Background Previous evidence suggests that methionine(Met)consumption can promote placental angiogenesis and improve fetal survival.To investigate the mechanisms by which increased levels of Met as hydroxyl-Met(OHMet)...Background Previous evidence suggests that methionine(Met)consumption can promote placental angiogenesis and improve fetal survival.To investigate the mechanisms by which increased levels of Met as hydroxyl-Met(OHMet)improve placental function,forty sows were divided into four groups and fed either a control diet,or diets supplemented with 0.15%OHMet,0.3%OHMet or 0.3%Met(n=10).Placentas were collected immediately after expulsion,and extracted proteins were analyzed by tandem mass tag based quantitative proteomic analysis.Results We found that 0.15%OHMet consumption significantly increased placental vascular density compared with the control.Proteomic analysis identified 5,136 proteins,87 of these were differentially expressed(P<0.05,|fold change|>1.2).Enriched pathways in the Kyoto Encyclopedia of Genes and Genomes for 0.15%OHMet vs.control and 0.15%OHMet vs.0.3%OHMet were glutathione metabolism;for 0.15%OHMet vs.0.3%Met,they were NOD-like receptor signaling and apoptosis.Further analysis revealed that 0.15%OHMet supplementation upregulated the protein expression of glutathione-S-transferase(GSTT1)in placentas and trophoblast cells compared with the control and 0.3%OHMet groups,upregulated thioredoxin(TXN)in placentas and trophoblast cells compared with the 0.3%OHMet and 0.3%Met groups,and decreased reactive oxygen species(ROS)levels in trophoblast cells compared with other groups.In contrast,sows fed 0.3%OHMet or 0.3%Met diets increased placental interleukin 1βlevels compared with the control,and upregulated the protein expression of complex I-B9(NDUFA3)compared with the 0.15%OHMet group.Furthermore,homocysteine,an intermediate in the trans-sulphuration pathway of Met,damaged placental function by inhibiting the protein expression of TXN,leading to apoptosis and ROS production.Conclusion Although dietary 0.15%OHMet supplementation improved placental angiogenesis and increased antioxidative capacity,0.3%OHMet or 0.3%Met supplementation impaired placental function by aggravating inflammation and oxidative stress,which is associated with cumulative homocysteine levels.展开更多
This study focuses on the impact of Gd^(3+),Sm^(3+),Er^(3+).Y^(3+),and Bi^(3+)multi-doping on the crystal structure,microscopic surface features,and ionic conductivity of cerium dioxide in the Ce_(1-x)(Gd_(1/5)Sm_(1/5...This study focuses on the impact of Gd^(3+),Sm^(3+),Er^(3+).Y^(3+),and Bi^(3+)multi-doping on the crystal structure,microscopic surface features,and ionic conductivity of cerium dioxide in the Ce_(1-x)(Gd_(1/5)Sm_(1/5)Er_(1/5)Y_(1/)_5Bi_(1/5))_(x)O_(2-δ)(GSEYB)system.This system holds promise as a solid electrolyte material for low and medium-temperature solid oxide fuel cells.The powders of Ce_(1-x)(Gd_(1/5)Sm_(1/5)Er_(1/5)Y_(1/5)Bi_(1/5))_(x)O_(2-δ)(x=0,0.10,0.15,0.20,0.25,0.30)were synthesized using the solid-phase reaction method.The GSEYB electrolytes were comprehensively investigated for their phase structure,microstructure,oxygen vacancy concentration,and ionic conductivity using X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),and impedance spectroscopy.XRD diffraction patterns confirm a cubic fluorite-type structure with Fm3m space groups in all multi-doped systems.After sintering at 1400℃for 10 h,the relative density of doped samples exceeds 96%.In terms of electrical properties,the Ce_(0.75)Gd_(0.05)Sm_(0.05)Er_(0.05)Y_(0.05)Bi_(0.05)O_(2-δ)(x=0.25)electrolyte exhibits the highest ionic conductivity(σ_(t)=4.45×10^(-2)S/cm)and the lowest activation energy(E_(a)=0.79 eV)at 800℃.The coefficient of thermal expansion of the developed electrolyte aligns well with that of the commonly used electrode materials.This compatibility positions it as a highly promising candidate for utilization as an electrolyte material in solid oxide fuel cells(SOFCs).展开更多
Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type...Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.展开更多
BACKGROUND Cardiopulmonary bypass(CPB)is a life-support technology widely used in surgery.Review articles reflect research advances in a certain topic or field within a certain period of time.AIM To perform a bibliome...BACKGROUND Cardiopulmonary bypass(CPB)is a life-support technology widely used in surgery.Review articles reflect research advances in a certain topic or field within a certain period of time.AIM To perform a bibliometric analysis of the review articles that focused on CPB for cardiovascular surgery.METHODS This study was based on a bibliometric analysis.Data were acquired from the Web of Science and basic bibliometric parameters were analyzed and visualized using VOSviewer and Excel.RESULTS We identified 141 review articles on CPB.Generally,the number of publications increased,and most of them were published in the 2010s(n=57,40.4%)and the 2020s(n=45,31.9%).There were 113(80.1%)narrative review articles,21(14.9%)meta-analysis studies and 7(5.0%)systematic review papers.The United States(n=25,17.7%)and China(n=21,14.9%)were the leading countries in terms of publication number.The articles were published in 98 different journals.The Journal of Cardiothoracic and Vascular Anesthesia(n=14,10.0%)and Perfusion-United Kingdom(n=11,7.8%)were preferred by the authors.The high-frequency keywords included inflammatory response,children,acute kidney injury,meta-analysis and off-pump,except for CPB and cardiac surgery.Inflammatory response had the closest relationship with CPB during cardiac surgery.The complications of CPB,including inflammatory response,kidney injury and ischemia,caught lots of concern.CONCLUSION The rapid increase of review papers shows that the research on CPB in cardiac surgery is increasingly being emphasized by scholars and clinical staff worldwide.Meta-analysis has been widely conducted to analyze clinical controversies and further guide clinical practice.Strategies to improving the outcomes of patients undergoing cardiac surgery with CPB are the hot spots in this field.展开更多
Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex in...Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex inverse problem that comes with ultrafast time-resolved imager requirements and substantial computational demands to extract information from the multi-bounce scattered light.Consequently,the echo signal always suffers from serious deterioration in both intensity and shape,leading to limited resolution and image contrast.Here,we propose a concept of vectorial digitelligent optics for high-resolution NLOS imaging to cancel the wall’s scattering and refocus the light onto hidden targets for enhanced echo.In this approach,the polarization and wavefront of the laser spot are intelligently optimized via a feedback algorithm to form a near-perfect focusing pattern through a random scattering wall.By raster scanning the focusing spot across the object’s surface within the optical-memory-effect range of the wall,we obtain nearly diffraction-limited NLOS imaging with an enhanced signal-to-noise ratio.Our experimental results demonstrate a resolution of 0.40 mm at a distance of 0.35 m,reaching the diffraction limit of the system.Furthermore,we demonstrate that the proposed method is feasible for various complex NLOS scenarios.Our methods may open an avenue for active imaging,communication,and laser wireless power transfer.展开更多
BACKGROUND Stereoelectroencephalography(SEEG)is a minimally invasive preoperative evaluation of drug-resistant focal epilepsies.Increasing preclinical data show that SEEG has tremendous diagnostic and therapeutic valu...BACKGROUND Stereoelectroencephalography(SEEG)is a minimally invasive preoperative evaluation of drug-resistant focal epilepsies.Increasing preclinical data show that SEEG has tremendous diagnostic and therapeutic value for epilepsy.There are currently many studies on SEEG.AIM To summarize the development and application of SEEG.METHODS We conducted a bibliometric analysis of research on SEEG from 2019 to 2023.We obtained publications on SEEG from the Web of Science Core Collection(WoSCC)database.Excel,VOSviewer,and CiteSpace were responsible for the analyses.A variety of bibliographic elements were collected,including annual publications,authors,countries/regions,journals,keywords,etc.RESULTS A total of 691 publications were included in this study.Professor Fabrice Bartolomei of Timone Hospital in France was the most productive and influential author in the field of SEEG,whereas the authors from the United States were the leaders in general.In addition,we found that deep learning and source localization in SEEG have been popular in recent years.CONCLUSION This study provides a comprehensive analysis of SEEG research and highlights the growing interest in SEEG and its deep learning and source localization.展开更多
The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)tran...The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)transition occurring near the superconducting dome.Identifying the type of DW order is crucial for understanding the origin of superconductivity in this system.However,owing to the presence of La4Ni3O10 and other intergrowth phases in La_(3)Ni_(2)O_(7-δ)samples,extracting the intrinsic information from the La_(3)Ni_(2)O_(7) phase is challenging.In this study,we employed ^(139)La nuclear quadrupole resonance(NQR)measurements to eliminate the influence of other structural phases in the sample and obtain microscopic insights into the DW transition in La_(3)Ni_(2)O_(7-δ).Below the DW transition temperature T_(DW)∼153 K,we observe a distinct splitting in the±5/2↔±7/2 transition of the NQR resonance peak at the La(2)site,while only a line broadening is seen in the±3/2↔±5/2 transition peak.Through further analysis of the spectra,we show that the line splitting is due to a unidirectional charge modulation.A magnetic line broadening is also observed below T_(DW),accompanied by a large enhancement of the spin-lattice relaxation rate,indicating the formation of magnetically ordered moments in the DW state.Our results suggest a simultaneous formation of charge-and spin-density wave orders in La_(3)Ni_(2)O_(7-δ),thereby offering critical insights into the electronic correlations in Ni-based superconductors.展开更多
The anisotropy and tension-compression asymmetry of rare-earth magnesium(Mg-RE) alloys have attracted significant attention.In this study,the room-temperature tensile anisotropy and tensioncompression asymmetry of the...The anisotropy and tension-compression asymmetry of rare-earth magnesium(Mg-RE) alloys have attracted significant attention.In this study,the room-temperature tensile anisotropy and tensioncompression asymmetry of the extruded Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy were investigated utilizing techniques such as optical microscopy(OM),electron backscatter diffraction(EBSD),and viscoplastic self-consistent(VPSC) modeling.Among the tensile samples,the TO sample(with axis parallel to extrusion direction) exhibits the greatest tensile yield strength(TYS) of 270 MPa and ultimate tensile strength(UTS) of 336 MPa,the T45 sample(with axis inclined at a 45° angle to extrusion direction) and T90 sample(with axis perpendicular to extrusion direction) exhibit lower TYS and UTS.The CO sample shows a slightly greater compressive yield strength(CYS) of 290 MPa.The ratio of TYS/CYS is approximately 1.07.This study significantly adjusts the VPSC hardening parameters through the Schmid factor of deformation mechanisms in Mg-RE alloy,particularly increasing the τ0(critical resolved shear stress,CRSS) and τ1values for basalslip and {10-12} twinning.The ratios of CRSS for other deformation mechanisms to basalslip are approximately as follows:CRSSTwin/CRSSBas=2,CRSSpri/CRSSBas≈2.7and CRSSPyr/CRSSBas≈3.3,while these ratios in traditional alloys are generally higher.The stress-strain curves and pole figures obtained from the modified VPSC model demonstrate excellent agreement with experimental results.According to the VPSC simulation results,the primary factor contributing to tensile anisotropy is the disparity in the activation levels of slip systems.The inclusion of rare-earth elements mitigates the tension-compression asymmetry by reducing the difference of CRSS between different deformation mechanisms.展开更多
The tension-compression asymmetry presents notable challenges for the application of magnesium alloys in many fields.In this study,the solid-solution treated Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy's tension-compression a...The tension-compression asymmetry presents notable challenges for the application of magnesium alloys in many fields.In this study,the solid-solution treated Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy's tension-compression asymmetry was examined using optical microscope(OM),x-ray diffraction(XRD),viscoplastic self-consistent(VPSC)modeling,and electron backscatter diffraction(EBSD).The VPSC hardening parameters were significantly adjusted based on the Schmid factor of deformation modes in rare earth magnesium(Mg-RE)alloy,which came from the EBSD data.Excellent agreement was found between the modified VPSC model's calculation results,especially the stress-strain curves and pole figures.The alloy exhibited good strength with a negligible tension-compression asymmetry and an impressive 0.98 ratio of compressive yield strength to tensile yield strength(CYS/TYS).The main cause could be attributed to the unusual texture of(11-20)<0001>in alloy,which eliminated the imbalance in tension and compression deformation by having a negative effect on the activation of{10-12}twinning in tensile and a positive effect in compressive deformation.The activation level of{10-12}twinning was 0.37 and 0.40calculated by VPSC model,in the plastic deformation of tension and compression,respectively;in the tensile and compression samples,the EBSD data indicated that approximately 31.9%and 31.1%(area proportion)of the grains were deformed with twins,respectively.Both tension and compression deformation showed the{10-12}twinning in the early stage of deformation,which transformed to{11-22}twinning in the later stage.The considerable activation of pyramidal during the later stages of deformation endowed the alloy with good ductility.展开更多
As smart contracts,represented by Solidity,become deeply integrated into the manufacturing industry,blockchain-based Digital Twins(DT)has gained momentum in recent years.Most of the blockchain infrastructures in wides...As smart contracts,represented by Solidity,become deeply integrated into the manufacturing industry,blockchain-based Digital Twins(DT)has gained momentum in recent years.Most of the blockchain infrastructures in widespread use today are based on the Proof-of-Work(PoW)mechanism,and the process of creating blocks is known as“mining”.Mining becomes increasingly difficult as the blockchain grows in size and the number of on-chain business systems increases.To lower the threshold of participation in the mining process,“mining pools”have been created.Miners can cooperate and share the mining rewards according to the hashrate they contributed to the pool.Stratum is the most widely used communication protocol between miners and mining pools.Its security is essential for the participants.In this paper,we propose two novel Man-In-The-Middle(MITM)attack schemes against Stratum,which allow attackers to steal miners'hashrate to any mining pool using hijacked TCP connections.Compared with existing attacks,our work is more secretive,more suitable for the real-world environment,and more harmful.The Proof-of-Concept(PoC)shows that our schemes work perfectly on most mining softwares and pools.Furthermore,we present a lightweight AI-driven approach based on protocol-level feature analysis to detect Stratum MITM for blockchain-based DTs.Its detection model consists of three layers:feature extraction layer,vectorization layer,and detection layer.Experiments prove that our detection approach can effectively detect Stratum MITM traffic with 98%accuracy.Our work alerts the communities and provides possible mitigation against these more hidden and profitable attack schemes.展开更多
During the crystallization of perovskite films,defects at Pb and I sites are generated,causing lattice mismatch and adversely affecting the performance of perovskite solar cells(PSCs).Herein,we introduced aπ-conjugat...During the crystallization of perovskite films,defects at Pb and I sites are generated,causing lattice mismatch and adversely affecting the performance of perovskite solar cells(PSCs).Herein,we introduced aπ-conjugated molecule with a dual-ring structure,namely CCA(3,4-ethylenedioxythiophene-2,5-dicarboxylic acid),as an additive to regulate the crystallization of perovskite films and passivate defects.As a bidentate Lewis base,CCA coordinates the bidentate carboxyl groups with free Pb^(2+)through the delocalized electrons of its conjugated ring.This coordination regulates lattice stress,repairs the 3D[PbI6]octahedra,stabilizes the perovskite framework,and guides the vertical orientation growth of grains.Simultaneously,the addition of CCA shifts the perovskite’s band structure towards p-type,achieving better energy-level alignment with the doped hole-transport layer(HTL)and suppressing non-radiative recombination.Consequently,the prepared CCA-doped single-junction devices exhibit an outstanding power conversion efficiency(PCE)of 24.90%,with a high open-circuit voltage(VOC)of 1.195,a high fill factor(FF)of 84.60%,and low FF loss.The optimized films and devices show enhanced long-term stability,retaining 80.1%of the initial efficiency after continuous illumination for 560 h.Additionally,a PCE of 21.6%was achieved in devices with a bandgap of 1.68 eV,which were further extended to perovskite/silicon tandem devices,achieving high-performance devices with PCEs of 30.96%(aperture area:1.05 cm^(2))and 25.96%(aperture area:20.06 cm^(2)).展开更多
Gas explosions are a frequent hazard in underground confined spaces in the process of urban development.Liquid sedimentary layers,commonly present in these environments,have not been sufficiently studied in terms of t...Gas explosions are a frequent hazard in underground confined spaces in the process of urban development.Liquid sedimentary layers,commonly present in these environments,have not been sufficiently studied in terms of their impact on explosion dynamics.This study aims to investigate how gas-liquid two-phase environments in confined underground spaces affect the explosion characteristics of natural gas.To achieve this,experiments are conducted to examine the propagation of natural gas explosions in water and diesel layers,focusing on the influence of liquid properties and the liquid fullness degree(Lx)on explosion behavior.The results indicate that the presence of a liquid layer after the initial ignition stage significantly attenuates both the peak overpressure and the rise speed of pressure,in comparison to the natural gas conditions.During the subsequent explosive reaction,the evaporation and combustion of the diesel surface resulted in a distinct double-peak pressure rise profile in the diesel layer,with the second peak notably exceeding the first peak.Under conditions with a liquid sedimentary layer,the flame propagation velocities range from 6.53 to 34.1 m/s,while the overpressure peaks vary between 0.157 and 0.255 MPa.The explosion duration in both the water and diesel layer environments is approximately twice as long as that of the natural gas explosion,although the underlying mechanisms differ.In the diesel layer,the prolonged explosion time is attributed to the evaporation and combustion of the diesel,while in the water layer,the flame propagation velocity is significantly reduced.Under the experimental conditions,the maximum explosion energy reached 7.15×10~6J,corresponding to a TNT equivalent of 1.7.The peak overpressure surpassed the threshold for human fatality as defined by overpressure standards,posing a potential risk of damage to large steel-frame structures.The explosion shockwave in diesel layer conditions(L_(d)=0%,5%,7.5%,12.5%)and water layer(L_(w)=12.5%)conditions is observed to be sufficient to damage earthquake-resistant reinforced concrete.This study investigates the impact of sediment layer thickness and composition on gas explosions,and evaluates the associated explosion energy to assess human injuries and structural damage in underground environments.The findings of this study provide a scientific reference for urban underground safety.展开更多
Background:Vascular thrombus is a common complication in cancer patients and can be classified as benign or neoplastic based on tumor cell presence.Conventional imaging modalities provide anatomical information but ex...Background:Vascular thrombus is a common complication in cancer patients and can be classified as benign or neoplastic based on tumor cell presence.Conventional imaging modalities provide anatomical information but exhibit limited specificity in distinguishing neoplastic from benign thrombi,prompting the evaluation of 2‐deoxy‐2‐[^(18)F]fluoro‐D‐glucose positron emission tomography/computed tomography([^(18)F]FDG PET/CT),which leverages metabolic differences for improved differentiation.In this study,the efficacy of[^(18)F]FDG PET/CT for differentiating neoplastic thrombus from benign thrombus was evaluated in patients with malignant tumors.Methods:Sixty‐five patients with histologically or clinically confirmed neoplastic or benign thrombus who underwent[^(18)F]FDG PET/CT were retrospectively enrolled.Both visual and semi‐quantitative analyses of the PET/CT scans were conducted.The difference in maximum standardized uptake value(SUVmax)between neoplastic and benign thrombus was assessed using a t‐test.Furthermore,receiver operating characteristics(ROC)analysis was performed to determine the optimal SUVmax threshold for differentiating neoplastic from benign thrombus.Results:Within the cohort,55 patients were diagnosed with neoplastic thrombus and 10 patients with benign thrombus.In the visual analysis,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of[^(18)F]FDG PET/CT for diagnosing neoplastic thrombus were 96.4%,90.0%,98.1%,81.8%,and 95.4%,respectively.In the semiquantitative analysis,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy for diagnosing neoplastic thrombus were 96.4%,100%,100%,83.3%,and 96.9%,respectively.The normalized SUVmax of neoplastic thrombus was significantly higher than that of benign thrombus(10.11�5.32 vs.2.21�0.51,p<0.001).The area under the ROC curves for visual assessment and semi‐quantitative analysis were 0.932 and 0.993,respectively.There was no statistically significant difference observed between these two assessment methods(p=0.317).Conclusions:[^(18)F]FDG PET/CT is capable of differentiating neoplastic thrombus from benign thrombus.Both visual and semiquantitative analyses demonstrated high diagnostic sensitivity,specificity,and accuracy.展开更多
The dominant lithofacies of reservoirs in the Barra Velha formation of the study area are grainstones,which exhibit strong heterogeneity,and the seismic responses of buildups are characterized by low relief,posing a s...The dominant lithofacies of reservoirs in the Barra Velha formation of the study area are grainstones,which exhibit strong heterogeneity,and the seismic responses of buildups are characterized by low relief,posing a substantial challenge in evaluating the factors controlling high-quality reservoir development.This study thoroughly investigated sedimentary facies and diagenetic processes based on petrological and geophysical data,and a semi-open-rimmed carbonate platform model was established to illustrate the lithofacies distribution pattern.Additionally,the diagenetic processes and their main controlling factors were analyzed,and an attempt was made to establish a diagenetic sequence.Our findings indicate that sedimentary processes control the distribution of lithofacies,while diagenesis ultimately determines the petrophysical properties.The lithofacies types are closely associated with depositional environments.Shrub-like stromatolites are more developed at the bench margin and inner slope,while spherulites occur preferentially in the bench interior and mid-slope environments.Laminites accumulate in profundal or bench interior facies,whereas grainstones are present across all depositional environments,although their components vary.Integrated seismic attributes revealed that the bench margin exhibits nearly circular features,representing favorable conditions for high-quality reservoir development.The primary diagenetic processes in the study area include meteoric diagenesis,chemical compaction,and possible hydrothermal activity.During the eodiagenetic phase,the dissolution of Mg-clays played a key role in the diagenesis of carbonate rocks in the Barra Velha formation.This process typically occurred at structural highs,where Mg-clays were replaced by calcite spherulites,silicates,and dolomite.Some grainstones developed dolomite rims around particles,enhancing their resistance to compaction and preserving primary porosity.In the mesodiagenetic phase,chemical compaction and hydrothermal activity often caused primary pores to be filled with mosaic or blocky calcite and macrocrystalline quartz,leading to reduced permeability and porosity.Although dissolution was common in the study area,its impact on increasing pore space was limited.This study aims to improve drilling success rates in high-quality reservoirs and enhance hydrocarbon discoveries in the study area while also contributing to a better understanding of the evolution and distribution of high-quality reservoirs in analogous lacustrine carbonate settings.展开更多
Based on the energy dissipation caused by consolidation deformation of the porous media under external force and migration of the internal suspended substances,a coupled multiphase-substance flow(CMF)model was establi...Based on the energy dissipation caused by consolidation deformation of the porous media under external force and migration of the internal suspended substances,a coupled multiphase-substance flow(CMF)model was established.This model introduced the new concepts,such as particle temperature and particle entropy,to describe energy dissipation at meso-level.This model used a potential energy density function and migration coefficients to establish the corresponding connection between the dissipative force and dissipative flow.This viewpoint unifies the deformation,seepage,and suspended substance migration of geotechnical materials under the framework of granular thermodynamics.It can reflect the evolution of effective stress in the solid matrix of multi-components in a particle-reorganized state,and considers the temperature driving effect.The proposed CMF model is validated using the experimental results under coupled migration of heavy metal ions(HMs)and suspended particles(SPs).The calculation results demonstrated that the CMF model can describe the flow process under the conditions of arbitrary changes in different suspended substance types,injection concentrations,and injection velocities.展开更多
Flexible piezoresistive pressure sensors have attracted much attention for applications in health monitoring and human-machine interfaces due to their simple device structures and easy-to-read signals.For practical ap...Flexible piezoresistive pressure sensors have attracted much attention for applications in health monitoring and human-machine interfaces due to their simple device structures and easy-to-read signals.For practical applications,the deployment of flexible pressure sensors characterized by high sensitivity and fast response time is imperative for the rapid and accurate detection and monitoring of tiny signals.Such capabilities are essential for facilitating immediate feedback and informed decision-making across a spectrum of contexts.Drawing lessons from the hypersensitive and fast-responding pressure sensing structures in the dragonfly’s neck(for stable imaging during its highly maneuverable flight),a Biomimetic Piezoresistive Pressure Sensor(BPPS)with exquisite mechanically interlocking sensing microstructures is developed.Each interlocking perceptual structure pair consists of an ox-horn-shaped and a mushroom-shaped structural unit.Through the characteristic configuration of the perceptual structure pair,the BPPS realizes a fast gradient accumulation of the contact area,thus synergistically enhancing the sensitivity and fast response capability.Remarkably,the sensitivity of the BPPS reaches 0.35 kPa^(−1),which increased by 75%compared to the 0.2 kPa^(−1) of the pressure sensors without biomimetic structures.Moreover,the BPPS also achieves rapid response/recovery times(<90/15 ms).Our BPPS finds utility in tasks such as identifying objects of different weights,monitoring human respiratory status,and tracking motion,demonstrating its potential in wearable healthcare devices,assistive technology,and intelligent soft robotics.Moreover,it possesses the advantages of high sensitivity and fast response time in practical applications.展开更多
BACKGROUND Gastrointestinal endoscopy has been widely used in the diagnosis and treatment of gastrointestinal diseases.A great many of studies on gastrointestinal endoscopy have been done.AIM To analyze the characteri...BACKGROUND Gastrointestinal endoscopy has been widely used in the diagnosis and treatment of gastrointestinal diseases.A great many of studies on gastrointestinal endoscopy have been done.AIM To analyze the characteristics of top 100 cited articles on gastrointestinal endoscopy.METHODS A bibliometric analysis was conducted.The publications and their features were extracted from the Web of Science Core Collection,Science Citation Index-Expanded database.Excel,Web of Science database and SPSS software were used to perform the statistical description and analysis.VOSviewer software and Map-Chart were responsible for the visualizations.RESULTS The top 100 cited articles were published between 1976 and 2022.The guidelines(52%)and clinical trials(37%)are the main article types,and average publication year of the guidelines is much later than that of the clinical trials(2015 vs 1998).Among the clinical trials,diagnostic study(27.0%),cohort study(21.6%),case series(13.5%)and cross-sectional study(10.8%)account for a large proportion.Average citations of different study types and designs of the enrolled studies are of no significant differences.Most of the 100 articles were published by European authors and recorded by the endoscopic journals(65%).Top journals in medicine,such as the Lancet,New England Journal of Medicine and JAMA,also reported studies in this field.The hot spots of involved diseases include neoplasm or cancer-related diseases,inflammatory diseases,obstructive diseases,gastrointestinal hemorrhage and ulcer.Endoscopic surgery,endoscopic therapy and stent placement are frequently studied.CONCLUSION Our research contributes to delineating the field and identifying the characteristics of the most highly cited articles.It is noteworthy that there is a significantly smaller number of clinical trials included compared to guidelines,indicating potential areas for future high-quality clinical trials.展开更多
The success of robot-assisted pelvic fracture reduction surgery heavily relies on the accuracy of 3D/3D feature-based registration.This process involves extracting anatomical feature points from pre-operative 3D image...The success of robot-assisted pelvic fracture reduction surgery heavily relies on the accuracy of 3D/3D feature-based registration.This process involves extracting anatomical feature points from pre-operative 3D images which can be challenging because of the complex and variable structure of the pelvis.PointMLP_RegNet,a modified PointMLP,was introduced to address this issue.It retains the feature extraction module of PointMLP but replaces the classification layer with a regression layer to predict the coordinates of feature points instead of conducting regular classification.A flowchart for an automatic feature points extraction method was presented,and a series of experiments was conducted on a clinical pelvic dataset to confirm the accuracy and effectiveness of the method.PointMLP_RegNet extracted feature points more accurately,with 8 out of 10 points showing less than 4 mm errors and the remaining two less than 5 mm.Compared to PointNettt and PointNet,it exhibited higher accuracy,robustness and space efficiency.The proposed method will improve the accuracy of anatomical feature points extraction,enhance intra-operative registration precision and facilitate the widespread clinical application of robot-assisted pelvic fracture reduction.展开更多
基金financially supported by the Adisseo Innovation Research Center for Nutrition and Health(060–2222319005)Natural Science Foundation of Sichuan(2023NSFSC1135)National Natural Science Foundation of China(31972603)。
文摘Background Previous evidence suggests that methionine(Met)consumption can promote placental angiogenesis and improve fetal survival.To investigate the mechanisms by which increased levels of Met as hydroxyl-Met(OHMet)improve placental function,forty sows were divided into four groups and fed either a control diet,or diets supplemented with 0.15%OHMet,0.3%OHMet or 0.3%Met(n=10).Placentas were collected immediately after expulsion,and extracted proteins were analyzed by tandem mass tag based quantitative proteomic analysis.Results We found that 0.15%OHMet consumption significantly increased placental vascular density compared with the control.Proteomic analysis identified 5,136 proteins,87 of these were differentially expressed(P<0.05,|fold change|>1.2).Enriched pathways in the Kyoto Encyclopedia of Genes and Genomes for 0.15%OHMet vs.control and 0.15%OHMet vs.0.3%OHMet were glutathione metabolism;for 0.15%OHMet vs.0.3%Met,they were NOD-like receptor signaling and apoptosis.Further analysis revealed that 0.15%OHMet supplementation upregulated the protein expression of glutathione-S-transferase(GSTT1)in placentas and trophoblast cells compared with the control and 0.3%OHMet groups,upregulated thioredoxin(TXN)in placentas and trophoblast cells compared with the 0.3%OHMet and 0.3%Met groups,and decreased reactive oxygen species(ROS)levels in trophoblast cells compared with other groups.In contrast,sows fed 0.3%OHMet or 0.3%Met diets increased placental interleukin 1βlevels compared with the control,and upregulated the protein expression of complex I-B9(NDUFA3)compared with the 0.15%OHMet group.Furthermore,homocysteine,an intermediate in the trans-sulphuration pathway of Met,damaged placental function by inhibiting the protein expression of TXN,leading to apoptosis and ROS production.Conclusion Although dietary 0.15%OHMet supplementation improved placental angiogenesis and increased antioxidative capacity,0.3%OHMet or 0.3%Met supplementation impaired placental function by aggravating inflammation and oxidative stress,which is associated with cumulative homocysteine levels.
基金supported by the Guangdong Provincial Basic and Applied Basic Research Foundation(2021A1515010671,2020A1515011221)the Guangdong Provincial Key Discipline Research Capacity Enhancement Project(2021ZDJS071)the Guangdong Provincial College Innovation Project(2021KTSCX122,2022KQNCX077)。
文摘This study focuses on the impact of Gd^(3+),Sm^(3+),Er^(3+).Y^(3+),and Bi^(3+)multi-doping on the crystal structure,microscopic surface features,and ionic conductivity of cerium dioxide in the Ce_(1-x)(Gd_(1/5)Sm_(1/5)Er_(1/5)Y_(1/)_5Bi_(1/5))_(x)O_(2-δ)(GSEYB)system.This system holds promise as a solid electrolyte material for low and medium-temperature solid oxide fuel cells.The powders of Ce_(1-x)(Gd_(1/5)Sm_(1/5)Er_(1/5)Y_(1/5)Bi_(1/5))_(x)O_(2-δ)(x=0,0.10,0.15,0.20,0.25,0.30)were synthesized using the solid-phase reaction method.The GSEYB electrolytes were comprehensively investigated for their phase structure,microstructure,oxygen vacancy concentration,and ionic conductivity using X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),and impedance spectroscopy.XRD diffraction patterns confirm a cubic fluorite-type structure with Fm3m space groups in all multi-doped systems.After sintering at 1400℃for 10 h,the relative density of doped samples exceeds 96%.In terms of electrical properties,the Ce_(0.75)Gd_(0.05)Sm_(0.05)Er_(0.05)Y_(0.05)Bi_(0.05)O_(2-δ)(x=0.25)electrolyte exhibits the highest ionic conductivity(σ_(t)=4.45×10^(-2)S/cm)and the lowest activation energy(E_(a)=0.79 eV)at 800℃.The coefficient of thermal expansion of the developed electrolyte aligns well with that of the commonly used electrode materials.This compatibility positions it as a highly promising candidate for utilization as an electrolyte material in solid oxide fuel cells(SOFCs).
基金supported by the National Natural Science Foundation of China(Grant Nos.52272208,22309057)the Natural Science Foundation of Hubei Province(Grant No.2023AFB355)the Fundamental Research Funds for the Central Universities of China(Grant No.2662022LXQD001).
文摘Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C.
文摘BACKGROUND Cardiopulmonary bypass(CPB)is a life-support technology widely used in surgery.Review articles reflect research advances in a certain topic or field within a certain period of time.AIM To perform a bibliometric analysis of the review articles that focused on CPB for cardiovascular surgery.METHODS This study was based on a bibliometric analysis.Data were acquired from the Web of Science and basic bibliometric parameters were analyzed and visualized using VOSviewer and Excel.RESULTS We identified 141 review articles on CPB.Generally,the number of publications increased,and most of them were published in the 2010s(n=57,40.4%)and the 2020s(n=45,31.9%).There were 113(80.1%)narrative review articles,21(14.9%)meta-analysis studies and 7(5.0%)systematic review papers.The United States(n=25,17.7%)and China(n=21,14.9%)were the leading countries in terms of publication number.The articles were published in 98 different journals.The Journal of Cardiothoracic and Vascular Anesthesia(n=14,10.0%)and Perfusion-United Kingdom(n=11,7.8%)were preferred by the authors.The high-frequency keywords included inflammatory response,children,acute kidney injury,meta-analysis and off-pump,except for CPB and cardiac surgery.Inflammatory response had the closest relationship with CPB during cardiac surgery.The complications of CPB,including inflammatory response,kidney injury and ischemia,caught lots of concern.CONCLUSION The rapid increase of review papers shows that the research on CPB in cardiac surgery is increasingly being emphasized by scholars and clinical staff worldwide.Meta-analysis has been widely conducted to analyze clinical controversies and further guide clinical practice.Strategies to improving the outcomes of patients undergoing cardiac surgery with CPB are the hot spots in this field.
基金supported by the National Key Research and Development Program of China(2023YFB2805800 and 2021YFA1401003)the National Natural Science Foundation of China(62222513).
文摘Object imaging beyond the direct line of sight is significant for applications in robotic vision,remote sensing,autonomous driving,and many other areas.Reconstruction of a non-line-of-sight(NLOS)screen is a complex inverse problem that comes with ultrafast time-resolved imager requirements and substantial computational demands to extract information from the multi-bounce scattered light.Consequently,the echo signal always suffers from serious deterioration in both intensity and shape,leading to limited resolution and image contrast.Here,we propose a concept of vectorial digitelligent optics for high-resolution NLOS imaging to cancel the wall’s scattering and refocus the light onto hidden targets for enhanced echo.In this approach,the polarization and wavefront of the laser spot are intelligently optimized via a feedback algorithm to form a near-perfect focusing pattern through a random scattering wall.By raster scanning the focusing spot across the object’s surface within the optical-memory-effect range of the wall,we obtain nearly diffraction-limited NLOS imaging with an enhanced signal-to-noise ratio.Our experimental results demonstrate a resolution of 0.40 mm at a distance of 0.35 m,reaching the diffraction limit of the system.Furthermore,we demonstrate that the proposed method is feasible for various complex NLOS scenarios.Our methods may open an avenue for active imaging,communication,and laser wireless power transfer.
文摘BACKGROUND Stereoelectroencephalography(SEEG)is a minimally invasive preoperative evaluation of drug-resistant focal epilepsies.Increasing preclinical data show that SEEG has tremendous diagnostic and therapeutic value for epilepsy.There are currently many studies on SEEG.AIM To summarize the development and application of SEEG.METHODS We conducted a bibliometric analysis of research on SEEG from 2019 to 2023.We obtained publications on SEEG from the Web of Science Core Collection(WoSCC)database.Excel,VOSviewer,and CiteSpace were responsible for the analyses.A variety of bibliographic elements were collected,including annual publications,authors,countries/regions,journals,keywords,etc.RESULTS A total of 691 publications were included in this study.Professor Fabrice Bartolomei of Timone Hospital in France was the most productive and influential author in the field of SEEG,whereas the authors from the United States were the leaders in general.In addition,we found that deep learning and source localization in SEEG have been popular in recent years.CONCLUSION This study provides a comprehensive analysis of SEEG research and highlights the growing interest in SEEG and its deep learning and source localization.
基金supported by the National Key Research and Development Projects of China(Grant Nos.2023YFA1406103,2024YFA1611302,2024YFA1409200,and 2022YFA1403402)the National Natural Science Foundation of China(Grant Nos.12374142,12304170,12025408,12404179,and U23A6003)+2 种基金Beijing National Laboratory for Condensed Matter Physics(Grant No.2024BNLCMPKF005)the Chinese Academy of Sciences President’s International Fellowship Initiative(Grant No.2024PG0003)supported by the Synergetic Extreme Condition User Facility(SECUF,https://cstr.cn/31123.02.SECUF)。
文摘The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)transition occurring near the superconducting dome.Identifying the type of DW order is crucial for understanding the origin of superconductivity in this system.However,owing to the presence of La4Ni3O10 and other intergrowth phases in La_(3)Ni_(2)O_(7-δ)samples,extracting the intrinsic information from the La_(3)Ni_(2)O_(7) phase is challenging.In this study,we employed ^(139)La nuclear quadrupole resonance(NQR)measurements to eliminate the influence of other structural phases in the sample and obtain microscopic insights into the DW transition in La_(3)Ni_(2)O_(7-δ).Below the DW transition temperature T_(DW)∼153 K,we observe a distinct splitting in the±5/2↔±7/2 transition of the NQR resonance peak at the La(2)site,while only a line broadening is seen in the±3/2↔±5/2 transition peak.Through further analysis of the spectra,we show that the line splitting is due to a unidirectional charge modulation.A magnetic line broadening is also observed below T_(DW),accompanied by a large enhancement of the spin-lattice relaxation rate,indicating the formation of magnetically ordered moments in the DW state.Our results suggest a simultaneous formation of charge-and spin-density wave orders in La_(3)Ni_(2)O_(7-δ),thereby offering critical insights into the electronic correlations in Ni-based superconductors.
基金Project supported by the Key Research and Development Program of Heilongjiang (2022ZX01A01)National Natural Science Foundation of China (51975167)Natural Science Foundation of Heilongjiang Province(LH2022E080)
文摘The anisotropy and tension-compression asymmetry of rare-earth magnesium(Mg-RE) alloys have attracted significant attention.In this study,the room-temperature tensile anisotropy and tensioncompression asymmetry of the extruded Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy were investigated utilizing techniques such as optical microscopy(OM),electron backscatter diffraction(EBSD),and viscoplastic self-consistent(VPSC) modeling.Among the tensile samples,the TO sample(with axis parallel to extrusion direction) exhibits the greatest tensile yield strength(TYS) of 270 MPa and ultimate tensile strength(UTS) of 336 MPa,the T45 sample(with axis inclined at a 45° angle to extrusion direction) and T90 sample(with axis perpendicular to extrusion direction) exhibit lower TYS and UTS.The CO sample shows a slightly greater compressive yield strength(CYS) of 290 MPa.The ratio of TYS/CYS is approximately 1.07.This study significantly adjusts the VPSC hardening parameters through the Schmid factor of deformation mechanisms in Mg-RE alloy,particularly increasing the τ0(critical resolved shear stress,CRSS) and τ1values for basalslip and {10-12} twinning.The ratios of CRSS for other deformation mechanisms to basalslip are approximately as follows:CRSSTwin/CRSSBas=2,CRSSpri/CRSSBas≈2.7and CRSSPyr/CRSSBas≈3.3,while these ratios in traditional alloys are generally higher.The stress-strain curves and pole figures obtained from the modified VPSC model demonstrate excellent agreement with experimental results.According to the VPSC simulation results,the primary factor contributing to tensile anisotropy is the disparity in the activation levels of slip systems.The inclusion of rare-earth elements mitigates the tension-compression asymmetry by reducing the difference of CRSS between different deformation mechanisms.
基金financial support provided by Key Research and Development Program of Heilongjiang(Grant No.2022ZX01A01)Natural Science Found of Heilongjiang Province(LH2022E080)。
文摘The tension-compression asymmetry presents notable challenges for the application of magnesium alloys in many fields.In this study,the solid-solution treated Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy's tension-compression asymmetry was examined using optical microscope(OM),x-ray diffraction(XRD),viscoplastic self-consistent(VPSC)modeling,and electron backscatter diffraction(EBSD).The VPSC hardening parameters were significantly adjusted based on the Schmid factor of deformation modes in rare earth magnesium(Mg-RE)alloy,which came from the EBSD data.Excellent agreement was found between the modified VPSC model's calculation results,especially the stress-strain curves and pole figures.The alloy exhibited good strength with a negligible tension-compression asymmetry and an impressive 0.98 ratio of compressive yield strength to tensile yield strength(CYS/TYS).The main cause could be attributed to the unusual texture of(11-20)<0001>in alloy,which eliminated the imbalance in tension and compression deformation by having a negative effect on the activation of{10-12}twinning in tensile and a positive effect in compressive deformation.The activation level of{10-12}twinning was 0.37 and 0.40calculated by VPSC model,in the plastic deformation of tension and compression,respectively;in the tensile and compression samples,the EBSD data indicated that approximately 31.9%and 31.1%(area proportion)of the grains were deformed with twins,respectively.Both tension and compression deformation showed the{10-12}twinning in the early stage of deformation,which transformed to{11-22}twinning in the later stage.The considerable activation of pyramidal during the later stages of deformation endowed the alloy with good ductility.
文摘As smart contracts,represented by Solidity,become deeply integrated into the manufacturing industry,blockchain-based Digital Twins(DT)has gained momentum in recent years.Most of the blockchain infrastructures in widespread use today are based on the Proof-of-Work(PoW)mechanism,and the process of creating blocks is known as“mining”.Mining becomes increasingly difficult as the blockchain grows in size and the number of on-chain business systems increases.To lower the threshold of participation in the mining process,“mining pools”have been created.Miners can cooperate and share the mining rewards according to the hashrate they contributed to the pool.Stratum is the most widely used communication protocol between miners and mining pools.Its security is essential for the participants.In this paper,we propose two novel Man-In-The-Middle(MITM)attack schemes against Stratum,which allow attackers to steal miners'hashrate to any mining pool using hijacked TCP connections.Compared with existing attacks,our work is more secretive,more suitable for the real-world environment,and more harmful.The Proof-of-Concept(PoC)shows that our schemes work perfectly on most mining softwares and pools.Furthermore,we present a lightweight AI-driven approach based on protocol-level feature analysis to detect Stratum MITM for blockchain-based DTs.Its detection model consists of three layers:feature extraction layer,vectorization layer,and detection layer.Experiments prove that our detection approach can effectively detect Stratum MITM traffic with 98%accuracy.Our work alerts the communities and provides possible mitigation against these more hidden and profitable attack schemes.
基金the generous financial support provided by Sichuan Science and Technology Program(2024ZDZX0030)Chengdu Science and Technology Program(2024-JB00-00010-GX)。
文摘During the crystallization of perovskite films,defects at Pb and I sites are generated,causing lattice mismatch and adversely affecting the performance of perovskite solar cells(PSCs).Herein,we introduced aπ-conjugated molecule with a dual-ring structure,namely CCA(3,4-ethylenedioxythiophene-2,5-dicarboxylic acid),as an additive to regulate the crystallization of perovskite films and passivate defects.As a bidentate Lewis base,CCA coordinates the bidentate carboxyl groups with free Pb^(2+)through the delocalized electrons of its conjugated ring.This coordination regulates lattice stress,repairs the 3D[PbI6]octahedra,stabilizes the perovskite framework,and guides the vertical orientation growth of grains.Simultaneously,the addition of CCA shifts the perovskite’s band structure towards p-type,achieving better energy-level alignment with the doped hole-transport layer(HTL)and suppressing non-radiative recombination.Consequently,the prepared CCA-doped single-junction devices exhibit an outstanding power conversion efficiency(PCE)of 24.90%,with a high open-circuit voltage(VOC)of 1.195,a high fill factor(FF)of 84.60%,and low FF loss.The optimized films and devices show enhanced long-term stability,retaining 80.1%of the initial efficiency after continuous illumination for 560 h.Additionally,a PCE of 21.6%was achieved in devices with a bandgap of 1.68 eV,which were further extended to perovskite/silicon tandem devices,achieving high-performance devices with PCEs of 30.96%(aperture area:1.05 cm^(2))and 25.96%(aperture area:20.06 cm^(2)).
基金supported by the National Natural Science Foundation of China(Project Approval Number:52404270)Postdoctoral Innovative Talent Support Program(BX20230427)+2 种基金Postdoctoral Surface Fund Grants(2023M743874)Research Start-up Fund of China University of Petroleum(Beijing)(2462023XKBH017)Fundamental Research Project Grant of China Academy of Safety Science and Technology(2023JBKY07)。
文摘Gas explosions are a frequent hazard in underground confined spaces in the process of urban development.Liquid sedimentary layers,commonly present in these environments,have not been sufficiently studied in terms of their impact on explosion dynamics.This study aims to investigate how gas-liquid two-phase environments in confined underground spaces affect the explosion characteristics of natural gas.To achieve this,experiments are conducted to examine the propagation of natural gas explosions in water and diesel layers,focusing on the influence of liquid properties and the liquid fullness degree(Lx)on explosion behavior.The results indicate that the presence of a liquid layer after the initial ignition stage significantly attenuates both the peak overpressure and the rise speed of pressure,in comparison to the natural gas conditions.During the subsequent explosive reaction,the evaporation and combustion of the diesel surface resulted in a distinct double-peak pressure rise profile in the diesel layer,with the second peak notably exceeding the first peak.Under conditions with a liquid sedimentary layer,the flame propagation velocities range from 6.53 to 34.1 m/s,while the overpressure peaks vary between 0.157 and 0.255 MPa.The explosion duration in both the water and diesel layer environments is approximately twice as long as that of the natural gas explosion,although the underlying mechanisms differ.In the diesel layer,the prolonged explosion time is attributed to the evaporation and combustion of the diesel,while in the water layer,the flame propagation velocity is significantly reduced.Under the experimental conditions,the maximum explosion energy reached 7.15×10~6J,corresponding to a TNT equivalent of 1.7.The peak overpressure surpassed the threshold for human fatality as defined by overpressure standards,posing a potential risk of damage to large steel-frame structures.The explosion shockwave in diesel layer conditions(L_(d)=0%,5%,7.5%,12.5%)and water layer(L_(w)=12.5%)conditions is observed to be sufficient to damage earthquake-resistant reinforced concrete.This study investigates the impact of sediment layer thickness and composition on gas explosions,and evaluates the associated explosion energy to assess human injuries and structural damage in underground environments.The findings of this study provide a scientific reference for urban underground safety.
基金supported by the National Natural Science Foundation of China(Grant 32027802)the Key R&D Program of Zhejiang(Grant 2022C03071)the Fundamental Research Funds for the Central Universities(Grant 226‐2024‐00059).
文摘Background:Vascular thrombus is a common complication in cancer patients and can be classified as benign or neoplastic based on tumor cell presence.Conventional imaging modalities provide anatomical information but exhibit limited specificity in distinguishing neoplastic from benign thrombi,prompting the evaluation of 2‐deoxy‐2‐[^(18)F]fluoro‐D‐glucose positron emission tomography/computed tomography([^(18)F]FDG PET/CT),which leverages metabolic differences for improved differentiation.In this study,the efficacy of[^(18)F]FDG PET/CT for differentiating neoplastic thrombus from benign thrombus was evaluated in patients with malignant tumors.Methods:Sixty‐five patients with histologically or clinically confirmed neoplastic or benign thrombus who underwent[^(18)F]FDG PET/CT were retrospectively enrolled.Both visual and semi‐quantitative analyses of the PET/CT scans were conducted.The difference in maximum standardized uptake value(SUVmax)between neoplastic and benign thrombus was assessed using a t‐test.Furthermore,receiver operating characteristics(ROC)analysis was performed to determine the optimal SUVmax threshold for differentiating neoplastic from benign thrombus.Results:Within the cohort,55 patients were diagnosed with neoplastic thrombus and 10 patients with benign thrombus.In the visual analysis,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy of[^(18)F]FDG PET/CT for diagnosing neoplastic thrombus were 96.4%,90.0%,98.1%,81.8%,and 95.4%,respectively.In the semiquantitative analysis,the sensitivity,specificity,positive predictive value,negative predictive value,and diagnostic accuracy for diagnosing neoplastic thrombus were 96.4%,100%,100%,83.3%,and 96.9%,respectively.The normalized SUVmax of neoplastic thrombus was significantly higher than that of benign thrombus(10.11�5.32 vs.2.21�0.51,p<0.001).The area under the ROC curves for visual assessment and semi‐quantitative analysis were 0.932 and 0.993,respectively.There was no statistically significant difference observed between these two assessment methods(p=0.317).Conclusions:[^(18)F]FDG PET/CT is capable of differentiating neoplastic thrombus from benign thrombus.Both visual and semiquantitative analyses demonstrated high diagnostic sensitivity,specificity,and accuracy.
基金The National Natural Science Foundation of China under contract Nos 42330810 and U19B6003-01the China National Petroleum Corporation Science Research and Technology Development Project under contract Nos 2021DJ1501 and 2024DQ03016.
文摘The dominant lithofacies of reservoirs in the Barra Velha formation of the study area are grainstones,which exhibit strong heterogeneity,and the seismic responses of buildups are characterized by low relief,posing a substantial challenge in evaluating the factors controlling high-quality reservoir development.This study thoroughly investigated sedimentary facies and diagenetic processes based on petrological and geophysical data,and a semi-open-rimmed carbonate platform model was established to illustrate the lithofacies distribution pattern.Additionally,the diagenetic processes and their main controlling factors were analyzed,and an attempt was made to establish a diagenetic sequence.Our findings indicate that sedimentary processes control the distribution of lithofacies,while diagenesis ultimately determines the petrophysical properties.The lithofacies types are closely associated with depositional environments.Shrub-like stromatolites are more developed at the bench margin and inner slope,while spherulites occur preferentially in the bench interior and mid-slope environments.Laminites accumulate in profundal or bench interior facies,whereas grainstones are present across all depositional environments,although their components vary.Integrated seismic attributes revealed that the bench margin exhibits nearly circular features,representing favorable conditions for high-quality reservoir development.The primary diagenetic processes in the study area include meteoric diagenesis,chemical compaction,and possible hydrothermal activity.During the eodiagenetic phase,the dissolution of Mg-clays played a key role in the diagenesis of carbonate rocks in the Barra Velha formation.This process typically occurred at structural highs,where Mg-clays were replaced by calcite spherulites,silicates,and dolomite.Some grainstones developed dolomite rims around particles,enhancing their resistance to compaction and preserving primary porosity.In the mesodiagenetic phase,chemical compaction and hydrothermal activity often caused primary pores to be filled with mosaic or blocky calcite and macrocrystalline quartz,leading to reduced permeability and porosity.Although dissolution was common in the study area,its impact on increasing pore space was limited.This study aims to improve drilling success rates in high-quality reservoirs and enhance hydrocarbon discoveries in the study area while also contributing to a better understanding of the evolution and distribution of high-quality reservoirs in analogous lacustrine carbonate settings.
基金supported by the National Natural Science Foundation of China(Grant Nos.52378321 and 52079003).
文摘Based on the energy dissipation caused by consolidation deformation of the porous media under external force and migration of the internal suspended substances,a coupled multiphase-substance flow(CMF)model was established.This model introduced the new concepts,such as particle temperature and particle entropy,to describe energy dissipation at meso-level.This model used a potential energy density function and migration coefficients to establish the corresponding connection between the dissipative force and dissipative flow.This viewpoint unifies the deformation,seepage,and suspended substance migration of geotechnical materials under the framework of granular thermodynamics.It can reflect the evolution of effective stress in the solid matrix of multi-components in a particle-reorganized state,and considers the temperature driving effect.The proposed CMF model is validated using the experimental results under coupled migration of heavy metal ions(HMs)and suspended particles(SPs).The calculation results demonstrated that the CMF model can describe the flow process under the conditions of arbitrary changes in different suspended substance types,injection concentrations,and injection velocities.
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.52021003)National Natural Science Foundation of China(Nos.52222509,52105301)+1 种基金the Natural Science Foundation of Jilin Province(Grant No.20220101220JC)supported by“Fundamental Research Funds for the Central Universities”.
文摘Flexible piezoresistive pressure sensors have attracted much attention for applications in health monitoring and human-machine interfaces due to their simple device structures and easy-to-read signals.For practical applications,the deployment of flexible pressure sensors characterized by high sensitivity and fast response time is imperative for the rapid and accurate detection and monitoring of tiny signals.Such capabilities are essential for facilitating immediate feedback and informed decision-making across a spectrum of contexts.Drawing lessons from the hypersensitive and fast-responding pressure sensing structures in the dragonfly’s neck(for stable imaging during its highly maneuverable flight),a Biomimetic Piezoresistive Pressure Sensor(BPPS)with exquisite mechanically interlocking sensing microstructures is developed.Each interlocking perceptual structure pair consists of an ox-horn-shaped and a mushroom-shaped structural unit.Through the characteristic configuration of the perceptual structure pair,the BPPS realizes a fast gradient accumulation of the contact area,thus synergistically enhancing the sensitivity and fast response capability.Remarkably,the sensitivity of the BPPS reaches 0.35 kPa^(−1),which increased by 75%compared to the 0.2 kPa^(−1) of the pressure sensors without biomimetic structures.Moreover,the BPPS also achieves rapid response/recovery times(<90/15 ms).Our BPPS finds utility in tasks such as identifying objects of different weights,monitoring human respiratory status,and tracking motion,demonstrating its potential in wearable healthcare devices,assistive technology,and intelligent soft robotics.Moreover,it possesses the advantages of high sensitivity and fast response time in practical applications.
文摘BACKGROUND Gastrointestinal endoscopy has been widely used in the diagnosis and treatment of gastrointestinal diseases.A great many of studies on gastrointestinal endoscopy have been done.AIM To analyze the characteristics of top 100 cited articles on gastrointestinal endoscopy.METHODS A bibliometric analysis was conducted.The publications and their features were extracted from the Web of Science Core Collection,Science Citation Index-Expanded database.Excel,Web of Science database and SPSS software were used to perform the statistical description and analysis.VOSviewer software and Map-Chart were responsible for the visualizations.RESULTS The top 100 cited articles were published between 1976 and 2022.The guidelines(52%)and clinical trials(37%)are the main article types,and average publication year of the guidelines is much later than that of the clinical trials(2015 vs 1998).Among the clinical trials,diagnostic study(27.0%),cohort study(21.6%),case series(13.5%)and cross-sectional study(10.8%)account for a large proportion.Average citations of different study types and designs of the enrolled studies are of no significant differences.Most of the 100 articles were published by European authors and recorded by the endoscopic journals(65%).Top journals in medicine,such as the Lancet,New England Journal of Medicine and JAMA,also reported studies in this field.The hot spots of involved diseases include neoplasm or cancer-related diseases,inflammatory diseases,obstructive diseases,gastrointestinal hemorrhage and ulcer.Endoscopic surgery,endoscopic therapy and stent placement are frequently studied.CONCLUSION Our research contributes to delineating the field and identifying the characteristics of the most highly cited articles.It is noteworthy that there is a significantly smaller number of clinical trials included compared to guidelines,indicating potential areas for future high-quality clinical trials.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFB1313800)the National Science Foundation of China(Grant No.NSFC62373259)+1 种基金the Natural Science Foundation of Top Talent of SZTU(Grant No.GDRC202303)the Education Promotion Foundation of Guangdong Province(Grant No.2022ZDJS115).
文摘The success of robot-assisted pelvic fracture reduction surgery heavily relies on the accuracy of 3D/3D feature-based registration.This process involves extracting anatomical feature points from pre-operative 3D images which can be challenging because of the complex and variable structure of the pelvis.PointMLP_RegNet,a modified PointMLP,was introduced to address this issue.It retains the feature extraction module of PointMLP but replaces the classification layer with a regression layer to predict the coordinates of feature points instead of conducting regular classification.A flowchart for an automatic feature points extraction method was presented,and a series of experiments was conducted on a clinical pelvic dataset to confirm the accuracy and effectiveness of the method.PointMLP_RegNet extracted feature points more accurately,with 8 out of 10 points showing less than 4 mm errors and the remaining two less than 5 mm.Compared to PointNettt and PointNet,it exhibited higher accuracy,robustness and space efficiency.The proposed method will improve the accuracy of anatomical feature points extraction,enhance intra-operative registration precision and facilitate the widespread clinical application of robot-assisted pelvic fracture reduction.
