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基于科研情境的单元复习教学——以“基因表达及其调控”为例

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生物学通报 2024年第4期59卷 37-42页

作者：李媛媛苏明学张红艳秦伟峰北京理工大学附属中学北京100089

通过对高三学生近视发生情况问卷调查,发现近视早发率与父母近视率之间具有相关性,鼓励学生提出问题“近视早发的原因是什么?”并围绕该问题展开思考与讨论。援引“实验性小鼠近视诱导”科研资料,组织学生设计并评价实验方案,锻炼科学... 详细信息

通过对高三学生近视发生情况问卷调查,发现近视早发率与父母近视率之间具有相关性,鼓励学生提出问题“近视早发的原因是什么?”并围绕该问题展开思考与讨论。援引“实验性小鼠近视诱导”科研资料,组织学生设计并评价实验方案,锻炼科学探究能力,体验科学研究的缜密;分析实验数据,进行逻辑推理,磨砺科学思维;深化“表观遗传”概念,重建基因、环境与性状三者之间的关系,养成爱眼、护眼的意识和习惯。

关键词：表观遗传单元复习生物学教学科研情境核心素养

基于MRI影像组学模型预测肺癌脑转移瘤EGFR基因突变

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磁共振成像 2024年第3期15卷 86-92页

作者：李保勋彭雨琴覃尉峰肖芳黎浩江陈俊伟李佳凝胡芷瑄毛家骥沈君中山大学孙逸仙纪念医院放射科广州510120 中山大学孙逸仙纪念医院深汕中心医院放射科汕尾516600 中国科学技术大学附属第一医院(安徽省立医院)放射科合肥230036 中山大学肿瘤防治中心放射科广州510060

目的探讨基于T2WI及增强T1WI(contrast enhanced T1WI,CE-T1WI)MRI的影像组学模型在术前无创预测肺癌患者脑转移瘤表皮生长因子受体(epidermal growth factor receptor,EGFR)突变的价值。材料与方法多中心回顾性分析2016年12月至2021年10月在中山大学孙逸仙纪念医院、中山大学肿瘤防治中心、安徽省立医院进行脑转移瘤手术切除并行EGFR基因检测的肺癌患者的临床及影像资料,共纳入103例患者(118个脑转移瘤),以中山大学肿瘤防治中心、安徽省立医院80例患者为训练集,共89个脑转移瘤(EGFR突变型49个,EGFR野生型40个),中山大学孙逸仙纪念医院23例患者为测试集,共29个脑转移瘤(EGFR突变型23个,EGFR野生型6个)。在CE-T1WI图像勾画脑转移瘤轮廓获取感兴趣体积(volume of interest,VOI),将CE-T1WI-VOI复制至配准后的T2WI图像获取脑转移瘤的T2WI-VOI,采用PyRadiomics软件从上述VOI提取脑转移瘤影像组学特征,采用mRMR和LASSO-logistics筛选影像组学特征,构建EGFR基因突变的预测模型,采用受试者工作特征(receiver operating characteristic,ROC)曲线的曲线下面积(area under the curve,AUC)评价影像组学模型对EGFR基因突变的预测效能。采用校准曲线和Hosmer-Lemeshow test(HL)评价模型校准度。采用决策曲线(decision curve analysis,DCA)评价影像组学模型预测EGFR基因突变状态的临床净获益。结果年龄、性别、病理类型、脑转移瘤数目、脑转移瘤直径在训练集和测试集中EGFR突变型及野生型的组间差异均无统计学意义(P>0.05)。在CE-T1WI及T2WI图像上共提取了3190个脑转移瘤的影像组学特征,最终筛选出了4个基于CE-T1WI图像和5个基于T2WI图像的影像组学特征构建预测EGFR基因突变状态的模型。该模型预测EGFR基因突变状态在训练集中AUC为0.828,准确度、敏感度、特异度分别为76.4%、81.6%、70.0%;在测试集中AUC值为0.783,准确度、敏感度、特异度分别为82.8%、95.7%、33.3%,均表现出较高的预测效能。影像组学模型训练集和测试集的校准曲线显示EGFR基因突变状态的预测概率与实际概率的一致性较好(HL>0.05)。DCA显示影像组学模型在13.8%~87.2%的阈值范围内具有较强的临床适用性。结论基于T2WI及CE-T1WI MRI构建的影像组学模型能够术前无创预测肺癌患者脑转移瘤EGFR基因突变状态。

关键词：肺癌脑转移瘤表皮生长因子受体影像组学磁共振成像

Reheat effect on the improvement in efficiency of the turbine driven by pulse detonation

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Defence technology 2024年第1期

作者： Junyu Liu Zhiwu Wang Zixu Zhang Junlin Li weifeng qin Jingjing Huang

来源：博看期刊评论

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基于保护校验数据的继电保护统计分析系统

电工技术 2024年第13期 150-153页

作者：孙运兵许勇斌屈天龙汪胜鑫段贤稳黄勇秦伟锋周利明大亚湾核电运营管理有限责任公司广东深圳518124 中广核核电运营有限公司广东深圳518124 北京博电国华新能源科技开发有限公司北京100176

为了解决电力系统中继电保护设备的统计效率问题,设计基于保护校验数据的继电保护统计分析系统。硬件方面,设计信息存储芯片、继电器驱动电路和继电保护示波器;软件方面,基于保护校验数据实现对继电保护信息数据的采样,然后在清洗数据... 详细信息

为了解决电力系统中继电保护设备的统计效率问题,设计基于保护校验数据的继电保护统计分析系统。硬件方面,设计信息存储芯片、继电器驱动电路和继电保护示波器;软件方面,基于保护校验数据实现对继电保护信息数据的采样,然后在清洗数据的基础上,设计实现继电保护统计分析流程。系统测试结果表明,该系统性能较优秀,时间开销较少,能满足继电保护统计分析需求。

关键词：保护校验数据继电保护统计分析系统设计

Constraints on the primordial curvature power spectrum by pulsar timing array data:a polynomial parameterization approach

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Communications in Theoretical Physics 2024年第1期76卷 96-104页

作者： qin Fei School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalarinduced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power *** effectively model this peak,we apply the Taylor expansion to parameterize *** the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data *** constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.

关键词： pulsar timing array scalar-induced gravitational waves inflation

Diversity and connectedness of brine shrimp viruses in global hypersaline ecosystems

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Science China(Life Sciences) 2024年第1期67卷 188-203页

作者： Xuan Dong Cixiu Li Yiting Wang Tao Hu Fan Zhang Fanzeng Meng Meirong Gao Xuekai Han Guohao Wang Jiahao qin Hans Nauwynck Edward CHolmes Patrick Sorgeloos Liying Sui Jie Huang weifeng Shi State Key Laboratory of Mariculture Biobreeding and Sustainable Goods Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesLaboratory for Marine Fisheries Science and Food Production ProcessesLaoshan LaboratoryKey Laboratory of Maricultural Organism Disease ControlMinistry of Agriculture and Rural AffairsQingdao Key Laboratory of Mariculture Epidemiology and BiosecurityQingdao 266071China Shandong Provincial Hospital Affiliated to Shandong First Medical University Jinan 250021China Key Laboratory of Emerging Infectious Diseases in Universities of Shandong Shandong First Medical University&Shandong Academy of Medical SciencesTaian 271000China Dalian Ocean University Dalian 116023China Asian Regional Artemia Reference Center Tianjin University of Science&TechnologyTianjin 300457China Ghent University Ghent 9000Belgium Sydney Institute for Infectious Diseases School of Medical SciencesThe University of SydneySydney 2006Australia Network of Aquaculture Centres in Asia-Pacific Bangkok 10900Thailand School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China

Brine shrimp(Artemia)has existed on Earth for 400 million years and has major ecological importance in hypersaline *** a crucial live food in aquaculture,brine shrimp cysts have become one of the most important aquatic products traded ***,our understanding of the biodiversity,prevalence and global connectedness of viruses in brine shrimp is still very limited.A total of 143 batches of brine shrimp(belonging to seven species)cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977–*** total,55 novel RNA viruses were identified,which could be assigned to 18 different viral families and related *** viruses were dsRNA viruses,16 were+ssRNA viruses,and 28 were−ssRNA *** analyses of the RNA-directed RNA polymerase(RdRp)showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and ***,most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche.A notable case was the novel brine shrimp noda-like virus 3,which shared 79.25%(RdRp)and 63.88%(capsid proteins)amino acid identity with covert mortality nodavirus(CMNV)that may cause losses in *** addition,both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses,particularly among Asia and Northern *** highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture *** broadly,these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.

关键词： brine shrimp Artemia virus diversity novel virus discovery global connectedness hypersaline ecosystem

Numerical study on the blocking effect of skin on Flash-Ball Impact and damage assessment

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Defence Technology（防务技术） 2024年第3期33卷 532-545页

作者： Dihua Ouyang Chunwei qin Xiaowen qin Qiantao Zhang Xingyu Liu Xi'an University of Architecture and Technology Xi'an 710055China Analysis and Testing Center Xi'an University of Architecture and TechnologyXi'an 710055China Engineering University of PAP Xi'an 710086China

To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy *** on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are *** corridor curve and the energy transfer and diffusion are analyzed and *** safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration ***,the safe shooting distance is *** results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response *** energy transfer and action time of medium and low-speed impact may cause greater *** fat layer is the largest energy absorption *** minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.

关键词： KIPs Blunt strike Biomechanical response Damage analysis

超高层双子塔面对面与角对角布局的气动特性与抗风性能比较

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振动与冲击 2023年第5期42卷 233-244页

作者：秦玮峰杨肖悦石俊阳谢霁明浙江大学建筑工程学院杭州310058

在风洞试验和数据分析的基础上,对面对面和角对角两种布局的双子塔建筑的气动特性和抗风性能进行了对比研究。研究的目的是为超高层双子塔的设计选型优化提供技术参考。结果表明,双塔建筑对风效应的性能取决于多个因素,包括双塔间距、... 详细信息

在风洞试验和数据分析的基础上,对面对面和角对角两种布局的双子塔建筑的气动特性和抗风性能进行了对比研究。研究的目的是为超高层双子塔的设计选型优化提供技术参考。结果表明,双塔建筑对风效应的性能取决于多个因素,包括双塔间距、结构动力特性、设计风速等。在较低的约化风速下,这两种布局的双子塔风效应没有明显差别。然而,当约化风速达到7以上后,双子塔将对塔楼的间距变得相当敏感,从而这两个不同的布局的抗风性能差别就会很明显。当双塔的相对间距在0.5左右或更窄时,角对角布局会导致严重的尾流激振,因此面对面布局的抗风性能相对较好。然而,随着间距的增加,角对角布局中的尾流激振会相应减弱。同时,角对角布局开始展示在借助气动干扰抑制涡激振动方面比面对面布局更为持续的优点,这导致角对角布局下的横风向动力响应比面对面布局显著减小。在相对间距为2时,角对角布局的风致倾覆力矩仅为面对面布局时的60%左右。

关键词：高层建筑双塔建筑建筑布局气动特性风致响应风洞试验

Limit state analysis of rigid retaining structures against seismically induced passive failure in heterogeneous soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1095-1105页

作者： Jianfeng Zhou Changbing qin College of Civil Engineering Huaqiao UniversityXiamen362021China School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing400045China

Soils are not necessarily uniform and may present linearly varied or layered characteristics,for example the backfilled soils behind rigid retaining *** the presence of large lateral thrust imposed by arch bridge,passive soil failure is possible.A reliable prediction of passive earth pressure for the design of such wall is challenging in complicated soil strata,when adopting the conventional limit analysis *** order to overcome the challenge for generating a kinematically admissible velocity field and a statically allowable stress field,finite element method is incorporated into limit analysis,forming finiteelement upper-bound(FEUB)and finite-element lower-bound(FELB)***-static,original and modified pseudo-dynamic approaches are adopted to represent seismic acceleration *** generating feasible velocity and stress fields within discretized elements based on specific criteria,FEUB and FELB formulations of seismic passive earth pressure(coefficient K_(P))can be derived from work rate balance equation and stress *** to an interior point algorithm,optimal upper and lower bound solutions are *** proposed FEUB and FELB procedures are well validated by limit equilibrium as well as lower-bound and kinematic *** studies are carried out to investigate the effects of influential factors on seismic K_(P).Notably,true solution of K_(P) is well estimated based on less than 5%difference between FEUB and FELB solutions under such complex scenarios.

关键词： Retaining wall Passive earth pressure Earthquakes Finite-element limit-analysis methods