Dissertations / Theses: 'Drivers of migration'

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Biagi, Bianca. "Drivers of interregional migration flows : jobs or amenities?" Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/374706/.

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McClain, Krystaal Moonchyld. "Environmental Drivers of Migration in Two Israeli Raptor Species." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440001135.

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Melvin, Forrest Leanna. "Determining the Drivers of Alaskan Inuit Migration, Arctic Alaska." Thesis, The George Washington University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10283257.

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Migration choice among Alaskan Inuit in the Arctic Alaskan region is complex and multifaceted. Migration patterns are characterized by high rates of out-migration and return migration however, the factors contributing to migration choice are more nuanced. To better understand the driving factors influencing migration a mixed methodological approach is used by incorporating statistical data analyses and informal interviews collected for Nome Census Area and North Slope Borough. Determining the socio-cultural, economic, and environmental factors influencing migration choice of Alaskan Inuit in Arctic Alaska provides insight into community resiliency and adaptability to regional experiences of social and climatic change. The results demonstrate external investments, employment opportunities, climate change, Inuit cultural practices, and family are important to Alaskan Inuit lifestyle. Results of regression analysis indicate that climate, subsistence, and modern wage economy have the most significant effect on in and out migration in Nome Census Area while in North Slope Borough cultural economy and wage economy balance, family, and external funds have the most significant impact on migration. The factor loadings impacting migration between 1991-2011 explain only 41% in Nome Census Area and 21% in the North Slope Borough. Low explanatory power of the quantitative variables underscores the importance of the non-quantitative indicators, such as importance of family and culture on return migration. Personal interviews further support that the resilience of Arctic Alaskan communities relies on the health of local economy to provide jobs, health care, and education but also on the ability to participate in cultural and familial activities which perpetuates adaptability among Alaskan Inuit.

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Dao, Thu Hien [Verfasser]. "On the fundamental drivers of international migration / Thu Hien Dao." Bielefeld : Universitätsbibliothek Bielefeld, 2018. http://d-nb.info/1169057845/34.

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Clay, Thomas Anthony. "Drivers of variation in the migration and foraging strategies of pelagic seabirds." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267809.

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The ability to move and forage efficiently plays a major role in determining the fate of individuals, and has important implications for population dynamics and ecosystem functioning. Migration is a particular type of movement strategy, whereby animals may travel remarkable distances in order to take advantage of seasonality in resource availability or to avoid arduous winter conditions; however, this can be at a cost in terms of increased mortality. Indeed, anthropogenic threats in non-breeding areas are a major cause of population declines and a better understanding of non-breeding spatial ecology is required in order to advance both ecological theory and conservation management. The recent development of animal tracking technologies, in particular light-based geolocation, has made it possible to track large-scale and long-term movements; however, there are still gaps in our knowledge, such as the links between migratory and reproductive performance, connectivity among populations and the ontogeny of migration strategies. In this thesis, I utilise multi-species and longitudinal datasets from albatrosses and petrels, some of the most mobile species on Earth, to explore the drivers of variation in movements, habitat use and foraging behaviour, and the implications for life history and conservation. In Chapter 1, I provide an overview of the key topics of this thesis. In Chapter 2, I provide quantitative recommendations of minimum sample sizes needed to track pelagic seabird migrations, using data from 10 species. In Chapter 3, I examine between- and within-population differences in the habitat preferences and distributions of albatrosses, including the relative roles of habitat specialization and intra-specific competition. In Chapter 4, I investigate the year-round movement and foraging strategies of petrels living in nutrient-poor environments. In Chapter 5, I examine potential links between foraging behaviour during the non-breeding season and reproductive senescence. In Chapter 6, I explore the ontogeny of foraging behaviour and foraging site fidelity in young albatrosses, shedding light on their “lost years” at sea. Finally, I conclude with a general discussion summarizing main findings and suggesting future work. Overall, my results highlight the complex relationships among individual traits, the environment, movements and foraging behaviour, and population dynamics across the lifespan of individuals, with implications for the conservation of this highly threatened group of species.

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Bendandi, Barbara <1980&gt. "Effects of land degradation induced migration in Africa : providing evidence on the role of climate and environmental change as drivers of migration." Doctoral thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/12869.

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Climate change and migration are closely interconnected in many parts of the world. Migration is a key way by which households cope with and adapt to rapid and slow environmental changes. Under extreme conditions of drought, economic hardship, and political instability, migration is used as a last-resort survival mechanism. Although these cases continue to happen, they are a less common form of climate-induced migration. Most migration associated with environmental and climate change does not occur under conditions of absolute distress, but of diversification, as households search for opportunities to generate new income sources and to reduce their exposure to environmental and climate related risks and hazards. This type of migration tends to be ignored and raises almost no interest in the media. However, to fully understand the dynamics of migration in less developed countries, it is essential to consider climate change and environmental degradation and increase understanding on the role they play in driving the decision to migrate. In this thesis, the author tried to address this complex subject by adopting a mix of different approaches that take in consideration the challenges and gaps in knowledge. In particular, the aim of this thesis is to provide new evidence on relationship between climatic and environmental changes and migration by: (i) adopting an inter-disciplinary approach and comparing concepts and paradigms from different academic and policy fields; (ii) elaborating a conceptual framework that shifts from the dominant focus on climate change and addresses migration as a response to gradual environmental changes, such as land degradation and natural resource depletion; (iii) producing new empirical data through a survey conducted on migrants from sub-Saharan Africa. This thesis consists of a collection of articles and is structured in three chapters, each of which contains one articles/paper. The first two articles have been co-authored, peer-reviewed and published, while the third one has been done in collaboration with the Institute for Scientific Research of the Rabat University that administered the questionnaire in Morocco under the supervision of the author. The first article is a chapter published in the book “Migration, Risk Management and Climate Change: Evidence and Policy Responses” published by Springer under the series Global Migration Issues in 2016. The title of the chapter is “Remittances for adaptation: an ‘alternative source’ of international climate finance?”. Bringing together literature on climate finance and remittances, the article analyze whether remittances could be considered as an ‘alternative’ source of adaptation finance in international climate negotiations. The second article is a on “Vulnerability and resilience in West Africa: understanding human mobility in the context of land degradation” reviews the evidence on land degradation induced migration in West Africa and explores the circumstances under which migration can actually increase the resilience of households in the face of climate and environmental change. The third article, titled “Environmental change and migration: the role of climatic and environmental conditions in the migration decision”, aims at discussing the nexus between climate/environmental change and migration by focusing on perception of the hazards and motivations for migration from an individual’s perspective. The result of the survey confirmed that, in general, climate and environmental change are important determinants of the decision to migrate, even though concurring with other major motivations. In particular, they turned out to be the most important reasons to migrate for a non-negligible number of migrants.

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Vukomanovic, Jelena. "Exurbia as Physical and Social Space: Landscape Drivers and Ecological Impacts of Amenity Migration in the New West." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293426.

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The American West, once characterized by open spaces, low population densities, and the dominance of primary sector activities, is experiencing high rates of population growth related to amenity migration. Those same natural amenities that attract migration are often degraded by housing growth and associated development; however the extent of impacts and the specific features of the environment that attract amenity migration are poorly understood. This change in land use was investigated by first examining the impacts of exurbanization on three ecosystem indicators (fire hazard, water availability, and distance effects of houses and roads) and secondly by considering the socio-cultural and aesthetic drivers of amenity migration in the Sonoita Plain, Arizona, USA. When the impacts of houses and roads on ecosystem function were considered, 98% of exurban areas were "highly" or "very highly" impacted, compared to 100% for suburban areas and 35% for rural areas. These results were striking because exurban areas have impacts on ecosystem function comparable to those of suburban areas, despite the fact that they support significantly lower population densities. The importance of privacy in the spatial distribution of exurban development was examined through GIS viewshed analysis. Desire for privacy was manifested in the home locations selected by exurbanites, with the large majority of homes located where the inhabitants see few, if any, neighbors. Scenic beauty is a common pull factor for amenity and this study examined three visual quality metrics (naturalness, visual scale and complexity) in relation to the location of exurban houses. Exurban households see significantly more vegetation, more rugged terrain, and a larger viewshed than would be expected if they were randomly distributed. There is evidence that visual complexity throughout the viewshed may be more important than seeing the very highest peaks. These results call into question the use of county-level scales of analysis for the study of landscape preferences, which may miss key landscape aesthetic drivers of preference. Amenity drivers have important implications for the distribution of development and can inform growth strategies designed to minimize negative ecological impacts and protect visual quality of the environment.

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Kabir, Ehsanul. "Unpacking Drivers of Vulnerability on Internal Migration in Areas Prone to Drought and Riverine Erosion in North-West Bangladesh." Thesis, Griffith University, 2018. http://hdl.handle.net/10072/381686.

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This dissertation examines the vulnerability of internal migrants from north-west rural Bangladesh who have had substantial experience with slow-onset forms of natural hazard. To date, the majority of the research on the vulnerability of human systems has tended to focus on the bio-physical impacts of hazards. Although the scholarly works have also contributed to the assessment of the impacts of climate change on human migration, they have provided only a limited understanding of how such groups are affected by various aspects of vulnerability. In the climate-migration research nexus, more recent studies have recognized the need to investigate how climate and environmental vulnerability could result in incremental or non-linear migration outcomes, depending on various contexts of natural hazards. In order to examine such complexities, the concept of drivers of vulnerability offers a valuable analytical alternative to indicator based methods. This approach can explain how multiple drivers can influence the livelihoods of numerous populations which are likely to vary across the contexts of natural hazards, time, and space, and between and within social groups. Little research exists to give a comprehensive understanding of the underlying drivers of vulnerability and how and why they change across the contexts of natural hazards. This study addresses this apparent gap by generating empirical knowledge on how the drivers of vulnerability influence an individual’s decision to migrate internally away from the drought prone and riverine areas of Bangladesh. This study is based on two case studies in the north-west of Bangladesh. Each case study represents one type of slow-onset natural hazard, namely drought and slow-onset riverbank erosion. While shedding light on present climate vulnerability and its significance for human mobility, this thesis breaks unexplored ground by answering research questions that involve three interconnected issues - the underlying drivers of vulnerability experienced by the socio-economically disadvantaged internal migrants and their family members, the tipping points of their migration, and the intervening social factors that potentially influence the migration decision. This study adopts a multi-method approach and answers its research questions by means of structured interviews, focus group discussions, and key informant interviews. The results illustrate in rich details the underlying drivers of vulnerability which potentially influence involuntary internal migration from the study areas. A range of drivers of vulnerability are identified and classified into five broad thematic areas including economic, institutional, infrastructural, environmental and health-and-wellbeing. Moreover, this study provides analytical details on how individuals perceive their own tipping points, after which a decision to migrate can appear unavoidable. The study demonstrates that individuals in both hazard contexts perceive their tipping points mostly in terms of unmanageable economic pressure at the household level. Additionally, the results also confirm that the presence of social networks, which mainly involve relatives, friends, and some potential employers, are helpful at bridging the gaps between geographically dispersed places and at mobilizing social capital to ease the challenges during and after migration. This thesis contributes to theory and policy by shedding light on the recurrent vulnerability issues of internal migrants in Bangladesh. First, it suggests that the vulnerability of internal migrants living in the areas studied is shaped by various drivers, as previously stated. However, the degree of influence of such drivers is disproportionately distributed between and within the two studied contexts. Second, along with internal tipping points such as household financial stress, external elements beyond household control, such as the worrying pressure of institutional microcredit default, can potentially accelerate the decision to migrate. Third, there exists a growing recognition of the limitations of the universal indicators and indices used to understand human vulnerability at the local level. This study further compared four sub-districts within the two contexts and tested whether these would show similar sets of drivers of vulnerability. This analysis concurs with some other studies that relying on a blanket approach to vulnerability measurement would mislead future researchers and have harmful policy implications. This study reveals that careful investigation of the nuances of vulnerability at the local scales can have important policy implications. It also reveals that disadvantaged groups tend to extend their coping mechanisms when the degree of vulnerability increases. Such coping mechanisms are largely associated with governmental and non-governmental development interventions at the local level. The current research cautions that, in order to avoid future challenges, there is an urgent need to develop context specific guidelines for climate adaptation. While taking climate adaptation into account, the study questions the effectiveness of some ongoing interventions at the local level, which, include groundwater based irrigation for agriculture, rural microcredit schemes, and notes the striking absence of government welfare intervention in some of the areas studied. The main implication of the research findings for policy highlights the importance of understanding the local contexts when designing and implementing interventions, rather than adopting a general approach across all contexts. Moreover, the timely and detailed information on a range of drivers of vulnerability demonstrated in this thesis should help to analyse and evaluate the various effects of existing interventions by government and non-government organizations, as previously discussed and better manage internal migration in Bangladesh, and arguably in other similar settings.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Science
Science, Environment, Engineering and Technology
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9

Urbi, Berzenn D. "The lived experience of Filipino registered nurses seeking to migrate overseas." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/118572/1/Berzenn_Urbi_Thesis.pdf.

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This research engaged in a phenomenological exploration of the experiences and motivations of Filipino nurses working in the Philippines who were seeking overseas employment. The major driver for migration was associated with living out Filipino socio-cultural values that give emphasis to reciprocal relations with families. Although participants expressed their hopes for better remuneration, their desire to support family and social affiliations remained the primary focus of their intent. The study findings may inform policy makers and workforce planning and suggest a re-visiting of policy to investigate socio-cultural drivers often neglected in the discussions of Filipino nurse migration.

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Tonial, Genny, and Gaia Agnetti. "The Returning Indian Diaspora : Exploratory Research on Indian Return Migration Drivers and potential Effects on Firms’ Performance and Country’s Development." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176189.

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This research investigates the drivers that pushed Returned Non Resident Indians(RNRIs) to come back to their homeland and their potential contribution, through the knowledgeand competences acquired by studying and working abroad, to the Firms that hire them.We used a qualitative method pursued through semi-structured non-standardized interviews withexperts of the topic and RNRIs. Furthermore, in order to have better insights, we looked at thebackground of the top management of 8 top IT Indian companies and at newspaper coverage.It resulted that RNRIs come back mainly to be closer to their families and because of a combinationof economic decline in the West and booming economy in India, thus leading to a better lifestyle.Moreover, we found indication of the contribution presented to Firms’ by knowledge and skills andgained interesting insights on the future trends of the Diaspora.However, our findings cannot be considered as conclusive, due to the small size of the sample wehad access to. The research topic needs further research.

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Sheehan, Meghan Marie. "Determining Drivers for Wildebeest (Connochaetes taurinus) Distribution in the Masai Mara National Reserve and Surrounding Group Ranches." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1452550498.

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Aboulsamh, Mohammed A. "Model-driven data migration." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:44ddbf8b-a6a0-4830-baeb-13b2c746802f.

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Information systems often hold data of considerable value. Their continuing development or maintenance will often necessitate evolution of the system and migration of the data from one version to the next: a process that may be expensive, time-consuming, and prone to error. That such a process remains a source of challenges, is recognized by both academia and industry. In current practice, data migration is often considered only in the later stages of development, leaving critical data to be transformed and loaded by hand-written scripts, long after the design process has been completed. The advent of model-driven engineering offers an opportunity to consider the question of information system evolution and data migration earlier in the development process. A precise account of the proposed changes to an existing system model can be used to predict the consequences for existing data, and to generate the necessary data migration implementation. This dissertation shows how automatic data migration can be achieved by extending the definition of a data modeling language to include model level operations, each of which corresponds to the addition, modification, or deletion of a model component. Using the Unified Modeling Language (UML) notation as an example, we show how the specification of these operations may be translated into an abstract program in the Abstract Machine Notation (AMN), employed in the B-method, and then formally checked for consistency and applicability prior to translation into a concrete programming notation, such as Structured Query Language (SQL).

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Tang, Jialong. "What drives migration and who migrates : migration selectivity in the late 1990s in China /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?SOSC%202005%20TANG.

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Jovanovikj, Ivan [Verfasser]. "Validation of software migration : model-driven co-migration of test cases / Ivan Jovanovikj." Paderborn : Universitätsbibliothek, 2020. http://d-nb.info/1226097316/34.

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Greenwood, Erin, Sabrina Maisel, David Ebertz, Atlantis Russ, Ritu Pandey, and Joyce Schroeder. "Llgl1 prevents metaplastic survival driven by epidermal growth factor dependent migration." IMPACT JOURNALS LLC, 2016. http://hdl.handle.net/10150/622116.

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We have previously demonstrated that Llgl1 loss results in a gain of mesenchymal phenotypes and a loss of apicobasal and planar polarity. We now demonstrate that these changes represent a fundamental shift in cellular phenotype. Llgl1 regulates the expression of multiple cell identity markers, including CD44, CD49f, and CD24, and the nuclear translocation of TAZ and Slug. Cells lacking Llgl1 form mammospheres, where survival and transplantability is dependent upon the Epidermal Growth Factor Receptor (EGFR). Additionally, Llgl1 loss allows cells to grow in soft-agar and maintain prolonged survival as orthotopic transplants in NOD-SCID mice. Lineage tracing and wound healing experiments demonstrate that mammosphere survival is due to enhanced EGF-dependent migration. The loss of Llgl1 drives EGFR mislocalization and an EGFR mislocalization point mutation (P667A) drives these same phenotypes, including activation of AKT and TAZ nuclear translocation. Together, these data indicate that the loss of Llgl1 results in EGFR mislocalization, promoting pre-neoplastic changes.

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Kirsh, David Robert. "Simulations of planet migration driven by the scattering of smaller bodies." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/683.

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Zatulovskiy, Evgeny. "Bleb-driven chemotaxis in Dictyostelium discoideum." Thesis, University of Cambridge, 2013. https://www.repository.cam.ac.uk/handle/1810/244505.

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Migrating cells have two basic ways of extending their leading edge: by dendritic actin polymerization beneath the membrane, or by fluid pressure, which produces blebs. Most cells are believed to move using actin-driven projections, but in more physiological conditions, blebbing motility is also apparent. It has been shown that certain cells even can switch between these two modes of motility, although it is not known how this switch is triggered. Besides, it is unclear whether blebbing can be regulated by chemotactic stimuli, and generally, how blebbing is controlled in the cell. In this study I employed a popular model organism – Dictyostelium discoideum – to investigate the role of blebbing in chemotaxis. Here I confirm that in standard conditions Dictyostelium cells move by a combination of F-actin-driven protrusions and blebs. Blebbing is characterized by the rapid projection of hemispherical patches of plasma membrane at 2-4 times the speed of an actin-driven projection, and leaves transient scars of F-actin marking the original cortex in the base of blebs. I demonstrate that Dictyostelium cells can adjust their mode of movement according to the conditions: in a resistive environment they switch almost entirely to “bleb mode”. I show that in chemotaxing cells, blebs are mainly restricted to the leading edge, and they often lead the way when a cell is forced to re-orientate. Bleb location appears to be controlled directly by chemotactic gradients. To investigate how chemoattractant induces blebbing, I have screened signal transduction mutants for altered blebbing. I have found that blebbing is unaffected in many chemotactic mutants, but unexpectedly depends on PI3-kinases and two downstream PIP3-binding proteins of unknown function – PhdA and CRAC. I conclude that Dictyostelium cells move using a hybrid motor in which hydrostatic pressure-driven bleb formation is as important as F-actin-driven membrane extension, and that cells can change the balance between modes as required. I propose that blebbing motility of Dictyostelium cells is a direct response to mechanical resistance of environment. More generally, bleb-driven motility may be a ‘”high-force” mode of movement that is suited to penetrating tissues. Blebs are chemotactic and their induction may involve branches of the chemotactic signal transduction pathway distinct from F-actin regulation.

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Ford, Catriona Barbara. "CX3CR1/CX3CL1 axis drives the migration and maturation of oligodendroglia in the central nervous system." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29533.

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In the central nervous system, the axons of neurons are protected from damage and aided in electrical conductivity by the myelin sheath, a complex of proteins and lipids formed by oligodendrocytes. Loss or damage to the myelin sheath may result in impairment of electrical axonal conduction and eventually to neuronal death. Such demyelination is responsible, at least in part, for the disabling neurodegeneration observed in pathologies such as Multiple Sclerosis (MS) and Spinal Cord Injury. In the regenerative process of remyelination, oligodendrocyte precursor cells (OPCs), the resident glial stem cell population of the adult CNS, migrate toward the injury site, proliferate and differentiate into adult oligodendrocytes which subsequently reform the myelin sheath. Existing research indicates that OPC migration is directed by chemomigratory signals released from the site of injury and that the absence of OPCs is a feature of some MS lesions, suggesting that increased recruitment of OPCs to injury sites might improve remyelination, eventually leading to treatments of patient pathologies. I hypothesized that as yet undiscovered migration cues for OPCs might be released at sites of demyelination, diffuse through the CNS tissue, activate distal OPCs and guide them back to sites of demyelination. In this thesis, I performed bioinformatics analysis of gene expression arrays and identified upregulated cell surface receptors on OPCs activated in a cuprizone model, and upregulated secreted factors in whole lesion sites from an LPC induced MS type injury model and a Spinal Cord Injury model. I then optimised the X-celligence system for the quantification of OPC migration in response to secreted factors identified in my bioinformatics screen. By combination of these techniques with immunofluorescent staining I discovered novel expression of the cell surface receptor CX3CR1 on OPCs, increased expression of the corresponding ligand CX3CL1 in both MS type injury and Spinal Cord Injury, increased directional migration of OPCs in response to low concentrations of CX3CL1, and increased maturation of OPCs into adult oligodendrocytes at high concentrations of CX3CL1. Taken together these results propose a system in which an increasing gradient of CX3CL1 released from the site of injury directs the recruitment, then maturation of OPCs, making CX3CL1 a master regulator of OPC led CNS regeneration.

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Carruthers, Daniel J. F. "Transport modelling of secondary oil migration using gradient-driven invasion percolation techniques." Thesis, Heriot-Watt University, 1998. http://hdl.handle.net/10399/1250.

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Kramer, Edward S. "COMPUTATIONAL STUDIES OF DYNAMICS OF PRESSURE-DRIVEN DROPS IN MICRO-CHANNELS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/317.

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In particulate flows, the flow inertia impacts the motion and size distribution of the particles and this in turn, has a strong implication on global behavior of the emulsions such as their rheological properties. As such, the central goal of most of the investigations on dispersed multiphase flow, so far, has been to understand the phase distribution of particles and to correlate the global behavior of the system with this parameter. For pressure-driven particulate flows in a channel, it is known that the velocity gradient in the channel leads to a lateral force whose magnitude and direction depends on the viscosity and density ratios of the fluids and the drop deformation. This lateral (lift) force is the primary reason behind the various observed modes of phase distribution of the particles. Unfortunately, most of the studies conducted so far have been concerned with the solid particles and for flows at low to moderate Reynolds numbers. Little is known about the dynamics of deformable drops at high Reynolds numbers. The goal of this study is to bridge the gap by direct numerical simulations. A front tracking/finite difference technique is used to solve the Navier-Stokes equations in the fluids inside and outside of the drops. Initially, the drops are randomly distributed in the computational domain their evolutions are followed for a sufficiently long time so that the system reaches a quasi-steady state. The statistics about the flow then will be extracted. The flow inertia is increased incrementally by increasing the pressure gradient.

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Paterson, Chay Giles Blair. "Minimal models of invasion and clonal selection in cancer." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/28986.

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One of the defining features of cancer is cell migration: the tendency of malignant cells to become motile and move significant distances through intervening tissue. This is a necessary precondition for metastasis, the ability of cancers to spread, which once underway permits more rapid growth and complicates effective treatment. In addition, the emergence and development of cancer is currently believed to be an evolutionary process, in which the emergence of cancerous cell lines and the subsequent appearance of resistant clones is driven by selection. In this thesis we develop minimal models of the relationship between motility, growth, and evolution of cancer cells. These should be simple enough to be easily understood and analysed, but remain realistic in their biologically relevant assumptions. We utilise simple simulations of a population of individual cells in space to examine how changes in mechanical properties of invasive cells and their surroundings can affect the speed of cell migration. We similarly examine how differences in the speed of migration can affect the growth of tumours. From this we conclude that cells with a higher elastic stiffness experience stronger resistance to their movement through tissue, but this resistance is limited by the elasticity of the surrounding tissue. We also find that the growth rate of large lesions depends weakly on the migration speed of escaping cells, and has stronger and more complex dependencies on the rates of other stochastic processes in the model, namely the rate at which cells transition to being motile and the reverse rate at which cells cease to be motile. To examine how the rates of growth and evolution of an ensemble of cancerous lesions depends on their geometry and underlying fitness landscape, we develop an analytical framework in which the spatial structure is coarse grained and the cancer treated as a continuously growing system with stochastic migration events. Both the fully stochastic realisations of the system and deterministic population transport approaches are studied. Both approaches conclude that the whole ensemble can undergo migration-driven exponential growth regardless of the dependence of size on time of individual lesions, and that the relationship between growth rate and rate of migration is determined by the geometrical constraints of individual lesions. We also find that linear fitness landscapes result in faster-than-exponential growth of the ensemble, and we can determine the expected number of driver mutations present in several important cases of the model. Finally, we study data from a clinical study of the effectiveness of a new low-dose combined chemotherapy. This enables us to test some important hypotheses about the growth rate of pancreatic cancers and the speed with which evolution occurs in reality. We test a moderately successful simple model of the observed growth curves, and use it to infer how frequently drug resistant mutants appear in this clinical trial. We conclude that the main shortcomings of the model are the difficulty of avoiding over-interpretation in the face of noise and small datasets. Despite this, we find that the frequency of resistant mutants is far too high to be explained without resorting to novel mechanisms of cross-resistance to multiple drugs. We outline some speculative explanations and attempt to provide possible experimental tests.

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Tydesjö, Amanda. "Individuella migrationsdrivkrafter i den moderna svenska emigrationen : En studie om vilka faktorer som ligger bakom utlandssvenskars emigration och permanenta bosättning i USA." Thesis, Linnéuniversitetet, Institutionen för samhällsstudier (SS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-101248.

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This thesis considers the individual drivers of migration in modern Swedish emigration and the subsequent decision to remain in the host country. The study draws on primary data from 14 semi-structured digital interviews with Swedes who have emigrated and permanently settled down in different locations in the United States. Through the push- and pull framework, individual cases have been considered whilst also comparing the findings with previously identified drivers in migration research. The sociological findings of this study present the collectivist Swedish norm Jantelagen (‘The Law of Jante’) as a prospective push-factor in both the decision to emigrate and to permanently settle down in the U.S. Subsequently, certain discrepancy exists on the macro level of Swedish society as both radically individualistic with collectivistic norms expecting individual conformity. The result implies that emigration is an option to break free from normative restrictions for certain individuals. Relatedly, the perception of a negative political development, restricted freedom of opinion, and self-censoring political correctness are explicit push-factors for some Swedes to emigrate and/or reside permanently. Furthermore, higher levels of stimulation in education and work, easy access to the job and housing market in the U.S. could be linked to the migration driver subjective well-being/happiness. Network often influenced the emigration and led to perceived lifestyle improvement. Moreover, the initial push and pull factors proved to be inconstant as motives and circumstances in the migration process changed e.g. in case of separation from a partner.

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Giles, James. "The role of platelet-derived interleukin-1 alpha as a driver of neutrophil migration in vivo." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-plateletderived-interleukin1-alpha-as-a-driver-of-neutrophil-migration-in-vivo(8097504b-42c5-40c3-a18c-419bf79ebfb8).html.

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Neuroinflammation is an important contributor to the pathogenesis of many neurological diseases. A key component of the innate immune response in the central nervous system is the migration of neutrophils into the brain parenchyma, where they exacerbate neuronal injury and worsen clinical outcome. A greater understanding of the mechanisms underlying neutrophil influx into the brain may aid the development of novel therapeutic interventions for the variety of diseases to which neutrophils contribute, notably including stroke and epilepsy. In vitro evidence implicates the pro- inflammatory cytokine, interleukin-1α (IL-1α), derived from platelets as a key mediator of cerebrovascular inflammation and neutrophil migration across brain endothelial cells.The aim of the work in this thesis was to test if this mechanism is important in vivo.We investigated the contribution of platelets and IL-1 in a murine model of neutrophil migration into the peritoneal cavity in response to injection of lipopolysaccharide (LPS). Depletion of platelets abrogated the migration of neutrophils in response to LPS- induced peritonitis, indicating an important role for platelets in the process. Genetic knockout of IL-1 had no effect on neutrophil influx, demonstrating that migration in the peritoneum occurs independently of IL-1.The discovery that neutrophil migration in LPS-induced peritonitis was independent of IL-1 contrasted with the finding that platelet-derived IL-1 was a mediator of neutrophil influx across mouse brain endothelial cells in vitro. The question arose as to whether IL-1 was required as a mediator of neutrophil migration in extra-cerebral tissues. Hence, we tested the contribution of platelets and IL-1 in two further in vivo models of neutrophil migration: LPS injection into a subcutaneous air pouch, and acute lung injury induced by LPS inhalation. Platelet depletion significantly reduced neutrophil migration into the air pouch in response to LPS, yet had no effect in acute lung injury. This indicated that neutrophil migration into the air pouch was dependent on platelets, and that migration into the lungs was platelet-independent. LPS induced the same degree of neutrophil migration in wild-type and IL-1 knockout mice, demonstrating that IL-1 was not required for neutrophil migration in either model.To determine the contribution of platelets and IL-1 to neutrophil migration in response to cerebrovascular inflammation, we injected LPS into the mouse striatum. In this model, neutrophil influx to the brain parenchyma in response to LPS was reduced by depletion of circulating platelets, and inhibition of the platelet adhesion molecule, GpIb. Genetic knockout of IL-1α significantly reduced the number of invading neutrophils induced by LPS. These data confirmed that both platelets and IL-1α were important contributors to cerebral neutrophil migration in vivo. To determine whether platelets in systemic circulation may be the source of IL-1α, we treated mice with IL-1 receptor antagonist or anti-IL-1 antibodies to block systemic IL-1 action. Neither intervention affected cerebral neutrophil migration in response to LPS, suggesting that the IL-1α that mediates neutrophil migration may originate in the brain.Overall, these data demonstrate that IL-1α and platelets make an important contribution to neutrophil migration to the brain, yet independently of each other. Our data also suggest there may be specific mechanisms driving innate immune responses in vivo even in response to the same inflammatory stimulus.

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Kowalczyk, Krzysztof, and Anna Kwiecinska. "Model-Driven Software Modernization." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4643.

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This thesis elaborates the Model-Driven Software Modernization (MDSM), that has been identified by us, and is defined as a group of approaches toward modernization of legacy code. MDSM approaches are based on models, tools and processes known from the Model-Driven Engineering (MDE) that aims in automation of modernization process. This thesis describes identified MDSM approaches and related standards. Additionally, it suggests that certain kinds of modernization can be implemented in a more efficient way, when a new approach, that has been proposed by the authors, is used. An exemplary modernization, that solves selected industry problem, is implemented to demonstrate that the alternative approach is feasible. In addition, the availability of tools for MDA, which can be adopted in MDSM process, is discussed and guidelines for implementing MDSM are proposed.

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Bruyere, Blandine. "Une aventure humaine : la migration : approche des processus inconscients prémigratoires." Thesis, Lyon 2, 2014. http://www.theses.fr/2014LYO20072/document.

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Migration, exil, déportation, transplantation, exode, expatriation, autant de mots pour qualifier le départ d’un pays. Autant les sciences sociales se sont attachées à comprendre la migration sous toutes ses formes depuis longtemps, autant la psychologie « de la migration » n’en est qu’à ses débuts. Elle s’est, pour l’heure, surtout intéressée aux difficultés rencontrées par les immigrés, mais peu à l’émigré.Il est donc question dans ce travail de tenter de mettre à jour les processus psychiques, et dynamiques préalables au départ. Pour ce faire, j’ai choisi de me mettre également en situation de migration pendant le travail de la recherche, pour rencontrer, accompagner et prendre en charge des candidats aux départs, et des migrants en situation de transit. S’est révélé, au cours de ce travail, la complexité due aux emboitements des différents espaces de réalités auxquelles chaque sujet a à faire. Malgré tout, il est possible de dire que les processus migratoires se mettent en place à partir de contextes tyranniques (familiaux, sociaux) au sein desquels l'emprise et la violence sont au cœur du lien. Le prétexte économique, souvent mis au premier plan, vient symboliser la dualité dette / réparation de la dette, et semble consécutif au fantasme de meurtre qui agite le groupe familial. La migration manifeste une forme de libido d'expression épistémophilique. Elle est la mise en acte d'une quête de sens sur la jouissance de l'autre, parent, de la violence qu'il a agie en tyrannisant le groupe. La migration est métaphore, mais elle est aussi symptôme ; elle est à la fois tentative de mise en conflit par le déplacement de l’originaire aliénant, et répétition par retournement de mécanismes de rejet, d’exclusion
Migration, exile, deportation, transplantation, exodus, expatriation are as many words to describe leaving a country. Though for a long time, social sciences have been attempting to understand all forms of migration, migration psychology is starting out. Up to now, it was interested in studying the immigrant's difficulties more than the emigrant.This study tries to update the psychic and dynamic process preliminary to departure. This is why I deliberately became a migrant during the whole research: I encountered, accompanied and took in charge prospective and transit migrants.My work enlightened on the complexity due to the diverse and intricate spaces of realities each subject has to deal with.However, migratory processes can be described as induced by oppressive contexts (in family or society) where control and violence are at the core of the bond. Economic motives are often put forward: they symbolize the duality of debt and reparation, and seem to be resulting from the murder fantasy in the family group.Migration denotes a form of libido and of epistemophilic drive. It is the actuation of a quest for the meaning of the other's (the parent's) narcissistic pleasure; it questions the violence and the control the other exerts over the group.Migration is both a metaphor and a symptom; it is the attempt to challenge and to modify the original alienation, as well as a repetition and a reversal of mechanisms of rejection and exclusion

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Lee, Eunjee. "Impacts of meteorology-driven seed dispersal on plant migration : implications for future vegetation structure under changing climates." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/69469.

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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 164-169).
As the impacts among land cover change, future climates and ecosystems are expected to be substantial (e.g., Feddema et al., 2005), there are growing needs for improving the capability of simulating the dynamics of vegetation structure across the global landscape as accurately as possible. In order to serve these needs, Dynamic Global Vegetation Models (DGVMs) are used to describe the current status of vegetation structure and biogeography as well as estimate their future dynamics, either with prescribed climates or coupled to climate models. Yet, current DGVMs generally assume ubiquitous availability of seeds and do not generally consider seed dispersal mechanisms and plant migration processes, which may influence the impacts of vegetation structural changes on the climate system (i.e., change in albedo, runoff, and terrestrial carbon sequestration capacity). For the first time, this study incorporates time-varying winddriven seed dispersion (i.e., the SEED configuration) as a dynamic constraint to the migration of natural vegetation in the Community Land Model (CLM)-DGVM. Compared to estimates of satellite-derived tree cover, simulations by this model configuration shows significantly improved representation of boreal forests in Western Siberia and temperate forests in Eastern Europe. The prevailing wind pattern, along with the existing vegetation structure in nearby grid cells, alters the competition dynamics of the trees in these regions by filtering unrealistic plant functional types through adjustment of establishment rates. The SEED configuration was applied to project future vegetation structures under two climate mitigation scenarios (No-policy vs. 450ppm CO 2 stabilization) for the 21st century. The simulation results indicate that regional changes of vegetation structure under changing climates are expected to be significant. In the high latitudes, regions such as Alaska and Siberia are expected to experience substantial shifts of forestry structure, characterized by expansion of needle-leaf boreal forest and shrinkage of C3 grass Arctic. In the mid-latitudes, temperate trees are likely to expand in South America, South Africa, and East Asia at the expense of C3 grass during the latter part of the 21' century. In the Tropics, the most notable degree of change is in the composition of tropical trees and C4 grasses in the Amazon and in Africa.
(cont.) The vulnerability assessment suggested by this study shows that vegetation structures in Alaska, Greenland, Central America, southern part of South America, East Africa and East Asia are susceptible to changing climates, regardless of the two climate mitigation scenarios. Regions such as Greenland, Tibet, South Asia and Northern Australia, however, may substantially alleviate their risks of rapid change in vegetation structure, given a robust greenhouse gas stabilization target. The impacts of future vegetation change on radiation budget cannot be neglected. The results of this study suggest that depending upon the climate mitigation scenarios, vegetation change may enhance or mitigate the anticipated warming trend of the 21St century. Proliferation of boreal forests in the high latitudes to amplify the warming trend (i.e., a positive feedback to climate) if no mitigation policy is implemented. In contrast, under the 450ppm scenario, changes in vegetation structure may reduce the rate of warming, which is a negative feedback to climate. A series of hydrologic processes including interception of rainfall by forest canopy, evapotranspiration, and runoff are also influenced by modifications in vegetation structure. The magnitude of the runoff response by the vegetation change is not projected to exceed the direct response of hydrology to climate change (i.e., changes in precipitation); however, the spatial pattern of changes in runoff associated with vegetation changes indicates that vegetation change may in some regions offset or lessen increases in runoff due to enhanced precipitation under climate warming. Reduction of terrestrial productivity and a conservative estimate of vegetation carbon storage (-8PgC/yr and 24PgC, respectively under the no policy scenario) in the 21st century may be due to ignoring the CO₂ fertilization effect and partially applying the new SEED configuration to project future vegetation structures. The SEED configuration developed in this study may serve to more comprehensively represent future vegetation structure across the global landscape and therefore may provide a tool to better assess the impacts of natural vegetation dynamics on the climate system. This model configuration may also provide outputs that can be used to assess the impacts of climate change on the goods and services that ecosystems provide to society.
by Eunjee Lee.
Sc.D.

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Bjellerup, Victoria, and Lisa Bäckström. "Pendeltåg och digital dialog driver grön våg : En fallstudie över hur samhällsutveckling har påverkat kontraurbanisering i Uppsala län." Thesis, Uppsala universitet, Kulturgeografiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447788.

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This thesis has studied urban to rural migration, often referred to as counterurbanisation. The study has adapted a mixed method where quantitative statistical data has been complemented with a qualitative interview study. The quantitative results have established to what extent counterurbanization movements flow in Uppsala County. The quantitative results show small flows of migrants, which the qualitative results verify. The study has also investigated people's motivations for the move to more rural areas to determine aligned motives. The results show that the motives are more or less the same as in previous studies and can be summarized in the motivational factors, economy, structure, and behavior. Furthermore, the study has also identified enabling factors that facilitate people's possibility to move to rural areas. The results show that the last decades fast digital and infrastructural development has had an impact on this possibility, where commuting, road network, growing rural communities, internet and remote work are the most crucial enabling factors.

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Brückner, David [Verfasser], and Chase [Akademischer Betreuer] Broedersz. "Stochastic dynamics of migrating cells : a data-driven approach / David Brückner ; Betreuer: Chase Broedersz." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/123654403X/34.

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Dai, Wenbin. "On migration of scan cycle based PLC programs to distributed component-based event driven software architecture with semantic correctness assurance." Thesis, University of Auckland, 2012. http://hdl.handle.net/2292/19374.

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In current automation world, majority of systems are designed using programmable logic controllers (PLC) under the IEC 61131-3 standard. The IEC 61131-3 standard PLCs are struggling with increasing demand for reconfigurability and flexibility in distributed control systems. The IEC 61499 standard is considered as the key of enabling distributed and intelligent control into industrial automation. However, the use of the IEC 61499 standard in the automation industry is still minimal. Although advantages of replacing legacy systems with function block controlled systems are substantial, the learning curve is quite steep and the cost of required research and development is high. Introducing the IEC 61499 standard into the IEC 61131-3 based systems provides flexibility and reconfigurability as well as a better graphical view of system designs. Therefore it is important to provide an easy migration path for existing PLC programs into IEC 61499 compliant platforms as the first step towards widespread adoption of the new standard. This research presented in this thesis proposes a new methodology of migration from IEC 61131-3 PLCs to IEC 61499 function blocks. The aim of this migration process is to recreate IEC 61131-3 applications in IEC 61499 implementations with equivalent execution behaviour. The formal model of the IEC 61131-3 standard and formal cyclical execution model is included. This method also creates a foundation for correct-by-design development tools and automatic migration between the IEC 61131-3 and the IEC 61499 standards. Formal migration rules based on ontology mappings, restoring execution model including tasks and programs scheduling and variables mapping with different access levels are also provided. A transformation engine for import PLC code in XML format, mapping from PLC ontology model to Function Block model and code generation is implemented based on an ontological knowledge base and semantic query-enhanced web rule language. This research also proposes a new approach for semantic analysis using multiple-layered ontological knowledge base and rule-based configurable engine. The semantic rules of the IEC 61499 standard are proposed.

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Tebboth, Mark. "Exploring mobility and resilience in the context of climatically driven environmental change : a case study of migration in Anhui Province, China." Thesis, University of East Anglia, 2015. https://ueaeprints.uea.ac.uk/53454/.

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This thesis explores links between mobility and resilience in the context of climatically driven environmental change. Using two villages in Anhui Province, China as a comparative case study, this paper investigates the impact of two types of climatically driven environmental change (a flood and a drought) with a specific focus on the role of mobility. The study employs a novel conceptual framework that uses an adapted version of Leach et al’s (1999) ‘Environmental Entitlements Framework’ to understand the processes, characteristics and outputs that contribute to resilience at different levels of analysis. Through the use of this novel conceptual approach, issues of power and social heterogeneity are explored within a resilience framing, the lack of which is a common criticism of many existing resilience studies. The analysis reveals that, for both communities, those who elected to stay tended to exhibit more resilience than those who were obliged to stay, highlighting the important roles that immobility and choice play in relation to resilience. Significant tension was found between resilience and wellbeing; increases in levels of resilience did not always appear to correspond to increases in wellbeing. The research also reveals interesting inter and intra level interactions between individuals of the same household and between households and the village that threatens the very existence of the villages themselves. The thesis concludes by highlighting the importance of (im)mobility and choice as important influences on resilience, urging for a more critical and cautious use of the concept of resilience with regard to development initiatives and the highlights importance of drawing out interactions between and within different levels of analysis to aid understanding.

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Pelon, Floriane. "Fibroblastic heterogeneity and metastatic spread in breast cancers Fibroblast heterogeneity drives metastatic spread in breast cancer through distinct mechanisms." Thesis, Sorbonne Paris Cité, 2018. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=2392&f=17330.

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Les cancers du sein, premiers cancers féminins et causes aujourd’hui encore de nombreux décès, sont classés en 3 sous-types moléculaires : luminaux –les plus répandus, HER2 et triple-négatifs (TN) –les plus agressifs. Lors du diagnostic, l’envahissement des ganglions lymphatiques axillaires par les cellules tumorales est établi. Il s’agit, en plus de la classification moléculaire, d’un marqueur pronostique utilisé en clinique pour stratifier les patientes, car il informe sur le risque de développement ultérieur de métastases, cause majeure des décès à l’heure actuelle. Les tumeurs solides, et notamment les cancers du sein, sont des écosystèmes complexes comprenant de nombreux types cellulaires qui interagissent avec les cellules cancéreuses. Parmi eux, les fibroblastes associés au cancer (CAF) sont les plus abondants et participent activement à de nombreux aspects de la tumorigenèse dont la croissance, l’invasion, l’angiogenèse, l’immunosuppression. Cependant, ils constituent une population hétérogène et à ce jour, très peu d’études ont analysé cette hétérogénéité tout en la liant aux diverses fonctions décrites des CAF. Dans ce projet, nous nous sommes intéressés au rôle de cette hétérogénéité fibroblastique dans la dissémination métastatique des cancers du sein. En combinant l’étude de plusieurs marqueurs de CAF, nous avons montré que les ganglions lymphatiques envahis par les cellules tumorales sont constitués de 4 sous-populations de CAF (CAF-S1, S2, S3 et S4), similaires à celles identifiées dans les tumeurs primaires appariées. De façon intéressante, ce sont les deux sous-types de CAF myofibroblastiques (αSMA+), CAF-S1 et particulièrement CAF-S4, qui s’accumulent préférentiellement dans les ganglions métastatiques. Ils présentent les mêmes signatures transcriptomiques entre les deux localisations tissulaires (ganglions envahis et tumeurs primaires correspondantes). Or, ces deux populations CAF-S1 et CAF-S4 augmentent le phénotype invasif des cellules tumorales, en régulant des fonctions complémentaires. D’un côté, les CAF-S1 sont hautement motiles, et stimulent la prolifération, la migration, l’invasion et l’initiation d’une transition épithélio-mésenchymateuse des cellules de cancer du sein. De l’autre, les CAF-S4 sont très contractiles, capables de remodeler la matrice extracellulaire et promeuvent ainsi l’invasion et la motilité des cellules tumorales dans des systèmes en 3 dimensions. Des expériences fonctionnelles suggèrent que l’action des CAF-S1 implique CXCL12 et TGFβ tandis que celle des CAF-S4 dépend de la voie NOTCH. En accord avec ces résultats, l’accumulation des CAF et leur identité dans les ganglions envahis constituent deux nouveaux facteurs pronostics dans les cancers du sein, indépendants du sous-type de cancers du sein et de l’envahissement ganglionnaire. En effet, un fort contenu en CAF-S4 y est associé avec un développement ultérieur de métastases à longue distance. Ainsi, analyser le contenu fibroblastique des ganglions axillaires au diagnostic pourrait constituer une information nouvelle et utile à la prise en charge des patientes
Breast cancers are the most common cancers in women and despite great improvements in treatments, they are still responsible for many deaths worldwide. They are classified into 3 main molecular subtypes: Luminal cancers are the most frequent ones, while HER2 and TN are the most aggressive. At diagnostic, lymph node involvement is also assessed as it constitutes, in addition to molecular classification, a strong prognostic marker. Indeed, it informs on the risk to develop further distant metastases, which is the main cause of death by cancer. Solid tumors, including breast cancers, are complex ecologies comprising numerous different cell types that interact with cancer cells. Among them, cancer-associated-fibroblasts (CAF) are the most abundant and actively participate in many tumor hallmarks such as tumor growth, invasion, immunosuppression and angiogenesis. However, they do not constitute a homogeneous population but so far, only few studies have characterized this heterogeneity and linked it to CAF previously described functions. In this project, we focused on the potential involvement of CAF heterogeneity in breast cancer metastatic spread. Combining the analysis of several CAF markers, we showed that invaded LN comprise 4 CAF subsets (CAF-S1, S2, S3 and S4), similar to those found in primary tumors. Interestingly, the two myofibroblastic subsets (αSMA+) CAF-S1 and especially CAF-S4 preferentially accumulate in metastatic LN and present the same transcriptomic profiles in both tumors and LN. Importantly, both CAF-S1 and CAF-S4 display pro-invasive properties, by acting at different levels on tumor cells. On the one hand, highly motile CAF-S1 stimulate breast cancer cell proliferation, migration and EMT initiation. On the other hand, CAF-S4 exhibit an important contractility and by remodeling the matrix they are able to promote tumor cell invasion in 3D. Functional studies highlight a CXCL12/TGFβ involvement in CAF-S1 functions while CAF-S4 pro-invasive phenotype appears to be Notch-dependent. In agreement with these data, we found that CAF accumulation and subset enrichment in involved LN were two new prognostic factors, independent of breast cancer molecular subtypes and LN status at diagnosis. Indeed, stromal rich LN with a predominance of CAF-S4 are associated with long distance metastases development and poor overall survival. Thus, we propose that analyzing LN fibroblastic content at diagnosis could constitute new and useful information to breast cancer patients’ care

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Helgesen, Hans Kristian. "Anisotropic depth migration of converted wave data, inversion of multicomponent data to estimate elastic parameters at the seafloor and one-dimensional data-driven inversion." Doctoral thesis, Norwegian University of Science and Technology, Department of Physics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2286.

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The increasing demand for oil and gas in the world today drives the need for new and improved methods for identifying hydrocarbon prospects. The petroleum industry uses information about the subsurface in the exploration and production of oil and gas. The industry's tendency to explore deeper waters and more geologically complex areas requires reliable and more robust methods for extracting such information.

This thesis illustrates possible strategies for using seismic reflection data in the inversion for subsurface earth properties. One strategy which is the traditional approach in seismic is to consider inversion as a stepwise procedure consisting of a model-driven global reflectivity imaging process (migration) followed by target-related elastic inversion of the reflectivity information into earth property parameters.

In this thesis a method describing wave equation prestack depth migration of converted wave data in anisotropic media is presented. The migration is accomplished by numerical wavefield extrapolation in the frequency-space domain using precomputed space-variant fillter operators. Imaging is performed by crosscorrelating the source wavefield with the data wavefield at each depth level. Data examples demonstrate good dip response and correct kinematic behavior and illustrate the method's ability to handle complex multi-layer models with a relatively high degree of anisotropy.

By considering seismic inversion as a stepwise approach, this thesis also presents a method for inversion of reflection information into medium parameters. The method provides estimation of density and P-wave and S-wave velocities at the seafloor by inversion of the acoustic-elastic PP reflection coefficient estimated at the seafloor. The PP reflection coefficient is calculated in the frequency-slowness domain from seafloor measurements of the pressure and the vertical component of the particle velocity. The algorithm gives estimates of seafloor parameters in good agreement with the true model parameters.

Another strategy for using seismic data in the inversion for subsurface earth properties is to perform inversion as a data-driven procedure where the medium parameters are directly inverted for. In this thesis a new method on inverse scattering for the estimation of the medium properties of a onedimensional acoustic layered medium from single scattering data is presented. The method provides an explicit, non-iterative and fully data-driven solution of the inverse one-dimensional scattering problem.

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Song, Xiang. "Seamless mobility in ubiquitous computing environments." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24671.

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Thesis (Ph.D.)--Computing, Georgia Institute of Technology, 2009.
Committee Chair: Ramachandran, Umakishore; Committee Member: Ahamad, Mustaque; Committee Member: Edwards, Keith; Committee Member: Liu, Ling; Committee Member: Suh, Sang-bum

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Angeles, Arlou Kristina J. [Verfasser], and Holger [Akademischer Betreuer] Sültmann. "The ERG-driven long non-coding RNA LINC00920 promotes cell proliferation and migration in prostate cancer cells by modulating FOXO activity through a direct interaction with 14-3-3ε / Arlou Kristina Angeles ; Betreuer: Holger Sültmann." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1220429678/34.

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Angeles, Arlou Kristina [Verfasser], and Holger [Akademischer Betreuer] Sültmann. "The ERG-driven long non-coding RNA LINC00920 promotes cell proliferation and migration in prostate cancer cells by modulating FOXO activity through a direct interaction with 14-3-3ε / Arlou Kristina Angeles ; Betreuer: Holger Sültmann." Heidelberg : Universitätsbibliothek Heidelberg, 2020. http://d-nb.info/1220429678/34.

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36

Puyuelo, valdes Pilar. "Laser-driven ion acceleration with high-density gas-jet targets and application to elemental analysis." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0134.

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Cette thèse en cotutelle entre la France et le Canada étudie l’accélération d’ions dans l’interaction laser-plasma. La première partie, réalisée au CENBG et sur l’installation PICO2000 du laboratoire LULI à l'École Polytechnique de Palaiseau, présente des études expérimentales, complétées par des simulations numériques de type Particle-In-Cell, portant sur l’accélération d’ions dans l'interaction d'un laser infrarouge de haute puissance avec une cible gazeuse de haute densité. La seconde, réalisée avec le laser ALLS de l’institut EMT INRS, concerne le développement d'une application des faisceaux génerés par laser pour l’analyse élémentaire d’échantillons. Dans le manuscrit, les caractéristiques des deux lasers, des différents diagnostics de particules et d’X utilisés (paraboles de Thomson, films radiochromiques, CCD...) ainsi que les configurations expérimentales sont décrites.Les jets de gaz denses supersoniques utilisés comme cibles d'interaction laser au LULI, sont présentés en détail; depuis leur conception grâce à des simulations de dynamique des fluides, jusqu’à la caractérisation de leurs profils de densité par interférométrie Mach Zehnder. D'autres méthodes optiques comme la strioscopie ont été mises en œuvre pour contrôler la dynamique du jet de gaz et définir l’instant optimal pour effectuer le tir laser. Les spectres obtenus dans differentes conditions d’interaction sont présentés. Ils montrent, dans la direction du laser, des énergies maximales allant jusqu’à 6 MeV pour les protons et 16 MeV pour les ions hélium. Des simulations numériques effectuées avec le code PICLS sont utilisées pour discuter les différentes structures observées dans les spectres et les mécanismes d’interaction sous jacents.Des faisceaux de protons et d’X générés par le laser ALLS dans l’interaction avec des cibles solides d’aluminium, de cuivre et d’or ont été utilisés pour effectuer des analyses de matériaux par les méthodes Particle-induced X-ray emission (PIXE) et X-ray fluorescence (XRF). L’importance relative des deux techniques, XRF et PIXE, est étudiée en fonction de la nature de la cible d’interaction. Les deux diagnostics peuvent être implémentés simultanément ou individuellement, en changeant simplement la cible d'interaction. La double contribution des deux processus améliore l’identification des constituants des matériaux et permet une analyse volumétrique jusqu'à des dizaines de microns et sur de grandes surfaces (~cm2) jusqu'à un seuil de détection de quelques ppms
In this joint thesis, performed between the French Institute CENBG (Bordeaux) and the Canadian Institute INRS (Varennes), laser driven ion acceleration and an application of the beams are studied. The first part, carried out at CENBG and on the PICO2000 laser facility of the LULI laboratory, studies both experimentally and using numerical particle-in-cell (PIC) simulations, the interaction of a high power infrared laser with a high density gas target. The second part, performed at ALLS laser facility of the EMT-INRS institute, investigates the utilization of laser generated beams for elementary analysis of various materials and artifacts. In this work, firstly the characteristics of the two lasers, the experimental configurations, and the different employed particle diagnostics (Thomson parabolas, radiochromic films, etc.) employed are introduced.In the first part, a detailed study of the supersonic high density gas jets which have been used as targets at LULI is presented, from their conceptual design using fluid dynamics simulations, up to the characterization of their density profiles using Mach-Zehnder interferometry. Other optical methods such as strioscopy have been implemented to control the dynamics of the gas jet and thus define the optimal instant to perform the laser shot. The spectra obtained in different interaction conditions are presented, showing maximum energies of up to 6 MeV for protons and 16 MeV for Helium ions in the laser direction. Numerical simulations carried out with the PIC code PICLS are presented and used to discuss the different structures seen in the spectra and the underlying acceleration mechanisms.The second part presents an experiment using laser based sources generated by the ALLS laser to perform a material analysis by the Particle-induced X-ray emission (PIXE) and X-ray fluorescence (XRF) techniques. Proton and X-ray beams produced by the interaction of the laser with Aluminum, Copper and Gold targets were used to make these analyzes. The relative importance of XRF or PIXE is studied depending on the nature of the particle production target. Several spectra obtained for different materials are presented and discussed. The dual contribution of both processes is analyzed and indicates that a combination improves the retrieval of constituents in materials and allows for volumetric analysis up to tens of microns on cm^2 large areas, up to a detection threshold of ppms

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Arndt, Bruno Felipe. "MME-MDD : um método para manutenção e evolução de sistemas baseados no MDD." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8503.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Model-Driven Development (MDD) is proposed to reduce the semantic gap between problem and solution/implementation domains. Some tools are used, and the code generator is commonly used in this context. These generators are often implemented using templates. A Reference Implementation (RI) favoring the development/ maintenance of software facilitates this implementation’s types. However, RI requires a code migration process which consists in artifacts’ synchronization, and it is responsible for 20% to 25% of the time spent on development. The literature has no describe automatic solutions, but the group that this reaserch was included has develop tools that automate this process and reduce the time spent on some tasks. But each task has a different performance in relation to time spent, so automation of some tasks can be disadvantageous. Few reports describe such tasks and which ones are capable of automatic code migration. The aim of this study is to investigate the maintain and evolution process to identify and describe the types of maintain and evolution tasks that are essentially. Based on this study, a method (MME-MDD) that drives the developer during that proccess to guide the developer during the realization of each task, with the aim to maximize the benefits of this approach. The MME-MDD was validated by a case study and a empirical study and the method showed effective in most of tasks. In addition, studies show that using the proposed method brought a gain in the quality of the source code.
O MDD (Model-Driven Development) tem como proposta a redução da distância semântica entre os domínios problema e solução/implementação. Para isso, são utilizadas algumas ferramentas, sendo o gerador de código comumente usado neste contexto. Os geradores de código são frequentemente implementados com a utilização de templates. Para facilitar este tipo de implementação, usualmente é empregado uma Implementação de Referência (IR), favorecendo a evolução/ manutenção do software. Contudo, a IR traz a necessidade do processo de migração de código, que consiste na sincronização entre o seu código-fonte e os templates, sendo que este é responsável por 20 a 25% do tempo gasto no desenvolvimento. Na literatura não há relatos de solução automatizada, mas o grupo no qual esta pesquisa se insere vem desenvolvendo ferramentas que automatizam este processo e reduzem o tempo aplicado em algumas tarefas testadas. Porém, cada tarefa tem um desempenho diferente em relação ao tempo gasto e, portanto, a automação de algumas tarefas pode ser desvantajosa. Existem poucos relatos na literatura descrevendo tais tarefas e quais são os passos necessários para realizá-las. O objetivo deste estudo foi a investigação do processo de manutenção e evolução de sistemas baseados em MDD com a finalidade de identificar e descrever os tipos de tarefas de manutenção e evolução. Com base nesse estudo, foi elaborado o método MMEMDD que conduz o desenvolvedor durante o processo de manutenção e evolução de sistemas, visando guiar o desenvolvedor durante a realização de cada um dos tipos de tarefas, com o intuito de maximizar os benefícios da utilização dessa abordagem. O método foi validado por meio de um estudo de caso e um estudo experimental, sendo que o método se mostrou efetivo em grande parte das tarefas testadas. Além disso, os estudos apontaram que a utilização do método proposto trouxe ganho na qualidade do código-fonte.

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Possatto, Marcos Antonio. "Uma abordagem para migração automática de código no contexto do desenvolvimento orientado a modelos." Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/554.

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Universidade Federal de Minas Gerais
Code generators play a key role in model-driven software development. They are responsible for transforming high-level assets (models) into implementation assets (code). Most generators are based on templates, which are pieces of text instrumented with code expansion elements. They receive an input and produce an output according to the template's programming. To build such template-based generators, the code of an existing implementation, already tested and validated, can be used as a reference, in a process known as code migration. With software evolution and the need for changes in the code generator, the templates start to differ from this reference implementation. In order to restablish the synchronization, additional effort is required. Tackling the challenge of keeping these assets synchronized (reference implementation and templates) is this dissertation's subject. The goal is to provide some automation to the code migration process, even if partial, in order to increase productivity in the maintenance of code generators. A mechanism was developed to make it possible to automatically reproduce changes that are performed in the reference implementation into one or more code generation templates. This mechanism was evaluated through an empirical study, yielding good performance in a controlled environment. This indicates that automation can help to reduce the effort in the maintenance of code generators in a model-driven development context.
Os geradores de código desempenham um papel fundamental no desenvolvimento de software orientado a modelos. São responsáveis pela transformação dos artefatos de alto nível de abstração (modelo) em elementos de implementação (código). Os tipos mais comuns de geradores são os baseados em template. São compostos fundamentalmente por elementos de expansão de código, que recebem uma entrada e a convertem em código, conforme a programação inserida nesses templates. O código de uma implementação já testado e validado pode servir de referência para a criação de templates, por meio de um processo conhecido como migração de código. Com a dinâmica da evolução do software e a necessidade de efetuar mudanças no gerador de código ocorre a perda de sincronismo entre os templates e esse código de referência, sendo necessário um esforço adicional para mantê-los sincronizados. O desafio de manter esses artefatos sincronizados constituiu o objetivo desta dissertação de mestrado, que proporcionou ganhos de produtividade, por meio de uma automação, ainda que parcial, desse processo. Nesse sentido, foi desenvolvido um mecanismo para propagar automaticamente as alterações introduzidas no código de referência para os templates, que reduziu o tempo e facilitou a manutenção de geradores de código que sofrem com o problema da perda de sincronismo nesses artefatos. O protótipo para a migração automática de código desenvolvido nesta dissertação foi submetido a um estudo empírico, atingindo um bom desempenho com a sua utilização na maioria das tarefas de migração de código avaliadas, o que indica que a automação pode ajudar a resolver o problema e reduzir o esforço de manutenção no desenvolvimento de software orientado a modelos.

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Liang, Yu-Pei, and 梁郁珮. "Android system migration and System Drivers development on the RSX Embedded system." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/r3p3k7.

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碩士
國立清華大學
資訊工程學系所
105
Embedded systems are everywhere in our lives. Display and touch module always play the important role in many applications of embedded devices. With the development in flexible electronics technology, embedded platform has broken the previous non-bendable concept. To respond to the development of new ``soft" platform device, the flexible display technology has gradually entered the popular stage of development. Many international companies are studying these emerging technology and applications recently, such as South Korea's Samsung, LG, Japan's Sony and Taiwan's ITRI. There are many studies on this emerging application project, but they focus on the theoretical basis of some research is to further study the user interaction method design or the new type of application system design. However, a new type of application how to integrate development environment is very few paper mentioned. This thesis specifically focuses on the procedure to migrate the system for emerging application, and the successfully migrate Android system to RSX platform. In additional we also develop some kernel driver to RSX platform for integrating more applications. Hoping to through this thesis makes it easier for future to make the development environment and carry out more relevant research to make the new type of embedded system application more rapid

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Freshwater, Cameron. "Ecological drivers of variation in juvenile sockeye salmon marine migrations." Thesis, 2017. https://dspace.library.uvic.ca//handle/1828/8783.

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Animal migrations are often associated with high mortality due to increased energy expenditure, reduced foraging opportunities, and increased predation risk. Migratory traits such as body size, phenology, or use of stopover habitats may moderate individual risk to mortality mechanisms and influence patterns of survival. However, variability in migratory traits is rarely quantified in detail because tracking many individuals over large areas is logistically challenging. In this dissertation, I used otoliths to examine migratory variability among and within sockeye salmon (Oncorhynchus nerka) populations, a species that has recently experienced declines associated with poor survival during juvenile marine migrations. Broadly, I examined the individual and environmental drivers of migratory patterns, as well as how variation across ecological scales (individuals, populations, and years) contributed to migratory diversity. First, I conducted a laboratory study to validate the use of otolith microstructure techniques in sockeye salmon post-smolts. Next, I assessed how a suite of ecological processes could interact to create a latitudinal gradient in sockeye salmon body size. By reconstructing individual growth and migration histories I determined that variation in size was correlated with ocean entry size and phenology, rather than differential marine growth or size-selective mortality. I then used estimates of migratory rate from otoliths to demonstrate that juvenile sockeye salmon exhibited distinct migratory phenotypes associated with ocean entry traits. Larger individuals migrated rapidly offshore, while smaller fish reared for several weeks in nearshore regions. Furthermore, a subset of the smallest individuals entered the ocean late in the year, migrated particularly slowly, and may have overwintered on the continental shelf. These linkages between ocean entry and migratory traits suggest juvenile sockeye salmon exhibit substantial migratory plasticity associated with carry-over effects from freshwater residence; however juvenile salmon may also respond strongly to variable conditions in marine habitats. In my fifth chapter, I compared marine growth and migration phenology in years with low and high competitor densities. After accounting for freshwater density-dependent effects, growth rates were similar in both years, but mean migration rates were nearly 50% faster in the high-density year. Migratory behavior may be used to buffer individuals from the effect of competitive interactions. In my final chapter, I sampled 16 Fraser River sockeye salmon populations to explore variation in the timing and duration of early marine migrations. Although populations differed in downstream migration timing, as well as their duration of residence within nearshore habitats, there was substantial variation within each population and between sampling years. These findings suggest individual characteristics and stochastic processes interact with population-specific strategies to shape migratory phenologies in this metapopulation. Management actions should account for and preserve migratory diversity at multiple ecological scales to maintain resilient salmon populations into the future.
Graduate
2018-10-17

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CHAO, ZHOU RUI, and 周睿超. "From Farming to Driving: the Migration and Adaption of Henan Taxi Drivers in Chinese Cities." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/e9hs49.

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碩士
東海大學
社會學系
104
Abstract The emergence and flourishing of taxi services is an epitome of the development of urban life style in China in the recent 30 years. This thesis first review the evolution of taxi service in China. This industry is greatly influenced by the ideology of regime and basic economic system(public ownership/private ownership). Based on the fieldwork in four county level cities, this thesis discuss the mode of operation in taxi industry in nowadays china. The “gua-kao” mode create a field in which taxi drivers can speculate. The uncertainty of taxi license market also lead to the collective action of taxi drivers. This thesis focus on the experience of former farmer who transfer themselves into taxi driver in migration. Meanwhile, local government actively promote rigorous mass movement which aims at improving quality of taxi service. This movement also causes collective action of taxi drivers.

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Ravi, Ganesh Priya. "Geologic drivers affecting buoyant plume migration patterns in small-scale heterogeneous media : characterizing capillary channels of sequestered CO₂." 2012. http://hdl.handle.net/2152/20017.

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CO₂ sequestration aims for the most efficient utilization of reservoir pore volume and for maximizing security of storage. For typical field conditions and injection rates, buoyancy and capillary forces grow dominant over viscous forces within hundreds of meters of the injection wells as the pressure gradient from injection becomes less influential on flow processes. Flow regimes ranging from compact flow to capillary channel flow or secondary accumulation beneath a seal are possible through time as the CO₂ plume travels through the storage reservoir. Here we model the range of possible migration behavior in the capillary channel regime in small-scale domains whose heterogeneity has been resolved at depositional (sub-millimeter) scale. Two types of model domains have been studied in this work: domains with depositional fabric from real, naturally-occurring geologic samples and geostatistically generated synthetic model fabrics. The real domains come from quasi-2D physical geologic samples (peel # 1: ~1 m × 0.5 m sample and peel # 2: ~0.4 m × 0.6 m sample) that are vertically oriented relief peels of fluvial sediment extracted from the Brazos River, Texas. Peel # 1 is oriented perpendicular to dominant depositional flow while peel # 2 is a flow-parallel specimen. The various depositional fabrics represent definite correlation lengths of threshold pressures in the horizontal and vertical directions which can be extracted. High-resolution (~2 million element model) laser scanning of the samples provided detailed topography which is the result of nearly linear corresponding changes in measured grain size (normal distribution) and sorting. We model the basic physics of buoyant migration in heterogeneous domain using commercial software which applies the principle of invasion percolation (IP). The criterion for governing drainage at the pore scale is that the capillary pressure of the fluid needs to be greater than or equal to the threshold pressure of the pore throat it is trying to enter for the interface to advance into the pore. Here we employ the extension of this concept to flows at larger scales, which replaces the pore throat with a volume of rock with a characteristic value of capillary entry pressure. The fluid capillary pressure is proportional to the height of continuous column of the buoyant phase. The effects of (i) threshold pressure range, i.e. difference between the maximum and minimum threshold pressures in the domain; and (ii) the density difference between CO₂ and connate water on capillary channels of CO₂ were studied on the various sedimentologic fabrics. As the rock and fluid properties varied for different model domains, ₂ migration patterns varied between predominantly fingering and predominantly back-filling structures. Sufficiently heterogeneous media (threshold pressures varying by a factor of 10 or more) and media with depositional fabrics having high ratios of horizontal and vertical correlation lengths of capillary entry pressures in the domain yield back-filling pattern, resulting in a significantly large storage capacity. Invasion percolation simulation models give qualitatively similar CO₂ migration patterns compared to full-physics simulators in small-scale but high resolution domains which are sufficiently heterogeneous. On the other hand, we find the invasion percolation simulations predicting disperse capillary fingering pattern in relatively homogeneous media (threshold pressures varying by less than a factor of 10) while the full-physics simulations reveal a very compact CO₂ front in the same media. This stark difference needs to be investigated to understand the governing flow physics in these domains. Fingering flow pattern in the capillary channel regime would clearly result in the estimated storage capacity being much less than the nominal value (the pore volume of the rock) as the rock-fluid contact is minimal. The importance of this work lies in the verification that a relatively simple model (invasion percolation), which runs in a very small fraction of the time required by full-physics simulators, can be used to study buoyant migration in rocks at the micro-scale. Understanding migration behavior at the small-scale can help us approach the problem of upscaling better and hence define the complex plume dynamics at the reservoir scale more realistically. Knowledge of the correlation structure of the sedimentologic fabric (ratio of correlation lengths of threshold pressures in horizontal and vertical directions) and the threshold pressure distribution (permeability distribution) for any given reservoir rock could help evaluate amount of CO₂ that can be stored per unit volume of rock (storage potential) for a reservoir in the migration phase of sequestration. The possibility of predictive ability for expected capillary channel flow patterns kindles the prospect of enabling an engineered storage strategy that drives the behavior toward the desired flow patterns in the subsurface.
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Jelínek, Martin. "On the limits of labour mobility within the EU." Master's thesis, 2014. http://www.nusl.cz/ntk/nusl-329213.

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This Master thesis deals with labour mobility and aims to uncover the main drivers influencing the flows of workers within the European Union (EU). It first provides an extensive overview of labour market, labour mobility and legal framework in the EU. Then it discusses several theories and models dealing with labour mobility. The main part of this thesis consists in empirical analysis of labour flows within EU-25 countries. This analysis is meant to provide statistical evidence of relevant mobility drivers. Contrarily to similar works, this thesis takes into account not only economic and financial factors, but also social, psychological, linguistic and other non-tangible factors that might play important role in determining the labour flows within the EU. The thesis further focuses on specific mobility incentives of the Old and the New Member States. Based on results of the empirical model and the regression analysis, the thesis concludes by discussing the limits of labour mobility and suggesting a remedy aimed at enhancing it.

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Maria, Francesco De. "Potenziale migratorio come categoria di analisi della mobilità umana. Una ricerca educativa quali-quantitativa sui giovani della costa d’avorio (The migratory potential as a category of analysis of Human Mobility. A qualitative-quantitative educational research on young people of the Ivory Coast)." Doctoral thesis, 2020. http://hdl.handle.net/2158/1189902.

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L’elaborato affronta il tema della Mobilità Umana e del complesso insieme di fattori soggettivi e ambientali che possono influenzare la nascita di un’aspirazione migratoria e l’effettiva realizzazione di un progetto di migrazione. Il tema viene trattato a partire dal quadro delle strategie e delle politiche globali di sviluppo umano e in materia di gestione sostenibile dei fenomeni migratori internazionali e intra-regionali. Da una parte, si fa riferimento ad una molteplicità di tipologie di migranti e migrazioni, ognuna delle quali presenta caratteristiche che variano in base ai contesti e ai soggetti interessati; dall’altra, si guarda, con focus e priorità differenti, al coinvolgimento dei paesi di origine, di transito e di destinazione. In tal senso, il caso sulla migrazione dei giovani della Costa d’Avorio riguarda un tipo di migrazione prevalentemente economica, legata alla ricerca di migliori opportunità di vita e di lavoro. Lo studio si inserisce nell’ambito della letteratura internazionale dei Migration Studies che sviluppa il nesso tra migrazione e sviluppo, l’evoluzione dei concetti di cause, determinanti e drivers della migrazione e i concetti di aspirazione e capacità migratoria. Attraverso un approccio olistico e critico-trasformativo che (nell’ambito dell’educazione degli adulti) ha fatto da guida a tutto il lavoro realizzato e sviluppando una dimensione educativa trasversale ai processi indagati, il costrutto di potenziale migratorio viene assunto come categoria analitico-interpretativa del fenomeno della mobilità umana. La ricerca empirica (realizzata durante quattro missioni di terreno nel biennio 2017-2019) si è avvalsa di un disegno metodologico di tipo esplorativo sequenziale nell’ambito dei Mixed Method Research, in cui i dati di ricerca qualitativi sono stati funzionali alla costruzione degli strumenti di ricerca quantitativi. L’obiettivo finale è stato quello di delineare un approccio evidence based per l’analisi e la gestione del fenomeno della mobilità capace di offrire elementi utili per la costruzione di strategie e politiche da applicare in contesti con potenziale migratorio e nel settore della formazione e dello sviluppo professionale dei giovani. Questo è stato possibile attraverso la validazione dei costrutti contenuti nell’ipotesi di ricerca, la definizione dei profili migratori potenziali, la validazione di uno strumento di misurazione del potenziale migratorio e la costruzione di un modello di analisi costituito da quattro categorie principali: progetto migratorio, condizioni educative, aspirazione migratoria e potenziale di conoscenza. ENGLISH The paper faces the topic of Human Mobility and the totality of the individual and environmental factors influencing the birth of a migration aspiration and the effective realization of a migration project. The topic is debated through the framework of the strategies and global policies of human development, concerning the sustainable management of migratory phenomena, either international and intraregional. On one side, reference is made to a multiplicity of migrants and migrations, showing characteristics that vary according to contexts and subjects involved; on the other, focus and different priorities are given to the involvement of countries of origin, transit and destination. In this regard, the case on Ivory Coast young people’s migration concerns a mainly economic migration, linked to the research of better life conditions and job opportunities. The study belongs to the field of international literature of Migration Studies which creates the nexus between migration and development, the evolution of causes concepts, determinants and migration drivers such as the concepts of migration aspiration and ability. Through a holistic and critical-transformative approach that (in the area of adult education) has been the work’s guideline and developing an educational dimension, transversal to the investigated processes, the construct of migratory potential is assumed as analytic-interpretative category of the human mobility phenomena. The empiric research (realized during four field researches in the biennium 2017-2019) has employed an exploratory sequential methodologic design in the field of Mixed Method Research, where the qualitative research data were functional to build quantitative tools of research. The final objective was to delineate an evidence-based approach for the analysis and management of the mobility phenomenon, able to give useful elements to build strategies and policies to be applied in contexts with migratory potential and in the area of education and professional development of the youngest. This was made possible through the validation of constructs contained in the research hypothesis, the definition of potential migratory profiles, the validation of an instrument measuring the migratory potential and the construction of an analysis model made by four main categories: migratory project, education conditions, migration aspiration and knowledge potential.

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HUANG, LI-CHIN, and 黃麗琴. "Timing-Driven Octilinear Steiner Tree Migration." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/23578910898935667898.

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碩士
中華大學
資訊工程學系碩士班
95
It is well known that the timing-driven rectilinear Steiner tree problem for any signal net has been extensively studied and an effective timing-driven rectilinear Steiner tree has been obtained. Based on the good result in a timing-driven rectilinear Steiner tree, given a rectilinear Steiner tree(RST) for any signal net, an effective timing-driven octilinear Steiner tree(TOST) approach is proposed to transform the original RST into a timing-driven octilinear Steiner tree(OST) by using the computation of the octilinear distance and the reassignment of original Steiner points in the RST in this paper. First, the RST can be transformed into its Steiner routing tree(SRT). In this approach, based on the concept of timing-constrained routing flexibility of Steiner points, the related SRT in a rectilinear routing model can be further transformed into that in an octilinear routing model by reassigning original Steiner points onto feasible positions. Finally, the resultant SRT will lead to a timing-driven octilinear Steiner tree by using the connection of horizontal, vertical and +45ﾟ and -45ﾟ diagonal wire segments in a Steiner tree. The experimental results show that the timing-driven OSTs in the TOST approach reduce 5%-22% timing delay than the original RSTs for the tested signal nets.

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Ranjan, Supranamaya. "QoS-driven server migration for Internet data centers." Thesis, 2002. http://hdl.handle.net/1911/17544.

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Many organizations have chosen to host Internet applications at Internet Data Centers (IDCs) located near network access points of the Internet to take advantage of their high availability, large network bandwidths and low network latencies. Current IDCs provide for a dedicated and static allocation of resources to each hosted application. Unfortunately, workloads for these sites are highly variable, leading to poor resource-utilization, poor application-performance, or both. The goal of this thesis is to develop a framework for QoS-driven dynamic resource-allocation in IDCs. Termed QuID (Quality-of-Service Infrastructure on Demand), the framework's contributions are threefold. First, we develop a simple adaptive algorithm to reduce the average number of servers used by an application while satisfying its QoS-objectives. Second, we develop an optimal off-line algorithm that bounds the advantage of any dynamic policy and provides a performance benchmark. Finally, we perform an extensive simulation study using traces from large-scale E-commerce and search-engine sites.

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"Electric Field Driven Migration and Separation in the Microenvironment." Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.62691.

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abstract: Novel electric field-assisted microfluidic platforms were developed to exploit unique migration phenomena, particle manipulation, and enhanced droplet control. The platforms can facilitate various analytical challenges such as size-based separations, and delivery of protein crystals for structural discovery with both high selectivity and sensitivity. The vast complexity of biological analytes requires efficient transport and fractionation approaches to understand variations of biomolecular processes and signatures. Size heterogeneity is one characteristic that is especially important to understand for sub-micron organelles such as mitochondria and lipid droplets. It is crucial to resolve populations of sub-cellular or diagnostically relevant bioparticles when these often cannot be resolved with traditional methods. Herein, novel microfluidic tools were developed for the unique migration mechanism capable of separating sub-micron sized bioparticles by size. This based on a deterministic ratchet effect in a symmetrical post array with dielectrophoresis (DEP) for the fast migration allowing separation of polystyrene beads, mitochondria, and liposomes in tens of seconds. This mechanism was further demonstrated using high throughput DEP-based ratchet devices for versatile, continuous sub-micron size particle separation with large sample volumes. Serial femtosecond crystallography (SFX) with X-ray free-electron lasers (XFELs) revolutionized protein structure determination. In SFX experiments, a majority of the continuously injected liquid crystal suspension is wasted due to the unique X-ray pulse structure of XFELs, requiring a large amount (up to grams) of crystal sample to determine a protein structure. To reduce the sample consumption in such experiments, 3D printed droplet-based microfluidic platforms were developed for the generation of aqueous droplets in an oil phase. The implemented droplet-based sample delivery method showed 60% less sample volume consumption compared to the continuous injection at the European XFEL. For the enhanced control of aqueous droplet generation, the device allowed dynamic triggering of droplets for further improvement in synchronization between droplets and the X-ray pulses. This innovative technique of triggering droplets can play a crucial role in saving protein crystals in future SFX experiments. The electric field-assisted unique migration and separation phenomena in microfluidic platforms will be the key solution for revolutionizing the field of organelle separation and structural analysis of proteins.
Dissertation/Thesis
Doctoral Dissertation Chemistry 2020

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Batich, Kristen Anne. "Enhancing Dendritic Cell Migration to Drive Antitumor Responses." Diss., 2017. http://hdl.handle.net/10161/10453.

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The histologic subtypes of malignant glial neoplasms range from anaplastic astrocytoma to the most deadly World Health Organization (WHO) Grade IV glioblastoma (GBM), the most common primary brain tumor in adults. Over the past 40 years, only modest advancements in the treatment of GBM tumors have been reached. Current therapies are predominantly for palliative endpoints rather than curative, although some treatment modalities have been shown to extend survival in particular cases. Patients undergoing current standard of care therapy, including surgical resection, radiation therapy, and chemotherapy, have a median survival of 12-15 months, with less than 25% of patients surviving up to two years and fewer than 10% surviving up to five years. A variety of factors contribute to standard treatment failure, including highly invasive tumor grade at the time of diagnosis, the intrinsic resistance of glioma cells to radiation therapy, the frequent impracticality of maximal tumor resection of eloquent cortical structures, and the fragile intolerance of healthy brain for cytotoxic therapies. Treatment with immunotherapy is a potential answer to the aforementioned problems, as the immune system can be harnessed and educated to license rather potent antitumor responses in a highly specific and safe fashion. One of the most promising vehicles for immunotherapy is the use of dendritic cells, which are professional antigen-presenting cells that are highly effective in the processing of foreign antigens and the education of soon-to-be activated T cells against established tumors. The work outlined in this dissertation encompasses the potential of dendritic cell therapy, the current limitations of reaching full efficacy with this platform, and the recent efforts employed to overcome such barriers. This work spans the characterization and preclinical testing of utilizing protein antigens such as tetanus-diphtheria toxoid to pre-condition the injection site prior to dendritic cell vaccination against established tumors expressing tumor-specific antigens.

Chapter 1 comprises an overview of the current standard therapies for malignant brain tumors. Chapters 2 and 3 provide a review of immunotherapy for malignant gliomas in the setting of preclinical animal models and discuss issues relevant to the efficacy of dendritic cell vaccines for targeting of GBM. Chapters 4 provides the rationale, methodology, and results of research to improve the lymph node homing and immunogenicity of tumor antigen-specific dendritic cell vaccines in mouse models and in patients with newly diagnosed GBM. Chapter 5 delineates the interactions discovered through efforts in Chapter 4 that comprise protein antigen-specific CD4+ T cell responses to induced chemokines and how these interactions result in increased dendritic cell migration and antitumor responses. Lastly, Chapter 6 discusses the future utility of migration of DC vaccines as a surrogate for antitumor responses and clinical outcomes.

This dissertation comprises original research as well as figures and illustrations from previously published material used to exemplify distinct concepts in immunotherapy for cancer. These published examples were reproduced with permission in accordance with journal and publisher policies described in the Appendix.

In summary, this work 1) identifies inefficient lymph node homing of peripherally administered dendritic cells as one of the glaring barriers to effective dendritic cell immunotherapy, 2) provides answers to overcome this limitation with the use of readily available pre-conditioning recall antigens, 3) has opened up a new line of investigation for interaction between recall responses and host chemokines to activate immune responses against a separate antigen, and 4) provides future prospects of utilizing chemokines as adjuvants for additional immunotherapies targeting aggressive tumors. Together, these studies hold great promise to improve the responses in patients with GBM.

Dissertation

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Yang, Tsung-Ming, and 楊宗銘. "Gold migration under high electrical field in Liquid Crystal Display Driver Integrated Circuit." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/53378240183370984116.

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碩士
國立交通大學
工學院碩士在職專班半導體材料與製程設備組
97
As the demand of audio/video entertainment quality rising rapidly, Liquid Crystal Display panel speedily replace the traditional Cathode Ray Tube screens in recent years simultaneously the functional demands of display panel for the color saturation, reaction speed and resolution enhance quickly makes the Inner Lead Bonding pin spacing development on accelerated manner to micro pitch (Fine pitch) through its control of LCD panel pixels and the reaction speed of LCD Driver Integrated Circuit; at the same time the requirement of LCD Driver IC package became more strictly. 　　In the reliability issues, since the Gold migration caused by failure of quality problem cannot be totally avoided at this stage; and cannot be detected on time in the productive detection until the production be used for a period then became failure, it demonstrates the important of reliability. 　　Therefore, the experiment is based on the realistic LCD Driver IC quality failures caused by Gold migration, and for the process to do the necessary observation shows the follow-up prevention

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Chamberland, John. "NECAP2-driven fast recycling controls cell migration and cancer cell invasion." Thesis, 2018. https://hdl.handle.net/2144/32975.

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Abstract:

Vital cellular processes such as nutrient uptake, receptor signaling, and cell migration are controlled by a balance between cell surface receptor internalization and recycling. Clathrin-mediated endocytosis is the major mechanism of receptor internalization in which cargo-enriched endocytic vesicles form at, and are released from, the plasma membrane before maturing into early endosomes. The receptors can then be sorted into fast and slow recycling pathways that replenish receptor levels at the cell surface. A major fast recycling pathway is controlled by the small GTPase Rab4a, which plays a central role in cell migration and cancer cell invasion through regulation of integrin αvβ3 recycling. Recent studies have discovered a family of clathrin-coated vesicle proteins, known as adaptin-ear-binding coat-associated proteins (NECAPs), that consists of two family members, NECAP1 and NECAP2. NECAP1 functions in endocytosis and cooperates with the clathrin adaptor AP-2 to control endocytic vesicle size, number and cargo. Importantly, NECAP2 did not rescue the knock-down phenotype of NECAP1, revealing that NECAPs are not functionally redundant. The studies described in this dissertation show that NECAP2 controls the fast recycling of epidermal growth factor receptor and transferrin receptor. Furthermore, NECAP2 specifically functions in Rab4a-mediated fast recycling together with the clathrin adaptor AP-1. In contrast, NECAP2 has no effect on AP-1-mediated transport from the Golgi or on other Rab4a-dependent sorting events that utilize additional clathrin adaptors and effector proteins. Thus, NECAP2 regulates a sub-route within the Rab4a recycling pathway and, in fact, is the first protein known to date to show this level of specificity. NECAP2 knock-down revealed that this sub-route controls cell migration and cancer cell invasion. Specifically, NECAP2 knock-down impaired the recycling of integrin αvβ3 to the cell surface, leading to decreased Rac1 activation and integrin αvβ3-dependent persistent cell migration. NECAP2 depletion also alleviated the inhibitory effect on integrin α5β1 recycling, switching cells to integrin α5β1-dependent cell migration. Notably, loss of NECAP2 function in breast cancer cells inhibited invasive migration in a 3D invasion model system. Therefore, the NECAP2 pathway may provide a therapeutic target, in particular for the 25% of breast cancers with amplification of Rab4a.

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Dissertations / Theses on the topic 'Drivers of migration'

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