Search

Ultra-high temperature ceramics (UHTCs) have been widely applied in many fields. In order to enhance the comprehensive properties of TaB2-based UHTCs, the first collaborative use of fine TaC particles and dispersed multi-walled carbon nanotubes (MWCNTs) was employed via spark plasma sintering (SPS) at 1700 °C. The derived UHTCs exhibited an average grain size of 1.3 μm, a relative density of 98.6%, an elastic modulus of 386.3 GPa, and a nano hardness of 21.7 GPa, leading to a greatly improved oxidation resistance with a lower linear ablation rate at −3.3 × 10−2 μm/s, and a markedly reinforced ablation resistance with mass ablation rate of −1.3 × 10−3 mg/(s·cm2). The enhanced ablation resistance was attributable to the physical pinning effect, sealing effect and self-healing effect. Thus, this study provides a potential strategy for preparation of UHTCs with bettered ablation resistance and physical properties. [ABSTRACT FROM AUTHOR]

Resveratrol, a phenylpropanoid compound, exhibits diverse pharmacological properties, making it a valuable candidate for health and disease management. However, the demand for resveratrol exceeds the capacity of plant extraction methods, necessitating alternative production strategies. Microbial synthesis offers several advantages over plant-based approaches and presents a promising alternative. Yarrowia lipolytica stands out among microbial hosts due to its safe nature, abundant acetyl-CoA and malonyl-CoA availability, and robust pentose phosphate pathway. This study aimed to engineer Y. lipolytica for resveratrol production. The resveratrol biosynthetic pathway was integrated into Y. lipolytica by adding genes encoding tyrosine ammonia lyase from Rhodotorula glutinis, 4-coumarate CoA ligase from Nicotiana tabacum, and stilbene synthase from Vitis vinifera. This resulted in the production of 14.3 mg/L resveratrol. A combination of endogenous and exogenous malonyl-CoA biosynthetic modules was introduced to enhance malonyl-CoA availability. This included genes encoding acetyl-CoA carboxylase 2 from Arabidopsis thaliana, malonyl-CoA synthase, and a malonate transporter protein from Bradyrhizobium diazoefficiens. These strategies increased resveratrol production to 51.8 mg/L. The further optimization of fermentation conditions and the utilization of sucrose as an effective carbon source in YP media enhanced the resveratrol concentration to 141 mg/L in flask fermentation. By combining these strategies, we achieved a titer of 400 mg/L resveratrol in a controlled fed-batch bioreactor. These findings demonstrate the efficacy of Y. lipolytica as a platform for the de novo production of resveratrol and highlight the importance of metabolic engineering, enhancing malonyl-CoA availability, and media optimization for improved resveratrol production. [ABSTRACT FROM AUTHOR]

Motivation Predicting protein–ligand binding affinity is crucial in new drug discovery and development. However, most existing models rely on acquiring 3D structures of elusive proteins. Combining amino acid sequences with ligand sequences and better highlighting active sites are also significant challenges. Results We propose an innovative neural network model called DEAttentionDTA, based on dynamic word embeddings and a self-attention mechanism, for predicting protein–ligand binding affinity. DEAttentionDTA takes the 1D sequence information of proteins as input, including the global sequence features of amino acids, local features of the active pocket site, and linear representation information of the ligand molecule in the SMILE format. These three linear sequences are fed into a dynamic word-embedding layer based on a 1D convolutional neural network for embedding encoding and are correlated through a self-attention mechanism. The output affinity prediction values are generated using a linear layer. We compared DEAttentionDTA with various mainstream tools and achieved significantly superior results on the same dataset. We then assessed the performance of this model in the p38 protein family. Availability and implementation The resource codes are available at https://github.com/whatamazing1/DEAttentionDTA. [ABSTRACT FROM AUTHOR]

Sustainable renewable polymer foam used as a lightweight porous skeleton for microwave absorption is a novel strategy that can effectively solve the problems of the large surface density, high additive amount, and narrow absorbing band of absorbing materials. In this article, novel renewable microwave-absorbing foams were prepared using Sapiumse biferum kernel oil-based polyurethane foam (BPUF) as porous matrix and Fe3O4-nanoparticles as magnetic absorbents. The microstructure and the microwave absorption performance, the structural effects on the properties, and electromagnetic mechanism of the magnetic BPUF (mBPUF) were systematically characterized and analyzed. The results show that the mBPUF displayed a porous hierarchical structure and was multi-interfacial, which provided a skeleton and matching layer for the Fe3O4 nanoparticles. The effective reflection loss (RL ≤ −10 dB) frequency of the mBPUF was from 4.16 GHz to 18 GHz with only 9 wt% content of Fe3O4 nanoparticles at a thickness of 1.5~5 mm. The surface density of the mBPUF coatings was less than 0.5 kg/cm2 at a thickness of 1.8 mm. The lightweight characteristics and broadband absorption were attributed to the porous hierarchical structures and the dielectric combined with the magnetic loss effect. It indicates that the mBPUF is a prospective broadband-absorbing material in the field of lightweight stealth materials. [ABSTRACT FROM AUTHOR]