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Spray paint exhaust gas contains recalcitrant volatile organic compounds (VOCs), such as benzene, toluene and xylene (BTX). Treating BTX with a biofilter often achieves unsatisfactory results because the biofilter lacks efficient microbial community. In this work, three strains for BTX degradation were isolated and identified as Pseudomonas putida, Bacillus cereus and Bacillus subtilis by using 16S rRNA sequencing technology. A consortium of highly efficient microbial community was then constructed on a stable biofilm to treat BTX in a biofilter. A relatively suitable ratio of P. putida, B. cereus and B. subtilis was obtained. An efficiency of over 90% was achieved in the biofilter with VOC concentration of 1000 mg/m 3 through inoculation with the microbial community after only 10 days of operation. Thus, fast start-up of the biofilter was realised. Analysis of intermediate products by gas chromatographymass spectrometry indicated that BTX was degraded into short-chain aldehydes or acids via ring opening reactions. Paint spray exhaust gas includes volatile organic compounds (VOCs), such as benzene, toluene and xylene (BTX), and even more complicated compounds, i.e. chlorinated benzenes and toluenes 1,2 , all of which can cause great harm to humans 3,4. The indiscriminate discharge of large amounts of paint spray exhaust gas also exerts a negative impact on the atmospheric environment 5,6. Therefore, efficient technologies should be developed to treat paint spray exhaust gas and address its effects. Although several technologies for paint spray exhaust gas treatment exist, some of these methods are difficult to apply on a large scale because of their shortcomings 7. Biofiltration and biotrickling filters have received wide attention because they are low-cost and occupy a small space. Moreover, the activity of microorganisms can remain comparatively stable 8-10. Leili et al. found that the biofiltration system shows good performance in terms of removing BTEX 11. In theory, VOCs can completely mineralise during biofiltration. However, it is restricted by the microorganism type and the operating parameters in practise. Thus, the effect remains unsatisfactory 12. The toxicants in waste gas could be degraded with a specific strain by acclimation, which can be applied to the biofilters to improve their efficiency. A removal efficiency of higher than 98% was achieved by Bacillus firmus when the concentration of ketone (acetone and methyl ethyl ketone) and benzene in paint spray exhaust gas was lower than 3000 mg/m 3 13. Mohammad et al. used Exophiala sp. as inoculum for biofilter, which had a good removal effect on BTEX 14. However, because the composition of the exhaust gas might be complex, a single strain may not always obtain satisfactory results, resulting in unstable removal rates 15,16. The microbial community has been studied to promote biofilter operation. Archaea and bacteria effectively remove printing press VOCs in an anaerobic bioscrubber 17. Xue et al. used a biotrickling filter to treat complex odorous gas...

PurposeTo evaluate the diagnostic value of spectral-domain optical coherence tomography (SD-OCT) for polypoidal choroidal vasculopathy (PCV).MethodsA search of electronic databases was conducted from 2010 to 2021 to review the relevant literature on SD-OCT to identify PCV and other lesions causing serious or serosanguinous retinal pigment epithelial detachment (PED), specifically neovascular age-related macular degeneration (nvAMD). The QUADAS-2 scale was used to evaluate the quality of the literature. We performed a meta-analysis, including heterogeneity tests, analyze and synthesize the study data, meta-regression analysis, subgroup analysis, Fagan's plot, sensitivity analysis and publication bias tests.ResultsA total of 12 related studies involving 1,348 eyes were included in this study, and the random-effects model was used for meta-analysis. The results showed that the pooled sensitivity of SD-OCT in the diagnosis of PCV was 0.87 (95% CI: 0.84–0.89), the pooled specificity was 0.83 (95% CI: 0.80–0.86), and the pooled positive/negative likelihood ratios were 5.38 (95% CI: 3.28–8.80) and 0.16 (95% CI: 0.10–0.25), respectively. The diagnostic odds ratio (DOR) was 36.07 (95% CI: 15.98–81.40), and the area under the sROC curve (AUC) was 0.9429. When the pre–test probability was set at 20%, the post-test positive and negative probabilities were 58% and 4%, respectively. Meta-regression indicated that race was the primary source of heterogeneity (P <0.05). The Deeks' funnel plot showed no significant publication bias in this study (P>0.05).ConclusionSD-OCT has high sensitivity and specificity for the diagnosis of PCV, as well as significant clinical applicability. Since color fundus photography (CFP) is more clinically available and can improve the diagnostic efficacy, we recommend SD-OCT combined with CFP to diagnose PCV, especially without indocyanine green angiography (ICGA).Systematic Review Registrationhttps://inplasy.com/inplasy-2021-12-0048/, identifier: INPLASY2021120048.

White water treatment with combined predominant bacterial species and immobilized enzyme was investigated. The use of the single predominant bacteria of Brevundimonas diminuta or Virgibacillus pantothenticus resulted in poor treatment responses. With the combined bacterial species, the treatment effect was clearly improved. When the dosage ratio of Brevundimonas diminuta to Virgibacillus pantothenticus was 1:2, the chemical oxygen demand (CODCr) removal rate reached 70.5%, the cationic demand decreased 46.0%, and the electrical conductivity decreased 18.6% after 16 h of treatment. When mixed with the immobilized enzyme, the treatment efficiency increased with the immobilized pectinase dosage. When 8 g/L immobilized pectinase was added, the treatment time was shortened from 16 h to 4 h, the highest removal rate of CODCr was 74.1%, the cationic demand decreased 68.7%, and the electrical conductivity in the white water decreased 30.1%. The results indicated that the combination of predominant bacterial species and immobilized pectinase could greatly improve the treatment efficiency of white water.