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Letter from Li Peng Chairman of the Standing Committee of the National People's Congress, To China Society for Human Rights Studies 被引量:1
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作者 li peng 《The Journal of Human Rights》 2002年第1期1-1,共1页
China Society for Human Rights Studies, I would like to extend my warm greetings to the launch of your Human Rights magazine. Enjoying human rights fully is a lofty goal long pursued after by human race. Over the year... China Society for Human Rights Studies, I would like to extend my warm greetings to the launch of your Human Rights magazine. Enjoying human rights fully is a lofty goal long pursued after by human race. Over the years when they carried out revolution, construction and reforms, the Chinese people have struggled indomitably and strived incessantly to achieve this goal. Progress made in this regard has caught worldwide attention. When struggling for, safeguarding, promoting and developing human rights, the Chinese people have always combined the universality prin- 展开更多
关键词 Letter from Li Peng Chairman of the Standing Committee of the National People’s Congress To China Society for Human Rights Studies LI
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基于Penton蛋白禽腺病毒血清4型间接ELISA抗体检测方法的建立
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作者 李鹏 雷梦瑶 +9 位作者 冯丽丽 王振伟 管春晓 郑洪双 王俊茹 王利平 李炎锦 吴欣媛 刘兴友 金前跃 《河南农业科学》 北大核心 2024年第7期133-141,共9页
Penton蛋白是构成禽腺病毒血清4型(Fowl adenovirus serotype 4,FAdV-4)衣壳的主要结构蛋白,具备高度保守性与良好的免疫原性。以纯化的Penton蛋白为包被抗原,建立一种基于禽腺病毒血清4型Penton蛋白的间接ELISA抗体检测方法。结果显示,... Penton蛋白是构成禽腺病毒血清4型(Fowl adenovirus serotype 4,FAdV-4)衣壳的主要结构蛋白,具备高度保守性与良好的免疫原性。以纯化的Penton蛋白为包被抗原,建立一种基于禽腺病毒血清4型Penton蛋白的间接ELISA抗体检测方法。结果显示,Penton蛋白最佳包被质量浓度为2μg/mL,血清稀释倍数为200倍,酶标抗体稀释倍数为1∶5000,阳性临界值为0.222,敏感性可达到1∶6400,与鸡传染性支气管炎病毒、鸡传染性法氏囊病病毒、鸡传染性喉气管炎病毒均无交叉反应,特异性良好,批间批内重复性变异系数均<10%,在100份临床血清中阳性检出率为77%,与商品化试剂盒检出符合率可达98%。综上,建立的ELISA抗体检测方法可以用于禽腺病毒4型临床抗体检测。 展开更多
关键词 禽腺病毒血清4型 Penton蛋白 间接ELISA 抗体检测
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Ilizarov骨搬移联合抗生素骨水泥促进胫骨大段骨缺损的对接点愈合
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作者 张治博 王兆林 +5 位作者 王志刚 李朋 姜建浩 张锴 杨淑野 杜刚强 《中国组织工程研究》 CAS 北大核心 2025年第10期2038-2043,共6页
背景:Ilizarov骨搬移治疗开放性胫骨大段骨缺损十分有效,但仍有并发症,其中对接点愈合困难是治疗难点之一。目的:探讨Ilizarov骨搬移联合抗生素骨水泥对开放性胫骨大段骨缺损术后对接点愈合的影响。方法:选择2010年8月至2022年1月滨州... 背景:Ilizarov骨搬移治疗开放性胫骨大段骨缺损十分有效,但仍有并发症,其中对接点愈合困难是治疗难点之一。目的:探讨Ilizarov骨搬移联合抗生素骨水泥对开放性胫骨大段骨缺损术后对接点愈合的影响。方法:选择2010年8月至2022年1月滨州医学院附属医院收治的开放性胫骨大段(骨缺损> 4 cm)骨缺损患者51例,其中28例接受单纯Ilizarov骨搬移治疗(对照组),23例接受Ilizarov骨搬移联合抗生素骨水泥治疗(试验组)。统计比较两组患者外固定时间、骨愈合时间、骨愈合指数、骨搬移过程中的目测类比评分、末次随访时的骨缺损肢体功能、对接点愈合及并发症发生情况。结果与结论:(1)51例患者均获得完整随访,平均随访(22.53±5.77)个月,试验组患者外固定时间、骨愈合时间、骨愈合指数、术后感染率及对接点未愈合率均少于对照组(P <0.05),两组二期手术后6个月的目测类比评分、末次随访时的骨缺损肢体功能优良率比较差异无显著性意义(P> 0.05);(2)结果表明,相较于单纯的Ilizarov骨搬移治疗,Ilizarov骨搬移联合抗生素骨水泥治疗可促进开放性胫骨骨折对接点的愈合,提高骨愈合率。 展开更多
关键词 膜诱导成骨技术 骨搬移 对接点 骨愈合 胫骨开放性骨折 大段骨缺损
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Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement
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作者 HU Ze-bo liU Zhen +4 位作者 li peng GUO Hai-yan REN Xiao-hui HOU Hao HAO lian-hong 《China Ocean Engineering》 SCIE EI CSCD 2024年第3期394-407,共14页
In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference ef... In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined flume.The experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the risers.Three rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged downstream.The experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity increases.For the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced velocity.For the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’region.When the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer. 展开更多
关键词 marine riser vortex-induced vibration tandem arrangement ROUGHNESS interference effect
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Experimental Study on Vortex-Induced Vibration of Rough Risers with Coupling Interference Effect Under Side-by-Side Arrangement
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作者 HU Ze-bo liU Zhen +5 位作者 li peng GUO Hai-yan WANG Shu-bing REN Xiao-hui HOU Hao WANG Ye-shuo 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期18-28,共11页
A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterize... A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined flume.The roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the riser.Rough risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference effect.The experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency responses.In addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser. 展开更多
关键词 marine riser vortex-induced vibration side-by-side arrangement ROUGHNESS interference effect
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Exploring social-ecological system resilience in South China Karst:Quantification,interaction and policy implication
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作者 Tiantian Chen Yuxi Wang li peng 《Geography and Sustainability》 CSCD 2024年第2期289-301,共13页
China’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the environment.However,current understanding of its o... China’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the environment.However,current understanding of its outcomes on the social-ecological system(SES)remains limited.Therefore,taking the South China Karst as an example,a SES resilience evaluation index system was constructed followed by an exploratory spatial analysis,root mean square error,and Self-Organizing Feature Map to clarify the spatiotemporal changes and relationship of SES resilience,achieve the zoning of SES resilience and provide restoration measures.The results showed an upward trend in social resilience from 2000 to 2020,especially its subsystem of social development.Regional ecological resilience was stable,owing to a slightly declined ecosystem services and increased landscape pattern.Spatially,nearly half of the counties exhibited a distribution mismatch in SES resilience.There was an obvious inverted U-shaped relationship of SES resilience,indicating a clear threshold effect,and the constraint relation-ship of SES resilience eased over time,demonstrating the effectiveness of the ecological restoration program.GTGP played a positive role in reducing regional SES trade-off,but this positive effect was limited,reflecting the limitations of overemphasizing the conversion from farmland to forest and grassland.Regional SES resilience can be divided into four clusters,which were the key optimization zone for social system,the SES resilience safety zone,the key restoration zone for SES resilience,and the key optimization zone for ecological system.Adaptive adjustments for the GTGP in these zones should be taken to achieve maximum SES benefits in the future. 展开更多
关键词 SES resilience Trade-off CLUSTERING GTGP South China Karst
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Development and validation of a machine learning-based early prediction model for massive intraoperative bleeding in patients with primary hepatic malignancies
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作者 Jin li Yu-Ming Jia +4 位作者 Zhi-Lei Zhang Cheng-Yu liu Zhan-Wu Jiang Zhi-Wei Hao li peng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期90-101,共12页
BACKGROUND Surgical resection remains the primary treatment for hepatic malignancies,and intraoperative bleeding is associated with a significantly increased risk of death.Therefore,accurate prediction of intraoperati... BACKGROUND Surgical resection remains the primary treatment for hepatic malignancies,and intraoperative bleeding is associated with a significantly increased risk of death.Therefore,accurate prediction of intraoperative bleeding risk in patients with hepatic malignancies is essential to preventing bleeding in advance and providing safer and more effective treatment.AIM To develop a predictive model for intraoperative bleeding in primary hepatic malignancy patients for improving surgical planning and outcomes.METHODS The retrospective analysis enrolled patients diagnosed with primary hepatic malignancies who underwent surgery at the Hepatobiliary Surgery Department of the Fourth Hospital of Hebei Medical University between 2010 and 2020.Logistic regression analysis was performed to identify potential risk factors for intraoperative bleeding.A prediction model was developed using Python programming language,and its accuracy was evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Among 406 primary liver cancer patients,16.0%(65/406)suffered massive intraoperative bleeding.Logistic regression analysis identified four variables as associated with intraoperative bleeding in these patients:ascites[odds ratio(OR):22.839;P<0.05],history of alcohol consumption(OR:2.950;P<0.015),TNM staging(OR:2.441;P<0.001),and albumin-bilirubin score(OR:2.361;P<0.001).These variables were used to construct the prediction model.The 406 patients were randomly assigned to a training set(70%)and a prediction set(30%).The area under the ROC curve values for the model’s ability to predict intraoperative bleeding were 0.844 in the training set and 0.80 in the prediction set.CONCLUSION The developed and validated model predicts significant intraoperative blood loss in primary hepatic malignancies using four preoperative clinical factors by considering four preoperative clinical factors:ascites,history of alcohol consumption,TNM staging,and albumin-bilirubin score.Consequently,this model holds promise for enhancing individualised surgical planning. 展开更多
关键词 Primary liver cancer Intraoperative bleeding Machine learning Model
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光声成像评价靶向纳米粒联合LIFU对小鼠乳腺癌的治疗研究
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作者 黎鹏 方辉 +2 位作者 缪婉婷 范雪莲 董海霞 《医学影像学杂志》 2023年第12期2278-2282,共5页
目的制备叶酸修饰的红细胞膜伪装的载青蒿素(ART)多功能靶向仿生纳米粒,并应用光声成像(PAI)评价其联合低强度聚焦超声(LIFU)治疗小鼠乳腺癌的价值。方法选用聚乳酸-羟基乙酸共聚物(PLGA)作为纳米粒的载体材料,以全氟己烷(PFH)、Fe_(3)O... 目的制备叶酸修饰的红细胞膜伪装的载青蒿素(ART)多功能靶向仿生纳米粒,并应用光声成像(PAI)评价其联合低强度聚焦超声(LIFU)治疗小鼠乳腺癌的价值。方法选用聚乳酸-羟基乙酸共聚物(PLGA)作为纳米粒的载体材料,以全氟己烷(PFH)、Fe_(3)O_(4)、ART作为纳米粒的内核,再以红细胞膜(EM)包覆该纳米粒,最后EM表面经叶酸(FA)修饰为靶向分子,制备多功能靶向仿生纳米粒(PFH/ART@PLGA/Fe_(3)O_(4)-eFA)。激光扫描共聚焦显微镜(LSCM)观察纳米粒的FA连靶率。应用PAI观察纳米粒在小鼠乳腺癌组织内的靶向聚集程度。电感耦合等离子体发射光谱(ICP)检测纳米粒在血液中的代谢情况。纳米粒联合LIFU协同治疗肿瘤,并记录肿瘤大小变化。结果LSCM分析显示纳米粒mander重叠系数为83.7%。PAI结果显示合成的PFH/ART@PLGA/Fe_(3)O_(4)-eFA纳米粒在体外及体内均有良好的光学成像效果。PFH/ART@PLGA/Fe_(3)O_(4)-eFA组小鼠乳腺癌组织内光声信号强度显著高于PFH/ART@PLGA/Fe_(3)O_(4)组。ICP结果显示PFH/ART@PLGA/Fe_(3)O_(4)-eFA组血液中Fe2+浓度显著高于PFH/ART@PLGA/Fe_(3)O_(4)组;PFH/ART@PLGA/Fe_(3)O_(4)-eFA组小鼠肝脏及脾脏内的Fe2+显著低于PFH/ART@PLGA/Fe_(3)O_(4)组;且PFH/ART@PLGA/Fe_(3)O_(4)-eFA组小鼠乳腺癌组织内的Fe2+显著高于PFH/ART@PLGA/Fe_(3)O_(4)组。体内治疗结果显示,PFH/ART@PLGA/Fe_(3)O_(4)-eFA组小鼠乳腺癌体积显著小于其他各组。结论本研究成功制备包封PFH、Fe_(3)O_(4)、ART的多功能靶向仿生纳米粒,具有良好的体内外光声成像效果,初步证实可用于小鼠乳腺癌的靶向诊断,联合LIFU可以协同治疗小鼠乳腺癌。 展开更多
关键词 乳腺癌 青蒿素 纳米粒 低强度聚焦 超声诊断 光声成像
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Flexible Large-Area Graphene Films of 50-600 nm Thickness with High Carrier Mobility 被引量:4
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作者 Shiyu Luo li peng +13 位作者 Yangsu Xie Xiaoxue Cao Xiao Wang Xiaoting liu Tingting Chen Zhanpo Han Peidong Fan Haiyan Sun Ying Shen Fan Guo Yuxing Xia Kaiwen li Xin Ming Chao Gao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第5期1-14,共14页
Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and o... Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and optoelectronic devices to charge-stripping and electromagnetic shielding,etc.However,large-area flexible close-stacked graphene nanofilms with a wide thickness range have yet to be reported.Here,we report a polyacrylonitrile-assisted’substrate replacement’strategy to fabricate large-area free-standing graphene oxide/polyacrylonitrile nanofilms(lateral size~20 cm).Linear polyacrylonitrile chains-derived nanochannels promote the escape of gases and enable macro-assembled graphene nanofilms(nMAGs)of 50-600 nm thickness following heat treatment at 3,000℃.The uniform nMAGs exhibit 802-1,540 cm^(2)V-1s-1carrier mobility,4.3-4.7 ps carrier lifetime,and>1,581 W m^(-1)K^(-1)thermal conductivity(n MAG-assembled 10μm-thick films,mMAGs).nMAGs are highly flexible and show no structure damage even after 1.0×10^(5)cycles of folding-unfolding.Furthermore,n MAGs broaden the detection region of graphene/silicon heterojunction from near-infrared to mid-infrared and demonstrate higher absolute electromagnetic interference(EMI)shielding effectiveness than state-of-the-art EMI materials of the same thickness.These results are expected to lead to the broad applications of such bulk nanofilms,especially as micro/nanoelectronic and optoelectronic platforms. 展开更多
关键词 Flexible large-area graphene nanofilm High carrier mobility Mid-infrared detection Electromagnetic interference shielding Heat transfer
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适用于规划-运行两阶段的配电网可靠性等级划分及评估方法 被引量:1
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作者 李鹏 赵亚汝 +2 位作者 范须露 梁界飞 王加浩 《高电压技术》 EI CAS CSCD 北大核心 2024年第5期2042-2051,I0018,共11页
新型电力系统的快速建设与发展对配电网的可靠性评估提出了更高的要求。综合考虑配电网中终端用户差异化的可靠性需求和电网规划、运行两阶段的不同特点,提出了配电网可靠性等级划分方法和适用于规划-运行两阶段的配电网可靠性评估方法... 新型电力系统的快速建设与发展对配电网的可靠性评估提出了更高的要求。综合考虑配电网中终端用户差异化的可靠性需求和电网规划、运行两阶段的不同特点,提出了配电网可靠性等级划分方法和适用于规划-运行两阶段的配电网可靠性评估方法。首先,考虑用电性质、用户侧负荷特性等多方面因素,计及可靠性电价的影响,从系统侧、用户侧和供用电交互侧出发,建立了配电网供电可靠性评估指标体系;然后考虑终端用户用电需求的差异性,进行了配电网可靠性等级的划分;在此基础上,基于终端用户的差异化可靠性需求,提出了适用于规划-运行两阶段的配电网可靠性评估方法。最后进行算例分析,验证了所提划分方法的合理性和评估方法的有效性。 展开更多
关键词 可靠性评估 终端用户差异化需求 规划-运行两阶段 可靠性等级划分 熵权-层次分析法
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胸部CT图像质量评价与辐射剂量的临床应用研究 被引量:1
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作者 刘铁 李艳艳 +1 位作者 李鹏 王健 《影像技术》 CAS 2024年第1期19-23,38,共6页
目的:归纳和分析影响胸部CT图像质量的因素,进一步对照分析常规剂量组和低剂量组两组图像质量有无差异,以论证胸部CT低剂量检查的可行性。方法:选取150例胸部CT查体的患者,A组为常规剂量组,管电压120kV,管电流自动调节;B组为低剂量组,... 目的:归纳和分析影响胸部CT图像质量的因素,进一步对照分析常规剂量组和低剂量组两组图像质量有无差异,以论证胸部CT低剂量检查的可行性。方法:选取150例胸部CT查体的患者,A组为常规剂量组,管电压120kV,管电流自动调节;B组为低剂量组,管电压100kV,管电流自动调节。参照胸部CT的图像质量评价标准对常规剂量组和低剂量组图像质量进一步作出主观评价。对辐射剂量、信噪比等客观数据进行统计学处理,以P<0.05为差异有统计学意义。并与主观评价相比较。结果:主、客观评价两组图像质量均无统计学意义,A组辐射剂量与B组辐射剂量有统计学意义。结论:影响图像质量的因素包括患者的因素、设备的因素以及操作者的因素,胸部CT采用100kV低剂量检查可以作为常规扫描方案,获得的图像可以满足影像诊断的要求,具有可行性。 展开更多
关键词 胸部 计算机X线摄影 体层成像 图像质量 低剂量
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Comparison of efficacy of conbercept,aflibercept,and ranibizumab ophthalmic injection in the treatment of macular edema caused by retinal vein occlusion:a Meta-analysis 被引量:2
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作者 Qiu Xing Ya-Nan Dai +1 位作者 Xiao-Bo Huang li peng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第7期1145-1154,共10页
AIM:To evaluate and compare the anatomical and functional outcomes and negative effects of the three anti-vascular endothelial growth factor(VEGF)drugs in the treatment of macular edema(ME)due to retinal vein occlusio... AIM:To evaluate and compare the anatomical and functional outcomes and negative effects of the three anti-vascular endothelial growth factor(VEGF)drugs in the treatment of macular edema(ME)due to retinal vein occlusion(RVO)based on the evidence pooled from current clinical trials and observational studies.METHODS:A systematic literature search was conducted on nine online databases from inception until April 30,2022.The main endpoints were best corrected visual acuity(BCVA),central macular thickness(CMT),and adverse events(AEs).Cumulative Meta-analysis was conducted to synthesize the outcomes of the drugs.The retrieved data were analyzed using Stata software(version 12.0).RESULTS:A total of 20 studies comprising 1674 eyes met the inclusion criteria to the Meta-analysis.It was observed that conbercept and aflibercept had better visual acuity effects compared with ranibizumab at 1mo[weight mean difference(WMD)=-0.03,P=0.001;WMD=-0.05,P=0.019],but the effects were not different from that of ranibizumab at 6mo.Moreover,there was not statistically significant dif ference in the propor tion of patients gaining≥15 letters at 12-24mo between aflibercept and ranibizumab[odds ratio(OR)=1.16,P=0.427].Conbercept had higher mean CMT change effects at 1mo(WMD=-14.43,P=0.014)and 6mo(WMD=-35.63,P≤0.001)compared with ranibizumab.Meanwhile,the mean CMT change effects at 1mo(WMD=-10.14,P=0.170),6mo(WMD=-26.98,P=0.140)and 12-24mo(WMD=-12.34,P=0.071)were comparable among the groups.Similarly,AEs were not significantly different among the treatments(OR=0.75,P=0.305;OR=1.04,P=0.89).The stability of effect size of mean BCVA and CMT improved with the increase in sample size.Aflibercept and conbercept required fewer injections compared with ranibizumab.CONCLUSION:This is the first study to evaluate the efficacy and AEs of intravitreal administration of conbercept,ranibizumab,and aflibercept in the treatment of RVOME.Intravitreal aflibercept or conbercept results in better mean change in vision and CMT reduction compared with ranibizumab.Conbercept can be considered to be a promising and innovative drug with good anti-VEGF effects. 展开更多
关键词 anti-vascular endothelial growth factor conbercept AFLIBERCEPT RANIBIZUMAB macular edema retinal vein occlusion
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基于STM32的辨音识别系统的设计与应用 被引量:1
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作者 李棚 孔健 +2 位作者 叶飞 张明存 刘明明 《科学技术创新》 2024年第3期64-67,共4页
声音识别技术能够用于多种环境参数检测,本文采用STM32的DSP技术,对全向拾音器采集到环境声音进行快速傅里叶变换(FFT),获取待测声音的主频率和次频率,通过液晶屏显示采集信号的强度和主要频率分量。该设备能够有效对环境声音的主要参... 声音识别技术能够用于多种环境参数检测,本文采用STM32的DSP技术,对全向拾音器采集到环境声音进行快速傅里叶变换(FFT),获取待测声音的主频率和次频率,通过液晶屏显示采集信号的强度和主要频率分量。该设备能够有效对环境声音的主要参赛进行检测,在噪声检测和一般设备运行故障检测具有较高的适用性。 展开更多
关键词 STM32F103主控 快速傅里叶变换(FFT) 数字信号处理(DSP)
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Lipoprotein(a)and Benefit of PCSK9 Inhibition in Emergency Complex Higher-risk and Indicated Patients 被引量:1
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作者 Zhi-li JIN Tao HE +7 位作者 li peng Xiao-yan WU Di FAN Ming CHEN Yong-zhen FAN Yuan-lin GUO Zhi-bing LU Hai-rong WANG 《Current Medical Science》 SCIE CAS 2023年第6期1206-1212,共7页
Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially whe... Objective There is a large population of patients classified as complex higher-risk and indicated patients(CHIPs)in China with a poor prognosis.The treatment of these patients is complex and challenging,especially when acute cardiac events occur,such as acute coronary syndrome(ACS)or heart failure.Pharmacotherapy and some mechanical circulatory support(MCS)therapeutic devices can provide stable hemodynamic support for CHIPs-percutaneous coronary intervention(PCI).LDL-C is an important pathogenic factor in atherosclerosis,and the target of blood lipid control.Recent studies have revealed that lipoprotein(a)[Lp(a)],which is formed when a covalent bond between apolipoprotein(a)and apolipoprotein B-100 is made,produces an LDL-like particle.This particle is an independent risk factor for the development of atherosclerosis,and is closely correlated to stent thrombosis and restenosis.Furthermore,this requires active intervention.PCSK9 inhibitors have been used in lipid-lowering treatment,and preventing atherosclerosis.The present study explores the efficacy of PCSK9 inhibitors in CHIPs-ACS,and the association between the change in Lp(a)and survival after 2 years of follow-up.Methods The present real-world,prospective control study enrolled 321 CHIPs-ACS who underwent emergency PCI from August 2019 to November 2020,and these patients were followed up for 2 years.These patients were divided into two groups:PCSK9 group(n=161)given the combined PCSK9 inhibitor(140 mg of evolocumab every 2 weeks)and statins-based therapy,and SOC group(n=160)treated with statin-based lipid-lowering therapy alone.Then,the change in lipid index was measured,and the cardiovascular(CV)event recurrence rate was evaluated after one month and 2 years.Afterwards,the contribution of serum lipid parameters,especially the Lp(a)alteration,in patients with earlier initiation of the PCSK9 inhibitor to the CV outcome was analyzed.Results The LDL-C level was significantly reduced in both groups:52.3%in the PCSK9 group and 32.3%(P<0.001)in the SOC group.It is noteworthy that the Lp(a)level decreased by 13.2%in the PCSK9 group,but increased by 30.3%in the SOC group(P<0.001).Furthermore,the number of CV events was not significantly different between the PCSK9 and SOC groups after the 2-year follow-up period.In the PCSK9 group,the Lp(a)reduction was associated with the baseline Lp(a)levels of the patients(r2=−0.315,P<0.001).Moreover,the decrease in Lp(a)contributed to the decline in CV events in patients who received ACS CHIPs-PCI,and the decrease in Lp(a)level was independent of the LDL-C level reduction.Conclusion The early initiation of PCSK9 inhibitors can significantly reduce the LDL-C and Lp(a)levels in ACS CHIPs-PCI.However,further studies are needed to confirm whether PCSK9 inhibitors can reduce the incidence of CV disease in CHIPs. 展开更多
关键词 PCSK9 inhibitor complex higher-risk and indicated patients lipoprotein(a)level low-density lipoprotein cholesterol level 2-year cardiovascular event rate
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黄土高原径流侵蚀功率输沙模型的改进
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作者 于坤霞 李天毅 +4 位作者 贾路 李占斌 李鹏 丛佩娟 李斌斌 《农业工程学报》 EI CAS CSCD 北大核心 2024年第10期107-116,共10页
水土流失对流域生态危害严重,输沙量模拟和预测可以为流域水土流失防治提供依据,因此精确的输沙模型是流域水土流失治理的重要工具。为了精确模拟变化环境下黄土高原年输沙量,该研究基于黄土高原19个水文站的径流和输沙数据,通过随机森... 水土流失对流域生态危害严重,输沙量模拟和预测可以为流域水土流失防治提供依据,因此精确的输沙模型是流域水土流失治理的重要工具。为了精确模拟变化环境下黄土高原年输沙量,该研究基于黄土高原19个水文站的径流和输沙数据,通过随机森林变量重要性度量方法评估年径流侵蚀功率、淤地坝指数、淤地坝相对指数、归一化植被指数、不透水地面积等因子对流域年输沙量的影响,使用非线性最小二乘法估算年输沙模型参数,对比分析不同因子组合的年输沙模型精度,提出适用性较强的黄土高原年输沙模型,据此开展年输沙量变化贡献率分析。结果表明:1)以幂函数形式构建的仅含径流侵蚀功率单因子输沙模型精度与流域面积有显著的负相关关系,相关系数为-0.505(P<0.05),模型精度随着流域面积增大而下降,在面积大于7000 km^(2)的流域适用性较差;2)年径流侵蚀功率、淤地坝指数及不透水地面积因子组合建立的多因子年输沙模型在黄土高原适用性最佳,模型在率定期纳什效率系数平均值为0.84,均方根误差平均值为0.21亿t,在验证期纳什系数平均值为0.79,均方根误差平均值为0.27亿t。3)影响研究流域年输沙量变化的因素依次是:年径流侵蚀功率、不透水地面积和淤地坝指数。研究可以为黄土高原不同区域水土流失防治和生态治理工作提供理论支撑。 展开更多
关键词 侵蚀 径流 年输沙量 径流侵蚀功率 淤地坝指数 不透水地面积 贡献率
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“新型电力系统数字化关键技术综述”专辑评述
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作者 李鹏 刘念 +7 位作者 胡秦然 周全 李知艺 于浩 孙冰 严正 文福拴 薛禹胜 《电力系统自动化》 EI CSCD 北大核心 2024年第6期1-12,共12页
数字化是推动新型电力系统发展的重要动力,已成为广受学术界和产业界关注的热点技术。为此,《电力系统自动化》编辑部组织了“新型电力系统数字化关键技术综述”专辑,系统化介绍了新型电力系统数字化基础元件装备、边缘计算技术、通信... 数字化是推动新型电力系统发展的重要动力,已成为广受学术界和产业界关注的热点技术。为此,《电力系统自动化》编辑部组织了“新型电力系统数字化关键技术综述”专辑,系统化介绍了新型电力系统数字化基础元件装备、边缘计算技术、通信安全与防护、智能化调度决策等一系列技术成果,代表了本领域最新技术成果和先进经验。文中立足于新型电力系统数字化发展的整体趋势,对专辑论文按研究方向进行了系统性梳理,对其核心成果与观点进行了归纳总结,希望能够完整呈现专辑成果对新型电力系统数字化关键技术体系的支撑作用,为相关技术研究的进一步深化提供参考。 展开更多
关键词 新型电力系统 数字化 边缘计算 人工智能 信息安全 信息物理社会系统
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深空探测自主运行的一种可信性技术体系
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作者 党炜 骆军委 +8 位作者 郑作环 敖亮 李博 李鹏 熊盛阳 许鹏程 宋恒旭 胡剑桥 冯业为 《空间科学学报》 CAS CSCD 北大核心 2024年第2期228-240,共13页
未认知与不确定性是深空探测任务的基本特征.本文基于战略导向的体系化基础研究,建立了一种面向科学价值最大化的探测场景和以可靠性为核心技术基础的深空探测自主运行可信性技术体系.分析研究了深空探测场景下的可靠性概念;面向精确感... 未认知与不确定性是深空探测任务的基本特征.本文基于战略导向的体系化基础研究,建立了一种面向科学价值最大化的探测场景和以可靠性为核心技术基础的深空探测自主运行可信性技术体系.分析研究了深空探测场景下的可靠性概念;面向精确感知、最优计算、准确决策、快精准执行的目标要素,提出了深空探测自主运行的可信性体系框架以及“需求-认知-工程”总体技术架构;针对自主运行可信性的关键技术难点,开展了可靠性导向的多物理场、强耦合白盒建模,复杂网络故障传播机制分析,COTS元器件深空探测应用的高可靠保证,以及“模型+数据+知识”一体的融合机制分析等研究.对该技术体系的关键技术验证策略及其最小系统在卫星星座中的应用进行了验证,结果表明,所提出的技术体系具有较高的工程价值. 展开更多
关键词 深空探测 自主运行 可靠性 可信性 多物理场 复杂网络
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有机工质向心透平数值模拟及变工况内流特性研究
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作者 韩旭 李奇 +3 位作者 杨依栋 李鹏 刘树华 韩中合 《动力工程学报》 CAS CSCD 北大核心 2024年第2期260-269,共10页
基于国内外研究现状,分别对设计工况下和非设计工况下有机朗肯循环向心透平的工作状态进行了三维数值模拟。以透平功率、效率、反动度、静叶损失系数、动叶损失系数作为评价指标,分析了透平在非设计工况下的性能;同时开展了透平在非设... 基于国内外研究现状,分别对设计工况下和非设计工况下有机朗肯循环向心透平的工作状态进行了三维数值模拟。以透平功率、效率、反动度、静叶损失系数、动叶损失系数作为评价指标,分析了透平在非设计工况下的性能;同时开展了透平在非设计工况下流动状况的描述。结果表明:设计工况下透平输出功率为122.3 kW,透平等熵效率为83.54%;在非设计工况下,透平功率和效率在转速比为0.8~1.0时的增幅较大,透平反动度和静叶损失系数均与转速呈线性关系,而动叶损失系数在转速比为0.8~1.2时存在最小值;当转速低于设计转速时,在动叶前缘吸力面存在涡流,当转速高于设计转速时,涡流存在于动叶压力面的前缘,造成此现象的主要原因是动叶转速与静叶出口流速的周向分量之间存在差值。 展开更多
关键词 有机朗肯循环 向心透平 非设计工况 流动状况 数值模拟
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胆总管结石患者ERCP术后早期胆道感染的动态预测工具开发及验证
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作者 李鹏 梁超 +4 位作者 颜家凤 高春辉 马志杰 谢占涛 孙明洁 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第6期692-699,共8页
目的开发胆总管结石患者经内镜逆行性胰胆管造影术(ERCP)后发生早期胆道感染(PEEBI)的预测工具,以期辅助临床进行ERCP术前决策和术后早期个性化干预。方法采用观察性双向队列研究方法,选取某医院接受ERCP的胆总管结石住院患者,分别采用... 目的开发胆总管结石患者经内镜逆行性胰胆管造影术(ERCP)后发生早期胆道感染(PEEBI)的预测工具,以期辅助临床进行ERCP术前决策和术后早期个性化干预。方法采用观察性双向队列研究方法,选取某医院接受ERCP的胆总管结石住院患者,分别采用有向无环图(DAGs)和最小绝对收缩与选择算子法(LASSO)进行基于logistic回归的PEEBI预测,比较预测模型,并进行内外部验证。结果2020年1月1日—2023年9月30日,共纳入接受ERCP的胆总管结石患者2121例,其中77例(3.6%)发生了PEEBI,且主要集中在术后前2天(66.2%)。影响PEEBI的主要因素为非医源的患者相关因素,即糖尿病(OR=2.43,95%CI:1.14~4.85)、胆管恶性肿瘤(OR=3.95,95%CI:1.74~8.31)和十二指肠乳头憩室(OR=4.39,95%CI:1.86~9.52)。DAGs模型较LASSO模型的综合判别能力高3.0%(P=0.007),且DAGs模型外部验证中的区分性能(D=0.133,P=0.894)和校准性能(χ^(2)=5.499,P=0.703)均表现良好。结论本研究构建的DAGs模型具有良好的预测性能,临床可在该工具的协助下采取针对性的围手术期早期预防措施,以减少PEEBI的发生。 展开更多
关键词 胆总管结石 经内镜逆行性胰胆管造影术 胆道感染 有向无环图 预测
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中国锂矿的多旋回深循环内外生一体化成矿理论及其找矿应用
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作者 王登红 代鸿章 +9 位作者 刘善宝 王成辉 李建康 李鹏 陈郑辉 于扬 秦锦华 孙艳 娄德波 姚佛军 《地质学报》 EI CAS CSCD 北大核心 2024年第3期889-897,共9页
中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代... 中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代均有成矿潜力,可构成一个完整的多旋回成矿谱系。锂的“深循环”,一是锂深度参与成岩成矿的物质循环;二是需要一个“圈闭”的构造背景将锂“捕获”以避免其过度分散,锂从开始加入到岩浆与最终定位的深度之差,是硬岩型锂矿成矿的关键之一,压差越大越有利于伟晶岩型锂矿的形成。大量锂矿实例显示锂的物质循环是“内外生一体化”的统一过程,高海拔地区(山上)的含锂地质体(花岗岩类甚至直接就是含锂矿床)经风化剥蚀之后,可能成为沉积型锂矿的物质来源之一;而富含锂的沉积岩经过埋藏、变质、深熔也可以形成含锂的岩浆岩、伟晶岩。我国西部塔里木盆地、四川盆地、扎布耶盆地及东部的江汉盆地、吉泰盆地、周田盆地等大小不一的盆地均含锂,而其周边造山带中也不同程度发育硬岩型锂矿,这就为区域找矿指明了方向。“多旋回深循环内外生一体化”成锂理论是三稀矿产成矿理论的重要组成部分,为我国锂矿找矿工作提供了指导和借鉴,在甲基卡、可尔因、阿尔金、幕阜山等锂矿矿集区的找矿实践中发挥了积极作用。 展开更多
关键词 锂矿 构造运动 “多旋回深循环内外生一体化”成矿理论 找矿应用
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