1,498 research outputs found

    Ocular hypertension in myopia: analysis of contrast sensitivity

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    Purpose: we evaluated the evolution of contrast sensitivity reduction in patients affected by ocular hypertension and glaucoma, with low to moderate myopia. We also evaluated the relationship between contrast sensitivity and mean deviation of visual field. Material and methods: 158 patients (316 eyes), aged between 38 and 57 years old, were enrolled and divided into 4 groups: emmetropes, myopes, myopes with ocular hypertension (IOP≄21 ±2 mmHg), myopes with glaucoma. All patients underwent anamnestic and complete eye evaluation, tonometric curves with Goldmann’s applanation tonometer, cup/disc ratio evaluation, gonioscopy by Goldmann’s three-mirrors lens, automated perimetry (Humphrey 30-2 full-threshold test) and contrast sensitivity evaluation by Pelli-Robson charts. A contrast sensitivity under 1,8 Logarithm of the Minimum Angle of Resolution (LogMAR) was considered abnormal. Results: contrast sensitivity was reduced in the group of myopes with ocular hypertension (1,788 LogMAR) and in the group of myopes with glaucoma (1,743 LogMAR), while it was preserved in the group of myopes (2,069 LogMAR) and in the group of emmetropes (1,990 LogMAR). We also found a strong correlation between contrast sensitivity reduction and mean deviation of visual fields in myopes with glaucoma (coefficient relation = 0.86) and in myopes with ocular hypertension (coefficient relation = 0.78). Conclusions: the contrast sensitivity assessment performed by the Pelli-Robson test should be performed in all patients with middle-grade myopia, ocular hypertension and optic disc suspected for glaucoma, as it may be useful in the early diagnosis of the disease. Introduction Contrast can be defined as the ability of the eye to discriminate differences in luminance between the stimulus and the background. The sensitivity to contrast is represented by the inverse of the minimal contrast necessary to make an object visible; the lower the contrast the greater the sensitivity, and the other way around. Contrast sensitivity is a fundamental aspect of vision together with visual acuity: the latter defines the smallest spatial detail that the subject manages to discriminate under optimal conditions, but it only provides information about the size of the stimulus that the eye is capable to perceive; instead, the evaluation of contrast sensitivity provides information not obtainable with only the measurement of visual acuity, as it establishes the minimum difference in luminance that must be present between the stimulus and its background so that the retina is adequately stimulated to perceive the stimulus itself. The clinical methods of examining contrast sensitivity (lattices, luminance gradients, variable-contrast optotypic tables and lowcontrast optotypic tables) relate the two parameters on which the ability to distinctly perceive an object depends, namely the different luminance degree of the two adjacent areas and the spatial frequency, which is linked to the size of the object. The measurement of contrast sensitivity becomes valuable in the diagnosis and follow up of some important eye conditions such as glaucoma. Studies show that contrast sensitivity can be related to data obtained with the visual perimetry, especially with the perimetric damage of the central area and of the optic nerve head

    Replica Field Theory for Deterministic Models (II): A Non-Random Spin Glass with Glassy Behavior

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    We introduce and study a model which admits a complex landscape without containing quenched disorder. Continuing our previous investigation we introduce a disordered model which allows us to reconstruct all the main features of the original phase diagram, including a low TT spin glass phase and a complex dynamical behavior.Comment: 35 pages with uu figures, Roma 102

    Tecnologias para produção de citros na propriedade de base familiar.

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    Interleukin-35-Producing CD8α(+) Dendritic Cells Acquire a Tolerogenic State and Regulate T Cell Function.

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    Dendritic cells (DCs) play a central role in shaping immunogenic as well as tolerogenic adaptive immune responses and thereby dictate the outcome of adaptive immunity. Here, we report the generation of a CD8α(+) DC line constitutively secreting the tolerogenic cytokine interleukin (IL)-35. IL-35 secretion led to impaired CD4(+) and CD8(+) T lymphocyte proliferation and interfered with their function in vitro and also in vivo. IL-35 was furthermore found to induce a tolerogenic phenotype on CD8α(+) DCs, characterized by the upregulation of CD11b, downregulation of MHC class II, a reduced costimulatory potential as well as production of the immunomodulatory molecule IL-10. Vaccination of mice with IL-35-expressing DCs promoted tumor growth and reduced the severity of autoimmune encephalitis not only in a preventive but also after induction of encephalitogenic T cells. The reduction in experimental autoimmune encephalitis severity was significantly more pronounced when antigen-pulsed IL-35(+) DCs were used. These findings suggest a new, indirect effector mechanism by which IL-35-responding antigen-presenting cells contribute to immune tolerance. Furthermore, IL-35-transfected DCs may be a promising approach for immunotherapy in the context of autoimmune diseases

    Online Resource to Promote Vocational Interests Among Job Seekers With Multiple Sclerosis: A Randomized Controlled Trial in Australia

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    © 2017 American Congress of Rehabilitation Medicine Objective: To provide a preliminary evaluation of the effectiveness of an online resource for job seekers with multiple sclerosis (MS). Design: Randomized controlled design. Setting: Community-dwelling cohort. Participants: Adults (N = 95) with relapsing-remitting or progressive MS were randomly assigned to one of two groups. Forty-five accessed an email delivered, 7 module resource, Work and MS, over a 4 week period. Waitlist control participants (n=50) were offered the opportunity to access Work and MS 4 weeks postenrollment. Main Outcome Measures: Primary outcomes focused on vocational interests (My Vocational Situation Scale) and self-efficacy in job-seeking activities (Job-Procurement Self Efficacy Scale). Secondary outcomes focused on perceived workplace difficulties (Multiple Sclerosis Work Difficulties Questionnaire [MSWDQ]), optimism (Life Orientation Test – Revised), and mood (Patient Health Questionnaire-9). Results: Intention-to-treat analyses revealed pre-post gains: participants who accessed Work and MS reported improved confidence in their career goals (My Vocational Situation Scale g=.55; 95% confidence interval [CI],.14–.96; P=.008) and positively reappraised potential workplace difficulties (MSWDQ g range,.42–.47; P range,.023–.042). The effect on job self-efficacy was not significant, but changed in the expected direction (g=.17; 95% CI, –.23 to.57; P=.409). Completer data revealed larger, significant effect estimates (g range,.52–.64; P range,.009–.035). Conclusions: Findings provide preliminary support for the utility of a job information resource, Work and MS, to augment existing employment services. The results also suggest the need to test employment-ready interventions in a larger study population. This might include the addition of online peer support to increase intervention compliance

    Finite-Connectivity Spin-Glass Phase Diagrams and Low Density Parity Check Codes

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    We obtain phase diagrams of regular and irregular finite connectivity spin-glasses. Contact is firstly established between properties of the phase diagram and the performances of low density parity check codes (LDPC) within the Replica Symmetric (RS) ansatz. We then study the location of the dynamical and critical transition of these systems within the one step Replica Symmetry Breaking theory (RSB), extending similar calculations that have been performed in the past for the Bethe spin-glass problem. We observe that, away from the Nishimori line, in the low temperature region, the location of the dynamical transition line does change within the RSB theory, in comparison with the (RS) case. For LDPC decoding over the binary erasure channel we find, at zero temperature and rate R=1/4 an RS critical transition point located at p_c = 0.67 while the critical RSB transition point is located at p_c = 0.7450, to be compared with the corresponding Shannon bound 1-R. For the binary symmetric channel (BSC) we show that the low temperature reentrant behavior of the dynamical transition line, observed within the RS ansatz, changes within the RSB theory; the location of the dynamical transition point occurring at higher values of the channel noise. Possible practical implications to improve the performances of the state-of-the-art error correcting codes are discussed.Comment: 21 pages, 15 figure
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