Quasi-Biennial variations in helioseismic frequencies: Can the source of the variation be localized?

We investigate the spherical harmonic degree (l) dependence of the "seismic" quasi-biennial oscillation (QBO) observed in low-degree solar p-mode frequencies, using Sun-as-a-star Birmingham Solar Oscillations Network (BiSON) data. The amplitude of the seismic QBO is modulated by the 11-yr solar cycle, with the amplitude of the signal being largest at solar maximum. The amplitude of the signal is noticeably larger for the l=2 and 3 modes than for the l=0 and 1 modes. The seismic QBO shows some frequency dependence but this dependence is not as strong as observed in the 11-yr solar cycle. These results are consistent with the seismic QBO having its origins in shallow layers of the interior (one possibility being the bottom of the shear layer extending 5per cent below the solar surface). Under this scenario the magnetic flux responsible for the seismic QBO is brought to the surface (where its influence on the p modes is stronger) by buoyant flux from the 11-yr cycle, the strong component of which is observed at predominantly low-latitudes. As the l=2 and 3 modes are much more sensitive to equatorial latitudes than the l=0 and 1 modes the influence of the 11-yr cycle on the seismic QBO is more visible in l=2 and 3 mode frequencies. Our results imply that close to solar maximum the main influence of the seismic QBO occurs at low latitudes (<45 degrees), which is where the strong component of the 11-yr solar cycle resides. To isolate the latitudinal dependence of the seismic QBO from the 11-yr solar cycle we must consider epochs when the 11-yr solar cycle is weak. However, away from solar maximum, the amplitude of the seismic QBO is weak making the latitudinal dependence hard to constrain.Comment: 10 pages, 6 figures, accepted for publication in MNRA

An Investigation into Power from Pitch-Surge Point-Absorber Wave Energy Converters.

There is a worldwide opportunity for clean renewable power. The results from the UK Government's "Marine Energy Challenge" showed that marine energy has the potential to become competitive with other forms of energy. The key to success in this lies in a low lifetime-cost of power as delivered to the user. Pitch-surge point-absorber WECs have the potential to do this with average annual powers of around 2 MW in North Atlantic conditions from relatively small devices that would be economically competitive with other technologies and would be relatively easy to install and maintain. The paper examines the factors governing the performance of such devices and outlines their underlying theory Preliminary laboratory test results from a 1/100 scale pilot design are presented. It is hoped that more extensive development work will follow these promising early results. Engineering designs for devices based on these findings are outlined

Incidence and costs of unintentional falls in older people in the United Kingdom

STUDY OBJECTIVE: To estimate the number of accident and emergency (A&E) attendances, admissions to hospital, and the associated costs as a result of unintentional falls in older people. DESIGN: Analysis of national databases for cost of illness. SETTING: United Kingdom, 1999, cost to the National Health Service (NHS) and Personal Social Services (PSS). PARTICIPANTS: Four age groups of people 60 years and over (60–64, 65–69, 70–74, and 75) attending an A&E department or admitted to hospital after an unintentional fall. Databases analysed were the Home Accident Surveillance System (HASS) and Leisure Accident Surveillance System (LASS), and Hospital Episode Statistics (HES). MAIN RESULTS: There were 647 721 A&E attendances and 204 424 admissions to hospital for fall related injuries in people aged 60 years and over. For the four age groups A&E attendance rates per 10 000 population were 273.5, 287.3, 367.9, and 945.3, and hospital admission rates per 10 000 population were 34.5, 52.0, 91.9, and 368.6. The cost per 10 000 population was £300 000 in the 60–64 age group, increasing to £1 500 000 in the 75 age group. These falls cost the UK government £981 million, of which the NHS incurred 59.2%. Most of the costs (66%) were attributable to falls in those aged 75 years. The major cost driver was inpatient admissions, accounting for 49.4% of total cost of falls. Long term care costs were the second highest, accounting for 41%, primarily in those aged 75 years. CONCLUSIONS: Unintentional falls impose a substantial burden on health and social services

Solar cycle variations of large frequency separations of acoustic modes: Implications for asteroseismology

We have studied solar cycle changes in the large frequency separations that can be observed in Birmingham Solar Oscillations Network (BiSON) data. The large frequency separation is often one of the first outputs from asteroseismic studies because it can help constrain stellar properties like mass and radius. We have used three methods for estimating the large separations: use of individual p-mode frequencies, computation of the autocorrelation of frequency-power spectra, and computation of the power spectrum of the power spectrum. The values of the large separations obtained by the different methods are offset from each other and have differing sensitivities to the realization noise. A simple model was used to predict solar cycle variations in the large separations, indicating that the variations are due to the well-known solar cycle changes to mode frequency. However, this model is only valid over a restricted frequency range. We discuss the implications of these results for asteroseismology.Comment: 9 pages, 11 figures, accepted for publication in MNRAS, references updated, corrections following proof

Reliability of P mode event classification using contemporaneous BiSON and GOLF observations

We carried out a comparison of the signals seen in contemporaneous BiSON and GOLF data sets. Both instruments perform Doppler shift velocity measurements in integrated sunlight, although BiSON perform measurements from the two wings of potassium absorption line and GOLF from one wing of the NaD1 line. Discrepancies between the two datasets have been observed. We show,in fact, that the relative power depends on the wing in which GOLF data observes. During the blue wing period, the relative power is much higher than in BiSON datasets, while a good agreement has been observed during the red period.Comment: 7 pages, HELAS II: Helioseismology, Asteroseismology, and MHD Connections, conference proceedin

Empirical relations for the accurate estimation of stellar masses and radii

In this work, we have taken advantage of the most recent accurate stellar characterizations carried out using asteroseismology, eclipsing binaries and interferometry to evaluate a comprehensive set of empirical relations for the estimation of stellar masses and radii. We have gathered a total of 934 stars -- of which around two-thirds are on the Main Sequence -- that are characterized with different levels of precision, most of them having estimates of M, R, Teff, L, g, density, and [Fe/H]. We have deliberately used a heterogeneous sample (in terms of characterizing techniques and spectroscopic types) to reduce the influence of possible biases coming from the observation, reduction, and analysis methods used to obtain the stellar parameters. We have studied a total of 576 linear combinations of Teff, L, g, density, and [Fe/H] (and their logarithms) to be used as independent variables to estimate M or R. We have used an error-in-variables linear regression algorithm to extract the relations and to ensure the fair treatment of the uncertainties. We present a total of 38 new or revised relations that have an adj-R2 regression statistic higher than 0.85, and a relative accuracy and precision better than 10% for almost all the cases. The relations cover almost all the possible combinations of observables, ensuring that, whatever list of observables is available, there is at least one relation for estimating the stellar mass and radius.Comment: 49 Pages, 17 figures, 11 tables, accepted for publication in ApJ

Scanning Electron Micrographs of Mississippian Age Conodonts from Southwestern Virginia, West Virginia and Kentucky

A report submitted to the Faculty Research Committee by James R. Chaplin on August 30, 1978 on scanning electron micrographs of Mississippian Age conodonts from Southwestern Virginia, West Virginia and Kentucky

Love-melancholy : revolt against mourning

The aim of this paper is to consider the phenomena of love-melancholy through an object relations framework, conceiving of this phenomena as a revolt against mourning. The theoretical framework utilized is the early object relations concepts introduced by Freud in his 1917 paper Mourning and Melancholia and elaborated by object relations theorist Melanie Klein in her later works. Using the film Eternal Sunshine of the Spotless Mind (2004) as a case example, this writer identifies a developmental process that occurs in resolving the pain of love-melancholy, emphasizing mourning the lost love object as necessary for establishing hope for future attachments