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Research 2023年第4期2023卷 117-130页

作者： Junfei Zhu Gang He Peng-Hang Chen Yajie Zhang Yafei Zhang Shan Lei Yu Zhang Meng Li Peng Huang Jing Lin Marshall Laboratory of biomedical engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)Guangdong Key Laboratory for Biomedical Measurements and Ultrasound ImagingSchool of Biomedical EngineeringShenzhen University Medical SchoolShenzhen 518060China

Heptamethine cyanines(Cy7)are one of the most important dyes in bioimaging and phototherapy,but they often suffer from poor photostability or limited photothermal conversion ***,a facile molecular engineering approach to regulating the photophysical properties of Cy7 by metal ions is *** innovatively modifying the nitrogen with functional groups,a novel terpyridine-grafted nitrogen-terminated Cy7 scaffold(denoted as CydtPy)was synthesized and exhibited tunable photophysical properties when chelating with various metal ions(Mn^(2+),Fe^(2+),etc.).In comparison with metal-ion-free PEGylated CydtPy(LET-11),Mn^(2+)-chelated LET-11(namely,LET-11-Mn)exhibited the increased fluorescence emission intensity,and Fe^(2+)-chelated LET-11(namely,LET-11-Fe)showed the enhanced photostability with~2-fold increase in photothermal conversion *** simply switching the chelated metal ion species,LET-11-Mn or LET-11-Fe could be used for near-infrared fluorescence imaging,magnetic resonance imaging,or photoacoustic ***,LET-11-Fe displayed superior synergistic efficacy of photothermal therapy and chemodynamic therapy both in vitro and in *** work not only provides a new strategy for regulating the photophysical properties of cyanine dyes but also establishes a versatile nanoplatform for cancer theranostics.

关键词： versatile terminated cyanine

Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 311-324页

作者： Qian Yin Fan Wen Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground engineering China University of Mining and TechnologyXuzhou 221116China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China State Key Laboratory for Geomechanics&Deep Underground engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China

The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious ***,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of *** mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically *** results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,***,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the ***σ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite ***ε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse *** increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.

关键词： cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes

Monte Carlo Simulation of Scattered Light with Shear Waves Generated by Acoustic Radiation Force for Acousto-Optic Imaging

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Chinese Physics Letters 2012年第12期29卷 123-126页

作者： LU Ming-Zhu WU Yu-Peng SHI Yu GUAN Yu-Bo GUO Xiao-Li WAN Ming-Xi The Key Laboratory of biomedical Information engineering of Ministry of Education Department of Biomedical EngineeringSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'an 710049

A Monte Carlo method of multiple scattered coherent light with the information of shear wave propagation in scattering media is *** established Monte-Carlo algorithm is mainly relative to optical phase variations due to the acoustic-radiation-force shear-wave-induced displacements of light *** the distributions and temporal behaviors of optical phase increments in probe locations are ***,shear wave speed is evaluated *** is noted that the phase increments exactly track the propagations of shear waves induced by focus-ultrasound radiation *** addition,attenuations of shear waves are demonstrated in simulation *** using linear regression processing,the shear wave speed,which is set to 2.1 m/s in simulation,is estimated to be 2.18 m/s and 2.35 m/s at time sampling intervals of 0.2 ms and 0.5 ms,respectively.

关键词： Shear propagation phase

Recent development in multizonal scaffolds for osteochondral regeneration

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Bioactive Materials 2023年第7期25卷 122-159页

作者： Le Yu Sacha Cavelier Brett Hannon Mei Wei Department of Chemical and Biomolecular engineering Ohio UniversityAthensOH45701USA biomedical engineering program Ohio UniversityAthensOH45701USA Department of Mechanical engineering Ohio UniversityAthensOH45701USA

Osteochondral(OC)repair is an extremely challenging topic due to the complex biphasic structure and poor intrinsic regenerative capability of natural osteochondral *** contrast to the current surgical approaches which yield only short-term relief of symptoms,tissue engineering strategy has been shown more promising outcomes in treating OC defects since its emergence in the *** particular,the use of multizonal scaffolds(MZSs)that mimic the gradient transitions,from cartilage surface to the subchondral bone with either continuous or discontinuous compositions,structures,and properties of natural OC tissue,has been gaining momentum in recent *** the latest developments in the field,this review offers a comprehensive summary of recent advances,current hurdles,and future perspectives of OC repair,particularly the use of MZSs including bilayered,trilayered,multilayered,and gradient scaffolds,by bringing together onerous demands of architecture designs,material selections,manufacturing techniques as well as the choices of growth factors and cells,each of which possesses its unique challenges and opportunities.

关键词： Multizonal scaffolds Osteochondral regeneration Fabrication Cells Growth factors

Propagation of Shear Waves Generated by Acoustic Radiation Force in Nondissipative Inhomogeneous Media

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Chinese Physics Letters 2012年第1期29卷 164-167页

作者： LU Ming-Zhu LIU Xue-Jin SHI Yu KANG Yan-Ni GUAN Yu-Bo WAN Ming-Xi The Key Laboratory of biomedical Information engineering of Ministry of Education Department of Biomedical EngineeringSchool of Life Science and TechnologyXi’an Jiaotong UniversityXi’an 710049

We concentrate on the nondissipative mechanism induced shear wave in inhomogenous *** shear wave equation of radiation force in inhomogeneous media is solved numerically with a finite-difference time-domain method.A rarely studied nondissipative mechanism of shear displacement due to a smooth medium inhomogeneity is *** is noted that unlike the dissipative effect,the nondissipative action on a localized inhomogeneity with its hardness parameter changing smoothly along the beam axis,compresses or stretches the focus *** shear waves in nondissipative inhomogeneous media remain the property of sharp turn with 100% peak positive displacement and 64% peak negative *** action is useful in discerning the water-like lesion.

关键词： method. dissipative inhomogeneous

Composites of sodium manganese oxides with enhanced electrochemical performance for sodium-ion batteries: Tailoring properties via controlling microstructure

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Science China(Technological Sciences) 2016年第7期59卷 1042-1047页

作者： HUANG JiaJia LUO Jian Department of Nano engineering Program of Materials Science and Engineering University of California

Composites of Na_(0.44)Mn O_2, Na_(0.7)Mn O_(2.05), and Na_(0.91) Mn O_2 were synthesized by facile solid-state reaction, ball milling, and annealing methods. Two different composites of identical overall composition but drastically different morphologies and microstructures were synthesized. A composite of a hierarchical porous microstructure with primary and secondary particles(i.e., a "meatball-like" microstructure) achieved an excellent stable capacity of 126 m A h g^(-1) after 100 cycles. The rate capability of the composite could be dramatically enhanced by another round of high-energy ball milling and reannealing; subsequently, a composite that was made up of irregular rods was obtained, for which the capacity was improved by more than 230% to achieve ~53 m A h g^(-1) at a particularly high discharge rate of 50 C. This study demonstrated the feasibility of tailoring the electrochemical performance of electrode materials by simply changing their microstructures via facile ball milling and heat treatments, which can be particularly useful for optimizing composite electrodes for sodium-ion batteries.

关键词： sodium-ion battery cathode material composite electrode microstructure morphology

Structural characterization and strengthening mechanism of forsterite nanostructured scaffolds synthesized by multistep sintering method

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Journal of Materials Science & Technology 2018年第12期34卷 2263-2270页

作者： Fariborz Tavangarian Abbas Fahami Guoqiang Li Mohammadhassan Kazemi Anoosha Forghani Mechanical engineering program School of ScienceEngineering and TechnologyPennsylvania State University Department of Mechanical engineering Texas A&M University Department of Mechanical and industrial engineering Louisiana State University Department of Mechanical and Aerospace engineering University at Buffalo Department of biomedical engineering Millennium Science ComplexPennsylvania State UniversityUniversity Park

In this study, highly porous forsterite scaffolds with interconnected porosities were synthesized using multi-step sintering(MSS) method. The starting powder was nanosized forsterite, which was synthesized from talc and magnesium carbonate powders. The phase composition, average particle size and morphology of the produced forsterite powder were characterized by X-ray diffraction technique(XRD) and transition electron microscopy(TEM). Forsterite scaffolds were produced by foamy method using polymeric sponges. MSS process including three steps was used to efficiently sinter the forsterite nanopowders without destroying the initial porous structure of polymeric sponges. The results showed that MSS technique is an efficient and appropriate procedure to produce highly porous forsterite scaffolds with pore size in the range of 100-300 μm. The compressive strength, compressive modulus and porosity of C12 specimen(sintered at 1650℃ for 1 h with subsequent annealing at 1000℃ for 1000 min) was 1.88 MPa, 29.2 MPa, and 72.4%, respectively, which is very close to that of cancellous bone. The approach studied in this research can be developed for other nanostructure ceramics to produce highly porous scaffolds with interconnected porosities for load bearing applications.

关键词： Forsterite Multi-step sintering Scaffolds Porosity

Confinement-induced nanocrystal alignment of conjugated polymer by the soft-stamped nanoimprint lithography

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Chinese Physics B 2015年第10期24卷 274-280页

作者：李晓慧俞计成陆乃彦张卫东翁雨燕顾臻 Center for Soft Condensed Matter Physics and Interdisciplinary Research & College of Physics Optoelectronics and EnergySoochow University joint Department of biomedical engineering University of North Carolina at Chapel Hill and North Carolina State University

Soft-stamped nanoimprint lithography（NIL） is considered as one of the most effective processes of nanoscale patterning because of its low cost and high throughput. In this work, this method is used to emboss the poly（9, 9-dioctylfluorene）film. By reducing the linewidth of the nanogratings on the stamp, the orientations of nanocrystals are confined along the grating vector in the nanoimprint process, where the confinement linewidth is comparable to the geometrical size of the nanocrystal. When the linewidth is about 400 nm, the poly（9, 9-dioctylfluorene）（PFO） nanocrystals could be orderly arranged in the nanogratings, so that both pattern transfer and well-aligned nanocrystal arrangement could be achieved in a single step by the soft-stamped NIL. The relevant mechanism of the nanocrystalline alignment in these nanogratings is fully discussed. The modulation of nanocrystal alignment is of benefit to the charge mobilities and other performances of PFO-based devices for the future applications.

关键词： conjugated polymer soft lithography nanocrystalline material x-ray technique

An AIEgen/graphene oxide nanocomposite(AIEgen@GO)-based two-stage“turn-on”nucleic acid biosensor for rapid detection of SARS-CoV-2 viral sequence

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Aggregate 2023年第1期4卷 219-230页

作者： Qin Zhang Bohan Yin Jianhua Hao Linjie Ma Yingying Huang Xueying Shao Chuanqi Li Zhiqin Chu Changqing Yi Siu Hong Dexter Wong Mo Yang Department of biomedical engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongChina Department of Electrical and Electronic engineering Joint Appointment with School of Biomedical SciencesThe University of Hong KongHong KongChina Key Laboratory of Sensing Technology and biomedical Instruments(Guangdong Province) School of Biomedical EngineeringSun Yat-Sen UniversityGuangzhouPR China

The ongoing outbreak of Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)pandemic has posed significant challenges in early viral ***,it is urgently desirable to develop a rapid,inexpensive,and sensitive method to aid point-of-care SARS-CoV-2 *** this work,we report a highly sequence-specific biosensor based on nanocomposites with aggregationinduced emission luminogens(AIEgen)-labeled oligonucleotide probes on graphene oxide nanosheets(AIEgen@GO)for one step-detection of SARS-CoV-2-specific nucleic acid sequences(Orf1ab or N genes).A dual“turn-on”mechanism based on AIEgen@GO was established for viral nucleic acids ***,the first-stage fluorescence recovery was due to dissociation of the AIEgen from GO surface in the presence of target viral nucleic acid,and the second-stage enhancement of AIEbased fluorescent signal was due to the formation of a nucleic acid duplex to restrict the intramolecular rotation of the ***,the feasibility of our platform for diagnostic application was demonstrated by detecting SARS-CoV-2 virus plasmids containing both Orf1ab and N genes with rapid detection around 1 h and good sensitivity at pM level without *** platform shows great promise in assisting the initial rapid detection of the SARS-CoV-2 nucleic acid sequence before utilizing quantitative reverse transcription-polymerase chain reaction for second confirmation.

关键词： aggregation-induced emission(AIE)luminogen graphene oxide SARS-CoV-2 detection

Amyotrophic lateral sclerosis as a synaptopathy

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Neural Regeneration Research 2019年第2期14卷 189-192页

作者： Matthew J.Fogarty Department of Physiology and biomedical engineering Mayo Clinic School of biomedical Sciences The University of Queensland

The synapse is an incredibly specialized structure that allows for the coordinated communication of information from one neuron to another. When assembled into circuits, steady streams of excitatory and inhibitory synaptic activity shape neural outputs. At the organismal level, ensembles of neural networks underlie behavior, emotion and memory. Disorder or dysfunctions of synapses, a synaptopathy, may underlie a host of developmental and degenerative neurological conditions. There is a possibility that amyotrophic lateral sclerosis may be a result of a synaptopathy within the neuromotor system. To this end, particular attention has been trained on the excitatory glutamatergic synapses and their morphological proxy, the dendritic spine. The extensive detailing of these dysfunctions in vulnerable neuronal populations, including corticospinal neurons and motor neurons, has recently been the subject of original research in rodents and humans. If amyotrophic lateral sclerosis is indeed a synaptopathy, it is entirely consistent with other proposed pathogenic mechanisms – including glutamate excitotoxicity, accumulation of misfolded proteins and mitochondrial dysfunction at distal axon terminals(cortico-motor neuron and neuromuscular). Further, although the exact mechanism of disease spread from region to region is unknown, the synaptopathy hypothesis is consistent with emerging die-forward evidence and the prion-like propagation of misfolded protein aggregates to distant neuronal populations. Here in this mini-review, we focus on the timeline of synaptic observations in both cortical and spinal neurons from different rodent models, and provide a conceptual framework for assessing the synaptopathy hypothesis in amyotrophic lateral sclerosis.

关键词： motor neuron motor cortex corticospinal excitotoxicity synaptic transmission dendrites dendriticspines neuromuscular junction