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Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

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Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi Liu Wenjie Xu Shichao Xu Haifeng wu Baoli Zhang Li Song zhen-Gang Wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions

MOF-mediated synthesis of novel PtFeCoNiMn high-entropy nanoalloy as bifunctional oxygen electrocatalysts for zinc-air battery

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Nano Research 2024年第6期17卷 5288-5297页

作者： Mingkuan Xie Xin Xiao Duojie wu Cheng zhen Chunsheng wu Wenjuan Wang Hao Nian Fayan Li Meng Danny Gu Qiang Xu Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) Shenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL) Shenzhen 518055China Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional *** electronic structure regulation of HEAs plays a pivotal role in enhancing their elctrocatalytic ***,PtFeCoNiMn nanoparticles(NPs)with subtle lattice distortions are constructed on metal-organic framework-derived nitrogen-doped carbon by an ultra-rapid Joule heating *** to the modulated electronic structure and the inherent cocktail effect of HEAs,the as-synthesized PtFeCoNiMn/NC exhibits superior bifunctional electrocatalytic performance with a positive half-wave potential of 0.863 V *** hydrogen electrode(RHE)for oxygen reduction reaction and a low overpotential of 357 mV at 10 mA·cm^(-2)for oxygen evolution *** assembled quasi-solid-state zinc-air battery using PtFeCoNiMn/NC as air electrode shows a high peak power density of 192.16 mW·cm^(-2),low charge−discharge voltage gap,and excellent durability over 500 cycles at 5 mA·cm^(-2).This work demonstrates an effective route for rational design of bifunctional nanostructured HEA electrocatalysts with favorable electronic structures,and opens up a fascinating directions for energy storage and conversion,and beyond.

关键词： oxygen reduction reaction oxygen evolution reaction high-entropy nano-alloy zinc-air battery

Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy

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Journal of Central South University 2024年第7期31卷 2181-2193页

作者： ZHANG Tao QIN zhen-yang GONG Hai wu Yun-xin CHEN Xin Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Welding and Additive Manufacturing Centre Cranfield UniversityBedfordMK430ALUK

Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu ***,inferior mechanical properties of WAAM deposited material restrict its industrial ***-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this *** effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 *** ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited *** cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the *** cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 *** strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening.

关键词： wire-arc additive manufacture inter-layer cold rolling thermal-mechanical treatment microstructure mechanical properties strengthening mechanism

A compact multi-pixel superconducting nanowire single-photon detector array supporting gigabit space-to-ground communications

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Light(Science & Applications) 2024年第2期13卷 254-266页

作者： Hao Hao Qing-Yuan Zhao Yang-Hui Huang Jie Deng Fan Yang Sai-Ying ru zhen Liu Chao Wan Hao Liu Zhi-Jian Li Hua-Bing Wang Xue-Cou Tu La-Bao Zhang Xiao-Qing Jia Xing-Long wu Jian Chen Lin Kang Pei-Heng wu Research Institute of Superconductor Electronics(RISE) School of Electronic Science and EngineeringNanjing UniversityNanjingJiangsu 210023China Purple Mountain Laboratories NanjingJiangsu 211111China Hefei National Laboratory HefeiAnhui 230088China National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210023China

Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space *** achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel,a comprehensive design of a multi-functional detector is *** this study,we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency(91.6%),high photon counting rate(1.61 Gcps),large dynamic range for resolving different photon numbers(1-24),and four-quadrant position sensing function all within one ***,we have constructed a communication testbed to validate the advantages offered by such an *** 8-PPM(pulse position modulation)format communication experiments,we have achieved an impressive maximum data rate of 1.5 Gbps,demonstrating sensitivities surpassing previous benchmarks at respective *** incorporating photon number information into error correction codes,the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation ***,preliminary beam tracking tests were conducted through open-loop scanning techniques,which revealed clear quantitative dependence indicating sensitivity variations based on beam *** on the device characterizations and communication results,we anticipate that this device architecture,along with its corresponding signal processing and coding techniques,will be applicable in future space-to-ground communication tasks.

关键词： photon supporting correction

Patient-derived induced pluripotent stem cells with a MERTK mutation exhibit cell junction abnormalities and aberrant cellular differentiation potential

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World Journal of Stem Cells 2024年第5期16卷 512-524页

作者： Hang Zhang Ling-Zi wu zhen-Yu Liu Zi-Bing Jin Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100730China

BACKGROUND Human induced pluripotent stem cell(hiPSC)technology is a valuable tool for generating patient-specific stem cells,facilitating disease modeling,and invest-igating disease ***,iPSCs carrying specific mutations may limit their clinical applications due to certain inherent *** To investigate the impact of MERTK mutations on hiPSCs and determine whether hiPSC-derived extracellular vesicles(EVs)influence anomalous cell junction and differentiation *** We employed a non-integrating reprogramming technique to generate peripheral blood-derived hiPSCs with and hiPSCs without a MERTK ***-somal karyotype analysis,flow cytometry,and immunofluorescent staining were utilized for hiPSC *** and proteomics were employed to elucidate the expression patterns associated with cell junction abnormalities and cellular differentiation ***,EVs were isolated from the supernatant,and their RNA and protein cargos were examined to investigate the involvement of hiPSC-derived EVs in stem cell junction and *** The generated hiPSCs,both with and without a MERTK mutation,exhibited normal karyotype and expressed pluripotency markers;however,hiPSCs with a MERTK mutation demonstrated anomalous adhesion capability and differentiation potential,as confirmed by transcriptomic and proteomic ***,hiPSC-derived EVs were involved in various biological processes,including cell junction and *** HiPSCs with a MERTK mutation displayed altered junction characteristics and aberrant differentiation ***,hiPSC-derived EVs played a regulatory role in various biological processes,including cell junction and differentiation.

关键词： Cell junction Cellular differentiation Extracellular vesicle Human induced pluripotent stem cells Transcriptomics Proteomics

Quality of life after pancreatic surgery

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World Journal of Gastroenterology 2024年第8期30卷 943-955页

作者： Shi-zhen Li Ting-Ting zhen Yi wu Min Wang Ting-Ting Qin Hang Zhang Ren-Yi Qin Department of Biliary-Pancreatic Surgery Affiliated Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic surgery is challenging owing to the anatomical characteristics of the *** attention has been paid to changes in quality of life(QOL)after pancreatic *** To summarize and analyze current research results on QOL after pancreatic *** A systematic search of the literature available on PubMed and EMBASE was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** studies were identified by screening the references of retrieved *** on patients’QOL after pancreatic surgery published after January 1,2012,were *** included prospective and retrospective studies on patients'QOL after several types of pancreatic *** results of these primary studies were summarized *** A total of 45 articles were included in the study,of which 13 were related to pancreaticoduodenectomy(PD),seven to duodenum-preserving pancreatic head resection(DPPHR),nine to distal pancreatectomy(DP),two to central pancre-atectomy(CP),and 14 to total pancreatectomy(TP).Some studies showed that 3-6 months were needed for QOL recovery after PD,whereas others showed that 6-12 months was more *** TP and PD had similar influences on QOL,patients needed longer to recover to preoperative or baseline levels after *** QOL was better after DPPHR than ***,the superiority of the QOL between patients who underwent CP and PD remains *** decrease in exocrine and endocrine functions postoperatively was the main factor affecting the *** invasive surgery could improve patients’QOL in the early Core Tip:This review summarizes and analyzes current research results on quality of life(QOL)after pancreatic *** article covers the discussion and analysis of the QOL of various pancreatic *** kind of surgical procedure has better QOL is *** long-term benefits on QOL of minimally invasive su

关键词： Quality of life Pancreaticoduodenectomy Duodenum-preserving pancreatic head resection Distal pancreatectomy Central pancreatectomy Total pancreatectomy

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed Chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-Hao Wang rui Qiu An-Kang Hu Ye-Qi Liu zhen wu Hui Zhang Jun-Li Li Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint Institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Strengthening effect of prefabrication(10-12)tensile twinning on AZ80+0.4%Ce magnesium alloy and inhibition mechanism of discontinuous precipitation

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Journal of Magnesium and Alloys 2024年第5期12卷 1918-1930页

作者： zhen Wang Xi Zhao Zhimin Zhang Yaojin wu Kai Chen Xianwei Ren Dengkui Wang Wei Wang School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan 030051China

This paper provided an effective method to further improve the mechanical properties of the AZ80+0.4%Ce magnesium alloy wheel *** effect of high strength and ductility was obtained with a yield strength of 295.36 MPa,an elongation of 10%,by the combination of pre-deformation(7%deformation)and two-stage aging treatment(120℃/9 h+175℃/24 h).The evolution of the microstructure and properties of the alloy was explored under the coupling conditions of different pre-deformation degrees and multi-stage *** results show that,pre-deformation introduced a large number of(1012)tensile twinning and dislocations,which greatly promoted the probability of continuous precipitates(CPs)*** the contrary,the discontinuous precipitates(DPs)were limited by the vertical and horizontal twin *** a result,the pre-nucleation method of two-stage aging increased the proportion of CPs by 34%-38%.Owing to the DPs was effectively suppressed,the alloy's yield strength has been greatly ***,under multi-stage aging,the twin boundaries induce protruding nucleation to form static recrystallization by hindering the migration of dislocations,and the matrix swallows the twins,then the texture gradually tilts from the two poles to the basal *** an important supplement,the grain refinement and oblique texture promoted the improvement of the yield strength of the component.

关键词： Magnesium alloy Pre-deformed Two-stage aging Tensile twinning Continuous precipitates Texture

Piezoelectric film promotes skin wound healing with enhanced collagen deposition and vessels regeneration via upregulation of PI3K/AKT

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Nano Research 2024年第8期17卷 7461-7478页

作者： Qi Xu wufei Dai Peizhe Li Qinglin Li zhen Gao Xiaoli wu Wei Liu Wenbo Wang Department of Plastic and Reconstructive Surgery Shanghai Key Laboratory of Tissue EngineeringShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Research Institute of Plastic Surgery Shandong Second Medical UniversityWeifang 261000China Department of Surgery Air Force Medical CenterPLABeijing 100142China

Skin wounds are common in accidental injuries,and the intricacies of wound repair are closely linked to endogenous electric *** stimulation plays a pivotal role in the restorative processes of skin injuries,encompassing collagen deposition,angiogenesis,inflammation,and *** electrical stimulation therapy replicates and enhances the effects of endogenous wound electric fields by applying an external electric field to the wound site,thereby promoting skin wound *** this study,we developed a self-powered repetitive mechanical impacts-electrical stimulation(RMI-ES)system utilizing a BaTiO_(3)/polydimethylsiloxane(PDMS)piezoelectric composite *** to conventional electrical stimulation devices,the fabricated piezoelectric composite film efficiently harvests energy from the pressure applied by the stimulation device and the tensile force occurring during natural rat *** results demonstrated that piezoelectric stimulation generated by the composite membrane expedited the cell cycle,promoting fibroblast ***,piezoelectric stimulation induced favorable changes in fibroblast gene expression,including increased expression of transforming growth factor-β1(TGF-β1),connective tissue growth factor(CTGF),collagen 1,collagen 3,vascular endothelial growth factor(VEGF),and alpha-smooth muscle actin(α-SMA),while reducing interleukin-6(IL-6)*** analysis revealed that piezoelectric stimulation may induce fibroblast migration,proliferation,and collagen expression by influencing PI3K/AKT serine/threonine kinase(AKT)*** confirmation through the addition of the PI3K inhibitor LY294002 validated that piezoelectric stimulation can regulate the repair process after skin injury through the ***,in vivo results demonstrated that the electric field at the wound site effectively promoted wound healing,reduced inflammation,and stimulated collagen deposition and ne

关键词： BaTiO3/polydimethylsiloxane(PDMS)nano-composite membrane piezoelectrical stimulation skin wound healing collagen deposition PI3K/AKT serine/threonine kinase(AKT)signaling pathway