297 resultados para 13368-008
Resumo:
Control of biospecimen quality that is linked to processing is one of the goals of biospecimen science. Consensus is lacking, however, regarding optimal sample quality-control (QC) tools (ie, markers and assays). The aim of this review was to identify QC tools, both for fluid and solid-tissue samples, based on a comprehensive and critical literature review. The most readily applicable tools are those with a known threshold for the preanalytical variation and a known reference range for the QC analyte. Only a few meaningful markers were identified that meet these criteria, such as CD40L for assessing serum exposure at high temperatures and VEGF for assessing serum freeze-thawing. To fully assess biospecimen quality, multiple QC markers are needed. Here we present the most promising biospecimen QC tools that were identified.
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Laboratory-based studies of human dietary behaviour benefit from highly controlled conditions; however, this approach can lack ecological validity. Identifying a reliable method to capture and quantify natural dietary behaviours represents an important challenge for researchers. In this study, we scrutinised cafeteria-style meals in the ‘Restaurant of the Future.’ Self-selected meals were weighed and photographed, both before and after consumption. Using standard portions of the same foods, these images were independently coded to produce accurate and reliable estimates of (i) initial self-served portions, and (ii) food remaining at the end of the meal. Plate cleaning was extremely common; in 86% of meals at least 90% of self-selected calories were consumed. Males ate a greater proportion of their self-selected meals than did females. Finally, when participants visited the restaurant more than once, the correspondence between selected portions was better predicted by the weight of the meal than by its energy content. These findings illustrate the potential benefits of meal photography in this context. However, they also highlight significant limitations, in particular, the need to exclude large amounts of data when one food obscures another.
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In this paper we demonstrate how to monitor a smartphone running Symbian operating system and Windows Mobile in order to extract features for anomaly detection. These features are sent to a remote server because running a complex intrusion detection system on this kind of mobile device still is not feasible due to capability and hardware limitations. We give examples on how to compute relevant features and introduce the top ten applications used by mobile phone users based on a study in 2005. The usage of these applications is recorded by a monitoring client and visualized. Additionally, monitoring results of public and self-written malwares are shown. For improving monitoring client performance, Principal Component Analysis was applied which lead to a decrease of about 80 of the amount of monitored features.
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Modelling video sequences by subspaces has recently shown promise for recognising human actions. Subspaces are able to accommodate the effects of various image variations and can capture the dynamic properties of actions. Subspaces form a non-Euclidean and curved Riemannian manifold known as a Grassmann manifold. Inference on manifold spaces usually is achieved by embedding the manifolds in higher dimensional Euclidean spaces. In this paper, we instead propose to embed the Grassmann manifolds into reproducing kernel Hilbert spaces and then tackle the problem of discriminant analysis on such manifolds. To achieve efficient machinery, we propose graph-based local discriminant analysis that utilises within-class and between-class similarity graphs to characterise intra-class compactness and inter-class separability, respectively. Experiments on KTH, UCF Sports, and Ballet datasets show that the proposed approach obtains marked improvements in discrimination accuracy in comparison to several state-of-the-art methods, such as the kernel version of affine hull image-set distance, tensor canonical correlation analysis, spatial-temporal words and hierarchy of discriminative space-time neighbourhood features.
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This paper investigates the response of multi-storey structures under simulated earthquake loads with friction dampers, viscoelastic dampers and combined friction-viscoelastic damping devices strategically located within shear walls. Consequently, evaluations are made as to how the damping systems affect the seismic response of these structures with respect to deflections and accelerations. In particular, this paper concentrates on the effects of damper types, configurations and their locations within the cut-outs of shear walls. The initial stiffness of the cut out section of the shear wall is removed and replaced by the stiffness and damping of the device. Influence of parameters of damper properties such as stiffness, damping coefficient, location, configuration and size are studied and evaluated using results obtained under several different earthquake scenarios. Structural models with cut outs at different heights are treated in order to establish the effectiveness of the dampers and their optimal placement. This conceptual study has demonstrated the feasibility of mitigating the seismic response of building structures by using embedded dampers.
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We have analyzed a frondelite mineral sample from the Cigana mine, located in the municipality of Conselheiro Pena, a well-known pegmatite in Brazil. In the Cigana pegmatite, secondary phosphates, namely eosphorite, fairfieldite, fluorapatite, frondelite, gormanite, hureaulite, lithiophilite, reddingite and vivianite are common minerals in miarolitic cavities and in massive blocks after triphylite. The chemical formula was determined as (Mn0.68, Fe0.32)(Fe3+)3,72(PO4)3.17(OH)4.99. The structure of the mineral was assessed using vibrational spectroscopy. Bands attributed to the stretching and bending modes of PO4 3- and HOPO3 3- units were identified. The observation of multiple bands supports the concept of symmetry reduction of the phosphate anion in the frondelite structure. Sharp Raman and infrared bands at 3581 cm−1 is assigned to the OH stretching vibration. Broad Raman bands at 3063, 3529 and 3365 cm−1 are attributed to water stretching vibrational modes.
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Recent years have seen an increased uptake of business process management technology in industries. This has resulted in organizations trying to manage large collections of business process models. One of the challenges facing these organizations concerns the retrieval of models from large business process model repositories. For example, in some cases new process models may be derived from existing models, thus finding these models and adapting them may be more effective and less error-prone than developing them from scratch. Since process model repositories may be large, query evaluation may be time consuming. Hence, we investigate the use of indexes to speed up this evaluation process. To make our approach more applicable, we consider the semantic similarity between labels. Experiments are conducted to demonstrate that our approach is efficient.
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This study uses borehole geophysical log data of sonic velocity and electrical resistivity to estimate permeability in sandstones in the northern Galilee Basin, Queensland. The prior estimates of permeability are calculated according to the deterministic log–log linear empirical correlations between electrical resistivity and measured permeability. Both negative and positive relationships are influenced by the clay content. The prior estimates of permeability are updated in a Bayesian framework for three boreholes using both the cokriging (CK) method and a normal linear regression (NLR) approach to infer the likelihood function. The results show that the mean permeability estimated from the CK-based Bayesian method is in better agreement with the measured permeability when a fairly apparent linear relationship exists between the logarithm of permeability and sonic velocity. In contrast, the NLR-based Bayesian approach gives better estimates of permeability for boreholes where no linear relationship exists between logarithm permeability and sonic velocity.
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Scaffolds for bone tissue engineering should be designed to optimize cell migration, enhance new bone formation and give mechanical support. In the present study, we used polycaprolactone-tricalciumphosphate (PCL/TCP) scaffolds with two different fibre lay down patterns which were coated with hydroxyapatite and gelatine as an approach for optimizing bone regeneration in a critical sized calvarial defect. After 12 weeks bone regeneration was quantified using microCT analysis, biomechanical testing and histological evaluation. Notably, the experimental groups containing coated scaffolds showed lower bone formation and lower biomechanical properties within the defect compared to the uncoated scaffolds. Surprisingly, the different lay down pattern of the fibres resulted in different bone formation and biomechanical properties; namely 0/60/120° scaffolds revealed lower bone formation and biomechanical properties compared to the 0/90° scaffolds in all the experimental groups. The different architecture of the scaffold fibres may have an effect on nutrition supply as well as the attachment of the newly formed matrix to the scaffold. Therefore, future bone regeneration strategies utilising scaffolds should consider scaffold architecture as an important factor during the scaffold optimisation stages in order to move closer to a clinical application.
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Objectives: Some doctors perform the dual roles of prescribing and dispensing pharmaceuticals. The dispensing doctors (DDs) role may give rise to prescribing behaviours that vary from those of non-DDs. The aim of this review was to systematically and comparatively appraise the research evidence related to the practices of DDs. Methods: A systematic search of bibliographic databases and reference lists from selected papers were the sources of the data. Inclusion criteria were papers published in English, between 1970 and 2008 that provided quantitative data comparing the practices of DDs and non-DDs. At least two of the authors abstracted data from all eligible papers using a purpose-made data extraction form. Results: Twenty-one papers were included in this review. Evidence indicated that DDs prescribed more pharmaceutical items and less often generically than non-DDs. There was limited evidence to suggest that DDs prescribed less judiciously and were associated with poor dispensing standards. Patient convenience and access to pharmaceuticals were main reasons for doctors to dispense. Conclusion: DDs can fill an important gap in the provision of pharmaceuticals for their patients especially where health workforce shortages exist. There was evidence the dispensing role influenced prescribing. Patient convenience should be balanced against scarce medical resources, being utilised for dispensing.
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Objective: To evaluate the prescribing practices of Australian dispensing doctors (DDs) and to explore their interpretations of the findings. Design, participants and setting: Sequential explanatory mixed methods. The quantitative phase comprised analysis of Pharmaceutical Benefits Scheme (PBS) claims data of DDs and non-DDs, 1 July 2005 30 June 2007. The qualitative phase involved semi-structured interviews with DDs in rural and remote general practice across Australian states, August 2009 February 2010. Main outcome measures: The number of PBS prescriptions per 1000 patients and use of Regulation 24 of the National Health (Pharmaceutical Benefits) Regulations 1960 (r. 24); DDs' interpretation of the findings. Results: 72 DDs' and 1080 non-DDs' PBS claims data were analysed quantitatively. DDs issued fewer prescriptions per 1000 patients (9452 v 15057; P = 0.003), even with a similar proportion of concessional patients and patients aged >65 years in their populations. DDs issued significantly more r. 24 prescriptions per 1000 prescriptions than non-DDs (314 v 67; P=0.008). Interviews with 22 DDs explained that the fewer prescriptions were due to perceived expectation from their peers regarding prescribing norms and the need to generate less administrative paperwork in small practices. Conclusions: Contrary to overseas findings, we found no evidence that Australian DDs overprescribed because of their additional dispensing role. MJA 2011; 195: 172-175
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The polyphagous moth Helicoverpa armigera (Hübner) is one of the world's most important agricultural pests. A number of existing approaches and future designs for management of H. armigera rely on the assumption that moths do not exhibit either genetically and/or non-genetically based variation for host plant utilization. We review recent empirical evidence demonstrating that both these forms of variation influence host plant use in this moth. The significance of this variation in H. armigera in relation to current and future pest management strategies is examined. We provide recommendations on future research needs and directions for sustainable management of H. armigera, under a framework that includes consideration of intra-specific variation for host use relevant in this and other similar pest species.
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Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the phosphate mineral fairfieldite. The Raman phosphate (PO4)3- stretching region shows strong differences between the fairfieldite phosphate minerals which is attributed to the cation substitution for calcium in the structure. In the infrared spectra complexity exists with multiple (PO4)2- antisymmetric stretching vibrations observed, indicating a reduction of the tetrahedral symmetry. This loss of degeneracy is also reflected in the bending modes. Strong Raman bands around 600 cm-1 are assigned to v4 phosphate bending modes. Multiple bands in the 400–450 cm-1 region assigned to m2 phosphate bending modes provide further evidence of symmetry reduction of the phosphate anion. Three broadbands for fairfieldite are found at 3040, 3139 and 3271 cm-1 and are assigned to OH stretching bands. By using a Libowitzky empirical equation hydrogen bond distances of 2.658 and 2.730 A are estimated. Vibrational spectroscopy enables aspects of the molecular structure of the fairfieldite to be ascertained.
Resumo:
In an attempt to deal with the potential problems presented by existing information systems, a shift towards the implementation of ERP packages has been witnessed. The common view, particularly the one espoused by vendors, is that ERP packages are most successfully implemented when the standard model is adopted. Yet, despite this, customisation activity still occurs reportedly due to misalignment between the functionality of the package and the requirements of those in the implementing organisation. However, it is recognised that systems development and organisational decision-making are activities influenced by the perspectives of the various groups and individuals involved in the process. Thus, as customisation can be seen as part of systems development, and has to be decided upon, it should be thought about in the same way. In this study, two ERP projects are used to examine different reasons why customisation might take place. These reasons are then built upon through reference to the ERP and more general packaged software literature. The study suggests that whilst a common reason for customising ERP packages might be concerned with functionality misfits, it is important to look further into why these may occur, as there are clearly other reasons for customisation stemming from the multiplicity of social groups involved in the process.
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Tilting-pad hydrodynamic thrust bearings are used in hydroelectric power stations around the world, reliably supporting turbines weighing hundreds of tonnes, over decades of service. Newer designs incorporate hydrostatic recesses machined into the sector-shaped pads to enhance oil film thickness at low rotational speeds. External pressurisation practically eliminates wear and enhances service life and reliability. It follows that older generating plants, lacking such assistance, stand to benefit from being retrofitted with hydrostatic lubrication systems. The design process is not trivial however. The need to increase the groove size to permit spontaneous lifting of the turbine under hydrostatic pressure, conflicts with the need to preserve performance of the original plane pad design. A haphazardly designed recess can induce a significant rise in bearing temperature concomitant with reduced mechanical efficiency and risk of thermal damage. In this work, a numerical study of a sector-shaped pad is undertaken to demonstrate how recess size and shape can affect the performance of a typical bearing.