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基于Simulink与FPGA的16APSK高速解调系统
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作者 夏创 周澳 +1 位作者 李劲 罗义军 《仪表技术与传感器》 北大核心 2025年第12期70-76,共7页
随着低轨卫星网络持续建设,需优化链路速率降低传输延迟,以实现卫星与地面网络的高效融合。同时针对低轨卫星高速运动引发的多普勒频移,基于Simulink,在环路带有延迟单元的情况下,完成高速并行16APSK解调系统的仿真。通过带有高速时钟的... 随着低轨卫星网络持续建设,需优化链路速率降低传输延迟,以实现卫星与地面网络的高效融合。同时针对低轨卫星高速运动引发的多普勒频移,基于Simulink,在环路带有延迟单元的情况下,完成高速并行16APSK解调系统的仿真。通过带有高速时钟的FPGA,实现了多路并行的系统硬件设计。在设计中提高数据量化精度,将解调后的信号导出至MATLAB,与前期仿真结果进行对比,验证了硬件设计的正确性。为测试系统性能,不断优化系统时序,并分析系统环路触发器级数对误码率及建立时间裕量的影响规律。 展开更多
关键词 SIMULINK 解调系统 FPGA 触发器
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Ancient genomic analysis of a Chinese hereditary elite from the Northern and Southern Dynasties 被引量:1
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作者 Yao Yu Xiaomin Yang +12 位作者 Daiyun liu Panxin Du e Hailiang Meng Zixiao Huang Jianxue Xiong Yi Ding Xiaoying Ren Edward Allen Hui Wang Sheng Han li jin Chuan-Chao Wang Shaoqing Wen 《Journal of Genetics and Genomics》 2025年第4期473-482,共10页
China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic ... China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic groups,with limited research on the genetic formation of the hereditary elite family,especially considering their abundant archaeological record and clear material identity.In this study,we obtain the ancient genome of a hereditary elite family,Gao Bin(高宾,503 AD–572 AD),at 0.6473-fold coverage with 475,132 single-nucleotide polymorphisms(SNPs)on the 1240k panel.His mitochondrial haplogroup belongs to Z4 and Y-haplogroup to O1a1a2b-F2444∗.The genetic profile of Gao Bin is most similar to that of the northern Han Chinese.He can be modeled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia,Korea,or the Mongolian Plateau.Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration. 展开更多
关键词 Ancient DNA Hereditary elite Population admixture Bohai Gao Branch Korean Goguryeo origin
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Thermal-responsive Photonic Crystals based on Physically Cross-linked Inverse Opal Nanocomposite Hydrogels 被引量:1
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作者 ZHENG Hang li jin +3 位作者 SONG Weizheng HE Guangyao WANG Yifeng CHEN Yanjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2021年第2期289-296,共8页
A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal... A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal template.In IONHPNIPAm,PNIPAm were physically cross-linked with two kinds of nanoparticles(carbon dots and laponite clays).The integration of carbon dots and laponite clays for physical crosslinking endowed IONHPNIPAm sufficient strength and self-healing property.IONHPNIPAm films can be completely peeled from the substrates to be utilized as an independent photonic crystal material.The structural color and optical diffraction of the IONHPNIPAm exhibits a rapid reversible change in response to external thermal stimuli due to its physical cross-linking feature.Moreover,the IONHPNIPAm shows clear fluorescence due to the introduction of carbon dots,which enables a convenient way for chemical detection(such as the detection of silver ions).This stimuli-responsive photonic crystal materials based on physically cross-linked inverse opal nanocomposite hydrogels with fast response and good mechanical stability are promising for applications in the fields of smart optical detectors,thermal-responsive sensors and chemical detectors. 展开更多
关键词 photonic crystals inverse opal physical cross-linking thermal-responsive nanocomposite hydrogel
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自主话语体系建设背景下的学前儿童语言教育研究
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作者 霍力岩 杜宝杰 +1 位作者 李金 魏灿星 《中华女子学院学报》 2026年第1期92-99,共8页
在当前西方语言发展理论及其教育模式影响下,我国学前儿童语言教育中本土文化语境与语言智慧未能得到足够重视,弱化了其在推动儿童文化认同与精神成长方面的作用。本研究以建立中国学前儿童语言教育的自主话语体系为目标,展开系统性的... 在当前西方语言发展理论及其教育模式影响下,我国学前儿童语言教育中本土文化语境与语言智慧未能得到足够重视,弱化了其在推动儿童文化认同与精神成长方面的作用。本研究以建立中国学前儿童语言教育的自主话语体系为目标,展开系统性的理论反思与实践探索。通过哲学分析,融合“言为心声”“文以载道”“道器合一”等传统思想,提出一种整合价值、实践与关系的语言教育观。借助批判性比较研究,对6份国内外早期语言发展纲要进行并置分析,揭示西方技能导向模式的局限以及中国文化回应型路径的必要性。在此基础上,构建了以价值取向、关键经验与发展路径为基本维度的理论框架,形成包含3个维度、10项核心要素及29项行为指标的完整体系。该体系并非静态行为清单,而是一个由文化价值引领、关键经验生成与实践路径支撑相互作用的动态文化生态系统,旨在为构建具有中国特色的学前儿童语言教育范式提供学理依据与实践参照。 展开更多
关键词 自主话语体系 学前儿童 语言教育 文化认同
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山东省14例输入性卵形疟原虫wallikeri亚种的鉴定 被引量:6
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作者 李瑾 魏庆宽 +8 位作者 徐超 肖婷 黄炳成 孔祥礼 王龙江 王用斌 许艳 尹昆 孙慧 《中国人兽共患病学报》 CAS CSCD 北大核心 2018年第11期991-995,共5页
目的对山东省14例输入性卵形疟原虫wallikeri亚种进行鉴定分析。方法收集14例输入性疟疾病例,进行快速疟疾诊断试纸条检测(RDT)、血涂片镜检、NP-1993常规巢式PCR鉴定和卵形疟原虫wallikeri(P.ovale wallikeri)亚种的特异性PCR检测。PC... 目的对山东省14例输入性卵形疟原虫wallikeri亚种进行鉴定分析。方法收集14例输入性疟疾病例,进行快速疟疾诊断试纸条检测(RDT)、血涂片镜检、NP-1993常规巢式PCR鉴定和卵形疟原虫wallikeri(P.ovale wallikeri)亚种的特异性PCR检测。PCR扩增产物测序后,进行Blast比对分析。结果 14例患者RDT检测结果:泛疟原虫(非恶性疟)阳性12例,阴性2例;镜检结果,13例卵形疟原虫,1例间日疟原虫;NP-1993常规巢式PCR结果,14例样本4种疟原虫引物扩增结果均为阴性。P.ovale wallikeri亚种的特异性PCR检测结果:14例样本均能扩增到P.ovale wallikeri亚种特异性条带780bp。Blast分析测序结果,检索结果为P.ovale wallikeri亚种。结论 14例镜检阳性、NP-1993常规巢式PCR检测阴性的输入性疟疾病例均确诊为P.ovale wallikeri亚种感染。 展开更多
关键词 疟疾 卵形疟原虫wallikeri亚种 巢式PCR
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New Opportunities,Challenges,and Strategies for Educational Evaluation Reform in the Era of Artificial Intelligence
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作者 li jin Hua Zhang 《Journal of Contemporary Educational Research》 2025年第1期66-73,共8页
Under the rapid impetus of artificial intelligence(AI)technology,human society is stepping into the age of intelligence at an unprecedented speed.A new generation of information technology such as AI is not only a new... Under the rapid impetus of artificial intelligence(AI)technology,human society is stepping into the age of intelligence at an unprecedented speed.A new generation of information technology such as AI is not only a new engine of economic development,but also a gas pedal of social development,which has had a profound impact on the field of education.In the face of the opportunities and challenges of the AI era,it is particularly urgent to build a scientific and reasonable education evaluation system.This paper combines the context of the times with the new technology of AI to discuss the opportunities,challenges,and implementation strategies of educational evaluation reform in the era of AI,with a view to providing references for the construction of the educational evaluation system and the development of high-quality education in the new era. 展开更多
关键词 Artificial intelligence Education evaluation reform New policy Formative evaluation Value-added evaluation Multiple evaluation
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A multi-ancestry GWAS meta-analysis of facial features and its application in predicting archaic human features
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作者 Siyuan Du Jieyi Chen +21 位作者 Jiarui li Wei Qian Sijie Wu Qianqian Peng Yu liu Ting Pan Yi li Sibte Syed Hadi jingze Tan Ziyu Yuan Jiucun Wang Kun Tang Zhuo Wang Yanqin Wen Xinran Dong Wenhao Zhou Andres Ruiz-linares Yongyong Shi li jin Fan liu Manfei Zhang Sijia Wang 《Journal of Genetics and Genomics》 2025年第4期513-524,共12页
Facial morphology,a complex trait influenced by genetics,holds great significance in evolutionary research.However,due to limited fossil evidence,the facial characteristics of Neanderthals and Denisovans have remained... Facial morphology,a complex trait influenced by genetics,holds great significance in evolutionary research.However,due to limited fossil evidence,the facial characteristics of Neanderthals and Denisovans have remained largely unknown.In this study,we conduct a large-scale multi-ethnic meta-analysis of the genome-wide association study(GWAS),including 9674 East Asians and 10,115 Europeans,quantitatively assessing 78 facial traits using 3D facial images.We identify 71 genomic loci associated with facial features,including 21 novel loci.We develop a facial polygenic score(FPS)that enables the prediction of facial features based on genetic information.Interestingly,the distribution of FPSs among populations from diverse continental groups exhibits relevant correlations with observed facial features.Furthermore,we apply the FPS to predict the facial traits of seven Neanderthals and one Denisovan using ancient DNA and align predictions with the fossil records.Our results suggest that Neanderthals and Denisovans likely share similar facial features,such as a wider but shorter nose and a wider endocanthion distance.The decreased mouth width is characterized specifically in Denisovans.The integration of genomic data and facial trait analysis provides valuable insights into the evolutionary history and adaptive changes in human facial morphology. 展开更多
关键词 Genome-wide association study Multi-ethnic meta-analysis Facial morphology Facial polygenic score Ancient DNA Archaic human
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Shock index and early warning score in liver cancer rupture shock
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作者 Ji-Fen Ma li jin +3 位作者 ling Sha Hong-Fang li Xiang-Yun Qian Hai-Yan Wang 《World Journal of Gastrointestinal Surgery》 2025年第10期246-254,共9页
BACKGROUND Primary liver cancer is a globally prevalent malignancy,with China accounting for approximately 55%of new cases,and is linked to hepatitis B,aflatoxin,and cirrhosis.Its rupture with hemorrhagic shock is a l... BACKGROUND Primary liver cancer is a globally prevalent malignancy,with China accounting for approximately 55%of new cases,and is linked to hepatitis B,aflatoxin,and cirrhosis.Its rupture with hemorrhagic shock is a lethal complication with high mortality,and traditional triage struggles with timely risk stratification,necessitating better tools,such as the integrated shock index(SI)-early warning score(EWS).AIM To study and analyze the combined effect of the SI and EWS in primary liver cancer patients with ruptured hemorrhage and shock.METHODS In total,118 patients who visited the Emergency Department of Nantong Third People's Hospital from January 2023 to December 2024 were selected and randomly divided into a control group(59 patients who received routine emergency treatment)and an observation group(59 patients who received condition assessment and intervention by combining the SI and EWS based on routine emergency treatment).The clinical treatment outcomes,respiratory function indicators,serological indicators,complications,and satisfaction with emergency intervention before and after the emergency intervention were compared between the two groups.RESULTS The emergency,triage,waiting,and hemostasis times,as well as hospital stay were shorter in the observation group than in the control group(P<0.05).After 48 hours of emergency intervention,blood oxygen saturation and partial pressure of oxygen in the observation group were higher than those in the control group(P<0.05).Seven days after emergency intervention,the hemoglobin,prealbumin,and albumin levels were higher in the observation group than in the control group(P<0.05).The complication rate in the observation group was 3.39%,lower than that in the control group(13.56%;P<0.05).Satisfaction with emergency intervention in the observation group was 94.92%,higher than 83.05%in the control group(P<0.05).CONCLUSION The combined application of the SI and EWS in patients with primary liver cancer rupture,hemorrhage,and shock can significantly shorten emergency treatment time,improve respiratory function and serological indicators,reduce the incidence of complications,and enhance patient satisfaction with emergency interventions,with higher clinical treatment efficiency and quality.Therefore,it is worthy of promotion and application. 展开更多
关键词 Primary liver cancer Rupture hemorrhage Shock index Early warning score system COMPLICATIONS
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Natural selection shaped the protective effect of the mtDNA lineage against obesity in Han Chinese populations
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作者 Ziwei Chen Lu Chen +8 位作者 jingze Tan Yizhen Mao Meng Hao Yi li Yi Wang jinxi li Jiucun Wang li jin Hong-Xiang Zheng 《Journal of Genetics and Genomics》 2025年第4期539-548,共10页
Mitochondria play a key role in lipid metabolism,and mitochondrial DNA(mtDNA)mutations are thus considered to affect obesity susceptibility by altering oxidative phosphorylation and mitochondrial function.In this stud... Mitochondria play a key role in lipid metabolism,and mitochondrial DNA(mtDNA)mutations are thus considered to affect obesity susceptibility by altering oxidative phosphorylation and mitochondrial function.In this study,we investigate mtDNA variants that may affect obesity risk in 2877 Han Chinese individuals from 3 independent populations.The association analysis of 16 basal mtDNA haplogroups with body mass index,waist circumference,and waist-to-hip ratio reveals that only haplogroup M7 is significantly negatively correlated with all three adiposity-related anthropometric traits in the overall cohort,verified by the analysis of a single population,i.e.,the Zhengzhou population.Furthermore,subhaplogroup analysis suggests that M7b1a1 is the most likely haplogroup associated with a decreased obesity risk,and the variation T12811C(causing Y159H in ND5)harbored in M7b1a1 may be the most likely candidate for altering the mitochondrial function.Specifically,we find that proportionally more nonsynonymous mutations accumulate in M7b1a1 carriers,indicating that M7b1a1 is either under positive selection or subject to a relaxation of selective constraints.We also find that nuclear variants,especially in DACT2 and PIEZO1,may functionally interact with M7b1a1. 展开更多
关键词 Mitochondrial DNA OBESITY Association analysis Natural selection Selective pressure
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Construction of problem list coding system for the whole life cycle of sea island supervision
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作者 WANG Na JI Dawei +5 位作者 li jin ZHAO jinxia ZHENG Fangyuan WANG jin TAN Lun GAO Yikang 《Marine Science Bulletin》 2025年第1期50-65,共16页
The code of the list of sea and island problems is the unique identification code of the regulatory files,which is accompanied by the whole life cycle of the regulatory"discovery,verification and disposal".S... The code of the list of sea and island problems is the unique identification code of the regulatory files,which is accompanied by the whole life cycle of the regulatory"discovery,verification and disposal".Standardized coding of problems found by supervision and tracking and recording the whole life cycle of supervision can quickly guide supervisors to find problems,identify problems,initiate responses and carry out follow-up disposal,which is a reflection of whole-process management of supervision.Combining with sea and island regulatory systems and mechanisms,combed the supervision business flow,divides the supervision link,based on the existing coding system,from the Angle of supervision refinement,puts forward a whole lifetime oriented regulatory system of sea and island issues list for coding,coding through to find and stop and disposal of the three links all process application scenarios,The implementation of the whole business"one code"association,the whole process of"one code"management,practice verification shows the effectiveness of the method,compared with the original coding rules for the supervision of all links and results reflect more intuitive,comprehensive,can be better applied to the practice of supervision. 展开更多
关键词 Marine supervision sea and island supervision coding fine regulation
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多发性骨髓瘤细胞中Blimp1、ATF4和CHOP的表达及阿司匹林对其表达的影响 被引量:5
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作者 刘红春 熊超 +4 位作者 耿杰 刘俊文 任珍珍 李晋 裴露 《中国实验血液学杂志》 CAS CSCD 北大核心 2020年第1期165-170,共6页
目的:探究多发性骨髓瘤(MM)患者骨髓单个核细胞中Blimp1、ATF4因子和CHOP蛋白的表达及阿司匹林对其表达的影响及意义。方法:采用Ficoll分离液分离60例初诊未经治疗的多发性骨髓瘤患者和30例骨髓相对正常者骨髓液中的单个核细胞,免疫磁... 目的:探究多发性骨髓瘤(MM)患者骨髓单个核细胞中Blimp1、ATF4因子和CHOP蛋白的表达及阿司匹林对其表达的影响及意义。方法:采用Ficoll分离液分离60例初诊未经治疗的多发性骨髓瘤患者和30例骨髓相对正常者骨髓液中的单个核细胞,免疫磁珠法分选CD138+的浆细胞并通过实时荧光定量PCR检测细胞中Blimp1,ATF4和CHOP mRNA表达水平。体外培养U266细胞,使用慢病毒感染细胞,采用实时荧光定量PCR检测不同分组细胞中Blimp1,ATF4和CHOP mRNA表达水平。用不同浓度的阿司匹林溶液(0、0.5、2.0和5.0mmol/L)体外分别刺激U266细胞24、48和72 h,采用CCK-8法检测阿司匹林对细胞的增殖活性的抑制作用。收集不同浓度的阿司匹林溶液刺激48 h后的U266骨髓细胞,实时荧光定量PCR检测各组细胞中Blimp1、ATF4和CHOP mRNA的表达水平。结果:与相对正常组浆细胞比较,MM患者CD138^+浆细胞中Blimp1 mRNA表达水平显著升高(8.040±1.878),ATF4和CHOP mRNA表达水平显著降低(0.735±0.089;0.837±0.062)(P<0.05)。体外培养U266细胞,相较空白对照组与阴性对照组,经LV-Blimp1-RNAi(40051-2)慢病毒表达载体感染后阳性实验组中Blimp mRNA的表达水平显著下调(0.637±0.021),ATF4和CHOP mRNA表达水平显著上调(1.452±0.027;1.721±0.038)(P<0.05)。CCK-8检测不同浓度阿司匹林刺激24、48和72 h后,U266细胞增殖活性降低,阿司匹林(0.5-5)mmol/L浓度范围内可显著抑制U266细胞的增殖活性,抑制作用随药物刺激时间的延长和刺激浓度的增加而增强(r24 h=0.986;r48 h=0.951;r72 h=0.954;r0.5=0.997;r2.5=0.997;r5.0=0.974)。不同浓度阿司匹林刺激48 h后,U266细胞中Blimp1 mRNA的表达水平随药物浓度升高而依次降低(r=-0.981),而ATF4和CHOP mRNA的表达水平随药物浓度升高而依次升高(rATF4=0.973;rCHOP=0.995)。结论:抑制多发性骨髓瘤细胞中Blimp1的表达,可促进ATF4和CHOP的表达。阿司匹林可通过下调骨髓瘤细胞中Blimp1表达和上调ATF4和CHOP的表达抑制骨髓瘤细胞的增殖活性,发挥抗肿瘤活性。 展开更多
关键词 Blimp1 多发性骨髓瘤 ATF4/CHOP 阿司匹林
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HO-1、LXA4、Apelin在糖尿病大鼠血清和视网膜中的表达特点 被引量:5
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作者 赵伟 朱向东 +1 位作者 李瑾 李丽华 《解剖学研究》 CAS 2019年第1期48-52,共5页
目的探究血红素氧和酶-1(HO-1)、脂质体A4(LXA4)、爱帕琳肽(Apelin)在糖尿病大鼠血清和视网膜中的表达特点。方法 Sprague-Dawley级大鼠60只随机分为4组,即对照组、模型组1(4周)、模型组2(12周)和模型组3(20周)。使用STZ法建模,并分别... 目的探究血红素氧和酶-1(HO-1)、脂质体A4(LXA4)、爱帕琳肽(Apelin)在糖尿病大鼠血清和视网膜中的表达特点。方法 Sprague-Dawley级大鼠60只随机分为4组,即对照组、模型组1(4周)、模型组2(12周)和模型组3(20周)。使用STZ法建模,并分别在建模后4周、12周和20周采集视网膜和血清标本。苏木精-伊红(HE)染色观察大鼠的视网膜形态,酶联免疫吸附试验(ELISA)检测血清中HO-1、LXA4、Apelin水平,使用Western blot和qRT-PCR检测视网膜组织中HO-1、LXA4、Apelin蛋白和mRNA水平。结果模型组1大鼠视网膜结构较正常,出现个别细胞水肿;模型组2视网膜细胞排列紊乱并出现层间偶伴融和;模型组3视网膜细胞排列疏松紊乱,并出现炎性浸润或水肿。模型组1和模型组2的大鼠血清和视网膜组织中HO-1水平显著高于对照组,而模型组3视网膜组织中HO-1水平显著低于对照组。与对照组相比,模型组大鼠血清和视网膜组织中LXA4显著降低而Apelin显著升高,模型组3的LXA4水平显著低于模型组1和模型组2,而Apelin显著高于模型组1和模型组2。视网膜组织中LXA4蛋白和mRNA与FPG和hs-CPR呈现负相关关系,Apelin与FPG和hs-CPR呈现正相关关系(P<0.05)。结论在随着糖尿病的发展,大鼠血清和组织中的HO-1呈现先上升后下降的趋势,LXA4水平逐渐下降而Apelin升高逐渐升高。并且视网膜组织中LXA4蛋白和mRNA与FPG和hs-CPR呈现负相关关系,Apelin与FPG和hs-CPR呈现正相关关系。 展开更多
关键词 糖尿病大鼠 糖尿病视网膜病变 血红素氧和酶-1 脂质体A4 爱帕琳肽
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多参数入射条件下分子碰撞对适应系数的影响
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作者 胡宇辉 陈琦 +3 位作者 张伟 江定武 李锦 乔晨亮 《物理学报》 北大核心 2026年第1期459-471,共13页
有效的气体-表面相互作用参数对准确预测气体在稀薄环境中的流动特性至关重要.然而微观分子碰撞模型中不同分子动力学模拟方法得到的适应系数差异很大.为了准确描述非平衡环境中分子碰撞与动量、能量适应的关系,本文采用分子动力学模拟... 有效的气体-表面相互作用参数对准确预测气体在稀薄环境中的流动特性至关重要.然而微观分子碰撞模型中不同分子动力学模拟方法得到的适应系数差异很大.为了准确描述非平衡环境中分子碰撞与动量、能量适应的关系,本文采用分子动力学模拟研究了氩与铂表面的相互作用.通过单个散射(SS)和连续散射(CS)方法系统地讨论了气-气碰撞对适应系数的影响.比较了两种方法在不同表面形态、表面温度、入射气体分子速度等影响因素下的气体-表面相互作用特性.得到了适应系数与表面温度、入射速度等参数之间的依赖关系.通过分析两种模拟方法的差异,揭示了多参数入射条件下适应系数变化的物理机制,为建立更精准的气体-表面相互作用模型提供了重要基础和依据. 展开更多
关键词 分子动力学 气体-表面相互作用 适应系数 表面形态
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PSO-LIBSVM在钾盐矿层识别中的应用研究 被引量:9
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作者 杨福强 陈科贵 +3 位作者 黄长兵 陈愿愿 李进 马小林 《地球科学进展》 CAS CSCD 北大核心 2019年第7期757-764,共8页
钾盐的紧缺严重制约了中国农业的发展,加大钾盐的勘探开发力度有助于提高我国钾盐的自给自足能力。四川盆地钾盐资源丰富,是我国目前重要的钾盐勘探开发研究区域之一。杂卤石作为四川盆地最重要的固态钾盐矿物,常夹杂在硬石膏、岩盐和... 钾盐的紧缺严重制约了中国农业的发展,加大钾盐的勘探开发力度有助于提高我国钾盐的自给自足能力。四川盆地钾盐资源丰富,是我国目前重要的钾盐勘探开发研究区域之一。杂卤石作为四川盆地最重要的固态钾盐矿物,常夹杂在硬石膏、岩盐和白云岩等岩层中。针对常规测井解释方法难以精确识别杂卤石的问题,因此,提出一种新的基于粒子群算法(PSO)优化的支持向量机(SVM)杂卤石识别方法开展四川盆地杂卤石的分类识别研究。以PSO和SVM理论为基础,结合测井解释方法,选择对杂卤石测井响应灵敏的有效数据作为输入样本,随机产生训练集和测试集,并采用PSO优选出径向基核函数参数,建立杂卤石分类预测模型。与录井结果对比,基于PSO的SVM模型识别准确率达到了97.5758%,在识别精度和速度上明显优于交叉验证方法优化的SVM模型。结果表明,该模型在四川盆地钾盐勘探中具有广阔的应用前景。 展开更多
关键词 四川盆地 测井数据 粒子群算法 支持向量机 杂卤石识别
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超高矿化度卤水基修井液研究与性能评价
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作者 贾文峰 宋佳俊 +3 位作者 李进 任日坤 陈雪 鲜成钢 《精细石油化工》 2026年第1期60-63,共4页
以超高矿化度玛湖地表盐水为溶剂,优选了增黏剂、降滤失剂、缓蚀剂等助剂,构建了一套适合玛湖1井区的超高矿化度玛湖盐水基修井液体系。该修井液配方为:240 mL玛湖盐水+60 mL清水+4%膨润土+0.5%PAC-HV+0.3%PAC-LV+1%重质超细碳酸钙(3 00... 以超高矿化度玛湖地表盐水为溶剂,优选了增黏剂、降滤失剂、缓蚀剂等助剂,构建了一套适合玛湖1井区的超高矿化度玛湖盐水基修井液体系。该修井液配方为:240 mL玛湖盐水+60 mL清水+4%膨润土+0.5%PAC-HV+0.3%PAC-LV+1%重质超细碳酸钙(3 000目)+0.6%ODD+0.2%NTA+重晶石。室内实验结果表明:该体系流变性能良好,FL_(API)滤失量为4.4 mL,防膨率达95.42%,腐蚀速率小于0.020 00 mm/a,且经100℃高温老化16 h后其流变性能、降滤失性能、防膨性能及缓蚀性能基本不变。 展开更多
关键词 流变性 滤失性 修井液 防膨性 卤水基 超高矿化度
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丘陵山地水稻机械化技术研究现状与展望 被引量:9
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作者 赵春江 马晨 +1 位作者 李瑾 王小萌 《农业工程学报》 北大核心 2025年第1期1-11,共11页
作为丘陵山地种植历史最久、种植面积最广、产量最高的农作物,水稻耕种收综合机械化水平的提升对于推进整个丘陵山地农业机械化全程全面高质量发展意义重大。该文以丘陵山地水稻机械化关键技术为“切口”,在梳理国内丘陵山地的特征与丘... 作为丘陵山地种植历史最久、种植面积最广、产量最高的农作物,水稻耕种收综合机械化水平的提升对于推进整个丘陵山地农业机械化全程全面高质量发展意义重大。该文以丘陵山地水稻机械化关键技术为“切口”,在梳理国内丘陵山地的特征与丘陵山地水稻机械化发展现状的基础上,围绕水稻耕、种、收等主要环节的生产机械化开展技术前沿与态势分析,剖析国内外水稻机械化技术装备研发差距,提出不同环节下国内丘陵山地水稻机械化发展面临的挑战,并展望未来丘陵山地水稻机械化发展态势,以期为推动水稻全程全域生产机械化水平提升、补齐丘陵山地农机化发展短板、建设现代农业强国提供新思路、新方向。研究表明:1)2022年国内丘陵山地水稻耕种收综合机械化率为80.8%,并且在不同的环节间、地区间发展不平衡不充分;2)与先进国家相比,国内的水稻耕种收机械研发与应用起步较晚、基础不牢、产品的综合性能不高,特别是针对丘陵山地的轻量、高效、高稳定性的水稻耕种收机械相对匮乏,发动机高功率低排放设计制造技术、刀具抗损降耗优化设计技术、车架轻量化设计技术等关键技术仍有待进一步攻克;3)轻量化、智能化、绿色化等是未来国内丘陵山地水稻生产作业装备发展方向与趋势。 展开更多
关键词 丘陵山地 水稻机械化 关键技术 主要挑战 未来趋势
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Cognitive deficits and Alzheimer-like neuropathological impairments during adolescence in a rat model of type 2 diabetes mellitus 被引量:12
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作者 li jin Yi-Pei li +4 位作者 Qiong Feng li Ren Fang Wang Guo-Jia Bo li Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第11期1995-2004,共10页
Numerous studies have shown that many patients who suffer from type 2 diabetes mellitus exhibit cognitive dysfunction and neuronal synaptic impairments. Therefore, growing evidence suggests that type 2 diabetes mellit... Numerous studies have shown that many patients who suffer from type 2 diabetes mellitus exhibit cognitive dysfunction and neuronal synaptic impairments. Therefore, growing evidence suggests that type 2 diabetes mellitus has a close relationship with occurrence and progression of neurodegeneration and neural impairment in Alzheimer's disease. However, the relationship between metabolic disorders caused by type 2 diabetes mellitus and neurodegeneration and neural impairments in Alzheimer's disease is still not fully determined. Thus, in this study, we replicated a type 2 diabetic animal model by subcutaneous injection of newborn Sprague-Dawley rats with monosodium glutamate during the neonatal period. At 3 months old, the Barnes maze assay was performed to evaluate spatial memory function. Microelectrodes were used to measure electrophysiological function in the hippocampal CA1 region. Western blot assay was used to determine expression levels of glutamate ionotropic receptor NMDA type subunit 2 A(GluN2A) and GluN2B in the hippocampus. Enzyme-linked immunosorbent assay was used to determine levels of interleukin-1β, tumor necrosis factor α, and interleukin-6 in the hippocampus and cerebral cortex, as well as hippocampal amyloid beta(Aβ)1-40 and Aβ_(1-42) levels. Our results showed that in the rat model of type 2 diabetes mellitus caused by monosodium glutamate exposure during the neonatal period, latency was prolonged and the number of errors increased in the Barnes maze. Further, latency was increased and time in the escape platform quadrant shortened. Number of times crossing the platform was also reduced in the Morris water maze. After high frequency stimulation of the hippocampus, synaptic transmission was inhibited, expression of GluN2A and GluN2B were decreased in the hippocampus, expression of interleukin 1β, interleukin 6, and tumor necrosis factor α was increased in the hippocampus and cortex, and levels of Aβ_(1-40) and Aβ_(1-42) were increased in the hippocampus. These findings confirm that type 2 diabetes mellitus induced by neonatal monosodium glutamate exposure results in Alzheimer-like neuropathological changes and further causes cognitive deficits and neurodegeneration in young adulthood. 展开更多
关键词 nerve regeneration type 2 diabetes mellitus Alzheimer's disease monosodium glutamate neonatal period cognitive deficits HYPERGLYCEMIA HYPERINSULINEMIA insulin resistance neural regeneration
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High strength and ductility Mg-8Gd-3Y-0.5Zr alloy with bimodal structure and nano-precipitates 被引量:15
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作者 Xiaoxiao Wei li jin +4 位作者 Fenghua Wang jing li Nan Ye Zhenyan Zhang Jie Dong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第9期19-23,共5页
To resolve the strength-ductility trade-off problem for high-strength Mg alloys,we prepared a high performance Mg-8Gd-3Y-0.5 Zr(wt%)alloy with yield strength of 371 MPa,ultimate tensile strength of 419MPa and elongati... To resolve the strength-ductility trade-off problem for high-strength Mg alloys,we prepared a high performance Mg-8Gd-3Y-0.5 Zr(wt%)alloy with yield strength of 371 MPa,ultimate tensile strength of 419MPa and elongation of 15.8%.The processing route involves extrusion,pre-deformation and aging,which leads to a bimodal structure and nano-precipitates.Back-stress originated from the deformationincompatibility in the bimodal-structure alloy can improve ductility.In addition,dislocation density in coarse grains increased during the pre-deformation strain of 2%,and the dislocations in coarse grains can promote the formation of chain-like nano-precipitates during aging treatment.The chain-like nanoprecipitates can act as barriers for dislocations slip and the existing mobile dislocations enable good ductility. 展开更多
关键词 Magnesium alloy Strength-ductility trade-off Bimodal structure Back-stress Chain-like intragranular nano-precipitates
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Homozygous loss-of-function mutations in FSIP2 cause male infertility with asthenoteratospermia 被引量:10
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作者 Wangjie liu Huan Wu +13 位作者 li Wang Xiaoyu Yang Chunyu liu Xiaojin He Weiyu li Jiajia Wang Yujie Chen Hongyan Wang Yang Gao Shuyan Tang Shenmin Yang li jin Feng Zhang Yunxi Cao 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2019年第1期53-56,共4页
Male infertility, as a major issue of human reproduction health, prevents successful natural conception. Asthenoteratospermia mainly presents one or multiple anomalies in head, neck and tail of spermatozoa, and impair... Male infertility, as a major issue of human reproduction health, prevents successful natural conception. Asthenoteratospermia mainly presents one or multiple anomalies in head, neck and tail of spermatozoa, and impairs sperm function and motility (Coutton et al., 2015). Recurrent abnormalities of the fibrous sheath lead to multiple morphological abnormaliries of the sperm flagella (MMAF), which is a quite frequent type of asthenoteratospermia in male infertility (Chemes et al., 1987;Ben Khelifa et al, 2014). 展开更多
关键词 Male INFERTILITY REPRODUCTION health RECURRENT ABNORMALITIES
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Facile preparation of sepiolite@LDH composites for the visible-light degradation of organic dyes 被引量:8
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作者 li jin Hong‐Yan Zeng +5 位作者 Sheng Xu Chao‐Rong Chen Heng‐Zhi Duan jin‐Ze Du Guo Hu Yun‐Xin Sun 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第11期1832-1841,共10页
Sepiolite@LDH(Sep@LDH)composites were designed and prepared based on the assembly of layered double hydroxides(LDH)on acidified sepiolites(Sep)for the simultaneous photocatalytic degradation of methyl orange(MO)and me... Sepiolite@LDH(Sep@LDH)composites were designed and prepared based on the assembly of layered double hydroxides(LDH)on acidified sepiolites(Sep)for the simultaneous photocatalytic degradation of methyl orange(MO)and methylene blue(MB).The structure,morphology,texture,optical properties,and photocatalytic performance of the prepared Sep@LDH were studied in detail.Among the Sep@LDH composites,Sep4@LDH(4.0 g Sep)exhibited the highest photocatalytic activity under visible‐light irradiation,which could be attributed to its large surface area,high crystallinity,and plentiful active sites on its surface.The photodegradation of the dyes followed a pseudo first‐order kinetic model(Langmuir‐Hinshelwood model),indicating that the copious and homogeneous active sites on the surface of the composites contributed to the high photocatalytic activity.The photodegradation mechanism was studied by examining the active species(^-OH,h+,and·O2^-anions)using appropriate scavengers.It was found that·OH radicals played a critical role in the photocatalytic process of MO and MB,where the generation of·OH radicals occurred on the electron/hole(e^-/h+)pairs on the surface of the Sep@LDH composites. 展开更多
关键词 Layered double hydroxides SEPIOLITE Photocatalytic performance Water treatment Nano materials
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