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This study investigates the dynamic behavior of a three-body tethered satellite system with a flexible tether, focusing on a scenario in which a payload is transported along the tether connecting two satellites. Traditional models use rigid tethers, limiting the analysis of complex dynamics such as tether deformation, slack, and rebound. To address these limitations, we employed the absolute nodal coordinate formulation (ANCF) to model the flexibility of the tether. We derived nonlinear equations of motion using Lagrange's equation and solved them using the Newmark time integration method to obtain the dynamic responses of the satellite system. Our findings revealed that the Coriolis effect caused significant deviations in the payload trajectory as its mass and speed increased, leading to greater tether deformation and slack, and potential system destabilization. Additionally, axial force fluctuations in the tether varied notably as the payload moved, transitioning between tensile and compressive states. This study provides a more accurate representation of three-body tethered satellite systems by incorporating tether flexibility, offering valuable insights into the dynamic behavior and stability of the system. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD), characterized by excessive liver fat accumulation, is a common liver disease linked to obesity, insulin resistance, and metabolic dysfunction. The lack of effective treatments against NAFLD has led to an increasing focus on alternative and natural remedies. Essential oils, extracted from a variety of plants, have drawn interest due to their high content of active compounds and potential functions to support liver health. Ginger essential oil, known for its anti-inflammatory, antioxidant, and cholesterol-lowering properties, promotes antioxidant enzymes and ameliorates liver fat accumulation in mice model of NAFLD. Nigella sativa oil with its diverse array of bioactive components, mitigates fatty liver by lowering tumor necrosis factor-alpha, malonaldehyde (MDA), and plasma lipids in vivo and in human trials that could contribute to NAFLD management. Garlic oil, rich in organosulfur compounds, has shown potential benefits in modulating oxidative stress and inflammation associated with NAFLD. Similarly, essential oils from turmeric, pepper, patchouli, and basil reduced lipid accumulation and inflammation and enhanced lipid metabolism in animal models of NAFLD. These findings underscore the use of essential oils as complementary medicines for NAFLD, opening avenues for further research and clinical applications. [ABSTRACT FROM AUTHOR]

This article investigates the source of booming noise emanating from the tailgate of an electric sport utility vehicle (SUV), along with proposed strategies to mitigate it. This annoying low-frequency booming noise, which significantly impacts interior sound quality, is less perceptible in conventional internal combustion engine vehicles. However, this noise is more readily detected in electric SUVs, highlighting the necessity for focused measures to reduce it. This study involved the measurement of booming noises during on-road vehicle tests to pinpoint their origins. Additionally, ODSs were extracted from the tailgate vibration signals to gain insight into its dynamic behavior. Modal tests were conducted on the tailgate to determine its dynamic characteristics and compared with driving test results to reveal the mechanism responsible for tailgate-induced booming noise. It was established that such noise is primarily due to the tailgate modes, resulting from a combination of rigid body motion in the fore-aft direction and deformation in the central section of the panel. An analytical model of the tailgate was developed using commercial finite-element analysis software to propose measures for reducing booming noise. Experimental findings validated this model's accuracy. Structural enhancements were implemented to enhance the panel stiffness and improve the connection between the vehicle and tailgate via bushings to reduce the booming noise resulting from tailgate motion. Under random force inputs, the analytical results demonstrated a 13.8% reduction in maximum deformation in the tailgate model in the improved structural configuration with increased panel stiffness. This study identifies the mechanism generating booming noise, establishes a practical and simple dynamic model, and proposes improvement measures aimed at reducing the booming noise. [ABSTRACT FROM AUTHOR]

This study presents a dynamic model of a passenger vehicle and analyzes its dynamic characteristics and responses. A dynamic vehicle model with seven degrees of freedom was established to analyze the behavior of a driving vehicle. The vehicle model had three degrees of freedom for the sprung mass's motion and four degrees for the unsprung masses. For this model, the equations of motion were derived using Lagrange's equation. To verify the model, the suspension deformations computed using the model were compared with those measured through three actual vehicle driving tests: the slalom, double lane change, and step steer tests. Furthermore, we investigated the effects of suspension stiffness, suspension damping, and anti-roll bar torsional stiffness on the dynamic characteristics and responses of the vehicle model. This study presented a new full-car model that can analyze a turning vehicle's behavior in response to changes in the steering angle input. The developed dynamic vehicle model may help vehicle designers predict the dynamic responses of a vehicle through simulation without performing a driving test. [ABSTRACT FROM AUTHOR]

Summary: Dry reforming of methane assisted by 5 wt% Ni‐X alloy catalysts (X: Co, Cu, Pd, and Rh) anchored on γ‐alumina is evaluated for comparing the synergetic effect of alloys at once as catalysts for dry reforming of methane at low temperatures of 400°C‐600°C. Characterization of catalysts confirms alloy formation, structural properties, and adsorption properties that affect the performance of each bimetallic catalyst. Catalytic performance is evaluated from the perspective of initial activity, syngas production and selectivity, long‐term stability, as well as energy efficiency at powder level not previously addressed, followed by post‐analysis for carbon formation. The results show that Ni‐Rh/Al2O3 and Ni‐Co/Al2O3 are highly active and stable during the reaction. Ni‐Rh/Al2O3 shows higher CH4 and CO2 conversions at 550°C as 32.71% and 84.69% of those at equilibrium, respectively. Similarly, CH4 and CO2 conversions of Ni‐Co/Al2O3 at 550°C are 26.17% and 71.76% of those at equilibrium. They exhibit better long‐term stability than a Ni monometallic catalyst, decreasing the degradation rate by 60% for Ni‐Rh/Al2O3 and 40% for Ni‐Co/Al2O3. Such improvement is even more pronounced when the temperature decreases from 500°C to 400°C, implying their potential as catalysts for dry reforming of methane at low temperatures. However, for every performance indicator, Ni‐Pd/Al2O3 and Ni‐Cu/Al2O3 exhibit low performance. These tendencies are mainly attributed to the synergetic effect of alloy and apparent activation energies for reactions. Based on such experimental results, it is discussed that Ni‐Rh/Al2O3 and Ni‐Co/Al2O3 are feasible and promising catalysts for dry reforming of methane even at low temperatures. [ABSTRACT FROM AUTHOR]

Molecular mechanisms underlying the decreased number of macrophages and T cells in the arteries of cholesterol-fed-rabbits following dexamethasone administration are unknown. We investigated the possibility that dexamethasone could affect activation of monocytic cells induced by oxygenated derivatives of cholesterol (oxysterols) using THP-1 monocyte/macrophage cells. 27-Hydroxycholesterol (27OHChol), an oxysterol elevated with hypercholesterolemia, enhanced production of CCL2, known as MCP1, chemokine from monocytes/macrophages and migration of the monocytic cells, but the CCL2 production and the cell migration were reduced by treatment with dexamethasone. Dexamethasone inhibited superproduction of CCL2 induced by 27OHChol plus LPS and attenuated transcription of matrix metalloproteinase 9 as well as secretion of its active gene product induced by 27OHChol. The drug downregulated cellular and surface levels of CD14 and blocked release of soluble CD14 without altering transcription of the gene. Dexamethasone also inhibited expression and phosphorylation of the NF-κB p65 subunit enhanced by 27OHChol. Collectively, these results indicate that dexamethasone inhibits activation of monocytes/macrophages in response to 27OHChol, thereby leading to decreased migration of inflammatory cells in milieu rich in oxygenated derivatives of cholesterol. [ABSTRACT FROM AUTHOR]

Novel 2 '-C-methyl-cyclopropyl-fused carbocyclic nucleosides as potential anti-HCV agents were stereoselectively synthesized, utilizing regioselective cleavage of the isopropylidene group and cyclic sulfate chemistry as key steps. [ABSTRACT FROM AUTHOR]

Novel apio carbocyclic nucleosides 18-21 were asymmetrically synthesized as potential antiviral and antitumor agent, starting from D-ribose employing aldol reaction, RCM reaction and Mitsunobu reaction as key reactions. [ABSTRACT FROM AUTHOR]

Introduction: Metabolism-associated fatty liver disease (MAFLD) is a global health concern because of its association with obesity, insulin resistance, and other metabolic abnormalities. Methylsulfonylmethane (MSM), an organic sulfur compound found in various plants and animals, exerts antioxidant and anti-inflammatory effects. Here, we aimed to assess the anti-obesity activity and autophagy-related mechanisms of Methylsulfonylmethane. Method: Human hepatoma (HepG2) cells treated with palmitic acid (PA) were used to examine the effects of MSM on autophagic clearance. To evaluate the anti-obesity effect of MSM, male C57/BL6 mice were fed a high-fat diet (HFD; 60% calories) and administered an oral dose of MSM (200 or 400 mg/kg/day). Moreover, we investigated the AMP-activated protein kinase (AMPK)/mechanistic target of rapamycin complex 1 (mTORC1)/UNC-51-like autophagy-activating kinase 1 (ULK1) signaling pathway to further determine the underlying action mechanism of MSM. Results: Methylsulfonylmethane treatment significantly mitigated PA-induced protein aggregation in human hepatoma HepG2 cells. Additionally, Methylsulfonylmethane treatment reversed the PA-induced impairment of autophagic flux. Methylsulfonylmethane also enhanced the insulin sensitivity and significantly suppressed the HFD-induced obesity and hepatic steatosis in mice. Western blotting revealed that Methylsulfonylmethane improved ubiquitinated protein clearance in HFD-induced fatty liver. Remarkably, Methylsulfonylmethane promoted the activation of AMPK and ULK1 and inhibited mTOR activity. Conclusion: Our study suggests that MSM ameliorates hepatic steatosis by enhancing the autophagic flux via an AMPK/mTOR/ULK1-dependent signaling pathway. These findings highlight the therapeutic potential of MSM for obesity-related MAFLD treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Han, Kim, Kim, Lee, Lyu, Kim, Shin, Kim, Kim and Park.)

Cases that are inoperable owing to poor preoperative conditions are sometimes encountered. However, there are some cases that are led to radical treatment by performing bridge therapy. Here, we presented a case of a patient with complex cardiac disease in an inoperable state who underwent bridging therapy that led to successful surgical treatment. A 73-year-old male who received hemodialysis treatment and had severe aortic valve stenosis and coronary artery disease planned surgical treatment. However, he was deemed inoperable owing to his low cardiac function and hemodynamic instability. Therefore, to escape from a fatal condition, we first performed balloon aortic valvuloplasty and percutaneous coronary intervention as palliative procedures. Subsequently, his cardiac function and hemodynamic stability remarkably improved; therefore, after 1 month, we performed a successful radical surgical treatment. Even in inoperable patients, bridging therapy leading to radical treatment is possible.