Suchergebnisse

Distribution of gold in the Earth's crust -- 1.1 Introduction -- 1.2 Gold in rock-forming minerals -- 1.3 Gold in igneous rocks -- 1.4 Gold in sediments and sedimentary rocks -- 1.5 Gold in metamorphic rocks -- 1.6 Concluding summary -- 1.7 Mineral data -- References -- The hydrothermal geochemistry of gold -- 2.1 Introduction -- 2.2 The inorganic chemistry of gold -- 2.3 Gold complexing in hydrothermal solutions -- 2.4 Gold deposition -- 2.5 Summary -- References -- 3 Archaean lode gold deposits -- 3.1 Introduction -- 3.2 Nature of deposits -- 3.3 Regional distribution -- 3.4 Constraints on genetic models -- 3.5 Genetic models -- 3.6 Tectonic setting of gold mineralization -- 3.7 Potential exploration significance -- 3.8 Brief summary -- References -- 4 Phanerozoic gold deposits in tectonically active continental margins -- 4.1 Introduction -- 4.2 Distribution of Phanerozoic lode gold deposits in space and time -- 4.3 Geological and geochemical characteristics -- 4.4 Genetic models -- 4.5 Comparisons of Phanerozoic mesothermal deposits to other types of gold Mineralization -- 4.6 Conclusions -- References -- 5 Epithermal gold deposits in volcanic terranes -- 5.1 Introduction -- 5.2 Exploration case studies -- 5.4 Active geothermal systems -- 5.5 Metal transport in epithermal systems -- 5.6 Physico-chemical conditions in the depositional regime -- 5.7 Epithermal deposits through geologic time -- 5.8 Exploration -- 5.9 Summary -- References -- 6 Intrusion-related gold deposits -- 6.1 Introduction -- 6.2 Geotectonic settings -- 6.3 Intrusion-hosted stockwork/disseminated deposits -- 6.4 Deposits in carbonate rocks -- 6.5 Stockwork, disseminated and replacement deposits in non-carbonate rocks -- 6.6 Breccia-hosted deposits -- 6.7 Vein-type deposits -- 6.8 Deposit interrelationships and metal zoning -- 6.9 Genetic considerations -- 6.10 Possible relationships with other gold deposit types -- 6.11 Concluding remarks -- References -- 7 The geology and origin of Carlin-type gold deposits -- 7.1 Introduction -- 7.2 Classification of Carlin-type deposits -- 7.3 Regional geological and tectonic setting -- 7.4 Characteristics of the deposits -- 7.5 Ore deposit models -- 7.6 Exploration guidelines -- 7.7 Summary -- References -- 8 Auriferous hydrothermal precipitates on the modern seafloor -- 8.1 Introduction -- 8.2 Gold in seafloor polymetallic sulphide deposits -- 8.3 Mineralogy and geochemistry of gold in seafloor hydrothermal systems -- 8.4 Gold in sub-seafloor stockwork mineralization -- 8.5 Gold in hydrothermal plumes and associated metalliferous sediments -- 8.6 Transport and deposition of gold in seafloor hydrothermal systems -- 8.7 Secondary enrichment of gold in supergene sulphides and gossans -- 8.8 Gold in ancient seafloor hydrothermal systems -- References -- 9 Ancient placer gold deposits -- 9.1 Introduction -- 9.2 Geological setting -- 9.3 The palaeosurfaces -- 9.4 The placer sediments -- 9.5 Metamorphism -- 9.6 Structural control -- 9.7 Summary -- References -- 10 Geochemical exploration for gold in temperate, arid, semi-arid, and rain forest terrains -- 10.1 Introduction -- 10.2 Geochemical signatures of gold mineralization -- 10.3 Examples and case histories -- 10.4 Operating procedures -- 10.5 Alternative sampling techniques -- 10.6 Conclusions -- References -- 11 Geochemical exploration for gold in glaciated terrain -- 11.1 Introduction -- 11.2 Glacial dispersal -- 11.3 Glacial stratigraphy and ice-movement directions -- 11.4 Sampling and analytical methods -- 11.5 Occurrence of gold in till and soil and the effects of weathering -- 11.6 Drift prospecting for gold -- 11.7 Source of placer gold in glaciated terrains -- 11.8 Conclusions and future trends -- References -- 12 Geophysical exploration for gold -- 12.1 Introduction -- 12.2 Geological and geophysical models -- 12.3 Exploration strategy and methods -- 12.5 Conclusions -- 12.6 Glossary of geophysical terms -- References -- 13 Economics of gold deposits -- 13.1 Introduction -- 13.2 Market setting -- 13.3 Gold-mine production -- 13.4 Economic evaluation of gold deposits -- 13.5 Characteristics of economic gold deposits -- 13.6 Conclusion -- References.

Medicare is the largest health care program in the country, providing medical care to 38 million aged and disabled Americans. Concerns over rapid cost increases and the imminent insolvency of the Medicare Hospital Insurance trust fund led to enactment of sweeping Medicare legislation as part of the Balanced Budget Act of 1997. Preliminary estimates indicate that this legislation will result in program savings of $150 billion in the first five years and will postpone the depletion of the Hospital Insurance fund from the year 2001 until about 2010. While the Balanced Budget Act significantly reduces Hospital Insurance expenditure in the long range, serious deficits are still expected when the "baby boom" generation reaches retirement. The Medicare Supplementary Medical Insurance trust fund is automatically in financial balance, but policy makers remain concerned about continuing rapid cost increases. A new National Bipartisan Commission on the Future of Medicare will attempt to determine effective solutions to these long-range problems.

Este texto evalúa el concepto de la cultural profesoral, observandolo desde el mundo empresarial y académico. Y analizandolo desde tres perspectivas: disciplinarias, profesional e institucional. Luego de analizar como estas se relacionan a creencias, normas, valores y supuestos del profesorado, concluimos el artículo con una discusión acerca de las implicaciones para los dirigentes de la educación superior de un enfoque cultural en el análisis del profesorado.

The current debate about how to provide housing for persons with persistent psychiatric disabilities should be informed by empirical information from a variety of sources.Data from a study of 17 residents discharged from Regeneration House Inc., illustrates the value of consumer perceptions in the evaluation of supportive housing. Extensive exploration of the positive and negative aspects of living in a group home from the perspective of experienced residents provides useful input for programme planning.The implications of the findings for the individual programme and the wider field are discussed.

"Statements of Hon. A. Piatt Andrew, of Massachusetts, Maj. R.L. Foster, U.S. Army, and others." ; Cover title. ; Mode of access: Internet.

Data were collected to determine if an additional menu sign, visible to restaurant customers as they waited in line to order food, would reduce both the amount of time taken to order food as well as the number of food-ordering errors. An A-B-A-B design was utilized in which ordering times and errors were recorded before the addition of a second menu sign, after the addition of the second sign, after the removal of the second sign, and after the reinstallation of the second menu sign. Results indicated that the additional menu sign led to a significant decrease in both ordering times and ordering errors. Without the second sign, customers took an average of 23.82 seconds to place an order and made an average of .26 errors. In the two sign intervention conditions, customers took an average of 6.48 seconds to order and made an average of .08 errors. The sign manipulation resulted in effect sizes of 1.18 for ordering times and .99 for ordering errors.