Homogenization techniques for population dynamics in strongly heterogeneous landscapes

An important problem in spatial ecology is to understand how population-scale patterns emerge from individual-level birth, death, and movement processes. These processes, which depend on local landscape characteristics, vary spatially and may exhibit sharp transitions through behavioural responses to habitat edges, leading to discontinuous population densities. Such systems can be modelled using reaction–diffusion equations with interface conditions that capture local behaviour at patch boundaries. In this work we develop a novel homogenization technique to approximate the large-scale dynamics of the system. We illustrate our approach, which also generalizes to multiple species, with an example of logistic growth within a periodic environment. We find that population persistence and the large-scale population carrying capacity is influenced by patch residence times that depend on patch preference, as well as movement rates in adjacent patches. The forms of the homogenized coefficients yield key theoretical insights into how large-scale dynamics arise from the small-scale features

Diffusion-driven instabilities and emerging spatial patterns in patchy landscapes

Spatial variation in population densities across a landscape is a feature of many ecological systems, from self-organised patterns on mussel beds to spatially restricted insect outbreaks. It occurs as a result of environmental variation in abiotic factors and/or biotic factors structuring the spatial distribution of populations. However the ways in which abiotic and biotic factors interact to determine the existence and nature of spatial patterns in population density remain poorly understood. Here we present a new approach to studying this question by analysing a predator–prey patch-model in a heterogenous landscape. We use analytical and numerical methods originally developed for studying nearest- neighbour (juxtacrine) signalling in epithelia to explore whether and under which conditions patterns emerge. We find that abiotic and biotic factors interact to promote pattern formation. In fact, we find a rich and highly complex array of coexisting stable patterns, located within an enormous number of unstable patterns. Our simulation results indicate that many of the stable patterns have appreciable basins of attraction, making them significant in applications. We are able to identify mechanisms for these patterns based on the classical ideas of long-range inhibition and short-range activation, whereby landscape heterogeneity can modulate the spatial scales at which these processes operate to structure the populations

Becoming a Digital Humanist: An Autobiographical Nonlinear Digital Story

My CE Becoming a Digital Humanist: An Autobiographical Nonlinear Digital Story (BDH) is a six episode nonlinear digital story demonstrating the power and importance of autobiography. It tells the story of my educational journey from Princeton Theological Seminary (PTS) to Berklee College of Music in Valencia, Spain (BV). Within the story I explore the themes of race, tradition, individuality and my desired place in the academic area of the digital humanities. Through experimental music, conceptual art and basic documentation viewers are invited to decipher my personal sense of becoming and discover their own sense of self-actualization through observation of my story. This digital story has been created through the process of artistic research as related to the practice of music and music technology within the MPTI program. The six episodes are to be watched in any order viewers choose, as long as all episodes are viewed in their entirety.https://remix.berklee.edu/graduate-studies-production-technology/1046/thumbnail.jp

Moving from Page to Playground: The Challenges and Constraints of Implementing Curriculum in Ghana

The process of translating curriculum intentions into practice, that is to say moving from page to playground, is acknowledged by curriculum experts as the most critical phase of the educational change process. It often is fraught with challenges and constraints which, if not handled expeditiously, lead to implementation failure – a characteristic of most innovations and reforms in education. Drawing on the literature on curriculum implementation and using evidence from curriculum implementation studies conducted in Ghana, this paper argues that the main reasons for the failure of educational programme implementation in the country appear to be the lack of appreciation by both experts outside the school system and educators in the system of the practical imperatives and implications of the phenomenon of curriculum implementation, and, consequently, the inability to address these at the point of need. The paper further traces the roots of many of the problems that have confronted the implementation of curricula in Ghana to inadequate pre-implementation preparations, and makes recommendations for achieving successful curriculum implementation in the future. Keywords: curriculum change, curriculum implementation, educational change, implementation failure, obstacles to implementatio

Engaging with Methodological Issues in Qualitative Research: Sharing Personal Experience to Benefit Novice Researchers

In Ghana and many African countries, students in tertiary education institutions are less familiar with qualitative research methodologies, despite the legion literature on this subject and its popularity in western higher education institutions. In this paper, I share my experience on how I engaged with methodological issues in a qualitative study which I conducted. The paper seeks to demonstrate that despite the apparently messy nature of qualitative research, its characteristics, principles and defining canons are translatable from theory to practice, from rhetoric to reality, and from the pages of textbooks to the pragmatics of research. The paper aims to provide insights to novice researchers who have interest in qualitative research methodologies but feel hesitant to apply them. Hopefully, the fears of such researchers would be allayed and they would be emboldened to venture into this exciting and excellent area of research. Keywords: Credibility, positivism, post-positivism, qualitative research, research paradigm

Professionals without a Profession? The Paradox of Contradiction about Teaching as a Profession in Ghana

Today almost every worker claims to be a professional and their occupation a profession. To teachers the question of professionalism is very important; it influences the quality of education they provide for children as well as the quality of their lives as teachers. Yet, how professionalism is defined and what constitute a profession have been sites of academic and ideological struggle between union leaders, bureaucrats and academics played out in a variety of settings. This paper reports on a study that investigated teachers’ conception of professionalism and profession. It examined teachers’ views of themselves as professionals and of teaching as a profession. The research adopted a descriptive survey approach. Evidence was gathered through administering questionnaire to teachers who had undergone pre-service professional training at bachelor’s degree level, taught for at least three years and were upgrading their professional qualification to master’s degree level. It was found that while teachers saw themselves as professionals, they did not think that teaching in Ghana qualified as a full-fledged profession. This apparent ‘paradox of contradiction’ is vital knowledge for understanding individual actions by teachers and their attitude to collective actions by teacher organisations such as the Ghana National Association of Teachers and the National Association of Graduate Teachers. Keywords: profession, professional, professionalization, professionalism, teaching

Solving the Teacher Shortage Problem in Ghana: Critical Perspectives for Understanding the Issues

The problem of getting sufficient numbers of qualified teachers to staff classrooms is one of the most significant public policy issues facing many countries. In Ghana, the problem of teacher shortage has been a perennial one, necessitated by educational expansion as well as adverse socio-economic and political circumstances, and exacerbated by high attrition rate. Efforts to find a solution are still ongoing. This paper aims to contribute to the search for solutions to the teacher shortage problem in Ghana. The paper takes the view that before education policy makers think about whether to recruit more teachers or retain existing teachers, it is important that they clearly understand the complex nature of the phenomenon of teacher shortage. The paper, therefore, reconceptualises the phenomenon of teacher shortage, clarifying it by disentangling and explicating its constituent variables. It also discusses various policy options for addressing teacher shortages, and indicates the implications of those options for teaching quality and teacher status. The ultimate objective is to provide a framework for analysing the problem of teacher shortage in a more critical way so that any interventions would be more focused and appropriately targeted. Keywords: Attrition, qualified teachers, teacher demand, teacher shortage, teacher supply