Determinación de selénio por su efecto catalítico en la reducción del azul de toluidina por el ion sulfuro

The reduction of toluidine blue by sulphide is catalysed by small amounts of selenium. As a consequence a new kinetic method for the selenium determination is developed. The experimental conditions have been optimized and the variable time method appears to be the most suitable for the determination of selenium. The new method is very sensitive (10 ng/ml) showing good accuracy. Most of the interferences from diverse metallic ions are eliminated by the addition of an excess of Ba(II)-EDTA.La reducción del azul de toluidina por el sidfuro es catalizada cuando se encuentran presentes pequeñas cantidades de selenio. Como consecuencia de esto aportamos un nuevo método cinético para la determinación de selenio. Las condiciones experimentales han sido optimizadas y el método cinético de tiempo variable se seleccionó como más conveniente para las determinaciones analíticas de selenio. El nuevo procedimiento es muy sensible (10 ng/ml) y presenta buena exactitud y precisión. La mayoría de las interferencias producidas por 'los iones metálicos se eliminan mediante la adición de un exceso de AEDT-Ba2

Oxidaciones de leucocolorantes derivados del trifenil metano con cloramina T, catalizadas por el ioduro. Determinaciones de ioduro, plata, mercurio y paladio

The oxidation of leuco crystal violet and of leuco malachite green by chloramine T is catalysed by iodide. Two sensitive, accurate, selective and rapid methods for the determination of iodide are proposed. Ag(I), Hg(II) and Pd(II) ions under suitable conditions inhibit the catalytic effect of iodide on oxidation of reduced form of both dyes by chloramine T. The kinetic determination of these metallic ions is useful at the trace range.La oxidación del leucovioleta cristal y leucoverde malaquita por la cloramina T es catalizada por el ioduro. Basados en este efecto se proponen dos métodos para la determinación de ioduro sensibles, exactos, selectivos y rápidos. En condiciones adecuadas los iones Ag(I), Hg(II) y Pd(II) inhiben la acción catalítica del ioduro sobre la oxidación de las formas reducidas de ambos colorantes por la cloramina T. Las determinaciones cinéticas de estos iones metálicos son aplicables en rangos de concentración a niveles de trazas

Learning the progression patterns of treatments using a probabilistic generative model

Modeling a disease or the treatment of a patient has drawn much attention in recent years due to the vast amount of information that Electronic Health Records contain. This paper presents a probabilistic generative model of treatments that are described in terms of sequences of medical activities of variable length. The main objective is to identify distinct subtypes of treatments for a given disease, and discover their development and progression. To this end, the model considers that a sequence of actions has an associated hierarchical structure of latent variables that both classifies the sequences based on their evolution over time, and segments the sequences into different progression stages. The learning procedure of the model is performed with the Expectation–Maximization algorithm which considers the exponential number of configurations of the latent variables and is efficiently solved with a method based on dynamic programming. The evaluation of the model is twofold: first, we use synthetic data to demonstrate that the learning procedure allows the generative model underlying the data to be recovered; we then further assess the potential of our model to provide treatment classification and staging information in real-world data. Our model can be seen as a tool for classification, simulation, data augmentation and missing data imputation.EJ-GV PREDOC 201

Identifying common treatments from Electronic Health Records with missing information. An application to breast cancer.

The aim of this paper is to analyze the sequence of actions in the health system associated with a particular disease. In order to do that, using Electronic Health Records, we define a general methodology that allows us to: (I) identify the actions in the health system associated with a disease; (ii) identify those patients with a complete treatment for the disease; (iii) and discover common treatment pathways followed by the patients with a specific diagnosis. The methodology takes into account the characteristics of the EHRs, such as record heterogeneity and missing information. As an example, we use the proposed methodology to analyze breast cancer disease. For this diagnosis, 5 groups of treatments, which fit in with medical practice guidelines and expert knowledge, were obtained.Artificial Intelligence in BCAM number EXP. 2019/00432, PID2019-104966GB-I00, TIN2016-78365-R, IT1244-19

Applying MAPP Algorithm for Cooperative Path Finding in Urban Environments

The paper considers the problem of planning a set of non-conflict trajectories for the coalition of intelligent agents (mobile robots). Two divergent approaches, e.g. centralized and decentralized, are surveyed and analyzed. Decentralized planner - MAPP is described and applied to the task of finding trajectories for dozens UAVs performing nap-of-the-earth flight in urban environments. Results of the experimental studies provide an opportunity to claim that MAPP is a highly efficient planner for solving considered types of tasks

Aplicaciones analíticas de la reducción fotoquímica de la riboflavina el ácido etilenodiaminotetraacético. Determinación de ioduro

A kinetic study of the photochemical reaction of riboflavin and EDTA (in the absence of oxygen) has been made in connection with development of a new kinetic method for iodide. The reaction is first-order with respect to riboflavin, EDTA and absorbed light-intensity. The rate of photoreduction is strongly pH^dependent, and maximal at about pH 7,5. The photoreduction involves a long-Uved excited state of the vitamin B2 and is dramaticalUy retarded by small amounts of iodide. A tenta'tive mechanism is proposed, and the experimental conditions have been optimized. The variable time method appears to be the most suitable for determination of iodide. A detection limit of 8 [xg/rnl and a casfficient of variation about 3 % can be adhieved. Chloride and bromide do not interfere at levéis below 100-fold mole ratio to iodide. Metal ions do not interfere if enough excess of EDTA is used.Se ha estudiado la reacción fotoquímica entre la riboflavina y el ácido etilenodiaminotetraacético (en ausencia de oxígeno) con la finalidad de desarrollar un método cinético para la determinación de ioduro. La reacción es de primer orden con respecto a la riboflavina, AEDT e intensidad de la radiación absorbida. La velocidad del proceso fotoquímico depende del pH y es máxima a pH 7,2. La fotorreducción tiene lugar a través de estados excitados de larga vida de la vitamina B2 y está muy afectada por la presencia de pequeñas cantidades de ioduro. Se propone un posible mecanismo y se han estudiado todas las variables con la finalidad de optimizar las condiciones del método analítico. Se ha empleado el procedimiento del tiempo variable como el más apropiado para la determinación de ioduro. La sensibilidad es de 8 fig/ml y el coeficien'te de variación del 3 %. Los iones bromuro y cloruro son compatibles hasta la relación 100/1. La interferencia de los iones metálicos se elimina añadiendo un exceso de AEDT

Heavy quark flavour dependence of multiparticle production in QCD jets

After inserting the heavy quark mass dependence into QCD partonic evolution equations, we determine the mean charged hadron multiplicity and second multiplicity correlators of jets produced in high energy collisions. We thereby extend the so-called dead cone effect to the phenomenology of multiparticle production in QCD jets and find that the average multiplicity of heavy-quark initiated jets decreases significantly as compared to the massless case, even taking into account the weak decay products of the leading primary quark. We emphasize the relevance of our study as a complementary check of $b$-tagging techniques at hadron colliders like the Tevatron and the LHC.Comment: Version revised, accepted for publication in JHEP, 21 pages and 7 figure

Robots That Do Not Avoid Obstacles

The motion planning problem is a fundamental problem in robotics, so that every autonomous robot should be able to deal with it. A number of solutions have been proposed and a probabilistic one seems to be quite reasonable. However, here we propose a more adoptive solution that uses fuzzy set theory and we expose this solution next to a sort survey on the recent theory of soft robots, for a future qualitative comparison between the two.Comment: To appear in the Handbook of Nonlinear Analysis, Edt Th. Rassias, Springe