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The Probable Cause for Nesting Pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar Beach, North East Coast of Andaman Island, India
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作者 Arun Malarvizhi M. M. Ilaamurughu P. M. Mohan 《Open Journal of Marine Science》 2023年第1期7-27,共21页
The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with th... The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with the nesting behaviour of the Olive Ridley turtles. In the present study, characteristics of the breeding beach and nesting pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of Andaman Islands were investigated, during the nesting periods 2016-2017. The study area hosts Olive Ridley, the dominant sea turtles with more than 300 individuals nesting each year. For this study, the number of sea turtles visited, nested, the sediment characters, salinity, and temperature were taken. The exposed sandy nesting beach characteristics are prone to varying degrees of morphological changes every day. The results depict that even though similar grain size (Coarse Sand to Fine Sand and Very well sorted to Poorly Sorted), with an ambient incubating temperature, pH and salinity with wide nesting area, the selective nesting in the particular location of the beach identified because of comfortable energy conditions in the waters (1.5 m/s) favours the female turtles to reach the beach at the preferable site of Ramnagar and nest. 展开更多
关键词 Sea turtle Olive Ridley Ramnagar Beach nesting Environment Morphological Changes Sand Grain HATCHLING North Andaman
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Epi-1对脂多糖诱导人牙髓干细胞炎症反应的影响
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作者 罗宇仪 赵望泓 梁悦娥 《兰州大学学报(医学版)》 2024年第10期13-19,35,共8页
目的研究生物活性肽Epi-1在脂多糖(LPS)诱导下的炎症微环境中对人牙髓干细胞(hDPSC)表达炎症因子的影响和可能机制。方法通过组织块酶消化法分离、培养hDPSC,并通过流式细胞术鉴定。利用CCK-8试剂检测Epi-1对hDPSC细胞活性的影响,筛选... 目的研究生物活性肽Epi-1在脂多糖(LPS)诱导下的炎症微环境中对人牙髓干细胞(hDPSC)表达炎症因子的影响和可能机制。方法通过组织块酶消化法分离、培养hDPSC,并通过流式细胞术鉴定。利用CCK-8试剂检测Epi-1对hDPSC细胞活性的影响,筛选出适宜的浓度。实验分为4组,分别为空白对照组(不含LPS和Epi-1)、LPS组(1.0μg/mL LPS)、2.5μg/mL Epi-1组(1.0μg/mL LPS和2.5μg/mL Epi-1)和5.0μg/mL Epi-1组(1.0μg/mL LPS和5.0μg/mL Epi-1),通过实时荧光定量聚合酶链式反应检测Epi-1对hDPSC白介素(IL)-6、IL-1β、IL-8基因表达的影响,进一步通过蛋白质免疫印迹法检测核因子κB信号通路关键蛋白p65、p-p65的表达情况,使用荧光探针检测活性氧生成情况。采用SPSS 22.0分析数据。结果在2.5、5.0μg/mL的质量浓度下,Epi-1无明显细胞毒性;Epi-1可显著降低LPS诱导后hDPSC中IL-6、IL-1β、IL-8的mRNA表达(P<0.01),减少p-p65的表达(P<0.05)和活性氧的生成(P<0.001)。结论Epi-1可能通过抑制核因子κB信号通路的激活和减轻氧化应激反应,从而降低LPS诱导的hDPSC的炎症反应。 展开更多
关键词 人牙髓干细胞 炎症 epi-1 核因子ΚB 牙髓炎 生物活性肽
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Implementation of a Nesting Repair Technology for Transportation Pipeline Repair
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作者 Yijun Gao Yong Wang +2 位作者 Qing Na Jiawei Zhang Aixiang Wu 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2443-2458,共16页
Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeli... Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeline transportation typically plays a decisive role in the safety and stability of the entirefilling system.Because thefilling slurry contains a large percentage of solid coarse particles,the involved pipeline is typically eroded and often damaged during such a process.A possible solution is the so-called nesting repair technology.In the present study,nesting a 127 mm outer diameter pipeline in 151 mm inner diameter borehole is considered to meet the repair objective.First,by using the rheological theory,the pipeline transmission resistance and self-flow conveying range are calculated under different working conditions.It is shown that the pipeline transmission resistance is larger when the inner diameter of casing is 80 mm,and the limitflow rate of vertical pipeline self-flow is 120 m^(3)/h;moreover,when the pipeline diameter is 100 mm and theflow rate is 140 m^(3)/h,the self-flow conveying can be satisfied in most of the underground−455 m stage.Accordingly,a plan is presented for the nesting repair strategy,based on the installation of a drill bit under the casing and lowering the casing into the borehole as if it were a drill pipe.Finally,the outcomes of such a strategy are verified.Thefillingflow rate range using the new pipelines is found to be in the range from 188.60 to 224.39 m^(3)/h,and its averagefillingflow rate reaches 209.83 m^(3)/h when conveying 2319.6 m long-distance quarry. 展开更多
关键词 BOREHOLE nesting repair pipeline transmission resistance flow rate
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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment
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作者 Macarena Castro Andrés De la Cruz +1 位作者 Nuria Martin-Sanjuan Alejandro Pérez-Hurtado 《Avian Research》 SCIE CSCD 2024年第1期55-59,共5页
Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be... Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding habitat.Here it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they offer.Following this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ nests.More than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both years.The best model for both species indicates that the presence of shells is the factor that most correlates with the location of nests.The probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little Tern.The result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint. 展开更多
关键词 Habitat management Nest site selection Saltpan restoration Shell supplementation SHOREBIRDS
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T_(2)WI 3D-SPACE+RS-EPI DWI检查对直肠癌术前肿瘤淋巴结分期诊断准确率的影响
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作者 王俊波 王晋君 +2 位作者 丁建峰 张崇杰 焦玉泉 《中国CT和MRI杂志》 2024年第6期142-144,共3页
目的 探究T_(2)WI 3D-SPACE联合RS-EPI DWI检查在直肠癌术前肿瘤淋巴分期诊断准确率的影响。方法 收集2020年7月-2022年2月在本院确诊直肠癌并进行影像学检查的96名患者作为此次的研究对象,将所有的研究对象随机进行分组,对照组选择T_(2... 目的 探究T_(2)WI 3D-SPACE联合RS-EPI DWI检查在直肠癌术前肿瘤淋巴分期诊断准确率的影响。方法 收集2020年7月-2022年2月在本院确诊直肠癌并进行影像学检查的96名患者作为此次的研究对象,将所有的研究对象随机进行分组,对照组选择T_(2)WI 3D-SPACE进行检查,研究组采用T_(2)WI3D-SPACE联合RS-EPI DWI进行检查,由盲选形式经检查结果呈现给2位资历较高的临床医师对直肠癌术前肿瘤淋巴分期的结果进行鉴别,分析两组肿瘤淋巴结分期阳性诊断的准确性的差异。结果 研究组在直肠癌术前是肿瘤淋巴结分期的准确率高于对照组,尤其是在T3期和T4期,对照组的准确率分别为75.61%和84.38%,研究组为97.56%和100%,有差异纳入统计(P<0.05);对照组的总准确率和淋巴结阳性准确率分别为70%和79.55%,研究组的总淮确率和淋巴结阳性准确率分别为95%和97.73%,研究组总准确率和淋巴结阳性准确率高于对照组,有差异纳入统计(P<0.05)。结论 T_(2)WI 3D-SPACE联合RS-EPI DWI检查能提高直肠癌术前肿瘤淋巴分期诊断的准确性,具有较高的诊断价值,可用于直肠癌术前的肿瘤淋巴结的扫描,为临床医生的确诊提供了重要的理论依据。 展开更多
关键词 T_(2)WI 3D-SPACE RS-epi DWI 直肠癌 肿瘤淋巴分期 诊断准确率
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基于QuEChERS-HPLC∕MRM-IDA-EPI技术测定茄子中11种农药残留
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作者 汤逸飞 屠雨晨 +2 位作者 陈欣慰 黄芳 张国平 《上海农业学报》 2024年第3期92-100,共9页
利用乙腈溶液提取10.0 g茄子均质化样品,经乙二胺-N-丙基硅烷、石墨化炭黑、硫酸镁和氯化钠净化后利用快速前处理-高效液相∕多反应监测-信息依赖-增强型质谱扫描(QuEChERS-HPLC∕MRM-IDA-EPI)分析方法识别茄子中11种农药残留化合物的... 利用乙腈溶液提取10.0 g茄子均质化样品,经乙二胺-N-丙基硅烷、石墨化炭黑、硫酸镁和氯化钠净化后利用快速前处理-高效液相∕多反应监测-信息依赖-增强型质谱扫描(QuEChERS-HPLC∕MRM-IDA-EPI)分析方法识别茄子中11种农药残留化合物的结构和合理的片段化离子,采用+MRM-IDA-EPI模式,外标法定量。结果显示:该方法在10—250μg∕L茄子加标基质内线性关系良好,回归方程相关系数(r)为0.9949—0.9999;在0.01—0.25 mg∕kg范围内添加回收率(P)为69.02%—127.49%,相对标准偏差(RSD)为1.48%—13.56%。可同时触发EPI模式,通过判断准分子离子峰、加钠离子峰或同位素离子峰丰度比等方式,对可能呈现的[M+H]+、[M+Na]+、氯取代或溴取代特征碎片离子进行判别。综上,研究可为蔬菜中11种农药残留的监控和风险评估等提供一种快速、高效和可靠的分析手段。 展开更多
关键词 高效液相 多反应监测-信息依赖-增强型质谱 茄子 农药残留 同位素离子峰
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基于光场EPI图像栈的6D位姿估计方法 被引量:2
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作者 李扬 张旭东 +1 位作者 孙锐 范之国 《电子测量与仪器学报》 CSCD 北大核心 2023年第4期122-130,共9页
光场相机单次拍摄可以同时记录光线的强度与方向信息,相较于RGB相机能够更好地揭示场景的三维结构和几何特征,在目标6D位姿估计领域具有独特优势。针对现有RGB位姿估计方法存在复杂场景下检测精度低、鲁棒性差的问题,本文首次提出了一... 光场相机单次拍摄可以同时记录光线的强度与方向信息,相较于RGB相机能够更好地揭示场景的三维结构和几何特征,在目标6D位姿估计领域具有独特优势。针对现有RGB位姿估计方法存在复杂场景下检测精度低、鲁棒性差的问题,本文首次提出了一种基于光场图像的端到端卷积神经网络目标位姿估计方法。该方法首先利用双路EPI编码模块实现高维光场数据的处理,通过重构出光场EPI图像栈和引入水平和垂直EPI卷积算子,提高对光场空间角度信息关联的建模能力,并由双分支孪生网络进行光场图像的浅层特征提取。其次,设计了带跳跃连接的特征聚合模块,对串联后的水平和垂直方向光场EPI浅层特征进行全局上下文聚合,使网络在逐像素关键点位置预测时有效结合全局和局部特征线索。针对光场数据不足问题,本文使用Lytro Illum光场相机采集真实场景,构建了一个丰富且场景复杂的光场位姿数据集——LF-6Dpose。在光场位姿数据集LF-6Dpose上的实验结果表明,该方法在ADD-S和2D Projection指标下平均位姿检测精度分别为57.61%和91.97%,超越了其他基于RGB的先进方法,能够更好地解决复杂场景下的目标6D位姿估计问题。 展开更多
关键词 光场 6D位姿估计 光场位姿数据集 epi图像栈 特征聚合模块 关键点
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磁共振成像RS-EPI序列在眼眶肿瘤及肿瘤样病变中的诊断价值
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作者 胡梅 张玲 刘俊 《分子影像学杂志》 2023年第5期868-872,共5页
目的研究磁共振成像分段读出平面回波成像(RS-EPI)序列在诊断眼眶肿瘤及肿瘤样病变中的应用价值。方法本研究为回顾性研究,以2016年12月~2018年12月在我院诊断并治疗的眼眶肿瘤及肿瘤样病变患者60例作为研究对象,所有患者均采取3T磁共... 目的研究磁共振成像分段读出平面回波成像(RS-EPI)序列在诊断眼眶肿瘤及肿瘤样病变中的应用价值。方法本研究为回顾性研究,以2016年12月~2018年12月在我院诊断并治疗的眼眶肿瘤及肿瘤样病变患者60例作为研究对象,所有患者均采取3T磁共振扫描仪(MAGNETOM Trio Tim)进行扫描,分别比较RS-EPI以及单次激发平面回波成像(SS-EPI)序列图像质量定性评分、图像质量定量评分的差异。分析RS-EPI序列及SS-EPI序列对于眼眶肿瘤及肿瘤样病变诊断效能之间的差异。结果两种方法对观察者组患者脂肪抑制情况之间的差异无统计学意义(P>0.001),RS-EPI序列诊断方法对于观察者组患者的正常解剖结构的显示能力、伪影情况以及图像综合质量评分高于SS-EPI序列(P<0.001);两种方法对观察者组患者玻璃体表观扩散系数(ADC)、脑干ADC脂的差异无统计学意义(P>0.05),RS-EPI序列诊断方法对于观察者组患者眼球前后、眼球左右的几何变形情况及信噪比低于SS-EPI序列(P<0.001);RS-EPI序列对于眼眶肿瘤及肿瘤样病变的诊断敏感度高于SS-EPI序列(P<0.05);ROC曲线显示,RS-EPI序列对于眼眶肿瘤及肿瘤样病变的曲线下面积高于SS-EPI序列(P<0.001)。结论磁共振成像RS-EPI序列可有效提升眼眶肿瘤及肿瘤样病变的图像质量以及诊断敏感度。 展开更多
关键词 RS-epi序列 SS-epi序列 图像质量 磁共振成像 眼眶肿瘤
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Recurrence after spontaneous separation of epiretinal membrane in a young woman:a case report 被引量:1
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作者 Qiao-Zhu Zeng Wen-Zhen Yu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期476-478,共3页
Dear Editor,We report a case of recurrence after spontaneous separation of epiretinal membrane (ERM) in a young woman with suspected retinal vasculitis.ERM is defined as the fibrocellular membrane that proliferates on... Dear Editor,We report a case of recurrence after spontaneous separation of epiretinal membrane (ERM) in a young woman with suspected retinal vasculitis.ERM is defined as the fibrocellular membrane that proliferates on the inner surface of neurosensory retina at the macular area.Idiopathic ERM(iERM) usually occurs without a clearly identifiable cause in patients of more than 50 years of age and a great discrepancy in its prevalence from 1.02%to 28.9%among different ethnic groups were noted in previous epidemiologic studies^([1-3]). 展开更多
关键词 SEPARATION epi YOUNG
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一种三层EPI结构SGT MOSFET设计 被引量:1
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作者 商世广 郭雄雄 +2 位作者 张雨 王洋菲 俱帅 《西安邮电大学学报》 2023年第4期36-43,共8页
提出了一种三层外延(Epitaxy,EPI)结构的屏蔽栅沟槽金属氧化物半导体场效应晶体管(Shielded Gate Trench Metal-Oxide-Semiconductor Field-Effect Transistor,SGT MOSFET)设计方案。利用Sentaurus TCAD工具,将单层EPI结构调整为三层EP... 提出了一种三层外延(Epitaxy,EPI)结构的屏蔽栅沟槽金属氧化物半导体场效应晶体管(Shielded Gate Trench Metal-Oxide-Semiconductor Field-Effect Transistor,SGT MOSFET)设计方案。利用Sentaurus TCAD工具,将单层EPI结构调整为三层EPI结构,通过控制变量法拉偏三层EPI结构的外延层厚度、电阻率等参数,仿真分析其参数变化对SGT MOSFET性能的影响。仿真结果表明,在相同的原胞尺寸条件下,与单层EPI结构SGT MOSFET相比,三层EPI结构SGT MOSFET通过横向电场调制作用降低了纵向电场的峰值,击穿电压提高9.5%,比导通电阻降低15.6%,有效地提高了器件的电学性能。 展开更多
关键词 SGT MOSFET 三层epi 品质因数 击穿电压 比导通电阻
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芫花根中菖蒲烷型倍半萜4-epi-15-hydroxyacorenone抗炎机制研究
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作者 马欣宇 徐瑶瑶 +3 位作者 王庆超 宗明月 宋少江 赵烽 《亚太传统医药》 2023年第9期13-19,共7页
目的:对从芫花根中分离的菖蒲烷型倍半萜4-epi-15-hydroxyacorenone进行抗炎活性研究,探讨其抗炎分子机制,为芫花药用资源的合理开发利用提供理论依据。方法:采用RAW 264.7巨噬细胞建立炎症模型,分为空白组、模型组、给药组。通过Gries... 目的:对从芫花根中分离的菖蒲烷型倍半萜4-epi-15-hydroxyacorenone进行抗炎活性研究,探讨其抗炎分子机制,为芫花药用资源的合理开发利用提供理论依据。方法:采用RAW 264.7巨噬细胞建立炎症模型,分为空白组、模型组、给药组。通过Griess法检测4-epi-15-hydroxyacorenone对脂多糖(LPS)诱导的RAW 264.7巨噬细胞释放炎症介质一氧化氮(NO)的抑制活性,运用噻唑蓝(MTT)比色法检测细胞毒性,酶联免疫吸附测定法(ELISA)检测化合物对炎症介质前列腺素E2(PGE2)、炎症因子肿瘤坏死因子-α(TNF-α)以及白细胞介素-6(IL-6)的抑制作用,蛋白免疫印迹法(Western Blot)检测化合物对炎症蛋白iNOS和COX-2高表达的影响,对核转录因子κB(NF-κB)信号通路中IκB-α蛋白的降解以及丝裂原活化蛋白激酶(MAPKs)信号通路中ERK、JNK、p38蛋白磷酸化的抑制作用。结果:与空白组相比,模型组经LPS刺激后炎症因子、炎症介质的释放,炎症蛋白的表达均显著增加(P<0.01),与模型组相比,给药组菖蒲烷型倍半萜4-epi-15-hydroxyacorenone可阻断ERK、JNK蛋白磷酸化(P<0.01),抑制iNOS和COX-2的高表达并且呈良好的剂量依赖关系(P<0.01),显著降低炎症因子TNF-α、IL-6以及炎症介质NO、PGE2的释放(P<0.01),但对NF-κB信号通路的激活无任何影响。结论:4-epi-15-hydroxyacorenone主要通过调控MAPKs信号通路的激活,下调LPS诱导的炎症蛋白的高表达,抑制RAW 264.7巨噬细胞中炎症介质以及炎症因子的释放发挥抗炎作用。 展开更多
关键词 芫花根 4-epi-15-hydroxyacorenone 抗炎 NF-ΚB MAPKS
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基于UPLC-MS/MS建立早产儿血清25-(OH)D3和3-epi-25-(OH)D3检测新方法及临床初步应用 被引量:3
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作者 刘浩 彭勇 +3 位作者 尹一帆 叶亮 陈敏 苗静琨 《现代检验医学杂志》 CAS 2023年第3期170-175,共6页
目的建立血清25-羟维生素D_(3)[25-hydroxyvitamin D_(3),25-(OH)D_(3)]及3-epi-25-羟维生素D_(3)[3-epi-25-hydroxyvitamin D_(3),3-epi-25-(OH)D_(3)]超高效液相色谱-串联质谱检测新方法(ultra-performance liquid chromatography-tan... 目的建立血清25-羟维生素D_(3)[25-hydroxyvitamin D_(3),25-(OH)D_(3)]及3-epi-25-羟维生素D_(3)[3-epi-25-hydroxyvitamin D_(3),3-epi-25-(OH)D_(3)]超高效液相色谱-串联质谱检测新方法(ultra-performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS),并在早产儿中开展初步应用。方法采用液-液萃取法提取化合物,五氟苯基丙基(pentafluorophenyl propyl,PFPP)色谱柱分离25-(OH)D_(3)与3-epi-25-(OH)D_(3);从最低定量限、线性关系、精密度与准确度等四个方面对新建方法进行验证,并对134例早产儿血清样本进行检测分析。结果25-(OH)D_(3)及3-epi-25-(OH)D_(3)的最低定量限分别为6.05±0.78 nmol/L,1.48±0.20 nmol/L;线性范围3.78~480.00 nmol/L,1.00~128.00 nmol/L;相关系数r2为0.9922,0.9928;25-(OH)D_(3)与3-epi-25-(OH)D_(3)低、中、高浓度质控品的日内精密度和日间精密度均小于15.00%;回收率109.92%,102.25%,98.76%;97.75%,95.25%,99.80%。134例早产儿血清25-(OH)D_(3)平均浓度22.35±13.28nmol/L,3-epi-25-(OH)D_(3)平均浓度5.43±4.35 nmol/L;3-epi-25-(OH)D_(3)占总25-(OH)D_(3)的平均比例为19.96%±12.08%,范围0.00%~60.62%。以25-(OH)D_(3)计算,维生素D(Vitamin D,Vit D)缺乏率、不足率、充足率分别为78.36%,19.40%,2.24%;以总25-(OH)D_(3)计算,Vit D缺乏率、不足率、充足率分别为65.67%,26.12%,8.21%;二者Vit D缺乏率及充足率的比较,差异均有统计学意义(χ^(2)=5.351,1.719,4.823,均P<0.05)。结论本研究建立的UPLC-MS/MS检测法性能良好且能精准检测早产儿血清25-(OH)D_(3)浓度,在早产儿Vit D评估方面具有较好的应用价值。 展开更多
关键词 维生素D 3-epi-25-羟维生素D3 超高效液相色谱-串联质谱 早产儿
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The effects of climate and land use change on the potential distribution and nesting habitat of the Lesser Adjutant in Nepal
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作者 Hem Bahadur Katuwal Hari Prasad Sharma +10 位作者 Prashant Rokka Krishna Prasad Bhusal Bishnu Prasad Bhattarai Sabina Koirala Sandeep Chhetri Luitel Shailendra Yadav Ganesh Sah Hem Sagar Baral Laxman Prasad Poudyal Lin Wang Rui-Chang Quan 《Avian Research》 SCIE CSCD 2023年第3期326-335,共10页
Climate change and land use change pose a threat to the world’s biodiversity and have significant impacts on the geographic distribution and composition of many bird species,but little is known about how they affect ... Climate change and land use change pose a threat to the world’s biodiversity and have significant impacts on the geographic distribution and composition of many bird species,but little is known about how they affect threatened large-sized waterbird species that rely on agricultural landscapes.To address this gap,we investigated how climate and land use changes influence the distribution and nesting habitats of the globally vulnerable Lesser Adjutant(Leptoptilos javanicus) in Nepal.Between 2012 and 2023,we collected distribution data from 24 districts and nesting site information from 18 districts.In a nation-wide breeding survey conducted in 2020,we documented a total of 581 fledglings from 346 nests in 109 colonies.The ensemble model predicted a current potential distribution of 15%(21,637 km2) and a potential nesting habitat of 13%(19,651 km2) for the species in Nepal.The highest predicted current suitable distribution and nesting habitat was in Madhesh Province,while none was predicted in Karnali Province.The majority of this predicted distributional and nesting habitat falls on agricultural landscapes(>70%).Our model showed a likely range expansion of up to 15%(21,573 km2) for the distribution and up to 12%(17,482 km2) for the nesting habitat under SSP5-8.5 scenarios for the 2070s.The range expansion is expected to occur mainly within the current distribution and breeding range(Tarai and some regions of Siwalk),particularly in Lumbini and Sudurpashchim provinces,and extend to the northern portions(Siwalik and Mid-hill regions) in other provinces.However,the current Protected Areas and Important Bird and Biodiversity Areas are inadequate for providing optimal habitats for the species.Although the model suggests range expansion,the use of such novel habitats is primarily contingent on the availability and protection of large-sized trees(particularly Bombax ceiba,observed in 65% of colonies) in agricultural regions where nesting occurs.Therefore,our research suggests that agricultural landscapes should be prioritized in management plans for the conservation of the Lesser Adjutant in Nepal. 展开更多
关键词 Agricultural landscapes Bombax ceiba Ensemble modeling Farmland bird IBA Nest site
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Modelling the nesting-habitat of threatened vulture species in the caucasus:An ecosystem approach to formalising environmental factors in species distribution models
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作者 Rustam Pshegusov Victoria Chadaeva 《Avian Research》 SCIE CSCD 2023年第4期572-585,共14页
Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formal... Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formalised the biotic predictors of nesting sites for four threatened Caucasian vultures by including species distribution models(wild ungulates,nesting tree species)as biotic layers in the vulture Maxent models.Maxent was applied in the R dismo package and the best set of the model parameters were defined in the R ENMeval package.Performance metrics were continuous Boyce index,Akaike's information criterion,the area under receiver operating curve and true skill statistics.We also calculated and evaluated the null models.Kernel density estimation method was applied to assess the overlap of vulture ecological niches in the environmental space.The accessibility of anthropogenic food resources was estimated using the Path Distance measure that considers elevation gradient.The availability of pine forests(Scots Pine)and wild ungulates(Alpine Chamois and Caucasian Goat)contributed the most(29.6%and 34.3%)to Cinereous Vulture(Aegypius monachus)nesting site model.Wild ungulate distribution also contributed significantly(about 46%)to the Bearded Vulture(Gypaetus barbatus)model.This scavenger nests in the highlands of the Caucasus at a minimum distance of 5–10 km from anthropogenic facilities.In contrast,livestock as a food source was most important in colony distribution of Griffon Vulture(Gyps fulvus).The contribution of distances to settlements and agricultural facilities to the model was 45%.The optimal distance from Egyptian Vulture(Neophron percnopterus)nesting sites to settlements was only 3–10 km,to livestock facilities no more than 15 km with the factor contribution of about 57%.Excluding the wild ungulate availability,the ecological niches of studied vultures overlapped significantly.Despite similar foraging and nesting requirements,Caucasian vultures are not pronounced nesting and trophic competitors due to the abundance of nesting sites,anthropogenic food sources and successful niche sharing. 展开更多
关键词 Caucasian vultures Ecological niche differentiation Maxent nesting sites Species distribution models
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Nesting Biology and Site Selection of Olive Ridley—A Coherence of Nature
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作者 Arun Malarvizhi P. M. Mohan 《Open Journal of Marine Science》 2023年第2期29-39,共11页
Nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. In the present study, characteristics of the breeding turtle, Olive Ridley (Lepidochely... Nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. In the present study, characteristics of the breeding turtle, Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of North Andaman Islands were investigated, for the nesting periods 2016-2017. Olive Ridley is the dominant sea turtles, with more than 300 individuals nesting every season with at least a 75% hatching success rate. It is one of the conducive, highly protective and undisturbed nesting sites for Olive Ridley on North Andaman coast. In the present study an initiative is made, to identify nature’s cues and the biological characteristics of Olive Ridley, which leads it to nest at Ramnagar beach, with a high hatchling success rate. 展开更多
关键词 Sea Turtle Olive Ridley Ramnagar Beach nesting Beach Sand Grain Hatch-ling North Andaman
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HBsAg ELISA+/HBV DNA NAT-献血者血清学与分子生物学特征分析 被引量:1
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作者 景媛媛 范云 +3 位作者 郭燕 张文娟 段勇 冯娜 《中国输血杂志》 CAS 2024年第4期412-416,共5页
目的 了解西安地区无偿献血人群HBsAg ELISA检测结果与HBV DNA检测结果不一致的标本相关血清学标志物的分布情况。方法 收集2022年11月1日—2023年4月30日陕西省血液中心HBsAg ELISA+/HBV DNA NAT-(ELISA+/NAT-)标本共计71份,对其采用... 目的 了解西安地区无偿献血人群HBsAg ELISA检测结果与HBV DNA检测结果不一致的标本相关血清学标志物的分布情况。方法 收集2022年11月1日—2023年4月30日陕西省血液中心HBsAg ELISA+/HBV DNA NAT-(ELISA+/NAT-)标本共计71份,对其采用电化学发光法检测乙肝血清学标志物,同时复检巢式PCR扩增HBV S区和C区基因片段。结果 双ELISA+/NAT-标本(n=30)巢式PCR检测阳性率远高于单ELISA+/NAT-标本(n=41)(60%vs 24.40%,P<0.05)。前者献血者100%为初次献血者,血清抗-HBc阳性率100%,血清学模式以1、4、5此3项阳性(80%)为主;后者献血者中31.7%为重复献血者,血清抗-HBc阳性率仅为19.51%,血清学模式以单2项阳性(43.90%)和全阴(36.58%)为主。结论 单ELISA+结果存在较多假阳性,导致不必要的血液报废;而NAT-标本可能存在低水平的HBV DNA,产生漏检风险。建议针对单HBsAg ELISA+/NAT-献血者,采用多套系统多种方法追溯检测,提高献血者HBV筛查的准确度,减少不必要的血液浪费。 展开更多
关键词 乙型肝炎表面抗原 无偿献血者 巢式PCR HBV DNA
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Herpes simplex virus gene therapy for dystrophic epidermolysis bullosa (DEB)
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作者 Alberto L Epstein 《四川生理科学杂志》 2023年第9期1724-1724,共1页
The FDA has recently approved Krystal biotech's beremagene gep erpavec (B-VEC, Vyjuvek) to treat the wounds of dystrophic epidermolysis bullosa (DEB) patients. This represents a giant step, not only toward the tre... The FDA has recently approved Krystal biotech's beremagene gep erpavec (B-VEC, Vyjuvek) to treat the wounds of dystrophic epidermolysis bullosa (DEB) patients. This represents a giant step, not only toward the treatment of this devastating disease, but also for the whole field of non-replicative (nr) recombinant HSV-1vectors for gene therapy. To view this Bench to Bedside, open or download the PDF. 展开更多
关键词 SIMPLEX PATIENTS epi
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考虑健康信念的游客分时预约行为分析
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作者 韩艳 晋翎钰 +1 位作者 韩佳乔 关宏志 《北京工业大学学报》 CAS CSCD 北大核心 2024年第7期845-853,共9页
为探索新冠肺炎疫情背景下景区分时预约策略、游客健康信念和风险预防行为之间的关系,需考虑健康信念,分析疫情防控期间游客分时预约行为机理。采用意愿调查法获取旅游信息、健康信念、分时预约行为意向数据,分析各预约时段余票比例和... 为探索新冠肺炎疫情背景下景区分时预约策略、游客健康信念和风险预防行为之间的关系,需考虑健康信念,分析疫情防控期间游客分时预约行为机理。采用意愿调查法获取旅游信息、健康信念、分时预约行为意向数据,分析各预约时段余票比例和门票预售期等信息对游客分时预约行为的影响。基于Nested Logit(NL)模型,建立考虑健康信念的游客游玩日期-时段预约选择联合模型,并进行敏感性分析。结果表明:预约信息、健康信念对游客预约节假日或非节假日游玩有显著影响;票价、各预约时段余票比例和健康信念对游客游玩时段预约选择行为有显著影响。游客感知新冠的严重性由1上升至5时,选择节假日出行的概率由30.46%下降至12.28%。研究可为景区分时预约策略的制定提供参考依据。 展开更多
关键词 交通工程 分时预约选择联合模型 健康信念 Nested Logit(NL)模型 分时预约 敏感性分析
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部分嵌套式设计在中医药“同病异治”疗效评价中的应用及方法学探索 被引量:1
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作者 冯硕 马继征 +3 位作者 郭玉峰 曹戬 胡晶 廖星 《中国中医药信息杂志》 CAS CSCD 2024年第4期26-30,共5页
目的本研究针对中医学同病异治、辨证论治的特征,引入部分嵌套式设计。方法部分嵌套式设计以复杂干预对照标准化治疗,中医组按“证型-治法-方药”分割为多个子集(存在嵌套结构),对照组采用标准化西医治疗(无嵌套结构);并以一项溃疡性结... 目的本研究针对中医学同病异治、辨证论治的特征,引入部分嵌套式设计。方法部分嵌套式设计以复杂干预对照标准化治疗,中医组按“证型-治法-方药”分割为多个子集(存在嵌套结构),对照组采用标准化西医治疗(无嵌套结构);并以一项溃疡性结肠炎“同病异治”数据为例,套用该设计类型并采用多水平模型分析。结果部分嵌套式设计符合“同病异治”诊疗特征并满足循证评价的设计要求,通过多水平模型可实现类似数据结构的分析。结论利用部分嵌套式设计能实现对“同病异治”整体效果的评价,可为中医药临床疗效评价提供方法学参考。 展开更多
关键词 部分嵌套式设计 同病异治 循证医学 疗效评价 方法学
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重大节假日出行方式选择模型研究
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作者 何永明 张磊 +2 位作者 魏堃 曹剑 王锦扬 《大连交通大学学报》 CAS 2024年第1期13-19,共7页
为优化节假日高速公路免费政策,选取出行者变量、出行方式相关变量和行程特性变量作为效用变量,构建了出行方式位于上层、出行距离位于下层的NL模型。利用弧弹性法分析不同收费标准和收费里程条件下出行者的行为特性,并利用场景仿真评... 为优化节假日高速公路免费政策,选取出行者变量、出行方式相关变量和行程特性变量作为效用变量,构建了出行方式位于上层、出行距离位于下层的NL模型。利用弧弹性法分析不同收费标准和收费里程条件下出行者的行为特性,并利用场景仿真评价多种收费组合对出行方式的影响。研究结果表明:提高收费标准,汽车出行比例会显著降低,且高速铁路承担了大部分的转移交通量。随着收费里程的增加,出行者逐渐倾向于出行成本较小的普通铁路。对长距离出行收费可以提升公共交通分担率,缓解节假日高速公路的交通拥堵。 展开更多
关键词 节假日出行 免费政策 Nested Logit模型 出行方式 场景仿真
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