groups using a CIBERSORT analysis and explored the Cor-relation between the candidate hub features and immune ***,PRKAR2B was positively correlated with the differentially clustered immune cells,which were M1 macro-phages and follicular helper T cells(area under the ROC=0.786).In addition,the expression of PRKAR2B at the mRNA or protein level was lower in the HCC group than in the LCC *** molecular mechanisms were identified based on the expression levels in the high and low PRKAR2B *** findings indicate that PRKAR2B is a novel diagnostic biomarker for breast capsular contracture and might also influence the grade and progression of capsularcontracture.

关键词： Biomarker Breastcapsular contracture Immune infiltration Machinelearning algorithms PRKAR2B

An Association between Immunosenescence and CD4^+CD25^+ Regulatory T Cells: A Systematic Review

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Biomedical and Environmental Sciences 2010年第4期23卷 327-332页

作者： LING WANG YAN XIE LI-JING ZHU TING-TING CHANG YAN-QING mao jie LI Clinical Immunology Laboratory The First Affiliated Hospital of Soochow University Suzhou 215006 Jiangsu China

Objective Age-related increment of the prevalence of CD4^＋CD25^＋ regulatory T （Treg） cells were described controversially, and whether such changes explain immune dysfunction in the elderly is still unclear. The aim of this systematic review is to evaluate the role of the Tregs in immunosenescence. Methods Medline and manual searches were performed to identify all published epidemiological and animal studies investigating the efficacy of the association between immunosenescence and Treg cells. Results It was founded that the frequency, phenotypic characteristics, and number/function of Tregs were altered significantly with aging. Medical conditions in individuals with advanced ageas well as apoptosis intensity of Treg cells had an impact on the accumulation of Tregs which in turn could deteriorate cytotoxic activity of CD8＋ T and NK cells and production of IL-2. The range of immune cells that could be suppressed by Treg cells was quite wide and covered CD4^＋CD25^＋ T cells, NK cells, dendritic cells and even monocytes. These changes were observed both in humans and experimental animals. Besides, it was believed that frequency of Tregs increased with age and was accompanied by intensified suppressive activity for Tregs in patients, for example, with Alzheimer disease （AD） and Parkinson disease （PD）. The impaired condition of CD4＋ T cells, so-called immunosenescence, rendered transplant recipients less responsive to an allogeneic kidney graft, an effect that was limited to transplant recipients who were aged over 60 years. Conclusions Treg cells are associated with immunosenescence. All these changes contribute to the aging-related decline of immune responses and lead to the higher risk of immune-mediated diseases, cancer or infections in aged individuals.

关键词： Aging Immunosenescence CD4^+CD25^+ T cell Treg Case-control studies Cohort studies Cross-sectional studies

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仪器偏心对纵横波衰减影响的正演实验

科学技术与工程 2024年第6期24卷 2339-2347页

作者：张远君伍东廖茂杰石学文蔡明章成广唐军油气资源与勘探技术教育部重点实验室(长江大学) 武汉430100 长江大学地球物理与石油资源学院武汉430100 中国石油集团工程技术研究院有限公司信息中心北京102206 中国石油西南油气田分公司页岩气研究院成都610056

近年来,水平井得到了越来越广泛的应用,在页岩气等非常规油气藏以及海上油气藏的勘探开发中发挥了至关重要的作用。但水平井测井在影响因素校正、资料处理和解释等方面尚存在诸多问题。针对仪器偏心对水平井声波测井响应影响的问题,开... 详细信息

近年来,水平井得到了越来越广泛的应用,在页岩气等非常规油气藏以及海上油气藏的勘探开发中发挥了至关重要的作用。但水平井测井在影响因素校正、资料处理和解释等方面尚存在诸多问题。针对仪器偏心对水平井声波测井响应影响的问题,开展了相关的物理模拟实验研究和数值模拟分析。提取了不同偏心率条件下的模式波的能量参数,分析了模式波能量随仪器偏心率的变化关系。结果表明,当仪器处于偏心状态时,模式波的能量均与仪器偏心率呈现类似负指数关系;仪器偏心率与模式波的能量衰减系数呈现S形曲线变化关系。研究结果有助于厘清仪器偏心对水平井声波测井响应的影响规律并为进一步开展仪器偏心对阵列声波测井响应影响校正方案研究提供指导。

关键词：水平井声波仪器仪器偏心物理模拟实验数值模拟模式波

A comparison between novel Gd_(2)Zr_(2)O_(7)and Gd_(2)Zr_(2)O_(7)/YSZ thermal barrier coatings fabricated by plasma spray-physical vapor deposition

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Rare Metals 2021年第8期40卷 2244-2253页

作者： Ren-Bo Zhu Jian-Peng Zou jie mao Zi-Qian Deng Xiao-Feng Zhang Chun-Ming Deng Min Liu School of Materials Science and Engineering University of New South WalesSydneyNSW2052Australia State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China National Engineering Laboratory for Modern Materials Surface Engineering Technology and Key Laboratory of Guangdong for Modern Surface Engineering Technology Guangdong Institute of New MaterialsGuangzhou510651China

Spherical Gd_(2)Zr_(2)O_(7)hollow powders with a mean size of 8.8μm were fabricated as feedstock for thermal barrier coatings(TBCs)by *** single-ceramic-layer(SCL)Gd_(2)Zr_(2)O_(7)TBCs and double-ceramic-layer(DCL)Gd_(2)Zr_(2)O_(7)/YSZ TBCs with quasicolumnar structure were successfully fabricated by plasma spray-physical vapor deposition(PS-PVD).Tensile and water-quenching tests were applied to evaluate TBCs *** results show that adhesion strength of SCL Gd_(2)Zr_(2)O_(7)TBCs and DCL Gd_(2)Zr_(2)O_(7)/YSZ TBCs is36.5 MPa and 15.4 MPa,*** delamination of SCL Gd_(2)Zr_(2)O_(7)TBCs and DCL Gd_(2)Zr_(2)O_(7)/YSZ TBCs in the tensile test takes place at the middle and bottom of Gd_(2)Zr_(2)O_(7)layer,respectively,due to relatively lower fracture toughness of Gd_(2)Zr_(2)O_(7)*** 40 cycles of water-quenching test,DCL Gd_(2)Zr_(2)O_(7)/YSZ TBC surface keeps relatively intact,while SCL Gd_(2)Zr_(2)O_(7)TBC surface shows 20%visible destroyed regions,which demonstrates that DCL Gd_(2)Zr_(2)O_(7)/YSZ TBCs have a better thermal shock resistance than SCL Gd_(2)Zr_(2)O_(7)*** cracks in the SCL system propagate near thermally grown oxide(TGO)due to thermal mismatch and TGO growing stress,while cracks in the DCL system propagate in the Gd_(2)Zr_(2)O_(7)layer due to its relatively lower fracture toughness.

关键词： Plasma spray-physical vapor deposition Thermal barrier coatings Gd_(2)Zr_(2)O_(7) Thermal shock resistance Adhesion strength

Self-healing,Stretchable,Temperature-Sensitive and Strain-Sensitive Hydrogel-based Flexible Sensors

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Chinese Journal of Polymer Science 2023年第3期41卷 334-344,I0005页

作者： Chun-Xia Zhao Min Guo jie mao Yun-Tao Li Yuan-Peng Wu Hua Guo Dong Xiang Hui Li School of Materials Science and Engineering Southwest Petroleum UniversityChengdu 610500China The Center of Functional Materials for Working Fluids of Oil and Gas Field Sichuan Engineering Technology Research Center of Basalt Fiber Composites Development and ApplicationSouthwest Petroleum UniversityChengdu 610500China State Key Lab of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

Flexible hydrogels have shown promise as strain sensors in medical monitoring,human motion detection and intelligent *** a hydrogel strain sensor,certain challenges need to be urgently addressed for practical applications,such as the damage caused by external effects,leading to equipment failure,and the inability to perceive ambient temperature,resulting in single ***,a stretchable,self-healing and dual temperature-strain sensitive hydrogel,with a physically-crosslinked network,is designed by constructing multiple dynamic reversible *** oxide(GO)and iron ions(Fe^(3+))act as dynamic bridges in the cross-linked network and are mediated by the covalent and hydrogen bonding,rendering excellent stretchability to the *** reversible features of coordination interactions and hydrogen interactions endow excellent recoverability and self-healing ***,the incorporated N-isopropyl acrylamide(NIPAM)provides excellent temperature responsiveness to the hydrogel,facilitating the detection of external temperature ***,the hydrogels exhibited strain-sensitivity,with a wide working range of 1%-300%,fast response and electrical stability,which can be used as flexible sensors to monitor body motions,e.g.,speaking and the bending of finger,wrist,elbow and ***,the hydrogel possesses dual sensory capabilities,combining external temperature and strain,for potential applications in wearable multifunctional sensing devices.

关键词： Hydrogel sensor Self-healing Dual temperature-strain sensitive Monitor body motions