Learning to Understand: Mathematical Preparation of Prospective Teachers

This paper describes the development of a two-course sequence in mathematics content for prospective elementary teachers. Community college and university personnel collaborated to develop a course sequence that would prepare prospective elementary teachers to teach mathematics with an understanding of concepts to support their abstract mathematical knowledge. The strategy was to begin with a broad vision and then focus on the smaller pieces which would achieve that vision. The course changes are validated by documents published by various educational and mathematical groups advocating an increased emphasis on teaching for understanding rather than rote learning. Significant change is difficult without support from colleagues and sufficient time, both necessary to the change process. The noteworthy components of Austin Community College’s revised course are a safe environment in which students become independent learners and written communication as an integral part of the course resulting in students who have increased their conceptual understanding. As a result of taking the course, students accept responsibility for their own learning, have increased self-confidence, and show enthusiasm for mathematics. While requiring a major commitment from faculty, the results are well worth the effort

Demand Forecasting for New Local Rail Services: A Case Study of a New Service Between Leicester and Burton-On- Trent

Preston, J. and Wardman, M. (1988) "Demand Forecasting for New Local Rail Services: A Case Study of a New Service between Leicester and Burton-on-Trent". Workina Paver 260, Institute for Transport Studies, University of Leeds. This paper assesses the potential for a new rail service between Leicester and Burton-on-rent. In order to do this, three sets of demand forecasts were produced. These were based on Revealed Preference (RP) models that had been developed in West Yorkshire, a Stated Intentions (SI) survey of the Leicester-Burton corridor and Stated Preference (SP) models developed for the Ashby/ Coalville -and Outer Leicester areas. It was found that these three approaches gave a wide range of forecasts but it was felt that the SI survey, adjusted for the findings from the SP models, were likely to give the most reliable estimates of usage. As a result, it was concluded that, given patronage growth over time, total usage of the line would amount to between 3,000 and 4,000 trips on an average day. The demand forecasts were then used as input to an evaluation framework which took into account capital costs, operating costs, revenue and time savings. Even if actual usage reached the upper level of our forecasts it was shown that, although operating costs would be covered, only some of the capital costs would be paid back. Consideration of user time savings strengthens the case for the scheme but even so a return on capital would still not be achieved. Therefore, it was concluded that the case for a rail service between Leicester and Burton is, at best, marginal, although a number of ways to continue the feasibility study are suggested

Forecasting Motorists Long Term Behaviour in the Greater Nottingham Area

This report outlines work carried out to assess the factors that, in the medium and long term, may influence motorists' mode choice in the Greater Nottingham area. This work was based on four Stated Preference (SP) experiments that examined the choice between car and ordinary bus, car and bus-based park and ride, car and express bus and between departure times for car users. Just over 6,000 self completion questionnatres were distributed at random to residents in 28 wards. Over 1.700 usable responses were returned. representing a response rate of 29%. Despite a number of problems, a series of four strategic forecasting models were developed. These incoporated some important findings including that motorists value delay highly, value parking costs more highly than petrol costs and value adjusting their departure time less highly than in-vehicle time. The four forecasting models were then used to examine five scenarios; the introduction of park and ride, the effect of projected 2001 road traffic speeds, the effect of petrol cost increases, the effect of parking cost increases and the effect of decreasing bus in-vehicle time. Although there were a number of technical difficulties. our forecasts suggest that decreases in speeds, parking costs and petrol costs will not halt the growth in road traffic but will slow it down. Where possible motorists are more likely to change the time of theirjourney than theirmode. For dramatic changes in mode split both a big stick and big carrot are probably required. The big stick might be provided by some of parking control or road pricing, whilst the carrot might be some form of a high quality, fast bus network (or indeed other forms of public transport with a segregated right of way). The role of park and ride is likely to be relatively marginal but may be worth pursuing if part of an overall traffic management policy. There was little evidence from our models of there being any critical "thresholds" or "trigger points". However, many of the processes we have examined seem to have cumulative impacts and our forecasts identified the doubling of car journey times as being a possible "catalyst" which is likely to be achieved in the early part of the next centur

Axial rotation and turbulence of RR ab stars: the Peterson Conundrum revisited

We calibrate and then use the relation between equivalent width (EW) and full-width-half-maximum (FWHM) of metallic absorption lines in the spectra of RR Lyrae stars to estimate a new upper limit of Vrot sini less than or equal to 6 km/s on their axial equatorial rotational velocities, and to derive the variations of macroturbulent velocities in their atmospheres during pulsation cycles. Finally, we present a simple way to estimate macroturbulent/rotational velocity from FWHM of the cross-correlation function.Comment: 15 pages, 7 figures, 1 table. EAS Publications Series.: "New advances in stellar physics: from microscopic to macroscopic processes", 27-31 May 2013, Roscoff, Franc

Cohort fertility patterns and breast cancer mortality among U.S. women, 1948-2003

Epidemiological research has shown that women who have early and numerous births have reduced risks of being diagnosed with breast cancer. We use U.S. Vital Statistics and Census data and age-period-cohort models to examine whether cohort fertility patterns are associated with breast cancer mortality rates among women aged 40 and older in 1948-2003. Cohorts marked by higher proportions childless at ages 15-24 and lower cumulative second birth rates at ages 15-29 have higher rates of breast cancer mortality. This is the first demonstration that cohort fertility patterns have left a clear imprint on trends in U.S. breast cancer mortality rates.age-period-cohort, breast cancer mortality, cohort fertility

Nitrogen uptake and the importance of internal nitrogen loading in Lake Balaton

1. The importance of various forms of nitrogen to the nitrogen supply of phytoplankton has been investigated in the mesotrophic eastern and eutrophic western basin of Lake Balaton.<br /> 2. Uptake rates of ammonium, urea, nitrate and carbon were measured simultaneously. The uptake rates were determined using N-15 and C-14 methodologies, and N-2-fixation was measured using the acetylene-reduction method. The light dependence of uptake was described with an exponential saturation equation and used to calculate surface-related (areal) daily uptake. <br /> 3. The contribution of ammonium, urea and nitrate to the daily nitrogen supply of phytoplankton varied between 11 and 80%, 17 and 73% and 1 and 15%, respectively. N- 2-fixation was negligible in the eastern basin and varied between 5 and 30% in the western region of the lake. The annual external nitrogen load was only 10% of that utilized by algae.<br /> 4. The predominant process supplying nitrogen to the phytoplankton in the lake is the rapid recycling of ammonium and urea in the water column, The importance of the internal nutrient loading is emphasized

The impact of EU enlargement on migration flows

This document is a report commissioned by the Home Office in order to assess the magnitude of potential migration flows to the UK after the enlargement of the European Union (EU). The countries which are expected to join the EU on 1 May 2004 are Cyprus, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia. The aim of the report is to provide extensive information that will be helpful in evaluating the migration potential from these countries to the UK. This is done by (i) describing the socio-economic situation of the accession countries nowadays and since the early 1990s and comparing it to that of the UK and Germany, (ii) critically reviewing the existing literature that attempts to predict the effects of the current EU enlargement on migration flows, (iii) analysing the so-called Southern enlargement (the accessions of Greece, Portugal and Spain) and comparing it to the current one, and (iv) presenting a quantitative analysis of the effect of the current enlargement on migration to the UK

Anti-deSitter gravitational collapse

We describe a formalism for studying spherically symmetric collapse of the massless scalar field in any spacetime dimension, and for any value of the cosmological constant $\Lambda$. The formalism is used for numerical simulations of gravitational collapse in four spacetime dimensions with negative $\Lambda$. We observe critical behaviour at the onset of black hole formation, and find that the critical exponent is independent of $\Lambda$.Comment: 4 pages, 2 figures, revtex4, version to appear in CQ

Rail Privatisation: The Practice – An Analysis of Seven Case Studies

After a brief description of the proposals for rail privatisation in Great Britain, this paper contrasts these with the proposals and experience in other countries around the world. The proposals and experience in other countries contain some elements of the British proposals, however, the 'open access' element that features strongly in the British proposals has never been experienced on any significant scale elsewhere. In conclusion, experience elsewhere may shed light on the likely outcome of some aspects of the British proposals, but other aspects such as 'open access' and vertical separation are still unknowns