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Surface phonon resonance:A new mechanism for enhancing photonic spin Hall effect and refractive index sensor
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作者 程杰 汪承龙 +3 位作者 李一铭 张亚林 刘胜利 董鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期254-261,共8页
Metal-based surface plasmon resonance(SPR)plays an important role in enhancing the photonic spin Hall effect(SHE)and developing sensitive optical sensors.However,the very large negative permittivities of metals limit ... Metal-based surface plasmon resonance(SPR)plays an important role in enhancing the photonic spin Hall effect(SHE)and developing sensitive optical sensors.However,the very large negative permittivities of metals limit their applications beyond the near-infrared regime.In this work,we theoretically present a new mechanism to enhance the photonic SHE by taking advantage of SiC-supported surface phonon resonance(SPhR)in the mid-infrared regime.The transverse displacement of photonic SHE is very sensitive to the wavelength of incident light and the thickness of SiC layer.Under the optimal parameter setup,the calculated largest transverse displacement of SiC-based SPhR structure reaches up to 163.8 ym,which is much larger than the condition of SPR.Moreover,an NO_(2) gas sensor based on the SPhR-enhanced photonic SHE is theoretically proposed with the superior sensing performance.Both the intensity and angle sensitivity of this sensor can be effectively manipulated by varying the damping rate of SiC.The results may provide a promising paradigm to enhance the photonic SHE in the mid-infrared region and open up new opportunity of highly sensitive refractive index sensors. 展开更多
关键词 photonic spin Hall effect refractive index sensor surface phonon resonance SIC
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Relationship between neonatal respiratory distress syndrome pulmonary ultrasonography and respiratory distress score,oxygenation index,and chest radiography grading
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作者 Hai Yang Li-Jun Gao +5 位作者 Jing Lei Qiang Li Liu Cui Xiao-Hua Li Wu-Xuan Yin Sen-Hua Tian 《World Journal of Clinical Cases》 SCIE 2024年第20期4154-4165,共12页
BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a ... BACKGROUND Accurate condition assessment is critical for improving the prognosis of neonatal respiratory distress syndrome(RDS),but current assessment methods for RDS pose a cumulative risk of harm to neonates.Thus,a less harmful method for assessing the health of neonates with RDS is needed.AIM To analyze the relationships between pulmonary ultrasonography and respiratory distress scores,oxygenation index,and chest X-ray grade of neonatal RDS to identify predictors of neonatal RDS severity.METHODS This retrospective study analyzed the medical information of 73 neonates with RDS admitted to the neonatal intensive care unit of Liupanshui Maternal and Child Care Service Center between April and December 2022.The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest Xray grade of each newborn before and after treatment were collected.Spearman correlation analysis was performed to determine the relationships among these values and neonatal RDS severity.RESULTS The pulmonary ultrasonography score,respiratory distress score,oxygenation index,and chest X-ray RDS grade of the neonates were significantly lower after treatment than before treatment(P<0.05).Spearman correlation analysis showed that before and after treatment,the pulmonary ultrasonography score of neonates with RDS was positively correlated with the respiratory distress score,oxygenation index,and chest X-ray grade(ρ=0.429–0.859,P<0.05).Receiver operating characteristic curve analysis indicated that pulmonary ultrasonography screening effectively predicted the severity of neonatal RDS(area under the curve=0.805–1.000,P<0.05).CONCLUSION The pulmonary ultrasonography score was significantly associated with the neonatal RDS score,oxygenation index,and chest X-ray grade.The pulmonary ultrasonography score was an effective predictor of neonatal RDS severity. 展开更多
关键词 Neonatal respiratory distress syndrome Pulmonary ultrasonography Ultrasonography score Respiratory distress score Oxygenation index Chest X-ray grading
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基于SPI和VHI的长江中下游地区干旱时空特征分析
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作者 向大享 姜莹 +1 位作者 陈喆 李喆 《长江科学院院报》 CSCD 北大核心 2024年第3期153-159,165,共8页
近60 a来,长江中下游地区干旱发生频率越来越高,强度不断增强,影响范围不断扩大,持续时间不断变长,对经济发展造成了严重的影响。通过构建长江中下游地区60 a长序列历史降水数据和40 a遥感数据集,基于标准化降水指数、植被健康指数等指... 近60 a来,长江中下游地区干旱发生频率越来越高,强度不断增强,影响范围不断扩大,持续时间不断变长,对经济发展造成了严重的影响。通过构建长江中下游地区60 a长序列历史降水数据和40 a遥感数据集,基于标准化降水指数、植被健康指数等指标建立干旱监测指数序列库,分析时序干旱指数变化特征,开展旱情时空分布、季节差异、发生频次等指标统计分析,探究旱情发生频率及其时空分异特征、旱情程度等时空特征。研究结果表明:长江中下游地区干旱事件发生具有明显的季节性,春夏季干旱频率高,秋冬季干旱频率低;干旱存在明显区域性差异,易旱地区主要包括湖北北部、湖南南部等地。 展开更多
关键词 干旱 时空特征 spi VHI 长江中下游地区
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基于SPI-RRV指数中国气象干旱及其风险时空演变特征研究 被引量:1
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作者 杨肖丽 罗定 +4 位作者 叶周兵 谢灵枫 任立良 江善虎 袁山水 《水资源保护》 EI CSCD 北大核心 2024年第1期44-51,共8页
为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定... 为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定和时空可比性强的特点,能够较为准确地评估气象干旱风险时空演变特征;南方平均干旱栅格比、干旱月占比和频次大于北方,湿润区和半湿润区干旱历时短、烈度大,半干旱区和干旱区干旱历时长、烈度相对较小;干旱高风险区转移具有显著年代际变化规律,空间上从西北向西南地区转移。 展开更多
关键词 气象干旱 标准化降水指数 可靠性-回弹性-脆弱性指数 干旱风险
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PTI、IoC2和SPI在全身麻醉患者镇痛深度监测中的价值
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作者 张莹 沈朱杭 +3 位作者 沈权伟 吴美华 史思仁 赵文胜 《浙江临床医学》 2024年第7期1051-1053,共3页
目的探讨镇痛指数(PTI)、伤害敏感指数(IoC2)和手术容积指数(SPI)在全身麻醉患者镇痛深度监测中的价值。方法选取择期行腹腔镜胆囊切除术患者90例,采用区组随机法,按照不同镇痛深度监测指标分为IoC2组(A组)、SPI组(B组)和PTI组(C组),每... 目的探讨镇痛指数(PTI)、伤害敏感指数(IoC2)和手术容积指数(SPI)在全身麻醉患者镇痛深度监测中的价值。方法选取择期行腹腔镜胆囊切除术患者90例,采用区组随机法,按照不同镇痛深度监测指标分为IoC2组(A组)、SPI组(B组)和PTI组(C组),每组各30例。记录并比较各时间点患者心率(HR)、平均动脉压(MAP)、IoC2、SPI、PTI,测定并比较术前、术中和术后血清炎症因子(IL-6、IL-10)的水平。结果T2时IoC2、SPI和PTI与T1时比较(P<0.001);T3时SPI和PTI与T2时比较(P<0.05);T4时PTI和SPI与T3时比较(P<0.05);T4时IoC2与T2、T3时比较(P<0.001);T6时SPI和PTI与T5时比较(P<0.05);T7时IoC2、SPI、PTI与T5时比较(P<0.05);T8时IoC2、SPI和PTI与T7时比较(P<0.05)。各组内比较,IoC2、SPI和PTI具有时间变化趋势,且随着时间点不同均发生变化(P<0.001)。三组组间比较,HR、MAP、IoC2、SPI和PTI时间与组间存在交互效应,具有不相等的变化趋势(P<0.001)。IoC2、SPI、PTI与HR和MAP均呈正相关(P<0.05)。三组患者IL-6和IL-10术前、术中和术后比较,差异无统计学意义(P>0.05)。结论IoC2、PTI和SPI可作为全身麻醉术中疼痛监测的可靠指标,减轻术中应激反应,准确性优于HR、MAP。 展开更多
关键词 镇痛深度 伤害敏感指数 手术容积指数 镇痛指数 全身麻醉
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基于标准化降水指数(SPI)的宁夏中部干旱带旱灾危险性时空演变特征
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作者 丛士翔 王融融 +2 位作者 常文静 余海龙 黄菊莹 《水土保持研究》 CSCD 北大核心 2024年第4期223-232,共10页
[目的]揭示宁夏中部干旱带旱灾危险性的时空特征,为宁夏中部干旱带农业生产、农业灾害防治、种植结构调整和农业灌溉指导提供科学依据。[方法]收集宁夏中部干旱带的沙坡头区、中宁县、同心县、盐池县、海原县5个气象站点的气象观测资料... [目的]揭示宁夏中部干旱带旱灾危险性的时空特征,为宁夏中部干旱带农业生产、农业灾害防治、种植结构调整和农业灌溉指导提供科学依据。[方法]收集宁夏中部干旱带的沙坡头区、中宁县、同心县、盐池县、海原县5个气象站点的气象观测资料,采用标准化降水指数(SPI)分析了近39年(1981—2019年)干旱等级的时空变化,并结合GIS技术评价其旱灾危险性时空演变特征。[结果]SPI 12结果表明代际干旱趋势呈波动中加剧趋势(趋势线斜率范围为-0.004~0.003)。SPI 3结果表明季尺度旱灾危险性时空分布异质性明显,空间上呈现出南低北高的特征,而时间上则表现为连旱特征突出。春冬两季旱灾发生频率高于45%;夏、秋两季干旱现象不显著,干旱发生频率处于10.26%~43.59%之间;旱灾危险性时空演变特征评价结果表明代际旱灾危险性呈现先下降后上升的变化趋势。季尺度旱灾危险性时空差异明显,空间上表现为旱灾危险性由南向北升高,时间上表现为春冬两季旱灾危险性较高,而夏、秋两季旱灾危险性较低。[结论]宁夏中部干旱带季尺度旱灾危险性时空异质性明显,沙坡头区、中宁县旱灾危险性高,未来应加强春、秋、冬三季的旱灾防治。 展开更多
关键词 旱灾 标准化降水指数(spi) 宁夏中部干旱带 时空演变特征
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科学与政策接口(SPI)的基本特征和研究实践
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作者 魏伟珍 张冬荣 《智库理论与实践》 北大核心 2024年第3期29-39,共11页
[目的/意义]科学研究应充分参与和有效支撑政策制定已成为共识,但从认知到实践,却仍然存在知识结构、沟通渠道、流程规范等阻碍因素,科学与政策接口(science-policy interfaces,SPI)为构建结构良好的科学和政策互动关系提供了新的研究... [目的/意义]科学研究应充分参与和有效支撑政策制定已成为共识,但从认知到实践,却仍然存在知识结构、沟通渠道、流程规范等阻碍因素,科学与政策接口(science-policy interfaces,SPI)为构建结构良好的科学和政策互动关系提供了新的研究视角。[方法/过程]通过文献调研探究SPI的基本特征和发展现状,梳理理论发展脉络和概念内涵,基于SPI核心要素和关系模式分析对其运作方式进行阐释,以影响广泛的2项实践案例剖析SPI的具体实现效果和价值。[结果/结论]SPI的基本特征表现为对多种参与主体和复杂互动关系的关注,通过边界组织的信息收集和知识转化功能来弥合科研人员与政府决策者之间知识储备及需求表达的差距,将研究层次由问题描述导向至基于案例的方案预设和规则建立,与当前循证决策研究的方法和目标充分契合,从而超越了当前对科学与政策间单向互动的“线性模式”的反思研究,推动实践转变为双向可持续互动的“交互模式”或“共同生产模式”。SPI可为科学研究参与支撑政策制定的实践探索提出新的建议和发展方向,包括知识基础设施建设、工具和技能提升、文化和本土要素纳入、投资和主题指导、科学外交和多层合作等多个方面。 展开更多
关键词 科学与政策接口 spi 共同生产 边界组织 循证决策
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Spatio-Temporal Analysis of Drought in the North-Eastern Coastal Region of Vietnam Using the Standardized Precipitation Index (SPI)
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作者 Nguyen Van Tuan Nguyen Van Hieu +5 位作者 Nguyen Khac Bang Pham Hoang Hai Nguyen Khanh Van Le Vinh Ha Tran Thi Hoa Lê Trọng Hiếu 《Atmospheric and Climate Sciences》 CAS 2023年第2期175-200,共26页
Spatio-temporal analysis of drought provides valuable information for drought management and damage mitigation. In this study, the Standardized Precipitation Index at the time scale of 6 months (SPI-6) is selected to ... Spatio-temporal analysis of drought provides valuable information for drought management and damage mitigation. In this study, the Standardized Precipitation Index at the time scale of 6 months (SPI-6) is selected to reflect drought conditions in the North-Eastern coastal region of Vietnam. The drought events and their characteristics from 1981 to 2019 are detected at 9 meteorological stations and 10 Chirps rainfall stations. The spatio-temporal variation of drought in the study region is analyzed on the basis of the number, duration, severity, intensity, and peak of the detected drought events at the 19 stations. The results show that from 1981 to 2019 the drought events mainly occurred with 1-season duration and moderate intensity and peak. The number, duration, severity, and peak of the drought events were the greatest in the period 2001-2010 and were the smallest in the period 2011-2019. Among the 19 stations, the drought duration tends to decrease at 11 stations, increase at 7 stations, and has a slight variant at 1 station;the drought severity tends to decrease at 14 stations, increase at 4 stations, and has not a significant trend at 1 station;the drought intensity tends to decrease at 17 stations, increase at 1 station, and has a slight variant at 1 station;and the drought peak tends to decrease at 18 stations and increase at 1 station. 展开更多
关键词 Spatio-Temporal Analysis of Drought Standardized Precipitation index (spi) Drought Characteristics
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致癌基因SPI1的泛癌分析鉴定及其在胶质瘤中的预后价值和免疫功能
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作者 阿衣努尔·玉山 哈尼克孜·吐尔逊 +3 位作者 王渭娜 范海 热孜万古力·热西提 朱国华 《中华神经外科疾病研究杂志》 CAS 2024年第3期30-38,共9页
目的探讨SPI1在胶质瘤中的预后价值及其与免疫抑制的关系。方法使用GEPIA2数据库评估SPI1 mRNA在TCGA肿瘤中的表达及临床预后价值。基于cBioPortal数据库分析GBM中SPI1与其他mRNAs的相关性,选择与SPI1最显著正相关的前200个基因通过Meta... 目的探讨SPI1在胶质瘤中的预后价值及其与免疫抑制的关系。方法使用GEPIA2数据库评估SPI1 mRNA在TCGA肿瘤中的表达及临床预后价值。基于cBioPortal数据库分析GBM中SPI1与其他mRNAs的相关性,选择与SPI1最显著正相关的前200个基因通过Metascape数据库进行GO和KEGG通路分析。利用ssGSEA算法评估TCGA–GBM中SPI1 mRNA表达与免疫浸润细胞的Spearman相关性。利用CAMOIP数据库进行免疫细胞浸润评分。结果SPI1在胶质瘤中高表达并与预后相关。此外,SPI1被预测参与巨噬细胞激活,以及免疫反应的正向调节。SPI1与大多数免疫细胞的浸润相关,同时,SPI1的高表达促进了巨噬细胞的极化。结论SPI1在胶质瘤免疫细胞浸润中发挥重要作用,并代表胶质瘤的有价值的预后生物标志物,是胶质瘤患者的潜在治疗靶点。 展开更多
关键词 胶质瘤 spi1基因 免疫浸润 生物标志物
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Spatiotemporal Analysis of Meteorological Drought Using Standardized Precipitation Index (SPI) in Gabiley Region, Somaliland
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作者 Abdisamad Abib Omar Jie-Lun Chiang Bashir Hassan Daud 《Journal of Geoscience and Environment Protection》 2023年第5期47-59,共13页
Drought is a common natural disaster worldwide, with varying durations, severity levels, and spatial extents. This study aimed to model the spatiotemporal variation of meteorological drought events in the Gabiley regi... Drought is a common natural disaster worldwide, with varying durations, severity levels, and spatial extents. This study aimed to model the spatiotemporal variation of meteorological drought events in the Gabiley region of Somaliland. The study utilized primary data collected from the meteorological station in Gabiley and CHIRPS (Climate Hazards Group InfraRed Precipitation with Station) data to develop the standardized precipitation index (SPI) at a 3-month timescale. The results of the study revealed that the study area was characterized by drought and received inadequate precipitation, resulting in catastrophic droughts that negatively impacted the socioeconomic situation of the community. Mild-to-severe meteorological drought events occurred every two to three years, with the most severe droughts occurring in 1998, 2002, 2009, 2015, and 2017. Specifically, the year 2015 experienced the most severe meteorological drought in the region during the studied period. The predominant type of drought was a mild year in the study area. The SPI was found to potentially identify meteorological drought, making it a useful tool for policymakers as they develop drought adaptation and mitigation policies. This study provides valuable information that can benefit local authorities and policymakers in creating drought mitigation and adaptation strategies in the Gabiley region. 展开更多
关键词 Meteorological Drought spi CHRIPS RAINFALL Gabiley
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基于SPI的1961—2020年昌吉地区作物生长季气象干旱时空特征研究
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作者 阿帕尔·肉孜 阿吉古丽·沙依提 +1 位作者 叶尔克江·霍依哈孜 黄秋霞 《沙漠与绿洲气象》 2024年第2期163-168,共6页
基于昌吉地区1961—2020年的气象资料分析作物生长季标准化降水指数(SPI-7)的年际和年代际变化特征,揭示作物生长季干旱发生频率和强度。结果表明:1961—2020年昌吉地区作物生长季水分呈增加趋势,标准化降水指数以0.08/10 a的速率增加... 基于昌吉地区1961—2020年的气象资料分析作物生长季标准化降水指数(SPI-7)的年际和年代际变化特征,揭示作物生长季干旱发生频率和强度。结果表明:1961—2020年昌吉地区作物生长季水分呈增加趋势,标准化降水指数以0.08/10 a的速率增加。气象干旱呈干—湿—干的年代际变化趋势,其中在1981年发生突变。干旱强度呈增加趋势,干旱发生面积呈弱减少趋势。东部地区是干旱高发区,但以轻旱为主;西部地区则是中旱、重旱和特旱高发区。昌吉地区的气象干旱存在6、9、16 a的周期震荡,与历史灾情具有很好的吻合性。 展开更多
关键词 作物生长季 气象干旱 标准化降水指数(spi) 干旱强度 干旱频率
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标准化降水指数(SPI)和Z指数在淮北平原适用性研究
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作者 张美娜 王发信 +4 位作者 吕海深 丁钰童 徐荣艳 王婉婉 王振龙 《节水灌溉》 北大核心 2024年第9期82-88,95,共8页
淮北平原是我国重要的粮食生产基地,分析其干旱时空变化特征和不同干旱指数的适用性,提高淮北平原抗旱风险能力,对农业生产和旱情监测具有重要意义。利用淮北平原20个气象站1962-2021年降水资料,计算了年尺度和季尺度的标准化降水指数(S... 淮北平原是我国重要的粮食生产基地,分析其干旱时空变化特征和不同干旱指数的适用性,提高淮北平原抗旱风险能力,对农业生产和旱情监测具有重要意义。利用淮北平原20个气象站1962-2021年降水资料,计算了年尺度和季尺度的标准化降水指数(SPI)和Z指数,分析了两指数在淮北平原的一致性以及时空变化特征的差异性,并结合历史旱情资料对比分析,进一步研究两种干旱指数的适用性。结果表明,两指数在年、季尺度下的淮北平原均呈现较好一致性,并与该区降雨存在极强相关性;时间尺度上,两指数均在年以及夏冬两季呈缓慢湿润化趋势,春秋两季呈不显著干旱化趋势;空间尺度上,Z指数监测的干旱发生面积和发生频率均高于SPI指数;与历史旱情资料对比分析结果表明,与SPI指数相比Z指数监测结果具有一定持续性,不易出现异常现象,且与实际较为一致。综合分析表明,Z指数在淮北地区的干旱监测适用性较好。 展开更多
关键词 标准化降水指数 Z指数 干旱指数 适用性 淮北平原
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Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study 被引量:1
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作者 Ya-Jie Teng Ying-Xue Yang +5 位作者 Jing-Jing Yang Qiu-Yan Lu Jia-Yi Shi Jian-Hao Xu Jie Bao Qing-Hua Wang 《World Journal of Gastrointestinal Endoscopy》 2024年第2期55-63,共9页
BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses met... BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal cancers.AIM To investigate the potential association between the TyG index and CPs,as the relation between them has not been documented.METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional study.After excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without CPs.Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs.The TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports.RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<0.0001.However,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=0.1521.CONCLUSION Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC. 展开更多
关键词 Triglyceride-glucose index Colorectal polyps Colorectal cancer Insulin resistance Cross-sectional study
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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:1
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data
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On traceable iterated line graph and hamiltonian path index
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作者 NIU Zhao-hong XIONG Li-ming YANG Wei-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期239-252,共14页
Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥2.In this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characteri... Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥2.In this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian path.As applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph. 展开更多
关键词 iterated line graph TRACEABLE hamiltonian index hamiltonian path index
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高速SPI接口在SIM卡上的应用设计
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作者 王海涛 衣莉莉 +1 位作者 孙阳阳 刘觅 《邮电设计技术》 2024年第6期47-50,共4页
通过对当前物联网的安全威胁进行深入分析,发现SIM卡安全方案在实际使用过程中存在的一些问题。鉴于此,结合安全元件(SE)的SPI接口优点,设计了SPI接口应用在SIM卡上的全新方案,详述了该方案的软硬件架构,最后阐述了该方案在实际应用中... 通过对当前物联网的安全威胁进行深入分析,发现SIM卡安全方案在实际使用过程中存在的一些问题。鉴于此,结合安全元件(SE)的SPI接口优点,设计了SPI接口应用在SIM卡上的全新方案,详述了该方案的软硬件架构,最后阐述了该方案在实际应用中所具有的优势。 展开更多
关键词 spi SIM SE 物联网安全
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An evaluation of ureteral diameter ratio and vesicoureteral reflux index in the treatment of primary vesicoureteral reflux
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作者 Yusuf Atakan Baltrak Nebil Akdogan +3 位作者 Mutlu Deger Volkan Izol Ibrahim Atilla Aridogan Nihat Satar 《Asian Journal of Urology》 CSCD 2024年第3期437-442,共6页
Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and co... Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and compare the ureter diameter ratio(UDR)and VUR index(VURx)of patients treated with endoscopic injection(EI)and ureteroneocystostomy(UNC)methods in the pediatric age group due to primary VUR.Methods:Patients under the age of 18 years old who underwent EI and UNC with the diagnosis of primary VUR between January 2011 and September 2021 were determined as the participants.The UDR was assessed using voiding cystourethrography,and the VURx score was determined prior to treatment based on hospital records included in the study.Results:A total of 255 patients,60(23.5%)boys and 195(76.5%)girls,with a mean age of 76.5(range 13.0e204.0)months,were included in the study.EI was applied to 130(51.0%)patients and UNC was applied to 125(49.0%)patients due to primary VUR.The optimum cut-off for the distal UDR was obtained as 0.17 with sensitivity and specificity of 73.0%and 63.0%,respectively.The positive and negative predictive values were 66.0%and 70.0%,respectively.Conclusion:When the UDR and VURx score are evaluated together for the surgical treatment of primary VUR in the pediatric age group,it is thought that it may be useful in predicting the clinical course of the disease and evaluating surgical treatment options. 展开更多
关键词 Distalureter diameter ratio Vesicoureteral reflux Vesicoureteral reflux index management Vesicoureteral reflux index
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Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation
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作者 Qing YAN Jia-Qi LIANG +5 位作者 Yi-De YUAN Yuan LI Jia-Li FAN Wen-Huan WU Pan XU Jia-Hong XUE 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第2期200-210,共11页
BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence... BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an Jiaotong University were included in this study.The participants were grouped based on cumulative TyG index values tertiles within 3 months after ablation.Cox regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF recurrence.The predictive value of all risk factors was assessed by receiver operating curve analysis.RESULTS There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values tertiles.After adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,P<0.001)had a higher risk of AF recurrence than those in the low cumulative TyG index group.The restricted cubic spline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index values.When considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after RFCA.Monitoring longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence. 展开更多
关键词 ATRIAL FIBRILLATION index
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Lower Extremity Arterial Disease in Patients with Type 2 Diabetes: Prevalence and Associated Factors at the Libreville University Hospital Center
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作者 Allognon Mahutondji Christian Ayo Bivigou Elsa +13 位作者 Ntoutoume Mvé Dylan Anthony N’nang Jean-Fidel Kinga Armel Mpori Jamila Myrtille Akagah Kondé Christelle Ndoume Obiang Francis Yékini Carole Fadylath Ndjibah Alakoua Cajole Ludvine Babongui Boussougou Latifah Mipinda Jean-Bruno Moubamba Franck Ecke Nzengue Jean-Emmanuel Houenassi Dèdonougbo Martin Boguikouma Jean-Bruno 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期295-308,共14页
Introduction: Lower extremity arterial disease in diabetic patients has distinct characteristics. Objectives: To study the hospital frequency of lower extremity arterial disease and identify associated factors in diab... Introduction: Lower extremity arterial disease in diabetic patients has distinct characteristics. Objectives: To study the hospital frequency of lower extremity arterial disease and identify associated factors in diabetic patients at the Libreville University Hospital Center (CHUL). Materials and Methods: This was a cross-sectional study conducted from July 1, 2023, to January 31, 2024, in the endocrinology department of the CHUL. All patients with type 2 diabetes over the age of 18 admitted to this department, regardless of the reason for hospitalization, who provided informed consent, were included. Socio-demographic data and cardiovascular risk factors were recorded. Personal and family cardiovascular history and functional symptoms were investigated. The physical examination included measuring blood pressure, heart rate, and the ankle-brachial index in all patients. Results: A total of 219 patients were included, of whom 75 had lower extremity arterial disease, representing a prevalence of 34.24%. It was compensated in 28 cases (37.33%) and decompensated in 39 patients (52%). In eight cases (10.67%), there was critical chronic ischemia. Cardiovascular risk factors associated with diabetes were physical inactivity (89.5%), hypertension (55.25%), overweight (49.77%), obesity (22.84%), and smoking (10.04%). In multivariate analysis, only hypertension (OR = 2.09;95% CI: 1.05 - 4.17;p = 0.035) and LDL cholesterol (OR = 2.75;95% CI: 1.10 - 6.85;p = 0.03) were significantly associated with lower extremity arterial disease in diabetics at the University Hospital of Libreville. Conclusion: Lower extremity arterial disease is common in diabetic patients at the University Hospital of Libreville. It is often asymptomatic, thus requiring systematic screening.[-rId11-] 展开更多
关键词 Lower Extremity Arterial Disease DIABETES HYPERTENSION Ankle-Brachial index GABON
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Applying Source Parameter Imaging (SPI) to Aeromagnetic Data to Estimate Depth to Magnetic Sources in the Mamfe Sedimentary Basin
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作者 Eric N. Ndikum Charles T. Tabod 《International Journal of Geosciences》 CAS 2024年第1期1-11,共11页
Aeromagnetic data over the Mamfe Basin have been processed. A regional magnetic gridded dataset was obtained from the Total Magnetic Intensity (TMI) data grid using a 3 × 3 convolution (Hanning) filter to remove ... Aeromagnetic data over the Mamfe Basin have been processed. A regional magnetic gridded dataset was obtained from the Total Magnetic Intensity (TMI) data grid using a 3 × 3 convolution (Hanning) filter to remove regional trends. Major similarities in magnetic field orientation and intensities were observed at identical locations on both the regional and TMI data grids. From the regional and TMI gridded datasets, the residual dataset was generated which represents the very shallow geological features of the basin. Processing this residual data grid using the Source Parameter Imaging (SPI) for magnetic depth suggests that the estimated depths to magnetic sources in the basin range from about 271 m to 3552 m. The highest depths are located in two main locations somewhere around the central portion of the study area which correspond to the area with positive magnetic susceptibilities, as well as the areas extending outwards across the eastern boundary of the study area. Shallow magnetic depths are prominent towards the NW portion of the basin and also correspond to areas of negative magnetic susceptibilities. The basin generally exhibits a variation in depth of magnetic sources with high, average and shallow depths. The presence of intrusive igneous rocks was also observed in this basin. This characteristic is a pointer to the existence of geologic resources of interest for exploration in the basin. 展开更多
关键词 Mamfe Basin Aeromagnetic Data Source Parameter Imaging (spi) Depth to Magnetic Sources
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