72 research outputs found
On the Use of a Hydrogen-Fueled Engine in a Hybrid Electric Vehicle
No full textHybrid electric vehicles are currently one of the most effective ways to increase the efficiency and reduce the pollutant emissions of internal combustion engines. Green hydrogen, produced with renewable energies, is an excellent alternative to fossil fuels in order to drastically reduce engine pollutant emissions. In this work, the author proposes the implementation of a hydrogen-fueled engine in a hybrid vehicle; the investigated hybrid powertrain is the power-split type in which the engine, two electric motor/generators and the drive shaft are coupled together by a planetary gear set; this arrangement allows the engine to operate independently from the wheels and, thus, to exploit the best efficiency operating points. A set of numeric simulations were performed in order to compare the gasoline-fueled engine with the hydrogen-fueled one in terms of the thermal efficiency and total energy consumed during a driving cycle. The simulation results show a mean engine efficiency increase of around 17% when fueled with hydrogen with respect to gasoline and an energy consumption reduction of around 15% in a driving cycle
Dal primo al secondo Sacrificio del Beccari, una favola pastorale a cavallo Della Controriforma
No full textNel Cinquecento la tendenza ad una regolarizzazione in senso classicista, l’adeguamento ai canoni aristotelici, le pressioni della cosiddetta Riforma Cattolica si fanno sempre più intensi e portano alla revisione di moltissime opere. Dopo più di trent’anni della prima publicazione della favola pastorale Sacrificio, anche Agostino Beccari decide realizzare una seconda redazione dell’opera. Le varianti apportate da Beccari nel 1587, quando l’autore aveva Romay presente il modello dell’Aminta del Tasso, hanno evidentemente lo scopo di portare un innalzamento stilistico dell’opera in conformità anche alla tendenza riformistica post Concilio di Trento.In the sixteenth century, the tendency towards regularization in the classical sense, the adjustment to the Aristotelian canon, the pressures of the so-called Catholic Reformation are becoming more intense and lead to revision of many works. More than thirty years after the first publication of his pastoral tale Sacrificio, Agostino Beccari decided to write a second draft of the work. The variations made by Beccari in 1587, when the author had as model Tasso’s Aminta, evidently intended to bring a rise in accordance with the work style trend after the Council of Trent.Nel Cinquecento la tendenza ad una regolarizzazione in senso classicista, l’adeguamento ai canoni aristotelici, le pressioni della cosiddetta Riforma Cattolica si fanno sempre più intensi e portano alla revisione di moltissime opere. Dopo più di trent’anni della prima publicazione della favola pastorale Sacrificio, anche Agostino Beccari decide realizzare una seconda redazione dell’opera. Le varianti apportate da Beccari nel 1587, quando l’autore aveva Romay presente il modello dell’Aminta del Tasso, hanno evidentemente lo scopo di portare un innalzamento stilistico dell’opera in conformità anche alla tendenza riformistica post Concilio di Trento
Localization of new peptidoglycan at poles in Bacillus mycoides, a member of the Bacillus cereus group
No full textBacillus mycoides is a sporogenic Gram-positive soil bacillus of the B. cereus group. This bacillus, which forms hyphal colonies, is composed of cells connected in filaments that make up bundles and turn clock- or counterclockwise depending on the strain. A thick peptidoglycan wall gives the rod cells of these bacilli strength and shape. One approach used to study peptidoglycan neoformation in Gram positives exploits the binding properties of antibiotics such as vancomycin and ramoplanin to nascent peptidoglycan, whose localization in the cell is monitored by means of a fluorescent tag. When we treated B. mycoides strains with BODIPY-vancomycin, we found the expected accumulation of fluorescence at the midcell septa and localization along the cell sidewall in small foci distributed quite uniformly. Intense fluorescence was also observed at the poles of many cells, more clearly visible at the outer edges of the cell chains. The unusual abundance of peptidoglycan intermediates at the cell poles after cell separation suggests that the construction process of this structure is different from that of B. subtilis, in which the free poles are rarely reactive to vancomycin
Las preguntas de un traductor: cartas de Gilberto Beccari a Miguel de Unamuno
No full textThe main focus of this study is the description and analysis of the letters and postcards sent by the Italian translator
Gilberto Beccari to Miguel de Unamuno during their twenty-eight-years long (1908-1935) friendship and trustful
relationship. Their correspondence is significant under many different concerns, such as the questions addressed
to the author in order to solve various technical problems concerning textual, peritextual and extra-textual aspects.
Hence, both the analysis of the documental and literary aspect of the letters, and its description through the filter of
translation studies, are developed.En el presente artículo se describen y analizan las cartas y tarjetas postales que el traductor italiano Gilberto Beccari le remitió a Miguel de Unamuno a lo largo de veintiocho años (de 1908 a 1935) y que atestiguan la amistad y confianza que caracterizó su relación. El interés de este epistolario radica también en las innumerables consultas sobre aspectos textuales, peritextuales y extratextuales de traducción. Este artículo se desarrolla por consiguiente tanto en la vertiente documental-literaria como en la de los estudios descriptivos de traducción
Transcriptional analysis of ftsZ within the dcw cluster in Bacillus mycoides
No full textBackground: In Bacillus mycoides, as well as in other members of the B. cereus group, the tubulin-like protein of the division septum FtsZ is encoded by the distal gene of the cluster division and cell wall (dcw). Along the cluster the genes coding for structural proteins of the division apparatus are intermingled with those coding for enzymes of peptidoglycan biosynthesis, raising the possibility that genes with this different function might be coexpressed. Transcription of ftsZ in two model bacteria had been reported to differ: in B. subtilis, the ftsZ gene was found transcribed as a bigenic mRNA in the AZ operon; in E. coli, the transcripts of ftsZ were monogenic, expressed by specific promoters. Here we analyzed the size and the initiation sites of RNAs transcribed from ftsZ and from other cluster genes in two B. mycoides strains, DX and SIN, characterized by colonies of different chirality and density, to explore the correlation of the different morphotypes with transcription of the dcw genes. Results: In both strains, during vegetative growth, the ftsZ-specific RNAs were composed mainly of ftsZ, ftsA-ftsZ and ftsQ-ftsA-ftsZ transcripts. A low number of RNA molecules included the sequences of the upstream murG and murB genes, which are involved in peptidoglycan synthesis. No cotranscription was detected between ftsZ and the downstream genes of the SpoIIG cluster. The monogenic ftsZ RNA was found in both strains, with the main initiation site located inside the ftsA coding sequence. To confirm the promoter property of the site, a B. mycoides construct carrying the ftsA region in front of the shortened ftsZ gene was inserted into the AmyE locus of B. subtilis 168. The promoter site in the ftsA region was recognized in the heterologous cellular context and expressed as in B. mycoides. Conclusions: The DX and SIN strains of B. mycoides display very similar RNA transcription specificity. The ftsZ messenger RNA can be found either as an independent transcript or expressed together with ftsA and ftsQ and, in low amounts, with genes that are specific to peptidoglycan biosynthesis
Goji berries supplementation improves productive performance of rabbit
No full textThe aim of our study was to evaluate the effects of Goji berries on the productive performance of rabbits. One month before insemination, the New Zealand White does (20 animals/group) were fed a commercial standard diet (group C), supplemented with 1% or 3% Goji (groups 1G and 3G, respectively). After weaning, 50 rabbits/group were randomly selected and fed with the same diet of mothers (C, 1G or 3G) up to 91 days of age. 1G group showed lower pre-weaning mortality (31%, 15%, and 29% for C, 1G and 3G, respectively; P < 0.05), higher litter size (5 ± 1, 7 ± 1, and 6 ± 1 rabbits for C, 1G and 3G, respectively; P < 0.05) and litter weight (1278 ± 72, 1541 ± 61, 1319 ± 61 g for C, 1G and 3G, respectively; P < 0.05) at day 18, and higher litter size at weaning (4 ± 1, 6 ± 1, 4 ± 1 rabbits for C, 1G and 3G, respectively; P = 0.05) than C group. The supplemented groups showed higher body weight at the slaughter (2072 ± 32 g, 2212 ± 28 g and 2313 ± 32 g for C, 1G and 3G, respectively; P < 0.01) than C. Our results show that a supplementation of feed with Goji berries results in an improvement of productive performance in rabbit
Conservação de Butia eriospatha (Martius ex Drude) Beccari (Arecaceae): uma espécie da flora brasileira ameaçada de extinção
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Recursos Genéticos Vegetais.Butia eriospatha (Martius ex Drude) Beccari (Arecaceae) é uma palmeira nativa do Sul do Brasil que está sob grande pressão antrópica. A espécie encontra-se ameaçada de extinção devido à venda ilegal de plantas adultas nos mercados local e internacional, à exploração insustentável de seus frutos, à presença do gado nas áreas de ocorrência e, à degradação e redução de seu hábitat devido aos reflorestamentos com espécies exóticas. Informações sobre os níveis de diversidade genética, bem como o conhecimento da ecologia de B. eriospatha são fundamentais e devem ser utilizadas em planos de conservação. Neste contexto, o objetivo geral deste trabalho foi estabelecer estratégias de conservação a partir de informações genéticas e ecológicas de B. eriospatha. Com base em análises de DNA nuclear, utilizando-se nove marcadores microssatélites, o presente estudo avaliou o sistema reprodutivo, a diversidade e a estrutura genética de oito populações naturais de B. eriospatha (n=920) localizadas no Estado de Santa Catarina. Análise adicional em uma coleção de indivíduos de B. eriospatha (n=50) oriundos de tráfico ilegal, localizados em residências na cidade de Florianópolis/SC, foi realizada com o intuito de comparar os níveis de diversidade genética com os observados nas populações naturais. Além das análises genéticas, aspectos ecológicos como fenologia, demografia, herbivoria e predação foram também analisados em algumas das populações de B. eriospatha. Análises do sistema reprodutivo indicaram que B. eriospatha é uma espécie que se reproduz, preferencialmente, por cruzamentos (t ?m=0,96). A espécie é auto-compatível e a reprodução pode ocorrer por geitonogamia, indicando a capacidade de populações ou mesmo de indivíduos isolados sobreviver e persisitir. Os níveis de diversidade genética foram intermediários e variaram entre as populações de B. eriosptaha (HE=0,40-0,53; HO=0,22-0,51, AR=2,67-3,67). A presença de alelos raros e privativos foram observados na maioria das populações estudadas. A divergência genética entre as populações foi elevada e significativa (FST=0,16-0,25, p<0,005), indicando existirem diferenças genéticas importantes entre as populações ao longo do Estado. A presença de alelos raros e privativos e a diferenciação genética entre as populações de B. eriospatha atestam a necessidade de conservação in situ da variabilidade genética que ainda existe. Quando comparados, os níveis de diversidade genética foram maiores nos indivíduos que foram ilegalmente comercializados (HE=0,62, AR=5,11). A presença de alelos privativos e os índices de diversidade genética observados na coleção de indivíduos em Florianópolis indicam alto potencial para a coleta de sementes e uso de mudas em projetos de restauração e enriquecimento das populações naturais de B. eriospatha. Além disto, baseado em análises Bayesianas, a maior parte dos indivíduos que foram ilegalmente comercializados e plantados em Florianópolis tiveram diferente origens. Em relação a fenologia reprodutiva, a espécie floresce entre outubro e março, frutificando entre novembro e julho. No entanto, a floração e a frutificação foi sazonal entre eventos reprodutivos. As populações de B. eriospatha, exceto uma, apresentaram estrutura demográfica bimodal, constituída por plantas adultas e plântulas. Altas taxas de herbivoria foram registradas, indicando que a estrutura demográfica observada é resultado da ação do gado sobre o componente regenerante. Isto é corroborado pela ocorrência de outros estádios ontogenéticos em uma população onde o gado não está presente. Todos esses resultados, somados ao uso insustentável dos frutos e da alta taxa de predação de sementes, refletem o grau de ameaça em que se encontram as populações de B. eriospatha. Além da relevância de se considerar várias populações em ações de conservação da espécie, mapear e monitorar as populações remanescentes, combater o comércio ilegal e impedir a entrada do gado nas populações de B. eriospatha são ações imprescindíveis para evitar que, de fato, a espécie seja perdida.Butia eriospatha (Martius ex Drude) Beccari (Arecaceae), a palm species native to southern Brazil, is under severe pressure due to anthropogenic factors. The species is threatened with extinction because of the illegal sale of adult plants in local and international markets, unsustainable exploitation of its fruit, livestock grazing in its habitat, and the reduction and degradation of its habitat due to reforestation with exotic species. Information on the genetic diversity levels, as well as ecological knowledge of B. eriospatha, are fundamental and an essential part of conservation planning for this species. Thus, the aim of this study was to establish conservation strategies from genetic and ecological information of B. eriospatha. Based on nuclear DNA analyzes using nine microsatellite markers, the present study evaluates the reproductive system, genetic diversity and structure of eight natural populations of B. eriospatha (n = 920) located in the state of Santa Catarina, Brazil. An additional analysis of a sample of illegally-trafficked B. eriospatha (n = 50) individuals, located in residences of the city of Florianópolis, Santa Catarina, was performed in order to compare levels of genetic diversity with those observed in natural populations. Along with genetic analysis, ecological information, such as phenology, demography, herbivory and predation, were also analyzed in four of the sample populations. Analysis of the reproductive system indicates that B. eriospatha is a species that reproduces primarily through out-crossing (t ?m=0.96). However, the species is self-compatible and reproduction can occur through geitonogamy, indicating the ability of populations, or even isolated individuals, to survive and persist. The levels of genetic diversity found in this study were intermediate and ranged between populations of B. eriosptaha (HE=0.40-0.53; HO=0.22-0.51, AR=2.67-3.67). Rare alleles were observed in most of the studied populations and genetic divergence among populations was high and significant (FST=0.16-0.25, p<0.005), indicating important genetic differences between populations. The presence of rare alleles and genetic differentiation among populations of B. eriospatha attests to the need for in situ conservation of the genetic variability that remains. When compared with the natural populations, the levels of genetic diversity were greater in the individuals that were illegally marketed (HE=0.62, AR=5.11). The presence of rare alleles and high rates of genetic diversity observed in the sample from Florianópolis indicates a high potential for seed collection and the use of seedlings in restoration projects and enrichment of natural populations of B. eriospatha. Moreover, based on Bayesian analysis, the illegally-purchased individuals planted in Florianópolis come from a variety of source populations. Regarding reproductive phenology, the species blooms between October and March, and fruiting occurs from November to July. However, flowering and fruiting were seasonal between observed reproductive events. All the studied natural populations of B. eriospatha, except one, showed a bimodal population structure, consisting of mature plants and seedlings. High rates of herbivory were recorded, indicating that the observed demographic structure is mainly the result of cattle grazing on the regeneration. This conclusion is supported by the occurrence of various ontogenic stages in a population where cattle are not present. Along with the unsustainable use of the fruit and high rates of seed predation, the results discussed herein reflect the level of risk facing B. eriospatha populations. Besides the necessary conservation of the species in a variety of populations, it is important to consider activities that will help prevent the loss of this species, such as mapping and monitoring the remaining populations, combating illegal trade, and preventing cattle grazing in B. eriospatha habitats
Fotografia e scienza in Italia dal 1839 al 1939: il progetto “L’occhio della scienza”
No full text1839 symbolically marks the birth of photography and the beginning of a process that would soon make photography a necessary and unavoidable tool and support for scientific research and practice. Originated from science, photography immediately showed scientists the contribution that it could bring, i.e. the possibility of fixing images, allowing to study objects even in their absence and revealing details invisible to the naked eye. The photographic plate thus became the scientist’s retina and the camera was an essential instrument in observatories, laboratories, trips, hospitals. The project The Eye of Science (L’occhio della scienza), born from the collaboration of the
Museo della Grafica of the University of Pisa with the Museo Galileo of Florence, had the aim of delving into and narrating the birth of scientific photography in Italy, retracing its first century, through some meaningful experiences and personalities. The project yielded two
exhibitions, A Century of Scientific Photography in Italy, 1839-1939 (Un secolo di fotografia scientifica in Italia, 1839-1939) and Giorgio Roster and Odoardo Beccari, Explorers of Places and Images (Giorgio Roster e Odoardo Beccari, esploratori di luoghi e immagini), that illustrate the first applications of photography to the various scientific sectors in Italy, reflecting on its different functions, as well as on potential and limits. Located in the Museum of Graphics of Pisa and in the Stibbert Museum of Florence, the two exhibitions deal with the matter with two different approaches: the first – divided into four sections, Heaven, Earth, Living, Human – focuses on the different scientific disciplines and on the contribution provided by the photographic techniques to them; the second concentrates on two emblematic characters, Odoardo Beccari and Giorgio Roster, illustrating their activity, starting from the birth of the Italian Photographic Society. In parallel with the two “physical” exhibitions, a virtual one was realized, following the lines of the two exhibitions and deepening the topics by means of the collections of the partnering institutions
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