Utilização da estatística espacial para analisar a dinâmica do feijão e da soja no Brasil, entre os anos de 1990 a 2013

Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Humanas, Departamento de Geografia, Programa de Pós-Graduação em Geografia, 2015.Neste trabalho foi analisada a dinâmica espacial-temporal de duas lavouras temporárias importantes para o Brasil, o feijão e a soja, para o período de 1990 a 2013. A escolha da soja foi justificada por ser responsável por inúmeras transformações no espaço agrário brasileiro recentemente, enquanto o feijão foi devido sua abrangência nacional e o predomínio de agricultores familiares. Foram verificadas as alterações em variáveis vinculadas ao crescimento agrícola: área colhida, produção e produtividade. Os dados secundários utilizados foram coletados junto à base PAM/IBGE. Investigouse a existência da autocorrelação espacial com a utilização do Índice de Moral Global (I), em seguida, identificado o perfil dos agrupamentos com aplicação do algoritmo Getis-OrdGi*; e, por fim, identificadas as regiões dos agrupamentos locais com a utilização do Índice de Moran Local. Como análise complementar foi utilizada a ferramenta Tabulação Cruzada (crosstab), o Teste Qui-Quadrado de Pearson e a Metodologia do Crescimento e Aceleração do Crescimento. Os resultados demonstraram que, para o feijão, houve uma considerável redução da área destinada ao cultivo, porém houve aumentos significativos na produção e na produtividade. Ficou evidente também a existência de diferenças e peculiaridades regionais na análise da produção dessa cultura no Brasil. A polarização da produção de feijão abrange regiões que compreendem a Região Central do PR, Sul de SP, Noroeste de MG, Sudeste de GO, Oeste da BA e recentemente a região central do MT. Para a cultura da soja verificou a manutenção e formação de novos agrupamentos Alto-Alto, nos Estados da Região Sul e Centro Oeste, como também a expansão para o Estado de RO e, mais recentemente, nas áreas de abrangência dos Cerrados, em TO, BA, MA e PI (MATOPIBA), Identificou-se nessa análise um valor crescente da área colhida, produção e produtividade. As causas desse aumento podem ser explicadas, principalmente, pela implementação de políticas públicas e avanços tecnológicos.In this work, we aimed to analyze spatial-temporal dynamics related to two important temporary crops in Brazil, bean and soybean for the period 1990 to 2013. The choice soybean is justified due to its role in recent changes in the Brazilian agrarian space. As for beans, its choice was due to its national coverage being produced on the family farms. The study analyses the changes in variables related to agricultural growth: Harvested area, production and productivity. Secondary data were collected from the base PAM/ IBGE. Autocorrelation was calculated using the Global Moran Index (R), the profile of the groups identified with application of Getis-Ord Gi * algorithm; and finally, identified regions of local cluster using the Local Moran Index. A complementary analysis is the Cross Tabulation (crosstab), the Pearson Chi-Square Test and Growth Methodology and Growth Acceleration tools were used. The results showed that, for beans, there was a considerable reduction of the area farmed, but there were significant increases in production and productivity. There are regional differences and peculiarities in analyzing the production of this crop in Brazil. The polarization of bean production covers more favored regions comprising the Central Region of PR, Southern SP, Northwest MG, Southeast GO, West BA and recently Central MT. For soybean the maintenance and formation of new clusters High-High in Southern and Midwest Regions States, as well as the expansion to the state of RO and, more recently, in areas covered by Cerrado, in TO, BA, MA and PI (MATOPIBA) an increasing amount of harvested area, production and productivity were found in this analysis. The causes of this increase can be explained mainly by the implementation of public policies and technological advances

Evaluation of wave loads on a new type of perforated caisson

Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.A new type of perforated breakwater has been tested combining the advantages of cylindrical geometry with stepped wave energy dissipation. Thus, the new type of caisson implies a significant reduction of maximum wave forces, as well as loads transmitted to the foundation in comparison with conventional vertical breakwater and other types of perforated caissons. Starting from a brief description of the model and test results, this paper describes the development of a methodology for the estimation of maximum wave loads on this type of breakwater, in order to become a generalisable tool for predesign purposes. Construction and installation constraints of this new type of caisson are also assessed. These need to be taken into account in order to keep some advantages from the proposed design, while noting the key factors from a practical point of view.Peer ReviewedPostprint (published version

From the financial crisis to the economic crisis The impact of the financial trouble of 2007-2008 on the growth of seven advanced countries

The financial crisis started in the United States in 2007 on the subprime mortgage market and, then, gradually spread to all financial markets and strongly impacted growth in the main advanced countries through the years 2008 and 2009. Given its scope and its subsequent uncertainty, we discuss the capacity of macroeconometric models estimated on the past to quantify its various transmission channels. We try to measure the total impact of the crisis on the economy of seven advanced countries and on the euro area as a whole using the macroeconomic multinational model NiGEM. During the years 2008 and 2009, Germany suffered from a particularly strong drop in world trade, which would explain more than a half of the effect of the crisis measured in this way in 2009. The United Kingdom and the United States may especially have been affected by wealth effects and a strong drop in their inner demand. This drop may partly have been due to credit tightening. Japan seems to be the most affected country in 2009: the drop in foreign trade was exacerbated by the appreciation of the yen and investment seems to have strongly over-reacted to the fall in activity. A contrario, the fact that France suffered from a less marked drop in output in 2009 might be explained by an absence of over-reaction in economic behaviours and less sensitivity to the fall in world trade.financial crisis, simulation, macroeconometric model, macro-financial linkages

The MESANGE model: re-estimation on National Accounts base 2000 / Part 2 Version with chained-linked volumes

Mesange is a medium-size quarterly macro-econometric model of the French economy (about 500 equations, three sectors). The model describes short-term Keynesian dynamics and its long-term equilibrium is driven by supply-side determinants. Its reestimation on data from the national accounts base 2000 with fixed-base volumes is presented in a recent working paper (Klein and Simon, 2010). This first version of the model has been optimized for simulation use. Other applications of the Mesange model (short-term forecasting, analyses of the past) required its adaptation to the published data from the quarterly accounts with chained-linked volumes, as well as the integration of the recent crisis episode. A second version of the Mesange model has, therefore, been developed for this purpose. This version is presented in this working paper. First, the problems raised for macroeconomic modelling by national accounts with chained-linked volumes are explained and the solutions chosen to adapt the model to these new conventions are discussed. The applications of the version of the model with chained-linked volumes are, then, explained and illustrated with examples. Last, the main reestimated equations are detailed. The differences with respect to the version of the model with fixed-base volumes are commented. They stem from estimations based on non-identical data, but also from the different uses made of the two versions of Mesange and the resulting various needs and constraints that have conditioned the methodological choices that have been made. As for the version of the model with chained-linked volumes, priority has been given to the quality of the adjustment to the data rather than to the underlying theoretical framework. Nonetheless, the philosophy and general structure of the two versions of the model remain very much alike.macroeconometric model, estimation, chained-linked volumes, short-term forecasting, contribution analysis

Spatial-Temporal patterns of bean crop in Brazil over the Period 1990–2013

The understanding of spatial dependence and distribution of agricultural production factors is a key issue for the territorial planning and regional development. This study evaluates the spatial-temporal dynamics of bean crops in Brazil over the period 1990–2013. Common bean (Phaseolus vulgaris L.) is one of the staple foods for the Brazilian population, with nationwide production and cultivated mostly by family farmers. The analyzed variables of this crop included harvested area, produced quantity, and average crop yield. We investigated spatial autocorrelations using the Global and Local Moran Index. The global spatial autocorrelation statistics demonstrated a general spatial dependence of bean production over Brazil, while the local spatial autocorrelation statistics detect statistically significant zones of high and low bean-production attributes. Maps of growth and acceleration rate of the variables were constructed, showing the areas that increased, decreased, or stagnated during the time series. The results showed a considerable reduction of the bean harvested area, but there were significant increases in produced quantity and average crop yield. Results showed distinct and significant patterns of bean-production variables in Brazilian territory over the different years. Regional differences and peculiarities are evident, emphasizing the need for directing investments to agricultural research and public policy

Room temperature chiral magnetic skyrmion in ultrathin magnetic nanostructures

Magnetic skyrmions are chiral spin structures with a whirling configuration. Their topological properties, nanometer size and the fact that they can be moved by small current densities have opened a new paradigm for the manipulation of magnetisation at the nanoscale. To date, chiral skyrmion structures have been experimentally demonstrated only in bulk materials and in epitaxial ultrathin films and under external magnetic field or at low temperature. Here, we report on the observation of stable skyrmions in sputtered ultrathin Pt/Co/MgO nanostructures, at room temperature and zero applied magnetic field. We use high lateral resolution X-ray magnetic circular dichroism microscopy to image their chiral N\'eel internal structure which we explain as due to the large strength of the Dzyaloshinskii-Moriya interaction as revealed by spin wave spectroscopy measurements. Our results are substantiated by micromagnetic simulations and numerical models, which allow the identification of the physical mechanisms governing the size and stability of the skyrmions.Comment: Submitted version. Extended version to appear in Nature Nanotechnolog

Severity-Related Changes of Bronchial Microbiome in Chronic Obstructive Pulmonary Disease

Bronchial colonization by potentially pathogenic microorganisms (PPMs) is often demonstrated in chronic obstructive pulmonary disease (COPD), but culture-based techniques identify only a portion of the bacteria in mucosal surfaces. The aim of the study was to determine changes in the bronchial microbiome of COPD associated with the severity of the disease. The bronchial microbiome of COPD patients was analyzed by 16S rRNA gene amplification and pyrosequencing in sputum samples obtained during stable disease. Seventeen COPD patients were studied (forced expiratory volume in the first second expressed as a percentage of the forced vital capacity [FEV1%] median, 35.0%; interquartile range [IQR], 31.5 to 52.0), providing a mean of 4,493 (standard deviation [SD], 2,598) sequences corresponding to 47 operational taxonomic units (OTUs) (SD, 17) at a 97% identity level. Patients were dichotomized according to their lung function as moderate to severe when their FEV1% values were over the median and as advanced when FEV1% values were lower. The most prevalent phyla in sputum were Proteobacteria (44%) and Firmicutes (16%), followed by Actinobacteria (13%). A greater microbial diversity was found in patients with moderate-to-severe disease, and alpha diversity showed a statistically significant decrease in patients with advanced disease when assessed by Shannon (ρ = 0.528; P = 0.029, Spearman correlation coefficient) and Chao1 (ρ = 0.53; P = 0.028, Spearman correlation coefficient) alpha-diversity indexes. The higher severity that characterizes advanced COPD is paralleled by a decrease in the diversity of the bronchial microbiome, with a loss of part of the resident flora that is replaced by a more restricted microbiota that includes PPMs

Ségrégation sociale au collège et relation école-famille. Quelques constats et outils d’analyse

Plusieurs recherches suggèrent que la relation école-famille est influencée par le contexte socioéconomique des établissements où elle se déroule. Ce chapitre propose une contribution à cette réflexion sous l’angle de la ségrégation sociale au collège. Dans un premier temps, nous illustrons en quoi le niveau et les formes de la ségrégation entre collèges, sur un territoire donné, peuvent y influencer les relations avec les familles. En particulier, les situations de forte ségrégation peuvent renforcer les difficultés rencontrées par les familles les plus éloignées de la culture scolaire. Dans un second temps, nous présentons des outils statistiques permettant de mieux caractériser cette ségrégation. Nous illustrons l’apport que de tels outils peuvent offrir en termes de contextualisation : du point de vue des recherches, en appui à des approches plus qualitatives, et du point de vue des politiques visant à mieux prendre en compte les situations de ségrégation

Les camarades influencent-ils la réussite et le parcours des élèves ? Une revue de littérature sur les effets de pairs dans l’enseignement primaire et secondaire

En éducation, les effets de pairs résultent des différents types d’interactions entre élèves, au sein d’une même classe ou d’un même établissement. Toutefois, caractériser la nature et mesurer l’influence de ces interactions pose des problèmes méthodologiques substantiels. Ce document vise à présenter les difficultés relatives à la mesure des effets de pairs en éducation, ainsi que les résultats des recherches qui leur ont été consacrées dans l’enseignement primaire et secondaire. Au sein d’un établissement, les élèves sont influencés par la composition socio-économique et le niveau scolaire de leurs pairs. Les élèves de milieu défavorisé, ou en difficulté scolaire, y sont en général plus sensibles. En raison de tels effets, les phénomènes de ségrégation peuvent aggraver les inégalités scolaires. Les résultats des recherches relatives aux effets de pairs ne sont toutefois pas convergents

Intergenerational inequalities since baby-boom

Cohorts born until the late 1940s benefited from a clear generational progress: from one generation to the next, the conditions for entering the labour market were more favourable, living standards increased regularly, access to education and homeownership was more common. These progresses strongly slowed down and even stopped, for generations born in the 1950s and 1960s. Early in their life course, the latter had to face the two oil shocks and the bad economic context that followed. The most recent generations are experiencing a mixed picture. Several years of good economic performance at the turn of the 2000s helped to increase again their standard of living in comparison to previous generations at the same age. Then, they benefited from low interest rates that facilitated again access to the property, despite rising property prices. However, this improvement appears to be very dependent on the macroeconomic environment, which can easily turn around. Inequalities between generations go together with inequalities within generations. In particular, access to employment is closely linked to educational level. Graduate people are more protected from unemployment and get a stable job more easily, but such an improvement is at the cost of a downgrading as regards wages and employment position. Non-graduates, meanwhile, are more dependent on economic conditions, not only at the end of their studies but also during the beginning of their careers. Finally, the fragility of this generational progress, and the increased importance of intergenerational transfers of wealth, could possibly lead to a widening of the gap between social classes or social origins. For instance, since the beginning of the 2000s, the access of younger generations to property has been improving again but the gap in property rates between social categories has been increasing.intergenerational inequalities, social inequalities, cohorts