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【Objective】 The inverted siphon tunnel in big long-distance open channel spanning across a river is a critical hydraulic infrastructure. Investigating the mechanisms and strategies for addressing the unsteady flow during transition from the pressurized tunnel to the non-pressurized diffusion section of the open channel is essential to safeguarding water delivery and optimizing flow capacity. 【Method】 Using the principles of flow similarity and boundary layer control theory, this study focuses on the transition section at a large water transfer siphon outlet. Through hydraulic model testing, it examines the boundary layer separation, derived backflow interference, mainstream instability, and flow fluctuations in the diffusion section. We also investigate three additional turbulent effects resulting from unfavorable flow patterns. 【Result】 ① The boundary layer separation in the diffusion section leads to the entrainment of a significant number of vortices by the main flow, resulting in an increased energy consumption and the superposition of derived waves. These phenomena disrupt the smooth flow in the diffusion section. ②Introducing diversion piers in the diffusion section effectively suppresses boundary layer separation, eliminates vortex shedding, and mitigates side backflow in the confluence area. This leads to a substantial improvement in wave dissipation, reducing wave intensity at the end of the diffusion section from 1.11 to 0.2 m. Furthermore, it straightens the flow path within the diffusion section. 【Conclusion】 Installing diversion piers in the diffusion section is highly effective in eliminating vorticity and reducing wave interference. Specifically, B-type diversion piers prove to be superior in optimizing flow patterns and reducing energy consumption while ensuring a well-balanced flow velocity distribution. These research findings hold significant practical value for design and renovation of large-scale water transfer projects.

BackgroundAcute liver failure (ALF) is a complicated clinical syndrome associated with high mortality, with liver transplantation as the only treatment option. Treatment of mesenchymal stem cells has shown a potential therapeutic option for acute liver failure. However, the lack of random clinical trials and large non-human primate studies makes it necessary to assess the efficacy and safety in the clinic.MethodsWe treated the monkeys with peripheral delivery of human umbilical MSCs (hUC-MSCs) and investigated the role of hUC-MSCs in modulating the progress of acute liver failure.ResultsThe use of early peripheral infusion of human umbilical cord MSC infusion did not improve liver regeneration or modulate adaptive immunity. However, it significantly suppressed the hepatic aggregation and maturation of circulating monocytes and their IL-6 secretion, greatly improving liver histology, systemic homeostasis, and survival.ConclusionsOur study reveals the critical role of monocyte-derived IL-6 in initiating and accelerating acute liver failure and hUC-MSC treatment can disrupt the development of the inflammatory cascade by inhibiting monocyte activation. Early hUC-MSC treatment disrupts the development of the inflammatory cascade, indicating a potential clinical solution for acute liver failure.

Radar beam blockage is an important error source that affects the quality of weather radar data. The S-band dual-polarization radar in Guangzhou has multi-azimuth occlusion at low elevation and is partially occluded at high elevation. Based on deep learning methods such as convolutional neural network, two echo filling networks, i.e., VEF(vertical echo-filling) and HEF(horizontal echo-filling) are constructed. Based on this architecture, echoes from the unblocked area are used to construct training datasets and fill the reflectivity ZH and differential reflectivity ZDR in the occlusion area. For the area with only 0.5° elevation occlusion, multi-modal modeling is carried out based on VEF architecture by using 3D data from multiple upper elevations, radial directions and gates. Considering that the radar beam broadens with distance and to avoid the influence of the melting layer, the radar beam is divided into four sections according to the oblique distance of 0.5° elevation, and the vertical echo-filling model is trained respectively. For the area with high occlusion elevation, multi-mode modeling is carried out based on HEF architecture using the data of multiple adjacent radial directions and gates with the same elevation. According to the number of occlusion radial, two types of horizontal echo-filling models, three radials echo-filling model and five radials echo-filling model are constructed respectively. Finally, the models are evaluated by three cases and three indicators:Explained variance, mean absolute error and correlation coefficient. The maximum explained variance of ZH vertical echo-filling model is 0.91, the minimum mean absolute error is 1.72 dB, and the maximum correlation coefficient is 0.96. The maximum explained variance of ZDR vertical echo-filling model is 0.87, the minimum mean absolute error is 0.12 dB, and the maximum correlation coefficient is 0.92. The maximum explained variance of ZH horizontal fill model is 0.92, the minimum mean absolute error is 1.69 dB, and the maximum correlation coefficient is 0.96. The maximum explained variance of ZDR horizontal echo-filling model is 0.92, the minimum mean absolute error is 0.12 dB, and the maximum correlation coefficient is 0.96. The deep learning echo-filling model can be used to correct the echoes of Guangzhou S-band dual-polarization radar occlusion area effectively, and the quality of weather radar data is improved.

MYB-related transcription factors (TFs) subfamily is a subfamily of MYB TFs, which are mainly involved in plant secondary metabolism, growth and development, and stress response. To explore the function of MYB-related subfamily genes in Rosa chinensis, this study systematically analyzed characters of the MYB-related subfamily members in R. chinensis with bioinformatic analysis using the genomic data of R. chinensis and investigated their expression characteristics using quantitative real-time PCR (qRT-PCR). The results show that 100 MYB-related proteins were identified in R. chinensis. Proteins are mainly found in the nucleus. Chromosome localization revealed that all MYB-related genes are mapped to seven chromosomes and are distributed in clusters. Collinear analysis shows that 13 pairs of MYB-related genes had a collinear relationship, indicating R. chinensis may have evolved its MYB-related subfamily gene through fragment duplication. The analysis of motifs and conserved domains shows that Motif 3 is the most conserved motif. There are numerous ABA and MeJA response elements in MYB-related genes. ABA and MeJA treatments significantly shortened the vase life of R. chinensis, while the flower diameter on day 3 was the largest, suggesting that ABA and MeJA might induce MYB-related gene expression during cut flower senescence. The expression of MYB-related genes is tissue specific, most of which show the highest expression levels in petals. Notably, among six plant growth regulator treatments, ABA treatment significantly increased RcMYB002 expression in R. chinensis, suggesting that RcMYB002 may be a crucial gene for ABA response. This study provides a reference for further research on the function of MYB-related genes in R. chinensis. [ABSTRACT FROM AUTHOR]

Objective: Cardiovascular complications associated with COVID‐19 are being increasingly recognized. They include potential long‐term effects on the heart, although how these complications manifest in patients with stroke who are already vulnerable to cardiovascular issues is lacking. This study addressed this gap by investigating the influence of SARS‐CoV‐2 infection on cardiac hemodynamic changes in inpatients with stroke, thereby providing valuable insights into the management of cardiac complications in this population. Methods: This retrospective cohort study enrolled inpatients with stroke who did or did not experience SARS‐CoV‐2 infection in Shenzhen Second People's Hospital. Clinical information, hemodynamics data, serum myocardial enzyme levels, functional levels, including Barthel index, and Longshi scale assessment (bedridden, domestic, and community) were extracted from clinical records. An independent sample t‐test and the Mann–Whitney U test were used for comparison between groups. Multiple logistic regression analysis was used to identify indicators associated with decline in cardiac function in patients with stroke post‐COVID‐19. Results: Eighty‐three patients with stroke (average age of 66.0 ± 15.5 years) were recruited (42 patients in the study group and 41 in the control group). No significant difference in general characteristics was observed between the groups. The ejection fraction (EF, 56.45 ± 12.46 vs. 47.64 ± 14.76, p = 0.04) was decreased, and the end‐diastolic volume (EDV, 142.74 ± 80.00 vs. 193.34 ± 140.17, p = 0.001) was increased significantly in patients infected with SARS‐CoV‐2 compared with the noninfected participants. SARS‐CoV‐2 infection was an independent risk factor for EF (−10%) decrease (OR: 5.205, 95% CI: 1.621–16.720, p = 0.006). The risk of cardiac function decline among bedridden infected patients was 15.43 times higher than that of uninfected nonbedridden patients (OR: 15.430, 95% CI: 1.402–169.805, p = 0.025). Conclusion: Patients who are bedridden after stroke face a higher potential risk of cardiac hemodynamic impairment following SARS‐CoV‐2 infection, emphasizing the need for meticulous hemodynamic monitoring during treatment and rehabilitation of these patients to prevent any potential cardiovascular complications. Trial Registration: ClinicalTrials.gov identifier: ChiCTR2300071376. [ABSTRACT FROM AUTHOR]

【Background】 Floodplain is the ecological cradle of alluvial rive to provide a buffer to flooding. Rivers naturally function to transport runoff and sediment, making the river have the double section characteristics of river trough and beach to meet the needs of water and sediment transportation in different periods. There are also villages in the floodplain of many rivers. There will inevitably be some contradictions between the needs of human activities (such as agricultural irrigation, transportation and social development) and river functions (ecology, flood and sediment transportation). If there is no scientific coordination between the two aspects, it will lead to mutual restriction affecting the ecological health of the river as well as the Sustainable high-quality development of the beach area society. It has become an important challenge for river managers to plan traffic routes in wide floodplain areas with less environmental impact. In order to implement the protection of river health in river project construction, the characteristics of alluvial river flood must be understood under the influence of human activity. 【Objective】 Taking advantage of the vast river floodplain to conduct the appropriate development and construction, it would be helpful to promote the high-quality development of the river basin. Learning more about the flood characteristics of alluvial rivers under the influence of human activities, and proposing a solution scheme to realize the coordination of floodplain engineering construction and river safety flood discharge, would contribute to practicing the protection of river health in constructing the river engineering. 【Method】 Taking a proposed eco-tourism greenway in the wide floodplain area of an alluvial river as an example, using the comprehensive research method involving historical evolution analysis, riverbed scouring-depositing prediction and hydrodynamic numerical simulation, the flood characteristics of the engineering reach, the law of river course evolution, the riverbed adjustment factors at the lower reaches of the reservoir were analyzed. The treatment model for predicting the riverbed boundary and the equivalent resistance of the river engineering were studied. By means of two-dimensional flood numerical simulation, the flood characteristics of the river section involved in the greenway and the influence of the route on the flow field during the flood discharge period were also analyzed. 【Result】 Firstly, the simulation shows the free swing of the mainstream is restricted by the regulation projects, and the river regime in flood period remains unchanged. Secondly, the proposed greenway is far away from the main channel and the routing is in parallel with the channel, which make the water blocking ratio of the flow area in the beach area less than 2.6%, and the local backwater caused by road construction limited to 0.058 m. 【Conclusion】 The arrangement of the proposed greenway is suggested to be routed along the river and located in high beach. Through scientific planning of routes and project layout, the impact of the project on the propagation of river floods can be minimized, and the coordinated relationship between the river flood discharge safety and the beach area development can be satisfied.

Acute liver failure (ALF) is associated with high mortality, and a poor understanding of the underlying pathophysiology has resulted in a lack of effective treatments so far. Here, using an amatoxin-induced rhesus monkey model of ALF, we panoramically revealed the cellular and molecular events that lead to the development of ALF. The challenged monkeys with toxins underwent a typical course of ALF including severe hepatic injury, systemic inflammation and eventual death. Adaptive immune was not noticeably disturbed throughout the progress of ALF. A systematic examination of serum factors and cytokines revealed that IL-6 increase was the most rapid and drastic. Interestingly, we found that IL-6 was mainly produced by circulating monocytes. Furthermore, ablation of monocyte-derived IL-6 in mice decreased liver injury and systemic inflammation following chemical injection. Our findings reveal a critical role of circulating monocytes in initiating and accelerating ALF, indicating a potential therapeutic target in clinical treatment for ALF.