930 resultados para The Matrix
Resumo:
BACKGROUND: Genetic factors play a role in chronic obstructive pulmonary disease (COPD) but are poorly understood. A number of candidate genes have been proposed on the basis of the pathogenesis of COPD. These include the matrix metalloproteinase (MMP) genes which play a role in tissue remodelling and fit in with the protease--antiprotease imbalance theory for the cause of COPD. Previous genetic studies of MMPs in COPD have had inadequate coverage of the genes, and have reported conflicting associations of both single nucleotide polymorphisms (SNPs) and SNP haplotypes, plausibly due to under-powered studies. METHODS: To address these issues we genotyped 26 SNPs, providing comprehensive coverage of reported SNP variation, in MMPs- 1, 9 and 12 from 977 COPD patients and 876 non-diseased smokers of European descent and evaluated their association with disease singly and in haplotype combinations. We used logistic regression to adjust for age, gender, centre and smoking history. RESULTS: Haplotypes of two SNPs in MMP-12 (rs652438 and rs2276109), showed an association with severe/very severe disease, corresponding to GOLD Stages III and IV. CONCLUSIONS: Those with the common A-A haplotype for these two SNPs were at greater risk of developing severe/very severe disease (p = 0.0039) while possession of the minor G variants at either SNP locus had a protective effect (adjusted odds ratio of 0.76; 95% CI 0.61 - 0.94). The A-A haplotype was also associated with significantly lower predicted FEV1 (42.62% versus 44.79%; p = 0.0129). This implicates haplotypes of MMP-12 as modifiers of disease severity.
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El principal objectiu d'aquest treball és implementar i exposar una descripció teòrica per a diferents esquemes de Physical Layer Network Coding. Utilitzant un esquema bàsic com a punt de partida, el projecte presenta la construcció i l'anàlisis de diferents esquemes de comunicació on la complexitat va augmentant a mesura que anem avançant en el projecte. El treball està estructurat en diferents parts: primer, es presenta una introducció a Physical Layer Network Coding i a Lattice Network Codes. A continuació, s'introdueixen les eines matemàtiques necessàries per entendre el CF System. Després, s'analitza i implementa el primer esquema bàsic. A partir del qual, implementem una versió vectorial del CF System i una versió codificada amb un Hamming q-ari. Finalment, s'estudien i implementen diferents estratègies per millorar la matriu de coeficients A.
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In experimental areas of the Education and Researches Ilha Solteira and Jaboticabal UNESP/Campus farms were selected and tagged 20 hermaphrodite plants and 20 feminine of cultivar Sunrise Solo, Improved Sunrise Solo cv.72/12 and Baixinho of Santa Amália.The seeds origined of the selected fruits were cropped to be analysed the self-pollination efficiency and frequency of the sex in the progenies. After that, samples of the young leaf of the matrix plants were colected for the extration of the DNA. It was built five library enriched of microsatellite sequencies, using probes (TCA)10, (TC)13, (GATA)4, (CAC)10 e (TGAG)8.It was possible the development of the primers only in the library that has utilized the probe (TCA)10. This probe allowed the design of 32 primer pairs. From these, 31 presented pattern of unique band in agarose Metaphor and in acrilamide. For primer S36 were observed 2 bands, but with no polymorphism to differentiation in the sexual form at papaya tree culture. However, these primers can be tested, in the futures, in the investigation of the others features in segregated populations of this specie and the related species, germoplasm analysis, cultivars identification, parent evolution and molecular markers for the assisted plant breeding programs.
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L'aquifère du Seeland représente une richesse en ressources hydriques qu'il est impératif de préserver contre tout risque de détérioration. Cet aquifère prolifique est constitué principalement de sédiments alluviaux post-glaciaires (graviers, sables et limons). Il est soumis aux contraintes environnementales des pratiques d'agriculture intensive, du réseau routier, des villes et de leurs activités industrielles. La connaissance optimale de ces ressources est donc primordiale pour leur protection. Dans cette optique, deux sites Kappelen et Grenchen représentatifs de l'aquifère du Seeland ont été étudiés. L'objectif de ce travail est de caractériser d'un point de vue hydrogéophysique l'aquifère au niveau de ces deux sites, c'est-à-dire, comprendre la dynamique des écoulements souterrains par l'application des méthodes électriques de surface associées aux diagraphies en intégrant des méthodes hydrogéologiques. Pour le site de Kappelen, les méthodes électriques de surface ont permis d'identifier les différents faciès géoélectriques en présence et de mettre en évidence leur disposition en une structure tabulaire et horizontale. Il s'agit d'un aquifère libre constitué d'une série de graviers allant jusqu'à 15 m de profondeur reposant sur de la moraine argileuse. Les diagraphies électriques, nucléaires et du fluide ont servis à la détermination des caractéristiques pétrophysiques et hydrauliques de l'aquifère qui contrôlent son comportement hydrodynamique. Les graviers aquifères de Kappelen présentent deux minéraux dominants: quartz et calcite. Les analyses minéralogiques indiquent que ces deux éléments constituent 65 à 75% de la matrice. La porosité totale obtenue par les diagraphies nucléaires varie de 20 à 30 %, et de 22 à 29 % par diagraphies électrique. Avec les faibles valeurs de Gamma Ray ces résultats indiquent que l'aquifère des graviers de Kappelen est dépourvu d'argile minéralogique. La perméabilité obtenue par diagraphies du fluide varie de 3.10-4 à 5.10-2 m/s, et par essais de pompage de 10-4 à 10-2 m/s. Les résultats des analyses granulométriques indiquent une hétérogénéité granulométrique au niveau des graviers aquifères. La fraction de sables, sables très fins, silts et limons constitue de 10 à 40 %. Ces éléments jouent un rôle important dans le comportement hydraulique de l'aquifère. La porosité efficace de 11 à 25% estimée à partir des résultats des analyses granulométriques suppose que les zones les plus perméables correspondent aux zones les plus graveleuses du site. Etablie sur le site de Kappelen, cette méthodologie a été utilisée sur le site de Grenchen. Les méthodes électriques de surface indiquent que l'aquifère captif de Grenchen est constitué des sables silteux comprenant des passages sableux, encadrés par des silts argileux imperméables. L'aquifère de Grenchen est disposé dans une structure relativement tabulaire et horizontale. Son épaisseur totale peut atteindre les 25 m vers le sud et le sud ouest ou les passages sableux sont les plus importants. La détermination des caractéristiques pétrophysiques et hydrauliques s'est faite à l'aide des diagraphies. Les intensités Gamma Ray varient de 30 à 100 cps, les plus fortes valeurs n'indiquent qu'une présence d'éléments argileux mais pas de bancs d'argile. Les porosités totales de 15 à 25% et les densités globales de 2.25 à 2.45 g/cm3 indiquent que la phase minérale (matrice) est composée essentiellement de quartz et de calcaire. Les densités de matrice varient entre 2.65 et 2.75 g/cm3. La perméabilité varie de 2 10-6 à 5 10-4 m/s. La surestimation des porosités totales à partir des diagraphies électriques de 25 à 42% est due à la présence d'argiles. -- The vast alluvial Seeland aquifer system in northwestern Switzerland is subjected to environmental challenges due to intensive agriculture, roads, cities and industrial activities. Optimal knowledge of the hydrological resources of this aquifer system is therefore important for their protection. Two representative sites, Kappelen and Grenchen, of the Seeland aquifer were investigated using surface-based geoelectric methods and geophysical borehole logging methods. By integrating of hydrogeological and hydrogeophysical methods, a reliable characterization of the aquifer system at these two sites can be performed in order to better understand the governing flow and transport process. At the Kappelen site, surface-based geoelectric methods allowed to identify various geoelectric facies and highlighted their tabular and horizontal structure. It is an unconfined aquifer made up of 15 m thick gravels with an important sandy fraction and bounded by a shaly glacial aquitard. Electrical and nuclear logging measurements allow for constraining the petrophysical and hydrological parameters of saturated gravels. Results indicate that in agreement with mineralogical analyses, matrix of the probed formations is dominated by quartz and calcite with densities of 2.65 and 2.71 g/cc, respectively. These two minerals constitute approximately 65 to 75 % of the mineral matrix. Matrix density values vary from 2.60 to 2.75 g/cc. Total porosity values obtained from nuclear logs range from 20 to 30 % and are consistent with those obtained from electrical logs ranging from 22 to 29 %. Together with the inherently low natural gamma radiation and the matrix density values obtained from other nuclear logging measurements, this indicates that at Kappelen site the aquifer is essentially devoid of clay. Hydraulic conductivity values obtained by the Dilution Technique vary between 3.10-4 and 5.10-2 m/s, while pumping tests give values ranging from 10-4 to 10-2 m/s. Grain size analysis of gravel samples collected from boreholes cores reveal significant granulometric heterogeneity of these deposits. Calculations based on these granulometric data have shown that the sand-, silt- and shale-sized fractions constitute between 10 and 40 % of the sample mass. The presence of these fine elements in general and their spatial distribution in particular are important as they largely control the distribution of the total and effective porosity as well as the hydraulic conductivity. Effective porosity values ranging from 11 to 25% estimated from grain size analyses indicate that the zones of higher hydraulic conductivity values correspond to the zones dominated by gravels. The methodology established at the Kappelen site was then applied to the Grenchen site. Results from surface-based geoelectric measurements indicate that it is a confined aquifer made up predominantly of shaly sands with intercalated sand lenses confined impermeable shally clay. The Grenchen confined aquifer has a relatively tabular and horizontal structure with a maximum thickness of 25 m in the south and the southwest with important sand passages. Petrophysical and hydrological characteristics were performed using electrical and nuclear logging. Natural gamma radiation values ranging from 30 to 100 cps indicate presence of a clay fraction but not of pure clay layers. Total porosity values obtained from electrical logs vary form 25 to 42%, whereas those obtained from nuclear logs values vary from 15 to 25%. This over-estimation confirms presences of clays. Density values obtained from nuclear logs varying from 2.25 to 2.45 g/cc in conjunction with the total porosity values indicate that the dominating matrix minerals are quartz and calcite. Matrix density values vary between 2.65 and 2.75 g/cc. Hydraulic conductivity values obtained by the Dilution Technique vary from 2 10-6 to 5 10-4 m/s.
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This thesis gives an overview of the validation process for thermal hydraulic system codes and it presents in more detail the assessment and validation of the French code CATHARE for VVER calculations. Three assessment cases are presented: loop seal clearing, core reflooding and flow in a horizontal steam generator. The experience gained during these assessment and validation calculations has been used to analyze the behavior of the horizontal steam generator and the natural circulation in the geometry of the Loviisa nuclear power plant. The cases presented are not exhaustive, but they give a good overview of the work performed by the personnel of Lappeenranta University of Technology (LUT). Large part of the work has been performed in co-operation with the CATHARE-team in Grenoble, France. The design of a Russian type pressurized water reactor, VVER, differs from that of a Western-type PWR. Most of thermal-hydraulic system codes are validated only for the Western-type PWRs. Thus, the codes should be assessed and validated also for VVER design in order to establish any weaknesses in the models. This information is needed before codes can be used for the safety analysis. Theresults of the assessment and validation calculations presented here show that the CATHARE code can be used also for the thermal-hydraulic safety studies for VVER type plants. However, some areas have been indicated which need to be reassessed after further experimental data become available. These areas are mostly connected to the horizontal stem generators, like condensation and phase separation in primary side tubes. The work presented in this thesis covers a large numberof the phenomena included in the CSNI code validation matrices for small and intermediate leaks and for transients. Also some of the phenomena included in the matrix for large break LOCAs are covered. The matrices for code validation for VVER applications should be used when future experimental programs are planned for code validation.
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The future of high technology welded constructions will be characterised by higher strength materials and improved weld quality with respect to fatigue resistance. The expected implementation of high quality high strength steel welds will require that more attention be given to the issues of crack initiation and mechanical mismatching. Experiments and finite element analyses were performed within the framework of continuum damage mechanics to investigate the effect of mismatching of welded joints on void nucleation and coalescence during monotonic loading. It was found that the damage of undermatched joints mainly occurred in the sandwich layer and the damageresistance of the joints decreases with the decrease of the sandwich layer width. The damage of over-matched joints mainly occurred in the base metal adjacent to the sandwich layer and the damage resistance of the joints increases with thedecrease of the sandwich layer width. The mechanisms of the initiation of the micro voids/cracks were found to be cracking of the inclusions or the embrittled second phase, and the debonding of the inclusions from the matrix. Experimental fatigue crack growth rate testing showed that the fatigue life of under-matched central crack panel specimens is longer than that of over-matched and even-matched specimens. Further investigation by the elastic-plastic finite element analysis indicated that fatigue crack closure, which originated from the inhomogeneousyielding adjacent to the crack tip, played an important role in the fatigue crack propagation. The applicability of the J integral concept to the mismatched specimens with crack extension under cyclic loading was assessed. The concept of fatigue class used by the International Institute of Welding was introduced in the parametric numerical analysis of several welded joints. The effect of weld geometry and load condition on fatigue strength of ferrite-pearlite steel joints was systematically evaluated based on linear elastic fracture mechanics. Joint types included lap joints, angle joints and butt joints. Various combinations of the tensile and bending loads were considered during the evaluation with the emphasis focused on the existence of both root and toe cracks. For a lap joint with asmall lack-of-penetration, a reasonably large weld leg and smaller flank angle were recommended for engineering practice in order to achieve higher fatigue strength. It was found that the fatigue strength of the angle joint depended strongly on the location and orientation of the preexisting crack-like welding defects, even if the joint was welded with full penetration. It is commonly believed that the double sided butt welds can have significantly higher fatigue strength than that of a single sided welds, but fatigue crack initiation and propagation can originate from the weld root if the welding procedure results in a partial penetration. It is clearly shown that the fatigue strength of the butt joint could be improved remarkably by ensuring full penetration. Nevertheless, increasing the fatigue strength of a butt joint by increasing the size of the weld is an uneconomical alternative.
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Magneto-active polymers are a class of smart materials commonly manufactured by mixing micron-sized iron particles in a rubber-like matrix. When cured in the presence of an externally applied magnetic field, the iron particles arrange themselves into chain-like structures that lend an overall anisotropy to the material. It has been observed through electron micrographs and X-ray tomographs that these chains are not always perfect in structure, and may have dispersion due to the conditions present during manufacturing or some undesirable material properties. We model the response of these materials to coupled magneto-mechanical loading in this paper using a probability based structure tensor that accounts for this imperfect anisotropy. The response of the matrix material is decoupled from the chain phase, though still being connected through kinematic constraints. The latter is based on the definition of a 'chain deformation gradient' and a 'chain magnetic field'. We conclude with numerical examples that demonstrate the effect of chain dispersion on the response of the material to magnetoelastic loading.
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An analytical approach for the interpretation of multicomponent heterogeneous adsorption or complexation isotherms in terms of multidimensional affinity spectra is presented. Fourier transform, applied to analyze the corresponding integral equation, leads to an inversion formula which allows the computation of the multicomponent affinity spectrum underlying a given competitive isotherm. Although a different mathematical methodology is used, this procedure can be seen as the extension to multicomponent systems of the classical Sips’s work devoted to monocomponent systems. Furthermore, a methodology which yields analytical expressions for the main statistical properties (mean free energies of binding and covariance matrix) of multidimensional affinity spectra is reported. Thus, the level of binding correlation between the different components can be quantified. It has to be highlighted that the reported methodology does not require the knowledge of the affinity spectrum to calculate the means, variances, and covariance of the binding energies of the different components. Nonideal competitive consistent adsorption isotherm, widely used in metal/proton competitive complexation to environmental macromolecules, and Frumkin competitive isotherms are selected to illustrate the application of the reported results. Explicit analytical expressions for the affinity spectrum as well as for the matrix correlation are obtained for the NICCA case. © 2004 American Institute of Physics.
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Comparative analysis of gene fragments of six housekeeping loci, distributed around the two chromosomes of Vibrio cholerae, has been carried out for a collection of 29 V. cholerae O139 Bengal strains isolated from India during the first epidemic period (1992 to 1993). A toxigenic O1 ElTor strain from the seventh pandemic and an environmental non-O1/non-O139 strain were also included in this study. All loci studied were polymorphic, with a small number of polymorphic sites in the sequenced fragments. The genetic diversity determined for our O139 population is concordant with a previous multilocus enzyme electrophoresis study in which we analyzed the same V. cholerae O139 strains. In both studies we have found a higher genetic diversity than reported previously in other molecular studies. The results of the present work showed that O139 strains clustered in several lineages of the dendrogram generated from the matrix of allelic mismatches between the different genotypes, a finding which does not support the hypothesis previously reported that the O139 serogroup is a unique clone. The statistical analysis performed in the V. cholerae O139 isolates suggested a clonal population structure. Moreover, the application of the Sawyer's test and split decomposition to detect intragenic recombination in the sequenced gene fragments did not indicate the existence of recombination in our O139 population.
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Diplomityössä luodaan viitekehys tuotetiedonhallintajärjestelmän esisuunnittelua varten. Siinä on kolme ulottuvuutta: lisäarvontuotto-, toiminnallisuus- ja ohjelmistoulottuvuus. Viitekehys auttaa- tunnistamaan lisäarvontuottokomponentit, joihin voidaan vaikuttaa tiettyjen ohjelmistoluokkien tarjoamilla tuotetiedonhallintatoiminnallisuuksilla. Viitekehyksen järjestelmäsuunnittelullista näkökulmaa hyödynnetään tutkittavissa yritystapauksissa perustuen laskentamatriisin muotoon mallinnettuihin ulottuvuuksien välisiin suhteisiin. Matriisiin syötetään lisäarvontuotto- ja toiminnallisuuskomponenttien saamat tärkeydet kohdeyrityksessä suoritetussa haastattelututkimuksessa. Matriisin tuotos on tietyn ohjelmiston soveltuvuus kyseisen yrityksen tapauksessa. Soveltuvuus on joukko tunnuslukuja, jotka analysoidaan tulostenkäsittelyvaiheessa. Soveltuvuustulokset avustavat kohdeyritystä sen valitessa lähestymistapaansa tuotetiedonhallintaan - ja kuvaavat esisuunnitellun tuotetiedonhallintajärjestelmän. Viitekehyksen rakentaminen vaatii perinpohjaisen lähestymistavan merkityksellisten lisäarvontuotto- ja toiminnallisuuskomponenttien sekä ohjelmistoluokkien määrittämiseen. Määritystyö perustuu työssä yksityiskohtaisesti laadittujen menetelmien ja komponenttiryhmitysten hyödyntämiselle. Kunkin alueen analysointi mahdollistaa viitekehyksen ja laskentamatriisin rakentamisen yhdenmukaisten määritysten perusteella. Viitekehykselle on ominaista sen muunneltavuus. Nykymuodossaan se soveltuu elektroniikka- ja high-tech yrityksille. Viitekehystä voidaan hyödyntää myös muilla toimialoilla muokkaamalla lisäarvontuottokomponentteja kunkin toimialan intressien mukaisesti. Vastaavasti analysoitava ohjelmisto voidaan valita tapauskohtaisesti. Laskentamatriisi on kuitenkin ensin päivitettävä valitun ohjelmiston kyvykkyyksillä, minkä jälkeen viitekehys voi tuottaa soveltuvuustuloksia kyseiseen yritystapaukseen perustuen
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Työn tavoitteena oli kehittää kunnossapitoyritykselle toiminnan tuottavuuden ja tehokkuuden mittausjärjestelmä. Ensin etsittiin teorian avulla ne sopivat suorituskykymittarit ja tekijät, joiden avulla yrityksen suorituskykyä voidaan luotettavasti ja ymmärrettävästi seurata. Apuna työnkulussa käytettiin kunnossapidon henkilökunnalle suunnattuja kirjallisia ja suullisia haastatteluja. Haastatteluiden avulla selvitettiin kunnossapidon suorituskyvyn mittauksen nykytila sekä mahdollisia kehityskohteita. Haastatteluihin ja kirjallisuuteen pohjautuen päätettiin yritykselle rakentaa suorituskykymittaristo. Mittaristoksi valittiin tuottavuus- eli tavoitematriisi, joka on toimiva työkalu mittareiden seurantaan. Se on helppokäyttöinen ja selkeä. Lisäksi matriisi antaa tulosindeksin avulla kokonaiskuvan kunnossapidon tasosta. Tavoitematriisi koostuu eri menestystekijöistä sekä näiden menestystekijöiden tunnusluvuista eli mittareista. Menestystekijöiksi valittiin: taloudellisuus, tuotantojärjestelmän tehokkuus, kustannusrakenne, kunnossapidon suunnittelu sekä häiriönkorjaus. Menestystekijöillä on jokaisella kolmesta kuuteen mittaria. Tavoitematriisin käyttö ja seuranta tapahtuu yksinkertaisen sovellusohjelman avulla. Mittariston kehittäminen on pitkä ja vaativa prosessi. Mittareita, niiden tavoitearvoja sekä menestystekijöitä tulee säännöllisin väliajoin tarkastaa, jotta kehitys on oikean suuntaista. Mittariston käyttöönotto ja käyttö edellyttävät kaikilta työntekijöiltä motivaatiota toiminnan kehitykseen sekä pitkäjänteisyyttä, sillä matriisin tarjoamat hyödyt ovat näkyvissä vasta kuukausien päästä.
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A statistical indentation method has been employed to study the hardness value of fire-refined high conductivity copper, using nanoindentation technique. The Joslin and Oliver approach was used with the aim to separate the hardness (H) influence of copper matrix, from that of inclusions and grain boundaries. This approach relies on a large array of imprints (around 400 indentations), performed at 150 nm of indentation depth. A statistical study using a cumulative distribution function fit and Gaussian simulated distributions, exhibits that H for each phase can be extracted when the indentation depth is much lower than the size of the secondary phases. It is found that the thermal treatment produces a hardness increase, due to the partly re-dissolution of the inclusions (mainly Pb and Sn) in the matrix.
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Successful generation of high producing cell lines requires the generation of cell clones expressing the recombinant protein at high levels and the characterization of the clones' ability to maintain stable expression levels. The use of cis-acting epigenetic regulatory elements that improve this otherwise long and uncertain process has revolutionized recombinant protein production. Here we review and discuss new insights into the molecular mode of action of the matrix attachment regions (MARs) and ubiquitously-acting chromatin opening elements (UCOEs), i.e. cis-acting elements, and how these elements are being used to improve recombinant protein production. These elements can help maintain the chromatin environment of the transgene genomic integration locus in a transcriptionally favorable state, which increases the numbers of positive clones and the transgene expression levels. Moreover, the high producing clones tend to be more stable in long-term cultures even in the absence of selection pressure. Therefore, by increasing the probability of isolating a high producing clone, as well as by increasing transcription efficiency and stability, these elements can significantly reduce the time and cost required for producing large quantities of recombinant proteins.
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Fabrication of new optical devices based upon the incorporation of rare earth ions via sol-gel methods depends on elimination of dopant ion clusters and residual hydroxyl groups from the final material. The optical absorption and/or luminescence properties of luminescent rare earth ions are influenced by the local bonding environment and the distribution of the rare-earth dopants in the matrix. Typically, dopants are incorporated into gel via dissolution of soluble species into the initial precursor sol. In this work, Eu3+ is used as optical probe, to assess changes in the local environment. Results of emission, excitation, fluorescence line narrowing and lifetimes studies of Eu3+-doped gels derived from Si(OCH3)4 and fluorinated/chelate Eu3+ precursors are presented. The precursors used in the sol-gel synthesis were: tris (6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate) Eu(III), Eu (III) trifluoromethanesulfonate, Eu(III) acetylacetonate hydrate, Eu (III) trifluoroacetate trihidrate, tris (2,2,6,6-tetramethyl-3,5- heptanedionate) Eu(III) and Eu(NO3)3.6H2O. The results were interpreted in terms of the evolution of the Eu3+ fluorescence in systems varying from solution to the gels densified to 800ºC. The lifetimes studies indicate that the fluorinated precursors are effective at reducing the water content in densified gels.
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ELISAs have been applied to pesticide residue analysis due to their high sensitivity and selectivity. However, some ELISAs performance may be affected by matrix components. In this work, ELISA for carbaryl in water samples was checked for interference by naturally occurring fulvic acids. The results suggested that the high fulvic acid concentration (³30 mg L-1) and acidic pH conditions (pH 4.0) interfere with the signal detection decreasing the method sensitivity. A dilution of the samples and adjust to pH 8.0 are appropriate to minimize the matrix interferences in the ELISA method. Good correlation between ELISA and HPLC-DAD results was observed.