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1.
IEEE Trans Image Process ; 33: 3314-3327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709600

RESUMO

Traditional block-based spatially scalable video coding has been studied for over twenty years. While significant advancements have been made, the scope for further improvement in compression performance is limited. Inspired by the success of learned video coding, we propose an end-to-end learned spatially scalable video coding scheme, LSSVC, which provides a new solution for scalable video coding. In LSSVC, we propose to use the motion, texture, and latent information of the base layer (BL) as interlayer information for compressing the enhancement layer (EL). To reduce interlayer redundancy, we design three modules to leverage the upsampled interlayer information. Firstly, we design a contextual motion vector (MV) encoder-decoder, which utilizes the upsampled BL motion information to help compress high-resolution MV. Secondly, we design a hybrid temporal-layer context mining module to learn more accurate contexts from the EL temporal features and the upsampled BL texture information. Thirdly, we use the upsampled BL latent information as an interlayer prior for the entropy model to estimate more accurate probability distribution parameters for the high-resolution latents. Experimental results show that our scheme surpasses H.265/SHVC reference software by a large margin. Our code is available at https://github.com/EsakaK/LSSVC.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38252583

RESUMO

Almost all digital videos are coded into compact representations before being transmitted. Such compact representations need to be decoded back to pixels before being displayed to humans and -as usual- before being enhanced/analyzed by machine vision algorithms. Intuitively, it is more efficient to enhance/analyze the coded representations directly without decoding them into pixels. Therefore, we propose a versatile neural video coding (VNVC) framework, which targets learning compact representations to support both reconstruction and direct enhancement/analysis, thereby being versatile for both human and machine vision. Our VNVC framework has a feature-based compression loop. In the loop, one frame is encoded into compact representations and decoded to an intermediate feature that is obtained before performing reconstruction. The intermediate feature can be used as reference in motion compensation and motion estimation through feature-based temporal context mining and cross-domain motion encoder-decoder to compress the following frames. The intermediate feature is directly fed into video reconstruction, video enhancement, and video analysis networks to evaluate its effectiveness. The evaluation shows that our framework with the intermediate feature achieves high compression efficiency for video reconstruction and satisfactory task performances with lower complexities.

3.
Neuropsychiatr Dis Treat ; 18: 2265-2271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36268267

RESUMO

Purpose: This study aims to investigate the prognostic value of the peripheral neutrophil-to-lymphocyte ratio (NLR) in patients with chronic internal carotid artery occlusion (CICAO) complicated by cerebral infarction. Patients and Methods: The clinical data of 99 CICAO patients complicated by cerebral infarction were retrospectively analyzed. The modified Rankin Scale (mRS) was used to assess their 3-month prognosis, and a multivariate logistic regression model was established to explore risk factors for poor prognosis. Results: Multivariate logistic regression analysis demonstrated that NLR (OR=2.114; 95% CI: 1.129-3.959) and baseline National Institute of Health Stroke Scale (NIHSS; OR=1.288, 95% CI: 1.053-1.574) score were risk factors of poor prognosis. The area under the receiver operator characteristic (ROC) curve of NLR in predicting the 3-month outcome after onset was 0.717 (95% CI: 0.606-0.828, P<0.000). The optimal cut-off value was 3.22, with a sensitivity of 0.743 and a specificity of 0.791. Conclusion: NLR is an independent risk factor for the poor prognosis of CICAO patients complicated by cerebral infarction and can serve as an indicator for clinical prognosis.

4.
IEEE Trans Image Process ; 31: 3399-3413, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35503831

RESUMO

Geometry-based point cloud compression (G-PCC) can achieve remarkable compression efficiency for point clouds. However, it still leads to serious attribute compression artifacts, especially under low bitrate scenarios. In this paper, we propose a Multi-Scale Graph Attention Network (MS-GAT) to remove the artifacts of point cloud attributes compressed by G-PCC. We first construct a graph based on point cloud geometry coordinates and then use the Chebyshev graph convolutions to extract features of point cloud attributes. Considering that one point may be correlated with points both near and far away from it, we propose a multi-scale scheme to capture the short- and long-range correlations between the current point and its neighboring and distant points. To address the problem that various points may have different degrees of artifacts caused by adaptive quantization, we introduce the quantization step per point as an extra input to the proposed network. We also incorporate a weighted graph attentional layer into the network to pay special attention to the points with more attribute artifacts. To the best of our knowledge, this is the first attribute artifacts removal method for G-PCC. We validate the effectiveness of our method over various point clouds. Objective comparison results show that our proposed method achieves an average of 9.74% BD-rate reduction compared with Predlift and 10.13% BD-rate reduction compared with RAHT. Subjective comparison results present that visual artifacts such as color shifting, blurring, and quantization noise are reduced.

5.
Neuropsychiatr Dis Treat ; 17: 1977-1982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34168455

RESUMO

OBJECTIVE: This study aimed to investigate the relationship between serum total bilirubin (TBil) level and early neurological deterioration (END) in patients with acute ischemic stroke of large artery atherosclerosis. PATIENTS AND METHODS: In this retrospective study, a total of 291 patients with acute ischemic stroke were enrolled. The demographic and laboratory dates were collected. Stroke severity had been assessed using the National Institutes of Health Stroke Scale (NIHSS). Multivariable logistic regression was used to examine the independent association between TBil and END. RESULTS: Approximately 63 (21.6%) of the patients were diagnosed with END within the first seven days. The proportion of hypertension, diabetes mellitus (DM) and previous stroke/transient ischemic attack (TIA) was significant greater in the lowest quartile (<9.8 µmol/l) of TBil. The proportion of patients with an elevated TBil levels was significantly lower in the END group than in the non-END group. After controlling for covariates, the first quartiles (<9.8 µmol/l) of TBil were still associated with END. In addition, an increased level of CRP and age were also associated with an increased risk of END. CONCLUSION: The TBil levels in patients with acute cerebral infarction may be a useful biomarker for the prediction of END.

6.
J Stroke Cerebrovasc Dis ; 30(8): 105674, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34119749

RESUMO

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), which is caused by the Notch3 gene mutation, has its unique clinical and imaging characteristics. Here we present a Chinese family with a novel mutation on exon 10 of Notch3 gene. METHODS: Clinical and MRI data of the three patients in the family during the 7-year follow-up were collected. The CADASIL Scale Score was calculated to evaluate the disease risk of the three patients at their first admission or clinic visit. Five family members underwent genetic test. RESULTS: Genetic test confirmed the diagnosis of CADASIL in this family. A novel mutation of p.C533S on exon 10 of Notch3 gene was detected. The CADASIL score of the proband and her sister was both 17 and that of her brother was 14. CONCLUSIONS: Our report not only expands the mutation spectrum of Notch3 gene in CADASIL, but also shows the distinct heterogeneity of CADASIL patients in the same family with the same mutation.


Assuntos
CADASIL/genética , Mutação de Sentido Incorreto , Receptor Notch3/genética , Adulto , Povo Asiático/genética , CADASIL/diagnóstico , CADASIL/etnologia , China , Análise Mutacional de DNA , Éxons , Feminino , Predisposição Genética para Doença , Hereditariedade , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo
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