983 resultados para comparison of diagnosis techniques


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A quantitative comparison of up to 40 Gb/s low-cost orthogonal frequency-division multiplexing access (OFDMA)-passive optical networks (PON) implementations for both upstream (US) and downstream (DS) directions is evaluated based on different modulation and detection techniques. © 2012 IEEE.

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A fenntarthatóság értékelése definíciószerűen többdimenziós probléma. A megfelelő alternatíva, forgatókönyv, eljárás stb. kiválasztásakor ugyanis a döntéshozóknak egyszerre kell figyelembe venniük környezetvédelmi, gazdasági és társadalmi szempontokat. Az ilyen döntéseket alátámaszthatják a több szempontú döntéshozatali modellek. A tanulmány a több szempontú döntési eljárások közül a legfontosabb hétnek az alkalmazhatóságát vizsgálja részvételi körülmények között. Az utóbbi évek e témában publikált esettanulmányainak áttekintésével megállapítható, hogy egyik módszer sem uralja a többit, azok különböző feltételek mellett eltérő sikerrel használhatók. Ennek ellenére a különböző módszerek kombinációjával végrehajthatunk olyan eljárásokat, amelyekkel az egyes módszerek előnyeit még jobban kiaknázhatjuk. ________ Measuring and comparing the sustainability of certain actions, scenarios, technologies, etc. is by definition a multidimensional problem. Decision-makers must consider environmental, economic and social aspects when choosing an alternative course of action. Such decisions can be aided by multi-criteria decision analysis (MCDA). This paper investigates seven different MCDA methodologies: MAU, the Analytic Hierarchic Process (AHP), the ELECTRE, PROMETHEE, REGIME, and NAIADE methods, and "Ideal and reference point" approaches). It is based on a series of reports in which over 30 real-world case studies focusing on participatory MCDA were reviewed. It is stressed, however, that there is no "best" choice in the list of MCDA techniques. Some methods fit certain decision problems better than others. Nonetheless, some complementary benefits of the different techniques can be exploited by combining these methodologies.

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The elemental analysis of soil is useful in forensic and environmental sciences. Methods were developed and optimized for two laser-based multi-element analysis techniques: laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS). This work represents the first use of a 266 nm laser for forensic soil analysis by LIBS. Sample preparation methods were developed and optimized for a variety of sample types, including pellets for large bulk soil specimens (470 mg) and sediment-laden filters (47 mg), and tape-mounting for small transfer evidence specimens (10 mg). Analytical performance for sediment filter pellets and tape-mounted soils was similar to that achieved with bulk pellets. An inter-laboratory comparison exercise was designed to evaluate the performance of the LA-ICP-MS and LIBS methods, as well as for micro X-ray fluorescence (μXRF), across multiple laboratories. Limits of detection (LODs) were 0.01-23 ppm for LA-ICP-MS, 0.25-574 ppm for LIBS, 16-4400 ppm for μXRF, and well below the levels normally seen in soils. Good intra-laboratory precision (≤ 6 % relative standard deviation (RSD) for LA-ICP-MS; ≤ 8 % for μXRF; ≤ 17 % for LIBS) and inter-laboratory precision (≤ 19 % for LA-ICP-MS; ≤ 25 % for μXRF) were achieved for most elements, which is encouraging for a first inter-laboratory exercise. While LIBS generally has higher LODs and RSDs than LA-ICP-MS, both were capable of generating good quality multi-element data sufficient for discrimination purposes. Multivariate methods using principal components analysis (PCA) and linear discriminant analysis (LDA) were developed for discriminations of soils from different sources. Specimens from different sites that were indistinguishable by color alone were discriminated by elemental analysis. Correct classification rates of 94.5 % or better were achieved in a simulated forensic discrimination of three similar sites for both LIBS and LA-ICP-MS. Results for tape-mounted specimens were nearly identical to those achieved with pellets. Methods were tested on soils from USA, Canada and Tanzania. Within-site heterogeneity was site-specific. Elemental differences were greatest for specimens separated by large distances, even within the same lithology. Elemental profiles can be used to discriminate soils from different locations and narrow down locations even when mineralogy is similar.

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Lower jaws (containing the teeth), eyes, and skin samples were collected from harp seals (Pagophilus groenlandicus) in the southeastern Barents Sea for the purpose of comparing age estimates obtained by 3 different methods, the traditional technique of counting growth layer groups (GLGs) in teeth and 2 novel approaches, aspartic acid racemization (AAR) in eye lens nuclei and telomere sequence analyses as a proxy for telomere length. A significant correlation between age estimates obtained using GLGs and AAR was found, whereas no correlation was found between GLGs and telomere length. An AAR rate (k Asp) of 0.00130/year ± 0.00005 SE and a D-enantiomer to L-enantiomer ratio at birth (D/L 0 value) of 0.01933 ± 0.00048 SE were estimated by regression of D/L ratios against GLG ages from 25 animals (12 selected teeth that had high readability and 13 known-aged animals). AAR could prove to be useful, particularly for ageing older animals in species such as harp seals where difficulties in counting GLGs tend to increase with age. Age estimation by telomere length did not show any correlation with GLG ages and is not recommended for harp seals.

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The fast developing international trade of products based on traditional knowledge and their value chains has become an important aspect of the ethnopharmacological debate. The structure and diversity of value chains and their impact on the phytochemical composition of herbal medicinal products has been overlooked in the debate about quality problems in transnational trade. Different government policies and regulations governing trade in herbal medicinal products impact on such value chains. Medicinal Rhodiola species, including Rhodiola rosea L. and Rhodiola crenulata (Hook.f. & Thomson) H.Ohba, have been used widely in Europe and Asia as traditional herbal medicines with numerous claims for their therapeutic effects. Faced with resource depletion and environment destruction, R. rosea and R. crenulata are becoming endangered, making them more economically valuable to collectors and middlemen, and also increasing the risk of adulteration and low quality. We compare the phytochemical differences among Rhodiola raw materials available on the market to provide a practical method for Rhodiola authentication and the detection of potential adulterant compounds. Samples were collected from Europe and Asia and nuclear magnetic resonance spectroscopy coupled with multivariate analysis software and high performance thin layer chromatography techniques were used to analyse the samples. A method was developed to quantify the amount of adulterant species contained within mixtures. We compared the phytochemical composition of collected Rhodiola samples to authenticated samples. Rosavin and rosarin were mainly present in R. rosea whereas crenulatin was only present in R. crenulata. 30% of the Rhodiola samples purchased from the Chinese market were adulterated by other Rhodiola spp. Moreover, 7 % of the raw-material samples were not labelled satifactorily. The utilisation of both 1H-NMR and HPTLC methods provided an integrated analysis of the phytochemical differences and novel identification method for R. rosea and R. crenulata. Using 1H-NMR spectroscopy it was possible to quantify the presence of R. crenulata in admixtures with R. rosea. This quantitative technique could be used in the future to assess a variety of herbal drugs and products. This project also highlights the need to further study the links between producers and consumers in national and trans-national trade.

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In the context of products from certain regions or countries being banned because of an identified or non-identified hazard, proof of geographical origin is essential with regard to feed and food safety issues. Usually, the product labeling of an affected feed lot shows origin, and the paper documentation shows traceability. Incorrect product labeling is common in embargo situations, however, and alternative analytical strategies for controlling feed authenticity are therefore needed. In this study, distillers' dried grains and solubles (DDGS) were chosen as the product on which to base a comparison of analytical strategies aimed at identifying the most appropriate one. Various analytical techniques were investigated for their ability to authenticate DDGS, including spectroscopic and spectrometric techniques combined with multivariate data analysis, as well as proven techniques for authenticating food, such as DNA analysis and stable isotope ratio analysis. An external validation procedure (called the system challenge) was used to analyze sample sets blind and to compare analytical techniques. All the techniques were adapted so as to be applicable to the DDGS matrix. They produced positive results in determining the botanical origin of DDGS (corn vs. wheat), and several of them were able to determine the geographical origin of the DDGS in the sample set. The maintenance and extension of the databanks generated in this study through the analysis of new authentic samples from a single location are essential in order to monitor developments and processing that could affect authentication.

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Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue neoplasm of intermediate biologic potential and uncertain differentiation, most often arising in the extremities of children and young adults. Although it has characteristic histologic features of a lymphoid cuff surrounding nodules of ovoid cells with blood-filled cystic cavities, diagnosis is often difficult due to its morphologic heterogeneity and lack of specific immunoprofile. Angiomatoid fibrous histiocytoma is associated with recurrent chromosomal translocations, leading to characteristic EWSR1-CREB1, EWSR1-ATF1, and, rarely, FUS-ATF1 gene fusions; fluorescence in situ hybridization (FISH), detecting EWSR1 or FUS rearrangements, and reverse transcription-polymerase chain reaction (RT-PCR) for EWSR1-CREB1 and EWSR1-ATF1 fusion transcripts have become routine ancillary tools. We present a large comparative series of FISH and RT-PCR for AFH. Seventeen neoplasms (from 16 patients) histologically diagnosed as AFH were assessed for EWSR1 rearrangements or EWSR1-CREB1 and EWSR1-ATF1 fusion transcripts. All 17 were positive for either FISH or RT-PCR or both. Of 16, 14 (87.5%) had detectable EWSR1-CREB1 or EWSR1-ATF1 fusion transcripts by RT-PCR, whereas 13 (76.5%) of 17 had positive EWSR1 rearrangement with FISH. All 13 of 13 non-AFH control neoplasms failed to show EWSR1-CREB1 or EWSR1-ATF1 fusion transcripts, whereas EWSR1 rearrangement was present in 2 of these 13 cases (which were histopathologically myoepithelial neoplasms). This study shows that EWSR1-CREB1 or EWSR1-ATF1 fusions predominate in AFH (supporting previous reports that FUS rearrangement is rare in AFH) and that RT-PCR has a comparable detection rate to FISH for AFH. Importantly, cases of AFH can be missed if RT-PCR is not performed in conjunction with FISH, and RT-PCR has the added advantage of specificity, which is crucial, as EWSR1 rearrangements are present in a variety of neoplasms in the histologic differential diagnosis of AFH, that differ in behavior and treatment.

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International audience

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The phosphodiesterase 4 (PDE4) family are cAMP specific phosphodiesterases that play an important role in the inflammatory response and is the major PDE type found in inflammatory cells. A significant number of PDE4 specific inhibitors have been developed and are currently being investigated for use as therapeutic agents. Apremilast, a small molecule inhibitor of PDE 4 is in development for chronic inflammatory disorders and has shown promise for the treatment of psoriasis, psoriatic arthritis as well as other inflammatory diseases. It has been found to be safe and well tolerated in humans and in March 2014 it was approved by the US food and drug administration for the treatment of adult patients with active psoriatic arthritis. The only other PDE4 inhibitor on the market is Roflumilast and it is used for treatment of respiratory disease. Roflumilast is approved in the EU for the treatment of COPD and was recently approved in the US for treatment to reduce the risk of COPD exacerbations. Roflumilast is also a selective PDE4 inhibitor, administered as an oral tablet once daily, and is thought to act by increasing cAMP within lung cells. As both (Apremilast and Roflumilast) compounds selectively inhibit PDE4 but are targeted at different diseases, there is a need for a clear understanding of their mechanism of action (MOA). Differences and similarity of MOA should be defined for the purposes of labelling, for communication to the scientific community, physicians, and patients, and for an extension of utility to other diseases and therapeutic areas. In order to obtain a complete comparative picture of the MOA of both inhibitors, additional molecular and cellular biology studies are required to more fully elucidate the signalling mediators downstream of PDE4 inhibition which result in alterations in pro- and anti-inflammatory gene expression. My studies were conducted to directly compare Apremilast with Roflumilast, in order to substantiate the differences observed in the molecular and cellular effects of these compounds, and to search for other possible differentiating effects. Therefore the main aim of this thesis was to utilise cutting-edge biochemical techniques to discover whether Apremilast and Roflumilast work with different modes of action. In the first part of my thesis I used novel genetically encoded FRET based cAMP sensors targeted to different intracellular compartments, in order to monitor cAMP levels within specific microdomains of cells as a consequence of challenge with Apremilast and Roflumilast, which revealed that Apremilast and Roflumilast do regulate different pools of cAMP in cells. In the second part of my thesis I focussed on assessing whether Apremilast and Roflumilast cause differential effects on the PKA phosphorylation state of proteins in cells. I used various biochemical techniques (Western blotting, Substrate kinase arrays and Reverse Phase Protein array and found that Apremilast and Roflumilast do lead to differential PKA substrate phosphorylation. For example I found that Apremilast increases the phosphorylation of Ribosomal Protein S6 at Ser240/244 and Fyn Y530 in the S6 Ribosomal pathway of Rheumatoid Arthritis Synovial fibroblast and HEK293 cells, whereas Roflumilast does not. This data suggests that Apremilast has distinct biological effects from that of Roflumilast and could represent a new therapeutic role for Apremilast in other diseases. In the final part of my thesis, Phage display technology was employed in order to identify any novel binding motifs that associate with PDE4 and to identify sequences that were differentially regulated by the inhibitors in an attempt to find binding motifs that may exist in previously characterised signalling proteins. Petide array technology was then used to confirm binding of specific peptide sequences or motifs. Results showed that Apremilast and Roflumilast can either enhance or decrease the binding of PDE4A4 to specific peptide sequences or motifs that are found in a variety of proteins in the human proteome, most interestingly Ubiquitin-related proteins. The data from this chapter is preliminary but may be used in the discovery of novel binding partners for PDE4 or to provide a new role for PDE inhibition in disease. Therefore the work in this thesis provides a unique snapshot of the complexity of the cAMP signalling system and is the first to directly compare action of the two approved PDE4 inhibitors in a detailed way.

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The objective of this study was to assess the impact of the filtration method (in situ vs. ex situ) on the dissolved/particulate partitioning of 12 elements in hydrothermal samples collected from the Lucky Strike vent field (Mid-Atlantic Ridge; MAR). To do so, dissolved ( <0.45 mu m) and particulate Mg, Li, Mn, U, V, As, Ba, Fe, Zn, Cd, Pb and Cu were measured using different techniques (HR-ICP-MS, ICP-AES and CCSA). Using in situ filtration as a baseline, we showed that ex situ filtration (on-board and on shore after freezing) resulted in an underestimation of the dissolved pool, which was counterbalanced by an overestimation of the particulate pool for almost all the elements studied. We also showed that on-board filtration was acceptable for the assessment of dissolved and particulate Mn, Mg, Li and U for which the measurement bias for the dissolved fraction did not exceed 3%. However, in situ filtration appeared necessary for the accurate assessment of the dissolved and particulate concentrations of V, As, Fe, Zn, Ba, Cd, Pb and Cu. In the case of Fe, on-board filtration underestimated the dissolved pool by up to 96%. Laboratory filtration (after freezing) resulted in a large bias in the dissolved and particulate concentrations, unambiguously discounting this filtration method for deep-sea chemical speciation studies. We discuss our results in light of the precipitation processes that can potentially affect the accuracy of ex situ filtration methods.

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The temporal passage of fruit through the supply chain and the selection of consumable fruit by shoppers depend primarily upon fruit firmness. Traditionally, fruit firmness measuring methods, like Effegi and conical probes, are relatively inefficient and destructive. Simple, accurate and non-damaging methods of measuring fruit firmness are ideally required to help assure eating quality to the consumer without fruit wastage. The firmness of 'Hass' avocado fruit at a range of ripening stages was measured with the various different firmness measuring techniques of the Sinclair iQ Firmness Tester (SIQFT), the Electronic Firmometer (EF), the Analogue Firmness Meter (AFM) and hand squeezing. Measurements were made by each method at different points on the same fruit. Destructive bruise assessment was performed 48 h later, thereby allowing sufficient time for fruit to express any bruising resulting from the act of firmness measurements. Non-linear relationships were determined between fruit firmness values measured with the different techniques. The adjusted R2 for the relationship between the SIQFT and the EF was 91.6%. For the SIQFT and the AFM, the adjusted R2 was 73.7%. It was 77.7% for the SIQFT and hand squeezing. A significantly (P<0.05) high incidence of bruising was associated with firmness assessment by the EF as compared with either the SIQFT or the AFM. Among the methods compared, the SIQFT was non-damaging compared with the EF and relatively efficient for measuring the firmness. This instrument merits consideration as a quality control tool of choice in 'Hass' avocado supply chains.

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Background: For the diagnosis of frailty exhaustion is a criteria currently measured by self-reported questionnaires, which are subjective and dependent on individual perception. The FR test has been developed as a bed side objective evaluation of muscle fatigue. The test was validated for the VM. However, the JD is frequently used to measure the grip strength. So the comparison of these devices is required to understand if FR is similar when measured with both devices. Methods: Fifty-four (29 female and 25 male; mean age: 39.98 ± 18.09) community-dwelling people were tested for muscle function. The Fatigue resistance (FR), which is the time during that grip strength drops to 50% of its maximum, was recorded with each device and simultaneous sEMG of the forearm muscles was obtained. The (co-)activation of agonist and antagonist muscles was calculated and compared with the differences between the performances with each device (controlling for gender and age). Results: FR was significantly better when measured with VM compared to JD. At all phases of the FR-test the antagonist muscle co-activation was significantly higher for VM compared to JD. In contrast, the agonist muscle activation level was significantly higher in JD compared to VM. When performing the FR-test with VM, both the agonist muscle activation and antagonist muscle co-activation decreased significantly (p<0.05). Whereas when using the JD, only a significant decrease in the antagonist muscle co-activation was observed. The difference in antagonist muscle activation between VM and JD was significantly related to the difference in FR between both devices. Conclusion: The results suggest that the FR-test when using the VM induces a more prominent muscle exhaustion than when using the JD, which makes the VM more suitable for measuring muscle fatigue resistance. However, these findings must be confirmed in a larger study population.

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[EN] Since Long's Interaction Hypothesis (Long, 1983) multiple studies have suggested the need of oral interaction for successful second language learning. Within this perspective, a great deal of research has been carried out to investigate the role of corrective feedback in the process of acquiring a second language, but there are still varied open debates about this issue. This comparative study seeks to contribute to the existing literature on corrective feedback in oral interaction by exploring teachers' corrective techniques and students' response to these corrections. Two learning contexts were observed and compared: a traditional English as a foreign language (EFL) classroom and a Content and Language Integrated Learning (CLIL) classroom .The main aim was to see whether our data conform to the Counterbalance Hypothesis proposed by Lyster and Mori (2006). Although results did not show significant differences between the two contexts, a qualitative analysis of the data shed some light on the differences between these two language teaching settings. The findings point to the need for further research on error correction in EFL and CLIL contexts in order to overcome the limitations of the present study.

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This study aimed to evaluate the accuracy of magnetic resonance imaging (MRI) in the detection of deep myometrial invasion and cervical extension by endometrial carcinoma. This prospective study included 101 patients with histologically documented endometrial carcinoma, between July 1998 and April 2004. The findings of preoperative pelvic MRI were compared with histological diagnosis. From 101 cases studied by pelvic MRI, 43 were classified as deep myometrial invasion (50% of myometrium), where the pathological evaluation confirmed as having deep myometrial invasion. Cervical extension in the MRI study was found in 19 cases. Pathologic study found cervical extension and/or invasion in 31 cases including all cases identified by MRI. The accuracy, sensitivity and specificity of MRI were 95%, 89%, 100%, detecting deep myometrial invasion and 88%, 61%, 100%, detecting cervical invasion, respectively. The high accuracy achieved makes MRI an adequate method for determine the depth of myometrial and cervical invasion in endometrial carcinoma.