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Modelagem e meta-heurísticas para o problema de roteamento de veículos com janelas de tempo, múltiplos entregadores e múltiplas viagens em uma empresa de distribuição de bebidas
(Universidade Federal de São Carlos, 2016-03-21) Souza Neto, José Ferreira de; Pureza, Vitória Maria Miranda; https://lattes.cnpq.br/9202201560058916; https://lattes.cnpq.br/3342241546549286
Vehicle routing problems occur in many practical situations where the pickup and/or delivery of goods is required. In this context, the present research aims to contribute to the study of logistic operations that arise in companies that deliver products on a regular basis to customers in densely populated urban areas. The problem consists in designing minimal cost daily routes serving the maximal number of customers. To this end, the crew of each vehicle comprise multiple deliverymen as means to reduce service times. Based on a case study in a drinks producer and distributor in the state of São Paulo, it is proposed a mixed integer linear programming model that comprise costs with own and chartered vehicles and the number of deliverymen, and various operational constraints such as time windows in customers, multiple daily trips, time limitations for the circulation of some vehicle types in specific areas, compatibility between vehicles and customers, maximum load in each vehicle, maximum route time and minimum load for the realization of a second trip. Results obtained by solving the model with real instances through exact (branch&cut), heuristic (constructive, local search, GRASP and Simulated Annealing) and hybrid (GRASP and branch&cut) approaches demonstrate the good quality of the generated solutions, and indicate the potential of application of some of these methods in practice.
Efeitos dos agrotóxicos diuron e carbofuran, isolados e em mistura, sobre organismos aquáticos e avaliação de risco ecológico
(Universidade Federal de São Carlos, 2016-03-21) Mansano, Adrislaine da Silva; Rocha, Odete; https://lattes.cnpq.br/7577441794992601; Seleghim, Mirna Helena Regali; https://lattes.cnpq.br/5998337634888263; https://lattes.cnpq.br/0101649577482109
The aim of this study was to evaluate the effects of diuron and carbofuran, isolated and mixed, on Raphidocelis subcapitata, Paramecium caudatum and Ceriodaphnia silvestrii and carry out a preliminary risk assessment of these pesticides for Brazilian water bodies. For this, acute and chronic toxicity tests were performed with individual compounds and in combination, in its standard form and commercial formulations. The results showed that in individual action, these pesticides significantly inhibited the R. subcapitata population growth and caused physiological (chlorophyll a content) and morphological (complexity and cell size) changes in the cells. For this alga, the toxicity of standard active ingredients and their commercial formulations showed no significant differences. For the protozoan P. caudatum, acute toxicity tests evidenced an increase of mortality with increasing exposure time for the selected compounds. Moreover, these pesticides caused a significant decrease in population growth, number of generations and biomass of P. caudatum. The toxicity of standard diuron and its commercial formulation was similar for this protozoan, while commercial carbofuran was more toxic than its standard form, suggesting a synergistic interaction with “inert” ingredients. In contrast, for the cladoceran C. silvestrii, acute toxicity tests showed that diuron commercial product was 7.2 times more toxic than its standard active ingredient, whereas for carbofuran, commercial product was 1.5 times less toxic than its standard active ingredient. Regarding chronic toxicity of diuron herbicide, both standard and commercial form caused hormetic effects on fertility of C. silvestrii female. Carbofuran significantly reduced the reproduction of C. silvestrii at concentrations from 0.38 μg L-1 onwards. The tropical species C. silvestrii was more sensitive to these pesticides than cladocerans commonly used in temperate regions, and in addition, for carbofuran, this species was the most sensitive organism already tested (EC50-48h = 0,86 μg L-1). According to the toxicity tests results of diuron and carbofuran mixtures, acute and chronic exposures on all selected test organisms caused significant deviations from the toxicity predicted by Concentration Addition and Independent Action reference models. For P. subcapitata, data indicated the occurrence of synergism in the mixture of these compounds, especially when diuron is the dominant chemical in combination. For P. caudatum, dose ratio dependent deviation (synergism caused by carbofuran and antagonism caused by diuron) was observed in acute exposure and deviation for antagonism was verified for population growth at sublethal concentrations of the standard compounds mixtures. For C. silvestrii, antagonism was observed in low doses and synergism at high doses, predominating synergism in acute exposures of standard pesticides mixtures, while for reproduction the deviation for antagonism was found. The commercial product mixtures of diuron and carbofuran showed significantly different effects and more severe than the standard compounds mixtures for P. caudatum and C. silvestrii. Therefore, diuron and carbofuran mixture can interact and cause toxic responses different from those predicted for individual compounds. According to the concentrations found in water bodies in Brazil, these compounds can cause direct and indirect toxic effects on communities of algae, protozoa and cladocerans and may change the structure and functioning of aquatic ecosystems. In a preliminary risk assessment of these pesticides, risk quotients were larger than 1, indicating that diuron and carbofuran represent potential ecological risks to Brazilian water bodies. Given the above, it is concluded that the pesticides studied alone and in combination, caused toxicity to test organisms and represent potential ecological risk for aquatic environments, which suggests the implementation by the regulatory agencies of more stringent measures for the use of pesticides to improve the protection of aquatic biota.
Blenda de Polihidróxibutirato(PHB)/Copoliéster Alifático Aromático (AAC) Ecoflex® reforçada com nanofibras de celulose (NFC): análise da resistência mecânica e propriedades químicas
(Universidade Federal de São Carlos, 2016-03-21) Raimundo, Ivan Freitas; Menezes, Aparecido Junior de; Botaro, Vagner Roberto
Due to increasing use of polymeric materials in society and the large volume of of those materials disposal in nature, the biodegradable polymers have increased interest in research of materials area. The Polyhydroxybutyrate (PHB) is a biodegradable polymer used in this work for preparation of a blend with other biodegradable polymer, the aromatic aliphatic Copoliéster (AAC). The central idea was to obtain a material that maintain good mechanical properties due to resistance of PHB and flexibility of the AAC. The percentages reasons in mass of PHB:AAC used for the prepration of physical mixture were 90:10, 80:20 and 95:5. The blends preparation has employed in a first step a solubilization process using chloroform as solvent and after thermoforming process as final preparation step. Some blends were reinforced with cellulose nanofibers extracted from bamboo (NFC) to form a composite. Some techiniques were used to determine the properties of the blend: analysis of FTIR, SEM, DMTA and optical microscopy. DMA tests in tensile module have shown that the blend offers interesting properties, such as increased flexibility of some blends when compared to the PHB without significant decrease in mechanical strength. The images obtained in SEM showed that there is interaction between the phases present in the blend and that this interaction benefits the miscibility, however the increase in composition of Ecoflex in the blend results on phase separation which can cause changes in the mechanical and chemical properties. The results obtained by DMA analysis on flexural modulus and also the DSC analysis have showed important informations about the the miscibility of blends and the relation of miscibility and temperature. For the composites it became evident that the addition of nanofibers have occasioned in 10 to 15% change in the values of the storage and loss module, making the more rigid material when compared to the bends
Hábitos alimentares e conservação do lobo-guará (Chrysocyon brachyurus) (Illiger, 1815) em um remanescente de Cerrado em Pirassununga – SP
(Universidade Federal de São Carlos, 2016-03-21) Müller, Samara Thays Moreira; Rocha, Vlamir José; https://lattes.cnpq.br/8044368595391973; https://lattes.cnpq.br/0564701870794442
The Brazilian Cerrado, the second largest biome in the country, holds a high diversity of species. An important remnant is located at the Air Force Academy (AFA). Previous to this project, no biological studies had ever been carried out on AFA grounds and collecting extensive data in this area will be crucial for its conservation. An important step is to gather knowledge about species of conservation interest such as the maned wolf (Chrysocyon brachyurus), which is considered both a key-species and a flagship species for the Cerrado. It is estimated that over 90% of the maned wolf’s world population lives in Brazil, where the species is considered threatened and classified as “vulnerable”. Therefore, the protection of this species must be a priority in conservation projects in the country. It is also necessary that conservation efforts include a new way of looking at environmental challenges, in which humans are considered an integral part of the environment. The involvement of local communities can be decisive in the success or failure of conservation programs. In order to contribute to the conservation of the Cerrado, this project sought to verify the occurrence of the maned wolf in the Cerrado fragments at AFA and study the feeding habits of this species through the analysis of fecal samples. In addition, we tried to understand the perceptions of the workers at AFA regarding the Cerrado fragments and their associated wildlife, as well as the relationships between these people and the natural areas. The diet of the maned wolf was studied through the analysis of 61 fecal samples collected from October 2014 to September 2015. By frequency of occurrence, the queen palm coconut, arthropods and the wolf’s fruit were the most consumed items. Queen palm coconut, armadillos and lizards provided most of the consumed biomass. The niche breadth calculated through the standardized Levins’ index was 0,29 and chi-square and G tests showed there is seasonality in the diet. Our findings support the view that maned wolves are omnivorous. The items consumed were similar to the ones found in studies in more pristine areas, but there was a variation regarding the relative importance of food categories. The queen palm coconut and Arthropods were more frequent than in other studies, while birds, rodents and reptiles were found in smaller numbers. We investigated the perception of the personnel from AFA towards the Cerrado through the analysis of 40 semi structured interviews. The results indicate that most people do not have any knowledge regarding the fragments. This lack of knowledge is directly related to the attitudes that people have towards the Cerrado: most participants reported that they don’t feel any kind of connection with the biome. Finally, using the principles of critical environmental education as reference, we suggest a series of activities that can be employed to transform the relationship of these people with the environment. We emphasize that more studies should be done in this area, to which there is little information.
Valores de vitamina D e irisina e sua correlação com a composição corporal em crianças com adrenarca precoce
(Universidade Federal de São Carlos, 2016-03-21) Furino, Vanessa de Oliveira; Germano, Carla Maria Ramos; https://lattes.cnpq.br/1685750854841732; https://lattes.cnpq.br/5406611490052377
Introduction: Premature adrenarche (PA) is characterized by the appearance of pubic hair and/or axillary, acne and body odor before age 8 in girls and before 9 in boys and these individuals are at increased risk of developing metabolic syndrome (MetS). Vitamin D and irisin seem to have an active role in the metabolism of carbohydrates and lipids, however, little is known of the role of these hormones in the PA. Objective: To analyze the vitamin D and irisin levels in children diagnosed with PA and the relationship of these substances with body composition of these children. Methodology: a quantitative exploratory cross-sectional study that evaluated 15 children diagnosed with PA and 15 controls (C) matched recruited in the public health of the city of São Carlos, Brazil. Anthropometric data were analyzed: height, weight, waist circumference (WC), triceps skinfold thickness (TSF), systolic blood pressure (SBP) and diastolic blood pressure (DBP). The participants did tests of FSH, LH, testosterone, estradiol, blood glucose, insulin, 17OHP, total cholesterol (TC), LDL, HDL, triglycerides (TG), S-DHEA, 25(OH)D and irisin. Data analysis was performed using the GraphPad Prism 5 program. The paired Wilcoxon test was used to assess the difference between means and the correlation through the Spearman test, with 5% significance level. Results: There was no significant difference between the C and PA groups in anthropometric data. The TG levels (99 ± 14.8 mg/dl in the children C versus 68 ± 9.1 mg/dl in children with PA) (p= 0.0233) and 25(OH)D (26 ± 0.9 ng/ml in the children C versus 30.2 ± 1.6 ng/ml in children with PA) (p= 0.0307) significantly were different between groups. In group C the variable that correlated significantly with irisin was 25(OH)D (r= -0.9358); in the PA group: LDL (r= 0.5620), 17OHP (r= 0.6014), TG (r= 0.6434), insulin (r= 0.5998) and relationship glucose/insulin (r= -0.7033). In group C the variable that was significantly correlated with vitamin D was irisin (r = -0.9358); there was no significant correlation of variables with 25(OH)D in the AP group. Discussion and Conclusion: This study showed higher percentage of individuals with hyperinsulinemia, insulin resistance and CA high in the PA group, important markers of MetS and future cardiovascular disease. An innovative result of this study was the strong negative correlation between irisin and 25(OH)D found in C children, suggesting an interaction of these two hormones in these individuals, which may be related to compensatory modulation of irisin in response to changing metabolism lipid found in this group. In children with PA, the highest correlation of metabolic parameters with irisin may represent a physiological modulation of this hormone by elements related to carbohydrate metabolism (as in control children C) and a specific modulation in PA, due to the same pathophysiological mechanisms that result in unfavorable metabolic profile. Since the PA can lead to an increased risk of cardiovascular disease, these children must have a suitable and long-term clinical follow-up.
Variabilidade genética em populações de Virola surinamensis (Rol. ex Rottb.) Warb. (Myristicaceae): uma espécie ameaçada da Amazônia
(Universidade Federal de São Carlos, 2016-03-21) Corrêa, Aparecida Juliana Martins; Piña-Rodrigues, Fátima Conceição Márquez; https://lattes.cnpq.br/1475369713141675; https://lattes.cnpq.br/4940603316970363
Virola surinamensis (Rol. ex Rottb.) Warb. é uma espécie dioica e ameaçada de extinção, dado o seu alto valor comercial. O objetivo deste trabalho foi determinar se as consequências da atividade exploratória podem ter acarretado em perdas de diversidade genética nas populações estudadas na Amazônia paraense. Foram feitas amostragens para os indivíduos adultos em quatro localidades, avaliando-se a estrutura genética, com 136 indivíduos, em nove populações; e a estrutura da população por meio de inventário, em 12 populações. Foi realizada a genotipagem para oito locos microssatélites para a avaliação da diversidade e estrutura genética espacial, divergência entre populações e coeficiente de coancestria. No inventário, os indivíduos foram analisados segundo a distribuição diamétrica, de altura e espacial para avaliar a intensidade exploratória. Os resultados genéticos apontaram que as nove populações foram polimórficas para os locos utilizados, no entanto, com excesso de homozigotos, com alta heterozigosidade esperada (0,896) e baixa heterozigosidade observada (0,374). A diversidade genética está contida muito mais dentro (0,918) do que entre (0,017) as populações. A estrutura genética espacial intrapopulacional foi decorrente do cruzamento entre indivíduos aparentados, equivalente à primos de primeiro grau e meios irmãos, confirmados pela presença de poucos adultos e muitos jovens agregados entre si nas populações. No inventário, houve diferença entre as regiões estudadas quanto à distribuição diamétrica (Cametá e Cotijuba), mas não com relação à distribuição de altura; todas as populações apresentam algum grau de agregação, no entanto, as populações de Cotijuba foram altamente agregadas, segundo o índice de Green (IG = 0,7 a 0,9). Dadas as condições das populações estudadas, houve perdas de diversidade genética decorrentes da atividade extrativa em consequência da própria ecologia da espécie.
Metodologias de síntese e modificações estruturais em meso-Tetraarilporfirinas
(Universidade Federal de São Carlos, 2016-03-21) Momo, Patrícia Betoni; Oliveira, Kleber Thiago de; https://lattes.cnpq.br/3759761373942891; https://lattes.cnpq.br/7510519147041551
In this thesis we describe studies towards the synthesis of porphyrins aiming the optimization of literature protocols leading to more environmental friendly approaches. Also, structural modifications and photophysical evaluations in meso-tetraarylporphyrins were studied, especially in mesotetra(thien-2-yl) porphyrins. Classical synthetic methods for porphyrins involve the use of high temperatures, toxic solvents, high dilution, and often low yields. In view of this, we decided to explore the methodology described by Bonar-Law in order to verify the feasibility of using aqueous environments in the synthesis of porphyrins. Some modifications were studied using sodium dodecylbenzylsulfonate (SDBS) as a critical micelle-forming instead of sodium dodecyl sulfate (SDS) as previously described, and the use of trichloroisocyanuric acid as oxidizing agent instead of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and montmorillonite K-10 as catalyst instead of HCl. These were chosen in order to use reagents with less environmental impact. However, the results were not satisfactory, yielding amounts of side-products reported in the literature. Also, we have studied the synthesis of porphyrins under continuous flow conditions, since the use of this technology gives more safety and efficiency to chemical reactions. The experiments under continuous flow conditions were performed using an adaptation of Gonsalves and Lindsey methodologies. First, the synthesis of tetraphenylporphyrin (TPP) was optimized, and different flow, temperature and concentration of reagents were evaluated in order to obtain the best reaction conditions. Thus, under continuous flow conditions employing tubular reactors (adaptations Gonsalves methodology), the highest yield for mesotetraphenylporphyrin (TPP) was 31% using a concentration of 0.2 mol L-1 for the pyrrol, and benzaldehyde, a flow of 0.6 mL min-1 at 140 °C. For comparison, the same experiment performed in batch resulted in 25% yield for TPP. Moreover, streaming technology has enabled the synthesis of various meso-substituted derivatives in yields of 9% to 39% indicating good versatility of this tool. The use of solid phase reactors (Lindsey methodology adaptations) consisted of preliminary experiments should be explored in more detail and will be carried on by the research group. With regard to meso-tetra(2-thienyl)porphyrins, these exhibit unique photophysical, photochemical and electrochemical properties and have been identified as potential photosensitizers for photodynamic therapy (PDT) and solar cells (CS) applications. In view of this, we decided to study different conditions for the synthesis, structural modification and the photodynamic properties of these porphyrin derivatives. Meso-tetra(2-thienyl)porphyrin was successfully synthesized using different methodologies with improvements in the yields after experimental modifications of the literature procedures. After systematic studies, meso-tetra(thien-2-yl)porphyrin was obtained in pure form with 36% yield, using chlorobenzene as solvent, hydroxylamine hydrochloride as catalyst and nitrobenzene as oxidant. Nitration reactions were carried out using mild reaction conditions with sodium nitrite and trifluoroacetic acid. The nitrated derivatives were obtained at α-position of thiophene in 66% yield for the mono-nitro product and 59% for the tetra-nitro product. Also, the Vilsmeier-Haack reaction was studied for obtaining functionalized meso-tetra(2-thienyl)porphyrins with formyl groups. In these studies only formylations at the α-position of the thiophene ring were observed, and no formylation at the β position of the porphyrin core (common for tetraphenylporphyrins). Moreover, we obtained reaction conditions in which only mono-formylated product was formed (10%), or only the tetra-formylated product (10%), as well as experimental conditions that yielded different products (mono, di, tri and tetra -formylated). After obtaining the desired formylated product, we studied the application of mono-formylated product in Wittig reaction, Peterson olefination and condensation with 4,4-difluoro-4-bora-3a, 4adiaza-s-indacene (BODIPY ). The latter studies were only an initial exploration and still require further elaboration. Porphyrin derivatives as 2-thienyl-chlorins and 2-thieny- bacteriochlorins were obtained by cycloaddition reactions with nitrile oxide 1,3-dipole with good yields. Also, preliminary photophysical studies of these compounds were performed in order to evaluate the potential of these photosensitizers as photoactive dyes. The photophysical results indicated that the obtained compounds are good producers of oxygen, present good photo-stability and did not undergo aggregation in the studied concentration range. Therefore, the 2- thienyl-chlorins and 2-thienyl-bacteriochlorins obtained in this study showed promising characteristics for use as photosensitizers in photodynamic therapy. Finally, the new heterocycles herein obtained presented bathochromic shift of the absorption bands in the electromagnetic spectrum, since molecules having this characteristic represent high interest in chemical photosensitizers.
Problemas elípticos não lineares envolvendo equações do tipo Kirchhoff
(Universidade Federal de São Carlos, 2016-03-21) Guimarães, Mateus Balbino; Rodrigues, Rodrigo da Silva; https://lattes.cnpq.br/9606661651573155; https://lattes.cnpq.br/2453670728817949
In this work we study the existence of weak solutions for four nonlinear elliptic problems of Kirchhoff type. These problems have in common the presence of a function M : R+ [ f0g ! R+; known as Kirchhoff-type function. The first problem deals with a Kirchhoff type equation involving subcritical exponents while the second problem deals with the same equation but with a critical Caffarelli-Kohn-Nirenberg exponent. In the third problem, we study a system of Kirchhoff type equations involving critical Caffarelli-Kohn-Nirenberg exponents. The latter problem involves a Kirchhoff type operator and a nonlinear boundary condition. Due to the presence of the Kirchhoff type operator in the equations, these problems are called nonlocal problems. This phenomenon causes some mathematical difficulties, which makes the study of such a class of problem, particularly interesting. In our studies we used classical variational methods such as The Mountain Pass Theorem and the Krasnoseslkii genus theory.
Desenvolvimento de modelos de calibração multivariada em espectroscopia de infravermelho próximo para ácidos graxos em amostras de carne bovina
(Universidade Federal de São Carlos, 2016-03-21) Sousa, Jonas da Silva; Nogueira, Ana Rita de Araújo; https://lattes.cnpq.br/7034773971317045; https://lattes.cnpq.br/2951108546726718
The Brazilian cattle have shown promise prominence in the international market compared to other commodities. It already knows the important role of fatty acids in the complimentarily of human nutrition. On the other hand, studies have linked the consumption of beef with increasing rate of diseases associated with high levels of "bad" cholesterol (LDL) in the blood. Because of these two aspects on the topic meat (nutritional value and human health), it is seen necessary to determine the levels oftrans fatty acids in meat. Among the methods for analysis of total lipids and lipid profile, stands out the extraction of fat and chromatography, respectively. In this project was proposed to develop multivariate calibration models for the analysis of total lipids and lipid profile with the use of near-infrared spectroscopy in beef samples which the levels were previously determined. Eighteen properties were analyzed, including: total lipids and myristic fatty acids, pentadecylic, palmitic, margaric, stearic, palmitoleic, oleic, elaidic, linoleic, α-linolenic and families of fatty acids with branched, saturated, monounsaturated (cis), conjugated linoleic (cis, trans), and omega 3 and 6 polyunsaturated. We used 127 bovine meat samples from the calibration steps and internal validation (2/3 to 1/3 calibration and validation for internal and 32 external validation samples. We used the PLSR method for the construction of multivariate models. Flesh spectra were extended from 1111 to 1937, and from 2016 to 2500 nm regions, and regions concerning water and noise judged as interfering in the calibration process were removed during the models construction. We evaluated the performance of the models based on the applied pre-treatments (smoothing, first derivative Savitzky-Golay, SNV), the number of latent variables, consistency, SEC, SEP and determination coefficients (R2 cal/val). The models chosen as having better predictive capacity were those of total lipids, myristic acid, palmitic acid, margárico and saturated fatty acids, demonstrating that the NIRS has a high potential for the quantification of lipid constituents of the beef.