A parametrization for the symbols of a Hankel type operator

Hankel operators and their symbols, as generalized by V. Pták and P. Vrbová, are considered. In this more general framework, a linear operator X from a Hilbert space H1 to a Hilbert space H2 is said to be a Hankel operator for given contractions T1 on H1 and T2 on H2 if, and only if, XT ∗ 1 = T2X and X satisfies a boundedness condition that depends on the unitary parts of the minimal isometric dilations V1 of T1 and V2 of T2. A Hankel symbol of X is a dilation Z of X, with a certain norm constraint, such that ZV ∗ 1 = V2Z. The boundedness condition imposed to X has revealed to be essential, indeed necessary and sufficient, for X to admit Hankel symbols. As for a description of the symbols of X, this work provides a parametric labeling of all of them by means of Schur like formula. As a by-product, a new proof of the existence of Hankel symbols is obtained. The proof is established by associating to X, T1 and T2 a suitable isometry V so that there is a bijective correspondence between the symbols of X and the family of all minimal unitary extensions of V.Ministerio de Ciencia y TecnologíaJunta de AndalucíaFondo Nacional de Ciencia, Tecnología e Innovación (Venezuela

Implementación de la metodología de las 5S de Kaizen para mejorar la productividad en las áreas de logística y ventas de Farm Import S.A en la ciudad de Trujillo del 1° trimestre, año 2017

La presente investigación tuvo como propósito determinar si la implementación de la metodología de las 5S de Kaizen contribuirá a mejorar la productividad en las áreas de logística y ventas de Farm Import S.A. en la ciudad de Trujillo del 1° trimestre, año 2017. La metodología empleada en la investigación fue aplicar una encuesta antes y después de la aplicación de la metodología de las 5S de Kaizen, con el propósito de evaluar y medir el nivel de productividad en el que se encontraban sus procesos en un inicio; y determinar, también las causas que la generaban. La población de estudio estuvo constituida por 10 colaboradores, los mismos que fueron considerados como muestra a tratar. Para el tratamiento estadístico de los datos se utilizó la hoja de cálculo Excel, que nos permitió sistematizar la información en tablas y gráficos; en tanto que, para la contratación de la hipótesis se utilizó la prueba de T-student los mismos que posteriormente fueron categorizados. Los resultados demuestran que la aplicación del método de las 5S de Kaizen mejoró en la Productividad en un 40% con la eliminación de desperdicio en tiempo, esfuerzos desaprovechados, etc. Elevando la calidad de servicio, productos, desarrollo de los colaboradores, reduciendo costos de diseño, inventario y distribución y generando clientes más satisfechos las áreas de logística y ventas de la organización, permitiendo una mejor interrelación entre sus miembros y conciencia en sus objetivos propuestos. Finalmente proponemos que las organizaciones apliquen programa de las 5S de Kaizen para mejorar su Productividad.The purpose of the present investigation was to determine if the implementation of Kaizen 5S methodology will contribute to improve productivity in the areas of logistics and sales of Farm Import S.A. In the city of Trujillo of the 1st quarter, year 2017. The methodology used in the research was to apply a survey before and after the application of Kaizen 5S methodology, with the purpose of evaluating and measuring the level of productivity in which their processes were in the beginning; And to determine the causes that generated it. The study population consisted of 10 collaborators, who were considered as a sample to be treated. For the statistical treatment of the data, we used the Excel spreadsheet, which allowed us to systematize the information in tables and graphs; while, for the hypothesis recruitment, the T-student test was used the same ones that were later categorized. The results show that the application of the 5S method of Kaizen improved in the Productivity by 40% with the elimination of waste in time, wasted efforts, etc. Raising the quality of service, products, employee development, reducing design, inventory and distribution costs and generating more satisfied customers in the organization's logistics and sales areas, allowing a better interrelationship between its members and awareness of its proposed objectives. Finally, we propose that the organizations implement Kaizen 5S program to improve its ProductivityTesi

Pb(II) removal using carbon adsorbents prepared by hybrid heating system: Understanding the microwave heating by dielectric characterization and numerical simulation

This work studies the effect of microwaves in the synthesis of carbon adsorbents using pecan nutshell biomass as a precursor in a hybrid multimode microwave cavity avoiding the utilization of chemical activation or susceptors. The dielectric properties were calculated using the cavity perturbation method, and the power distribution of the electromagnetic field inside cavity was obtained by COMSOL Multiphysics. S-350-MW was obtained using at 350 °C and 200 W and it was characterized using elemental analysis, potentiometric titration, FT-IR and nitrogen adsorption isotherms at −196 °C. The adsorption of Pb(II), in single and binary solutions with Cu(II), Cd(II) and Zn(II) in batch systems indicate that the removal of Pb(II) is affected in the presence of Cu(II) due to the competition of these ions as a result of their similarities such as Pauling electronegativity. Finally, the removal of Pb(II) in continuous systems using packed bed columns showed the pH has the most significant effect according to the variance analysis. The finding highlighted the importance of the acidic functional groups in the performance of carbonaceous adsorbents for the removal of Pb(II). Results of this study contribute to the understandings and application of a hybrid heating system and establish the basis of the role of heating processes in the preparation of carbonaceous adsorbents using microwaves. The Pb(II) removal efficiency achieved in this study is significantly higher than the values reported for carbons prepared by using microwave heating which employs susceptors and/or chemical agents reported in literature, demonstrating that it is possible to obtain effective carbon absorbents for the removal of Pb(II) without the use of any additional susceptors or chemical activation

Microwave pyrolysis of pecan nut shell and thermogravimetric, textural and spectroscopic characterization of carbonaceous products

In the present work, the pyrolysis of pecan nut shell was studied using microwave technology at different input power and exposure time. The carbonaceous products were characterized using elemental analysis, potentiometric titration, thermogravimetric analysis, N2 adsorption isotherms at −196 °C and FT-IR spectroscopy. The characteristics of microwave carbonaceous products were compared with carbons prepared by conventional heating and commercial carbons and finally, the interaction of textile dyes with the carbonaceous materials was studied. The results are indicating that it is possible to obtain carbonaceous materials with similar textural parameters in conventional and microwave systems, but for microwave heating the processing times are short (3 min). Also, the exposure time of 2 min of microwave are not enough for the complete depolymerization of the lignocellulosic matrix of the pecan nut shell and significant amount of cellulose and hemicelluloses remain in char after microwave treatment. Finally, all the carbons obtained by microwave heating are microporous materials with a high number of basic groups on their surface and the high molecular size of dyes is controlling the adsorption on these materials

The role of conductive additives on the performance of hybrid carbon xerogels as electrodes in aqueous supercapacitors

Three different hybrid carbon xerogels containing Graphene Oxide (AXGO), Micronized Graphite (AXMG) and Carbon Black (AXCB) were synthesized using an easy, fast and affordable method. These three additives were initially selected to improve the electrical conductivity of the pristine activated carbon xerogel (AX) thus expecting to improve its performance in aqueous supercapacitors. Capacitances of the corresponding devices were measured as a function of current density and results of the high and low charge transfer regime of the supercapacitors were discussed separately. In both regimes, the differences observed between the hybrid electrodes were analyzed on the basis of the concurrent influence of the micro and mesoporosity, surface chemistry and electrical conductivity of the materials. Accordingly, even though all the hybrid carbon xerogels showed higher electrical conductivities, only AXGO rendered a better performance than AX, showing the highest capacitances in the whole interval of intensities studied. Consequently, at 16 A g−1, the energy and power densities of the AXGO supercapacitors increased up to 16% and 97%, respectively, with respect to AX, and of 143% and 409%, respectively, with respect to a commercial activated carbon used as reference. The performance of AXCB and, especially AXMG was worse than AX supercapacitors due to a combination of inadequate pore size distributions and/or a poor surface chemistry. Finally, TEM analysis helped to understand the different way the three additives were affecting the nanostructure (and final properties) of the hybrid carbon xerogels.Authors gratefully acknowledge the financial support from the Ministerio de Economía, Industria y Competitividad from Spain (Project CTQ2017-87820-R). MCR also acknowledges CSIC (Project I.E. 201880E010)

La psicología positiva: antigua o nueva concepción

This paper presents the most important concepts and contents of the field of positive psychology. The psychology born with a positive approach, with three main objectives: to cure mental disorders, make life more accomplishing and productive, and identify the talent and intelligence of the people and develop them. Historically suffers a break from the great wars, which focused interest in solving the damages and their consequences. In the second millennium, rising again from the hand of Martin Seligman and is consolidating with great potential and depth of influence in society. To improve our skills, develop as persons, be happy, enjoy life, are the topics of interest in scientific research of positive psychology.Este trabajo presenta los conceptos y contenidos más importantes del campo de la psicología positiva. La psicología nace con enfoque positivo, con tres grandes objetivos: curar los trastornos mentales, hacer la vida de las personas más plena y productiva, e identificar el talento y la inteligencia de las personas y desarrollarlos. Históricamente sufre un parón por las grandes guerras, las cuales centraron los intereses en resolver los daños y las consecuencias derivadas. En el segundo milenio, vuelve a resurgir de la mano de Martin Seligman y se está consolidando con un gran potencial de influencia y calado en la sociedad. El objetivo de mejorar nuestras capacidades, desarrollarnos como personas, ser felices, disfrutar de la vida, son los temas de interés en la investigación científica de la psicología positiva.

Positive psychology: early or new conception

Este trabajo presenta los conceptos y contenidos más importantes del campo de la psicología positiva. La psicología nace con enfoque positivo, con tres grandes objetivos: curar los trastornos mentales, hacer la vida de las personas más plena y productiva, e identificar el talento y la inteligencia de las personas y desarrollarlos. Históricamente sufre un parón por las grandes guerras, las cuales centraron los intereses en resolver los daños y las consecuencias derivadas. En el segundo milenio, vuelve a resurgir de la mano de Martin Seligman y se está consolidando con un gran potencial de influencia y calado en la sociedad. El objetivo de mejorar nuestras capacidades, desarrollarnos como personas, ser felices, disfrutar de la vida, son los temas de interés en la investigación científica de la psicología positiva.This paper presents the most important concepts and contents of the field of positive psychology. The psychology born with a positive approach, with three main objectives: to cure mental disorders, make life more accomplishing and productive, and identify the talent and intelligence of the people and develop them. Historically suffers a break from the great wars, which focused interest in solving the damages and their consequences. In the second millennium, rising again from the hand of Martin Seligman and is consolidating with great potential and depth of influence in society. To improve our skills, develop as persons, be happy, enjoy life, are the topics of interest in scientific research of positive psychology.peerReviewe

Innovation paths in wind power: insights from Denmark and Germany

Denmark and Germany both make substantial investments in low carbon innovation, not least in the wind power sector. These investments in wind energy are driven by the twin objectives of reducing carbon emissions and building up international competitive advantage. Support for wind power dates back to the 1970s, but it has gained particular traction in recent years thus opening up new innovation paths. This paper explores the key features, similarities and differences in innovation paths in Denmark and Germany and sheds light on their main determinants. The paper shows that there are many commonalities between Denmark and Germany when it comes to innovation pathways, both in technological and organisational innovation. In turbine technology, the similarities are the constant increase in turbine size and quality. The key difference to be found is the relative importance of different turbine designs. The ‘Danish Design’ remains the global standard. The direct drive design, while uncommon in Denmark, dominates the German installation base. Direct drive technology has thus emerged as a distinctly German design and sub-trajectory within the overall technological innovation path. When it comes to organising wind turbine deployment, both countries have moved along broadly similar paths. There are now fewer turbines deployed than at any time in the past 10 to 20 years, but on average these are concentrated in larger projects and the production capacity and total electricity output has increased significantly in both countries. The key difference is in the role of the offshore segment in deployment: Denmark has been a pioneer in the offshore segment, which has hitherto played a much smaller role in Germany. While this paper shows that there are many common features between the two countries, it also identifies a diversity of pathways, or rather, a co-existence of different sub-trajectories in both core technology and in the organisation of deployment. It is as yet unclear whether the future will bring more convergence or divergence. To address this, the paper explores specific determinants of innovation paths: government policies, demand conditions, geography, value chains, and the strategies undertaken by firms. It demonstrates that the innovation paths common to both countries have roots in a confluence of determining factors which are mainly due to social and political priorities, preferences and decisions at national level. However, the sub-trajectories, which create variation between Denmark and Germany, differ in this regard. They tend to have roots in ‘given’ geographical conditions and in company-level technology choices. In other words, many of the similarities in innovation paths between Denmark and Germany have common national causes, while company-specific strategies also influence the innovation paths in significant ways. This raises important questions about the national specificity of innovation paths in wind power development. Finally, the paper briefly addresses the increasing global interconnectedness of wind technology markets and the role of emerging new players, such as China and India

Trypanosoma cruzi co-infections with other vector borne diseases are frequent in dogs from the pacific coast of Ecuador

Este articulo describe la presentación de infecciones múltiples con Trypnosoma cruzi, Anaplasma spp., Dirofilaria immitis y Ehrlichia spp. (transmitidas por vector) en perros de una región de la costa del Pacífico de EcuadorDogs are a reservoir for Chagas disease, caused by Trypanosoma cruzi (T. cruzi), and other companion vectorborne diseases, including ehrlichiosis (Ehrlichia canis and Ehrlichia ewingii), anaplasmosis (Anaplasma phagocytophilum and Anaplasma platys), dirofilariasis (Dirofilaria immitis) and Lyme disease (Borrelia burgdorferi). This study has two key objectives: 1) to determine seroreactivity against T. cruzi in dogs from the town of Col´on, in Portoviejo city, in the central coast of Ecuador; and 2) to establish the coinfection frequency of other companion vector-borne diseases in dogs positive for T. cruzi. Antibodies against T. cruzi were detected using two enzymelinked immunosorbent assays. Diagnostic consensus between ELISA tests was established using the Cohen’s Kappa coefficient. Other haemoparasitic diseases were detected using the IDEXX SNAP® 4Dx® kit in dogs previously diagnosed as T. cruzi-seropositive. From 84 dogs sampled, 57.14% (48/84) tested positive for T. cruzi. Co-infection analysis of 25 dogs positive for T. cruzi revealed antibodies also against Ehrlichia spp. (48%), Anaplasma spp. (28%), and Dirofilaria immitis (12%). These results provide a novel perspective regarding the status of these pathogens which co-infect dogs in Col´on. Since all these pathogens are zoonotic, our findings should warn regional health authorities to implement sanitary programs, to better prevent and control vectors associated to these pathogens. On the other hand, human and veterinarian doctors, should consider that patients with a cardiac infection condition could be suffering co-infections with two or more vector transmitted pathogens.RMJ The research was funded by the Universidad Autónoma del Estado de México (UAEM) Project (4351/2017/CI). NJG National Institute of Allergy and Infectious Diseases (R01AI136031) of the National Institutes of Health