Trade agreements and bilateral trade in sub-Saharan Africa: Estimating the trade effects of the EU-ACP PTA and RTAs

This paper on Trade Agreements within SSA, is an assessment of the ex post bilateral trade effect of the European Union-African Caribbean Pacific Preferential Trade Agreement (EU-ACP PTA) and sub-regional regional trade agreements (RTAs) on bilateral trade involving SSA countries. The main objective is to find out if EU trade preferences and regional trade agreements within SSA had increased trade flows. Estimating a gravity model augmented with measures of trade agreements, the paper made use of bilateral trade flows and key gravity covariates from CEPII database on 73 countries (48 SSA and 25 EU countries) over the period 1960-2006. After controlling for the endogeneity of the trade agreement dummy, accounting for multilateral price resistance and zero-valued trade flows, the findings indicate that the EU-ACP PTA and RTAs within ECOWAS and SADC have a positive and significant impact on bilateral trade involving SSA countries. In some cases the relative impact of the sub-regional RTAs was found to be stronger than the EU-ACP non-reciprocal PTA. The results therefore indicate the need for developing countries especially within SSA to focus on expanding and integrating regional markets in order to significantly improve trade performance

Using observable trade data to measure bilateral trade costs in sub-Saharan Africa

Following closely the analytical approach adopted by Head and Mayer (2004) and Novy (2010), this paper derives a micro-founded bilateral trade cost measure for sub-Saharan Africa (SSA) as a function of observable domestic and inter-national trade data. The derived measure of trade cost by Novy (2010), consistent with the Ricardian and heterogeneous firm's models of trade, enables us to track changes in trade costs in SSA over time. This is a significant contribution to the trade cost literature in SSA because measures of many components of trade frictions in SSA have been unreliable. Based on bilateral trade data from BACI and production figures from the Trade, Production and Protection database by Nicita and Olarreaga (2007) for the period 1980-2003, our estimates of the tariff equivalent bilateral trade costs measure indicate that on average trade costs in SSA are relatively higher than other regions, confirming evidence which indicates trading costs in SSA to be the highest within the global trading system. The estimates indicate that SSA countries traded with each other at a lower cost than they did with other regions with the exception of the EU. Within SSA, member countries of economic blocs traded at relatively lower costs than trade with non-member countries. Using each of the main five economic blocs within SSA as a reference, overall average relative bilateral trade costs within bloc was significantly lower than across blocs. This paper therefore argues for increased efforts at regional integration within SSA to derive benefits from lower trade costs

Scoping study on the evolution of industry in Ghana

This paper chronicles the evolution of industry in Ghana over the post-independence era from an inward over-protected import substitution industrialization strategy of 1960-83 to an outward liberalized strategy during 1984-2000, and since 2001, to the private sector-led accelerated industrial development strategy based on value-added processing of Ghana's natural resource endowments. Over the last couple of years, industry in Ghana, dominated since independence by the manufacturing subsector, is gradually being overtaken by mining and quarrying subsector due to the discovery and subsequent production of oil and gas. Industry is mainly dominated by micro and small firms, privately-owned and mainly located within urban areas in the form of industrial clusters. Patterns of labour productivity and wages within Ghana's industrial sector indicate the food processing subsector, foreign-owned and older firms as the most productive. Currently under a medium-term agenda, the industrial sector is expected to play a pivotal role through enhanced growth in the construction sector; infrastructure development in the oil sector, energy and water subsectors and an increase in output from the mining sector, especially in salt production. The emerging policy issues relate to the key developmental objectives of the current industrial policy including how to empower the private sector especially SMEs to expand productive employment and technological capacity within a highly competitive manufacturing sector; how to promote agro-based industrial development to ensure value-addition to manufactures and Ghana's exports; and how to promote the spatial distribution of industries away from the current over-concentration of industries within urban areas

Foreign direct investment spillovers and the Ghanaian local financial environment

Using the bound cointegration test, we examine how Foreign Direct Investment (FDI) influences Ghana’s growth through the financial environment. We use data from different sources including the World Development Indicators (WDI) of the World Bank, covering the period 1977-2010 to address this. Our key results are interesting. Specifically, our results show that, both in the short run and in the long run, FDI will have a better influence on growth in a sound financial environment. However, whiles the capital market is important to propel FDI’s influence on Ghana’s growth in the long-run; in the short run, developing the banking sector alone is not sufficient to achieve growth. Banking sector development needs FDI to influence growth. Our results justify enormous efforts made by Ghana to attract FDI and further suggest that the continuation of this policy will be beneficial to the economy given the relative progress made with regards to banking system and capital market development over the past two decades

Education, skill, and earnings: Further evidence from Ghana

This paper provides evidence on the nature of returns to education in Ghana and confirms the emerging empirical literature on the convexity of returns to education in Ghana. Using a basic Mincerian, model we find that returns to education more than triples from primary to secondary level or higher - an indication of a rather strong convex relationship. The results point to the importance of higher education in productivity. Nonetheless educational policies should not only be directed at increasing enrolment and quality of education at the secondary and higher educational levels but also at improving the quality of basic education

Supply modulator for linear wideband RF power amplifiers

Este artículo trata de las técnicas de diseño de reguladores de potencia conmutados de alta eficiencia destinados a alimentar amplificadores de potencia (PAs) lineales, empleando técnicas de seguimiento para estándares inalámbricos de banda ancha. Los cuellos de botella presentados implican un compromiso entre tensión, slew rate y ancho de banda. De hecho, la limitación de slew rate es identificada como el principal desafío. Por tanto, se propone una técnica de mejora del slew rate denominada “bang-bang”. Este enfoque permite el uso de moduladores de alimentación eficientes para la alimentación de los mencionado amplificadores de potencia de banda ancha. El esquema propuesto no degrada significativamente la eficiencia del PA y preserva, e incluso mejora, la estabilidad del regulador conmutado. El prototipo ha sido implementada utilizando la tecnología de TSMC 0,18 μm. Resultados de simulación post-layout en Cadence® son presentados para demostrar la viabilidad del diseño llevado a cabo.This paper deals with the design techniques of power efficient switching regulators intended for linear power amplifiers (PAs) employing envelope tracking techniques in wideband wireless standards. The bottlenecks involve a tradeoff between ripple voltage, slew rate and bandwidth. The slew rate limitation is identified as the main challenge; thus a ‘bang-bang’ slew-enhancement technique is proposed. This approach enables the use of efficient supply modulators in wideband power amplifiers. The proposed scheme does not significantly degrade PA efficiency and preserves, and even improves, the stability of the switching regulator. The prototype has been implemented using the TSMC 0.18 μm technology; schematic simulation results in Cadence® are presented to prove the concept.Peer Reviewe

Signal transducer and activator of transcription-1 localizes to the mitochondria and modulates mitophagy

The signal transducer and activator of transcription (STAT) proteins are latent transcription factors that have been shown to be involved in cell proliferation, development, apoptosis, and autophagy. STAT proteins undergo activation by phosphorylation at tyrosine 701 and serine 727 where they translocate to the nucleus to regulate gene expression. STAT1 has been shown to be involved in promoting apoptotic cell death in response to cardiac ischemia/reperfusion and has recently been shown by our laboratory to be involved in negatively regulating autophagy. These processes are thought to promote cell death and restrict cell survival leading to the generation of an infarct. Here we present data that shows STAT1 localizes to the mitochondria and co-immunoprecipitates with LC3. Furthermore, electron microscopy studies also reveal mitochondria from ex vivo I/R treated hearts of STAT1KO mice contained within a double membrane autophagosome indicating that STAT1 may be involved in negatively regulating mitophagy. This is the first description of STAT1 being localized to the mitochondria and also having a role in mitophagy

Erythropoietin-induced serine 727 phosphorylation of STAT3 in erythroid cells is mediated by a MEK-, ERK-, and MSK1-dependent pathway

Objective. Erythropoietin (EPO) is a key regulator of erythropoiesis, playing a role in both the proliferation and differentiation of erythroid cells. One of the signal transduction molecules activated upon EPO stimulation is signal transducer and activator of transcription (STAT) 3. Besides tyrosine 705 phosphorylation of STAT3, serine 727 phosphorylation has been described upon EPO stimulation. In the present study, we investigated which molecular pathways mediate the STAT3 serine 727 phosphorylation and the functional implications of this phosphorylation. Methods. The EPO-dependent erythroid cell line ASE2 was used to investigate which signaling routes were involved in the STAT3 serine 727 phosphorylation. Western blotting using phosphospecific antibodies was used to assess the phosphorylation status of STAT3 molecules. Transfection analysis was performed to investigate the transactivational potential of STAT3, and quantitative RT-PCR was used to study the in vivo gene expression of STAT3-responsive genes. Results. Western blotting of extracts of cells exposed to various chemical inhibitors revealed that the MEK inhibitors PD98059 and U0126 abrogated the EPO-mediated STAT3 serine 727 phosphorylation without an effect on tyrosine phosphorylation. Further analysis showed that MSK1 is activated downstream of ERK, and retroviral transductions with kinase-inactive MSK1 revealed that MSK1 is necessary for STAT3 serine phosphorylation. Furthermore, the STAT3-mediated transactivation was reduced by blocking the STAT3 serine phosphorylation with the MEK inhibitor U0126 or by expression of kinase-inactive MSK1. Conclusions. The EPO-induced STAT3 serine 727 phosphorylation is mediated by a pathway involving MEK, ERK, and MSK1. Furthermore, serine phosphorylation of STAT3 augments the transactivational potential of STAT3.