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51.
Climate Change During the Last Deglaciation in Antarctica   总被引:1,自引:0,他引:1  
Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated.  相似文献   
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Brazilian spotted fever (BSF) is a highly lethal disease caused by Rickettsia spp. and is transmitted by ticks of the genus Amblyomma. Understanding the epidemiology of BSF in each region can help direct health surveillance actions. The objective of this study was to determine the spatial distribution of vectors and the incidence of BSF in the state of São Paulo. Spatial analysis included confirmed BSF cases between 2009 and 2019; occurrences were registered by municipalities of the state. There were 752 confirmed BSF cases, with incidences ranging between 0.01 and 10.37/10,000 inhabitants. Moran's Global Index for BSF was 0.20 (p = .001), which was indicative of spatial dependence. Moran's map located a cluster of 20 high priority municipalities for BSF and showed that Amblyomma sculptum is the vector involved in Rickettsia rickettsii transmission in these locations. Spatial analysis identified clusters formed by 47, 20 and seven significant municipalities for the presence of A. sculptum, Amblyomma aureolatum and Amblyomma ovale vectors, respectively. Surveillance and prevention actions are necessary in areas that are at high risk for BSF and in areas where the presence of vectors was significant.  相似文献   
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Phosphorus, manganese, sulfur (S), lead, and strontium of atmospheric total suspended particulate matter, sampled during the rainy season and the dry season 2002 at the Ilha Grande Island (Rio de Janeiro State, Brazil) have been analyzed by XRF techniques. The results showed total mean concentrations of 27?±?16 ng P m-3, 11?±?7 ng Mn m-3, 159?±?126 ng S m-3, 4.3?±?2.6 ng Pb m-3, and 208?±?148 ng Sr m-3. Generally, there is no clear influence of the two different climatic periods on the concentrations of most analyzed trace elements, with exception of sulfur the mean concentration of which, during the dry season, is about 60% higher than during the rainy season. This is probably due to biomass burning, a common practice in the Brazilian Southeast and Amazon region and/or to the presence of marine aerosols. The linear correlation coefficients strongly suggest the same source for P, Pb, and Mn. Some Pb, Mn, and P concentrations are in the range of typical values of urban areas. Potential sources of such elements are the urban and industrial emissions from the States of Rio de Janeiro and/or São Paulo.  相似文献   
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On the Morphology of the Fossa ovalis in the adult Dog Heart 1. The Fossae ovales of 77 adult dog hearts are not a partly persistent foramen ovale. 2. They are always translucent. 3. According to their shape there are 6 different types: pyriform (most frequently), triangulare, elliptical, ovale, reniform and round (most rarely). 4. The middle dimensions are 0.6227 cm. laterolateral and 0.3525 cm. craniocaudal. 5. The middle depth is 0.15 cm.  相似文献   
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The morphological development of the seminiferous epithelium in the pig at different ages ( Sus scrofa , Landrace breed)
In the Pig, Landrace breed, were observed, at different ages, among 15 to 210–220 days, the morphological patterns of the seminiferous epithelium that lines "cordonal" tubules at 15 to 30 days of postnatal and "luminal" tubules at 120 to 210–220 days of age. Although some morphological events of cellular differentiation were observed at 120 days, and the spermatogenesis process apparently could be observed at 180–190 days, really the overall characteristics of the cellular differentiation in the seminiferous epithelium, with the presence of luminal spermatozoa, were observed at 210–220 days of age. This last stage is considered as the puberal age.  相似文献   
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Canine tooth fracture is common in dogs. Application of an esthetic and durable restoration may be challenging in veterinary dental practice. This study used traditional human dental laboratory methods to evaluate fracture strength of intact dog canine teeth and fractured teeth that had been restored by reattachment of the tooth fragment. The results showed that the teeth restored by reattachment of the tooth fragment supported a test load equal to 45.4 % of the load necessary to fracture intact canine teeth.  相似文献   
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