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Boltzmann–Gibbs statistical mechanics applies satisfactorily to a plethora of systems. It fails however for complex systems generically involving nonlocal space–time entanglement. Its generalization based on nonadditive q-entropies adequately handles a wide class of such systems. We show here that scale-invariant networks belong to this class. We numerically study a d-dimensional geographically located network with weighted links and exhibit its 'energy' distribution per site at its quasi-stationary state. Our results strongly suggest a correspondence between the random geometric problem and a class of thermal problems within the generalised thermostatistics. The Boltzmann–Gibbs exponential factor is generically substituted by its q-generalisation, and is recovered in the q = 1 limit when the nonlocal effects fade away. The present connection should cross-fertilise experiments in both research areas. [ABSTRACT FROM AUTHOR]

We have investigated SiC layers produced by ion beam synthesis on Si(111) substrates using different procedures. Bare Si(111) and SiO2/Si(111) structures were implanted with carbon at 40 keV up to a fluence of 4×1017 cm-2 at a temperature of 600 °C. Postimplantation annealing was carried out at 1250 °C for 2 h in pure O2 or Ar (with 1% of O2). A SiC layer was synthesized for all the procedures involving annealing under Ar. However, for the samples annealed under pure O2 flux, only that employing implantation into the bare Si(111) resulted in SiC synthesis. Rutherford backscattering spectrometry shows that, after annealing, the stoichiometric composition is obtained. Transmission electron microscopy measurements demonstrate the synthesis of cubic-SiC layers that are completely epitaxial to the Si(111) substrate. However, there is a high density of nanometric twins, stacking faults, and also narrow amorphous inclusions of laminar shape between the crystalline regions. The procedure based on high temperature implantation through a SiO2 cap, etching the cap off, 1250 °C postimplantation annealing under Ar ambient (with 1% of O2), and final etching has shown advantages from the point of view of surface flatness and increased layer thickness, keeping the same layer epitaxy and accurate composition. [ABSTRACT FROM AUTHOR]

We present a method to solve constrained convex stochastic optimization problems when the objective is a finite sum of convex functions. Our method is based on Incremental Stochastic Subgradient Algorithms and String-Averaging techniques, with an assumption that the subgradient directions are affected by random errors in each iteration. Our analysis allows the method to perform approximate projections onto the feasible set in each iteration. We provide convergence results for the case where a diminishing step-size rule is used. We test our method in a large set of random instances of a stochastic convex programming problem and we compare its performance with the robust mirror descent stochastic approximation algorithm proposed in Nemirovski et al. (Robust stochastic approximation approach to stochastic programming, SIAM J Optim 19 (2009), pp. 15741609). [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate the organizational support for learning and the impact of the Course on Improvement in Public Management in the perception of the Technical-Administrative managers in Education of a public institution of education, science and technology of the Northeast of Brazil. It is a qualitative research, with a mode of investigation in the case study and a descriptive objective. For the data collection it was used a structured interview through the ISAM (Integrated and Summative Assessment Model), proposed by Jairo Borges-Andrade, Jardim Abbad and Luciana Mourão. The data collected were processed in electronic spreadsheets and the results show that: in terms of organizational support, there were favorable organizational conditions and there was commitment of the organization to the learning of the new skills of the workers, as well as the absorption by the individuals / work groups about how much the organization values its contributions of new knowledge. As for the impact of the training, it has been verified that there were improvements in the individual performance of the trained servants through a new way of performing old tasks from the new skills acquired. [ABSTRACT FROM AUTHOR]

Hepatitis E virus ( HEV) is a zoonotic agent today considered a major Public Health issue in industrialized countries. HEV strains belonging to zoonotic genotype 3 are widely present in swine, being today considered important reservoirs for human disease. Unlike in swine, only scarce data are available on the circulation of HEV in wild boar. This study describes the detection and molecular characterization of HEV in livers from sylvatic wild boar hunted in Portugal and destined for consumption. Additionally, the detection of HEV in stools of a confined wild boar population also destined for consumption is also described. A total of 80 liver samples collected during the hunting season of 2011/2012 and 40 stools collected in February 2012 from a wild boar breeding farm in Portugal were tested by a nested broad-spectrum RT- PCR assay targeting open reading frame ( ORF) 1. Twenty livers (25.0%) and 4 stools (10%) were positive for HEV. Phylogenetic analysis showed that all strains clustered with sequences classified as HEV genotype 3 subgenotype e. To our knowledge, this is the first report documenting the occurrence and molecular analysis of HEV in sylvatic and captive wild boar destined for human consumption in Portugal. This report demonstrates for the first time the circulation of HEV in wildlife reservoirs of Portugal adding knowledge to the epidemiology of HEV in wild boar populations. [ABSTRACT FROM AUTHOR]

In this work nickelate nanoparticles were synthesized using a simple and fast new route, which makes use of gelatin as an organic precursor in order to evaluate the performance of the synthesis method to obtain materials and the influence of the strontium replacement on the structural parameters of the powders. Samples of Nd2-xSrxNiO4 (x = 0 and 0.4) were calcined at 700 and 900 °C at a heating of 10 °C/min for 4 hours. X-ray powder diffraction patterns were obtained for all the samples, and the Rietveld Method was applied in order to determine the crystallite size using Scherrer's equation, the lattice parameters, and phase concentration. The results obtained using these techniques confirmed that the main crystal structure consists of the distorted K2NiF4-type tetragonal I4/mmm. In addition, scanning electron microscopy images revealed the formation of nanosized particles. [ABSTRACT FROM AUTHOR]

The close relationship between the behavior of the edge plasma characteristics and the global confinement in discharges in tokamaks has been extensively explored in recent years. A 15 keV lithium beam with 80% neutralization efficiency, using a high ion current density emitter and a modified Pierce gun design for extraction of ions, was developed for edge studies on the spherical tokamak ETE—(major radius R=0.30 m, aspect ration A=1.5, designed plasma current of 200 kA with a torodial magnetic field up to 0.4 T). Already in the calibration phase this diagnostics confirmed to be an efficient experimental tool, allowing accurate measurements of the fast varying pressure of the discharges in ETE. The measurement of the temporal evolution of the density of the plasma edge with fast neutral lithium beam is in accordance with data from Langmuir probe for the region near the limiter and the one made by the Thomson scattering for the inner region. [ABSTRACT FROM AUTHOR]

Malignant glioma invasion is a primary cause of brain cancer treatment failure, yet the molecular mechanisms underlying its regulation remain elusive. We developed a novel functional-screening strategy and identified downregulated in renal cell carcinoma (DRR) as a regulator of invasion. We show that DRR drives invasion in vitro and in vivo. We found that while DRR is not expressed in normal glial cells, it is highly expressed in the invasive component of gliomas. Exploring underlying mechanisms, we show that DRR associates with and organizes the actin and microtubular cytoskeletons and that these associations are essential for focal adhesion (FA) disassembly and cell invasion. These findings identify DRR as a new cytoskeletal crosslinker that regulates FA dynamics and cell movement. [ABSTRACT FROM AUTHOR]

Among the Opiliones, species of the suborders Cyphophthalmi, Eupnoi, Dyspnoi and Laniatores have shown very diverse diploid chromosome numbers. However, only certain Eupnoi species exhibit XY/XX and ZZ/ZW sex chromosome systems. Considering the scarcity of karyotypical information and the absence of structurally identifiable sex chromosomes in the suborder Laniatores, we decided to analyse the chromosomes and bivalents of Discocyrtus pectinifemur (Gonyleptidae) to identify possible sex differences. Testicular cells examined under light microscopy showed a high diploid number, 2 n = 88, meta/submetacentric chromosome morphology and a nucleolar organizer region on pair 35. Prophase I microspreading observed in transmission electron microscopy exhibited 44 synaptonemal complexes with similar electron density and thickness. The total and regular synapsis between the chromosomes of the bivalents was also noted in pachytene nuclei. Male mitotic and meiotic chromosomes revealed no distinct characteristic that could be related to the occurrence of heteromorphic sex chromosomes. Evolutionary trends of chromosome differentiation in the four suborders of Opiliones are discussed here. [ABSTRACT FROM AUTHOR]

In this work we use single molecule force spectroscopy performed with optical tweezers in order to characterize the complexes formed between the anticancer drug Pixantrone (PIX) and the DNA molecule, at two very different ionic strengths. Firstly, the changes of the mechanical properties of the DNA-PIX complexes were studied as a function of the drug concentration in the sample. Then, a quenched-disorder statistical model of ligand binding was used in order to determine the physicochemical (binding) parameters of the DNA-PIX interaction. In particular, we have found that the PIX molecular mechanism of action involves intercalation into the double helix, followed by a significant compaction of the DNA molecule due to partial neutralization of the phosphate backbone. Finally, this scenario of interaction was quantitatively compared to that found for the related drug Mitoxantrone (MTX), which binds to DNA with a considerably higher equilibrium binding constant and promotes a much stronger DNA compaction. The comparison performed between the two drugs can bring clues to the development of new (and more efficient) related compounds. [ABSTRACT FROM AUTHOR]

To measure the electron temperature and plasma density profiles on the Experimento Tokamak Esférico tokamak a multiplexed Thomson scattering diagnostic was implemented. The diagnostic is based on a 10 J ruby laser and a single five spectral channel filter polychromator. A collection lens with f/6.3 relay the scattered light from 23 spatial points to optical fibers. The fibers have a monotonous increasing length and are inserted into the polychromator. Between the collection lens and each fiber optic we have a microlens to match the numerical aperture and to enlarge the plasma observation volume. This work describes the project, the simulations, and the preliminary results obtained with the first four optical fibers. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the chemical composition of meat from three portions of the carcass of kids raised in range conditions and slaughtered at 8-9 or 11-12 months old. The trial was conducted in the region of Alto Camaquã and had 15 animals per group. Chemical composition of the carcass (moisture, protein, ashes, fats, and cholesterol) was determined from the shoulder, loin, and legs. Kids slaughtered younger had higher moisture and ash content in all three portions (p<0.05) when compared to older animals. Fat levels only were higher in kids slaughtered at an older age (p<0.05). Cholesterol content only on the leg, was lesser than the two other portions in younger animals (p<0.05). There were no differences observed between the three portions on the older animals. Older kids at slaughter had higher content of protein and fat but cholesterol remained unchanged. The three portions of the carcass had distinct chemical composition. Our results suggest that in range conditions the slaughter of animals should occur at 11-12 months old, resulting in meat with higher nutritional content in all portions of the carcass. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carriage of Streptococcus pneumoniae is a key factor in the development of invasive disease and the spread of resistant strains within the community. A single nasopharyngeal swab was obtained from 648 unvaccinated children aged <5 years, either healthy or with acute respiratory tract infection or meningitis, during the winters of 2000 and 2001. The overall pneumococcal carriage rate was 35.8% (95% CI 32.1–39.6). The pneumococcal serotypes found most frequently in the nasopharynx were 14, 6B, 6A, 19F, 10A, 23F and 18C, which included five of the seven serotypes in the currently licensed seven-valent conjugate vaccine (PCV7); serotypes 4 and 9V were less common. Serotypes 1 and 5 were isolated rarely from the nasopharynx. A comparison of 222 nasopharyngeal isolates with 125 invasive isolates, matched for age and time to the carrier isolates, showed a similar prevalence of penicillin non-susceptible pneumococci (PNSp) (19.8% and 19.2%, respectively). PNSp serotypes were similar (6B, 14, 19F, 19 A, 23B and 23F) for carriage and invasive disease isolates. The coverage of PCV7 for carriage isolates (52.2%) and invasive isolates (62.4%) did not differ significantly (p 0.06); similarly, there was no significant difference in PCV7 coverage for carriage isolates (34.5%) and invasive isolates (28.2%) of PNSp. These data suggest that PCV7 has the potential to reduce pneumococcal carriage and the number of carriers of PNSp belonging to vaccine serotypes. [ABSTRACT FROM AUTHOR]

New designs for Magnetic Resonance Imaging contrast agents are presented. Essentially, they all are host–guest inclusion complexes between γ-cyclodextrins and polyazamacrocycles of gadolinium (III) ion. Substitutions have been made to the host to optimise the host–guest association. Molecular mechanics calculations have been performed, using the UFF force field for metals, to decide on the suitability of the substitutions, and to evaluate the host–guest energies of association. Interesting general conclusions have been obtained, concerning the improvement of Magnetic Resonance Imaging contrast agents; namely, a set of rational methodologies have been deduced to improve the association between the gadolinium (III) chelates and the cyclodextrins, and their efficiency is demonstrated with a large set of substituted complexes, opening new doors to increase the diagnostic capabilities of Magnetic Resonance Imaging. [ABSTRACT FROM AUTHOR]

A 10 J ruby laser Thomson scattering system was implemented on the ETE spherical tokamak to measure the density n[sub e] and temperature T[sub e] profiles. The laser probes the plasma at the horizontal midplane of the torus and the collection optics allows the observation of up to 22 points inside the plasma in the same plane. Radial profiles of plasma density and electron temperature were obtained for different times during the discharge by shot-to-shot procedure. Temperatures of up to 160 eV and densities of 2.2 × 10[sup 19] m[sup -3] were measured. Since the level of stray light was too high, the calibration of the Thomson scattering system for density measurements was made using the nitrogen Raman technique instead of the usually applied Rayleigh method. [ABSTRACT FROM AUTHOR]