Supporting novel home network management interfaces with Openflow and NOX

The Homework project has examined redesign of existing home network infrastructures to better support the needs and requirements of actual home users. Integrating results from several ethnographic studies, we have designed and built a home networking platform providing detailed per-flow measurement and management capabilities supporting several novel management interfaces. This demo specifically shows these new visualization and control interfaces, and describes the broader benefits of taking an integrated view of the networking infrastructure, realised through our router's augmented measurement and control APIs. Aspects of this work have been published: the Homework Database in Internet Management (IM) 2011 and implications of the ethnographic results are to appear at the SIGCOMM W-MUST workshop 2011. Separate, more detailed expositions of the interface elements and system performance and implications are currently under submission at other venues. A partial code release is already available and we anticipate fuller public beta release by Q4 2011

A comparison of manifest refractions, cycloplegic refractions and retinoscopy on the RMA-3000 autorefractometer in children aged 3 to 15 years

T Rotsos,1 D Grigoriou,2 A Kokkolaki,2 N Manios21Moorfields eye hospital, London, UK; 2Department of Ophthalmology, General Children’s Hospital, Penteli, Athens, GreecePurpose: The study was conducted to compare the accuracy of readings of the RMA-3000 autorefractometer (Topcon, Tokyo, Japan) with traditional retinoscopy as a means of determining the approximate subjective refraction in children after cycloplegia.Methods: 142 children aged 3 to 15 years were included. All children had their refractive status measured with the RMA-3000 autorefractometer (noncycloplegic autorefraction [AR]). Subsequently all children underwent cycloplegia and the refractive status was estimated again with the autorefractometer (cycloplegic autorefraction [ARC]) and traditional retinoscopy (RC) by examiners who were unaware of the results from the other techniques.Results: From 69 right eyes with negative sphere we observed that the sphere power was significantly higher (more than 0.5 diopters) in AR than in ARC (P = 0.0001) and RC (P = 0.0001). From the 73 normal and hyperopic right eyes we observed that the sphere power was significantly lower (more than 0.5 diopters) in AR than in ARC (P = 0.0001) and RC (P = 0.0001). Conclusions: The use of the autorefractometer in children (in whom accommodation is more active than older patients) without cycloplegia may underestimate the actual hyperopia and overestimate the actual myopia. Manual retinoscopy is still the most accurate technique to estimate refractive status in children.Keywords: refractometer, cycloplegia, retinoscopy, myopia, hyperopia, astigmatis

Supporting novel home network management interfaces with Openflow and NOX

The Homework project has examined redesign of existing home network infrastructures to better support the needs and requirements of actual home users. Integrating results from several ethnographic studies, we have designed and built a home networking platform providing detailed per-flow measurement and management capabilities supporting several novel management interfaces. This demo specifically shows these new visualization and control interfaces, and describes the broader benefits of taking an integrated view of the networking infrastructure, realised through our router's augmented measurement and control APIs. Aspects of this work have been published: the Homework Database in Internet Management (IM) 2011 and implications of the ethnographic results are to appear at the SIGCOMM W-MUST workshop 2011. Separate, more detailed expositions of the interface elements and system performance and implications are currently under submission at other venues. A partial code release is already available and we anticipate fuller public beta release by Q4 2011

Extending the phenotypic spectrum of PRPF8, PRPH2, RP1 and RPGR, and the genotypic spectrum of early-onset severe retinal dystrophy

PURPOSE: To present the detailed retinal phenotype of patients with Leber Congenital Amaurosis/Early-Onset Severe Retinal Dystrophy (LCA/EOSRD) caused by sequence variants in four genes, either not (n = 1) or very rarely (n = 3) previously associated with the disease. METHODS: Retrospective case series of LCA/EOSRD from four pedigrees. Chart review of clinical notes, multimodal retinal imaging, electrophysiology, and molecular genetic testing at a single tertiary referral center (Moorfields Eye Hospital, London, UK). RESULTS: The mean age of presentation was 3 months of age, with disease onset in the first year of life in all cases. Molecular genetic testing revealed the following disease-causing variants: PRPF8 (heterozygous c.5804G > A), PRPH2 (homozygous c.620_627delinsTA, novel variant), RP1 (homozygous c.4147_4151delGGATT, novel variant) and RPGR (heterozygous c.1894_1897delGACA). PRPF8, PRPH2, and RP1 variants have very rarely been reported, either as unique cases or case reports, with limited clinical data presented. RPGR variants have not previously been associated with LCA/EOSRD. Clinical history and detailed retinal imaging are presented. CONCLUSIONS: The reported cases extend the phenotypic spectrum of PRPF8-, PRPH2-, RP1-, and RPGR-associated disease, and the genotypic spectrum of LCA/EOSRD. The study highlights the importance of retinal and functional phenotyping, and the importance of specific genetic diagnosis to potential future therapy

GUCY2D-Associated Leber Congenital Amaurosis: A Retrospective Natural History Study in Preparation for Trials of Novel Therapies

Purpose To describe the natural history of Leber congenital Amaurosis (LCA) associated with GUCY2D variants (GUCY2D-LCA) in a cohort of children and adults, in preparation for trials of novel therapies. Design Retrospective case series. Participants Patients with GUCY2D-LCA at a single referral center. Methods Review of clinical notes, retinal imaging including fundus autofluorescence (FAF), and optical coherence tomography (OCT), electroretinography (ERG), and molecular genetic testing. Main Outcome Measures Demographic data, symptoms at presentation, visual acuity, evidence of progression, OCT and FAF findings, ERG assessment and molecular genetics. Results Twenty-one subjects with GUCY2D-LCA were included, with a mean follow up ± standard deviation (SD) of 10 ± 11.85 years. Marked reduction in visual acuity (VA) and nystagmus was documented in all patients within the first 3 years of life. Fifty-four percent (n=12) exhibited photophobia and 36% (n=8) had nyctalopia. VA was worse than hand motion in 71% of the patients (n=15). Longitudinal assessment of VA showed stability in all patients, except one patient who experienced deterioration over a follow-up of 44 years. Hyperopia was reported in 13 (71%) of the 17 subjects with available refraction data. Eighteen subjects had either normal fundus appearance (n=14) or a blonde fundus (n=3), while only 4 of the eldest subjects had mild RPE atrophy (mean, 49 years; range 40 - 54 years). OCT data were available for eleven subjects and four different grades of ellipsoid zone (EZ) integrity were identified: (i) continuous/intact EZ (n=6), (ii) focally disrupted EZ (n=2), (iii) focally disrupted with RPE changes (n=2), and (iv) diffuse EZ disruption with RPE changes (n=1). All examined subjects had stable OCT findings over the long follow-up period. Full-field ERGs showed evidence of a severe cone-rod dystrophy in 5 of 6 patients, and undetectable ERGs in one subject. Novel genotype-phenotype correlations are also reported. Conclusion GUCY2D-LCA is a severe early-onset retinal dystrophy associated with very poor VA from birth. Despite the severely affected photoreceptor function, the relatively preserved photoreceptor structure based on EZ integrity till late in the disease in the majority of subjects, suggests a wide therapeutic window for gene therapy trials

Spontaneous traumatic macular hole closure in a 50-year-old woman: a case report

<p>Abstract</p> <p>Introduction</p> <p>Traumatic macular holes (TMH) are well-known complications of ocular contusion injury. Spontaneous closure occurs in approximately 50% of cases, but rarely after the age of thirty. We report a case of spontaneous closure of a full thickness macular hole due to a blunt trauma and we suggest possible mechanisms for this closure.</p> <p>Case presentation</p> <p>A 50-year-old Greek woman was referred with a history of reduced best-corrected visual acuity after blunt trauma to her right eye. Diagnosis was based on fundoscopic, optical coherence tomography as well as fluorescein angiography findings with follow-up visits at two days, 20 days and five months. Fundoscopy revealed a full-thickness TMH with a minor sub-retinal hemorrhage and posterior vitreous detachment. The presence of a coagulum in the TMH base was observed. Subsequently, TMH closure was observed.</p> <p>Conclusion</p> <p>The clot in the TMH base, potentially a hemorrhage by-product containing a significant quantity of platelets, may have simulated the clot observed after autologous serum use, thus facilitating a similar effect. This may have stimulated glial cell migration and proliferation, thus contributing to spontaneous hole closure.</p

OFLOPS: An Open Framework for OpenFlow Switch Evaluation

Abstract. Recent efforts in software-defined networks, such as OpenFlow, give unprecedented access into the forwarding plane of networking equipment. When building a network based on OpenFlow however, one must take into account the performance characteristics of particular OpenFlow switch implementations. In this paper, we present OFLOPS, an open and generic software framework that permits the development of tests for OpenFlow-enabled switches, that measure the capabilities and bottlenecks between the forwarding engine of the switch and the remote control application. OFLOPS combines hardware instrumentation with an extensible software framework. We use OFLOPS to evaluate current OpenFlow switch implementations and make the following observations: (i) The switching performance of flows depends on applied actions and firmware. (ii) Current OpenFlow implementations differ substantially in flow updating rates as well as traffic monitoring capabilities. (iii) Accurate OpenFlow command completion can be observed only through the data plane. These observations are crucial for understanding the applicability of Open-Flow in the context of specific use-cases, which have requirements in terms of forwarding table consistency, flow setup latency, flow space granularity, packet modification types, and/or traffic monitoring abilities.

A fingerprint hidden inside the eye. A unique pattern of outer retina splitting as seen on en-face OCT and OCT-angiography

A splitting of the outer plexiform retinal layer in a saw-like hyporeflective pattern in addition to partially formed concentric circles centred at the foveola were observed using en-face OCT and OCT-angiography in a 27-year-old female patient with rhegmatogenous retinal detachment and a 50-year-old female patient with Vogt-Koyanagi-Harada chorioretinopathy. © 202

Optical coherence tomography angiography and multifocal electroretinogram findings in paracentral acute middle maculopathy

Paracentral acute middle maculopathy (PAMM) is an optical coherence tomography (OCT) finding seen in patients with retinal capillary ischemia. In this case report, we present a case of PAMM after a transient central retinal artery occlusion and the multifocal electroretinogram (mfERG) and other multimodal imaging findings. Clinical examination, OCT angiography, OCT en face, fluorescein angiography, and visual fields were performed at the baseline and follow-up examinations. As a result, we identified in this PAMM case evidence of hypoperfusion in both the choriocapillaris as well as the deep capillary plexus. To the best of our knowledge, the involvement of choriocapillaris has not been reported previously in the literature. Moreover, we concluded that mfERG constitutes a useful investigation in PAMM and this is the first mfERG findings to be presented for a PAMM case specifically. © 2020 Wolters Kluwer Medknow Publications. All rights reserved