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Electromagnetically induced transparency under effects of light-mediated interactions, entanglement generation, and Fock states detection
(Universidade Federal de São Carlos, 2022-10-25) Oliveira, Murilo Henrique de; Villas-Bôas, Celso Jorge; https://lattes.cnpq.br/5700887540085418; https://lattes.cnpq.br/7635532484317309
This thesis presents a brief compilation of the works developed during my doctorate, and can be divided basically into three main parts. In the first one, we show the changes caused by considering long-range interactions mediated by light in the phenomenon of electromagnetically induced transparency (EIT). We also show how these interactions can negatively impact population transfer through a stimulated Raman adiabatic passage (STIRAP) process, which may imply a technical limitation for EIT-based quantum memories, as the density and optical thickness of the samples have been increasing in recent experiments to obtain better efficiencies. In the second part, we propose two new schemes to generate highly entangled states in a system of two non-degenerate qubits coupled to a common bosonic mode, in both of which we use an EIT analogue to better understand and interpret the physics of the system. The first method relies on the injection of energy into the mode through a coherent pump to prevent the mode from decaying to vacuum, and under a certain parameter regime, we show that it is possible to obtain a maximally entangled steady state. In the second method, we transfer the population to the maximally entangled state through a STIRAP-like process. In the third and last part, we present a new idea for single-shot measurements of Fock states using the Autler-Townes effect, where two methods are proposed: both a destructive and a non-destructive one. The results presented were obtained from the experimental implementation of this scheme in a system of trapped ions, for measurements of phonon number states.
Análise toxicológica da nanopartícula de óxido de ferro misto (NP Fe3O4) com ligantes de sulfonato de sódio (SO3)-Na+): in vitro e in vivo
(Universidade Federal de São Carlos, 2022-10-25) Feitosa, Karina Alves; Anibal, Fernanda de Freitas; https://lattes.cnpq.br/4918261968772806; https://lattes.cnpq.br/1711011967064666
Known for their biocompatible potential and magnetic property, iron oxide nanoparticles are the target of several studies for different applications. However, the synthesis of new nanoparticles with different physicochemical characteristics leads to unknown biological interactions that may pose health risks to their manipulators. In this study, the mixed iron oxide nanoparticle (Fe3O4 NP) with sodium (SO3)-Na+) sulfonate ligands, of interest in the energy sector, was evaluated through nanotoxicological aspects. Initially, morphological, chemical, and physical characterization of the Fe3O4 NP was performed using SEM-FEG (High-Resolution Scanning Electron Microscopy), DLS (Dynamic Light Scattering), Zeta Potential, UV-Vis (Ultraviolet-Visible Absorption Spectroscopy) and ATR-FTIR (Fourier Transform Attenuated Total Reflection Infrared Spectroscopy) techniques. For the in vitro experiments, different concentrations of Fe3O4 NP (250; 100 and 50 μg/mL) were analyzed against murine fibroblasts (LA-9) in periods of 24, 48 and 72h. Thus, its cytotoxic potential was established through analysis of mitochondrial function (MTT), morphological changes and cell internalization (Prussian Blue), production of Reactive Oxygen Species (ROS), Nitric Oxide (NO) (Griess reaction), cytokines (IL-6 and TNF), determination of cell death (flow cytometry) and analysis of clonogenic potential on the 7th day after exposure. For the in vivo experiments, mice (BALB/c) were divided into 5 experimental groups (100; 50; 25 and 10 mg/Kg of Fe3O4 NP) and were intraperitoneally exposed to 4 doses over 14 days, and the toxicity of repeated doses was evaluated. Indicative signs of toxicity, hematological parameters (overall and differential leukocyte count), liver function analyses (TGO and TGP), quantification of cytokines (IFN-ˠ; TNF; IL-6 and IL-10) and histological analysis of the organs, heart, lung, liver, spleen and kidneys were evaluated. The results showed that Fe3O4 NP has a circular shape, with heterogeneous particle distribution, compacted and agglomerate formation. There was the internalization of Fe3O4 NP for all concentrations tested in vitro (250, 50 and 100 μg/mL) in a time/dependent manner. However, the increase in ROS occurred only for the 250 μg/mL concentration. Moreover, it is suggested that this same concentration triggered a senescence process in fibroblasts (LA-9), due to the low cellular metabolism and consequent reduction in colony formation within seven days. All concentrations tested during in vivo experimentation (100; 50; 25 and 10 mg/Kg) promoted damage to mouse organs, especially to the liver. There was activation of the immune system through the production of leukocytes and pro-inflammatory cytokines. Our results contribute to the knowledge about the toxicology of iron oxide nanoparticles, demonstrating the importance of analyses in longer periods after exposure. Keywords: Nanotoxicology; Inflammation; BALB/c; LA-9; Histology; Senescence.
O teletrabalho docente na cultura digital e o direito à desconexão
(Universidade Federal de São Carlos, 2022-10-25) Oliveira, Ricardo Nascimento de; Mill, Daniel Ribeiro Silva; https://lattes.cnpq.br/1515286597269486; https://lattes.cnpq.br/7117414340148663
This research aims to investigate the consequences of teaching telework in the context of digital culture in the light of changes in the Brazilian labor legislation. The intensive use of digital technologies and mobile telecommunication devices has changed life in society, with repercussions on work. This transformation particularly affected the working hours, form and place of work of professors who carry out non-face-to-face activities. Based on a bibliographical survey, on Brazilian legislation, on the Labor Code of Portugal, on Comparative Law and International Human Rights Law standards, the general objective is to analyze, in the context of teaching telework made possible by digital technologies, how are the boundaries between the teacher's professional and personal life. In pursuit of this general objective, five specific objectives were considered: to draw an overview of the transformations in the working hours of teaching teleworkers in the graphocentric digital society of the 21st century; to analyze the factual and legal contours of the phenomenon of invasion of the privacy of teaching teleworkers through work, through TDIC, as well as to observe how their periods of non-work are going (especially in the midst of the Covid-19 pandemic); to analyze the repercussions of the teaching telework situation regarding the load of professional activities and the right to disconnect; to map the rights and duties of teachers, in a situation of telework, within the graphocentric digital society, with regard to the folding of time and space (ubiquity) and the working day (flexibilization, precariousness); draw a comparative profile of the regulation of teaching telework in Brazilian legislation, post-labor reform (Law 13,467, of July 13, 2017), with the Portuguese one (Labor Code), making incursions in Comparative Law and International Human Rights Law, aiming to investigate the improvements that can be made in the national legislation. With regard to methodology, a general literature review was carried out, field research was carried out, using a questionnaire (with objective and open questions) and semi-structured interviews with the participating professors, analyzing the data qualitatively and quantitatively. Documentary analysis of normative texts of International Human Rights Law was also produced, as well as comparative law, covering Brazilian, Portuguese, French, Argentinean, Chilean law. Due to telework and ubiquity, precarious rights are observed, as opposed to promises and real benefits. As a result of the work, it is recommended the inclusion of the right to disconnection in the country's legislation, the implementation of public policies to raise class awareness in favor of better working conditions for teachers, as well as the establishment of equal rights, especially in regarding the workday, between face-to-face workers and teaching teleworkers.
Ensino de autocuidados para docentes em tempos de pandemia da Covid-19
(Universidade Federal de São Carlos, 2022-10-25) Soares, Caroline Fernanda; Carmo, João dos Santos; https://lattes.cnpq.br/1263046410329694; https://lattes.cnpq.br/9068652218632978
This study verified the effects of online self-care intervention on the well-being of elementary school teachers during the COVID-19 pandemic. In the pre-test, the Lipp Stress Symptoms Inventory for Adults (ISSL), the Beck Anxiety Inventory (BAI) and the WHO quality of life instrument (WHOQOL-bref) were applied. The intervention consisted of a stress management workshop, with relaxation techniques and daily self-care. Post-test and follow-up involved reapplying the pre-test, immediately after the intervention and three months later, respectively. The group and individual results pointed to a reduction in stress and anxiety levels, expressing the importance of intervention studies that aim at the well-being of the teaching category, exploring various techniques and methods, and that consider the effects that the COVID-19 pandemic may have caused in the short, medium and long term.