O papel da desordem local e da interferência quântica na localização de estados eletrônicos

Orientador: Guillermo Gerardo Cabrera OyarzunTese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb WataghinResumo: Desenvolvemos um novo método para o cálculo da Densidade de Estados eletrônicos (DOS) de Ligas Binárias Desordenadas. O método proposto permite a introdução de efeitos de ordem de curto alcance (SRO) e da presença de campo magnético. A estrutura da DOS é utilizada para analisar efeitos de localização dos estados eletrônicos. Nossos resultados mostram que os efeitos de SRO têm um papel essencial na localização dos estados eletrônicos. Obtivemos evidências da presença de estados eletrônicos não exponencialmente localizados para o caso bidimensional. O campo magnético aplicado induz mudanças na DOS que mostra um comportamento oscilatório de deslocalização-localização, quando o sistema está próximo do regime de localização fracaAbstract: We have developed a new method to calculate the electronic Density of States (DOS) of disordered binary alloys. The method proposed permits to introduce effects of Short Range Order (SRO) and of an applied magnetic field. The structure of the DOS is used to analyse localization effects of the electronic states. We found that SRO effects plays an essential role in the localization of the electronic states. We obtained evidences of the presence of non-exponentially localized electronic states for the two-dimensional case. The applied magnetic field induces changes in the DOS which shows an oscillatory behaviour of delocalization-localization, when the system approaches to the weak localization regimeDoutoradoFísicaDoutor em Ciência

Association of organized physical activity and levels of cardiorespiratory fitness with indicators of mental health in children

To verify the associations between organized physical activity out of school (PA) and cardiorespiratory fitness (CRF) with indicators of mental health in children. Methods: This is a cross-sectional study, with a sample of 226 students (47% girls) of public school in the south of Brazil aged between 6 to 11 years-old (8.36 ± 1.46). The cardiorespiratory fitness was measured by running and walking-test in six minutes, following the procedures of the “Brazil Sports Project”. PA was evaluated through a question and the Strengths and Difficulties Questionnaire assessed mental health indicators. Generalized linear regressions were used with a confidence interval of 95%. Results: Total difficulties (β = 2.691; 95%CI, 0.181 to 5.200) and emotional symptoms (β = 1.528; 95%CI, 0.609 to 2.448) were inversely associated with PA. Total difficulties (β = -0.013; 95%CI, -0.022 to -0.003), hyperactivity/attention deficit (β = -0.002; 95%CI, -0.010 to -0.002), and peer relationship problems (β = -0.002; 95%CI, -0.003 to -0.001) were associated with CRF in boys. Conclusion: A total of difficulties and emotional problems presented an inverse association with PA. Further, CRF was inversely associated with total difficulties, hyperactivity-inattention, and peer relationship problems

Challenges and opportunities of buddhism in Brazil : report of a symposium with buddhist translators/academics

A partir de um Simpósio Virtual ocorrido em agosto de 2020 com praticantes e estudiosos do budismo, alguns deles tradutores budistas de diversas línguas (chinês, japonês, tibetano e sânscrito) para o português, emergem várias questões. A motivação deste encontro foi a de dialogar sobre importantes questões sobre o budismo no presente momento que vivemos, suas oportunidades e desafios. Ao longo do debate fica evidente o grande hiato cultural entre o Brasil e os países asiáticos. Igualmente se revela a sofisticação e rigor necessários às traduções bem como a necessidade e a dificuldade de estabelecer esse debate na academia. Este artigo apresenta os pontos mais importantes de cada exposição, os coloca em perspectiva e encaminha considerações finais sobre os desafios e oportunidades presentes no amplo tema das traduções e do diálogo acadêmico com o budismo.Several questions emerged from a Virtual Symposium that took place in August 2020 with practitioners and scholars of Buddhism, some of them Buddhist translators from different languages (Chinese, Japanese, Tibetan and Sanskrit) into Portuguese. The motivation of this meeting was to discuss important questions about Buddhism in our day and age, its opportunities and challenges. Throughout the debate it became evident that there is a great cultural gap between Brazil and Asian countries. It also reveals the sophistication and rigor required for translations, as well as the need and difficulty of establishing this debate in academia. This article presents the most important points of each speech, puts them in perspective and makes final considerations about the challenges and opportunities present in the broad topic of translations and academic dialogue with Buddhism

DESAFIOS E OPORTUNIDADES DO BUDISMO NO BRASIL: RELATO DE UM SIMPÓSIO COM TRADUTORES/ACADÊMICOS BUDISTAS

A partir de um Simpósio Virtual ocorrido em agosto de 2020 com praticantes e estudiosos do budismo, alguns deles tradutores budistas de diversas línguas (chinês, japonês, tibetano e sânscrito) para o português, emergem várias questões. A motivação deste encontro foi a de dialogar sobre importantes questões sobre o budismo no presente momento atual, suas oportunidades e desafios. Ao longo do debate fica evidente o grande hiato cultural entre o Brasil e os países asiáticos. Igualmente se revela a sofisticação e rigor necessários às traduções bem como a necessidade e a dificuldade de estabelecer esse debate na academia. Este artigo apresenta os pontos mais importantes de cada exposição, os coloca em perspectiva e encaminha considerações finais sobre os desafios e oportunidades presentes no amplo tema das traduções e do diálogo acadêmico com o budismo

Nanoemulsão aquosa, processo de produção de nanoemulsão aquosa e método de controle de pragas

DepositadaApresenta uma nanoemulsão com atividade bioinseticida, permite a incorporação de substâncias insolúveis em meio aquoso, através de uma formulação estável, fina e elegante. A possibilidade de solubilizar substâncias apolares em meio aquoso permite que a formulação seja utilizada na liberação de substâncias insolúveis bioativas, com potencial ação inseticida frente a pragas agrícolas e/ou aplicação em focos de proliferação de larvas de Aedes aegypti, importante vetor da dengue. Ainda, a presente invenção apresenta processo de produção de nanoemulsão aquosa e método de controle de pragas por nanoemulsão aquosa

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Studies of the mass composition of cosmic rays and proton-proton interaction cross-sections at ultra-high energies with the Pierre Auger Observatory

In this work, we present an estimate of the cosmic-ray mass composition from the distributions of the depth of the shower maximum (Xmax) measured by the fluorescence detector of the Pierre Auger Observatory. We discuss the sensitivity of the mass composition measurements to the uncertainties in the properties of the hadronic interactions, particularly in the predictions of the particle interaction cross-sections. For this purpose, we adjust the fractions of cosmic-ray mass groups to fit the data with Xmax distributions from air shower simulations. We modify the proton-proton cross-sections at ultra-high energies, and the corresponding air shower simulations with rescaled nucleus-air cross-sections are obtained via Glauber theory. We compare the energy-dependent composition of ultra-high-energy cosmic rays obtained for the different extrapolations of the proton-proton cross-sections from low-energy accelerator data

Study of downward Terrestrial Gamma-ray Flashes with the surface detector of the Pierre Auger Observatory

The surface detector (SD) of the Pierre Auger Observatory, consisting of 1660 water-Cherenkov detectors (WCDs), covers 3000 km2 in the Argentinian pampa. Thanks to the high efficiency of WCDs in detecting gamma rays, it represents a unique instrument for studying downward Terrestrial Gamma-ray Flashes (TGFs) over a large area. Peculiar events, likely related to downward TGFs, were detected at the Auger Observatory. Their experimental signature and time evolution are very different from those of a shower produced by an ultrahigh-energy cosmic ray. They happen in coincidence with low thunderclouds and lightning, and their large deposited energy at the ground is compatible with that of a standard downward TGF with the source a few kilometers above the ground. A new trigger algorithm to increase the TGF-like event statistics was installed in the whole array. The study of the performance of the new trigger system during the lightning season is ongoing and will provide a handle to develop improved algorithms to implement in the Auger upgraded electronic boards. The available data sample, even if small, can give important clues about the TGF production models, in particular, the shape of WCD signals. Moreover, the SD allows us to observe more than one point in the TGF beam, providing information on the emission angle