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971.
  1. Governance of natural resources in the Amazon has changed over time, especially when it comes to participatory regimes. Yet these regimes have rarely focused on the conservation of aquatic systems or have failed to fully deliver social justice.
  2. Participatory regimes in the Amazon basin that rely on the provision of freshwater ecosystem services can potentially favour transformative and just conservation. A framework referred to as the ‘Just Aquatic Governance’ model is proposed to organize and facilitate the transition of continuing and future endeavours that seek conservation while also supporting distinct aspects of social justice.
  3. If conservation of aquatic systems can be reconciled with all aspects of social justice, then transformative and just governance regimes could emerge without further burdening those at the forefront of conservation.
  4. The Just Aquatic Governance framework is divided into three aspects of social justice, organized according to the following pillars: (i) recognitional – support for cultural diversity and the maintenance of livelihoods, including food security; (ii) procedural – the right to autonomy and territory, and support for participatory forms of governance; and (iii) distributional – promotion of gender equality and fair distribution of economic benefits.
  5. Although not a panacea, the model proposed here, which can also influence policy strategies, can potentially align both conservation demands and social aspirations in the Amazon – a historical, yet still imperative, need in the region.
  相似文献   
972.
  1. The dusky grouper Epinephelus marginatus is a large epinephelid species that occurs in the eastern and south-western Atlantic and western Indian Oceans. Late maturity, protogynous hermaphroditism, site fidelity, and overfishing have all contributed to its demographic decline.
  2. Connectivity and demography within a broad sampling of dusky grouper populations throughout its distribution were assessed. To do so, genetic variation at 11 polymorphic microsatellite loci and a partial sequence of the mitochondrial control region (mtCR) were evaluated.
  3. Two major mtCR lineages with a sequence divergence of 1.6% were found. The magnitude of genetic differentiation for mtCR among north and south Atlantic and Indian Ocean populations was high, with ΦST = 0.528.
  4. DEST and results of discriminant analysis of principal component revealed significant microsatellite genetic differentiation between all collection areas. Significant pairwise DEST showed moderate (0.084) to very great (0.603) differentiation. The effective population size was low for all localities, ranging between 25 (Azores Archipelago) and 311 (Rio Grande do Sul). The overall effective population size was estimated as 299 (confidence interval = 215–412), and there was no evidence of strong or recent bottleneck effects.
  5. Local and regional genetic structuring among dusky grouper populations is the consequence of the species' site fidelity, distribution across multiple oceanographic boundaries, and probably also of sequential hermaphroditism that contributes to the intensity of random genetic drift.
  6. The spatial pattern of genetic structuring of dusky groupers is such that fisheries management and conservation of population genetic integrity will have to be pursued at the local and regional scales.
  相似文献   
973.
974.
Precision Agriculture - Precision agriculture provides detailed information on the spatial variability of soil properties, including nutrient content, allowing for local-specific decision making....  相似文献   
975.

Coffee beverage quality is highly correlated with the degree of fruit ripeness. In this sense, monitoring fruit ripeness is of utmost importance for harvest planning and, especially for obtaining high-quality beverages. Currently, this process is carried out through manual counts of unripe fruits, which is laborious and limited to a few plants within the field. This study aimed at evaluating the potential of a low-cost multispectral camera for coffee ripeness monitoring in the Zona da Mata region of Minas Gerais State, Brazil. For that, five fields of Arabica coffee with distinct characteristics were evaluated. During the coffee ripeness period, four flights were carried using a Phantom 4 Pro quadcopter equipped with a Mapir Survey 3W camera for imagery acquisition. After that, nine vegetation indices (VIs) were obtained. For the same dates, the percentage of unripe fruits was obtained using an irregular grid in all fields. The data was split into two ripeness classes: suitable for harvest (R) with?<?30% of unripe fruits; and not suitable for harvest (U), with?>?30% of unripe fruits. Then, a principal component analysis was used to infer the importance of the VIs to discriminate plants with unripe fruits from those with ripe fruits. The first two principal components explained?>?75% of the variance in the datasets from all coffee fields. The VIs were able to discriminate the ripeness classes (U and R) in most fields; however, their performance was directly influenced by the crop yield and canopy volume.

  相似文献   
976.
The evolution of complex organs is a source of controversy because they require the contributions of many adaptations to function properly. We argue that placentas are complex, that they have evolved multiple times in Poeciliopsis, and that there are closely related sister taxa that have either no placentas or intermediate stages in the evolution of a placenta. Furthermore, placentas can evolve in 750,000 years or less, on the same time scale as suggested by theoretical calculations for the evolution of complex eyes. Independent origins of such complexity, accompanied by sister taxa that either lack or have intermediate stages in the evolution of the trait, present an opportunity to study the evolution of novelty and complexity from a comparative, evolutionary perspective.  相似文献   
977.
Agroforestry Systems - Pepper producers are searching for more sustainable production systems. Shaded cultivation is presented as a management option to attenuate black pepper environmental...  相似文献   
978.
Chemical, nutritional, and technological characteristics of buckwheat and non-prolamine buckwheat flours in comparison to wheat for celiac patients use have been studied. The results suggested the following conclusions: the 56.5% extraction value for flour obtention is considered good; the buckwheat flour presents methionine and cystine as first limiting amino acids followed by threonine as the second limiting amino acid; the buckwheat flour presents higher content of lysine amino acids than the wheat flour; the buckwheat flour is superior to the wheat flour regarding iron, copper, and magnesium minerals; the buckwheat flour does not present haemagglutinin activity and the tannin content is negligible. Rheological assays indicate that the buckwheat flour does not contain gluten.  相似文献   
979.
The food industry produces a large amount of onion wastes, making it necessary to search for possible ways for their utilization. One way could be to use these onion wastes as a natural source of high-value functional ingredients, since onion are rich in several groups of compounds, which have perceived benefits to human health. The objective of this work is to gain knowledge of any differences between the different onion wastes obtained from industry and non-commercial bulbs to use them as food ingredients rich in specific compounds. The results showed that brown skin and top–bottom could be potentially used as functional ingredient rich in dietary fibre, mainly in insoluble fraction, and in total phenolics and flavonoids, with high antioxidant activity. Moreover, brown skin showed a high concentration of quercetin aglycone and calcium, and top–bottom showed high concentration of minerals. Outer scales could be used as source of flavonols, with good antioxidant activity and content of dietary fibre. However, inner scales could be an interesting source of fructans and alk(en)yl cystein sulphoxides. In addition, discarded onions (cvs Recas and Figueres) could be used as a good source of dietary fibre, and cv Recas also as a source of phenolics compounds.  相似文献   
980.
Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. We extracted six fucans from Canistrocarpus cervicornis by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucuronic acid, galactose and sulfate. No polysaccharide was capable of prolonging prothrombin time (PT) at the concentration assayed. However, all polysaccharides prolonged activated partial thromboplastin time (aPTT). Four sulfated polysaccharides (CC-0.3/CC-0.5/CC-0.7/CC-1.0) doubled aPTT with only 0.1 mg/mL of plasma, only 1.25-fold less than Clexane, a commercial low molecular weight heparin. Heterofucans exhibited total antioxidant capacity, low hydroxyl radical scavenging activity, good superoxide radical scavenging efficiency (except CC-1.0), and excellent ferrous chelating ability (except CC-0.3). These results clearly indicate the beneficial effect of C. cervicornis polysaccharides as anticoagulants and antioxidants. Further purification steps and additional studies on structural features as well as in vivo experiments are needed to test the viability of their use as therapeutic agents.  相似文献   
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