3,844 research outputs found
Building an Argument for the Use of Science Fiction in HCI Education
Science fiction literature, comics, cartoons and, in particular, audio-visual
materials, such as science fiction movies and shows, can be a valuable addition
in Human-computer interaction (HCI) Education. In this paper, we present an
overview of research relative to future directions in HCI Education, distinct
crossings of science fiction in HCI and Computer Science teaching and the
Framework for 21st Century Learning. Next, we provide examples where science
fiction can add to the future of HCI Education. In particular, we argue herein
first that science fiction, as tangible and intangible cultural artifact, can
serve as a trigger for creativity and innovation and thus, support us in
exploring the design space. Second, science fiction, as a means to analyze
yet-to-come HCI technologies, can assist us in developing an open-minded and
reflective dialogue about technological futures, thus creating a singular base
for critical thinking and problem solving. Provided that one is cognizant of
its potential and limitations, we reason that science fiction can be a
meaningful extension of selected aspects of HCI curricula and research.Comment: 6 pages, 1 table, IHSI 2019 accepted submissio
Mg II Absorber Number Density at z~0.05: Implications for Omega_DLA Evolution
An unbiased sample of 147 quasar/AGN spectra, obtained with the FOS/HST, has
been searched for intervening MgII absorbers over the redshift range 0<z<0.15.
The total redshift path searched is 18.8, with the survey being 80% complete to
a 5-sigma rest-frame equivalent width, W_r(2796), of 0.6 Ang. Main results of
this work are: [1] Four systems were found, with a mean redshift of =0.06,
yielding a redshift number density dN/dz=0.22(+0.12)(-0.09) for absorbers with
W_r(2796)>0.6 Ang. This is consistent with the value expected if these systems
do not evolve from higher redshifts (z=2.2). [2] No systems with W_r(2796)<0.6
Ang were found. It is a 2-sigma result to have a null detection of smaller
W_r(2796) systems. If this implies a turnover in the low W_r(2796) region of
the equivalent width distribution at z~0, then there is at least a 25%
reduction in the average galaxy gas cross section from z<0.2 galaxies. [3]
These systems have strong FeII absorption and are good candidates for damped
Ly-alpha absorbers DLAs (see Rao & Turnshek 2000, ApJS, 130, 1). This
translates to a redshift number density of dN/dz=0.08(+0.09)(-0.05) for DLAs at
z~0. In tandem with the data analyzed by Rao & Turnshek, these results indicate
that the redshift number density of DLAs does not evolve from z~4 to z~0. If
the HI mass function does not evolve from z~0.5 to z~0, then the cosmological
HI mass density is also deduced to not evolve from z~4 to z~0. These z~0
results for MgII absorption-selected DLAs are at odds with those based upon
21-cm emission from HI galaxies by a factor of five to six.Comment: 23 pages, 7 Figures, accepted to ApJ. Replaced version includes
additional figures and tables and substantial modifications to the tex
Mechanism of high-mobility group protein B enhancement of progesterone receptor sequence-specific DNA binding
The DNA-binding domain (DBD) of progesterone receptor (PR) is bipartite containing a zinc module core that interacts with progesterone response elements (PRE), and a short flexible carboxyl terminal extension (CTE) that interacts with the minor groove flanking the PRE. The chromosomal high-mobility group B proteins (HMGB), defined as DNA architectural proteins capable of bending DNA, also function as auxiliary factors that increase the DNA-binding affinity of PR and other steroid receptors by mechanisms that are not well defined. Here we show that the CTE of PR contains a specific binding site for HMGB that is required for stimulation of PR-PRE binding, whereas the DNA architectural properties of HMGB are dispensable. Specific PRE DNA inhibited HMGB binding to the CTE, indicating that DNA and HMGBāCTE interactions are mutually exclusive. Exogenous CTE peptide increased PR-binding affinity for PRE as did deletion of the CTE. In a PR-binding site selection assay, A/T sequences flanking the PRE were enriched by HMGB, indicating that PR DNA-binding specificity is also altered by HMGB. We conclude that a transient HMGBāCTE interaction alters a repressive conformation of the flexible CTE enabling it to bind to preferred sequences flanking the PRE
Recreation reduces tick density through fine-scale risk effects on deer space-use
Altered interactions between pathogens, their hosts and vectors have potential consequences for human disease risk. Notably, tick-borne pathogens, many of which are associated with growing deer abundance, show global increasing prevalence and pose increasing challenges for disease prevention. Human activities can largely affect the patterns of deer space-use and can therefore be potential management tools to alleviate human-wildlife conflicts. Here, we tested how deer space-use patterns are influenced by human recreational activities, and how this in turn affects the spatial distribution of the sheep tick (Ixodes ricinus), a relevant disease vector of zoonoses such as Lyme borrelioses. We compared deer dropping and questing tick density on transects near (20 m) and further away from(100 m) forest trails that were either frequently used (open for recreation) or infrequently used (closed for recreation, but used by park managers). In contrast to infrequently used trails, deer dropping density was 31% lower near (20 m) than further away from (100 m) frequently used trails. Similarly, ticks were 62% less abundant near (20 m) frequently used trails compared to further away from (100 m) these trails, while this decline in tick numbers was only 14% near infrequently used trails. The avoidance by deer of areas close to human-used trails was thus associated with a similar reduction in questing tick density near these trails. As tick abundance generally correlates to pathogen prevalence, the use of trails for recreation may reduce tick-borne disease risk for humans on and near these trails. Our study reveals an unexplored effect of human activities on ecosystems and how this knowledge could be potentially used to mitigate zoonotic disease risk
Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
Quantum computers have the potential to solve certain interesting problems
significantly faster than classical computers. To exploit the power of a
quantum computation it is necessary to perform inter-qubit operations and
generate entangled states. Spin qubits are a promising candidate for
implementing a quantum processor due to their potential for scalability and
miniaturization. However, their weak interactions with the environment, which
leads to their long coherence times, makes inter-qubit operations challenging.
We perform a controlled two-qubit operation between singlet-triplet qubits
using a dynamically decoupled sequence that maintains the two-qubit coupling
while decoupling each qubit from its fluctuating environment. Using state
tomography we measure the full density matrix of the system and determine the
concurrence and the fidelity of the generated state, providing proof of
entanglement
Recreation reduces tick density through fine-scale risk effects on deer space-use
Altered interactions between pathogens, their hosts and vectors have potential consequences for human disease risk. Notably, tick-borne pathogens, many of which are associated with growing deer abundance, show global increasing prevalence and pose increasing challenges for disease prevention. Human activities can largely affect the patterns of deer space-use and can therefore be potential management tools to alleviate human-wildlife conflicts. Here, we tested how deer space-use patterns are influenced by human recreational activities, and how this in turn affects the spatial distribution of the sheep tick (Ixodes ricinus), a relevant disease vector of zoonoses such as Lyme borrelioses. We compared deer dropping and questing tick density on transects near (20āÆm) and further away from (100āÆm) forest trails that were either frequently used (open for recreation) or infrequently used (closed for recreation, but used by park managers). In contrast to infrequently used trails, deer dropping density was 31% lower near (20āÆm) than further away from (100āÆm) frequently used trails. Similarly, ticks were 62% less abundant near (20āÆm) frequently used trails compared to further away from (100āÆm) these trails, while this decline in tick numbers was only 14% near infrequently used trails. The avoidance by deer of areas close to human-used trails was thus associated with a similar reduction in questing tick density near these trails. As tick abundance generally correlates to pathogen prevalence, the use of trails for recreation may reduce tick-borne disease risk for humans on and near these trails. Our study reveals an unexplored effect of human activities on ecosystems and how this knowledge could be potentially used to mitigate zoonotic disease risk
Heat exchange mediated by a quantum system
We consider heat transfer between two thermal reservoirs mediated by a
quantum system using the generalized quantum Langevin equation. The thermal
reservoirs are treated as ensembles of oscillators within the framework of the
Drude-Ullersma model. General expressions for the heat current and thermal
conductance are obtained for arbitrary coupling strength between the reservoirs
and the mediator and for different temperature regimes. As an application of
these results we discuss the origin of Fourier's law in a chain of large, but
finite subsystems coupled to each other by the quantum mediators. We also
address a question of anomalously large heat current between the STM tip and
substrate found in a recent experiment. The question of minimum thermal
conductivity is revisited in the framework of scaling theory as a potential
application of the developed approach.Comment: 16 pages, 6 figure
Non variability of intervening absorbers observed in the UVES spectra of the "naked-eye" GRB080319
The aim of this paper is to investigate the properties of the intervening
absorbers lying along the line of sight of Gamma-Ray Burst (GRB) 080319B
through the analysis of its optical absorption features. To this purpose, we
analyze a multi-epoch, high resolution spectroscopic observations (R=40000,
corresponding to 7.5 km/s) of the optical afterglow of GRB080319B (z=0.937),
taken with UVES at the VLT. Thanks to the rapid response mode (RRM), we
observed the afterglow just 8m:30s after the GRB onset when the magnitude was R
~ 12. This allowed us to obtain the best signal-to-noise, high resolution
spectrum of a GRB afterglow ever (S/N per resolution element ~ 50). Two further
RRM and target of opportunity observations were obtained starting 1.0 and 2.4
hours after the event, respectively. Four MgII absorption systems lying along
the line of sight to the afterglow have been detected in the redshift range 0.5
< z < 0.8, most of them showing a complex structure featuring several
components. Absorptions due to FeII, MgI and MnII are also present; they appear
in four, two and one intervening absorbers, respectively. One out of four
systems show a MgII2796 rest frame equivalent width larger than 1A. This
confirms the excess of strong MgII absorbers compared to quasars, with dn/dz =
0.9, ~ 4 times larger than the one observed along quasar lines of sight. In
addition, the analysis of multi-epoch, high-resolution spectra allowed us to
exclude a significant variability in the column density of the single
components of each absorber. Combining this result with estimates of the size
of the emitting region, we can reject the hypothesis that the difference
between GRB and QSO MgII absorbers is due to a different size of the emitting
regions.Comment: 10 pages, 15 ps figures, submitted to MNRA
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