Age-Dependent Acquisition of Protective Immunity to Malaria in Riverine Populations of the Amazon Basin of Brazil

Five community-based cross-sectional surveys of malaria morbidity and associated risk factors in remote riverine populations in northwestern Brazil showed average parasite rates of 4.2% (thick-smear microscopy) and 14.4% (polymerase chain reaction [PCR]) in the overall population, with a spleen rate of 13.9% among children 2-9 years of age. Plasmodium vivax was 2.8 times more prevalent than P. falciparum, with rare instances of P. malariae and mixed-species infections confirmed by PCR; 9.6% of asymptomatic subjects had parasitemias detected by PCR. Low-grade parasitemia detected by PCR only was a risk factor for anemia, after controlling for age and other covariates. Although clinical and subclinical infections occurred in all age groups, the risk of infection and disease decreased significantly with increasing age, after adjustment for several covariates in multilevel logistic regression models. These findings suggest that the continuous exposure to hypo- or mesoendemic malaria may induce significant anti-parasite and anti-disease immunity in native Amazonians.

Characterization of banana, sugarcane bagasse and sponge gourd fibers of Brazil

In recent times, increasing attention has been paid to the use of renewable resources particularly of plant origin keeping in view the ecological concerns, renewability and many governments passing laws for the use of such materials. On the other hand, despite abundant availability of lignocellulosic materials in Brazil, very few attempts have been made about their utilization, probably due to lack of sufficient structure/property data. Systematic studies to know their properties and morphology may bridge this gap while leading to value addition to these natural materials. Chemical composition, X-ray powder diffraction, and morphological studies and thermal behavior aspects in respect of banana, sugarcane bagasse sponge gourd fibers of Brazilian origin are presented. Chemical compositions of the three fibers are found to be different than those reported earlier. X-ray diffraction patterns of these three fibers exhibit mainly cellulose type I structure with the crystallinity indices of 39%, 48% and 50% respectively for these fibers. Morphological studies of the fibers revealed different sizes and arrangement of cells. Thermal stability of all the fibers is found to be around 200 degrees C. Decomposition of both cellulose and hemicelluloses in the fibers takes place at 300 degrees C and above, while the degradation of fibers takes place above 400 degrees C. These data may help finding new uses for these fibers. (C) 2009 Elsevier B.V. All rights reserved.

The trasition from fixed to floating exchange rate regimes: the case of Brazil

This dissertation evaluates macroeconomic management in Brazil from 1994 to the present, with particular focus on exchange rate policy. It points out that while Brazil's Real Plan succeeded in halting the hyperinflation that had reached more than 2000 percent in 1993, it also caused significant real appreciation of the exchange rate situation that was only made worse by the extremely high interest rates and ensuing bout of severe financial crises in the intemational arena. By the end of 1998, the accumulation of internai and externai imbalances led the authorities to drop foreign exchange controls and allow the currency to float. In spite of some initial scepticism, the flexible rate regime cum inflation target proved to work well. Inflation was kept under control; the current account position improved significantly, real interest rates fell and GDP growth resumed. Thus, while great challenges still lie ahead, the recent successes bestow some optimism on the well functioning of this exchange rate regime. The Brazilian case suggests that successful transition from one foreign exchange system to another, particularly during financial crisis, does not depend only on one variable be it fiscal or monetary. In reality, it depends on whole set of co-ordinated policies aimed at resuming price stability with as little exchange rate and output volatility as possible.

Public debt indexation and denomination, the case of Brazil: a comment

In this work I analyze the model proposed by Goldfajn (2000) to study the choice of the denomination of the public debt. The main purpose of the analysis is pointing out possible reasons why new empirical evidence provided by Bevilaqua, Garcia and Nechio (2004), regarding a more recent time period, Önds a lower empirical support to the model. I also provide a measure of the overestimation of the welfare gains of hedging the debt led by the simpliÖed time frame of the model. Assuming a time-preference parameter of 0.9, for instance, welfare gains associated with a hedge to the debt that reduces to a half a once-for-all 20%-of-GDP shock to government spending run around 1.43% of GDP under the no-tax-smoothing structure of the model. Under a Ramsey allocation, though, welfare gains amount to just around 0.05% of GDP.

What happens after the central bank of Brazil increases the target interbank rate by 1%?

I start presenting an explicit solution to Taylorís (2001) model, in order to illustrate the link between the target interest rate and the overnight interest rate prevailing in the economy. Next, I use Vector Auto Regressions to shed some light on the evolution of key macroeconomic variables after the Central Bank of Brazil increases the target interest rate by 1%. Point estimates show a four-year accumulated output loss ranging from 0:04% (whole sample, 1980 : 1-2004 : 2; quarterly data) to 0:25% (Post-Real data only) with a Örst-year peak output response between 0:04% and 1:0%; respectively. Prices decline between 2% and 4% in a 4-year horizon. The accumulated output response is found to be between 3:5 and 6 times higher after the Real Plan than when the whole sample is considered. The 95% confidence bands obtained using bias-corrected bootstrap always include the null output response when the whole sample is used, but not when the data is restricted to the Post-Real period. Innovations to interest rates explain between 4:9% (whole sample) and 9:2% (post-Real sample) of the forecast error of GDP.

A brief history of Brazil's growth

The paper studies Brazil’s economic growth and begins with a brief overview of events that marked the country’s development from her discovery to the 19th century. It then divides the years between 1900 and 2008 into four periods. The breaks in regime occur in 1918, 1967 and 1980, according to the methodology created by Bai and Perron (1998, 2003). The use of the accounting methodology serves the analysis of the behavior of productivity in the previously identified different phases of the post-World War II period. High inflation might have been a reason for the decline in productivity observed between 1980 and mid-1990s. The paper shows that terms of trade have a significant effect on economic growth and output fluctuations. Other factors (such as fiscal stimulus or easy access to foreign finance) also matter for output accelerations in the short run. From 2004 to 2008, terms of trade improvement and debt reduction brought economic progress. The emergence of a new era in this millennium will depend on wiser fiscal policies than those of the past.

What happens after the Central Bank of Brazil increases the target interbank rate by 1%?

In this paper I use Taylor's (2001) model and Vector Auto Regressions to shed some light on the evolution of some key macroeconomic variables after the Central Bank of Brazil, through the COPOM, increases the target interest rate by 1%. From a quantitative perspective, the best estimate from the empírical analysis, obtained with a 1994 : 2 - 2004 : 2 subsample of the data, is that GDP goes through an accumulated decline, over the next four years, around 0.08%. Innovations to interest rates explain around 9.2% of the forecast erro r of GDP.

Comments on public debt indexation and denomination, the case of Brazil

In this work I analyze the model proposed by Goldfajn (2000) to study the choice of the denomination of the public debt. Some potential shortcmomings of the mo dei in explaining the data are discussed. Measures of the overestimation of the welfare gains of reducing distortions from taxation, under the model's simplified time frame, are also provided. Assuming a time-preference parameter of 0.9, for instance, welfare gains associated with a hedge to the debt that reduces to half a once-for-all 20o/o-of-GDP shock to governemnt spending run around 1.43% of GDP under the no-tax-smoothing structure of the model. Under a Ramsey allocation, though, welfare gains amount to just around 0.05% of GDP.

Temporal causality between the exchange rate and the trade balance : the case of Brazil

The paper assesses the impact of intemational relative prices and domestic expenditure variables on Brazil' s foreign trade performance in the first half of the 1990s. It has been argued that the appreciation of the Real since 1994 has had a detrimental impact of the country's trade balance. However, using temporal precedence analysis, our results do not indicate that the trade balance is strongly affected by intemational rei ative prices, such as the exchange rate. Instead, domestic expenditure variables appear to be more powerful determinant of the country' s trade performance in recent years. Granger and error correction causality techniques are used to determine temporal precedence between the trade balance and the exchange rate in the period under examination. Our findings shed light on the debate over the sustainability of recent exchange rate-anchored macroeconomic stabilisation programmes, which is a topic that has encouraged a lot of debate among academics and practitioners.

Immigration as a strategic vector for the socio-economic and institutional development of Brazil

Brazil has demonstrated resilience in relation to the recent economic crises and has an auspicious development potential projected for the coming decades, which, linked to the globalization process, provides important opportunities for our people. Gradually we have established ourselves as one of the leading nations in the world and we have become a reference in questions linked to economic equilibrium, development, energy, agriculture and the environment. This international recognition favors the exchange of experiences with other cultures, governments and organizations, bringing with it the possibility of stimulating a dynamic process of development and innovation.