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Among the approaches to facilitating negative CO2 emissions is biochar production. Biochar is generated in the pyrolysis of certain biomasses. In the pyrolysis process, carbon in the biomass is turned into a solid, porous, carbon-rich, and stable material that can be captured from the soil after a period of from a few decades to several centuries. In addition to this long-term carbon sequestration role, biochar is also beneficial for soil performance as it helps to restore soil fertility and improves the retention and diffusion of water and nutrients. This work presents a Life Cycle Assessment of different pyrolysis approaches for biochar production. Biomass pyrolysis is performed in a fixed-bed reactor, which operates at a mild temperature (550 °C). Biochar is obtained as solid product of the pyrolysis, but there are also liquid (bio-oil) and gaseous products (syngas). The pyrolysis gas is partly used to fulfil the energy demand of the pyrolysis process, which is highly endothermic. In the conventional approach, CO2 is produced during the combustion of syngas and emitted to the atmosphere. Another approach to facilitate CO2 capture and thus obtain more negative CO2 emissions in the pyrolysis process is burning syngas and bio-oil in a Chemical Looping Combustion unit. Life Cycle Assessment was performed of these approaches toward biomass pyrolysis to evaluate their environmental impact. The Chemical Looping Combustion approach significantly reduced the values of 7 of the 16 environmental impact indicators studied, along with the Global Warming Potential among them, it slightly increased the value of one indicator related to the use of fossil resources, and it maintained the values of the remaining 8 indicators. Environmental impact reduction occurs due to the avoidance of CO2 and NOx emissions with Chemical Looping Combustion. The CO2 balances of the different pyrolysis approaches with Chemical Looping Combustion configurations were compared with a base case, which constituted the direct combustion of wheat straw to obtain thermal energy. Direct biomass combustion for the production of 17.1 MJ of thermal energy had CO2 positive emissions of 0.165 kg. If the gaseous fraction was burned by Chemical Looping Combustion, CO2 was captured and the emissions became increasingly negative, until a value of −3.30 kg/17.1 MJ was generated. If bio-oil was also burned by this technology, the negative trend of CO2 emissions continued, until they reached a value of −3.66 kg. [ABSTRACT FROM AUTHOR]

The latest studies show that to achieve the Sustainable Development Goals on education, there must be a focus on adequately training higher education students. In this work, we present a study about the Life Cycle Analysis of knowledge of products and processes of engineering students. This aspect is very relevant in engineering education since it has direct implications on sustainability. The first step was to identify what the learning problems were, and taking them into account, a specific teaching sequence was designed and implemented over three academic years. Two activities, on an increasing level of complexity, of the application of Life Cycle Assessment are shown in this paper. The first one is the Life Cycle Analysis comparison between two steel and polypropylene pieces. The second one is the Life Cycle Analysis comparison between three different ends of life of a polypropylene piece: mechanical recycling, incineration, and landfill. Data on the evolution of students' marks while solving a "one step more difficult project" throughout these courses have been collected. The results show a generalized learning by the students about Life Cycle Analysis. [ABSTRACT FROM AUTHOR]

The environmental impacts of the manufacture of chitosan (CS) and polymeric poly(1‐trimethylsilyl‐1‐propyne) (PTMSP) mixed‐matrix membranes (MMMs) for CO2 separation by life cycle assessment (LCA) are compared. An ionic liquid of non‐reported toxicity is used in CS membranes to enhance the mechanical strength, and different fillers are used to increase mechanical and functional properties: ETS‐10, ZIF‐8, HKUST‐1, and Zeolite A. Results with the same CO2 permeation flux indicate that ETS‐10/IL‐CS is the membrane manufacture with highest impacts due to its lower permeability. When comparing impacts with same permeation areas, the polymeric one is the membrane with highest impacts. Biopolymer and polymer manufacture are the components with highest contribution to the total environmental impacts of each membrane. To decrease all their impacts below fossil polymer membrane for the same CO2 permeation flux, CS membranes permeabilities should be improved by a numerical factor of 1000, 100, and 2 for the ETS‐10, ZIF‐8, and HKUST‐1/IL‐CS MMMs, respectively. [ABSTRACT FROM AUTHOR]

Thyroid hormones have a fundamental impact on cardiac function that is mediated by genomic and nongenomic effects, alterations that condition physiological repercussions that lead to changes in frequency, contractility, rhythm and cardiac output as well as an increase in the incidence and prevalence of different cardiovascular diseases. This document presents an updated review of the implications that hyperthyroidism has in different cardiac conditions, including its importance in the evaluation of perioperative cardiovascular risk. [ABSTRACT FROM AUTHOR]

Kounis syndrome (KS) is a rare syndrome characterized by the co-occurrence of acute coronary syndromes in the setting of mast cell and platelet activation in response to hypersensitivity reactions. It can be manifested as coronary vasospasms, acute myocardial infarction, or stent thrombosis triggered by drugs, vaccines, foods, coronary stents, and insect bites. It is a life-threatening condition that needs to be adequately recognized for early diagnosis and appropriate treatment. In this case report, we present a 71-year-old patient with a history of arterial hypertension and non-ST elevation myocardial infarction six months earlier that was treated percutaneously with angioplasty plus stent implantation in the circumflex artery, who subsequently presented to the emergency department due to generalized itching associated with tongue swelling, dyspnea, and chest pain after ingestion of ciprofloxacin for the treatment of a urogenital infection. An electrocardiogram showed ST elevation in II, III, and aVF leads, and positive troponin; thus, a coronary arteriography was performed that showed complete thrombotic stent occlusion in the circumflex artery. Consequently, diagnosis of type 4b inferolateral acute myocardial infarction secondary to ciprofloxacin-triggered type III Kounis syndrome was made. The aim of this report is to understand the relationship between the allergic reaction to ciprofloxacin and the acute coronary syndrome, and to create awareness of the importance of early diagnosis and treatment of this potentially fatal syndrome. [ABSTRACT FROM AUTHOR]

Eco-design is includedwithin the framework of the standard for "Environmentalmanagement systems--Guidelines for incorporating Eco-design" (ISO 14006:2011). Eco-design process, as defined in standard, has six steps: (i) Specify product functions; (ii) Environmental assessment of products; (iii) Strategies of improvement; (iv) Environmental objectives; (v) Product specification; and (vi) Technical solutions. Step (ii), determination of the stage or process of the product life cycle that has the highest environmental impact; this is perhaps the most controversial step because the standard does not specify which tool should be used. This lack of specification has generated some distrust with regard to eco-design, hindering its development. In order to make a trustworthy eco-design, Life Cycle Assessment (LCA) should be applied as a tool for environmental impact quantification. The main objective of this work is to apply standardised eco-design methodology for the reduction of the environmental impact of an industrial product in Spain using LCA as a tool for the environmental product assessment. LCA standardised process (ISO 14040,14044:2006) is included in the eco-design process. A glass container intended for cough syrup delivery has been selected as an industrial product to be eco-designed. Following the methodology described, the overall normalised impact decreased 35.1% when a PET container substituted a glass container. Environmental impacts have been reduced following standardised eco-design and LCA methodologies, serving as an example to industry and administration regarding how to eco-design with the confidence of obtaining reliable results. [ABSTRACT FROM AUTHOR]

Non-edible vegetable oils are characterized by high contents of free fatty acids (FFAs) that prevent from using the conventional basic catalysts for the production of biodiesel. In this work, solid acid catalysts are used for the simultaneous esterification and transesterification with methanol of the FFAs and triglycerides contained in sunflower oil acidified with oleic acid. Molybdenum oxide (MoO3), which has been seldom considered as a catalyst for the production of biodiesel, was used in bulk and alumina-supported forms. Results showed that bulk MoO3 is very active for both transesterification and esterification reactions, but it suffered from severe molybdenum leaching in the reaction medium. When supported on Al2O3, the MoO3 performance improved in terms of active phase utilization and stability though molybdenum leaching remained significant. The improvement of catalytic performance was ascribed to the establishment of MoO3-Al2O3 interactions that favored the anchorage of molybdenum to the support and the formation of new strong acidic centers, although this effect was offset by a decrease of specific surface area. It is concluded that the development of stable catalysts based on MoO3 offers an attractive route for the valorization of oils with high FFAs content. [ABSTRACT FROM AUTHOR]

The solid photocatalyst is dip-coated onto a 3D-printed sacrificial template made of ABS (acrylonitrile butadiene styrene) polymer, and such coated template is subsequently embedded in PDMS (polydimethylsiloxane) matrix to conform the body of the microreactor. The PDMS pre-polymer traps the photocatalyst nanoparticles while spreading across the ABS template, and once cured, this process leaves a continuous and homogeneous thin layer of photocatalytic nanoparticles intimately adhered to the microchannel polymer walls upon removal of the template with rinsing acetone. [Display omitted] • Innovative method for integrating Au@POM/TiO 2 nanoparticles onto silicone microreactors. • Effective adhesion of the photocatalysts to the microreactor channel walls. • Good catalytic performance of Au@POM/TiO 2 with only 0.18 % w/w. of Au nanoparticles. • Photoreduction of 4-nitrophenol performed as test reaction in continuous flow regime. Reproducible and controllable incorporation and immobilization of catalysts and other active particles onto silicone microreactor channels is still challenging. In this work, we present an innovative fabrication protocol to attain affordable, custom-designed photocatalytic microreactors in a fast and simple manner. In this protocol, a 3D-printed ABS microreactor mold is first dip-coated with the photocatalyst, and subsequently, the catalytic layer is transferred onto the microchannel walls by indirect immobilization during the silicone casting and scaffold removal step. Serpentine-shaped microreactors have been satisfactorily fabricated with Au@POM-impregnated TiO 2 nanoparticles (Au@POM/TiO 2 ; Au 0.18 % w/w, POM: H 3 PW 12 O 40) as the integrated photocatalytic layer. The suitability of our fabrication method has been validated on the basis of the excellent photocatalytic performance shown by the microreactors in a model test reaction such as the continuous-flow photoreduction of 4-nitrophenol to 4-aminophenol with NaBH 4 and monitored by UV–vis spectroscopy. [ABSTRACT FROM AUTHOR]

Background: Acute coronary syndrome is a rare complication of infectious endocarditis. We present the case of a patient with a bicuspid aortic valve who presented an acute ST elevation myocardial infarction (STEMI) of the inferior wall secondary to vegetation that generated obstruction of the ostium of the right coronary artery (RCA)., Case Summary: A 54-year-old patient with only a history of smoking was admitted for chest pain. An acute STEMI in the inferior wall was documented; he underwent an emergent coronary angiography, which showed a mass that obstructed the ostium of the RCA that did not allow its channelling. An angiotomography of the aorta was performed, where dissection was ruled out and the presence of a mass in the right coronary sinus that protruded towards the ostium of the coronary artery was confirmed. In the extension studies, a bicuspid aortic valve and thrombosis in the right brachial artery and in the infrarenal abdominal aorta were documented., Discussion: The case was taken to a medical meeting and given the embolic and mechanical compromise; it was decided to perform surgery where a mass that invaded the proximal segment of the RCA was resected. The histopathological study documented findings of vegetation; the cultures were positive for Staphylococcus epidermidis , and he finally received antibiotic and anticoagulation treatment., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)