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Rare royal families in honeybees, Apis mellifera   总被引:1,自引:0,他引:1  
The queen is the dominant female in the honeybee colony, Apis mellifera, and controls reproduction. Queen larvae are selected by the workers and are fed a special diet (royal jelly), which determines caste. Because queens mate with many males a large number of subfamilies coexist in the colony. As a consequence, there is a considerable potential for conflict among the subfamilies over queen rearing. Here we show that honeybee queens are not reared at random but are preferentially reared from rare “royal” subfamilies, which have extremely low frequencies in the colony's worker force but a high frequency in the queens reared.  相似文献   
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A fundamentalistic point of view is for the evaluation of genetic engineering inadequate. Using ethics to evaluate the consequences is not valid for gene transfers across species as a morally relevant criterion but is rather the assessment of toxic, pathogenic, and ecological effects of transgenic organisms. A criterion for human genetics is not the inviolability of the human embryo, but social and human tolerance and the consent of the affected.  相似文献   
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A Wolf  K Bunzl  F Dietl  W.F Schmidt 《Chemosphere》1977,6(5):207-213
Distribution coefficients for the sorption of Pb2+, Cu2+, Cd2+ and Zn2+ by peat were determined as a function of the Ca2+-content of peat as well as of the Ca2+-concentration in the solution. The amount of heavy metal ions taken up was measured for Cu2+, Cd2+ and Zn2+ by atomic absorption spectrometry and for Pb2+ by using Pb-212 as a radioactive tracer.The results show that the distribution coefficients of the heavy metal ions increase, if one increases the initial ratio of the Ca2+H+-ions in the peat phase. The distribution coefficients for the heavy metal ions decrease, however, if - at constant initial Ca2+-content of the peat - the Ca2+-concentration of the solution is increased.  相似文献   
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A comparison between predicted and observed odor intensities at 20 neighborhood residences in the vicinity of seven various livestock farms in five different Minnesota counties was made to evaluate the Odor From Feedlots, Setback Estimation Tool (OFFSET) developed by the University of Minnesota. Observations by neighborhood monitors suggest that the OFFSET-predicted separation distances for annoyance-free frequencies of 99, 98, and 97% are large enough. The observations additionally indicate that predicted distances to obtain 94 and 91% annoyance-free frequencies may be large enough for some farms, but for other farms, greater distances may be needed. For two farms in the study, no significant difference between all of the observed and predicted intensities could be found. At four sites, a significant difference was found, and at three of these the difference was considerable. Odor emission rates used in the OFFSET model seem to describe the average emission fairly well for many odor sources, but improvement may be needed for some types of sources. Possible reasons for observations of annoying odor when not predicted include fluctuations in the odor emissions, wind speed fluctuations, topographic variation between sites, sensitivity differences by neighborhood monitors, and background emissions from other sources.  相似文献   
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This paper presents a digitized version of a thermodynamic sorption database, implemented as a relational database with MS Access. It is mineral-specific and can therefore be used for additive models of complex solid phases such as rocks or soils. An integrated user interface helps users to access selected mineral and sorption data, to extract internally consistent data sets for sorption modeling, and to export them in formats suitable for other modeling software. Data records comprise mineral properties, specific surface area values, surface binding sites' characteristics, sorption ligand information, and surface complexation reactions. An extensive bibliography is included, providing links not only to the above listed data, but also to background information concerning surface complexation model theories, evidence for surface species, and sorption experimental techniques.  相似文献   
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