3,232 research outputs found

    Hopf measuring comonoids and enrichment

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    We study the existence of universal measuring comonoids P(A,B)P(A,B) for a pair of monoids AA, BB in a braided monoidal closed category, and the associated enrichment of a category of monoids over the monoidal category of comonoids. In symmetric categories, we show that if AA is a bimonoid and BB is a commutative monoid, then P(A,B)P(A,B) is a bimonoid; in addition, if AA is a cocommutative Hopf monoid then P(A,B)P(A,B) always is Hopf. If AA is a Hopf monoid, not necessarily cocommutative, then P(A,B)P(A,B) is Hopf if the fundamental theorem of comodules holds; to prove this we give an alternative description of the dualizable P(A,B)P(A,B)-comodules and use the theory of Hopf (co)monads. We explore the examples of universal measuring comonoids in vector spaces and graded spaces.Comment: 30 pages. Version 2: re-arrangement of material; expansion of previous section 6, splitting into current sections 6,7,8; fix of graded algebras example, section 11; appendix removed; other minor fixes and edit

    Routines, Time Dedication and Habit Changes in Spanish Homes during the COVID-19 Lockdown. A Large Cross-Sectional Survey

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    Many countries chose to establish social distancing as lockdowns after the COVID-19 outbreak. Households had to adapt their day-to-day lifestyles to new circumstances, affecting routines and time dedication to tasks. This national study was carried out to find out how the confinement by COVID-19 affected Spanish households on the perceived habit changes during this period, in relation to their socio-demographic characteristics and household composition. An online questionnaire was launched during the COVID-19 lockdown, from 30 April to 22 June 2020. Descriptive statistics were analyzed, stratified by gender, on time dedication, routine, home leaving, and habit change variables. Chi-square tests were used to explore the relations of significance with socio-demographic characteristics and home composition. All contrast analyses were performed for a 95% confidence level (significance considered for p < 0.05). In total, 1673 respondents participated from different age groups, educational level, employment status and household composition. Sixty percent of respondents maintained their routines. A third tried to establish a new one, being related to women, young people, not a university student, and living with others, including minors. Regarding dedication to tasks, adults aged 35-54 years, with more cohabitants, especially women, devoted themselves intensively to the home or to care, while those under 35 were dedicated more to rest, leisure, television or reading. People with university studies were more related to teleworking. The frequency of going outside was related to gender, age, educational level and living with elders, specifically for grocery shopping and taking out garbage. Changes in habits, routines and time dedication in confinement were strongly linked to the sociodemographic and coexistence conditions in Spanish homes. The greatest impacts were suffered by women, people with children, and adults between 35-54 years of age, especially on care and domestic chores.This research was funded by Consejo Superior de Investigaciones Científicas (CSIC), grant number 202060E225, entitled: “Proyecto sobre confinamiento social (COVID-19), vivienda y habitabilidad [COVID-HAB]”.S

    Additive Ensemble Neural Network with Constrained Weighted Quantile Loss for Probabilistic Electric-Load Forecasting

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    This work proposes a quantile regression neural network based on a novel constrained weighted quantile loss (CWQLoss) and its application to probabilistic short and medium-term electric-load forecasting of special interest for smart grids operations. The method allows any point forecast neural network based on a multivariate multi-output regression model to be expanded to become a quantile regression model. CWQLoss extends the pinball loss to more than one quantile by creating a weighted average for all predictions in the forecast window and across all quantiles. The pinball loss for each quantile is evaluated separately. The proposed method imposes additional constraints on the quantile values and their associated weights. It is shown that these restrictions are important to have a stable and efficient model. Quantile weights are learned end-to-end by gradient descent along with the network weights. The proposed model achieves two objectives: (a) produce probabilistic (quantile and interval) forecasts with an associated probability for the predicted target values. (b) generate point forecasts by adopting the forecast for the median (0.5 quantiles). We provide specific metrics for point and probabilistic forecasts to evaluate the results considering both objectives. A comprehensive comparison is performed between a selection of classic and advanced forecasting models with the proposed quantile forecasting model. We consider different scenarios for the duration of the forecast window (1 h, 1-day, 1-week, and 1-month), with the proposed model achieving the best results in almost all scenarios. Additionally, we show that the proposed method obtains the best results when an additive ensemble neural network is used as the base model. The experimental results are drawn from real loads of a medium-sized city in Spain.This research was funded with grant RTI2018-098958-B-I00 from Proyectos de I+D+i «Retos investigación», Programa Estatal de I+D+i Orientada a los Retos de la Sociedad, Plan Estatal de Investigación Científica, Técnica y de Innovación 2017-2020. Spanish Ministry for Science, Innovation and Universities; the Agencia Estatal de Investigación (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER)

    The keys to avoid undesired structural defects in nanotubular TiO2 films prepared by electrochemical anodization

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    The effect of the viscosity of solvent mixtures based in ethylene glycol on the formation of undesired structural defects (nanograss) during the electrochemical synthesis of nanotubular TiO2 structures is analyzed. High quality nanotubular TiO2 films can be achieved by diminishing the viscosity of ethylene glycol-based media by increasing the water content as well as using ethanol as additive. High surface tension of water also promotes the film fracture and accumulation of agglomerates on the film surface. A previously unexplored one-step strategy consisting in the addition of ethanol to ethylene glycol/water mixtures as an alternative anodization medium is proposed. The evidence obtained indicate that this medium allows obtaining nanotubular TiO2 films with superior structural stability against capillary forces during the film drying, avoiding the use of time consuming post-treatments such as the commonly employed supercritical CO2 dehydrating, improving the properties of the obtained nanomaterials.Fil: Broens, Martin Ignacio. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Ramos Cervantes, Wilkendry. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Oyarzún Jerez, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Universidad Tecnologica Metropolitana (utem); ChileFil: Lopez Teijelo, Manuel. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Linarez Pérez, Omar Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

    Simple and rapid one-step electrochemical synthesis of nanogranular Cu2O films

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    In the present work, we report a simple experimental strategy for the one-step electrochemical synthesis of nanogranular Cu2O films by copper anodization in fluoride-containing ethylene glycol media. Microscopic exploration using field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM), shows the formation of spherical shape grains with sizes ranging from 20 to 40 nm. Raman and X-Ray Photoemission Spectroscopy (XPS) results indicate that only CuI oxide is obtained. A band gap energy Eg=2.01 eV is estimated from UV–vis reflectance spectroscopy indicating that an indirect transition mechanism between semiconductor bands takes place. These evidences indicate that the present synthesis of nanogranular Cu2O films is a promising method for obtaining improved properties of materials for the design of photoelectronic devices.Fil: Oyarzún Jerez, Diego Patricio. Universidad Andrés Bello; ChileFil: Broens, Martin Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Linarez Pérez, Omar Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Lopez Teijelo, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Islas, Rafael. Universidad Andrés Bello; ChileFil: Arratia-Perez, Ramiro. Universidad Andrés Bello; Chil

    MaLECoN: un nuevo material híbrido laminado fibra-metal para construcción naval.

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    Existe la necesidad perentoria de nuevos materiales para construcción naval que sean capaces de satisfacerlos requerimientos de diseño y fabricación de estructuras más ligeras, a la vez que resistentes, que permitan velocidades de desplazamiento más elevadas y menores consumos energéticos. El acero presenta una serie de limitaciones que dificultan la mejora continuada en la línea marcada para la fabricación de estructuras ligeras, resistentes y seguras. Los materiales compuestos son livianos y resistentes, pero los sistemas de fabricación son costosos y precisan de más mano de obra especializada; por otra parte, son muy sensibles al daño por impacto y pueden presentar problemas de degradación de sus propiedades mecánicas debido a la absorción de agua. Los materiales híbridos laminados fibra-metal combinan la elevada resistencia al impacto y la durabilidad, junto a la versatilidad en los procesos productivos propios de los materiales metálicos, con la resistencia y rigidez específicas en la dirección de las fibras, así como un buen comportamiento a fatiga, característica de los materiales compuestos. El material híbrido multicapas está formado por láminas metálicas alternando con otras de material compuesto y de adhesivo estructural, consiguiéndose prestaciones en servicio mejoradas. Este material ha sido patentado en la Oficina Española de Patentes y Marcas, junto con su procedimiento de fabricación. La extensión internacional de la patente a más de treinta países ha sido ya presentada y está siguiendo el procedimiento de concesión

    Urinary cyclophilin A as marker of tubular cell death and kidney injury

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    Background: Despite the term acute kidney injury (AKI), clinical biomarkers for AKI re-flect function rather than injury and independent markers of injury are needed. Tubular cell death, including necroptotic cell death, is a key feature of AKI. Cyclophilin A (CypA) is an intracellular protein that has been reported to be released during necroptosis. We have now explored CypA as a potential marker for kidney injury in cultured tubular cells and in clinical settings of ischemia-reperfusion injury (IRI), characterized by limitations of current diagnostic criteria for AKI. Meth-ods: CypA was analyzed in cultured human and murine proximal tubular epithelial cells exposed to chemical hypoxia, hypoxia/reoxygenation (H/R) or other cell death (apoptosis, necroptosis, fer-roptosis) inducers. Urinary levels of CypA (uCypA) were analyzed in patients after nephron sparing surgery (NSS) in which the contralateral kidney is not disturbed and kidney grafts with initial function. Results: Intracellular CypA remained unchanged while supernatant CypA increased in parallel to cell death induction. uCypA levels were higher in NSS patients with renal artery clamping (that is, with NSS-IRI) than in no clamping (NSS-no IRI), and in kidney transplantation (KT) recipients (KT-IRI) even in the presence of preserved or improving kidney function, while this was not the case for urinary Neutrophil gelatinase-associated lipocalin (NGAL). Furthermore, higher uCypA levels in NSS patients were associated with longer surgery duration and the incidence of AKI increased from 10% when using serum creatinine (sCr) or urinary output criteria to 36% when using high uCypA levels in NNS clamping patients. Conclusions: CypA is released by kidney tubular cells during different forms of cell death, and uCypA increased during IRI-induced clinical kidney injury independently from kidney function parameters. Thus, uCypA is a potential bi-omarker of kidney injury, which is independent from decreased kidney functionResearch by the authors was funded by FIS/ FEDER funds (PI17/00257, PI18/01386, PI19/00588, PI19/00815, DTS18/00032, ERA-PerMed-JTC2018 (KIDNEY ATTACK AC18/00064 and PERSTIGAN AC18/00071, ISCIII-RETIC REDinREN RD016/0009), Sociedad Española de Nefrología, FRIAT, Comunidad de Madrid en Biomedicina B2017/BMD-3686 CIFRA2-CM. Salary support: ISCIII Miguel Servet to A.B.S., MICIN Ramon y Cajal to M.D.S.-N., REDinREN RD016/0009 to M.F.-B.,SENEFRO to D.M.-S. and Consejería de Educación, Juventud y Deporte (Comunidad de Madrid/FSE) to A.M.L.-
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