Search results for "VECTOR"
showing 10 items of 2660 documents
Diversidad genética de los principales vectores de la enfermedad de Chagas en Brasil: repercusiones epidemiológicas en el control de la enfermedad
2017
La enfermedad de Chagas, también llamada Tripanosomiasis Americana, es una enfermedad potencialmente mortal causada por el parásito protozoo Trypanosoma cruzi, es endémica de América Latina y transmitida, principalmente, por vectores hemípteros de la subfamilia Triatominae adaptados a los hábitats doméstico y peridoméstico. Puesto que el parásito se mantiene en un ciclo zoonótico silvestre y es imposible de eliminar, la única forma de luchar contra la transmisión vectorial consiste en la eliminación de las poblaciones domiciliadas del vector. Los estudios moleculares constituyen una herramienta de gran utilidad a la hora de planificar las campañas de control vectorial, puesto que permiten c…
Epidemiología y Control de la Enfermedad de Chagas en el Departamento de Cochabamba (Bolivia).
2015
La enfermedad de Chagas es uno de los problemas más graves de salud pública que afectan a América Latina; históricamente extensas áreas de Bolivia han registrado la mayor prevalencia de la infección por su agente causal, el protozoo Trypanosoma cruzi. A principios del año 2000, en este país se puso en marcha un programa de control vectorial, que consistió en el rociado masivo de viviendas con insecticidas piretroides, instaurado para controlar la infestación de viviendas por los insectos hematófagos que transmiten la enfermedad. En este trabajo se proporciona una evaluación detallada de los efectos de este programa en el Departamento de Cochabamba, uno de los lugares más endémico de todo el…
Students' problems in the identification of subspaces in Linear Algebra
2018
International audience; The goal of the study presented in this paper is the investigation of students' problems with exercises concerning central topics of linear algebra courses at university level. We present the results of our analysis of students' work on an exercise about subspaces of . We evaluated the written solutions of the task as well as transcripts based on videos taken of student groups working on the problem. We identified and classified descriptions of vector spaces and subspaces that varied widely and demonstrated highly different skills in working with geometric or formal algebraic objects. We analyzed how far students could progress in a complex reasoning process, and ide…
Prompt Determination of the Mechanical Properties of Industrial Polypropylene Sandwich Pipes
2021
A simple and prompt method to determine the mechanical properties of industrial multilayer extrusion polypropylene pipes for a gravity sewer network is suggested. The engineering formulas included for calculating the permissible thickness and relative position of a foam core in the pipes are based on a linear-elastic approximation and the rule of mixtures. The applicability of the approximation was justified experimentally during investigation of the effective tensile characteristics of single- and multilayer pipes and each layer specimen by using traditional tests and finite-element calculations. The results obtained were used to formulate engineering recommendations for calculations of th…
Regulation of type 1 fimbriae synthesis and biofilm formation by the transcriptional regulator LrhA of Escherichia coli
2005
Type 1 fimbriae ofEscherichia colifacilitate attachment to the host mucosa and promote biofilm formation on abiotic surfaces. The transcriptional regulator LrhA, which is known as a repressor of flagellar, motility and chemotaxis genes, regulates biofilm formation and expression of type 1 fimbriae. Whole-genome expression profiling revealed that inactivation oflrhAresults in an increased expression of structural components of type 1 fimbriae.In vitro, LrhA bound to the promoter regions of the twofimrecombinases (FimB and FimE) that catalyse the inversion of thefimApromoter, and to the invertible element itself. TranslationallacZfusions with these genes and quantification offimEtranscript le…
La Géométrie pour l'Unicité, la Parcimonie et l'Appariement des Estimateurs Pénalisés
2022
During the talk we will give a necessary and sufficient condition for the uniqueness of a penalized least squares estimator whose penalty term is a polyhedral norm. Our results cover many methods including the OSCAR, SLOPE and LASSO estimators as well as the related method of basis pursuit. The geometrical condition for uniqueness involves how the row span of the design matrix intersects the faces of the dual normunit ball. Theoretical results on sparsity by LASSO and basis pursuit estimators are deduced from this condition via the characterization of accessible sign vectors for these two methods.
Assessing Transfer Entropy in cardiovascular and respiratory time series: A VARFI approach
2021
In the study of complex biomedical systems represented by multivariate stochastic processes, such as the cardiovascular and respiratory systems, an issue of great relevance is the description of the system dynamics spanning multiple temporal scales. Recently, the quantification of multiscale complexity based on linear parametric models, incorporating autoregressive coefficients and fractional integration, encompassing short term dynamics and long-range correlations, was extended to multivariate time series. Within this Vector AutoRegressive Fractionally Integrated (VARFI) framework formalized for Gaussian processes, in this work we propose to estimate the Transfer Entropy, or equivalently G…
Highly Sensitive Polarization Rotation Measurement through a High‐Order Vector Beam Generated by a Metasurface
2020
The precise determination of the polarization state of light is fundamental for a vast variety of applications in remote sensing, astronomy, optics and terahertz technology, to name just a few. Typically, polarization characterization is performed by using a combination of multiple optical devices such as beam splitters, polarizers, and waveplates. Moreover, to achieve high-precision, balanced photodetectors and lock-in amplifiers are employed, thus contributing to increasing system complexity. Here, a technique for polarization rotation measurements with a dynamic range of 180° and a sensitivity of about 10−2 degrees is realized using a properly designed metasurface. Such device generates …
"Table 22" of "Combination of the searches for pair-produced vector-like partners of the third-generation quarks at $\sqrt{s} =$ 13 TeV with the ATLA…
2018
Expected and observed 95% upper limits on the vector-like bottom quark pair-production signal strength (i.e. the ratio sigma_exclusion/sigma_VLQ) as a function of the branching ratio for a vector-like quark mass of 1400 GeV, asumming that the vector-like quarks exclusively decay to SM particles (and third generation quarks). If interpreting these results in models with decays to non-Standard-Model particles, one must check that the additional decays will not end up in any control regions of the relevant analyses.
"Table 20" of "Combination of the searches for pair-produced vector-like partners of the third-generation quarks at $\sqrt{s} =$ 13 TeV with the ATLA…
2018
Expected and observed 95% upper limits on the vector-like bottom quark pair-production signal strength (i.e. the ratio sigma_exclusion/sigma_VLQ) as a function of the branching ratio for a vector-like quark mass of 1200 GeV, asumming that the vector-like quarks exclusively decay to SM particles (and third generation quarks). If interpreting these results in models with decays to non-Standard-Model particles, one must check that the additional decays will not end up in any control regions of the relevant analyses.