Bayesian Methods for Radiometric Calibration in Motion Picture Encoding Workflows

A method for estimating the Camera Response Function (CRF) of an electronic motion picture camera is presented in this work. The accurate estimation of the CRF allows for proper encoding of camera exposures into motion picture post-production workflows, like the Academy Color Encoding Specification (ACES), this being a necessary step to correctly combine images from different capture sources into one cohesive final production and minimize non-creative manual adjustments. Although there are well known standard CRFs implemented in typical video camera workflows, motion picture workflows and newer High Dynamic Range (HDR) imaging workflows have introduced new standard CRFs as well as custom and proprietary CRFs that need to be known for proper post-production encoding of the camera footage. Current methods to estimate this function rely on the use of measurement charts, using multiple static images taken under different exposures or lighting conditions, or assume a simplistic model of the function’s shape. All these methods become problematic and tough to fit into motion picture production and post-production workflows where the use of test charts and varying camera or scene setups becomes impractical and where a method based solely on camera footage, comprised of a single image or a series of images, would be advantageous. This work presents a methodology initially based on the work of Lin, Gu, Yamazaki and Shum that takes into account edge color mixtures in an image or image sequence, that are affected by the non-linearity introduced by a CRF. In addition, a novel feature based on image noise is introduced to overcome some of the limitations of edge color mixtures. These features provide information that is included in the likelihood probability distribution in a Bayesian framework to estimate the CRF as the expected value of a posterior probability distribution, which is itself approximated by a Markov Chain Monte Carlo (MCMC) sampling algorithm. This allows for a more complete description of the CRF over methods like Maximum Likelihood (ML) and Maximum A Posteriori (MAP). The CRF function is modeled by Principal Component Analysis (PCA) of the Database of Response Functions (DoRF) compiled by Grossberg and Nayar, and the prior probability distribution is modeled by a Gaussian Mixture Model (GMM) of the PCA coefficients for the responses in the DoRF. CRF estimation results are presented for an ARRI electronic motion picture camera, showing the improved estimation accuracy and practicality of this method over previous methods for motion picture post-production workflows

Fricke and polymer gel 2D dosimetry validation using Monte Carlo simulation

Complexity in modern radiotherapy treatments demands advanced dosimetry systems for quality control. These systems must have several characteristics, such as high spatial resolution, tissue equivalence, three-dimensional resolution, and dose-integrating capabilities. In this scenario, gel dosimetry has proved to be a very promising option for quality assurance. In this study, the feasibility of Fricke and polymer gel dosimeters suitably shaped in form of thin layers and optically analyzed by visible light transmission imaging has been investigated for quality assurance in external radiotherapy. Dosimeter irradiation was carried out with a 6-MV photon beam (CLINAC 600C). The analysis of the irradiated dosimeters was done using two-dimensional optical transmission images. These dosimeters were compared with a treatment plan system using Monte Carlo simulations as a reference by means of a gamma test with parameters of 1 mm and 2%. Results show very good agreement between the different dosimetric systems: in the worst-case scenario, 98% of the analyzed points meet the test quality requirements. Therefore, gel dosimetry may be considered as a potential tool for the validation of other dosimetric systems.Fil: Vedelago, José Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Chacón Obando, D.. Universidad Nacional. Physics Department; Costa Rica. Universidad Nacional de Córdoba; ArgentinaFil: Malano, Francisco Mauricio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Conejeros, R.. Servicio de Radioterapia, Icos. Temuco, Chile;Fil: Figueroa, R.. Universidad de la Frontera; ChileFil: Garcia, D.. Servicio de Imagenes por Resonancia Magnética; ChileFil: González, G.. Servicio de Imagenes por Resonancia Magnética; ChileFil: Romero, Marcelo Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Santibañez, M.. Servicio de Imagenes por Resonancia Magnética; ChileFil: Strumia, Miriam Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Velásquez, J.. Servicio de Radioterapia; ChileFil: Mattea, Facundo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Valente, M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad de La Frontera. Departamento de Ciencias Físicas; Chil

Synthesis, Characterization and Evaluation of the Cytotoxicity of Ni-Doped Zn(Se,S) Quantum Dots

Quantum dots (QDs) are semiconductor nanocrystals with desirable optical properties for biological applications, such as bioimaging and drug delivery. However, the potential toxicity of these nanostructures in biological systems limits their application. The present work is focused on the synthesis, characterization, and evaluation of the toxicity of water-stable Ni-doped Zn(Se,S) QDs. Also, the study of nondoped nanostructures was included for comparison purposes. Ni-doped nanostructures were produced from zinc chloride and selenide aqueous solutions in presence of 3-mercaptopropionic acid and Ni molar concentration of 0.001 M. In order to evaluate the potential cytoxicity of these doped nanostructures, human pancreatic carcinoma cells (PANC-1) were used as model. The cell viability was monitored in presence of Ni-doped Zn(Se,S) QDs at concentrations ranging from 0 μg/mL to 500 μg/mL and light excited Ni-doped Zn(Se,S) nanostructures were evaluated at 50 μg/mL. Results suggested that Ni-doped Zn(Se,S) nanostructures were completely safe to PANC-1 when concentrations from 0 μg/mL to 500 μg/mL were used, whereas non-doped nanostructures evidenced toxicity at concentrations higher than 200 μg/mL. Also, Ni-doped Zn(Se,S) QDs under light excitation do not evidence toxicity to PANC-1. These findings suggest strongly that Zn(Se,S) nanostructures doped with nickel could be used in a safe manner in light-driving biological applications and drug delivery

Mutations in the anti-sigma H factor RshA confer resistance to econazole and clotrimazole in Mycobacterium smegmatis

Azole drugs such as econazole, are active on Mycobacterium tuberculosis and Mycobacterium smegmatis; however, the identification of their target(s) is still pending. It has been reported that mutations in the non-essential system mmpL5-mmpS5 conferred resistance to econazole in M. tuberculosis. We herein report that an azole-resistant mutant screen in M. smegmatis rendered mutations in rshA, encoding a non-essential anti-sigma H protein.Fil: Morbidoni, Héctor Ricardo. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Microbiología Molecular; ArgentinaFil: de la Iglesia, Agustina Inés. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Microbiología Molecular; ArgentinaFil: Figueroa, Virginia. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Microbiología Molecular; ArgentinaFil: Di Capua, Cecilia Beatriz. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Microbiología Molecular; ArgentinaFil: Ioerger, Thomas R.. Texas A&M University; Estados UnidosFil: Parish, Tanya. Infectious Disease Research Institute. TB Discovery Research; Estados Unido

Supersymmetry of gravitational ground states

A class of black objects which are solutions of pure gravity with negative cosmological constant are classified through the mapping between the Killing spinors of the ground state and those of the transverse section. It is shown that these geometries must have transverse sections of constant curvature for spacetime dimensions d below seven. For d > 6, the transverse sections can also be Euclidean Einstein manifolds. In even dimensions, spacetimes with transverse section of nonconstant curvature exist only in d = 8 and 10. This classification goes beyond standard supergravity and the eleven dimensional case is analyzed. It is shown that if the transverse section has negative scalar curvature, only extended objects can have a supersymmetric ground state. In that case, some solutions are explicitly found whose ground state resembles a wormhole.Comment: 16 pages, CECS style, minor correction

FRECUENCIA EN EL USO DE MEDICAMENTOS POR LAS GESTANTES QUE ACUDEN AL C.S. CIUDAD NUEVA EN EL AÑO 2000

El presente trabajo de Investigación determina la Frecuencia en el Uso de Medicamentos bajo Prescripción por Gestantes que acudieron al Centro de Salud de Ciudad Nueva durante el año 2000. Es una Investigación Descriptiva con un Diseño No experimental Transversal, y se realizó en una población de 475 gestantes, de las cuales se tomó como muestra representativa 190 pacientes, que represente el 40% del universo.   El tratamiento con medicamentos en gestantes presenta características particulares, ya que son dos organismos a los que puede afectar la acción de los medicamentos con distinta sensibilidad.   La administración de medicamentos supone un riesgo para la embarazada y el embrión o el feto. Sin embargo, otro principio importante es que no debe omitirse un tratamiento farmacológico indicado desde el punto de vista médico a la gestante.   El paso de medicamentos desde la madre al embrión o al feto a través de la placenta, podría originar en ciertos casos una afección teratogénica para este último. Es muy importante tener en cuenta el paso de éstos a través de la placenta para evitar su llegada o el uso innecesario, capaces de producir efectos adversos.   En nuestro estudio se encontró que el 57.90% de gestantes tomaron por lo menos un medicamento, valor mayor al encontrado por Whittle en Estados Unidos el año 85 y por Rubin en 1986, menor a los valores encontrados por la International Journal Of Gynecology Obstetrics los 80 y por De Jong Van den Berg, los años 1987-88 ere Holanda.   Se encontró que el 31.58% de gestantes que toman medicamentos son convivientes, el 52.62% del total de gestantes, que acuden al C.S. son convivientes.   Los medicamentos prescritos más tomados por las gestantes son el sulfato ferroso y Amoxicilina en tabletas, con 22.22% y 21.11% respectivamente

Aves asociadas al Aeropuerto Carriel Sur de Talcahuano, sur de Chile: evaluación de peligro aviario

Between the summer 2002 and 2005 was evaluated the richness and abundance of birds associated to the Carriel Sur Airport of Talcahuano and was estimated the collision risk representing each species for air navigation. Birds were counted in 10 count points distributed in different habitats around the landing runways. The collision risk was estimated by the Avian Hazard Index (AHI) which combines size, abundance and history of collisions of each species. During the study period 63 species were recorded, plus 10 aditional species were recorded after summer 2005. The most abundant species were the Grassland Yellow-Finch, Kelp Gull, Southern Lapwing Long-tailed Meadowlark (28%, 14%, 10%, 8% of all individual records). Excepting Kelp Gull, all remaining species exhibited seasonal cycles of abundance. The Kelp Gull showed multiyear outbreaks triggered. The species representing a higher collision risk for air navigation are the Kelp Gull (API = 36), Southern Lapwing (AHI = 24), South American Tern (AHI = 16), Black Vulture (AHI = 12), Neotropic Cormorant (AHI = 9) and Chimango Caracara (AHI = 8). However, the each species’ AHI varied temporally from very high to very low values according to changes in abundance. This study reflects the need for long-term assessments of changes in population size of bird species to better approximate the risk of bird-aircraft collisions.Entre el verano de 2002 y 2005 se evaluó la riqueza y abundancia de aves asociadas al Aeropuerto Carriel Sur de Talcahuano y se estimó el riesgo de colisión que representaría cada especie para la aeronavegación. Las aves fueron contabilizadas en 10 puntos de conteos distribuidos en distintos hábitats alrededor del las pistas de aterrizaje. El riesgo de colisión fue estimado mediante el índice de peligro aviario (IPA) el cual combina tamaño, abundancia e historial de colisiones de cada especie. Durante el periodo de estudio se registraron 63 especies, mas 10 especies que fueron registradas después del verano de 2005. Las especies más abundantes fueron el chirigüe, la gaviota dominicana, el queltehue y la loica (28%, 14%, 10%, 8% del total de registros individuales). Con excepción de la gaviota dominicana, todas las especies exhibieron ciclos estacionales de abundancia. La gaviota dominicana mostró irrupciones multianuales aparentemente por factores ambientales no bien determinados. Las especies que representarían un mayor riesgo de colisión para la aeronavegación son la gaviota dominicana (IPA = 36), el queltehue (IPA = 24), el gaviotín sudamericano (IPA = 16), el jote de cabeza negra (IPA = 12), el yeco (IPA = 9) y el tiuque (IPA = 8). Sin embargo, el IPA de cada especie varió temporalmente desde valores muy altos a valores muy bajos según los cambios de abundancia. Este estudio refleja la necesidad de evaluaciones de largo plazo de los cambios en el tamaño poblacional de especies de aves para una mejor aproximación del riesgo de colisiones aves-aeronaves

Mid-Infrared Laser Spectroscopy Applications I: Detection of Traces of High Explosives on Reflective and Matte Substrates

Mid-infrared (MIR) lasers have revolutionized infrared vibrational spectroscopy, converting an already dominant spectroscopic analysis technique into an even more powerful, easier to use, and quicker turn-around cadre of versatile spectroscopic tools. A selection of applications, revisited under the umbrella of MIR laser-based properties, very high brightness, collimated beams, polarized sources, highly monochromatic tunable sources, and coherent sources, is included. Applications discussed concern enhanced detection, discrimination, and quantification of high explosives (HEs). From reflectance measurements of chemical residues on highly reflective metallic substrates to reflectance measurements of HEs deposited on non-reflective, matte substrates is discussed. Coupling with multivariate analyses (MVA) techniques of Chemometrics allowed near trace detection of HEs, with sharp discrimination from highly MIR absorbing substrates

Endocardial Approach for Substrate Ablation in Brugada Syndrome

Radiofrequency ablation (RFA) in Brugada syndrome (BrS) has been performed by both endocardial and epicardial. The substrate in BrS is not completely understood. We investigate the functional endocardial substrate and its correlation with clinical, electrophysiological and ECG findings in order to guide an endocardial ablation. Two patients agreed to undergo an endocardial biopsy and the samples were examined with transmission electron microscopy (TEM) to investigate the correlation between functional and ultrastructural alterations. About 13 patients (38.7 ± 12.3 years old) with spontaneous type 1 ECG BrS pattern, inducible VF with programmed ventricular stimulation (PVS) and syncope without prodromes were enrolled. Before endocardial mapping, the patients underwent flecainide testing with the purpose of measuring the greatest ST-segment elevation for to be correlated with the size and location of substrate in the electro-anatomic map. Patients underwent endocardial bipolar and electro-anatomic mapping with the purpose of identify areas of abnormal electrograms (EGMs) as target for RFA and determine the location and size of the substrate. When the greatest ST-segment elevation was in the third intercostal space (ICS), the substrate was located upper in the longitudinal plane of the right ventricular outflow tract (RVOT) and a greatest ST-segment elevation in fourth ICS correspond with a location of substrate in lower region of longitudinal plane of RVOT. A QRS complex widening on its initial and final part, with prolonged transmural and regional depolarization time of RVOT corresponded to the substrate located in the anterior-lateral region of RVOT. A QRS complex widening rightwards and only prolonged transmural depolarization time corresponded with a substrate located in the anterior, anterior-septal or septal region of RVOT. RFA of endocardial substrate suppressed the inducibility and ECG BrS pattern during 34.7 ± 15.5 months. After RFA, flecainide testing confirmed elimination of the ECG BrS pattern. Endocardial biopsy showed a correlation between functional and ultrastructural alterations. Endocardial RFA can eliminate the BrS phenotype and inducibility during programmed ventricular stimulation (PVS)