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Plant Foods for Human Nutrition - Obesity is an important public health concern and is directly related with chronic noncommunicable diseases that affect the health of millions of people around the...  相似文献   
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This study investigated the secondary stress responses of Paralichthys orbignyanus exposed to ammonia and nitrite and after recovery. Fish were exposed to 0.12, 0.28, and 0.57 mg NH3‐N/L, or 5.72, 10.43, and 15.27 mg NO2‐N/L for 10 d followed by the same time length for recovery. Ammonia‐ and nitrite‐free water was used as a control treatment. Blood samples were collected after 1, 5, and 10 d of exposure and after recovery. Fish exposed to ammonia presented lower and higher glucose levels after 10 d of exposure and recovery, respectively. Ammonia induced initial and transient ionic disturbances and metabolic alkalosis. Nitrite exposure caused hyperglycemia, increased plasma K+ levels, and respiratory alkalosis, whereas metabolic acidosis was observed after recovery. Increased proportion of monocytes and/or granulocytes and reduced number of lymphocytes were demonstrated in fish exposed to 0.28 mg NH3‐N/L (Day 1) and 10.43 mg NO2‐N/L (Day 5) and after recovery in the 0.28 and 0.57 mg NH3‐N/L treatments. Exposure to ammonia decreased the proportion of granulocytes on Day 5. In conclusion, exposure to concentrations at 0.12 mg NH3‐N/L and 5.72 mg NO2‐N/L provoked physiological disorders in Brazilian flounder. Nonetheless, fish exposed to 5.72 mg NO2‐N/L following a 10‐d recovery period showed complete resumption of homeostasis.  相似文献   
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The Brazilian Amazon is endemic for malaria and natural infections by Plasmodium spp. have been detected in Neotropical primates. Despite the diversity of primate species in the region, studies on infections by these agents are limited. The aim of the present study was to investigate the frequency of infection by Plasmodium vivax and P. falciparum in free‐born primates that were kept in captivity, in the western Amazon, Brazil. Blood samples were collected from 98 Neotropical primates. Detection of P. vivax and P. falciparum DNA was performed using a semi‐nested PCR, and the amplified products were sequenced. Plasmodium spp. DNA was detected in 6.12% (6/98) of the primates. P. vivax, and P. falciparum DNA was detected in 2.04% (2/98) and 4.08% (4/98) of these mammals, respectively. Sequencing and phylogenetic analysis confirmed the results obtained from the semi‐nested PCR. The presence of infected non‐human primates (NHP) can be auxiliary in the maintenance of P. falciparum and P. vivax and may have implications for the malaria surveillance and control in the Brazilian Amazon. It is necessary to structure an efficient surveillance system for the aetiological agents of malaria that infect NHP and humans to reduce the risk of Plasmodium spp. introduction into new areas, to protect all susceptible species.  相似文献   
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Context

Land-use/land-cover (LU/LC) dynamics is one of the main drivers of global environmental change. In the last years, aerial and satellite imagery have been increasingly used to monitor the spatial extent of changes in LU/LC, deriving relevant biophysical parameters (i.e. primary productivity, climate and habitat structure) that have clear implications in determining spatial and temporal patterns of biodiversity, landscape composition and ecosystem services.

Objectives

An innovative hierarchical modelling framework was developed in order to address the influence of nested attributes of LU/LC on community-based ecological indicators.

Methods

Founded in the principles of the spatially explicit stochastic dynamic methodology (StDM), the proposed methodological advances are supported by the added value of integrating bottom-up interactions between multi-scaled drivers.

Results

The dynamics of biophysical multi-attributes of fine-scale subsystem properties are incorporated to inform dynamic patterns at upper hierarchical levels. Since the most relevant trends associated with LU/LC changes are explicitly modelled within the StDM framework, the ecological indicators’ response can be predicted under different social-economic scenarios and site-specific management actions. A demonstrative application is described to illustrate the framework methodological steps, supporting the theoretic principles previously presented.

Conclusions

We outline the proposed multi-model framework as a promising tool to integrate relevant biophysical information to support ecosystem management and decision-making.
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Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they...  相似文献   
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Journal of Soils and Sediments - Phosphorus (P) is often the main limiting factor for plant growth in highly weathered tropical soils. Phosphate use efficiency and crop yields could be increased in...  相似文献   
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The antinociceptive and anti-inflammatory activity of caulerpin was investigated. This bisindole alkaloid was isolated from the lipoid extract of Caulerpa racemosa and its structure was identified by spectroscopic methods, including IR and NMR techniques. The pharmacological assays used were the writhing and the hot plate tests, the formalin-induced pain, the capsaicin-induced ear edema and the carrageenan-induced peritonitis. Caulerpin was given orally at a concentration of 100 μmol/kg. In the abdominal constriction test caulerpin showed reduction in the acetic acid-induced nociception at 0.0945 μmol (0.0103–1.0984) and for dypirone it was 0.0426 μmol (0.0092–0.1972). In the hot plate test in vivo the inhibition of nociception by caulerpin (100 μmol/kg, p.o.) was also favorable. This result suggests that this compound exhibits a central activity, without changing the motor activity (seen in the rotarod test). Caulerpin (100 μmol/kg, p.o.) reduced the formalin effects in both phases by 35.4% and 45.6%, respectively. The possible anti-inflammatory activity observed in the second phase in the formalin test of caulerpin (100 μmol/kg, p.o.) was confirmed on the capsaicin-induced ear edema model, where an inhibition of 55.8% was presented. Indeed, it was also observed in the carrageenan-induced peritonitis that caulerpin (100 μmol/kg, p.o.) exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 48.3%. Pharmacological studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive and anti-inflammatory actions and also to identify other active principles present in Caulerpa racemosa.  相似文献   
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The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition.  相似文献   
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