RESUMEN: El objetivo de este trabajo es identificar los rituales para la protección de animales domésticos criados en los solares de Yaxcabá y Yaxunah, Yucatán, México. En el solar se crían ...especialmente animales domésticos (gallinas, pavos y cerdos), los cuales son un elemento importante para las familias campesinas. Esta fauna forma parte de la economía, la alimentación cotidiana y son parte de las ofrendas en los festejos, las ceremonias y los rituales que dan continuidad a la vida familiar y comunal. Los resultados muestran que las familias católicas de Yaxcabá y Yaxunah continúan realizando ceremonias como el k’eex loj o loj k’eex, el loj, el jets’ lu’um y las primicias de saka’ (bebida sagrada de maíz). La finalidad de estas ceremonias es mantener una relación de reciprocidad con los dueños de la naturaleza por el uso de los recursos, lo cual favorece una relación de equilibrio con los mismos; de esta manera los dueños cuidarán todo el solar y a los habitantes de este espacio. Los integrantes de la familia y los animales criados se salvaguardan de los malos vientos o k’as k’aas íik’, causantes de enfermedades y calamidades. Este estudio destaca la visión del mundo que aún persiste en las comunidades mayas peninsulares, se conservan conocimientos y prácticas bioculturales que muestran las formas particulares de relacionarse con la naturaleza. Se analizan los conocimientos sobre los rituales que tienen los propietarios del solar y un especialista ritual, llamado espiritista.
Resumen Introducción La hipertensión intracraneal idiopática es una entidad caracterizada por el aumento de la presión intracraneal sin evidencias de proceso expansivo intracraneal o alteraciones ...citoquímicas del líquido cefalorraquídeo. Pacientes y método Se revisaron las historias clínicas de los pacientes con hipertensión intracraneal idiopática ingresados en nuestro hospital entre 1999 y 2009, y que cumplían los criterios modificados de Dandy. Se recogieron datos de edad, índice de masa corporal (IMC), presión de salida de líquido cefalorraquídeo, antecedentes cardiovasculares, pruebas de imagen, tratamiento y evolución. Resultados Se analizaron 61 pacientes (19 hombres y 42 mujeres), con una media de edad de 35,38 años. El 72,13% de los pacientes mostraban aumento del IMC. Cabe destacar que el 47,37% de los varones mostraban normopeso. El 50% de los pacientes presentaban algún factor de riesgo cardiovascular, destacando la dislipidemia, la hipertensión arterial y el tratamiento con anticonceptivos en las mujeres. La cefalea era el principal síntoma de presentación, seguido de las alteraciones campimétricas y otros defectos visuales. El 81,96% de los pacientes presentaban edema de papila bilateral. Conclusiones La incidencia aproximada es de 1,2/100.000 habitantes/año, siendo más frecuente en mujeres jóvenes que con aumento de peso y asociado a la toma de tratamiento anticonceptivo. Destaca la cefalea, con edema de papila bilateral y alteraciones de la agudeza visual como síntomas principales. Un dato interesante aportado por este trabajo es el menor IMC que se muestra en el sexo masculino, así como la menor presencia de cefalea y mayor afectación visual.
ABSTRACT Star formation is primarily controlled by the interplay between gravity, turbulence, and magnetic fields. However, the turbulence and magnetic fields in molecular clouds near the Galactic ...center may differ substantially compared to spiral-arm clouds. Here we determine the physical parameters of the central molecular zone (CMZ) cloud G0.253+0.016, its turbulence, magnetic field, and filamentary structure. Using column density maps based on dust-continuum emission observations with ALMA+Herschel, we identify filaments and show that at least one dense core is located along them. We measure the filament width and the sonic scale of the turbulence, and find . A strong velocity gradient is seen in the HNCO intensity-weighted velocity maps obtained with ALMA+Mopra. The gradient is likely caused by large-scale shearing of G0.253+0.016, producing a wide double-peaked velocity probability distribution function (PDF). After subtracting the gradient to isolate the turbulent motions, we find a nearly Gaussian velocity PDF typical for turbulence. We measure the total and turbulent velocity dispersion, and , respectively. Using magnetohydrodynamical turbulence simulations, we find that G0.253+0.016's turbulent magnetic field is only of the ordered field component. Combining these measurements, we reconstruct the dominant turbulence driving mode in G0.253+0.016 and find a driving parameter of , indicating solenoidal (divergence-free) driving. We compare this to spiral-arm clouds, which typically have a significant compressive (curl-free) driving component ( ). Motivated by previous reports of strong shearing motions in the CMZ, we speculate that shear causes the solenoidal driving in G0.253+0.016 and show that this reduces the star-formation rate by a factor of 6.9 compared to typical nearby clouds.
ABSTRACT G0.253+0.016 is a molecular clump that appears to be on the verge of forming a high-mass cluster: its extremely low dust temperature, high mass, and high density, combined with its lack of ...prevalent star formation, make it an excellent candidate for an Arches-like cluster in a very early stage of formation. Here we present new Atacama Large Millimeter/Sub-millimeter Array observations of its small-scale (∼0.07 pc) 3 mm dust continuum and molecular line emission from 17 different species that probe a range of distinct physical and chemical conditions. The data reveal a complex network of emission features with a complicated velocity structure: there is emission on all spatial scales, the morphology of which ranges from small, compact regions to extended, filamentary structures that are seen in both emission and absorption. The dust column density is well traced by molecules with higher excitation energies and critical densities, consistent with a clump that has a denser interior. A statistical analysis supports the idea that turbulence shapes the observed gas structure within G0.253+0.016. We find a clear break in the turbulent power spectrum derived from the optically thin dust continuum emission at a spatial scale of ∼0.1 pc, which may correspond to the spatial scale at which gravity has overcome the thermal pressure. We suggest that G0.253+0.016 is on the verge of forming a cluster from hierarchical, filamentary structures that arise from a highly turbulent medium. Although the stellar distribution within high-mass Arches-like clusters is compact, centrally condensed, and smooth, the observed gas distribution within G0.253+0.016 is extended, with no high-mass central concentration, and has a complex, hierarchical structure. If this clump gives rise to a high-mass cluster and its stars are formed from this initially hierarchical gas structure, then the resulting cluster must evolve into a centrally condensed structure via a dynamical process.
Despite the simplicity of theoretical models of supersonically turbulent, isothermal media, their predictions successfully match the observed gas structure and star formation activity within ...low-pressure (P/k < 10 super(5) K cm super(-3)) molecular clouds in the solar neighborhood. However, it is unknown whether or not these theories extend to clouds in high-pressure (P/k > 10 super(7)K cm super(-3)) environments, like those in the Galaxy's inner 200 pc central molecular zone (CMZ) and in the early universe. Here, we present Atacama Large Millimeter/submillimeter Array 3 mm dust continuum emission within a cloud, GO.253+0.016, which is immersed in the high-pressure environment of the CMZ. While the log-normal shape and dispersion of its column density probability distribution function (PDF) are strikingly similar to those of solar neighborhood clouds, there is one important quantitative difference: its mean column density is one to two orders of magnitude higher. Both the similarity and difference in the PDF compared to those derived from solar neighborhood clouds match predictions of turbulent cloud models given the high-pressure environment of the CMZ. The PDF shows a small deviation from log-normal at high column densities confirming the youth of GO.253+0.016. Its lack of star formation is consistent with the theoretically predicted, environmentally dependent volume density threshold for star formation which is orders of magnitude higher than that derived for solar neighborhood clouds. Our results provide the first empirical evidence that the current theoretical understanding of molecular cloud structure derived from the solar neighborhood also holds in high-pressure environments. We therefore suggest that these theories may be applicable to understand star formation in the early universe.
Recently, a comparison between the locations of 6.7-GHz methanol masers and dust continuum emission has renewed speculation that these masers can be associated with evolved stars. The implication of ...such a scenario would be profound, especially for the interpretation of large surveys for 6.7-GHz masers, individual studies where high-mass star formation has been inferred from the presence of 6.7-GHz methanol masers and for the pumping mechanisms of these masers. We have investigated the two instances where 6.7-GHz methanol masers have been explicitly suggested to be associated with evolved stars, and we find the first to be associated with a standard high-mass star formation region, and the second to be a spurious detection. We also find no evidence to suggest that the methanol maser action can be supported in the environments of evolved stars. We thereby confirm their exclusive association with high-mass star formation regions.
Using molecular line data from the Millimetre Astronomy Legacy Team 90 GHz Survey, we have searched the optically thick HCO+ (1-0) line for the "blue asymmetry" spectroscopic signature of infall ...motion in a large sample of high-mass, dense molecular clumps observed to be at different evolutionary stages of star cluster formation according to their mid-infrared appearance. To quantify the degree of the line asymmetry, we measure the asymmetry parameter , the fraction of the integrated intensity that lies to the blueshifted side of the systemic velocity determined from the optically thin tracer N2H+ (1-0). For a sample of 1093 sources, both the mean and median of A are positive ( and 0.065 0.009, respectively) with high statistical significance, and a majority of sources (a fraction of 0.607 0.015 of the sample) show positive values of A, indicating a preponderance of blue asymmetric profiles over red asymmetric profiles. Two other measures, the local slope of the line at the systemic velocity and the δv parameter of Mardones et al. (1997), also show an overall blue asymmetry for the sample, but with smaller statistical significance. This blue asymmetry indicates that these high-mass clumps are predominantly undergoing gravitational collapse. The blue asymmetry is larger ( ) for the earliest evolutionary stages (quiescent, protostellar, and compact H ii region) than for the later H ii region ( ) and photodissociation region ( ) classifications.
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