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Cosmological shock waves are ubiquitous to cosmic structure formation and evolution. As a consequence, they play a major role in the energy distribution and thermalization of the intergalactic medium (IGM). We analyze the Mach number distribution in the Dianoga simulations of galaxy clusters performed with the SPH code gadget -3. The simulations include the effects of radiative cooling, star formation, metal enrichment, supernova, and active galactic nuclei feedback. A grid-based shock-finding algorithm is applied in post-processing to the outputs of the simulations. This procedure allows us to explore in detail the distribution of shocked cells and their strengths as a function of cluster mass, redshift, and baryonic physics. We also pay special attention to the connection between shock waves and the cool-core/non-cool-core (CC/NCC) state and the global dynamical status of the simulated clusters. In terms of general shock statistics, we obtain a broad agreement with previous works, with weak (low-Mach number) shocks filling most of the volume and processing most of the total thermal energy flux. As a function of cluster mass, we find that massive clusters seem more efficient in thermalizing the IGM and tend to show larger external accretion shocks than less massive systems. We do not find any relevant difference between CC and NCC clusters. However, we find a mild dependence of the radial distribution of the shock Mach number on the cluster dynamical state, with disturbed systems showing stronger shocks than regular ones throughout the cluster volume. [ABSTRACT FROM AUTHOR]

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Using a sample of cosmic voids identified in the Sloan Digital Sky Survey Data Release 7, we study the star formation activity of void galaxies. The properties of galaxies living in voids are compared with those of galaxies living in the void shells and with a control sample, representing the general galaxy population. Void galaxies appear to form stars more efficiently than shell galaxies and the control sample. This result cannot be interpreted as a consequence of the bias towards low masses in underdense regions, as void galaxy subsamples with the same mass distribution as the control sample also show statistically different specific star formation rates. This highlights the fact that galaxy evolution in voids is slower with respect to the evolution of the general population. Nevertheless, when only the star-forming galaxies are considered, we find that the star formation rate is insensitive to the environment, as the main sequence is remarkably constant in the three samples under consideration. This fact implies that environmental effects manifest themselves as fast quenching mechanisms, while leaving the non-quenched galaxies almost unaffected, as their star formation activity is largely regulated by the mass of their halo. We also analyse galaxy properties as a function of void-centric distance and find that the enhancement in the star formation activity with respect to the control sample is observable up to a radial distance 1.5Rvoid. This result can be used as a suitable definition of void shells. Finally, we find that larger voids show an enhanced star formation activity in the shells with respect to their smaller counterparts, which could be related to the different dynamical evolution experienced by voids of different sizes. [ABSTRACT FROM AUTHOR]

The massive exploitation of cosmic voids for precision cosmology in the upcoming dark energy experiments, requires a robust understanding of their internal structure, particularly of their density profile. We show that the void density profile is insensitive to the void radius both in a catalogue of observed voids and in voids from a large cosmological simulation. However, the observed and simulated voids display remarkably different profile shapes, with the former having much steeper profiles than the latter. We ascribe such difference to the dependence of the observed profiles on the galaxy sample used to trace the matter distribution. Samples including low-mass galaxies lead to shallower profiles with respect to the samples where only massive galaxies are used, as faint galaxies live closer to the void centre. We argue that galaxies are biased tracers when used to probe the matter distribution within voids. [ABSTRACT FROM PUBLISHER]

Non-linear evolution of cosmological energy density fluctuations triggers deviations from Gaussianity in the temperature distribution of the cosmic microwave background. A method to estimate these deviations is proposed. N-body simulations – in a Λ cold dark matter cosmology – are used to simulate the strongly non-linear evolution of cosmological structures. It is proved that these simulations can be combined with the potential approximation to calculate the statistical moments of the cosmic microwave background anisotropies produced by non-linear gravity. Some of these moments are computed and the resulting values are different from those corresponding to Gaussianity. [ABSTRACT FROM AUTHOR]

In this contribution we present the results of an Eulerian adaptive mesh refinement (AMR) hydrodynamical and N-body simulation in a ΛCDM cosmology. The simulation used was performed with the cosmological code MASCLET (Quilis et al. 2004). Galaxies have been identified in the simulation outputs by means of an adaptive friends of friends algorithm applied to the star particles. To give light to our virtual galaxies we have assigned a spectrum to each stellar particle using the MIUSCAT stellar population models (Vazdekis et al. 2012; Ricciardelli et al. 2012). [ABSTRACT FROM PUBLISHER]

We perform a series of simulations of a Galactic mass dark matter halo at different resolutions: our largest uses over 3 billion particles and has a mass resolution of . We quantify the structural properties of the inner dark matter distribution and study how they depend on numerical resolution. We can measure the density profile to a distance of 120 pc (0.05 per cent of ), where the logarithmic slope is −0.8 and −1.4 at (0.5 per cent of ). We propose a new two-parameter fitting function that has a linearly varying logarithmic density gradient over the resolved radii which fits the GHALO and VL2 density profiles extremely well. Convergence in the halo shape is achieved at roughly three times the convergence radius for the density profile at which point the halo becomes more spherical due to numerical resolution. The six-dimensional phase-space profile is dominated by the presence of the substructures and does not follow a power law, except in the central few kpc which is devoid of substructure even at this resolution. The quantity, , which is often used as a proxy for the six-dimensional phase-space density should be used with caution. [ABSTRACT FROM AUTHOR]

Objective: To describe and assess the consumption of the information consulted and cited in the articles published in the journal Nutrición Hospitalaria for the period 2001-2005 by means of bibliometric analysis. Method: Cross-sectional descriptive analysis of the results obtained from the analysis of the lists of bibliographic references of the articles published at Nutrición Hospitalaria. We studied the most cited journals, the signatures index, the type of document referred, the publication language, the distribution of geographical origin, and obsolescence and readiness index. We took into account all types of documents with the exception of Communications to Congresses. Results: 345 articles were published at Nutr Hosp, containing 8,113 bibliographic references, with a median of 18, a maximum of 136 and minimum of 0 BR per article. The mean (rate of publications per published article during the specified period) is 23.52 (95% IC 20.93-26.10) and the mean at 5% is 20.66 per article. The 25th and 75th percentiles are 6 and 32, respectively, the interquartile interval being 26 BR per document. The semi-period of Burton and Kebler is 7 years and the Price Index is 38.18%. Conclusion: The bibliographic references, the consumption of information, of the articles published at Nutrición Hospitalaria present parameters similar to other journals on health science. However, good data onobsolescence are observed, which reveal the good validity of most of the references studied. [ABSTRACT FROM AUTHOR]

Objective: To describe and assess the consumption of the information consulted and cited in the articles published in the journal "Nutrición Hospitalaria" for the period 2001-2005 by means of bibliometric analysis. Method: Cross-sectional descriptive analysis of the results obtained from the analysis of the lists of bibliographic references of the articles published in "Nutrición Hospitalaria." We studied the most cited journals, the signatures index, the type of document referred, the publication language, the distribution of geographical origin, and obsolescence and readiness index. We took into account all types of documents with the exception of Communications to Congresses. Results: 345 articles were published in "Nutr Hosp," containing 8,113 bibliographic references, with a median of 18, a maximum of 136 and minimum of 0 BR per article. The mean (rate of publications per published article during the specified period) is 23.52 (95% IC 20.93- 26.10) and the mean at 5% is 20.66 per article. The 25th and 75th percentiles are 6 and 32, respectively, the interquartile interval being 26 BR per document. The semi-period of Burton and Kebler is 7 years and the Price Index is 38.18%. Conclusion: The bibliographic references, the consumption of information, of the articles published in "Nutrición Hospitalaria" present parameters similar to other journals on health science. However, good data on obsolescence are observed, which reveal the good validity of most of the references studied. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To assess the scientific activity and information production of the journal Nutrición Hospitalaria, for the period 2001-2005 by means of a Bibliometric study. METHOD: Cross-sectional descriptive study of the results obtained from the analysis of the articles published in the journal Nutrición Hospitalaria. The data were obtained by consulting the electronic version through the Web. In those cases in which there was a link breakdown, and thus, the inability to have access to the electronic document the printed version was consulted. All the documental possibilities were taken into account with the exception of communications to congresses. RESULTS: A total of 345 articles were published, 187 (54.20%) being original articles. The geographical distribution of the first author was Spanish in 287 articles (83.19%) and Latin American in 27 (7.83%). Most of the articles are from health care centers (172 articles (49.86%)), and the cooperation index being 4.15. Madrid is the most productive province, for both the absolute and adjusted frequencies. The median number of references per article is 18, the mean being 23.52 (95% CI 20.93 - 26.10). The predominant language was Spanish, with 308 articles (89.28%). CONCLUSION: Nutrición Hospitalaria may be considered as a reference journal regarding information and scientific communication on Nutrition for both the Spanish and Latin American communities. The bibliometric parameters studied compare with those verified for the remaining top of the list Spanish scientific journals on health sciences. [ABSTRACT FROM AUTHOR]

Objective: To assess the scientific activity and information production of the journal Nutrición Hospitalaria, for the period 2001-2005 by means of a Bibliometric study. Method: Cross-sectional descriptive study of the results obtained from the analysis of the articles published in the journal Nutrición Hospitalaria. The data were obtained by consulting the electronic version through the Web. In those cases in which there was a link breakdown, and thus, the inability to have access to the electronic document the printed version was consulted. All the documental possibilities were taken into account with the exception of communications to congresses. Results: A total of 345 articles were published, 187 (54.20%) being original articles. The geographical distribution of the first author was Spanish in 287 articles (83.19%) and Latin American in 27 (7.83%). Most of the articles are from health care centers (172 articles (49,86%)), and the cooperation index being 4.15. Madrid is the most productive province, for both the absolute and adjusted frequencies. The median number of references per article is 18, the mean being 23.52 (95% CI 20.93 - 26.10). The predominant language was Spanish, with 308 articles (89.28%). Conclusion: Nutrición Hospitalaria may be considered as a reference journal regarding information and scientific communication on Nutrition for both the Spanish and Latin American communities. The bibliometric parameters studied compare with those verified for the remaining top of the list Spanish scientific journals on health sciences. [ABSTRACT FROM AUTHOR]

The Statement by the Spanish Society of Family and Community Medicine (SemFYC) on access to scientific information, highlights the need for providing digital libraries with certain resources in Autonomous Regions. The primary goal is to study the evidence-based medicine (EBM) coverage that SemFYC recommends regional virtual libraries. The regional health virtual libraries were identified and the access provided to health professionals, Internet presence, remote access and resources were studied. The results suggest there is ample coverage in 8 Autonomous Regions. At the top of the list was, Health Sciences Virtual Library of Navarre, the Balearic Islands Health Sciences Virtual Library, and Virtual Library of the Andalusian Public Health System. The present study needs to be extended to the other biomedical sciences, in order to obtain more accurate results., (Copyright © 2012 Elsevier España, S.L. All rights reserved.)

This is the fourth in a series of articles exploring international trends in health science librarianship in four Southern European countries in the first decade of the 21st century. The invited authors are from Greece, Italy, Spain and Portugal. Future issues will track trends in Latin America and Central Europe., (© 2012 The authors. Health Information and Libraries Journal © 2012 Health Libraries Group.)

Glioblastomas express a notable heterogeneity in both the histological and cell patterns with glial astrocytic differentiation. Primary glioblastoma, which is the most frequent presentation (90-95%), occurs mainly in older patients and arises de novo, without any clinical or histological evidence of a less malignant precursor lesion. EGFR amplification has been identified as a genetic hallmark of primary glioblastomas and occurs in 40-60% of cases. However, there exist primary glioblastomas without EGFR amplification/overexpression. The purpose of this study was to stabilize the association between cases with and without EGFR gene amplification with clinical and genetic parameters in 45 cases of primary glioblastomas. EGFR amplification was observed in 24 cases (53%), while in the remaining 21 cases (47%) this alteration was not displayed. And whereas EGFR was overexpressed in 79% of cases with EGFR amplification, only 33% of the cases without EGFR amplification showed overexpression. The amplification of EGFR was associated with amplifications in MDM2 and CDK4 and a higher percentage of cases with promoter methylation of INK4a. Only one case of glioblastoma with EGFR amplification presented TP53 mutation simultaneously. Seven remaining cases with TP53 mutations were glioblastomas without EGFR amplification. The INK4a, INK4b and ARF deletions were similar in the two groups. Primary glioblastomas with and without EGFR amplification did not show any significant differences in average survival. The genetic studies suggest the existence of molecular subtypes within primary glioblastoma that may, when fully defined, contribute toward the development of drugs that specifically target tumors with divergent genetic profiles.

Gene amplification is a process that is characterized by an increase in the copy number of a restricted region in a chromosome arm, and is frequently associated with an overexpression of the corresponding amplified gene. Amplified DNA can be organized either as extrachromosomal elements, repeated units at a single locus or scattered throughout the genome. The amplification of the gene for epidermal growth factor receptor (EGFR) is a common finding in glioblastomas and the amplified gene copies appears as double minutes. The aim of this study was to investigate the different patterns of EGFR amplification in 40 cases of glioblastoma using FISH analysis in metaphases and paraffin sections, and to investigate the relationship of gene copy number with gene expression profile. The analysis of copy number alterations of EGFR was validated by quantitative PCR and SNP microarrays. We observed that in 42% of the cases, the type of amplification of EGFR was as double minute chromosomes. In addition, we detected another type of amplification, with extra copies of EGFR inserted in different loci of chromosome 7, present in 28% of cases. In this form of amplification, the number of copies is small, and the percentage of cells with EGFR amplification is rarely more than 15%. This model of amplification could correspond to a variant of the insertion mechanism, or a consequence of a process of duplication. Our results suggest that this mechanism could represent an early stage of amplification in glioblastomas. Overall, we found a close correlation between EGFR gene copy-number alterations and the level of EGFR protein expression. However, all cases with a high level of mRNA exhibited strong expression for the EGFR protein, and most cases with a low level of mRNA showed no overexpression of EGFR protein.

Object: Nowadays the role of microsurgical management of intrinsic brain tumors is to maximize the volumetric resection of the tumoral tissue, minimizing the postoperative morbidity. The purpose of this paper was to study the benefits of an original protocol developed for the microsurgical treatment of tumors located in eloquent motor areas where the navigation and electrical stimulation of motor subcortical pathways have been implemented., Methods: A total of 17 patients who underwent resection of cortical or subcortical tumors in motor areas have been included in the series. The preoperative planning for multimodal navigation was done by integrating anatomical studies, motor functional MR (fMR) imaging, and subcortical pathway volumes generated by diffusion tensor (DT) imaging. Intraoperative neuromonitoring included motor mapping by direct cortical stimulation (CS) and subcortical stimulation (sCS), and localization of the central sulcus by using cortical multipolar electrodes and the N20 wave inversion technique. The location of all cortically and subcortically stimulated points with positive motor response was stored in the navigator and correlated with the cortical and subcortical motor functional structures defined preoperatively., Results: The mean tumoral volumetric resection was 89.1 +/- 14.2% of the preoperative volume, with a total resection (> or = 100%) in 8 patients. Preoperatively a total of 58.8% of the patients had some kind of motor neurological deficit, increasing 24 hours after surgery to 70.6% and decreasing to 47.1% at 1 month later. There was a great correlation between anatomical and functional data, both cortically and subcortically. A total of 52 cortical points submitted to CS had positive motor response, with a positive correlation of 83.7%. Also, a total of 55 subcortical points had positive motor response; in these cases the mean distance from the stimulated point to the subcortical tract was 7.3 +/- 3.1 mm., Conclusions: The integration of anatomical and functional studies allows a safe functional resection of the brain tumors located in eloquent areas. Multimodal navigation allows integration and correlation among preoperative and intraoperative anatomical and functional data. Cortical motor functional areas are anatomically and functionally located preoperatively thanks to MR and fMR imaging and subcortical motor pathways with DT imaging and tractography. Intraoperative confirmation is done with CS and N20 inversion wave for cortical structures and with sCS for subcortical pathways. With this protocol the authors achieved a good volumetric resection in cortical and subcortical tumors located in eloquent motor areas, with an increase in the incidence of neurological deficits in the immediate postoperative period that significantly decreased 1 month later. Ongoing studies must define the safe limits for functional resection, taking into account the intraoperative brain shift. Finally, it must be demonstrated whether this protocol has any long-term benefit for patients by prolonging the disease-free interval, the time to recurrence, or the survival time.

Background: The documentation produced by public and private institutions in relation to the chemical risk constitutes an essential tool for prevention. The objective of this research is to locate and to revise the documents related to the management of the prevention of chemical risk focus to PYMES in Spain from 1995 to 2004., Methods: The methodology carried out for the selection of the bibliographical materials has been the consultation of automated databases and Web pages., Results: 812 documents have been identified. Most corresponds to grey literature. The thematic more frequent has been the security and the most frequent objective of the papers has been the prevention. Most of the documents go to the technical sector., Conclusions: The results suggest that although that there is a great diversity of documents in Spain dedicated to the prevention of chemical risk it seems convenient: 1) to increase their diffusion, 2) to pay attention to the communication of the risks, 3) to investigate and to translate the research in good practice.

We present three-dimensional, high-resolution hydrodynamical simulations of the interaction between the hot ionized intracluster medium and the cold interstellar medium of spiral galaxies. Ram pressure and turbulent/viscous stripping remove 100% of the atomic hydrogen content of luminous galaxies like the Milky Way within 100 million years. These mechanisms naturally account for the morphology of S0 galaxies and the rapid truncation of star formation implied by spectroscopic observations, as well as a host of observational data on the neutral hydrogen (HI) morphology of galaxies in clusters.

We compare the structure and substructure of dark matter halos in model universes dominated by collisional, strongly self-interacting dark matter (SIDM) and collisionless, weakly interacting dark matter (CDM). While SIDM virialized halos are more nearly spherical than CDM halos, they can be rotationally flattened by as much as 20% in their inner regions. Substructure halos suffer ram-pressure truncation and drag, which are more rapid and severe than their gravitational counterparts tidal stripping and dynamical friction. Lensing constraints on the size of galactic halos in clusters are a factor of 2 smaller than predicted by gravitational stripping, and the recent detection of tidal streams of stars escaping from the satellite galaxy Carina suggests that its tidal radius is close to its optical radius of a few hundred parsecs-an order of magnitude smaller than predicted by CDM models but consistent with SIDM models. The orbits of SIDM satellites suffer significant velocity bias, sigmaSIDM&solm0;sigmaCDM=0.85, and are more circular than CDM satellites, betaSIDM approximately 0.5, in agreement with the inferred orbits of the Galaxy's satellites. In the limit of a short mean free path, SIDM halos have singular isothermal density profiles; thus, in its simplest incarnation SIDM, is inconsistent with galactic rotation curves.