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The rational control of intrinsic defects in materials can significantly enhance their scientific and technological potentials, but it remains a long‐standing challenge in nanocrystal‐in‐glass composites (NGCs). Herein, a defect engineering strategy mediated by the mixed alkali effect is proposed and experimentally demonstrated for NGCs. Interestingly, the hybridization of large alkali ions can effectively increase the barrier of Li+ migration and reduce the Li‐related defects in LiNbO3 NGC. As a result, a novel LiNbO3 NGC with greatly reduced Li‐related defects, high crystallinity of over 60%, and excellent optical transmission are successfully fabricated. This unique NGC configuration facilitates efficient transverse second harmonic generation (TSHG) in a broad wavelength region. Based on the above effects, a standard TSHG device is fabricated and implemented to monitor ultrashort optical pulses with duration in the order of ≈10−13 s over a broad wavelength region, down to 780 nm. The proposed strategy not only provides a new idea for defect engineering in materials science but also has great significance for boosting the practical applications of NGCs in ultrashort optical pulse monitoring. [ABSTRACT FROM AUTHOR]

Under the new development philosophy of carbon peaking and carbon neutrality, CO2 and O2 in situ leaching (ISL) has been identified as a promising technique for uranium mining in China, not only because it solves carbon dioxide utilization and sequestration, but it also alleviates the environmental burden. However, significant challenges exist in assessment of CO2 footprint and water‐rock interactions, due to complex geochemical processes. Herein this study conducts a three‐dimensional, multicomponent reactive transport model (RTM) of a field‐scale CO2 and O2 ISL process at a typical sandstone‐hosted uranium deposit in Songliao Basin, China. Numerical simulations are performed to provide new insight into quantitative interpretation of the greenhouse gas (CO2) footprint and environmental impact (SO42–) of the CO2 and O2 ISL, considering the potential chemical reaction network for uranium recovery at the field scale. RTM results demonstrate that the fate of the CO2 could be summarized as injected CO2 dissolution, dissolved CO2 mineralization and storage of CO2 as a gas phase during the CO2 and O2 ISL process. Furthermore, compared to acid ISL, CO2 and O2 ISL has a potentially smaller environmental footprint, with 20% of SO42– concentration in the aquifer. The findings improve our fundamental understanding of carbon utilization in a long‐term CO2 and O2 ISL system and provide important environmental implications when considering complex geochemical processes. [ABSTRACT FROM AUTHOR]

Osteoarthritis is a chronic inflammatory disease characterized by cartilage degeneration. Anti‐inflammatory therapy has limited effects, and effective reduction of cartilage wear through lubrication is essential. In vivo stability and lubricity of commercial lubricants are insufficient, leading to failure of lubricating treatment and progression of osteoarthritis. To address these issues, new therapeutic methods combining anti‐inflammation and stable high‐performance lubrication are developed. Inspired by the sliding mechanism of snowboards, a "nano‐snowboard" by modifying molybdenum disulfide (MoS2) with a biomimetic phospholipid polymer poly (dopamine methacrylamide‐co‐2‐methacryloyloxyethyl phosphorylcholine) (PDMPC) and loading anti‐inflammatory drug diclofenac sodium (DS), namely MoS2‐PDMPC‐DS, has been synthesized. MoS2 with a 2D layered structure and photothermal properties, serves as solid lubricant and drug carrier. Meanwhile, the modification of PDMPC on the surface of MOS2 avoids the oxidative denaturation of MoS2 in a physiological environment, forming solid–liquid composite lubrication and improving the lubricity and stability of MoS2 in the joint cavity. In vitro and in vivo experiments show that MoS2‐PDMPC‐DS can stay in the joint cavity for more than one week and exert long‐lasting lubrication and anti‐inflammatory effects to treat osteoarthritis effectively. This solid–liquid composite lubricating nano‐snowboard provides a new idea for synergistic anti‐inflammatory and lubricating treatment of osteoarthritis. [ABSTRACT FROM AUTHOR]

Solid phase peptide synthesis (SPPS) strategy based on diaminodiacids had become an effective method for the synthesis of disulfide‐containing polypeptides. At present, it remains necessary to develop a diaminodiacid with more abundant chain structures to study the structure‐activity relationship. In this work, we developed a new type of diaminodiacids containing a six‐atom thioether (C−C‐S−C‐C−C, C−C‐C−S‐C−C) bridge. The key segment protected homo‐homocystine can be efficiently obtained by converting a side chain carboxyl group into a thiol group, which contribute to the facile and efficient synthesis of new diaminodiacid. With this diaminodiacid in hand, we successfully obtained tachyplesin containing new disulfide bond mimic by solid phase peptide synthesis. The tachyplesin analog not only has similar activity as natural counterpart, but also exhibits increased stability under reducing conditions. [ABSTRACT FROM AUTHOR]

Heterozygosity for missense mutations in Seipin, namely N88S and S90L, leads to a broad spectrum of motor neuropathy, while a number of loss-of-function mutations in Seipin are associated with the Berardinelli-Seip congenital generalized lipodystrophy type 2 ( CGL2, BSCL2), a condition that is characterized by severe lipoatrophy, insulin resistance, and intellectual impairment. The mechanisms by which Seipin mutations lead to motor neuropathy, lipodystrophy, and insulin resistance, and the role Seipin plays in central nervous system ( CNS) remain unknown. The goal of this study is to understand the functions of Seipin in the CNS using a loss-of-function approach, i.e. by knockdown ( KD) of Seipin gene expression. Excitatory post-synaptic currents ( EPSCs) were impaired in Seipin- KD neurons, while the inhibitory post-synaptic currents ( IPSCs) remained unaffected. Expression of a sh RNA-resistant human Seipin rescued the impairment of EPSC produced by Seipin KD. Furthermore, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid ( AMPA)-induced whole-cell currents were significantly reduced in Seipin KD neurons, which could be rescued by expression of a sh RNA-resistant human Seipin. Fluorescent imaging and biochemical studies revealed reduced level of surface AMPA receptors, while no obvious ultrastructural changes in the pre-synapse were found. These data suggest that Seipin regulates excitatory synaptic function through a post-synaptic mechanism. [ABSTRACT FROM AUTHOR]