This research investigates the relationship between the success of a regional economy – particularly that of the Yorkshire and the Humber region - and the adequacy or otherwise of its logistics infrastructure and services, in order to determine how regional competitiveness can be enhanced through the provision of effective logistics services. The theory of business cluster formation and development has been employed as a linking point between logistics and regional development. The research undertaken for the literature review and in the later stages of the original investigations has led to the identification of a number of knowledge gaps in the assessment of the transport and logistics implications of cluster development for the regional economy. Data collection encompassed two questionnaire surveys of users and providers of freight transport and logistics services in Yorkshire and the Humber, followed by a series of case studies. These original investigations contributed to the extension of an existing supply chain mapping technique by incorporating a regional or spatial dimension for the first time and the development of a Regional Index of Supply Chain Activity (RISCA). The information gathered, analysed and evaluated in all stages of this research (the literature review, the surveys and case studies), when considered in its entirety, presents a conceptual framework (which can also be regarded as a decision-support tool) for identifying a best practice approach to achieving improved regional economic competitiveness through logistics. This enables regional governments to develop a much improved understanding of the extent to which supply chains add their maximum possible value to the economies of their regions and to put in place adequate business support measures to ensure that the regional freight and logistics providers are delivering services more closely aligned to the diverse and often specialised needs of users.

Despite the fact that in a general logistics context, value-adding services (VAS) have been acknowledged in various publications, there is a dearth of available empirical works that have particularly investigated the competitive capacity of these services in the formulation of port strategy. Hence, the development of models that are useful to understanding and assessing the capacity of value-adding services in port strategies is necessary to bridge this knowledge gap. In the context of this study, value-adding services are defined as customised and additional services which complement the core or main offerings of a firm. A critical realist approach to research was deployed. Questionnaires were used to survey port users, while in-depth interviews were carried out with port management of the multiple case study ports. The case study ports were Rotterdam (The Netherlands), PD Teesport (United Kingdom), Damietta (Egypt) and Apapa (Nigeria) ports. Ten key value-adding services were identified. The research showed that value-adding services may provide a useful input into the competitive strategy of attracting and retaining port users to a port. The services were found to offer opportunities for the diversification of business for port authorities and port operators. Original contributions of the study include that it brings to the maritime logistics body of knowledge an understanding of the importance of the different value-adding services, principally based on port users‟ assessment. In sequence, the most important value-adding services were transport service, warehousing, water supplies and technical support, whilst the least important services were canteen/catering and advertising support services. Hitherto, there is no published study that has provided insight into the importance port users attach to various value-adding services. In port strategy formulation by the deployment of value-adding services, there is a stage in which dynamism sets in and the uniqueness of the services tend to wear-off, requiring concerted rejuvenation to sustain the potential of value-adding services in competitive strategies. The main challenging issues to port management in the deployment of value-adding services in strategy were found to be concerned with legislation, availability of traffic (cargo and vessel), duration of contracts, adequate land and space availability. The study also developed models, one to stimulate theoretical understanding of port value-adding services, the other to facilitate informed decision-making on the viability of offering value-adding services in ports.

The theory of resource dependence captures the extent to which a country’s economy relies on resource rents. It is usually measured in proportion to GDP, exports, or government revenues; hence, it is a function of absolute levels of resource extraction and rent capture in the context of other economic activity and sources of state revenue. This study has focused on the efforts to date by Libya to diversify its economic base. The resource dependence observed in Libya’s economy is driven mainly by the fact that there are relatively few alternative forms of economic activity, as evidenced by a per capita gap in GDP, or a low level of other exports. The state’s fiscal reliance on revenues from the extractive industries also depends on the size of other revenue streams. Yet, Libya has been unable to adequately distribute its GDP across a wide range of productive sectors. This concern highlights the earlier awareness to the risks of oil resource depletion which could compromise the future of the Libyan economy. In-depth interviews, and semi-structured questionnaire data analysis were carried out to obtain an actual view of the respondent’s perception. The study found that to achieve its objective of sustainability, Libya will need to ensure natural resources continue to be managed efficiently into the future. This may require some policy adjustments. First, diversifying the economy towards higher value-added tasks in manufacturing and services requires renewed emphasis on the structural reform agenda, as well as enhancements to public investment management. These will create the necessary conditions for accelerate productive investments in non-commodity sectors. The formation and the implementation of the policy were consistent with the analysis suggested by literature review. A series of recommendation to improve on the policy was made based on the analysis of the problems indicated and based on suggestions from respondents.

Government debt management, as a distinct policy, with a clear objective of managing risks and cost minimisation first started among the industrialised economies in the late 1980s. The need to improve government debt management arose with rising debt levels, caused by macro-economic imbalances especially in the mid-1970s and 1980s. In sub-Saharan Africa however, debt management as a strategy was undeveloped or lacking completely. A research in the area of debt management is significant to the economic growth and development of the sub – Saharan Africa. The significance of debt management is supported by empirical studies showing that effective public debt management could go a long way in protecting both low and middle income countries against the negative impact of the financial crisis. This research focus specifically on the choice between short and long term, domestic and external debts and how the process affects the economy as measured by per capita income and debt ratio or level of indebtedness. The work also looked at the extent of implementation of debt management among the SSAs especially as contained in the World Bank and IMF debt management performance guidelines. The research adopted the quantitative approach to answer questions raised in relation to the effect of government borrowing; the choice of debt maturity, and how sovereign debt and its management affect economic growth. It was found that debt is related negatively to economic growth; and the phenomenon of debt overhang actually exists. Debt management however was found to be relevant; where it was observed that the entire process of debt management is vital to economic growth and the development of a country. In particular, countries in sub-Saharan Africa need to put in place an effective and sound debt management strategy that would aid in promoting the needed stability, reduce risks in borrowing and guide in the prudent management of borrowed resources. The work contribute to both theoretical and empirical aspects of debt and its management.

Les crédits que l’on accorde pour l’achat de biens et services, par exemple les automobiles et les équipements de la maison, s’appellent des crédits à la consommation. Il est important de savoir que depuis trois décennies on constate une baisse du taux d’épargne au Canada et, en contrepartie, une hausse de l’endettement des ménages, et plus particulièrement une hausse des crédits à la consommation. À quoi est due cette hausse des crédits à la consommation? Et quel est l’impact de cette hausse sur l’économie canadienne? Cette analyse se base sur la Théorie du Revenu Permanent. Celle-ci stipule que les choix effectués par les consommateurs sont dictés non pas par leur revenu effectif actuel, mais par leur estimation de revenu permanent. Une implication est que les individus souhaitent lisser leur consommation dans le temps. Les emprunts seront donc reliés aux fluctuations du revenu autour de ce revenu permanent. Pour estimer cette relation, nous réalisons une régression avec correction d’erreur qui nous permet de calculer l’équilibre stationnaire et de court terme. Une équation de forme réduite est estimée. Pour les facteurs influençant la demande de crédit, nous considérons la richesse totale des ménages (financière, humaine et immobilière) et le taux d’intérêt. Du côté de l’offre, la perception du risque des banques est un facteur à considérer. En somme, cette étude cherche à comprendre quelles sont les causes de l’augmentation du crédit à la consommation au Canada. Notre analyse montre que cette hausse est due à une augmentation de la richesse globale (humaine, financière et Immobilière) des ménages et au fait que les emprunts ne semblent pas réagir autant à la baisse lorsque ces variables diminuent.

La présente recherche porte sur les relations de court terme entre les rendements boursiers et l'inflation au Canada. Les tests de l'hypothèse de Fisher, repris empiriquement par Fama et Schwert (1977) et Cozier et Rahman (1988), ainsi que l'examen des relations ex-post sont effectués sur des données trimestrielles. Le travail empirique a porté sur l'ensemble de la période allant de 1962 à 2015 et sur les sous-périodes avant et après l'introduction de la politique de ciblage de l'inflation par la Banque du Canada en 1991. Les bons du trésor à échéance dans trois mois et les modèles ARIMA sont mis à contribution pour estimer les composantes anticipée et non anticipée de l'inflation. L'hypothèse de Fisher n'est pas vérifiée au Canada sur l'ensemble de la période d'étude ; les corrélations entre les rendements nominaux et l'inflation anticipée sont négatives mais non significatives. L'effet de l'inflation anticipée et non anticipée sur les rendements réels entre 1962 et 2015 se distingue de celui qui a été mis en évidence dans les travaux antérieurs et lors de l'analyse de la sous-période avant l'introduction du ciblage de l'inflation. L'introduction du ciblage de l'inflation coïncide avec des changements dans les relations expost. L'inflation réalisée et rendements boursiers évoluaient en sens inverse avant l'introduction du ciblage de l'inflation de manière significative (rendements réels) ou non significative (rendements nominaux). Depuis le second trimestre de 1991, la relation empirique est positive avec un effet plus que proportionnelle de l'inflation réalisée sur les rendements boursiers. En situation de faible et stable inflation, les rendements boursiers permettent largement de se prémunir contre l'inflation réalisée.

Om en gäldenär har fler än en skuld till samma borgenär och betalar ett belopp som inte är stort nog att täcka samtliga skulder, uppstår frågan på vilken av skulderna betalningen ska avräknas. Vad gäller frivillig betalning regleras situationen av 9 kap. 5 § i 1736 års handels-balk (HB), som tillerkänner gäldenären en primär rätt att välja avräkningsskuld. Ur 9 kap. 5 § HB går det inte att utläsa vad som händer när gäldenär inte gör något val. Ur rättspraxis och rättsvetenskaplig doktrin har det därmed vuxit fram en princip som tillmäter borgenär en sekundär valrätt vid odestinerade betalningar. Att tilldela gäldenär en primär valrätt när denne har flera skulder till samma borgenär före-faller vara en närmast universell princip. Det förklaras ofta med att gäldenär har full ägande-rätt över sin förmögenhet och får bruka denna på ett sätt som denne finner mest lämpat. Ut-över gäldenärs intresse av särskild avräkningsordning går det även att finna andra intressen bakom avräkningsordningen. Ett av dessa intressen är omsättningsintresset, det vill säga att regleringen ska vara enkel och effektiv att använda samt verka konfliktminskande. Ur praxis har även borgenär tillmätts ett särskilt intresse av en viss avräkningsordning och detta intresse har visats kunna väga tyngre än gäldenärens dito. Trots lagrummets aktningsvärda ålder är fortfarande ett flertal frågor angående avräknings-ordningen obesvarade. I doktrin förekommer inte sällan skiljaktiga meningar om rättsläget. Även på vilket sätt avräkningsordningen bör förändras har framförts olika åsikter om, fram-förallt hur den sekundära valrätten bör utövas. Genom att analysera de olika bakomliggande intressena och att applicera dessa på framförda reformförslag samt även undersöka huruvida förslagen löser några av dagens problem, avser jag att framföra den modell jag anser är bäst lämpad i svensk rätt. Justitieråden Lindskog och Johansson förespråkar ett system där valrätten inte övergår på borgenären förrän denne frågat gäldenären om vilken skuld gäldenären vill avräkna. Justitie-rådet Herre vill däremot se att Sverige inför en bestämmelse likt den i DCFR, som bland annat innehåller en förbestämd avräkningsordning som aktualiseras i det fall borgenären inte utnyt-tjar sin destinationsrätt inom skälig tid. Före detta justitieråden Walin och Karlgren erkänner inte ens borgenärers sekundära valrätt och anför en skyldighet för borgenär att alltid avräkna den för gäldenären mest betungande skulden. Behovet av reform av 9 kap. 5 § HB är idag inte lika stort som tiden före instiftandet av en gäldenärsvänlig skyddsregel i NJA 2013 s. 1190. Däremot finns det fortfarande en stor för-bättringspotential av avräkningsordningen. Enligt min uppfattning utgör inte Walins och Karl-grens förslag en lämplig grund för reform, eftersom borgenärs sekundära valrätt idag är fast cementerad i svensk rätt och att förslaget inte tar hänsyn till borgenärs intresse vid avräkning. Lindskogs och Johanssons modell med avräkningsförfrågan, anser jag inte heller balanserar de bakomliggande intressena på ett valavvägt sätt, eftersom den är alltför gäldenärsvänlig. Bestämmelsen i DCFR skulle däremot – efter viss modifikation – främja omsättningsintresset på ett lämpligt vis och samtidigt ta hänsyn till både gäldenärers och borgenärers intressen på ett fördelaktigt sätt.

L’endocytose dépendante de la clathrine (EDC) est la principale voie d’internalisation des récepteurs de surface et de leurs ligands. L’internalisation se fait suite à l’invagination de la membrane plasmique vers l’intérieur de la cellule suite à la formation, dans un premier temps, de puits recouverts de clathrine (PRCs) qui bourgeonnent ensuite en vésicules recouvertes de clathrine dans le cytosol. L’EDC est un processus très dynamique qui a lieu en l’espace de 30 sec-1mn. Elle est impliquée dans de multiples fonctions et permet ainsi à la cellule de réguler l’expression de ses protéines en surface, de répondre aux signaux de prolifération ou migration envoyés par l’environnement immédiat via l’activation de voies de signalisation spécifiques ou encore de réguler le renouvellement des composants de la membrane plasmique. De par son importance, des dérégulations de l’endocytose dépendante de la clathrine ont déjà été observées dans les cancers. Ces modifications peuvent impliquer directement l’EDC en modifiant ses composants ou indirectement lors d’altérations de récepteurs régulés par celle-ci. La progression tumorale est elle-même régulée par de multiples facteurs, notamment l’accumulation de mutations qui ont des conséquences sur les cellules cancéreuses elle-même ou bien sur l’environnement immédiat, formant ainsi la « niche tumorale ». Ces changements agissent réciproquement sur la progression tumorale afin de l’amplifier. Lors de la croissance tumorale, les cellules cancéreuses recrutent des fibroblastes qui vont participer au remodelage et à l’augmentation de la rigidité autour de la tumeur. La rigidité de la matrice extracellulaire est détectée par les cellules ce qui envoie des signaux déclencheurs de prolifération et de migration en conséquence. Cette détection passe essentiellement par les intégrines à la surface membranaire qui vont s’agréger et induire des cascades de signalisation impliquées dans ces réponses. Ces intégrines peuvent se regrouper dans deux types de structures, les adhésions focales et les structures recouvertes de clathrine. En ce qui concerne ces dernières, il a été démontré précédemment que la rigidité du substrat augmente sa force d’interaction avec les intégrines, et empêche ainsi l’internalisation des vésicules recouvertes de clathrine, on parle alors d’ « endocytose frustrée ». Cette rétention des structures recouvertes de clathrine à la surface provoque une signalisation soutenue à la surface au lieu de l’arrêter par dégradation ultérieure des récepteurs dans les lysosomes. Le laboratoire a démontré que les structures de clathrine frustrées capturent ainsi différent récepteurs conduisant à une signalisation accrue dans la voie de la MAP Kinase Erk. Mon projet de thèse repose sur ces observations en s’intéressant plus particulièrement au rôle d’une autre modification induite par la croissance tumorale, le confinement. En effet, en se multipliant de manière incontrôlée dans un environnement spatialement restreint, les cellules tumorales se retrouvent soumises à des forces de compression. Les résultats mis en évidence au cours de ma thèse ont montré que le confinement provoque, comme la rigidité, une frustration des structures de clathrine qui ne sont donc plus capables de soutenir l’endocytose des récepteurs. De plus, la compression cellulaire induit le clivage d’un pro-ligand de l’EGFR, le HB-EGF, ce qui conduit à l’activation paracrine de l’EGFR et à l’activation de la voie Erk. En effet, l’absence de facteurs de croissance dans le milieu ainsi que l’inhibition de ce clivage démontrent la nécessité de la mise en place de ce mécanisme. En résumé, le confinement induit le clivage du pro-ligand HB-EGF, qui à son tour va activer le récepteur à l’EGF. En parallèle, l’endocytose est ralentie et provoque une signalisation accrue à la membrane. Ces deux évènements coopèrent pour mener à une très forte activation de la voie Erk. / Clathrin-mediated endocytosis (CME) is the major route of endocytosis for many cargos in eukaryotic cells. Endocytosis takes place at clathrin-coated pits (CCPs), small assemblies of clathrin and clathrin adaptors randomly distributed at the plasma membrane. Clathrin polymerization induces the progressive bending of the plasma membrane resulting in the formation of a vesicle budding off into the cytosol. CME is a highly dynamic process with an average lifetime of CCPs in the order of 30 seconds. In this manner, CME fulfills a range of different functions and enables cells to regulate the surface expression of proteins, to sample the cell’s environment for growth and guidance cues, to control the activation of signaling pathways and to turn over membrane components by sending these components for degradation in the endo-lysosomal pathway. A deregulation of the endocytic pathways was previously shown to be involve in cancer. These modifications can affect CME directly by modifying its actors, or indirectly with mutations on receptors or cargoes undertaken by CME. Tumor progression is dependent of several factors, the first one involving the accumulation of mutations which results in modifications in the cells themselves or on their surrounding environment by changing its biochemical and physical properties, leading to the formation of the tumor niche. These changes reciprocally foster cancer progression. During tumor growth, fibroblasts will be recruited around tumor cells, leading to the remodeling of the microenvironment and to an increase of rigidity nearby the tumor. This stiffness is sensed by the cells and send signals for proliferation and migration as a result. Stiffness sensing engages mainly integrins at the cell surface which will aggregate and initiate signaling cascades accountable for these responses. Integrins are capable of clustering into two types of structures: focal adhesions and clathrin-coated structures (CCSs). Regarding CCSs, it was shown previously that high stiffness strengthen the interaction between integrins and the substrate, hence preventing the budding off of the vesicle, and this is referred to as “frustrated endocytosis”. This holding of CCSs at the cell surface promotes a sustained signaling at the plasma membrane instead of a signal termination after internalization and further degradation in lysosomes. My PhD project relied on these previous findings, with a particular focus on another mechanical alteration observed in tumors, the confinement. Indeed, during the uncontrolled proliferation of cancer cells in a spatially restricted area, cells become subjected to compressive forces. The results I obtained indicate that confinement leads to frustrated endocytosis and hence to sustained signaling from the plasma membrane. In addition, compression also leads to HB-EGF shedding at the cell surface, and the resulting EGF product activate the EGFR in a paracrine manner, thus leading to the activation of the MAP kinase Erk signaling pathway. Indeed, both the absence of EGFR ligands in the medium and the inhibition of the shedding demonstrate the necessity of this mechanism in EGFR activation. To sum up, confinement induces the shedding of the EGFR pro-ligand HB-EGF necessary to EGFR activation in these conditions. Simultaneously, endocytosis is delayed and frustrated endocytosis leads to sustained signaling at the cell surface. Together, these events cooperate to strongly activate the Erk pathway. These findings highlight the interplay between the physical feature of the tumor environment and signaling pathways known to govern tumor growth.

I present three essays on income taxation in Pakistan. The first essay investigates how taxes influence agents’ earnings, compliance and business organization choices. Using a tax reform introduced in Pakistan in 2010, which raised tax rates on partnership earnings as compared to sole proprietorship income, as a natural policy experiment, I (i) identify a full range of behavioral responses to the tax rate changes (ii) study the determinants of tax compliance (iii) investigate if VAT causes firms to be more tax compliant. Relying on administrative tax records that comprise the universe of income tax returns filed in 2006-11 and a rich set of firm characteristics, I find that the reform induced substantial extensive and intensive margin responses including reduction in earnings, income shifting, movement into informality, and spillover effects on VAT base. I also find that the firms that have greater fraction of their tax withheld at source, are registered for VAT, or withhold taxes of other agents are more tax compliant. This highlights the importance of the notion that information trails on arm-length business transactions facilitate enforcement. Comparing short-term responses of partnership firms – which arguably identify tax evasion – on both sides of the VAT exemption threshold, I find that the evasion changes discontinuously at the cutoff suggesting that the VAT causes firms to be more compliant. In the second essay, I along with my co-authors, analyze the design of tax systems under imperfect enforcement. A common policy in developing countries is to impose minimum tax schemes whereby firms are taxed either on profits or on turnover (with a much lower tax rate on turnover), depending on which tax liability is larger. This is a production inefficient tax policy, but has been motivated by the idea that turnover taxes are harder to evade. Such schemes give rise to kink points in firms’ choice sets as the tax rate and tax base jump discontinuously at a profit rate threshold. Analyzing responses to one such scheme in Pakistan, we find large bunching of corporate firms around the minimum tax kink. We show that the combined tax rate and tax base change at the kink provides small real incentives for bunching, making the policy ideal for eliciting evasion. Based on the methodology that we develop, we estimate that turnover taxes reduce evasion by up to 60-70% of corporate income. In the third essay, I along with Henrik Kleven, develop a framework for non-parametrically identifying optimization frictions and structural elasticities using notches – discontinuities in the choice sets of agents – introduced for example by tax and transfer policies. We apply our framework to tax notches in personal income tax schedule of Pakistan to estimate structural elasticities of taxable income.

Empirical studies in labour economics often suffer from endogeneity problems. Employing exogenous variations in policies and natural shock, this thesis investigates three topics. The �first two topics concern labour market phenomena in Thailand, whereas the third provides a case study of labour demand adjustment after an international supply chain shock. Chapter 2 assesses the impact of minimum wage policy on wage inequality in Thailand. The result is rather mixed. Although the minimum wage effectively reduces wage inequality among workers in formal sectors, it does not affect the wage distribution in the informal sector at all. The evidence suggests that such a result is mainly driven by weak law enforcement. Meanwhile, using changes in compulsory schooling law, chapter 3 provides consistent estimates of the rates of return to education in Thailand. Based on the IV method, only female employees experience a positive and significant return to (upper primary) education. Interestingly, the size and direction of bias of the estimator, especially for male sub-sample, are not consistent with the conventional result. The possible reasons underlying these �findings are elaborated. Chapter 4 relies on a different type of shock. The Great Tohoku Earthquake and Tsunami 2011 is treated as an external shock to the international supply chain of Auto industry. Then I estimate the impact of the supply chain disruption on labour inputs adjustment in the US auto industry. Despite the break down in supply chain of motor vehicle parts and accessories among Japanese auto companies, these �firms do not seem to reduce their labour inputs (used as a proxy for changes in production) significantly except for a small drop in average monthly earnings of workers in Japanese assembly plants. Also, their competitors make only slight adjustment to capitalize on the Japanese loss. Regarding other margins of adjustment, there is no evidence in support of the adjustment through import or price. Yet inventories and sales incentive appear to be major tools employed to mitigate either positive demand or negative supply shocks on both groups of companies.