检索结果-南通市图书馆

Journal of Integrative Agriculture 2024年第9期23卷 2955-2969页

作者： Xin Dong Baole Li zhenzhen yan Ling Guan Shoubing Huang Shujun Li Zhiyun Qi Ling Tang Honglin Tian Zhongjun Fu Hua yang Chongqing Academy of Agricultural Sciences Chongqing 401329China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Heat stress is a major constraint to current and future maize production at the global *** and female reproductive organs both play major roles in increasing seed set under heat stress at flowering,but their relative contributions to seed set are *** this study,a 2-year field experiment including three sowing dates in each year and 20 inbred lines was *** set,kernel number per ear,and grain yield were all reduced by more than 80%in the third sowing dates compared to the first sowing *** viability,silk emergence ratio,and anthesis-silking interval were the key determinants of seed set under heat stress;and their correlation coefficients were 0.89^(***),0.65^(***),and-0.72^(***),*** pressure deficit(VPD)and relative air humidity(RH)both had significant correlations with pollen viability and the silk emergence *** RH can alleviate the impacts of heat on maize seed set by maintaining high pollen viability and a high silk emergence *** a warming climate from 2020 to 2050,VPD will decrease due to the increased *** on their pollen viability and silk emergence ratios,the 20 genotypes fell into four different *** group with high pollen viability and a high silk emergence ratio performed better under heat stress,and their performance can be further improved by combining the improved flowering pattern traits.

关键词： maize pollen viability silk emergence heat stress relative humidity

鲁氏接合酵母对高盐和高温胁迫响应的差异性与共性分析

在线全文

学校读者我要写书评

暂无评论

食品科学 2024年第2期45卷 79-88页

作者：刘梦奇闫珍珍胡娜陈雄李欣湖北工业大学生物工程与食品学院发酵工程教育部重点实验室湖北省工业微生物重点实验室湖北省工业发酵协同创新中心湖北武汉430068

针对高温(40℃)和高盐(18%NaCl)逆境设计了最低营养需求全合成培养基,分析了鲁氏接合酵母(Zygosaccharomyces rouxii)在长期逆境下生长的营养需求差异,重点解析了酵母细胞从生长适应期到对数生长初期阶段有机酸、氨基酸和糖类物质的代... 详细信息

针对高温(40℃)和高盐(18%NaCl)逆境设计了最低营养需求全合成培养基,分析了鲁氏接合酵母(Zygosaccharomyces rouxii)在长期逆境下生长的营养需求差异,重点解析了酵母细胞从生长适应期到对数生长初期阶段有机酸、氨基酸和糖类物质的代谢及基因表达差异。研究结果显示,遭遇高盐压力的鲁氏接合酵母细胞更需要外源氨基酸,而补充维生素和氨基酸有助于缓解酵母细胞的高温压力。鲁氏接合酵母针对高盐和高温逆境采用了差异明显的有机酸、氨基酸和糖代谢策略。MSN4(逆境转录子基因)和HOG1(高渗调控蛋白基因)响应高盐,而HSF1(热激调控蛋白基因)和SOD1(超氧化物歧化酶基因)对高温响应。本研究加深了对耐盐鲁氏接合酵母耐温机制的理解,有助于双抗新能力酿造酵母菌株的研制。

关键词：鲁氏接合酵母高盐逆境高温逆境全合成培养基营养需求代谢差异基因表达

数字化时代高职院校信息技术基础课程的教学改革研究

在线全文

学校读者我要写书评

暂无评论

信息与电脑 2024年第15期36卷 228-230页

作者：闫珍珍李幸刚郑州职业技术学院河南郑州450000 平顶山职业技术学院河南平顶山467000

高职院校的信息技术基础课程是学生需要学习的公共基础课程,其目的在于通过对这门课程的学习,提高学生的计算机操作能力,促进数字化创新,为学生的职业发展奠定基础。本文以数字化时代为背景,旨在通过对高职院校信息技术基础课程教学的... 详细信息

高职院校的信息技术基础课程是学生需要学习的公共基础课程,其目的在于通过对这门课程的学习,提高学生的计算机操作能力,促进数字化创新,为学生的职业发展奠定基础。本文以数字化时代为背景,旨在通过对高职院校信息技术基础课程教学的现状进行分析,探讨该课程教学改革的措施,为相关教育工作者提供参考。

关键词：数字化时代高职院校信息技术基础教学改革

3D Path prediction of moving objects in a video-augmented indoor virtual environment

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2021年第12期14卷 1818-1834页

作者： Hongdeng Jian Xiangtao Fan zhenzhen yan Mingrui Huang Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Augmented virtual environments(AVE)combine real-time videos with 3D scenes in a Digital Earth System or 3D GIS to present dynamic information and a virtual scene *** can provide solutions for continuous tracking of moving objects,camera scheduling,and path planning in the real *** paper proposes a novel approach for 3D path prediction of moving objects in a video-augmented indoor virtual *** study includes 3D motion analysis of moving objects,multi-path prediction,hierarchical visualization,and path-based multi-camera *** results show that these methods can give a closed-loop process of 3D path prediction and continuous tracking of moving objects in an *** path analysis algorithms proved accurate and time-efficient,costing less than 1.3 ms to get the optimal *** experiment ran a 3D scene containing 295,000 triangles at around 35 frames per second on a laptop with 1 GB of graphics card memory,which means the performance of the proposed methods is good enough to maintain high rendering efficiency for a video-augmented indoor virtual scene.

关键词： Augmented virtual environment(AVE) Digital Earth platform indoor moving object 3D path prediction

Spectral element analysis on the characteristics of seismic wave propagation triggered by Wenchuan M_s8.0 earthquake

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2009年第6期52卷 764-773页

作者： yan zhenzhen ZHANG Huai yanG ChangChun SHI YaoLin Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Laboratory of Computational Geodynamics Graduate University of Chinese Academy of SciencesBeijing 100049China

The 2008 Wenchuan earthquake occurred in an active earthquake zone, i.e., Longmenshan tectonic zone. Seismic waves triggered by this earthquake can be used to explore the characteristics of the fault rupture process and the hierarchical structure of the Earth's interior. We employ spectral element method incorporated with large-scale parallel computing technology, to investigate the characteristics of seismic wave propagation excited by Wenchuan earthquake. We calculate synthetic seismograms with one-point source model and three-point source model respectively. The AK135 model is employed as a prototype of our numerical global Earth model. The Earth's ellipticity, Earth’s medium attenuation, and topography data are taken into consideration. These wave propagation processes are simulated by solving three-dimensional elastic wave governing equations. Three-dimensional visualization of our numerical results displays the profile of the seismic wave propagation. The three-point source, which is proposed from the latest investigations through field observation and reverse estimation, can better demonstrate the spatial and temporal characteristics of the source rupture process than the one-point source. We take comparison of synthetic seismograms with observational data recorded at 16 observatory stations. Primary results show that the synthetic seismograms calculated from three-point source agree well with the observations. This can further reveal that the source rupture process of Wenchuan earthquake is a multi-rupture process, which is composed by at least three or more stages of rupture processes.

关键词： Wenchuan earthquake spectral element method numerical simulation global seismic wave parallel computing

A genetic algorithm based hybrid non-orthogonal multiple access protocol

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2022年第1期28卷 1-9页

作者： yan zhenzhen yanG Mao yan Zhongjiang School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072P.R.China

Both high-dense wireless connectivity and ultra-huge network capacity are main challenges of next generation broadband *** one of its key promising technologies,non-orthogonal multi-ple access(NOMA)scheme can solve those challenges and meet those needs to some extent,in the way that different user equipments(UEs)multiplex on the same *** around the world have presented numerous NOMA *** those,sparse code multiple access(SC-MA)technology is a typical NOMA *** supports scheduled access and random access which can be called granted access and grant-free access *** resources allocated to granted UEs and grant-free UEs are strictly *** order to improve resource utilization,a hybrid non-orthogonal multiple access scheme is *** allows granted UEs and grant-free UEs sharing the same resource unit in terms of fine-grained *** the basis,a resource allocation method is further brought forward based on genetic *** optimizes resource allocation of all UEs by mapping resource distribution issue to an optimization *** throughputs of four meth-ods,simulation results demonstrate the proposed genetic algorithm has better throughput gain.

关键词： non-orthogonal multiple access(NOMA) resource allocation sparse code multiple access(SCMA) genetic algorithm hybrid non-orthogonal multiple access

Study on excitation of the two-tone acoustic characteristic of the chime bell of Marquis Yi of Zeng by finite element method

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2007年第16期52卷 2167-2173页

作者： ZHANG Huai yan zhenzhen yanG ChangChun SHI YaoLinit Graduate University of Chinese Academy of Sciences Beiiinq 100049 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The bronze chime bells of Marquis Yi of Zeng are precious cultural relics of China. The bells have a two-tone acoustic characteristic,i.e.,striking different parts of the bell generates different tones. In this study,we use a finite element method to simulate the propagation of elastic waves and the generation of free oscillations of the bell. Vibrations with different spectral characteristics can be obtained by striking different parts of the chime bell of Marquis Yi of Zeng. By the observation of the vibration de-sign and through spectral analysis,we further help the understanding of the two-tone acoustic char-acteristic of the chime bell of Marquis Yi of Zeng.

关键词：曾侯乙乐器钟声有限元法双声学特性

负载银纳米颗粒小球藻的明胶/聚乙二醇水凝胶的性能及其对小鼠全层皮肤缺损感染创面愈合的作用

在线全文

学校读者我要写书评

暂无评论

中华烧伤与创面修复杂志 2024年第1期40卷 33-42页

作者：严珍珍王雨翔张停琳荀竞男马艺程季超高洁肖仕初海军军医大学第一附属医院烧伤外科上海200433 海军军医大学第一附属医院临床研究中心上海200433

目的探讨负载银纳米颗粒(AgNP)小球藻的明胶/聚乙二醇水凝胶(以下简称复合水凝胶)的性能及其对小鼠全层皮肤缺损感染创面愈合的作用。方法该研究为实验研究。制备单纯明胶/聚乙二醇水凝胶(以下简称单纯水凝胶)和复合水凝胶,大体观察2种... 详细信息

目的探讨负载银纳米颗粒(AgNP)小球藻的明胶/聚乙二醇水凝胶(以下简称复合水凝胶)的性能及其对小鼠全层皮肤缺损感染创面愈合的作用。方法该研究为实验研究。制备单纯明胶/聚乙二醇水凝胶(以下简称单纯水凝胶)和复合水凝胶,大体观察2种水凝胶分别在55、37℃以及808 nm近红外光照射下的外观和可注射性;采用电子万能试验机测试2种水凝胶在室温下的拉应力-应变性能、压应力-应变性能以及复合水凝胶在80%最大压应力下的循环压应力-应变性能。分别于磷酸盐缓冲液(PBS)、单纯水凝胶和复合水凝胶中滴加金黄色葡萄球菌或大肠埃希菌菌液。取部分滴加了金黄色葡萄球菌或大肠埃希菌菌液的复合水凝胶,予近红外光照射5 min。将各样品孵育6 h后,采用稀释涂布平板法检测并计算2种细菌培养24 h的死亡率(样本数为5)。取海军军医大学第一附属医院泌尿外科收治的1名6岁健康男童包皮环切术后废弃包皮组织,采用酶解法提取分离原代人成纤维细胞(HFb),常规培养至第3~6代,用于后续细胞实验。制备终质量浓度分别为100.0、50.0、25.0、12.5、0 mg/mL的复合水凝胶浸提液,用其培养HFb,培养24 h后采用细胞计数试剂盒8检测细胞增殖活性,样本数为3。取20只6~8周龄雌性C57BL/6J小鼠,在每只鼠背部制作1个全层皮肤缺损创面,在创面上涂抹金黄色葡萄球菌菌液进行感染。将感染小鼠按照随机数字表法分为空白对照组、单纯水凝胶组、复合水凝胶组、联合处理组,每组5只小鼠,分别采用PBS、单纯水凝胶、复合水凝胶、复合水凝胶+光照(用波长808 nm近红外光照射5 min)处理其创面。于伤后0(首次处理创面后即刻)、3、7、14 d,大体观察各组小鼠创面渗出及愈合情况并计算伤后7、14 d的创面愈合率,样本数为5。伤后14 d,行苏木精-伊红染色观察小鼠创面组织病理学变化。结果单纯水凝胶和复合水凝胶在55℃时均为溶液状态,降温到37℃后均呈凝胶态;近红外光照射2种水凝胶后,仅复合水凝胶升温,可再次回到溶液状态,即具有可注射性。复合水凝胶的最大拉应力可达301.42 kPa,对应的应变为87.19%;最大压应力可达413.79 kPa,对应的应变为91.67%,均与单纯水凝胶的拉伸和压缩性能相近。复合水凝胶经过10次压缩循环后,其最大压应力仍可达第1次压应力的84.1%。培养24 h,金黄色葡萄球菌经单纯水凝胶处理后的死亡率明显高于经PBS处理后(P<0.05);大肠埃希菌和金黄色葡萄球菌仅经复合水凝胶处理后的死亡率均明显高于经单纯水凝胶处理后(P<0.05);大肠埃希菌和金黄色葡萄球菌经复合水凝胶+光照处理后的死亡率均明显高于仅经复合水凝胶处理后(P<0.05)。培养24 h,与用终质量浓度0 mg/mL复合水凝胶浸提液培养相比,用终质量浓度25.0、50.0 mg/mL复合水凝胶浸提液培养的HFb的增殖活力均明显增强(P<0.05),用终质量浓度100.0 mg/mL复合水凝胶浸提液培养的HFb的增殖活力明显减弱(P<0.05)。伤后0、3 d,空白对照组、单纯水凝胶组小鼠创面中的脓性分泌物均较多,复合水凝胶组小鼠创面中仅有少量渗出液,而联合处理组小鼠创面中未见明显感染。伤后7、14 d,单纯水凝胶组小鼠创面愈合率均明显高于空白对照组(P<0.05),复合水凝胶组小鼠创面愈合率均明显高于单纯水凝胶组(P<0.05),联合处理组小鼠创面愈合率均明显高于复合水凝胶组(P<0.05)。伤后14 d,空白对照组小鼠创面有较多的炎症细胞浸润、未见新生的上皮层;单纯水凝胶组小鼠创面中新生上皮长度短,且存在少量炎症细胞;复合水凝胶组小鼠创面中有连续的新生上皮形成,以及大量未成熟的肉芽组织;联合处理组小鼠创面有连续的新生上皮形成,未成熟肉芽组织较少。结论制备的复合水凝胶具有良好的温敏性、光热性和可注射性,以及良好的机械性能、抗菌性能和生物相容性,可促进小鼠全层皮肤缺损感染创面愈合。

关键词：水凝胶纳米粒子细菌感染光热治疗绿色合成银纳米创面修复

克拉霉素联合布地奈德治疗慢性鼻-鼻窦炎不伴鼻息肉患者的临床疗效及不良反应分析

在线全文

学校读者我要写书评

暂无评论

中国医学文摘（耳鼻咽喉科学） 2024年第4期39卷 66-68,94页

作者：张丽梅王丹严珍珍甘肃省酒泉市人民医院甘肃酒泉735000

目的探究慢性鼻-鼻窦炎不伴鼻息肉患者采用克拉霉素联合布地奈德治疗的效果及不良反应。方法纳入酒泉市人民医院2021年3月至2022年3月收治的慢性鼻-鼻窦炎不伴鼻息肉患者80例为研究对象,随机分2组,每组40例。对照组和观察组分别采用克... 详细信息

目的探究慢性鼻-鼻窦炎不伴鼻息肉患者采用克拉霉素联合布地奈德治疗的效果及不良反应。方法纳入酒泉市人民医院2021年3月至2022年3月收治的慢性鼻-鼻窦炎不伴鼻息肉患者80例为研究对象,随机分2组,每组40例。对照组和观察组分别采用克拉霉素治疗和克拉霉素联合布地奈德治疗,比较两组的疗效、上皮损伤程度、炎症因子水平和不良反应。结果观察组总有效率为97.50%,高于对照组的75.00%(P0.05)。结论慢性鼻-鼻窦炎不伴鼻息肉患者采用克拉霉素联合布地奈德治疗,能有效减轻上皮损伤和炎症反应,效果显著,安全性高。

关键词：慢性鼻-鼻窦炎布地奈德克拉霉素上皮损伤不良反应

Vertical accuracy assessment of freely available digital elevation models over low-lying coastal plains

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2016年第3期9卷 252-271页

作者： Xiaoping Du Huadong Guo Xiangtao Fan Junjie Zhu zhenzhen yan Qin Zhan Key Laboratory of Digital Earth Institute of Remote Sensing and Digital Earth(RADI)Chinese Academy of Sciences(CAS)BeijingChina University of Chinese Academy of Sciences BeijingChina

The frequency of coastal flood damages is expected to increase significantly during the twenty-first century as sea level rises in the coastal *** digital elevation model(DEM)data describing coastal topography are essential for assessing future flood-related damages and understanding the impacts of sea-level *** Shuttle Radar Topography Mission(SRTM)and Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM)are currently the most accurate and freely available DEM ***,an accuracy assessment specifically targeted at DEMs over low elevation coastal plains is *** present study focuses on these areas to assess the vertical accuracy of SRTM and ASTER GDEM using Ice,Cloud,and land Elevation Satellite,Geoscience Laser Altimeter System(ICESat/GLAS)and Real Time Kinematic(RTK)Global Positioning System(GPS)field survey *** findings show that DEM accuracy is much better than the mission specifications over coastal *** addition,optical remote sensing image analysis further reveals the relationship between DEM vertical accuracy and land cover in these *** study provides a systematic approach to assess the accuracy of DEMs in coastal zones,and the results highlight the limitations and potential of these DEMs in coastal applications.

关键词： DEM ICESat/GLAS SRTM ASTER GDEM elevation accuracy coastal flood modelling