294 research outputs found

    Simulation and experimental evaluation of a flexible time triggered ethernet architecture applied in satellite nano/micro launchers

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    The success of small satellites has led to the study of new technologies for the realization of Nano and Micro Launch Vehicle (NMLV) in order to make competitive launch costs. The paper has the objective to define and experimentally investigate the performance of a communication system for NMLV interconnecting the End Systems as On-Board Computer (OBC), telemetry apparatus, Navigation Unit...we propose a low cost Ethernet-based solution able to provide the devices with high interconnection bandwidth. To guarantee hard delays to the Guide, Navigation and Control applications we propose some architectural changes of the traditional Ethernet network with the introduction of a layer implemented in the End Systems and allow for the lack of any contention on the network links. We show how the proposed solution has comparable performance to the one of TTEthernet standard that is a very expensive solution. An experimental test-bed equipped with Ethernet switches and Hercules boards by Texas Instruments is also provided to prove the feasibility of the proposed solution

    Retromode imaging modality of epiretinal membranes

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    (1) Purpose: To determine the characteristics of macular epiretinal membranes (ERM) using non-invasive retromode imaging (RMI) and to compare retromode images with those acquired via fundus autofluorescence (FAF) and fundus photography. (2) Methods: Prospective observational case-series study including patients with macular ERM with no other ocular disease affecting their morphology and/or imaging quality. We compared RMI, FAF and fundus photography features by cropping and overlapping images to obtain topographic correspondence. (3) Results: In total, 21 eyes (21 patients) affected by ERM were included in this study. The mean area of retinal folds detected by RMI was significantly higher than that detected by FAF (11.85 ± 3.92 mm2 and 5.67 ± 2.15 mm2, respectively, p < 0.05) and similar to that revealed by fundus photography (11.85 ± 3.92 mm2 and 10.58 ± 3.45 mm2, respectively, p = 0.277). (4) Conclusions: RMI appears to be a useful tool in the evaluation of ERMs. It allows for an accurate visualization of the real extension of the retinal folds and provides a precise structural assessment of the macula before surgery. Clinicians should be aware of RMI's advantages and should be able to use them to warrant a wide range of information and, thus, a more personalized therapeutic approach

    Sildenafil Reduces Expression and Release of IL-6 and IL-8 Induced by Reactive Oxygen Species in Systemic Sclerosis Fibroblasts

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    Oxidative stress linked to vascular damage plays an important role in the pathogenesis of systemic sclerosis (SSc). Indeed, vascular damage at nailfold capillaroscopy in patients with Raynaud’s Phenomenon (RP) is a major risk factor for the development of SSc together with the presence of specific autoantiobodies. Here, we investigated the effects of the phosphodiesterase type 5 inhibitor (PDE5i) sildenafil, currently used in the management of RP, in modulating the proinflammatory response of dermal fibroblasts to oxidative stress in vitro. Human fibroblasts isolated from SSc patients and healthy controls were exposed to exogenous reactive oxygen species (ROS) (100 µM H2O2), in the presence or absence of sildenafil (1 µM). Treatment with sildenafil significantly reduced dermal fibroblast gene expression and cellular release of IL-6, known to play a central role in the pathogenesis of tissue damage in SSc and IL-8, directly induced by ROS. This reduction was associated with suppression of STAT3-, ERK-, NF-κB-, and PKB/AKT-dependent pathways. Our findings support the notion that the employment of PDE5i in the management of RP may be explored for its efficacy in modulating the oxidative stress-induced proinflammatory activation of dermal fibroblasts in vivo and may ultimately aid in the prevention of tissue damage caused by SSc

    Optical Coherence Tomography Angiography to estimate early retinal blood flow changes after uncomplicated cataract surgery

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    Background: To investigate macular microvascular changes after uncomplicated phacoemulsification surgery according to the cataract severity grade. Methods: Retrospective, cross-sectional study involving 23 eyes of 23 patients who underwent elective cataract extraction. All patients underwent routine ophthalmologic examination, including optical coherence tomography angiography (OCTA) at baseline (preoperative visit, T0) and seven days postoperatively (T7). OCTA scans were obtained with the spectral domain system Cirrus 5000 (Carl Zeiss Meditec, Inc., Dublin, CA, USA), and 3 mm × 3 mm raster fovea-centered scans were obtained to evaluate the superficial capillary plexus (SCP) vessel density, perfusion density, and foveal avascular zone (FAZ) parameters. Results: SCP perfusion density significantly increased from 28.3 ± 5.73% to 33.74 ± 4.13% after the surgery (p < 0.001). Similarly, SCP vessel density significantly increased from 15.14 ± 3.41 mm-1 to 18.14 ± 2.57 mm-1 after surgery (p < 0.001). The mean preoperative FAZ area significantly increased from 0.27 ± 0.12 mm to 0.24 ± 0.11 mm seven days postoperatively (p = 0.008). When comparing softer and harder cataracts, no significant variations in SCP vessel density, as well as SCP perfusion density parameters and the FAZ area, perimeter, and circularity index, were noted before and after surgery. Conclusions: Macular SPC vessel density and macular SCP perfusion density increase after uncomplicated cataract surgery regardless of the cataract severity

    Insertion of a foldable hydrophobic IOL through the trabeculectomy fistula in cases with Microincision cataract surgery combined with trabeculectomy

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    BACKGROUND: The use of conventional foldable hydrophobic intraocular lenses (IOLs) in microincision cataract surgery (MICS) currently requires wound enlargement. We describe a combined surgical technique of MICS and trabeculectomy with insertion of a foldable IOL through the trabeculectomy fistula. METHODS: After completion of MICS through two side port incisions, a 3.2 mm keratome is used to enter the anterior chamber under the previously outlined scleral flap. An Acrysof multi piece IOL (Alcon labs, Fort Worth, Tx) is inserted into the capsular bag through this incision. The scleral flap is then elevated and a 2 Ă— 2 mm fistula made with a Kelly's punch. The scleral flap and conjunctival closure is performed as usual. RESULTS: Five patients with primary open angle glaucoma with a visually significant cataract underwent the above mentioned procedure. An IOL was implated in the capsular bag in all cases with no intraperative complications. After surgery, all patients obtained a best corrected visual acuity of 20/20, IOL was well centered at 4 weeks follow up. The mean IOP (without any antiglaucoma medication) was 13.2 + 2.4 mm Hg at 12 weeks with a well formed diffuse filtering bleb in all the cases. CONCLUSION: The technique of combining MICS with trabeculectomy and insertion of a foldable IOL through the trabeculectomy fistula is a feasible and valuable technique for cases which require combined cataract and glaucoma surgery

    Comparison of Blue Light-Filtering IOLs and UV Light-Filtering IOLs for Cataract Surgery: A Meta-Analysis

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    Background: A number of published randomized controlled trials have been conducted to evaluate visual performance of blue light-filtering intraocular lenses (IOL) and UV light-filtering intraocular lenses (IOL) after cataract phacoemulsification surgery. However, results have not always been consistent. Therefore, we carried out a meta-analysis to compare the effectiveness of blue light-filtering IOLs versus UV light-filtering IOLs in cataract surgery. Methods and Findings: Comprehensive searches of PubMed, Embase, Cochrane Library and the Chinese BioMedical literature databases were performed using web-based search engines. Fifteen trials (1690 eyes) were included for systematic review, and 11 of 15 studies were included in this meta-analysis. The results showed that there were no significant differences in postoperative mean best corrected visual acuity, contrast sensitivity, overall color vision, or in the blue light spectrum under photopic light conditions between blue light-filtering IOLs and UV light-filtering IOLs [WMD = 20.01, 95%CI (20.03, 0.01), P = 0.46; WMD = 0.07, 95%CI (20.04, 0.19), P = 0.20; SMD = 0.14, 95%CI (20.33, 0.60), P = 0.566; SMD = 0.20, 95%CI (20.04, 0.43), P = 0.099]. However, color vision with blue light-filtering IOLs was significantly reduced in the blue light spectrum under mesopic light conditions [SMD = 0.74, 95%CI (0.29, 1.18), P = 0.001]. Conclusion: This meta-analysis demonstrates that postoperative visual performance with blue light-filtering IOLs is approximately equal to that of UV light-filtering IOLs after cataract surgery, but color vision with blue light-filtering IOL

    Analyse automatique des données scripturales prétraitées par des outils de visualization

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    RÉSUMÉ: Plusieurs méthodes pour analyser le processus d'écriture ont été utilisés afin de comprendre les stratégies des scripteurs. L'outil principal pour analyser le processus d'écriture est le fichier log, qui contient de façon exhaustive et détaillée l'ensemble des opérations effectuées par le scripteur lors de la rédaction d'un texte. Les données qui y sont emmagasinées sont de quantité considérable et lorsqu'elles ne sont pas préalablement traitées, elles sont hostiles à être analysées par l'humain. Parmi les outils d'analyse utilisés, les représentations du processus d'écriture permettent l'agrégation des données grâce à un pré-traitement. Les structures sous-jacentes des données ainsi représentées sont généralement plus propices à l'analyse que les données brutes. Cet article vise à démontrer différentes méthodes d'analyse automatique pouvant être appliquées à ces structures afin de trouver ou confirmer des structures et tendances à travers les données. ABSTRACT: Several methods to analyze the writing process were used in order to understand the strategies of the writers. The main tool to analyze the writing process is the log file which contains all the operations performed by the writer when writing a text, in a comprehensive and detailed way. The data stored in it is of considerable amount and when not previously treated, it is not made to be analyzed by humans. Among the analytical tools used, the representations of the writing process allow aggregation of data through a pre-treatment. The underlying data structures as shown by these tools are generally conducive to analyzing the raw data afterwards. This article aims to demonstrate various automatic analysis methods that can be applied to these structures to find or confirm the structures and trends through data

    Sam68 splicing regulation contributes to motor unit establishment in the postnatal skeletal muscle

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    RNA-binding proteins orchestrate the composite life of RNA molecules and impact most physiological processes, thus underlying complex phenotypes. The RNA-binding protein Sam68 regulates differentiation processes by modulating splicing, polyadenylation, and stability of select transcripts. Herein, we found that Sam68-/- mice display altered regulation of alternative splicing in the spinal cord of key target genes involved in synaptic functions. Analysis of the motor units revealed that Sam68 ablation impairs the establishment of neuromuscular junctions and causes progressive loss of motor neurons in the spinal cord. Importantly, alterations of neuromuscular junction morphology and properties in Sam68-/- mice correlate with defects in muscle and motor unit integrity. Sam68-/- muscles display defects in postnatal development, with manifest signs of atrophy. Furthermore, fast-twitch muscles in Sam68-/- mice show structural features typical of slow-twitch muscles, suggesting alterations in the metabolic and functional properties of myofibers. Collectively, our data identify a key role for Sam68 in muscle development and suggest that proper establishment of motor units requires timely expression of synaptic splice variants
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