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Norovirus (NoV) is a major cause of acute gastroenteritis (AGE). In this study, we investigated the genetic diversity of NoV strains identified in children under 5 years of age with AGE in four provinces of Angola. Faecal samples from 343 children were screened for NoV by an in house real-time PCR assay and genotyping was performed by partial capsid gene sequencing. NoV was detected in 17.4% (58/334) of the samples, with high detection rates in children <6 months old (19%) and in children aged 12–24 months (23%). Genotype diversity was large, as demonstrated by the 11 identified genotypes. GII.4 was the predominant genotype (20% of all NoV-positive samples), followed by GII.6 (15%), GI.3 (12%), GII.7 (10%) and by other genotypes to a lesser extent. Two GII.4 variants, New Orleans 2009 and Sydney 2012, were detected and several genetic clusters were observed for genotypes GI.3, GII.6 and GII.7. The present study shows high detection rates and genetic diversity of circulating NoV genotypes in paediatric AGE samples from Angola. This information emphasises the importance of continuous assessment of NoV burden and evolution in the target population.
The technology leading to very large aperture telescopes and their optics has progressed well in the period since 1984 and plans for many new large aperture telescopes have been made. Focal plane instrumentation continues to become more sophisticated or more efficient: multi-object capabilities, automatic instrument control and operation, and increasing use of CCDs are examples of areas to which this applies. The proportion of time devoted to observations using two-dimensional photoelectronic detectors has grown substantially at many observatories, particularly with telescopes of moderate aperture; and the use of high quantum efficiency array detectors is now being extended into the infrared spectral region. Important advances have also been made in instrumentation and techniques for ground-based high angular resolution interferometry.
The present work reports the covalent functionalization of single-walled carbon nanotubes (SWCNTs) by ferrocene derivatives with polyethyleneglycol linkers. A very clean initial sample was chosen to avoid any residual catalyst and carbon impurities. Functionalized SWCNTs (f-CNTs) are deposited on the surface of a glassy carbon electrode (GCE) and this modified electrode is used for oxidizing the cofactor NADH (dihydronicotinamide adenine dinucleotide) in the presence of diaphorase. A clear electrocatalytic effect is evidenced, which can only be attributed to the f-CNTs.
When the stoichiometric TiN was deposited directly on GaN, we obtained columnar TiN grains of 5-20 nm section which cross the whole film thickness and are rotated mostly around the  axis. The conventional epitaxial relationship is obtained and no amorphous patches are observed at the interface. The deposition of TiN on Si doped GaN layers lead to the formation of an ohmic contact, whereas we obtain a rectifying contact on p type layers.
The reported work focuses on developing antidiffusion barriers capable to increase the thermal stability of metal contacts above 700 C. In the chosen approach, such an antidiffusion barrier consists of several bilayers of materials with different crystalline structures. It has been demonstrated that an interface between such materials effectively blocks the atomic interdiffusion. In this work the following groups of materials were used as the bilayers: ZrB2 and ZrN and TaSiN and TiN. The materials were deposited by means of room temperature sputtering from elemental and compound targets in inert Ar and reactive Ar+N2 atmospheres. The structures were characterised using secondary ion mass spectroscopy depth profiling and scanning electron microscopy cross sectional imaging directly after deposition and after degradation. I-V characteristics were measured and contact resistivities were determined from the circular transmission line method.
Single crystals of Ni3AI (1 at%Ta) with a compression axis of  were subject to creep at a stress of 550 MPa and a temperature of 520 °C. Slip trace and TEM microstructural observations reveal that primary octahedral slip is responsible for the primary creep. In the secondary stage, cube cross slip (010) is operative. There is no obvious sign of inverse creep.
Mass spectrometry and calorimetry experiments on hydrogen evolution in amorphous Si:H and SiC:H nanoparticles grown by Plasma-Enhanced Chemical-Vapor Deposition (PECVD) are reported. The evolution spectra in a-Si particles are very similar to those found in films. The dynamic constants of the low-temperature peak confirm that this process is the same as in films. It is argued that the high-temperature process may not be diffusion-controlled. Both processes are exothermic, indicating that most dangling bonds recombine after H-desorption. The Hevolution in SiC occurs at higher temperatures than in Si. The process is endothermic.
Moderate wine consumption has been shown to lower cardiovascular risk. One of the mechanisms could involve the control of postprandial hyperlipaemia, a well-defined risk factor for atherosclerosis, reasonably by reducing the absorption of lipid oxidised species from the meal. The objective of the present study was to investigate whether wine consumption with the meal is able to reduce the postprandial increase in plasma lipid hydroperoxides and cholesterol oxidation products, in human subjects. In two different study sessions, twelve healthy volunteers consumed the same test meal rich in oxidised and oxidisable lipids (a double cheeseburger), with 300 ml of water (control) or with 300 ml of red wine (wine). The postprandial plasma concentration of cholesterol oxidation products was measured by GC–MS. The control meal induced a significant increase in the plasma concentration of lipid hydroperoxides and of two cholesterol oxidation products, 7-β-hydroxycholesterol and 7-ketocholesterol. The postprandial increase in lipid hydroperoxides and cholesterol oxidation products was fully prevented by wine when consumed with the meal. In conclusion, the present study provides evidence that consumption of wine with the meal could prevent the postprandial increase in plasma cholesterol oxidation products.
We have investigated the spectroscopic properties of Pr3+ ions in LiLuF4 laser host doped with 0.5% Pr3+ ions as a function of temperature. We obtained the luminescence spectra by exciting selectively the sample at 439nm into the 3P2 level and at 593nm into the 1D2 level. With excitation in the 3P2 level we obtained emission only from the 3P0 level but not from the 1D2 level at all temperatures between 24 and 300K. With excitation into the 1D2 level we observed the luminescence emitted by the same level and a strong blue up-conversion emission from the 3P0 level. We used the decay pattern inspection to assign spectral lines to specific radiative transitions and to study the dynamics of the excited ions in the crystal. Under direct excitation, the 1D2 decay curve is nonexponential at all temperatures, whereas the 3P0 decay is exponential only at low temperatures. The experimental data indicate that the 3P0 level is populated via upconversion due to mainly energy transfer.
This paper reports on the LP-MOCVD growth optimisation of GaAlN/GaN heterostructures grown on Silicon Carbide substrates for HEMT applications, and on the first device performances obtained with these structures. The critical impact of some growth parameters on the physical properties of the GaAlN/GaN epilayers has been identified and studied using High Resolution X-Ray diffraction (HR-XRD), AFM, C-V and sonogauge measurements. The SiC substrate surface preparation (both ex-situ and in-situ) and the nucleation layer growth conditions (growth temperature, thickness, composition and strain) have been found to be key steps of the GaAlN/GaN/SiC growth process. SiC substrates from different suppliers have been evaluated and their influence on the physical properties of the GaAlN/GaN HEMT structures investigated. Static characteristics of the devices such as maximum drain current Idss or pinch-off voltage have been correlated with the nucleation layer composition of the HEMT structure and the defect density of the SiC substrate. First devices measured at 10 GHz using a load pull system exhibited CW output power in excess of 2.8 W/mm for a gate length of 0.5 μm. Under static measurements, we found an Idss around 1 A/mm and a pinch-off voltage of –5 V.
This research developed two real-time PCR assays, employing high-resolution melt and allele-specific analysis to accurately genotype the F94L mutation in cattle. This mutation (g.433C > A) in the growth differentiation factor 8 or myostatin gene has recently been shown to be functionally associated with increased muscle mass and carcass yield in cattle. The F94L mutation is not, like other myostatin mutations, associated with reduced fertility and dystocia. It is therefore a candidate for introgression into other breeds to improve retail beef yield and the development of a simple and accurate test to genotype this specific mutation is warranted. Variations in the efficiency of enzyme cleavage compromised the accuracy of genotyping by published methods, potentially resulting in an overestimation of the frequency of the mutant allele. The frequency of the F94L mutation was determined by real-time PCR in 1140 animals from 15 breeds of cattle in Australia. The mutation was present in Simmental (0.8%), Piedmontese (2%), Droughtmaster (4%) and Limousin (94.2%) but not found in Salers, Angus, Poll Hereford, Hereford, Gelbvieh, Charolais, Jersey, Brahman, Holstein, Shorthorn or Maine Anjou. The low prevalence of F94L in all beef breeds except Limousin indicates the significant potential for this mutation to improve retail yield in Australian beef cattle.
In 1998, activist Marc Kasky sued Nike for alleged false advertising and unfair competition under California law. Kasky alleged that Nike made false statements in a variety of what we would usually consider non-advertising forums, including interviews and letters to the press. The Supreme Court of California permitted Kasky's suit to go forward, even though the statements were not a part of traditional paid commercial advertisements. The Supreme Court of the United States, which initially granted certiorari to review the case, dismissed the writ on June 26, 2003, leaving intact California's broad interpretation of its statute and narrow construction of the Constitutional speech protections that constrain that statute. What is typically referred to as “the Nike case” or “the Kasky case” can mean either Kasky v. Nike (as the case was originally filed) or Nike v. Kasky (when Nike appealed the lower court's judgment).
We have studied the structural and dynamical parameters
of two samples of elliptical-like-objects (ELOs)
formed in a set of self-consistent hydrodynamical simulations.
ELO stellar masses,
projected half- stellar mass radii, and stellar central
l.o.s. velocity dispersions have been found to
define a dynamical Fundamental Plane (FP),
whose physical origin we report on.
We present high resolution two dimensional velocity fields
from integral field spectroscopy along with derived rotation curves for nine low surface brightness galaxies. This is a positive step forward in terms of both data quality and number of objects studied. We fit NFW and pseudo-isothermal halo models to the observations. We find that the pseudo-isothermal halo better represents the data in most cases than the NFW halo, as the resulting concentrations are lower than would be expected for ΛCDM.
Using cosmological N-body simulations we study the
line-of-sight velocity distribution of dark matter
haloes focusing on the lowest-order even moments,
dispersion and kurtosis, and their application to
estimate the mass profiles of cosmological structures.
For each of the ten massive haloes selected from the simulation box
we determine the virial mass, concentration and the anisotropy parameter.
In order to emulate observations from each halo we choose randomly 300 particles
and project their velocities and positions along the line of sight and on the surface
of the sky, respectively. After removing interlopers we calculate the profiles of the line-of-sight
velocity moments and fit them with the solutions of the Jeans equations.
The estimates of virial mass, concentration parameter and velocity anisotropy
obtained in this way are in good agreement with the values found from the full 3D analysis.
We revisit the density profile of the galaxies cluster MS 2137-23 by
modelling strong lensing, weak lensing data and the velocity dispersion
profile of the central cD galaxy. Though we are able to model the
lensing properties with a NFW density profile, this latter model
cannot explain well the velocity dispersion nor the X-rays
properties. To accommodate all these independent constraints, one needs
to go beyond the over-simplistic assumption of spherical symmetry. The
higher mass and concentration inferred from lensing suggests that the
dark matter halo is elongated along the line of sight. The
misalignment between the projected dark matter and stellar components
also supports this scenario. Neglecting projection effects leads
to systematic discrepancies between mass estimates. We thus argue that
a fully triaxial modelling of haloes is a major concern for precision mass estimates.
Most of the orbits of the Milky Way (MW) satellite galaxies and some of the orbits
of the MW globular cluster system lie near Great Circles in the Sky.
The existence of satellites in the same orbital plane could be understood if they
were part of the same accretion event. However,
this argument cannot explain, for example, the different star formation
histories of dwarfs belonging to the same Great Circle. In this paper
we will show, using hydrodynamical cosmological simulations, that the origin of Great
Circles can be found in the filaments of cosmological structures, since satellites
accreted along the same, or close, filaments will orbit the host
roughly on the same plane.