928 research outputs found
Generation of articial thermal sources and their characterization by intensity interferometry
The Hanbury Brown and Twiss (HB-T) effect is fundamental to understand the nature of light, with important applications, for instance in ghost imaging. In this work, some coherence properties of the light emitted by an artifificial source were investigated. In particular, the second-order coherence function in time was retrieved under different experimental conditions. The work included the generation of pseudothermal light by using distinct rotating diffusers. The emitters were then characterized by setting an intensity interferometer (also called Hanbury Brown-Twiss interferometer). This procedure allowed to measure the photon bunching, or equivalently whether and how photons were eventually grouped at the detector. The results showed that the variation of the rotation speed of the difuser played a role in the second-order temporal coherence function, particularly when low rotation speeds were considered
Comparación de los sistemas de transporte rápido de autobús articulado de México
Se abordan cuatro sistemas brt (por sus siglas en inglés de Bus Rapid Transit) de México: Metrobús de la Ciudad de México, Macrobús de la Ciudad de Guadalajara, Jalisco, Optibús de la Ciudad de León Guanajuato y Mexibús del Estado de México; con el fin de identificar sus características en cuanto a la tecnología, combustibles e infraestructura, para compararlos y determinar sus ventajas y desventajas tanto ambientales como operacionales. Con el objetivo de determinar cuál de estos sistemas está operando de manera óptima con respecto al cuidado del medio ambiente y al servicio de transporte.Se abordan cuatro sistemas brt (por sus siglas en inglés de Bus Rapid Transit) de México: Metrobús de la Ciudad de México, Macrobús de la Ciudad de Guadalajara, Jalisco, Optibús de la Ciudad de León Guanajuato y Mexibús del Estado de México; con el Àn de identiÀcar sus características en cuanto a la tecnología, combustibles e infraestructura, para compararlos y determinar sus ventajas y desventajas tanto ambientales como operacionales. Con el objetivo de determinar cuál de estos sistemas está operando de manera óptima con respecto al cuidado del medio ambiente y al servicio de transporte
Los terceros complejos: lacompetencia de la Jurisdicción Especial para la Paz, Resumen Ejecutivo
This is an executive summary of the policy paper "Los terceros complejos: lacompetencia de la Jurisdicción Especial para la Paz
Dual ultrahigh speed swept-source and time domain optical coherence tomography system using a time stretch laser and a KTN deflector
We present an ultrahigh-speed Swept Source Optical Coherence Tomography (SS-OCT) system that allows a volume rate of 400 Hz paired with a Time Domain (TD) subsystem. For the SS-OCT, a 40 MHz swept source is used, while for the TD-OCT, a broadband source. Both systems employ a scanning system that consists of a KTN scanner paired with a galvoscanner. The KTN crystal scans the beam laterally at 100 kHz. This allows B-scan OCT repetition rate, while with the galvoscanner 200 lines are obtained at 400 Hz in the en-face display of both SS-OCT and TD-OCT systems
The truncation of the disk of NGC 4565: Detected up to z=4 kpc, with star formation, and affected by the warp
Context: The hierarchical model of galaxy formation suggests that galaxies
are continuously growing. However, our position inside the Milky Way prevents
us from studying the disk edge. Truncations are low surface brightness features
located in the disk outskirts of external galaxies. They indicate where the
disk brightness abruptly drops and their location is thought to change
dynamically. In previous analyses of Milky Way-like galaxies, truncations were
detected up to 3 kpc above the mid-plane but whether they remain present beyond
that height remains unclear.
Aims: Our goal is to determine whether truncations can be detected above 3
kpc height in the Milky Way-like galaxy NGC 4565, thus establishing the actual
disk thickness. We also aim to study how the truncation relates to disk
properties such as star formation activity or the warp.
Methods: We perform a vertical study of the disk of NGC 4565 edge in
unprecedented detail. We explore the truncation radius at different heights
above/below the disk mid-plane (0<z<8 kpc) and at different wavelengths. We use
new ultra-deep optical data ( mag arcsec; within arcsec boxes) in the , and broad
bands, along with near- and far-ultraviolet, H, and \ion{H}{i}
observations.
Results: We detect the truncation up to 4 kpc in the , and
ultra-deep bands which is 1 kpc higher than in any previous study for any
galaxy. The radial position of the truncation remains constant up to 3 kpc
while higher up it is located at a smaller radius. This result is independent
of the wavelength but is affected by the presence of the warp.
Conclusions: We propose an inside-out growth scenario for the formation of
the disk of NGC 4565. Our results point towards the truncation feature being
linked to a star-forming threshold and to the onset of the disk warp.Comment: 27 pages, 18 figures (incl. 2 appendix); accepted for publication in
A&A; Fixed labels in Fig.
Propuesta de plan de mejoramiento de selección de radioperadores calificados para la categorización de los pacientes en la organización médica domiciliaria S.A.S – OMD
La atención médica domiciliaria, es un modelo de prestación de servicios de salud que se ha popularizado en los últimos años tanto a nivel mundial como en las principales ciudades de Colombia; considerada en la actualidad como un sistema innovador para resolver algunas necesidades en salud que pueda presentar un paciente, evitando trasladarse a un centro médico cuando se trata de patologías de baja complejidad o en algunos casos priorizando el nivel de atención que pueda requerir el usuario de acuerdo a su condición clínica.
El principal objetivo de este modelo es poder suplir las necesidades del cuidado y atención del paciente de manera integral y según la complejidad o abordaje que estos requieran, disminuyendo la necesidad de que el usuario llegue hasta un centro médico, clínica u hospital, igualmente disminuyendo la carga de cuidado para los familiares y los costos derivados de la atención intrahospitalaria y la exposición a presentar complicaciones asociadas al cuidado en salud que se presentan particularmente en el adulto mayor y en el enfermo crónico y/o con múltiples comorbilidades.EspecializaciónEspecialista En Gerencia De La Salu
Closure of a large lumbosacral myelomeningocele post operative defect with a human cadaveric split-thickness skin graft: a case report
Spina bifida is the most common birth defect of the central nervous system that is compatible with life, and myelomeningocele represents its most frequent form. Congenital myelomeningocele (CMM) has a worldwide incidence of 0.5 to 0.8 per 1,000 live newborns. CMM is a complex condition resulting from incomplete closure of the neural tube, mainly in the lumbosacral region. The objective of the surgical repair of the CMM is the reconstruction of all the tissue layers of the defect, avoiding possible postoperative complications. The aim of this case review is to present a re-epithelialization closure in a patient with a large CMM defect in who primary hermetic closure was not possible because there was too much tension at the edges of the defect. Therefore, human cadaveric split-thickness skin grafts were placed over the dura mater and the aponeurotic layer, covering the entire defect and an adequate healing and completely closure of the defect were observed in eight weeks. The surgical management of large meningomyelocele defects represents a major challenge and no single protocol exists for its reconstruction. The repair of an MMC defect should be performed during the first 72 hours after birth. After neurosurgical closure of the neural tube and dura, the myelomeningocele defect requires good quality skin and subcutaneous tissue with minimal wound tension for stable coverage. Human cadaveric skin grafts are considered a useful technique for temporary wound coverage because they lead to a more natural healing environment, possess ideal properties, and provide a physiological barrier that reduces microbiological contamination, in addition, it acts as a bridge to adhere to and to seal wound beds
Entre coaccion y colaboracion - verdad judicial, actores economicos y conflicto armado en Colombia
Paraneoplastic Cerebellar Degeneration Secondary to BRAF Mutant Melanoma Metastasis from an Occult Primary Cancer
Melanoma metastasis from an unknown primary cancer has an incidence of 3.2% among melanoma patients. Furthermore, paraneoplastic neurological syndromes (PNS) are rare, occurring in 1-3% of patients with malignancies. Paraneoplastic cerebellar degeneration (PCD) is one of the classic PNS and is characterized by acute or subacute onset of ataxia and/or presence of onconeural antibodies. A 61-year-old male with ataxia, vertigo, and headache later developed dysarthria, multidirectional nystagmus, hyperactive delirium, auditory hallucinations, psychomotor agitation, and myoclonus. Toxicological, metabolic, infectious, and autoimmune etiologies were assessed and reported negative. An osteolytic lesion was observed in the right iliac crest via computed tomography (CT). A positron emission tomography-CT reported increased fluorodeoxyglucose uptake of a right iliac and right inguinal ganglion. After biopsy of the right inguinal ganglion, a BRAF mutation-positive melanoma metastasis from an occult primary cancer was diagnosed. Dermatologic, ophthalmologic, and endoscopic gastrointestinal assessment did not reveal a primary malignant melanoma. The patient's movement disorders and neuropsychiatric symptoms improved with quetiapine, prednisone, azathioprine, and cyclophosphamide. Oncological management was conducted with MAPK pathway inhibitors (i.e., dabrafenib and trametinib). Movement disorders associated with neuropsychiatric symptoms are complex to diagnose. PNS are rare and often associated with antibodies against neural antigens expressed by the tumor. The case presented above describes a patient with a BRAF-positive malignant melanoma metastasis from an occult primary associated with PCD - to the best of our knowledge, the first reported in the literature.</p
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