Valve Structure Research Articles

Molecular phylogeny, morphology and distribution of Amphitetras antediluviana Ehrenberg from the Black Sea and the Sea of Azov

The intriguing large-celled species of Amphitetras antediluviana Ehrenberg was originally described as a fossil species (Ehrenberg, 1840), but later noted in a living state in various regions of the World ocean. Our recent studies revealed that the species has been found for the last decade in significant numbers in many habitats along the coast of the Azov-Black Sea basin. Two strains—the large valves from Laspi Bay, the Black Sea (BL-5_12092019) and the small valves from the Sea of Azov (AZ-12_24122019)—were isolated and analyzed using light and scanning electron microscopy along with molecular-genetic investigation. Specimens of the two populations differ in valve sizes and structure, however, their belonging to the same species was confirmed with the help of molecular analysis. Taxonomic positions of the strains of A. antediluviana isolated from two marine waterbodies were clarified. In addition, we provided a detailed morphological diagnosis of the species with a description of the valve ultrastructure and its elements, as well as geographical distribution and taxonomic history.

Finite Element Analysis and Computational Fluid Dynamics for the Flow Control of a Non-Return Multi-Door Reflux Valve

This paper presents a comprehensive analysis of a multi-door check valve using computational fluid dynamics (CFD) and finite element analysis (FEA) to evaluate flow performance under pressure test conditions, with an emphasis on its ability to prevent backflow. Check valves are essential components in various industries, ensuring fluid flow in one direction only while preventing reverse flow. The non-return multi-door reflux valve is increasingly preferred due to its superior backflow prevention, fluid control, and effective flow regulation. Rigorous testing under varying pressure conditions is essential to ensure that these valves perform optimally. This study uses CFD and FEA simulations to evaluate the structural integrity and flow characteristics of the valve, including pressure drop, flow velocity, backflow prevention effectiveness, and flow coefficient. A high-fidelity 3D model was created to simulate the valve’s behavior under various conditions, analyzing the effects of parameters such as the number of doors, their orientation, geometry, and operating conditions. The CFD results demonstrated a significant reduction in backflow and pressure drop across the valve. However, localized turbulence and flow separation near the valve doors, particularly under partially open conditions, have raised concerns about potential wear. The velocity profiles indicated a uniform distribution at full opening with laminar velocity profiles and minimal resistance to flow. The results of the FEA showed that the stresses induced by the fluid forces were below critical levels, with the highest stress concentrations observed around the hinge points of the valve doors. Although the valve structure remained intact under normal operating conditions, some areas may have required reinforcement to ensure long-term durability. Combined CFD and FEA analyses demonstrated that the valve effectively preserves system integrity, prevents backflow, and maintains consistent performance under various pressure and flow conditions. These findings provide valuable insights into design improvements, performance optimization, and enhancing the efficiency and reliability of reflux valve systems in industrial applications.

Comparative analysis of performance of different types of Tesla valves

Abstract The Tesla valve is a valve with no moving parts. Its special configuration also allows the pressure drop of fluid passing through the Tesla valve from the reverse inlet to be much greater than the pressure drop of fluid passing through the Tesla valve from the forward inlet. Therefore, the Tesla valve has a certain degree of single pilot connectivity and pressure reduction capability. This article selected 8 common types of Tesla valves, By using numerical calculation method through Fluent simulation, the differences of resistance coefficient, pressure drop and Di value of 8 types of single-stage Tesla valves under three different working conditions were compared. In order to explore the performance of 8 kinds of Tesla valves under the three working conditions. At the same time, the relationship between the flow state and the structure of each part of the fluid before and after passing through the distributary pipe is analyzed. The simulation results show that due to the different structure of various Tesla valves, the flow rate, pressure and turbulent kinetic energy of the fluid inside the valve also have different changes. At the same time, there are many similarities in the flow state of some Tesla valves with similar structural types. Finally, according to the calculation results, the advantages and disadvantages of various types of Tesla valves and their applications are analyzed.

Principle and pressure loss experiment of electro-hydraulic slide-rotary direction valve in single-pump and multi-motor hydraulic system

To better realize direction control of the single-pump double-motor hydraulic system and simplify the system, structure and principle of a six-position six-way direction control valve was proposed, which the valve spool has two motion modes: sliding and rotating. Using this valve, the inner and outer motors can work independently and simultaneously. The pressure loss of the valve was tested by building a transmission system, and the experiment results were compared with theoretical analysis. The results show that the performance of the valve working in left and right positions is better than that in meso-position, and the maximum pressure loss occurred in meso-position. Under the rated flow, the maximum pressure loss is 0.331 MPa. Then the characteristic curve of flow-pressure loss and the relationship of pressure loss among oil ports are obtained. In the same conditions, except that the oil inlet pressure loss in the meso-position is greater than the oil outlet pressure loss, the oil inlet pressure loss in the left and right positions are less than the oil outlet pressure loss, the pressure loss in the forward position is less than the pressure loss in the reverse position. The experiment verifies the correctness and feasibility of the structure and principle.

Left atrioventricular valve regurgitation repair with concomitant outflow obstruction release on repaired atrioventricular septal defect case

BackgroundLeft ventricular outflow tract stenosis and atrioventricular valve regurgitation are often problems encountered in adulthood after complete atrioventricular septal defect repair. The surgical approach and indications for managing long-term outcomes such as left atrioventricular valve regurgitation and left ventricular outflow tract stenosis after complete atrioventricular septal defect repair have been discussed.Case presentationA 23-year-old woman with intellectual disability was diagnosed with complete atrioventricular septal defect and underwent two-patch repair without cleft closure in childhood. Follow-up examination in adulthood demonstrated moderate left-sided atrioventricular valve regurgitation and left ventricular outflow tract stenosis with a circumferential ridge (peak velocity, 3.7 m/s; pressure gradient, 54 mmHg). Intraoperative findings showed a circumferential ridge under the aortic valve, and we removed the ridge. In addition, a cleft was present at the anterior leaflet, and we completely closed the cleft. Anticoagulation therapy was not initiated, and no embolic complications occurred. Follow-up echocardiography demonstrated no ridge under the aortic valve and only mild-range left AVVR.ConclusionsWe successfully performed surgical treatment without valve replacement or anticoagulation therapy in a patient with poor medical compliance. Delayed reoperation leads to degeneration of the valve structure and makes more difficult to repair. Atrioventricular valve regurgitation should be evaluated in combination with based on the etiology of the regurgitation especially cleft related or not, in addition to the dilatation annulus, cleft size, and depth of the leaflet coaptation depth, and associated other valve diseases.

Analysis of Echocardiography Indicators Depending on the Type of Surgical Correction of the Mitral Valve in Patients with Ischemic Heart Disease

The aim. To study the influence of echocardiography indicators on the choice of surgical intervention on the mitral valve in patients with mitral insufficiency and coronary heart disease. Materials and methods. The study included patients with mitral insufficiency who underwent myocardial revascularization and mitral valve reconstruction (plasty or replacement). The mean age of the study participants was 65.9 ± 4.0 years. The material for analysis was data from the primary medical records: medical history, clinical and instrumental examination data and protocols of operations. The division into study groups was performed retrospectively, according to the mitral valve operation performed: plasty (experimental group) or replacement (control group). Results. We identified the features of the main echocardiographic data that guide the cardiologist when choosing the tactics of surgical correction of the mitral valve. It was established that in patients of the research group, the following was reliably significant: moderate degree of mitral insufficiency (p = 0.02; χ2 = 9.38), decrease in the systolic function of the left ventricle (p = 0.001; χ2 = 10.75); it was found that calcium deposits on the fibrous ring of the mitral valve were insignificant. When analyzing the morphological changes in patients of the experimental group, we found a significantly lower frequency of anterior leaflet prolapse (p = 0.04; χ2 = 4.21) and in general the frequency of all prolapses of any type, while in the control group the frequency of all prolapses was significantly higher (p = 0.04; χ2 = 4.0). In patients of the control group, a significantly higher frequency of akinesis (p = 0.04; χ2 = 4.21) and hypokinesis zones of the posterior-inferior-lateral wall (p = 0.001; χ2 = 19.76) was established, which is an additional sign of involvement of the chordal-muscular apparatus of the mitral valve in pathological process. Conclusions. As a result of the study, echocardiographic differences in the structure of the mitral valve were established, which influenced the selection of the intervention volume. It was found that in patients of the experimental group, the early postoperative mortality and the duration of inpatient treatment were significantly higher than in patients of the control group, which indicates the imperfection of the criteria used by cardiac surgeons when choosing the tactics of surgical correction of the mitral valve in an attempt to perform organ-preserving surgery.

Study on ultrasound diagnosis and pathological anatomy of fetal complex congenital heart disease in the first trimester.

To assess the feasibility of using the stereo-microscope to identify the pathological anatomy of the congenital heart diseases in the first trimester. Fifteen fetuses of 8-12 weeks aborted due to prevent miscarriage failure and 42 fetuses of 11-14 weeks with congenital heart diseases were included in the study, we dissected their hearts through a stereo-microscope, then compared with the prenatal ultrasonographic diagnosis. Using stereomicroscopy, the positive view of the heart and the great arteries, the long axis view of the aortic arch, the inflow tract view of the bottom heart, the semilunar valve view of the bottom heart, and the transverse section of the ventricle were showed contented and obtained satisfactory images, but the structure of atrioventricular valve and venous system had a lower rate of display. The characteristic pathological changes of cardiac inflow and outflow tract can be obtained by dissecting the heart sequential under the stereo-microscopy. However it is often difficult to obtain satisfactory pathological sections for pulmonary venous abnormalities and Ebstein anomaly.

Multi-objective optimization design of low-power-driven, large-flux, and fast-response three-stage valve

Intrinsically safe solenoids drive solenoid valves in coal mining equipment. The low power consumption of these solenoids limits the response time of the solenoid valves. Additionally, the low viscosity and high susceptibility to dust contamination of the emulsion fluid often lead to leakage and sticking of hydraulic valves. This study proposes a low-power-driven, large-flux, fast-response three-stage valve structure with an internal displacement feedback device to address these issues. The critical parameters of the valve were optimized using a novel multi-objective optimization algorithm. A prototype was manufactured based on the obtained parameters and subjected to simulation and experimental verification. The results demonstrate that the valve has an opening time of 21 ms, a closing time of 12 ms, and a maximum flow rate of approximately 225 L/min. The driving power of this structure is less than 1.2 W. By utilizing this valve for hydraulic cylinder control, a positioning accuracy of ± 0.15 mm was achieved. The comparative test results show that the proposed structural control error fluctuation is smaller than that of the 3/4 proportional valve.

The Mitris RESILIA Valve: New Skin for a Proven Design.

By incorporating the best features of the Carpentier-Edwards PERIMOUNT Magna Mitral Ease valve (Edwards Lifesciences Corporation, Irvine, California) and INSPIRIS RESILIA tissue (Edwards Lifesciences Corporation, Irvine, California), the mitris valve inherits the advantages of the remarkable hemodynamic performance of the former and the durability of the latter. In this paper, we will summarize the process that led to the creation of this new valve and report on the first implant's feasibility and first impression. The mitris valve has an overall implantability profile, overlapping the previous generation with no added challenges, but compared to the PERIMOUNT Magna Mitral Ease valve, the mitris valve boasts a more pliable saddle-shaped sewing cuff that is specifically tailored to fit the complex structure of the mitral valve with a lower stent height. This could be particularly beneficial in the context of double-valve replacement, as it may prevent any disturbance to the bioprosthesis located in the aortic position in small annulus. This could also prevent some rare but unpleasant complications such as left ventricle outflow obstruction or rupture of the atrioventricular sulcus. In addition, it could allow for better adherence to the saddle-shaped annulus of the mitral valve with the possibility of less stress (and therefore fibrosis) on the valve tissue, while further reducing the degeneration time. Furthermore, thanks to the possibility of being temporarily adjusted inwards, it is possible to ensure greater implantability compared to the previous generation of Magna Edwards mitral valves. Thanks to INSPIRIS technology, which prevents the generation of free aldehydes that promote oxidation and calcification of pericardial tissue, it is possible to assume that the durability will probably also improve. This reinforces the trustworthiness of the mitris valve.

Development of novel thermal diode inspired by the structure of venous valve

To increase the unidirectional heat transfer capability of a thermal diode, a novel thermal diode with unidirectional movable valves as vapor channel is proposed based on the structure of venous valves. The thermal performance of this bionic thermal diode was experimentally investigated under different working conditions. The results demonstrate that the bionic thermal diode exhibits a high thermal rectification ratio and strong stability. The best thermal rectification ratio is 10.79, with a forward thermal resistance of 0.26 °C/W and a reverse thermal resistance of 2.86 °C/W, at a heating power of 15 W and a filling ratio of 15 %. The temperature distribution indicated that, under the reverse heat transfer mode, the vapor was obstructed at the first valve, leading to the high thermal resistance of thermal diode. Additionally, the effect of inclined angle on the thermal performance of thermal diode was also investigated. This study provides a novel approach for the design of thermal diodes.

NLRP3 inflammasomes as a target for hesperidin and diosmin flavonoids in varicose vein disease and its complications

Varicose vein disease of the lower extremities is an inflammatory disorder with abnormal structure and functional activity of the venous valves, venous walls and cells, as well as with abnormal activity of the infiltrating leukocytes. The abnormally changed varicose vein are characterized by increased venous pressure, blood accumulation and congestion, ischemia, and metabolic and energy turnover derangement, which result in clinical manifestations of complications, such as pain, edema and formation of trophic ulcers. For many years, flavonoids have been used to treat varicose veins. The most effective flavonoids used in varicose vein disease and its complications, are hesperidin and diosmin, as well as their combinations. The review sets forth the state-of-the-art knowledge on the universal inflammatory processes playing a leading role in the pathophysiology of many cardiovascular disorders, including venous ones. In the recent years, it has been found that one of the main causes of inflammation is the formation of intracellular protein complexes (inflammasomes), which both produce a set of proinflammatory cytokines and are responsible for their excretion from the cells. In addition, inflammasomes control the development of regulated necrosis (pyroptosis) that takes part in the process of ulceration. The inflammasome activity can be modified by various mechanisms, of which the gene independent synthesis of the inflammasomal proteins has been recognized as the leading one. It has been shown that flavonoids inhibit the activation of a key factor NF-kappa B and suppress the synthesis of proteins, including NOD-like receptor protein 3 (NLRP3) inflammasome components, decrease the expression of NLRP3 receptor, protein ASC and caspase 1, as well as diminish interleukin 1 beta, interleukin 6 and tumor necrosis factor-alpha expression. Thus, this is the explanation of positive effects observed with the use of hesperidin, diosmin and their combination in clinical practice.

Optimization of isolation valve placement to improve reliability and resilience of water distribution systems

Optimization of isolation valve layout is critical to improve post-failure response restoration of water distribution systems (WDSs) when pipes are damaged. Many studies have been done to optimize isolation valves to improve reliability of WDSs, but less attention has been given to improving the seismic resilience. This paper proposes a multi-objective optimization model for isolation valves placement considering reliability and seismic resilience simultaneously. The newly developed model employs topology-based reliability and resilience indicators to improve efficiency of optimization algorithm by identification of accidental segments and unintended isolation segments using graph theory without hydraulic simulation. The optimization model was applied to two networks with different loop structures. Subsequently, searching trajectory guided by constraints is investigated and performance of isolation valve placements under different valve densities are assessed including topological structure of isolation valves, criticality of segments and isolation valves, and seismic resilience. The results showed that optimal layout of isolation valves obtained through optimization can improve the reliability and resilience of the system. Our novel approach can benefit water utilities that frequently encounter optimal placement of isolation valves to improve the reliability and resilience of WDSs.

Optimization of solenoid valve design for enhanced electromagnetic force in Variable valve timing systems

This paper investigates the impact of structural modifications in solenoid valves on the electromagnetic force characteristics crucial for efficient Variable Valve Timing (VVT) system operation. Utilizing finite element analysis, various hole and slot configurations within solenoid valve components were examined to determine their effect on the electromagnetic forces generated during valve operation. The study focused on base and spool structural parameters, such as the diameter and number of oil drain holes, the size and position of steel ball slots, and variations in structural dimensions. Results from empirical and simulation data reveal significant findings: larger diameters and an increased number of holes tend to reduce electromagnetic forces, while specific configurations can stabilize or enhance these forces. These findings offer critical insights for optimizing solenoid valve designs in VVT systems with the aim of improving performance and reliability. The study establishes a robust theoretical foundation for further empirical research on the multifactorial effects of valve structure on solenoid performance, paving the way for more refined VVT system designs in the automotive industry.

Effect of cross-platform variations on transthoracic echocardiography measurements and clinical diagnosis.

Accurate cardiac chamber quantification is essential for clinical decisions and ideally should be consistent across different echocardiography systems. This study evaluates variations between the Philips EPIQ CVx (version 9.0.3) and Canon Aplio i900 (version 7.0) in measuring cardiac volumes, ventricular function, and valve structures. In this gender-balanced, single-centre study, 40 healthy volunteers (20 females and 20 males) aged 40 years and older (mean age 56.75 ± 11.57 years) were scanned alternately with both systems by the same sonographer using identical settings for both 2D and 4D acquisitions. We compared left ventricular (LV) and right ventricular (RV) volumes using paired t-tests, with significance set at P < 0.05. Correlation and Bland-Altman plots were used for quantities showing significant differences. Two board-certified cardiologists evaluated valve anatomy for each platform. The results showed no significant differences in LV end-systolic volume and LV ejection fraction between platforms. However, LV end-diastolic volume (LVEDV) differed significantly (biplane: P = 0.018; 4D: P = 0.028). Right ventricular (RV) measurements in 4D showed no significant differences, but there were notable disparities in 2D and 4D volumes within each platform (P < 0.01). Significant differences were also found in the LV systolic dyssynchrony index (P = 0.03), LV longitudinal strain (P = 0.04), LV twist (P = 0.004), and LV torsion (P = 0.005). Valve structure assessments varied, with more abnormalities noted on the Philips platform. Although LV and RV volumetric measurements are generally comparable, significant differences in LVEDV, LV strain metrics, and 2D vs. 4D measurements exist. These variations should be considered when using different platforms for patient follow-ups.

Modeling study of the energy separation effect of a control valve structure on a vortex tube

This paper compares the effect of different angles of triangular conical and truncated conical regulating valves on the heat and cold separation of vortex tubes. Numerical simulation and experimental studies show that60° truncated cone regulating valve has better cooling effect. The inlet pressure is in the range of 0.2MPa–0.4 MPa, and the temperature rate change at the cold end of the vortex tube is larger and the numerical change is smaller. Under the same circumstances, the temperature at the cold end of the vortex tube is connected to the area of cold-heat exchange in the tube at the hot end, as well as to the location of the fluid's stagnation point. The vortex merging rate is related to the angle and form of the regulating valve. The experimental data and the simulation results are in relative agreement with each other, with the maximum temperature difference being 4.41 % and the minimum difference being 3.52 %. The numerical simulation is validated by the house validation method using the theoretical model and experimental study, and the change of the angle of the control valve has the same trend with the numerical change of the theoretical model.

Influence of Timing of Stenting on Condition of Venous Valves of Lower Extremities, Frequency and Severity of Development of Post-Thrombotic Disease

INTRODUCTION: Acute deep vein thrombosis (DVT) of the lower extremities (LE) is a life-threatening condition, accompanied by high rates of disability among people of working age. Despite early detection of DVT and the use of recommended antithrombotic therapy, damage to the venous wall, development of valvular reflux and post-thrombotic disease (PTD) inevitably occur. The clinical picture of PTD becomes evident after the development of valve incompetence, which leads to vertical venous reflux and chronic venous hypertension. Timely elimination of venous obstruction can preserve the functionality of valve structures, which will subsequently help reduce the frequency and severity of PTD. AIM: To evaluate the impact of the timing of stenting on the condition of the venous valves, the frequency and severity of the development of PTD in patients with acute DVT of LE. MATERIALS AND METHODS: A prospective interventional study included 49 patients with acute iliofemoral thrombosis. After selective thrombolysis, 25 patients underwent early (within 7 days) and 24 patients underwent delayed (7–30 days) stenting. The incidence and severity of PTD was assessed on the Villalta scale at 3, 6 and 12 months. The effect of treatment on the condition of the venous valves of the LE was assessed at 12 months. On ultrasound examination, reflux was assessed using a scoring system. RESULTS: At 12 months, 2 (8%), 13 (52%), and 10 (40%) patients who underwent delayed stenting, developed severe, moderate, or mild PTD, respectively. In the early stenting group, 6 (25%) patients had no symptoms of PTD, 15 (62.5%) and 3 (12.5%) developed mild and moderate PTD, respectively (p = 0.0005). At 12 months, in the early stenting group, the absence of reflux was recorded in 6 (25%) patients, 4 (17%) patients had valve reflux in the femoral segment, and 14 (58%) in the popliteal segment. In the delayed stenting group, valvular incompetence of both segments was detected in 12 (48%) patients; in 4 (16%) and 9 (36%) patients, the valves of the femoral and popliteal veins were preserved; there were no patients without reflux in both segments. Treatment results for this indicator were better if early stenting was performed (p = 0.0005). CONCLUSION: Early stenting after selective thrombolysis in patients with proximal DVT of LE leads to a decrease in the incidence and severity of symptoms of PTD, and can reduce the incidence of reflux in the deep veins.

Research on the Throttling Performance and Anti-Erosion Structure of Trapezoidal Throttle Orifices

The throttling performance of conventional throttle orifice structures of fluid control valves is very low. Therefore, this paper proposes a novel trapezoidal throttle orifice with excellent throttling performance. The effect of the taper of the throttle orifice on the erosion was researched. Firstly, two schemes of trapezoidal throttle orifice were proposed according to the fluid control valve. Secondly, the excellent throttling performance of the trapezoidal throttle orifice was compared and optimized. Finally, a numerical simulation method of the erosion-resistant ability of the trapezoidal throttle orifice was established. It was found that for the same throttling area, the differential pressure of the trapezoidal orifice was higher than that of the conventional rectangular orifice by about 18.6%. The taper had little effect on the gas production, which increased by only 3.3% during the 10° to 30° change. The maximum erosion was firstly reduced and then increased with increases in the angle from 0 to 25°of the taper. Moreover, the minimum was achieved at about a 20° taper angle. The above research methods provide a theoretical basis for optimizing the size and structure of orifices and the sealing reliability of fluid control valves.

Melt-electrowriting-enabled anisotropic scaffolds loaded with valve interstitial cells for heart valve tissue Engineering

Tissue engineered heart valves (TEHVs) demonstrates the potential for tissue growth and remodel, offering particular benefit for pediatric patients. A significant challenge in designing functional TEHV lies in replicating the anisotropic mechanical properties of native valve leaflets. To establish a biomimetic TEHV model, we employed melt-electrowriting (MEW) technology to fabricate an anisotropic PCL scaffold. By integrating the anisotropic MEW-PCL scaffold with bioactive hydrogels (GelMA/ChsMA), we successfully crafted an elastic scaffold with tunable mechanical properties closely mirroring the structure and mechanical characteristics of natural heart valves. This scaffold not only supports the growth of valvular interstitial cells (VICs) within a 3D culture but also fosters the remodeling of extracellular matrix of VICs. The in vitro experiments demonstrated that the introduction of ChsMA improved the hemocompatibility and endothelialization of TEHV scaffold. The in vivo experiments revealed that, compared to their non-hydrogel counterparts, the PCL-GelMA/ChsMA scaffold, when implanted into SD rats, significantly suppressed immune reactions and calcification. In comparison with the PCL scaffold, the PCL-GelMA/ChsMA scaffold exhibited higher bioactivity and superior biocompatibility. The amalgamation of MEW technology and biomimetic design approaches provides a new paradigm for manufacturing scaffolds with highly controllable microstructures, biocompatibility, and anisotropic mechanical properties required for the fabrication of TEHVs.

Depletion of DAND5 Hinders EMT in Mouse Embryonic Stem Cell Differentiation.

Dand5 encodes a protein that acts as an antagonist to Nodal/TGF-β and Wnt pathways. A mouse knockout (KO) model has shown that this molecule is associated with left-right asymmetry and cardiac development, with its depletion causing heterotaxia and cardiac hyperplasia. This study aimed to investigate the molecular mechanisms affected by the depletion of Dand5. DAND5-KO and wild-type embryoid bodies (EBs) were used to assess genetic expression with RNA sequencing. To complement the expression results that pointed towards differences in epithelial to mesenchymal transition (EMT), we evaluated migration and cell attachment. Lastly, in vivo valve development was investigated, as it was an established model of EMT. DAND5-KO EBs progress faster through differentiation. The differences in expression will lead to differences in the expression of genes involved with Notch and Wnt signalling pathways, as well as changes in the expression of genes encoding membrane proteins. Such changes were accompanied by lower migratory rates in DAND5-KO EBs, as well as higher concentrations of focal adhesions. Within valve development, Dand5 is expressed in the myocardium underlying future valve sites, and its depletion compromises correct valve structure. The DAND5 range of action goes beyond early development. Its absence leads to significantly different expression patterns in vitro and defects in EMT and migration. These results have an in vivo translation in mouse heart valve development. Knowledge regarding the influence of DAND5 in EMT and cell transformation allows further understanding of its role in development, or even in some disease contexts, such as congenital heart defects.

Study on the hydraulic effect of Tesla valve structure on the end roadway of abandoned coal mine pumped storage

The use of abandoned mine for pumped storage has garnered significant attention as a novel energy storage technology. The hydraulics of utilizing underground reservoirs constructed in mine roadways represent a key issue for the application of abandoned mines in pumped storage. This study focuses on the practical situation of the Longdong Coal Mine in Jiangsu Province, China. By employing numerical simulation methods, the research investigates the phenomenon of water wave reflection at the end of the roadway in an abandoned mine pumped storage station, as well as the improvement effect of the Tesla valve structure on the reflected water waves. It was found that under the condition of the hydraulic turbine, the reflected wave height at the end of the roadway could reach 1–1.5 times that before reflection. The Tesla valve structure was found to be an effective means of reducing the water level height at the end of the roadway. The average water level was reduced by 0.55 m and 0.35 m under the two flow rates of 1 m/s and 1.4 m/s, respectively. Under the pump condition, the Tesla valve structure has little obstruction to the reverse flow of water. This study has to a certain extent addressed the issue of excessive wave height from water wave reflections at the end of the roadway, thereby enhancing the operational stability of the abandoned mine pumped storage station.