901 research outputs found
A Generic Four-step Methodology For Institutional Analysis
The central hypothesis of this paper is that there may be situations in which the traditional approach to institutional analysis is of limited applicability. Such an approach, which has been called 'comparative institutional analysis', consists of comparing institutional environments and institutional arrangements in terms of specific economic or other efficiency criteria to see which one performs better. However, because of limitations to accurately predict the future performance of alternative institutional settings, comparisons are not always possible. Furthermore, in most cases the only information available is the performance of the current institutional setting. To account for this methodological deficiency, a generic methodology for institutional analysis, which consists of four steps (institutional structure, institutional efficiency, institutional choice, and institutional change), is proposed in this paper. Accordingly, the emphasis switches from evaluating alternative institutional choices to improving current scenarios. To show the validity of this methodology, some results of its application to a case study are presented. Although more research on this four-step methodology is needed, it proved to be robust when applied to the analysis of the governance of irrigated agriculture in the Peninsula of Santa Elena, Ecuador.New Institutional Economics, Governance structures, Institutional Change., Institutional and Behavioral Economics, B52, D02, Q25,
Hybrid confinement of optical and mechanical modes in a bullseye optomechanical resonator
Optomechanical cavities have proven to be an exceptional tool to explore
fundamental and technological aspects of the interaction between mechanical and
optical waves. Such interactions strongly benefit from cavities with large
optomechanical coupling, high mechanical and optical quality factors, and
mechanical frequencies larger than the optical mode linewidth, the so called
resolved sideband limit. Here we demonstrate a novel optomechanical cavity
based on a disk with a radial mechanical bandgap. This design confines light
and mechanical waves through distinct physical mechanisms which allows for
independent control of the mechanical and optical properties. Our device design
is not limited by unique material properties and could be easily adapted to
allow large optomechanical coupling and high mechanical quality factors with
other promising materials. Finally, our demonstration is based on devices
fabricated on a commercial silicon photonics facility, demonstrating that our
approach can be easily scalable.Comment: 16 pages, 11 figure
Comunicación gubernamental pre-covid de los presidentes hispanohablantes en Twitter
On March 11, 2020, the World Health Organization (WHO) officially declared the state of a coronavirus pandemic (SARS-CoV-2) in the world. A statement unprecedented in history, but that the media had been reporting since the previous weeks. With the general objective of analyzing the political communication and media competence that the presidents of the Spanish-speaking countries had the week before the declaration of a pandemic by COVID19, we chose a quantitative investigation due to its importance in data analysis with a flexible method. Through mining with advanced data search algorithms on Twitter, we analyzed 7.650 tweets from the accounts of the 22 presidents and 21 media outlets. Despite the indicators of the WHO and the media, many of the presidents did not have an acceptable political communication and media competence according to the problem addressed.El 11 de marzo de 2020 la Organización Mundial de la Salud (OMS) declaró oficialmente el estado de pandemia por coronavirus (SARS-CoV-2) en el mundo. Una declaración sin precedentes en la historia, pero que desde las semanas previas los medios de comunicación ya estaban informando. Con el objetivo general de analizar la comunicación política y competencia mediática que tuvieron los presidentes de los países hispanohablantes la semana previa a la declaración de pandemia por COVID19, escogimos una investigación cuantitativa por su importancia en el análisis de datos con un método flexible. Mediante la minería con algoritmos de búsqueda avanzada de datos en Twitter analizamos 7.650 tuits de las cuentas de los 22 presidentes y 21 medios de comunicación. A pesar de los indicadores de la OMS y los medios de comunicación, muchos de los presidentes no tuvieron una comunicación política y competencia mediática aceptable acorde con el problema abordado
Oleaginosas de la Amazonía: el inchi.
Cumpliendo con uno de los objetivos de la investigación del Programa Flora Amazónico, sobre potencialidad y aprovechamiento del recurso vegetal basada en el reconocimiento y utilización de las especies vegetales nativas que no necesitan adaptación, y se preseata un informe técnico sobre el Inchi (Caryodendron orinocense), oleaginosas de la familia Enphorbiaceae. Las principales características de esta especie para su aparovechamiento son: siendo nativa de la Amazonía y la Orinoquía, no requiere aclimatación ni adaptación, es excelente para utilizarla en sistemas agrosilviculturales y así rescatar áreas marginadas y producir aceites, se puede cultivar tanto en bajo bosque como a libre exposición, produce aabaundantes frutos cuyo enraizamiento es tardio y las almendras contienen un alto porcentaje de aceite y su poder energético es uno de los más altos encontrados en productos vegetales. El Inchí contiene Fe, P, Na y Mg sufientes para suplir las necesidades y requerimientos humanos, así como todas los aminoacidos esenciales (excepto el triptofáno) y los aminoácidos azufrados. así como los ácidos grasos poli-insaturados, en porcentaje elevado, lo cual inhibe la presencia de colesterol y las enfermedades causadas por los ácidos grasos saturados. Predomina el ácido lindéico, el cual solo se halla en la leche materna y el plasma sanguíneo. Es una especie que merece ser estudiada, cultivada y usada como producto sustentador de parte de la economía agrícola de extensas áreas amazónica
Título: Cuando yo sea maestra
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201
Brillouin Optomechanics In Coupled Silicon Microcavities
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)The simultaneous control of optical and mechanical waves has enabled a range of fundamental and technological breakthroughs, from the demonstration of ultra-stable frequency reference devices, to the exploration of the quantum-classical boundaries in optomechanical laser-cooling experiments. More recently, such an optomechanical interaction has been observed in integrated nano-waveguides and microcavities in the Brillouin regime, where short-wavelength mechanical modes scatter light at several GHz. Here we engineer coupled optical microcavities to enable a low threshold excitation of mechanical travelling-wave modes through backward stimulated Brillouin scattering. Exploring the backward scattering we propose silicon microcavity designs based on laterally coupled single and double-layer cavities, the proposed structures enable optomechanical coupling with very high frequency modes (11 to 25 GHz) and large optomechanical coupling rates (g(0)/2 pi) from 50 kHz to 90 kHz.7Sao Paulo State Research Foundation (FAPESP) [2012/17765-7, 2012/17610-3]National Counsel of Technological and Scientific Development (CNPQ)Coordination for the Improvement of Higher Education Personnel (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Staphylococcus aureus outbreak in the intensive care unit of the largest public hospital in Quito, Ecuador
Staphylococcus aureus is a frequent cause of nosocomial pneumonia and bacteremia worldwide. Classical and molecular epidemiology approaches were used to study a S. aureus outbreak in the intensive care unit (ICU) of one of the largest public hospitals in Quito. Staphylococcus aureus isolates from 17 patients and 19 potential carriers from the staff were collected from March 2007 to February 2008 and analyzed by pulsed-fi eld gel electrophoresis (PFGE) to determine their clonal relationships. During this period the hospital reported 16 cases of hospital-acquired staphylococcal pneumonia and an apparent outbreak occurred from June to September 2007. DNA from these isolates formed six different PFGE patterns: four clonal groups, and two groups of clonally related isolates. Molecular typing failed to identify any staphylococcal reservoir among staff members. The current study suggested that a staphylococcal outbreak that occurred in the summer of 2007 was caused by different bacterial clones, although some clones were shared by two patients. Historical analysis of the staphylococcal infections in the ICU showed a higher incidence during the summer months, which coincided with the programmed personnel shift. This observation suggests that outbreaks might be produced by the introduction of improperly trained personnel. [Int Microbiol 2013; 16(2):81-86]Keywords: Staphylococcus aureus; staphylococal pneumonia; nosocomial outbreaks; MRS
Prototipo de sistema de medida para una instalación eléctrica residencial de topología variable
This paper presents a prototype measurement system accuracy for use in a residential electrical installation with variable topology with renewable energy sources and also it has the public grid supply; the system performs monitoring and control of electrical parameters in each circuit and measures the power consumption by users. To develop an integrated circuit called ADE7763 (Devices, ADE7763 datsheet) was chosen, with high level of accuracy for the voltage and current measurements and serial communication (SPI "Serial Peripheral Interface") (Arduino, s.f.) with Arduino device is implemented as master device to communicate, making the system calibration was performed to determine its accuracy and the ability to use it reliably in a real system. The term variable topology refers to the ability of an installation for dynamically change its settings by switching circuit for selecting one or other power source and supply the load more efficiently. En este artículo se propone un prototipo de sistema de medición de precisión para ser utilizado en una instalación eléctrica residencial de topología variable con fuentes de energía renovable que cuenta también con suministro de la red de distribución pública; el sistema realiza supervisión y control de los parámetros eléctricos en cada circuito y medidas del consumo de energía por parte de los usuarios. Para el desarrollo se eligió un circuito integrado ADE7763 (Devices, ADE7763 datsheet), que cuenta con buen nivel de precisión para realizar la medidas de tensión y corriente y se implementó la comunicación serial (SPI “Serial Peripheral Interface”) (Arduino, s.f.) con Arduino como dispositivo maestro para la comunicación, con lo cual se realizó la calibración del sistema para determinar su precisión y la posibilidad de utilizarlo de manera confiable en un sistema real. El término de topología variable hace referencia a que la instalación de manera dinámica puede cambiar su configuración mediante conmutación de circuitos para seleccionar una u otra fuente de energía y alimentar la carga de manera más eficiente.
Leishmaniose en Equateur : 4. Infestation naturelle du chien par Leishmania panamensis
Dans deux stations de la plaine côtière d'Equateur, région endémique de leishmaniose à #Leishmania panamensis, 34 chiens ont été contrôlés aux plans clinique, sérologique et parasitologique; des tests d'immunofluorescence indirecte et d'électrosynérèse, des ponctions ganglionnaires, des biopsies de lésions ont été pratiqués. De deux chiens présentant des lésions suspectes, un seul avait des lésions de la truffe et du scrotum infectées par des #Leishmania. La souche isolée a été rapportée à #L. panamensis (complexe #L. guyanensis). L'atteinte leishmanienne était strictement tégumentaire. Dans la zone d'étude, le chien semble un hôte accidentel. (Résumé d'auteur
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