93,584 research outputs found
Continuing the education of autistic pupils while focusing on family wellbeing during the Coronavirus Pandemic
This advice is given in the form of numbered points in no
particular order. Some will be very relevant and useful to
some autistic children and young people and their families
and others will not. It is for the reader to select those that make most sense and seem worth trying. As this document was developed at the start of the pandemic lockdown, transition back in to school /college was not then at
the top of the priority list. Supporting learners going back
into schools and colleges which may look very different
from their pre pandemic presentation is clearly an important consideration now. The first bullet point raises this
concern which is unpacked further later in the document
ac Stark shift and multiphoton-like resonances in low-frequency driven optical lattices
We suggest that Bose-Einstein condensates in optical lattices subjected to ac
forcing with a smooth envelope may provide detailed experimental access to
multiphoton-like transitions between ac-Stark-shifted Bloch bands. Such
transitions correspond to resonances described theoretically by avoided
quasienergy crossings. We show that the width of such anticrossings can be
inferred from measurements involving asymmetric pulses. We also introduce a
pulse tracking strategy for locating the particular driving amplitudes for
which resonances occur. Our numerical calculations refer to a currently
existing experimental set-up [Haller et al., PRL 104, 200403 (2010)].Comment: 5 pages, 6 figure
Instability of Rotationally Tuned Dipolar Bose-Einstein Condensates
The possibility of effectively inverting the sign of the dipole-dipole
interaction, by fast rotation of the dipole polarization, is examined within a
harmonically trapped dipolar Bose-Einstein condensate. Our analysis is based on
the stationary states in the Thomas-Fermi limit, in the corotating frame, as
well as direct numerical simulations in the Thomas-Fermi regime, explicitly
accounting for the rotating polarization. The condensate is found to be
inherently unstable due to the dynamical instability of collective modes. This
ultimately prevents the realization of robust and long-lived rotationally tuned
states. Our findings have major implications for experimentally accessing this
regime.Comment: 9 pages with 5 figure
Transparency and the Marketplace for Student Data
Student lists are commercially available for purchase on the basis of ethnicity, affluence, religion, lifestyle, awkwardness, and even a perceived or predicted need for family planning services. This study seeks to provide an understanding of the commercial marketplace for student data and the interaction with privacy law. Over several years, Fordham CLIP reviewed publicly-available sources, made public records requests to educational institutions, and collected marketing materials received by high school students. The study uncovered and documents an overall lack of transparency in the student information commercial marketplace and an absence of law to protect student information.https://ir.lawnet.fordham.edu/clip/1003/thumbnail.jp
Effect of magnetic field and temperature on the ferroelectric loop in MnWO4
The ferroelectric properties of MnWO4 single crystal have been investigated.
Despite a relatively low remanent polarization, we show that the sample is
ferroelectric. The shape of the ferroelectric loop of MnWO4 strongly depends on
magnetic field and temperature. While its dependence does not directly
correlate with the magnetocapacitance effect before the paraelectric
transition, the effect of magnetic field on the ferroelectric polarization loop
supports magnetoelectric coupling.Comment: 3 pages, 4 figures, first report on ferroelectric loop in MnWO
Loss of strength in Ni3Al at elevated temperatures
Stress decrease above the stress peak temperature (750 K) is studied in h123i single crystals of Ni3(Al, 3 at.% Hf ). Two thermally activated deformation mechanisms are evidenced on the basis of stress relaxation and strain rate change experiments. From 500 to 1070 K, the continuity of the activation volume/temperature curves reveals a single mechanism of activation enthalpy 3.8 eV/atom and volume 90 b3 at 810K with an athermal stress of 330 MPa. Over the very same temperature interval, impurity or solute diffusion towards dislocation cores is evidenced
through serrated yielding, peculiar shapes of stress–strain curves while changing the rate of straining and stress relaxation experiments. This complicates the
identification of the deformation mechanism, which is likely connected with cube glide. From 1070 to 1270 K, the high-temperature mechanism has an activation
enthalpy and volume of 4.8 eV/atom and 20 b3, respectively, at 1250 K
Towards a standardised line list for G191-B2B, and other DA type objects
We present a comprehensive analysis of the far UV spectrum of G191-B2B over
the range of 900-1700{\AA} using co-added data from the FUSE and STIS archives.
While previous identifications made by Holberg et al. (2003) are reaffirmed in
this work, it is found that many previously unidentified lines can now be
attributed to Fe, Ni, and a few lighter metals. Future work includes extending
this detailed analysis to a wider range of DA objects, in the expectation that
a more complete analysis of their atmospheres can be realised.Comment: 4 pages, 2 figures, 1 table: To appear in the proceedings of the
"18th European White Dwarf Workshop" in Krakow, Poland, 201
- …