Fuel cell and hydrogen storage development for a wheel chair

In this paper are presented, the recent advances of a demonstration project that focuses on the implementation of a hybrid system for a wheel chair incorporating a fuel cell and a metal hydride hydrogen storage system. Advantages regarding weight reduction and greater autonomy are emphasized, apart from the use of clean energy and the drastic reduction in charging time, when compared with the system before conversion

Propriedades Desejáveis a uma Linguagem de Programação: Uma Análise Comparativa entre as Linguagens C, C++ e Java

A forma de pensar em soluções para determinados problemas aumenta consideravelmente ao se estudar comparativamente mais de uma linguagem de programação(LP). Este trabalho visa comparar as LP’s C, C++ e JAVA analisando as propriedades desejáveis. A linguagem JAVA destacou-se nos critérios de confiabilidade,portabilidade e reusabilidade e legibilidade. O C ++ apresentou-se ser a linguagem com maior dificuldade de aprendizado, porém observou-se um excelente desempenhonos critérios de reusabilidade e legibilidade. O C mostrou-se em relação às demais LP ser a linguagem com maior deficiência nos critérios de portabilidade, reusabilidade e lêgibilidade ao possuir características facilmente usadas para se criar código ilegível e de difícil manutenção. Por fim, o estudo proporcionou a aquisição de novos conhecimentose uma maior compreensão em relação ao estudo dos paradigmas de programação

Bioaccumulation of amylose-like glycans by Helicobacter pylori

Background: Helicobacter pylori cell surface is composed of lipopolysaccharides (LPSs) yielding structures homologous to mammalian Lewis O-chains blood group antigens. These structures are key mediators in the definition of host-microbial interactions and known to change their expression pattern in response to environmental pressure. Aims:  The present work is focused on the identification of new H. pylori cell-surface glycosides. Special attention is further devoted to provide insights on the impact of in vitro subcultivation on H. pylori cell-surface phenotypes. Methods:  Cell-surface glycans from H. pylori NCTC 11637 and two clinical isolates were recovered from the aqueous phase resulting from phenol:water extraction of intact bacteria. They were evaluated in relation to their sugars and glycosidic-linkages composition by CG-MS, size-exclusion chromatography, NMR, and Mass Spectrometry. H. pylori glycan profile was also monitored during subcultivation in vitro in agar and F12 liquid medium. Results:  All three studied strains produce LPS expressing Lewis epitopes and express bioaccumulate amylose-like glycans. Bioaccumulation of amylose was found to be enhanced with the subcultivation of the bacterium on agar medium and accompanied by a decrease in the expression of LPS O-chains. In contrast, during exponential growth in F12 liquid medium, an opposite behavior is observed, that is, there is an increase in the overall amount of LPS and decrease in amylose content. Conclusions:  This work shows that under specific environmental conditions, H. pylori expresses a phase-variable cell-surface α-(1→4)-glucose moiety

A Transcriptomic View of the Proteome Variability of Newborn and Adult Bothrops jararaca Snake Venoms

Bothrops jararaca is one of the most abundant venomous snake species in Brazil. It is primarily a nocturnal and generalist animal, however, it exhibits a notable ontogenetic shift in diet, feeding mainly on arthropods, lizards, and amphibians (ectothermic prey) through its juvenile phase and on small mammals (endothermic animals) during adult life. Due to its broad geographical distribution, this species is responsible for the majority of the accidents by Bothrops genus in Brazil. Studies on envenomation cases with newborn and adult B. jararaca snakes have shown distinct patterns, mainly related to blood coagulation disorders, which seems to be prominent in accidents with newborn specimens. Moreover, it has been demonstrated that the Brazilian commercial antibothropic antivenom, which is produced by immunization with adult venom, is less effective in neutralizing newborn venom effects. In this study we analyzed the venom gland transcriptome of newborn snake specimens and compared the content of toxin transcripts with that of adult specimens. We demonstrate that upon B. jararaca development, its repertoire of mRNAs encoding toxins changes both qualitatively and quantitatively and these alterations are associated with the venom proteome profiles and pharmacological activities displayed by newborn and adult specimens

Use of \u3cem\u3eN\u3c/em\u3e-Alkane Technique to Estimate Sheep Dry Matter Intake

Given the complexity of evaluating intake on grazing, some compounds have been studied to promote qualitative and quantitative estimates of animal physiology. In this sense, the technique using n-alkanes as a marker has been used in several animal species, especially in grazing ruminants (Dove and Mayes 1996). By definition, validation under grazing or browsing conditions is not possible, because actual intakes are unknown (Dove and Mayes 2005). Thus, the aim of the study was to evaluate the methodology of n-alkanes to estimate herbage intake by sheep in metabolic cages

Transcriptome analysis of Loxosceles laeta (Araneae, Sicariidae) spider venomous gland using expressed sequence tags

<p>Abstract</p> <p>Background</p> <p>The bite of spiders belonging to the genus <it>Loxosceles </it>can induce a variety of clinical symptoms, including dermonecrosis, thrombosis, vascular leakage, haemolysis, and persistent inflammation. In order to examine the transcripts expressed in venom gland of <it>Loxosceles laeta </it>spider and to unveil the potential of its products on cellular structure and functional aspects, we generated 3,008 expressed sequence tags (ESTs) from a cDNA library.</p> <p>Results</p> <p>All ESTs were clustered into 1,357 clusters, of which 16.4% of the total ESTs belong to recognized toxin-coding sequences, being the Sphingomyelinases D the most abundant transcript; 14.5% include "possible toxins", whose transcripts correspond to metalloproteinases, serinoproteinases, hyaluronidases, lipases, C-lectins, cystein peptidases and inhibitors. Thirty three percent of the ESTs are similar to cellular transcripts, being the major part represented by molecules involved in gene and protein expression, reflecting the specialization of this tissue for protein synthesis. In addition, a considerable number of sequences, 25%, has no significant similarity to any known sequence.</p> <p>Conclusion</p> <p>This study provides a first global view of the gene expression scenario of the venom gland of <it>L. laeta </it>described so far, indicating the molecular bases of its venom composition.</p

A validação da distribuição de espécies através de modelos preditivos: casos de estudo para a ilha da madeira

Os modelos preditivos de distribuição de espécies são uma importante ferramenta para lidar com a falta de informação biogeográfica existente para a maior parte dos taxa. Com esta técnica, estabelece -se uma relação entre a variável dependente (presença/ausência de uma espécie) e um conjunto de variáveis potencialmente preditoras, e é criado um mapa com a probabilidade de presença da espécie para uma determinada área de interesse. Neste capítulo, é usado o programa Maxent para criar modelos de distribuição potencial de um conjunto seleccionado de espécies, e os resultados obtidos são discutidos com base no conhecimento de especialistas nessas espécies.ABSTRACT: Predictive models of species distribution emerge as a valuable tool for tackling the lack of distributional information on most taxa. A function between the dependente variable (presence/absence of the species) and a set of potential predictors is established, and a map is generated for the focus area, indicating the probability of presence of the species. In this chapter, we use Maxent to develop potential distribution models for a number of selected species and we discuss the results on the basis of expert knowledge

Some aspects of the venom proteome of the Colubridae snake Philodryas olfersii revealed from a Duvernoy’s (venom) gland transcriptome

AbstractWe investigated the putative toxins of Philodryas olfersii (Colubridae), a representative of a family of snakes neglected in venom studies despite their growing medical importance. Transcriptomic data of the venom gland complemented by proteomic analysis of the gland secretion revealed the presence of major toxin classes from the Viperidae family, including serine proteases, metalloproteases, C-type lectins, Crisps, and a C-type natriuretic peptide (CNP). Interestingly, the phylogenetic analysis of the CNP precursor showed it as a linker between two related precursors found in Viperidae and Elapidae snakes. We suggest that these precursors constitute a monophyletic group derived from the vertebrate CNPs