950 resultados para World History


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BACKGROUND: Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world's largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. RESULTS: The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. CONCLUSIONS: Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity.

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K’gari-Fraser Island, the world's largest barrier sand island, is at the crossroads of World Heritage status, due to destructive environmental use in concert with climate change. Will K’gari-Fraser Island exemplify innovative, adaptive management or become just another degraded recreational facility? We synthesize the likely impact of human pressures and predicted consequences on the values of this island. World-renown natural beauty and ongoing biological and geological processes in coastal, wetland, heathland and rainforest environments, all contribute to its World Heritage status. The impact of hundreds of thousands of annual visitors is increasing on the island's biodiversity, cultural connections, ecological functions and environmental values. Maintaining World Heritage values will necessitate the re-framing of values to integrate socioeconomic factors in management and reduce extractive forms of tourism. Environmentally sound, systematic conservation planning that achieves social equity is urgently needed to rectify historical mistakes and update current management practices. Characterizing and sustaining biological refugia will be important to retain biodiversity in areas that are less visited. The development of a coherent approach to interpretation concerning history, access and values is required to encourage a more sympathetic use of this World Heritage environment. Alternatively, ongoing attrition of the islands values by increased levels of destructive use is inevitable.

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This paper sets out an ambitious critique of contemporary political scientists, political historians and others concerned with the history of democracy. It argues that overwhelmingly the history of democracy relies on an overtly Eurocentric narrative that emphasizes the keystone moments of Western civilization. According to this narrative, democracy has a clear trajectory that can be traced from ancient experiments with participatory government in Greece and to a lesser extent in Rome, through the development of the British parliament, the American Declaration of Independence and the French Revolution, and then finally onto the triumphant march of the liberal model of democracy across the globe over the last 200 years, particularly under Western tutelage. Histories of democracy that focus exclusively on these events not only privilege Europe and its successful colonies, but also miss the broader human story of the struggle for and achievement of democracy.This presents us with a distinct challenge. For those whose heritage does not include a direct link to Greek assemblies, the American Congress or the French Revolution, the ‘standard history of democracy’ provides a distant and exclusive narrative, which limits one’s ability to embrace democracy. This paper concludes by noting that, as democracy spreads out across the world today, political scientists not only need to break down the intellectual orthodoxy that democracy has exclusively Western roots, but also to embrace a more global view of democracy as a political practise that has been present at various times and in sometimes unfamiliar ways in the complex histories and rich cultural traditions of most of the people of the earth.

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Somatic growth patterns represent a major component of organismal fitness and may vary among sexes and populations due to genetic and environmental processes leading to profound differences in life-history and demography. This study considered the ontogenic, sex-specific and spatial dynamics of somatic growth patterns in ten populations of the world's largest lizard the Komodo dragon (Varanus komodoensis). The growth of 400 individual Komodo dragons was measured in a capture-mark-recapture study at ten sites on four islands in eastern Indonesia, from 2002 to 2010. Generalized Additive Mixed Models (GAMMs) and information-theoretic methods were used to examine how growth rates varied with size, age and sex, and across and within islands in relation to site-specific prey availability, lizard population density and inbreeding coefficients. Growth trajectories differed significantly with size and between sexes, indicating different energy allocation tactics and overall costs associated with reproduction. This leads to disparities in maximum body sizes and longevity. Spatial variation in growth was strongly supported by a curvilinear density-dependent growth model with highest growth rates occurring at intermediate population densities. Sex-specific trade-offs in growth underpin key differences in Komodo dragon life-history including evidence for high costs of reproduction in females. Further, inverse density-dependent growth may have profound effects on individual and population level processes that influence the demography of this species.

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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.

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The objectives of this article are to provide a short history of dentistry and dental education in Brazil and to analyze the nature of its development to date. The databases consulted are those provided by the Brazilian Federal Council of Dentistry, Brazilian Ministry of Health, Brazilian Ministry of Education, National Institute of Studies and Educational Research Anisio Teixeira, and Brazilian Institute of Geography and Statistics. Formal dental education in Brazil started in the late nineteenth century with the creation of courses annexed to existing schools of medicine in Rio de Janeiro and Bahia. Today, there are 191 institutions of higher education nationwide granting degrees in dentistry (137 private [71.7 percent] and fifty-four public [28.3 percent]), with a total of 17,157 student positions offered annually. These schools graduate around 10,000 professionals per year-one of the highest rates in the world. Both the distribution of schools of dentistry and of dentists varies among the regions of the country, with the greatest concentrations in major metropolitan centers with high population density, resulting in limited coverage in the more deprived regions. A review of epidemiological data for oral health and distribution of dentists in Brazil indicates that there is a lack of systematic planning for the allocation of the dental workforce and a lack of consideration of regional needs in the development of dental training programs in Brazil today.

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The encrustation of Paleozoic rhynchonelliform brachiopods has been studied for decades, but modern brachiopods have not received similar scrutiny. The discovery of abundant subtropical brachiopods from the Southeast Brazilian Bight provides an unprecedented opportunity to assess epibiont abundance, diversity, and encrustation patterns in modern brachiopod assemblages. Across the outer shelf, encrustation frequencies vary among taxa, from mean values of 0.45% for Platidia to 9.3% for Argyrotheca. Encrustation frequencies for Bouchardia increase from 1.6% on the outer shelf to 84% on the inner shelf Larger valves are encrusted more frequently, and epibionts preferentially colonize valve interiors. Increased encrustation on the inner shelf may reflect the greater surface area of larger hosts, longer exposure of dead shells, water-mass characteristics, sedimentation rates, productivity, or other factors that vary with depth. Inner-shelf brachiopods exhibit encrustation frequencies comparable to those reported for epifaunal bivalves. The epibiont fauna is dominated by bryozoans and serpulids, with minor roles played by spirorbids, bivalves, barnacles, foraminifera, algae, and other taxa. Epibiont abundance at each site is highly variable, but sites are similar in rank importance of epibiont taxa. A different suite of epibionts colonized Paleozoic brachiopods, but similar patterns of encrustation have been observed, including preferential settlement according to valve morphology. These results provide a baseline for evaluating the encrustation of modern bivalves and ancient brachiopods, and may elucidate the macroevolutionary history of epibionts and their relationship to their hosts.

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Since their domestication in the Neolithic, cattle have belonged to our cultural heritage. The reconstruction of their history is an active field of research 1 that contributes to our understanding of human history. Archeological data are now supplemented by analyses of modern and ancient samples of cattle with DNA markers of maternal, paternal, or autosomal inheritance. The most recent genetic data suggest that maternal lineages of taurine cattle originated in the Fertile Crescent with a possible contribution of South-European wild cattle populations, while zebu cattle originate from the Indus Valley. Subsequently, cattle accompanied human migrations, which led to the dispersal of domestic cattle of taurine, indicine, or mixed origin over Asia, Africa, Europe, and the New World. This has resulted in their adaptation to different environments and considerable variation in appearance and performance. More recently, rational management of breeding led to international movements of sires, which again changed the global patterns of genetic diversity.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This article proposes to analyze the results of a research conducted in the São Paulo Immigrants Memorial, whose purpose was to work with an agreement between the state of São Paulo and the Union, according to which the state committed itself to receive, from May 1947 to 1952, immigrants of different European nationalities. Such immigrants had a specific characteristic that conferred them a peculiar status in the eyes of the United Nations, given the fact that they originated from Germany and Austria and where either displaced persons or refugees who could not or did not want to return to their homelands, for several reasons. Italians represented only 0,12% of this group. Italian immigration to Brazil became significant only after 1950, due to the Brazil-Italy immigration agreements.

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Foreword Alicia Bárcena and introduction by Jorge Máttar

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The giant river prawn, Macrobrachium cf. rosenbergii, is one of the most cultivated freshwater prawns in the world and has been introduced into more than 40 countries. In some countries, this prawn is considered an invasive species that requires close monitoring. Recent changes in the taxonomy of this species (separation of M. rosenbergii and M. dacqueti) require a re-evaluation of introduced taxa. In this work, molecular analyses were used to determine which of these two species was introduced into Brazil and to establish the geographic origin of the introduced populations that have invaded Amazonian coastal waters. The species introduced into Brazil was M. dacqueti through two introduction events involving prawns originating from Vietnam and either Bangladesh or Thailand. These origins differ from historical reports of the introductions and underline the need to confirm the origin of other exotic populations around the world. The invading populations in Amazonia require monitoring not only because the biodiversity of this region may be affected by the introduction, but also because admixture of different native haplotypes can increase the genetic variability and the likelihood of persistence of the invading species in new habitats.

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Stingrays are a group of rays - cartilaginous fish related to sharks - that have whiplike tails with barbed, usually venomous spines and are found around the world, especially the marine species. Despite recent reports of accidents involving these fish, they are not aggressive, reacting only when stepped on or improperly handled. Injuries by stingrays are seldom mentioned by historians, although they have always been present in riverine communities of inland waters and in South American coasts. Indeed, envenomations by stingrays are quite common in freshwater and marine fishing communities. Although having high morbidity, such injuries are neglected because they have low lethality and usually occur in remote areas, which favor the use of folk remedies. In the present review article, historical aspects of injuries caused by stingrays in Brazil and their distribution on the coast of Sao Paulo state and riverine communities of the North, Midwest and Southeast regions were studied. In addition, other aspects were analyzed such as clinical features, therapeutic methods, preventive measures and trends in occurrence of these accidents in the country, particularly in areas in which freshwater stingrays had not been previously registered, being introduced after breaching of natural barriers.

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Located in southeastern Brazil, the Santos Estuary has the most important industrial and urban population area of South America. Since the 1950`s, increased urbanization and industrialization near the estuary margins has caused the degradation of mangroves and has increased the discharge of sewage and industrial effluents. The main objectives of this work were to determine the concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) in sediment cores in order to investigate the input of these substances in the last 50 years. The PAHs analyses indicated multiple sources of these compounds (oil and pyrolitic origin), basically anthropogenic contributions from biomass, coal and fossil fuels combustion. The distribution of PAHs in the cores was associated with the formation and development of Cubatao industrial complex and the Santos harbour, waste disposal, world oil crisis and the pollution control program, which results in the decrease of organic pollutants input in this area. (C) 2011 Elsevier Ltd. All rights reserved.