973 resultados para push-pull converter


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Members of the leucine-rich repeat protein family are involved in diverse functions including protein phosphatase 2-inhibition, cell cycle regulation, gene regulation and signalling pathways. A novel Schistosoma mansoni gene, called SmLANP, presenting homology to various genes coding for proteins that belong to the super family of leucine-rich repeat proteins, was characterized here. SmLANP was 1184bp in length as determined from cDNA and genomic sequences and encoded a 296 amino acid open reading frame that spanning from 6 to 894bp. The predicted amino acid sequence had a calculated molecular weight of 32kDa. Analysis of the predicted sequence indicated the presence of 3 leucine-rich domains (LRR) located in the N-terminal region and an aspartic acid rich region in the C-terminal end. SmLANP transcript is expressed in all stages of the S. mansoni life cycle analyzed, exhibiting the highest expression level in males. The SmLANP protein was expressed in a GST expression system and antibodies raised in mice against the recombinant protein. By immunolocalization assay, using adult worms, it was shown that the protein is mainly present in the cell nucleus through the whole body and strongly expressed along the tegument cell body nuclei of adult worms. As members of this family are usually involved in protein-protein interaction, a yeast two hybrid assay was conducted to identify putative binding partners for SmLANP. Thirty-six possible partners were identified, and a protein ATP synthase subunit alpha was confirmed by pull down assays, as a binding partner of the SmLANP protein.

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Despite the huge effort and massive advances toward the elimination of leprosy over the last two decades, the disease has proven stubborn; new case detection rates have stabilised over the last few years and leprosy remains endemic in a number of localised regions. The American Leprosy Missions and Infectious Disease Research Institute have undertaken a large research effort aimed at developing new tools and a vaccine to continue the push for leprosy elimination. In this paper, we outline our strategy for the integration of rapid diagnostic tests and lab-based assays to facilitate the detection of early or asymptomatic leprosy cases, as well as the efficient and focused implementation of chemoprophylaxis and immunisation to intervene in leprosy development and transmission.

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Résumé : Le virus tumoral de la glande mammaire de la souris (MMTV) est un rétrovirus provoquant le développement de tumeurs dans les glandes mammaires des souris susceptibles femelles. Au cours de son évolution, le virus s'est adapté et s'exprime dans des cellules spécialisées. Les lymphocytes B sont les premières cellules infectées et elles sont essentielles pour la propagation de l'infection aux glandes mammaires. Dans notre étude, le virus MMTV a été utilisé afin d'examiner les voies de signalisation induites par les glucocorticoïdes (dexaméthasone (dex), une hormone stéroïdienne) et le transforming growth factor-f3 (TGF-P, une cytokine), deux molécules impliquées dans l'activation de la transcription à partir du promoteur du MMTV dans les cellules B. Le TGF-P seul n'influence pas l'activité du promoteur du MMTV. Par contre, en synergie avec dex, le TGF-P provoque une super-induction de l'expression du promoteur par rapport à une stimulation par le glucocorticoïde seul. Cette super-induction est régulée par une famille de protéines, les Smads. Ainsi, dans les lymphocytes B, l'utilisation du MMTV a permis de mettre en évidence une nouvelle synergie entre les glueocortieoïdes et le TGF-p. pans ce travail, l'utilisation d'inhibiteurs pharmacologiques et de mutants « dominant-négatifs » nous a pet mis de démontrer qu'une Protéine Kinase C delta (PKC5) active est impliquée dans la transduction du signal lors de la réponse au dex ainsi que celle au TGF-P. Néanmoins, la PKC5 est régulée différemment dans chaque voie spécifique : la voie du TGF-p nécessitait l'activation du PKC5 par diacylglycerol (DAG) et la phosphorylation de tyrosines spécifiques, alors que la voie impliquant les glucocorticoïdes ne le nécessitait pas. Nous avons aussi démontré qu'une tyrosine kinase de la famille Src est responsable de la phosphorylation des tyrosines sur la PKC5. Les essais de kinase in vitro nous ont permis de découvrir que plusieurs Src kinases peuvent phosphoryler la PKC6 dans les cellules B et qu'elles étaient constitutivement actives. Enfin, nous avons montré qu'il existe une interaction protéine - protéine induite par dex, entre le récepteur aux glucocorticoïdes (GR) et la PKC5 dans les cellules B, une association qui n'a pas été démontrée auparavant. Par ailleurs, nous avons analysé les domaines d'interactions entre PKC5 et GR en utilisant les essais de «GST pull-down». Nos résultats montrent que le domaine régulateur de la PKC5 et celui qui interagit avec l'ADN du GR sont impliqués. En résumé, nous avons trouvé que dans une lignée lymphocytaire B, le virus MMTV utilise des mécanismes pour réguler à la fois la transcription et la voie de signalisation qui sont différents de ceux utilisés dans les cellules mammaires épithéliales et les fibroblastes. Nos découvertes pourraient être utilisées comme modèles pour l'étude de gènes cellulaires impliqués dans des processus tels qu'inflammation, immunité ou cancérogénèse. Summary: Mouse Mammary Tumor Virus (MMTV) is a retrovirus that causes tumors in the mammary glands of susceptible female mice and has adapted evolutionarily to be expressed in specialized cells. The B lymphocytes are the first cells to be infected by the MMTV and are essential for the spread of infection to the mammary glands. Here, we used the MMTV as a model system to investigate the signalling cascade induced by giucocorticoids (dexamethasone, "dex", a steroid hormone), and by Transforming Growth Factor-beta (TGF-P, a cytokine) leading to its transcriptional activation in B lymphocytes. By itself, TGF-I3 does not affect the basal activity of the MMTV promoter. However, TGF-13 significantly increases glucocorticoid-induced expression, through its effectors, the Smad factors. Thus, MMTV in B cells demonstrates a novel synergism between glucocorticoids and TGF-16. In this thesis project, we present evidence, based on the use of pharmacological inhibitors and of dominant-negative mutants, that an active Protein Kinase C delta (PKC6) is required as a signal transducer for the dex response and for the TGF-P superinduction as well. The PKC6 is differentially regulated in each specific pathway: whereas the TGF-13 superinduction required PKC6 to be activated by diacylglycerol (DAG) and to be phosphorylated at specific tyrosine residues, the glueocorticoid-induced pathway did not. We also showed that a protein tyrosine kinase of the Src family is responsible for the phosphorylation of tyrosines on PKC6. By performing in vitro kinase assays, we found that several Src kinases of B cells were able to phosphorylate PKC6 and that they were constitutively active. Finally, we demonstrate a dex-dependent functional protein-protein interaction between the glucocorticoid receptor (GR) and PKC6 in B cells, an association that has not been previously described. We further analysed the interacting domains of PKG6 and GR using in vitro GST pull-down assays, whereby the regulatory domain of PKC6 and the extended DNA-binding domain of the GR were involved. In summary, we found that in B-lymphoid cell lines, MMTV uses novel mechanisms of transcriptional control and signal transduction that are different from those at work in mammary epithelial or fibroblastic cells. These findings will be used as model for cellular genes involved in cellular processes such as immune functions, inflammation, or oncogenic transformation that may have a similar pattern of regulation.

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To further understand the pharmacological properties of N-oleoylethanolamine (OEA), a naturally occurring lipid that activates peroxisome proliferator-activated receptor alpha (PPARα), we designed sulfamoyl analogs based on its structure. Among the compounds tested, N-octadecyl-N'-propylsulfamide (CC7) was selected for functional comparison with OEA. The performed studies include the following computational and biological approaches: 1) molecular docking analyses; 2) molecular biology studies with PPARα; 3) pharmacological studies on feeding behavior and visceral analgesia. For the docking studies, we compared OEA and CC7 data with crystallization data obtained with the reference PPARα agonist GW409544. OEA and CC7 interacted with the ligand-binding domain of PPARα in a similar manner to GW409544. Both compounds produced similar transcriptional activation by in vitro assays, including the GST pull-down assay and reporter gene analysis. In addition, CC7 and OEA induced the mRNA expression of CPT1a in HpeG2 cells through PPARα and the induction was avoided with PPARα-specific siRNA. In vivo studies in rats showed that OEA and CC7 had anorectic and antiobesity activity and induced both lipopenia and decreases in hepatic fat content. However, different effects were observed when measuring visceral pain; OEA produced visceral analgesia whereas CC7 showed no effects. These results suggest that OEA activity on the PPARα receptor (e.g., lipid metabolism and feeding behavior) may be dissociated from other actions at alternative targets (e.g., pain) because other non cannabimimetic ligands that interact with PPARα, such as CC7, do not reproduce the full spectrum of the pharmacological activity of OEA. These results provide new opportunities for the development of specific PPARα-activating drugs focused on sulfamide derivatives with a long alkyl chain for the treatment of metabolic dysfunction.

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Non-structural protein 2 (NS2) plays an important role in hepatitis C virus (HCV) assembly, but neither the exact contribution of this protein to the assembly process nor its complete structure are known. In this study we used a combination of genetic, biochemical and structural methods to decipher the role of NS2 in infectious virus particle formation. A large panel of NS2 mutations targeting the N-terminal membrane binding region was generated. They were selected based on a membrane topology model that we established by determining the NMR structures of N-terminal NS2 transmembrane segments. Mutants affected in virion assembly, but not RNA replication, were selected for pseudoreversion in cell culture. Rescue mutations restoring virus assembly to various degrees emerged in E2, p7, NS3 and NS2 itself arguing for an interaction between these proteins. To confirm this assumption we developed a fully functional JFH1 genome expressing an N-terminally tagged NS2 demonstrating efficient pull-down of NS2 with p7, E2 and NS3 and, to a lower extent, NS5A. Several of the mutations blocking virus assembly disrupted some of these interactions that were restored to various degrees by those pseudoreversions that also restored assembly. Immunofluorescence analyses revealed a time-dependent NS2 colocalization with E2 at sites close to lipid droplets (LDs) together with NS3 and NS5A. Importantly, NS2 of a mutant defective in assembly abrogates NS2 colocalization around LDs with E2 and NS3, which is restored by a pseudoreversion in p7, whereas NS5A is recruited to LDs in an NS2-independent manner. In conclusion, our results suggest that NS2 orchestrates HCV particle formation by participation in multiple protein-protein interactions required for their recruitment to assembly sites in close proximity of LDs.

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The serine/threonine kinase WNK3 and the ubiquitin-protein ligase NEDD4-2 are key regulators of the thiazide-sensitive Na+-Cl- cotransporter (NCC), WNK3 as an activator and NEDD2-4 as an inhibitor. Nedd4-2 was identified as an interacting partner of WNK3 through a glutathione-S-transferase pull-down assay using the N-terminal domain of WNK3, combined with LC-MS/MS analysis. This was validated by coimmunoprecipitation of WNK3 and NEDD4-2 expressed in HEK293 cells. Our data also revealed that the interaction between Nedd4-2 and WNK3 does not involve the PY-like motif found in WNK3. The level of WNK3 ubiquitylation did not change when NEDD4-2 was expressed in HEK293 cells. Moreover, in contrast to SGK1, WNK3 did not phosphorylate NEDD4-2 on S222 or S328. Coimmunoprecipitation assays showed that WNK3 does not regulate the interaction between NCC and NEDD4-2. Interestingly, in Xenopus laevis oocytes, WNK3 was able to recover the SGK1-resistant NEDD4-2 S222A/S328A-mediated inhibition of NCC and further activate NCC. Furthermore, elimination of the SPAK binding site in the kinase domain of WNK3 (WNK3-F242A, which lacks the capacity to bind the serine/threonine kinase SPAK) prevented the WNK3 NCC-activating effect, but not the Nedd4-2-inhibitory effect. Together, these results suggest that a novel role for WNK3 on NCC expression at the plasma membrane, an effect apparently independent of the SPAK kinase and the aldosterone-SGK1 pathway.

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The first Rostock Debate on Demographic Change, which took place on February 21, 2006, centered on the following question: Should governments in Europe push much more aggressively for gender equality to raise fertility? The four debaters were Laurent Toulemon from the Institut National d'Etudes Demograhiques (France), Dimiter Philipov from the Vienna Institute of Demography (Austria), Livia Olah from Stockholm University (Sweden), and Gerda Neyer from the Max Planck Institute (Germany).

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The phytochrome family of red/far-red (R/FR)-responsive photoreceptors plays a key role throughout the life cycle of plants . Arabidopsis has five phytochromes, phyA-phyE, among which phyA and phyB play the most predominant functions . Light-regulated nuclear accumulation of the phytochromes is an important regulatory step of this pathway, but to this date no factor specifically required for this event has been identified . Among all phyA signaling mutants, fhy1 and fhy3 (far-red elongated hypocotyl 1 and 3) have the most severe hyposensitive phenotype, indicating that they play particularly important roles . FHY1 is a small plant-specific protein of unknown function localized both in the nucleus and the cytoplasm . Here we show that FHY1 is specifically required for the light-regulated nuclear accumulation of phyA but not phyB. Moreover, phyA accumulation is only slightly affected in fhy3, indicating that the diminished nuclear accumulation of phyA observed in fhy1 seedlings is not simply a general consequence of reduced phyA signaling. By in vitro pull-down and yeast two-hybrid analyses, we demonstrate that FHY1 physically interacts with phyA, preferentially in its active Pfr form. Furthermore, FHY1 and phyA colocalize in planta. We therefore identify the first component required for light-regulated phytochrome nuclear accumulation.

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The paper examines the relationship between family formation (i.e., living with a partner and having children) and women’s occupational career in southern Europe (i.e., Greece, Italy, Portugal and Spain). The relationship is explored by analysing the impact that different family structures and male [nvolvement in caring activities have on women’s early occupational trajectories (i.e., remaining in the same occupational status, experiencing downward or upward mobility, or withdrawing from paid work). This research shows that male involvement in caring activities does not really push women ahead in their career, but the absolute lack of male support seems to negatively affect women’s permanence in paid work. These results apply to all southern European countries except Portugal, where the absolute absence of the partners’ support in caring activities does not seem to alter women’s determination to remain in paid work. The methodology applied consists of the estimation of multinomial logit regression models and the analysis is based on eight waves (1994-2001) of the European Community Household Panel (ECHP).

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Objetivou-se analisar características sociodemográficas e clínicas de pessoas com úlceras vasculogênicas e investigar a associação entre estas variáveis. Realizou-se um estudo clínico observacional transversal, em salas de curativo de serviços municipais de saúde, de fevereiro a agosto de 2009. Realizou-se entrevista, exame clínico, aplicação da escala Pressure Ulcer Scale Healing (PUSH) e registro fotográfico das lesões. Participaram 42 indivíduos, com média de 60 anos (± 12), 73,8% do sexo masculino, com lesões únicas (66,7%), decorrentes de alteração da circulação venosa (90,5%), duração de até um ano (55,5%). Houve associação entre o escore da PUSH (p=0,019) e profundidade da lesão (p=0,027) com exercício de atividade ocupacional na atualidade, assim como entre o histórico de tabagismo e o gênero (p=0,049). As características sociodemográficas evidenciadas são semelhantes às de outros, com exceção do gênero masculino, o que indica a necessidade de maiores investigações na população goianiense.

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Tämä insinöörityö tehtiin ABB Oy, Drivesin Product AC -tulosyksikön tuotekehitysosastolle Helsingissä. Työssä kehitettiin taajuusmuuttajien suorituskyvyn automaattinen testausympäristö. ABB:n taajuusmuuttajien suorituskykytestejä ei ole aikaisemmin automatisoitu. Testit on tehty käsin ja niiden suorittamiseen ja tulosten käsittelyyn on kulunut paljon aikaa. Automaattisella testauksella pyrittiin testien suorittamiseen ja tulosten käsittelyyn kuluvan ajan huomattavaan pienentymiseen. Työssä ei ollut tarkoituksena tehdä suorituskykytestejä vaan kehittää automaattinen testausympäristö eli suorituskykytestipenkki, jossa suorituskykytestit on mahdollista suorittaa. Työssä keskityttiin taajuusmuuttajan nopeus- ja momenttisäätäjien suorituskykyyn. Työ toteutettiin suunnittelu- ja ohjelmointityönä. Testausympäristön laitteisto perustuu ABB:n tuotekehityslaboratorioiden olemassaoleviin testipaikkoihin. Testausympäristössä käytetään taajuusmuuttajien lisäksi pääasiassa kolmivaiheisia oikosulkumoottoreita. Lisäksi laitteistoon kuuluu ACS800-sarjan taajuusmuuttaja kuormakäyttönä, momenttianturi ja takometri eli kierrosnopeusmittari. Ohjelmointi tehtiin National Instrumentsin LabVIEW-ohjelmointiympäristön versiolla 8.0. Testausympäristön käyttöliittymänä toimii saman yrityksen TestStand-testausohjelmiston versio 3.5. Testattavien taajuusmuuttajien ohjausta ja momenttianturin lukemista varten ohjelmoitiin virtuaali-instrumentteja. Virtuaali-instrumentteja kutsutaan TestStand-testisekvensseistä. Testisekvenssit luodaan TestStandin sekvenssieditorilla ja suoritetaan sekvenssieditorissa tai operaattorin käyttöliittymässä. Työn tuloksena syntyi taajuusmuuttajien suorituskyvyn automaattinen testausympäristö. Testausympäristöä voidaan hyödyntää sekä nykyisen että seuraavan sukupolven taajuusmuuttajien testauksessa. Sillä on mahdollista suorittaa yleisimmät taajuusmuuttajien suorituskykytestit, kuten nopeus- ja momenttisäätöjen staattinen ja dynaaminen tarkkuus, hyvin kattavasti. Testit voidaan automaattisesti suorittaa koko testikäytön sallimalla pyörimisnopeus- ja kuormitusalueella. Näytteenottotaajuus voi olla enintään 1 kHz luettaessa pyörimisnopeutta ACS800-sarjan taajuusmuuttajan kautta ja momenttianturia samanaikaisesti. Virtuaali-instrumenteista koostuvia testisekvenssejä voidaan vapaasti muokata ja kehittää testejä edelleen tai luoda kokonaan uusia testejä. Testausympäristö perustuu teollisuudessa yleisesti käytettyihin ohjelmistoihin ja tarjoaa hyvät mahdollisuudet jatkokehitykselle.

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In Finland, European Union membership and economic globalisation have changed the position of regions from closed territorial systems to nodes of open international networks. The increasing complexity of cities as globalised knowledge centres and functionally specialised and diversified rural areas, and on the other hand growing disparities between prosperous urban cores and lagging peripheral areas are also essential features in contemporary regional development. These trends have produced new needs to promote mutual dialogue between cities and the countryside in western market economies. Urban-rural interaction is an idea which was developed in the late 1990s within regional policy to pull together these new challenges to regional development and handle cities and the countryside as a whole. The aim of my study is to conceptualise the idea of urban-rural interaction, explain the phenomenon theoretically, clarify past and present urban and rural development and analyse regional policies from the interaction angle. The ultimate purpose is to illustrate the existence and nature of particular interaction policy in a globalising society. The general method is discourse analysis, which I use in three cases: Central Finland, South-Ostrobothnia and South-West Finland. Theoretically I have a two-dimensional approach. On the first hand I use World-System theory to explain how the global economy is moulding urban and rural structures at the regional level. On the other hand I use regime theory to explain local political actions and practises between cities and the countryside under the overlapping pressures deriving from reformulated regional structures and policies.

Adaptation to globalisation in Finland has been carried out by strengthening urban centres. The stress in regional policy has been in urban development. The development of the countryside has mostly been implemented by a separate rural policy. At the end of the 1990s and early 2000s Finnish cities have actually shown themselves to be competitive in global markets. The drawbacks of the new growth centre policy have been the sparse network of prosperous cities and their weak spreading effects, which have hindered comprehensive regional development. Tensions between urban and rural areas have also deepened. In this situation the interaction policy is used as a way of balancing development and moderate conflicts within the regions. From this point of view urban-rural interaction can be seen as a way of tackling the challenges of globalisation.

On the other hand the results emphasise that actors involved in regional development still believe, although the hegemonic discourse is on urban policy, that there are opportunities to stimulate progress in the countryside as well. In the situation where regional authorities control development resources, rural development can be successful only if rural actors manage to establish fruitful relationships with their urban partners. This is also the weakness of the programme-based regional policy. If rural municipalities or other actors are for any reason incapable of building development regimes with cities, the offers of interaction policy will be useless.

The problem of the interaction policy is that the focus and methods of it have so far been rather underdeveloped. In order to improve the efficiency of the interaction policy, further research should concentrate on the social processes which define the position of cities and the countryside as partners of interaction, and practises which promote or prohibit the possibilities of developing the interaction policy. The efforts to define different contents of urban-rural interaction or promote interaction projects should not have such an important role in the future as they have had so far. Instead, the focus of interaction policy should be on questions such as how to manage the political tensions between town and country and how to create a positive atmosphere for regional policy where the needs of urban and rural development are promoted equally.

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Financial markets play an important role in an economy performing various functions like mobilizing and pooling savings, producing information about investment opportunities, screening and monitoring investments, implementation of corporate governance, diversification and management of risk. These functions influence saving rates, investment decisions, technological innovation and, therefore, have important implications for welfare. In my PhD dissertation I examine the interplay of financial and product markets by looking at different channels through which financial markets may influence an economy.My dissertation consists of four chapters. The first chapter is a co-authored work with Martin Strieborny, a PhD student from the University of Lausanne. The second chapter is a co-authored work with Melise Jaud, a PhD student from the Paris School of Economics. The third chapter is co-authored with both Melise Jaud and Martin Strieborny. The last chapter of my PhD dissertation is a single author paper.Chapter 1 of my PhD thesis analyzes the effect of financial development on growth of contract intensive industries. These industries intensively use intermediate inputs that neither can be sold on organized exchange, nor are reference-priced (Levchenko, 2007; Nunn, 2007). A typical example of a contract intensive industry would be an industry where an upstream supplier has to make investments in order to customize a product for needs of a downstream buyer. After the investment is made and the product is adjusted, the buyer may refuse to meet a commitment and trigger ex post renegotiation. Since the product is customized to the buyer's needs, the supplier cannot sell the product to a different buyer at the original price. This is referred in the literature as the holdup problem. As a consequence, the individually rational suppliers will underinvest into relationship-specific assets, hurting the downstream firms with negative consequences for aggregate growth. The standard way to mitigate the hold up problem is to write a binding contract and to rely on the legal enforcement by the state. However, even the most effective contract enforcement might fail to protect the supplier in tough times when the buyer lacks a reliable source of external financing. This suggests the potential role of financial intermediaries, banks in particular, in mitigating the incomplete contract problem. First, financial products like letters of credit and letters of guarantee can substantially decrease a risk and transaction costs of parties. Second, a bank loan can serve as a signal about a buyer's true financial situation, an upstream firm will be more willing undertake relationship-specific investment knowing that the business partner is creditworthy and will abstain from myopic behavior (Fama, 1985; von Thadden, 1995). Therefore, a well-developed financial (especially banking) system should disproportionately benefit contract intensive industries.The empirical test confirms this hypothesis. Indeed, contract intensive industries seem to grow faster in countries with a well developed financial system. Furthermore, this effect comes from a more developed banking sector rather than from a deeper stock market. These results are reaffirmed examining the effect of US bank deregulation on the growth of contract intensive industries in different states. Beyond an overall pro-growth effect, the bank deregulation seems to disproportionately benefit the industries requiring relationship-specific investments from their suppliers.Chapter 2 of my PhD focuses on the role of the financial sector in promoting exports of developing countries. In particular, it investigates how credit constraints affect the ability of firms operating in agri-food sectors of developing countries to keep exporting to foreign markets.Trade in high-value agri-food products from developing countries has expanded enormously over the last two decades offering opportunities for development. However, trade in agri-food is governed by a growing array of standards. Sanitary and Phytosanitary standards (SPS) and technical regulations impose additional sunk, fixed and operating costs along the firms' export life. Such costs may be detrimental to firms' survival, "pricing out" producers that cannot comply. The existence of these costs suggests a potential role of credit constraints in shaping the duration of trade relationships on foreign markets. A well-developed financial system provides the funds to exporters necessary to adjust production processes in order to meet quality and quantity requirements in foreign markets and to maintain long-standing trade relationships. The products with higher needs for financing should benefit the most from a well functioning financial system. This differential effect calls for a difference-in-difference approach initially proposed by Rajan and Zingales (1998). As a proxy for demand for financing of agri-food products, the sanitary risk index developed by Jaud et al. (2009) is used. The empirical literature on standards and norms show high costs of compliance, both variable and fixed, for high-value food products (Garcia-Martinez and Poole, 2004; Maskus et al., 2005). The sanitary risk index reflects the propensity of products to fail health and safety controls on the European Union (EU) market. Given the high costs of compliance, the sanitary risk index captures the demand for external financing to comply with such regulations.The prediction is empirically tested examining the export survival of different agri-food products from firms operating in Ghana, Mali, Malawi, Senegal and Tanzania. The results suggest that agri-food products that require more financing to keep up with food safety regulation of the destination market, indeed sustain longer in foreign market, when they are exported from countries with better developed financial markets.Chapter 3 analyzes the link between financial markets and efficiency of resource allocation in an economy. Producing and exporting products inconsistent with a country's factor endowments constitutes a serious misallocation of funds, which undermines competitiveness of the economy and inhibits its long term growth. In this chapter, inefficient exporting patterns are analyzed through the lens of the agency theories from the corporate finance literature. Managers may pursue projects with negative net present values because their perquisites or even their job might depend on them. Exporting activities are particularly prone to this problem. Business related to foreign markets involves both high levels of additional spending and strong incentives for managers to overinvest. Rational managers might have incentives to push for exports that use country's scarce factors which is suboptimal from a social point of view. Export subsidies might further skew the incentives towards inefficient exporting. Management can divert the export subsidies into investments promoting inefficient exporting.Corporate finance literature stresses the disciplining role of outside debt in counteracting the internal pressures to divert such "free cash flow" into unprofitable investments. Managers can lose both their reputation and the control of "their" firm if the unpaid external debt triggers a bankruptcy procedure. The threat of possible failure to satisfy debt service payments pushes the managers toward an efficient use of available resources (Jensen, 1986; Stulz, 1990; Hart and Moore, 1995). The main sources of debt financing in the most countries are banks. The disciplining role of banks might be especially important in the countries suffering from insufficient judicial quality. Banks, in pursuing their rights, rely on comparatively simple legal interventions that can be implemented even by mediocre courts. In addition to their disciplining role, banks can promote efficient exporting patterns in a more direct way by relaxing credit constraints of producers, through screening, identifying and investing in the most profitable investment projects. Therefore, a well-developed domestic financial system, and particular banking system, would help to push a country's exports towards products congruent with its comparative advantage.This prediction is tested looking at the survival of different product categories exported to US market. Products are identified according to the Euclidian distance between their revealed factor intensity and the country's factor endowments. The results suggest that products suffering from a comparative disadvantage (labour-intensive products from capital-abundant countries) survive less on the competitive US market. This pattern is stronger if the exporting country has a well-developed banking system. Thus, a strong banking sector promotes exports consistent with a country comparative advantage.Chapter 4 of my PhD thesis further examines the role of financial markets in fostering efficient resource allocation in an economy. In particular, the allocative efficiency hypothesis is investigated in the context of equity market liberalization.Many empirical studies document a positive and significant effect of financial liberalization on growth (Levchenko et al. 2009; Quinn and Toyoda 2009; Bekaert et al., 2005). However, the decrease in the cost of capital and the associated growth in investment appears rather modest in comparison to the large GDP growth effect (Bekaert and Harvey, 2005; Henry, 2000, 2003). Therefore, financial liberalization may have a positive impact on growth through its effect on the allocation of funds across firms and sectors.Free access to international capital markets allows the largest and most profitable domestic firms to borrow funds in foreign markets (Rajan and Zingales, 2003). As domestic banks loose some of their best clients, they reoptimize their lending practices seeking new clients among small and younger industrial firms. These firms are likely to be more risky than large and established companies. Screening of customers becomes prevalent as the return to screening rises. Banks, ceteris paribus, tend to focus on firms operating in comparative-advantage sectors because they are better risks. Firms in comparative-disadvantage sectors finding it harder to finance their entry into or survival in export markets either exit or refrain from entering export markets. On aggregate, one should therefore expect to see less entry, more exit, and shorter survival on export markets in those sectors after financial liberalization.The paper investigates the effect of financial liberalization on a country's export pattern by comparing the dynamics of entry and exit of different products in a country export portfolio before and after financial liberalization.The results suggest that products that lie far from the country's comparative advantage set tend to disappear relatively faster from the country's export portfolio following the liberalization of financial markets. In other words, financial liberalization tends to rebalance the composition of a country's export portfolio towards the products that intensively use the economy's abundant factors.

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A continental subduction-related and multistage exhumation process for the Tso Morari ultra-high pressure nappe is proposed. The model is constrained by published thermo-barometry and age data, combined with new geological and tectonic maps. Additionally, observations on the structural and metamorphic evolution of the Tso Morari area and the North Himalayan nappes are presented. The northern margin of the Indian continental crust was subducted to a depth of >90 km below Asia after continental collision some 55 Ma ago. The underthrusting was accompanied by the detachment and accretion of Late Proterozoic to Early Eocene sediments, creating the North Himalayan accretionary wedge, in front of the active Asian margin and the 103-50 Ma Ladakh arc batholith. The basic dikes in the Ordovician Tso Morari granite were transformed to eclogites with crystallization of coesite, some 53 Ma ago at a depth of >90 kin (>27 kbar) and temperatures of 500 to 600 degrees C. The detachment and extrusion of the low density Tso Morari nappe, composed of 70% of the Tso Morari granite and 30% of graywackes with some eclogitic dikes, occurred by ductile pure and simple shear deformation. It was pushed by buoyancy forces and by squeezing between the underthrusted Indian lithosphere and the Asian mantle wedge. The extruding Tso Morari nappe reached a depth of 35 km at the base of the North Himalayan accretionary wedge some 48 Ma ago. There the whole nappe stack recrystallized under amphibolite facies conditions of a Barrovian regional metamorphism with a metamorphic field gradient of 20 degrees C/km. An intense schistosity with a W-E oriented stretching lineation L, and top-to-the E shear criteria and crystallization of oriented sillimanite needles after kyanite, testify to the Tso Morari nappe extrusion and pressure drop. The whole nappe stack, comprising from the base to top the Tso Morari, Tetraogal, Karzok and Mata-Nyimaling-Tsarap nappes, was overprinted by new schistosities with a first N-directed and a second NE-directed stretching lineation L-2 and L-3 reaching the base of the North Himalayan accretionary wedge. They are characterized by top-to-the S and SW shear criteria. This structural overprint was related to an early N- and a younger NE-directed underthrusting of the Indian plate below Asia that was accompanied by anticlockwise rotation of India. The warping of the Tso Morari dome started already some 48 Ma ago with the formation of an extruding nappe at depth. The Tso Morari dome reached a depth of 15 km about 40 Ma ago in the eastern Kiagar La region and 30 Ma ago in the western Nuruchan region. The extrusion rate was of about 3 cm/yr between 53 and 48 Ma, followed by an uplift rate of 1.2 mm/yr between 48 and 30 Ma and of only 0.5 mm/yr after 30 Ma. Geomorphology observations show that the Tso Morari dome is still affected by faults, open regional dome, and basin and pull-apart structures, in a zone of active dextral transpression parallel to the Indus Suture zone.

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In addition to the ubiquitous apical-basal polarity, epithelial cells are often polarized within the plane of the tissue - the phenomenon known as planar cell polarity (PCP). In Drosophila, manifestations of PCP are visible in the eye, wing, and cuticle. Several components of the PCP signaling have been characterized in flies and vertebrates, including the heterotrimeric Go protein. However, Go signaling partners in PCP remain largely unknown. Using a genetic screen we uncover Kermit, previously implicated in G protein and PCP signaling, as a novel binding partner of Go. Through pull-down and genetic interaction studies, we find that Kermit interacts with Go and another PCP component Vang, known to undergo intracellular relocalization during PCP establishment. We further demonstrate that the activity of Kermit in PCP differentially relies on the motor proteins: the microtubule-based dynein and kinesin motors and the actin-based myosin VI. Our results place Kermit as a potential transducer of Go, linking Vang with motor proteins for its delivery to dedicated cellular compartments during PCP establishment.