Silicate content in sediment ofthe Santa Monica Basin, California

Seafloor recycling of organic materials in Santa Monica Basin, California was examined through in situ benthic chamber experiments, shipboard whole-core incubations and pore water studies. Mass balance calculations indicate that the data are internally consistent and that the estimated benthic exchange rates compare well with those derived from deep, moored conical sediment traps and hydrographic modeling. Pore water and benthic flux observations indicate that the metabolizable organic matter at the seafloor must be composed of at least two fractions of very different reactivities. While the majority of reactive organic compounds degrade quickly, with a half-life of <=6.5 years, 1/4 of the total metabolizable organic matter appears to react more slowly, with a half-life on the order of 1700 years. Down-core changes in pore water sulfate and titration alkalinity are not explained by stoichiometric models of organic matter diagenesis and suggest that reactions not considered previously must be influencing the pore water concentrations. Measured recycling and burial rates indicate that 43% of the organic carbon reaching the basin seafloor is permanently buried. The results for Santa Monica Basin are compared to those reported for other California Borderland Basins that differ in sedimentation rate and bottom water oxygen content. Organic carbon burial rates for the Borderland Basins are strongly correlated with total organic carbon deposition rate and bulk sedimentation rate. No significant correlation is observed between carbon burial and bottom water oxygen, extent of oxic mineralization and sediment mixing. Thus, for the California Borderlands, it appears that carbon burial rates are primarily controlled by input rates and not by variations in preservation.

Stable isotope composition of Holocene benthic foraminifers from the Eastern Mediterranean Sea

Temporal and regional changes in paleoproductivity and paleoceanography in the eastern Mediterranean Sea during the past 12 kyr were reconstructed on the basis of the stable oxygen and carbon isotope composition of the epibenthic Planulina ariminensis and the shallow endobenthic Uvigerina mediterranea from three sediment cores of the Aegean Sea and Levantine Basin. The Younger Dryas is characterized by high d18O values, indicating enhanced salinities and low temperatures of deep water masses at all investigated sites. With the onset of the Holocene, d18O records show a continuous decrease towards the onset of sapropel S1 formation, mainly caused by a freshening and warming of surface waters at deep water formation sites. In the middle and late Holocene, the similarity of d18O values from the southern Aegean Sea and Levantine Basin suggests the influence of isotopically identical deep water masses. By contrast, slightly higher d18O values are observed the northern Aegean Sea, which probably point to lower temperatures of North Aegean deep waters. The epifaunal d13C records reveal clear changes in sources and residence times of eastern Mediterranean deep waters associated with period of S1 formation. Available data for the early and late phase of sapropel S1 formation and for the interruption around 8.2 kyr display drops by 0.5 and 1.5 per mil, indicating the slow-down of deep water circulation and enhanced riverine input of isotopically light dissolved inorganic carbon from terrestrial sources into the eastern Mediterranean Sea. The decrease in epifaunal d13C signals is particularly expressed in the southern Aegean Sea and Levantine Basin, while it is less pronounced in the northern Aegean Sea. This points to a strong reduction in deep water exchange rates in the southern areas, but the persistence of local deep water formation in the northern Aegean Sea. The d13C values of U. mediterranea records reveal temporal and regional differences in paleoproductivity during the past 12 kyr, with rather eutrophic and mesotrophic conditions in the North Aegean Sea and southeast Levantine Basin, respectively, while the South Aegean Sea is characterized by rather oligotrophic conditions. After S1 formation, increasing d13C values reflect a progressive decrease in surface water productivity in the eastern Mediterranean Sea during the middle and late Holocene. In the northern Aegean Sea, this time interval is marked by repetitive changes in organic matter fluxes documented by significant fluctuations in the d13C signal of U. mediterranea on millennial- to multi-centennial time scales. These fluctuations can be linked to short-term changes in river runoff driven by northern hemisphere climatic variability.

International Competitiveness of Manufacturing Firms in sub-Saharan Africa

As the success of East Asian countries has shown, labor-intensive industry is recognized to lead economic growth in the early stages of development, utilizing relatively low labor costs. This same growth process has already started in South and South East Asian LDCs since the mid-1990s. However, the manufacturing sector in sub-Saharan Africa has been underdeveloped and manufacturing exports, in particular labour-intensive goods, have stagnated. This paper investigates the international competitiveness of the African manufacturing sector and its determinants through an analytical survey of empirical studies and a comparison with Asian low income countries. Empirical evidences indicate that primary factors of competitiveness, namely productivity, labour cost and exchange rate are unfavorable in sub-Saharan Africa. Representative arguments attribute the weak competitiveness to problems in the business environment, factor endowment, and the exchange rate. However, careful review shows that labour cost is beyond the range explained by endowment and misalignment of exchange rates have been reduced in Africa. Moreover, comparison with Asian low income countries which have competitiveness in labour-intensive goods shows no difference in the quality of business environment, while the labour cost is significantly lower than sub-Saharan African countries. Although results should be considered tentative, high labour cost beyond endowment and conservative investment behavior emerge as important factors for the weak competitiveness in sub-Saharan Africa when controlling income level.

Monetary Systems in Developing Countries: An Unorthodox View

This paper analyzes some recent theoretical and practical evidence in terms of economic results of different exchange rate systems. It begins with a historical review and a summary of fixed versus flexible exchange rate systems. Then it compares the experiences of recent currency unions, mostly unilateral, and their relative economic performance during the past currency crises in Latin America, East Asia and Eastern Europe. A set of issues is discussed in order to weigh the overall costs and benefits for several economies. These issues include exchange rates, GDP performance, inflation rates and foreign reserves. The case of Argentina is also considered separately, comparing mostly seigniorage costs and interest-rate savings. The benefits and costs of the producers (central banks/governments) and the consumers (citizens) of money are discussed separately. Free banking is also considered in a fast-changing world where there will probably be fewer but better currencies. Not just the euro is a reality now, but maybe the "amero" and the "worldo" or the "mondo" very soon.

Financial Policies and Dynamic Game Simulation in Poland and Hungary

Recently, steady economic growth rates have been kept in Poland and Hungary. Money supplies are growing rather rapidly in these economies. In large, exchange rates have trends of depreciation. Then, exports and prices show the steady growth rates. It can be thought that per capita GDPs are in the same level and development stages are similar in these two countries. It is assumed that these two economies have the same export market and export goods are competing in it. If one country has an expansion of monetary policy, price increase and interest rate decrease. Then, exchange rate decrease. Exports and GDP will increase through this phenomenon. At the same time, this expanded monetary policy affects another country through the trade. This mutual relationship between two countries can be expressed by the Nash-equilibrium in the Game theory. In this paper, macro-econometric models of Polish and Hungarian economies are built and the Nash- equilibrium is introduced into them.

Real Options: A Tool for Managing Technical Risk in a Mine Plan

NPV is a static measure of project value which does not discriminate between levels of internal and external risk in project valuation. Due to current investment project?s characteristics, a much more complex model is needed: one that includes the value of flexibility and the different risk levels associated with variables subject to uncertainty (price, costs, exchange rates, grade and tonnage of the deposits, cut off grade, among many others). Few of these variables present any correlation or can be treated uniformly. In this context, Real Option Valuation (ROV) arose more than a decade ago, as a mainly theoretical model with the potential for simultaneous calculation of the risk associated with such variables. This paper reviews the literature regarding the application of Real Options Valuation in mining, noting the prior focus on external risks, and presents a case study where ROV is applied to quantify risk associated to mine planning.

UMA ANÁLISE DA RELAÇÃO ENTRE VARIÁVEIS MACROECONÔMICAS E O COMPORTAMENTO DAS AÇÕES DE MAIOR LIQUIDEZ DO ÍNDICE IBOVESPA

As ações de maior liquidez do índice IBOVESPA, refletem o comportamento das ações de um modo geral, bem como a relação das variáveis macroeconômicas em seu comportamento e estão entre as mais negociadas no mercado de capitais brasileiro. Desta forma, pode-se entender que há reflexos de fatores que impactam as empresas de maior liquidez que definem o comportamento das variáveis macroeconômicas e que o inverso também é uma verdade, oscilações nos fatores macroeconômicos também afetam as ações de maior liquidez, como IPCA, PIB, SELIC e Taxa de Câmbio. O estudo propõe uma análise da relação existente entre variáveis macroeconômicas e o comportamento das ações de maior liquidez do índice IBOVESPA, corroborando com estudos que buscam entender a influência de fatores macroeconômicos sobre o preço de ações e contribuindo empiricamente com a formação de portfólios de investimento. O trabalho abrangeu o período de 2008 a 2014. Os resultados concluíram que a formação de carteiras, visando a proteção do capital investido, deve conter ativos com correlação negativa em relação às variáveis estudadas, o que torna possível a composição de uma carteira com risco reduzido.

ANALISANDO A RELAÇÃO DOS VOLUMES DE EXPORTAÇÃO E DE IMPORTAÇÃO, PIB, TAXAS DE CÂMBIO E INFLAÇÃO NO PERÍODO DE 2004 A 2014.

Esta dissertação visa deslumbrar uma análise macroeconômica do Brasil, especialmente no que se refere à relação dos índices mensais dos volumes das exportações e das importações com os volumes mensais do PIB, da Taxa SELIC e as Taxas de Câmbio, conforme dados coletados no período de janeiro de 2004 a dezembro de 2014, através de pesquisa literária referente aos históricos sobre cada conceito envolvido no âmbito da macroeconomia das varáveis estudadas. Foi realizado um estudo de caso embasado em dados de sites governamentais, no período delimitado, empregando-se o método de regressão linear, com base na Teoria da correlação de Pearson, demonstrando os resultados obtidos no período do estudo para as varáveis estudadas. Desta maneira, conseguiu-se estudar e analisar como as variáveis dependentes (resposta): volume das exportações e volume das importações estão relacionadas com as varáveis independentes (explicativas): PIB, Taxa Selic e taxa de Câmbio. Os resultados apurados no presente estudo permitem identificar que existe correlação moderada e negativa, quando analisadas a Taxa Selic e a Taxa de Câmbio com os volumes das exportações e das importações, enquanto o PIB apresenta correlação forte e positiva na análise com os volumes das exportações e das importações

A signature of the T → R transition in human hemoglobin

Allosteric effects in hemoglobin arise from the equilibrium between at least two energetic states of the molecule: a tense state, T, and a relaxed state, R. The two states differ from each other in the number and energy of the interactions between hemoglobin subunits. In the T state, constraints between subunits oppose the structural changes resulting from ligand binding. In the R state, these constraints are released, thus enhancing ligand-binding affinity. In the present work, we report the presence of four sites in hemoglobin that are structurally stabilized in the R relative to the T state. These sites are Hisα103(G10) and Hisα122(H5) in each α subunit of hemoglobin. They are located at the α1β1 and α2β2 interfaces of the hemoglobin tetramer, where the histidine side chains form hydrogen bonds with specific residues from the β chains. We have measured the solvent exchange rates of side chain protons of Hisα103(G10) and Hisα122(H5) in both deoxygenated and ligated hemoglobin by NMR spectroscopy. The exchange rates were found to be higher in the deoxygenated-T than in ligated-R state. Analysis of exchange rates in terms of the local unfolding model revealed that the structural stabilization free energy at each of these two histidines is larger by ≈1.5 kcal/(mol tetramer) in the R relative to the T state. The location of these histidines at the intradimeric α1β1 and α2β2 interfaces also suggests a role for these interfaces in the allosteric equilibrium of hemoglobin.

Role of hydrophobic interactions and desolvation in determining the structural properties of a model alpha beta peptide.

Model AB, a 20-amino acid peptide that was designed to adopt an alpha beta tertiary structure stabilized by hydrophobic interactions between residues in adjacent helical and extended segments, exhibited large pKa shifts of several ionizable groups and slow hydrogen/deuterium exchange rates of nearly all the peptide amide groups [Butcher, D. J., Bruch, M. D. & Moe, G. T. (1995) Biopolymers 36, 109-120]. These properties, which depend on structure and hydration, are commonly observed in larger proteins but are quite unusual for small peptides. To identify which of several possible features of the peptide design are most important in determining these properties, several closely related analogs of Model AB were characterized by CD and NMR spectroscopy. The results show that hydrophobic interactions between adjacent helical and extended segments are structure-determining and have the additional effect of altering water-peptide interactions over much of the peptide surface. These results may have important implications for understanding mechanisms of protein folding and for the design of independently folding peptides.

Sovereign debt and its restructuring framework in the Euro area. Bruegel Working Paper 2013/05, August 2013

To compensate for the inflexibility of fixed exchange rates, the euro area needs flexibility through a system of orderly debt restructuring. With virtually no room for macroeconomic manoeuvring since the crisis onset, fiscal austerity has been the main instrument for achieving reductions in public debt levels; but because austerity also weakens growth, public debt ratios have barely budged. Austerity has also implied continued high private debt ratios. And these debt burdens have perpetuated economic stasis. Economic theory,history, and the recent experience all call for a principled debt restructuring mechanism as an integral element of the euro area’s design. Sovereign debt should be recognised as equity (a residual claim on the sovereign), operationalised by the automatic lowering of the debt burden upon the breach of contractually-specified thresholds. Making debt more equity-like is also the way forward for speedy private deleveraging. This debt-equity swap principle is a needed shock absorber for the future but will also serve as the principle to deal with the overhang of ‘legacy’ debt.

The Ghost of Deflation Past. CEPS Hi-level Brief, 13 December 2013

This note takes a look at the development of monetary aggregates and debt in the G7 (US, UK, France, Germany, Italy, Canada and Japan), plus non-G7 euro-area countries, which have an important bearing on the future development of price levels. It also discusses the problem of restoring external competitiveness in the weaker euro-area countries without aggravating their debt burden. The key conclusions are i) monetary and debt developments in the G7 countries point to relatively sluggish growth but do not signal deflation risks and ii) the realignment of ‘internal real exchange rates’ in the euro area will most likely come through a rise in prices in Germany (and a few other stronger countries). The lessons learned in the early 1930s have made a come-back of deflation quite unlikely.

Le role des politiques monétaires et la convergence macroeconomique sur le développement des systèmes financiers dans les pays du sud de la Méditerranée. = The role of monetary policies and macroeconomic convergence in the development of financial systems in south Mediterranean countries. MEDPRO Technical Report No. 12/April 2012

This MEDPRO Technical Report shows that the monetary and exchange rate policies conducted by central banks in the South Mediterranean region display apparent homogeneity in their operational frameworks, albeit with some specificities and differing degrees of advancement. While central banks state that price stability is their ultimate objective, failures to control interest rates as operational objectives of monetary policy result in monetary authorities resorting to quantitative approaches to monetary policy, meaning that monetary aggregates and credit targets are being used as intermediate targets of monetary policy. An econometric exercise limited to Maghreb countries (Algeria, Morocco, and Tunisia) has been conducted to analyse the potential scenarios of convergence and monetary policy coordination. Given the high structural heterogeneity and the slow pace of real convergence due to weak commercial integration in the Maghreb, results nevertheless show alternative dynamics in the integration of effective nominal exchange rates, as well as a complete convergence dynamic in exchange rate policies. Partial convergence of monetary policies regarding the stabilisation of inflation rates remains an open option for a transitional phase where financial integration is low.

Europe on the Road to the Third Stage of EMU: Recent Evidence. CES Germany & Europe Working Papers, No. 07.2, 1996

The paper deals with Europe's effort to proceed to the thud stage of EMU and establish a common currency. It is argued that the success of the common currency experiment will greatly depend on the fulfillment of the Optimum Currency Area (OCA) criteria, on the adoption of the proper adjustment policies as well as on the political desirability of the project. The paper is organized as follows: Section 1 deals briefly with the index of criteria that define an OCA. Section 2 examines the extent to which Europe experiences common demand disturbances, while sections 3 and 4 focus on evidence about the mobility of factors of production across Europe, namely labor and capital. Section 5 examines the possibility of an increase in trade volume across the EU under fixed exchange rates or a common currency regime. Section 6 sheds light on the possibility of the EURO (the ex-ECU} to become a vehicle currency in the international financial system, and Section 7 is concerned with the benefits and costs of the establishment of a European Central Bank (ECB), paying special attention to seigniorage revenues. Section 8 deals with the necessity of establishing an EU federal mechanism facilitating adjustment. Section 9 sketches out a proper role for a hegemonic power in a common currency regime. Finally, section 10 examines EMU prospects during the transitional period. The paper closes with some concluding remarks, where the role of politics and coordination of economic policies are particularly emphasized as of cardinal importance on the road to the third stage of EMU.