592 resultados para OVERGROWN GAN


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As a result of a floristic survey carried out in riparian habitats of northern Spain, new chorological data are provided for 9 alien and 6 native plant species. Some species are reported for the first time at regional scale, such as Carex strigosa, Helianthus x laetiflorus and Persicaria pensylvanica in Cantabria. Also noteworthy is the finding of naturalised populations of the North American grass Muhlenbergia schreberi at the Urumea river basin, which represents the second reference for the Iberian Peninsula.

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Research on women prisoners and drug use is scarce in our context and needs theoretical tools to understand their life paths. In this article, I introduce an intersectional perspective on the experiences of women in prison, with particular focus on drug use. To illustrate this, I draw on the life story of one of the women interviewed in prison, in order to explore the axes of inequality in the lives of women in prison. These are usually presented as accumulated and articulated in complex and diverse ways. The theoretical tool of intersectionality allows us to gain an understanding of the phenomenon of women prisoners who have used drugs. This includes both the structural constraints in which they were embedded and the decisions they made, considering the circumstances of disadvantage in which they were immersed. This is a perspective which has already been intuitively present since the dawn of feminist criminology in the English-speaking world and can now be developed further due to new contributions in this field of gender studies.

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Schistosomiasis is a neglected tropical disease that affects more than 200 million people worldwide. The main disease-causing agents, Schistosoma japonicum, S. mansoni and S. haematobium, are blood flukes that have complex life cycles involving a snail intermediate host. In Asia, S. japonicum causes hepatointestinal disease (schistosomiasis japonica) and is challenging to control due to a broad distribution of its snail hosts and range of animal reservoir hosts. In China, extensive efforts have been underway to control this parasite, but genetic variability in S. japonicum populations could represent an obstacle to eliminating schistosomiasis japonica. Although a draft genome sequence is available for S. japonicum, there has been no previous study of molecular variation in this parasite on a genome-wide scale. In this study, we conducted the first deep genomic exploration of seven S. japonicum populations from mainland China, constructed phylogenies using mitochondrial and nuclear genomic data sets, and established considerable variation between some of the populations in genes inferred to be linked to key cellular processes and/or pathogen-host interactions. Based on the findings from this study, we propose that verifying intraspecific conservation in vaccine or drug target candidates is an important first step toward developing effective vaccines and chemotherapies against schistosomiasis.

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Bulk gallium nitride (GaN) power semiconductor devices are gaining significant interest in recent years, creating the need for technology computer aided design (TCAD) simulation to accurately model and optimize these devices. This paper comprehensively reviews and compares different GaN physical models and model parameters in the literature, and discusses the appropriate selection of these models and parameters for TCAD simulation. 2-D drift-diffusion semi-classical simulation is carried out for 2.6 kV and 3.7 kV bulk GaN vertical PN diodes. The simulated forward current-voltage and reverse breakdown characteristics are in good agreement with the measurement data even over a wide temperature range.

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GaN, InP and GaAs nanowires were investigated for piezoelectric response. Nanowires and structures based on them can find wide applications in areas purposes such as nanogenarators, nanodrives, Solar cells and other perspective areas. Experemental measurements were carried out on AFM Bruker multimode 8 and data was handled with Nanoscope software. AFM techniques permitted not only to visualize the surface topography, but also to show distribution of piezoresponse and allowed to calculate its properties. The calculated values are in the same range as published by other authors.

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Forskning visar att flerspråkiga elevers matematikresultat sjunker i takt med att antalet flerspråkiga elever ökar i klassrummen. Forskningsresultaten visar att flerspråkiga elever framförallt har svårt för problemlösningsuppgifter med mycket text. Frågan är om lärare har tillräckligt med kunskaper och resurser för att tillgodose alla elevers behov. Syftet med vår litteraturstudie är att undersöka vilka strategier lärare kan använda för att stödja flerspråkiga elever. Vidare tar litteraturstudien upp vad som är betydelsefullt för att flerspråkiga elever ska kunna utveckla sin problemlösningsförmåga. I denna litteraturstudie har vetenskapligt granskade texter sökts och upptäckts via användning av olika söktekniker och därefter analyserats. Sökmetoderna vi har använt är slumpmässig sökning, systematisk sökning och kedjesökning. I litteraturstudien förekommer avhandlingar, konferensbidrag, empiriska undersökningar och artiklar i vetenskapligt granskade tidskrifter. Resultatet av vår litteraturstudie visar att flerspråkiga elever påverkas av flera olika faktorer. Lärare har en betydande roll för att eleverna ska kunna utveckla problemlösningsförmågan i ämnet matematik. Vårt resultat tar upp aspekter som lärare i ett mångkulturellt klassrum bör ta hänsyn till i undervisningen. De aspekter som tas upp i litteraturstudien är huruvida lärare tar hänsyn till elevernas tidigare erfarenheter och deras kultur. Ett viktigt begrepp inom detta område som behandlas i litteraturstudien är det etnomatematiska perspektivet. Vidare visar litteraturstudiens resultat att de flerspråkiga elevernas tillgång till sitt modersmål är en väsentlig del för att utveckla matematiska färdigheter. Fortsättningsvis visar resultatet att lärares val av kontextanknutna uppgifter är avgörande för att flerspråkiga elever ska kunna se en helhet i matematiska textuppgifter. Slutligen visar resultatet att det är viktigt att flerspråkiga elever måste ges möjlighet att tala matematik och att lärare belyser viktiga matematiska begrepp i klassrummet. 

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Las ESS son organizaciones creadas en 1993 con el fin de cumplir dos propósitos fundamentales: gestionar la adquisición por parte de las comunidades de servicios de salud financiadosmediante el subsidio directo otorgado por el Estado para este fin, yfacilitar la organización y desarrollo de las comunidades a través de la difusión de la cultura de la solidaridad. En el primer semestre de 1998, el Centro de Investigaciones en Desarrollo, Cimder, adscrito a la Universidad del Valle, ganó un concurso público para adelantar una evaluación comprensiva del funcionamiento de este tipo de organizaciones. En este documento se presentan algunas reflexiones de uno de los autores de la evaluación citada.

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We compare the optical properties and device performance of unpackaged InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) emitting at ∼430 nm grown simultaneously on a high-cost small-size bulk semipolar (11 2 - 2) GaN substrate (Bulk-GaN) and a low-cost large-size (11 2 - 2) GaN template created on patterned (10 1 - 2) r-plane sapphire substrate (PSS-GaN). The Bulk-GaN substrate has the threading dislocation density (TDD) of ∼ and basal-plane stacking fault (BSF) density of 0 cm-1, while the PSS-GaN substrate has the TDD of ∼2 × 108cm-2 and BSF density of ∼1 × 103cm-1. Despite an enhanced light extraction efficiency, the LED grown on PSS-GaN has two-times lower internal quantum efficiency than the LED grown on Bulk-GaN as determined by photoluminescence measurements. The LED grown on PSS-GaN substrate also has about two-times lower output power compared to the LED grown on Bulk-GaN substrate. This lower output power was attributed to the higher TDD and BSF density.

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Syftet med denna uppsats var att genom ett salutogent perspektiv få en ökad förståelse för, inom äldreomsorgen verksamma, biståndshandläggares arbetssituation samt att undersöka vad som kan bidra till att biståndshandläggares arbetssituation upplevs som lättare och mindre påfrestande. Metoden som använts är kvalitativa intervjuer där sex biståndshandläggare verksamma i Värmland har intervjuats. Intervjuerna analyserades genom teman ur KASAM och resulterade i kategorier under varje tema. Under temat begriplighet framkom att biståndshandläggare får stöd från sina kollegor men att de också önskar att det fanns mer resurser för handledning. Biståndshandläggare utför mer än vad som ingår i arbetsbeskrivningen. Under temat hanterbarhet framgår att hög arbetsbelastning hanteras genom att biståndshandläggarna måste planera, strukturera och prioritera. Kollegornas stöd gör arbetet lättare att hantera då de genom att prata med varandra bearbetar känslomässigt påfrestande delar av arbetet. De uttryckte olika behov av att reflektera över sitt arbete. Biståndshandläggare har en stor frihet att planera sin egen arbetsdag och de samverkar med andra professioner. Under temat meningsfullhet framgår att biståndshandläggare finner mening i att göra skillnad för den enskilde. Vårt resultat visar att biståndshandläggarna är utsatta för stress i sitt arbete och att de också har förmåga att möta stressen, men förmågan att möta stressen minskar när arbetsbelastningen blir för hög. 

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Un sistema de garantía de depósitos puede contribuir a la estabilidad financiera, siempre que cuente con fondos adecuados y otros mecanismos de salvaguardia, como un sólido programa de supervisión bancaria. En la fábula de Esopo sobre la liebre y la tortuga, la tortuga aceptó echar una carrera con la liebre. La liebre, mucho más veloz que la tortuga, salió corriendo a toda velocidad en el primer tramo de la carrera, pero después se acostó a dormir una siesta, convencida de que podría adelantar a su contrincante. Cuando despertó, la tortuga, que había avanzado lentamente pero con constancia, se estaba acercando a la meta. La liebre no pudo alcanzar a la tortuga y ésta ganó la carrera. Un sistema de garantía de depósitos eficaz se asemeja más a una tortuga que a una liebre. A primera vista parece que puede establecerse rápidamente y con facilidad un sistema nacional de garantía de depósitos que anuncie una garantía pública para los depósitos de los bancos. Algunos países, a fin de evitar el retiro masivo de depósitos que podría llevar a la quiebra a los bancos en situación sólida y a fin de estabilizar un sistema bancario en dificultades, han intentado crear un sistema de garantía de depósitos de esta forma. Lamentablemente, a menos que el sistema cuente con fondos suficientes para hacer frente a una grave crisis financiera y con un sólido programa de supervisión bancaria, este sistema está destinado al fracaso

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Understanding how aquatic species grow is fundamental in fisheries because stock assessment often relies on growth dependent statistical models. Length-frequency-based methods become important when more applicable data for growth model estimation are either not available or very expensive. In this article, we develop a new framework for growth estimation from length-frequency data using a generalized von Bertalanffy growth model (VBGM) framework that allows for time-dependent covariates to be incorporated. A finite mixture of normal distributions is used to model the length-frequency cohorts of each month with the means constrained to follow a VBGM. The variances of the finite mixture components are constrained to be a function of mean length, reducing the number of parameters and allowing for an estimate of the variance at any length. To optimize the likelihood, we use a minorization–maximization (MM) algorithm with a Nelder–Mead sub-step. This work was motivated by the decline in catches of the blue swimmer crab (BSC) (Portunus armatus) off the east coast of Queensland, Australia. We test the method with a simulation study and then apply it to the BSC fishery data.

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En el presente trabajo se parte de un marco teórico, que contempla los conceptos y principios básicos de la Atención Primaria de Salud [APS], de los Sistemas Locales de Salud [SILOS], poniendo énfasis en las formas de Participación Comunitaria por ser uno de los ejes principales en el que se sustenta la APS. Luego mediante la aplicación de la Participación Comunitaria en la parroquia Jerusalén, se obtuvieron los siguientes resultados: El equipo de salud logró concientizarse de los problemas existentes en la comunidad y se incorporó al trabajo comunitario con lo cual se ganó confianza, credibilidad y capacidad de asesoramiento; se identificó, reestructuró y conformó organizaciones comunitarias de acuerdo a las necesidades, con dichas organizaciones se realizó el Diagnóstico Participativo de Salud, que engloba: un censo poblacional y de migración mediante mapas parlantes elaborados por la comunidad, identificación de las patologías más frecuentes y de familias en riesgo y por último se priorizó y seleccionó como problema de acuerdo a la frecuencia, importancia y vulnerabilidad la falta de agua apta para el consumo. Para resolver este problema se utilizó una de las herramientas de la Gerencia de Calidad Total que es el Microproyecto, en donde la comunidad participó en la fase de Planificación, Ejecución y Evaluación, obteniéndose: El mejoramiento de los Conocimientos, Actitudes y Prácticas [CAPs] en la desinfección del agua mediante el método de clorificación; autogestión comunitaria para la compra de un equipo productor de cloro. Racionalización del consumo del agua, por último mediante la coordinación interinstitucional con el municipio del cantón Biblián y la Subsecretaría de Saneamiento Ambiental, se obtuvo una partida presupuestaria para la construcción del desarenador, la comunidad por su parte aportó con mano de obra a través de la organización de mingas.

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The thesis aims to exploit properties of thin films for applications such as spintronics, UV detection and gas sensing. Nanoscale thin films devices have myriad advantages and compatibility with Si-based integrated circuits processes. Two distinct classes of material systems are investigated, namely ferromagnetic thin films and semiconductor oxides. To aid the designing of devices, the surface properties of the thin films were investigated by using electron and photon characterization techniques including Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), grazing incidence X-ray diffraction (GIXRD), and energy-dispersive X-ray spectroscopy (EDS). These are complemented by nanometer resolved local proximal probes such as atomic force microscopy (AFM), magnetic force microscopy (MFM), electric force microscopy (EFM), and scanning tunneling microscopy to elucidate the interplay between stoichiometry, morphology, chemical states, crystallization, magnetism, optical transparency, and electronic properties. Specifically, I studied the effect of annealing on the surface stoichiometry of the CoFeB/Cu system by in-situ AES and discovered that magnetic nanoparticles with controllable areal density can be produced. This is a good alternative for producing nanoparticles using a maskless process. Additionally, I studied the behavior of magnetic domain walls of the low coercivity alloy CoFeB patterned nanowires. MFM measurement with the in-plane magnetic field showed that, compared to their permalloy counterparts, CoFeB nanowires require a much smaller magnetization switching field , making them promising for low-power-consumption domain wall motion based devices. With oxides, I studied CuO nanoparticles on SnO2 based UV photodetectors (PDs), and discovered that they promote the responsivity by facilitating charge transfer with the formed nanoheterojunctions. I also demonstrated UV PDs with spectrally tunable photoresponse with the bandgap engineered ZnMgO. The bandgap of the alloyed ZnMgO thin films was tailored by varying the Mg contents and AES was demonstrated as a surface scientific approach to assess the alloying of ZnMgO. With gas sensors, I discovered the rf-sputtered anatase-TiO2 thin films for a selective and sensitive NO2 detection at room temperature, under UV illumination. The implementation of UV enhances the responsivity, response and recovery rate of the TiO2 sensor towards NO2 significantly. Evident from the high resolution XPS and AFM studies, the surface contamination and morphology of the thin films degrade the gas sensing response. I also demonstrated that surface additive metal nanoparticles on thin films can improve the response and the selectivity of oxide based sensors. I employed nanometer-scale scanning probe microscopy to study a novel gas senor scheme consisting of gallium nitride (GaN) nanowires with functionalizing oxides layer. The results suggested that AFM together with EFM is capable of discriminating low-conductive materials at the nanoscale, providing a nondestructive method to quantitatively relate sensing response to the surface morphology.

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La coalición de fuerzas políticas que sostuvo el gobierno Fernando Henrique Cardoso durante cerca de ocho años entró definitivamente en crisis. El origen de esta crisis se encuentra en el agotamiento de una política económica que parecía exitosa en su comienzo pero que llevó de hecho el país a una de las más graves crisis de su historia.Esta fue la historia de las experiencias neoliberales de los años 90. Salinas duró seis años de esplendor, hasta la crisis del 94. Menen alcanzó reelegirse una vez pero no logró la segunda reelección hasta que su país entró en la dramática crisis actual. Fujimori también logró una reelección y cayó cuando quiso imponer su tercer mandato. En Venezuela la crisis explotó en el “Caracazo”, con Andrés Pérez en el gobierno, pero fue suplantada con más diez años de consenso neoliberal, que ganó la mayoría de la izquierda y pasó el bastión de la oposición al líder del intento insurreccional que se ligara al “Caracazo”: Hugo Chávez.

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PAPER Trapping phenomena in AlGaN and InAlN barrier HEMTs with different geometries S Martin-Horcajo1, A Wang1, A Bosca1, M F Romero1, M J Tadjer1,2, A D Koehler2, T J Anderson2 and F Calle1 Published 11 February 2015 • © 2015 IOP Publishing Ltd Semiconductor Science and Technology, Volume 30, Number 3 Article PDF Figures References Citations Metrics 350 Total downloads Cited by 1 articles Export citation and abstract BibTeX RIS Turn on MathJax Share this article Article information Abstract Trapping effects were evaluated by means of pulsed measurements under different quiescent biases for GaN/AlGaN/GaN and GaN/InAlN/GaN. It was found that devices with an AlGaN barrier underwent an increase in the on-resistance, and a drain current and transconductance reduction without measurable threshold voltage change, suggesting the location of the traps in the gate-drain access region. In contrast, devices with an InAlN barrier showed a transconductance and a decrease in drain associated with a significant positive shift of threshold voltage, indicating that the traps were likely located under the gate region; as well as an on-resistance degradation probably associated with the presence of surface traps in the gate-drain access region. Furthermore, measurements of drain current transients at different ambient temperatures revealed that the activation energy of electron traps was 0.43 eV and 0.38 eV for AlGaN and InAlN barrier devices, respectively. Experimental and simulation results demonstrated the influence of device geometry on the observed trapping effects, since devices with larger gate lengths and gate-to-drain distance values exhibited less noticeable charge trapping effects.