13,953 research outputs found
Intraday stock volatility : a New Zealand perspective : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Business in Finance at Massey University
Open-to-open, close-to-close, open-to-close (trading) and close-to-open (non-trading) time periods are examined for dually and non-dually listed stocks in an attempt to explain the volatility patterns which were observed in the New Zealand Stock Exchange. The time period analysed covers the 1997 calendar year. The intraday volatility pattern for the New Zealand Stock Exchange showed similar results to previous studies performed on large exchanges around the world. That is, when the return variances are plotted against the trading time they follow a distinct U-shaped curve, caused by high volatility at the opening and closing of the market. Previous studies have found that the high volatility experienced at the opening of the market results from the long non-trading period prior to the opening. This was examined by analysing the open-to-open to close-to-close variance ratio for both dually and non-dually listed stocks. The explanation that the long non-trading period prior to the opening of the market is a major cause of the volatility experienced at the market opening is not supported by the results found in this study. The results obtained from this study show that the high volatility at the market opening is associated with high capitalised stocks. A low open-to-close (trading) to close-to-open (non-trading) variance ratio was observed in the New Zealand market. Previous research has attributed this low ratio to dually listed stocks continuing to trade during the non-trading overnight period of the domestic market. The findings in this study contradict this explanation and suggest that it is low capitalised stocks that are associated with the low trading to non-trading variance ratio observed in the New Zealand Stock Exchange
Pharmacological cardioversion for atrial fibrillation and flutter*
Atrial fibrillation is the commonest cardiac dysrhythmia. It is associated with significant morbidity and mortality. There are two approaches to the management of atrial fibrillation: controlling the ventricular rate or converting to sinus rhythm in the expectation that this would abolish its adverse effects.
The objective of this review was to assess the effects of pharmacological cardioversion of atrial fibrillation in adults on the annual risk of stroke, peripheral embolism, and mortality.
We made a thorough search for existing evidence in the following databases: the Cochrane Controlled Trials Register (Issue 3, 2002), MEDLINE (2000 to 2002), EMBASE (1998 to 2002), CINAHL (1982 to 2002), Web of Science (1981 to 2002). We also handsearched the following journals: Circulation (1997 to 2002), Heart (1997 to 2002), European Heart Journal (1997-2002), Journal of the American College of Cardiology (1997-2002) and selected abstracts published on the web site of the North American Society of Pacing and Electrophysiology (2001, 2002). We selected trials based on the following criteria: randomised controlled trials or controlled clinical trials of pharmacological cardioversion versus rate control in adults (>18 years) with acute, paroxysmal or sustained atrial fibrillation or atrial flutter, of any duration and of any aetiology.
We identified two completed studies AFFIRM (n=4060) and PIAF (n=252). We found no difference in mortality between rhythm control and rate control - relative risk 1.14 (95% confidence interval 1.00 to 1.31). Both studies show significantly higher rates of hospitalisation and adverse events in the rhythm control group and no difference in quality of life between the two treatment groups. In AFFIRM there was a similar incidence of ischaemic stroke, bleeding and systemic embolism in the two groups. Certain malignant dysrhythmias were significantly more likely to occur in the rhythm control group. There were similar scores of cognitive assessment in both groups. In PIAF, cardioverted patients enjoyed an improved exercise tolerance but there was no overall benefit in terms of symptom control or quality of life.
There is no evidence that pharmacological cardioversion of atrial fibrillation to sinus rhythm is superior to rate control. Rhythm control is associated with more adverse effects and increased hospitalisation. It does not reduce the risk of stroke. These conclusions cannot be generalised to all people with atrial fibrillation as most of the patients included in these studies were relatively older (>60 years) with significant cardiovascular risk factors
A Sum Greater Than the Parts: What States Can Teach Each Other About Charter Schooling
States with a significant charter sector know firsthand that the success or failure of a charter school is not a matter of chance, but subject to variances in state laws and a state's educational, political, and regulatory climate. In this report, Sara Mead and Andrew J. Rotherham draw on the experiences of 12 states, proposing those lessons that are necessary for charter school quality and growth
Challenged Index: Why Newsweek's List of America's 100 Best High Schools Doesn't Make the Grade
Some schools on Newsweek's list of America's Top 100 high schools have large achievement gaps, grossly shortchange disadvantaged groups, and have a substantial number of drop-outs
Introducing the transport impacts of E-business project
E-Business is expected to dramatically change the way business is conducted internationally, nationally, within states and at the local area level. Moreover, these changes are very likely to happen well within the planning time frames required for provision of transport infrastructure and services. This paper introduces a study to investigate: how will the transport task change; what will be affected; and how can the transport system respond? The work, a joint initiative of the National Transport Secretariat [NTS], and the CSIRO/QUT Built Environment Research Alliance, in collaboration with Queensland Department of Public Works, is intended to assist Australian business and government pro-actively address the transport issues arising from e-business. E-commerce is growing exponentially: worldwide e-commerce revenues are estimated to reach $US1300 billion by 2003. Growth in electronic communications within companies which, together with e-commerce between companies, B2B, or between business and consumers, B2C, make up e-business, is even more significant. The magnitude and speed of both these changes increase the urgency of planning, for their impacts provide forecasting challenges. A study approach is described to consider direct impacts from e-business on Australian transport, derived demand for travel or delivery as other businesses prosper and transport related constraints to e-business in the next five to ten years. Base line information collection: includes a review of literature and information about trends in e-business then transport and e-Business; interviews with stakeholder/experts in planning agencies, e-business companies and transport/logistics firms across Australia; appraisal of data available for on-going assessment; and contact with international experts. Trends and impact assessment: National trends will be estimated and very important impacts or very urgent impacts selected via a ranking and rating process. Transport related productivity gains will be assessed; trends in regional Australia and international trends and experience will be reported with a final assessment of opportunities and threats for Australia. Outputs: A series of working papers and final reports; a user friendly database of contacts, publications and data availability information for update; a research framework for identification of policy and planning levers to maximise benefits to Australia from national and global e-business activity
Performance of carrot and onion seed primed with beneficial microorganisms in glasshouse and field trials
Beneficial microorganisms (Clonostachys rosea IK726, Pseudomonas chlororaphis MA342, Pseudomonas fluorescens CHA0, Trichoderma harzianum T22 and Trichoderma viride S17a) were successfully applied to carrot and onion seed during a commercial drum priming process. Applied microorganisms were recovered above the target of at least 1 × 105 cfu g−1 seed following subsequent application of pesticides to the seed according to standard commercial practices of film-coating carrot and pelletting onion seed. Two glasshouse experiments consistently showed that priming improved emergence of carrot seed and that C. rosea IK726 further improved emergence time. Priming improved emergence of onion seed in one glasshouse experiment, but had an unexpected negative effect on emergence in the second experiment, possibly due to the proliferation of an unidentified indigenous microorganism during priming, becoming deleterious in high numbers. In this experiment, the application of beneficial microorganisms during priming negated this effect and significantly improved emergence. For each crop, a series of field trials was also carried out over three years, at two different sites each year. Although some positive effects of different seed treatments were seen on emergence or yield in individual field trials, no consistent effects were found for primed or microorganism-treated seed across all sites and years. However, a combined analysis of data for all years and sites indicated that pesticide application did consistently improve emergence and yield for both carrot and onion. This is the first comprehensive study assessing glasshouse and field performance of carrot and onion seed primed with beneficial microorganisms during a commercial process of drum priming in the UK
Function generator eliminates necessity of series summation
Diode generator using four building-block circuits produces complex waveforms without the necessity of series summation. This highly specialized method of producing complex waveforms requires less power than present methods and uses simpler circuitry
Induced matter: Curved N-manifolds encapsulated in Riemann-flat N+1 dimensional space
Liko and Wesson have recently introduced a new 5-dimensional induced matter
solution of the Einstein equations, a negative curvature Robertson-Walker space
embedded in a Riemann flat 5-dimensional manifold. We show that this solution
is a special case of a more general theorem prescribing the structure of
certain N+1-dimensional Riemann flat spaces which are all solutions of the
Einstein equations. These solutions encapsulate N-dimensional curved manifolds.
Such spaces are said to "induce matter" in the sub-manifolds by virtue of their
geometric structure alone. We prove that the N-manifold can be any maximally
symmetric space.Comment: 3 page
Detecting Beyond-Einstein Polarizations of Continuous Gravitational Waves
The direct detection of gravitational waves with the next generation
detectors, like Advanced LIGO, provides the opportunity to measure deviations
from the predictions of General Relativity. One such departure would be the
existence of alternative polarizations. To measure these, we study a single
detector measurement of a continuous gravitational wave from a triaxial pulsar
source. We develop methods to detect signals of any polarization content and
distinguish between them in a model independent way. We present LIGO S5
sensitivity estimates for 115 pulsars.Comment: submitted to PR
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