30 resultados para Interação do sistema madre-painel
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Dengue virus is an important patogen that causes Dengue desease in all world, and belongs to Flavivirus gender. The virus consists of enveloped RNA with a single strand positive sense, 11Kb genome. The RNA is translated into a polyprotein precursor, wich is cleaved into 3 structural proteins (C, prM e E) and 7 non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B e NS5). The NS3 is a multifunctional protein, that besides to promote the polyprotein precursor cleavage, also have NTPase, helicase and RTPase activity. The NS3 needs a hydrophilic segment of 40 residues from the transmembrane NS2B protein (who acts like cofator) to realize this functions. Actually, there's no vacines available on the market, and the treatment are just symptomatic. The tetrapeptide inhibitor Bz-Nle-Lys-Arg-Arg-H (Ki de 5,8-7,0 M) was showed as a potent inhibitor μ for NS3prot in Dengue virus. That is a inteligent alternative to treat the dengue desease. The present work aimed analyse the interactions of the ligand bounded to the activity site to provid a clear and depth vision of that interaction. For this purpouse, it was conducted an in silico study, by using quantum mechanical calculations based on Density Functional Theory (DFT), with Generalized Gradient approximation (GGA) to describe the effects of exchange and correlation. The interaction energy of each amino acid belonging to the binding site to the ligand was calculated the using the method of molecular fragmentation with conjugated caps (MFCC). Besides energy, we calculated the distances, types of molecular interactions and atomic groups involved. The theoretical models used were satisfactory and show a more accurate description when the dielectric constant = 20 ε and 80 was used. The results demonstrate that the interaction energy of the system reached convergence at 13.5 A. Within a radius of 13,5A the most important residues were identified. Met49, Met84 and Asp81 perform interactions of hydrogen with the ligant. The Asp79 and Asp75 residues present high energy of attraction. Arg54, Arg85 and Lys 131 perform hydrogen interactions with the ligand, however, appear in BIRD graph having high repulsion energy with the inhibitor. The data also emphasizes the importance of residue Tyr161 and the involvement of the catalytic triad composed by Asp75, His51 and Ser135
Resumo:
Esta tesis trata de discutir y entender los diversos tipos de redes sociales y formas de interacción social presentes en el sistema penitenciario de Rio Grande do Norte. Nuestro problema se basa en un incremento significativo en las tasas de encarcelamiento y la prisión en Brasil y el mundo en los últimos diez años. Asimismo, la aparición del crimen organizado ya, en cierta medida, el control de las prisiones brasileñas, como el Comando Vermelho (CV) y el Primeiro Comando da Capital (PCC), una consecuencia directa de las terribles condiciones de las prisiones de Brasil y aumento de la violencia y el crimen en nuestro país. Para resolver el problema, se optó por utilizar las categorías de análisis de Michel Foucault (prisión y la disciplina), Pierre Bourdieu (habitus y campo), Ervirng Goffman (institución total, de interacción, de fachada y de equipo) y Mark Granovetter, Ricardo Abramovay e João Peixoto, entre otros, la nueva sociología económica (Redes, nodos y lazos) como principal apoyo. También construyó una revisión histórica de la cárcel en Brasil y Rio Grande do Norte hasta llegar al objeto. Esto, en términos de investigación cualitativa, se sumergió en el mundo de las prisiones Dr. Francisco Nogueira Fernandes, conocido como Penitenciario de Alcaçuz, ubicado en el municipio de Nísia Bosque, Rio Grande do Norte. Penitenciaría del Estado de origen, las casas de Alcaçuz seiscientos cuarenta y tres reclusos, divididos en cinco pabellones, un total de ciento cuarenta y siete células. Mediante la observación sistemática y la entrevista cualitativa s semi-estructurada como las principales fuentes de recopilación de datos, hemos tratado de explicar el universo que acabamos de analizar por las Ciencias Sociales. Nos dimos cuenta de que, para cumplir con la escena nacional, regaliz viola de manera flagrante lo que se denomina en la Constitución de 1988 y LEP (Ley de Ejecución Penal), sin tener en cuenta los derechos de los individuos a una porción de una oración con un mínimo de dignidad. Se ha demostrado que las personas que permean el universo proviene de un ambiente de la prisión, la sociabilidad violenta, sedo también tienen un habitus precario. La prisión, espacio disciplinario y un tipo específico de interacción social marcada por el control, contribuye a la profundización de habitus, pero que muestra que no es también como un espacio cerrado en absoluto, sino un lugar donde penetran las redes y dinámicas muy social. Al mismo tiempo, se encontró que más de la presencia de "grupos organizados" es el espacio en las cárceles para la interacción social y las redes sociales que pasan dentro y fuera de su espacio
Resumo:
Four different sponge species were screened using Ouchterlony agarose gel and immunodiffusion tests to identify cross-reactivity with the polyclonal antibody IgG anti-deglicosilated CvL, a lectin from Cliona varians. Crude extract from the sponge Cinachyrella apion showed cross-reactivity and also a strong haemmaglutinating activity towards human erythrocytes of all ABO groups. Thus, it was submitted to acetone fractionation, IgG anti-deglicosilated CvL Sepharose affinity chromatography, and Fast Protein Liquid Chromatography (FPLC-AKTA) gel filtration on a Superose 6 10 300 column to purify a novel lectin. C. apion lectin (CaL) agglutinated all types of human erythrocytes with preference for papainized type A and O erythrocytes. The haemagglutinating activity is independent of Ca2+, Mg2+ and Mn2+ ions, and it was strongly inhibited by the disaccharide D-lactose, up to a minimum concentration of 6.25 mM. CaL molecular mass determined by FPLC-AKTA gel filtration on a Superose 12 10 300 column and SDS gel electrophoresis was approximately 124 kDa, consisting of eight subunits of 15.5 kDa, assembled by hydrophobic interactions. The lectin was relatively heat- and pH-stable. Leishmania chagasi romastigotes were agglutinated by CaL, indicating that lactose receptors could be presented in this parasite stage. These findings are indicative of the physiological defense roles of CaL and its possible use in the antibiosis of pathogenic protozoa
Resumo:
Sandflies stand out as important vectors of leishmaniasis. The females need to ingest blood meals, enabling them to transmit protozoa of the genus Leishmania, which may give rise to visceral leishmaniasis (VL) or American tegumentary leishmaniasis (ATL), in addition to transmitting other parasites. Leishmaniasis are important infirmities, distributed worldwide, whose infection results from the interaction of reservoir animals, the vector insect, parasitic protozoa and the healthy host. In the state of Rio Grande do Norte (RN), Brazil, these insects are important transmitters of VL, which usually presents in the most serious form. It occurs mainly in metropolitan areas, with the dog as its main reservoir and Lutzomyia longipalpis as the vector. ATL is most present in the highland areas of the state. In addition to hematophagia, engaged in by the females, both sexes need to ingest carbohydrates, which are essential to the sand flies energy requirements and may interfere in the development of Leishmania. The aim of this study was to determine the occurrence and abundance of sand flies in different environments on the farm belonging to the Empresa de Pesquisas Agropecuárias do RN (Institute of Agricultural Research of RN), in the municipality of Parnamirim, in order to relate this occurrence with climatological and biological references and eating habits. Three consecutive monthly collections were carried out with CDC traps in a fragment of the Atlantic Forest, in a residence, on a goat breeding farm and on cashew, dwarf and giant coconut, mango, banana, eucalyptus, acacia and bean plantations. A total of 1241 sandflies from eight species (Lutzomyia evandroi, Lutzomyia longipalpis, Lutzomyia shannoni, Lutzomyia sordellii Lutzomyia walkeri, Lutzomyia wellcomei, Lutzomyia whitmani, and Lutzomyia intermedia) were collected, most in the forest environment. L. longipalpis, the main VL transmitter, was confirmed as a species adapted to anthropic environments, whereas others such as L. wellcomei, the vector of ATL, occurred predominantly in forests. Carbohydrate characterization of the sand flies and plants of the region demonstrated that a number of exotic plants such as hay and eucalyptus may play some role in the adaptation of these species to modified environments. Breeding in laboratory showed a mean biological cycle of 53.5 days from egg to adulthood for L. shannoni and the possibility of diapause behavior in L. wellcomei. This study serves as a source of information that may contribute to the epidemiological vigilance of tegumentary and visceral leishmaniasis in the state, given that it analyzes the bioecology of transmitting species, as well as their potential to adapt to new environments
Resumo:
The freedom of social communication referred to those freedoms exercised under of the media. The journalism is professional activity responsible for factual information, real, pluralistic and of the public interest, directed diffusely to social orientation. The right of the information, characterized as diffuse right or of fruition by uncertain and numerous holders, is subdivided in the right of the inform, inform yourself and right to be informed. The journalists, as occupants of a enlarged spectrum concerning of right of the inform, have responsibility for the information they disseminate, devoir that puts on the basis of the constitutional right to be informed. This duty is divided with journalistic companies, when them realized. In the research, examined the existence of constitutional guarantees the right to be informed. To answer the question, realized research to support bibliographical and documentary. The guaranty is a empirical preoccupation coated with legality, since lends itself effect concretize a right. Traced so a panel of guarantees of institutional imprint, substantive and procedural. Treating of the institutional guarantees the right to information, it would refer to true institutions (as the free press) and may begin subjective rights. In the case of substantial guarantees, we would have access to information, the confidentiality of the fonts and the incensurable feature of journalistic information. A guarantee peculiar would be constitution of bodies responsible for monitoring the quality of the vehicles of communication. Trace it also a panel strict of procedural safeguards, such as public civil action, the security s warrant, and the rights of petition and answer.
Resumo:
This work focalize the institutional and educational evaluation, aiming to investigate the Municipal System Institutional Evaluation Performance of Teresina City Piauí (2001-2005), and to reflect about Institutional System Performance and its contribution to compose a new learning evaluation practice. In this sense, classifies elements about the evaluation practice in two Elementary Education municipal public schools, involving Education Municipal Bureau technicians as managers, pedagogues, teachers and students. Based on the ethnographic studies principles in the educational area, the work employs investigative procedures like document analysis, interviews with groups and individuals and also participator s comments. Intending to comprehend the complexity produced by the institutional and education evaluation processes, the wok reveals the Institutional Evaluation legal and educational political basis and the several positions assumed by the Learning Evaluation, as a classification tool or as a learning enhancement. This work points, as results, to a evaluation culture bipolarity carried out by the Municipal Education System as a explicit control and regulation toll, related to the classification and learning in a interaction process that operates both in the pressure and the reflection, as a culture practice established between excellence of logic and learning. The evaluation history has been construct on the evaluation actions dialectics, joint simultaneously between the Institutional Evaluation Performance and the learning evaluation. The senses, meanings and actions bipolarity is a interaction process product sustained between the institutional evaluation, under the scholar ranking application, and the learning evaluation. In this relativity, the teacher evaluation practice is found, ruled by interesting, thoughts and actions on the school evaluation, allowing a higher security and support to the learning results. Grounded in the researched reality, its possible to say that the teacher s evaluation practice is diversified, with different characteristics, when it is done in the learning search and in the learning intention. In the first case, reflects, rearranges and constructs new actions that lead the student to produce learning. In the second, shows the will, the wish of learning, but is a weak action, producing a not really significant learning and development; as a result, remains the mark approach as a determinant in the student future. The work s hope is to contribute not just to rethink these two evaluations dimensions the institutional and the learning ones but also to organize the school and to improve the pedagogic process
Resumo:
This dissertation presents a new proposal for the Direction of Arrival (DOA) detection problem for more than one signal inciding simultaneously on an antennas array with linear or planar geometry by using intelligent algorithms. The DOA estimator is developed by using techniques of Conventional Beam-forming (CBF), Blind Source Separation (BSS), and the neural estimator MRBF (Modular Structure of Radial Basis Functions). The developed MRBF estimator has its capacity extended due to the interaction with the BSS technique. The BSS makes an estimation of the steering vectors of the multiple plane waves that reach the array in the same frequency, that means, obtains to separate mixed signals without information a priori. The technique developed in this work makes possible to identify the multiple sources directions and to identify and to exclude interference sources
Resumo:
The pumping through progressing cavities system has been more and more employed in the petroleum industry. This occurs because of its capacity of elevation of highly viscous oils or fluids with great concentration of sand or other solid particles. A Progressing Cavity Pump (PCP) consists, basically, of a rotor - a metallic device similar to an eccentric screw, and a stator - a steel tube internally covered by a double helix, which may be rigid or deformable/elastomeric. In general, it is submitted to a combination of well pressure with the pressure generated by the pumping process itself. In elastomeric PCPs, this combined effort compresses the stator and generates, or enlarges, the clearance existing between the rotor and the stator, thus reducing the closing effect between their cavities. Such opening of the sealing region produces what is known as fluid slip or slippage, reducing the efficiency of the PCP pumping system. Therefore, this research aims to develop a transient three-dimensional computational model that, based on single-lobe PCP kinematics, is able to simulate the fluid-structure interaction that occurs in the interior of metallic and elastomeric PCPs. The main goal is to evaluate the dynamic characteristics of PCP s efficiency based on detailed and instantaneous information of velocity, pressure and deformation fields in their interior. To reach these goals (development and use of the model), it was also necessary the development of a methodology for generation of dynamic, mobile and deformable, computational meshes representing fluid and structural regions of a PCP. This additional intermediary step has been characterized as the biggest challenge for the elaboration and running of the computational model due to the complex kinematic and critical geometry of this type of pump (different helix angles between rotor and stator as well as large length scale aspect ratios). The processes of dynamic generation of meshes and of simultaneous evaluation of the deformations suffered by the elastomer are fulfilled through subroutines written in Fortan 90 language that dynamically interact with the CFX/ANSYS fluid dynamic software. Since a structural elastic linear model is employed to evaluate elastomer deformations, it is not necessary to use any CAE package for structural analysis. However, an initial proposal for dynamic simulation using hyperelastic models through ANSYS software is also presented in this research. Validation of the results produced with the present methodology (mesh generation, flow simulation in metallic PCPs and simulation of fluid-structure interaction in elastomeric PCPs) is obtained through comparison with experimental results reported by the literature. It is expected that the development and application of such a computational model may provide better details of the dynamics of the flow within metallic and elastomeric PCPs, so that better control systems may be implemented in the artificial elevation area by PCP
Resumo:
Low voltage solar panels increase the reliability of solar panels due to reduction of in series associations the configurations of photovoltaic cells. The low voltage generation requires DCDC converters devices with high efficiency, enabling raise and regulate the output voltage. This study analyzes the performance of a photovoltaic panel of Solarex, MSX model 77, configured to generate an open circuit voltage of 10.5 V, with load voltage of 8.5 V, with short circuit current of 9 A and a power of 77 W. The solar panel was assembled in the isolated photovoltaic system configuration, with and without energy storage as an interface with a DCDC converter, Booster topology. The converter was designed and fabricated using SMD (Surface Mounted Devices) technology IC (integrated circuit) that regulates its output voltage at 14.2 V, with an efficiency of 87% and providing the load a maximum power of 20.88 W. The system was installed and instrumented for measurement and acquisition of the following data: luminosities, average global radiation (data of INPE Instituto Nacional de Pesquisas Espaciais), solar panel and environment temperatures, solar panel and DC-DC converter output voltages, panel, inverter, and battery charge output currents. The photovoltaic system was initially tested in the laboratory (simulating its functioning in ideal conditions of operation) and then subjected to testing in real field conditions. The panel inclination angle was set at 5.5°, consistent with the latitude of Natal city. Factors such as climatic conditions (simultaneous variations of temperature, solar luminosities and ra diation on the panel), values of load resistance, lower limit of the maximum power required by the load (20.88 W) were predominant factors that panel does not operate with energy efficiency levels greater than 5 to 6%. The average converter efficiency designed in the field test reached 95%
Resumo:
The study of aerodynamic loading variations has many engineering applications, including helicopter rotor blades, wind turbines and turbo machinery. This work uses a Vortex Method to make a lagrangian description of the a twodimensional airfoil/ incident wake vortex interaction. The flow is incompressible, newtonian, homogeneus and the Reynolds Number is 5x105 .The airfoil is a NACA 0018 placed a angle of attack of the 0° and 5°simulates with the Painel Method with a constant density vorticity panels and a generation poit is near the painel. The protector layer is created does not permit vortex inside the body. The vortex Lamb convection is realized with the Euler Method (first order) and Adans-Bashforth (second order). The Random Walk Method is used to simulate the diffusion. The circular wake has 366 vortex all over positive or negative vorticity located at different heights with respect to the airfoil chord. The Lift was calculated based in the algorithm created by Ricci (2002). This simulation uses a ready algorithm vatidated with single body does not have a incident wake. The results are compared with a experimental work The comparasion concludes that the experimental results has a good agrement with this papper
Resumo:
Expanded Bed Adsorption plays an important role in the downstream processing mainly for reducing costs as well as steps besides could handling cells homogenates or fermentation broth. In this work Expanded Bed Adsorption was used to recover and purify whey proteins from coalho cheese manufacture using Streamline DEAE and Streamline SP both ionic resins as well as a hydrophobic resin Streamline Phenyl. A column of 2.6 cm inner diameter with 30 cm in height was coupled to a peristaltic pump. Hydrodynamics study was carried out with the three resins using Tris-HCl buffer in concentration of 30, 50 and 70 mM, with pH ranging from 7.0 to 8.0. In this case, assays of the expansion degree as well as Residence Time Distribution (RTD) were carried out. For the recovery and purification steps, a whey sample of 200 mL, was submitted to a column with 25mL of resin previously equilibrated with Tris/HCl (50 mM, pH 7.0) using a expanded bed. After washing, elution was carried out according the technique used. For ionic adsorption elution was carried out using 100 mL of Tris/HCl (50 mM, pH 7.0 in 1M NaCl). For Hydrophobyc interaction elution was carried out using Tris/HCl (50 mM, pH 7.0). Adsorption runs were carried out using the three resins as well as theirs combination. Results showed that for hydrodynamics studies a linear fit was observed for the three resins with a correlation coefficient (R2) about 0.9. In this case, Streamline Phenyl showed highest expansion degree reaching an expansion degree (H0/H) of 2.2. Bed porosity was of 0.7 when both resins Streamline DEAE and Streamline SP were used with StremLine Phenyl showing the highest bed porosity about 0.75. The number of theorical plates were 109, 41.5 and 17.8 and the axial dipersion coefficient (Daxial) were 0.5, 1.4 and 3.7 x 10-6 m2/s, for Streamline DEAE, Streamline SP and Streamline Phenyl, respectively. Whey proteins were adsorved fastly for the three resins with equilibrium reached in 10 minutes. Breakthrough curves showed that most of proteins stays in flowthrough as well as washing steps with 84, 77 and 96%, for Streamline DEAE, Streamline SP and Streamline Phenyl, respectively. It was observed protein peaks during elution for the three resins used. According to these peaks were identified 6 protein bands that could probably be albumin (69 KDa), lactoferrin (76 KDa), lactoperoxidase (89 KDa), β-lactoglobulin (18,3 KDa) e α-lactoalbumin (14 KDa), as well as the dimer of beta-lactoglobulin. The combined system compound for the elution of Streamline DEAE applied to the Streamline SP showed the best purification of whey proteins, mainly of the α-lactoalbumina
Resumo:
O vasto número de pesquisas sobre produção oral no ensino de Inglês como Língua Estrangeira (ILE) ao redor do mundo (p. ex. LITTLEWOOD, 1981; BROWN; YULE, 1983; BROWN, 1994; UR, 1996; CARTER; MCCARTHY, 1997; BROWN, 1994; 2004; ELLIS, 2008), assim como estudos sobre aspectos cognitivos e de aquisição da produção oral (SWAIN, 1985; 1995; LEVELT, 1989; SWAIN; LAPKIN, 1995; SKEHAN; FOSTER, 1997; 1999; ROBINSON, 2001; BYGATE, 2001; D‟ELY;WEISSHEIMER, 2004; GUARÁ-TAVARES, 2007; WEISSHEIMER, 2007; BERGSLEITHNER, 2009; dentre outros) têm revelado aspectos para um ensino de ILE mais eficaz e motivador. Com a proposta de contribuir para esse avanço, o presente estudo está inserido no paradigma qualiquantitativo de pesquisa no campo da Linguística Aplicada (LA), primordialmente com base nos estudos de Moita Lopes (1996; 2006), para quem a LA está centrada na resolução de problemas de uso da linguagem, cujo foco está na linguagem de natureza processual. O estudo tem como objetivo verificar as percepções de 34 alunos, de quatro turmas distintas de um curso de ILE, em uma escola privada de línguas, acerca de sua produção oral, ao participarem de atividades orais. O corpus da pesquisa foi gerado pelas respostas dos alunos a questionamentos sobre sua produção oral, em duas fases, no início e no meio do curso, além de uma entrevista semiestruturada realizada com dez dos alunos, ao final do curso, com o intuito de verificar suas percepções sobre sua produção oral. As discussões relacionadas à produção oral em sala de aula de ILE têm respaldo teórico nos trabalhos de Littlewood (1981), Brown e Yule (1983), Almeida Filho (1993), Brown (1994), Ur (1996), Carter e McCarthy (1997), Nunan (1999), Brown (2004) e Ellis (2008), que explicam fenômenos que exercem influência na produção oral, tais como afeto, interação, características de atividades orais, dentre outras variáveis em relação a aspectos cognitivos da produção oral analisadas pelos estudos de Swain (1985; 1995), Levelt (1989), Swain e Lapkin (1995), Skehan e Foster (1997; 1999), Robinson (2001) e Bygate (2001). A análise e discussão dos dados tem como base a Gramática Sistêmico-Funcional proposta por Halliday (1985; 1994) e posteriormente desenvolvida por Halliday e Hasan (1989), Halliday e Mathiessen (2004) e Eggins (2004), dentre outros. O foco desta pesquisa são os mecanismos de Apreciação, um dos domínios avaliativos do subsistema de Atitude, que por sua vez, é parte integrante do Sistema de Avaliatividade, desenvolvido por Martin (2000), Martin e Rose (2003) e Martin e White (2005). Para análise das escolhas linguísticas feitas pelos alunos, utilizamos a ferramenta computacional WordSmith Tools 6.0 (SCOTT, 2010), cuja função Wordlist (lista de palavras) foi utilizada na busca pelos tipos de processos, assim como epítetos, entre outras marcas linguísticas mais recorrentes que caracterizassem suas percepções. Os resultados revelam que nas percepções dos alunos acerca de sua produção oral, ao longo das três fases da geração dos dados para a pesquisa, eles gradativamente deixaram de mencionar aspectos afetivos quanto ao desenvolvimento de sua produção oral e passaram a perceber aspectos mais estruturais de composição da língua
Resumo:
This study discusses about the practice of communication in libraries from the appropriation of the resources of web 2.0, particularly social media, establishing from the aspects of mediatization new communication scenarios in their environments. Aims at understanding how in the contemporary society, the libraries, that symbolize traditional space in the search for information and knowledge, modify their contexts through technological resources involved in your scenario, and specifically checks as the process of mediatization is inserted into the communication practices and interaction of libraries, noting the relevance of the ownership of social media, especially twitter and facebook, by the libraries of the Federal University of Rio Grande do Norte - UFRN. Use as methodological procedures, a theoretical approach concerning the conceptual research to investigate issues relating to social media, communication practice, mediatization and network society, and is characterized by being a descriptive exploratory research, of qualitative nature with adoption of the inductive method, using interviews and direct observation, analyzing reconfiguration scenario of university libraries located in UFRN. Thus, with the of the study, expected to be possible to give an overview of how to establish the use of social media in the scenario investigated by checking the new possibilities of communication, outreach services, information dissemination and interaction with user
Resumo:
In this thesis we analyze the effects that the presence of a near gas giant planet can cause in its host star. It has been argued that the star planet interaction can cause changes in the coronal and chromospheric stellar activity. With this in mind, we analyze a sample of 53 extrasolar planets orbiting F, G and K main sequence stars, among them three super-Earths. In this analysis, we look for evidence of changes in the chromospheric activity due to the proximity of the giant planet. We show that, so far, there is not enough evidence to support such a hypothesis. Making use of the same sample and also taking in account available data for the Solar System, we revisit the so-called magnetic Bode s law. This law proposes the existence of a direct relationship between magnetism and rotation. By using estimations for the stellar and planetary magnetic momentM and the angular momentumL, we construct a Blackett s diagram (logL logM). In this diagram is evident that the magnetic Bode s law is valid for both the Solar System and the new planetary systems
Resumo:
The aim of this study is to assess the usability of the Integrated Management System for Academic Activities (SIGAA) for the sensu stricto postgraduate programs at Universidade Federal do Rio Grande do Norte. The study was based on ergonomic criteria proposed by Bastien and Scapin (1993) and the Federal Government s Handbook of Usability (2010). The methodology used was a descriptive data survey involving an online questionnaire, and a sample of 46 system users, composed of coordinators and secretaries from the sensu stricto postgraduate programs. In addition to this procedure, open interviews were held with the users as well as a documental analysis of calls registered by them at the SIGAA between May 2012 and June 2013. Data analysis showed that a number of additional usability criteria need to be implemented, primarily related to ergonomic problems of orientation, error management and workload. Based on the analyses, several changes were proposed that may streamline secretarial activities, as well as provide greater satisfaction and interaction between the SIGAA and its users