Trypanosomatids are an important group of parasites that predominate in tropical and subtropical areas of the planet, which cause diseases that are classified as forgotten and neglected by the world ...health organization. In this group of parasites, we find Trypanosoma cruzi, Trypanosoma brucei, Trypanosoma brucei rhodesiense and Leishmania spp, for which there is no vaccine available, and its control has focused mainly on pharmacological treatment. Due to the poverty situation where these diseases are found and the biological complexity of these parasites, there are multiple variables to control, including the diversity of species, the complexity of their life cycles, drug resistance, cytotoxicity, the limited use in pregnant women, the high costs of treatment and the little-known pharmacological mechanisms of action, among others. It is therefore necessary to find new strategies and approaches for the treatment of these parasitic diseases. Among these new approaches is the rational search for new targets based on the allosteric inhibition of protein kinases, which have been little studied in trypanosomatids. Among these kinases, we find Glycogen Synthase Kinase-3 (GSK-3), a kinase of great pharmacological interest, which is under intense basic and clinical research by pharmaceutical companies for the treatment of cancer. This kinase, highly studied in the PI3K/AKT/mTOR pathway signaling in humans, has an orthologous gene in these parasites (GSK-3 s), which has proven to be essential for them in response to different challenges; Therefore, it is notable to increase research in this kinase in order to achieve a broad structural and functional characterization in the different species of trypanosomatids.
Mutual Information (MI) is a useful Information Theory tool for the recognition of mutual dependence between data sets. Several methods have been developed fore estimation of MI when both data sets ...are of the discrete type or when both are of the continuous type. However, MI estimation between a discrete range data set and a continuous range data set has not received so much attention. We therefore present here a method for the estimation of MI for this case, based on the kernel density approximation. This calculation may be of interest in diverse contexts. Since MI is closely related to the Jensen Shannon divergence, the method developed here is of particular interest in the problems of sequence segmentation and set comparisons.
Promastigotes of
Leishmania (
Viannia)
panamensis were successfully transfected with p6.5-
egfp to express green fluorescent protein. The transfectants remained infective to macrophages, providing an
...in vitro model for screening antileishmanial drugs. This was demonstrated by flow cytometry of macrophage-associated GFP after exposure of infected cultures to known antileishmanial drugs, i.e. amphotericin B and glucantime
®. Fluorescence of GFP diminished progressively from infected cells with increasing drug concentrations used in both cases. The availability of this fluorescent assay for infection of macrophages by
L. (
V.)
panamensis facilitates drug discovery program for the
Viannia species, which differ significantly from those of the
Leishmania subgenus.
The purpose of this work is to use the divergence of Jensen-Shannon to compare spectra of cloud droplet sizes corresponding to different experimental conditions. Results of laboratory measurements ...are analyzed in which the diameter of droplets, produced by means of an ultrasonic nebulizer, are determined, subject to different movement conditions within a "cloudbox". The turbulence energy dissipation rate is particularly considered. The droplet spectra were approximated by the density kernel method.
In images obtained with coherent lighting such as synthetic aperture radar (SAR), a multiplicative noise known as speckle appears. The speckle makes radiometric homogeneous zones respond with Gamma ...type distributions. The detection of edges in this type of images is of interest and usefulness in many applications. In this paper three methods of analysis by segmentation based on the calculation of the Jensen Shannon Divergence that can be applied to SAR images are proposed. The approximation of the probability distributions was carried out using the density Kernel method.
En imágenes obtenidas con iluminación coherente como las de radar de apertura sintética (SAR), aparece un ruido multiplicativo conocido como speckle. El speckle hace que zonas radiométricamente ...homogéneas respondan con distribuciones tipo Gamma. La detección de bordes en este tipo de imágenes es de interés y utilidad en muchas aplicaciones. En este trabajo se proponen tres métodos de análisis mediante segmentación basados en el cálculo de la Divergencia de Jensen Shannon que pueden ser aplicados a imágenes SAR. La aproximación de las distribuciones de probabilidad se realizó mediante el método del Kernel de densidad.
El propósito de este trabajo es emplear la divergencia de Jensen-Shannon para comparar espectros de tamaños de gotas de nubes correspondientes a diferentes condiciones experimentales. Se analizan ...resultados de mediciones de laboratorio en los que se determinó el diámetro de gotas, producidas mediante un nebulizador ultrasónico, sometidas a diferentes condiciones de movimiento dentro de una "caja de nube". Se considera en particular la tasa de disipación de energía por turbulencia. A los espectros de gotas se los aproximó mediante el método del kernel de densidad.
Se presenta un método para la detección de bordes de dominio o cambios de estacionariedad en secuencias de valores de rango continuo como los obtenidos en Electromiografía (EMG) o en registros de ...Electroencefalograma (EEG). La detección del cambio de estacionariedad en una secuencia temporal como las mencionadas presenta interés para el reconocimiento del comienzo de una contracción muscular en EMG o del comienzo y propagación de una crisis epiléptica en el análisis del registro del EEG. El punto de segmentación en una serie temporal se corresponde con la posición en la serie a partir de la cual cambian las propiedades estadísticas de los valores que la conforman. El método aquí propuesto se basa en el cálculo de la divergencia de Jensen-Shannon (DJS) entre los segmentos que forman la secuencia. La DJS es una medida de distancia entre distribuciones de probabilidad y para su evaluación aproximamos las distribuciones que corresponden a cada segmento por el método del kernel de densidad. Para la aplicación del método se elige una posición en la secuencia como punto de segmentación y se calcula la DJS entre las distribuciones asociadas a las sub-secuencias que quedan así definidas. Se repite este proceso para cada posición en la secuencia y se identifica el punto de segmentación con la posición que arroja el valor máximo para la DJS. Evaluamos método propuesto analizando señales sintéticas similares a señales electromiográficas.
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•Combining Selective Laser Melting (SLM) and Laser Shock Peening (LSP) offers a new route to control microstructure and mechanical properties in 3D.•LSP significantly increases the ...microhardness of SLM As-Built parts in the near surface region but does not change grain size.•The LSP affected zone recrystallizes much faster upon heat treatment than the As-Built SLM, resulting in a refined, equiaxed grain structure.
Metallic parts made by Selective Laser Melting (SLM) are known for their heterogeneous microstructures in the as-built (AB) state. In this paper, Laser Shock Peening (LSP) was performed on a 316 L stainless steel part fabricated by SLM. The LSP treatment increases the stored energy in the material but does not lead to measurable grain refinement. When subsequently annealed, the LSP treated sample undergoes recrystallization and transforms into a refined equiaxed structure, while this transformation is not activated yet for the AB sample. The LSP strategy therefore offers new routes for the selective 3D control of microstructures and mechanical properties of SLM parts.
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