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Menaquinone-7 (MK-7) possesses wide health and medical value, and the market demand for MK-7 has increased. Metabolic engineering for MK-7 production in Escherichia coli still remains challenging due to the characteristics of the competing quinone synthesis, and cells mainly synthesized menaquinones under anaerobic conditions. To increase the production of MK-7 in engineered E. coli strains under aerobic conditions, we divided the whole MK-7 biosynthetic pathway into three modules (MVA pathway, DHNA pathway, and MK-7 pathway) and systematically optimized each of them. First, by screening and enhancing Idi expression, the amounts of MK-7/DMK-7 increased significantly. AMBMP HCL Then, in the MK-7 pathway, by combinatorial overexpression of endogenous MenA and exogenous UbiE, and fine-tuning the expression of HepPPS, MenA, and UbiE, 70 μM MK-7 was achieved. Third, the DHNA synthetic pathway was enhanced, and 157 μM MK-7 was achieved. By the combinational metabolic engineering strategies and membrane engineering, an efficient metabolic engineered E. coli strain for MK-7 synthesis was developed, and 200 μM (129 mg/L) MK-7 was obtained in shake flask experiment, representing a 306-fold increase compared to the starting strain. In the scale-up fermentation, 2074 μM (1350 mg/L) MK-7 was achieved after 52 h fermentation with a productivity of 26 mg/L/h. This is the highest titer of MK-7 ever reported. This study offers an alternative method for MK-7 production from biorenewable feedstock (glucose) by engineered E. coli. The high titer of our process should make it a promising cost-effective resource for MK-7.The rapid progress in silicon carbide (SiC)-based technology for high-power applications expects an increasing operation temperature (up to 250 °C) and awaits reliable packaging materials to unleash their full power. Epoxy-based encapsulant materials failed to provide satisfactory protection under such high temperatures due to the intrinsic weakness of epoxy resins, despite their unmatched good adhesion and processability. Herein, we report a series of copolymers made by melt blending novolac cyanate ester and tetramethylbiphenyl epoxy (NCE/EP) that have demonstrated much superior high-temperature stability over current epoxies. Benefited from the aromatic, rigid backbone and the highly functional nature of the monomers, the highest values achieved for the copolymers are as follows glass-transition temperature (Tg) above 300 °C, decomposition onset above 400 °C, and char yield above 45% at 800 °C, which are among the highest of the known epoxy chemistry by far. Moreover, the high-temperature aging (250 °C) experiments showed much reduced mass loss of these copolymers compared to the traditional high-temperature epoxy and even the pure NCE in the long term by suppressing hydrolysis degradation mechanisms. The copolymer composition, i.e., NCE to EP ratio, has found to have profound impacts on the resin flowability, thermomechanical properties, moisture absorption, and dielectric properties, which are discussed in this paper with in-depth analysis on their structure-property relationships. The outstanding high-temperature stability, preferred and adjustable processability, and the dielectric properties of the reported NCE/EP copolymers will greatly stimulate further research to formulating robust epoxy molding compounds (EMCs) or underfill for packaging next-generation high-power electronics.As carriers of biomolecules (proteins, nucleic acids, and lipids) from parent cells, exosomes play a significant role in physiology and pathology. In any diseased state, the morphology of the released exosomes remained similar. The contents of exosomes change depending on the disease or its stage; thus, exosomes are generally considered as a “source of biomarkers”. Therefore, they are considered promising biomarkers for the diagnosis and prognosis of tumors. As natural delivery vehicles, exosomes can protect their cargo from immune clearance and deliver them to other cells through membrane fusion. After being genetically edited at the cell or exosome level, exosomes can be used for treatment with aptamers. Aptamers are short stretches of oligonucleotide sequences or short polypeptides that have been selected in vitro or in vivo, and have a wide range of targets and show excellent binding affinity and specificity. Aptamers have been widely used as molecular probes, and the combination of aptamers with exosomes has become a new direction for exosome-related research and therapeutic development. Here, we summarized various applications of exosomes and aptamers in cancer research, and further analyzed their combination as an “aptamer-exosome”. Finally, we propose future directions for the aptamer-exosome in the precise diagnosis or personalized treatment of cancer.To realize a wide range of applications using three-dimensional (3D) printing, it is urgent to develop 3D printing resins with different functions. However, the design freedom of the resin formulation is greatly limited to guarantee fast gelation during 3D printing. Herein, we report a reconfigurable polymer network that is compatible with digital light processing (DLP) 3D printing. The properties of the printed objects can be remanipulated by post-thermal treatment, during which the polymer network undergoes significant changes through the amidation of ester. The Young’s modulus could be significantly reduced by 50 times. Specifically, a well-printed rigid part can be completely turned into a low-viscosity liquid. This strategy decouples the printing process and the final material properties, providing an efficient approach to print various functional objects.Future electronic packaging technology requires semiconductor chips having a larger size and higher power for advanced applications, e.g., new energy conversion systems, electric vehicles, and data center servers, yet traditional thermal interface materials (TIMs) with a high thermal conductivity are generally stiff materials with weak joints, which cause the accumulated thermal stress to concentrate at the chip corners, leading to cracking and popcorn problems. To address such a critical challenge, herein for the first time we report a low-cost and high-performance porous copper (Cu)-indium (In) laminar structure as TIM, which can provide a superior thermal conductivity (50 W m-1 K-1) comparable to indium, yet the Young’s modulus (1.0 GPa) is an order of magnitude lower than indium, which is a state-of-the-art value. Additionally, the In-based intermetallic compound (IMC) joints enable more robust mechanical interconnection above the melting point of pure indium, providing better high-temperature performance.