Unsteady Characteristics of Sediment Transport Under Non-harmonic Waves

AbstractSediment transport under waves is one of the key dynamic processes of coastal sediment motion. Previous studies for this issue are mainly based on linear wave theory and quasi-steady simplification. However, waves in real circumstance are always irregular, generally with a certain degree of asymmetry and/or velocity-leaning especially in shallow water. It is envisaged that sediment movement under non-harmonic waves is different from sinusoidal waves. Based on large eddy simulation of turbulent flows in wave boundary layer, a modified method is proposed to calculate sediment transport rate under non-harmonic waves. It is further used to explore the influences of flow acceleration and the phase lead between the free stream velocity and bed shear stress on sediment transport rate in different phases of one wave cycle for forth-leaning. The net transport rate is found to increase with the degree of asymmetry and velocity-leaning index. Both the acceleration and the phase lead have a great influence on average transport rate in each phase

Effect of rosuvastatin and benazepril on matrix metalloproteinase-2, matrix metalloproteinase-9 and leukotriene B4 of patients with acute myocardial infarction

Purpose: To investigate the effects of rosuvastatin and benazepril on matrix metalloproteinase-2 (MMP-2), MMP-9 and leukotriene B4 (LTB4) of patients with acute myocardial infarction (AMI). Methods: Fifty-six patients with AMI were selected. They were randomly divided into control and study groups. Thirty healthy people were used in the normal group. On the basis of conventional therapy, patients in the control group were given rosuvastatin orally, while those in the study group received rosuvastatin and benazepril orally. The duration of treatment in both groups was 3 months. Serum levels of MMP-2, MMP-9 and LTB4, and incidence of left ventricular remodelling and recurrence of cardiovascular events were determined before and after treatment for both groups. Results: MMP-2, MMP-9 and LTB4 levels in serum were significantly lower for the two groups after treatment, when compared to pre-treatment values, and significantly lower in the study group (p < 0.05). Left ventricular remodelling was lower in the study group than in the control group (p < 0.05). Recurrence of cardiovascular events declined significantly in the study group, relative to control (p > 0.05). Conclusion: Rosuvastatin and benazepril significantly reduce serum levels of MMP-2, MMP-9 and LTB4 in AMI patients, and thus can potentially prevent ventricular remodelling, improve prognosis and reduce recurrence rate

Experiment Study on Local Scouring Depth around Pile Permeable Spur Dikes

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Experimental Study on the Characteristics of Three-Dimensional Flow Structures with Changing Condition in Bifurcation Area

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Experimental Investigation on the Vertical Distribution of Cohesive Sediment Concentration in Weak Dynamical Flow

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Protein-ligand binding representation learning from fine-grained interactions

The binding between proteins and ligands plays a crucial role in the realm of drug discovery. Previous deep learning approaches have shown promising results over traditional computationally intensive methods, but resulting in poor generalization due to limited supervised data. In this paper, we propose to learn protein-ligand binding representation in a self-supervised learning manner. Different from existing pre-training approaches which treat proteins and ligands individually, we emphasize to discern the intricate binding patterns from fine-grained interactions. Specifically, this self-supervised learning problem is formulated as a prediction of the conclusive binding complex structure given a pocket and ligand with a Transformer based interaction module, which naturally emulates the binding process. To ensure the representation of rich binding information, we introduce two pre-training tasks, i.e.~atomic pairwise distance map prediction and mask ligand reconstruction, which comprehensively model the fine-grained interactions from both structure and feature space. Extensive experiments have demonstrated the superiority of our method across various binding tasks, including protein-ligand affinity prediction, virtual screening and protein-ligand docking

Observation of two splitting processes in a partial filament eruption on the sun: the role of breakout reconnection

Partial filament eruptions have often been observed, however, the physical mechanisms that lead to filament splitting are not yet fully understood. In this study, we present a unique event of a partial filament eruption that undergoes two distinct splitting processes. The first process involves vertical splitting and is accompanied by brightenings inside the filament, which may result from internal magentic reconnection within the filament. Following the first splitting process, the filament is separated into an upper part and a lower part. Subsequently, the upper part undergoes a second splitting, which is accompanied by a coronal blowout jet. An extrapolation of the coronal magnetic field reveals a hyperbolic flux tube structure above the filament, indicating the occurrence of breakout reconnection that reduces the constraning field above. Consequently, the filament is lifted up, but at a nonuniform speed. The high-speed part reaches the breakout current sheet to generate the blowout jet, while the low-speed part falls back to the solar surface, resulting in the second splitting. In addition, continuous brightenings are observed along the flare ribbons, suggesting the occurrence of slipping reconnection process. This study presents, for the first time, the unambiguous observation of a two-stage filament splitting process, advancing our understanding of the complex dynamics of solar eruptions.Comment: 12 pages, 8 figure