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Science china chemistry 2024年第7期67卷 2325-2334页

作者： Xue Li Meng Kai Xu yuan Huang Tao cai Key Laboratory of Biomedical Polymers of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Wuhan University Shenzhen Research Institute Shenzhen 518057China

Despite the challenges that remain,the synergistic adjustment of various microstructures and photochemical parameters of graphitic carbon nitride(g-c_(3)N_(4))in photocatalytic reactions holds promises for improving catalytic efficiency and reducing energy ***,sulfur-doped and nitrogen-defective g-c_(3)N_(4)(n-Sc_(3)N_(x))nanosheets were designed and elaborately *** resultant n-Sc_(3)N_(x)possessed a precisely defined 2D layer structure with extensive porosity and incremental specific surface *** photoinduced electron transfer-reversible addition-fragmentation chain transfer(PET-RAFT)polymerization of vinyl monomers with low dispersity,excellent temporal control and high chain-end fidelity was achieved under mild blue light irradiation in a nondegassed *** to their ultrathin nanostructures with nitrogen defects and sulfur dopants,n-Sc_(3)N_(x)was capable of catalyzing RAFT polymerization in aqueous solutions at significantly accelerated rates,which were nearly 8 times faster compared to bulk g-c_(3)N_(4).The ease of separation and efficient reusability in subsequent polymerizations was enabled by the heterogeneous nature of n-Sc_(3)N_(x).The appeal of this approach was illustrated by the fact that utilizing a reusable and metal-free photocatalyst in aqueous environments allowed for the synthesis of polymers with molecular weight up to 300 kg mol^(-1) and a dispersity of 1.32.

关键词： graphitic carbon nitride nitrogen defects sulfur dopants PET-RAFT polymerization recyclability

Functionalized lipid nanoparticles modulate the blood-brain barrier and eliminate α-synuclein to repair dopamine neurons

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 120-135页

作者： Xiaomei Wu Renxiang yuan Yichong Xu Kai Wang Hong yuan Tingting Meng Fuqiang Hu Department of Pharmacy Ruijin HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200000China college of Pharmaceutical Science Zhejiang UniversityHangzhou 310058China Jinhua Institute of zhejiang University Jinhua 321299China

The challenge in the clinical treatment of Parkinson's disease lies in the lack of disease-modifying therapies that can halt or slow down the progression. Peptide drugs, such as exenatide (Exe), with potential disease-modifying efficacy, have difficulty in crossing the blood-brain barrier (BBB) due to their large molecular weight. Herein, we fabricate multi-functionalized lipid nanoparticles (LNP) Lpc-BoSA/cSO with BBB targeting, permeability-increasing and responsive release functions. Borneol is chemically bonded with stearic acid and, as one of the components of Lpc-BoSA/cSO, is used to increase BBB permeability. Immunofluorescence results of brain tissue of 15-month-old c57BL/6 mice show that Lpc-BoSA/cSO disperses across the BBB into brain parenchyma, and the amount is 4.21 times greater than that of conventional LNP. Motor symptoms of mice in Lpc-BoSA/cSO-Exe group are significantly improved, and the content of dopamine is 1.85 times (substantia nigra compacta) and 1.49 times (striatum) that of PD mice. α-Synuclein expression and Lewy bodies deposition are reduced to 51.85% and 44.72% of PD mice, respectively. Immunohistochemical mechanism studies show AKT expression in Lpc-BoSA/cSO-Exe is 4.23 times that of PD mice and GSK-3β expression is reduced to 18.41%. Lpc-BoSA/cSO-Exe could reduce the production of α-synuclein and Lewy bodies through AKT/GSK-3β pathway, and effectively prevent the progressive deterioration of Parkinson's disease. In summary, Lpc-BoSA/cSO-Exe increases the entry of exenatide into brain and promotes its clinical application for Parkinson's disease therapy.

关键词： Blood-brain barrier Lipid nanoparticles Brain delivery facilitation α-Symuclein Parkinson's disease

On the Difference Between the Skew-rank of an Oriented Graph and the Rank of Its Underlying Graph

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 129-136页

作者： Jia-min zhu Bo-jun yuan Yi Wang School of Mathematical Sciences Anhui UniversityHefei230601China School of Science Zhejiang University of Science and TechnologyHangzhou310023China

Let G be a simple graph and G~σ be the oriented graph with G as its underlying graph and orientation σ.The rank of the adjacency matrix of G is called the rank of G and is denoted by r(G).The rank of the skew-adjacency matrix of G~σ is called the skew-rank of G~σ and is denoted by sr(G~σ).Let V(G)be the vertex set and E(G) be the edge set of *** cyclomatic number of G,denoted by c(G),is equal to |E(G)|-|V(G)|+ω(G),where ω(G) is the number of the components of *** is proved for any oriented graph G~σ that-2c(G)≤sr(G~σ)-r(G)≤2c(G).In this paper,we prove that there is no oriented graph G~σwith sr(G~σ)-r(G)=2c(G)-1,and in addition,there are infinitely many oriented graphs G~σ with connected underlying graphs such that c(G)=k and sr(G~σ)-r(G)=2c(G)-l for every integers k,l satisfying 0 ≤l≤4k and l≠1.

关键词： cyclomatic number rank skew-rank

Visual observation of photonic Floquet–Bloch oscillations

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Light(Science & Applications) 2024年第5期13卷 921-929页

作者： zhen zhang yuan Li Xiankai Sun Xuewen Shu Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhanHubei 430074China Department of Electronic Engineering The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina

Bloch oscillations(BOs),an important transport phenomenon,have been studied extensively in static systems but remain mysterious in Floquet ***,by harnessing notions from photonic analogy,we propose a generalization of the existing BOs in photonic Floquet lattices,namely the“photonic Floquet–Bloch oscillations”,which refer to rescaled photonic Bloch oscillations with a period of extended least common multiple of the modulation period and the Bloch oscillation ***,we report the first visual observation of such photonic Floquet–Bloch oscillations(FBOs)by employing waveguide fluorescence *** significantly,the FBOs surpass the existing BOs in Floquet systems and exhibit exotic properties on their own,including fractal spectrum and fractional Floquet *** new transport mechanism offers an intriguing method of wave manipulation that may contribute to rapidly developing fields in photonics,condensed matter physics,and quantum physics.

关键词： Bloch analogy generalization

Recent Advances in Deciphering the Mechanisms and Biological Functions of DNA Demethylation

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chinese Journal of chemistry 2024年第6期42卷 645-651页

作者： Yang Feng Sheng-Jun chen Bi-Feng yuan Key Laboratory of Aquatic Product Processing Ministry of Agriculture and Rural AffairsNational R&D Center for Aquatic Product ProcessingSouth China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhouGuangdong510300 China School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhanHubei430071 China

5-Methylcytosine (5mc) is a dynamic and reversible epigenetic modification in genomic DNA of higher *** has been well-established that the demethylation of 5mc occurs through the ten-eleven translocation (TET)-mediated oxidation of 5mc followed by thymine DNA glycosylase (TDG)-initiated base excision repair (BER).Recent findings also have identified an alternative pathway of DNA *** this pathway,TET enzymes directly oxidize 5mc to form 5-formylcytosine (5fc) or 5-carboxylcytosine (5cac).These modified bases can undergo direct deformylation or decarboxylation,***,DNA demethylation can also occur through the deamination of 5mc and 5hmc,resulting in the production of thymine and 5-hydroxymethyluracil (5hmU),*** DNA demethylation pathways possess critical functional implications and roles in biological *** Recent Advances article will focus on the studies of mechanisms and biological functions of DNA demethylation,shedding light on the reversible nature of the epigenetic modification of 5mc.

关键词： Epigenetics DNA DNA methylation 5-Methylcytosine Demethylation Mechanisms Biological functions c—c bond cleavage Mass spectrometry

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： zi-Yi yuan Dong Bai zhen Wang zhong-zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China college of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev c 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Light-Activated Virtual Sensor Array with Machine Learning for Non-Invasive Diagnosis of coronary Heart Disease

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Nano-Micro Letters 2024年第12期16卷 427-448页

作者： Jiawang Hu Hao Qian Sanyang Han Ping zhang yuan Lu Department of chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China Department of cardiology Xuanwu HospitalCapital Medical UniversityBeijing 100053People’s Republic of China Department of cardiology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218People’s Republic of China Institute of Biopharmaceutical and Health Engineering Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055People’s Republic of China

Early non-invasive diagnosis of coronary heart disease(cHD)is ***,it is challenging to achieve accurate cHD diagnosis via detecting *** this work,heterostructured complexes of black phosphorus(BP)and two-dimensional carbide and nitride(MXene)with high gas sensitivity and photo responsiveness were formulated using a self-assembly strategy.A light-activated virtual sensor array(LAVSA)based on BP/Ti_(3)c_(2)Tx was prepared under photomodulation and further assembled into an instant gas sensing platform(IGSP).In addition,a machine learning(ML)algorithm was introduced to help the IGSP detect and recognize the signals of breath samples to diagnose *** to the synergistic effect of BP and Ti_(3)c_(2)Tx as well as photo excitation,the synthesized heterostructured complexes exhibited higher performance than pristine Ti_(3)c_(2)Tx,with a response value 26%higher than that of pristine Ti_(3)c_(2)*** addition,with the help of a pattern recognition algorithm,LAVSA successfully detected and identified 15 odor molecules affiliated with alcohols,ketones,aldehydes,esters,and ***,with the assistance of ML,the IGSP achieved 69.2%accuracy in detecting the breath odor of 45 volunteers from healthy people and cHD *** conclusion,an immediate,low-cost,and accurate prototype was designed and fabricated for the noninvasive diagnosis of cHD,which provided a generalized solution for diagnosing other diseases and other more complex application scenarios.

关键词： Black phosphorus/MXene heterostructures Light-activated virtual sensor array Diagnosis of coronary heart disease Machine learning

Synergistic effect of gradient zn content and multiscale particles on the mechanical properties of Al-zn-Mg-cu alloys with coupling distribution of coarse-fine grains

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： Liangliang yuan Mingxing Guo Yi Wang Yun Wang Linzhong zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0zn–1.5Mg–1.5cu–0.2Fe(wt%)alloy with high strength and *** the increase of zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–zn–Mg–cu alloys.

关键词： Al–zn–Mg–cu alloy iron-rich phase high formability microstructure mechanisms

Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting zha Hailu yuan zhen zheng He zhang Ministerial Key Laboratory of zNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers

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chinese Journal of chemical Engineering 2024年第4期68卷 8-15页

作者： Pengxing yuan Xiude Hu Jingjing Ma Tuo Guo Qingjie Guo college of chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China State Key Laboratory of High-efficiency Utilization of coal and Green chemical Engineering Ningxia UniversityYinchuan 750021China

Herein,the co-pyrolysis reaction characteristics of corn straw(cS)and bituminous coal in the presence of ilmenite oxygen carriers(Ocs)are investigated via thermogravimetry coupled with mass *** results reveal that the participation of Ocs weakens the devolatilization intensity of *** the cS blending ratio isc *** fitting results according to the coats-Redfern integral method show that the solid-solid interaction between Ocs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950c).The synergistic effect is most prominent at a 30%cS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).

关键词： Oxygen carrier co-pyrolysis Biomass coal