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The European Common Agricultural Policy still follows its primary goals, i.e. quality food at affordable prices and a decent standard of living for farmers, fifty years after its adoption. Moreover, this policy adapts to the changing needs of society and the new challenges, mostly preservation of the environment, nature and biodiversity in rural areas. Although the Common Agricultural Policy receives the largest share of European budget, the funds are decreasing over time, especially direct payments, which aim to provide basic income support to farmers in the European Union. On the other hand, agri-environmental payments are gaining importance. Policy decision-makers should be interested in the question of impacts of growing eco-conditionality of agricultural spending. New insights would help them to be successful in achieving the goals of sustainable agriculture. The purpose of this paper is to estimate the impacts of production support payments and rural development payments on the quality of groundwater. We use the small EU country Slovenia as an example. The baseline indicators are the level of nitrates and pesticides in groundwater, while the impacts were estimated using spatial error model. The results show that direct payments, coupled subsidies and investment grants raise the level of pesticides in groundwater, but do not have any statistically significant impact on the level of nitrates in groundwater. Furthermore, we did not find any statistically significant effects of agri-environmental payments on decrease of groundwater pollution with nitrates. However, our findings revealed that agri-environmental payments are effective in reducing pesticides in groundwater, although only to a limited extent. These results imply a problem of insufficient targeting of agri-environmental measures on the one hand, and suggest that greening of direct payments is necessary and entirely justified.  相似文献   
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Primary caregivers for victims of chronic illness and or trauma experience both positive and negative emotional consequences. These are broadly classified as compassion satisfaction (CS) and compassion fatigue (CF). Because one of the components of CF, burnout, varies with chronotype and sleep quality, we assessed the influence of chronobiological features on the broader constructs of CS and CF. Responses from primary ambulatory care oncology staff working dayshifts were assessed for potential relationships of chronotype and sleep quality with CS and CF using the professional quality of life scale. These were analyzed further in a multivariate model that included personality and job satisfaction as cofactors. We found that sleep quality was a key contributor to CS development and CF reduction. Morningness was positively linked to CS, but the univariate association was masked in the multivariate model. Job satisfaction (contingent rewards, nature of work and operating procedures) heavily influenced CS and CF development. Agreeableness and openness showed positive correlations with CS and negative with burnout, while emotional stability was linked to reduced CF. While job satisfaction and personality predictably played roles in the development of CS and CF, sleep quality and chronotype contributed significantly to benefits and negative consequences of providing care.  相似文献   
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Abstract A cluster of five to seven AKH-like immunoreactive cells lie in each lobe of the paired corpora cardiaca of the true armyworm, Pseudaletia unipuncta. These cells form a mesh work of immunoreactive processes within the corpora cardiaca, and immunoreactive tracts projecting posteriorly over the aorta.
Reversed-phase high performance liquid chromatography of extracts of the corpora cardiaca of P.unipuncta revealed a single large U.V. absorbent peak with a retention time identical to synthetic Manduca- AKH. Amino acid analysis of the contents of this peak yielded a composition identical to that of synthetic Manduca-AKH which was analysed in a parallel manner. Furthermore the material within the peak possessed adipokinetic activity when bioassayed in day 2 adult male P. unipuncta. The corpora cardiaca of similar individuals were found to contain approximately 17.6ng (17.6pmol) of Manduca-AKH equivalents per pair.
Injection of Manduca-AKH into 2-day-old adult male P.unipuncta resulted in a dose-dependent elevation in haemolymph lipid levels with a maximum level of 80–90μmg/μl obtained with 5–10 ng of Manduca-AKH. Continuous flight also elevated haemolymph lipid levels in day 4 adult males with a significant elevation evident in the first samples taken after 15 min of flight and lipid levels plateauing at approximately 100 μg/μl by about 60 min of flight.  相似文献   
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Abstract The body temperatures of six apterous species of Namib Desert tenebrionid beetles were measured continuously with indwelling thermocouples under laboratory conditions and in the field. The range of body temperatures selected was within the upper half of their 'tolerated range', which we defined as the temperatures lying between measured critical thermal maximum and critical thermal minimum. In the field, individuals also maintained their body temperatures within the upper half of the 'tolerated range'. These beetles maintained higher body temperatures than those recorded for any other ectothermic insect. Three of the six species maintained lower body temperatures in the field than they selected in the laboratory. The other three species showed no significant difference between field and laboratory body temperatures. We conclude that these beetles are not forced by biotic or abiotic factors to adopt thermal niches which present them with physiological difficulties.  相似文献   
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Abstract .Unilaterally antennectomized Heliothis virescens (F.) males flying close to the central axis of a plume of sex pheromone display no significant differences in behaviour compared to sham-operated males in course angles, track angles, airspeed and groundspeed. This demonstrates that right/left antennal information is not necessary for normal orientation movements in response to pheromone, but rather that it is 'blended' within the moth's central nervous system before pheromone-mediated manoeuvres are made. However, some unilaterally antennectomized moths (36%) make repetitive, asymmetrical, saw-tooth-shaped tracks during pheromone-mediated upwind progress, whereas control moths never make such tracks. Unilaterally antennectomized moths made such tracks on the side of the plume contralateral to the missing antenna. We hypothesize that these occasional asymmetrical tracks in unilaterally ablated males are the result of reiterative asymmetrical pheromone stimulation of a higher probability on track legs going toward rather than away from the long axis of the plume on males with a single antenna remaining on the 'away from axis' side. Combined with a greater propensity for treated moths to lock onto the plume away from the central axis on one side rather than the other, repetitive successive asymmetrical track legs (resulting in a saw-tooth-shaped track) are commonly observed in these moths. Control moths do also make asymmetric successive track legs but they rarely are repeated and thus are not readily observed.  相似文献   
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Abstract .Following parturition, the third instar larva of Glossina morsitans morsitans West begins a wandering period in which it crawls to the site of pupariation. The duration of wandering can be drastically shortened by pinching or by denying the larva physical contact with the substrate. Contact with water increases the wandering period. Duration of subsequent activities appears to be rigidly fixed. At the end of the wandering period, the larva quickly progresses through a stereotypic sequence of behaviours that include immobilization and excretion of a liquid from the anus, retraction of the anterior segments, cuticular shrinkage, and tanning. Muscular activity and mechanical changes in the cuticle are reflected in changes of haemocoelic pressure. Muscular contractions produce pressure pulses that gradually increase in frequency and intensity, reaching a peak during retraction of the anterior segments. Changes in the mechanical properties of the cuticle cause a more gradual elevation of baseline pressure as the cuticle shrinks and loses its plasticity. As tanning begins, muscular activity ceases and haemocoelic pressure gradually decreases. In spite of its unusual early development within the confines of the female's uterus, the free-living larva shows the full behavioural repertoire observed in other cyclor-rhaphous Diptera at pupariation.  相似文献   
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