59,664 research outputs found

    Desarrollo de papeles biocativos por injerto de moléculas específicas en celulosa

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    Tesis (DCI)--FCEFN-UNC, 2019En la presente tesis se presenta el desarrollo de papeles bioactivos con potencial aplicación en el envasado activo de alimentos. Para tal fin, se propuso el injerto de eugenol, un compuesto de origen natural con propiedades antimicrobiana, antioxidante y repelente de insectos, en celulosa, utilizando ácido policarboxílico como agente ligante. Con el objetivo de evaluar la escalabilidad del proceso propuesto, se estudiaron distintas tecnologías de curado, tales como calentamiento por convección, infrarrojo, microondas y conducción. En todos los casos, se analizaron la influencia de las variables operativas sobre el avance de la reacción y propiedades finales del papel preparado, utilizando un diseño de experimentos Doehlert para elegir las experiencias a realizar, y analizando los resultados mediante metodología de superficie de respuesta y análisis estadístico ANOVA. Se pudo comprobar que la reacción de injerto de eugenol en papel comercial se produjo con éxito en todas las tecnologías estudiadas. Asimismo, se encontraron las condiciones óptimas de reacción para cada una de las tecnologías, para lo cual se buscó un compromiso entre el avance de la reacción y las propiedades finales del material (mecánicas y color). A partir de estas condiciones, se prepararon papeles y se realizó una caracterización más específica para su aplicación como envase de alimentos comparando los papeles modificados con el papel virgen. Se analizaron las propiedades mecánicas por ensayo de tracción, rasgado y punzonado y se midió la absorción de agua y la capacidad de degradación. Por otro lado, las propiedades bioactivas analizadas fueron la actividad antioxidante, antimicrobiana, repelente e insecticida de gorgojos (T. castaneum y R. dominica). Una vez probado que el papel modificado presenta buenas características físicas y bioactivas para su posible aplicación en el envasado de alimentos, se realizaron prototipos de envasado para harina, como alimento representativo de alimentos derivados de cereales, susceptibles al ataque de plagas. En este estudio se analizó la migración de reactivos, propiedades organolépticas y conservación del alimento, arrojando resultados promisorios para la industria de envases de alimentos. Finalmente, se realizó una comparación de las tecnologías de curado ensayadas, analizando diferentes aspectos como avance de reacción, propiedades finales, apariencia, tiempo de reacción, consumo de energía, entre otros, como así también disponibilidad y uso de estas tecnologías a escala industrial, seleccionando la tecnología de conducción como la más adecuada para una propuesta de escalado industrial.Fil: Muratore, Florencia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Muratore, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada; Argentina

    What is the importance of sperm subpopulations?

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    .The study of sperm subpopulations spans three decades. The origin, meaning, and practical significance, however, are less clear. Current technology for assessing sperm morphology (CASA-Morph) and motility (CASA-Mot) has enabled the accurate evaluation of these features, and there are many options for data classification. Subpopulations could occur as a result of the stage of development of each spermatozoon in the subpopulation. Spermatogenesis might contribute to the production of these subpopulations. Insights from evolutionary biology and recent molecular research are indicative of the diversity among male gametes that could occur from unequal sharing of transcripts and other elements through cytoplasmic bridges between spermatids. Sperm cohorts exiting the gonads would contain different RNA and protein contents, affecting the spermatozoon physiology and associations with the surrounding environmental milieu. Subsequently, these differences could affect how spermatozoa interact with the environmental milieu (maturation, mixing with seminal plasma, and interacting with the environmental milieu, or female genital tract and female gamete). The emergence of sperm subpopulations as an outcome of evolution, related to the reproductive strategies of the species, genital tract structures, and copulatory and fertilization processes. This kind of approach in determining the importance of sperm subpopulations in fertilization capacity should have a practical impact for conducting reproductive technologies, inspiring and enabling new ways for the more efficient use of spermatozoa in the medical, animal breeding, and conservation fields. This manuscript is a contribution to the Special Issue in memory of Dr. Duane GarnerS

    Relaciones sociales y creatividad en la empresa: la importancia de la calidad de las interacciones del empleado con su entorno más cercano

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    pp. 1-16La creatividad se está convirtiendo en un fenómeno de especial importancia para las organizaciones. Por ello, existe un interés creciente por comprender cuáles son los factores responsables del rendimiento creativo en los entornos laborales. A pesar de ello, todavía existen lagunas importantes en la literatura sobre la influencia del liderazgo y del comportamiento de los grupos en la creatividad. Con el fin de aportar nueva evidencia empírica al respecto, el objetivo del presente trabajo consiste en analizar cómo influyen las relaciones de intercambio que mantiene el empleado con su superior inmediato y con su grupo de trabajo en la creatividad que pone de manifiesto.S

    Identification of Hindbrain Neural Substrates for Motor Initiation in the hatchling Xenopus laevis Tadpole

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    Animal survival profoundly depends on the ability to detect stimuli in the environment, process them and respond accordingly. In this respect, motor responses to a sensory stimulation evolved into a variety of coordinated movements, which involve the control of brain centres over spinal locomotor circuits. The hatchling Xenopus tadpole, even in its embryonic stage, is able to detect external sensory information and to swim away if the stimulus is considered noxious. To do so, the tadpole relies on well-known ascending sensory pathway, which carries the sensory information to the brain. When the stimulus is strong enough, descending interneurons are activated, leading to the excitation of spinal CPG neurons, which causes the undulatory movement of swimming. However, the activation of descending interneurons that marks the initiation of motor response appears after a long delay from the sensory stimulation. Furthermore, the long-latency response is variable in time, as observed in the slow-summating excitation measured in descending interneurons. These two features, i.e. long-latency and variability, cannot be explained by the firing time and pattern of the ascending sensory pathway of the Xenopus tadpole. Therefore, a novel neuronal population has been proposed to lie in the hindbrain of the tadpole, and being able to 'hold' the sensory information, thus accounting for the long and variable delay of swim initiation. In this work, the role of the hindbrain in the maintenance of the long and variable response to trunk skin stimulation is investigated in the Xenopustadpole at developmental stage 37/38. A multifaceted approach has been used to unravel the neuronal mechanisms underlying the delayed motor response, including behavioural experiments, electrophysiology analysis of fictive swimming, hindbrain extracellular recordings and imaging experiments. Two novel neuronal populations have been identified in the tadpole's hindbrain, which exhibit activation patterns compatible with the role of delaying the excitation of the spinal locomotor circuit. Future work on cellular properties and synaptic connections of these newly discovered populations might shed light on the mechanism of descending control active at embryonic stage. Identifying supraspinal neuronal populations in an embryonic organism could aid in understanding mechanisms of descending motor control in more complex vertebrates

    Interactive Sonic Environments: Sonic artwork via gameplay experience

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    The purpose of this study is to investigate the use of video-game technology in the design and implementation of interactive sonic centric artworks, the purpose of which is to create and contribute to the discourse and understanding of its effectiveness in electro-acoustic composition highlighting the creative process. Key research questions include: How can the language of electro-acoustic music be placed in a new framework derived from videogame aesthetics and technology? What new creative processes need to be considered when using this medium? Moreover, what aspects of 'play' should be considered when designing the systems? The findings of this study assert that composers and sonic art practitioners need little or no coding knowledge to create exciting applications and the myriad of options available to the composer when using video-game technology is limited only by imagination. Through a cyclic process of planning, building, testing and playing these applications the project revealed advantages and unique sonic opportunities in comparison to other sonic art installations. A portfolio of selected original compositions, both fixed and open are presented by the author to complement this study. The commentary serves to place the work in context with other practitioners in the field and to provide compositional approaches that have been taken

    The Idiosyncrasy of Involuntary Musical Imagery Repetition (IMIR) Experiences: The Role of Tempo and Lyrics

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    Involuntary musical imagery repetition (IMIR), colloquially known as “earworms,” is a form of musical imagery that arises involuntarily and repeatedly in the mind. A growing number of studies, based on retrospective reports, suggest that IMIR experiences are associated with certain musical features, such as fast tempo and the presence of lyrics, and with individual differences in music training and engagement. However, research to date has not directly assessed the effect of such musical features on IMIR and findings about individual differences in music training and engagement are mixed. Using a cross-sectional design (Study 1, n = 263), we examined IMIR content in terms of tempo (fast, slow) and presence of lyrics (instrumental, vocal), and IMIR characteristics (frequency, duration of episode and section) in relation to 1) the musical content (tempo and lyrics) individuals most commonly expose themselves to (music-listening habits), and 2) music training and engagement. We also used an experimental design (Study 2, n = 80) to test the effects of tempo (fast or slow) and the presence of lyrics (instrumental or vocal) on IMIR retrieval and duration. Results from Study 1 showed that the content of music that individuals are typically exposed to with regard to tempo and lyrics predicted and resembled their IMIR content, and that music engagement, but not music training, predicted IMIR frequency. Music training was, however, shown to predict the duration of IMIR episodes. In the experiment (Study 2), tempo did not predict IMIR retrieval, but the presence of lyrics influenced IMIR duration. Taken together, our findings suggest that IMIR is an idiosyncratic experience primed by the music-listening habits and music engagement of the individual

    Uso de las histonas circulantes y sus modificaciones post-traduccionales como biomarcadores en sepsis y shock séptico

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    La sepsis es una afección potencialmente mortal causada por una respuesta anormal del huésped a una infección, produciendo respuestas fisiológicas alteradas que dañan los propios tejidos del paciente y pueden provocar disfunción orgánica e incluso la muerte. Asimismo, algunos pacientes sépticos progresan a shock séptico, caracterizado por alteraciones circulatorias, celulares y metabólicas sustanciales que aumentan el riesgo de mortalidad. A pesar de que la sepsis se caracteriza por un mal funcionamiento del sistema inmunológico, lo que a su vez conduce a una respuesta inmune alterada e inmunosupresión, la alta complejidad de la fisiopatología de la sepsis requiere una mayor investigación para comprender las respuestas inmunes que ocurren durante la sepsis. Asimismo, las histonas extracelulares circulantes han ganado relevancia como mediadores citotóxicos en la sepsis, ya que actúan como patrones moleculares asociados a daño, que inducen estrés oxidativo y activan el inflamasoma NLRP3. Estos mecanismos median la activación de la piroptosis, un mecanismo de muerte celular programada que produce inflamación mediante la expresión de IL-18, IL-1β and IL-1α. Sin embargo, a pesar de la evidencia de activación del inflamasoma en las células inmunes durante la sepsis, se desconoce si las histonas extracelulares son capaces de activar los inflamasomas endoteliales y sus consecuencias. En este trabajo destacamos el papel previamente desconocido de las histonas extracelulares, mediando la activación del inflamasoma NLRP3 y la piroptosis en las células endoteliales, contribuyendo a la disfunción endotelial y la desregulación de la respuesta inmune mediada por el endotelio. Asimismo, también demostramos cómo la acetilación de histonas disminuye la activación de la piroptosis. Además, demostramos que la piroptosis se produce en pacientes con shock séptico y los niveles de histonas circulantes se correlacionan con la expresión de citoquinas proinflamatorias y citoquinas piroptóticas, la liberación de factores de adhesión endotelial y la gravedad de la enfermedad. Proponemos la piroptosis mediada por histonas como un nuevo objetivo para desarrollar intervenciones clínicas. De manera similar, hemos analizado las respuestas inmunorelacionadas que ocurren durante las primeras etapas de la sepsis con el objetivo de proporcionar nuevos datos comparando las cantidades de citoquinas, inmunomoduladores y otros mediadores endoteliales en pacientes críticamente enfermos no sépticos, sépticos y de shock séptico. Nuestro enfoque ayudará a caracterizar rápidamente las respuestas inmunes alteradas en pacientes sépticos y de shock séptico ingresados en la Unidad de Cuidados Intensivos. Finalmente analizamos el papel de la metilación del ADN en el control del sistema inmune séptico. Nuestros resultados demostraron el papel central de la metilación del ADN modulando la respuesta molecular en los pacientes de shock séptico y contribuyendo a la inmunosupresión, a través de la alteración de los patrones de metilación de los promotores de IL-10 y TREM-2.Sepsis is a life-threatening condition caused by an abnormal host response to an infection that produce altered physiological responses which damages own tissues of the patient and can result in organ dysfunction and in some cases death. Likewise, a subset of septic patients progresses to septic shock, characterized by substantial circulatory, cellular and metabolic abnormalities, which substantially increase the risk of mortality. Sepsis is characterized by a malfunction of the immune system and it can lead to an altered immune response and immunosuppression. Moreover, the high complexity of the pathophysiology of sepsis requires of further investigation to characterize the immune responses in sepsis and septic shock. Likewise, circulating extracellular histones have gained relevance as cytotoxic mediators in sepsis pathophysiology, since they act as damage-associated molecular patterns, which induce oxidative stress and activate NLRP3 inflammasome. Subsequently, inflammasome mediates pyroptosis activation, a programmed cell death mechanism that produces inflammation through the release of IL-18, IL-1β and IL-1α. However, despite inflammasome activation may occur in immune cells during sepsis, it is unknown if this process also takes place in endothelial cells and particularly whether extracellular histones are capable of activating endothelial inflammasomes and their consequences. In this work we highlight a previously unknown role for extracellular histones, that mediates the activation of NLRP3 inflammasome and pyroptosis in endothelial cells by contributing to endothelial dysfunction and the dysregulation of the immune response mediated by endothelium. Likewise, we demonstrated how histone acetylation decreases pyroptosis activation. Furthermore, we show how pyroptosis occurs in septic shock patients and how circulating histone levels correlate with the expression of pro-inflammatory and pyroptotic cytokines, the release of endothelial adhesion factors and septic shock severity. We propose histone-mediated pyroptosis as a new target to develop clinical interventions. Similarly, we have analyzed the immune-related responses occurring during the early stages of sepsis with the aim of providing new data by comparing the amounts of cytokines, immune modulators and other endothelial mediators in critically-ill non-septic patients, septic and septic shock patients. Our approach will help to rapidly characterize the altered immune responses in septic and septic shock patients admitted in the Intensive Care Unit. Finally, we also analyzed the role of DNA methylation in the control of septic immune system. Our results demonstrated the central role of DNA methylation modulating the molecular response in septic shock patients and contributing to immunosuppression, through the alteration of DNA methylation patterns of IL-10 and TREM2 promoters

    Metodología de intervención para trabajar ODS. Educación a través de las artes

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    La Agenda 2030 presenta 17 Objetivos de Desarrollo Sostenible (ODS), con sus metas e indicadores universales que los países miembros de la ONU emplean para enmarcar sus políticas. Entre las metas del ODS 4 “educación de calidad” encontramos: “asegurar que todos los alumnos adquieran los conocimientos teóricos y prácticos necesarios para promover el desarrollo sostenible, entre otras cosas mediante la educación para el desarrollo sostenible y los estilos de vida sostenibles, los derechos humanos, la igualdad de género, la promoción de una cultura de paz y no violencia, la ciudadanía mundial y la valoración de la diversidad cultural y la contribución de la cultura al desarrollo sostenible”. La educación, se considera el motor de la Agenda 2030 porque, además de representar el centro del ODS 4, desempeña también un papel notable en la implementación de los demás, mejorando su alcance y efectividad. Así pues, entre las disciplinas que sustentan este trabajo se escogió la Educación para el Desarrollo Sostenible y la Ciudadanía Global como marco de acción y punto de partida en la formación de los ciudadanos de un futuro viable, equitativo y habitable. Se continuó investigando las oportunidades del desarrollo de la Competencia Intercultural en las relaciones humanas, aquello que diferencia a unas personas de otras puede aportar al conjunto de la sociedad y cómo la educación permitiría su aprovechamiento. Con todo ello, se planteó el marco didáctico de interacción en el cual se implementó la interculturalidad en el ejercicio educativo. Se estudió así el poder de las artes como medio de motivación e inspiración a la hora de transmitir de la manera más eficaz posible los valores considerados más arriba. El objetivo del presente estudio se centra en demostrar el potencial de las artes para fomentar las competencias comunicativas, sociales, interculturales, emocionales, de ciudadanía y sostenibilidad. Para ello, se ha realizado una investigación aplicada que deriva en una propuesta concreta de intervención con un programa educativo destinado a la enseñanza de lenguas, tanto primera como extranjera, en distintos niveles de la educación formal en Mali y en España, aplicando un método holístico basado en el paradigma interpretativo. A través de la pintura, la literatura y el cine, se plantean una serie de actividades ideadas para crear un entorno educativo integrador, favorecer el empoderamiento del alumnado y promover el pensamiento crítico, la empatía, la resiliencia, la comunicación, la cooperación y la educación intercultural, como competencias esenciales para la consecución de los 17 ODS, la construcción de un mundo transcultural sostenible y el desarrollo de una ciudadanía global preparada para los retos del siglo XXI. En la metodología de este proceso educativo innovador, multidisciplinar, flexible y adaptable, se ha empleado un análisis del proceso de investigación para monitorizarlo adecuadamente (DAFO). Cada una de las propuestas presenta una recogida de datos cualitativos (observación, rúbricas) y cuantitativos (encuestas, entrevistas) y se ofrece un análisis de contraste de los resultados finales. Con todo, se espera facilitar la exigente tarea que supone hacer consciente a la sociedad de base (desde la misma infancia; desde los niveles más bajos de la misma y en todos los niveles de la educación formal) de en qué consisten los ODS y su relevancia para hacer de todas las personas corresponsables directas en su consecución para garantizar un futuro sostenible para toda la ciudadanía global.The 2030 Agenda presents 17 Sustainable Development Goals (SDGs), with their universal targets and indicators that UN member countries use to frame their policies. Among the targets of SDG 4 “quality education,” we find the one that seeks: “to ensure that all students acquire the theoretical and practical knowledge necessary to promote sustainable development, among other things through education for sustainable development and sustainable lifestyles, human rights, gender equality, the promotion of a culture of peace and non-violence, world citizenship and the appreciation of cultural diversity and the contribution of culture to sustainable development”. Education is considered the engine of the 2030 Agenda because, in addition to representing the centre of SDG 4, it also plays a notable role in the implementation of the others, improving their scope and effectiveness. Among the disciplines that support this research, Education for Sustainable Development and Global Citizenship sets the framework for action and represents a starting point in the formation of citizens for a viable, equitable and habitable future. Global citizenship implies human relations and those and intrinsically shaped by culture. Intercultural Education and, more specifically, the development of Intercultural Competence needed to be considered. What differentiates some people from others can contribute to society as a whole and education is the means to explore and understand. For the design of a didactic framework of interaction, the power of the arts was studied as a means of motivation and inspiration when transmitting the values considered above in the most effective way possible. The objective of this study focuses on proving the potential of the arts to promote communicative, social, intercultural, emotional, citizenship and sustainability skills. For this, the theoretical research derived in a concrete intervention proposal with an educational program in language teaching, both first and foreign languages, at different levels of formal education in Mali and Spain, applying a holistic method based on the interpretive paradigm. Through painting, literature and cinema, a series of activities were designed to create an inclusive educational environment, favour the empowerment of students and promote critical thinking, empathy, resilience, communication, cooperation and intercultural education, as essential skills for the achievement of the 17 SDGs, the construction of a sustainable transcultural world and the development of global citizenship prepared for the challenges of the 21st century. In the methodology of this innovative, multidisciplinary, flexible and adaptable educational process, an analysis of the research process has been used to adequately monitor it (SWOT). Each of the proposals presents a collection of qualitative data (observation, rubrics) and quantitative data (surveys, interviews) and contrast analysis of the final results is offered. All in all, it is expected to facilitate the demanding task of making basic society aware (from childhood itself, from its lowest levels and at all levels of formal education) of what the SDGs consist of and their relevance to make all people directly co-responsible in its achievement to guarantee a sustainable future for all global citizens

    Rainfall Prediction: A Comparative Analysis of Modern Machine Learning Algorithms for Time-Series Forecasting

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    Rainfall forecasting has gained utmost research relevance in recent times due to its complexities and persistent applications such as flood forecasting and monitoring of pollutant concentration levels, among others. Existing models use complex statistical models that are often too costly, both computationally and budgetary, or are not applied to downstream applications. Therefore, approaches that use Machine Learning algorithms in conjunction with time-series data are being explored as an alternative to overcome these drawbacks. To this end, this study presents a comparative analysis using simplified rainfall estimation models based on conventional Machine Learning algorithms and Deep Learning architectures that are efficient for these downstream applications. Models based on LSTM, Stacked-LSTM, Bidirectional-LSTM Networks, XGBoost, and an ensemble of Gradient Boosting Regressor, Linear Support Vector Regression, and an Extra-trees Regressor were compared in the task of forecasting hourly rainfall volumes using time-series data. Climate data from 2000 to 2020 from five major cities in the United Kingdom were used. The evaluation metrics of Loss, Root Mean Squared Error, Mean Absolute Error, and Root Mean Squared Logarithmic Error were used to evaluate the models' performance. Results show that a Bidirectional-LSTM Network can be used as a rainfall forecast model with comparable performance to Stacked-LSTM Networks. Among all the models tested, the Stacked-LSTM Network with two hidden layers and the Bidirectional-LSTM Network performed best. This suggests that models based on LSTM-Networks with fewer hidden layers perform better for this approach; denoting its ability to be applied as an approach for budget-wise rainfall forecast applications

    The applied psychology of addictive orientations : studies in a 12-step treatment context.

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    The clinical data for the studies was collected at The PROMIS Recovery Centre, a Minnesota Model treatmentc entre for addictions,w hich encouragesth e membership and use of the 12 step Anonymous Fellowships, and is abstinence based. The area of addiction is contextualised in a review chapter which focuses on research relating to the phenomenon of cross addiction. A study examining the concept of "addictive orientations" in male and female addicts is described, which develops a study conductedb y StephensonM, aggi, Lefever, & Morojele (1995). This presents study found a four factor solution which appeared to be subdivisions of the previously found Hedonism and Nurturance factors. Self orientated nurturance (both food dimensions, shopping and caffeine), Other orientated nurturance (both compulsive helping dimensions and work), Sensation seeking hedonism (Drugs, prescription drugs, nicotine and marginally alcohol), and Power related hedonism (Both relationship dimensions, sex and gambling. This concept of "addictive orientations" is further explored in a non-clinical population, where again a four factor solution was found, very similar to that in the clinical population. This was thought to indicate that in terms of addictive orientation a pattern already exists in this non-clinical population and that consideration should be given to why this is the case. These orientations are examined in terms of gender differences. It is suggested that the differences between genders reflect power-related role relationships between the sexes. In order to further elaborate the significance and meaning behind these orientations, the next two chapters look at the contribution of personality variables and how addictive orientations relate to psychiatric symptomatology. Personality variables were differentially, and to a considerable extent predictably involved with the four factors for both males and females.Conscientiousness as positively associated with "Other orientated Nurturance" and negatively associated with "Sensation seeking hedonism" (particularly for men). Neuroticism had a particularly strong association with the "Self orientated Nurturance" factor in the female population. More than twice the symptomatology variance was explained by the factor scores for females than it was for males. The most important factorial predictors for psychiatric symptomatology were the "Power related hedonism" factor for males, and "Self oriented nurturance" for females. The results are discussed from theoretical and treatment perspectives
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