Browsing by Issue Date, starting with "2023-07-11"

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    Relatividade geral, buracos negros e ondas gravitacionais
    (Universidade Federal de São Carlos, 2023-07-11)
    Malafatti, Vinícius dos Santos
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    Santarelli, Raphael
    ;
    https://lattes.cnpq.br/3591899759824320
    ;
    https://lattes.cnpq.br/0107098543825862
    In this study, firstly, the basic ideas, concepts and principles of Special Relativity are introduced, to help understand the construction of General Relativity. The second chapter is an introduction to the mathematical formalism of General Relativity, such as the covariant derivative, Riemann tensor and parallel transport. In the next chapter the construction of Einstein's equation using a classical approach is shown. The last two chapters present the first two solutions of Einstein's equation, the first is the Schwarzschild solution, which contains the precession of Mercury's perihelion and the surprising result: the existence of black holes. The last one is a solution given by Einstein, which consists of linearizing his equation using a small disturbance in the metric. This solution shows the existence of gravitational waves in the space-time, how they are produced, how they propagate and how to detect them.
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    Material particulado atmosférico sedimentável que afeta o desempenho de natação e a taxa metabólica aeróbica da tilápia do Nilo (Oreochromis niloticus)
    (Universidade Federal de São Carlos, 2023-07-11)
    De Angelis, Carolina Fernandes
    ;
    Fernandes, Marisa Narciso
    ;
    Leite, Cléo Alcantara Costa
    ;
    https://lattes.cnpq.br/2946803734091200
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    https://lattes.cnpq.br/3021357484136942
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    Comportamento magnético de compósito multiferróico heteroestruturado bifásico de CFO e PZT preparado eletroquimicamente
    (Universidade Federal de São Carlos, 2023-07-12)
    Costa Júnior, Lázaro José Dalla
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    Gualdi, Alexandre José
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    Pereira, Ernesto Chaves
    ;
    https://lattes.cnpq.br/5751113105751035
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    https://lattes.cnpq.br/1505400360366643
    This work proposed a new synthesis route for biphasic and lamellar composite ceramics of CoFe2O4 (cobalt ferrite) and Pb(Zr0,53;Ti0,47)O3 (lead zirconate titanate). The synthesis of CoFe2O4 films was performed using the electrochemical techniques electrodeposition, anodization and electrophoresis. Two synthesis conditions were tested, differing in applied potentials. The first condition applying 1060 mV resulted in a higher ferrite grain density compared to the second applying 1160 mV. The Pb(Zr0,53;Ti0,47)O3 phase was also solo synthesized. Structural analyzes revealed the formation of ferrimagnetic and ferroelectric phases through X-ray diffraction. Scanning electron microscopy showed that, before the synthesis of the ferroelectric phase, cobalt ferrite had needle-shaped grains with dimensions in the micrometer scale, which resulted in a magnetic behavior like that of spin glass in relation to temperature. The magnetic characterization as a function of the magnetic field applied at different temperatures. For sample the synthesized sample being the 1060 mV present a higher coercivity than that synthesized at 1160 mV. After Pb(Zr 0,53;Ti0,47)O3 synthesis, SEM images show that in both samples the PZT film showed high porosity. Although the magnetoelectric signal was not observed, the samples exhibited a small remanent polarization and a significant change was verified in the Ms and magnetic anisotropy of the films, before and after the polarization of the samples, but not in their coercivity. Thus, it was concluded that the proposed electrochemical route allowed the synthesis of multiferroic films.
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    O uso de algoritmos de classificação para determinar estoques de segurança
    (Universidade Federal de São Carlos, 2023-07-13)
    Sanches, Felipe Norato
    ;
    França, Celso Aparecido de
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    https://lattes.cnpq.br/4547836128892982
    ;
    https://orcid.org/0000-0003-2235-9551
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    https://lattes.cnpq.br/1413814764753839
    This work analyzes the application of different Artificial Neural Network algorithms with the objective of classifying candidate products for safety stock parameterization based on the purchase history of these products. The study brings discussions about the importance of the quality of the treated data and the importance of analyzing the problem, the objectives and the balance between the level of customer service, that is, the expected execution time, and the cost of inventory. K-means, affinity propagation, mean displacement and hierarchical clustering algorithms, which include the Ward and complete linkage methods, were studied. Through the application of these algorithms, it was possible to generate distribution graphs of classified points and calculate the correlation of the groups found by the different algorithms. For the presented problem, an optimal number of groups value was determined for a better classification of the products. The algorithms that showed the highest correlation were the K-means and Ward algorithms, which provided an efficient classification of data into 3 groups.
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    Anotação semântica baseada em ontologia aplicada em imagens médicas
    (Universidade Federal de São Carlos, 2023-07-13)
    Pereira, Juliana Wolf
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    Ribeiro, Marcela Xavier
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    https://lattes.cnpq.br/0300141044144026
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    https://orcid.org/0000-0002-2323-5326
    ;
    https://lattes.cnpq.br/1512389839368718
    Breast cancer is one of the most common types of cancer among women in Brazil and worldwide. Early diagnosis of a breast lesion is a priority for effective treatment at lower costs, with mammography being the most used exam. In this doctoral research, was developed the MUSA method to classify and semantically annotate mammography images based on the fusion of multimodal information, providing a fuller image annotation than the current state of the art. For this, the approach includes a text mining process, an image mining process, and an ontology engineering process. With the text mining process, it is possible to establish the contextual features based on similarity and co-occurrence relations between pairs of words in the same medical report. The image mining process allows classifying a mammography image using an end-to-end deep learning strategy. In the ontology engineering process, we built the AnotaMammo ontology, composed of the annotation ontology and the Mammo domain ontology. AnotaMammo allows the semantic annotation of mammography images. The text mining results were used to generate semantic rules, included in AnotaMammo. The results of the image mining process surpassed or compared with studies published in the literature, reaching more than 92% accuracy for classifying lesions as mass or calcification. The results also demonstrate that the AnotaMammo ontology adequately performed the semantic enrichment of the classification, in addition to having adequately performed the fusion of multimodal information. Finally, the MUSA method adds information to make the result more semantic and interpretable, thus reducing the semantic gap.
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    O sujeito neoliberal mirim: a semântica da obediência retratada em vídeos de YouTube
    (Universidade Federal de São Carlos, 2023-07-13)
    Calonego, Mariana
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    Gatti, Márcio Antonio
    ;
    https://lattes.cnpq.br/0369563657842763
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    https://orcid.org/0000-0001-9902-2856
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    https://lattes.cnpq.br/1241344833528211
    Considering childhood as a product of culture, his understanding requires the comprehension of social organization modes. Under the globalized logic of capitalism, subjectivities embody the neoliberal logic of performance and competitiveness. Adding technological dominance in people's daily lives, ways of working, relationships and desire undergo important transformations in contemporary times. In face of this, childhood suffers the consequences. Being assigned to children’s the role of corresponding to an overqualified place, they are expected to become, ever earlier, ready for future participation in a competitive labor market. “Already being” becomes the imperative of this moment. Access to digitality, fosters this logic and allows for a type of social participation that goes in the direction of “already being” a professional: young youtuber. In this research, we used the YouTube video platform to investigate the role of children nowadays. Based on Discourse Analysis, we analyzed videos starring children’s and identified aspects that put them in similar conditions to those of the neoliberal subject. The results of the data analysis, indicate a professionalization of the channels that, together with the present narratives in the videos, enunciate a neoliberal discourse. In addition, the dedication of the channels to a supposed transmission of conduct parameters to children, engenders the idea of a semantics of obedience, which seems to translate what is socially expected from children.
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    Partial automation of the seismic to well tie with the matching region estimation and segmented global optimization
    (Universidade Federal de São Carlos, 2023-07-13)
    Silva, Rafael da Costa
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    Silva, Diego Furtado
    ;
    https://lattes.cnpq.br/7662777934692986
    ;
    https://orcid.org/0000-0002-5184-9413
    ;
    https://lattes.cnpq.br/9614463991077343
    Geophysical interpretation plays a fundamental role in the oil and gas exploration domain. Various geophysical methods can be employed to extract information about the geological configuration of rocks. The well-to-seismic tie, which involves matching well log profiles with observed seismograms, is a crucial activity in the processing and interpreting of seismic amplitudes. During the exploration phase, the seismic tie process helps the interpreter to understand the well region's seismic wavelet and the time-depth relationship. However, data noise and inherent uncertainties make the seismic tie time-consuming. This way, we propose a significant automation of the seismic tie process that estimates the probable alignment region and automatically aligns the seismic traces through segmented global optimization. The alignment region is estimated based on the velocity profile and alignment using the Dynamic Time Warping (DTW) algorithm. The three proposed methods accurately estimated the well base position in the seismic trace for most of the tested wells. Our approach performs the segmentation of the tying process by utilizing the time-depth relationship obtained from the initial alignment of synthetic and seismic traces using Constrained DTW. The segmentation of the Differential Evolution (DE) tying process increased the final correlation in all tested wells, with four achieving a correlation higher than 70% without causing unrealistic velocity variations.
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    Jogando em casa na pandemia: um estudo brasileiro de crianças de 1 a 10 anos no isolamento social pelo COVID -19
    (Universidade Federal de São Carlos, 2023-07-13)
    Pereira, Natássia Novaes
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    Sommerhalder, Aline
    ;
    https://lattes.cnpq.br/4775432120371947
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    https://lattes.cnpq.br/8552051554358905
    Nel 2020 molti Paesi sono stati improvvisamente sorpresi dal contagio accelerato e incontrollato del virus SARS-COV-2 (COVID-19). Nel marzo dello stesso anno, l'Organizzazione Mondiale della Sanità classificò il contagio come pandemia, dando il via a misure urgenti per controllare il contagio. In questo modo, il mondo intero ha iniziato ad adottare misure per affrontare la pandemia in modo da superarla. La presente ricerca si concentra sulla conoscenza e sull'esame del gioco dei bambini nell'isolamento sociale nelle case domestiche, a causa della pandemia. Il presente rapporto di ricerca è stato strutturato in quattro sezioni: sul gioco; sul bambino come soggetto di diritto e sull'infanzia virtuale; sull'educazione scolastica, in particolare la fase della scuola dell'infanzia e dei primi anni della scuola primaria, prendendo come base teorica la letteratura nel campo del gioco infantile e dell'educazione scolastica. Intreccia riflessioni sull'educazione a distanza e la vita quotidiana; sulla famiglia contemporanea e le sue caratteristiche relazionali e considerazioni sul rapporto tra famiglia e scuola, oltre che sulla famiglia nel contesto di una pandemia o di malattie con un'ampia gamma di contaminazioni. Questa ricerca deriva da uno studio più ampio e ha cercato di rispondere: durante il periodo di isolamento sociale, con cosa giocavano (giocano) i bambini brasiliani nelle loro residenze (case)? L'obiettivo è stato quello di identificare e descrivere, attraverso un esame del COVID-19, i giochi che si verificano nella vita quotidiana domestica dei bambini brasiliani durante l'isolamento sociale. Si tratta di uno studio quali-quantitativo che ha utilizzato un questionario online (e-survey) come strumento di raccolta, ottenendo 541 risposte da adulti, familiari di bambini. I risultati ottenuti sono stati organizzati nella prospettiva qualitativa, attraverso la domanda aperta (domanda 12) e ordinati per mezzo di assi e nell'aspetto quantitativo, i risultati sono stati organizzati attraverso un formato "grafico a torta". Lo studio ha verificato una maggiore partecipazione degli intervistati dello stato di San Paolo, che vivono in casa e fuori dai condomini chiusi. Ha anche verificato una maggiore partecipazione delle madri nelle risposte a questo sondaggio rispetto ai padri. Lo studio ha anche accertato che i bambini non hanno smesso di giocare e hanno fatto ricorso a innumerevoli attività, dentro e fuori casa, con ciò che era loro possibile. Infine, lo studio mostra un aumento, tra i partecipanti, del consumo di schermi da parte dei bambini durante la pandemia.
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    O pensamento algébrico e sua propositura no material EMAI do estado de São Paulo para o ciclo de alfabetização (1º ao 3º ano)
    (Universidade Federal de São Carlos, 2023-07-14)
    Marcondes, Rianne Schutzer Luiz
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    Ciríaco, Klinger Teodoro
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    https://lattes.cnpq.br/2947929641568853
    ;
    https://orcid.org/0000-0003-1694-851X
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    https://lattes.cnpq.br/4350496320857842
    This dissertation highlight the results found throughout the development of the master's research, linked to the Professional Graduate Program in Education, at the Federal University of São Carlos (PPGPE/UFSCar). As an objective, we sought to analyze the declared conception about the perspective of work with algebraic thinking present in the material "Mathematics Education in the initial years" (EMAI) adopted by the State Education Network of São Paulo (SP), as well as the nature of the tasks that involve him in the literacy cycle (1st to 3rd year). For this, we started with an initial mapping of Professional Graduate Programs in the state of São Paulo and events in Mathematics Education (ENEM and EPEM) for the analysis of existing productions on the subject, thus fulfilling the stage of "Literature review". In addition, we constitute the "Theoretical Reference" in the field of studies on curriculum, curriculum in Mathematics Education and algebraic thinking. This research presents a methodological approach of a qualitative nature, with a descriptive-analytical-interpretative character. The central instrument for data production adopted was the documental analysis of the EMAI material, mainly the nature of the mathematical tasks that involved algebraic thinking. The results obtained showed that the EMAI material, with regard to the literacy cycle, presents approximately 59 tasks that involve objects of knowledge and skills of the thematic unit Algebra, as proposed by the National Common Curricular Base (BNCC) and Currículo Paulista, however, if the teacher cannot understand what is being asked, he will not explore them in their potential and will not develop algebraic thinking with the students. This fact demonstrates the need to invest in continuing education for these professionals, since it is challenging to work on aspects of algebraic thinking in the early years, as they did not have contact with this theme in their initial training. As a result of this research, an Educational Product was created in digital book mode (e-book) entitled "Children's Literature and Mathematics: proposals for tasks involving algebraic thinking for the literacy cycle", which presents possibilities of mathematical problematization with the unit Algebra theme in the first years of schooling.
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    Dimensión colectiva de las acciones profesionales en terapia ocupacional: percepciones situadas a partir de experiencias en Argentina, Chile y Colombia
    (Universidade Federal de São Carlos, 2023-07-14)
    Firsenko, Ekaterina
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    Malfitano, Ana Paula Serrata
    ;
    https://lattes.cnpq.br/1462870858750395
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    https://orcid.org/0000-0002-0502-3194
    ;
    https://lattes.cnpq.br/7108114780826054
    La cuestión social es constituida por las acciones de explotación propias del capitalismo, que agranda la brecha entre las clases, disminuye la cohesión social, modifica los mecanismos de la solidaridad y profundiza el individualismo. Así, surge que el debilitamiento de las protecciones y los soportes sociales presentan una relación directa con el sistema actual, como también con la pobreza, la exclusión social y la estigmatización. Justificación: A partir del desenvolvimiento del contexto actual caracterizado por el liberalismo, emerge la necesidad de que la profesión conforme nuevas lecturas sobre la realidad para el enfrentamiento de las problemáticas que derivan de la cuestión social. En este sentido, las explicaciones individuales de las problemáticas sociales son insuficientes para dialogar sobre la dimensión social. Al integrar la cuestión social a la profesión de terapia ocupacional, surge la importancia de analizar la dimensión colectiva de sus acciones profesionales, con el fin de desenvolver una acción que efectivamente aborde las contradicciones del nivel macroestructural. Objetivo: Conocer la dimensión colectiva de las acciones profesionales en terapia ocupacional a través de la percepción de lxs profesionales de Argentina, Chile y Colombia. Métodos: Fue seleccionada una visión materialista-histórica fundada en la terapia ocupacional social, para conocer las acciones de lxs terapeutas ocupacionales en una dimensión colectiva. Fueron contactadxs colegas a través de informantes claves y se realizaron 27 entrevistas semi estructuradas de modo virtual. Los datos se sometieron al análisis de contenido temático. Resultados: Fueron seleccionados los siguientes ejes de análisis: visión de la terapia ocupacional; teoría que respalda las prácticas colectivas; metodología de las prácticas colectivas; dimensión colectiva de las acciones profesionales en terapia ocupacional; dimensión macrosocial y colectivismo en terapia ocupacional, dialéctica individual-colectivo, ejemplos de experiencias colectivas no acertadas y prácticas colectivas con el sujeto individual y sobre cómo conformar acciones colectivas. Conclusión: La dimensión colectiva de las acciones en terapia ocupacional se caracteriza por una visión contraria al principio liberal del individuo, en una actuación que tiene el objetivo de desarrollar una visión social del Estado, de la sociedad y de la política, lo que dialoga directamente con las propuestas de la terapia ocupacional social. Así, la discusión sobre el colectivismo en terapia ocupacional puede estar presente desde las acciones con los sujetos individuales, en la clínica, hasta en el trabajo comunitario, ya que articula dialécticamente sujetos individuales y colectivos. El diálogo latinoamericano posibilita contribuir con la discusión acerca de los fundamentos de la terapia ocupacional y puede colaborar con el abordaje de la cuestión social a través de las referencias que parten de los principios de la acción colectiva. Palabras clave: Colectivismo. Terapia ocupacional social. Cuestión social.
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    O corpo no espaço, o espaço do corpo: considerações sobre a filosofia de Merleau-Ponty
    (Universidade Federal de São Carlos, 2023-07-14)
    Marques, Rafaela Ferreira
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    Moutinho, Luiz Damon Santos
    ;
    lattes.cnpq.br/9475267722538751
    ;
    https://orcid.org/0000-0002-6343-571X
    ;
    lattes.cnpq.br/3913396040221427
    Cette thèse suit Maurice Merleau-Ponty dans sa recherche d’un fondement spatial et concret pour sa phénoménologie. Pour cela, nous commençons notre parcours en réfléchissant à l’importance du refus de l’auteur de se limiter à ce qu’il appelle la « vision analytique », pour laquelle il ne peut y avoir qu’un espace isotrope, où les choses – y compris le corps – sont fortuitement agencées, c’est-à-dire un espace qui n’entretien aucun rapport à ce qu’il y a dans l’espace, n’étant qu’un simple contenant. Même si, dans ses premiers écrits, l’auteur a conditionné la spatialité à une synthèse opérée par le temps, nous démontrons que l’espace en a déjà un intérêt phénoménologique. Avec les ouvrages de sa phase dite « intermédiaire », on voit apparaître un nouveau type de rapport entre le temps et l’espace dans lequel la subordination de l’un à l’autre perd de sa force. Utilisant les notions de profondeur, de schéma corporel et de mouvement, au terme du parcours, nous avons vu que l’espace, toujours présent dans les enquêtes de Merleau-Ponty, y acquiert une centralité, seulement évoquée au début de sa carrière.
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    Estabilização de suspensões aquosas à base de biosilicato
    (Universidade Federal de São Carlos, 2023-07-14)
    Silva, Lucas do Carmo
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    Crovace, Murilo Camuri
    ;
    https://lattes.cnpq.br/2960564171443068
    ;
    https://orcid.org/0000-0002-6993-6363
    ;
    https://lattes.cnpq.br/5103764981192765
    Aqueous suspensions based on particulate bioglasses are frequently used for the production of bioactive glass-ceramic scaffolds. Scaffolds are macroporous structures (with pores between 100 μm and 300 μm) intended for the replacement and repair of flaws in human tissues, something that is possible due to the fact that these structures favor cell penetration and increase vascularization. However, the solubilization of the glass in aqueous media favors the flocculation of the suspension. The effect of this is the compromise of process reproducibility, mechanical properties and the loss of particulate matter. Therefore, it is important to control rheology and stabilize suspensions to prevent flocculation from occurring. Thus, the present study aimed to stabilize aqueous suspensions based on Biosilicate® particles (designated here as BioS), based on electrostatic, steric and electrosteric stabilization mechanisms. For this purpose, the pH of suspensions with different weight concentrations of solids (2.5%, 5.0%, 10.0%, 20.0% and 30.0%) was measured. The use of different dispersants was not able to stabilize the suspensions with 30%w of BioS. As for the suspension of 2.5%w of BioS, the best average zeta potential value was -45 mV, obtained by adding 1.0%w of PAA. Furthermore, there was an attempt to adjust the pH of the 30%w BioS suspension using HCl. Finally, these suspensions were submitted to a qualitative sedimentation test in 25ml graduated burettes, which verified the effectiveness of using 1.0%p of PAA in the stabilization of suspensions of 2.5%p of BioS.
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    Giberela do trigo: viabilidade técnica da integração de estratégias de manejo visando racionalização do uso de fungicidas e redução de micotoxinas
    (Universidade Federal de São Carlos, 2023-07-14)
    Oliveira, Duane Nascimento
    ;
    Jesus Junior, Waldir Cintra de
    ;
    https://lattes.cnpq.br/2614953467362376
    ;
    https://lattes.cnpq.br/4415287424719077
    Fusarium head blight is the most difficult disease to control in wheat, causing damage to grain quality, mainly due to the production of mycotoxins. The current management of the disease is done with the use of fungicides, combined with cultivars with levels of resistance to the pathogen. Thus, the objectives of this study were to evaluate the behavior of the Fusarium head blight and the resulting production of mycotoxins under the management strategies adopted in wheat crops. That way, two cultivars with different levels of resistance to the disease were used, a highly susceptible and moderately resistant cultivar, combined with application or not of fungicide at different phenological stages. The crops were installed in an irrigation pivot area and a rainfed area, being cultivated for two years. For the application (0, 1, 2 or 3) of fungicides (tebuconazole and trifloxystrobin) the pre-anthesis phase; anthesis (moment of anther extrusion) and seven days after anthesis. Thus, through the evaluations carried out following a phenological scale, the FH index (GI - Incidence x severity), damage to the grains (D - % weight loss), weight per unit volume, hectoliter weight (kg/hct ⁻¹), yield calculation (t/ ha⁻¹), concentration (ug/kg⁻¹) and chemotypes of mycotoxins found in the wheat samples were determined. Through the results obtained, the treatments that did not receive fungicide applications showed averages of up to 115.5% higher in (IG) and (D), when compared to the plots that received application. The parameter (kg/hct⁻¹) showed no significant difference between treatments, and the quantitative parameter, tons per hectare (t/ha⁻¹) had averages between 32% and 48.5% higher in treatments with two and three fungicide applications. Applications seven days after anthesis were less efficient when compared to other applications. Mycotoxin concentrations were 14.7% higher in moderately resistant material. The mycotoxin chemotypes found in the samples were: deoxynivalenol (DON), 15-acetyl-deoxynivalenol (15-ADON), 3-acetyl DON (3-ADON) and DON-3-Glc (D3G). In the present study, through the evaluations carried out, a significant difference was found between the fungicide applications in the proposed phenological stages. The treatments were efficient in controlling the disease, not demonstrating the same performance on the production and accumulation of mycotoxins in wheat cultivars.
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    Compósitos de poli(éter imida) com partículas nanoestruturadas de LaNi₅ para armazenamento de hidrogênio
    (Universidade Federal de São Carlos, 2023-07-14)
    Neto, Gabriel Rodrigues de Almeida
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    Beatrice, Cesar Augusto Gonçalves
    ;
    Pessan, Luiz Antonio
    ;
    https://lattes.cnpq.br/8276650236213537
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    https://lattes.cnpq.br/9180232575249975
    Hydrogen is a promising energy vector for decarbonizing the energy matrix, but its widespread use requires safe and efficient storage systems. This study aimed to produce microparticles of polyetherimide with LaNi5 through the process of spray drying for hydrogen storage. The LaNi5 ball-milling conditions were optimized, the effects of the polyetherimide layer on H2 sorption were evaluated, microparticles were produced by spray drying with different LaNi5 contents (60, 70, and 80 wt%), and the H2 sorption properties were improved through chemical modification of polyetherimide. Stable and efficient nanostructured composites for hydrogen storage at room temperature were also produced. The results indicated that LaNi5 milling conditions with a weight ratio of milling sphere:particle of 40:1 for 1 hour and rotation of 250 or 350 RPM led to particles with good sorption and morphological properties without amorphization. Polyetherimide was efficient in accommodating LaNi5 particles during hydrogenation cycles without surface defects or metal particle detachment. The microparticles with 70 wt% LaNi5 achieved a maximum capacity of 0.7 %m during activation and about 0.5 %m after activation, requiring 43 s to reach 80% of their maximum capacity. A significant improvement in the H2 sorption kinetics was observed for the composite with 70% LaNi5 and 11.2% degree of sulfonation of polyetherimide, which also showed the best stability in air, reducing the harmful effects observed for the uncoated particle. While the intermetallic compound did not absorb H2 during the first 40 min of the analysis after 7 days of exposure to air, the composite samples reached their maximum capacity in less than 30 min. The microparticles produced by spray drying showed great potential, allowing the manufacture of microparticles with controlled size distribution, possibly kept constant in different cycles.
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    Estudo sobre o histórico, mineração, aplicações, geopolítica e desafios das terras raras
    (Universidade Federal de São Carlos, 2023-07-14)
    Nishioka, Leonardo Shogi
    ;
    Koga, Guilherme Yuuki
    ;
    https://lattes.cnpq.br/0933095081175012
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    https://lattes.cnpq.br/6462545915769577
    The rare earth elements are essential raw materials for the energy transition that the world is compromised to achieve. Neodymium and praseodymium are fundamental for the manufacture of high performance permanent magnets, which are used for wind turbines and electric vehicles engines. Among the sector challenges, can be cited the wide dominance of the chinese market, corresponding to 90% of the magnets market of the world, additionally, the country indicates that they will supply their internal needs, leaving the Occident with the urge to develop projects capable of supplying this growing demand for the future. Moreover, the manufacturing chain of rare earths is extremely complex, since its mining to its refining and posterior use in its applications. This is because the rare earths are found in low concentrations in the environment, and for its separation, numerous chemical processes with toxic and radioactive reagents and products are involved in the course of its production. In the present study, rare earth concepts, the geopolitics that surround them, companies outside China that look for ways to diversify these raw materials supply, and its perspectives for the future.
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    Marcadores de estresse oxidativo em pacientes internados por COVID-19: estudo de coorte
    (Universidade Federal de São Carlos, 2023-07-15)
    Neves, Fabio Fernandes
    ;
    https://lattes.cnpq.br/2652568399519714
    ;
    https://orcid.org/0000-0001-6536-3249
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    Do the oxidative stress biomarkers predict COVID-19 outcome? An in-hospital cohort study
    (Universidade Federal de São Carlos, 2023-07-15)
    Neves, Fabio Fernandes
    ;
    Pott-Junior, Henrique
    ;
    Yamashita, Kaori Maria Carolina
    ;
    Santos, Sigrid de Sousa
    ;
    Cominetti, Marcia Regina
    In SARSCoV-2 infections, excessive activation of the immune system dramatically elevates reactive oxygen species levels, harms cell structures, and directly increases disease severity and mortality. We aimed to evaluate whether plasma oxidative stress biomarker levels could predict mortality in adults admitted with Coronavirus Disease 2019 (COVID-19), considering potential confounders. We conducted a cohort study of 115 adults (62.1 ± 17.6 years, 65 males) admitted to a Brazilian public hospital for severely symptomatic COVID-19. Serum levels of α-tocopherol, glutathione, superoxide dismutase, 8-hydroxy-2′-deoxyguanosine, malondialdehyde, and advanced oxidation protein products were quantified at COVID-19 diagnosis using real-time polymerase chain reaction. Serum levels of α-tocopherol, glutathione, superoxide dismutase, and advanced oxidation protein products differed significantly between survivors and non-survivors. Serum glutathione levels below 327.2 μmol/mL were associated with a significant risk of death in COVID-19 patients, even after accounting for other factors (adjusted hazard ratio = 3.12 [95% CI: 1.83–5.33]).
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    Estágios imaturos de Palyadini (Lepidoptera, Geometridae) e seus parasitoides associados a Myrsine umbellata Mart. (Primulaceae) em áreas de Cerrado em São Carlos, SP
    (Universidade Federal de São Carlos, 2023-07-17)
    Rodrigues, Elizabeth Moreira
    ;
    Penteado-Dias, Angélica Maria
    ;
    https://lattes.cnpq.br/8637344058859147
    ;
    https://orcid.org/0000-0002-8371-5591
    ;
    Dias Filho, Manoel Martins
    Tritrophic interactions are those that involve relationships between three trophic levels: producer, primary consumer and secondary consumer. They are considered complex, since they involve physical-chemical regulatory mechanisms, in addition to high dependence or susceptibility to each other. Thus, changes in the habitat or in other living conditions of any of these groups can cause an imbalance that will extend to the others. The Cerrado biome, the second largest biome in South America, is mainly made up of savannas. Due to human action, mainly through arson, the biome undergoes major changes, affecting many species. The species Myrsine umbellata Mart. (Primulaceae) (producer), in abundance in the Cerrado Biome, has ecological importance, being indicated for the recovery of degraded areas of grassland or secondary vegetation because it is a pioneer. The Primulaceae family, according to the literature, is closely associated with Palyadini larvae (Geometridae: Ennominae) (primary consumer), while the Hymenoptera parasitoids (secondary consumer) stand out for controlling populations of other insects that interfere with food chains. However, studies involving taxonomic and bionomic knowledge regarding the Neotropical fauna of Lepidoptera (Geometridae) and Hymenoptera parasitoids associated with the Primulaceae family are scarce. Thus, this work aimed to characterize the immature stages of Neotropical Geometridae species associated with Myrsine umbellata (Primulaceae) collected in Cerrado areas of the Federal University of São Carlos, São Carlos, SP - Brazil, aiming at the taxonomic and bionomic knowledge of the group; in order to contribute to the knowledge of the immature stages of Palyadini (Geometridae: Ennominae), including their morphology, bionomic aspects and associated parasitoids. As a result, the areas presented a richness of Geometridae larvae equal to 496 individuals, where the species Phrygionis polita Cramer, 1780 and Argyrotome paraguayaria Schaus, 1927 presented greater abundance and higher parasitism index, respectively. Glyptapanteles sp. (Hymenoptera, Braconidae, Microgastrinae) and Euplectrus sp. (Hymenoptera, Eulophidae), with a gregarious habit, were the genera with the highest abundance of emerged adult parasitoids. While Casinaria spp. (Hymenoptera, Ichneumonidae, Campopleginae) presented greater diversity of morphospecies. Also, the first record of Distatrix flavus Rodrigues, Dias & Penteado-Dias, 2023 was obtained. Finally, the communities of both Geometridae larvae and their parasitoids present in the Cerrado Y of UFSCar, a preserved Cerrado area, showed greater diversity, consequently lower levels of equitability when compared to the communities of Geometridae larvae and their parasitoids present in the Trilha da Natureza, São Carlos, SP, Cerrado area recovering after fire.
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    O papel das políticas públicas no desenvolvimento de sistemas agroflorestais no Brasil
    (Universidade Federal de São Carlos, 2023-07-17)
    Ballerini, Ariel Pollo
    ;
    Aguiar, Danilo Rolim Dias de
    ;
    https://lattes.cnpq.br/1889207481986151
    ;
    https://orcid.org/0000-0001-9791-9774
    ;
    https://lattes.cnpq.br/2634809737541030
    Climate change is a reality and its effects directly affect society, including the production of food and commodities. Given this scenario, the need to face the consequences of climate change leads to studies to verify alternatives for agricultural production that are sustainable and compatible with contemporary reality. Agroforestry systems (AFS) have socioeconomic and environmental benefits, and are the subject of international studies that evaluate the factors that determine their success. In order to be successful in the implementation of SAFs, and maximum use of their advantages, it is necessary that the State acts in the regulation of markets, in the incentives to the use of the technique through credit lines and payment for environmental services, among other aspects that are up to it. In this sense, the objective of this work is to identify the role that public policies play in the development of SAFs in Brazil, highlighting the programs and laws that contemplate national agriculture and that have an impact on the expansion of the use of agroforestry. Brazil has a legal framework that puts sustainability in agriculture on the agenda, as well as programs that propose investments in agroforestry, but there is no direct and specific direction of public effort for the development of SAFs in the country.
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    Fotodegradação de contaminantes emergentes por catalisadores à base de PHI (Poli Heptazina Imida)
    (Universidade Federal de São Carlos, 2023-07-17)
    Pastana, Vitor Gabriel da Silva
    ;
    Teixeira, Ivo Freitas
    ;
    https://lattes.cnpq.br/9782517948999001
    ;
    https://lattes.cnpq.br/3569736875764585
    ;
    https://orcid.org/0000-0001-7587-6603
    The remediation of pollutants promoted by systems that are cheap and viable remains an important challenge in the field of catalysis. Carbon nitrides applied in photocatalytic systems are a promising class of materials for promoting advanced oxidative processes, with several studies demonstrating their potential in removing contaminants. In the work that follows, rifampicin and tetracycline, two antibiotics with latent human and environmental toxicity, were photodegraded/removed by Fe-PHI, a crystalline carbon nitride with potential applications in oxidative reactions. The synthesis of the material followed the processes reported in the literature. Unlike other orders of the class, the PHI has cations inserted between the heptazine structures, which can be exchanged for other transition metals, being classified in certain cases as single-atoms, catalytic sites with good activity and stability. The obtained catalysts had their structure analyzed by DRX, FT-IR, HR-TEM and EXAFS. Contaminants were reserved in aqueous solution and their respective photodegradations/adsorptions were monitored by spectroscopy in the UV-Vis region (~80% removal), being almost 100% remedied in the subsequent irradiation. Tetracycline, once more durable in the medium, displayed around 65% of remediation in 8 hours of irradiation with Fe-PHI and neutral pH. The catalyst recycles showed continuous activity, for both sorption and photoremediation. With such a prolonged activity, in addition to its simple synthesis, carbon nitrides have shown promise in the application of contaminant removal.