Cycle-magic graphs

AbstractA simple graph G=(V,E) admits a cycle-covering if every edge in E belongs at least to one subgraph of G isomorphic to a given cycle C. Then the graph G is C-magic if there exists a total labelling f:V∪E→{1,2,…,|V|+|E|} such that, for every subgraph H′=(V′,E′) of G isomorphic to C, ∑v∈V′f(v)+∑e∈E′f(e) is constant. When f(V)={1,…,|V|}, then G is said to be C-supermagic.We study the cyclic-magic and cyclic-supermagic behavior of several classes of connected graphs. We give several families of Cr-magic graphs for each r⩾3. The results rely on a technique of partitioning sets of integers with special properties

Acoustic analysis of the drainage cycle in a washing machine

Washing machine manufacturers are working towards producing quieter appliances as many people consider noise emission a key factor when buying. Although the spinning cycle is the noisiest, the amount of noise the pump makes is the cause for many users’ complaints. In an attempt to reduce the noise emitted when a washing machine is pumping out, an experimental study was performed. First, the measurement of the sound pressure allowed us to identify the main sources of noise as the electric motor and the vibration of the cabinet. Next, a detailed analysis based on the measurement of the vibration of the cabinet provided information about the predominant radiating panels. It was also inferred that the electromagnetic noise is drowned out by the structure-borne noise. Finally, several proposals to diminish the sound power were analyzed, and a reduction of 3 dBA was achieved by decreasing the contact zone of the pump with the kick plate

Laboulbenials (Ascomicets) Ibèriques. II, noves aportacions

Se añade el género Migomyces y cinco especies, M. dyschirii , Rhachomyces aphaenopsis, Laboulbenia bradycelli , L. clivinalis y L. fasciculata a la flora ibérica . Se comentan además otras especies y se añade Rhachomyces stipitatus , previamente omitido, al catálogo de Laboulbeniales ibéricas.Le genre Misgomyces et cinq espèces, M. dyschirii , Rhachomyces aphaenopsis, Laboulbenia bradycelli , L. clivinalis et L. fasciculata , ainsi que quelques autres données sur diverses espèces et Rhachomyces stipitatus, omise antérieurement, sont ajoutés a la flore ibérique des Laboulbeniales

Washing machine dynamic model to prevent tub collision during transient state

In horizontal-axis washing machines, the front gasket as well as the damping system are crucial owing to the possible collision of the tub with the housing during the transient period. However, most dynamic models for predicting tub motion focus on the steady state and consider only the suspension system without including the gasket. We conducted an experimental study to analyze the effect of the gasket on the transient motion of the tub. The results obtained indicate the necessity of implementing the gasket in the multibody model of a washing machine to accurately predict the tub behavior during this period. The gasket model is formed by a combination of Voigt elements. Stiffness parameters are determined using a load cell, and damping factors are estimated using a process that integrates Adams/View, Matlab optimization algorithms, and displacement measurements that are taken using accelerometers. A D-optimal design used to predict the effect of the gasket parameters reveals that the tub displacement is most sensitive to the changes in linear stiffness in the transversal direction. Finally, the model of the gasket provides a better approach for predicting the tub movement during resonance that can be used in the design phase to avoid tub collision

World heritage cultural landscapes as spatial management tools. The case of the Serra de Tramuntana (Mallorca)

Resume

MODOS COLECTIVOS DE PRODUCCIÓN DEL CONOCIMIENTO DE LOS ACADEMICOS DE LAS UNIVERSIDADES PÚBLICAS MEXICANAS

Actualmente se reconoce la importancia que ha adquirido el conocimiento y el impacto que las políticas para la ciencia y la educación universitaria han tenido en las formas de producción del conocimiento académico. El presente trabajo muestra los hallazgos de una investigación denominada “Modos colectivos de producción de conocimiento en universidades públicas estatales (UPEs)”. La investigación se realizó en 45 universidades con la participación de 506 académicos. Las principales conclusiones señalan que: la academia ha transitado de una actividad personal a una profesión con características comunitarias; el desarrollo heterogéneo de la producción académica ha dependido de las condiciones del entorno institucional caracterizado tanto por las restricciones materiales como por la estructura de las UPEs; existe una tendencia hacia el trabajo colectivo, con objetivos vinculados a las demandas sociales y económicas específicas cuyo costo sólo puede absorber el Estado o aquellos competidores del mundo industrial; se transita entre la pequeña ciencia (realizada por individuos o grupos reducidos) a una gran ciencia caracterizada por grupos de investigadores participantes en programas y redes más amplios, plenamente institucionalizada, altamente profesionalizada y claramente especializada. Finalmente, la producción del conocimiento pasa por un momento dominante que de acuerdo a la tipología de Gibbons y otros autores se inserta en el modo de producción 2 llamado “Modo emergente” en donde predomina una estructura transdisciplinar, heterogénea y heterárquica. La producción de conocimientos se lleva a cabo en un contexto de aplicación y configurado por un conjunto diverso de demandas intelectuales y sociales

The combined use of gold nanoparticles and infrared radiation enables cytosolic protein delivery

Cytosolic protein delivery remains elusive. The inability of most proteins to cross the cellular membrane is a huge hurdle. Here we explore the unique photothermal properties of gold nanorods (AuNRs) to trigger cytosolic delivery of proteins. Both partners, protein and AuNRs, are modified with a protease-resistant cell-penetrating peptide with nuclear targeting properties to induce internalization. Once internalised, spatiotemporal control of protein release is achieved by near-infrared laser irradiation in the safe second biological window. Importantly, catalytic amounts of AuNRs are sufficient to trigger cytosolic protein delivery. To the best of our knowledge, this is the first time that AuNRs with their maximum of absorption in the second biological window are used to deliver proteins into the intracellular space. This strategy represents a powerful tool for the cytosolic delivery of virtually any class of protein

Directional quantum dot emission by soft-stamping on silicon Mie resonators

We present a soft-stamping method to selectively print a homogenous layer of CdSeTe/ZnS core–shell quantum dots (QDs) on top of an array of Si nanocylinders with Mie-type resonant modes. Using this new method, we gain accurate control of the quantum dot's angular emission through engineered coupling of the QDs to these resonant modes. Using numerical simulations we show that the emission into or away from the Si substrate can be precisely controlled by the QD position on the nanocylinder. QDs centered on a 400 nm diameter nanocylinder surface show 98% emission directionality into the Si substrate. Alternatively, for homogenous ensembles placed over the nanocylinder top-surface, the upward emission is enhanced 10-fold for 150 nm diameter cylinders. Experimental PL intensity measurements corroborate the simulated trends with cylinder diameter. PL lifetime measurements reflect well the variations of the local density of states at the QD position due to coupling to the resonant cylinders. These results demonstrate that the soft imprint technique provides a unique manner to directly integrate optical emitters with a wide range of nanophotonic geometries, with potential applications in LEDs, luminescent solar concentrators, and up- and down-conversion schemes for improved photovoltaics

Plasma polyunsaturated fatty acid pattern in active inflammatory bowel disease

Plasma fatty acid patterns were assessed by gas liquid chromatography in 73 patients with active inflammatory bowel disease and 107 healthy controls. The influence of the disease activity on fatty acid profile was also investigated. Plasma fatty acid patterns in patients with ulcerative colitis and Crohn's disease were similar. Plasma C18:3n3 and C22:6n3 were significantly higher in active ulcerative colitis (p = 0.0143 and p < 0.00001 respectively) and in Crohn's disease (p < 0.00001 for both) than in controls, whereas C20:3n6 was significantly lower in patients than in controls, both in ulcerative colitis (p = 0.0001) and in Crohn's disease (p = 0.0041). In more severe disease, plasma polyunsaturated fatty acid concentrations fell with a significant stepwise decrease in the desaturation index (p = 0.0031 in ulcerative colitis and p = 0.0355 in Crohn's disease). Even in patients with severe disease, however, plasma n3 fatty acids (C18:3n3 and C22:6n3) never fell below those of healthy controls. These findings suggest that in active inflammatory bowel disease, an increased biosynthesis might coexist with an increased consumption of polyunsaturated fatty acids. These observations may be of relevance in the pathogenesis of the disease as polyunsaturated fatty acids are involved in tissue eicosanoid synthesis and cellular membrane function, including that of immunocompetent cells. These results also question the rationale of using n3 polyunsaturated fatty acids in the treatment of inflammatory bowel disease