Can the distributional impacts of macroeconomic shocks be predicted? A comparison of the performance of macro-micro models with historical data for Brazil

What was the impact of Brazil's 1998-99 currency crisis-which resulted in a change of exchange rate regime and a large real devaluation-on the occupational structure of the labor force and the distribution of incomes? Would it have been possible to predict such effects ahead of the crisis? The authors present an integrated macro-micro model of the Brazilian economy in 1998. The model consists of an applied general equilibrium macroeconometric component, connected through a set of linkage aggregate variables to a microeconomic model of household incomes. The authors use this framework to predict the employment and distributional consequences of the 1999 Brazilian currency crisis, based on 1998 household survey data. They then test the predictive performance of the model by comparing its simulated results with the actual household survey data observed in 1999. In addition to the fully integrated macro-micro model, the authors also test the performances of the microeconometric model on its own, and of a"representative household groups"approach. They find that the integrated macro-micro econometric model, while still inaccurate on many dimensions, can actually predict the broad pattern of the incidence of changes in household incomes across the distribution reasonably well, and much better than the alternative approaches. The authors conclude that further experimentation with these tools might be of considerable potential usefulness to policymakers.Labor Policies,Payment Systems&Infrastructure,Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Economic Theory&Research,Environmental Economics&Policies,Macroeconomic Management,Inequality,Economic Stabilization

Disorder and the effective Mn-Mn exchange interaction in Ga1−x_{1-x}Mnx_xAs diluted magnetic semiconductors

We perform a theoretical study, using {\it ab initio} total energy density-functional calculations, of the effects of disorder on the $Mn-Mn$ exchange interactions for $Ga_{1-x}Mn_xAs$ diluted semiconductors. For a 128 atoms supercell, we consider a variety of configurations with 2, 3 and 4 Mn atoms, which correspond to concentrations of 3.1%, 4.7%, and 6.3%, respectively. In this way, the disorder is intrinsically considered in the calculations. Using a Heisenberg Hamiltonian to map the magnetic excitations, and {\it ab initio} total energy calculations, we obtain the effective \JMn, from first ($n=1$) all the way up to sixth ($n=6$) neighbors. Calculated results show a clear dependence in the magnitudes of the \JMn with the Mn concentration $x$. Also, configurational disorder and/or clustering effects lead to large dispersions in the Mn-Mn exchange interactions, in the case of fixed Mn concentration. Moreover, theoretical results for the ground-state total energies for several configurations indicate the importance of a proper consideration of disorder in treating temperature and annealing effects

Rendimento de massa e características morfológicas de Crotalaria ochroleuca em populações de plantas.

JIPE 2013

Correlação entre volume globular e Famacha em caprinos pertencentes ao quarto lote de animais resistentes e susceptíveis a Haemonchus contortus.

Resumo: O objetivo deste trabalho foi correlacionar o volume globular com a coloração da mucosa ocular verificada pelo método Famacha de controle da verminose em caprinos pertencentes ao quarto lote de animais com diferentes graus de resistência na região semi-árida do Nordeste brasileiro. Baseados na contagem de ovos por grama de fezes (OPG), caprinos jovens F2 (½ sangue Anglo-nubiana x ½ sangue Saanen) foram classificados em resistentes (n=12) e susceptíveis (n=12) a Haemonchus contortus. Semanalmente observou-se a coloração da mucosa ocular e foi realizada a coleta de sangue para a determinação do volume globular. Para as análises de correlação entre VG e Famacha, foram considerados os valores de VG≤19%, VG≤22% e VG≤27% e dos graus Famacha 3, 4 e 5 como ponto de corte. O ponto de corte de VG19 não foi adequado para avaliar a correlação entre a coloração da mucosa ocular e o Famacha, sendo que o valor de VG22 apresentou maior sensibilidade, portanto mais adequado para esta espécie. Correlation between packed cell volume and Famacha in goats belonging to fourth batch from resistant and susceptible animals to Haemonchus contortus Abstract: The aim of this study was to correlate the packed cell volume with Famacha method to endoparasites control in goats with different degrees of resistance in semi-arid region of the Northeast of Brazil. Based on EPG (eggs per gram) counts, young goats F2 (½ blood Anglo-Nubian x Saanen ½ blood) were classified as resistant (n=12) and susceptible (n=12) to Haemonchus contortus infections. Weekly, the color of ocular mucosal was observed according to Famacha method and blood was was collected to determine the packed cell volume. For correlation analysis between packed cell volume and Famacha were considered values of VG?19%, VG?22% and VG?27% and The VG19 it was not an ideal parameter to evaluated the correlation between the color of ocular mucosa and Famacha, whereas the VG22 was the most sensible, being the best value to be used as cutoff in goats F2

The SOAR Gravitational Arc Survey - I: Survey overview and photometric catalogs

We present the first results of the SOAR (Southern Astrophysical Research) Gravitational Arc Survey (SOGRAS). The survey imaged 47 clusters in two redshift intervals centered at $z=0.27$ and $z=0.55$, targeting the richest clusters in each interval. Images were obtained in the $g'$, $r'$ and $i'$ bands using the SOAR Optical Imager (SOI), with a median seeing of 0.83, 0.76 and 0.71 arcsec, respectively, in these filters. Most of the survey clusters are located within the Sloan Digital Sky Survey (SDSS) Stripe 82 region and all of them are in the SDSS footprint. Photometric calibration was therefore performed using SDSS stars located in our SOI fields. We reached for galaxies in all fields the detection limits of $g \sim 23.5$, $r \sim 23$ and $i \sim 22.5$ for a signal-to-noise ratio (S/N) = 3. As a by-product of the image processing, we generated a source catalogue with 19760 entries, the vast majority of which are galaxies, where we list their positions, magnitudes and shape parameters. We compared our galaxy shape measurements to those of local galaxies and concluded that they were not strongly affected by seeing. From the catalogue data, we are able to identify a red sequence of galaxies in most clusters in the lower $z$ range. We found 16 gravitational arc candidates around 8 clusters in our sample. They tend to be bluer than the central galaxies in the lensing cluster. A preliminary analysis indicates that $\sim 10$ of the clusters have arcs around them, with a possible indication of a larger efficiency associated to the high-$z$ systems when compared to the low-$z$ ones. Deeper follow-up images with Gemini strengthen the case for the strong lensing nature of the candidates found in this survey.Comment: 17 pages, 11 figures (most of them multi-panel) MNRAS (2013

Produção de biomassa e características fisiológicas do feijoeiro cv. Pérola na safra de inverno.

O objetivo deste trabalho foi avaliar os índices fisiológicos de plantas de feijão cv. Pérola semeadas em diferentes datas, na safra de inverno