Evidence for diffusional coupling in electrochemical thin layers: implications for surface coverage calibration via electrochemical infrared spectroscopy

The time dependence of the concentration of CO2 in an electrochemical thin layer cavity is studied with Fourier transform infrared spectroscopy (FTIR) in order to evaluate the extent to which the thin layer cavity is diffusionally decoupled from the surrounding bulk electrolyte. For the model system of CO on Pt(111) in 0.1 M HClO4, it is found that the concentration of CO2, formed by electro-oxidation of CO, equilibrates rapidly with the surrounding bulk electrolyte. This rapid equilibration indicates that there is diffusion out of the thin layer, even on the short time scales of typical infrared experiments (1-3 min). However, since the measured CO2 absorbance intensity as a function of time is reproducible to within 10%, a new time-dependent method for surface coverage calibration using solution-phase species is proposed.

Matematikläxans fördelar och nackdelar : En intervjustudie av lärares syn på matematikläxor i grundskolans tidigare år

Syftet med denna studie är att få kunskap om lärares syn på matematikläxor i grundskolans tidigare år. Förhoppningen var att få förståelse för lärares syfte med matematikläxor och vilka förmågor eleverna förväntas utveckla med matematikläxors hjälp samt att jämföra vilka för- och nackdelar matematikläxan har. För att undersöka detta har sju intervjuer gjorts med lärare från olika skolor och olika årskurser från 1-6. Samtliga lärare som intervjuats undervisar i matematik. Lärares erfarenheter av läxornas betydelse för matematikundervisningen är ett viktigt område att få kunskap om. De lärare som deltog i intervjuerna uttryckte olika synpunkter på matematikläxan. Något lärarna var överens om var att läxa är en skoluppgift som eleven tar med hem efter skolans slut och arbetar med hemma. Lärarna uttryckte samstämmigt att eleverna inte utvecklar några förmågor med matematikläxans hjälp utan förmågorna utvecklar eleverna i skolan med hjälp av lärarna. Det framgick att samtliga lärare upplevde att matematikläxan var tidskrävande och för att matematikläxan ska nå syftet på bästa möjliga sätt behövs mer tid. Att läxan kopplas till undervisning och uppföljning är centralt för att syftet med matematikläxan ska uppnås enligt de intervjuade lärarna. Av resultaten framgår att några lärare är negativt inställda till matematikläxor för att uppföljning och koppling till undervisningen inte finns med och därför förlorar matematikläxan sitt syfte. Föräldrarnas förutsättningar är väldigt olika som exempelvis att de har svårigheter med det svenska språket eller inte är engagerade i barnets skolgång. Andra lärare är positivt inställda till matematikläxor för att färdighetsträningen och repetitionen är viktig och tiden som behövs för det inte räcker till i skolan.

Knowledge translation in Uganda : a qualitative study of Ugandan midwives' and managers' perceived relevance of the sub-elements of the context cornerstone in the PARIHS framework

BACKGROUND: A large proportion of the annual 3.3 million neonatal deaths could be averted if there was a high uptake of basic evidence-based practices. In order to overcome this 'know-do' gap, there is an urgent need for in-depth understanding of knowledge translation (KT). A major factor to consider in the successful translation of knowledge into practice is the influence of organizational context. A theoretical framework highlighting this process is Promoting Action on Research Implementation in Health Services (PARIHS). However, research linked to this framework has almost exclusively been conducted in high-income countries. Therefore, the objective of this study was to examine the perceived relevance of the subelements of the organizational context cornerstone of the PARIHS framework, and also whether other factors in the organizational context were perceived to influence KT in a specific low-income setting. METHODS: This qualitative study was conducted in a district of Uganda, where focus group discussions and semi-structured interviews were conducted with midwives (n = 18) and managers (n = 5) within the catchment area of the general hospital. The interview guide was developed based on the context sub-elements in the PARIHS framework (receptive context, culture, leadership, and evaluation). Interviews were transcribed verbatim, followed by directed content analysis of the data. RESULTS: The sub-elements of organizational context in the PARIHS framework--i.e., receptive context, culture, leadership, and evaluation--also appear to be relevant in a low-income setting like Uganda, but there are additional factors to consider. Access to resources, commitment and informal payment, and community involvement were all perceived to play important roles for successful KT. CONCLUSIONS: In further development of the context assessment tool, assessing factors for successful implementation of evidence in low-income settings--resources, community involvement, and commitment and informal payment--should be considered for inclusion. For low-income settings, resources are of significant importance, and might be considered as a separate subelement of the PARIHS framework as a whole.

A Resource Centric Approach For Advancing Collaboration Through Hydrologic Data And Model Sharing

HydroShare is an online, collaborative system being developed for open sharing of hydrologic data and models. The goal of HydroShare is to enable scientists to easily discover and access hydrologic data and models, retrieve them to their desktop or perform analyses in a distributed computing environment that may include grid, cloud or high performance computing model instances as necessary. Scientists may also publish outcomes (data, results or models) into HydroShare, using the system as a collaboration platform for sharing data, models and analyses. HydroShare is expanding the data sharing capability of the CUAHSI Hydrologic Information System by broadening the classes of data accommodated, creating new capability to share models and model components, and taking advantage of emerging social media functionality to enhance information about and collaboration around hydrologic data and models. One of the fundamental concepts in HydroShare is that of a Resource. All content is represented using a Resource Data Model that separates system and science metadata and has elements common to all resources as well as elements specific to the types of resources HydroShare will support. These will include different data types used in the hydrology community and models and workflows that require metadata on execution functionality. The HydroShare web interface and social media functions are being developed using the Drupal content management system. A geospatial visualization and analysis component enables searching, visualizing, and analyzing geographic datasets. The integrated Rule-Oriented Data System (iRODS) is being used to manage federated data content and perform rule-based background actions on data and model resources, including parsing to generate metadata catalog information and the execution of models and workflows. This presentation will introduce the HydroShare functionality developed to date, describe key elements of the Resource Data Model and outline the roadmap for future development.

Green logistics: key elements for a well-functioning sustainable logistics system

A growing awareness of the modern society about the direct relationship between a growing global community with increasing total industrial activities on one hand and various environmental problems and a natural limitation of natural resources on the other hand set the base for sustainable or “green” approaches within the supply chain. This paper therefore will look at the issue of “Green Logistics” which seeks to reduce the environmental impact of logistics activities by taking into account functions such as recycling, waste and carbon emission reduction and the use of alternative sources of energy. In order to analyze how these approaches and ideas are being perceived by the system as a whole two models from the area of prospective and scenario planning are being used and described to identify the main drivers and tendencies within the system in order to create feasible hypothesis. Using the URCA/CHIVAS model allows us to identify the driver variables out of a high number of variables that best describe the system “Green Logistics”. Followed by the analysis of the actor’s strategies in the system with the Mactor model it is possible to reduce the complexity of a completely holistic system to a few key drivers that can be analyzed further on. Here the implications of URCA/CHIVAS and Mactor are being used to formulate hypotheses about the perception of Green Logistics and its successful implementation among logistics decision makers by an online survey. This research seeks to demonstrate the usefulness of scenario planning to a highly complex system observing it from all angles and extracting information about the relevant factors of it. The results of this demonstration indicate that there are drivers much beyond the factory walls that need to be considered when implementing successfully a system such as Green Logistics.

Market coupling in the power markets

The thesis analyses the European Unions’ effort to create an integrated pan-European electricity market based on “market coupling” as the proposed allocation mechanism for interconnector transfer capacity. Thus, the thesis’ main focus is if market coupling leads to a price convergence in interlinked markets and how it affects the behavior of electricity price data. The applied research methods are a qualitative, structured literature review and a quantitative analysis of electricity price data. The quantitative analysis relies on descriptive statistics of absolute price differentials and on a Cointegration analysis according to Engle & Granger (1987)’s two step approach. Main findings are that implicit auction mechanisms such as market coupling are more efficient than explicit auctions. Especially the method of price coupling leads to a price convergence in involved markets, to social welfare gains and reduces market power of producers, as shown on the example of the TLC market coupling. The market coupling initiative between Germany and Denmark, on the other hand, is evaluated as less successful and illustrates the complexity and difficulties of implementing market coupling initiatives. The cointegration analysis shows that the time series were already before the coupling date cointegrated, but the statistical significance increased. The thesis suggests that market coupling leads to a price convergence of involved markets and thus functions as method to create a single, integrated European electricity market.

Market coupling in the power markets

A dissertação analisa o esforço dos sindicatos europeus para criar um mercado pan- europeu de electricidade integrada baseada em "mercados combinados", como o mecanismo de alocação de capacidade de transferência de energia entre diferentes sistemas. Assim, o foco principal do estudo é se a integração do mercado leva a uma convergência de preços nos mercados interligados, e como isso afeta o comportamento dos preços de energia elétrica. Os métodos de investigação são uma revisão bibliográfica estruturada qualitativa e uma análise quantitativa de dados de preços de energia elétrica. A análise quantitativa se baseia em estatísticas descritivas das diferenças de preços absolutos e em uma análise de cointegração de acordo com a abordagem de Engle e Granger (1987). As principais conclusões são que os mecanismos de leilões implícitos, tais como a integração de mercado são mais eficientes que os leilões explícitos. Especialmente, o método de acoplamento de preços leva a uma convergência de preços nos mercados envolvidos, a ganhos de bem-estar social e reduz a o poder dos produtores no mercado, como mostra o exemplo da integração mercado TLC. A iniciativa mercados combinados entre a Alemanha ea Dinamarca, por outro lado, é avaliada como de menor sucesso e ilustra a complexidade e as dificuldades de implementação de iniciativas de integração de mercado. A análise de cointegração mostra que as séries temporais já estavam cointegradas antes da data de integração, mas a significância estatística aumentou. A tese sugere que a integração do mercado leva a uma convergência dos preços dos mercados envolvidos e, portanto, funciona como método para criar um mercado de eletricidade único e integrado na Europa.

Illegitimate identity in the middle of an ideological crisis and tensions in the consumption network: a study on why plus-size fashion brands are illegitimate fashion elements

O presente trabalho explora as causas pelas quais o campo da moda plus size carece de legitimidade com as consumidoras plus size. Eu explorei o assunto em três artigos. No primeiro, eu estudo o processo de legitimação de um novo mercado emergente, o mercado da moda plus size brasileira e os desafios para sua a institucionalização. Eu conduzi dezessete entrevistas com consumidoras plus size, uma netnografia em quatro blogs de moda plus size brasileiros e analisei de maneira semiótica um site que vende roupas de moda plus size. Meus resultados indicam que, apesar de ter atores legítimos que promovem essas marcas de moda plus size, o campo da moda plus size ainda é percebido como uma versão vergonhosa do campo da moda. Defendo aqui que o fato de uma das lógicas de campo da moda plus size ser estigma, acaba afetando os projetos identitários das consumidoras de maneira depreciativa, de forma elas não se envolvem em práticas de capital cultural que ocorrem dentro do campo da moda plus size. No segundo artigo, eu conduzi uma introspecção genealógica em que eu pesquisei questões de identidade. Como uma mulher (que se assume ) plus size, eu imaginei que seria relevante para olhar para dentro de mim mesma, a fim de explorar a forma como a minha identidade liga-se com a rede semiótica-material que me rodeia em termos de moda, alimentos e outros elementos. Meus dados vieram tanto de técnicas de introspecção simultâneas, quanto retrospectivas. Em termos teóricos, eu usei a ideia de ―assemblages‖ e eu foquei minha análise tanto nos aspectos materiais da minha rede de consumo, quanto na estabilidade da rede. As consequências da minha assemblage estão ligadas a uma gestão de qualidade total da minha identidade, tanto online como off-line, refletidas em práticas de consumo que se conectam à ideia de uma lógica de consumo bulímica em que o consumo de alimentos e gestão corpo estão interligadas. Por fim, no meu terceiro artigo, eu explorei o conceito de identidade a partir do consumo da moda feminina plus size. Foram feitas catorze entrevistas fenomenológicas, cujos dados foram analisados a partir de uma perspectiva hermenêutica. Três categorias temáticas emergiram da análise de dados: a construção da identidade por meio da moda, elementos de identidade plus size e estratégias criativas para lidar com a falta de produtos para mulheres plus size no varejo. Entre os principais resultados, destacam-se a forma como o termo plus size atua como estigma, influenciando projetos de identidade das consumidoras, o papel do varejo no processo de estigmatização e a saga épica de compras, que envolve um "mercado negro", com a participação de vendedores. Eu concluo discutindo o papel da identidade na instabilidade do campo da moda plus size.

Selective Coupling between Theta Phase and Neocortical Fast Gamma Oscillations during REM-Sleep in Mice

TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

Ketamine alters oscillatory coupling in the hoppocampus

Recent studies show that higher order oscillatory interactions such as cross-frequency coupling are important for brain functions that are impaired in schizophrenia, including perception, attention and memory. Here we investigated the dynamics of oscillatory coupling in the hippocampus of awake rats upon NMDA receptor blockade by ketamine, a pharmacological model of schizophrenia. Ketamine (25, 50 and 75 mg/kg i.p.) increased gamma and high-frequency oscillations (HFO) in all depths of the CA1-dentate axis, while theta power changes depended on anatomical location and were independent of a transient increase of delta oscillations. Phase coherence of gamma and HFO increased across hippocampal layers. Phase-amplitude coupling between theta and fast oscillations was markedly altered in a dose-dependent manner: ketamine increased hippocampal theta-HFO coupling at all doses, while theta-gamma coupling increased at the lowest dose and was disrupted at the highest dose. Our results demonstrate that ketamine alters network interactions that underlie cognitively relevant theta-gamma coupling.

Desenvolvimento de antenas de microfita e antenas DRA Broadband

The search for ever smaller device and without loss of performance has been increasingly investigated by researchers involving applied electromagnetics. Antennas using ceramics materials with a high dielectric constant, whether acting as a substract element of patch radiating or as the radiant element are in evidence in current research, that due to the numerous advantages offered, such as: low profile, ability to reduce the its dimensions when compared to other devices, high efficiency of ratiation, suitability the microwave range and/or millimeter wave, low temperature coefficient and low cost. The reason for this high efficiency is that the dielectric losses of ceramics are very low when compared to commercially materials sold used in printed circuit boards, such as fiberglass and phenolite. These characteristics make ceramic devices suitable for operation in the microwave band. Combining the design of patch antennas and/or dielectric resonator antenna (DRA) to certain materials and the method of synthesis of these powders in the manufacture of devices, it s possible choose a material with a dielectric constant appropriate for the design of an antenna with the desired size. The main aim of this work is the design of patch antennas and DRA antennas on synthesis of ceramic powders (synthesis by combustion and polymeric precursors - Pe- chini method) nanostructured with applications in the microwave band. The conventional method of mix oxides was also used to obtain nanometric powders for the preparation of tablets and dielectric resonators. The devices manufactured and studied on high dielectric constant materials make them good candidates to have their small size compared to other devices operating at the same frequency band. The structures analyzed are excited by three different techniques: i) microstrip line, ii) aperture coupling and iii) inductive coupling. The efficiency of these techniques have been investigated experimentally and compared with simulations by Ansoft HFSS, used in the accurate analysis of the electromagnetic behavior of antennas over the finite element method (FEM). In this thesis a literature study on the theory of microstrip antennas and DRA antenna is performed. The same study is performed about the materials and methods of synthesis of ceramic powders, which are used in the manufacture of tablets and dielectric cylinders that make up the devices investigated. The dielectric media which were used to support the analysis of the DRA and/or patch antennas are analyzed using accurate simulations using the finite difference time domain (FDTD) based on the relative electrical permittivity (er) and loss tangent of these means (tand). This work also presents a study on artificial neural networks, showing the network architecture used and their characteristics, as well as the training algorithms that were used in training and modeling some parameters associated with the devices investigated

Aplicação de superfícies seletivas em frequência para melhoria de resposta de arranjos de antenas planares

This work aims to show how the application of frequency selective surfaces (FSS) in planar antenna arrays become an alternative to obtain desired radiation characteristics from changes in radiation parameters of the arrays, such as bandwidth, gain and directivity. In addition to analyzing these parameters is also made a study of the mutual coupling between the elements of the array. To accomplish this study, were designed a microstrip antenna array with two patch elements, fed by a network feed. Another change made in the array was the use of the truncated ground plane, with the objective of increasing the bandwidth and miniaturize the elements of the array. In order to study the behavior of frequency selective surfaces applied in antenna arrays, three different layouts were proposed. The first layout uses the FSS as a superstrate (above the array). The second layout uses the FSS as reflector element (below the array). The third layout is placed between two FSS. Numerical and experimental results for each of the proposed configurations are presented in order to validate the research