236 research outputs found

    Yokoyama procedure efficacy on non-highly myopic patients with acquired esotropia and hypotropia

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    Objective: To assess the efficacy of \u201cYokoyama Procedure,\u201d on non-highly myopic patients with acquired esotropia and hypotropia. Methods: The study involved 10 eyes of 5 patients with eso-hypotropia. Inclusion criteria were acquired esotropic-hypotropic strabismus with lateral rectus inferior displacement and superior rectus nasal displacement confirmed by magnetic resonance imaging, refractive errors between \ub16 D, and axial length < 27 mm. Range of full duction movements and maximum angles of abduction-sursumduction was measured in each eye before and after surgery. All patients underwent T1- and T2-weighted magnetic resonance imaging. The surgery was aimed at creating a junction between the muscle bellies of the superior and lateral rectus muscles. This junction was made approximately 14 mm behind the insertions using a non-absorbable mersilene 5/0 suture (Yokoyama procedure). Results: Mean patient age was 64.8 \ub1 4.8 years. The mean globe axial length was 25.4 \ub1 0.76 mm and a mean corresponding spherical equivalent refraction of 123.7 \ub1 1.7 D was observed. Eight eyes on 10 had mild limitation in abduction, while the remaining 2 had no limitation. Three out of 10 eyes showed a moderate limited sursumduction, 5 eyes were categorized as mild, and the remaining 2 had no limitation. No evident post-operative limitation was present in any eye, in both abduction and sursumduction (p < 0.01). Pre-operative esotropia and hypotropia were, respectively, 32 \ub1 11 prismatic diopters and 25 \ub1 5 prismatic diopters, and they were significantly reduced after surgery as 9 \ub1 1.7 prismatic diopters and 6 \ub11 prismatic diopters (p = 0.043), respectively. Conclusion: Yokoyama procedure is an effective, fast, reversible procedure to face eso-hypotropic acquired strabismus, even in patients with a clear magnetic resonance imaging displacement of superior and lateral rectus muscles, and absence of globe dislocation and of elevated myopia

    Decade-long profile of imaging biomarker use in ophthalmic clinical trials

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    PURPOSE. The purpose of this study was to investigate the use of imaging biomarkers in published clinical trials (CTs) in ophthalmology and its eventual changes during the past 10 years. METHODS. We sampled from published CTs in the fields of cornea, retina, and glaucoma between 2005\u20132006 and 2015\u20132016. Data collected included year of publication, phase, subspecialty, location, compliance with Consolidated Standards for Reporting Trials, impact factor, presence and use of imaging biomarkers (diagnostic, prognostic and predictive; primary and secondary surrogate endpoints), and use of centralized reading centers. RESULTS. We included 652 articles for analysis, equally distributed in three timeframes (2005\u2013 2006, 2010\u20132011, and 2015\u20132016), mainly reporting phase IV CTs and trials on procedures (42.2% and 35.4%, respectively). Imaging biomarkers were included in 46.3% of the analyzed CTs and their use significantly increased over time (P < 0.05). Optical coherence tomography was the most frequently used device (27.7%), whereas diagnostic biomarkers and secondary surrogate endpoints were the most frequent biomarker types (19.5% and 22.5%, respectively). Early-phase CTs showed an increase in the use of biomarkers for patient selection and stratification over time (P < 0.05), but not in the use of imaging surrogate endpoints (P = 0.90). Only 3 of 59 (5.1%) of phase III CTs included primary surrogate imaging endpoints, whereas secondary surrogate imaging endpoints were present in 50.8% of these trials (P < 0.001). Retinal CTs had the highest prevalence for each type of imaging biomarker (P < 0.001). Reading centers were used in 52 of 302 CTs (17.2%), with no significant time-related increase. CONCLUSIONS. Imaging biomarkers are increasingly used in published CTs in ophthalmology. Additional efforts, including centralized reading centers, are needed to improve their validation and use, allowing a wider use of these tools as primary surrogate endpoints in phase III CTs

    Experimental evidence of adiabatic splitting of charged particle beams using stable islands of transverse phase space

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    Recently, a novel technique to perform multi-turn extraction from a circular particle accelerator was proposed. It is based on beam splitting and trapping, induced by a slow crossing of a nonlinear resonance, inside stable islands of transverse phase space. Experiments at the CERN Proton Synchrotron started in 2002 and evidence of beam splitting was obtained by summer 2004. In this paper the measurement results achieved with both a low- and a high-intensity, single-bunch proton beam are presented

    Foregrounds in the BOOMERANG-LDB data: a preliminary rms analysis

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    We present a preliminary analysis of the BOOMERanG LDB maps, focused on foregrounds. BOOMERanG detects dust emission at moderately low galactic latitudes (b>20ob > -20^o) in bands centered at 90, 150, 240, 410 GHz. At higher Galactic latitudes, we use the BOOMERanG data to set conservative upper limits on the level of contamination at 90 and 150 GHz. We find that the mean square signal correlated with the IRAS/DIRBE dust template is less than 3% of the mean square signal due to CMB anisotropy

    Darts fast-learning reduces theta power but is not affected by Hf-tRNS: A behavioral and electrophysiological investigation

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    Sports trainers have recently shown increasing interest in innovative methods, including transcranial electric stimulation, to enhance motor performance and boost the acquisition of new skills during training. However, studies on the effectiveness of these tools on fast visuomotor learning and brain activity are still limited. In this randomized single-blind, sham-controlled, between-subjects study, we investigated whether a single training session, either coupled or not with 2 mA online high-frequency transcranial random noise stimulation (hf-tRNS) over the bilateral primary motor cortex (M1), would affect dart-throwing performance (i.e., radial error, arm range of motion, and movement variability) in 37 healthy volunteers. In addition, potential neurophysiological correlates were monitored before and after the training through a 32-electrode portable electroencephalogram (EEG). Results revealed that a single training session improved radial error and arm range of motion during the dart-throwing task, but not movement variability. Furthermore, after the training, resting state-EEG data showed a decrease in theta power. Radial error, arm movement, and EEG were not further modulated by hf-tRNS. This indicates that a single training session, regardless of hf-tRNS administration, improves dart-throwing precision and movement accuracy. However, it does not improve movement variability, which might require multiple training sessions (expertise resulting in slow learning). Theta power decrease could describe a more efficient use of cognitive resources (i.e., attention and visuomotor skills) due to the fast dart-throwing learning. Further research could explore different sports by applying longer stimulation protocols and evaluating other EEG variables to enhance our understanding of the lasting impacts of multi-session hf-tRNS on the sensorimotor cortex within the framework of slow learning and training assistance

    Mapping the CMB Sky: The BOOMERANG experiment

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    We describe the BOOMERanG experiment, a stratospheric balloon telescope intended to measure the Cosmic Microwave Background anisotropy at angular scales between a few degrees and ten arcminutes. The experiment has been optimized for a long duration (7 to 14 days) flight circumnavigating Antarctica at the end of 1998. A test flight was performed on Aug.30, 1997 in Texas. The level of performance achieved in the test flight was satisfactory and compatible with the requirements for the long duration flight.Comment: 11 pages, 6 figure

    Loss of renal function in the elderly italians: a physiologic or pathologic process?

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    Abstract BACKGROUND: Nowadays it seems that chronic kidney disease (CKD) is outbreaking, mostly in the elderly participants. The aim of this study was to assess the progression of CKD in different ages. METHODS: We conducted a monocentric, retrospective, observational study enrolling 116 patients afferent to our outpatient clinic. INCLUSION CRITERIA: age >18 years, follow-up ≥5 years, estimated glomerular filtration rate (eGFR) <60mL/min/1.73 m(2), and/or diagnosed renal disease and/or presence of renal damage. Patients were divided into four groups according to their age: 25-55 years (n = 27), 56-65 (25), 66-75 (42), and 76-87 (22). eGFR was calculated using the modification of diet in renal disease and the CKD-epidemiology collaboration formulas. RESULTS: Younger patients had a significantly longer follow-up and less comorbidities, evaluated by the cumulative illness rating scale score, compared with the other groups. There was no difference between creatinine at baseline and at the end-of-follow-up period among the groups. Even though renal function significantly decreased in all groups, we noticed a slower progression as the age increased, and the difference between basal and end-of-follow-up eGFR was minimal in the group of patients aged 76-87 years. Analyzing the eGFR of every ambulatory control plotted against the year of follow-up, we showed a more rapid loss of filtrate in the younger group. Instead, loss of renal function decreased as the age of patients increased. CONCLUSIONS: This study demonstrates that, in elderly Italian participants, progression of CKD occurs more slowly than in younger patients. This implies that we may probably face an epidemic of CKD but that most of elderly patients diagnosed with CKD may not evolve to end-stage renal disease and require renal replacement therapy

    First Estimations of Cosmological Parameters From BOOMERANG

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    The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first Antarctic flight of the BOOMERANG experiment. Within the framework of inflation-motivated adiabatic cold dark matter models, and using only weakly restrictive prior probabilites on the age of the universe and the Hubble expansion parameter hh, we find that the curvature is consistent with flat and that the primordial fluctuation spectrum is consistent with scale invariant, in agreement with the basic inflation paradigm. We find that the data prefer a baryon density Ωbh2\Omega_b h^2 above, though similar to, the estimates from light element abundances and big bang nucleosynthesis. When combined with large scale structure observations, the BOOMERANG data provide clear detections of both dark matter and dark energy contributions to the total energy density Ωtot\Omega_{\rm {tot}}, independent of data from high redshift supernovae.Comment: As submitted to PRD, revised longer version with an additional figur

    Noise Properties of the BOOMERANG Instrument

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    In this paper we report a short description of the BOOMERANG experiment explaining his scientific goal and the technologies implied. We concentrate then on the analysis of the noise properties discussing in particular the scan synchronous noise. Finally we present the calibration technique and the sensitivity of all the channels

    The BOOMERANG North America Instrument: a balloon-borne bolometric radiometer optimized for measurements of cosmic background radiation anisotropies from 0.3 to 4 degrees

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    We describe the BOOMERANG North America (BNA) instrument, a balloon-borne bolometric radiometer designed to map the Cosmic Microwave Background (CMB) radiation with 0.3 deg resolution over a significant portion of the sky. This receiver employs new technologies in bolometers, readout electronics, millimeter-wave optics and filters, cryogenics, scan and attitude reconstruction. All these subsystems are described in detail in this paper. The system has been fully calibrated in flight using a variety of techniques which are described and compared. It has been able to obtain a measurement of the first peak in the CMB angular power spectrum in a single balloon flight, few hours long, and was a prototype of the BOOMERANG Long Duration Balloon (BLDB) experiment.Comment: 40 pages, 22 figures, submitted to Ap
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