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Meaningful change: defining the interpretability of changes in endpoints derived from interactive and mHealth technologies in healthcare and clinical research
Immersive, interactive and mHealth technologies are increasingly being used in clinical research, healthcare and rehabilitation solutions. Leveraging technology solutions to derive new and novel clinical outcome measures is important to the ongoing assessment of clinical interventions. While demonstrating statistically significant changes is an important element of intervention assessment, understanding whether changes detected reflect changes of a magnitude that are considered meaningful to patients is equally important. We describe methodologies used to determine meaningful change and recommend that these techniques are routinely included in the development and testing of clinical assessment and rehabilitation technology solutions
Electrical capability of 3D printed unpoled polyvinylidene fluoride (PVDF)/thermoplastic polyurethane (TPU) sensors combined with carbon black and barium titanate
The development of three-dimensional (3D) printed sensors attracts high interest from the smart electronic industry owing to the significant geometric freedom allowed by the printing process and the potential for bespoke composite feedstocks being imbued with specific material properties. In particular, feedstock for material extrusion (MEX) additive manufacturing by fused filament fabrication can be provided with piezoelectricity and electrical conductivity. However, piezoelectricity often requires electrical poling for activation. In this study, a candidate material containing thermoplastic polyurethane (TPU) and carbon black (CB) with conductive and flexible properties is incorporated with piezoelectric elements like polyvinylidene fluoride (PVDF) and barium titanate (BaTiO3) to assess its suitability for sensor applications without electrical poling. Texturing the surface of BaTiO3 particles and adding tetraphenylphosphonium chloride (TPPC) to the composite are evaluated as non-poling treatments to improve the sensor response. It was found that TPU and PVDF produced segregated domain structures within the printed sensors that aligned along the printing direction. Due to the effect of this preferential orientation combined with the presence of raster-raster interfaces, printed sensors exhibited significant electrical anisotropy registering greater electrical waveforms when the electrodes aligned parallel to the raster direction. An improvement of current baseline from 0.4 ÎĽA to 12 ÎĽA in the parallel direction was observed in sensors functionalised with both treatments. Similarly, when the waveform responses were measured under a standardised impact force, current amplitudes in both orientations registered a twofold increase for any impact force when both treatments were applied to the feedstock material. The results achieved within this study elucidate how composite formulations can enhance the sensor response prior to conducting electrical poling
Graphene-like nano-sheets/36° LiTaO3 surface acoustic wave hydrogen gas sensor
Presented is the material and gas sensing properties of graphene-like nano-sheets deposited on 36deg YX lithium tantalate (LiTaO3) surface acoustic wave (SAW) transducers. The graphene-like nano-sheets were characterized via scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The graphenelike nano-sheet/SAW sensors were exposed to different concentrations of hydrogen (H2) gas in a synthetic air at room temperature. The developed sensors exhibit good sensitivity towards low concentrations of H2 in ambient conditions, as well as excellent dynamic performance towards H2 at room temperature
Performance and Radiation Testing of a Low-Noise Switched Capacitor Array for the CMS Endcap Muon System.
The 16-channel, 96-cell per channel switched capacitor array ( SCA) ASIC developed at UC Davis for the cathode readout of the cathode strip chambers ( CSC) in the CMS endcap muon system is ready for production. For the final full-sized prototype, the Address Decoder was re-designed and LVDS receivers were incorporated into the chip package. Under precision testing, the chip exhibits excellent linearity within the 1V design range and very low cell-to-cell pedestal variation. Monitored samples of the production design were subjected to exposure to a 63.3 MeV proton beam. The performance of chips after exposures up to 100 krad was within tolerances of an unexposed part
A wearable headset for monitoring electromyography responses within spinal surgery
Purpose: This research examines an approach for enhancing the efficiency of spinal surgery utilising the technological capabilities and design functionalities of wearable headsets, in this case Google Glass. The aim was to improve the efficiency of the selective dorsal rhizotomy neurosurgical procedure initially through the use of Glass via an innovative approach to information design for an intraoperative monitoring display. Methods Utilising primary and secondary research methods the development of a new electromyography response display for a wearable headset was undertaken. Results: Testing proved that Glass was fit for purpose and that the new intraoperative monitor design provided an example platform for the innovative intraoperative monitoring display; however, alternative wearable headsets such as the Microsoft HoloLens could also be equally viable. Conclusion: The new display design combined with the appropriate wearable technology could greatly benefit the selective dorsal rhizotomy procedure
Relations Between Timing Features and Colors in the X-Ray Binary 4U 0614+09
We study the correlations between timing and X-ray spectral properties in the
low mass X-ray binary 4U 0614+09 using a large (265-ks) data set obtained with
the Rossi X-ray Timing Explorer. We find strong quasi-periodic oscillations
(QPOs) of the X-ray flux, like the kilohertz QPOs in many other X-ray binaries
with accreting neutron stars, with frequencies ranging from 1329 Hz down to 418
Hz and, perhaps, as low as 153 Hz. We report the highest frequency QPO yet from
any low mass X-ray binary at 1329+-4 Hz, which has implications for neutron
star structure. This QPO has a 3.5-sigma single-trial significance, for an
estimated 40 trials the significance is 2.4-sigma. Besides the kilohertz QPOs,
the Fourier power spectra show four additional components: high frequency noise
(HFN), described by a broken power-law with a break frequency between 0.7 and
45 Hz, very low frequency noise (VLFN), which is fitted as a power-law below 1
Hz, and two broad Lorentzians with centroid frequencies varying from 6 to 38 Hz
and 97 to 158 Hz, respectively. We find strong correlations between the
frequencies of the kilohertz QPOs, the frequency of the 6 to 38 Hz broad
Lorentzian, the break frequency of the HFN, the strength of both the HFN and
the VLFN and the position of the source in the hard X-ray color vs. intensity
diagram. The frequency of the 97 to 158 Hz Lorentzian does not correlate with
these parameters. We also find that the relation between power density and
break frequency of the HFN is similar to that established for black hole
candidates in the low state. We suggest that the changing mass accretion rate
is responsible for the correlated changes in all these parameters.Comment: ApJ, referee
Density saturation and the decrease of the normalised width of the multiplicity distribution in high energy pp collisions
It is experimentally observed that the width of the KNO multiplicity
distribution --or the negative binomial parameter 1/k-- for pp collisions, in
the energy region 10 to 1800 GeV, is an increasing function of the energy. We
argue that in models with parton or string saturation such trend will necessary
change: at some energy the distribution will start to become narrower. In the
framework of percolating strings, we have estimated the change to occur at an
energy of the order of 5--10 TeV.Comment: 10 pages, 4 figures, uses elsart and amsmath; comparison with some
other models was added; version accepted by PL
Efficiency of nanoparticle reinforcement using finite element analysis of titanium alloy mandible plate
Nanoparticles in the form nanotubes and nanoplatelets have been compared for von Mises stresses by using them as low-composition reinforcements in titanium alloy–based mandible plate for different compositions and orientations. A finite element model has been designed to reconstruct a fractured human mandible with a titanium alloy mandible plate. A 500 N compressive force was applied on the mandible, and stress distribution across the plate sections was analysed for aligned two-dimensional random and three-dimensional random orientations for both tubes and platelets. Carbon material as graphene has been used for tube and platelet in the form of nanotubes and nanoplatelets, respectively. Using properties of graphene as the filler in titanium alloy plate, for both nanoplatelets and nanotubes, the stresses reduced between 5% and 25% for nanoplatelets and nanotubes graphene–titanium composite plates in comparison to non-reinforced plates, at critically stressed sections. Nanotubes exhibited stress reduction of nearly 23.4% for aligned configurations, while nanoplatelets exhibited stress reduction up to 21.2% for two-dimensional and three-dinemsional random configurations in comparison to non-reinforced titanium plates. Hence, it has been suggested that nanotubes exhibited superior mechanical reinforcement potential beyond that of aligned nanoplatelets, while nanoplatelets provided enhanced mechanical reinforcements for random configurations. Therefore, for biomedical implant applications nanocomposite materials can be designed with the same dimensional form but with lower compositions of filler materials by simply manipulating the appropriate orientations
Differential Production Cross Section of Z Bosons as a Function of Transverse Momentum at sqrt{s}=1.8 TeV
We present a measurement of the transverse momentum distribution of Z bosons
produced in ppbar collisions at sqrt{s}=1.8 TeV using data collected by the D0
experiment at the Fermilab Tevatron Collider during 1994--1996. We find good
agreement between our data and a current resummation calculation. We also use
our data to extract values of the non-perturbative parameters for a particular
version of the resummation formalism, obtaining significantly more precise
values than previous determinations.Comment: 10 pages, 2 figures, submitted to Phys. Rev. Letters v2 has margin
error correcte
Search for bottom squarks in pbarp collisions at sqrt(s)=1.8 TeV
We report on a search for bottom squarks produced in pbarp collisions at
sqrt(s) = 1.8 TeV using the D0 detector at Fermilab. Bottom squarks are assumed
to be produced in pairs and to decay to the lightest supersymmetric particle
(LSP) and a b quark with branching fraction of 100%. The LSP is assumed to be
the lightest neutralino and stable. We set limits on the production cross
section as a function of bottom squark mass and LSP mass.Comment: 5 pages, Latex. submitted 3-12-1999 to PRD - Rapid Communicatio
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