4,201 research outputs found
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GDPR and E-Commerce
Creative sector companies are likely to be significantly impacted by data protection laws particularly given the fact that they are likely to store, analyse and transfer personal data as part of their day to day operations. This review looks at two general areas that will impact companies i) The new General Data Protection Regulation (‘GDPR’) – the largest overall change in data protection laws in 20 years. This is on most international companies’ agenda’s particularly given the large fines that will accompany it; and ii) Data transfers – the restrictions regarding data transfers inside and outside the EU – which may particularly be complicated post - Brexit. This specific restriction (which applied under previous laws as well as GDPR) creates complexities to global companies and could potentially be further complicated as a result of Brexit
The complex environment of the bright carbon star TX Psc as probed by spectro-astrometry
Context: Stars on the asymptotic giant branch (AGB) show broad evidence of
inhomogeneous atmospheres and circumstellar envelopes. These have been studied
by a variety of methods on various angular scales. In this paper we explore the
envelope of the well-studied carbon star TX Psc by the technique of
spectro-astrometry. Aims: We explore the potential of this method for detecting
asymmetries around AGB stars. Methods:We obtained CRIRES observations of
several CO v=1 lines near 4.6 m and HCN lines near 3 m in
2010 and 2013. These were then searched for spectro-astrometric signatures. For
the interpretation of the results, we used simple simulated observations.
Results: Several lines show significant photocentre shifts with a clear
dependence on position angle. In all cases, tilde-shaped signatures are found
where the positive and negative shifts (at PA 0deg) are associated with blue
and weaker red components of the lines. The shifts can be modelled with a
bright blob 70 mas to 210 mas south of the star with a flux of several percent
of the photospheric flux. We estimate a lower limit of the blob temperature of
1000 K. The blob may be related to a mass ejection as found for AGB stars or
red supergiants. We also consider the scenario of a companion object.
Conclusions: Although there is clear spectro-astrometric evidence of a rather
prominent structure near TX Psc, it does not seem to relate to the other
evidence of asymmetries, so no definite explanation can be given. Our data thus
underline the very complex structure of the environment of this star, but
further observations that sample the angular scales out to a few hundred
milli-arcseconds are needed to get a clearer picture
Quasi-two-dimensional Fermi surfaces of the heavy-fermion superconductor CePdIn
We report low-temperature de Haas-van Alphen (dHvA) effect measurements in
magnetic fields up to 35 T of the heavy-fermion superconductor CePdIn.
The comparison of the experimental results with band-structure calculations
implies that the 4 electrons are itinerant rather than localized. The
cyclotron masses estimated at high field are only moderately enhanced, 8 and 14
, but are substantially larger than the corresponding band masses. The
observed angular dependence of the dHvA frequencies suggests
quasi-two-dimensional Fermi surfaces in agreement with band-structure
calculations. However, the deviation from ideal two dimensionality is larger
than in CeCoIn, with which CePdIn bears a lot of similarities. This
subtle distinction accounts for the different superconducting critical
temperatures of the two compounds.Comment: accepted to Phys. Rev.
Catching the fish - Constraining stellar parameters for TX Psc using spectro-interferometric observations
Stellar parameter determination is a challenging task when dealing with
galactic giant stars. The combination of different investigation techniques has
proven to be a promising approach. We analyse archive spectra obtained with the
Short-Wavelength-Spectrometer (SWS) onboard of ISO, and new interferometric
observations from the Very Large Telescope MID-infrared Interferometric
instrument (VLTI/MIDI) of a very well studied carbon-rich giant: TX Psc. The
aim of this work is to determine stellar parameters using spectroscopy and
interferometry. The observations are used to constrain the model atmosphere,
and eventually the stellar evolutionary model in the region where the tracks
map the beginning of the carbon star sequence. Two different approaches are
used to determine stellar parameters: (i) the 'classic' interferometric
approach where the effective temperature is fixed by using the angular diameter
in the N-band (from interferometry) and the apparent bolometric magnitude; (ii)
parameters are obtained by fitting a grid of state-of-the-art hydrostatic
models to spectroscopic and interferometric observations. We find a good
agreement between the parameters of the two methods. The effective temperature
and luminosity clearly place TX Psc in the carbon-rich AGB star domain in the
H-R-diagram. Current evolutionary tracks suggest that TX Psc became a C-star
just recently, which means that the star is still in a 'quiet' phase compared
to the subsequent strong-wind regime. This is in agreement with the C/O ratio
being only slightly larger than 1.Comment: 11 pages, 9 figures, 5 table
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Start-Ed: A Model for Commercial Clinical Legal Education
This article outlines a pro bono student law clinic project focusing on providing legal assistance to startup businesses in central London. Serving more than 500 clients over this period, the clinic adapted to a number of problems by modifying its format with an emphasis on flexibility and informality. Additionally, the clinic implemented a survey in order to streamline the delivery of its advice. Data was collected from over 460 startups over a two year period between 2013 and 2015 regarding the nature of their business as well as the type of legal challenges they faced. The study revealed the primary need for basic legal advice on a few select matters including most notably company structure. In addition to collecting data on startups in London, the clinic project is presented as both a model for successful clinical education and example of how the university sector can act to boost innovation and the entrepreneurial economy
Coplanar stripline antenna design for optically detected magnetic resonance on semiconductor quantum dots
We report on the development and testing of a coplanar stripline antenna that
is designed for integration in a magneto-photoluminescence experiment to allow
coherent control of individual electron spins confined in single self-assembled
semiconductor quantum dots. We discuss the design criteria for such a structure
which is multi-functional in the sense that it serves not only as microwave
delivery but also as electrical top gate and shadow mask for the single quantum
dot spectroscopy. We present test measurements on hydrogenated amorphous
silicon, demonstrating electrically detected magnetic resonance using the
in-plane component of the oscillating magnetic field created by the coplanar
stripline antenna necessary due to the particular geometry of the quantum dot
spectroscopy. From reference measurements using a commercial electron spin
resonance setup in combination with finite element calculations simulating the
field distribution in the structure, we obtain an average magnetic field of
~0.2mT at the position where the quantum dots would be integrated into the
device. The corresponding pi-pulse time of ~0.3us fully meets the requirements
set by the high sensitivity optical spin read-out scheme developed for the
quantum dot
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