Functional analysis of a homolog of the pair-rule gene hairy in the short-germ beetle Tribolium castaneum

Drosophila melanogaster is by far the best-understood model for 'long germ' developing insects. The most remarkable feature of its development is the specification of all segments during the syncitial blastoderm stage by a mechanism that relies on free diffusion of maternally provided and zygotic transcription factors between the uncellularized nuclei of the early blastoderm. In contrast to this, most insects undergo a short germ development, where only few anterior segments are specified at this stage. Although the ontogeny of several insects from different orders has been analysed so far, it still remains unclear if the principles discovered in Drosophila also apply for the generation of the post-blastoderm derived segments of short germ insects, and how this system might have evolved. The functional analysis of the Tribolium castaneum hairy homolog by pRNAi provided in this thesis and the analysis of the knock down embryos by in situ hybridization using different molecular markers, strongly indicates that Tc'h functions as a pair-rule gene during the segmentation of blastoderm derived segments and suggests a conservation of this function between Tribolium and Drosophila. In contrast to this no such role could be observed for segments specified during the elongation process of the Tribolium germ-band. Interestingly, this function appears to be masked by an additional function of Tc'h in the further development of the embryonic head, which causes the loss of all segments anterior to the third thoracic segment and may indicate the presence of an anterior organizer which governs the proper maturation of this region during development. Analysis of the regulation of Tc'h, in comparison to its Drosophila homolog, shows that the regulatory cascade governing its expression differs substantially between these species. Whereas the Tribolium gap gene orthologs Tc'Kr and likely also Tc'hb do not seem to participate in the regulation of the Tribolium hairy pair-rule pattern in a similar way as in Drosophila, a strong regulatory influence of Tc'gt could be observed in these experiments, reminiscent of the situation in Drosophila. Analysis of the regulatory target gene Tc'ftz indicates that the regulatory interaction between these genes might be conserved, although the function of this interaction differs substantially between Drosophila and Tribolium. Despite the differences found in the regulation of the hairy gene in Tribolium and Drosophila, a trans-species experiment using a lacZ reporter construct under the control of a Tribolium hairy enhancer, specifically regulating the expression of three central stripes #3-#5 in Tribolium, does indeed show expression of the corresponding stripes in transgenic Drosophila lines. Furthermore, crosses of these lines with Drosophila gap and pair-rule gene mutants strongly suggest a participation of these genes in the regulation of the observed pattern. Intriguingly, complementary experiments performed in Tribolium, using similar constructs harbouring stripe specific elements for the stripes #3-#4 from Drosophila, also exhibit stripe like expression at comparable positions in the Tribolium germ-band. However, pRNAi experiments performed with the Tribolium gap genes Tc'hb and Tc'Kr suggest a different regulation for the generation of these stripes. The results obtained in this study reveal part of the regulation and function of the Tribolium castaneum hairy homolog and allow interesting speculations on the molecular events that may allow the transition from short- to long-germ development and the evolution of pair-rule patterning in higher insect

Suitable task allocation in intelligent systems for assistive environments

The growing need of technological assistance to provide support to people with special needs demands for systems more and more efficient and with better performances. With this aim, this work tries to advance in a multirobot platform that allows the coordinated control of different agents and other elements in the environment to achieve an autonomous behavior based on the user’s needs or will. Therefore, this environment is structured according to the potentiality of each agent and elements of this environment and of the dynamic context, to generate the adequate actuation plans and the coordination of their execution.Peer ReviewedPostprint (author's final draft

Propagation of generalized vector Helmholtz-Gauss beams through paraxial optical systems

We introduce the generalized vector Helmholtz-Gauss (gVHzG) beams that constitute a general family of localized beam solutions of the Maxwell equations in the paraxial domain. The propagation of the electromagnetic components through axisymmetric ABCD optical systems is expressed elegantly in a coordinate-free and closed-form expression that is fully characterized by the transformation of two independent complex beam parameters. The transverse mathematical structure of the gVHzG beams is form-invariant under paraxial transformations. Any paraxial beam with the same waist size and transverse spatial frequency can be expressed as a superposition of gVHzG beams with the appropriate weight factors. This formalism can be straightforwardly applied to propagate vector Bessel-Gauss, Mathieu-Gauss, and Parabolic-Gauss beams, among others

Function of antioxidant enzymes and metabolites during maturation of pea fruits

Panel (S2-P29) presentado en la Reunión de la Sociedad Española de Fisiología Vegetal (SEFV) (18ª. Zaragoza. 8-11 septiembre 2009).Leguminous plants such as pea (Fisum sativum), bean (Fhaseolus vulgaris) or alfalfa (Medicago sativa) are crops of major economical value as protein source for human and animal consumption. They are also essential to sustainable agricultural systems because of their ability to establish nitrogen-fixing symbioses with soil bacteria, thus providing a biological alternative to chemical fertilization. The concentration of antioxidants in fruits is important agronomically, as it is well documented that antioxidants may protect fruit tissues from potentially toxic reactive oxygen species (ROS) and thus contribute to the stress tolerance of crops. Furthermore, following harvest, fruits have a relatively short shelf-life during which they undergo changes in texture, colour and flavour. Because ROS may be involved in the oxidative processes contributing to fruit deterioration, the antioxidant content is important in terms of both the nutritional value and the post-harvest storage of the fruits. Although the antioxidants are believed to play a crucial role in the ripening process of climacteric fruits, their role in the development, maturation and post-harvest storage of legume fruits is poorly defined. We determined the antioxidant capacity (ascorbate-glutathione pathway, superoxide dismutases, catalases, glutathione peroxidases and peroxiredoxins) of mature fruits from nodulated plants and from plants supplied with combined nitrogen, and concluded that pea fruits from plants dependent on nitrogen fixation show similar antioxidant levels to those dependent on chemical fertilization. Furthermore, oir results showed that fruit maturation causes a decline in the antioxidants of pea fruits. However, the concentration of lipid peroxides and oxidized proteins remained unaltered, suggesting that, contrary to the situation described in climacteric fruits, a decrease in the antioxidant capacity does not necessarily lead to oxidative stress in maturing pea fruits. Similarly, oir data showed that despite the decreases in several antioxidants, oxidative processes are probably not involved in legume fruit deterioration during storage at room temperature. Finally, our results underscore the importance of ascorbate, one of the key components of the antioxidant network, in pea fruit growth and development.This work was funded by Ministerio de Ciencia e Innovación (grant AGL2008-01298) and Gobierno de Aragón (PIP137/2005 and group A53).Peer reviewe

Population size estimate of Abronia lythrochila Smith & Álvarez del Toro, 1963 (Reptilia: Anguidae) in the Estación Biológica San José, Chiapas, Mexico

La lagartija arborícola Abronia lythrochila fue descrita hace unos 60 años; sin embargo, su historia natural sigue siendo poco investigada. El objetivo de este estudio fue estimar la densidad poblacional y la distribución espacial de A. lythrochila en el Centro para la Conservación e Investigación de la Biodiversidad de los Altos de Chiapas (CECIBACH, anteriormente conocido como Estación Biológica San José) en Chiapas, México. Con base en los datos de campo recopilados entre 2017 y 2019, la densidad de población fue de 1.7 individuos/hectárea, lo que se traduce en un tamaño poblacional estimado de 7─89 ejemplares en la totalidad de las 16 hectáreas del CECIBACH. Debido a las actividades humanas que amenazan los bosques de los Altos de Chiapas, junto con la percepción errónea de la especie como peligrosamente venenosa, esta población de A. lythrochila podría estar sufriendo un declive continuo. El presente estudio ofrece la primera línea de base para la demografía poblacional comparativa de esta especie.The arboreal lizard Abronia lythrochila was described about 60 years ago, yet its natural history remains poorly researched. The objective of this study was to estimate the population density and spatial distribution of A. lythrochila at the Centro para la Conservación e Investigación de la Biodiversidad de los Altos de Chiapas (CECIBACH, formerly known as the Estación Biológica San José) in Chiapas, Mexico. Based on field data collected from 2017─2019, the estimated population density was 1.7 individuals per hectare, representing an estimated population size between 7─89 specimens across the entire 16 hectares of CECIBACH. Due to human activities that threaten forests in the highlands of Chiapas, together with misperceptions of the species as dangerously venomous, this population of A. lythrochila could be suffering an ongoing decline. The current study offers the first-ever baseline for comparative population demography of this species

Violencia conyugal hacia la mujer en el Municipio de Mateare. junio-agosto 2004.

En este estudio se comprobó que la violencia intra familiar tiene efectos sociales, económicos y culturales, donde la falta de los mismos convierte a las mujeres en seres vulnerables, no solo a nivel individual sino también ante las instituciones pues quedo demostrado el gran subregistro en relación a las denuncias así como la clasificación de los tipos de violencia, ya que los datos que nos fueron suministrados institucionalmente minimizan el efecto y las secuelas encontradas al realizar las entrevistas en cuarenta mujeres que sufren de violencia intra familiar. A su vez encontramos que no esta definida a nivel municipal una ruta critica para las mujeres afectadas por violencia intra familiar y no existe comunicación inter institucional para el control y seguimiento de los casos, aunque todos los actores sociales del Municipio reconocen la violencia como un problema de salud pública en ninguna de las instituciones existe un plan de prevención, detección, atención y seguimiento de los casos. De este hecho consideramos necesario la elaboración de un Plan de Lucha Contra la Violencia que incluye acciones coordinadas, estratégicas e inter sectorialmente con la participación de gobierno Municipal como de la sociedad civil

Sediment transport and dispersal in the nearshore of “flash-flood” rivers

River sediment dispersal on the near-shore of “flash-flood” rivers is investigated using a coupled wave-current-sediment transport model. Besòs and Llobregat rivers (short and mountainous rivers in NW Mediterranean Sea, near to Barcelona City) are used as examples to study the sediment transport under “flash-flood” regime. The modeling system COWAST which includes the coupling between the water circulation model ROMS and the wave model SWAN, is applied to assess the sediment dispersal mechanisms and deposition in the coastal area off the two river mouths. Preferential depositional areas such as mud-belts were identified from the simulations. The sediment dispersal pattern obtained by the model agrees with observational measurments. Complementary numerical simulations revealed sorting of sediment grain size in the cross-shelf direction.Peer ReviewedPostprint (published version

Event-based control for sit-to-stand transition using a wearable exoskeleton

Sit-to-stand transition is an essential step in a lower limb rehabilitation therapy, mainly for assisting the patient to transit from wheel chair to the next level of therapy. A mixed stiffness-damping control adaptation is proposed for this task which will help in reaching the final position with a constant velocity. A combination of control model is proposed to ensure the initiation and the final stage of the transition, such as to ensure stability and to maintain the equilibrium. The combined control model helps in reaching the goal position with equal participation from the user. For patient studies, such as with paraplegic patients, a combinational control model with muscle stimulation can be included to provide a complete assistance. The role of muscle stimulation and joint movement assistance is also considered in this control model. Further, final stage of this transition must ensure keeping or helping the user to maintain the upright position.Peer ReviewedPostprint (author's final draft