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101.
Maternal yolk androgens in bird eggs represent an important pathway along which offspring phenotype is shaped. Most of the hormone-mediated maternal effects are highly important in the context of sibling competition. However, there is also increasing evidence for long-lasting effects far beyond the nestling period, and these effects may have important consequences on the reproductive success of the offspring. Here, we investigated the effects of experimentally elevated yolk testosterone concentrations on growth and reproduction in female canaries. Elevated yolk testosterone concentrations enhanced the post-natal growth rate, but not the asymptotic mass, and reduced the survival probability. The latter may be a consequence of the higher growth rate, which may have rendered females hatching from testosterone-treated eggs (T-females) more vulnerable to harsh environmental conditions. Adult T-females made a larger investment in their clutch by laying more but not heavier eggs than females hatching from control-treated eggs. Our results suggest that the observed long-lasting effect on clutch size relates to changes in the growth trajectory rather than being a direct consequence of testosterone, since studies manipulating early growth conditions obtained similar results. Clearly, further studies are now required in order to investigate the intriguing relationship between yolk testosterone, elevated growth rates, and clutch size.  相似文献   
102.
An increased focus on renewable energy has led to the planning and construction of marine wind farms in Europe. Since several terrestrial studies indicate that raptors are especially susceptible to wind turbine related mortality, a Spatial Planning Tool is needed so that wind farms can be sited, in an optimal way, to minimize risk of collisions. Here we use measurements of body mass, wingspan and wing area of eight European raptor species, to calculate their Best Glide Ratio (BGR). The BGR was used to construct a linear equation, which, by the use of initial take-off altitude, could be used to calculate a Theoretical Maximum Distance (TMD) from the coast, attained by these soaring-gliding raptor species. If the nearest turbine, of future marine wind farms, is placed farther away from the coast than the estimated TMD, the collision risk between the turbine blades and these gliding raptors will be minimized. The tool was demonstrated in a case study at the Rødsand II wind farm in Denmark. Data on raptor migration altitude were gathered by radar. From the TMD attained by registered soaring-gliding raptors in the area, we concluded that the Rødsand II wind farm is not sited ideally, from an ornithological point of view, as potentially all three registered species are at risk of gliding through the area swept by the turbine rotor blades, and thereby at risk of colliding with the wind turbines.  相似文献   
103.
Journal of Material Cycles and Waste Management - The chemical characterization of the food waste allowed to discriminate between the pre-preparation and post-preparation residues from a...  相似文献   
104.
In presenting examples from the most extensive and demanding fire in modern Swedish history, this paper describes challenges facing hastily formed networks in exceptional situations. Two concepts that have been used in the analysis of the socio‐technical systems that make up a response are conversation space and sensemaking. This paper argues that a framework designed to promote understanding of the sensemaking process must take into consideration the time and the location at which an individual is engaged in an event. In hastily formed networks, location is partly mediated through physical systems that form conversation spaces of players and their interaction practices. This paper identifies and discusses four challenges to the formation of shared conversation spaces. It is based on the case study of the 2006 Bodträskfors forest fire in Sweden and draws on the experiences of organised volunteers and firefighters who participated in a hastily formed network created to combat the fire.  相似文献   
105.
The aim of this work was to evaluate the use of Monte Carlo-based calibrations for in situ gamma-ray spectrometry. We have performed in situ measurements at five different sites in Sweden using HPGe detectors to determine ground deposition activity levels of 137Cs from the 1986 Chernobyl accident. Monte Carlo-calculated efficiency calibration factors were compared with corresponding values calculated using a more traditional semi-empirical method. In addition, results for the activity ground deposition were also compared with activity densities found in soil samples. In order to facilitate meaningful comparisons between the different types of results, the combined standard uncertainty of in situ measurements was assessed for both calibration methods. Good agreement, both between the two calibration methods, and between in situ measurements and soil samples, was found at all five sites. Uncertainties in in situ measurements for the given measurement conditions, about 20 years after the fallout occurred, were found to be in the range 15–20% (with a coverage factor k = 1, i.e. with a confidence interval of about 68%).  相似文献   
106.
The goal of this study was to optimize the mixture of swine manure (SM) and cattle manure (CM) used in the vermicomposting process, seeking to increase the manure biodegradation rate and enhance the biomass production of both earthworms and higher plants. To achieve this goal, physico-chemical parameters were determined to assess the final compost quality after 50 days of vermicomposting. The different manure ratios used to produce the composts (C) were as follows (SM:CM, % m/m basis): C1 100:0, C2 (75:25), C3 (50:50), C4 (25:75), and C5 (0:100). In addition, the earthworm biomass and the phytoproductivity of lettuce (Lactuca sativa L.) plants grown in mixtures (1:1) of natural soil and the most viable vermicomposts were investigated. The C1 and C2 compost compositions were associated with high earthworm mortality rates. The C3 compost provided the highest mineral concentrations and C5 showed the highest lettuce yield (wet biomass). The results verify that stabilized cattle manure is an excellent substrate for the vermicomposting process and that fresh swine manure must be mixed with pre-stabilized cattle manure to ensure an optimized vermicomposting process, which must be controlled in terms of temperature and ammonia levels. It is concluded that small livestock farmers could add value to swine manure by applying the vermicomposting process, without the need for high investments and with a minimal requirement for management of the biodegradation process. These are important technical aspects to be considered when circular economy principles are applied to small farms.  相似文献   
107.
Environmental Science and Pollution Research - A field experiment with thin-layer capping was conducted in the Grenland fjords, Norway, for remediation in situ of mercury and dioxin-contaminated...  相似文献   
108.
Ambio - The Circumpolar Biodiversity Monitoring Programme (CBMP) provides an opportunity to improve our knowledge of Arctic arthropod diversity, but initial baseline studies are required to...  相似文献   
109.
The effectiveness of different conservation policies is debated, but the policies are rarely evaluated quantitatively. A voluntary or 'soft' policy based mainly on education provides information about ecosystems and effects of land use, to encourage conservation action. Swedish forestry relies mainly on soft policy, with substantial resources for education and advice to more than 200,000 forest owners, while legal regulation is weak. Increased retention of broadleaved trees at clear-cutting, with environmental benefits in the conifer-dominated forestry, is important in the policy. We used the Swedish National Forest Inventory to analyse this policy for young forests in southern Sweden. Between 1983-1987 and 1998-2002 the policy had no positive effect on saplings (1.3m tall to 4.9 cm dbh) of birch, oak, beech and other species that mostly decreased in density, due to planting of conifers and browsing by ungulates. However, broadleaved conservation trees (>or=15 cm dbh) increased in density, e.g. to about one oak and six birches per ha in young coniferous forest in 1998-2002. The relative increase in density was higher for large (>or=20 cm dbh) than for small trees (15-20 cm dbh). The density of conservation trees was higher on forestland of high than of low productivity. Thus, the soft conservation policy did not influence regeneration of saplings in this type of forestry system, but large broadleaved trees were increasingly saved at 'clear-cuttings'. Advice and educational programmes probably contributed to this result. A continued increase in conservation trees at harvest may require economical support to forest owners.  相似文献   
110.
The aim of the present study was to estimate spillover effects between the work and the family sphere in a sample of nurses (N = 2058). Hierarchical regression analyses investigated whether shift work schedules were associated with negative or positive spillover, both from family to work and vice versa, controlling for demographic factors, job demands and decision latitude. With daytime work as a reference group, all types of shift work (day and evening shift, night shift only and rotating 3 shift) were associated with higher negative work-to-family spillover. Night work was associated with significantly less negative family-to-work spillover. None of the different shift work schedules were related to any type of positive spillover. The results indicate that working outside of daytime hours is less compatible with workers’ family lives, compared to working ordinary day shifts. On the other hand, working night shifts only was associated with reduced negative family-to-work spillover.  相似文献   
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