843 research outputs found
Conductivity of boules of single crystal sodium beta-alumina
The ionic and electrochemical polarization characteristics of two boules of single crystal sodium beta-alumina (Na2O.8Al2O3), 2 cm in diameter, were investigated over the range of 25 to 300 C using 2- and 4-probe ac and dc techniques with reversible and ion-blocking electrodes. Textural (or internal) polarization at 27 C was present only in boule 1 which cleaved easily. Interfacial polarization, using solid sodium electrodes, was present at 27 C in the 2-probe conductivities for both boules. Cleaning with liquid sodium at 300 C reduced its magnitude, but some interfacial polarization was still present in the 2-probe conductivities for boule 2 below about 140 C. Above 140 C, with liquid sodium electrodes, the 2-probe conductivities, essentially polarization-free, were given by KT = 3300 exp(-3650/RT). The conductivity of boule 2 at 180 C remained essentially constant with increasing current density up to about 140 milliamps per square centimeter
Visual art inspired by the collective feeding behavior of sand-bubbler crabs
Sand--bubblers are crabs of the genera Dotilla and Scopimera which are known
to produce remarkable patterns and structures at tropical beaches. From these
pattern-making abilities, we may draw inspiration for digital visual art. A
simple mathematical model is proposed and an algorithm is designed that may
create such sand-bubbler patterns artificially. In addition, design parameters
to modify the patterns are identified and analyzed by computational aesthetic
measures. Finally, an extension of the algorithm is discussed that may enable
controlling and guiding generative evolution of the art-making process
Recommended from our members
Personalized versus standardized dosing strategies for the treatment of childhood amblyopia: study protocol for a randomized controlled trial
Background: Amblyopia is the commonest visual disorder of childhood in Western societies, affecting, predominantly,
spatial visual function. Treatment typically requires a period of refractive correction (‘optical treatment’) followed by occlusion: covering the nonamblyopic eye with a fabric patch for varying daily durations. Recent studies have provided insight into the optimal amount of patching (‘dose’), leading to the adoption of standardized dosing strategies, which, though an advance on previous ad-hoc regimens, take little account of individual patient characteristics. This trial compares the effectiveness of a standardized dosing strategy (that is, a fixed daily occlusion dose based on disease severity) with a personalized dosing strategy (derived from known treatment dose-response functions), in which an initially prescribed occlusion dose is modulated, in a systematic manner, dependent on treatment compliance.
Methods/design: A total of 120 children aged between 3 and 8 years of age diagnosed with amblyopia in association with either anisometropia or strabismus, or both, will be randomized to receive either a standardized or a personalized occlusion dose regimen. To avoid confounding by the known benefits of refractive correction, participants will not be randomized until they have completed an optical treatment phase. The primary study objective is to determine whether, at trial endpoint, participants receiving a personalized dosing strategy require fewer hours of occlusion than those in receipt of a standardized dosing strategy. Secondary objectives are to quantify the relationship between
observed changes in visual acuity (logMAR, logarithm of the Minimum Angle of Resolution) with age, amblyopia type, and severity of amblyopic visual acuity deficit.
Discussion: This is the first randomized controlled trial of occlusion therapy for amblyopia to compare a treatment arm representative of current best practice with an arm representative of an entirely novel treatment regimen based on statistical modelling of previous trial outcome data. Should the personalized dosing strategy demonstrate superiority over the standardized dosing strategy, then its adoption into routine practice could bring practical benefits in reducing the duration of treatment needed to achieve an optimal outcome
Examining and describing professional development and continuing education in the personal training and fitness industry : sites and issues of disconnect
The following phenomenologically oriented study examines and describes the
relevance and effectiveness of professional development and continuing education
programs for real-world situations of personal trainers. The participants were personal
trainers, facility managers, and persons involved in the accreditation process. Data
collection took place in 3 phases. The first phase consisted of the participants completing
the PUMP Questionnaire, followed by focus groups with personal trainers and interviews
with managers. The study's 3 data sets required reduction via a content analysis by
question, content analysis by existential categories, and further thematic analysis using
the lived relation existential dimension. The discussion contains the salient sites and
issues of disconnect between clients, personal trainers, and facility managers and how
they might affect the personal training experience. The intergenerational disconnect
emphasized between Boomers as clients and Millennials as personal trainers requires
further exploration and dialogue and underscores the need for different approaches to
content and delivery of professional development and continuing education experiences
for personal trainers and managers of fitness facilities
Othering others: Right-wing populism in UK media discourse on “new” immigration
Right wing populism is on the rise. Through the use of othering, right-wing groups delimit their own identities while excluding others. The purpose of this chapter is to shed light on how European mediated public spheres (such as reader responses to media discourse) constitute an important domain of identity articulation and struggle through the discursive construction of the ‘Other’. In this case, the others come from the Central and Eastern European countries that are perceived as newcomers to Western Europe due to the consecutive enlargements of the European Union. Specifically, this chapter provides an in-depth analysis of 236 reader comments responding to one online article from The Telegraph that discusses “new” immigration from Bulgaria and Romania to the U.K., a result of the lifting of work restrictions in 2014. Applying methods of Conversation Analysis and critical discourse analysis (including relevant EU history and background), we expose numerous levels of othering in the data (e.g. othering those who disagree with right-wing political views, othering the EU, othering non-native speakers, othering migrants/Roma) and demonstrate the various strategies that are used to accomplish this (e.g. argumentation strategies, perspectivization, etc.)
Recommended from our members
Compliance with occlusion therapy for childhood amblyopia
Purpose. Explore compliance with occlusion treatment of amblyopia in the Monitored and Randomized Occlusion Treatment of Amblyopia Studies (MOTAS and ROTAS), using objective monitoring.
Methods. Both studies had a three-phase protocol: initial assessment, refractive adaptation, and occlusion. In the occlusion phase, participants were instructed to dose for 6 hours/day (MOTAS) or randomized to 6 or 12 hour/day (ROTAS). Dose was monitored continuously using an occlusion dose monitor (ODM).
Results. One hundred and fifty-two patients (71 male, 81 female; 122 Caucasian, 30 non-Caucasian) of mean ± SD age 68 ± 18 months participated. Amblyopia was defined as an interocular acuity difference of at least 0.1 logMAR and was associated with anisometropia in 50, strabismus in 44, and both (mixed) in 58. Median duration of occlusion was 99 days (interquartile range 72 days). Mean compliance was 44%, mean proportion of days with no patch worn was 42%. Compliance was lower (39%) on weekends compared with weekdays (46%, P = 0.04), as was the likelihood of dosing at all (52% vs. 60%, P = 0.028). Compliance was lower when attendance was less frequent (P < 0.001) and with prolonged treatment duration (P < 0.001). Age, sex, amblyopia type, and severity were not associated with compliance. Mixture modeling suggested three subpopulations of patch day doses: less than 30 minutes; doses that achieve 30% to 80% compliance; and doses that achieve around 100% compliance.
Conclusions. This study shows that compliance with patching treatment averages less than 50% and is influenced by several factors. A greater understanding of these influences should improve treatment outcome. (ClinicalTrials.gov number, NCT00274664.
VAST: An ASKAP Survey for Variables and Slow Transients
The Australian Square Kilometre Array Pathfinder (ASKAP) will give us an
unprecedented opportunity to investigate the transient sky at radio
wavelengths. In this paper we present VAST, an ASKAP survey for Variables and
Slow Transients. VAST will exploit the wide-field survey capabilities of ASKAP
to enable the discovery and investigation of variable and transient phenomena
from the local to the cosmological, including flare stars, intermittent
pulsars, X-ray binaries, magnetars, extreme scattering events, interstellar
scintillation, radio supernovae and orphan afterglows of gamma ray bursts. In
addition, it will allow us to probe unexplored regions of parameter space where
new classes of transient sources may be detected. In this paper we review the
known radio transient and variable populations and the current results from
blind radio surveys. We outline a comprehensive program based on a multi-tiered
survey strategy to characterise the radio transient sky through detection and
monitoring of transient and variable sources on the ASKAP imaging timescales of
five seconds and greater. We also present an analysis of the expected source
populations that we will be able to detect with VAST.Comment: 29 pages, 8 figures. Submitted for publication in Pub. Astron. Soc.
Australi
- …
