5,589 research outputs found

    Histologic and Histomorphometric Analysis of Posterior Region of the Human Temporomandibular Disc

    Get PDF
    Objective The aim of this study was to analyze histologic and histomorphometric features of the articular disc in groups with and without disc displacement. Study design A sample of 39 temporomandibular joints TMJs (31 case specimens, 8 control specimens) from 28 patients (mean age 31.2 years) were recruited for this study. The patients were considered to be affected and treated surgically with disc repositioning when presenting painful clinical signs of disc displacement after unsuccessful nonsurgical treatment for at least 6 months. Of the control patients, 4 presented condyle fracture which required opening to be reduced for treatment, and 4 displayed active condyle hyperplasia. The posterior region of the disc was removed and sent for histologic and histomorphometric analysis. Histologic (hematoxylin-eosin) and histomorphometric (picro-Sirius red) analyses were performed. Statistically significant differences between the analyzed groups were accessed through the chi-squared test (P ≤ .05). The Mann-Whitney U test was used to observe the differences between mean values when variables did not present normal distribution [Kolmogorov-Smirnov(a) test]. Results There were no significant differences between the groups in relation to the parameters studied by histologic and histomorphometric analysis (using or not using polarization). Conclusions To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction

    IMF - metallicity: a tight local relation revealed by the CALIFA survey

    Get PDF
    Variations in the stellar initial mass function (IMF) have been invoked to explain the spectroscopic and dynamical properties of early-type galaxies. However, no observations have yet been able to disentangle the physical driver. We analyse here a sample of 24 early-type galaxies drawn from the CALIFA survey, deriving in a homogeneous way their stellar population and kinematic properties. We find that the local IMF is tightly related to the local metallicity, becoming more bottom-heavy towards metal-rich populations. Our result, combined with the galaxy mass-metallicity relation, naturally explains previous claims of a galaxy mass-IMF relation, derived from non-IFU spectra. If we assume that - within the star formation environment of early-type galaxies - metallicity is the main driver of IMF variations, a significant revision of the interpretation of galaxy evolution observables is necessary.Comment: Accepted for publication in ApJL. 6 pages, 4 figure

    Spatial and temporal diversity in genomic instability processes defines lung cancer evolution

    Get PDF
    PMCID: PMC4636050.-- et al.Spatial and temporal dissection of the genomic changes occurring during the evolution of human non-small cell lung cancer (NSCLC) may help elucidate the basis for its dismal prognosis.We sequenced 25 spatially distinct regions from seven operable NSCLCs and found evidence of branched evolution, with driver mutations arising before and after subclonal diversification. There was pronounced intratumor heterogeneity in copy number alterations, translocations, and mutations associated with APOBEC cytidine deaminase activity. Despite maintained carcinogen exposure, tumors from smokers showed a relative decrease in smoking-related mutations over time, accompanied by an increase in APOBEC-associated mutations. In tumors from former smokers, genome-doubling occurred within a smoking-signature context before subclonal diversification, which suggested that a long period of tumor latency had preceded clinical detection. The regionally separated driver mutations, coupled with the relentless and heterogeneous nature of the genome instability processes, are likely to confound treatment success in NSCLC.E.B. is a Rosetrees Trust fellow; M.J.H. has a Cancer Research UK fellowship; N.Mu. received funding from the Rosetrees Trust; M.G. is funded by the UK Medical Research Council; I.V. is funded by Spanish Ministerio de Economía y Competitividad subprograma Ramón y Cajal; R.C.R. and D.M.R. are partly funded by the Cambridge Biomedical Research Centre and Cancer Research UK Cancer Centre; P.V.L. is a postdoctoral researcher of the Research Foundation—Flanders (FWO); S.M.J. is a Wellcome Senior Fellow in Clinical Science; and C.S. is a senior Cancer Research UK clinical research fellow and is funded by Cancer Research UK, the Rosetrees Trust, European Union Framework Programme 7 (projects PREDICT and RESPONSIFY, ID:259303), the Prostate Cancer Foundation, the European Research Council and the Breast Cancer Research Foundation. This research is supported by the National Institute for Health Research University College London Hospitals Biomedical Research Centre.Peer Reviewe

    The structural and dynamical properties of compact elliptical galaxies

    Full text link
    Dedicated photometric and spectroscopic surveys have provided unambiguous evidence for a strong stellar mass-size evolution of galaxies within the last 10 Gyr. The likely progenitors of today's most massive galaxies are remarkably small, disky, passive and have already assembled much of their stellar mass at redshift z=2. An in-depth analysis of these objects, however, is currently not feasible due to the lack of high-quality, spatially-resolved photometric and spectroscopic data. In this paper, we present a sample of nearby compact elliptical galaxies (CEGs), which bear resemblance to the massive and quiescent galaxy population at earlier times. Hubble Space Telescope (HST) and wide-field integral field unit (IFU) data have been obtained, and are used to constrain orbit-based dynamical models and stellar population synthesis (SPS) fits, to unravel their structural and dynamical properties. We first show that our galaxies are outliers in the present-day stellar mass-size relation. They are, however, consistent with the mass-size relation of compact, massive and quiescent galaxies at redshift z=2. The compact sizes of our nearby galaxies imply high central stellar mass surface densities, which are also in agreement with the massive galaxy population at higher redshift, hinting at strong dissipational processes during their formation. Corroborating evidence for a largely passive evolution within the last 10 Gyr is provided by their orbital distribution as well as their stellar populations, which are difficult to reconcile with a very active (major) merging history. This all supports that we can use nearby CEGs as local analogues of the high-redshift, massive and quiescent galaxy population, thus providing additional constraints for models of galaxy formation and evolution.Comment: 33 pages, 27 figures and 20 tables (with most of the tables provided as online-only supporting information). Accepted for publication in MNRA

    El concepto de ‘estándares internacionales de derechos humanos’ según la doctrina jurídica”

    Get PDF
    Este artículo contiene el estado del arte sobre la naturaleza y valor jurídico de los denominados “estándares internacionales de derechos humanos”. Se señala lo que han dicho los pocos teóricos que se han preguntado acerca de qué son los estándares y si ellos son fuente de derecho internacional. Son diez autores, dos que escriben en inglés y el resto en castellano. Se incluye una valoración personal del autor del texto sobre el alcance y los aportes de cada uno al necesario estudio sobre el fenómeno del uso tan extendido de esa expresión.  &nbsp

    Analysis of contents about sexuality and human reproduction in school textbooks in Spain

    Get PDF
    Objectives: The spread of sexually transmitted infections (STI) in adolescents and teenage pregnancy rates are increasing. A decrease in the average age of youth’s first sexual experience is also being noted. Sexual education programs in schools have an important role to play in addressing these issues. The objective of this study is to analyze the content of textbooks in the area of sexuality and human reproduction in order to evaluate the extent to which these textbooks promote healthy reproductive life styles, as well as risk behavior avoidance among the adolescent students. Study design: Descriptive study of school textbooks content. Methods: The study sample consisted of 12 textbooks (about 80% of all the textbooks) used in Spanish secondary school and edited in 2002. A content analysis evaluated the extent to which these books demonstrated reliable scientific information about: a) condom effectiveness; b) consequences, prevention, and treatment of STI; c) family planning methods; d) Assisted reproductive technologies and e) the promotion of healthy reproductive lifestyles. Results: All textbooks presented inaccurate information in the areas studied. Two hundred and eighty one quotes were identified that facilitated an incomplete perception of sexuality or enabled risky behavior. An average of 12.6 incorrect messages was identified in each textbook. Conclusions: The textbooks examined are neither appropriate nor comprehensive enough for adolescent education on issues of sexuality. Results suggest a need for alternative textbooks based on better scientific evidence. It is essential that textbooks empower adolescents to make healthy decisions through the promotion of useful life skills that provide a more integrated concept of sexuality. In any case, there is a need for approaches to sexual education to integrate values commonly held by parents of the youth that use such texts
    corecore