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441.
Vedder O Magrath MJ Niehoff DL van der Velde M Komdeur J 《Behavioral ecology and sociobiology》2012,66(4):603-612
Although functional explanations for female engagement in extra-pair copulation have been studied extensively in birds, little
is known about how extra-pair paternity is linked to other fundamental aspects of avian reproduction. However, recent studies
indicate that the occurrence of extra-pair offspring may generally decline with laying order, possibly because stimulation
by eggs induces incubation, which may suppress female motivation to acquire extra-pair paternity. Here we tested whether experimental
inhibition of incubation during the laying phase, induced by the temporary removal of eggs, resulted in increased extra-pair
paternity, in concert with a later cessation of laying, in blue tits (Cyanistes caeruleus). As expected, experimental females showed a more gradual increase in nocturnal incubation duration over the laying phase
and produced larger clutches than controls. Moreover, incubation duration on the night after the first egg was laid predicted
how extra-pair paternity declined with laying order, with less incubation being associated with more extra-pair offspring
among the earliest eggs in the clutch. However, incubation duration on this first night was unrelated to our experimental
treatment and independent of final clutch size. Consequently, the observed decline in extra-pair paternity with laying order
was unaffected by our manipulation and larger clutches included proportionally fewer extra-pair offspring. We suggest that
female physiological state prior to laying, associated with incubation at the onset of laying, determines motivation to acquire
extra-pair paternity independent of final clutch size. This decline in proportion of extra-pair offspring with clutch size
may be a general pattern within bird species. 相似文献
442.
Two studies were conducted to address the potential nonlinear relationship between emotional exhaustion and voice. Study 1 developed and tested a model rooted in conservation of resources theory in which responses to emotional exhaustion are determined by individual‐level and group‐level conditions that influence the perceived safety and efficacy of voice and drive prohibitive voice behaviors by giving rise to either resource‐conservation‐based or resource‐acquisition‐based motivation. Specifically, there was a curvilinear (U‐shaped) relationship between emotional exhaustion and prohibitive voice under conditions of (i) high job security and (ii) high interactional justice climate, but a linearly negative relationship when these resources were low. Study 2 replicated and extended these findings to include an empirical examination of these effects on promotive versus prohibitive voice. Results confirmed the findings of Study 1, provided evidence of differences in the nomological networks of promotive and prohibitive voice, and indicated that prohibitive voice is more salient to the experience of high emotional strain. Implications of the findings and areas for future research are discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
443.
Climate change influences populations by reducing or extirpating local populations, by disrupting patterns of migration and by shifting geographical distributions. These events can affect genetic population structure in several ways. Molecular markers have been used in numerous population genetic and phylogeographical studies of marine species and have detected population responses to climate change in the last few decades, such as range expansions, adaptative shifts and declines or increases in abundance. Little is known, however, about the molecular and physiological basis of adaptive responses to climate change in marine Mediterranean species. The Mediterranean Sea ecosystem is a ‘living laboratory’ with native species that are challenged by environmental change and by invasive species and a ‘gene-climate’ approach should be adopted as a way of focusing on the relationship between climate warming and genetic diversity. 相似文献
444.
Patrizia Jereb Rita Cannas Porzia Maiorano Giambattista Bello Fulvio Garibaldi Marco Mereu Francesco G. Ancona Giovanni Ammendolia Pietro Battaglia Önder Duysak Hendrik Jan T. Hoving Eugenia Lefkaditou Marek R. Lipinski Riccardo Melis Panagiota N. Peristeraki Sergio Ragonese Teresa Romeo Alp Salman Maria Begoña Santos Alberto Villari Danila Cuccu 《Marine Biology》2016,163(11):229
445.
Luisa Barbieri Roberto Giovanardi Isabella Lancellotti Marco Michelazzi 《Environmental Chemistry Letters》2010,8(2):171-178
A new method for the recovery of precious metals, in particular gold, from electronic waste is proposed. This work focused
on the research of an easily renewable etching agent, in order to make an environmentally friendly process possible. Two well
known hydrometallurgical etching agents, FeCl3 and CuCl2, were evaluated in terms of efficiency and kinetics, testing solutions with different concentration of etchant and hydrochloric
acid. The recovery of spent etching solutions was evaluated: promising results were found in the case of CuCl2, which can be completely restored by oxidation of the cuprous chloride formed during the etching using atmospheric oxygen. 相似文献
446.
A mobile sampling and measurement system for the analysis of gaseous and liquid samples in the field was developed. An inductively coupled plasma optical emission spectrometer (ICP-OES), which is built into a van, was used as detector. The analytical system was calibrated with liquid and/or gaseous standards. It was shown that identical mass flows of either gaseous or liquid standards resulted in identical ICP-OES signal intensities. In a field measurement campaign trace and minor elements in the raw flue gas of a waste wood combustor were monitored. Sampling was performed with a highly transport efficient liquid quench system, which allowed to observe temporal variations in the elemental process gas composition. After a change in feedstock an immediate change of the element concentrations in the flue gas was detected. A comparison of the average element concentrations during the combustion of the two feedstocks showed a high reproducibility for matrix elements that are expected to be present in similar concentrations. On the other hand elements that showed strong differences in their concentration in the feedstock were also represented by a higher concentration in the flue gas. Following the temporal variations of different elements revealed strong correlations between a number of elements, such as chlorine with sodium, potassium and zinc, as well as arsenic with lead, and calcium with strontium. 相似文献
447.
L. Sola S. De Innocentiis E. Gornung S. Papalia A. R. Rossi G. Marino P. De Marco S. Cataudella 《Marine Biology》2000,137(1):47-51
A cytogenetic analysis was carried out on specimens of Epinephelus marginatus (Lowe, 1834) from three localities in the Mediterranean Sea, to deepen knowledge of the chromosome complement of the species
and identify any possible population-specific cytogenetic markers. All specimens had a 2n = 48 acrocentric karyotype with two Ag-, chromomycin A3- and C-positive NORs (nucleolar organizer regions) in the subcentromeric region of the smallest chromosome pair. The constitutive
heterochromatin was distributed centromerically. Except for NORs, neither eu- nor heterochromatin show fluorescence after
fluorochrome staining, i.e. there is no localized increase of AT- or GC-rich DNA. In all populations, the (TTAGGG)
n
telomeric sequences are restricted to the telomeres, and the 18S and the 5S rDNA clusters are located on different chromosome
pairs. In specimens from Sardinia, additional signals after C-banding, Ag-staining and FISH (fluorescence in situ hybridization)
with 18S rDNA can be observed in the telomeric region of one or two large-sized chromosomes, classified as No. 2. This suggests
that additional and variable NORs could be detected in the species in addition to those on the genus-specific, NOR-bearing
Chromosome Pair 24.
Received: 20 October 1999 / Accepted: 14 April 2000 相似文献
448.
449.
Pastorino Paolo Pizzul Elisabetta Bertoli Marco Perilli Selene Brizio Paola Salvi Gianguido Esposito Giuseppe Abete Maria Cesarina Prearo Marino Squadrone Stefania 《Environmental science and pollution research international》2020,27(6):5958-5970
Environmental Science and Pollution Research - Alpine lakes are extreme ecosystems located in remote areas and populated by few but well-adapted species. Because of their remote location, they are... 相似文献
450.
Alessandra De Bruno Rosa Romeo Francesca L. Fedele Andrea Sicari Amalia Piscopo Marco Poiana 《Journal of environmental science and health. Part. B》2018,53(8):526-533
In this study, the effects of experimental variables such as type of solvent, sample/solvent ratio, and time of extraction have been evaluated to individuate the best results in phenolic recovery by Olive Pomaces (OP) belonging to Carolea and Ottobratica cultivars. Folin–Ciocaulteu procedure and DPPH and ABTS assays were used, respectively, for total phenol quantification and total antioxidant activity of pomace extracts. The ethanol/water mixture was resulted the most efficient extraction solvent for both olive cultivars. The highest amount of phenolic compounds (171 ± 4 mg of gallic acid 100 g?1 of dry pomace) was obtained after extraction at 120 min with 2:1 solvent/OP (v/w) of Ottobratica Olive Pomace. The recovery of phenol compounds from olive wastes increases the sustainability of sector, allowing obtaining an extract that could be a suitable alternative in the food industry to the use of synthetic antioxidants in order to improve the quality of foods. 相似文献