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O Cio da Terra: diálogos entre música caipira e globalização
(Universidade Federal de São Carlos, 2017-12-18) Pereira, Synclair Antonio Vieira; Mariano, Neusa de Fátima; https://lattes.cnpq.br/5003743301847104; https://lattes.cnpq.br/3973353251484647
Music, sometimes neglected in the human sciences, is one of the ways in which space, Geography’s object of study, can be analyzed, allowing new possibilities of comprehension of the reality. This work, studying the lyrics and the structure of Brazilians music genres caipira and sertanejo, through evolution processes of themselves in time, seeks to understand how music consume and production happens in Brazilian space in face of globalization. Based in the relation between both musical genres, we seek to understand the contradictions between rural and urban space, as well as local and global space.
Inimigos naturais na restauração florestal
(Universidade Federal de São Carlos, 2017-12-18) Ferreira, Rafael Borrasca; Fujihara, Ricardo Toshio; https://lattes.cnpq.br/1863735094370774; Viani, Ricardo Augusto Gorne; https://lattes.cnpq.br/3250752369062840; https://lattes.cnpq.br/9113775092468163
Forest restoration is a global priority by make the reestablishment of ecosystem services. Many of these services have major importance on the agriculture fields, such as the pest control given by the predators and parasitoids fauna. In the search for a better understanding of the relation between natural pest control and the forest restoration, we aimed to: i) verify if the restoration process can increase the abundance, richness and diversity of natural enemies; ii) verify if these increases are exclusive to natural enemies or occurs with others arthropods; iii) compare attributes from the vegetation structure and the natural enemies community. The study was carried out in two different landscapes in São Paulo state, Araras and Itu. In each landscape, we selected a pasture, a younger, an intermediate and an older restoration planting, and a forest fragment. In September and October of 2016, five plots of 10x10m we replaced in each area for measuring tree density, sapling density and canopy cover. A pitfall trap was placed in the center of each plot for the passive arthropod survey and we used the beat sheet in the four trees nearest to the center of the plot for an active arthropod survey, we performed these surveys two times, one in the dry and the other in the rainy seasons. The richness and diversity of natural enemies enhanced by the process of restoration, and this enhance was higher for natural enemies than to arthropods in general. The abundance of natural enemies of restoration sites shows no difference to pastures and forest patches, but pasture shows less abundance than the forest, we didn’t found difference in the abundance of natural enemies and the other arthropods though this restoration chrono sequence. Canopy cover and tree densities were positively correlated to richness, diversity and abundance of natural enemies, showing that the forest structure reestablishment in the restoration areas can enhance the natural enemies community.
Proposta de um modelo para refeições digitais
(Universidade Federal de São Carlos, 2017-12-18) Leandro, Sandra Maria; Pessoa, José Dalton Cruz; https://lattes.cnpq.br/4212703554284544; https://lattes.cnpq.br/2434970483997012
Innovation is an imperative demand in the food sector, since the segment needs to respond quickly or even anticipate the new demands of consumers. Additive manufacturing food is a disruptive approach that allows to create personalized foods, introducing convenience and practicality. The problem that motivates this research is to answer the following question: "how to define a digital food?". Digital foods correspond to a field of knowledge under construction in the scientific literature. Consequently there is a need to create terminologies and a model to systematize some concepts. In order to fill this gap, this thesis proposes a digital food model that includes the sensorial, organoleptic and nutritional specifications of the individual. Some common cooking materials are also analyzed to identify the possibilities and limitations of solid freeform fabrication (SFF). From these analyzes is proposed a printer for foods and an interface for mobile devices, tablets and smartphones, able to simulate the steps that define and precede the customization of a digital food. The evaluation of results indicates that additive manufacture food can exert significant influence on individuals by introducing new designs, textures, flavor, colors and personalized eating experiences. Digital foods will not solve all nutritional and does not replace the existing food processing techniques, but tend to complement the daily intake.
Trajetórias acadêmicas de pessoas com deficiência no ensino superior brasileiro
(Universidade Federal de São Carlos, 2017-12-18) Morgado, Liz Amaral Saraiva; Orlando, Rosimeire Maria; https://lattes.cnpq.br/4254571422608459; https://lattes.cnpq.br/4792151711883696
The research had as main theme the access and permanence of students with disabilities in Higher Education Institutions (HEI) as well as the investigation of how the students' academic trajectory and the impact within the institutions occur. The objects were to analyze the educational trajectory of people with disabilities in Brazilian Higher Education; to describe the conditions of access and permanence of persons with disabilities in Brazilian Higher Education; to indicate, within the academic trajectory, the conflicts in the political construction of accessibility; to verify the restructurings caused by the policies related to the access of people with disabilities in Brazilian Higher Education. The study was of qualitative character. The data were collected through semi-structured interviews. Participated in the research nine subjects who were contacted and selected previously. The data were analyzed and divided into three categories: i) access and permanence in Higher Education with four subcategories: selective process, affirmative actions, sports and supports; ii) Restructuring of Higher Education Institutions with the presence of people with disabilities and iii) accessibility groups. The results of the research demonstrated a great necessity to ensure adequate educational care for the access and permanence of students with disabilities at the University. The institution needs to promote more directive policies for the inclusion of the person with disabilities in the academic environment.
Uma heterotopia pedagógica : práticas bilíngues com alunos surdos em salas multisseriadas
(Universidade Federal de São Carlos, 2017-12-18) Almeida, Júlia Caroline de Araújo; Martins, Vanessa Regina de Oliveira; https://lattes.cnpq.br/4768682330164550; https://lattes.cnpq.br/1369122714639837
From the concept of resistance coined by Michel Foucault, and also, by the configuration of new fields of knowledge in the education of deaf people with the emergence of cultural perspective, the present work had as main objective to analyze pedagogical practices of bilingual teachers working in multi-serialized that has the Libras (Brazilian Sign Language) as the language of instruction in schools located in two municipalities in the state of São Paulo. Inside the work will be presented the configuration of the multi-series deaf classrooms, differentiating them from the old special classrooms. Observed classrooms have deaf students inserted into a bilingual inclusive educational proposal - schools that have adhered to this format have been nominated as bilingual inclusive schools. There were several concerns that guided this work, which are intended to respond to the end of the work. Among them: Can the "Language of Education" rooms (or multisseries of deaf people) be characterized as heterotopic spaces, loaded with resistance to the educational system that govern them?For the teachers working in these classrooms, what are the biggest challenges and how do they consider that they resist the impositions of the teaching system that govern them and re-signify their pedagogical practices? And yet, how much has Libras been, in fact, language of instruction and composed new practices, plural and resistive in the common school? For that, a qualitative research was developed with investigative proposals of the school routine, therefore, a field research. Observations were made about the daily life of these classrooms and about the performance of teaching, as well as interviews with participating teachers to better understand the educational process and concerns about the study. The everyday research brings with it a unique way of searching and problematizing, with specific procedures that emerge in the act of entering the researcher with the place to be researched. It allows a more cohesive analysis of the field being studied and allows the use of several instruments for data collection. In this study, observation was used with records in field diaries and interviews. The challenge was to articulate the genealogical methodological procedure, based on Foucault concepts and its articulation with everyday research. We conclude that the multisseries rooms analyzed, plural and at the same time singular, are heterotopic spaces, loaded with resistance and the militant action of the teachers participating in this study makes possible an education other to these students. The reading of this work, therefore, intends to contribute with educators who also work with deaf students, constantly resist and seek to re-significate their practices always considering the singularities of their students in the educational process.
Proposta para o ensino de frações para o 7 ano: do diagnóstico à aprendizagem mediada por Modelo de Barras
(Universidade Federal de São Carlos, 2017-12-18) Cintra, Camila Coppi; Baldin, Yuriko Yamamoto; https://lattes.cnpq.br/8785562528979416; https://lattes.cnpq.br/3824085172641551
This research aims to present and analyze the contributions of the Singapore's Mathematical Bars on the fraction teaching with a focus on problem-solving. This methodology was applied to a 7th-year middle school class in a public school of São Paulo State. The motivation for this study relies on the low rate of correctness observed in the São Paulo State's unified test regarding the fraction subject, as well as on the importance of this subject in an effective transition to algebra. The Singapore's Mathematical Bars methodology was adopted because it enables a pictorial visualization, building a bridge between concrete and abstract, being particularly suitable for approaching the part-whole relations and comparison matters. The proposed activities were based on the Singapore's book "My Pals Are Here!" and cover basic fraction concepts such as numerator and denominator, obtainment of equivalent fractions, and addition and subtraction fraction operators with both equal and distinct denominators. The analysis of the results obtained in the classroom is intended to serve as a complementary material for professors which face similar teaching problems.
O potencial dos grupos interativos para o ensino de proporcionalidade: um estudo de caso com alunos do 8º ano do Ensino Fundamental
(Universidade Federal de São Carlos, 2017-12-18) Ferreira, Márcio José; Pires, Rogério Fernando; https://lattes.cnpq.br/2795801064535157; https://lattes.cnpq.br/1747865569873097
This research has as its theme the teaching of proportionality with Interactive Groups from the perspective of Rodrigues and aims to understand the potential of Interactive Groups for the process of teaching and learning of proportionality in a group of 8th grade Elementary School. The research answered the question: “How does the teaching/learning process of the concept of proportionality involving Interactive Groups occur?”. The theoretical basis was based mainly on the presuppositions that are based on the principles of Dialogic Learning, formulated by Ramón Flecha. The qualitative research in the case study modality occurred in a municipal public school located in Cajamar, state of São Paulo, and the information was produced and collected in the second half of 2016. The data triangulation technique involved audiovisual records, written records of the students, notes of participant observation of the teacher-researcher and semi-structured interviews. In order to describe and analyze the students learning process, we rely on the ideas of Onuchic and the National Curriculum Parameters on problem solving and on studies that discuss teaching and learning of proportionality such as Ávila, Lima and Carraher. The results showed that the Interaction with Interactive Groups is configured as an organization that allows working in the perspective of problem solving. The use of the definition of quantities directly or inversely proportional to the nature of the relationship between magnitudes was emphasized as learning; understanding the concept of proportional magnitudes, solving problems. The importance of this research lies in the fact that the process of teaching/learning of proportionality involving Interactive Groups values the construction of knowledge by the active student, unlike traditional activities, an alternative to better learning for students.
Aplicações do Teacher Behavior Checklist à formação e avaliação de professores de nível superior: contribuições analítico-comportamentais e psicométricas
(Universidade Federal de São Carlos, 2017-12-18) Henklain, Marcelo Henrique Oliveira; Haydu, Verônica Bender; https://lattes.cnpq.br/1726041421275880; Carmo, João dos Santos; https://lattes.cnpq.br/1263046410329694; https://lattes.cnpq.br/3486276032268863
The training and evaluation of teaching for college teachers still needs to be deepened in relevant aspects, such as the instrumentalization of the teacher so that he is able to improve himself in his work. A feasible proposal to contribute to the improvement of teaching practice is to use the Teacher Behavior Checklist (TBC), adapted to be fulfilled by students, as an auxiliary tool to conduct teacher’s formative assessment. Research in several countries has shown that teachers and students consider TBC representative of what an effective teacher does to teach, and psychometric evidence supports its use for this teacher assessment modality. The general objective of this research was to investigate evidence of validity and reliability of the TBC for the Brazilian university culture and to identify possibilities of the contribution of this instrument for the teachers training. This work was organized into five studies. Study 1 described the TBC’s adaptation process and presented evidence favorable to the use of this adapted version. Study 2 presented evidence of the content validity of this TBC version by means of two studies with Brazilian professors and undergraduates. The objective of the first one was to evaluate the degree of relevance of the TBC items and it showed that all items were considered very relevant. The second study investigated which are the 10 most important qualities of the TBC. Results indicated possibilities of approximation among the selection standards presented by students and teachers from Brazil and other countries, suggesting the feasibility of thinking about teaching practices useful for different college student’s cultures. Study 3 aimed to investigate evidence of validity and reliability of the current version of TBC. Results provided support for a two-factor model of TBC, similar to those proposed by the authors of the instrument. This makes it possible to compare data collected in Brazil and in the USA. Evidence of reliability has been documented, for example, through the Test-Retest procedure. In Study 4 the objective was to investigate whether the evidence of validity and reliability could be verified with samples from different geographical regions of Brazil, as well as to evaluate whether the present version of the TBC would allow identifying teachers with different degrees of teaching repertoires. The results provided support for the understandings formulated in Study 3 and evidence has been documented that TBC allows distinguishing between different quality degrees of teaching repertoires. In Study 5 an interpretation of the TBC items as behavior classes was presented and a description of the functional parts of three items of the instrument was carried out. Information that was not highlighted in the instrument and that is necessary for the planning of teacher training have been identified. It became clear that TBC can be used as a source to derive teaching objectives for teacher training. Cumulative evidence suggest that TBC can be used in future studies to investigate teacher education and assessment, and can be tested in an applied context as an auxiliary tool for the formative assessment of college teachers.
Educação ambiental e transformação de espaços urbanos: novas formas de habitar, múltiplas formas de aprender
(Universidade Federal de São Carlos, 2017-12-18) Alberto, Regiane de Sá; Oliveira, Haydée Torres de; https://lattes.cnpq.br/5458113597909705; https://lattes.cnpq.br/1522488332723318
All over the world today, there are more people living in cities than in the countryside. The accelerated urbanization associated with the socioenvironmental impacts of the capitalist mode of production is presented as one of the main problems of modernity. However, we can highlight in this destabilizing scenario initiatives aimed at reconciling urban environment and nature and the articulation between people in search of better cities to live and live together. Discussing the current environmental crisis requires taking into account actions articulated in the spheres of politics, economics, knowledge production and education, seeking the linkage between the real nature of environmental issues, human activities and educational processes. Critical environmental education can be seen as a possible translator of the language of collectives who bring alternative projects for the construction of a less predatory urban society. The focus of this investigation refers to the educational dimension of social practices of public intervention, admittedly guided by another environmental praxis. This praxis is revealed in the daily work of all those who are included as promoters of this new inhabit in realities of communitarian spaces that are proposed to new ways of working in and with the urban space. The concern that motivated this research is: were these interventions of transformation of urban spaces an environmental education happening in practice? And how do these people educate themselves and others in this group in this reality? In view of these questions, it was intended to understand this environmental educator process of transformation-re-signification-reoccupation of the spaces, from a contextual cut in the communitarian urban gardens that are spread and promote the environmentalization of the São Paulo/SP metropolis. Corresponding to our theoretical-methodological horizon, for this qualitative research, we take the position of participant observation and insert ourselves as participants in the context to be investigated. This point of departure and arrival allowed us a better understanding of the phenomenon (s) that involves (s) the action of humans between themselves and humans in / towards the environment. We conclude that this study focused on the experiences of transformation of urban spaces, with a cut to the context of some initiatives in urban community agriculture in the city of São Paulo/SP, confirms the prerogative of which we learn everywhere and can enrich the field of research in environmental non-school education, which involves efforts not only to look at the institutional and political relationships of educating themselves, but also m qualify its practice from the space in which it takes place. This is an effort that we have achieved by highlighting educational processes in the social practices of transforming public spaces in cities.
Efeitos dos agrotóxicos Kraft® 36 EC (abamectina) e Score® 250 EC (difenoconazol), isolados e em misturas, sobre organismos zooplanctônicos
(Universidade Federal de São Carlos, 2017-12-18) Moreira, Raquel Aparecida; Daam, Michiel Adriaan; https://lattes.cnpq.br/5357327697116655; Rocha, Odete; https://lattes.cnpq.br/7577441794992601; https://lattes.cnpq.br/4388003923600701
Toxic effects of the pesticides Kraft® 36 EC (i.a. abamectina) and Score® 250 EC (i.a. difenoconazol), isolated and in mixtures were evaluated on zoplanktonic organisms. Daphnia magna was used as test-organism to evaluate pesticide effects using the biochemical biomarkers cholinesterase (ChE), catalase (CAT) and lipid peroxidation (LPO), besides energy-related parameters (total proteins and lipids) together and energy consumption (EC). Possible effects of agrochemicals on tropical aquatic ecosystems were simulated and evaluated by acute and chronic toxicity tests with surface runoff from soil experimentally contaminated with both agrochemicals. The native cladoceran Macrothrix flabelligera was used as test-organism. Potential risks related to exposure to isolated compounds and their combinations were evaluated through microcosm experiments. A review of literature was performed to analyze the use of rotifers species as test-organisms for pesticide toxicity evaluation in aquatic ecosystems with emphasis on tropical configurations. It was found that there is great potential for using rotifers as test-organisms for toxicity evaluations and risk assessment. An evidence of this potential was a higher sensitivity of native species exposed to fungicides if compared to D. magna. The isolated compounds did not have effects on cholinesterase (ChE) and catalase (CAT), but their mixture induced an increase on these biochemical. Lipid peroxidation (LPO) was induced for D. magna was exposed to the fungicide. Reproductive output was small but protein was not quantitatively affected, but the highest combination of both pesticides resulted increased lipid reserves. Consumed energy was highly affected and stimulated in all treatments for both, isolated compounds and mixtures. For M. flabelligera, tests with mixtures revealed a concentration dependent deviation (DL) by IA model, with antagonism in low and synergism in high mixture concentrations. The microcosms receiving runoff from experimental soil contaminated with individual pesticides did not cause toxicity to the test-organism, however their mixture caused immobility. The microcosm treated by spray drift with both pesticides showed the highest toxicity effects. Our results suggest potential risk of the selected pesticides in environmentally relevant concentrations, especially if occurring together.
Fadiga em peças de madeira para uso estrutural
(Universidade Federal de São Carlos, 2017-12-18) Carvalho, Johnny Soares de; Christoforo, André Luis; https://lattes.cnpq.br/7623383075429186; https://lattes.cnpq.br/6710887043385415
The purpose of present study was to create a theoretical model that allowed with security and reliability to obtain, values of strength and stiffness to which the structural element will be submitted throughout its useful life. The effect was studied for strength and stiffness properties, and the modulus of elasticity (EM) and bending strength (fM) were evaluated according to the increasing number of cycles of the fatigue test for the five classes of hardwoods, recommended by NBR 7190/1997. These results allowed to construct a fatigue curve, relating the two variables as a function of the number of cycles (Nc) - construction of the curves E x Ncicles and σ x Ncicles. The fatigue effect was present and pronounced in all resistance classes. A reduction in strength and stiffness properties was observed with increasing loading Nc applied at all frequencies. From the multivariate regression models and the respective determination coefficients, a generic model was obtained for the set involving the five wood species, emphasizing the insertion of the apparent density as an independent variable, which allowed a greater generalization of the use of the adjustments in the estimation of the EM and fM properties, presenting significant determination coefficients.
O Ministério da Educação (MEC) na Educação de Jovens e Adultos (EJA) : linguagem e discurso
(Universidade Federal de São Carlos, 2017-12-18) Teixeira, Odinei Inacio; Abreu, Ana Silvia Couto de; https://lattes.cnpq.br/7461517670259813; https://lattes.cnpq.br/0720999467723577
In this research, we aim to interpret the construction of meanings through the curricular guidelines published in the Curriculum Proposals, in the Notebooks about the EJA and in the Advertising Campaign of 2016, through these officials discourses and the interpretation of their representations on the EJA (Young People and Adults), because "the sense, for AD, is not already fixed a priori as the essence of the words, nor can it be any: there is a historical determination. Still one in-between. (ORLANDI, 2012, p. 27). Thus, the political discourse of the MEC (Ministry of Education) for the EJA constitutes subsidies for the development of educational projects that directly affect this public with the effectiveness or the non-effectiveness of these educational public policies and their respective social consequences. This research is based on the theoretical framework of Discourse Analysis postulated by Pêcheux (1988; 1990) and also on the theoretical aspects postulated by Orlandi (2007a; 2007b; 2007c; 2012). We understand that the ideology of government permeates the MEC and is manifested in the Curriculum Proposals for the EJA, in the Notebooks and in the Advertising Campaign, and according to this movement of meanings, the government ends up perpetuating its dominant ideology with the society, with the subjects and , consequently, in relation to public educational policies. In this way, we have the presence of memory in relation to discourse, that is, interdiscourse. Given the choice of our research object, we adopted the following way from a qualitative research perspective in order to select the statements and images to interpretation, analysis and discussion: a) Visits to the MEC website, specifically, SECADI - Secretariat for Continuing Education, Literacy, Diversity and Inclusion - for the selection of documents, especially curricular guidelines about the EJA; b) Selection of the Curriculum Proposals for the EJA and the notebooks Working with the EJA; c) Visits to MEC profiles on social networks, especially on YouTube and Facebook for the selection of the Advertising Campaign movie (2016) with a recent approach to the EJA; d) Selection and organization of Proposals and Notebooks statements, and of the images obtained through screenshots from the Advertising Campaign for the construction of the discursive sequences in accordance with the selected themes; e) Analysis and interpretation of the discursive sequences supported in our theoretical framework, in order to understand the concepts that belong to the discursive phenomena under study. Our analyzes have made possible to understand that the illusion that government discourse constitutes a stable and closed space for interpretation and its construction of meanings, closes the spaces destined to the profusion of meanings different from those established by the enunciator, and which prevent us from seeing the need of public policies that meet the needs of young and adults learners. In accordance with this position, there is the interdiction of meanings and the construction of the illusion that society, as well as the governmental discourse on the EJA, is also stable and homogeneous. However, the rupture with stability and openness to interpretation show the need for the frequent elaboration of educational public policies that, in fact, meet the needs of the subjects not schooled at the regular age, allowing them a greater autonomy that could potentially be due to schooling.
Caracterização funcional e bioquímica do fator de transcrição rlmA e da interação de PkcA e Hsp90 no fungo Aspergillus fumigatus
(Universidade Federal de São Carlos, 2017-12-18) Rocha, Marina Campos; Malavazi, Iran; https://lattes.cnpq.br/1569614985704317; https://lattes.cnpq.br/9004361100176439
Aspergillus fumigatus is an opportunistic human pathogen that causes systemic infections, including invasive pulmonary aspergillosis in immunocompromised individuals. Survival of this fungus is highly dependent on the cell wall organization and function of its structural components. Cell wall integrity pathway (CWIP) is the primary signaling cascade that controls de novo synthesis of the cell wall. In Sacharomyces cerevisiae, this event depends on the RLM1 transcription factor that contains the MADS-box domain. In this work, we investigated the function of RlmARLM1 in the CWIP of A. fumigatus. We show that the ΔrlmA strain presents an altered cell wall composition, besides defects related to vegetative growth and cell wall integrity in the presence of cell wall stressors agents. Genetic assays indicated that rlmA is positioned downstream of pkcA and mpkA genes in CWIP, and, as a consequence, the loss of rlmA function results in alteration of genes expression of the encoding cell wall related proteins. The transcription factor RlmA positively regulates the phosphorylation of MpkA, which is induced in both protein and transcriptional levels during cell wall stress. rlmA is also involved in tolerance to oxidative stress, whereas the main genes that regulate tolerance to reactive oxygen species had their expression reduced in the ΔrlmA mutant. In addition, ΔrlmA strain presents attenuated virulence in a murine model of invasive pulmonary aspergillosis and induced increased secretion of TNF-α. There was a higher rate of conidia phagocytosis of the mutant ΔrlmA in comparison to the wild type. The ΔrlmA mutant exhibits reduced asexual sporulation, and regulates transcription of the major transcription factors involved in conidiogenesis in Aspergillus ssp., i.e. brlA and abaA. RlmA is also important in the production of secondary metabolites, including gliotoxin and fumiquinazoline (Fq) C, and positively regulates the transcription of the genes cluster responsible for Fq biosynthesis. A biological characterization showed that activity of FqC increase the production of the inflammatory cytokines TNF-α, IL-6, and pore formation in the plasma membrane, suggesting that this is a defense mechanism against other microorganisms or soil predators. Additionally, the role of the second transcription factor (SebA) in the production of FqC in A. fumigatus was reported. We have shown that maintenance of cell wall integrity is associated with thermotolerance in A. fumigatus, and the Hsp90, one of the main chaperone involved in the heat shock response, physically interacts with PkcA, MpkA, and RlmA. Furthermore, partial or total loss of function of these genes results in altered expression of the principal genes related to heat shock response in A. fumigatus. Additionally, the proteins MpkA and Hsp90 had their structure partially characterized. Overall results suggest that RlmA works as a transcription factor associated with the A. fumigatus CWIP acting downstream of the PkcA-MpkA signaling and regulating the response to several stresses caused to the fungal cell which emphasizes the importance of this pathway in the virulence and pathogenicity of this fungus.
Compósitos de polipropileno com fibra e nanofibrilas celulósicas preparados com auxílio da pulverização por cisalhamento no estado sólido - S3P
(Universidade Federal de São Carlos, 2017-12-18) Oliveira, Gean Henrique Marcatto de; Canto, Leonardo Bresciani; https://lattes.cnpq.br/7287108960864123; Lucas, Alessandra de Almeida; https://lattes.cnpq.br/9754332336954137; https://lattes.cnpq.br/2892871093566684
In this study, polypropylene (PP) compounds were prepared using three types of cellulose fiber, pulp fiber (CF), cellulose nanofibrils (CNF) and lignocellulosic nanofibrils (LCNF) extracted from Eucalyptus grandis. The cellulosic fiber content of the compounds ranged from 10 to 30% by weight. Polypropylene grafted with maleic anhydride (PP-g-MAH) was also used as a compatibilizer. The solid state shear pulverization technique (S3P) was employed with the aim of improving the blending and dispersion of fibers in the matrix and a comparison with the compounds containing freeze dried nanofibrils (FD) was performed. X-ray diffraction (XRD) was used to measure the crystallinity index of cellulosic fibers, as well as scanning electron microscopy (SEM) was used for morphological characterization. With the aid of the modules processed by S3P, the PP / FC 70/30 sample presented results in the best mechanical tensile results, with a 100% increase in tensile strength and 75% in Young's modulus in relation to PP pure. Agglomerated was observed by scanning electron microscope with dimensions around 200 μm in the composites with nanofibrils (NFC and NFLC). Formulas with 30% by mass of cellulosic fibers- FD (FC, NFC and NFLC) were processed directly by solid state extrusion (MSE) for comparison with an S3P technique. The composite PP / FC 70/30 was released by S3P was released at 10% over time and the impact at the same time was 15% lower than the composite processed directly by extrusion in the molten state, while samples containing nanofibrils (NFC and NFLC) their independent traction and impact properties are not subjected to the S3P technique. The S3P technique is viable in the preparation of composites with the cellulosic fibers in the presence of water, keeping the mechanical and morphological properties similar to the composites prepared with lyophilized nanofibrils.
Aspectos da biologia e do controle químico de Spermacoce verticillata L.
(Universidade Federal de São Carlos, 2017-12-18) Fadin, Dauri Aparecido; Monquero, Patricia Andrea; https://lattes.cnpq.br/2766526793830455; https://lattes.cnpq.br/6178012276418283
Weed control is an essential practice in cropmanagement. However, the use of herbicides may not be effective in some situations, ranging from problems in application technology to the selection of tolerant individuals and resistant biotypes. In the State of Bahia, Brazil, in cotton producing areas, Spermacoce verticillata (buttonweed) is not being controlled during burndownapplications. The objective of this project was to determine herbicide control options at different stages of development of plants, to verify the morphological aspects of the leaf surface of this weed and to observe the absorption and translocation of glyphosate by the plant. In a first experiment, the control of the plants with different herbicides was tested in the phenological stages of 2-4 true leaves, 4-6 true leaves and in the emission of floral buds, characterizing the application in post-initial, post-normal and post respectively. The experiment consisted of 19 treatments arranged in a completely randomized design, where the visual control of plants (%) was evaluated at 7, 14, 21, 28, 35 and 42 days. At 42 days, the remaining plants were dried and dry weight was recorded. These data were analyzed by the F test, which when significant, had their means compared by the Tukey test at 5% significance. In a second experiment, the foliar absorption and glyphosate translocation were analyzed by the use of the C14 technique in different phenological stages of plant development. This evaluation was performed for different periods after application (4, 6, 8, 12 and 48 hours) in the different parts of the plant (leaves above and below the application, stems and roots). In these same periods, the plants were radiographed. In a third experiment, the anatomy and leaf morphology of the species were analyzed through optical and scanning electron microscopy analyzes at the different stages of development of the species. The following characteristics were evaluated: total leaf blade thickness, chlorenchyma thickness, parenchyma thickness, cuticle and epidermal thickness on abaxial and adaxial surfaces, central rib height and width. Several chemical control options for S. verticillatta have been found, ranging from contact herbicides such as paraquat to systemic, as 2,4-D and glyphosate and several product mixtures with glyphosate. The sensitivity of the plant was altered according to the stage of development and the herbicide applied. Plants with more advanced stages of development (flowering) showed slower absorption of glyphosate herbicide and intermediate plants absorbed smaller total amounts of the herbicide (4-6 leaves). Translocation was also facilitated in new or old plants, mainly influenced by translocation above the point of application. The translocation to the roots was larger and faster for plants in a lower vegetative stage of development. With the evolution of the stages of development of S. verticillata the plants began to show reductions of their leaf thickness due to reductions of the abaxial epidermis, the measurements of the conducting vessels and their parenchyma. In more advanced stages (from 6 leaves) of development the leaves presented in their adaxial surface a smaller quantity of stomata and a greater quantity of trichomes. No links were found between these characteristics and the species differential susceptibility to glyphosate applications. However, plants of S. verticillata presented several morphoanatomical changes that can alter the absorption and translocation of herbicides in the different phenological stages.