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Science with the 2.5-meter Wide Field Survey Telescope(WFST) 被引量:6
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作者 Tinggui Wang Guilin Liu +59 位作者 Zhenyi Cai Jinjun Geng Min Fang Haoning He Ji-an Jiang Ning Jiang Xu Kong Bin Li Ye Li Wentao Luo Zhizheng Pan Xuefeng Wu Ji Yang Jiming Yu Xianzhong Zheng Qingfeng Zhu yi-fu Cai yuanyuan Chen Zhiwei Chen Zigao Dai Lulu Fan yizhong Fan Wenjuan Fang Zhicheng He Lei Hu Maokai Hu Zhiping Jin Zhibo Jiang Guoliang Li Fan Li Xuzhi Li Runduo Liang Zheyu Lin Qingzhong Liu Wenhao Liu Zhengyan Liu Wei Liu Yao Liu Zheng Lou Han Qu Zhenfeng Sheng Jianchun Shi yiping Shu Zhenbo Su Tianrui Sun Hongchi Wang Huiyuan Wang Jian Wang Junxian Wang Daming Wei Junjie Wei Yongquan Xue Jingzhi Yan Chao Yang Ye yuan Yefei yuan Hongxin Zhang Miaomiao Zhang Haibin Zhao Wen Zhao 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2023年第10期155-202,共48页
The Wide Field Survey Telescope(WFST) is a dedicated photometric surveying facility being built jointly by University of Science and Technology of China(USTC) and the Purple Mountain Observatory(PMO). It is equipped w... The Wide Field Survey Telescope(WFST) is a dedicated photometric surveying facility being built jointly by University of Science and Technology of China(USTC) and the Purple Mountain Observatory(PMO). It is equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic CCD camera with 0.73 gigapixels on the primary focal plane for highquality image capture over a 6.5-square-degree field of view. The installation of WFST near the summit of Saishiteng mountain in the Lenghu region is scheduled in summer of 2023, and the operation is planned to start three months later. WFST will scan the northern sky in four optical bands(u, g, r and i) at cadences from hourly/daily in the deep high-cadence survey(DHS) program, to semi-weekly in the wide field survey(WFS) program. During a photometric night, a nominal 30 s exposure in the WFS program will reach a depth of 22.27, 23.32, 22.84, and 22.31(AB magnitudes) in these four bands, respectively, allowing for the detection of a tremendous amount of transients in the low-z universe and a systematic investigation of the variability of Galactic and extragalactic objects. In the DHS program, intranight 90 s exposures as deep as 23(u) and 24 mag(g), in combination with target of opportunity follow-ups, will provide a unique opportunity to explore energetic transients in demand for high sensitivities, including the electromagnetic counterparts of gravitational wave events, supernovae within a few hours of their explosions,tidal disruption events and fast, luminous optical transients even beyond redshift of unity. In addition, the final 6-year co-added images, anticipated to reach g■25.8 mag in WFS or 1.5 mags deeper in DHS, will be of fundamental importance to general Galactic and extragalactic science. The highly uniform legacy surveys of WFST will serve as an indispensable complement to those of the Vera C. Rubin Observatory's Legacy Survey of Space and Time(LSST) that monitors the southern sky. 展开更多
关键词 optical telescope time domain astronomy photometric survey SUPERNOVAE multi-messenger events tidal disruption event
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Human-like adrenal features in Chinese tree shrews revealed by multi-omics analysis of adrenal cell populations and steroid synthesis
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作者 Jing-Hang Jiang yi-fu Wang +14 位作者 Jie Zheng yi-Ming Lei Zhong-yuan Chen yi Guo Ya-Jie Guo Bing-Qian Guo Yu-Fang Lv Hong-Hong Wang Juan-Juan Xie yi-Xuan Liu Ting-Wei Jin Bi-Qi Li Xiao-Shu Zhu Yong-Hua Jiang Zeng-Nan Mo 《Zoological Research》 SCIE CSCD 2024年第3期617-632,共16页
The Chinese tree shrew(Tupaia belangeri chinensis)has emerged as a promising model for investigating adrenal steroid synthesis,but it is unclear whether the same cells produce steroid hormones and whether their produc... The Chinese tree shrew(Tupaia belangeri chinensis)has emerged as a promising model for investigating adrenal steroid synthesis,but it is unclear whether the same cells produce steroid hormones and whether their production is regulated in the same way as in humans.Here,we comprehensively mapped the cell types and pathways of steroid metabolism in the adrenal gland of Chinese tree shrews using single-cell RNA sequencing,spatial transcriptome analysis,mass spectrometry,and immunohistochemistry.We compared the transcriptomes of various adrenal cell types across tree shrews,humans,macaques,and mice.Results showed that tree shrew adrenal glands expressed many of the same key enzymes for steroid synthesis as humans,including CYP11B2,CYP11B1,CYB5A,and CHGA.Biochemical analysis confirmed the production of aldosterone,cortisol,and dehydroepiandrosterone but not dehydroepiandrosterone sulfate in the tree shrew adrenal glands.Furthermore,genes in adrenal cell types in tree shrews were correlated with genetic risk factors for polycystic ovary syndrome,primary aldosteronism,hypertension,and related disorders in humans based on genome-wide association studies.Overall,this study suggests that the adrenal glands of Chinese tree shrews may consist of closely related cell populations with functional similarity to those of the human adrenal gland.Our comprehensive results(publicly available at http://gxmujyzmolab.cn:16245/scAGMap/)should facilitate the advancement of this animal model for the investigation of adrenal gland disorders. 展开更多
关键词 Tree shrew Adrenal gland DEHYDROEPIANDROSTERONE Genome-wide association studies Disease model
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PRaG 3.0 therapy for human epidermal growth factor receptor 2-positive metastatic pancreatic ductal adenocarcinoma:A case report 被引量:1
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作者 Yue-Hong Kong Mei-Ling Xu +10 位作者 Jun-Jun Zhang Guang-Qiang Chen Zhi-Hui Hong Hong Zhang Xiao-Xiao Dai yi-fu Ma Xiang-Rong Zhao Chen-Yang Zhang Rong-Zheng Chen Peng-Fei Xing Li-yuan Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1237-1249,共13页
BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly fatal disease with limited effective treatment especially after first-line chemotherapy.The human epidermal growth factor receptor 2(HER-2)immunohistochemis... BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly fatal disease with limited effective treatment especially after first-line chemotherapy.The human epidermal growth factor receptor 2(HER-2)immunohistochemistry(IHC)positive is associated with more aggressive clinical behavior and shorter overall survival in PDAC.CASE SUMMARY We present a case of multiple metastatic PDAC with IHC mismatch repair proficient but HER-2 IHC weakly positive at diagnosis that didn’t have tumor regression after first-line nab-paclitaxel plus gemcitabine and PD-1 inhibitor treatment.A novel combination therapy PRaG 3.0 of RC48(HER2-antibody-drug conjugate),radio-therapy,PD-1 inhibitor,granulocyte-macrophage colony-stimulating factor and interleukin-2 was then applied as second-line therapy and the patient had confirmed good partial response with progress-free-survival of 6.5 months and overall survival of 14.2 month.She had not developed any grade 2 or above treatment-related adverse events at any point.Percentage of peripheral CD8^(+) Temra and CD4^(+) Temra were increased during first two activation cycles of PRaG 3.0 treatment containing radiotherapy but deceased to the baseline during the maintenance cycles containing no radiotherapy.CONCLUSION PRaG 3.0 might be a novel strategy for HER2-positive metastatic PDAC patients who failed from previous first-line approach and even PD-1 immunotherapy but needs more data in prospective trials. 展开更多
关键词 Pancreatic ductal adenocarcinoma PRaG 3.0 therapy Human epidermal growth factor receptor 2 Novel combination therapy Case report
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分布式制氢技术在加氢站中的应用进展 被引量:2
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作者 魏民 常胜 +7 位作者 李东 刘奇峰 甘一夫 王施媛 石秦川 方涛 杨福胜 王斌 《化工机械》 CAS 2023年第3期281-289,共9页
跟踪了国内外加氢站的发展现状,总结了各类加氢站的技术路线、原理、优势以及应用局限,估算了天然气重整制氢、甲醇重整制氢、碱性电解水制氢和有机液态载体(LOHC)制氢4种分布式制氢方式的成本,并预测了未来我国加氢站的发展趋势。
关键词 分布式制氢技术 加氢站 LOHC 氮杂环芳烃 经济性分析
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Targeted metabolomics study of fatty-acid metabolism in lean metabolic-associated fatty liver disease patients
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作者 Pei-Qi Sun yi-fu yuan +4 位作者 Qin Cao Xiao-Yan Chen yuan-Ye Jiang Wen-Min Dong Li-Li Guo 《World Journal of Gastroenterology》 SCIE CAS 2024年第27期3290-3303,共14页
BACKGROUND The annual incidence of metabolic-associated fatty liver disease(MAFLD)in China has been increasing and is often overlooked owing to its insidious charac-teristics.Approximately 50%of the patients have a no... BACKGROUND The annual incidence of metabolic-associated fatty liver disease(MAFLD)in China has been increasing and is often overlooked owing to its insidious charac-teristics.Approximately 50%of the patients have a normal weight or are not obese.They are said to have lean-type MAFLD,and few studies of such patients are available.Because MAFLD is associated with abnormal lipid metabolism,lipid-targeted metabolomics was used in this study to provide experimental evidence for early diagnosis and pathogenesis.MAFLD and analyze metabolic pathways.UPLC-Q-Orbitrap/MS content determination was used to determine serum palmitic acid(PA),oleic acid(OA),linoleic acid(LA),and arachidonic acid(AA)levels in lean-type MAFLD patients.RESULTS Urea nitrogen and uric acid levels were higher in lean-type MAFLD patients than in healthy individuals(P<0.05).Alanine transaminase and cholinesterase levels were higher in lean-type MAFLD patients than in healthy indi-viduals(P<0.01).The expression of high-density lipoprotein and apolipoprotein A-1 were lower in lean-type MAFLD patients than in healthy individuals(P<0.05)and the expression of triglycerides and fasting blood glucose were increased(P<0.01).A total of 65 biomarkers that affected the synthesis and metabolism of fatty acids were found with P<0.05 and variable importance in projection>1.The levels of PA,OA,LA,and AA were significantly increased compared with healthy individuals.CONCLUSION The metabolic profiles of lean-type MAFLD patients and healthy participants differed significantly,yielding 65 identified biomarkers.PA,OA,LA,and AA exhibited the most significant changes,offering valuable clinical guidance for prevention and treatment of lean-type MAFLD. 展开更多
关键词 Lean-type metabolic-associated fatty liver disease Targeted serum metabolomics Fatty acids Principal component analysis Orthogonal partial least squares-discriminant analysis
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成都某填埋场反渗透浓缩液浸没燃烧蒸发技术应用
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作者 张聪慧 王凯 +7 位作者 刘一夫 姚远 王候兵 石欢 吉龙标 李强 陈玉婷 李晓旭 《中国给水排水》 CAS CSCD 北大核心 2024年第14期119-125,共7页
反渗透浓缩液作为膜达标产水后富集物,其溶解性总固体和总氮含量高,基本不具备生物处理条件,一直是渗滤液处理的难点,目前国内的处理方式主要为回喷/回灌和蒸发。成都某填埋场浓缩液处理系统采用浸没燃烧蒸发工艺全量处理反渗透浓缩液,... 反渗透浓缩液作为膜达标产水后富集物,其溶解性总固体和总氮含量高,基本不具备生物处理条件,一直是渗滤液处理的难点,目前国内的处理方式主要为回喷/回灌和蒸发。成都某填埋场浓缩液处理系统采用浸没燃烧蒸发工艺全量处理反渗透浓缩液,利用高温烟气与反渗透浓缩液直接换热缓解系统结垢,通过控制pH和温度等反应条件,解决盐分在渗滤液系统内积累的问题,促进系统的稳定良性运转,蒸发产生的蒸汽冷凝后产水水质达标,另设置反渗透系统作进一步保障。该项目出水水质满足《生活垃圾填埋场污染控制标准》(GB16889-2008)的表2标准。采用厌氧沼气和天然气作为能源,整体自动化程度高,运行稳定,出水水质达标。以产水量计,电耗<45 kW·h/m^(3)、天然气消耗量约82m^(3)/m^(3). 展开更多
关键词 垃圾填埋场 垃圾焚烧厂 反渗透浓缩液 溶解性总固体 总氮 浸没燃烧蒸发 盐分积累 全量处理
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堆肥对重金属污染的水稻根际土壤细菌群落的剂量依赖性影响
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作者 熊婷 崔佳文 +7 位作者 蒋龙波 王晗 黎一夫 苏长青 陈艳容 曹旭洋 袁兴中 易国栋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第2期642-652,共11页
在复合重金属污染的水稻土壤中分别添加1%、5%和10%(质量分数)的堆肥,150 d后观察土壤微生物群落的结构和组成变化。研究发现,堆肥对根际细菌群落的影响表现出剂量依赖效应。低等(1%)和中等(5%)堆肥添加量对根际细菌群落结构的影响比对... 在复合重金属污染的水稻土壤中分别添加1%、5%和10%(质量分数)的堆肥,150 d后观察土壤微生物群落的结构和组成变化。研究发现,堆肥对根际细菌群落的影响表现出剂量依赖效应。低等(1%)和中等(5%)堆肥添加量对根际细菌群落结构的影响比对非根际细菌群落的影响更大。根际土壤细菌多样性在添加堆肥后明显低于非根际土壤细菌多样性。冗余分析(RDA)结果表明,根际和非根际细菌群落对土壤理化性质(如p H、Pb、Cd和Cu含量)变化的响应不同,可能是根际和非根际细菌群落差异的原因之一。因此,在农业管理中应该考虑堆肥的施加对根际微生物的影响。 展开更多
关键词 根际土壤 微生物群落 有机改良剂 重金属
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CAV3 mediates IMGU and NIMGU in skeletal muscle and cardiac myocytes
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作者 ZHOU Cai-xia LV Qian +5 位作者 BU Xiao-yang TIAN yi-fu XIAN Jing HUANG yuan-heng YANG Li-hui HUANG Qin 《Journal of Hainan Medical University》 CAS 2023年第8期1-7,共7页
Objective:To observe whether CAV3 is involved in the physiological process of IMGU and NIMGU.Down-regulation of caveolin-3(CAV3)protein expression by small interference RNAs(iRNA)has been studied.Insulin-mediated gluc... Objective:To observe whether CAV3 is involved in the physiological process of IMGU and NIMGU.Down-regulation of caveolin-3(CAV3)protein expression by small interference RNAs(iRNA)has been studied.Insulin-mediated glucose uptake(IMGU)is critical in skeletal muscle and cardiac myocytes,but non-insulin-mediated glucose uptake(NIMGU)should not be neglected.Methods:CAV3 siRNAs were designed and transfected in C2C12 cells and H9c2 cells in skeletal muscle and cardiac muscle,respectively,and C2C12 and H9c2 cells were cultured in DMEM medium with and without insulin,respectively.Glucose transporter 4(GLUT4)protein expression was detected by Western blot,and the glucose uptake rate of cells was measured by biochemical kit.Results:Transfection with CAV3 siRNA successfully down-regulated CAV3 protein expression in C2C12 and H9c2 cells.In the absence of insulin stimulation,GLUT4 expression was decreased(P<0.01)and glucose uptake was reduced(P<0.05)after 48 h of transfection in C2C12 cells,and GLUT4 expression was decreased(P<0.05)and glucose uptake was reduced(P<0.01)after 48 h of transfection in H9c2 cells.In the presence of insulin stimulation,GLUT4 expression was decreased(P<0.01)and glucose uptake was reduced(P<0.01)after 48 h of transfection in C2C12 cells,and the downregulation of GLUT4 was not statistically significant and glucose uptake was reduced(P<0.01)after 48 hours of transfection in H9c2 cells.Conclusion:Two different states,IMGU and NIMGU,exist in C2C12 cells and H9c2 cells.Both in the quiet state stimulated by insulin as well as in the absence of insulin stimulation,the cellular uptake of glucose is affected by GLUT4 changes regulated by CAV3. 展开更多
关键词 Caveolin-3 GLUT4 C2C12 cells H9c2 cells Glucose uptake
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Microstructures and properties of Cu-Cr-W composite coatings fabricated by surface mechanical alloying technique 被引量:3
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作者 Jia-Ping Zhang Xiao-Mei Feng +2 位作者 yi-fu Shen Cheng Chen Cui-yuan Duan 《Rare Metals》 SCIE EI CAS CSCD 2022年第12期4248-4256,共9页
Cu-Cr-W composite coatings were prepared by mechanical alloying(MA)method using different powder ratios,rotational speeds and milling time.The micro structures and chemical compositions of as-synthesized coatings were... Cu-Cr-W composite coatings were prepared by mechanical alloying(MA)method using different powder ratios,rotational speeds and milling time.The micro structures and chemical compositions of as-synthesized coatings were analyzed by scanning electron microscopy(SEM)and energy-dispersive spectroscopy(EDS).Phases of ball-milled powders were identified by X-ray diffraction(XRD).The results indicate that the coating fabricated with powder ratio of 40 wt%Cu-Cr-W has better surface and cross-sectional microstructures and higher microhardness.The comparisons of cross-sectional micro structures of the coatings fabricated at different rotational speeds suggest that rotational speed of 300 r·min-1is the optimal for fabrication the coating,and the optimal milling time for the formation of coating is 7 h.The results of microhardness test show that the hardness of the substrate is largely improved because of the as-fabricated coatings.The results of the friction and wear tests indicate that the wear resistance of the copper substrate is improved after the deposition of Cu-Cr-W coating on it.The coating fabricated for 7 h exhibits the lowest friction coefficient,indicating its favorable friction and wear resistance.The formation mechanism of the coating was elucidated.According to the investigations in this work,the Cu-Cr-W coating fabricated by MA method is considered to be effective to reinforce the copper substrate. 展开更多
关键词 Mechanical alloying Composite coating Powder ratio Processing parameter
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CAV3介导骨骼肌和心肌细胞的IMGU和NIMGU
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作者 周彩霞 吕倩 +5 位作者 卜晓阳 田一夫 冼晶 黄媛恒 杨立会 黄勤 《海南医学院学报》 CAS 2023年第8期561-567,共7页
目的:胰岛素介导的葡萄糖摄取(insulin-mediated glucose uptake,IMGU)在骨骼肌和心肌细胞至关重要,但非胰岛素介导的葡萄糖摄取(non-insulin-mediated glucose uptake,NIMGU)也不容忽视。本文通过siRNA(small interference RNA, siRNA... 目的:胰岛素介导的葡萄糖摄取(insulin-mediated glucose uptake,IMGU)在骨骼肌和心肌细胞至关重要,但非胰岛素介导的葡萄糖摄取(non-insulin-mediated glucose uptake,NIMGU)也不容忽视。本文通过siRNA(small interference RNA, siRNA)下调微囊蛋白-3(caveolin-3, CAV3)蛋白表达,观察CAV3是否参与IMGU及NIMGU的生理过程。方法:分别设计合成针对骨骼肌C2C12细胞和心肌H9c2细胞的CAV3 siRNA并转染,C2C12细胞和H9c2细胞分别在有胰岛素和无胰岛素的DMEM培养基中培养,采用激光共聚焦显微镜观测细胞转染效果,Western blot检测CAV3、葡萄糖转运体4(Glucose transporter 4,GLUT4)蛋白表达,生化试剂盒检测细胞的葡萄糖摄取率。结果:转染CAV3 siRNA后成功下调C2C12和H9c2细胞CAV3蛋白的表达。在无胰岛素刺激时,C2C12细胞转染48 h后,GLUT4表达降低(P<0.01),葡萄糖摄取减少(P<0.05),H9c2细胞转染48 h后,GLUT4表达降低(P<0.05),葡萄糖摄取减少(P<0.01)。有胰岛素刺激时,C2C12细胞转染48 h后,GLUT4表达降低(P<0.01),葡萄糖摄取减少(P<0.01),H9c2细胞转染48 h后,GLUT4的下调无统计学意义,葡萄糖摄取减少(P<0.01)。结论:C2C12细胞和H9c2细胞存在IMGU和NIMGU的这两种不同状态。在胰岛素刺激的以及无胰岛素刺激的安静状态下,都通过CAV3调节GLUT4变化而影响细胞摄取葡萄糖。 展开更多
关键词 Caveolin-3 GLUT4 C2C12细胞 H9C2细胞 葡萄糖摄取
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四川理塘脚根玛锡锌矿床成因与成矿模式
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作者 曾毅夫 梁鹏飞 +5 位作者 徐勇 谢伟 曾杰 袁宵 杨魁 赵久军 《四川地质学报》 2021年第4期604-608,共5页
脚根玛锡锌矿床位于昌多阔-格聂Sn-Ag-Pb-Zn-Cu构造岩浆成矿带,燕山晚期绒依措黑云母二长花岗岩体北东缘,矿体赋存于中三叠世列衣组组变质砂岩夹板岩的北北西向构造破碎带中,初步圈定锡锌多金属矿带6条,脉状、透镜状锡锌矿体20个。自岩... 脚根玛锡锌矿床位于昌多阔-格聂Sn-Ag-Pb-Zn-Cu构造岩浆成矿带,燕山晚期绒依措黑云母二长花岗岩体北东缘,矿体赋存于中三叠世列衣组组变质砂岩夹板岩的北北西向构造破碎带中,初步圈定锡锌多金属矿带6条,脉状、透镜状锡锌矿体20个。自岩体方向由内向外,围岩蚀变由近外接触带的角岩化、矽卡岩化过渡为远外接触带的硅化、碳酸盐化、绢云母化、绿泥石化;主成矿元素出现Sn→SnZn→PbZnAg组合分带趋势。矿床形成大致可划分为矽卡岩成矿期、石英硫化物成矿期和表生期,矿物生成顺序为:锡石→黄铁矿-磁黄铁矿→(铁)闪锌矿→方铅矿→黄铜矿。矿床成因为岩浆热液型。 展开更多
关键词 锡锌矿 岩浆热液型 成矿模式 四川理塘脚根玛
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应用单分子触发式级联指数恒温扩增技术检测长链非编码RNA方法的建立
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作者 张斌 李增健 +2 位作者 关一夫 袁莹 李硕 《解剖科学进展》 2020年第4期454-457,共4页
目的建立一种利用核酸恒温指数扩增技术特异性检测长链RNA的高灵敏度检测方法。方法利用恒温指数扩增(EXPAR)反应对所建立的方法进行反应条件的优化,并对该方法的通用性、特异性和灵敏度进行了系统分析。结果单分子触发反应产物可以作... 目的建立一种利用核酸恒温指数扩增技术特异性检测长链RNA的高灵敏度检测方法。方法利用恒温指数扩增(EXPAR)反应对所建立的方法进行反应条件的优化,并对该方法的通用性、特异性和灵敏度进行了系统分析。结果单分子触发反应产物可以作为引物触发指数恒温扩增;柔性引物可以提高检测特异性,柔性臂长7nt;单分子触发式级联指数恒温扩增技术能够有效检测出待检样品浓度在10fmol/L^100pmol/L范围内的靶标RNA,线性响应良好(R 2=0.955)。结论单分子触发级联式恒温指数扩增技术可以快速、准确检测长链RNA。 展开更多
关键词 长链RNA 恒温指数扩增 单分子触发式级联反应
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云南大理苍山保护区植被覆盖度动态变化遥感监测与分析 被引量:14
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作者 王一富 袁磊 《科学技术与工程》 北大核心 2020年第8期2997-3002,共6页
大理苍山物种多样性丰富但生态系统相对脆弱,评估苍山植被覆盖度为改善苍山生态环境和物种多样性具有重要意义。利用ENVI遥感软件对大理苍山自然保护区的4期遥感图像进行处理,提取归一化植被指数(normalized difference vegetation inde... 大理苍山物种多样性丰富但生态系统相对脆弱,评估苍山植被覆盖度为改善苍山生态环境和物种多样性具有重要意义。利用ENVI遥感软件对大理苍山自然保护区的4期遥感图像进行处理,提取归一化植被指数(normalized difference vegetation index,NDVI),利用像素二分模型对大理苍山自然保护区的植被覆盖度进行估算,对植被覆盖度的变化原因进行综合分析。结果表明:2001—2005年植被覆盖度从0.32上升到0.38,上升了0.06;2005—2009年植被覆盖度由0.38下降到0.35,下降了0.03;2009—2011年,植被覆盖度由0.35上升到0.45,上升了0.1。可见综合分析植被覆盖度的年际变化对大理苍山的植被保护和维护生物多样性具有重要的应用参考价值。 展开更多
关键词 遥感监测 归一化植被指数(NDVI) 植被覆盖度 像元二分模型
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脉冲星计时阵列观测的随机背景信号对标量诱导引力波的限制 被引量:3
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作者 蔡一夫 何鑫宸 +2 位作者 马潇汉 鄢盛丰 袁官文 《Science Bulletin》 SCIE EI CAS CSCD 2023年第23期2929-2935,M0004,共8页
最近,NANOGrav、PPTA、EPTA和CPTA合作组各自独立报告了关于随机引力波背景的观测证据.尽管根据观测推断的引力波背景(幅度、频谱)与超大质量双黑洞并合的预言相一致,但这一观测也为搜寻宇宙早期的新物理现象提供了新的窗口.本文探讨了... 最近,NANOGrav、PPTA、EPTA和CPTA合作组各自独立报告了关于随机引力波背景的观测证据.尽管根据观测推断的引力波背景(幅度、频谱)与超大质量双黑洞并合的预言相一致,但这一观测也为搜寻宇宙早期的新物理现象提供了新的窗口.本文探讨了用早期宇宙中的标量诱导引力波来解释这一信号的可能性.作者采用参数化的拐折幂律谱作为随机引力波背景能谱的普适性描述,利用NANOGrav、PPTA和EPTA的新数据和贝叶斯推断的方法进行研究.本研究结果可以约束诱导引力波能谱的相关参数,并进一步对可能在早期宇宙中产生原初黑洞的各种暴胀模型给出限制,这些模型有望在未来的空间引力波观测实验中得到检验. 展开更多
关键词 Pulsar timing array observation Bayesian inference Stochastic gravitational wave background Induced gravitational waves Early universe
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有氧运动干预非酒精性脂肪性肝病的血清代谢组学研究
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作者 袁乙富 杜晟楠 +2 位作者 张思敏 曹勤 蒋元烨 《肝脏》 2024年第5期571-575,618,共6页
目的探讨有氧运动干预4周前后非酒精性脂肪肝病(NAFLD)患者临床特征及血清代谢产物变化。方法选择2021年6月—2022年6月上海市普陀区中心医院消化内科门诊诊断为NAFLD的患者20例作为研究对象,采用有氧运动进行干预。收集患者基本信息、... 目的探讨有氧运动干预4周前后非酒精性脂肪肝病(NAFLD)患者临床特征及血清代谢产物变化。方法选择2021年6月—2022年6月上海市普陀区中心医院消化内科门诊诊断为NAFLD的患者20例作为研究对象,采用有氧运动进行干预。收集患者基本信息、肝生化、血脂指标,同时测定血清样本代谢产物的变化,分析干预前后差异性代谢产物。结果NAFLD患者体质量由干预前(72.21±7.44)kg下降至(70.63±7.25)kg;BMI由(25.39±1.32)kg/m^(2)下降至(24.83±1.39)kg/m^(2);腰围由原来的(96.52±6.61)cm降至(93.76±6.23)cm,差异均具有统计学意义(P<0.05);ALT、AST、AKP及GGT和CHE干预后分别为[21.00(17.00,25.00)、13.00(9.00,19.50)、68.32±24.14、18.00(14.50,35.50)、(6466.92±1402.02)U/L]较干预前显著下降,差异具有统计学意义(P<0.05)。TG及LDL干预后分别为[1.14(1.05,1.48)mmol/L、(2.48±0.57)mmol/L]较干预前显著下降,差异具有统计学意义(P<0.05)。血清代谢组学鉴定到31种潜在的差异代谢物,大部分为脂类及氨基酸类。结论有氧运动干预可以减轻NAFLD患者的体质量,改善血生化指标,同时改善NAFLD患者脂质及氨基酸代谢,从而有效减缓NAFLD的进展。这对于为NAFLD患者制定合理运动治疗方案有着重要临床意义。 展开更多
关键词 有氧运动 非酒精性脂肪肝 血清代谢组学
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不同年龄非酒精性脂肪性肝病合并急性药物性肝损伤患者的临床特点分析
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作者 张思敏 袁乙富 +3 位作者 吴小溪 杜晟楠 曹勤 蒋元烨 《肝脏》 2023年第9期1088-1092,共5页
目的探讨非酒精性脂肪肝(NAFLD)合并急性药物性肝损伤(DILI)患者的临床特点。方法选取上海中医药大学附属普陀医院2020年至2022年住院及门诊治疗的68例NAFLD合并急性DILI临床患者的一般资料、既往使用药物资料及实验室数据,进行统计分... 目的探讨非酒精性脂肪肝(NAFLD)合并急性药物性肝损伤(DILI)患者的临床特点。方法选取上海中医药大学附属普陀医院2020年至2022年住院及门诊治疗的68例NAFLD合并急性DILI临床患者的一般资料、既往使用药物资料及实验室数据,进行统计分析。结果导致急性DILI的前五位药物依次为心血管系统药、非甾体消炎药、抗痛风药、糖尿病药、抗肿瘤药。65例(95.59%)临床评估为1级(轻度)。青中年组ALT高于老年组,为88(60.5)U/L比58.5(24.25)U/L(P<0.01);青中年组HDL、Apo A指标低于老年组,为1.09(0.3525)μmol/L比1.21(0.3425)μmol/L、(1.15±0.27)g/L比(1.34±0.22)g/L(P<0.05),Apo B指标高于老年组,为0.88(0.28)g/L比0.74(0.27)g/L(P<0.05)。青中年组N低于老年组,为(52.17±9.3)%比(57.94±9.05)%(P<0.05),而L、PLT高于老年组为(36.11±8.93)%比(30.86±8.56)%、248.5(63.75)×10^(9)/L比205.5(69.25)×10^(9)/L(P<0.05)。结论NAFLD合并急性DILI患者临床以轻度肝损伤为主;与青中年人群相比,老年NAFLD患者发生急性DILI的概率更大,但总体损伤程度与年龄无直接相关性。诱发急性DILI的药物可能与老年基础疾病用药相关。 展开更多
关键词 非酒精性脂肪性肝病 急性药物性肝损伤 临床特点
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瘦型非酒精性脂肪性肝病的临床特征及血清脂质组学研究
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作者 张思敏 杜晟楠 +3 位作者 袁乙富 何诗嘉 曹勤 蒋元烨 《肝脏》 2023年第7期799-805,共7页
目的比较瘦型非酒精性脂肪性肝病(NAFLD)患者与瘦型健康人群的临床数据和血清脂质差异。方法收集瘦型NAFLD患者57例以及瘦型健康对照50例。记录所有受试者的临床信息以及血液生化指标数据,应用超高效液相色谱-高分辨静电场轨道阱质谱(UP... 目的比较瘦型非酒精性脂肪性肝病(NAFLD)患者与瘦型健康人群的临床数据和血清脂质差异。方法收集瘦型NAFLD患者57例以及瘦型健康对照50例。记录所有受试者的临床信息以及血液生化指标数据,应用超高效液相色谱-高分辨静电场轨道阱质谱(UPLC-Orbitrap MS)进行血清脂质组学分析;使用主成分分析法(PCA)和正交偏最小二乘法判别分析(OPLS-DA)对脂质组学数据进行多元统计分析。结果两组之间性别差异有统计学意义(P<0.05);瘦型NAFLD组BMI显著高于瘦型对照组(P<0.01)。瘦型NAFLD组WBC、RBC、HGB、HCT、肌酐、尿酸、γ-GT、ALT、TG分别为(6.10±1.57)×10^(9)/L、4.51(4.34,4.81)×10^(12)/L、137(127,148)g/L、41.1(38.15,43.7)%、67(57.5,81)μmol/L、339.5(298.75,380)μmol/L、27(19,37)U/L、14.5(9,21.25)U/L、1.42(0.95,1.95)μmol/L显著高于对照组(P<0.05),而瘦型NAFLD组的HDL、APOA1分别为1.27(1.10,1.52)μmol/L、1.39(1.26,1.57)g/L显著低于对照组(P<0.05)。脂质组学结果显示两组之间脂质代谢具有明显差异,共鉴定到差异性脂质(VIP值>1、P<0.05且两组间含量差异倍数FC>1.5)570种,主要为磷脂酰胆碱(PC)、三酰甘油(TG)、鞘磷脂(SM)、溶血磷脂酰胆碱(LPC)、磷脂酰乙醇胺(PE)、双甘脂(DG)、溶血磷脂酰乙醇胺(LPE)、神经酰胺(Cer)。与对照组相比,瘦型NAFLD组血清脂质大多数呈上调趋势;在呈下调趋势的脂质中,主要为SM(22种)和PC(22种)。结论与瘦型健康人群相比,瘦型NAFLD患者可能存在代谢异常、肝功能受损、胰岛素抵抗。 展开更多
关键词 非酒精性脂肪性肝病 瘦型 非肥胖 脂质组学
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多胺浸种对鸭茅抗旱性的影响 被引量:1
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作者 季杨 梁小玉 +1 位作者 易军 胡远彬 《草学》 2017年第3期36-40,共5页
以四川主推的3个鸭茅(Dactylis glomerata L.)饲用型品种宝兴、滇北和川东为研究对象,对其进行多胺浸种及干旱处理。通过测定其相对发芽率、相对发芽势、发芽率、相对根长、相对苗长、相对胚芽鞘长等指标,研究多胺浸种对鸭茅抗旱性的影... 以四川主推的3个鸭茅(Dactylis glomerata L.)饲用型品种宝兴、滇北和川东为研究对象,对其进行多胺浸种及干旱处理。通过测定其相对发芽率、相对发芽势、发芽率、相对根长、相对苗长、相对胚芽鞘长等指标,研究多胺浸种对鸭茅抗旱性的影响。结果表明:PEG胁迫降低了3个鸭茅品种的发芽能力、发芽速度及活力,抑制了胚根、胚芽及胚芽鞘的生长。综合各指标评定,3个鸭茅品种种子萌发期的抗旱性表现为宝兴>滇北>川东。精胺和腐胺浸种能不同程度提高3个品种抗旱性,且精胺浸种对宝兴和滇北品种的作用较腐胺更为显著。 展开更多
关键词 鸭茅 多胺 种子萌发 抗旱性
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水溶性环己酮-三聚氰胺-甲醛共缩聚树脂的合成与表征
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作者 吴灿 张一甫 +1 位作者 李勇强 陈文渊 《化学与粘合》 CAS 2018年第4期264-268,共5页
以环己酮、三聚氰胺、甲醛为原料,氢氧化钠为催化剂,用"两步法"合成出环己酮-三聚氰胺-甲醛树脂(CMFR),考察了三聚氰胺用量、醛酮物质的量比、催化剂用量及反应时间等对CMFR的游离甲醛含量及溶水倍数的影响,并借助FT-IR、13C-... 以环己酮、三聚氰胺、甲醛为原料,氢氧化钠为催化剂,用"两步法"合成出环己酮-三聚氰胺-甲醛树脂(CMFR),考察了三聚氰胺用量、醛酮物质的量比、催化剂用量及反应时间等对CMFR的游离甲醛含量及溶水倍数的影响,并借助FT-IR、13C-NMR、DSC、TG等对CMFR进行了表征。发现在环己酮、三聚氰胺、甲醛物质的量比为1.0∶0.2∶2.0,催化剂用量为0.6%,反应时间为120min,反应温度为90℃的条件下,合成出的CMFR游离甲醛含量为0.45%,溶水倍数为8.2。FT-IR和13C-NMR结果表明CMFR分子中存在三聚氰胺结构;DSC分析表明CMFR仅存在一个固化放热峰,说明三聚氰胺参与了树脂的共缩聚反应,形成了均一的分子结构,其固化温度约为182.5℃,固化后CMFR的耐溶剂性能提高。 展开更多
关键词 环己酮 三聚氰胺 甲醛 缩聚
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雌性普通?孵化投入研究
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作者 李松昊 张立世 +2 位作者 孙一夫 姜云垒 姚纪元 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2018年第1期105-108,共4页
2015—2016年3—7月在吉林省左家自然保护区,采用录像和直接观察法,对人工巢箱条件下雌性普通?孵化投入进行了研究,分析了窝卵数、首枚卵产期及雌鸟的身体条件对孵化期投入的影响.结果表明:雌性普通?坐巢时长与窝卵数呈显著正相关(r=0.7... 2015—2016年3—7月在吉林省左家自然保护区,采用录像和直接观察法,对人工巢箱条件下雌性普通?孵化投入进行了研究,分析了窝卵数、首枚卵产期及雌鸟的身体条件对孵化期投入的影响.结果表明:雌性普通?坐巢时长与窝卵数呈显著正相关(r=0.705,P<0.001);不同孵化阶段坐巢时长存在差异;雌鸟身体条件与孵化期坐巢时长呈显著正相关(r=0.444,P=0.050).说明雌性普通?可根据身体条件和窝卵数调整繁殖投入. 展开更多
关键词 普通 窝卵数 身体条件 繁殖投入
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