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151.
Snjezana Kovjanic Sebastian C. Schuh Klaus Jonas Niels Van Quaquebeke Rolf van Dick 《组织行为杂志》2012,33(8):1031-1052
Although followers' needs are a central aspect of transformational leadership theory, little is known about their role as mediating mechanisms for this leadership style. The present research thus seeks to integrate and extend theorizing on transformational leadership and self‐determination. In particular, we propose that the satisfaction of followers' basic needs (autonomy, competence, and relatedness) mediates the relationship between transformational leadership and employee outcomes (job satisfaction, self‐efficacy, and commitment to the leader). We tested this model in two studies involving employees from a broad spectrum of organizations in Germany (N = 410) and in Switzerland (N = 442). Results revealed largely consistent patterns across both studies. The need for competence fulfillment solely mediated the link between transformational leadership and occupational self‐efficacy; the need for relatedness fulfillment solely mediated the link between transformational leadership and commitment to the leader. The mediating pattern for the link between transformational leadership and job satisfaction varied slightly across studies. In Study 1, only the need for autonomy fulfillment was a significant mediator, whereas in Study 2, all three needs mediated this relationship. Taken together, our study integrates theorizing on transformational leadership and self‐determination by corroborating that need fulfillment indeed is a central mechanism behind transformational leadership. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
152.
153.
催化荧光法测定痕量亚硝酸根 总被引:12,自引:0,他引:12
本文研究了在稀磷酸介质中,亚硝酸根对溴酸钾氧化中笥红的反应,建立了催化荧光法测定痕量亚硝酸根的方法,实验表明,亚硝酸根在0.05-0.40μg.25ml^-1范围内与ΔF成线性关系,大多数常见的共存离子不影响其测定。本法用于水样中亚硝酸根的测定,结果比较满意。 相似文献
154.
Caste determination in primitively eusocial sweat bees is thought to be due to an interacting suite of factors, including size of the larval provision mass, time of year, and social context of the nest into which a young female emerges. Newly emerged gynes are significantly fatter than newly emerged workers, suggesting the existence of larval caste determination cues. Since photoperiod, temperature, and interactions with nestmates were unlikely to affect larval caste determination, we compared the sizes and contents of larval provision masses destined to produce either workers or gynes. Gyne-destined larvae consumed pollen masses that were larger and contained slightly more sugar than those of worker-destined larvae. We suggest that sugar content is one cue which prompts the development of fat reserves in gyne-destined females but not in worker-destined females. The amount of fat possessed by a newly emerged female influences her chances of successfully entering diapause shortly after emergence. Therefore, small, lean females may be more susceptible to behavioural control by queens and more likely to become workers, while large, fat females would be more likely to become gynes.
Correspondence to: M.H. Richards 相似文献
155.
荔枝花雄蕊和雌蕊发育过程中碳氮化合物的动态变化 总被引:10,自引:0,他引:10
比较分析了荔枝花性决定中碳氮化合物的动态变化。结果发现:C/N较大有利于雄蕊分化,反之则有利于雌蕊分化;氨基酸含量较高有利于雌蕊分化,雄蕊的氨基酸含量仅为雌蕊的一半。脯氨酸与花粉育性存在着密切相关关系。另外,探讨了雌蕊或雄蕊败育的生理意义,在长期的进化中,败育的雌蕊或雄蕊“废物”重新被利用,为同一花中迅速发育的雌蕊或雄蕊提供能量和物质的需求,表5参13。 相似文献
156.
探讨了在MnSO_4-CuSO_4复合催化剂、硫-磷混酸体系中,对样品进行恒温密封消解,用分光光度法测定溶液的COD值。实验得出测定化学需氧量的最佳条件:混酸H_2SO_4-H_3PO_4体积比为4:1,催化剂MnSO_4-CuSO_4质量比为1:2,MnSO_4-CuSO_4的总量为0.03g,消解温度为165℃,消解时间为15min。实验结果表明,此方法的测定结果与重铬酸钾法测定结果的相对误差≤5%,且有较好的重现性及较高的准确度与精密度。本法可同时消解多个试样,适用于大批量试样COD的测定,使试样的消解时间由标准法的2h缩短到了15min,同时用MnSO_4-CuSO_4复合催化剂代替价格昂贵的A_(g2)SO_4,大大降低了分析成本。 相似文献
157.
酸化—吹气—吸收法测定水及废水中的硫化物 总被引:1,自引:0,他引:1
本文设计了硫化物测定的酸化-吹气-吸收装置,验证了装置对硫化的回收效果,对硫化物标准溶液的配制及其稳定性进行了研究,对分析条件进行了最佳选择,建立了亚甲基监光度法测定硫化物的分析方法,并对实际样品进行了测定。本方法的检出限为0.005mgS^2-/l,线性范围为0.005-0.700mgS^2-/l,可应用于水和废水样品中微量硫化物的测定。 相似文献
158.
Andra Thiel Gerard Driessen Thomas S. Hoffmeister 《Behavioral ecology and sociobiology》2006,59(5):614-623
The parasitic wasp, Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae), has two reproductive modes, namely, thelytoky or arrhenotoky, and occurs in habitats
with highly variable or relatively stable host abundances, respectively. Since information processing is costly, we expected
that information indicating resource availability would be mainly used by the thelytokous wasps and less so by the arrhenotokous
type. This idea was explored by two different approaches. In a study on patch-time allocation, we used females from ten populations
and measured patch-residence times of individuals that visited multiple patches at different encounter rates. In a more detailed
approach, thelytokous and arrhenotokous females from a single location were observed continuously while foraging, and all
behaviors were recorded. Wasps of both reproductive modes (i.e., both habitat types) used information for the assessment of
habitat quality. However, the way that the information was used differed between them. Whereas thelytokous females used foraging
information to maximize their efficiency at high patch-encounter rates, arrhenotokous females merely reduced the number of
offspring produced without changing patch times. The behavior of the arrhenotokous females should result in a spreading of
offspring across the habitat and, thus, reduced sib-mating. The foraging strategy of these wasps might therefore be an adaptation
to reduce costs associated with inbreeding. 相似文献
159.
极值理论是概率论中的一个分支,在许多领域已被广泛应用。本文用历史地震资料对江苏及邻区作大震级范围的极值理论分析,用近几十年来的小震资料分别对苏北地区和苏南地区进行了较小震级范围的极值理论分析,对未来按不同的年份进行了缺震估计,并对1995年9月20日的苍山5.2级地震、1996年11月9日的南黄海6.1级地震作了内符检验。 相似文献
160.
近十年水中硫化物测定方法的进展 总被引:3,自引:0,他引:3
评述了1985~1996年间报道的水中硫化物方法概况,内容包括:水样的预处理方法,水样测定的分光光度法,电化学法,原子吸收光谱以及其他分析方法等。 相似文献