626 research outputs found

    On the ongoing multiple blowout in NGC 604

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    Several facts regarding the structure of NGC 604 are examined here. The three main cavities, produced by the mechanical energy from massive stars which in NGC 604 are spread over a volume of 106^6 pc3^3, are shown here to be undergoing blowout into the halo of M33. High resolution long slit spectroscopy is used to track the impact from massive stars while HST archive data is used to display the asymmetry of the nebula. NGC 604 is found to be a collection of photoionized filaments and sections of shells in direct contact with the thermalized matter ejected by massive stars. The multiple blowout events presently drain the energy injected by massive stars and thus the densest photoionized gas is found almost at rest and is expected to suffer a slow evolution.Comment: 15 pages (11 text), 4 figures. To be published in Ap

    On the feedback from super stellar clusters. I. The structure of giant HII regions and HII galaxies

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    We review the structural properties of giant extragalactic HII regions and HII galaxies based on 2D hydrodynamic calculations, and propose an evolutionary sequence that accounts for their observed detailed structure. The model assumes a massive and young stellar cluster surrounded by a large collection of clouds. These are thus exposed to the most important star-formation feedback mechanisms: photoionization and the cluster wind. The models show how the two feedback mechanisms compete in the disruption of clouds and lead to two different hydrodynamic solutions: The storage of clouds into a long lasting ragged shell that inhibits the expansion of the thermalized wind, and the steady filtering of the shocked wind gas through channels carved within the cloud stratum. Both solutions are claimed to be concurrently at work in giant HII regions and HII galaxies, causing their detailed inner structure. This includes multiple large-scale shells, filled with an X-ray emitting gas, that evolve to finally merge with each other, giving the appearance of shells within shells. The models also show how the inner filamentary structure of the giant superbubbles is largely enhanced with matter ablated from clouds and how cloud ablation proceeds within the original cloud stratum. The calculations point at the initial contrast density between the cloud and the intercloud media as the factor that defines which of the two feedback mechanisms becomes dominant throughout the evolution. Animated version of the models can be found at http://www.iaa.csic.es/\~{}eperez/ssc/ssc.html.Comment: 28 pages, 10 figures, accepted for publication in the ApJ. Animated version of the models can be found at http://www.iaa.csic.es/\~{}eperez/ssc/ssc.htm

    “CALIDAD DE LA ANESTESIA GENERAL ENDOVENOSA EN PACIENTES SOMETIDAS A LUI EN EL HOSPITAL MUNICIPAL HUEHUETOCA, ISEM.,2013.

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    Objetivo: Determinar la calidad de la anestesia empleada en pacientes sometidas a Legrado Uterino Instrumental en el Hospital Municipal Huehuetoca. Diseño de estudio: El presente trabajo de investigación es de tipo descriptivo, observacional, retrospectivo y transversal. Resultados: En el periodo comprendido de Enero del 2011 a Mayo del 2012, se realizaron 62 legrados uterinos instrumentales bajo Anestesia General Endovenosa, de las cuales el 35.4% fue de 19 a 23 años, el 40.3% fluctúan en un peso de 51-60 kg, los analgésicos narcóticos utilizados fueron nalbufina 75.8% y fentanyl 24.1%, la utilización de benzodiacepinas fue midazolam 24.1%, diacepam 6.4%, sin benzodiacepinas 69.3%. Los inductores aplicados fueros propofol 90.3%, ketamina 8% y etomidato 2.6%. No se presentados complicaciones propias de la técnica anestésica. La calidad de la técnica anestésica fue buena en el 91.9% y regular en 8.1%. El riesgo anestésico ASA I fue el de mayor prevalencia con un 88.7%. El diagnostico más frecuente fue aborto incompleto con un 69.3%. Conclusiones: Con base a lo anterior se concluye que en el Hospital Municipal Huehuetoca se otorga anestesia general endovenosa para legrados uterinos instrumentales de calidad y con amplio estándar de seguridad haciendo hincapié que la actualización del médico anestesiólogo es importante para complementar la anestesia segura y de calida

    Implementación de Lean Manufacturing en el área de producción para aumentar la productividad en Inversiones Liber San Luis, 2022

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    Esta investigación estuvo basada en Determinar cómo la implementación de Lean Manufacturing aumenta la productividad, en el área de producción, Inversiones Liber San Luis 2022 en función del objetivo general, la investigación tuvo un enfoque cuantitativo, de tipo aplicada y con un diseño pre experimental, con un alcance transversal. Las técnicas que fueron empleados para el recojo de información fueron: la entrevista y la encuesta en conjunto con la data de la producción. Con la implementación Lean, se logró obtener los siguientes resultados. Con la 5S, se logró aumentar el nivel de cumplimiento de 40% a 75% posterior a ella, Con la herramienta Smed, se logró obtener lo siguiente en disponibilidad de tiempo de 76% a 82% con una disponibilidad del 8% y para la herramienta Tpm, se logró obtener una mejor disponibilidad a través de su indicador OEE de un 50% a 76 % posterior a la implementación. Se realizo la prueba de t – student para la constatación y validación de hipótesis, del cual se obtuvo un nivel de 0000012 por lo que se logra su aceptación. Como conclusión se logró determinar que las herramientas Lean, aumentaron la productividad del área de producción de la empresa en un 20%

    Enteroviruses in Spain: virological and epidemiological studies over 10 years (1988-97)

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    A total of 15,662 clinical samples were analysed for enterovirus (EV) isolation in cell cultures during a 10-year period (1988-97). Furthermore, 210 isolates of EV obtained in primary laboratories within Spain from patients with meningitis were characterized. The total number of EV typed was 758, including 727 non-polio EV and 31 Sabin-like (SL) polioviruses. Twenty-eight EV serotypes were represented. Echoviruses comprised 90% (653/727) of fully typed non-polio EV. The four most prevalent serotypes were echovirus 30, echovirus 9, echovirus 6 and echovirus 4. Echovirus 30 was the main serotype associated with meningitis. Echovirus 9 was the aetiological agent in 20 outbreaks of meningitis while the occurrence of echovirus 6 was localized in 1 year (1997). Coxsackieviruses A and B occurred in 3 and 7% of the non-polio EV respectively. Coxsackievirus B5 presented the relative greater abundance. This paper examines the epidemiology of EV in Spain to serotype level over a 10-year period with special attention to non-polio EV associated with meningitis.Dr I. Casas is a postdoctoral fellow supported by the Institute de Salud Carlos III, Becas de Perfeccionamiento (97/4165). We acknowledge the assistance provided by clinical colleagues in other virology laboratories: Gurutze Rubio (Cruces, Bilbao, Hospital), Nuria Rabella (Santa Cruz y San Pablo, Barcelona Hospital), Joaquin Otero (Doce de Octubre, Madrid Hospital). We also thank Raquel Noguerol, Hortensia del Pozo and Isidoro Bustillo for their technical assistance and an anonymous referee for many useful suggestions. This work was partially supported by Fondo de Investigación Sanitaria grant FIS 96/0304.S

    Integrability of the Gross-Pitaevskii Equation with Feshbach Resonance management

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    In this paper we study the integrability of a class of Gross-Pitaevskii equations managed by Feshbach resonance in an expulsive parabolic external potential. By using WTC test, we find a condition under which the Gross-Pitaevskii equation is completely integrable. Under the present model, this integrability condition is completely consistent with that proposed by Serkin, Hasegawa, and Belyaeva [V. N. Serkin et al., Phys. Rev. Lett. 98, 074102 (2007)]. Furthermore, this integrability can also be explicitly shown by a transformation, which can convert the Gross-Pitaevskii equation into the well-known standard nonlinear Schr\"odinger equation. By this transformation, each exact solution of the standard nonlinear Schr\"odinger equation can be converted into that of the Gross-Pitaevskii equation, which builds a systematical connection between the canonical solitons and the so-called nonautonomous ones. The finding of this transformation has a significant contribution to understanding the essential properties of the nonautonomous solitions and the dynamics of the Bose-Einstein condensates by using the Feshbach resonance technique.Comment: 13 page

    Unraveling the antiviral activity of plitidepsin against SARS-CoV-2 by subcellular and morphological analysis

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    The pandemic caused by the new coronavirus SARS-CoV-2 has made evident the need for broad-spectrum, efficient antiviral treatments to combat emerging and re-emerging viruses. Plitidepsin is an antitumor agent of marine origin that has also shown a potent pre-clinical efficacy against SARS-CoV-2. Plitidepsin targets the host protein eEF1A (eukaryotic translation elongation factor 1 alpha) and affects viral infection at an early, post-entry step. Because electron microscopy is a valuable tool to study virus-cell interactions and the mechanism of action of antiviral drugs, in this work we have used transmission electron microscopy (TEM) to evaluate the effects of plitidepsin in SARS-CoV-2 infection in cultured Vero E6 cells 24 and 48h post-infection. In the absence of plitidepsin, TEM morphological analysis showed double-membrane vesicles (DMVs), organelles that support coronavirus genome replication, single-membrane vesicles with viral particles, large vacuoles with groups of viruses and numerous extracellular virions attached to the plasma membrane. When treated with plitidepsin, no viral structures were found in SARS-CoV-2-infected Vero E6 cells. Immunogold detection of SARS-CoV-2 nucleocapsid (N) protein and double-stranded RNA (dsRNA) provided clear signals in cells infected in the absence of plitidepsin, but complete absence in cells infected and treated with plitidepsin. The present study shows that plitidepsin blocks the biogenesis of viral replication organelles and the morphogenesis of virus progeny. Electron microscopy morphological analysis coupled to immunogold labeling of SARS-CoV-2 products offers a unique approach to understand how antivirals such as plitidepsin work.info:eu-repo/semantics/publishedVersio

    Ten Million Degree Gas in M 17 and the Rosette Nebula: X-ray Flows in Galactic H II Regions

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    We present the first high-spatial-resolution X-ray images of two high-mass star forming regions, the Omega Nebula (M 17) and the Rosette Nebula (NGC 2237--2246), obtained with the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer (ACIS) instrument. The massive clusters powering these H II regions are resolved at the arcsecond level into >900 (M 17) and >300 (Rosette) stellar sources similar to those seen in closer young stellar clusters. However, we also detect soft diffuse X-ray emission on parsec scales that is spatially and spectrally distinct from the point source population. The diffuse emission has luminosity L_x ~ 3.4e33 ergs/s in M~17 with plasma energy components at kT ~0.13 and ~0.6 keV (1.5 and 7 MK), while in Rosette it has L_x \~6e32 ergs/s with plasma energy components at kT ~0.06 and ~0.8 keV (0.7 and 9 MK). This extended emission most likely arises from the fast O-star winds thermalized either by wind-wind collisions or by a termination shock against the surrounding media. We establish that only a small portion of the wind energy and mass appears in the observed diffuse X-ray plasma; in these blister H II regions, we suspect that most of it flows without cooling into the low-density interstellar medium. These data provide compelling observational evidence that strong wind shocks are present in H II regions.Comment: 35 pages, including 11 figures; to appear in ApJ, August 20, 2003. A version with high-resolution figures is available at ftp://ftp.astro.psu.edu/pub/townsley/diffuse.ps.g

    Mutations in SCNM1 cause orofaciodigital syndrome due to minor intron splicing defects affecting primary cilia

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    Orofaciodigital syndrome (OFD) is a genetically heterogeneous ciliopathy characterized by anomalies of the oral cavity, face, and digits. We describe individuals with OFD from three unrelated families having bi-allelic loss-of-function variants in SCNM1 as the cause of their condition. SCNM1 encodes a protein recently shown to be a component of the human minor spliceosome. However, so far the effect of loss of SCNM1 function on human cells had not been assessed. Using a comparative transcriptome analysis between fibroblasts derived from an OFD-affected individual harboring SCNM1 mutations and control fibroblasts, we identified a set of genes with defective minor intron (U12) processing in the fibroblasts of the affected subject. These results were reproduced in SCNM1 knockout hTERT RPE-1 (RPE-1) cells engineered by CRISPR-Cas9-mediated editing and in SCNM1 siRNA-treated RPE-1 cultures. Notably, expression of TMEM107 and FAM92A encoding primary cilia and basal body proteins, respectively, and that of DERL2, ZC3H8, and C17orf75, were severely reduced in SCNM1-deficient cells. Primary fibroblasts containing SCNM1 mutations, as well as SCNM1 knockout and SCNM1 knockdown RPE-1 cells, were also found with abnormally elongated cilia. Conversely, cilia length and expression of SCNM1-regulated genes were restored in SCNM1-deficient fibroblasts following reintroduction of SCNM1 via retroviral delivery. Additionally, functional analysis in SCNM1-retrotransduced fibroblasts showed that SCNM1 is a positive mediator of Hedgehog (Hh) signaling. Our findings demonstrate that defective U12 intron splicing can lead to a typical ciliopathy such as OFD and reveal that primary cilia length and Hh signaling are regulated by the minor spliceosome through SCNM1 activity.This work was supported by a grant from the Spanish Ministry of Science and Innovation (PID2019-105620RB-I00/AEI/10.13039/501100011033)

    Treating breast cancer through novel inhibitors of the phosphatidylinositol 3'-kinase pathway

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    Recent studies indicate that constitutive signaling through the phosphatidylinositol 3'-kinase (PI3K) pathway is a cause of treatment resistance in breast cancer patients. This implies that patients with tumors that exhibit aberrant PI3K signaling may benefit from targeted pathway inhibitors. The first agents to make it to the clinic are the rapamycin analogs. These compounds inhibit the downstream PI3K effector mTOR (mammalian target of rapamycin). A study presented in this issue of Breast Cancer Research suggests that recently developed inhibitors of phosphoinositide-dependent protein kinase 1, a more proximal target of the PI3K pathway, may provide an alternative route to effective PI3K pathway inhibition for breast cancer treatment
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