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Single thiolate replacement of metal nanoclusters

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Science China Chemistry 2024年第2期67卷 523-528页

作者： Ambreen Ambreen Yue Zhou Wanmiao Gu Qing You Liang Fang Guoqing Bian nan Yan nan Xia Zhikun Wu Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyInstitute of Solid State PhysicsHefei Institutes of Physical Science(HFIPS)Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230601China Institute of Physical Science and Information Technology Anhui UniversityHefei230601China

Surface thiolates play important roles in evincing the structures and properties of thiolated metal nanoclusters—one type of recently emerging inorganic-organic hybrids,and thus the thiolate substitution,especially single thiolate substitution,is highly desirable for subtly tailoring the structures and properties of metal ***,such a single-thiolate substituting is challenging,and its influence on the metal-metal and metal-sulfur bonds remains mysterious due to the absence of the singlethiolate-substituted ***,we developed a combined method,concurrently synthesized the single-thiolate-substituted nanocluster and its parent nanocluster,and successfully resolved their structures by single crystal X-ray crystallography,which reveals that the single thiolate substitute has an obvious influence on the metal-metal and metal-sulfur bond lengths although it has no effect on the absorption ***,the metal-metal and metal-sulfur bonds show various thermal extensibility and even the negative thermal expansion phenomena of the Au–S bond were observed in the single-thiolate-substituted *** bond length-related stability was also ***,this study highlights a novel synthesis method and offers novel structural insights and an in-depth structure-property correlation of thiolated metal nanoclusters.

关键词： metal nanoclusters single thiolate replacement thermal expansion stability intercluster interaction

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Genetic regulation of m^(6)A RNA methylation and its contribution in human complex diseases

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Science China(Life Sciences) 2024年第8期67卷 1591-1600页

作者： Kexuan Chen Jiuhong nan Xushen Xiong The Second Affiliated Hospital&Liangzhu Laboratory Zhejiang University School of MedicineHangzhou 311121China State Key Laboratory of Transvascular Implantation Devices The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 311121China

N6-methyladenosine(m^(6)A)has been established as the most prevalent chemical modification in message RNA(mRNA),playing an essential role in determining the fate of RNA *** of m^(6)A has been revealed to lead to abnormal physiological conditions and cause various types of human *** studies have delineated the genetic regulatory maps for m^(6)A methylation by mapping the quantitative trait loci of m^(6)A(m^(6)A-QTLs),thereby building up the regulatory circuits linking genetic variants,m^(6)A,and human complex ***,we review the recent discoveries concerning the genetic regulatory maps of m^(6)A,describing the methodological and technical details of m^(6)A-QTL identification,and introducing the key findings of the cis-and trans-acting drivers of m^(6)*** further delve into the tissue-and ethnicity-specificity of m^(6)A-QTL,the association with other molecular phenotypes in light of genetic regulation,the regulators underlying m^(6)A genetics,and importantly,the functional roles of m^(6)A in mediating human complex ***,we discuss potential research avenues that can accelerate the translation of m^(6)A genetics studies toward the development of therapies for human genetic diseases.

关键词： m^(6)A disease genetics m^(6)A-QTL GWAS

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Artificial intelligence for the detection of glaucoma with SD-OCT images:a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 408-419页

作者： nan-nan Shi Jing Li Guang-Hui Liu Ming-Fang Cao Department of Ophthalmology Affiliated People’s Hospital(Fujian Provincial People’s Hospital)Fujian University of Traditional Chinese MedicineFuzhou 350004Fujian ProvinceChina Eye Institute of Integrated Chinese and Western Medicine Fujian University of Traditional Chinese MedicineFuzhou 350004Fujian ProvinceChina

●AIM:To quantify the performance of artificial intelligence(AI)in detecting glaucoma with spectral-domain optical coherence tomography(SD-OCT)images.●METHODS:Electronic databases including PubMed,Embase,Scopus,ScienceDirect,ProQuest and Cochrane Library were searched before May 31,2023 which adopted AI for glaucoma detection with SD-OCT *** pieces of the literature were screened and extracted by two ***-analysis,Meta-regression,subgroup,and publication of bias were conducted by *** risk of bias assessment was performed in Revman5.4 using the QUADAS-2 tool.●RESULTS:Twenty studies and 51 models were selected for systematic review and *** pooled sensitivity and specificity were 0.91(95%CI:0.86–0.94,I2=94.67%),0.90(95%CI:0.87–0.92,I2=89.24%).The pooled positive likelihood ratio(PLR)and negative likelihood ratio(NLR)were 8.79(95%CI:6.93–11.15,I2=89.31%)and 0.11(95%CI:0.07–0.16,I2=95.25%).The pooled diagnostic odds ratio(DOR)and area under curve(AUC)were 83.58(95%CI:47.15–148.15,I2=100%)and 0.95(95%CI:0.93–0.97).There was no threshold effect(Spearman correlation coefficient=0.22,P>0.05).●CONCLUSION:There is a high accuracy for the detection of glaucoma with AI with SD-OCT *** application of AI-based algorithms allows together with“doctor+artificial intelligence”to improve the diagnosis of glaucoma.

关键词： artificial intelligence spectral-domain optical coherence tomography glaucoma Meta-analysis

Recent advances in the culture-independent discovery of natural products using metagenomic approaches

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Chinese Journal of Natural Medicines 2024年第2期22卷 100-111页

作者： SHEN Yiping LIU nan WANG Zongqiang Laboratory of Microbial Drug Discovery China Pharmaceutical UniversityNanjing 211198China

Natural products derived from bacterial sources have long been pivotal in the discovery of drug ***,the cultivation of only about 1%of bacteria in laboratory settings has left a significant portion of biosynthetic diversity hidden within the genomes of uncultured *** in sequencing technologies now enable the exploration of genetic material from these metagenomes through culture-independent *** approach involves extracting genetic sequences from environmental DNA and applying a hybrid methodology that combines functional screening,sequence tag-based homology screening,and bioinformatic-assisted chemical *** this process,numerous valuable natural products have been identified and synthesized from previously uncharted metagenomic *** paper provides an overview of the recent advancements in the utilization of culture-independent techniques for the discovery of novel biosynthetic gene clusters and bioactive small molecules within metagenomic libraries.

关键词： Metagenomics Culture-independent approach Natural product Functional screening Sequence tag-based homology screening Syn-BNP

Microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in Manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki nan Zhang Michael D.Gilchrist School of Mechanical and Materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2D computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： Micro feature shaping and electropolishing Micro mould tools Green electrolyte Demoulding micro patterns

Utilizing a metal-forging inspired chain combing strategy to enhance properties and expand applications of Nylon 66 plastic via heat inducing

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nano Research 2024年第3期17卷 2164-2171页

作者： Junyu Yang Jiangwei Zhang nan Wang Guangyuan Zhou Division of Energy Materials Daglian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Innovation Center of Energy Material and Chemistry College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China

The mechanical properties of engineering plastics can be enhanced through effective surface mechanical treatment(SMT),which can be applied to various types of engineering plastics,eliminating the limitations of conventional polymer processing and could potentially extend their applications and improve their performance and reliability as structural-functional *** by metal forging,this work proposes a simple and effective SMT strategy to enhance the mechanical properties of polyamide 66(PA66).Tensile tests have shown that SMTed PA66 samples exhibit significant improvements in both Young’s modulus and ultimate tensile strength(UTS),with a 2104 MPa Young’s modulus,almost double that of the pristine samples,and a 35.56%increase in UTS,reaching 183 ***,the modulus within the localized SMTed surface layer could reach up to 14 GPa,which is approximately 14 times higher than that of the pristine *** Vickers hardness within the localized SMTed surface layer can be doubled,reaching 10.72 Hv,and the crystallinity can increase by approximately 20%compared to the untreated ***,force field molecular dynamics(FFMD)simulations were conducted to investigate the ternary relationship between the SMT method,PA66’s molecular structure,and its *** combination of MD simulations and versatile structural characterizations provides evidence that the SMT method’s mechanism,under heat induction,results in a chain-combing procedure that changes the polymer’s molecular morphology microscopically and enhances its mechanical properties macroscopically.

关键词： Nylon 66 mechanical properties hardness crystallinity structural characterizations molecular dynamics simulation

Universal dynamic scaling and Contact dynamics in quenched quantum gases

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Frontiers of physics 2024年第2期19卷 213-220页

作者： Jia-nan Cui Zhengqiang Zhou Mingyuan Sun School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Lab of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Recently universal dynamic scaling is observed in several systems,which exhibit a spatiotemporal self-similar scaling behavior,analogous to the spatial scaling near phase *** latter one arises from the emergent continuous scaling *** by this,we investigate the possible relation between the scaling dynamics and the continuous scaling symmetry in this *** derive a theorem that the scaling invariance of the quenched Hamiltonian and the initial density matrix can lead to the universal dynamic *** is further demonstrated both in a two-body system analytically and in a many-body system *** the latter one,we calculate the dynamics of quantum gases quenched from the zero interaction to a finite interaction via the non-equilibrium high-temperature virial expansion.A dynamic scaling of the momentum distribution appears in certain momentum-time windows at unitarity as well as in the weak interacting ***,this universal scaling dynamics persists approximately with smaller scaling exponents even if the scaling symmetry is fairly *** findings may offer a new perspective to interpret the related *** also study the Contact dynamics in the BEC−BCS ***,the half-way time displays a maximum near unitarity while some damping oscillations occur on the BEC side due to the dimer state,which can be used to detect possible two-body bound states in experiments.

关键词： dynamic scaling Contact dynamics quantum gases cold atom quench dynamics virial expansion continuous scaling symmetry

Solution-processed rare-earth thulium oxide with high permittivity for low-voltage transistor and inverters applications

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Journal of Rare Earths 2024年第8期42卷 1604-1609,I0007页

作者： Daiming Liu Fei Wang Yongtao Zhang Ya'nan Ding Shandong Engineering Llaboratony for Preparation and Application of High performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science&TechnologyQingdao266061China College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao266590China

The use of high-permittivity(high-k) thin films as gate dielectrics is essential in the development of lowpower electronics,In this work,rare-earth thulium oxide(Tm_(2)O_(3)) thin films were prepared by a facile solution process and annealed at various temperatures from 400 to 700℃.The evolution of the physical and dielectric properties of Tm_(2)O_(3) thin film with annealing temperature was *** is demonstrated that the Tm_(2)O_(3) thin film annealed at 600℃ exhibits the optimal performance,including a low leakage current of 3×10^(-10) A/cm^(2),a large areal capacitance of 250 nF/cm^(2) at 100 Hz,and a high permittivity value of *** Tm_(2)O_(3) thin film as a gate insulator was integrated into the thin film transistor(TFT) employing In_(2)O_(3)-based semiconducting *** In_(2)O_(3) TFT with 600℃-annealed Tm_(2)O_(3) dielectric exhibits the superior perfo rmance,with a high I_(on)/I_(off) of 1.65×10^(7),a small subthre shold swing(SS) value of 0.2 V/dec,a V_(TH) of+1.8 V,and a mobility of 1.68 cm^(2)/(V·s).Furthermore,an inverter constructed by connecting the TFT with a resistor exhibits full-swing *** work provides a facile and appealing method for preparing the high-k Tm_(2)O_(3) thin films as alternative gate dielectrics with the potential for use in low-power electronics and logic circuit applications.

关键词： Rare earths Tm_(2)O_(3) Dielectric Transistor Inverter

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An ensemble and cost-sensitive learning-based root cause diagnosis scheme for wireless networks with spatially imbalanced user data distribution

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Science China(Information Sciences) 2024年第7期67卷 331-332页

作者： Qi WANG Zhiwen PAN nan LIU National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories

Root cause diagnosis, a key component of self-healing, plays a vital role in fault management. The spatially imbalanced network key performance indicators (KPIs) reported by users increase the difficulty of identifying root *** [1,2], the image inpainting technique is inspired to address issues caused by sparse reports across the coverage area.

关键词： Wireless networks

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