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Summers骨凿提升上颌窦的临床应用 被引量:15
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作者 周磊 徐淑兰 +3 位作者 徐世同 黄建生 宋光保 张雪洋 《华西口腔医学杂志》 CAS CSCD 北大核心 2008年第3期296-298,共3页
目的评价Summers骨凿在上颌窦闭合式内提升、植骨及同期牙种植术中的效果。方法对上颌后牙区牙槽骨严重吸收的66例患者,采用Summers骨凿预备种植床,植入人工骨并同期植入种植体,术后6个月完成种植修复。结果66例患者上颌窦提升高度2-5 ... 目的评价Summers骨凿在上颌窦闭合式内提升、植骨及同期牙种植术中的效果。方法对上颌后牙区牙槽骨严重吸收的66例患者,采用Summers骨凿预备种植床,植入人工骨并同期植入种植体,术后6个月完成种植修复。结果66例患者上颌窦提升高度2-5 mm,术后皆无上颌窦炎发生。牙科CT扫描显示窦内形成一圆形光滑的突起,提升部位表面光滑完整,无黏膜穿破表现。6个月后X线片显示植入的骨材料无明显吸收,种植体骨结合完成。种植修复完成12-24个月后复查,无种植体松动、脱落,牙龈组织健康,种植体上部结构功能恢复满意。X线片显示:种植体与骨结合紧密,种植体周围骨垂直吸收小于1 mm。结论Summers骨凿可安全地提升上颌窦底,并可避免异位取骨,值得临床推广。 展开更多
关键词 summers骨凿 上颌窦提升 牙种植 骨移植
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使用Summers骨凿行上颌窦底提升不植骨的临床观察 被引量:5
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作者 常晓峰 贺龙龙 王晓霞 《实用口腔医学杂志》 CAS CSCD 北大核心 2011年第5期690-692,共3页
目的:观察分析不植骨的骨凿上颌窦底提升技术(osteotome sinus floor elevation,OSFE)应用在重度萎缩(余留牙槽嵴高度<6 mm)的上颌后牙区种植方案中的可能性。方法:对1名缺牙患者术前、术后即刻、术后6月锥体束CT资料进行分析,观察... 目的:观察分析不植骨的骨凿上颌窦底提升技术(osteotome sinus floor elevation,OSFE)应用在重度萎缩(余留牙槽嵴高度<6 mm)的上颌后牙区种植方案中的可能性。方法:对1名缺牙患者术前、术后即刻、术后6月锥体束CT资料进行分析,观察上颌窦底提升术后窦底的影像学变化。结果:通过OSFE技术植入2颗10 mm种植体,未作骨移植。6月后完成二期手术,随后完成固定义齿修复,随访观察2年,种植体正常行使功能。影像学检查显示上颌窦底发生改建,提升区域有新骨形成。结论:使用Summers骨凿技术可以在RBH高度小于6 mm的病例完成上颌窦底提升并同期植入种植体。 展开更多
关键词 上颌窦底提升术 OSFE summers骨凿 锥体束CT
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联合应用CAS-KIT工具盒和Summers骨凿的上颌窦内提升术的应用评价 被引量:3
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作者 王晓洁 郭莉 +2 位作者 梁泽梓 沈苏倩 陈宇梅 《中国口腔种植学杂志》 2015年第4期172-174,共3页
目的:研究联合应用CAS-KIT工具盒和Summers骨凿的上颌窦内提升术同期植入种植体的临床效果。方法:对20例30颗垂直骨量不足的上颌后牙联合应用CAS-KIT工具盒和Summers骨凿的上颌窦内提升术同期牙种植,种植体上部结构修复完成后6~36... 目的:研究联合应用CAS-KIT工具盒和Summers骨凿的上颌窦内提升术同期植入种植体的临床效果。方法:对20例30颗垂直骨量不足的上颌后牙联合应用CAS-KIT工具盒和Summers骨凿的上颌窦内提升术同期牙种植,种植体上部结构修复完成后6~36个月定期复查。结果:观察期内,30枚种植体与周围组织均形成良好的骨性结合,能行使较好的咀嚼功能。结论: CAS-KIT工具盒和Summers骨凿的联合应用充分发挥了各自的优点,扩大了上颌窦内提升术的适应症;避开了CAS-KIT工具盒液压升降装置的使用不便和Summers骨凿在敲击中产生的不适感,是一种更为安全可靠的方法。 展开更多
关键词 上颌窦内提升术 种植义齿 CAS-KIT工具盒 summers骨凿
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IBS内提骨凿与Summers骨凿行上颌窦内提升效果比较的实验研究 被引量:2
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作者 温红霞 范亚伟 《中国口腔种植学杂志》 2018年第3期114-118,135,共6页
目的:建立上颌窦内提升的山羊动物实验模型,比较IBS内提骨凿与Summers骨凿进行山羊上颌窦内提升的效果。方法:大量预实验对山羊上颌窦解剖分析,结合山羊CBCT对上颌窦提升位点探讨,建立上颌窦内提升的山羊动物实验模型。对18只本地山羊3... 目的:建立上颌窦内提升的山羊动物实验模型,比较IBS内提骨凿与Summers骨凿进行山羊上颌窦内提升的效果。方法:大量预实验对山羊上颌窦解剖分析,结合山羊CBCT对上颌窦提升位点探讨,建立上颌窦内提升的山羊动物实验模型。对18只本地山羊36个上颌窦左右随机分为实验组与对照组,实验组运用IBS内提骨凿,对照组运用Summers骨凿,18只山羊依据上颌窦提升高度为5,8,10mm随机分为3组,每组6只羊头,统计每组实验组与对照组的穿孔数并记录穿孔时上颌窦提升的高度。结果:建立了以山羊上颌第一磨牙腭侧6-8mm的位点进行上颌窦内提升的动物实验模型。每组实验组6个上颌窦穿孔数分别为0、1、3;对照组6个上颌窦穿孔数分别为1、5、6。实验组与对照组行上颌窦内提升高度为5mm时两者安全性无明显差异[(5.00±0.00) mm vs(4.92±0.20) mm,P>0.05],实验组与对照组行上颌窦内提升高度为8mm时两者差异显著[(7.83±0.41) mm vs (6.58±1.32) mm,P<0.05],实验组与对照组行上颌窦内提升高度为10mm时两者安全性差异显著[(9.17±1.57) mm vs (6.08±0.97) mm,P<0.05]。结论:山羊上颌第一磨牙腭侧6-8mm的位点进行上颌窦内提升效果显著,当提升高度小于5mm,两者提升效果无明显差异,提升高度大于5mm,两骨凿相较而言,IBS内提骨凿较Summers骨凿有更好的提升效果及安全性。 展开更多
关键词 IBS内提骨凿 summers骨凿 上颌窦提升高度 山羊动物实验模型
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Summers Kill综合征1例
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作者 刘湘君 赵汝君 王立山 《中国社区医师》 2006年第11期30-30,共1页
关键词 summers Kill综合征 皮肤瘙痒 巩膜黄染 胃内容物 入院前 20岁
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Northward Heat Flux in Midwest Summers
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作者 Kern E. Kenyon 《International Journal of Geosciences》 2013年第8期1117-1119,共3页
Watching the winds in northwest Iowa during more than 30 summers has led me to two conclusions about the local atmosphere at ground level: there is a net northward transport of heat and water taking place throughout t... Watching the winds in northwest Iowa during more than 30 summers has led me to two conclusions about the local atmosphere at ground level: there is a net northward transport of heat and water taking place throughout the summer;warm humid winds from the south continually alternate with cool dry winds from the north. The proposed northward heat transfer is consistent with the constraint, placed on the motions of the oceans and the atmosphere, of the earth’s heat balance due to the increased absorption of solar radiation at low latitudes compared to that at high latitudes. At mid-latitudes in the interior of continents, like North America, it is the job of the atmosphere alone to constantly help satisfy the global heat balance. Although qualitative in nature, the predicted northward heat flux is strongly based on frequent observations over lengthy time intervals. 展开更多
关键词 NORTHWARD HEAT FLUX MIDWEST summers
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Impacts of Polar Vortex,NPO,and SST Configurations on Unusually Cool Summers in Northeast China.Part I:Analysis and Diagnosis 被引量:7
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作者 廉毅 沈柏竹 +5 位作者 李尚锋 赵滨 高枞亭 刘刚 刘平 曹玲 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第1期193-209,共17页
This study unveils the evolution of two major early signals in the North Pacific atmosphere-ocean system that heralded abnormal high-pressure blockings and cold-vortex activities across Northeast China, based on an an... This study unveils the evolution of two major early signals in the North Pacific atmosphere-ocean system that heralded abnormal high-pressure blockings and cold-vortex activities across Northeast China, based on an analysis of the configurations of major modes including the polar vortex, the North Pacific Oscillation (NPO), and SST in the preceding winter and spring and atmospheric low-frequency disturbances in Northeast China. We analyzed these aspects to understand the atmosphere ocean physical coupling processes characterized by the two early signals, and here we explain the possible mechanisms through which dipole circulation anomalies affect the summer low-temperature processes in Northeast China. We further analyzed the interdecadal variation background and associated physical processes of the two early signals. 展开更多
关键词 polar vortex NPO North Pacific SST atmosphere-ocean coupling summer low temperatures in Northeast China dipole pattern
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Numerical Experiments on the Impact of Spring North Pacific SSTA on NPO and Unusually Cool Summers in Northeast China 被引量:5
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作者 LIAN Yi ZHAO Bin +2 位作者 SHEN Baizhu LI Shangfeng LIU Gang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第6期1305-1315,共11页
A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold (warm) El Ni(n)o (La Ni(n)a) phases in the Ni(n)o4 region and sea surface temperature a... A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold (warm) El Ni(n)o (La Ni(n)a) phases in the Ni(n)o4 region and sea surface temperature anomalies (SSTA) in the westerly drifts region would result in abnormally enhanced NorthEast Cold Vortex (NECV) activities in early summer.In spring,the central equatorial Pacific El Ni(n)o phase and westerly drift SSTA forcing would lead to the retreat of non-adiabatic waves,inducing elliptic low-frequency anomalies of tropical air flows.This would enhance the anomalous cyclone-anticyclonecyclone-anticyclone low-frequency wave train that propagates from the tropics to the extratropics and further to the mid-high latitudes,constituting a major physical mechanism that contributes to the early summer circulation anomalies in the subtropics and in the North Pacific mid-high latitudes.The central equatorial Pacific La Ni(n)a forcing in the spring would,on the one hand,induce teleconnection anomalies of high pressure from the Sea of Okhotsk to the Sea of Japan in early summer,and on the other hand indirectly trigger a positive low-frequency East Asia-Pacific teleconnection (EAP) wave train in the lower troposphere. 展开更多
关键词 atmospheric model westerly drifts Ni(n)o4 SSTA low-frequency variation circulation pattern cool summer Northeast China
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Simulation of the western North Pacific subtropical high in El Ni?o decaying summers by CMIP5 AGCMs 被引量:1
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作者 DONG Xiao FAN Fang-Xing +2 位作者 LIN Ren-Ping JIN Jiang-Bo LIAN Ru-Xu 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第2期146-155,共10页
The performances of CMIP5 atmospheric general circulation models (AGCMs) in simulating the western North Pacific subtropical high (WNPSH) in El Nino decaying summers are examined in this study. Results show that m... The performances of CMIP5 atmospheric general circulation models (AGCMs) in simulating the western North Pacific subtropical high (WNPSH) in El Nino decaying summers are examined in this study. Results show that most models can reproduce the spatial pattern of both climatological and anomalous circulation associated with the WNPSH in El Nino decaying summers. Most CMIP5 AGCMs can capture the westward shift of the WNPSH in El Nino decaying summers compared with the climatological location. With respect to the sub-seasonal variation of the WNPSH, the performances of these AGCMs in reproducing the northward jump of the WNPSH are better than simulating the eastward retreat of the WNPSH from July to August. Twenty-one out of twenty-two (20 out of 22) models can reasonably reproduce the northward jump of the WNPSH in El Nino decaying summers (climatology), while only 7 out of 22 (8 out of 22) AGCMs can reasonably reproduce the eastward retreat of the WNPSH in El Nino decaying summers (climatology). In addition, there is a close connection between the climatological WNPSH location bias and that in El Nino decaying summers. 展开更多
关键词 Western North Pacific subtropical high El Nino decaying summer CMIPS AGCM sub-seasonal variation
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Characteristics of Atmospheric Rivers over the East Asia in Middle Summers from 2001 to 2016 被引量:1
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作者 FU Gang LIU Shan +2 位作者 LI Xiaodong LI Pengyuan CHEN Lijia 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期235-243,共9页
Atmospheric Rivers(ARs) are narrow and elongated water vapor belts in troposphere with meridional transport across the mid-latitudes towards high-latitudes. Compared with ARs occurred over the northeastern Pacific, th... Atmospheric Rivers(ARs) are narrow and elongated water vapor belts in troposphere with meridional transport across the mid-latitudes towards high-latitudes. Compared with ARs occurred over the northeastern Pacific, the western coast of North America and Europe, the ARs over the East Asia have received less attention. In this paper, the characteristics of ARs which affected China in the area 20?–60?N, 95?–165?E in the middle summer season from 2001 to 2016 were investigated by using European Center for Medium-Range Weather Forecasts(ECMWF) ERA-Interim reanalysis data and Multi-functional Transport Satellites-1 R(MTSAT-1 R) infrared data. Totally, 134 ARs occurred during that period, and averagely 8.4 ARs occurred per year. Statistically, 101 ARs were in east-west orientation, and 33 ARs were in north-south orientation, which accounts for about 75% and 25%, respectively. Herein we report the occurrence number, duration time, intensity, length, width, ratio of length to width, and extension orientation of these ARs, which provide the basic information for those who have interest in ARs over the East Asia. 展开更多
关键词 narrow and elongated water vapor belt East Asia middle summer season Meiyu/Baiu front characteristics of atmospheric rivers infrared satellite data
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Climatic implications in earlywood and latewood width indices of Chinese pine in north central China
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作者 Kaixuan Yang Junzhou Zhang +1 位作者 Haowen Fan Yuan Yan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期143-153,共11页
Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern Hemisphere.However,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often... Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern Hemisphere.However,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW index.In this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains,north central China.The climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation signals.Correlation analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate signals.However,after removing the effect of earlywood growth using a simple regression model,the adjusted LWW chronology(LWW_(adj))showed a strong relationship with July precipitation in dry years.This suggests that the LWW_(adj) chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions. 展开更多
关键词 DENDROCLIMATOLOGY Latewood width Climate response Summer precipitation Earlywood effect
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Differences in Precipitation and Related Wind Dynamics and Moisture and Heat Features in Separate Areas of the South China Sea before and after Summer Monsoon Onset
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作者 Chunyan ZHANG Donghai WANG +3 位作者 Kaifeng ZHANG Wanwen HE Yanping ZHENG Yan XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1643-1660,共18页
Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different area... Using surface and balloon-sounding measurements, satellite retrievals, and ERA5 reanalysis during 2011–20, this study compares the precipitation and related wind dynamics, moisture and heat features in different areas of the South China Sea(SCS) before and after SCS summer monsoon onset(SCSSMO). The rainy sea around Dongsha(hereafter simply referred to as Dongsha) near the north coast, and the rainless sea around Xisha(hereafter simply referred to as Xisha) in the western SCS, are selected as two typical research subregions. It is found that Dongsha, rather than Xisha, has an earlier and greater increase in precipitation after SCSSMO under the combined effect of strong low-level southwesterly winds, coastal terrain blocking and lifting, and northern cold air. When the 950-h Pa southwesterly winds enhance and advance northward, accompanied by strengthened moisture flux, there is a strong convergence of wind and moisture in Dongsha due to a sudden deceleration and rear-end collision of wind by coastal terrain blocking. Moist and warm advection over Dongsha enhances early and deepens up to 200 h Pa in association with the strengthened upward motion after SCSSMO, thereby providing ample moisture and heat to form strong precipitation. However, when the 950-h Pa southwesterly winds weaken and retreat southward, Xisha is located in a wind-break area where strong convergence and upward motion centers move in. The vertical moistening and heating by advection in Xisha enhance later and appear far weaker compared to that in Dongsha, consistent with later and weaker precipitation. 展开更多
关键词 Dongsha Xisha South China Sea summer monsoon onset PRECIPITATION wind dynamics MOISTURE HEAT
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Betaine addition to the diet alleviates intestinal injury in growing rabbits during the summer heat through the AAT/mTOR pathway
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作者 Zimei Li Junning Pu +6 位作者 Xiang Chen Yanbin Chen Xiaoyan Peng Jingyi Cai Gang Jia Hua Zhao Gang Tian 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1623-1637,共15页
Background The aim of this experiment was to investigate the effect of different levels of betaine(Bet)inclusion in the diet on the intestinal health of growing rabbits under summer heat.A total of 100 weaned Qixing m... Background The aim of this experiment was to investigate the effect of different levels of betaine(Bet)inclusion in the diet on the intestinal health of growing rabbits under summer heat.A total of 100 weaned Qixing meat rabbits aged 35 d with body weight of 748.61±38.59 g were randomly divided into 5 treatment groups:control group(basal diet)and Bet groups(basal diet+0.75,1.0,1.5 or 2.0 g/kg Bet).The average daily temperature in the rabbitry during the experiment was 30.48°C and the relative humidity was 69.44%.Results Dietary addition of Bet had no significant effect on growth performance and health status of growing rabbits(P>0.05),but it increased ileal secretory immunoglobulin A content compared to the control under summer heat(P<0.05).Addition of 0.75 g/kg Bet up-regulated jejunal IL-4,down-regulated ileal TNF-αexpression(P<0.05).The addition of 1.0 g/kg Bet increased the villi height(VH)in the jejunum(P<0.05).Serum glucose levels were reduced,and the expression of SLC6A20 was up-regulated in jejunum and ileum of rabbits fed with 1.5 g/kg Bet(P<0.05).When added at 2.0 g/kg,Bet reduced serum HSP70 content,increased jejunal VH,and up-regulated duodenal SLC7A6,SLC38A2,mTOR and 4EBP-2 expression(P<0.05).Correlation analysis revealed that intestinal mTOR expression was significantly and positively correlated with SLC7A6,SLC38A2,SLC36A1 and IL-4 expression(P<0.05).Conclusions Dietary addition of Bet can up-regulate the expression of anti-inflammatory factors through the AAT/mTOR pathway,improve the intestinal immune function,alleviate intestinal damage in growing rabbits caused by summer heat,and improve intestinal health. 展开更多
关键词 AAT/mTOR BETAINE Growing rabbits Intestinal injury Summer heat
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Time-lagged Effects of the Spring Atmospheric Heat Source over the Tibetan Plateau on Summer Precipitation in Northeast China during 1961–2020:Role of Soil Moisture
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作者 Yizhe HAN Dabang JIANG +2 位作者 Dong SI Yaoming MA Weiqiang MA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1527-1538,共12页
The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in N... The spring atmospheric heat source(AHS)over the Tibetan Plateau(TP)has been suggested to affect the Asian summer monsoon and summer precipitation over South China.However,its influence on the summer precipitation in Northeast China(NEC)remains unknown.The connection between spring TP AHS and subsequent summer precipitation over NEC from 1961 to 2020 is analyzed in this study.Results illustrate that stronger spring TP AHS can enhance subsequent summer NEC precipitation,and higher soil moisture in the Yellow River Valley-North China region(YRVNC)acts as a bridge.During spring,the strong TP AHS could strengthen the transportation of water vapor to East China and lead to excessive rainfall in the YRVNC.Thus,soil moisture increases,which regulates local thermal conditions by decreasing local surface skin temperature and sensible heat.Owing to the memory of soil moisture,the lower spring sensible heat over the YRVNC can last until mid-summer,decrease the land–sea thermal contrast,and weaken the southerly winds over the East Asia–western Pacific region and convective activities over the South China Sea and tropical western Pacific.This modulates the East Asia–Pacific teleconnection pattern,which leads to a cyclonic anomaly and excessive summer precipitation over NEC. 展开更多
关键词 Tibetan Plateau atmospheric heat source Northeast China summer precipitation soil moisture
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A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area
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作者 H.N.Sowmya M.Dinamani +4 位作者 G.P.Shivashankara H.K.Ramaraju B.S.Surendra Vijaya V.Shanbhag R.Prajwal 《Research in Cold and Arid Regions》 CSCD 2024年第1期14-19,共6页
In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was c... In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. Hourly sample data was collected using a BTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 a.m.to 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. However, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions. 展开更多
关键词 BTEX Summer variation Meteorological parameters Correlation
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Characteristics and triggering mechanisms of early negative Indian Ocean Dipole
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作者 Yue Fang Shuangwen Sun +2 位作者 Yongcan Zu Jianhu Wang Lin Feng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期59-65,共7页
Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in... Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts. 展开更多
关键词 Indian Ocean Dipole(IOD) triggering mechanism Indian summer monsoon seasonal cycle negative IOD
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Effects of Slow-release Nitrogen Fertilizer on Yield and Nitrogen Accumulation of Summer Maize in Shajiang Black Soil Area
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作者 Yongfeng XING Changmin WEI +7 位作者 Guoli CHEN Weimeng XU Wanyou SONG Guizhi LI Wenwei ZHOU Yanwei WAN Enzhong ZHOU Weifang LI 《Agricultural Biotechnology》 2024年第2期72-74,共3页
[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the ap... [Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area. 展开更多
关键词 Slow-release nitrogen fertilizer Shajiang black soil Summer maize Nitrogen metabolism YIELD
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Effects of Slow-release Nitrogen on Dry Matter Accumulation,Translocation and Yield of Summer Maize
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作者 Yongfeng XING Guoli CHEN +6 位作者 Changmin WEI Weimeng XU Wanyou SONG Guizhi LI Yanwei WAN Enzhong ZHOU Weifang LI 《Agricultural Biotechnology》 2024年第3期11-13,共3页
[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six differen... [Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six different treatment were set up:blank control(CK1),slow-release urea 75 kg/hm^(2)(C1),slow-release urea 150 kg/hm^(2)(C2),slow-release urea 225 kg/hm^(2)(C3),slow-release urea 300 kg/hm^(2)(C4)and ordinary urea 300 kg/hm^(2)(CK2),to study the change law of dry matter accumulation and translocation in summer maize.[Results]Treatment slow-release urea 225 kg/hm^(2)(C4)showed summer maize yield,dry matter translocation between organs,grain contribution rate and proportion of grain dry matter in the full ripe stage higher than other treatments.Considering the weight loss and cost factors,slow-release urea 225 kg/hm^(2)(C3)could be recommended as the fertilizing amount for summer maize.[Conclusions]This study provides theoretical reference for rational selection of fertilizers for reducing fertilizer application and increasing fertilizer efficiency,and for production of summer maize in Shajiang black soil region. 展开更多
关键词 Slow-release nitrogen fertilizer Summer maize Dry matter accumulation TRANSLOCATION
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Analysis of Changing Trend of Summer Precipitation in North China
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作者 Wei LIU 《Meteorological and Environmental Research》 2024年第4期15-20,23,共7页
Based on the reanalysis data of the National Center for Environmental Prediction(NCEP)and the precipitation dataset of the U.S.Climate Prediction Center(CPC),the changing trend of summer precipitation in North China(3... Based on the reanalysis data of the National Center for Environmental Prediction(NCEP)and the precipitation dataset of the U.S.Climate Prediction Center(CPC),the changing trend of summer precipitation in North China(35°-40°N,110°-125°E)during 1979-2020 was studied.By calculating the monthly climatic precipitation in North China,it is found that precipitation was mainly distributed from June to August,so the trend of precipitation in North China from June to August was mainly analyzed.Firstly,the five-point moving average of regional mean precipitation in North China from June to August during 1979-2020 was conducted.It is found that the fitting curve of the five-point sliding average was basically consistent with the changing trend of regional precipitation,and it showed a certain upward trend.Secondly,the cumulative anomaly of regional average summer precipitation in North China showed a significant upward trend after 2005,which was similar to the moving average result,indicating that the precipitation in the later period increased compared with the earlier period.The changing trend of summer precipitation in North China in the past 42 years was analyzed,and the results show that precipitation showed a significant increasing trend in most areas of North China,so that regional average precipitation also tended to increase significantly.By comparing the precipitation in the past five years(2016-2020)and the last 36 years(1979-2015),it is found that the increase of summer precipitation in North China was more obvious,so the reasons for the increase in precipitation were further analyzed.Since the occurrence of precipitation requires favorable thermal dynamic conditions,the one-dimensional linear regression of water vapor content at 850 hPa and meridional wind speed was conduced,and it is found that the two variables tended to increase obviously,which was consistent with the increasing trend of precipitation.Seen from both the results of regional average and the spatial distribution of trends,the lower atmospheric water vapor content and wind speed showed a significant positive trend,which led to the increase of summer precipitation.Therefore,it can be concluded that there was a certain changing trend of summer precipitation in North China in the past 42 years,which can provide certain reference for the future forecast of summer precipitation in North China. 展开更多
关键词 North China Summer precipitation Trend analysis
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Multi-decadal Changes of the Impact of El Niño Events on Tibetan Plateau Summer Precipitation
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作者 Weinan Jiang Ning Cao +1 位作者 Riga Aze Jianjun Xu 《Journal of Atmospheric Science Research》 2024年第1期90-105,共16页
Precipitation on the Tibetan Plateau(TP)has an important effect on the water supply and demand of the downstream population.Involving recent climate change,the multi-decadal variations of the impact of El Niño-So... Precipitation on the Tibetan Plateau(TP)has an important effect on the water supply and demand of the downstream population.Involving recent climate change,the multi-decadal variations of the impact of El Niño-Southern Oscillation(ENSO)events on regional climate were observed.In this work,the authors investigated the changes in summer precipitation over TP during 1950-2019.At the multi-decadal scale,the authors found that the inhabiting impact of El Niño events on the TP summer precipitation has strengthened since the late 1970s.The main factor contributing to this phenomenon is the significant amplification in the decadal amplitude of El Niño during 1978-2019 accompanied by a discernible escalation in the frequency of El Niño events.This phenomenon induces anomalous perturbations in sea surface temperatures(SST)within the tropical Indo-Pacific region,consequently weakening the atmospheric vapor transport from the western Pacific to the TP.Additionally,conspicuous anomalies in subsidence motion are observed longitudinally and latitudinally across the TP which significantly contributes to a curtailed supply of atmospheric moisture.These results bear profound implications for the multi-decadal prediction of the TP climate. 展开更多
关键词 Tibetan plateau Summer precipitation ENSO Multi-decadal changes Climate variability
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