Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily ...Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states.展开更多
BACKGROUND Endoscopic rubber band ligation(ERBL)is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural pain.AIM To evaluate satisfaction,long-...BACKGROUND Endoscopic rubber band ligation(ERBL)is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural pain.AIM To evaluate satisfaction,long-term recurrence,and post-procedural pain in managing internal hemorrhoids using a combination of polidocanol foam sclerotherapy and ERBL.METHODS This was a prospective,multicenter,randomized study.A total of 195 consecutive patients diagnosed with grade II-III internal hemorrhoids were enrolled from four tertiary hospitals and randomly divided into a cap-assisted endoscopic polidocanol foam sclerobanding(EFSB)or an ERBL group.All patients were followed-up for 12 months.Symptom-based severity and post-procedural pain were assessed using a hemorrhoid severity score(HSS)and a visual analog scale(VAS).Continuous variables were reported as medians and interquartile range.RESULTS One hundred and ninety-five patients were enrolled,with 98 in the EFSB group.HSS was lower in the EFSB group than in the ERBL group at 8 weeks[4.0(3.0-5.0)vs 5.0(4.0-6.0),P=0.003]and 12-month[2.0(1.0-3.0)vs 3.0(2.0-3.0),P<0.001]of follow-up.The prolapse recurrence rate was lower in the EFSB group at 12 months(11.2%vs 21.6%,P=0.038).Multiple linear regression analysis demonstrated that EFSB treatment[B=-0.915,95%confidence interval(CI):−1.301 to−0.530,P=0.001]and rubber band number(B=0.843,95%CI:0.595-1.092,P<0.001)were negatively and independently associated with the VAS score 24 hours post-procedure.The median VAS was lower in the EFSB group than in the ERBL[2.0(1.0-3.0)vs 3.0(2.0-4.0),P<0.001].CONCLUSION Cap-assisted EFSB provided long-term satisfaction and effective relief from the recurrence of prolapse and pain 24 hours post-procedure.展开更多
Kagome materials are a class of material with a lattice structure composed of corner-sharing triangles that produce various exotic electronic phenomena,such as Dirac fermions,van Hove singularities,and flat bands.Howe...Kagome materials are a class of material with a lattice structure composed of corner-sharing triangles that produce various exotic electronic phenomena,such as Dirac fermions,van Hove singularities,and flat bands.However,most of the known kagome materials have a flat band detached from the Fermi energy,which limits the investigation of the emergent flat band physics.In this work,by combining soft x-ray angle-resolved photoemission spectroscopy(ARPES)and the first-principles calculations,the electronic structure is investigated of a novel kagome metal CeNi_(5) with a clear dispersion along the kz direction and a Fermi level flat band in theΓ–K–M–Γplane.Besides,resonant ARPES experimental results indicate that the valence state of Ce ions is close to 4^(+),which is consistent with the transport measurement result.Our results demonstrate the unique electronic properties of CeNi_(5) as a new kagome metal and provide an ideal platform for exploring the flat band physics and the interactions between different types of flat bands by tuning the valence state of Ce ions.展开更多
Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is a...Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency.展开更多
We have read the article by Qu et al with great interest,as it presents an inte-gration of endoscopic polidocanol foam sclerotherapy with rubber band ligation in patients with Grade Ⅱ-Ⅲ internal hemorrhoids.The auth...We have read the article by Qu et al with great interest,as it presents an inte-gration of endoscopic polidocanol foam sclerotherapy with rubber band ligation in patients with Grade Ⅱ-Ⅲ internal hemorrhoids.The authors conducted a prospective,multicenter,randomized study to evaluate the long-term sympto-matic and endoscopic efficacy of this combined intervention.In this discussion,we focus on the procedural steps of this combined strategy and suggest potential avenues for future research.展开更多
Hemorrhoids are a common and painful condition,with conventional treatments such as endoscopic rubber band ligation(ERBL)and injection sclerotherapy often falling short due to high recurrence rates and significant pos...Hemorrhoids are a common and painful condition,with conventional treatments such as endoscopic rubber band ligation(ERBL)and injection sclerotherapy often falling short due to high recurrence rates and significant post-operative pain.A clinical trial by Qu et al introduces a novel approach called endoscopic polidocanol foam sclerobanding(EFSB).This multicenter randomized trial involved 195 patients with grade II and III internal hemorrhoids and demonstrated that EFSB significantly reduced recurrence rates and post-procedural pain while improving symptom relief and patient satisfaction compared to ERBL.The study's strengths include its robust design,comprehensive outcome evaluation,and patient-centered approach.Despite limitations such as the single-blind design and relatively short follow-up period,the findings suggest that EFSB could enhance clinical practice by offering a more effective and patient-friendly treatment option.Further research is needed to validate these results and explore the long-term benefits and cost-effectiveness of EFSB.展开更多
BACKGROUND According to practice guidelines,endoscopic band ligation(EBL)and endoscopic tissue adhesive injection(TAI)are recommended for treating bleeding from esophagogastric varices.However,EBL and TAI are known to...BACKGROUND According to practice guidelines,endoscopic band ligation(EBL)and endoscopic tissue adhesive injection(TAI)are recommended for treating bleeding from esophagogastric varices.However,EBL and TAI are known to cause serious complications,such as hemorrhage from dislodged ligature rings caused by EBL and hemorrhage from operation-related ulcers resulting from TAI.However,the optimal therapy for mild to moderate type 1 gastric variceal hemorrhage(GOV1)has not been determined.Therefore,the aim of this study was to discover an individualized treatment for mild to moderate GOV1.AIM To compare the efficacy,safety and costs of EBL and TAI for the treatment of mild and moderate GOV1.METHODS A clinical analysis of the data retrieved from patients with mild or moderate GOV1 gastric varices who were treated under endoscopy was also conducted.Patients were allocated to an EBL group or an endoscopic TAI group.The differences in the incidence of varicose relief,operative time,operation success rate,mortality rate within 6 wk,rebleeding rate,6-wk operation-related ulcer healing rate,complication rate and average operation cost were compared between the two groups of patients.RESULTS The total effective rate of the two treatments was similar,but the efficacy of EBL(66.7%)was markedly better than that of TAI(39.2%)(P<0.05).The operation success rate in both groups was 100%,and the 6-wk mortality rate in both groups was 0%.The average operative time(26 min)in the EBL group was significantly shorter than that in the TAI group(46 min)(P<0.01).The rate of delayed postoperative rebleeding in the EBL group was significantly lower than that in the TAI group(11.8%vs 45.1%)(P<0.01).At 6 wk after the operation,the healing rate of operation-related ulcers in the EBL group was 80.4%,which was significantly greater than that in the TAI group(35.3%)(P<0.01).The incidence of postoperative complications in the two groups was similar.The average cost and other related economic factors were greater for the EBL than for the TAI(P<0.01).CONCLUSION For mild to moderate GOV1,patients with EBL had a greater one-time varix eradication rate,a greater 6-wk operation-related ulcer healing rate,a lower delayed rebleeding rate and a lower cost than patients with TAI.展开更多
A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 Hz.To broaden the ban...A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 Hz.To broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated,which produce two ultra-wide band gaps(approximately 5116 Hz and 6027 Hz,respectively).The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic wave.The impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are studied.Decreasing the concave angle leads to an increase in the width of the widest band gap,and the width of the widest band gap increases as the resonator radius of the two-phase SCM increases.Additionally,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces,wave propagation directions,group velocities,and phase velocities.Ultimately,the analysis focuses on the transmission properties of finite periodic structures.The solid single-phase SCM achieves a maximum vibration attenuation over 800,while the width of the band gap is smaller than that of the two-phase SCM.Both metamaterials exhibit high vibration attenuation capabilities,which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.展开更多
Ru-based superconductor LaRu_(2)As_(2) has been discovered exhibiting the highest critical temperature of ~ 7.8 K among iron-free transition metal pnictides with the ThCr_(2)Si_(2)-type crystal structure. However, mic...Ru-based superconductor LaRu_(2)As_(2) has been discovered exhibiting the highest critical temperature of ~ 7.8 K among iron-free transition metal pnictides with the ThCr_(2)Si_(2)-type crystal structure. However, microscopic research on this novel superconducting material is still lacking. Here, we utilize scanning tunneling microscopy/spectroscopy to uncover the superconductivity and surface structure of LaRu_(2)As_(2). Two distinct terminating surfaces are identified on the cleaved crystals, namely, the As surface and the La surface. Atomic missing line defects are observed on the La surface. Both surfaces exhibit a superconducting gap of ~ 1.0 me V. By employing quasiparticle interference techniques, we observe standing wave patterns near the line defects on the La atomic plane. These patterns are attributed to quasiparticle scattering from two electron type parabolic bands.展开更多
High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerat...High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerating the movement of the overlying sliding mass.To quantitatively investigate this complex multiphysical phenomenon,we established a set of equations that describe the variations in temperature and excess pore pressure within the shear band,as well as the conservation of momentum equation for the overlying sliding mass.With a simplified landslide model,we investigated the variations of temperature and excess pore pressure within the shear band and their impacts on the velocity of the overlying sliding mass.On this basis,we studied the impact of seven key parameters on the maximum temperature and excess pore pressure in the shear band,as well as the impact on the velocity of the overlying sliding mass.The simulation results of the standard model show that the temperature and excess pore pressure in the shear band are significantly higher than those in the adjacent areas,and reach the maximum values in the center.Within a few seconds after the start,the maximum excess pore pressure in the shear zone is close to the initial stress,and the shear strength loss rate exceeds 90%.The thermal pressurization mechanism significantly increases the velocity of the overlying sliding mass.The results of parameter sensitivity analysis show that the thermal expansion coefficient has the most significant impact on the temperature and excess pore pressure in the shear band,and the sliding surface dip angle has the most significant impact on the velocity of the overlying sliding mass.The results of this study are of great significance for clarifying the mechanism of thermal pressurization-induced high-speed sliding.展开更多
The Floquet technology,a powerful way to manipulate quantum states,is employed to drive sidebands transition under large detuning.Our results demonstrate that high fidelities over 99%can be achieved through optimizing...The Floquet technology,a powerful way to manipulate quantum states,is employed to drive sidebands transition under large detuning.Our results demonstrate that high fidelities over 99%can be achieved through optimizing suitable modulation frequencies under large detuning.We observe high-fidelity transitions within a high bandwidth by utilizing a single modulation frequency and reveal that this capability is due to the emergence of a flat-band structure in the bandwidth range.The key finding of high-fidelity sideband manipulation under large detuning is experimentally confirmed in nuclear magnetic resonance platform.Finally,we propose a new parallel sideband cooling scheme that enables simultaneous cooling of multiple motional modes.This approach improves the cooling rate compared to conventional schemes with fixed laser frequency and power,and eliminates the need for mode-specific addressing.Our Floquet parallel scheme is applicable to any harmonic oscillator system and is not limited by bandwidth in theory.展开更多
We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on th...We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems.展开更多
Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include ele...Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include elemental filling to regulate the band.However,the influence of the most electronegative fluorine on the CoSb_(3) band remains unclear.We carry out density-functional-theory calculations and show that the valence band maximum gradually shifts downward with the increase of fluorine filling,lastly the valence band maximum converges to the highly degenerated secondary valence bands in fluorine-filled skutterudites.展开更多
The seismic performance of rubber concrete-layered periodic foundations are significantly influenced by their design,in which the band gaps play a paramount role.Aiming at providing better designs for these foundation...The seismic performance of rubber concrete-layered periodic foundations are significantly influenced by their design,in which the band gaps play a paramount role.Aiming at providing better designs for these foundations,this study first proposes and validates the analytical formulas to approximate the bounds of the first few band gaps.In addition,the mapping relations linking the frequencies of different band gaps are presented.Furthermore,an optimal design method for these foundations is developed,which is validated through an engineering example.It is demonstrated that ensuring the superstructure’s resonance zones are completely covered by the corresponding periodic foundation’s band gaps can achieve satisfactory vibration attenuation effects,which is a good strategy for the design of rubber concrete layered periodic foundations.展开更多
We report the growth of high-quality single crystals of RhP_(2),and systematically study its structure and physical properties by transport,magnetism,and heat capacity measurements.Single-crystal x-ray diffraction rev...We report the growth of high-quality single crystals of RhP_(2),and systematically study its structure and physical properties by transport,magnetism,and heat capacity measurements.Single-crystal x-ray diffraction reveals that RhP_(2) adopts a monoclinic structure with the cell parameters a=5.7347(10)A,b=5.7804(11)A,and c=5.8222(11)A,space group P2_(1)/c(No.14).The electrical resistivityρ(T)measurements indicate that RhP_(2) exhibits narrow-bandgap behavior with the activation energies of 223.1 meV and 27.4 meV for two distinct regions,respectively.The temperaturedependent Hall effect measurements show electron domain transport behavior with a low charge carrier concentration.We find that RhP_(2) has a high mobilityμ_(e)~210 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_(e)~3.3×10^(18)cm^(3) at 300 K with a narrow-bandgap feature.The high mobilityμ_(e) reaches the maximum of approximately 340 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_^(e)~2×10^(18)cm^(-3)at 100 K.No magnetic phase transitions are observed from the susceptibilityχ(T)and specific heat C_(p)(T)measurements of RhP_(2).Our results not only provide effective potential as a material platform for studying exotic physical properties and electron band structures but also motivate further exploration of their potential photovoltaic and optoelectronic applications.展开更多
Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density ...Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various substrates.Based on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:1.All of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and PABA.The sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping capacity.The outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.展开更多
Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands.We theoretically investigate the evolution of electronic band structures of kagome lattices...Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands.We theoretically investigate the evolution of electronic band structures of kagome lattices in response to uniaxial strain using both a tight-binding model and an antidot model based on a periodic muffin-tin potential.It is found that the Dirac points move with applied strain.Furthermore,the flat band of unstrained kagome lattices is found to develop into a highly anisotropic shape under a stretching strain along y direction,forming a partially flat band with a region dispersionless along ky direction while dispersive along kx direction.Our results shed light on the possibility of engineering the electronic band structures of kagome materials by mechanical strain.展开更多
Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynam...Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time.展开更多
In the study,we comment on the article by Qu et al.Internal hemorrhoids are the most common anorectal disorders worldwide with bleeding,prolapse,and difficulty in defecation.Endoscopic rubber band ligation(ERBL)is a s...In the study,we comment on the article by Qu et al.Internal hemorrhoids are the most common anorectal disorders worldwide with bleeding,prolapse,and difficulty in defecation.Endoscopic rubber band ligation(ERBL)is a safe,convenient,quick,and economical outpatient procedure.The main goal of ERBL is to alleviate prolapse,but the high incidence of recurrence and post-procedural pain are of clinical concern.Polidocanol foam as a local hemostatic and anesthetic agent could reduce the rates of post-procedural pain and bleeding.Endoscopic polidocanol foam sclerobanding(EFSB)is a novel approach that could lift the mucosa for easy ligation and promote increased scarring in the submucosal tissue which translates into long-term relief from prolapse recurrence and reduced 24-h postprocedural pain.The study by Qu et al is a novel multi-center prospective randomized study to compare ERBL and EFSB in patients with grades II and III internal hemorrhoids with one-year follow-up.Results showed that EFSB is a novel therapy for internal hemorrhoids,but future studies with a larger sample,multiple treatment sessions,and long-term follow-up are required to confirm these findings.展开更多
Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-form...Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-formed fault.Digital image correlation and acoustic emission(AE)techniques were used to monitor the evolution of shear bands at the rock bridge area and microcracking behaviors.The experimental results revealed that the shear stresses corresponding to the peak and sub-peak in the stressdisplacement curve are significantly affected by the normal stress.Strain localization bands emerged at both the tip of joints and the rock bridge,and their extension and interaction near the peak stress caused a surge in the AE hit rate and a significant decrease in the AE b value.Short and curvilinear strain bands were detected at low normal stress,while high normal stress generally led to more microcracking events and longer coplanar cracks at the rock bridge area.Furthermore,an increase in normal stress resulted in a higher AE count rate and more energetic AE events during friction sliding along the shearformed fault.It was observed that the elastic energy released during the crack coalescence at the prepeak stage was much greater than that released during friction sliding at the post-peak stage.More than 75%of AE events were located in the low-frequency band(0e100 kHz),and this proportion continued to rise with increasing normal stress.Moreover,more AE events of low AF value and high RA value were observed in specimens subjected to high normal stress,indicating that greater normal stress led to more microcracks of shear nature.展开更多
基金This research was financially supported by the Science and Technology Department of Sichuan Province Project,China(Grant Nos.2022YFSY0007,2021YFH0010)the National Scientific Science Foundation of China(Grant No.U20A20266).
文摘Great potential of underground gas/energy storage in salt caverns seems to be a promising solution to support renewable energy.In the underground storage method,the operating cycle unfortunately may reach up to daily or even hourly,which generates complicated pressures on the salt cavern.Furthermore,the mechanical behavior of rock salt may change and present distinct failure characteristics under different stress states,which affects the performance of salt cavern during the time period of full service.To reproduce a similar loading condition on the cavern surrounding rock mass,the cyclic triaxial loading/unloading tests are performed on the rock salt to explore the mechanical transition behavior and failure characteristics under different confinement.Experimental results show that the rock salt samples pre-sent a diffused shear failure band with significant bulges at certain locations in low confining pressure conditions(e.g.5 MPa,10 MPa and 15 MPa),which is closely related to crystal misorientation and grain boundary sliding.Under the elevated confinement(e.g.20 MPa,30 MPa and 40 MPa),the dilation band dominates the failure mechanism,where the large-size halite crystals are crushed to be smaller size and new pores are developing.The failure transition mechanism revealed in the paper provides additional insight into the mechanical performance of salt caverns influenced by complicated stress states.
基金Supported by the Hospital Funded Clinical Research of Xinhua Hospital,No.19XHCR16D.
文摘BACKGROUND Endoscopic rubber band ligation(ERBL)is a nonsurgical technique for the treatment of symptomatic internal hemorrhoids but is limited by recurrence and post-procedural pain.AIM To evaluate satisfaction,long-term recurrence,and post-procedural pain in managing internal hemorrhoids using a combination of polidocanol foam sclerotherapy and ERBL.METHODS This was a prospective,multicenter,randomized study.A total of 195 consecutive patients diagnosed with grade II-III internal hemorrhoids were enrolled from four tertiary hospitals and randomly divided into a cap-assisted endoscopic polidocanol foam sclerobanding(EFSB)or an ERBL group.All patients were followed-up for 12 months.Symptom-based severity and post-procedural pain were assessed using a hemorrhoid severity score(HSS)and a visual analog scale(VAS).Continuous variables were reported as medians and interquartile range.RESULTS One hundred and ninety-five patients were enrolled,with 98 in the EFSB group.HSS was lower in the EFSB group than in the ERBL group at 8 weeks[4.0(3.0-5.0)vs 5.0(4.0-6.0),P=0.003]and 12-month[2.0(1.0-3.0)vs 3.0(2.0-3.0),P<0.001]of follow-up.The prolapse recurrence rate was lower in the EFSB group at 12 months(11.2%vs 21.6%,P=0.038).Multiple linear regression analysis demonstrated that EFSB treatment[B=-0.915,95%confidence interval(CI):−1.301 to−0.530,P=0.001]and rubber band number(B=0.843,95%CI:0.595-1.092,P<0.001)were negatively and independently associated with the VAS score 24 hours post-procedure.The median VAS was lower in the EFSB group than in the ERBL[2.0(1.0-3.0)vs 3.0(2.0-4.0),P<0.001].CONCLUSION Cap-assisted EFSB provided long-term satisfaction and effective relief from the recurrence of prolapse and pain 24 hours post-procedure.
基金Project support by the Science Fund from Shanghai Committee of Science and Technology,China (Grant No.23JC1403300)the Shanghai Municipal Science and Technology Major Project,China+3 种基金the TDLI Starting up Grant,the National Natural Science Foundation of China (Grant Nos.12374063,12204223,and 23Z990202580)the Fund from the Ministry of Science and Technology of China (Grant No.2023YFA1407400)the Shanghai Natural Science Fund for Original Exploration Program,China (Grant No.23ZR1479900)Shanghai Talent Program,China。
文摘Kagome materials are a class of material with a lattice structure composed of corner-sharing triangles that produce various exotic electronic phenomena,such as Dirac fermions,van Hove singularities,and flat bands.However,most of the known kagome materials have a flat band detached from the Fermi energy,which limits the investigation of the emergent flat band physics.In this work,by combining soft x-ray angle-resolved photoemission spectroscopy(ARPES)and the first-principles calculations,the electronic structure is investigated of a novel kagome metal CeNi_(5) with a clear dispersion along the kz direction and a Fermi level flat band in theΓ–K–M–Γplane.Besides,resonant ARPES experimental results indicate that the valence state of Ce ions is close to 4^(+),which is consistent with the transport measurement result.Our results demonstrate the unique electronic properties of CeNi_(5) as a new kagome metal and provide an ideal platform for exploring the flat band physics and the interactions between different types of flat bands by tuning the valence state of Ce ions.
基金supported by the National Natural Science Foundation of China(Nos.12164032 and 11964026)the Natural Science Foundation of Inner Mongolia(No.2019MS01010)+3 种基金Scientific Research Projects in Colleges and Universities in Inner Mongolia(No.NJZZ19145)Graduate Science Innovative Research Projects(No.S20210281Z)the Natural Science Foundation of Inner Mongolia(No.2022MS01014)Doctor Research Start-up Fund of Inner Mongolia Minzu University(No.BS625).
文摘Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency.
文摘We have read the article by Qu et al with great interest,as it presents an inte-gration of endoscopic polidocanol foam sclerotherapy with rubber band ligation in patients with Grade Ⅱ-Ⅲ internal hemorrhoids.The authors conducted a prospective,multicenter,randomized study to evaluate the long-term sympto-matic and endoscopic efficacy of this combined intervention.In this discussion,we focus on the procedural steps of this combined strategy and suggest potential avenues for future research.
文摘Hemorrhoids are a common and painful condition,with conventional treatments such as endoscopic rubber band ligation(ERBL)and injection sclerotherapy often falling short due to high recurrence rates and significant post-operative pain.A clinical trial by Qu et al introduces a novel approach called endoscopic polidocanol foam sclerobanding(EFSB).This multicenter randomized trial involved 195 patients with grade II and III internal hemorrhoids and demonstrated that EFSB significantly reduced recurrence rates and post-procedural pain while improving symptom relief and patient satisfaction compared to ERBL.The study's strengths include its robust design,comprehensive outcome evaluation,and patient-centered approach.Despite limitations such as the single-blind design and relatively short follow-up period,the findings suggest that EFSB could enhance clinical practice by offering a more effective and patient-friendly treatment option.Further research is needed to validate these results and explore the long-term benefits and cost-effectiveness of EFSB.
基金Supported by the Guizhou Provincial Science and Technology Program,No.[2020]4Y004.
文摘BACKGROUND According to practice guidelines,endoscopic band ligation(EBL)and endoscopic tissue adhesive injection(TAI)are recommended for treating bleeding from esophagogastric varices.However,EBL and TAI are known to cause serious complications,such as hemorrhage from dislodged ligature rings caused by EBL and hemorrhage from operation-related ulcers resulting from TAI.However,the optimal therapy for mild to moderate type 1 gastric variceal hemorrhage(GOV1)has not been determined.Therefore,the aim of this study was to discover an individualized treatment for mild to moderate GOV1.AIM To compare the efficacy,safety and costs of EBL and TAI for the treatment of mild and moderate GOV1.METHODS A clinical analysis of the data retrieved from patients with mild or moderate GOV1 gastric varices who were treated under endoscopy was also conducted.Patients were allocated to an EBL group or an endoscopic TAI group.The differences in the incidence of varicose relief,operative time,operation success rate,mortality rate within 6 wk,rebleeding rate,6-wk operation-related ulcer healing rate,complication rate and average operation cost were compared between the two groups of patients.RESULTS The total effective rate of the two treatments was similar,but the efficacy of EBL(66.7%)was markedly better than that of TAI(39.2%)(P<0.05).The operation success rate in both groups was 100%,and the 6-wk mortality rate in both groups was 0%.The average operative time(26 min)in the EBL group was significantly shorter than that in the TAI group(46 min)(P<0.01).The rate of delayed postoperative rebleeding in the EBL group was significantly lower than that in the TAI group(11.8%vs 45.1%)(P<0.01).At 6 wk after the operation,the healing rate of operation-related ulcers in the EBL group was 80.4%,which was significantly greater than that in the TAI group(35.3%)(P<0.01).The incidence of postoperative complications in the two groups was similar.The average cost and other related economic factors were greater for the EBL than for the TAI(P<0.01).CONCLUSION For mild to moderate GOV1,patients with EBL had a greater one-time varix eradication rate,a greater 6-wk operation-related ulcer healing rate,a lower delayed rebleeding rate and a lower cost than patients with TAI.
基金supported by the National Natural Science Foundation of China(Nos.12372019,12072222,12132010,12021002,and 11991032)the Open Projects of State Key Laboratory for Strength and Structural Integrity of China(No.ASSIKFJJ202303002)+1 种基金the State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures of China(No.SKLTESKF1901)the Aeronautical Science Foundation of China(No.ASFC-201915048001)。
文摘A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 Hz.To broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated,which produce two ultra-wide band gaps(approximately 5116 Hz and 6027 Hz,respectively).The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic wave.The impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are studied.Decreasing the concave angle leads to an increase in the width of the widest band gap,and the width of the widest band gap increases as the resonator radius of the two-phase SCM increases.Additionally,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces,wave propagation directions,group velocities,and phase velocities.Ultimately,the analysis focuses on the transmission properties of finite periodic structures.The solid single-phase SCM achieves a maximum vibration attenuation over 800,while the width of the band gap is smaller than that of the two-phase SCM.Both metamaterials exhibit high vibration attenuation capabilities,which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.62488201 and 52072401)the National Key R&D Program of China(Grant No.2019YFA0308500)+1 种基金the Chinese Academy of Sciences(Grant No.YSBR-003)the Innovation Program of Quantum Science and Technology(Grant No.2021ZD0302700)。
文摘Ru-based superconductor LaRu_(2)As_(2) has been discovered exhibiting the highest critical temperature of ~ 7.8 K among iron-free transition metal pnictides with the ThCr_(2)Si_(2)-type crystal structure. However, microscopic research on this novel superconducting material is still lacking. Here, we utilize scanning tunneling microscopy/spectroscopy to uncover the superconductivity and surface structure of LaRu_(2)As_(2). Two distinct terminating surfaces are identified on the cleaved crystals, namely, the As surface and the La surface. Atomic missing line defects are observed on the La surface. Both surfaces exhibit a superconducting gap of ~ 1.0 me V. By employing quasiparticle interference techniques, we observe standing wave patterns near the line defects on the La atomic plane. These patterns are attributed to quasiparticle scattering from two electron type parabolic bands.
基金financed by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(No.SKLGP2023K022)the Natural Science Foundation of Hubei Province(No.2022CFA011).
文摘High-speed sliding often leads to catastrophic landslides,many of which,in the initial sliding phase before disintegration,experience a friction-induced thermal pressurization effect in the bottom shear band,accelerating the movement of the overlying sliding mass.To quantitatively investigate this complex multiphysical phenomenon,we established a set of equations that describe the variations in temperature and excess pore pressure within the shear band,as well as the conservation of momentum equation for the overlying sliding mass.With a simplified landslide model,we investigated the variations of temperature and excess pore pressure within the shear band and their impacts on the velocity of the overlying sliding mass.On this basis,we studied the impact of seven key parameters on the maximum temperature and excess pore pressure in the shear band,as well as the impact on the velocity of the overlying sliding mass.The simulation results of the standard model show that the temperature and excess pore pressure in the shear band are significantly higher than those in the adjacent areas,and reach the maximum values in the center.Within a few seconds after the start,the maximum excess pore pressure in the shear zone is close to the initial stress,and the shear strength loss rate exceeds 90%.The thermal pressurization mechanism significantly increases the velocity of the overlying sliding mass.The results of parameter sensitivity analysis show that the thermal expansion coefficient has the most significant impact on the temperature and excess pore pressure in the shear band,and the sliding surface dip angle has the most significant impact on the velocity of the overlying sliding mass.The results of this study are of great significance for clarifying the mechanism of thermal pressurization-induced high-speed sliding.
基金supported by the National Natural Science Foundation of China(Grant Nos.11904402,12174447,12074433,12004430,and 12174448)。
文摘The Floquet technology,a powerful way to manipulate quantum states,is employed to drive sidebands transition under large detuning.Our results demonstrate that high fidelities over 99%can be achieved through optimizing suitable modulation frequencies under large detuning.We observe high-fidelity transitions within a high bandwidth by utilizing a single modulation frequency and reveal that this capability is due to the emergence of a flat-band structure in the bandwidth range.The key finding of high-fidelity sideband manipulation under large detuning is experimentally confirmed in nuclear magnetic resonance platform.Finally,we propose a new parallel sideband cooling scheme that enables simultaneous cooling of multiple motional modes.This approach improves the cooling rate compared to conventional schemes with fixed laser frequency and power,and eliminates the need for mode-specific addressing.Our Floquet parallel scheme is applicable to any harmonic oscillator system and is not limited by bandwidth in theory.
基金Project supported by the National Natural Science Foundation of China (Grant No.12074367)Anhui Initiative in Quantum Information Technologies,the National Key Research and Development Program of China (Grant No.2020YFA0309804)+3 种基金Shanghai Municipal Science and Technology Major Project (Grant No.2019SHZDZX01)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDB35020200)Innovation Program for Quantum Science and Technology (Grant No.2021ZD0302002)New Cornerstone Science Foundation。
文摘We investigated the one-dimensional diamond ladder in the momentum lattice platform. By inducing multiple twoand four-photon Bragg scatterings among specific momentum states, we achieved a flat band system based on the diamond model, precisely controlling the coupling strength and phase between individual lattice sites. Utilizing two lattice sites couplings, we generated a compact localized state associated with the flat band, which remained localized throughout the entire time evolution. We successfully realized the continuous shift of flat bands by adjusting the corresponding nearest neighbor hopping strength, enabling us to observe the complete localization process. This opens avenues for further exploration of more complex properties within flat-band systems, including investigating the robustness of flat-band localized states in disordered flat-band systems and exploring many-body localization in interacting flat-band systems.
基金supported by the National Natural Science Foundation of China (Grant Nos.52171220,92163212,and 92163119)the Research Funding of Wuhan Polytechnic University (Grant No.2022RZ059)the National Innovation and Entrepreneurship Training Program for College Students (Grant No.S202310497202)。
文摘Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include elemental filling to regulate the band.However,the influence of the most electronegative fluorine on the CoSb_(3) band remains unclear.We carry out density-functional-theory calculations and show that the valence band maximum gradually shifts downward with the increase of fluorine filling,lastly the valence band maximum converges to the highly degenerated secondary valence bands in fluorine-filled skutterudites.
基金National Natural Science Foundation of China under Grant Nos.52078395 and 52178301the Open Projects Foundation of the State Key Laboratory for Health and Safety of Bridge Structures under Grant No.BHSKL19-07-GF+1 种基金the Dawn Program of Knowledge Innovation Project from the Bureau of Science and Technology of Wuhan Municipality under Grant No.2022010801020357the Science Research Foundation of Wuhan Institute of Technology under Grant No.K2021030。
文摘The seismic performance of rubber concrete-layered periodic foundations are significantly influenced by their design,in which the band gaps play a paramount role.Aiming at providing better designs for these foundations,this study first proposes and validates the analytical formulas to approximate the bounds of the first few band gaps.In addition,the mapping relations linking the frequencies of different band gaps are presented.Furthermore,an optimal design method for these foundations is developed,which is validated through an engineering example.It is demonstrated that ensuring the superstructure’s resonance zones are completely covered by the corresponding periodic foundation’s band gaps can achieve satisfactory vibration attenuation effects,which is a good strategy for the design of rubber concrete layered periodic foundations.
基金supported by the National Key Research and Development Program of China (Grant No.2017YFA0302901)the Strategic Priority Research Program,the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (Grant No.XDB33010100)+3 种基金the National Natural Science Foundation of China (Grant Nos.12134018,11921004,and 11634015)the Foundation of Quantum Science Center of Guangdong–Hong Kong–Macao Greater Bay Area,China (Grant No.QD2301005)the Postdoctoral Science Foundation of China (Grant No.2021M693370)the Synergetic Extreme Condition User Facility (SECUF)。
文摘We report the growth of high-quality single crystals of RhP_(2),and systematically study its structure and physical properties by transport,magnetism,and heat capacity measurements.Single-crystal x-ray diffraction reveals that RhP_(2) adopts a monoclinic structure with the cell parameters a=5.7347(10)A,b=5.7804(11)A,and c=5.8222(11)A,space group P2_(1)/c(No.14).The electrical resistivityρ(T)measurements indicate that RhP_(2) exhibits narrow-bandgap behavior with the activation energies of 223.1 meV and 27.4 meV for two distinct regions,respectively.The temperaturedependent Hall effect measurements show electron domain transport behavior with a low charge carrier concentration.We find that RhP_(2) has a high mobilityμ_(e)~210 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_(e)~3.3×10^(18)cm^(3) at 300 K with a narrow-bandgap feature.The high mobilityμ_(e) reaches the maximum of approximately 340 cm^(2)·V^(-1)·s^(-1)with carrier concentrations n_^(e)~2×10^(18)cm^(-3)at 100 K.No magnetic phase transitions are observed from the susceptibilityχ(T)and specific heat C_(p)(T)measurements of RhP_(2).Our results not only provide effective potential as a material platform for studying exotic physical properties and electron band structures but also motivate further exploration of their potential photovoltaic and optoelectronic applications.
基金Funded by the Sultan Idris Education University(UPSI)(No.2020-0256-103-02(FRGS/1/2020/STG07/UPSI/02/2))provided by the Ministry of Higher Education,Malaysia。
文摘Calix[n]arenes was utilized to detect PABA,the primary sunscreen component.This study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various substrates.Based on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:1.All of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and PABA.The sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping capacity.The outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11904261 and 11904259).
文摘Materials with kagome lattices have attracted significant research attention due to their nontrivial features in energy bands.We theoretically investigate the evolution of electronic band structures of kagome lattices in response to uniaxial strain using both a tight-binding model and an antidot model based on a periodic muffin-tin potential.It is found that the Dirac points move with applied strain.Furthermore,the flat band of unstrained kagome lattices is found to develop into a highly anisotropic shape under a stretching strain along y direction,forming a partially flat band with a region dispersionless along ky direction while dispersive along kx direction.Our results shed light on the possibility of engineering the electronic band structures of kagome materials by mechanical strain.
基金supported by the National Natural Science Foundation of China (Grant Nos.12164019,11991060,12088101,and U1930402)the Natural Science Foundation of Jiangxi Province of China (Grant No.20212BAB201017).
文摘Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time.
文摘In the study,we comment on the article by Qu et al.Internal hemorrhoids are the most common anorectal disorders worldwide with bleeding,prolapse,and difficulty in defecation.Endoscopic rubber band ligation(ERBL)is a safe,convenient,quick,and economical outpatient procedure.The main goal of ERBL is to alleviate prolapse,but the high incidence of recurrence and post-procedural pain are of clinical concern.Polidocanol foam as a local hemostatic and anesthetic agent could reduce the rates of post-procedural pain and bleeding.Endoscopic polidocanol foam sclerobanding(EFSB)is a novel approach that could lift the mucosa for easy ligation and promote increased scarring in the submucosal tissue which translates into long-term relief from prolapse recurrence and reduced 24-h postprocedural pain.The study by Qu et al is a novel multi-center prospective randomized study to compare ERBL and EFSB in patients with grades II and III internal hemorrhoids with one-year follow-up.Results showed that EFSB is a novel therapy for internal hemorrhoids,but future studies with a larger sample,multiple treatment sessions,and long-term follow-up are required to confirm these findings.
基金supported by the National Natural Science Foundation of China(Grant No.52125903).
文摘Direct shear tests were conducted on sandstone specimens under different constant normal stresses to study the coalescence of cracks between non-persistent flaws and the shear sliding characteristics of the shear-formed fault.Digital image correlation and acoustic emission(AE)techniques were used to monitor the evolution of shear bands at the rock bridge area and microcracking behaviors.The experimental results revealed that the shear stresses corresponding to the peak and sub-peak in the stressdisplacement curve are significantly affected by the normal stress.Strain localization bands emerged at both the tip of joints and the rock bridge,and their extension and interaction near the peak stress caused a surge in the AE hit rate and a significant decrease in the AE b value.Short and curvilinear strain bands were detected at low normal stress,while high normal stress generally led to more microcracking events and longer coplanar cracks at the rock bridge area.Furthermore,an increase in normal stress resulted in a higher AE count rate and more energetic AE events during friction sliding along the shearformed fault.It was observed that the elastic energy released during the crack coalescence at the prepeak stage was much greater than that released during friction sliding at the post-peak stage.More than 75%of AE events were located in the low-frequency band(0e100 kHz),and this proportion continued to rise with increasing normal stress.Moreover,more AE events of low AF value and high RA value were observed in specimens subjected to high normal stress,indicating that greater normal stress led to more microcracks of shear nature.
