162 research outputs found
Postnatal ontogeny of the femur in fossorial and semiaquatic water voles in the 3D-shape space
Altres ajuts: Acord transformatiu CRUE-CSICWater voles of the genus Arvicola constitute an excellent subject to investigate to which extent function affects postnatal developmental growth of limb structures in phylogenetically close species. We performed a comparative analysis of postweaning femur form changes between Arvicola sapidus (semiaquatic) and Arvicola scherman (fossorial) using three-dimensional landmark-based geometric morphometrics. In both species, we observed greater femur robustness in juvenile individuals than in adult ones, probably due to the accommodation of high loads on the bone during initial locomotor efforts. Significant interspecific differences were also found in the femur size and shape of adult specimens, as well as in the postnatal allometric and phenotypic trajectories. In terms of phenotypic variation, fossorial water voles show relatively wider third and lesser trochanters, and greater femur robustness than A. sapidus, characters associated to the digging activity. In contrast, A. sapidus displays a slight increase of the greater trochanter in comparison with A. scherman, which is seemingly an adaptive response for enhancing propulsion through the water. Results evidence that certain morphological traits and differences between A. sapidus and A. scherman in the allometric and phenotypic trajectories of the femur are associated with their different locomotor mode
Nuevos modelos docentes: del homo “tecnofóbico” al homo tecnológico. ¿Una selección natural o una evolución imposible?
[SPA] El Espacio Europeo de Enseñanza Superior implica un cambio en la metodología docente. Sin este cambio las universidades solo habrán conseguido implantar nuevos nombres a sus planes de estudio pero no un modelo de enseñanza. Las reticencias tecnológicas que existen aún en la sociedad se dan también en las universidades y, sobre todo, en los docentes. Los autores analizan esta realidad sociológica y se plantean si, en realidad, los nuevos cambios que se exigen son posibles, existiendo todavía cierta fobia tecnológica, o quedarán en un planteamiento utópico más. La forma de medir el rendimiento académico (ECTS, European Credit Transfer System) exige necesariamente una evolución conjunta y coordinada entre el docente y el alumnado. [ENG] The European Higher Education System involves a change in the educational methodology. Without this change universities only would have managed to introduce new names to their study plans but not an educational model. Technological reluctances existing in the society are also given in universities, especially, in the teaching staff. Authors analyse this sociological reality and consider whether the new demanded changes are possible in fact as it still exists certain technological phobia, or they will turn into one more utopian proposal. The way academic efficiency is measured, ECTS (European Credit Transfer System), demands necessarily a coordinated evolution of the teacher together with the student body
Variational modularity at the cell level : insights from the sperm head of the house mouse
Background: Modularity is an important feature in the evolvability of organisms, since it allows the occurrence of complex adaptations at every single level of biological systems. While at the cellular level the modular organization of molecular interactions has been analyzed in detail, the phenotypic modularity (or variational modularity) of cell shape remains unexplored. The mammalian spermatozoon constitutes one of the most complex and specialized cell types found in organisms. The structural heterogeneity found in the sperm head suggests an association between its inner composition, shape and specificity of function. However, little is known about the extent of the connections between these features. Taking advantage of the house mouse sperm morphology, we analyzed the variational modularity of the sperm head by testing several hypotheses related to its structural and functional organization. Because chromosomal rearrangements can affect the genotype-phenotype map of individuals and thus modify the patterns of covariation between traits, we also evaluate the effect of Robertsonian translocations on the modularity pattern of the sperm head. Results: The results indicated that the house mouse sperm head is divided into three variational modules (the acrosomal, post-acrosomal and ventral spur module), which correspond to the main regions of the cytoskeletal mesh beneath the plasma membrane, i.e., the perinuclear theca. Most of the covariation is concentrated between the ventral spur and the acrosomal and post-acrosomal modules. Although the Rb fusions did not alter the main modularity pattern, they did affect the percentages of covariation between pairs of modules. Conclusions: The structural heterogeneity of the cytoskeleton is responsible for the modular organization of the sperm head shape, corroborating the role that this structure has in maintaining the cell shape. The reduction in percentages of shape covariation between pairs of modules in Rb sperms suggests that chromosomal rearrangements could induce changes in the genotype-phenotype map. Nevertheless, how these variations affect sperm fertilization success is yet to be elucidated
Gestión institucional y clima organizacional de los docentes de una Institución Educativa Vinces, 2021
Como objetivo de investigación se tuvo en cuenta determinar la relación entre la
gestión institucional y clima organizacional de los docentes de una institución
educativa Vinces, 2021.
La metodología utilizada fue de diseño no experimental, con un nivel
correlacional, transversal, de enfoque cuantitativo, teniendo como técnica la
encuesta y el instrumento utilizado fue el cuestionario de gestión institucional y
clima organizacional, dirigido a docentes que conformaron una muestra de 40
docentes. Como resultados se demostró que si se relaciona el liderazgo directivo
Rho=0.473 y el valor de significancia (0.002); planificación estratégica Rho de
Spearman fue de 0.651 y su valor de significancia (0.000); evaluación de la
gestión y la capacitación del personal Rho=0.502 y el valor de significancia
(0.001) si se relacionan significativamente con el clima organizacional.
Concluyendo que sí existe una relación significativa entre la gestión institucional
y clima organizacional de los docentes de una institución educativa Vinces, 2021
Lo fantástico como indagación. La ficción como herramienta del conocimiento
Conferencia plenaria del Congreso Internacional Figuraciones de lo insólito en las literaturas española e hispanoamerican
Effect of chromosomal reorganizations on morphological covariation of the house mouse mandible: insights from a Robertsonian system of Mus musculus domesticus
Morphological integration and modularity depend on genetic covariation between traits, which emerges from pleiotropic effects of single loci and genetic linkage between loci. Since chromosomal reorganizations alter meiotic recombination, they might modify groups of linked genes and entail the fixation of new alleles with new pleiotropic effects. As a result, they could contribute to the intraspecific variation of the covariance structure of morphological traits. Although the mouse mandible has long been studied in terms of development and evolution, little is known about how its covariance structure varies in natural populations with chromosomal reorganizations. Consequently, here we analyzed the magnitude and patterns of morphological covariation of mandible shape in groups of mice with different karyotypes from a Robertsonian system of Mus musculus domesticus. Results: The organization of the mouse mandible into two main modules was confirmed in all chromosomal groups, since RV coefficients for the corresponding subdivision of landmarks were always significant. However, substantial variation in the magnitude of integration was detected between groups, especially when the effect of allometry was not removed. A significant positive correlation between differences in magnitude of integration of the symmetric component of shape and karyotypic distances between groups was detected when not correcting for size. Moreover, the degree of dependence of symmetric shape variation on size showed a negative association with the chromosome number and a positive association with the magnitude of integration. All groups showed similar patterns of morphological integration of the mandible, especially regarding the symmetric component of shape. However, the display of landmark displacements and the computation of vector angles highlighted some differences. In addition, distances between groups in terms of covariation matrices of the symmetric component were positively correlated with geographic distance. Conclusions: Robertsonian translocations do not alter the organization of the mouse mandible into two main modules, but do affect the magnitude of integration between them. This effect is mainly due to changes in the allometric relationship. In the 'Barcelona' Robertsonian system, geographically structured sources of variation seem to affect the patterns of integration by producing parallel variation in separate developmental pathways. Overall, our results suggest that Robertsonian translocations could play a role in intraspecific differentiation processes by producing changes in the covariance structure of morphological traits
Producción de biomasa de C. elegans a partir de residuos de levadura de la industria cervecera
Motivación: La revalorización de residuos es un asunto de creciente importancia, debido a la cada vez mayor rigidez en materia de normativas de sostenibilidad y medio ambiente. La industria cervecera produce grandes excedentes de levadura, cuya gestión es costosa, y su valoración como subproducto es inevitable (Ferreira,I.M.P.L.V.O. 2010). Por otro lado C. elegans ha demostrado ser un buen candidato para la elaboración de nuevos piensos sostenibles en acuicultura, un sector también en crecimiento exponencial a nivel mundial donde España no es una excepción al respecto. Por ser un organismo modelo, con su genoma secuenciado y del que cada día se conoce mejor su ecología y fisiología, con numerosos mutantes en rutas de interés como el metabolismo de lípidos, que llegan a ser el 30% de su peso seco, se abren nuevas líneas de mejora en calidad y sostenibilidad del aún joven sector de la acuicultura. Métodos: Hemos empleado levadura cervecera crecida en YPD para elaborar medios análogo al S-Medium, ideal para el crecimiento de C. elegans (Lewis y Fleming, 1995), a distintas concentraciones y diferentes tratamientos físicos. Utilizamos la estirpe silvestre N2, así como la CC1, insensible a la hormona de formación de larva dauer por quorum sensing. Por conteo diario y peso seco por extracción en gradiente de sacarosa hallamos el rendimiento de la conversión de biomasa de levadura en gusano (Portman,D.S. 2006). Resultados: Los resultados provisionales apuntan a una concentración óptima de 4,5% de levadura con un rendimiento cercano al 30% para la estirpe N2. Sin embargo la estirpe CC1 no alcanza ni de lejos esos valores, pese a los buenos resultados de trabajos anteriores con extracto de levadura y peptona (Gelabert,D. 2012). Los tratamientos físicos como la sonicación o la pasteurización aceleran el ritmo de crecimiento y conversión de biomasa, pero no lo incrementan significativamente.Conclusiones: A falta aún de experimentos más concluyentes, unos rendimientos del 30% son muy positivos, y mejoran con creces los resultados obtenidos en trabajos anteriores (Gelabert,D. 2012). Nuevas líneas de mejora podrían incluir el uso de mutantes obesos, así como la implementación del medio con elementos deficitarios. El paso siguiente es el escalado en reactor con el residuo completo y distintos tratamientos, y el análisis nutricional del preparado, que revelará el contenido proteico y la calidad de sus lípidos, elementos clave en la nutrición de alevines en acuicultura
Gestión empresarial y competitividad de las mypes del centro comercial Parque Lambramani, Arequipa 2022
La presente investigación cuyo objetivo fue determinar la relación entre la gestión
empresarial y competitividad, de las mypes del centro comercial Parque
Lambramani, Arequipa 2022.Así mismo la metodología de investigación empleada
se fundamenta en los siguientes puntos; el tipo de investigación es aplicada, nivel
de investigación es descriptiva correlacional, diseño es no experimental de corte
transversal. La población fue de 98 mypes, la muestra fue de 30 mypes y el
muestreo fue no probabilístico. Además, la técnica e instrumento aplicado para el
levantamiento de información son la encuesta y cuestionario de tipo Likert,
conformada por 20 preguntas. Por ende, fue validado en cuanto a su contenido por
especialistas profesionales según la carrera de forma ampliamente positiva y
siendo su nivel de confiabilidad de acuerdo al coeficiente Alfa Conbrach de 0,957,
el cual significa una excelente fiabilidad. Posteriormente las informaciones
recopiladas fueron analizadas mediante el programa estadístico SPSS
v.27.Finalmente, del procesamiento de toda la información pertinente, quedó
demostrado de acuerdo a los resultados obtenidos que existe una relación directa
entre el Gestión empresarial y la Competitividad; de correlación significativamente
positiva alta
On the Elimination of Infections Related to Oncogenic Human Papillomavirus: an Approach using a Computational Network Model
[EN] Cervical cancer is the fourth most common malignancy in women worldwide, although it is preventable with prophylactic HPV vaccination. HPV transmission-dynamic models can predict the potential for the global elimination of cervical cancer. The random network model is a new approach that allows individuals to be followed, and to implement a given vaccination policy according to their clinical records. We developed an HPV transmission-dynamic model on a lifetime sexual partners network based on individual contacts, also accounting for the sexual behavior of men who have sex with men (MSM). We analyzed the decline in the prevalence of HPV infection in a scenario of 75% and 90% coverage for both sexes. An important herd immunity effect for men and women was observed in the heterosexual network, even with 75% coverage. However, HPV infections are persistent in the MSM population, with sustained circulation of the virus among unvaccinated individuals. Coverage around 75% of both sexes would be necessary to eliminate HPV-related conditions in women within five decades. Nevertheless, the variation in the decline in infection in the long term between a vaccination coverage of 75% and 90% is relatively small, suggesting that reaching coverage of around 70-75% in the heterosexual network may be enough to confer high protection. Nevertheless, HPV elimination may be achieved if men's coverage is strictly controlled. This accurate representation of HPV transmission demonstrates the need to maintain high HPV vaccination coverage, especially in men, for whom the cost-effectiveness of vaccination is questioned.This work has been supported by the Spanish Ministerio de Economia, Industria y Competitividad (MINECO), the Agencia Estatal de Investigacion (AEI) and Fondo Europeo de Desarrollo Regional (FEDER UE), grant MTM2017-89664-P. Authors also wish to acknowledge Maria Giovanna Ferrario, Victor Latorre, and the Medical Statistics Consulting team (Valencia, Spain) for their collaboration in writing this manuscript.Muñoz-Quiles, C.; Diez-Domingo, J.; Acedo, L.; Sánchez-Alonso, V.; Villanueva Micó, RJ. (2021). On the Elimination of Infections Related to Oncogenic Human Papillomavirus: an Approach using a Computational Network Model. Viruses. 13(5):1-12. https://doi.org/10.3390/v13050906S11213
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