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Influência do intemperismo da Região Amazônica nas propriedades físicas e mecânicas da madeira Angelim- Vermelho na cidade de Porto Velho
(Universidade Federal de São Carlos, 2024-11-06) Pessôa, Poliana de Melo; Almeida, Diego Henrique de; https://lattes.cnpq.br/7043956540589502; https://orcid.org/0000-0002-6220-4004; https://lattes.cnpq.br/8927885751118440; https://orcid.org/0009-0004-7201-1945
Despite the advantages of wood, it is common to use it in environments subject to exposure to biotic and weathering factors, causing its natural manipulation, damaging physical and especially mechanical properties of interest, which can affect the useful life of buildings. In this context, the largest reserve of biological diversity in the world is found in the Amazon. However, although this region has great potential to produce native woods, the sector is still predominantly dominated by the Eucalyptus and Pine species. In addition, weathering varies according to the season and location, which implies that the climatic conditions of the Amazon region can be even more aggravating to the handling of wood compared to other regions, due to its climatic characteristics, as it has a hot and humid climate, with two well-defined seasons, one dry and one rainy, since in the latter, precipitation occurs in intense forms. Therefore, it is necessary to conduct studies on the action of weathering in the Amazon region on native woods, to evaluate and determine the importance of decreases in mechanical properties, since these can even reduce the resistance class imposed in the project. Thus, the present research project aims to evaluate the influence of the action of weathering in the Amazon region in Porto Velho, Rondônia, on the physical and mechanical properties of Angelim-Vermelho wood (Dinizia excelsa Ducke), by exposing specimens of the wood in question to natural weathering, and subsequently evaluating, through laboratory tests, its physical properties of colorimetry and density, and mechanical properties of hardness, modulus of elasticity parallel to the fibers and resistance to joint parallel to the fibers. In addition, a systematic literature review was carried out to verify the effects of weathering on wood found in the literature. From statistical analyses it was possible to verify that despite causing damage to the physical and mechanical properties of the wood, weathering does not significantly manipulate the wood under study in the time delimited for this research, with the exception of the colorimetry and hardness properties parallel to the fibers, making it necessary to extend the exposure time in order to correctly verify its behavior in the face of the climatic factors of the Amazon region.
Óleos essenciais de tangerinas para manejo de podridão floral dos citros (Colletotrichum abscissum)
(Universidade Federal de São Carlos, 2024-11-06) Zunkeller, Andreza Bonetto; Bastianel, Marinês; https://lattes.cnpq.br/2523177587459092; Schinor, Evandro Henrique; https://lattes.cnpq.br/2162760988837984; https://lattes.cnpq.br/3250299805016727
Citrus farming in Brazil has been facing phytosanitary problems that lead to significant production losses, among which postbloom fruit drop (PFD) caused by the fungus Colletotrichum abscissum stands out. This study aimed to investigate the action of tangerine essential oils (EOs) on the fungus C. abscissum for the management of CBF. EOs of three tangerine varieties: IAC 2019Maria mandarin, Murcott IAC 221 tangor and Late IAC 585 willowleaf, extracted from unripe and ripe fruits at different dosages (0; 2; 4; 8; 16 and 32 (µL mL-1) were evaluated for the percentage of inhibition of mycelial growth, speed index and area under the mycelial growth curve, sporulation and germination of in vitro spores of the fungus C. abscissum. In addition, the chemical components present in the EOs and the yield and their relationship to the diameter of the fruits and peel thickness were verified. Given the results found in vitro, the disease control capacity in detached flowers of Tahiti acid lime was analyzed, in addition to the potential of the EOs to activate defense mechanisms in plants, by the action of peroxidase, polyphenol oxidase and phenylalanine ammonia-lyase. Limonene was the main compound found in the EOs of tangerines extracted from unripe and ripe fruits. It was observed that the Late IAC 585 willowleaf presented a higher EO yield when extracted from unripe fruits. There was a positive correlation between yield and epicarp thickness of the peel for both EOs from unripe and ripe fruits. In the in vitro test with EOs extracted from unripe fruits, the Late IAC 585 willowleaf demonstrated a greater capacity to inhibit mycelial growth and when using the EO extracted from ripe fruits, the IAC 2019Maria mandarin was more efficient in controlling the pathogen. The EOs of both varieties were effective in controlling sporulation when extracted from unripe fruits. For ripe fruits, there was a difference only between dosages, with a sharp decrease in the number of conidia with increasing dosage. The EO of the IAC 2019Maria mandarin stood out for presenting control of spore germination at lower doses, when compared to the other varieties, for both unripe and ripe fruits. When applied to detached flowers, the EO had no systemic action on the flowers to prevent C. abscissum infection, in addition to not having the ability to activate the plant's defense mechanisms.
Estudos in silico dos modos de ligação dos hormônios tireoidianos T3 e T4 com a Proteína Transportadora Albumina Sérica Humana HSA
(Universidade Federal de São Carlos, 2024-11-06) Barbosa, Elisa Guimarães; Freire, Thales Souza; https://lattes.cnpq.br/0320608221793070; Caracelli, Ignez; https://lattes.cnpq.br/8956527354576143; https://lattes.cnpq.br/7139839105851251
In the present work, the binding mode and molecular interactions between thyroid hormones (T4, T3 and the positional isomers of T3 – T3IP) and the transporter protein (HSA) were investigated. T4 has 4 iodine atoms and T3 has 3. Analysis of the crystallographic structures of the T4-HSA complexes (1HK1,1HK2-R218H, 1HK3-R218P - with fatty acids and 1HK4, 1HK5-R218H- without fatty acids) was carried out. The knowledge acquired was used in the study of molecular docking to understand T3 since there is no crystallographic structure of HSA with T3, with T3 being the active form of thyroid hormone in target cells. It was observed that HSA is capable of differentiating T4 from T3. Another important point was to study 3 cases of HSA-T4 and HSA-T3 complexes, R128, R218H, R218P and explain the difference in HSA-hormonal ligand affinity. In the case of the T3 ligand, which has 3 iodine atoms, with a specific position, 4 positional isomers, T3IP, were evaluated. Docking studies showed that these compounds are different compared to HSA. The presence of fatty acids in the crystallographic complexes of the native protein and R218H mutant protein affected the availability of binding sites, limiting the interaction with T4 to a single site (Cleft). The analysis of T3 positional isomers (T3IP) showed that the structural flexibility of the ligands is an important factor in determining interactions with HSA. The findings of this study can be applied in the development of therapeutic strategies aimed at transporting thyroid hormones in conditions of genetic mutations or metabolic disorders. Detailed understanding of the differences in affinity between T3 and T4 and the influence of mutations in HSA provides a solid basis for future research focused on modulating the bioavailability of these hormones. The results presented here serve as a starting point for experimental investigations that can validate the trends observed in silico studies and explore new applications in the field of endocrinology and biotechnology.
As diferentes perspectivas da pediatria a partir das vivências de uma acadêmica de medicina: uma narrativa reflexiva
(Universidade Federal de São Carlos, 2024-11-06) Nogueira, Marina Mourad; Germano, Carla Maria Ramos; https://lattes.cnpq.br/1685750854841732; https://orcid.org/0000-0001-5030-7164; Stefane, Claudia Aparecida; https://lattes.cnpq.br/7808406751232968; https://orcid.org/0000-0003-2090-4878; https://lattes.cnpq.br/6455919165301977; https://orcid.org/0009-0002-6831-5773
The word “pediatrics” is of Greek origin, formed by the combination of the terms paidos, which means “child” and iatreia, which means “healing process”, and is used to name the medical specialty dedicated to child care, from birth to adolescence. Since the end of the 19th century, teaching Pediatrics gained prominence in Brazilian medical training, remaining until today as one of the great areas of learning. The medical course at UFSCar includes in its pedagogical project the broad area of child health and of the adolescent, to be studied during the 6 years of graduation. Therefore, The objective of this work is to demonstrate the impact of different experiences on pediatrics throughout a degree in medicine and demonstrate the importance of this specialty in medical and humanitarian training.