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111.
Phosphorus, manganese, sulfur (S), lead, and strontium of atmospheric total suspended particulate matter, sampled during the rainy season and the dry season 2002 at the Ilha Grande Island (Rio de Janeiro State, Brazil) have been analyzed by XRF techniques. The results showed total mean concentrations of 27?±?16 ng P m-3, 11?±?7 ng Mn m-3, 159?±?126 ng S m-3, 4.3?±?2.6 ng Pb m-3, and 208?±?148 ng Sr m-3. Generally, there is no clear influence of the two different climatic periods on the concentrations of most analyzed trace elements, with exception of sulfur the mean concentration of which, during the dry season, is about 60% higher than during the rainy season. This is probably due to biomass burning, a common practice in the Brazilian Southeast and Amazon region and/or to the presence of marine aerosols. The linear correlation coefficients strongly suggest the same source for P, Pb, and Mn. Some Pb, Mn, and P concentrations are in the range of typical values of urban areas. Potential sources of such elements are the urban and industrial emissions from the States of Rio de Janeiro and/or São Paulo.  相似文献   
112.
Echinococcus granulosus infection is a problem of public health in livestock-rearing regions of Latin America, like in Peru. This species is characterized by the morphometry of the large and small rostellar hooks in both metacestodes and adult worms. The aim of this work was to study biometrical characteristics of rostellar hooks in hydatid cysts (lung and liver) from some Peruvian provinces (Arequipa, Cuzco, Huancavelica, Junin and Puno). The biometrical analysis was obtained in a digital system for image analysis. The following parameters were studied: area, perimeter, length and width total of the handle, the blade and the distance between the blade and the guard of large and small hooks. For statistical analysis Student's t-test and Analysis of Variance (ANOVA) with Pos-test of Tukey were used, considering the values of p< or =0.05 as of statistic significance. All morphometric characters of large and small hooks were highly significant (p<0.000), when data were compared among the samples from the different provinces. Rostellar hooks in specimens from Huancavelica presented smallest measurements, whereas hooks in specimens from Junin were bigger in relation to the total and blade measurements. Generally, samples from Arequipa presented the biggest large hooks in relation to the handle parameters. The rostellar hooks of cattle and sheep hosts varied depending on the geographic localization, host and organ. Hooks recovered from the lungs were larger than those collected in the liver. It was concluded that morphometry using computer image analysis allows the characterization of E. granulosus. The rostellar hooks presented morphometric polymorphism.  相似文献   
113.
114.
Cycas revoluta (Cycadaceae) is commonly cultivated as an ornamental tree in several countries. In April 2015, C. revoluta leaves showing brownish spots with a yellow halo that progressed to leaflet necrosis were observed in Belém, Pará state, Brazil. This study aimed to determine the aetiology of this disease on sago palm in Brazil. Based on DNA sequence-based phylogeny, morphology, and colony characterization, the fungus was identified as Pseudopestalotiopsis elaeidis. To the best of our knowledge, this is the first report of P. elaeidis associated with leaf spots on C. revoluta worldwide.  相似文献   
115.
Management of soils to facilitate plant beneficial microbial interactions requires basic knowledge of the species composition and microbial community structures in the plant rhizosphere. Here, we examined composition of bacterial communities associated with rhizosphere microsites located at the root tips and mature root zones of Lolium perenne when grown in Chilean ash-derived volcanic soils (Andisols: Freire and Piedras Negras soil series). Community structures were analyzed by pyrosequencing of 16S ribosomal RNA (rRNA) genes followed by in silico analysis for phylogenetic assignments (MOTHUR and Visualization tool for Taxonomic Compositions of Microbial Community (VITCOMIC)). Analysis of the community structure revealed significant differences in community structures in relation to the soil series, which differed particularly in the relative abundance of Cyanobacteria and Firmicutes. However, no significant differences were observed with respect to root microsite location in the same Andisol series. Predominant taxa included members of the Proteobacteria, Actinobacteria, and Acidobacteria. Analysis by VITCOMIC showed that dominant bacterial groups comprised only 5 to 10 % of the total bacterial community and the remaining majority of bacteria included low-abundant taxa (Fusobacteria, Thermotogae, Lentisphaerae, Tenericutes, Deferribacteres Spirochaetes, Planctomycetes, Thermotogae, and Deinococcus-Thermus), most of which have not been previously reported or associated with the plant rhizosphere according to GenBank database. The results indicate that most of bacteria in the Chilean Andisols have not been described to the rhizosphere plants and their functional traits are still largely unknown.  相似文献   
116.

Purpose

Information on the effects of eucalyptus forests on hydrosedimentological processes is scarce, particularly at the catchment scale. Monitoring and mathematical modeling are efficient scientific tools used to address the lack of information for natural resource management and the representation and prediction of those processes. This study evaluates the effects of eucalyptus cultivation on hydrosedimentological processes in watersheds and to use the Limburg soil erosion model (LISEM) to represent and predict hydrological processes.

Material and methods

The study was conducted in two forested watersheds: the main watershed (94.46 ha) and a nested sub-watershed (38.86 ha), both cultivated with eucalyptus and residual riparian native forest, located in southern Brazil. Hydrosedimentalogical monitoring was conducted from 16th February 2011 to 31st December 2012, and LISEM model calibrations were performed on the bases of six storms events.

Results and discussion

The sediment yield for 2011 was 41.6 Mg km?2 and 38.5 Mg km?2 for the watershed and sub-watershed, respectively. An extreme event in 2012 provided greater sediment yield for the sub-watershed (99.8 Mg km?2) than that for the watershed (51.7 Mg km?2). Rainfall events with a greater maximum intensity generated rapid discharge and suspended sediment concentration responses in the sub-watershed due to the smaller drainage area and steeper landscape. In the main watershed, the accumulation of flood waves occurred for most events, with less steep hydrographs, and a later occurrence of the discharge peak after that of the sub-watershed. The LISEM adequately reproduced the peak discharge and runoff for the calibrated events; however, the peak time and the shape of the hydrograph were not adequately represented.

Conclusions

The hydrosedimentological patterns of the watershed and sub-watershed, both cultivated with eucalyptus, was characterized by sedimentographs preceding hydrographs during rainfall–runoff events where scale effects occur, with maximum discharge and specific sediment yield greater in the watershed than that in the sub-watershed. Empirical models based on hydrologic variables may be used for estimating the suspended sediment concentration and sediment yield. Therefore, LISEM may be used for the prediction of hydrological variables in these forested watersheds.  相似文献   
117.
Anthracnose caused by species of Colletotrichum is considered one of the main postharvest diseases for avocado. In this study, Colletotrichum isolates associated with avocado anthracnose, collected in different states of Brazil, were evaluated through phylogenetic analysis, morphological characterization, and pathogenicity assays. Moreover, the events during pathogen infection of avocados were examined by scanning electron microscopy. To assess the genetic diversity of 54 Colletotrichum isolates, partial sequence analysis of the gene gapdh was performed. According to the generated groupings and the geographical origins of isolates, a subset of 14 strains was selected for performing multilocus phylogeny analysis (using sequences of gapdh, act, tub2, and ApMat). Two species previously described were identified: C. siamense belonging to the C. gloeosporioides species complex and Colletotrichum karstii belonging to the C. boninense species complex. All Colletotrichum strains evaluated caused typical symptoms of anthracnose in avocado fruits. Conidia of the most virulent strain germinated between 6 and 12 hr after inoculation (hai). Penetration through wounds occurred 48 hai, tissue colonization occurred between 144 and 240 hai, and sporulation took place at 240 hai via the production of an acervulus, conidiophores, and conidia. The findings shed light on the aetiology of avocado anthracnose in Brazil and provide a better understanding of the infection process of this pathogen, which may assist in the development of disease management strategies.  相似文献   
118.
The effect of coffee on cardiovascular diseases is still controversial. It is known that the process of decaffeination may influence the chemical constitution and, therefore, the biological effects of coffee. This study thus evaluated the effects of decaffeination on the levels of total phenols and chlorogenic acids in Coffea arabica L. samples, as well as the effects of ingesting both integral and decaffeinated coffee on the lipid profile and hemostatic and hematological parameters in normal and hyperlipidemic rats. Samples of integral and decaffeinated lyophilized coffee (Coffea arabica L., planted in Brazil) were used for chemical analysis (total phenols, chlorogenic acid and caffeine contents). For the bioassays, coffee beverages were prepared with non-lyophilized samples (10 % w/v) and were filtered and administered to animals by gavage (7.2 mL/kg/day) over 30 days. On the 31st day after beginning the treatment with coffee beverages, hyperlipidemia was induced to the animals by administering Triton WR-1339 (300 mg/kg body weight). On day 32, blood was taken to determine the lipid profile, platelet aggregation, prothrombin time, partially activated thromboplastin time and hemogram. The contents of both phenolic compounds and chlorogenic acid in the integral coffee beverage were significantly lower than those in the decaffeinated coffee beverage. The animals treated with Triton WR-1339 presented a mixed hyperlipidemia. Although the decaffeination process caused a relative increase in total phenols and chlorogenic acids, the coffee drinks were unable to change the lipid profile or the hemostatic and hematological parameters in the studied animals.  相似文献   
119.
Mammary invasive micropapillary carcinoma is a rare variant of mammary carcinoma that was recently recognized in dogs. The cytologic features and biologic behavior of such neoplasms in dogs have not yet been widely discussed in the veterinary literature. We report the clinical, cytologic, and histologic features of a canine micropapillary carcinoma in a 13‐year‐old female mongrel dog. The mammary region presented with extreme local pain, severe edema and erythema, and multifocal epidermal ulceration, which is typical for an inflammatory mammary carcinoma. Fine‐needle aspirates were highly cellular and consisted of individual cells and papillary cell clusters with characteristics of malignant epithelial cells. Histologic examination revealed neoplastic cells arranged in small papillae without fibrovascular cores, sometimes inside clear lymphatic spaces, indicating lymphovascular invasion. Regional lymph node evaluation revealed metastatic cells. Due to deteriorating clinical condition the dog was euthanatized 5 months after mastectomy. At necropsy, metastatic neoplastic mammary cells were found in popliteal and mediastinal lymph nodes, the right femoral biceps muscle, liver, heart, lungs, and urinary bladder.  相似文献   
120.
The aim of this study was to assess the effect of the Chilean rodeo exercise on some blood constituents, classically used to assess welfare, during rest; training with and without steer; and before and after official competitions. During the training season, 13 horses were assessed at their farms of origins, and samples were taken at rest and after training with and without a steer; then during the competition season, 16 horses were assessed at four different times, one before and three after the competition. The blood constituents assessed were packed cell volume (PCV), total proteins, fibrinogen, cortisol, neutrophil:lymphocyte ratio, creatine phosphokinase, aspartate transaminase, glutathione peroxidase, and serum amyloid A. Analysis of variance for repeated measures was applied using the Statistix 8.0 software, and a significance level of P < .05 was applied. For horses assessed during exercise with and without a steer, significant differences were observed for PCV, which were significantly lower at rest than after both exercises, and total proteins, which showed a significant increase only after exercise with steer. In the case of official competitions, PCV was significantly higher immediately after rodeo, and the lowest value for cortisol was observed the evening after competition (P < .05); among the enzymes assessed, creatine phosphokinase plasma concentrations immediately after rodeo and the evening after competition were significantly higher than concentrations the next morning. The use of physiological indicators did not seem to be sufficient to assess the overall effect of rodeo on the welfare of these horses, and other types of indicators should be considered in future studies.  相似文献   
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