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Primality-testing Mersenne numbers
Report of a systematic review of Mersenne numbers 2^p-1 for p < 62982
Submerged in the mainstream? A case study of an immigrant learner in a New Zealand primary classroom
Immigrant children from diverse language backgrounds face not only linguistic challenges when enrolled in mainstream English-medium classrooms, but also difficulties adjusting to an unfamiliar learning community. The culture of primary school classrooms in New Zealand typically reflects conventions across three dimensions: interactional, instructional task performance and cognitive-academic development. All three dimensions are underpinned by the culturally specific discourse conventions involved in language socialisation. New learners may be helped by classmates or their teacher to understand and successfully use these conventions, but left on their own they may sink rather than swim. This is a case study of one Taiwanese 11-year old boy, 'John', who entered a New Zealand primary classroom midway through the school year. John's basic conversational ability was sound, but he did not possess the interactive classroom skills needed to operate in the new culture of learning. Selected from a wider study of the classroom, transcript data from audio-recorded excerpts of John's interactions over several months with his teacher and classmates are interpreted from perspectives derived from sociocultural and language socialisation theories. The article concludes with a brief consideration of the extent to which John constructed, or was constrained from constructing meaningful learning experiences, and suggestions for further research and reflection
Fluctuations in the Irreversible Decay of Turbulent Energy
A fluctuation law of the energy in freely-decaying, homogeneous and isotropic
turbulence is derived within standard closure hypotheses for 3D incompressible
flow. In particular, a fluctuation-dissipation relation is derived which
relates the strength of a stochastic backscatter term in the energy decay
equation to the mean of the energy dissipation rate. The theory is based on the
so-called ``effective action'' of the energy history and illustrates a
Rayleigh-Ritz method recently developed to evaluate the effective action
approximately within probability density-function (PDF) closures. These
effective actions generalize the Onsager-Machlup action of nonequilibrium
statistical mechanics to turbulent flow. They yield detailed, concrete
predictions for fluctuations, such as multi-time correlation functions of
arbitrary order, which cannot be obtained by direct PDF methods. They also
characterize the mean histories by a variational principle.Comment: 26 pages, Latex Version 2.09, plus seceq.sty, a stylefile for
sequential numbering of equations by section. This version includes new
discussion of the physical interpretation of the formal Rayleigh-Ritz
approximation. The title is also change
The dynamics of power and resistance in police interview discourse
This is a study of police interviewing using an integrated approach, drawing on CA, CDA and pragmatics. The study focuses on the balance of power and control, finding that in particular the institutional status of the participants, the discursive roles assigned to them by the context, and their relative knowledge, are significant factors affecting the dynamics of the discourse. Four discursive features are identified as particularly significant, and a detailed analysis of the complex interplay of these features shows that power and control are constantly under negotiation, and are always open to challenge and resistance. Further it is shown that discursive dominance is not necessarily advantageous to participants, due to the specific goals and purposes of the police interview context. A wider consideration of the context illustrates the contribution that linguistics can make to the use of police interview data as evidence in the UK criminal justice system
TESS Discovery of a Transiting Super-Earth in the Mensae System
We report the detection of a transiting planet around Mensae (HD
39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The
solar-type host star is unusually bright (V=5.7) and was already known to host
a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered
planet has a size of and an orbital period of 6.27
days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays
a 6.27-day periodicity, confirming the existence of the planet and leading to a
mass determination of . The star's proximity and
brightness will facilitate further investigations, such as atmospheric
spectroscopy, asteroseismology, the Rossiter--McLaughlin effect, astrometry,
and direct imaging.Comment: Accepted for publication ApJ Letters. This letter makes use of the
TESS Alert data, which is currently in a beta test phase. The discovery light
curve is included in a table inside the arxiv submissio
‘An almost continuous picture of sordid vice’: The Keeler Affair, the Profumo Scandal and ‘Political’ Film Censorship in the 1960s
In 1963, the Profumo affair brought Christine Keeler to public attention and transformed her, briefly, into one of the most talked about women in the world. Seeking to exploit her notoriety, Topaz Films entered into an agreement with Keeler to make a cinematic version of her life story, The Keeler Affair. This article explores some of the controversies surrounding The Keeler Affair, especially in terms of the way in which the British Board of Film Censors dealt with the film. The Keeler Affair was submitted to the BBFC on two occasions – once when it was completed and then again in 1969 when Keeler's memoirs were serialised in the News of the World – and was rejected both times. On the second occasion, The Keeler Affair was also submitted to, and rejected by, the Greater London Council. The article seeks to establish some of the political factors that shaped the BBFC's and the GLC's attitudes towards politically contentious films, and demonstrates that the decisions made by the censors were guided not simply by the content of The Keeler Affair, but also by personal relationships, shared Establishment attitudes, concerns about public perceptions of the film industry and a desire not to be drawn into political controversies. Consequently, the article serves to reinforce the idea that censorship is best understood as a dynamic process shaped by a host of determining factors, many of which might best be described as extra- or para-cinematic
Vibrational and structural properties of glass: Advances from a combined modeling approach
We present experimental measurements and ab initio simulations of the crystalline and amorphous phases of . The calculated Raman, infrared, and vibrational density of states (VDOS) spectra are in excellent agreement with experimental measurements and contain the signatures of all the peculiar local structures of the amorphous phase, namely, bridging and nonbridging (double-bonded or terminal) oxygens and tetrahedral units associated with , , and species ( denotes the various types of tetrahedra, with being the number of bridging oxygen atoms that connect the tetrahedra to the rest of the network). In order to reveal the internal structure of the vibrational spectrum, the characteristics of vibrational modes in different frequency ranges are investigated using a mode-projection approach at different symmetries based on the symmetry group. In particular, the VDOS spectrum in the range from to is dominated by bending () motions related to bridging oxygen and phosphorus ( band) atoms, while the high-frequency doublet zone ( is associated mostly with the asymmetric (() and symmetric () stretching modes, and most prominent peak around (exp. ) is mainly due to asymmetric stretching vibrations supported by double-bonded oxygen atoms. The lower-frequency range below is shown to arise from a mixture of bending ( and () and rotation () modes. The scissors bending () and rotation () modes are well localized below , whereas the ( bending modes spread further into the range . The projections of the eigenmodes onto , , and species yield well-defined contributions at frequencies in striking correspondence with the positions of the Raman and infrared bands
TESS full orbital phase curve of the WASP-18b system
We present a visible-light full orbital phase curve of the transiting planet
WASP-18b measured by the TESS Mission. The phase curve includes the transit,
secondary eclipse, and sinusoidal modulations across the orbital phase shaped
by the planet's atmospheric characteristics and the star-planet gravitational
interaction. We measure the beaming (Doppler boosting) and tidal ellipsoidal
distortion phase modulations and show that the amplitudes of both agree with
theoretical expectations. We find that the light from the planet's day-side
hemisphere occulted during secondary eclipse, with a relative brightness of
ppm, is dominated by thermal emission, leading to an upper
limit on the geometric albedo in the TESS band of 0.048 (2). We also
detect the phase modulation due to the planet's atmosphere longitudinal
brightness distribution. We find that its maximum is well-aligned with the
sub-stellar point, to within 2.9 deg (2). We do not detect light from
the planet's night-side hemisphere, with an upper limit of 43 ppm (2),
which is 13 % of the day-side brightness. The low albedo, lack of atmospheric
phase shift, and inefficient heat distribution from the day to night
hemispheres that we deduce from our analysis are consistent with theoretical
expectations and similar findings for other strongly irradiated gas giant
planets. This work demonstrates the potential of TESS data for studying full
orbital phase curves of transiting systems. Finally, we complement our study by
looking for transit timing variations (TTVs) in the TESS data and combined with
previously published transit times, although we do not find a statistically
significant TTV signal.Comment: V2: Added another TESS Sector of data to the analysis, added TTV
analysis, accepted to A
The LAGUNA design study- towards giant liquid based underground detectors for neutrino physics and astrophysics and proton decay searches
The feasibility of a next generation neutrino observatory in Europe is being
considered within the LAGUNA design study. To accommodate giant neutrino
detectors and shield them from cosmic rays, a new very large underground
infrastructure is required. Seven potential candidate sites in different parts
of Europe and at several distances from CERN are being studied: Boulby (UK),
Canfranc (Spain), Fr\'ejus (France/Italy), Pyh\"asalmi (Finland),
Polkowice-Sieroszowice (Poland), Slanic (Romania) and Umbria (Italy). The
design study aims at the comprehensive and coordinated technical assessment of
each site, at a coherent cost estimation, and at a prioritization of the sites
within the summer 2010.Comment: 5 pages, contribution to the Workshop "European Strategy for Future
Neutrino Physics", CERN, Oct. 200
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