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基于深度强化学习的C+L波段弹性光网络频谱分配算法
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作者 晏丹 冯楠 +4 位作者 左晓博 沈凌飞 任丹萍 胡劲华 赵继军 《光通信技术》 北大核心 2024年第3期23-29,共7页
针对C+L波段弹性光网络中受激喇曼散射(SRS)效应导致物理层损伤加剧的问题,提出一种基于深度强化学习(DRL)自适应调制格式的频谱分配算法,在路由阶段,采用K最短路由算法为业务请求预计算K条最短备选路径;在波段、调制格式与频谱分配阶段... 针对C+L波段弹性光网络中受激喇曼散射(SRS)效应导致物理层损伤加剧的问题,提出一种基于深度强化学习(DRL)自适应调制格式的频谱分配算法,在路由阶段,采用K最短路由算法为业务请求预计算K条最短备选路径;在波段、调制格式与频谱分配阶段,采用DRL进行智能化决策,并结合了2种奖励函数,以降低网络阻塞率并提高频谱使用效率。仿真结果表明,该算法能够有效降低阻塞率并提高频谱利用率。 展开更多
关键词 c%PlUS%l波段弹性光网络 路由与频谱分配 受激喇曼散射效应 深度强化学习 奖励设计
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基于外部气相沉积的S+C+L波段低色散斜率大有效面积非零色散位移光纤的设计与制备
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作者 查健江 王元达 +3 位作者 何学荣 侯伟 王敬胜 文建湘 《光子学报》 EI CAS CSCD 北大核心 2024年第2期52-63,共12页
针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第... 针对现有光纤无法满足宽带光密集波分复用系统传输和S+C+L波段粗波分复用的要求,设计了一种具有中心凹陷的三角形芯+环形的折射率剖面,利用外部气相沉积工艺制备了一种非零色散位移光纤,并通过调整第一芯层的相对折射率和第二芯层与第一芯层的半径比,探究了其对光纤衰减、色散斜率和有效面积等参数的影响。研究发现,当第一芯层的相对折射率逐渐增大且第二芯层与第一芯层半径比逐渐减小时,零色散波长和有效面积逐渐减小。当第一芯层的相对折射率在0.52%~0.53%,芯层半径比在2.6~2.7时,光纤的有效面积接近70μm^(2),零色散波长在1420 nm附近,在1550 nm波段的色散系数大于8 ps·nm^(-1)·km^(-1),色散斜率为0.059 ps·nm^(-2)·km^(-1),可以较好地抑制传输过程中光非线性效应,满足长途干线网与城域网的使用要求。 展开更多
关键词 光纤通信 非零色散位移光纤 外部气相沉积工艺 S%PlUS%c%PlUS%l波段 低色散斜率 大有效面积 波分复用
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血清3-NT UCH-L1对帕金森病并发认知功能障碍的诊断效能分析
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作者 王倩 刘丹 +2 位作者 秦伟伟 张杰文 袁艺铭 《中国实用神经疾病杂志》 2024年第8期1028-1032,共5页
目的探讨血清3-硝基酪氨酸(3-NT)、泛素C末端水解酶L1(UCH-L1)水平与帕金森病患者并发认知功能障碍的关系及其诊断价值。方法纳入驻马店市中心医院2020-07—2023-07诊治的104例帕金森病患者作为研究对象,根据蒙特利尔认知功能评估量表(M... 目的探讨血清3-硝基酪氨酸(3-NT)、泛素C末端水解酶L1(UCH-L1)水平与帕金森病患者并发认知功能障碍的关系及其诊断价值。方法纳入驻马店市中心医院2020-07—2023-07诊治的104例帕金森病患者作为研究对象,根据蒙特利尔认知功能评估量表(MoCA)评分将患者分为认知功能正常组48例和认知功能障碍组56例。采用酶联免疫吸附法检测血清3-NT、UCH-L1水平,采用Pearson法分析帕金森病认知功能障碍患者血清3-NT、UCH-L1水平与MoCA评分的相关性,采用受试者工作特征(ROC)曲线分析血清3-NT、UCH-L1水平对帕金森病患者认知功能障碍的诊断价值,采用Logistic多因素回归分析帕金森病患者认知功能障碍的影响因素。结果认知功能障碍组血清3-NT[(7.26±2.04)μg/L比(4.58±1.40)μg/L]、UCH-L1[(0.94±0.21)μg/L比(0.62±0.16)μg/L]水平及H-Y分期中/晚期患者比例(78.57%比16.67%)高于认知功能正常组(P<0.05)。认知功能障碍组语言[(4.93±0.52)分比(5.23±0.49)分]、命名[(2.11±0.35)分比(2.46±0.34)分]、注意力[(4.80±0.67)分比(5.31±0.45)分]、抽象思维[(1.21±0.26)分比(1.63±0.20)分]、视空间及执行能力[(2.89±0.39)分比(3.54±0.30)分]、定向力[(5.11±0.48)分比(5.50±0.31)分]、延迟记忆[(2.88±0.36)分比(4.02±0.41)分]、MoCA总分[(23.93±2.05)分比(27.69±1.08)分]低于认知功能正常组(P<0.05)。帕金森病认知功能障碍患者血清3-NT、UCH-L1水平与语言、命名、注意力、抽象思维、视空间及执行能力、定向力、延迟记忆、MoCA总分均呈负相关(P<0.05)。3-NT、UCH-L1单独及其联合诊断帕金森病患者认知功能障碍的AUC分别为0.869、0.852、0.951。3-NT、UCH-L1、H-Y分期均是帕金森病患者并发认知功能障碍的独立危险因素(P<0.05)。结论血清3-NT、UCH-L1水平可用于评估帕金森病患者认知功能障碍的发生。 展开更多
关键词 帕金森病 认知功能障碍 3-硝基酪氨酸 泛素c末端水解酶l1 血清 危险因素
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A Study of the Comets with Large Perihelion Distances C/2019 L3(ATLAS)and C/2019 O3(Palomar)
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作者 Alberto S.Betzler 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期199-213,共15页
This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS... This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at perihelion.The absolute magnitude of comets ATLAS and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 respectively.The cometary activity of comets ATLAS and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of 2026.The nucleus of comet ATLAS has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little larger.The c-o colors of the comets ATLAS and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP 1194.These comets showed a bluish trend in the coma color with decreasing heliocentric distance.Comet Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of dust.The slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign. 展开更多
关键词 individual c/2019 l3(ATlAS) c/2019 O3(Palomar) techniques:photometric methods:data analysis
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Optimizing Average Electric Power During the Charging of Lithium-Ion Batteries Through the Taguchi Method
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作者 Mohd H.S.Alrashdan 《Transactions of Tianjin University》 EI CAS 2024年第2期152-166,共15页
In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries fa... In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach. 展开更多
关键词 lithium-ion batteries Average electric power during charging Taguchi method cOMSOl Multiphysics software c rate l27 orthogonal array
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Bioactive chemical constituents from the marine-derived fungus Cladosporium sp.DLT-5
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作者 Luting DAI Qingyi XIE +6 位作者 Jiaocen GUO Qingyun MA Li YANG Jingzhe YUAN Haofu DAI Zhifang YU Youxing ZHAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期905-914,共10页
A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidat... A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidation determined the planar structure of 1.Subsequent electronic circular dichroism(ECD)experiment assigned the absolute configuration of 1.Compounds 1,2,4–6,and 10 displayed different degrees of neuroprotective activities on human neuroblastoma cells SH-SY5Y.Five compounds(1,3–5,and 13)emerged resistance to protein tyrosine phosphatase 1B(PTP1B),further kinetic analysis and molecular docking study indicated that the most potent compound 13(IC50value of 10.74±0.61μmol/L)was found as a noncompetitive inhibitor for PTP1B.Surface plasmon resonance(SPR)and molecular docking studies also demonstrated the interaction between compound 12 and Niemann-Pick C1 Like 1(NPC1L1),which has been identified as significant therapeutic target for hypercholesteremia.In addition,compounds 3,6,and 14 showed attractive inhibitory activity against the phytopathogenic fungi:Colletotrichum capsici.Therefore,library of Cladosporium metabolites is enriched and new active uses of known compounds are explored. 展开更多
关键词 cladosporium sp. marine-derived fungus neuroprotective effects protein tyrosine phosphatase 1B(PTP1B) Niemann-Pick c1 like 1(NPc1l1) antifungal activity
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Prognostic significance and relationship of SMAD3 phosphoisoforms and VEGFR-1 in gastric cancer:A clinicopathological study
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作者 Shi-Lin Lv Pei Guo +3 位作者 Jun-Rong Zou Ren-Sheng Chen Ling-Yu Luo De-Qiang Huang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期118-132,共15页
BACKGROUND The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer metastasis.SMAD3 phosphorylation is a crucial prognostic marker in gastric cancer.AIM To determine the prognostic value... BACKGROUND The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer metastasis.SMAD3 phosphorylation is a crucial prognostic marker in gastric cancer.AIM To determine the prognostic value and relationship of SMAD3 phospho-isoforms and VEGFR-1 in gastric cancer.METHODS This was a single-center observational study which enrolled 98 gastric cancer patients and 82 adjacent normal gastric tissues from patients aged 32-84 years(median age 65)between July 2006 and April 2007.Patients were followed up until death or the study ended(median follow-up duration of 28.5 mo).The samples were used to generate tissue microarrays(TMAs)for immunohistochemical(IHC)staining.The expressions of TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 in gastric cancer(GC)tumor tissue and normal tissue were measured by IHC staining using TMAs obtained from 98 GC patients.Prognosis and survival information of the patients was recorded by Outdo Biotech from May 2007 to July 2015.The relationship between TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 protein expression levels was analyzed using Pearson's correlation coefficient.The relationship between protein expression levels and clinicopathological parameters was analyzed using the Chi-squared test.A survival curve was generated using the Kaplan-Meier survival analysis.RESULTS TGFβ-1 and VEGFR-1 expression was significantly upregulated in gastric cancer tissue compared to adjacent noncancerous tissue.The positive expression of phosphorylated isoforms of Smad3 varied depending on the phosphorylation site[pSMAD3C(S423/425):51.0%and pSMAD3L(S204):31.6%].High expression of pSMAD-3L(S204)was significantly correlated with larger tumors(P=0.038)and later N stages(P=0.035).Additionally,high expression of VEGFR-1 was closely correlated with tumor size(P=0.015)and pathological grading(P=0.013).High expression of both pSMAD3L(S204)and VEGFR-1 was associated with unfavorable outcomes in terms of overall survival(OS).Multivariate analysis indicated that high expression of pSMAD3L(S204)and VEGFR-1 were independent risk factors for prognosis in GC patients.VEGFR-1 protein expression was correlated with TGF-β1(r=0.220,P=0.029),pSMAD3C(S423/425)(r=0.302,P=0.002),and pSMAD3L(S204)(r=0.201,P=0.047),respectively.Simultaneous overexpression of pSMAD3L(S204)and VEGFR-1 was associated with poor OS in gastric cancer patients.CONCLUSION Co-upregulation of pSMAD3L(S204)and VEGFR-1 can serve as a predictive marker for poor gastric cancer prognosis,and pSMAD3L(204)may be involved in enhanced gastric cancer metastasis in a VEGFR-1-dependent manner. 展开更多
关键词 Gastric cancer pSMAD3l(S204) pSMAD3c(S423/425) SURVIVAl Transforming growth factor-β1 VEGFR-1
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血清hs-CRP、sCD40L、β_(2)GP1、ACA与急性脑梗死病情严重程度及预后的相关性
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作者 冉学兵 《贵州医药》 CAS 2024年第9期1359-1365,共7页
目的分析血清hs-CRP、sCD40L、β_(2)GP1、ACA与ACI患者病情严重程度及预后的相关性。方法采取回顾性研究,选择2021年6月至2023年6月医院收治的130例ACI患者临床资料作为研究对象。患者均接受阿替普酶静脉溶栓治疗,根据美国国立卫生研... 目的分析血清hs-CRP、sCD40L、β_(2)GP1、ACA与ACI患者病情严重程度及预后的相关性。方法采取回顾性研究,选择2021年6月至2023年6月医院收治的130例ACI患者临床资料作为研究对象。患者均接受阿替普酶静脉溶栓治疗,根据美国国立卫生研究院卒中量表评分(NIHSS)评估患者病情严重程度,将评分<16分患者临床资料纳入轻中组,将评分≥16分患者临床资料纳入重度组;治疗2周后,参照改良Rankin量表评分(mRS)评估患者预后,将评分<3分患者临床资料纳入预后良好组,将评分≥3分患者临床资料纳入预后不良组;统计患者基线资料,采用双变量相关性Pearson(N)分析,ACI患者血清hs-CRP、sCD40L、β_(2)GP1、ACA水平与认知功能的相关;采用二元Logistic回归分析血清hs-CRP、sCD40L、β_(2)GP1、ACA与急性脑梗死病情严重程度及预后的相关性;采用接受者操作特性曲线(ROC)分析血清hs-CRP、sCD40L、β_(2)GP1、ACA水平对ACI患者预后不良的预测价值。结果治疗后,ACI患者Fib、D-D低于治疗前(P<0.05);治疗后,ACI患者hs-CRP、sCD40L、β_(2)GP1、ACA低于治疗前(P<0.05);ACI患者治疗前的MoCA评分分低于治疗后(P<0.001);Pearson(N)分析结果显示,ACI患者血清hs-CRP、sCD40L、β_(2)GP1、ACA水平与MoCA评分呈负相关(r<0,P<0.05);重度组TOAST分型为心源性栓塞患者占比高于轻中度组,Fib、D-D、hs-CRP、sCD40L、β_(2)GP1、ACA水平高于轻中度组(P<0.05);二元Logistic回归分析结果显示,TOAST分型为心源性栓塞、其他原因/不明原因,血清Fib、D-D、hs-CRP、sCD40L、β_(2)GP1、ACA高表达是ACI患者病情为重度的危险因素(OR>1,P<0.05);预后不良组TOAST分型为心源性栓塞患者占比高于预后良好组,发病至溶栓时间长于预后良好组,Fib、D-D、hs-CRP、sCD40L、β_(2)GP1、ACA水平高于预后良好组(P<0.05);二元Logistic回归分析结果显示,TOAST分型为心源性栓塞,发病至溶栓时间长、血清Fib、D-D、hs-CRP、sCD40L、β_(2)GP1、ACA高表达是ACI患者预后不良的危险因素(OR>1,P<0.05);绘制ROC曲线结果显示,血清hs-CRP、sCD40L、β_(2)GP1、ACA水平及联合检测ACI患者预后不良的ACU均>0.70,有一定预测价值,其中联合检测最高。结论TOAST分型、血清Fib、D-D、hs-CRP、sCD40L、β_(2)GP1、ACA水平与ACI患者病情严重程度相关,同时在此基础上发病至溶栓时间与ACI患者预后关系密切。 展开更多
关键词 急性脑梗死 超敏c反应蛋白 可溶性cD40l β_(2)-糖蛋白1 抗心磷脂抗体 病情 预后
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Essen卒中风险评分联合OX-LDL、UCH-1对非房颤人群首发急性缺血性脑卒中患者短期预后的预测价值
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作者 陈小沛 刘慧 《新疆医科大学学报》 CAS 2024年第2期254-258,263,共6页
目的探讨Essen卒中风险评分联合氧化型低密度脂蛋白胆固醇(Oxidized low-density lipoprotein,OX-LDL)、血清泛素C末端水解酶L1(Ubiquitin carboxy-terminal hydrolase-L1,UCH-L1)对非房颤人群首发急性缺血性脑卒中(Acute ischemic stro... 目的探讨Essen卒中风险评分联合氧化型低密度脂蛋白胆固醇(Oxidized low-density lipoprotein,OX-LDL)、血清泛素C末端水解酶L1(Ubiquitin carboxy-terminal hydrolase-L1,UCH-L1)对非房颤人群首发急性缺血性脑卒中(Acute ischemic stroke,AIS)患者短期预后的预测价值。方法根据改良Rankin量表(Modified rankin scale,mRS)评分,将132例非房颤人群首发AIS患者分为预后良好组(mRS≤2分)93例,预后不良组(mRS>2分)39例,在入院治疗前进行Essen卒中风险评分和血清OX-LDL、UCH-L1检测。采用Spearman相关性分析Essen卒中风险评分与OX-LDL、UCH-L1水平的差异,采用Logistic回归分析预后不良的危险因素,采用受试者工作特征(Receiver operating characteristic,ROC)曲线分析Essen卒中风险评分、OX-LDL、UCH-L1水平及三者联合对非房颤人群首发AIS预后评估的效果。结果预后不良组Essen卒中风险评分高于预后良好组(Z=-5.365,P<0.001),血清中OX-LDL、UCH-L1水平高于预后良好组(Z=-6.152,P<0.001;Z=-7.020,P<0.001)。血清中OX-LDL、UCH-L1水平与Essen评分呈正相关(r=0.629,P<0.001;r=0.598,P<0.001)。Logistic回归分析显示,Essen卒中风险评分、OX-LDL、UCH-L1是脑卒中预后的独立影响因素。Essen卒中风险评分联合OX-LDL、UCH-L1对非房颤人群首发AIS预后的ROC曲线下面积为0.896,灵敏度为88.54%,特异度为92.93%。结论Essen卒中风险评分联合OX-LDL、UCH-L1对非房颤人群首发AIS预后有良好的预测作用,Essen卒中风险评分、OX-LDL、UCH-L1水平越高,提示预后不良的风险越大。 展开更多
关键词 Essen卒中风险评分量表 氧化型低密度脂蛋白胆固醇 血清泛素c末端水解酶l1 急性缺血性脑卒中
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冠心病患者PCI术前后cTn-T、sCD40L、hs-CR与预后的相关性
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作者 张静静 刘彦铭 《云南医药》 CAS 2024年第5期48-51,共4页
目的分析冠心病患者PCI前后cTn-T、sCD40L、hs-CRP水平与预后的相关性。方法将本院行PCI术的192例患者根据术后12个月是否发生并发症及不良心脏事件分为预后良好组(n=156)和预后不良组(n=36),比较2组cTn-T、sCD40L、hs-CRP水平。建立RO... 目的分析冠心病患者PCI前后cTn-T、sCD40L、hs-CRP水平与预后的相关性。方法将本院行PCI术的192例患者根据术后12个月是否发生并发症及不良心脏事件分为预后良好组(n=156)和预后不良组(n=36),比较2组cTn-T、sCD40L、hs-CRP水平。建立ROC曲线分析血清cTn-T、sCD40L、hs-CRP水平对CAD的预测价值。结果2组术后24 h cTn-T、sCD40L、hs-CRP水平均高于术前、术后10 min,差异有统计学意义(P<0.05)。术后24 h预后不良组cTn-T、sCD40L、hs-CRP水平均高于预后良好组,差异有统计学意义(P<0.05)。cTn-T、sCD40L、hs-CRP预测PCI术后并发症及MACE的最佳截断值为0.36 mg/L、4.11mg/mL、8.28mg/mL,敏感度分别为55.26%、73.29%、81.28%,特异度分别为76.29%、51.42%、69.37%。三个指标联合检测的敏感度和特异度分别为84.29%、78.33%,高于单一指标。结论PCI可在一定程度上激活CAD患者血管局部及全身的炎症反应,导致心肌损伤,引发并发症及MACE。cTn-T、sCD40L、hs-CRP可作为评价CAD患者PCI预后的辅助指标。 展开更多
关键词 冠心病 经皮冠状动脉介入术 肌钙蛋白-T 可溶性cD40l 超敏c反应蛋白
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GPS现代化L1C民用信号体制分析
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作者 王轲 张健铤 +2 位作者 商晓燕 吴振伟 王志涛 《通信与信息技术》 2024年第4期97-101,共5页
为了保持国际竞争力的同时满足全球范围内不断增长的PNT服务需求,美国不断进行现代化全球定位系统(GPS)的升级改造,2020年启用并播发新的民用信号L1C就是重点改造内容之一。针对新形势下日趋激烈的频谱资源竞争环境,在对GPS四个民用信... 为了保持国际竞争力的同时满足全球范围内不断增长的PNT服务需求,美国不断进行现代化全球定位系统(GPS)的升级改造,2020年启用并播发新的民用信号L1C就是重点改造内容之一。针对新形势下日趋激烈的频谱资源竞争环境,在对GPS四个民用信号基本特征梳理归纳的基础上,阐述了L1C频点信号的选择背景及意义,分析了该信号的基本结构,重点研究了L1C信号的具体调制方式及重要特征,最后对伪码进行了详细分析,通过研究深入剖析L1C信号体制,对其他GNSS未来新体制信号的设计及工程实现有借鉴和参考价值。 展开更多
关键词 卫星导航 GPS现代化 l1c民用信号 信号体制
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Screening and Analysis of Germplasm Resources of Wild Coix lacryma-jobi L. with High Content of Coixin
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作者 Yubin ZHANG Xiaohong HE +3 位作者 Fanzhi LIU Qiuyi MENG Rong LIU Gang SHEN 《Medicinal Plant》 CAS 2019年第2期66-68,共3页
[Objectives] To screen and analyze germplasm resources of wild Coix lacryma-jobi L. with high content of coixin. [Methods] From the 150 kinds of collected wild C. lacryma-jobi L. germplasm resources, 24 kinds of excel... [Objectives] To screen and analyze germplasm resources of wild Coix lacryma-jobi L. with high content of coixin. [Methods] From the 150 kinds of collected wild C. lacryma-jobi L. germplasm resources, 24 kinds of excellent resources were screened and detected. Morphological statistics were carried out, and the content of coixin in the four organ of roots, stems, leaves and seeds were measured, and the approved cultivar white husk Liugu of C. lacryma-jobi L. was taking as the control. [Results] Among the organs of the plant of C. lacryma-jobi L., the roots had the highest content of coixin, so the roots of C. lacryma-jobi L. can be used as the medicinal parts of C. lacryma-jobi L. [Conclusions] The wild C. lacryma-jobi L.Y229, Y164, Y166, Y83, and Y84 stains had excellent yield, and their root coixin content was significantly higher than that of the control variety, so they can be used for cultivation as excellent germplasm, so as to obtain new variety(line) of C. lacryma-jobi L.with higher content of coixin. 展开更多
关键词 cOIX lacryma-jobi l. coixin GERMPlASM resources ORGANS MEDIcINAl use
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Extraction of Flavonoids from Leaves of Coix lacryma-jobi L.
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作者 Xiaoxiong FENG Yurun LIANG +4 位作者 Aiyue LUO Jiandan NONG Shaomei MO Yan NING Suoyi HUANG 《Medicinal Plant》 CAS 2018年第1期9-12,共4页
[Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried... [Objectives] To extract the flavonoids from leaves of Coix lacryma-jobi L. [Methods] Ethanol extraction method was adopted,spectrophotometry was used,and single factor experiment and orthogonal experiment were carried out to study the effects of ethanol percentage,extraction temperature,solid-to-liquid ratio and extraction time on the extraction of total flavonoids from leaves of C. lacryma-jobi L.[Results] The order of 4 factors influencing the extraction of flavonoids from leaves of C. lacryma-jobi L. was: solid-to-liquid ratio > extraction time > ethanol percentage > extraction temperature. When the extraction temperature was 70℃,the extraction time was 1. 5 h and the solid-liquid ratio was 1: 10,the ethanol percentage was 60%,the extraction effect was the best,extraction of flavonoids was 0. 107 5 mg/m L.[Conclusions] This study is expected to provide a theoretical basis for further development and utilization of C. lacryma-jobi L. 展开更多
关键词 leaves of coix lacryma-jobi l. FlAVONOIDS EXTRAcTION Single factor experiment Orthogonal experiment
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Effects of Thallium Stress on Photosynthesis, Chlorophyll Fluorescence Parameters and Antioxidant Enzymes Activities of Coix Lacryma-jobi
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作者 Gaozhong Pu Denan Zhang +2 位作者 Danjuan Zeng Guangping Xu Yuqing Huang 《Journal of Environmental Science and Engineering(A)》 2017年第1期15-21,共7页
Levels of T1 (Thallium) in soil from 0 (control) to 50 μg/L through 0.2, 0.5, 1 and 2.5μg/L were directly and positively correlated to levels of T1 in plant tissue, the accumulation being maximum in roots, inter... Levels of T1 (Thallium) in soil from 0 (control) to 50 μg/L through 0.2, 0.5, 1 and 2.5μg/L were directly and positively correlated to levels of T1 in plant tissue, the accumulation being maximum in roots, intermediate in leaves and minimum in stems. Thallium, especially at higher concentrations, adversely affected photosynthesis (as judged based on chlorophyll fluorescence parameters), suggesting inhibition of photo-activation of PSII (Photosystems II), and also decreased the rate of photosynthesis, the rate of transpiration and stomatal conductivity drastically. Exposure to TI also increased the activity of CAT (Catalase) (except at 1 μg/L) and POD (Peroxidase) (except at 0.2 μg/L), suggesting that the antioxidant systems in Coix lacryma-jobi were the main contributors of CAT and SOD (Superoxide Dismutase) and that the tolerance of C. lacryma-jobi to T1 is mainly due to this induced antioxidant machinery. 展开更多
关键词 Antioxidant enzyme coix lacryma-jobi l. chlorophyll fluorescence THAllIUM wetland.
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Effects of Different Herbicides on Weed Control,Agronomic Characters and Grain Quality of Coix lacryma-jobi L.
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作者 Maohong AO Zhiqin SONG Xiaoyu YANG 《Plant Diseases and Pests》 CAS 2022年第5期21-24,共4页
[Objectives]The paper was to study the effects of different herbicides on weed control,agronomic characters and grain quality of Coix lacryma-jobi L.[Methods]Six commonly used herbicides were selected for the trial,in... [Objectives]The paper was to study the effects of different herbicides on weed control,agronomic characters and grain quality of Coix lacryma-jobi L.[Methods]Six commonly used herbicides were selected for the trial,including atrazine SC,butachlor SC,monosulfuron WP,MCPA-starane EC,clopyralid AS and tribenuron-methyl WP.[Results](i)Atrazine,butachlor and monosulfuron had no chemical injury to C.lacryma-jobi L.,while clopyralid caused slight chemical injury.(ii)The fresh weight control effects of atrazine,butachlor and monosulfuron on weeds increased first and then decreased.The initial control effect of MCPA-starane and clopyralid reached more than 90%;the control effect of monosulfuron increased gradually in the late stage,reaching 97%at 60 d post spraying,and the overall control effect was optimal.(iii)Compared with manual weeding,herbicides had no significant effect on plant height of C.lacryma-jobi L.However,compared with no weeding,other herbicides except tribenuron-methyl inhibited plant growth to a certain extent.Herbicides had different effects on main stem diameter,tiller number per plant and grain number per plant of C.lacryma-jobi L.(iv)Different herbicides had no significant effect on 100-grain weight,but had significant effect on yield.(v)Compared with manual weeding,atrazine,butachlor and clopyralid decreased the protein content of C.lacryma-jobi L.,and the use of atrazine,butachlor,monosulfuron,MCPA-starane and tribenuron-methyl decreased the fat content of C.lacryma-jobi L.;butachlor and MCPA-starane decreased the glycerol trioleate content of C.lacryma-jobi L.Compared with no weeding,chemical herbicides had no significant effect on the protein content,while atrazine decreased the fat content,and butachlor and MCPA-starane decreased the glycerol trioleate content of C.lacryma-jobi L.[Conclusions]The use of herbicides significantly increases crop yield compared with no weeding,but has an impact on agronomic characters and grain quality. 展开更多
关键词 HERBIcIDE coix lacryma-jobi l. Weed control Agronomic character Grain quality
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新组合菌系SCB329-SCB933利用L-山梨糖发酵产生维生素C前体——2-酮基-L-古龙酸的研究 Ⅰ.新组合菌系SCB329-SCB933的生物学特性 被引量:37
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作者 尹光琳 何建明 +5 位作者 任双喜 宋祺 叶晴 林红雨 陈策实 郭新友 《工业微生物》 CAS CSCD 1997年第1期1-7,共7页
采用紫外照射、化学诱变和原生质融合等方法选育到一株性状更优良的突变株SCB329,并与新筛选的一株芽孢杆菌SCB933搭配组成新的组合菌系。产酸小菌SCB329与其亲本菌株氧化葡萄糖酸杆菌性状相似。伴生大菌SCB933属苏芸金芽孢杆菌(B.thur... 采用紫外照射、化学诱变和原生质融合等方法选育到一株性状更优良的突变株SCB329,并与新筛选的一株芽孢杆菌SCB933搭配组成新的组合菌系。产酸小菌SCB329与其亲本菌株氧化葡萄糖酸杆菌性状相似。伴生大菌SCB933属苏芸金芽孢杆菌(B.thuringiensis)。新组合菌系利用L-山梨糖的发酵液提取后经纸层析,元素分析和红外吸收光谱等项鉴定,其发酵产物确系2-酮基-L-古龙酸,对新组合菌系的生物学特性也进行了研究。 展开更多
关键词 l-山梨糖 维生素c 细菌 发酵 2酮基l古龙酸
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高平坦度的三级双泵浦结构C+L波段超荧光光源 被引量:13
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作者 贾振安 李丽 +1 位作者 乔学光 刘颖刚 《光学精密工程》 EI CAS CSCD 北大核心 2010年第3期558-562,共5页
为了使掺铒光纤超荧光光源C波段与L波段光谱匹配良好,实现高平坦度的C+L波段宽带光源,提出了一种三级双泵浦光源结构。首先,使用三段不同型号、不同长度的掺铒光纤,两个980nm激光二极管,波分复用器,隔离器以及3dB耦合器构成的光纤环形... 为了使掺铒光纤超荧光光源C波段与L波段光谱匹配良好,实现高平坦度的C+L波段宽带光源,提出了一种三级双泵浦光源结构。首先,使用三段不同型号、不同长度的掺铒光纤,两个980nm激光二极管,波分复用器,隔离器以及3dB耦合器构成的光纤环形镜搭建宽带光源实验装置;然后,通过不断优化三段掺铒光纤的长度,调节两级抽运源功率获得高平坦度C+L波段光源输出;最后对其产生机理进行分析。实验结果表明,当三段掺铒光纤的长度分别为11.5m、53m和6.5m,两级抽运源功率分别为65mW和115mW时,输出光谱的3dB带宽为75.68nm,在1543~1603nm波段光谱的平坦度<±1.3dB(不加任何滤波器的条件下)。获得的高平坦度C+L波段宽带光源可以更好地满足光纤传感、光纤通信系统等领域的应用要求。 展开更多
关键词 超荧光光纤光源 掺铒光纤 三级双泵浦结构 c%PlUS%l波段 高平坦度
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一种简单而性能优良的C+L波段掺铒宽带光源 被引量:8
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作者 乔学光 习聪玲 +1 位作者 贾振安 刘颖刚 《半导体光电》 EI CAS CSCD 北大核心 2007年第1期23-26,共4页
报道了一种结构简单、工作在C+L波段的掺铒宽带光源。实验中用3 dB宽带耦合器作为光纤反射镜,同时利用功率控制电路使光源输出光稳定,先用两个980 nm二极管作为抽运源,将后向的C波段ASE重新引回光纤中,提高了抽运源的利用效率和光纤输... 报道了一种结构简单、工作在C+L波段的掺铒宽带光源。实验中用3 dB宽带耦合器作为光纤反射镜,同时利用功率控制电路使光源输出光稳定,先用两个980 nm二极管作为抽运源,将后向的C波段ASE重新引回光纤中,提高了抽运源的利用效率和光纤输出光的稳定性,优化掺铒光纤长度,获得了功率高达26.67 mW(14.26 dBm)的C+L波段ASE光输出,平均波长1550.887 nm。之后采用一个二极管实现双抽运得到了同样的结果。 展开更多
关键词 波导与光纤光学 c%PlUS%l波段 掺铒光纤 超宽带光源 光纤环形镜 放大自发辐射
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c-FLIP(L)在乳腺癌中表达的意义及对凋亡的调节 被引量:3
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作者 臧凤琳 魏熙胤 +2 位作者 孙蕾娜 赵秀兰 孙保存 《中国肿瘤临床》 CAS CSCD 北大核心 2010年第15期841-845,共5页
目的:检测乳腺浸润性导管癌组织中c-FLIP(L)蛋白的表达,探讨c-FLIP(L)在乳腺癌中的临床病理意义,以及对乳腺癌细胞凋亡、增殖的影响。方法:收集116例乳腺浸润性导管癌标本,应用免疫组化技术分析c-FLIP(L)与乳腺癌临床病理因素的相关性。... 目的:检测乳腺浸润性导管癌组织中c-FLIP(L)蛋白的表达,探讨c-FLIP(L)在乳腺癌中的临床病理意义,以及对乳腺癌细胞凋亡、增殖的影响。方法:收集116例乳腺浸润性导管癌标本,应用免疫组化技术分析c-FLIP(L)与乳腺癌临床病理因素的相关性。以TUNEL标记肿瘤细胞凋亡指数,Ki-67标记增殖指数,分析c-FLIP(L)与细胞凋亡、增殖的相关性。结果:c-FLIP(L)蛋白定位于浸润性导管癌癌细胞胞浆中,ER、PR、Ki-67定位于肿瘤细胞胞核,Her-2定位于肿瘤细胞胞膜,TUNEL染色定位于肿瘤细胞胞核。c-FLIP(L)蛋白高表达与患者低年龄(<35岁)、绝经前、未发生远处转移、较早的pTNM分期(Ⅰ~Ⅱ期)密切相关:与家族史、手术方式、肿瘤大小、淋巴结转移、组织学分级和肿瘤复发等临床病理因素不存在显著相关性。在总病例中,ER阳性64例(55.17%),PR阳性43例(37.07%),Her-2阳性19例(16.38%)。c-FLIP(L)高表达与ER、PR之间存在显著相关性(P<0.05),与Her-2表达无关。c-FLIP(L)蛋白表达与乳腺癌凋亡指数正相关(r=0.544,P<0.05),虽然呈现c-FLIP(L)表达越高增殖指数越低的趋势,但二者之间相关系数无统计学意义(r=0.148,P>0.05)。结论:在乳腺癌中,c-FLIP(L)阳性表达提示患者较为良好的临床预后,该因子可能直接或间接参与肿瘤细胞凋亡过程,具有进一步研究的价值。 展开更多
关键词 c—FlIP(l) 乳腺癌 临床病理意义 凋亡
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复合频率直流逆变电路中L/C的域值计算与研究 被引量:3
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作者 魏丽君 陈一平 +1 位作者 戴涛 何华 《物探化探计算技术》 CAS CSCD 2010年第3期270-273,共4页
大功率复合频率电源是电法勘探中必需的信号源。大多数电法勘探仪器信号源的控制电路都采用大功率IGBT模块设计,因为IGBT模块具有输入阻抗高,速度快,通态压降低,热稳定性好,以及高电压和大电流的优点,但同时也存在控制电路较复杂,体积大... 大功率复合频率电源是电法勘探中必需的信号源。大多数电法勘探仪器信号源的控制电路都采用大功率IGBT模块设计,因为IGBT模块具有输入阻抗高,速度快,通态压降低,热稳定性好,以及高电压和大电流的优点,但同时也存在控制电路较复杂,体积大,抗干扰能力较差等缺点。这里重点介绍一种采用可控硅BT151(晶闸管)作为主要逆变器件,通过对L/C储能器件域值的合理选择,研究与设计了一套性能稳定,复合频率直流逆变电路,为电法勘探仪器采用大功率SCR器件提供了研究基础。该电路设计成果已成功的应用在国家"十一五"支撑课题项目中。 展开更多
关键词 复合频率 直流逆变电路 l/c的域值计算
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