44 resultados para Activated partial thromboplastin time (APTT)
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OBJECTIVES: The aims of this study were to conduct a randomised controlled clinical trial (RCT) of partially dentate older adults comparing functionally orientated treatment based on the SDA concept with conventional treatment using RPDs to replace missing natural teeth. The two treatment strategies were evaluated according to their impact on nutritional status measured using haematological biomarkers.
METHODS: A randomised controlled clinical trial (RCT) was conducted of partially dentate patients aged 65 years and older (Trial Registration no. ISRCTN26302774). Each patient provided haematological samples which were screened for biochemical markers of nutritional status. Each sample was tested in Cork University Hospital for serum Albumin, serum Cholesterol, Ferritin, Folate, Vitamin B12 and 25-hydroxycholecalciferol (Vitamin D).
RESULTS: A mixed model analysis of covariance (ANCOVA) indicated that for Vitamin B12 (p=0.9392), serum Folate (p=0.5827), Ferritin (p=0.6964), Albumin (p=0.8179), Serum Total Cholesterol (p=0.3670) and Vitamin D (p=0.7666) there were no statistically significant differences recorded between the two treatment groups. According to the mixed model analysis of covariance (ANCOVA) for Vitamin D there was a significant difference between levels recorded at post-operative time points after treatment intervention (p=0.0470). There was an increase of 7% in 25-hydroxycholecalciferol levels recorded at 6 months compared to baseline (p=0.0172). There was no further change in recorded levels at 12 months (p=0.6482) and these increases were similar within the two treatment groups (p>0.05).
CONCLUSIONS: The only measure which illustrated consistent significant improvements in nutritional status for either group were Vitamin D levels. However no significant difference was recorded between the two treatment groups.
CLINICAL SIGNIFICANCE: Functionally orientated prosthodontic rehabilitation for partially dentate older patients was no worse than conventional removable partial dentures in terms of impact on nutritional status.
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Shoeprint evidence collected from crime scenes can play an important role in forensic investigations. Usually, the analysis of shoeprints is carried out manually and is based on human expertise and knowledge. As well as being error prone, such a manual process can also be time consuming; thus affecting the usability and suitability of shoeprint evidence in a court of law. Thus, an automatic system for classification and retrieval of shoeprints has the potential to be a valuable tool. This paper presents a solution for the automatic retrieval of shoeprints which is considerably more robust than existing solutions in the presence of geometric distortions such as scale, rotation and scale distortions. It addresses the issue of classifying partial shoeprints in the presence of rotation, scale and noise distortions and relies on the use of two local point-of-interest detectors whose matching scores are combined. In this work, multiscale Harris and Hessian detectors are used to select corners and blob-like structures in a scale-space representation for scale invariance, while Scale Invariant Feature Transform (SIFT) descriptor is employed to achieve rotation invariance. The proposed technique is based on combining the matching scores of the two detectors at the score level. Our evaluation has shown that it outperforms both detectors in most of our extended experiments when retrieving partial shoeprints with geometric distortions, and is clearly better than similar work published in the literature. We also demonstrate improved performance in the face of wear and tear. As matter of fact, whilst the proposed work outperforms similar algorithms in the literature, it is shown that achieving good retrieval performance is not constrained by acquiring a full print from a scene of crime as a partial print can still be used to attain comparable retrieval results to those of using the full print. This gives crime investigators more flexibility is choosing the parts of a print to search for in a database of footwear.
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This paper proposes a new thermography-based maximum power point tracking (MPPT) scheme to address photovoltaic (PV) partial shading faults. Solar power generation utilizes a large number of PV cells connected in series and in parallel in an array, and that are physically distributed across a large field. When a PV module is faulted or partial shading occurs, the PV system sees a nonuniform distribution of generated electrical power and thermal profile, and the generation of multiple maximum power points (MPPs). If left untreated, this reduces the overall power generation and severe faults may propagate, resulting in damage to the system. In this paper, a thermal camera is employed for fault detection and a new MPPT scheme is developed to alter the operating point to match an optimized MPP. Extensive data mining is conducted on the images from the thermal camera in order to locate global MPPs. Based on this, a virtual MPPT is set out to find the global MPP. This can reduce MPPT time and be used to calculate the MPP reference voltage. Finally, the proposed methodology is experimentally implemented and validated by tests on a 600-W PV array.
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We have obtained H$\alpha$ high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamic Observatory (SDO) and the {\it Hinode} ExtremeUltraviolet Imaging Spectrometer (EIS). The H$\alpha$ observations were conducted on 11 February 2012 with the Hydrogen-Alpha Rapid Dynamics Camera (HARDcam) instrument at the National Solar Observatory's Dunn Solar Telescope. Our H$\alpha$ observations found large downflows of chromospheric material returning from coronal heights following a failed prominence eruption. We have detected several large condensations ("blobs") returning to the solar surface at velocities of $\approx$200 km s$^{-1}$ in both H$\alpha$ and several SDO AIA band passes. The average derived size of these "blobs" in H$\alpha$ is 500 by 3000 km$^2$ in the directions perpendicular and parallel to the direction of travel, respectively. A comparison of our "blob" widths to those found from coronal rain, indicate there are additional smaller, unresolved "blobs" in agreement with previous studies and recent numerical simulations. Our observed velocities and decelerations of the "blobs" in both H$\alpha$ and SDO bands are less than those expected for gravitational free-fall and imply additional magnetic or gas pressure impeding the flow. We derived a kinetic energy $\approx$2 orders of magnitude lower for the main eruption than a typical CME, which may explain its partial nature.
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Differential equations are often directly solvable by analytical means only in their one dimensional version. Partial differential equations are generally not solvable by analytical means in two and three dimensions, with the exception of few special cases. In all other cases, numerical approximation methods need to be utilized. One of the most popular methods is the finite element method. The main areas of focus, here, are the Poisson heat equation and the plate bending equation. The purpose of this paper is to provide a quick walkthrough of the various approaches that the authors followed in pursuit of creating optimal solvers, accelerated with the use of graphical processing units, and comparing them in terms of accuracy and time efficiency with existing or self-made non-accelerated solvers.
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Game-theoretic security resource allocation problems have generated significant interest in the area of designing and developing security systems. These approaches traditionally utilize the Stackelberg game model for security resource scheduling in order to improve the protection of critical assets. The basic assumption in Stackelberg games is that a defender will act first, then an attacker will choose their best response after observing the defender’s strategy commitment (e.g., protecting a specific asset). Thus, it requires an attacker’s full or partial observation of a defender’s strategy. This assumption is unrealistic in real-time threat recognition and prevention. In this paper, we propose a new solution concept (i.e., a method to predict how a game will be played) for deriving the defender’s optimal strategy based on the principle of acceptable costs of minimax regret. Moreover, we demonstrate the advantages of this solution concept by analyzing its properties.
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The growth of the construction industry worldwide poses a serious concern on the sustainability of the building material production chain, mainly due to the carbon emissions related to the production of Portland cement. On the other hand, valuable materials from waste streams, particularly from the metallurgical industry, are not used at their full potential. Alkali activated concrete (AAC) has emerged in the last years as a promising alternative to traditional Portland cement based concrete for some applications. However, despite showing remarkable strength and durability potential, its utilisation is not widespread, mainly due to the lack of broadly accepted standards for the selection of suitable mix recipes fulfilling design requirements, in particular workability, setting time and strength. In this paper, a contribution towards the design development of AAC synthetized from pulverised fuel ash (60%) and ground granulated blast furnace slag (40%) activated with a solution of sodium hydroxide and sodium silicate is proposed. Results from a first batch of mixes indicated that water content influences the setting time and that paste content is a key parameter for controlling strength development and workability. The investigation indicated that, for the given raw materials and activator compositions, a minimum water to solid (w/s) ratio of 0.37 was needed for an initial setting time of about 1 hour. Further work with paste content in the range of 30% to 33% determined the relationship between workability and strength development and w/s ratio and paste content. Strengths in the range of 50 - 60 MPa were achieved.
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Alkali activated binders, based on ash and slag, also known as geopolymers, can play a key role in reducing the carbon footprint of the construction sector by replacing ordinary Portland cement in some concretes. Since 1970s, research effort has been ongoing in many research institutions. In this study, pulverized fuel ash (pfa) from a UK power plant, ground granulated blast furnace slag (ggbs) and combinations of the two have been investigated as geopolymer binders for concrete applications. Activators used were sodium hydroxide and sodium silicate solutions. Mortars with sand/binder ratio of 2.75 with several pfa and ggbs combinations have been mixed and tested. The optimization of alkali dosage (defined as the Na2O/binder mass ratio) and modulus (defined as the Na2O/SiO2 mass ratio) resulted in strengths in excess of 70 MPa for tested mortars. Setting time and workability have been considered for the identification of the best combination of pfa/ggbs and alkali activator dosage for different precast concrete products. Geopolymer concrete building blocks have been replicated in laboratory and a real scale factory trial has been successfully carried out. Ongoing microstructural characterization is aiming to identify reaction products arising from pfa/ggbs combinations.
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Rab5-dependent endosome fusion is sensitive to the phosphoinositide 3-kinase inhibitor, wortmannin. It has been proposed that phosphoinositide 3-kinase activity may be required for activation of rab5 by influencing its nucleotide cycle such as to promote its active GTP state. In this report we demonstrate that endosome fusion remains sensitive to wortmannin despite preloading of endosomes with stimulatory levels of a GTPase-defective mutant rab5(Q79L) or of a xanthosine triphosphate-binding mutant, rab5(D136N), in the presence of the nonhydrolysable analogue XTPgammaS. These results suggest that activation of rab5 cannot be the principal function of the wortmannin-sensitive factor on the endosome fusion pathway. This result is extrapolated to all GTPases by demonstrating that endosome fusion remains wortmannin sensitive despite prior incubation with the nonhydrolysable nucleotide analogue GTPgammaS. Consistent with these results, direct measurement of clathrin-coated vesicle-stimulated nucleotide dissociation from exogenous rab5 was insensitive to the presence of wortmannin. A large excess of rab5(Q79L), beyond levels required for maximal stimulation of the fusion assay, afforded protection against wortmannin inhibition, and partial protection was also observed with an excess of wild-type rab5 independent of GTPgammaS.
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Reasoning that is deliberative and reflective often requires the inhibition of intuitive responses. The Cognitive Reflection Test (CRT) is designed to assess people’s ability to suppress incorrect heuristic responses in favour of deliberation. Correct responding on the CRT predicts performance on a range of tasks in which intuitive processes lead to incorrect responses, suggesting indirectly that CRT performance is related to cognitive control. Yet little is known about the cognitive processes underlying performance on the CRT. In the current research, we employed a novel mouse tracking mjavascript:void(0);ethodology to capture the time-course of reasoning on the CRT. Analysis of mouse cursor trajectories revealed that participants were initially drawn towards the incorrect (i.e., intuitive) option even when the correct (deliberative) option was ultimately chosen. Conversely, participants were not attracted to the correct option when they ultimately chose the incorrect intuitive one. We conclude that intuitive processes are activated automatically on the CRT and must be inhibited in order to respond correctly. When participants responded intuitively, there was no evidence that deliberative reasoning had become engaged.
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Studies have been carried out to recognize individuals from a frontal view using their gait patterns. In previous work, gait sequences were captured using either single or stereo RGB camera systems or the Kinect 1.0 camera system. In this research, we used a new frontal view gait recognition method using a laser based Time of Flight (ToF) camera. In addition to the new gait data set, other contributions include enhancement of the silhouette segmentation, gait cycle estimation and gait image representations. We propose four new gait image representations namely Gait Depth Energy Image (GDE), Partial GDE (PGDE), Discrete Cosine Transform GDE (DGDE) and Partial DGDE (PDGDE). The experimental results show that all the proposed gait image representations produce better accuracy than the previous methods. In addition, we have also developed Fusion GDEs (FGDEs) which achieve better overall accuracy and outperform the previous methods.
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We have measured mass spectra for positive ions for low-energy electron impact on thymine using a reflectron time-of-flight mass spectrometer. Using computer controlled data acquisition, mass spectra have been acquired for electron impact energies up to 100 eV in steps of 0.5 eV. Ion yield curves for most of the fragment ions have been determined by fitting groups of adjacent peaks in the mass spectra with sequences of normalized Gaussians. The ion yield curves have been normalized by comparing the sum of the ion yields to the average of calculated total ionization cross sections. Appearance energies have been determined. The nearly equal appearance energies of 83 u and 55 u observed in the present work strongly indicate that near threshold the 55 u ion is formed directly by the breakage of two bonds in the ring, rather than from a successive loss of HNCO and CO from the parent ion. Likewise 54 u is not formed by CO loss from 82 u. The appearance energies are in a number of cases consistent with the loss of one or more hydrogen atoms from a heavier fragment, but 70 u is not formed by hydrogen loss from 71 u.
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An anthraquinone dye, Remazol brilliant blue R, RBBR, is used to create an indicator which can function as: (i) a UV dosimeter, (ii) an O2 indicator and (iii) a ‘Consume within’ indicator, CWI, for fresh, refrigerated foods. The dye is encapsulated in an ink containing a polymer, glycerol and a UV-activated semiconductor photocatalyst, titanium dioxide. When cast as a film, the dye is readily reduced by the TiO2 photocatalyst nanoparticles, thereby changing the colour of the film from blue to yellow, via a transitional green colour. The RBBR indicator is appropriately formulated, and covered with a film of Sellotape, which acts as an O2 barrier, so as to act as a sunburn warning indicator for people with skin type II. In the absence of the layer of Sellotape the RBBR indicator is used as an, albeit slow, sensor for measuring ambient levels of O2. Finally, by keeping the Sellotape layer, a UV-activated, yellow-coloured, RBBR indicator film is found to take ca. 42 h at 5 °C in ambient air to attain a green colour, and, on this basis, it is demonstrated as a possible CWI for refrigerated fresh foods.
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This work investigates the production of activated lignin-chitosan extruded (ALiCE) pellets with controlled particle size distribution (almost spherical: dp ~500‒1000µm) for efficient methylene blue adsorption. The novel preparation method employed in this study successfully produced activated lignin-chitosan pellets. Structural and morphological characterizations were performed using BET, FTIR and SEM-EDX analyses. The influence of contact time, solution pH, ionic strength, initial adsorbate concentration and desorption studies was investigated. The experimental data fitted well with the Langmuir isotherm (R2 = 0.997), yielding a maximum adsorption capacity of 36.25mg/g. The kinetic data indicated that methylene blue (MB) adsorption onto ALiCE can be represented by the pseudo second-order-model with intraparticle processes initially controlling the process of MB adsorption. Overall, these results indicate that the novel ALiCE offers great potential for removing cationic organic pollutants from rivers and streams.