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Phase separation provides a general mechanism for the formation of biomolecular condensates, and it plays a vital role in regulating diverse cellular processes, including gene expression. Although the role of transcription factors and coactivators in regulating transcription has long been understood, how phase separation is involved in this process is just beginning to be explored. In this review, we highlight recent advance in elucidating the molecular mechanisms and functions of transcriptional condensates in gene expression control. We discuss the different condensates formed at each stage of the transcription cycle and how they are dynamically regulated in response to diverse cellular and extracellular cues that cause rapid changes in gene expression. Furthermore, we present new findings regarding the dysregulation of transcription condensates and their implications in human diseases.

In order to study the factors affecting the transmission performance of the steering gear used in agricultural intelligent cars, a small steering gear model is established by RecurDyn. Within the allowable range of the circumferential backlash of each gear group, the changes of different circumferential backlash are obtained by adjusting the tooth thickness of the gear group. The simulation of acceleration, deceleration and forward and reverse rotation of the steering gear model shows that when the circumferential backlash is 0.130 mm, the accuracy of the output gear 8 of the steering gear is relatively high and the return error is small. This research provides a theoretical basis for solving the driving accuracy problem of a smart car.

A polyethylenimine adjuvant modified by mannose, which may be used in the study of vaccine adjuvant, was prepared in this paper. Its structure was characterized by infrared spectroscopy and its micromorphology was observed by transmission electron microscopy. A series of mannose-modified polyvinylimine were prepared according to the molar ratio of primary amine groups between mannose and polyvinylimine, and their storage stability was observed at 4°C. In addition, the cytotoxicity of modified and unmodified polyethylenimine was also tested, and the results showed that the modified polyethylenimine was less toxic than unmodified polyethylenimine.

PP/FG composite materials were prepared by compressing moulding under high temperature through high-speed mixer, mixing mill and vulcanization machine taking PP as the matrix resin, FG as the thermal conductive filler, and NDZ-201 as the coupling agent. Effects of PP proportion, FG content and particle size on the thermal conductivity and mechanical properties of composite materials were studied. Results showed that PP proportion has little effect on the thermal conductivity of PP/FG composite materials, but it greatly affects the mechanical properties of the composite materials. Overall, the quality ratio of PP230 to K-4038 at 50:50 is more suitable. With the increasing of FG content, the thermal conductivity increases, and a significant critical value appears when the FG content is 50 wt%; The strength of the composite material first decreases and then increases, with an increase in modulus and a decrease in strain. As the FG particle size increases, the thermal conductivity of the composite material increases and the mechanical properties decrease.

This study describes a polymer potentially used as a vaccine adjuvant. We first synthesized a novel polyacrylic acid modified by perfluorinated butanol—a bioactive compound that is biocompatible. The main aim was to functionalize the polyacrylic acid by fluorine. This functionalization could offer a permanent graft by an esterification reaction. The chemical structure of the polymer has been characterized by the hydrogen nuclear magnetic resonance spectrum (1H-NMR) and fourier transform infrared spectrum (FT-IR). Thermal analysis showed that the esterification reaction was successful on the polyacrylic acid. Viscosity testing showed that the viscosity of the sample aqueous solution increases along with esterification. The surface tension of the polymer was also tested. The results show that the surface tension of the polyacrylic acid markedly decreased when modified by fluorine. Finally, the interaction of these materials with macrophages was tested on cell test. Results showed that the modified polyacrylic acid performed better improve the activation effect than pure polyacrylic acid in 1L-1β.

Poly (DL-lactide)/Poly (ethylene glycol) diblock copolymer is successfully synthesized with mPEG and DL-LA as main raw materials, and the residual monomers of the polymer were removed by recrystallization. FT-IR is used to characterize the structure of the polymer. Gas chromatography is used to determine the residual monomers and residual solvent of the polymer. The solubility of polymer in different solvents was determined, and the effect of different solvent systems on the removal of residual monomers in copolymer were discussed. The results showed that the Poly(DL-lactide)/Poly(ethylene glycol) diblock copolymer was recrystallized with acetone/ isopropyl ether solvent system has the best ability to remove residual monomers, and the residual monomers of the obtained polymer are less than 0.01 wt%, the total residual solvent is only 0.24 wt%, and the productivity is as high as 95.5 wt%.