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Wetlands are important environmental resources that are vulnerable to droughts and floods. Studying drought-flood events and their driving factors is essential for wetland resource planning and management. However, climate change and human activities present dynamic challenges that traditional approaches are unable to simulate dynamically in a rapidly changing environment. This makes quantitative analysis difficult. Our research focused on the innovative use of the data stream model, namely online bagging of Hoeffding adaptive trees, to quantify drought and flood drivers in response to climate change and human activity. The proposed approach was applied to a river-lake system, the Dongting Lake wetland. The frequency and duration characteristics of drought-flood events were analyzed. In addition, the cyclical changes of droughts and floods were analyzed by wavelet analysis. Then, drought-flood indicators as well as climatic and hydrological factors were entered into a dynamic data stream model for quantitative calculations. The results showed that the water conservancy projects largely reduced flood events while aggravating droughts. The frequency of floods decreased by 4.91% and the frequency of droughts increased by 6.81% following the construction of the Gezhouba Hydro-project and the Three Gorges Dam. Precipitation and Sankou streamflow were two dominant factors in the Dongting Lake drought and flood events, both of which had a feature importance value of approximately 0.3. This research showed how the data stream model can be used in a changing environment and the applicability of the conclusions reached through real-world instances. Moreover, these quantitative outputs can help in the sustainable utilization of Dongting Lake wetland resources.

The energy-absorption mechanism of nanofluidic systems is being investigated under dynamic cases, represented by the split Hopkinson pressure bar experiment. However, the cost of this cannot be ignored. Therefore, numerical simulation is playing an increasingly important role in optimizing the split Hopkinson pressure bar experimental technology and analyzing its accuracy. In this paper, a three-dimensional finite element simulation model of the split Hopkinson pressure bar experimental devices was proposed to analyze the energy-absorption capabilities of nanofluidic-system-filled tubes. The reliability of this methodology was discussed in terms of model construction, model validation and potential application, indicating the simulation methodology is applicable to further investigation and can provide a reference for engineering practice. The simulation results showed that the infiltration pressure and the mass ratio of solid to liquid determine the post-buckling compression stress and the effective compression stroke, respectively.

Natural inorganic colloids (NICs) are the most common and dominant existence in the ecosystem, with high concentration and wide variety. In spite of the low toxicity, they can alter activity and mobility of hazardous engineered nanoparticles (ENPs) through different interactions, which warrants the necessity to understand and predict the fate and transport of NICs in aquatic ecosystems. Here, this review summarized NICs properties and behaviors, interaction mechanisms and environmental factors at the first time. Various representative NICs and their physicochemical properties were introduced across the board. Then, the aggregation and sedimentation behaviors were discussed systematically, mainly concerning the heteroaggregation between NICs and ENPs. To speculate their fate and elucidate the corresponding mechanisms, the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) and extended DLVO (X-DLVO) theories were focused. Furthermore, a range of intrinsic and extrinsic factors was presented in different perspective. Last but not the least, this paper pointed out theoretical and analytical gaps in current researches, and put forward suggestions for further research, aiming to provide a more comprehensive and original perspective in the fields of natural occurring colloids.

Background: Immunologic graft rejection is the main complication of corneal transplants. This study aimed to investigate the effect of melatonin (MT) on the rejection of corneal transplantation.Methods: Corneal allografts were performed by grafting corneas from BALB/C mice to C57BL/6 hosts. MT (50 mg/kg) was intraperitoneally injected into the hosts every day from the day of transplantation. The survival of grafts was observed by slit lamp biomicroscopy, and inflammatory cell infiltration was detected by hematoxylin and eosin staining and immunohistochemistry. The balance of Teff and Treg immune cells in draining lymph nodes (DLNs) was detected by flow cytometry. The levels of cytokines related to the grafts and DLNs were detected using real-time fluorescence quantitative PCR. Additionally, we used the mouse macrophage line RAW264.7 to study the effect of MT on the activation of NLRP3 inflammatory body.Results: MT treatment improved the graft survival rate, reduced inflammatory cell infiltration in the graft, decreased the percentage of Th1/Th17 cells in the DLNs, and increased the percentage of Treg cells. Melatonin inhibited the activation of the NLRP3 inflammasome, thereby reducing the expression of IL-1β and other related proinflammatory cytokines such as MCP-1, MIP-1, NLRP3, ASC, TNF-a and VEGF-A (all p < 0.05).Conclusion: Our study demonstrates that MT promotes the survival of mouse corneal grafts by inhibiting NLRP3-mediated immune regulation, reducing immune cell activation and cell migration, and inhibiting the production of inflammatory-related cytokines. Treatment with MT might provide a potential clinical therapeutic target for corneal transplantation.

Micro- and nano-plastics are common emerging pollutants of great interest. However, the impacts of them on terrestrial plants were still poorly understood. In this study, comparative effects of exposure of polystyrene nanoplastics (PS) and amino-modified polystyrene nanoplastics (PS-NH

Nanoplastics and carbon nanotubes (CNTs) is one of the emerging environmental contaminants and a widely used engineering nanomaterial, and their biological toxicity has been frequently studied. However, there has been no research on the combined exposure of these two totally different shape nanoparticles. To explore their potential threat to freshwater ecosystems, Microcystis aeruginosa (M. aeruginosa) was exposed to concentration gradients of polystyrene nanoplastics (Nano-PS) and multi-walled carbon nanotubes (MWCNTs). The physiological analysis and whole-transcriptome sequencing were integrated to certify the cytotoxicity. As the physiological results showed, the low concentration (5 mg/L) of these two nanoparticles showed a stimulation on the growth (6.49%–12.2%) and photosynthesis (0–7.6%), and the coexposure was slightly higher than individuals. However, other concentrations showed inhibitory effect, especially at high concentration (50 mg/L), and all physical signs and electron microscope images showed obvious cytotoxicity. Compared with the individuals, the coexposure showed an antagonistic effect induced by the heterogeneous agglomeration which decreased the surface toxicity and the contact with algae of nanomaterials. Transcriptome results showed that coexposure treatment had the fewest differential genes, and the primary effects embodied in the disturbances of cellular and metabolic processes which were superior to the individuals. In the 50 mg/L Nano-PS, the translation process was significantly disordered, and MWCNTs could disrupted the photosynthesis, multiple metabolism processes, membrane transport, and translation. These findings demonstrated the aquatic toxic mechanism from cellular and metabolic processes of Nano-PS and MWCNTs for M. aeruginosa and provided valuable data for environmental risk assessment of them.

The drivers that determine the hydrological connectivity (HC) are complex and interrelated, and disentangling this complexity will improve the administration of the river–lake interconnection system. Dongting Lake, as a typical river–lake interconnected system, is freely connected with the Yangtze River and their HC plays a major role in keeping the system healthy. Climate, hydrology, and anthropogenic activities are associated with the HC. In this study, hydrological drivers were divided into the total flow of three inlets (T-flow) and the total flow of four tributaries (F-flow). To elucidate the HC of the Dongting Lake, HC was calculated by geostatistical methods in association with Sentinel-2 remote sensing images. Then, the structural equation model (SEM) was used to quantify the impacts of hydrology (F-flow, and T-flow) and meteorology (precipitation, evaporation, and temperature) on HC. The geostatistical analysis results demonstrated that the HC showed apparent seasonal change. For East and West Dongting Lake, the dominant element was north–south hydrological connectivity (N–S HC), and the restricted was west–east hydrological connectivity (W-E HC), but the dominant element was E–W HC and the restricted was N–S HC in South Dongting Lake. The results of SEM showed that N–S HC was mainly explained by T-flow (r = 0.49, p < 0.001) and F-flow (r = 0.28, p < 0.05). T-flow, temperature (r = 0.33, p < 0.05), and F-flow explained E–W HC. The finding of this work supports the management of both the Dongting Lake floodplain and other similar river–lake floodplain systems.

The primitive biochar (BC) and NiFe2O4/biochar composites (NFBC), biological adsorbents prepared from vinasse wastes, possess the environmental application in levofloxacin (LEV) removal. In this study, the efficient adsorption of LEV onto biochar synthesized by pyrolysis of vinasse wastes from aqueous environment was investigated. The influencing factors (i.e., pH, reaction time, and temperature) of adsorption process were also well studied. The results indicated that the maximum adsorption capacities of both BC and NFBC were occurred in mildly acidic condition (pH 6). In addition, the biochar adsorption capacities were obviously increased in higher temperature (25–45 °C). The chemistry adsorption and monolayer homogeneous dominated adsorption process of LEV onto BC and NFBC. The adsorption process was spontaneous and endothermic by thermodynamic analysis. The SEDA (site energy distribution analysis) explained that the adsorption effectivity increased by increasing site energy of biochar surface. The SEDA revealed the more energy heterogeneity in NFBC, fitting the characterization result of Fourier-transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The electron-donor-acceptor (EDA) interactions and hydrogen bonds is suggested as the major adsorption mechanism. And as for the adsorption of the various biowaste recycled synthetic, this study can be referred in discussion of performance analysis and optimal condition.

Purpose The aim of this study was to investigate the differences in anxiety and depression between adolescents with myopia and those with normal vision and to examine the relationship between the level of anxiety and depression and the degree of myopia. Methods A total of 1,103 first‐year high school students aged 14–17 years were included in the study. The study group comprised 916 persons with myopia, while the control group comprised 187 persons without refractive error. Volunteers underwent routine eye examinations and completed a set of questionnaires about anxiety and depression. Then, the Self‐Rating Anxiety Scale (SAS) and Self‐Rating Depression Scale (SDS) scores were compared between groups, and the relationships between anxiety and the degree of myopia and between depression and the degree of myopia were analyzed. Results There was a significant difference in anxiety rate between the students with normal vision and those with myopia. The SAS scores among students with mild, moderate, and severe myopia were also significantly different. However, compared with the students with normal vision, the rate of depression was not significantly increased in the students with myopia, except in cases of severe myopia. Additionally, the SAS scores correlated closely with the diopters of the participants’ glasses (r = 0.43, p = .045), while the relationship between SDS scores and the diopters of glasses was not significant (r = 0.19, p = .325). Conclusion There was a correlation between myopia and mental health in adolescent students, especially in terms of anxiety., There was a correlation between myopia and psychological health in adolescent students, especially in terms of anxiety. And the SAS scores correlated closely with the diopters of the glasses (p

The scheduling efficiency of carrier-based aircrafts on flight deck is an important factor on improving the sortie rates of aircrafts. Based on the key process of the sortie of deck-based aircrafts, the main research directions in the field of the scheduling of carrier-based aircrafts are summarized, which are the path planning and collision detection of carrier-based aircrafts, the integrated scheduling method of carrier-based aircraft fleets, and the coordinated scheduling strategies of carrier-based aircrafts. Then, the researches of carrier-based aircrafts dispatch system are introduced. The progress and shortcomings of the existing research results were pointed out, also, the feasible development directions in the future are proposed, which provides a reference for the research on the scheduling of aircrafts on flight deck.

Sc-CP 1, 1A, 1B and 1C with controllable morphologies were successfully synthesized by the conventional hydrothermal method and microwave (MW) assisted hydrothermal method. 1 was macroscopic, 1A was nano sized, while 1B and 1C were micron sized. Sc-CP 1 showed two-dimensional (2D) layered structure which was constructed from the connections of left- and right-hand helical chains. Catalytic experiments showed the catalytic performances of Sc-CP 1, 1A, 1B and 1C for the cyanosilylation reaction of aromatic aldehydes were dependent on the morphologies of the particles. Flower-ball-like 1C featuring a high concentration of Lewis acidic Sc(III) sites on its exposed external surfaces showed better catalytic activity than others, the best constant rate of which was 6.4 ​× ​10−3 min−1.