Redes Bayesianas para detección de roles de equipos en aprendizaje colaborativo soportado por computadoras

El trabajo colaborativo soportado por computadoras permite a los estudiantes que se encuentran en lugares remotos trabajar de manera conjunta en el mismo entorno virtual y permite la comunicación de ideas e información entre los integrantes del grupo. Sin embargo, como no todos los estudiantes son iguales, es importante estudiar las características de éstos para construir grupos de trabajo más productivos. La teoría de roles de equipo posibilita obtener buen desempeño en los equipos de trabajo considerando habilidades individuales, combinando las falencias de cada rol con las fortalezas de los otros. Generalmente, las personas tienen que completar extensos cuestionarios para poder determinar sus roles de equipo. En este trabajo, se propone un método alternativo para realizar esta detección a través de un sistema de aprendizaje colaborativo y a partir de la utilización de la técnica de Redes Bayesianas.Computer-supported collaborative learning allows students who are in different places to work together in the same virtual space, and supports the communication of ideas and information among learners. However, as not all students are identical, it is important to study users' characteristics to build more productive teams. Team Roles Theory allows obtaining very good team performance taking into account individual skills, combining the weaknesses of each role with the strengths of others. Originally, people have to complete extensive questionnaires to determine their team role. In this work we propose an alternative method to make this detection through a collaborative learning system and by using a Bayesian Network.Fil: Balmaceda, José María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto Superior de Ingeniería del Software. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto Superior de Ingeniería del Software; ArgentinaFil: Schiaffino, Silvia Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto Superior de Ingeniería del Software. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto Superior de Ingeniería del Software; ArgentinaFil: Godoy, Daniela Lis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto Superior de Ingeniería del Software. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto Superior de Ingeniería del Software; Argentin

Comparative Study of The Finishing Effects Imparted by Enzymatic Treatments Applied to Undyed and Dyed Wool Fabrics

The use of enzymes in the finishing of wool fabrics could be an alternative to the traditional finishing with chemicals. The main objective is to obtain some finishing processes that are more environment-friendly than the traditional ones. Recently, the research on the application of different types of enzymes has been intensified in order to achieve different finishing effects. Concretely, the proteases are one of the types of enzymes that have shown to be efficient to confer the wool a better behaviour regarding felting shrinkage. They also improve the handle and the drape of the fabrics. The effectiveness of the enzymatic treatment appreciably varies depending on the type of protease and the application conditions. The enzymatic treatment has shown to be effective to improve the softness, handle and drape of the fabrics, as well as to increase their pilling resistance when the treatment conditions are intense enough. However, these treatment conditions can produce excessive losses on mechanical properties. The effects caused by the enzymatic treatment present, in general, the same tendencies in undyed and dyed fabrics. Nevertheless, in some parameters, significant differences are observed. The enzymatic treatments may also produce small changes in the colour of the dyed fabrics. These changes in colour are mainly due to luminosity variations.Peer ReviewedPostprint (published version

Assessment of the molecular structure and spectroscopic properties of CF3-substituted sulfinylaniline derivatives

The presence of a perfluorinated functional group as a substituent of the aromatic ring in m- and o-trifluoromethylsulfinylaniline may provide conformational and vibrational properties of interest for the synthesis of compounds of pharmacological relevance, as it was observed for other N-sulfinylaniline derivatives previously reported. The air sensitive and highly reactive compounds under study were prepared by the reaction of the corresponding aniline derivatives and thionyl chloride. The liquid samples were characterized by FT IR, Raman and NMR (1H and 13C) spectroscopies and GC/MS spectrometry. The experimental spectra indicate the presence of a single conformer of syn geometry (syn of the C-N bond with respect to the S=O bond), in good agreement with results obtained by quantum chemical calculations derived from the Functional Density Theory. The stable conformation found as the global minimum of the potential energy surface was rationalized by considering intramolecular orbital interactions evinced by a Natural Bond Orbital (NBO) analysis and the quantum theory of Atoms In Molecules (AIM). Through this last approach, an intramolecular C-H⋅⋅⋅O interaction meeting the characteristics of an anti-hydrogen bond was found.Fil: Chemes, Doly María. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucumán. Unidad de Administración Territorial; ArgentinaFil: Lezama, José Osvaldo Guy. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Cutin, Edgardo Hugo. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; Argentina. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Robles, Norma Lis. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

Factores sociales de riesgo para la falta de cumplimiento terapéutico en pacientes con tuberculosis en Pontevedra

ResumenObjetivoConocer la prevalencia y caracteristicas de los factores sociales de riesgo (FSR) para la falta de cumplimiento terapeutico entre los enfermos de tuberculosis de Pontevedra.MetodosAnalisis descriptivo de los enfermos de tuberculosis con FSR diagnosticados entre 1996 y 2002. Se considero FSR la presencia de aislamiento social (alcoholismo, uso de drogas por via parenteral, presidiario, sin domicilio fijo-sin techo, inadaptacion social) o la inmigracion. Se calculo la prevalencia y la tendencia anual de los FSR, la situacion final de los pacientes y la influencia de la administracion directamente observada del tratamiento en la situacion final.ResultadosDe los 775 casos de TB, 156 pacientes (20,1%) tenian algun FSR, 86 pacientes presentaban alcoholismo, 41 eran usuarios de drogas por via parenteral, 24 eran inmigrantes, 14 no tenian domicilio fijo, 11 se consideraron con inadaptacion social y 10 eran presidiarios. La presencia de FSR entre los enfermos de tuberculosis no mostro una tendencia a aumentar o disminuir durante el periodo de estudio, excepto por el incremento de inmigrantes (χ2 para la tendencia lineal = 12,24; p = 0,005). La proporcion de pacientes con situacion final satisfactoria (curacion bacteriologica o tratamiento finalizado) fue significativamente mayor en el grupo de pacientes sin FSR (el 90,4 frente al 70,8%; p < 0,001). La administracion directamente observada del tratamiento a los pacientes con FSR no mejoro de manera significativa el porcentaje de enfermos con situacion final satisfactoria.ConclusionesLos pacientes con FSR tienen una mayor probabilidad de presentar una situacion final no satisfactoria. La presencia de FSR entre los enfermos con tuberculosis es baja en nuestro medio. Existe una incipiente tendencia al aumento de enfermos inmigrantes procedentes de paises con mayor prevalencia de tuberculosis, hecho que debe considerarse de cara a un mejor control de la enfermedad.AbstractObjectiveTo determine the prevalence and characteristics of social risk factors (SRF) for noncompliance with treatment in patients with tuberculosis (TB) in Pontevedra.MethodsWe performed a descriptive analysis of patients with TB and SRF diagnosed between 1996 and 2002. A patient was considered as having SRF if he or she was socially isolated (alcoholism, intravenous drug use, prison inmate, homelessness or social maladjustment) or was an immigrant. The prevalence, annual trend of SRF and patient outcomes were calculated. The influence of direct observation of treatment administration on the outcome of patients with SRF was also analyzed.ResultsOf 775 patients with TB, 156 (20.1%) had at least one SRF. Eighty-six patients were alcoholic, 41 were intravenous drug users, 24 were immigrants, 11 were homeless, 11 showed social maladjustment and 10 were prison inmates. The presence of SRF among TB patients showed no tendency to increase or decrease during the study period, except for the increasing number of immigrants (χ2 for lineal tendency = 12.24; p = 0.005). Final outcomes were significantly better in patients without SRF (90.4 vs 70.8% of satisfactory final outcomes; p < 0.001). Direct observation of treatment did not increase satisfactory outcomes in patients with SRF.ConclusionsPatients with TB and SRF have a significantly higher proportion of unsatisfactory final outcomes. The presence of SRF is relatively low in our environment. The number of immigrants from countries with a high prevalence of TB shows an incipient tendency to increase. This finding should be taken into account to achieve better control of the disease

A voltammetric e-tongue tool for the emulation of the sensorial analysis and the discrimination of vegetal milks

[EN] The relevance of plant-based food alternatives to dairy products, such as vegetable milks, has been growing in recent decades, and the development of systems capable of classifying and predicting the sensorial profile of such products is interesting. In this context, a methodology to perform the sensorial analysis of vegetable milks (oat, soya, rice, almond and tiger nut), based on 12 parameters, was validated. An electronic tongue based on the combination of eight metals with pulse voltammetry was also tested. The current intensity profiles are characteristic for each non-dairy milk type. Data were processed with qualitative (PCA, dendrogram) and quantitative (PLS) tools. The PCA statistical analysis showed that when using three first principal components, which covered 77% of variance, the eight samples can be differentiated, and the preparation method (artisanal milks or commercial) is one of the main differentiation factors, together with raw material type. The PLS statistical analysis allowed models to be created to predict all 12 sensorial parameters. The goodness of the predictions depends on the parameter being particularly accurate for the body, the granularity in the wall of glass and homogeneity of colour. The results strongly suggest the potential feasibility of using electronic tongues as systems for easy, rapid and effective sensorial assessments of vegetable milks. (C) 2018 Elsevier B.V. All rights reserved.The authors thank the financial support from the Spanish Government (Project MAT2015-64139-C4-1-R) and the Generalitat Valenciana (Project PROMETEOII/2014/047).Pascual, L.; Gras Romero, ML.; Vidal Brotons, DJ.; Alcañiz Fillol, M.; Martínez-Máñez, R.; Ros-Lis, JV. (2018). A voltammetric e-tongue tool for the emulation of the sensorial analysis and the discrimination of vegetal milks. Sensors and Actuators B Chemical. 270:231-238. https://doi.org/10.1016/j.snb.2018.04.151S23123827

Application of mesoporous silica materials for the immobilization of polyphenol oxidase

[EN] The ability of a number of mesoporous silica materials (SBA-15, SBA-3, and MCM-48) to immobilize polyphenol oxidase (PPO) at different pH has been tested. Pore size and volume are the structural characteristics with higher influence on the PPO immobilization. Mesoropous material SBA-15 adsorbs a larger quantity of PPO at pH 4.00 and offers an inhibition of enzymatic activity close the 50% in apple extracts.AEGB acknowledges support from the Swedish Research Council (Grant Number 621-2012-3375), the ARC Centre of Excellence for Nanoscale BioPhotonics (CE140100003), and an ARC Future Fellowship (FT150100342)Corell Escuin, P.; Garcia-Benett, A.; Ros-Lis, JV.; Argüelles Foix, AL.; Andrés Grau, AM. (2017). Application of mesoporous silica materials for the immobilization of polyphenol oxidase. Food Chemistry. 217:360-363. https://doi.org/10.1016/j.foodchem.2016.08.027S36036321

Full inhibition of enzymatic browning in the presence of thiol-functionalised silica nanomaterial

[EN] Darkening processed fruits and vegetables is caused mainly by enzymatic browning through polyphenol oxidase (PPO) action. Accordingly, we explored the potential of four silica-based materials (MCM-41 nanometric size, MCM-41 micrometric size, UVM-7 and aerosil), non-functionalised and functionalised with thiol groups, to inhibit PPO activity in the model system and apple juice. All materials showed relevant performance when immobilising and inhibiting PPO in model systems, and support topology is a main factor for enzyme immobilisation and inhibition. Thiol-containing silica UVM7-SH showed the greatest inactivation, and similar browning values to those obtained by acidification. The enzyme's kinetic parameters in the presence of UVM-7-SH suggested non-competitive inhibition, which indicated that the material interacted with the enzyme, but beyond the active centre. In real systems, UVM-7-SH completely inhibited enzymatic browning in apple juice (cv. Granny Smith and cv. Golden Delicious) up to 9 days after 5 min of contact.The authors thank the financial support obtained from the Spanish Government (Project MAT2015-64139-C4-1-R) and the Generalitat Valenciana (Project GVA/2014/13).Muñoz-Pina, S.; Ros-Lis, JV.; Argüelles Foix, AL.; Coll, C.; Martínez-Máñez, R.; Andrés Grau, AM. (2018). Full inhibition of enzymatic browning in the presence of thiol-functionalised silica nanomaterial. Food Chemistry. 241:199-205. https://doi.org/10.1016/j.foodchem.2017.08.059S19920524

Highly active hydrogenation catalysts based on Pd nanoparticles dispersed along hierarchical porous silica covered with polydopamine as interfacial glue

New catalysts based on Pd(0) nanoparticles (Pd NPs) on a bimodal porous silica of the UVM-7/polydopamine (PDA) support have been synthesized following two preparative strategies based on the sequential or joint incorporation of two components of the composite (Pd and PDA). We analyzed the role played by the PDA as 'interfacial glue' between the silica scaffold and the Pd NPs. The catalysts were tested for the hydrogenation of 4-nitrophenol using (NEt4)BH4 as the hydrogenating agent. In addition to the palladium content, the characterization of the catalysts at the micro and nanoscale has highlighted the importance of different parameters, such as the size and dispersion of the Pd NPs, as well as their accessibility to the substrate (greater or lesser depending on their entrapment level in the PDA) on the catalytic efficiency. Staged sequential synthesis has led to better catalytic results. The most active Pd(0) centers seem to be Pd NPs of less than 1 nm on the PDA surface. The efficiency of the catalysts obtained is superior to that of similar materials without PDA. A comprehensive comparison has been made with other catalysts based on Pd NPs in a wide variety of supports. The TOF values achieved are among the best described in the literature

A tetraazahydroxypyridinone derivative as inhibitor of apple juice enzymatic browning and oxidation

[EN] Enzymatic browning in fruits and vegetables can produce undesirable colour changes and adversely affect the taste, flavour, and nutritional value. This fact poses a challenge to the food industry to apply appropriate inhibitors to control enzymatic browning to maintain food quality. Accordingly, this study aims to evaluate the effect of small mazamacrocyclic compounds modified with a hydroxypyridinone similar to kojic acid on enzymatic browning, total polyphenols and antioxidant activity in apple juice. The results showed how these compounds interact with the tyrosinase enzyme in a complex interaction inhibiting its activity. The hydroxypyridinone attached to the macrocycle (I1) was crucial to induce the greatest inhibition, being the most powerful inhibitor. The kinetic studies of I1 reveal mixed-type inhibition over tyrosinase with an IC50 of 0.30 mM, which was much higher than the calculated IC50 for I2 and I3. Furthermore, I1 at a concentration of 2.25 mM, significantly reduced the enzymatic browning in fresh apple juice by more than 50% after 1 h under stirring. Also, it completely stops the decrease in the total phenolic content and delays loss of antioxidant capacity during the first 30 min.Grant RTI2018-100910-B-C44 funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe" and the Spanish Ministerio de Economia y Competitividad (Projects CTQ2016-78499C6-1-R, CTQ2017-90852-REDC, RED2018-102331-T, PID 2019110751RB-I00 and Unidad de Excelencia CEX2019-000919-M).Muñoz-Pina, S.; Duch-Calabuig, A.; Ros-Lis, JV.; Verdejo, B.; García-España, E.; Argüelles Foix, AL.; Andrés Grau, AM. (2022). A tetraazahydroxypyridinone derivative as inhibitor of apple juice enzymatic browning and oxidation. LWT - Food Science and Technology. 154:1-7. https://doi.org/10.1016/j.lwt.2021.1127781715

Bioactive compounds and enzymatic browning inhibition in cloudy apple juice by a new magnetic UVM-7-SH mesoporous material

[EN] Fruits and vegetables juices present a high supply of polyphenols, making them highly exposed to enzymatic browning. In this work, we report a novel magnetized mesoporous silica material (Fe3O4NPs-UVM-7) functionalised with thiol and amine groups and evaluate their effect on the enzymatic browning as well as the physicochemical properties (pH and degrees Brix), bioactive compounds (ascorbic acid, total phenolics, flavonoids, and flavonols) and the antioxidant capacity of cloudy apple juice. From the obtained results, the mesoporous silica material magnetized by 11 % (w/w) with magnetite and functionalized with thiol groups reduce by 70 % the enzymatic browning in apple juice. It did not affect the physicochemical parameters such as pH or total soluble solids with respect to freshly squeezed juice. In addition, the content of flavonoids, vitamin C, and the antioxidant capacity measured by ABTS are also not affected by oxidation. However, the total content of polyphenols in the treated juice drops by 15 % compared to freshly squeezed juice, nonetheless, the loss is 20 % less than the control untreated. Thus, the material mitigates the loss of total polyphenols and also the antioxidant capacity.Grant RTI2018-100910-B-C44 funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe".Muñoz-Pina, S.; Duch-Calabuig, A.; Ruiz De Assín David, E.; Ros-Lis, JV.; Amorós, P.; Argüelles Foix, AL.; Andrés Grau, AM. (2022). Bioactive compounds and enzymatic browning inhibition in cloudy apple juice by a new magnetic UVM-7-SH mesoporous material. Food Research International. 162(B):1-10. https://doi.org/10.1016/j.foodres.2022.112073110162