124 resultados para pointer


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We develop criteria sufficient to enable detection of macroscopic coherence where there are not just two macroscopically distinct outcomes for a pointer measurement, but rather a spread of outcomes over a macroscopic range. The criteria provide a means to distinguish a macroscopic quantum description from a microscopic one based on mixtures of microscopic superpositions of pointer-measurement eigenstates. The criteria are applied to Gaussian-squeezed and spin-entangled states.

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Background: Paediatricians rely on cough descriptors to direct them to the level of investigations needed for a child presenting with chronic cough, yet there is a lack of published data to support this approach. A study was undertaken to evaluate ( 1) whether historical cough pointers can predict which children have a specific cause for their cough and ( 2) the usefulness of chest radiography and spirometry as standard investigations in children with chronic cough. Methods: This was a prospective cohort study of children referred to a tertiary hospital with a cough lasting 3 weeks between June 2002 and July 2004. All included children completed a detailed history and examination using a standardised data collection sheet and followed a pathway of investigation until a diagnosis was made. Results: In 100 consecutively recruited children of median age 2.8 years, the best predictor of specific cough observed was a moist cough at the time of consultation with an odds ratio ( OR) of 9.34 (95% CI 3.49 to 25.03). Chest examination or chest radiographic abnormalities were also predictive with OR 3.60 ( 95% CI 1.31 to 9.90) and 3.16 (95% CI 1.32 to 7.62), respectively. The most significant historical pointer for predicting a specific cause of the cough was a parental history of moist cough ( sensitivity 96%, specificity 26%, positive predictive value 74%). Conclusions: The most useful clinical marker in predicting specific cough is the presence of a daily moist cough. Both chest examination and chest radiographic abnormalities are also useful in predicting whether children have a specific cause of their cough.

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As organizações se encontram em meio a uma série de transformações na sociedade e no mundo empresarial de natureza estrutural e tecnológica. Essas mudanças relacionadas ao processo de globalização, cada vez mais constantes na vida organizacional implicam as organizações uma postura cada vez mais responsável tanto a nível organizacional quanto social. Em se tratando de adaptações organizacionais, o funcionário poderá ser mais exigido. Se a empresa precisa estar mais competitiva para continuar no mercado e resistir, há expectativa de uma maior capacidade produtiva. Nesse contexto de pressões constantes a todos da organização, a Qualidade de Vida no Trabalho passa ser destaque como um diferencial competitivo para organizações, que programam e usufruem de seus resultados. Porém, não se pode deixar de pensar que além de produzir, as empresas devem estar preocupadas no seu papel perante a sociedade, nesse item, entra a Responsabilidade Social Empresarial. As empresas são cobradas tanto como estas podem influir na degradação dos recursos naturais, como na sua ação de fazer algo a mais que contribua para sociedade. Esse assunto vem se expandindo devido à sua importante aplicabilidade e atualmente tem pautado algumas discussões no campo organizacional. Com base neste conceito, este estudo buscou analisar as possíveis relações existentes entre os programas de Qualidade de Vida no Trabalho QVT e Responsabilidade Social Empresarial - RSE considerando a satisfação de QVT dos indivíduos que participam dos programas de RSE nas empresas que adotam ambos os programas QVT e RSE. Optou-se em adotar um estudo de caso em associação com métodos quantitativos para aplicação do instrumento BPSO (96) e métodos qualitativos, entrevistas e observação do pesquisador. Concluiu-se que os Envolvidos em programas de RSE não apresentaram maior satisfação de QVT em relação ao grupo Não Participa . O fato da participação do funcionário em RSE não deve ser considerado como um indicador de QVT. O que pode ter influenciado nos resultados é o perfil da amostra, que se mostrou muito heterogêneo, onde estão presentes vários tipo de pessoas e cada um com uma expectativa diferente do empenho da empresa com sua Qualidade de Vida no Trabalho.

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Purpose: A retrospective study of longitudinal case histories, undertaken to establish the clinical and statistical characteristics of unilateral myopic anisometropia (UMA) amongst the juvenile and adolescent population at an optometric practice, is reported. UMA was defined as that specific refractive state where an unequivocally myopic eye is paired with a 'piano' [spherical equivalent refraction, (SER) = ±0.25 Dioptres (D)] companion eye. Methods: The clinical records of all patients aged <19 years on file at an established independent optometric practice were categorised as 'myopic' (SER ≤-0.50 D), 'hypermetropie' (≥+0.75 D) or 'emmetropic' (≥-0.37≤+0.62 D). Subsequently all juvenile patients matching the UMA criterion, together with a case-matched group of bilaterally myopic individuals, were selected as the comparative study populations. Results: A total of 14.4% (n = 21 of 146) of the juvenile myopic case histories were identified as cases of UMA. More than half of these UMA cases emerged between the ages of 11.5 and 13.5 years. There was a marked female gender bias. The linear gradient of the age-related mean refractive trend in the myopic eye of the UMA population was not statistically significantly different (p > 0.1) to that fitted to the ametropic progression recorded in either eye of the case-matched population of young bilateral myopes; uniquely the slope associated with the companion eye of UMA cases was statistically significantly (p < 0.025) less steep. Compared with bilateral myopes fewer cases of UMA required a refractive correction to relieve visual or asthenopic symptoms, and this initial correction was dispensed on average 1 year later (at age 12.7 years) in UMA patients. Conclusions: Individuals identified as demonstrating clinically-defined UMA can be considered as distinct but functionally normal cases on the continuum of human refractive error. However, any unilaterally-acting determining factor(s) underlying the genesis of the condition remain obscure. © 2004 The College of Optometrists.

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Mineralogical investigations have determined the sites of u and Th associated with two radioelement-enriched granites from different geological settings. In the Ririwai ring complex, Nigeria, the u- and Th-bearing accessories have been greatly affected by post-magmatic alteration of the biotite granite. Primary thorite, zircon and monazite were altered to Zr(±Y)-rich thorite, partially metamict zircon (enriched in Th, U, Y, P, Fe, Mn, Ca) and an unidentified LREE-phase respectively, by pervasive fluids which later precipitated Zr-rich coffinite. More intense, localised alteration and albitisation completely remobilised primary accessories and gave rise to a distinctive generation of haematite- and uranothorite-enriched zircon with clear, Hi-enriched rims and xenotime overgrowths. In the Ririwai lode, microclinisation and later greisenisation locally remobilised or altered zircon and deposited Y-ricl1 coffinite and Y(±Zr)-rich thorite which was overgrown by traces of xenotime and LREE-phase(s) of complex and variable composition. Compositions indicating extensive solid-solution among thorite, coffinite, xenotime and altered zircon are probably metastable and formed at low temperatures. The widespread occurrence of REE-rich fluorite suggests that F-complexing aided the mobility of REE, Y, U, Th and Zr during late-magmatic to post-magmatic alteration, while uranyl-carbonate complexing may have occurred during albitisation. The Caledonian, Helmsdale granite in northern Scotland has undergone pervasive and localised hydrothermal alteration associated with U enrichment. Zircon xenocrysts, primary sphene and apatite contain a small.proportion of this U which is largely adsorbed on to secondary iron-oxide, TiOand phyllosilicates.Additional sites for U in the overlying, Lower Devonian Ousdale arkose include coffinite, secondary uranyl phosphates, hydrocarbon and traces of xenotime and unidentified LREE-phases. U may have been leached from the granite and deposited in the arkose, along channelways associated with the Helmsdale fault, by convecting, hydrothermal fluids

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The recording of visual acuity using the Snellen letter chart is only a limited measure of the visual performance of an eye wearing a refractive aid. Qualitative in addition to quantitative information is required to establish such a parameter: spatial, temporal and photometric aspects must all be incorporated into the test procedure. The literature relating to the correction of ametropia by refractive aids was reviewed. Selected aspects of a comparison between the correction provided by spectacles and contact lenses were considered. Special attention was directed to soft hydrophilic contact lenses. Despite technological advances which have produced physiologically acceptable soft lenses, there still remain associated with this recent form of refractive aid unpredictable visual factors. Several techniques for vision assessment were described, and previous studies of visual performance were discussed. To facilitate the investigation of visual performance in a clinical environment, a new semi-automated system was described: this utilized the presentation of broken ring test stimuli on a television screen. The research project comprised two stages. Initial work was concerned with the validation of the television system, including the optimization of its several operational variables. The second phase involved the utilization of the system in an investigation of visual performance aspects of the first month of regular daily soft contact lens wear by experimentally-naive subjects. On the basis of the results of this work an ‘homoeostatic’ model has been proposed to represent the strategy which an observer adopts in order to optimize his visual performance with soft contact lenses.

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Purpose: Changes in refractive error are well documented over the typical human lifespan. However, a relatively neglected period of investigation appears to be during the late fourth decade; this is at the incipient phase of presbyopia (IP), where the amplitude of accommodation is much reduced and approaches the level where a first reading addition is anticipated. Significantly, informal clinical observation has suggested a low incidence of an unexpected abrupt increase in myopia during IP. Methods: We investigated this alleged myopic shift retrospectively by mapping the longitudinal refraction histories of normally-sighted 35-44years old British White patients previously examined in routine optometric practice. The refractive trends in the right eyes of healthy myopic subjects (spherical equivalent refraction, SER =-0.50D: N=39) were analysed relative to that point at which a first near dioptric addition was considered to be clinically useful. Results: A refractive change was evident in some subjects during IP; viz, an abrupt increase in myopic SER of between -0.50 and -0.75D. These individuals (N=8) represented 20% of the study population of myopic incipient presbyopes. Beyond the pivotal point of the first near addition the longitudinal refraction stabilized in these subjects. In contrast, and as the extent of the available longitudinal data would permit, the remaining myopic eyes maintained an approximately stable refractive trend throughout IP and beyond. Conclusions: The anatomical or physiological basis of this specific late (non-developmental) abrupt myopic refractive change is an intriguing issue. Axial (vitreous chamber elongation), corneal (contour) and lenticular (profile and index) power bases, alone or in concert, might be considered candidates for this hitherto unexplored refractive phenomenon. Although necessarily obtained under conventional conditions of central (0deg) fixation, our data might also be a reflection of the recent recognition of the possible influence of the peripheral refraction upon the axial error. Consideration of this material provides an impetus for further research, including ocular biometry, a reappraisal of ciliary zonular functional anatomy, renewed investigation of the AC/A ratio, and the extent of a centripetal refractive influence on myopia development. © 2011 The College of Optometrists.

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Kernel-level malware is one of the most dangerous threats to the security of users on the Internet, so there is an urgent need for its detection. The most popular detection approach is misuse-based detection. However, it cannot catch up with today's advanced malware that increasingly apply polymorphism and obfuscation. In this thesis, we present our integrity-based detection for kernel-level malware, which does not rely on the specific features of malware. ^ We have developed an integrity analysis system that can derive and monitor integrity properties for commodity operating systems kernels. In our system, we focus on two classes of integrity properties: data invariants and integrity of Kernel Queue (KQ) requests. ^ We adopt static analysis for data invariant detection and overcome several technical challenges: field-sensitivity, array-sensitivity, and pointer analysis. We identify data invariants that are critical to system runtime integrity from Linux kernel 2.4.32 and Windows Research Kernel (WRK) with very low false positive rate and very low false negative rate. We then develop an Invariant Monitor to guard these data invariants against real-world malware. In our experiment, we are able to use Invariant Monitor to detect ten real-world Linux rootkits and nine real-world Windows malware and one synthetic Windows malware. ^ We leverage static and dynamic analysis of kernel and device drivers to learn the legitimate KQ requests. Based on the learned KQ requests, we build KQguard to protect KQs. At runtime, KQguard rejects all the unknown KQ requests that cannot be validated. We apply KQguard on WRK and Linux kernel, and extensive experimental evaluation shows that KQguard is efficient (up to 5.6% overhead) and effective (capable of achieving zero false positives against representative benign workloads after appropriate training and very low false negatives against 125 real-world malware and nine synthetic attacks). ^ In our system, Invariant Monitor and KQguard cooperate together to protect data invariants and KQs in the target kernel. By monitoring these integrity properties, we can detect malware by its violation of these integrity properties during execution.^

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In 2001, a weather and climate monitoring network was established along the temperature and aridity gradient between the sub-humid Moroccan High Atlas Mountains and the former end lake of the Middle Drâa in a pre-Saharan environment. The highest Automated Weather Stations (AWS) was installed just below the M'Goun summit at 3850 m, the lowest station Lac Iriki was at 450 m. This network of 13 AWS stations was funded and maintained by the German IMPETUS (BMBF Grant 01LW06001A, North Rhine-Westphalia Grant 313-21200200) project and since 2011 five stations were further maintained by the GERMAN DFG Fennec project (FI 786/3-1), this way some stations of the AWS network provided data for almost 12 years from 2001-2012. Standard meteorological variables such as temperature, humidity, and wind were measured at an altitude of 2 m above ground. Other meteorological variables comprise precipitation, station pressure, solar irradiance, soil temperature at different depths and for high mountain station snow water equivalent. The stations produced data summaries for 5-minute-precipitation-data, 10- or 15-minute-data and a daily summary of all other variables. This network is a unique resource of multi-year weather data in the remote semi-arid to arid mountain region of the Saharan flank of the Atlas Mountains. The network is described in Schulz et al. (2010) and its further continuation until 2012 is briefly discussed in Redl et al. (2015, doi:10.1175/MWR-D-15-0223.1) and Redl et al. (2016, doi:10.1002/2015JD024443).

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Kernel-level malware is one of the most dangerous threats to the security of users on the Internet, so there is an urgent need for its detection. The most popular detection approach is misuse-based detection. However, it cannot catch up with today's advanced malware that increasingly apply polymorphism and obfuscation. In this thesis, we present our integrity-based detection for kernel-level malware, which does not rely on the specific features of malware. We have developed an integrity analysis system that can derive and monitor integrity properties for commodity operating systems kernels. In our system, we focus on two classes of integrity properties: data invariants and integrity of Kernel Queue (KQ) requests. We adopt static analysis for data invariant detection and overcome several technical challenges: field-sensitivity, array-sensitivity, and pointer analysis. We identify data invariants that are critical to system runtime integrity from Linux kernel 2.4.32 and Windows Research Kernel (WRK) with very low false positive rate and very low false negative rate. We then develop an Invariant Monitor to guard these data invariants against real-world malware. In our experiment, we are able to use Invariant Monitor to detect ten real-world Linux rootkits and nine real-world Windows malware and one synthetic Windows malware. We leverage static and dynamic analysis of kernel and device drivers to learn the legitimate KQ requests. Based on the learned KQ requests, we build KQguard to protect KQs. At runtime, KQguard rejects all the unknown KQ requests that cannot be validated. We apply KQguard on WRK and Linux kernel, and extensive experimental evaluation shows that KQguard is efficient (up to 5.6% overhead) and effective (capable of achieving zero false positives against representative benign workloads after appropriate training and very low false negatives against 125 real-world malware and nine synthetic attacks). In our system, Invariant Monitor and KQguard cooperate together to protect data invariants and KQs in the target kernel. By monitoring these integrity properties, we can detect malware by its violation of these integrity properties during execution.

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Reduced surface-deep ocean exchange and enhanced nutrient consumption by phytoplankton in the Southern Ocean have been linked to lower glacial atmospheric CO2. However, identification of the biological and physical conditions involved and the related processes remains incomplete. Here we specify Southern Ocean surface-subsurface contrasts using a new tool, the combined oxygen and silicon isotope measurement of diatom and radiolarian opal, in combination with numerical simulations. Our data do not indicate a permanent glacial halocline related to melt water from icebergs. Corroborated by numerical simulations, we find that glacial surface stratification was variable and linked to seasonal sea-ice changes. During glacial spring-summer, the mixed layer was relatively shallow, while deeper mixing occurred during fall-winter, allowing for surface-ocean refueling with nutrients from the deep reservoir, which was potentially richer in nutrients than today. This generated specific carbon and opal export regimes turning the glacial seasonal sea-ice zone into a carbon sink.

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The ability to capture human motion allows researchers to evaluate an individual’s gait. Gait can be measured in different ways, from camera-based systems to Magnetic and Inertial Measurement Units (MIMU). The former uses cameras to track positional information of photo-reflective markers, while the latter uses accelerometers, gyroscopes, and magnetometers to measure segment orientation. Both systems can be used to measure joint kinematics, but the results vary because of their differences in anatomical calibrations. The objective of this thesis was to study potential solutions for reducing joint angle discrepancies between MIMU and camera-based systems. The first study worked to correct the anatomical frame differences between MIMU and camera-based systems via the joint angles of both systems. This study looked at full lower body correction versus correcting a single joint. Single joint correction showed slightly better alignment of both systems, but does not take into account that body segments are generally affected by more than one joint. The second study explores the possibility of anatomical landmarking using a single camera and a pointer apparatus. Results showed anatomical landmark position could be determined using a single camera, as the anatomical landmarks found from this study and a camera-based system showed similar results. This thesis worked on providing a novel way for obtaining anatomical landmarks with a single point-and-shoot camera, as well aligning anatomical frames between MIMUs and camera-based systems using joint angles.

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Las TIC son inseparables de la museografía in situ e imprescindibles en la museografía en red fija y móvil. En demasiados casos se han instalado prótesis tecnológicas para barnizar de modernidad el espacio cultural, olvidando que la tecnología debe estar al servicio de los contenidos de manera que resulte invisible y perfectamente imbricada con la museografía tradicional. Las interfaces móviles pueden fusionar museo in situ y en red y acompañar a las personas más allá del espacio físico. Esa fusión debe partir de una base de datos narrativa y abierta a obras materiales e inmateriales de otros museos de manera que no se trasladen las limitaciones del museo físico al virtual. En el museo in situ tienen sentido las instalaciones hipermedia inmersivas que faciliten experiencias culturales innovadoras. La interactividad (relaciones virtuales) debe convivir con la interacción (relaciones físicas y personales) y estar al servicio de todas las personas, partiendo de que todas, todos tenemos limitaciones. Trabajar interdisciplinarmente ayuda a comprender mejor el museo para ponerlo al servicio de las personas.

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Dissertação de Doutoramento em Estudos da Criança, apresentada ao Instituto de Estudos da Criança, Universidade do Minho,sob orientação da Professora Doutora Júlia Oliveira Formosinho. Disponível em http://hdl.handle.net/1822/7085

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La maladie de Hirschsprung est une affection congénitale de la motilité intestinale caractérisée par un segment aganglionnaire dans le côlon terminal. Un criblage génétique par mutation insertionnelle aléatoire chez la souris nous a permis d’identifier la lignée transgénique Spot dont les homozygotes souffrent de mégacôlon aganglionnaire. L’analyse d’intestins d’embryons mutants a révélé une baisse de prolifération et un délai de migration des cellules de la crête neurale entériques (CCNe) progénitrices dus à leur différenciation gliale précoce, entrainant un défaut de colonisation de l’intestin et une aganglionose du côlon. Le séquençage du génome Spot indique que le transgène s’est inséré à l’intérieur du locus K12-Nr2f1 sur le chromosome 13, une région dépourvue de gènes préalablement associés à la maladie, perturbant également une séquence non-codante très conservée dans l’évolution. K12 est un gène d’ARN long non codant (ARNlnc) et antisens du gène Nr2f1, lui-même impliqué dans la gliogénèse du système nerveux central. Le séquençage du transcriptome des CCN a montré une surexpression de Nr2f1 et des formes courtes de K12 chez Spot et des essais luciférase ont révélé l’activité répressive de l’élément conservé. Nous avons observé l’expression de K12 dans les CCNe et sa localisation subcellulaire dans des zones transcriptionnellement actives du noyau. Avec l’émergence des ARNlnc régulateurs, ces données nous permettent de pointer deux nouveaux gènes candidats associés à une différenciation gliale prématurée du SNE menant au mégacôlon aganglionnaire, en supposant que la régulation de Nr2f1 se fait par son antisens, K12.