29 research outputs found

    Parsimony and omitted factors: the airline model and the Census X-11 assumptions

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    El tipo de modelo Arima para el que el metodo de ajuste estacional X-11 es adecuado se ha identificado como (1-L)(1-L12)Xt=G(L)at, (CX), en donde G(L) es de orden 26. En este documento se aproxima el modelo CX mediante un modelo Arima (1,1,2)(0,1,1), con raices complejas en el factor MA regular y se demuestra que tal modelo tiene un factor de estabilidad -mayor potencia espectral en frecuencias bajas- que no esta presente en el "modelo de lineas aereas" propuesto por Box y Jenkins

    Respuesta ósea al implante del compuesto beta-fosfato tricálcico-colágeno (ß-ftc-c). Estudio «in vivo» en conejos

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    Se ha estudiado la correlación entre los hallazgos histológicos y las imágenes radiológicas de un compuesto de beta-fosfato tricálcico y colágeno (ß-FTC-C) después de su implantación en defectos óseos creados experimentalmente en 21 conejos de 4 Kg de peso medio. Bajo anestesia general los defectos óseos creados en ambos fémures se rellenaron con un cilindro de 4,5 x 6 mm del compuesto. Los animales fueron sacrificados a la semana y 1, 2, 4 y 12 meses del postoperatorio. Las muestras obtenidas fueron sometidas a estudio radiográfico e histológico. Microscópicamente se comprobó que el compuesto a lo largo del período de implantación sufrió un proceso de reabsorción progresiva mediado por células de estirpe macrofágica y que se correspondió con una disminución de la densidad radiológica y cambios en su morfología. A los doce meses del postoperatorio se observaron escasos restos del material, hecho que se corresponde con la desaparición del implante en la placa radiográfica.The correlation between histologic and radiological findings was studied after implantation of a composite (ß-FTC-C) into osseus defects which were experimentally induced in 21 rabbits. Under general anaesthetic osseus defects were made in both femurs and filled in with a 4,5 x 6 mm composite cylinder. The animals were killed at the first week and, one, two, four and twelve months after surgery. X-ray study and microscopic examination were made in all the specimens. Troughout the implantation period, it was microscopically proven that the composite showed a progressive reabsortion process, mediated by cells of macrophagus lineage. A decrease in radiologic density and changes in its morphology were also observed. At the end of the study (twelve months), limited traces of the material could be seen, in correlation with the images of the X-ray films which revealed the total absence of the composite implant

    Factores asociados con las exposiciones percutáneas en el personal sanitario del Servicio Murciano de Salud (SMS) 2005-2010

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    Objective Our objetive is to reduce the risk of ARB with bloody in SMS / year, by analyzing the working conditions associated with Biohazard accidents occurred in the SMS during 2005 to 2010 and proposing appropriate preventive measures according to data obtained. Materials and methods This is a descriptive study of the ARB retrosprectivo risk hematic Service reported to Occupational Health and Safety of the SMS of the year 2005-2010. Results The 92% of ARB were at risk hematic. The most common features were: percutaneous exposure to blood, in fingers with a hollow needle, operating / suturing. The most frequently indicated was "bad habits”. Conclusions Based on the data obtained suggest preventive measures necessary to develop a regional legislation on the use of biosafety equipment and staff training in prevention, not only in terms of knowledge, but aspects including aptitude and attitude towards prevention. We also want to emphasize the need to develop biosafety suture material and surgical material.Objetivo Nuestro objetivo final es reducir el número de accidentes por riesgo biológico con contenido hemático en el Servicio Murciano de Salud (SMS), a través del análisis las condiciones de trabajo asociadas a dichos accidentes ocurridos en el SMS durante el periodo 2005-2010 y la propuesta de medidas preventivas oportunas según los datos obtenidos. Material y método Se trata de un estudio descriptivo retrosprectivo de los ARB con riesgo hemático comunicados al servicio de prevención de riesgos laborales del SMS durante el periodo 2005-2010. Resultados De los ARB estudiados, el 92% han sido de riesgo hemático, siendo el fluido más frecuentemente implicado la sangre, principalmente por lesiones en los dedos. Destaca entre los objetos responsables de los accidentes la aguja hueca. Entre las actividades que se estaban realizando cuando ocurrió el accidente sobresale “operando/ instrumentando, siendo “los hábitos incorrectos” la causa que aparece reflejada más frecuentemente. Conclusiones En base a los datos obtenidos se proponen como medidas preventivas necesarias el desarrollo de una legislación autonómica sobre el uso de material de bioseguridad y la formación del personal en procedimientos de trabajo seguros, pero no sólo a nivel de conocimientos, sino incluyendo aspectos aptitud y actitud hacia la prevención. También queremos destacar la necesidad de desarrollar material de bioseguridad para suturas y en los quirófanos

    Molecular Ecology (2001) 10, 1733--1742

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    The genetic structure of Apis mellifera populations from the Canary Islands has been assessed by mitochondrial (restriction fragment length polymorphisms of the intergenic transfer RNA leu -COII region) and nuclear (microsatellites) studies. These populations show a low level of genetic variation in terms of average number of alleles and degree of heterozygosity

    High levels of chromosomal differentiation in Euchroma gigantea L. 1735 (Coleoptera, Buprestidae)

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    Euchroma gigantea was karyotypically studied using conventional staining, C-banding, silver nitrate staining and ribosomal fluorescent in situ hybridization (rDNA FISH). Broad wide autosomal polymorphism and a complex sex determination system were found in this beetle. Karyotype complements ranging from 2n = 32, X1X2X3Y1Y2Y3 to 2n = 36,X1X2X3Y1Y2Y3 were detected in the sample analyzed. Punctiform supernumerary chromosomes were present in the different karyotypes. The karyotypic evolution of Brazilian E. gigantea may have taken two directions, reduction in the diploid number of 2n = 36 to 24 through centric fusions or 2n = 24 to 36 due to chromosomal fissions. In addition, pericentric inversions were also involved. The complex multiple sex mechanism of this species seems to be old and well established since it is found in specimens from different populations. Small pericentromeric blocks of constitutive heterochromatin were located on the autosomes and terminal blocks were also found on some small pairs. The sex chromosomes showed larger constitutive heterochromatin blocks. Silver nitrate staining during prophase I of meiosis showed labeling of the sex chromosome chain. However, the rDNA sites could only be precisely determined by FISH, which permitted the identification of these ribosomal sites on chromosomes X1 and X2 of this species

    Physical mapping of ribosomal DNA and genome size in diploid and polyploid North African Calligonum species (Polygonaceae)

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    38 p., tablas, gráf.Most Calligonum species are desert plants, characteristic of the Saharan bioclimatic region. All species karyologically analyzed until present have the basic chromosome number x = 9 and comprise diploids, triploids and tetraploids. The Tunisian flora comprises diploid Calligonum arich and C. azel, of restricted distribution, and the tetraploid C. comosum with wider distribution. Analyses of their karyotypes and polyploidisation-linked rDNA changes by orcein staining, fluorochrome banding with chromomycin A3 and fluorescent in situ hybridisation with 5S and 26S ribosomal DNA probes have been performed. We report the chromosome number for Calligonum arich (2n = 18) as well as the diploid level for C. comosum for the first time. Chromosome counts have also verified the earlier described tetraploid cytotype (2n = 36) of C. comosum. A general pattern of six GC-rich bands as well as two 35S sites and four 5S sites is described for Calligonum species at the diploid level although there is intraspecific variation regarding the site number in a second type of C. comosum, with one pair of 35S rDNA sites and two pairs of 5S rDNA sites. The tetraploid cytotype of C. comosum has undergone locus loss and genome downsizing. Genome size assessments confirmed previous data. Nonetheless, statistically significant differences were found depending on the type of tissue used for estimation. Measurements from seeds had always larger values than from leaves. The presence of cytosolic compounds in leaves, interfering with DNA staining, is discussed as a possible cause of the differences.This work was supported by the Dirección General de Investigación Científica y Técnica, government of Spain (CGL2010-22234-C02-01/BOS and CGL2010-22234-C02-02/BOS) and the Generalitat de Catalunya, government of Catalonia (‘‘Ajuts a grups de recerca consolidats’’, 2009SGR0439). SG and OH benefitted from Juan de la Cierva postdoctoral contracts of the Ministry of Economy and Competitiveness, government of Spain.Peer reviewe
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