902 resultados para CHRONOPOTENTIOMETRY WITH LINEAR CURRENT SCANNING


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Objectives: To explore the views of eye health professionals and service users on shared community and hospital care for wet or neovascular age-related macular degeneration (nAMD).

Method: Using maximum variation sampling, 5 focus groups and 10 interviews were conducted with 23 service users and 24 eye health professionals from across the UK (consisting of 8 optometrists, 6 ophthalmologists, 6 commissioners, 2 public health representatives and 2 clinical eye care advisors to local Clinical Commissioning Groups). Data were transcribed verbatim and analysed thematically using constant comparative techniques derived from grounded theory methodology.

Results: The needs and preferences of those with nAMD appear to be at odds with the current service being provided. There was enthusiasm among health professionals and service users about the possibility of shared care for nAMD as it was felt to have the potential to relieve hospital eye service burden and represent a more patient-centred option, but there were a number of perceived barriers to implementation. Some service users and ophthalmologists voiced concerns about optometrist competency and the potential for delays with referrals to secondary care if stable nAMD became active again. The health professionals were divided as to whether shared care was financially more efficient than the current model of care. Specialist training for optometrists, under the supervision of ophthalmologists, was deemed to be the most effective method of training and was perceived to have the potential to improve the communication and trust that shared care would require.

Conclusions: While shared care is perceived to represent a promising model of nAMD care, voiced concerns suggest that there would need to be greater collaboration between ophthalmology and optometry, in terms of interprofessional trust and communication.

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A lack of suitable high-performance cathode materials has become the major barrier to their applications in future advanced communication equipment and electric vehicle power systems. In this paper, we have developed a layer-by-layer self-assembly approach for fabricating a novel sandwich nanoarchitecture of multilayered LiV3O8 nanoparticle/graphene nanosheet (M-nLVO/GN) hybrid electrodes for potential use in high performance lithium ion batteries by using a porous Ni foam as a substrate. The prepared sandwich nanoarchitecture of M-nLVO/GN hybrid electrodes exhibited high performance as a cathode material for lithium-ion batteries, such as high reversible specific capacity (235 mA h g-1 at a current density of 0.3 A g-1), high coulombic efficiency (over 98%), fast rate capability (up to a current density of 10 A g-1), and superior capacity retention during cycling (90% capacity retention with a current density of 0.3 A g-1 after 300 cycles). Very significantly, this novel insight into the design and synthesis of sandwich nanoarchitecture would extend their application to various electrochemical energy storage devices, such as fuel cells and supercapacitors.

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Vieten's edited collection brings together papers that were given at the I M Young Memorial Symposium 'Inclusion and Democracy Revisited', held in Amsterdam in 2012. The different chapters presented explore in-depth, Young's models of a 'politics of cultural difference', and a 'politics of positional difference' read in combination with her critique of normalisation. Young regards the latter as decisive to any change for the better when reaching out politically to a fairer and more just democratic society.
With the current political, economic and socio-cultural crisis in mind, the contemporary world of global speed and transformed societies in and beyond Europe needs a refinement of what we understand 'normalisation' and 'difference' to be. How can we connect to each other, and in what ways can Young's 'structural inequality model' be applied to develop alternative outlooks on how to enhance inclusion and democracy in different nation states?

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Ever since the inauguration of EU citizenship, elements of social citizenship have been on the agenda of European integration. European level social benefits were proposed early on, and demands for collective labour rights have followed suit. This chapter uses the theoretical umbrella of transnational social citizenship in order to link transnational access to social benefits and collective labour rights. It promotes transnational rights as the best way to conceptualise EU social citizenship as an institution enabling the enjoyment of EU integration without being forced to forego social rights at other levels. Such a perspective sits well in a collection on EU citizenship and federalism, since it simultaneously challenges demands of renationalisation of social rights in the EU and pleas to reduce EU-level citizenship rights to a merely liberal dimension. Social citizenship as promoted here requires an interactive conceptualisation of regulatory and judicial powers at different levels of government as typical for federal systems.
In linking citizenship with human rights the chapter highlights different statuses of citizens. It argues that the rights constituted by social citizenship derive from a status positivus and a status socialis activus, expanding the time-honoured categories of Jellinek. This concept is developed further by linking the notions of receptive solidarity to the status positivus and the notion of participative solidarity to the status socialis activus. In relation to European Union citizenship it promotes a sustainable transnational social citizenship catering for receptive and participative solidarity.
These ideas contrast with most current discourses on EU citizenship. The stress on social citizenship takes issue with a retreat to mere liberalist notions of EU-level citizenship, and the stress on rights takes issue with conceptualising EU citizenship as a community bond with obligations, downplaying the empowering potential of rights. The difficulty of conceptualising transnational social citizenship is to avoid, on the one hand, taking up the tune of populist discourses imagining those moving beyond state borders as a threat to national social citizenship and, on the other hand, to reject the legitimate fears of those remaining at home of creating rupture in the social fabric of Europe’s society. Promoting transnational social citizenship rights based on receptive and participative solidarity the present chapter aims to contribute to avoiding these pitfalls.

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Molecular dynamics (MD) simulation was carried out to acquire an in-depth understanding of the flow behaviour of single crystal silicon during nanometric cutting on three principal crystallographic planes and at different cutting temperatures. The key findings were that (i) the substrate material underneath the cutting tool was observed for the first time to experience a rotational flow akin to fluids at all the tested temperatures up to 1200 K. (ii) The degree of flow in terms of vorticity was found higher on the (1 1 1) crystal plane signifying better machinability on this orientation in accord with the current pool of knowledge (iii) an increase in the machining temperature reduces the springback effect and thereby the elastic recovery and (iv) the cutting orientation and the cutting temperature showed significant dependence on the location of the stagnation region in the cutting zone of the substrate.

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Birefringence is one of the fascinating properties of the vacuum of quantum electrodynamics (QED) in strong electromagnetic fields. The scattering of linearly polarized incident probe photons into a perpendicularly polarized mode provides a distinct signature of the optical activity of the quantum vacuum and thus offers an excellent opportunity for a precision test of nonlinear QED. Precision tests require accurate predictions and thus a theoretical framework that is capable of taking the detailed experimental geometry into account. We derive analytical solutions for vacuum birefringence which include the spatio-temporal field structure of a strong optical pump laser field and an x-ray probe. We show that the angular distribution of the scattered photons depends strongly on the interaction geometry and find that scattering of the perpendicularly polarized scattered photons out of the cone of the incident probe x-ray beam is the key to making the phenomenon experimentally accessible with the current generation of FEL/high-field laser facilities.

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Cancer clinical trials have been one of the key foundations for significant advances in oncology. However, there is a clear recognition within the academic, care delivery and pharmaceutical/biotech communities that our current model of clinical trial discovery and development is no longer fit for purpose. Delivering transformative cancer care should increasingly be our mantra, rather than maintaining the status quo of, at best, the often miniscule incremental benefits that are observed with many current clinical trials. As we enter the era of precision medicine for personalised cancer care (precision and personalised medicine), it is important that we capture and utilise our greater understanding of the biology of disease to drive innovative approaches in clinical trial design and implementation that can lead to a step change in cancer care delivery. A number of advances have been practice changing (e.g. imatinib mesylate in chronic myeloid leukaemia, Herceptin in erb-B2-positive breast cancer), and increasingly we are seeing the promise of a number of newer approaches, particularly in diseases like lung cancer and melanoma. Targeting immune checkpoints has recently yielded some highly promising results. New algorithms that maximise the effectiveness of clinical trials, through for example a multi-stage, multi-arm type design are increasingly gaining traction. However, our enthusiasm for the undoubted advances that have been achieved are being tempered by a realisation that these new approaches may have significant cost implications. This article will address these competing issues, mainly from a European perspective, highlight the problems and challenges to healthcare systems and suggest potential solutions that will ensure that the cost/value rubicon is addressed in a way that allows stakeholders to work together to deliver optimal cost-effective cancer care, the benefits of which can be transferred directly to our patients.

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OBJECTIVE: To evaluate the impact of age, various forms of cataract, and visual acuity on whole-field scotopic sensitivity screening for glaucoma in a rural population. DESIGN: Clinic-based study with population-based recruitment. SETTING: Jin Shan Township near Taipei, Taiwan. SUBJECTS: Three hundred forty-six residents (ages, > or = 40 years) of Jin Shan Township. INTERVENTIONS: Whole-field scotopic testing, ophthalmoscopy with dilation of the pupils, cataract grading against photographic standards, and screening visual field testing in a random one-third subsample. MAIN OUTCOME MEASURES: Whole-field scotopic sensitivity (in decibels) and diagnostic status as a case of glaucoma, glaucoma suspect, or normal. RESULTS: Participants in Jin Shan Township did not differ significantly in the rate of blindness, low visual acuity, or family history of glaucoma from a random sample of nonrespondents. Scotopic sensitivity testing detected 100% (6/6) of subjects with open-angle glaucoma at a specificity of 80.2%. The mean +/- SE scotopic sensitivity for six subjects with open-angle glaucoma (32.78 +/- 1.51 dB) differed significantly from that of 315 normal individuals (38.51 +/- 0.22 dB), when adjusted for age and visual acuity (P = .05, t test). With linear regression modeling, factors that correlated significantly with scotopic sensitivity were intraocular pressure, screening visual field, best corrected visual acuity, presence of cortical cataract, and increasing age. CONCLUSIONS: Although cataract affects the whole-field scotopic threshold, it appears that scotopic testing may be of value in field-based screening for glaucoma.

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This paper addresses the representation of landscape complexity in stated preferences research. It integrates landscape ecology and landscape economics and conducts the landscape analysis in a three-dimensional space to provide ecologically meaningful quantitative landscape indicators that are used as variables for the monetary valuation of landscape in a stated preferences study. Expected heterogeneity in taste intensity across respondents is addressed with a mixed logit model in Willingness to Pay space. Our methodology is applied to value, in monetary terms, the landscape of the Sorrento Peninsula in Italy, an area that has faced increasing pressure from urbanization affecting its traditional horticultural, herbaceous, and arboreal structure, with loss of biodiversity, and an increasing risk of landslides. We find that residents of the Sorrento Peninsula would prefer landscapes characterized by large open views and natural features. Residents also appear to dislike heterogeneous landscapes and the presence of lemon orchards and farmers' stewardship, which are associated with the current failure of protecting the traditional landscape. The outcomes suggest that the use of landscape ecology metrics in a stated preferences model may be an effective way to move forward integrated methodologies to better understand and represent landscape and its complexity.

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In the UK it is estimated that over 33% of psychiatric patients with enduring mental illness have a substance misuse problem, whilst over 50 % of clients currently accessing drug and alcohol services have a mental health problem. Between 2003 and 2013 in Northern Ireland, there were 741 recorded suicides by patients who were in contact with mental health services. Of this number, 68% (n=501) had a history of either alcohol or drug misuse or both, resulting in an average of 46 patient suicides per year associated with dual diagnosis (University of Manchester 2015).
The current evaluation examined staff attitudes towards working with dual diagnosis (co-existing difficulties) issues, staff confidence in working with clients with dual diagnosis, workers’ perceptions of the South Eastern dual diagnosis strategy and service user perspectives of dual diagnosis service provision.
The purpose of the evaluation was to provide evidence regarding the following in accordance with the current dual diagnosis strategy;
Staff understanding of the concept of dual diagnosis,
Staff attitudes towards working with dual diagnosis,
Staff confidence in working with individuals, who present with dual diagnosis,
Service users’ perspectives of SE Trust provision for dual diagnosis.
Staff views on the South Eastern Trust Dual Diagnosis Strategy.

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A conservação da biodiversidade nunca foi uma assunto tão popular como nas últimas décadas, mas esta popularidade crescente é devida à pior das razões: o passo acelerado da extinção de espécies e habitats. Os ecossistemas tropicais são, ao mesmo tempo, os mais diversos e os mais ameaçados, em parte porque muitos países destas regiões emergem ainda de situações de instabilidade social, económica e política. O Brasil é o maior país Neotropical, onde se encontram alguns dos biomas com maior diversidade e mais ameaçados do planeta. Actualmente, é também um país líder ao nível da planificação e implementação de medidas de conservação da biodiversidade. Vários dos biomas tropicais mais diversos e ameaçados encontram-se em território brasileiro. Dois destes biomas, a Amazónia e o Cerrado, convergem numa região ecotonal sujeita a uma elevada pressão humana, conhecida como o arco do desmatamento. O Araguaia, um dos maiores rios do Brasil, corre ao longo desta paisagem e os efeitos do desmatamento são já evidentes em toda a sua bacia. Por causa do acelerado ritmo de degradação deste ecossistema, torna-se urgente obter uma imagem clara da biodiversidade regional e compreender como e se a estratégia de conservação para esta região é capaz de lidar com as correntes ameaças e alcançar o seu objectivo a longo prazo: conservar a biota regional. Tendo a herpetofauna como grupo-alvo, os nossos objectivos principais foram: aumentar o conhecimento das comunidades de anfíbios e répteis squamata da região do curso médio do Rio Araguaia; compreender a importância deste rio nos padrões intraespecíficos de estrutura e diversidade genética para diferentes espécies com diferentes características ecológicas; avaliar o potencial de diferentes metodologias para o estudo e monitorização da herpetofauna regional. Os nossos resultados revelam que a amostragem continuada e o uso de diferentes técnicas são essenciais para a obtenção de uma imagem precisa da diversidade da herpetofauna local. As comunidades locais de anfíbios e lagartos apresentaram maior riqueza específica na Área de Protecção Ambiental Bananal/Cantão (APABC), uma área tampão, do no Parque Estadual do Cantão (PEC), uma área de conservação estrita. A APABC é caracterizada por uma maior heterogeneidade de habitats e os nosso resultados corroboram a teoria da heterogeneidade espacial e resultados recentes que revelam uma maior diversidade de lagartos nas zonas interfluviais do Cerrado, do que nas matas de galeria. Os resultados aqui apresentados não corroboram a hipótese de que os ecótonos apresentam maior diversidade do que os biomas em redor. Os nossos resultados revelaram ainda que o Rio Araguaia afecta de forma diferente a estrutura genética de várias espécies de anfíbios e lagartos. Estas diferenças poderão estar relacionadas com a ecologia das espécies, nomeadamente com o uso de diferentes habitats, a vagilidade, ou a estratégia alimentar. Sugerimos que a gestão integração de diferentes unidades de conservação, com diferentes estatutos, podem ajudar a preservar melhor a biota regional.

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The increased capabilities (e.g., processing, storage) of portable devices along with the constant need of users to retrieve and send information have introduced a new form of communication. Users can seamlessly exchange data by means of opportunistic contacts among them and this is what characterizes the opportunistic networks (OppNets). OppNets allow users to communicate even when an end-to-end path may not exist between them. Since 2007, there has been a trend to improve the exchange of data by considering social similarity metrics. Social relationships, shared interests, and popularity are examples of such metrics that have been employed successfully: as users interact based on relationships and interests, this information can be used to decide on the best next forwarders of information. This Thesis work combines the features of today's devices found in the regular urban environment with the current social-awareness trend in the context of opportunistic routing. To achieve this goal, this work was divided into di erent tasks that map to a set of speci c objectives, leading to the following contributions: i) an up-to-date opportunistic routing taxonomy; ii) a universal evaluation framework that aids in devising and testing new routing proposals; iii) three social-aware utility functions that consider the dynamic user behavior and can be easily incorporated to other routing proposals; iv) two opportunistic routing proposals based on the users' daily routines and on the content traversing the network and interest of users in such content; and v) a structure analysis of the social-based network formed based on the approaches devised in this work.

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The development of computed tomography systems with energy resolving detectors is a current challenge in medical physics and biomedical engineering. A computed tomography system of this kind allows getting complementary informations relatively to conventional systems, that can help the medical diagnosis, being of great interest in medicine. The work described in this thesis is related to the development of a computed tomography system using micropattern gaseous detectors, which allow storing, simultaneously, information about the interaction position and the energy of each single photon that interacts with the detector. This kind of detectors has other advantages concerning the cost and characteristics of operation when compared with solid state detectors. Tomographic acquisitions were performed using a MicroHole & Strip Plate based detector, which allowed reconstructing cross-sectional images using energy windows, applying the energy weighting technique and performing multi-slice and tri-dimensional reconstructions. The contrast-to-noise ratio was improved by 31% by applying the energy weighting technique, comparing with the corresponding image obtained with the current medical systems. A prototype of a computed tomography with flexibility to change the detector was developed, making it possible to apply different detectors based on Thick-COBRA. Several images acquired with these detectors are presented and demonstrate their applicability in X-ray imaging. When operating in NeCH4, the detector allowed a charge gain of 8 104, an energy resolution of 20% (full width at half maximum at 8 keV), a count rate of 1 106 Hz/mm2, a very stable operation (gain fluctuations below 5%) and a spacial resolution of 1.2 mm for an energy photon of 3.6 keV. Operating the detector in pure Kr allowed increasing the detection efficiency and achieving a charge gain of 2 104, an energy resolution of 32% (full width at half maximum at 22 keV), a count rate of 1 105 Hz/mm2, very stable operation and a spatial resolution of 500 m. The software already existing in the group was improved and tools to correct geometric misalignments of the system were also developed. The reconstructions obtained after geometrical correction are free of artefacts due to the referred misalignments.

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The sustainable viticulture of a region passes, among other aspects, for maximizing the varieties potential minimizing subsequent interventions during winemaking, which should contribute to the production of quality wines maintaining their typicity and rationalizing costs. The detailed knowledge of each Appellation specificities, namely vineyard parcel (soil type and topographical peculiarities) and harvest climatic conditions is crucial for sustainability in this sector. Thus, in line with this current trend, the starting point for the development of this PhD thesis was to evaluate the oenological potential of different varieties cultivated throughout Bairrada Appellation (Portugal). During maturation several changes in grape varieties occur, namely berries become sweeter, less acidic, and they develop flavour, aroma and colour properties. The development of these characteristics is essential to define grapes oenological potential, i.e. to estimate the possibility of their usage to produce specific wines. A three years sampling plan was designed to evaluate the effect of harvest year and parcel characteristics on V. vinifera cv. Arinto, Bical, Sauvignon Blanc, Baga, Castelão, Touriga Nacional, and Sousão grapes composition. For each variety, 3 parcels with different characteristics were selected. Several physicochemical parameters were evaluated, during maturation: berry weight, pH, titratable acidity, sugar and phenolic contents, antiradical activity, and volatile composition (free fraction). Special attention was devoted to grapes at technologic maturity, since, besides these parameters, glycosidically-linked fraction was also considered. By using the results obtained at technologic maturity, a comprehensive approach was applied to identify the significance of harvest and parcel characteristics effects on each variety composition. Considering all the parameters under study, it may be highlighted some significant differences. According to the obtained results determined during maturation, it was possible to conclude that Arinto, Bical and Sauvignon Blanc grapes from parcels with clay-sandy and clay-calcareous soils have higher phenolic content and antiradical activity. Otherwise, Sauvignon Blanc presented similar volatile composition for grapes cultivated in the 3 parcels, while Arinto and Bical exhibited higher volatile content in grapes from claysandy and clay-calcareous soils. For Baga, Castelão and Touriga Nacional red varieties, grapes with higher phenolic content, antiradical activity, and volatile content were obtained from clayey and clay-calcareous soils. Furthermore, for Touriga Nacional, parcels altitude seems also to modulate grapes composition. Beyond parcel effect, harvest year conditions also influence grapes composition: 2011 harvest was related with lower phenolic and volatile contents, as well as lower antiradical activity.For grapes collected at technologic maturity, analysis of variance-simultaneous component analysis (ASCA) was applied combining all the parameters under study, in order to assess the influence of harvest and parcel characteristics on each variety oenological potential. The results obtained using this comprehensive approach is closely related with those observed during maturation and revealed that harvest was the main factor that influenced grapes composition (53% to 68% of the total data set variance) followed by parcel characteristics, explaining ca. 15-19% of the total data set variance. The oenological potential of each variety may be different from one parcel to another, i.e., clay-sandy and clay-calcareous related-environments seem to favour Arinto and Bical white grapes composition, but for the red varieties, grapes composition was favoured by clayey and clay-calcareous soils. Besides, also higher altitude seems to favour Touriga Nacional grapes composition. Sauvignon Blanc seems to be a variety well adapted to the different parcel characteristics. In order to go forward in the valuation of these varieties, the aroma properties of 6 monovarietal wines were studied based on an aroma network-approach, linking molecular data related to volatile composition and aroma data about the key odor active molecules. This approach allowed to identify different wine aroma properties and to infer about the consumer’s sensory perception. It was found that aroma properties differ from one wine variety to another: while Arinto and Sauvignon Blanc wine exhibited higher tree fruity, sweety and flowery aromas, related essentially with ester compounds and C13 norisoprenoids, the opposite was obtained for Bical wine, corroborating the aroma sensory perceptions of the trained panel. Sauvignon Blanc also exhibited higher toasted aromas (related with thiols, mainly with 2-methyl-3-furanthiol). Touriga Nacional red wine exhibited higher tree, tropical, and berry fruits notes (sensory described as sweet fruits), toasted and flowery aromas, while these are similar for the other red wines under study. Besides Portuguese Bairrada wines, this aroma network approach is a tool that can be used to explain the aroma properties of wines worldwide. The grape and wine data generated under the present PhD thesis, in the context of Bairrada Appellation, shows the unique character of each variety, and may be used by growers and wine producers as a support for decisionmaking based on objective criteria, increasing the sustainability in this sector. For instance, it is possible to take advantage of the natural resources and produce products with different characteristics obtained from the same variety, minimizing costs during the winemaking process.

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Tese dout., Engenharia electrónica e computação - Processamento de sinal, Universidade do Algarve, 2008