Chemical And Physical Studies Of Charge Transfer Excited States Of Ruthenium Complexes With Aromatic Ligands

The 3MLCT excited states generated from tris-bipyridineruthenium(II), [Ru(bpy)3]2+ and related complexes was ionized by 405 nm irradiation in ambient, acidic aqueous solutions. The photoionization product was Ru(bpy)3]3+ and an electron with a quantum yield of about 0.040.02 in 0.5 M acid. However, 532 nm radiation does not induce photoionization, and it generates the 3MLCT excited state that can be photoionized by 405 nm irradiation. The proton is a very good electron scavenger, and the rate of phoionization of the 3MLCT excited state was determined to be acid dependent and it increased about ten-fold for acid concentrations beween 0.001 and 4 M when 0.1 M isopropanol was used to scavenge hydrogen atoms. Dramatic decreases in [Ru(bpy)3]2+ emission intensities were observed when dual laser irradiations were used for 10-30 min in 0.5 M H+. The minimum free energy required to ionize the [Ru(bpy)3]2+ 3MLCT excited state is about 2 eV (620 nm). Such thermodynamic considerations also indicate that photoionization processes are possible for many of the electron donors whose excited states might be considered for use as photosensitizers. This suggests that the shorter wavelength visible light could lead to their degradation through reactions of the resulting free radicals and other product species when they are used in long term application

Compressed Sensing with off-axis frequency-shifting holography

This work reveals an experimental microscopy acquisition scheme successfully combining Compressed Sensing (CS) and digital holography in off-axis and frequency-shifting conditions. CS is a recent data acquisition theory involving signal reconstruction from randomly undersampled measurements, exploiting the fact that most images present some compact structure and redundancy. We propose a genuine CS-based imaging scheme for sparse gradient images, acquiring a diffraction map of the optical field with holographic microscopy and recovering the signal from as little as 7% of random measurements. We report experimental results demonstrating how CS can lead to an elegant and effective way to reconstruct images, opening the door for new microscopy applications.Comment: vol 35, pp 871-87

In vitro activity of some fluoroquinolones and other unrelated antimicrobial agents against bacterial enteric pathogens

Abstract: The in-vitro activity of ofloxacin, lomefloxacin, ciprifloxacin, fleroxacin, DR-335, and PD-127391 which are all members of the fluoroquinolones and other unrelated (classical) antimicrobials that include, amoxycillin, sulphamethoxazole, trimethoprim, tetracycline and chloramphenicol have been compared against Salmonella typhi, campylobacter jejuni, Yersinia enterocolitica, Vibrio cholerae, Aeromonas hydrophila, and Vibrio parahaemolyticus. Minimum inhibitory concentrations (MICs) of the antimicrobial agents examined were determined. All members of the fluoroquinolones were highly active against all insolates examined and inhibited them at a concentration of <1mg/L. By contrast, many of the isolates examined were resistant to one or more of the classical antimicrobial agents. These results showed a potential clinical role for all the fluoroquinolone compounds tested in the treatment or prophylaxis of bacterial enteric infections where antimicrobial intervention is indicated.[Ethiop. J. Health Dev. 1998;12(2)111:116

Development of Cryostats with Temperature Control for Electrical Characterization of Thin Films in the Range 77-300 K

In this thesis, cryogenic systems capable of measuring thin film electric characteristics at low temperatures (77-300 K) were developed. Building in total three different prototypes capable of precise temperature control using liquid nitrogen as a cold source. Two proto-types measure the AC impedance of the samples and a third one measures the sheet re-sistance. These systems are capable of obtaining the impedance value of DNA and graphene ox-ide thin films and the indium and fluorine doped tin oxides (ITO, FTO) sheet resistance. The study of such samples is essential to future sensor development, opening ways to improve the efficiency of these sensors. In this thesis, we monitor the DNA and graphene oxide thin film impedance values in-crease with temperature decrease. Analyzing the DNA results, it was possible to build an equivalent electric circuit for this thin film, observing the Warburg component of the film. Regarding the ITO and FTO sheet resistance measurements a decrease with temperature was observed.Nesta tese foram desenvolvidos de sistemas criogénicos capazes de fazer uma caracte-rização elétrica de filmes finos a baixas temperaturas (77-300 K). No total três protótipos di-ferente foram construídos, capazes de um controlo preciso da temperatura usando azoto líquido como fonte fria. Dois destes protótipos conseguem obter a impedância da amostra e um terceiro capaz de obter a resistência folha da amostra. Após a construção destes sistemas, estes foram utilizados para medir a impedância de filmes finos de DNA e óxido de grafeno e a resistência-folha de substratos de óxidos de es-tanho dopados com índio e flúor (ITO, FTO). O estudo destes diferentes tipos de amostras é importante para desenvolvimento futuro de sensores, permitindo melhorar a eficácia destes. Nesta tese, observa-se o aumento dos valores de impedância, dos filmes finos de DNA e óxido de grafeno, com a diminuição da temperatura. Observando os resultados obtidos do DNA foi possível fazer a representação de um circuito equivalente, no qual existe uma com-ponente de Warburg no filme de DNA. Quanto às medições de resistência-folha do ITO e do FTO, observa-se uma diminuição destes valores com a temperatura

Initial training of teachers: Comparative study of education systems in Brazil and China

Esta investigación forma parte del ámbito de las políticas educativas sobre la formación inicial del profesorado. La importancia del docente y su formación, como elementos que contribuyen a mejorar la calidad del sistema educativo, avalan la necesidad de analizar las políticas educativas de contextos nacionales y de identificar buenas prácticas en relación a la formación docente. A su vez Brasil y China se erigen como países de gran relevancia con tendencias emergentes en el plano internacional. El objetivo del artículo es detectar convergencias y divergencias entre las propuestas educativas brasileñas y chinas. El análisis está enmarcado en una metodología comparada, donde los primeros apartados presentan las características generales de los dos países y la descripción de sus sistemas de formación del profesorado. Los últimos apartados se adentran en la comparación de ambos países para dar pie a las conclusiones finales, las cuales incluyen propuestas de mejora y aplicaciones de los resultados. Las conclusiones se centran, entre otros, en el nivel de cualificación de los docentes, la distribución curricular de los programas y los mecanismos para mejorar la selección de los docentesThis research belongs to the field of educational policies on the topic of initial teacher education. The significance of teachers and their education, as elements contributing to improve the quality of the educational system, support the need to analyze the policies of national contexts and to identify good practices regarding teacher education. Brazil and China stand as highly relevant countries with emerging trends at the international level. The objective of this article is to detect convergences and divergences between the Brazilian and the Chinese educational proposals. The analysis is framed in a comparative methodology. The first sections present the general characteristics of both countries and the description of their teacher education systems. The next sections delve into the comparison of both countries to finally reach some conclusions, which include suggestions for improvement and application of results. The findings focused, among others, on the level of qualification of teachers, curriculum distribution and mechanisms to improve the selection of teacher

Musculoskeletal Load Exposure Estimation by Non-supervised Annotation of Events on Motion Data

There is a significant number of work pressures that promote the incidence of musculoskeletal disorders in industrial environments. As, unfortunately, many workplace conditions are subject to these biomechanical hazards, this has become an extensively common health disorder. To properly adjust intervention strategies, an ergonomic assessment through surveillance measurements is required. However, most measurements still depend on subjective assessment tools like self-reporting and expert observation. The ideal approach for this scenario would be to use direct measurements that use sensors to retrieve more precise/accurate information of how workers interact with their work environment. Following this approach, one of the major constraints would be that a systematic retrieval of data from a labor environment would require a tiresome process of analysis and manual annotation, deviating resources and requiring data analysts. Hence, this work proposes an unsupervised methodology able to automatically annotate relevant events from direct acquisitions, with the final intent of promoting this type of analysis. The event detection methodology proposes to detect three different event types: 1) work period transition; 2) work cycle transition; and 3) sub-sequence matching by query. To achieve this, the multivariate time series are represented as a Self-Similarity matrix built with the features extracted. This matrix is analysed for each event needed to be searched. The results were successful in the segmentation of Active and Non-active working periods and in the detection of points of transition between repetitive human motions, i.e. work cycles. A method of search-by-example is also presented, being that it allows for the user to detect specific motions of interest. Although this method could still be further optimized in future work, this approach has a very promising prospect as it proposes a strategy of similarity analysis that has not yet been deeply explored in the context of ergonomic acquisition. These advances are also significant given that the summarization of ergonomic data is still a subject in expansion.Num contexto industrial, são várias as tensões que promovem a incidência de distúrbios musculosqueléticos. Uma vez que a maioria das condições laborais estão sujeitas a estas propensões do foro biomecânico, os distúrbiosmusculosqueléticos tornaram-se patologias amplamente diagnosticadas na população ativa. Para desenhar estratégias de intervenção eficientes, é necessário proceder a uma avaliação ergonómica baseada em metododologias de vigilância. Não obstante o reconhecimento desta necessidade, a maioria das medidas ainda depende de ferramentas subjetivas como a auto-avaliação e a observação externa por parte de especialistas. A abordagem preferencial para esta problemática passaria pela aplicação de medições diretas que recorressem a sensores com vista a extrair informação exata e fidedigna do ambiente laboral. Uma das maiores limitações deste leque de soluções consiste no facto de um sistema de recolha de dados neste ambiente implicar um processo exaustivo de análise e anotação manual, o que consome recursos e requer os serviços de analistas de dados. Assim, este trabalho propõe uma metodologia capaz de anotar automaticamente eventos relevantes provenientes de aquisições diretas, com o objetivo final de promover este tipo de análises mais eficientes. A metodologia de deteção de eventos proposta foca-se em três diferentes tipos de eventos: 1) transições entre tarefas; 2) transições entre ciclos de trabalho; e 3) procura de movimentos-exemplo em amostras segmentadas. Para concretizar este trabalho, realizou-se um estudo de matrizes de auto-semelhança. Os resultados provaram-se, na sua maioria, bem-sucedidos no caso da segmentação de períodos Ativos e Não-ativos e na deteção de momentos de transição entre movimentos repetitivos, isto é, ciclos de trabalho. É ainda apresentado um método de procura-porexemplo que permite ao utilizador detetar movimentos-exemplo do seu interesse. Embora este método possa ainda ser otimizado em trabalhos futuros, reflete uma abordagem promissora uma vez que propõe uma estratégia de análise de similaridade que não foi ainda especialmente explorada no contexto dos estudos ergonómicos. Estes avanços são ainda significantes na perspetiva de que a sumarização de dados ergonómicos é uma linha de investigação ainda em expansão

Defining non-contrast CT markers of the ischaemic penumbra in acute stroke

Background and purpose: Isodense swelling is a known early ischaemic change, and it is most likely to represent penumbra tissue on acute non-contrast computed tomography (NCCT) scan. However, in general, its detection by observers showed very poor interobserver agreement, which has been attributed to a lack of defining criteria that differentiate it from hypodensity. The aim of this study is to assess the reliability of detecting isodense swelling within the first six hours post stroke onset. Methods: A three-stage study was designed to test the effect of defining criteria and training on the reliability of detection of isodense swelling on acute NCCT. NCCT and perfusion computed tomography (PCT) scans of patients with acute stroke of less than six hours’ duration were reviewed retrospectively. A web-based tool was used to present NCCT scans to readers of different backgrounds (expert and trainee stroke neurologists and neuroradiologists), who evaluated the scans independently by the Alberta Stroke Program Early CT Score (ASPECTS). In the pre-training stage, nine readers assessed 19 repeated scans (a total of 40 scans) obtained at different slice thicknesses (0.9 mm and 5 mm) and both with and without clinical information. In the consensus stage, definitions for isodense swelling and hypodensity were extracted from simultaneous analysis of NCCT and PCT scans used in the pre-training stage, and potential definitions were circulated to participants for agreement. In the post-training stage, 11 readers assessed 32 scans (5 mm slice thickness) with clinical data after training using the consensus definitions and reviewing examples. Cerebral blood volume (CBV), cerebral blood flow (CBF) and mean transient time (MTT) in each ASPECTS region on all PCT scans were calculated and compared across the three NCCT appearances (normal, hypodense or isodense swelling, and the fate of each ASPECTS region was determined on follow-up NCCT scans. Results: Training increased detection of isodense swelling from 29.4% to 46.8%; significantly (P = 0.0001) improved interobserver agreement from very poor (k = 0.09) to fair (k = 0.30); and ameliorated the predictive power of isodense swelling for penumbra as classified by ASPECTS regions of interest (ROIs) from [sensitivity 9% (confidence interval (CI): 1.9%–24.3%); likelihood ratios positive and negative, 2.5 (CI: 0.6–10) and 0.95 (CI: 0.84–1.06), respectively] to [sensitivity 41% (CI: 30.3%–52.8%); likelihood ratios positive and negative, 5.5 (CI: 3.3–11) and 0.64 (CI: 0.53–0.77), respectively]. Detection of hypodensity did not change significantly with training. Exclusion of outliers improved interobserver agreement for isodense swelling to moderate (k = 0.50). Experience, speciality and clinical information had no significant effect on agreement; however, 5 mm slices increased interobserver agreement on hypodensity significantly (k = 0.34 to k = 0.46, P = 0.01). Intraobserver agreement on both hypodensity and isodense swelling was almost perfect. Hypodensity had low sensitivity for core (41.6% (CI: 33% - 50.7%)) but good likelihood ratios positive and negative (13.7 (CI: 7.5–24.8) and 0.6 (CI: 0.50–0.70), respectively). Both isodense swelling and hypodensity were highly specific (93.8% and 96.9% for penumbra and core, respectively). CBV was increased significantly in isodense swollen areas compared with hypodense areas (P < 0.05). Only 38.3% of isodense swollen ROIs ended in infarction and absence of recanalisation increased odds of infarction four-fold, whereas 90% of hypodense ROIs infarcted with odds of infarction 11 times greater than those of ROIs with isodense swelling. Conclusion: Penumbral tissue in acute stroke patients appears on NCCT as isodense swollen areas that are distinguishable from hypodense regions’ appearance. The detection of penumbral tissue can be improved significantly by training. Isodense swelling most frequently returns normal, particularly in evident recanalisation, and its prognostic value might differ from that of hypodensity

THE IMPACT OF EXCHANGE RATE, INTEREST RATE AND OIL PRICE FLUCTUATIONS ON STOCK RETURNS OF GCC LISTED COMPANIES

Exchange rate risk, interest rate risk and oil price fluctuations are the most demonstrated risks in the GCC (Gulf Cooperation Council) countries (Arouri and Nguyen, 2010). Research, however, in this area is still underdeveloped. The importance of this study is to contribute to this research gap. This research aims to show how these three risks affect firms' market values by examining 473 listed firms in Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates for the period January 2007 to June 2012. The research further examines the determinants of these risks. The study uses the AR (1) EGARCH-M model. The results indicate that stock returns in GCC countries are influenced by the exchange rate risk, interest rate risk and oil price risk. However, the exposure was highest for exchange rate risk and lowest for interest rate risk. While the effects of these risks were mixed, overall, exchange rate risk and oil price risk showed more positive significance as compared to the interest rate risk that showed more negatively significant effect on firm values. The level of the effect of these risk also differed from country to country. However, firms in United Arab Emirates revealed the highest exposure to all the three risks while those in Saudi Arabia showed the least exposed to the three risks. Oman firms also showed high exposure to exchange rate and interest rate risks. The segregated results overall showed lower exposure of financial firms as compared to non-financial firms. However, the non-financial firms in Bahrain were more exposed to the risks than the financial firms. In Saudi Arabia, the financial firms revealed the least exposure to the risk suggesting effective risk management practices. In addition, foreign operations and firm size had a significant influence on the extent of the firms’ exposure to all the three risks. Leverage also influenced the level of exposure to interest rate risk. Profitability, growth and liquidity did not reveal a significant influence on the level of exposure. Further, increasing the risk does not lead to increased returns in most of the GCC countries. The risk-return parameters were largely negative. However, positive news increases return volatility more than negative news in most countries. Also, the current volatility of most GCC firms’ returns are time varying, are a function or past innovation and past volatility. The volatility of stock returns, which is affected by changes in the risk factors, could demonstrate the non-prioritisation of risk management by firms

Comentário ao artigo "Hacia una teoría jurídica sin género"

Commented paper reference: Miranda, L. V. M; Oyaneder, C. V. Hacia una teoría jurídica sin género: feminismo, autonomía e igualdad relacional. Trans/Form/Ação: revista de filosofia da Unesp, v. 44, n. 1, p. 233-258, 2021.Referência do artigo comentado: Miranda, L. V. M; Oyaneder, C. V. Hacia una teoría jurídica sin género: feminismo, autonomía e igualdad relacional. Trans/Form/Ação: revista de filosofia da Unesp, v. 44, n. 1, p. 233-258, 2021

Valor e sentimento moral na teoria kantiana

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-Graduação em Filosofia.Há muito tempo, os leitores de Kant têm se questionado a respeito do valor que Kant atribuiu à ação por dever, pois parece moralmente repugnante não recomendar ações acompanhadas por algum sentimento ou inclinação para realizar o que se deve realizar. Esse problema já foi abordado por Schiller e atualmente alguns comentadores como Richard Henson, Barbara Herman, Paul Guyer e Marcia Baron tem discutido sobre o valor moral e a sobredeterminação da ação por dever em Kant. Entre os problemas a serem examinados estão: Quais as circunstâncias nas quais podemos dizer que alguém agiu por dever? A presença de incentivos cooperativos como, por exemplo, a simpatia e a compaixão, determinam que essa ação não foi feita por dever? Não deve existir qualquer outro sentimento moral, mas somente o dever na prática da ação moral? Com isso, pretendemos investigar o caráter e a função do valor e do sentimento moral na teoria kantiana, tanto em uma leitura da Fundamentação da Metafísica dos Costumes como na Doutrina das Virtudes e, assim, verificar se é possível a sobredeterminação da ação por dever e se há uma possibilidade de que incentivos como a simpatia possam estar presentes na prática da ação moral, sem invalidar seu valor moral