Hexagonal Tilings and Locally C6 Graphs

We give a complete classification of hexagonal tilings and locally C6 graphs, by showing that each of them has a natural embedding in the torus or in the Klein bottle. We also show that locally grid graphs are minors of hexagonal tilings (and by duality of locally C6 graphs) by contraction of a perfect matching and deletion of the resulting parallel edges, in a form suitable for the study of their Tutte uniqueness.Comment: 14 figure

Relationships between adolescent physical self-concept and physical activity

El objetivo de este estudio es someter a prueba dos modelos contrapuestos sobre las relaciones entre las autopercepciones físicas y la actividad físico-deportiva en la adolescencia: mientras que un modelo postula la influencia de la actividad física sobre el autoconcepto físico, el modelo alternativo propone al autoconcepto físico como factor influyente en la actividad físicodeportiva. Participan en la investigación 704 estudiantes, 394 (55.96 %) hombres y 310 (44.04 %) mujeres entre 11 y 19 años (M = 14.91; D.T. = 2.13), residentes en dos Comunidades Autónomas (Cantabria y País Vasco) de España. Los resultados indican que las influencias entre el autoconcepto físico y la actividad físico-deportiva se producen de forma bidireccional si bien ajusta mejor el modelo que propone al autoconcepto físico como factor influyente. Se comprueban diferencias entre hombres y mujeres en el modelo. Por otro lado, la autopercepción de atractivo físico mantiene una relación negativa con la actividad físico-deportivaThe aim of this study is to test two opposing models of the relationship between physical self-perceptions and physical activity during adolescence: one which postulates that physical activity influences physical self-concept, and another one which proposes that physical self-concept influences physical activity. Participants were 704 students aged between 11 and 19 (M = 14.91; SD = 2.13) from two different Autonomous Regions in Spain (Cantabria and the Basque Country). 394 (55.96%) were male and 310 (44.04%) were female. The results indicate that the influences between physical self-concept and physical activity are bidirectional in nature, although the model that proposes physical selfconcept as an influencing factor was found to have a better fitness. Differences were found in the model between male and female students. Furthermore, selfperception of physical attractiveness was found to be negatively related to physical activityEste artículo lo firman componentes del Grupo Consolidado de Investigación del Sistema Universitario Vasco IT701-13 y forman parte de los resultados del proyecto EDU2009-10102 (subprograma EDUC) subvencionado por el MICINN. La investigación se ha realizado con la colaboración del Programa para la Contratación de Doctores Recientes de la Universidad del País Vasco (UPV/EHU

A Postprocessing methodology for direct normal irradiance forecasting using cloud information and aerosol load forecasts

A method for direct normal irradiance (DNI) forecasting for specific sites is proposed. It is based on the combination of a numerical weather prediction (NWP) model, which provides cloud information, with radiative transfer simulations fed with external aerosol forecasts. The NWP model used is the ECMWF Integrated Forecast System, and the radiative transfer information has been obtained from the Library of Radiative Transfer (libRadtran). Two types of aerosol forecasts have been tested: the global Monitoring Atmospheric Composition and Climate (MACC) model, which predicts five major components of aerosols, and the Dust Regional Atmospheric Model (BSC-DREAM8b) added to a fixed background calculated as the 20th percentile of the monthly mean of AERONET 2.0 observations from a different year. The methodology employed is valid for all meteorological situations, providing a stable and continuous DNI curve. The performance of the combined method has been evaluated against DNI observations and compared with the pure ECMWF forecasts at eight locations in the southern half of mainland Spain and the Canary Islands, which received high loadings of African dust for 2013 and 2014. Results for 1-day forecasts are presented. Although clouds play a major role, aerosols have a significant effect, but at shorter time scales. The combination of ECMWF and MACC forecasts gives the best global results, improving the DNI forecasts in events with high aerosol content. The regional BSC-DREAM8b yields good results for some extremely high dust conditions, although more reliable predictions, valid for any aerosol conditions, are provided by the MACC model

The influence of specific domains of self-concept on the school engagement of secondary school students

El objetivo de este estudio es analizar la capacidad predictiva de los dominios específicos del autoconcepto en la implicación escolar del alumnado de educación secundaria. La muestra está compuesta por 484 estudiantes (47.31% hombres y 52.69% mujeres; Medad = 14.89 años, DT = 1.99) de centros públicos y privados de la Comunidad Autónoma Vasca. Los análisis estadísticos se realizan mediante el programa estadístico SPSS v.22. Los principales resultados de esta investigación evidencian la capacidad predictiva del autoconcepto académico sobre la implicación emocional, conductual y cognitiva en la escuela. Asimismo, los datos revelan que el autoconcepto físico, social y personal también contribuirían a explicar la implicación del alumnado en la escuela. Estos resultados ponen de manifiesto la necesidad de profundizar en la contribución del autoconcepto no académico al ajuste escolar durante la adolescencia.The aim of this study is to analyze the predictive ability of specific domains of self-concept in school engagement of secondary school students. The sample consists of 484 students (47.31% men and 52.69% women; Mage = 14.89 years, SD = 1.99) from public and private schools from the Basque Autonomous Community. The statistical analyses were performed using SPSS v.22 software. The main results of this research provide evidence for the predictive ability of academic self-concept in emotional, behavioural, and cognitive engagement in school. Additionally, the data show that physical, social, and personal selfconcept may also help to explain the engagement of students in school. These results point out the need of deepen the contribution of non-academic self-concept to school adjustment during adolescence.Trabajo realizado al amparo de una Ayuda para la Formación de Personal Universitario (FPU13/00835) del Ministerio de Educación, Cultura y Deporte de España. Esta investigación forma parte del trabajo realizado dentro del Grupo Consolidado de Investigación del Sistema Universitario Vasco IT701-13 y de los resultados del proyecto de investigación EHUA13/26 de la Universidad del País Vasco

Mutual optical injection in coupled DBR laser pairs

We report an experimental study of nonlinear effects, characteristic of mutual optical coupling, in an ultra-short coupling regime observed in a distributed Bragg reflector laser pair fabricated on the same chip. Optical feedback is amplified via a double pass through a common onchip optical amplifier, which introduces further nonlinear phenomena. Optical coupling has been introduced via back reflection from a cleaveended fibre. The coupling may be varied in strength by varying the distance of the fibre from the output of the chip, without significantly affecting the coupling time. © 2008 Optical. Society of America

Cerebroespinal fluid control of neurogenesis induced by retinoic acid during early brain development

Producción CientíficaEmbryonic-cerebrospinal fluid (E-CSF) plays crucial roles in early brain development including the control of neurogenesis. Although FGF2 and lipoproteins present in the E-CSF have previously been shown to be involved in neurogenesis, the main factor triggering this process remains unknown. E-CSF contains all-trans-retinol and retinol-binding protein involved in the synthesis of retinoic acid (RA), a neurogenesis inducer. In early chick embryo brain, only the mesencephalic-rombencephalic isthmus (IsO) is able to synthesize RA. Here we show that in chick embryo brain development: (1) E-CSF helps to control RA synthesis in the IsO by means of the RBP and all-trans-retinol it contains; (2) E-CSF has retinoic acid activity, which suggests it may act as a diffusion pathway for RA; and (3) the influence of E-CSF on embryonic brain neurogenesis is to a large extent due to its involvement in RA synthesis. These data help to understand neurogenesis from neural progenitor cells2015-05-2

Embryonic Cerebrospinal Fluid Collaborates With the Isthmic Organizer To Regulate Mesencephalic Gene Expression

Producción CientíficaEarly in development, the behavior of neuroepithelial cells is controlled by several factors acting in a developmentally regulated manner. Recently it has been shown that diffusible factors contained within embryonic cerebrospinal fluid (CSF) promote neuroepithelial cell survival, proliferation, and neurogenesis in mesencephalic explants lacking any known organizing center. In this paper, we show that mesencephalic and mesencephalic þ isthmic organizer explants cultured only with basal medium do not express the typically expressed mesencephalic or isthmic organizer genes analyzed (otx2 and fgf8, respectively) and that mesencephalic explants cultured with embryonic CSF-supplemented medium do effect such expression, although they exhibit an altered pattern of gene expression, including ectopic shh expression domains. Other trophic sources that are able to maintain normal neuroepithelial cell behavior, i.e., fibroblast growth factor-2, fail to activate this ectopic shh expression. Conversely, the expression pattern of the analyzed genes in mesencephalic þ isthmic organizer explants cultured with embryonic cerebrospinal fluid-supplemented medium mimics the pattern for control embryos developed in ovo. We demonstrate that embryonic CSF collaborates with the isthmic organizer in regulation of the expression pattern of some characteristic neuroectodermal genes during early stages of central nervous system (CNS) development, and we suggest that this collaboration is not restricted to the maintenance of neuroepithelial cell survival. Data reported in this paper corroborate the hypothesis that factors contained within embryonic CSF contribute to the patterning of the CNS during early embryonic development.2015-09-0

Photogrammetric state of degradation assessment of decorative claddings: the plasterwork of the Maidens' Courtyard (The Royal Alcazar of Seville)

Highlights: • The photogrammetric survey demonstrates to be a potential tool in the preventive conservation of ancient plasterworks. • The high-precision 3D model allows the study and quantification of alterations (e.g. fissures, deformations, and loss of mass or polychromies). • The virtual model and the analysis performed with CloudCompare software provide fast, accurate and accessible results to experts in the field. Abstract: Previous studies and documentation about the state of conservation of architectural or decorative elements are crucial for heritage managers, technicians and researchers to succeed in the maintenance and preservation of the heritage. In this sense, hand tracings, digital drawings, or photographs have traditionally been the methods for alteration and sample mapping. In spite of their effectiveness, these methods have some disadvantages, such as the need for more precision in terms of location, dimensions, quantification and types of alterations. By contrast, high-resolution three-dimensional (3D) models allow us to analyse decorative ancient plasterworks with great precision, offering considerable advantages over traditional tools for heritage documentation. To facilitate stakeholders’ work and enhance the quality of data collected, this work proposes the use of photogrammetry as a tool for the documentation of polychromed ancient plasterworks, taking the upper frieze of the access door to the Charles V ceiling room in the Royal Alcazar of Seville as a case of study. Thus, the work methodology applied has shown several advantages over previous methods. On the one hand, it was possible to obtain a 2D planimetry from the 3D model; this is an essential step for those responsible for heritage, especially in reports prior to restoration interventions. On the other hand, the 3D model created enables present alterations identification, the location of fissures and cracks in their three dimensions (opening, length and depth), deformations measurement and control, the quantification of mass or polychrome loss, and the detached elements digital reconstruction. In this way, highprecision digital results are quickly obtained and accessible to all the experts involved in the heritage conservation and maintenance plan

Embryonic cerebrospinal fluid regulates neuroepithelial survival proliferation and neurogenesis in chick embryos

Producción CientíficaEarly in development, the behavior of neuroepithelial cells is controlled by several factors, which act in a developmentally regulated manner. Dif- fusible factors are secreted locally by the neuroepithelium itself, although other nearby structures may also be involved. Evidence suggests a physio- logical role for the cerebrospinal fluid in the development of the brain. Here, using organotypic cultures of chick embryo neuroepithelial explants from the mesencephalon, we show that the neuroepithelium in vitro is not able to self-induce cell survival, replication, and neurogenesis. We also show that the embryonic cerebrospinal fluid (E-CSF) promotes neuroepithelial stem cell survival and induces proliferation and neurogenesis in mesencephalic explants. These data strongly suggest that E-CSF is involved in the regu- lation of neuroepithelial cells behavior, supporting the hypothesis that this fluid plays a key role during the early development of the central nervous system

First Field Release of a Genetically Engineered, Self-Limiting Agricultural Pest Insect:Evaluating Its Potential for Future Crop Protection

Alternative, biologically-based approaches for pest management are sorely needed and one approach is to use genetically engineered insects. Herein we describe a series of integrated field, laboratory and modeling studies with the diamondback moth, Plutella xylostella, a serious global pest of crucifers. A “self-limiting” strain of Plutella xylostella (OX4319L), genetically engineered to allow the production of male-only cohorts of moths for field releases, was developed as a novel approach to protect crucifer crops. Wild-type females that mate with these self-limiting males will not produce viable female progeny. Our previous greenhouse studies demonstrated that releases of OX4319L males lead to suppression of the target pest population and dilution of insecticide-resistance genes. We report results of the first open-field release of a non-irradiated, genetically engineered self-limiting strain of an agricultural pest insect. In a series of mark-release-recapture field studies with co-releases of adult OX4319L males and wild-type counterparts, the dispersal, persistence and field survival of each strain were measured in a 2.83 ha cabbage field. In most cases, no differences were detected in these parameters. Overall, 97.8% of the wild-type males and 95.4% of the OX4319L males recaptured dispersed <35 m from the release point. The predicted persistence did not differ between strains regardless of release rate. With 95% confidence, 75% of OX4319L males released at a rate of 1,500 could be expected to live between 3.5 and 5.4 days and 95% of these males could be expected to be detected within 25.8–34.9 m from the release point. Moth strain had no effect on field survival but release rate did. Collectively, these results suggest similar field behavior of OX4319L males compared to its wild-type counterpart. Laboratory studies revealed no differences in mating competitiveness or intrinsic growth rates between the strains and small differences in longevity. Using results from these studies, mathematical models were developed that indicate release of OX4319L males should offer efficacious pest management of P. xylostella. Further field studies are recommended to demonstrate the potential for this self-limiting P. xylostella to provide pest suppression and resistance management benefits, as was previously demonstrated in greenhouse studies