The Petrogenesis Of The Penmaenmawr Intrusion, North Wales

The Penmaenmawr Intrusion forms a prominent hill on the north Wales coast and consists of a very fine- to medium-grained microdiorite. Previous studies have considered the Penmaenmawr Intrusion to be related to the extrusive rocks of the Llewelyn Volcanic Group, that were erupting in early Caradoc times in a back arc basin associated with subduction due to the closure of the lapetus Ocean to the northwest. The objective of this study was to examine the mineralogical and geochemical variations within the intrusion in order to investigate its petrogenesis. Seventy samples were collected for petrological examination and geochemical analysis and the results were used to model possible magmatic processes. This study proposes that the Penmaenmawr Intrusion was the result of two emplacements of magma from an underlying, already fractionated and layered, magma chamber. Initial injections of magma took place along the southern boundary and in the east of the present intrusion resulting in the very finegrained rocks at the margins of the intrusion. The second, larger emplacement, with a slightly more basic composition forms the main body of the intrusion. Local mixing between the two batches of magma took place along their common boundary blurring their junctions and some localised mixing also took place during the transport and emplacement of the second batch of magma, which served to obscure the evidence for the original compositional layering of the underlying magma chamber. Following emplacement, the Penmaenmawr Intrusion was variably altered forming a range of secondary minerals. This study proposes that the alteration is mainly due to the ingress of hydrothermal fluids along faults and shear planes during two alteration episodes. The first associated with emplacement where hot fluids, originating from the cooling magma, caused changes to the original minerals and the second associated with sub-greenschist facies metamorphism during the Acadian regional metamorphic event of early to mid Devonian times

When would the intellectual background make a difference? or professors have been important for a long time, but what kind of professors?

Medieval accounting history affords a fertile ground for studying the impact of the intellectual background on the development of accounting itself. In such a study, four hypotheses can be proposed: that the intellectual background affects accounting only when it reaches out towards accounting practice; that this outreach occurs only when intellectuals have direct, personal contact with accounting practice; that developments in law, philosophy, and related humanities are important; and that developments in mathematics are not important

Introduction of Arabic numerals in European accounting

The general adoption of Arabic numerals by European bookkeepers occurred at least five hundred years after their introduction to the scholarly world. The early availability yet late adoption of this numeration is shown to be due to several factors, not least to interplay between the culture and cultural conservatism of clerks and the educational and intellectual changes of the early Italian Renaissance

Improving Asset Price Prediction When All Models are False

This study considers three alternative sources of information about volatility potentially useful in predicting daily asset returns: daily returns, intraday returns, and option prices. For each source of information the study begins with several alternative models, and then works from the premise that all of these models are false to construct a single improved predictive distribution for daily S&P 500 index returns. The prediction probabilities of the optimal pool exceed those of the conventional models by as much as 5.29%. The optimal pools place substantial weight on models using each of the three sources of information about volatility

Babel and Babble in Benjamin and Burke

Drawing on the works of Walter Benjamin and Kenneth Burke, this essay argues that the philosophical conditions and conclusions of rhetoric and translation are the same: both trace their origins to the primal fall of language, whether after the Fall from Eden or the curse of Babel, and both find their horizons in an ultimate linguistic motive that, oddly enough, typifies ordinary language use

The Ottawa ankle rules for the use of diagnostic X-ray in after hours medical centres in New Zealand

Aims: The aims of this study were to measure baseline use of Ottawa ankle rules (OAR), validate the OAR and, if appropriate, explore the impact of implementing the Rules on X-ray rates in a primary care, after hours medical centre setting. Methods: General practitioners (GPs) were surveyed to find their awareness of ankle injury guidelines. Data concerning diagnosis and X-ray utilisation were collected prospectively for patients presenting with ankle injuries to two after hours medical centres. The OAR were applied retrospectively, and the sensitivity and specificity of the OAR were compared with GPs’ clinical judgement in ordering X-rays. The outcome measures were X-ray utilisation and diagnosis of fracture. Results: Awareness of the OAR was low. The sensitivity of the OAR for diagnosis of fractures was 100% (95% CI: 75.3 – 100) and the specificity was 47% (95% CI: 40.5 – 54.5). The sensitivity of GPs’ clinical judgement was 100% (95% CI: 75.3 – 100) and the specificity was 37% (95% CI: 30.2 – 44.2). Implementing the OAR would reduce X-ray utilisation by 16% (95% CI: approx 10.8 – 21.3). Conclusions: The OAR are valid in a New Zealand primary care setting. Further implementation of the rules would result in some reduction of X-rays ordered for ankle injuries, but less than the reduction found in previous studies.Accident Compensation Corporation of New ZealandOtago Universit