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The woody bamboos (Bambusoideae) exhibit distinctive biological traits within Poaceae, such as highly lignified culms, rapid shoot growth, monocarpic mass flowering and nutlike or fleshy caryopses. Much of the remarkable morphological diversity across the subfamily exists within a single hexaploid clade, the paleotropical woody bamboos (PWB), making it ideal to investigate the factors underlying morphological evolution in woody bamboos. However, the origin and biogeographical history of PWB remain elusive, as does the effect of environmental factors on the evolution of their morphological characters. We generated a robust and time‐calibrated phylogeny of PWB using single nucleotide polymorphisms retrieved from optimized double digest restriction site associated DNA sequencing, and explored the evolutionary trends of habit, inflorescence, and caryopsis type in relation to environmental factors including climate, soil, and topography. We inferred that the PWB started to diversify across the Oligocene–Miocene boundary and formed four major clades, that is, Melocanninae, Racemobambosinae s.l. (comprising Dinochloinae, Greslanlinae, Racemobambosinae s.str. and Temburongiinae), Hickeliinae and Bambusinae s.l. (comprising Bambusinae s.str. plus Holttumochloinae). The ancestor of PWB was reconstructed as having erect habit, indeterminate inflorescence and basic caryopsis. The characters including climbing/scrambling habit, determinate inflorescence, and nucoid/bacoid caryopsis have since undergone multiple changes and reversals during the diversification of PWB. The evolution of all three traits was correlated with, and hence likely influenced by, aspects of climate, topography, and soil, with climate factors most strongly correlated with morphological traits, and soil factors least so. However, topography had more influence than climate or soil on the evolution of erect habit, whereas both factors had greater effect on the evolution of bacoid caryopsis than did soil. Our results provide novel insights into morphological diversity and adaptive evolution in bamboos for future ecological and evolutionary research. [ABSTRACT FROM AUTHOR]

Based on the establishment of peridynamic nonlocal porous media seepage model, several kernel functions reflecting the degree of nonlocal effect are introduced to improve the calculation accuracy, and the peridynamic permeability coefficients corresponding to different kernel functions are derived. In the two-dimensional seepage model, the Weibull-distributed permeability coefficient model and the fracture network seepage model are established to realize the heterogeneous seepage in porous media matrix and fracture, respectively, which make up for the shortage of classical peridynamic model that cannot well simulate the heterogeneous seepage in porous media such as rock and soil. Different kernel function models are tested in simulating one-dimensional seepage problems, and the influence of kernel functions on simulation results is analyzed. The results show that the improved model can well converge to the theoretical solution, and the polynomial kernel function has the highest convergence accuracy relative to other kernel functions. Then, the polynomial kernel function is introduced into the two-dimensional model, and the corresponding two-dimensional permeability coefficient is derived. The proposed heterogeneous seepage model is employed in the simulation of two-dimensional seepage in porous media with and without fracture, and the simulation results show that the proposed model can well simulate the heterogeneous seepage process in rock materials, proposing a wide application prospect in porous media seepage simulation.

Many examples of phenotypic modifications resulting from high‐elevation adaptation have been documented, however, the underlying processes responsible for these modifications and whether the continuity of the adaptation process remain elusive, particularly in plants. The alpine plants distributed along wide elevational gradients provide an ideal system to address this question. Here, we collected transcriptomes from multiple tissues of three species with different elevations (~1500, ~2500, and ~3600 m in the Hengduan Mountains, Southwest China) in two genera Fargesia and Yushania of alpine bamboos, respectively, and conducted evolutionary and expressional analyses. Results showed that high‐elevation adaptation emerged earlier in the evolutionary history of both genera and evolved continuously as the elevation increased. Moreover, convergence of genetic changes was observed in the two genera, with amounts of candidate genes responsible for high‐elevation adaptation identified under positive selection. Overall, our study provides an empirical example and valuable genetic resource for further investigation of high‐elevation adaptation in plants and sheds new light on how plants adapting to high‐elevation environments in a biodiversity hotspot. [ABSTRACT FROM AUTHOR]

Compatibilization of immiscible polymer blends is by far the most general and efficient strategy to convert multiphase polymer blends with poor miscibility into high performance polymer alloys. The concept and necessity of compatibilization of immiscible polymer blends were analyzed. Various compatibilization methods were introduced to improve the miscibility of polymer blends, including the addition of block or graft copolymers, reactive polymers, low molecular weight chemical compound and functionalized nanoparticles, etc. In addition, the development of compatibilization methods was reviewed and the effect of compatibilization on the phase morphology and final properties of the blends was discussed, such as mechanical properties, thermal properties, electrical properties, etc. Finally, it was proposed that nanoparticle compatibilization will become a popular method in the field of blend compatibilization. This method not only can increase the capacity, but also increase the mechanical strength and possibly bring new properties to the blend.

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Helicobacter pylori (HP) infections affect approximately one-third of children worldwide. In China, the incidence of HP infection in children ranges from approximately 30% to 60%. In addition to damaging the gastrointestinal tract mucosa, HP infection in children can negatively affect their growth and development, hematology, respiratory and hepatobiliary system, skin, nutritional metabolism, and autoimmune system. However, the rate of HP eradication also fell considerably from the previous rate due to the presence of drug-resistant HP strains and the limited types of antibiotics that can be used in young patients. Vitamin D3 (VitD3) is a steroid hormone that can reduce inflammation in the stomach mucosa induced by HP and can alleviate and eradicate HP through a variety of pathways and mechanisms, including immune regulation and the stimulation of antimicrobial peptide (AMP) secretion and Ca2+ influx, to reestablish lysosomal acidification; thus, these results provide new strategies and ideas for the eradication of drug-resistant HP strains. [ABSTRACT FROM AUTHOR]