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Search Results: 1 - 10 of 4161 matches for " Patricio Mac Donagh "
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Modelos predictivos de la producción de Pinus taeda empleando variables vinculadas con las podas Yield prediction models using pruning variables for Pinus taeda
Rubén Costas,Patricio Mac Donagh,Elizabeth Weber,Santiago Figueredo
Bosque (Valdivia) , 2006,
Abstract: Con datos de un ensayo de Pinus taeda, con edades entre 4 y 7 a os, se ajustaron a través de regresión lineal múltiple, modelos de producción estáticos de rodal completo, incluyendo variables regresoras asociadas con la intensidad y oportunidad de podas, además de la edad, la densidad y el índice de sitio. Las variables respuestas analizadas fueron el diámetro medio cuadrático, el área basal y el volumen por hectárea. Respecto del área basal fue posible obtener modelos sensibles a las podas realizadas, de mejor calidad de ajuste y de capacidad de predicción que ecuaciones sin variables vinculadas con las podas, que tuvieron excelentes comportamientos estadísticos. Se lograron mejoras de hasta 9,19% de error estándar residual y de 8,99% del estadístico usado para comparar la capacidad de predicción. La utilización de algunas de esas funciones como submodelos dentro de ecuaciones predictivas de diámetro medio cuadrático y volumen por hectárea, relativamente sencillos y con confiabilidad estadística, produjo resultados sensibles a las podas realizadas. Las funciones obtenidas pueden ser usadas como herramientas de cálculo para decidir cuánto y cuándo podar ramas fotosintéticamente activas de acuerdo a los objetivos de producción. Estos modelos son promisorios para el desarrollo de nuevos programas locales de simulación de crecimiento y producción regionales de P. taeda que contemplen a las podas realizadas en los sistemas de producción intensivos. Based on data from an experience in a Pinus taeda plantation, including ages between 4 and 7 years old, multiple linear regressions were adjusted to obtain stand yield functions including regression variables associated with prunes intensity and opportunity, besides age, stand density and site index. The response variables analyzed were quadratic mean diameter, basal area and volume per hectare. The results show that it was possible to improve the prediction quality and accuracy of models of basal area when prune variables are considered, with respect to equations without these variables and with statistical significance. Improvements of 9.19% of the standard residual error and 8.99% of the statistics indicator employed to compare the prediction capacity were obtained. The utilization of some of those functions like sub-models inside equations of quadratic mean diameter and volume by hectare, simple and with good statistics, gives results that are sensitive to prune. These functions could be employed in spreadsheets to decide when and how many green branches to prune in relation to the production objective. The o
ESTRUCTURA POBLACIONAL DE Ocotea puberula EN UN BOSQUE SECUNDARIO Y PRIMARIO DE LA SELVA MIXTA MISIONERA
Silvana Lucia Caldato,Norma Vera,Patricio Mac Donagh
Ciência Florestal , 2002,
Abstract: El objetivo de este trabajo fue estudiar la estructura de la población de Ocotea puberula (Nees et Mart.) Nees (Lauraceae), en bosques de sucesión secundaria y primaria en el Nordeste de Misiones en Argentina, a 26o 15′S y 54o 15′W. Dos parcelas permanentes de muestreo de 3 hectáreas cada una fueron instaladas en el bosque secundario y primario, respectivamente. Cada parcela fue dividida en 75 subparcelas de 20 x 20 m, donde todos los individuos de Ocotea puberula de tama o igual o superior a 20 centímetros de altura fueron registrados. Se estudió la estructura de tama o y la distribución espacial. Ocotea puberula mostró ser una especie secundaria con un número abundante de individuos en la fase de regeneración natural en el bosque secundario, y solamente árboles adultos en el bosque primario. La especie presentó en ambos bosques un patrón agrupado de distribución espacial.
INFLUENCIAS DE LA DENSIDAD Y PODAS SOBRE LA PRODUCCIóN DE Pinus taeda L. A LOS 7 A OS DE EDAD.
Rubén Costas,Patricio Mac Donagh,Elizabeth Weber,Santiago Figueredo
Ciência Florestal , 2005,
Abstract: En un ensayo con 3 niveles de densidad y 12 tratamientos de poda, se evaluaron los efectos de la densidad, la altura de poda, el número de levantes de poda y la interacción entre la densidad y las podas sobre la producción de la masa de Pinus taeda L. a los 7 a os de edad. Las variables evaluadas fueron el diámetro a la altura de pecho medio (DAP), la altura media, el volumen individual, el volumen por unidad de superficie, el área basal, el diámetro máximo sobre mu ón (DMSM), el coeficiente de forma de Girard (CFG), el diámetro de ramas (DRBC) y el ángulo de inserción de las ramas (ARBC) en la base de la copa. En los tratamientos con mayor densidad de plantación se observaron mayores volúmenes por unidad de superficie, área basal y CFG que en los tratamientos con menor densidad. Estos produjeron mayores DAP, volúmenes individuales, DMSM, DRBC y ARBC que los tratamientos con mayores densidades. Los tratamientos con menores alturas finales de poda produjeron mayores DAP, volúmenes individuales, área basal y volúmenes por unidad de superficie que los tratamientos con mayores alturas de poda. Los menores DMSM se obtuvieron con alturas finales de poda de 3,30 m y 4,40 m realizadas a los 4 a os de edad y los mayores DMSM ocurrieron al no efectuarse podas a los 5 a os hasta 5,50 m y 6,60 m. No se encontraron diferencias significativas entre los valores medios de DRBC, ARBC y CFG producidos por los 12 tratamientos de poda. La interacción entre densidad y los tratamientos de poda no fue significativa para ninguna de las variables respuestas.
Modelos predictivos de la producción de Pinus taeda empleando variables vinculadas con las podas
Costas,Rubén; Mac Donagh,Patricio; Weber,Elizabeth; Figueredo,Santiago; Gómez,Claudio; Irschick,Pedro;
Bosque (Valdivia) , 2006, DOI: 10.4067/S0717-92002006000200004
Abstract: based on data from an experience in a pinus taeda plantation, including ages between 4 and 7 years old, multiple linear regressions were adjusted to obtain stand yield functions including regression variables associated with prunes intensity and opportunity, besides age, stand density and site index. the response variables analyzed were quadratic mean diameter, basal area and volume per hectare. the results show that it was possible to improve the prediction quality and accuracy of models of basal area when prune variables are considered, with respect to equations without these variables and with statistical significance. improvements of 9.19% of the standard residual error and 8.99% of the statistics indicator employed to compare the prediction capacity were obtained. the utilization of some of those functions like sub-models inside equations of quadratic mean diameter and volume by hectare, simple and with good statistics, gives results that are sensitive to prune. these functions could be employed in spreadsheets to decide when and how many green branches to prune in relation to the production objective. the obtained models appear interesting for developing new local growth simulation programs of pinus taeda that include prunes applied in intensive silvicultural systems of forest production.
Dynamics of treefall gaps in a harvested forest in Misiones, Northern Argentine Dinámica de claros artificiales en un bosque aprovechado en Misiones, noreste de Argentina
Nardia Maria Luján Bulfe,Franklin Galv?o,Afonso Figueiredo Filho,Patricio Mac Donagh
Pesquisa Florestal Brasileira , 2010, DOI: 10.4336/2012.pfb.64.311
Abstract: This work evaluates the diameter growth of trees species of artificial gaps per ecological groups in a harvested forest considering two systems of harvest. The study was carried out in the Reserva de Biósfera Yabotí, in Misiones, Argentina. Fifteen permanent plots were established, each one with 4 hectares with effective area of measurement of one hectare. The three treatments were: conventional logging, reduced impact logging and control plot. All trees larger than 10 cm of diameter at breast height (DBH) were measured, before (1998) and after the harvest (2006). Eighty-five species were registered. The average DBH diameter growth for all species was 0.41 cm yr-1 in the gap area, and 0.31 cm yr-1 for the control plot. The average diameter growth was 0.36 cm yr-1 for the reduced impact logging and 0.42 cm yr-1 for the conventional logging. In forests with high diversity, ecological groups are an important tool for the management and conservation. The reduced impact logging would be considered a less aggressive alternative for the forests in this region. doi: 10.4336/2010.pfb.30.64.311 Este trabajo evalúa el crecimiento diamétrico de especies arbóreas clasificadas en grupos ecológicos dentro de claros artificiales en un bosque estacional semideciduo aprovechado considerando dos sistemas de cosecha. El estudio fue desarrollado en la Reserva de Biosfera Yabotí, Misiones, Argentina. Se instalaron 15 parcelas permanentes, de cuatro hectáreas cada una, con un área efectiva de medición de una hectárea. Los tratamientos fueron tres: cosecha convencional, cosecha de impacto reducido y parcela testigo. Se registraron todos los ejemplares arbóreos mayores a 10 cm de diámetro a la altura del pecho (DAP) antes (1998) y después de la cosecha (2006). La riqueza florística alcanzó un número de 85 especies. Para el conjunto de especies el crecimiento diamétrico promedio fue de 0,41 cm a o-1 en área de claro y de 0,31 cm.a o-1 en área testigo, siendo el promedio de crecimiento diamétrico de 0,36 cm.a o-1 para impacto reducido y 0,42 cm a o-1 para cosecha convencional. En bosques con alta diversidad florística, se debería considerar a los grupos ecológicos como una herramienta base para el manejo y conservación de los mismos. El aprovechamiento de impacto reducido debería ser considerado como una alternativa menos agresiva para los bosques de la región de Misiones. doi: 10.4336/2010.pfb.30.64.311
Pedagogic Content Knowledge (PCK) in university Biotechnology teaching. The microbial specific growth rate (μ) case
Mauro Ruberto, Lucas Adolfo,Mac Cormack, Walter Patricio,Calabró, Ariel,Rodriguez Talou, Julián
Revista Eureka sobre Ense?anza y Divulgación de las Ciencias , 2012,
Abstract: In this work, a study based on the university student’s conception about microbial specific growth rate (μ) is presented. The study was focused on last year students of the Biochemist career (Buenos Aires University, Argentina). It was developed considering the answers given anonymously by the students when they were spontaneously asked about the meaning of μ. The analysis was focused in the identification of factors which could be related with the students′ ideas about μ, such as the previous work with the subject, the tendency to the functional reduction, the pragmatisms and the possibility of alternative conceptions, but related with a specific field of applied sciences, such as biotechnology. Strategies aiming to the reconstruction of the μ concept were proposed considering these factors. The experiences presented in this work will contribute to the development of the Pedagogical Content Knowledge (PCK) in applied sciences, particularly in biotechnology.
La teoría del caos
Patricio
Política y cultura , 2008,
Abstract:
Spatio-Temporal Prediction of Root Zone Soil Moisture Using Multivariate Relevance Vector Machines  [PDF]
Bushra Zaman, Mac McKee
Open Journal of Modern Hydrology (OJMH) , 2014, DOI: 10.4236/ojmh.2014.43007
Abstract:
Root zone soil moisture at one and two meter depths are forecasted four days into the future. In this article, we propose a new multivariate output prediction approach to root zone soil moisture assessment using learning machine models. These models are known for their robustness, efficiency, and sparseness; they provide a statistically sound approach to solving the inverse problem and thus to building statistical models. The multivariate relevance vector machine (MVRVM) is used to build a model that forecasts soil moisture states based upon current soil moisture and soil temperature conditions. The methodology combines the data at different depths from 5 cm to 50 cm, the largest of which corresponds to the depth at which the soil moisture sensors are generally operational, to produce soil moisture predictions at larger depths. The MVRVM test results for soil moisture predictions at 1 m and 2 m depth on the 4th day are excellent with RMSE = 0.0131 m3/m3 for 1 m; and RMSE = 0.0015 m3/m3 for 2 m forecasted values. The statistics of predictions for 4th day (CoE = 0.87 for 1 m and CoE = 0.96 for 2 m) indicate good model generalization capability and computations show good agreement with actual measurements with R2 = 0.88 and R2 = 0.97 for 1 m and 2 m depths, respectively. The MVRVM produces good results for all four days. Bootstrapping is used to check over/under-fitting and uncertainty in model estimates.
Purging of inbreeding depression within the Irish Holstein-Friesian population
Sinéad Mc Parland, Francis Kearney, Donagh P Berry
Genetics Selection Evolution , 2009, DOI: 10.1186/1297-9686-41-16
Abstract: Inbreeding is defined as the probability that two alleles at any locus are 'identical by descent' [1] and occurs when related individuals are mated. Inbreeding results in an increase in the number of homozygous loci [2], which may lead to an increase in the accumulation of recessive alleles. Mendelian factors unfavourable to fitness are more frequently recessive than dominant for two reasons: firstly, mutations tend to have negative effects on fitness and secondly, because dominant mutations will be quickly selected out of populations. This will lead to an accumulation of deleterious recessive alleles [2]. The loss in performance and vitality associated with inbreeding is termed "inbreeding depression" [3] and has generally been shown to be unfavourable [4].It has been considered for different traits that dominance [3], overdominance [5], and epistatic effects [6] influences inbreeding depression. Where the genes are governed by dominance, inbreeding depression is caused by an increase in the number of genes with homozygous deleterious recessive genotypes and the decline in performance is expected to be linear with respect to the inbreeding coefficient [6]. Where traits are governed by overdominance, heterozygotes perform better than either homozygote, thus as inbreeding increases the number of homozygous loci, the proportion of advantageous heterozygous loci decreases. Epistasis occurs when an allele at one locus has an effect on an allele at another locus. Where epistatic interactions exist, a non-linear effect on performance is expected with respect to inbreeding [7]. The non-linear interactions are explained by the interaction deviation of double or multiple heterozygotes [8].Regardless of the mechanisms underlying inbreeding depression, the effects of inbreeding are not consistent across populations or even sub-populations. Thus the level of inbreeding depression experienced is dependent, amongst other factors, on the genetic load of individuals [9].Purging of
[η5-(Phenylethynyl)cyclopentadienyl](η4-tetraphenylcyclobutadiene)cobalt(I)
Donagh Courtney,Anthony R. Manning,C. John McAdam,Jim Simpson
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811016928
Abstract: In the title compound, [Co(C13H9)(C28H20)], the Co atom is sandwiched between cyclopentadienyl and cyclobutadienyl rings that are inclined at a dihedral angle of 2.6 (3)°. The four phenyl rings are tilted with respect to the cyclobutadienyl plane so that the C4Ph4 unit constitutes a four-bladed propeller. The phenyl ring of the phenyl-alkyne substituent is inclined to the cyclopentadienyl ring at an angle of 34.92 (18)°. The crystal structure is stabilized solely by C—H...π interactions which generate a three-dimensional network.
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