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The relationship between epilepsy and the presence of visceral larva migrans caused by Toxocara canis in Mexican children remains uncertain; however, this relationship needs to be elucidated because these parasite larvae can invade the human central nervous system. Accordingly, this study aimed to determine the frequency and specificity of anti-T. canis antibodies in the sera of children with epilepsy to determine the relationship between this parasite and epilepsy. The sera samples of 214 children were examined: 111 children diagnosed with epilepsy and 103 clinically healthy children without neurological disorders. In the sera of each group, the presence and specificity of anti-T. canis and anti-Ascaris lumbricoides antibodies, as well as the cross-reactivity between them, were assessed using enzyme-linked immunosorbent assay and Western blotting analysis. Among the children with epilepsy, 25.2% exhibited seropositivity to T. canis. Cross-reactivity against the A. lumbricoides antigen was present in 46.8% of the children with epilepsy, whereas 11.7% of the children with epilepsy and anti-T. canis antibodies did not exhibit cross-reactivity against this antigen. The Western blotting analysis of the sera from the children with epilepsy demonstrated the presence of T. canis proteins, with molecular weights of 24, 35, 55, 70, 120 and 210 kDa, and A lumbricoides proteins with molecular weights of 70, 80 and 110 kDa. Our results revealed the presence of anti-T. canis antibodies in the children with epilepsy; furthermore, cross-reactivity tests with A. lumbricoides showed the importance of the presence of anti-T. canis antibodies in revealing the relationship between this parasite and epilepsy in children.
The physical processes taking place in massive stars during their life and death are highly dependent on the metallicity (Z) of their parent cloud. Observations of these stars in low-Z nearby galaxies are crucial to understand these processes. IC1613 is the nearest Local Group galaxy with ongoing star formation and O-abundance lower than the SMC, although UV spectroscopy suggests it is not so metal poor. We performed a spectral analysis of early B-type stars in the galaxy, obtaining physical parameters and abundances. Our results confirm the low O-abundance of IC1613.
Recent studies of WNh stars at the cores of young massive clusters have challenged the previously accepted upper stellar mass limit (~150 M⊙), suggesting some of these objects may have initial masses as high as 300 M⊙. We investigated the possible existence of observed stars above ~150 M⊙ by i) examining the nature and stellar properties of VFTS 682, a recently identified WNh5 very massive star, and ii) studying the uncertainties in the luminosity estimates of R136’s core stars due to crowding. Our spectroscopic analysis reveals that the most massive members of R136 and VFTS 682 are very similar and our K-band photometric study of R136’s core stars shows that the measurements seem to display higher uncertainties than previous studies suggested; moreover, for the most massive stars in the cluster, R136a1 and a2, we found previous magnitudes were underestimated by at least 0.4 mag. As such, luminosities and masses of these stars have to be significantly scaled down, which then also lowers the hitherto observed upper mass limit of stars.
The double distance and metallicity frontier marked by the SMC has been finally broken with the aid of powerful multi-object spectrographs installed at 8-10m class telescopes. VLT, GTC and Keck have enabled studies of massive stars in dwarf irregular galaxies of the Local Group with poorer metal-content than the SMC. The community is working to test the predictions of evolutionary models in the low-metallicity regime, set the new standard for the metal-poor high-redshift Universe, and test the extrapolation of the physics of massive stars to environments of decreasing metallicity. In this paper, we review current knowledge on this topic.
MASGOMAS (MAssive Stars in Galactic Obscured MAssive clusterS) is a project aiming at discovering OB stars in Galactic, dust enshrouded, star-forming massive clusters (Marín-Franch et al. 2009, A&A 502, 559). The project has gone through different phases of increasing automatization, that have allowed us to discover massive clusters like MASGOMAS-1 (Ramírez Alegría et al. 2012, A&A 541, A75) (with M≈20,000 M⊙).
Strong winds from massive stars are a topic of interest to a wide range of astrophysical fields. In High-Mass X-ray Binaries the presence of an accreting compact object on the one side allows to infer wind parameters from studies of the varying properties of the emitted X-rays; but on the other side the accretor’s gravity and ionizing radiation can strongly influence the wind flow. Based on a collaborative effort of astronomers both from the stellar wind and the X-ray community, this presentation attempts to review our current state of knowledge and indicate avenues for future progress.
Recently, new views of the current status of δ Scuti stars have been developed by Rodríguez & Breger (2001) who carried out an excellent review, listing 8 pre-main-sequence (PMS) δ Scuti candidates and examined the possibility of the existence of PMS δ Scuti variable stars. Here we discuss the nature of 4 stars from their list: 2 said to be members of NGC 2264 and 2 of NGC 6823.
We present the results from an optical monitoring campaign aimed at studying the
afterglow properties of the short GRB 100816A. We implemented a new way of processing the
Swift-BAT data, and based on it we reclassified this burst as short,
discarding the initial classification as long. Observations were carried out mainly with
the GTC Telescope within the four following days after the burst to investigate the
optical photometry of its afterglow, and a year later to localize the host. We completed
the optical imaging with the 1.23 m and 3.5 m CAHA Telescopes. We built and fitted the
nIR-optical SED for the characterization of the host. The best fit of the SED
(χ2/d.o.f. = 1.656) obtained for assumed values of a solar
metallicity, and an extinction of AV = 0.2mag is obtained for
a starburst galaxy with a dominant stellar population aging about 360 Myr.
Previously, an in vitro effect was observed on the complement system not only of the excretory-secretory products but also of somatic antigens from L3 Anisakis simplex larvae. In the present work the effect of anti-A. simplex specific antibodies on C3 and C4 levels in human sera was investigated. Up to 309 samples of sera were tested to determine levels of C3 and C4 and anti-A. simplex antibodies, including immunoglobulins IgG, IgM, IgA and IgE. Significant differences were observed between levels of C3 and C4 and all immunoglobulins except for IgE. In the case of immunoglobulins, the probability that an anti-A. simplex positive subject has a C3 deficiency was 3.8 times higher than a subject without specific antibodies. In conclusion, an association between elevated levels of anti-A. simplex antibodies and C3 and C4 deficiency was demonstrated.
This study was aimed to investigate in vitro and in vivo behavior of a Ti6Al7Nb biomaterial with a nanostructured HA-type coating and also the design and realization of a new special knee implant together with a selection of a suitable animal model for preclinical experimentation of the implants.
The metallic material used like substrate alloy for layer deposition was a Ti6Al7Nb alloy obtained by double electron beam melting furnace. In order to obtain a nano-crystalline HA-coating first sodium titanate layer was obtained on the surface and then the implant was immersed in Ringer solution with additional PAW1 biovitroceramic (particles under 20 μm). Different deposition times (5, 10 and 19 days) were employed. Microscopy analysis and corrosion tests of the implants relieves that the nanostructured HA layer after 19 days of immersion shows promising results as regarding the implant employ in preclinical experiments.
After a complex design based on knee bone radiography there has been manufactured two different types of devices for the metallic implants: a metallic plate and a pin. Two plates and two pins were implanted in each animal.
For in vivo experiments the chosen animal model was the mini-pig because of its strong chirurgical resistance and perfect anesthesia toleration. For the testing 10 animals were used for implantation and one for the control. When the plate is implanted the bone has to have a good blood supply after the cut in order to avoid bone to die. All experimented implants were maintained in the animal during six months and periodically inspected. No sign of infection or another problem were observed during this period.
Of the numerous requirements for advanced VLSI silicon microelectronics, power dissipation per unit area, speed, packing density and radiation hardness are especially important. Power dissipation and speed have forced an evolutionary path from PMOS to NMOS to NMOS E/D and to the currently used CMOS. As evidenced by the large number of publications, CMOS on an insulating substrate is receiving increased attention due to its potential as the next generation in MOS evolution. We review results of our previous and current research in silicon on sapphire (SOS) which has led to high quality ultrathin SOS (<100 nm thick) appropriate for high density CMOS circuitry. Basic materials developments, device performance, and CMOS design considerations in 100 nm thick improved SOS will be discussed.
GaInAs/GaAs/GaInP multiquantum well laser structures have been grown by chemical beam epitaxy (CBE) using conventional sources (hydrides as group V element sources). Large area lasers were photolitographically defined and mounted for continuous wave (CW) measurements. CW output power levels of 600 mW at 25°C are reported from 100 μm wide, 300 μm long laser diodes without any facet treatment. At these levels, the delivered current is 2A, with an associated voltage of less than 1.7 V. The characteristic temperature of the structure is 95 K.
The same structures were then grown using tertiarybutylarsine (TBAs) and tertiarybutylphosphine (TBP). The large area laser diodes were characterized under pulsed conditions. For a 300 μm long cavity, threshold current density of 390 A/cm2 and external quantum efficiency of 0.6 W/A (2 facets) were obtained, demonstrating the suitability of TBP and TBAs as substitutes of arsine and phosphine in chemical beam epitaxy for laser fabrication.
The thermal stability of ion irradiated 1.7 μm thick AZ-1350J photoresist films was investigated using the RBS and ERDA techniques to measure the composition of the irradiated and annealed films. The films have been irradiated with He, N and Ar ions at energies from 380 to 760 keV and fluences between 2 × 1015 and 1016 ions cm−2. A considerable increase in the thermal stability of the He irradiated film is observed from ≈200°C – when the non-irradiated film starts to decompose – to 400°C after the irradiation. The FTIR spectroscopy and the SEM observations were used to study the chemical structural changes and the surface morphology of the irradiated samples. The results are discussed in terms of the energy density deposited by the ions, the large loss of H during irradiation, and the resulting increase in cross-linking density.
In this study a group of resorcinol-formaldehyde carbon cryogels (CC) have been processed chemically, via catalysis and activation, to obtain varied nanostructures and pore size distributions. To understand the relation between structure and electrochemical properties the capacitor can be studied as a dielectric system composed of a porous electrode and the electrolyte (Tetraethylammonium tetrafluoroborate in propylene carbonate). Using Electrochemical impedance spectroscopy (EIS) the complex capacitance and power are used to study the behavior of the system below the relaxation frequency fo (φ = −45°). Therefore, the relaxation of the capacitor system at the low frequency range, f < fo, may be used as a measure of pore/electrolyte interaction. The approach here proposed also allows for a direct experimental characterization of the capacitance and power at low frequencies where small pores are likely to affect the diffusion dynamics of the electrolyte molecules. The results suggest a correlation between the occurrence of small micropores and that of high power losses that are related to the resistive element produced at the low frequency range. Moreover, the impact of the micropore structure upon the supercapacitor's performance is apparent in its capacitance and energy as well. In addition to the complex power and capacitance other measurements including BET Nitrogen sorption, cyclic voltammetry, galvanic cycling and X-Ray Raman Scattering were used to characterize the samples and support these results.
The endangered patellid limpet Cymbula nigra is present in the extreme western Mediterranean, yet the species has rarely been the subject of study in this region. The aim of the present research is to describe the ecology, distribution and population structure of the species in an area of the Mediterranean coast of North Africa (Ceuta). Results indicate that the species prevails in waters that have an important Atlantic influence. Furthermore, different shell morphologies are distinguished, and in consequence, a statistical analysis is carried out based on morphometric data. Based on maximum shell length, height/length coefficients and shell morphology, a total of three significantly different morphologies are described. Furthermore, considering physical parameters such as height over seawater level and average substratum inclination, juveniles resulted to be clearly segregated from the two other groups. Additionally, no differences were found regarding the topography of the substrate used by juvenile and adult individuals, although the colonized surfaces are significantly smoother than those where Patella ferruginea is present.
We analysed variations in swordfish capture and total by-catches, under different oceanographic and technical conditions, in the artisanal longline fishery operating in the Alboran Sea during the summer period. The oceanographic variable Sea Surface Velocity absolute component (SSV; m s−1) was the variable with the greatest explanatory power, as it was present in all models.
27 Creole and 27 Plymouth Rock×Rhode Island Red hens (cross) 47 months old were used to estimate the effect of three diets; commercial diet, corn+alfalfa and homemade diet on egg weight, white, yolk, egg shell, dry matter, protein, fat and ash content of the yolk; lipid fraction and fatty acid profile of the yolk was estimated too. Eggs were collected at 53 weeks of age, 30 eggs per treatment were randomly selected for laboratory analysis. No differences (P>0.05) were found on egg, white, yolk and egg shell weight between genetic groups; inside groups there was a significant effect of diet on yolk weight in both groups. There was no effect of diet and genetic group on yolk composition (P>0.05); however there was a trend of less content of dry matter and more ash with the homemade diet in both groups. There was a group effect (P<0.05) on cholesterol, cholesterol esters and lecithin content; inside groups there was a diet effect (P<0.05) on total lipid content and triglycerides. No differences (P>0.05) between groups were found for the fatty acid profile; inside groups stearic acid was higher (P<0.05) in the yolk of hens fed with no commercial diet and linoleic acid percentage was higher (P<0.05) with corn plus alfalfa diet. Results indicated that corn+alfalfa and homemade diet seem to alter the egg components, yolk lipids and fatty acid profile.
This work aimed at treating the new database on cesium-137 and strontium-90 transfer by wash-off collected by IRSN in the framework of the Franco-German Initiative for Chernobyl. It focused on the 71 runoff plot (from 1 to 400 m2) experiments conducted under artificial rainfalls in the Chernobyl district between 1986 and 1998. These data, mostly still unpublished, provide a quantification of wash-off at the rainfall scale, still rare for radionuclides. Normalized entrainment coefficients by liquid and solid wash-off were calculated for each experiment. In average, the liquid entrainment coefficient was 10-5 mm-1 for cesium, and 10-3.8 mm-1 for strontium. The solid entrainment coefficient was 10-41 m2g-1 for cesium and 10-4.3 m2g-1 for strontium. These trends and values were found consistent with reported values in the literature. For assessment purposes, the extrapolation of these coefficients to wider areas and to other sites would need their physical interpretation.