Individuals with cerebral visual impairment (CVI) have difficulties identifying common objects, especially when presented as cartoons or abstract images. In this study, participants were shown a ...series of images of ten common objects, each from five possible categories ranging from abstract black & white line drawings to color photographs. Fifty individuals with CVI and 50 neurotypical controls verbally identified each object and success rates and reaction times were collected. Visual gaze behavior was recorded using an eye tracker to quantify the extent of visual search area explored and number of fixations. A receiver operating characteristic (ROC) analysis was also carried out to compare the degree of alignment between the distribution of individual eye gaze patterns and image saliency features computed by the graph-based visual saliency (GBVS) model. Compared to controls, CVI participants showed significantly lower success rates and longer reaction times when identifying objects. In the CVI group, success rate improved moving from abstract black & white images to color photographs, suggesting that object form (as defined by outlines and contours) and color are important cues for correct identification. Eye tracking data revealed that the CVI group showed significantly greater visual search areas and number of fixations per image, and the distribution of eye gaze patterns in the CVI group was less aligned with the high saliency features of the image compared to controls. These results have important implications in helping to understand the complex profile of visual perceptual difficulties associated with CVI.
Fabry–Perot cavities have many different applications as scientific instruments. In the gravitational waves research field they are extensively used to frequency stabilize lasers and to measure very ...small distance variations. In the present Letter a method to evaluate from the transmitted power only the relative speed and position of the mirrors of a cavity, having finesse
F>40
, is described. A displacement spectral sensitivity of the order of about 3×10
−10 m/Hz
−1/2 at 10 Hz is obtained with the cavity of the low frequency facility.
Summary Background Aicardi-Goutières syndrome (AGS) is an inflammatory disorder caused by mutations in any of six genes ( TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1 , and ADAR ). The disease is ...severe and effective treatments are urgently needed. We investigated the status of interferon-related biomarkers in patients with AGS with a view to future use in diagnosis and clinical trials. Methods In this case-control study, samples were collected prospectively from patients with mutation-proven AGS. The expression of six interferon-stimulated genes (ISGs) was measured by quantitative PCR, and the median fold change, when compared with the median of healthy controls, was used to create an interferon score for each patient. Scores higher than the mean of controls plus two SD (>2·466) were designated as positive. Additionally, we collated historical data for interferon activity, measured with a viral cytopathic assay, in CSF and serum from mutation-positive patients with AGS. We also undertook neutralisation assays of interferon activity in serum, and looked for the presence of autoantibodies against a panel of interferon proteins. Findings 74 (90%) of 82 patients had a positive interferon score (median 12·90, IQR 6·14–20·41) compared with two (7%) of 29 controls (median 0·93, IQR 0·57–1·30). Of the eight patients with a negative interferon score, seven had mutations in RNASEH2B (seven 27% of all 26 patients with mutations in this gene). Repeat sampling in 16 patients was consistent for the presence or absence of an interferon signature on 39 of 41 occasions. Interferon activity (tested in 147 patients) was negatively correlated with age (CSF, r =−0·604; serum, r =−0·289), and was higher in CSF than in serum in 104 of 136 paired samples. Neutralisation assays suggested that measurable antiviral activity was related to interferon α production. We did not record significantly increased concentrations of autoantibodies to interferon subtypes in patients with AGS, or an association between the presence of autoantibodies and interferon score or serum interferon activity. Interpretation AGS is consistently associated with an interferon signature, which is apparently sustained over time and can thus be used to differentiate patients with AGS from controls. If future studies show that interferon status is a reactive biomarker, the measurement of an interferon score might prove useful in the assessment of treatment efficacy in clinical trials. Funding European Union's Seventh Framework Programme; European Research Council.
The low frequency facility, a Virgo R&D experiment, is composed by a Fabry–Perot cavity attached and controlled by the Virgo suspension; the goal is to measure the thermal noise of the apparatus ...above 10 Hz, with a displacement sensitivity as high as 10
−18 m
/
Hz
. Since September 2001 the apparatus, located inside the INFN-Pisa experimental area, has been completely built and put into operation. Vacuum facilities and the control loops have been set up. Transfer functions, necessary to control the cavity, absolute test mass displacement and the first demonstration of the cavity locking are reported.
This manuscript reviews all patients who underwent orthotopic heart transplantations (OHT) at our program (116 patients underwent 119 OHT) to describe their diagnostic characteristics and to assess ...risk factors for mortality.
Median age at OHT was 179 days (mean, 1,446.6 ± 188.9 days 4.0 ± 0.5 years; range, 5 days to 7,125 days 19.5 years; 15 neonates, 68 infants). Median weight at OHT was 5.5 kg (mean, 17.2 ± 2.1 kg; range, 2.2 to 113 kg). Diagnoses were cardiomyopathy (n = 37), primary transplantation for hypoplastic left heart syndrome (HLHS) or HLHS-related malformation (n = 29), transplantation after prior cardiac surgery for HLHS or HLHS-related malformation (n = 9), non-HLHS congenital heart disease (n = 39), and retransplant (n = 5).
Overall Kaplan-Meier 5-year survival was 72.7%. Operative mortality was 12.6% (15 patients). Late mortality was 13.4% (16 patients). Eighty-five patients survived, with a mean follow-up of 5.76 ± 0.48 years (median, 5.1 years; range, 0.12 to 14.0 years). Total follow-up was 507.0 years. No survival difference was seen among the five diagnostic subgroups (p = 0.20). Univariate association between risk factors and survival was assessed for the following variables: age (p = 0.91), weight (p = 0.86), sex (p = 0.47), race (p = 0.40), insurance classification (p = 0.42), high PRA (p = 0.20), pretransplant mechanical circulatory support (p < 0.001), posttransplant mechanical circulatory support (p < 0.001), redo sternotomy (p = 0.07), heterotaxy (p = 0.02), cardiopulmonary bypass time (p = 0.01), and donor heart cross-clamp time (p = 0.02).
Excellent results are expected for children undergoing OHT regardless of diagnostic classification. Pretransplant mechanical circulatory support, posttransplant mechanical circulatory support, cardiopulmonary bypass time, donor heart cross-clamp time, and heterotaxy are risk factors for decreased survival.
Different pathologic processes (especially demyelination, hypomyelination, and combinations of these) may underlie leukoencephalopathies. Leukoencephalopathies pose a particular diagnostic problem ...when they occur in children. To seek associated, non-neurologic signs is of fundamental importance in hypomyelinating leukoencephalopathies, because these can help clarify the diagnostic picture. Two new types of leukoencephalopathy have emerged, one classified as ataxia, delayed dentition, and hypomyelination, and the other as hypomyelination with hypogonadotropic hypogonadism and hypodontia. Initially described as distinct entities, they were recently brought together in the Online Mendelian Inheritance in Man database under a single code. However, the literature describes only two patients with the characteristics of both these clinical pictures. We present the extended clinical and neuroradiologic follow-up of a patient with ataxia, delayed dentition, and hypomyelination, as well as hypogonadotropic hypogonadism. This patient reinforces the idea that the two syndromes should actually be considered the same disorder, and prompted us to conduct a critical review of the literature on disorders in which hypomyelinating leukoencephalopathy is associated with cerebellar atrophy or hypogonadism.
The GLAST LAT tracker construction and test Belli, F.; Andreanelli, L.; Angelini, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2007, Letnik:
570, Številka:
2
Journal Article
Recenzirano
GLAST is a next generation high-energy gamma-ray observatory designed for making observations of celestial gamma-ray sources in the energy band extending from 10
KeV to more than 300
GeV. Respect to ...the previous instrument EGRET, GLAST will have a higher effective area (six times more), higher field of view, energy range and resolution, providing an unprecedented advance in sensitivity (a factor 30 or more). The main scientific goals are the study of all gamma-ray sources such as blazars, gamma-ray bursts, supernova remnants, pulsars, diffuse radiation, and unidentified high-energy sources. The construction and test of the Large Area Telescope (LAT) tracker, has been a great effort during the past years, involving tens of people from many Italian INFN sections and industrial partners. Environmental and performance tests of the hardware, detectors and reading electronics, have been carried on during all the steps of the LAT construction. The resulting LAT performance are better than the ones required by the original science proposal, demonstrating the quality of the italian group effort. In this article we summarize the LAT construction and test workflow, presenting its main results.
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