Search Results (239)

To enhance the operational stability of distribution networks during peak periods, this paper proposes a multi-timescale operational method considering load forecasting impacts. Firstly, the Crested Porcupine Optimizer (CPO) is employed to optimize the hyperparameters of long short-term memory (LSTM) networks for an accurate prediction of the next-day load curves. Building on this foundation, a multi-timescale optimization strategy is developed: During the day-ahead operation phase, a conservation voltage reduction (CVR)-based regulation plan is formulated to coordinate the control of on-load tap changers (OLTCs) and distributed resources, alleviating peak-shaving pressure on the upstream grid. In the intraday optimization phase, real-time adjustments of OLTC tap positions are implemented to address potential voltage violations, accompanied by an electrical distance-based control strategy for flexible adjustable resources, enabling rapid voltage recovery and enhancing system stability and robustness. Finally, a modified IEEE-33 node system is adopted to verify the effectiveness of the proposed multi-timescale operational method. The method demonstrates a load forecasting accuracy of 93.22%, achieves a reduction of 1.906% in load power demand, and enables timely voltage regulation during intraday limit violations, effectively maintaining grid operational stability. Full article

With the increasing capacity of wind turbines, key components including the rotor diameter, tower height, and tower radius expand correspondingly. This heightened inertia extends the response time of pitch actuators during rapid wind speed variations occurring above the rated wind speed. Consequently, wind turbines encounter significant output power oscillations and complex structural loading challenges. To address these issues, this paper proposes a novel pitch control strategy combining an effective wind speed estimation with the inverse system method. The developed control system aims to stabilize the power output and rotational speed despite wind speed fluctuations. Central to this approach is the estimation of the aerodynamic rotor torque using an extended Kalman filter (EKF) applied to the drive train model. The estimated torque is then utilized to compute the effective wind speed at the rotor plane via a differential method. Leveraging this wind speed estimate, the inverse system technique transforms the nonlinear wind turbine dynamics into a linearized, decoupled pseudo-linear system. This linearization facilitates the design of a more agile pitch controller. Simulation outcomes demonstrate that the proposed strategy markedly enhances the pitch response speed, diminishes output power oscillations, and alleviates structural loads, notably at the tower base. These improvements bolster operational safety and stability under the above-rated wind speed conditions. Full article

High pH, ${\mathrm{Na}}^{+}$, and $({\mathrm{CO}}_3^{2-}+{\mathrm{HCO}}_3^{-}$) are the primary characteristics of soda saline–alkali soil. Current strategies for ameliorating soda saline–alkali soil often involve the combined use of cow manure and maize straw, the addition of biochar (BC), and the inoculation of Bacillus subtilis (BS). In this study, B. subtilis-loaded biochar (BSC) was prepared using an adsorption technique. An incubation experiment was conducted. The treatments were as follows: soda saline–alkali soil amended with maize straw and cow manure (T₁), which was used as a control; T₁ supplemented with earthworms (T₂); and T₂ supplemented with BS (T₃), BC (T₄), or BSC (T₅). After a 60-day incubation, T₅ showed the most significant reduction in pH, ESP, and (${\mathrm{H}\mathrm{C}\mathrm{O}}_3^{-}$ + ${\mathrm{C}\mathrm{O}}_3^{2-}$) concentrations, with reductions of 0.24 units, 3.26%, and 120 mg kg⁻¹, respectively, compared to the T₁ treatment. The content of soil humic acid, available potassium, and available nitrogen and the activities of β-glucosidase and urease were highest in T₅, increasing by 33.5%, 70.1%, 26.1%, 19.0%, and 17.9%, respectively. Microbial sequencing analysis revealed that the Bacillus abundance in T₃ was highest during the first 45 days (2.51–3.65%), while the Bacillus abundance in T₅ peaked at 3.22% after the 60-day incubation. The soil that was cultivated for 60 days in the experiments was then used for planting alfalfa. T₅ showed the highest alfalfa aboveground biomass and peroxidase, increasing by 30.1% and 73.1%, respectively, compared with T₁. This study demonstrated that loading onto biochar is beneficial for the survival of B. subtilis in soda saline–alkali soil. When traditional organic materials are used, the combination of earthworms and B. subtilis-loaded biochar significantly alleviates the constraints of soda saline–alkali soil. Full article

To resolve the critical issues of severe deformation, structural failure, and maintenance difficulties in the advanced reuse zone of gob-side-entry retaining roadways under pillarless mining conditions in ultra-long fully mechanized top-coal caving isolated mining faces, this study proposes a surrounding rock control technology incorporating pressure relief through roof cutting. Taking the 3203 ultra-long isolated mining face at Nanyang Coal Industry as the engineering case, an integrated methodology combining laboratory experiments, theoretical analysis, numerical simulations, and industrial-scale field trials was implemented. The deformation and failure mechanism of flexible formwork walls in gob-side-entry retaining and the fundamental principles of pressure relief via roof cutting were systematically examined. The vertical stress variations in the advanced reuse zone of the retained roadway before and after roof cutting were investigated, with specific focus on the strata pressure behavior of roadways and face-end hydraulic supports on both the wide coal-pillar side and the pillarless side following roof cutting. The key findings are as follows: ① Blast-induced roof cutting reduces the cantilever beam length adjacent to the flexible formwork wall, thereby decreasing the load per unit area on the flexible concrete wall. This reduction consequently alleviates lateral abutment stress and loading in the floor heave-affected zone, achieving effective control of roadway surrounding rock stability. ② Compared with non-roof cutting, the plastic zone damage area of surrounding rock in the gob-side entry retained by flexible formwork concrete wall is significantly reduced after roof cutting, and the vertical stress on the flexible formwork wall is also significantly decreased. ③ Distinct differences exist in the distribution patterns and magnitudes of working resistance for face-end hydraulic supports between the wide coal-pillar side and the pillarless gob-side-entry retaining side after roof cutting. As the interval resistance increases, the average working resistance of hydraulic supports on the wide pillar side demonstrates uniform distribution, whereas the pillarless side exhibits a declining frequency trend in average working resistance, with an average reduction of 30% compared to non-cutting conditions. ④ After roof cutting, the surrounding rock deformation control effectiveness of the track gateway on the gob-side-entry retaining side is comparable to that of the haulage gateway on the 50 m wide coal-pillar side, ensuring safe mining of the working face. Full article

Oxidative stress and chronic inflammation play pivotal roles in causing impaired tissue regeneration and delaying wound healing processes. Epigallocatechin gallate (EGCG) demonstrates robust anti-inflammatory and antioxidant characteristics, thereby emerging as a highly promising therapeutic substance for tissue repair applications. In order to counteract the pathological characteristics of the wound microenvironment, including increased levels of reactive oxygen species (ROS), low pH (weak acidic conditions), and elevated glucose concentrations, a hydrogel with pH/ROS/glucose-responsive properties was fabricated. This hydrogel was modified with phenylboronic acid (PBA) groups, which not only enhance its mechanical strength but also endow it with multi-stimuli responsiveness via dynamic boronate ester bonds. The impacts of grafting of PBA and loading of EGCG on the rheological and mechanical properties, as well as the network structure of the hydrogels, were systematically investigated. Moreover, in vitro experiments showed that the hydrogel could achieve excellent sustained and controlled release of both small-molecule and macromolecular drugs. Additionally, cell viability tests verified the hydrogel’s outstanding biocompatibility, and antioxidant experiments demonstrated its efficient ability to scavenge intracellular ROS. In conclusion, this injectable and biodegradable hydrogel possesses multi-stimuli responsiveness, controllable drug release behavior, and antioxidant capacity, presenting a promising approach to alleviate oxidative damage and promote tissue repair. This study offers valuable perspectives for the design of advanced hydrogel materials aimed at treating wound healing. Full article

Hydropower’s ability to start up and shut down quickly, combined with its flexible regulation characteristics, effectively alleviates frequency fluctuations caused by new energy sources, ensuring the safe and stable operation of the power system. However, during peak-frequency regulation tasks, the transition processes associated with the startup, shutdown, and load changes introduce frequent shocks to subsystems such as the hydro-turbine, governor, and diversion systems. These shocks pose significant challenges to the safe and stable operation of hydropower plants. Therefore, this study constructs a coupled hydraulic–mechanical–electrical model that incorporates the diversion system, hydro-turbine, governor, generator, and load, based on operational data from a real-world hydropower plant in China. The load increase transition process is selected for parameter sensitivity analysis to evaluate the influence of various structural, operational, and control parameters on unit stability and to identify key parameters affecting stability. The results indicate that the initial load exhibits the highest sensitivity to inversion power peak and rotational speed overshoot, with sensitivity values of 0.14 and 0.0038, respectively. The characteristic water head shows the greatest sensitivity to the inversion power peak time and rotational speed peak time, with values of 0.31 and 0.43, respectively. Additionally, the integration gain significantly influences the rotational speed rise time, with a sensitivity value of 0.30. These findings provide a theoretical basis for optimizing the parameter selection in hydropower plants. Full article

Industrial workers often engage in repetitive lifting tasks. This type of continual loading on their arms throughout the workday can lead to muscle or tendon injuries. A non-intrusive system designed to assist a worker’s arms would help alleviate strain on their muscles, thereby preventing injury and minimizing productivity losses. The goal of this project is to develop a wearable soft robotic arm enhancement device that supports a worker’s muscles by sharing the load during lifting tasks, thereby increasing their lifting capacity, reducing fatigue, and improving their endurance to help prevent injury. The device should be easy to use and wear, functioning in relative harmony with the user’s own muscles. It should not restrict the user’s range of motion or flexibility. The human arm consists of numerous muscles that work together to enable its movement. However, as a proof of concept, this project focuses on developing a prototype to enhance the biceps brachii muscle, the primary muscle involved in pulling movements during lifting. Key components of the prototype include a soft robotic muscle or actuator analogous to the biceps, a control system for the pneumatic muscle actuator, and a method for securing the soft muscle to the user’s arm. The McKibben-inspired pneumatic muscle was chosen as the soft actuator for the prototype. A hybrid control algorithm, incorporating PID and model-based control methods, was developed. Electromyography (EMG) and pressure sensors were utilized as inputs for the control algorithms. This paper discusses the design strategies for the device and the preliminary results of the feasibility testing. Based on the results, a wearable EMG-controlled soft robotic arm augmentation could effectively enhance the endurance of industrial workers engaged in repetitive lifting tasks. Full article

The increasing integration of renewable energy sources has posed significant challenges to grid frequency stability. To maximize the advantages of energy storage in primary frequency regulation, this paper proposes a comprehensive control strategy for a hybrid energy storage system (HESS) based on supercapacitor battery. Firstly, considering the characteristics of the HESS and different control strategies, the battery responds to virtual droop control to reduce frequency deviation, while the supercapacitor responds to inertia control to suppress frequency drops and facilitate frequency recovery. Simultaneously, a reasonable dynamic dead zone is configured to prevent frequent actions of the battery and thermal unit while allowing flexible adjustments according to the load condition. Thirdly, an algebraic S-curve-based adaptive droop coefficient incorporating SOC is proposed, while the inertia coefficient additionally considers load type, enhancing adaptability. Furthermore, to better maintain the battery’s SOC, an improved adaptive recovery strategy within the battery dead zone is proposed, considering both SOC recovery requirements and system frequency deviation constraints. Finally, a simulation validation was conducted in MATLAB/Simulink. Compared to the conventional strategy, the proposed control strategy reduces the frequency drop rate by 17.43% under step disturbance. Under compound disturbances, the RMS of frequency deviation decreases by 13.34%, and the RMS of battery SOC decreases by 68.61%. The economic benefit of this strategy is 3.212 times that of the single energy storage scheme. The results indicate that the proposed strategy effectively alleviates sudden frequency disturbances, suppresses frequency fluctuations, and reduces battery output while maintaining the SOC of both the supercapacitor and the battery, thereby extending the battery lifespan and improving economic performance. Full article

Background: Choroid plexus is a complex structure in the human brain that is responsible for the secretion of extracellular vesicles (EVs) in cerebrospinal fluid. Few studies to date have generated choroid plexus (ChP) organoids differentiated from human induced pluripotent stem cells (hiPSCs) and analyzed their secreted EVs. The scalable Vertical-Wheel bioreactors (VWBRs) provide low shear stress and a controlled environment. Methods: This study utilized VWBRs for the differentiation of hiPSCs into ChP organoids and generation of the secreted EVs compared to a static culture. Additionally, this study loaded curcumin into ChP organoid-derived EVs, performed EV lyophilization, and determined the ability of the re-hydrated EVs to alleviate neuro-inflammation. Results: The results demonstrated that the VWBR culture exhibited more aerobic metabolism and active glucose and glutamine consumption than the static control. Consequently, the ChP markers and Endosomal Sorting Complexes Required for Transport-dependent and -independent EV biogenesis genes were significantly upregulated (2–3-fold) in the VWBR, producing four-fold-higher EVs per mL media than the static control. The EVs retained similar size and zeta potential after lyophilization and re-hydration. The cells exposed to amyloid beta 42 oligomers and treated with the curcumin-loaded re-hydrated EVs showed high viability and the reduced inflammatory response determined by TNF-α and IL-6 expression. Conclusions: This study demonstrates a scalable bioreactor system to promote ChP organoid differentiation and generation of EV-based cell-free therapeutics to treat neural inflammation in various neurological disorders. Full article

Postoperative peritoneal adhesion and high recurrence rates are critical challenges in the clinical treatment of colorectal cancer. In this study, based on amyloid-like protein self-assembly technology, a novel Janus protein film was developed. The protein film encapsulates glucose oxidase (GOx) and catalase (CAT), which is named PTL@GC. Through a one-step method involving cysteine-reduced lysozyme-induced amyloid-like self-assembly, the film was co-loaded with GOx and CAT to achieve synergistic anti-adhesion and anti-tumor recurrence effects. The Janus film features a hydrophobic side that stably adheres to the intestinal surface without exogenous chemical modification and a hydrophilic side that prevents adhesion. The loaded GOx selectively induces disulfidptosis in SLC7A11-overexpressing tumor cells, while CAT degrades H₂O₂ to alleviate hypoxia and inhibit oxidative stress, significantly reducing adhesion-related fibrosis. The experimental results demonstrate that PTL@GC exhibited excellent mechanical properties, high enzyme activity retention (>90%), and controllable degradability (complete metabolism within 50 days). In animal models, PTL@GC reduced postoperative adhesion area by 22.77%, decreased local tumor burden to 28.42% of the control group, and achieved an inhibition rate of 58.49%, without inducing systemic toxicity. This study presents a biologically safe and functionally synergistic approach to addressing dual complications following colorectal cancer surgery, offering potential insights for future research on multifunctional Janus materials. Full article

In the context of rapid advancement of smart cities, a distribution network (DN) serving as the backbone of urban operations is a way to confront multifaceted challenges that demand innovative solutions. Central among these, it is imperative to optimize resource allocation and enhance the efficient utilization of diverse energy sources, with particular emphasis on seamless integration of renewable energy systems into existing infrastructure. At the same time, considering that the traditional power system’s “rigid”, instantaneous, dynamic, and balanced law of electricity, “source-load”, is difficult to adapt to the grid-connection of a high proportion of distributed generations (DGs), the collaborative interaction of multiple flexible controllable resources, like flexible loads, are able to supplement the power system with sufficient “flexibility” to effectively alleviate the uncertainty caused by intermittent fluctuations in new energy. Therefore, an active distribution network (ADN) intraday, reactive, power optimization-scheduling model is designed. The dynamic reactive power collaborative interaction model, considering the integration of DG, energy storage (ES), flexible loads, as well as reactive power compensators into the IEEE 33-node system, is constructed with the goals of reducing intraday network losses, keeping voltage deviations to a minimum throughout the day, and optimizing static voltage stability in an active distribution network. Simulation outcomes for an enhanced IEEE 33-node system show that coordinated operation of source–network–load–storage effectively reduces intraday active power loss, improves voltage regulation capability, and achieves secure and reliable operation under ADN. Therefore, it will contribute to the construction of future smart city power systems to a certain extent. Full article

This study aims to explore the therapeutic potential of Angelicae Pubescentis Radix (APR), a traditional Chinese medicine that is widely known for its anti-inflammatory, anti-oxidative, and anti-microbial properties, using a mouse model. In this study, 30 mice were selected and divided into three groups: control group (CD), infection group (ED), and treatment group (TD). Mice in the TD were gavaged with APR oil (0.15 mL/kg/day) for 20 days, while mice in the CD and ED received an equal volume of normal saline. On the 21st day, mice in the ED and TD were infected with multi-drug-resistant E. coli (1 × 10⁷ CFU/mL) derived from diarrheal yak. Twenty-four hours later, all mice were euthanized, and blood, organs, and intestinal samples were collected for analysis. The results of intestinal sections and intestinal bacterial load revealed that APR treatment significantly reduced (p < 0.05) both bacterial load and intestinal injury. Serum analysis indicated that APR treatment also alleviated the inflammation and oxidative stress induced by E. coli infection. Intestinal microbiota sequencing further showed that APR treatment increased the abundance of intestinal probiotics such as Ligilactobacillus, Paludicola, and Blautia_A_1417806 while also enhancing the enrichment of functional pathways associated with antioxidant defense. In conclusion, APR treatment effectively alleviates diseases caused by E. coli infection, promotes the growth of beneficial intestinal bacteria, and improves the antioxidant capacity in animals. Additionally, these findings confirm APR’s role in addressing immediate effects rather than chronic adaptations. Future studies should investigate the prolonged effects of APR treatment beyond the acute phase. Full article

Cannabidiol (CBD) has gained popularity in veterinary medicine for its potential to alleviate stress, pain, and inflammation in dogs. However, its oral administration is limited by hydrophobicity, variable absorption, and extensive first-pass metabolism, which requires optimized delivery methods to enhance efficacy. This study investigated the effects of daily oral supplementation of CBD oil and CBD gel (each at 4 mg/kg), compared to a placebo, over 14 days in shelter dogs subjected to solitary confinement-induced stress. Both CBD formulations appeared safe under the study conditions, with no adverse effects on hematological and biochemical parameters. Post-stress cortisol levels were significantly lower in CBD-treated groups compared to controls, with CBD-infused gel showing a pattern toward greater attenuation. Multivariate analysis revealed distinct blood profile shifts in CBD-treated dogs, with PCA loadings indicating associations between CBD supplementation and lymphocyte percentages and IgG levels. These findings support gel-based CBD as a promising strategy for stress modulation in dogs. Further studies should explore its pharmacokinetics and long-term immune effects to optimize veterinary applications. Full article

Ground temperature conditions are key factors affecting the stability of cast-in-place pile foundations for transmission towers in permafrost regions. With global climate warming, the ground temperature environment in permafrost regions has undergone significant changes, leading to an increasing risk of disasters for these pile foundations. However, research on the prevention and control of pile foundation diseases caused by permafrost degradation is relatively limited, and engineering practices are insufficient. To address this, this study proposes embedding a two-phase closed thermosyphon (TPCT) inside a concrete pile foundation to create a composite structural system with both load-bearing and cooling functions. A mathematical model is developed to focus on the cooling performance and temperature control efficiency of the composite structure. The results indicate that: (1) The TPCT can alleviate, to some extent, the downward shift of the permafrost table around the transmission tower foundation due to climate warming. The cooling effect of the TPCT slows the rate of permafrost degradation, but its control effect on the permafrost table is limited. (2) The performance of the cast-in-place piles with an embedded TPCT is closely related to temperature, with an effective operational period from early October to late March each year. (3) This device effectively mitigates the impact of permafrost degradation due to climate change, significantly lowering the risk of foundation-related issues in transmission towers. The findings of this study are crucial for maintaining ground temperature stability in cast-in-place pile foundations for transmission projects in high-latitude permafrost areas, as well as enhancing the theoretical framework for pile foundation design. Full article

Psoriasis is a chronic and recurrent inflammatory disease driven not only by intrinsic factors such as immune system dysregulation but also by external factors, including bacterial infections. In contrast to the control of a single pathogenic pathway, combination therapies addressing both the immune and infectious components of psoriasis pathogenesis may offer a more effective strategy for controlling its progression. In this study, we developed a sprayable hydrogel incorporating tea polyphenol-loaded lauric acid liposomes (TP@LA-Lipo gel) to investigate its anti-inflammatory and antibacterial role in psoriasis. Our results demonstrated that TP@LA-Lipo modulated macrophage activity, reduced the expression of iNOS and TNF-α, and remodeled the immune microenvironment. Meanwhile, TP@LA-Lipo effectively eliminated Staphylococcus aureus and Escherichia coli through membrane disruption, mitigating the provoked inflammatory response. More importantly, TP@LA-Lipo gel, when sprayed onto the psoriasis lesions, provided sustained drug release over three days, enabling deeper penetration through the thickened stratum corneum to reach the inflamed layers beneath. Furthermore, in an imiquimod-induced psoriasis mouse model, TP@LA-Lipo gel effectively restored the damaged skin, alleviated histopathological changes, and reduced the systemic immune response. In summary, these findings indicate that TP@LA-Lipo gel offers a comprehensive strategy for effective disease management and improving the quality of life for psoriasis patients. Full article