210 research outputs found
Quantum walks with encrypted data
In the setting of networked computation, data security can be a significant
concern. Here we consider the problem of allowing a server to remotely
manipulate client supplied data, in such a way that both the information
obtained by the client about the server's operation and the information
obtained by the server about the client's data are significantly limited. We
present a protocol for achieving such functionality in two closely related
models of restricted quantum computation -- the Boson sampling and quantum walk
models. Due to the limited technological requirements of the Boson scattering
model, small scale implementations of this technique are feasible with
present-day technology.Comment: 4 pages, 2 figure
âSwimming in the swampâ â inquiry into accreditation, community development, and social change
Drawing from extensive experience as community educators, this paper discusses
accreditation and its relationship to community development as informed by a
cooperative inquiry conducted by tutors. Beginning with our rationale for undertaking
the inquiry, it details our approach to community development and the
centrality of education within this. It offers a review of some literature pertinent
to both concepts before presenting findings from the inquiry itself. It concludes by
emphasising the positive features of the awarding of credits for set-learning periods
but expresses concern about difficulties with contemporary models of practice
including a degree of discordance between accreditation and education for social
change
Shoreline Dynamics Along a Developed River Mouth Barrier Island: Multi-Decadal Cycles of Erosion and Event-Driven Mitigation
Human modifications in response to erosion have altered the natural transport of sediment to and across the coastal zone, thereby potentially exacerbating the impacts of future erosive events. Using a combination of historical shoreline-change mapping, sediment sampling, three-dimensional beach surveys, and hydrodynamic modeling of nearshore and inlet processes, this study explored the feedbacks between periodic coastal erosion patterns and associated mitigation responses, focusing on the open-ocean and inner-inlet beaches of Plum Island and the Merrimack River Inlet, Massachusetts, United States. Installation of river-mouth jetties in the early 20th century stabilized the inlet, allowing residential development in northern Plum Island, but triggering successive, multi-decadal cycles of alternating beach erosion and accretion along the inner-inlet and oceanfront beaches. At a finer spatial scale, the formation and southerly migration of an erosion âhotspotâ (a setback of the high-water line by âŒ100 m) occurs regularly (every 25â40 years) in response to the refraction of northeast storm waves around the ebb-tidal delta. Growth of the delta progressively shifts the focus of storm wave energy further down-shore, replenishing updrift segments with sand through the detachment, landward migration, and shoreline-welding of swash bars. Monitoring recent hotspot migration (2008â2014) demonstrates erosion (>30,000 m3 of sand) along a 350-m section of beach in 6 months, followed by recovery, as the hotspot migrated further south. In response to these erosion cycles, local residents and governmental agencies attempted to protect shorefront properties with a variety of soft and hard structures. The latter have provided protection to some homes, but enhanced erosion elsewhere. Although the local community is in broad agreement about the need to plan for long-term coastal changes associated with sea-level rise and increased storminess, real-time responses have involved reactions mainly to short-term (<5 years) erosion threats. A collective consensus for sustainable management of this area is lacking and the development of a longer-term adaptive perspective needed for proper planning has been elusive. With a deepening understanding of multi-decadal coastal dynamics, including a characterization of the relative contributions of both nature and humans, we can be more optimistic that adaptations beyond mere reactions to shoreline change are achievable
Laser Interferometer Space Antenna
Following the selection of The Gravitational Universe by ESA, and the
successful flight of LISA Pathfinder, the LISA Consortium now proposes a 4 year
mission in response to ESA's call for missions for L3. The observatory will be
based on three arms with six active laser links, between three identical
spacecraft in a triangular formation separated by 2.5 million km.
LISA is an all-sky monitor and will offer a wide view of a dynamic cosmos
using Gravitational Waves as new and unique messengers to unveil The
Gravitational Universe. It provides the closest ever view of the infant
Universe at TeV energy scales, has known sources in the form of verification
binaries in the Milky Way, and can probe the entire Universe, from its smallest
scales near the horizons of black holes, all the way to cosmological scales.
The LISA mission will scan the entire sky as it follows behind the Earth in its
orbit, obtaining both polarisations of the Gravitational Waves simultaneously,
and will measure source parameters with astrophysically relevant sensitivity in
a band from below Hz to above Hz.Comment: Submitted to ESA on January 13th in response to the call for missions
for the L3 slot in the Cosmic Vision Programm
Can Simply Answering Research Questions Change Behaviour? Systematic Review and Meta Analyses of Brief Alcohol Intervention Trials
BACKGROUND: Participant reports of their own behaviour are critical for the provision and evaluation of behavioural interventions. Recent developments in brief alcohol intervention trials provide an opportunity to evaluate longstanding concerns that answering questions on behaviour as part of research assessments may inadvertently influence it and produce bias. The study objective was to evaluate the size and nature of effects observed in randomized manipulations of the effects of answering questions on drinking behaviour in brief intervention trials. METHODOLOGY/PRINCIPAL FINDINGS: Multiple methods were used to identify primary studies. Between-group differences in total weekly alcohol consumption, quantity per drinking day and AUDIT scores were evaluated in random effects meta-analyses. Ten trials were included in this review, of which two did not provide findings for quantitative study, in which three outcomes were evaluated. Between-group differences were of the magnitude of 13.7 (-0.17 to 27.6) grams of alcohol per week (approximately 1.5 U.K. units or 1 standard U.S. drink) and 1 point (0.1 to 1.9) in AUDIT score. There was no difference in quantity per drinking day. CONCLUSIONS/SIGNIFICANCE: Answering questions on drinking in brief intervention trials appears to alter subsequent self-reported behaviour. This potentially generates bias by exposing non-intervention control groups to an integral component of the intervention. The effects of brief alcohol interventions may thus have been consistently under-estimated. These findings are relevant to evaluations of any interventions to alter behaviours which involve participant self-report
2019 ESC/EAS guidelines for the management of dyslipidaemias : Lipid modification to reduce cardiovascular risk
Correction: Volume: 292 Pages: 160-162 DOI: 10.1016/j.atherosclerosis.2019.11.020 Published: JAN 2020Peer reviewe
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