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1.
Environ Sci Pollut Res Int ; 30(17): 50174-50197, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36790704

RESUMEN

Recycling agents provide better additions of reclaimed asphalt pavement (RAP) in the production of new asphalt mixtures. Alternative and residual materials that have the potential as asphalt binder viscosity reducers have gained visibility in the field of paving due to the perspective of circular economy in recycled mixtures. Soybean oil sludge fatty acid is a material produced from soybean oil sludge, a waste generated in the soybean oil refining step. Thus, this paper investigated the physical, chemical, and rheological effects of the asphalt binder PG 64-XX modified by the fatty acid of soybean oil sludge in the contents of 6% and 7% by weight of the binder. The modified binder samples were submitted to penetration tests, softening point, rotational viscosity, performance grade (PG), before and after short-term aging (RTFO), and multiple stress creep and recovery (MSCR). A control asphalt mixture and recycled asphalt mixtures produced with 40% RAP and fatty acid-modified binders were subjected to tensile strength, induced moisture damage, resilient modulus, and fatigue life. A Student's t statistical test verified the significance of the data, as well as the estimation of production costs of these asphalt mixtures. The use of the fatty acid significantly reduced the stiffness and viscosity of the control asphalt binder, decreasing the mixing temperatures at 14 °C and 17 °C to 6% and 7%, respectively. Using higher fatty acid contents from soybean oil sludge significantly improved the performance of recycled mixtures in tensile strength, moisture damage, and fatigue life. The production cost of recycled asphalt mixtures was lower than that of the control mixture.


Asunto(s)
Aguas del Alcantarillado , Aceite de Soja , Ácidos Grasos , Materiales de Construcción
2.
Ciênc. rural (Online) ; 48(3): e20170496, 2018. tab
Artículo en Inglés | LILACS | ID: biblio-1045078

RESUMEN

ABSTRACT: Asian soybean rust is an important disease that has deeply troubled farmers and researchers since it was first reported. The causal agent, biotrophic fungus Phakopsora pachyrhizi Sydow & P. Sydow, has found extremely favorable conditions for its dissemination in Brazil. The most characteristic symptom of infection appears in the leaves, initially on the adaxial leaf surface, as small angular points less than 1mm in diameter, together with gray-colored uredospores (spores). Management involves a set of practices that guarantee coexistence between the plant and the pathogen without significant damage to the crop. The objective of this research was to evaluate tolerance to Asian rust by estimating losses caused by natural infection in the field. Experiments with generation F4 (2014/15) plants were established in a randomized blocks design with four replicates, with two types of genotypes (crosses and parents) and two schemes for disease management using fungicides. For analysis of the data, a test was applied on two dependent samples to verify the significance of the estimate of the rust effect. With regard to grain yield and tolerance, the most outstanding crosses were 104 (USP14-01-20 × EMGOPA313) and 149 (USP93-05.552 × EMGOPA313). Crosses 147 (USP93-05552 × PI153.282) and 137 (USP70.108 × PI153.282) were graded as tolerant in the evaluation of both yield reduction and seed size. We found evidence of tolerance to Asian rust in both crosses and parents. The statistical test revealed the significance of the rust effect estimates in soybean.


RESUMO: A ferrugem asiática da soja é a doença que mais tem preocupado os produtores e pesquisadores desde sua primeira evidência. Ela é causada pelo fungo biotrófico Phakopsora pachyrhizi Sydow & P. Sydow que encontrou condições extremamente favoráveis para a sua disseminação no Brasil. O sintoma mais característico apresenta-se nas folhas, inicialmente na face adaxial, como pequenos pontos angulares com menos de um milímetro de diâmetro, juntamente com os uredósporos (esporos) de coloração acinzentada. O manejo se dá por meio de um conjunto de práticas que garanta a boa convivência entre a planta e o patógeno e sem que ocorra danos significativos à lavoura. O trabalho objetivou avaliar a tolerância à ferrugem asiática estimando as perdas causadas pela infestação natural a campo. Os experimentos com a geração F4 (2014/15) foram delineados em blocos ao acaso com quatro repetições. Foram realizadas categorias de experimentos, envolvendo dois tipos de genótipos (cruzamentos e genitores) e dois tipos de manejos de doenças com fungicidas. Para a análise dos dados foi aplicado um teste, para duas amostras dependentes, a fim de verificar a significância da estimativa do efeito ferrugem. Considerando a produtividade e a tolerância, os cruzamentos mais importantes foram 104 (USP 14-01-20 x EMGOPA 313) e 149 (USP 93-05.552 x EMGOPA 313). Os cruzamentos 147 (USP 93-05.552 x PI 153.282) e 137 (USP 70.108 x PI 153.282) foram tolerantes tanto na avaliação de redução da produtividade e do tamanho de semente. Houveram evidências de tolerância à ferrugem asiática nos cruzamentos e nos genitores. O teste estatístico revelou a significância das estimativas de efeito ferrugem em soja.

3.
Ciênc. rural (Online) ; 48(3): 1-9, 2018. tab
Artículo en Inglés | VETINDEX | ID: biblio-1480082

RESUMEN

Asian soybean rust is an important disease that has deeply troubled farmers and researchers since it was first reported. The causal agent, biotrophic fungus Phakopsora pachyrhizi Sydow & P. Sydow, has found extremely favorable conditions for its dissemination in Brazil. The most characteristic symptom of infection appears in the leaves, initially on the adaxial leaf surface, as small angular points less than 1mm in diameter, together with gray-colored uredospores (spores). Management involves a set of practices that guarantee coexistence between the plant and the pathogen without significant damage to the crop. The objective of this research was to evaluate tolerance to Asian rust by estimating losses caused by natural infection in the field. Experiments with generation F4 (2014/15) plants were established in a randomized blocks design with four replicates, with two types of genotypes (crosses and parents) and two schemes for disease management using fungicides. For analysis of the data, a test was applied on two dependent samples to verify the significance of the estimate of the rust effect. With regard to grain yield and tolerance, the most outstanding crosses were 104 (USP14-01-20 × EMGOPA313) and 149 (USP93-05.552 × EMGOPA313). Crosses 147 (USP93-05552 × PI153.282) and 137 (USP70.108 × PI153.282) were graded as tolerant in the evaluation of both yield reduction and seed size. We found evidence of tolerance to Asian rust in both crosses and parents. The statistical test revealed the significance of the rust effect estimates in soybean.


A ferrugem asiática da soja é a doença que mais tem preocupado os produtores e pesquisadores desde sua primeira evidência. Ela é causada pelo fungo biotrófico Phakopsora pachyrhizi Sydow & P. Sydow que encontrou condições extremamente favoráveis para a sua disseminação no Brasil. O sintoma mais característico apresenta-se nas folhas, inicialmente na face adaxial, como pequenos pontos angulares com menos de um milímetro de diâmetro, juntamente com os uredósporos (esporos) de coloração acinzentada. O manejo se dá por meio de um conjunto de práticas que garanta a boa convivência entre a planta e o patógeno e sem que ocorra danos significativos à lavoura. O trabalho objetivou avaliar a tolerância à ferrugem asiática estimando as perdas causadas pela infestação natural a campo. Os experimentos com a geração F4 (2014/15) foram delineados em blocos ao acaso com quatro repetições. Foram realizadas categorias de experimentos, envolvendo dois tipos de genótipos (cruzamentos e genitores) e dois tipos de manejos de doenças com fungicidas. Para a análise dos dados foi aplicado um teste, para duas amostras dependentes, a fim de verificar a significância da estimativa do efeito ferrugem. Considerando a produtividade e a tolerância, os cruzamentos mais importantes foram 104 (USP 14-01-20 x EMGOPA 313) e 149 (USP 93-05.552 x EMGOPA 313). Os cruzamentos 147 (USP 93-05.552 x PI 153.282) e 137 (USP 70.108 x PI 153.282) foram tolerantes tanto na avaliação de redução da produtividade e do tamanho de semente. Houveram evidências de tolerância à ferrugem asiática nos cruzamentos e nos genitores. O teste estatístico revelou a significância das estimativas de efeito ferrugem em soja.


Asunto(s)
Fungicidas Industriales , Fitomejoramiento , Phakopsora pachyrhizi , Glycine max/inmunología , Tolerancia Inmunológica
4.
Ci. Rural ; 48(3): 1-9, 2018. tab
Artículo en Inglés | VETINDEX | ID: vti-733650

RESUMEN

Asian soybean rust is an important disease that has deeply troubled farmers and researchers since it was first reported. The causal agent, biotrophic fungus Phakopsora pachyrhizi Sydow & P. Sydow, has found extremely favorable conditions for its dissemination in Brazil. The most characteristic symptom of infection appears in the leaves, initially on the adaxial leaf surface, as small angular points less than 1mm in diameter, together with gray-colored uredospores (spores). Management involves a set of practices that guarantee coexistence between the plant and the pathogen without significant damage to the crop. The objective of this research was to evaluate tolerance to Asian rust by estimating losses caused by natural infection in the field. Experiments with generation F4 (2014/15) plants were established in a randomized blocks design with four replicates, with two types of genotypes (crosses and parents) and two schemes for disease management using fungicides. For analysis of the data, a test was applied on two dependent samples to verify the significance of the estimate of the rust effect. With regard to grain yield and tolerance, the most outstanding crosses were 104 (USP14-01-20 × EMGOPA313) and 149 (USP93-05.552 × EMGOPA313). Crosses 147 (USP93-05552 × PI153.282) and 137 (USP70.108 × PI153.282) were graded as tolerant in the evaluation of both yield reduction and seed size. We found evidence of tolerance to Asian rust in both crosses and parents. The statistical test revealed the significance of the rust effect estimates in soybean.(AU)


A ferrugem asiática da soja é a doença que mais tem preocupado os produtores e pesquisadores desde sua primeira evidência. Ela é causada pelo fungo biotrófico Phakopsora pachyrhizi Sydow & P. Sydow que encontrou condições extremamente favoráveis para a sua disseminação no Brasil. O sintoma mais característico apresenta-se nas folhas, inicialmente na face adaxial, como pequenos pontos angulares com menos de um milímetro de diâmetro, juntamente com os uredósporos (esporos) de coloração acinzentada. O manejo se dá por meio de um conjunto de práticas que garanta a boa convivência entre a planta e o patógeno e sem que ocorra danos significativos à lavoura. O trabalho objetivou avaliar a tolerância à ferrugem asiática estimando as perdas causadas pela infestação natural a campo. Os experimentos com a geração F4 (2014/15) foram delineados em blocos ao acaso com quatro repetições. Foram realizadas categorias de experimentos, envolvendo dois tipos de genótipos (cruzamentos e genitores) e dois tipos de manejos de doenças com fungicidas. Para a análise dos dados foi aplicado um teste, para duas amostras dependentes, a fim de verificar a significância da estimativa do efeito ferrugem. Considerando a produtividade e a tolerância, os cruzamentos mais importantes foram 104 (USP 14-01-20 x EMGOPA 313) e 149 (USP 93-05.552 x EMGOPA 313). Os cruzamentos 147 (USP 93-05.552 x PI 153.282) e 137 (USP 70.108 x PI 153.282) foram tolerantes tanto na avaliação de redução da produtividade e do tamanho de semente. Houveram evidências de tolerância à ferrugem asiática nos cruzamentos e nos genitores. O teste estatístico revelou a significância das estimativas de efeito ferrugem em soja.(AU)


Asunto(s)
Phakopsora pachyrhizi , Glycine max/inmunología , Fungicidas Industriales , Fitomejoramiento , Tolerancia Inmunológica
5.
Environ Technol ; 37(6): 681-93, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26235832

RESUMEN

Biofiltration of volatile organic compounds is still considered an emerging technology. Its reliability remains questionable as no data is available regarding process intrinsic repeatability. Herein, two identically operated toluene biofiltration systems are comprehensively compared, during long-term operation (129 days). Globally, reactors responded very similarly, even during transient conditions, with, for example, strong biological activities from the first days of operation, and comparable periods of lower removal efficiency (81.2%) after exposure to high inlet loads (140 g m(-3) h(-1)). Regarding steady states, very similar maximum elimination capacities up to 99 g m(-3) h(-1) were attained. Estimation of the process repeatability, with the paired samples Student's t-test, indicated no statistically significant difference between elimination capacities. Repeatability was also established for several descriptors of the process such as the carbon dioxide and biomass production, the pH and organic content of the leachates, and the moisture content of the packing material. While some parameters, such as the pH, presented a remarkably low divergence between biofilters (coefficient of variability of 1.4%), others, such as the organic content of the leachates, presented higher variability (30.6%) due to an uneven biomass lixiviation associated with stochastic hydrodynamics and biomass repartitions. Regarding process efficiency, it was established that less than 10% of fluctuation is to be expected between the elimination capacities of identical biofilter set-ups. A further statistical comparison between the first halves of the biofilter columns indicated very similar coefficients of variability, confirming the repeatability of the process, for different biofilter lengths.


Asunto(s)
Filtros de Aire , Contaminantes Atmosféricos/metabolismo , Contaminación del Aire/prevención & control , Reactores Biológicos , Tolueno/metabolismo , Óxido de Aluminio/química , Dióxido de Carbono/metabolismo , Aguas del Alcantarillado/microbiología , Dióxido de Silicio/química
6.
Microarrays (Basel) ; 3(4): 340-51, 2014 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-27600352

RESUMEN

Microarray data analysis typically consists in identifying a list of differentially expressed genes (DEG), i.e., the genes that are differentially expressed between two experimental conditions. Variance shrinkage methods have been considered a better choice than the standard t-test for selecting the DEG because they correct the dependence of the error with the expression level. This dependence is mainly caused by errors in background correction, which more severely affects genes with low expression values. Here, we propose a new method for identifying the DEG that overcomes this issue and does not require background correction or variance shrinkage. Unlike current methods, our methodology is easy to understand and implement. It consists of applying the standard t-test directly on the normalized intensity data, which is possible because the probe intensity is proportional to the gene expression level and because the t-test is scale- and location-invariant. This methodology considerably improves the sensitivity and robustness of the list of DEG when compared with the t-test applied to preprocessed data and to the most widely used shrinkage methods, Significance Analysis of Microarrays (SAM) and Linear Models for Microarray Data (LIMMA). Our approach is useful especially when the genes of interest have small differences in expression and therefore get ignored by standard variance shrinkage methods.

7.
Rev Med Inst Mex Seguro Soc ; 51(3): 300-3, 2013.
Artículo en Español | MEDLINE | ID: mdl-23883459

RESUMEN

Among the test to show differences between means, the Student t test is the most characteristic. Its basic algebraic structure shows the difference between two means weighted by their dispersion. In this way, you can estimate the p value and the 95 % confidence interval of the mean difference. An essential feature is that the variable from which the mean is going to be calculated must have a normal distribution. The Student t test is used to compare two unrelated means (compared between two maneuvers), this is known as t test for independent samples. It is also used to compare two related means (a comparison before and after a maneuver in just one group), what is called paired t test. When the comparison is between more than two means (three or more dependent means, or three or more independent means) an ANOVA test (or an analysis of variance) it is used to perform the analysis.


Dentro de las pruebas para demostrar diferencia de medias, la más característica es la t de Student. La estructura algebraica base de esta prueba muestra la diferencia ponderada del promedio de una variable menos el promedio de otra entre su dispersión; de esta manera, se puede calcular el valor de p y el intervalo de confianza de 95 % para dicha diferencia de medias. Una característica indispensable es que la variable de la cual se va a calcular la media tenga distribución normal. La prueba t de Student igual se utiliza para dos medias de muestras no relacionadas (se compara entre dos maniobras) a lo que se le conoce como prueba t para muestras independientes, o para dos medias de muestras relacionadas (una comparación de antes y después de una maniobra), a lo que se le denomina t pareada. Cuando la comparación va más allá de dos medias (tres medias dependientes, o tres medias de grupos distintos) el análisis a realizar es un ANOVA (analysis of variance, por sus siglas en inglés).


Asunto(s)
Análisis de Varianza , Investigación Biomédica , Modelos Estadísticos , Juicio
8.
Int. j. morphol ; 28(4): 1069-1074, dic. 2010. ilus
Artículo en Inglés | LILACS | ID: lil-582890

RESUMEN

The human body is composed of lean tissues that are metabolically active, and fat tissue that is not metabolically active, but is an essential part of human body. Training is a significant factor affecting body composition, performance, as well and physiological parameters. The aim of this study was through changeable of 13 measured anthropometrical variables, to research the influence of different sports in body composition. The anthropometrical tests were done on 90 basketball players and 512 footballers from Kosova. The gained results were analyzed in terms of basic statistical parameters, T-test, and Canonical Discriminant Analysis. T-test shows that basketballers and footballers have realized significant differences in almost all measured variables. Canonical Discriminative Analysis indicates the characteristics of tested sportsmen: The basketballers are taller and heavier than footballers, as well they have the greater bodily volume, and more skinfold thickness, compared with footballers. It seems that the bodily volume of the tested basketballers has been influenced by the elements of basketball, than the bodily volume of footballers by the elements of football. As for subcutaneous adipose tissue that is less disperse on the footballers body compared with basketballers, could be explained with different ratio between aerobic and anaerobic demands of different sports.


El cuerpo humano se compone de tejido blando que es metabólicamente activo y tejido graso que no es metabólicamente activo, pero es una parte esencial del cuerpo. El entrenamiento es un factor significativo que afecta la composición corporal, el rendimiento y los parámetros fisiológicos. El objetivo de este estudio fue investigar la influencia de los diferentes deportes en la composición corporal, a través de la medición de 13 variables antropométricas. Las pruebas antropométricas fueron realizadas en 90 jugadores de baloncesto y 512 jugadores de fútbol de la ciudad de Kosovo. Los resultados obtenidos fueron analizados estadísticamente utilizándose el T-test y el análisis discriminante canónico. El T-test mostró que los jugadores de baloncesto y los futbolistas poseen diferencias significativas en casi todas las variables estudiadas. El análisis discriminante canónico de las características de los deportistas evaluados mostraron que: los jugadores de baloncesto son más altos y de mayor peso que los futbolistas y tenían mayor volumen corporal y pliegues cutáneos en comparación con los futbolistas. El volumen corporal de los jugadores de baloncesto han sido más influenciados por los elementos del baloncesto, que el volumen corporal de los futbolistas por los elementos del fútbol. En cuanto a tejido adiposo subcutáneo, es menos disperso en el cuerpo de los futbolistas comparado con jugadores de baloncesto, lo que podría explicarse por una relación diferente entre las demandas aeróbica y anaeróbica exigidas en los diferentes deportes.


Asunto(s)
Humanos , Masculino , Adulto , Baloncesto , Composición Corporal , Grosor de los Pliegues Cutáneos , Fútbol , Antropometría , Análisis Discriminante
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