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Cacador, Brazil

Elpino-Campos A.,Federal University of Rio Grande do Sul | Elpino-Campos A.,Contestado University
Acta Ethologica | Year: 2012

Of the 15 species of passion vines recorded for the Rio Grande do Sul State, Brazil, nine are used by Heliconius erato phyllis (Fabricius, 1775). The larvae of this species feed preferentially on Passiflora misera H. B. K., which confers greater performance despite presenting smaller amounts of nutrients than other host plants. Thus, the performance associated with the consumption of a passion vine is possibly related not only to its nutritional content but also to the morphological and behavioral mechanisms involved in the feeding. In this study, the difficulties in accessing food imposed by the hosts (P. misera, Passiflora suberosa L., Passiflora caerulea L., Passiflora edulis Sims, and Passiflora alata Dryand.) were evaluated. Focal observations were performed every 2 min during 6-h sessions (sequential sampling), and the relative time spent for different behaviors (resting, feeding, walking, tasting, and vein cutting) was quantified on both young and old leaves. Larvae devoted more time feeding on P. misera in most cases. Larvae observed on P. alata devoted more to time resting and less time feeding, performing one or two meals of small duration, every 6 h. First instar caterpillars on old leaves of P. suberosa and P. caerulea spent more time walking, searching for a favorable feeding site. The hardness of leaves may be a limiting factor for the initial instars in this heliconian. © 2011 Springer-Verlag and ISPA. Source

Vivan M.,Contestado University | Kunz A.,Pesquisador da Embrapa Suinos e Aves | Stolberg J.,Campus Universitario Of Concordia | Perdomo C.,Campus Universitario Of Concordia | Techio V.H.,Campus Universitario Of Concordia
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2010

Swine production is considered an activity with a high environmental impact, due to the presence of a high number of contaminants in the effluents that come out from the piggery. In this study the feasibility of a combined process biodigestor and stabilization ponds (anaerobic, facultative and maturation) connected in sequence fed with sludge from a swine manure treatment unit was evaluated. The system showed itsetf as efficient in the removal of organic matter, however it presented some limitations in removing nutrients, especially nitrogen, mainly due to the contribution of volatilization of ammonia. Source

Cunha A.,Embrapa Swine and Poultry | Feddern V.,Embrapa Swine and Poultry | De Pra M.C.,Contestado University | Higarashi M.M.,Embrapa Swine and Poultry | And 2 more authors.
Fuel | Year: 2013

This study optimized the conversion of animal fat wastes into ethylic biodiesel by alkali-catalyzed process under mild conditions. A mix of chicken and swine fat residues was used as feedstock for biodiesel production. A full 33 factorial design was used to optimize process parameters for maximum fatty acid ethyl esters yield. Factors were evaluated at three different levels: temperature (30; 50; 70 °C), ethanol:fat molar ratio (6:1; 7:1; 8:1) and catalyst concentration (0.44; 0.88; 1.32 wt.%). Effects of the process variables were analyzed using response surface methodology. Moreover, optimum conditions were applied in a bench-scale reactor and biofuel produced was characterized. It was observed that at high temperatures (50 and 70 °C), phase separation between biodiesel and glycerol was impaired. Although high conversion was achieved (96.2%) at 70 °C, this condition is not recommended because no spontaneous phase separation was verified. On the other hand, 30 °C was identified as the best temperature for biodiesel ethanolysis, using 0.96 wt.% catalyst and 7:1 ethanol:fat molar ratio. With these conditions, it is possible to achieve around 83% conversion. Despite the oxidative stability and total glycerin, biodiesel measured properties agreed with quality requirements established by Official Regulations (ASTM 6751 and EN 14214). © 2012 Elsevier Ltd. All rights reserved. Source

Dal-Cim T.,Federal University of Santa Catarina | Ludka F.K.,Federal University of Santa Catarina | Ludka F.K.,Contestado University | Martins W.C.,Federal University of Santa Catarina | And 5 more authors.
Journal of Neurochemistry | Year: 2013

Guanosine (GUO) is an endogenous modulator of glutamatergic excitotoxicity and has been shown to promote neuroprotection in in vivo and in vitro models of neurotoxicity. This study was designed to understand the neuroprotective mechanism of GUO against oxidative damage promoted by oxygen/glucose deprivation and reoxygenation (OGD). GUO (100 μM) reduced reactive oxygen species production and prevented mitochondrial membrane depolarization induced by OGD. GUO also exhibited anti-inflammatory actions as inhibition of nuclear factor kappa B activation and reduction of inducible nitric oxide synthase induction induced by OGD. These GUO neuroprotective effects were mediated by adenosine A1 receptor, phosphatidylinositol-3 kinase and MAPK/ERK. Furthermore, GUO recovered the impairment of glutamate uptake caused by OGD, an effect that occurred via a Pertussis toxin-sensitive G-protein-coupled signaling, blockade of adenosine A2A receptors (A2AR), but not via A 1 receptor. The modulation of glutamate uptake by GUO also involved MAPK/ERK activation. In conclusion, GUO, by modulating adenosine receptor function and activating MAPK/ERK, affords neuroprotection of hippocampal slices subjected to OGD by a mechanism that implicates the following: (i) prevention of mitochondrial membrane depolarization, (ii) reduction of oxidative stress, (iii) regulation of inflammation by inhibition of nuclear factor kappa B and inducible nitric oxide synthase, and (iv) promoting glutamate uptake. Guanosine (GUO) promotes neuroprotection against oxygen and glucose deprivation in hippocampal slices via a mechanism that involves modulation of adenosine receptors and activation of PI3K/AKT and MAPK/ERK. These signaling pathways are implicated in the prevention of mitochondrial membrane depolarization, reduction of oxidative stress, regulation of inflammation by inhibition of NF-κB and inducible nitric oxide synthase (iNOS), and the promotion of glutamate uptake. EAAT: excitatory amino acid transporter, ROS: reactive oxygen species. Read the Editorial Highlight for this article on doi: 10.1111/jnc.12328. © 2013 International Society for Neurochemistry. Source

It is common the existence of a relation supports between culture and development. It already has many works if dedicated to the subject. In this text the claim had been to contribute in the discussion, rescuing some theoretical origins of the relation between economy, culture and development, present in the different theoretical currents. There is used a synthesis of the theories of the development, from which there are detached the theoretical conceptions that justify such a relation. We conclude that the definition of development, when differentiated from economic growth, and contemplated the notion of structural changes within economic, social, cultural and technological changes, there is not only a relationship between economy, culture and development. The economic dimension and culture are the constituent elements of development processes, along with the social, political, spatial, ecological and technological developments. Source

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