21,944 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

    Gamification in E-Learning: game factors to strengthen specific English pronunciation features in undergraduate students at UPTC Sogamoso

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    Appendix A Characterization survey (104), Appendix B. EFL Students’ questionnaire (109), Appendix C. Characterization survey: data treatment question (113), Appendix D. Informed consent letter, English version (114), Appendix E. Carta de consentimiento informado, versión en español (117), Appendix F. Time Schedule (120), Appendix G. Sample Challenges at Moodle (126), Appendix H. Participants’ questionnaire results (128).La gamificación es un término que suele denotar el uso de componentes del juego en situaciones no relacionadas con el juego en sí para crear experiencias de aprendizaje agradables, divertidas y motivadoras para los estudiantes (Werbach y Hunter, 2012). Por lo tanto, el análisis de los factores básicos de los juegos se convierte en algo esencial a la hora de definir y utilizar la gamificación como estrategia de mediación del inglés como lengua extranjera para fortalecer rasgos específicos de pronunciación en los estudiantes de pregrado de la UPTC Sogamoso. El procedimiento de estudio se basa en la investigación acción mediante la implementación de la estrategia de gamificación para la mediación en la pronunciación del inglés, orientada a treinta estudiantes de diferentes programas de ingeniería, administración y tecnología con niveles heterogéneos de dominio del inglés. Las actividades se centran principalmente en la producción de sonidos, el ritmo, el acento y la entonación, los rasgos de pronunciación segmental y suprasegmental. Los resultados arrojaron una evidente mejora en las características segméntales y suprasegmentales de la percepción en la pronunciación de los participantes así como la contribución del objetivo de los juegos a la instrucción fonética y fonológica, la sensación en el juego a la motivación para mejorar la pronunciación, el reto establecido en los juegos a la actitud positiva de los participantes, y la sociabilidad a la exposición practica de la pronunciación inglesa.Gamification is a relatively new term that often denotes the use of game components in situations unrelated to the game itself to create enjoyable, fun, and motivating learning experiences for students (Werbach and Hunter, 2012). Therefore, analyzing the games' basic factors becomes essential when defining and using gamification as a strategy for English as Foreign Language mediation to strengthen specific pronunciation features in UPTC Sogamoso undergraduate students. The study procedure is based on action research by implementing the gamification strategy for mediation in English pronunciation, oriented to thirty students from different engineering, management, and technology programs at heterogeneous levels of English proficiency. The activities mainly focus on sound production, rhythm, stress, and intonation, segmental and suprasegmental pronunciation features. The results showed an evident improvement in the segmental and suprasegmental features of the participants' pronunciation perception as well as the contribution of game goals to phonetics and phonological instruction, the game sensation to the motivation for pronunciation improvement, the game challenge to the participants' positive attitude, and the sociality to the English pronunciation exposure practice

    Building body identities - exploring the world of female bodybuilders

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    This thesis explores how female bodybuilders seek to develop and maintain a viable sense of self despite being stigmatized by the gendered foundations of what Erving Goffman (1983) refers to as the 'interaction order'; the unavoidable presentational context in which identities are forged during the course of social life. Placed in the context of an overview of the historical treatment of women's bodies, and a concern with the development of bodybuilding as a specific form of body modification, the research draws upon a unique two year ethnographic study based in the South of England, complemented by interviews with twenty-six female bodybuilders, all of whom live in the U.K. By mapping these extraordinary women's lives, the research illuminates the pivotal spaces and essential lived experiences that make up the female bodybuilder. Whilst the women appear to be embarking on an 'empowering' radical body project for themselves, the consequences of their activity remains culturally ambivalent. This research exposes the 'Janus-faced' nature of female bodybuilding, exploring the ways in which the women negotiate, accommodate and resist pressures to engage in more orthodox and feminine activities and appearances

    Examination of a Brief, Self-Paced Online Self-Compassion Intervention Targeting Intuitive Eating and Body Image Outcomes among Men and Women

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    Ideals for appearance and body image are pervasive in Western culture in which men and women are portrayed with unrealistic and often unattainable standards (Ferguson, 2013; Martin, 2010). Exposure and reinforcement have created a culture of social acceptance and internalization of these ideals, contributing to pervasive body image disturbance (i.e., body dissatisfaction; Fallon et al., 2014; Stice, 2001; Thompson & Stice, 2001; Thompson et al., 1999). Research has suggested that body dissatisfaction is expressed differently across sexes (Grossbard et al., 2008), with attention to thin ideals among women and muscular ideals among men. Body dissatisfaction has been linked to numerous poor outcomes, including dieting, unhealthy weight control behaviors, disordered eating, and increased psychopathology. Although dieting is one of the primary mechanisms employed to reduce body dissatisfaction (Thompson & Stice, 2001), research has shown that such efforts are contraindicated as dieting predicts weight gain over time (Pietiläinen et al., 2012) as well as preoccupation with food, disordered eating, eating disorders, emotional distress, and higher body dissatisfaction (Grabe et al., 2007; Johnson & Wardle, 2005; Neumark- Sztianer et al., 2006; Paxton et al., 2006; Tiggemann, 2005). Restrictive dietary behaviors suppress physiological cues to eat (e.g., hunger) that presents a vulnerability to eating in response to alternative cues, both internal (e.g., emotions) and external (e.g., availability of food). Intuitive eating is a non-restrictive approach to eating that encourages adherence to internal physiological cues to indicate when, what, and how much to eat (Tylka, 2006) and has demonstrated an inverse relationship with disordered eating, restrained eating, food preoccupation, dieting, body dissatisfaction, and negative affect (Bruce & Ricciardelli, 2016). Self-compassion, relating to oneself in a caring and supportive manner (Neff, 2003a), has been proposed as a pathway to increase intuitive eating and reduce body dissatisfaction (Neff & Knox, 2017; Schoenefeld & Webb, 2013; Webb & Hardin, 2016). Research has highlighted the efficacy of self-compassion interventions in addressing weight-related concerns (Rahimi-Ardabili et al., 2018) as well as brief experiential exercises for reducing body dissatisfaction (Moffitt et al., 2018). Additionally, there is a growing body of evidence supporting the efficacy of internet-based self-compassion interventions (Mak et al., 2018; Kelman et al., 2018; Nadeau et al., 2020). The purpose of the current study was to examine the effectiveness of a brief, self-paced online self-compassion intervention targeting body image and adaptive eating behaviors and potential mechanisms of change (e.g., self-compassion and psychological flexibility) among undergraduate men and women. This study also examined outcomes among men and women in the area of self-compassion, body dissatisfaction, and intuitive eating as research has highlighted the need to determine who benefits more from self-compassion interventions (Rahimi-Ardabili et al., 2018). The study compared a one-hour, self-guided online self-compassion intervention to an active control condition. The intervention was comprised of psychoeducation, experiential exercises, and mindfulness practice designed to increase self-compassion surrounding body image and eating behaviors. In contrast, the active control condition consisted of self-care recommendations and self-assessments for nutrition, exercise, and sleep. The study was administered over three parts (e.g., baseline, intervention, and follow-up) in which variables of interest were assessed at each time point. Outcome variables included self-compassion, intuitive eating, disordered eating, body appreciation, muscle dysmorphia, internalized weight bias, fear of self-compassion, and psychological inflexibility. Participants were randomized on a 2:1 intervention to control ratio at the second time point in order to make comparisons between groups while simultaneously having sufficient power for examining mediation and moderation within the treatment condition. Overall, 1023 individuals (64% women, Mage = 18.9, 67.4% white) signed informed consent and participated in at least one part of the study whereas 101 participants (71% women, Mage = 19.3, 71% white) completed all three study portions. As predicted, self-compassion was correlated with all variables of interest, and all study variables were correlated with each other (p < .01). In contrast to hypothesized outcomes, the self-compassion condition failed to demonstrate improvements across time or between conditions on all study outcomes. These results persisted when participants were screened for levels of intuitive eating as well. Contrary to prediction, internalized weight bias, muscle dysmorphia, and fear of self-compassion demonstrated increased levels within the intervention condition and decreases in the control condition. There were significant gender differences on multiple outcome variables, with men demonstrating higher levels of self-compassion and body appreciation whereas women endorsed higher levels of disordered eating, internalized weight bias, muscle dysmorphia, and psychological inflexibility. Additionally, there were significant gender interactions for internalized weight bias, body appreciation, and muscle dysmorphia. The interactions existed such that men demonstrated increased internalized weight bias and muscle dysmorphia across time whereas women displayed decreased weight bias and muscle dysmorphia. The opposite pattern was found within body appreciation; women demonstrated increased body appreciation across time while men reported decreased levels of body appreciation. Despite this study’s intent to examine underlying mechanisms of change, the condition in which participants were randomly selected did not have any relationship, positive or negative, with the outcome variables of interest. As such, mediation within the current study was not conducted as it would violate statistical assumptions required to examine this hypothesis. Finally, upon examining the moderating relationship of fear of self-compassion between self-compassion and outcome variables, there were main effects for self-compassion on intuitive eating, emotional eating, internalized weight bias, body appreciation, and psychological inflexibility as well as main effects of fear of self-compassion on psychological inflexibility. There were significant interactions for intuitive eating and emotional eating, such that as fear of self-compassion increased, the effect of self-compassion on intuitive eating decreased, and the effect of self-compassion on reducing emotional eating behaviors decreased. Overall, the brief, self-paced online intervention delivered in the current study did not prove to be an effective means for improving self-compassion, intuitive eating, body appreciation, disordered eating, muscle dysmorphia, and psychological inflexibility. Nevertheless, the relationships between self-compassion and outcome variables of interest throughout the study mirror that of the existing literature. Findings from this study, in general, were also consistent with differences between men and women despite a gap in the research for intervention outcomes. Although fear of self-compassion demonstrated a moderating effect on the relationship between self-compassion and intuitive eating as well as emotional eating, this does not account for the lack of significant findings. The context surrounding this study, such as the COVID-19 pandemic, provided a considerable challenge to examining the efficacy of the current intervention. However, the findings of this study suggest future research will likely need to identify ways to enhance the delivery of experiential exercises that encourage engagement, provide a safe and warm environment for participants, and create flexibility and willingness surrounding painful and difficult experiences in order to undermine internalized and socially accepted beliefs about body image and eating behaviors

    Machine learning based adaptive soft sensor for flash point inference in a refinery realtime process

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    In industrial control processes, certain characteristics are sometimes difficult to measure by a physical sensor due to technical and/or economic limitations. This fact is especially true in the petrochemical industry. Some of those quantities are especially crucial for operators and process safety. This is the case for the automotive diesel Flash Point Temperature (FT). Traditional methods for FT estimation are based on the study of the empirical inference between flammability properties and the denoted target magnitude. The necessary measures are taken indirectly by samples from the process and analyzing them in the laboratory, this process implies time (can take hours from collection to flash temperature measurement) and thus make it very difficult for real-time monitorization, which in fact results in security and economical losses. This study defines a procedure based on Machine Learning modules that demonstrate the power of real-time monitorization over real data from an important international refinery. As input, easily measured values provided in real-time, such as temperature, pressure, and hydraulic flow are used and a benchmark of different regressive algorithms for FT estimation is presented. The study highlights the importance of sequencing preprocessing techniques for the correct inference of values. The implementation of adaptive learning strategies achieves considerable economic benefits in the productization of this soft sensor. The validity of the method is tested in the reality of a refinery. In addition, real-world industrial data sets tend to be unstable and volatile, and the data is often affected by noise, outliers, irrelevant or unnecessary features, and missing data. This contribution demonstrates with the inclusion of a new concept, called an adaptive soft sensor, the importance of the dynamic adaptation of the conformed schemes based on Machine Learning through their combination with feature selection, dimensional reduction, and signal processing techniques. The economic benefits of applying this soft sensor in the refinery's production plant and presented as potential semi-annual savings.This work has received funding support from the SPRI-Basque Gov- ernment through the ELKARTEK program (OILTWIN project, ref. KK- 2020/00052)

    Coverage measurements of NB-IoT technology

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    Abstract. The narrowband internet of things (NB-IoT) is a cellular radio access technology that provides seamless connectivity to wireless IoT devices with low latency, low power consumption, and long-range coverage. For long-range coverage, NB-IoT offers a coverage enhancement (CE) mechanism that is achieved by repeating the transmission of signals. Good network coverage is essential to reduce the battery usage and power consumption of IoT devices, while poor network coverage increases the number of repetitions in transmission, which causes high power consumption of IoT devices. The primary objective of this work is to determine the network coverage of NB-IoT technology under the University of Oulu’s 5G test network (5GTN) base station. In this thesis work, measurement results on key performance indicators such as reference signal received power (RSRP), reference signal received quality (RSRQ), received signal strength indicator (RSSI), and signal to noise plus interference (SINR) have been reported. The goal of the measurement is to find out the NB-IoT signal strength at different locations, which are served by the 5GTN cells configured with different parameters, e.g., Tx power levels, antenna tilt angles. The signal strength of NB-IoT technology has been measured at different places under the 5GTN base station in Oulu, Finland. Drive tests have been conducted to measure the signal strength of NB-IoT technology by using the Quectel BG96 module, Qualcomm kDC-5737 dongle and Keysight Nemo Outdoor software. The results have shown the values of RSRP, RSRQ, RSSI, and SINR at different locations within several kilometres of the 5GTN base stations. These values indicate the performance of the network and are used to assess the performance of network services to the end-users. In this work, the overall performance of the network has been checked to verify if network performance meets good signal levels and good network coverage. Relevant details of the NB-IoT technology, the theory behind the signal coverage and comparisons with the measurement results have also been discussed to check the relevance of the measurement results

    Self-help/mutual aid groups in mental health : ideology, helping mechanisms and empowerment

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    In the last quarter of the twentieth century, self-help/mutual aid groups for mental health issues started to emerge in growing numbers, mainly in Western societies, offering and/or advocating for alternative non-traditional forms of support, and attracted the attention of many researchers and clinicians for their unique characteristics. Among the subjects of interest are typologies of groups, helping mechanisms and benefits from participation. However, there is lack of systematic research in the area and existing studies have been largely confined to the therapeutic value of these groups instead of acknowledging their socio-political meaning and subsequent psychosocial benefits for their members like personal empowerment. The present study was conducted during the transitional years from a Conservative to a newly elected Labour Government (1996 -1998), with subsequent policy shifts taking place in the welfare sector. The purpose of the study was to explore the potential of self-help groups as part of a broader new social movement, the service user movement, focussing on the English scene. It addressed this issue examining the relevance of a group typology based on political ideology and focus of change. To test the validity of this classification for members, a set of individual characteristics and group mechanisms as well as their change through time were examined. The sample consisted of fourteen mental health selfhelp/mutual aid groups from London and South East England, with a variety of structural and organisational features. The methodology used was a combination of both quantitative (self-completion questionnaires) and qualitative techniques (analysis of written material, participant observation and interviews). Measurements were repeated after a one-year interval (Time 1N=67, Time 2 N=56). Findings showed that, indeed, political ideology of self-help/mutual aid groups provided the basis of a meaningful typology and constitutes a comprehensive way of categorising them. Group ideology was related to specific helping mechanisms and aspects of personal empowerment. Specifically, conservative and combined group members reported more expressive group processes like sharing of feelings and self-disclosure, while radical group members were more empowered and optimistic. Group identification was also associated with specific helping activities and aspects of empowerment in the three group categories. The psychosocial character of group types and the beneficial outcomes for members remained stable through time. In general, prolonged participation was reflected in greater member identification with the group and resulted in improved mental wellbeing, increased social support, companionship and optimism for the future

    Studies of strategic performance management for classical organizations theory & practice

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    Nowadays, the activities of "Performance Management" have spread very broadly in actually every part of business and management. There are numerous practitioners and researchers from very different disciplines, who are involved in exploring the different contents of performance management. In this thesis, some relevant historic developments in performance management are first reviewed. This includes various theories and frameworks of performance management. Then several management science techniques are developed for assessing performance management, including new methods in Data Envelopment Analysis (DEA) and Soft System Methodology (SSM). A theoretical framework for performance management and its practical procedures (five phases) are developed for "classic" organizations using soft system thinking, and the relationship with the existing theories are explored. Eventually these results are applied in three case studies to verify our theoretical development. One of the main contributions of this work is to point out, and to systematically explore the basic idea that the effective forms and structures of performance management for an organization are likely to depend greatly on the organizational configuration, in order to coordinate well with other management activities in the organization, which has seemingly been neglected in the existing literature of performance management research in the sense that there exists little known research that associated particular forms of performance management with the explicit assumptions of organizational configuration. By applying SSM, this thesis logically derives some main functional blocks of performance management in 'classic' organizations and clarifies the relationships between performance management and other management activities. Furthermore, it develops some new tools and procedures, which can hierarchically decompose organizational strategies and produce a practical model of specific implementation steps for "classic" organizations. Our approach integrates popular types of performance management models. Last but not least, this thesis presents findings from three major cases, which are quite different organizations in terms of management styles, ownership, and operating environment, to illustrate the fliexbility of the developed theoretical framework

    Reforming the United Nations

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    The thesis deals with the financial crisis that the United Nations faced starting in 1985 when the US Congress decided to withhold a significant part of the US contribution to the UN regular budget in order to force a greater say for the major contributors on budgetary issues, budgetary restraint and greater efficiency. The UN responded by the adoption of resolution 41/213 of 19 December 1986 that was based on the recommendations of a Group of High-level Intergovernmental Experts ("G-18") set up a year earlier. A new system was introduced regarding the formulation of the regular budget of the United Nations Organisation and a broader process of reform was initiated including a restructuring of the Secretariat and of the intergovernmental machinery in the economic and social fields. After an introductory chapter (Chapter I), the thesis examines the UN problems at the budgetary/financial and administrative/structural levels, the solutions proposed from within and without the United Nations established framework and the actual attempts at reform (Chapters II and ifi). The realisation that the implementation of reforms is rather disjointed and often unsuccessful (e.g. the failure to restructure the intergovernmental machi.neiy) prompts a search for the deeper causes of the UN problems at the political level and the attitudes of the main actors, namely the USA, the USSR, some up-and-coming states, notably Japan, the Third World states and, finally, of the UN Secretary-General and the Secretariat (Chapter 1V). Although the financial crisis may have subsided since 1988 and the USA seem committed to paying up their dues, the deeper UN crisis of identity has not been resolved and is expected to resurface if no bold steps are taken. In that direction, some possible alternative courses for the UN in the future are discussed drawing upon theory and practice (Chapte
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