The dog or its muzzle as a signal of danger to humans?

In France, dogs of specific breeds as well as dogs trained to attack (police, security services, etc.) have to be muzzled in public areas. A dog wearing a muzzle may constitute an ambiguous cue for humans as it indicates that the dog is potentially dangerous while at the same time that the dog’s potential danger is controlled. The aim of our present study was to determine whether a muzzled dog would induce a greater fear response in humans than the same non-muzzled dog. We were interested specifically in the German shepherd dog as it is one of the typical breeds used by police and security services, but also very popular as a pet

Whole-Cell Analysis of Low-Density Lipoprotein Uptake by Macrophages Using STEM Tomography

Nanoparticles of heavy materials such as gold can be used as markers in quantitative electron microscopic studies of protein distributions in cells with nanometer spatial resolution. Studying nanoparticles within the context of cells is also relevant for nanotoxicological research. Here, we report a method to quantify the locations and the number of nanoparticles, and of clusters of nanoparticles inside whole eukaryotic cells in three dimensions using scanning transmission electron microscopy (STEM) tomography. Whole-mount fixed cellular samples were prepared, avoiding sectioning or slicing. The level of membrane staining was kept much lower than is common practice in transmission electron microscopy (TEM), such that the nanoparticles could be detected throughout the entire cellular thickness. Tilt-series were recorded with a limited tilt-range of 80° thereby preventing excessive beam broadening occurring at higher tilt angles. The 3D locations of the nanoparticles were nevertheless determined with high precision using computation. The obtained information differed from that obtained with conventional TEM tomography data since the nanoparticles were highlighted while only faint contrast was obtained on the cellular material. Similar as in fluorescence microscopy, a particular set of labels can be studied. This method was applied to study the fate of sequentially up-taken low-density lipoprotein (LDL) conjugated to gold nanoparticles in macrophages. Analysis of a 3D reconstruction revealed that newly up-taken LDL-gold was delivered to lysosomes containing previously up-taken LDL-gold thereby forming onion-like clusters

Whole-cell analysis of low-density lipoprotein uptake by macrophages using STEM tomography

Nanoparticles of heavy materials such as gold can be used as markers in quantitative electron microscopic studies of protein distributions in cells with nanometer spatial resolution. Studying nanoparticles within the context of cells is also relevant for nanotoxicological research. Here, we report a method to quantify the locations and the number of nanoparticles, and of clusters of nanoparticles inside whole eukaryotic cells in three dimensions using scanning transmission electron microscopy (STEM) tomography. Whole-mount fixed cellular samples were prepared, avoiding sectioning or slicing. The level of membrane staining was kept much lower than is common practice in transmission electron microscopy (TEM), such that the nanoparticles could be detected throughout the entire cellular thickness. Tilt-series were recorded with a limited tilt-range of 80u thereby preventing excessive beam broadening occurring at higher tilt angles. The 3D locations of the nanoparticles were nevertheless determined with high precision using computation. The obtained information differed from that obtained with conventional TEM tomography data since the nanoparticles were highlighted while only faint contrast was obtained on the cellular material. Similar as in fluorescence microscopy, a particular set of labels can be studied. This method was applied to study the fate of sequentially up-taken low-density lipoprotein (LDL) conjugated to gold nanoparticles in macrophages. Analysis of a 3D reconstruction revealed that newly up-taken LDL-gold was delivered to lysosomes containing previously up-taken LDL-gold thereby forming onion-like clusters

Thresholds Optimization of Decomposed Vector Rotation Model for Digital Predistortion of RF Power Amplifier

In this paper, we propose an efficient approach for optimizing the decomposed vector rotation (DVR) model for digital predistortion (DPD). The DVR model’s basis functions are constructed piecewise by dividing the input space into segments bounded by thresholds. This paper investigates how to set the thresholds optimally using an iterative approach based on the decomposition of the global optimization problem into a set of unimodal sub-problems so that a unidirectional minimization can be used to optimize the positions of thresholds. The proposed approach has been evaluated using measurements from a real power amplifier (PA). The experimental results illustrate the efficiency of the proposed optimization approach and show that the thresholds’ optimization improves linearization performances significantly compared to conventional DVR with uniform segmentation

Análisis de linajes maternos y paternos de bovinos criollo del Centro de Ecología Aaplicada Simón I. Patiño - Bolivia

Se determinaron los linajes maternos y paternos de 33 bovinos Criollo (27 hembras y 6 machos) del Centro de Ecología Aplicada Simón I. Patiño (Ceasip) mediante marcadores genéticos del ADN genómico, mitocondrial y del cromosoma Y. El ADN genómico se extrajo utilizando el kit Wizard ® Genomic Purification. Los linajes maternos se determinaron mediante secuenciación del ADN mitocondrial (región control D-loop) y los linajes paternos se determinaron analizando siete marcadores genéticos del cromosoma Y, dos SNP (Polimorfismo de Nucleótido Simple) y cinco microsatélites (Secuencias Repetidas en Tándem). La diversidad genética se estimó tipificando 18 microsatélites. Se analizaron los datos con MStools, GenePop y Arlequin. La secuenciación de D-loop mitocondrial permitió detectar seis linajes maternos, que incluían cuatro haplotipos mitocondriales de origen europeo y dos africanos. A través del análisis de los marcadores del cromosoma Y se determinaron tres linajes paternos, dos taurinos y uno cebuino. En el hato del Ceasip, la diversidad alélica (na) fue de 6.11, mientras que la heterocigosidad esperada (He) fue de 0.70 y la observada (Ho) fue de 0.68. Los valores de diversidad genética observada en los bovinos del Ceasip son similares a los estimados para la mayoría de los biotipos del Criollo boliviano (na Yacumeño= 6.82; na Saavedreño= 5.95), siendo los valores promedios para el ganado Criollo boliviano analizados anteriormente de na= 6.39, He= 0.72 y Ho= 0.65. Los análisis de Componentes Principales y de distancia genética mostraron que sería factible intercambiar material genético entre las poblaciones Criollo bolivianas sin pérdida significativa de su diversidad genética.Fil: Pereira, J. A. C.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Peña, S.. Centro de Ecología Aplicada Simón I. Patiño; BoliviaFil: Liron, Juan Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria ; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Loza, A. J.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Posik, Diego Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria ; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Baudoin, M.. Centro de Ecología Aplicada Simón I. Patiño; BoliviaFil: Bomblat, C.. Centro de Ecología Aplicada Simón I. Patiño; Bolivi

Curvature-dimension inequalities and Li-Yau inequalities in sub-Riemannian spaces

In this paper we present a survey of the joint program with Fabrice Baudoin originated with the paper \cite{BG1}, and continued with the works \cite{BG2}, \cite{BBG}, \cite{BG3} and \cite{BBGM}, joint with Baudoin, Michel Bonnefont and Isidro Munive.Comment: arXiv admin note: substantial text overlap with arXiv:1101.359

Analisis de la variabilidad molecular de una coleccion peruana de Smallanthus sonchofolius (Poepp & Endl) H. Robinson

peer reviewe

Explicit formulae in probability and in statistical physics

We consider two aspects of Marc Yor's work that have had an impact in statistical physics: firstly, his results on the windings of planar Brownian motion and their implications for the study of polymers; secondly, his theory of exponential functionals of Levy processes and its connections with disordered systems. Particular emphasis is placed on techniques leading to explicit calculations.Comment: 14 pages, 2 figures. To appear in Seminaire de Probabilites, Special Issue Marc Yo