Дисертації з теми "Migration shock"

The research project intends to investigate the responses of households to economic uncertainty and natural shocks and the coping strategies developed both in terms of growing migration rates and remittance inflows and of increasing labour supply. In the first Chapter, we employ household survey data from the Indian State of Kerala to evaluate how transfers of remittances sent from overseas respond to heterogeneous sectoral employment shocks experienced by migrants in the host country during the 2008 crisis. In the second chapter, migration and remittances have been investigated as coping strategies adopted by households after a dramatic flood that hit Bangladesh in August-September 2014. The combination of high-resolution satellite data to precisely measure our treatment variable and the difference-in-difference estimations allow us to causally identify the impact of the dramatic flooding on internal and international migration. The same robust estimation technique is then applied to evaluate the effect of the 2014 flood in Bangladesh on female labour force participation rate and on the probability for unemployed women to enter the labour force. In addition, correcting for selection into employment, we estimate how the flood affects the probability for women working in the household farm to engage in independent wage-earning activities, evaluatiing whether the expected rise in female labour force participation - instrumented by the shock intensity they face - would help to increase their bargaining power within the households.

The research project intends to investigate the responses of households to economic uncertainty and natural shocks and the coping strategies developed both in terms of growing migration rates and remittance inflows and of increasing labour supply. In the first Chapter, we employ household survey data from the Indian State of Kerala to evaluate how transfers of remittances sent from overseas respond to heterogeneous sectoral employment shocks experienced by migrants in the host country during the 2008 crisis. In the second chapter, migration and remittances have been investigated as coping strategies adopted by households after a dramatic flood that hit Bangladesh in August-September 2014. The combination of high-resolution satellite data to precisely measure our treatment variable and the difference-in-difference estimations allow us to causally identify the impact of the dramatic flooding on internal and international migration. The same robust estimation technique is then applied to evaluate the effect of the 2014 flood in Bangladesh on female labour force participation rate and on the probability for unemployed women to enter the labour force. In addition, correcting for selection into employment, we estimate how the flood affects the probability for women working in the household farm to engage in independent wage-earning activities, evaluatiing whether the expected rise in female labour force participation - instrumented by the shock intensity they face - would help to increase their bargaining power within the households.

The ecology of human development has been shown to be different for different cultures and sub-cultures within a particular culture, and to play a significant part in shaping the outcome traits or character profile exhibited by individuals who experience a given ecology. This is the case for members of that sub-culture of children who spend childhood years abroad; who expect to eventually repatriate to their passport country. Those who experience the phenomenon have been called Third Culture Kids or TCKs, and the outcome profile for those with a North American background has been identified. However, no literature on children in the Australasian context exists. A progressive naturalistic study, using both qualitative and quantitative methodology, was undertaken providing foundational data on the experience of adult Australasians (Australians and New Zealanders) who had experienced such a childhood ecology. The Australasian self-reported reflections were compared with descriptions of the North American and international experience presented in existing literature. Further, accepted models of human development were merged and adapted to produce a TCK-specific model of human development. This model was a significant product of this research project. Components of particular importance to development that nurtured the outcome profile traits were identified and represented in the model. The study incorporated three phases: phase 1 involved the in-depth interview of 3 respondents who had experienced the TCK ecology on three different continents, phase 2 involved data collection on the demographics of the broader Australasian TCK population asking questions about family choices, education, and career trajectories (N=50), and phase 3 collected in-depth descriptions of the childhood TCK ecology through voluntary response to an extensive written survey and asked for comparison with the imagined alternative ecology had respondents remained in their passport country (N=45). In both phases 1 and 3 respondents were asked to describe character traits they believed they manifested as a direct result of immersion in the TCK ecology and then suggest traits they might otherwise have manifested had the imagined alternative ecology been the nurturing environment. Tabulation of the emerging data allowed comparison and contrast with the North American outcome profile traits that have been described in literature. In both tabulations many outcome profile traits were identified as being in polar contrast with each other; the TCK could manifest either or both of the apparently opposing traits. Manifestation was dependent upon the immediate context within which the TCK was functioning. There was shown to be a significant overlap in the outcome profile for Australasians and North Americans. However, in this study Australasians presented stronger in their self-report of altered relational patterns and traits related to resourcefulness and practical abilities than was described in the North American literature. In comparing outcome profile traits of the real TCK ecology and those that were associated with the imagined alternative ecology respondents reported that they would have been more confident and more socially competent, but less tolerant and less globally aware had they been raised in the passport country. The self-reported outcome traits or profile were linked to the developmental ecology by exploring the processes and tensions that were at work. It was shown that dynamic tensions emerged and increased in valence as the individual gradually developed polarised traits that manifested according to engagement in the multiple contexts the TCK was required to manage. The results of this study have implications for those who deploy families abroad, as well as those who educate, and nurture the social potential of TCKs. This study has served to extend understanding of the phenomenon at the international level and laid a foundation for specific understanding of the Australasian context.

Hop (the Hsp90/Hsp70 organising protein) is a co-chaperone that acts as an adapter between the major molecular chaperones Hsp90 and Hsp70 during the cellular assembly of the Hsp90 complex. The Hsp90 complex regulates the stability and conformational maturation of a range of important cellular proteins, many of which are deregulated in cancer. In this study, we hypothesised that Hop knockdown inhibits proliferation and migration of cancer cells. We characterised the expression of Hop in cell models of different cancerous status, and provided evidence that Hop was upregulated in tumour cells compared to normal cell counterparts. Using an RNA interference approach, a 60-90% knockdown of Hop was achieved for up to 144 hours in the MDA-MB-231 and Hs578T breast cancer cell lines. Hop knockdown resulted in downregulation of the Hsp90 client proteins, Akt and Stat3, as well as a change in the expression of other Hsp90 co-chaperones, p23, Cdc37 and Aha1, while no change in the levels of Hsp90 or Hsp70 was observed. Silencing of Hop impaired cell proliferation in Hs578T cells but an increase in proliferation in MDA-MB-231, suggesting that the role of Hop in cancer cell proliferation was dependent on type of cancer cell. Hop knockdown in Hs578T and MDA-MB- 231 cells did not lead to any significant changes in the half maximal inhibitory concentrations (IC50) of selected small molecule inhibitors (paclitaxel, geldanamycin and novobiocin) in these cell lines after 72 hours. Hop knockdown cells were however, more sensitive than control cells to the Hsp90 inhibitors geldanamycin and novobiocin at earlier time points and in the presence of the drug transporter inhibitor, verapamil. Hop knockdown caused a decrease in cell migration as measured by the wound healing assay in both Hs578T and MDA-MB-231 cells. Hop was present in purified pseudopodia fractions of migrating cells, and immunofluorescence analysis showed that Hop colocalised with actin at the leading edges of pseudopodia, points of adhesion and at intercellular junctions of cells that have been stimulated to migrate with the chemokine stromal derived factor-1. Hop was able to bind to actin in vitro using actin cosedimentation assays, and silencing of Hop dramatically reduced the capacity of Hs578T cells to form pseudopodia. These results establish a correlation between Hop and actin dynamics, pseudopodia formation and migration in the context of Hop silencing, and collectively suggest that Hop plays a role in cancer cell migration. This study presents experimental evidence for a promising alternative to targeting Hsp90 and Hsp70 chaperones, a novel drug target in cancer therapy.

The ecology of human development has been shown to be different for different cultures and sub-cultures within a particular culture, and to play a significant part in shaping the outcome traits or character profile exhibited by individuals who experience a given ecology. This is the case for members of that sub-culture of children who spend childhood years abroad; who expect to eventually repatriate to their passport country. Those who experience the phenomenon have been called Third Culture Kids or TCKs, and the outcome profile for those with a North American background has been identified. However, no literature on children in the Australasian context exists. A progressive naturalistic study, using both qualitative and quantitative methodology, was undertaken providing foundational data on the experience of adult Australasians (Australians and New Zealanders) who had experienced such a childhood ecology. The Australasian self-reported reflections were compared with descriptions of the North American and international experience presented in existing literature. Further, accepted models of human development were merged and adapted to produce a TCK-specific model of human development. This model was a significant product of this research project. Components of particular importance to development that nurtured the outcome profile traits were identified and represented in the model. The study incorporated three phases: phase 1 involved the in-depth interview of 3 respondents who had experienced the TCK ecology on three different continents, phase 2 involved data collection on the demographics of the broader Australasian TCK population asking questions about family choices, education, and career trajectories (N=50), and phase 3 collected in-depth descriptions of the childhood TCK ecology through voluntary response to an extensive written survey and asked for comparison with the imagined alternative ecology had respondents remained in their passport country (N=45). In both phases 1 and 3 respondents were asked to describe character traits they believed they manifested as a direct result of immersion in the TCK ecology and then suggest traits they might otherwise have manifested had the imagined alternative ecology been the nurturing environment. Tabulation of the emerging data allowed comparison and contrast with the North American outcome profile traits that have been described in literature. In both tabulations many outcome profile traits were identified as being in polar contrast with each other; the TCK could manifest either or both of the apparently opposing traits. Manifestation was dependent upon the immediate context within which the TCK was functioning. There was shown to be a significant overlap in the outcome profile for Australasians and North Americans. However, in this study Australasians presented stronger in their self-report of altered relational patterns and traits related to resourcefulness and practical abilities than was described in the North American literature. In comparing outcome profile traits of the real TCK ecology and those that were associated with the imagined alternative ecology respondents reported that they would have been more confident and more socially competent, but less tolerant and less globally aware had they been raised in the passport country. The self-reported outcome traits or profile were linked to the developmental ecology by exploring the processes and tensions that were at work. It was shown that dynamic tensions emerged and increased in valence as the individual gradually developed polarised traits that manifested according to engagement in the multiple contexts the TCK was required to manage. The results of this study have implications for those who deploy families abroad, as well as those who educate, and nurture the social potential of TCKs. This study has served to extend understanding of the phenomenon at the international level and laid a foundation for specific understanding of the Australasian context.

The ecology of human development has been shown to be different for different cultures and sub-cultures within a particular culture, and to play a significant part in shaping the outcome traits or character profile exhibited by individuals who experience a given ecology. This is the case for members of that sub-culture of children who spend childhood years abroad; who expect to eventually repatriate to their passport country. Those who experience the phenomenon have been called Third Culture Kids or TCKs, and the outcome profile for those with a North American background has been identified. However, no literature on children in the Australasian context exists. A progressive naturalistic study, using both qualitative and quantitative methodology, was undertaken providing foundational data on the experience of adult Australasians (Australians and New Zealanders) who had experienced such a childhood ecology. The Australasian self-reported reflections were compared with descriptions of the North American and international experience presented in existing literature. Further, accepted models of human development were merged and adapted to produce a TCK-specific model of human development. This model was a significant product of this research project. Components of particular importance to development that nurtured the outcome profile traits were identified and represented in the model. The study incorporated three phases: phase 1 involved the in-depth interview of 3 respondents who had experienced the TCK ecology on three different continents, phase 2 involved data collection on the demographics of the broader Australasian TCK population asking questions about family choices, education, and career trajectories (N=50), and phase 3 collected in-depth descriptions of the childhood TCK ecology through voluntary response to an extensive written survey and asked for comparison with the imagined alternative ecology had respondents remained in their passport country (N=45). In both phases 1 and 3 respondents were asked to describe character traits they believed they manifested as a direct result of immersion in the TCK ecology and then suggest traits they might otherwise have manifested had the imagined alternative ecology been the nurturing environment. Tabulation of the emerging data allowed comparison and contrast with the North American outcome profile traits that have been described in literature. In both tabulations many outcome profile traits were identified as being in polar contrast with each other; the TCK could manifest either or both of the apparently opposing traits. Manifestation was dependent upon the immediate context within which the TCK was functioning. There was shown to be a significant overlap in the outcome profile for Australasians and North Americans. However, in this study Australasians presented stronger in their self-report of altered relational patterns and traits related to resourcefulness and practical abilities than was described in the North American literature. In comparing outcome profile traits of the real TCK ecology and those that were associated with the imagined alternative ecology respondents reported that they would have been more confident and more socially competent, but less tolerant and less globally aware had they been raised in the passport country. The self-reported outcome traits or profile were linked to the developmental ecology by exploring the processes and tensions that were at work. It was shown that dynamic tensions emerged and increased in valence as the individual gradually developed polarised traits that manifested according to engagement in the multiple contexts the TCK was required to manage. The results of this study have implications for those who deploy families abroad, as well as those who educate, and nurture the social potential of TCKs. This study has served to extend understanding of the phenomenon at the international level and laid a foundation for specific understanding of the Australasian context.

Current dogma suggests that the Heat Shock Protein (Hsp) molecular chaperones and associated co-chaperones function primarily within the cell, although growing evidence suggests a role for these proteins on the plasma membrane of cancer cells. Hsp90 does not function independently in vivo, but instead functions with a variety of partner chaperones and co-chaperones, that include Hsp70 and Hsp90/Hsp70 organising protein (Hop), which are thought to regulate ATP hydrolysis and the binding of Hsp90 to its client proteins. Hsp90 on the plasma membrane appears to have distinct roles in pathways leading to cell motility, invasion and metastasis. We hypothesised that Hsp90 on the plasma membrane is present as part of a multi-chaperone complex that participates in the chaperone-assisted folding of client membrane proteins in a manner analogous to the intracellular chaperone complex. This study characterised the membrane expression of Hsp90, Hsp70 and Hop in different cell models of different adhesive and migratory capacity, namely MDA-MB-231 (metastatic adherent breast cancer cell line), MCF-7 (non-metastatic adherent breast cancer cell line), U937 and THP1 (monocytic leukemia suspension cell lines). Membrane expression of the Hsps was analysed using a combination of subcellular fractionation, biotin-streptavidin affinity purification and immunofluorescence. This study provided evidence to suggest that Hsp90, Hsp70 and Hop are membrane associated in MDA-MB-231 and MCF-7 breast cancer cells. Hsp90, Hsp70 and Hop associated with the plasma membrane such that at least part of the protein is located extracellularly. Immunofluorescence analysis showed that Hsp90, Hsp70 and Hop at the leading edge may localize to membrane ruffles in MDA-MB-231 cells, in accordance with the published role of Hsp90 in migration. An increase in this response was seen in cells stimulated to migrate with SDF-1. By immunoprecipitation, we isolated a putative extracellular membrane associated complex containing Hsp90, Hsp70 and Hop. Using soluble Hsp90 and antibodies against membrane associated Hsp90, we suggested roles for soluble extracellular Hsp90 in mediating migration by wound healing assays and inducing actin reorganisation and vinculin-based focal adhesion formation. The effects of extracellular Hsp90 are mediated by signalling through an ERK1/2 dependent pathway. An anti-Hsp90 antibody against an N-terminal epitope in Hsp90 appeared to be able to overcome the death inducing effects of a combination of SDF-1 and AMD3100, while soluble Hsp90 could not overcome this effect. We propose that this study provides preliminary evidence that extracellular Hsp90 functions as part of a multi-chaperone complex that includes Hsp70 and Hop. The extracellular Hsp90 chaperone complex may mediate cell processes such as migration by modulating the conformation of cell surface receptors, leading to downstream signalling.

The following is a study of the impact of migration on unemployment rates for natives in Sweden, on municipal level. A cross sectional data set has been analyzed using multiple linear regressions. The regression analysis has searched for the impact on the unemployment rates among natives of the size of the share of migrants in the municipalities as well as of the change in the size of the share of migrants during a time span of 13 years. The results show that migration has small or non-existent impact on the unemployment rates of natives. The results vary depending on the period being investigated and also depending on the characteristics of the municipality that is investigated. When dividing the municipalities into three categories (city, urban and rural municipalities) significant impact of migration on native’s unemployment rates is to be found in city and urban municipalities, but not in rural. The results also indicate that the most significant impact is to be found in the present period of time, while in the long term the impact diminishes to become less significant or not significant at all. 10% migrants in a city municipality in 2015 increased natives’ unemployment level that same year by 0.4 percentage units. More rapid increases of the share of migrants in the labor force have more impact as well. A municipality were the share of migrants grew with 1 percentage unit between 2003 and 2015, had 0.1 percentage unit higher unemployment rate for natives in 2015. This study’s results follow the pattern from earlier studies in the field, that since the 1990’s have shown similar effects when measuring different countries on different continents – sometimes the effect has been significant, sometimes not, and when significant the impact has been rather small, often clustering around zero.

Les recherches exposées dans ce document portent sur l'étude du rôle de HSF2 au cours du développement du système nerveux central. Les Heat Shock Factors (HSF) sont impliqués dans la réponse au choc thermique et également au cours du développement embryonnaire. Mes travaux ont démontré que HSF2 est requis au cours de la formation du cortex cérébral pour la migration de certains neurones en régulant directement l'expression de p35, sous unité activatrice de CDK5. D'autres cibles ont été identifiées NudE, Dclk, Dab1 nécessaires à la migration des neurones en participant à la dynamique du cytosquelette. De plus, ces travaux montrent que HSF2 module la prolifération et la différenciation des cellules souches neurales (NSC) et des progéniteurs (NP) car i) par électroporation in ovo chez le poulet, la surexpression de HSF2 provoque une augmentation de la prolifération des NP; ii) les NSC Hsf2−/− en culture présentent un retard de prolifération, de survie et de différenciation. Ainsi, HSF2 pourrait assister la décision cellulaire des NSC/NP vers la prolifération ou la différenciation et la migration, tel un aiguilleur de destin cellulaire

With the recent influx of foreign-born individuals migrating to Sweden, this study aims to answer the question, “do high skilled foreign-born individuals relate positively to average wages in Sweden?”. We specifically observe high skilled foreign-born individuals and their contribution to the average wage across different municipalities in Sweden between the years 2011 and 2018. The method carried out in this study consisted of an empirical analysis where the significance of economic factors was interpreted in order to understand the variation in wages. The data was extracted from Statistics Sweden. The relationship of the share of highly educated foreign-born individuals has proved to be insignificant with respect to average wages in Sweden. Different theories are discussed in this paper in order to identify the key labour market outcomes due to the labour supply shock. Our findings disclose that differences in wages are present, meaning that natives and foreign-born individuals are complements in the short run

This thesis examines the representation of temporary migrants in the OCVID-19 pandemic in New Zealand. The aim of the study is to understand how the pandemic effected this early decision making by the New Zealand Parliament in correlation with migration, more specific, the temporary migrants who are stuck within New Zealands borders. These issues can be linked with shock mobility, more specific, with immobility within shock. The material is analysed with the WPR method. The study concludes that there is a changing discourse and a changing representation of the temporary migrants. Where at first the New Zealand citizens have to be protected, later on in the discourse the migrants need to be helped and it is followed by financial gain that the temporary migrants bring with their labour and spending. The findings create a contribution in the field of shock mobility, with a focus on the immobility within shock mobility.

Thesis (PhD) - Faculty of Higher Education, Lilydale, Swinburne University of Technology, 2009.
Thesis submitted in fulfilment of the requirements for the degree Doctor of Philosophy, Faculty of Higher Education, Lilydale, Swinburne University of Technology - 2009. Typescript. Includes bibliographical references (p. ??-??)

Epithelial cells are necessary building blocks of the organs they line. Their apicalbasolateral polarity, characterized by an asymmetric distribution of cell components along their apical-basal axis, is a requirement for normal organ function. Although the centrosome, also known as the microtubule organizing center, is important in establishing cell polarity the mechanisms through which it achieves this remain unclear. It has been suggested that the centrosome influences cell polarity through microtubule cytoskeleton organization and endosome trafficking. In the first chapter of this thesis, I summarize the current understanding of the mechanisms regulating cell polarity and review evidence for the role of centrosomes in this process. In the second chapter, I examine the roles of the mother centriole appendages in cell polarity during cell migration and cell division. Interestingly, the subdistal appendages, but not the distal appendages, are essential in both processes, a role they achieve through organizing centrosomal microtubules. Depletion of subdistal appendages disrupts microtubule organization at the centrosome and hence, affects microtubule stability. These microtubule defects affect centrosome reorientation and spindle orientation during cell migration and division, respectively. In addition, depletion of subdistal appendages affects the localization and dynamics of apical polarity proteins in relation to microtubule stability and endosome recycling. Taken together, our results suggest the mother centriole subdistal appendages play an essential role in regulating cell polarity. A discussion of the significance of these results is included in chapter three.

Epithelial cells are necessary building blocks of the organs they line. Their apicalbasolateral polarity, characterized by an asymmetric distribution of cell components along their apical-basal axis, is a requirement for normal organ function. Although the centrosome, also known as the microtubule organizing center, is important in establishing cell polarity the mechanisms through which it achieves this remain unclear. It has been suggested that the centrosome influences cell polarity through microtubule cytoskeleton organization and endosome trafficking. In the first chapter of this thesis, I summarize the current understanding of the mechanisms regulating cell polarity and review evidence for the role of centrosomes in this process. In the second chapter, I examine the roles of the mother centriole appendages in cell polarity during cell migration and cell division. Interestingly, the subdistal appendages, but not the distal appendages, are essential in both processes, a role they achieve through organizing centrosomal microtubules. Depletion of subdistal appendages disrupts microtubule organization at the centrosome and hence, affects microtubule stability. These microtubule defects affect centrosome reorientation and spindle orientation during cell migration and division, respectively. In addition, depletion of subdistal appendages affects the localization and dynamics of apical polarity proteins in relation to microtubule stability and endosome recycling. Taken together, our results suggest the mother centriole subdistal appendages play an essential role in regulating cell polarity. A discussion of the significance of these results is included in chapter three.

This dissertation consists of four self-contained essays on the economic geography of oppressive violent deviant behaviours, a definition identifying violent violations of social norms driven by oppressive urges against minorities. The common thread running through the essays is the quantitative exploration of how the local socioeconomic characteristics influence the occurrence and the scale of violence directed towards disempowered groups. The first chapter investigates the relationship between hate events and the socioeconomic/cultural characteristics of Italian Local Labour Market Areas, through a unique database with georeferenced hate manifestations. The estimation of a hurdle model identifies the local conditions acting as risk factors for hate occurrence and for hate frequency. The geography of refugees’ hosting structures appears as a predictor of both the occurrence and the frequency of hate, whereas foreign resident population does not display any significant influence. At the same time, trust works as a protective factor reducing the occurrence of hatred at the local level. Moreover, once the hurdle of experiencing at least one hate manifestation is crossed, fewer conditions are needed to fuel further hate in the same place. The second chapter analyses the influence of real-world socioeconomic features on online hate in Italy, exploiting a novel dataset on geotagged hate tweets. Results show a strong empirical association between the local economic dimension and cyberhate. Economic insecurity is robust risk factors for online hate, as well as economic inequality. The latter influences online hate along two channels: the local outlook of income inequality and the relative importance assigned to individualistic values by the established family type in the area. In the third chapter I investigate whether school bullying is affected by a cultural shock from migration. The analysis exploits the natural shock from migration which occurred in the UK after the 2004 European Union enlargement to empirically estimate how a sudden and sizeable migration inflow influences school bullying. The findings -robust to endogeneity of immigrants’ location choice- highlight that the cultural shock from migration determines an increase in school violence. The paper also suggests that existing language barriers act as a moderator for the migration shock by increasing its effect. The final chapter explores whether women’ propensity to report sexual crimes to the police is influenced by the local availability of specialized services for victims of sexual offences. Applying the synthetic control method to the UK, the empirical investigation shows that the local availability of dedicated services, as refuges and professional help, increases women’s willingness to seek justice. The positive effect of the local provision of specialized services holds even after the occurrence a of countrywide and prominent media campaign about sexual offences. This last finding further supports the importance of the availability of nearby services, since it suggests that nation-scale initiatives do not work as substitutes.

Cette thèse contribue à la littérature sur l'impact des chocs climatiques sur les migrations et la sécurité alimentaire. Le premier chapitre examine les migrations induites par les chocs climatiques en Tanzanie en employant l'approche de iv provbit. Les résultats suggèrent que pour un ménage moyen, une réduction d'un pour cent du revenu agricole induite par le choc climatique augmente la probabilité de migration de 13 points de pourcentage en moyenne au cours de l'année suivante. Le deuxième chapitre tente d'établir si le climat est un déterminant du choix de la destination en cas de migration rurale-rurale. En utilisant le modèle du logit conditionnel, ce chapitre montre qu'une augmentation d'écarts de revenus entre destination et origine de I 0000 shillings tanzaniens, attribuable au climat, augmente la probabilité du choix de cette destination de 2 points de pourcentage. Le troisième chapitre s'intéresse au lien entre les chocs climatiques et la sécurité alimentaire. En utilisant les données sud-africaines, cette analyse emploie un modèle de variable instrumentale où la diversité alimentaire, une mesure de l'accès à la nourriture, est déterminée par les prix des aliments instrumentés avec un choc climatique. Les résultats suggèrent qu'une augmentation de pourcent des prix alimentaires locaux induite par un choc climatique diminue la diversité alimentaire de 2,5 pourcent
This thesis contributes to the literature on the impact of weather shocks on migration and food security in Sub-Saharan Africa. The first chapter analyses whether Tanzanian rural households engage in internal migration as a response to weather-related shocks using an iv probit model. The findings confirm that for an average household, a 1 per cent reduction in agricultural income induced by weather shock increases the probability of migration by 13 percentage points on average within the following year. The second chapter paper attempts to establish if weather acts as the determinant of destination choice in the case of rural-to-rural migration. Employing the alternative-specific conditional logit model, this paper shows that an increase in the expected income differentials between origin and destination by 10,000 Tanzanian shillings, attributable to differences in weather, increases the probability of choosing a given destination by 2 percentage points. The third chapter analyses the food access dimension of food security, and models the link between weather shocks and food security that acts specifically through food prices. Employing an instrumental variable model where household dietary diversity is determined by food prices instrumented with weather shock, this chapter shows that a 1 per cent increase in local food prices induced by a weather shock decreases the number of food items consumed by households by around 2.5 per cent

Cette thèse aborde différentes thématiques dans le champ de l’économie internationale et de la macroéconomie. Les travaux de recherche développés dans cette thèse étudient l’impact des chocs de différentes natures sur les flux de migrations internationales, de commerce international et sur la croissance de la productivité. Le premier chapitre s’intéresse à l’évolution des flux migratoires en réaction à des chocs conjoncturels. L’estimation du modèle à partir des données nous permet de conclure qu’à la fois les chocs structurels et les chocs conjoncturels influent les flux de migration. Une augmentation de 10% du salaire du pays de destination conduirait à une augmentation du flux migratoire vers ce pays de destination de près de 8%, toutes choses égales par ailleurs. Le second chapitre étudie dans quelles mesures les chocs financiers affectent le niveau des exportations des entreprises, avec un focus particulier sur les entreprises qui exportent vers des destinations lointaines. Nous trouvons que les entreprises qui font face à des frictions financières exportent entre 4% et 10% de moins que celles qui ne sont pas soumises à ces frictions. Nos résultats montrent également que parmi les exportateurs en difficulté financière, ceux qui exportent vers des destinations lointaines réduisent encore davantage leurs exportations. Dans le chapitre trois, nous étudions comment les frictions financières peuvent conduire à des distorsions dans l’allocation des ressources. Nos résultats suggèrent que dans les pays développés financièrement, les capitaux ne permettent pas forcément une amélioration de l’allocation efficace du travail entre les firmes
This thesis covers various issues in international economics and macroeconomics.It studies the role of several types of shocks on international migration, firms’ export strategies and sectoral productivity growth. The three chapters exploit different sources of data and use recent econometrics approaches to deal with these issues.Chapter one contributes to the literature on international migration by looking at the role of short-run fluctuations as determinants of the location choice of the migrants. We find evidence that business cycles and employment rates at destination affect the intensity of gross bilateral flows.Chapter two investigates how financial frictions impact firms’ foreign sales, especially for firms that export to long distance export markets. We find that firmsfacing financial frictions export from 4 to 10% less than the ones without anyfinancial constraints. Our results also suggest that amongst exporters facing financial difficulties, those who export to faraway destinations reduce their exportsales more.Chapter three investigates how financial frictions affect the efficiency with which labor allocates across firms within a sector. Results suggest that an increase intangibility decreases the productivity growth rate of an industry located in highly financially developed country and this lower productivity growth rate is largely explained by the reallocation of labour across firms within the sector

Cette thèse porte sur l'impact des chocs de revenu sur les migrations des individus. Le chapitre 2 utilise des estimations à effets fixes et des variables instrumentales pour mesurer l'impact de chocs sur le revenu de l'exploitation agricole sur des migrations temporaires de ménages ruraux en Inde. Le chapitre 3 examine la migration sur la période allant de 1993 à 2000 pour comprendre les décisions de migration avant et après la crise financière indonésienne de 1997/1998. Dans le chapitre 5, nous examinons l'impact de chocs de revenu en 2004 ou 2005 déclarés par les ménages sur la migration en 2005 ou 2006 et sur les transferts en 2006. La migration temporaire dans les ménages ruraux en Inde et la migration permanente au Sénégal semblent être des moyens de gestion des chocs mais dans un modèle classique de migration de travail, avec une augmentation des départs en réponse à des chocs négatifs. En Inde, un petit impact positif des chocs positifs idiosyncratiques laisse à penser que les migrations sont peut-être quelque peu limitées par des contraintes de liquidité. Toutefois, ces dernières semblent très faibles au regard du choc agrégé de faible pluie qui, lui, augmente les migrations. Au Sénégal, nous trouvons également des éléments allant dans le sens d'une conception plus large de la migration comme outil de gestion des chocs, avec des dépendants rejoignant des ménages ayant connu des chocs positifs. En Indonésie toutefois, nous ne trouvons pas que la migration a augmenté pour les individus affectés par la crise. Le caractère généralisé du choc, bien qu'hétérogène, a pu figer les situations et rendre les individus moins enclins à prendre des risques en migrant
This dissertation examines the impact of income shocks on migration. Chapter 2 uses fixed-effect and instrumental variable estimates to measure the impact of farm income shocks on temporary migration of rural households in India. Chapter 3 examines migration throughout the period spanning 1993-2000 to understand migration decisions before and after the Indonesian 1997/1998 financial crisis. In chapter 4, I examine the impact of income shocks in 2004 or 2005 as mentioned by the interviewed households on migration m 2005 or 2006 and on transfers in 2006. Temporary migration in rural households in India and permanent migration in Senegal seem to be coping mechanisms in a classic model of labor migration, with an increase in departures in reponse to negative shocks. In India, a small positive impact of positive idiosyncratic shocks hints towards response to negative shocks. In India, a small positive impact of positive idiosyncratic shocks hints towards possible limitation of migration due to liquidity constraints. However, these constraints seem very weak when compared with the impact of the aggregate shock of low rainfall which increases migration. In Senegal, we also find some hints towards a larger understanding of migration as a means to manage shocks, with dependents joining households who have experiences positive shocks. In Indonesia however, we do not find that migration has increased in the case of individuals particularly affected by the crisis. The pervasive nature of the shock, even though it was heterogeneous, may have made individuals less willing to take risks through migration

This study responds to the need for more research around (im)mobility decision-making to better support people facing environmental shocks and climatic changes. The concept of Trapped Populations, first appeared with the release of the 2011 Foresight report yielding repeated use in environmental migration studies and to a more limited extent policy. Although a seemingly straightforward concept, referring to people's inability to move away from environmental high-risk areas despite a desire to do so, the underlying reasons for someone's immobility can be profoundly complex. The empirical literature body referring to ‘trapped' populations has similarly taken a fairly simple and narrow economic explanatory approach. A more comprehensive understanding around how immobility is narrated in academia, and how people's cultural, social and psychological background in Bangladesh influences their (im)mobility, can provide crucial research insights. To better protect and support people living with environmental shocks and changes worldwide we need to build robust and well-informed policy frameworks To achieve this, a set of discourse analyses were carried out. Firstly, a textual Critical Discourse Analysis (CDA) reviewed how ‘trapped' has been framed within academia. Secondly, a Foucauldian inspired discourse analysis was performed on field data to explore how power, knowledge and and binary opposites shape and determine people's social norms in terms of their (im)mobility decision-making. These key concepts critically showcased how meaning, values and power can constrain the mobility of a social group. The analysis was carried out on a large set of field data gathered between 2014 and 2016 in Bangladesh. The data on urban immobility and rural non-evacuation behaviour was gathered through a mixed-method quant-qualitative approach that included Q-methodology, storytelling group sessions, in-depth interviews and a survey questionnaire. Other key concepts used to frame the analysis included those of subjectivity, gender, place and space. The textual discourse analysis highlighted the dangers of framing mobility or resettlement as a potential climate adaptation. Assisted migration, could for example end up disguising other hidden political and economic agendas. The research identified how the empirical notions of ‘trapped' move beyond economic immobility. People in Bangladesh described being socially, psychologically and emotionally ‘trapped'. These empirical notions are useful within the area of climate policy, as they raise questions around whether mobility in fact is the solution.

Public opinion tends to look at Zambia as some mythical land of promise, predestined to enjoy for years to come the same sort of economic bliss as during the copper price boom of 1964 -75. But there can be little doubt that one of the most striking facts of Zambia's economic history since 1964 has been poor macroeconomic performance. Since the mid 1970's Zambia's economy has experienced negative economic growth, high unemployment, rapid inflation and a weak balance of payments. This problem is crucial in the context of two-gap models. This thesis discusses the main facts about this worrying development and advances a line of argument which may well account for most of the observed facts. Prior to the Third Republic Zambian politicians tended to blame external forces for the current problems. My main contention is that that is wrong Economic difficulties arose from a combination of policy failures: growth of 'nonmarketable output', the government's politically induced tendency for crisis management, coupled with its well known propensity to delay taking corrective action, against a background of difficult initial conditions. However, since this is a thesis, both the scope and the method of investigation are limited by the time allowed for the study. What we do is to use historical data and use econometric analysis to shape my arguments, and to make them plausible. Inadequate domestic savings reflected in investment slumps, coupled with foreign exchange shortages, are shown to be the ultimate constraint on economic growth performance. The new government's liberal attitude and the fact that there is export potential in the economy offers some hope for success but the thesis draws attention to the structural rigidities which will remain a major constraint to export diversification in the short to medium term. In the long run, non-traditional exports would have to grow by some 30 percent annually if they were to become the new engine of growth. We stress that success will depend crucially on the government's macroeconomic policies being both conducive to the promotion of investment spending and supportive to the objective of restoring viability in the balance of payments.

Given the importance of agricultural income for rural households, erratic weather conditions pose an austere threat to these households' livelihoods. This thesis explores ways through which households in agrarian economies smooth their consumption, engage in community networks, and readjust their labour allocation in response to shocks. In a setting of inherent risk, absence of institutional insurance, and labour market inefficiencies, poor households are often left to their own devices to cope with risk. The aim of this study is to examine the different risk-coping strategies adopted by households in rural India, assess their effectiveness, and derive implications for public policy. The results suggest that, in an environment characterised by agro-climatic risk, households are able to self-insure and smooth their consumption in the face of income shocks. Their coping mechanisms, however, may reduce their resilience to future shocks. In fact, small landholders tend to rely more heavily on their productive asset stock, while medium landholders find it optimal to preserve and accumulate their productive assets when exposed to exogenous income shocks. Households also change their labour allocation and reduce their self-employment in agriculture. Furthermore, households in rural areas can migrate to urban areas or engage in societal risk-sharing arrangements to mitigate the risk. The results of this thesis suggest that being part of a community network discourages individuals' migration and increases the likelihood of undertaking riskier activities. The findings also confirm the importance of portfolio adjustments and the diversification of household assets in buffering consumption. These conclusions form the basis of several policy implications, the most important of which is providing formal insurance schemes to encourage the accumulation of assets, technology, and skills.

There is near unanimous agreement in the scientific community that global mean temperatures will increase by several degrees Celsius by the end of the century. This could lead to dramatic consequences, especially for the poor in the developing world. In many countries climate change will manifest itself through reduced rainfall, greater temperature variability, a rise in sea levels, and a higher frequency of weather shocks. These effects constitute threats to people’s ability to continue to live where they are living today, and more generally to their economic security, and may lead to higher levels of migration away from areas vulnerable to climate change.While environmental change may lead to an increase in migration, in most cases it may not be feasible to identify pure environmental migrants because of the complexity of the push and pull factors involved. The aim of this dissertation is to assess the extent to which households are vulnerable today to environmental change and weather shocks in selected areas of the Middle East and North Africa (MENA) region and in South Asia’s Sundarbans, whether households are able to cope with weather shocks and adapt to changing environmental conditions, and whether climatic conditions and weather shocks are leading to higher rates of migration. The dissertation relies in large part on the analysis of new households surveys recently implemented in areas affected by weather shocks and changing climatic conditions in seven countries: Algeria, Bangladesh, Egypt, India, Morocco, Syria, and Yemen. While the MENA countries are affected mostly by droughts, and to a lower extent floods, the Sundarbans in Bangladesh and India are affected by cyclones, sea water surges, and salinity intrusions. The ways in which households are affected by extreme weather events are very different in the MENA and South Asia regions. Yet as the dissertation demonstrates, while circumstances and contexts differ between the two sets of countries, many of the findings are actually similar in both regions. The first part of the dissertation provides background for the empirical work. After a review of the literature, a set of 10 questions are asked together with hypotheses to be tested. The second part of the dissertation provides the empirical results, with three chapters focusing on (1) household perceptions about their environment and the impact of weather shocks on households; (2) the coping mechanisms and adaptation strategies deployed by households; and (3) migration decisions, in most cases by individual household members. The findings from the dissertation suggest that individuals from households more seriously and negatively affected by weather shocks and changes in their environment are slightly more likely to migrate temporarily, but not permanently. This is possibly due to the cost of migration and the fact that environmental change and weather shocks may result in large losses in income and assets for vulnerable groups, making migration less affordable for them. Thus, some population groups may well be in a situation of "relative trappedness" in comparison to other households less affected by weather shocks and changes in their environment._____________La communauté scientifique est quasi unanime sur le fait que les températures mondiales moyennes devraient augmenter de plusieurs degrés Celsius d'ici la fin du siècle. Cela pourrait avoir des conséquences dramatiques pour les populations, en particulier pour les pauvres dans les pays en voie de développement. Dans de nombreux pays le changement climatique va se manifester par une diminution des précipitations, une plus grande variabilité de la température, une élévation du niveau de la mer, et une fréquence plus élevée des chocs climatiques. Ces effets constituent des menaces pour la capacité des populations de continuer à vivre là où elles vivent aujourd'hui, ce qui pourrait par conséquent entraîner des mouvements migratoires importants.Cependant, même si les chocs climatiques pourraient mener à une augmentation de la migration, dans la plupart des cas il n’est pas possible d'identifier des migrants environnementaux dits purs en raison de la complexité des facteurs influençant la migration. Dans ce contexte, l'objectif de la thèse est triple. La thèse cherche à évaluer (1) dans quelle mesure les ménages sont vulnérables aujourd'hui aux changements environnementaux et aux chocs climatiques dans certaines régions de l'Afrique du Nord, du Moyen-Orient, et de l’Asie du Sud (Sundarbans) ;(2) si les ménages sont en mesure de faire face aux chocs climatiques, et (3) si les conditions environnementales et les chocs climatiques conduisent à des taux de migration plus élevés parmi les membres des ménages les plus affectés comparativement aux ménages moins affectés. La thèse repose en partie sur une analyse de nouvelles données d’enquêtes auprès des ménages mises en œuvre dans des zones touchées par les chocs climatiques dans sept pays :l’Algérie, le Bangladesh, l’Egypte, l’Inde, le Maroc, la Syrie et le Yémen. Alors que les pays du Moyen Orient et d’Afrique du Nord sont touchés principalement par des sécheresses, et dans une moindre mesure par des inondations, la zone géographique dite des Sundarbans au Bangladesh et en Inde est touchée principalement par des cyclones.Bien que les chocs climatiques dans les deux régions soient différents, la thèse montre que les implications pour les ménages sont similaires. Les groupes vulnérables sont fortement et négativement affectés par les chocs climatiques et ils ne sont souvent pas capables de faire face et de s’adapter efficacement à ces chocs. De plus, il semble que les ménages les plus affectés n’aient pas de taux de migration permanente parmi leurs membres plus élevés que les ménages moins affectés, même si les taux de migration temporaire sont légèrement plus élevés. En ce sens, il apparait que les groupes vulnérables pourraient être en termes comparatifs pris au piège (« relative trappedness ») dans les zones vulnérables aux chocs climatiques comme d’autres études l’ont suggéré.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

Learning plays an important role in adopting new technology. While the role of learning in the decision to adopt is widely investigated in the literature, its role in knowing how to best use technology and the speed of learning is not. For instance, when farmers adopt groundwater extraction technology, they need to learn their private marginal cost and marginal benefit of extracting water. Comparing the extraction behavior of the owners of new wells with old wells, we explore the role of experience in shaping farmers' decisions. We use three identification strategies to test the hypothesis that owners of new wells extract more water than owners of old wells. Employing panel data at the district level in a fixed-effects model, we find that groundwater extraction rises as the growth rate in new wells increases. Our second strategy uses the exogenous variation in precipitation shocks in a double-difference approach. Employing census data at the well level, we show that more water is extracted from new wells than older wells and that the difference in extraction increases in areas that experience negative precipitation shocks. The third strategy is the nearest-neighbor matching method which confirms the above findings and indicates that old wells are more efficient in maintaining their inter-temporal extraction. We also provide evidence regarding the speed of learning about using technology. Our findings have important implications for discussions of common pool regulation. Firms are often considered entities with complete private information about their true abatement costs. Our findings imply that quantity instruments for regulating groundwater extraction fail to guarantee productive efficiency when farmers face uncertainty about their marginal abatement cost. This paper also provides new insights for optimizing climate change scenarios, in light of the importance of the learning lag in using new technologies. In chapter two, we discuss the effects of precipitation shocks on the rural labor market and migration. The welfare of both agrarian and non-agrarian workers in rural areas is highly affected by agricultural output volatility, caused in part by weather shocks. This paper examines the impact of precipitation shocks on labor supply and out-migration in rural Iran. We use individual-level panel data combined with station-based precipitation data at the rural-agglomeration level to study the intensive and extensive margins of employment. Our results indicate different types of responses to positive and negative shocks. Using a fixed-effects panel data model, we find that workers in agriculture and industry sectors increase their hours of work in response to positive shocks. At the extensive margin, we find that negative shocks reduce the labor market participation of women. We observed heterogeneity in responses based on the sector of employment, gender, and the roles of individuals in the household. We also show that positive shocks affect the division of labor at the household level. Our estimates for the probability of migration indicate that negative shocks raise the probability of migration for young men. We show that the labor-migration of the same group is also affected by negative shocks, but the impact could be explained by the local unemployment rate, implying the labor market is a channel through which precipitation shocks affect migratory decisions. In the final chapter, we investigate parents' investment in the quality of their children. While school enrollment at the primary level has been rising in developing countries to almost complete national coverage, international measures of education quality, especially in basic knowledge of reading and math, do not exhibit a parallel improvement. Since parents' expenditure is an important determinant of children's school performance, we investigate parents' investments in the quality of their children's education, measured by their spending on books and other school materials. We develop an overlapping generations model, in which we consider families' expenditure as an input to their children's human capital. Moreover, in our model, parents use the current status of their children's human capital as a screening measure for adjusting their investment, instead of the standard tradition of simply balancing the trade-off between future income and the current stream of direct and indirect school costs. From our theoretical analysis, our main hypothesis is that families consider better school performance to be a reliable predictor of future return, and this incentivizes them to invest more in children who are academically promising, considering other determinants of children's schooling output, such as school quality. Empirically, we use an instrumental variables approach to test our main hypothesis, and it is accepted using data for Ghanaian primary school students in rural areas.
Doctor of Philosophy
Adopting new technology need learning, either in the form of knowledge or by working with the adopted technology. While the role of learning in the decision to adopt is widely investigated in the literature, its role in knowing how to best use technology and the speed of learning is not. In the first chapter, we investigate the adoption of the use of groundwater technology. When farmers adopt groundwater extraction technology, they need to learn about how to best use the technology to maximize their profit in the short and long run. We use five sets of data from Iran to show the existence of learning in the use of groundwater technology. Our findings improve the discussion on the regulation of firms in using common resources. This paper also provides new insights for optimizing climate change scenarios, in light of the importance of the learning lag in using new technologies. In chapter two, we discuss the effects of precipitation shocks on the rural labor market and migration. Weather shocks affect the welfare of workers in rural areas. This paper examines the impact of precipitation shocks on labor supply and out-migration in rural Iran. We use individual-level and station-based precipitation data at the rural-agglomeration level to study the effects of precipitation shocks on employment. Our results indicate different types of responses to positive and negative shocks. We find that workers in agriculture and industry sectors increase their hours of work in response to positive shocks and negative shocks reduce the labor market participation of women. We also show that the labor market is a channel through which precipitation shocks affect migratory decisions. In the final chapter, we investigate parents' investment in the quality of their children. While school enrollment at the primary level has been rising in developing countries, international measures of education quality, especially in basic knowledge of reading and math, do not exhibit a parallel improvement. Since parents' expenditure is an important determinant of children's school performance, we investigate parents' investments in the quality of their children's education, measured by their spending on books and other school materials. We develop a model, in which we consider families' expenditure as an input to their children's human capital. We hypothesize that families consider better school performance to be a reliable predictor of future return. Empirically, we test our hypothesis, and it is accepted using data for Ghanaian primary school students in rural areas.

The purpose of this project was to develop a website to relieve Korean returnees' reverse culture shock and help their re-adaptation process. A website can be an outstanding resource for returnees in terms of accessibility because the target audiences are scattered all over the world.

Les trois essais composant cette thèse apportent des contributions à la littérature sur les conséquences de la migration et des transferts privés sur le développement économique des pays d'origine d'Afrique Subsaharienne.Le premier essai évalue l'impact distributif des transferts internationaux et domestiques au Sénégal. Les résultats montrent que les transferts privés réduisent l'inégalité de revenu au Sénégal. Cet effet égalisateur semble principalement tiré par les transferts domestiques. Le deuxième essai examine la fonction d'assurance de la migration au Mali. Nous trouvons que la migration agit comme un mécanisme d'assurance lorsque le ménage est victime d'un choc idiosyncratique au cours de l'année. Le troisième essai étudie le lien entre le capital humain des migrants sénégalais et leur insertion sur le marché de travail de destination. Les résultats suggèrent que la probabilité d'être en emploi qualifié étant donné le niveau d'éducation est inférieure en migration par rapport au Sénégal.Bien qu'à priori distincts, ces trois essais ont en commun une approche qui mobilise des enquêtes ménages ainsi que des techniques micro-économétriques diverses au regard du caractère complexe de la migration afin d'apporter des éclairages sur les conséquences de la migration sur les économies d'origine
The three essays composing this thesis make contributions to the literature on the consequences of migration and private transfers on the economic development of the countries of origin of sub-Saharan Africa.The first essay evaluates the distributive impact of international and domestic transfersin Senegal. The results show that private transfers reduce income inequality in Senegal. This equalizing effect is mainly driven bydomestic transfers. The second essay examines the insurance function of migration in Mali. We find that migration acts as an insurance mechanism when the household suffers an idiosyncratic shock during the year. The third essay examines the link between the human capital of Senegalese migrants and their integration into the destination labor market. The results suggest that the probability of being in skilled employment given the level of education is lower in migration compared to Senegal. Although a priori distinct, the three essays have in common an approach that mobilizes household surveys and various microeconometric techniques to deal with the complexity of migration in order to improve the understanding of the consequences of migration on the economies of origines

This thesis consists of five papers, which concern expenditure decisions and economic growth within Swedish local government.Paper [1] explores the hypothesis that local fiscal shocks have short run effects on revenue and expenditure decisions made within local government. It is found that although fiscal shocks do not affect local authorities' revenue decisions, they do induce municipalities to change expenditures and financial costs along with short term loans. Local authorities are also found to respond more powerful to unfavorable fiscal shocks (deficit shocks) than to favorable fiscal shocks (surplus shocks).In Paper [2], we study the hypothesis that local (municipal) expenditures, in part, can be explained by regional (county) expenditures. We formulate and estimate a demand model for municipal services that is defined conditional on the county expenditures. The results imply a positive dependency between the provision of county and municipal services. Moreover, the results suggest that the hypothesis of weak separability between the provision of county and municipal services can be rejected. In addition, we cannot reject the hypothesis that the regional expenditures are weakly exogenous in the local expenditure equation.In Paper [3] the existence of spillover between Swedish municipalities in the provision of recreational and cultural services is analyzed. A representative .voter model is derived and the demand for recreational and cultural services is estimated using spatial SUR techniques. The results suggest a negative relationship between recreational and cultural expenditures provided by neighboring municipalities, which indicates that these services are substitutes.Paper [4] concerns the regional growth pattern in Sweden by analyzing what factors might determine the growth rate of regional average income levels and the net migration rates. Our results suggest a negative dependence between the initial average income level and the subsequent income growth, which supports the conditional convergence hypothesis. Among other things, we also find that the initial endowments of human capital have a positive effect on subsequent net migration while the initial unemployment rate is found to have a negative impact on net migration.Paper [5] complements the analysis made in Paper [4] by studying which factors determine average income growth and net migration at the local level of government. The conditional convergence hypothesis cannot be rejected. Local government investments are found to have a positive effect on the subsequent net migration while leaving the growth in mean income unaffected. This may indicate that the net migration caused by these investments does not significantly affect the proportion of skilled and unskilled labor.

Härtill 5 delarbeten.

digitalisering@umu

Cette recherche de doctorat étudie la relation entre la gestion informelle des risques de subsistance et l’allocation des terres agricoles. La gestion informelle des risques de subsistance est analysée ici comme explication potentielle de l'échec des politiques foncières de marché, et de la persistance de modes d'échanges `non-marchands'. En particulier, nous montrons que la vision bipolaire de l'allocation des terres opposant marchand et non-marchand n'est pas toujours pertinente pour l'analyse de la gestion des risques dans les pratiques foncières. Deux hypothèses sont analysées: en l'absence de moyens d'assurance publique ou privée, la terre prend une valeur de sécurité sociale qui peut détourner les ménages de la vente et leur faire préférer des transferts non-marchands ou temporaires, protégeant mieux la valeur assurance de la terre. Ensuite, des pratiques foncières hybrides, ni purement marchandes ni non-marchandes, se développent pour combiner la gestion des risques de subsistance avec d'autres motivations économiques. Ces hypothèses sont étudiées dans deux contextes: au Vietnam d'abord où les ménages les plus stables ou ceux subissant des chocs sévères vendent leur terre. En Thailande ensuite où, grâce à des données collectées sur le terrain, nous confirmons le rôle des stratégies de gestion des risques de subsistance dans l'activité ralentie des marchés de vente, et identifions ces fameuses pratiques foncières hybrides (ici des locations déguisées) . En conclusion, le développement de la protection (privée ou publique) des moyens de subsistance pourrait jouer un rôle privilégié dans l'évolution des modes d'allocation foncière
This PhD research proposes to study the relationship between informal risk-coping strategies and the nature of land allocation. Informal risk-coping mechanisms are studied here as one potential factor in the failure of land market reforms and the persistence of `non-market' exchange -gifts or free loans. In particular, we show that the bipolar view of land tenure, which opposes `customary' to `market' transfers, does not adequately approach informal risk-coping motivations in land transfers. Two hypotheses are analysed: first, in the absence of insurance markets and public social protection, land has a `safety net' function and households do not sell land but prefer other types of transfers (which retain part of the land's `safety net' function). Secondly, informal risk-coping leads households to participate to hybrid forms of transfers (neither market nor non-market) allowing to combine risk-coping motives with other types of economic necessities. Those two hypotheses are then looked at empirically in two case studies: in Vietnam, where households sell their land only if they are economically stable or have suffered income shocks (distress sales); and in Thailand, where a survey has been done among permanent rural-urban migrants. This surveyconfirms that informal risk-coping slows down land sale markets and sustains transfers such as free-loans. Finally, the Thai data identify traditional risk-sharing institutions in the allocation of land, especially through intra-family free-loans or `disguised rentals'. As a main conclusion, insurance and public protection policies could have a key role in the evaluation of land allocation systems in Thailand and Vietnam

博士
慈濟大學
醫學科學研究所
104
Abstract Hepatocyte growth factor (HGF) and its receptor c-Met were frequently deregulated in hepatocellular carcinoma (HCC). Signaling pathways activated by HGF-c-Met are promising targets for preventing HCC progression. HGF can induce the reactive oxygen species (ROS) signaling for cell adhesion, migration and invasion of tumors including HCC. On the other hand, extracellular signal-regulated kinases (ERK), member of mitogen activated kinase, can be activated by ROS for a lot of cellular processes. As expected, HGF-induced phosphorylation of ERK and progression of HCC cell HepG2 were suppressed by ROS scavengers. By N-(biotinoyl)- N′-(iodoacetyl)-ethylenediamine (BIAM) labeling method, a lot of cysteine (-SH)- containing proteins with M.W. 50–75 kD were decreased in HepG2 treated with HGF or two other ROS generators, 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and phenazine methosulfate(PMS). These redox sensitive proteins were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Among them, two chaperones, heat shock protein 60 (HSP60) and protein disulfide isomerase (PDI), were found to be the most common redox sensitive proteins in responding to all three agonists. Affinity blot of BIAM-labeled, immunoprecipitated HSP60 and PDI verified that HGF can decrease the cysteine (-SH) containing HSP60 and PDI. On the other hand, HGF and TPA increased cysteinyl glutathione-containing HSP60, consistent with the decrease of cysteine (-SH)-containing HSP60. Moreover, depletion of HSP60 and PDI or expression of dominant negative mutant of HSP60 with alteration of Cys, effectively prevented HGF-induced ERK phosphorylation and HepG2 migration. In conclusion, the redox sensitive HSP60 and PDI are required for HGF-induced ROS signaling and potential targets for preventing HCC progressions. Keywords: Hepatocyte growth factor; hepatocellular carcinoma; reactive oxygen species; extracellular signal-regulated kinases; heat shock protein 60; protein disulfide isomerase.

The purpose of this study was to explore how living outside of the passport country during the developmental years affected the experiences of adult Third Culture Kids (TCKs). Individual interviews were conducted with 15 adult TCKs who had lived at least one year outside of their passport country prior to age 18 and had returned to their passport country for at least one year. They were asked questions about how their experiences living outside of their passport country affected them. Data analyzed from the interviews generated 13 themes: (a) broader understanding of the world and the differences of people, (b) developing a support system of genuine relationships based on support and understanding, (c) development of an identity that integrates experiences and cultures, (d) feeling misunderstood, isolated, and different, (e) experience resulted in opportunities and skills sets that are not traditional in the passport country, (f) challenges of returning to the passport country, (g) internal struggles in relating to others and developing effective coping skills, (h) ability to negotiate change and a lack of fear of change, (i) difference in understanding of wealth and financial management, (j) view experience as positive and life-changing, (k) challenges in adjusting to a different culture, (l) variation in relationships with family, and (m) desire to travel and be in other places. These themes and their repeating ideas generated a grounded theory about the experiences of TCKs. This theory represents the relationships between the themes and the research questions. The theory consisted of six elements: (a) development of a global perspective, (b) affirmation of the complexity of relationships, (c) struggle to achieve cultural efficacy, (d) confirmation of the value of the experience, (e) challenge of acculturation, and (f) change as a source of achieving equilibrium. Findings from this study demonstrated that the experience of growing up outside of the passport country during the developmental years was perceived as a valuable and beneficial experience that significantly affected the participants. The results also identified challenges of the TCK experience and the influences these had in participants’ lives. Research and practice implications are presented. Results of this study may assist mental health professionals to understand the term TCK and the challenges with which they may present for treatment.
Department of Counseling Psychology and Guidance Services

The research has been designed to study the effects of the rapid urbanization in and around the Roodepoort, targeting mainly the sprawling informal settlements across the area and the existing townships of Dobsonville, Doornkop (Snakepark) and Kagiso. The researcher, who is a practising pastor in the area, had been challenged by a number of issues related to the process of urbanization. The CODESA process that culminated with the elections of 1994 and the subsequent change of government had raised very high hopes among the majority of South Africans who lived in poverty and foreigners, in their own land, for decades. The turnover at the elections, inspired by leaders such as Bishop Desmond Tutu, was a clear indication that an ordinary South African was yearning for a better life. This was a new beginning as many people had been restricted by the apartheid laws to work and live where they wanted. The repeal of all the apartheid laws saw the beginning of influx from the rural homelands to the cities. The hope that job opportunities were available near the cities was the main force of attraction. This unplanned process resulted in creation of massive informal settlements as there were no houses to cater for the massive movement. This process is called rapid urbanization. Not very long, the reality of the past indicated that there were no major changes with the new government. The economy still remained in the hands of few individuals, majority of whom still being white, as the new government came through negotiations and not complete take over (Coup D’état.) Few blacks managed to shoot up the economy ladder through processes such as BEE and the GEAR leaving the majority of people in abject poverty. The great trek did not only happen within the borders of the country, millions of people from the African, Asian and East European countries also moved into South Africa to try their luck at the new South African economy. Highly qualified professionals left their struggling countries to seek better life in South Africa. This category came legally through the recruitment processes but the larger contingency came illegally into the country. They took the advantage of lack of internationally recognised immigration instruments to regulate movement in and out of the country. This process saw the country soaring with illegal economic migrants as well as genuine refugees and asylum seekers. The rapid urbanization process brought about the following challenges:

• Culture shock
• Declining family structures/ life and Social problems
• Drug trafficking
• Education
• Exploitation of foreigners
• Exploitation of informal settlement dwellers and “Shack farming”
• Human trafficking.
• Inadequate housing and homelessness
• Institutional harassment and unfair discrimination
• Lack of Employment
• Poverty in urban areas
• Refugees and economic migrants
• Social benefit exclusion
• Stigmatization on HIV and AIDS, Crime, including serious crimes
• Xenophobia

The challenges, as tabled above, brought about a series conflicts between the South African internal migrants and the foreigners which culminated into a bitter xenophobic outburst of 2008. The main reason for the conflict was that South Africans felt that jobs were being taken away by foreigners and also that the government was neglecting service provision to the local community in favour of foreigners. A number of service delivery protests have become a common sight, particularly in the informal settlements. Lack of basic facilities and the irregular allocations of the RDP Houses, crime and poverty have waned the patience of residences of informal settlements. The resent protests in Zandspruit, Rietfontein and Diepsloot informal settlements north west of Johannesburg are some of the concrete examples. The situation could not be ignored by the Church and this research was an attempt to understand the extent of the problem in order to find a way to improve ministry to the affected communities.
Thesis (PhD)--University of Pretoria, 2012.
Practical Theology
unrestricted

I vulcani in stato di attività persistente a condotto aperto spesso ospitano un’attività definita stromboliana. Questo stile di attività è caratterizzato da rilasci frequenti (intervalli da secondi a minuti) e impulsivi (della durata di alcuni secondi) di piroclasti e gas, dovuti alla risalita e allo scoppio di grosse bolle di gas (dette slug) vicino alla superficie della colonna di magma. Nel tempo, tali vulcani possono mostrare continui cambiamenti nell’evoluzione e nella migrazione delle proprie bocche attive, dalle quali si può osservare anche un comportamento altamente variabile dell’attività. Le origini di tale variabilità devono essere studiate a scale spaziali e temporali variabili. In una scala di anni/centinaia di metri, l’osservazione diretta della migrazione delle bocche nello spazio e nel tempo nei vulcani contraddistinti da più bocche è ancora limitata, e resta da capire la relazione tra questa attività variabile e il sistema di condotti superficiale. Su una scala di secondi/metri, molti autori si sono focalizzati sulla dinamica del rilascio di gas e sulle modalità di formazione dei piroclasti, finora trascurando ampiamente la dinamica di risalita dei piroclasti dalla profondità di rilascio, dove gli slug scoppiano, sino alla loro espulsione dalla bocca. Lo scopo del mio studio è la definizione delle relazioni tra i parametri fisici all’interno del condotto vulcanico e la loro influenza sulla modalità di espulsione dei piroclasti nelle eruzioni stromboliane, tenendo conto delle due scale sopramenzionate. Per raggiungere tale scopo ho adottato due metodologie separate ma complementari. La prima richiede la caratterizzazione delle eruzioni stromboliane in natura, indagando i cambiamenti temporali nella posizione delle bocche sulla terrazza craterica di Stromboli e i parametri di esplosione (durata e geometria del getto) usando i video delle telecamere di sorveglianza a infrarossi raccolti tra il 2005 e il 2009. I risultati di questa prima metodologia forniscono un database dettagliato dell’attività stromboliana normale a diverse scale temporali, oltre a consentire di delineare una gerarchia di profondità a cui il sistema di condotti superficiale controlla l’attività esplosiva entro le tre principali aree (cioè la nord-est, la centrale e la sud-ovest) che raggruppano più bocche vicine a Stromboli. Alla profondità più bassa, dove gli slug scoppiano, la forma della bocca e le dimensioni degli slug controllano i parametri di esplosione locali, mentre la ramificazione più in superficie dei condotti determina l’evoluzione delle bocche che esplodono simultaneamente o alternativamente. Al di sotto della profondità di scoppio degli slug, il sistema di condotti che alimenta ciascuna area di bocche controlla quale specifica bocca ospiterà le esplosioni e anche alcune caratteristiche generali di esplosione all’interno di queste aree. A questa profondità si suppone ci sia un collegamento tra l’area centrale e quella sudovest, come supportato da diverse osservazioni. Al livello più profondo, il sistema di condotti è comune a tutte le aree e imposta il tasso eruttivo globale del vulcano, bilanciandolo tra l’area nord-est e quella congiunta sud-ovest e centrale. Questo tipo di analisi può essere eseguito anche in altri sistemi persistenti contraddistinti da più bocche in tutto il mondo, fornendo deduzioni di base sulla geometria e la dinamica del loro sistema di condotti e sulla valutazione della pericolosità connessa. La seconda metodologia è dedicata alle simulazioni di getti gas-particelle per mezzo di esperimenti analogici in scala utilizzando uno shock-tube trasparente. Questo approccio è incentrato sull’effetto delle condizioni iniziali (cioè, pressione e volume del gas, posizione del campione, dimensione e quantità di particelle, geometria della bocca) sia sull’accelerazione delle particelle all’interno del condotto che sull’espulsione risultante dalla bocca. I risultati mostrano che la velocità massima delle particelle ha una correlazione positiva con l’energia iniziale e una correlazione negativa sia con la profondità del campione rispetto alla bocca che con la dimensione delle particelle. Inoltre, gli esperimenti mostrano tendenze di accelerazione e decelerazione delle particelle all’interno dello shock-tube che dipendono in modo variabile da alcune condizioni iniziali (cioè energia iniziale, profondità del campione e dimensione delle particelle) e influiscono sulla velocità massima delle particelle registrata all’uscita. Rispetto ai processi che si verificano durante le eruzioni esplosive a piccola scala, questi risultati aprono la strada a nuove potenziali deduzioni riguanti i processi che controllano la dinamica dei piroclasti. Le tendenze di accelerazione e decelerazione all’interno dei condotti influenzano i modelli correnti che correlano la velocità di espulsione dei piroclasti con la loro profondità di origine nel condotto vulcanico. Dimostro che le assunzioni del modello non sono più valide nei casi di bassa energia iniziale e un campione più profondo. Pertanto, è necessaria una revisione del modello che tenga conto anche di queste tendenze prima di applicarlo alle eruzioni reali. Questi risultati aprono la strada a numerosi scenari futuri. Ad esempio, ulteriori esperimenti possono chiarire meglio gli effetti dell’accoppiamento gas- particella, analizzare il ruolo di altri parametri sull’espulsione dei piroclasti (ad esempio il diametro del condotto) o studiare altri aspetti (ad esempio, i pennacchi vulcanici utilizzando particelle molto fini, o collisioni particella-particella e particelle-parete nel condotto).
Persistent, open-vent volcanoes frequently host Strombolian explosions. This style of activity is characterized by frequent (intervals of seconds to minutes) and impulsive (seconds- long) releases of pyroclasts and gases, due to the rise and burst of large gas bubbles (i.e., slugs) near the surface of the magma column. Over time, such volcanoes can show continuous changes in the evolution and migration of their active vents, from which also a highly variable behavior of the activity can be observed. The sources of such variability need being investigated at variable spatial and temporal scales. On a scale of years/hundred of meters, direct observation of space-time vent migration at multi-vent volcanoes is still limited, and the relationship between this variable activity and the shallow conduit system remains to be understood. On a scale of seconds/meters, many authors are focused on the dynamics of gas release and modes of pyroclasts formation, so far largely neglecting the ascent dynamics of pyroclasts from their release depth, where slugs burst, to their ejection from the vent. The aim of my study is the definition of the relationships between the physical parameters inside the volcanic conduit and their influence on the modes of pyroclast ejection in Strombolian explosions, accounting for the two scales abovementioned. To achieve this aim, I considered two separate yet complementary methodologies. The first one requires the characterization of Strombolian eruptions in nature investigating temporal changes in vent position at the crater terrace of Stromboli and explosion parameters (jet duration and geometry) using infrared surveillance camera videos collected between 2005 and 2009. Results by this first methodology provide a detailed database of normal Strombolian activity at different time-scales, as well as allowing one to outline a hierarchy of depths at which the shallow conduit system controls the explosive activity within the three main vent areas (i.e., south-west, central, and north-east) at Stromboli. At the shallowest depth, where slugs burst, vent shape and slug size control local explosion parameters, while shallower conduit branching determines the evolution of simultaneous or alternating twin vents. Below the depth of the slug burst, the conduit system feeding each vent area controls which specific vent will host the explosions and also some more general explosion features within a vent area. A link between the central and south-west vent areas is supposed at this depth, as supported by several observations. At the deepest level, the conduit system is common to all vent areas and sets the overall explosion rate of the volcano, balancing it between the north-east and the joint south-west and central vent areas. This kind of analysis may be performed also in other persistent multi-vent systems worldwide, providing basic inferences on geometry and dynamics of their conduit systems and on the hazard assessment. The second methodology is addressed on gas-particle jet simulations by means of scaled analogue experiments using a transparent shock-tube. This approach focuses on the effect of the initial source conditions (i.e., gas pressure and volume, sample position, size and amount of particles, vent geometry) both on the acceleration of the particles within the conduit and on the resulting ejection from the vent. Results show that maximum particle velocity has a strong positive correlation with initial energy and a weaker, negative correlation with both sample depth from the vent and particle size. Moreover, the experiments show trends of particle acceleration-deceleration in the shock-tube that variably depend on some initial conditions (i.e., initial energy, sample depth, and particle size) and influence particle maximum velocity recorded at the exit. When compared to processes occurring during low-scale explosive eruptions, these results open the way for potential, new inferences on the processes controlling the dynamics of pyroclasts. The acceleration-deceleration trends inside the conduits impact current models relating pyroclast ejection velocity with their source depth in the volcanic conduit. I show that, for a lower initial energy and a deeper sample, the model assumptions do not hold true anymore. Therefore, a model revision taking into account these trends is necessary before applying it to real eruptions. These results open the way to numerous future scenarios. Further experiments may, for instance, clarify, the effects of particle-gas coupling, analyze the role of other source parameters on pyroclast ejection (e.g., conduit diameter) and study other aspects (e.g., the volcanic plumes using very fine particles, or particle-particle and particle-wall collisions in the conduit).