Unitized regenerative polymeric fuel cell modeling

The research's objective is to have a single machine to function as fuel cell and electrolyser based and needs, that is to say, unitized regenerative fuel cell (when fed to the machine with electric power and water flows will be obtained and H2 and O2 and conversely when the machine is fuelled with H2 and O2 will get water, heat and electricity) The study focuses on polymeric fuel cells and polymeric electrolysers. The development of this machine will make a very significant cost reduction (currently to use hydrogen as an energy store needed the electrolyser and fuel cell) as a single machine may replace the fuel cell and electrolyser. The achievement of the objective mentioned above, have been going by completing a series of stages. The stages addressed in this work are: ¿ A first stage, which will be studied in detail the polymeric fuel cells and polymeric electrolysers, in order to see the similarities between the machines and to design the unitized regenerative fuel cell. ¿ A second stage of simulation, which will develop models to show the behaviour of the unitized regenerative fuel cell and compare results with those obtained from the theoretical. ¿ A third stage of model verification generated polymer fuel cells and electrolyzers polymer on the market

CeO2-promoted Cu2O-based catalyst sprayed on the gas diffusion layer for the electroreduction of carbon dioxide to ethylene

The development of efficient and selective catalysts for the carbon dioxide reduction reaction (CO2RR) is crucial for sustainable energy and chemical synthesis. In this work, CeO2-y (y = C (cubic) and R (rod)) was incorporated into Cu2O nanocube electrocatalyst as a promoter for ethylene (C2H4) production. The results demonstrate that the catalyst with a loading of 5 wt% crystalline CeO2-C exhibits competitive activity and stability for ethylene production compared to pristine Cu2O. Under optimized reaction conditions of −250 mA cm−2 current density and 1 M KOH electrolyte, the Cu2O–5CeO2-C catalyst achieved a faradaic efficiency (FE) of ∼53% for C2H4 production, while maintaining stability over a period of 120 minutes. In contrast, non-promoted Cu2O exhibited a lower FE for C2H4 (∼38%) and experienced partial deactivation after 45 minutes. The characterization of the catalysts before and after the reaction revealed that the interaction between Cu2O and CeO2-C creates intrinsic sites (Cux–CeO2−x; Cux = Cu2+, Cu+, and Cu0) for the binding of CO2 and H2O molecules. Moreover, the Cu2O–5CeO2-C catalyst outperforms other reported systems in terms of FE and partial current density for C2H4 production. It requires a lower potential (−0.98 V vs. RHE) to operate at the same electrolyte concentration. This finding highlights the promising nature of Cu2O–5CeO2-C as an efficient and cost-effective catalyst for C2H4 production

Assessment of Hydrogen as suistinable clean energy

The progressive depletion of fossil fuels and their high contribution to the energy supply in this modern society forces that will be soon replaced by renewable fuels. But the dispersion and alternation of renewable energy production also undertake to reduce their costs to use as energy storage and hydrogen carrier. It is necessary to develop technologies for hydrogen production from all renewable energy storage technologies and the development of energy production from hydrogen fuel cells and cogeneration and tri generation systems. In order to propel this technological development discussed where the hydrogen plays a key role as energy storage and renewable energy, the National Centre of Hydrogen and Fuel Cell Technology Experimentation in Spain equipped with installations that enable scientific and technological design, develop, verify, certify, approve, test, measure and, more importantly, the facility ensures continuous operation for 24 hours a day, 365 days year. At the same time, the system is scalable so as to allow continuous adaptation of new technologies are developed and incorporated into the assembly to verify integration at the same time it checks the validity of their development. The transformation sector can be said to be the heart of the system, because without neglecting the other sectors, this should prove the validity of hydrogen as a carrier - energy storage are important efforts that have to do to demonstrate the suitability of fuel cells or internal combustion systems to realize the energy stored in hydrogen at prices competitive with conventional systems. The multiple roles to meet the fuel cells under different conditions of operation require to cover their operating conditions, many different sizes and applications. The fourth area focuses on integration is an essential complement within the installation. We must integrate not only the electricity produced, but also hydrogen is used and the heat generated in the process of using hydrogen energy. The energy management in its three forms: hydrogen chemical, electrical and thermal integration requires complicated and require a logic and artificial intelligence extremes to ensure maximum energy efficiency at the same time optimum utilization is achieved. Verification of the development and approval in the entire production system and, ultimately, as a demonstrator set to facilitate the simultaneous evolution of production technology, storage and distribution of hydrogen fuel cells has been assessed

O mundo que se tornou visível através do afetivo

Affect studies is part of a renewed search for modes of ethnographic theory and critique that looks for ways to describe what precedes and exceeds the categorical in the labors of living through historical presents. For me, affect came into view through a slowed ethnographic practice attuned to the forms and forces unfolding in scenes and encounters. In the world affect brought into view, the point of analysis was not to track the predetermined effects of abstractable logics and structures but, rather, to compose a register of the lived affects of the things that took place in a social-aesthetic-materialpolitical worlding. In the world that affect proposed, things threw together, perhaps with a great deal of force, to become recognizable as something to be in, or near, or to oppose and resist, but it was always still an approximate composition of what was happening. Ethnographic writing began, again, to try to describe collective states and sensibilities hitting people and traversing otherwise incommensurate things, pulling the apparatus of conceptualization itself into a tricky alignment with slow ethnography’s immanent concerns and with the concerns of the worlds it was trying to traceLos estudios sobre los afectos y lo afectivo (Affect studies) hacen parte de una reciente búsqueda etnográfica por encontrar nuevas formas de describir lo que precede y excede en aquellas categorías con que definimos las labores de la vida de nuestro presente histórico. Para mí, lo afectivo apareció a través de una práctica etnográfica detenida, atenta, y en sintonía con las formas y fuerzas que se desarrollan en las escenas y en los encuentros. En el mundo de lo afectivo, el punto de análisis ya no era rastrear los efectos predeterminados de las lógicas y estructuras abstraíbles sino, más bien, componer un registro vivencial en donde ocurren cosas en relación al mundo material, social, estético, y político. Asimismo, en el mundo propuesto por lo afectivo, las cosas se empezaron a juntar, quizás con mucha fuerza, para hacerse reconocibles como algo en lo que se está, o se acerca, que opone y se resiste, pero que siempre es una composición aproximada de lo que ha sucedido. La escritura etnográfica también comenzó a narrar estados colectivos y sensibilidades que afectaban a las personas y que atravesaban cosas que, de otro modo, serían inconmensurables; haciendo que el aparato de la conceptualización se alinease con las preocupaciones inmanentes de dicha etnografía detenida y con las preocupaciones de los mundos que yo intentaba rastrear.Estudos sobre os afetos e afetivo (Affect studies) fazem parte de uma recente missão etnográfica para encontrar novas maneiras de descrever o que precede e excede as categorias que definem o trabalho da vida de nosso presente histórico. Para mim, o afetivo apareceu através de uma prática etnográfica cuidadosa, atenta, e em linha com as formas e as forças de desenvolvimento nas cenas e encontros. No mundo do afetivo, o ponto da análise não era rastrear os efeitos padrão de estruturas lógicas e abstraível mas sim compor um registro experimental onde as coisas acontecem em relação ao material, social, estético e mundo político. Também no mundo afetivo proposta, as coisas começaram a se reunir, talvez muito difícil, para ser reconhecido como algo que é ou abordagens que se opõe e resiste, mas é sempre uma composição aproximada do que aconteceu. A escrita etnográfica também começou a narrar estados coletivos e sensibilidades que afetavam as pessoas e passavam por coisas que de outro modo seriam incomensuráveis; fazendo o aparato de conceitualização alinhar-se com as preocupações imanentes de tal etnografia presa e com as preocupações dos mundos que eu estava tentando rastrea

Pathogenicity island cag, vacA and IS605 genotypes in Mexican strains of Helicobacter pylori associated with peptic ulcers

<p>Abstract</p> <p>Background</p> <p><it>Helicobacter pylori </it>is associated with chronic gastritis, peptic ulcers, and gastric cancer. Two major virulence factors of <it>H. pylori </it>have been described: the pathogenicity island <it>cag </it>(<it>cag </it>PAI) and the vacuolating cytotoxin gene (<it>vacA</it>). Virtually all strains have a copy of <it>vacA</it>, but its genotype varies. The <it>cag </it>PAI is a region of 32 genes in which the insertion of IS<it>605 </it>elements in its middle region has been associated with partial or total deletions of it that have generated strains with varying virulence. Accordingly, the aim of this work was to determine the <it>cag </it>PAI integrity<it>, vacA </it>genotype and IS<it>605 </it>status in groups of isolates from Mexican patients with non-peptic ulcers (NPU), non-bleeding peptic ulcers (NBPU), and bleeding peptic ulcers (BPU).</p> <p>Methods</p> <p>The <it>cag </it>PAI integrity was performed by detection of eleven targeted genes along this locus using dot blot hybridization and PCR assays. The <it>vacA </it>allelic, <it>cag </it>PAI genotype 1 and IS<it>605 </it>status were determined by PCR analysis.</p> <p>Results</p> <p>Groups of 16-17 isolates (n = 50) from two patients with NPU, NBPU, and BPU, respectively, were studied. 90% (45/50) of the isolates harbored a complete <it>cag </it>PAI. Three BPU isolates lacked the <it>cag </it>PAI, and two of the NBPU had an incomplete <it>cag </it>PAI: the first isolate was negative for three of its genes, including deletion of the <it>cagA </it>gene, whereas the second did not have the <it>cagM </it>gene. Most of the strains (76%) had the <it>vacA </it>s1b/m1 genotype; meanwhile the IS<it>605 </it>was not present within the <it>cag </it>PAI of any strain but was detected elsewhere in the genome of 8% (4/50).</p> <p>Conclusion</p> <p>The patients had highly virulent strains since the most of them possessed a complete <it>cag </it>PAI and had a <it>vacA </it>s1b/m1 genotype. All the isolates presented the <it>cag </it>PAI without any IS<it>605 </it>insertion (genotype 1). Combined <it>vacA </it>genotypes showed that 1 NPU, 2 NBPU, and 1 BPU patients (66.6%) had a mixed infection; coexistence of <it>H. pylori </it>strains with different <it>cag </it>PAI status was observed in 1 NBPU and 2 BPU (50%) of the patients, but only two of these patients (NBPU and BPU) had different <it>vacA </it>genotypes.</p

Three-dimensional geometric morphometrics for studying floral shape variation

Variation in floral shape is of major interest to evolutionary and pollination biologists, plant systematists and developmental geneticists. Quantifying this variation has been difficult due to the three-dimensional (3D) complexity of angiosperm flowers. By combining 3D geometric representations of flowers obtained by micro-computed tomography scanning with geometric morphometric methods, well established in zoology and anthropology, floral shape variation can be analyzed quantitatively, allowing for powerful interpretation and visualization of the resulting patterns of variation

Modeling the SARS-CoV-2 sublineages XBB and BQ.1 in Mexico, considering multiple vaccinations, booster dose, waning immunity and cross-immunity

In a population with ongoing vaccinations, the trajectory of a pandemic is determined by how the virus spreads in the unvaccinated, vaccinated without boosters, and vaccinated with boosters, which will exhibit distinct transmission dynamics based on different levels of natural and vaccine-induced immunity. We found that enhancing the use of face masks in a partially vaccinated population is associated with a reduction of new infections, hospitalizations, and deaths. We highly recommend the use of a face mask with at least a 50% efficiency, such as improved cloth and surgical face masks, due to its effectivity and cost ratio. Our simulations indicated that there may be two upcoming Omicron waves (in the last months of 2022 and in May 2023). The magnitude of these waves will be 75% and 40% lower than their prior wave. Moreover, the size of these waves is heavily influenced by immunity parameters like waning immunity and cross-immunity protection. Hence, we recommend continuing the use of face masks to decrease transmission because we are not developing sterilizing immunity if we get infected by a prior sublineage, meaning that we can still get infected regardless of the acquired immunity

Molecular diversity within clones of cv. Tannat (Vitis vinifera)

DNAs from 9 clones of cv. Tannat (Vitis vinifera) were analyzed at 89 microsatellite loci. Only one, VMCNg 1d12, showed a differential pattern that separated the clones in two groups. The statistical analysis of concentrations for aroma compounds from microvinifications also resulted in the same two groupings of clones. Many analyzed microsatellite loci amplified only one allele, implying that Tannat is a highly homozygous variety. For a given set of 15 microsatellites the level of homozygosity was 53 % for Tannat, in contrast to 6 % for Pinot, 20 % for both Cabernet Franc and Chardonnay and 33 % for Cabernet Sauvignon. We provide molecular data for Tannat, originating from southwestern France and nowadays becoming the emblematic cultivar of Uruguayan fine red wines. We also report a correlation between aroma-related compounds and molecular markers within clones of a cultivar.