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Distribuições discretas para duas observações inflacionadas
(Universidade Federal de São Carlos, 2021-07-30) Hebling, Luisa; Conceição, Katiane Silva; https://lattes.cnpq.br/5789619620619667; https://lattes.cnpq.br/2173304528541755
Count data is often found in many real applications and some observations may occur in the data set in an excessive amount. In many real problems it is quite common for the data set to contain excesses of zero and one observations. In a more general context, k1 and k2 are defined as observations of a particular data set that have discrepancy (excess) in their frequencies, making modeling from traditional discrete distributions inappropriate. Thus, the main objective of this work is to propose the k1 and k2 Inflated Power Series family of distributions, aiming to model data sets that present such discrepancy in the observations k1 and k2. In order to estimate the parameters we consider classical approach, with the maximum likelihood method, using a hurdle version of distributions. Some applications considering real data sets will be presented.
Influência da sombra do dossel temporário de um sistema agroflorestal na maturação de frutos de café
(Universidade Federal de São Carlos, 2021-07-30) Leite, Paulo Henrique Marquezini; Oliveira, Renata Evangelista de; Bigaton, Ademir Durrer; https://lattes.cnpq.br/6777223792862756; https://lattes.cnpq.br/1201801613118649; Fontanetti, Anastácia; https://lattes.cnpq.br/3598362104615834; https://lattes.cnpq.br/5874455924064706
In Brazil, coffee trees have been included in agroforestry systems, mainly due to climatic emergencies and increased demand for specialty coffees. The shading levels inside a multi-layered agroforest depend on the design, management and, mainly, on the development time and evolution of the system. Understanding these variations over time, as well as the effects of temporary canopy on coffee production components, can contribute to the definition of more efficient agroforestry designs, especially in agroforestry systems (SAFs) in the establishment phase. In a four-year-old young agroforestry coffee plantation, in the process of stratification and establishment with a temporary canopy formed by Ricinus communis L., we aimed to evaluate the shading levels and its influence on the maturation of coffee (Coffea arabica L.) Bourbon amarelo . The shading was determined at four distances, at 1 m (D1), 4 m (D2), 7 m (D3) and 10 m (D4), from the sunniest edge (North face) to the interior of the SAF. We evaluated the shading levels, calculated by the difference of photosynthetically active radiation (PAR) in full sun and inside the SAF, quantifying the total volume of produced fruits, the percentage of dry fruits and the dry biomass of the coffee tree. As the distances from the edge to the interior of the SAF increased, the greater was the shading level. The evaluated coffee trees responded homogeneously within each distance, the more shaded ones produced a greater volume of fruits and a smaller percentage of them, dry. Coffee dry biomass was higher at distance D4. This work contributes to the understanding of how environmental factors, design and management of agroforestry influence the maturation of coffee fruits, a crucial factor for ordering the harvest and production of better quality coffees.
Efeito do material particulado atmosférico (MPA) sedimentável proveniente da atividade siderúrgica sobre a função cardíaca de tilápia, Oreochromis niloticus
(Universidade Federal de São Carlos, 2021-07-30) Adorno, Henrique Aio; Monteiro, Diana Amaral; https://lattes.cnpq.br/0358411551730768; https://lattes.cnpq.br/7384615643107023
The industrial activity for obtaining and processing metal alloys, iron and steel result in the emission of Sedimentable Atmospheric Particulate Material (SAPM). Mining-steel industries located in the “Complexo do Tubarão”, in Metropolitan Region of Vitoria (MRV), Vitoria – ES, emit a metal smoke commonly called "black powder" that contains a varied composition of metals and metal nanoparticles that are deposited in aquatic environments. Faced with a scenario that seeks to produce information that can help the sustainable management of water resources, the objective of this study was to evaluate the possible effects of acute exposure (96 hours) of sublethal concentrations of 0.01 g.L-1, 0.1 g.L-1, and 1.0 g.L-1 of SAPM on myocardial contractility of Nile tilapia, Oreochromis niloticus. The group exposed to 1.0 g.L-1 of SAPM showed significantly higher values of contraction force (Fc) and cardiac pumping capacity (CPC) at all stimulation frequencies. In the exposed animals, time-dependent parameters (TPT = time to peak tension, and THR = time to 50% of relaxation) were lower, while contraction and relaxation rates were higher. All groups exhibited a Fc decay after the non-physiological diastolic pause of 300 seconds, which was more conspicuous in the exposed groups, suggesting a prominent role of the Na +/Ca2+ (NCX) exchanger in calcium extrusion. As the 1.0 g.L-1 concentration of SAPM showed pronounced effects on cardiac contraction, we also investigated the effects of this exposure on hematological parameters and plasma biomarkers of stress response and oxidative stress. Alterations in myocardial contractility in MPAS-exposed fish were associated with a stress response characterized by significant increases in plasma cortisol and glucose levels. Tilapia exposed to SAPM also showed a significant reduction in hemoglobin content indicating a possible hypoxemia state, which may require adjustments in cardiac output, with increased Fc to increase systolic volume. The exposed fish showed higher values of hepatosomatic index and relative ventricular mass, probably associated with the overload of activity of the heart and liver. Additionally, SAPM exposure induced significant increases in plasma levels of lipid peroxidation and protein carbonylation, indicating oxidative stress and reflecting an imbalance of redox homeostasis. NCX protein expression showed no significant difference between the groups, indicating that the positive inotropic and lusitropic effects are associated with β-adrenergic responses during stress situations. Thus, the effects of SAPM may negatively affect the adaptation, survival and reproductive success of tilapia, as the energy requirement to maintain the physiological patterns of the cardiovascular system and the detoxification processes demanded by SAPM exposure is high.
Análise de falha de martelos oscilantes de desfibradores utilizados em usinas sucroalcooleiras
(Universidade Federal de São Carlos, 2021-07-30) Sasso, Ricardo Aparecido; Koga, Guilherme Yuuki; https://lattes.cnpq.br/0933095081175012; Gargarella, Piter; https://lattes.cnpq.br/4641435644243916; https://lattes.cnpq.br/0729608886539669
Sugarcane mills have demanded more control of their production line, reduced loss of raw material, and a longer period before maintenance of their equipment, aiming to increase their profitability. The main station of this process is the mill responsible for crushing the sugar cane. Its components such as knives, hammers, and rollers are subject to degradation processes, mainly wear and corrosion, decreasing production efficiency and increasing the maintenance costs. This work aims to perform the failure analysis of hammers coated with weld, removed from a mill shredder after use. Through compositional characterization techniques, it was determined that the base material is a 1030 carbon steel, and the coating is a high Cr (22,2 %wt) and C (3,65 %wt) ferrous alloy. The coating showed greater resistance to abrasive wear compared to the base and reference material (410 stainless steel), it has greater hardness and hard carbides (type M7C3) that act as reinforcement and protection elements against the removal of the soft matrix material of ferrite and austenite by abrasive action. Despite the complexity of sugarcane juice, composed of chlorides, sulfides, and organic acids, the cyclic polarization curves did not show significant differences between the materials tested in this corrosive environment. The 410 stainless steel had better performance against corrosive effects, due to the complete dissolution of Cr in the solid solution, which ensured the formation of a protective passive film, which, unlike the coating, with a high content of Cr, creates carbides in excesses and interfaces depleted in Cr, representing preferential points for corrosion. The cracks in the coating allowed the penetration of the sugarcane juice, and subsequent detachment of the weld by impact, exposing the base material to abrasive wear and corrosive. Greater control during the coating preparation process and the use of a base material with greater corrosion resistance could significantly extend the life of the hammers.
Interações entre estrutura da vegetação e fertilidade do solo na decomposição da matéria orgânica em diferentes usos do solo
(Universidade Federal de São Carlos, 2021-07-30) Bessi, Débora; Tanaka, Marcel Okamoto; https://lattes.cnpq.br/2768658925977757; https://lattes.cnpq.br/0893444898265301
Forests play a fundamental role in providing ecosystem functions and services. In particular, the relationship between forest and soil is an important link for ecosystem functioning and maintenance of services such as nutrient cycling. Despite this, a high loss of natural forest area has been observed, mainly due to the conversion into agricultural area, strongly impacting the biogeochemical cycles. Agroforestry systems and ecological restoration practices are capable of playing a fundamental role in the resumption of ecosystem functions. It is expected that the introduction and growth of the plant community favors nutrient cycling and carbon fixation, which are strongly influenced by organic matter decomposition rates. The litter decomposition process is complex, involving interactions between physical, chemical and biological soil characteristics, litter chemical characteristics, local vegetation structure and climatic variation. Thus, this study aimed to evaluate the effects of plant structure and soil quality, in areas with different land uses, on the decomposition processes of organic matter as estimated by decomposition rates k and stabilization factor S. We used the TBI (Tea Bag Index) method to assess k and S and evaluate decomposition in agroforestry systems, successional stands at different ages of forest restoration and mature riparian forests. The direct and indirect effects of the sampled variables were estimated using structural equation models. Our results showed that intensive pasture systems and pastures intercropped with crops present a more dynamic nutrient cycling (higher k), whereas in areas with silviculture inclusion there was a greater contribution of recalcitrant organic matter and material stabilization (higher S). When comparing riparian forest areas, restored areas and pastures, the results indicated that the stabilization of organic material is greater in forest areas compared to pasture areas, with a tendency to increase with the advancement of succession and soil fertility. In contrast, decomposition rates were higher in open areas under pasture, but also showed a positive variation with nutrient content. These results suggest that the diversification of integration systems favors nutrient cycling and carbon sequestration due to the lower nutrient loss through decomposition and stabilization of the organic matter, contributing to the sustainable management of pastures. In addition, plant restoration practices can be a good strategy to increase the input of organic material into the soil considering the increase in organic matter stabilization when compared to pastures, contributing to the improvement of its quality and, mainly, increasing carbon sequestration via stabilized material.
Para que servem as eleições municipais? Estratégias políticas na competição local
(Universidade Federal de São Carlos, 2021-07-30) Martins, Thais Cavalcante; Kerbauy, Maria Teresa Miceli; https://lattes.cnpq.br/4762029784021248; https://lattes.cnpq.br/5764763788709997
The objective of this research is to investigate the strategies of political actors in local electoral competition, focusing on two dimensions. The first concerns legitimate and formal means, with an emphasis on the provisions established by the electoral system that increase one's chances of accessing power. It also explores the levels of competition as well as the conditions of competition. The second dimension delves into the instruments that enable candidates and parties to monitor elections and the occurrence of electoral irregularities. Such devices are assessed as a political strategy available to candidates and parties both before and after voting. The general hypothesis is that variation in strategy use is related to factors exogenous to elections, but it is also due to institutional factors, such as the level of competitiveness in municipal disputes. Based on an analysis of electoral, socioeconomic, and jurisprudence data, descriptive statistics and logistic regression techniques were used to investigate the variation and test the hypothesis. The study focuses on the dispute for the municipal executive position between 2000 and 2016, covering all Brazilian municipalities. The findings support the hypothesis and demonstrate that, even though elections have become more competitive and monitored, they continue to coexist with abusive practices, which are not necessarily limited to the country's less developed territories.
Influência de modificações superficiais na resistência à corrosão e na bioatividade da liga beta ti-40nb para aplicações biomédicas
(Universidade Federal de São Carlos, 2021-07-30) Ricci, Virgilio Pereira; Jorge Júnior, Alberto Moreira; https://lattes.cnpq.br/6360362248108490; Afonso, Conrado Ramos Moreira; https://lattes.cnpq.br/2176215981291453; https://lattes.cnpq.br/3969440533061195
β-titanium (Ti) alloys have great applicability in the biomedical area due to properties such as low density, high corrosion resistance, low elasticity modulus (E), and biocompatibility. However, these alloys are not bioactive. It is necessary to make surface modifications producing bioactive surfaces and with better electrochemical properties. For these reasons, this work evaluated the bioactivity performance and corrosion resistance of the Ti-40Nb alloy modified superficially by anodization, producing the amorphous nanostructures of nanotubes (NTs-AM) and nanopores (NPs-AM). Initially, the annealing was carried out on anodized samples with amorphous nanostructure to reduce the alloy’s E and crystallize the amorphous nanostructures in a mixture of anatase and rutile, obtaining these characteristics with annealing at 550 °C, namely NTs-HT and NPs-HT. The precalcification (PC) process was performed to increase the bioactive behavior of NTs-HT and NPs-HT, that is, NTs-PC and NPs-PC. The electrochemical behavior was studied by open circuit potential (OCP), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). Samples with NTs-HT and NPs- HT showed the highest corrosion potential (Ecorr) and lower passivation current density (ipass), with the lowest ipass of ~0,3 μA/cm² being observed in NPs-HT. The EIS simulation by equivalent electrical circuits (EEC), the NPs-HT showed greater resistance and thickness of the barrier layer. After 14 days of soaking in SBF, it was not observed HAp formation in the unmodified substrate, NTs/NPs- HT conditions exhibited moderate apaite formation. In contrast, NTs/NPs-PC samples showed high apatite formation, with apatite mass gain ~3.5x higher than anodized and annealed samples.
Alterações hemodinâmicas, cardíacas e vasculares induzidas pelo treinamento físico combinado em ratos espontaneamente hipertensos tratados ou não com Dexametasona
(Universidade Federal de São Carlos, 2021-07-30) Tardelli, Lidieli Pazin; Cardoso, Sandra Lia do Amaral; https://lattes.cnpq.br/2030708742766455; https://lattes.cnpq.br/2105752094418176
Arterial hypertension (HT) is usually accompanied by neural, cardiac and vascular alterations. Dexamethasone (DEX)-induced hypertension is observed in normotensive rats, but little is known about the effects of DEX of arterial stiffness and vessel remodeling on normotensive and spontaneously hypertensive rats (SHR). Combined training (aerobic exercise on alternate days with resistance exercise) has been recommended as a preventive and non-pharmacological treatment for HT, but the mechanisms induced by combined training to reduce HT are not totally known. Therefore, the aim of this study was to evaluate the effects of DEX treatment on arterial pressure (AP) and arterial stiffening of Wistar and SHR, as well as the effects of combined training on the hemodynamics of SHR treated or not with DEX. Wistar and SHR were treated with DEX (50µg/kg s.c.) for 14 days. SHR were submitted to combined training for 74 days and were treated with DEX during the last 14 days. Echocardiographic parameters, AP, pulse wave velocity (PWV), as well as histological and morphometric analyses of the heart and aorta, carotid and femoral arteries were performed. The results show that control SHR (SHRCT) had higher AP then control Wistar (WCT), associated with autonomic imbalance to the heart. Echocardiographic changes in SHRCT (vs WCT) were suggestive of cardiac remodeling: higher relative wall thickness (RWT, +28%) and left ventricle mass index (LVMI, +26%) and lower LV systolic diameter (LVSD, -19%) and LV diastolic diameter (LVDD, -10%), with slightly systolic dysfunction and preserved systolic function. In addition, SHRCT had lower myocardial capillary density and similar collagen deposition area. PWV was higher in SHRCT due to higher aortic collagen deposition. DEX-treated Wistar rats presented higher AP (~23%) and autonomic imbalance to the heart. DEX did not change cardiac structure in Wistar, but PWV (+21%) and aortic collagen deposition area (+21%) were higher compared with control. However, DEX did not change AP, autonomic balance to the heart or arterial stiffness in SHR, but reduced RWT and LV collagen deposition area (-12% vs SHRCT). On the other hand, combined training reduced AP (~18%), PWV (-20%) in SHR (SHRTCT), which was associated with better autonomic balance to the heart, reduced myocardial collagen deposition (-18%), as well as lower collagen deposition aorta (-23%), carotid (-35%) and femoral (-14%). In addition, combined training completely blocked any increase of AP or estimated PWV induced by DEX in SHR, as it does in normotensive rats. No effect of DEX treatment or combined training on vessel remodeling was observed in arteries. In conclusion, the results suggest a differential effect of dexamethasone on arterial stiffness, myocardial remodeling, and AP between Wistar and SHR. On the other hand, combined training proved to be an important strategy to reduce AP and arterial stiffness in SHR, and these lower responses were maintained regardless of DEX treatment.
Discursos sobre a leitura em memes: a ‘vergonha’ e o ‘orgulho’ de ser leitor
(Universidade Federal de São Carlos, 2021-07-30) Silva, Jeniffer Aparecida Pereira da; Ferreira, Luzmara Curcino; https://lattes.cnpq.br/4849994635754652; https://lattes.cnpq.br/6680592122128813
In this dissertation, we report the results of the master's research we conducted in the Postgraduate Program in Linguistics at UFSCar with the Laboratory of Reading Studies (LIRE-CNPq), coordinated by Prof. Dr. Luzmara Curcino. In our research, we reflect on the discourses that circulate among us about reading, from the analysis of what is enunciated about it in the form of a current genre: the internet memes. Assuming from the assumption that much of what we know and reproduce about reading goes back, according to Chartier (1998) and Abreu (2001, 2006), to a history of long duration, in which is inscribed everything that we enunciate about this practice, we seek, in our analysis, to survey and analyse some of these discourses mobilized in memes that have reading as a theme. For this survey and analysis, we went through, albeit very briefly, aspects of the history of reading in Brazil, in order to understand the historical, cultural and social reasons that guide what is said about this practice and about us, Brazilians, as readers. The Memes, despite their contemporaneity, like any cultural production, are historically and culturally determined and therefore, disseminate discourses that are shared collectively, that circulate as consensus among us, thus acting as another vector for their propagation. In order to evaluate possible regularities and differences that the meme could disseminate as to the way of enunciating about reading, we used theoretical contributions dedicated to the analysis of discourses about reading, such as Britto (1999, 2008), Barzotto and Britto (1998), Abreu (2001, 2006) and Varella and Curcino (2014), as well as in the perspective of Discourse Analysis of Foucault (1990) concerning the ways of apprehension of the operation of the discourse order that regulates the enunciable and the effects of its circulation, thus affecting the processes of subjectivation of subjects and their practices and the construction of discursive consensus on reading. We also work with authors who discuss and clarify fundamental aspects of the functioning of the meme, relating to its characteristics as a genre (BAKHTIN, 2010), the multimodality and homology of image and verbal languages that in general constitute it (CURCINO, 2011); the detachability of the culture of the fragment (MAINGUENEAU, 2015), its belonging to the field of humour (POSSENTI, 2020); to its peculiar mode of actualization of the author function (FOUCAULT, 2011; CURCINO, 2016a; ROSIN; CURCINO, 2015); finally, to its properties related to circulation, viralization, its replication and dissemination by social networks (ZOPPI-FONTANA, 2018, 2016; KOMESU, 2005; GAMBARATO; KOMESU, 2018; KOMESU; GAMBARATO; TENANI, 2018) among others. The research corpus consisted of 115 memes, of which 51 were actually cited or properly analysed throughout this dissertation. We concluded that the memes, despite remaining faithful to many of the hegemonic discourses about reading, in some cases tend to subvert certain representations, through humorous language plays and also through new visions about reading proposed by their constructors. This, however, is far from being a rule. Most of the time, the memes analysed are aligned with the discourses that commonly guide what can be said about the practice of reading.
Slice como serviço em edge computing e dispositivos IoT com restrição de recursos
(Universidade Federal de São Carlos, 2021-07-30) Azevedo, Rodrigo Ferraz; Paula, Luciano Bernardes de; https://lattes.cnpq.br/8755104082298597; Verdi, Fábio Luciano; https://lattes.cnpq.br/9143186843657940; https://lattes.cnpq.br/4338335955556745
A new concept that describes a federated framework that provides computing (processing), networking, and storage as a virtual slice framework, Cloud Network Slicing (CNS) enables new approaches to IoT applications and structuring resources at the edge of the network. Some characteristics of IoT devices, such as intermittent connection, battery power, low processing power, and other resource constraints, require new strategies to meet this new application profile. This research adopts the architecture defined in the NECOS Project and implements the functions for creating CNS in resource-constrained edge devices. The implementation was evaluated in Single Board Computer (SBC) hardware using lightweight virtualization solutions (microservices) and the results achieved confirmed the hypothesis of slice support in these devices with restricted resources, but with limitations to support multiple slices. Therefore, this work presents a brief study on the limitations of the NECOS project in resource-constrained environments, mainly in the IoT context, proposes and implements the extension of some NECOS components to support resource-constrained equipment, then analyzes the performance of the proposed on real IoT hardware using SBC.