A power amplifier system for testing of distance relay operating characteristic

This paper describes a power amplifier system for testing of distance relay operating characteristic. This power amplifier is based on two three phase inverters with a neutral wire. The output power currents and voltages are controlled by a sliding mode controller. A developed matlab/simulink digital simulator generates the test signals. This test signals are converted in current and voltage references using a microcontroller to connect the digital simulator to the power converter amplifier. Experimental results from a laboratory prototype are presented and discussed

Selection bias: neighbourhood controls and controls selected from those presenting to a Health Unit in a case control study of efficacy of BCG revaccination.

BACKGROUND: In most case control studies the hardest decision is the choice of the control group, as in the ideal control group the proportion exposed is the same as in the population that produced the cases. METHODS: A comparison of two control groups in a case control study of the efficacy of BCG revaccination. One group was selected from subjects presenting to the heath unit the case attended for routine prevention and care; the second group was selected from the neighbourhood of cases. All Health Units from which controls were selected offered BCG revaccination. Efficacy estimated in a randomized control trial of BCG revaccination was used to establish that the neighbourhood control group was the one that gave unbiased results. RESULTS: The proportion of controls with scars indicating BCG revaccination was higher among the control group selected from Health Unit attenders than among neighbourhood controls. This excess was not removed after control for social variables and history of exposure to tuberculosis, and appears to have resulted from the fact that people attending the Health Unit were more likely to have been revaccinated than neighbourhood controls, although we can not exclude an effect of other unmeasured variables. CONCLUSION: In this study, controls selected from people presenting to a Health Unit overrepresented exposure to BCG revaccination. Had the results from the HU attenders control group been accepted this would have resulted in overestimation of vaccine efficacy. When the exposure of interest is offered in a health facility, selection of controls from attenders at the facility may result in over representation of exposure in controls and selection bias

Occurrence of Volcanogenic Inorganic Mercury in Wild Mice Spinal Cord: Potential Health Implications

Mercury accumulation has been proposed as a toxic factor that causes neurodegenerative diseases. However, the hazardous health effects of gaseous elemental mercury exposure on the spinal cord in volcanic areas have not been reported previously in the literature. To evaluate the presence of volcanogenic inorganic mercury in the spinal cord, a study was carried out in São Miguel island (Azores, Portugal) by comparing the spinal cord of mice exposed chronically to an active volcanic environment (Furnas village) with individuals not exposed (Rabo de Peixe village), through the autometallographic silver enhancement histochemical method. Moreover, a morphometric and quantification analysis of the axons was carried out. Results exhibited mercury deposits at the lumbar level of the spinal cord in the specimens captured at the site with volcanic activity (Furnas village). A decrease in axon calibre and axonal atrophy was also observed in these specimens. Given that these are relevant hallmarks in the neurodegenerative pathologies, our results highlight the importance of the surveillance of the health of populations chronically exposed to active volcanic environments.This research was supported by the University of Alicante VIGROB-186

The Health Hazards of Volcanoes: First Evidence of Neuroinflammation in the Hippocampus of Mice Exposed to Active Volcanic Surroundings

Neuroinflammation is a process related to the onset of neurodegenerative diseases; one of the hallmarks of this process is microglial reactivation and the secretion by these cells of proinflammatory cytokines such as TNFα. Numerous studies report the relationship between neuroinflammatory processes and exposure to anthropogenic air pollutants, but few refer to natural pollutants. Volcanoes are highly inhabited natural sources of environmental pollution that induce changes in the nervous system, such as reactive astrogliosis or the blood-brain barrier breakdown in exposed individuals; however, no neuroinflammatory event has been yet defined. To this purpose, we studied resting microglia, reactive microglia, and TNFα production in the brains of mice chronically exposed to an active volcanic environment on the island of São Miguel (Azores, Portugal). For the first time, we demonstrate a proliferation of microglial cells and an increase in reactive microglia, as well an increase in TNFα secretion, in the central nervous system of individuals exposed to volcanogenic pollutants.This research was supported by the Universidad de Alicante VIGROB-186

Synthesis, antimalarial activity, structure–activity relationship analysis of thieno-[3,2-b]benzothiazine S,S-dioxide analogs

An improved procedure for the synthesis of 3-amino-9-arylsubstituted-thieno[3,2-b]benzothiazine S,S-dioxide 2-decarboxylated is reported. Thieno-[3,2-b]benzothiazine S,S-dioxide derivatives were investigated for their abilities to inhibit β-hematin formation, hemoglobin hydrolysis and in vivo for their efficacy in rodent Plasmodium berghei. Compounds 5j-o were the most promising as inhibitors of hemoglobin hydrolysis, however, the compounds are not as efficient as chloroquine. A structure-activity relationship (SAR) study was carried out in this series. Our results allow us to determine the minimal structural requirements to produce the biological response.Fil: Barazarte, Arthur. Universidad Central de Venezuela; VenezuelaFil: Camacho, José. Universidad Central de Venezuela; VenezuelaFil: Domínguez, José. Universidad Central de Venezuela; VenezuelaFil: Lobo, Gricela. Universidad Central de Venezuela; VenezuelaFil: Gamboa, Neira. Universidad Central de Venezuela; VenezuelaFil: Rodrigues, Juan. Universidad Central de Venezuela; VenezuelaFil: Capparelli, Mario V.. Universidad Central de Venezuela; VenezuelaFil: Álvarez Larena, Ángel. Universitat Autònoma de Barcelona; EspañaFil: Andujar, Sebastian Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Enriz, Ricardo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Charris, Jaime. Universidad Central de Venezuela; Venezuel

Benzothienoquinolines: new one-pot synthesis and fluorescence studies of their interaction with DNA and polynucleotides

Revised version. "Available online 10 August 2014"In this work, we were able to obtain the benzothieno[3,2-b]quinoline 1 and benzothieno[2,3-c]quinoline 2 using a new one-pot procedure from the reaction of the commercially available 3-bromobenzo[b]thiophene-2-carbaldehyde with 2-aminophenylpinacolborane under Suzuki coupling conditions using a stereochemically hindered ligand, 2-(cyclohexylphosphane)biphenyl and Ba(OH)2.8H2O as the base. Fluorescence properties of the benzothieno[3,2-b]quinoline 1 and the benzothieno[2,3-c]quinoline 2 were studied in solvents of different polarity. Both compounds exhibit a solvent sensitive emission, compound 1 being less fluorescent (quantum yield < 0.05) than compound 2 (quantum yield between 0.04 and 0.10). The interaction of these compounds with salmon sperm DNA and synthetic double-stranded heteropolynucleotides, poly(dA–dT)•(dA–dT) and poly(dG–dC)•(dG–dC), was studied using spectroscopic methods, allowing the determination of the intrinsic binding constants and binding site sizes. The interaction of both compounds is stronger with adenine-thymine (A-T) base pairs. Compound 1 is the most intercalative in salmon sperm DNA (47%) and polynucleotides (46%-49% of intercalated molecules), while for compound 2, 41% is intercalated in salmon sperm DNA and only 8% in poly(dG–dC)•(dG–dC). Docking studies indicate that compound 1 interacts more strongly with DNA than compound 2, with a significant value of binding free energy in the case of intercalation. Minor groove binding is also very favorable and, probably, both mechanisms occur with a preponderance of intercalation in the case of compound 1. Overall, these results indicate that both benzothienoquinolines interact with nucleic acids by both intercalation and groove binding.Foundation for the Science and Technology (FCT, Portugal), for financial support to the Portuguese NMR network (PTNMR) and also to FEDER and QREN for financial support to the Research Centres, CFUM [Strategic Project PEst-C/FIS/UI0607/2013 (FCOMP-01-0124-FEDER-037291)] and CQ/UM [Strategic Project PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302)], and to the research project PTDC/QUI-QUI/111060/2009 (F-COMP-01-0124-FEDER-015603) also financed by COMPETE/QREN/EU. FCT, POPH-QREN and FSE are acknowledged for the PhD grants of A.R.O.R. (SFRH/BD/90949/2012) and M.S.D.C. (SFRH/BD/47052/2008), for the Post-Doc. Grant of R.C.C. (SFRH/BPD/68344/2010) and for support to MAP-Fis Doctoral Program

Evaluation of plant extracts as an efficient source of additives for active food packaging

Natural extracts have been used in several traditional medicine applications and culinary purposes. Their biological properties (antioxidant and antimicrobial) are due to the presence of several active aromatic compounds. Herein, different natural extracts were evaluated, namely structural and thermal characterization and biological activity, in its natural form and incorporated into a polymeric matrix, to assess their effective potential as additives for active food packaging. While rosemary presented the highest thermal stability with a degradation starting at 327°C, lemon balm extract was the less stable (180°C). Regarding the thiobarbituric acid assay, all extracts presented antioxidant activity, in oxidative hemolysis inhibition; anise, cinnamon, and clove extract did not present any action. Overall, the results demonstrated that leaves (rosemary and green tea) and the rhizome (curcumin) are the plant parts with the best performance. Therefore, extracts from aromatic plants are promising natural additives that can be incorporated into polymeric matrices to produce active food packaging film, increasing products shelf-life.The authors acknowledge the financial support by Portugal 2020, and Fundo Social Europeu (FSE) through Programa Operacional Regional do NORTE (NORTE-08-5369–FSE-000034), developed under the program “IMPULSE - Polímeros e Compósitos: Drivers da inovação tecnológica e da competitividade industrial”. To the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional scientific employment program-contract for R. Calhelha, C. Pereira, and L. Barros contracts. This work has also been supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-9/2021-14/ 200007).info:eu-repo/semantics/publishedVersio

CLASSE HOSPITALAR: A GESTÃO PEDAGÓGICA DE PROFESSORES COM EDUCANDOS EM IMINÊNCIA DE MORTE

Este artigo objetiva compreender a atuação pedagógica de professores de classes hospitalares com educandos em iminência de morte. Utiliza-se de pesquisa exploratória de natureza qualitativa a partir da análise de entrevistas com professores que atuam ou atuaram nessas circunstâncias. Buscou-se referendar as principais políticas públicas que asseguram o atendimento educacional ao educando em tratamento de saúde. Os resultados do estudo sinalizam que lidar com alunos em iminência de morte é um desafio constante, entretanto, isso não impõe limite à prática do professor que respeita e entende a mediação da aprendizagem como uma forma de enfrentamento e de ressignificação da realidade

Qualidade fisiológica e sanitária de sementes de milho pré-condicionadas em água ozonizada

A técnica de hidratação controlada das sementes vem sendo utilizada como método de condicionamento fisiológico, objetivando melhorar o seu desempenho no campo. A aeração da solução com gás ozônio constitui opção promissora no controle de fitopatógenos. O objetivo do presente trabalho foi estudar a qualidade fisiológica e sanitária de sementes de milho pré-condicionada em água ozonizada. Na avaliação da qualidade fisiológica e sanitária, as sementes de milho foram submetidas a quatro concentrações de gás ozônio (0, 10, 20 e 30 mg L-1) em cinco períodos de embebição (0, 30, 60, 90 e 120 min), com quatro repetições. A técnica de pré-condicionamento das sementes de milho em água ozonizada, seguida de secagem natural, acarretou desenvolvimento inicial mais acentuado das plântulas de milho, avaliado por meio do índice de velocidade de emergência, matéria seca de plântulas, comprimento de plântula e radícula, quando comparadas com as sementes não tratadas. O desenvolvimento inicial das plântulas de milho foi intensificado mediante exposição das sementes à água, especialmente nas concentrações de 0 e 30 mg L-1 de ozônio, durante o período de 60 a 90 min. O pré-condicionamento das sementes de milho em água ozonizada não afetou o controle de Fusarium sp. O fungicida carbendazim+thiram resultou em 100% de controle de Fusarium sp. nas sementes.The technique of controlled hydration of seeds has been used as a method of physiological conditioning to improve their performance in the field. Solution aeration with ozone gas is a promising option in controlling phytopathogens. The objective of the present study was to evaluate the physiological and sanitary quality of maize seeds preconditioned in ozonated water. In the evaluation of the physiological and sanitary quality, maize seeds were submitted to four concentrations of ozone gas (0, 10, 20 and 30 mg L-1) for five soaking periods (0, 30, 60, 90 and 120 min), with four replicates. Preconditioning maize seeds in ozonated water, followed by natural drying, resulted in a more pronounced initial development of seedlings, measured by means of the emergence speed index, seedling dry matter, seedling length and radicle length, compared with untreated seeds. The initial development of maize seedlings was intensified by the exposure of seeds to water, especially at 0 and 30 mg L-1 ozone concentrations during the period from 60 to 90 min. Preconditioning maize seeds in ozonated water did not affect the control of Fusarium sp. The fungicide Carbendazim + Thiram resulted in 100% control of Fusarium sp. in the seeds

A evolução da ocupação do espaço marinho do litoral catarinense pela malacocultura (1995-2005)

A análise da evolução do processo de expansão dos cultivos de moluscos bivalves marinhos (malacocultura) apontou problemas de natureza diversa, dentre os quais se destacam o espacial e o ambiental, caracterizando a falta de efetivo planejamento para permitir que a atividade se desenvolva de forma adequada. Este trabalho procurou demonstrar como isto ocorreu no litoral catarinense no período entre 1995 e 2005, bem como algumas abordagens sobre as equivocadas estratégias adotadas para a ocupação do espaço marinho-costeiro catarinense e possíveis consequências destas práticas. Este estudo torna-se relevante, por avaliar aspectos relacionados à conservação da Zona Costeira, inserida na Constituição Federal Brasileira como Patrimônio Nacional, bem como pela dimensão que apresenta a malacocultura em Santa Catarina, principalmente se for considerado seu processo de expansão. Dados referentes a um Projeto de Planejamento para a atividade de 1995, de um posterior Termo de Ajustamento de Conduta (TAC) entre os maricultores e o IBAMA, de 2003, e vistorias de campo nas áreas aquícolas do Estado, em 2005, foram comparados, fornecendo as informações geradas por este estudo. Em 2005, cerca de 506 ha do espaço marinho catarinense encontravam-se efetivamente utilizados pela atividade.