Abstract: Diatom growth strategies, which are used as a proxy to analyze disturbances and environmental impacts, can also provide reliable information about environmental gradients. In this study, we used diatom communities and biological traits to assess the structure of epilithic diatoms after an oil spill in a large tributary of the Iguaçu River (Paraná, Brazil). Epilithon and water samples were taken on July 12th, 2004, and after an unexpected oil spill, on the following days: 09/19, 10/03, and 10/13/2004. We observed that the spill caused a distinct shift in both diatom composition and guild group. Diversity decreased and pollution-tolerant diatoms of the motile group became dominant in response to the elevated nutrient levels and reduced light. Tube-forming diatoms, which are strong competitors for light, dominated the epilithon 24 days after the oil spill. Both diatom guilds and growth forms were successfully used to predict the environmental conditions. While diatom guilds responded to disturbances along a temporal gradient, changes inside the guilds were the main factor for understanding the environmental gradient.

Esta pesquisa foi realizada com o objetivo de determinar o efeito da inclusão de cal virgem e cloreto de sódio sobre as perdas fermentativas e a estabilidade aeróbia de silagens de cana-de-açúcar. O delineamento experimental utilizado foi o totalmente ao acaso em esquema de parcelas subdivididas com quatro repetições, de modo que os aditivos foram avaliados nas parcelas (silagem sem aditivo; silagens contendo 0,5; 1,0 e 2,0% de cloreto de sódio; e silagens contendo 0,5; 1,0 e 1,5% de cal virgem na matéria natural) e os tempos de exposição ao oxigênio nas subparcelas. Após 75 dias da ensilagem, os silos foram abertos para determinação dos teores de matéria seca (MS) e da perda de MS por efluente e gases e aferição da temperatura e do pH da silagem. A inclusão de cal nas silagens, independentemente da dose utilizada, proporcionou maior teor de MS e menor perda de MS. As menores temperaturas foram observadas nas silagens tratadas com cloreto de sódio. Os aditivos utilizados, sobretudo o cloreto de sódio, foram eficientes em manter a estabilidade aeróbia da silagem de cana.

The objective of this work was to determine the inclusion of whitewash and sodium chloride on the fermentative losses and aerobic stability of sugarcane silages. It was used a completely randomized experimental design in split plot scheme with four replicates, so the additives were evaluated in the plots (silage without additive, silages containing 0.5; 1.0 and 2.0% of sodium chloride; and silages containing 0.5; 1.0 and 1.5% of whitewash, on the basis of natural matter) and the time of exposition to oxygen was evaluated in the subplots. After 75 days from ensilage, silos were opened for determination of the contents of dry matter (DM) and the loss of dry matter by effluent and gases and checking of temperature and pH of the silage. The addition of whitewash into silages, regardless to the dose utilized, provides greater DM content and smaller loss of DM. The lowest temperatures were found in the silages treated with sodium chloride. The additives utilized were efficient in keeping the aerobic stability of sugar cane silage, particularly sodium chloride.

In vivo proton magnetic resonance spectroscopy (¹H-MRS) is a technique capable of assessing biochemical content and pathways in normal and pathological tissue. In the brain, ¹H-MRS complements the information given by magnetic resonance images. The main goal of the present study was to assess the accuracy of ¹H-MRS for the classification of brain tumors in a pilot study comparing results obtained by manual and semi-automatic quantification of metabolites. In vivo single-voxel ¹H-MRS was performed in 24 control subjects and 26 patients with brain neoplasms that included meningiomas, high-grade neuroglial tumors and pilocytic astrocytomas. Seven metabolite groups (lactate, lipids, N-acetyl-aspartate, glutamate and glutamine group, total creatine, total choline, myo-inositol) were evaluated in all spectra by two methods: a manual one consisting of integration of manually defined peak areas, and the advanced method for accurate, robust and efficient spectral fitting (AMARES), a semi-automatic quantification method implemented in the jMRUI software. Statistical methods included discriminant analysis and the leave-one-out cross-validation method. Both manual and semi-automatic analyses detected differences in metabolite content between tumor groups and controls (P < 0.005). The classification accuracy obtained with the manual method was 75% for high-grade neuroglial tumors, 55% for meningiomas and 56% for pilocytic astrocytomas, while for the semi-automatic method it was 78, 70, and 98%, respectively. Both methods classified all control subjects correctly. The study demonstrated that ¹H-MRS accurately differentiated normal from tumoral brain tissue and confirmed the superiority of the semi-automatic quantification method.

High resolution proton nuclear magnetic resonance spectroscopy (¹H MRS) can be used to detect biochemical changes in vitro caused by distinct pathologies. It can reveal distinct metabolic profiles of brain tumors although the accurate analysis and classification of different spectra remains a challenge. In this study, the pattern recognition method partial least squares discriminant analysis (PLS-DA) was used to classify 11.7 T ¹H MRS spectra of brain tissue extracts from patients with brain tumors into four classes (high-grade neuroglial, low-grade neuroglial, non-neuroglial, and metastasis) and a group of control brain tissue. PLS-DA revealed 9 metabolites as the most important in group differentiation: γ-aminobutyric acid, acetoacetate, alanine, creatine, glutamate/glutamine, glycine, myo-inositol, N-acetylaspartate, and choline compounds. Leave-one-out cross-validation showed that PLS-DA was efficient in group characterization. The metabolic patterns detected can be explained on the basis of previous multimodal studies of tumor metabolism and are consistent with neoplastic cell abnormalities possibly related to high turnover, resistance to apoptosis, osmotic stress and tumor tendency to use alternative energetic pathways such as glycolysis and ketogenesis.

Faecal samples from 79 wild boars (Sus scrofa scrofa) were examined by sedimentation method, zinc sulfate flotation method, and centrifugal flotation in sugar solution for endoparasites research. The results showed that 97.5% of the samples were positive for helminths and/or protozoa as follows: strongilides (70.9%), Ascaris suum (46.9%), Trichuris suis (29.1%), Metastrongylus sp. (12.6%), Strongyloides ransomi (3.8%), Balantidium coli (38.0%), Entamoeba spp. (15.2%), Giardia spp. (1.3%), Blastocystis sp. (12.6%). The frequency of Entamoeba was higher in young animals. Coccidian oocysts were observed in 59.5% samples and five species of Eimeria and one Isospora were recovered: Eimeria scabra (31.9%), E. deblieck (31.9%), E. perminuta (23.4%), E. cerdonis (17.0%), E. scrofae (12.8%) and Isospora suis (12.8%).