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A contribuição da associação entre genealogia acadêmica e bibliometria para a avaliação de Programas de Pós-Graduação
(Universidade Federal de São Carlos, 2020-07-28) Moura, Vanessa Paula Alves de; Faria, Leandro Innocentini Lopes de; https://lattes.cnpq.br/0767710394930118; https://lattes.cnpq.br/3872545944819214
The measurement of scientific production is an object of studies much explored in Information Science, through Bibliometrics, which allows to evaluate the performance of researchers and the impacts of their productions, and have the results bibliometric indicators, which are useful to understand reality and act in different situations. Technological evolution allowed the improvement of Bibliometrics and has also benefited other studies, such as Academic Genealogy, which, more recently, has been used to analyze the performance of researchers and the impacts of their actions on Science, through the relationship between supervisor and its oriented. One of the most recent studies in Brazil on Academic Genealogy, is based on the Lattes Platform and the extraction of these data is done by software called AGLattes, developed by researchers in the field of Computer Science. Although the data obtained are rich and valuable, there is little research that uses them for the purpose of complementing bibliometric indicators. Therefore, this study aims to investigate whether the application of Academic Genealogy and bibliometric analysis together can bring relevant information about the contribution of a Postgraduate Program in the training of researchers and in the production of knowledge. For the execution of the research, the Postgraduate Program in Materials Engineering of the Federal University of São Carlos - PPGCEM/UFSCar - was chosen, which originated in the first course of Materials Engineering in Brazil. The analysis was made from all teachers which are in the program since its foundation, a total of 58 teachers. As these professors work in other programs, a procedure was developed that made it possible to reach only researchers who have their origin in PPGCEM/UFSCar, eliminating the contamination of data from other programs and allowing to obtain information from 993 direct and 1205 indirect descendants. To extract the scientific production of the Lattes Curriculum of these descendants, the software Lattes Machine was used and later data mining and bibliometric analyzes were performed using the VantagePoint software. The results are illustrated by bibliometric indicators built from the association of Academic Genealogy with Bibliometrics, which provide valuable information about the program, the human resources trained and all their descendants, such as where they work, how they are distributed around the world and in Brazil, the training area, in addition to information about its scientific productions that can be used in the elaboration of strategies, in the self-assessment of graduate programs aiming at guaranteeing the quality and obtaining resources from development agencies, in this case the CAPES. The study also contributes to verify the historical and current importance of PPGCEM/UFSCar and its researchers for the program area and for Science.
Estudos teóricos e experimentais de complexos de cobre: propriedades espectroscópicas e atividade biológica
(Universidade Federal de São Carlos, 2020-07-28) Oliveira, Herisson Faustino Santos de; Aguiar, Inara de; https://lattes.cnpq.br/8419273145052566; Rocha, Fillipe Vieira; https://lattes.cnpq.br/5841127259122766; https://lattes.cnpq.br/7782479943277002
Cancer is the second leading cause of death in the world. The scientific community is mobilizing to study new compounds with cytotoxic potential and that can be used as molecular probes. However It is important to highlight that for every 100 thousand drug candidates synthesized, only one gets to the final clinical phase. One of the challenges of medicinal chemistry is to optimize the rate of success, increasing the efficiency of the process. In this context, polypyridic ligands act as good options, once when they are coordinated to a metallic center, their complexes can put together crucial structural features to promote their use as biological probes, due a visible bands, resulted of a charge transfer, and cytotoxic agents by intercalation with DNA. In this work, a theoretical investigation by DFT and TD-DFT of Cu II and Cu I complexes was carried out on their structural and spectroscopic properties. Cu II polypyridinics complexes were synthesized and characterized by UV-Vis, NMR, elemental analysis, fluorescence spectroscopy, conductivity and cyclic voltammetry. Data showed absorption and emission ranges above 400 nm, with quantum emission yield values compared to the literature standard [Ru(Bipy)3]2+. The IC50 values towards MDA-MB 231, MCF7 and PNT2 cell lines surpass the cytotoxicity of cisplatin. Ethidium bromide displacement assay showed that all compounds interacted to the DNA molecule and the molecular docking studies demonstrated the capacity of the compounds to act as DNA intercalating agents. Thus, the work indicated the potential of Cu II complexes as active biological agents, both with high cytotoxicity and luminescent properties.
Identificação assistida por docking molecular de potenciais alvos em Plasmodium falciparum para derivados de indol-3-glioxiltirosina com atividade antimalárica in vitro
(Universidade Federal de São Carlos, 2020-07-28) Dávila Rodríguez, María José; Caracelli, Ignez; https://lattes.cnpq.br/8956527354576143; Schpector, Júlio Zukerman; https://lattes.cnpq.br/4252331837170383; https://lattes.cnpq.br/7409614784274265
Malaria, although it is no longer considered a neglected disease, remains a public health problem. In 2018 alone, the World Health Organization estimated 228 million new cases and 405,000 deaths worldwide. Currently, chemotherapy is the only strategy available for the treatment of this disease. However, the emergence of resistance from Plasmodium spp. to the available antimalarials makes it necessary and preeminent to develop new drugs to treat it. In this sense, the in vitro activity against Plasmodium falciparum, in the intraerythrocytic stage, of a series of indole-3-glyoxyl tyrosine derivatives are described in the literature. As in recent years, computer-aided methods for drug development have made great advances, being commonly integrated into the preclinical development phase, their use was applied to try to unveil their mechanism of action and/or target which is unknown. In this work, we employ inverse virtual screening based on molecular docking to identify potential targets for the indole-3-glyoxyl tyrosine derivatives. In total, 34 different enzymes from Plasmodium falciparum, with structures available in the Protein Data Bank, were evaluated in detail using molecular docking simulations. Besides, molecular dynamics simulations were used to study the stability of the protein-ligand complexes considered to be promising leads. The results indicated the enzymes dihydroorotate dehydrogenase (DHODH) and plasmepsin II (PMII), of Plasmodium falciparum, as potential targets. The docking simulations showed that the most active compounds would be able to establish the key non-covalent interactions needed for target inhibition, that is, the docking results agree with the experimental values of the antiparasitic activity. Molecular dynamics was used to study the stability of protein-ligand complexes in a situation that simulates biological conditions. All of these results show that the methodology described here can be used in the optimization of the indole-3-glyoxyl tyrosine derivatives aiming at increasing their antiplasmodial activity.
Formação de hexaluminato de cálcio in situ em refratários macroporosos: caminhos para o desenvolvimento de isolantes térmicos mais eficientes e ecológicos
(Universidade Federal de São Carlos, 2020-07-28) Borges, Otávio Henrique; Pandolfelli, Victor Carlos; https://lattes.cnpq.br/7369376873984839; https://lattes.cnpq.br/3641422282209414
Macroporous thermal insulators have recently emerged industrial interest due to their low thermal conductivity and toxicity compared to fiber-based insulators. Nonetheless, some challenges need to be overcome to enable a widespread application of this material. To face some of those, the effects of adding distinct Ca2+ sources and concentrations in alumina-based macroporous ceramics, were evaluated. Initially, the decrease of onset strengthening temperature (TS) induced by CaCO3 was investigated, and a likely mechanism to explain it was proposed. This mechanism allowed to infer that other Ca2+ sources, as Ca(OH)2 and CaO, would act similarly. This hypothesis was later confirmed. Additionally, reduction of shrinkage after firing were detected due to hibonite (CA6) formation induced by the presence of these Ca2+ sources. Ca(OH)2 and CaO could not be used in high concentrations without reducing the material porosity due to their effect on the ceramic suspension. However, this phenomenon was no observed for CaCO3, which could be used to produce an insulator with high porosity, linear expansion of 1% after firing at 1600ºC for 5h and thermal conductivity of 0.63Wm-1K-1 at 1200ºC. Finally, SiO2, TiO2 or ZnO in amounts varying from 0.6mol% to 2.8mol%, were evaluated as mineralizing agents. This analysis showed that the two latter allowed complete CA6 formation at, respectively, 1300ºC and 1400ºC rather than 1600ºC. Additionally, ZnO induced the development of CA6 with a higher aspect ratio without reducing the material's refractoriness. Thus, at the end of this work, it was possible to produce an in-situ macroporous thermal insulator comprised by acicular CA6 at 1300ºC, presenting high porosity (83%), zero shrinkage after firing at 1600ºC for 5h, TS of 680ºC and thermal conductivity of 0.55Wm-1K-1 at 1200ºC. Thereby, it is expected that the use of such material could help energy-intensive industries to improve their efficiency, reducing environmental impacts and production costs.
Produção de recobrimentos resistentes ao desgaste através de laser cladding de pós das ligas amorfizáveis fe-co-nb-b-(y)
(Universidade Federal de São Carlos, 2020-07-28) Lucena, Felipe Amélio de; Afonso, Conrado Ramos Moreira; https://lattes.cnpq.br/2176215981291453; https://lattes.cnpq.br/0474221317198742
Industrial components can be subjected to a high level of surface wear it necessary to search for new wear-resistant alloys to improve the performance and safety of the components. The objective of this work was to produce laser coatings with high hardness and high wear resistance. Three new vitreous alloys of the Fe-Co-Nb-B-Y system were produced in the arc furnace integrated with the suction system using commercial raw materials (Fe-Nb and Fe-B ferroalloys). Subsequently, through the high energy milling process of the splat plates (> 10 cm) generated during gas atomization, powders (∅ <45 μm) were formed for Fe66Co7Nb4B23 and Fe63Co7Nb4B23Y3 (% at.) alloys. Three different coatings (B, C and D) were produced using the Fe66Co7Nb4B23Y3 (% at.) alloy and one coating (A) for the Fe66Co7Nb4B23 (% at.) alloy for comparison. Each coating was produced using different laser parameters and the powders from the milling. The coatings were subjected to the wear test of pin on disk and Vickers hardness. The “A” coating showed a lower average value of the specific wear rate (2.20 x10-5 mm3/Nm) and a higher average value of the friction coefficient (≈ 1.15) compared to “B” coating. The laser remelting process applied over “C” coating and the addition of a second coating layer in the formation of “D” coating did not significantly change its specific wear rates, which were similar in “B” coating (10.9 x 10-5 mm3/Nm). The friction coefficient of “B” coating (≈ 0.5) increased to ≈ 0.7 after its laser remelting for the formation of “C” coating and decreased to ≈ 0.35 in “D” coating with the addition of a second coating layer. The laser cladding process allowed the production of coatings with high hardness (575 ± 60 to 1160 ± 80 HV).
Descrição de um novo gênero de aranha Neotropical da família Ctenidae Keyserling, 1877 (Araneae: Lycosoidea)
(Universidade Federal de São Carlos, 2020-07-28) Pereira, Maria Paula; Polotow, Daniele; https://lattes.cnpq.br/8215172202694229; Labarque, Facundo Martín; https://lattes.cnpq.br/7227934929457482; https://lattes.cnpq.br/5207346088499616
The Neotropical region exhibits surprising quantities of spider diversity, with Brazil having the greatest number of described species. The family Ctenidae Keyserling, 1877, is within the ten most diverse families in Brazil. Despite the hundreds of species records for the family, the phylogenetic limits inside and outside the family level are not yet fully defined and recent studies agree with the Ctenidae polyphyly as currently delimited. Also, the subfamily Cteninae, which comprises the genus type Ctenus , was recovered as polyphyletic, as well as the genus, in recent analysis. Authors argue that to achieve the monophyly of these groups, several genera must be described to group the various species out of place and the new species to be described. The present work describes a new Neotropical genus of the family Ctenidae, to accommodate three new species found in the state of Pará, northern Brazil: Bulboctenus kayapo sp. nov. , Bulboctenus itunaitata sp. nov. and Bulboctenus munduruku sp. nov.
O jogo didático Isogames no estudo da isomeria em compostos orgânicos: indícios de aprendizagem
(Universidade Federal de São Carlos, 2020-07-28) Barbosa, Vivian Marina; Zanon, Dulcimeire Aparecida Volante; https://lattes.cnpq.br/1811225448261362; https://lattes.cnpq.br/4363029727115518
Historically, the traditional approach about contents has been criticized for its limitations regarding to the scientific knowledge. In this conception, Science is decontextualized and uncritical. Therefore, the teaching and learning contribute just a little to keep the interest and motivation in students. In this sense, this research aimed to identify the evidence of learning about isomerism in organic compounds, based on the execution of the educational game called ISOGAMES, based on problem solving and interdisciplinarity. The interest in the study of the theme arose from the analysis of my own practice, because, several times, the students had difficulty understanding concepts related to isomerism. Thus, this research was guided by the following question: Which evidences of learning, about isomerism in organic compounds, can be identified, through the execution of the educational game ISOGAMES, based on problem solving and interdisciplinarity? To get to this, the qualitative research involved the participation of forty sophomore high students of the full time Chemistry course, in one of the Technical Schools (ETECs) in the state´s countryside of São Paulo. The game itself was used for obtaining and analyzing the datas themselves; it was used Concept Maps (MCs) to the themes like adrenaline, aspartame, trans fat and vitamin C; the speeches of the involved ones and the answers to the problem questions. To identify the evidence of learning were analyzed the MCs built by the participants and, using the same resource were created MCs for each of the themes. It was indentified three categories, namely: development of criticality; disciplinary conceptual understanding (isomerism; enantiomers) and, finally, construction of interdisciplinary and contextual meanings about isomerism in organic compounds. The results indicated that the educational game ISOGAMES revealed contribution and potential for learning concepts about isomerism in organic compounds, since it was conceived from an interdisciplinary and investigative perspective. As an educational product resulting from this Dissertation, this game reflects the relationship between theory and practice and the breaking of disciplinary boundaries.
Astronomia e Educação Ambiental: uma proposta na busca pela consciência planetária
(Universidade Federal de São Carlos, 2020-07-28) Silva Neto, Natan Pires da; Bretones, Paulo Sérgio; https://lattes.cnpq.br/0016646045895716; https://lattes.cnpq.br/3482022072069939
The objective of this research is to investigate the application of Astronomy contents in Environmental Education (EE) and to contribute to the development of planetary or ecological awareness. For this purpose, an intervention study of experimental nature was developed. A didactic sequence in Astronomy was proposed to contribute to the development of ecological awareness among students. Initially, a bibliographic review of theses and dissertations, articles published in journals, and works presented in selected events was carried out. Qualitative data was analyzed in order to investigate the characteristics of pedagogical practices, the acquisition of knowledge, and the involvement and participation of students in the production of the proposed activities, such as thematic workshops. With the activities, it was possible to detect the acquisition of knowledge and the increase in students’ vocabulary related to astronomical concepts. It was also noted that astronomical scientific knowledge contributes to the development of ecological awareness, considering the interface of these areas as a motivation for students to incorporate them to their daily lives and to improve environmental discussions. The environment is addressed as an important resource for the survival of all living beings, and EE is approached as a teaching and learning process to raise awareness in the preservation and conservation of these resources. The Astronomy content was developed from the individual's vision and perception. The Solar System was discussed as a portion of the Universe with pedagogical strategies in the practice of activities. These activities used a topocentric approach and a holistic perspective. Through classroom discussions, during the stages, the development of ecological awareness was evidenced using the multidisciplinary potential of Astronomy. The didactic sequence motivated the students and contributed to the understanding of human belonging to the planet and of responsibility with the environment.