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Chronic liver disease inevitably progresses to liver cirrhosis, significantly compromising patients' overall survival and quality of life. However, a glimmer of hope emerges with the emergence of mesenchymal stem cells, possessing remarkable abilities for self-renewal, differentiation, and immunomodulation. Leveraging their potential, MSCs have become a focal point in both basic and clinical trials, offering a promising therapeutic avenue to impede fibrosis progression and enhance the life expectancy of individuals battling hepatic cirrhosis. This comprehensive review serves to shed light on the origin of MSCs, the intricate mechanisms underlying cirrhosis treatment, and the cutting-edge advancements in basic and clinical research surrounding MSC-based therapies for liver cirrhosis patients. • Liver cirrhosis is the final stage of many chronic liver diseases. • Mesenchymal stem cells (MSCs) have paracrine, anti-fibrotic, anti-oxidative stress, and immunomodulatory effects, making them a potential treatment option for liver cirrhosis. • MSC-EVs, gene modification, hypoxia, preconditioning with cytokines or growth factors, and combination therapy can enhance the therapeutic effect of MSCs in treating liver cirrhosis. • Clinical trials have proven MSCs' safety and effectiveness in treating liver cirrhosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wave rotor is tried as pressure exchanger for supercritical carbon dioxide. • Unsteady pressure waves in wave rotor does not take high rim speed to do work. • Wave rotor reduce turbomachinery's rotational speed to 8 % and shaft work to 4 % • Wave rotor achieve comparable efficiency and size to turbomachinery. Supercritical carbon dioxide Brayton cycle is emerging as a solution to effective and clean power resources, and the pressure exchanger is a critical part of such cycle. While turbomachinery is the conventional technology of such pressure exchangers, it sustains high shaft work and suffers from especially high rotational speed, which is a key challenge. This work proposed a wave rotor for supercritical carbon dioxide pressure exchanger as an alternative technology of the turbomachinery. Numerical simulation results demonstrate that a wave rotor compresses and expands supercritical carbon dioxide with unsteady pressure waves, so it does not take a high rim speed to do the compression or expansion work like turbomachinery, and a low rotational speed and a low shaft work are available then. According to the design results for a practical compression ratio at 1.93 and a massflow rate at 2.30 kg/s, the wave rotor reduces the rotational speed to 8 % and the shaft work to 4 % of equivalent turbomachines, and the wave rotor has comparable efficiency and size to equivalent turbomachines. This work provides the special advantage and suitability of the wave rotor as a pressure exchanger of the supercritical carbon dioxide Brayton cycle. [ABSTRACT FROM AUTHOR]

Uncertainty aerodynamic design of turbine blades considering the uncertainty impact of geometric variations is significant for the robustness of actual performance. The effect of loading level and its axial distribution on the uncertainty performance of a turbine blade was discussed, and the guidance for the uncertainty loading design was derived. It is demonstrated that the uncertainty impact on the performance is always notable and nonlinear, which is mainly caused by the significant geometric variations in the sensitive areas where the flow state is sensitive to local geometric variations, and the high loading in these areas will aggravate this impact. The nonlinearity means that the damage to performance caused by those harmful geometric variations cannot be offset by the opposite ones, and the loss increases overall. This impact increases parabolically with the increase of loading level, and will be enlarged clearly with an obvious front-loading or aft-loading. Fortunately, modest aft-loading/mid-loading has a great capacity to resist this uncertainty impact, for the relieving of loading in the sensitive areas, and the negative correlation between the profile loss caused by separation and the wake mixing loss. Considering the overall uncertainty performance, a modest mid-loading/aft-loading design is optimal for high/moderate loading levels, respectively. It is proved that reasonable loading distribution can improve the actual uncertainty performance of turbine blades, which provide a powerful support for the consequent uncertainty design. [ABSTRACT FROM AUTHOR]

Developing an efficient and available material for improved cutaneous tissue regeneration is a major challenge in healthcare. Inspired by the concept of moist wound healing, the injectable and self-healing adenine-modified chitosan (AC) hydrogels are designed to significantly accelerate wound healing without the addition of therapeutic drugs. A series of AC derivatives with degree of substitution (DS) ranging from 0.21 to 0.55 were synthesized in aqueous solutions, and the AC hydrogels were prepared by a simple heating/cooling process. AC hydrogels presented good self-healing, low swelling rate capacity, biocompatibility, promote cell proliferation and excellent hemostatic effect. The hydrogels displayed excellent antibacterial activities against gram-negative bacteria, gram-positive bacteria, fungi and drug-resistance bacteria. Moreover, the full-thickness skin defect model experiments showed that AC hydrogels could reduce inflammatory cell infiltration and accelerate wound healing significantly. The hydrogel can shed new light on designing of the multifunctional dressings for wound healing. [Display omitted] • Injectable, self-healing physically crosslinked chitosan hydrogels were designed. • Hydrogels had antibacterial activity and promoting cell proliferation activity. • Hydrogels exhibited good hemocompatibility and hemostatic properties. • Hydrogels with high degree of substitution significantly accelerated wound healing. [ABSTRACT FROM AUTHOR]

Gastric carcinoma (GC), hepatocellular carcinoma (HCC) and pancreatic carcinoma (PC) are gastrointestinal cancers (GIC) with high mortality, which seriously threaten health of the global population. The Chinese herbal medicine Astragalus membranaceus (AM) is widely used in anti-cancer treatment, including GIC. However, the potential pharmacological mechanism remains unclear. This study aimed to investigate the underlying mechanism of AM in the treatment of GIC based on network pharmacology. The database TCMSP was employed to identify the effective chemical components and potential targets of AM. GeneCards and DisGeNET databases were employed to screen associated genes of GIC. The active compounds and targets of AM in treating GIC were identified through network pharmacologic analysis. GO and KEGG enrichment analyses and survival analysis were performed to predict the anti-cancer mechanism and hub genes of AM in treating GIC. A total of 17 active compounds and 110 targets involving AM for treating GIC were identified. Quercetin, kaempferol, formononetin, isorhamnetin, 7-O-methylisomucronulatol and calycosin are main active compounds of AM for treating GIC. AKT1, CCND1, CASP3, EGF, FOS, IL6, IL10, JUN, MAPK1, MAPK8, MMP2, MMP9, MYC, PTEN, PTGS2 (COX-2), TNF and VEGFA are the hub genes for AM for treating GIC. AM mainly plays an anti-GIC role by regulating PI3K-Akt signaling pathway, MAPK pathway and TNF pathway. The potential molecular mechanism of AM in treating GIC were unveiled based on network pharmacology analysis at the first time, which may provide a new strategy for the development of more effective anti-cancer drugs. [ABSTRACT FROM AUTHOR]

• A one-dimensional design method for supercritical carbon dioxide cycles is proposed. • Detailed preliminary design method for turbomachinery and heat exchangers are given. • Demonstration design and comparative analysis of recompression cycles are performed. • Some design considerations for the recompression cycle are presented. The state-of-the-art supercritical carbon dioxide Brayton cycles are complex integrated systems featured with strong coupling effects between the cycle and components. To reveal cycle characteristics precisely and conduct cycle design efficiently, integration of the cycle design and components design are required at the very beginning. In this paper, a one-dimensional design methodology for supercritical carbon dioxide Brayton cycles was proposed, based on the integration between cycle conceptual design and components preliminary design. Details of the preliminary design methodology for turbomachinery and heat exchangers were presented. A 500kWe and 5MWe recompression cycle were designed as demonstration examples, and comparative analysis of cycle performance and components performances were performed. Meanwhile, parametric analysis of some crucial parameters was carried out and some design considerations for recompression cycle were presented. Design results suggest that the 5MWe cycle could reach a higher thermal efficiency of 38.0% compared with 37.0% for the 500kWe cycle, which fundamentally results from the larger mass flow rate. The enhanced mass flow rate would lead to higher turbomachinery efficiency in the 5MWe cycle, and the stator loss reductions contribute to the turbomachinery efficiency improvements. As for the design of recompression cycle, selecting a flow split ratio smaller than its optimum value and a reasonably high effectiveness for each recuperator is recommended. Keeping the rotation speed of the re-compressor within its optimum region is also suggested, especially for low-power cycles. Besides, the main-compressor inlet temperature is a crucial parameter, and a compromise between cycle efficiency and system maintenance should be made. [ABSTRACT FROM AUTHOR]

The transonic high-pressure turbine is a critical component in modern aviation engines which is susceptible to geometric variations throughout its entire lifecycle. However, the specific impact and underlying mechanism of geometric deviations on the performance are not yet fully understood. This article presents a framework for modeling, quantifying, and analyzing geometric variations in typical transonic high-pressure turbines. It aims to investigate the mechanism by which geometric variations impact aerodynamic performance across the entire operating range. Additionally, the study explores potential improvement methods for controlling the adverse effects caused by geometric deviations. The results indicate that within the entire operating range, the trailing edge and throat have the greatest impact on the fluctuation of total pressure loss. Deviation in the trailing edge and throat directly impacts the range of the base region and base pressure, leading to changes of shock waves and wake flow. This causes fluctuations in shock wave loss and trailing edge loss, ultimately resulting in the fluctuation of total pressure loss. Subsequently, two methods were proposed to suppress the influence of geometric deviations: the utilization of an elliptical trailing edge and a specially designed throat profile. These approaches effectively reduce the loss fluctuations caused by geometric deviations, particularly under typical transonic conditions. [ABSTRACT FROM AUTHOR]

Chronic Liver fibrosis may progress to liver cirrhosis and hepatocellular carcinoma (HCC), hence cause a substantial global burden. However, effective therapies for blocking fibrosis are still lacking. Although mesenchymal stem cells (MSCs) have been proven beneficial to liver regeneration after damage, the underlying mechanism of their therapeutic effects are not fully understood. Oxidative stress and mitochondrial functionality alteration directly contributes to the hepatocyte apoptosis and development of liver fibrosis. This study aims to elucidate the mechanism by which hUC-MSC alleviates liver fibrosis and mitochondrial dysfunction. RNA-sequencing was performed to characterize the transcriptomic changes after implantation of hUC-MSCs in mice with liver fibrosis. Next, western blot, RT-PCR, immunohistochemical and immunofluorescence staining were used to evaluate the expression of different genes in vitro and in vivo. Additionally, mitochondrial morphological and dynamic changes, ROS content, and ATP production were examined. Slc25a47, a newly identified liver-specific mitochondrial NAD+ transporter, was notably reduced in CCl 4 -treated mice and H 2 O 2 -stimulated hepatocytes. Conversely, hUC-MSCs increased the Slc25a47 expression and NAD+ level within mitochondria, thereby enhanced Sirt3 protein activity and alleviated mitochondrial dysfunction in the liver. Furthermore, Slc25a47 knockdown could partially abrogate the protective effects of hUC-MSCs on H 2 O 2 -induced mitochondrial fission and oxidative stress in hepatocytes. Our study illustrates that Slc25a47 is a key molecular for hUC-MSCs to improve liver fibrosis and regulates mitochondrial function through Sirt3 for the first time, and providing a theoretical basis for the clinical translation of hUC-MSCs transplantation in the treatment of patients with liver fibrosis/cirrhosis. • hUC-MSCs transplantation alleviate mice liver fibrosis and improve liver function. • mitochondrial NAD+ transporter Slc25a47 was decreased under stressful conditions. • hUC-MSCs reduced hepatic oxidative stress and mitochondrial damage. • hUC-MSCs improve mitochondrial dysfunction via increasing Slc25a47 expression and protein activity of Sirt3. [ABSTRACT FROM AUTHOR]

Squealer tips are widely used in high-pressure axial turbines to control tip leakage loss. A well-designed squealer tip is essential for improving the turbine aerodynamic performance. This paper aims to obtain some guidelines for the flow organization in the squealer tip gap. Firstly, to investigate the effects of tip flow organization on the turbine aerodynamic performance, four different squealer tips are constructed by analyzing the flow and loss characteristics of the conventional squealer tip. Then, the refined flow organization results are detailedly analyzed. Finally, the effects of tip flow organization on the turbine aerodynamic performance are investigated. Results show that the key to the refined flow organization in the squealer gap is to manage the vortices inside the cavity, especially the scraping vortex. The primary object in the refined flow organization is to enlarge the extent of the effective control region, enhance its intensity, and place it within the high-leakage region in the meantime. The characteristics of the effective control region are primarily determined by the characteristics of the scraping vortex, such as the streamwise range, cross-location, size and intensity. Organizing the scraping vortex carefully through a refined design for the squealer geometry can control the leakage flow and hence the leakage loss effectively, which provides an effective means for the design of the high-performance squealer tip. [ABSTRACT FROM AUTHOR]

• Polytropic efficiency serves better as a similitude parameter than isentropic efficiency in performance conversion. • A unified performance conversion method with wider applicability and higher accuracy is proposed. • The accuracy can be further improved by deep learning when the method is applied to real gas compressors. The similitude method for compressors working with different gases makes it possible to obtain the performance map of a gas compressor through the experiment of a similar air compressor, which thereby largely simplifies the test rig and saves the cost. Existing similitude methods choose isentropic efficiency as the similitude parameter, which cannot take into account all the impact factors (e.g. the real-gas effect) in the performance conversion, thus resulting in limited applications. In this paper, the similitude parameter for efficiency is theoretically deduced by analyzing the essential polytropic compression process. It is proved that polytropic efficiency serves as a more unified similitude parameter than isentropic efficiency. On this basis, a unified performance conversion method is first proposed and then validated. Results show that the unified method can be applied to all kinds of gases, including incompressible gases, ideal gases, and real gases. Relative errors in the performance conversion are less than 4% for weak real-gas-effect gases while about 6% for strong real-gas-effect gases. To further reduce the errors for strong real-gas-effect gases, two correction coefficients are introduced and deep learning technology are adopted to predict their values. It is validated that errors can be reduced to less than 2% by the deep-learning improvement. [ABSTRACT FROM AUTHOR]

• Water-soluble thymine-modified chitosan (TC) derivatives were synthesized. • TC derivatives have broad-spectrum antibacterial activities. • TC derivatives display excellent hemocompatibility, cytocompatibility and antioxidant activity. • TC sponges with high degree of substitution can significantly accelerate wound healing. Avoiding wound infections is a major challenge in wound care management, and new materials are urgently needed to address these problems. Herein, four water-soluble thymine-modified chitosan (TC) derivatives with the degree of substitution (DS) ranging from 0.23 to 0.62 were synthesized and freeze-dried to obtain porous sponge dressings. TC derivatives had broad-spectrum antibacterial activities against gram-negative bacteria, gram-positive bacteria, fungi, drug-resistance bacteria, Pseudomonas aeruginosa and Acinetobacter baumannii. Especially, the antioxidant and antibacterial properties of TC derivatives increased with increasing DS. Furthermore, TC derivatives showed excellent biocompatibility and blood compatibility. TC sponges could significantly accelerate the wound healing process than gauze and chitosan sponge. The histological analysis and immunohistochemical staining showed that the wounds treated with TC sponges displayed fewer inflammatory cells, and faster regeneration of epithelial tissue, collagen deposition and new blood vessel formation speed. Therefore, TC sponges can shed new light for wound dressing design. [ABSTRACT FROM AUTHOR]

Nonoperative treatments for Stress Urinary Incontinence (SUI) represent an ideal treatment method. Mesenchymal stem cell (MSCs) treatment is a new modality, but there is a lack of research in the field of gynecological pelvic floor and no good method to induce internal MSC homing to improve SUI. Herein, we develop an injectable and self-healing hydrogel derived from β-chitin which consists of an amino group of quaternized β-chitin (QC) and an aldehyde group of oxidized dextran (OD) between the dynamic Schiff base linkage.it can carry bFGF and SDF-1a and be injected into the vaginal forearm of mice in a non-invasive manner. It provides sling-like physical support to the anterior vaginal wall in the early stages. In the later stage, it slowly releasing factors and promoting the homing of MSCs in vivo, which can improve the local microenvironment, increase collagen deposition, repair the tissue around urethra and finally improve SUI (Scheme 1). This is the first bold attempt in the field of pelvic floor using hydrogel mechanical support combined with MSCs homing and the first application of chitin hydrogel in gynecology. We think the regenerative medicine approach based on bFGF/SDF-1/chitin hydrogel may be an effective non-surgical approach to combat clinical SUI. [ABSTRACT FROM AUTHOR]

• A novel thermodynamic cycle of precooled airbreathing engine HAPE is proposed. • A better compromise between the specific impulse and system complexity is achieved. • The charge control of HAPE has a wider range of thrust regulation. • The bypass control of HAPE is easier to implement but the regulation range is limited. The precooled airbreathing engine is a promising propulsion concept for horizontal takeoff and landing hypersonic aircraft. The helium closed cycle has been introduced in the precooled airbreathing engine such as the Synergetic Air-Breathing Rocket Engine to enhance safety and thermal efficiency of the engine, whereas increasing the system complexity inevitably. To achieve a better compromise between the specific impulse and system complexity, a novel thermodynamic cycle layout was proposed in this paper. The air was moderately precooled in the precooler at high flight Mach number, and a relatively simple two branches splitting-cooling-recompression scheme was adopted in the helium closed cycle, as well as a bypass engine path with small bypass ratio was introduced to burn the excess hydrogen. Firstly, the parametric analysis of key design variables and performance optimization were carried out at the Mach 5.0 design point, and the specific impulse could reach a value of up to 3282 s. The engine was controlled by adjusting the air & fuel path and the helium closed cycle simultaneously. As for the air & fuel path, the amount of liquid hydrogen used for cooling and combustion could be equilibrium by adjusting the equivalence ratio in the bypass combustor and the area of bypass nozzle throat concurrently. In the helium closed cycle, the charge control and bypass control methods were adopted separately. The engine thrust could be effectively regulated over a wider range as well as all the main components work stably under the charge control. The results show that the bypass control is easier to implement but the regulation range of thrust is limited. The overall engine performance calculated along a typical flight trajectory shows that this simplified precooled airbreathing engine cycle has comparatively high specific impulse from take-off to Mach 5.0. As the helium closed cycle layout is relatively simple, it is maybe easier to achieve engineering realization. [ABSTRACT FROM AUTHOR]