1,997 research outputs found
Sub 1GHz M2M communications standardization: The advancement in white space utilization for enhancing the energy efficiency
Energy efficiency of machine to machine (M2M) communications terminals is one of the major design goals of M2M networks, resulting from anticipated over 50 billion M2M communications devices to be deployed into the networks by 2020 [1]. The stakeholders in the M2M communications have observed that it will be environmental and economic catastrophic to deploy M2M communications devices without solving the energy inefficiencies associated with wireless devices that are expected to be used for M2M communications. In view of the aforementioned energy challenge, sub 1GHz spectra have provided enormous opportunities that can be energy efficient, cost effective and coverage efficiency which can be utilized for M2M communications. This work will evaluate the energy efficiency benefits of optimized Sub 1GHz spectra for M2M communications
Qualitative evaluation of a practice-based experience pilot program for master of pharmacy students in Scotland
Objective. To determine the views of pharmacists in central Scotland regarding experiential education for MPharm students. Methods. A thematic analysis was completed by Ms. Gillian Hendry and Dr. Sally Wiggins of interviews conducted with ten practicing pharmacists paired with first-year master of pharmacy (MPharm) students during the 2011-2012 academic year. Relevant comments from the interviews were manually sorted in a Microsoft Excel spreadsheet to bring similarly themed material together to facilitate the identification and naming of recurring themes and subthemes. Results. The pharmacists were unanimous in their opinion that experiential education was valuable for MPharm students and, in particular, that it helped students to develop self-confidence. The pharmacists derived personal satisfaction in developing mentor/mentee relationships with students. They also recognized the value that students provided to the workforce as well as the educational value to themselves in supervising students. The participantsâ primary dissatisfaction was that the pharmacy workflow limited the time they could spend mentoring students. Conclusion. The results provide guidance to the academic community and the pharmacy practice community in the United Kingdom (UK) regarding the design and integration of experiential education courses in MPharm degree programs
Hormonal contraceptive methods and risk of HIV acquisition in women : a systematic review of epidemiological evidence
Peer reviewedPublisher PD
Modelling, simulation and experimental validation of nonlinear dynamic interactions in an aramid rope system
Vibration phenomena taking place in lifting and hoist installations may influence the dynamic performance of their components. For example, in an elevator system they may affect ride quality of a lift car. Lateral and longitudinal vibrations of suspension ropes and compensating cables may result in an adverse dynamic behaviour of the entire installation. Thus, there is a need to develop reliable mathematical and computer simulation models to predict the dynamic behaviour of suspension rope and compensating cable systems. The aim of this paper is to develop a model of an aramid suspension rope system in order to predict nonlinear modal interactions taking place in the installation. A laboratory model comprising an aramid suspension rope, a sheave/pulley assembly and a rigid suspended mass has been studied. Experimental tests have been conducted to identify modal nonlinear couplings in the system. The dynamic behaviour of the model has been described by a set of nonlinear partial differential equations. The equations have been solved numerically. The numerical results have been validated by experimental tests. It has been shown that the nonlinear couplings may lead to adverse modal interactions in the system
Atomic Spectral Features During Thermonuclear Flashes on Neutron Stars
The gravitational redshift measured by Cottam, Paerels and Mendez for the
neutron star (NS) in the low-mass X-ray binary EXO 0748-676 depends on the
identification of an absorption line during a type I burst as the H
line from hydrogenic Fe. We show that Fe is present above the photosphere as
long as during the burst. In
this limit, the total Fe column is for incident material of solar abundances and only depends on the
nuclear physics of the proton spallation. The Fe destruction creates many heavy
elements with which may imprint photo-ionization edges on the NS spectra
during a radius expansion event or in a burst cooling tail. Detecting these
features in concert with those from Fe would confirm a redshift measurement. We
also begin to address the radiative transfer problem, and find that a
concentrated Fe layer with and column (depending on the line depth) above the hotter
continuum photosphere is required to create the H line of the observed
strength. This estimate must be refined by considerations of non-LTE effects as
well as resonant line transport. Until these are carried out, we cannot say
whether the Fe column from accretion and spallation is in conflict with the
observations. We also show that hydrogenic Fe might remain in the photosphere
due to radiative levitation from the high burst flux.Comment: Substantially revised version, to appear in Ap J Letter
Managing the delivery of iconic football stadiums in England
The English football premier league has become the most
popular sports league in the world; with ardent fans and
audiences all over the world. The potential business
opportunities that this growth holds have therefore
attracted investors who are keen to buy shares in the
clubs and sign up the best footballers that money can buy.
Underpinning the growth in all of the premier league clubs
is a desire to make a distinct statement of identity as part
of a competitive strategy. One way to achieve this is
through the design and construction of iconic football
stadiums. This paper explores the specific project
management challenges associated with delivery of iconic
football stadiums in England and draws lessons for the
management of similar iconic infrastructure projects. A
study of project management best practice and some case
studies shows that key issues which are common to these
projects are centred on design management; choice of
procurement route; client management; and stakeholder
expectation management. These issues are not necessarily
unique to the project management of iconic football
stadiums but are amplified by the context of these
projects. The emphasis on iconic status in a competitive
market also means that stadium projects should be
conceived and delivered in the context of other strategic
projects which should be clearly understood by the project
management team
Broad-band X-Ray Spectra of the Black Hole Candidate GRO J1655-40
We present broad-band (2 keV to 2 MeV) X-ray spectra of GRO J1655-40, a
luminous X-ray transient and occasional source of relativistic radio jets,
obtained with RXTE and OSSE. In one observation, the luminosity is found to be
18% of the Eddington limit, which is one of the highest luminosities ever
observed from GRO J1655-40. For this observation, we find that an adequate fit
is obtained when a broad iron line and a reflection component are added to a
model consisting of a power-law plus a soft excess component. The 95%
confidence lower limit on the rms line width is 0.86 keV. The power-law
component has a photon index of 2.72 and extends to at least 800 keV without a
cutoff. After this observation, a significant drop in the (5-12 keV)/(1.5-5
keV) hardness ratio occurred on a timescale less than 2 hours. From an RXTE
observation of GRO J1655-40 made after the hardness transition, we find that
the power-law index is harder (2.415 +/- 0.011), the flux of the power-law
component is lower, and the total luminosity is 10% of the Eddington limit. The
change in the power-law component is consistent with the correlation between
the spectral index and power-law flux previously reported for GRO J1655-40.Comment: 20 pages, 5 figures, Accepted for publication in the Astrophysical
Journa
Immunogenicity and safety of three consecutive production lots of the non replicating smallpox vaccine MVA: A randomised, double blind, placebo controlled phase III trial
<div><p>Background</p><p>Modified Vaccinia Ankara (MVA) is a live, viral vaccine under advanced development as a non-replicating smallpox vaccine. A randomised, double-blind, placebo-controlled phase III clinical trial was conducted to demonstrate the humoral immunogenic equivalence of three consecutively manufactured MVA production lots, and to confirm the safety and tolerability of MVA focusing on cardiac readouts.</p><p>Methods</p><p>The trial was conducted at 34 sites in the US. Vaccinia-naïve adults aged 18-40 years were randomly allocated to one of four groups using a 1:1:1:1 randomization scheme. Subjects received either two MVA injections from three consecutive lots (Groups 1-3), or two placebo injections (Group 4), four weeks apart. Everyone except personnel involved in vaccine handling and administration was blinded to treatment. Safety assessment focused on cardiac monitoring throughout the trial. Vaccinia-specific antibody titers were measured using a Plaque Reduction Neutralization Test (PRNT) and an Enzyme-Linked Immunosorbent Assay (ELISA). The primary immunogenicity endpoint was Geometric Mean Titers (GMTs) after two MVA vaccinations measured by PRNT at trial visit 4. This trial is registered with ClinicalTrials.gov, number NCT01144637.</p><p>Results</p><p>Between March 2013 and May 2014, 4005 subjects were enrolled and received at least one injection of MVA (n = 3003) or placebo (n = 1002). The three MVA lots induced equivalent antibody titers two weeks after the second vaccination, with seroconversion rates of 99·8% (PRNT) and 99·7% (ELISA). Overall, 180 (6·0%) subjects receiving MVA and 29 (2·9%) subjects in the placebo group reported at least one unsolicited Adverse Event (AE) that was considered trial-related. Vaccination was well tolerated without significant safety concerns, particularly regarding cardiac assessment.</p><p>Conclusions</p><p>The neutralizing and total antibody titers induced by each of the three lots were equivalent. No significant safety concerns emerged in this healthy trial population, especially regarding cardiac safety, thus confirming the excellent safety and tolerability profile of MVA.</p><p>Trial registration</p><p>ClinicalTrials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT01144637" target="_blank">NCT01144637</a></p></div
Integrated modelling for economic valuation of the role of forests and woodlands in drinking water provision to two African cities
Rapidly growing economies often have high population growth, resulting in agricultural expansion in rural areas and increased water demand in urban areas. Conversion of forests and woodlands to agriculture may threaten safe and reliable water supply in cities. This study assesses the regulating functions and economic values of forests and woodlands in meeting the water needs of two major cities in Tanzania and proposes an integrated modelling approach with a scenario-based analysis to estimate costs of water supply avoided by forest conservation. We use the process-based hydrological Soil and Water Assessment Tool (SWAT) to simulate the role of woody habitats in the regulation of hydrological flow and sediment control. We find that the forests and woodlands play a significant role in regulating sediment load in rivers and reducing peak flows, with implications for the water supply from the Ruvu River to Dar es Salaam and Morogoro. A cost-based value assessment under water treatment works conditions up to 2016 suggests that water supply failure due to deforestation would cost Dar es Salaam USD 4.6-17.6 million per year and Morogoro USD 308 thousand per year. Stronger enforcement of forest and woodland protection in Tanzania must balance water policy objectives and food security
Improving the Segmentation of Scanning Probe Microscope Images using Convolutional Neural Networks
A wide range of techniques can be considered for segmentation of images of
nanostructured surfaces. Manually segmenting these images is time-consuming and
results in a user-dependent segmentation bias, while there is currently no
consensus on the best automated segmentation methods for particular techniques,
image classes, and samples. Any image segmentation approach must minimise the
noise in the images to ensure accurate and meaningful statistical analysis can
be carried out. Here we develop protocols for the segmentation of images of 2D
assemblies of gold nanoparticles formed on silicon surfaces via deposition from
an organic solvent. The evaporation of the solvent drives far-from-equilibrium
self-organisation of the particles, producing a wide variety of nano- and
micro-structured patterns. We show that a segmentation strategy using the U-Net
convolutional neural network outperforms traditional automated approaches and
has particular potential in the processing of images of nanostructured systems.Comment: 21 pages, 10 figure
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