Classification of fold/hom and fold/Hopf spike-adding phenomena

The Hindmarsh-Rose neural model is widely accepted as an important prototype for fold/hom and fold/Hopf burstings. In this paper, we are interested in the mechanisms for the production of extra spikes in a burst, and we show the whole parametric panorama in an unified way. In the fold/hom case, two types are distinguished: a continuous one, where the bursting periodic orbit goes through bifurcations but persists along the whole process and a discontinuous one, where the transition is abrupt and happens after a sequence of chaotic events. In the former case, we speak about canard-induced spike-adding and in the second one, about chaos-induced spike-adding. For fold/Hopf bursting, a single (and continuous) mechanism is distinguished. Separately, all these mechanisms are presented, to some extent, in the literature. However, our full perspective allows us to construct a spike-adding map and, more significantly, to understand the dynamics exhibited when borders are crossed, that is, transitions between types of processes, a crucial point not previously studied. © 2021 Author(s)

La asignatura de Informática Aplicada a la Gestión de Empresas en Diplomatura en Ciencias Empresariales

El presente trabajo pretende mostrar no el programa de la asignatura de Informática Aplicada dentro de los estudios de Diplomatura en Ciencias Empresariales, sino de explicar cómo se imparte este programa y las conclusiones sacadas una vez terminado el período docente de la misma, siempre analizando las conclusiones tanto positivas como negativas. Simplemente mostramos el programa para cumplimentar el artículo

A theoretical insight into the photophysics of psoralen

Psoralen photophysics has been studied on quantum chemistry grounds using the multiconfigurational second-order perturbation method CASPT2. Absorption and emission spectra of the system have been rationalized by computing the energies and properties of the low-lying singlet and triplet excited states. The S1 ππ* state has been determined to be responsible of the lowest absorption and fluorescence bands and to initially carry the population in the photophysical processes related to the phototherapeutic properties of psoralen derivatives. The low-lying T1 ππ* state is, on the other hand, protagonist of the phosphorescence, and its prevalent role in the reactivity of psoralen is suggested to be related to the elongation of the pyrone ring C3–C4 bond, where the spin density is distributed on both carbon atoms. Analysis of energy gaps and spin-orbit coupling elements indicates that the efficient photophysical process leading to the population of the lowest triplet state does not take place at the Franck-Condon region but along the S1 relaxation [email protected] [email protected] [email protected]

El derecho político de la Segunda República

Estudio preliminar, edición y notas de Sebastián MartínVolumen en el que se editan (dos de ellas por vez primera) las memorias de cátedra de los tres principales constitucionalistas de la II República: Nicolás Pérez Serrano, Eduardo L. Llorens y Francisco Ayala. A través de dichos textos, convenientemente aclarados y ampliados por las notas del editor, los lectores pueden conocer los debates fundamentales que conformaban la disciplina del derecho político en el tiempo de entreguerras. Las memorias van precedidas por un exhaustivo estudio preliminar (pp. IX-CLXXXIX) sobre la fisonomía de aquel saber jurídico. En él se examinan la trayectoria de los profesores que impartían la asignatura; las instituciones en que se investigaba; las revistas, monografías, tratados y artículos en que circulaba; las controversias que la atravesaban; la mentalidad jurídica que de todo ello puede extraerse; y la singular aportación científica de Ayala, Llorens y Pérez Serrano, cuya obra, a juicio del prof. Martín, constituye el destilado más genuino del derecho político de la Segunda República.Este trabajo recibió una ayuda a la investigación de la Fundación Francisco Ayala y el Ministerio de Cultura. Ha sido elaborado en el marco de los proyectos de investigación DER2008-03069 y DER2010-21728-C02-0

Caracterización morfoagronómica de seis cultivares de ayote (Cucurbita moschata Duch.) e incidencia de artrópodos y enfermedades

ResumenCon el objetivo de llevar a cabo la caracterización morfoagronómica en seis cultivares de ayote  Cucurbita moschata Duch) se realizó la presente investigación durante los meses de Julio del 2016 hasta Abril del 2017, en la Estación Experimental y Prácticas de la Facultad de Ciencias agronómicas, Universidad de El Salvador, ubicado en el municipio de San Luis Talpa, departamento de La Paz. El Salvador, C.A.  Para los seis tratamientos representados como cultivares e identificados por la forma del fruto, se registraron características cuantitativas y cualitativas de 10 plantas por cultivar bajo la técnica del microtunel durante las primeras dos semanas. Los datos de las variables se obtuvieron por medio de la guía de descriptores según las normas Internacionales del IBPGR, interpretando los datos con el programa InfoStat 20.0 aplicando estadística descriptiva: promedios, desviación estándar, coeficiente de variación y análisis multivariado que comprende: Correlación, Componentes Principales y Conglomerados.  El análisis de conglomerados generado dividió en tres grupos o clúster los cultivares, cuyas características reflejan homogeneidad dentro de cada uno. Se concluye que al realizar la caracterización mostró relevantes diferencias en cuanto al rendimiento y el desarrollo de la planta, observando el potencial de cada cultivar para diferentes propósitos de acuerdo a sus características. En el registro de artrópodos asociados al ayote los organismos que ocasionaron mayores daños son: Coleóptera: Crhysomelidae, incluyendo los géneros Diabrótica sp. y Acalymma sp; Lepidoptera: Pyralidae: Diaphania sp., y Sesiidae: Melittia sp. Asimismo, se identificaron los organismos de rol benéfico: Apidae (Apis sp., y Melipona sp.); Vespidae: Polybia sp.; Hemíptero: Anthocoridae: Orius sp., y Neuróptera: Chrysopidae. La manifestación de síntomas por virus y hongos se identificó en laboratorio por parte del CENTA, determinando la presencia de Cercospora sp., Curvularia sp., Alternaria sp., Sclerotium sp., y en mayor cantidad de daño el patógeno Pseudoperonospora sp.AbstractIn order to carry out the morphoagronomic characterization in six cultivars of cucumber (Cucurbita moschata Duch), this research was carried out during the months of July 2016 to April 2017, at the Experimental Station and Practices of the Faculty of Agronomic Sciences, University Of El Salvador, located in the municipality of San Luis Talpa, Department of La Paz. El Salvador, C.A. For the six treatments represented as cultivars and identified by the fruit shape, quantitative and qualitative characteristics of 10 plants per cultivar were recorded, and under the microtunel technique during the first two weeks. The data of the variables were obtained through the descriptive guide according to IBPGR International standards, interpreting the data with the program InfoStat 20.0 applying descriptive statistics: averages, standard deviation, coefficient of variation and multivariate analysis that includes: Correlation, Components Main and Conglomerates. The conglomerates generated by the multivariate analysis were divided into three groups whose characteristics reflect homogeneity within each one. It is concluded that the characterization showed significant differences in the yield and development of the plant, observing the potential of each cultivar for different purposes according to their characteristics. In the register of arthropods associated with the crop, the organisms that caused the most damage are: Coleoptera: Crhysomelidae, including the genus Diabrótica sp. and Acalymma sp, Lepidoptera: Pyralidae: Diaphania sp., And Sesiidae: Melittia sp. Likewise, organisms with a beneficial role were identified: Apidae (Apis sp., and Melipona sp.), Vespidae: Polybia sp., Hemiptera: Anthocoridae: Orius sp., and Neuróptera: Chrysopidae. The manifestation of symptoms by viruses and fungi was identified in the laboratory by CENTA, determining the presence of Cercospora sp., Curvularia sp., Alternaria sp., Sclerotium sp., and in greater amount of damage the pathogen Pseudoperonospora sp

Fibrinogen-Derived γ377-395 Peptide Improves Cognitive Performance and Reduces Amyloid-β Deposition, without Altering Inflammation, in AβPP/PS1 Mice

Fibrinogen has emerged as a promising therapeutic target against Alzheimer's disease because of its dual role in altered vascular function and amyloid-β aggregation. Here we provide evidence regarding cognitive improvement and reduction of brain parenchyma amyloid-β deposition in AβPP/PS1 mice after treatment for one month with the fibrinogen-blocking peptide Fibγ377-395. No alteration in glial response or other neuroinflammatory markers was observed in the cortex of treated animals. Considering these results and the fact that Fibγ377-395 does not affect coagulation function, this peptide could be considered as a promising and safe candidate for chronic treatment of Alzheimer's disease

Una herramienta de apoyo para la enseñanza de informática en estudios empresariales

En este artículo se presenta una experiencia llevada a cabo en la Facultad de Ciencias Económicas y Empresariales de Badajoz. Esta se centra en la metodología utilizada para la realización, impartición y seguimiento de las prácticas de las asignaturas de informática que existen en dicho Centro, si bien esta metodología se puede poner en práctica en cualquier asignatura de informática de cualquier titulación. Con ese objetivo se han adaptado las características de un software de administración remota de libre distribución, comentando las ventajas e inconvenientes que hemos encontrado para el desarrollo de una clase interactiva. Por una parte desde el punto de vista de rendimiento de la computadora, y por otra parte, las ventajas e inconvenientes que tiene para los alumnos el seguimiento de la clase de prácticas utilizando esta metodología

A survey for gregarines (Protozoa: Apicomplexa) in arthropods in Spain

Gregarines thrive in the digestive tract of arthropods and may be deleterious to their hosts, especially when present in high densities. The impact of parasites on these invertebrates may affect both the ecosystem equilibrium and human economic activities. However, information available on gregarines in Spain is limited. Therefore, a microscopic study on prevalence of gregarine infection in 560 insects and crustaceans was undertaken in Madrid and Tarragona. Gregarina ormierei (78% prevalence), Stylocephalus gigas (56 %), Oocephalus hispanus (13 %) and Actinocephalus permagnus (only one infected out of six beetles examined) were found in coleopteran hosts. Gregarina ovata and G. chelidurellae showed moderate frequency of infection (35 %) in dermapterans. An undescribed Gregarina sp. (76 % prevalence) was observed for the first time in freshwater decapod crustaceans. Interestingly, G. ormierei showed a noticeable phenotypic dimorphism, which justifies its redescription based on modern taxonomic criteria. Sequences of the 18S rRNA gene could be obtained only in the presence of highly prevalent gregarines. G. ormierei and Gregarina sp. were related (85 and 94 % identity by BLASTN, respectively) to G. basiconstrictonea and G. cloptoni, respectively, whereas S. gigas was closely related to both Xiphocephalus ellisi and S. giganteus (> 97 % identity). Phylogenetic trees based on ribosomal sequences unequivocally grouped these new isolates either with the Gregarinidae (G. ormierei and Gregarina sp.) or the Stylocephalidae (S. gigas)

Revealing hidden clonal complexity in Mycobacterium tuberculosis infection by qualitative and quantitative improvement of sampling

AbstractThe analysis of microevolution events, its functional relevance and impact on molecular epidemiology strategies, constitutes one of the most challenging aspects of the study of clonal complexity in infection by Mycobacterium tuberculosis. In this study, we retrospectively evaluated whether two improved sampling schemes could provide access to the clonal complexity that is undetected by the current standards (analysis of one isolate from one sputum). We evaluated in 48 patients the analysis by mycobacterial interspersed repetitive unit–variable number tandem repeat of M. tuberculosis isolates cultured from bronchial aspirate (BAS) or bronchoalveolar lavage (BAL) and, in another 16 cases, the analysis of a higher number of isolates from independent sputum samples. Analysis of the isolates from BAS/BAL specimens revealed clonal complexity in a very high proportion of cases (5/48); in most of these cases, complexity was not detected when the isolates from sputum samples were analysed. Systematic analysis of isolates from multiple sputum samples also improved the detection of clonal complexity. We found coexisting clonal variants in two of 16 cases that would have gone undetected in the analysis of the isolate from a single sputum specimen. Our results suggest that analysis of isolates from BAS/BAL specimens is highly efficient for recording the true clonal composition of M. tuberculosis in the lungs. When these samples are not available, we recommend increasing the number of isolates from independent sputum specimens, because they might not harbour the same pool of bacteria. Our data suggest that the degree of clonal complexity in tuberculosis has been underestimated because of the deficiencies inherent in a simplified procedure