Ceramic-reinforced metal matrix composites(MMCs)display beneficial properties owing to their combination of ceramic and metal phases.However,the properties are highly dependent on the reinforcing phase composition,vol...Ceramic-reinforced metal matrix composites(MMCs)display beneficial properties owing to their combination of ceramic and metal phases.However,the properties are highly dependent on the reinforcing phase composition,volume fraction and morphology.Continuous fiber or network reinforcement morphologies are difficult and expensive to manufacture,and the often-used discontinuous particle or whisker reinforcement morphologies result in less effective properties.Here,we demonstrate the formation of a co-continuous ceramic-reinforced metal matrix composite using solid-state processing.Binder jet additive manufacturing(BJAM)was used to print a nickel superalloy part followed by post-processing via reactive sintering to form a continuous carbide reinforcing phase at the particle boundaries.The kinetics of reinforcement formation are investigated in order to develop a relationship between reactive sintering time,temperature and powder composition on the reinforcing phase thickness and volume fraction.To evaluate performance,the wear resistance of the reinforced BJAM alloy 625 MMC was compared to unreinforced BJAM alloy 625,demonstrating a 64%decrease in the specific wear rate under abrasive wear conditions.展开更多
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ...In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.展开更多
We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-l...We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-like state withoutapoptosis.The results obtained by the authors highlight the features of theeffects of senescent drift induction in surrounding tissues.In the light of thesefindings,the role of the properties of extracellular matrix and cellular glycocalyxin responses of human tumors to therapy remain uninvestigated.These extracellularbarriers appear to be significant obstacles to effective cancer therapy,especiallyin relation to the use of unique properties of tumor microenvironment forthe immunotherapy-resistant cancer treatment.展开更多
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop...Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.展开更多
The mass of high-speed trains can be reduced using the brake disk prepared with SiC network ceramic frame reinforced 6061 aluminum alloy composite （SiCn/Al）. The thermal and stress analyses of SiCn/Al brake disk dur...The mass of high-speed trains can be reduced using the brake disk prepared with SiC network ceramic frame reinforced 6061 aluminum alloy composite （SiCn/Al）. The thermal and stress analyses of SiCn/Al brake disk during emergency braking at a speed of 300 km/h considering airflow cooling were investigated using finite element （FE） and computational fluid dynamics （CFD） methods. All three modes of heat transfer （conduction, convection and radiation） were analyzed along with the design features of the brake assembly and their interfaces. The results suggested that the higher convection coefficients achieved with airflow cooling will not only reduce the maximum temperature in the braking but also reduce the thermal gradients, since heat will be removed faster from hotter parts of the disk. Airflow cooling should be effective to reduce the risk of hot spot formation and disc thermal distortion. The highest temperature after emergency braking was 461 °C and 359 °C without and with considering airflow cooling, respectively. The equivalent stress could reach 269 MPa and 164 MPa without and with considering airflow cooling, respectively. However, the maximum surface stress may exceed the material yield strength during an emergency braking, which may cause a plastic damage accumulation in a brake disk without cooling. The simulation results are consistent with the experimental results well.展开更多
The dry friction and wear behaviors of co-continuous composites SiC/Fe–40Cr against SiC/Al 2618 alloy were investigated on a ring-on-ring friction and wear tester at sliding speed of 30-105 m/s under the load of 1.0-...The dry friction and wear behaviors of co-continuous composites SiC/Fe–40Cr against SiC/Al 2618 alloy were investigated on a ring-on-ring friction and wear tester at sliding speed of 30-105 m/s under the load of 1.0-2.5 MPa. The experimental result reveals that the characteristic of two body abrasive wear and oxidation wear mechanisms are present for SiCn/2618 Al composite under higher load and sliding speed. SiC ceramic continuous network as the reinforcement can avoid composite from the third body wear that usually occurs in traditional particle reinforced composite. The mechanically mixed layer (MML) controls greatly the wear rate and friction coefficient of the composites. The composites tested at higher sliding speed exhibit higher value of friction coefficient and fluctuation, which is associated with the intermittent formation and removal of the MML. The wear and stress—strain behaviors of SiCn/Fe–40Cr against SiCn/Al 2168 at 30-105 m/s under 1.0-2.5 MPa were analyzed by finite element method with the software Solidwork2012 Simulation, respectively. The wear and stress–strain behavior of the composite predicted by the FEM correlated well with the experimental results.展开更多
Magnesium composites reinforced by N-deficient Ti_(2)AlN MAX phase were first fabricated by non-pressure infiltration of Mg into three-dimensional(3D)co-continuous porous Ti_(2)AlN_(x)(x=0.9,1.0)preforms.The relations...Magnesium composites reinforced by N-deficient Ti_(2)AlN MAX phase were first fabricated by non-pressure infiltration of Mg into three-dimensional(3D)co-continuous porous Ti_(2)AlN_(x)(x=0.9,1.0)preforms.The relationship between their mechanical properties and micro-structure is discussed with the assessment of 2D and 3D characterization.X-ray diffraction(XRD)and scanning electron microscopy detected no impurities.The 3D reconstruction shows that the uniformly distributed pores in Ti_(2)AlN_(x) preforms are interconnected,which act as infiltra-tion tunnels for the melt Mg.The compressive yield strength and microhardness of Ti_(2)AlN_(0.9)/Mg are 353 MPa and 1.12 GPa,respectively,which are 8.55%and 6.67%lower than those of Ti_(2)AlN/Mg,respectively.The typical delamination and kink band occurred in Ti_(2)AlN_(x) under compressive and Vickers hardness(V_(H))tests.Owing to the continuous skeleton structure and strong interfacial bonding strength,the crack ini-tiated in Ti_(2)AlN_(x) was blocked by the plastic Mg matrix.This suggests the possibility of regulating the mechanical performance of Ti_(2)AlN/Mg composites by controlling the N vacancy and the hierarchical structure of Ti_(2)AlN skeleton.展开更多
Ti_(2)AlC/TiAl composites with different volume fractions were prepared by hot pressing technology,and their reinforced structural characteristics and mechanical properties were evaluated.The results showed that when ...Ti_(2)AlC/TiAl composites with different volume fractions were prepared by hot pressing technology,and their reinforced structural characteristics and mechanical properties were evaluated.The results showed that when the reinforced phase volume fraction of Ti_(2)AlC was 20%,three-dimensional interpenetrating network structures were formed in the composites.Above 20%,Ti_(2)AlC phase in the composites accumulated and grew to form thick skeletal networks.The microplastic deformation behavior of Ti_(2)AlC phase,such as kink band and delamination,improved the fracture toughness of the composites.Comparative analysis indicated that the uniform and small interconnecting network structures could further reinforce the composites.The bending strengths of composites prepared with 20 vol.%Ti_(2)AlC reached(900.9±45.0)MPa,which was 25.5% higher than that of TiAl matrix.In general,the co-continuous Ti_(2)AlC/TiAl composite with excellent mechanical properties can be prepared by powder metallurgy method.展开更多
Investigation has been made on the process of synthesizing SiC/Al co-continuous composite by spontaneous melt infiltration. It is found that nitrogen atmosphere is an indispensable factor for spontaneous infiltration ...Investigation has been made on the process of synthesizing SiC/Al co-continuous composite by spontaneous melt infiltration. It is found that nitrogen atmosphere is an indispensable factor for spontaneous infiltration of melt Al into SiC preform with continuous porosity. The critical temperature for spontaneous infiltration occurrence can be lowered and spontaneous infiltration rate increased by doping a small amount of Mg into the Al alloy. Adding fine SiO2 powders into the ceramic preform can play the similar role as Mg-doping by increasing wetting through the chemical reaction of 3SiO2+4AI=2Al2O3+3Si at the infiltration front. Infiltration rate can also be increased by Si-doping to lower the viscosity of the molten Al alloy. In addition, sufficient Si content in the molten Al is also indispensable to avoid the formation of Al4C in the synthesized composite.展开更多
Components of co-continuous phase can form an interpenetrating network structure,which has great potential to synergistically improve the mechanical properties of the blends,and to impart the functional blends superio...Components of co-continuous phase can form an interpenetrating network structure,which has great potential to synergistically improve the mechanical properties of the blends,and to impart the functional blends superior electrical conductivity and permeability.In this work,the effects of shear rates(50-5000 s^(-1))at different temperatures on the phase morphology,phase size and lamellar crystallites of biodegradable co-continuous polybutylene terephthalate(PBAT)/polybutylene succinate(PBS)blend are quantitatively investigated.The results show that the above features of the PBAT/PBS have a strong dependence on the shear flow and thermal field.The co-continuous phase of the blend is well maintained at 130℃.Interestingly,this phase structure transforms into a“sea-island”structure at 160℃,which gradually recovers to a co-continuous phase when the shear rate increases from 1000 s^(-1) to 5000 s^(-1).The phase size decreases with the increase of shear rate both at 130℃ and 160℃ due to the refinement and deformation of phase structures caused by strong shear stress.Unexpectedly,a unique phenomenon is observed that the shear-induced lamellar crystallites are oriented perpendicular to shear direction in the range of 500-5000 s^(-1) at 130℃,while the orientation of lamellar crystallites at 160℃ is along the shear direction within the whole range of shear rates.The degree of orientation for the PBAT/PBS blend crystals increases first and then decreases at both temperatures above.In addition,the range of shear rate has reached the level in the industrial processing.Therefore,this work has important guiding significance for the regulation of the co-continuous phase structure and the performance for the blend in the practical processing.展开更多
The co-continuous(HA+β-TCP)/Zn−3Sn composite was fabricated via vacuum casting-infiltration method.The microstructure,mechanical properties,corrosion behaviors,and hemolysis ratio of the composite were studied by sca...The co-continuous(HA+β-TCP)/Zn−3Sn composite was fabricated via vacuum casting-infiltration method.The microstructure,mechanical properties,corrosion behaviors,and hemolysis ratio of the composite were studied by scanning electron microscope,X-ray diffractometer,mechanical testing,electrochemical test,immersion test,and ultraviolet spectrophotometry.The results indicate that Zn−3Sn alloy infiltrated into porous HA+β-TCP scaffold,which resulted in the formation of a compact(HA+β-TCP)/Zn−3Sn co-continuous composite,without any reaction layer between the Zn−3Sn alloy and the HA+β-TCP scaffold.The compressive strength of the composite was equal to about 3/4 that of Zn−3Sn alloy bulk.The corrosion rate of composite in simulated body fluid solution was slightly higher than that of Zn−3Sn alloy bulk.The main corrosion product on the composite surface was Zn(OH)2.The hemolysis rate of the composite was lower than that of Zn–3Sn alloy bulk and exhibited superior blood compatibility.展开更多
An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distan...An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distance field( VDF). After generating a set of VDF-based features for the given exterior shape and desired internal core structure,a series of simple modifications in distance fields enabled us to obtain an arbitrarily-shaped complex co-continuous composite material computational model. Design results and manufactured prototypes through 3 D printing technology show that the proposed methodology has the potential to open a new paradigm for producing multifunctional next generation co-continuous composite materials which are impossible to design and manufacture using traditional CAD and CAM.展开更多
Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility wit...Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with electrodes.Herein,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport entities.The preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range disorder.Remarkably,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid electrolyte.When used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 mV.The resulting Li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,respectively.Even after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%capacity.Moreover,it displayes stable cycling for over 180 cycles at a high current density of 0.5C.The super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries.展开更多
Intestinal ischemia-reperfusion injury(IIRI)is a complex and severe pathophysiological process characterized by oxidative stress,inflammation,and apoptosis.In recent years,the critical roles of extracellular matrix(EC...Intestinal ischemia-reperfusion injury(IIRI)is a complex and severe pathophysiological process characterized by oxidative stress,inflammation,and apoptosis.In recent years,the critical roles of extracellular matrix(ECM)genes and microRNAs(miRNAs)in IIRI have garnered widespread attention.This review aims to systematically summarize the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI.First,we review the molecular mechanisms of IIRI,focusing on the dual role of the ECM in tissue injury and repair processes.The expression changes and functions of ECM components such as collagen,elastin,and matrix metalloproteinases during IIRI progression are deeply analyzed.Second,we systematically summarize the regulatory roles of miRNAs in IIRI,particularly the mechanisms and functions of miRNAs such as miR-125b and miR-200a in regulating inflammation,apoptosis,and ECM remodeling.Additionally,this review discusses potential diagnostic biomarkers and treatment strategies based on ECM genes and miRNAs.We extensively evaluate the prospects of miRNA-targeted therapy and ECM component modulation in preventing and treating IIRI,emphasizing the clinical translational potential of these emerging therapies.In conclusion,the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI provides new directions for further research,necessitating additional clinical and basic studies to validate and expand these findings for improving clinical outcomes in IIRI patients.展开更多
BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors...BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.AIM To assess the immunohistochemical expression of MMP-9 and MMP-13 in OSCC.METHODS A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective study.The protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive control.All the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical analysis.RESULTS Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor size.The majority of the patients were in advanced TNM stages(III and IV),and showed intense expression of MMP-9 and MMP-13.CONCLUSION The present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and invasiveness.Intense expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with TNM stage.Consequently,it is evident that MMP-9 and MMP-13 are important for the invasiveness and progression of tumors.The findings may facilitate the development of new approaches for evaluating lymph node metastases and interventional therapy techniques,hence enhancing the prognosis of patients diagnosed with OSCC.展开更多
The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functio...The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.展开更多
Increased matrix stiffness of nucleus pulposus(NP)tissue is a main feature of intervertebral disc degeneration(IVDD)and affects various functions of nucleus pulposus cells(NPCs).Glycolysis is the main energy source fo...Increased matrix stiffness of nucleus pulposus(NP)tissue is a main feature of intervertebral disc degeneration(IVDD)and affects various functions of nucleus pulposus cells(NPCs).Glycolysis is the main energy source for NPC survival,but the effects and underlying mechanisms of increased extracellular matrix(ECM)stiffness on NPC glycolysis remain unknown.In this study,hydrogels with different stiffness were established to mimic the mechanical environment of NPCs.Notably,increased matrix stiffness in degenerated NP tissues from IVDD patients was accompanied with impaired glycolysis,and NPCs cultured on rigid substrates exhibited a reduction in glycolysis.展开更多
Quantum dot(QD)-based infrared photodetector is a promising technology that can implement current monitoring,imaging and optical communication in the infrared region. However, the photodetection performance of self-po...Quantum dot(QD)-based infrared photodetector is a promising technology that can implement current monitoring,imaging and optical communication in the infrared region. However, the photodetection performance of self-powered QD devices is still limited by their unfavorable charge carrier dynamics due to their intrinsically discrete charge carrier transport process. Herein, we strategically constructed semiconducting matrix in QD film to achieve efficient charge transfer and extraction.The p-type semiconducting CuSCN was selected as energy-aligned matrix to match the n-type colloidal PbS QDs that was used as proof-of-concept. Note that the PbS QD/CuSCN matrix not only enables efficient charge carrier separation and transfer at nano-interfaces but also provides continuous charge carrier transport pathways that are different from the hoping process in neat QD film, resulting in improved charge mobility and derived collection efficiency. As a result, the target structure delivers high specific detectivity of 4.38 × 10^(12)Jones and responsivity of 782 mA/W at 808 nm, which is superior than that of the PbS QD-only photodetector(4.66 × 10^(11)Jones and 338 mA/W). This work provides a new structure candidate for efficient colloidal QD based optoelectronic devices.展开更多
基金funding support from the Natural Sciences and Engineering Research Council of Canada(NSERC)the Canada Research Chairs(CRC)Program+1 种基金Huys Industries and the CWB Welding Foundationthe Centre for Advanced Materials Joining and the Multi-Scale Additive Manufacturing Lab at the University of Waterloo。
文摘Ceramic-reinforced metal matrix composites(MMCs)display beneficial properties owing to their combination of ceramic and metal phases.However,the properties are highly dependent on the reinforcing phase composition,volume fraction and morphology.Continuous fiber or network reinforcement morphologies are difficult and expensive to manufacture,and the often-used discontinuous particle or whisker reinforcement morphologies result in less effective properties.Here,we demonstrate the formation of a co-continuous ceramic-reinforced metal matrix composite using solid-state processing.Binder jet additive manufacturing(BJAM)was used to print a nickel superalloy part followed by post-processing via reactive sintering to form a continuous carbide reinforcing phase at the particle boundaries.The kinetics of reinforcement formation are investigated in order to develop a relationship between reactive sintering time,temperature and powder composition on the reinforcing phase thickness and volume fraction.To evaluate performance,the wear resistance of the reinforced BJAM alloy 625 MMC was compared to unreinforced BJAM alloy 625,demonstrating a 64%decrease in the specific wear rate under abrasive wear conditions.
基金Supported in part by Natural Science Foundation of Guangxi(2023GXNSFAA026246)in part by the Central Government's Guide to Local Science and Technology Development Fund(GuikeZY23055044)in part by the National Natural Science Foundation of China(62363003)。
文摘In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.
文摘We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-like state withoutapoptosis.The results obtained by the authors highlight the features of theeffects of senescent drift induction in surrounding tissues.In the light of thesefindings,the role of the properties of extracellular matrix and cellular glycocalyxin responses of human tumors to therapy remain uninvestigated.These extracellularbarriers appear to be significant obstacles to effective cancer therapy,especiallyin relation to the use of unique properties of tumor microenvironment forthe immunotherapy-resistant cancer treatment.
基金supported by the Shenzhen Hong Kong Joint Funding Project,No.SGDX20230116093645007(to LY)the Shenzhen Science and Technology Innovation Committee International Cooperation Project,No.GJHZ20200731095608025(to LY)+7 种基金Shenzhen Development and Reform Commission’s Intelligent Diagnosis,Treatment and Prevention of Adolescent Spinal Health Public Service Platform,No.S2002Q84500835(to LY)Shenzhen Medical Research Fund,No.B2303005(to LY)Team-based Medical Science Research Program,No.2024YZZ02(to LY)Zhejiang Provincial Natural Science Foundation of China,No.LWQ20H170001(to RL)Basic Research Project of Shenzhen Science and Technology from Shenzhen Science and Technology Innovation Commission,No.JCYJ20210324103010029(to BY)Shenzhen Second People’s Hospital Clinical Research Fund of Guangdong Province High-level Hospital Construction Project,Nos.2023yjlcyj029(to BY),2023yjlcyj021(to LL)Guangdong Basic and Applied Basic Research Foundation,No.2022A1515110679(to LL)China Postdoctoral Science Foundation,No.2022M722203(to GL).
文摘Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury.
基金Projects (50872018, 50902018) supported by the National Natural Science Foundation of ChinaProject (1099043) supported by the Science and Technology in Guangxi Province, ChinaProject (090302005) supported by the Basic Research Fund for Northeastern University, China
文摘The mass of high-speed trains can be reduced using the brake disk prepared with SiC network ceramic frame reinforced 6061 aluminum alloy composite （SiCn/Al）. The thermal and stress analyses of SiCn/Al brake disk during emergency braking at a speed of 300 km/h considering airflow cooling were investigated using finite element （FE） and computational fluid dynamics （CFD） methods. All three modes of heat transfer （conduction, convection and radiation） were analyzed along with the design features of the brake assembly and their interfaces. The results suggested that the higher convection coefficients achieved with airflow cooling will not only reduce the maximum temperature in the braking but also reduce the thermal gradients, since heat will be removed faster from hotter parts of the disk. Airflow cooling should be effective to reduce the risk of hot spot formation and disc thermal distortion. The highest temperature after emergency braking was 461 °C and 359 °C without and with considering airflow cooling, respectively. The equivalent stress could reach 269 MPa and 164 MPa without and with considering airflow cooling, respectively. However, the maximum surface stress may exceed the material yield strength during an emergency braking, which may cause a plastic damage accumulation in a brake disk without cooling. The simulation results are consistent with the experimental results well.
基金Project (2012BAE06B01) supported by the Key Technology R&D Program During the 12th Five-Year Plan Period, ChinaProjects(21201030, 51272039, 51032007) supported by the National Natural Science Foundation of ChinaProject (1099043) supported by the Science and Technology in Guangxi Province, China
文摘The dry friction and wear behaviors of co-continuous composites SiC/Fe–40Cr against SiC/Al 2618 alloy were investigated on a ring-on-ring friction and wear tester at sliding speed of 30-105 m/s under the load of 1.0-2.5 MPa. The experimental result reveals that the characteristic of two body abrasive wear and oxidation wear mechanisms are present for SiCn/2618 Al composite under higher load and sliding speed. SiC ceramic continuous network as the reinforcement can avoid composite from the third body wear that usually occurs in traditional particle reinforced composite. The mechanically mixed layer (MML) controls greatly the wear rate and friction coefficient of the composites. The composites tested at higher sliding speed exhibit higher value of friction coefficient and fluctuation, which is associated with the intermittent formation and removal of the MML. The wear and stress—strain behaviors of SiCn/Fe–40Cr against SiCn/Al 2168 at 30-105 m/s under 1.0-2.5 MPa were analyzed by finite element method with the software Solidwork2012 Simulation, respectively. The wear and stress–strain behavior of the composite predicted by the FEM correlated well with the experimental results.
基金financially supported by the National Natural Science Foundation of China(No.52175284)the State Key Lab of Advanced Metals and Materials(No.2021-ZD08)the Beijing Government Funds for the Cons tructive Project of Central Universities(No.353139535)。
文摘Magnesium composites reinforced by N-deficient Ti_(2)AlN MAX phase were first fabricated by non-pressure infiltration of Mg into three-dimensional(3D)co-continuous porous Ti_(2)AlN_(x)(x=0.9,1.0)preforms.The relationship between their mechanical properties and micro-structure is discussed with the assessment of 2D and 3D characterization.X-ray diffraction(XRD)and scanning electron microscopy detected no impurities.The 3D reconstruction shows that the uniformly distributed pores in Ti_(2)AlN_(x) preforms are interconnected,which act as infiltra-tion tunnels for the melt Mg.The compressive yield strength and microhardness of Ti_(2)AlN_(0.9)/Mg are 353 MPa and 1.12 GPa,respectively,which are 8.55%and 6.67%lower than those of Ti_(2)AlN/Mg,respectively.The typical delamination and kink band occurred in Ti_(2)AlN_(x) under compressive and Vickers hardness(V_(H))tests.Owing to the continuous skeleton structure and strong interfacial bonding strength,the crack ini-tiated in Ti_(2)AlN_(x) was blocked by the plastic Mg matrix.This suggests the possibility of regulating the mechanical performance of Ti_(2)AlN/Mg composites by controlling the N vacancy and the hierarchical structure of Ti_(2)AlN skeleton.
基金the financial supports from the National Natural Science Foundation of China(No.52065009)the Joint Funds of the Science and Technology Foundation of Guizhou Province,China(No.20157219)the Science and Technology Planning Project of Guizhou Province,China(No.20191069).
文摘Ti_(2)AlC/TiAl composites with different volume fractions were prepared by hot pressing technology,and their reinforced structural characteristics and mechanical properties were evaluated.The results showed that when the reinforced phase volume fraction of Ti_(2)AlC was 20%,three-dimensional interpenetrating network structures were formed in the composites.Above 20%,Ti_(2)AlC phase in the composites accumulated and grew to form thick skeletal networks.The microplastic deformation behavior of Ti_(2)AlC phase,such as kink band and delamination,improved the fracture toughness of the composites.Comparative analysis indicated that the uniform and small interconnecting network structures could further reinforce the composites.The bending strengths of composites prepared with 20 vol.%Ti_(2)AlC reached(900.9±45.0)MPa,which was 25.5% higher than that of TiAl matrix.In general,the co-continuous Ti_(2)AlC/TiAl composite with excellent mechanical properties can be prepared by powder metallurgy method.
基金National Natural Sciellce Foundation of China under grant !No. 59601001
文摘Investigation has been made on the process of synthesizing SiC/Al co-continuous composite by spontaneous melt infiltration. It is found that nitrogen atmosphere is an indispensable factor for spontaneous infiltration of melt Al into SiC preform with continuous porosity. The critical temperature for spontaneous infiltration occurrence can be lowered and spontaneous infiltration rate increased by doping a small amount of Mg into the Al alloy. Adding fine SiO2 powders into the ceramic preform can play the similar role as Mg-doping by increasing wetting through the chemical reaction of 3SiO2+4AI=2Al2O3+3Si at the infiltration front. Infiltration rate can also be increased by Si-doping to lower the viscosity of the molten Al alloy. In addition, sufficient Si content in the molten Al is also indispensable to avoid the formation of Al4C in the synthesized composite.
基金financially supported by the National Key R&D Program of China(No.2018YFB0704200)the National Natural Science Foundation of China(Nos 51822305,52033005,51773135 and 52073185)the Foundation of Science&Technology Department of Sichuan Province(No.21CXRC0105).
文摘Components of co-continuous phase can form an interpenetrating network structure,which has great potential to synergistically improve the mechanical properties of the blends,and to impart the functional blends superior electrical conductivity and permeability.In this work,the effects of shear rates(50-5000 s^(-1))at different temperatures on the phase morphology,phase size and lamellar crystallites of biodegradable co-continuous polybutylene terephthalate(PBAT)/polybutylene succinate(PBS)blend are quantitatively investigated.The results show that the above features of the PBAT/PBS have a strong dependence on the shear flow and thermal field.The co-continuous phase of the blend is well maintained at 130℃.Interestingly,this phase structure transforms into a“sea-island”structure at 160℃,which gradually recovers to a co-continuous phase when the shear rate increases from 1000 s^(-1) to 5000 s^(-1).The phase size decreases with the increase of shear rate both at 130℃ and 160℃ due to the refinement and deformation of phase structures caused by strong shear stress.Unexpectedly,a unique phenomenon is observed that the shear-induced lamellar crystallites are oriented perpendicular to shear direction in the range of 500-5000 s^(-1) at 130℃,while the orientation of lamellar crystallites at 160℃ is along the shear direction within the whole range of shear rates.The degree of orientation for the PBAT/PBS blend crystals increases first and then decreases at both temperatures above.In addition,the range of shear rate has reached the level in the industrial processing.Therefore,this work has important guiding significance for the regulation of the co-continuous phase structure and the performance for the blend in the practical processing.
基金the National Natural Science Foundation of China(No.51101039)the Fundamental Research Funds for the Central Universities,China(No.3072020CFT0702).
文摘The co-continuous(HA+β-TCP)/Zn−3Sn composite was fabricated via vacuum casting-infiltration method.The microstructure,mechanical properties,corrosion behaviors,and hemolysis ratio of the composite were studied by scanning electron microscope,X-ray diffractometer,mechanical testing,electrochemical test,immersion test,and ultraviolet spectrophotometry.The results indicate that Zn−3Sn alloy infiltrated into porous HA+β-TCP scaffold,which resulted in the formation of a compact(HA+β-TCP)/Zn−3Sn co-continuous composite,without any reaction layer between the Zn−3Sn alloy and the HA+β-TCP scaffold.The compressive strength of the composite was equal to about 3/4 that of Zn−3Sn alloy bulk.The corrosion rate of composite in simulated body fluid solution was slightly higher than that of Zn−3Sn alloy bulk.The main corrosion product on the composite surface was Zn(OH)2.The hemolysis rate of the composite was lower than that of Zn–3Sn alloy bulk and exhibited superior blood compatibility.
基金Sponsored by the Scientific Research Foundation of the Higher Education Institutions of Hainan Province of China(Grant No.Hnky2018-101)
文摘An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distance field( VDF). After generating a set of VDF-based features for the given exterior shape and desired internal core structure,a series of simple modifications in distance fields enabled us to obtain an arbitrarily-shaped complex co-continuous composite material computational model. Design results and manufactured prototypes through 3 D printing technology show that the proposed methodology has the potential to open a new paradigm for producing multifunctional next generation co-continuous composite materials which are impossible to design and manufacture using traditional CAD and CAM.
基金supported by the National Natural Science Foundation of China(52003293,51927806,52272258)the Fundamental Research Funds for the Central Universities(2023ZKPYJD07)the Beijing Nova Program(20220484214).
文摘Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for the construction of solid-state lithium batteries due to their excellent flexibility,scalability,and interface compatibility with electrodes.Herein,a novel all-solid polymer electrolyte(PPLCE)was fabricated by the copolymer network of liquid crystalline monomers and poly(ethylene glycol)dimethacrylate(PEGDMA)acts as a structural frame,combined with poly(ethylene glycol)diglycidyl ether short chain interspersed serving as mobile ion transport entities.The preparaed PPLCEs exhibit excellent mechanical property and out-standing electrochemical performances,which is attributed to their unique three-dimensional cocontinuous structure,characterized by a cross-linked semi-interpenetrating network and an ionic liquid phase,resulting in a distinctive nanostructure with short-range order and long-range disorder.Remarkably,the addition of PEGDMA is proved to be critical to the comprehensive performance of the PPLCEs,which effectively modulates the microscopic morphology of polymer networks and improves the mechanical properties as well as cycling stability of the solid electrolyte.When used in a lithiumion symmetrical battery configuration,the 6 wt%-PPLCE exhibites super stability,sustaining operation for over 2000 h at 30 C,with minimal and consistent overpotential of 50 mV.The resulting Li|PPLCE|LFP solid-state battery demonstrates high discharge specific capacities of 160.9 and 120.1 mA h g^(-1)at current densities of 0.2 and 1 C,respectively.Even after more than 300 cycles at a current density of 0.2 C,it retaines an impressive 73.5%capacity.Moreover,it displayes stable cycling for over 180 cycles at a high current density of 0.5C.The super cycle stability may promote the application for ultralong-life all solid-state lithium metal batteries.
基金Supported by Health Science and Technology Programme of Zhejiang Province,No.2022KY1391.
文摘Intestinal ischemia-reperfusion injury(IIRI)is a complex and severe pathophysiological process characterized by oxidative stress,inflammation,and apoptosis.In recent years,the critical roles of extracellular matrix(ECM)genes and microRNAs(miRNAs)in IIRI have garnered widespread attention.This review aims to systematically summarize the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI.First,we review the molecular mechanisms of IIRI,focusing on the dual role of the ECM in tissue injury and repair processes.The expression changes and functions of ECM components such as collagen,elastin,and matrix metalloproteinases during IIRI progression are deeply analyzed.Second,we systematically summarize the regulatory roles of miRNAs in IIRI,particularly the mechanisms and functions of miRNAs such as miR-125b and miR-200a in regulating inflammation,apoptosis,and ECM remodeling.Additionally,this review discusses potential diagnostic biomarkers and treatment strategies based on ECM genes and miRNAs.We extensively evaluate the prospects of miRNA-targeted therapy and ECM component modulation in preventing and treating IIRI,emphasizing the clinical translational potential of these emerging therapies.In conclusion,the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI provides new directions for further research,necessitating additional clinical and basic studies to validate and expand these findings for improving clinical outcomes in IIRI patients.
文摘BACKGROUND One of the main characteristics of oral squamous cell carcinoma(OSCC)is that it metastasizes to cervical lymph nodes frequently with a high degree of local invasiveness.A primary feature of malignant tumors is their penetration of neighboring tissues,such as lymphatic and blood arteries,due to the tumor cells'capacity to break down the extracellular matrix(ECM).Matrix metalloproteinases(MMPs)constitute a family of proteolytic enzymes that facilitate tissue remodeling and the degradation of the ECM.MMP-9 and MMP-13 belong to the group of extracellular matrix degrading enzymes and their expression has been studied in OSCC because of their specific functions.MMP-13,a collagenase family member,is thought to play an essential role in the MMP activation cascade by breaking down the fibrillar collagens,whereas MMP-9 is thought to accelerate the growth of tumors.Elevated MMP-13 expression has been associated with tumor behavior and patient prognosis in a number of malignant cases.AIM To assess the immunohistochemical expression of MMP-9 and MMP-13 in OSCC.METHODS A total of 40 cases with histologically confirmed OSCC by incisional biopsy were included in this cross-sectional retrospective study.The protocols for both MMP-9 and MMP-13 immunohistochemical staining were performed according to the manufacturer’s recommendations along with the normal gingival epithelium as a positive control.All the observations were recorded and Pearson’sχ²test with Fisher exact test was used for statistical analysis.RESULTS Our study showed no significant correlation between MMP-9 and MMP-13 staining intensity and tumor size.The majority of the patients were in advanced TNM stages(III and IV),and showed intense expression of MMP-9 and MMP-13.CONCLUSION The present study suggests that both MMP-9 and MMP-13 play an important and independent role in OSCC progression and invasiveness.Intense expression of MMP-9 and MMP-13,irrespective of histological grade of OSCC,correlates well with TNM stage.Consequently,it is evident that MMP-9 and MMP-13 are important for the invasiveness and progression of tumors.The findings may facilitate the development of new approaches for evaluating lymph node metastases and interventional therapy techniques,hence enhancing the prognosis of patients diagnosed with OSCC.
基金supported by National Institute on Aging(NIH-NIA)R21 AG074152(to KMA)National Institute of Allergy and Infectious Diseases(NIAID)grant DP2 AI171150(to KMA)Department of Defense(DoD)grant AZ210089(to KMA)。
文摘The brain's extracellular matrix(ECM),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECM regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(Miyata et al.,2012),cation buffering(Moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECM indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.
基金supported by the National Nature Science Foundation of China(No.82002345 to J.D and 81902179 to L.S)the Gusu Talent Program(No.Qngg2022008 and GSWS2021027 to J.D)the Preliminary Research Project of the Second Affiliated Hospital of Soochow University(No.SDFEYBS1905 to J.D).
文摘Increased matrix stiffness of nucleus pulposus(NP)tissue is a main feature of intervertebral disc degeneration(IVDD)and affects various functions of nucleus pulposus cells(NPCs).Glycolysis is the main energy source for NPC survival,but the effects and underlying mechanisms of increased extracellular matrix(ECM)stiffness on NPC glycolysis remain unknown.In this study,hydrogels with different stiffness were established to mimic the mechanical environment of NPCs.Notably,increased matrix stiffness in degenerated NP tissues from IVDD patients was accompanied with impaired glycolysis,and NPCs cultured on rigid substrates exhibited a reduction in glycolysis.
基金supported by the National Natural Science Foundation of China (No. 62204079)the Science and Technology Development Project of Henan Province (Nos.202300410048, 202300410057)+2 种基金the China Postdoctoral Science Foundation (No. 2022M711037)the Intelligence Introduction Plan of Henan Province in 2021 (No. CXJD2021008)Henan University Fund。
文摘Quantum dot(QD)-based infrared photodetector is a promising technology that can implement current monitoring,imaging and optical communication in the infrared region. However, the photodetection performance of self-powered QD devices is still limited by their unfavorable charge carrier dynamics due to their intrinsically discrete charge carrier transport process. Herein, we strategically constructed semiconducting matrix in QD film to achieve efficient charge transfer and extraction.The p-type semiconducting CuSCN was selected as energy-aligned matrix to match the n-type colloidal PbS QDs that was used as proof-of-concept. Note that the PbS QD/CuSCN matrix not only enables efficient charge carrier separation and transfer at nano-interfaces but also provides continuous charge carrier transport pathways that are different from the hoping process in neat QD film, resulting in improved charge mobility and derived collection efficiency. As a result, the target structure delivers high specific detectivity of 4.38 × 10^(12)Jones and responsivity of 782 mA/W at 808 nm, which is superior than that of the PbS QD-only photodetector(4.66 × 10^(11)Jones and 338 mA/W). This work provides a new structure candidate for efficient colloidal QD based optoelectronic devices.
