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Produção e transporte do camarão-rosa Farfantepenaeus brasiliensis para a pesca amadora: uma alternativa sustentável?
(Universidade Federal de São Carlos, 2012-05-30) Vaz, Luciano Jensen; Verani, José Roberto; https://lattes.cnpq.br/0053232138684810; https://lattes.cnpq.br/6586699572667482
As well as being popular and growing worldwide, sport fisheries are considered an important recreational, economic and social activity that propels a wide production chain and generates employment and income. The major species of marine shrimp used as live bait in the Brazilian coast used as live bait in sport fishing are: white shrimp Litopenaeus schmitti and pink shrimp Farfantepenaeus brasiliensis and Farfantepenaeus paulensis, all of them included in the list of overexploited species. Although the shrimp are caught in estuaries throughout the year, the main period of capture occurs in the summer months. This fact produces significant fluctuations in the catch throughout the year, occurring in situations that greatly reduced catches. In view of these facts, the cultivation of shrimps for bait production could become an important tool for conservation and regulation of the market for live bait. Thus, the studies that comprise this thesis were directed to the production of pink shrimp F. brasiliensis in biofloc system and management studies related to transportation of shrimp as live bait. From the results observed in thesis, it was observed that there is already a well established method for the production of post-larvae of F. brasiliensis this phase is not an obstacle for the production of live bait. Furthermore, the results show that F. brasiliensis has a potential for the cultivation in biofloc system and can be reared in a stocking density of up to 100 shrimp/m² during the nursery stage and in a density of up to 75 shrimp/m² during the grow-out phase. Finally, it was observed that for the transport of F. brasiliensis the water temperature should be between 16 and 19 °C and stocking density should not exceed 3 shrimp / L or (16.5 g / L), the transport is recommended for a maximum of 10 hours to prevent mortality. Therefore, according to all data obtained in this thesis, post-larvae production, cultivation in biofloc system and transportation of F. brasiliensis to be used as live bait proved to be technically viable solutions to meet the needs of sport fisheries.
Mamíferos e a regeneração da palmeira Attalea dubia em uma área de Mata Atlântica na região Sudoeste do Estado de São Paulo, Brasil
(Universidade Federal de São Carlos, 2012-05-30) Meiga, Ana Yoko Ykeuti; Christianini, Alexander Vicente; https://lattes.cnpq.br/2295622727813765; Martins, Karina; http://lattes.cnpq.br/9367637840430435; Beisiegel, Beatriz de Mello
Animals may influence the spatial distribution and survivorship of plants with which they interact. For instance, the Janzen-Connell model predict that the probability of seed and seedling survivorship is reduced around the parental plant because of the intense seed predation and herbivory in this place, which suggests the role of seed dispersal in plant regeneration. The hunting and habitat fragmentation threaten the regeneration of many plant species that depend on large animals to disperse their seeds. In this study I investigated the relationship between seed dispersion, predation and the spatial distribution and survival of seedlings of the palm Attalea dubia in native forest preserved, evaluating the importance of mammals for plant regeneration. In a second part I compared the pre-dispersal seed predation of A. dubia in three habitats: a continuous forest area, a forest fragment and a pasture. This study was undertaken in Parque Estadual Carlos Botelho , and adjacent areas in south-west of São Paulo State. The flowering and fruiting phenology of the palm was observed during a year (October 2010 to November 2011). Focal observations of fruiting palms and cameras traps allowed us to verify which species of mammals included fruits or seeds of A. dubia in the diet. Seed predation and removal experiments combined with the mapping of the spatial distribution of seedling and adult plants were taken to evaluate the importance of mammals in regeneration and test the Janzen-Connell hypothesis. Fruiting of Attalea dubia occurs throughout the year. The mammal species recorded interacting with A. dubia fruits and seeds were: Cebus nigritus, Guerlinguetus ingrami, Philander frenatus and sigmodontineous rodents. Seeds away from the parent palm were more likely to survive than seeds around the parent palm. The spatial distribution seedlings and juveniles also agree with the Janzen-Connell hypothesis. Small mammals removed most seeds to short distances, around 4 meters. Seed predation by rodents was higher in the fragment than in continuous forest and much reduced in the pasture. Predation by invertebrates was reduced in continuous forest and higher in the fragment. There was no compensation of the seed predation: seed predation by invertebrates did not increase in the absence of rodents. Mammals seems to be not essential to the palm regeneration, but they may be important for the spatial distribution of A. dubia. I suggest that the importance of small mammals, such as squirrels, to seed dispersal and plant regeneration of large-seeded plants has been underestimated. Changes in seed predation among habitats may lead to the dominance of some plant species, reducing plant diversity in the long term. The increase in abundance of A. dubia that occurs in highly disturbed areas and edges of fragments can be the result of the lower seed predation in these areas.
Atividade experimental investigativa: construção do termômetro de coluna líquida
(Universidade Federal de São Carlos, 2012-05-30) Oliveira, Cleidson Santiago de; Leodoro, Marcos Pires; https://lattes.cnpq.br/2929842229198829; https://lattes.cnpq.br/0746649625842036
The excessive appreciation of the mathematical formalism and the lack of contextualization of the content has contributed to many students, especially in high school, to feel animosity to Physics and consequently having low records in this discipline. Defended by many researchers and teachers of Physics, the experimental activity consists of an interesting didactic resource to change this situation. However, it is not frequently used in classroom and when it is applied, in general, becomes inserted in a traditional proposal of teaching, using strictly structured guide that serves only for the illustration of the theory, verification of a law or observation of a phenomenon. As a suggested alternative for this situation we have developed a teaching strategy, grounded in Vigotski's social interaction theory and investigative methodology, which is currently defended by several researchers in the field of Science Education and explores the experimental activity in a flexible way under an investigative perspective. It consists of five parts: i. Contextualization; ii. Instigation; iii. Planning; iv. Accomplishment and v. Ending. The proposal has been applied in a high school classroom in a public school of a night class, as part of our teaching activities. To this end, we choose an experiment, commonly found in many Physics textbooks, which is the construction of a rudimentary liquid column thermometer. This experiment allowed us to explore several concepts related to Thermal Physics such as temperature, thermal equilibrium, expansion and thermal conductivity, calibration of thermometers, both analytically and qualitatively. Considering the context in which this proposal was applied, despite many adversities, we can consider that the work achieved its goal in a satisfactory way, especially concerning to the greater involvement of students in the study of Physics. Attached to this work follows a manual in which we discuss some strategies for realization of experimental activities, pointing out the advantages and disadvantages of each one. Additionally we emphasize the proposal based on the physical investigation in order to exploit the phenomenon in a more interesting and meaningful way.
Toxicidade e alterações hematológicas, morfofuncionais, bioquímicas e genéticas em curimbatás, Prochilodus lineatus, (Teleostei, Prochilodontidae) expostos ao fenantreno
(Universidade Federal de São Carlos, 2012-05-30) Martins, Larissa Parreira Alves; Fernandes, Marisa Narciso; https://lattes.cnpq.br/3021357484136942; https://lattes.cnpq.br/0646938087736412
Recent studies have shown that since 1990, there was an abrupt and substantial increase in the concentrations of phenanthrene in the aquatic environment, due mainly to the increase of activities including petroleum derivatives. This study determined the acute toxicity (LC50;96h) of phenanthrene to Prochilodus lineatus and investigated its effects on gills and kidneys of this species when exposed to sublethal concentrations of phenanthrene (corresponding to 1/100 to 1/50 and 1/5 of LC50;96h) for 24 and 96h, using biochemical, morphological, osmo-ionic, hematological and genetics biomarkers. After the experimental periods, blood samples were obtained via caudal punction for analysis of plasma, haematological and genetics variables, and samples of gills and kidneys were collected and fixed for morphological analysis or frozen for biochemical analysis. Phenanthrene can be considered moderately toxic to P. lineatus because the estimated LC50;96h was 1.013 mg L-1. Sublethal exposure to phenanthrene (200μg.L-1; LC50/5), especially after 96 hours, caused significant changes in almost all parameters: morphological, biochemical, genotoxic, osmo-ionic and heamatological. The osmo-ionic changes (increase of osmolality and ion Na+, and no variation of ion Cl-) suggested a osmo-ionic unbalance, which was confirmed by the results observed in the activity of enzymes involved in osmoregulation (NKA and AC) on gills and kidneys (increase of NKA in gills and kidneys, and increase of AC in kidneys), and also by the changes in the number of chloride cells mainly in kidneys, wich showed an increase. Furthermore, histopathological changes were found in the gills and kidneys.The responses of the heamatological variables evidenced an attempt to improve the oxygen uptake by the gills and inflammatory processes caused by the contaminant. In the enzymes of oxidative stress analyzed, both the inhibition in CAT and SOD activities, and the lack of changing in mechanisms of GPx, GSH and GST in the gills of these animals, led to an unbalance between the antioxidants and pro-oxidant levels and then, a lipid peroxidation. In conclusion, the changes observed in these animals (200μg.L-1) can have adverse affects on your health, once there will be an energetic deviation to restore the normal conditions of the organism, to detriment of other functions such as growth and reproduction, besides the possibility of exhaustion occurs in these animals if environment remain contaminated, thereby increasing the risk of disease and thus the mortality in these individuals.
Obtenção e caracterização de hidrolisados enzimáticos de proteínas do farelo de soja
(Universidade Federal de São Carlos, 2012-05-30) Miranda, Liceres Corrêa de; Tardioli, Paulo Waldir; https://lattes.cnpq.br/8312699938281186
Soy protein concentrate (SPC) is used as an ingredient for food and animal feed. It is obtained from defatted soybean meal by extracting sugars and other soluble compounds. The main consequence of the extraction process is removal or inactivation of most anti-nutritional factors of soybean, which makes this product can be used in place of animal proteins in special diets. This work aimed to study the process of protein hydrolysis as an alternative to increase the value of the SPC through the improvement of their nutritional value. Hydrolysis process has been done many years ago with the purpose of improving physico-chemical, organoleptic and nutritional value of food proteins. Enzymatic hydrolysis is the most appropriate when the objective is to improve the nutritional value, because the chemical methods cause many unwanted effects. We studied two commercial alkaline proteases, Alcalase® and Novo-ProD®. Novo-ProD® showed superior activity than Alcalase® in all pH conditions tested. The process conditions that maximized efficiency of the hydrolysis of SPC by Novo-ProD® were: 55°C, pH 9 and enzyme/substrate ratio of 0.5% (enzyme mass / protein mass). The maximum degree of hydrolysis obtained in three hours reaction under these conditions was approximately 15.2% in bench scale and 12.8% in pilot scale. Increasing solid concentration of the reaction medium from 10 to 30%, maximum degree of hydrolysis of 11.2% was obtained in the same conditions. Digestibility trial was conducted with SPC hydrolyzate with 3,3% against SPC unhydrolyzed in adult dogs and turkeys in the initial growth phase. In dogs, hydrolysis increased apparent digestibility of dry matter from 76.5 to 86.2%, crude protein from 83.9 to 90.6% and metabolizable energy increased by approximately 5%. In turkeys, the increase was from 54.6 to 62.9% for dry matter digestibility and 9% increase in metabolizable energy.
Produção de gases de efeito estufa e potencial de geração de créditos de carbono em processos de tratamento de esgoto sanitário
(Universidade Federal de São Carlos, 2012-05-30) Lima, Aline Pereira; Salvador, Nemésio Neves Batista; https://lattes.cnpq.br/9930582531600560; https://lattes.cnpq.br/1014739932428315
The concept of carbon credits came from the awareness of need to reduce greenhouse gas (GHG) emissions in order to combat the worsening of global warming, discussed and formalized in the Kyoto Protocol. Emission of greenhouse gases as methane, nitrous oxide and carbon dioxide is due to several activities, among them the wastewater treatment, both domestic and industrial. This paper presents an estimation of CH4 and N2O production and energy consumption in wastewater treatment systems most used in Brazil, on which mitigation scenarios were applied to show its representation in terms of carbon credits and monetary value. This work was based on the methodologies and procedures of the Intergovernmental Panel on Climate Change - IPCC. The results show that the largest volumes of GHGs are associated with anaerobic treatments, whose emissions may exceed 200 tCO2e/year. Both suggested mitigation proposals (replacement of anaerobic systems by open aerobic processes or introduction of mechanisms for capturing and burning methane in closed reactors) show a similar emission reduction, mostly between 100 and 150 tCO2e/year for attended population of 1000 persons. However, it was found that the credit potential is in the biogas combustion because aeration demands high energy consumption. This ability to generate carbon credits, from Clean Development Mechanism (CDM), can help soften some of the implementation costs of wastewater treatment plants, as well as stimulate its modernization.