An XMM-Newton observation of the globular cluster Omega Centauri

We report on a deep XMM-Newton EPIC observation of the globular cluster Omega Cen performed on August 13th, 2001. We have detected 11 and 27 faint X-ray sources in the core and half mass radii, searching down to a luminosity of 1.3 x 10^{31} erg s^{-1} in the 0.5-5 keV range. Most sources have bolometric X-ray luminosities between ~ 10^{31}-10^{32} erg s^{-1}. We present the color-color and hardness-intensity diagrams of the source sample, as well as high-quality EPIC spectra of the brightest objects of the field; including the two candidate Cataclysmic Variables (CVs) in the core and the quiescent neutron star low-mass X-ray binary candidate. The spectra of the latter objects fully support their previous classification. We show that the bulk of sources are hard and spectrally similar to CVs. The lack of soft faint sources might be related to the absence of millisecond pulsars in the cluster. The XMM-Newton observations reveal the presence of an excess of sources well outside the core of the cluster where several RS CVn binaries have already been found. We have also analyzed a publicly available Chandra ACIS-I observation performed on January 24-25th, 2000, to improve the XMM-Newton source positions and to search for source intensity variations between the two data sets. 63 XMM-Newton sources have a Chandra counterpart, and 15 sources within the half-mass radius have shown time variability. Overall, the general properties of the faint X-ray sources in Omega Cen suggest that they are predominantly CVs and active binaries (RS CVn or BY Dra).Comment: 21 pages, 2 color figures, 8 B&W figures. Accepted for publication in Astronomy and Astrophysic

Orrouy – Champlieu

Identifiant de l'opération archéologique : 9246 Date de l'opération : 2007 (SD) Deux zones du site ont été sondées. Le premier sondage dans la supposée basilique (A-2007) s’est révélé négatif. Le second, implanté dans le couloir du porticus post scaenam(B et C-2007), a permis de réexhumer un bloc calcaire identifié comme le montant de l'entrée monumentale du probable portique mis en évidence en 2005. Il a également révélé en relation avec la summa cavea, le plancher intérieur du portique fo..

Orrouy – Champlieu

Identifiant de l'opération archéologique : 8934 Date de l'opération : 2006 (SD) En 2006, l'exploration du théâtre et de la zone urbaine comprise entre le théâtre et la zone sacrée s'est poursuivie. La tentative pour vérifier l'existence d'un propylée symétrique correspondant à l'entrée occidentale du couloir de la summa cavean’a pas abouti. Le sondage E - 2006, n’a livré que des restes de maçonnerie bouleversés (US 155) correspondant à des blocs quadrangulaires peut-être utilisés comme bases ..

Orrouy – Champlieu

Identifiant de l'opération archéologique : 8934 Date de l'opération : 2006 (SD) En 2006, l'exploration du théâtre et de la zone urbaine comprise entre le théâtre et la zone sacrée s'est poursuivie. La tentative pour vérifier l'existence d'un propylée symétrique correspondant à l'entrée occidentale du couloir de la summa cavean’a pas abouti. Le sondage E - 2006, n’a livré que des restes de maçonnerie bouleversés (US 155) correspondant à des blocs quadrangulaires peut-être utilisés comme bases ..

Creación de una empresa de transporte de pasajeros con una aplicación movil para comunas aledañas a Santiago

Tesis (Ingeniero Civil Industrial)El transporte público en la región metropolitana está cubierto mayormente por el sistema de transporte “Transantiago” el cual abastece a una gran cantidad de comunas de la región con el sistema de transporte. Actualmente 18 comunas de la región metropolitana no están cubiertas por el sistema de transporte “Transantiago”, donde el sistema de transporte es ofrecido por distintas empresas ,por ejemplo: Flota Talagante ,Bupesa ,Islaval, Buses Ruta 78 entre otras, las cuales monopolizan el mercado del transporte en estas comunas y establecen sus propias reglas para emplear en el sistema de transporte que ellos ofrecen a la comunidad, estableciendo el costo de los pasajes, los tiempos del servicio y los recorridos siendo los pasajeros obligados a utilizar estos servicios, ya que no existe una alternativa de viaje para ellos . En los últimos años estas empresas han presentado un gran déficit para satisfacer la demanda de viajes de todos los ciudadanos, llegando al punto del colapso del sistema el cual tiene a los pasajeros sin una solución por lo ofrecido actualmente por estas empresas las cuales no entregan ninguna solución.Por esto todos los años aumenta la necesidad de traslado de personas de comunas aledañas a Santiago y estas zonas al no estar cubiertas por el transantiago están obligadas al uso de otras empresas de trasporte, existen servicios los cuales ofrecen este tipo de viajes, pero estos no son capaces de cubrir la demanda y no entregan un servicio de calidad por ejemplo buses en mal estado, inseguridad en los viajes, sobrecarga de buses, largos tiempos de espera, malos tratos de los choferes, alza de precios sin justificación entre otros, causando una desaprobación de parte de los clientes, los cuales al no tener una alternativa distinta están obligados a utilizar estos servicios. Dentro de este contexto el proyecto consta en crear una empresa de servicio de pasajeros de las comunas antes mencionadas a Santiago, realizando estos viajes a través de autos particulares los cuales diariamente se dirigen a Santiago, con el fin de no insertar nuevos automóviles al parque automotriz de Santiago el cual esta sobrepoblado. La idea es reclutar a estos vehículos para que mediante una aplicación móvil ofrezcan a los clientes los distintos viajes con el costo asociado y el punto de reunión de los pasajeros.Al crear esta empresa de servicio de transporte y que esta sea gestionada a través de una aplicación móvil, se busca entregar una alternativa distinta a los clientes que necesitan trasladarse diariamente de estas comunas a Santiago, con el fin de entregar un servicio de calidad, cómodo el cual permita al pasajero realizar este viajes de manera más agradable dejando atrás filas interminables en las estaciones de buses y viajes de larga duración. Se pretende obtener rentabilidad en este proyecto a través de la gestión de estos viajes obteniendo un porcentaje de lo remunerado por cada vehículo particular al realizar uno de estos viajes y también a través de propaganda a través de la aplicación

Higher levels of glutamate in the associative-striatum of subjects with prodromal symptoms of schizophrenia and patients with first-episode psychosis

The glutamatergic and dopaminergic systems are thought to be involved in the pathophysiology of schizophrenia. Their interaction has been widely documented and may have a role in the neurobiological basis of the disease. The aim of this study was to compare, using proton magnetic resonance spectroscopy (1H-MRS), glutamate levels in the precommissural dorsal-caudate (a dopamine-rich region) and the cerebellar cortex (negligible for dopamine) in the following: (1) 18 antipsychotic-naïve subjects with prodromal symptoms and considered to be at ultra high-risk for schizophrenia (UHR), (2) 18 antipsychotic-naïve first- episode psychosis patients (FEP), and (3) 40 age- and sex- matched healthy controls. All subjects underwent a 1H-MRS study using a 3Tesla scanner. Glutamate levels were quantified and corrected for the proportion of cerebrospinal fluid and percentage of gray matter in the voxel. The UHR and FEP groups showed higher levels of glutamate than controls, without differences between UHR and FEP. In the cerebellum, no differences were seen between the three groups. The higher glutamate level in the precommissural dorsal-caudate and not in the cerebellum of UHR and FEP suggests that a high glutamate level (a) precedes the onset of schizophrenia, and (b) is present in a dopamine-rich region previously implicated in the pathophysiology of schizophrenia.peer-reviewe

Alopecia in Patients with Collagen VI-Related Myopathies: A Novel/Unrecognized Scalp Phenotype

Collagen VI-related myopathies are characterized by severe muscle involvement and skin involvement (keratosis pilaris and impaired healing with the development of abnormal scars, especially keloids). Scalp involvement and hair loss have not been reported among cutaneous changes associated with collagen VI mutations. The aim of this study is to describe the clinical, trichoscopic, and histological findings of the scalp changes in patients affected by COL VI mutations and to estimate their prevalence. Patients with Ullrich congenital muscular dystrophy were enrolled and underwent clinical and trichoscopic examinations and a scalp biopsy for histopathology. Five patients were enrolled, and all complained of hair loss and scalp itching. One patient showed yellow interfollicular scales with erythema and dilated, branched vessels, and the histological findings were suggestive of scalp psoriasis. Two patients presented with scarring alopecia patches on the vertex area, and they were histologically diagnosed with folliculitis decalvans. The last two patients presented with scaling and hair thinning, but they were both diagnosed with folliculitis and perifolliculitis. Ten more patients answered to a “scalp involvement questionnaire”, and six of them confirmed to have or have had scalp disorders and/or itching. Scalp involvement can be associated with COL VI mutations and should be investigated

Regulation of Intestinal Immune Response by Selective Removal of the Anterior, Posterior, or Entire Pituitary Gland in Trichinella spiralis Infected Golden Hamsters

The influence of anterior pituitary hormones on the gastrointestinal tract of humans and animals has been previously reported. Hypophysectomy (HYPOX) in the rat causes atrophy of the intestinal mucosa, and reduction of gastric secretion and intestinal absorption, as well as increased susceptibility to bacterial and viral infections. However, to our knowledge, no findings have been published concerning the immune response following HYPOX during worm infection, particularly that which is caused by the nematode Trichinella spiralis. The aim of this work was to analyze the effects of total or partial HYPOX on colonization of T. spiralis in the intestinal lumen, together with duodenal and splenic cytokine expression. Our results indicate that 5 days post infection, only neurointermediate pituitary lobectomy (NIL) reduces the number of intestinally recovered T. spiralis larvae. Using semiquantitative inmunofluorescent laser confocal microscopy, we observed that the mean intensity of all tested Th1 cytokines was markedly diminished, even in the duodenum of infected controls. In contrast, a high level of expression of these cytokines was noted in the NIL infected hamsters. Likewise, a significant decrease in the fluorescence intensity of Th2 cytokines (with the exception of IL-4) was apparent in the duodenum of control and sham infected hamsters, compared to animals with NIL surgeries, which showed an increase in the expression of IL-5 and IL-13. Histology of duodenal mucosa from NIL hamsters showed an exacerbated inflammatory infiltrate located along the lamina propria, which was related to the presence of the parasite. We conclude that hormones from each pituitary lobe affect the gastrointestinal immune responses to T. spiralis through various mechanisms