Fluid dynamics of mixing in the tanks of small vanadium redox flow batteries: Insights from order-of-magnitude estimates and transient two-dimensional simulations

This paper investigates the fluid dynamics of mixing in the tanks of small-scale vanadium redox flow batteries. These systems use two redox pairs dissolved in separate electrolytes to convert electrical energy into chemical energy, a process that can be reversed in an efficient way to restore the initial electrical energy with negligible chemical losses. After flowing through the electrochemical cell, the electrolytes are stored in separate tanks, where they discharge as submerged jets with small temperature and composition changes compared to the electrolyte already present in the tanks. The subsequent mixing process is critical for battery performance, as imperfect mixing tends to reduce the energy capacity and may lead to asymmetric battery operation. The analysis starts using order-of-magnitude estimates to determine the conditions under which the mixing process is dominated by momentum or buoyancy. Transient two-dimensional simulations illustrate the different flow regimes that emerge in the tanks under laminar flow conditions. The results show that, contrary to the common assumption, the electrolytes do not mix well in the tanks. In the presence of high-momentum -- and, specially, positively buoyant -- jets, a significant fraction of the electrolyte remains unmixed and unreacted for long periods, thus reducing the energy capacity. The results also show that the availability of reliable electrolyte properties is crucial for the accuracy of the numerical simulations, as, under the mixed convection conditions that typically prevail in vanadium redox flow batteries, small density variations can significantly impact the long-term mixing of the electrolytes. In particular, in momentum-dominated flows the cumulative effect of density changes over time eventually leads to flow instabilities that significantly promote mixing; therefore, they should be taken into account in future studies

The Impact of Sleep Quality on Mood Status and Quality of Life in Patients with Alopecia Areata: A Comparative Study

Alopecia Areata (AA) is a chronic condition which has been associated with poor quality of life and mood status disturbances. The aim of this study is to compare the sleep quality between AA patients and controls, and to analyze the impact of poor sleep quality on patients with AA regarding mood status disturbances, quality of life and sexuality. A cross-sectional study including patients suffering from mild-to-severe AA and sex- and age-matched healthy controls was performed. Socio-demographic and clinical variables, sleep quality, quality of life, sexual disfunction, anxiety, depression and personality were collected using validated questionnaires. A total of 120 participants (60 patients and 60 controls) were included. Patients with AA showed worse sleep scores than controls (p = 0.003), as well as higher rates of anxiety and depression (p < 0.05). After a multivariate analysis, a worse sleep quality was found to be linked to anxiety, depression, a poorer quality of life and a type D personality score independently of the disease severity. In light of the results, patients with AA have a worse sleep quality than healthy controls. A poor sleep quality is associated with anxiety, depression and a worse quality of life, therefore being a general marker of a poor quality of life. Screening for sleep disturbances in specialized units could be useful to detect patients who could benefit from additional psychological support

Ayudar activando. Agentes de empleo ante las ambivalencias de la “Ocupación Plena”

La “recuperación económica” de los efectos de la crisis de 2007 en España se hubo de operar mediante la intensificación del trabajo y la precarización del empleo, y en ambos procesos tuvieron un papel fundamental las políticas de gestión del desempleo, determinadas por la reforma laboral de 2012 y la Nueva ley de Empleo de 2015. Reformas orientadas a la activación de las personas desocupadas mediante el intercambio de ayuda a cambio de empleabilidad. Son muchos los estudios que vinculan estas políticas a una suerte de “mercantilización neoliberal de la ayuda social”, pero menos los que tratan de entenderlas a partir de los propios esquemas teóricos y dispositivos prácticos de la teoría del “pleno empleo” keynesiana, formalmente opuesta al neoliberalismo. Así, es posible entender cómo los servicios públicos de empleo, cuya legitimidad social deriva de su aparente función de tutela del desempleado, se orientan hoy, por el contrario, a su activación. Y el trabajo de las y los agentes de empleo se revela como un analizador privilegiado para mostrar cómo se gestionan estas contradicciones en su práctica cotidiana

Quality of Life and Mood Status Disturbances in Cohabitants of Patients with Alopecia Areata: A Cross-Sectional Study in a Spanish Population

A poor quality of life has been described in patients suffering from Alopecia Areata (AA). However, there is little evidence on how AA can impact on those living with patients. The aim of this study is to analyze the impact of AA on a cohabitant’s quality-of-life, mood status disturbances and sexual satisfaction. This is a cross-sectional study of AA patients and their cohabitants. Sociodemographic variables and disease severity, the quality of life, mood status disturbances and sexual dysfunction were collected using validated questionnaires. Eighty-four subjects were included in the study: 42 AA patients and 42 cohabitants. A poor quality of life and worse disease control in the patients were associated with a poorer quality of life of the family, higher scores of anxiety and depression, and the lower sexual satisfaction of cohabitants (p < 0.05). Anxiety and depression in patients were associated with worse family quality of life, higher rates of anxiety and less sexual satisfaction in cohabitants (p < 0.05). To conclude, AA seems to have an impact on the quality of life of cohabitants, leading to increased rates of anxiety, depression, a poorer quality of life, and reduced sexual satisfaction. In light of the results, a global approach for AA patients, including the care of the people who live with them, should be implemented

Assessment of bio-ionic liquids as promising solvents in industrial separation processes: Computational screening using COSMO-RS method

The use of organic solvents in the chemical industry for gas-liquid absorption or liquid-liquid extraction operations is still unavoidable. The search of “greener” solvents to replace fossil-based counterparts is a challenge for the scientific community. Biocompatible ionic liquids (bio-ILs) emerged as a sustainable approach for the development of greener processes. In this work, bio-ILs based on choline as common cation are evaluated as promising solvents in typical industrial separation processes such as gas absorption (refrigerants, CO2, H2S, NH3, or acetone) and liquid-liquid extraction (hydrocarbon separations, denitrogenation, desulfurization, and recovery of value-added compounds and/or contaminants from aqueous streams) by means of COSMO-RS method. Some bio-ILs show competitive behavior compared to the benchmark common ILs solvents for all the solutes evaluated. None of the solvents evaluated is predicted to form two liquid phases in aqueous solutions, so future work should be conducted on finding hydrophobic bio-ILs to perform these separations. On the other hand, bio-ILs in hydrocarbon separations by means of liquid-liquid extraction show competitive results in terms of selectivities (benzoate-based) and partition coefficients (bicarbonate-based) compared to benchmark sulfolane and common ILs previously testedThe authors are grateful to Comunidad de Madrid (project SUSTEC P2018/EMT-4348) and Ministerio de Economía y Competitividad of Spain (project CTQ2017-89441-R) for its financial support and Centro de Computación Científica de la Universidad Autónoma de Madrid (CCC) for its computational resources. Rubén Santiago thanks Ministerio Universidades for his Margarita Salas contract (CA1/RSUE/2021-00585

Validación del SPPB (Short Physical Performance Battery) como predictor de sarcopenia en mujeres adultas mayores de la Comunidades Religiosas Hijas de la Caridad San Vicente de Paul y Vicentinas, de las ciudades de Quito y Riobamba, entre los meses de octubre a diciembre del 2014

Los cambios ambientales, culturales y socio-económicos actuales nos conducen progresivamente a un envejecimiento progresivo, obligándonos a adoptar nuevos instrumentos de valoración capaces de describir, diagnosticar, controlar y asignar recursos para un segmento poblacional creciente y generalmente carente de atenciones. La sarcopenia constituye un problema de alta prevalencia en adultos mayores generando un alto impacto socio-económico. La poca disponibilidad de métodos que permitan su diagnóstico, ha motivado la búsqueda e implementación de una herramienta diagnostica alternativa, que fue validada en la población de religiosas de las comunidades Hijas De La Caridad y Vicentinas de las ciudades de Quito y Riobamba entre los meses de octubre a diciembre del 2014. Se estudiaron 76 pacientes, de acuerdo a los criterios de inclusión. Nuestro propósito fue la validación de la Short Physical Performance Battery (SPPB) como predictor de sarcopenia en mujeres adultas mayores de las comunidades religiosas, utilizando como Gold Estandar la Bioimpedancia eléctrica (BIA). Para este fin, utilizamos el formulario de atención a adulto mayor 057, además de la aplicación del SPPB de manera individual y la medición mediante BIA. Los datos obtenidos fueron analizados utilizando los programas informáticos Statistical Package for Social Sciences Inc. versión 23.0 para Windows XP (SPSS), Microsoft Excel 2010 con licencia de la PUCE y el programa Epidat versión 3.0. Los resultados obtenidos nos permite concluir que el SPPB identifica precozmente estados de sarcopenia leve, incluso por sobre la BIA, que únicamente establece estados moderados y graves de la misma, brindándonos una herramienta de fácil replicación con bajo costo y sin riesgo para el paciente, facilitando intervenciones oportunas, que eviten la progresión de la enfermedad, como se pudo evidenciar en los centros de cuidado gerontológico de las religiosas, en los que la atención individualizada y permanente brindan las condiciones ideales para un envejecimiento saludable, optimizando los recursos económicos y médicos a su alcance

Star-formation histories of local luminous infrared galaxies

We present the analysis of the integrated spectral energy distribution (SED) from the ultraviolet (UV) to the far-infrared and H$\alpha$ of a sample of 29 local systems and individual galaxies with infrared (IR) luminosities between 10^11 Lsun and 10^11.8 Lsun. We have combined new narrow-band H$\alpha$+[NII] and broad-band g, r optical imaging taken with the Nordic Optical Telescope (NOT), with archival GALEX, 2MASS, Spitzer, and Herschel data. The SEDs (photometry and integrated H$\alpha$ flux) have been fitted with a modified version of the MAGPHYS code using stellar population synthesis models for the UV-near-IR range and thermal emission models for the IR emission taking into account the energy balance between the absorbed and re-emitted radiation. From the SED fits we derive the star-formation histories (SFH) of these galaxies. For nearly half of them the star-formation rate appears to be approximately constant during the last few Gyrs. In the other half, the current star-formation rate seems to be enhanced by a factor of 3-20 with respect to that occured ~1 Gyr ago. Objects with constant SFH tend to be more massive than starbursts and they are compatible with the expected properties of a main-sequence (M-S) galaxy. Likewise, the derived SFHs show that all our objects were M-S galaxies ~1 Gyr ago with stellar masses between 10^10.1 and 10^11.5 Msun. We also derived from our fits the average extinction (A_v=0.6-3 mag) and the polycyclic aromatic hydrocarbons (PAH) luminosity to L(IR) ratio (0.03-0.16). We combined the A_v with the total IR and H$\alpha$ luminosities into a diagram which can be used to identify objects with rapidly changing (increasing or decreasing) SFR during the last 100 Myr.Comment: 16 pages + online material, accepted for publication in A&

Impact of the COVID-19 Pandemic on the Diagnosis and Prognosis of Melanoma

Background: Early detection of melanoma is one of the main diagnostic goals of dermatologists worldwide, due to the increasing incidence of the disease in our environment. However, the irruption of the SARS-CoV-2 pandemic has posed a challenge to global healthcare, forcing systems to focus their resources on the fight against COVID-19. Methods: Retrospective cohort study. The exposed cohort were patients diagnosed with melanoma in the year after the general confinement in Spain (15 March 2020) and the unexposed cohort were patients with melanoma diagnosed in the previous year. Results: 130 patients were included. No differences were observed between demographic characteristics in both cohorts. The mean Breslow of melanoma before the onset of the pandemic was 1.08, increasing to 2.65 in the year after the onset of the pandemic (p < 0.001). On the other hand, the percentage of melanomas in situ decreased from 38.96% to 16.98% in the year after the declaration of the state of alarm in Spain. Conclusions: The SARS-CoV-2 outbreak has led to a reduction in the early diagnosis of melanoma, with an increase in invasive melanomas with poor prognosis histological factors. This could lead to an increase in melanoma-related mortality in the coming years in our environment

Spatial valuation of forests' enviromental assets: an application to Andalusian Silvopastoral farms

We develop a model that estimates spatially allocated environmental asset values for the simultaneous provision of seven ecosystem services. We examine the effect of heterogeneous spatial and economic factors on asset figures, and identify potential forestry abandonment problems when continuing with forestry activity becomes unprofitable for the landowner. Our results show a relevant spatial variability according to forest species distribution and structure. We examine potential trade-offs among silvopastoral provisioning services, water, and carbon sequestration services. Results forecast the abandonment of forestry activity and quantify the significant impact of discount rates and prices on asset values