396 resultados para Supressão por dexametasona
Resumo:
The following paper attempted to investigate and discuss the possible improvements in the writing of students from the public network in the 6th grade of elementary school. This research was run in the professional master degree In Portuguese Language. Also based upon Genetic Criticism, this study attempting to analyze in which way and in which proportions the alterations done in the texts reveal and perspective capacity in the students as they replace, broad, remove or just move terms in their assignments. We tried to develop our analysis in the pragmatic perspective in which Textual Linguistic is included, investigating the texts and appreciating them as a construction process of meaning. Our theoretical discussion will be based on and socio-interactional conception of language (MARCUSCHI, 2008), as well as in the postulates of Analyze of Discursion (ADAM, 2010, 2008). It has also been used the theoretical assumptions taken from Genetic Criticism which regard the relation between text and genesis, due to the fact that it considers the text and a the result of a construction of progressive elaboration and the writing as an activity of constant movement (DE BIASI, [2000] 2010; GRÉSILLON, 1989; [1990] 2008; [1992] 2002; SALLES, 2008a). To assemble the data in this research we took into consideration the social variables related to the students and the sociocultural context. Nonetheless, this investigation point towards a real classroom situation where we tried to analyze the language functioning in application conditions, thus, giving us authority to describe more precisely the reality we lived in, which provided us with a more attentive look to the observed particularities. This description of the reality appreciated built a path that point to a research of qualitative data approach to which meanings deriving from interpretation were attributed. To conduct this research we resourced to the Action-Research process. The data are comprised of ten personal reports that were created from rewriting assignments, which constitutes a range of twenty texts assessed starting from the linguistic operations acknowledged by Generative Grammar and continued by Lebrave and Grésillon (2009). As result of this analysis, we identified the operation of adding more often than the other ones. The replacement and removal operations display a very close offspring. Nevertheless, the moving operation was scarcely used. These results, besides demonstrating linguistic creativity of the students, revealed that for a text to be seen as “concluded”, the writing student articulates new elaborations through these linguistic operators and that these movements of coming and going, of erasures and amendments contribute significantly for the teacher to approach the relationship the student keeps with his textual and discursive expression, and then, with that, to hold information that eventually provides individual and collective directions in school productions.
Resumo:
Snakebites are a serious public health problem in tropical and subtropical countries and Bothrops genus is responsible for the accidents in Brazil and throughout Latin America (90% of cases). The local effects (pain, edema, hemorrhage and myonecrosis) and systemic (cardiovascular alterations, shock and blood clotting disorders) caused by the venom of Bothrops are due to the numerous protein and non-protein components, which are part of the constitution of the poison. The only form of therapy is scientifically validated antivenom serum therapy which, however, is not effective with respect to local effects produced, risk of immunological reactions, high cost and difficult access in some regions. Thus, the search for new alternatives to serum therapy becomes important, and in this context, many medicinal plants have been highlighted by the popular use as antiophidic. Among these plants, we can mention the species Jatropha mollissima (Euphorbiaceae) which has popular use in traditional medicine as antiophidic, anti-inflammatory, antimicrobial and antipyretic. Therefore, this study aims to evaluate the neutralizing potential of local effects induced by the venom of Bothrops erythromelas and Bothrops jararaca with the aqueous extract of the leaves of J. mollissima. The leaf extracts were prepared by decoction, fractionated (by liquid-liquid partition) and characterized by thin layer chromatography (TLC) and High Performance Liquid Chromatography (HPLC). Antiophidic activity of the extract was evaluated in model of paw edema, peritonitis, bleeding and myotoxicity induced by venoms of B. jararaca and B. erythromelas. In all models, the extract was evaluated by intraperitoneal route at the doses of 50, 100 and 200 mg/kg, administered 30 minutes prior to injection of the venom (pretreatment protocol). Stains suggestive of the presence of flavonoids: apigenin, luteolin, orientin, isoorientin, vitexin and vitexin-2-O-rhamnoside were detected in the extract by co-CCD. By means of HPLC were identified isoorientin, orientin, vitexin and isovitexin. All tested doses of J. mollissima extract reduced the paw edema induced by the venom with intensity similar to dexamethasone. The aqueous extract of J. mollissima leaves on all evaluated doses, inhibited cell migration induced by B. jararaca and B. erythromelas promoting inhibition of recruitment of mononuclear cells and the polymorphonuclear cells. Local bleeding induced by B. jararaca venom was significantly inhibited by the extract. Both venoms were inhibited by the extract in myotoxic activity. These results indicate that the aqueous extract of J. mollissima leaves have snakebite potential, particularly with respect to local effects, which may justify the use of this plant in traditional medicine and complementary therapy as anti-venom serum.
Resumo:
Snakebites are a serious public health problem in tropical and subtropical countries and Bothrops genus is responsible for the accidents in Brazil and throughout Latin America (90% of cases). The local effects (pain, edema, hemorrhage and myonecrosis) and systemic (cardiovascular alterations, shock and blood clotting disorders) caused by the venom of Bothrops are due to the numerous protein and non-protein components, which are part of the constitution of the poison. The only form of therapy is scientifically validated antivenom serum therapy which, however, is not effective with respect to local effects produced, risk of immunological reactions, high cost and difficult access in some regions. Thus, the search for new alternatives to serum therapy becomes important, and in this context, many medicinal plants have been highlighted by the popular use as antiophidic. Among these plants, we can mention the species Jatropha mollissima (Euphorbiaceae) which has popular use in traditional medicine as antiophidic, anti-inflammatory, antimicrobial and antipyretic. Therefore, this study aims to evaluate the neutralizing potential of local effects induced by the venom of Bothrops erythromelas and Bothrops jararaca with the aqueous extract of the leaves of J. mollissima. The leaf extracts were prepared by decoction, fractionated (by liquid-liquid partition) and characterized by thin layer chromatography (TLC) and High Performance Liquid Chromatography (HPLC). Antiophidic activity of the extract was evaluated in model of paw edema, peritonitis, bleeding and myotoxicity induced by venoms of B. jararaca and B. erythromelas. In all models, the extract was evaluated by intraperitoneal route at the doses of 50, 100 and 200 mg/kg, administered 30 minutes prior to injection of the venom (pretreatment protocol). Stains suggestive of the presence of flavonoids: apigenin, luteolin, orientin, isoorientin, vitexin and vitexin-2-O-rhamnoside were detected in the extract by co-CCD. By means of HPLC were identified isoorientin, orientin, vitexin and isovitexin. All tested doses of J. mollissima extract reduced the paw edema induced by the venom with intensity similar to dexamethasone. The aqueous extract of J. mollissima leaves on all evaluated doses, inhibited cell migration induced by B. jararaca and B. erythromelas promoting inhibition of recruitment of mononuclear cells and the polymorphonuclear cells. Local bleeding induced by B. jararaca venom was significantly inhibited by the extract. Both venoms were inhibited by the extract in myotoxic activity. These results indicate that the aqueous extract of J. mollissima leaves have snakebite potential, particularly with respect to local effects, which may justify the use of this plant in traditional medicine and complementary therapy as anti-venom serum.
Resumo:
In view of the climate of instability and deep social inequalities, it has been evident in the Brazilian reality, a new way to punish systematic already developed and consolidated in other countries, in which, among other things, the criminality is anticipated only by danger that the individual sports. It appears, therefore, that the theory developed by Günter Jakobs, nominated Criminal Law of the Enemy, became subtly inserted in the Brazilian reality as well as in international relations signed. In this sense, the Brazilian State, in order to carry out the international legal cooperation in the criminal field, signed a mutual assistance agreement with the government of the United States of America. Forward the conclusion of Mutual legal Assistance Treaty (MLAT), the signatory countries voiced a desire to cooperate in order to facilitate the implementation of tasks of the authorities responsible for law enforcement in both countries, comprising research, investigation, prosecution and prevention of crime, said internalized adjustment in the Brazilian legal system by means of Decree No. 3810 of 02 May 2001. Alongside these considerations, the present study aims to analyze the Criminal law of the Enemy today, seeking to find evidence of that theory in the MLAT, international legal cooperation instrument signed between the government of the Federative Republic of Brazil and the government of the United States of America. Moreover, it has the objective to describe its effects on the Brazilian jurisdiction, especially as concerns the relativity and the suppression of human rights. Once done the introit, analysis will be carried out in the first chapter, on the definition and main features of the theory of Criminal Enemy of the law, it is imperative to approach the humanistic aspect that preceded the theory as well as the dealings given to some controversial issues surrounding it, such as the anticipation of the enemy's punishment and the disproportionality of the penalties imposed. In the second chapter will present the conceptual assumptions, historical evolution and the positives aspects, as well as the barriers and the pursuit of effectiveness of international legal cooperation. In the chapter, bedroom effective analysis of specific modality of cooperation will be held, the Mutual legal Assistance Treaty - MLAT in criminal matters, signed between the Federative Republic of Brazil and the United States of America, in which the general aspects will be addressed and the MLAT reflections on the Brazilian jurisdiction, which includes analysis about the relativity or suppression of human rights, future trends and creating stricter laws, followed by the presentation of the seized conclusion on the subject, in which, among other approaches, will be voiced understanding about the unconstitutionality certain service requests that, from these, there is the bad use of the agreed instrument.
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We present the results of electrical resistivity, magnetic susceptibility, specific heat and x-ray absorption spectroscopy measurements in Tb1−xYxRhIn5 (x = 0.00, 0.15, 0.4.0, 0.50 e 0.70) single crystals. Tb1−xYxRhIn5 is an antiferromagnetic AFM compound with ordering temperature TN ≈ 46 K, the higher TN within the RRhIn5 serie (R : rare earth). We evaluate the physical properties evolution and the supression of the AFM state considering doping and Crystalline Electric Field (CEF) effects on magnetic exchange interaction between Tb3+ magnetic ions. CEF acts like a perturbation potential, breaking the (2J + 1) multiplet s degeneracy. Also, we studied linear-polarization-dependent soft x-ray absorption at Tb M4 and M5 edges to validate X-ray Absorption Spectroscopy as a complementary technique in determining the rare earth CEF ground state. Samples were grown by the indium excess flux and the experimental data (magnetic susceptibility and specific heat) were adjusted with a mean field model that takes account magnetic exchange interaction between first neighbors and CEF effects. XAS experiments were carried on Total Electron Yield mode at Laborat´onio Nacional de Luz S´ıncrotron, Campinas. We measured X-ray absorption at Tb M4,5 edges with incident polarized X-ray beam parallel and perpendicular to c-axis (E || c e E ⊥ c). The mean field model simulates the mean behavior of the whole system and, due to many independent parameters, gives a non unique CEF scheme. XAS is site- and elemental- specific technique and gained the scientific community s attention as complementary technique in determining CEF ground state in rare earth based compounds. In this work we wil discuss the non conclusive results of XAS technique in TbRhIn5 compounds.
Resumo:
The classical treatment for congenital toxoplasmosis is based on combination of sulfadiazine and pyrimethamine plus folinic acid. Due to teratogenic effects and bone marrow suppression caused by pyrimethamine, the establishment of new therapeutic targets is indispensable to minimize the undesirable effects and improve the control of the infection. Previous studies demonstrated that enrofloxacin and toltrazuril were able to control the infection triggered by Neospora caninum and Toxoplasma gondii. Therefore, the aim of this present study was evaluate the efficacy of enrofloxacin and toltrazuril in the control of T. gondii proliferation in human trophoblast cells (BeWo lineage) and in human villous explants from third trimester. BeWo cells and villous were treated with several concentrations of enrofloxacin, toltrazuril, sulfadiazine, pyrimethamine or association (sulfadiazine + pyrimethamine) in other to verify their viability by MTT or LDH assay, respectively. Next, BeWo cells were infected with T. gondii RH (2F1 clone) or ME49 strain, whereas villous were infected only with RH strain (2F1 clone), after, both cells and villous were treated or not with the same antibiotics and analyzed to T. gondii intracellular proliferation by beta-galactosidase assay (for RH strain) or blue toluidine staining (for ME49 strain). ELISA was performed in the supernatant to evaluate the cytokine profile. Enrofloxacin and toltrazuril did not change strongly the viability in cells and villous. Furthermore, the drugs decreased the parasite intracellular proliferation regardless T. gondii strain in BeWo cells and villous explants when compared to untreated and infected conditions. In BeWo cells infected by RH, enrofloxacin induced high levels of IL-6 low levels of MIF, while both cytokines were upregulated by enrofloxacin and toltrazuril in BeWo cells infected by ME49 strain. Additionally, in villous explantes, enrofloxacin induced high MIF production. Thus, enrofloxacin and toltrazuril were able to control the parasitism in BeWo cells and villous explants, and probably it occurs by modulation of immune response in these cells or tissues and direct action on parasite, but future experiments are necessary to verify this hypothesis.
Resumo:
Since the creation of supersonic vehicles, during the Second World War, the engineers have given special attention to the interaction between the aerodynamic efforts and the structures of the aircrafts due to a highly destructive phenomenon called flutter in aeronautical panel. Flutter in aeronautical panels is a self-excited aeroelastic phenomenon, which can occurs during supersonic flights due to dynamic instability of inertia, elastic and aerodynamic forces of the system. In the flutter condition, when the critical aerodynamic pressure is reached, the vibration amplitudes of the panel become dynamically unstable and increase exponentially with time, affecting significantly the fatigue life of the existing aeronautical components. Thus, in this paper, the interest is to investigate the possibility of reducing the effects of the supersonic aeroelastic instability of rectangular plates by applying passive constrained viscoelastic layers. The rationale for such study is the fact that as the addition of viscoelastic materials provides decreased vibration amplitudes it becomes important to quantify the suppression of plate flutter coalescence modes that can be obtained. Moreover, despite the fact that much research on the suppression of panel flutter has been carried out by using passive, semi-active and active control techniques, very few of them are adapted to deal with the problem of estimating the flutter speeds of viscoelastic systems, since they must conveniently account for the frequency- and temperature-dependent behavior of the viscoelastic material. In this context, two different model of viscoelastic material are developed and applied to the model of sandwich plate by using finite elements. After the presentation of the theoretical foundations of the methodology, the description of a numerical study on the flutter analysis of a three-layer sandwich plate is addressed.
Resumo:
Ao que se percebe, paradigmas até então vigentes passam a ser considerados singulares e ditatoriais. Em contrapartida, estabelece-se uma nova acepção, cujo norte é o pensar “politicamente correto”. Entendendo a publicidade como um produto sociocultural, essa pesquisa inicialmente é bibliográfica visando à conceituação e análise de questões inerentes ao seu tema. Com este contexto devidamente apreendido, uma análise pragmática do discurso foi realizada em um corpus de anúncios publicitários veiculados entre 2009 e 2014, no meio televisivo brasileiro de formato aberto. Nossa investigação se concentrou nos modos com que os elementos postulados pelo pensamento politicamente correto vêm sendo incorporados ao gênero publicitário em construções de sentido. Pudemos observar uma tendência de repreensão de determinados grupos a conteúdos publicitários que tocam em temáticas muito específicas, com interpretações marcadas por um alto grau de subjetividade; e o que se busca muitas vezes, através de um empoderamento permitido por nosso contexto atual, é mesmo a supressão de determinadas temáticas dentro da comunicação publicitária.
Resumo:
In captive common marmoset groups, the reproductive inhibition observed in subordinate female seems to be a result of olfactory, visual and behavioral cues from the dominant female. However, few studies have examined the relationship among adult males living in the same social group. These studies have shown that reproductive failure among peer males seems to be based on hormonal and behavioral mechanisms. New insights on sexual strategies in primates have been shown using fecal steroids, but so far no information is available for common marmoset males. In the present study, we evaluated the influence of light-dark cycle, age and reproductive condition on the profile of fecal androgens in males living in the same family group. Feces were collected from six fathers and six sons for androgen determination during the light phase of the 24-h cycle for eight days randomly distributed over a 4-week period. Androgen levels were determined by enzyme immunoassay technique. Adult sons showed higher androgen levels (166.97 ± 22.95 ng/g) than fathers (80.69 ± 44.38 ng/g) and juveniles (49.06 ± 23.15 ng/g; P < 0.05). No diurnal variation (P > 0.05) in fecal androgen profile was observed in adults or juveniles. No indication of androgen-mediated social competition between fathers and adult sons was demonstrable. These results provide basic information on fecal androgen profile useful to investigate the socioendocrinology of free-ranging common marmoset males and verify that, in contrast to daughters, the reproductive suppression of sons is not based on physiological inhibition of their gonads
Resumo:
Introdução: São poucos os estudos que em Portugal se dedicaram a explorar constructos como o autocriticismo, autocompaixão, saúde mental e o comprometimento organizacional. São nossos objetivos analisar estas associações na Polícia de Segurança Pública, considerando igualmente a influência de variáveis sociodemográficas e profissionais, bem como realizar análises preditivas que permitam verificar quais são as variáveis preditores do comprometimento organizacional. Metodologia: A amostra é constituída por 188 polícias com idades compreendidas entre os 30 e 56 anos (M = 43,75, DP = 5,66). Os participantes preencheram um protocolo integrante do projeto Organizar Positivamente do Instituto Superior Miguel Torga, composto por um questionário sociodemográfico, a SELFCS (Escala da Autocompaixão), a FSCRS (Escala das Formas do Autocriticismo e Autotranquilização), o MHI-5 (Mental Health Inventory) e o QCO (Questionário do Comprometimento Organizacional). Resultados: Os polícias parecem regular a sua relação com a organização através do comprometimento calculativo. A autocompaixão associa-se positivamente ao comprometimento afetivo, sobressaindo a capacidade de mindfulness. O autocriticismo, na forma eu inadequado - menos corrosivo que a forma eu detestado -, revela uma relação positiva com o comprometimento calculativo, pelo que a permanência na organização pode ser emocionalmente negativa, originar ataques ao eu e diminuir a capacidade afetiva. Porém, a capacidade autotranquilizadora (forma eu tranquilizador do autocriticismo) parece capacitar os polícias para o desenvolvimento de maiores níveis de comprometimento organizacional e afetivo. A idade, a antiguidade e menos habilitações literárias parecem favorecer o comprometimento calculativo. Discussão: A autocompaixão pode contribuir para uma atitude positiva e afetuosa do polícia para com a organização. Assim, através de uma intervenção baseada na autocompaixão e no mindfulness, com impacto positivo no comportamento afetivo e normativo, não só se poderá preservar e promover a saúde e o bem-estar dos polícias, mas também fomentar o empenho organizacional, atenuando os efeitos negativos da profissão policial. Esta abordagem poderá contribuir para os objetivos organizacionais, através da supressão das emoções aversivas, da diminuição da intenção de turnover e abandono da organização. / Introduction: There are few studies in Portugal that have been dedicated to explore constructs such as self-criticism, self-compassion, mental health and organizational commitment. Our goals are to analyze these associations at the Public Safety Police, considering also the influence of sociodemographic and professionals variables, as well as to conduct predictive analyses, in order to verify which variables may predict organizational commitment. Methodology: The sample consisted of 188 police with ages between 30 and 56 years (M = 43.75, SD = 5.66). The participants filled in a protocol from the project Organizar Positivamente, from Instituto Superior Miguel Torga, composed by a sociodemographic questionnaire, the SELFCS (Self-Compassion Scale), the FSCRS (Scale of Forms of Self-Criticism and Self-Reassurance, the MHI-5 (Mental Health Inventory) and the QCO (Organizational Commitment Questionnaire). Results: The police officers appear to regulate their relationship with the organization through calculative commitment. Self-compassion is associated positively to affective commitment, with mindfulness showing to be the most important competence in this professional group. Self-criticism, in its inadequate self form – which is less corrosive than the hated self form - reveals a positive relationship with calculative commitment, which might imply that staying in the organization may be emotionally negative, may provoke attacks against the self and diminish the affective capacity. However, the self reassurance capacity (reassure self form of self-criticism) may enable the police officers to develop higher levels of organizational commitment and affective commitment, as well. Age, seniority and fewer qualifications seem to support the calculative commitment. Discussion: Through self-compassion police officers may experience a positive and warmth attitude towards the organization. Thus, an intervention program based on self-compassion and mindfulness may stimulate affective and normative commitment, not only preserving and promoting health and the well-being of police officers, but also fostering organizational commitment and mitigating negative effects in the police profession. This approach may contribute to organizational goals’ through the suppression of aversive emotions, decreasing turnover and intention to abandon the organization.
Resumo:
Some protected special spaces on behalf of fundamental rights to the environment and the housing at the city of Natal are fragile by facing actions and attempts to suppress and changing (or omission in the implementation) of standards in furtherance of those rights at the local level, which seems to reflect a situation that goes beyond the context of the city. Based on integrated approach of the housing rights and the environment and its protection of special spaces on the field of fundamental rights, the thesis seeks to understand the weaknesses that affect the legal state duty under the realization/implementation of fundamental rights to the environment and housing in cities, focusing on the issues of flexibility of the founding legislation of special spaces to the detriment of the attributes they protected and the lack of implementation of the legal system that allows their effectiveness. So, it looks initially to understand the environment and housing rights and their special protected areas in the brazilian legal system, looking forward the evolution of its legal protection, as well as the weaknesses that emerge in the field of their effectiveness. Analyzing the trajectory of the environment and housing rights and their special protected areas in Natal, considering its standards, attributes, protection indicators, weaknesses and negative evidence within its legal protections and their enforcement by state entity, this thesis proposes to verify the existence of forms to confronting the weaknesses founded in the maintenance of legal protection and its implementation. At this point it discusses the legal basis and safeguard instruments of protection, especially within the juridical field, as part of a (re)discussion about issues of legislative and administrative discretion in the face of objective legal state duty to realization/implementation of fundamental rights in the urban space. With all these issues together the thesis does not ignore the scenario where the dividing line between public and private (economic) are becoming ever more tenuous in the field of state action and where the city stands as a special commodity to the reproduction of real estate, according to the interests of capitalist logic
Resumo:
In captive common marmoset groups, the reproductive inhibition observed in subordinate female seems to be a result of olfactory, visual and behavioral cues from the dominant female. However, few studies have examined the relationship among adult males living in the same social group. These studies have shown that reproductive failure among peer males seems to be based on hormonal and behavioral mechanisms. New insights on sexual strategies in primates have been shown using fecal steroids, but so far no information is available for common marmoset males. In the present study, we evaluated the influence of light-dark cycle, age and reproductive condition on the profile of fecal androgens in males living in the same family group. Feces were collected from six fathers and six sons for androgen determination during the light phase of the 24-h cycle for eight days randomly distributed over a 4-week period. Androgen levels were determined by enzyme immunoassay technique. Adult sons showed higher androgen levels (166.97 ± 22.95 ng/g) than fathers (80.69 ± 44.38 ng/g) and juveniles (49.06 ± 23.15 ng/g; P < 0.05). No diurnal variation (P > 0.05) in fecal androgen profile was observed in adults or juveniles. No indication of androgen-mediated social competition between fathers and adult sons was demonstrable. These results provide basic information on fecal androgen profile useful to investigate the socioendocrinology of free-ranging common marmoset males and verify that, in contrast to daughters, the reproductive suppression of sons is not based on physiological inhibition of their gonads
Resumo:
The use of cover crops is a fundamental strategy to the weed management in Southern Brazil. In highly infested areas, the herbicides use is increasing, which increases the costs of the crops production as well as the environmental contamination. Oat and velvet bean plants havecontrasting characteristics regarding to residues decomposition speed and the capacity to immobilize Nitrogen in the soil, providing distinct results of weeds suppression throughout the time, and therefore, requiring distinct management strategies before, during, and after the corn crop establishment. The general objective of the experiment was to evaluate the environmental dynamics of the herbicide atrazine, the corn grain yield, and the efficiency of the weed control, considering areas with distinct history regarding the use of mulching, levels of straw and rates of atrazine. For this, the experiment was carried out in two parts: in the first part, two trials with the corn crop were established, one using oat and the other using velvet bean as cover crops. The experimental design used for both field trials was randomized complete blocks arrangement with four replications. The factor A was constituted by four levels of straw (0; 0.75x; 1.5x; 3x) and the factor B was constituted by four rates of the herbicide atrazine (0; 2100; 4200; 8400 g a i. ha-1). Soil samples were collected for greenhouse trialsto determine the persistence. Atrazine leaching evaluation was performed by chromatography using samples collected over the soil profile.In the field, the weed density, the fresh and dry weight and the yield of the corn were evaluated. In the greenhouse trials, the main variables evaluated were plant height and injury caused by the herbicide toxicity. In the second part, soils with distinct covering history were sampled, and the mineralization and sorption studies, both with 14C-atrazine, were conducted in the laboratory. The experimental design was randomized complete blocks arrangement with four replications. The results from the field experiment show that the high levels of straw above ground, isolated, were not efficient to control completely the weeds, and that high levels of velvet bean`s straw decreased the corn potential yield. The greenhouse trials showed that high levels of oat straw prevent the scape of atrazine to soil, this effect of oat straw upon the herbicide availability on soil was detected up to 12 days after spraying. The half-life of atrazine sprayed over oat straw varied from 7 to 14 days after spraying, while the half-life of atrazine sprayed over velvet bean varied from 5 to 14 days after spraying. Increasing oat straw levels presents the capacity to reduce the lixiviation of atrazine in the soil profile, however, this effect was not verified when using velvet bean straw, because the herbicide was not detected in the soil profile, at 21 days after spraying. The chromatographic analysis indicate thatthe atrazine concentrates closer to the soil surface regardless of amount of straw, not being detected deeper than 8 cm in the soil. The accumulated mineralization of 14C-arazine sprayed over V. sativa is superior if compared to soils with S. cereale or non-covered soils. The sorption coefficient of atrazine is superior when sprayed over straw than over the soil.
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Distributed generation systems must fulfill standards specifications of current harmonics injected to the grid. In order to satisfy these grid requirements, passive filters are connected between inverter and grid. This work compares the characteristic response of the traditional inductive (L) filter with the inductive-capacitive-inductive (LCL) filter. It is shown that increasing the inductance L leads to a good ripple current suppression around the inverter switching frequency. The LCL filter provides better harmonic attenuation and reduces the filter size. The main drawback is the LCL filter impedance, which is characterized by a typical resonance peak, which must be damped to avoid instability. Passive or active techniques can be used to damp the LCL resonance. To address this issue, this dissertation presents a comparison of current control for PV grid-tied inverters with L filter and LCL filter and also discuss the use of active and passive damping for different regions of resonance frequency. From the mathematical models, a design methodology of the controllers was developed and the dynamic behavior of the system operating in closed loop was investigated. To validate the studies developed during this work, experimental results are presented using a three-phase 5kW experimental platform. The main components and their functions are discussed in this work. Experimental results are given to support the theoretical analysis and to illustrate the performance of grid-connected PV inverter system. It is shown that the resonant frequency of the system, and sampling frequency can be associated in order to calculate a critical frequency, below which is essential to perform the damping of the LCL filter. Also, the experimental results show that the active buffer per virtual resistor, although with a simple development, is effective to damp the resonance of the LCL filter and allow the system to operate stable within predetermined parameters.
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The identification of genotypes for drought tolerance has a great importance in breeding programs. The aim of this study was to characterize genotypes of beans in response to drought tolerance in different reproductive stages through physiologic, agronomic and molecular analysis. The experiment was conducted in greenhouse, using a randomized block design with four replicates; 10 cultivars: ANFC 9, ANFP 110, BRS Esplendor, BRSMG Realce, IPR Siriri, IPR Tangará, IPR Tuiuiu, IPR Uirapuru, IAC Imperador and IAC Milênio under two conditions of irrigation: plants irrigated during their entire life cycle, and plants under irrigation suppression in the reproductive stage (R7) until 16% of field capacity, when the irrigation was restored. In the last four days of stress, the gas exchanges were analyzed, and in the last day of stress was analyzed the percentage of closed stomata in the abaxial surface of the leaves, collected in different times of the day (9h, 12h, 15h and 18h). Additionally, plant samples were collected for the following analysis: fresh and dry mass of leaves, stems and legumes, and proline content in leaves and roots. The plants were harvested at the physiological maturity and the yield components and grain yield were determined. In addition, in order to identify polymorphisms in the sequences of promoters and genes related to drought, seven pairs of primers were tested on the group of genotypes. The drought susceptibility indexes (ISS) ranged from 0.65 to 1.10 in the group of genotypes, which the lowest values observed were for IAC Imperador (0.65) and BRS Esplendor (0.87), indicating the ability of these two genotypes to maintain grain yield under water stress condition. All genotypes showed reduction in yield components under water stress. IAC Imperador (43.4%) and BRS Esplendor (60.6%) had the lowest reductions in productivity and kept about 50% of the stomata closed during all the different times evaluated at last day of irrigation suppression. IAC Imperador showed greater water use efficiency and CO2 assimilation rate under drought stress. IPR Tuiuiú, IPR Tangará and IAC Imperador had the highest proline concentrations in the roots. Under water stress condition, there was a strong positive correlation (0.696) between the percentage of stomata closed with the number of grains per plant (0.696) and the fresh mass of leaves (0.731), the maximum percentage of stomata closed 73.71% in water stress. The accumulation of proline in the root was the character that most contributed to the divergence between the genotypes under water deficit, but not always the genotypes that have accumulated more proline were the most tolerant. The polymorphisms in DNA of coding and promoting sequences of transcription factors studied in this experiment did not discriminate tolerant genotypes from the sensitive ones to water stress.