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Woods DC  Chuan RL 《Science (New York, N.Y.)》1982,216(4550):1118-1119
The size distributions of fine particles measured at tropospheric altitudes in the periphery of the eruption plume formed during the 17 April 1979 eruption of Soufriere Volcano and in the low-level effluents on 15 May 1979 were found to be bimodal, having peak concentrations at geometric mean diameters of 1.1 and 0.23 micrometers. Scanning electron microscopy and energy-dispersive x-ray analysis of the samples revealed an abundance of aluminum and silicon and traces of sodium, magnesium, chlorine, potassium, calcium, and iron in the large-particle mode. The submicrometer-sized particles were covered with liquid containing sulfur, assumed to be in the form of liquid sulfuric acid.  相似文献   
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OBJECTIVE: To determine the distribution for limbs and bones in horses with fractures of the proximal sesamoid bones and relationships with findings on palmarodorsal radiographic images. SAMPLE POPULATION: Proximal sesamoid bones obtained from both forelimbs of cadavers of 328 racing Thoroughbreds. PROCEDURE: Osteophytes; large vascular channels; and fracture location, orientation, configuration, and margin distinctness were categorized by use of high-detail contact palmarodorsal radiographs. Distributions of findings were determined. Relationships between radiographic findings and fracture characteristics were examined by use of chi2 and logistic regression techniques. RESULTS: Fractures were detected in 136 (41.5%) horses. Biaxial fractures were evident in 109 (80%) horses with a fracture. Osteophytes and large vascular channels were evident in 266 (81%) and 325 (99%) horses, respectively. Medial bones typically had complete transverse or split transverse simple fractures, indistinct fracture margins, > 1 vascular channel that was > 1 mm in width, and osteophytes in abaxial wing and basilar middle or basilar abaxial locations. Lateral bones typically had an oblique fracture and distinct fracture margins. Odds of proximal sesamoid bone fracture were approximately 2 to 5 times higher in bones without radiographic evidence of osteophytes or large vascular channels, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Biaxial fractures of proximal sesamoid bones were common in cadavers of racing Thoroughbreds. Differences between medial and lateral bones for characteristics associated with fracture may relate to differences in fracture pathogeneses for these bones. Osteophytes and vascular channels were common findings; however, fractures were less likely to occur in bones with these features.  相似文献   
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This paper demonstrates how disasters create sites of degradation – potent spaces of upheaval and engagement – that are readily filled and exploited by evangelical Christian groups. In doing so, it explores how disasters provide opportunities for evangelical groups to gain a foothold in localities where Christian presence, and evangelical praxis, may otherwise be restricted. Drawing on qualitative data collected in Sri Lanka throughout 2010–2011, two comparative case studies are presented that reveal the strategies of evangelical Christian praxis in and through sites of environmental and political degradation. Specifically, the case studies reveal how evangelical groups pursue ‘outside‐in’ and ‘inside‐out’ strategies of salvation, which, by blurring the boundaries of religion and relief, can lead to the formation of new hierarchies of power.  相似文献   
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