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Desenvolvimento de métodos eletroanalíticos para a determinação do diuron e ametrina e estudos de sorção em solos sob mata e cana-de-açúcar
(Universidade Federal de São Carlos, 2009-07-29)
Soares, Gabriela Byzynski
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Silva, Wilson Tadeu Lopes da
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https://lattes.cnpq.br/8492938071491133
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https://lattes.cnpq.br/9466363821556466
It is vital to know the mechanisms and processes of interaction between pesticides and the environment and monitor the groundwater, surface water and soil in intensively used areas which such products for the evaluation of the pollution degree of natural resources. Therefore, there is a need for accurate, reliable and affordable methods of analysis. The objective of this work was to develop electroanalytical procedures for the determination of the herbicides diuron and ametryne, for the study of their sorption in soils under sugar cane production and the native forest in the sub-basin of the Ribeirão das Guabirobas, São Carlos and estimate their potential of contamination of surface and groundwater. The soils studied have contrasting granulometric sizes (sandy and clayed) and were characterized chemically and mineralogically by different techniques. Electroanalytical methods were developed for the determination of diuron with composite GPU electrode and ametryne with silver amalgam electrode. The methodologies developed were used to determine the concentrations of the herbicides in the equilibrium in the batch experiments. The sorption coefficients (Kd) obtained for diuron in the four soils tested showed higher influence with the amount of clay and the amount and quality of soil organic matter in sorption process. For ametryne, there was an important influence of pH in the sorption capacity of the herbicide in the soils. The results are in agreement with the data found in the literature using others techniques, such as chromatography and liquid scintillation, allowing to conclude that the developed procedures using the GPU and silver amalgam electrodes are suitable for the determination of sorption isotherms of these herbicides in soils, having the advantages of being simple and less expensive when compared with the conventional methods.
Caracterização ambiental e condição do uso da terra da paisagem do município de São Félix do Araguaia - MT
(Universidade Federal de São Carlos, 2009-07-29)
Alves, Marilene de Moura
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Santos, José Eduardo dos
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https://lattes.cnpq.br/8533387365058570
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https://lattes.cnpq.br/1879840591735269
There is an increase need for remote sensing data and associated analysis techniques in detecting and monitoring landscape change, particularly for resource management and planning. Information derived from remote sensing spatial data landscape has often been used to assist in the formulation of policies and provide insight into land-use patterns. To understanding human disturbance regimes for developing conservation and ecosystem management plan and for targeting ecological areas that define scarce ecosystems services this study has provided a landscape structure digital database at scales of observations that meet various mapping criteria (geology, geomorphology, pedology, hydrography, hypsometry, road net, settlements, legally protected areas and land-use of the São Félix Araguaia municipality. The monitoring current land-use for characterizing anthropogenic and natural surfaces was based on the use of the Systems of Geographical Information and image LandSat 5 TM. The pattern of land-use reflects the outcomes of more than one human process; for instance, cropland, pastureland and settlements expansion. Natural vegetation was the most abundant land use type, occupying 63.20% of the municipal district total area. Following forest, crop was the next most abundant land use type with 34.75% of the total area. The urban area value is incipient (0.76% of the total area), evidencing that the landscape changes are not influenced by the urban growth. In spite of the amount of forested areas in the municipality is important to point out that many of them are fragmented, isolated, or very close to areas in that the agriculture is the predominant activity. Regional and municipal planners require up-to-date information related to a digital database to effectively manage land development and plan for change.
Prospecção de marcadores microssatélites em Litopenaeus vannamei e análise da diversidade genética em duas famílias de referência de camarões cultivados
(Universidade Federal de São Carlos, 2009-07-29)
Marques, Carla Guinart
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Freitas, Patrícia Domingues de
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https://lattes.cnpq.br/5052695259738538
Avaliação do padrão eletromiográfico dos músculos da mastigação em indivíduos com e sem DTM
(Universidade Federal de São Carlos, 2009-07-29)
Gonzalez, Tabajara de Oliveira
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Bérzin, Fausto
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https://lattes.cnpq.br/5456151579128999
Eletromyographic evaluation of the chewing muscles is amply used in accompaniment of patients with temporomandibular disorders (TMD) with purpose of identifying EMG variations between symptomatic and asymptomatic individuals. However, they re missing studies that deal with parameters of Eletromiographic sign which are able to differentiate individuals with TMD from asymptomatic ones. To contribute to the function of Eletromyographic sign at the differentiation of individuals that present TMD signs and symptoms and asymptomatic ones, two studies were developed. The first study had as objective to categorize individuals with or without TMD signs and symptoms through the Fonseca s Anamnesis Index and to relate this classification to the age, stature, corporal weight and to the RMS values of Eletromyographic sign of masseters and anterior temporalis muscles at rest. 33 female volunteers were selected with the age of 17 to 23 (20,73 ± 1,20), evaluated by Fonseca s Anamnesis Index and divided in two groups: one of them without TMD signs and symptoms (s/TMD) consisting of 16 volunteers and the other group classified as TMD by the referred questionnaire, consisting of 17 volunteers. All these volunteers were submitted to the Eletromyographic evaluation of masseter and anterior temporalis muscles in both sides during the postural position at rest. They were weighted, measured the statures and noted the ages. Among the volunteers of the TMD group, there is a higher prevalence of a light degree TMD, there isn t a relation between the RMS averages of EMG of the studied muscles and a classification of the individuals by the Fonseca Index, the volunteers of TMD group presented higher prevalence of pain, chewed muscles tiredness, articulate noise and habit of grind or press teeth; only the corporal weight presents positive relation with the TMD severity. The second study had as objective to analyze the variability of Eletromyographic signs collected at rest, in bilateral isotonic chewing and in isometric of masseter and anterior temporalis muscles, to evaluate the electric activity of the muscles studied by the Asymmetric Index proposed by literature and to suggest a rate calculation between temporal electric activity in relation to masseter one, in attempt to differentiate the TMD individuals from s/TMD. Eletromiographic signs were collected when jaws at rest, bilateral isometric and bilateral isotonic chewing of the same 33 volunteers that participated in the first study, divided in TMD and s/TMD groups. It was analyzed the variability of the collected signs and applied the Asymmetric Index proposed by literature, besides the rate between temporal muscles and masseter suggested by the authors, in both groups studied. Individuals of TMD group presented a higher variability at EMG of the muscles studied in three collects realized, but it was only observed a significant difference in a collect at the postural position at rest (p≤0,05); only the rate calculation between the RMS values of temporal muscles and masseters, proposed in this study, was able to differentiate individuals with TMD from the asymptomatic ones (p≤0,0001), so this could be a future alternative at differentiation of individuals with or without TMD.
Personalização para televisão digital utilizando a estratégia de sistema de recomendação para ambientes multiusuário
(Universidade Federal de São Carlos, 2009-07-29)
Lucas, Adriano dos Santos
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Zorzo, Sérgio Donizetti
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https://lattes.cnpq.br/2523715806470871
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https://lattes.cnpq.br/3103478732318040
The Digital Television system (TVD) increases the content offer, the audio and video quality and the possibility of services and applications when compared to traditional systems. Among the possibilities of application for this technology, we can highlight the systems able to perform recommendations of content according to the viewer s interests, theses systems are called recommendation systems. Besides offering a different personalization service, the recommendation systems can be a solution to the information overload caused by offering possible content, what makes difficult the search and localization of programs according to the viewer`s interest. Multiuser environment must be taken into account when offering the TVD viewer content personalization, that is, many viewers using the same receptor. This dissertation presents a recommendation system for multiuser environments, the RePTVD (Personalized Recommendation for Digital Television), with its architecture in the Set-top Box. The RePTVD aims at recommending content according to the behavior standards implicitly found when using the television. Therefore, information was implicitly collected and stored, data mining was performed using Apriori algorithm and finally information was filtered. A composition of theses stages was presented using a recommendation process which approaches all the necessary steps to perform the content recommendation. Due to the fact that this is a specific language to TVD and aiming the system portability, API Java TV was used to implement the proposal as a concept proof. Besides that, we could note Brazilian-standard characteristics which have Ginga as the middleware responsible for the applications performance. The evaluation was performed through a test in which data provided by IBOPE Brazilian institute was used concerning the viewing behavior from six houses collected during 14 days. The results indicated the efficiency and quality of RePTVD system implementation.
Uma arquitetura de suporte a modelagem de simulações de treinamento baseada na arquitetura HLA (High Level Architecture)
(Universidade Federal de São Carlos, 2009-07-30)
Rocha, Rafaela Vilela da
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Araujo, Regina Borges de
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https://lattes.cnpq.br/8964123297688432
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https://lattes.cnpq.br/1845113331963646
The use of virtual environments, created by the computer, provides the execution of training simulations in a safe environment to investigate human behaviour and response to dangerous situations. However, building generic virtual environment simulations is a challenge to be researched. At present, existing virtual environment simulations are focused on specific applications. They also have their supporting architecture tightly coupled to the application making extensions or modifications difficult and dependent on computing specialists. Thus, it is important that environments that ease the building of these simulations be created. This work aims to specify an architecture to support the development, implementation, management, control and analysis of collaborative virtual environments, in conformance with the High Level Architecture, a reference architecture for simulations interoperability and reuse. In this work, simulation construction is driven by non-linear, interactive storytelling and instantiated ontologies. The history and ontologies integration facilitates the creation of different simulations without the need for programmers. The goal of the collaborative virtual environment simulations to be created is training for emergency preparedness and response application domain. However, new application domains can be designed by integrating new ontologies. For the ontologies creation, norms for protection against fire and exercise protocols, in use at São Paulo State, were used along with expert advice by São Carlos fire fighters. An environment for the creation of simulations is being developed as part of this work, as well as the whole process of development and execution of a simulation using our proposed architecture. A use case (fire and explosion occurrence) was devised for simulation instantiation. As the main results of this work a novel architecture was devised for the creation of complex training simulations as well as seven ontologies in the emergency management domain. These can be used as powerful tools for the creation of training simulations for the emergency preparedness and response teams.
Construção e aplicação de um Turbidímetro / Nefelômetro Microcontrolado Portátil
(Universidade Federal de São Carlos, 2009-07-30)
Santos, Vagner Bezerra dos
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Fatibello Filho, Orlando
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https://lattes.cnpq.br/9859737944357808
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https://lattes.cnpq.br/5690211284729828
Development of a portable, simple and inexpensive equipment with adequate sensitivity for turbidimetric and/or nephelometric sequential analyses practically simultaneous is the aim of this study. In fact, in-situ and on-line analysis of chemical substances of interest (analytes) can be accomplished. This is requested mainly in situations in which the place is difficult to access or even in circumstances in which the physical- chemical characteristics of the samples should be unchanged. Thus, the equipment was applied in- situ sulfate determination in lake samples. Analytes of interest such as N-acetylcysteine, captopril and thiamine in pharmaceutical samples and potassium in isotonic beverages were also analyzed with the developed instrumentation. The PMTN (Portable Microcontrolled Turbidimeter Nephelometer) is made of LEDs (Light Emitting Diodes) as radiation sources, phototransistors as optical sensors and a PIC microcontroller (Peripherical Interface Controller) as processing unit for control and data acquisition. The PMTN was tested and calibrated properly according to the norms establish by ISO 7027 for equipment base on LEDs as radiation source. The PMTN was applied to determine the concentration of analytes and compared with the reference or validated methods for each analyte, as described in the literature. In general, results agreed at the 95% confidence level were obtained. The detection limits and quantification for the determination of the several analytes were agreed with in some better cases than those found in the literature. On average, the PMTN furnished two decades of linear range of concentration and a reproducibility (RSD) lower than 3.0 % with an average error of less than 5.0 % were also obtained.
Consórcio de exportação de software: pequenas e médias empresas sob a perspectiva de redes sociais
(Universidade Federal de São Carlos, 2009-07-30)
Zacharias, Ana Paula de Lacerda
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Côrtes, Mauro Rocha
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https://lattes.cnpq.br/7474619837965200
This work aims at verifying whether the organization in consortium collaborates to the export insertion of small and medium Brazilian software companies. The verification has been carried out from the social network perspective. It has made use of a qualitative methodology by means of a multi-case study whose target was the Actminds - a software export consortium located in Campinas - SP. For this purpose, social networks analyzing tools and metrics, such as centrality index and degree, have been employed. Results indicate that organization in consortiums is indeed a key factor for the export insertion of the studied companies.
Considerações sobre o projeto, cálculo e detalhamento de vigas pré-fabricadas protendidas com aderência inicial em pavimentos de edificações
(Universidade Federal de São Carlos, 2009-07-30)
Inforsato, Thiago Bindilatti
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Carvalho, Roberto Chust
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https://lattes.cnpq.br/3633394168236221
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https://lattes.cnpq.br/4570430037067936
This work shows a calculation sequence to determine and detail the longitudinal and transverse reinforcement of prestesses beams with pre-composed section. All procedures are done in a way that meets all the requirements of NBR6118: 2003 and 9062:2006 Code. It shows how the checks can be made of the ultimate state limit and the cracking service state and determining whether there is need for the isolation of the strand. The prestesses loss are considered taking into account the age of the constituents of the concrete section at the time when each step is performed and the procedure for progressive loss. The assumptions adopted for the calculation as composite section and the respective transverse reinforcement are detailing. It can be done as the detailing of transverse reinforcement with special care for the end of the piece where it is common the use of dapped-end. Four numerical examples are solved showing how the recommended calculation sequence allows the designer immediately realize the best solution, including the need for the use of prestressed strand along the top edge. The results obtained in the examples it can be seen: the advantage of using the section Ibeam, the semi-rigid connection has a limited efficiency even with large amounts of negative reinforcement, because the existence of the dapped-end, that considering the effect of prestressing causes the shear reinforcement required is minimal. Finally we can conclude that in several instances the situation critical for obtaining the longitudinal reinforcement was in service with the decompression.
Estudo metodológico da reação de Prins em ausência de solventes orgânicos e sua aplicação na síntese de substâncias bioativas
(Universidade Federal de São Carlos, 2009-07-31)
Brito Júnior, Gilmar Araújo
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Santos, Alcindo Aparecido dos
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https://lattes.cnpq.br/9005233120921421
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https://lattes.cnpq.br/8904412440244044
In this work it was done a methodological study on Prins cyclization reaction in the absence of organic solvents. The synthesis of target compounds was possible by using or the catalytic system pTSA.SiO2(gel) initially developed in this project, as shown in Figure I. As a initial proposal of this work, another catalytics systems were developed, this time using non-protonic Lewis acids. The catalytic system FeCl3.SiO2(aerosil) was shown to be the most advantageous among other catalytic systems developed in parallel experiments. The synthesis of target compounds FLOROL ® (6) and CLARYCET ® (8), in absence of organic solvents, was possible by using this catalytic system. The same catalytic system was employed to the preparation of the skeleton of the compound (+/-)- Diospongin A (Figure II). The developed catalytics systems showed to be effective on the catalysis of Prins cyclization reactions involving oxigenate compounds. But these systems had failed when homoallylics amines were employed and so it XII was not possible to obtain the compounds SS20846 A and pipecolic acid, as shown in Figure III.
Degradação bacteriana da MOD excretada por Microcystis aeruginosa (Cyanobacteria) em culturas, fracionada e submetida à radiação UV
(Universidade Federal de São Carlos, 2009-07-31)
Moreira, Ingritt Caroline
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Vieira, Armando Augusto Henriques
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https://lattes.cnpq.br/4428377384377272
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https://lattes.cnpq.br/5616615150766784
Solar radiation can change DOM in aquatic environments making compounds more labile or recalcitrant to biodegradation. Thus, solar radiation, especially UV, indirectly interfere in the microbial community in order to increase or decrease their growth. The objective was to verify the interference of UV-A + B on the bioavailability of DOM separated into different fractions (molecular weight), from release of cells in stationary phase of M. aeruginosa. DOM released from cyanobacteria was separated by tangential ultra-filtration and these were inoculated bacterial community of Barra Bonita reservoir. Bacterial community dynamic was monitored by measures of density and biomass and bacterial consumption of carbon from DOM by measures of DOC. Frequency of bacterial morphotypes were also calculated. All three fractions of DOM investigated were highly available to the bacterial community. The fraction of cultures with DOM<3 kDa and DOM>30 kDa demonstrated to be more vulnerable to UV radiation, corroborated by many statistical differences found for bacterial density during 27 days of incubation. At 15 days of incubation, the cultures with irradiated DOM>30 kDa showed a second peak in bacterial density and biomass that can be understood as an event of succession in bacterial community. Changes in relative frequency of bacterial morphotypes over incubation period suggest an episode of succession during the different stages of degradation of DOM. It was suggested that the majority of DOC released from a bloom of cyanobacteria is rapidly mineralized. Furthermore, the constant blooms, or ever high biomass of M. aeruginosa during the year, mean that such bacterial consortia are always available.
Expressão da Miostatina e ActRIIB em ratos submetidos a dieta hiperlipídica e exercício
(Universidade Federal de São Carlos, 2009-07-31)
Bueno, Patricia de Godoy
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Leal, Ângela Merice de Oliveira
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https://lattes.cnpq.br/7202663545989206
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https://lattes.cnpq.br/7830740384839811
Myostatin (MSTN) is a secreted growth factor expressed in skeletal muscle and negatively regulates skeletal muscle mass. MSTN is also expressed in adipose tissue. Recent data suggest that MSTN regulates adipogenesis and energy metabolism. Aims: The objective of this study was to determine the influence of exercise in the expression of myostatin (MSTN) and its receptor in fat and muscle in obese and insulin resistant rats. Methods: Adult male Wistar rats were housed under controlled conditions (20-220 C, 10-14h light-dark cycle) and were allowed free access to standard rodent chow (control group, CG) or HF diet (58% Kcal from fat, high-fat group, HG) during 12 weeks. Glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed before and at 3, 4, 8 and 12 weeks after diet regimen. After 12 weeks, CG and HG rats were randomly assigned to a swimming training group (CGE and HGE) or a sedentary group (CGS and HGS). CGE and HE swam individually in water tanks (50x30cm) at 340 C, for 45 minutes at 0900h and 1700h, 5 day week-1, for 4 weeks. After this period, rats were submitted again to GTT and ITT and then killed by decapitation. GTT area under the curve was lower in HE compared to HGS. White gastrocnemius muscle and fat pads were dissected, weighted, immediately cooled in liquid nitrogen and stored at - 700 C for subsequent analysis. The mRNA levels were quantified by real time RT-PCR. The animals were maintained according to the local University Committee guidelines for the care and use of laboratory animals. Results: HG developed insulin resistance according to GTT and ITT tests. Adipose fat pads (epididymal, retropritoneal and mesenteric) were 2 to 3 times heavier in high-fat fed groups (HGS and HGE) compared to standard chow fed groups (CGS and CGE). In HGS, the expression of MSTN was significantly higher in mesenteric fat and lower in epididymal fat and Brown tissue adipose (BAT) compared to CGS rats. The expression of ActRIIB significantly decreased in epididymal fat and BAT. The training resulted in decreased of expression of expression of MSTN in muscle and mesenteric fat and increased expression in BAT of CGE compared CGS. The expression of ActRIIB increased significantly in mesenteric fat and BAT in CGE compared to CGS. The expression of MSTN decreased in mesenteric fat and increased in epididymal fat and BAT in HGE compared to HGS. The expression of ActRIIB decreased in muscle and mesenteric fat and increased in BAT in HGE compared to HGS. Conclusions: These data suggest that the expression of MSTN in fat tissues may be involved in the metabolic response of rats submitted to high fat diet and exercise.
Evolução molecular dos genes doublesex e fruitless em moscas-das-frutas do grupo Anastrepha fraterculus (Diptera, Tephritidae)
(Universidade Federal de São Carlos, 2009-07-31)
Júnior Sobrinho, Iderval da Silva
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Brito, Reinaldo Alves de
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https://lattes.cnpq.br/8253066295947754
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https://lattes.cnpq.br/2185153625996785
Species of the Anastrepha fraterculus group are one of the most important agricultural pest from South America and form a group of closely related species whose identification is very difficult. It is problematic to establish reciprocal monophyly of species from this group, because of the great variability and superimposition of morphological traits used in their identification. Many evidences suggest that sex-related genes would be good candidates to discriminate species with low divergence, because they could be involved in the speciation of such species and show high level of differentiation rate. Most of such studies are on genes related to male-female interaction, however few are focused on sex-differentiation genes. We originally aimed to study the role of two sex-determination genes, doublesex (dsx) and fruitless (fru), in the differentiation of the species of Anastrepha fraterculus complex. We also studied the molecular evolutionary pattern of these genes, from high divergence interspecific to low divergence intraspecific data. In the process we assessed the hability of different methodologies in detecting signals of particular selective patterns in the studied regions, and tested a new approach to investigate patterns of positive selection using population data. In this new approach we combined in the same analysis synonymous and nonsynonymous mutations frequencies, their position in the haplotype network, and nonsynonymous mutations capacity to change amino acid physicochemical properties. Differently of what was proposed in previous works, both dsx and fru showed distinct signal of positive selection promoting their differentiation. Furthermore, we detected a selective sweep in the fru connecting region of A. obliqua, possibly involved in the split of haplotype network in two groups, with A. obliqua isolated from the other two species. Although both genes are involved in the sex-differentiation cascade, fru established in clearer way the separation, although not yet completely, of A. obliqua from the other two species here studied.
INCA: um serviço de segurança para ambientes de ensino colaborativos
(Universidade Federal de São Carlos, 2009-08-01)
Gualberto, Thiago de Medeiros
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Zorzo, Sérgio Donizetti
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https://lattes.cnpq.br/2523715806470871
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https://lattes.cnpq.br/8420160200967964
Research efforts on e-Learning systems have mainly focused on the provision of learning contents for users, but these efforts have not considered security requirements in the implementation of such systems. However, threats to security may not be neglected, as these applications are usually built using heterogeneous, distributed and open architectures. This feature may make these systems vulnerable to ill-intentioned users. This work presents the INCA (Integrity, Non Repudiation, Confidentiality and Authenticity), a service that provides security through the technology of Web Services and aims at meeting the security requirements of e- Learning environments developed in different architectures and programming languages. The use of web services to provide security in e-Learning environments will complement the features of such environments, not being limited to platforms in which the client system was developed. INCA uses cryptography and digital signature to provide integrity, non-repudiation, confidentiality and authenticity. Through the tests it could be seen that INCA provides security for e-learning environments in a flexible, configurable, scalable and efficient way. The main features of INCA are presented in this work, with their employability in a case study for the upload tool for Sakai and Moodle environments, which were modified so that they could make use of INCA. The contribuition of this work is the case study implementation for the above mentioned environments, since such tool in these systems does not have security services. Such modifications were necessary to evaluate the applicability of the INCA in different environments. The case study shows the proof of concept for the security service presented in this work.
Catalisadores contendo espécies V2O5 ou VO2+ : atividade e seletividade na redução de NO com amônia
(Universidade Federal de São Carlos, 2009-08-03)
Lima Neto, Antonio Vieira
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Urquieta-González, Ernesto Antonio
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https://lattes.cnpq.br/8488215444152608
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http://lattes.cnpq.br/2389975677904655
The selective catalytic reduction of NOx with ammonia is the best technology available today to carry out the abatement of nitrogen oxide emissions in industrial gas effluents. Currently, vanadia-titania catalysts promoted with WO3 or MoO3 are the most active catalysts for the mentioned reaction. They show a very good catalytic stability for a long time. However, vanadia is also active in the oxidation of SO2 (a compound commonly found in industrial effluents) to SO3 this reaction is highly undesirable since SO3 reacts with water present at effluent gas and ammonia, producing sulfuric acid and ammonium sulfates, NH4HSO4 and (NH4)2SO4. The ammonium sulfates can deposit and accumulate themselves on the catalyst surface besides causing pressure drop problems or equipment corrosion. Apart from this, vanadia-titania catalysts are partially sulfated in SO2 presence, they have specific surface area relatively low (in the order of 40 m2/g) and they can show difficulties when they are discarded because vanadia (as well as WO3 and MoO3) is poisonous to the soil and water. Thus, the optimization or search for new catalytic systems for the selective reduction of NOx with ammonia acquires a significative importance. For this reason, the present work was set in the context of technological route of the selective catalytic reduction of NOx with ammonia and it has the objective of investigate the performance of some catalysts and/or supports (zeolites, mesoporous molecular sieves and transition metal oxides) in the reaction in focus. The studied catalysts were prepared through incipient wet impregnation method or by ionic exchange between a support and a VOSO4 solution. Afterwards, the solids were analyzed by a number of characterization techniques and they were tested in the selective catalytic reduction of NOx with ammonia in the presence of oxygen, in a temperature range of 200°C to 500°C. The materials that have shown the best performances in this first test were subjected to stability tests with water and SO2. The results demonstrated that the Si/Al ratio and the molecular sieve structure, as well as the original cation nature to be exchanged, had influence on the catalyst behavior in the face of the reaction in focus. Finally, accordingly to the test battery accomplished in this investigation, one can say that zeolite H-ZSM-5 exchanged with VO2+ ion was the best catalyst to the selective catalytic reduction of NOx with ammonia, in the temperature range of 350°C to 500°C. It was better, in the test conditions, than the V2O5-WO3/TiO2 (similar to a commercial type).
Avaliação da tendência à formação de fase vítrea nas ligas à base de alumínio do sistema Al-Y-Fe
(Universidade Federal de São Carlos, 2009-08-03)
Benavides Filho, Marcos Antonio
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Botta Filho, Walter José
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https://lattes.cnpq.br/8956458007749112
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https://lattes.cnpq.br/5427230809487223
The present work aimed to study the glass-forming ability of the aluminum-itrium-iron (Al-Y-Fe) alloys. The work included the preparation of samples through the melt-spinning technique and varying the composition of the samples. The structural characterization of the samples was made by x-ray diffraction technique (DRX) and differential scanning calorimetry (DSC). Some complementary characterizations included the Scanning Electron Microscopy (MEV) together with the Energy Dispersion Spectroscopy (EDS). Also were determinated the sample's characteristics temperatures liquidus temperature (Tliq), crystallization temperature (Tx) and glass-transition temperature (Tg). The glass-forming ability of the alloys was discussed based on different approaches from the literature . A discussion about the present glass-forming ability concept is put forward.
Estudo da dispersão de pigmentos orgânicos em resina de polipropileno para aplicação em fibras e filamentos
(Universidade Federal de São Carlos, 2009-08-03)
Dutra, Regiane Defacio
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Bretas, Rosario Elida Suman
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https://lattes.cnpq.br/2805349172281345
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https://lattes.cnpq.br/3954788812913703
Polypropylene has become widely used in fiber and filament applications; most part of these applications use colorful pigments to satisfy aesthetic necessities, communication, identification and others. To achieve the effect of the needed color it is necessary that the pigment has been well dispersed and distribute in the polymer. The appropriate dispersion is usually achieve with the combination of several mechanisms, that can occur at the same time during the mixture operation, such as: initial wetting, size reduction of the pigments, amount of aggregates and agglomerates, intimate wetting, particle uniform distribution in the medium and stabilization of the particles to avoid re-agglomeration. In this work the dispersion of two different organic pigments based on cupper phthalocianine (Pigment Blue 15) and betaoxynaphthoic acid (Pigment Red 48) in polypropylene resin with different humectants systems was studied. The characteristics of each formulation component, the determination of maximum pigment loading in polymer melts based on the CPVC (Critical Pigment Volume Concentration) concept, the ideal conditions of processing in static mixer and co-rotating twin screw extruder and the dispersion were evaluated by tint strength, filter pressure value and scanning electron microscopy. The results showed that there is an optimum humectant for each kind of pigment. The best results were obtained with the red pigment and the oxidized polyethylene wax, in which the filter pressure value was below 2 bar/g. The results for the blue pigment were not satisfactory.
Modelo matemático do processo de purificação do ácido clavulânico por troca iônica em coluna de leito fixo
(Universidade Federal de São Carlos, 2009-08-04)
Cuel, Maressa Fabiano
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Kwong, Wu Hong
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https://lattes.cnpq.br/5750513580197013
Clavulanic acid (CA) is a β-lactam antibiotic produced industrially by submerged cultures of the filamentous bacterium Streptomyces clavuligerus. Due to its importance, several studies on the purification of clavulanic acid have been conducted at the Department of Chemical Engineering of the Federal University of São Carlos DEQ-UFSCar. As a natural sequence of these works, a need has been identified for greater knowledge about the CA adsorption process by mathematically modeling the incorporation of the phenomenon of CA degradation in the sites of resin through a first order reaction. Because amino acids stand out among the principal molecules that are found in fermented broth, it has become imperative for the development of the process to evaluate purification in terms of the amino acids present during the purification process. Some of these amino acids, e.g., tyrosines, present physicochemical properties similar to those of clavulanic acid. The process of batch absorption can be simulated by a mathematical model, providing kinetic and transport parameters involved in absorption. A mathematical model of the clavulanic acid purification process in a fixed-bed absorption column was developed to determine the rupture curve. The modeling allowed for the determination of several important process parameters, such as transport parameters and the intrinsic kinetic constants of absorption. A sensitivity analysis demonstrated that the mass transfer coefficient strongly influences the results of the model. The simulation of the process led to the conclusion that the process is limited both by the degradation stage during absorption and by the mass transfer, indicating that both factors must be taken into account in the analysis of this type of process in a fixed-bed column. It was also found that the degradation of CA in the resin sites is a factor that does not allow the rupture curve to reach the value of C/Co equal to 1, which explains the low yield of the CA process during absorption. This work also aimed to apply the sequencing method to solve the partial differential equations that represent the mathematical model which describes the adsorption of CA in Amberlite IRA-400 resin and to compare it with the finite difference method which is more commonly employed. The application of the proposed methodology in the clavulanic acid purification process in a packed column showed a good performance, with a rupture curve very similar to that obtained by the finite difference method, thus demonstrating the efficiency of the proposed method.
Estrutura genética das populações de abelhas africanizadas (Apis mellifera L.) e suas relações com as raças parentais determinadas por meio da análise de microssatélites
(Universidade Federal de São Carlos, 2009-08-04)
Collet, Thaís
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Del Lama, Marco Antonio
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https://lattes.cnpq.br/7198095288825585
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https://lattes.cnpq.br/3345994967493962
The Africanization process through the Americas started in 1956 with the introduction in Rio Claro (SP) of Apis mellifera scutellata queens from South Africa. The resultant alterations of this process in the characteristics of the preexisting honeybee populations have been measured through several methods, including morphometry, allozymes, mitochondrial DNA patterns and in a lower degree the microsatellite loci. The aim of this study was to determine the genetic structure of the A. mellifera Africanized populations from seven countries of South and Central Americas, employing 12 microsatellite loci. Parental populations from Europe and Africa were used as control. The results obtained from 2034 colonies analyzed indicated that the American Africanized populations presented a high variability and have essentially an African genetic constitution. The South region of Argentina is an exception since those samples keep the variation patterns of the European populations, with a lower degree of polymorphism. However, the presence of Africanized honeybees in high altitudes and low temperatures observed in Colombia indicate that the restrictions for the colonization of temperate regions by the Africanized swarms are not only due to the temperature. Concerning to the low frequencies of the European patterns in the Africanized populations, the contribution of genes characteristics of subspecies from the M lineage (A. m. iberiensis) is higher, with a very low proportion of C lineage genes (A. m. ligustica). Results of population structure indicate that the Africanized populations are genetically low differentiated. Even though a low fraction of European genes exists in the Africanized populations, we can affirm that the genetic constitution of the honeybees of Americas is a straight result of the introduction of A. m. scutellata in Brazil.
Situação atual e perspectivas de utilização de materiais no interior de aeronaves executivas
(Universidade Federal de São Carlos, 2009-08-04)
Costa, Fábio Rodrigues
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Gregolin, José Angelo Rodrigues
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https://lattes.cnpq.br/7842651773105125
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https://lattes.cnpq.br/9160734660960766
This study focuses on analyzing the current situation and perspectives of materials selection and utilization, like composites, decorative laminates and films, and others, in business aircraft, particularly in furnishings and its finishes, of great importance in this sector and systematically few studied. It was used technological prospective and competitive intelligence techniques like interviews with specialists, search in data and patents bases, analysis of existing studies and other sources. A case study was done on finishing materials, which are critical in the business aircraft class. Technological drivers for this sector, like air pollution reduction, personalization and simplicity of utilization, beyond others, were pointed out. It was verified that the materials selection is affected by several factors, namely: market segment involved, flight time and purpose and customer cultural differences, specially in relation to aesthetic, sensitive and comfort requirements; obligation to meet safety requirements from airworthiness agencies, specially in relation to inflammability and structural resistance and cabin safety; need of meeting design requirements, like low weight, high resistance/weight relation, fatigue resistance, degradation resistance, etc. In terms of patenting of cabin, interior and furnishings related technologies, Boeing, Airbus and Bombardier have been in highlighted position, while other business aircraft or interior manufacturers have appeared as owners of a relatively small number of patents. Important companies in key finishes (and their technologies) were identified by patents ownership. It was recommended that the materials selection and procurement process emphasizes the development and capability improvement of potential national suppliers, aiming at meeting business aviation requirements, as well as partnership with the relevant companies in patents ownership. A materials selection methodology was proposed, considering the researched context, which allows the maximization of aggregated value to the customer.