Nucleon scattering on actinides using a dispersive optical model with extended couplings

Tamura coupling model has been extended to consider the coupling of additional low-lying rotational bands to the ground state band. Rotational bands are built on vibrational bandheads (even-even targets) or single particle bandheads (odd-$A$ targets) including both axial and non-axial deformations. These additional excitations are introduced as a perturbation to the underlying axially-symmetric rigid rotor structure of the ground state rotational band. Coupling matrix elements of the generalized optical model are derived for extended multi-band transitions in even-even and odd-$A$ nuclei. Isospin symmetric formulation of the optical model is employed. A coupled-channels optical model potential (OMP) containing a dispersive contribution is used to fit simultaneously all available optical experimental databases including neutron strength functions for nucleon scattering on $^{232}$Th, $^{233,235,238}$U and $^{239}$Pu nuclei and quasi-elastic ($p$,$n$) scattering data on $^{232}$Th and $^{238}$U. Lane consistent OMP is derived for all actinides if corresponding multi-band coupling schemes are defined. Calculations using the derived OMP potential reproduce measured total cross-section differences between several actinide pairs within experimental uncertainty for incident neutron energies from 50 keV up to 150MeV. Multi-band coupling is stronger in even-even targets due to the collective nature of the coupling; the impact of extended coupling on predicted compound-nucleus formation cross section reaches 5% below 3 MeV of incident neutron energy. Coupling of ground-state rotational band levels in odd-$A$ nuclei is sufficient for a good description of the compound-nucleus formation cross sections as long as the coupling is saturated (a minimum of 7 coupled levels are typically needed).Comment: 30 pages, 4 figures, 8 tables, 3 appendice

Predicting the optical observables for nucleon scattering on even-even actinides

Previously derived Lane consistent dispersive coupled-channel optical model for nucleon scattering on $^{232}$Th and $^{238}$U nuclei is extended to describe scattering on even-even actinides with $Z=$90--98. A soft-rotator-model (SRM) description of the low-lying nuclear structure is used, where SRM Hamiltonian parameters are adjusted to the observed collective levels of the target nucleus. SRM nuclear wave functions (mixed in $K$ quantum number) have been used to calculate coupling matrix elements of the generalized optical model. The "effective" deformations that define inter-band couplings are derived from SRM Hamiltonian parameters. Conservation of nuclear volume is enforced by introducing a dynamic monopolar term to the deformed potential leading to additional couplings between rotational bands. Fitted static deformation parameters are in very good agreement with those derived by Wang and collaborators using the Weizs\"acker-Skyrme global mass model (WS4), allowing to use the latter to predict cross section for nuclei without experimental data. A good description of scarce "optical" experimental database is achieved. SRM couplings and volume conservation allow a precise calculation of the compound-nucleus formation cross sections, which is significantly different from the one calculated with rigid-rotor potentials coupling the ground-state rotational band. Derived parameters can be used to describe both neutron and proton induced reactions.Comment: 6 pages, 4 figures, 5 table

Reproductive performance of a crossbreed of Cuban Creole boar with Duroc-Hampshire females

We describe in this paper the reproductive performance of Cuban Creole x (Duroc x Hampshire) cross-breed pigs. This cross-breeding system is presently under investigation for the reproductive improvement of mountain areas. Ours results have shown as these cross-breed population maintain good levels in the relation partution/fertilisation (82.74 percent) with respect to the employed pure breeds exploited in the same conditions. Litter size, birth weight, number of weaned, piglets and weaning weight were similar to the means reached by the exotic breeds, while the birth weight and the mean weaning weight were lower. In a general way, this crossbreeding can be considered as improver in Cuban mountain areas, pointing out the use of native genetic resources in its production.En este trabajo se describe el comportamiento reproductivo del cruzamiento entre cerdos Criollos Cubanos como línea paterna y hembras cruzadas Duroc x Hampshire. Esta pauta se encuentra en fase de investigación en Cuba para la mejora productiva de las áreas de montaña. Nuestros resultados han encontrado como este cruce se mantiene en unos niveles (82,74 p.100) para la relación parto/cubriciones frente a las razas puras intensamente explotadas en el mismo medio. El tamaño de la camada, el peso al nacimiento, el número de crías destetadas y el peso al destete, fueron similares a las medias de las razas exóticas, mientras que el peso al nacimiento y el peso promedio al destete fueron inferiores. En general este cruce puede considerarse mejorante para las condiciones de montaña, destacando la utilización de recursos genéticos autóctonos en su producción

Extern characterisation of iberian pig varieties based in cualitative variables

We are presenting a study of the external charcaterization of nine varieties of the Iberian pig based on seven cualitative external characteritics. We have used a sample of 566 adult individuals (515 females and 51 males) belonging to 28 different farm of the Iberian Pig Breed. The results of the non parametric ANOVA, the canonical discriminant analysis and Mahalanobis distancing have confirmed a clear differentiation among varieties, resulting the Torbiscal and Manchado de Jabugo varieties as the most distanced.Se realiza un estudio de caracterización exteriorista de las distintas variedades del cerdo Ibérico utilizando una muestra formada por un total de 566 individuos (515 hembras y 51 machos) pertenecientes a nueve variedades de la raza Ibérica. Para ello se analizan un total de siete variables cualitativas. Tanto los resultados del análisis de la varianza no paramétrico, el análisis discriminante canónico, como las distancias de Mahanalobis, nos confirman una clara diferenciación de todas las variedades de la raza basada en dichas variables, quedando el Torbiscal y el Manchado de Jabugo como las variedades más destacadas

Origin, evolution and present status in Spanish Alano dog

There exist several hypothesis about the origin of the Spanish Alano dog breed, but the most solid is the procedure from central Europe around the Vth century and another that locate their origin in the arrival of the Phoenicians to Spain in older times. Possibly, Alano was the most important Spanish breed from the mid-age to the end of the XIXth century, when they were used as a fighting dog, hunter dog and cattleherd dog. In the XXth century his breed was near the extinction. Presently a programme of recuperation and conservation is under development.Existen varias hipótesis sobre el origen del Alano Español aunque parece ser más sólida una que le atribuye una procedencia centroeuropea sobre el siglo V y otra más antigua con la llegada del pueblo fenicio a España. Posiblemente, el Alano fuese la raza española más importante desde la Edad Media hasta finales del siglo XIX, siendo utilizado como perro de combate, perro de caza y perro de ganado. En el siglo XX esta raza llegó casi a desaparecer encontrándose en la actualidad inmersa en un programa de recuperación y conservación

The Black Creole Cuban Pig: origin, evolution and present status

The origin of the Cuban Creole Black pig is under a controversy, but the majority of authors locate their procedure in the ancient Spanish Iberian branches. Others hypothesis point out a possible influence of pre-hispanic Black Canarian pig, and also the early influence of Duroc and Hampshire breeds. Coinciding with all the Cuban farming development, this breed increase greatly their census from the beginning of the colonisation to the first half of the XVIIIth century, when their decreasing started as a consequence of the big expansion of tobacco and sugar Cain agriculture. In the present century this breed was in risk of extinction because the competence of improved foreign breeds, but presently this bred has gain god perspectives, because her role in the Cuban sustainable development.El origen del Cerdo Negro Criollo Cubano sigue siendo discutido, aunque la mayoría de los autores atribuyen su procedencia de los antiguos troncos ibéricos de España. Otras hipótesis plantean una posible influencia de los cerdos canarios prehispánicos e incluso el aporte reciente de sangre de las razas Duroc y Hampshire. Esta raza, coincidiendo con todo el desarrollo ganadero cubano, incrementó enormemente sus censos desde el inicio de la colonización hasta la primera mitad del siglo XVIII donde comenzó su declive a consecuencia de la gran expansión de la explotación tabacalera y de la caña de azúcar. En el presente siglo ha peligrado su conservación por la competencia de las razas selectas extranjeras aunque en la actualidad presenta unas excelentes perspectivas de recuperación dentro del desarrollo sostenible de Cuba

Cuban creole pig in Bayamo jurisdiction

The former jurisdiction of Bayamo, as political colonial division began its way in the century XVI, after its foundation in 1513 as the second Cuban village. Currently the Bayamo village is integrated by 15 local districts, an extension of 835.12 km2 and a population 68690 inhabitants. In spite of have elapsed more than 470 years from the arrival of the first pigs from Spain, this region has maintained 6176 breeders of this native pig breed as direct descendant of the Mediterranean pigs. In this work is presented the racial, ecological and human factors, that they have permitted the maintenance of this population with origin in the Iberian pig.La antigua jurisdicción de Bayamo, como división política de la colonia comenzó su andadura en el siglo XVI, tras su fundación en 1513 como la segunda villa de Cuba. Actualmente el municipio de Bayamo lo integran 15 consejos populares, una superficie de 835,12 km2 y una población de 68690 habitantes. A pesar de haber transcurrido más de 470 años desde la llegada de los primeros cerdos desde España, esta región ha mantenido 6176 reproductores de la raza cerdo Criollo como descendiente directo de los cerdos mediterráneos. En este trabajo se presenta los factores racial, ecológico y humano, que han permitido la perdurabilidad de esta raza descendiente del cerdo Ibérico

Morphometric study in black varieties of Iberian pig breed

We are presenting a morphological study of the black varieties of the Iberian pig breed considering the Lampiño, Entrepelado, Mamellado, Silvela and Mamellado x Silvela strains, according to the Association of Breeders (AECERIBER) criteria. From the quantitative variables study, few significative differences among strains and sexes has been found, with absence of interactions between both factors. Also a posteriori homogeneity among means has been found significative association between strains and the frequencies of the coat colour, the types of hair, the hear type and the complementary particularities in the females, while in males a total independence have been shown.Se presenta un estudio morfológico en las variedades negras del cerdo Ibérico considerándose como tales las estirpes Lampiña, Entrepelado, Mamellado, Silvela y Mamellado x Silvela, según los criterios de catalogación de la asociación de criadores AECERIBER. En el estudio de las variables cuantitativas se deducen escasas diferencias entre estirpes y entre sexos y ausencia de interacciones entre ambos factores. Asimismo se encuentra una gran homogeneidad entre estirpes en el estudio de comparación de medias. Para las variables cualitativas se encuentra asociación significativa entre estirpes y el color de la capa, el tipo de orejas, el tipo de pelo y las particularidades para la muestra de hembras mientras que en los machos hay independencia entre las estirpes y las variables estudiadas