CO2 emissions from a spark ignition engine operatin on natural-hydrogen blends (HCNG)

The addition of hydrogen to natural gas could be a short-term alternative to today’s fossil fuels, as greenhouse gas emissions may be reduced. The aim of this study is to evaluate the emissions and performance of a spark ignition engine fuelled by pure natural gas, pure hydrogen, and different blends of hydrogen and natural gas (HCNG). Increasing the hydrogen fraction leads to variations in cylinder pressure and CO2 emissions. In this study, a combustion model based on thermodynamic equations is used, considering separate zones for burned and unburned gases. The results show that the maximum cylinder pressure rises as the fraction of hydrogen in the blend increases. The presence of hydrogen in the blend leads to a decrease in CO2 emissions. Due to the properties of hydrogen, leaner fuel–air mixtures can be used along with the appropriate spark timing, leading to an improvement in engine emissions with no loss of performance

UNIDAD III: TECNICAS DE RECOPILACION Y REGISTRO DE DATOS

SOLO VISION PROYECTABLE

1.3 MÉTODOS Y TÉCNICAS DE LA INVESTIGACIÓN

SÓLO VISIÓN PROYECTABLE

Bottle aging and storage of wines: a review

Wine is perhaps the most ancient and popular alcoholic beverage worldwide. Winemaking practices involve careful vineyard management alongside controlled alcoholic fermentation and potential aging of the wine in barrels. Afterwards, the wine is placed in bottles and stored or distributed in retail. Yet, it is considered that wine achieves its optimum properties after a certain storage time in the bottle. The main outcome of bottle storage is a decrease of astringency and bitterness, improvement of aroma and a lighter and more stable color. This is due to a series of complex chemical changes of its components revolving around the minimized and controlled passage of oxygen into the bottle. For this matter, antioxidants like sulfur oxide are added to avoid excessive oxidation and consequent degradation of the wine. In the same sense, bottles must be closed with appropriate stoppers and stored in adequate, stable conditions, as the wine may develop unappealing color, aromas and flavors otherwise. In this review, features of bottle aging, relevance of stoppers, involved chemical reactions and storage conditions affecting wine quality will be addressed.The research leading to these results was funded by FEDER under the program Interreg V-A Spain-Portugal (POPTEC) 2014-2020 ref. 0377_IBERPHENOL_6_E and ref. 0181_NANOEATERS_ 01_E; to Xunta de Galicia supporting with the Axudas Conecta Peme the IN852A 2018/58 NeuroFood Project and the program EXCELENCIA-ED431F 2020/12; to Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003) and by the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBIJTI-2019), the JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The research leading to these results was supported by MICINN supporting the Ramón & Cajal grant for M.A. Prieto (RYC-2017-22891); by Xunta de Galicia and University of Vigo supporting the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096).info:eu-repo/semantics/publishedVersio

Twitching and swimming motility play a role in Ralstonia solanacearum pathogenicity

Ralstonia solanacearum is a bacterial plant pathogen causing important economic losses worldwide. In addition to the polar flagella responsible for swimming motility, this pathogen produces type IV pili (TFP) that govern twitching motility, a flagellum-independent movement on solid surfaces. The implication of chemotaxis in plant colonization, through the control flagellar rotation by the proteins CheW and CheA, has been previously reported in R. solanacearum. In this work, we have identified in this bacterium homologues of the Pseudomonas aeruginosa pilI and chpA genes, suggested to play roles in TFP-associated motility analogous to those played by the cheW and cheA genes, respectively. We demonstrate that R. solanacearum strains with a deletion of the pilI or the chpA coding region show normal swimming and chemotaxis but altered biofilm formation and reduced twitching motility, transformation efficiency, and root attachment. Furthermore, these mutants displayed wild-type growth in planta and impaired virulence on tomato plants after soil-drench inoculations but not when directly applied to the xylem. Comparison with deletion mutants for pilA and fliC encoding the major pilin and flagellin subunits, respectively showed that both twitching and swimming are required for plant colonization and full virulence. This work proves for the first time the functionality of a pilus-mediated pathway encoded by pil-chp genes in R. solanacearum, demonstrating that pilI and chpA genes are bona fide motility regulators controlling twitching motility and its three related phenotypes: virulence, natural transformation, and biofilm formation

Modelling multiple-simultaneous impact problems with a nonlinear smooth approach: pool/billiard application

Smooth approaches are able to model reasonably well contact/impact events between two bodies, showing some peculiarities when dealing with certain geometries and arising certain issues with the detection of the initial instant of contact. The characterization of multiple-simultaneous interaction systems, considering (or not) energy dissipation phenomena (mainly friction), is always an interesting research topic, addressed from different perspectives. In the present work, the process of design, optimization and verification of a multiple-impact, day-to-day multibody novel model is shown. Specifically, we have decided to focus on a pool/billiard game due to its geometry simplicity. The model involves several balls moving freely and rolling, suffering different kinds of contacts/impacts among them and against the cushions and the cloth. In this system, the proper modelling of both contact and friction forces in the multiple, simultaneous contacts and impacts events is critical to obtain consistent results. In addition, these forces are complicated to model because of its nonlinear behaviour. The different existing approaches when dealing with multiple-contact events are briefly described, along with their most distinctive features. Then, the interactions identified on the model are implemented using several nonlinear contact-force models, following a smooth-based approach and considering friction phenomena, aiming at determining the most suitable set of both contact and friction force models for each of these implemented interactions, which take place simultaneously, thus resulting in a complex system with multiple impacts. Subsequently, the solving method that provides the most accurate results at the minimum computational cost is determined by testing a simple shot. Finally, the different interactions on the model are verified using experimental results and previous works. One of the main goals of this work is to show the some of the issues that arise when dealing with multiple-simultaneous impact multibody systems from a smooth-contact approach, and how researchers can deal with them.The authors would like to thank the Spanish Government through the MCYT Project "RETOS2015: sistema de monitorización integral de conjuntos mecánicos críticos para la mejora del mantenimiento en el transportemaqstatus". The authors would also like to acknowledge the support received by the Community of Madrid through its multiyear agreement with University Carlos III focused on its policy "Excelencia para el Profesorado Universitario". Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature

State-of-the-art of analytical techniques to determine food fraud in olive oils

The benefits of the food industry compared to other sectors are much lower, which is why producers are tempted to commit fraud. Although it is a bad practice committed with a wide variety of foods, it is worth noting the case of olive oil because it is a product of great value and with a high percentage of fraud. It is for all these reasons that the authenticity of olive oil has become a major problem for producers, consumers, and legislators. To avoid such fraud, it is necessary to develop analytical techniques to detect them. In this review, we performed a complete analysis about the available instrumentation used in olive fraud which comprised spectroscopic and spectrometric methodology and analyte separation techniques such as liquid chromatography and gas chroma-tography. Additionally, other methodology including protein-based biomolecular techniques and analytical approaches like metabolomic, hhyperspectral imaging and chemometrics are discussed.The research leading to these results was supported by MICINN with the Ramón&Cajal grant for M. A. Prieto (RYC-2017-22891); by Xunta de Galicia and University of Vigo supporting the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096) and the pre-doctoral grants for A. G. Pereira (ED481A-2019/0228) and P. García-Oliveira (ED481A-2019/295) and by University of Vigo supporting the predoctoral grant for M. Carpena (Uvigo-00VI 131H 6410211).info:eu-repo/semantics/publishedVersio

Secondary aroma: influence of wine microorganisms in their aroma profile

Aroma profile is one of the main features for the acceptance of wine. Yeasts and bacteria are the responsible organisms to carry out both, alcoholic and malolactic fermentation. Alcoholic fermentation is in turn, responsible for transforming grape juice into wine and providing secondary aromas. Secondary aroma can be influenced by different factors; however, the influence of the microorganisms is one of the main agents affecting final wine aroma profile. Saccharomyces cerevisiae has historically been the most used yeast for winemaking process for its specific characteristics: high fermentative metabolism and kinetics, low acetic acid production, resistance to high levels of sugar, ethanol, sulfur dioxide and also, the production of pleasant aromatic compounds. Nevertheless, in the last years, the use of non-saccharomyces yeasts has been progressively growing according to their capacity to enhance aroma complexity and interact with S. cerevisiae, especially in mixed cultures. Hence, this review article is aimed at associating the main secondary aroma compounds present in wine with the microorganisms involved in the spontaneous and guided fermentations, as well as an approach to the strain variability of species, the genetic modifications that can occur and their relevance to wine aroma construction.The research leading to these results was supported by FEDER under the program Interreg V-A Spain-Portugal (POPTEC) 2014–2020 ref. 0377_IBERPHENOL_6_E and ref. 0181_NANOEATERS_ 01_E; by Xunta de Galicia supporting with the Axudas Conecta Peme the IN852A 2018/58 NeuroFood Project and the program EXCELENCIA-ED431F 2020/12; by EcoChestnut Project (Erasmus+ KA202) that supports the work of M. Carpena; by Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003) and by the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019), the JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The research leading to these results was supported by MICINN with the Ramón&Cajal grant for M. A. Prieto (RYC-2017-22891) and the Juan de la Cierva_incorporación grant for P. Otero (IJCI-2016-27774); by Xunta de Galicia and University of Vigo supporting the postdoctoral grant of M. Fraga-Corral (ED481B-2019/096) and the pre-doctoral grant for P. García-Oliveira (ED481A-2019/295).info:eu-repo/semantics/publishedVersio

Mutation Analysis in Regulator DNA-Binding Regions for Antimicrobial Efflux Pumps in 17,000 Pseudomonas aeruginosa Genomes

Mutations leading to upregulation of efflux pumps can produce multiple drug resistance in the pathogen Pseudomonas aeruginosa. Changes in their DNA binding regions, i.e., palindromic operators, can compromise pump depression and subsequently enhance resistance against several antibacterials and biocides. Here, we have identified (pseudo)palindromic repeats close to promoters of genes encoding 13 core drug-efflux pumps of P. aeruginosa. This framework was applied to detect mutations in these repeats in 17,292 genomes. Eighty-nine percent of isolates carried at least one mutation. Eight binary genetic properties potentially related to expression were calculated for mutations. These included palindromicity reduction, mutation type, positioning within the repeat and DNA-bending shift. High-risk ST298, ST308 and ST357 clones commonly carried four conserved mutations while ST175 and the cystic fibrosis-linked ST649 clones showed none. Remarkably, a T-to-C transition in the fourth position of the upstream repeat for mexEF-oprN was nearly exclusive of the high-risk ST111 clone. Other mutations were associated with high-risk sublineages using sample geotemporal metadata. Moreover, 1.5% of isolates carried five or more mutations suggesting they undergo an alternative program for regulation of their effluxome. Overall, P. aeruginosa shows a wide range of operator mutations with a potential effect on efflux pump expression and antibiotic resistance.This research was funded by Acción Estratégica en Salud from the ISCIII, grant MPY 509/19. This research was also supported by Personalized and Precision Medicine grant from the Instituto de Salud Carlos III (MePRAM Project, PMP22/00092), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea-NextGenerationEU.S