DETERMINATION OF THE WOOD DRYING CURVE FOR FIVE SPECIES OF EUCALYPTUS CULTIVATED IN SOUTHERN BRAZIL.

Author(s):  
Huan Pablo de Souza ◽  
José Mateus Wisniewski Gonsalves ◽  
Claudiney do Couto Guimarães ◽  
Angélica Costa Malheiros ◽  
Aline Aparecida Ludvichak ◽  
...  
2006 ◽  
Vol 10 (2) ◽  
pp. 110-115 ◽  
Author(s):  
Eduardo Walker Zettler ◽  
Rosane Machado Scheibe ◽  
Cícero A.G. Dias ◽  
Patrícia Santafé ◽  
Diógenes Santiago Santos ◽  
...  

2004 ◽  
Vol 52 (3-4) ◽  
pp. 183-194 ◽  
Author(s):  
Ricardo Luiz Queiroz ◽  
Frederico Pereira Brandini ◽  
Franciane Maria Pellizzari

The composition and biomass of the microalgal community at the water-column/sediment interface on the continental shelf off Parana State (Brazil) were studied every 2 months during 1999. Samples for cell identification and determination of chlorophyll a were taken from the interface layer and at discrete depths up to 4 m above the sediment. Results showed a community mainly formed by benthic and planktonic diatoms >30 µm, benthic diatoms <30 µm and cyanobacteria. Cell densities were generally higher at the interface layer. Resuspension and sedimentation events seemed to be a paramount factor regulating the composition and biomass of these communities, and affected differently cells of different size classes. Cells >30 µm, which accounted for most of the pigment biomass, were resuspended from the interface after turbulent periods, and may take advantage of calm periods to stay and grow at the interface. Small benthic diatoms were more susceptible to wind-induced turbulence occurring in higher densities in the water column just above the water-sediment interface. A cyanobacterial bloom (Trichodesmiun) was observed at these bottom layers in the spring-summer periods.


Radiocarbon ◽  
2017 ◽  
Vol 59 (1) ◽  
pp. 195-214 ◽  
Author(s):  
Rafael G Milheira ◽  
Kita D Macario ◽  
Ingrid S Chanca ◽  
Eduardo Q Alves

AbstractIn the present work, we assess the chronology of archaeological sites known as earthen mounds, commonly found at the Pampas biome, among the lowlands of Brazil, Uruguay, and Argentina. We focused on the Pontal da Barra settlement, which is a testimony of the long-term occupation of indigenous groups in the swamp and wet environment of Patos Lagoon, southern Brazil. A Bayesian chronological model based on the radiocarbon (14C) dating of 17 samples of fish otolith, 5 charcoal fragments, and 2 bones (human and dog) allowed determination of the beginning of the occupation as well as the occupational synchronism of the different mounds. The nature of the samples allows us to study the local 14C reservoir effect through the comparison between the group of marine and terrestrial samples, deriving a reservoir offset value of 63±53 14C yr for this particular area, indicating a strong freshwater influence in the lagoon system. We estimate the start of human intervention in the landscapes of southern Patos Lagoon to be around 2200 cal BP, with the most intense activity between 1800 and 1200 cal BP.


2012 ◽  
Vol 12 (4) ◽  
pp. 68-73 ◽  
Author(s):  
Matheus Vieira Volcan ◽  
Alinca Peres da Fonseca ◽  
Mário Roberto Chim Figueiredo ◽  
Luís André Sampaio ◽  
Ricardo Berteaux Robaldo

This study evaluated the effect of temperature on growth of Austrolebias nigrofasciatus, an endemic and threatened annual killifish species of the Patos-Mirim lagoon system in Southern Brazil. In order to verify the effect of temperature on initial growth of A. nigrofasciatus, eggs stored in the laboratory were hatched and juveniles reared for eight weeks at 16 and 22 ºC. The standard length of newly hatched fishes was 4.67 ± 0.25 mm and after eight weeks they reached 23.68 ± 3.73 and 22.68 ± 5.36 mm, respectively at 16 and 22 ºC. However, initial growth of fish reared at 22 ºC was faster and they reached sexual dimorphism at an earlier age compared to those reared at 16 ºC. Final length of females reared at 22 ºC was 23.00 ± 2.83 mm, they were significantly larger than those reared at 16 ºC (17.91 ± 2.47 mm). Males were significantly larger than the females at 16 ºC, but there was no difference for growth between sexes of fish reared at 22 ºC. The sex ratios were 1:0.6 and 1:1.1 (M:F) at 16 ºC and 22 ºC, respectively, suggesting temperature determination of phenotypic sex. Considering the results, it appears that juveniles to be developed in captivity should be kept at 22 ºC during the first six weeks of life, thus ensuring a higher growth rate until puberty.


2012 ◽  
Vol 1 (3) ◽  
pp. 54
Author(s):  
Hudson Couto Do Amparo ◽  
Elissa Cavichon ◽  
Cesar Milton Baratto ◽  
Eduardo Cesar Tondo ◽  
Jane Mary Lafayette Neves Gelinski

The rapid increase in the global production of apples has led to improved monitoring and control of toxic substances present in apples and their derivatives. One of these toxic substances is patulin, a mycotoxin and secondary metabolite produced by different fungi species of the genera <em>Penicillium, Aspergillus, Gymnoascus, Paecilomyces</em> and <em>Byssochlamys.</em> This study evaluated patulin levels in juice produced from Fuji apples subjected to different temperature conditions and storage times in southern Brazil. The apples were divided into groups weighing 1 kg and stored at the following temperatures: 0ºC, 5ºC, 6.7ºC, 19.5ºC and 25ºC. Sub-samples of each group were processed to determine their patulin level by HPLC at the following intervals: 0 (control group), 7, 14 and 21 days. After 28 days of storage at all temperatures, the apples could not be analyzed due to their deterioration. The results indicated that at all temperatures; there was variation in the patulin levels. The smallest patulin value was observed in apple juice stored at 19.5°C and 25°C.


RBRH ◽  
2016 ◽  
Vol 21 (3) ◽  
pp. 603-617 ◽  
Author(s):  
Mauricius Marques dos Santos ◽  
Franciane de Almeida Brehm ◽  
Tais Cristina Filippe ◽  
Heloise Garcia Knapik ◽  
Júlio César Rodrigues de Azevedo

ABSTRACT Parabens and triclosan compounds are widely used in pharmaceutical products, personal care, food and various products of daily use. After use, the final destinations of these contaminants are domestic effluents and the environment if not collected or treated. The objective of this study was to evaluate the presence of parabens and triclosan in environments in a subtropical region, more specifically in the metropolitan region of Curitiba (southern Brazil) and possible effects of these compounds in aquatic environments through risk assessment through the use of risk quotient (RQ). Samples were collected in 20 points for 4 campaigns. For the extraction of the compounds we used the extraction technique of solid phase extraction (SPE). The determination of the compounds was using gas chromatography coupled to mass spectrometry (GC-MS). It was observed high concentrations of parabens, especially MeP (up to 2875 ng L–1). Despite high concentrations of parabens, their presence has a low risk to aquatic organisms. Triclosan has been observed at higher concentrations (415 ng L–1), suggesting once again that these environments are impacted by human action. The RQ assessed that triclosan has a high risk for certain groups of organisms.


2006 ◽  
Vol 23 (4) ◽  
pp. 1284-1289 ◽  
Author(s):  
José F. R. Amato ◽  
Cassandra M. Monteiro ◽  
Suzana B. Amato

The present report is part of a larger study on the helminth fauna of Neotropical Cormorants, Phalacrocorax brasilianus (Gmelin, 1789) in Brazil, particularly, in the southernmost State of Rio Grande do Sul. The nematodes which were found loose in the proventriculus/ventriculus or in groups of adults of different ages and of L3 and L4 larval stages, forming eosinophylic granulomas had a prevalence of 100% in 47 Neotropical cormorants from Lago Guaíba, Municipality of Guaíba. The morphology of the labia/interlabia, the distribution pattern of the caudal papillae in males examined under scanning electron microscopy (SEM), and the tips of the spicules allowed determination of the species as Contracaecum rudolphii Hartwich, 1964 sensu lato (s. l.). This is the first record of C. rudolphii in southern Brazil.


2017 ◽  
Vol 63 (Special Issue) ◽  
pp. S53-S58
Author(s):  
Souček Jiří ◽  
Kroulík Milan

Fresh plant material is degraded quickly and very easily. A possibility to avoid its degradation is drying. Drying is an energy-intensive operation and reducing of energy consumption means improving the energy balance and the economy of production. An important indicator of drying efficiency is the relative rate of drying. Curves of the relative drying rate for poplar (Populus nigra L.) wood were determined in an experimental oven. Freshly harvested samples were compared to samples of poplars that were stored between March and December on an outdoor uncovered area. The rate of stored wood drying was higher in comparison with fresh wood under comparable drying conditions. 


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