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Áreas de risco para a disseminação da febre amarela em São Paulo: como a estrutura da paisagem influencia a abundância e a conectividade funcional para Haemagogus spp
(Universidade Federal de São Carlos, 2023-12-08) Prado, Amanda Francisco; Prist, Paula Ribeiro; https://lattes.cnpq.br/6937654389242222; Freitas, Patrícia Domingues de; https://lattes.cnpq.br/5647631868534064; https://lattes.cnpq.br/4339096103530947
Wild yellow fever (WYF) is a high lethality infectious disease for humans and some non-human primates (NHP). It is caused by Flavivirus that have the mosquitoes Haemagogus leucocelaenus and Haemagogus janthinomys (Culicidae:Diptera) as primary vectors in the Atlantic Forest. Both species are considered acrodendrophiles and common in forest fragments, but have different tolerances to habitat degradation. Previously endemic to the Amazon region, WYF has recently spread throughout Brazil. In São Paulo state, the last WYF outbreak began in 2016 in the northwest region and, from 2017, the virus spread to the eastern part of the state, possibly through ecological corridors or stepping stones, causing a large decline in threatened PNH species and having a large impact on public health. Virus transmission risk is mainly related to vector abundance. However, despite of several efforts, little is known about vector ecology requirements, particularly on how landscape parameters affect their abundances and functional connectivity for them, which allows virus spread to other regions. Therefore, the goals of this study were (1) to analyze how and at what scale the landscape structure affects Hg. leucocelaenus and Hg. janthinomys abundance in São Paulo state, (2) based on their ecology, identify connecting elements that possibly were used by the vectors in the last outbreak and (3) indicate areas with greater risk of WYF vector dispersion. For this, we used vector abundance data collected in 24 points of native vegetation areas in São Paulo northwest and a model selection approach, with landscape metrics at different scales (from 500 m to 2.5 km) as predictor variables. Based on the best selected model, the abundance of each vector was extrapolated to the entire state and overlapped with a potential functional connectivity map developed for each species. The abundance of Hg. leucocelaenus responded to the landscape structure mainly at the 2.0 km scale and the results suggest that increases in the forest cover amount with high fragmentation levels tend to increase the abundance of this species. The abundance of Hg. janthinomys responded to the landscape structure mainly at the largest scales (2.5 km) and results suggest that this species is less abundant in fragmented and degraded landscapes, is more related to core areas of native vegetation fragments and may be more related to Cerrado areas than Hg. leucocelaenus. The areas with greatest risk for virus spread were mainly concentrated on the upper edges of Serra do Mar, in the Serra da Cantareira region, in the peripheral areas of São Paulo metropolitan region and in Vale do Paraíba, due to the greater estimated vector abundance and high functional connectivity observed. Core areas of large forest fragments showed a lower risk of virus spreading. Thus, the fragmented landscapes of São Paulo present several characteristics that result in a high risk of occurrence and WYF spread, including in areas close to large urban centers, raising the alarm of WYF reurbanization. Therefore, the maintenance and recovery of forest areas in a non-fragmented state is essential to prevent new WYF outbreaks, as well as the inclusion of multiscale analysis in the epidemiological surveillance routine and animal health services, to more accurately estimate the potential dispersion routes of the virus.
Modelagem via redes neurais de dados de sobrevivência de longa duração com dispersão não observada
(Universidade Federal de São Carlos, 2023-12-08) Teh, Led Red; Cancho, Vicente Garibay; https://lattes.cnpq.br/3503233632044163; https://lattes.cnpq.br/7592000878389363
Traditional models in survival analysis assume that every subject will eventually experience the event of interest in the study, such as death or disease recurrence, so the survival function is said to be proper. Cure rate model, which was first proposed seven decades ago, has since been used to account for the presence of cure fraction, this means that a certain fraction of the individuals will never experience the occurrence of an event of interest for which they can be treated as immune or cured subjects in the context of cancer treatment. In the literature, various cure rate models have been widely studied and commonly applied to structured data with small quantities of covariates. The use of convolutional neural network, a powerful deep learning technique for image processing problem, has become increasingly more common in the medical field in recent years. Medical images such as histological slides and magnetic resonance images (MRIs) are directly related to a patient's prognostic factors, therefore, it is reasonable to introduce these images as predictors in cure model. In this work, we extend upon the article of Xie and Yu (2021b) in which a neural network was used to model the unstructured predictor's effect in the promotion time cure model's setting to the cases of overdispersed data. We will call our extension as integrated negative binomial cure rate model, and its parameters will be estimated through the Expectation-Maximization algorithm.
Pesquisa-ação: estudo bibliométrico de artigos científicos indexados na base de dados Educ@
(Universidade Federal de São Carlos, 2023-12-08) Silva, Fernando Xavier; Hayashi, Maria Cristina Piumbato Innocentini; https://lattes.cnpq.br/7263318849588556; https://orcid.org/0000-0003-1250-3767; https://lattes.cnpq.br/9581628872265605; https://orcid.org/0000-0001-7379-8541
This is a bibliometric study on action research. Action research is a research method with various definitions and investigation procedures. It is a type of collaborative and emancipatory scientific research that involves social action carried out by the stakeholders themselves. Given the specific nature of action research, a review of articles on this method proved to be an important scientific contribution. The key contribution of bibliometric research is the verification of impact, as this type of research aims to gauge, measure, analyze, for example, the number of publications, citations, the degree of circulation in scientific and strictly political environments. The general objectives were: To analyze the characteristics of academic production in articles with the theme of action research hosted on the Educ@ platform; To analyze the citations of the articles by means of a bibliometric study. The specific objectives were: a) To carry out a historical reconstruction and theoretical foundation of action research on the concept of action research and the fundamental works on this subject in order to contextualize the current state of the field. This bibliometry indicated that Price's index according to which 50% of academic production in a given field is carried out by the square root of the total number of authors could not be verified, as √ of 2013 authors (including theses, dissertations, articles, book chapters and books) is 45. The 45 authors together produced 318 works, which corresponded to 22.5% of the total of 1409 productions. Most of these were produced in the 2000s, with 616 studies (43.7% of 1409). It was also concluded that the bibliometrics of the articles provided a general picture of the studies that used action research as a method, and that some characteristics indicate the potential contribution of this method to education, both in teacher training and in raising awareness of issues such as race, gender and the environment. On the other hand, it is a method that is constantly being re-evaluated and undergoing debate in the scientific field.
Eletromobilidade: estado atual dos veículos elétricos e das baterias de íons lítio (BILs)
(Universidade Federal de São Carlos, 2023-12-08) Moreira, Nathan dos Santos; Bocchi, Nerilso; https://lattes.cnpq.br/5930614700886481; https://lattes.cnpq.br/5606563001971845
Electric vehicles are characterized by having an electricity-powered motor whose energy comes from a battery or a fuel cell. A variety of health and environmental problems are linked to the emission of greenhouse gases from fossil fuel combustion. These concerns, combined with the fluctuation in oil prices, have significantly boosted the electric vehicle sector in recent years to replace internal-combustion-engine vehicles, requiring the development of batteries that offer high autonomy and driver safety. Among these devices, lithium-ion batteries exhibit higher energy and volumetric density as well as a long life cycle. Thus, this work aims to conduct a literature review on lithium-ion batteries, evaluating their prospects and challenges. Additionally, the most recent data on electric vehicles in both Brazil and world will also be presented.
Nanocarreadores biopoliméricos de isoflavonas de soja e óleos essenciais: potencial dermocosmético, fotoprotetivo e antimicrobiano
(Universidade Federal de São Carlos, 2023-12-08) Santos, Eduarda Oliveira dos; Forim, Moacir Rossi; https://lattes.cnpq.br/1234565160573730; https://lattes.cnpq.br/9921184973069169; https://orcid.org/0009-0007-4748-6764
With the emergence of healthier and more conscious lifestyles, the cosmetics market has undergone a significant shift in chemical reformulation and technological planning. Plant extracts and essential oils stand out, as their components can exhibit more than one of these characteristics simultaneously and act synergistically. The strategy of converting regular materials into nano-scale formulations for cosmetics lies in formulating products with a high penetration power into the skin layers. Thus, this study aims to evaluate the potential of secondary metabolites found in soybean seeds (Glycine max) and commercially sourced essential oils (Geraniaceae, Pinaceae, and Citrae) as agents for dermocosmetic application, based on antimicrobial, antioxidant, and photoprotective activities, and the production of nanocapsules using biodegradable polymer. For this purpose, quantitative extraction of phenolic compounds restricted to legumes (Fabaceae), the aglycone isoflavones daidzein, glycitein, and genistein was performed. The identification and quantification of active compounds were obtained through UHPLC-ESI-QTOF-MS, HPLC-UV/DAD, and GC-MS. Finally, the samples were nanoencapsulated using polycaprolactone. The colloidal suspension obtained was characterized based on zeta potential, pH, particle diameter, and encapsulation efficiency, as well as the efficiency of the spray-drying process. The soy extract prepared using an EtOH:DMSO 80% solution with ultrasound assistance proved to be more efficient in extracting daidzein, glycitein, and genistein (58.0 ± 4.33; 7.37 ± 0.575; 61.9 ± 4.06 mg/100 g respectively) with better photoprotective activity (MEC = 0.482 ± 0.018 mg/mL) and antioxidant activity (9.2 mg GAE/100g; IC50= 1.36 mg/mL). Daidzein and genistein standards showed better photoprotective activity compared to the benzophenone control. Geranium essential oil (Pelargonium graveolens) stood out as an antimicrobial agent (IC50= 5.63 µL/mL; SI=1.68), cedar essential oil (Cedrus atlantica) as a photoprotective agent (MEC = 6.6 µg/mL), and tangerine oil (Citrus reticulata) as an antioxidant (30.9 mg GAE/g). The major components were identified as citronellol for geranium oil, himachalene for cedar oil, and limonene for tangerine oil. The prepared nanocarriers had an average particle diameter of 300 nm, a zeta potential of -20 mV, and IPD between 0.3 and 0.5, demonstrating relative stability regarding the evaluated hydrogenic potential. The encapsulation efficiency was determined in terms of daidzein and genistein isoflavones, with values above 90%, and a drying efficiency of 52%. This work demonstrated the potential of soy isoflavones and essential oils as powerful photoprotective and antimicrobial agents, as well as the feasibility of their incorporation in the form of nanocarriers as potential dermocosmetic agents.
Imunogenicidade de proteínas recombinantes de Erysipelothrix rhusiopathiae: proteção em um modelo murino
(Universidade Federal de São Carlos, 2023-12-08) Godoy, Naiane Lima; Novo-Mansur, Maria Teresa Marques; lattes.cnpq.br/1198926223396748; https://orcid.org/0000-0003-0308-6287; Anibal, Fernanda de Freitas; https://lattes.cnpq.br/4918261968772806; https://orcid.org/0000-0003-0571-8516; https://lattes.cnpq.br/4898786276284560
Erysipelothrix rhusiopathiae is a Gram-positive bacillus that causes swine erysipelas, which leads to the loss and poor development of pigs. Existing vaccines for immunization against erysipelas are made up of killed or attenuated bacteria and, according to reports in the literature, have failed to provide protection, leading to the search for other components that could form a new vaccine against this disease. The surface protein SpaA of E. rhusiopathiae alredy has been reported to induce a host immune response against the bacteria, and hsp70 DnaK has been shown to be an antigenic protein of the bacteria. This work evaluated the immunogenicity and protection induced by the recombinant proteins SpaA and DnaK from E. rhusiopathiae in a murine model. The model was designed in 6 groups of mice that received two doses (subcutaneous and intramuscular) of 40 µg and 100 µg of recombinant proteins. The proteins were evaluated separately and together, compared with a commercial vaccine and with the no-vaccination condition. The proteins were evaluated separately and together, compared with a commercial vaccine and the without vaccination condition. 21 days after the last dose, mice were challenged with a virulent strain of E. rhusiopathiae and serum was collected to assess antibodies, peripheral blood cells were counted, and spleen and kidney tissues were analyzed for the presence of E. rhusiopathiae by colony count. Finally, two survival curves were performed, evaluating the protection induced by the proteins. The results showed that IgG antibodies increased in the serum of animals inoculated with the proteins, which also had bacterial proliferation reduced in the spleens and kidneys evaluated, and presented a significant delay in the symptoms of the disease in this immunization model. These results suggest that the DnaK and SpaA proteins from E. rhusiopathiae have immunogenic potential and can modulate the development of the disease, as assessed in the murine model.
Propriedades farmacológicas da alicina (diallyl thiosulfinate), potencial aplicação em produtos biotecnológicos para suplementação alimentar animal
(Universidade Federal de São Carlos, 2023-12-08) Soares, João Gilberto Bernardi; Moreira, Fernando Manuel Araújo; https://lattes.cnpq.br/1809254923092721; https://lattes.cnpq.br/9077891857660784; https://orcid.org/0000-0002-4155-7345
Babesia Caballi and Theileria Equi are known diseases of parasites of the phylum apicomplexa that share strategies for invasion of red blood cell cells. Pure allicin is a molecule derived from crushed fresh garlic and has antifungal, antiparasitic, and antioxidant properties. In this way, we carried out docking and molecular dynamics experiments in order to verify the pharmacological properties of allicin to be used in the treatment and prevention of T.equi and B. caballi, and to verify its permanence in complex under conditions of temperature, movement, time, pressure and solvated environment, for this, allicin and the proteins PDB Id 3SRI Plasmodium falciparum PfRON2 with 29 aa, PDB Id 4APM AMA1/Babesia Divergens, and the protein constructed by homology model_01Babesia Caballi, Of the amino acid residues that interacted with the active allicin, several belong to the conserved and common sequence among the members of the phylum apicomplexan and have been extensively described in previous works, thus providing important information on the dynamics of the ligand-protein complex. In the molecular docking experiments, interactions with nonpolar amino acid residues predominated, with results of changes in the protein structure according to the spatial arrangement of the functional groups and their insertion rate in the protein cavity, highlighting the importance of noncovalent interactions for the study of drug candidates. The hydrophobicity observed in the protein-ligand interactions showed the tendency of stabilization of the protein structure in the direction of a lower energy gradient about the solvation environment external to the hydrophobic pocket, where the ligand coupling site is. Among the results of the experiments, the RMSD difference from the best adjustment configuration of the allicin ligand characterized its affinity for the amino acid sequence of babesia. The van der Waals energies, which represent the short-range interactions for molecules in a solvated medium, and the long-range electrostatic or Coulomb energies, along with the affinity energy, topology and energetic character of the ligand. With the results of the experiments, it was possible to establish the relationship of the anti-protozoan properties of allicin from the results of the in silico and in vitro experiments, the analysis of the docking results and molecular dynamics of the ligand-protein interactions allowed to point out allicin as a new active potential for the prevention and treatment of Babesia Caballi and Theileria Equi. Which offers conditions for the manufacture of a new product in biotechnology, with the respective patent registration, to be integrated into the diet of horses.