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BackgroundRetinal imaging has been applied for detecting eye diseases and cardiovascular risks using deep learning–based methods. Furthermore, retinal microvascular and structural changes were found in renal function impairments. However, a deep learning–based method using retinal images for detecting early renal function impairment has not yet been well studied. ObjectiveThis study aimed to develop and evaluate a deep learning model for detecting early renal function impairment using retinal fundus images. MethodsThis retrospective study enrolled patients who underwent renal function tests with color fundus images captured at any time between January 1, 2001, and August 31, 2019. A deep learning model was constructed to detect impaired renal function from the images. Early renal function impairment was defined as estimated glomerular filtration rate 6.5%, >7.5%, and >10%, respectively. ConclusionsThe deep learning model in this study enables the detection of early renal function impairment using retinal fundus images. The model was more accurate for patients with elevated serum HbA1c levels.

In this article, we propose an efficient reference-based deep in-loop filtering method for video coding. Existing reference-based in-loop filters often face challenges in improving coding efficiency due to the difficulty in capturing relevant textures from the reference frames. Our method accurately predicts the texture of a reference block and uses this information to restore the current block. To achieve this, we develop a reference-to-current feature estimation module that conveys high-quality information from previously coded frames in the feature domain, thereby preventing loss of detail due to inaccurate prediction. Although a neural network is trained to restore a coded video frame to be similar to the current frame, their performance can significantly degrade when operating with various quantization parameters (QPs) and managing different levels of distortion. This problem becomes further severe in the reference-to-current feature estimation, in which QP values are applied differently to video frames. We address this problem by developing a QP-aware convolution layer with a small number of learnable parameters to generate reliable features and adapt to fine-grained adaptive QPs among consecutive frames. The proposed method is implemented into the versatile video coding (VVC) reference software, VTM version 10.0. Experimental results demonstrate that the proposed method improves coding performance significantly in VVC. [ABSTRACT FROM AUTHOR]

This paper examines the deviation of refueling a hydrogen fuel cell vehicle with limited opportunity provided by the 68 proposed stations in California. A refueling trip is inserted to reported travel patterns in early hydrogen adoption community clusters and the best and worst case insertions are analyzed. Based on these results, the 68 refueling stations provide an average of 2.5 and 9.6 min deviation for the best and the worst cases. These numbers are comparable to currently observed gasoline station deviation, and we conclude that these stations provide sufficient accessibility to residents in the target areas. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserver.

A transition from gasoline internal combustion engine vehicles to hydrogen fuel cell electric vehicles (FCEVs) is likely to emerge as a major component of the strategy to meet future greenhouse gas reduction, air quality, fuel independence, and energy security goals. Advanced infrastructure planning can minimize the cost of hydrogen infrastructure while assuring that energy and environment benefits are achieved. This study presents a comprehensive advanced planning methodology for the deployment of hydrogen infrastructure, and applies the methodology to delineate fully built-out infrastructure strategies, assess the associated energy and environment impacts, facilitate the identification of an optimal infrastructure roll-out strategy, and identify the potential for renewable hydrogen feedstocks. The South Coast Air Basin of California, targeted by automobile manufacturers for the first regional commercial deployment of FCEVs, is the focus for the study. The following insights result from the application of the methodology:Compared to current gasoline stations, only 11%-14% of the number of hydrogen fueling stations can provide comparable accessibility to drivers in a targeted region.To meet reasonable capacity demand for hydrogen fueling, approximately 30% the number of hydrogen stations are required compared to current gasoline stations.Replacing gasoline vehicles with hydrogen FCEVs has the potential to (1) reduce the emission of greenhouse gases by more than 80%, reduce energy requirements by 42%, and virtually eliminate petroleum consumption from the passenger vehicle sector, and (2) significantly reduce urban concentrations of ozone and PM2.5.Existing sources of biomethane in the California South Coast Air Basin can provide up to 30% of the hydrogen fueling demand for a fully built-out hydrogen FCEV scenario.A step-wise transition of judiciously located existing gasoline stations to dispense and accommodate the increasing demand for hydrogen addresses proactively key infrastructure deployment challenges including a viable business model, zoning, permitting, and public acceptance. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

The introduction of hydrogen infrastructure and fuel cell vehicles (FCVs) to gradually replace gasoline internal combustion engine vehicles can provide environment and energy security benefits. The deployment of hydrogen fueling infrastructure to support the demonstration and commercialization of FCVs remains a critical barrier to transitioning to hydrogen as a transportation fuel. This study utilizes an engineering methodology referred to as the Spatially and Temporally Resolved Energy and Environment Tool (STREET) to demonstrate how systematic planning can optimize early investments in hydrogen infrastructure in a way that supports and encourages growth in the deployment of FCVs while ensuring that the associated environment and energy security benefits are fully realized. Specifically, a case study is performed for the City of Irvine, California - a target area for FCV deployment - to determine the optimized number and location of hydrogen fueling stations required to provide a bridge to FCV commercialization, the preferred rollout strategy for those stations, and the environmental impact associated with three near-term scenarios for hydrogen production and distribution associated with local and regional sources of hydrogen available to the City. Furthermore, because the State of California has adopted legislation imposing environmental standards for hydrogen production, results of the environmental impact assessment for hydrogen production and distribution scenarios are measured against the California standards. The results show that significantly fewer hydrogen fueling stations are required to provide comparable service to the existing gasoline infrastructure, and that key community statistics are needed to inform the preferred rollout strategy for the stations. Well-to-wheel (WTW) greenhouse gas (GHG) emissions, urban criteria pollutants, energy use, and water use associated with hydrogen and FCVs can be significantly reduced in comparison to the average parc of gasoline vehicles regardless of whether hydrogen is produced and distributed with an emphasis on conventional resources (e.g., natural gas), or on local, renewable resources. An emphasis on local renewable resources to produce hydrogen further reduces emissions, energy use, and water use associated with hydrogen and FCVs compared to an emphasis on conventional resources. All three hydrogen production and distribution scenarios considered in the study meet California's standards for well-to-wheel GHG emissions, and well-to-tank emissions of urban ROG and NOX. Two of the three scenarios also meet California's standard that 33% of hydrogen must be produced from renewable feedstocks. Overall, systematic planning optimizes both the economic and environmental impact associated with the deployment of hydrogen infrastructure and FCVs. © 2010 Professor T. Nejat Veziroglu.

Aims: Sodium–glucose cotransporter‐2 inhibitors (SGLT2is) are proposed to alleviate the development of inflammatory eye diseases. However, the association between SGLT2i and retinal vascular occlusion remains unclear. Therefore, this study aims to explore the effects of SGLT2i on the incidence of retinal vascular occlusion. Materials and Methods: This retrospective cohort study analysed electronic medical records data from the largest multi‐institutional database in Taiwan. Individuals who initiated SGLT2is and dipeptidyl peptidase 4 inhibitors (DPP4is) between 2016 and 2019 were included in our analysis. To conduct a homogenous comparison, inverse probability of treatment weighting with propensity scoring was employed. The primary outcome was retinal vascular occlusion, and the secondary outcomes were retinal vascular occlusion‐related complications (macular oedema, vitreous haemorrhage, and tractional retinal detachment) and conditions requiring vitreoretinal intervention (intravitreal injection, retinal laser therapy, and vitrectomy). Results: In total, 12,074 SGLT2i users and 39,318 DPP4i users were included. The incidence rate of retinal vascular occlusion in the SGLT2i and DPP4i groups was 1.2 (95% confidence interval [CI], 0.9–1.4) and 1.6 (95% CI, 1.3–1.8) events per 1000 person‐years, respectively, which yielded a subdistribution hazard ratio (SHR) of 0.74 (95% CI, 0.55–0.99). Similar risk reductions were observed in the retinal vascular occlusion‐related complications (SHR, 0.76; 95% CI, 0.69–0.84) and conditions requiring vitreoretinal intervention (SHR, 0.84; 95% CI, 0.77–0.94). Conclusions: In this multi‐institutional study in Taiwan, SGLT2i use was associated with a reduced risk of retinal vascular occlusion. Further prospective studies are required to ascertain this association. [ABSTRACT FROM AUTHOR]