Microbial oils are proposed as a suitable alternative to petroleum‐based chemistry in terms of environmental preservation. These oils have traditionally been studied using sugar‐based feedstock, ...which implies high costs, substrate limitation, and high contamination risks. In this sense, low‐cost carbon sources such as volatile fatty acids (VFAs) are envisaged as promising building blocks for lipid biosynthesis to produce oil‐based bioproducts. VFAs can be generated from a wide variety of organic wastes through anaerobic digestion and further converted into lipids by oleaginous yeasts (OYs) in a fermentation process. These microorganisms can accumulate in the form of lipid bodies, lipids of up to 60% wt/wt of their biomass. In this context, OY is a promising biotechnological tool for biofuel and bioproduct generation using low‐cost VFA media as substrates. This review covers recent advances in microbial oil production from VFAs. Production of VFAs via anaerobic digestion processes and the involved metabolic pathways are reviewed. The main challenges as well as recent approaches for lipid overproduction are also discussed.
Microbial oil are proposed as a suitable alternative to petroleum‐based chemistry in terms of environmental preservation. These oils have traditionally been studied using sugar‐based feedstock. VFAs rich digestate (VFAs) is envisaged as promising low‐cost substrate reducing process cost as well as allowing wastes valorisation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Representing Vulnerabilities in Contemporary Literature includes a collection of chapters exploring the ways in which recent literary representations of vulnerability may problematize its ...visibilization from an ethical and aesthetic perspective. Recent technological and scientific developments have accentuated human vulnerability in many and different ways at a cross-national, and even cross-species level. Disability, technological, and ecological vulnerabilities are new foci of interest that add up to gender, precarity, and trauma, among others, as forms of vulnerability in this volume. The literary visualization of these vulnerabilities might help raise social awareness of one's own vulnerabilities as well as those of others so as to bring about global solidarity based on affinity and affect. However, the literary representation of forms of vulnerability might also deepen stigmatization phenomena and trivialize the spectacularization of vulnerability by blunting readers' affective response toward those products that strive to hold their attention and interest in an information-saturated, global entertainment market.
•Agroindustrial wastes as potential feedstock for volatile fatty acids production.•Anaerobic fermentation of agroindustrial wastes contributes to circular economy.•High bioconversion yields (50–60%) ...were reached in batch and continuous reactors.•Fermentation effluents with high content of long-chain VFAs.•Firmicutes was identify as key phylum for anaerobic fermentation of carbohydrates.
This study evaluated the feasibility of the anaerobic digestion as a sustainable valorisation strategy for volatile fatty acids production from agroindustrial waste (cucumber, tomato and lettuce). High bioconversion efficiencies were reached by operating the reactors at 25 °C, 3 g VS·d−1·L−1 with pH adjustment. Cucumber fermentation achieved the highest bioconversion (52.6%), whereas tomato degradation was the least efficient bioprocess (40.1%) due to the low pH (5.6) that partially inhibited the hydrolytic and acidogenic activities. In all cases, carboxylic acid profiles were mainly composed of volatile fatty acids with even carbon number. The developed microbial community exhibited high hydrolytic and acidogenic activities associated to carbohydrates degradation. This microbial population was dominated by Firmicutes phylum and showed a lack of acetogenic bacteria related with CH4 production, resulting in a remarkably high VFAs accumulation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Serious games have proven to be a powerful tool in education to engage, motivate, and help students learn. However, the change in student knowledge after playing games is usually measured with ...traditional (paper) prequestionnaires–postquestionnaires. We propose a combination of game learning analytics and data mining techniques to predict knowledge change based on in‐game student interactions. We have tested this approach in a case study for which we have conducted preexperiments–postexperiments with 227 students playing a previously validated serious game on first aid techniques. We collected student interaction data while students played, using a game learning analytics infrastructure and the standard data format Experience API for Serious Games. After data collection, we developed and tested prediction models to determine whether knowledge, given as posttest results, can be accurately predicted. Additionally, we compared models both with and without pretest information to determine the importance of previous knowledge when predicting postgame knowledge. The high accuracy of the obtained prediction models suggests that serious games can be used not only to teach but also to measure knowledge acquisition after playing. This will simplify serious games application for educational settings and especially in the classroom easing teachers' evaluation tasks.
Lay Description
What is currently known about the subject matter
Serious games are a powerful tool to engage, motivate, and help students learn.
Pre‐post experiments are commonly used to measure knowledge acquisition.
Game learning analytics can be applied to interaction data from games.
What this paper adds
We present a two‐step approach combining game learning analytics and data mining to predict players' performance in serious games based on their interactions.
The approach is tested in a case study with pre‐post experiments collecting interaction data with 227 students playing a serious game to determine if performance can be accurately predicted.
The comparison of prediction models has helped to determine if pretest information is essential.
The highly accurate prediction models obtained suggest that games can be used to teach and measure knowledge acquisition after playing.
Implications of study findings for practitioners
The approach aims to simplify the measurement of players' learning with serious games.
It may be generalized at least to similar scenarios (e.g., games for procedural learning or game‐likesimulations) where similar interaction data are feasible.
Game mechanics and educational design should define the interaction data to capture.
Using an accepted standard tracking profile is a clear recommendation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Microalgae are regarded as a potential biomass source for biofuel purposes. With regard to bioethanol production, microalgae seem to overcome traditional substrate drawbacks. Enzymatic activities are ...responsible for carbon allocation and hence for carbohydrate profiles. Enzyme activities may be manipulated by metabolic engineering; however, this goal may also be achieved by controlling environmental conditions of the culture system. We outline the key-enzymes as well as the main operational conditions applied to microalgae growth (inorganic nutrient supplementation, irradiance and temperature) that affect carbohydrate synthesis on microalgae and cyanobacteria. Normally, harsh conditions are needed for such a goal and thus, arrested microalgae growth may occur. Potential strategies to avoid arrested growth, while enhancing carbohydrate accumulation, were also pointed out in this review.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study assessed the feasibility of melon and watermelon residues for the co-production of short-chain fatty acids (SCFAs) and hydrogen (H2) via single-stage anaerobic fermentation. The high ...content of carbohydrates and readily biodegradable organic matter in the wastes, along with the acid pH (5.6–5.8) imposed in the reactors, were key factors to reach high SCFAs and H2 co-production efficiencies. Mentioned conditions promoted a specialized microbial community dominated by Ruminococcus involved in the prevalence of the reverse β-oxidation pathway. This microbial metabolism caused the accumulation of isobutyric and caproic acids (76% of total SCFAs), resulting in a SCFAs production efficiency higher than 40% with concomitant high H2 production yields (395.5 and 62.7 mL H2/g volatile solids influent for melon and watermelon fermentation). A high hydraulic retention time (HRT) of 27 days, an organic loading rate of 3 g of volatile solids per day and liter of working volume and a fermentation temperature of 25 °C were also crucial for maximizing H2 production at acid pH. Overall, melon and watermelon wastes bioconversion efficiencies into H2 and SCFAs reached 64.0 and 58.7%, demonstrating the successful co-production of different bioproducts in a single-stage fermentation by establishing proper operational conditions.
•Single-stage fermentation successfully co-produced H2 and organic acids.•Isobutyric (41–44%) and caproic acids (32–35%) were the most abundant organic acids.•Reverse β-oxidation pathway prevalence resulted in high H2 and longer acids yields.•Reverse β-oxidation was mediated by Ruminococcus presence.•Operation conditions allowed the system to reach 58–64% efficiencies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The insulin-degrading enzyme (IDE) is a metalloendopeptidase with a high affinity for insulin. Human genetic polymorphisms in Ide have been linked to increased risk for T2DM. In mice, hepatic Ide ...ablation causes glucose intolerance and insulin resistance when mice are fed a regular diet.
These studies were undertaken to further investigate its regulatory role in glucose homeostasis and insulin sensitivity in diet-induced obesity.
To this end, we have compared the metabolic effects of loss versus gain of IDE function in mice fed a high-fat diet (HFD).
We demonstrate that loss of IDE function in liver (L-IDE-KO mouse) exacerbates hyperinsulinemia and insulin resistance without changes in insulin clearance but in parallel to an increase in pancreatic β-cell function. Insulin resistance was associated with increased FoxO1 activation and a ~2-fold increase of GLUT2 protein levels in the liver of HFD-fed mice in response to an intraperitoneal injection of insulin. Conversely, gain of IDE function (adenoviral delivery) improves glucose tolerance and insulin sensitivity, in parallel to a reciprocal ~2-fold reduction in hepatic GLUT2 protein levels. Furthermore, in response to insulin, IDE co-immunoprecipitates with the insulin receptor in liver lysates of mice with adenoviral-mediated liver overexpression of IDE.
We conclude that IDE regulates hepatic insulin action and whole-body glucose metabolism in diet-induced obesity via insulin receptor levels.
•Loss of hepatic IDE function exacerbates insulin resistance in mice fed a HFD.•Gain of hepatic IDE function improves insulin sensitivity in mice fed HFD.•Hepatic IDE appears to modulate insulin homeostasis via regulating β-cell function.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Los laboratorios audiovisuales abiertos son enclaves esenciales en la sociedad del conocimiento, el desarrollo de la cultura maker, y de la innovación abierta. En esta investigación basada en una ...metodología mixta se han utilizado técnicas cuantitativas y cualitativas como el análisis documental, grupo de discusión, la observación participante, entrevistas semiestructuradas en profundidad y la encuesta. Partiendo del análisis efectuado afirmamos que estos laboratorios fomentan la formación, la investigación, la producción audiovisual y artística de la ciudadanía en la lógica del procomún formando parte de la cultura de participación y por ende la construcción social, proporcionando un enriquecimiento y satisfacción a los participantes, mediante la colaboración y co-creación de proyectos. Nos encontramos por tanto con espacios donde el papel de los mediadores como agentes socioculturales es esencial.
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