994 resultados para Clock Drawing test


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Water is vital to humans and each of us needs at least 1.5 L of safe water a day to drink. Beginning as long ago as 1958 the World Health Organization (WHO) has published guidelines to help ensure water is safe to drink. Focused from the start on monitoring radionuclides in water, and continually cooperating with WHO, the International Standardization Organization (ISO) has been publishing standards on radioactivity test methods since 1978. As reliable, comparable and"fit for purpose" results are an essential requirement for any public health decision based on radioactivity measurements, international standards of tested and validated radionuclide test methods are an important tool for production of such measurements. This paper presents the ISO standards already published that could be used as normative references by testing laboratories in charge of radioactivity monitoring of drinking water as well as those currently under drafting and the prospect of standardized fast test methods in response to a nuclear accident.

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Työssä esisuunniteltiin Kemira Pigments Oy:lle uusi titanyylisulfaatin elektrolyyttinen pelkistyslaitos. Suurin syy uuden laitoksen suunnitteluun oli nykyisen laitoksen aiheuttamat korkeat H2SO4-pitoisuudet pelkistyslaitoksen läheisyydessä. Työn kirjallisuusosassa käsitellään elektrolyysilaitteiston suunnitteluun liittyviä seikkoja ja esitellään titanyylisulfaatin elektrolyyttiseen pelkistykseen liittyvää tutkimustietoa. Ennen uuden laitoksen suunnittelua suoritettiin nykyisellä pelkistyslaitoksella koeajoja, joiden tarkoituksena oli antaa lähtötiedot uuden laitoksen suunnittelulle. Koeajot osoittivat mm., että pelkistys on edullisinta suorittaa alhaisella virrantiheydellä n. 300…400 A/m2 ja vesilaimennuksen avulla anolyytin H2SO4-pitoisuus saadaan säädettyä tasolle, jossa titaani ei saostu. Kärynpoistoyhteisiin asennettujen pesuvesisuuttimien avulla saatiin titaanin saostuminen kärynpoistokanaviin estettyä. Uudesta titanyylisulfaatin elektrolyyttisestä pelkistyslaitoksesta laadittiin mm. seuraavat dokumentit: prosessin virtauskaavio ja ainevirtakenttä, PI-kaavio, layout-kuvat laitoksesta ja sen sijoituksesta sekä rakennepiirros elektrolyysialtaasta. Hankkeelle tehtiin kustannusarvio tarkkuudella ±20 %, jonka loppusummaksi saatiin 1 489 000 €. Laitoksen vuotuisten käyttökustannuksien arvioitiin olevan n. 105 000 €. Investoinnista aiheutuvien vuotuisten annuiteettikustannusten arvioitiin olevan n. 237 000 € 16,3 % korolla.

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Mayflies (Ephemeroptera) are known to generally present a high degree of insular endemism: half of the 28 species known from Corsica and Sardinia are considered as endemic. We sequenced the DNA barcode (a fragment of the mitochondrial COI gene) of 349 specimens from 50 localities in Corsica, Sardinia, continental Europe and North Africa. We reconstructed gene trees of eight genera or species groups representing the main mayfly families. Alternative topologies were built to test if our reconstructions suggested a single or multiple Corsican/Sardinian colonization event(s) in each genus or species group. A molecular clock calibrated with different evolution rates was used to try to link speciation processes with geological events. Our results confirm the high degree of endemism of Corsican and Sardinian mayflies and the close relationship between these two faunas. Moreover, we have evidence that the mayfly diversity of the two islands is highly underestimated as at least six new putative species occur on the two islands. We demonstrated that the Corsican and Sardinian mayfly fauna reveals a complex history mainly related to geological events. The Messinian Salinity Crisis, which is thought to have reduced marine barriers, thus facilitating gene flow between insular and continental populations, was detected as the most important event in the speciation of most lineages. Vicariance processes related to the split and rotation of the Corso-Sardinian microplate had a minor impact as they involved only two genera with limited dispersal and ecological range. Colonization events posterior to the Messinian Salinity Crisis had only marginal effects as we had indication of recent gene flow only in two clades. With very limited recent gene flow and a high degree of endemism, mayflies from Corsica and Sardinia present all the criteria for conservation prioritization.

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By means of computer simulations and solution of the equations of the mode coupling theory (MCT),we investigate the role of the intramolecular barriers on several dynamic aspects of nonentangled polymers. The investigated dynamic range extends from the caging regime characteristic of glass-formers to the relaxation of the chain Rouse modes. We review our recent work on this question,provide new results, and critically discuss the limitations of the theory. Solutions of the MCT for the structural relaxation reproduce qualitative trends of simulations for weak and moderate barriers. However, a progressive discrepancy is revealed as the limit of stiff chains is approached. This dis-agreement does not seem related with dynamic heterogeneities, which indeed are not enhanced by increasing barrier strength. It is not connected either with the breakdown of the convolution approximation for three-point static correlations, which retains its validity for stiff chains. These findings suggest the need of an improvement of the MCT equations for polymer melts. Concerning the relaxation of the chain degrees of freedom, MCT provides a microscopic basis for time scales from chain reorientation down to the caging regime. It rationalizes, from first principles, the observed deviations from the Rouse model on increasing the barrier strength. These include anomalous scaling of relaxation times, long-time plateaux, and nonmonotonous wavelength dependence of the mode correlators.

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Endothelial cell release of nitric oxide (NO) is a defining characteristic of nondiseased arteries, and abnormal endothelial NO release is both a marker of early atherosclerosis and a predictor of its progression and future events. Healthy coronaries respond to endothelial-dependent stressors with vasodilatation and increased coronary blood flow (CBF), but those with endothelial dysfunction respond with paradoxical vasoconstriction and reduced CBF. Recently, coronary MRI and isometric handgrip exercise (IHE) were reported to noninvasively quantify coronary endothelial function (CEF). However, it is not known whether the coronary response to IHE is actually mediated by NO and/or whether it is reproducible over weeks. To determine the contribution of NO, we studied the coronary response to IHE before and during infusion of N(G)-monomethyl-l-arginine (l-NMMA, 0.3 mg·kg(-1)·min(-1)), a NO-synthase inhibitor, in healthy volunteers. For reproducibility, we performed two MRI-IHE studies ∼8 wk apart in healthy subjects and patients with coronary artery disease (CAD). Changes from rest to IHE in coronary cross-sectional area (%CSA) and diastolic CBF (%CBF) were quantified. l-NMMA completely blocked normal coronary vasodilation during IHE [%CSA, 12.9 ± 2.5 (mean ± SE, placebo) vs. -0.3 ± 1.6% (l-NMMA); P < 0.001] and significantly blunted the increase in flow [%CBF, 47.7 ± 6.4 (placebo) vs. 10.6 ± 4.6% (l-NMMA); P < 0.001]. MRI-IHE measures obtained weeks apart strongly correlated for CSA (P < 0.0001) and CBF (P < 0.01). In conclusion, the normal human coronary vasoactive response to IHE is primarily mediated by NO. This noninvasive, reproducible MRI-IHE exam of NO-mediated CEF promises to be useful for studying CAD pathogenesis in low-risk populations and for evaluating translational strategies designed to alter CAD in patients.

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Differentiation between photoallergenic and phototoxic reactions induced by low molecular weight compounds represents a current problem. The use of eratinocytes as a potential tool for the detection of photoallergens as opposed to photoirritants is considered an interesting strategy for developing in vitro methods. We have previously demonstrated the possibility to use the human keratinocyte cell line NCTC2455 and the production of interleukin-18 (IL-18) to screen low molecular weight sensitizers. The purpose of this work was to explore the possibility to use the NCTC2544 assay to identify photoallergens and discriminate from phototoxic chemicals. First, we identified suitable condition of UV-irradiation (3.5 J/cm2) by investigating the effect of UVAirradiation on intracellular IL-18 on untreated or chloropromazine (a representative phototoxic compound)- treated NCTC2544 cells. Then, the effect of UVA-irradiation over NCTC2544 cells treated with increasing concentrations of 15 compounds including photoallergens (benzophenone, 4-ter-butyl-4-methoxydibenzoylmethane, 2-ethylexyl-p-methoxycinnamate, ketoprofen, 6-methylcumarin); photoirritant and photoallergen (4-aminobenzoic acid, chlorpromazine, promethazine); photoirritants (acridine, ibuprofen, 8-methoxypsoralen, retinoic acid); and negative compounds (lactic acid, SDS and p-phenilendiamine) was investigated. Twenty-four hours after exposure, cytotoxicity was evaluated by the MTT assay or LDH leakage, while ELISA was used to measure the production of IL-18. At the maximal concentration assayed with non-cytotoxic effects (CV80 under irradiated condition), all tested photoallergens induced a significant and a dose-dependent increase of intracellular IL-18 following UVA irratiation, whereas photoirritants failed. We suggest that this system may be useful for the in vitro evaluation of the photoallergic potential of chemicals.

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Cette thèse porte sur la contribution des caractéristiques individuelles et des situations professionnelles au bien-être. En combinant différentes perspectives théoriques, notamment la théorie de la construction de la carrière, la théorie de la justice organisationnelle, les modèles du bien-être au travail, et les conceptualisations de l'incivilité au travail, un certain nombre d'hypothèses sont proposées concernant le lien entre certaines caractéristiques individuelles et situationnelles et le bien-être général et professionnel. Les deux premières études se focalisent sur la validation d'une échelle d'adaptabilités de carrière et sur le rôle médiateur de cette adaptabilité dans la relation entre des dispositions et le bien-être. La troisième étude évolue l'hypothèse d'un possible effet de médiation de l'adaptabilité mais cette fois de la relation entre insécurité professionnelle et charge de travail d'une part et le bien-être d'autre part. La quatrième étude adopte une perspective longitudinale et analyse les associations entre les dimensions de la personnalité, l'adaptabilité de carrière et le bien-être dans quatre parcours professionnels différents. La cinquième étude porte sur une autre caractéristique individuelle, à savoir la croyance en un monde juste. Cette étude illustre comment la croyance en un monde juste influence les perceptions de justice organisationnelle une année après, qui ont une incidence importante sur le bien-être. Enfin, la dernière étude se concentre sur une population spécifique, les immigrants en Suisse, et souligne qu'être la cible d'incivilité sur le lieu de travail est généralement liée au pays d'origine. Globalement, cette thèse met en évidence que les caractéristiques individuelles ont des effets tant directs qu'indirects sur le bien-être et que ces mêmes caractéristiques explique en partie, les relations entre la situation professionnelle et le bien-être. Plus spécifiquement, des situations professionnelles peuvent influencer l'expression de certaines caractéristiques individuelles, soit en contribuant à leurs activations ou à leurs inhibitions. De plus, l'impact des caractéristiques individuelles sur le bien-être semble dépendre de la situation professionnelle. Il est donc important de considérer les influences simultanées et réciproques des caractéristiques individuelles et de la situation contextuelle et professionnelle pour rendre compte du bien-être général et professionnel. -- This thesis explores how individual characteristics and professional situations correspond to well-being. Drawing from various theoretical backgrounds, such as career construction theory, justice theory, models of job strain, and theories on subtle discrimination, a number of specific hypotheses are put forward pertaining to a selection of individual and professional aspects as well as general and work-related well-being. The six studies presented in this thesis focus on specific aspects and adopt different methodological and theoretical approaches. The first two studies concern the validation of the career adapt-abilities scale and test the potential of career adapt-abilities to mediate the relationship between dispositions and outcomes. The third study extends the hypothesis of career adapt-abilities as a mediator and finds that it mediates the effects of job insecurity and job strain on general and professional well-being. The fourth study adopts a longitudinal approach and tests the associations between personality traits and career adaptability and well-being in four different professional situations. Study five concerns another individual characteristic, belief in a just world, and illustrates how justice beliefs drive perceptions of organizational justice, which in turn impact, on well-being outcomes one year later. The final study focuses on the professional experiences of a specific population, immigrants in Switzerland, and confirms that being a target of incivilities is related to national origin. Globally, this thesis finds that individual characteristics have direct and indirect influences on well-being and that these characteristics may also mediate the associations between professional situations and outcomes. In particular, the professional situation may alter the display of individual characteristics, either by contributing to their activation or their depletion, and the ways in which individual factors influence well-being does seem to depend on the professional situation. It is thus necessary to adopt a "both...and" perspective when studying the impact of individual and professional characteristics as these factors mutually influence each other.

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Suunniteltiin ja rakennettiin suoraa vääntömomenttisäätöä soveltava taajuudenmuuttajakäyttö oikosulkumoottorin ohjaukseen korvaamaan passiivinen jarrukäyttö. Laite on kuntoutuslaite, jolla tehdään lihasvoiman mittauksia ja voimaharjoituksia. Selvitettiin kaupallisten moottoreiden ja taajuudenmuuttajien suoritusominaisuuksia ja tämän perusteella valittiin käyttöön sopivat laitteet. Työssä esitetään kaksi oikosulkumoottorin ohjaustapaa: vektorisäätö ja suora vääntömomenttisäätö. Merkittävin osa tästä työstä käsittelee - tarkan turvallisuussuunnitelman lisäksi - kuntoutuslaitteen prototyypin komponentteja, kokoamista ja suoritustestien tuloksia.

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BACKGROUND: Best corrected visual acuity (BCVA) of 0.8 or above in AMD patients can sometimes correspond to poor macular function inducing a serious visual handicap. Microperimetry can be used to objectivize this difference. PATIENTS AND METHODS: A retrospective study was undertaken on 233 files of AMD patients of whom 82 had had a microperimetry. BCVA was compared with microperimetry performance. All examinations were performed in an identical setting by the same team of 3 persons. RESULTS: Among the 82 patients included, 32 (39.0%) had a BCVA equal to or above 0.8 even though their microperimetry performance was lower than 200/560 db. 10 of them (12.2% of total) had an even poorer microperimetry below 120/560 db indicating poor macular function. CONCLUSIONS: More than a third of the AMD patients had a bad or very bad microperimetry performance in parallel with a good visual acuity. Microperimetry is a valuable tool to assess and follow real macular function in AMD patients when visual acuity alone can be misleading.

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Introducción. Uno de los paradigmas más utilizados en el estudio de la atención es el Continuous Performance Test (CPT). La versión de pares idénticos (CPT-IP) se ha utilizado ampliamente para evaluar los déficits de atención en los trastornos del neurodesarrollo, neurológicos y psiquiátricos. Sin embargo, la localización de la activación cerebral de las redes atencionales varía significativamente según el diseño de resonancia magnética funcional (RMf) usado. Objetivo. Diseñar una tarea para evaluar la atención sostenida y la memoria de trabajo mediante RMf para proporcionar datos de investigación relacionados con la localización y el papel de estas funciones. Sujetos y métodos. El estudio contó con la participación de 40 estudiantes, todos ellos diestros (50%, mujeres; rango: 18-25 años). La tarea de CPT-IP se diseñó como una tarea de bloques, en la que se combinaban los períodos CPT-IP con los de reposo. Resultados. La tarea de CPT-IP utilizada activa una red formada por regiones frontales, parietales y occipitales, y éstas se relacionan con funciones ejecutivas y atencionales. Conclusiones. La tarea de CPT-IP utilizada en nuestro trabajo proporciona datos normativos en adultos sanos para el estudio del sustrato neural de la atención sostenida y la memoria de trabajo. Estos datos podrían ser útiles para evaluar trastornos que cursan con déficits en memoria de trabajo y en atención sostenida.