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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; Mascaro, Lucia Helena; https://lattes.cnpq.br/9130022476352844; 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.
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; Valle, Rodrigo Del Rio do; https://lattes.cnpq.br/2879780464444096; Peripato, Andréa Cristina; https://lattes.cnpq.br/0657713343451089; https://lattes.cnpq.br/9008338904998266
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.
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; Barone, Luís Antonio; https://lattes.cnpq.br/7387083975795268; Montebello, Adriana Estela Sanjuan; https://lattes.cnpq.br/4326971138357942; https://lattes.cnpq.br/0223121332945117
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; Sousa, Maria do Carmo de; https://lattes.cnpq.br/6637658562543505; 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.
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; Colato, Alexandre; https://lattes.cnpq.br/5460973924624757; 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.