Science Progress最新文献

Bronchial schwannoma is a rare benign tumor traditionally managed through surgical resection. This case report describes a 69-year-old Chinese woman with an asymptomatic bronchial schwannoma incidentally discovered during routine health check-up. Computed tomography (CT) and bronchoscopy revealed a broad-based mass (27 mm × 16 mm) at the right lower lobe bronchus, causing complete obstruction of the dorsal segment and severe stenosis (>80%) of the basal segment. Histopathological and immunohistochemical analyses confirmed the diagnosis of schwannoma. The patient underwent a single-session multimodal bronchoscopic treatment combining cryotherapy, high-frequency electrocoagulation, and laser therapy, with minimal bleeding (<5 ml). Post-intervention evaluation showed a fully patent right lower lobe bronchus, and at 8-month follow-up, CT confirmed complete resolution without tumor recurrence. This case demonstrates that carefully planned bronchoscopic intervention can effectively manage selected cases of bronchial schwannoma while preserving lung function and minimizing procedural risks.

Objective: The pathological mechanism of osteoporosis (OP) involves increased bone resorption mediated by osteoclasts and decreased bone formation mediated by osteoblasts, leading to an imbalance in bone homeostasis. Identifying key molecules in osteoclast-mediated OP progression is crucial for the prevention and treatment of OP.

Methods: Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were performed on the OP patient datasets from the GEO database. The results were intersected with the differential expression results from the osteoclast differentiation dataset to identify key genes. These key genes were then subjected to disease relevance analysis, and consensus clustering was performed on OP patient samples based on their expression profiles. The subgroups were analyzed for differences, followed by GO, KEGG, GSEA, and GSVA analyses, and immune infiltration. Finally, osteoclast differentiation model was constructed. After validating the success of the model using TRAP and F-actin staining, the differential expression of key genes was validated in vitro via Western blot.

Results: CTRL, ARHGEF5, PPAP2C, VSIG2, and PBLD were identified as key genes. These genes exhibited strong disease relevance (AUC > 0.9). Functional enrichment results also indicated their close association with OP and osteoclast differentiation. In vitro differential expression validation showed that during osteoclast differentiation, CTRL was downregulated, while ARHGEF5, PPAP2C, VSIG2, and PBLD were upregulated, with all differences being statistically significant (P < 0.05).

Discussion: Currently, there are no studies on the effects of these five genes on osteoclast differentiation. Therefore, it is meaningful to design in vivo and in vitro perturbation experiments to observe the impact of each gene on osteoclast differentiation and OP progression.

Conclusion: CTRL, ARHGEF5, PPAP2C, VSIG2, and PBLD show high potential as molecular targets for basic and clinical research in osteoclast-mediated OP.

Asphalt pavements are consistently subjected to environmental and loading conditions that affect their durability, such as oxidative aging. Modification of the pavements assists in reducing the aging-induced stiffness. One of these solutions is crumb rubber (CR)-modified warm mix asphalt (WMA) binders. This study aims to assess the long-term performance and effects of aging on CR-modified WMA binders through a series of physical, rheological, and chemical tests. 2% and 4% of Sasobit, a wax-based additive, and 1.5% and 3% of Zycotherm, a nano-based chemical additive, with 10%, 15%, and 20% CR, were utilized. The binders were aged using a rolling thin film oven (RTFO) and pressurized aging vessel. The unaged and long-term aged asphalt binders were tested. Rheological properties, using master curves and zero shear viscosity, physical properties measured through elastic recovery, along with chemical analysis using Fourier transform infrared (FTIR) spectroscopy, were carried out on the binders before and after aging. Based on the physical and rheological aging indices, Sasobit-modified asphalt binders exhibited superior resistance to aging and rutting compared to Zycotherm-modified binders. Specifically, the Sasobit 4% and 20% crumb rubber blend showed the highest resistance to physical aging, while Zycotherm-modified binders demonstrated improved chemical aging resistance. Adding crumb rubber significantly enhanced the stiffness and elasticity of the asphalt binders, further reducing the effects of aging. FTIR analysis confirmed that Sasobit and crumb rubber reduced oxidation and volatile component loss during aging.

This study aims to investigate the impact of isolation piles on soil vibrations in the environment surrounding suburban railways. Initially, a comprehensive numerical model of the train was established to simulate the wheel-rail interaction forces, which were then applied to a three-dimensional coupled track-soil model. The accuracy of the model was validated through comparison with measured data. The focus of the research is to analyze the vibration isolation effects of single-row, double-row, and triple-row piles, with particular attention to the influence of pile spacing in double-row piles on isolation effectiveness. The study found that the effectiveness of isolation piles in reducing soil vibration acceleration within a depth range of 0 m to 2 m decreases as the pile spacing increases. When the pile spacing reaches 2 times the pile radius, single-row piles exhibit the best vibration isolation effect. For reducing peak soil acceleration within a depth range of 4 m to 8 m, single-row piles are most effective when the pile spacing exceeds 1 times the pile radius. To attenuate peak soil acceleration at depths greater than 6 m, the pile spacing for single-row and double-row piles should be set at 0.5 times the pile radius, while triple-row piles should have a spacing of 1 times the pile radius. In terms of reducing peak soil velocity, single-row piles demonstrate better vibration isolation effects. To reduce peak velocity in soil at depths greater than 2 m, the pile spacing for single-row and double-row piles should be set at 0.5 times the pile radius, while triple-row piles should be spaced at 1 times the pile radius. For reducing peak soil displacement, single-row piles should be used, with optimal results achieved at a spacing of 1 times the pile radius.

To meet various industrial requirements such as ease of motion, scalability, and cost efficiency, it is necessary to innovate the design of robotic platforms. In this research, a novel approach, from mechanical design to control implementation, is introduced for launching a robotic platform using a parallelogram mechanism. First, a reverse engineering process is applied, progressing from kinematics to dynamics. Then, several mechanical computations are conducted to ensure the structural stability of the robot framework. Subsequently, the dynamic performance of the system is analyzed, focusing on the driving torque and moments in each link. Additionally, the electrical design and transfer function of each joint are identified to ensure practical execution. To validate the effectiveness and feasibility of the design, both numerical simulations and experimental tests are performed. Theoretical results show the dynamic response of the proposed method, particularly in terms of the driving moments of the robotic joints. In real-world tests, various trajectories, such as different rectangular paths, are demonstrated to showcase the robot's capabilities. From these results, it is clear that the proposed approach is both feasible and applicable in practical scenarios.

Objectives: In this study, the impacts of various processing parameters on the quality and consumer satisfaction of dragon fruit beverages were investigated in order to establish an informative framework for the manufacturing of commercial dragon fruit beverages, focusing on health benefits and safety for consumers, and sensory appeal of the products.

Methods: This study employed various analytical methods to quantify some important phytochemical compounds in dragon fruit juice such as total and reducing sugars, vitamin C, betacyanins, anthocyanins, polyphenol, and so forth. This study also employed the Box-Behnken response surface experimental design to optimize various processing parameters for quality and consumer satisfaction, which include enzymatic pectin hydrolysis parameters and formulation for dragon fruit energy drink.

Results: The results from this study indicated a causal relationship between geological origin and some important characteristics of dragon fruit juice, emphasizing the need to track the source of fruits to ensure consistent quality of juice products. This study also systematically determined the impacts of various enzymatic hydrolysis, thermal sterilization, and formulation parameters on both nutrition content and sensory aspects of dragon fruit beverages, while also successfully optimized these parameters for the best outcomes.

Conclusion: This study had successfully achieved the objective of establishing a valuable framework for the manufacturing of commercial dragon fruit beverages, focusing on health benefits and safety for consumers, and sensory appeal of the products.

Recently, with the popularity of Internet of vehicles (IoV), there is an increasing market demand for integrating blockchain technology and smart contracts in electric vehicles. By utilizing distributed blockchain and smart contract technology, it provides data integrity preservation, traceability, and prevention of forgery. These features can be effectively used in the automated charging system. As a result, IoV can utilize blockchain and smart contract technologies to facilitate seamless payment for charging fees, tolls, parking fees, online shopping and other associated expenses without the need for intermediaries. However, since blockchain and smart contracts operate in an open internet environment, there is a risk of tampering with transaction records. Therefore, enhancing security becomes a crucial concern. The main aim of this study is to emphasize the growing significance of securing transactions and smart contracts in an open transmission environment to prevent potential damage or alteration.In order to achieve the implementation of secure smart contracts within a resource-constrained IoV, this study investigates various cryptographic mechanisms and realizes the elliptic curve cryptosystem (ECC) is widely recognized for providing strong security with shorter key lengths compared to other public key cryptography methods. This makes it ideal for environments with limited resources. Furthermore, in order to enhance the performance of smart contracts, this study proposes a cloud server architecture for parallel storage of smart contracts to improve access speed. Additionally, we introduce an automated trading framework for smart contracts that operates without human intervention.Finally, this study uses ECC to ensure the secure transmission of transaction data among the vehicle, base station, and cloud server, as well as to provide mutual verification of identities across all entities involved in the operation. As a result, this study proposes a secure architecture for blockchain and smart contracts that can autonomously initiate transactions while ensuring secure transmission and protection in the IoV.

Objective: Two walking tests including the six-minute walk test (6MWT) and the incremental shuttle walk test (ISWT) are widely used to evaluate functional ability in individuals with disease conditions. However, it remains unclear whether these walking tests effectively manifest clinical impairment in individuals with asymptomatic peripheral artery disease (PAD). We aimed (i) to compare the walking performance of individuals with and without asymptomatic PAD using the 6MWT and ISWT, and (ii) to investigate the correlation between ankle-brachial index and toe-brachial index (ABI-TBI) and the walking distance.

Methods: A cross-sectional, crossover, matched pairs design was employed in this study. Asymptomatic PAD was diagnosed using ABI-TBI measurements. Seventy-six participants (38 with asymptomatic PAD and 38 without PAD) were randomly ordered to perform the walking tests. During the 6MWT, participants walked along the 30-meter corridor at their self-selected pace for six minutes, and the six-minute walk distance (6MWD) covered was recorded. In the ISWT, participants walked at a 12 prescribed speed level, and the incremental shuttle walk distance (ISWD) covered was recorded.

Results: Result revealed no difference in 6MWD between individuals with asymptomatic PAD and without PAD (mean distance: 501.6 m vs 516.8 m, p = 0.24). Asymptomatic PAD individuals exhibited a significantly shorter ISWD than those without PAD (median distance: 270 m vs 340 m, p = 0.003). No participants reported any leg pain symptoms during the 6MWT and ISWT. A statistically significant positive correlation was observed between the right leg TBI and ISWD in all participants (r = 0.23, p = 0.04).

Conclusions: Individuals with asymptomatic PAD demonstrated poorer walking performance than those without PAD when assessed using ISWT but not the 6MWT. Asymptomatic PAD is also associated with diminished walking performance during the ISWT. Thus, ISWT may show the clinical impairment in this population.

As the critical components in hydrogen refueling, storage, and transportation systems, the degradation and failure of rubber O-ring seals under a high-pressure (HP) hydrogen environment (up to 100 MPa) directly affect hydrogen energy safety. Clarifying the interaction mechanism of hydrogen diffusion and the mechanical properties of rubber seals is essential for HP hydrogen infrastructure. A hydrogen diffusion-mechanical sequential numerical model is built to investigate the sealing performance and hydrogen diffusion behaviors of rubber seals using ABAQUS software. The effects of hydrogen swelling environmental pressure (5∼100 MPa) and stress-concentration gradient on mechanical and contact characteristics and hydrogen concentration distribution are analyzed for the rubber seals with/without backup rings, respectively. Furthermore, the orthogonal experimental and comprehensive frequency analysis methods are employed to evaluate the significance of the main structural and assembly parameters and obtain the optimal schemes of the rubber seals under the HP environment. The results show that the stress concentration and rubber extrusion easily occur at the sealing clearance of the O-rings with swelling after pre-compression and pressurization. The hydrogen diffusion of the O-ring is mainly driven by the concentration difference and stress gradient, with the former being the dominant factor. With the increase in the hydrogen pressure, the effective sealing rate along the sealing surface decreases sharply, and the non-uniformity of hydrogen concentration and the possibility of fatigue damage in the rubber O-rings increase. Two multi-objective optimization schemes (Ⅰ and Ⅱ) for the main structural and assembly parameters of rubber seals are obtained by intuitive analysis and comprehensive frequency analysis to improve the extrusion tendency and sealing reliability of rubber seals in the HP hydrogen environment.

This study employed a self-developed nanofluid/ultrasonic atomization minimal quantity lubrication system. The use of ultrasonic cavitation can effectively improve the accumulation of nanofluids via van der Waals force bonding and enhance their efficiency. This system is a high-speed milling manufacturing innovation in lubrication technology. Two types of nanoparticles (multiwalled carbon nanotubes and MoS₂ nanoparticles) were used to facilitate the mixing of nanofluids and their lubrication in the high-speed milling of 7075-T6 aluminum alloy. The surface roughness of each group of experimental results was used as the characteristic index. The surface roughness obtained from the optimization of the experimental results was 0.51 μm, while the worst group, which was based on the original orthogonal table, had a surface roughness of 1.05 μm, demonstrating an improvement of 51.43% in the quality characteristics. Results of comparative experiments demonstrated that using a nanofluid mixed with multiwalled carbon nanotubes and MoS₂ nanoparticles exerted better effects on surface roughness, tool wear, and workpiece burrs than using only nanofluids with single nanoparticles. This finding can be attributed to the mixed nanofluid, which simultaneously possesses the good grinding capability of MoS₂ and the excellent heat transfer property of multiwalled carbon nanotubes.