A Reimagining of the Chacoan World

A new paradigm of the Chacoan world is presented, wherein Chaco Canyon is considered to be a mostly unoccupied architectural complex that functioned primarily as a pilgrimage destination. Chaco was the political, religious, and social focal point of people living in outlying regions. The resident population of the Canyon consisted of a small number of caretakers, charged with maintaining great house structures, food supplies, and their ceremonial contents. Chacoan chiefdoms were mostly located in large, well-watered, agriculturally-based communities situated at the base of mountains that ring the San Juan Basin, e.g., the Chuskas. Chiefly elites lived year-round in those areas, but during pilgrimages they occupied Canyon great houses associated with their respective dynasties, whereas their subjects occupied small houses situated on the Canyon floor. Not having 2000 people in the Canyon renders large-scale irrigated agriculture and massive importation of food unnecessary and provides an adequate explanation for the small number of burials found in the Canyon. Se presenta un nuevo paradigma del mundo chacoano, en el que el Cañón del Chaco es considerado como un complejo arquitectónico mayoritariamente desocupado que funcionaba principalmente como destino de peregrinación. Chaco fue el centro político, religioso y social de las personas que viven en regiones al aire libre. La población residente del Cañón consistía en un pequeño número de cuidadores, encargados de mantener grandes estructuras de casas, suministros de alimentos y su contenido ceremonial. Las jefaturas chacoanas se encontraban principalmente en grandes comunidades agrícolas bien regadas situadas en la base de montañas que anillan la cuenca de San Juan, por ejemplo, los Chuskas. Principalmente las élites vivían durante todo el año en esas áreas, pero durante las peregrinaciones ocuparon grandes casas del Cañón asociadas con sus respectivas dinastías, mientras que sus súbditos ocupaban pequeñas casas situadas en el suelo del Cañón. No tener 2000 personas en el Cañón hace que la agricultura de regadío a gran escala y la importación masiva de alimentos sean innecesarias y proporciona una explicación adecuada para el pequeño número de entierros encontrados en el Cañón

Galaxy Formation Spanning Cosmic History

Over the past several decades, galaxy formation theory has met with significant successes. In order to test current theories thoroughly we require predictions for as yet unprobed regimes. To this end, we describe a new implementation of the Galform semi-analytic model of galaxy formation. Our motivation is the success of the model described by Bower et al. in explaining many aspects of galaxy formation. Despite this success, the Bower et al. model fails to match some observational constraints and certain aspects of its physical implementation are not as realistic as we would like. The model described in this work includes substantially updated physics, taking into account developments in our understanding over the past decade, and removes certain limiting assumptions made by this (and most other) semi-analytic models. This allows it to be exploited reliably in high-redshift and low mass regimes. Furthermore, we have performed an exhaustive search of model parameter space to find a particular set of model parameters which produce results in good agreement with a wide range of observational data (luminosity functions, galaxy sizes and dynamics, clustering, colours, metal content) over a wide range of redshifts. This model represents a solid basis on which to perform calculations of galaxy formation in as yet unprobed regimes.Comment: MNRAS accepted. Extended version (with additional figures and details of implementation) is available at http://www.galform.or

Induced Innovation or a Paradox of Environmental Regulation?

In a seeming paradox, bluegrass seed production in the State of Washington increased following imposition of a statewide ban on stubble burning in 1996. Despite forecasts that alternative production practices would increase the cost of producing bluegrass seed so much that the industry would be driven from the state, production in the years 1997-2003 was higher than in any seven-year period in recorded history. This study seeks to explain why this occurred. Several hypotheses are put forward and systematically tested. The final hypothesis, induced innovation, cannot be formally tested because of data limitations, but it is examined by an assessment of innovations that occurred contemporaneously with the ban and by corroborative statistical evidence. The evidence is consistent with this hypothesis as a plausible explanation.Environmental Economics and Policy,

3D Seismic Mapping of Probable Tripolitic Chert Bodies in Osage County, Oklahoma

The Mississippi Lime play is an important recent oil and gas development in the mid-continent of the United States. In April of 2007, Chesapeake Energy Corporation used horizontal drilling and tracing to bring the Howell 1-33H well online. This well revitalized the Mississippi Lime play, expanding exploration with potential Mississippian reservoirs. The Mississippian section is a complex carbonate reservoir containing several distinct lithologies. An important Mississippian lithology known from outcrops in Arkansas and Missouri is tripolitic chert, or tripolite; a bleach, highly diagenetically altered, silica rock with high porosity, low density, and high permeability. Tripolite is an important reservoir target with the broader Mississippi dense lime play, but should not be confused with Mississippi Chat reservoirs found in Kansas or Oklahoma which commonly are described as cherty paleosols, chert breccia or conglomerates. Acoustic impedance of tripolite is quite low, leading to a characteristic strong negative amplitude anomaly in 3D seismic data (i.e., a lithology bright spot). This study presents techniques and results for seismic mapping of probable tripolite occurrences in the Wild Creek 3D seismic survey of Osage County, Oklahoma. Resolution estimates are also presented, along with preliminary reflection coefficient calculations indicating observed amplitude anomalies represent tripolite embedded in dense Mississippian limestone, a stratigraphic relationship in agreement with recent outcrop observations

Recent cytheracean ostracodes from McMurdo Sound and the Ross Sea, Antarctica

36 p., 4 pl., 25 fig.http://paleo.ku.edu/contributions.htm

On-line monitoring of water quality parameters

Chapter one summarises the development of UK legislation for the protection of the aquatic environment, and highlights current EC legislative requirements for water quality. The need for on-line water quality monitoring and the alternative instrumental approaches to it are discussed, together with the philosophy of "easy care instrumentation" and water industry requirements for online analysers. A simple spectrophotometric FI system is proposed for the on-line determination of a range of water quality parameters.The following chapter details instrumentation used in the FI system, emphasising the solid-state photometric detector.Development of an FI manifold for the determination of aluminium in potable and treated waters is covered in the next chapter. The method, based on complexation of aluminium with pyrocatechol violet is compared with a standard Driscoll procedure. Details of the construction and testing of a fully automated FI instrument are also given.Chapter four describes the development of a modular automated FI monitor with a PC compatible STEbus based computer system. Successful operation of this monitor is illustrated by its application to the determination of residual coagulants (aluminium and iron). Full details of software routines for control, processing and validation are given together with results from a tap water trial for dissolved aluminium.The FI determination of residual iron by its complexation with ferene S, and the application of the optimised method in the STEbus based monitor is detailed in chapter five.In the final chapter the use of on-line FI oxidation procedures for the determination of dissolved organic carbon are examined. The oxidation of a wide range of organic species to carbon dioxide using a silver catalysed persulphate reaction, enhanced with UV irradiation and a stopped-flow procedure is described. The sequential determination of inorganic and organic carbon without separation of the fractions is also investigated