Underwater image restoration via adaptive color correction and dehazing.

Due to the absorbing and scattering effects, underwater images are often degraded by low contrast, color cast, and haze, which have limited their further applications to underwater vision task. To address this issue, we propose a hybrid framework by adaptive color correction and dehazing for underwater image restoration. Specifically, according to the color attenuation principle, we first design an adaptive color compensation strategy to correct the color cast of the underwater image. In addition, based on an underwater image formation model, we develop a robust dehazing algorithm, in which a new scoring formula across three indicators (i.e., darkness, distance, and blurriness) and a double-max DCP method are proposed to estimate the background light and transmission map, respectively. The experimental results validate that the proposed method is effective in color correction and dehazing. Both qualitative and quantitative comparisons further demonstrate that the proposed method outperforms several state-of-the-art methods.

Diagnostic status and epidemiological characteristics of community-acquired bacterial meningitis in children from 2019 to 2020: a multicenter retrospective study.

Community-acquired bacterial meningitis (CABM) is the main cause of morbidity and mortality in children. The epidemiology of CABM is regional and highly dynamic. To clarify the diagnostic status and epidemiological characteristics of children with CABM in this region, and pay attention to the disease burden, so as to provide evidence for the prevention and treatment of CABM. By retrospective case analysis, the clinical data of 918 CABM cases in children aged 0-14 years in Zhejiang Province from January, 2019 to December, 2020 were collected. The etiological diagnosis rate of CABM in children was 23.1%, the annual incidence rate 4.42-6.15/100,000, the annual mortality rate 0.06-0.09/100,000,the cure and improvement rate 94.4%, and the case fatality rate 1.4%. The total incidence of neuroimaging abnormalities was 20.6%. The median length of stay for CABM children was 20(16) days, with an average cost of 21,531(24,835) yuan. In addition, the incidence rate was decreased with age. Escherichia coli(E.coli) and group B Streptococcus agalactiae(GBS) were the principal pathogens in CABM infant<3 months(43.3%, 34.1%), and Streptococcus pneumoniae(S. pneumoniae) was the most common pathogen in children ≥ 3 months(33.9%). In conclusion, the annual incidence and mortality of CABM in children aged 0-14 years in Zhejiang Province are at intermediate and low level. The distribution of CABM incidence and pathogen spectrum are different in age; the incidence of abnormal neuroimaging is high; and the economic burden is heavy.

Factors associated with afebrile presentation and delayed defervescence of bacterial meningitis in children under 3 years of age: a multi-centre retrospective analysis.

BACKGROUND: This multi-center study aimed to identify factors affecting fever and delayed defervescence in bacterial meningitis (BM) patients under 3 years of age because of the variability of fever in this patient population. METHODS: Only BM patients under 3 years treated at 49 centers in China from November 2018 to end-April 2021 were included in the study. Univariate and multivariate logistic regression analyses were performed to determine factors associated with afebrile presentation and fever of delayed defervescence. RESULTS: A total of 863 BM patients under 3 years were included in the study. Coagulase negative staphylococcus was associated with afebrile presentation (OR = 1.176), while septicaemia and ear-nose-throat infections were associated with fever (P < 0.05). The patients with fever were assigned into early and delayed defervescence groups based on defervescence time (less than and more than or equal to one week). Furthermore, Streptococcus agalactiae meningitis (OR = 1.124), concomitant gastrointestinal infection (OR = 1.276), encephalomalacia (or = 1.339), and subdural effusion (OR = 1.454) were independently associated with delayed defervescence (all P < 0.05). CONCLUSIONS: The findings can aid in the efficient utilization of fever in auxiliary diagnosis and evaluating the condition of the disease.