917 resultados para Mixture Of Experts
Resumo:
Concerns have increased regarding the detection of endocrine-disrupting compounds in the effluents of sewage treatment plants (STPs). These compounds are able to disrupt normal function of the endocrine system of living organisms even at trace concentrations. Natural and synthetic steroid estrogens (SEs) are believed to be responsible for the majority of the endocrine-disrupting effects. Municipal sewage, the main source of SEs in the environment, is a complex mixture of a wide range of pollutants at concentrations much higher than those of SEs. Low concentrations of SEs in the presence of copollutants thus make their removal problematic. The main objectives of the present work were to study the potential of photocatalytic oxidation (PCO) to effectively treat SE-containing aqueous solutions and to identify the optimum conditions for such treatment. The results showed that SEs can be effectively degraded photocatalytically. Due to the adsorption properties of SEs on the TiO2 photocatalyst surface alkaline medium was found to be beneficial for SE oxidation despite the presence of co-pollutants in concentrations characteristic for the sanitary fraction of municipal sewage. The potential of PCO to selectively oxidise SEs was examined in the presence of copollutants of the sanitary fraction of sewage - urea, saccharose and human urine. The impact of ethanol, often used as a solvent in the preparation of SE stock solutions, was also studied and the results indicated the need to use organic solvent-free solutions for the study of SE behaviour. Photocatalytic oxidation of SEs appeared to be indifferent towards the presence of urea in concentrations commonly found in domestic sewage. The effect of other co-pollutants under consideration was far weaker than could be expected from their concentrations, which are from one hundred to a few thousands times higher than those of the SEs. Although higher concentrations can dramatically slow down the PCO of SEs, realistic concentrations of co-pollutants characteristic for the sanitary fraction of domestic sewage allowed selective removal of SEs. This indicates the potential of PCO to be a selective oxidation method for SE removal from the separate sanitary fraction of municipal sewage.
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BACKGROUND: Selective publication of studies, which is commonly called publication bias, is widely recognized. Over the years a new nomenclature for other types of bias related to non-publication or distortion related to the dissemination of research findings has been developed. However, several of these different biases are often still summarized by the term 'publication bias'. METHODS/DESIGN: As part of the OPEN Project (To Overcome failure to Publish nEgative fiNdings) we will conduct a systematic review with the following objectives:- To systematically review highly cited articles that focus on non-publication of studies and to present the various definitions of biases related to the dissemination of research findings contained in the articles identified.- To develop and discuss a new framework on nomenclature of various aspects of distortion in the dissemination process that leads to public availability of research findings in an international group of experts in the context of the OPEN Project.We will systematically search Web of Knowledge for highly cited articles that provide a definition of biases related to the dissemination of research findings. A specifically designed data extraction form will be developed and pilot-tested. Working in teams of two, we will independently extract relevant information from each eligible article.For the development of a new framework we will construct an initial table listing different levels and different hazards en route to making research findings public. An international group of experts will iteratively review the table and reflect on its content until no new insights emerge and consensus has been reached. DISCUSSION: Results are expected to be publicly available in mid-2013. This systematic review together with the results of other systematic reviews of the OPEN project will serve as a basis for the development of future policies and guidelines regarding the assessment and prevention of publication bias.
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BACKGROUND: Elucidating disease and developmental dysfunction requires understanding variation in phenotype. Single-species model organism anatomy ontologies (ssAOs) have been established to represent this variation. Multi-species anatomy ontologies (msAOs; vertebrate skeletal, vertebrate homologous, teleost, amphibian AOs) have been developed to represent 'natural' phenotypic variation across species. Our aim has been to integrate ssAOs and msAOs for various purposes, including establishing links between phenotypic variation and candidate genes. RESULTS: Previously, msAOs contained a mixture of unique and overlapping content. This hampered integration and coordination due to the need to maintain cross-references or inter-ontology equivalence axioms to the ssAOs, or to perform large-scale obsolescence and modular import. Here we present the unification of anatomy ontologies into Uberon, a single ontology resource that enables interoperability among disparate data and research groups. As a consequence, independent development of TAO, VSAO, AAO, and vHOG has been discontinued. CONCLUSIONS: The newly broadened Uberon ontology is a unified cross-taxon resource for metazoans (animals) that has been substantially expanded to include a broad diversity of vertebrate anatomical structures, permitting reasoning across anatomical variation in extinct and extant taxa. Uberon is a core resource that supports single- and cross-species queries for candidate genes using annotations for phenotypes from the systematics, biodiversity, medical, and model organism communities, while also providing entities for logical definitions in the Cell and Gene Ontologies. THE ONTOLOGY RELEASE FILES ASSOCIATED WITH THE ONTOLOGY MERGE DESCRIBED IN THIS MANUSCRIPT ARE AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases/2013-02-21/ CURRENT ONTOLOGY RELEASE FILES ARE AVAILABLE ALWAYS AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases/
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The term "spindle cell liposarcoma" has been applied to liposarcomas (LPSs) composed predominantly or exclusively of spindled cells. These tumors have been considered variants of well-differentiated LPS (WDL), myxoid LPS, and spindle cell lipoma, suggesting that this is a heterogenous group of lesions. Using strict morphologic criteria and molecular and immunohistochemical analyses, we have identified a homogenous group of spindle cell lipomatous tumors, histologically and genetically distinct from other forms of LPS, which we have called "fibrosarcoma-like lipomatous neoplasm." Cases classified as "spindle cell LPS" or "low-grade LPS with spindle cell features" were reviewed. Final selection criteria included: (1) an exclusive low-grade spindle cell component resembling fibrosarcoma; (2) a mixture of bland fibroblastic cells resembling the preadipocyte and early-adipocyte stage of embryonic fat; and (3) molecular-genetic analysis that excluded other forms of lipomatous tumors. Of the initial 25 cases identified, comparative genomic hybridization (CGH) was uninformative in 2 cases; 5 were reclassified as WDL on the basis of molecular data (MDM2 amplification) and 6 as spindle cell lipoma (CGH profiles with a few gains and losses including a constant loss of chromosome 13 and frequent losses of chromosomes 16 and 6). The 12 remaining cases showed flat CGH profiles; of these cases, 11 were negative for DDIT3 gene rearrangements, and 1 result was uninterpretable. Patients ranged in age from 15 to 82 years (mean 50 y); male patients were affected slightly more often (7:5). Tumors arose in the deep (6) and superficial (3) soft tissue of the groin (4), buttock (3), thigh (2), flank (1), shoulder (1), and paratesticular tissue (1) and ranged in size from 2 to 20 cm (mean 7.5 cm). Clinical follow-up in 11 patients (9 mo to 20 y; mean 68 mo) showed no recurrences or metastases. As defined above, "fibrosarcoma-like lipomatous neoplasm" is a unique lipomatous tumor that should be distinguished from WDL/(low-grade) dedifferentiated LPS and myxoid LPS on combined histologic/molecular features because of its better prognosis.
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High reflectivity to laser light, alloying element evaporation during high power laser welding makes aluminium alloys highly susceptibility to weld defects such as porosity, cracking and undercutting. The dynamic behaviour of the keyhole, due to fluctuating plasma above the keyhole and the vaporization ofthe alloying elements with in the keyhole, is the key problem to be solved for the improvement of the weld quality and stabilization of the keyhole dynamics isperhaps the single most important development that can broaden the application of laser welding of aluminium alloys. In laser welding, the shielding gas is commonly used to stabilize the welding process, to improve the welded joint features and to protect the welded seam from oxidation. The chemicalcomposition of the shielding gas is a key factor in achieving the final qualityof the welded joints. Wide range of shielding gases varying from the pure gasesto complex mixtures based on helium, argon, nitrogen and carbon dioxide are commercially available. These gas mixtures should be considered in terms of their suitability during laser welding of aluminium alloys to produce quality welds. The main objective of the present work is to study the effect of the shielding gascomposition during laser welding of aluminium alloys. Aluminium alloy A15754 was welded using 3kW Nd-YAG laser (continuous wave mode). The alloy samples were butt welded with different shielding gases (pure and mixture of gases) so that high quality welds with high joint efficiencies could be produced. It was observed that the chemical composition of the gases influenced the final weld quality and properties. In general, the mixture gases, in correct proportions, enabled better utilisation of the properties of the mixing gases, stabilized the welding process and produced better weld quality compared to the pure shielding gases.
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The nature of client-server architecture implies that some modules are delivered to customers. These publicly distributed commercial software components are under risk, because users (and simultaneously potential malefactors) have physical access to some components of the distributed system. The problem becomes even worse if interpreted programming languages are used for creation of client side modules. The language Java, which was designed to be compiled into platform independent byte-code is not an exception and runs the additional risk. Along with advantages like verifying the code before execution (to ensure that program does not produce some illegal operations)Java has some disadvantages. On a stage of byte-code a java program still contains comments, line numbers and some other instructions, which can be used for reverse-engineering. This Master's thesis focuses on protection of Java code based client-server applications. I present a mixture of methods to protect software from tortious acts. Then I shall realize all the theoretical assumptions in a practice and examine their efficiency in examples of Java code. One of the criteria's to evaluate the system is that my product is used for specialized area of interactive television.
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PAH (N-(4-aminobenzoyl)glycin) clearance measurements have been used for 50 years in clinical research for the determination of renal plasma flow. The quantitation of PAH in plasma or urine is generally performed by colorimetric method after diazotation reaction but the measurements must be corrected for the unspecific residual response observed in blank plasma. We have developed a HPLC method to specifically determine PAH and its metabolite NAc-PAH using a gradient elution ion-pair reversed-phase chromatography with UV detection at 273 and 265 nm, respectively. The separations were performed at room temperature on a ChromCart (125 mmx4 mm I.D.) Nucleosil 100-5 microm C18AB cartridge column, using a gradient elution of MeOH-buffer pH 3.9 1:99-->15:85 over 15 min. The pH 3.9 buffered aqueous solution consisted in a mixture of 375 ml sodium citrate-citric acid solution (21.01 g citric acid and 8.0 g NaOH per liter), added up with 2.7 ml H3PO4 85%, 1.0 g of sodium heptanesulfonate and completed ad 1000 ml with ultrapure water. The N-acetyltransferase activity does not seem to notably affect PAH clearances, although NAc-PAH represents 10.2+/-2.7% of PAH excreted unchanged in 12 healthy subjects. The performance of the HPLC and the colorimetric method have been compared using urine and plasma samples collected from healthy volunteers. Good correlations (r=0.94 and 0.97, for plasma and urine, respectively) are found between the results obtained with both techniques. However, the colorimetric method gives higher concentrations of PAH in urine and lower concentrations in plasma than those determined by HPLC. Hence, both renal (ClR) and systemic (Cls) clearances are systematically higher (35.1 and 17.8%, respectively) with the colorimetric method. The fraction of PAH excreted by the kidney ClR/ClS calculated from HPLC data (n=143) is, as expected, always <1 (mean=0.73+/-0.11), whereas the colorimetric method gives a mean extraction ratio of 0.87+/-0.13 implying some unphysiological values (>1). In conclusion, HPLC not only enables the simultaneous quantitation of PAH and NAc-PAH, but may also provide more accurate and precise PAH clearance measurements.
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Tools to predict fracture risk are useful for selecting patients for pharmacological therapy in order to reduce fracture risk and redirect limited healthcare resources to those who are most likely to benefit. FRAX® is a World Health Organization fracture risk assessment algorithm for estimating the 10-year probability of hip fracture and major osteoporotic fracture. Effective application of FRAX® in clinical practice requires a thorough understanding of its limitations as well as its utility. For some patients, FRAX® may underestimate or overestimate fracture risk. In order to address some of the common issues encountered with the use of FRAX® for individual patients, the International Society for Clinical Densitometry (ISCD) and International Osteoporosis Foundation (IOF) assigned task forces to review the medical evidence and make recommendations for optimal use of FRAX® in clinical practice. Among the issues addressed were the use of bone mineral density (BMD) measurements at skeletal sites other than the femoral neck, the use of technologies other than dual-energy X-ray absorptiometry, the use of FRAX® without BMD input, the use of FRAX® to monitor treatment, and the addition of the rate of bone loss as a clinical risk factor for FRAX®. The evidence and recommendations were presented to a panel of experts at the Joint ISCD-IOF FRAX® Position Development Conference, resulting in the development of Joint ISCD-IOF Official Positions addressing FRAX®-related issues.
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Personal results are presented to illustrate the development of immunoscintigraphy for the detection of cancer over the last 12 years, from the early experimental results in nude mice grafted with human colon carcinoma to the most modern form of immunoscintigraphy applied to patients, using I123 labeled Fab fragments from monoclonal anti-CEA antibodies detected by single photon emission computerized tomography (SPECT). The first generation of immunoscintigraphy used I131 labeled, immunoadsorbent purified, polyclonal anti-CEA antibodies and planar scintigraphy, as the detection system. The second generation used I131 labeled monoclonal anti-CEA antibodies and SPECT, while the third generation employed I123 labeled fragments of monoclonal antibodies and SPECT. The improvement in the precision of tumor images with the most recent forms of immunoscintigraphy is obvious. However, we think the usefulness of immunoscintigraphy for routine cancer management has not yet been entirely demonstrated. Further prospective trials are still necessary to determine the precise clinical role of immunoscintigraphy. A case report is presented on a patient with two liver metastases from a sigmoid carcinoma, who received through the hepatic artery a therapeutic dose (100 mCi) of I131 coupled to 40 mg of a mixture of two high affinity anti-CEA monoclonal antibodies. Excellent localisation in the metastases of the I131 labeled antibodies was demonstrated by SPECT and the treatment was well tolerated. The irradiation dose to the tumor, however, was too low at 4300 rads (with 1075 rads to the normal liver and 88 rads to the bone marrow), and no evidence of tumor regression was obtained. Different approaches for increasing the irradiation dose delivered to the tumor by the antibodies are considered.
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The dynamical properties ofshaken granular materials are important in many industrial applications where the shaking is used to mix, segregate and transport them. In this work asystematic, large scale simulation study has been performed to investigate the rheology of dense granular media, in the presence of gas, in a three dimensional vertical cylinder filled with glass balls. The base wall of the cylinder is subjected to sinusoidal oscillation in the vertical direction. The viscoelastic behavior of glass balls during a collision, have been studied experimentally using a modified Newton's Cradle device. By analyzing the results of the measurements, using numerical model based on finite element method, the viscous damping coefficient was determinedfor the glass balls. To obtain detailed information about the interparticle interactions in a shaker, a simplified model for collision between particles of a granular material was proposed. In order to simulate the flow of surrounding gas, a formulation of the equations for fluid flow in a porous medium including particle forces was proposed. These equations are solved with Large Eddy Simulation (LES) technique using a subgrid-model originally proposed for compressible turbulent flows. For a pentagonal prism-shaped container under vertical vibrations, the results show that oscillon type structures were formed. Oscillons are highly localized particle-like excitations of the granular layer. This self-sustaining state was named by analogy with its closest large-scale analogy, the soliton, which was first documented by J.S. Russell in 1834. The results which has been reportedbyBordbar and Zamankhan(2005b)also show that slightly revised fluctuation-dissipation theorem might apply to shaken sand, which appears to be asystem far from equilibrium and could exhibit strong spatial and temporal variations in quantities such as density and local particle velocity. In this light, hydrodynamic type continuum equations were presented for describing the deformation and flow of dense gas-particle mixtures. The constitutive equation used for the stress tensor provides an effective viscosity with a liquid-like character at low shear rates and a gaseous-like behavior at high shear rates. The numerical solutions were obtained for the aforementioned hydrodynamic equations for predicting the flow dynamics ofdense mixture of gas and particles in vertical cylindrical containers. For a heptagonal prism shaped container under vertical vibrations, the model results were found to predict bubbling behavior analogous to those observed experimentally. This bubbling behavior may be explained by the unusual gas pressure distribution found in the bed. In addition, oscillon type structures were found to be formed using a vertically vibrated, pentagonal prism shaped container in agreement with computer simulation results. These observations suggest that the pressure distribution plays a key rolein deformation and flow of dense mixtures of gas and particles under vertical vibrations. The present models provide greater insight toward the explanation of poorly understood hydrodynamic phenomena in the field of granular flows and dense gas-particle mixtures. The models can be generalized to investigate the granular material-container wall interactions which would be an issue of high interests in the industrial applications. By following this approach ideal processing conditions and powder transport can be created in industrial systems.
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The aim of this study is to provide an instrument for measuring service quality in sports enterprises from the point of view of the customers. For this purpose we intend to elaborate an enquiry starting out from a more general scale called SERVIQUAL. We have limited our research project to sports enterprises where the customer participates actively, i.e., we have excluded sports clubs and other organizations which offer sport as entertainment. Our choice is mainly due to the fact that few studies have been carried out in this area and that sports has been earning an increasing amount of adepts during the last decades in Spain. The DELPHI method has been applied with the collaboration of a panel of experts in order to evaluate the viability and adequacy of the modified SERVQUAL scale.
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Background: During the last part of the 1990s the chance of surviving breast cancer increased. Changes in survival functions reflect a mixture of effects. Both, the introduction of adjuvant treatments and early screening with mammography played a role in the decline in mortality. Evaluating the contribution of these interventions using mathematical models requires survival functions before and after their introduction. Furthermore, required survival functions may be different by age groups and are related to disease stage at diagnosis. Sometimes detailed information is not available, as was the case for the region of Catalonia (Spain). Then one may derive the functions using information from other geographical areas. This work presents the methodology used to estimate age- and stage-specific Catalan breast cancer survival functions from scarce Catalan survival data by adapting the age- and stage-specific US functions. Methods: Cubic splines were used to smooth data and obtain continuous hazard rate functions. After, we fitted a Poisson model to derive hazard ratios. The model included time as a covariate. Then the hazard ratios were applied to US survival functions detailed by age and stage to obtain Catalan estimations. Results: We started estimating the hazard ratios for Catalonia versus the USA before and after the introduction of screening. The hazard ratios were then multiplied by the age- and stage-specific breast cancer hazard rates from the USA to obtain the Catalan hazard rates. We also compared breast cancer survival in Catalonia and the USA in two time periods, before cancer control interventions (USA 1975–79, Catalonia 1980–89) and after (USA and Catalonia 1990–2001). Survival in Catalonia in the 1980–89 period was worse than in the USA during 1975–79, but the differences disappeared in 1990–2001. Conclusion: Our results suggest that access to better treatments and quality of care contributed to large improvements in survival in Catalonia. On the other hand, we obtained detailed breast cancer survival functions that will be used for modeling the effect of screening and adjuvant treatments in Catalonia.
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The effects of 0, 30 and 60 mM NaCl and substrates (red peat, sand or 3:1:1 [w/w] mixture of peat, sand, or soil) on vegetative growth of lulo, an Andean fruit species, during 12 weeks were studied. The experiment was carried out by using 2000 cm³ of polypropylene plastic pots under greenhouse conditions. Plant height, number of leaves and nodes, leaf area, total plant dry matter (DM), and shoot/root ratio were evaluated. With the increase of salt concentration, the plant height, the number of leaves and nodes, the leaf areas and plant dry mass DM decreased, whereas shoot/root ratio increased. Sand grown lulo plants were most affected by salinity and presented total mortality at 60 mM NaCl. On the other hand, plants held either in peat or in substrate mixture developed larger height, greater leaf and node numbers, higher leaf area and dry matter content. Shoot/root ratio in control (soil) and sand-grown plants (30 mM NaCl) was lower.
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The analysis of the shape of excitation-emission matrices (EEMs) is a relevant tool for exploring the origin, transport and fate of dissolved organic matter (DOM) in aquatic ecosystems. Within this context, the decomposition of EEMs is acquiring a notable relevance. A simple mathematical algorithm that automatically deconvolves individual EEMs is described, creating new possibilities for the comparison of DOM fluorescence properties and EEMs that are very different from each other. A mixture model approach is adopted to decompose complex surfaces into sub-peaks. The laplacian operator and the Nelder-Mead optimisation algorithm are implemented to individuate and automatically locate potential peaks in the EEM landscape. The EEMs of a simple artificial mixture of fluorophores and DOM samples collected in a Mediterranean river are used to describe the model application and to illustrate a strategy that optimises the search for the optimal output.
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In this study, 13 ceramic samples were subjected to dissolution using three different procedures: (a) acid attack in open PTFE vessels with a mixture of HF-HClO4, (b) fusion of the sample with lithium metaborate and (c) microwave digestion in PTFE bombs. The samples used in the study had been previously analyzed by neutron activation analysis (NAA), X-ray fluorescence (XRF) and X-ray diffraction (XRD) and they cover a wide range of ceramics fired in different atmospheres and temperatures as well as different mineralogical and chemical compositions. The effectiveness of each procedure is evaluated in terms of its ability to dissolve the various mineralogical phases of the samples, of the number of elements that can be determined and of the time needed for the whole scheme of analysis to be completed.