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Plasticidade morfológica em microalgas induzida por predação por Chironomus cf. xanthus Hempel,1939 (Insecta: Chironomidae)
(Universidade Federal de São Carlos, 2021-11-09) Fernandes, Suzana Luisa Alves; Fusari, Lívia Maria; https://lattes.cnpq.br/4951378712238107; Bagatini, Inessa Lacativa; https://lattes.cnpq.br/3904631503604006; https://lattes.cnpq.br/4214494765998822
Microalgae and cyanobacteria are photosynthetic microorganisms with different morphologies and may present phenotypic plasticity under predation risk. They are primary producers in aquatic environments and can be predated by innumerous heterotrophic groups, including benthic invertebrates. Among important benthic invertebrates which feed on microalgae, especially green microalgae, diatoms and cyanobacteria, there is the genus of insects Chironomus (Chironomidae, Diptera). Although the morphological variation of microalgae to avoid predation by planktonic invertebrates has been well documented, little is known about the phenotypic plasticity in microalgae predated by those larvae. In this project, we evaluated the morphological plasticity in microalgae as a defense to predation by Chironomus cf. xanthus larvae. We evaluated the morphological alterations in three microalgae strains of the species: Desmodesmus spinosus, since this genus usually presents phenotypic plasticity under predation by other invertebrates; and two microalgae belonging to genera found in benthos, habitat of the larvae: Micrasterias cf. pinnatifida, a green alga (desmid) and Cyclotella sp. a centric diatom. D. spinosus was evaluated directly over predation, however, due to methodological issues, the other algae were evaluated under the extracellular substances released by the larvae. The experiments were performed in triplicates. Under predation, D. spinosus presented significant increase in the coenobium dimensions on the second day, and in the maximum linear dimension (between spines) at the fourth day of growth; in this same period, a higher number of unicellular individuals was observed. Micrasterias biomass and chlorophyll a concentration (determined by cell count and absorbance) increased significantly on the second day in indirect contact with chironomids. In Cyclotella, extracellular substances released by the chironomid larvae (indirect contact), significantly increased the maximum linear dimensions of the individuals after 2 days, the number of filamentous individuals on the fourth day; and the chlorophyll a concentration from the first to the third days of growth. This is the first work showing morphological plasticity in algae predated by chironomids. The knowledge on the morphological plasticity of microalgae under predation can help elucidate the complex taxonomy of these microorganisms. Furthermore, it can help future studies about the interaction between the larva and its prey and its effects on the biota and local productivity.
Avaliação do estado de superfície obtido no fresamento de ligas de titânio com ferramentas comerciais
(Universidade Federal de São Carlos, 2021-11-09) Silva, Gustavo Vinicius Ferreira da; Antonialli, Armando Ítalo Sette; https://lattes.cnpq.br/4367459395417045; https://lattes.cnpq.br/1613123454650425
The fulfilment of physiological performance criteria that lead to the proper structural and functional connection between bone and implant, called osteointegration, is closely related to the surface characteristics of the biomaterial, which depend on the processes involved in its manufacture. Therefore, the present work aims to expand the understanding about the influence of machining conditions on the surface integrity of commercially pure grade 4 titanium and Ti-6Al-4V ELI components submitted to the milling operation. For this purpose, based on a 2^3 complete factorial design, was selected as influencing factors the type of tool: high-performance cutter and conventional cutter, machined titanium alloy and cutting speed. Three different roughness parameters were used as response variables on the surface state, namely: mean roughness (Ra), asymmetry (Rsk) and flatness (Rku) of the profile. An additional analysis verified the wettability of the machined surfaces through four different ways of measuring the contact angle. The analysis of variance (ANOVA) indicated that the cutting tool corresponds to the main influencing factor of this study, being significant on all response variables. The machined titanium alloy was also influential on the average roughness results, while the cutting speed showed a significant influence on both the average roughness and the asymmetry parameter. Precisely regarding to skewness, it is noteworthy that the different cutters employed produced consistently opposite results, that is: while one tool model resulted in a surface composed predominantly of peaks, the other model resulted in surfaces composed of valleys. Finally, the surface wettability analysis indicated that the milling of Ti-6Al-4V ELI with high performance cutter and high cutting speed results in the surface with higher contact angles among those analysed, characterizing the condition of maximum cell viability within the mean surface roughness limit obtained.
Análise da influência da nanosílica na resistência à compressão de concretos: uma revisão
(Universidade Federal de São Carlos, 2021-11-09) Pedroso, Henrique Thiago Roque; Ferreira, Fernanda Giannotti da Silva; https://lattes.cnpq.br/0329487394818763; https://lattes.cnpq.br/7476694130387544
Currently, concrete is the most used material in civil construction for the most diverse types of constructions. Due to its importance for the area, more researches study about the physical and mechanical properties of the material and seek to improve them. Lately, the use of mineral additions in concretes has intensified in order to improve these characteristics. Among these improvements sought, there is greater durability of the structures. Thus, concomitant with the advancement of nanotechnology use in several areas, the addition of nanosilica in concrete seeks to provide a gain in the compressive strength and durability of the material. The present work had the intention to evaluate the effect of adding nanosilica to concrete, gathering data from scientific works and developing a database, which collected information such as nanosilica percentage and compressive strength values of cementitious materials. Firstly, 39 works were selected, 30 studies on concrete, 6 on cementitious paste and 3 on mortar, due to the higher number, it was chosen to continue with the analysis only for those which worked with concrete. Because of the heterogeneity between the samples and the large number of different nanosilica percentage observed, 24 in total, it was decided to restrict the analysis to 1%, 1.5%, 2%, 3% and 5% of addition of nanosilica for the ages of 7 and 28 days, since they had a larger number of samples. Graphical analyzes were performed using bar graphs, box-plot and linear regression, and Analysis of Variance - ANOVA, Tukey's Test and Anderson-Darling Test for Normality were also used to perform statistical analyses, comparing the values of the compressive strength of the nanosilica traces with the reference. From the results, the conclusion was that there is no significant difference in the compressive strength value of concretes with nanosilica compared to those without addition. However, this result could have been influenced due to the variability of characteristics between samples in the water/binder ratio for instance.
Desenvolvimento de procedimento de produção de kits de instalações elétricas residenciais por meio de BIM
(Universidade Federal de São Carlos, 2021-11-09) Berti, David de Castro; Barreto, Douglas; https://lattes.cnpq.br/7369326190168139; https://lattes.cnpq.br/9699615045398770
The current study aimed to report the process of implementing a workflow for the production of kits for electrical installations within a factory. Focusing on the product development stage, the study also covers other stages such as: project start; factory application and production planning and control, which have direct interaction with the object of this study. The implementation of the BIM methodology contributed to the integration of projects with the factory's control system, reduced the amount of rework and allowed for greater flexibility in the engineering team's work, opening up fronts to absorb more projects
Relação entre apoio social e sono de idosos cuidadores
(Universidade Federal de São Carlos, 2021-11-09) Barbosa, Daniele Cristina; Alves, Élen dos Santos; https://lattes.cnpq.br/9548656064787272; Santos-Orlandi, Ariene Angelini dos; https://lattes.cnpq.br/1334146454214813; https://lattes.cnpq.br/0435715982583886
The lack of social support in old age can intensify health problems, including those related to sleep. In the context of care, both the lack of social support and sleep problems among caregivers can interfere with the quality of care provided and negatively impact the quality of life and well-being of those involved. Therefore, through the early identification of these situations, interventions can be planned in order to reduce expenses with health services and improve the quality of life of these individuals. Objective: to analyze the relationship between social support and sleep of elderly people who care for other elderly people. Method: observational, cross-sectional study, based on the quantitative research method. It was held in a county in the interior of São Paulo. This is an excerpt from a larger study, in which 65 elderly caregivers of other elderly, registered in Family Health Units, participated. The interviews were conducted at the participants' homes between July 2019 and March 2020, by previously trained researchers, using the following instruments: Questionnaire to characterize the elderly caregiver and the context of care; Pittsburgh Sleep Quality Index (PSQI); Medical Outcomes Study Social Support Scale. Differences between groups were estimated using Pearson's chi-squared, Fisher's exact and Mann-Whitney tests. Spearman's correlation test was also used. The level of significance for statistical tests was p-value ≤ 0.05. Results: There was a predominance of elderly female caregivers (56.9%), spouses of the elderly recipient of care (89.3%), with a mean age of 69.1±6.4 years. Regarding social support, it was found that the highest score was obtained in the affective dimension and the lowest score in the positive social interaction dimension. The average number of members of the network of elderly caregivers was 9.7±13.2 people. As for sleep, 50.8% of the elderly caregivers had poor sleep quality. The mean score obtained on the PSQI was 7.4±4.1. There was a weak and inverse correlation between sleep quality and the dimension “positive social interaction” (Rho= -0.27; p=0.028). Furthermore, statistically significant results were identified between: material support and daytime dysfunction (p=0.034); affective support and sleep efficiency (p=0.026); positive social interaction and subjective sleep quality (p=0.001) and daytime dysfunction (p=0.008). Conclusion: The higher the score obtained in the “positive social interaction” dimension, the lower the score on the instrument that assesses sleep quality and vice versa. Overall, positive aspects regarding sleep characteristics are linked to higher social support scores in the present investigation.
Estudos in silico da formação de complexos de alguns fármacos relacionados com a obesidade e potenciais receptores-alvo
(Universidade Federal de São Carlos, 2021-11-09) Borges, Veridiana Guenifer; Gabriel, Jane Eyre; https://lattes.cnpq.br/6757487143317098; https://lattes.cnpq.br/4591075020300046
Obesity is a global health problem in the most diverse geographic locations at all socioeconomic levels that affects several physiological functions and increases the risk of cardiovascular diseases, tumors, musculoskeletal and mental disorders. Some anorectic or appetite-reducing drugs have been administered to promote the reduction of body mass index and to control the obesity. Within this context, a major challenge has been to identify the formation of new complexes ligand-receptor associated with possible positive effects on the improvement of the obese state. Thus, the present study aimed to investigate in silico the formation of complexes of the ligands mazindol, sibutramine and melatonin, drugs related to control and prevention of the obesity, and their potential receptors targeted by molecular docking analyses. The different steps established in this experimental procedure were grouped into three main axes: a) search and selection of 3D structures of the drugs of interest from database DrugBank; b) search and selection of 3D structures of potential protein sequences of receptor-targeted using STRING, protein BLAST, and database PDB; and c) characterization of the formation of the complexes between ligands of interest and receptor-targeted using AutoDock4.0 server by molecular docking analyses. Among all drugs tested in the present study, high reliability score and significant similarity were only identified between type 1B melatonin and alpha-2A adrenergic receptors. Thus, molecular docking assays were carried out using ligand melatonin and crystallographic structures of the alpha-2A adrenergic receptor coupled to an antagonist (ID PDB 6kux) and a partial agonist (ID PDB 6kuy) available in the database PDB. In silico results demonstrated values of binding energy of -6.79 and -6.98 kcal/mol for 6kux and 6kuy adrenergic receptors, respectively. Furthermore, the presence of non-covalent intermolecular interactions, such as hydrogen bonds and hydrophobic interactions, were revealed in the formation of complexes between melatonin and both alpha-2A adrenergic receptors of interest. Preliminary experimental findings described in the literature have revealed a possible interaction of the neurohormone melatonin to adrenergic receptors, indicating its ocular hypotensive effects in rabbits. The findings predicted in the present study suggest the formation of complexes between melatonin and alpha-2A adrenergic receptor by molecular docking analyses, showing satisfactory energy values and structural stability by non-covalent intermolecular interactions. Based on the preliminary data predicted in this study, additional procedures must be established to ensure the experimental validation of the complex melatonin-alpha 2A adrenergic receptor, as well as to test the biological viability of this interaction ligand-receptor of interest and its positive effects on the improvement of the obese state.