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RNA-Puzzles is a collective endeavor dedicated to the advancement and improvement of RNA three-dimensional structure prediction. With agreement from structural biologists, RNA structures are predicted by modeling groups before publication of the experimental structures. We report a large-scale set of predictions by 18 groups for 23 RNA-Puzzles: 4 RNA elements, 2 Aptamers, 4 Viral elements, 5 Ribozymes and 8 Riboswitches. We describe automatic assessment protocols for comparisons between prediction and experiment. Our analyses reveal some critical steps to be overcome to achieve good accuracy in modeling RNA structures: identification of helix-forming pairs and of non-Watson-Crick modules, correct coaxial stacking between helices and avoidance of entanglements. Three of the top four modeling groups in this round also ranked among the top four in the CASP15 contest.

Aerial recovery，dense flight and aerial refueling of unmanned aerial vehicles（UAVs）all involve flight stability and position control of the vehicle in a close-range interference flow field. In view of the background of UAV lateral recovery and release，adopting interference aerodynamic derivative model，the longitudinal small disturbance equation of motion of the vehicle in the close interference flow field is established，and the method using the rudder deflection to simulate the restoring force to achieve the longitudinal positional stability of the UAV is proposed. By using typical vehicle data，adopting the state space analysis method，the cost function is established，the optimal control design of pitch rudder deflection and variable thrust are completed，and the method of achieving the UAV longitudinal close-range-flight stability control is simulated and verified. The feasibility of close-range-flight stability is preliminarily verified.

Both drone swarm intensive flight and drone aerial recovery involve the stability problem of drone/carrier-aircraft flight in close range interference flow field. This paper proposes an aerodynamic derivative model for drone/carrier-aircraft interference based on the above application background, simplifies the longitudinal dynamic equations, and derives the simplified stability criteria for the drone. Numerical simulation and analysis indicate that this simplified criterion reflects the relationship between the drone's motion stability, aerodynamic characteristics, and interference flow field characteristics, and can be used for preliminary analysis and design of flight stability in interference flow fields. Numerical simulation also indicate that the down-wash flow can cause the drone to have short-period motion with slower convergence of amplitude, which increases the difficulty of achieving stable and controllable flight in the interference flow field.

Silicon is utilized as a functional material in various fields such as semiconductors, bio-medicine, and solar energy. To prepare Si materials, researchers have proposed methods including carbothermal reduction, hydrothermal reduction, and magnesiothermal reduction, but these strategies often involve high temperatures or unwanted by-products. Herein, we present a low-temperature ionic liquid reduction system to prepare Si nanospheres based on 1-butyl-3-methylimidazolium chloride-aluminum chloride ([Bmim]Cl-AlCl3). In this low-temperature solution system, AlCl3 not only absorbs the heat generated in the reaction, but also can be reduced by metallic Mg to active intermediates, which participate in the reduction of SiO2. Furthermore, spherical SiO2 can be gently reduced to spherical nano-Si with preserved morphology in the [Bmim]Cl-AlCl3 system. When the prepared Si nanosphere electrode is employed as the anode in lithium-ion batteries, it demonstrates an initial coulombic efficiency of 82.9% and a capacity retention of 94.2% after 100 cycles at 0.5 A g−1. Moreover, the SVC electrode, obtained by reducing SiO2@C, exhibits almost no capacity decay after 100 cycles and retains a specific capacity of 914 mA h g−1 after 600 cycles at 2 A g−1. This study provides an alternative, mild preparative route to Si-based functional materials with preserved morphology and components of the Si precursors. [ABSTRACT FROM AUTHOR]

Silicon-based anode materials experience significant volume changes and low conductivity during the lithiation process, which severely hinders their successful application in lithium-ion batteries. Reducing the size of silicon particles and effectively combining them with carbon-based materials are considered the main strategies to enhance the lithium-ion storage performance of silicon-based anodes. In this study, we employed a "bottom-up" strategy to synthesize Si@C anode materials by cross-linking octa-aminopropyl polyhedral oligomeric silsesquioxane (NH2-POSS) with terephthalaldehyde and subsequent high-temperature treatment and low-temperature liquid reduction. The obtained nanospheres consist of ultra-thin silicon stripes embedded in a continuous carbon framework, forming a carbon-protected silicon-based anode material suitable for lithium-ion batteries. The Si@C nanospheres exhibit excellent lithium-ion storage performance. After 1000 cycles at a current density of 0.5 A g−1, it retains an impressive capacity of 1363 mA h g−1, which is more than three times the theoretical capacity of graphite and 182% of the first cycle capacity after activation (750 mA h g−1). This work not only provides new possibilities for the application of POSS but also broadens the design and application of advanced silicon-based anode materials in the energy storage field. [ABSTRACT FROM AUTHOR]

Dissolvable polymeric microneedles have gained significant attention in recent years as a promising transdermal drug delivery method due to their simple fabrication and lack of medical waste after use. However, traditional polymeric microneedles possess several notable drawbacks, including insufficient mechanical strength, difficulty in effectively penetrating the skin barrier, limited drug loading capacity affecting therapeutic outcomes, and uncontrollable drug release rates leading to unstable efficacy. In this paper, a conductive polymer microneedle with an adjustable dissolution rate is proposed. The dissolution rate of microneedles can be adjusted by controlling the current so as to control the drug release rate and realize the controlled drug release truly. The PVA-Ag and PVP-Ag lidocaine-loaded microneedles demonstrated good puncture performance and nearly complete dissolution within 10 min in a simulated body fluid environment. The dissolution rate was significantly accelerated under electrical stimulation. The microneedles showed good biocompatibility, and under the application of a 3 V voltage, the drug delivery efficiency of PVP-Ag lidocaine microneedles reached 85% within 5 min, while PVA-Ag lidocaine microneedles achieved up to 90%. [ABSTRACT FROM AUTHOR]

Hexabromocyclododecane (HBCD), a brominated flame retardant, is linked to various health implications, including prostate cancer. This study explored the molecular mechanisms and potential biomarkers associated with HBCD exposure using data from the Comparative Toxicogenomics Database (CTD) and The Cancer Genome Atlas (TCGA). A total of 7,147 differentially expressed genes (DEGs) and 46 differentially expressed miRNAs were identified, with significant enrichment in cancer-related pathways and xenobiotic metabolism. Protein–protein interaction (PPI) network construction and enrichment analyses revealed four hub genes: DNAJC12, PKMYT1, RRM2, and SLC12A5. These genes displayed notable expression changes in response to HBCD exposure and were strongly correlated with survival outcomes in prostate cancer patients, as demonstrated by Cox regression and ROC curve analyses. Additionally, miRNA correlation analyses indicated robust positive associations, highlighting a coordinated regulatory network. Experimental expression analyses on HBCD-treated cell lines further validated these findings. This study sheds light on the significant impact of HBCD on gene and miRNA expression in prostate cancer, emphasizing the potential of the identified hub genes and miRNAs as prognostic biomarkers and therapeutic targets. By elucidating the pathways and regulatory networks influenced by HBCD, the findings provide a foundation for developing strategies to mitigate its carcinogenic effects and improve outcomes for prostate cancer patients. [ABSTRACT FROM AUTHOR]