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161.
162.
Johannes Methfessel 《Die Naturwissenschaften》1957,44(11):329-329
163.
164.
Tobias Weil Katharina Hoffmann Johannes Kroiss Erhard Strohm Judith Korb 《Die Naturwissenschaften》2009,96(2):315-319
In social insects, it is assumed that signals of the queen inform nestmates about her reproductive status. Thus, workers forego
their own reproduction if the queen signals high fertility. In hemimetabolous termites, little is known about reproductive
inhibition, but evidence exists for a royal-pair control. Workers of lower termites exhibit a high developmental flexibility
and are potentially able to become reproductives, but the presence of a fertile reproductive restrains them from reaching
sexual maturity. The nature of this control, however, remains unknown. Here, we report on qualitative differences in cuticular
hydrocarbon profiles between queens and workers of the basal drywood termite Cryptotermes secundus. Queens were characterized by a shift to long-chained and branched hydrocarbons. Most remarkably, similar chemical patterns
are regarded as fertility cues of reproductives in social Hymenoptera. This might suggest that both groups of social insects
convergently evolved similar chemical signatures. The present study provides deeper insights into how termites might have
socially exploited these signatures from sexual communication in their cockroach-like ancestor.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
165.
166.
Oxidation of As(Ⅲ) by potassium permanganate 总被引:3,自引:1,他引:2
LI N FAN Maohong Van Leeuwen Johannes Saha Basude YANG Hongqun HUANG C. P. 《环境科学学报(英文版)》2007,19(7):783-786
The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effective agent for oxidation of As(Ⅲ) in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As(Ⅲ) by Mn(Ⅲ). Although theoretical redox analyses suggest that Mn(Ⅶ) should have better performance in oxidization of As(Ⅲ) within lower pH ranges, the experimental results show that the oxidation efficiencies of As(Ⅲ) under basic and acidic conditions were similar, which may be due to the adsorption of As(Ⅲ) on the Mn(OH)2 and MnO2 resulting from the oxidation of As(Ⅲ). 相似文献
167.
Bernd Klauer Johannes Schiller Frauke Bathe 《Journal of Environmental Planning and Management》2015,58(11):1944-1960
The EU Water Framework Directive calls for cost effective measures to achieve a “good status” in all European ground, surface and coastal waters. Besides eutrophication, the degradation of hydromorphology is the main reason for failing this objective. In this paper, we conceptualise the interactive decision support process BASINFORM-M for finding proper locations for river restoration. The concept combines the recently proposed “stepping stone approach” from aquatic ecology with elements from cost effectiveness analysis, multi-criteria analysis and participatory approaches. BASINFORM-M exemplifies a shift away from the isolated restoration of single river reaches towards a consideration of functional relationships within river networks. 相似文献
168.
Kennedy Marc C. Garthwaite David G. de Boer Waldo J. Kruisselbrink Johannes W. 《Environmental science and pollution research international》2019,26(10):9892-9907
Environmental Science and Pollution Research - Human exposure to pesticide mixtures can occur from the diet and other sources. Realistic exposure and risk assessments should include multiple... 相似文献
169.
Who gets the benefit of the doubt? The impact of causal reasoning depth on how violations of gender stereotypes are evaluated
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A large body of research demonstrates that women encounter severe penalties for violating gender stereotypes. In this paper, we explore the conditions under which the reverse is true—when being subject to a stereotype can actually benefit a woman compared to a man who is not subject to the same stereotype. In particular, we suggest that in situations of causal ambiguity—uncertainty about the reasons that a behavior occurred—differences in how men and women are evaluated will be moderated by the extent to which observers engage in a low or a high level of deliberative causal reasoning. In 3 experimental studies, participants were asked to make judgments about an employee who violated a female gender stereotype by failing to provide help to a coworker when asked to do so, but the reasons for this behavior were unclear. When participants were prompted to engage in deliberative causal reasoning, women were evaluated more positively than men, but not in the absence of such a prompt. Moreover, when participants did engage in deliberative causal reasoning, the more positive evaluations of women compared to men were driven by participants' beliefs that women's behavior was due more to situational constraints than the same behavior by men. 相似文献
170.
Volker Matthias Jan A. Arndt Armin Aulinger Johannes Bieser Hugo Denier van der Gon Richard Kranenburg 《Journal of the Air & Waste Management Association (1995)》2018,68(8):763-800
Poor air quality is still a threat for human health in many parts of the world. In order to assess measures for emission reductions and improved air quality, three-dimensional atmospheric chemistry transport modeling systems are used in numerous research institutions and public authorities. These models need accurate emission data in appropriate spatial and temporal resolution as input. This paper reviews the most widely used emission inventories on global and regional scales and looks into the methods used to make the inventory data model ready. Shortcomings of using standard temporal profiles for each emission sector are discussed, and new methods to improve the spatiotemporal distribution of the emissions are presented. These methods are often neither top-down nor bottom-up approaches but can be seen as hybrid methods that use detailed information about the emission process to derive spatially varying temporal emission profiles. These profiles are subsequently used to distribute bulk emissions such as national totals on appropriate grids. The wide area of natural emissions is also summarized, and the calculation methods are described. Almost all types of natural emissions depend on meteorological information, which is why they are highly variable in time and space and frequently calculated within the chemistry transport models themselves. The paper closes with an outlook for new ways to improve model ready emission data, for example, by using external databases about road traffic flow or satellite data to determine actual land use or leaf area. In a world where emission patterns change rapidly, it seems appropriate to use new types of statistical and observational data to create detailed emission data sets and keep emission inventories up-to-date.
Implications: Emission data are probably the most important input for chemistry transport model (CTM) systems. They need to be provided in high spatial and temporal resolution and on a grid that is in agreement with the CTM grid. Simple methods to distribute the emissions in time and space need to be replaced by sophisticated emission models in order to improve the CTM results. New methods, e.g., for ammonia emissions, provide grid cell–dependent temporal profiles. In the future, large data fields from traffic observations or satellite observations could be used for more detailed emission data. 相似文献