Hexagonal Tilings: Tutte Uniqueness

We develop the necessary machinery in order to prove that hexagonal tilings are uniquely determined by their Tutte polynomial, showing as an example how to apply this technique to the toroidal hexagonal tiling.Comment: 12 figure

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

Jóvenes y políticas territoriales de educación y empleo. El impacto del proyecto social de Escuelas Taller de Oficios del municipio La Habana Vieja en las condiciones de vida de un grupo de jóvenes.

El presente informe muestra los resultados de una investigación que tuvo como objetivo general analizar el impacto del proyecto social de escuelas de oficio del municipio La Habana Vieja en las condiciones de vida de un grupo de jóvenes, a partir de la incorporación de los mismos a un proceso de formación y capacitación para el empleo. Entre los principales resultados del estudio, figura un recorrido teórico sobre la relación entre jóvenes, políticas territoriales de empleo y desarrollo local; un análisis de la políticas sociales para la inserción laboral de los jóvenes en Cuba; y la explicitación de los cambios en las condiciones de vida, desde una perspectiva de género. Concluye con reflexiones que dan cuenta de la efectividad de la política territorial de desarrollo local para generar un cambio en las realidades de un grupo de jóvenes que no estudiaban ni trabajaban, antes de insertarse en el proyecto

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

The quasi-cylindrical description of submerged laminar swirling jets

TThe quasi-cylindrical approximation is used to describe numerically the structure of a submerged swirling jet for subcritical values of the swirl ratio S<Sc . The emerging flow structure is affected by the swirling motion, which enhances the entrainment rate of the jet and induces an adverse pressure gradient that reduces its momentum flux. The effect is more pronounced as the swirl ratio S is increased, yielding for sufficiently large values of S a jet with an annular structure. The integration describes the smooth transition towards the far-field self-similar solution for all values of S smaller than a critical value S5Sc , at which the numerical integration fails to converge at a given downstream location. The comparisons with previous experimental results confirm the correspondence between the onset of vortex breakdown and the failure of the quasi-cylindrical approximation

Metallo-organic ensembles of tritopic subphthalocyanine ligands

"This is the peer reviewed version of the following article: M. Ángel Revuelta-Maza, Ettore Fazio, Gema de la Torre and Tomás Torres, Metallo-organic ensembles of tritopic subphthalocyanine ligands, Journal of Porphyrins and PhthalocyaninesVol. 21, No. 12, pp. 782-789 (2017), which has been published in final form at https://doi.org/10.1142/S1088424617500882I. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use Self-Archived Versions"Organic building blocks containing amines and aldehydes can be used for the preparation of complex metallo-organic structures, such as M2L3 triple helicates or face-capped M4L4 tetrahedral cages, through the formation of both dynamic covalent and coordinative linkages during the self-Assembly process. Herein we describe how the subcomponent self-Assembly method can be succesfully applied over a triamine-functionalized subphthalocyanine (SubPc) ligand to build metallo-supramolecular helicates. Two isomeric SubPcs (C1-SubPc1 and C3-SubPc1) have been prepared from the corresponding C1-SubPcI3 and C3-SubPcI3 precursors under optimized Suzuki conditions. We selected the tritopic C3-SubPc1 derivative as ligand for the subcomponent self-Assembly experiments, which involved the reaction with 2-formylpyridine and different Fe(II) salts. The self-Assembly process was mainly studied by mass spectrometry (ESI direct injection techniques), and in all the conditions applied, we could observe the formation of helicate-Type Fe2SubPc3 structures and/or Fe2SubPc4 species, which can be considered as open precursors of Fe4SubPc4 tetrahedral cages. © 2017 World Scientific Publishing Company.Financial support from Comunidad de Madrid, Spain (S2013/MIT- 2841, FOTOCARBON), and Spanish MICINN (CTQ2014-52869-P) is acknowledged

Laminar Craya-Curtet jets

This Brief Communication investigates laminar Craya-Curtet flows, formed when a jet with moderately large Reynolds number discharges into a coaxial ducted flow of much larger radius. It is seen that the Craya-Curtet number, C=(J/sub c//J/sub j/)/sup 1/2/, defined as the square root of the ratio of the momentum flux of the coflowing stream to that of the central jet, arises as the single governing parameter when the boundary-layer approximation is used to describe the resulting steady slender jet. The numerical integrations show that for C above a critical value C/sub c/ the resulting streamlines remain aligned with the axis, while for C<C/sub c/ the entrainment demands of the jet cannot be satisfied by the coflow, and a toroidal recirculation region forms. The critical Craya-Curtet number is determined for both uniform and parabolic coflow, yielding C/sub c/=0.65 and C/sub c/=0.77, respectively. The streamlines determined numerically are compared with those obtained experimentally by flow visualizations, yielding good agreement in the resulting flow structure and also in the value of C/sub c

Niveles de glucosa y triglicéridos en plasma seminal y motilidad espermática en COBAYOS alimentadas con 10% más en energÍa digestible

The objective the study was to determine the levels of glucose and triglycerides in seminal plasma of 10 guinea pigs, which were fed for a period of 2 months with a diet containing 10% more ED. The level of glucose found in seminal plasma was 11.59 ± 0.5 mg/dL and triglyceride value was 55.95 ± 3.2 mg/dL, while the motility was 97% on average. We conclude that in guinea pigs the levels both glucose and triglycerides were increased by major level of ED in feed, but the spermatic motility was not.El objetivo del presente estudio fue determinar los niveles de los componentes energéticos (glucosa y triglicéridos) en el plasma seminal y la motilidad espermática de 10 cobayos, los cuales fueron alimentados por un período de 2 meses con una dieta 10% mayor en energía digestible (ED). El nivel de glucosa encontrado en plasma seminal fue de 11.59 ± 0.5 mg/dL y el valor de triglicéridos fue de 55.95 ± 3.2 mg/dL, mientras que la motilidad promedio fue de 95%. Concluimos que en cobayos los niveles de glucosa y triglicéridos se incrementan al aumentar el nivel de ED en dieta sin producir alteraciones en la motilidad espermática

Correlaciones entre la infección por microquistes de S. lamacanis y CK-MB, Ast y LDH alpacas

El presente estudio tuvo objetivo determinar la correlación entre el número de microquistes de S. lamacanis en miocardio (N°Mq) y los niveles en sangre de las enzimas CK-MB, AST y LDH en alpacas, a fin de usarlos como predictores de salud o grado de infección por sarcocystiosis. Se utilizaron 41 alpacas de 3-5 años de edad del matadero Municipal Ninacaca, Pasco-Perú, las muestras de sangre se colectaron ante-mortem y las de miocardio post-mortem. El 100 % de los animales presentaron microquistes de S. Lamacanis, y los coeficientes de correlación entre el N°Mq y CK-MB fue de 0.17, AST 0.04 y para LDH 0.06. Se concluye que la correlación es muy baja o casi nula, por lo que las enzimas evaluadas no tendrían mayor importancia para determinar daño cardiaco por infección de microquistes de S. Lamacanis en alpacas

Computationally efficient method to construct scar functions

Phys. Rev. E 85, 026214-026219 (2012) Desarrollo de un nuevo y eficiente método para la construcción de funciones de scar a lo largo de las órtbitas periódicas inestables de sistemas clásicamente caótico