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With the frequent occurrence of geological disasters and extreme weather, pipeline failure accidents and secondary disasters caused by debris flow continue to occur. Aiming at the impact of thin debris flow on support pipeline, a multi-physical coupling model of debris flow and support pipeline with vibration reduction is established based on the expansion flow model. The expansive fluid model is used to simulate the stress of the support pipeline under the action of thin debris flow. The results show that the impact effect of thin debris flow slurry on the support pipeline is concentrated at the inlet surface of the pipeline and the support, and gradually decreases to both ends. As the velocity of debris flow slurry increases, the stress acting on the support pipeline also increases. When the flow field tends to be stable, the load acting on the support pipeline maintains a stable value. The leading effect of debris flow slurry is the most serious damage to the support pipeline. The research results have a certain reference value for the impact of dilute debris flow in support pipeline.

Many strains of Pseudomonas colonise plant surfaces, including the cherry canker pathogens, Pseudomonas syringae pathovars syringae and morsprunorum. We have examined the genomic diversity of P. syringae in the cherry phyllosphere and focused on the role of prophages in transfer of genes encoding Type 3 secreted effector (T3SE) proteins contributing to the evolution of virulence. Phylogenomic analysis was carried out on epiphytic pseudomonads in the UK orchards. Significant differences in epiphytic populations occurred between regions. Nonpathogenic strains were found to contain reservoirs of T3SE genes. Members of P. syringae phylogroups 4 and 10 were identified for the first time from Prunus. Using bioinformatics, we explored the presence of the gene encoding T3SE HopAR1 within related prophage sequences in diverse P. syringae strains including cherry epiphytes and pathogens. Results indicated that horizontal gene transfer (HGT) of this effector between phylogroups may have involved phage. Prophages containing hopAR1 were demonstrated to excise, circularise and transfer the gene on the leaf surface. The phyllosphere provides a dynamic environment for prophage-mediated gene exchange and the potential for the emergence of new more virulent pathotypes. Our results suggest that genome-based epidemiological surveillance of environmental populations will allow the timely application of control measures to prevent damaging diseases.

Objective: To investigate the role of ferroptosis in Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) with renal injury. Methods: GSE104954 and GSE108112 were retrieved from the GEO database and concatenated into one dataset. Expression of ferroptosis-related genes (FRGs) was extracted for differential analysis. The ferroptosis signature genes were identified by LASSO regression and SVM-RFE, and their differential expression levels and diagnostic efficacy were verified by independent data sets. The ceRNA (miRNA-TF-mRNA) regulatory network and clinical diagnostic model were constructed respectively. By using consensus clustering, ferroptosis subtypes were identified. ssGSEA and GSVA were employed to assess immune response and pathway activation. Pan-cancer genes were found in TCGA and GTEx. Differential expression of CD44 in was validated by qPCR and immunohistochemistry from HPA database. Results:Twenty-four FRGs were differentially expressed in patients with AAV kidney injury. Furthermore, five ferroptosis signature genes were identified by two machine learning algorithms. Not only were differentially expressed in independent datasets, the clinical diagnostic model constructed by these genes provided reference for clinical decision-making, but also the ceRNA network revealed their complex regulatory mechanisms. Unsupervised clustering analysis discovered two ferroptosis subtypes with distinct gene expression, immunological microenvironment, and biological functioning pathways. Notably, CD44 was found to be closely associated with many immune cells, most immune responses, and HLA genes, as well as prognosis, immune cell infiltration, TMB, and MSI in patients with a variety of tumors, suggesting it may be a potential intervention target for human diseases including AAV renal injury and tumors. Conclusions:Ferroptosis in AAV with renal injury is significantly correlated with the immunological microenvironment. For AAV with renal injury and tumors, CD44 could be a useful intervention target.

Sustainability indicators are essential technical tools for monitoring and managing sustainable urban development. The challenge of developing sustainability indicators in the urban context lies in the lack of a participatory approach that integrates the bottom-up perspective of citizens. Therefore, taking the 14th Five-Year Plan development indicators in the West Bund of Shanghai as the case study, this paper provides policy recommendations for the readjustment and iteration of the local indicators for the Xuhui District Government by identifying the local citizens’ viewpoints and investigating its differences with the policymakers’ views. Totally ten local participants were involved in the structured interviews. Holistically, the perspective of local citizens presents the features of actively intervening in community governance, prioritising community benefits, and trusting the decision-making of local policymakers. This paper then argues that policymakers in a dominant position with preferences in economic indicators should take the initiative to provide an increase in facility-based indicators, effective feedback channels, and professional training in sustainability for local citizens in a secondary position who focus on the improvement of their living experience. The outcomes contribute to the materialisation of the West Bund’s governance goals and the further refinement of integrated solutions for sustainability indicator development.

Exoplanet transit timing variation is a method to find exoplanets. To understand this method better, I wrote a computer program in python to simulate the transit of exoplanets. I use my program to simulate the transit timing variation observed in the Kepler-19 system. I make a simple simulation of Kepler-19 system, and this simulation shows that the variation in transit timing due to other planets is very obvious for Kepler-19b, the transiting planet, which means the transit timing variation method is very useful for finding exoplanet in Kepler-19 system. The whole paper is an illustration for that. The simulation I make is relatively simple but it still corresponds to the law of TTV, and because of its simplicity, it can help more people understand.

Terrestrial water storage is a crucial component in water cycle and plays an important role in flood formations process, particularly in a changing environment. In this study, we aim to examine the future variation of terrestrial water storage anomaly (TWSA) and associated flood potential in one of the most flood-prone regions, the Yangtze River basin in China. Using the Gravity Recovery and Climate Experiment (GRACE) data, we perform bias correction for seven general circulation models (GCMs) from the Coupled Model Intercomparison Project Phase 6 under three Shared Socio-economic Pathway (SSP) scenarios: SSP126, SSP245, and SSP585. The spatiotemporal characteristics of changes in future Flood Potential Index are projected and compared between the near (2031-2060) and far (2071-2100) future with reference to the historical period (1985-2014). The results show that GCMs-simulated TWSA generally agrees well with the GRACE results after downscaling and bias correction with the average correlation coefficient of 0.86, Nash-Sutcliffe efficiency of 0.73 and the root mean square error of 21.68 mm. We found that the total variance of projected TWSA is mainly sourced from the internal variability and model uncertainties, while the uncertainties in scenarios contribute relatively less. Moreover, the flood potential is projected to decline during the near future under various scenarios and even lower during the far future under SSP585 scenario. Our findings provide implications for flood control and management under climate change over high flood risk regions worldwide.

Herein, two bis(dicyanomethylene)-substituted quinoidal molecules QBDT and QTBDT-3H were designed and synthesized to explore the open-shell effect on tuning the charge transport behavior of organic...

In the summer of 2016, severe storms caused serious casualties and destruction of facilities and properties over South China. Near-real-time (NRT) satellite precipitation products are attractive to rainstorm monitoring and flood warning guidance owing to its combination of timeliness, high spatiotemporal resolution, and broad coverage. We evaluate the performance of four NRT satellite products, i.e., Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks, 3B42RT, Global Satellite Mapping of Precipitation (GSMaP) NRT, and Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) Late run using a high-quality merged product in the rainy June over South China. In addition, a method based on an empirical flash flood guidance and the Flash Flood Potential Index is proposed to examine the applicability of satellite products in guiding flood warning. The IMERG Late run and GSMaP NRT perform the closest-to-ground observations. 3B42RT detects the most flood warning events due to its notable overestimation of actual precipitation. We recommend that the IMERG Late run is the best NRT satellite product in capturing flood hazard events according to the Pareto Efficiency of jointly optimizing higher hit ratio and lower false alarms.

The United States Natural Resources Conservation Service (NRCS) Runoff Curve Number (CN) is the most widely used rainfall-runoff modeling method. The hydrologic soil group (HSG), land use/cover, hy...

Bacteriophages are obligate intracellular parasites of bacteria. Some bacteriophages can confer novel bacterial phenotypes, including pathogenicity, through horizontal gene transfer (HGT). The pathogenic bacterium Citrobacter rodentium infects mice using mechanisms similar to those employed by human gastrointestinal pathogens, making it an important model organism. Here, we examined the 10 prophages of C. rodentium , investigating their roles in its evolution toward virulence. We characterized ΦNP and ΦSM, two endogenous active temperate bacteriophages likely important for HGT. We showed that the 10 prophages encode predicted virulence factors and are conserved within other intestinal pathogens. Phylogenetic analysis suggested that they represent a conserved family of horizontally acquired enteric-bacterium-associated pathogenic determinants. Consequently, similar analysis of prophage elements in other pathogens might further understanding of their evolution and pathology.

Bacteriophages are viral parasites of bacteria. A successful infection starts with the adsorption of the bacteriophage to a specific receptor on the host cell surface. Most bacteriophages are thought to have a narrow host range but this can be extended in certain cases. One strategy forextending host range is to first express a known functional bacteriophage receptor protein in bacteria previously non-susceptible to the bacteriophage, thereby enabling adsorption and potential infection by viruses that target the specific receptor. To investigate the feasibility of this approach, a plasmid (pMUT13) encoding the Escherichia coli LamB porin, the receptor for bacteriophage Lambda, was transferred into three different enterobacterial genera, namely Citrobacter, Yersinia, and Serratia. Over 100 environmental bacteriophages were isolated that infected these pMUT13-containing strains, and some bacteriophages were shown to infect their respective hosts in a LamB-dependent way. The host ranges of the environmental bacteriophages were cross-tested across the heterologous genera and surface adsorption kinetics investigated. Unlike bacteriophage Lambda, which is a member of the Siphoviridae, these newly-isolated LamB-dependent bacteriophages were more commonly members of the Myoviridae, based on transmission electron microscopy and whole genome sequences. Furthermore, an interesting selection of evolved bacteriophage mutants with broader host range were isolated, and the key mutations involved in their evolution to adapt to new hosts were investigated by genome analysis.

Hydro-meteorological datasets are key components for understanding physical hydrological processes, but the scarcity of observational data hinders their potential application in poorly gauged regions. Satellite-retrieved and atmospheric reanalysis products exhibit considerable advantages in filling the spatial gaps in in-situ gauging networks and are thus forced to drive the physically lumped hydrological models for long-term streamflow simulation in data-sparse regions. As machine learning (ML)-based techniques can capture the relationship between different elements, they may have potential in further exploring meteorological predictors and hydrological responses. To examine the application prospects of a physically constrained ML algorithm using earth observation data, we used a short-series hydrological observation of the Hanjiang River basin in China as a case study. In this study, the prevalent modèle du Génie Rural à 9 paramètres Journalier (GR4J-9) hydrological model was used to initially simulate streamflow, and then, the simulated series and remote sensing data were used to train the long short-term memory (LSTM) method. The results demonstrated that the advanced GR4J9–LSTM model chain effectively improves the performance of the streamflow simulation by using more remote sensing data related to the hydrological response variables. Additionally, we derived a reservoir operation model by feeding the LSTM-based simulation outputs, which further revealed the potential application of our proposed technique.

Satellite-retrieved and atmospheric reanalysis precipitation can bridge the spatiotemporal gaps of in-situ gauging networks, but estimation biases can limit their reliable applications in hydrological monitoring and modelling. To correct precipitation occurrence and intensity simultaneously, this study develops a three-stage blending approach to integrate three multi-satellite precipitation datasets (IMERG Final, TMPA 3B42V7 and PERSIANN-CDR), the ERA5 atmospheric reanalysis product and a gauge dataset within a dynamic framework. Firstly, the systematic biases of the four members were individually corrected by combining the local intensity scaling and ratio bias correction methods. Then, the “state weights” used for determining wet/dry events were optimized by evaluating a score function of the four bias-corrected members. Thirdly, the “intensity weights” were optimized using the cuckoo search (CS) algorithm and the Bayesian Model Averaging (BMA) method, respectively. The three-stage blending approach produced dynamic weights varying both spatially and temporally, and the performance was thoroughly evaluated over mainland China. Results show that the three-stage dynamic scheme performs better than individual datasets and two-stage blending methods in terms of all eight statistical metrics, and the CS algorithm outperforms the BMA method in the third stage. By randomly sampling validation sites using K-fold experiments, the developed algorithm also demonstrates a superior performance in ungauged regions. After interpolating and normalizing blending parameters of all gauges to entire domain using ordinary kriging, a new blended precipitation dataset with a daily 0.25° scale was produced. Four hydrological models are forced by blended and primary precipitations in 238 catchments over China, further confirming that the developed approach can facilitate hydrological modelling demonstrated by improving the Kling-Gupta efficiency of simulated streamflow by 12–35%.

Yunnan Province, located in Southwest China, suffers from massive flash flood hazards due to its complex mountainous hydrometeorology. However, traditional flash flood forecasting approaches can hardly provide an effective and comprehensive guide. Aiming to build a multilevel guidance system of flash flood warning for Yunnan, this study develops a Cascading Flash Flood Guidance (CFFG) system, progressively from the Flash Flood Potential Index (FFPI), the Flash Flood Hazard Index (FFHI) to the Flash Flood Risk Index (FFRI). First, land cover and vegetation cover data from MODIS products, the Harmonized World Soil Database soil map, and SRTM slope data are used in generating a composite FFPI map. In this process, an integrated approach of the analytic hierarchy process and the information entropy theory is used as a weighting method. Then, three standardized rainfall amounts (average daily amount in flood seasons, maximum 6 h and maximum 24 h amount) are added to derive FFHI. Further inclusion of GDP, population and flood prevention measures as vulnerability factors for the FFRI enabled prediction of the flash flood risk. The spatial patterns of the CFFG indices indicate that counties in east Yunnan are most susceptible to flash floods, which agrees with the distribution of observed flash flood events. Compared to other approaches, the CFFG system could be a useful prototype in mapping characteristics of China’s flash floods in a cascading manner (i.e., potential, hazard and risk) for users at different administrative levels (e.g., town, county, province and even nation).

The goal of this study is to quantitatively intercompare the standard products of the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) and its successor, the Global Precipitation Measurement (GPM) mission Integrated Multisatellite Retrievals for GPM (IMERG), with a dense gauge network over the midlatitude Ganjiang River basin in southeast China. In general, direct comparisons of the TMPA 3B42V7, 3B42RT, and GPM Day-1 IMERG estimates with gauge observations over an extended period of the rainy season (from May through September 2014) at 0.25° and daily resolutions show that all three products demonstrate similarly acceptable (~0.63) and high (0.87) correlation at grid and basin scales, respectively, although 3B42RT shows much higher overestimation. Both of the post-real-time corrections effectively reduce the bias of Day-1 IMERG and 3B42V7 to single digits of underestimation from 20+% overestimation of 3B42RT. The Taylor diagram shows that Day-1 IMERG and 3B42V7 are comparable at grid and basin scales. Hydrologic assessment with the Coupled Routing and Excess Storage (CREST) hydrologic model indicates that the Day-1 IMERG product performs comparably to gauge reference data. In many cases, the IMERG product outperforms TMPA standard products, suggesting a promising prospect of hydrologic utility and a desirable hydrologic continuity from TRMM-era product heritages to GPM-era IMERG products. Overall, this early study highlights that the Day-1 IMERG product can adequately substitute TMPA products both statistically and hydrologically, even with its limited data availability to date, in this well-gauged midlatitude basin. As more IMERG data are released, more studies to explore the potential of GPM-era IMERG in water, weather, and climate research are urgently needed.

Monitoring changes in flood extent is critical for flood control and mitigation purposes in areas where flooding affects many people and dense infrastructure and properties. Remote sensing can be an effective technique to detect changes in surface water extent and its dynamics. Compared to optical remote sensing, microwave information is suitable for working in any weather condition without severe cloud interference. Usually passive microwave data has a high temporal but a rather coarse spatial resolution, whereas for active microwave data this is reversed and only with ideal satellite constellation observations it can reach high sampling rates. To overcome these spatial and temporal restrictions, we proposed an integrated methodology to combine the passive and active microwave remote sensing and thus provide flood information more frequently at a high resolution. In this paper, a demonstration of the methodology is presented for a flood event occurring in Wuhan, Hubei Province of China in July 2016. The major inundation occurred along the Jushui River, part of the Middle Yangtze River basin. Using the brightness temperature data from a special data set (MEaSUREs), a daily passive microwave signal at the resolution of 3.125 km is used as an indicator to monitor flood occurrence and obtain the flood duration over time. Synthetic Aperture Radar (SAR) imagery (12-day revisit, 10-m spatial resolution) from Sentinel-1 was processed to estimate high resolution flood extents within the time span of the flood based on a threshold-based method together with the High Above Nearest Drainage (HAND) index post-processor. Surface water fraction data generated from SAR images presents a strong correlation with the passive microwave signal (R2 = 0.84) when using a quadratic polynomial fit. The average bias between surface water fraction computed by the passive microwave signals and SAR observations for water pixels within the Jushui River basin for the validation dates is 0.34%, indicating that this relationship can be applied to interpolate surface water fraction for each pixel along the river and other permanent water bodies for days when SAR observations are not available. This integrated method takes advantage of both passive and active microwave remote sensing and enriches temporally sparse flood data. Given the global coverage of the datasets used in this study, it can be utilized to estimate flood status for other flood-prone areas and thus contribute towards societal flood preparedness and response.

Bacteriophages are obligate intracellular parasites of bacteria. Some bacteriophages can confer novel bacterial phenotypes, including pathogenicity, through horizontal gene transfer (HGT). The pathogenic bacterium Citrobacter rodentium infects mice using mechanisms similar to those employed by human gastrointestinal pathogens, making it an important model organism. Here, we examined the 10 prophages of C. rodentium, investigating their roles in its evolution toward virulence. We characterized ΦNP and ΦSM, two endogenous active temperate bacteriophages likely important for HGT. We showed that the 10 prophages encode predicted virulence factors and are conserved within other intestinal pathogens. Phylogenetic analysis suggested that they represent a conserved family of horizontally acquired enteric-bacterium-associated pathogenic determinants. Consequently, similar analysis of prophage elements in other pathogens might further understanding of their evolution and pathology., Prophage-mediated horizontal gene transfer (HGT) plays a key role in the evolution of bacteria, enabling access to new environmental niches, including pathogenicity. Citrobacter rodentium is a host-adapted intestinal mouse pathogen and important model organism for attaching and effacing (A/E) pathogens, including the clinically significant enterohaemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC, respectively). Even though C. rodentium contains 10 prophage genomic regions, including an active temperate phage, ΦNP, little was known regarding the nature of C. rodentium prophages in the bacterium’s evolution toward pathogenicity. In this study, our characterization of ΦNP led to the discovery of a second, fully functional temperate phage, named ΦSM. We identify the bacterial host receptor for both phages as lipopolysaccharide (LPS). ΦNP and ΦSM are likely important mediators of HGT in C. rodentium. Bioinformatic analysis of the 10 prophage regions reveals cargo genes encoding known virulence factors, including several type III secretion system (T3SS) effectors. C. rodentium prophages are conserved across a wide range of pathogenic enteric bacteria, including EPEC and EHEC as well as pathogenic strains of Salmonella enterica, Shigella boydii, and Klebsiella pneumoniae. Phylogenetic analysis of core enteric backbone genes compared against prophage evolutionary models suggests that these prophages represent an important, conserved family of horizontally acquired enteric-bacterium-associated pathogenicity determinants. In addition to highlighting the transformative role of bacteriophage-mediated HGT in C. rodentium’s evolution toward pathogenicity, these data suggest that the examination of conserved families of prophages in other pathogenic bacteria and disease outbreaks might provide deeper evolutionary and pathological insights otherwise obscured by more classical analysis. IMPORTANCE Bacteriophages are obligate intracellular parasites of bacteria. Some bacteriophages can confer novel bacterial phenotypes, including pathogenicity, through horizontal gene transfer (HGT). The pathogenic bacterium Citrobacter rodentium infects mice using mechanisms similar to those employed by human gastrointestinal pathogens, making it an important model organism. Here, we examined the 10 prophages of C. rodentium, investigating their roles in its evolution toward virulence. We characterized ΦNP and ΦSM, two endogenous active temperate bacteriophages likely important for HGT. We showed that the 10 prophages encode predicted virulence factors and are conserved within other intestinal pathogens. Phylogenetic analysis suggested that they represent a conserved family of horizontally acquired enteric-bacterium-associated pathogenic determinants. Consequently, similar analysis of prophage elements in other pathogens might further understanding of their evolution and pathology.

NASA’s Cyclone Global Navigation Satellite System (CYGNSS) mission, launched in 2016, is a small satellite constellation designed to measure the ocean surface wind speed in hurricanes and tropical cyclones. To explore its additional capabilities for applications on the land surface, this study investigated the advantages and limitations of using CYGNSS data to monitor flood inundation during typhoon and extreme precipitation events in southeast China in 2017. The results showed that despite the lack of quantitative evaluation, the CYGNSS-derived surface reflectivity (SR) and flood inundation area was qualitatively consistent with the Global Precipitation Measurement (GPM)-derived precipitation and Soil Moisture Active Passive (SMAP)/Soil Moisture and Ocean Salinity (SMOS)-derived total brightness temperature at circular polarization ( T b C ). The results provide supporting evidence for further designation of Global Navigation Satellite System (GNSS) reflectometry (GNSS-R) constellations to monitor land surface hydrology.

Floods are one of the most devastating natural hazards around the world, and flash floods are extremely dangerous to property and human lives. This study reviews the current flash flood forecasting in China and proposes a new methodology to develop a flash flood potential index (FFPI) based on GIS to further improve China's flash flood guidance system and national weather forecasting services. We collected datasets required to calculate the FFPI and tested a series of schemes to determine the method to calculate the FFPI over China. The result indicates that the calculated China's FFPI distribution can represent the risk of flash flood well, especially in Central and Southeast China. It is also implied that the southwest and western complex terrains are more susceptible to rain storms. Then we chose Yunnan Province as a test-bed and also yielded good results which can offer reference to the current China's flash flood forecasting system. Further research can be placed on incorporation of soil moisture and rainfall frequency components into the FFPI calculation method for dynamic warning and forecasting of flash floods.