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Distribuição e orientação dos quimiorreceptores de O2 branquiais em tilápia-do-Nilo (Oreochromis niloticus): controle das respostas cardiorrespiratórias à hipóxia
(Universidade Federal de São Carlos, 2012-08-31)
Zeraik, Vivian Maria
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Rantin, Francisco Tadeu
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https://lattes.cnpq.br/3546242299713690
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https://lattes.cnpq.br/8434310797992303
In fish the O2 chemoreceptors are mainly found in the gill arches and monitor the O2 tensions (PO2) of the inspired water (externally oriented) and/or the arterial blood (internally oriented). During hypoxia these receptors trigger cardiorespiratory adjustments in order to maintain an adequate O2 transfer to the tissues. The aim of the present study was to determine the O2 chemoreceptors distribution through the gill arches of Nile tilapia and the role of these receptors on the cardiorespiratory responses to hypoxia in this species. One buccal and two opercular canullae, and a pair of ECG electrodes were implanted in a group of intact fish (control group, n = 10; Wt = 258.4 ± 7.4 g). This procedure served to measure the following cardiorespiratory variables: respiratory frequency - fR, ventilatory tidal volume - VT, gill ventilation - VG , O2 extraction from the ventilatory current EO2, oxygen uptake - VO2 , and heart rate fH. After an overnight recovery period from surgery fish were subjected to the following O2 tensions during 40 min each: 140 (normoxia), 100, 70, 50, 30 e 20 mmHg. To verify the O2 receptors distribution in the gills, the first pair of gill arches was surgically extirpated (operated group, n = 10; Wt = 232.5 ± 8.8 g). After a recovery period of 4 days, operated fish were subjected to the same procedures described above for the intact ones. To examine the orientation of these receptors, other intact (n = 10; Wt = 259.6 ± 6.2 g) and operated (n = 10; Wt = 248.7 ± 6.5 g) groups had a PE catheter implanted into the buccal cavity, another catheter implanted inside the caudal vein and fitted with ECG electrodes to measure the following variables: ventilatory amplitude (Vamp), fR, and fH. Two internal injections (administered through the cannula into the caudal vein): a) 0.5 mL intravenous saline (0.9%), b) 0.5 mL intravenous NaCN (750 μg.mL-1 of NaCN in saline) and two external injections (injected by oral cannula): c) 1 mL H2O, d) 1 mL NaCN (750 μg.mL-1 of NaCN in water) were administered in both groups. The VO2 of operated fish was significantly lower only in severe hypoxia. Both bradycardia, and respiratory parameters were not abolished by ablation of the first pair of gill arches. EO2 of operated group remained about 18% lower than that of control group. The responses to internal and external NaCN included decreases in fH and increases in fR and Vamp. The cardiorespiratory parameters were attenuated in the operated group, indicating the presence of chemoreceptors, but not limited to the first gill arch. In Nile tilapia the O2 chemoreceptors are distributed beyond the first gill arch, probably through the four gill arches. Furthermore, these receptors are internally and externally oriented, possibly along all gill arches, triggering the cardiorespiratory adjustments necessary to face the hypoxic conditions at which the species is frequently subjected in its natural environmental conditions.
Obtenção de inseticida e fungicida contra formigas cortadeiras e seu fungo simbionte em Myracrodruon urundeuva e de complexos de coordenação com metais de compostos ativos para controle desta praga
(Universidade Federal de São Carlos, 2012-08-31)
Sarria, André Lúcio Franceschini
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Fernandes, João Batista
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https://lattes.cnpq.br/2691336077459602
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https://lattes.cnpq.br/9263468171419159
Insects are the major competitors for food in relation to humans. Ants ("sauvas" and "quenquéns") are the major pests of several culture and in reforestation areas in Brazil represent more than 75% of the time and financial expenditure in the control of forest pests and obviously limit the full development of agriculture and forestry. The technology involved in the search for pesticides for the control of pests is in the frontiers of science, which involves different aspects of multidisciplinary and can contribute greatly to the agriculture advancement. One of these aspects is related to natural products, where new molecules isolated from plants can serve as prototypes for new insecticides. The aim of this study was the phytochemical study of Myracrodruon urundeuva in order to search for compounds with insecticidal activity and the synthesis of metal complexes of copper with molecules that present biological activity. The phytochemical study led to the isolation and structural identification/caracterization of 34 secondary metabolites, being seven unique and among them, are the dimeric chalcones, only identified in two species of Anacardiaceae. 31 compounds were synthesized: eight of them have the ligands obtained by Mannich reaction with 2-hydroxy-1,4-naphthoquinone; eight complexes from these ligands; two iminic derived from the flavonoid naringine and naringenine; two complex from these ligands; four complexes of the type Cu(FLAV)2 and seven complexes of the type Cu(X)(FLAV) where X is 2,2´-Bipyridine our 1,10´- Phenanthroline. The extracts of M. urundeuva, isolated compounds and metal complexes were tested in nests of Atta sexdens rubropilosa (test of toxicity by ingestion), enzyme inhibition in AChE and fungicide test in ants symbiotic fungus (Leucoagaricus gongylophorus) withsignificative results.
Arquitetura escalável de alto desempenho para atualização, acesso e recuperação de informações em bancos de dados de aplicações embarcadas
(Universidade Federal de São Carlos, 2012-08-31)
Mezzalira, Daniel
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Trevelin, Luis Carlos
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https://lattes.cnpq.br/5082419783043736
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https://lattes.cnpq.br/7542203427894157
Managing multiple systems such as machine tools, vehicles, aircraft, among others, demand a very intense flow of data between them and the system manager. Researches have been developed in the design and implementation of scalable architectures that meet these demands leading to interesting questions of performance. The objective of this work is to propose a low cost scalable architecture for embedded applications, using pools of personal computers for high performance storage, retrieval and processing of information. It is driven by strong demand for tracking and monitoring of machines and vehicles, covering concepts of mobile networks with satellites and GPRS technology together with the requirement of reliability and performance in the sending of information. Proposes the definition of a server structure, whose distribution is transparent to the application, which is responsible for the receipt of messages from embedded devices via radio frequency technology, decoding and integration of information in the database and subsequent recovery of these information s. Through simulation of different modeled strategies using queuing theory to determine the architecture and the use of predictive mathematical methods for estimating the future burden for the server application, it was possible to obtain a solution that satisfactorily met the assumptions of the research. Thus, it is concluded that it is possible to estimate trends peaks processing information for telemetry applications fleet.
Politecnia e polivalência na organização do trabalho em cooperativas populares e tradicionais
(Universidade Federal de São Carlos, 2012-08-31)
Chiariello, Caio Luis
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Eid, Farid
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https://lattes.cnpq.br/6858881569501075
This PhD thesis contains the theoretical and empirical approach about the work organization on popular and traditional cooperatives in Brazil, presenting the concepts of polytechni and polyvalence within the recent changes in the work scenario. The concept of polyvalence is related to flexible production models, providing greater workers participation in formulation and execution of different tasks. Polyvalent workers have many skills and assume responsibilities, but although polyvalence points to a greater convergence between intellectual and manual labor, it doesn t overcome the gap between execution and management, promoting only the enrichment and expansion of tasks, not questioning capital domination over labor. Therefore, the concept of polytechni proposes an omnilateral worker, refusing the labor technical division under capitalism and arguing that workers might participate fully in the conduction of work process. The incorporation of the knowledge about scientific and technical activities by omnilateral workers approaches 'hand and brain' and inhibits the separation between who manage and who execute the work. Thus, polytechni gives rise to self-management conducted by workers, based on genuine cooperation, searching for the transformation of society in economic, political and social dimensions. The Thesis presents an empirical study in a traditional cooperative - COCAMAR - linked to the agribusiness and applying the polyvalence in their work organization, and four popular cooperatives - COOPAN; COOPERUNIÃO; COPAVI and COPAVA linked to social movements and agrarian reformand and seeking to adhere to the polytechnic principles the selfmanagement. The discussion about the work organization trajectory of the five cooperatives, their internal democracy and power relations, dynamics between management and execution, job rotation and work activities, the working journey, paymente and control and education for the work presents the singularities, approaches and contradictions over the organization of work in these cooperative.
Avaliação de um programa preventivo de violência escolar: planejamento, implantação e eficácia
(Universidade Federal de São Carlos, 2012-08-31)
Pereira, Ana Carina Stelko
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Williams, Lúcia Cavalcanti de Albuquerque
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https://lattes.cnpq.br/6962646759651464
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https://lattes.cnpq.br/4721496386444127
A regulação social do trabalho em sistemas ERP
(Universidade Federal de São Carlos, 2012-09-04)
Ponce, Ana Maria Carlos
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Camarotto, João Alberto
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https://lattes.cnpq.br/1427853773681255
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https://lattes.cnpq.br/2391828882949322
The ERP - Enterprise Resource Planning is considered one of the most important strategies for organizations in a business scenario that reconfigures itself permanently. Most researches on this subject follows a pragmatic-interventionist orientation, predominantly, with an approach oriented to identify practices that could improve the results of ERP implementations for a series of organizational actors and few attentions has been directed to aspects of the regulation of work in the ERP environment. In this perspective, this work aims to verify how the regulation of activity by agents that interact directly with the ERP system occurs. The study was developed with the presupposition of the Theory of Organizational Act of Maggi, on three core issues: the transformation of task, coordination and cooperation. Other issues relevant to the study were addressed as the Ergonomics of the Activity. We performed a qualitative, descriptive research. For the stated purpose it was defined as a technical procedure of research the study of multiple cases. The choice of the companies fell upon those companies that adopted ERP system in the area of Planning and Production Scheduling, in different sectors of activities and that expressed a willingness to participate. With respect to data collection it were used multiple techniques: documentary, interviews and observation. The results showed that the ERP system does not include the variability of the production system and that the agents regulate the activity through the use of other tools.
Avaliação pancreática de animais submetidos à dieta hiperlipídica
(Universidade Federal de São Carlos, 2012-09-04)
Pisani, Graziéle Fernanda Deriggi
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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/4835384433555310
The pathogenesis of type 2 diabetes mellitus (DM2) is associated with insulin resistance (IR) and pancreatic β cells (β cells) defect. Adipose tissue modulates metabolism by releasing free fatty acids (FFA), glycerol, pro-inflammatory cytokines, chemokines and hormones. The increased production of most of these factors compromises insulin action in target organs, leading to IR. The lack of β cell adaptation to IR leads to hyperglycemia and DM2. The mechanisms of β cell adaptation are not well established. The objective of the present study was to evaluate the morforlogical and functional patterns of the progression of IR and DM2 development in an animal model of obesity and DM2. Swiss mice were divided into two groups: control (C), received standard diet; HFD group, received high-fat diet. Glucose (GTT) and insulin (ITT) tolerance tests were performed tests at 3, 7, 11 and 15 weeks of diet regimen. Animals of both groups were sacrificed by decaptation at 4, 8 and 16 weeks of diet regimen and pancreatic tissue was analysed. Fasting glycemia and GTT and ITT responses were significantly different in HFD from C group. Immunohistochemical analysis showed that islets area increased and insulin expression decreased in islets of HFD group compared with C group. The expression of the anti-apoptotic factor, Bcl-2, and the concentration of the citokines, TNF-α (factor tumor necrosis factor-α) and IL-1β (interleukin-1β) determinated in pancreatic homogenate by ELISA were not different in the groups. The results indicate that high-fat diet regimen induces pancreatic morphological and functional derangements associated with the development of DM2 in swiss mice. The study also suggests that TNF-α, IL-1β and Bcl-2 are not involved in the pathogenesis of DM2 in this model.
Estudo de primeiros princípios das propriedades eletrônicas de novos materiais derivados do grafeno : as nanofitas e nanofios
(Universidade Federal de São Carlos, 2012-09-05)
Oeiras, Rodrigo Yoshikawa
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Moreira, Fernando Manuel Araújo
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https://lattes.cnpq.br/1809254923092721
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https://lattes.cnpq.br/7950372795840464
In this thesis, we study new materials derived from graphene, like nanowires and nanoribbons, with numerical calculations based on the density functional theory (DFT) and the non-equilibrium Green functions (NEGF). We will discuss these theories in general and we remark that these theories are based on quantum mechanical. The results of this study indicate that the carbon ribbons and carbon wires present interesting and not predictable structural properties. The analysis of the density of stated (DOS) and its variants (LDOs, PDOS, and COOP), provides the basis for understanding the structural properties and the electronic structure of the wires and ribbons. Whenever possible, we compare the results obtained with DFT and NEGF with simpler theories, such as the valence orbital theory and the molecular orbital theory. The results show that the transport current is robust and presents an anisotropy in transmission of electrons, indicating these materials are candidates for fabrication of electronic devices, such as transistors.
“Xupa, CAASO!” : masculinidades e relações de gênero na Associação Atlética Acadêmica da UFSCar
(Universidade Federal de São Carlos, 2012-09-06)
Floeter, Guilherme Saade
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Escudeiro, Richard Miskolci
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https://lattes.cnpq.br/1623888309974862
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https://lattes.cnpq.br/4629950323228339
This study, done from a ethnographic research (participant observation and interviews) undertaken among undergraduate students of the Federal University of São Carlos (UFSCar), specifically those who participates in the Academic Athletic Association (AAA), presents as main object to analyze how these students show in their practices and discourses within the university environment, the construction of the masculinity(ies) based on gender relations. From the rivalry between UFSCar and USP campus in São Carlos, we try to show how there is a process of gendering and sexualization of both institutions, culminating in the construction of two regulatory poles of gender intelligibility: in one hand, USP, seen as masculine space, because the vast majority of their courses, Engineering, is allocated in the area of Exact Sciences, supposedly more rational and men (heterosexual); and in the other, the UFSCar, university composed of Humanities courses Biological and, in addition to Exact Sciences, and therefore supposed place of women, sensitivity and lack of rationality. Such rivalry, as will be exposed in the text, is not between the two institutions, but among men who are part of them, which shows a continuous process of construction of masculinities, crossed by misogynistic and homophobic speeches, where the constant effort is to reject, deny and ridicule everything that approaches the female pole and homosexuality.
Relatos, trajetórias e imagens: uma etnografia em construção sobre os Ye'pâ-masa do baixo Uaupés (alto rio Negro)
(Universidade Federal de São Carlos, 2012-09-06)
Rodrigues, Raphael
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Andrello, Geraldo Luciano
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https://lattes.cnpq.br/5447074379881029
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https://lattes.cnpq.br/5658153163114667
This study aimed to observe the motivations of an indigenous leader of the Northwest Amazon, Maximilian Menezes, in his desire to produce a written record of the Inapéporã s trajectory and placement of hierarchical, one of about forty clans tukano. From the collection of mythical and historical narratives attempted to recover the trajectory of this group from the river Papuri toward the lower river Uaupes contributing thereby to a greater understanding of the ethno-sociological conformation of this region. The history of the community of Ananás, where Max was born, and where co-lived with another tukano clan, the Sanadepó-porã, was rebuilt, in part, from these oral histories and historical sources, mainly. We tried to observe, from conflicting reports of episodes involving specific movements related to shamanism and scatter some of the groups own dynamic tukano regarding mainly the formation of communities, micro-politics of affinity and co-residence between agnatic groups. This paper revisits classic themes of regional literature as hierarchy, social organization, cosmology, and is constituted as a starting point for research collaboration marked mainly by the fluidity between native and anthropological knowledge.
Estudo da dinâmica populacional e interações biológicas de Dendrocephalus brasiliensis (Pesta, 1921) em ambientes experimentais
(Universidade Federal de São Carlos, 2012-09-06)
Paccagnella, Yeda Carolina
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Melão, Maria da Graça Gama
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https://lattes.cnpq.br/8342306603661310
The planet Earth is facing a serious crisis of the biodiversity loss. Often, human activities are responsible for biological invasions that alter significantly the various ecosystems and could lead to the extinction of native species. Dendrocephalus brasiliensis ( branconeta ) is a native freshwater Anostraca species, which has been studied and used in aquaculture to replace the brine shrimp originating from saline environments. Its occurrence in natural environments was recorded in Brazilian southeast and northeast regions, from the city of Urucuia-MG to Piauí State. However, there are records of its accidental introduction into fish ponds in São Paulo state, cities of Tabatinga and Arealva. The goal of this work is the study of the interactions of competition and predation / herbivory between D. brasiliensis and other planktonic species native of São Paulo in order to assess the possible impacts of a possible introduction of this species in natural environments where it does not occur originally. This study was conducted in an experimental system (10.000L tank) in Aquaculture Station of Department of Hydrobiology (EA-DHb), Federal University of São Carlos (UFSCar), São Carlos, SP, Brazil. Initially, the experimental tank was inoculated with the green algae Pseudokirchneriella subcapitata grown in laboratory. After the establishment of phytoplankton, zooplankton species were collected in limnic ecosystems of São Paulo state, in particular near São Carlos (June and July/2011), for the establishment of a zooplankton community in the experimental tank. Zooplankton succession in the tank was monitored for 133days before the introduction of branconeta. To evaluate the interaction of D. brasiliensis with other zooplankton species, the experimental tank was divided in two equal compartments that do not communicate to each other: one of them was kept with the original composition of the zooplankton, while in the other, cysts of the anostracean were introduced. In both experimental compartments samples were collected daily during 39 days, for quantitative and qualitative analyzes of zooplankton community, besides chlorophyll a, physical and chemical variables. The environmental variables were correlated to zooplankton groups using the statistical method of Canonical Correspondence Analysis (CCA). Numerical densities of Cladocera and Copepoda groups decreased in the presence of D. brasiliensis. We can conclude that the presence of D. brasiliensis does not exclude but significantly alters the composition and density of the plankton community.
A cor de queima dos suportes de porcelanatos esmaltados
(Universidade Federal de São Carlos, 2012-09-10)
Conserva, Lisandra Rafaela dos Santos
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Boschi, Anselmo Ortega
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https://lattes.cnpq.br/3259846931278607
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https://lattes.cnpq.br/7757508543729131
Brazil is a protagonist in the market of ceramic tiles. Porcelain stoneware is part of this supply chain with added value due to its excellent technical and aesthetic features, which higher acceptance in the market. Although the color of the holder is no longer visible after application of the porcelain stoneware enameled, it is critical to the consumer: the whiteness seems to be greater value and product quality. Reddish hues are directly related to the content of chromophores ions from raw materials, mainly present in clays and phyllites, which are the major components of the mass. Accordingly, it is essential to study conditions permitting the use of raw materials with a content of chromophores ions not so restricted. Thus, this study was divided into two stages. At first several typical porcelain stoneware masses were evaluated in differents firing temperatures. Data were organized in order to identify the main variables that affect the color of burning. In the second stage, procedures were conducted in order to evaluate the efficiency of maneuvers that can improve the tone of stoneware, enabling the use of masses with higher content in chromophores ions than usual, by simple methods and readily applicable to industry. The results obtained contributed to the identification of variables responsible for color formation and found that is possible the use of raw materials with levels of chromophore ions relatively high.
Efeitos periféricos e centrais decorrentes da exposição à cocaína e testosterona em ratos adolescentes e adultos
(Universidade Federal de São Carlos, 2012-09-11)
Engi, Sheila Antonagi
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Planeta, Cleopatra da Silva
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https://lattes.cnpq.br/8519239093983320
Drug abuse is considered a major public health problem in the world. The use of cocaine and anabolic-androgenic steroids (AAS) has increased in Brazil. Epidemiological studies indicate that adolescents are more vulnerable than adults to progress from the occasional use of drugs to dependence and that teenagers have a higher incidence of cocaine and testosterone abuse. There is evidence that testosterone can modify the acute effects of cocaine and increase dopaminergic transmission that could lead to behavioral cross-sensitization. Studies have shown that the use of cocaine or ASS promotes toxicity to the heart and liver. Thus, the purpose of the present study was to investigate: 1) whether the prior administration of AAS could cause cross-sensitization with cocaine and thereby increase the vulnerability to abuse and dependence to this psychostimulant, 2) the cardiovascular effects resulted from chronic use of these substances combined and 3) the toxic effects resulted from chronic use of these substances combined. In this way, our results showed that chronic administration of testosterone caused cross-sensitization to cocaine in adolescent, but not in adult rats. And that the combined chronic administration of testosterone and cocaine caused increased MAP, SAP and DAP in adult, but not in adolescent rats. Furthermore, our results showed that the chronic testosterone and cocaine administration caused no damages to liver cellules but caused severe damages to heart tissue in adolescent and adult rats.
Módulo elástico como ferramenta para o acompanhamento de transformações in situ e desenvolvimento de concretos refratários
(Universidade Federal de São Carlos, 2012-09-12)
Souza, Tiago Marcolino de
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Pandolfelli, Victor Carlos
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https://lattes.cnpq.br/7369376873984839
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https://lattes.cnpq.br/6302194006113059
Refractory castables are multiphase materials usually exhibiting complex heterogeneous microstructures, which have their mechanical strength affected by chemical and structural changes. These microstructural changes directly affect the Young s modulus, as this property is strongly dependent on the chemical bonds, crystalline structure and flaws, such as porosity and cracks. For the Al2O3-MgO system, two transformations can be highlighted: the volumetric expansion associated with the magnesia hydration and the in situ spinel formation, both can play a role by increasing or decreasing the castable s embrittlement depending on the resulting expansion. Considering this aspect, the addition of MgO sources with different reactivity in refractory castables was evaluated during curing and drying steps. As a result, different routes for magnesia s sources addition to the castables, without the usual damage caused by MgO hydration, are presented in this work. The addition of acetic acid sped up the brucite precipitation, inducing the formation of a resilient structure able to inhibit the stresses generation. Additionally, the effect of mineralizing or densification compounds on spinel-forming castables and the microstructural evolution of refractory castables containing different MgO sources, colloidal binders or high-carbon content were assessed during the thermal treatment by hot Young s modulus measurements using the resonance bar technique. The attained results highlight the technique s broad feature and accuracy for the development of refractory materials. The MgF2 and magnesium borate addition sped up the spinel formation, whereas TiO2 led to lower expansion values and greater rigidity at high temperatures, all of them as promising alternatives to master the castable s microstructure design. For the nano-bonded castables, the sintering additive addition further enhanced the Young s modulus resulting in high-performance refractories. Additionally, the elastic modulus measurements were able to evaluate the antioxidants effect in high-carbon containing castables and to identify the mechanisms of crack healing (during heating) and opening (during cooling).
Monitoramento de Ambientes Virtuais Distribuídos com suporte a clientes sob projeção única e multiprojeção
(Universidade Federal de São Carlos, 2012-09-12)
Penteado, Maurício Giacomini
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Trevelin, Luis Carlos
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https://lattes.cnpq.br/5082419783043736
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https://lattes.cnpq.br/3558493336659272
Immersive, interactive, and collaborative distributed applications, due to their real time and multi-platform characteristics, require a monitoring structure of their functionalities during the development period, which is not fully available in the current monitoring systems, which are usually specific of the languages and platforms in which they are made available. Monitoring systems that require synchronism of distributed objects during the processing is a complex task. Especially in distributed systems from multi-projection where timing is critical to its operation. It is often difficult to check the correct execution of the system. It might be useful for developers and users of such systems to have the ability of identifying, for example, if the reason for the system delay is due to the abusive use of a resource or due to programming mistakes; the identification of which object has crashed, compromising the system as a whole. Distributed object systems, also known as SOA (Service Oriented Architecture), generally use middleware of the broker type in their infrastructure and can have a dynamic number of connected clients or servers when running. There are, in the literature, several tools for the monitoring of performance, resources, debugging, and support, among others, of such systems. Nevertheless, the tools available in the literature are limited to programming languages or platforms that are able to process the monitoring agents related to them. In this work, a tool for the monitoring of distributed object systems is proposed, based on communication described in XML documents, which allows language and platform independence in the such systems development. A structure for the design of tools for the monitoring of distributed object systems is proposed, based on communication described in XML documents, which allows language and platform independence in the such systems development. In addition to the structure that is theoretically founded, the conception of a tool is structured in the manner described and proven in monitoring data from a case study.
Condutividade iônica e atividade termodinâmica em vidros x AgI (1-x) AgPO3, 0 ≤ x ≤ 0,5
(Universidade Federal de São Carlos, 2012-09-14)
Bragatto, Caio Barca
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Rodrigues, Ana Candida Martins
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https://lattes.cnpq.br/4499231813051400
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https://lattes.cnpq.br/5833076761496241
The ionic conductivity in solids is known since the 19th century, but the mechanisms of charge carriers transportation in amorphus solids is not yet fully known. The control of ths property is especially important for the development of fast ionic conductors (FICs) that can be applied in cell storage in electrochemical cells or in selective membranes. Through the dissolution of halogenate salts in a vitreous matrix, we can observe an increase of up to five orders of magnitude in the ionic conductivity of some glasses. To investigate this great variation of ionic conductivity, we propose a model based in the “weak electrolyte theory”. This theory, that says that the glass is a solution where the modifier (solute) is weakly dissociated in the vitreous matrix (solvent), was proposed in the 70’s to explain the non-linear increase of ionic conductivity in glasses with the increase of network modifiers (alkaline oxides). Were sintetized glasses from the family x AgI (1-x) AgPO3. The characterization showed interesting results, specially in the x ray diffraction, with the detection of a second amorfous halo for compositions with higher AgI content. Also, were realized impedance spectroscopy measurements, with a wide range of temperature, to determine the conductivity of the samples. To verify the proposed model, we proposed an experiment based in electrochemical cells, in wich we relate the electromotive force with chemical activity of AgI in the glass. We tested two methods to measure the activity of AgI: the first uses two batteries – one wich is a reference, using pure AgI, and the second with the glasses x AgI (1-x) AgPO3 . The second method is a concentration cell.
Desenvolvimento de borracha termoplástica por vulcanização dinâmica. TPV-(NBR+PP)
(Universidade Federal de São Carlos, 2012-09-14)
Herrera, Julio César Alzate
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Pessan, Luiz Antonio
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https://lattes.cnpq.br/8276650236213537
The union of technology of thermoplastic and rubber has contributed to the development of thermoplastic elastomers (TPE), which was evidenced through the study of patents in TPE in the last 20 years, where Japan and the United States are the leaders. Trends in TPE are: modification to polymer structure in styrenic TPEs in order to employ the dynamic vulcanization, use of nanofibres and nanoclays, and resists oil TPEs using hydrogenated nitrile rubber to improve the properties of hot air and aging. The main variables in the development of TPE should take into account the surface energy the thermoplastic and elastomer, the elastomer entanglement, crystallinity of thermoplastic, proportions of the thermoplastic and compatibilizer. Typically the articles produced with nitrile, may be obtained using the technology or conventional rubbers (vulcanized), and not having possibility of recycling of defective products and materials vulcanizates. The purpose is to develop a thermoplastic nitrile rubber by dynamic vulcanization (TPV-(NBR + PP)) using conventional techniques for mixing between nitrile rubber and polypropylene. The development of nitrile rubber thermoplastic by dynamic vulcanization, TPV (NBR+PP) were studied with variation of vulcanization system, variation of proportion of NBR/PP and type of compatibilizer. The main results on development of TPV-(NBR+PP) were obtained with the use of system of vulcanization type phenolic resin, with compatibilizer Ph-PP and with 4,0phr of amine (6PPD). Developed a nitrile rubber thermoplastic by dynamic vulcanization (TPV-(NBR + PP)) with good performance in reprocessabilidade, using equipment and techniques conventional thermoplastic processing, which will help to satisfy the demands of industry.
Esboço de uma rede de cooperação em um arranjo produtivo local na indústria calçadista paulista
(Universidade Federal de São Carlos, 2012-09-14)
Queiroz, Timóteo Ramos
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Côrtes, Mauro Rocha
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https://lattes.cnpq.br/6281411676195221
Clusters of companies have been widely studied by gains from the actors that compose them. However, the strong bias for such studies still fall on the economic benefits and very little to address the attributes of social relationships that constitute, integrate and maintain such networks. So, we decided to studies and surveys of clusters, choosing to focus on Local Productive Arrangements (APLs), among the many possible configurations. In order to advance this work in this area has focused on design, characterize and analyze the networks of cooperation between industrial companies in a Local Productive Arrangement (APL) are the footwear of Sao Paulo. It then took the footwear cluster at Jaú, State of São Paulo. The method used for data collection was a questionnaire on the spot for the key players that made up the network and then sending structured questionnaires to companies. The data generated were converted into ordinal qualitative variables, so that it is possible to use the software UCINET version 6.283, to design and measurement network. The analysis provided an understanding and measurement of the relationship networks of enterprises and the network present in APL. It turned out that the social motives for cooperative action by the companies were classified as the same weight as economic reasons.
Efeitos da alimentação/digestão e do jejum prolongado sobre a função cardíaca de cascavéis, Crotalus durissus terrificus
(Universidade Federal de São Carlos, 2012-09-14)
Paula, Gabrielle Silveira de
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Kalinin, Ana Lúcia
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https://lattes.cnpq.br/5493936744279888
Some snakes have the ability to survive long periods without food and are capable to ingest large meal size. The ingestion of proportionally large preys triggers an expressive increase on the oxidative metabolic demand (SDA Specific Dinamic Action) which can become several times higher than the resting metabolic rate. The two described extreme situations might lead to cardiac changes to adapt structure and function in order to afford these two opposite physiological demands. During long food deprivation (Phase III), the depletion of the body structure may affect the heart muscle. That should be reverted to the SDA and prevent an overload on cardiovascular system. The standard cardiac function of South-american Rattlesnake, Crotalus durissus terrificus, was described as well as the changes caused by long term food deprivation and SDA. The importance of sodium-calcium exchanger (NCX), functionality of sarcoplasmic reticulum, extracellular calcium dependence and the effect of adrenergic stimulation were tested in adult animals at 30°C, under three different metabolic states: postabsorptive, SDA peak and food deprivation. The ventricular mass does not change after food deprivation and SDA. The force of contraction was higher in the base of the heart if compared to the apex, but there is no difference among the experimental groups and it is probably reflex of the fiber orientation in each region of the ventricle. The sarcoplasmatic reticulum is functional in all groups, but the dependence of reticular calcium is lower during starvation compared to the other groups. Muscle contraction is mostly supported by the extracellular Ca2+. The NCX have minor contribution to force generation (20%) but has a major role pumping calcium out of the cell (faster than SERCA). The increase in extracellular Ca2+ concentration during digestion can augment twitch force and would represent a contractile advantage to support the increased cardiac work without the development of hypertrophy. The adrenergic stimulation produced sustained increase in Fc for a wide range of stimulation frequencies in all the tested groups.
Síntese da zeólita Beta usando planejamento experimental e emprego na isomerização do n-hexano
(Universidade Federal de São Carlos, 2012-09-14)
Oliveira, Kátia Dionísio de
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Cardoso, Dilson
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https://lattes.cnpq.br/2462847535959232
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https://lattes.cnpq.br/6620016276509499
This work aimed to apply the Design Of Experiment (DOE) methodology as an auxiliary tool to evaluate the conditions of synthesis of the aluminum-rich zeolite Beta. Bimetallic catalysts with 50% platinum and 50% nickel (50Pt50Ni) supported on zeolites with various Si/Al ratios were synthesized, characterized and evaluated in the isomerization of n-hexane. In the first part of this work, five variables related to the synthesis of zeolite Beta were evaluated by a series of statistical designs, in which the response variables were the relative intensities of the X-ray patterns and the yield of phase BEA. The results of the t-test showed that the ratio TEAOH/SiO2 is not significant for the formation and crystallization of zeolite Beta. However, the interaction of this variable with the Si/Al ratio was statistically significant. In order to obtain the aluminum-rich zeolite Beta, the samples were synthesized with partial substitution of cations TEA+ by cations Na+. The XRD patterns of these samples showed that BEA phase was formed using a Si/Al ratio of 5,0 and 7.5. These low values of Si/Al ratio were confirmed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and energy-dispersive X-ray spectroscopy (EDS). Information about the main properties of the 50Pt50Ni catalysts such as activity, conversion and selectivity to di-branched isomers in the isomerization of n-hexane were obtained by performing catalytic tests. Concerning these properties, the catalysts supported on the synthesized zeolite Beta (Si/Al = 7.5) showed better catalytic performance compared with catalysts supported on commercial zeolite Beta (Si/Al = 9.0). Additionally to these tests, a study on the kinetics of reduction of ions Pt2+ and Ni2+ on these catalysts was conducted using X-ray absorption spectroscopy (XAS). The combination of XAS analysis and catalytic tests showed the importance of maintaining a bimetallic platinum and nickel system in order to obtain satisfactory performance of catalysts applied to the isomerization of n-hexane. The XAS results suggested that Pt2+ ions are reduced in lower temperatures compared to Ni2+ ions, and that the addition of platinum to the nickel-based samples promoted the reduction of Ni2+ ions. The catalytic results suggested that equilibrium between acid and metal sites exists during the isomerization of n-hexane. The understanding of this equilibrium is of major importance to increase the yield and selectivity to di-branched isomers.