906 resultados para coherence rivalry


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Background: Malignant hypertension is defined by marked systemic arterial hypertension with retinal haemorrhages, exudation or papilloedema. Due to the rarity of this disease and due to its non-specific symptoms and lesions, the diagnosis can be challenging. Patients and Methods We investigated the types of symptoms and ocular lesions observed with ocular fundus examination, ocular fundus photography, fluorescein angiography and optical coherence tomography in a small case series of 7 patients with malignant hypertension. Results: Median systolic blood pressure (BP) was 205 mmHg ± 21. Median diastolic BP was 150 mmHg ± 16. Decrease in visual acuity (6/7 patients) and scotoma (5/7) were the main symptoms and Elschnig spot, flamed shaped haemorrhage, serous retinal detachment, cotton wool spots and optic nerve oedema were the five most frequently observed lesions. A regression of lesions was observed after therapy of systemic hypertension. Conclusion: The association of multiple lesions strongly suggests malignant hypertension. However even in cases with only one lesion malignant hypertension should be kept in mind.

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We propose a novel formulation to solve the problem of intra-voxel reconstruction of the fibre orientation distribution function (FOD) in each voxel of the white matter of the brain from diffusion MRI data. The majority of the state-of-the-art methods in the field perform the reconstruction on a voxel-by-voxel level, promoting sparsity of the orientation distribution. Recent methods have proposed a global denoising of the diffusion data using spatial information prior to reconstruction, while others promote spatial regularisation through an additional empirical prior on the diffusion image at each q-space point. Our approach reconciles voxelwise sparsity and spatial regularisation and defines a spatially structured FOD sparsity prior, where the structure originates from the spatial coherence of the fibre orientation between neighbour voxels. The method is shown, through both simulated and real data, to enable accurate FOD reconstruction from a much lower number of q-space samples than the state of the art, typically 15 samples, even for quite adverse noise conditions.

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Mast cells are important in the initiation of ocular inflammation, but the consequences of mast cell degranulation on ocular pathology remain uncharacterized. We induced mast cell degranulation by local subconjunctival injection of compound 48/80. Initial degranulation of mast cells was observed in the choroid 15 minutes after the injection and increased up to 3 hours after injection. Clinical signs of anterior segment inflammation paralleled mast cell degranulation. With the use of optical coherence tomography, dilation of choroidal vessels and serous retinal detachments (SRDs) were observed and confirmed by histology. Subconjunctival injection of disodium cromoglycate significantly reduced the rate of SRDs, demonstrating the involvement of mast cell degranulation in posterior segment disorders. The infiltration of polymorphonuclear and macrophage cells was associated with increased ocular media concentrations of tumor necrosis factor-α, CXCL1, IL-6, IL-5, chemokine ligand 2, and IL-1β. Analysis of the amounts of vascular endothelial growth factor and IL-18 showed an opposite evolution of vascular endothelial growth factor compared with IL-18 concentrations, suggesting that they regulate each other's production. These findings suggest that the local degranulation of ocular mast cells provoked acute ocular inflammation, dilation, increased vascular permeability of choroidal vessels, and SRDs. The involvement of mast cells in retinal diseases should be further investigated. The pharmacologic inhibition of mast cell degranulation may be a potential target for intervention.

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Using mean field theory, we have studied Bose-Fermi mixtures in a one-dimensional optical lattice in the case of an attractive boson-fermion interaction. We consider that the fermions are in the degenerate regime and that the laser intensities are such that quantum coherence across the condensate is ensured. We discuss the effect of the optical lattice on the critical rotational frequency for vortex line creation in the Bose-Einstein condensate, as well as how it affects the stability of the boson-fermion mixture. A reduction of the critical frequency for nucleating a vortex is observed as the strength of the applied laser is increased. The onset of instability of the mixture occurs for a sizably lower number of fermions in the presence of a deep optical lattice.

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The aims of this study were 1) to clarify the factors associated with family functioning in cancer patient’s families with dependant children, 2) to examine children’ mental health when they are exposed to parental cancer, 3) to explore the subjective experience of having cancer during pregnancy, and finally, 4) to describe the implementation of a childcentred family intervention for cancer patients’ families with dependant children in an adult oncology setting. The study groups were collected between May 1st 2002 and April 30th 2004. They consisted of one European group collected from six different countries (N = 381) and two Finnish clinical groups (N = 85 and N = 2). The first Finnish clinical group of 85 cancer patient families with dependant children included a sub-sample of 54 families with children aged 11-17 years. The second Finnish clinical group consisted of two pregnant cancer patients. Additionally, a control group (N = 59) consisting of a sub-sample of 49 families with children aged 11-17 years was used. Quantitative methods (FAD, BDI, YSR, SOC, SF-8) and qualitative methods (observation, interviews, diaries, videotapes) were used exclusively and/or in combination. The results can be summarised as follows: 1) cancer “per se “ did not impair family functioning, children’s mental health, early interaction between ill mothers and their infant, 2) maternal depression or the ill parent’s depression were significantly associated with impairment in family functioning, 3) the individual’s good sense of coherence was associated with improvement in family functioning, and 4) a child-centred family intervention, which aims to give space for elaborating on cancer in the family, validates the sense of coherence and children’s feelings, and promotes open communication was welcomed. It is important to note that in the European study group, the prevalence of depression was 35 % (BDI > 16) among ill mothers, and 28% among healthy mothers, 28% among ill fathers, and 13% among healthy fathers. Early screening and effective treatment of depression in cancer patients and their partners is of paramount importance for the mental health of children and the well-being of the family. Pregnant cancer patients are in need of psychosocial support.

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Previous studies have identified the rivalry among technological platforms as one of the main driving forces of broadband services penetration. This paper draws on data from the Spanish market between 2005 and 2011 to estimate the main determinants of broadband prices. Controlling for broadband tariffs features and network variables, we examine the impact of the different modes of competition on prices. We find that inter-platform competition has no significant effects over prices, while intra-platform competition is a key driver of the prices charged in the broadband market. Our analysis suggests that the impact of different types of competition on prices is critically affected by the levels of development of the broadband market achieved by the considered country

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PurposeTo evaluate the impact of traditional French summer vacation on visual acuity and spectral domain-optical coherence tomography (SD-OCT) of Wet AMD patients being treated with intravitreal Ranibizumab.MethodsThis was a consecutive, comparative, single-centre, prospective analysis. All patients who were being treated with intravitreal injection of 0.5 mg ranibizumab at Cergy Pontoise Hospital, Department of Ophthalmology between July 2013 and September 2014 were included. Patients were divided into two groups: (A) patients who skipped one ranibizumab intravitreal injection during holidays, and (B) patients who received injection during their holidays. Evaluations occurred prior to traditional holiday (baseline) and 2 months later, consisting of BCVA using ETDRS, and a complete ophthalmic examination that included slit-lamp biomicroscopy, fundus examination, fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral domain-optical coherence tomography (SD-OCT). All patients were being treated with PRN anti-VEGF regimen and criteria for reinjection included a visual acuity loss >5 ETDRS letters and/or an increase of central retinal thickness, presence of subretinal fluid, intraretinal fluid, or pigment epithelium detachment. If reinjection criteria were not met, patients were advised to return in 4 weeks.ResultsThe mean visual acuity change was -0.071±0.149 (LogMAR) in group A and +0.003±0.178 in group B (P=0.041). At the second visit (2 months after preholidays visit), 61.8% of patients in group A had SRF and/or intraretinal cysts, and only 27.6% of patients in group B. There was a significant difference in the persistence of fluid between the two groups (P=0.007, χ(2)-test).ConclusionThis cases series demonstrated the detrimental impact of holidays on visual acuity in patients treated with ranibizumab for AMD, which, in spite of their treatment regimen, still leave in vacation. Therefore, it is important to convey the message of treatment adherence to patients, despite their need of holidays.

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A long-standing question in biology and economics is whether individual organisms evolve to behave as if they were striving to maximize some goal function. We here formalize this "as if" question in a patch-structured population in which individuals obtain material payoffs from (perhaps very complex multimove) social interactions. These material payoffs determine personal fitness and, ultimately, invasion fitness. We ask whether individuals in uninvadable population states will appear to be maximizing conventional goal functions (with population-structure coefficients exogenous to the individual's behavior), when what is really being maximized is invasion fitness at the genetic level. We reach two broad conclusions. First, no simple and general individual-centered goal function emerges from the analysis. This stems from the fact that invasion fitness is a gene-centered multigenerational measure of evolutionary success. Second, when selection is weak, all multigenerational effects of selection can be summarized in a neutral type-distribution quantifying identity-by-descent between individuals within patches. Individuals then behave as if they were striving to maximize a weighted sum of material payoffs (own and others). At an uninvadable state it is as if individuals would freely choose their actions and play a Nash equilibrium of a game with a goal function that combines self-interest (own material payoff), group interest (group material payoff if everyone does the same), and local rivalry (material payoff differences).

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Abstract This work studies the multi-label classification of turns in simple English Wikipedia talk pages into dialog acts. The treated dataset was created and multi-labeled by (Ferschke et al., 2012). The first part analyses dependences between labels, in order to examine the annotation coherence and to determine a classification method. Then, a multi-label classification is computed, after transforming the problem into binary relevance. Regarding features, whereas (Ferschke et al., 2012) use features such as uni-, bi-, and trigrams, time distance between turns or the indentation level of the turn, other features are considered here: lemmas, part-of-speech tags and the meaning of verbs (according to WordNet). The dataset authors applied approaches such as Naive Bayes or Support Vector Machines. The present paper proposes, as an alternative, to use Schoenberg transformations which, following the example of kernel methods, transform original Euclidean distances into other Euclidean distances, in a space of high dimensionality. Résumé Ce travail étudie la classification supervisée multi-étiquette en actes de dialogue des tours de parole des contributeurs aux pages de discussion de Simple English Wikipedia (Wikipédia en anglais simple). Le jeu de données considéré a été créé et multi-étiqueté par (Ferschke et al., 2012). Une première partie analyse les relations entre les étiquettes pour examiner la cohérence des annotations et pour déterminer une méthode de classification. Ensuite, une classification supervisée multi-étiquette est effectuée, après recodage binaire des étiquettes. Concernant les variables, alors que (Ferschke et al., 2012) utilisent des caractéristiques telles que les uni-, bi- et trigrammes, le temps entre les tours de parole ou l'indentation d'un tour de parole, d'autres descripteurs sont considérés ici : les lemmes, les catégories morphosyntaxiques et le sens des verbes (selon WordNet). Les auteurs du jeu de données ont employé des approches telles que le Naive Bayes ou les Séparateurs à Vastes Marges (SVM) pour la classification. Cet article propose, de façon alternative, d'utiliser et d'étendre l'analyse discriminante linéaire aux transformations de Schoenberg qui, à l'instar des méthodes à noyau, transforment les distances euclidiennes originales en d'autres distances euclidiennes, dans un espace de haute dimensionnalité.

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PURPOSE: To investigate the incidence of outer retinal tubulation (ORT) in ranibizumab-treated neovascular age-related macular degeneration patients. METHODS: We included 480 consecutive patients (546 eyes) with neovascular age-related macular degeneration, who were treated with variable-dosing intravitreal ranibizumab, evaluated with spectral domain optical coherence tomography, and followed-up for a minimum period of 6 months. Optical coherence tomographies were evaluated for the first appearance of ORT, precursor signs, and type of underlying lesion. Visual acuity was also recorded. RESULTS: Outer retinal tubulation was observed in 30% of eyes during a mean follow-up period of 26.7 months (SD, 13.5). Kaplan-Meier survival analysis revealed that the ORT incidence (2.5, 17.5, 28.4, and 41.6% at baseline, after 1, 2, and 4 years, respectively) continuously increased, despite visually effective anti-vascular endothelial growth factor treatment. Outer retinal tubulation was associated with a poorer functional benefit. Lower baseline visual acuity was associated with a higher risk of developing ORT. CONCLUSION: Incidence of ORT continuously increases despite visually optimal anti-vascular endothelial growth factor treatment of age-related macular degeneration. Outer retinal tubulation might be considered a prognostic factor for functional outcome and is relevant to avoid overtreatment.

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Biocompatibility is a requirement for the development of nanofibers for ophthalmic applications. In this study, nanofibers were elaborated using poly(ε-caprolactone) via electrospinning. The ocular biocompatibility of this material was investigated. MIO-M1 and ARPE-19 cell cultures were incubated with nanofibers and cellular responses were monitored by viability and morphology. The in vitro biocompatibility revealed that the nanofibers were not cytotoxic to the ocular cells. These cells exposed to the nanofibers proliferated and formed an organized monolayer. ARPE-19 and MIO-M1 cells were capable of expressing GFAP, respectively, demonstrating their functionality. Nanofibers were inserted into the vitreous cavity of the rat's eye for 10days and the in vivo biocompatibility was investigated using Optical Coherence Tomography (OCT), histology and measuring the expression of pro-inflammatory genes (IL-1β, TNF-α, VEGF and iNOS) (real-time PCR). The OCT and the histological analyzes exhibited the preserved architecture of the tissues of the eye. The biomaterial did not elicit an inflammatory reaction and pro-inflammatory cytokines were not expressed by the retinal cells, and the other posterior tissues of the eye. Results from the biocompatibility studies indicated that the nanofibers exhibited a high degree of cellular biocompatibility and short-term intraocular tolerance, indicating that they might be applied as drug carrier for ophthalmic use.

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PURPOSE: To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report 6 novel mutations, to characterize the biochemical features of a recurrent novel mutation, and to study the clinical features of adRP patients. DESIGN: Retrospective clinical and molecular genetic study. METHODS: Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging, and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot. RESULTS: We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1-0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families. CONCLUSIONS: The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0%-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases, which could be underdiagnosed.

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We consider the problem of multiple correlated sparse signals reconstruction and propose a new implementation of structured sparsity through a reweighting scheme. We present a particular application for diffusion Magnetic Resonance Imaging data and show how this procedure can be used for fibre orientation reconstruction in the white matter of the brain. In that framework, our structured sparsity prior can be used to exploit the fundamental coherence between fibre directions in neighbour voxels. Our method approaches the ℓ0 minimisation through a reweighted ℓ1-minimisation scheme. The weights are here defined in such a way to promote correlated sparsity between neighbour signals.

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This volume deals with the forms of propaganda and self-representation, through words and images, during the rise of the 'civiltà delle corti' and through processes typical of the time, such as confrontation, adaptation, competition and rivalry. This period, which marked the passage of Italian and European culture from the Middle Ages to the Renaissance, is fundamental in the development of Modern Europe, and it lasted up to the XVIII century and beyond. At the heart of many matters debated here lies the relationship between culture and politics. The formation of a 'Lombard identity', central to the Sinergia project which was the frame of the whole research and its conferences, is closely linked to this broad general context. It places the so called 'questione milanese' - above the traditional hierarchies 'Toscana oriented' - at the centre of many questions regarding Northern Italy as a whole, starting from the dissolution of the Medieval communes, through to the rise of the signorie, from the end of the XIII century and the beginning of the XIV century up to the early XVI century.

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Le self est une notion polysémique qui fait l'objet d'un consensus relatif dans plusieurs domaines, dont la psychologie du développement. Elle rend compte de la faculté de s'éprouver le même au fil du temps et de distinguer le « je » qui regarde du « moi » regardé. C'est le garant d'un sens de soi plus ou moins cohérent au fil du temps, en dépit des changements qui surviennent au cours de la vie. Le self combine des processus de réflexivité et d'intersubjectivité. Nous en avons analysé trois composantes fonctionnelles : la mémoire de travail, la mémoire épisodique et la narration, à partir d'un protocole expérimental témoignant de son ontogenèse chez des enfants de 6 à 9 ans (n=24 répartis en deux groupes de 6‐7 et 8-9 ans). Nous avons créé le « jeu informatique du lutin » qui propose un parcours semiorienté dans un monde imaginaire. C'est une narration de soi, opérant la mise en sens des temporalités et des espaces auxquels les événements se réfèrent. Deux semaines après cette « aventure », on recueille la narration des souvenirs épisodiques de cette histoire. Nous avons également utilisé un test de mémoire de travail visuospatiale non verbale. Des différences développementales affectent les dimensions narratives de la mémoire de l'épisode du jeu, comme l'efficacité de la mémoire de travail visuospatiale. Ces développements témoignent d'une augmentation de « l'épaisseur temporelle de la conscience» entre 6 et 9 ans. L'épaisseur de la conscience renvoie fondamentalement à la faculté du self de vivre le temps dans une cyclicité incluant le passé, le présent et le futur anticipé. Le développment observé élargit les possibilités de mettre en lien des mémoires et des scénarios futurs, tout comme les mises en sens des relations aux autres et à soi-­même. Self is a polysemic concept of common use in various scientific fields, among which developmental psychology. It accounts for the capacity to maintain the conviction to be « oneself », always the same through circumstances and throughout my life. This important function contributes in maintaining coherence and some sorte of Ariadne's thread in memory. To analyse the ontogeny of the self, we have focused upon three components : working memory, episodic memory and narration in children aged between 6 and 9 years. We used a non verbal working memory task. It was completed by a video game specially designed for our purpose, in which children were engaged in moving an elf in a landscape changing through seasons, in order to deliver a princess from a mischievous wizard. Two weeks after the game, the children had to tell what happened while they moved the elf. It is a self-narrative that creates a link‐up of temporality and spaces to which the events refer. The narrated episode was assessed for its coherence and continuity dimensions. Developmental differences affect the narrative dimensions of the memory of the episode of the game, as the effectiveness of visuospatial working memory. These developments show an increase in "temporal thickness of consciousness" between 6 and 9 years. The thickness of consciousness basically refers to the ability of the self to live in a cyclical time including past, present and anticipated future. The observed development broadens the possibilities to link memories and future scenarios, like setting sense of relations with others and with oneself.