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Study on Effect of Iron in Anther Media of Early Japonica Rice in Cold Region 被引量:2
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作者 张兰民 黄晓群 +2 位作者 王瑞英 刘传雪 关世武 《Agricultural Science & Technology》 CAS 2008年第6期64-67,共4页
In this study, through vitro culturing anthers of 7 F1 progenies of early Japonica rice in cold region on medium with different Fe2+ contents, it was found that Fe2+ content generated greater impacts on the induction ... In this study, through vitro culturing anthers of 7 F1 progenies of early Japonica rice in cold region on medium with different Fe2+ contents, it was found that Fe2+ content generated greater impacts on the induction rate and green plantlet differentiation. The result demonstrated that if Fe2+ increased from 32 to 40 mg/kg, the induction rate of early Japonica rice anther culture in N6 culture media was more then 1.4 times higher than that in N6 culture media containing 5.6 mg/kg Fe2+. In this concentration range, the induction rate increased with the increase of Fe2+ content, while if the concentration was over this concentration range, the induction rate decreased with the increase of Fe2+, showing single peak distribution. When the Fe2+ was 40 mg/kg in differentiation medium, the differentiation rate decreased dramatically. The green plantlet differentiations of callus which were induced on culture media containing 32-40 mg/kg Fe2+ were different, when they were cultured on MS culture media, and 85.7% materials could increase green plantlet productivity to about 7.8%. Therefore, increasing Fe2+in induction media properly could increase anther culture efficiency of early Japonica rice in cold region. 展开更多
关键词 early JAPONICA rice in COLD region ANTHER CULTURE Medium IRON EFFECT
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First record of Early Cretaceous pterosaur from the Ordos Region, Inner Mongolia,China 被引量:2
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作者 Shu-an Ji 《China Geology》 2020年第1期1-7,共7页
A new dsungaripterid pterosaur,Ordosipterus planignathus gen.et sp.nov.,is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi,Ordos Region,Inner Mongolia,Chi... A new dsungaripterid pterosaur,Ordosipterus planignathus gen.et sp.nov.,is established on the incomplete articulated lower jaws from the Lower Cretaceous Luohandong Formation in Otog Qi,Ordos Region,Inner Mongolia,China.It differs from other dsungaripterids mainly by having broad and low dentary at and just behind the mandibular symphysis,flat dentary dorsal plane forming the distinct lateral ridge with the curved dentary lateral side,and lower alveoli arranged along the dentary dorsolateral margin with wide spacing that increases from rostral to caudal.It represents the first diagnostic pterosaur from the Ordos Region in Inner Mongolia,and further enlarges the geographical distribution of the family Dsungaripteridae from northwestern China(together with western Mongolia)to central North China. 展开更多
关键词 PTEROSAURIA early Cretaceous Ordos region Inner Mongolia China
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Late Carboniferous-Early Permian Volcanic Event Deposits and Stratigraphic Correlation in Shandong Province and Its Adjacent Regions 被引量:3
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作者 Zhong Rong, Institute of Geomechanics, Chinese Academy of Geological Sciences, BeijingSun Shanping and Fu Zeming China University of Geosciences, Beijing Xu Niansheng, Xu Heling and Zhong Rong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第4期380-394,453,共16页
Deposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong Province and its adjacent regions. They show certain ... Deposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong Province and its adjacent regions. They show certain temporal-spatial distribution characteristics. Volcanic fragments were probably derived from two different volcanic sources north and south of the North China Platform, while the magma of the two volcanic sources was probably derived from the lower crust. A new stratigraphic correlation scheme is put forward for the Benxi and Taiyuan Formations in this region on the basis of previous biostratigraphic work with the regionally widespread volcanic event layers as the marker bed for the isochronous stratigraphic correlation on a super-regional scale and in conjunction with the maximum transgressive event layers. 展开更多
关键词 volcanic event deposits Late Carboniferous-early Permian Benxi and Taiyuan Formations stratigraphic correlation volcanic source Shandong Province and its adjacent regions
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Study on the Occurrence and Epidemic Regularity and Region Division of Rice Blast in Nanchong City 被引量:1
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作者 彭昌家 白体坤 +2 位作者 丁攀 冯礼斌 杨宇衡 《Agricultural Science & Technology》 CAS 2016年第4期927-937,共11页
With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systemati... With the aim to improve the level of monitoring and warning as well as the comprehensive control of rice blast disease, and to feasibly reduce the disease threat in Nanchong City, the methods of GPS and GIS, systematical monitoring and field survey, rice blast resistance identification, physiologic races of rice blast monitoring, and meteorological data analysis were performed to study the occurrence and epidemic region division, precise demarcation and occurrence and epidemic regularity of rice blast in Nanchong City. This study first completed the epidemic region division and precise demarcation; first clarified the initial affection(beginning period) locations, occurrence characteristics, epidemic trends and characteristics; explicated the existence of four epidemic peak periods of rice blast in the field, where the damage areas of first peak period played a decisive role during the blast epidemic years; in late May, the cumulative occurrence areas and annual occurrence areas presented higher positive correlation with the correlation coefficient of 0.817;and established a prediction model of occurrence areas per year based on the disease field rate at the end of boot stages and the diseased plant rate at dough stages. The results of investigation on the impact factors investigation of blast disease in Nanchong in recent years suggested that the internal causes were the decrease or loss of blast resistance of the rice cultivars, as well as the increase of physiological races with strong resistance to rice blast and the emergence of new virulent physiologic varieties; the external causes were suitable temperature, too much rainy, and sunlight shortage. Between 2010 and 2015, the short-term forecast accuracy for rice blast in Nanchong was up to 100%, and medium-and long-term forecast accuracy was also up to 98% and 95%, respectively, which increased by 5-15% than that before 1997, thereby making the control effect of rice blast in Nanchong increased by 15-30%. 展开更多
关键词 Rice Rice blast region division Occurrence characteristics Epidemic regularity early warning level
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Tectonics and Topography of the Tibetan Plateau in Early Miocene 被引量:2
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作者 WU Zhenhan YANG Yan +2 位作者 Patrick J. BAROSH WU Zhonghai ZHANG Yaoling 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第2期410-424,共15页
Early Miocene stratigraphy,major structural systems,magmatic emplacement,volcanic eruption,vegetation change and paleo-elevation were analyzed for the Tibetan Plateau after regional geological mapping at a scale of 1... Early Miocene stratigraphy,major structural systems,magmatic emplacement,volcanic eruption,vegetation change and paleo-elevation were analyzed for the Tibetan Plateau after regional geological mapping at a scale of 1:250,000 and related researches,revealing much more information for tectonic evolution and topographic change of the high plateau caused by Indian-Asian continental collision.Lacustrine deposits of dolostone,dolomite limestone,limestone,marl,sandstone and conglomerate of weak deformation formed extensively in the central Tibetan Plateau,indicating that vast lake complexes as large as 100,000-120,000 km2 existed in the central plateau during Early Miocene.Sporopoilen assemblages contained in the lacustrine strata indicate the disappearance of most tropical-subtropical broad-leaved trees since Early Miocene and the flourishing of dark needle-leaved trees during Early Miocene.Such vegetation changes adjusted for latitude and global climate variations demonstrate that the central Tibetan Plateau rose to ca.4,000-4,500 m and the northeastern plateau uplifted to ca.3,500-4,000 m before the Early Miocene.Intensive thrust and crustal thickening occurred in the areas surrounding central Tibetan Plateau in Early Miocene,formed Gangdise Thrust System (GTS) in the southern Lhasa block,Zedong-Renbu Thrust (ZRT) in the northern Himalaya block,Main Central Thrust (MCT) and Main Boundary Thrust (MBT) in the southern Himalaya block,and regional thrust systems in the Qaidam,Qilian,West Kunlun and Songpan-Ganzi blocks.Foreland basins formed in Early Miocene along major thrust systems,e.g.the Siwalik basin along MCT,Yalung-Zangbu Basin along GTS and ZRT,southwestern Tarim depression along West Kunlun Thrust,and large foreland basins along major thrust systems in the northeastern margin of the plateau.Intensive volcanic eruptions formed in the Qiangtang,Hoh-Xil and Kunlun blocks,porphyry granites and volcanic eruptions formed in the Nainqentanglha and Gangdise Mts.,and leucogranites and granites formed in the Himalaya and Longmenshan Mts.in Early Miocene.The K2O weight percentages of Early Miocene magmatic rocks in the Gangdise and Himlayan Mts.are found to increase with distance from the MBT,indicating the genetic relationship between regional magmatism and subduction of Indian continental plate in Early Miocene. 展开更多
关键词 Lacustrine deposits vast lakes elevation change regional thrust system early Miocene Tibetan Plateau
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Analysis of climatic features and major meteorological disasters over the Three Gorges Region of the Yangtze River Basin in 2021 被引量:2
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作者 Tong Cui Xianyan Chen +3 位作者 Xukai Zou Qiang Zhang Hongling Zeng Linhai Sun 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第6期57-63,共7页
Based on daily observation data in the Three Gorges Region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main mete... Based on daily observation data in the Three Gorges Region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main meteorological factors in 2021,as well as the year’s climatic events and meteorological disasters.The 2021 average temperature was 0.2℃above the 1991-2020 average and the 13 th-warmest year since 1961.Seasonally,winter and autumn were both warmer than usual.The annual mean precipitation was 12.8%above normal,and most regions experienced abundant rainfall throughout the year.The seasonal variation in precipitation was significant and the TGR had a wetter-than-normal spring and summer.The number of rainstorm days was higher than normal;the wind speed was above normal;and the relative humidity was higher than normal.In terms of rain acidity,2021 was tied with 2020 as the lowest since 1999.From mid-September to early October 2021,the TGR experienced exceptional high-temperature weather,which was driven by abnormal activity of mid-and high-latitude atmospheric circulation over the Eurasian continent and the western Pacific subtropical high(WPSH).In addition,a strong blocking high over the Ural Mountains accompanied by intense mid-latitude westerly winds prevented cyclonic disturbances from extending to the subtropical region.As a result,under the combined effect of the weaker-than-normal cold-air activities and the anomalous WPSH,the TGR experienced extreme high-temperature weather during early autumn 2021. 展开更多
关键词 Three Gorges region Climatic anomaly Weather and climate events Extremely warm early autumn
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Probabilistic earthquake early warning times in Fujian Province 被引量:1
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作者 Hongcai Zhang Xing Jin 《Earthquake Science》 2013年第1期33-41,共9页
Earthquake early warning (EEW) systems are a new and effective way to mitigate the damage associated with earthquakes. A prototype EEW system is currently being constructed in the Fujian Province, a region along the... Earthquake early warning (EEW) systems are a new and effective way to mitigate the damage associated with earthquakes. A prototype EEW system is currently being constructed in the Fujian Province, a region along the Southeast coast of China. It is anticipated that the system will be completed in time to be tested at the end of this year (2013). In order to evaluate how much advanced warning the EEW system will be able to provide different cities in Fujian, we established an EEW information release scheme based on the seismic monitoring stations distributed in the region. Based on this scheme, we selected 71 historical earthquakes. We then obtained the delineation of the region's potential seismic source data in order to estimate the highest potential seismic intensities for each city as well as the EEW system warning times. For most of the Fujian Province, EEW alarms would sound several seconds prior to the arrival of the destructive wave. This window of time gives city inhabitants the opportunity to take protective measures before the full intensity of the earthquake strikes. 展开更多
关键词 Earthquake early warning systems Lead time Fujian region
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Banded Iron Formations (BIFs) and Associated Sediments Do Not Reflect the Physical and Chemical Properties of Early Precambrian Seas
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作者 Zeev Lewy 《International Journal of Geosciences》 2012年第1期226-236,共11页
Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin.... Ring-in-ring structures in Australian Early Precambrian banded iron formation (BIF) were identified as bubbling mud wavelets, which lithified during temporary exposure, contradicting the alleged BIF deep ocean origin. Least altered BIFs consist of alternating chert laminae with, and without iron oxides (or carbonates). They were precipitated during on-and-off periods of ferrous iron oxidation controlled by microbial oxygenic photosynthetic activity during solar illumination, which stopped during darkness as characterizing the Polar Regions, thus forming genuine annual varves. This polar environment is further corroborated by the magnetite-hematite-magnetite microcrystal layers in the iron-rich laminae reflecting mid-spring-summer-autumn changes in solar radiation, and by diamictite at the end of the sequence deposited from melting glaciers when the continental plate shifted to lower latitudes. BIF sequences in various countries comprise evaporates. They attest to intensive evaporation of the warm hydrothermal solution in restricted shallow lakes under the freezing dry climate up to silica (geyserite) precipitation referred to chert. The existence of oceans, mid-ocean-ridges and island arcs during the Early Precambrian results from the misinterpreted oceanic origin of BIFs and the Phanerozoic occurrences of the associated mafic-ultramafic basalt flows (Greenstone Belt). 展开更多
关键词 early PRECAMBRIAN BIF NON-MARINE POLAR regions Physical and Chemical Control
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The Features of Dasyclad Algae and the Dasycladaceae Fossils in Jiaonan Region
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作者 Zhang Songmei Cheng Liren Liu Diantao 《Global Geology》 2000年第2期156-160,共5页
The features of all fossil assemblage from Jiaonan region are equal to those of the plant in the forth stage or the fifth stage. The time of samples association of Dasycladaceae algae in Jiaonan area should be in earl... The features of all fossil assemblage from Jiaonan region are equal to those of the plant in the forth stage or the fifth stage. The time of samples association of Dasycladaceae algae in Jiaonan area should be in early Cretaceous period. The group of Dasycladaceae algae in Jiaonan region is marine plant, and belongs to the Tethys paleobotanic province. They began to distribute westward and eastward from Triassic period in a radiating way. And the geographical position was in tropical or subtropical zoneat that time. 展开更多
关键词 Dasycladaceae Jiaonan region early CRETACEOUS
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南秦岭早古生代碱性岩地球化学特征及其成因机制:研究进展与展望 被引量:1
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作者 赖绍聪 杨航 张方毅 《地质学报》 EI CAS CSCD 北大核心 2024年第3期799-828,共30页
南秦岭地区在早古生代经历了大规模且持续性的碱性岩浆活动,其丰富的碱性岩石记录为探索深部地幔物质组成、壳内岩浆演化过程以及地球动力学演化机制提供了珍贵的地质载体。文章基于团队近期对于区域上典型碱性岩的地球化学分析结果和... 南秦岭地区在早古生代经历了大规模且持续性的碱性岩浆活动,其丰富的碱性岩石记录为探索深部地幔物质组成、壳内岩浆演化过程以及地球动力学演化机制提供了珍贵的地质载体。文章基于团队近期对于区域上典型碱性岩的地球化学分析结果和成因机制探讨,旨在对南秦岭早古生代碱性岩浆的源区和演化过程进行全面地约束。南秦岭早古生代碱性岩石类型主要包括一套成分从碱性玄武质向粗面质变化,呈双峰式分布的碱性火山-侵入岩组合,以及少量与碱性硅酸岩(角闪辉石岩、正长岩)-碳酸岩共生杂岩体。岩相学、年代学和地球化学证据显示这些碱性岩具有相同的地幔源区,其中演化程度较低的镁铁质端元记录了南秦岭早古生代交代岩石圈地幔的部分熔融事件,交代介质主要为硅酸盐熔体。演化程度较高的碱性岩端元(粗面-正长岩、碳酸岩)来源于初始镁铁质组分的岩浆分异过程,其中粗面-正长岩类主要受到以长石和单斜辉石为主的分离结晶作用控制。中生代热液交代过程主要记录在北大巴山东部和武当地块西南缘的早古生代碱性岩体中,热液交代作用促进了碳酸岩杂岩体中稀土元素的富集成矿。副矿物年代学和独居石Nd同位素特征反映了热液可能形成于岩体本身的再活化事件,晚三叠世秦岭地区的造山运动可能对此过程具有促进作用。 展开更多
关键词 早古生代 南秦岭 碱性岩浆事件 源区性质 岩浆分异
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陕西三次强致灾性初夏区域性暴雨动力诊断对比分析
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作者 高菊霞 李文耀 +1 位作者 武麦凤 马晓华 《灾害学》 CSCD 北大核心 2024年第2期99-105,共7页
利用常规气象观测资料和0.25°×0.25°逐小时ERA5再分析资料,对综合评价强度指数300以上的三次陕西初夏区域性暴雨过程从水汽、动力垂直结构上进行对比分析。结果表明:①强致灾性初夏区域性暴雨发生前,中高层水汽输送来自... 利用常规气象观测资料和0.25°×0.25°逐小时ERA5再分析资料,对综合评价强度指数300以上的三次陕西初夏区域性暴雨过程从水汽、动力垂直结构上进行对比分析。结果表明:①强致灾性初夏区域性暴雨发生前,中高层水汽输送来自西南气流,低层来自偏东气流,低层水汽辐合发展加强,动力强迫主要表现为700 hPa以下正涡度区发展加强并向高层延伸,对应200 hPa附近出现强负涡度中心;②暴雨开始后,低层偏东水汽输送在暴雨过程中会发生变化,水汽辐合持续加强并向高层持续输送,散度场出现低层强辐合、高层辐散的结构,而关中有双重辐合-辐散特殊结构,且正涡度区继续向高层延伸、动力抬升促使上升运动延伸至400 hPa及以上;③初夏暴雨陕南动力强迫相比关中较弱,但水汽输送、水汽含量比关中好,降水效率更高、降水总量更大。 展开更多
关键词 初夏 区域性暴雨 水汽辐合 涡度 散度 垂直运动
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不同容量下并网模式交流微电网短路故障早期检测与区域定位 被引量:1
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作者 郑昕 甘鸿浩 《中国电机工程学报》 EI CSCD 北大核心 2024年第11期4353-4366,I0014,共15页
随着分布式电源(distributed generation,DG)的容量变化,微电网原有的供电结构发生改变,使得潮流大小、方向和功率结构发生变化,对快速检测和定位微电网中的短路故障区域提出了挑战。在MATLAB/Simulink中搭建低压交流微电网模型;通过高... 随着分布式电源(distributed generation,DG)的容量变化,微电网原有的供电结构发生改变,使得潮流大小、方向和功率结构发生变化,对快速检测和定位微电网中的短路故障区域提出了挑战。在MATLAB/Simulink中搭建低压交流微电网模型;通过高尺度小波能量谱算法对微电网与大电网公共连接点(point of common coupling,PCC)处检测到的电流进行分解,提取适应不同容量情况的短路故障特征值,实现了不同容量下微电网短路故障的早期检测;利用小波能量谱特征结合基于正交最小二乘法(orthogonal least square,OLS)的径向基函数(radial basis function,RBF)神经网络算法提出一种适用于不同容量微电网的短路故障区域定位方法,并进行仿真验证;在此基础上设计并网模式微电网短路故障保护硬件系统,并进行实验验证。结果表明,所设计的保护系统能够快速、准确地同时实现并网模式下交流微电网短路故障的早期检测与区域定位。 展开更多
关键词 并网模式微电网 短路故障 小波能量谱 正交最小二乘法(OLS) 径向基函数(RBF) 早期检测 区域定位
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档案文献所呈现的清前期在台湾地区设立土司之议
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作者 邹建达 张雷 《青海民族研究》 CSSCI 北大核心 2024年第2期178-186,共9页
康熙二十二年(1683年)至乾隆九年(1744年),清朝统一台湾地区后的六十余年间,闽台官员先后五次提出仿照施行于西南民族地区的土司制度,在台湾地区“番族社会”设立土司,其中康熙朝两次,雍正朝两次,乾隆朝一次。前三次均为“私议”,第四... 康熙二十二年(1683年)至乾隆九年(1744年),清朝统一台湾地区后的六十余年间,闽台官员先后五次提出仿照施行于西南民族地区的土司制度,在台湾地区“番族社会”设立土司,其中康熙朝两次,雍正朝两次,乾隆朝一次。前三次均为“私议”,第四次为南澳镇总兵许良彬的奏请,虽直达“天听”,但均未纳入清政府决策程序加以讨论。乾隆九年,福建布政使高山奏请在台湾地区“熟番”中设立土司,则经过户部议准、乾隆帝允行,再到闽浙总督马尔泰等提出反对并获乾隆帝支持的反复,前后历时近一年,最终被否决,相关讨论由此画上句号,此后再无人提及在台设立土司之事。本文拟通过档案文献厘清这一历史过程,并从雍正朝西南边疆实施大规模改土归流后土司制度的发展变化,结合同时期川西北“番族社会”设立“流职土司”情形,审视高山奏议所具有的积极意义和特殊历史价值。 展开更多
关键词 清前期 台湾地区“番族社会” 土司土官 流职土司 私议
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牡丹江地区早教社会服务体系的构建模式研究
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作者 顾媛媛 周世华 《牡丹江大学学报》 2024年第8期85-92,共8页
本文通过对牡丹江地区早教社会服务体系构建形式进行分析和研究,梳理出目前实践探索出的牡丹江地区早教社会服务三种体系构建模式,即中央财政支持的(普惠性托幼中心)、地方政府与高校合作的(社区普惠性托幼一体化幼儿园)、校企合作的(... 本文通过对牡丹江地区早教社会服务体系构建形式进行分析和研究,梳理出目前实践探索出的牡丹江地区早教社会服务三种体系构建模式,即中央财政支持的(普惠性托幼中心)、地方政府与高校合作的(社区普惠性托幼一体化幼儿园)、校企合作的(托幼一体化幼儿园)形式、优势、家长反馈效果。总结凝练出“丹江模式”早教社会服务体系,对我国托育和早教社会服务体系的构建有一定的借鉴性意义。 展开更多
关键词 牡丹江地区 早教 社会服务体系 构建模式 丹江模式
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秋季喀拉海海冰对2020和2021年12月京津冀冷暖反相的影响
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作者 车少静 高辉 +2 位作者 韩世茹 李晓帆 杜浩昱 《沙漠与绿洲气象》 2024年第2期132-137,共6页
京津冀2020年12月气温异常偏低,而2021年12月异常偏高。这两年冬季均处在拉尼娜背景下,但秋季喀拉海海冰异常有明显差异,可能是京津冀这两年12月气温异常潜在的外强迫信号。这2年秋季喀拉海海冰通过中高纬温度经向梯度差异引起大气环流... 京津冀2020年12月气温异常偏低,而2021年12月异常偏高。这两年冬季均处在拉尼娜背景下,但秋季喀拉海海冰异常有明显差异,可能是京津冀这两年12月气温异常潜在的外强迫信号。这2年秋季喀拉海海冰通过中高纬温度经向梯度差异引起大气环流异常,进而导致京津冀12月气温异常。2020年秋季喀拉海海冰异常偏少,导致12月西伯利亚高压偏强,乌拉尔山阻塞高压亦偏强,欧亚地区为典型的经向环流,造成京津冀12月气温异常偏低,而2021年的秋季海冰和12月环流形势均与2020年相反。 展开更多
关键词 京津冀 初冬气温 秋季海冰 喀拉海
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民族地区幼儿语言教育研究趋势与前沿可视化分析
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作者 冯海英 廖佳 郑晓宇 《兴义民族师范学院学报》 2024年第1期15-23,共9页
以中国知网(CNKI)数据库收录的所有民族地区幼儿语言教育相关文献为研究对象,运用CiteSpace软件对其进行可视化分析,研究结果显示:发文量呈上升趋势,在2013年、2018年、2021年达到了文献数量高峰期;从机构分布图看,形成了以西北师范大... 以中国知网(CNKI)数据库收录的所有民族地区幼儿语言教育相关文献为研究对象,运用CiteSpace软件对其进行可视化分析,研究结果显示:发文量呈上升趋势,在2013年、2018年、2021年达到了文献数量高峰期;从机构分布图看,形成了以西北师范大学、塔里木大学为代表的高产机构;研究热点主题为“双语教育”“国家通用语言”等;从关键词突现图看,双语教学为突现强度最高的关键词;研究经历了初步探索、发展停滞、跳跃式发展、深化探索四个阶段;结合研究结果,从政策体系、教学过程、评价标准、学术发展、家园社协同五个方面对未来研究提出了建议。 展开更多
关键词 幼儿语言教育 民族地区教育 可视化分析
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基于动态感兴趣区域和大数据的气象灾害动态预警方法
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作者 向立莉 《微型电脑应用》 2024年第5期192-195,共4页
为了降低气象灾害损失,提出基于动态感兴趣区域和大数据的气象灾害动态预警方法。构建客户端/服务器模式的气象灾害动态预警框架,采集气象相关信息及受灾主体信息,经数据处理层处理后,利用改进模糊C均值聚类算法,提取卫星云图的动态感... 为了降低气象灾害损失,提出基于动态感兴趣区域和大数据的气象灾害动态预警方法。构建客户端/服务器模式的气象灾害动态预警框架,采集气象相关信息及受灾主体信息,经数据处理层处理后,利用改进模糊C均值聚类算法,提取卫星云图的动态感兴趣区域,确定气象灾害场景及可能影响区域,采用3个改进深度收缩自编码网络,分别提取感兴趣区域气象因素、环境因素、受灾主体因素特征,构建场景识别的Softmax分类器,确定场景与各致灾因素的关联度,结合支持向量机确定气象灾害等级、类型,实现气象灾害的动态预警。实验结果表明,该方法聚类效果突出,能识别气象灾害类型及等级。 展开更多
关键词 动态感兴趣区域 大数据 气象灾害 动态预警 致灾因素
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血清金属蛋白酶组织抑制剂3和性别决定区Y框蛋白2在2型糖尿病肾损伤早期诊断中的临床应用
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作者 张洪利 王海成 +2 位作者 李华 未瑞超 曾玲 《临床肾脏病杂志》 2024年第7期529-535,共7页
目的探究血清金属蛋白酶组织抑制剂3(tissue inhibitors of metalloproteinases 3,TIMP3)和性别决定区Y框蛋白2(transcription factor determining region Y box protein 2,SOX2)对2型糖尿病(type 2 diabetes mellitus,T2DM)肾损伤的早... 目的探究血清金属蛋白酶组织抑制剂3(tissue inhibitors of metalloproteinases 3,TIMP3)和性别决定区Y框蛋白2(transcription factor determining region Y box protein 2,SOX2)对2型糖尿病(type 2 diabetes mellitus,T2DM)肾损伤的早期诊断。方法选取2022年4月至2023年4月在华北石油管理局总医院就诊的102例T2DM患者为研究对象,根据24 h尿蛋白排泄率(uri-nary albumin excretion rate,UAER)将T2DM患者分为肾损伤组(n=40)和无肾损伤组(n=62),另选取同期在华北石油管理局总医院行体检的健康者50名为对照组。酶联免疫吸附法测定所有受试者血清TIMP3、SOX2水平;比较3组受试者一般资料、糖化血红蛋白(hemoglobin A1c,HbA1c)、UAER、血肌酐(serum creatinine,Scr)、估算肾小球滤过率(estimated glomerular filtration rate,eGFR)、血清TIMP3、SOX2水平;Pearson相关性分析血清TIMP3与SOX2及两者与HbA1c、UAER、Scr、eGFR之间的关系;受试者工作特征曲线(receiver operating characteristic curve,ROC)分析血清TIMP3、SOX2对T2DM患者肾损伤的诊断价值。结果T2DM患者血清TIMP3[(0.68±0.17)μg/L比(1.35±0.35)μg/L]及eGFR[(105.99±20.56)mL·min^(-1)·(1.73 m^(2))比(133.15±26.18)mL·min^(-1)·(1.73 m^(2))^(-1)]显著低于对照组(P<0.05),且肾损伤患者血清TIMP3[(0.47±0.11)μg/L比(0.82±0.21)^(-1)μg/L]及eGFR[(74.69±10.22)mL·min^(-1)·(1.73 m^(2))比(126.18±27.23)mL·min^(-1)·(1.73 m^(2))^(-1)]显著低于无肾损伤患者(P<0.05);血清SOX2[(8.91±1.82)kU/L比(5.15±1.31)kU/L]及HbA1c[(8.80±1.55)%比(5.52±0.83)%]、UAER[(70.13±18.06)mg/24 h比(13.22±3.61)mg/24 h]、Scr[(82.14±15.23)µmol/L比(53.19±5.62)µmol/L]显著高于对照组(P<0.05),且肾损伤患者血清SOX2[(10.81±2.13)kU/L比(5.15±1.31)kU/L]及UAER[(156.83±40.29)mg/24 h比(13.22±3.61)mg/24 h]、Scr[(113.77±13.58)µmol/L比(53.19±5.62)µmol/L]显著高于无肾损伤患者(P<0.05)。Pearson相关性分析结果显示,TIMP3与UAER、Scr、HbA1c呈显著负相关(P<0.05),与eGFR呈显著正相关(P<0.05);SOX2与UAER、Scr、HbA1c呈显著正相关(P<0.05),与eGFR呈显著负相关(P<0.05);血清TIMP3与SOX2呈显著负相关(r=-0.590,P<0.05)。ROC结果显示,血清TIMP3联合SOX2诊断T2DM患者肾损伤的敏感度和特异度分别为95.0%、85.3%,显著高于TIMP3、SOX2单独测定。结论T2DM肾损伤患者血清TIMP3水平显著降低,SOX2水平显著升高,且两者与T2DM患者肾损伤密切相关,可用于T2DM患者肾损伤早期诊断。 展开更多
关键词 金属蛋白酶组织抑制剂3 性别决定区框蛋白2 2型糖尿病 肾损伤 早期诊断
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崇左市甘蔗主要品种应用现状分析与建议 被引量:1
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作者 赖振光 吴建明 +5 位作者 凌中华 王伦旺 张胜忠 刘晓婷 张华伟 邓宇驰 《甘蔗糖业》 2024年第2期22-32,共11页
为全面地了解崇左蔗区的甘蔗主要品种应用现状,为产业工作者制定相关政策、开展相关研究等提供参考,研究分析了崇左市甘蔗主产县(区)的近6个榨季甘蔗生产情况。研究结果表明,新品种、新技术的示范引导以及相关政策的实施,取得了较好的成... 为全面地了解崇左蔗区的甘蔗主要品种应用现状,为产业工作者制定相关政策、开展相关研究等提供参考,研究分析了崇左市甘蔗主产县(区)的近6个榨季甘蔗生产情况。研究结果表明,新品种、新技术的示范引导以及相关政策的实施,取得了较好的成效;崇左市蔗区种植面积保持稳定,桂糖42号等高产高糖良种的应用程度进一步提升,提高了蔗农和制糖企业的效益,但也存在品种结构多元化不足、脱毒种苗应用较少、机收水平低等问题。建议继续加强支持甘蔗产业稳定发展,加强区域性新品种的选育与推广、良种繁育基地建设、脱毒种苗的生产以及良种繁育技术的研发应用;开展针对性配套栽培技术的研发以重点提升蔗区主栽品种的生产表现,进一步发挥良种效应;加强适应不同地形地貌收割机械的研发、宜机收品种的选育与推广,多途径措施提升蔗区机收水平。 展开更多
关键词 甘蔗 崇左 区域性良种 早熟高糖 宿根性
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美国地震监测现状综述 被引量:1
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作者 吕帅 房立华 +1 位作者 任华育 周本伟 《地震工程学报》 CSCD 北大核心 2024年第2期431-448,共18页
美国的地震监测工作起步较早,在台网设计、设备研制、软件研发、标准制定、数据管理和新技术应用等领域处于领先地位。近年来,随着移动互联网的发展,以及强震动观测、地震预警和大规模流动台阵等项目的推进,美国的地震数据产品实现了从... 美国的地震监测工作起步较早,在台网设计、设备研制、软件研发、标准制定、数据管理和新技术应用等领域处于领先地位。近年来,随着移动互联网的发展,以及强震动观测、地震预警和大规模流动台阵等项目的推进,美国的地震数据产品实现了从单一向多元化、定制化的跨越。我国的地震监测工作虽起步较晚,但随着国家地震烈度速报与预警、“一带一路”地震监测台网和中国地震科学实验场等一系列重大项目的实施,地震站网密度、监测预警能力、地震数据智能处理、服务水平和新技术应用等方面都取得了跨越式发展。为更好地了解国际地震监测现状,文章从地震监测架构、地震台网布局、数据处理系统、地震预警系统和数据产品五个方面介绍了美国的地震监测工作进展,并与我国地震监测进行对比分析,可为我国地震监测预警事业规划和发展提供参考。 展开更多
关键词 美国地震监测 区域地震台网 地震预警 地震数据处理
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