Effect of Chitin Whiskers on the Molecular Dynamics of Carrageenan-Based Nanocomposites

[EN] Films of carrageenan (KC) and glycerol (g) with different contents of chitin nanowhiskers (CHW) were prepared by a solution casting process. The molecular dynamics of pure carrageenan (KC), carrageenan/glycerol (KCg) and KCg with different quantities of CHWs as a filler was studied using dielectric relaxation spectroscopy. The analysis of the CHW effect on the molecular mobility at the glass transition, T-g, indicates that non-attractive intermolecular interactions between KCg and CHW occur. The fragility index increased upon CHW incorporation, due to a reduction in the polymer chains mobility produced by the CHW confinement of the KCg network. The apparent activation energy associated with the relaxation dynamics of the chains at T-g slightly increased with the CHW content. The filler nature effect, CHW or montmorillonite (MMT), on the dynamic mobility of the composites was analyzed by comparing the dynamic behavior of both carrageenan-based composites (KCg/xCHW, KCg/xMMT).This research was funded by the DGCYT grant number [MAT2015-63955-R] and the Vice-Rectorate for Research of the Pontificia Universidad Catolica del Peru and the the Peruvian Science and Technology Program (INNOVATE-PERU) And The APC was funded by MDPI.Carsí Rosique, M.; Sanchis Sánchez, MJ.; Gómez, CM.; Rodriguez, S.; García-Torres, F. (2019). Effect of Chitin Whiskers on the Molecular Dynamics of Carrageenan-Based Nanocomposites. Polymers. 11(6):1-16. https://doi.org/10.3390/polym11061083116116Zheng, Y., Monty, J., & Linhardt, R. J. (2015). Polysaccharide-based nanocomposites and their applications. Carbohydrate Research, 405, 23-32. doi:10.1016/j.carres.2014.07.016Jamróz, E., Kulawik, P., & Kopel, P. (2019). 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Transformación del modelo de clases uml a oracle9i® bajo la directiva mda: un caso de estudio

La Arquitectura Orientada a Modelos (MDA) es la propuesta de refinamiento de la OMG orientada a la generación automática de código a partir de los Modelos UML de Sistemas Independientes de la Plataforma de Implementación. En este trabajo se presenta una metodología para transformar el Modelo de Clases UML a un Modelo UML Dependiente de la Plataforma Oracle9i®, siguiendo los lineamientos básicos presentados por esta arquitectura y utilizando a UML como lenguaje de modelado a través de todos los pasos de dicha transformación. Inicialmente las reglas de transformación del Modelo de Clases de UML al Modelo Objeto-Relacional soportado por Oracle9i® son recopiladas en Español y adaptadas a nivel de metamodelo, para lo cual fue necesario elaborar un metamodelo simplificado de la plataforma Oracle9i®. Este conjunto de reglas se hace automatizable al expresarlas en un formalismo lógico, que sea fácilmente ejecutable por una herramienta CASE que soporte un lenguaje formal. Finalmente, se aplican las reglas de refinamiento formalizadas al Modelo de Clases de un Caso Práctico de estudio obteniendo como resultado, un Modelo UML instancia del Metamodelo de la Plataforma Oracle9i®. Los aspectos del Modelo de Clases en los que se hace énfasis en la transformación son las invariantes y reglas de derivación de atributos definidas en el lenguaje formal OCL, así como las relaciones de asociación, composición y generalización entre Clases

Effects of Gamma Irradiation on the Kinetics of the Adsorption and Desorption of Hydrogen in Carbon Microfibres

In this study, three types of carbon fibres were used, they were ex-polyacrylonitrile carbon fibres with high bulk modulus, ex-polyacrylonitrile fibres with high strength, and vapour grown carbon fibres. All the samples were subjected to a hydrogen adsorption process at room temperature in an over-pressured atmosphere of 25 bars. The adsorption process was monitored through electrical resistivity measurements. As conditioning of the fibres, a chemical activation by acid etching followed by ¿-ray irradiation with 60Co radioisotopes was performed. The surface energy was deter-mined by means of the sessile drop test. Both conditioning treatments are supplementary; the chemical activation works on the outer surface and the ¿-irradiation works in the bulk material as well. Apparently, the most significant parameter for hydrogen storage is the crystallite size. From this point of view, the mostPeer Reviewe

Emergence of assortative mixing between clusters of cultured neurons

The analysis of the activity of neuronal cultures is considered to be a good proxy of the functional connectivity of in vivo neuronal tissues. Thus, the functional complex network inferred from activity patterns is a promising way to unravel the interplay between structure and functionality of neuronal systems. Here, we monitor the spontaneous self-sustained dynamics in neuronal cultures formed by interconnected aggregates of neurons (clusters). Dynamics is characterized by the fast activation of groups of clusters in sequences termed bursts. The analysis of the time delays between clusters' activations within the bursts allows the reconstruction of the directed functional connectivity of the network. We propose a method to statistically infer this connectivity and analyze the resulting properties of the associated complex networks. Surprisingly enough, in contrast to what has been reported for many biological networks, the clustered neuronal cultures present assortative mixing connectivity values, meaning that there is a preference for clusters to link to other clusters that share similar functional connectivity, as well as a rich-club core, which shapes a"connectivity backbone" in the network. These results point out that the grouping of neurons and the assortative connectivity between clusters are intrinsic survival mechanisms of the culture

Occurrence of antibiotics and bacterial resistance in wastewater and sea water from the Antarctic

The potential presence of introduced antibiotics in the aquatic environment is a hot topic of concern, particularly in the Antarctic, a highly vulnerable area protected under the Madrid protocol. The increasing presence of human population, especially during summer, might led to the appearance of pharmaceuticals in wastewater. The previous discovery of Escherichia coli strains resistant to antibiotics in sea water and wastewater collected in King George Island motivated our investigation on antibiotics occurrence in these samples. The application of a multi-residue LCMS/MS method for 20 antibiotics, revealed the presence of 8 compounds in treated wastewater, mainly the quinolones ciprofloxacin and norfloxacin (92% and 54% of the samples analyzed, average concentrations 0.89 μg/L and 0.75 μg/L, respectively) and the macrolides azithromycin and clarithromycin (15% positive samples, and average concentrations near 0.4 μg/L), and erythromycin (38% positive samples, average concentration 0.003 μg/L). Metronidazole and clindamycin were found in one sample, at 0.17 and 0.1 μg/L, respectively; and trimethoprim in two samples, at 0.001 μg/L. Analysis of sea water collected near the outfall of the wastewater discharges also showed the sporadic presence of 3 antibiotics (ciprofloxacin, clindamycin, trimethoprim) at low ng/L level, illustrating the impact of pharmaceuticals consumption and the poor removal of these compounds in conventional WWTPs. The most widespread antibiotic in sea water was ciprofloxacin, which was found in 15 out of 34 sea water samples analyzed, at concentrations ranging from 4 to 218 ng/L. Bacteria resistance was observed for some antibiotics identified in the samples (e.g. trimetropim and nalidixic acid –a first generation quinolone). However, resistance to some groups of antibiotics could not be correlated to their presence in the water samples due to analytical limitations (penicillins, tetraciclines). On the contrary, for some groups of antibiotics detected in samples (macrolides), the antibacterial activity against E. Coli was not investigated because these antibiotics do not include this bacterial species in their spectrum of activity. Our preliminary data demonstrate that antibiotics occurrence in the Antarctic aquatic environment is an issue that needs to be properly addressed. Periodical monitoring of water samples and the implementation of additional treatments in the WWTPs are recommended as a first step to prevent potential problems related to the presence of antibiotics and other emerging contaminants in the near future in Antarctica

Education and innovation - vet students into technology companies

VET education is an effective and accessible way for students, to improve their employability and inclusion possibilities. It allows them to train technically in a short time to do a job and try to access the labor market. However, not even obtaining a qualification aimed at vocational training ensures access to the labor market or real possibilities of emancipation. The success of VET graduates in their first work experience joining technology companies requires the development of many skills that are common to all professional careers, but also specific skills that derive from the innovative nature of the work method and objectives of these companies. For this reason, within the framework of the Erasmus + Program, the project VET STUDENTS İNTO TECHNOLOGY COMPANİES: A VET students mobility network in the technological sector through a virtual environment with specific materials for critical thinking is being developed with the aim of promoting employability and inclusion of VET students at risk of exclusion. The project focuses on the creation of virtual tools, collaborative work methodologies and virtual training materials that allow these young people to improve their critical thinking capacity and their technological and digital skills. The project's methodology is based on the combination of the creation of training materials and a network of mobility in high-tech centres, where students will carry out a first work experience. Regarding training materials, one of the main results of this project is PERSONALIZED DIGITAL COURSE FOR LABOR TRAINING IN A TECHNOLOGICAL CENTER. This course generates personalized learning based on the student's previous knowledge and the characteristics of the technological company in which they will carry out their internship. The course follows an innovative methodology based on microlearning, a learning characterized by the resolution of relatively small exercises (pills) that are focused on the development of technical and work skills and the reinforcement of critical thinking as a fundamental mechanism. The objective of this course is not so much to provide new knowledge as to develop skills that allow the students to face problems or tasks unknown to them until then: self-training skills, assess their own way of reasoning, set objectives, raise relevant questions, state hypothesis, search for information, intellectual integrity, oral and written communication, work in multidisciplinary teams. Along with this course, within the framework of this project, the result ON YOUR SIDE is being developed, a digital educational software available for mobile devices, which will accompany the student throughout the mobility process, providing useful information such as specific training resources focused on the company where they will carry out their mobility, linguistic resources, collaborative work tools, as well as social integration resources in the destination country, among others. From this App, students will be able to access the aforementioned course. In this paper we present how, through microlearning methodology and critical thinking, students can solve the content pills through their autonomy and self-discovery.This work has been funded by the Erasmus + program within the 2019-1-ES01-KA202-064569 project, Spanish Service for the Internationalization of Education (SEPIE

Comparación de métodos para la recuperación y determinación de la prevalencia de Streptococcus agalactiae en mujeres gestantes de Medellín

ResumenStreptococcus agalactiae es un coco Gram positivo que se encuentra frecuentemente asociado a infecciones en neonatos, mujeres embarazadas y adultos inmunocomprometidos.ObjetivoComparar la sensibilidad de los métodos para la recuperación y la determinación de la prevalencia de S. agalactiae en un grupo de mujeres gestantes de Medellín.Materiales y métodosSe llevó a cabo un estudio descriptivo de corte. La población estudiada fueron 362 mujeres gestantes que consultaron en el periodo comprendido entre febrero y octubre de 2008, a las que se les tomaron muestras con hisopo del introito vaginal y de la región anal. Las muestras secultivaron simultáneamente en agar Nueva Granada y caldo Todd Hewitt con suplemento de antibióticos, a partir del cual se hizo un subcultivo en agar sangre de carnero al 5%.ResultadosAl comparar el método de recuperación en agar Nueva Granada con el método de referencia en caldo Todd Hewitt, la sensibilidad del primero fue de 44% y el valor diagnóstico positivo de 58%; presentó una alta especificidad (98%) y un valor diagnóstico negativo de 99%. Se identificó S. agalactiae en 21 (5,8%) gestantes.ConclusiónEl cultivo en caldo Todd Hewitt es un método sensible para la recuperación de S. agalactiae. Por consiguiente, se recomienda continuar con esta metodología para la tamización de mujeres gestantes en nuestro medio. La prevalencia de 5,8% encontrada en este estudio concuerda con los reportes de la literatura mundial y, teniendo en cuenta que la tasa de transmisión vertical es, aproximadamente, de 50% (1), se demuestra la necesidad de implementar medidas de vigilancia epidemiológica en nuestro medio.Streptococcus agalactiae, is a Gram positive coccus that is frequently associated to infections in neonates, pregnant women, and immunocompromised adults.ObjectiveCompare method sensitivity for recovery from S. agalactiae and to determine its prevalence in a group of pregnant women of the city of Medellín.Materials and methodsCross-sectional descriptive study. The population was pregnant women of Medellín who consulted from February to October, 2008; 362 pregnant women were included; the samples were taken from vagina introitus and anal area. The samples were simultaneously cultured in New Granada Agar and Todd Hewitt Broth supplemented with antibiotics, which was the base for the performance of a subculture in Ram Blood Agar at 5%.ResultsWhen comparing the New Granada Agar method of recovery with the Todd Hewitt Broth gold test, the sensitivity of the first was 44% and the positive predictive value was 58%; it presented 98% specificity and a negative predictive value of 99%. S. agalactiae was found in 21 (5.8%) pregnant women.ConclusionsTodd Hewitt Broth is a sensitive method for the recovery from S. agalactiae; therefore, continuing with this methodology for the screening of pregnant women in our environment is recommended. The 5,8% prevalence found in this study is consistent with the reports in world-wide literature. Considering that the rate of vertical transmission is approximately 50%, the need to implement epidemiological surveillance measures in our environment is evident

VET students into technology companies: a microlearning digital course to train critical thinking skills

This microlearning course is designed to support VET graduates or students, especially those with fewer opportunities, who join a technology company at the beginning of their professional career. It has been developed within the framework of the Erasmus + project “VET STUDENTS İNTO TECHNOLOGY COMPANİES: A VET students mobility network in the technological sector through a virtual environment with specific materials for critical thinking”. This is an intiative co-financed by the Erasmus + Programme, with a personalized digital course format, to take into account both the previous training of the VET student or graduate and the type of company they will join. The course has in its sights to develop in the VET student the specific competences required by the technology company to address the problems typical of fields of leading technology innovation, as well as fitting in multidisciplinary teams. To do this, this course generates an innovative methodology in which the education itinerary is built based on previous knowledge of the student and the needs and work field of the technology company. Besides its contents strengthen critical thinking as an essential mechanism for work in both dynamic and technology sectors. For that purpose, the student is asked a series of questions in the form of problems that, in addition to being related to the study plans of VET studies, require for their solution the search for information, its analysis and many times the making of a decision or adopting a personal position on it. We aim with our training projects, within the Erasmus + program, to convince students that they are capable of going further and further in the development of their professional skills being the technology sector an acceptable option for them, making their work increasingly valuable for their inclusion, for their own personal development, for that of the company in which they work and for society. But for this certain skills are required, and one of the most important is learning to learn autonomously and to accurately analyse the information received and the decisions that are made from it. It is generally true that the problems that one encounters in professional practice are not going to be the ones that you were taught in your VET studies. Vocational training has to head for equipping students with the necessary tools to face the new problems that they will face in their job and to grow professionally every day. We intend to show how valuable critical thinking skills are in analysing our way of thinking and making decisions. In this paper we present examples of the exercises included in the course, how their approach and the processes that have led to a solution relate with the standards of critical thinking and the different levels of help that are offered to the student for their solution. The course is accessible from a digital educational software “ON YOUR SIDE: VIRTUAL ASSISTANT FOR EUROPEAN MOBILITIES IN TECHNOLOGICAL CENTERS” developed in the framework of this Erasmus+ project in order to develop cooperative work between students with fewer opportunities doing their internships in technology companies and their inclusion in new job posts. We will also present this software in a very summarized way in this article.This work has been funded by the Erasmus + program within the 2019-1-ES01-KA202-064569 project, Spanish Service for the Internationalization of Education (SEPIE

León (Spain) Health professionals’ knowledge and clinical practice towards the relationship between cardiovascular diseases and periodontal disease

Cardiovascular pathologies have a high prevalence in the geriatric population, with acute myocardial infarction being one of the main causes of death in Spain. These pathologies have a systemic inflammatory component that is of vital importance. We also know in dentistry that the main gingival pathogens are capable of generating a systemic inflammatory response, being indirectly involved in the development of the atherosclerotic lesion, assuming, therefore, that periodontal disease is a cardiovascular risk factor. The objective of this study is to determine the knowledge of health professionals who treat cardiovascular diseases about periodontal disease and its relationship with heart disease.A health survey was carried out on 100 Cardiologists, Internists and General Practitioners in the province of León. Points of interest in this survey: the professional’s own oral health, knowledge of the relationship between periodontal and heart disease and, lastly, the training received in medicine on oral health.60% of professionals reviewed their oral health annually and 20% randomly. 48% of health professionals were unaware of periodontal diseases, 77% claimed to have not received university training in this regard, only 13% of those surveyed acknowledged having received more than 10 hours of training on oral health in their experience and finally, 90% thought that training in both Medicine and Dentistry should be collaborative.The degree of knowledge of health professionals regarding oral health is poor (77%), therefore the number of collaborative consultations with dental professionals is low (<63%). Training projects targeting a correct preventive medicine are shown to be necessary

Dinámica poblacional de la oruga del cascabullo Helicoverpa gelotopoeon Dyar (Lepidoptera: Noctuidae) en el cultivo de garbanzo

El garbanzo (Cicer arietinum L.) es una fabácea de ciclo anual que fue introducida en la Argentina durante la etapa colonial, en el actual departamento cordobés de Cruz del Eje, y desde allí se expandió hacia el norte (Marginet Campos, 2001). Se la cultiva en invierno, principalmente en la región semiárida que comprende las provincias de Salta, Córdoba, Tucumán, Jujuy, Catamarca y San Luis (Carreras, 1999; García Medina et al., 2007).Fil: Scalora, Franco S.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Casmuz, Augusto S.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Cazado, Lucas Emiliano. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aralde, Marcos. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Aybar Guchea, Matias. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Fadda, Lucas. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Gómez, Mario. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Gómez, Horacio. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Tolosa, Gerardo. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Vera, Alejandro. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Gastaminza, Gerardo. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Willink, Eduardo. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; ArgentinaFil: Espeche, Clara M.. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentin