27,905 research outputs found
UML Deficiencies from the perspective of Automatic Performance Model Generation
A discussion surrounding the use of UML for distributed system design
Nanomolecular detection of human influenza virus type A using reverse transcription loop-mediated isothermal amplification assisted with rod-shaped gold nanoparticles
Reverse transcription loop-mediated isothermal amplification (RT-LAMP) and rod-shaped gold nanoparticles (gold nanorods; GNRs) were employed for nanomolecular detection of human influenza virus type A RNA. After cDNA synthesis from the RNA, the primers targeting the M protein gene were used for LAMP amplification. A blue shift from red to purple from the GNR inserting into the LAMP-DNAs can be seen by the naked eye. Transmission electron microscopy revealed the formation GNR aggregates due to their interactions with LAMP DNA. One pg RNA (10-3 dilution of the viral cDNA) was detected using this colorimetric test. The nanomolecular test showed 100% sensitivity and 95.8% specificity in comparison to results by RT-PCR. Also, the test indicated 100% sensitivity and 100% specificity in comparison to results by RT-LAMP. The described nanomolecular test could detect human influenza virus type A RNA in nearly 1 hour. This journal is © the Partner Organisations 2014
Communications software performance prediction
Software development can be costly and it is important that confidence in a software system be established as early as possible in the design process. Where the software supports communication services, it is essential that the resultant system will operate within certain performance constraints (e.g. response time). This paper gives an overview of work in progress on a collaborative project sponsored by BT which aims to offer performance predictions at an early stage in the software design process. The Permabase architecture enables object-oriented software designs to be combined with descriptions of the network configuration and workload as a basis for the input to a simulation model which can predict aspects of the performance of the system. The prototype implementation of the architecture uses a combination of linked design and simulation tools
Gravitational waves from three-dimensional core-collapse supernova models: The impact of moderate progenitor rotation
We present predictions for the gravitational-wave (GW) emission of
three-dimensional supernova (SN) simulations performed for a 15 solar-mass
progenitor with the Prometheus-Vertex code using energy-dependent, three-flavor
neutrino transport. The progenitor adopted from stellar evolution calculations
including magnetic fields had a fairly low specific angular momentum (j_Fe <~
10^{15} cm^2/s) in the iron core (central angular velocity ~0.2 rad/s), which
we compared to simulations without rotation and with artificially enhanced
rotation (j_Fe <~ 2*10^{16} cm^2/s; central angular velocity ~0.5 rad/s). Our
results confirm that the time-domain GW signals of SNe are stochastic, but
possess deterministic components with characteristic patterns at low
frequencies (<~200 Hz), caused by mass motions due to the standing accretion
shock instability (SASI), and at high frequencies, associated with gravity-mode
oscillations in the surface layer of the proto-neutron star (PNS). Non-radial
mass motions in the post-shock layer as well as PNS convection are important
triggers of GW emission, whose amplitude scales with the power of the
hydrodynamic flows. There is no monotonic increase of the GW amplitude with
rotation, but a clear correlation with the strength of SASI activity. Our
slowly rotating model is a fainter GW emitter than the non-rotating model
because of weaker SASI activity and damped convection in the post-shock layer
and PNS. In contrast, the faster rotating model exhibits a powerful SASI spiral
mode during its transition to explosion, producing the highest GW amplitudes
with a distinctive drift of the low-frequency emission peak from ~80-100 Hz to
~40-50 Hz. This migration signifies shock expansion, whereas non-exploding
models are discriminated by the opposite trend.Comment: Added new figure, figure 9. Updated figure 9, now figure 10. Modified
the discussion of the proto-neutron star convection. Added a figure showing
the average rotation rate as a function of radius. Added a section discussing
where the low-frequency gravitational waves are generated, this information
is visualized in figure 9. We also made some minor changes to the text and
selected plot
Integral analysis of laminar indirect free convection boundary layers with weak blowing for Schmidt no. ~ 1
Laminar natural convection at unity Schmidt number over a horizontal surface
with a weak normal velocity at the wall is studied using an integral analysis.
To characterise the strength of the blowing, we define a non-dimensional
parameter called the blowing parameter. After benchmarking with the no blowing
case, the effect of the blowing parameter on boundary layer thickness, velocity
and concentration profiles is obtained. Weak blowing is seen to increase the
wall shear stress. For blowing parameters greater than unity, the diffusional
flux at the wall becomes negligible and the flux is almost entirely due to the
blowing.Comment: 10 pages, published in International Communications in heat and mass
transfer,Vol31,No8, 2004, pp 1199 -120
A Systematic Review and Meta-Analysis Evaluating Antibiotic Prophylaxis in Dental Implants and Extraction Procedures
Background and objectives: The use of antibiotic prophylaxis in extraction and implant dentistry is still controversial, with varying opinions regarding their necessity. The overuse of antibiotics has led to widespread antimicrobial resistance and the emergence of multi drug resistant strains of bacteria. The main aim of this work was to determine whether there is a genuine need for antibiotic prophylaxis in two common dental procedures; dental implants and tooth extractions. Methods: Electronic searches were conducted across databases such as Cochrane Register of Controlled Trials, the UK National Health Service, Centre for reviews, Science Direct, PubMed and the British Dental Journal to identify clinical trials of either dental implants or tooth extractions, whereby the independent variable was systemic prophylactic antibiotics used as part of treatment in order to prevent postoperative complications such as implant failure or infection. Primary outcomes of interest were implant failure, and postoperative infections which include systemic bacteraemia and localised infections. The secondary outcome of interest was adverse events due to antibiotics. The Critical Appraisal Skills Programme tool was used to assess the risk of bias, extract outcomes of interest and to identify studies for inclusion in the meta-analysis. Results: Seven randomised clinical trials (RCTs) were included in the final review comprising n = 1368 patients requiring either tooth extraction(s) or dental implant(s). No statistically significant evidence was found to support the routine use of prophylactic antibiotics in reducing the risk of implant failure (p = 0.09, RR 0.43; 95% CI 0.16⁻1.14) or post-operative complications (p = 0.47, RR: 0.74; 95% CI 0.34⁻1.65) under normal conditions. Approximately 33 patients undergoing dental implant surgery need to receive antibiotics in order to prevent one implant failure from occurring. Conclusions: There is little conclusive evidence to suggest the routine use of antibiotic prophylaxis for third molar extractive surgery in healthy young adults. There was no statistical evidence for adverse events experienced for antibiotics vs. placebo. Based on our analysis, even if financially feasible, clinicians must carefully consider the appropriate use of antibiotics in dental implants and extraction procedures due to the risk of allergic reactions and the development of microbial drug resistance.Published versio
The breaking of the flavour permutational symmetry: Mass textures and the CKM matrix
Different ansaetze for the breaking of the flavour permutational symmetry
according to S(3)L X S(3)R in S(2)L X S(2) give different Hermitian mass
matrices of the same modified Fritzsch type, which differ in the symmetry
breaking pattern. In this work we obtain a clear and precise indication on the
preferred symmetry breaking scheme from a fit of the predicted theoretical Vckm
to the experimentally determined absolute values of the elements of the CKM
matrix. The preferred scheme leads to simple mass textures and allows us to
compute the CKM mixing matrix, the Jarlskog invariant J, and the three inner
angles of the unitarity triangle in terms of four quark mass ratios and only
one free parameter: the CP violating phase Phi. Excellent agreement with the
experimentally determined absolute values of the entries in the CKM matrix is
obtained for Phi = 90 deg. The corresponding computed values of the Jarlskog
invariant and the inner angles are J = 3.00 X 10^-5, alpha= 84 deg, beta= 24
deg and gamma =72 deg in very good agreement with current data on CP violation
in the neutral kaon-antikaon system and oscillations in the B-Bbar system.Comment: 21 pages, 1 fig. Content enlarged, references added and typos
corrected. To be published in Phys Rev
- …