A produção de hidrogênio verde no refino

Cresce no mundo a busca por soluções que conduzam a descarbonização da economia. Muitos países se comprometeram a uma descarbonização profunda de suas economias até 2050 de acordo com o Acordo de Paris. O hidrogênio é considerado por muitos autores e governos como uma peça importante neste sentido. Atualmente, mais de 90% da produção de hidrogênio provém de origens fósseis. O Brasil já possui um parque instalado de hidrogênio e a principal técnica é a reforma a vapor de hidrocarbonetos. O fato de o Brasil ser um dos maiores produtores de etanol do mundo, bem como a logística eficiente, contribuem para o etanol ser um candidato a produção do chamado hidrogênio verde. A técnica de reforma a vapor pode ser adaptada para o processamento de biocombustíveis com alterações pouco complexas e já há licenciadores oferecendo a tecnologia. É uma oportunidade de relativo baixo custo para implantação. O etanol pode ser processado de forma total ou junto com hidrocarbonetos. Isto ajuda a dar flexibilidade na operação da unidade de acordo com o cenário de custos da matérias-primas. O hidrogênio verde a partir do etanol apresenta custo competitivo se comparado ao hidrogênio produzido a partir da eletrólise. Ao compararmos com a obtenção de hidrogênio a partir da reforma a vapor do gás natural e hidrocarbonetos, se justificaria apenas em cenários de preços bastante elevados do gás natural. A segurança energética, a aplicação para créditos de carbono e aplicação em outros combustíveis de baixo teor de carbono podem justificar o investimento e a técnica atualmente. Ressalta-se que a tecnologia de reforma a vapor é considerada madura tecnologicamente e confiável, o que diminui incertezas aos produtores.The research for solutions that lead to the decarbonization of the economy is growing worldwide. Many countries have committed to a deep decarbonization of their economies by 2050 in line with the Paris Agreement. Hydrogen is considered by many authors and governments as an important piece in this regard. Currently, more than 90% of hydrogen production comes from fossil sources. Brazil already has an industrial park of hydrogen production, and the main technique is steam reforming of hydrocarbons. The fact that Brazil is one of the largest ethanol producers in the world, as well as efficient logistics, makes ethanol attractive as a candidate to produce so-called green hydrogen. The steam reforming technique can be adapted for the processing of biofuels with little complex changes and there are already licensees that have the technology. It is a relatively low-cost opportunity to deploy. Ethanol can be processed as a whole or together with hydrocarbons. This helps to give flexibility in the operation of the unit according to the scenario of costs of raw materials. Green hydrogen from ethanol has a competitive cost compared to hydrogen produced from electrolysis. When compared with obtaining hydrogen from steam reforming of natural gas and hydrocarbons, it would only be justified in scenarios of very high natural gas prices. National energy security, application for carbon credits and new fuels of low carbon content, can justify the necessary investment. It should be noted that steam reforming technology is considered technologically mature and reliable, which reduces uncertainties for producers

Production of androgenetic barley doubled haploid lines

A cultura de anteras permite a obtenção de linhagens homozigotas em uma geração, em vez das sete requeridas pelos programas convencionais de melhoramento. Essa técnica encontra-se bem estabelecida com respeito a cevada (Hordeum vulgare L.), embora a resposta seja muito influenciada pelo genótipo e pelas condições de cultivo das plantas doadoras. Por isso, torna-se importante otimizar meios e métodos, buscando satisfazer os requerimentos específicos de cada material usado no trabalho. O objetivo deste trabalho foi avaliar a capacidade androgenética de híbridos F1 de cevada e estabelecer um protocolo eficiente de regeneração de duplo-haplóides, para tornar possível sua utilização em programas de melhoramento. Dois meios de cultura, N6 e MS modificados, foram utilizados para indução de androgênese. Avaliou-se a freqüência de anteras responsivas e de regeneração de plantas verdes, e a porcentagem de albinismo e de duplicação espontânea. Os resultados mostram que a porcentagem média de anteras responsivas no meio N6 (30,32%) foi maior do que no meio MS (6,39%). Houve uma considerável influência do genótipo em relação a todas as variáveis analisadas. No total, 192 genótipos duplo-haplóides, originados de diferentes cruzamentos, foram cultivados até a produção de grãos. As sementes de cada genótipo foram multiplicadas, para avaliação agronômica.Anther culture allows obtention of homozygous lines in one generation instead of seven required by conventional breeding programs. In barley (Hordeum vulgare L.) this technique is well-established, but response is greatly influenced by genotype and growing conditions of donor plants. Therefore, an important goal is to adapt media and methods, aiming to satisfy the specific requirements of every material one has been working with. In this paper androgenetic capacity of F1 hybrids is evaluated and an efficient protocol for regeneration of barley doubled haploids is established in order to make possible their utilization in breeding programs. Two culture media, modified N6 and MS, were employed for induction of androgenesis. Frequency of responsive anthers, green plant regeneration, albinism, and spontaneous doubling were evaluated. Results show that average percentage of responsive anthers was greater in N6 (30.32%) than in MS (6.39%) medium. There was a considerable influence of the genotype for all traits. A total of 192 doubled haploid lines were obtained from different crosses. These lines set seed and were multiplied for agronomic testing in the field

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat