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In order to reverse the trend of ecological deterioration and resolve the conflict between ecological conservation and economic development, it is necessary to evaluate the trends of ecosystem services (ESs) and unravel the relationship between ESs and environmental drivers and identify the priority areas for ESs. In this research, we used the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model to quantify the variation of four important ESs (water purification, water yield, soil conservation, and habitat quality) in the Dongting Lake Basin from 2000 to 2015. During the past 15 years, water yield was declined by 3.38% and soil conservation was increased by 1.45%. Water quality purification was deteriorated with the rise in phosphorus export (5.32%) and nitrogen export (4.09%). Meanwhile, habitat quality was decreased by 3.27%. Trade-offs occurred primarily among water yield and other ESs. Social-ecological drivers importance analysis found that water yield was primarily influenced by precipitation and temperature. By contrast, water purification and habitat quality were more affected by the distribution of land use and land cover (LULC). Soil conservation was closely related to precipitation and geographical factor. Based on the distribution of ESs and the intensity of human activities, we delineated priority areas for each ESs using the systematic conservation planning tool (Marxan). LULC shifted most dramatically in water yield reserves (6.49%) with a large amount of lands conversed to cropland (4.4%) and build-up land (0.27%), which further increased the risk of water scarcity, while LULC changed less in other ESs priority areas due to human activities. Our study helps develop conservation strategies within specific area cost-effectively and provides scientific support for future conservation program of ESs formulation and adjustment.

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.

Antibiotics and microplastics (MPs) inevitably coexist in natural waters, but their combined effect on aquatic organisms is still ambiguous. This study investigated the individual and combined toxicity of chloramphenicol (CAP) and micro-polystyrene (mPS) particles to Microcystis aeruginosa by physiological biomarkers, related gene expression, and molecular dynamics simulation. The results indicated that both individual and joint treatments threatened algal growth, while combined toxicity was higher than the former. Photosynthetic pigments and gene expression were inhibited by single CAP and mPS exposure, but CAP dominated and aggravated photosynthetic toxicity in combined exposure. Additionally, mPS damaged cell membranes and induced oxidative stress, which might further facilitate the entry of CAP into cells during co-exposure. The synergistic effect of CAP and mPS might be explained by the common photosynthetic toxicity target of CAP and mPS as well as oxidative stress. Furthermore, the molecular dynamics simulation revealed that CAP altered conformations of photosynthetic assembly protein YCF48 and SOD enzyme, and competed for functional sites of SOD, thus disturbing photosynthesis and antioxidant systems. These findings provide useful insights into the combined toxicity mechanism of antibiotics and MPs as well as highlight the importance of co-pollutant toxicity in the aquatic environment.

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.

Although microplastics are emerging marine pollutants that have recently attracted increasing attention, it is still difficult to identify their sources. This study reviewed 6487 articles to determine current research trends and found 237 effective concentration points after sorting, which were distributed in four regions and related to freshwater ecosystems. Results found that 15 environmental variables represented natural and anthropogenic environmental characteristics, of which seven environmental variables were selected for experimental modelling. Random forest models fitted sample data, thus facilitating the identification of regional microplastics distribution. The global random forest model had random forest importance scores (RFISs) for gross domestic product, population, and the proportion of agricultural land use were 15.76 %, 15.64 %, and 14.74 %, respectively; these indicate that human activities significantly affected the global distribution of microplastics. In Asia, agriculture and urban activities are the main sources of microplastics, with an RFIS of 11.58 % and 12.24 % for the proportion of agricultural and urban land use, respectively. Activities in urban areas were determined to be the main influencing factors in North America, with an RFIS of 13.92 % for the proportion of urban land use. Agricultural activities were the main influencing factors in Europe, with RFISs for the proportion of agricultural land use of 16.90 %. Our results indicate that region-specific policies are required to control microplastics in different regions, with soil composition being a latency factor that affects microplastics' distribution.

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.

Purpose: To compare the quality of life of senior first-year students with normal vision and myopia, and to explore the risk factors related to quality of life in students with myopia. Methods: In this study, 1103 senior first-year students were enrolled in ten high schools. These students were divided according to the diopter degree, with 916 myopia students and 187 normal vision students. Visual function indexes, such as naked eye vision, were measured and recorded, and social demographic indexes and the National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) was used. The differences in quality of life between the two groups were compared. Multiple linear regression analysis was used to explore the possible risk factors for quality of life in myopia students. Results: In the NEI VFQ-25, the total quality of life scores of myopia students (77.06 ± 15.66) were lower than those of normal vision students (85.49 ± 12.37). The difference was statistically significant ( p = 0.007). In the correlation analysis, the total scores of quality of life in myopia students were positively correlated with wearing glasses ( p = 0.049), and were negatively correlated with study time ( p = 0.029). Multiple linear regression analysis showed that study time, wearing glasses and age were risk factors affecting quality of life in myopia students. Conclusion: Our results show that senior first-year myopia students have lower quality of life scores than students with normal vision. Study time, wearing glasses and age are risk factors for quality of life in senior first-year myopia students.

Water scarcity and quality deterioration often occur in economically developing regions, particularly during crises related to climate change or increasing human activities. The assignment of priority areas is considered a suitable strategy for stakeholders to mitigate water crises and cope with water stress. However, most studies focused on protecting water bodies in priority areas and did not consider the hydrological/hydrochemical/hydroecological interaction between aquatic and terrestrial ecosystems. We divided a watershed into manageable areas to select priority areas for multiple water-related ecosystem services (WES-priority areas), considering the aquatic-terrestrial interactions to predict the effects of climate change and human activities. The proposed novelty framework couples the soil and water assessment tool and maximum entropy models with a systematic conservation planning tool. It uses the gross domestic product as the economic cost to assess dynamic changes and social-environmental driving forces. A case study is conducted in the Xiangjiang River basin, a modified watershed of the main tributary of the Yangtze River, China. Results revealed that most of the WES-priority areas were located in the southern and southeastern regions of the upper reaches in all climatic scenarios. The conservation efficiency of the WES-priority areas decreased from 1.264 to 0.867 in 50 years, indicating that the level of protection declined as climate change accelerated. The precipitation was positively correlated with the WES-priority area selection in all climate scenarios. The temperature was only negatively correlated with the WES-priority areas when it exceeded 20 °C, and this effect became more pronounced as the temperature increased. The topographic factors had the most crucial impacts on the upstream priority areas selection. The water flow regulation service played a leading role in identifying WES-priority areas in the middle reaches because the priority areas' distribution here was closely related to the water yield, and its proportion decreased with the acceleration of global warming. The number of WES-priority areas was relatively low in the lower reaches. It was positively associated with the gross domestic product and the amount of built-up land. The proposed framework for WES-priority areas identification enables a sound trade-off between environmental protection and economic development.

High-strength, low-alloy (HSLA) steel has attracted much attention in the manufacturing industry because of its good combination of high strength and toughness, low cost, and good formability. Wire and arc additive manufacturing (WAAM) technology can realize the rapid prototyping of HSLA steel parts. This study investigated a 26-layer HSLA steel component fabricated with the WAAM technique. The microstructure of the deposited wall of ER120S-G is mainly acicular ferrite, and there are longitudinal, preferentially growing dendrites along the deposition direction. With the deposition height accumulation, the top sample’s interlayer temperature increases and the amount of acicular ferrite in the microstructure decreases, while the amount of quasi-polygonal ferrite, Widmanstatten ferrite increases. The changes in microhardness were consistent with the corresponding microstructure gradients: the microhardness of the top sample showed a decreasing trend along the deposition direction, while the microhardness of the middle sample was uniform and stable. The present work shows that the mechanical properties of HSLA steel parts deposited using WAAM technology have good strength and toughness. The microstructure gradient of the sample along the deposition direction did not lead to a significant difference in the tensile strength of the sample at different heights. On the contrary, the ductility of the longitudinal sample is slightly lower than that of the transverse sample, indicating some anisotropy in the deposited sample, which is related to the directional growth of grains along the direction of heat flow. From the current work, the thin wall of HSLA steel prepared with the WAAM process has good mechanical properties, which indicates that it is feasible to replace the traditional processing method with the WAAM process to rapidly manufacture an HSLA steel structure meeting the performance requirements.

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.

Hydrology-climate changes and food availability are expected to be the primary drivers that result in a loss of waterbirds diversity. Non-biological factors are vital to food availability in interconnected river-lake systems, so in addition to identifying the ecological response to drivers, it is also important to analyze and quantify relationships between drivers. In order to explore the impacts of these drivers on the wintering waterbirds, we selected Dongting Lake (DTL) as a study area, which is a typical interconnected river-lake system in the middle and lower reaches of the Yangtze River Floodplain. The Anatidae species, most of which are herbivorous, were chosen as the representative waterfowl. The Pearson correlation coefficient was applied to select variables related to the timing of water recession and food availability, which have significant influences on the Anatidae. Then, the structural equation model (SEM) was carried out to quantify the relationships among the food availability, hydrological variables, and climatic variables. The results showed that unseasonably early or late water recession had a negative impact on the diversity of the Anatidae, and in particular affected population dynamics of the Lesser White-fronted goose Anser erythropus. Significant changes in Anatidae populations in DTL occurred in response to maximum NDVI (r = 0.53, p0.01) and the interval time of water recession (r = -0.43, p0.1). Water level, flow, and interval time of water recession explained 71% of maximum NDVI in DTL. In addition, hydraulic interactions between the mainstream and each lake jointly affected the inundation pattern and the vegetation growth stage of the lake after the flood season, thus affecting foraging suitability. Our findings suggest that water compensation should be carried out within an appropriate range of hydraulic gradient to optimize the time of water recession and improve the suitability of the habitat effectively.

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.

Two scandium coordination polymers (Sc-CPs), [Sc(L1)2(DMF)] (DMF = N,N′-dimethyl formamide, H2L1 = pyrazine-2,3-dicarboxylic acid) (1) and [Sc(L2)(C2O4)0.5(H2O)2]·H2O (H2L2 = pyrazine-2,5-dicarboxylic acid) (2), were prepared via hydrothermal and microwave (MW) heating techniques. It is noted that MW heating can effectively accelerate the reaction compared with a conventional hydrothermal method and decrease the crystal size of the samples. 1 shows a 1D non-planar double chain, while 2 exhibits a brick-like 2D network. After activation, 1 and 2 exhibit good catalytic performance for the cyanosilylation reaction of aromatic aldehydes; in addition, the catalysts prepared by the MW method exhibit better catalytic activity compared with those synthesized by the conventional hydrothermal method.

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

In our previous work, a family of isostructural lanthanide metal-organic frameworks, [Ln3(L)3(H2O)2]·(H3O)3·(H2O)4·(DMF)3 (abbreviated as Ln3(L)3(H2O)2, Ln = Eu, Tb, Sm, Dy and Gd) were synthesized under solvothermal conditions based on a semi-rigid tetravalent carboxylic tetracarboxylic acid (3,3′,5,5′-biphenyltetracarboxylic acid, H4L). Due to the good sensitization of the H4L ligand, Ln3(L)3(H2O)2 all show the intense characteristic emission bands of the corresponding lanthanide ions. The optical properties of Ln3(L)3(H2O)2 can be easily tuned by doping different lanthanide ions into the same host frameworks. Moreover, white-light emission can be successfully realized for four kinds of codoped compounds Tb0.005Eu0.005Gd0.990L, Dy0.006Eu0.006Gd0.988L, Dy0.0002Sm0.001Gd0.9988L and Tb0.002Sm0.006Gd0.992L (the value refer to the starting molar ratios of Ln3+ ions).

Background Fungal keratitis is one of the major causes of visual impairment worldwide. However, the effectiveness of corneal collagen cross-linking (CXL) for fungal keratitis remains controversial. In this study, we developed an in vitro and an in vivo models to assess the efficacy of CXL for Fusarium keratitis. Methods The effect of in vitro CXL fungicidal was evaluated on the cultures of Fusarium solani which were exposed to irradiation for different durations. Viability of fungal was appraised under four conditions: no treatment (control); CXL: UVA (365 nm)/riboflavin; riboflavin and UVA (365 nm). Each batch of sterile plate culture was irradiated for different CXL durations. The in vivo Therapeutic effect was studied on a mouse keratitis model. The animals were divided randomly into three groups: group A with no treatment (control); Group B with CXL treatment for two minutes and group C with CXL treatment for three minutes. The CXL procedure was performed 24 h post inoculation in each group. All mice with corneal involvement were scored daily for 7 days and 10 days after infection. Corneals were extracted at various time points for quantitative fungal recovery. Histological evaluations were conducted to calculate the number of polymorphonuclear cells. Results Viability of fungal decreased significantly in CXL group with 30-min irradiation compared with that in control, riboflavin and UVA groups (P

There is a growing recognition of the broader environmental significance of exploring the relative importance of climate change and anthropogenic impacts on hydrologic fluctuations in river-lake systems. In the case of Dongting Lake, the typical river-lake system, we collected the water level from 1990 to 2019, spanning before and after the operation of the Three Gorges Dam (TGD) in 2003. This study was conducted to detect water level fluctuations in Dongting Lake and to quantify the relative influence of climate, land cover and dam construction on water levels. We defined the impact of the dam construction as the three inlets inflow of Yangtze River (In-YR), and four waters inflow of Hunan (In-HN). The Mann-Kendall (M-K) test revealed the trends and change points of water level fluctuations. Structural Equation Model (SEM) was used to detect the direct and indirect effects of these factors on water level and quantify their relative importance. The MIKE21 hydrodynamic model reflected the spatial-temporal variability of water levels under the action of key driver. The results showed that the water level appeared a downward trend during 1990-2019 and the change point appeared in 2003; During 1990-2002, the significant factors were: precipitation (V = 0.469, P = 0.013), evaporation (V = -0.424, P = 0.029), non-agricultural cover (V = -0.334, P = 0.025), and agricultural cover (V = 0.235, P = 0.033); During 2003-2019, the significant factors were: In-YR (V = 0.436, P = 0.007), In-HN (V = 0.431, P = 0.012), and precipitation (V = 0.349, P = 0.045); The In-YR was the key factor affecting the changes of the water level during 1990-2019; Under the influence of In-YR, the most obvious fluctuation of water level was in the flood adjustment period (Jun-Aug) and the impoundment period (Sep-Nov) when the average declined by about 0.50 and 0.67 m, respectively. Our findings provide a new insight into how to better maintain the stability of river-water system water resources under the influence of multiple factors.

Recently, layered bismuth oxyhalides (BiOX) have been a well-deserved hotspot in the field of photocatalysis owning to their fascinating physicochemical properties derived from unique layered structures. Nevertheless, insufficient sunlight absorption, rapid recombination of electron-hole (e--h+) pairs, finite carrier concentration, and weak interaction between BiOX surface and reactant molecules inevitably limit the photocatalytic performance of BiOX. Given this, vacancy engineering, which can unleash the great potential to manipulate crystal and electronic structures and surface chemistry of BiOX, is widely applied to improve BiOX to meet the increasingly diverse theoretical and applicable needs. In this review, we focus on recent development in the design of appropriate vacancies on the BiOX for photocatalytic application. The introduction and analysis of popular vacancies creating approaches for BiOX and techniques to distinguish various vacancies are provided. The inherent functionality of BiOX vacancies in photocatalysis at the molecular level is clarified. Then we present representative photocatalytic applications, performance, and corresponding vacancy behavior of vacancy-mediated BiOX. Finally, based on an unambiguous understanding of the vacancy–property relationships and a complete view of the state of the art of vacancy-mediated BiOX, the future directions and possibilities for the rational design of vacancies to acquire ideal properties are explored.

Climate changes are related to the changes in the distribution of migratory species, which irreparably harm biodiversity. In this study, we evaluated the habitat change and population centroid shift for 7 orders and 23 different species on the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List of migratory birds from 2014 to 2017 in current to mid-21st (2041–2700) century by Maximum Entropy method (MaxEnt) model. We found that there is significant spatial variability in geographical suitability, with the Yangtze River basin losing 9.74% of suitable habitat and the Pearl River basin losing 13% of habitat. The area of suitable habitat decreases over 3% of total habitat area in China under the RCP 2.6, and decreases about 10% of total habitat area in China under RCP 8.5 scenario, with the population centroid of habitat moving about 50 km to northeast on average. Furthermore, the mean suitability of migratory birds will decrease over 3% in the future, which means environmental variables are changing in directions that are not suitable for birds. Migratory birds will change their habitat and growth cycle in response to the climate change. The direction and distance of the population centroid are different for every species. Most of the individual species in the study will move over 50 km and all the species will move to places with higher suitability. For the whole of China, the constraint for migratory birds is t min (Minimum temperature). The dominant variable in southeast China is NDVI (Normalized Difference Vegetation Index), while alt (altitude) in the north China. The decline in the suitable habitat area and shift in the population centroid will lead to the changes in the time and distance of the migration process, resulting in more adverse conditions for the survival of migratory birds. Our study proves the adverse role of climate change in species distribution which is a prerequisite for protecting species in the future.

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.

A new three-dimensional manganese-based metal–organic framework Mn4L2(HL)(H2O)5, (1), based on semi-rigid 5-((4′-(tetrazol-5′’-yl)benzyl)oxy)isophthalic acid ligand (H3L) have been prepared and characterized under solvothermal condition. In the structure of 1, trinuclear Mn3O13N2 units are linked each other by sharing vertex and edge to form left- and right- hand helical O-Mn-O chains along b axis, then adjacent left and right handed helical chains are interconnected by L3− and HL2− ligands to generate a 2D layer and L3− ligands with mode II connect the neighboring layers to form a 3D network. 1 shows high stability under different pH conditions and various organic solvents. After activation, 1 exhibits excellent catalytic properties for two typical C C bond reactions, cyanosilylation and Knoevenagel condensation reaction of aldehydes, under solvent-free conditions at room temperature.

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.

Two new three-dimensional (3D) Sc(III)-based metal organic frameworks (MOFs) [Sc2(OH)2(TDC)2]·4H2O (1) and [Sc3O(fum)3(H2O)3(NO3)]·DMF (2) (H2TDC = 2,5-thiophenedicarboxylic acid, H2fum = fumaric acid) have been hydrothermally synthesized. For 1, TDC2− ligands connect infinite one-dimensional (1D) -Sc-OH-Sc-OH- chains to form open-framework with rhombic channels along the a axis. In 2, flexible fum2− ligands link adjacent trimer [Sc3O(COO)6(H2O)3] secondary building units showing hexagonal-closed circular pores with a diameter of approximate 9.9 A. Furthermore, the desolvated material la can retain the framework, presenting good catalytic activity, significant universality and substrate-selectivity for Strecker-type reactions of trimethylsilyl cyanide (TMSCN) and various aromatic aldimines, especially for N-benzyl 4-methoxybenzaldimine.

The vibration of the oil-tank can reflect the mechanical condition of transformer internal windings and cores. Although there were several studies about the vibration of the transformer, most of them do not take into account the inherent connection between different measuring points, which results in insufficient utilization of vibration information. To conquer this shortcoming, a fault diagnosis method for transformer winding looseness based on vibration sensor array is proposed. An array measurement system was set up, and a suitable measurement method was put forward. Because the voltage fluctuation of the transformer in actual operation is very small while the load current fluctuates greatly and the winding vibration is mainly influenced by the current. Load tests were conducted on a single-phase transformer. The influence of the current on the vibration characteristics was studied. Different levels of winding looseness were set up and their vibration characteristics were studied. The matrix distance was used to judge the deviation of the array signal. The results show that the array signal does not change with the current change. When the windings are loosened, the array distance of the array signal increases significantly. It provides a new idea for the diagnosis of the mechanical fault of transformer windings based on vibration signals.

Three scandium metal-organic frameworks (Sc-MOFs), [Sc(pydc)(Hpydc)(H2O)]·H2O (1), [Sc2(pydc)3(H2O)4]·5H2O (2) and [Sc(pydc)(H2O)(NO3)] (3) with similar Sc2(pydc)2 building unit were prepared by using 2,3-pyridinedicarboxylic acid (H2pydc) ligand under hydrothermal conditions. Compound 1 exhibits a ladder-shaped chain with Sc2(pydc)2 units, which further construct a supramolecular characteristic with water molecules via hydrogen bond. Compound 2 features a waved layer made up of pydc(2-) ligands and two types of crystallographically different Sc(III) ions, among which Sc2 and pydc(2-) ligands constructed the Sc2(pydc)2 units. In compound 3, left and right helixes were alternately linked by the Sc2(pydc)2 units forming a hexagonal network with nbo-a topology. All the prepared compounds present effective heterogeneous Lewis acid catalytic functionality for the cyanosilylation of aldehyde.

Three scandium metal-organic frameworks (Sc-MOFs), [Sc(pydc)(Hpydc)(H2O)]·H2O (1), [Sc2(pydc)3(H2O)4]·5H2O (2) and [Sc(pydc)(H2O)(NO3)] (3) with similar Sc2(pydc)2 building unit were prepared by using 2,3-pyridinedicarboxylic acid (H2pydc) ligand under hydrothermal conditions. Compound 1 exhibits a ladder-shaped chain with Sc2(pydc)2 units, which further construct a supramolecular characteristic with water molecules via hydrogen bond. Compound 2 features a waved layer made up of pydc(2-) ligands and two types of crystallographically different Sc(III) ions, among which Sc2 and pydc(2-) ligands constructed the Sc2(pydc)2 units. In compound 3, left and right helixes were alternately linked by the Sc2(pydc)2 units forming a hexagonal network with nbo-a topology. All the prepared compounds present effective heterogeneous Lewis acid catalytic functionality for the cyanosilylation of aldehyde.