Corals growing on the flanks of Banda Api, Indonesia, contain records of volcanic activity which occurred in May, 1988. Ashfall killed portions of some massive coral colonies (Porites lobata), resulting in the formati...
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Corals growing on the flanks of Banda Api, Indonesia, contain records of volcanic activity which occurred in May, 1988. Ashfall killed portions of some massive coral colonies (Porites lobata), resulting in the formation of death surfaces. These surfaces were preferential sites for extensive bioerosion and incorporation of volcanic ash into underlying skeletal pores. Subsequent coral regeneration resulted in the preservation of death/regrowth surfaces overlying trapped volcanic ash. An orange-colored iron-rich chemical precipitate is preserved in the skeletons of corals which survived the volcanic event. These distinct orange bands are contemporaneous with the death/regrowth surfaces. The iron banding is interpreted as being a product of hydrothermal activity which accompanied volcanism. X-radiographs of coral skeletons confirm that the timing of formation of both the death surfaces and the orange banding is coincident with the 1988 eruption. The features preserved in these corals may be valuable proxy indicators of volcanic events in analogous recent and ancient environments.
An emerging technology for wireless connectivity provides one of the best combinations of bandwidth, coverage area, and cost for a wireless data network. It also teaches important lessons about software-hardware inter...
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An emerging technology for wireless connectivity provides one of the best combinations of bandwidth, coverage area, and cost for a wireless data network. It also teaches important lessons about software-hardware interface design. To support this vision of ubiquitous connectivity, we are studying issues of wireless and mobile computing at the network, system, and application levels. Our two main goals are to provide seemingly continuous connectivity for mobile hosts, and to support system- and application-level adaptation to dynamically changing network characteristics. We are investigating changes and extensions to standard networking application program interfaces (APIs) that will allow well-written applications to deal gracefully with widely varying network characteristics. When switching between available services, network characteristics can change significantly, even while an application is running.
In order to assess the potential of lactobacilli to cause serious infections, we studied the prevalence of bacteremia due to Lactobacillus species during a 4-year period (1989-1992) in southern Finland, which has a po...
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In order to assess the potential of lactobacilli to cause serious infections, we studied the prevalence of bacteremia due to Lactobacillus species during a 4-year period (1989-1992) in southern Finland, which has a population of about 2.5 million. Among 3,317 blood culture isolates, lactobacilli were identified in eight patients, five of whom had a severe disease predisposing to bacteremic complications. The eight strains isolated were identified to the species level and typed by carbohydrate fermentation tests and by direct sequencing of enzymatically amplified 16S rRNA. The results did not provide evidence that any particular species or subspecies of Lactobacillus was the cause of the infections;no infections caused by isolates similar to the recently introduced dairy probiotic strain, Lactobacillus GG (ATCC 53103), were observed. The data show an infrequent association of lactobacilli with bacteremic infections in spite of the ubiquitous presence of these organisms in the gastrointestinal tract and their widespread consumption in fermented milks;thus, there is strong evidence that their pathogenic potential is very low.
This paper explores an approach to social choice which is an alternative to Arrow's social welfare function. We consider 'best fit' social rankings for any individual preferences through the definition of ...
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This paper explores an approach to social choice which is an alternative to Arrow's social welfare function. We consider 'best fit' social rankings for any individual preferences through the definition of levels of agreement between preferences and rankings. We thereby avoid the pairwise approach of Arrow's independence and Pareto conditions, and we demonstrate the possibility of non-dictatorial social choice. Mie consider the rationality implications of a non-unique outcome, and determine additional properties, including majority-consistency, of the Condorcet process for determining the rankings. The approach also allows an interpretation of Sen's 'impossibility of a Paretian liberal' in terms of individual agreement.
Statistical analysis of dated documents from Sneferu's reign implies that the cattle count took place more often annually than biennially. Thus the ‘twenty-fourth occasion of the (cattle) count’, which is the hi...
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Statistical analysis of dated documents from Sneferu's reign implies that the cattle count took place more often annually than biennially. Thus the ‘twenty-fourth occasion of the (cattle) count’, which is the highest date yet known for Sneferu and which exceeds the 24 years allotted him in the Turin Canon, cannot be equivalent to 45 regnal years but rather to about 30. On the basis of the dates preserved on blocks from the king's Red Pyramid, a model can be constructed to demonstrate that about eleven years were required for its construction. This period accords well with a reign of about 30 years.
Practitioners of computer music often need to store sound as sampled digital data on hard disks, digital audio tapes, or compact discs. Discusses a few of the many ways that sound data can be stored in computer files,...
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Practitioners of computer music often need to store sound as sampled digital data on hard disks, digital audio tapes, or compact discs. Discusses a few of the many ways that sound data can be stored in computer files, and describes several of the file formats that are in common use for this purpose. Extensive references are given to printed and network accessible machine readable documentation and source code resources.
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