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Biopolímeros ferti-liberadores: uma proposta de recipiente no cultivo de mudas de antúrio
(Universidade Federal de São Carlos, 2023-07-21) Petruz, Alessandra; Faez, Roselena; Souza, Claudinei Fonseca; https://lattes.cnpq.br/4858219292242433; https://orcid.org/0000-0001-9501-0794; https://lattes.cnpq.br/7532808144934167
The inadequate handling of plastic waste used in agriculture, associated with the high need for soil fertilization, has caused several negative impacts on the environment. Developing improved efficiency fertilizers (EEF) based on biodegradable materials has become a promising alternative for fertilizer intensification since EEFs ration the amount of available fertilizer, reducing losses. Such sustainable agricultural practices have contributed to achieving the Sustainable Development Goals (SDGs). The objective of this work was, in the first stage, to produce films based on carrageenan (KC) and alginate (ALG) and to evaluate the influence of nanofibrillated cellulose (CNF) in concentrations of 0, 2, 3, 4, and 5 % (m/m ) and monoammonium phosphate (MAP) at a concentration of 20 % (m/m) on the thermal, structural, morphological and mechanical properties of films cast on aluminum substrates coated with Teflon, polypropylene (PP) and acrylonitrile-butadiene-styrene (ABS). We also evaluated the biodegradation, swelling, and release of PO43- ions in the water. In the second stage, to produce a material with 4 % (m/m) of CNF and a multi-nutrient formulation (calcium nitrate, potassium nitrate, MAP (monoammonium phosphate), MKP (monopotassium phosphate), potassium sulfate, magnesium sulfate, and ConMicros) to achieve 0.4 dS m-1; 0.8 dS m-1; 1.2 dS m-1 and 1.6 dS m-1 according to the nutritional recommendation for the anthurium culture and to evaluate its thermal, structural, morphological, biodegradation and field performance properties. Higher concentrations of CNF altered the morphology of the composites and aided in fertilizer dispersion, delaying the release rate. The addition of fertilizer influenced the biodegradation process by increasing the microbiota and tensile strength. According to the biometric analyses, the highest concentration of fertilizers corresponding to 1.6 dS m-1 contributed to the better development of anthuriums. In conclusion, CNF and fertilizer contribute to more resistant films, with a lower PO43- ion release rate and biodegradable potential, making them a potential for cultivation containers used in anthurium (Anthurium andraeanum) culture.
Estudos sobre a construção e uso de materiais manipuláveis no ensino de ciências naturais para estudantes com surdocegueira
(Universidade Federal de São Carlos, 2023-07-21) Perassolo, Valquiria; Costa, Maria da Piedade Resende da; https://lattes.cnpq.br/2791098416503955; https://orcid.org/0000-0002-7420-5602; https://lattes.cnpq.br/7152098940158098; https://orcid.org/0000-0003-2611-0614
The school inclusion of people who are the target audience of Special Education is still one of the great challenges of Brazilian education. The large number of people excluded from the right of access to schooling is real and the issue is even more complex when it comes to people with disabilities, such as those with deafblindness. This research focuses on the education of children, adolescents and young people with deafblindness, who are socially invisible and who often have their right of access and permanence in education denied due to failures of the educational system to receive and include them. The main objective is to highlight and analyze the potentialities and challenges found on the use of manipulable materials in teaching of Natural Sciences for students with deafblindness. As methodology, the qualitative approach was the option of the kind of case research. Two deafblind students from the Center for Care and Support to the Deafblind (CEAADA) participated in the research, their guardians who participated in the interview to characterize them, two teachers who attended them in the year 2021, and two teachers who attended them in the year 2022. Propositions of manipulable materials used by teachers in teaching natural sciences to students with deafblindness were observed and materials were also made and supplied according to the students' needs. All these materials were handcrafted, that is, not industrialized. The analyzes were guided by the effort to understand the demands of schooling deafblind students and the potentialities and challenges as to the use of manipulable materials adopted for teaching such students. As a result, the data indicate that families consider the schooling process important, but show many difficulties in passing on the activities proposed by the teachers during remote teaching. The teachers participating in the research, although they have little experience in teaching students with deafblindness, they tried to research and adapted the activities that would be proposed. The participating teachers and the researcher established a partner relationship, in which they discussed and developed together the preparation of materials and activities proposed during the research period. The teachers proved that they have knowledge of what manipulable materials are and these materials show great potential in the teaching of these students, as they allow them to explore different textures, formats and sensations. It is also evident that the teachers notice the need for a differentiated pedagogy for teaching people with this disability.
Avaliação de aditivos poliméricos e cerâmicos para a otimização microestrutural de refratários semi-isolantes
(Universidade Federal de São Carlos, 2023-07-21) Farias, Thiago Wisley Barbosa de; Luz, Ana Paula da; https://lattes.cnpq.br/3470395641242374; https://orcid.org/0000-0002-5941-5388; https://lattes.cnpq.br/3160573002957297; https://orcid.org/0000-0002-9249-6327
Macroporous insulating refractories have been extensively investigated due to their low thermal conductivity, low density, and non-toxicity compared to fibrous ceramic insulators. However, there are still challenges in adjusting the processing parameters of these materials to obtain microstructures with optimized characteristics. In this context, the present project aimed to evaluate the feasibility of using expanded polymeric microspheres or hollow ceramic microspheres in semi-insulating refractory compositions, with the goal of identifying the most suitable conditions for achieving materials with apparent density of up to 1.7 g/cm3 and thermal conductivity lower than 1 W/m·K in the temperature range between 30 and 800°C. Additionally, to optimize the mechanical strength of the prepared semi-insulating materials, compositions containing calcium aluminate cements or geopolymers as binders were prepared and compared. Formulations based on fused silica were processed and characterized for their rheological, physical, mechanical, and thermal properties. The results indicated that the selected microspheres acted effectively as pore-forming agents, with the polymeric additives promoting the formation of closed pores in the resulting microstructure. In particular, the ceramic containing 0.6 wt.% of polymeric microspheres and a calcium aluminate cement richer in alumina (Secar 71) exhibited the best performance among the studied systems. This castable achieved a flexural strength of 9.21 MPa (after drying at 110°C) and 4.29 MPa (after firing at 815°C), an apparent density of 1.62 g/cm3, and a thermal conductivity of 0.668 W/m·K at 800°C. The semi-insulating materials prepared with geopolymers also demonstrated promising properties, as even in the absence of pore-forming agents, it was obtained refractories with superior flexural strength (surpassing the compositions with cement), an apparent density of 1.68 g/cm3, and a thermal conductivity of 0.735 W/m·K at 800°C.
Aplicação web back-end de um fantasy game
(Universidade Federal de São Carlos, 2023-07-21) Rodrigues, Kaio de Melo; França, Celso Aparecido de; https://lattes.cnpq.br/4547836128892982; https://orcid.org/0000-0003-2235-9551; https://lattes.cnpq.br/5730881171653658
In Brazil, the most popular sport is football and, therefore, it is recognized in scenarios that go beyond the lawns, such as the Fantasy Games. Users of this game style create and manage their own teams online, using real players from football teams around the world. Each player is assigned a point value based on their skill and performance history. Today there are different fantasy football games, but the most relevant in the country is Cartola FC. In this work, a Back-End web application of a Fantasy Football Game similar to Cartola from Rede Globo, called InterRep Manager, was developed. In it, users manage the scores of real players who participated in InterReps, a football tournament between the republics of São Carlos that took place in the year 2022. The tournament scores were used in the application. To evaluate the functionality of the application, the performance of three users and 15 players in three matches was simulated. So far, the software has proved to be functional, from the login stage to the calculation of the score.
Aspectos que conferem complexidade a interpretação na perspectiva do intérprete educacional do ensino médio
(Universidade Federal de São Carlos, 2023-07-21) Oliveira, Patricia Cardoso de; Lacerda, Cristina Broglia Feitosa de; https://lattes.cnpq.br/9468232016416725; https://orcid.org/0000-0002-3250-1374; https://lattes.cnpq.br/8560935678654879; https://orcid.org/0000-0002-0831-9767
At the expense of a greater insertion of the deaf in the academic environment, the educational intérpreter of Brazilian Sign Language - Libras, has been gaining recognition in relation to the importance of its performance and its influence in the teaching and learning process of students with deafness. That said, the present study explored the aspects that add complexity to the interpretation of Portuguese into Libras in the educational environment, aiming to identify, understand and offer reflections on the elements that foster this phenomenon, with the aim of building new perspectives in the field of action of the educational intérpreter Libras, with emphasis on collaborative work between the teacher and the educational intérpreter. For this, a single case study was carried out, using the simple self-confrontation instrument, proposed by Yves Clot (2010), in work psychology (Clinic da Atividade) and based on the principles of Bakhtin's dialectic (2006), together with the conception of “Saying the 'same' to others: essays on translation” by Adail Sobral (2008), as well as the theorization about the work in partnership between the teacher and the educational intérpreter. For the analyses, two categories were highlighted: i) constructions of new concepts or complex concepts in the source discourse; and ii) interpretive lapses. Such categories provided the survey of elements that confer complexity to the interpretative act in the educational sphere, which were organized in the following axes: I) Construction of concepts: from simple to complex; II) the collaborative work between the teacher and the educational intérpreter; III) emotional aspects in the performance of the educational intérpreter. The highlighted elements, which according to the perspective of the high school educational intérpreter, exert great influence in making the task of interpreting from Portuguese into Libras usually complex, if better known they can be tackled in the perspective of making the work of the educational intérpreter of Libras less arduous.
Design de aços inoxidáveis austeníticos de alto teor de nitrogênio via triagem de alto desempenho por método CALPHAD
(Universidade Federal de São Carlos, 2023-07-21) Ferreira, Victor Hugo Mafra Monfredo; Coury, Francisco Gil; https://lattes.cnpq.br/8609825406277730; https://orcid.org/0000-0002-0457-2087; Koga, Guilherme Yuuki; https://lattes.cnpq.br/0933095081175012; https://orcid.org/0000-0003-0792-1139; https://lattes.cnpq.br/6523666198326490; https://orcid.org/0000-0002-7782-1267
Nickel is essential for austenitic stainless steels of the 3xx class (8-10 wt%) due to its austenitizing character. However, its notorious price volatility directly affects the stainless steel industry. In light of this, there is a need to develop stainless steels that partially replace nickel with other austenitizing elements. The aim of this work was to develop compositions of austenitic stainless steels with a high N content using computational methods. Computational tools based on the CALPHAD method were employed to select a composition based on predefined criteria (composition, phases present, % N, cost, and PREN). The alloy's microstructure was analyzed through optical and scanning electron microscopy, while the phases present were identified through X-ray diffraction. The chemical composition was determined using spark emission spectroscopy; elements C, S, N, and O were analyzed by combustion and quantified by infrared absorption. Mechanical properties were evaluated according to ASTM E8/E8M-11 standards. Pitting corrosion resistance was assessed through cyclic potentiodynamic polarization in 3.5 wt% NaCl, and sensitization was evaluated following ISO 12732; susceptibility to intergranular corrosion was determined according to ASTM A262-15 Practice A. Electrochemical impedance spectroscopy tests were also conducted as a complement. After high-performance screening, manual modifications were made to the compositions to improve nitrogen solubility. The results demonstrated that the developed alloys exhibited an austenitic microstructure with the presence of AlN, reducing the nitrogen content in solid solution. The mechanical properties of the alloy surpassed those of AISI 201 steel. However, due to the presence of AlN, the corrosion resistance behavior of the alloy was affected. These findings are significant for the development of austenitic stainless steels with a high nitrogen content, aiming to enhance their mechanical properties and corrosion resistance.
Identificação de atividades cotidianas com membros superiores através de sensores inerciais
(Universidade Federal de São Carlos, 2023-07-21) Girardi, Paulo Matheus; Nogueira, Samuel Lourenço; https://lattes.cnpq.br/2287847504423307; https://orcid.org/0000-0002-3342-7436; https://lattes.cnpq.br/8258774819324497; https://orcid.org/0000-0002-7090-9813
In this work, the development of data processing strategies and methodologies for identifying 7 everyday activities performed with the upper limbs was proposed, with the support of inertial sensors and machine learning techniques. Computational methods were used for data processing, including data synthesis to homogenize the number of samples, digital filter bank, Hamming windowing, feature extraction, and classification using a neural network with the Matlab Neural Net Pattern Recognition toolbox. In this study, two units of inertial measurement were used, one on each wrist. This choice was made because a significant portion of the performed activities requires cooperation between the two limbs. Thus, through supervised training of the neural networks, an average accuracy of over 90% was achieved for activity identification, demonstrating the feasibility of the proposed strategies for identifying daily activities involving the upper limbs.
Atividades de pronúncia no ensino de inglês como língua estrangeira: reflexões com professores em contexto de aulas individuais
(Universidade Federal de São Carlos, 2023-07-21) Sarturato, Gabriel Maldonado Fabbro; Paula, Sandra Regina Buttros Gattolin de; https://lattes.cnpq.br/9228036521343293; https://lattes.cnpq.br/0797881241667691
In Applied Linguistics there is increasing attention to foreign language pronunciation, and many pedagogic ideas explore beyond the classic practice of ‘listen and repeat’, which is still very common in many language teaching contexts. Many aspects of pronunciation need to be treated in class, and repetition only is not sufficient to address them all. Research has shown that description of the phonological structures, listening discrimination activities, and other forms of oral production that do not focus only on repetition show efficacy in pronunciation development, speaking, and listening. Repetition activities also can be reshaped to reach better contextualization and student engagement. The advancements in research, however, find little insertion in many language learning courses and teacher education. This research aimed to analyze how some teachers of English as a foreign language understand pronunciation instruction and its function in class. The context studied was one-to-one teaching. Three teachers and their respective students participated. They were exposed to pronunciation activity proposals, and selected the ones they found could be most helpful for their students, edited them, and implemented them in classes. Firstly, the teachers were interviewed about their perspectives on pronunciation and pronunciation teaching. Then, ideas for activities were sent by the researcher. The teachers then recorded the activities chosen. The researcher made an effort not to impose his views on the teachers, but to help them according to their own approaches. The students briefly presented their impressions of the activities. Later, recall sessions were recorded with each teacher for them to observe and reflect on the class. A last contact (via text message) was made with the teachers to ask questions that were raised during the analysis of the recall sessions. The results revealed that the teachers were keen to complement their common pronunciation instruction practices with the activities chosen. It was possible to recognize a clear influence of their teacher education backgrounds in their approaches. The three teachers demonstrated different views on the function of pronunciation and how to teach it. The students showed openness to the activities presented to them and pointed out that they would like to practice more with these activities.
Biestabilidade óptica em átomos de três níveis em uma cavidade óptica
(Universidade Federal de São Carlos, 2023-07-21) Proença, Lucas Araujo; Souza, James Alves; https://lattes.cnpq.br/2212240621620011; https://lattes.cnpq.br/2808532350048558
The phenomenon of optical bistability in atomic systems confined in an optical cavity has been extensively explored due to its potential for applications such as optical switches, memories and optical transistors. The bistability observed in multi-level atomic systems has some advantages over the usual two-level system with respect to non-linear optical properties, absorption and scattering. The configuration of atoms with more than two levels allows the use of other electromagnetic fields by coupling different atomic transitions resonantly, or quasi-resonantly, making it more feasible to manipulate and control non-linear optical processes, which may be related to the phenomena of electromagnetically induced transparency (EIT - \textit{Electromagnetically Induced Transparency}) and coherent population trapping (CPT - \textit{Coherent Population Trapping}). In this work we theoretically study the CPT phenomenon in cavities to explore the control and properties of optical bistability in systems composed of $N$ three-level atoms in $\Lambda$ configuration, independently coupled to the same field mode of an optical cavity. To obtain the interaction hamiltonian of the system we used the semiclassical approximation, which consists of considering atoms quantumly and the cavity field classically. Through the formalism of the master equation, we derive the Maxwell-Bloch equations and the dynamics of the system was obtained through computational simulations performed in MATLAB. The obtained results show that it is possible to obtain a sensitive control of the optical bistability from the adjustment of parameters external to the system, such as the frequency and intensity of the test field and the intensity of the control field. The possibility of controlling light with observed light in the studied system, through the phenomenon of optical bistability, can be promising for the development of optical devices with different functionalities.