1,289 research outputs found
Ultrarobust calibration of an optical lattice depth based on a phase shift
We report on a new method to calibrate the depth of an optical lattice. It
consists in triggering the intrasite dipole mode of the cloud by a sudden phase
shift. The corresponding oscillatory motion is directly related to the
intraband frequencies on a large range of lattice depths. Remarkably, for a
moderate displacement, a single frequency dominates this oscillation for the
zeroth and first order interference pattern observed after a sufficiently long
time-of-flight. The method is robust against atom-atom interactions and the
exact value of the extra external confinement of the initial trapping
potential.Comment: 7 pages, 6 figure
Cuerpos extraños endobronquiales en adultos: a propósito de dos casos Airways foreign bodies in adults: a purpose of two cases
La aspiración de un cuerpo extraño (CE) en la vía aérea es un evento que puede ser potencialmente mortal. La broncos- copia flexible y la broncoscopia rígida han sido la base tanto del diagnóstico como del tratamiento en los pacientes con sospecha de aspiración de un CE. Aunque la extracción de un CE fue tradicionalmente manejada por otorrinolaringólo- gos y cirujanos torácicos, la evolución de los broncoscopios flexibles ha ampliado el papel de los neumólogos en el diagnóstico y tratamiento de estos pacientes. Exponemos dos casos de aspiración de un CE extraídos por neumólogos mediante broncoscopia flexible
Pulmón del soldador asociado a sobrecarga sistémica de hierro: a propósito de una caso
La hemosiderosis pulmonar o pulmón del soldador es una enfermedad ocupacional, provocada por la exposición crónica al polvo de hierro, en la que se produce un depósito anormal de este material en el pulmón en forma de hemosiderina
Computer Vision and Metrics Learning for Hypothesis Testing: An Application of Q-Q Plot for Normality Test
This paper proposes a new procedure to construct test statistics for
hypothesis testing by computer vision and metrics learning. The application
highlighted in this paper is applying computer vision on Q-Q plot to construct
a new test statistic for normality test. Traditionally, there are two families
of approaches for verifying the probability distribution of a random variable.
Researchers either subjectively assess the Q-Q plot or objectively use a
mathematical formula, such as Kolmogorov-Smirnov test, to formally conduct a
normality test. Graphical assessment by human beings is not rigorous whereas
normality test statistics may not be accurate enough when the uniformly most
powerful test does not exist. It may take tens of years for statistician to
develop a new and more powerful test statistic. The first step of the proposed
method is to apply computer vision techniques, such as pre-trained ResNet, to
convert a Q-Q plot into a numerical vector. Next step is to apply metric
learning to find an appropriate distance function between a Q-Q plot and the
centroid of all Q-Q plots under the null hypothesis, which assumes the target
variable is normally distributed. This distance metric is the new test
statistic for normality test. Our experimentation results show that the
machine-learning-based test statistics can outperform traditional normality
tests in all cases, particularly when the sample size is small. This study
provides convincing evidence that the proposed method could objectively create
a powerful test statistic based on Q-Q plots and this method could be modified
to construct many more powerful test statistics for other applications in the
future
Estudio de medios de cultivo para la conservación in vitro de la yuca
Plant tissue culture constitutes an alternative for germplasm conservation in case of vegetatively propagated species. This approach permits to maintain collections in small places free from attach of diseases and catastrophes. Eleven variants from MS culture media were tested. Variants consist of different sucrose (20, 30 and 40 g.l-1) and manitol (0, 10, 20 y 30 g.l-1) concentrations in order to decrease the subculture number in the in vitro storage of ‘Señorita’ and ‘CEMSA 74-725’ clones. Evaluations were carried out nine months after in vitro implantation based on: height (cm), internode number by plant, number of active leave, number of active roots and surviving percentage. After storage, explants were incubated for recovery in the described culture medium for in vitro cassava growing. A culture medium with the addition of 40 g.l-1 sucrose, 0.02 mg.l-1 BAP, 0.1 mg.l-1 de GA3 and 0.01 mg.l-1 ANA is recommended.Key Words: Manihot esculenta, micropropagation, genetics resoursesEl cultivo de tejidos vegetales constituye una alternativa para la conservación del germoplasma de especies que son propagadas vegetativamente. Su utilización permite mantener las colecciones en pequeños espacios, libres del ataque de enfermedades y catástrofes, además de facilitar el intercambio de germoplasma. Se estudiaron 11 variantes del medio de cultivo MS que consistieron en diferentes concentraciones de sacarosa (20, 30 y 40 g.l-1) y de manitol (0, 10, 20 y 30 g.l-1), con el objetivo de disminuir el número de subcultivos en la conservación in vitro de los clones Señorita y CEMSA 74-725. Las evaluaciones se realizaron a los nueve meses de la implantación in vitro, teniendo en cuenta: altura (cm), número de entrenudos por planta, número de hojas activas, número de raíces activas y porcentaje de supervivencia. Los explantes que sobrevivieron, después de la conservación fueron incubados para su recuperación en el medio de cultivo descrito para el crecimiento in vitro de la yuca. El medio de cultivo suplementado con 40 g.l-1 de sacarosa, 0.02 mg.l-1 de BAP, 0.1 mg.l-1 de GA3 y 0.01 mg.l-1 de ANA, resultó la mejor variante para la conservación in vitro de ambos clones.Palabras clave: Manihot esculenta, micropropagación, recursos genético
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