The incidence of new-onset cardiac conduction disturbances following transcatheter aortic valve implantation(TAVI)has not decreased compared to other complications,and nowadays is by far the most frequent drawback fol...The incidence of new-onset cardiac conduction disturbances following transcatheter aortic valve implantation(TAVI)has not decreased compared to other complications,and nowadays is by far the most frequent drawback following the procedure.Meanwhile,the global management of TAVI recipients has led to a minimalist approach with short postprocedural length of stay,which may be limited by the occurrence of late arrhythmic events in patients at high-risk.This review focuses on those strategies to overcome the conundrum between early discharge and new-onset conduction disturbances in elderly TAVI candidates and provides a perspective on future improvements in this field.展开更多
Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG...Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG wide LBBB-pattern QRS duration and clinical assessment, imaging studies. Conduction system pacing (CSP), such as His bundle pacing (HBP)and left bundle branch pacing (LBBP), may help to prevent PICM,^([2]) but the criteria for optimal patient selection remain inadequately defined.展开更多
Gels and conductive polymer composites,including hydrogen bonds(HBs),have emerged as promising materials for electro-magnetic wave(EMW)absorption across various applications.However,the relationship between conduction...Gels and conductive polymer composites,including hydrogen bonds(HBs),have emerged as promising materials for electro-magnetic wave(EMW)absorption across various applications.However,the relationship between conduction loss in EMW-absorbing materials and charge transfer in HB remains to be fully understood.In this study,we developed a series of deep eutectic gels to fine-tune the quantity of HB by adjusting the molar ratio of choline chloride(ChCl)and ethylene glycol(EG).Owing to the unique properties of deep eutectic gels,the effects of magnetic loss and polarization loss on EMW attenuation can be disregarded.Our results indicate that the quantity of HB initially increases and then decreases with the introduction of EG,with HB-induced conductive loss following similar pat-terns.At a ChCl and EG molar ratio of 2.4,the gel labeled G22-CE2.4 exhibited the best EMW absorption performance,characterized by an effective absorption bandwidth of 8.50 GHz and a thickness of 2.54 mm.This superior performance is attributed to the synergistic ef-fects of excellent conductive loss and impedance matching generated by the optimal number of HB.This work elucidates the role of HB in dielectric loss for the first time and provides valuable insights into the optimal design of supramolecular polymer absorbers.展开更多
Objective:Arrhythmia-induced cardiomyopathy(AIC)is a reversible dilated cardiomyopathy induced by rapid or irregular heartbeat.Acupuncture has a long history of use in the treatment of cardiac diseases,and Xinshu(BL15...Objective:Arrhythmia-induced cardiomyopathy(AIC)is a reversible dilated cardiomyopathy induced by rapid or irregular heartbeat.Acupuncture has a long history of use in the treatment of cardiac diseases,and Xinshu(BL15)is a key acupoint.However,the underlying mechanism of acupuncture at BL15 in the treatment of AIC has not yet been elucidated.Methods:AIC was induced in adult male Sprague-Dawley(SD)rats by continuous administration of acetylcholine(ACh)-CaCl2 and treatment with electroacupuncture(EA)at bilateral BL15.Echocardiography was used to evaluate cardiac function;the rotarod test for motor coordination and performance;hematoxylin and eosin(HE)staining for the morphology of ventricles;electrocardiogram for susceptibility,inducibility,and duration of atrial fibrillation(AF);and electrical and optical mapping in isolated rat hearts maintained by the Langendorff perfusion system for electrical conduction and intracellular handling,respectively.Reverse transcription quantitative polymerase chain reaction(RT-qPCR)and Western blotting were used to determine the levels of cardiac conduction and intracellular calcium-handling proteins in the ventricle.Results:The results showed that EA improved the ejection factor and morphological indices on echocardiography,restored motor coordination and performance,and alleviated ventricular dilation and AF onset.EA alleviates atrial conduction disorders,shortens APD80,and decreases calcium handling in rats with AIC.Cx43 was downregulated and CaMKII was upregulated,and both effects were reversed by EA treatment.Conclusion:Our study provides a novel AIC model with abnormal electrical propagation and calcium handling that can be protected by EA at BL15.This potential mechanism may be associated with the modulation of Cx43 and CaMKII expression.展开更多
Exploring a new and robust material for proton conduction is of significant importance to the scientific interest and technological importance.Polyoxometalates(POMs)are a class of molecular anion metal oxide clusters ...Exploring a new and robust material for proton conduction is of significant importance to the scientific interest and technological importance.Polyoxometalates(POMs)are a class of molecular anion metal oxide clusters with well-defined structures and diverse properties.Therefore,the design and synthesis of a POM-based material for proton conduction is extremely vital.Herein,a dimeric four tartaric acid-bridged tetra-Zr-incorporated arsenotungstate.展开更多
After millions of years of natural evolution,horsetails have evolved unique stem structures that enable survival in harsh environments.Inspired by the cross-sectional characteristics of horsetail stems,a series of bio...After millions of years of natural evolution,horsetails have evolved unique stem structures that enable survival in harsh environments.Inspired by the cross-sectional characteristics of horsetail stems,a series of bioinspired sandwich structures were designed and fabricated using the laser powder bed fusion(LPBF)process.By combining experimental and finite element simulation methods,the formability,mechanical properties,deformation behavior,and thermal conduction performance of these structures were determined.Results show that the surface morphology of the bioinspired sandwich structures was smooth,with no cracks observed.The bioinspired sandwich structure with an inner tube diameter of 1.9 mm(D_(1.9))exhibited optimal comprehensive mechanical properties,with a specific strength of 64.2 MPa/(g/cm^(3)),and specific energy absorption of 3.3 J/g.Stress distribution results revealed that the D_(1.9)structures had the most uniform stress distribution.Furthermore,increasing the internal conduction paths improved heat transfer;therefore,the thermal conductivities of the D_(1.4),D_(1.9),and D_(2.4)structures were higher than that of the D0 structure.This study demonstrates that a bioinspired design approach,combined with additive manufacturing technology,enables the development of high-performance structures with both load-bearing and thermally insulating capabilities.展开更多
Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)is considered to be the most potential light-absorbing material to replace CuInGaSe_(2)(CIGS),but the actual photoelectric conversion efficiency of such cells is much lower than that of CIG...Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)is considered to be the most potential light-absorbing material to replace CuInGaSe_(2)(CIGS),but the actual photoelectric conversion efficiency of such cells is much lower than that of CIGS.One of the reasons is the high recombination rate of carriers at the interface.In this paper,in order to reduce the carrier recombination,a new solar cell structure with double absorber layers of Al-doped ZnO(AZO)/intrinsic(i)-ZnO/CdS/CZTS_(x1)Se_(1−x1)(CZTSSe_(1))/CZTS_(x2)Se_(1−x2)(CZTSSe_(2))/Mo was proposed,and the optimal conduction band offsets(CBOs)of CdS/CZTSSe_(1) interface and CZTSSe_(1)/CZTSSe_(2) interface were determined by changing the S ratio in CZTSSe_(1) and CZTSSe_(2),and the effect of thickness of CZTSSe_(1) on the performance of the cell was studied.The efficiencies of the optimized single and double absorber layers reached 17.97%and 23.4%,respectively.Compared with the single absorber layer structure,the proposed structure with double absorber layers has better cell performance.展开更多
The development of high-performance functional composites has become a research hotspot in response to the hazards of over-heating and electromagnetic radiation in modern electronic devices.Herein,we grew magnetic Fe_...The development of high-performance functional composites has become a research hotspot in response to the hazards of over-heating and electromagnetic radiation in modern electronic devices.Herein,we grew magnetic Fe_(3)O_(4)particles in situ on the MXene layer to obtain an MXene@Fe_(3)O_(4)composite with rich heterogeneous interfaces.Owing to the unique heterostructure and the synergistic effects of multiple electromagnetic wave absorption mechanisms,the composite achieved a minimum reflection loss of-27.14 dB and an effect-ive absorption bandwidth of 2.05 GHz at an absorption thickness of 2 mm.Moreover,the MXene@Fe_(3)O_(4)composite could be encapsu-lated in thermoplastic polyurethane(TPU)via thermal curing.The obtained composite elastomer exhibited a strong tensile strength,and its thermal diffusivity was 113%higher than that of pure TPU.Such additional mechanical properties and thermal conduction features render this composite elastomer an advanced electromagnetic absorber to adapt to the ever-changing environment for expanding practical applications.展开更多
We present a minimal theoretical model for self-sustained oscillations of a thin elastic sheet on a hot plate,induced by thermomechanical coupling.As the plate temperature increases,the sheet’s static deflection beco...We present a minimal theoretical model for self-sustained oscillations of a thin elastic sheet on a hot plate,induced by thermomechanical coupling.As the plate temperature increases,the sheet’s static deflection becomes unstable via a Hopf bifurcation at a critical temperature TC,giving rise to spontaneous periodic motion.Linear stability analysis yields analytical expressions for the critical oscillation temperature TC and the oscillation period at onset.Numerical simulations of the nonlinear equations confirm the bifurcation and reveal how key parameters(stiffness,thermal softening,thermal coupling,etc.)govern the oscillation amplitude and waveform.Finally,we demonstrate that the self-oscillating sheet can perform mechanical work as a heat engine,and we compare its performance to the Carnot efficiency limit.This work provides design principles for thermally driven selfoscillators with potential applications in soft robotics,adaptive structures,and thermal energy harvesting.展开更多
The absence of efficient ion transport pathways in composite solid-state electrolytes(CSEs)usually results in low ionic conductivity,which remains a great challenge for developing solid-state lithiummetal batteries(SL...The absence of efficient ion transport pathways in composite solid-state electrolytes(CSEs)usually results in low ionic conductivity,which remains a great challenge for developing solid-state lithiummetal batteries(SLMBs).Herein,we report achieving accelerated Li^(+)conduction in CSEs by a novel activation of the interfacial dipole layer.Polycationic ionic liquids and polyacrylonitrile with highly polar functional groups(-C≡N)are utilized to modulate the interfacial dipole layer in MOF-based CSEs,facilitating long-range pathways for the connectivity of Li^(+)conduction and enhancing rapid transport kinetics.The as-synthesized CSEs exhibit a high ionic conductivity of 0.59 mS cm^(-1)and a lithium transfer number of 0.85.The assembled SLMBs(Li/CSE/LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))delivered a high-capacity retention of 88.7%with a minimal discharge voltage attenuation of 17.1 mV after 500 cycles(0.03 mV per cycle)at0.5 C.This work offers an effective approach to creating interpenetrating lithium-ion transport pathways with rapid ion transport kinetics for solid-state electrolytes,thereby advancing the development of solidstate lithium metal batteries.展开更多
With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavi...With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavior of materials in ultrashort time scales.Theoretically,generalized heat conductive models are considered in this work.By analogy with mechanical viscoelastic models,this paper further enriches the heat conduction models and gives their one-dimensional physical expression.Numerically,the transient thermoelastic response of the slim strip material under thermal shock is investigated by applying the proposed models.First,the analytical solution in the Laplace domain is obtained by the Laplace transform.Then,the numerical results of the transient responses are obtained by the numerical inverse Laplace transform.Finally,the transient responses of different models are analyzed and compared,and the effects of material parameters are discussed.This work not only opens up new research perspectives on generalized heat conductive and thermoelastic coupling theories,but also is expected to be beneficial for the deeper understanding of the heat wave theory.展开更多
A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses the...A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves conductivity.mPR-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain dispersion.Integrating this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 cycles.In situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen reactions.Ex situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability tests.The present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.展开更多
To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D...To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D frameworks,designated as[La(HPO_(3))(C_(2)O_(4))0.5(H_(2)O)_(2)](La‑1)and(C_(6)H_(16)N_(2))(H_(3)O)[La_(2)(H_(2)PO_(3))_(3)(C_(2)O_(4))_(3)(H_(2)O)](La‑2)(C_(6)H_(14)N_(2)=cis-2,6-dimethylpiperazine),were prepared by hydrothermal and solvothermal conduction,respectively.La‑1 was constructed with lanthanum phosphite 2D layers and C_(2)O_(4)^(2-)groups,whereas La‑2 was constructed with lanthanum oxalate 2D layers and H_(2)PO^(3-)groups.Alternating current(AC)impedance spectra indicate that the pro-ton conductivities of both compounds could reach 10^(-4)S·cm^(-1)and remain highly durable at 75℃and 98%of rela-tive humidity(RH).Due to the abundance of H-bonds in La‑2,theσof La‑2 was higher than that of La‑1.La‑1 exhibited excellent water and pH stability.CCDC:2439965,La‑1;443776,La‑2.展开更多
This paper examined how microstructure influences the homogenized thermal conductivity of cellular structures and revealed a surface-induced size-dependent effect.This effect is linked to the porous microstructural fe...This paper examined how microstructure influences the homogenized thermal conductivity of cellular structures and revealed a surface-induced size-dependent effect.This effect is linked to the porous microstructural features of cellular structures,which stems from the degree of porosity and the distri-bution of the pores.Unlike the phonon-driven surface effect at the nanoscale,the macro-scale surface mechanism in thermal cellular structures is found to be the microstructure-induced changes in the heat conduction path based on fully resolved 3D numerical simulations.The surface region is determined by the microstructure,characterized by the intrinsic length.With the coupling between extrinsic and intrinsic length scales under the surface mechanism,a surface-enriched multiscale method was devel-oped to accurately capture the complex size-dependent thermal conductivity.The principle of scale separation required by classical multiscale methods is not necessary to be satisfied by the proposed multiscale method.The significant potential of the surface-enriched multiscale method was demon-strated through simulations of the effective thermal conductivity of a thin-walled metamaterial struc-ture.The surface-enriched multiscale method offers higher accuracy compared with the classical multiscale method and superior efficiency over high-fidelity finite element methods.展开更多
The water conductivity of karst collapsed column is affected by multiple factors such as the characteristics of its own column filling,structure and mining disturbance.As a structural water-conducting channel,fault us...The water conductivity of karst collapsed column is affected by multiple factors such as the characteristics of its own column filling,structure and mining disturbance.As a structural water-conducting channel,fault usually plays a controlling role in hydrogeological structure.During the process of mine water hazard prevention and control,it was discovered that the lithology composition,compaction and cementation degree and water physical properties of karst collapsed column fillings were all non-conducting water,but due to the influence of combined development faults,some exploration drill holes showed concentrated water outflow.Based on this,the scientific hypothesis was proposed that fault cutting leads to water conduction in karst collapsed columns.The study comprehensively used methods like chronology,exploration data analysis,and hydrochemical testing to analyze the chronological relationship between faults and karst collapsed columns,their spatial relationship,outlet point distribution and water chemical properties,and the impact of faults on the water-conductivity of karst collapsed columns,which proved the effect of fault cutting on changing water conductivity of karst collapsed column.The research showed that later fault cutting through karst collapsed columns turned the originally non-conductive karst collapsed columns into water-conductive collapsed columns at the fault plane,creating a longitudinally connected water-conducting channel.A new model of fault cutting karst collapsed column to change the original water conductivity of karst collapsed column was proposed.The research results can provide a theoretical basis for the prediction of the water conductivity of the karst collapsed column.According to whether the karst collapsed column was cut by the fault,it was predicted theoretically,so as to determine the key areas of water conductivity detection and prevention and control,and has broad application prospects under the background of source control of mine water disaster.展开更多
Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic co...Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic conductivity and interfacial stability remains a challenge.Here,a donor-acceptor(D-A)like solid plasticizer,tris(pentafluorophenyl)borane(TPFPB),containing electron-rich F atoms and electrondeficient B sites,was introduced to regulate the ion transport behavior and interfacial chemistry of polyethylene oxide(PEO)-based SPEs.Owing to the multiple ion-dipole interactions(F Li^(+)TFSI^(-)and B TFSI^(-)Li^(+))between the TPFPB molecule and Li salts,a multimodal electrolyte environment featuring more free Li^(+)and trapped TFSI^(-)anions was generated,which cooperates with the reduced crystallinity of PEO,significantly facilitating the rapid migration of Li^(+).More importantly,TPFPB tends to be preferentially reduced to form a stable inorganic-rich solid electrolyte interphase on the Li-metal anode,ensuring uniform Li plating/stripping behavior.Thus,the TPFPB-modulated SPEs system achieves a high Li^(+)conductivity of 0.74 m S cm^(-1)and effectively suppresses dendrite growth,which enables a long-cycle dendrite-free Li/Li symmetric cell for over 5000 h,and remarkable electrochemical performance has been further validated in operational ASSLMBs.The findings in this work would inspire efforts to develop highperformance SPEs for all-solid-state alkali-metal batteries.展开更多
Highly reduced molybdenum red(MR)clusters have emerged as a new type of polyoxomolybdates(POMos)and showed great potential as electron/proton reservoirs for energy conversion and storage,as well as for catalysis.Howev...Highly reduced molybdenum red(MR)clusters have emerged as a new type of polyoxomolybdates(POMos)and showed great potential as electron/proton reservoirs for energy conversion and storage,as well as for catalysis.However,the limited structural diversity of MR clusters significantly hinders further exploration of their potential as functional materials.Herein,we describe the synthesis of a novel highly reduced MR cluster{Mo_(49)}(compound 1)based on rational assembly of a variety of basic building blocks(BBs).In addition to the well-established BBs found in the family of MR clusters,the unique tetrahedral{MoVI 4}BB plays a key role in directing the assembly to afford trigonal pyramid-like structure of compound 1,which consists of 49 Mo and 148 O atoms with a high reduction degree of 73%.Moreover,at 80℃and 98%relative humidity(RH),the pellet sample of compound 1 displays good proton conductivity of 7.88×10^(-3)S/cm owing to the efficient hydrogen-bonded network built from the surface oxygen atoms,protons and vip water molecules.This research offers new insights into the assembly and synthesis of MR clusters through a BB strategy and manifests their significant potential for advanced applications.展开更多
The paper proposes an approximate solution to the classical (parabolic) multidimensional 2D and 3D heat conduction equation for a 5 × 5 cm aluminium plate and a 5 × 5 × 5 cm aluminum cube. An approximat...The paper proposes an approximate solution to the classical (parabolic) multidimensional 2D and 3D heat conduction equation for a 5 × 5 cm aluminium plate and a 5 × 5 × 5 cm aluminum cube. An approximate solution of the generalized (hyperbolic) 2D and 3D equation for the considered plate and cube is also proposed. Approximate solutions were obtained by applying calculus of variations and Euler-Lagrange equations. In order to verify the correctness of the proposed approximate solutions, they were compared with the exact solutions of parabolic and hyperbolic equations. The paper also presents the research on the influence of time parameters τ as well as the relaxation times τ ∗ to the variation of the profile of the temperature field for the considered aluminum plate and cube.展开更多
Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. ...Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.展开更多
The development of core-shell nanoclusters with controllable composition is of utmost importance as the material properties depend on their constituent elements.However,precisely tuning their compositions at the atomi...The development of core-shell nanoclusters with controllable composition is of utmost importance as the material properties depend on their constituent elements.However,precisely tuning their compositions at the atomic scale is not easily achieved because of the difficulty of using limited macroscopic synthetic methods for atomic-level modulation.In this work,we report an interesting example of precisely regulating the core composition of an inorganic core-shell-type cobalt polyoxoniobate[Co_(26)Nb_(36)O_(140)]^(32−)by controlling reaction conditions,in which the inner Co-core composition could be tune while retaining the outer Nb-shell composition of resulting product,leading to a series of isostructural species with a general formula of{Co_(26-n)Nb_(36+n)O_(140)}(n=0–2).These rare species not only can display good powder and single-crystal proton conductivities,but also might provide helpful and atomic-level insights into the syntheses,structures and composition modifications of inorganic amorphous core-shell heterometal oxide nanoparticles.展开更多
文摘The incidence of new-onset cardiac conduction disturbances following transcatheter aortic valve implantation(TAVI)has not decreased compared to other complications,and nowadays is by far the most frequent drawback following the procedure.Meanwhile,the global management of TAVI recipients has led to a minimalist approach with short postprocedural length of stay,which may be limited by the occurrence of late arrhythmic events in patients at high-risk.This review focuses on those strategies to overcome the conundrum between early discharge and new-onset conduction disturbances in elderly TAVI candidates and provides a perspective on future improvements in this field.
文摘Pacing-induced cardiomyopathy (PICM) resultsf rom the detrimental effect of frequent right ventricular pacing.^([1]) The diagnosis relies on a combination of pacing-associated ventricular dyschrony manifested with ECG wide LBBB-pattern QRS duration and clinical assessment, imaging studies. Conduction system pacing (CSP), such as His bundle pacing (HBP)and left bundle branch pacing (LBBP), may help to prevent PICM,^([2]) but the criteria for optimal patient selection remain inadequately defined.
基金supported by the National Nat-ural Science Foundation of China(Nos.51872238,52074227,and 21806129)the Fundamental Research Funds for the Central Universities,China(Nos.3102018zy045 and 3102019AX11)+2 种基金the Guangdong Basic and Applied Basic Research Foundation,China(No.2024A1515010298)the Natural Science Basic Research Plan in Shaanxi Province of China(Nos.2017JQ5116 and 2020JM-118)the Key Laboratory of Icing and Anti/De-icing of CARDC(No.IADL20220401).
文摘Gels and conductive polymer composites,including hydrogen bonds(HBs),have emerged as promising materials for electro-magnetic wave(EMW)absorption across various applications.However,the relationship between conduction loss in EMW-absorbing materials and charge transfer in HB remains to be fully understood.In this study,we developed a series of deep eutectic gels to fine-tune the quantity of HB by adjusting the molar ratio of choline chloride(ChCl)and ethylene glycol(EG).Owing to the unique properties of deep eutectic gels,the effects of magnetic loss and polarization loss on EMW attenuation can be disregarded.Our results indicate that the quantity of HB initially increases and then decreases with the introduction of EG,with HB-induced conductive loss following similar pat-terns.At a ChCl and EG molar ratio of 2.4,the gel labeled G22-CE2.4 exhibited the best EMW absorption performance,characterized by an effective absorption bandwidth of 8.50 GHz and a thickness of 2.54 mm.This superior performance is attributed to the synergistic ef-fects of excellent conductive loss and impedance matching generated by the optimal number of HB.This work elucidates the role of HB in dielectric loss for the first time and provides valuable insights into the optimal design of supramolecular polymer absorbers.
基金supported by the National Key R&D Program of China(2022YFC3500405,2019YFC1712105)The National Science Foundation of China(82374075)+1 种基金The National Comprehensive Traditional Chinese Medicine Reform Demonstration Zone Science and Technology Collaborative Development Project(GZY-KJS-SD-2024-046)Taishan Scholar Youth Project of Shandong Province(tsqn202306188).
文摘Objective:Arrhythmia-induced cardiomyopathy(AIC)is a reversible dilated cardiomyopathy induced by rapid or irregular heartbeat.Acupuncture has a long history of use in the treatment of cardiac diseases,and Xinshu(BL15)is a key acupoint.However,the underlying mechanism of acupuncture at BL15 in the treatment of AIC has not yet been elucidated.Methods:AIC was induced in adult male Sprague-Dawley(SD)rats by continuous administration of acetylcholine(ACh)-CaCl2 and treatment with electroacupuncture(EA)at bilateral BL15.Echocardiography was used to evaluate cardiac function;the rotarod test for motor coordination and performance;hematoxylin and eosin(HE)staining for the morphology of ventricles;electrocardiogram for susceptibility,inducibility,and duration of atrial fibrillation(AF);and electrical and optical mapping in isolated rat hearts maintained by the Langendorff perfusion system for electrical conduction and intracellular handling,respectively.Reverse transcription quantitative polymerase chain reaction(RT-qPCR)and Western blotting were used to determine the levels of cardiac conduction and intracellular calcium-handling proteins in the ventricle.Results:The results showed that EA improved the ejection factor and morphological indices on echocardiography,restored motor coordination and performance,and alleviated ventricular dilation and AF onset.EA alleviates atrial conduction disorders,shortens APD80,and decreases calcium handling in rats with AIC.Cx43 was downregulated and CaMKII was upregulated,and both effects were reversed by EA treatment.Conclusion:Our study provides a novel AIC model with abnormal electrical propagation and calcium handling that can be protected by EA at BL15.This potential mechanism may be associated with the modulation of Cx43 and CaMKII expression.
基金supported by the National Natural Science Foundation of China(Nos.22071043 and 22203027)Shanxi Province Science Foundation(No.202303021211194)the program for the(Reserved)Discipline Leaders of Taiyuan Institute of Technology.
文摘Exploring a new and robust material for proton conduction is of significant importance to the scientific interest and technological importance.Polyoxometalates(POMs)are a class of molecular anion metal oxide clusters with well-defined structures and diverse properties.Therefore,the design and synthesis of a POM-based material for proton conduction is extremely vital.Herein,a dimeric four tartaric acid-bridged tetra-Zr-incorporated arsenotungstate.
基金supported by National Key Research and Development Program of China(Grant No.2021YFB1715400)National Natural Science Foundation of China(Grant No.52225503)+3 种基金Key Research and Development Program of Jiangsu Province(Grant Nos.BE2022069,BE2022069-1)Fundamental Research Funds for the Central Universities(Grant No.NI2024003)National Natural Science Foundation of China for Creative Research Groups(Grant No.51921003)the 15th Batch of“Six Talents Peaks”Innovative Talents Team Program(Grant No.TD-GDZB-001).
文摘After millions of years of natural evolution,horsetails have evolved unique stem structures that enable survival in harsh environments.Inspired by the cross-sectional characteristics of horsetail stems,a series of bioinspired sandwich structures were designed and fabricated using the laser powder bed fusion(LPBF)process.By combining experimental and finite element simulation methods,the formability,mechanical properties,deformation behavior,and thermal conduction performance of these structures were determined.Results show that the surface morphology of the bioinspired sandwich structures was smooth,with no cracks observed.The bioinspired sandwich structure with an inner tube diameter of 1.9 mm(D_(1.9))exhibited optimal comprehensive mechanical properties,with a specific strength of 64.2 MPa/(g/cm^(3)),and specific energy absorption of 3.3 J/g.Stress distribution results revealed that the D_(1.9)structures had the most uniform stress distribution.Furthermore,increasing the internal conduction paths improved heat transfer;therefore,the thermal conductivities of the D_(1.4),D_(1.9),and D_(2.4)structures were higher than that of the D0 structure.This study demonstrates that a bioinspired design approach,combined with additive manufacturing technology,enables the development of high-performance structures with both load-bearing and thermally insulating capabilities.
基金supported by the Science and Technology Innovation Development Program(No.70304901).
文摘Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)is considered to be the most potential light-absorbing material to replace CuInGaSe_(2)(CIGS),but the actual photoelectric conversion efficiency of such cells is much lower than that of CIGS.One of the reasons is the high recombination rate of carriers at the interface.In this paper,in order to reduce the carrier recombination,a new solar cell structure with double absorber layers of Al-doped ZnO(AZO)/intrinsic(i)-ZnO/CdS/CZTS_(x1)Se_(1−x1)(CZTSSe_(1))/CZTS_(x2)Se_(1−x2)(CZTSSe_(2))/Mo was proposed,and the optimal conduction band offsets(CBOs)of CdS/CZTSSe_(1) interface and CZTSSe_(1)/CZTSSe_(2) interface were determined by changing the S ratio in CZTSSe_(1) and CZTSSe_(2),and the effect of thickness of CZTSSe_(1) on the performance of the cell was studied.The efficiencies of the optimized single and double absorber layers reached 17.97%and 23.4%,respectively.Compared with the single absorber layer structure,the proposed structure with double absorber layers has better cell performance.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LQ22E030016)the National Natural Science Foundation of China(No.52275137)+1 种基金the China Postdoctoral Science Foundation(No.2022M722831)the Postdoctoral Research Selected Funding Project of Zhejiang Province,China(No.ZJ2022063).
文摘The development of high-performance functional composites has become a research hotspot in response to the hazards of over-heating and electromagnetic radiation in modern electronic devices.Herein,we grew magnetic Fe_(3)O_(4)particles in situ on the MXene layer to obtain an MXene@Fe_(3)O_(4)composite with rich heterogeneous interfaces.Owing to the unique heterostructure and the synergistic effects of multiple electromagnetic wave absorption mechanisms,the composite achieved a minimum reflection loss of-27.14 dB and an effect-ive absorption bandwidth of 2.05 GHz at an absorption thickness of 2 mm.Moreover,the MXene@Fe_(3)O_(4)composite could be encapsu-lated in thermoplastic polyurethane(TPU)via thermal curing.The obtained composite elastomer exhibited a strong tensile strength,and its thermal diffusivity was 113%higher than that of pure TPU.Such additional mechanical properties and thermal conduction features render this composite elastomer an advanced electromagnetic absorber to adapt to the ever-changing environment for expanding practical applications.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2025B1515020077 and 2024A15150301-39)the National Natural Science Foundation of China(Grant No.12205138)the Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ2022-0530113206015).
文摘We present a minimal theoretical model for self-sustained oscillations of a thin elastic sheet on a hot plate,induced by thermomechanical coupling.As the plate temperature increases,the sheet’s static deflection becomes unstable via a Hopf bifurcation at a critical temperature TC,giving rise to spontaneous periodic motion.Linear stability analysis yields analytical expressions for the critical oscillation temperature TC and the oscillation period at onset.Numerical simulations of the nonlinear equations confirm the bifurcation and reveal how key parameters(stiffness,thermal softening,thermal coupling,etc.)govern the oscillation amplitude and waveform.Finally,we demonstrate that the self-oscillating sheet can perform mechanical work as a heat engine,and we compare its performance to the Carnot efficiency limit.This work provides design principles for thermally driven selfoscillators with potential applications in soft robotics,adaptive structures,and thermal energy harvesting.
基金financially supported by the National Natural Science Foundation of China(22408239)the National Natural Science Foundation of China(51904193)+3 种基金the Sichuan Science and Technology Program(2024NSFSC0987)the Fundamental Research Funds for the Central Universities(No.YJ202280)support from the Australian Research Council(ARC)through the ARC Linkage project(LP200200926)ARC Discover project(DP240102176)。
文摘The absence of efficient ion transport pathways in composite solid-state electrolytes(CSEs)usually results in low ionic conductivity,which remains a great challenge for developing solid-state lithiummetal batteries(SLMBs).Herein,we report achieving accelerated Li^(+)conduction in CSEs by a novel activation of the interfacial dipole layer.Polycationic ionic liquids and polyacrylonitrile with highly polar functional groups(-C≡N)are utilized to modulate the interfacial dipole layer in MOF-based CSEs,facilitating long-range pathways for the connectivity of Li^(+)conduction and enhancing rapid transport kinetics.The as-synthesized CSEs exhibit a high ionic conductivity of 0.59 mS cm^(-1)and a lithium transfer number of 0.85.The assembled SLMBs(Li/CSE/LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2))delivered a high-capacity retention of 88.7%with a minimal discharge voltage attenuation of 17.1 mV after 500 cycles(0.03 mV per cycle)at0.5 C.This work offers an effective approach to creating interpenetrating lithium-ion transport pathways with rapid ion transport kinetics for solid-state electrolytes,thereby advancing the development of solidstate lithium metal batteries.
基金Project supported by the Guangdong Basic and Applied Basic Research Foundation of China(No.2023A1515012809)the Natural Science Foundation of Shaanxi Province of China(No.2023-JC-YB-073)the Fundamental Research Funds for the Central Universities of China(No.D5000230066)。
文摘With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavior of materials in ultrashort time scales.Theoretically,generalized heat conductive models are considered in this work.By analogy with mechanical viscoelastic models,this paper further enriches the heat conduction models and gives their one-dimensional physical expression.Numerically,the transient thermoelastic response of the slim strip material under thermal shock is investigated by applying the proposed models.First,the analytical solution in the Laplace domain is obtained by the Laplace transform.Then,the numerical results of the transient responses are obtained by the numerical inverse Laplace transform.Finally,the transient responses of different models are analyzed and compared,and the effects of material parameters are discussed.This work not only opens up new research perspectives on generalized heat conductive and thermoelastic coupling theories,but also is expected to be beneficial for the deeper understanding of the heat wave theory.
基金supported by a National Research Foundation of Korea(NRF)Grant funded by the Ministry of Science and ICT(2021R1A2C1014294,2022R1A2C3003319)the BK21 FOUR(Fostering Outstanding Universities for Research)through the National Research Foundation(NRF)of Korea.
文摘A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety problems.Our study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves conductivity.mPR-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain dispersion.Integrating this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 cycles.In situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen reactions.Ex situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability tests.The present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.
文摘To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D frameworks,designated as[La(HPO_(3))(C_(2)O_(4))0.5(H_(2)O)_(2)](La‑1)and(C_(6)H_(16)N_(2))(H_(3)O)[La_(2)(H_(2)PO_(3))_(3)(C_(2)O_(4))_(3)(H_(2)O)](La‑2)(C_(6)H_(14)N_(2)=cis-2,6-dimethylpiperazine),were prepared by hydrothermal and solvothermal conduction,respectively.La‑1 was constructed with lanthanum phosphite 2D layers and C_(2)O_(4)^(2-)groups,whereas La‑2 was constructed with lanthanum oxalate 2D layers and H_(2)PO^(3-)groups.Alternating current(AC)impedance spectra indicate that the pro-ton conductivities of both compounds could reach 10^(-4)S·cm^(-1)and remain highly durable at 75℃and 98%of rela-tive humidity(RH).Due to the abundance of H-bonds in La‑2,theσof La‑2 was higher than that of La‑1.La‑1 exhibited excellent water and pH stability.CCDC:2439965,La‑1;443776,La‑2.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFB1714600)the National Natural Science Foundation of China(Grant No.52175095)the Young Top-Notch Talent Cultivation Program of Hubei Province of China.
文摘This paper examined how microstructure influences the homogenized thermal conductivity of cellular structures and revealed a surface-induced size-dependent effect.This effect is linked to the porous microstructural features of cellular structures,which stems from the degree of porosity and the distri-bution of the pores.Unlike the phonon-driven surface effect at the nanoscale,the macro-scale surface mechanism in thermal cellular structures is found to be the microstructure-induced changes in the heat conduction path based on fully resolved 3D numerical simulations.The surface region is determined by the microstructure,characterized by the intrinsic length.With the coupling between extrinsic and intrinsic length scales under the surface mechanism,a surface-enriched multiscale method was devel-oped to accurately capture the complex size-dependent thermal conductivity.The principle of scale separation required by classical multiscale methods is not necessary to be satisfied by the proposed multiscale method.The significant potential of the surface-enriched multiscale method was demon-strated through simulations of the effective thermal conductivity of a thin-walled metamaterial struc-ture.The surface-enriched multiscale method offers higher accuracy compared with the classical multiscale method and superior efficiency over high-fidelity finite element methods.
基金supported by the Postdoctoral Fellowship Program of CPSF(No.GZC20233005)the Fundamental Research Funds for the Central Universities(No.2024QN11025)+1 种基金the General Program of National Natural Science Foundation of China(No.52274243)the Hebei Province Natural Science Foundation Ecological Wisdom Mine Joint Fund Project(Nos.D2020402013 and D2022402040)。
文摘The water conductivity of karst collapsed column is affected by multiple factors such as the characteristics of its own column filling,structure and mining disturbance.As a structural water-conducting channel,fault usually plays a controlling role in hydrogeological structure.During the process of mine water hazard prevention and control,it was discovered that the lithology composition,compaction and cementation degree and water physical properties of karst collapsed column fillings were all non-conducting water,but due to the influence of combined development faults,some exploration drill holes showed concentrated water outflow.Based on this,the scientific hypothesis was proposed that fault cutting leads to water conduction in karst collapsed columns.The study comprehensively used methods like chronology,exploration data analysis,and hydrochemical testing to analyze the chronological relationship between faults and karst collapsed columns,their spatial relationship,outlet point distribution and water chemical properties,and the impact of faults on the water-conductivity of karst collapsed columns,which proved the effect of fault cutting on changing water conductivity of karst collapsed column.The research showed that later fault cutting through karst collapsed columns turned the originally non-conductive karst collapsed columns into water-conductive collapsed columns at the fault plane,creating a longitudinally connected water-conducting channel.A new model of fault cutting karst collapsed column to change the original water conductivity of karst collapsed column was proposed.The research results can provide a theoretical basis for the prediction of the water conductivity of the karst collapsed column.According to whether the karst collapsed column was cut by the fault,it was predicted theoretically,so as to determine the key areas of water conductivity detection and prevention and control,and has broad application prospects under the background of source control of mine water disaster.
基金supported by the National Natural Science Foundation of China(No.52203261,No.52473213)。
文摘Solid polymer electrolytes(SPEs)are considered one of the most promising materials for all-solid-state lithium metal batteries(ASSLMBs)due to their facile processability.However,developing SPEs with both high ionic conductivity and interfacial stability remains a challenge.Here,a donor-acceptor(D-A)like solid plasticizer,tris(pentafluorophenyl)borane(TPFPB),containing electron-rich F atoms and electrondeficient B sites,was introduced to regulate the ion transport behavior and interfacial chemistry of polyethylene oxide(PEO)-based SPEs.Owing to the multiple ion-dipole interactions(F Li^(+)TFSI^(-)and B TFSI^(-)Li^(+))between the TPFPB molecule and Li salts,a multimodal electrolyte environment featuring more free Li^(+)and trapped TFSI^(-)anions was generated,which cooperates with the reduced crystallinity of PEO,significantly facilitating the rapid migration of Li^(+).More importantly,TPFPB tends to be preferentially reduced to form a stable inorganic-rich solid electrolyte interphase on the Li-metal anode,ensuring uniform Li plating/stripping behavior.Thus,the TPFPB-modulated SPEs system achieves a high Li^(+)conductivity of 0.74 m S cm^(-1)and effectively suppresses dendrite growth,which enables a long-cycle dendrite-free Li/Li symmetric cell for over 5000 h,and remarkable electrochemical performance has been further validated in operational ASSLMBs.The findings in this work would inspire efforts to develop highperformance SPEs for all-solid-state alkali-metal batteries.
基金National Natural Science Foundation of China(Nos.92161111 and 21901038)Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,ChinaInternational Cooperation Fund of Science and Technology Commission of Shanghai Municipality,China(No.21130750100)。
文摘Highly reduced molybdenum red(MR)clusters have emerged as a new type of polyoxomolybdates(POMos)and showed great potential as electron/proton reservoirs for energy conversion and storage,as well as for catalysis.However,the limited structural diversity of MR clusters significantly hinders further exploration of their potential as functional materials.Herein,we describe the synthesis of a novel highly reduced MR cluster{Mo_(49)}(compound 1)based on rational assembly of a variety of basic building blocks(BBs).In addition to the well-established BBs found in the family of MR clusters,the unique tetrahedral{MoVI 4}BB plays a key role in directing the assembly to afford trigonal pyramid-like structure of compound 1,which consists of 49 Mo and 148 O atoms with a high reduction degree of 73%.Moreover,at 80℃and 98%relative humidity(RH),the pellet sample of compound 1 displays good proton conductivity of 7.88×10^(-3)S/cm owing to the efficient hydrogen-bonded network built from the surface oxygen atoms,protons and vip water molecules.This research offers new insights into the assembly and synthesis of MR clusters through a BB strategy and manifests their significant potential for advanced applications.
文摘The paper proposes an approximate solution to the classical (parabolic) multidimensional 2D and 3D heat conduction equation for a 5 × 5 cm aluminium plate and a 5 × 5 × 5 cm aluminum cube. An approximate solution of the generalized (hyperbolic) 2D and 3D equation for the considered plate and cube is also proposed. Approximate solutions were obtained by applying calculus of variations and Euler-Lagrange equations. In order to verify the correctness of the proposed approximate solutions, they were compared with the exact solutions of parabolic and hyperbolic equations. The paper also presents the research on the influence of time parameters τ as well as the relaxation times τ ∗ to the variation of the profile of the temperature field for the considered aluminum plate and cube.
文摘Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.
基金the financial support from the National Natural Science Foundation of China(Nos.21971039 and 22171045)and the Key Program of Natural Science Foundation of Fujian Province(No.2021J02007).
文摘The development of core-shell nanoclusters with controllable composition is of utmost importance as the material properties depend on their constituent elements.However,precisely tuning their compositions at the atomic scale is not easily achieved because of the difficulty of using limited macroscopic synthetic methods for atomic-level modulation.In this work,we report an interesting example of precisely regulating the core composition of an inorganic core-shell-type cobalt polyoxoniobate[Co_(26)Nb_(36)O_(140)]^(32−)by controlling reaction conditions,in which the inner Co-core composition could be tune while retaining the outer Nb-shell composition of resulting product,leading to a series of isostructural species with a general formula of{Co_(26-n)Nb_(36+n)O_(140)}(n=0–2).These rare species not only can display good powder and single-crystal proton conductivities,but also might provide helpful and atomic-level insights into the syntheses,structures and composition modifications of inorganic amorphous core-shell heterometal oxide nanoparticles.
