18,909 research outputs found
Application of Multichannel Active Vibration Control in a Multistage Gear Transmission System
Gears are the most important parts of rotating machinery and power transmission devices. When gears are engaged in meshing transmission, vibration will occur due to factors such as gear machining errors, meshing rigidity, and meshing impact. The traditional FxLMS algorithm, as a common active vibration algorithm, has been widely studied and applied in gear transmission system active vibration control in recent years. However, it is difficult to achieve good performance in convergence speed and convergence precision at the same time. This paper proposes a variable-step-size multichannel FxLMS algorithm based on the sampling function, which accelerates the convergence speed in the initial stage of iteration, improves the convergence accuracy in the steady-state adaptive stage, and makes the modified algorithm more robust. Simulations verify the effectiveness of the algorithm. An experimental platform for active vibration control of the secondary gear transmission system is built. A piezoelectric actuator is installed on an additional gear shaft to form an active structure and equipped with a signal acquisition system and a control system; the proposed variable-step-size multichannel FxLMS algorithm is experimentally verified. The experimental results show that the proposed multichannel variable-step-size FxLMS algorithm has more accurate convergence accuracy than the traditional FxLMS algorithm, and the convergence accuracy can be increased up to 123%
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The Epidemiology and Genetic Architecture of Vitamin D Deficiency in African Children
Vitamin D deficiency is a common public health problem worldwide. However, little is known about the epidemiology of vitamin D deficiency in Africa. In this thesis, I aimed to determine: 1) the prevalence of and risk factors associated with vitamin D deficiency in studies conducted in Africa; 2) the prevalence and predictors of vitamin D deficiency in African children; 3) the association between vitamin D and iron deficiency in African children; and 4) genetic variants that influence vitamin D status in Africans.
In a systematic review and meta-analyses of previous vitamin D studies in Africa, the average prevalence of low vitamin D status was 18.5%, 34.2% and 59.5% using cut-offs of 25-hydroxyvitamin D (25(OH)D) levels of <30 nmol/L, <50 nmol/L and <75 nmol/L, respectively. Populations at risk of vitamin D deficiency included newborns, women, and people living in high latitudes or urban areas.
In an epidemiological study of young children living in Africa, the prevalence of low vitamin D status was 0.6%, 7.8% and 44.5% using cut-offs of 25(OH)D levels of GC2 variant of the group-specific component (GC) gene, which encodes vitamin D binding protein.
Vitamin D deficiency was also associated with 80% higher odds of iron deficiency in these children. Adjusted regression models revealed that vitamin D deficiency was associated with higher ferritin and hepcidin levels suggesting lower iron status, and reduced sTfR and transferrin levels and increased TSAT and serum iron levels suggesting improved iron status.
Genome-wide association study (GWAS) in Africans revealed genetic variants that influence vitamin D status in vitamin D metabolism genes: DHCR7/NADSYN1, CYP2R1 and GC. However, the majority of SNPs from previous European GWASs did not replicate in the current GWAS.
Findings from this thesis indicate that vitamin D deficiency is prevalent in many African populations and should be considered in public health strategies in Africa
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Co-design As Healing: Exploring The Experiences Of Participants Facing Mental Health Problems
This thesis is an exploration of the healing role of co-design in mental health. Although co-design projects conducted within mental health settings are rising, existing literature tends to focus on the object of design and its outcomes while the experiences of participants per se remain largely unexplored. The guiding research question of this study is not how we design things that improve mental health, but how co-designing, as an act, might do so.
The thesis presents two projects that were organized in collaboration with the mental health charity Islington Mind and the Psychosis Therapy Project (PTP) in London.
The project at Islington Mind used a structured design process inviting participants to design for wellbeing. A case study analysis provides insights on how participants were impacted, summarizing key challenges and opportunities.
The design at PTP worked towards creating a collective brief in an emergent fashion, finally culminating in a board game. The experiences of participants were explored through Interpretative Phenomenological Analysis (IPA), using semi-structured interview data. The analysis served to identify key themes characterising the experience of co-design such as contributing, connecting, thinking and intentioning. In addition, a mixed-methods analysis of questionnaires and interview data exploring participants' wellbeing, showed that all participants who engaged fairly consistently in the project improved after the project ended, although some participants' scores returned to baseline six months later.
Reflecting on both projects, an approach to facilitation within mental health is outlined, detailing how the dimensions of weaving and layered participation, nurturing mattering and facilitating attitudes interlace. This contribution raises awareness of tacit dimensions in the practice of facilitation, articulating the nuances of how to encourage and sustain meaningful and ethical engagement and offering insights into a range of tools. It highlights the importance of remaining reflexive in relation to attitudes and emotions and discusses practical methodological and ethical challenges and ways to resolve them which can be of benefit to researchers embarking on a similar journey.
The thesis also offers detailed insights on how methodologies from different fields were integrated into a whole, arguing for transparency and reflexivity about epistemological assumptions, and how underlying paradigms shift in an interdisciplinary context.
Based on the overall findings, the thesis makes a case for considering design as healing (or a designerly way of healing), highlighting implications at a systems, social and individual level. It makes an original contribution to our understanding of design, highlighting its healing character, and proposes a new way to support mental health. The participants in this study not only had increased their own wellbeing through co-designing, but were also empowered and contributed towards healing the world. Hence, the thesis argues for a unique, holistic perspective of design and mental health, recognizing the interconnectedness of the individual, social and systemic dimensions of the healing processes that are ignited
The interpretation of Islam and nationalism by the elite through the English language media in Pakistan.
The media is constructed and interpreted through what people 'know'. That knowledge is, forthe most part, created through day to day experiences. In Pakistan, Islam and nationalism aretwo components of this social knowledge which are intrinsically tied to the experiences of thePakistani people. Censorship and selection are means through which this knowledge isarticulated and interpreted.General conceptions of partially shared large scale bodies of knowledge and ideas reinforce,and are reinforced by, general medium of mass communication: the print and electronic media.Focusing on the govermnent, media institutions and Pakistani elites, I describe and analyse thedifferent, sometimes conflicting, interpretations of Islam and Pakistani nationalism manifest inand through media productions presented in Pakistan.The media means many things, not least of which is power. It is the media as a source ofpower that is so frequently controlled, directed and manipulated. The terminology may beslightly different according to the context within which one is talking - propaganda, selection,etc. - but ultimately it comes down to the same thing - censorship. Each of the three groups:government, media institutions and Pakistani elites - have the power to interpret and censormedia content and consideration must be taken of each of the other power holders consequentlyrestricting the power of each group in relation to the other two. The processes of thismanipulation and their consequences form the major themes of this thesis
Development and evaluation of a treatment package for men with an intellectual disability who sexually offend
Sex offending in the general population has been a focus of interest for some time due to the damaging nature of the behaviour, and the need to reduce recidivism. Theoretical and clinical advances (Finke1hor, 1986; HM Prison Service, 1996; Marshall, Anderson, & Fernandez, 1999; Serran & Marshall, 2010) in treatment for sex offenders in the general population have been extended to men with an intellectual disability at risk of sexual offending (Lindsay, 2009). The purpose of this project is to develop and evaluate the SOTSEC-ID version cftrus model. Participants are adult males from 15 different locations across England and Wales, with an intellectual disability or borderline cognitive functioning and who have committed sexual offences. A pilot study clarified assessments and procedures, and individual data over several years is presented. A qualitative study using Interpretive Phenomenological Analysis (JP A) illustrates the 'meaning making' of participants' treatment experience through six major themes. A reliability and validity study assesses the four main quantitative measures, QACSO, SAKA, SOSAS, and VESA, finding limited support for criterion validity for the SOSAS and SAKA, excellent inter-rater reli"ability for all four main measures, and good to excellent inter-rater reliability on all but the SAKA Finally, a quantitative study, in collaboration with the wider SOTSEC-ID group, uses a repeated measures design to compare the QACSO, SOSAS and SAKA across pre-group, post-group and follow. up. Significant main effects and post-hoc comparisons were in the predicted direction for all measures. A range of information on demographic, clinical and criminogenic factors including offending during treatment or follow-up are also presented. A recidivism rate of 12.3% over a year was calculated for the sample. The treatment model and collaborative framework is recommended for wider adoption
Examination of a Brief, Self-Paced Online Self-Compassion Intervention Targeting Intuitive Eating and Body Image Outcomes among Men and Women
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
In her own words: exploring the subjectivity of Freud’s ‘teacher’ Anna von Lieben
This project is inspired by Roy Porter (1985), who draws attention to the patient-shaped gap in medical history, and Rita Charon (2006), who emphasises the need to bring the patient’s narrative to the fore in the practice of medicine. The principal aim was to devise a means of accessing the lived experience of a patient who is no longer alive in order to gain an understanding of her narrative. Anna von Lieben was identified as a suitable subject as she wrote a substantial quantity of autopathographical poetry suitable for analysis and her status as Freud’s patient makes her a person of significant interest to the history of medicine.
The poems were analysed using Interpretative Phenomenological Analysis (IPA), an idiographic and inductive method of qualitative research, based on Heideggerian hermeneutic phenomenology, which explores the lived experience of individuals and is committed to understanding the first-person perspective from the third-person position.
The main findings from the IPA study reveal that Anna experienced a prolonged period of malaise, starting in late adolescence which she believed to result, at least partly, from a traumatic experience which occurred at that time. The analysis also indicates that Anna suffered from deep and lasting feelings of guilt and shame. The discovery of additional family documentation enabled me to contextualise and add substance to the findings of the IPA study. Anna’s husband’s diaries in particular reveal that Anna:
• had a severe and longstanding gynaecological disorder
• suffered from severe morphinism
• did not benefit from Freud’s treatment which seemed neither to ease her symptoms nor identify any cause
• was treated in Paris, not by Jean-Martin Charcot as previously supposed, but by a French hydrotherapist, Theodore Keller, who appears to have become a person of considerable significance in her life.
The above findings led me to investigate Anna’s comorbidities (gynaecological disease and morphinism) and to show how those could be responsible for much of the symptomatology identified by Freud as ‘hysteria’. I then explore the possibility that her psychotic-like experiences could have been iatrogenically induced by her treatment first by Keller and then by Freud. Finally, I propose a fourfold set of hypotheses as an alternative to Freud’s diagnosis of hysteria
A New Theory of Serendipity: Nature, Emergence and Mechanism
The book explores the nature, underlying causes, and the information processing mechanism of serendipity. It proposes that natural or social survival demands drive serendipity, and serendipity is conditional on the environment and the mindset, on both individual and collective levels. From Darwin’s evolution theory to Sun Tzu’s war tactics, major innovations throughout human history are unified by this key concept. In the rapidly changing world, information is abundant but rather chaotic. The adaptive power of serendipity allows people to notice treasures within this wild sea, but only for those who understand how it works. To increase the probability of encountering and attaining serendipity, one should employ the mindsponge mechanism and the 3D process of creativity, for without these frameworks, serendipity is truly an elusive target. The book also discusses methods to build environments and cultures rich in navigational and useful information to maximize the chance of finding and capitalizing on serendipity. As a skill, serendipity has a resemblance to how kingfishers observe and hunt their prey
Interactive Sonic Environments: Sonic artwork via gameplay experience
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
Metodología de intervención para trabajar ODS. Educación a través de las artes
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
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