Single- and few-layer graphene by ambient pressure chemical vapor deposition on nickel

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2010.Includes bibliographical references (p. 169-177).An ambient pressure chemical vapor deposition (APCVD) process is used to fabricate graphene based films consisting of one to several graphene layers across their area. Polycrystalline Ni thin films are used and the graphene can be transferred from the Ni surface to dielectric substrates in order to integrate them to graphene device prototypes. Uniform single layer graphene can be grown with the same process by using single crystalline Ni with a (111) surface orientation. Raman spectroscopy and electron diffraction characterization is undertaken in order to determine the nature of the layer stacking for the case of multilayer graphene.by Alfonso Reina Ceeco.Ph.D

Construction and Calibration of a Low-Cost 3D Laser Scanner with 360◦ Field of View for Mobile Robots

Navigation of many mobile robots relies on environmental information obtained from three-dimensional (3D) laser scanners. This paper presents a new 360◦ field-of-view 3D laser scanner for mobile robots that avoids the high cost of commercial devices. The 3D scanner is based on spinning a Hokuyo UTM- 30LX-EX two-dimensional (2D) rangefinder around its optical center. The proposed design profits from lessons learned with the development of a previous 3D scanner with pitching motion. Intrinsic calibration of the new device has been performed to obtain both temporal and geometric parameters. The paper also shows the integration of the 3D device in the outdoor mobile robot Andabata.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Prevalencia de marcadores infecciosos en donantes de sangre en el Hospital Militar Central del 2005 al 2010

El riesgo de transmisión de enfermedades infecciosas por transfusiones sanguíneas tales como el VIH (Virus de Inmunodeficiencia Humana), VHB (Virus de Hepatitis B), VHC (Virus de Hepatitis C), Sífilis, VLTH (Virus Linfotrófico Humano de Células T) han sido bien documentada por décadas, estas enfermedades afectan no solo al paciente sino también a su familia, la comunidad y la economía del país. Por ello se han venido generando políticas seguras para disminuir dicho riesgo de transmisión, realizándose la selección de donantes de bajo riesgo (Identificados como aquellos donantes voluntarios, no usuarios de drogas intravenosas, sin antecedentes previos de enfermedades de transmisión sexual y presencia de tatuajes entre otras), implementación de pruebas más sensibles y específicas para la determinación de dichas enfermedades, y la vigilancia pos transfusión. Todo lo anterior ha permitido un descenso significativo en la prevalencia de infecciones transmitidas por transfusiones sanguínea como se ha reportado durante los últimos años para VIH cuya prevalencia se redujo del 0.03% al 0.015% y para Hepatitis C del 0.63% al 0.4

Shifts in the Distribution of Mass Densities Is a Signature of Caloric Restriction in Caenorhabditis elegans

Although the starvation response of the model multicellular organism Caenorhabditis elegans is a subject of much research, there is no convenient phenotypic readout of caloric restriction that can be applicable to large numbers of worms. This paper describes the distribution of mass densities of populations of C. elegans, from larval stages up to day one of adulthood, using isopycnic centrifugation, and finds that density is a convenient, if complex, phenotypic readout in C. elegans. The density of worms in synchronized populations of wildtype N2 C. elegans grown under standard solid-phase culture conditions was normally distributed, with distributions peaked sharply at a mean of 1.091 g/cm3 for L1, L2 and L3 larvae, 1.087 g/cm3 for L4 larvae, 1.081 g/cm3 for newly molted adults, and 1.074 g/cm3 at 24 hours of adulthood. The density of adult worms under starvation stress fell well outside this range, falling to a mean value of 1.054 g/cm3 after eight hours of starvation. This decrease in density correlated with the consumption of stored glycogen in the food-deprived worms. The density of the worms increased when deprived of food for longer durations, corresponding to a shift in the response of the worms: worms sacrifice their bodies by retaining larvae, which consume the adults from within. Density-based screens with the drug Ivermectin on worms cultured on single plates resulted in a clear bimodal (double-peaked) distribution of densities corresponding to drug exposed and non-exposed worms. Thus, measurements of changes in density could be used to conduct screens on the effects of drugs on several populations of worms cultured on single plates

Collapsible Cubes: Removing Overhangs from 3D Point Clouds to Build Local Navigable Elevation Maps

Elevation maps offer a compact 2 1/2 dimensional model of terrain surface for navigation in field mobile robotics. However, building these maps from 3D raw point clouds con- taining overhangs, such as tree canopy or tunnels, can produce useless results. This paper proposes a simple processing of a ground-based point cloud that identifies and removes overhang points that do not constitute an obstacle for navigation while keeping vertical structures such as walls or tree trunks. The procedure uses efficient data structures to collapse unsupported 3D cubes down to the ground. This method has been successfully applied to 3D laser scans taken from a mobile robot in outdoor environments in order to build local elevation maps for navigation. Computation times show an improvement with respect to a previous point-based solution to this problem.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Interpretación tectonofísica tentativa del caribe colombiano

This paper is a revised version of previous interpretations of the Caribbean structure submitted by the authors to various geological conferences and meetings (mostly unpublished).  The fundamental idea consists in postulating a maximum thickness of 5.000± m. of Cretaceous-Tertiary sediments, in an essentially geosynclinal basin, some 100 km, off shore, in approximate coincidence with the free-air gravity minimum and the magnetic anomaly maximum. The stratigraphic and structural interpretation is based on the correlation originally proposed with the Salamanca drill-hole and available surface gravity and geology information (DURÁN,1964), but corrected with recent JOIDES' Program data.  For the isostatic anomaly a different generalized interpretation is suggested instead, in terms of the new plate tectonics ideas. It is believed that oil-bearing structures may be present off shore, in spite of the negative results obtained heretofore in land, or on shallow shelf.  This reinterpretation (still tentative) is mainly based on partial recent Infermation  from R/V Trident (Rhode Island Univ.) and R/V Conrad (Lamont-Doherty, Columbia Univ.) cruises; on publications and recent discussion and communications,principally with Drs. M. Ewing, M. Talwani, D. Krause and E. Christofferson.El presente trabajo es una interpretación revisada de la que fue sometida por los autores, en mayo del año en curso, al I Congreso Colombiano sobre Recursos Naturales (Bogotá), acerca de la Geología del Caribe.  La idea fundamental de la interpretación consiste en postular un máximo espesor de sedimentos cretácico-terciarios de unos 5.000 metros, aproximadamente a 100 kilómetros mar adentro, en coincidencia aproximada con el mínimo gravimétrico de aire libre y el máximo magnético, correlacionados con la estructura y la estratigrafía continentales, en la Isla de Salamanca. La reinterpretación mantiene la modificación esencial a la sugerencia anterior (DURÀN,1964) sobre el significado de la anomalía isostática negativa, que señalaba el máximo espesor de la columna sedimentaria en coincidencia con aquella. Para la anomalía isostática se sugiere, en cambio, una interpretación diferente, en relación con la tectónica de placas en la comarca, y se corrige la columna de conformidad con los datos de las perforaciones recientes (JOIDES, 1970-71). El trabajo se basa en los datos de los últimos cruceros del R/V Trident (Universidad de Rhode Island) y del R/V Conrad (Lamont-Doherty, Universidad de Columbia), en los cuales los autores tuvieron la oportunidad de participar, en publicaciones, y en comunicaciones personales de los doctores Talwani, Krause y Christofferson, principalmente

Navigability Analysis of Natural Terrains with Fuzzy Elevation Maps from Ground-based 3D Range Scans

Mobile robot navigation through natural terrains is a challenging issue with applications such as planetary exploration or search and rescue. This paper proposes navigability assessment of natural terrains scanned from ground-based 3D laser rangefinders. A continuous model of the terrain is obtained as a fuzzy elevation map (FEM). Based on this model, the proposed solution incorporates terrain navigability both in terms of uncertainties of the 3D input data and slope of the fuzzy surface. Moreover, the paper discusses the application of this method for local path planning. For this purpose, the Bug algorithm has been adapted to compute local paths on the navigable region of the FEM. The method has been applied to actual 3D point clouds on two different experimental sites.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work was partially supported by the Spanish CICYT project DPI 2011-22443 and the Andalusian project PE-2010 TEP-6101

Improving 3D Scan Matching Time of the Coarse Binary Cubes Method with Fast Spatial Subsampling

Morales, J.; Martinez, J.L.; Mandow, A.; Reina, A.J.; Seron, J.; Garcia-Cerezo, A., "Improving 3D scan matching time of the coarse binary cubes method with fast spatial subsampling," 39th Annual Conference of the IEEE Industrial Electronics Society, pp. 4168-4173, 2013 doi:10.1109/IECON.2013.6699804Exploiting the huge amount of real time range data provided by new multi-beam three-dimensional (3D) laser scanners is challenging for vehicle and mobile robot applications. The Coarse Binary Cube (CBC) method was proposed to achieve fast and accurate scene registration by maximizing the number of coincident cubes between a pair of scans. The aim of this paper is speeding up CBC with a fast spatial subsampling strategy for raw point clouds that employs the same type of efficient data structures as CBC. Experimental results have been obtained with the Velodyne HDL-32E sensor mounted on the Quadriga mobile robot on irregular terrain. The influence of the subsampling rate has been analyzed. Preliminary results show a relevant gain in computation time without losing matching accuracy.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Cyclooctyne [60]fullerene hexakis adducts: a globular scaffold for copper-free click chemistry

The synthesis of a new highly symmetric hexakis adduct of C60 appended with 12 cyclooctyne moieties has been carried out. This compound has been used for the copper-free strain-promoted cycloaddition reaction to a series of azides with excellent yields. This strategy for the obtention of clicked adducts of [60]fullerene is of special interest for biological applicationsEuropean Research Council ERC-320441-Chir all carbonMinisterio de Economía y Competitividad CTQ2014-52045-R, CTQ2014-52328-PComunidad Autónoma de Madrid S2013/MIT-28