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Models for inflated data applied to credit risk analysis
(Universidade Federal de São Carlos, 2016-09-27)
Oliveira Júnior, Mauro Ribeiro de
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Louzada Neto, Francisco
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https://lattes.cnpq.br/0994050156415890
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https://lattes.cnpq.br/6557207621229352
In this thesis, we introduce a methodology based on zero-inflated survival data for the purposes of dealing with propensity to default (credit risk) in bank loan portfolios. Our approach enables us to accommodate three different types of borrowers: (i) individual with event at the starting time, i.e., default on a loan at the beginning; (ii) non-susceptible for the event of default, or (iii) susceptible for the event. The information from borrowers in a given portfolio is exploited through the joint modeling of their survival time, with a multinomial logistic link for the three classes. An advantage of our approach is to accommodate zero-inflated times, which is not possible in the standard cure rate model introduced by Berkson & Gage (1952). The new model proposed is called zero-inflated cure rate model. We also extend the promotion cure rate model studied in Yakovlev & Tsodikov (1996) and Chen et al. (1999), by incorporating excess of zeros in the modelling. Despite allowing to relate covariates to the fraction of cure, the current approach does not enable to relate covariates to the fraction of zeros. The new model proposed is called zero-inflated promotion cure rate model. The second part of this thesis aims at proposing a regression version of the inflated mixture model presented by Calabrese (2014) to deal with multimodality in loss given default data. The novel methodology is applied in four retail portfolios of a large Brazilian commercial bank.
Modelos série de potência com excesso de zeros observáveis e latentes
(Universidade Federal de São Carlos, 2016-09-28)
Zavaleta, Katherine Elizabeth Coaguila
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Suzuki, Adriano Kamimura
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https://lattes.cnpq.br/4579497412852854
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Cancho, Vicente Garibay
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https://lattes.cnpq.br/3503233632044163
The present work's main objective is to study the significance of zeros in an observable and latent data. In observable data set that occur excess of zeros, its common to have sobredispersion. In this sense, the models zero-inflated power series (ZISP) were proposed to accommodate these excesses. Specifically for the analysis of observed data, it was made a study of gradient statistic, proposed by Terrell (2002), to test the hypotheses in relation to inflation parameter ZISP models. This test is based on evaluation of the performance of gradient statistic compared with the classical likelihood ratio (Wilks, 1938), score (Rao, 1948) and Wald (Wald, 1943) statistics. In addition, recently, fragility has being modeled by discrete distributions using non-negative integers values that allows zero fragility, which means, individuals who do not present the event of interest (fraction of zero risk). For this type of latent data, we have proposed a new survival model induced by discrete frailty with ZISP distribution. This proposal brings a real description of individuals without risk, because individuals cured due to genetic factors (immune) are modeled by fraction of deterministic zero risk, while the cured by treatment are modeled by fraction of random zero risk. In this context, we also developed the gradient statistic to verify parameter significance of zero risk for data modeled by fraction of deterministic zero risk. To show our proposals, we present the results of simulation studies and applications using real data.
Parâmetros seminais e extração de RNA espermático de mico-leão-de-cara-dourada (Leontopithecus chrysomelas)
(Universidade Federal de São Carlos, 2016-09-29)
Bacher, Patrícia Hergert
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Valle, Rodrigo Del Rio do
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https://lattes.cnpq.br/2879780464444096
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Peripato, Andréa Cristina
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https://lattes.cnpq.br/0657713343451089
The Golden-headed lion tamarin (Leontopithecus chrysomelas) is an endemic primate from Atlantic Forest threatened with extinction. Amongst the conservational efforts addressed towards the species is the use of reproductive biotechnologies as a strategy of genetic resources preservation and assurance of captive and natural population´s viability. The success of the reproductive biotechnologies still depends on the detailed knowledge despite the reproductive aspects, the investigation of factors that may influence the reproductive success and the establishment of specific-species protocols. The cryopreservation of semen is the most widely used approach for wild species. However, one major challenge associated to the appliance of neotropical primate´s samples consists in the formation of seminal clots, which invalidates the use of great quantity of gamete in most reproductive procedures. The golden-headed lion tamarin has become a promising model among threatened neotropical primates and aiming to contribute with the development of reproductive technologies, this essay had the objective of initiate investigations concerning the molecular and seminal factor which may have an effect on the reproductive potential of sexually mature males of Leontopithecus chrysomelas. Therefore, the animals kept at the Fundação Parque Zoológico de São Paulo, São Paulo, Brazil, were divided into two groups, “Old” (mean age 11,6 years; n=6) and “Young” (mean age 4,8 years, n=6) to execute the semen collection and evaluation of the seminal parameters (concentration, motility, plasmatic and acrosome membrane integrity, mitochondrial cytochemical activity and morphology). The analysis of seminal parameters pointed out significant differences between the older and younger subjects despite the plasmatic membrane integrity (p=0,049), acrosome integrity (p=0,009) and for Class IV mitochondrial activity (p=0,026). The regression analysis showed that the age, as well as the weight of the individuals, have a negative influence over the quality of these parameters. Therefore, aiming to contribute with the development of new reproductive techniques and to improve the spermatic viability, a protocol of sperm selection by Percoll discontinuous gradient was tested. However, even though efficient for gamete isolation from other seminal component, the protocol did not show significant improvement of the parameters, reevaluated after selection, suggesting needing of methodological adequation for and effective application in Leontopithecus chrysomelas. To start investigating the gamete´s epigenetic role in male reproductive success, this essay established a sperm RNA isolation protocol, highlighting the use of seminal clot, a rich source of genetic material, which is usually thrown away after processing. The samples of each individual were condensed in two pools, one referring the clot and other to the liquid fraction. Adaptations for the somatic cellular lyse allowed obtainment of similar profiles between the two portions of the ejaculate. The qualitative profiles for sperm RNA of Leontopithecus chrysomelas indicates low concentration of molecules bigger than RNA, being represented, basically, by little and degraded transcripts due to silencing of gene expression in spermatozoa. The spermatic transcripts have been assigned as the determinant function in reproduction, enrolled with the regulation of female gamete activation and gene expression at the beginning of the embryo development. Furthermore, is has been proposed that the quantity of RNA present in gametes be used as a non-invasive tool for deducing male fertility, since these transcripts reflect on events that occur during cellular differentiation.
Desenvolvimento de materiais para a detecção e degradação do bisfenol A e seus intermediários de reação
(Universidade Federal de São Carlos, 2016-09-29)
Goulart, Lorena Athie
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Mascaro, Lucia Helena
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https://lattes.cnpq.br/9130022476352844
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https://lattes.cnpq.br/5135184611261934
In this study, tungsten oxide and copper composites were developed for making applied anodes in fotoelectrolysis of bisphenol A (BPA) and electrochemical sensors composed of carbon nanotubes (CNTs) and metal nanoparticles (NPM) for the detection of BPA and its reaction intermediates such as hydroquinone (HQ), catechol (CC) and phenol (Phe). The sensors were obtained by casting method on a glassy carbon surface and the quantitation of molecules of interest was carried out by pulsed techniques using the standard addition method. Different methods of functionalization, and the influence of CNTs sizes were investigated for the determination of BPA. CNTs samples with 20-170 nm in diameter were functionalized in HNO3 solution 5.0 mol L-1 solution and sulfonitric (3H2SO4: 1HNO3). The size and functionalization directly affect the oxidation of BPA and smaller diameter CNTs with improved sensitivity and showed the low limit of detection (LOD) of 8.4 × 10-8 mol L-1. The simultaneous determination of HQ, CC, and BPA was made with CNTs sensor modified with nickel oxide nanoparticles (NiO/MWCNT/GCE). The deposition of NiO was made by cyclic voltammetry (CV) and were evaluated the concentration of the nickel solution and the number of cycles. The best results were obtained when NiO was deposited in a solution of 8.0 mmol L-1 Ni(NO3)2 and 40 cycles. The analytical curves showed an excellent linear response and the LODs for the simultaneous determination of BPA, HQ and CC were 2.8 × 10-8 mol L-1, 2.7 × 10-8 mol L-1 and 5.9 × 10-8 mol L-1, respectively. Silver nanoparticles (AgNPs) were also incorporated in the films of MWCNT/GCE by CV. The AgNPs/MWCNT/GCE sensor showed good stability and reproducibility and has been successfully applied to the simultaneous determination of HQ, CC, BPA and Phe in tap water samples. Morphological characterization of the developed sensor was performed by scanning electron microscopy (SEM) and electrochemical characterization was made by CV and electrochemical impedance spectroscopy. Tungsten oxide films doped with copper (WO3-Cu) obtained by the modified sol-gel method were used in the studies photoelectrolysis BPA. The doping with Cu increased six fold the value of the photocurrent density of the material compared to the WO3. The characterization of the synthesized anode was made by techniques of X-ray diffraction, SEM and energy dispersive microanalysis (EDX). The monitoring of the decay of the concentration of BPA and the formation of intermediates generated during the photoelectrolysis was made by electrochemical sensors based on CNTs/NiO and UV-Vis absorption. The results of the total organic carbon content showed 75% of BPA was degraded and it was found that it is possible to monitor the BPA of degradation process and the formation of reaction intermediates using sensors developed in this work.
Modelagem matemática da interação populacional entre Diatraea saccharalis (Fabricius, 1794) e o parasitoide Cotesia flavipes (Cameron, 1891)
(Universidade Federal de São Carlos, 2016-09-29)
Rodero, Donavan Peres
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Colato, Alexandre
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https://lattes.cnpq.br/5460973924624757
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https://lattes.cnpq.br/3358457036811370
The sugarcane borer, Diatraea saccharalis, is one of the major pests in Brazil causing great damage to the crop. Studies estimate that, for each 1% of sugarcane borer infestation, the yield losses will be 1.14%, the reduction in sugar content and ethanol production 0.42% and 0.21%, respectively. Thus, for Brazil meet the growing demand for sugar and ethanol is of paramount importance to enhance the management programs of this pest. For this, new techniques and tools such as mathematical modeling arise to assist producers. The present study aims to describe the interaction between population Diatraea saccharalis and one of its natural enemies, the parasitoid Cotesia flavipes, through mathematical modeling and computer simulation. The Biology and interaction between the two insects were characterized by literature, allowing the development of the model of the predator-prey differential equations (Lotka-Volterra), which was validated by computer simulation. The equilibrium situations and scenarios were influenced by the model coefficients, as well as the variables considered in computer simulation altered the dynamics of interaction, indicating the importance of adjustment for variables for the particular producer's situation. This study allowed a greater knowledge of the interaction between population D. saccharalis and C. flavipes, contributing by simulating scenarios for the definition of pest control strategies in the sugarcane fields.
Análise da dinâmica do programa de aquisição de alimentos no município de Mirante do Paranapanema/SP
(Universidade Federal de São Carlos, 2016-09-29)
Pereira, Elizabeth Lima
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Barone, Luís Antonio
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https://lattes.cnpq.br/7387083975795268
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Montebello, Adriana Estela Sanjuan
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https://lattes.cnpq.br/4326971138357942
The National Program for the Strengthening of Family Agriculture (PRONAF) emerges as a tool to build a new model of rural development in the country, whose main mission is to combat the inequalities that have traditionally marked the state policies aimed at stimulating a change in the technical basis of agriculture. That his institution marks the recognition of family farmers as a social category and opens the way for the implementation of a series of public policies aimed at attending to the world of family agriculture. Among these, the Food Acquisition Program (PAA) was created in 2003 with the purpose of promoting food and nutritional security, linked to the strengthening of family farming. The purpose of this research was to analyze PRONAF, in the period 1999-2012, regarding the distribution and coverage of resources and also to analyze the PAA, in the period of 2011-2014, in the region of Pontal do Paranapanema / SP, with emphasis in the municipality of Lookout. In addition to bibliographical and documentary research, the work used data from the Central Bank of Brazil in the case of PRONAF and the SAGI Platform in the PAA case. In addition, semi-structured interviews were conducted with farmers' organizations, and members of municipal PAA management, as well as application form with farmers providing food in the program. It was verified that, the resources of the PRONAF are strongly significant in few municipalities, highlighting concentration of resources. In the case of the PAA, it has been found that it has contributed to farmers' activities in agriculture, not just in livestock activities, but also before the program. It also influences better feeding of the farmers involved, as well as the families that receive the food purchased by the PAA in the municipality. A sensitive alteration of the productive matrix was observed. The program also made possible, even in a timely manner, investments in productive activities
As relações com saberes de biologia em falas de jovens alunos do ensino médio a partir do ensino de biologia : uma visão sociocultural
(Universidade Federal de São Carlos, 2016-09-29)
Alves, Victor Cherubin
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Sousa, Maria do Carmo de
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https://lattes.cnpq.br/6637658562543505
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https://lattes.cnpq.br/0650896176233057
This research aims to analyze the relationship with knowledge, including biology, that the students explicit in the school context. It is based theoretically in studies of Charlot (2000, 2001, 2005, 2015) that deal with the relationship with knowledge and in studies of Dayrell (1996, 2007, 2010, 2014) who consider the school as sociocultural space. The methodology is qualitative. We used as instrument of data collect semi-structured interviews with the students. Data analysis considered the three themes proposed by Charlot (2000): (a) the relationship of the identity that takes into account the learning process inserted in the history of the student; (B) the social relationship that structures the relationship with knowledge, considering the person as an individual inserted in a broader social history and (c) the epistemic relation to knowledge which defends that learning has different meanings for students, and as the sociocultural issue of school environment and the educational context that they were inserted. The results indicate that the identity construction that the individuals - young students and from the public school - make of themselfs in the world (school, family, society, work), directly influences the epistemic relations in the meaning of learning and consequently in the relationships that they make with biology contents that are build in the school context.
Obtenção de blenda biodegradável PLA: amido para a incorporação do micronutriente manganês
(Universidade Federal de São Carlos, 2016-09-30)
Malafatti, João Otávio Donizette
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Paris, Elaine Cristina
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https://lattes.cnpq.br/8475640212486290
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https://lattes.cnpq.br/9880071190362996
The incorporation of particulate fertilizers in polymeric fibers aims to release these active principles from a substrate with a high surface area and biodegradable and biocompatible properties. It also seeks to provide the release thereof, and minimize the effects of leaching, increasing the efficiency of absorption by the roots in direct soil application. Thus, the present study was to interest obtaining a composite biodegradable matrix of acid poly -L- lactic (PLA):starch in the form of fibers, impregnating particulate solids that can act as sources of manganese ions. It is also aimed to assess any improvement in the release of the Mn2+ ions in an aqueous medium by means of variations in the processing of biodegradable blends. PLA fibers were obtained employing the electrospinning method, various solvent systems primarily been studied for obtaining a polymer solution, in order to obtain the best morphological characteristics for the support, such as control of the fiber diameter and porosity. Then there was the addition of different concentrations of starch in order to find the best embodiment of this condition to the fibers. Finally, we performed the inclusion of MnO, MnO2, MnCO3 and MnSO4, to act as sources of manganese ions, in order to observe possible and different interactions of these with the polymer matrix. In the release test, the same concentration of manganese ions 12.5% (w/v) was added experimentally to a medium extractant citric acid 2 % (w/ w) at 25 ° C in a range of 6 days for all the aforementioned precursors. It was observed that the presence of starch in the PLA fiber increased water vapor permeability (WVP) which promotes the degradation of the blend. The incorporation of salts and oxides in the blends PLA:starch used by the process resulted in different effects of the merger, agglomeration and dispersion in the composite due to its grain size and dispersive characteristics in the solvents used. The behavior of salts and manganese oxides embedded in composite promoted the rapid and direct release of assets. The composites PLA:starch is a polymeric support with high surface area which minimizes the effects of leaching allowing direct release of different precursors ion Mn2 + as fertilizer sources.
Abordagens sintéticas para a funcionalização de novas porfirinas
(Universidade Federal de São Carlos, 2016-09-30)
Barona Castaño, Juan Camilo
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Oliveira, Kleber Thiago de
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https://lattes.cnpq.br/3759761373942891
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https://lattes.cnpq.br/1969014633859806
Herein, we optimized some conditions in the synthesis of a β-octasubstitued porphyrin with electron withdrawing groups (1). This system was used to study the bromination of the meso position aiming at subsequent cross-coupling reactions and meso-functionalization of these porphyrin systems (Scheme 3). The main goal was to obtain porphyrin derivatives with modulations in the UV-visible spectra with potential application as photosensitizers for photodynamic therapy treatments (PDT). We found better conditions for the preparation of the porphyrin 1 changing the formaldehyde precursor from trioxane to dimethoxymethane, and reducing the time of second step in the reaction (oxidation of the porphyrinogen). The yield was increased to 13%. After the optimization of 1, different bromination methodologies were tested in order to obtain the meso-bromoporphyrins 2 or 3; but unsuccessfully. In this perspective, we also proposed the synthesis of β-fused porphyrins with imide moieties (Scheme 4), being the functionalized pyrrole 8 the starting material. Porphyrins 9 and 11 might be alternatives for the preparation of new substituted derivatives via cross-coupling reactions, leading to compounds with different photophysical properties. The synthesis of porphyrin 9 was not succeeded by the approaches adopted here, showing only complex mixtures or total degradation of 8. Furthermore, experiments for the formation of dipyrrolmethane 10 were made without any success, precluding the construction of the porphyrin 11. Certain intermediates of interest could be isolated with relative success, and future explorations will be considered.
Filogenia molecular e filogeografia do gênero Salminus (Characiformes)
(Universidade Federal de São Carlos, 2016-09-30)
Silva, Carolina de Barros Machado da
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Galetti Júnior, Pedro Manoel
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https://lattes.cnpq.br/7398754661670478
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https://lattes.cnpq.br/5400931880079477
Salminus is a genus comprised of four Neotropical medium- and large-sized fishes species, top predators, with both recreational and commercial importance. The paucity of information on taxonomy, phylogeny and phylogeography make appropriate conservation policies difficult for the genus, which is in a significant population decline. For this reason, our goal was, by using mitochondrial (COI, Cytb and D-loop) and nuclear (RAG2 and S7 intron) molecular makers, to elucidate taxonomic uncertainties, identify cryptic diversity, investigate the phylogenetic relationship among the species and infer the historical processes that shaped the current Salminus distribution. To assist in taxonomic issues, we employed the traditional DNA barcoding and GMYC COI-based analyses in 110 specimens, representing the four valid species. In both methodologies, eight MOTUs (molecular operational taxonomic units) were identified. Only two species, Salminus affinis and Salminus franciscanus, represented a MOTU each. The species Salminus brasiliensis and Salminus hilarii were represented by two and four MOTU, respectively. These MOTUs are distributed in distinct hydrographic basins where morphological polymorphisms had already been described. The average intraspecific distances greater than the optimal threshold of 1.1% (S. brasiliensis – 3.6%, e S. hilarii – 5%), reinforce the idea of more taxonomic units in Salminus. The multiloci analysis recovered interesting information about the cryptic diversity: the paraphyletic mitochondrial lineages of S. brasiliensis, one from Upper Paraná river and another composed of specimens from the other regions of the Platina basin, formed a unique monophyletic group. For S. hilarii, despite the four MOTUs observed, only three of them were recovered. Therefore, based on multiloci analysis and phylogenetic species concept, we proposed a new taxonomic scenario for Salminus. The genus is now composed of six species: S. affinis, S. franciscanus, S. brasiliensis, S. hilarii, Salminus sp. Amazonas and Salminus sp. Araguaia. The phylogeny reconstruction refuted hypotheses previously proposed. S. affinis, the only trans-Andean species, was the sister species of the other Salminus, which formed two main groups: Northwest group, composed of S. sp. Amazonas and S. sp. Araguaia, and Southeast group, formed by S. brasiliensis, S. franciscanus and S. hilarii. The divergence processes among Salminus began in Later Miocene and it is associated with vicariance and geodispersion events that shaped the hydrological landscape in the past 12 million years. For the first time, it was used a model-based approach in order to test alternative biogeographic scenarios and to distinguish phylogeography signatures among the events responsible for Neotropical fishes’ diversification. We evidenced that the distinct vicariance and geodispersion signatures could be detected in our biological model. A clear description of these species brings in a valuable information for conservation, because, now, six biological units need to be protected. As these species are located in distinct hydrographic basins, each basin becomes one important biogeographic unit to maintain the evolutionary and ecological processes that sustain the species permanence and diversity.
Zircônia CO-dopada por compensação de cargas nos sistemas (ZrO2)1-(x+y)(InO1,5)x(MOz)y com MOz = TaO2,5, NbO2,5, MoO3 ou WO3, como revestimento para barreira térmica
(Universidade Federal de São Carlos, 2016-09-30)
Piva, Roger Honorato
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Morelli, Márcio Raymundo
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https://lattes.cnpq.br/0172837599844991
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https://lattes.cnpq.br/0515321727144523
InO1.5-stabilized zirconia (InSZ) is a potential hot corrosion resistant thermal barrier coating (TBC). However, the thermal instability prevents real applications of InSZ-based TBC. This thesis investigates the hypothesis of co-doping using the charge compensation to improve the phase stability of InSZ. Four co-doping systems were synthesized by coprecipitation and studied: (ZrO2)1-(x+y)(InO1.5)x(MOz)y with MOz = TaO2.5, NbO2.5, MoO3, or WO3. After synthesis, 9 mol% of InO1.5 plus the charge-compensating oxides was sufficient to stabilize the tetragonal phase. Specific surface area up to 106.1 m2.g-1 and crystallite size ~11 nm were achieved using ethanol washing followed by azeotropic distillation as dehydration technique in the precipitates. In these powders, initial thermal stability analysis indicated instability of the tetragonal phase, with extension of the t→m transformation less detrimental in the InMoSZ system. Further increase in the concentration of InO1.5:MoO3 results in monophasic samples with retention of cubic phase in the InMoSZ. Cubic InMoSZ exhibited hardness and thermal expansion coefficient of 13.5% and 9% higher than those of InSZ, respectively. However, thermal treatments at T ≥ 1200 °C showed that the InMoSZ is also passive to destabilization of the high temperature cubic polymorph. Although the cubic InMoSZ was the most promising system found in this thesis, the stability results do not support its application as TBC for temperatures ≥ 1000 ºC. A deep evaluation of the phase transformations between 1000 to 1200 °C indicated that the instability of the proposed systems is due to a progressive c→t→m destabilization of the polymorphs. This c→t→m transformation is directly associated with the reduction of the InO1.5 stabilizer in solid solution by volatilization as In2O during heat treatment. At temperatures ≤ 800 ºC, the c→t phase transformation do not occurs, then, InSZ-based TBC is stable in these conditions.
O problema pseudoviscoso e a equação de BBM-Burgers estocásticos
(Universidade Federal de São Carlos, 2016-09-30)
Carneiro, Evaneide Alves
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Kondo, Cezar Issao
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https://lattes.cnpq.br/0900348462714778
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https://lattes.cnpq.br/7748150619501176
This work is divided in two parts: In the first part, we study the convergence of a sequence of approximating solutions to a solution of the stochastic conservation law, in the additive and multiplicative case. In the second part, we obtain existence, uniqueness and regularity results to a solution of the Benjamin-Bona-Mahony-Burgers (BBMB) stochastic equation.
Trajetórias e caminhos : uma cartografia dos bebês
(Universidade Federal de São Carlos, 2016-09-30)
Oliveira, Julia Yoko Tachikawa de
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Abramowicz, Anete
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https://lattes.cnpq.br/2502752385941894
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https://lattes.cnpq.br/5130233558284874
This research aimed to trace the movements of the babies through the cartography, considering them protagonists of the traces. Aiming to promote a discussion about the research methodology for studies of babies in their specificities on the spaces they occupy, the work mapped the babies movements and actions daily in a public space, in a collective context of experiences, in an institution of early child education and care. The methodology of research was qualitative approach in the ethnographic type with participant observation, capture of images and records, this documentation and diaries was transcribed in maps accompanied by subtitles and descriptions of scenes. The theoretical framework was based on the Sociology of Childhood, with William Corsaro, with the model of the global web and a cultural routines, and in Fernand Deligny, for a cartography, whose practices of maps were revealed as a form of transcription of the "voices", movements, affections, encounters and not the explanation of the origin or nature of movements or other forms of interpretations about behaviors and standardized actions. The research uses a language for the possibility of indicate some paths and tracks to enlarge our understanding of the " babies world " and looked for knowledge in how works can be as starting points babies participation as sources and informants, to be constitute in a research with babies, not just about babies.
Uso da terra e avaliação da naturalidade para o planejamento e manejo ambiental de bacias hidrográficas (Sudeste do Brasil)
(Universidade Federal de São Carlos, 2016-09-30)
Costa, Rômulo Theodoro
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Fushita, Ângela Terumi
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https://lattes.cnpq.br/1078644223231926
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Santos, José Eduardo dos
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https://lattes.cnpq.br/8533387365058570
Ecosystems managed manifest vulnerability according to decline of ecological resilience and depletion or loss of the main ecosystem service flows. Driving forces acting in landscape result in changes, which require regional management actions and / or local, in conjunction with other external factors. To operationalize these concepts in landscape management, this study approached the dynamics of the intensity changes in land use and conservation conditions of biodiversity scenarios, between 2004 and 2014, for the Jacaré-Guaçu and Jacaré-Pepira watershed rivers. The same analyzes were applied on floodplains formed at the Jacaré-Guaçu and Jacaré-Pepira headwaters in 2004, 2014 and 2015. Conditions of sustainability, involving environmental aspects from the land use and cover dynamic and sustainability indicators were assessed in these areas. Land use and cover dynamics maps were produced based on visual interpretation of Landsat images. Biodiversity conservation scenarios were designed based on Urbanity Index, which estimates the naturalness landscape conditions. The results showed a predominantly anthropogenic scenario, induced by expansion of the agricultural anthropogenic and non-agricultural anthropogenic land uses, and trough conversion of other land use types in sugarcane and forestry. The historical process of land use occupation for agricultural production remains the main driving force of landscape changes, which currently occupies more than 70% of the watersheds area. The Jacaré-Guaçu watershed river presented a critical scenery due to naturalness areas losses and critical naturalness areas increase. The biodiversity conservation scenery showed a reduction area and spatial displacement between 2004 and 2014, resulting from loss and fragmentation of natural capital in the watersheds. Despite the increase in natural vegetation areas, the watershed are far from a sustainable condition, according to loss of carrying capacity and the ecosystem services provision. There was no changes evidenced in land use and cover in floodplains, however, the localization of floodplains showed high vulnerability due to agricultural and urban areas, which indicates evidence of sustainability losses evidences.
Estruturas de copa e raiz de espécies arbóreas do Cerrado nos primeiros anos de crescimento
(Universidade Federal de São Carlos, 2016-10-03)
Silva, Ricardo Rafael Ribeiro da
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Prado, Carlos Henrique Britto de Assis
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https://lattes.cnpq.br/7561749470600567
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https://lattes.cnpq.br/8620290960870650
Tree species of the cerrado vegetation show several degrees of leaf deciduousness such as the deciduous, semi deciduous and evergreen. However, it is not clear if these groups are functional groups. The main objective of this dissertation was to identify sets of characteristics and their compromises in each leaf phenological group that could identify functional groups since the early years of development. By identifying interrelationships of traits, it was possible to established syndromes that could characterize functional groups. We used canopy and root architecture as well as biomass partitioning as sets of traits to identify functional groups. Deciduous showed a relatively more vigorous root system, reaching greater depths, and higher total biomass of fine roots in relation to semi deciduous and evergreen species. There were more biomass of fine roots occupying the upper layers of soil and thick roots in the deeper layers in deciduous species. Additionally, the architecture of deciduous showed longer branches and higher biomass in heterotrophic portion. The leaf phenological groups were separated significantly into three functional groups. Deciduous and evergreen showed contrasting traits. The semi deciduous species usually occupied the intermediate position. By using sets of traits from roots and canopy it was possible to separate significantly deciduous, semi deciduous e evergreen species into three functional groups where leaf deciduousness was just one of several intertwined characteristics in each group.
Determinantes
(Universidade Federal de São Carlos, 2016-10-04)
Prata, Gustavo Gomes
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Costa, Ivo Machado da
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https://lattes.cnpq.br/1111331485581633
This paper wants to provide subsidies to the Mathematics teacher of Basic Education, regarding to Determinants. From a consistent theoretical basis, it builds the concept of Determinant and deducts its main properties. Subsequently, it presents some of its applications, which can be explored in High School, linked to the historical context in which they were developed, aiming to make learning of Determinants more significant. Thereby, the Chapter 1 presents basic concepts of Linear Algebra, which are prerequisites for the definition and study of the Determinant Function, as well as of its properties, which are developed in Chapter 2. Chapter 3, on the other hand, promotes connections of Determinants with other middle-level mathematical concepts related to the own Linear Algebra and Analytic and Euclidean Geometry, each one with a specific historical introduction.
Efeitos de nanopartículas de óxido de cobre (nano-cuo) e cloreto de cobre (cucl2) sobre a composição bioquímica e atividade fotossintética da Clorofícea Raphidocelis Subcapitata
(Universidade Federal de São Carlos, 2016-10-05)
Alho, Lays de Oliveira Gonçalves
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Souza, Jaqueline Pérola de
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https://lattes.cnpq.br/2320506014760329
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Melão, Maria da Graça Gama
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https://lattes.cnpq.br/8342306603661310
Production and utilization of copper oxide nanoparticles (CuO-NP) have increased recently due to their specific physicochemical properties. Most of these nanoparticles end up in aquatic ecosystems, but their effects on the biota were not yet well characterized. The present study aimed to compare the toxicity of CuO-NP and copper chloride (CuCl2) in the microalgae Raphidocelis subcapitata, in order to determine whether the main cause of possible toxicity is due to released copper ions or intrinsic properties of the nanoparticle. We evaluated the effects of these two compounds on several physiological and biochemical parameters of the algae (photosynthetic activity, growth, dry weight, carbohydrates levels, total lipids content and lipid classes). Exponential growth phase algal cultures were exposed during 96 hours to different concentrations of CuO-NP (0.07 to 12.6 μM Cu L-1) and CuCl2 (0.07 to 2.29 μM Cu L-1). The mean inhibitory concentration for R. subcapitata exposed to nanoparticles at 96 h (IC50-96h) was 74 μM Cu L-1, while for CuCl2 was 0.65 μM Cu L-1. There was an increase in dry weight, total carbohydrates and total lipids in algae exposed to the highest copper concentrations in both treatments (salt and nanoparticles), but there was not much change in chlorophyll content after 96 hours of exposure. Concerning lipid composition, sterols (ST) and aliphatic alcohol (ALC) increased under CuCl2 exposure, while aliphatic hydrocarbons (HC) and triacylglycerols (TAG) increased in the presence of nano-CuO, compared to control. The highest concentrations of each compound reduced 36% of algae initial fluorescence (F0) and about 70% the maximum fluorescence (Fm) after 96 hours of metal exposure. Maximum (ɸM) and effective (ɸM ') quantum yields were affected by the two copper compounds, with the largest changes found in the algae exposed to nano-CuO. The major changes observed in the efficiency of oxygen complex evolution (F0/Fv) indicate that this was the main site of action of copper, through changes in the process of water photo-oxidation, especially in algae exposed to nano-CuO. The photochemical (qP) and non-photochemical quenching (qN) were not significantly altered by the metal. We found that CuCl2 was more toxic than nano-CuO in all parameters evaluated, and this can be related to lower free copper ions available in nanoparticles. In this study, we concluded that the two copper compounds significantly affect photosynthetic activity, of R. subcapitata, with more pronounced changes in algae treated with CuO-NP, which may indicate different forms of action between the dissolved copper in the salt and in the CuO-NP. The parameter F0/Fv showed greater sensitivity to copper, being potentially a good tool for research on the physiological stress generated by metals in microalgae.
Paralelos entre a física e a matemática para o ensino de geometria aplicações da interdisciplinaridade como recurso didático
(Universidade Federal de São Carlos, 2016-10-06)
Rodella, Yuri Michelan
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Salvador, José Antonio
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https://lattes.cnpq.br/2487171069472158
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https://lattes.cnpq.br/7356239490836027
Correlações entre parâmetros microestruturais, parâmetros térmicos e resistência mecânica de ligas Sn- Bi e Sn-Bi-(Cu,Ag)
(Universidade Federal de São Carlos, 2016-10-07)
Silva, Bismarck Luiz
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Spinelli, José Eduardo
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https://lattes.cnpq.br/8882038118634925
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https://lattes.cnpq.br/4377238190630005
The present research aims to develop a theoretical/experimental analysis of the combined effects of solidification thermal parameters, Bi content and addition of ternary elements (Cu, Ag) on the final microstructure aspects and on the final mechanical resistances of directionally solidified Sn-Bi, Sn-Bi-Ag and Sn-Bi-Cu solder alloys under transient heat flow conditions. Hence, experimental interrelations between microstructure and thermal parameters and between mechanical properties and microstructure could be established. The microstructures regarding the Sn-34wt.%Bi and Sn-52wt.%Bi alloys show the presence of β-Sn dendrites with Bi precipitates on their own, being enveloped by a lamellar binary Sn-Bi eutectic. The Sn-58wt.%Bi eutectic alloy show a variety of microstructures along the length of the directionally solidified casting, which includes binary eutectic, Bi plates, Bi trifoils and fishbone eutectic. In the case of the ternary Sn-Bi-Ag and Sn-Bi-Cu chemistries, microstructures are constituted by β-Sn dendrites decorated with Bi particles, Bi-Sn eutectic and Cu6Sn5 and Ag3Sn intermetallic particles for the Cu and the Ag bearing alloys, respectively. Experimental growth laws have been derived for both dendritic (λ1, λ2, λ3) and eutectic (λfine, λcoarse) arrangements considering the following alloys: binary Sn-34wt.%Bi, Sn-52wt.%Bi e Sn-58wt.%Bi alloys and ternary Sn- 34wt.%Bi-0.1wt.%Cu, Sn-34wt.%Bi-0.7wt.%Cu e Sn-33wt.%Bi-2wt.%Ag. Considering the binary Sn-Bi, it has been observed that increasing Bi content (34wt.%-->52wt.%-->58wt.%Bi), may cause a decrease on both strength and ductility, except for the sample at P=6mm of the Sn-52wt%Bi alloy. Hall-Petch type functional correlations have been able to represent the evolution of the tensile mechanical properties for the examined Sn-Bi and Sn-Bi-X alloys.
Obtenção e caracterização de heteroestruturas epitaxiais magnetoelétricas de [KNbO3]0,9-[BaNi1/2Nb1/2O3-𝛿]0,1 e [La0,7Sr0,3MnO3]
(Universidade Federal de São Carlos, 2016-10-07)
Lopez, Andrea Naranjo
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Venet, Michel Zambrano
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http://lattes.cnpq.br/4256279833398263
;
Cardoso, Claudio Antonio
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https://lattes.cnpq.br/0332061570052918
Magnetoelectric materials have been extensively studied in the last decade, particularly due to the applicability for sensors, attenuators, transformers and others. Hence as an objective for this work we propose a study on the fabrication and characterization of materials that may be used as extrinsic magnetoelectrics. Our proposal consists in producing by pulsed laser deposition bilayers of ferroelectric thin films [KNbO_3]_(0,9)-[BaNi_(1/2)Nb_(1/2)O_(3−𝛿)]_(0,1) (KBNNO), grown on magnetic thin films [La_(0,7)Sr_(0,3)MnO_3] (LSMO). Focusing our interest on the KBNNO, because it is a relatively new material, and there is not enough information about its possible applications as magnetoelectric, just as there are for photovoltaic application. Initially, we made a detailed study on the dependence of the ceramic target densification of the ferroelectric phase KBNNO with the sintering temperature, with the aim to determine the appropriate parameters in the fabrication of the ceramic target, obtained by solid state reaction method. It was possible to achive ceramics targets with relative densities greater than 94 %. The structural and morphological properties of the ceramic targets and thin films were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The X-ray diffraction profile confirmed the phases and crystal structures of the samples. Particularly, the thin films showed an oriented growth (epitaxial) with formation of nanopilares with different diameters and heights depending on the deposition parameters. The electrical properties were determinated by ferroelectric hysteresis and electric impedance spectroscopy. The magnetoelectric and optical properties were determined by magnetoelectric coupling and photoluminescence measurments, respectively. For the ceramic samples the ferroelectric and dielectric behaviors were confirmed, and for the thin films a magnetoelectric coupling between the ferroelectric and magnetostrictive phases was found. Finally, the value of the gap for ceramic KBNNO was found to be aroud 1.248eV, this result is consistent with values reported in the literature for this material.