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Artificial bone materials are in great need due to a lot of bone injuries. Herein, collagen/nano-hydroxyapatite (Col/nHA, C-H) composite nanospheres were obtained by in-situ mineralization, and poly L-lactic acid/collagen/nano-hydroxyapatite (PLLA/Col/nHA, P-C-H) was further prepared by high-speed shear emulsification method. The interfacial properties and structure between PLLA and nHA are regulated by the adhesive property of Col. The morphology, structure and properties of P-C-H microsphere were characterized in detail by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and simulated degradation of PBS in vitro. The results show that C-H is uniformly distributed in P-C-H microspheres, and a mesoporous material with a "pomegranate" structure and a particle size of 5-30 μm is self-assembled based on C-H multiple composite microspheres. It is beneficial to the sustained-release degradation of P-C-H and the retention/release of Ca

The yield and quality of potatoes, an important staple crop, are seriously threatened by high temperature and drought stress. In order to deal with this adverse environment, plants have evolved a series of response mechanisms. However, the molecular mechanism of potato’s response to environmental changes at the translational level is still unclear. In this study, we performed transcriptome- and ribosome-profiling assays with potato seedlings growing under normal, drought, and high-temperature conditions to reveal the dynamic translational landscapes for the first time. The translational efficiency was significantly affected by drought and heat stress in potato. A relatively high correlation (0.88 and 0.82 for drought and heat stress, respectively) of the fold changes of gene expression was observed between the transcriptional level and translational level globally based on the ribosome-profiling and RNA-seq data. However, only 41.58% and 27.69% of the different expressed genes were shared by transcription and translation in drought and heat stress, respectively, suggesting that the transcription or translation process can be changed independently. In total, the translational efficiency of 151 (83 and 68 for drought and heat, respectively) genes was significantly changed. In addition, sequence features, including GC content, sequence length, and normalized minimal free energy, significantly affected the translational efficiencies of genes. In addition, 28,490 upstream open reading frames (uORFs) were detected on 6463 genes, with an average of 4.4 uORFs per gene and a median length of 100 bp. These uORFs significantly affected the translational efficiency of downstream major open reading frames (mORFs). These results provide new information and directions for analyzing the molecular regulatory network of potato seedlings in response to drought and heat stress.

3D flower-like nitrogen and sulfur co-doped carbon nanosheets (N,S-CNS) were prepared with tunable heteroatom doping and graphitic structures. An “adsorption–insertion” model was proposed for well explaining the potassium storage behaviors.

Introduction: Physical training is essential to physical fitness in freestyle skiers. The domain of stability in the technical movements is a determinant of the competition, always constantly improving. Objective: Develop a physical training program adapted to freestyle skiing. Methods: Twelve freestyle skiers were selected as volunteers for the experiment. This paper compares athletes’ physical qualities and individual abilities before and after physical training. Through recent research, the athletes’ physical condition was comprehensively evaluated to test the effectiveness of their physical training. results: Freestyle skiers showed good anaerobic fitness. A relationship was found between the maximum number of thrusts, the degree of spin in the air, the maximum power duration, and the power decay rate (P0.05). Conclusion: This paper systematically studies body composition, the center of gravity strength, anaerobic capacity, and balance in freestyle skiers. The results provide a good assessment of the effect of fitness training on freestyle ski athletes. These results have particular guiding significance for formulating and implementing training programs focused on the sport. Level of evidence II; Therapeutic studies - investigation of treatment outcomes. RESUMO Introdução: O treinamento físico é parte essencial da aptidão física em esquiadores de estilo livre. O domínio da estabilidade nos movimentos técnicos é determinante sobre as competições, estando sempre em constante aprimoramento. Objetivo: Elaborar um programa de treinamento físico adaptado ao esporte do esqui de estilo livre. Métodos: Selecionou-se 12 esquiadores de estilo livre como voluntários ao experimento. Este artigo compara as qualidades físicas e habilidades individuais dos atletas antes e depois do treinamento físico. Através de pesquisas recentes, avaliou-se de forma abrangente a condição física dos atletas para testar a eficácia de seu treinamento físico. Resultados: Os esquiadores de estilo livre apresentaram uma boa praticabilidade anaeróbica. Foi encontrada uma relação particular entre o número máximo de propulsões e o grau de giro no ar, a duração máxima da potência e a taxa de decaimento da potência (P0,05). Conclusão: Este artigo fornece um estudo sistemático da composição corporal, força do centro gravitacional, capacidade anaeróbica e equilíbrio em esquiadores de estilo livre. Os resultados proporcionam uma boa avaliação do efeito de treinamento de aptidão física nos atletas de esqui de estilo livre. Estes resultados têm um significado orientador particular para a formulação e implementação de programas de treinamento focados na modalidade. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento. RESUMEN Introducción: El entrenamiento físico es una parte esencial de la aptitud física en los esquiadores de estilo libre. El dominio de la estabilidad en los movimientos técnicos es determinante sobre las competiciones, estando siempre en constante mejora. Objetivo: Desarrollar un programa de entrenamiento físico adaptado al deporte del esquí de estilo libre. Métodos: Se seleccionaron doce esquiadores de estilo libre como voluntarios para el experimento. Este artículo compara las cualidades físicas y las capacidades individuales de los atletas antes y después del entrenamiento físico. Mediante una investigación reciente, se evaluó exhaustivamente la condición física de los atletas para comprobar la eficacia de su entrenamiento físico. Resultados: Los esquiadores de estilo libre mostraron una buena aptitud anaeróbica. Se encontró una relación particular entre el número máximo de empujes y el grado de giro en el aire, la duración de la potencia máxima y la tasa de disminución de la potencia (P0,05). Conclusión: Este artículo proporciona un estudio sistemático de la composición corporal, la fuerza gravitatoria central, la capacidad anaeróbica y el equilibrio en esquiadores de estilo libre. Los resultados proporcionan una buena evaluación del efecto del entrenamiento físico en los atletas de esquí de estilo libre. Estos resultados tienen una especial importancia orientativa para la formulación y aplicación de programas de entrenamiento centrados en este deporte. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

The state-of-art progress of alloy-type anodes for potassium-ion batteries and their K+ storage mechanism and structure-property relationship are summarized.

Signals from gyros and accelerometers in an inertial navigation system (INS) can be processed to obtain navigation information while its errors accumulate with time. A path with long‐term characteristics is more likely to encounter unpredictable dynamic conditions. To deal with such problems, this work improves the global static path‐planning algorithm based on the A* algorithm, and the local dynamic path‐planning algorithm based on dynamic window approach (DWA). In the global planning algorithm, the gravity index and the heading index are incorporated into the cost function of the A* algorithm to consider the mismatches and the deflection of the path. Furthermore, the search method of the A* algorithm is also improved. In the local planning algorithm, the motion model of the DWA algorithm is improved to a high‐precision model and expressed in a geographic coordinate system. Finally, the improved global static planning and local dynamic planning are combined as the global dynamic path‐planning algorithm of an underwater vehicle. The simulation results show that the global dynamic path‐planning algorithm proposed can realise obstacle‐free navigation of the underwater vehicle.

With climate change and global warming, there are extreme weather phenomena in some places. Excessive temperature can adversely affect room temperature vulcanized silicone rubber (RTV) insulators. Other factors such as air pollution, dust, fog, rain, ice and snow, and ultraviolet rays can cause damage to the surface hydrophobicity of the RTV surface and reduce its service life. Contamination from the above factors increases the risk of flashover and corona discharge, which can lead to accidents in the transmission system, resulting in economic loss or personal injury. In recent decades, scientists have investigated a variety of materials that can be compounded with RTV to improve their chemical and physical properties in order to extend the service life of RTV insulators. In this review, we conduct an extensive literature survey and summary on the development and application of RTV coated insulators.

Due to the large ionic radius and associated slow reaction kinetics of potassium ions, it is a major challenge to find suitable anode materials for potassium-ion batteries. Herein, we design porous antimony-based nanofibres via a simple, low-cost and large scalable method to promote the electrochemical performance of potassium-ion batteries. Unlike those traditionally treated in inert atmospheres, using the different decomposition processes of polyacrylonitrile and polyvinylpyrrolidone in air, we obtain antimony trioxide embedded in porous carbon nanofibres (Sb