Literatura europea, literaturas europeas

Para Milan Kundera el hecho de que Europa no haya conseguido pensar su literatura como una unidad histórica supone un fracaso intelectual irreparable. Sin embargo, aunque los intentos de componer esa Historia no han cesado, urge en las circunstancias actuales pensar esa unidad, imaginar una Europa que no dependa de los mercados, de los bancos ni tampoco de la política económica y turística. La diversidad y la voluntad de mantener las diferencias, que identifica a Europa, debería ir acompañada del deseo de establecer unos vínculos, de anclar la “idea de Europa”. El estudio de este vínculo es el eje que proponemos para el séptimo número de Extravío. Revista electrónica de literatura comparada

Case study-based learning using a computational tool to improve the understanding of the jet engine cycle for aerospace engineering degree students

[EN] In the current paper, a methodology combining a case study with a computational tool for aerospace engineering students is presented and discussed. The aim of this methodology is to improve the understanding of jet engine's operation through their thermodynamic cycle analysis, particularly focused on the effects of the main boundary conditions for an aircraft engine: altitude and flight velocity (or Mach). Additionally, the organization of the methodology as a case study performed in groups helps to facilitate student engagement, as well as the development of soft skills, such as teamwork ability. The experience of this methodology over the last 5 years shows that the activity is generally well perceived by the students, and also that there is a correlation between the engagement in this activity and the overall results achieved in the subject, confirming that the methodology helps to improve students' comprehension of the concepts behind engine performance. However, a few points of improvement for the near future are identified.Universitat Politecnica de Valencia, Grant/Award Number: E-20-21/204Piqueras, P.; De La Morena, J.; Bares-Moreno, P.; Sanchis Pacheco, EJ. (2021). Case study-based learning using a computational tool to improve the understanding of the jet engine cycle for aerospace engineering degree students. Computer Applications in Engineering Education. 29:1857-1870. https://doi.org/10.1002/cae.22427S185718702

Impact of Exhaust Gas Recirculation on Gaseous Emissions of Turbocharged Spark-Ignition Engines

[EN] Exhaust gas recirculation is one of the technologies that can be used to improve the efficiency of spark-ignition engines. However, apart from fuel consumption reduction, this technology has a significant impact on exhaust gaseous emissions, inducing a significant reduction in nitrogen oxides and an increase in unburned hydrocarbons and carbon monoxide, which can affect operation of the aftertreatment system. In order to evaluate these effects, data extracted from design of experiments done on a multi-cylinder 1.3 L turbocharged spark-ignition engine with variable valve timing and low-pressure exhaust gas recirculation (EGR) are used. The test campaign covers the area of interest for the engine to be used in new-generation hybrid electric platforms. In general, external EGR provides an approximately linear decrease of nitrogen oxides and deterioration of unburned hydrocarbon emissions due to thermal and flame quenching effects. At low load, the impact on emissions is directly linked to actuation of the variable valve timing system due to the interaction of EGR with internal residuals. For the same external EGR rate, running with high valve overlap increases the amount of internal residuals trapped inside the cylinder, slowing down combustion and increasing Unburnt hydrocarbon (HC) emissions. However, low valve overlap (i.e., low internal residuals) operation implies a decrease in oxygen concentration in the exhaust line for the same air-fuel ratio inside the cylinders. At high load, interaction with the variable valve timing system is reduced, and general trends of HC increase and of oxygen and carbon monoxide decrease appear as EGR is introduced. Finally, a simple stoichiometric model evaluates the potential performance of a catalyst targeted for EGR operation. The results highlight that the decrease of nitrogen oxides and oxygen availability together with the increase of unburned hydrocarbons results in a huge reduction of the margin in oxygen availability to achieve a complete oxidation from a theoretical perspective. This implies the need to rely on the oxygen storage capability of the catalyst or the possibility to control at slightly lean conditions, taking advantage of the nitrogen oxide reduction at engine-out with EGR.Piqueras, P.; De La Morena, J.; Sanchis-Pacheco, EJ.; Pitarch-Berná, R. (2020). Impact of Exhaust Gas Recirculation on Gaseous Emissions of Turbocharged Spark-Ignition Engines. Applied Sciences. 10(21):1-17. https://doi.org/10.3390/app10217634S1171021Kolodziej, C. P., Pamminger, M., Sevik, J., Wallner, T., Wagnon, S. W., & Pitz, W. J. (2017). Effects of Fuel Laminar Flame Speed Compared to Engine Tumble Ratio, Ignition Energy, and Injection Strategy on Lean and EGR Dilute Spark Ignition Combustion. SAE International Journal of Fuels and Lubricants, 10(1), 82-94. doi:10.4271/2017-01-0671Sjerić, M., Taritaš, I., Tomić, R., Blažić, M., Kozarac, D., & Lulić, Z. (2016). Efficiency improvement of a spark-ignition engine at full load conditions using exhaust gas recirculation and variable geometry turbocharger – Numerical study. Energy Conversion and Management, 125, 26-39. doi:10.1016/j.enconman.2016.02.047Grover, Jr., R. O., & Cleary, D. (2013). Correlating Measured Combustion Performance with CFD Predicted In-Cylinder Flows for a Spark-Ignition Direct-Injection (SIDI) Engine with Enhanced Charge Motion. SAE Technical Paper Series. doi:10.4271/2013-01-1090Costa, M., Catapano, F., Sementa, P., Sorge, U., & Vaglieco, B. M. (2016). Mixture preparation and combustion in a GDI engine under stoichiometric or lean charge: an experimental and numerical study on an optically accessible engine. Applied Energy, 180, 86-103. doi:10.1016/j.apenergy.2016.07.089Alagumalai, A. (2014). Internal combustion engines: Progress and prospects. Renewable and Sustainable Energy Reviews, 38, 561-571. doi:10.1016/j.rser.2014.06.014Dong, X., Wang, B., Yip, H. L., & Chan, Q. N. (2019). CO2 Emission of Electric and Gasoline Vehicles under Various Road Conditions for China, Japan, Europe and World Average—Prediction through Year 2040. Applied Sciences, 9(11), 2295. doi:10.3390/app9112295Vafamehr, H., Cairns, A., Sampson, O., & Koupaie, M. M. (2016). The competing chemical and physical effects of transient fuel enrichment on heavy knock in an optical spark ignition engine. Applied Energy, 179, 687-697. doi:10.1016/j.apenergy.2016.07.038Gröger, O., Gasteiger, H. A., & Suchsland, J.-P. (2015). Review—Electromobility: Batteries or Fuel Cells? Journal of The Electrochemical Society, 162(14), A2605-A2622. doi:10.1149/2.0211514jesPham, A., & Jeftic, M. (2018). Characterization of Gaseous Emissions from Blended Plug-In Hybrid Electric Vehicles during High-Power Cold-Starts. SAE Technical Paper Series. doi:10.4271/2018-01-0428Yamada, H., Inomata, S., & Tanimoto, H. (2017). Particle and VOC Emissions from Stoichiometric Gasoline Direct Injection Vehicles and Correlation Between Particle Number and Mass Emissions. Emission Control Science and Technology, 3(2), 135-141. doi:10.1007/s40825-016-0060-0Zinola, S., Raux, S., & Leblanc, M. (2016). Persistent Particle Number Emissions Sources at the Tailpipe of Combustion Engines. SAE Technical Paper Series. doi:10.4271/2016-01-2283Xie, F., Li, X., Su, Y., Hong, W., Jiang, B., & Han, L. (2016). Influence of air and EGR dilutions on improving performance of a high compression ratio spark-ignition engine fueled with methanol at light load. Applied Thermal Engineering, 94, 559-567. doi:10.1016/j.applthermaleng.2015.10.046Wei, H., Zhu, T., Shu, G., Tan, L., & Wang, Y. (2012). Gasoline engine exhaust gas recirculation – A review. Applied Energy, 99, 534-544. doi:10.1016/j.apenergy.2012.05.011Ghazikhani, M., Feyz, M. E., & Joharchi, A. (2010). Experimental investigation of the Exhaust Gas Recirculation effects on irreversibility and Brake Specific Fuel Consumption of indirect injection diesel engines. Applied Thermal Engineering, 30(13), 1711-1718. doi:10.1016/j.applthermaleng.2010.03.030Al-Qurashi, K., Lueking, A. D., & Boehman, A. L. (2011). The deconvolution of the thermal, dilution, and chemical effects of exhaust gas recirculation (EGR) on the reactivity of engine and flame soot. Combustion and Flame, 158(9), 1696-1704. doi:10.1016/j.combustflame.2011.02.006Ladommatos, N., Abdelhalim, S. M., Zhao, H., & Hu., Z. (1998). Effects of EGR on Heat Release in Diesel Combustion. SAE Technical Paper Series. doi:10.4271/980184Li, T., Wu, D., & Xu, M. (2013). Thermodynamic analysis of EGR effects on the first and second law efficiencies of a boosted spark-ignited direct-injection gasoline engine. Energy Conversion and Management, 70, 130-138. doi:10.1016/j.enconman.2013.03.001Roy, M. M., Tomita, E., Kawahara, N., Harada, Y., & Sakane, A. (2011). Comparison of performance and emissions of a supercharged dual-fuel engine fueled by hydrogen and hydrogen-containing gaseous fuels. International Journal of Hydrogen Energy, 36(12), 7339-7352. doi:10.1016/j.ijhydene.2011.03.070Wang, Zhang, Wang, Han, & Chen. (2019). Numerical Simulation of Knock Combustion in a Downsizing Turbocharged Gasoline Direct Injection Engine. Applied Sciences, 9(19), 4133. doi:10.3390/app9194133Caton, J. A. (2012). The thermodynamic characteristics of high efficiency, internal-combustion engines. Energy Conversion and Management, 58, 84-93. doi:10.1016/j.enconman.2012.01.005Su, J., Xu, M., Li, T., Gao, Y., & Wang, J. (2014). Combined effects of cooled EGR and a higher geometric compression ratio on thermal efficiency improvement of a downsized boosted spark-ignition direct-injection engine. Energy Conversion and Management, 78, 65-73. doi:10.1016/j.enconman.2013.10.041Gu, X., Huang, Z., Cai, J., Gong, J., Wu, X., & Lee, C. (2012). Emission characteristics of a spark-ignition engine fuelled with gasoline-n-butanol blends in combination with EGR. Fuel, 93, 611-617. doi:10.1016/j.fuel.2011.11.040Galloni, E. (2009). Analyses about parameters that affect cyclic variation in a spark ignition engine. Applied Thermal Engineering, 29(5-6), 1131-1137. doi:10.1016/j.applthermaleng.2008.06.001Bermúdez, V., Luján, J. M., Climent, H., & Campos, D. (2015). Assessment of pollutants emission and aftertreatment efficiency in a GTDi engine including cooled LP-EGR system under different steady-state operating conditions. Applied Energy, 158, 459-473. doi:10.1016/j.apenergy.2015.08.071Park, C., Kim, S., Kim, H., & Moriyoshi, Y. (2012). Stratified lean combustion characteristics of a spray-guided combustion system in a gasoline direct injection engine. Energy, 41(1), 401-407. doi:10.1016/j.energy.2012.02.060Galindo, J., Navarro, R., Tarí, D., & Moya, F. (2020). Development of an experimental test bench and a psychrometric model for assessing condensation on a low-pressure exhaust gas recirculation cooler. International Journal of Engine Research, 22(5), 1540-1550. doi:10.1177/1468087420909735Luján, J. M., Dolz, V., Monsalve-Serrano, J., & Bernal Maldonado, M. A. (2019). High-pressure exhaust gas recirculation line condensation model of an internal combustion diesel engine operating at cold conditions. International Journal of Engine Research, 22(2), 407-416. doi:10.1177/1468087419868026Boccardi, S., Catapano, F., Costa, M., Sementa, P., Sorge, U., & Vaglieco, B. M. (2016). Optimization of a GDI engine operation in the absence of knocking through numerical 1D and 3D modeling. Advances in Engineering Software, 95, 38-50. doi:10.1016/j.advengsoft.2016.01.023Pla, B., De La Morena, J., Bares, P., & Jiménez, I. (2020). Knock Analysis in the Crank Angle Domain for Low-Knocking Cycles Detection. SAE Technical Paper Series. doi:10.4271/2020-01-0549Serrano, J., Climent, H., Navarro, R., & González-Domínguez, D. (2020). Methodology to Standardize and Improve the Calibration Process of a 1D Model of a GTDI Engine. SAE Technical Paper Series. doi:10.4271/2020-01-1008Nishiyama, A., Le, M. K., Furui, T., & Ikeda, Y. (2019). The Relationship between In-Cylinder Flow-Field near Spark Plug Areas, the Spark Behavior, and the Combustion Performance inside an Optical S.I. Engine. Applied Sciences, 9(8), 1545. doi:10.3390/app908154

Exploring the impact of ketogenic diet on multiple sclerosis: obesity, anxiety, depression, and the glutamate system

Multiple sclerosis (MS) is a neurodegenerative disorder. Individuals with MS frequently present symptoms such as functional disability, obesity, and anxiety and depression. Axonal demyelination can be observed and implies alterations in mitochondrial activity and increased inflammation associated with disruptions in glutamate neurotransmitter activity. In this context, the ketogenic diet (KD), which promotes the production of ketone bodies in the blood [mainly β-hydroxybutyrate (βHB)], is a non-pharmacological therapeutic alternative that has shown promising results in peripheral obesity reduction and central inflammation reduction. However, the association of this type of diet with emotional symptoms through the modulation of glutamate activity in MS individuals remains unknown.AimTo provide an update on the topic and discuss the potential impact of KD on anxiety and depression through the modulation of glutamate activity in subjects with MS.DiscussionThe main findings suggest that the KD, as a source of ketone bodies in the blood, improves glutamate activity by reducing obesity, which is associated with insulin resistance and dyslipidemia, promoting central inflammation (particularly through an increase in interleukins IL-1β, IL-6, and IL-17). This improvement would imply a decrease in extrasynaptic glutamate activity, which has been linked to functional disability and the presence of emotional disorders such as anxiety and depression

Customised pressure profiles of made-to-measure sports compression garments

The purpose of this study was to make made-to-measure compression garments that elicit pressures within and below clinical standards. The study also examined whether pressures and gradients can be replicated within and between participants’ legs, and between separate compression garment conditions. Ten males volunteered to participate. Based on three-dimensional scans of the participants’ lower body, three different made-to-measure garments were manufactured: control, symmetrical and asymmetrical. Garment pressures were assessed from the malleolus to the gluteal fold using a pressure monitoring device. A root mean squared difference analysis was used to calculate the in vivo linear graduation parameters. Linear regression showed that peak pressure at the ankle in the left and right leg were: control garment, 13.5 ± 2.3 and 12.9 ± 2.6; asymmetrical garment, 12.7 ± 2.5 and 26.3 ± 3.4; symmetrical garment, 27.7 ± 2.2 and 27.5 ± 1.6 (all mmHg, mean ± standard deviation). Pressure reduction from the ankle to the gluteal fold in the left and right leg were: control, 8.9 ± 3.5 and 7.4 ± 3.0; asymmetrical, 7.8 ± 3.9 and 21.9 ± 3.2; symmetrical, 25.0 ± 4.1 and 22.3 ± 3.6 (all mmHg, mean ± standard deviation). Made-to-measure compression garments can be made to elicit pressures within and below clinical standards, and to elicit equivalent pressures and gradients in different participants

Y tú ¿de dónde vienes? |Blog de denuncia sobre el exilio de los jóvenes españoles

Treball Final de Grau en Periodisme. Codi: PE0932. Curs acadèmic 2013-201

Cost-Effectiveness of Upper Extremity Dry Needling in Chronic Stroke

Introduction: Dry needling is a non-pharmacological approach that has proven to be effective in different neurological conditions. Objective: The aim of this study was to evaluate the cost-effectiveness of a single dry needling session in patients with chronic stroke. Methods: A cost-effectiveness analysis was performed based on a randomized controlled clinical trial. The results obtained from the values of the EuroQol-5D questionnaire and the Modified Modified Ashworth Scale were processed in order to obtain the percentage of treatment responders and the quality-adjusted life years (QALYs) for each alternative. The cost analysis was that of the hospital, clinic, or health center, including the equipment and physiotherapist. The cost per respondent and the incremental cost-effectiveness ratio of each alternative were assessed. Results: Twenty-three patients with stroke were selected. The cost of DN treatment was EUR 14.96, and the data analysis showed a favorable cost-effectiveness ratio of both EUR/QALY and EUR/responder for IG, although the sensitivity analysis using limit values did not confirm the dominance (higher effectiveness with less cost) of the dry needling over the sham dry needling. Conclusions: Dry needling is an affordable alternative with good results in the cost-effectiveness analysis—both immediately, and after two weeks of treatment—compared to sham dry needling in persons with chronic stroke

Muscle Function Differences between Patients with Bulbar and Spinal Onset Amyotrophic Lateral Sclerosis. Does It Depend on Peripheral Glucose?

Background: One of the pathogenic mechanisms of ALS disease is perturbed energy metabolism particularly glucose metabolism. Given the substantial difference in the severity and the prognosis of the disease, depending on whether it has a bulbar or spinal onset, the aim of the study was to determine metabolic differences between both types of ALS, as well as the possible relationship with muscle function. Materials and Methods: A descriptive, analytical, quantitative, and transversal study was carried out in hospitals and Primary Care centers in the region of Valencia, Spain. Fasting glucose and alkaline phosphatase (AP) levels in venous blood, muscle percentage, fat percentage, muscle strength (MRC scale), and functional capacity (Barthel Index) were measured in 31 patients diagnosed with ALS (20 with spinal onset ALS and 11 with bulbar onset ALS). A healthy control of 29 people was included. Results: No significant differences were observed in blood AP and glucose levels between spinal onset and bulbar onset ALS patients. However, a significant positive correlation was observed between the mean values of both substances in patients with spinal onset ALS. Moreover, a lower percentage of muscle mass and a higher percentage of fat mass were also seen in spinal ALS patients, who also presented lower muscle strength and lower functional capacity. Conclusion: The results of this study seem to point to a possible difference in the peripheral use of glucose between patients with bulbar onset ALS and spinal onset ALS, who appear to have possible insulin resistance. These metabolic differences could explain the lower muscle percentage and lower muscular function in spinal onset ALS patients, although further studies are required

Intrarenal venous flow in cardiorenal syndrome : a shining light into the darkness

The aim of this case report is to assess the potential role of intrarenal Doppler ultrasonography as a non-invasive method to evaluate intrarenal venous flow (IRVF) in acute heart failure (AHF) and concomitant renal dysfunction. We report a case of an 81-year-old woman with valvular heart disease (previous mitral valve replacement) that presented with acutely decompensated heart failure and concomitant worsening renal function (WRF). In addition to complete physical examination, laboratory analysis, and echocardiography, IRVF was assessed at baseline and 48 h after the administration of diuretic treatment. At admission, physical examination and echocardiography revealed signs of intravascular congestion (jugular venous distension and severely dilated inferior vena cava). In addition, a significant increase in serum creatinine from 1.23 to 1.81 mg/dL was noted without signs of hypoperfusion at clinical evaluation. At baseline, intrarenal Doppler ultrasonography showed a monophasic IRVF pattern indicating a severely elevated interstitial renal pressure. After aggressive decongestion, a dynamic behaviour was found in IRVF changing from monophasic to biphasic pattern in parallel with an improvement in clinical parameters and renal function (serum creatinine changed from 1.81 to 1.44 mg/dL). In this case of a patient with AHF and WRF, IRVF changed after aggressive decongestion in agreement with clinical evolution. According to these findings, this technique could provide valuable information for identifying patients with a 'congestion kidney failure' phenotype. Further studies are needed confirming this observation and evaluating the potential role of this technique for guiding decongestive therapy in patients with AHF and WRF