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Compositional catalysts based on porous supports and incorporated catalytic nanoparticles have achieved great successes during the past decades. However, rational design of synergic catalysts and modulating the interactions between functional supports and catalytic sites are still far from being well developed. In this work, aiming at overcoming the difficulties of comprehensive screening of porous supports and correspondingly matched catalytic sites, a cationic porous aromatic framework as a capturing platform and polyoxometalate anions as conversion materials are separately designed, and their combination is modularly controlled. The resulting composites show higher catalytic activities than the corresponding conversion sites themselves. Notably, the resulting composites uncommonly exhibit increased surface area and enlarged pore openings after the incorporation of nanoparticles, and lead to the promotion of mass transfer within the porous supports. The emergence of a hierarchical structure with increased surface area induced by guest loading is desired in heterogeneous catalysis. The reciprocal modulation of both capture and conversion materials results in enhanced conversion and increased reaction rate, indicating the successful preparation of synergic catalysts by this separate design approach.

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Low intensity ultrasonic therapy is always an important research area of ultrasonic medicine. This review concentrates on low intensity ultrasound enhancing bactericidal action of antibiotics against bacteria in vitro and in vivo, including planktonic bacteria, bacterial biofilms, Chlamydia, and bacteria in implants. These literatures show that low intensity ultrasound alone is not effective in killing bacteria, while the combination of low intensity ultrasound and antibiotics is promising. Low intensity ultrasound facilitating antibiotic treatment is still in its infancy, and still requires a great deal of research in order to develop the technology on medical treatment scale.

We report the design and synthesis of cesium‐doped hydroxyapatite for direct and high‐yield conversion of biobased lactic acid to 2,3‐pentanedione (72.3 %). Cs species derived from CsNO3 at high temperature of calcination is introduced into the hydroxyapatite structure to regulate its acid–base properties. It is found that a balance of acid–base chemistry favors the condensation of lactic acid to 2,3‐pentanedione. As a result, the undesired reactions such as lactic acid dehydration, decarbonylation, and coking are suppressed. Instead, a concerted catalysis between surface basic site and acidic site for lactic acid condensation to 2,3‐pentanedione dominates on the cesium‐doped hydroxyapatite catalyst, leading to a highly selective process for direct conversion of bio‐lactic acid to 2,3‐pentanedione.

Interaction between humans and the gut microbiota is important for human physiology. Here, the gut microbiota was analyzed via metagenomic sequencing, and the fluctuations in the gut microbiota under the conditions of spaceflight were characterized. The composition and function of the gut microbiota were substantially affected by spaceflight; however, individual specificity was uncompromised. We further confirmed the species fluctuations and functional genes from both missions. Resistance and virulence genes in the gut microbiota were affected by spaceflight, but the species attributions remained stable. Spaceflight markedly affected the composition and function of the human gut microbiota, implying that the human gut microbiota is sensitive to spaceflight.

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