934 resultados para soft lens
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Aiming the establishment of simple and accurate readings of citric acid (CA) in complex samples, citrate (CIT) selective electrodes with tubular configuration and polymeric membranes plus a quaternary ammonium ion exchanger were constructed. Several selective membranes were prepared for this purpose, having distinct mediator solvents (with quite different polarities) and, in some cases, p-tert-octylphenol (TOP) as additive. The latter was used regarding a possible increase in selectivity. The general working characteristics of all prepared electrodes were evaluated in a low dispersion flow injection analysis (FIA) manifold by injecting 500µl of citrate standard solutions into an ionic strength (IS) adjuster carrier (10−2 mol l−1) flowing at 3ml min−1. Good potentiometric response, with an average slope and a repeatability of 61.9mV per decade and ±0.8%, respectively, resulted from selective membranes comprising additive and bis(2-ethylhexyl)sebacate (bEHS) as mediator solvent. The same membranes conducted as well to the best selectivity characteristics, assessed by the separated solutions method and for several chemical species, such as chloride, nitrate, ascorbate, glucose, fructose and sucrose. Pharmaceutical preparations, soft drinks and beers were analyzed under conditions that enabled simultaneous pH and ionic strength adjustment (pH = 3.2; ionic strength = 10−2 mol l−1), and the attained results agreed well with the used reference method (relative error < 4%). The above experimental conditions promoted a significant increase in sensitivity of the potentiometric response, with a supra-Nernstian slope of 80.2mV per decade, and allowed the analysis of about 90 samples per hour, with a relative standard deviation <1.0%.
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It is generally challenging to determine end-to-end delays of applications for maximizing the aggregate system utility subject to timing constraints. Many practical approaches suggest the use of intermediate deadline of tasks in order to control and upper-bound their end-to-end delays. This paper proposes a unified framework for different time-sensitive, global optimization problems, and solves them in a distributed manner using Lagrangian duality. The framework uses global viewpoints to assign intermediate deadlines, taking resource contention among tasks into consideration. For soft real-time tasks, the proposed framework effectively addresses the deadline assignment problem while maximizing the aggregate quality of service. For hard real-time tasks, we show that existing heuristic solutions to the deadline assignment problem can be incorporated into the proposed framework, enriching their mathematical interpretation.
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Multifocal intraocular lenses (MF IOLs) have concentric optical zones with different dioptric power, enabling patients to have good visual acuity at multiple focal points. However, several optical limitations have been attributed to this particular design. The purpose of this study is to access the effect of MF IOLs design on the accuracy of retinal optical coherence tomography (OCT). Cross-sectional study conducted at the Refractive Surgery Department of Central Lisbon Hospital Center. Twenty-three eyes of 15 patients with a diffractive MF IOL and 27 eyes of 15 patients with an aspheric monofocal IOL were included in this study. All patients underwent OCT macular scans using Heidelberg Spectralis®. Macular thickness and volume values and image quality (Q factor) were compared between the two groups. There were no statistically significant differences between both groups regarding macular thickness or volume measurements. Retinal OCT image quality was significantly lower in the MF IOL group (p < 0.01). MF IOLs are associated with a significant decrease in OCT image quality. However, this fact does not seem to compromise the accuracy of spectral domain OCT retinal measurements.
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Soft tissue sarcomas (STS) with complex genomic profiles (50% of all STS) are predominantly composed of spindle cell/pleomorphic sarcomas, including leiomyosarcoma, myxofibrosarcoma, pleomorphic liposarcoma, pleomorphic rhabdomyosarcoma, malignant peripheral nerve sheath tumor, angiosarcoma, extraskeletal osteosarcoma, and spindle cell/pleomorphic unclassified sarcoma (previously called spindle cell/pleomorphic malignant fibrous histiocytoma). These neoplasms show, characteristically, gains and losses of numerous chromosomes or chromosome regions, as well as amplifications. Many of them share recurrent aberrations (e.g., gain of 5p13-p15) that seem to play a significant role in tumor progression and/or metastatic dissemination. In this paper, we review the cytogenetic, molecular genetic, and clinicopathologic characteristics of the most common STS displaying complex genomic profiles. Features of diagnostic or prognostic relevance will be discussed when needed.
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Segment poses and joint kinematics estimated from skin markers are highly affected by soft tissue artifact (STA) and its rigid motion component (STARM). While four marker-clusters could decrease the STA non-rigid motion during gait activity, other data, such as marker location or STARM patterns, would be crucial to compensate for STA in clinical gait analysis. The present study proposed 1) to devise a comprehensive average map illustrating the spatial distribution of STA for the lower limb during treadmill gait and 2) to analyze STARM from four marker-clusters assigned to areas extracted from spatial distribution. All experiments were realized using a stereophotogrammetric system to track the skin markers and a bi-plane fluoroscopic system to track the knee prosthesis. Computation of the spatial distribution of STA was realized on 19 subjects using 80 markers apposed on the lower limb. Three different areas were extracted from the distribution map of the thigh. The marker displacement reached a maximum of 24.9mm and 15.3mm in the proximal areas of thigh and shank, respectively. STARM was larger on thigh than the shank with RMS error in cluster orientations between 1.2° and 8.1°. The translation RMS errors were also large (3.0mm to 16.2mm). No marker-cluster correctly compensated for STARM. However, the coefficient of multiple correlations exhibited excellent scores between skin and bone kinematics, as well as for STARM between subjects. These correlations highlight dependencies between STARM and the kinematic components. This study provides new insights for modeling STARM for gait activity.
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PURPOSE: To assess the agreement and repeatability of horizontal white-to-white (WTW) and horizontal sulcus-to-sulcus (STS) diameter measurements and use these data in combination with available literature to correct for interdevice bias in preoperative implantable collamer lens (ICL) size selection. DESIGN: Interinstrument reliability and bias assessment study. METHODS: A total of 107 eyes from 56 patients assessed for ICL implantation at our institution were included in the study. This was a consecutive series of all patients with suitable available data. The agreement and bias between WTW (measured with the Pentacam and BioGraph devices) and STS (measured with the HiScan device) were estimated. RESULTS: The mean spherical equivalent was -8.93 ± 5.69 diopters. The BioGraph measures of WTW were wider than those taken with the Pentacam (bias = 0.26 mm, P < .01), and both horizontal WTW measures were wider than the horizontal STS measures (bias >0.91 mm, P < .01). The repeatability (Sr) of STS measured with the HiScan was 0.39 mm, which was significantly reduced (Sr = 0.15 mm) when the average of 2 measures was used. Agreement between the horizontal WTW measures and horizontal STS estimates when bias was accounted for was г = 0.54 with the Pentacam and г = 0.64 with the BioGraph. CONCLUSIONS: Large interdevice bias was observed for WTW and STS measures. STS measures demonstrated poor repeatability, but the average of repeated measures significantly improved repeatability. In order to conform to the US Food and Drug Administration's accepted guidelines for ICL sizing, clinicians should be aware of and account for the inconsistencies between devices.
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Contient : 1 « Relation de la bataille de Lens, gaignée sur les Espagnols, le XXe d'aoust M.D.C.XLVIII, par LOUYS DE BOURBON, prince DE CONDE, et escritte de sa main » ; 2 « Liste des officiers de l'armée du roy mortz, blessez ou prisonniers en la bataille de Lens », le 20 août 1648 ; 3 « Liste des officiers de l'armée d'Espagne faictz prisonniers en la bataille de Lens, le 20 d'aoust 1648 » ; 4 « Lettre de Mr l'archiduc LEOPOLD à Mr l'eslecteur de Cologne... Le 22 aoust, en St Vicconi, 1648 »
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The nature of this research is to investigate paleoseismic deformation of glacial soft sediments from three sampling sites throughout the Scottish Highlands; Arrat's Mills, Meikleour and Glen Roy. The paleoseismic evidence investigated in this research will provide a basis for applying criteria to soft sediment deformation structures, and the trigger mechanisms that create these structures. Micromorphology is the tool used in this to investigate paleoseismic deformation structures in thin section. Thin section analysis, (micromorphology) of glacial sediments from the three sampling sites is used to determine microscale evidence of past earthquakes that can be correlated to modem-day events and possibly lead to a better understanding of the impact of earthquakes throughout a range of sediment types. The significance of the three sampling locations is their proximity to two major active fault zones that cross Scotland. The fault zones are the Highland Boundary Fault and the Great Glen Fault, these two major faults that parallel each other and divide the country in half Sims (1975) used a set of seven criteria that identified soft sediment deformation structures created by a magnitude six earthquake in Cahfomia. Using criteria set forth by Sims (1975), the paleoseismic evidence can be correlated to the magnitude of the deformation structures found in the glacial sediments. This research determined that the microstructures at Arrat's Mill, Meikleour and Glen Roy are consistent with a seismically induced origin. It has also been demonstrated that, even without the presence of macrostructures, the use of micromorphology techniques in detecting such activity within sediments is of immense value.
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Academic exchange programmes provide opportunities for teacher candidates to study at educational institutions abroad wherein they are able to learn more about different cultures, teaching practices, and build cross-cultural relationships. This paper is an exploration into my teacher candidate experience abroad. The relevant research on this topic indicates that teacher certification should take an active role in creating opportunities for teacher candidates to participate in educational experiences abroad because of their benefits. The knowledge that a teacher gains through abroad experiences is one of the strongest factors in helping to build authentic global classrooms. In addition, these programmes allow for fuller understanding of a global context and the chance to understand someone else’s story. This review and synthesis of literature and research findings prepares a foundation for how teacher candidates, and hopefully, how policy makers can work toward creating a more inclusive global classroom for students.
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Small, black, soft cover notebook which has “Niagara Historical Society” taped to the front cover. It contains handwritten entries which include: names of early settlers; buildings; veterans at Queenston Heights, 1859; group of Indians; and list of people whose picture was taken in 1870[?] at Queenston, n.d.
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Memoranda booklet (soft cover) compliments of the Canadian Bank of Commerce, St. Catharines Branch. Only one page has writing on it. It appears to be a shopping list, n.d.
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Département de linguistique et de traduction
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Controlled choice over public schools attempts giving options to parents while maintaining diversity, often enforced by setting feasibility constraints with hard upper and lower bounds for each student type. We demonstrate that there might not exist assignments that satisfy standard fairness and non-wastefulness properties; whereas constrained non-wasteful assignments which are fair for same type students always exist. We introduce a "controlled" version of the deferred acceptance algorithm with an improvement stage (CDAAI) that finds a Pareto optimal assignment among such assignments. To achieve fair (across all types) and non-wasteful assignments, we propose the control constraints to be interpreted as soft bounds-flexible limits that regulate school priorities. In this setting, a modified version of the deferred acceptance algorithm (DAASB) finds an assignment that is Pareto optimal among fair assignments while eliciting true preferences. CDAAI and DAASB provide two alternative practical solutions depending on the interpretation of the control constraints. JEL C78, D61, D78, I20.
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Le développement accéléré des technologies de communication, de saisie et de traitement de l’information durant les dernières années décennies ouvre la voie à de nouveaux moyens de contrôle social. Selon l’auteur Gary Marx ceux-ci sont de nature non coercitive et permettent à des acteurs privés ou publics d’obtenir des informations personnelles sur des individus sans que ceux-ci y consentent ou mêmes sans qu’ils en soient conscients. Ces moyens de contrôle social se fondent sur certaines valeurs sociales qui sont susceptibles de modifier le comportement des individus comme le patriotisme, la notion de bon citoyen ou le volontarisme. Tout comme les moyens coercitifs, elles amènent les individus à adopter certains comportements et à divulguer des informations précises. Toutefois, ces moyens se fondent soit sur le consentement des individus, consentement qui est souvent factice et imposée, soit l’absence de connaissance du processus de contrôle par les individus. Ainsi, l’auteur illustre comment des organisations privées et publiques obtiennent des informations privilégiées sur la population sans que celle-ci en soit réellement consciente. Les partisans de tels moyens soulignent leur importance pour la sécurité et le bien publique. Le discours qui justifie leur utilisation soutient qu’ils constituent des limites nécessaires et acceptables aux droits individuels. L’emploi de telles méthodes est justifié par le concept de l’intérêt public tout en minimisant leur impact sur les droits des individus. Ainsi, ces méthodes sont plus facilement acceptées et moins susceptibles d’être contestées. Toutefois, l’auteur souligne l’importance de reconnaître qu’une méthode de contrôle empiète toujours sur les droits des individus. Ces moyens de contrôle sont progressivement intégrés à la culture et aux modes de comportement. En conséquence, ils sont plus facilement justifiables et certains groupes en font même la promotion. Cette réalité rend encore plus difficile leur encadrement afin de protéger les droits individuels. L’auteur conclut en soulignant l’important décalage moral derrière l’emploi de ces méthodes non-coercitives de contrôle social et soutient que seul le consentement éclairé des individus peut justifier leur utilisation. À ce sujet, il fait certaines propositions afin d’encadrer et de rendre plus transparente l’utilisation de ces moyens de contrôle social.