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With the increasing of bone diseases, bone substitute biomaterials have been urgently needed and recognized as effective therapeutic strategies for bone regeneration. However, the improper mechanical properties, uncontrolled curing time, and exothermic heat limited their clinical applications. Herein, a facile prepared injectable bone cement consisting of poly(methyl methacrylate), hydroxyapatite, curcumin, oxidized sodium alginate, and polyethylenimine is constructed. By taking advantage of the acid‐ and H2O2‐responsive covalent bonds, the resultant bone cement not only possessed superior compressive strength (>70 MPa), bending strength (>50 MPa), suitable curing time (9–14 min), and low exothermic heat (<42 oC), but also can release the drugs under the trigger of osteomyelitis microenvironment. Both at the cellular level and rat osteomyelitis models, the prepared bone cement exhibited excellent biocompatibility (cell survival rate: >97%; hemolysis ratio: <1.8%), anti‐bacterial (the lowest bacterial survival rate: ≈1.7%), anti‐inflammatory (the expressions of iNOS, CD86, TNF‐α, IL‐1β, and IL‐6 are significantly inhibited) and the ability to promote bone regeneration (proliferation of osteoblasts and inhibition of osteoclasts). It is believed that this work will provide a bioactive organic/inorganic composite material for bone tissue engineering, the distinctive human‐friendly low exothermic heat, and advantages of prodrug technique incorporated multi‐function integration endow them potential clinical application prospects. [ABSTRACT FROM AUTHOR]

A novel and convenient approach that combines high‐throughput experimentation (HTE) with machine learning (ML) technologies to achieve the first selective cross‐dimerization of sulfoxonium ylides via iridium catalysis is presented. A variety of valuable amide‐, ketone‐, ester‐, and N‐heterocycle‐substituted unsymmetrical E‐alkenes are synthesized in good yields with high stereoselectivities. This mild method avoids the use of diazo compounds and is characterized by simple operation, high step‐economy, and excellent chemoselectivity and functional group compatibility. The combined experimental and computational studies identify an amide‐sulfoxonium ylide as a carbene precursor. Furthermore, a comprehensive exploration of the reaction space is also performed (600 reactions) and a machine learning model for reaction yield prediction has been constructed. [ABSTRACT FROM AUTHOR]

Herein, a comprehensive computational study of the impact of solvation on the reduction reaction of CO2 to formic acid (HCOOH) and carbon monoxide on Pb(100) and Ag(100) surfaces is presented. Results further the understanding of how solvation phenomena influence the adsorption energies of reaction intermediates. We applied an explicit solvation scheme harnessing a combined density functional theory (DFT)/microkinetic modeling approach for the CO2 reduction reaction. This approach reveals high selectivities for CO formation at Ag and HCOOH formation on Pb, resolving the prior disparity between ab initio calculations and experimental observations. Furthermore, the detailed analysis of adsorption energies of relevant reaction intermediates shows that the total number of hydrogen bonds formed by HCOO plays a primary role for the adsorption strength of intermediates and the electrocatalytic activity. Results emphasize the importance of explicit solvation for adsorption and electrochemical reaction phenomena on metal surfaces. [ABSTRACT FROM AUTHOR]

Understanding how biotic and abiotic filters drive plant distributions is critical for informing restoration efforts of degraded lands. However, it remains unclear whether or not it is possible to develop efficient restoration strategies that are based on field investigations? Here, we conducted a field‐based investigation along a land degradation gradient on the Tibetan Plateau. Along this gradient, we compared species composition, Pianka's niche overlap, and total aboveground biomass among grasses, sedges, legumes, and forbs. We also used Faith's (1992) phylogenetic diversity index (PD) and the net relatedness index (NRI) to measure community phylogenetic patterns. To understand the effects of abiotic filtering, we measured soil pH, moisture, electrical conductivity, total soil organic carbon, microbial biomass carbon, and microbial biomass nitrogen. Our results show that grasses replaced sedges and mesoxerophytes replaced mesohydrophytes with increasing land degradation. We also found that niche overlap declined with increasing degradation intensity. Furthermore, grass biomass increased, while sedges and legumes decreased, and forb biomass showed a hump‐shaped relationship with degradation intensity. In addition, the communities transitioned from a clustered to a more random phylogenetic pattern. Soil conditions changed from acidic to alkaline and from fertile to harsh (p <.05). High niche overlap indicates a high biotic filtering at lightly degraded land where abiotic filtering is less stressful. However, when degradation is intense, abiotic filtering is apparent, as indicated by low levels of niche overlap. Overall, we suggest that distantly related, arid tolerant and hardy plants, and soil reclamation should be considered in degraded alpine lands restoration. [ABSTRACT FROM AUTHOR]