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miR-24-3p promotes proliferation and inhibits apoptosis of porcine granulosa cells by targeting P27
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作者 Shengjie Shi Lutong Zhang +7 位作者 Liguang Wang Huan Yuan Haowei Sun Mielie Madaniyati Chuanjiang Cai Weijun Pang lei gao Guiyan Chu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1315-1328,共14页
Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landra... Ovarian follicle development is associated with the physiological functions of granulosa cells(GCs),including proliferation and apoptosis.The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows.However,the functions of miR-24-3p on GCs are unclear.In this study,using flow cytometry,5-ethynyl-2′-de-oxyuridine(EdU)staining,and cell count,we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes,moreover,miR-24-3p inhibited GC apoptosis.Mechanistically,on-line prediction,bioinformatics analysis,a luciferase reporter assay,RT-qPCR,and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B(P27/CDKN1B).Furthermore,the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression.These findings suggest that miR-24-3p regulates the physiological functions of GCs. 展开更多
关键词 miR-24-3p granulosa cells PROLIFERATION APOPTOSIS
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Acoustic Bilayer Gradient Metasurfaces for Perfect and Asymmetric Beam Splitting
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作者 权家琪 孙宝印 +2 位作者 伏洋洋 高雷 徐亚东 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第1期39-50,共12页
We experimentally and theoretically present a paradigm for the accurate bilayer design of gradient metasurfaces for wave beam manipulation,producing an extremely asymmetric splitting effect by simply tailoring the int... We experimentally and theoretically present a paradigm for the accurate bilayer design of gradient metasurfaces for wave beam manipulation,producing an extremely asymmetric splitting effect by simply tailoring the interlayer size.This concept arises from anomalous diffraction in phase gradient metasurfaces and the precise combination of the phase gradient in bilayer metasurfaces.Ensured by different diffraction routes in momentum space for incident beams from opposite directions,extremely asymmetric acoustic beam splitting can be generated in a robust way,as demonstrated in experiments through a designed bilayer system.Our work provides a novel approach and feasible platform for designing tunable devices to control wave propagation. 展开更多
关键词 SURFACES SPLITTING ASYMMETRIC
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基于高端复合人才培养目标探索线性代数教学改革 被引量:1
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作者 李冬果 高磊 +1 位作者 郑文新 李林 《数理医药学杂志》 CAS 2023年第11期874-880,共7页
目的探索线性代数课程教学内容设置,改革教学方法,以适应临床医学高端复合型人才——首都医科大学阶平班的培养目标对数理基础课程的要求。方法基于“具有为新知识产生、新技能的发现做出贡献的意识”定位而培养学生抽象思维能力、逻辑... 目的探索线性代数课程教学内容设置,改革教学方法,以适应临床医学高端复合型人才——首都医科大学阶平班的培养目标对数理基础课程的要求。方法基于“具有为新知识产生、新技能的发现做出贡献的意识”定位而培养学生抽象思维能力、逻辑推理能力强的要求,在本科阶段第一学期设置48学时线性代数课程,开展以线性空间为主线设置教学内容的课程教学模式研究。结果将教学内容分为包含重难点的讲授内容、包含一般知识点和计算技能的学生自学内容及课下探索延伸性内容三个层面,将课堂教学与课后全时段全方位的讨论、答疑互动融合,形成了线性代数教学的新模式。结论基于高端复合人才培养目标的线性代数教学改革可为符合培养目标需求的人才培养体系的构建提供借鉴,为下一步教学模式的推广奠定基础。 展开更多
关键词 线性代数 教学改革 教学模式
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Oleic acid reduces steroidogenesis by changing the lipid type stored in lipid droplets of ovarian granulosa cells 被引量:1
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作者 Xiaoge Zhou Zhaoyi Mo +10 位作者 Yankun Li Liang Huang Sihai Yu Lan Ge Yamei Hu Shengjie Shi Lutong Zhang Liguang Wang lei gao Gongshe Yang Guiyan Chu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期756-768,共13页
Background:Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state,and it may have detrimental effects on female reproduction and fertility.Oleic acid induces lipid a... Background:Oleic acid is an abundant free fatty acid present in livestock that are in a negative energy-balance state,and it may have detrimental effects on female reproduction and fertility.Oleic acid induces lipid accumulation in bovine granulosa cells,which leads to a foam cell-like morphology and reduced steroidogenesis.However,why oleic acid increases lipid accumulation but decreases steroidogenesis remains unclear.This study focused on oleic acid’s effects on lipid type and steroidogenesis.Results:Oleic acid increased the lipid accumulation in a concentration-dependent manner and mainly increased the triglyceride level and decreased the cholesterol ester level.Oleic acid also led to a decline in estradiol and progesterone production in porcine granulosa cells in vitro.In addition,oleic acid up-regulated the expression of CD36 and diacylglycerol acyltransferase 2,but down-regulated the expression of 3-hydroxy-3-methylglutarylcoenzyme A reductase,scavenger receptor class B member 1 and acetyl-Coenzyme A acetyltransferase 2,as well as steroidogenesis-related genes,including cytochrome P450 family 11 subfamily A member 1,cytochrome P450family 19 subfamily A member 1 and 3 as well as steroidogenic acute regulatory protein at the mRNA and protein levels.An oleic acid-rich diet also enhanced the triglyceride levels and reduced the cholesterol levels in ovarian tissues of female mice,which resulted in lower estradiol levels than in control-fed mice.Compared with the control,decreases in estrus days and the numbers of antral follicles and corpora lutea,as well as an increase in the numbers of the atretic follicles,were found in the oleic acid-fed female mice.Conclusions:Oleic acid changed the lipid type stored in lipid droplets of ovarian granulosa cells,and led to a decrease in steroidogenesis.These results improve our understanding of fertility decline in livestock that are in a negative energy-balance state. 展开更多
关键词 FERTILITY Granulosa cell Lipid droplet Oleic acid Steroidogenesis
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产几丁质酶高原菌的分离鉴定及酶学性质初步研究
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作者 权淑静 杨文玲 +4 位作者 雷高 王佰涛 刁文涛 梁博 刘德海 《中国酿造》 CAS 北大核心 2023年第11期152-156,共5页
该研究通过透明圈法进行菌株初筛和几丁质酶活力测定进行复筛,从西藏日喀则地区土壤中分离筛选高产几丁质酶的菌株,通过形态观察、生理生化试验及16S rDNA序列分析对菌株进行鉴定,并对其产酶酶学性质进行初步研究,同时利用薄层层析(TLC... 该研究通过透明圈法进行菌株初筛和几丁质酶活力测定进行复筛,从西藏日喀则地区土壤中分离筛选高产几丁质酶的菌株,通过形态观察、生理生化试验及16S rDNA序列分析对菌株进行鉴定,并对其产酶酶学性质进行初步研究,同时利用薄层层析(TLC)分析其对几丁质的酶解产物。结果表明,从西藏日喀则地区土壤中分离筛选到一株高产几丁质酶的菌株RGZ2-4-5,经鉴定为Massilia aquatica,其几丁质酶活力为242.36 U/mL。该菌株所产胞外几丁质酶的最适反应温度为50℃,最适反应pH值为5.0,在温度30~40℃、pH 5.0~7.0条件下稳定性较好,金属离子Zn^(2+)、Mn^(2+)、Fe^(2+)、Cr^(2+)、Ag^(+)、Co^(2+)及苯甲基磺酰氟(PMSF)对酶活抑制作用显著(P<0.05),而其他金属离子对酶活无显著的促进或抑制作用(P>0.05)。该酶水解几丁质的最终产物为几丁二糖[(GlcNAc)2]和几丁单糖(GlcNAc)。 展开更多
关键词 几丁质酶 筛选 鉴定 酶学性质 薄层层析
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基于高通量测序分析不同地区魔芋根际土壤细菌群落多样性
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作者 雷高 李珊珊 +3 位作者 李亮亮 王佰涛 杨文玲 刘德海 《中国酿造》 CAS 北大核心 2023年第11期99-103,共5页
以昆明、宁德、南阳3地区魔芋种植区域土壤为研究对象,使用Illumina MiSeq高通量测序技术,对细菌16S rRNA的V3~V4可变区进行测序,探究魔芋不同地区魔芋根际土壤中细菌群落结构和多样性的差异。结果表明,3处魔芋根际土壤样品共得到38372... 以昆明、宁德、南阳3地区魔芋种植区域土壤为研究对象,使用Illumina MiSeq高通量测序技术,对细菌16S rRNA的V3~V4可变区进行测序,探究魔芋不同地区魔芋根际土壤中细菌群落结构和多样性的差异。结果表明,3处魔芋根际土壤样品共得到383726条有效序列,昆明、宁德、南阳样品分别得到2452种、2798种、2906种操作分类单元(OTUs)。Chao1指数、Ace指数、Shannon指数分析结果显示,3处土壤样品中细菌物种丰富度和多样性存在显著差异(P<0.05)。在属水平上,3地区魔芋根际土壤中细菌种类存在差异。昆明土壤样品中优势菌属(相对丰度≥1%)有12个,其中热酸菌属(Acidothermus)和芽单胞菌属(Gemmatimonas)为其独有;宁德土壤样品中优势菌属有7个,其中微杆菌属(Microbacterium)为其特有;南阳土壤样品中优势菌属有8个,芽孢杆菌属(Bacillus)为其独有。表明不同地区魔芋根际土壤细菌优势菌属存在明显不同。 展开更多
关键词 高通量测序技术 魔芋 根际土壤 细菌 群落结构
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1株高产乳酸粪肠球菌的筛选、鉴定及益生性能的研究
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作者 王佰涛 王秋菊 +3 位作者 雷高 杨文玲 权淑静 刘德海 《饲料研究》 CAS 北大核心 2023年第1期95-99,共5页
研究旨在获得能够高产乳酸的畜源益生菌。试验从新鲜仔猪粪便中筛选得到一批乳酸菌,根据碳酸钙透明圈结果和乳酸含量测定结果得到1株高产乳酸菌株SWS50,对其进行形态特征、生理生化特征、分子生物学结果及系统发育树等鉴定,并进行抑菌... 研究旨在获得能够高产乳酸的畜源益生菌。试验从新鲜仔猪粪便中筛选得到一批乳酸菌,根据碳酸钙透明圈结果和乳酸含量测定结果得到1株高产乳酸菌株SWS50,对其进行形态特征、生理生化特征、分子生物学结果及系统发育树等鉴定,并进行抑菌试验、抗逆性试验和胃肠道模拟试验。结果显示,菌株SWS50为粪肠球菌,培养48 h后乳酸产量最高可达117.9 mmol/L;菌株SWS50对金黄色葡萄球菌和沙门氏菌表现出较强的抑制作用;菌株SWS50具有较高的抗胆盐能力和耐酸能力,在人工肠液中基本可正常生长,存活率较高。研究表明,菌株SWS50具有较强的抗逆特性和一定的胃肠道存活能力,可发展为畜禽领域应用的潜力益生菌。 展开更多
关键词 乳酸菌 筛选 鉴定 粪肠球菌
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1株产蛋白酶罗伊氏乳杆菌的筛选及其制备发酵豆粕特性研究
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作者 王佰涛 雷高 +2 位作者 杨文玲 权淑静 林辉山 《饲料研究》 CAS 北大核心 2023年第15期84-87,共4页
试验旨在筛选1株产蛋白酶的罗伊氏乳杆菌,并研究其制备发酵豆粕的特性。试验从猪场新鲜仔猪粪便中获取了1株产蛋白酶乳酸菌WBT0063,根据该菌株的外观形态特征、生化分析、序列信息比对结果等综合鉴定该菌株为罗伊氏乳杆菌。利用罗伊氏... 试验旨在筛选1株产蛋白酶的罗伊氏乳杆菌,并研究其制备发酵豆粕的特性。试验从猪场新鲜仔猪粪便中获取了1株产蛋白酶乳酸菌WBT0063,根据该菌株的外观形态特征、生化分析、序列信息比对结果等综合鉴定该菌株为罗伊氏乳杆菌。利用罗伊氏乳杆菌发酵豆粕试验的结果显示,发酵后产物的抗营养因子水平明显下降,酸溶蛋白、小肽、粗蛋白、粗脂肪等营养成分含量明显提高。研究表明,该罗伊氏乳杆菌菌株发酵豆粕能够明显提高豆粕的营养成分,可以作为发酵豆粕的理想菌株。 展开更多
关键词 罗伊氏乳杆菌 发酵豆粕 蛋白酶 营养成分
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Donor-derived CD 19 CAR-T Cells versus Chemotherapy Plus Donor Lymphocyte Infusion for Treatment of Recurrent CD 19-positive B-ALL after Allogeneic Hematopoietic Stem Cell Transplantation 被引量:2
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作者 Xu TAN Xiao-qi WANG +11 位作者 Cheng ZHANG Xian-lan ZHAO Han YAO Guo CHEN Ying-ying MA Qin WEN lei gao Li gao Pei-yan KONG Yan SHEN Xi ZHANG Shi-feng LOU 《Current Medical Science》 SCIE CAS 2023年第4期733-740,共8页
Objective:This study aimed to compare the efficacy of anti-CD19 chimeric antigen receptor T cells(CAR-T cells)versus chemotherapy plus donor lymphocyte infusion(chemo-DLI)for treating relapsed CD 19-positive B-cell ac... Objective:This study aimed to compare the efficacy of anti-CD19 chimeric antigen receptor T cells(CAR-T cells)versus chemotherapy plus donor lymphocyte infusion(chemo-DLI)for treating relapsed CD 19-positive B-cell acute lymphoblastic leukemia(B-ALL)after allogeneic hematopoietic stem cell transplantation(allo-HSCT).Methods:Clinical data of 43 patients with B-ALL who relapsed after allo-HSCT were retrospectively analyzed.Twenty-two patients were treated with CAR-T cells(CAR-T group),and 21 with chemotherapy plus DLI(chemo-DLI group).The complete remission(CR)and minimal residual disease(MRD)-negative CR rates,leukemia-free survival(LFS)rate,overall survival(OS)rate,and incidence of acute graft-versus-host disease(aGVHD),cytokine release syndrome(CRS)and immune effector cell-associated neurotoxicity syndrome(ICANS)were compared between the two groups.Results:The CR and MRD-negative CR rates in the CAR-T group(77.3%and 61.5%)were significantly higher than those in the chemo-DLI group(38.1%and 23.8%)(P=0.008 and P=0.003).The 1-and 2-year LFS rates in the CAR-T group were superior to those in the chemo-DLI group:54.5%and 50.0%vs.9.5%and 4.8%(P=0.0001 and P=0.00004).The 1-and 2-year OS rates in the CAR-T versus chemo-DLI group were 59.1%and 54.5%vs.19%and 9.5%(P=0.011 and P=0.003).Six patients(28.6%)with grade 2-4 aGVHD were identified in the chemo-DLI group.Two patients(9.1%)in the CAR-T group developed grade 1-2 aGVHD.Nineteen patients(86.4%)developed CRS in the CAR-T group,comprising grade 1-2 CRS in 13 patients(59.1%)and grade 3 CRS in 6 patients(27.3%).Two patients(9.1%)developed grade 1-2 ICANS.Conclusion:Donor-derived anti-CD19 CAR-T-cell therapy may be better,safer,and more effective than chemo-DLI for B-ALL patients who relapse after allo-HSCT. 展开更多
关键词 CD19-positive B-cell acute lymphoblastic leukemia relapse donor-derived CD19 chimeric antigen receptor T cells chemo-donor lymphocyte infusion
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CLOCK inhibits the proliferation of porcine ovarian granulosa cells by targeting ASB9
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作者 Liang Huang Huan Yuan +7 位作者 Shengjie Shi Xiangrong Song Lutong Zhang Xiaoge Zhou lei gao Weijun Pang Gongshe Yang Guiyan Chu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期1969-1985,共17页
Background Clock circadian regulator(CLOCK)is a core factor of the mammalian biological clock system in regulat-ing female fertility and ovarian physiology.However,CLOCK’s specific function and molecular mechanism in... Background Clock circadian regulator(CLOCK)is a core factor of the mammalian biological clock system in regulat-ing female fertility and ovarian physiology.However,CLOCK’s specific function and molecular mechanism in porcine granulosa cells(GCs)remain unclear.In this study,we focused on CLOCK’s effects on GC proliferation.Results CLOCK significantly inhibited cell proliferation in porcine GCs.CLOCK decreased the expression of cell cycle-related genes,including CCNB1,CCNE1,and CDK4 at the mRNA and protein levels.CDKN1A levels were upregulated by CLOCK.ASB9 is a newly-identified target of CLOCK that inhibits GC proliferation;CLOCK binds to the E-box element in the ASB9 promoter.Conclusions These findings suggest that CLOCK inhibits the proliferation of porcine ovarian GCs by increasing ASB9 level. 展开更多
关键词 ASB9 CLOCK Granulosa cells PIG PROLIFERATION
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BnbHLH92a negatively regulates anthocyanin and proanthocyanidin biosynthesis in Brassica napus
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作者 Ran Hu Meichen Zhu +13 位作者 Si Chen Chengxiang Li Qianwei Zhang lei gao Xueqin Liu Shulin Shen Fuyou Fu Xinfu Xu Ying Liang Liezhao Liu Kun Lu Hao Yu Jiana Li Cunmin Qu 《The Crop Journal》 SCIE CSCD 2023年第2期374-385,共12页
Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription fact... Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription factors involved in the regulation of anthocyanin and PAs biosynthesis have been characterized in rapeseed.In this study,we identified a transcription factor gene BnbHLH92a(BnaA06T0441000ZS)in rapeseed.Overexpressing BnbHLH92a both in Arabidopsis and in rapeseed reduced levels of anthocyanin and PAs.Correspondingly,the expression profiles of anthocyanin and PA biosynthesis genes(TT3,BAN,TT8,TT18,and TTG1)were shown by quantitative real-time PCR to be inhibited in BnbHLH92a-overexpressing Arabidopsis seeds,indicating that BnbHLH92a represses the anthocyanin and PA biosynthesis pathway in Arabidopsis.BnbHLH92a physically interacts with the BnTTG1 protein and represses the biosynthesis of anthocyanins and PAs in rapeseed.BnbHLH92a also binds directly to the BnTT18 promoter and represses its expression.These results suggest that BnbHLH92a is a novel upstream regulator of flavonoid biosynthesis in B.napus. 展开更多
关键词 Brassica napus L BnbHLH92a ANTHOCYANIN PROANTHOCYANIDINS Flavonoid pathway
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Heart rate response and recovery during exercise predict future delirium risk——A prospective cohort study in middle-to older-aged adults
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作者 lei gao Aden Gaba +5 位作者 Peng Li Richa Saxena Frank A.J.LScheer Oluwaseun Akeju Martin K.Rutter Kun Hu 《Journal of Sport and Health Science》 SCIE CSCD 2023年第3期312-323,共12页
Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the brain.There is now an increasing focus on how ca... Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the brain.There is now an increasing focus on how cardiovascular health interacts with neurocognitive disorders given their overlapping risk factors and links to subsequent dementia and mortality.One common indicator for cardiovascular health is the heart rate response/recovery(HRR)to exercise,but how this relates to future delirium is unknown.Methods:Electrocardiogram data were examined in 38,740 middle-to older-aged UK Biobank participants(mean age=58.1 years,range:40-72 years;47.3%males)who completed a standardized submaximal exercise stress test(15-s baseline,6-min exercise,and 1-min recovery)and required hospitalization during follow-up.An HRR index was derived as the product of the heart rate(HR)responses during exercise(peak/resting HRs)and recovery(peak/recovery HRs)and categorized into low/average/high groups as the bottom quartile/middle 2 quartiles/top quartile,respectively.Associations between 3 HRR groups and new-onset delirium were investigated using Cox proportional hazards models and a2-year landmark analysis to minimize reverse causation.Sociodemographic factors,lifestyle factors/physical activity,cardiovascular risk,comorbidities,cognition,and maximal workload achieved were included as covariates.Results:During a median follow-up period of 11 years,348 participants(9/1000)newly developed delirium.Compared with the high HRR group(16/1000),the risk for delirium was almost doubled in those with low HRR(hazard ratio=1.90,95%)confidence interval(95%CI):1.30-2.79,p=0.001)and average HRR(hazard ratio=1.54,95%CI:1.07-2.22,p=0.020)).Low HRR was equivalent to being 6 years older,a current smoker,or>3 additional cardiovascular disease risks.Results were robust in sensitivity analysis,but the risk appeared larger in those with better cognition and when only postoperative delirium was considered(n=147;hazard ratio=2.66,95%CI:1.46-4.85,p=0.001).Conclusion:HRR during submaximal exercise is associated with future risk for delirium.Given that HRR is potentially modifiable,it may prove useful for neurological risk stratification alongside traditional cardiovascular risk factors. 展开更多
关键词 Brain health DELIRIUM Exercise stress test UK Biobank
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Effects of fluorination on crystal structure and electrochemical performance of antiperovskite solid electrolytes
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作者 lei gao Manrong Song +9 位作者 Ruo Zhao Songbai Han Jinlong Zhu Wei Xia Juncao Bian Liping Wang Song gao Yonggang Wang Ruqiang Zou Yusheng Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期521-528,I0013,共9页
The development of all-solid-state lithium batteries(ASSLBs)depends on exploiting solid-state electrolytes(SSEs)with high ionic conductivity and electrochemical stability.Fluorination is generally considered to be an ... The development of all-solid-state lithium batteries(ASSLBs)depends on exploiting solid-state electrolytes(SSEs)with high ionic conductivity and electrochemical stability.Fluorination is generally considered to be an effective strategy to improve the ionic conductivity and electrochemical stability of inorganic SSEs.Here,we report the partial fluorination of the chlo rine sites in an antiperovskite,by which the orthorhombic Li_(2)OHCl was transformed into cubic Li_(2)OHCl_(0.9)F_(0.1),resulting in a fourfold increase in ionic conductivity at 30℃.The ab initio molecular dynamics simulations suggest that both the crystal symmetry and the anions electronegativity influence the diffusion of Li+in the antiperovskite structure.Besides,from the perspective of experiments and calculations,it is confirmed that fluorination is a feasible method to improve the electrochemical stability of antiperovskite SSEs.The LiFePO_(4)|Li cell based on Li_(2)OHCl_(0.9)F_(0.1) is also assembled and exhibits stable cycle performance,which indicates that fluorination of antiperovskite SSEs is an effective way to produce high-performance SSEs for practical application of ASSLBs. 展开更多
关键词 ANTIPEROVSKITE Solid-state electrolyte FLUORINATION Ionic conductivity
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Ultra-high spectral purity laser derived from weak external distributed perturbation
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作者 Laiyang Dang Ligang Huang +7 位作者 leilei Shi Fuhui Li Guolu Yin lei gao Tianyi Lan Yujia Li Lidan Jiang Tao Zhu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第2期39-48,共10页
Ultra-high spectral purity lasers are of considerable research interests in numerous fields such as coherent optical communication,microwave photonics,distributed optical fiber sensing,gravitational wave detection,opt... Ultra-high spectral purity lasers are of considerable research interests in numerous fields such as coherent optical communication,microwave photonics,distributed optical fiber sensing,gravitational wave detection,optical clock,and so on.Herein,to deeply purify laser spectrum with compact size under normal condition,we propose a novel and practical idea to effectively suppress the spontaneous radiation of the laser cavity through weak external distributed perturbation.Subsequently,a laser configuration consisting of a main lasing cavity and an external distributed feedback cavity is proposed.The feedback signal with continuous spatio-temporal phase transition controlled by a distributed feedback structure is injected into the main cavity,which can deeply suppress the coupling rate from the spontaneous radiation to the stimulated emission and extremely purify the laser spectrum.Eventually,an ultra-narrow linewidth on-chip laser system with a side mode suppression ratio greater than 80 dB,an output linewidth of 10 Hz,and a relative intensity noise less than-150 dB/Hz is successfully obtained under normal conditions.The proposed concept in this work provides a new perspective for extreme regulation of laser parameters by using weak external distributed perturbation,which can be valid for various gain-type lasers with wide wavelength bands. 展开更多
关键词 high-coherence weak external distributed perturbation narrow linewidth LASER
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A Review of Experimental Research on the Mode I Fracture Behavior of Bamboo
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作者 Yue Chen Haitao Li +3 位作者 lei gao Wei Xu Rodolfo Lorenzo Milan Gaff 《Journal of Renewable Materials》 SCIE EI 2023年第6期2787-2808,共22页
Bamboo is an eco-friendly material with light weight,high strength,short growth cycle and high sustainability,which is widely used in building structures.Engineered bamboo has further promoted the development of moder... Bamboo is an eco-friendly material with light weight,high strength,short growth cycle and high sustainability,which is widely used in building structures.Engineered bamboo has further promoted the development of modern bamboo structures due to its unrestricted size and shape.However,as a fiber-reinforced material,fracture damage,especially Mode I fracture damage,becomes the most likely damage mode of its structure,so Mode I fracture characteristics are an important subject in the research of mechanical properties of bamboo.This paper summarizes the current status of experimental research on the Mode I fracture properties of bamboo based on the three-point bending(TPB)method,the single-edge notched beam(SENB)method,the compact tension(CT)method and the double cantilever beam(DCB)method,compares the fracture toughness of different species of bamboo,analyzes the toughening mechanisms and fracture damage modes,discusses the applicability of different theoretical calculation methods,and makes suggestions for future research priorities,aiming to provide a reference for future research and engineering applications in related fields. 展开更多
关键词 Mode I fracture properties test method toughening mechanism fracture damage modes
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Polarization Raman spectra of graphene nanoribbons
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作者 许望伟 孙诗杰 +6 位作者 杨慕紫 郝振亮 高蕾 卢建臣 朱嘉森 陈建 蔡金明 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期568-573,共6页
The on-surface synthesis method allows the fabrication of atomically precise narrow graphene nanoribbons(GNRs),which bears great potential in electronic applications.Here,we synthesize armchair graphene nanoribbons(AG... The on-surface synthesis method allows the fabrication of atomically precise narrow graphene nanoribbons(GNRs),which bears great potential in electronic applications.Here,we synthesize armchair graphene nanoribbons(AGNRs)and chevron-type graphene nanoribbons(CGNRs)array on a vicinal Au(111112)surface using 10,10′-dibromo-9,9′-bianthracene(DBBA)and 6,12-dibromochrysene(DBCh)as precursors,respectively.This process creates spatially wellaligned GNRs,as characterized by scanning tunneling microscopy.AGNRs show strong Raman linear polarizability for application in optical modulation devices.Different from the distinct polarization of AGNRs,only weak polarization exists in CGNRs polarized Raman spectrum,which suggests that the presence of the zigzag boundary in the nanoribbon attenuates the polarization rate as an important factor affecting the polarization.We analyze the Raman activation mode of CGNRs using the peak polarization to expand the application of the polarization Raman spectroscopy in nanoarray analysis. 展开更多
关键词 graphene nanoribbons polarization Raman spectroscopy scanning tunneling microscopy
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Near-Field Thermal Splitter Based on Magneto-Optical Nanoparticles
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作者 葛文宣 胡杨 +1 位作者 高雷 吴小虎 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第11期66-72,共7页
Based on the many-body radiative heat transfer theory,we investigate a thermal splitter based on three magneto-optical In Sb nanoparticles.The system comprises a source with adjustable parameters and two drains with f... Based on the many-body radiative heat transfer theory,we investigate a thermal splitter based on three magneto-optical In Sb nanoparticles.The system comprises a source with adjustable parameters and two drains with fixed parameters.By leveraging the temperature and magnetic field dependence of the permittivity of In Sb,the direction of heat flux in the system can be controlled by adjusting the magnetic field or temperature at the source.Under magnetic field control,the coupling between the separated modes,and the suppression of the zero-field mode induced by the magnetic field,are utilized to achieve a thermal splitting ratio within the modulation range of 0.15–0.58.Furthermore,temperature control results in a thermal splitting ratio ranging from 0.15 to 0.99,as a result of the suppression of the zero-field mode by the magnetic field and the blue shift effect of the zero-field mode frequency increasing with temperature.Notably,the gap distance between nanoparticles does not significantly affect the splitting ratio.These findings provide valuable theoretical guidance for utilizing magneto-optical nanoparticles as thermal splitters and lay the groundwork for implementing complex heat flux networks using In Sb for energy collection and heat transfer control. 展开更多
关键词 SPLITTING THERMAL system
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Near-Field Radiative Heat Transfer between Disordered Multilayer Systems
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作者 田鹏 葛文宣 +3 位作者 李松松 高雷 蒋建华 徐亚东 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第6期92-97,共6页
Near-field radiative heat transfer(NFRHT) research is an important research project after a major breakthrough in nanotechnology. Based on the multilayer structure, we find that due to the existence of inherent losses... Near-field radiative heat transfer(NFRHT) research is an important research project after a major breakthrough in nanotechnology. Based on the multilayer structure, we find that due to the existence of inherent losses,the decoupling of hyperbolic modes(HMs) after changing the filling ratio leads to suppression of heat flow near the surface mode resonance frequency. It complements the physical landscape of enhancement of near-field radiative heat transfer by HMs and more surface states supported by multiple surfaces. More importantly, considering the difficulty of accurate preparation at the nanoscale, we introduce the disorder factor to describe the magnitude of the random variation of the layer thickness of the multilayer structure and then explore the effect on heat transfer when the layer thickness is slightly different from the exact value expected. We find that the near-field radiative heat flux decreases gradually as the disorder increases because of interlayer energy localization. However, the reduction in heat transfer does not exceed an order of magnitude, although the disorder is already very large. At the same time, the regulation effect of the disorder on NFRHT is close to that of the same degree of filling ratio,which highlights the importance of disordered systems. This work qualitatively describes the effect of disorder on heat transfer and provides instructive data for the fabrication of NFRHT devices. 展开更多
关键词 RADIATIVE MULTILAYER instru
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Retrospective Study Efficacy of pantoprazole plus perforation repair for peptic ulcer and its effect on the stress response
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作者 Zi-Yan Leng Jia-Hao Wang +2 位作者 lei gao Ke Shi Hai-Bing Hua 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第12期2757-2764,共8页
BACKGROUND Peptic ulcer(PU)is an abnormal phenomenon in which there is rupture of the mucosa of the digestive tract,which not only affects patients'normal life but also causes an economic burden due to its high me... BACKGROUND Peptic ulcer(PU)is an abnormal phenomenon in which there is rupture of the mucosa of the digestive tract,which not only affects patients'normal life but also causes an economic burden due to its high medical costs.AIM To investigate the efficacy of pantoprazole(PPZ)plus perforation repair in patients with PU and its effect on the stress response.METHODS The study subjects were 108 PU patients admitted between July 2018 and July 2022,including 58 patients receiving PPZ plus perforation repair[research group(RG)]and 50 patients given simple perforation repair[control group(CG)].The efficacy,somatostatin(SS)concentration,stress reaction[malondialdehyde(MDA),lipid peroxide(LPO)],inflammatory indices[tumor necrosis factor(TNF)-α,C-reactive protein(CRP),interleukin(IL)-1β],recurrence,and complications(perforation,hemorrhage,and pyloric obstruction)were compared.RESULTS The overall response rate was higher in the RG than in the CG.Patients in the RG and IL-1β were significantly reduced to lower levels than those in the CG.Lower recurrence and complication rates were identified in the RG group.CONCLUSION Therefore,PPZ plus perforation repair is conducive to enhancing treatment outcomes in PU patients,reducing oxidative stress injury and excessive inflammatory reactions,and contributing to low recurrence and complication rates. 展开更多
关键词 PANTOPRAZOLE Perforation repair Peptic ulcer EFFICACY Etress response
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Effects of Continuous Cropping and Crop Rotation on Fungal Diversity in Greenhouse Soil
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作者 lei gao 《Asian Agricultural Research》 2023年第4期44-46,共3页
[Objectives]To explore the effects of continuous cropping and crop rotation on fungal diversity in greenhouse soil.[Methods]Using the greenhouse soil grown with Ganoderma leucocontextum in different continuous(rotatio... [Objectives]To explore the effects of continuous cropping and crop rotation on fungal diversity in greenhouse soil.[Methods]Using the greenhouse soil grown with Ganoderma leucocontextum in different continuous(rotation)cropping years as experimental materials,the change trend of soil fungal diversity in different continuous(rotation)cropping years was studied.Through high-throughput sequencing technology combined with related bioinformatics methods,the richness,diversity index and community structure of the fungal ITS1+ITS2 region in the soil were analyzed.[Results]Continuous cropping or crop rotation could increase the diversity of microbial communities.Ascomycota,Basidiomycota and Zygomycota were dominant fungi.The proportion of Basidiomycota gradually increased with the increase of continuous cropping years,and the abundance decreased after crop rotation.[Conclusions]This study is intended to provide a theoretical basis for the research on continuous cropping and crop rotation obstacles. 展开更多
关键词 Ganoderma leucocontextum FUNGI DIVERSITY
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