1,560 research outputs found

    On the Excitation and Formation of Circumstellar Fullerenes

    Get PDF
    We compare and analyze the Spitzer mid-infrared spectrum of three fullerene-rich planetary nebulae in the Milky Way and the Magellanic Clouds; Tc1, SMP SMC16, and SMP LMC56. The three planetary nebulae share many spectroscopic similarities. The strongest circumstellar emission bands correspond to the infrared active vibrational modes of the fullerene species C60 and little or no emission is present from Polycyclic Aromatic Hydrocarbons (PAHs). The strength of the fullerene bands in the three planetary nebulae is very similar, while the ratio of the [NeIII]15.5um/[NeII]12.8um fine structure lines, an indicator of the strength of the radiation field, is markedly different. This raises questions about their excitation mechanism and we compare the fullerene emission to fluorescent and thermal models. In addition, the spectra show other interesting and common features, most notably in the 6-9um region, where a broad plateau with substructure dominates the emission. These features have previously been associated with mixtures of aromatic/aliphatic hydrocarbon solids. We hypothesize on the origin of this band, which is likely related to the fullerene formation mechanism, and compare it with modeled Hydrogenated Amorphous Carbon that present emission in this region.Comment: 13 pages, 2 tables, 7 figures, Accepted for publication in Ap

    Reconstrucción de rotura crónica de tendón distal del bíceps braquial: a propósito de un caso

    Get PDF
    Las roturas inveteradas o crónicas del tendón distal del bíceps braquial son infrecuentes. Su tratamiento supone un reto importante por el grado de retracción y deficiente calidad del tendón y músculo lesionados, que en ocasiones obligan al empleo de injertos para tratar de restaurar la anatomía y mejorar los resultados funcionales. La tasa de complicaciones en las reparaciones de roturas crónicas es mayor con respecto a las reparaciones de lesiones agudas. Presentamos el caso de una reparación quirúrgica de una rotura crónica de 3 meses de evolución mediante la utilización de aloinjerto liofilizado de Aquiles.Chronic or inveterate disruptions of the distal biceps brachii are uncommon. Treatment remains a major challenge by shrinkage and poor quality of the injured tendon and muscle, which sometimes require the use of grafts to try to restore the anatomy and improve the functional outcomes. The rate of complications in surgical treatment of chronic tears is more than the repairs of acute injuries. We report the case of a surgical reconstruction of a chronic tear three months of evolution using lyophilized Achilles allograft

    Herpetofauna en dos sitios en el municipio de Soto la Marina, Tamaulipas, México

    Get PDF
    We conducted a herpetofaunal study from November 2009 to July 2010 on the ranches El Herradero and San Jose de los Leones, both in the municipality of Soto la Marina, in the centraleastern part of the state of Tamaulipas, northeastern Mexico. Their location corresponds to a peninsula surrounded by the Laguna Madre. The objectives were to conduct a herpetological inventory and to determine the distribution of the species in the plant communities and the status of each species following the criteria of the NOM-059-SEMARNAT-2010. The information will be useful in delineating an area to set aside for conservation easement for the species. We followed the transect method described by Campbell & Christman (1982). We recorded 17 species: one anuran, one crocodile, six turtles, three lizards and six snakes. Of these, eight are new records for the municipality of Soto la Marina, 10 species are at risk, six are of special concern, three are threatened, and one is endangered. The ranches contain 34.69% of the herpetofauna species present in the municipality.Se realizó un estudio herpetofaunístico en los ranchos El Herradero y San José de los Leones ambos ubicados en el municipio de Soto la Marina, en la porción central-oriental del estado de Tamaulipas al Noreste de México. Estos predios se ubican en una forma de península rodeada por agua perteneciente a la Laguna Madre. Los objetivos fueron: realizar un inventario herpetológico, determinar la asociación de la herpetofauna con las comunidades vegetales y determinar el estatus de cada una de las especies de acuerdo a la NOM-059-SEMARNAT-2010. Lo anterior con la finalidad de que el área ocupada por los ranchos sea para establecer sitios de conservación como servidumbre ecológica de especies. Se siguió el muestreo de transectos descrito por Campbell & Christman (1982). El estudio se realizó desde noviembre de 2009 hasta julio de 2010. Se registraron 17 especies: un anuro, seis tortugas, un cocodrilo, tres lagartijas y seis serpientes. De estos, ocho son nuevos reportes para el municipio de Soto la Marina, y de acuerdo con la NOM-059-SEMARNAT-2010 se reportaron 10 especies donde seis se encuentran Sujetas a Protección Especial, tres se encuentran Amenazadas y una en Peligro de Extinción. Los ranchos cuentan con 34.69% de las especies de herpetofauna presente en el municipio

    Rotura bilateral y simultánea del tendón de Aquiles

    Get PDF
    La rotura bilateral y simultánea del tendón de Aquiles es un hecho excepcional. La producción de esta lesión en una persona joven, sin antecedentes patológicos ni de administración de ciertos medicamentos es aún más excepcional. El tratamiento quirúrgico y un adecuado proceso de seguimiento y rehabilitación contribuyen a una buena recuperación y pronóstico en los individuos jóvenes y activos con roturas del tendón de Aquiles. Se presenta un caso clínico de una mujer de 21 años tratada quirúrgicamente con buen resultado.The bilateral and simultaneous rupture of Achilles tendon is an excepcional situation. The production of this injury in a young person, without history pathological or administration of certain drugs is even more exceptional. The surgical treatment and a proper process of following-up and rehabilitation help to a good recovery and prognosis in young and active people with Achilles tendon ruptures

    Mitochondrial echoes of first settlement and genetic continuity in El Salvador

    Get PDF
    Background: From Paleo-Indian times to recent historical episodes, the Mesoamerican isthmus played an important role in the distribution and patterns of variability all around the double American continent. However, the amount of genetic information currently available on Central American continental populations is very scarce. In order to shed light on the role of Mesoamerica in the peopling of the New World, the present study focuses on the analysis of the mtDNA variation in a population sample from El Salvador. Methodology/Principal Findings: We have carried out DNA sequencing of the entire control region of the mitochondrial DNA (mtDNA) genome in 90 individuals from El Salvador. We have also compiled more than 3,985 control region profiles from the public domain and the literature in order to carry out inter-population comparisons. The results reveal a predominant Native American component in this region: by far, the most prevalent mtDNA haplogroup in this country (at ~90%) is A2, in contrast with other North, Meso- and South American populations. Haplogroup A2 shows a star-like phylogeny and is very diverse with a substantial proportion of mtDNAs (45%; sequence range 16090–16365) still unobserved in other American populations. Two different Bayesian approaches used to estimate admixture proportions in El Salvador shows that the majority of the mtDNAs observed come from North America. A preliminary founder analysis indicates that the settlement of El Salvador occurred about 13,400±5,200 Y.B.P.. The founder age of A2 in El Salvador is close to the overall age of A2 in America, which suggests that the colonization of this region occurred within a few thousand years of the initial expansion into the Americas. Conclusions/Significance: As a whole, the results are compatible with the hypothesis that today's A2 variability in El Salvador represents to a large extent the indigenous component of the region. Concordant with this hypothesis is also the observation of a very limited contribution from European and African women (~5%). This implies that the Atlantic slave trade had a very small demographic impact in El Salvador in contrast to its transformation of the gene pool in neighbouring populations from the Caribbean facade

    Influencia de la densidad de Odocoileus hemionus crooki Mearns, 1897, (Artiodactyla: Cervidae) en la abundancia relativa de puma Concolor stanleyana Goldman, 1938, (Carnivora: Felidae) y la relación en la depredación en una población reintroducida de Ovis canadensis mexicana Merriam, 1901, (Artiodactyla: Bovidae) en Coahuila, México

    Get PDF
    Translocations have been an important management tool for the restoration of bighorn sheep populations (Ovis canadensis mexicana Merriam, 1901) in their historical range in Canada, the United States and Mexico. Recent studies have suggested that puma (Puma concolor stanleyana Goldman, 1938) predation has important effects on population dynamics in reintroduced groups and native population of bighorn sheep in areas where it is sympatric with mule deer (Odocoileus hemionus crooki Mearns, 1897). Our hypothesis is that the size of the population of mule deer will determine the size of the population of the puma exerting a pressure on the population of the bighorn sheep. The study was based on 69 bighorn sheep (28 males, 41 females) captured using a hand-held net gun fired from a helicopter; 43 sheep (3 males, 40 females) were attached radio collars with mortality sensors and released in 3 periods between the years 2009, 2012 and 2014; we measure the puma predation on bighorn sheep with radio collar through MICROMORTS and the estimation of the density of mule deer through physical count of and relative puma abundance index through count tracks in the years of 2009 to 2016. We analyze the variables using a multiple regression model, finding an association between the variables and the pressure it exerts in the bighorn sheep population.Las translocaciones han sido una importante herramienta de manejo para la restauración de poblaciones de borrego cimarrón (Ovis canadensis mexicana Merriam, 1901) en su rango histórico en Canadá, Estados Unidos y México. Estudios recientes han sugerido que la depredación del puma (Puma concolor stanleyana Goldman, 1938) tiene importantes efectos sobre la dinámica poblacional en grupos reintroducidos y nativos de borrego cimarrón en áreas donde esta especie es simpátrica con venado bura (Odocoileus hemionus crooki Mearns, 1897). Nuestra hipótesis es que, el tamaño de la población de venado bura determinará el tamaño de la población de los pumas que a la vez ejercerá presión sobre la población del borrego cimarrón. El estudio se basó en el monitoreo de 69 borregos cimarrones (28 machos, 41 hembras) capturados con una la técnica de rifle red desde un helicóptero; 43 borregos (3 machos, 40 hembras) fueron equipados con radio collares con sensores de mortalidad y liberados en 3 períodos entre los años 2009, 2012 y 2014; medimos la depredación por puma sobre borrego cimarrón instrumentados con radio collares de telemetría a través de MICROMORTS y la estimación de la densidad del venado bura a través de conteos físicos e índice de relativa abundancia de puma por medio de huella y/o signos en los años de 2009 al 2016. Analizamos las variables mediante un modelo de regresión múltiple encontrando una asociación lineal entre las variables, y la presión que ejerce sobre la población de borrego cimarrón

    New Population and Phylogenetic Features of the Internal Variation within Mitochondrial DNA Macro-Haplogroup R0

    Get PDF
    BACKGROUND: R0 embraces the most common mitochondrial DNA (mtDNA) lineage in West Eurasia, namely, haplogroup H (approximately 40%). R0 sub-lineages are badly defined in the control region and therefore, the analysis of diagnostic coding region polymorphisms is needed in order to gain resolution in population and medical studies. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced the first hypervariable segment (HVS-I) of 518 individuals from different North Iberian regions. The mtDNAs belonging to R0 (approximately 57%) were further genotyped for a set of 71 coding region SNPs characterizing major and minor branches of R0. We found that the North Iberian Peninsula shows moderate levels of population stratification; for instance, haplogroup V reaches the highest frequency in Cantabria (north-central Iberia), but lower in Galicia (northwest Iberia) and Catalonia (northeast Iberia). When compared to other European and Middle East populations, haplogroups H1, H3 and H5a show frequency peaks in the Franco-Cantabrian region, declining from West towards the East and South Europe. In addition, we have characterized, by way of complete genome sequencing, a new autochthonous clade of haplogroup H in the Basque country, named H2a5. Its coalescence age, 15.6+/-8 thousand years ago (kya), dates to the period immediately after the Last Glacial Maximum (LGM). CONCLUSIONS/SIGNIFICANCE: In contrast to other H lineages that experienced re-expansion outside the Franco-Cantabrian refuge after the LGM (e.g. H1 and H3), H2a5 most likely remained confined to this area till present days

    Effects of mindfulness-based interventions on biomarkers and low-grade inflammation in patients with psychiatric disorders: A meta-analytic review

    Get PDF
    Mindfulness-Based Interventions (MBIs) present positive effects on mental health in diverse populations. However, the detailed associations between MBIs and biomarkers in patients with psychiatric disorders remain poorly understood. The aim of this study was to examine the effects of MBIs on biomarkers in psychiatric illness used to summarise the effects of low-grade inflammation. A systematic review of PubMed, EMBASE, PsycINFO, and the Cochrane Library was conducted. Effect sizes (ESs) were determined by Hedges’ g and the number needed to treat (NNT). Heterogeneity was evaluated. A total of 10 trials with 998 participants were included. MBIs showed significant improvements in the event-related potential amplitudes in attention-deficit hyperactivity disorder, the methylation of serotonin transporter genes in post-traumatic stress disorder, the salivary levels of interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-a) in depression, and the blood levels of adrenocorticotropic hormone (ACTH), IL-6, and TNF-a in generalised anxiety disorder. MBIs showed low but significant effects on health status related to biomarkers of low-grade inflammation (g = -0.21; 95% confidence interval (CI) –0.41 to -0.01; NNT = 8.47), with no heterogeneity (I2 = 0; 95% CI 0 to 79). More trials are needed to establish the impact of MBIs on biomarkers in psychiatric illness
    corecore