Results 31 to 40 of about 17,610 (165)

Decoupling the Roles of Corticosterone in Mediating Effects of Methylmercury and Chytrid Fungus (Bd) on Amphibian Survival 解构皮质酮在介导甲基汞与壶菌 (Bd) 对两栖动物生存影响中的双重作用

open access: yesWildlife Letters, Volume 3, Issue 4, Page 143-151, December 2025.
Effects of methylmercury bioaccumulation on survival of Columbia Spotted Frogs were modified by sex and length and were mediated by corticosterone (a glucocorticoid hormone) whereas effects of chytrid fungus were limited. ABSTRACT Amphibians have suffered widespread declines caused by many interacting factors whose effects are often difficult to ...
Brian J. Tornabene   +7 more
wiley   +1 more source

A Threshold Effect Analysis of Households' Ability to Maintain Economic Welfare: Rural–Urban Dichotomy in Ghana

open access: yesPolitics &Policy, Volume 53, Issue 5, October 2025.
ABSTRACT This study examines the ability of households to maintain economic welfare and the threshold at which it occurs. We use the Mobile Financial Service Survey (MFSS) data comprising a probability sampling of all Ghanaian households for the econometric analysis.
Alhassan A‐. W. Karakara   +2 more
wiley   +1 more source

东北黑土区农田土壤风蚀的影响因素及其数量关系

open access: yesShuitu Baochi Xuebao, 2017
为明确东北黑土区农田土壤风蚀的主要影响因素,通过室内模拟试验,对比分析了黑土在不同风速(5~14 m/s)、土壤含水量(2%~11%)以及秸秆覆盖率(0~80%)下的风蚀速率差异,进而分析了风蚀速率与各因素之间的数量关系。结果表明,黑土起沙风速略大于5 m/s,其风蚀速率随风速增大呈指数增加,风速14 m/s(含水量2%)时的风蚀速率比8 m/s时增加了11.6~42.7倍。黑土风蚀速率随土壤含水量升高呈先增加后降低趋势;在土壤含水量小于5%时随含水量升高而逐渐增加,至含水量5%时达到峰值并逐渐降低 ...
林, 李和平, 肖
doaj  

芒萁根系对崩岗红土层土壤抗剪强度的影响

open access: yesShuitu Baochi Xuebao, 2020
为探究植物根系对崩岗红土层土壤抗剪强度的作用机制,采取室内直剪试验,研究不同含水率条件下芒萁(Dicranopteris dichotoma)根系对红土层抗剪强度的影响。结果表明:(1)不同根重密度土体的抗剪强度总体随含水率增加而下降,含根土体的抗剪强度大于素土。(2)黏聚力随着含水率的增加均呈先增大后减小的趋势,而随根重密度的增加呈增大的趋势,且增量逐渐减小。(3)内摩擦角与土壤含水率之间呈线性负相关,但与根重密度之间无明显关系。(4)含水率对抗剪强度的影响大于根重密度 ...
林嘉辉   +8 more
doaj  

Reoccurrence of Dust Storms in South Asia and Their Implications for Vegetation Health 南亚沙尘暴的再次出现及其对植被健康的影响

open access: yesIntegrative Conservation, Volume 4, Issue 3, Page 362-380, September 2025.
Occurrences of dust storms and long‐distance movement of dust across landscapes is constantly increasing in south Asia. This dust is expected to have profound impact on vegetation health and sustainability as dust may contribute to nutrient budgets of the forest ecosystems, while it could impart various stresses to the plants.
Shree P. Pandey   +2 more
wiley   +1 more source

初始含水率对崩岗土体抗拉特性的影响

open access: yesShuitu Baochi Xuebao, 2019
针对花岗岩发育的崩岗土体崩壁失稳等问题,通过单轴抗拉试验,研究了湖北通城地区不同初始含水率的崩岗土体抗拉强度特性。结果表明:初始含水率对崩岗土壤抗拉强度影响明显。土壤抗拉强度特征曲线为单峰型,表土层、红土层和红砂过渡层抗拉特征曲线在含水率WC(24.4%)附近出现抗拉强度峰值,而砂土层在WC(25.8%)出现抗拉强度峰值。崩岗不同层次土壤轴向拉伸长和径向收缩长随初始含水率呈现正相关关系,且土壤轴向拉伸率和径向收缩率与初始含水率拟合出相关系数较高的线性函数关系 ...
冯延云   +3 more
doaj  

水分耗散下紫色土埂坎裂隙发育及影响因素

open access: yesShuitu Baochi Xuebao, 2022
埂坎裂隙发育危害埂坎稳定性, 进而影响埂坎水土保持作用的发挥。为揭示失水过程埂坎裂隙发育规律及其主要影响因素, 以紫色土坡耕地埂坎为样地, 采用模拟埂坎试验, 研究不同初始含水率(25%, 30%, 35%)、干密度(1.3, 1.4, 1.5 g/cm3)和加筋量(0.05%, 0.15%, 0.25%)下裂隙发育过程, 通过图像分析方法获取裂隙发育强度和复杂度指标, 分析了裂隙发育与(初始)含水率、干密度、加筋量的关系。结果表明: 水分耗散下裂隙开裂可分为起始阶段、迅速扩展和基本稳定3个阶段 ...
李颖, 韦杰, 罗华进, 甘凤玲
doaj  

Is parvovirus B19 infection upsurge in 2023–2024 associated with adverse pregnancy outcome?

open access: yesUltrasound in Obstetrics &Gynecology, Volume 66, Issue 3, Page 307-313, September 2025.
ABSTRACT Objective A surge in parvovirus B19 infections has been reported in 2023–2024 across Europe and the USA, raising concerns about the associated perinatal risks. The aim of this study was to compare perinatal outcomes following maternal parvovirus B19 infection during the 2023–2024 period with those from a pre‐2023 cohort.
S. Prasad   +22 more
wiley   +1 more source

土壤初始含水率对涌泉根灌土壤水分及氮素运移特性的影响

open access: yesShuitu Baochi Xuebao, 2017
为了探究涌泉根灌水肥一体化灌溉在不同土壤初始含水率下水氮运移特性,通过室内肥液入渗试验,研究了不同土壤初始含水率(4.13%,7.21%,8.77%,11.06%,14.01%)条件下累积入渗量的入渗特性、湿润锋运移、土壤水分以及铵态氮和硝态氮的运移特性,建立了涌泉根灌累积入渗量、各向湿润锋运移距离与不同土壤初始含水率之间的关系,提出了不同初始含水率下涌泉根灌累积入渗量、各向湿润锋运移距离的经验模型。结果表明:累积入渗量、各向湿润锋运移距离以及湿润体内水分和氮素的分布 ...
刘 显   +5 more
doaj  

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