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African swine fever virus (ASFV) is the causative agent of African swine fever, a highly contagious and usually fatal disease in pigs. The pathogenesis of ASFV infection has not been clearly elucidated. Here, we used single-cell RNA-sequencing technology to survey the transcriptomic landscape of ASFV-infected primary porcine alveolar macrophages. The temporal dynamic analysis of viral genes revealed increased expression of viral transmembrane genes. Molecular characteristics in the ASFV-exposed cells exhibited the activation of antiviral signaling pathways with increased expression levels of interferon-stimulated genes and inflammatory- and cytokine-related genes. By comparing infected cells with unexposed cells, we showed that the unfolded protein response (UPR) pathway was activated in low viral load cells, while the expression level of UPR-related genes in high viral load cells was less than that in unexposed cells. Cells infected with various viral loads showed signature transcriptomic changes at the median progression of infection. Within the infected cells, differential expression analysis and coregulated virus–host analysis both demonstrated that ASFV promoted metabolic pathways but inhibited interferon and UPR signaling, implying the regulation pathway of viral replication in host cells. Furthermore, our results revealed that the cell apoptosis pathway was activated upon ASFV infection. Mechanistically, the production of tumor necrosis factor alpha (TNF-α) induced by ASFV infection is necessary for cell apoptosis, highlighting the importance of TNF-α in ASFV pathogenesis. Collectively, the data provide insights into the comprehensive host responses and complex virus–host interactions during ASFV infection, which may instruct future research on antiviral strategies.

Land-use/land-cover change (LULCC) often results in degradation of natural wetlands and affects the dynamics of greenhouse gases (GHGs). However, the magnitude of changes in GHG emissions from wetlands undergoing various LULCC types remains unclear. We conducted a global meta-analysis with a database of 209 sites to examine the effects of LULCC types of constructed wetlands (CWs), croplands (CLs), aquaculture ponds (APs), drained wetlands (DWs), and pastures (PASs) on the variability in CO2 , CH4 , and N2 O emissions from the natural coastal wetlands, riparian wetlands, and peatlands. Our results showed that the natural wetlands were net sinks of atmospheric CO2 and net sources of CH4 and N2 O, exhibiting the capacity to mitigate greenhouse effects due to negative comprehensive global warming potentials (GWPs; -0.9 to -8.7 t CO2 -eq ha-1 year-1 ). Relative to the natural wetlands, all LULCC types (except CWs from coastal wetlands) decreased the net CO2 uptake by 69.7%-456.6%, due to a higher increase in ecosystem respiration relative to slight changes in gross primary production. The CWs and APs significantly increased the CH4 emissions compared to those of the coastal wetlands. All LULCC types associated with the riparian wetlands significantly decreased the CH4 emissions. When the peatlands were converted to the PASs, the CH4 emissions significantly increased. The CLs, as well as DWs from peatlands, significantly increased the N2 O emissions in the natural wetlands. As a result, all LULCC types (except PASs from riparian wetlands) led to remarkably higher GWPs by 65.4%-2,948.8%, compared to those of the natural wetlands. The variability in GHG fluxes with LULCC was mainly sensitive to changes in soil water content, water table, salinity, soil nitrogen content, soil pH, and bulk density. This study highlights the significant role of LULCC in increasing comprehensive GHG emissions from global natural wetlands, and our results are useful for improving future models and manipulative experiments.

Numerous studies have been conducted to investigate the potential effect of educational robots, but what appears to be missing is an up-to-date and thorough review of the learning effectiveness of educational robots and the various influencing factors. In this study, a meta-analysis was conducted to systematically synthesize studies’ findings on the effects of educational robots on students’ learning outcomes. After searching for randomized studies describing educational robots interventions to improve learning outcomes, 34 effect sizes described in 17 articles met the selection criteria. The results of our work evidence a moderate but significantly positive effect of educational robots on learning outcomes (g = 0.57, 95% CI [0.49, 0.65], p < 0.00001). Moreover, moderator analyses were conducted to investigate important factors relating to the variation of the impact, including educational level and assessment type. Based on the findings of this study, we provide researchers and practitioners with insights into what characteristics of educational robot interventions appear to benefit students’ learning outcomes and how pedagogical approaches can be applied in various educational settings to guide the design of future educational robot interventions.

Accurately identifying important areas of biodiversity is one of the key issues in ecology and biodiversity research, as well as an important basis for the delineation of the red line for ecologi-cal protection and territorial spatial planning. With China's typical plateau mountainous area (Yunnan Province) as a research case, we used the net primary productivity (NPP) quantitative index method, InVEST model and InVEST model focusing on topographic relief to identify biodiversity important areas. The results showed that NPP quantitative index method was not suitable for the plateau mountainous areas with obvious vertical zonal development. The identified area contained only 26.1% of the protected areas. The InVEST model had higher identification accuracy than the NPP quantitative index method in Yunnan Province. The identified area covered 49.4% of the protected natural areas. Fragmentation was obvious in northwest Yunnan. The InVEST model focusing on topographic relief improved the identification accuracy of important areas of biodiversity, including 71.7% of nature reserves. The deficiency of NPP quantitative index method in water area identification was made up and the fragmentation problem of InVEST model was solved. The area of biodiversity important areas was 119466.94 km精确识别生物多样性重要区是生态学和生物多样性研究的关键问题之一,也是生态保护红线划定和国土空间规划的重要基础。本研究以中国典型高原山区云南省为研究案例,分别用净初级生产力(NPP)定量指标法、InVEST模型和顾及地形起伏的InVEST模型识别研究区生物多样性重要区。结果表明: NPP定量指标法不适用于垂直地带性发育明显的高原山区,其识别区域仅包含自然保护地的26.1%;InVEST模型较NPP定量指标法在云南省具有较高的识别精度,识别区域包含自然保护地的49.4%,但在滇西北破碎化格局明显;顾及地形起伏的InVEST模型提高了生物多样性重要区的识别精度,包含71.7%的自然保护区,同时弥补了NPP定量指标法对水域识别的缺漏,解决了InVEST模型的破碎化问题;云南省生物多样性重要区面积达119466.94 km

Sediment loads by large rivers play a crucial role in determining the fate of estuarine and coastal ecosystems. From 2013 to 2017, this study investigated the dynamics of mudflats and marsh pioneering vegetation (Scirpus species) in the coastal wetland at downstream end of the Yangtze Estuary. The results showed that, even with the historically lowest scale of upstream sediment load, the mudflat accretion (increase in elevation) and vegetation expansion in the marsh frontier still occurred. In the different monitoring sites, the net increases in the mudflat elevation were 24.34–57.51 cm, and the area of the pioneering vegetation increased by 2.18–4.74 times over 5 years. During the 2016–2017 period, with higher water discharges, the rates of mudflat accretion and vegetation colonization were much higher than those in former years. It was declared that a single-year high water discharge could trigger an intensive increase in sediment transport to the coastal region. Relative to water discharge, the year-to-year sediment load recorded upstream (Datong hydrographical gauging station) might not be a suitable indicator to interpret the mudflat and vegetation dynamics in the Yangtze Delta due to the high uncertainty of sediment loading processes along the transportation path. The recent monitoring indicated that positive interaction between vegetation establishment and sedimentary processes probably contribute to a continuous mudflat accretion and vegetation expansion in the mudflat frontier. We also suggest that a short-term substantial impulse in river and sediment discharge highly stimulated the accretion of coastal mudflat and the consequent expansion of marsh vegetation in the Yangtze Estuary.

Coastal marshes have a significant capacity to sequester carbon; however, sea-level rise (SLR) is expected to result in prolonged flooding and saltwater intrusion in coastal regions. To explore the effects of SLR projections on net CO

Coastal plants have unique adaptability to cope with strong hydrological stresses in tidal wetlands. A fundamental understanding of the establishment and maintenance of coastal plants is needed for conservation and restoration. In the Yangtze Estuary, the plasticity of the morphological and reproductive traits of a pioneer Scirpus species (sedge), in terms of phenotypic growth, biomass allocation, and sexual and asexual reproductive traits, was investigated with increasing flooding intensity (elevation gradient) in a tidal flat. The varying response extents (thresholds) of plant zonation and morphological and reproductive traits to multiscale environmental heterogeneity were also assessed. Our results showed that plant colonization and performance at coastal frontiers are sensitive to the microtopography of elevation and reflect the ecological adaptability at both the landscape and individual scales. Sedge species typically exhibit morphological and reproductive flexibility across the inundation intensity. The plants allocated more biomass to belowground tissues in response to decreasing elevation. The elevation thresholds for the yield of reproductive organs were higher (2.38–2.50 m based on the local Wusong datum) than those for morphology (2.05–2.14 m). The thresholds for the yield of asexual reproductive organs shifted to a lower elevation by approximately 0.15 m relative to that of the sexual reproductive organs. The increasing corm: spike ratios of plants with longer inundation durations also indicated this reproductive plasticity. This study revealed that the combination of morphological and reproductive responses of pioneer sedges contributed to survival and colonization at the foremost coastal flat. Our results are useful for developing restoration strategies for the native Scirpus species on China's coast.

Combined effects of vegetation, tide and sediment on the carbon dynamics in the intertidal creek-marsh systems remain unclear. We investigated the variability of dissolved organic (DOC) and inorganic carbon (DIC), and particulate organic (POC) and inorganic carbon (PIC) in the tidal creeks within the Poaceae and Cyperaceae communities on flood-ebb cycle in a salt marsh of eastern China. In the Poaceae creek with high plant biomass and soil carbon stock, the DOC concentrations were higher by on average 1.00–1.48 times than that in the Cyperaceae creek across all seasons and spring and neap tide stages, while the difference of DIC was not notable. The POC and PIC concentrations were lower in the Poaceae creek compared to the Cyperaceae creek. Spring tides increased the carbon concentrations (except for PIC) in both creeks by on average 7–40%, relative to neap tides. Seasonal variations of sedimentary rate within the communities probably result in the discrepancy of particulate carbon loading between the creeks. The Poaceae creek functioned as a source of DOC and DIC throughout a year but as a sink of POC and PIC in summer and autumn, while it turned to a weak source of PIC in winter and spring. The Cyperaceae creek exhibited as a source of all carbon components throughout a year. We suggest that vegetation type (with soil carbon stocks), tidal regimes and sedimentary dynamics would synergistically determine the fate of carbon in the creeks. Our results are helpful in reliable estimates of carbon transport between the coastal marsh and the adjacent ocean.

Coastal marsh vegetation plays an important role in coastal protection by attenuating waves and mitigating shoreline erosion. However, the different vegetations show wide variability in biophysical properties on seasonal and spatial scales, and the effectiveness of coastal vegetation on wave attenuation remains uncertain. In the spring, summer, and autumn seasons of 2019, we investigated the spatiotemporal variability in vegetation properties and wave attenuating ability of two dominant marsh species, Scirpus mariqueter (short and flexible Cyperaceae) and Phragmites australis (tall and stiff Poaceae), in a coastal wetland in the Yangtze Estuary. The wave parameters and water depth were measured at the two marshes and ranged from 25 to 100 m landward of the low mudflat edge. The results indicated that the aboveground biomass and height of vegetation are crucial properties determining the ability of wave attenuation, and the pioneer vegetation belt has the highest wave dissipation efficiency. Phragmites, with greater biomass and stem structure, were more effective in reducing wave height than Scirpus. This study further revealed the importance of seasonal variability in vegetation growth in species-specific wave attenuation. Most Scirpus stems senesced and broke up from autumn onwards, losing their wave attenuation ability. Although Phragmites could not colonize the low-lying flats such as Scirpus, most Phragmites stems remained stiff and high biomass at the later growing stage, maintaining wave attenuation ability and wave decay values consistent with those observed in summer. Moreover, Phragmites has a great capacity to capture sediments and raise flat elevations, which might enhance the wave attenuation efficiency with vegetation-sediment interactions. Information from this study is helpful in evaluating the dynamic effectiveness of wave attenuation in coastal marshes. Therefore, we suggest that a hierarchical mixed community of Scirpus and Phragmites be established as an effective natural defense to offset their individual biological limitations due to seasonality and spatial niches.

Coastal marshes play a notable role in sequestering carbon in plants and soil; however, coastal ecosystems are vulnerable to global change in terms of sea-level rise and saltwater intrusion. The effects of independent and interactive hydrological treatments of waterlogging and elevated salinity on soil CO2 effluxes in Spartina alterniflora marshes were investigated based on a mesocosm approach. This study highlighted the importance of respective soil respirations during inundation (nondrainage, Rs.ND) and reaeration (drainage, Rs.D) in the marshes soils. We found that waterlogging treatments heavily suppressed Rs.ND but increased the Rs.D, regardless of salinity levels. Light salinity enhanced soil respiration, whereas high salinity inhibited soil CO2 efflux, regardless of the water table level. Waterlogging strengthened the negative effects of salinity on Rs.ND and offset the negative effects on Rs.D. The variations in soil respiration under the hydrological treatments can be mainly attributed to changes in root biomass; indigenous soil microbial biomass; and activities of sucrase, cellulase and dehydrogenase, as well as ionic concentrations and oxidation-reduction potential. The temperature sensitivity (Q10 value) of soil respiration (only for Rs.D) after drainage showed a notable decline under the conditions of waterlogging and high salinity. The effect degree of coupled hydrological treatments on soil respiration and Q10 values was similar to a single waterlogging factor before drainage and more strongly than a single factor after drainage. We suggest that the soil CO2 efflux under water flooding and reaeration, inundation duration, and salinity levels need to be considered to understand the impacts of future hydrological changes on coastal marshes.

The ecophysiological characteristics of native Phragmites australis and exotic Spartina alterniflora grown under waterlogging and salinity were investigated to explore their adaptation potential to sea level rise. The seasonal course of phenotypic traits, photosynthetic activity and chlorophyll fluorescence parameters of P. australis did not change remarkably under shallow flooding, whereas these variables were sensitive to increasing salinity. Waterlogging exacerbated the negative effects of salinity on shoot growth and photosynthetic activity of P. australis, and the combined stresses led to an absence of tassel and reproductive organs. By contrast, S. alterniflora performed well under both stresses and showed an obvious adaptation of salt secretion with increasing salinity. Light salinity was the optimal condition for S. alterniflora, and the tassel growth, chlorophyll content and fluorescence characters under moderate stresses did not differ notably. The Na+ and Cl− concentrations in leaves of both species increased, and the K+ content decreased in response to salinity. Under moderate and high saline levels, the ion concentrations in S. alterniflora were maintained at relatively consistent levels with increased salt secretion. We expect the degradation of P. australis and further colonization of S. alterniflora under prolonged flooding and saltwater intrusion from sea level rise on the coastline of China.

Coastal salt marshes are biogeomorphic ecosystems with coupled vegetation and hydro-sedimentary processes. A significant biogeomorphic feature with a positive loop between vegetation colonization, sedimentary accretion, and edge scarp progradation can be found in coastal marshes with a highly depositional environment, such as the Yangtze Estuary. Together with field surveys, we used a process-based salt marsh model to characterize the spatiotemporal dynamics of vegetation and geomorphology in a tidal wetland in the Yangtze Estuary from 2014 to 2019. This model incorporated interactions between biotic processes (plant growth, colonization, and hydrological resilience) and abiotic processes (tidal transport of propagules, sediment inputs, and habitat-specific sediment deposition). Comparisons with field measurements showed that the model satisfactorily described the interannual variations in vegetation growth and lateral expansion, sedimentary dynamics and elevation change, and formation of marsh-edge scarps at two investigation sites. In particular, both observation and simulation revealed that the degree of sediment supply regulated the rates of vegetation behavior and geomorphic changes. The rates of plant establishment and growth were higher at the site with high sediment supply, and a higher rate of vegetation expansion and sedimentary accretion drove a faster seaward progradation of marsh-edge scarps, compared to the site with low sediment supply. Our results indicate that the interactions between biotic and abiotic processes, together with sediment supply, strongly determine the heterogeneity of marsh biogeomorphology in a highly depositional system. Thus, there is a vast potential for application of process-based models in formulating tidal wetland management and assessing future system resilience.

Recruiting native coastal vegetation and preventing the reinvasion of exotic Spartina alterniflora is a major challenge in China, due to harsh tidal environment for vegetation establishment and rapid Spartina colonization. This paper first reviewed the revegetation course of native Scirpus mariqueter in a coastal wetland in the Yangtze Estuary, where the adjacent Spartina was effectively eliminated. From 2014 to 2019, the area of planted Scirpus increased by 26.7 times, and the plant density and biomass growth amounted to the levels of mature sedge community. The establishment of Scirpus promoted the sedimentary accretion with an annual sedimentary rate of 9.2 cm yr−1, which was significantly higher than that in the mudflat. Six years of monitoring revealed that the revegetation approach with belowground propagules (corms) was effective for Scirpus establishment under strong hydrodynamic disturbances in the tidal mudflat because the morphology and germination rate of corms benefited the anchoring function of seedlings. Both recruited Scirpus and the original community expanded constantly due to positive feedback between plant progradation and sedimentary accretion. Then, we implemented a model simulation under the scenario of Spartina retention. The prediction showed that the high-speed invasion of Spartina would colonize and replace the whole Scirpus community in the study area during the period of 2014–2019. Hence, our results highlighted the importance of coupling Scirpus recruitment with Spartina eradication in guaranteeing recolonization of native coastal sedges. As a long-lasting management strategy, unremitting field monitoring and assistant decision-making tools (such as the forecasting models) on Spartina reinvasion risk are highly suggested for preserving the restoration of native marshes.

The spatial-temporal evolution of land use and land cover (LULC) and its multi-scale impact on the water environment is becoming highly significant in the LULC research field. The current research results show that the more significant scale impact on LULC and water quality in the whole basin and the riparian buffer scale is unclear. A consensus has not been reached about the optimal spatial scale problem in the relationship between the LULC and water quality. The typical lake basin of the Fuxian Lake watershed was used as the research area and the scale relationship between the LULC and water quality was taken as the research object. High resolution remote sensing images, archival resources of surveying, mapping and geographic information, and the monitoring data of water quality were utilized as the main data sources. Remote sensing and Geometric Information Technology were applied. A multi-scale object random forest algorithm (MSORF) was used to raise the classification accuracy of the high resolution remote sensing images from 2005 to 2017 in the basin and the multi-scale relationship between the two was discussed using the Pearson correlation analysis method. From 2005 to 2017, the water quality indicators (Chemical Oxygen Demand (COD), Total Phosphorous (TP), Total Nitrogen (TN)) of nine rivers in the lake’s basin and the Fuxian Lake center were used as response variables and the LULC type in the basin was interpreted as the explanation variable. The stepwise selection method was used to establish a relationship model for the water quality of the water entering the lake and the significance of the LULC type was established at p

Revegetation of pioneer plants is a critical phase in community establishment for mudflats in seriously degraded coastal wetlands. We tested a hypothesis of the importance of a "power balance" among propagule resilience and sedimentary and tidal disturbances for vegetation reestablishment. Our experiment used three types of propagules (seeds, seedlings, and corms) of native Scirpus species in the fringing flats with similar tidal flows and varying sedimentary intensities in the Yangtze Estuary. Regardless of the initial planting densities, the seed germination rate was extremely low in the field situation. Although the incubated seedlings were planted directly on the bare flat, the wave movement easily flushed the seedlings, even at the site with moderate sedimentary accretion. Failure of the revegetation practice using the seed and seedling materials indicated that the combined "growing and anchoring power" of young seedlings and "stabilizing power" of the sediment were insufficient to withstand the "dislodging power" of the tidal energy. In contrast, the planting approach with underground propagules (corms) proved to be feasible for vegetation establishment at the sites with moderate and low-level sedimentary intensities. The successful practice improved the tipping point of plant survival and tussock formation could be surpassed when the combined growing and anchoring power of seedlings that developed from corms with the stabilizing power of the sediment was greater than the dislodging power of the wave energy. However, at the site with high-level sedimentary intensity, the excessive sediment converted to the burying stress power as seedlings developed from the corms, revealing a burial threshold for seedling survival. The risk of seedling establishment was high when the burying stress power of the sediment far outweighed the combination of the growing power of the seedlings and the sediment removal power of the tidal current and surpassed the tipping point of vegetation die-off. Additionally, we checked the practice cost of the different approaches to ensure a highly cost-effective revegetation planning based on site suitability. This study highlights that understanding of the propagule-sediment-tide power balance offers a tool for improvement of the revegetation and management of site-specific sedimentary and hydrological environments for many degraded coastal ecosystems.

Intertidal creeks play an important role in transporting nutrients between coastal ecosystems and ocean. Reclamation is a predominant anthropogenic disturbance in coastal regions; however, the influence of reclamation on carbon and nitrogen species and greenhouse gas (GHG) fluxes in creek remains unclear. In a subtropical salt marsh of eastern China, the seasonal patterns of dissolved carbon (DOC, DIC, CO2, and CH4) and inorganic nitrogen (NH4+-N, NO2−-N, and NO3−-N and N2O) species, and the diffusive fluxes of CO2, CH4, and N2O, were compared between the natural tidal creeks and the reclaimed creeks. Due to notably changed hydrological and biological conditions in the reclaimed creeks, concentrations of all dissolved carbon species, NH4+-N and NO2−-N increased significantly by 60.2–288.2%, while NO3−-N and N2O decreased slightly, compared to the natural tidal creeks. DIC and NO3−-N were the primary components of the total dissolved carbon and inorganic nitrogen in both creek types; however, their proportions decreased as a result of elevated DOC, CO2, CH4, NH4+-N, and NO2−-N following reclamation. Significantly higher global warming potential (0.58 ± 0.15 g CO2-eq m−2 d−1) was found in the reclaimed creeks, making them hotspot of greenhouse effects, compared to the natural tidal creeks. Our results indicated that changes in flow velocity, salinity, Chlorophyll a, and pH were the main factors controlling the dissolved carbon and nitrogen and consequent GHG emissions, due to reclamation. This study is helpful in understanding of carbon and nitrogen sink-source shifts resulting from land use changes in coastal wetlands.

To observe the influence of repeated shallow fire-needle acupuncture stimulation plus cupping on local neuralgia and serum substance P(SP)content in patients with acute herpes zoster (AHZ).A total of 60 cases of AHZ patients were randomly divided into control (medication) group and treatment (medication plus fire-needle) group (After the treatment, the VAS scores and serum SP concentrations in both groups were significantly decreased in comparison with those of their own pre-treatment (Repeated shallow fire-needle stimulation plus cupping can accelerate the relief of local neuralgia in AHZ patients, which may be associated with its effect in down-regulating serum SP level.

Alternative stable states phenomenon widely exists in a variety of ecosystems and is closely related to ecosystem health and sustainable development. Although alternative stable states research has become the focus and hotspot of the ecology researches, only a few empirical evidences supported its behavior and mechanisms in coastal wetland ecosystems up to now. In our study, ta-king the intertidal wetland ecosystem in Chongming Dongtan Nature Reserve as study area, we aimed to: 1) test the existence of alternative stable states based on judgment conditions (bimodal characteristic and threshold effect) and determine the relative stable state types; 2) explore the formation mechanisms of alternative stable states by monitoring hydrological conditions, sediment accretion dynamics as well as vegetation growth parameters and analyzing the positive feedbacks between saltmarsh vegetation and sedimentary geomorphology. Our results showed that: 1) Normalized difference vegetation index (NDVI) frequentness distribution revealed obvious bimodality at saltmarsh pioneer zone. Propagule biomass threshold limited the establishment of plant patches representing the "saltmarsh" state. The presence of bimodality and biomass threshold demonstrated there are "mudflat" stable state and "saltmarsh" stable state with distinct structure and function in intertidal wetland ecosystem. 2) Current velocities, turbidities and direction perpendicular to the vegetation zone were the most important factors responsible for the sediments rapid accretion at saltmarsh pioneer zone in spring and summer. Sediments accretion significantly promoted the growth of saltmarsh plant. The positive feedbacks between plant growth and sediments accretion resulted in the formation of alternative stable states. 3) The expansion pattern of saltmarshes in the Chongming Dongtan intertidal wetland ecosystem also suggested that increases of sediments accretion could trigger the formation of "mudflat" stable state and "saltmarsh" stable state on landscape scale. The results from this study could enrich regime shift mechanisms researches and provide the scientific supports for coastal zone protection, restoration and comprehensive management, which could have important theoretical and practical meaning.多稳态现象普遍存在于多种生态系统中,它与生态系统的健康和可持续发展密切相关,已成为生态学研究的热点与难点,但是目前有关滨海湿地生态系统多稳态的形成机制还缺乏深入研究.本文以崇明东滩鸟类自然保护区的潮间带生态系统为研究对象,通过以下内容,开展滨海湿地多稳态研究: 1)通过验证多稳态的判定依据“双峰”和“阈值”特征,证实长江口潮间带生态系统存在多稳态,并确定其稳态类型;2)通过监测潮间带生态系统水动力过程、沉积动力过程以及盐沼植物生长和扩散情况,分析盐沼植被与沉积地貌之间的正反馈作用,进而探讨潮间带生态系统多稳态的形成机制.结果表明: 1)潮间带生态系统的归一化植被指数(NDVI)频度分布存在明显的双峰特征,且盐沼植物成活存在生物量阈值效应,均证实潮间带生态系统存在多稳态,“盐沼”和“光滩”是潮间带生态系统的两种相对稳定状态;2)崇明东滩盐沼前沿的沉积地貌表现出泥沙快速淤积的趋势,显著促进了盐沼植物的生长,盐沼植物与泥沙淤积之间的这种正反馈作用是潮间带生态系统形成多稳态的主要原因;3)盐沼植被扩散格局监测结果在景观尺度上也表明,泥沙淤积作用促进了潮间带生态系统“盐沼”和“光滩”多稳态的形成.本研究既丰富了滨海湿地稳态转换的机理研究,也为我国开展海岸带保护、修复和管理提供了科学依据,具有重要的理论和实践意义.

To investigate the relationship between relapse and the levels of the residual amount of HBV DNA in serum at cessation in chronic hepatitis B patients meeting 2008 Asian Pacific Association for the Study of the Liver (APASL) nucleos(t)ide analogs (NAs) cessation criteria.A total of 72 chronic hepatitis B patients who took NAs and had reached 2008 APASL cessation criteria entered the study. Patients were followed up for 6 months or longer after antiviral therapy was stopped. Serum HBV DNA level at cessation was detected by a highly sensitive polymerase chain reaction assay with detection limitation of 2 IU/mL.Of all the 72 patients, 42 patients (65.3%) relapsed after NA cessation. The detectable rate of the trace amount of HBV DNA at cessation was 41.7% by highly sensitive polymerase chain reaction reagents. The detectable rate of patients with consolidation treatment duration of18 months was higher than that with consolidation duration of ≥18 months (47.5% vs. 15.4%, P=0.034), and the detectable rate of patients with HBeAg seroconversion within 6 months of treatment was lower than that of ≥6 months (25.0% vs. 61.5%, P=0.036). The residual amount of HBV DNA and detectable rate at cessation showed significant differences between relapsed and nonrelapsed patients (130.4±420.90 vs 44.6±155.16 IU/mL, P=0.004; 55.3% vs. 16.0%, P=0.001). The cutoff value predicting relapse was 2.24 IU/mL, with a sensitivity of 0.553 and specificity of 0.840.Residual amount of HBV DNA in serum at NA cessation is associated with HBV relapse. The cutoff value predicting relapse was 2.24 IU/mL, with a sensitivity of 0.553 and specificity of 0.840.

Power grid crises at home and abroad happened frequently, insufficient research on power grid crisis management and awareness of “crisis and crisis management” warns the necessity and urgency of power grid crises management. Necessity of finding rational theoretical basis for our studying crisis and carrying out crisis management are becoming urgent. This article proposes the theoretical basis from three aspects: stage-division theory, system theory and structure theory. Stage-division of power grid crisis management can be adopted according to practical study. The outstanding performances of all components of crisis management embody the safe and stable operation of power system. Fragmentation of thinking way in power grid crisis management will hamper the crisis management, and we should establish “systems thinking”- “to see the whole”.

Power grid crisis happening at home and abroad warns the necessity of carry out power grid crisis management. Power-grid crisis management game is a zero sum game between power grid crisis manager and crisis event. Power-grid crisis game belongs to the “dynamic game of incomplete information”-“dynamic Bayesian game”. Dynamic Bayesian game process is just analogous to the process of crisis management of power grid, which fully demonstrates that the process of power-grid crisis management is a course of repeated game between crisis manager and power-crisis, also a constantly optimized process. This article mainly studies: the specific characteristics of dynamic Bayesian game of grid crisis management; the Dynamic game model of power grid crisis management; the calculation of refined Bayesian equilibrium principles.

There are few enterprises in economy scale among the majority of enterprises in industrial clusters, and they cannot carry out independent research-and-development of new products. Therefore, they have to rely on innovating resources of the clusters to enhance their comprehensive strength in competition. In this study, we analyzed the driving forces for collective learning in industry clusters, and try to establish a model for collective learning and competitiveness of industry clusters, and provided a new approach for upgrading industrial clusters.

Black start of power system is an issue of typical semi-structural optimization. Black-start scheme of power-grid recovery should have one or more alternative plans, when one project due to some special links cannot be successfully implemented, the other can quickly be implemented, so as to ensure the success rate of black-start crisis recovery. The preplan of crisis management requires the effective plan of crisis disposal, especially the preplan of black-start-path must be established, because effective recovery-path program can obtain an effective disposal of crisis to prevent the spread of the crisis. It is by the model of DEA that can evaluate the relative efficiency of the same type of black-start-path with multiple input, multiple output indexes, so as to identify gaps and improve the factors that affect the efficiency. So we chose the DEA model to evaluate the selection-path of black-start.

Power grid crisis happening at home and abroad warns the urgency of power grid crisis management. This article mainly study on how to carry out power grid crisis management under the natural disasters in extreme weather from three aspects: prevention and early warning before the crisis; coordination and joint action in crisis; reflections after the crisis. For the nucleus of crisis management is prevention-oriented, so the first line of defense of power grid crisis management is to establish a shared value of the crisis culture. In the face of power-grid crisis, a comprehensive “multi-sectoral” and “internal and external” coordination-mechanism must be built to jointly cope with the crisis. Through reflections after the crisis, inefficiency in disposal and long-term plan could be found timely so as to adjust preplan, early warning, long-range plans, and so on.

Power grid crisis that have taken place at home and abroad warns the importance of power grid crisis management. This paper studies the development of the theory on power grid crisis management. Deficiency of the traditional human-intelligence decision-making rule indicates the necessity of research on Online Intelligent Decision-making System of Power-grid Security based on Data Mining. This paper also introduces the development of relevant theory and its concrete application. Research on the above will have profound significance for China to deal with power grid crisis.

Power grid crisis happening at home and abroad warns the urgency of power grid crisis management. It is necessary to research on online intelligent decision-making system of power-grid security based on data mining. This paper studies the status of foreign online intelligent decision-making system of power-grid security and the concrete application of foreign online intelligent decision-making system of power-grid security. Based on advanced data mining technology, by online updating safety limit-rules and automatically digging out the running rules, the safe limit values are in line with actual condition of power-grid, dispatchers can adjust the grid by running this limit and can obtain a larger cross-section delivery power-flow. In such a way, it not only can ease the power shortage situation of the system, but also improve poor power transmission ability, and produce economic benefits.

The thinking of sustainable development not only respects the intrinsic value of nature, but also defines the human beings transcendent position in the world. At the same time, it determines specifically human subjectivity in the practice, and admits the legitimacy that humans use and transform the nature. Based the understanding of distinction between heaven and man, Tsunzi specifically set forth the eco-ethics practice theory of adapting the law of heaven and making use of it. His theory dialectically integrated human utilization, protection, rights, and obligations to nature, which not only involved human moral courage, but also embraced ecological moral principles of human practice as well as the ethical spirit of pursuing ecological ethic aims.

The nuclear contents of the ecological thought of ethics are harmonious development between man and nature, which is the basic demand for constructing the harmonious society. The Confucianists have all along attached great importance to the relations between man and nature. Tsunzi, a master on the Confucianism, made the conception of sustainable development penetrate into his ecological ethics thoughts on the basis of philosophical thinking of distinction between heaven and man. He not only put forward the consciousness of ethics practice-Adapting the law of heaven and making use of it.; but also advocate ecological moral responsibility-Prudently observing the ban on seasonal rules of nature.There will be some significant enlightening value for us to not only establish the theory of environmental ethics but also solve the increasing ecological crises facing humanity.

Tsunzi understood completely the distinction between heaven and man, and laid emphasis on separate duty of heaven and man. The bounden duty of heaven belongs to the nature, and heaven has no will; while the duty of man pertained to the society, the society is conscious human activity. As to the relationship between heaven and man, he emphasized that man can recognize the heaven, that is to say , man can recognize the natural law, and make use of the nature. Especially, regarding man the most precious beings in the whole of creation as his foothold, Tsunzi laid stress on human activity and subjectivity. This article analyzes Tsunzi's ecological objective of oustainable development: Heaven Correlating with man; the establishment of subject status of man to nature; materialization of the ecological ethics goals.

Ecology is the science of studying the relationship between the living organisms and their environment. And the Environmental Science, which reveals the basic law of the harmonious development of society, economy and environment, is the discipline studying the interaction of people and environment. Ecology is not only the basic disciplines of environmental science, but also the scientifically recognized theoretical basis of environmental ethics. Tsunzi, a master on the Confucianism, one of the most distinguished Confucianists of the pre-Qin period, made the conception of sustainable development penetrate into his ecological ethics thoughts on the basis of philosophical thinking-Nature has its true law. If we hackle, inherit, comprehend, and utilize critically Tsunzis thought on ecological ethics, there will be some significant enlightening value for us to not only establish the theory of environmental ethics but also solve the increasing ecological crises facing humanity.