815 research outputs found
A Quantum Computer Architecture using Nonlocal Interactions
Several authors have described the basic requirements essential to build a
scalable quantum computer. Because many physical implementation schemes for
quantum computing rely on nearest neighbor interactions, there is a hidden
quantum communication overhead to connect distant nodes of the computer. In
this paper we propose a physical solution to this problem which, together with
the key building blocks, provides a pathway to a scalable quantum architecture
using nonlocal interactions. Our solution involves the concept of a quantum bus
that acts as a refreshable entanglement resource to connect distant memory
nodes providing an architectural concept for quantum computers analogous to the
von Neumann architecture for classical computers.Comment: 4 pages, 2 figures, Slight modifications to satisfy referee, 2 new
references, modified acknowledgement. This draft to appear in PRA Rapid
Communication
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Game-Based Learning in Engineering Education
The new generation of undergraduates entering UK higher education have grown up with computer games of ever increasing sophistication. In this educational project a race game, Racing Academy, was developed to investigate how game technology and gaming communities could enhance undergraduate engineering education. The computer game embodied the principles of engineering dynamics to simulate and display in real time a car drag race in which students ‘designed’ their car by selecting an engine, tyres and gearbox from a set menu. The aim was to complete a set course in the minimum time and graphically display the dynamic performance in order to better understand the engineering system. The students and staff involved in this project provided extensive feedback on the exercise and identified the visual nature of game-based learning software as a positive feature that helped illustrate engineering dynamics. Game-based learning communities, organised around tutor groups, were seen as an excellent way of encouraging an element of competition in a small non-threatening environment while discussion forums based around Moodle provided efficient support for the large group of 160 students. Finally, learning through ‘doing’ in a game environment was proven to be a successful method of illustrating physical phenomena
Scalable quantum computation in systems with Bose-Hubbard dynamics
Several proposals for quantum computation utilize a lattice type architecture
with qubits trapped by a periodic potential. For systems undergoing many body
interactions described by the Bose-Hubbard Hamiltonian, the ground state of the
system carries number fluctuations that scale with the number of qubits. This
process degrades the initialization of the quantum computer register and can
introduce errors during error correction. In an earlier manuscript we proposed
a solution to this problem tailored to the loading of cold atoms into an
optical lattice via the Mott Insulator phase transition. It was shown that by
adding an inhomogeneity to the lattice and performing a continuous measurement,
the unit filled state suitable for a quantum computer register can be
maintained. Here, we give a more rigorous derivation of the register fidelity
in homogeneous and inhomogeneous lattices and provide evidence that the
protocol is effective in the finite temperature regime.Comment: 12 pages, 3 figures. Expanded version of manuscript submitted to the
Journal of Modern Optics. v2 corrects typesetting error in Fig.
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Racing Academy: A preliminary evaluation of an online racing car simulation game for supporting students learning of engineering
This paper reports a study which evaluates an online racing car simulation game designed to support undergraduate students learning. A game based learning community was created to support undergraduate students learning of engineering at the University of Bath. One hundred and sixty one students (146 males and 15 females), aged between 18 and 22, average age 18, participated in the study. The results indicated that there was a significant increase in the students’ knowledge of engineering. They also felt that Racing Academy was motivating. They found it enjoyable, they felt competent playing the game and they put effort into the game. The analysis of the qualitative data is ongoing and will be focussed on investigating whether the students felt that Racing Academy helped their learning. Preliminary analysis suggests that the students did feel that Racing Academy supported their learning, but that further work is needed to fully embed Racing Academy into the course
In the Pursuit of Assistance: A Team\u27s Desire to Not Let a Congenital Amputation Get in a Young Boy\u27s Way
EPICS is a service-learning design program run through Purdue University. It strives to teach students design skills through providing for individuals, communities, and organizations in the surrounding area while mirroring engineering industry standards. BME (Biomedical Engineering) is a team within EPICS that strives to serve community partners through biomedical applications. William Sevick is an elementary school student with a congenital arm amputation. William and his family have been working with the BME team for the past three years designing assistive devices with the purpose of improving his actions in daily life such as eating, playing games, and riding his bike
Scalable register initialization for quantum computing in an optical lattice
The Mott insulator state created by loading an atomic Bose-Einstein
condensate (BEC) into an optical lattice may be used as a means to prepare a
register of atomic qubits in a quantum computer. Such architecture requires a
lattice commensurately filled with atoms, which corresponds to the insulator
state only in the limit of zero inter-well tunneling. We show that a lattice
with spatial inhomogeneity created by a quadratic magnetic trapping potential
can be used to isolate a subspace in the center which is impervious to
hole-hoping. Components of the wavefunction with more than one atom in any well
can be projected out by selective measurement on a molecular photo-associative
transition. Maintaining the molecular coupling induces a quantum Zeno effect
that can sustain a commensurately filled register for the duration of a quantum
computation.Comment: 5 pages, 2 figure
The genetics of cholesteatoma study. Loss‐of‐function variants in an affected family
The aetiology of cholesteatoma remains elusive. In a recent systematic review, we discussed reports of multiple cases of cholesteatoma within families, which suggests a genetic predisposition in some cases (1). We have established a U.K. database and DNA sample bank that can be used to identify genetic variants that co‐segregate with cholesteatoma in multiply‐affected families. Recruitment to this Genetics of Cholesteatoma (GOC) Study is via the U.K. National Institute of Health Research Clinical Research Network. This preliminary communication describes the results of whole exome sequencing (WES) of DNA extracted from participants in the first fully sequenced family recruited to the study. Rare variants were filtered for co‐segregation with the cholesteatoma phenotype, and for their putative functional impact. We have identified loss of function variants in the genes EGFL8 and BTNL9 as candidate variants of interest. These are preliminary observations and the variants are of unknown significance to the disease pathology without replication or further investigation
Honey: An Advanced Antimicrobial and Wound Healing Biomaterial for Tissue Engineering Applications
Honey was used in traditional medicine to treat wounds until the advent of modern medicine. The rising global antibiotic resistance has forced the development of novel therapies as alternatives to combat infections. Consequently, honey is experiencing a resurgence in evaluation for antimicrobial and wound healing applications. A range of both Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains and biofilms, are inhibited by honey. Furthermore, susceptibility to antibiotics can be restored when used synergistically with honey. Honey’s antimicrobial activity also includes antifungal and antiviral properties, and in most varieties of honey, its activity is attributed to the enzymatic generation of hydrogen peroxide, a reactive oxygen species. Non-peroxide factors include low water activity, acidity, phenolic content, defensin-1, and methylglyoxal (Leptospermum honeys). Honey has also been widely explored as a tissue-regenerative agent. It can contribute to all stages of wound healing, and thus has been used in direct application and in dressings. The difficulty of the sustained delivery of honey’s active ingredients to the wound site has driven the development of tissue engineering approaches (e.g., electrospinning and hydrogels). This review presents the most in-depth and up-to-date comprehensive overview of honey’s antimicrobial and wound healing properties, commercial and medical uses, and its growing experimental use in tissue-engineered scaffolds
The use of trained volunteers in the response to out-of-hospital cardiac arrest – the GoodSAM Experience
In England, fewer than 1 in 10 out-of-hospital cardiac arrest victims survive to hospital discharge. This could be substantially improved by increasing bystander cardiopulmonary resuscitation and Automated External Defibrillator use.
GoodSAM is a mobile-phone, app-based system, alerting trained individuals to nearby cardiac arrests. ‘Responders’ can be notified by bystanders using the GoodSAM ‘Alerter’ function. In London, when a 999 call-handler identifies cardiac arrest, in addition to dispatching the usual professional resources, London Ambulance Service automatically activates nearby GoodSAM responders.
This article discusses the development of GoodSAM, its integration with London Ambulance Service, and the plans for future expansion
Properties of serendipitous X-ray flares discovered in XMM-Newton observations
We present the results of a search of the XMM-Newton public data archive for
stellar X-ray flares. We find eight flaring sources for which we identify 7
optical counterparts. Three of these sources have distance estimates which
allow us to determine their luminosities. Based on the decay time of the flares
and their luminosity we derive loop half-lengths of ~2-7x10^10 cm and emission
measures of ~10^54 cm^-3: these are similar to values derived for other stellar
flaring sources. One of the stars shows two flares in close succession. We
discuss the likelihood of this double event being either sympathetic or
homologous in nature. A comparison to a pair of similar flares on the Sun
suggests that homology is the more likely process driving the flare event.Comment: Accepted MNRAS, 7 page
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