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河北承德地区土壤硒元素地球化学特征、地质成因及其生态环境评价

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中国地质 2024年第4期51卷 1290-1303页

作者：魏浩卫晓锋王京彬朱苏加杨帆梁钊田晓霞李炜贾文茹于开宁河北地质大学河北省高校生态环境地质应用技术研发中心河北石家庄050031 河北地质大学河北省战略性关键矿产资源重点实验室河北石家庄050031 中色紫金地质勘查(北京)有限责任公司北京100012 河北省科学院地理科学研究所河北石家庄050011 中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 北京市农林科学院草业花卉与景观生态研究所北京100097

【研究目的】查明承德地区土壤硒的分布特征及地质成因,为当地土壤硒的勘查及有效利用提供科学依据。【研究方法】通过地质调查查明该区成土母质类型,利用X-射线荧光光谱法、电感耦合等离子体发射光谱法、凯氏定氮法等获取了553个土壤... 详细信息

【研究目的】查明承德地区土壤硒的分布特征及地质成因,为当地土壤硒的勘查及有效利用提供科学依据。【研究方法】通过地质调查查明该区成土母质类型,利用X-射线荧光光谱法、电感耦合等离子体发射光谱法、凯氏定氮法等获取了553个土壤样品及66件岩矿石样品中硒及多个元素的含量,并利用SPSS软件分析数据,结合地质作用分析地质成因。【研究结果】研究区成土母质大致分为9类,表层土壤中硒含量最小值为0.016mg/kg,最大值为0.743 mg/kg,平均值为0.17 mg/kg,土壤平均硒含量仅为全国土壤平均硒含量的1/2,处于缺乏等级。铁矿石、金矿石、铅锌矿石中硒含量均值分别为0.860 mg/kg、1.233 mg/kg、3.365 mg/kg,明显高于各类矿石的尾矿及围岩。【结论】承德地区土壤硒整体含量很低,主要决定于成土母质,分布特征受控于地质建造。富硒土壤区域集中在隆化县南部(A区)、承德市南部(B区)(双滦区、双桥区)、宽城县东部(C区)。C区属于“岩石风化型”,与含硒量高的原生碳酸盐岩+碳质泥岩地层组合有关;B区属于“成矿伴生型”,与铅锌矿成矿过程中硒与金属硫化物的伴生关系及硒与硫的替代关系有关;A区属于“河道沉积型”,与河道沉积过程中河湖冲动力驱动、有机质的吸附作用有关。承德南部富硒区域具有发展林果经济的天然优势,围场县处于低硒环境,是引发克山病等地方病流行的因素之一。

关键词：土壤硒分布特征相关性分析地质成因农业地质调查工程承德市河北省

Dynamic recrystallization behavior of GH4169G alloy during hot compressive deformation

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Journal of Materials Science & Technology 2019年第9期35卷 1851-1859页

作者： Dan jia wenru Sun Dongsheng Xu Fang Liu University of Chinese Academy of Sciences Beijing100049China Institute of Metal Research Chinese Academy of SciencesShenyang110016China

The microstructure evolutions and nucleation mechanisms of GH4169G alloy were studied by optical microscope, electron backscatter diffraction (EBSD) and transmission electron microscope (TEM). The hot compression tests were performed different imposed reductions in the range of true strain from 0.12 to 1.2 at the temperatures of 930 °-1050 ° with strain rates of 0.01 s^-1-l s^-1. It is found that cumulative and local misorientation increase firstly and then decrease when the strain is increased due to the progress of dynamic recrystallization (DRX). The low angle boundaries (LAGBs) rapidly develop to high angle boundaries (HAGBs) at relatively high deformation temperature or the low strain rate. There are three DRX mechanisms observed for GH4169 G alloy during hot deformation. Discontinuous dynamic recrystallization (DDRX) as the dominant mechanism for GH4169 G alloy is characterized by typical necklace structures and bulged-original boundaries. Besides, different deformation bands with dislocation cells formed in deformed matrix at low temperature and large strain, which indicates that continuous dynamic recrystallization (CDRX) contributed to the DRX process. The twin boundaries lost their coherent characteristics and provide sites for nucleation, which also accelerates the nucleation of DRX.

关键词： GH4169G alloy Dynamic recrystallization Nucleation mechanism

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不同发育阶段新月形沙丘表面粒度特征

沙漠与绿洲气象 2019年第6期13卷 111-118页

作者：俞祥祥李生宇马学喜贾文茹中国科学院新疆生态与地理研究所新疆乌鲁木齐830011 中国科学院大学北京100049

以塔克拉玛干沙漠腹地垄间平地新月形沙丘的4个发育阶段(饼状沙丘(PD)、盾状沙丘(SD)、雏形新月形沙丘(PCD)、新月形沙丘(TCD))为研究对象,对沙丘表面不同地貌部位的沙物质取样并进行粒度分析,以期发现新月形沙丘不同发育阶段表面粒度... 详细信息

以塔克拉玛干沙漠腹地垄间平地新月形沙丘的4个发育阶段(饼状沙丘(PD)、盾状沙丘(SD)、雏形新月形沙丘(PCD)、新月形沙丘(TCD))为研究对象,对沙丘表面不同地貌部位的沙物质取样并进行粒度分析,以期发现新月形沙丘不同发育阶段表面粒度的变化规律,结果表明:4种沙丘丘顶或临近丘顶处细砂及极细砂含量最小、粒径最粗、分选性最差,向两侧细砂及极细砂含量逐渐增大、粒径逐渐变细、分选逐渐变好。各发育阶段之间沙粒级配、平均粒径、分选系数的变化规律则需区分不同地貌部位。在迎风坡这3者没有较大差异;在背风坡,细砂及极细砂含量、平均粒径、分选系数均随着沙丘的发育而增大。另外,峰度和偏度并不随着新月形沙丘的发育有明显的变化,均属于近对称中等峰态且为单峰。

关键词：粒度特征新月形沙丘不同发育阶段塔克拉玛干沙漠

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青藏高原沙漠化土地空间分布及区划

中国沙漠 2018年第4期38卷 690-700页

作者：李庆张春来周娜沈亚萍伍永秋邹学勇李姣贾文茹王雪松河北省科学院地理科学研究所/河北省地理信息开发应用工程技术研究中心河北石家庄050021 北京师范大学地表过程与资源生态国家重点实验室/防沙治沙教育部工程研究中心北京100875 河北经贸大学管理科学与工程学院河北石家庄050021

利用野外调查数据、遥感影像和已有研究成果,构建了一套适用于青藏高原沙漠化土地的分类分级指标体系及遥感解译标志。以此为基础,选取目视解译法监测青藏高原沙漠化土地的空间分布特征。结果表明:2015年青藏高原沙漠化土地面积392 913k... 详细信息

利用野外调查数据、遥感影像和已有研究成果,构建了一套适用于青藏高原沙漠化土地的分类分级指标体系及遥感解译标志。以此为基础,选取目视解译法监测青藏高原沙漠化土地的空间分布特征。结果表明:2015年青藏高原沙漠化土地面积392 913km^2,占高原土地总面积的15.1%,主要包括沙质沙漠化土地、砾质沙漠化土地和风蚀残丘3种类型。沙漠化土地以中度和轻度沙漠化土地为主,重度和极重度沙漠化土地面积仅占沙漠化土地总面积的12.2%。空间上,沙漠化土地集中分布在高原的北部和西部地区,其他地区零散分布。自东南向西北,沙漠化土地面积逐渐增大,沙漠化程度不断加重。以沙漠化土地空间分布数据(面积、类型、程度、空间特征和驱动因素)为基础,结合气候、地貌、第四纪沉积物和人类活动等数据,将青藏高原沙漠化区划分为雅鲁藏布江半干旱高山宽谷沙漠化区、藏北青南高寒高原面沙漠化区、柴达木干旱盆地沙漠化区、黄河上游半干旱河流盆地沙漠化区和"三江"流域湿润半湿润高山沙漠化区。

关键词：沙漠化土地空间分布控制因素空间区划青藏高原

Effect of cooling rate on phosphorus segregation behavior and the corresponding precipitation of γ’’ and γ’ phases in IN718 alloy

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Journal of Materials Science & Technology 2019年第7期35卷 1485-1490页

作者： Anwen Zhang Sha Zhang Fang Liu Feng Qi Xiaoyu Yao Yuanguo Tan Dan jia wenru Sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China College of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Effect of segregation behaviors of P at different cooling rates on the precipitation of γ" and γ' phases and the corresponding strength are investigated. The precipitation of γ" and γ' phases during cooling is sensi-tive to P concentration. With increasing the concentration of Pf the amount of γ" and γ' particles increases after air cooling. With decreasing the cooling rate, the accelerating effect of P on the precipitation of γ" and γ' phases decreased first and then increased, which demonstrates the concentration of P dissolved in the grain interior decreases first and then increases. The different effects of P on γ"and γ' phases with different cooling rates were analyzed by the kinetic characteristic of nonequilibrium grain-boundary seg-regation. The characteristic of nonequilibrium grain-boundary segregation of P in superalloy is further confirmed, and the phenomenon caused by critical cooling rate is captured.

关键词： Phosphorus IN718alloy Segregation behavior γ" and γ' phases

microRNA-21a-5p/PDCD4 axis regulates mesenchymal stem cell-induced neuroprotection in acute glaucoma

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Journal of Molecular Cell Biology 2017年第4期9卷 289-301页

作者： wenru Su Zuohong Li Yu jia Yingting Zhu Wenjia Cai Peixing Wan Yingying Zhang Song Guo Zheng Yehong Zhuo State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 China Department of Clinic Immunology The Third Affiliated Hospital at Sun Yat-sen University Guangzhou 510630 China Division of Rheumatology Department of Medicine Penn State Milton S. Hershey Medical Center Hershey PA 17033 USA

Mesenchymal stem ceils （MSCs） have been demonstrated to have promising therapeutic benefits for a variety of neurological dis- eases; however, the underlying mechanisms are poorly understood. Here, we showed that intravitreal infusion of MSCs promoted retinal ganglion cell （RGC） survival in a mouse model of acute glaucoma, with significant inhibition of microglial activation, production of TNF-α, IL-1β, and reactive oxygen species, as well as caspase-8 and caspase-3 activation. In vitro, MSCs inhibited both caspase-8-mediated RGC apoptosis and microgUal activation, partly via the action of stanniocalcin 1 （STCl）. Furthermore, we found that microRNA-21a-Sp （miR-21） and its target, PDCD4, were essential for STC1 production and the neuroprotective property of MSCs in vitro and in vivo. Importantly, miR-21 overexpression or PDCD4 knockdown augmented MSC-mediated neuroprotective effects on acute glaucoma. These data highlight a previously unrecognized neuroprotective mechanism by which the miR-21/ PDCD4 axis induces MSCs to secrete STC1 and other factors that exert neuroprotective effects. Therefore, modulating the miR- 21/PDCD4 axis might be a promising strategy for clinical treatment of acute glaucoma and other neurological diseases.

关键词： mesenchymal stem ceils microRNA neuroprotection glaucoma neurological diseases

Association Between rs1344706 of ZNF804A and Schizophrenia: A Meta-analysis

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Genomics, Proteomics & Bioinformatics 2014年第6期12卷 292-296页

作者： Meiyan Zhu Tongyang Liu Jihong Zhang Shuting jia wenru Tang Ying Luo Lab of Molecular Genetics of Aging & Tumor Medical Faculty Kunming University of Science and Technology

Schizophrenia is one of the most serious mental diseases found in humans. Previous studies indicated that the single nucleotide polymorphism（SNP） rs1344706 in the gene ZNF804 A encoding zinc finger protein 804 A was associated with schizophrenia in Caucasian population but not in Chinese Han population. However, current results are conflicting in Asian population. In the present study, a meta-analysis was performed to revisit the association between rs1344706 and the risk of schizophrenia in Asian, Caucasian and other populations. Electronic search of Pub Med database identified 25 case–control studies with available genotype frequencies of rs1344706 for the meta-analysis,involving a total of 15,788 cases and 22,654 controls. A pooled odds ratio（OR） with 95% confidence interval（CI） was used to assess the association. The current meta-analysis showed an association between rs1344706 and schizophrenia in Caucasian populations（P = 0.028, OR = 1.138, 95% CI：1.014–1.278; P = 0.004 for heterogeneity） and Asian populations（P = 0.008, OR = 1.092, 95%CI： 1.023–1.165; P = 0.001 for heterogeneity）, but not in other populations（P = 0.286,OR = 1.209, 95% CI： 0.853–1.714, P = 0.120 for heterogeneity）. Egger’s test（P 〉 0.05） and Begg’s test（P 〉 0.05） are both suggestive of the lack of publication bias for the included studies. Thus, the absence of association in other populations suggests a genetic heterogeneity in the susceptibility of schizophrenia and demonstrates the difficulties in replicating genome-wide association study findings regarding schizophrenia across different ethnic populations. To validate the association between rs1344706 and schizophrenia, further studies with larger participant populations worldwide are needed.

关键词： Meta-analysis ZNF804A Schizophrenia Association Caucasians Asians

The Oncogenic Effect of p53 Mutant p53N236S Found in ALT Tumorigenic Cell Lines Derived from Senesced Werner Syndrome MEFs

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The Oncogenic Effect of p53 Mutant p53N236S Found in ALT Tum...

Development of a Rehabilitation Instrument of Neurological Training for Cervical Spine

第七届全国医学生物化学与分子生物学和第四届全国临床应用生物化学与分子生物学联合学术研讨会暨医学生化分会会员代表大会

作者： Shuting jia Qingxiong Meng wenru Tang Ying Luo Lab of Molecular Genetics of Aging & Tumor Faculty of Life Science and Technology & Faculty of Environmental Science and EngineeringKunming University of Science & Technology

Objeetive:Telomeres of tumor cells may be maintained by telomerase or by alternative lengthening of telomeres(ALT).We aimed to understand the loss and gain of function of p53 mutants in ALT tumor and provide the basis... 详细信息

关键词： p53 mutant ALT tumorigenesis Ras gain of function

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Journal of Biomedical Science and Engineering 2022年第11期15卷 269-279页

作者： Chenyu Wang Zhigang Hu Luyang jia Lei Sun Xiaohua Wang wenru Zhao School of Medical Technology and Engineering Henan University of Science and Technology Luoyang China Beijing Daxing District Integrated Chinese and Western Medicine Hospital Beijing China Hong Sen Hospital Sanya Harbin Medical University Sanya China Beijing Xingchen Wanyou Technology Co. Ltd. Beijing China Institute of Neurological Training and Rehabilitation Medicine of Guangxi Guihai Hospital Fangchenggang China

Objective: To develop a kind self active resistance movement training equipment for cervical spine, so as to restore the dynamic balance of the front and back muscle strength of the cervical spine in order to correct the abnormal physiological radian of the cervical spine, thereby relieving the clinical symptoms. Methods: The air spring with adjustable strength was used to provide the power of resistance active movement, and the neurological training cervical audio-visual synthesis training software was used to automatically guide patients to perform resistance active movement training of the cervical spine. Thirty two patients with cervical spondylosis were enrolled for treatment, and SPSS26 was used to statistically analyze the VAS, Lovett muscle strength, head and neck range of motion and C2-3 vertebral body curvature before and after the treatment. Result: There were significant differences in posterior cervical muscle strength (Lovett), dizziness, shoulder and neck pain (VAS) and C2-3 vertebral curvature before and after training in 32 patients (p˂0.001). Conclusion: The application of neurological training cervical vertebra self rehabilitation training instrument can effectively relieve clinical symptoms, restore head and neck range of motion, improve nape muscle strength, restore the dynamic balance of front and rear cervical muscle strength, and also can correct the abnormal physiological radian of the cervical vertebra.

关键词： Cervical Spondylosis Rehabilitation Equipment Neurological Training Induced Impedance Self Training