One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effect...One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effective alternative to significantly reduce these emissions.In this study,rapeseed methyl ester(RME)was used as a diesel engine fuel and the emitted particulate matter was comparedwith ultra-lowsulfur diesel(ULSD).Inmost experimental studies,the emission of soot wasmeasured.In this work,the effects of injection timing,injection pressure(IP),and engine load on fine particulate matter in both nucleation and accumulation modes were studied.The results show that IP increases the number of particles in the accumulation mode while the number of particles in the crystallization mode is higher for rapeseed methyl ester(RME)than for ultra-low sulfur diesel(ULSD).Conversely,the formation rates of particles in the accumulationmode are higher for ULSD.Cumulative concentration numbers(CCN)are generally higher for RME in crystallization mode but higher for ULSD in accumulation mode.Increasing the IP reduces the CCN values.The particle size in crystallizationmode reaches a maximum of 22 nm at IPs of 800 and 1000 bar but decreases to 15 nm at 1200 bar.Most fine particles fall in the 5–100 nm diameter range.High engine loads reduce the particle size distribution in nucleationmode for both fuels,with a slight increase in particle size in nucleationmode.Thestudy concluded that the use of rapeseed methyl ester as an engine fuel benefits the environment and improves air quality due to the significant reduction in the size,number,and concentration of nano-soot particles and total particles emitted from the engine.展开更多
Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attrac...Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attracted much attention^([1−3]).In 2023,Kyoto University reported GaAs-based 945 nm PCSELs with a continuous-wave(CW)single-mode output power of exceeding 50 W,and a narrow beam divergence angle of 0.05°,demonstrating a brightness of 1 GW·cm^(−2)·sr^(−1),which rivals those of the existing bulky lasers^([4]).展开更多
Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propo...Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propofol injection pain(PIP) is well-known in the operating room and is commonly countered by the prophylactic administration of lidocaine.In anesthesia,PIP is encountered in 28%–90% of patients.^([4,5]) However,PIPprophylaxis does not seem to be efficacious in every population.^([6,7]) Whether procedural sedation and analgesia(PSA) in the emergency department(ED) warrants lidocaine administration is unclear.展开更多
Myocardial infarction (MI) continues to be the primary cause of death globally. Oxidative stress in the initial phase of MI, followed by uncontrolled and excessive myocardial fibrosis, significantly impedes cardiac re...Myocardial infarction (MI) continues to be the primary cause of death globally. Oxidative stress in the initial phase of MI, followed by uncontrolled and excessive myocardial fibrosis, significantly impedes cardiac repair efficiency post-MI, culminating in adverse ventricular remodeling and potential heart failure. To address the diverse pathological stages of MI, an injectable composite hydrogel containing versatile nanoparticles was developed. In this study, mesoporous silicon nanoparticles (MSNs) served as carriers for encapsulating microRNA-29b (miR-29b) mimics with antifibrotic activity, subsequently coated with a complex of natural antioxidant tannic acid and zinc ions (TA/Zn). These nanoparticles were then embedded into a biocompatible alginate hydrogel to enhance retention within the infarcted myocardium. Upon injection into the infarcted region of MI mice, the composite hydrogel gradually released the nanoparticles as it degraded. Initially, the TA/Zn complex on the outer layer scavenged reactive oxygen species, thereby inhibiting cell apoptosis. The subsequent dissociation of the TA/Zn complex led to the release of the encapsulated miR-29b mimics that could inhibit the activation of cardiac fibroblasts and collagen production, thereby alleviating fibrosis progression. Overall, this composite hydrogel demonstrated the potential to reduce infarct size and improve cardiac function, suggesting its promise as a synergistic therapeutic approach for repairing infarcted myocardium.展开更多
Following high-level diplomacy,a recent forum has bridged China and Spanish-and Portuguese-speaking countries by injecting substance into cooperation frameworks through a new education alliance and concrete projects.
This paper investigates the application of Direct Current Atmospheric Plasma Spraying(DC-APS)as a versatile thermal spray technique for the application of coatings with tailored properties to various substrates.The pr...This paper investigates the application of Direct Current Atmospheric Plasma Spraying(DC-APS)as a versatile thermal spray technique for the application of coatings with tailored properties to various substrates.The process uses a high-speed,high-temperature plasma jet to melt and propel the feedstock powder particles,making it particularly useful for improving the performance and durability of components in renewable energy systems such as solar cells,wind turbines,and fuel cells.The integration of nanostructured alumina(Al_(2)O_(3))thin films into multilayer coatings is considered a promising advancement that improves mechanical strength,thermal stability,and environmental resistance.The study highlights the importance of understanding injection parameters and their impact on coating properties and uses simulation tools such as the Jets&Poudres(JP)code for in-depth analysis.Furthermore,the paper discusses the implementation of Artificial Neural Networks(ANN)to optimize the coating process by predicting flight characteristics and improving operating conditions.The results show that ANN models are effective in achieving highly accurate prediction values,highlighting the potential of AI in improving thermal spray technology.展开更多
Nonobstructive azoospermia(NOA)is the most challenging and complex clinical scenario for infertile men.Besides circumstances such as hypogonadotropic hypogonadism,surgical sperm retrieval is typically necessary,and mi...Nonobstructive azoospermia(NOA)is the most challenging and complex clinical scenario for infertile men.Besides circumstances such as hypogonadotropic hypogonadism,surgical sperm retrieval is typically necessary,and microdissection testicular sperm extraction(micro-TESE)is the procedure of choice for men with NOA desiring to father children with their own gametes.Micro-TESE results in the highest numbers of sperm cells retrieved for use with in vitro fertilization/intracytoplasmic sperm injection(ICSI)in comparison to all other techniques for surgical sperm retrieval in men with NOA.Several factors may affect sperm retrieval rate and ICSI outcomes,including the patient’s age,testicular volume,histopathological and genetic profile,and serum hormone levels.This article aims to review the medical literature describing predictors of successful micro-TESE and the outcomes of ICSI in men with NOA.展开更多
The evolution of stresses due to inhomogeneity in metal injection molding （MIM） parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on th...The evolution of stresses due to inhomogeneity in metal injection molding （MIM） parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on the continuum mechanics and thermal elasto-viseoplastic constitutive law. Model parameters were identified from the dilatometer sintering experiment. The real density distribution of green body was measured by X-ray computed tomography （CT）, which was regarded as the initial condition of sintering model. Numerical calculation of the above sintering model was carried out with the finite element soRware Abaqus, through the user-defined material mechanical behavior （UMAT）. The calculation results showed that shrinkages of low density regions were faster than those of high density regions during sintering, which led to internal stresses. Compressive stresses existed in high density regions and tensile stresses existed in low density regions. The densification of local regions depended on not only the initial density, but also the evolution of stresses during the sintering stage.展开更多
With its growth in spacecraft control applications,the microcontroller(MCU)becomes increasingly sensitive to radiation and the risks of system failure.In a radiation environment,the MCU is vulnerable to impacts from h...With its growth in spacecraft control applications,the microcontroller(MCU)becomes increasingly sensitive to radiation and the risks of system failure.In a radiation environment,the MCU is vulnerable to impacts from high-energy particles,which can lead to single-event effect(SEE)that disrupt normal system operations.The pipeline of MCU,being the core structure of the system,is particularly susceptible to single-event upset(SEU)and potentially causes execution failures.However,existing radiation-hardening techniques offer limited effectiveness for pipelines.To enhance SEU resistance,this study focused on a 32-bit MCU core with eight pipeline stages,proposing a pipeline hardening approach that utilizes lockstep technology to improve fault tolerance.Signals from two processors were compared including register write data,register contents and pre-fetched instructions.Any discrepancies triggered error flags to indicate faults.When an error flag was raised,recovery was initiated through an interrupt.The interrupt handler then retrieved state information from the advanced peripheral bus(APB)slave module to restore the CPU's operational state and resume execution.By combining hardware-based state preservation with software-driven error recovery,the proposed solution demonstrated significant improvements in fault tolerance rates and performance compared to traditional checkpoint-based techniques.After completing the pipeline hardening design,a fault injection platform was utilized in this paper to simulate real-world error conditions on internal processor modules.The platform was developed based on the circuit's register-transfer-level(RTL)design and statistical results.The fault injection platform was performed by automatically finding all registers within the target design.The register values were forced to upset at the tens of nanoseconds scale in the RTL description of the circuit's design.After running the circuit's functional simulation,the statistics of the faults in registers were displayed on the platform,which evaluated the influence of SEU.The vulnerability of SEU in the circuit could be observed from the results of the soft error statistics.The post-hardening soft error rates were then measured and compared to pre-hardening data,providing a quantitative evaluation of the improvements.Using this method,the soft error rates of the modules in the MCU core such as PFU,DPU,and Cache AXIM are 40.07%,26.36%,and 27.29%respectively before hardening.The soft error rates of modules mentioned above are reduced to 0%,0.69%,and 1.11%after hardening.The hardened and non-hardened designs of the entire core were implemented in FPGA.The total resource utilization of the triple mode redundancy(TMR)is 111984,as indicated by the number of look-up tables(LUTs)and registers consumed in the FPGA.The total resource utilization of this work is 78034,and the ratio of resource utilization between this work and TMR is approximately 69.68%.The error recovery time for the hardened MCU processor was analyzed using the completion cycles of a bubble sort algorithm as a benchmark.In this paper,the average recovery cycle using the software checkpoint roll-back method is 36479.06,and the average recovery cycle using this work is 26922.5.The ratio of recovery cycles between this work and checkpoint roll-back is about 73.8%.Assessments through random fault injection and FPGA implementation indicate that this approach effectively reduces processor faults caused by soft errors while optimizing resource utilization and efficiency over triplemodular redundancy.展开更多
Early knee osteoarthritis(KOA)is characterized by progressive degeneration of the articular cartilage,synovial inflammation,and excessive accumulation of reactive oxygen species(ROS).At present,intra-articular injecti...Early knee osteoarthritis(KOA)is characterized by progressive degeneration of the articular cartilage,synovial inflammation,and excessive accumulation of reactive oxygen species(ROS).At present,intra-articular injection of hyaluronic acid(HA)is widely used to alleviate symptoms;however,its lubrication persistence,antioxidant,and anti-inflammatory abilities are limited,and it is difficult to effectively delay the early process of cartilage degeneration.Based on this,hyaluronic acid-g-lipoic acid(HA-LA)was synthesized by esterification reaction,and HA-LA microspheres were prepared by a reversed-phase emulsion method,which was combined with a macromolecular HA-LA solution to form injectable hydrogels.The objective of this study was to evaluate the efficacy of an injectable hydrogel based on hyaluronic acid-g-lipoic acid microspheres(HA-LA MS)for the treatment of KOA and to verify its injectability,lubricity,reactive oxygen species(ROS)scavenging ability,and anti-inflammatory effects.The results show that the HA-LA MS hydrogel has excellent shear thinning characteristics and continuous injectability,and its microsphere structure significantly reduces the interfacial friction coefficient through the rolling effect.In vitro experiments have shown that the hydrogel can efficiently scavenge ROS,reduce the expression of inflammatory factors,and is non-cytotoxic.The HA-LA MS injectable hydrogel has excellent lubricity,ROS scavenging ability,and anti-inflammatory effects in vivo,which can effectively delay the degeneration of early KOA cartilage,and its efficacy is significantly better than that of traditional hyaluronic acid,making it a promising intra-articular injection preparation.展开更多
BACKGROUND The previous studies have primarily focused on the influence of botulinum toxin A(BoNT-A)injection on emotions during the period of peak motor symptom improvement in blepharospasm patients,based on facial f...BACKGROUND The previous studies have primarily focused on the influence of botulinum toxin A(BoNT-A)injection on emotions during the period of peak motor symptom improvement in blepharospasm patients,based on facial feedback hypothesis.AIM To evaluate the sustained anxiolytic and antidepressant effects of BoNT-A in blepharospasm patients beyond motor symptom control.METHODS We recruited benign essential blepharospasm patients with BoNT-A treatment and collected their data to compare scale scores of Jankovic Rating Scale,Blepharospasm Disability Index,Self-rating Anxiety Scale(SAS),Self-rating Depression Scale(SDS),Hamilton Anxiety Scale and Hamilton Depression Scale between pretreatment(baseline)and pre-reinjection(treatment),to further assess the effects of repeated treatments with BoNT by using sub-group analyses in the certain special states.RESULTS A total of 21 eligible blepharospasm patients were with the mean age of 58.4 years and a male-to-female ratio of 1:6.Significantly decreases in the subscale scores of SDS and SAS,including SDS well-being index,decreased capacity and hard to decide,SAS inability to sit still and headache were showed at post-a single BoNT-A injection when scale scores of Jankovic Rating Scale and Blepharospasm Disability Index were matched between baseline and posttreatment.With each additional BoNT-A injection,the odds ratio of patients with the moderate depressive symptoms decreased by 92.6%.Moreover,BoNT treatment remained a decrease in the subscale scores of SDS and SAS in patients with repeated injections.CONCLUSION This study is to demonstrate that repeated BoNT-A injection have a long-lasting relief for anxiety and depressive symptoms in blepharospasm even after its motor symptom-modulating effects have diminished.展开更多
Objective:To compare the clinical efficacy and safety of intravitreal injection of faricimab and conbercept in the treatment of diabetic macular edema(DME).Methods:A total of 50 patients diagnosed with DME in our hosp...Objective:To compare the clinical efficacy and safety of intravitreal injection of faricimab and conbercept in the treatment of diabetic macular edema(DME).Methods:A total of 50 patients diagnosed with DME in our hospital from January 2023 to May 2025 were selected and randomly divided into an observation group and a control group,with 25 cases in each group,using a random number table method.The observation group received intravitreal injection of faricimab,while the control group received intravitreal injection of conbercept.Both groups adopted a loading phase plus maintenance phase treatment regimen.The best-corrected visual acuity(BCVA,expressed in logMAR)and central subfield thickness(CST)of the two groups were compared before treatment and at 1,3,and 6 months after treatment,and the incidence of adverse events during treatment was recorded.Results:The logMAR BCVA in the observation group was lower than that in the control group at 3 and 6 months after treatment(both p<0.05).The CST in the observation group was smaller than that in the control group at 1,3,and 6 months after treatment(all p<0.05).There was no statistically significant difference in the overall incidence of adverse events between the two groups(χ^(2)=0.189,p=0.663).Conclusion:Both intravitreal injections of faricimab and conbercept are effective in improving visual acuity and reducing macular edema in patients with DME,with good safety profiles.However,faricimab demonstrates superior efficacy in the medium to long term(3 and 6 months)compared to conbercept,making it more suitable for long-term treatment of patients with DME.展开更多
Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Althou...Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Although these procedures are now performed in more controlled and medically supervised environments,their long-term outcomes remain poorly understood.The promotion of such medical treatments contributes to an increasing interest among adult males in self-injection as a method to alleviate psychological distress associated with penile size concerns.At the same time,access to injectable substances through unofficial or unregulated sources has become increasingly easy.Tor our knowledge,we report the first documented case of self-injection with Garamycin®(gentamicin)cream,contributing to the literature on the often multidisciplinary management of penile enlargement injections,a field still lacking well-established guidelines.Case Description:This case report describes a young patient who self-injected Garamycin®into the penis for the purpose of enlargement.He presented to our urology department with worsening symptoms,including severe and poorly tolerated pain.His primary request was prompt relief of pain while preserving,as much as possible,the aesthetic appearance and functional integrity of his penis.This case required a multi-stage surgical approach to salvage the penis and preserve both its structural integrity and functional outcome.Conclusions:To our knowledge,this case report documents the first reported instance of Garamycin®injection performed for the purpose of penile enlargement.It provides insight into the clinical course of such penile cream injections,demonstrates that a two-stage scrotal flap can achieve both functional and aesthetic outcomes,and highlights the importance of comprehensive management particularly addressing the traumatic impact of penile deformity secondary to inflammation and/or infection,as well as the body dysmorphic concerns often associated with these cases.展开更多
The Southern Advanced Photon Source(SAPS)is a diffraction-limited synchrotron light source under design,which employs longitudinal injection as its primary injection scheme.This kind of injection scheme requires that ...The Southern Advanced Photon Source(SAPS)is a diffraction-limited synchrotron light source under design,which employs longitudinal injection as its primary injection scheme.This kind of injection scheme requires that the injected beam has a short bunch length and low emittance,and the preferred injector should offer high stability and low cost.Therefore,an injector based on a booster synchrotron was developed.The proposed injector includes a 250 MeV linac,a booster synchrotron that ramps the beam energy to 3.5 GeV,and two beam transport lines to ensure efficient beam delivery and beam quality preservation.The linac utilizes a thermionic high-voltage DC gun for reliable operation and features a bunching system with an advanced focusing system to preserve the emittance.To meet the injection requirements of the SAPS,a comprehensive design for the booster has been conducted.The booster synchrotron employs a threefold lattice structure,incorporating modified theoretical minimum emittance cells with a small momentum compaction factor and a high voltage to achieve an emittance of 3.98 nm rad and a bunch length of 4.8 mm.The injector has the potential to deliver a high charge,reducing the injection period of the storage ring to less than 1 min.Simulations demonstrated the expected performance,with a transmission efficiency of 90%,confirming its capability to meet the injection requirement of the SAPS storage ring.This design offers a stable and efficient solution for the SAPS.展开更多
BACKGROUND Coronary microembolization(CME)is the major leading cause of perioperative myocardial injury during coronary revascularization.Semaglutide exerts multiple protective biological activities,but its cardioprot...BACKGROUND Coronary microembolization(CME)is the major leading cause of perioperative myocardial injury during coronary revascularization.Semaglutide exerts multiple protective biological activities,but its cardioprotective effects on CME remain unclear.Thus,this experiment studied the impact of semaglutide on CME-induced myocardial injury.METHODS A rat CME model was generated by injecting microspheres into the left ventricle while clamping the ascending aorta.A H9c2 cardiomyocyte model was constructed by stimulation of lipopolysaccharide combined with hypoxia.Semaglutide or the high mobility group box 1(HMGB1)antagonist glycyrrhizin administrations were ahead of CME and cell modeling.Cardiac function,myocardial injury markers,cell viability and morphological alternations were detected.Apoptotic and inflammatory factors,cytosolic HMGB1 and its translocation,advanced glycosylation end-product specific receptor(RAGE),and nuclear factor kappa B p65(NF-κB p65)were evaluated.RESULTS Semaglutide pretreatment ameliorated CME-induced cardiac systolic dysfunction and relieved the cardiac injury.Semaglutide attenuated myocardial apoptosis and inflammatory response following CME in vivo and in vitro.Moreover,semaglutide downregulated HMGB1 expression and suppressed its nuclear-cytoplasmic translocation.Both glycyrrhizin and semaglutide administration affected the HMGB1/RAGE/NF-κB p65 pathway after CME.CONCLUSIONS Semaglutide pretreatment attenuates CME-induced myocardial injury by suppressing apoptosis and inflammation through the HMGB1/RAGE/NF-κB p65 pathway.展开更多
Large language models(LLMs)have revolutionized AI applications across diverse domains.However,their widespread deployment has introduced critical security vulnerabilities,particularly prompt injection attacks that man...Large language models(LLMs)have revolutionized AI applications across diverse domains.However,their widespread deployment has introduced critical security vulnerabilities,particularly prompt injection attacks that manipulate model behavior through malicious instructions.Following Kitchenham’s guidelines,this systematic review synthesizes 128 peer-reviewed studies from 2022 to 2025 to provide a unified understanding of this rapidly evolving threat landscape.Our findings reveal a swift progression from simple direct injections to sophisticated multimodal attacks,achieving over 90%success rates against unprotected systems.In response,defense mechanisms show varying effectiveness:input preprocessing achieves 60%–80%detection rates and advanced architectural defenses demonstrate up to 95%protection against known patterns,though significant gaps persist against novel attack vectors.We identified 37 distinct defense approaches across three categories,but standardized evaluation frameworks remain limited.Our analysis attributes these vulnerabilities to fundamental LLM architectural limitations,such as the inability to distinguish instructions from data and attention mechanism vulnerabilities.This highlights critical research directions such as formal verification methods,standardized evaluation protocols,and architectural innovations for inherently secure LLM designs.展开更多
Subretinal injection(SI)is recognized as the most effective method for treating retinal degenerative and genetic diseases,enabling targeted delivery of therapeutic agents such as viral vectors or stem cells directly i...Subretinal injection(SI)is recognized as the most effective method for treating retinal degenerative and genetic diseases,enabling targeted delivery of therapeutic agents such as viral vectors or stem cells directly into the subretinal space(SRS).However,this procedure is typically performed under extremely constrained intraocular conditions,characterized by limited visualization,lack of tactile feedback,and the inherent fragility of retinal tissues,significantly increasing the risk of surgical complications and potential vision impairment.To overcome these challenges,an integrated force-sensing microneedle equipped with a flexible joint was developed and integrated into an ophthalmic surgical robotic system.This advanced system provides precise needle-tip pose control and real-time puncture force feedback.Leveraging these capabilities,force-guided autonomous retinal puncture was achieved,ensuring accurate and consistent drug delivery into the SRS.Comparative experiments conducted on live Bama pigs demonstrated the robotic system's superiority over manual SI techniques,as evidenced by more stable puncture trajectories,smoother insertion velocities,precise insertion depths,and a greater than 90%reduction in average puncture force,despite respiratory and cardiac-induced disturbances,thus significantly enhancing surgical precision and minimizing the risk of iatrogenic retinal injury.Postoperative evaluations further validated that the robotic approach markedly reduced drug reflux into the vitreous cavity,underscoring its reliability and safety for SI.展开更多
Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well...Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well understood.In this paper,a computational framework for multiphase combustion flow is developed and validated.Further,the effects of different injection schemes on flow combustion characteristics and engine performance are evaluated via simulation.Our findings indicate that the dominant recirculation zone in front of the primary water inlet delivers water vapor to the combustor head,providing the necessary oxidant for the ignition and combustion of Al particles.Changing the injection parameters directly affects the flame zone distribution and the ability of the recirculation zone to deliver water vapor,leading to variations in particle ignition delay.The engine combustion efficiency and specific impulse efficiency exhibit a negative correlation with injection height,peaking before declining with increased injection angle.It is shown that particle mixing degree and particle dispersion degree are closely related to engine performance.Enhanced particle mixing in front of the primary water inlet and particle dispersion behind the secondary water inlet are considered favorable approaches to improve engine performance,which promotes the particle combustion process and improves the heat-work conversion efficiency.展开更多
This paper presents the results of free-jet experiments conducted on an internal injection oblique detonation engine in a large-scale hypersonic shock tunnel.To overcome the challenges of non-uniform mixing and the fa...This paper presents the results of free-jet experiments conducted on an internal injection oblique detonation engine in a large-scale hypersonic shock tunnel.To overcome the challenges of non-uniform mixing and the failure of oblique detonation wave initiation when using liquid fuel,a combined strut-wall injection configuration was employed.Initiation was achieved by introducing a bump structure on the wedge.The results demonstrate that this strategy for mixing and initiation effectively establishes the oblique detonation wave combustion flow field.To further investigate the fuel mixing and initiation processes in the oblique detonation engine,three-dimensional numerical simulations consistent with the experimental conditions were carried out using the ReynoldsAveraged Navier-Stokes(RANS)method.The simulation results reveal that the high-speed gas flow generates shock waves as it passes through the central strut and transverse fuel jets.These shock waves are reflected by the wall,forming a series of shocks in the mixing section.The kerosene injected from the strut injectors does not react during the mixing phase.However,due to the influence of the high-temperature boundary layer,the kerosene injected through the wall undergoes precombustion.The separation zone upstream of the bump generates separation shock waves,allowing the multi-wave point to stabilize at a short distance from the leading edge of the wedge.展开更多
When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may aff...When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes.展开更多
文摘One of the most important of these emissions is fine particulate matter,which is a harmful emission of diesel engines,leading to the imposition of strict regulations.Biodiesel,with its high oxygen content,is an effective alternative to significantly reduce these emissions.In this study,rapeseed methyl ester(RME)was used as a diesel engine fuel and the emitted particulate matter was comparedwith ultra-lowsulfur diesel(ULSD).Inmost experimental studies,the emission of soot wasmeasured.In this work,the effects of injection timing,injection pressure(IP),and engine load on fine particulate matter in both nucleation and accumulation modes were studied.The results show that IP increases the number of particles in the accumulation mode while the number of particles in the crystallization mode is higher for rapeseed methyl ester(RME)than for ultra-low sulfur diesel(ULSD).Conversely,the formation rates of particles in the accumulationmode are higher for ULSD.Cumulative concentration numbers(CCN)are generally higher for RME in crystallization mode but higher for ULSD in accumulation mode.Increasing the IP reduces the CCN values.The particle size in crystallizationmode reaches a maximum of 22 nm at IPs of 800 and 1000 bar but decreases to 15 nm at 1200 bar.Most fine particles fall in the 5–100 nm diameter range.High engine loads reduce the particle size distribution in nucleationmode for both fuels,with a slight increase in particle size in nucleationmode.Thestudy concluded that the use of rapeseed methyl ester as an engine fuel benefits the environment and improves air quality due to the significant reduction in the size,number,and concentration of nano-soot particles and total particles emitted from the engine.
基金funded by National Key R&D Program of China(Grant Nos.2024YFB3612200,2023YFB3609601,2022YFB3604300,2022YFB2802801,2022YFB3604802)Natural Science Foundation of China(Grant Nos.U24A20300,62174174,62274177,62275263,62325406,62374172,62304242,62304240,62404241)+4 种基金Youth Innovation Promotion Association of CAS(Grant Nos.2022323 and 2022324)Key R&D Program of Jiangsu Province(Grant No.BE2023018-2)Basic Research Program of Jiangsu(Grant No.BK20240126)Suzhou Science and Technology Program(Grant Nos.SYC2022089,ZXL2024379,and ZXL2024376)Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2022A1515110482 and 2022A1515110004).
文摘Photonic crystal surface emitting lasers(PCSELs)utilize the Bragg diffraction of two-dimensional photonic crystals to achieve a single-mode output with a high power and a small divergence angle,and has recently attracted much attention^([1−3]).In 2023,Kyoto University reported GaAs-based 945 nm PCSELs with a continuous-wave(CW)single-mode output power of exceeding 50 W,and a narrow beam divergence angle of 0.05°,demonstrating a brightness of 1 GW·cm^(−2)·sr^(−1),which rivals those of the existing bulky lasers^([4]).
文摘Propofol(2,6-di-isopropylphenol) is a short-acting,intravenous sedative drug.^([1,2]) The pharmacologic mechanism of propofol is related to its agonistic effects on the gamma-amino butyric acid receptor.^([1-3]) Propofol injection pain(PIP) is well-known in the operating room and is commonly countered by the prophylactic administration of lidocaine.In anesthesia,PIP is encountered in 28%–90% of patients.^([4,5]) However,PIPprophylaxis does not seem to be efficacious in every population.^([6,7]) Whether procedural sedation and analgesia(PSA) in the emergency department(ED) warrants lidocaine administration is unclear.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK20231314)the National Natural Science Foundation of China(No.92168203)+4 种基金the National Key R&D Program of China(No.2022YFA1104300)the Jiangsu Cardiovascular Medicine Innovation Center(No.CXZX202210)the Suzhou“Science and Education Revitalize Health”Youth Science and Technology Project(No.KJXW2021001)the Suzhou“Science and Education Revitalize Health”Youth Science and Technology Project(No.KJXW2021001)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Myocardial infarction (MI) continues to be the primary cause of death globally. Oxidative stress in the initial phase of MI, followed by uncontrolled and excessive myocardial fibrosis, significantly impedes cardiac repair efficiency post-MI, culminating in adverse ventricular remodeling and potential heart failure. To address the diverse pathological stages of MI, an injectable composite hydrogel containing versatile nanoparticles was developed. In this study, mesoporous silicon nanoparticles (MSNs) served as carriers for encapsulating microRNA-29b (miR-29b) mimics with antifibrotic activity, subsequently coated with a complex of natural antioxidant tannic acid and zinc ions (TA/Zn). These nanoparticles were then embedded into a biocompatible alginate hydrogel to enhance retention within the infarcted myocardium. Upon injection into the infarcted region of MI mice, the composite hydrogel gradually released the nanoparticles as it degraded. Initially, the TA/Zn complex on the outer layer scavenged reactive oxygen species, thereby inhibiting cell apoptosis. The subsequent dissociation of the TA/Zn complex led to the release of the encapsulated miR-29b mimics that could inhibit the activation of cardiac fibroblasts and collagen production, thereby alleviating fibrosis progression. Overall, this composite hydrogel demonstrated the potential to reduce infarct size and improve cardiac function, suggesting its promise as a synergistic therapeutic approach for repairing infarcted myocardium.
文摘Following high-level diplomacy,a recent forum has bridged China and Spanish-and Portuguese-speaking countries by injecting substance into cooperation frameworks through a new education alliance and concrete projects.
文摘This paper investigates the application of Direct Current Atmospheric Plasma Spraying(DC-APS)as a versatile thermal spray technique for the application of coatings with tailored properties to various substrates.The process uses a high-speed,high-temperature plasma jet to melt and propel the feedstock powder particles,making it particularly useful for improving the performance and durability of components in renewable energy systems such as solar cells,wind turbines,and fuel cells.The integration of nanostructured alumina(Al_(2)O_(3))thin films into multilayer coatings is considered a promising advancement that improves mechanical strength,thermal stability,and environmental resistance.The study highlights the importance of understanding injection parameters and their impact on coating properties and uses simulation tools such as the Jets&Poudres(JP)code for in-depth analysis.Furthermore,the paper discusses the implementation of Artificial Neural Networks(ANN)to optimize the coating process by predicting flight characteristics and improving operating conditions.The results show that ANN models are effective in achieving highly accurate prediction values,highlighting the potential of AI in improving thermal spray technology.
文摘Nonobstructive azoospermia(NOA)is the most challenging and complex clinical scenario for infertile men.Besides circumstances such as hypogonadotropic hypogonadism,surgical sperm retrieval is typically necessary,and microdissection testicular sperm extraction(micro-TESE)is the procedure of choice for men with NOA desiring to father children with their own gametes.Micro-TESE results in the highest numbers of sperm cells retrieved for use with in vitro fertilization/intracytoplasmic sperm injection(ICSI)in comparison to all other techniques for surgical sperm retrieval in men with NOA.Several factors may affect sperm retrieval rate and ICSI outcomes,including the patient’s age,testicular volume,histopathological and genetic profile,and serum hormone levels.This article aims to review the medical literature describing predictors of successful micro-TESE and the outcomes of ICSI in men with NOA.
基金Project(2011CB606306)supported by the National Basic Research Program of ChinaProject(FRF-TP-10-003B)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(51274040)supported by the National Natural Science Foundation of China
文摘The evolution of stresses due to inhomogeneity in metal injection molding （MIM） parts during sintering was investigated. The sintering model of porous materials during densification process was developed based on the continuum mechanics and thermal elasto-viseoplastic constitutive law. Model parameters were identified from the dilatometer sintering experiment. The real density distribution of green body was measured by X-ray computed tomography （CT）, which was regarded as the initial condition of sintering model. Numerical calculation of the above sintering model was carried out with the finite element soRware Abaqus, through the user-defined material mechanical behavior （UMAT）. The calculation results showed that shrinkages of low density regions were faster than those of high density regions during sintering, which led to internal stresses. Compressive stresses existed in high density regions and tensile stresses existed in low density regions. The densification of local regions depended on not only the initial density, but also the evolution of stresses during the sintering stage.
文摘With its growth in spacecraft control applications,the microcontroller(MCU)becomes increasingly sensitive to radiation and the risks of system failure.In a radiation environment,the MCU is vulnerable to impacts from high-energy particles,which can lead to single-event effect(SEE)that disrupt normal system operations.The pipeline of MCU,being the core structure of the system,is particularly susceptible to single-event upset(SEU)and potentially causes execution failures.However,existing radiation-hardening techniques offer limited effectiveness for pipelines.To enhance SEU resistance,this study focused on a 32-bit MCU core with eight pipeline stages,proposing a pipeline hardening approach that utilizes lockstep technology to improve fault tolerance.Signals from two processors were compared including register write data,register contents and pre-fetched instructions.Any discrepancies triggered error flags to indicate faults.When an error flag was raised,recovery was initiated through an interrupt.The interrupt handler then retrieved state information from the advanced peripheral bus(APB)slave module to restore the CPU's operational state and resume execution.By combining hardware-based state preservation with software-driven error recovery,the proposed solution demonstrated significant improvements in fault tolerance rates and performance compared to traditional checkpoint-based techniques.After completing the pipeline hardening design,a fault injection platform was utilized in this paper to simulate real-world error conditions on internal processor modules.The platform was developed based on the circuit's register-transfer-level(RTL)design and statistical results.The fault injection platform was performed by automatically finding all registers within the target design.The register values were forced to upset at the tens of nanoseconds scale in the RTL description of the circuit's design.After running the circuit's functional simulation,the statistics of the faults in registers were displayed on the platform,which evaluated the influence of SEU.The vulnerability of SEU in the circuit could be observed from the results of the soft error statistics.The post-hardening soft error rates were then measured and compared to pre-hardening data,providing a quantitative evaluation of the improvements.Using this method,the soft error rates of the modules in the MCU core such as PFU,DPU,and Cache AXIM are 40.07%,26.36%,and 27.29%respectively before hardening.The soft error rates of modules mentioned above are reduced to 0%,0.69%,and 1.11%after hardening.The hardened and non-hardened designs of the entire core were implemented in FPGA.The total resource utilization of the triple mode redundancy(TMR)is 111984,as indicated by the number of look-up tables(LUTs)and registers consumed in the FPGA.The total resource utilization of this work is 78034,and the ratio of resource utilization between this work and TMR is approximately 69.68%.The error recovery time for the hardened MCU processor was analyzed using the completion cycles of a bubble sort algorithm as a benchmark.In this paper,the average recovery cycle using the software checkpoint roll-back method is 36479.06,and the average recovery cycle using this work is 26922.5.The ratio of recovery cycles between this work and checkpoint roll-back is about 73.8%.Assessments through random fault injection and FPGA implementation indicate that this approach effectively reduces processor faults caused by soft errors while optimizing resource utilization and efficiency over triplemodular redundancy.
基金financially supported by the National Natural Science Foundation of China(Nos.82272472 and 52373146)。
文摘Early knee osteoarthritis(KOA)is characterized by progressive degeneration of the articular cartilage,synovial inflammation,and excessive accumulation of reactive oxygen species(ROS).At present,intra-articular injection of hyaluronic acid(HA)is widely used to alleviate symptoms;however,its lubrication persistence,antioxidant,and anti-inflammatory abilities are limited,and it is difficult to effectively delay the early process of cartilage degeneration.Based on this,hyaluronic acid-g-lipoic acid(HA-LA)was synthesized by esterification reaction,and HA-LA microspheres were prepared by a reversed-phase emulsion method,which was combined with a macromolecular HA-LA solution to form injectable hydrogels.The objective of this study was to evaluate the efficacy of an injectable hydrogel based on hyaluronic acid-g-lipoic acid microspheres(HA-LA MS)for the treatment of KOA and to verify its injectability,lubricity,reactive oxygen species(ROS)scavenging ability,and anti-inflammatory effects.The results show that the HA-LA MS hydrogel has excellent shear thinning characteristics and continuous injectability,and its microsphere structure significantly reduces the interfacial friction coefficient through the rolling effect.In vitro experiments have shown that the hydrogel can efficiently scavenge ROS,reduce the expression of inflammatory factors,and is non-cytotoxic.The HA-LA MS injectable hydrogel has excellent lubricity,ROS scavenging ability,and anti-inflammatory effects in vivo,which can effectively delay the degeneration of early KOA cartilage,and its efficacy is significantly better than that of traditional hyaluronic acid,making it a promising intra-articular injection preparation.
基金Supported by the Special Funds of Jiangsu Provincial Key Research and Development Projects,No.BE2019612Scientific Research Project Cooperated by Lanzhou Biotechnology Development Co.,Ltd.+3 种基金the Key R&D Program of Jiangsu Science and Technology Project,No.BE2022049 and No.BE2022049-1National Natural Science Foundation of China,No.82171249Nanjing Rehabilitation Medicine Center ProjectJiangsu Provincial Health Commission Special Fund for Aging and Health.
文摘BACKGROUND The previous studies have primarily focused on the influence of botulinum toxin A(BoNT-A)injection on emotions during the period of peak motor symptom improvement in blepharospasm patients,based on facial feedback hypothesis.AIM To evaluate the sustained anxiolytic and antidepressant effects of BoNT-A in blepharospasm patients beyond motor symptom control.METHODS We recruited benign essential blepharospasm patients with BoNT-A treatment and collected their data to compare scale scores of Jankovic Rating Scale,Blepharospasm Disability Index,Self-rating Anxiety Scale(SAS),Self-rating Depression Scale(SDS),Hamilton Anxiety Scale and Hamilton Depression Scale between pretreatment(baseline)and pre-reinjection(treatment),to further assess the effects of repeated treatments with BoNT by using sub-group analyses in the certain special states.RESULTS A total of 21 eligible blepharospasm patients were with the mean age of 58.4 years and a male-to-female ratio of 1:6.Significantly decreases in the subscale scores of SDS and SAS,including SDS well-being index,decreased capacity and hard to decide,SAS inability to sit still and headache were showed at post-a single BoNT-A injection when scale scores of Jankovic Rating Scale and Blepharospasm Disability Index were matched between baseline and posttreatment.With each additional BoNT-A injection,the odds ratio of patients with the moderate depressive symptoms decreased by 92.6%.Moreover,BoNT treatment remained a decrease in the subscale scores of SDS and SAS in patients with repeated injections.CONCLUSION This study is to demonstrate that repeated BoNT-A injection have a long-lasting relief for anxiety and depressive symptoms in blepharospasm even after its motor symptom-modulating effects have diminished.
文摘Objective:To compare the clinical efficacy and safety of intravitreal injection of faricimab and conbercept in the treatment of diabetic macular edema(DME).Methods:A total of 50 patients diagnosed with DME in our hospital from January 2023 to May 2025 were selected and randomly divided into an observation group and a control group,with 25 cases in each group,using a random number table method.The observation group received intravitreal injection of faricimab,while the control group received intravitreal injection of conbercept.Both groups adopted a loading phase plus maintenance phase treatment regimen.The best-corrected visual acuity(BCVA,expressed in logMAR)and central subfield thickness(CST)of the two groups were compared before treatment and at 1,3,and 6 months after treatment,and the incidence of adverse events during treatment was recorded.Results:The logMAR BCVA in the observation group was lower than that in the control group at 3 and 6 months after treatment(both p<0.05).The CST in the observation group was smaller than that in the control group at 1,3,and 6 months after treatment(all p<0.05).There was no statistically significant difference in the overall incidence of adverse events between the two groups(χ^(2)=0.189,p=0.663).Conclusion:Both intravitreal injections of faricimab and conbercept are effective in improving visual acuity and reducing macular edema in patients with DME,with good safety profiles.However,faricimab demonstrates superior efficacy in the medium to long term(3 and 6 months)compared to conbercept,making it more suitable for long-term treatment of patients with DME.
文摘Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Although these procedures are now performed in more controlled and medically supervised environments,their long-term outcomes remain poorly understood.The promotion of such medical treatments contributes to an increasing interest among adult males in self-injection as a method to alleviate psychological distress associated with penile size concerns.At the same time,access to injectable substances through unofficial or unregulated sources has become increasingly easy.Tor our knowledge,we report the first documented case of self-injection with Garamycin®(gentamicin)cream,contributing to the literature on the often multidisciplinary management of penile enlargement injections,a field still lacking well-established guidelines.Case Description:This case report describes a young patient who self-injected Garamycin®into the penis for the purpose of enlargement.He presented to our urology department with worsening symptoms,including severe and poorly tolerated pain.His primary request was prompt relief of pain while preserving,as much as possible,the aesthetic appearance and functional integrity of his penis.This case required a multi-stage surgical approach to salvage the penis and preserve both its structural integrity and functional outcome.Conclusions:To our knowledge,this case report documents the first reported instance of Garamycin®injection performed for the purpose of penile enlargement.It provides insight into the clinical course of such penile cream injections,demonstrates that a two-stage scrotal flap can achieve both functional and aesthetic outcomes,and highlights the importance of comprehensive management particularly addressing the traumatic impact of penile deformity secondary to inflammation and/or infection,as well as the body dysmorphic concerns often associated with these cases.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,China(No.2021B1515140007).
文摘The Southern Advanced Photon Source(SAPS)is a diffraction-limited synchrotron light source under design,which employs longitudinal injection as its primary injection scheme.This kind of injection scheme requires that the injected beam has a short bunch length and low emittance,and the preferred injector should offer high stability and low cost.Therefore,an injector based on a booster synchrotron was developed.The proposed injector includes a 250 MeV linac,a booster synchrotron that ramps the beam energy to 3.5 GeV,and two beam transport lines to ensure efficient beam delivery and beam quality preservation.The linac utilizes a thermionic high-voltage DC gun for reliable operation and features a bunching system with an advanced focusing system to preserve the emittance.To meet the injection requirements of the SAPS,a comprehensive design for the booster has been conducted.The booster synchrotron employs a threefold lattice structure,incorporating modified theoretical minimum emittance cells with a small momentum compaction factor and a high voltage to achieve an emittance of 3.98 nm rad and a bunch length of 4.8 mm.The injector has the potential to deliver a high charge,reducing the injection period of the storage ring to less than 1 min.Simulations demonstrated the expected performance,with a transmission efficiency of 90%,confirming its capability to meet the injection requirement of the SAPS storage ring.This design offers a stable and efficient solution for the SAPS.
文摘BACKGROUND Coronary microembolization(CME)is the major leading cause of perioperative myocardial injury during coronary revascularization.Semaglutide exerts multiple protective biological activities,but its cardioprotective effects on CME remain unclear.Thus,this experiment studied the impact of semaglutide on CME-induced myocardial injury.METHODS A rat CME model was generated by injecting microspheres into the left ventricle while clamping the ascending aorta.A H9c2 cardiomyocyte model was constructed by stimulation of lipopolysaccharide combined with hypoxia.Semaglutide or the high mobility group box 1(HMGB1)antagonist glycyrrhizin administrations were ahead of CME and cell modeling.Cardiac function,myocardial injury markers,cell viability and morphological alternations were detected.Apoptotic and inflammatory factors,cytosolic HMGB1 and its translocation,advanced glycosylation end-product specific receptor(RAGE),and nuclear factor kappa B p65(NF-κB p65)were evaluated.RESULTS Semaglutide pretreatment ameliorated CME-induced cardiac systolic dysfunction and relieved the cardiac injury.Semaglutide attenuated myocardial apoptosis and inflammatory response following CME in vivo and in vitro.Moreover,semaglutide downregulated HMGB1 expression and suppressed its nuclear-cytoplasmic translocation.Both glycyrrhizin and semaglutide administration affected the HMGB1/RAGE/NF-κB p65 pathway after CME.CONCLUSIONS Semaglutide pretreatment attenuates CME-induced myocardial injury by suppressing apoptosis and inflammation through the HMGB1/RAGE/NF-κB p65 pathway.
基金supported by 2023 Higher Education Scientific Research Planning Project of China Society of Higher Education(No.23PG0408)2023 Philosophy and Social Science Research Programs in Jiangsu Province(No.2023SJSZ0993)+2 种基金Nantong Science and Technology Project(No.JC2023070)Key Project of Jiangsu Province Education Science 14th Five-Year Plan(Grant No.B-b/2024/02/41)the Open Fund of Advanced Cryptography and System Security Key Laboratory of Sichuan Province(Grant No.SKLACSS-202407).
文摘Large language models(LLMs)have revolutionized AI applications across diverse domains.However,their widespread deployment has introduced critical security vulnerabilities,particularly prompt injection attacks that manipulate model behavior through malicious instructions.Following Kitchenham’s guidelines,this systematic review synthesizes 128 peer-reviewed studies from 2022 to 2025 to provide a unified understanding of this rapidly evolving threat landscape.Our findings reveal a swift progression from simple direct injections to sophisticated multimodal attacks,achieving over 90%success rates against unprotected systems.In response,defense mechanisms show varying effectiveness:input preprocessing achieves 60%–80%detection rates and advanced architectural defenses demonstrate up to 95%protection against known patterns,though significant gaps persist against novel attack vectors.We identified 37 distinct defense approaches across three categories,but standardized evaluation frameworks remain limited.Our analysis attributes these vulnerabilities to fundamental LLM architectural limitations,such as the inability to distinguish instructions from data and attention mechanism vulnerabilities.This highlights critical research directions such as formal verification methods,standardized evaluation protocols,and architectural innovations for inherently secure LLM designs.
基金supported in part by the National Key R&D Program of China(No.2023YFB4705801)the Progect of Medical Engineering Laboratory of Chinese PLA General Hospital(Grant No.2022SYSZZKY13)+1 种基金the National Natural Science Foundation of China(Nos.52175008 and 92048301)the National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(Grant No.52025054)。
文摘Subretinal injection(SI)is recognized as the most effective method for treating retinal degenerative and genetic diseases,enabling targeted delivery of therapeutic agents such as viral vectors or stem cells directly into the subretinal space(SRS).However,this procedure is typically performed under extremely constrained intraocular conditions,characterized by limited visualization,lack of tactile feedback,and the inherent fragility of retinal tissues,significantly increasing the risk of surgical complications and potential vision impairment.To overcome these challenges,an integrated force-sensing microneedle equipped with a flexible joint was developed and integrated into an ophthalmic surgical robotic system.This advanced system provides precise needle-tip pose control and real-time puncture force feedback.Leveraging these capabilities,force-guided autonomous retinal puncture was achieved,ensuring accurate and consistent drug delivery into the SRS.Comparative experiments conducted on live Bama pigs demonstrated the robotic system's superiority over manual SI techniques,as evidenced by more stable puncture trajectories,smoother insertion velocities,precise insertion depths,and a greater than 90%reduction in average puncture force,despite respiratory and cardiac-induced disturbances,thus significantly enhancing surgical precision and minimizing the risk of iatrogenic retinal injury.Postoperative evaluations further validated that the robotic approach markedly reduced drug reflux into the vitreous cavity,underscoring its reliability and safety for SI.
基金supported by the National Natural Science Foundation of China(No.22305053)the Fundamental Research Funds for the Central Universities,China(No.3072024WD0201)。
文摘Powder-Fueled Water Ramjet Engine(PFWRE)is the most promising powerplant in underwater high-speed propulsion.However,the effect of powder injection mode on its performance and the mechanism of this effect are not well understood.In this paper,a computational framework for multiphase combustion flow is developed and validated.Further,the effects of different injection schemes on flow combustion characteristics and engine performance are evaluated via simulation.Our findings indicate that the dominant recirculation zone in front of the primary water inlet delivers water vapor to the combustor head,providing the necessary oxidant for the ignition and combustion of Al particles.Changing the injection parameters directly affects the flame zone distribution and the ability of the recirculation zone to deliver water vapor,leading to variations in particle ignition delay.The engine combustion efficiency and specific impulse efficiency exhibit a negative correlation with injection height,peaking before declining with increased injection angle.It is shown that particle mixing degree and particle dispersion degree are closely related to engine performance.Enhanced particle mixing in front of the primary water inlet and particle dispersion behind the secondary water inlet are considered favorable approaches to improve engine performance,which promotes the particle combustion process and improves the heat-work conversion efficiency.
基金National Natural Science Foundation of China(No.52006181)。
文摘This paper presents the results of free-jet experiments conducted on an internal injection oblique detonation engine in a large-scale hypersonic shock tunnel.To overcome the challenges of non-uniform mixing and the failure of oblique detonation wave initiation when using liquid fuel,a combined strut-wall injection configuration was employed.Initiation was achieved by introducing a bump structure on the wedge.The results demonstrate that this strategy for mixing and initiation effectively establishes the oblique detonation wave combustion flow field.To further investigate the fuel mixing and initiation processes in the oblique detonation engine,three-dimensional numerical simulations consistent with the experimental conditions were carried out using the ReynoldsAveraged Navier-Stokes(RANS)method.The simulation results reveal that the high-speed gas flow generates shock waves as it passes through the central strut and transverse fuel jets.These shock waves are reflected by the wall,forming a series of shocks in the mixing section.The kerosene injected from the strut injectors does not react during the mixing phase.However,due to the influence of the high-temperature boundary layer,the kerosene injected through the wall undergoes precombustion.The separation zone upstream of the bump generates separation shock waves,allowing the multi-wave point to stabilize at a short distance from the leading edge of the wedge.
文摘When a porous rock is subjected to overall compressive loading,either increasing pore pressure or decreasing confining pressure could result in rock failure.The stress path and the applied pressure change rate may affect the initiation and propagation of fractures within brittle materials.Understanding the physical mechanisms leading to failure is crucial for underground engineering applications and geo-energy exploration and storage.We conducted triaxial compression experiments on porous Bentheim sandstone samples at different stress paths and pressure change rates.First,at a constant confining pressure of 35 MPa and pore pressure of 5 MPa,intact cylindrical samples were axially loaded up to about 85%of the peak strength.Subsequently,the axial piston position was fixed,and then either the pore pressure was increased or the confining pressure was decreased at two different rates(0.5 MPa/min or 2 MPa/min),leading to final catastrophic failure.The mechanical results revealed that samples subjected to higher rates of decreasing effective confining pressure exhibited larger stress drop rates,higher slip rates,higher total breakdown work,higher rates of acoustic emissions(AEs)before failure,and higher post-failure AE decay rates.In contrast,the applied stress path did not significantly affect rock failure characteristics.Comparison of located AE events with post-mortem microstructures of deformed samples shows a good agreement.The AE source type determined from the P-wave first-motion polarity shows that shear failure dominated the fracture process when approaching failure.Gutenberg-Richter b-values revealed a significant decrease before failure in all tests.Our results indicate that,in contrast to the stress path,the rate of effective stress change strongly affects fracturing behavior and AE rate changes.
