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Determination of Fe^(2+)/Fe^(3+)Ratios of Magnetite using Different Methods:A Case Study from the Qimantag Metallogenic Belt

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2135-2147页

作者： yi liwen LI Qiuping LU Anhuai GU Xiangping CHI Guoxiang School of Geographical Sciences Hunan Normal UniversityChangsha 410081China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China School of Earth and Space Sciences Peking UniversityBeijing 100871China Department of Geology University of ReginaReginaSaskatchewan S4S 0A2Canada

Determination of Fe^(2+)/Fe^(3+) ratios from metallogenic belts to explore controlling physical and chemical conditions of rock formation is of great significance.In order to explore magnetite Fe^(2+)/Fe^(3+) ratios of the Qimantag metallogenic belt,part of the Eastern Kunlun orogenic belt in the northeastern margin of the Qinghai–Tibetan plateau,western Central Orogenic Belt of China,and overcome the limitation of the traditional electronic probe,five different measurement methods are proposed and their respective advantages and disadvantages evaluated,with the composition data of the magnetite obtained using electron probe microanalysis(EPMA).The direct oxygen measurement method has a significant impact on the determination results of FeO and Fe2O3,but the accuracy and uniformity of the results are low.The valence method(Flank method)based on the spectral intensity ratio of Lαto Lβfor iron is also unreliable for FeO and Fe_(2)O^(3) measurements because it is difficult to establish a relationship between Lβ/Lα,the spectral intensity ratio,and the Fe^(2+)/Fe^(3+) content ratio.In comparison,the charge difference method,the surplus-oxygen method and the Mössbauer spectrum method are still the most favorable.Mössbauer spectroscopy,with its isomer movement particularly sensitive to the oxidation state of iron,yields results closer to 0.5,which is relatively reliable.Earlier magnetite deposits are located in intrusions or contact zones and formed by magmatic fluids with high Fe2+/Fe3+ratios,whereas later magnetite deposits are farther away from intrusions and have low Fe^(2+)/Fe^(3+) ratios.The transformation mechanism of hematite and magnetite in the Qimantage metallogenic belt is also studied.No large volume changes,such as pore filling and shrinkage fracture,were detected in the metallogenic belt,and the transformation mechanism is more similar to a reoxidation and reduction mechanism.

关键词： iron magnetite direct oxygen measurement flank-charge difference-surplus-oxygen methods Mössbauer spectra Qimantage

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Engineering Photocleavable Protein-decorated Hydrogels to Regulate Cell Adhesion and Migration

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Chemical Research in Chinese Universities 2022年第6期38卷 1512-1517页

作者： LI Tianyi HUANG Yaying LU Chenjing GU liwen CAO yi yiN Sheng Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructureDepartment of PhysicsNanjing UniversityNanjing210093P.R.China Jurong Country Garden School Zhenjiang

Cell adhesion and migration play essential roles in tissue development and maintenance, and abnormal cell migration is involved in life-threatening diseases, including vascular disease, tumor formation, and metastasis. The advances in hydrogel-based 3D cell culture development facilitated the investigation of cell motility behavior, including cell-cell and cell-matrix adhesion and cell migration in a microenvironment more related to in vivo situations. Establishing advanced methods for these in vitro studies is thus necessary. Photo-sensitive proteins show advantages in remote and non-invasive regulation of hydrogels’ properties, and thus are of great potential in regulating 3D cultured cells’ behavior. In the presented study, we engineered photocleavable protein(PhoCl)-decorated hydrogels to regulate cell adhesion and migration of MDA-MB-231. The integrin-binding motif RGD was fused to the PhoCl and was decorated on the hydrogel. After being exposed to light at 405 nm, the PhoCl was cleaved and the RGD motif was released, resulting in detachment of the binding cells. The regulatory effect of the light illumination showed a time-dependent and cell density-dependent manner. Furthermore, the elimination of RGD by patterned light exposure completely suspended the cell migration to the corresponding region, suggesting a controllable regulation of the cell migration direction.

关键词： Cell adhesion Cell migration Photoresponsive protein Hydrogel Photoresponsive hydrogel Photocleavable protein

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Applications of bioinspired approaches and challenges inmedical devices

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Bio-Design and Manufacturing 2021年第1期4卷 146-148页

作者： Huawei Chen yi Zhang liwen Zhang Xilun Ding Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijingChina Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijingChina

Urgent requirements of medical devices Precision medicine has gradually become a development strategy in many countries and attracted worldwide attention in recent years due to the increasing concerns in public health.Although the definition of precision medicine has less or more difference from the viewpoints of different fields,the demands on the properties of medical devices or medical materials involving biocompatibility and anti-thrombosis are gradually growingmuch more diverse and much more urgent than ever[1].This trend brings up many new research topics about materials,mechanical systems and sensors to develop advanced medical devices.How to design and on-demand fabricate the bio-materials,bio-interface and bio-systems to meet the urgent demands of medical devices is still a challenge for us.

关键词： interface urgent viewpoint

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Re-Os Isotopic Age of Molybdenite of the Jingren Deposit and its Mineralogical Significance of Magnetite,Pyrite and Chalcopyrite

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1236-1248页

作者： CAO Li yi liwen DAI Wei XIE Binggeng LI Xiaoqing LU Anhuai GU Xiangping College of Geographic Sciences Hunan Normal UniversityChangsha 410081China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Central South University) Ministry of EducationChangsha 410083China The Third of Qinghai Geological and Mineral Exploration Institute Xining 810012China College of Geosciences and Info-Physics Central South UniversityChangsha 410083China

The Jingren deposit is part of the Qimantage metallogenic belt within the eastern Kunlun orogenic belt,the largest metallogenic belt in Qinghai Province,northwestern China.Exploration data show that the metal resources of the Jingren deposit are greater than 93000 t in a mining area of 76.15 km2,which indicates significant exploration potential in the near future.Three W–E-trending faults,F1-3,dominate the extension of the mineralization zone,which consists of chalcopyrite,pyrite,magnetite,galena,sphalerite,and molybdenite as well as bismuth-bearing minerals.The deposit contains a large amount of late Triassic intrusive rocks,however,previous research did not reach a consensus on the timing or the origin of the mineralization owing to a lack of geochronological data and poor exposure conditions.In the present study,Re-Os isotopic dating from six molybdenite samples collected from a borehole of the granodiorite in the Jingren deposit using negative thermal ionization mass spectrometry(NTIMS)showed 187 Re and 187 Os concentrations of 0.26–4.40 ppm and 1.03–16.46 ppb,respectively,with an initial 187 Os/188 Os value of 0.06±0.19.This proves that the Jingren deposit has a metallogenic age of(225±4)Ma and is the product of united mineralization of the Qimantage metallogenic belt and that the Jingren deposit might actually be an Indosinian metallogeny.In addition,the Re content of these samples,at 0.42 ppm to 7.00 ppm shows that the mineralization was derived mainly from a crustal source.Furthermore,electron probe microanalysis(EPMA)conducted on chalcopyrite obtained from 22 metallic mineral samples revealed(Fe+Cu)/S ratios of 1.801–1.947 with an average of 1.852,which is lower than the ideal value(1.875).Besides,the main ore body formed in a relatively higher temperature environment than the surrounding rocks in the Jingren deposit.These data indicate that the Jingren deposit formed in a metallogenic environment at lower temperature.Moreover,according to the TiO_(2)-Al_(2)O_(3)-(MgO+MnO)and TiO_(2)-Al_(2)O_(3)-MgO gene

关键词： mineralogy Re-Os isotopic dating molybdenite skarn Indosinian Jingren deposit Qimantage metallogenic belt

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Bioinspired Unidirectional Liquid Transport Micro-nano Structures:A Review

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Journal of Bionic Engineering 2021年第1期18卷 1-29页

作者： liwen Zhang Guang Liu Huawei Chen Xiaolin Liu Tong Ran yi Zhang Yang Gan Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China

Unidirectional liquid transport without any need of external energy has drawn worldwide attention for its potential applications in various fields such as microfluidics,biomedicine and mechanical engineering.In nature,numerous creatures have evolved such extraordinary unidirectional liquid transport ability such as spider sik,Sarracenia's trichomes,and Nepenthes alata's peristome,etc.This review summarizes the current progresses of natural unidirectional liquid transport on 1-Dimensional(1D)linear structure and 2-Dimensional(2D)surface stucture.The driving force of unidirectional liquid transport which is determined by unique structure exist distinct differences in physics.The fundamental understanding of 1D and 2D unidirectionaliquid transport especially about hierarchical structural characteristics and their transport mechanism were concentrated,and various bioinspired fabrication methods are also introduced.The applications of bioinspired directional liquid transport are demonstrated especially in fields of microfluidies,biomedical devices and anti-icing surfaces.With newly developed smart materials,various liquid transport regulation strategies are also summarized for the control of transport speed,direction guiding,etc.Finally,we provide new insights and future perspectives of the directional transport materials.

关键词： bioinspiration unidirectional liquid transport microfluidics smart materials Nepenthes alata Sarracenia trichomes

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ZrO_(2)高硬材料超声振动激光磨削孔加工参数优化

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山西冶金 2023年第7期46卷 45-46,49页

作者：易礼文泉州市高级技工学校机械教研组福建泉州362000

ZrO_(2)高硬材料一般均采用各种火法冶金与湿化学法相结合工艺制备,其极高的硬度给机加工带来极大的难度。为了提高孔径出孔端面质量,开展了超声振动激光磨削孔加工参数优化的实验研究。通过综合分析孔出口端面崩边区域范围和理想孔截... 详细信息

ZrO_(2)高硬材料一般均采用各种火法冶金与湿化学法相结合工艺制备,其极高的硬度给机加工带来极大的难度。为了提高孔径出孔端面质量,开展了超声振动激光磨削孔加工参数优化的实验研究。通过综合分析孔出口端面崩边区域范围和理想孔截面的面积之比来评判孔出口的质量水平(Hd值)。研究结果表明:提高进给速度后,Hd值先降低后升高;随着振幅升高,Hd值先降低后升高;Hd值的降低反映出孔出口端面质量更优,因此需尽可能地设置更低的Hd值。最终确定最佳激光磨削工艺参数:进给速度0.5~0.7 mm/min,振幅7~9μm。该研究对提高高硬材料的激光磨削质量具有很好的指导意义。

关键词：超声激光磨削孔崩边崩边抑制质量控制

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The biology,function,and applications of exosomes in cancer

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Acta Pharmaceutica Sinica B 2021年第9期11卷 2783-2797页

作者： Jinyi Liu liwen Ren Sha Li Wan Li Xiangjin Zheng yihui Yang Weiqi Fu Jie yi Jinhua Wang Guanhua Du The State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing 100050China Key Laboratory of Drug Target Research and Drug Screen Institute of Materia MedicaChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100050China Department of Clinical Laboratory Peking Union Medical College HospitalBeijing 100730China

Exosomes are cell-derived nano vesicles with diameters from 30 to 150 nm,released upon fusion of multi vesicular bodies with the cell surface.They can transport nucleic acids,proteins,and lipids for intercellular communication and activate signaling pathways in target cells.In cancers,exosomes may participate in growth and metastasis of tumors by regulating the immune response,blocking the epithelial-mesenchymal transition,and promoting angiogenesis.They are also involved in the development of resistance to chemotherapeutic drugs.Exosomes in liquid biopsies can be used as non-invasive biomarkers for early detection and diagnosis of cancers.Because of their amphipathic structure,exosomes are natural drug delivery vehicles for cancer therapy.

关键词： Exosomes Tumor immunity Tumor metastasis Drug resistance Biomarkers Drug delivery

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Clinical significance of germline copy number variation in susceptibility of human diseases

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Journal of Genetics and Genomics 2018年第1期45卷 3-12页

作者： liwen Hu Xinyue Yao Hairong Huang Zhong Guo Xi Cheng Yang Xu yi Shen Biao Xu Demin Li Department of Cardiothoracic Surgery Jinling Hospital School of Clinical Medicine Nanjing University Institute of Laboratory Medicine Jinling Hospital School of Clinical Medicine Nanjing University

Germline copy number variation （CNV） is considered to be an important form of human genetic poly- morphisms. Previous studies have identified amounts of CNVs in human genome by advanced technologies, such as comparative genomic hybridization, single nucleotide genotyping, and high-throughput sequencing. CNV is speculated to be derived from multiple mechanisms, such as nonallelic homologous recombination （NAHR） and nonhomologous end-joining （NHEJ）. CNVs cover a much larger genome scale than single nucleotide polymorphisms （SNPs）, and may alter gene expression levels by means of gene dosage, gene fusion, gene disruption, and long-range regulation effects, thus affecting individual phenotypes and playing crucial roles in human pathogenesis. The number of studies linking CNVs with common complex diseases has increased dramatically in recent years. Here, we provide a comprehensive review of the current understanding ofgermline CNVs, and summarize the association of germline CNVs with the susceptibility to a wide variety of human diseases that were identified in recent years. We also propose potential issues that should be addressed in future studies.

关键词： Copy number variation Susceptibility Risk Cancer Neuropsychological disorders

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Green tea polyphenols supplementation alters immunometabolism and oxidative stress in dairy cows with hyperketonemia

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Animal Nutrition 2021年第1期7卷 206-215页

作者： Yanfen Ma ying Feng liwen Song Muyang Li Hongyu Dai Hua Bao Guijie Zhang Lei Zhao Chunhua Zhang Jing yi Yusheng Liang School of Agriculture Ningxia UniversityYinchuan 750021China Institute of Animal Nutrition and Feed Inner Mongolia Academy of Agriculture and Animal Husbandry SciencesHohhot 010031China College of Food Engineering&Biotechnology Tianjin University of Science&TechnologyTianjin 300457China College of Animal Science and Veterinary Medicine Heilongjiang Bayi Agricultural UniversityDaqing 163316China College of Veterinary Medicine Nanjing Agricultural UniversityNanjing 210095China Department of Animal Sciences and Division of Nutritional Sciences University of IllinoisUrbana 61801USA

Peripartal cows often experience negative energy balance,and are therefore prone to suffering from metabolic diseases such as hyperketonemia,which causes financial losses in dairy farms.This study aimed to investigate the effect of green tea polyphenol(GTP)supplementation during the periparturient period on production performance,oxidative stress and immunometabolism in dairy cows with hyperketonemia.One hundred Holstein cows were assigned to GTP(0.2 g/kg DM;n=50)or control(without GTP;n=50)group based on body weight,previous milk yield,and parity on d 15 before expected parturition.Subsequently,10 cows with hyperketonemia were selected from each group,according to bloodβ-hydroxybutyric acid(BHBA)concentration between 1.2 and 2.9 mmol/L from 2 to 3 d postpartum.All cows were fed a close-up diet and a lactation diet with or without GTP supply from 15 d prepartum until 30 d postpartum.Milk and blood samples were obtained from 20 cows selected with hyperketonemia on 10,20,and 30 d postpartum.Compared with control cows,greater milk yield and lower somatic cell count were observed in GTP cows.The GTP group had lower concentrations of BHBA,free fatty acids,cholesterol,triglyceride,reactive oxygen species,malondialdehyde,and hydrogen peroxide,greater concentrations of glucose,lower activities of aspartate aminotransferase,alanine aminotransferase,and glutamyl transpeptidase,alongside greater ac-tivities of superoxide dismutase,glutathione peroxidase,and total antioxidant capacity.Additionally,GTP supplementation up-regulated concentrations of interleukin-6 and interleukin-10,but down-regulated concentrations of tumor necrosis factor-α,interleukin-1β,interleukin-2,interleukin-8,and interferon-γin plasma.Greater concentrations of plasma immunoglobulin G were also detected in the GTP group.Overall,the data suggested that GTP supplementation from 15 d prepartum to 30 d postpartum improved the milk yield and health status in cows with hvoerketonemia during early lactation.

关键词： Green tea polyphenol Hyperketonemia Peripartal period Dairy cow

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METTL9 mediated N1-histidine methylation of zinc transporters is required for tumor growth

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Protein & Cell 2021年第12期12卷 965-970页

作者： Mengyue Lv Dan Cao liwen Zhang Chi Hu Shukai Li Panrui Zhang Lianbang Zhu Xiao yi Chaoliang Li Alin Yang Zhentao Yang yi Zhu Kaiguang Zhang Wen Pan Department of Gastroenterology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at Microscale the CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Basic Medical SciencesDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Structural Biology of Zhejiang Province School of Life SciencesWestlake UniversityHangzhou 310024China Institute of Basic Medical Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Dear Editor,Histidine methylation has been known for many years(Searle and Westall,1951),but only a few proteins carrying such modifications have been studied(Webb et al.,2010;Al-Hadid et al.,2014;Kwiatkowski et al.,2... 详细信息

关键词： al. Searle tumor

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