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The Palaeolithic record of Warsash, Hampshire, UK: implications for late Lower and early Middle Palaeolithic occupation history of Southern Britain
This paper presents new work on the Lower and Middle Palaeolithic assemblages recovered from Pleistocene gravels of the River Test at Warsash, Hampshire. Historic map and artefact analyses enable the geological context to be established for substantial portions of the Warsash Palaeolithic record, which, when combined with new data relating to regional terrace stratigraphy and chronology, enables Warsash to be incorporated within regional and national Palaeolithic frameworks. Three key assemblages
are identified: (1) a handaxe-dominated assemblage associated with gravels of the Lower Warsash Terrace that is likely to relate to hominin occupation during MIS 9; (2) a Levallois assemblage probably related to sediments overlying the Lower Warsash Terrace and likely to represent occupation in late MIS 8 and/or MIS 7; (3) a handaxe-dominated assemblage recovered from gravels of the Hamble Terrace, which is likely to have been reworked from older terrace fragments. The presence at Warsash of ficrons, cleavers and plano-convex handaxes is confirmed and their potential chronological significance considered. The Levallois record of the Solent Basin is discussed, highlighting its impoverished nature relative to the rich Levallois record of the Thames Valley. It is argued that preservation bias and/or collection history have not played a major role in creating these differences. Instead, it is likely to represent the limited dispersal of Neanderthal populations further into Britain from an entry point in the southern North Sea Basin
The Birth and Growth of Neutralino Haloes
We use the Extended-Press-Schechter (EPS) formalism to study halo assembly
histories in a standard CDM cosmology. A large ensemble of Monte Carlo
random walks provides the {\it entire} halo membership histories of a
representative set of dark matter particles, which we assume to be neutralinos.
The first generation halos of most particles do not have a mass similar to the
free-streaming cut-off of the neutralino power spectrum, nor do they
form at high redshift. Median values are to and
to 8 depending on the form of the collapse barrier assumed in the
EPS model. For almost a third of all particles the first generation halo has
. At redshifts beyond 20, most neutralinos are not yet part
of any halo but are still diffuse. These numbers apply with little modification
to the neutralinos which are today part of halos similar to that of the Milky
Way. Up to 10% of the particles in such halos were never part of a smaller
object; the typical particle has undergone "accretion events' where
the halo it was part of falls into a more massive object. Available N-body
simulations agree well with the EPS predictions for an "ellipsoidal" collapse
barrier, so these may provide a reliable extension of simulation results to
smaller scales. The late formation times and large masses of the first
generation halos of most neutralinos imply that they will be disrupted with
high efficiency during halo assembly.Comment: 7 pages, 7 figure
The celebrity entrepreneur on television: profile, politics and power
This article examines the rise of the ‘celebrity entrepreneur’ on television through the emergence of the ‘business entertainment format’ and considers the ways in which regular television exposure can be converted into political influence. Within television studies there has been a preoccupation in recent years with how lifestyle and reality formats work to transform ‘ordinary’ people into celebrities. As a result, the contribution of vocationally skilled business professionals to factual entertainment programming has gone almost unnoticed. This article draws on interviews with key media industry professionals and begins by looking at the construction of entrepreneurs as different types of television personalities and how discourses of work, skill and knowledge function in business shows. It then outlines how entrepreneurs can utilize their newly acquired televisual skills to cultivate a wider media profile and secure various forms of political access and influence. Integral to this is the centrality of public relations and media management agencies in shaping media discourses and developing the individual as a ‘brand identity’ that can be used to endorse a range of products or ideas. This has led to policy makers and politicians attempting to mobilize the media profile of celebrity entrepreneurs to reach out and connect with the public on business and enterprise-related issues
Training pediatric health care providers in prevention of dental decay: results from a randomized controlled trial
Background: Physicians report willingness to provide preventive dental care, but optimal methods for their training and support in such procedures are not known. This study aimed to evaluate the effect of three forms of continuing medical education (CME) on provision of preventive dental services to Medicaid-enrolled children by medical personnel in primary care physician offices. Methods: Practice-based, randomized controlled trial. Setting: 1,400 pediatric and family physician practices in North Carolina providing care to an estimated 240,000 Medicaid-eligible children aged 0–3 years. Interventions: Group A practices (n = 39) received didactic training and course materials in oral health screening, referral, counseling and application of fluoride varnish. Group B practices (n = 41) received the same as Group A and were offered weekly conference calls providing advice and support. Group C practices (n = 41) received the same as Group B and were offered in-office visit providing hands-on advice and support. In all groups, physicians were reimbursed 43 per preventive dental visit. Outcome measures were computed from reimbursement claims submitted to NC Division of Medical Assistance. Primary outcome measure: rate of preventive dental services provision per 100 well-child visits. Secondary outcome measure: % of practices providing 20 or more preventive dental visits. Results: 121 practices were randomized, and 107 provided data for analysis. Only one half of Group B and C practices took part in conference calls or in-office visits. Using intention-to-treat analysis, rates of preventive dental visits did not differ significantly among CME groups: GroupA = 9.4, GroupB = 12.9 and GroupC = 8.5 (P = 0.32). Twenty or more preventive dental visits were provided by 38–49% of practices in the three study groups (P = 0.64). Conclusion: A relatively high proportion of medical practices appear capable of adopting these preventive dental services within a one year period regardless of the methods used to train primary health care providers.Gary D Slade, R Gary Rozier, Leslie P Zeldin, and Peter A Margoli
Sex and the Cinema: What American Pie Teaches the Young
This paper focuses upon the wildly successful blockbuster American Pie teenpics, especially American Pie 3 – the Wedding. I argue that these films, which are sited so securely within the visual and pedagogical machinery of Hollywood culture, are specifically designed to appeal to teenage male audiences, and to provide lessons in sex and romance. Movies like this are especially important as they are experienced by far more teenagers than, for example, instructional films or other classroom materials; indeed, as Henry Giroux has observed, "teens and youth learn how to define themselves outside of the traditional sites of instruction, such as the home and the school… Learning in the postmodern age is located elsewhere – in popular spheres that shape their identities, through forms of knowledge and desires that appear absent from what is taught in schools" (Giroux, 1997, p.49). In this paper I discuss whether the American Pie series is actually a "new age" effort which, via insubordinate performances of gender, contests the hegemonic field of signification which regulates the production of sex, gender and desire, or whether it is more accurately described as a retrogressive hetero-conservative opus with a veneer of sexual radicalism. In short, I intend to probe whether this filmic vector for sex education is all about the shaping of responsible, caring, vulnerable men, or is it guiding them to become just like their heterosexual, middle-class fathers? And whether, despite its riotous and raunchy advertising, American Pie really dishes up something spicy or something terribly wholesome instead
Geophysical constraints on the reliability of solar and wind power in the United States
We analyze 36 years of global, hourly weather data (1980–2015) to quantify the covariability of solar and wind resources as a function of time and location, over multi-decadal time scales and up to continental length scales. Assuming minimal excess generation, lossless transmission, and no other generation sources, the analysis indicates that wind-heavy or solar-heavy U.S.-scale power generation portfolios could in principle provide ∼80% of recent total annual U.S. electricity demand. However, to reliably meet 100% of total annual electricity demand, seasonal cycles and unpredictable weather events require several weeks’ worth of energy storage and/or the installation of much more capacity of solar and wind power than is routinely necessary to meet peak demand. To obtain ∼80% reliability, solar-heavy wind/solar generation mixes require sufficient energy storage to overcome the daily solar cycle, whereas wind-heavy wind/solar generation mixes require continental-scale transmission to exploit the geographic diversity of wind. Policy and planning aimed at providing a reliable electricity supply must therefore rigorously consider constraints associated with the geophysical variability of the solar and wind resource—even over continental scales
One simulation to fit them all - changing the background parameters of a cosmological N-body simulation
We demonstrate that the output of a cosmological N-body simulation can, to
remarkable accuracy, be scaled to represent the growth of large-scale structure
in a cosmology with parameters similar to but different from those originally
assumed. Our algorithm involves three steps: a reassignment of length, mass and
velocity units, a relabelling of the time axis, and a rescaling of the
amplitudes of individual large-scale fluctuation modes. We test it using two
matched pairs of simulations. Within each pair, one simulation assumes
parameters consistent with analyses of the first-year WMAP data. The other has
lower matter and baryon densities and a 15% lower fluctuation amplitude,
consistent with analyses of the three-year WMAP data. The pairs differ by a
factor of a thousand in mass resolution, enabling performance tests on both
linear and nonlinear scales. Our scaling reproduces the mass power spectra of
the target cosmology to better than 0.5% on large scales (k < 0.1 h/Mpc) both
in real and in redshift space. In particular, the BAO features of the original
cosmology are removed and are correctly replaced by those of the target
cosmology. Errors are still below 3% for k < 1 h/Mpc. Power spectra of the dark
halo distribution are even more precisely reproduced, with errors below 1% on
all scales tested. A halo-by-halo comparison shows that centre-of-mass
positions and velocities are reproduced to better than 90 kpc/h and 5%,
respectively. Halo masses, concentrations and spins are also reproduced at
about the 10% level, although with small biases. Halo assembly histories are
accurately reproduced, leading to central galaxy magnitudes with errors of
about 0.25 magnitudes and a bias of about 0.13 magnitudes for a representative
semi-analytic model.Comment: 14 pages, 12 figures. Submitted to MNRA
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