Genetic inbreeding depression load for fertility traits in Pura Raza Española mares

Fertility is a key factor in the economic success of horse farms. However, it has received little attention due to the difficulty of measuring fertility objectively. Since its studbook creation (1912), the Pura Raza Española (PRE) breed has been a closed population and become high in-bred resulting in inbreeding depression (poor phenotypic values). Nevertheless, heterogeneous effects of inbreeding depression have been detected among founders and nonfounders. The aims of this study were (1) to analyze the genetic parameters for reproductive traits in mares of the PRE horse breed and (2) to estimate, for the first time, the inbreeding depression load associated with common ancestors of the breed. A total of 22, 799 mares were analyzed. Heritability estimates ranged from 0.05 (interval between first and second foaling) to 0.16 (age at first foaling), whereas inbreeding depression load ratios ranged from 0.06 (parturition efficiency at 6th foaling) to 0.17 (age at first foaling), for a partial inbreeding coefficient of 10%. Although heritability is related to the variability expressed in the population, inbreeding depression load ratios measure the potential variability, whether expressed in the population or not. Most correlations between additive and inbreeding depression load genetic values were significant (P < 0.001) and of low to moderate magnitude. Our results confirm that individual inbreeding depression loads allow us to select horses that have a genetic value resistant to the deleterious effects of inbreeding. © The Author(s) 2021. Published by Oxford University Press on behalf of the American Society of Animal Science

Simultaneous obtention of multicomponent ferroalloy and slag from black sands for the development of electrical arc welding consumables

10 páginas, 3 figuras, 8 tablas.[ES] En este trabajo se expone una caracterización química y mineralógica de las arenas negras del placer Mejías de Sagua de Tánamo, el más importante placer litoral de playa del noroeste de Cuba Oriental. A partir de estas caracterizaciones se desarrolla una estrategia de cálculo para la confección de la carga metalúrgica, que permite obtener, simultáneamente, al ser procesada por reducción carbotérmica en un homo de arco eléctrico, una ferroaleación multicomponente y una escoria útil para la confección de consumibles de soldadura por arco eléctrico. El polvo de la escoria obtenida se aglomera con vidrio líquido. Los pelets resultantes y su comportamiento en la soldadura automática por arco sumergido (SAW), presentan propiedades metalúrgicas y tecnológicas que satisfacen los requisitos de una matriz de un fundente aglomerado. La composición química de la ferroaleación multicomponente está constituida por elementos metálicos: vanadio, cromo, molibdeno, titanio y niobio (V, Cr, Mo, Ti y Nb) de alto valor metalúrgico y aleante, apropiada para la formulación de cargas aleantes de consumibles tanto para la soldadura manual (SMAW) como para la SAW.[EN] In this paper, chemical and mineralogical characterizations of the black sands of the Mejias placer of Sagua de Tánamo (the most important beach littoral placer of the northwest of oriental Cuba) are exposed. Starting from these characterizations a calculation strategy is developed for the making of the metallurgical load that allows to obtain simultaneously, when processed by carbothermic reduction in an electrical arc furnace, a multicomponent ferroalloy and a useful slag for the making of electric arch welding consumables. The powder of the obtained slag is agglomerated with liquid glass. The resulting pellets, due to their behavior on the submerged arc welding (SAW) present technological and metallurgical properties that correspond with the requirements of an agglomerated flux matrix. The chemical composition of the multicomponent ferroalloy is constituted by metallic elements of high metallurgical and alloyed values (V, Cr, Mo, Ti, Nb). It is appropriate for the formulation of consumables for manual welding (SMAW) and SAW, as well.Peer reviewe

Use of refractory chromites for obtaining fluxes amassed employed in submerged arc welding (SAW)

11 páginas, 2 figuras, 8 tablal.[ES] En el presente trabajo se obtienen ferrocromo de alto carbono (ferrocromo de carga) y escorias a partir del proceso de reducción de cromitas refractarias. Mediante la utilización de un diseño de experimento de relaciones entre componentes, se estudia la obtención de aleaciones y escorias. La composición química de ambas garantiza su aplicación para la conformación de cargas aleantes y matrices de fundentes aglomerados, para el relleno superficial mediante soldadura automática por arco sumergido (SAW). El proceso de fusión-reducción se realiza en un horno eléctrico de arco.[EN] In the present work high carbon ferrochrome (load ferrochrome) and slags are obtained, starting frora the métallurgie reductive processing of refractory chromites. The obtaining of alloys and slags is studied using an experiment design based in the relationships among components. The chemical compositions of alloys and slags guarantee their application for the conformation of alloys loads and matrix fluxes amassed for the superficial filling by means of submerged arc welding (SAW). The melting-reduction process is carried out in an electric arc furnace.Peer reviewe

Influencia del tamaño, la variedad y la proporción de sexos en la producción de huevos de tilapia (Oreochromis spp) en un sistema tropical intensivo al aire libre

The effect of the variety, size of the females and sex ratio in the production of eggs of Chitralada (CH: Oreochromis niloticus) and Taiwanese red (TR: O. mossambicus x O. niloticus) in outdoor concrete tanks were evaluated in a fish production unit located in the Andean foothills of the state of Trujillo, Venezuela. A 2x2x3 factorial arrangement design was used: two varieties (CH and TR), two sizes (large and small) and three female male proportions (1:1, 2:1 and 3:1). CH females produced greater volume and mass of eggs, spawned 2.4-fold more and were more fertile than TR (p&lt;0.01). Large tilapia had 1.6-fold fewer spawning (p&lt;0.05) and produced fewer eggs per 100 females than small ones (p&lt;0.01). In general, the F:M ratio did not affect the reproductive variables. The small females of both varieties had a higher number of spawning than the large ones, and the large CH tilapia spawned 3.9 times more than the TR of the same size (p&lt;0.01), while in the small ones this difference was only 1.7 times (p&lt;0.05). The large CH tilapias were reproductively more efficient than the females of the same category of the TR variety. In conclusion, the CH tilapia and the smaller size and weight females were reproductively more efficient than those of the TR variety and the larger ones. Regardless of the variety, the reproductive activity was not affected by the proportions between females and males.Se evaluó el efecto de la variedad, tamaño de las hembras y relación hembra macho en la producción de huevos de tilapias Chitralada (CH: Oreochromis niloticus) y Taiwanesa roja (TR: O. mossambicus x O. niloticus), en tanques de concreto al aire libre, en una unidad de producción piscícola localizada en el Piedemonte Andino del estado Trujillo, Venezuela. Se utilizó un diseño en arreglo factorial 2x2x3: dos variedades (CH y TR), dos tamaños (grades y pequeñas) y tres proporciones hembra macho (1:1, 2:1 y 3:1). Las hembras CH produjeron mayor volumen y masa de huevos, desovaron 2.4 veces más y fueron más fecundas que las TR (p&lt;0.01). Las tilapias grandes tuvieron 1.6 veces menos desoves (p&lt;0.05) y produjeron menos huevos por cada 100 hembras que las pequeñas (p&lt;0.01). En general, la relación H:M no afectó las variables reproductivas. Las hembras pequeñas de ambas variedades tuvieron un mayor número de desoves que las grandes, y las tilapias CH grandes desovaron 3.9 veces más que las TR del mismo tamaño (p&lt;0.01), mientras que en las pequeñas esta diferencia fue de tan solo 1.7 veces (p&lt;0.05). Las tilapias CH grandes fueron reproductivamente más eficientes que las hembras de la misma categoría de la variedad TR. En conclusión, las tilapias CH y las hembras de menor talla y peso fueron reproductivamente más eficientes que las de la variedad TR y las de mayor tamaño. Independientemente de la variedad, la actividad reproductiva no se vio afectada por las proporciones entre hembras y machos

Frequency of cancer in children residing in Mexico City and treated in the hospitals of the Instituto Mexicano del Seguro Social (1996–2001)

BACKGROUND: The objective of this article is to present the frequency of cancer in Mexican children who were treated in the hospitals of the Instituto Mexicano del Seguro Social in Mexico City (IMSS-MC) in the period 1996–2001. METHODS: The Registry of Cancer in Children, started in 1996 in the IMSS-MC, is an on-going, prospective register. The data from 1996 through 2001 were analyzed and the different types of cancer were grouped according to the International Classification for Cancer in Children (ICCC). From this analysis, the general and specific frequencies by age and by sex were obtained for the different groups of neoplasms. Also, the frequency of the stage of the disease that had been diagnosed in cases of children with solid tumors was obtained. RESULTS: A total of 1,702 new cases of children with cancer were registered, with the male/female ratio at 1.1/1. Leukemias had the highest frequency with 784 cases (46.1%) and, of these, acute lymphoblastic leukemias were the most prevalent with 614 cases (78.3%). Thereafter, in descending order of frequency, were tumors of the central nervous system (CNST) with 197 cases (11.6%), lymphomas with 194 cases (11.4%), germinal cell tumors with 110 cases (6.5%), and bone tumors with 97 cases (5.7%). The highest frequency of cancer was found in the group of one to four year-olds that had 627 cases (36.8%). In all the age groups, leukemias were the most frequent. In the present work, the frequency of Hodgkin's disease (~4%) was found to be lower than that (~10%) in previous studies and the frequency of tumors of the sympathetic nervous system was low (2.3%). Of those cases of solid tumors for which the stage of the disease had been determined, 66.9% were diagnosed as being Stage III or IV. CONCLUSIONS: The principal cancers in the children treated in the IMSS-MC were leukemias, CNST, and lymphomas, consistent with those reported by developed countries. A 2.5-fold reduction in the frequency of Hodgkin's disease was found. Of the children, the stage of whose disease had been determined, two thirds were diagnosed as having advanced stages of the disease

XVI International Congress of Control Electronics and Telecommunications: "Techno-scientific considerations for a post-pandemic world intensive in knowledge, innovation and sustainable local development"

Este título, sugestivo por los impactos durante la situación de la Covid 19 en el mundo, y que en Colombia lastimosamente han sido muy críticos, permiten asumir la obligada superación de tensiones sociales, políticas, y económicas; pero sobre todo científicas y tecnológicas. Inicialmente, esto supone la existencia de una capacidad de la sociedad colombiana por recuperar su estado inicial después de que haya cesado la perturbación a la que fue sometida por la catastrófica pandemia, y superar ese anterior estado de cosas ya que se encontraban -y aún se encuentran- muchos problemas locales mal resueltos, medianamente resueltos, y muchos sin resolver: es decir, habrá que rediseñar y fortalecer una probada resiliencia social existente - producto del prolongado conflicto social colombiano superado parcialmente por un proceso de paz exitoso - desde la tecnociencia local; como lo indicaba Markus Brunnermeier - economista alemán y catedrático de economía de la Universidad de Princeton- en su libro The Resilient Society…La cuestión no es preveerlo todo sino poder reaccionar…aprender a recuperarse rápido.This title, suggestive of the impacts during the Covid 19 situation in the world, and which have unfortunately been very critical in Colombia, allows us to assume the obligatory overcoming of social, political, and economic tensions; but above all scientific and technological. Initially, this supposes the existence of a capacity of Colombian society to recover its initial state after the disturbance to which it was subjected by the catastrophic pandemic has ceased, and to overcome that previous state of affairs since it was found -and still is find - many local problems poorly resolved, moderately resolved, and many unresolved: that is, an existing social resilience test will have to be redesigned and strengthened - product of the prolonged Colombian social conflict partially overcome by a successful peace process - from local technoscience; As Markus Brunnermeier - German economist and professor of economics at Princeton University - indicates in his book The Resilient Society...The question is not to foresee everything but to be able to react...learn to recover quickly.Bogot

Characterization of a manganese ore to define the use in the fluxes synthesis for submerged arc welding

9 páginas, 3 figuras, 10 tablas.[ES] Se realiza la caracterización química, el análisis térmico diferencial y termogravimétrico (ATD y TG), la determinación de las fases por difractóme tría de rayos-X y el análisis granulométrico del mineral de manganeso del yacimiento "Margarita de Cambute", en Cuba. Sobre la base de los resultados de caracterización, se establece un plan de síntesis del fundente consistente en definir como condición básica el rango de valores de la relación MnO/Si02. La estrategia planteada se corrobora experimentalmente, mediante la obtención de un prototipo de fundente en homo eléctrico del arco acoplado a una fuente de corriente continua y la realización de ensayos del fundente en la soldadura.[EN] Chemical analysis, thermal analysis (DTA and TG), phase determination by X-ray diffraction and granulometric analysis of the manganese ore from the location "Margarita de Cambute" in the eastern part of Cuba were carried out. Based on these characterization results, a flux synthesis strategy was established, comprising the definition, as a basic condition, of the MnO/Si02 range of values. This strategy was confirmed experimentally by obtaining a flux prototype in an electric arc furnace connected to direct current source and the carrying out of the flux in submerged arc welding tests.Peer reviewe