128 resultados para Distinctive features

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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The complete spectrum of eigenwaves including surface plasmon polaritons (SPP), dynamic (bulk) and complex waves in the layered structures containing semiconductor and metallic films has been explored. The effects of loss, geometry and the parameters of dielectric layers on the eigenmode spectrum and, particularly, on the SPP modes have been analysed using both the asymptotic and rigorous numerical solutions of the full-wave dispersion equation. The field and Poynting vector distributions have been examined to identify the modes and elucidate their properties. It has been shown that losses and dispersion of permittivity qualitatively alter the spectral content and the eigenwave properties. The SPP counter-directional power fluxes in the film and surrounding dielectrics have been attributed to vortices of power flow, which are responsible for the distinctive features of SPP modes. It has been demonstrated for the first time that the maximal attainable slow-wave factor of the SPP modes guided by thin Au films at optical frequencies is capped not by losses but the frequency dispersion of the actual Au permittivity. © 2009 EDP Sciences.

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Although overshadowed by the ‘big bang’ enlargement of 2004, the accession of Bulgaria and Romania to the EU in 2007 was more than simply a ‘coda’ enlargement. It had its own distinctive features and provides important insights into how the EU’s handling of enlargement is evolving. It established a number of interesting and potentially significant precedents and provided timely reminders of how important political and public opinion can be for ratification. Examination of the period from negotiating the terms of membership to the actual accession of the two applicants underlines the dynamic and increasingly uncertain nature of the EU enlargement process.

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Over the years, build-operate-transfer (BOT) has continuously attracted research interests. Many studies on BOT have been carried out. Variations of BOT such as build-own-operate-transfer and build-own-operate have also been reported in some relevant publications. However, few investigations thus far have been conducted for transfer-operate-transfer (TOT). Therefore, there is a knowledge gap in this particular field. TOT is a new model that is suitable for existing infrastructure and public utility projects formerly funded by the governments and currently operated by state-owned enterprises. It refers to the transfer of a running public project to a foreign business or domestic private entity. Based on four case studies carried out in the Chinese water supply industry, this paper examines why there is an increasing need for TOT projects and identifies the distinctive features of TOT practice in China. This is followed by an introduction of a framework of critical success factors (CSFs) for TOT projects. The most important factors include project profitability, asset quality, fair risk allocation, competitive tendering, internal coordination within government, employment of professional advisors, corporate governance, and government supervision. The identification of CSFs provides a useful guidance to project parties planning to participate in TOT practice.


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An algorithm has been developed for a Public Access Defibrillator which utilizes distinctive features from the impedance cardiogram (ICG) recorded via defibrillator pads to advise both lay users and minimally trained bystanders to ensure CPR effectiveness. Following ethical approval, data were collected and marked. CPR was administered by trained personnel. 211 cases were gathered and the training set included 106 cases. A retrospective analysis was carried out of simultaneously recorded ECG and ICG. The speed of compressions was calculated by counting the outstanding waves in the ICG during CPR. Also if the base-to-peak amplitude of the ICG is greater than a minimum threshold, the corresponding compressions were classified as being applied with adequate force. For the validation set, adequate speed was detected with 91.45% sensitivity and 96.27% specificity (79826s) and adequate force with 99.94% sensitivity and 97.91% specificity (91973s). © 2011 CCAL.

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The novel concept and architecture of the vertically stacked multistage circulator with a single source of dc magnetic bias has been proposed. The distinctive features of the new arrangement are discussed and the main aspects of the circulator design, including the dc magnetic bias and concurrent thermal stabilization of multiple junctions, are presented. The experimental prototype of the VHF stacked double isolator exhibits low loss, high isolation, excellent thermal stability and the high power handling capability. The proposed class of multistage circulators can significantly increase dynamic range of the transceivers for the RF front-end of the emerging white space UHF/VHF applications. © 2012 IEEE.

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We propose a realistic scheme for measuring the micromaser linewidth by monitoring the phase diffusion dynamics of the cavity field. Our strategy consists of exciting an initial coherent state with the same photon number distribution as the micromaser steady-state field, singling out a purely diffusive process in the system dynamics. After the injection of a counterfield, measurements of the population statistics of a probe atom allow us to derive the micromaser linewidth in all ranges of the relevant parameters, establishing experimentally the distinctive features of the micromaser spectrum due to the discreteness of the electromagnetic field.

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This chapter explores the ways that adopted children and their birth parents can remain co-present following adoption. It focuses specifically on public adoption of children who have been in the care of child welfare services, and draws on adoptive parents’ accounts of their experiences of adoption openness. The distinctive features of co-presence between children and their birth parents after adoption are: that it is mediated by negotiated contact agreements and through on-going adoptive family practices; and that it is occasional, with its infrequency displaying the status and significance of birth relationships. Physical co-presence can in some cases be achieved through face-to-face contact meetings, however, even when this not possible, birth parents can be present in the hearts and minds of the adoptive family, constituting a form of imagined co-presence. The chapter explores how adopters achieve, delimit and mediate imagined and physical co-presence between their child and birth parent and concludes by considering the emergence of virtual co-presence via online social media.

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We performed an immunogenetic analysis of 345 IGHV-IGHD-IGHJ rearrangements from 337 cases with primary splenic small B-cell lymphomas of marginal-zone origin. Three immunoglobulin (IG) heavy variable (IGHV) genes accounted for 45.8% of the cases (IGHV1-2, 24.9%; IGHV4-34, 12.8%; IGHV3-23, 8.1%). Particularly for the IGHV1-2 gene, strong biases were evident regarding utilization of different alleles, with 79/86 rearrangements (92%) using allele (*)04. Among cases more stringently classified as splenic marginal-zone lymphoma (SMZL) thanks to the availability of splenic histopathological specimens, the frequency of IGHV1-2(*)04 peaked at 31%. The IGHV1-2(*)04 rearrangements carried significantly longer complementarity-determining region-3 (CDR3) than all other cases and showed biased IGHD gene usage, leading to CDR3s with common motifs. The great majority of analyzed rearrangements (299/345, 86.7%) carried IGHV genes with some impact of somatic hypermutation, from minimal to pronounced. Noticeably, 75/79 (95%) IGHV1-2(*)04 rearrangements were mutated; however, they mostly (56/75 cases; 74.6%) carried few mutations (97-99.9% germline identity) of conservative nature and restricted distribution. These distinctive features of the IG receptors indicate selection by (super)antigenic element(s) in the pathogenesis of SMZL. Furthermore, they raise the possibility that certain SMZL subtypes could derive from progenitor populations adapted to particular antigenic challenges through selection of VH domain specificities, in particular the IGHV1-2(*)04 allele.

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Studies suggest that activation of phosphoinositide 3-kinase-Akt may protect against neuronal cell death in Alzheimer's disease (AD). Here, however, we provide evidence of increased Akt activation, and hyperphosphorylation of critical Akt substrates in AD brain, which link to AD pathogenesis, suggesting that treatments aiming to activate the pathway in AD need to be considered carefully. A different distribution of Akt and phospho-Akt was detected in AD temporal cortex neurons compared with control neurons, with increased levels of active phosphorylated-Akt in particulate fractions, and significant decreases in Akt levels in AD cytosolic fractions, causing increased activation of Akt (phosphorylated-Akt/total Akt ratio) in AD. In concordance, significant increases in the levels of phosphorylation of total Akt substrates, including: GSK3ßSer9, tauSer214, mTORSer2448, and decreased levels of the Akt target, p27kip1, were found in AD temporal cortex compared with controls. A significant loss and altered distribution of the major negative regulator of Akt, PTEN (phosphatase and tensin homologue deleted on chromosome 10), was also detected in AD neurons. Loss of phosphorylated-Akt and PTEN-containing neurons were found in hippocampal CA1 at end stages of AD. Taken together, these results support a potential role for aberrant control of Akt and PTEN signalling in AD.

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OBJECTIVE: To investigate the influence of culture with G-CSF GM-CSF and TNFalpha on neutrophil apoptosis, comparing neutrophils from SLE patients with rheumatoid arthritis (RA) patients and healthy control subjects. METHODS: Neutrophils were isolated from SLE (n= 10), RA (n= 10) and healthy control subjects (n= 10), and cultured with two different concentrations of G-CSF, GM-CSF and TNFalpha. Proportion of apoptotic neutrophils at T=0, T=2hrs and T=24hrs was measured using FITC-labelled annexinV and flow cytometry. RESULTS: Significantly more neutrophils were apoptotic at T=0 in the SLE subjects than in the other groups (median, range--Control 3.5% (0.3-7.9) SLE 9.5% (2.9-29.1) RA 3.0% (0.4-23.0) p

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Background Interferon ? receptor 1 (IFN? R1) deficiency is a primary immunodeficiency with allelic dominant and recessive mutations characterised clinically by severe infections with mycobacteria. We aimed to compare the clinical features of recessive and dominant IFN?R1 deficiencies. Methods We obtained data from a large cohort of patients worldwide. We assessed these people by medical histories, records, and genetic and immunological studies. Data were abstracted onto a standard form. Findings We identified 22 patients with recessive complete IFN?R1 deficiency and 38 with dominant partial deficiency. BCG and environmental mycobacteria were the most frequent pathogens. In recessive patients, 17 (77%) had environmental mycobacterial disease and all nine BCG-vaccinated patients had BCG disease. In dominant patients, 30 (79%) had environmental mycobacterial disease and 11 (73%) of 15 BCG-vaccinated patients had BCG disease. Compared with dominant patients, those with recessive deficiency were younger at onset of first environmental mycobacterial disease (mean 3·1 years [SD 2·5] vs 13·4 years [14·3], p=0·001), had more mycobacterial disease episodes (19 vs 8 per 100 person-years of observation, p=0·0001), had more severe mycobacterial disease (mean number of organs infected by Mycobacterium avium complex 4·1 [SD 0·8] vs 2·0 [1·1], p=0·004), had shorter mean disease-free intervals (1·6 years [SD 1·4] vs 7·2 years [7·6], p

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Grey Level Co-occurrence Matrix (GLCM), one of the best known tool for texture analysis, estimates image properties related to second-order statistics. These image properties commonly known as Haralick texture features can be used for image classification, image segmentation, and remote sensing applications. However, their computations are highly intensive especially for very large images such as medical ones. Therefore, methods to accelerate their computations are highly desired. This paper proposes the use of programmable hardware to accelerate the calculation of GLCM and Haralick texture features. Further, as an example of the speedup offered by programmable logic, a multispectral computer vision system for automatic diagnosis of prostatic cancer has been implemented. The performance is then compared against a microprocessor based solution.