Comparative analysis of power electronics topologies to interface dc homes with the electrical ac power grid

This paper presents a comparative analysis of power electronics topologies that can be used to interface dc homes with a 230 V, 50 Hz ac power grid. Dc homes represent an essential asset for smart grids, since energy storage systems and renewable energy sources, such as photovoltaic solar panels, operate in dc, as well as most of the electrical appliances used in domestic scenario. However, since the power grid operates in ac, it is necessary to convert voltage from ac to dc to properly supply a dc home. This conversion can be accomplished in several ways, with different power conversion stages. In this context, this paper analyzes three different possibilities that can be used to perform the interface between the ac power grid and a dc home: (1) ac-dc converter using a low frequency transformer; (2) ac-dc and dc-dc converters using a high frequency transformer; (3) ac-ac and ac-dc converters using a medium frequency transformer. These three possibilities are compared in terms of efficiency, total power factor and total harmonic distortion of the ac power grid. The results were obtained by means of a simulation model based on the internal parameters of the power semiconductors.This work has been supported by FCT –Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2019. This work has been supported by FCT Project DAIPESEV PTDC/EEI-EEE/30382/2017, and by the FCT ProjectnewERA4GRIDs PTDC/EEI-EEE/30283/2017. Mr. Tiago Sousa is supported by the doctoral scholarship SFRH/BD/134353/2017 granted by FCT

Phenotypic characterization of cassava ethno-varieties in the state of Mato Grosso, Brazil.

Brazil is the fourth largest producer of cassava in the world. In the state of Mato Grosso more than 90% of family farmers grow cassava; therefore, studies that evaluate the genetic resources of this species present in the fields of these farmers can be considered essential. The objective of this study was to evaluate the genetic variability among ethnovarieties of cassava grown in five regions of the state of Mato Grosso, at a phenotypic level using morphoagronomic and molecular characteristics. Forty-five ethnovarieties of cassava were evaluated using 45 morphoagronomic descriptors, 36 qualitative descriptors and nine quantitative descriptors, in addition to 15 microsatellite loci. The data were analyzed with the help of the Past and Genes programs. The descriptors of qualitative nature revealed the existence of morphological divergence, with 97.35% polymorphism and the formation of five genetic groups using the UPGMA method. Forty-four ethno-varieties had more than one desirable root characteristic from an agronomic point of view. Among all the varieties, the Amarela I ethno-variety had the most of these characteristics. With the quantitative variables obtained using the UPGMA method, it was possible to form seven distinct groups, which revealed the Branca Comum and Paraguaia ethno-varieties to be the most dissimilar. The characteristic that most contributed to the distinction of the groups was that of root length (30%). The 15 microsatellite loci amplified 109 alleles, and mean heterozygosity observed was higher than the expected heterozygosity. The UPGMA grouping revealed the formation of four distinct groups, and it was possible to verify duplicity of the Mandioca Batatinha and Pramuquem ethnovarities. By using joint analysis of the data, five genetic groups were observed, without duplicity of material; groups III, IV and V were isolated individuals. Between qualitative and quantitative variables, there was a significant correlation of 31% and between qualitative and molecular data the correlation was 12.4%. The collection of ethnovarieties grown in the fields of family farmers in the state of Mato Grosso present genetic divergence at the phenotypic level, based on morphoagronomic and molecular characteristics, and these ethno-varieties have characteristics of interest for genetic improvement and improved marketability

Scaling solutions from interacting fluids

We examine the dynamical implications of an interaction between some of the fluid components of the universe. We consider the combination of three matter components, one of which is a perfect fluid and the other two are interacting. The interaction term generalizes the cases found in scalar field cosmologies with an exponential potential. We find that attracting scaling solutions are obtained in several regions of parameter space, that oscillating behaviour is possible, and that new curvature scaling solutions exist. We also discuss the inflationary behaviour of the solutions and present some of the constraints on the strength of the coupling, namely those arising from nucleosynthesis.Comment: RevTeX, 21 pages, 8 figure

Modelos de negócio e comunicação social: “telcos”, legacy media, novos media e start-ups jornalísticas em navegação digital: estudo prospectivo (2015-2020)

Este não é um estudo “chave na mão” que solucione os problemas do sector da comunicação social portuguesa, do sector em outros países ou à escala global. O estudo é “apenas” um contributo para a identificação de tendências e de metodologias para reduzir a incerteza na gestão de empresas e redacções, procurando oferecer aquilo que, mais à frente, definimos enquanto uma “tecnologia de racionalidade”. É um estudo híbrido quanto à sua forma e conteúdos. Híbrido entre a dimensão de investigação universitária e a prestação de serviços de consultoria, e que não esconde o objectivo, por entender ser na construção dessas pontes que pode produzir mais-valias para o sector da comunicação social em Portugal.info:eu-repo/semantics/publishedVersio

Acute cardiometabolic effects of brief active breaks in sitting for patients with rheumatoid arthritis

Exercise is a treatment in rheumatoid arthritis, but participation in moderate-to-vigorous exercise is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. We compared the acute effects of active breaks in sitting with those of moderate-to-vigorous exercise on cardiometabolic risk markers in patients with rheumatoid arthritis. In a crossover fashion, 15 women with rheumatoid arthritis underwent three 8-h experimental conditions: prolonged sitting (SIT), 30-min bout of moderate-to-vigorous exercise followed by prolonged sitting (EX), and 3-min bouts of light-intensity walking every 30 min of sitting (BR). Postprandial glucose, insulin, c-peptide, triglycerides, cytokines, lipid classes/subclasses (lipidomics), and blood pressure responses were assessed. Muscle biopsies were collected following each session to assess targeted proteins/genes. Glucose [−28% in area under the curve (AUC), P = 0.036], insulin (−28% in AUC, P = 0.016), and c-peptide (−27% in AUC, P = 0.006) postprandial responses were attenuated in BR versus SIT, whereas only c-peptide was lower in EX versus SIT (−20% in AUC, P = 0.002). IL-1β decreased during BR, but increased during EX and SIT (P = 0.027 and P = 0.085, respectively). IL-1ra was increased during EX versus BR (P = 0.002). TNF-α concentrations decreased during BR versus EX (P = 0.022). EX, but not BR, reduced systolic blood pressure (P = 0.013). Lipidomic analysis showed that 7 of 36 lipid classes/subclasses were significantly different between conditions, with greater changes being observed in EX. No differences were observed for protein/gene expression. Brief active breaks in sitting can offset markers of cardiometabolic disturbance, which may be particularly useful for patients who may find it difficult to adhere to exercise. NEW & NOTEWORTHY Exercise is a treatment in rheumatoid arthritis but is challenging for some patients. Light-intensity breaks in sitting could be a promising alternative. Our findings show beneficial, but differential, cardiometabolic effects of active breaks in sitting and exercise in patients with rheumatoid arthritis. Breaks in sitting mainly improved glycemic and inflammatory markers, whereas exercise improved lipidomic and hypotensive responses. Breaks in sitting show promise in offsetting aspects of cardiometabolic disturbance associated with prolonged sitting in rheumatoid arthritis

Synthesis and evaluation of the antifungal activity of 2-(substituted-amino)-4,5-dialkyl-thiophene-3- carbonitrile derivatives

Fifteen 2-[(substituted-benzylidene)-amino]-5-methyl-thiophene-3-carbonitrile (3a-g) and 2-[(substituted-benzylidene)-amino]-4,5-cycloalkyl-thiophene-3-carbonitrile derivatives (4a-h) were synthesized and screened for their in vitro antifungal activity against 42 clinical isolates of Candida (representing 4 different species) and 2 isolates of Criptococcus. The antifungal activities of these compounds were compared to fluconazole and amphotericin B as standard agents. All compounds presented fungicidal activity at different doses, but a few compounds showed moderate or poor antifungal activity when compared with the standard drugs. The Cryptococcus strains were more sensitive than those of the genus Candida, and compound 4d was the most active, with MFC values varying between 100-800 μg/mL. A preliminary SAR study demonstrated that the presence of a cycloalkyl ring linked to the thiophene moiety is essential for antifungal activity, and that the best antifungal candidates are cyclohexyl compounds (4d-f). The results suggest that thiophene derivatives may be interesting compounds for the further development of antifungal drugs.Colegio de Farmacéuticos de la Provincia de Buenos Aire

The cyanobacterial saxitoxin exacerbates neural cell death and brain malformations induced by zika virus

The northeast (NE) region of Brazil commonly goes through drought periods, which favor cyanobacterial blooms, capable of producing neurotoxins with implications for human and animal health. The most severe dry spell in the history of Brazil occurred between 2012 and 2016. Coincidently, the highest incidence of microcephaly associated with the Zika virus (ZIKV) outbreak took place in the NE region of Brazil during the same years. In this work, we tested the hypothesis that saxitoxin (STX), a neurotoxin produced in South America by the freshwater cyanobacteria Raphidiopsis raciborskii, could have contributed to the most severe Congenital Zika Syndrome (CZS) profile described worldwide. Quality surveillance showed higher cyanobacteria amounts and STX occurrence in human drinking water sup-plies of NE compared to other regions of Brazil. Experimentally, we described that STX dou-bled the quantity of ZIKV-induced neural cell death in progenitor areas of human brain organoids, while the chronic ingestion of water contaminated with STX before and during gestation caused brain abnormalities in offspring of ZIKV-infected immunocompetent C57BL/6J mice. Our data indicate that saxitoxin-producing cyanobacteria is overspread in water reservoirs of the NE and might have acted as a co-insult to ZIKV infection in Brazil. These results raise a public health concern regarding the consequences of arbovirus outbreaks happening in areas with droughts and/or frequent freshwater cyanobacterial blooms.Fil: Pedrosa, Carolina da S. G.. D’Or Institute for Research and Education; BrasilFil: Souza, Leticia R. Q.. D’Or Institute for Research and Education; BrasilFil: Gomes, Tiago A.. Universidade Federal do Rio de Janeiro; Brasil. Instituto Oswaldo Cruz; BrasilFil: de Lima, Caroline V. F.. D’Or Institute for Research and Education; BrasilFil: Ledur, Pitia F.. D’Or Institute for Research and Education; BrasilFil: Karmirian, Karina. D’Or Institute for Research and Education; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Barbeito Andrés, Jimena. Universidade Federal do Rio de Janeiro; Brasil. Universidad Nacional Arturo Jauretche. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos; ArgentinaFil: Costa, Marcelo do N.. Universidade Federal do Rio de Janeiro; BrasilFil: Higa, Luiza M.. Universidade Federal do Rio de Janeiro; BrasilFil: Rossi, Átila D.. Universidade Federal do Rio de Janeiro; BrasilFil: Bellio, Maria. Universidade Federal do Rio de Janeiro; BrasilFil: Tanuri, Amilcar. Universidade Federal do Rio de Janeiro; BrasilFil: Prata Barbosa, Arnaldo. D’Or Institute for Research and Education; BrasilFil: Tovar Moll, Fernanda. D’Or Institute for Research and Education; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Garcez, Patricia P.. Universidade Federal do Rio de Janeiro; BrasilFil: Lara, Flavio A.. Instituto Oswaldo Cruz; BrasilFil: Molica, Renato J. R.. Universidad Federal Rural Pernambuco; BrasilFil: Rehen, Stevens K.. D’Or Institute for Research and Education; Brasil. Universidade Federal do Rio de Janeiro; Brasi

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets