944 resultados para Delay in Diagnosis


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Objectivos: Neste estudo retrospectivo pretendeu-se determinar o impacto da tomografia computorizada na sobrevivência pós-cirúrgica do cão com carcinoma espinocelular na cavidade oral, comparativamente à radiografia. Enfatizando desta forma, a sua importância no diagnóstico, no planeamento cirúrgico e prognóstico. O segundo objectivo consistiu em determinar as características tomográficas dos carcinomas espinocelulares da cavidade oral em cães. Material e Métodos: Foram analisados 7 canídeos com diagnóstico de carcinoma espinocelular. Os critérios de inclusão foram: cães com carcinoma espinocelular diagnosticado por biópsia, exame imagiológico complementar (radiografia simples ou tomografia computorizada), elegibilidade para cirurgia, execução de tratamento cirúrgico e acompanhamento pós-cirúrgico durante 2 anos. Foi registada a idade, o sexo, a raça, a localização anatómica, o estadiamento T e N, as características radiográficas e tomográficas dos tumores, o tempo de recorrência e por fim o tempo de sobrevivência global descrito nos registos consultados. Procedeu-se também ao registo das variáveis das imagens radiográficas e tomográficas obtidas: definição das margens neoplásicas, presença ou ausência de reacção perióstea e de destruição de osso cortical adjacente, presença de deslocação dentária e de reabsorção dentária e densidade óssea local. Resultados: Nenhum dos meios imagiológicos permitiu uma visualização bem definida das margens neoplásicas. A nível da destruição de osso cortical adjacente, foi visível em 66,67% dos casos avaliados com radiografia e em todos os casos que foram avaliados com tomografia computorizada (100%). Foi visível reacção perióstea em 33,33% dos canídeos avaliados por radiografia e em nenhum dos avaliados por tomografia (0%). A densidade óssea local estava diminuída em todos os casos avaliados por radiografia simples ou por tomografia. A nível de reabsorção dentária estava presente em 33,33% dos avaliados por radiografia e em 25% dos avaliados por tomografia. Foi possível visualizar deslocação dentária em 66,67% dos avaliados por radiografia e em todos os avaliados por tomografia (100%). A nível de percentagem de casos com recorrência local, nenhum caso avaliado com radiografia recorreu e apenas 1 caso avaliado por tomografia recorreu em 289 dias. O tempo médio de sobrevivência foi superior no grupo dos avaliados com radiografia (1091,7 dias) relativamente ao grupo avaliado por tomografia (404 dias). Ao fim de 2 anos, 66,67% dos casos avaliados por radiografia estavam vivos e somente 25% dos casos avaliados com tomografia sobreviveram. Discussão/conclusão: Não foi possível determinar o impacto real dos dois meios de diagnóstico no prognóstico pós-cirúrgico do carcinoma espinocelular oral no cão, devido à reduzida amostra e aos tumores com pior prognóstico (por localização e estadiamento) terem sido remetidos para tomografia.

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The EU is in the process of negotiating its 2014-20 financial framework. Failure to reach an agreement would imply a delay in the preparation of the strategic plans each member state puts together to explain how it will use Structural and Cohesion Funds. Even if solutions are found – for example annual renewals of the budget based on the previous year's figures – there will be political and institutional costs. EU leaders have too often and too forcefully advocated the use of the EU budget for growth to be able to drop the idea without consequences. • The overwhelming attention paid to the size of the budget is misplaced. EU leaders should instead aim to make the EU budget more flexible, safeguard it from future political power struggles, and reinforce assessment of the impact of EU funded growth policies. • To improve flexibility a commitment device should be created that places the EU budget above continuous political disagreement. We suggest the creation of a European Growth Fund, on the basis of which the European Commission should be allowed to borrow on capital markets to anticipate pre-allocated EU expenditure, such as Structural and Cohesion Funds. Markets would thus be a factor in EU budget policymaking, with a potentially disciplining effect. Attaching conditionality to this type of disbursement appears legitimate, as capital delivered in this way is a form of assistance.

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The increase in coastal storm frequency and intensity expected under most climate change scenarios is likely to substantially modify beach configuration and associated habitats. This study aimed to analyze the impact of coastal storms on a nesting population of the endangered Piping Plover (Charadrius melodus melodus) in southeastern New Brunswick, Canada. Previous studies have shown that numbers of nesting Piping Plovers may increase following storms that create new nesting habitat at individual beaches. However, to our knowledge, no test of this pattern has been conducted over a regional scale. We hypothesized that Piping Plover abundance would increase after large coastal storms occurring during the nonbreeding season. However, we expected a delay in the colonization of newly created habitat owing to low-density populations, combined with high site fidelity of adults and high variability in survival rate of subadults. We tested this hypothesis using a 27-year (1986-2012) data set of Piping Plover abundance and productivity (nesting pairs and fledged young) collected at five sites in eastern New Brunswick. We identified 11 major storms that could potentially have modified Piping Plover habitat over the study period. The number of fledged young increased three years after a major storm, but the relationship was much weaker for the number of nesting pairs. These findings are consistent with the hypothesized increase in suitable habitat after coastal storms. Including storm occurrence with other factors influencing habitat quality will enhance Piping Plover conservation strategies.

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Recent developments in the fields of veterinary epidemiology and economics are critically reviewed and assessed. The impacts of recent technological developments in diagnosis, genetic characterisation, data processing and statistical analysis are evaluated. It is concluded that the acquisition and availability of data remains the principal constraint to the application of available techniques in veterinary epidemiology and economics, especially at population level. As more commercial producers use computerised management systems, the availability of data for analysis within herds is improving. However, consistency of recording and diagnosis remains problematic. Recent trends to the development of national livestock databases intended to provide reassurance to consumers of the safety and traceability of livestock products are potentially valuable sources of data that could lead to much more effective application of veterinary epidemiology and economics. These opportunities will be greatly enhanced if data from different sources, such as movement recording, official animal health programmes, quality assurance schemes, production recording and breed societies can be integrated. However, in order to realise such integrated databases, it will be necessary to provide absolute control of user access to guarantee data security and confidentiality. The potential applications of integrated livestock databases in analysis, modelling, decision-support, and providing management information for veterinary services and livestock producers are discussed. (c) 2004 Elsevier B.V. All rights reserved.

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Where users are interacting in a distributed virtual environment, the actions of each user must be observed by peers with sufficient consistency and within a limited delay so as not to be detrimental to the interaction. The consistency control issue may be split into three parts: update control; consistent enactment and evolution of events; and causal consistency. The delay in the presentation of events, termed latency, is primarily dependent on the network propagation delay and the consistency control algorithms. The latency induced by the consistency control algorithm, in particular causal ordering, is proportional to the number of participants. This paper describes how the effect of network delays may be reduced and introduces a scalable solution that provides sufficient consistency control while minimising its effect on latency. The principles described have been developed at Reading over the past five years. Similar principles are now emerging in the simulation community through the HLA standard. This paper attempts to validate the suggested principles within the schema of distributed simulation and virtual environments and to compare and contrast with those described by the HLA definition documents.

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A quasi-optical de-embedding technique for characterizing waveguides is demonstrated using wideband time-resolved terahertz spectroscopy. A transfer function representation is adopted for the description of the signal in the input and output port of the waveguides. The time domain responses were discretised and the waveguide transfer function was obtained through a parametric approach in the z-domain after describing the system with an ARX as well as with a state space model. Prior to the identification procedure, filtering was performed in the wavelet domain to minimize signal distortion and the noise propagating in the ARX and subspace models. The model identification procedure requires isolation of the phase delay in the structure and therefore the time-domain signatures must be firstly aligned with respect to each other before they are compared. An initial estimate of the number of propagating modes was provided by comparing the measured phase delay in the structure with theoretical calculations that take into account the physical dimensions of the waveguide. Models derived from measurements of THz transients in a precision WR-8 waveguide adjustable short will be presented.

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In a decision feedback equalizer (DFE), the structural parameters, including the decision delay, the feedforward filter (FFF), and feedback filter (FBF) lengths, must be carefully chosen, as they greatly influence the performance. Although the FBF length can be set as the channel memory, there is no closed-form expression for the FFF length and decision delay. In this letter, first we analytically show that the two-dimensional search for the optimum FFF length and decision delay can be simplified to a one-dimensional search and then describe a new adaptive DFE where the optimum structural parameters can be self-adapted.

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This paper investigates how to choose the optimum tap-length and decision delay for the decision feedback equalizer (DFE). Although the feedback filter length can be set as the channel memory, there is no closed-form expression for the feedforward filter length and decision delay. In this paper, first we analytically show that the two dimensional search for the optimum feedforward filter length and decision delay can be simplified to a one dimensional search, and then describe a new adaptive DFE where the optimum structural parameters can be self-adapted.

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An active pharmaceutical ingredient (API) was found to dissociate from the highly crystalline hydrochloride form to the amorphous free base form, with consequent alterations to tablet properties. Here, a wet granulation manufacturing process has been investigated using in situ Fourier transform (FT)-Raman spectroscopic analyses of granules and tablets prepared with different granulating fluids and under different manufacturing conditions. Dosage form stability under a range of storage stresses was also investigated. Despite the spectral similarities between the two drug forms, low levels of API dissociation could be quantified in the tablets; the technique allowed discrimination of around 4% of the API content as the amorphous free base (i.e. less than 1% of the tablet compression weight). API dissociation was shown to be promoted by extended exposure to moisture. Aqueous granulating fluids and manufacturing delays between granulation and drying stages and storage of the tablets in open conditions at 40◦C/75% relative humidity (RH) led to dissociation. In contrast, non-aqueous granulating fluids, with no delay in processing and storage of the tablets in either sealed containers or at lower temperature/humidity prevented detectable dissociation. It is concluded that appropriate manufacturing process and storage conditions for the finished product involved minimising exposure to moisture of the API. Analysis of the drug using FT-Raman spectroscopy allowed rapid optimisation of the process whilst offering quantitative molecular information concerning the dissociation of the drug salt to the amorphous free base form.

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In this paper we describe how to cope with the delays inherent in a real time control system for a steerable stereo head/eye platform. A purposive and reactive system requires the use of fast vision algorithms to provide the controller with the error signals to drive the platform. The time-critical implementation of these algorithms is necessary, not only to enable short latency reaction to real world events, but also to provide sufficiently high frequency results with small enough delays that controller remain stable. However, even with precise knowledge of that delay, nonlinearities in the plant make modelling of that plant impossible, thus precluding the use of a Smith Regulator. Moreover, the major delay in the system is in the feedback (image capture and vision processing) rather than feed forward (controller) loop. Delays ranging between 40msecs and 80msecs are common for the simple 2D processes, but might extend to several hundred milliseconds for more sophisticated 3D processes. The strategy presented gives precise control over the gaze direction of the cameras despite the lack of a priori knowledge of the delays involved. The resulting controller is shown to have a similar structure to the Smith Regulator, but with essential modifications.

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Isogenic mutants of Salmonella enteritidis defective for the elaboration of fimbrial types SEF14, SEF17, SEF21 and flagella were used to study the contribution these organelles made to colonization, invasion and lateral transfer in young chicks. The caecum, liver and spleen were colonized within 24 h following oral inoculation of 1-day-old chicks with 10(5) wild-type S. enteritidis strain LA5. However, for some mutants, the numbers of organisms recovered from internal organs was reduced significantly, particularly at 24 h post-inoculum, which supported the hypothesis that the organelles contribute to invasion and dissemination to internal organs. Specifically, mutations affecting SEF17, SEF21 and flagella contributed to a delay in colonization of the spleen, and those affecting SEF21 and flagella delayed colonization of the liver. Lower numbers of bacteria were recovered from the caecum with mutants deficient in elaboration of SEF21. Sentinel birds were colonized by LA5 or EAV40 (14(-), 17(-), 21(-), fla(-)) directly from the environment within 2 days, although a consistent slight delay was observed with the multiple mutant. Overall, our data suggest a collective role for SEF17, SEF21 and flagella, but not SEF14, in the early stages of colonization and invasion of young chicks by S. enteritidis, but these surface appendages appear unnecessary for colonization of birds from their immediate environment.

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The effect of spatial and temporal variations in the radiative damping rate on the response to an imposed forcing or diabatic heating is examined in a zonal-mean model of the middle atmosphere. Attention is restricted to the extratropics, where a linear approach is viable. It is found that regions with weak radiative damping rates are more sensitive in terms of temperature to the remote influence of the diabatic circulation. The delay in the response in such regions can mean that ‘downward’ control is not achieved on seasonal time-scales. A seasonal variation in the radiative damping rate modulates the evolution of the response and leaves a transient-like signature in the annual mean temperature field. Several idealized examples are considered, motivated by topical questions. It is found that wave drag outside the polar vortex can significantly affect the temperatures in its interior, so that high-latitude, high-altitude gravity-wave drag is not the only mechanism for warming the southern hemisphere polar vortex. Diabatic mass transport through the 100 hPa surface is found to lag the seasonal evolution of the wave drag that drives the transport, and thus cannot be considered to be in the downward control regime. On the other hand, the seasonal variation of the radiative damping rate is found to make only a weak contribution to the annual mean temperature increase that has been observed above the ozone hole. Copyright © 2002 Royal Meteorological Society.

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Quantitative simulations of the global-scale benefits of climate change mitigation are presented, using a harmonised, self-consistent approach based on a single set of climate change scenarios. The approach draws on a synthesis of output from both physically-based and economics-based models, and incorporates uncertainty analyses. Previous studies have projected global and regional climate change and its impacts over the 21st century but have generally focused on analysis of business-as-usual scenarios, with no explicit mitigation policy included. This study finds that both the economics-based and physically-based models indicate that early, stringent mitigation would avoid a large proportion of the impacts of climate change projected for the 2080s. However, it also shows that not all the impacts can now be avoided, so that adaptation would also therefore be needed to avoid some of the potential damage. Delay in mitigation substantially reduces the percentage of impacts that can be avoided, providing strong new quantitative evidence for the need for stringent and prompt global mitigation action on greenhouse gas emissions, combined with effective adaptation, if large, widespread climate change impacts are to be avoided. Energy technology models suggest that such stringent and prompt mitigation action is technologically feasible, although the estimated costs vary depending on the specific modelling approach and assumptions.

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Money’s ability to enhance memory has received increased attention in recent research. However, previous studies have not directly addressed the time-dependent nature of monetary effects on memory, which are suggested to exist by research in cognitive neuroscience, and the possible detrimental effects of monetary rewards on learning interesting material, as indicated by studies in motivational psychology. By utilizing a trivia question paradigm, the current study incorporated these perspectives and examined the effect of monetary rewards on immediate and delayed memory performance for answers to uninteresting and interesting questions. Results showed that monetary rewards promote memory performance only after a delay. In addition, the memory enhancement effect of monetary rewards was only observed for uninteresting questions. These results are consistent with both the hippocampus-dependent memory consolidation model of reward learning and previous findings documenting the ineffectiveness of monetary rewards on tasks that have intrinsic value.

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Neural differentiation of embryonic stem cells (ESCs) requires coordinated repression of the pluripotency regulatory program and reciprocal activation of the neurogenic regulatory program. Upon neural induction, ESCs rapidly repress expression of pluripotency genes followed by staged activation of neural progenitor and differentiated neuronal and glial genes. The transcriptional factors that underlie maintenance of pluripotency are partially characterized whereas those underlying neural induction are much less explored, and the factors that coordinate these two developmental programs are completely unknown. One transcription factor, REST (repressor element 1 silencing transcription factor), has been linked with terminal differentiation of neural progenitors and more recently, and controversially, with control of pluripotency. Here, we show that in the absence of REST, coordination of pluripotency and neural induction is lost and there is a resultant delay in repression of pluripotency genes and a precocious activation of both neural progenitor and differentiated neuronal and glial genes. Furthermore, we show that REST is not required for production of radial glia-like progenitors but is required for their subsequent maintenance and differentiation into neurons, oligodendrocytes, and astrocytes. We propose that REST acts as a regulatory hub that coordinates timely repression of pluripotency with neural induction and neural differentiation.