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Flash flood disaster ranks top among all the natural hazards across the world due to its high frequency, severity and fatality. However, flash flood simulation is still challenging in small and medium-sized catchments with complex orography, flashy hydrological responses and poor observations. Three distributed hydrological models, i.e., TOPModel, HEC and CNFF, are selected to simulate flash floods in seven humid and six semi-humid catchments in China, with consideration of water balance (RER), peak flow rate (REQ) and its occurrence time (TP), hydrograph variation (SNSE) and model uncertainty. Influences of five catchment attributes are further investigated on individual model performances. All three models perform satisfactorily in humid catchments, but less satisfactorily in semi-humid catchments. Water balance is well obtained by CNFF, followed by HEC and TOPModel. Peak flow rate and its occurrence time are most accurately captured by CNFF and HEC, respectively. Hydrograph variations are well reproduced by HEC and CNFF. TOPModel performs well for picking peak flow and hydrograph variation in humid catchments. Uncertainty interval is narrowest for HEC with average relative interval length at 95% confidence level being 0.78 ~ 2.53. Most observations are bracketed by uncertainty intervals for TOPModel (64.79% ~ 91.91% of total). Three model performance indices (i.e., RER, REQ, and SNSE) are mainly affected by drainage area and forest ratio across humid and semi-humid catchments, while TP performance is mainly affected by mean slope in humid catchments. [ABSTRACT FROM AUTHOR]

As an effective technique to improve the rainfall forecast, data assimilation plays an important role in meteorology and hydrology. The aim of this study is to explore the reasonable use of Doppler radar data assimilation to correct the initial and lateral boundary conditions of the numerical weather prediction (NWP) systems. The Weather Research and Forecasting (WRF) model is applied to simulate three typhoon storm events on the southeast coast of China. Radar data from a Doppler radar station in Changle, China, are assimilated with three-dimensional variational data assimilation (3-DVar) model. Nine assimilation modes are designed by three kinds of radar data and at three assimilation time intervals. The rainfall simulations in a medium-scale catchment, Meixi, are evaluated by three indices, including relative error (RE), critical success index (CSI), and root mean square error (RMSE). Assimilating radial velocity at a time interval of 1 h can significantly improve the rainfall simulations, and it outperforms the other modes for all the three storm events. Shortening the assimilation time interval can improve the rainfall simulations in most cases, while assimilating radar reflectivity always leads to worse simulations as the time interval shortens. The rainfall simulations can be improved by data assimilation as a whole, especially for the heavy rainfall with strong convection. The findings provide references for improving the typhoon rainfall forecasts at catchment scale and have great significance on typhoon rainstorm warning. [ABSTRACT FROM AUTHOR]

In recent years, flash floods and urban waterlogging have become a widespread phenomenon in Fuzhou, which pose a serious threat to people’s lives and property. The primary disaster-causing factors include the intensity and duration of rainfall. Therefore, this article analyzes the characteristics, causes of rainfall, and the existing problems of the two disasters in Fuzhou. The main conclusions are as follows: (1) The rainfall in Fuzhou is concentrated in March to September, with high rainfall intensity and rainfall amounts, and frequent extreme rainfall events combined with high rainfall intensity in flash flood-prone areas are higher than that in the plains area. (2) Precipitation, geographical conditions, and urban construction mainly caused the two major disasters and are weak in technology and management. Therefore, it is necessary to adhere to both the structural measures and non-structural measures to coordinate the relationship between people and floods, to strengthen the research on the mechanisms of precipitation, and to forecast and provide early warning of flash floods and urban waterlogging, all of which can provide reference for the defensive disasters in mountainous coastal cities. [ABSTRACT FROM AUTHOR]

The completion of Shuibuya, the last hydropower station to be constructed in the Qingjiang cascade, signifies China's successful development of the world's largest mixed cascade hydropower generation system. Joint operation of such cascaded hydropower stations is considered necessary to improve hydropower output in China. In this study, two modeling methods – routine and optimal operations – were adopted, based on existing rules of reservoir operation, to determine the effects of joint operation. To investigate the realistic and potential effects, the two models were computed using observed runoff data (1951–2009). The potential effects were identified by comparing the total hydropower generation two single cascades and their cogeneration. Under the routine operational mode, the incremental power generation of joint operation would be 5.73 × 10 8 kWh, an increase of 5‰ compared to isolated operation. However, even in isolation, if reservoir operation is optimized through the dynamic programming algorithm, the incremental power generation of the cascade would be 42.24 × 10 8 kWh, which is seven times that of joint operation with routine reservoir operation (5.73 × 10 8 kWh). The results showed that, under current reservoir operating rules, there is little room for improvement in hydropower generation, although joint operation could increase hydropower generation to a certain extent, especially in the reservoirs' refill and release stages. China must amend its existing operational mode for reservoirs to enhance the economic benefits of cascade hydropower stations. Furthermore, to meet increasing demands for both water and energy, carefully considered planning of constructing clusters of these stations is required. [ABSTRACT FROM AUTHOR]

Disasters caused by flash floods with casualties have occurred frequently in China in recent years. In order to effectively prevent and control them, the government initiated the project of building up a comprehensive non-structural measure system in 103 pilot counties from 2009. Based on the pilot experience, this project involved 2058 counties of 29 provinces and Xinjiang Production and Construction Corp from 2013. Analysis and evaluation of flash flood disaster is an important element task of this project. According to analyze the characteristics of rainstorm, basic parameters of the small watershed, social economy, the historical flood, etc. in the mountain areas possibly occur flash flood, this task aims to assess the flood control capacity of villages, towns and cities along the mountain rivers, declare the distribution of population and housings in the areas with different hazard grades, estimate the early-warning indexes such as rainfall and water level and their threshold values. The results can support and guide the warning system, forecasting, regional planning, land use and emergency response, and so on for flash flood disaster prevention. This paper will use a case of two small watersheds in Lingbao County of Henan Province to introduce the conceptual framework, methodology, process, key technology, rationality analysis and results of analysis and evaluation on flash flood disaster. [ABSTRACT FROM AUTHOR]

• We propose an LSTM-based approach for large-scale flash flood warning. • This approach was demonstrated in the mountainous and hilly areas of China. • This approach achieved a hit rate of 0.84 without using commercially sensitive data. • The proposed approach provides a more accurate result than FFG and RTI methods. Flash flood warning (FFW) systems play a fundamental role in flood hazard prevention and mitigation. In this study, we propose the first deep learning-based approach for large-scale FFW and demonstrate the application of this approach to mountainous and hilly areas of China. Specifically, the time series of precipitation before flash floods and three spatial features (maximum daily precipitation, curve number, and slope) are selected as predictors. A long short-term memory (LSTM)-based approach is adopted to predict the occurrence of flash floods, and we compare this approach with two widely used FFW methods, namely the rainfall triggering index (RTI) and flash flood guidance (FFG). The results demonstrate the following: (1) The LSTM-based approach provided a reliable FFW 1 day ahead with a hit rate (HR) of 0.84 and false alarm rate (FAR) of 0.09. It demonstrated moderate warning performance 2 days before flash floods, with an HR of 0.66 and FAR of 0.21. (2) The LSTM-based approach outperformed the benchmark RTI and FFG methods, achieving the highest critical success index (CSI) of 0.77. The FFG also provided satisfactory performance, with a CSI of 0.71, and the RTI demonstrated the lowest performance (CSI = 0.68). (3) The LSTM-based approach provides better results (CSI = 0.75) than RTI (CSI = 0.68) when only the time series of precipitation is used for prediction. The performance of the LSTM-based approach can be improved by considering the spatial features and a long time series of precipitation during model development. (4) The proposed approach did not exacerbate the effect of precipitation uncertainty on the flash flood warning; and we suggest using ensemble results for FFW to reduce the uncertainty caused by small or unbalanced learning samples. We conclude that the proposed approach is a valid method for large-scale FFW without using commercially sensitive observations, and can improve the capabilities of flood disaster mitigation, particularly in ungauged areas. [ABSTRACT FROM AUTHOR]

The spatiotemporal evolution of vegetation and its influencing factors can be used to explore the relationships among vegetation, climate change, and human activities, which are of great importance for guiding scientific management of regional ecological environments. In recent years, remote sensing technology has been widely used in dynamic monitoring of vegetation. In this study, the normalized difference vegetation index (NDVI) and standardized precipitation–evapotranspiration index (SPEI) from 1998 to 2017 were used to study the spatiotemporal variation of NDVI in China. The influences of climate change and human activities on NDVI variation were investigated based on the Mann–Kendall test, correlation analysis, and other methods. The results show that the growth rate of NDVI in China was 0.003 year−1. Regions with improved and degraded vegetation accounted for 71.02% and 22.97% of the national territorial area, respectively. The SPEI decreased in 60.08% of the area and exhibited an insignificant drought trend overall. Human activities affected the vegetation cover in the directions of both destruction and restoration. As the elevation and slope increased, the correlation between NDVI and SPEI gradually increased, whereas the impact of human activities on vegetation decreased. Further studies should focus on vegetation changes in the Continental Basin, Southwest Rivers, and Liaohe River Basin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sixteen phenylpropanoids (40 μM) exhibited strong inhibitory effects on NO production in TNF-α-stimulated MH7A cells. • Pinoresinol and dendrocoumarin A were the most effective substances from the extract of Dendropanax dentiger roots against RA through inhibiting NF-kB, Akt and JNK signaling pathways. • Pinoresinol and dendrocoumarin A may be promising candidates for anti-RA treatment. The root of Dendropanax dentiger (Harms) Merr. has been used for centuries as an empirical treatment for rheumatoid arthritis (RA) in China without scientific validation. In our recent study, nineteen phenylpropanoids (1 – 19) with cyclooxygenase-2 inhibitory activities from the ethanol extract of D. dentiger roots, indicated to have a potential anti-RA effect. This study, evaluated the anti-RA effect of 19 phenylpropanoids on tumor necrosis factor (TNF)-α induced inflammation in MH7A cells and clarified their underlying mechanisms. As a result, 16 compounds remarkably suppressed nitric oxide (NO) production at a concentration of 40 μM in TNF-α-induced MH7A cells. Among them, pinoresinol (12) and dendrocoumarin A (1) were the most effective substances, which showed significant inhibitory effect on NO production, with IC 50 values of 6.25 ± 0.42 and 7.87 ± 0.67 μM, respectively. Furthermore, pinoresinol and dendrocoumarin A remarkably decreased the levels of interleukin (IL)-2, 6, 8, and interferon-gamma (IFN-γ), as well as prominently reduced the phosphorylation protein levels of nuclear factor kappa B (NF-κB) p65, I-kappa-B-alpha (IkBα), protein kinase B (Akt), and c-Jun N-terminal kinase (JNK) by Western blot analysis. Taken together, our findings suggest that pinoresinol and dendrocoumarin A may offer new and safe anti-RA candidates by inhibiting NF-kB, Akt and JNK signaling pathways. [ABSTRACT FROM AUTHOR]

Due to easily causing severe disasters in mountainous areas, typhoon rainfall forecast with numerical weather prediction (NWP) system plays an important role for meteorological and hydrological use. In order to investigate the applicability of physical parameterisations for typhoon rainstorms, thirty-six physical parameterisation combinations are designed by three microphysics (Lin, WSM6 and WDM6), three pairs of longwave/shortwave radiations (RRTM/Dudhia, RRTMG/RRTMG and CAM/CAM) and four cumulus parameterisations (KF, BMJ, GD and Grell 3D). The Weather Research and Forecasting (WRF) model is used to simulate the three representative typhoon storm events occurred in southeast coast of China and the rainfall simulations in Meixi catchment are evaluated. Not only for the individual parameterisation but also for the parameterisation combination, WSM6, RRTMG/RRTMG and KF outperform the other physical parameterisation as a whole. The WRF model has poor capability in simulating the rainfall caused by strong convection, and the storm events with uneven distributed rainfall tend to have worse rainfall simulation in space and time dimensions. The findings provide references for choosing the physical parameterisation, which can help to obtain relatively reliable typhoon rainfall forecast and flood warning in catchment scale. The shortage of the NWP system and the solution for improve the rainfall simulation are also put forward. • Thirty-six physical parameterization combinations are evaluated. • WSM6, RRTMG/RRTMG and KF outperform other parameterizations. • Rainfall with strong convection is difficult to be reproduced. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease without effective and beneficial drugs. Many traditional folk medicines have been proven to be effective in treating RA. Among these, the root of Pterospermum heterophyllum Hance has been widely used as a traditional remedy against RA in China, but there is no scientific basis yet. The aim of this study was to investigate for the first time the chemical compositions and therapeutic effect of P. heterophyllum on adjuvant-induced arthritis (AIA) model in rats. 73 compounds were identified from P. heterophyllum based on ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-qTOF-MS/MS), and flavonoids may be partly responsible for the major anti-arthritic effect. In parallel, the P. heterophyllum extract at 160, 320, and 640 mg/kg/day were orally administered to rats for 22 days after post-administration adjuvant. The results showed that P. heterophyllum remarkably ameliorated histological lesions of the knee joint, increased body weight growth, decreased arthritis score, reduced thymus and spleen indices in model rats. Moreover, P. heterophyllum treatment persuasively downregulated the levels of rheumatoid factor (RF), C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-6, IL-17, cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) and matrix metalloproteinase-2 (MMP-2), and observably upregulated IL-4 and IL-10 levels in model rats. These findings suggest that P. heterophyllum has a prominent anti-RA effect on AIA rats by modulating the inflammatory responses, and supports the traditional folk use of this plant. [ABSTRACT FROM AUTHOR]

A Gram-staining-negative, facultative aerobic, motile strain, designated strain ZSDE20 T , was isolated from the surface seawater of Qingdao offshore. Phylogenetic analysis of the 16S rRNA gene of strain ZSDE20 T , affiliated it to the genus Photobacterium. It was closely related to Photobacterium lutimaris DF-42  T (98.92% 16S rRNA gene sequence similarity). Growth occurred at 4-28ºC (optimum 28ºC), pH 1.0-7.0 (optimum 7.0) and in the presence of 1-7% (w/v) NaCl (optimum 3%). The dominant fatty acids were summed feature 3 (C16:1 ω7c or/and C16:1 ω6c, 34.23%), summed feature 8 (C18:1 ω7c and C18:1 ω6c, 10.36%) and C16:0 (20.05%). The polar lipids of strain ZSDE20 T comprised phosphatidylethanolamine, phosphatidylcholine, lyso-phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol dimannoside, phosphatidylinositol mannosides and two unknown lipids. The major respiratory quinone was ubiquinone-8 (Q-8). The DNA G + C content of strain ZSDE20 T was 45.6 mol%. Average nucleotide identity (ANI) values between ZSDE20 T and its reference species were lower than the threshold for species delineation (95-96%); in silico DNA-DNA hybridization further showed that strain ZSDE20 T had less than 70% similarity to its relatives. Based on the polyphasic evidences, strain ZSDE20 T is proposed as representing a novel species of the genus Photobacterium, for which the name Photobacterium pectinilyticum sp. nov. is proposed. The type strain is ZSDE20 T (= MCCC 1K06283 T  = KCTC 82885  T )., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Neoadjuvant chemoimmunotherapy has offered novel therapeutic options for patients with locally advanced oesophageal squamous cell carcinoma (ESCC). Depicting the landscape of genomic and immune profiles is critical in predicting therapeutic responses., Methods: We integrated whole-exome sequencing, single-cell RNA sequencing, and immunofluorescence data of ESCC samples from 24 patients who received neoadjuvant treatment with PD-1 inhibitors plus paclitaxel and platinum-based chemotherapy to identify correlations with therapeutic responses., Findings: An elevation of small insertions and deletions was observed in responders. DNA mismatch repair (MMR) pathway alternations were highly frequent in patients with optimal responses and correlated with tumour infiltrating lymphocytes (TILs). Among the TILs in ESCC, dichotomous developing trajectories of B cells were identified, with one lineage differentiating towards LMO2 + germinal centre B cells and another lineage differentiating towards CD55 + memory B cells. While LMO2 + germinal centre B cells were enriched in responding tumours, CD55 + memory B cells were found to correlate with inferior responses to combination therapy, exhibiting immune-regulating features and impeding the cytotoxicity of CD8 + T cells. The comprehensive evaluation of transcriptomic B cell lineage features was validated to predict responses to immunotherapy in patients with cancer., Interpretation: This comprehensive evaluation of tumour MMR pathway alternations and intra-tumoural B cell features will help to improve the selection and management of patients with ESCC to receive neoadjuvant chemoimmunotherapy., Funding: National Science Foundation of China (82373371, 82330053), Eastern Scholar Program at Shanghai Institutions of Higher Learning, National Science and Technology Major Project of China (2023YFA1800204, 2020YFC2008402), and Science and Technology Commission of Shanghai Municipality (22ZR1410700, 20ZR1410800)., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

A Gram-straining-negative, facultatively anaerobic, motile by means of a polar flagellum and rod-shaped marine bacterium, designated S4M6 T , was isolated from surface seawater collected in Dongshan Bay (Fujian, PR China). Phylogenetic analysis based on 16S rRNA genes, phylogenomic analysis of single-copy gene families and whole genome data indicated that S4M6 T represented a member of the genus Vibrio . The closest phylogenetic relatives of S4M6 T were Vibrio marisflavi CGMCC 1.8994 T (97.8 % 16S rRNA gene sequence pairwise similarity), Vibrio variabilis LMG 25438 T (96.9 %), Vibrio gangliei SZDIS-1 T (96.2 %) and Vibrio aestivus M22 T (96.1 %). The growth of S4M6 T occurred at 15-35 °C (optimum 28 °C), pH 4.0-9.0 (optimum 5.0-7.0) and in the presence of 2-5 % (w/v) NaCl (optimum 3 %). The predominant fatty acids (>10 %) are C 16 : 0 , summed feature 3 (C 16 : 1 ω7 c and/or C 16 :   1 ω6c) and summed feature 8 (C 18 : 1 ω7 c and/or C 18 :   1 ω6 c ). The DNA G+C content of the assembled genomic sequences was 43.4 % for S4M6 T . Average nucleotide identity (ANI) values between S4M6 T and the reference species were lower than the threshold for species delineation (95-96 %); in silico DNA-DNA hybridization further indicated that S4M6 T had less than 70 % similarity to its relatives. On the basis of the polyphasic evidence, strain S4M6 T is proposed to represent a novel species of the genus Vibrio , for which the name Vibrio sinus sp. nov. is proposed. The type strain is S4M6 T (= KCTC 92312 T = MCCC 1K06167 T ).

Two Gram-staining-negative, facultatively anaerobic, motile, short clavate and flagellated marine bacteria, designated strains BEI233 T and LJC006 T , were isolated from the East China Sea. On the basis of the results of 16S rRNA gene sequencing and multilocus sequence analysis, BEI233 T and LJC006 T should be assigned to the genus Vibrio . The closest phylogenetic relatives of BEI233 T are Vibrio scophthalmi LMG 19158 T (98.7 % 16S rRNA gene sequence pairwise similarity), Vibrio ichthyoenteri DSM 14397 T (98.5 %), Vibrio renipiscarius KCTC 42287 T (97.7 %), Vibrio aestuarianus ATCC 35048 T (97.3 %) and Vibrio thalassae MD16 T (96.5 %), whereas for LJC006 T they were Vibrio furnissii CAIM 518 T (97.1 %), Vibrio fluvialis LMG 7894 T (97.0%), Vibrio tritonius JCM 16456 T (96.9 %) and Vibrio xuii LMG 21346 T (96.1 %). The growth of BEI233 T occurred at 10-37 °C, pH 5.0-8.0 and with 1-7 % (w/v) NaCl, while the growth of LJC006 T occurred at 10-37 °C, pH 6.0-9.0, and 0-8 % (w/v) NaCl. The predominant fatty acids (>10 %) were summed feature 3 (C 16 : 1 ω7 c or/and C 16 : 1 ω6 c ), C 16 : 0 and summed feature 8 (C 18 : 1 ω7 c or/and C 18 : 1 ω6 c ), with different proportions. The DNA G+C contents of BEI233 T and LJC006 T are 42.41 mol% and 41.88 mol%, respectively. On the basis of the results of polyphasic analysis, BEI233 T and LJC006 T are considered to represent novel species of the genus Vibrio, for which the names Vibrio sinensis sp. nov. and Vibrio viridaestus sp. nov. are proposed. The type strains are BEI233 T (=JCM 32692 T =KCTC 62618 T ) and LJC006 T (=JCM 32693 T =KCTC 62620 T ), respectively.

Two Gram-stain-negative, catalase- and oxidase-positive, facultative anaerobic and rod-shaped motile bacteria, designated strains BEI176 T and BEI207 T , were isolated from seawater collected in the East China Sea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains BEI176 T and BEI207 T belonged to the genus Vibrio and were closely related to each other with 98.18 % similarity. The closest phylogenetic relatives of strain BEI176 T were Vibrio alginolyticus LMG 4409 T (98.85 %) and Vibrio campbellii LMG 11216 T (98.81 %), whereas the closest relative of strain BEI207 T was Vibrio hepatarius LMG 20362 T (98.64 %). The two strains showed growth at different conditions; while strain BEI176 T grew at 16-37 °C, pH 5.0-9.5 and 0-7.0 % (w/v) NaCl, the growth of strain BEI207 T occurred at 10-37 °C, pH 6.0-9.5 and 1.0-7.0 % (w/v) NaCl. Both strains shared the same major fatty acid components of summed feature 3 (C 16 : 1 ω7 c or C 16 : 1 ω6 c ), C 16 : 0 and summed feature 8 (C 18 : 1 ω6 c or C 18 : 1 ω7 c ). The DNA G+C contents of the assembled genomic sequences were 44.73 and 45.06 mol% for strains BEI176 T and BEI207 T , respectively. Average nucleotide identity values between the two strains and their reference species were lower than the threshold for species delineation (95-96 %); in silico DNA-DNA hybridization further showed that the two strains had less than 70 % similarity to their relatives. Therefore, two novel Vibrio species are proposed to accommodate them: Vibrioouci sp. nov. (type strain, BEI176 T =MCCC 1K03515 T =JCM 32690 T = KCTC 62616 T ) and Vibrioaquaticus sp. nov. (type strain, BEI207 T =MCCC 1K03516 T =JCM 32691 T =KCTC 62617 T ).

Objective: To investigate 4 populations of 80 samples of Vitex trifolia var. simplicifolia collected from Shandong and Jiangxi province and analyze their intraspecies genetic variance., Method: Inter-simple sequence repeat (ISSR) technique was applied for the study., Result: Fifteen specific and stable primers were selected from 100 primers. A total of 129 sites were generated, and 115 of them (89.15%) were polymorphic. The data analyzed by PopGene demonstrated that the average polymorphic site percentage among the four populations was 71.89%. The average Shannon's information index was 0. 220 4. According to cluster analysis and the law of geographic variation, the populations were classified into two large groups: the Shandong group and the Jiangxi group., Conclusion: These results will provide the information for protection and utilization of V. trifolia var. simplicifolia and also further data for the study of genetic variation and species differentiation of V. trifolia var. simplicifolia.