900 resultados para Queimas controladas
Resumo:
Fire is a common event in different ecosystems and can both be caused by humans or have natural sources.. In many of these ecosystems, natural fires are an important factor that determines the vegetation. The reduction of tree cover by fire for example, resulted in the evolution of several species-rich ecosystems, dominated by C4 grasses. However, the fire caused by human actions may have greater intensity and lead to negative responses of vegetation, since man changed the fire regime in many parts of the world, such as in the Cerrado. The passage of fire can benefit herbaceous and woody seedlings that cannot compete with the dominant grass layer. It removes the dead biomass and litter (major components of the fuel load), opening up spaces within the grass matrix that allow the establishment of other species. After some time without fire, an increase in shrub cover and decrease herbaceous layer can be observed. One of the major consequences of the absence of fire in savanna and grassland ecosystems is the accumulation of flammable dead biomass (mainly composed of graminoids), which will probably be the fuel load of the next burning thus, fires will be more intense and hotter. Moreover, very frequent burns lead to a reduction in the frequency and density of grasses. Therefore, this study aimed to assess the quantity and quality of biomass in areas with different fire history (fire exclusion for 2 and 7 years) in areas of campo sujo in central Cerrado. Plots (1x1m) were established in both areas and all aboveground biomass of each plot was cut at ground level and put in paper bags in the field. In the laboratory, the material was sorted into live and dead biomass. In addition, live biomass was separated into different functional groups (graminoids, forbs, Vellozia spp, palm and shrubs). The material was oven dried for two days at 80°C and subsequently weighed. In both areas, we found a dominance of graminoid and dead biomass. The area...
Resumo:
The search for new methods of manufacture of glass-ceramics with controlled porosity and permeability is interesting of the industrial and commercial point of view, and a challenge of great complexity. Porous glass-ceramics produced by sintering and crystallization of glasses can find applications, for example, as filters, materials with bactericidal properties, bio-implants, as catalytic and enzymes supports, among others. An alternative and low cost method of ceramic manufacture reaching different levels of porosity, for diverse purposes, is the conformation assisted by addition of starch, known as consolidation with starch. The objective of this project is to study the process of conformation with starch for making porous glass-ceramics from a commercial glass in the system Na2O-CaO-SiO2, whose kinetics of sintering by viscous flow and surface crystallization are known. The method of conformation with starches is innovative for glass-ceramics and its development opens the way for obtaining a new class of materials. We found a possible route for the production of porous compacts of glass particles, from the powder preparation to the removal of starch. It was observed that a glass powder obtained by dry milling in a ball mill with alumina balls for 24 h, afterwards mixed with water in an eccentric ball mill for 2 h, without the addition of a deflocculant, and subsequently mixed with starch also in an eccentric ball mill for 5 min resulted in slurries stable against sedimentation
Resumo:
O transplante de órgãos é um processo em que se transferem tecidos e/ou órgãos sólidos de um doador vivo ou cadavérico para um hospedeiro. A resposta imune aos aloantígenos, antígenos de um membro da mesma espécie, do doador, caracteriza o processo de rejeição de órgãos. As reações de hipersensibilidade são causadas por respostas imunes controladas inadequadamente, como na formação de complexos antígeno-anticorpo circulantes no Lúpus Eritematoso Sistêmico, ou direcionadas ao tecido do paciente, por resposta de anticorpos, como na Febre Reumática Aguda, e por resposta linfocitária, como na Esclerose Múltipla. A terapia farmacológica para transplantes de órgãos e para reações de hipersensibilidade se baseia na utilização de fármacos imunossupressores, como a prednisona, ciclosporina, anticorpos monoclonais, ácido micofenólico e azatioprina. A talidomida, fármaco com propriedades inibidoras da produção de Fator de Necrose Tumoral Alfa em monócitos, atua como imunossupressor e anti-inflamatório, com atividade de interesse para o tratamento destas condições. Nesse contexto, foi sintetizada, purificada e caracterizada a estrutura química de um novo pró-fármaco planejado para atuar com mecanismo duplo de ação a saber: inibição da inosina 5’-monofosfato desidrogenase e da produção do fator de necrose tumoral alfa.
Resumo:
Seizure is a clinical manifestation of abnormal neuronal hyperactivity of the cerebral cortex, presentation clinical varies according to the location and extent of the brain. The classic seizure begins with an inicial period, named prodrome, followed by the aura, the ictus and finally the post-ictus phase. Seizures can be generalized or focal/partial types. Focal seizures with secondary generalization are the most common type in dogs. The seizure can be divided etiologically in intracraneal (idiopathic epilepsy; sintomatic; probably sintomatic epilepsy) and extracraneal disorders. After determining the etiology of seizures and critical analysis of the frequency, severity, and worry they cause to the owner, you should make the decision whether to launch an anticonvulsant drug therapy. Although the ideal is the elimination of seizures, the real goal should be to decrease the frequency and intensity of crises, without affecting the quality of life of patients taking the drugs used side effects acceptable. The veterinary should consider the bioavailability of the drug, contraindications, toxicity, drug interactions, the amount of daily administration, the availability of the owner and the cost of therapy. Seizures can be controlled in about 70- 80% of the dogs and in the majority of the cats when treated with Phenobarbital alone. Addition of a second drug (usually potassium bromide), decreases the number of seizures in more that 50% in about 70-80% of dogs. However, approximately 20-30% of dogs are refractory to this treatment. In these cases, it will be necessary to think in other pharmacological alternatives, like felbamate, gabapentin, levetiracetam, zonisamid, among others. It has been concluded that... (Complete abstract click eletronic access below)
Resumo:
A concentração de dióxido de carbono (CO2) global eleva-se a cada ano, isso deve-se a um desequilíbrio entre as taxas de emissão deste gás por atividades antropogênicas e fontes naturais e a taxa que a biosfera e oceanos o removem da atmosfera. O CO2 é um importante constituinte químico do ambiente, pois este é um gás que aprisiona radiação infravermelha emitida pela superfície da Terra, contribuindo, assim, para a manutenção da temperatura global necessária a vida. As alterações na concentração de CO2 na atmosfera afetam inúmeros animais que dependem que estas estejam altamente controladas para poderem sobreviver. Em abelhas Apis mellifera valores elevados de temperatura ou níveis de CO2 dentro da colméia podem ter efeitos deletérios. Estes insetos são considerados bioindicadores naturais, pois apresentam diferenças fisiológicas conforme as condições do ambiente, sendo utilizadas na avaliação de efeitos a várias substâncias presentes no meio. Atualmente uma das técnicas utilizadas para a avaliação do efeito de estímulos externos é a utilização da marcação da proteína c-Fos através da expressão do gene c-fos, que indicam tanto a existência de atividade celular como também possibilita a identificação de áreas cerebrais determinadas. Esta proteína foi utilizada com o intuído de verificar se concentrações elevadas de gás carbônico são capazes de alterar as funções cerebrais da abelha Apis mellifera, comprometendo sua atividade de orientação e, conseqüentemente seu forrageamento. Marcações positivas à proteína Fos foram observadas nas regiões dos lobos ópticos e ocelos tanto do grupo controle quanto dos grupos Resumo Jacob, C. R. O. 9 expostos ao gás dióxido de carbono para todas as idades coletadas, estes resultados estão relacionados com a...(Resumo completo, clicar acesso eletrônico abaixo)
Resumo:
It is clear today the ever-accelerating search for new fuels that will eventually replace those that will survive in our society, which are fossil fuels. For this reason, a fuel used since the dawn of humanity and much studied since then, considered the generator of clean, renewable energy, can earn more and more space in the power generation sector, which is biomass. We performed two experiments with two different types of biomass, one from the Amazon rainforest and other pine and eucalyptus as waste from the sawmill UNESP Itapeva. In the first experiment, conducted at the Laboratory of Combustion and Propulsion INPE Cachoeira Paulista were conducted three tests in a chimney with a fan creating forced ventilation, where the biomass was burned and deposited on a support beneath the hood. In the second experiment was conducted to analyze the emission of particulate matter using biomass (waste) from the sawmill on the campus of UNESP experimental Itapeva the burning of it in a burner for heating water for a wood oven. In these experiments we used a particle called DATARAM4 sampler that is capable of sampling both outdoors and inside of pipelines, which is the focus of this work. With this equipment it was possible to measure the concentration of particulate matter in all the firings as above, and compare them to levels acceptable in the current law, always trying to analyze the so-called fine particles, which are those with diameters less than 2.5 μm. Using data obtained from the equipment was also possible to evaluate the diametral distribution of particulate matter in question, and verify which phases of the flares in the concentration and the diameters of the particles are the most critical. In this work we concluded that in all firings conducted concentrations of particulate matter were higher than that allowed by the law, and the diameters were found that are more harmful to human health
Resumo:
As influências do exercício físico crônico sobre o tecido ósseo e hematológico de ratos Wistar têm sido investigados na literatura, porém são raros os trabalhos que abordam tais aspectos numa faixa etária mais precoce, na qual os efeitos podem ser benéficos ou até prejudiciais ao desenvolvimento. Assim, os principais objetivos deste estudo foram investigar os efeitos do treinamento físico regular e predominantemente aeróbio sobre aspectos endócrinos e metabólicos, sobre o tecido ósseo e sistema imunológico. Foram utilizados ratos machos, da linhagem Wistar, recém-desmamados (30 dias), mantidos no Biotério do Laboratório de Biodinâmica do Departamento de Educação Física, sob condições controladas (temperatura ambiente controlada de 25ºC e fotoperíodo de 12h claro/12h escuro). Os animais foram distribuídos em dois grupos experimentais: grupo sedentário (GS) e grupo treinado (GT). Os animais treinados foram submetidos a um protocolo de natação, 5 vezes/semana, 1 hora/dia, com carga de 5% em relação ao peso corporal, durante 6 semanas consecutivas, em água com temperatura controlada (32±2ºC). Ao final do período experimental, foram coletadas amostras de sangue para contagem total e diferencial de leucócitos e hematócrito. Após o sacrifício, foram coletadas amostras de soro para dosagem de glicose, proteínas totais, triglicérides, colesterol e amostras do fígado e músculo para a determinação dos teores de glicogênio, e tíbia para determinação do comprimento e área ósseas. Os dados foram apresentados como média ± desvio padrão. Para identificar diferenças estatísticas entre os grupos utilizou-se teste-t de Student para amostras independentes. O nível de significância foi pré-estabelecido em 5%. Pôde-se constatar que o treinamento físico regular realizado ...(Resumo completo clicar acesso eletrônico abaixo)
Aspectos do nicho de regeneração em duas espécies de Gochnatia (Asteraceae) em comunidade de cerrado
Resumo:
Pós-graduação em Biociências - FCLAS
Resumo:
Epilepsy is a chronic disorder that impairs life quality (LQ) and interferes in emotional, personal, social and family relationship aspects. This study evaluated 165 people with epilepsy diagnosis, ranging from 18 to 75 years old (M=41,28; SD= 13,26), by means of the QQV-65 (Life Quality Questionnaire with 65 questions) and investigated the association between the questionnaire scores and the disease features, comparing patients who showed refrectory seizures with patients with partially controled seizures. There was no difference in relation to the two groups regarding the LQ factor. The QQV-65 emotional factor was the most affected in both groups, since the estimated mean z-escore was 51,0±14,4 for Group I and 49,9±14,7 for Group II. Regarding the type of crisis, the analysis of variance (ANOVA) revealed that Health was the only factor in QQV-65 that showed a statistically significant difference between the z-scores (P = 0.024). However, for the frequency of epileptic seizures, except Health (P = 0.185), other factors QQV-65 proved to be related in a statistically significant way (P> 0.05). The research demonstrated that seizure control perception is quite important in the evaluation of life quality in all its aspects (health, body, society, emotion, locus of control, self-concept and cognition).
Resumo:
Pós-graduação em Agronomia (Agricultura) - FCA
Resumo:
Pós-graduação em Agronomia (Ciência do Solo) - FCAV
Resumo:
Pós-graduação em Engenharia Mecânica - FEIS
Resumo:
Pós-graduação em Engenharia Elétrica - FEIS
Resumo:
Pós-graduação em Agronomia (Produção Vegetal) - FCAV
Resumo:
Pós-graduação em Agronomia (Produção Vegetal) - FCAV