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电感耦合等离子体质谱仪法在南水北调东线工程应急监测中的应用

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中国标准化 2024年第9期 212-216页

作者：朱良琪陈良骥尼庆伟刘梅中国南水北调集团东线有限公司

建立电感耦合等离子体质谱仪法测定地表水中8种常见金属元素的分析方法,用于南水北调东线工程突发水污染应急监测。在现行水质金属指标标准检验方法的基础上,基于车载型电感耦合等离子体质谱仪具有高移动性、环境变化大及移动电源供电... 详细信息

建立电感耦合等离子体质谱仪法测定地表水中8种常见金属元素的分析方法,用于南水北调东线工程突发水污染应急监测。在现行水质金属指标标准检验方法的基础上,基于车载型电感耦合等离子体质谱仪具有高移动性、环境变化大及移动电源供电等特性,对检测方法、检测质量控制和检测结果可靠性进行分析确认。结果显示8种金属元素的校准曲线相关系数(R2)均大于0.999,定量限范围为0.019~0.47μg/L。加标低中高3种不同浓度时,纯水和河水的加标回收率为90.4%~115%,相对标准偏差1.6%~8.9%。稳定性测试加标回收率均为96.5%~104%,相对标准偏差均为2.0%~3.7%。与传统便携式快速测定水中金属元素的方法相比具有检出限低、分析速率快、稳定性好和多指标同时测定的优势,为南水北调东线工程突发水污染应急监测提供技术支撑。

关键词：南水北调电感耦合等离子体质谱仪应急监测金属元素地表水

甜菜碱对低温下苜蓿种子萌发中呼吸电子传递的影响

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草地学报 2024年第3期32卷 763-771页

作者：王婕刘美君赵尧尧张政卫丹丹龚梁祝胡轩铭新疆农业大学草业学院西部干旱区草地资源与生态教育部重点实验室新疆草地资源与生态重点实验室新疆乌鲁木齐830052 忻州师范学院山西忻州034000

呼吸作用是种子萌发的唯一能量来源。本研究以‘新牧4号’紫花苜蓿(Medicago sativa L.‘Xinmu No.4’)为试验材料,探究了甜菜碱对低温下苜蓿萌发种子呼吸电子传递的影响。结果表明:低温抑制苜蓿种子的发芽率,但没有终止种子萌发进程;... 详细信息

呼吸作用是种子萌发的唯一能量来源。本研究以‘新牧4号’紫花苜蓿(Medicago sativa L.‘Xinmu No.4’)为试验材料,探究了甜菜碱对低温下苜蓿萌发种子呼吸电子传递的影响。结果表明:低温抑制苜蓿种子的发芽率,但没有终止种子萌发进程;延长萌发时间,最终种子的萌发率与20℃下无差异。外施15 mmol·L^(-1)甜菜碱提高了低温下种子发芽率、发芽势、发芽指数,缩短低温下种子全部萌发的时间从而促进种子萌发,且温度越低,促进作用越大。甜菜碱提高了低温下种子呼吸速率,产生ATP的细胞色素C氧化酶呼吸速率及其在总呼吸中的占比显著增加,保证了苜蓿种子萌发所需的能量。此外,甜菜碱增加了交替氧化酶呼吸速率,减少了活性氧的产生,并且提高了苜蓿种子内SOD,POD,CAT活性,从而减少了H_(2)O_(2)的积累,有效缓解低温下种子的氧化伤害,维持低温下苜蓿种子较高的萌发速度,缩短萌发时间。

关键词：紫花苜蓿低温胁迫甜菜碱种子萌发呼吸电子传递

难熔金属及金属碳/氧化物粉体制备技术研究进展

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航空学报 2024年第3期45卷 46-60页

作者：魏玉鹏陈珊王雅婷王东新于艳红张萌肖荣振朱亮程越伟兰州理工大学材料科学与工程学院兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 西北稀有金属材料研究院宁夏有限公司石嘴山753000 稀有金属特种材料国家重点实验室石嘴山753000

难熔金属及金属碳/氧化物具有高熔点、高温稳定性、强耐腐蚀性等优异特性,在燃气叶片、电子管、火箭引擎、切削刀具、高温热元件、涡轮喷嘴等高温高压、强腐蚀性等环境下被广泛应用。本文介绍了难熔金属及金属碳/氧化物粉体的应用,梳理... 详细信息

难熔金属及金属碳/氧化物具有高熔点、高温稳定性、强耐腐蚀性等优异特性,在燃气叶片、电子管、火箭引擎、切削刀具、高温热元件、涡轮喷嘴等高温高压、强腐蚀性等环境下被广泛应用。本文介绍了难熔金属及金属碳/氧化物粉体的应用,梳理了难熔金属及金属碳/氧化物粉体的机械法、还原法、燃烧法、溶胶-凝胶法、水热法、微波法、沉淀法、热解法、爆炸法和等离子体法等制备工艺,并比较各种工艺在制备难熔金属及金属碳/氧化物粉体过程中的优缺点;重点评述难熔金属及金属碳/氧化物Mo、W、Ta、WC、ZrC、TiC、CeO_(2)、ZrO_(2)、Y_(2)O_(3)等粉体的研究现状,并展望了难熔粉体的发展方向,为难熔粉体的制备工艺和应用提供参考。

关键词：难熔金属难熔粉体金属碳化物粉体金属氧化物粉体制备方法

Dysfunction of autophagy as the pathological mechanism of motor neuron disease based on a patient-specific disease model

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Neuroscience Bulletin 2015年第4期31卷 445-451页

作者： Dan-Jing Yang liang zhu Jie Ren Rong-Jie Ma Hongwen zhu Jun Xu Advanced Institute of Translational Medicine Tongji University East Hospital Tongji University School of Medicine Tianjin Hospital Tianjin Academy of Integrative Medicine

Autophagy is the main catabolic pathway in cells for the degradation of impaired proteins and organelles. Accumulating evidence supports the hypothesis that dysfunction of autophagy, leading to an imbalance of proteostasis and the accumulation of toxic proteins in neurons, is a central player in the pathogenesis of neurodegenerative diseases such as Alzheimer＇s disease, Parkinson＇s disease, and amyotrophic lateral sclerosis （ALS）. The clinical pathology of ALS is complex and many genes associated with autophagy and RNA processing are mutated in patients with the familial form. But a causal relationship between autophagic dysfunction and ALS has not been fully established. More importantly, studies on the pathological mechanism of ALS are mainly based on animal models that may not precisely recapitulate the disease itself in human beings. The development of human iPSC techniques allows us to address these issues directly in human cell models that may profoundly influence drug discovery for ALS.

关键词： motor neuron disease iPSC autophagy amyotrophic lateral sclerosis spinal muscular atrophy

基于LSTM神经网络深度序列机械钻速实时预测

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西安石油大学学报（自然科学版） 2024年第1期39卷 122-128页

作者：冯义朱亮杨立军李慎越席俊卿陈芳纪慧中石油吐哈油田分公司工程技术研究院新疆哈密839000 油气钻完井技术国家工程研究中心湖北武汉430100 油气钻采工程湖北省重点实验室(长江大学) 湖北武汉430100 长江大学石油工程学院湖北武汉430100

机械钻速是钻井优化、缩短钻井周期的关键因素,传统的机械钻速预测大多是在钻井后进行钻井分析,预测效率和精度低、地层适用性不广。为了以更高效的方法预测得到高精度机械钻速,提出基于长短期记忆(LSTM)神经网络的深度序列机械钻速预... 详细信息

机械钻速是钻井优化、缩短钻井周期的关键因素,传统的机械钻速预测大多是在钻井后进行钻井分析,预测效率和精度低、地层适用性不广。为了以更高效的方法预测得到高精度机械钻速,提出基于长短期记忆(LSTM)神经网络的深度序列机械钻速预测方法。采集实时钻井数据集,使用皮尔逊相关系数衡量各特征之间的相关性,筛选出井深、伽玛射线、地层密度、孔隙压力、井径、钻时、排量、钻井液密度等8个参数。构建LSTM神经网络模型,训练LSTM模型并预测ROP,对预测结果进行分析,并用决定系数(R^(2))、均方根误差(RMSE)、平均绝对百分比误差(MAPE)等指标对LSTM模型、BP模型和SVM模型性能进行对比分析。结果表明:LSTM模型其R^(2)、RMSE和MAPE的值分别为0.948、1.151和17.075,相较于BP模型和SVM模型,其R^(2)更大,RMSE和MAPE较小,说明LSTM模型预测性能更好。该方法有助于钻井工程师和决策者提前获得钻井信息,从而更好地规划钻井作业,缩短钻井周期,同时为钻井参数预测提供新的途径,能改善以往预测方法在处理复杂地层问题时效率不高、预测精度低等问题。

关键词：机械钻速 LSTM神经网络深度序列实时预测人工智能深度学习

High level of circPTN promotes proliferation and stemness in gastric cancer

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BIOCELL 2021年第6期45卷 1521-1526页

作者： KEWEI GAO JIANGFENG HU YI ZHOU liang zhu Department of Gastroenterology Shanghai Changzheng HospitalThe Second Military Medical UniversityShanghai200001China Department of Gastroenterology Shanghai First People’s HospitalShanghai200003China Department of Gastroenterology Shanghai Hospital of Integrated Traditional Chinese and Western MedicineShanghai200003China

Increasing evidence proves that circular RNAs(circRNAs)play an important role in regulating the biological behaviors of *** central purpose of this research was to investigate the functions of circRNA in gastric *** utilization of real-time PCR was to test circPTN expression in gastric cancer *** counting colony formation assays,CCK-8 assay,and EdU assay were used to investigate *** assay was applied to investigate *** discovered that circPTN was highly expressed in gastric cancer *** expression of circPTN inhibits gastric cancer cell proliferation and *** expression of circPTN promotes gastric cancer cell proliferation and ***,we discovered that circPTN could accelerate self-renewal and increase the expression of stemness *** results of our study suggested that a high level of circPTN expression promotes the proliferation and stemness of gastric cancer cells.

关键词： circPTN Gastric cancer Proliferation and stemness

Automatic pectoral muscle boundary detection in mammograms based on Markov chain and active contour model

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第2期11卷 111-118页

作者： Lei WANG Miao-liang zhu Li-ping DENG Xin YUAN School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Automatic pectoral muscle removal on medio-lateral oblique (MLO) view of mammogram is an essential step for many mammographic processing algorithms. However,it is still a very difficult task since the sizes,the shapes and the intensity contrasts of pectoral muscles change greatly from one MLO view to another. In this paper,we propose a novel method based on a discrete time Markov chain (DTMC) and an active contour model to automatically detect the pectoral muscle boundary. DTMC is used to model two important characteristics of the pectoral muscle edge,i.e.,continuity and uncertainty. After obtaining a rough boundary,an active contour model is applied to refine the detection results. The experimental results on images from the Digital Database for Screening Mammography (DDSM) showed that our method can overcome many limitations of existing algorithms. The false positive (FP) and false negative (FN) pixel percentages are less than 5% in 77.5% mammograms. The detection precision of 91% meets the clinical requirement.

关键词： Pectoral muscle Markov chain Active contour Mammogram

Isolation and Characterization of Radiation-resistant Lung Cancer D6-R Cell Line

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Biomedical and Environmental Sciences 2008年第4期21卷 339-344页

作者： QI-CHUN WEI LI SHEN SHU ZHENG YONG-liang zhu Ministry of Education Key Laboratory of Cancer Prevention and Intervention Zhejiang University Hangzhou 310009 Zhejiang China Department of Radiation Oncology the Second Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310009 Zhejiang China

Objective To isolate an isogenic radioresistant cancer cell line after fractioned X-ray radiation and characterize the resistant cells. Methods D6 cells were exposed to repeated X-ray irradiation, and after a total dose of 5200 cGy in 8 fractions, a radioresistant monoclone D6-R was obtained. The radiosensitivity and drug sensitivity of the novel radioresistant D6-R cells, together with their parent D6 cells, were measured using clonogenic assay and MTT assay respectively. Cell cycle distribution was analyzed by flow cytometry. Fluorescence microscopy and flow cytometry were applied for apoptosis detection Comet assay was used for the detection of DNA damage and repair. Results D6-R cells showed higher and broader initial shoulder （D0=2.08 Gy, Dq=1.64 Gy, N=2.20） than the parent D6 cells （D0=1.84 Gy, Dq=0.34 Gy, N=1.20）. They were 1.65-fold more radioresistant than D6 cells in terms of SF2 （63% vs 38%） and were more resistant to ADM （3.15-fold） and 5-FU （3.86-fold） as compared with the latter. It was found that D6-R cells had higher fractions of cells in S phase （53.4% vs 37.8%） and lower fractions of cells in G1 （44.1% vs 57.2%） and G2-M phase （2.5% vs 5%）. There was no difference in radiation-induced apoptosis between D6-R and D6 cells. D6-R cells showed less initial DNA damage and increased capacity in DNA repair after irradiation, as compared with the parent cells. Conclusions D6-R cells have been isolated by exposing the parental D6 cells to repeated irradiation. The difference in cell cycle pattern together with the induction and repair of DNA damage might, at least partially, explain the mechanism of the radioresistance.

关键词： Radiosensitivity Chemosensitivity Cell cycle Apoptosis DNA damage DNA repair

Phosphine production in anaerobic wastewater treatment under tetracycline antibiotic pressure

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Journal of Environmental Sciences 2018年第7期30卷 239-250页

作者： Meiqing Lu Xiaojun Niu Weiyi Chen zhu liang Sheng You Xiaohong Gu School of Environment and Energy South China University of Technology Guangzhou 510006 China State Key Laboratory of Lake Science and Environment Nanjing 210008 China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen Key Laboratory of Soil and Groundwater Pollution Control Shenzhen 518055 China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control Guangzhou 510640 China China Water Resources Pearl River Planning Surveying & Designing Co. Ltd. Guangzhou 510640 China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSouth China University of Technology Guangzhou Higher Education Mega Centre Guangzhou 510006 China

The influence of tetracycline（TC） antibiotics on phosphine（PH3） production in the anaerobic wastewater treatment was studied. A lab-scale anaerobic baffled reactor with three compartments was employed to simulate this process. The reactor was operated in a TC-absence wastewater and 250 μg/L TC-presence wastewater for three months after a start-up period,respectively. The responses of p H, oxidation–reduction potential（ORP）, chemical oxygen demand（COD）, total phosphorus（TP）, enzymes activity（dehydrogenase and acid phosphatase）,and microbial community were investigated to reveal the effect of TC on PH3 *** suggested that the dehydrogenase（DH） activity, acid phosphatase（ACP） activity and COD have positive relationship with PH3 production, while p H, ORP level and the TP in liquid phase have negative relationship with PH3 production. With prolonged TC exposure, decrease in p H and increase in DH activity are beneficial to PH3 production, while decrease in COD and ACP activity are not the limiting factors for PH3 production.

关键词： Tetracycline antibiotic Anaerobic Wastewater treatment Phosphine production