Results 71 to 80 of about 27,177 (219)
How New Issues Become Polarized: Partisan Triggers and Subsystem Shopping in Early AI Policymaking
Policy &Internet, Volume 18, Issue 1, March 2026.ABSTRACT Early AI policymaking in the United States appeared bipartisan, but subsequent developments raise the question of whether AI policy will become more polarized over time. To examine how partisanship takes root around novel policy issues, we perform a mixed‐methods study, analyzing survey data from 129 state legislators in 44 states and ...
Robin Jacobson +2 more
wiley +1 more source
Shuitu Baochi Xuebao, 2005 采用室内分根营养液培养及PEG模拟水分胁迫的方法,研究不同氮素形态(NH4 -N、NO3--N、NH4 -N/NO3--N比为50/50)对水稻局部根系遭遇水分胁迫后的生物学响应状况。结果表明,在非水分胁迫的条件下,供应NO3--N营养相对促进分蘖期水稻的根系发育,而供应NH4 -N营养相对促进分蘖期水稻的地上部发育;在局部根系受到水分胁迫的条件下,NH4 -N和NO3--N混合营养水稻生物量增量分别比全NO3--N和全NH4 -N营养水稻高31.7%和37.7%,其中地上部生物量增量也分别比全NO3--
周毅 郭世伟 沈其荣
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The power of ionic movements in plants
New Phytologist, Volume 249, Issue 5, Page 2232-2240, March 2026.Summary The movement of ion‐driven electrogenic events known as plant action potentials in the Venus flytrap Dionaea muscipula has first been recognized in Darwin's time. Besides electrophysiological techniques making use of current‐ and voltage‐recording electrodes, today an ever‐growing spectrum of tools has become available, that report online ...
Rainer Hedrich, Ines Kreuzer
wiley +1 more source
New Phytologist, Volume 249, Issue 5, Page 2452-2466, March 2026.Summary Plants orchestrate their developmental processes and responses to environmental stimuli through a sophisticated network of small signaling molecules, termed phytohormones. Among these, auxins are recognized for their role in promoting plant growth.
José Moya‐Cuevas +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2007 用全挖取样法研究了干旱荒漠区不同类型沙地上沙蒿种群的根系生态特征。结果表明,沙蒿根系总生物量在不同类型沙地上有所变化,其排序为流动沙地（122.43 g）〉封育沙地（106.35g）〉半固定沙地（90.15 g）;从根系分布深度看,在不同类型沙地上,沙蒿根系生物量集中分布在0-40cm土层中,占75%以上;沙蒿的主根生物量在0-20cm土层中最多,其根系生物量占全部根系生物量的比例在封育沙地为67.11%,流动沙地为53.52%,半固定沙地为62.48%;侧根生物量在封育沙地和半固定沙地中在0 ...
王辉 +4 more
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Shuitu Baochi Xuebao, 2022 通过模拟试验,研究启动磷肥施用在土壤中不同位置对滴灌玉米苗期生长、根系形态发育以及根系与土壤磷养分空间分布的影响,为明确启动磷肥最佳施肥位置及其对滴灌玉米苗期生长的影响提供理论依据。利用根箱设置启动磷肥:(1)模拟滴灌施肥(T1);(2)种子侧方5 cm、下方5 cm穴施(T2);(3)种子侧方5 cm、下方12 cm穴施(T3);(4)不施启动磷肥(CK)4个处理,根据大田启动磷肥施用量(P2O5 30 kg/hm2)设置启动磷肥用量为P2O5 0.2 g/kg土。分析各处理对玉米苗期生长、根系构型 ...
冯国瑞 +6 more
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, 2017 独脚金内酯是独脚金醇类化合物的总称,是一种倍半萜内酯,来源自类胡萝卜素生物合成途径。近年来研 究发现,独脚金内酯不仅具有刺激种子发芽,还具有诱导丛枝菌根真菌分支和抑制植物分枝等多重生物学功能。独脚金内酯的多重角色在植物自身发育与周围环境的协调过程中发挥着重要作用。为了深入了解独脚金内酯,笔者归纳了其所具有的多重“角色”:种子萌发刺激物,共生信号物质及新型植物激素,并进一步探讨了各种功能与其结构的内在关系 ...
任承钢 孔存翠 王计平 李润植 解志红 +1 more
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Climate adaptation and functional constraints drive pollen evolution in Apiales
New Phytologist, Volume 249, Issue 5, Page 2574-2587, March 2026.Summary Pollen grains exhibit remarkable morphological diversity, shaped by selective pressures from environmental factors and mechanical constraints. Here, we investigate macroevolutionary patterns of pollen morphology in Apiales, an order of angiosperms with significant ecological and geographical diversity, to disentangle the roles of climate and ...
Jakub Baczyński +3 more
wiley +1 more source
Shuitu Baochi Xuebao, 2019 采用原状土冲刷水槽法，以油松林、刺槐林、山杏林、荆条地及荒草地土壤为研究对象，研究了晋西黄土残塬沟壑区蔡家川流域不同植被类型土壤抗冲性能及植物根系对土壤抗冲性的影响。结果表明：（1）在原状土冲刷试验过程中，各植被类型径流量随冲刷时间的变化趋势不明显，含沙量随时间延长先减少后趋于平稳，土壤抗冲指数呈逐渐增加的趋势。（2）各植被类型总根长密度、根表面积密度、根体积密度及根生物量密度均表现为刺槐、油松林地较大，山杏、荆条、荒草地较小且相差不大，总根系参数之间均存在正相关关系。各植被类型不同根径范围（0~0.5，
金晓, 陈丽华
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Shuitu Baochi Xuebao, 2022 以昭通烂泥箐滑坡源区优势物种鸢尾科鸢尾属鸢尾原生根系—土复合体作为研究对象，采用直剪试验对复合体抗剪特征进行深入研究，并与室内相同含水率重塑复合体试验结果对比分析。结果表明，整体上无根素土具有应变软化特征，而复合体具有应变硬化的特性，各复合体的抗剪强度均比素土的高，且抗剪强度随着含根量的增加而增加，根系加固效应明显，但复合体并没出现与重塑土类似的最优（最佳）含根量。原状复合体的c值随含根量的增加没有明显变化规律，而φ值则逐渐递增，其增长率也有相同的变化趋势。复合体破坏断面显示根系为主根系且垂直贯通剪切面，
徐宗恒 +4 more
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