32 research outputs found

    NAQPMS-PDAF v2.0: A Novel Hybrid Nonlinear Data Assimilation System for Improved Simulation of PM2.5 Chemical Components

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    PM2.5, a complex mixture with diverse chemical components, exerts significant impacts on the environment, human health, and climate change. However, precisely describing spatiotemporal variations of PM2.5 chemical components remains a difficulty. In our earlier work, we developed an aerosol extinction coefficient data assimilation (DA) system (NAQPMS-PDAF v1.0) that is suboptimal for chemical components. This paper introduces a novel hybrid nonlinear chemical DA system (NAQPMS-PDAF v2.0) to accurately interpret key chemical components (SO42-, NO3-, NH4+, OC, and EC). NAQPMS-PDAF v2.0 improves upon v1.0 by effectively handing and balancing stability and nonlinearity in chemical DA, which is achieved by incorporating the non-Gaussian-distribution ensemble perturbation and hybrid Localized Kalman-Nonlinear Ensemble Transform Filter with an adaptive forgetting factor for the first time. The dependence tests demonstrate that NAQPMS-PDAF v2.0 provides excellent DA results with a minimal ensemble size of 10, surpassing previous reports and v1.0. A one-month DA experiment shows that the analysis field generated by NAQPMS-PDAF v2.0 is in good agreement with observations, especially reducing the underestimation of NH4+ and NO3- and the overestimation of SO42-, OC, and EC. In particular, the CORR values for NO3-, OC, and EC are above 0.96, and R2 values are above 0.93. NAQPMS-PDAF v2.0 also demonstrates superior spatiotemporal interpretation, with most DA sites showing improvements of over 50 %–200 % in CORR and over 50 %–90 % in RMSE for the five chemical components. Compared to the poor performance in global reanalysis dataset (CORR: 0.42–0.55, RMSE: 4.51–12.27 µg/m3) and NAQPMS-PDAF v1.0 (CORR: 0.35–0.98, RMSE: 2.46–15.50 µg/m3), NAQPMS-PDAF v2.0 has the highest CORR of 0.86–0.99 and the lowest RMSE of 0.14–3.18 µg/m3. The uncertainties in ensemble DA are also examined, further highlighting the potential of NAQPMS-PDAF v2.0 for advancing aerosol chemical component studies

    3% diquafosol sodium eye drops in Chinese patients with dry eye: a phase IV study

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    IntroductionThe efficacy and safety of 3% diquafosol sodium eye drops in Chinese patients with dry eye in the real-world setting remains unclear.Methods3099 patients with dry eye symptoms were screened according to Asia Dry Eye Society latest recommendation. Among them, 3000 patients were enrolled for a phase IV study. We followed up with multiple clinical characteristics including corneal fluorescein staining, tear break up time, Schirmer’s tests, visual acuity, intraocular pressure, and others. The follow ups were performed at baseline, 2 weeks and 4 weeks after treatment.ResultsBased on the results of corneal fluorescein staining and tear break up time, all age and gender subgroups exhibited obvious alleviation of the symptoms among the patients with dry eye, and the data in elderly group showed the most significant alleviation. All the adverse drug reactions (ADRs, 6.17%) were recorded, among which 6% local ocular ADRs were included. Meanwhile, mild ADRs (91.8%) accounted for the most. Most of the ADRs (89.75%) got a quick and full recovery, with an average time at 15.6 days. 1.37% of patients dropped out of the study due to ADRs.DiscussionThe use of 3% diquafosol sodium eye drop is effective and safe in the treatment of dry eye, with a low incidence of ADRs showing mild symptoms. This trial was registered at Chinese Clinical Trial Registry ID: ChiCTR1900021999 (Registration Date: 19/03/2019)

    Application Prospect and Preliminary Exploration of GelMA in Corneal Stroma Regeneration

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    Corneal regeneration has become a prominent study area in recent decades. Because the corneal stroma contributes about 90% of the corneal thickness in the corneal structure, corneal stromal regeneration is critical for the treatment of cornea disease. Numerous materials, including deacetylated chitosan, hydrophilic gel, collagen, gelatin methacrylate (GelMA), serine protein, glycerol sebacate, and decellularized extracellular matrix, have been explored for keratocytes regeneration. GelMA is one of the most prominent materials, which is becoming more and more popular because of its outstanding three-dimensional scaffold structure, strong mechanics, good optical transmittance, and biocompatibility. This review discussed recent research on corneal stroma regeneration materials and related GelMA

    Quantifying the Spatio-Temporal Variations and Impacts of Factors on Vegetation Water Use Efficiency Using STL Decomposition and Geodetector Method

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    Water use efficiency of vegetation (WUE), the ratio of carbon gain to water loss, is a valid indicator to describe the photosynthetic carbon–water coupling relationship. Understanding how and why WUE changes are essential for regional ecological conservation. However, the impacts of various factors and their interactions on the spatial variation of WUE remain uncertain in the arid land of Northwest China. Here, we selected the Qilian Mountains (QM) and Hexi Corridor (HC) as the study areas. Supported by the Google Earth Engine, we explored the spatio-temporal variations of WUE in QM and HC for 2002–2021 using STL decomposition (a seasonal-trend decomposition procedure), trend analysis, and the Hurst index. Then, the Geodetector method was applied to quantify impacts of geographical and eco-meteorological factors on the spatial variation of WUE. The WUE in HC was higher than that in QM. Interestingly, the opposite longitude zonality characteristics are shown in the QM and HC. In QM, the WUE showed an upward trend with longitude increasing, while a downward trend with longitude increasing in the oases of HC. The WUE of cropland was the highest (1.15 ± 0.35 gC kg−1 H2O), and that of alpine vegetation was the lowest (0.2 ± 0.15 gC kg−1 H2O). WUE showed a decreasing trend across the study area, almost certainly due to a drop from May to July during 2002–2021. The air temperature is the dominant factor influencing the spatial variation of WUE. In addition, the interaction of any two factors is greater than the independent influence of either factor alone. The Geodetector method proved to be effective for quantifying the impact of complex multi-factors on the spatial variation of WUE. This study provides a new technical scheme to analyze the spatio-temporal pattern and quantify the impact of multi-factors on the spatial variation of WUE. These findings aid in understanding underlying mechanisms of WUE variation and thereby will be beneficial for clarifying the response of vegetation to climate change

    Availability of benzathine penicillin G for syphilis treatment in Shandong Province, Eastern China

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    Abstract Background The shortage of benzathine penicillin G (BPG) worldwide presents a major challenge in the treatment of syphilis. Its availability for syphilis treatment has not been adequately evaluated in China. Methods Two surveys were conducted among hospitals providing sexually transmitted infection clinical services in Shandong Province in 2012 and 2018. Data on the basic information and BPG availability of the surveyed hospitals and related factors were collected and analyzed using SPSS 17.0. Results A total of 433 and 515 hospitals were surveyed in 2012 and 2018, respectively. A significant difference in BPG availability was observed among different levels and types of hospitals both in 2012 (X2 = 9.747, p = 0.008; X2 = 37.167, p = 0.000) and 2018 (X2 = 11.775, p = 0.003; X2 = 28.331, p = 0.000). The BPG availability among surveyed hospitals increased from 45.0% in 2012 to 56.4% in 2018 (X2 = 11.131, p = 0.001). The BPG availability was higher in 2018 than in 2012 among county-level hospitals (52.0% vs. 40.8%, X2 = 7.783, p = 0.005), general western medicine hospitals (62.1% vs. 50.0%, X2 = 6.742, p = 0.009), maternal and child health hospitals (57.1% vs. 26.9%, X2 = 13.906, p = 0.000), and public hospitals (56.8% vs. 45.0%, X2 = 11.361, p = 0.001). However, the county-level availability of BPG (at least one hospital has BPG in a county-level unit) has not improved between 2012 and 2018 (65.93% vs. 70.34%; X2 = 0.563, p = 0.453). The absences of clinical needs, restriction of clinical antibacterial drugs, and lack of qualifications for providing syphilis treatment were the major reasons for the low BPG availability of hospitals. Conclusions BPG availability for syphilis treatment in Shandong Province remains low and presents disparities among different levels and types of hospitals, although it has been improved in recent years. The low availability of BPG for syphilis treatment in China is related to its clinical use by doctors rather than the market supply. Health care reforms should further improve the availability and accessibility of health services

    A Semantic++ MapReduce Parallel Programming Model

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    Data from: Contrasting effects of ectomycorrhizal and arbuscular mycorrhizal tropical tree species on soil nitrogen cycling: the potential mechanisms and corresponding adaptive strategies

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    While it is increasingly recognized that ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) tree species vary in their effects on soil nitrogen (N) cycling, little is known about the mechanisms causing and how ECM and AM trees adapt to this variation. Using monoculture plots of six ECM and eight AM tropical trees planted in a common garden, we examined whether the contrasting effects of ECM and AM trees on soil N cycling could be explained by their differences in plant traits. Furthermore, rhizosphere effects on soil N transformations and soil exploration by fine roots were also measured to assess whether ECM and AM trees differed in N acquisition capacities. Results showed that soil NH 4+N concentration, net N mineralization and net nitrification rates were markedly lower, but soil C:N ratio was significantly higher beneath ECM trees than beneath AM trees. This more closed N cycling caused by ECM trees was attributed to their resource-conservative traits, especially the poorer leaf litter decomposability compared with AM trees. To adapt to their induced lower soil N availability, ECM trees were found to have greater rhizosphere effects on NO 3-N concentration, net N mineralization and net nitrification rates to mine N, and higher soil exploration in terms of root length density to scavenge N from soils, indicating that these two strategies work in synergy to meet N demand of ECM trees. These findings suggest that ECM and AM trees have contrasting effects on soil N cycling owing to their differences in leaf litter decomposability and correspondingly possess different N acquisition capacities

    Risk Factors of Urrets-Zavalia Syndrome after Penetrating Keratoplasty

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    Objective: The objective of this study was to analyze the clinical features and risk factors of Urrets-Zavalia syndrome (UZS) after penetrating keratoplasty (PKP). Methods: The medical records of 152 patients who underwent PKP at the Department of Ophthalmology, Tongji Hospital, between January 2014 and December 2016 were retrospectively reviewed. UZS was diagnosed based on pre- and post-operative pupillary findings. The relationships among the primary disease, postoperative intraocular pressure (IOP), and the incidence of UZS were statistically analyzed. The pupillary changes during the follow-up period were studied. Results: Among the 152 included patients, 23 were diagnosed with UZS, with an incidence of 15.13%. The primary diseases of the UZS patients were keratoconus (eight cases, 34.78%), viral keratitis (six cases, 26.08%), leukoma (four cases, 17.39%), fungal corneal ulcer (two cases, 8.70%), corneal endothelial decompensation (two cases, 8.70%), and corneal degeneration (one case, 4.35%). The incidence of UZS in keratoconus patients was higher than that in patients with fungal corneal ulcer (42.11% versus 6.25%, p = 0.003); In addition, the transient postoperative high IOP was not significantly related to the incidence of UZS in keratoconus patients in our study (p = 0.319). Twenty-one patients with UZS were followed up for >6 months, seven of whom (33.33%) recovered spontaneously (within the range of 48 days to 1.5 years). Conclusion: In our study, the incidence of UZS after PKP was 15.13%, and 33.33% of these patients recovered spontaneously. UZS may be more likely to occur in patients with keratoconus. Postoperative transient high IOP may increase the incidence of UZS after PKP for keratoconus
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