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91.
Parental care is often characterized by complex behavioral interactions between offspring soliciting for food and parents providing food. During this interplay both behaviors, offspring begging and parental provisioning, can exert a selective pressure on the expression of the other. It has, therefore, been predicted that traits involved in this interplay may coevolve and ultimately become (genetically) correlated. Such covariation has—at least at the phenotypic level—been found in a number of cross-fostering studies, including evidence from the canary (Serinus canaria), our model species. However, a common challenge for these studies has been to establish a genetic covariation given the difficulty to disentangle the relative contribution of genetic and maternal effects, as the latter may act already before cross-fostering. We addressed this problem by studying within-individual covariation between begging (expressed at the nestling stage) and provisioning (expressed at the adult stage). In addition, we estimated the degree of heritability of these behaviors using parent-offspring regressions, as inheritance forms a prerequisite for any genetic correlation. Both traits showed a low to moderate non-significant heritability, similar to those previously reported in other bird species. However, offspring begging and parental provisioning did not covary at the intra-individual level. Thus, individuals begging intensively as nestlings were not necessarily individuals that provided more food as adults or vice versa. These findings provide important insights for our understanding of coadaptation, suggesting that factors other than genes such as maternal effects may play a role in adjusting offspring begging to the levels of parental provisioning.  相似文献   
92.
The Boles?aw–Bukowno mining area in Poland is highly polluted by elements such as Zn, Pb, Cd and As. The reactivity and mobility of toxic elements such as Tl are poorly known. Here, we studied by sequential extraction the mobility of As, Cd, Co, Cr, Cu, Mn, Mo, Pb, Tl and Zn in sediments from two water reservoirs near Bukowno. Results show that available As, Co, Mn, Pb and Zn are found in carbonate minerals. Available Cd, Cu and Tl are found in sulphides and organic matter. The extractability of As, Cr, Mo and Tl was rather poor. By contrast, 85 % of total Cd, Pb and Zn was mobile. We discuss Tl and Mo association in carbonate sediments from ore deposits.  相似文献   
93.
Environmental Science and Pollution Research - Phytoremediation, as a cost-effective, highly efficient, environmentally friendly, and green approach, gained attention to the removal of metals,...  相似文献   
94.
Environmental Science and Pollution Research - Solid particles impair the performance of the photovoltaic (PV) modules. This results in power losses which lower the efficiency of the system as well...  相似文献   
95.
In this study, tebuconazole (TEB)-loaded poly-3-hydroxybutyrate (P3HB)-based microparticles were developed and comprehensively characterized. TEB-loaded microparticles with the initial loading amounts of the fungicide of 10, 25, and 50% of the polymer mass (TEB 10, TEB 25, and TEB 50%) were prepared using emulsion technique. Encapsulation efficiency of TEB varied from 59 to 86%. As the loading amount was increased, the average diameter of microparticles increased too, from 41.3 to 71.7?µm, while zeta potential was not influenced by TEB loading, varying between –32.6 and –35.7?mV. TEB was gradually released from the microparticles to the model medium, and after 60?d, from 25 to 43% of TEB was released depending on the content of the encapsulated fungicide. The data obtained from in vitro TEB release were fitted to different mathematical models. It was shown that the release profiles of TEB could be best explained by the Zero-order, Higuchi, and Hixson–Crowell models. The antifungal activity of the P3HB/TEB microparticles against phytopathogenic fungi Fusarium moniliforme and Fusarium solani was demonstrated by in vitro tests conducted in Petri dishes. Thus, hydrophobic agrochemicals (TEB) can be effectively encapsulated into P3HB microparticles to construct slow-release formulations.  相似文献   
96.
Plant-parasitic nematodes, such as Meloidogyne incognita, cause serious damage to various agricultural crops worldwide, and their control necessitates environmentally safe measures. We have studied the effects of plant secondary metabolites on M. incognita locomotion, as it is an important factor affecting host inoculation inside the soil. We compared the effects to the respective behavioral responses of the model saprophytic nematode Caenorhabditis elegans. The tested botanical nematicides, all reported to be active against Meloidogyne sp. in our previous works, are small molecular weight molecules (acids, alcohols, aldehydes, and ketones). Here, we specifically report on the attractant or repellent properties of trans-anethole, (E,E)-2,4-decadienal, (E)-2-decenal, fosthiazate, and 2-undecanone. The treatments for both nematode species were made at sublethal concentration levels, namely, 1 mM (<EC50), and the chemical controls used for the experiments were the commercial nematicides fosthiazate and oxamyl. According to our results, trans-anethole, decenal, and oxamyl attract C. elegans, while 2-undecanone strongly attracts M. incognita. These findings can be of use in the development of nematicidal formulations, contributing to the disruption of nematode chemotaxis to root systems.  相似文献   
97.
Heavy metals, including cadmium (Cd), lead (Pb) and mercury (Hg) act as nephrotoxic agents, particularly in the renal cortex. The aim of the study was to determine the concentrations of Cd, Pb and Hg in kidneys removed from patients due to lesions of various etiologies and from patients after the rejection of transplanted kidneys. Additionally, we determined the influence of selected biological and environmental factors on the concentrations of toxic metals. The study material consisted of kidneys with tumor lesions (n = 27), without tumors (n = 7) and its extracted grafts (n = 10) obtained from patients belongs to the north-western areas of Poland. The determined metal concentrations in the renal cortex and medulla may be arranged in the following descending order: Cd > Pb > Hg. The highest concentrations of Cd and Hg were found in the cortex, while the maximum content Pb was observed in the medulla. Significant correlations were found in the concentrations of the same metals between cortex and medulla and between Pb and Hg in the renal medulla. Pb content was higher in the renal medulla of men than in the cortex of the elderly (above 60 years of age). The highest concentrations of Pb and Hg were found in the cortex and medulla, of the kidneys had not neoplastic changes, and lower content of these metals were found in the extracted kidney grafts. In summary, renal grafts accumulate less heavy metals than cancerous kidneys, what could have been caused by immunosuppressors taken by the graft recipients. Moreover, sex, age and smoking are key factors responsible for xenobiotics concentrations.  相似文献   
98.
Polymer poly(3-hydroxybutyrate) [P(3HB)] has been used as a matrix in slow-release formulations of the herbicide metribuzin (MET). Physical P(3HB)/MET mixtures in the form of solutions, powders, and emulsions were used to construct different metribuzin formulations (films, granules, pellets, and microparticles). SEM, X-Ray, and DSC proved the stability of these formulations incubated in sterile water in vitro for long periods of time (up to 49 days). Metribuzin release from the polymer matrix has been also studied. By varying the shape of formulations (microparticles, granules, films, and pellets), we were able to control the release time of metribuzin, increasing or decreasing it.  相似文献   
99.
The unique observations and experiences of users of suburban natural areas lead them to perceive their surroundings in a manner associated with their personal values. It follows that every individual has a unique cognitive decision-making structure. This paper examines users’ affective and cognitive evaluation of a particular suburban natural area by applying the means-end chain method to reveal the cognitive mechanism by which users link the attributes and benefits of an environmental public good with their own personal values. Analysis of a survey conducted of visitors to a Spanish suburban natural area (park) reveals the main attributes to be the opportunity to practice sports and proximity of the park and the main potential benefits to be the improvement of physical and psychological well-being. The desired personal values include fun, quality of life and self-fulfillment at the individual level and improved social relationships at the collective level. The paper also tests for cross-group, cognitive-structure differences in visitor groups, segmented by level of satisfaction and reported range of emotions, and finds that perceived physical and psychological health improvements and individual and social awareness increase with higher levels of satisfaction and emotional response. Therefore, the recommendations for natural area management suggested by these findings include enhancing the scenic beauty and peacefulness of suburban natural areas in order to improve the affective state of visitors because this could contribute to reducing social costs (including health care) within the area of influence of the natural area.  相似文献   
100.
Since the liberalisation of its investment regime in the 1990s, Argentina has seen a rise in foreign direct investment into large-scale exploration and exploitation of mineral resources. However, many social groups (local communities, grassroots movement and the church) often strongly oppose new mining projects on the grounds of environmental, ethical and economic concerns. In a situation marked by widespread conflict, mining companies continue operating and develop Corporate Social Responsibility (CSR) initiatives which are often promoted as a means of contributing to the sustainability and development of the nation. The paper develops a framework to highlight how the principles of stakeholder theory could be used as conceptual and practical guidance for conflict-resolution oriented CSR policies. The framework is further used to analyse two case studies of conflictive mining projects in Argentina. The paper explores how key stakeholders perceive contribution of CSR to welfare and the socio-economic development of mining communities and sustainable development of the nation. It demonstrates that institutional and social stakeholder networks often strongly oppose the idea of voluntary self-regulation implied by CSR in situations characterised by weak governance. Even though the CSR of companies could be improved in areas of corporate communication, transparency, stakeholder engagement and dialogue, it is not seen as a panacea for the social conflicts in the sector.  相似文献   
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