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The purpose of this study was to investigate the effect of different times return to activity on tendon healing after Double Kessler method suture in rats with Achilles tendon rupture. The left Achilles tendon of 80 10-week-old rats was repaired. The rats were randomly divided into 4 groups: non-fixed group, fixed one week group, fixed two weeks group and fixed three weeks group. In the fourth week, all rats were trained on a treadmill for one hour a day at a speed of 10 m/min. Complications were recorded during the study period and passive ankle motion was measured after the rats were euthanized. The healing and adhesion of tendons were evaluated by anatomy, biomechanics, histology and immunohistochemistry. The earlier return to activity after surgery, the higher the quality of tendon healing and the less adhesion will occur. There was no difference in complication rate among the four groups (P< 0.05). There was one case of tendon re-rupture in the non-fixed group and one case in the fixed one week group. The passive range of motion, biomechanical properties, histological evaluation and immunohistochemical results of the ankle in non-fixed group were better than those in the other three groups, while those in fixed three weeks group were worse than those in the other three groups (P< 0.05). The passive ankle range of motion, count of fibroblasts, biomechanical results, and immunohistochemical results showed no statistic significant difference between the fixed one week group and fixed two weeks group (P> 0.05). Early return to activity with strong sutures is advantageous for tendon injuries. With the advanced of return to activity time, the healing strength of tendon increased and the degree of adhesion decreased four weeks after surgery. [ABSTRACT FROM AUTHOR]

Media visual sculpture is a landscape element with high carbon emissions. To reduce carbon emission in the process of creating and displaying visual art and structures (visual communication), geo-polymer concrete (GePC) is considered by designers. It has emerged as an environmentally friendly substitute for traditional concrete, boasting reduced carbon emissions and improved longevity. This research delves into the prediction of the compressive strength of GePC (CSGePC) employing various soft computing techniques, namely SVR, ANNs, ANFISs, and hybrid methodologies combining Genetic Algorithm (GA) or Firefly Algorithm (FFA) with ANFISs. The investigation utilizes empirical datasets encompassing variations in concrete constituents and compressive strength. Evaluative metrics including RMSE, MAE, R2, VAF, NS, WI, and SI are employed to assess predictive accuracy. The results illustrate the remarkable precision of all soft computing approaches in predicting CSGePC, with hybrid models demonstrating superior performance. Particularly, the FFA-ANFISs model achieves a MAE of 0.8114, NS of 0.9858, RMSE of 1.0322, VAF of 98.7778%, WI of 0.9236, R2 of 0.994, and SI of 0.0358. Additionally, the GA-ANFISs model records a MAE of 1.4143, NS of 0.9671, RMSE of 1.5693, VAF of 96.8278%, WI of 0.8207, R2 of 0.987, and SI of 0.0532. These findings underscore the effectiveness of soft computing techniques in predicting CSGePC, with hybrid models showing particularly promising results. The practical application of the model is demonstrated through its reliable prediction of CSGePC, which is crucial for optimizing material properties in sustainable construction. Additionally, the model's performance was compared with the existing literature, showing significant improvements in predictive accuracy and robustness. These findings contribute to the development of more efficient and environmentally friendly construction materials, offering valuable insights for real-world engineering applications. [ABSTRACT FROM AUTHOR]

The growing demand for energy storage has drawn considerable attention to devices such as supercapacitors, which currently lack high energy density but depict high power density and long cycle life. In this work, we have synthesized La0.3Sr0.7Ti0.5Fe0.5O3 (LSTF) nanoparticles and Ti3C2‐MXene‐modified LSTF nanoparticle hybrid to study the effect of MXene on electrochemical properties of the nanoparticles. The X‐ray diffraction (XRD) and Raman spectroscopy analysis showed that the hybrid structure retained all the major peaks of the nanoparticles and the MXene, which showed its successful synthesis. The morphological analysis was done utilizing scanning electron microscopy (SEM), which verified that the nanoparticles had been adsorbed and/or agglomerated onto the MXene sheets. The electrochemical analysis showed that with the addition of MXene into the nanoparticles, the specific capacitance tested via cyclic voltammetry increased from 225.6 Fg‒1 to 419.5 Fg‒1 at the scan rate of 2 mVs-1, which makes the hybrid a suitable electrode material for supercapacitors. The value of specific capacitance for the hybrid tested via galvanostatic charge‐discharge showed an increased value of 23 Fg‒1 at the current density of 1 Ag-1. The Fourier transform infrared (FTIR) spectroscopy showed that the hybrid contains –O functional groups coming from MXene, which causes an increase in electrochemical activity at the electrode surface, resulting in enhanced capacitance. [ABSTRACT FROM AUTHOR]

In order to investigate the impact of design parameters (depth, width, and location) of the single-circumferential groove (SCG) on tip leakage flow (TLF) reduction in a transonic turbine stage, a systematic investigation was conducted by high-precision numerical simulation method. The numerical results show that the introduction of SCG could improve the stage efficiency (η) of turbine significantly. The optimal design parameters of depth coefficient (ζ), width (W), and location (L) were ζ = 3, W = W3, and L = 20%Cax (where Cax denotes the axial chord of the blade), which could reduce tip clearance leakage rate (m*) by 28.9% and improve the η by 0.56%. The implementation of flow field display methods reveals that the introduction of SCG influences the formation and development of the vortex system at the rotor tip region. The circumferential groove vortex (CGV), induced by SCG, divided the tip leakage vortex (TLV) into two segments TLV_1 and TLV_2 due to its blocking effect. TLV_1 interacted with the passage vortex (PV) and depress the strength of PV. Meantime, TLV_2 would regenerate from the trailing edge of SCG, due to its limited development range and insufficient growth, the strength and scale of TLV_2 were weakened. Given that the TLF passing through SCG flows in an opposite direction to the original TLF, the SCG at appropriate location could lead to a fact that the net flow rate of the leakage flow reached the minimum value, thereby considerably reducing the m* and flow loss caused by TLF. [ABSTRACT FROM AUTHOR]

In order to promote sustainable energy development and reduce the impact of fossil fuels on the environment, it is crucial to strengthen the development and utilization of clean and renewable geothermal energy. Liquid nitrogen fracturing, as an emerging waterless fracturing technology, has outstanding advantages in rock fracturing effect and thermal exchange ability with hot dry rock and is more environmentally friendly. In order to evaluate the influence of liquid nitrogen on the mechanical properties, acoustic emission characteristics, and cross-sectional crack propagation characteristics of granite at different initial temperatures, this paper carried out three-point bending tests and acoustic emission detection on granite treated by high-temperature heating and liquid nitrogen cooling. Finally, based on the cross-sectional scanning test, the expansion characteristics of microcracks in granite were analyzed. The results show that the higher the initial temperature of granite, the stronger the cold impact of liquid nitrogen on granite, and the faster the rock's mechanical performance declines. The acoustic emission ringing count is closely related to the development of microcracks in granite, and as the initial temperature of granite increases, the more ringing counts there are, indicating that the huge temperature difference induces more microcracks inside the rock. In addition, the cold impact of liquid nitrogen can effectively promote the fracturing of granite. After liquid nitrogen treatment, the fractal dimension of the granite cross-section increases, the shape of the cross-section becomes rough, and many micropores appear. This study can provide a scientific basis for the engineering application of liquid nitrogen fracturing technology. [ABSTRACT FROM AUTHOR]

Dry hot rock geothermal resources by virtue of its wide distribution, large reserves, clean and low-carbon, stable, high utilization rate, and other characteristics have been widely used. The enhanced geothermal system (EGS) is the most efficient approach for harnessing and exploiting geothermal energy from hot, arid rock formations. To investigate the impact of varying parameters on heat recovery in EGS operations, we employed the COMSOL numerical simulation software to construct a seepage heat transfer model for fractured rock masses. Essential parameters and boundary conditions were established, followed by conducting numerical simulations. Through the numerical simulation results, the temporal and spatial changes of coupling effects among seepage field, stress field, and temperature field in fractured rock mass were analyzed. We investigated the impact of water injection temperature, injection-production pressure difference, injection flow rate, and initial reservoir temperature on the heat transfer process. The findings indicate that raising the water injection temperature and injection-production pressure difference can enhance the reservoir's heat recovery capability. However, it may also accelerate thermal breakthrough and reduce the system's operational lifespan. The higher injection flow rate can improve the heat recovery efficiency. However, too large injection flow can cause problems in other aspects of the reservoir; increasing reservoir temperature leads to higher production temperatures, which can potentially result in dynamic catastrophes. Therefore, while ensuring the heat recovery efficiency of the system, the operation life of the system can be extended by adjusting the water injection temperature in stages, setting a reasonable injection and production pressure difference, and selecting an appropriate injection flow rate, so as to achieve the purpose of EGS optimization. [ABSTRACT FROM AUTHOR]

Avian influenza A virus H5N1 is a highly pathogenic and persistently a major threat to global health. Vaccines and antibodies targeting hemagglutinin (HA) protein are the primary management strategies for the epidemic virus. Although camelids possess unique immunological features, the immune response induced by specific antigens has not yet been thoroughly investigated. Herein, we immunized an alpaca with the HA antigen of the H5N1 virus and performed single-cell transcriptome profiling for analysis of longitudinal peripheral blood mononuclear cell (PBMCs) behavior using single-cell sequencing technology (scRNA-seq). We revealed multiple cellular immunities during the immunization. The monocytes continued to expand after immunization, while the plasma cells reached their peak three days after the second antigen stimulation. Both monocytes and B cells were stimulated by the HA antigen and produced cell-type-specific cytokines to participated in the immune response. To our knowledge, this is the first study to examine the HA-specific immunological dynamics of alpaca PBMCs at the single-cell level, which is beneficial for understanding the anti-viral immune system and facilitating the development of more potent vaccines and antibodies in camelid animals. [ABSTRACT FROM AUTHOR]