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Madeleine Beekman Stephen J. Martin Falko Drijfhout Benjamin P. Oldroyd 《Behavioral ecology and sociobiology》2007,61(12):1847-1853
Anarchy, where honeybee workers produce males in the presence of a queen, is extremely rare in natural honeybee populations,
suggesting that there are colony-level costs associated with being anarchistic. Yet, no significant costs have yet been identified.
A possible reason for this may be that researchers have only focused on the behaviour of anarchistic workers, which have been
shown to perform worker-tasks as do wild-type workers. Possibly, therefore, costs associated with anarchy should be sought
in anarchistic queens and not workers. A potential cost could be a lower survival rate of eggs laid by anarchistic queens
perhaps because their egg-marking signal is not as clear as that of a wild-type queen. In this paper, we determined the removal
rate of eggs laid by anarchistic queens in standard worker-policing bioassays. Our results show that eggs laid by anarchistic
queens are removed at a higher rate than eggs laid by wild-type queens. This does not seem to be due to differences in hydrocarbons
found on the surface of eggs, as both egg types showed the same alkanes and alkenes in similar proportions. We postulate that
higher removal rates of queen-laid eggs due to recognition errors may be one reason that anarchy is rare in natural honeybee
populations. 相似文献
225.
Angie C. Jelin Katelynn G. Sagaser Katherine R. Forster Tochi Ibekwe Mary E. Norton Eric B. Jelin 《黑龙江环境通报》2020,40(5):528-537
Early pregnancy renal anhydramios (EPRA) comprises congenital renal disease that results in fetal anhydramnios by 22 weeks of gestation. It occurs in over 1 in 2000 pregnancies and affects 1500 families in the US annually. EPRA was historically considered universally fatal due to associated pulmonary hypoplasia and neonatal respiratory failure. There are several etiologies of fetal renal failure that result in EPRA including bilateral renal agenesis, cystic kidney disease, and lower urinary tract obstruction. Appropriate sonographic evaluation is required to arrive at the appropriate urogenital diagnosis and to identify additional anomalies that allude to a specific genetic diagnosis. Genetic evaluation variably includes karyotype, microarray, targeted gene testing, panels, or whole exome sequencing depending on presentation. Patients receiving a fetal diagnosis of EPRA should be offered management options of pregnancy termination or perinatal palliative care, with the option of serial amnioinfusion therapy offered on a research basis. Preliminary data from case reports demonstrate an association between serial amnioinfusion therapy and short-term postnatal survival of EPRA, with excellent respiratory function in the neonatal period. A multicenter trial, the renal anhydramnios fetal therapy (RAFT) trial, is underway. We sought to review the initial diagnosis ultrasound findings, genetic etiologies, and current management options for EPRA. 相似文献
226.
Lawrence Martin 《Journal of Cleaner Production》2010,18(10-11):1122-1123
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Martin J. Atkins Michael R.W. Walmsley James R. Neale 《Journal of Cleaner Production》2010,18(9):927-934
The integration of non-continuous processes such as a milk powder plant presents a challenge for existing process integration techniques. Current techniques are generally based on steady and continuous operation which for some industries is not the case. Milk production varies considerably during the year as dairy cows in New Zealand are grazed on pasture. In this paper the potential for indirect heat transfer between the several plants using a heat recovery loop and stratified tank at a typical New Zealand dairy factory is investigated. The maximum amount of heat recovery is calculated for a range of recirculation loop temperatures. The maximum amount of heat recovery can be increased considerably if the temperature of the hot fluid in the recirculation loop is varied depending on which condition the site is operating under. 相似文献
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This paper sets out a few results of research on waste prevention, recycling and disposal in The Netherlands. First, an outline is given of the actual waste disposal. Secondly, a projection is made of the different waste categories as a result of independent developments for the year 2000. Finally, a scenario is presented in which recent Dutch policy on the prevention and recycling of waste, as well as incineration, play important roles. The waste policy will be based on the long-term objective of sustainable development, as mentioned in the Brundtland Commission report. Results are given concerning space, costs and emissions. 相似文献
230.
Bradley S. Jorgensen John F. Martin 《Journal of Environmental Planning and Management》2015,58(3):513-536
Australian governments have sought to invest in irrigation infrastructure to improve the efficiency of water delivery to rural properties and improve water supply and on-farm efficiency. A programme of rationalising irrigation infrastructure has attracted criticism and doubts about its likely success. Attitude theory in the form of the Reasoned Action Model was applied to understand the intentions of landowners to connect to a ‘modernised’ irrigation system. Attitudes towards connecting to the system, social norms and perceptions of control over the behaviour provided an explanation of intentions to connect. Actual financial capability and other variables were important in discriminating a group of landowners who had already connected to the modernised system from farmers who had not. 相似文献