Phylogenetic analysis of the order Pleuronectiformes (Teleostei) based on sequences of 12S and 16S mitochondrial genes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Electrochemical behavior of metallic chromium in chloride media

The electrochemical behavior of metallic chromium in aqueous solutions containing chloride ions at different pH was studied by means of open-circuit potential vs. time measurements, cyclic voltammetry and electrochemical impedance spectroscopy. The composition of the surface oxides was analyzed by XPS. For solutions with pH<3 the formation of a passive layer occurs via a dissolution/precipitation process while for pH>3 the mechanism changes. XPS analysis revealed that Cr2O3 basically constitutes the passive layer.

Acid and fermented silage characterization and determination of apparent digestibility coefficient of crude protein for pacu Piaractus mesopotamicus

Three types of raw materials including commercial waste from saltwater (SW), freshwater fish (FW) and tilapia fillet residue (FR) were used to produce fish silage by either acid digestion (2% formic acid and 2% sulfuric acid) or anaerobic fermentation (5% of Lactobacillus plantarum and 15% sugar cane molasses). Six test diets were used in digestibility trials prepared with 70% reference diet and 30% of each experimental silage. These diets were fed to juvenile pacu Piaractus mesopotamicus (146 g average weight) in triplicate. Fish were kept in 500-L tanks and feces collected by manual extrusion. It was observed for both processes that SW waste always had the highest moisture content and lowest fat and ash. Highest crude protein levels were found in silages from commercial fish waste (SW and FW) made from whole fish unfit for human consumption. However, apparent digestibility coefficients did not vary among diets (P > 0.05). Although values did not differ statistically, fermented silage consistently displayed higher digestibility coefficients compared to acid silage. The silages exhibited relatively high protein digestibility (72.5-80.0%), thus suggesting the feasibility of using fish industry by-products in aquaculture feeds.

Ácaros associados a plantas da região Core do Cerrado e sua influência na acarofauna em cultivos de soja (Glycine max (L.) Merril) (Fabaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudios citogenéticos en teleosteos marinos y dulceacuícolas de venezuela

Pós-graduação em Ciências Biológicas (Zoologia) - IBB

Does disturbance affect bud bank size and belowground structures diversity in Brazilian subtropical grasslands?

Brazilian Campos grasslands are ecosystems under high frequency of disturbance by grazing and fires. Absence of such disturbances may lead to shrub encroachment and loss of plant diversity. Vegetation regeneration after disturbance in these grasslands occurs mostly by resprouting from belowground structures. We analyzed the importance of bud bank and belowground bud bearing organs in Campos grasslands. We hypothesize that the longer the intervals between disturbances are, the smaller the size of the bud bank is. Additionally, diversity and frequency of belowground organs should also decrease in areas without disturbance for many years. We sampled 20 soil cores from areas under different types of disturbance: grazed, exclusion from disturbance for two, six, 15 and 30 years. Belowground biomass was sorted for different growth forms and types of bud bearing organs. We found a decrease in bud bank size with longer disturbance intervals. Forbs showed the most drastic decrease in bud bank size in the absence of disturbance, which indicates that they are very sensitive to changes in disturbance regimes. Xylopodia (woody gemmiferous belowground organs with hypocotyl-root origin) were typical for areas under influence of recurrent fires. The diversity of belowground bud bearing structures decreased in the absence of disturbance. Longer intervals between disturbance events, resulting in decrease of bud bank size and heterogeneity of belowground organs may lead to the decline and even disappearance of species that relay on resprouting from the bud bank upon disturbance. (C) 2014 Elsevier GmbH. All rights reserved.

Water use of Juniperus virginiana trees encroached into mesic prairies in Oklahoma, USA

Juniperus virginiana (eastern redcedar) is encroaching into mesic prairies of the southern Great Plains, USA, and is altering the hydrologic cycle. We used the thermal dissipation technique to quantify daily water use of J. virginiana into a mesic prairie by measuring 19 trees of different sizes from different density stands located in north-central Oklahoma during 2011. We took the additional step to calibrate our measurements by comparing thermal dissipation technique estimates to volumetric water use for a subset of trees. Except for days with maximum air temperature below -3 degrees C, J. virginiana trees used water year round, reached a peak in late May, and exhibited reduced water use in summer when soil water availability was low. Overall daily average water use was 24 l (+/- 21.81 s.d.) per tree. Trees in low density stands used more water than trees with similar diameters from denser stands. However, there was no difference in water use between trees in different density stands when expressed on a canopy area basis. Approximately 50% of variation in water use that remained after accounting for the factors site, tree, and day was explained using a physiologically-based model that included daily potential evapotranspiration, maximum vapour pressure deficit, maximum temperature, solar radiation, and soil water storage between 0 and 10 cm. Our model suggested that a J. virginiana woodland with a closed canopy is capable of transpiring almost all precipitation reaching the soil in years with normal precipitation, indicating the potential for encroachment to reduce water yield for streamflow and groundwater recharge. Copyright (C) 2013 John Wiley & Sons, Ltd.

Feedbacks between vegetation and disturbance processes promote long-term persistence of forest-grassland mosaics in south Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Identificação de Plasmodium spp. em primatas neotropicais e em anofelinos em municípios da região de São Luís, estado do Maranhão, Brasil

Pós-graduação em Medicina Veterinária - FCAV

Plantas e formigas em diferentes usos da terra e técnicas de restauração no Cerrado

Pós-graduação em Ciência Florestal - FCA

Diversidade florística e morfoanatômica de comunidades não arbóreas de cerrado sensu stricto frente ao adensamento vegetacional na ausência de fogo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)