润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展

随着现代化装备技术的快速发展,高端机械装备服役工况变得愈加复杂苛刻,磨损与腐蚀耦合损伤加速了高端机械装备运动部件的损伤失效,导致装备服役寿命大幅缩减,带来了严重的安全问题。润滑耐磨耐蚀功能一体化有机黏结涂层克服了润滑耐磨涂层和防腐蚀涂层的单一功能局限,为解决运动部件的磨损和腐蚀问题提供了有效方案。文中首先探讨了关键运动部件面临复杂服役工况的严峻挑战、材料磨损与腐蚀耦合的损伤机制;然后分别由黏结剂、填料和润滑剂3个方面介绍了目前润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展,对涂层的组成结构与力学性能、摩擦学性能、耐腐蚀性能间的构效关系进行了分析,并对不同涂层的局限性进行了概述;之后详细总结了润滑耐磨耐蚀功能一体化涂层的应用现状;最后对润滑耐磨耐蚀功能一体化涂层的发展方向进行展望。

Multimodal fusion recognition for digital twin

The digital twin is the concept of transcending reality,which is the reverse feedback from the real physical space to the virtual digital space.People hold great prospects for this emerging technology.In order to realize the upgrading of the digital twin industrial chain,it is urgent to introduce more modalities,such as vision,haptics,hearing and smell,into the virtual digital space,which assists physical entities and virtual objects in creating a closer connection.Therefore,perceptual understanding and object recognition have become an urgent hot topic in the digital twin.Existing surface material classification schemes often achieve recognition through machine learning or deep learning in a single modality,ignoring the complementarity between multiple modalities.In order to overcome this dilemma,we propose a multimodal fusion network in our article that combines two modalities,visual and haptic,for surface material recognition.On the one hand,the network makes full use of the potential correlations between multiple modalities to deeply mine the modal semantics and complete the data mapping.On the other hand,the network is extensible and can be used as a universal architecture to include more modalities.Experiments show that the constructed multimodal fusion network can achieve 99.42%classification accuracy while reducing complexity.

A new method for coseismic offset detection from GPS coordinate time series

Currently,the extraction of coseismic offset signals primarily relies on earthquake catalog data to determine the occurrence time of earthquakes.This is followed by the process of differencing the average GPS coordinate time series data,with a time interval of 3 to 5 days before and after the earthquake.In the face of the huge amount of GPS coordinate time series data today,the conventional approach of relying on earthquake catalog data to assist in obtaining coseismic offset signals has become increasingly burdensome.To address this problem,we propose a new method for automatically detecting coseismic offset signals in GPS coordinate time series without an extra earthquake catalog for reference.Firstly,we pre-process the GPS coordinate time series data for filtering out stations with significant observations missing and detecting and removing outliers.Secondly,we eliminate other signals and errors in the GPS coordinate time series,such as trend and seasonal signals,leaving the coseismic offset signals as the primary signal.The resulting coordinate time series is then modeled using the first-order difference and data stacking method.The modeling method enables automatic detection of the coseismic offset signals in the GPS coordinate time series.The aforementioned method is applied to automatically detect coseismic offset signals using simulated data and the Searles Valley GPS data in California,USA.The results demonstrate the efficacy of our proposed method,successfully detecting coseismic offsets from vast amounts of GPS coordinate time series data.

Users' Media Cloud Assisted D2D Communications for Distributed Caching Underlaying Cellular Network

In cellular networks, the proximity devices may share files directly without going through the e NBs, which is called Device-to-Device communications(D2D). It has been considered as a potential technological component for the next generation of communication. In this paper, we investigate a novel framework to distribute video files from some other proximity devices through users' media cloud assisted D2 D communication. The main contributions of this work lie in: 1) Providing an efficient algorithm Media Cloud Cluster Selecting Scheme(MCCSS) to achieve the reasonable cluster; 2) Distributing the optimum updating files to the cluster heads, in order to minimize the expected D2 D communication transmission hop for files; 3) Proposing a minimum the hop method, which can ensure the user obtain required file as soon as possible. Extensive simulation results have demonstrated the efficiency of the proposed scheme.

Cross-Modal Graph Semantic Communication Assisted by Generative AI in the Metaverse for 6G

Recently, the development of the Metaverse has become a frontier spotlight, which is an important demonstration of the integration innovation of advanced technologies in the Internet. Moreover, artificial intelligence (AI) and 6G communications will be widely used in our daily lives. However, the effective interactions with the representations of multimodal data among users via 6G communications is the main challenge in the Metaverse. In this work, we introduce an intelligent cross-modal graph semantic communication approach based on generative AI and 3-dimensional (3D) point clouds to improve the diversity of multimodal representations in the Metaverse. Using a graph neural network, multimodal data can be recorded by key semantic features related to the real scenarios. Then, we compress the semantic features using a graph transformer encoder at the transmitter, which can extract the semantic representations through the cross-modal attention mechanisms. Next, we leverage a graph semantic validation mechanism to guarantee the exactness of the overall data at the receiver. Furthermore, we adopt generative AI to regenerate multimodal data in virtual scenarios. Simultaneously, a novel 3D generative reconstruction network is constructed from the 3D point clouds, which can transfer the data from images to 3D models, and we infer the multimodal data into the 3D models to increase realism in virtual scenarios. Finally, the experiment results demonstrate that cross-modal graph semantic communication, assisted by generative AI, has substantial potential for enhancing user interactions in the 6G communications and Metaverse.

代谢改造酿酒酵母合成萜类化合物的研究进展

萜类化合物是一类种类繁多、功能多样的化合物,部分具有抗癌、增强免疫力等作用,具有良好的生物活性,在食品、保健品以及医疗等领域应用广泛。近年来,随着对萜类化合物生物合成途径研究的深入,研究人员采用代谢工程手段构建了多种萜类产物的高产酿酒酵母工程菌株,部分已经达到或者接近工业化生产水平。因此,采用合成生物学相关技术手段合成萜类化合物,有望取代化学合成或者传统的提取模式,成为天然萜类产物的新型生产方法。文中以常见的几种萜类产物为例,介绍并探讨萜类产物的生物合成策略以及合成生物学方面的研究进展。

Selenium-engineered bottom-up-synthesized lanthanide coordination nanoframeworks as efficiency X-ray-responsive radiosensitizers

Radiotherapy is one of the main therapeutic methods for cancers;however,nonselective killing of normal cells and tumor cells by X-ray inevitably results in toxicity and side effects.Developing low-toxicity and high-efficiency radiosensitizers to reduce the practical dose of X-ray is a promising approach to overcoming these side effects.Here,we report the use of carboxylatecontaining organic ligands to construct one-dimensional high-Z lanthanide chains for efficient response to X-ray.The onedimensional lanthanide chains are stacked through weak interactions to form coordination nanoframeworks in the presence of polyethylenimine(PEI).The morphology and activity of the synthesized nanoframeworks can be regulated through selenium atom engineering.This study presents a promising approach for effective radiotherapy through selenium-engineering stable lanthanide nanoframeworks with precise coordination structures as radiosensitizers to mitigate X-ray side effects.

A facile and general method for synthesis of antibiotic-free protein-based hydrogel:Wound dressing for the eradication of drug-resistant bacteria and biofilms

Antibacterial protein hydrogels are receiving increasing attention in the aspect of bacteria-infected-wound healing. However, bacterial drug resistance and biofilm infections lead to hard healing of wounds, thus the construction of biological agents that can overcome these issues is essential. Here, a simple and universal method to construct antibiotic-free protein hydrogel with excellent biocompatibility and superior antibacterial activity against drug-resistant bacteria and biofilms was developed. The green industrial microbicide tetrakis (hydroxymethyl) phosphonium sulfate (THPS) as cross-linking agent can be quickly cross-linked with model protein bovine serum albumin (BSA) to form antibacterial hydrogel through simple mixing without any other initiators, subsequently promoting drug-resistance bacteria-infected wound healing. This simple gelatinization strategy allows at least ten different proteins to form hydrogels (e.g. BSA, human serum albumin (HSA), egg albumin, chymotrypsin, trypsin, lysozyme, transferrin, myohemoglobin, hemoglobin, and phycocyanin) under the same conditions, showing prominent universality. Furthermore, drug-resistance bacteria and biofilm could be efficiently destroyed by the representative BSA hydrogel (B-Hydrogel) with antibacterial activity, overcoming biofilm-induced bacterial resistance. The in vivo study demonstrated that the B-Hydrogel as wound dressing can promote reepithelization to accelerate the healing of methicillin-resistant staphylococcus aureus (MRSA)-infected skin wounds without inducing significant side-effect. This readily accessible antibiotic-free protein-based hydrogel not only opens an avenue to provide a facile, feasible and general gelation strategy, but also exhibits promising application in hospital and community MRSA disinfection and treatment.

Substituent-regulated highly X-ray sensitive Os(Ⅵ)nitrido complex for low-toxicity radiotherapy

A high efficiency and low toxicity radiosensitizer,OsN(PhenOH)Cl_3,was designed and synthesized through substituent regulation.To the best of our knowledge,this is the first osmium-based coordination complex radiosensitizer.The experimental results shown that this radiosensitizer induced G2/M cell cycle arrest mainly through induction of intracellular ROS overproduction.

Progress in the Clinical Features and Pathogenesis of Abnormal Liver Enzymes in Coronavirus Disease 2019

With the rapid development of research on coronavirus disease 2019(COVID-19),more and more attention has been drawn to its damage to extrapulmonary organs.There are increasing lines of evidence showing that liver injury is closely related to the severity of COVID-19,which may have an adverse impact on the progression and prognosis of the patients.What is more,severe acute respiratory syndrome coronavirus-2 infection,cytokine storm,ischemia/hypoxia reperfusion injury,aggravation of the primary liver disease and drug-induced liver injury may all contribute to the hepatic damage in COVID-19 patients;although,the drug-induced liver injury,especially idiosyncratic drug-induced liver injury,requires further causality confirmation by the updated Roussel Uclaf Causality Assessment Method published in 2016.Up to now,there is no specific regimen for COVID-19,and COVID-19-related liver injury is mainly controlled by symptomatic and supportive treatment.Here,we review the clinical features of abnormal liver enzymes in COVID-19 and pathogenesis of COVID-19-related liver injury based on the current evidence,which may provide help for clinicians and researchers in exploring the pathogenesis and developing treatment strategies.

Atom engineering-regulated in situ transition of Cu(Ⅰ)-Cu(Ⅱ)for efficiently overcoming cancer drug resistance

The search of highly efficient drugs for overcoming cancer drug resistance continues to be a challenge for scientists.Constructing a metal drug based in situ oxidation-state transition system to disturb the redox balance in cancer cells is a promising approach for overcoming cancer drug resistance.Inspired by natural redox-active copper enzyme centers,we developed a Cu(Ⅰ)-Cu(Ⅱ) in situ transition system in this work.Through atom engineering,we fine-tuned the thermodynamic stability of this system to investigate its anticancer activity.The results indicated that the synthetic Cu(Ⅰ)-Cu(Ⅱ) system could under-go in situ transition in vitro and in vivo,to disrupt the intracellular redox balance and trigger mitochondrial dysfunction and G2/M arrest,leading to apoptosis and overcoming cancer drug resistance.This study presents a feasible way to overcome cancer drug resistance by designing an in situ oxidation-state transition metal drug system.

High-dimensional zinc porphyrin nanoframeworks as efficient radiosensitizers for cervical cancer

Radiotherapy is widely used clinically, but the toxic and side effects of nonselective killing of high-energy radiation limit its application. Finding biocompatible materials to assemble radiotherapy sensitizers and studying their sensitization patterns are of great significance for the clinical application. Here, biocompatible zinc porphyrin was chosen as sub-unit to construct various dimensional coordination frameworks. By employing top-down approach, suitable nanoframeworks with various dimensional zinc porphyrin were synthesized as radiosensitizers. The experimental data showed that high-dimensional zinc porphyrin nanoframeworks exhibit higher X-ray response performance.

Insights into the underlying mechanisms and clinical management of microscopic colitis in relation to other gastrointestinal disorders

Microscopic colitis(MC)is a chronic inflammatory disease of the large intestine and as a relatively late recognized condition,its relationship with other disorders of the gastrointestinal tract is gradually being understood and investigated.As a multifactorial disease,MC interacts with inflammatory bowel disease,celiac disease,and irritable bowel syndrome through genetic overlap,immunological factors,and gut microflora.The risk of colorectal cancer was significantly lower in MC,gastrointestinal infections increased the risk of developing MC,and there was an inverse association between Helicobacter pylori infection and MC.A variety of associations are found between MC and other gastrointestinal disorders,where aspects such as genetic effects,resemblance of immunological profiles,and intestinal microecology are potential mechanisms behind the relationships.Clinicians should be aware of these connections to achieve a better understanding and management of MC.