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Fe-Zn alloy, a new biodegradable material capable of reducing RoS and inhibiting oxidative stress

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Regenerative Biomaterials 2024年第2期3卷 114-122页

作者： Shuaikang Yang Weiqiang Wang Yanan Xu Yonghui yuan Shengzhi hao School of Materials Science and Engineering Dalian University of TechnologyDalian 116024PR China Clinical Research Center for Malignant Tumor of Liaoning Province Cancer Hospital of Dalian University of TechnologyShenyang 110042PR China

Fe-based biodegradable materials have attracted significant attention due to their exceptional mechanical properties and favorable biocompatibility.Currently,research on Fe-based materials mainly focuses on regulating the degradation rate.However,excessive release of Fe ions during material degrada-tion will induce the generation of reactive oxygen species(ROS),leading to oxidative stress and ferroptosis.Therefore,the con-trol of RoS release and the improvement of biocompatibility for Fe-based materials are very important.In this study,new Fe-Zn alloys were prepared by electrodeposition with the intention of using Zn as an antioxidant to reduce oxidative damage during alloy degradation.Initially,the impact of three potential degra-dation ions(Fe^(2+),Fe^(3+),Zn^(2+))from the Fe-Zn alloy on human endothelial cell(EC)activity and migration ability was investigated.Subsequently,cell adhesion,cell activity,ROs production and DNA damage were assessed at various locations surrounding the alloy.Finally,the influence of different concentrations of Zn^(2+) in the medium on cell viability and ROS production was evaluated.High levels of ROS exhibited evident toxic effects on ECs and promoted DNA damage.As an antioxidant,Zn?+effectively reduced ROS production around Fe and improved the cell viability on its surface at a concentration of 0.04 mmol/l.These findings demonstrate that Fe-Zn alloy can attenuate the ROS generated from Fe degradation therebyenhancingcytocompatibility.

关键词： biodegradable iron Fe-Zn alloys reactive oxygen species oxidative stress cytocompatibility

Chiral thermally activated delayed fluorescence materials for circularly polarized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1097-1116页

作者： Li yuan Yi-Pin Zhang You-xuan Zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chirality is an important natural characteristic of organic molecules,and chiral organic molecules have shown extensive application in areas such as pharmaceutical development and material science.Benefiting from the ability to achieve circularly polarized luminescence(CPL),chiral luminescent materials have shown potential applications in anti-glare display,optical communication and,3D display,etc.Due to the ability to harvest both singlet and triplet excitons by a fast reverse intersystem crossing process without involving noble metals,chiral thermally activated delayed fluorescence(TADF)materials with point chirality,axial chirality,planar chirality and helical chirality are regarded as the state-of-the-art materials for circularly polarized organic light-emitting diodes(CP-OLEDs).In recent years,the chiral TADF materials and CP-OLEDs have rapidly developed,but unfortunately,the dissymmetry factors(g)are far from the requirement of practical applications.The ideal emitters and devices should have both high efficiency and a g factor,or at least a balance between these two elements.This review gives an overview of recent progress in chiral TADF materials,with a particular focus on the chiral skeleton,CPL property and device performance.Furthermore,the molecular design concept,device structure and methods to improve the g factors of chiral materials and CP-OLEDs are also discussed.

关键词： chiral thermally activated delayed fluorescence material chiral skeleton circularly polarized luminescence circularly polarized organic light-emitting diodes dissymmetry factor

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FL-EASGD:Federated Learning Privacy Security Method Based on Homomorphic Encryption

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Computers, Materials & Continua 2024年第5期79卷 2361-2373页

作者： hao Sun Xiubo Chen Kaiguo yuan Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China

Federated learning ensures data privacy and security by sharing models among multiple computing nodes instead of plaintext data.However,there is still a potential risk of privacy leakage,for example,attackers can obtain the original data through model inference attacks.Therefore,safeguarding the privacy of model parameters becomes crucial.One proposed solution involves incorporating homomorphic encryption algorithms into the federated learning process.However,the existing federated learning privacy protection scheme based on homomorphic encryption will greatly reduce the efficiency and robustness when there are performance differences between parties or abnormal nodes.To solve the above problems,this paper proposes a privacy protection scheme named Federated Learning-Elastic Averaging Stochastic Gradient Descent(FL-EASGD)based on a fully homomorphic encryption algorithm.First,this paper introduces the homomorphic encryption algorithm into the FL-EASGD scheme to preventmodel plaintext leakage and realize privacy security in the process ofmodel aggregation.Second,this paper designs a robust model aggregation algorithm by adding time variables and constraint coefficients,which ensures the accuracy of model prediction while solving performance differences such as computation speed and node anomalies such as downtime of each participant.In addition,the scheme in this paper preserves the independent exploration of the local model by the nodes of each party,making the model more applicable to the local data distribution.Finally,experimental analysis shows that when there are abnormalities in the participants,the efficiency and accuracy of the whole protocol are not significantly affected.

关键词： Federated learning homomorphic encryption privacy security stochastic gradient descent

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： hao Zhou Bohan Jiao Zhaohui Dang Jianping yuan School of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple nanosatellites.First,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and cuboid.Second,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance constraints.Third,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s outputs.The closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning tree.Finally,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation mission.The simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system

Fractal Characteristics and Main Controlling Factors of High-Quality Tight Sandstone Reservoirs in the Southeastern Ordos Basin

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Journal of Earth Science 2024年第2期35卷 631-641页

作者： Ruilin hao Wenhui Huang Jiu Bo Li yuan Key Laboratory for Marine Reservoir Evolution and Hydrocarbon Abundance Mechanism School of Energy ResourcesChina University of GeosciencesMinistry of EducationBeijing100083China

Due to the complex conditions and strong heterogeneity of tight sandstone reservoirs,the reservoirs should be classified and the controlling factors of physical properties should be studied.Cast thin section observations,cathodoluminescence,scanning electron microscopy(SEM),X-ray diffraction(XRD),and high-pressure mercury injection(HPMI)were used to classify and optimize the reservoir.The Brooks-Corey model and stepwise regression were used to study the fractal dimension and main controlling factors of the physical properties of the high-quality reservoir.The results show that the reservoirs in the study area can be divided into four types,and the high-quality reservoir has the best physical properties and pore-throat characteristics.In the high-quality reservoir,the homogeneity of transitional pores was the best,followed by that of micropores,and the worst was mesopores.The porosity was controlled by depth and kaolinite.The model with standardized coefficients is y=12.454−0.778×(Depth)+0.395×(Kaolinite).The permeability was controlled by depth,illite/montmorillonite,and siliceous cement,and the model with standardized coefficients is y=1.689−0.683×(Depth)−0.395×(Illite/Montmorillonite)−0.337×(Siliceous Cement).The pore-throat evolutionary model shows that the early-middle diagenetic period was when the reservoir physical properties were at their best,and the kaolinite intercrystalline pores and residual intergranular pores were the most important.

关键词： fractal dimension main controlling factors stepwise regression high-quality tight sandstone reservoir Ordos Basin petroleum geolgoy

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Human brain organoid:trends,evolution,and remaining challenges

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Neural Regeneration Research 2024年第11期19卷 2387-2399页

作者： Minghui Li Yuhan yuan Zongkun Hou Shilei hao Liang Jin Bochu Wang Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqingChina Southwest Hospital/Southwest Eye Hospital Third Military Medical University(Army Medical University)ChongqingChina School of Biology and Engineering/School of Basic Medical Sciences Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and advancements in brain organoids,few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience.To identify and further facilitate the development of cerebral organoids,we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years.First,annual publications,countries/regions,organizations,journals,authors,co-citations,and keywords relating to brain organoids were identified.The hotspots in this field were also systematically identified.Subsequently,current applications for brain organoids in neuroscience,including human neural development,neural disorders,infectious diseases,regenerative medicine,drug discovery,and toxicity assessment studies,are comprehensively discussed.Towards that end,several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research.

关键词： bibliometric analysis brain organoids cerebral organoids global trends neuroscience

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UPLC-Q-TOF/MS-Based Serum Metabolomics Reveals Potential Anti-tumor Mechanism of Banxia Xiexin Decoction in Colorectal Cancer Mice

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Chinese Journal of Integrative Medicine 2024年第7期30卷 623-632页

作者： YUE Yin-zi LI Ming-xuan WANG Xiao-hui QIN yuan-yuan WANG Ya-hui TAN Jin-hua SU Lian-lin YAN Shuai Department of General Surgery Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine School of Pharmacy Nanjing University of Chinese Medicine Department of General Surgery Bayinguoleng Mongolian Autonomous Prefecture People's Hospital Department of Pharmacy Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine Department of Anorectal Surgery Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine

Objective: To clarify the potential mechanism of Banxia Xiexin Decoction(BXD) on colorectal cancer(CRC) from the perspective of metabolomics. Methods: Forty male C57BL/6 mice were randomly divided into normal control(NC), azoxymethane/dextran sulfate sodium(AOM/DSS) model, low-dose BXD(L-BXD), high-dose BXD(H-BXD) and mesalamine(MS) groups according to a random number table, 8 mice in each group. Colorectal cancer model was induced by AOM/DSS. BXD was administered daily at doses of 3.915(L-BXD) and 15.66 g/kg(H-BXD) by gavage for consecutive 21 days, and 100 mg/kg MS was used as positive control. Following the entire modeling cycle, colon length of mice was measured and quantity of colorectal tumors were counted. The spleen and thymus index were determined by calculating the spleen/thymus weight to body weight. Inflammatory cytokine and changes of serum metabolites were analyzed by enzyme-linked immunosorbent assay kits and ultra performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q/TOF-MS), respectively. Results: Notably, BXD supplementation protected against weight loss, mitigated tumor formation, and diminished histologic damage in mice treated with AOM/DSS(P<0.05 or P<0.01). Moreover, BXD suppressed expression of serum inflammatory enzymes, and improved the spleen and thymus index(P<0.05). Compared with the normal group, 102 kinds of differential metabolites were screened in the AOM/DSS group, including 48 potential biomarkers, involving 18 main metabolic pathways. Totally 18 potential biomarkers related to CRC were identified, and the anti-CRC mechanism of BXD was closely related to D-glutamine and D-glutamate metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, arginine biosynthesis, nitrogen metabolism and so on. Conclusion: BXD exerts partial protective effects on AOM/DSS-induced CRC by reducing inflammation, protecting organism immunity ability, and regulating amino acid metabolism.

关键词： colorectal cancer metabolomics ultra performance liquid chromatography-quadrupole/time-of-flight mass spectrometry azoxymethane dextran sulfate sodium Banxia Xiexin Decoction Chinese medicine

Atomistic understanding of rough surface on the interfacial friction behavior during the chemical mechanical polishing process of diamond

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Friction 2024年第6期12卷 1119-1132页

作者： Song yuan Xiaoguang GUO hao WANG Renke KANG Shang GAO State Key Laboratory of High-performance Precision Manufacturing Dalian University of TechnologyDalian 116024China

The roughness of the contact surface exerts a vital role in rubbing.It is still a significant challenge to understand the microscopic contact of the rough surface at the atomic level.Herein,the rough surface with a special root mean square(RMS)value is constructed by multivariate Weierstrass–Mandelbrot(W–M)function and the rubbing process during that the chemical mechanical polishing(CMP)process of diamond is mimicked utilizing the reactive force field molecular dynamics(ReaxFF MD)simulation.It is found that the contact area A/A0 is positively related with the load,and the friction force F depends on the number of interfacial bridge bonds.Increasing the surface roughness will increase the friction force and friction coefficient.The model with low roughness and high lubrication has less friction force,and the presence of polishing liquid molecules can decrease the friction force and friction coefficient.The RMS value and the degree of damage show a functional relationship with the applied load and lubrication,i.e.,the RMS value decreases more under larger load and higher lubrication,and the diamond substrate occurs severer damage under larger load and lower lubrication.This work will generate fresh insight into the understanding of the microscopic contact of the rough surface at the atomic level.

关键词： diamond random roughness reactive force field molecular dynamics(ReaxFF MD) friction Weierstrass-Mandelbrot(W-M)function chemical mechanical polishing(CMP)

Achieving high-efficient photocatalytic persulfate-activated degradation of tetracycline via carbon dots modified MIL-101(Fe)octahedrons

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Chinese Journal of Chemical Engineering 2024年第2期66卷 298-309页

作者： hao yuan Xinhai Sun Shuai Zhang Weilong Shi Feng Guo School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

The synergistic reaction of photocatalysis and advanced oxidation is a valid strategy for the degradation of harmful antibiotic wastewater.Herein,carbon dots(CDs)modified MIL-101(Fe)octahedrons to form CDs/MIL-101(Fe)composite photocatalyst was synthesized for visible light-driven photocatalytic/persulfate(PS)-activated tetracycline(TC)degradation.The electron spin resonance(ESR)spectra,scavenging experiment and electrochemical analysis were carried out to reveal that the high visible light-driven photocatalytic degradation activity of TC over CDs/MIL-101(Fe)photocatalysts is not only ascribed to the production of free active radicals in the CDs/MIL-101(Fe)/PS system(·OH,·SO_(4-),^(1)O_(2),h^(+)and·O_(2)^(-))but also attributed to the consumption of electrons caused by the PS,which can suppress the recombination of photo-generated carriers as well as strong light scattering and electron trapping effects of CDs.Finally,the possible degradation pathways were proposed by analyzing intermediates via liquid chromatography-mass spectrometry technique.This research presents a rational design conception to construct a CDs/PS-based photocatalysis/advanced oxidation technology with high-efficient degradation activity for the remediation of organic antibiotic pollutant wastewater and for the improvement of carrier transport kinetics of photocatalysts.

关键词： Carbon dots MIL-101(Fe) Photocatalytic Persulfate activation Tetracycline degradation

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