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Interrater reliability in visual identification of interictal high-frequency oscillations on electrocorticography and scalp EEG.
High-frequency oscillations (HFOs), including ripples (Rs) and fast ripples (FRs), are promising biomarkers of epileptogenesis, but their clinical utility is limited by the lack of a standardized approach to identification. We set out to determine whether electroencephalographers experienced in HFO analysis can reliably identify and quantify interictal HFOs. Two blinded raters independently reviewed 10 intraoperative electrocorticography (ECoG) samples from epilepsy surgery cases, and 10 scalp EEG samples from epilepsy monitoring unit evaluations. HFOs were visually marked using bandpass filters (R, 80-250 Hz; FR, 250-500 Hz) with a sampling frequency of 2,000 Hz. There was agreement as to the presence or absence of epileptiform discharges (EDs), Rs, and FRs, in 17, 18, and 18 cases, respectively. Interrater reliability (IRR) was favorable with κ = 0.70, 0.80, and 0.80, respectively, and similar for ECoG and scalp electroencephalography (EEG). Furthermore, interclass correlation for rates of Rs (0.99, 95% confidence interval [CI] 0.96-0.99) and FRs (0.77, 95% CI 0.41-0.91) were superior in comparison to EDs (0.37, 95% CI -0.60 to 0.75). Our data suggest that HFO identification and quantification are reliable among experienced electroencephalographers. Our findings support the reliability of utilizing HFO data in both research and clinical arenas
MOF Derived Porous ZnO/C Nanocomposites for Efficient Dye Photodegradation
This is the author accepted manuscript. The final version is available from American Chemical Society via the DOI in this recordHomogeneously dispersed crystalline ZnO nanoparticles embedded in a porous carbon matrix were synthesized via a one-step carbonization of porous metal–organic framework MOF-5 at 800 and 1000 °C in different gas atmospheres. The resulting ZnO/C nanocomposites generally retain cubic particle morphology and high specific surface area of the precursor MOF-5. Various characterization techniques, including XRD, SEM, TEM, elemental mapping, Raman, FTIR, and XPS, confirmed that the carbonization of MOF-5 in water vapor atmosphere produced homogeneously dispersed ZnO nanoparticles confined within the functionalized porous carbon matrix. The rich oxygen-containing hydrophilic functional groups on the surface of the nanocomposite, the defects in the carbon-doped ZnO nanostructure, the crystalline ZnO nanoparticles, and the high textural properties resulted in excellent methylene blue adsorption and photodegradation performance under visible light irradiation. This simple and environmentally friendly approach can be further employed to harvest a variety of new homogeneously dispersed functional metal oxide/carbon composites for various environment and energy related applications.Engineering and Physical Sciences Research Council (EPSRC)Deutsche Forschungsgemeinschaft (German Research Council
Mott versus Slater-type metal-insulator transition in Mn-substituted Sr3Ru2O7
We present a temperature-dependent x-ray absorption (XAS) and resonant
elastic x-ray scattering (REXS) study of the metal-insulator transition (MIT)
in Sr3(Ru1-xMnx)2O7. The XAS results reveal that the MIT drives the onset of
local antiferromagnetic correlations around the Mn impurities, a precursor of
the long-range antiferromagnetism detected by REXS at T_order<T_MIT. This
establishes that the MIT is of the Mott-type (electronic correlations) as
opposed to Slater-type (magnetic order). While this behavior is induced by Mn
impurities, the (1/4,1/4,0) order exists for a wide range of Mn concentrations,
and points to an inherent instability of the parent compound.Comment: In press. A high-resolution version can be found at
http://www.phas.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/MnSRO_REXS.pd
Modelling and Simulation of Dissolution/Reprecipitation Technique for Low-Density Polyethene Using Solvent/Non-Solvent System
The global production and consumption of plastics have continued to increase. Plastics degrade slowly, causing persistent environmental pollution Developed waste plastic recycling methods are discussed in this report, with a focus on the dissolution/reprecipitation technique to restore low-density polyethene (LDPE) wastes. Aspen HYSYS is used to simulate the recycling of waste LDPE. Turpentine/petroleum ether (TURP/PetE) is chosen as solvent/non-solvent with fractions proved efficient through laboratory experiments. PetE is selected to be the non-solvent used for the precipitation of pure LDPE. The feedstock is assumed to be LDPE products containing additives such as dye. The simulation model developed estimated a pure LDPE precipitate recovery with a composition of 99% LDPE with a flowrate of 1024 tonnes per year. In addition, Aspen HYSYS could approximate a rough cost estimate that includes utility cost, installation cost and other factors. Technical challenges were eliminated, and several assumptions were taken into consideration to be able to simulate the process
Ferromagnetic Enhancement of CE-type Spin Ordering in (Pr,Ca)MnO
We present resonant soft X-ray scattering (RSXS) results from small band
width manganites (Pr,Ca)MnO, which show that the CE-type spin ordering (SO)
at the phase boundary is stabilized only below the canted antiferromagnetic
transition temperature and enhanced by ferromagnetism in the macroscopically
insulating state (FM-I). Our results reveal the fragility of the CE-type
ordering that underpins the colossal magnetoresistance (CMR) effect in this
system, as well as an unexpected cooperative interplay between FM-I and CE-type
SO which is in contrast to the competitive interplay between the ferromagnetic
metallic (FM-M) state and CE-type ordering.Comment: Accepted for publication in Phys. Rev. Let
Performance optimization of the electro-optic Q-Switching for high power laser using RTP crystal
In order to study the performance of proposal model crystal constructed from (Rubidium Titanly Phosphate, RTP) the birefringence, electric field application, optical, Influences of the most parametric on the electro-optical Q-switching operated for high power lasers are accomplished. The voltage requirements for productions Q-switching operation with electro-optical pockels-cells by means of this proposal as transversal configuration cellcrystal have been minimized from 1.900 kV to 1.808 kV for RTP cell these values were reduced in this work owing to the reduction of the thickness to length ratio of this crystal cell. The RTP crystal can be used with longitudinal electric field which is more suitable for high electro-optical modulation of high power lasers, but with extreme half-wave voltage, which is measured in this work and found to be 9.143 kV and 6.363 kV for x and y directionrespectively . Also, in this work, interpolated treatments on the measurements were applied using quarter-wave plate (Vλ/4) arrangement, which offered high improvement for using the linear of the transmission-voltage schemes to select the suitable requirement voltage for any levels switching
Physical characterisation of hemp shiv: Cell wall structure and porosity
Hemp shiv has been widely used as a plant aggregate incorporated into natural building composites such as hemp-lime due to its low thermal conductivity and high moisture buffer value. The aim of this research is to study the intrinsic physical parameters such as the porosity and cell wall structure of hemp shiv, which are responsible for the favourable thermal and hygric properties of hemp shiv. Scanning electron microscope observations of hemp shiv revealed microstructural features. A computed tomography (CT) scan improved the vizualization of pore shape and pore connectivity in three dimensions. The vessels exhibit little variation in size and there is no clear pore arrangement with a diffuse-porous distribution. The vessels are mostly solitary although some small groups of adjacent vessels exhibit shared cell walls between them. The vessels are approximately 50 to 100 μm in diameter and are surrounded by relatively thick fibre cells. These thick-walled fibres are located between the vessels with a diameter ranging from 1μm to 2μm. The pore frequency of hemp shiv (generally only measured on diffuse-porous woods) is around 20.8 vessels/mm2. The porosity of hemp shiv has been studied by a combination of mercury intrusion porosimetry (MIP) and CT scanning. Average accessible porosity of hemp shiv is 76.67 ± 2.03 % measured by MIP measurement and from 50% to 75% measured by CT, depending on the threshold and resolution
Productivity of Apple as Influenced by Rates of Nitrogen, Phosphorus and Irrigation Interval
Field experiment was conducted on an established orchard of the Kaduna State Agricultural Development Project (KADP) at Maigana during the 1998- 2001 to evaluate the effect of nitrogen, phosphorus and irrigation interval on some selected growth attributes of apple. The treatments consisted of four levels of nitrogen (0, 60, 120 and 180 kg N h -1, three levels of phosphorus (0, 22 and 44) and irrigation intervals (3, 5 and 7 days). Treatments were laid out in a split plot design with factorial combination of nitrogen and irrigation interval allocated to main plots and phosphorus assigned to sub-plots and replicated three times. The result showed that application of nitrogen up to 180 kg N ha -1 resulted to taller plants with more branches and wider canopy as well as thicker stem and heavier fruit yield. Likewise, applications of phosphorus up to 44 kg P ha -1 resulted to taller plants, more branches, wider canopy, thicker stem and heavier fruit yield. There was inconsistency in response of the parameters to irrigation interval, however the yield responded up to 7 days irrigation interval. It can be concluded that for proper apple growth, application of 180 kg N ha -1 plus 44 kg P ha -1, with 7 days irrigation interval should be adopted. Keywords: fruit yield, nitrogen, phosphorus, irrigation and nitrogen conten
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