901 resultados para Modern speleothems


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The Santana Cave is located at the Upper Ribeira Touristic State Park (PETAR-Parque Estadual Turistico do Alto Ribeira) in southern São Paulo State, Brazil. This paper describes Pb-210 activity concentration data in soda straw stalactites samples collected at Salao das Flores in Santana Cave that is a fossil tributary of the cave river. Non-expensive alpha counting following some analytical steps for extracting and depositing Pb-210 were used for providing the Pb-210 data. In the analyzed samples, Pb-210 values of increasingly older samples fitted an exponential curve, thus suggesting that the production of Pb-210 has been constant with time. Also, the near-ideal fit indicated that the growth was uniform and there was no break in the continuous growth. The soda straw growth rates were determined from the best fit to the exponential curve through the Pb-210 activity concentration. The results of the measurements allowed estimate a longitudinal rate corresponding to 1.3 mm/yr and a lateral rate of 0.01 mm/yr, which permitted calculate times of 70 years and 317-498 years for their formation, respectively. The lateral growth rate is compatible with values from studies of chemical weathering rates held under laboratory and natural conditions. (C) 2011 Elsevier Ltd. All rights reserved.

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This paper discusses the claim of the situatedness of research in both theoretical and applied linguistics and some of its implications and argues that it is linked to the performativity of all assertions, including scientific ones. More importantly, I argue that it is the regressive infinity of performativity that makes inevitable the passage from presumably 'dispassionate' research to militancy.

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An investigation was undertaken to test the effectiveness of two procedures for recording boundaries and plot positions for scientific studies on farms on Leyte Island, the Philippines. The accuracy of a Garmin 76 Global Positioning System (GPS) unit and a compass and chain was checked under the same conditions. Tree canopies interfered with the ability of the satellite signal to reach the GPS and therefore the GPS survey was less accurate than the compass and chain survey. Where a high degree of accuracy is required, a compass and chain survey remains the most effective method of surveying land underneath tree canopies, providing operator error is minimised. For a large number of surveys and thus large amounts of data, a GPS is more appropriate than a compass and chain survey because data are easily up-loaded into a Geographic Information System (GIS). However, under dense canopies where satellite signals cannot reach the GPS, it may be necessary to revert to a compass survey or a combination of both methods.

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This is a highly original study of possession by demons and their exorcism, which was rife in early modern times, focussing on the place where they were most prevalent, France. Catholics at the time believed that the devil was present everywhere, in the rise of the heretics, in the activities of witches, and even in the bodies of the pious young women. The rite of exorcism was intended to heal the possessed and show the power of the church - but it generated as many problems as it resolved. Possessed nuns endured frequently violent exorcisms, exorcists were suspected of conjuring devils, and possession itself came to be seen as a form of holiness, elevating several women to the status of living saints. Sarah Ferber offers a challenging study of one of the most intriguing phenomena of early modern Europe; looking also at the present day, it argues that early modern conflicts over the devil still carry an unexpected force and significance for western Christianity (from publisher).

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The establishment of modern sociology in Brazil was part of a thoroughgoing modernization of the country that began in the 1930s and the years immediately following World War II. The founding of the University of Sao Paulo made possible the systematic training of scientists devoted to teaching and research and broadened the way learning was understood. Florestan Fernandes was the outstanding personality among the first social scientists that the university produced, and the picture of the Brazilian sociologist today is largely inspired by his career. Enthusiasm and scientific rigor were the hallmarks of his approach. His early work reflects intellectuals` shared belief in the power of ideas to regenerate the nation, freeing it from a past that they condemned. The mature reflection of his later works retreats from this optimistic view, recognizing the emergence of modern society in Brazil as a complex process with mixed results.

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Background-Novel therapies have recently become available for pulmonary arterial hypertension. We conducted a study to characterize mortality in a multicenter prospective cohort of patients diagnosed with idiopathic, familial, or anorexigen-associated pulmonary arterial hypertension in the modern management era. Methods and Results-Between October 2002 and October 2003, 354 consecutive adult patients with idiopathic, familial, or anorexigen-associated pulmonary arterial hypertension (56 incident and 298 prevalent cases) were prospectively enrolled. Patients were followed up for 3 years, and survival rates were analyzed. For incident cases, estimated survival (95% confidence intervals [CIs]) at 1, 2, and 3 years was 85.7% (95% CI, 76.5 to 94.9), 69.6% (95% CI, 57.6 to 81.6), and 54.9% (95% CI, 41.8 to 68.0), respectively. In a combined analysis population (incident patients and prevalent patients diagnosed within 3 years before study entry; n = 190), 1-, 2-, and 3-year survival estimates were 82.9% (95% CI, 72.4 to 95.0), 67.1% (95% CI, 57.1 to 78.8), and 58.2% (95% CI, 49.0 to 69.3), respectively. Individual survival analysis identified the following as significantly and positively associated with survival: female gender, New York Heart Association functional class I/II, greater 6-minute walk distance, lower right atrial pressure, and higher cardiac output. Multivariable analysis showed that being female, having a greater 6-minute walk distance, and exhibiting higher cardiac output were jointly significantly associated with improved survival. Conclusions-In the modern management era, idiopathic, familial, and anorexigen-associated pulmonary arterial hypertension remains a progressive, fatal disease. Mortality is most closely associated with male gender, right ventricular hemodynamic function, and exercise limitation. (Circulation. 2010; 122: 156-163.)

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