300 research outputs found
“Caracterización de los sistemas de producción de ovinos de pelo en el suroeste del departamento de Matagalpa 2010”
Con el objetivo de caracterizar los sistemas de producción de ovinos de pelo en el territorio suroeste del departamento de Matagalpa 2010. (Sébaco, Ciudad Darío, San Isidro y Matagalpa). Se aplicó una encuesta a 103 productores que poseen ovinos de pelo, la muestra se definió aleatoriamente utilizando la ecuación planteada por Scheaffer (1987), se utilizó la técnica de muestreo de bola de nieve, planteada por Frey et al (2000). Esta investigación permitió conocer las debilidades y oportunidades en los sistemas de explotación de esta especie promisoria para la zona seca del país. Con los resultados obtenidos de las encuestas se procedió ha elaborar una base de datos en el programa SPSS versión 11.5 en español. Encontrando un predominio del sexo femenino como titulares de las explotaciones ovinas, 58.3% cursó educación primaria, el 98% de las explotaciones cuentan con raza pelibuey, el 100% de las explotaciones realizan destete y monta de forma natural, una media de mortalidad de corderos de 1, alimentan a las ovejas con potrero sin división (81.6%), se suministra pasto de corte, pastoreo, leguminosas y se suplementa sal común 49.5%, aplican vacunas contra ántrax y pierna negra (63.1%), desparasitaciones internas y externas (66%), ambos con una frecuencia de 2 veces al año, en el manejo productivo no se lleva control en la actividad ovina (100%), los equipo e instalaciones son rústicas, los corrales ovinos el son elaborados con alambre y/o madera, techado con plástico y/o zinc (49.51%), en cuanto a asistencia técnica el 58.3% ha recibid
Empirical approach to threshold determination for the delineation of built-up areas with road network data
<div><p>Various approaches have been proposed to address the delineation of built-up areas for a wide range of applications. Recently developed approaches are based on the increasing availability of road network data. However, most approaches have employed one or more parameters to divide built-up from non-built-up areas. Very few studies have discussed how to determine appropriate thresholds for such parameters. This study employed an empirical approach for threshold determination, and validated that the approach is applicable for the delineation of built-up areas using road network data. A series of experiments were designed to investigate the most-appropriate thresholds (determined using a similarity measure) for multiple parameters of three existing approaches (street blocks, grid-based, and kernel density) with regard to different administrative regions and cities/towns. The results show that in most cases, the most-appropriate thresholds or ranges for different subdivisions are either identical or overlap—thus validating the use of the most-appropriate thresholds to delineate built-up areas for one or multiple small subdivisions and, by inference, for a much larger region.</p></div
Most-appropriate thresholds or ranges for the 33 subdivisions of the North Island.
<p>Most-appropriate thresholds or ranges for the 33 subdivisions of the North Island.</p
Dosage compensation in male <i>D</i>. <i>busckii</i>.
<p><b>A.</b> Immunostaining of male and female <i>D</i>. <i>busckii</i> polytene chromosomes with <i>MSL</i>-2 antibody. The neo-X / X chromosome is marked with an arrow, and the male X shows binding of <i>MSL</i>-2 protein. <b>B.</b> Comparison of normalized log2 enrichment level of H4K16ac across genes on different chromosomes. Enrichment level of H4K16ac on X-linked genes (red) is significantly higher (Wilcoxon test, <i>P</i><0.001) than on any other chromosomes, while neo-sex linked genes show a significantly lower enrichment level than autosomes (green), and there is no significant difference between the neo-X (orange) and neo-Y (blue) alleles. <b>C.</b> Enrichment level of H4K16ac is strongly correlated between orthologous genes of <i>D</i>. <i>melanogaster</i> and <i>D</i>. <i>busckii</i>. Genes are color-coded according to chromosomal location. <b>D-E.</b> Metagene profiles of H4K16ac over active (<b>D</b>.) and silent (<b>E</b>.) genes. For neo-sex genes, we defined the expression status by the expression level of neo-X alleles. Note that H4K16ac is significantly more enriched at active X-linked genes, and shows a characteristic 3’ binding bias.</p
Most-appropriate thresholds for the nine administrative districts of the North Island, using the approach based on street blocks.
<p>The most-appropriate threshold for each administrative district is highlighted with a vertical solid line.</p
Parameters and thresholds to be tested using three approaches to the delineation of built-up areas.
<p>Parameters and thresholds to be tested using three approaches to the delineation of built-up areas.</p
Most-appropriate thresholds or ranges for 21 out of the 33 subdivisions of the North Island, using the GlobeLand30-2010 and two different evaluation measures.
<p>Most-appropriate thresholds or ranges for 21 out of the 33 subdivisions of the North Island, using the GlobeLand30-2010 and two different evaluation measures.</p
Functional degeneration of neo-Y genes.
<p><b>A.</b> Composition of neo-Y linked genes. We show numbers of putative functional genes (‘Intact’), genes with premature stop codons (‘PTC’) and/or frameshift (‘Shift’) mutations on the neo-Y. <b>B</b>. Boxplots of gene expression level on each chromosome. We divide neo-sex linked genes according to the functional status of the neo-Y genes: functional (func) neo-Y genes, and their diploid (dpd) neo-X homologs; non-functional (psd) neo-Y genes and their hemizygous (hmz) neo-X homologs. The former group of neo-sex linked genes shows a higher expression level than the latter. <b>C.</b> Allelic expression bias of neo-sex linked genes in male adults. Shown are the log ratios of neo-X expression vs. neo-Y expression along the neo-sex chromosome, with putatively functional neo-Y genes in red and pseudogenes in green. We also plot the loess smooth lines separately for the two categories of genes, in order to show the local variation of the log ratio along the chromosome position. Any genes above 0 have higher neo-X expression relative to the neo-Y. <b>D.</b> Sex-bias expression of neo-sex linked genes. We show the expression difference between sexes for neo-sex linked genes, with neo-X/Y gene expression level combined in male, and only neo-X gene expression in female. <b>E.</b> Correlation between relative neo-sex allelic expression vs. sex-biased expression and relative neo-X expression. Shown are the ratios of neo-X vs. neo-Y expression level for neo-sex linked genes, vs. their expression ratio between sexes (in blue), and the ratio of neo-X expression in male vs. that in female (in orange), as well as their linear regression lines. <b>F.</b> Density plot of the ratios of male neo-sex alleles (neo-X in orange, neo-Y in blue) vs. female expression levels. Assuming an equal expression level between sexes, we expect the distribution of relative neo-X alleles’ expression to be around half of the female expression level (dashed line).</p
Empirical approach to threshold determination for the delineation of built-up areas with road network data - Fig 11
<p>Plot of the area percentages of street blocks in the built-up areas of both the North Island and West Midlands region (a) and eight counties in the West Midlands region (b). The x-axis denotes the different area ranges of street blocks in the built-up areas and the y-axis denotes the total area of street blocks within an area range proportional to that of street blocks within all the (area) ranges.</p
Empirical approach to threshold determination for the delineation of built-up areas with road network data - Fig 2
<p>Three approaches for the delineation of built-up areas: (a) a schematic road network, (b) the approach based on street blocks, (c) the grid-based approach, and (d) the kernel density approach.</p
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