A test of the utility of DNA barcoding in the radiation of the freshwater stingray genus Potamotrygon (Potamotrygonidae, Myliobatiformes)

DNA barcoding is a recently proposed global standard in taxonomy based on DNA sequences. The two main goals of DNA barcoding methodology are assignment of specimens to a species and discovery of new species. There are two main underlying assumptions: i) reciprocal monophyly of species, and ii) intraspecific divergence is always less than interspecific divergence. Here we present a phylogenetic analysis of the family Potamotrygonidae based on mitochondrial cytochrome c oxidase I gene, sampling 10 out of the 18 to 20 valid species including two non-described species. Potamotrygonidae systematics is still not fully resolved with several still-to-be-described species while some other species are difficult to delimit due to overlap in morphological characters and because of sharing a complex color patterns. Our results suggest that the family passed through a process of rapid speciation and that the species Potamotrygon motoro, P. scobina, and P. orbignyi share haplotypes extensively. Our results suggest that systems of identification of specimens based on DNA sequences, together with morphological and/or ecological characters, can aid taxonomic studies, but delimitation of new species based on threshold values of genetic distances are overly simplistic and misleading.

The interlanguage development in the spanish learning as foreign language in Teletandem under the View of the Complexity Theory

This article presents, under the perspective of Complexity Theory, the characteristics of the learning process of Spanish as a foreign language in Teletandem. Data were collected from two pairs of Portuguese-Spanish interagents, who were engaged in a systematic and regular interaction, based on the tandem principles. It was found that the learning experience is developed with the peculiarities that arise from the context, agents, members and their nuances, which revealed the presence of a shallow space between the systems of native and foreign languages.

Anaerobic-aerobic treatment of swine wastewater in uasb and batch reactors in series

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dynamics of cell and tissue genesis in the male reproductive system of ticks (Acari: Ixodidae) Amblyomma cajennese (Fabricius, 1787) and Amblyomma aureolatum (Pallas, 1772): a comparative analysis

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

Contact parameters in two dimensions for general three-body systems

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

The first frequency of cantilevered bars with geometric effect: a mathematical and experimental evaluation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fishery of the Uçá Crab Ucides Cordatus (Linnaeus, 1763) in a Mangrove Area in Cananéia, State of São Paulo, Brazil: Fishery Performance, Exploitation Patterns and Factors Affecting the Catches

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

Comparação de eficiências do uso de sistemas construídos de áreas alagadas (Constructed Wetland Systems - CWS), tipos ascendente e descendente, para tratamento de efluentes

Water is an essential element for life. The use of this element, to support the community, defines it as water resource. This feature is being misused and degraded by the dumping of highly contaminated effluents. The impoverishment of its quality poses a risk to human consumption. The necessity to manage this resource, treating the wastewater properly, requires the constant improvement of treatment systems. Another need is to adjust the cost of systems to the demands of communities with less financial clout. This study aimed to adapt and understand the systems of wetlands, improving its efficiency, in an attempt to collaborate with the enrichment of this technology. The practical evidence, with lab-scale prototypes, assembled in ETE Piracicamirim with urban sewage effluent contributed to highlight the problems and operating system design. The bibliographic review showed that several studies had effectiveness for treatment. But it was evident the need for better understanding of dimensioning definitions that better attempted to the answers into the project. Moreover, standardization of system conditions for the specific wastewater treatment is an interesting field, identified, for future studies yet contribute to environmental engineering and sanitation

Effect of mixture of diazinon and benzo[a]pyrene in Glutathione S-transferase of Nile tilapia

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

Prenatal exposure to testosterone masculinises the female gerbil and promotes the development of lesions in the prostate (Skene

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

Characterization of the commercial fish production landed at Manaus, Amazonas State, Brazil

The present work aims to update a series of information about the regional fishing production, by presenting and characterizing the contribution of the different sub-systems of the Amazon basin to the catch landed at the main fishing market of Manaus, Brazil, from 1994 to 1996. Collectors specifically hired for this function registered key information on the fisheries. Thirty nine types or groups of fish were found in the fishing production landed. Jaraqui (Semaprochilodus spp.), curimatã (Prochilodus nigricans), pacu (Myleinae), matrinchã (Brycon cephalus), sardine (Triportheus spp.), aracu (Anostomidae) and tambaqui (Colossoma macropomum) were the most important items during three consecutive years. In 1994 these items summed up 91.6% of the total production; in 1995 and 1996 these values were, respectively, 85.3% and 86.4% of the total production. Tambaqui landed decreased remarkably during the period 1976-1996. There was a strong seasonal component in the production of the main species; jaraqui and matrinchã were mostly landed between April and June, while curimatã, pacu, and sardine were mostly landed during the dry season. Other important items showed a strong inter-annual variation in their production. The fishing production landed came mostly from the sub-system of the Purus River (around 30% of the total production). The subsystem of the Medium-Solimões contributed with an average of 15% and the sub-systems of the Madeira, Lower-Solimões, Upper-Amazon and Juruá, together contributed with 11.5% of the total production landed. Finally, the remaining sub-systems contributed with only 7.6% of the production.

Sub-MICs of Mentha piperita essential oil and menthol inhibits AHL mediated quorum sensing and biofilm of Gram-negative bacteria

Bacterial quorum sensing (QS) is a density dependent communication system that regulates the expression of certain genes including production of virulence factors in many pathogens. Bioactive plant extract/compounds inhibiting QS regulated gene expression may be a potential candidate as antipathogenic drug. In this study anti-QS activity of peppermint (Menthe piperita) oil was first tested using the Chromobacterium violaceum CVO26 biosensor. Further, the findings of the present investigation revealed that peppermint oil (PMO) at sub-Minimum Inhibitory Concentrations (sub-MICs) strongly interfered with acyl homoserine lactone (AHL) regulated virulence factors and biofilm formation in Pseudomonas aeruginosa and Aeromonas hydrophila. The result of molecular docking analysis attributed the QS inhibitory activity exhibited by PMO to menthol. Assessment of ability of menthol to interfere with QS systems of various Gram-negative pathogens comprising diverse AHL molecules revealed that it reduced the AHL dependent production of violacein, virulence factors, and biofilm formation indicating broad-spectrum anti-QS activity. Using two Escherichia colt biosensors, MG4/pKDT17 and pEAL08-2, we also confirmed that menthol inhibited both the las and pqs QS systems. Further, findings of the in vivo studies with menthol on nematode model Caenorhabditis elegans showed significantly enhanced survival of the nematode. Our data identified menthol as a novel broad spectrum QS inhibitor.

Construção exata de sólitons de Hopf

Pós-graduação em Física - IFT

Population Growth of Antarctic Fur Seals: Limitation by a Top Predator, The Leopard Seal?

Antarctic fur seals (Arctocephalus gazella) in the South Shetland Islands are recovering from 19th-century exploitation more slowly than the main population at South Georgia. To document demographic changes associated with the recovery in the South Shetlands, we monitored fur seal abundance and reproduction in the vicinity of Elephant Island during austral summers from 1986/1987 through 1994/1995. Total births, mean and variance of birth dates, and average daily mortality rates were estimated from daily live pup counts at North Cove (NC) and North Annex (NA) colonies on Seal Island. Sightings of leopard seals (Hydrurga leptonyx) and incidents of leopard seal predation on fur seal pups were recorded opportunistically during daily fur seal research at both sites. High mortality of fur seal pups, attributed to predation by leopard seals frequently observed at NC, caused pup numbers to decline rapidly between January and March (i.e., prior to weaning) each year and probably caused a long-term decline in the size of that colony. The NA colony, where leopard seals were never observed, increased in size during the study. Pup mortality from causes other than leopard seal predation appeared to be similar at the two sites. The number of pups counted at four locations in the Elephant Island vicinity increased slowly, at an annual rate of 3.8%, compared to rates as high as 11% at other locations in the South Shetland Islands. Several lines of circumstantial evidence are consistent with the hypothesis that leopard seal predators limit the growth of the fur seal population in the Elephant Island area and perhaps in the broader population in the South Shetland Islands. The sustained growth of this fur seal population over many decades rules out certain predator–prey models, allowing inference about the interaction between leopard seals and fur seals even though it is less thoroughly studied than predator–prey systems of terrestrial vertebrates of the northern hemisphere. Top-down forces should be included in hypotheses for future research on the factors shaping the recovery of the fur seal population in the South Shetland Islands.

METHODS OF CONTROLLING COYOTES, BOBCATS, AND FOXES

In reviewing methods of predator control, it would first seem appropriate to define what is meant "by "methods" and what is meant by "control." Taking the last term first, control, as applied to the predatory coyotes, bobcats, and foxes, may be defined as regulating the numbers of these animals to the point where the economic losses for which they are responsible will be reduced to a practicable minimum. In some situations, area control, i.e., limiting the numbers of the offending predator over wide areas, may be necessary for satisfactory reduction of economic losses; in other situations, spot control or localized reduction of numbers of a certain predator may be called for; in still other situations, elimination of an individual animal may be all the control that is needed. In no sense is control, as applied to coyotes, bobcats, and foxes, intended to mean extermi¬nation of a species. The term "methods" is interpreted as meaning the procedures employed against coyotes, bobcats, and foxes, and not the broader systems of predator control such as the paid hunter system, the extension system, or the much-discredited bounty system. For an excellent review of the systems of predator control, see Latham (l).