In order to synchronize the elements of the EAST Neutral Beam Injector （NBI） spatially located in several places, a distributed Timing System （TS） is developed in this paper. The timing system provides a clock ref...In order to synchronize the elements of the EAST Neutral Beam Injector （NBI） spatially located in several places, a distributed Timing System （TS） is developed in this paper. The timing system provides a clock reference for synchronization and an interlock protection of the EAST NBI system. It sends timing signals to field devices, controls the pulse widths of the timing sequences, and provides a sampling clock for the Data Acquisition System （DAS）. The timing system also generates analog waveforms to control power supplies and gas supplies according to the operator＇s configuration. The timing system is developed on a PXI （PCI eXtensions for Instrumentation） platform consisting of a LabVIEW workstation and a timing control terminal. The timing control terminal consists of a timing node and several control interface crates. Two timing nodes are configured in one beam line. Each node is responsible for the timing sequence, analog generation and feedback control for one ion source. The architecture and implementation of the timing system are presented in this paper.展开更多
Large accelerator facilities require clocks and triggers with high accuracy to synchronize equipment and devices. A new femtosecond timing system was designed to meet the demands of new facilities. In this system, the...Large accelerator facilities require clocks and triggers with high accuracy to synchronize equipment and devices. A new femtosecond timing system was designed to meet the demands of new facilities. In this system, the radio-frequency signal is modulated in a continuous-wave laser carrier with frequency stabilization, and timing events are distributed in the same fiber. The phase drift is detected precisely, based on the principle of the Michelson interferometer. The phase drift is compensated with coarse and fine correctors afterward. We aim to realize the stable transmission of the RF signal and timing events for a long distance and duration, with the phase drift and additive jitter in femtoseconds. After the extension, the system will become a complete solution for the clock-and-trigger distribution of synchrotron radiation facilities, free-electron lasers, and other accelerators. The physics design, simulation analysis, and preliminary results are included in the paper.展开更多
Volumetric efficiency and air charge estimation is one of the most demanding tasks in control of today's internal combustion engines.Specifically,using three-way catalytic converter involves strict control of the ...Volumetric efficiency and air charge estimation is one of the most demanding tasks in control of today's internal combustion engines.Specifically,using three-way catalytic converter involves strict control of the air/fuel ratio around the stoichiometric point and hence requires an accurate model for air charge estimation.However,high degrees of complexity and nonlinearity of the gas flow in the internal combustion engine make air charge estimation a challenging task.This is more obvious in engines with variable valve timing systems in which gas flow is more complex and depends on more functional variables.This results in models that are either quite empirical(such as look-up tables),not having interpretability and extrapolation capability,or physically based models which are not appropriate for onboard applications.Solving these problems,a novel semi-empirical model was proposed in this work which only needed engine speed,load,and valves timings for volumetric efficiency prediction.The accuracy and generalizability of the model is shown by its test on numerical and experimental data from three distinct engines.Normalized test errors are 0.0316,0.0152 and 0.24 for the three engines,respectively.Also the performance and complexity of the model were compared with neural networks as typical black box models.While the complexity of the model is less than half of the complexity of neural networks,and its computational cost is approximately 0.12 of that of neural networks and its prediction capability in the considered case studies is usually more.These results show the superiority of the proposed model over conventional black box models such as neural networks in terms of accuracy,generalizability and computational cost.展开更多
A piece of equipment designed under a multi-disciplinary project in Shandong University of Science and Technology is described.The purpose is to indicate speech-time status to speakers in debates by presenting a three...A piece of equipment designed under a multi-disciplinary project in Shandong University of Science and Technology is described.The purpose is to indicate speech-time status to speakers in debates by presenting a three-light output The speech length may be programmed by the user with a combination of buttons and LCD display.The system is portable and microcontroller-based,using on-chip timers for accurate measurement of durations.展开更多
BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therape...BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therapeutic modality to improve healing outcomes in DFU management.AIM To evaluate the efficacy of UAWD in treating DFUs on wound closure rates,treatment duration,and quality of life outcomes.METHODS This systematic review and meta-analysis followed PRISMA guidelines,systematically searching PubMed,Embase,Web of Science,and the Cochrane Library with no date restrictions.Randomized controlled trials(RCTs)that evaluated the efficacy of UAWD in DFU treatment were included.Data were independently extracted by two reviewers,with discrepancies resolved through consensus or third-party consultation.The risk of bias was assessed using the Cochrane tool.χ2 and I2 statistics assessed heterogeneity,informing the use of fixed or random-effects models for meta-analysis,supplemented by sensitivity analysis and publication bias assessment through funnel plots and Egger's test.RESULTS From 1255 articles,seven RCTs met the inclusion criteria.The studies demonstrated that UAWD significantly reduced DFU healing time(standardized mean difference=-0.78,95%CI:-0.97 to-0.60,P<0.001)and increased healing rates(odds ratio=9.96,95%CI:5.99 to 16.56,P<0.001)compared to standard care.Sensitivity analysis confirmed the stability of these results,and no significant publication bias was detected.CONCLUSION UAWD is a promising adjunctive treatment for DFUs,significantly reducing healing times and increasing healing rates.These findings advocate for the integration of UAWD into standard DFU care protocols.展开更多
The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled p...The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled phased array antenna system is a necessary trend for the future development of the phased array,and it is also a major focus and difficulty in the current research of integrated microwave photonics.This paper firstly introduces the basic principle and development history of optical true time delay phased array antenna system based on microwave photonics,and briefly introduces the main implementation methods and integration platform of optical true time delay.Then,the application and development prospect of optical true time delay technology in beam control of phased array antenna system are mainly presented.Finally,according to the current research progress,the possible research directions of integrated optically controlled phased array antenna systems in the future are proposed.展开更多
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at...Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.展开更多
The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process th...The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.展开更多
BACKGROUND Meniscal tears are one of the most common knee injuries.After the diagnosis of a meniscal tear has been made,there are several factors physicians use to guide clinical decision-making.The influence of time ...BACKGROUND Meniscal tears are one of the most common knee injuries.After the diagnosis of a meniscal tear has been made,there are several factors physicians use to guide clinical decision-making.The influence of time between injury and isolated meniscus repair on patient outcomes is not well described.Assessing this relationship is important as it may influence clinical decision-making and can add to the preoperative patient education process.We hypothesized that increasing the time from injury to meniscus surgery would worsen postoperative outcomes.AIM To investigate the current literature for data on the relationship between time between meniscus injury and repair on patient outcomes.METHODS PubMed,Academic Search Complete,MEDLINE,CINAHL,and SPORTDiscus were searched for studies published between January 1,1995 and July 13,2023 on isolated meniscus repair.Exclusion criteria included concomitant ligament surgery,incomplete outcomes or time to surgery data,and meniscectomies.Patient demographics,time to injury,and postoperative outcomes from each study were abstracted and analyzed.RESULTS Five studies met all inclusion and exclusion criteria.There were 204(121 male,83 female)patients included.Three of five(60%)studies determined that time between injury and surgery was not statistically significant for postoperative Lysholm scores(P=0.62),Tegner scores(P=0.46),failure rate(P=0.45,P=0.86),and International Knee Documentation Committee scores(P=0.65).Two of five(40%)studies found a statistically significant increase in Lysholm scores with shorter time to surgery(P=0.03)and a statistically significant association between progression of medial meniscus extrusion ratio(P=0.01)and increasing time to surgery.CONCLUSION Our results do not support the hypothesis that increased time from injury to isolated meniscus surgery worsens postoperative outcomes.Decision-making primarily based on injury interval is thus not recommended.展开更多
Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy sync...Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy synchrotron booster,a 6-GeV synchrotron storage ring(SR),and three e-beam transport lines for injection and extraction among accelerators.A global timing system(GTS)covers the timing needs for all accelerator,beamline,and experiment systems.The GTS is designed to coordinate the injection processes and various measurements and protections.Most systems require that the RMS jitter of the GTS signal is less than 30 ps,while the trigger jitters for the electron gun and SR injection and extraction kickers are less than 10 ps.Method The HEPS GTS is an event-based timing system based on MicroTCA.4 hardware architecture.The MicroTCA.4300 series products from the micro-research Finland Oy are implemented in the HEPS GTS system.Results and conclusions The RMS jitter,integrated from 1 Hz to 10 MHz,of the 166.6 MHz event clock is 5.489 ps.The RMS jitter of TTL outputs is less than 30 ps.This paper reports the design of the HEPS GTS,which satisfies all of the HEPS physics requirements for timing with preliminary test results shown.展开更多
In this article,we discussed the article by Sohail et al,published in a recent issue of the World Journal of Gastrointestinal Endoscopy.This study highlights the benefits of performing cholecystectomy(CCY)during the s...In this article,we discussed the article by Sohail et al,published in a recent issue of the World Journal of Gastrointestinal Endoscopy.This study highlights the benefits of performing cholecystectomy(CCY)during the same hospitalization for patients with acute cholangitis(AC)associated with gallstones.Specifically,same-admission CCY is associated with significantly lower 30-day readmission rates compared with interval CCY.Furthermore,it has been associated with reduced mortality rates and reduced recurrence of biliary symptoms.Despite these advantages,the procedure is chosen in only a minority of eligible patients.This gap between evidence and practice highlights the need for updated clinical guidelines and further research to optimize the timing of CCY in the management of AC.展开更多
Over more than a decade of development,medium to deep shale gas reservoirs have faced rapid production declines,making sustained output challenging.To harness remaining reserves effectively,advanced fracturing techniq...Over more than a decade of development,medium to deep shale gas reservoirs have faced rapid production declines,making sustained output challenging.To harness remaining reserves effectively,advanced fracturing techniques such as infill drilling are essential.This study develops a complex fracture network model for dual horizontal wells and a four-dimensional in-situ stress evolution model,grounded in elastic porous media theory.These models simulate and analyze the evolution of formation pore pressure and in-situ stress during production.The investigation focuses on the influence of infill well fracturing timing on fracture propagation patterns,individual well productivity,and the overall productivity of well clusters.The findings reveal that,at infill well locations,the maximum horizontal principal stress undergoes the most significant reduction,while changes in the minimum horizontal principal stress and vertical stress remain minimal.The horizontal stress surrounding the infill well may reorient,potentially transitioning the stress regime from strike-slip to normal faulting.Delays in infill well fracturing increase lateral fracture deflection and diminish fracture propagation between wells.Considering the stable production phase and cumulative gas output of the well group,the study identifies an optimal timing for infill fracturing.Notably,larger well spacing shifts the optimal timing to a later stage.展开更多
Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and n...Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and noise subspaces,has been successfully applied for this purpose.However,conventional subspace selection methods relying on fixed thresholds are sensitive to variations in large eigenvalues.Furthermore,the complex disturbances during rotor operation and measurement complicate the identification of blade vibration characteristics.To overcome these challenges,this paper proposes Adaptive Subspace Separation(ASS)and Local Spectral Centroid(LSC)methods to improve the adaptability of subspace selection and the stability of frequency identification,respectively.The impacts of overestimating and underestimating the subspace dimensions on MUSIC's performance are derived mathematically.Simulation and experiments demonstrate the effectiveness of proposed approaches:ASS offers more accurate and stable subspace dimension selection and tracking,while LSC reduces the standard deviation of estimated frequencies by 30 percent.展开更多
The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of ...The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of variability in the timing of seasonal sea ice retreat on the flux and composition of sinking particulate matter remains to be elucidated.In this study,we deployed sediment traps in Prydz Bay during the austral summers of 2019/2020 and 2020/2021,noting that sea ice melting occurred approximately one and a half months earlier in the former summer compared to the latter.We analyzed sediment trap data,which included total mass flux(TMF),particulate organic carbon(POC),biogenic silica(BSi),particulate inorganic carbon,and lithogenic particle(Litho)fluxes,as well as the stable isotopesδ^(13)C andδ^(15)N of particulate organic matter(POM).Additionally,we incorporated remote sensing data on sea ice concentration and chlorophyll a.This dramatic delay in sea ice melting timing could result in a significant increase in TMF,BSi and POC fluxes in the summer of 2020/2021 compared to 2019/2020.Elevated BSi fluxes and more ^(13)C-depleted POC in the austral summer of 2020/2021 suggest that the delayed melting of sea ice may have stimulated the productivity of centric diatoms.Furthermore,the higher BSi/POC ratio and more negativeδ^(15)N values of POM,along with a reduced presence of krill in the traps,indicate a diminished grazing pressure from zooplankton,which collectively enhanced the sedimentation efficiency of POC during the austral summer of 2020/2021.These findings highlight the critical role of sea ice melting timing in regulating productivity,flux and composition of sinking particulate matter in the Prydz Bay ecosystem,with significant implications for carbon cycling in polar oceans.展开更多
Laser frequency microcombs provide a series of equidistant,coherent frequency markers across a broad spectrum,enabling advancements in laser spectroscopy,dense optical communications,precision distance metrology,and a...Laser frequency microcombs provide a series of equidistant,coherent frequency markers across a broad spectrum,enabling advancements in laser spectroscopy,dense optical communications,precision distance metrology,and astronomy.Here,we design and fabricate silicon nitride,dispersion-managed microresonators that effectively suppress avoided-mode crossings and achieve close-to-zero averaged dispersion.Both the stochastic noise and mode-locking dynamics of the resonator are numerically and experimentally investigated.First,we experimentally demonstrate thermally stabilized microcomb formation in the microresonator across different mode-locked states,showing negligible center frequency shifts and a broad frequency bandwidth.Next,we characterize the femtosecond timing jitter of the microcombs,supported by precise metrology of the timing phase and relative intensity noise.For the single-soliton state,we report a relative intensity noise of−153.2 dB∕Hz,close to the shot-noise limit,and a quantum-noise–limited timing jitter power spectral density of 0.4 as 2∕Hz at a 100 kHz offset frequency,measured using a self-heterodyne linear interferometer.In addition,we achieve an integrated timing jitter of 1.7 fs±0.07 fs,measured from 10 kHz to 1 MHz.Measuring and understanding these fundamental noise parameters in high clock rate frequency microcombs is critical for advancing soliton physics and enabling new applications in precision metrology.展开更多
BACKGROUND Bile duct leaks(BDLs)are serious postsurgical adverse events.Typically,conservative management with ab-dominal drainage is the initial treatment option.However,prolonged abdominal drainage without improveme...BACKGROUND Bile duct leaks(BDLs)are serious postsurgical adverse events.Typically,conservative management with ab-dominal drainage is the initial treatment option.However,prolonged abdominal drainage without improvement can lead to biliary stricture and delay the optimal timing of endoscopic retrograde cholangiopancreatography(ERCP).AIM To identify the optimal timing for ERCP and the period during which clinical observation with conservative management is acceptable,balancing ERCP success and the risk of biliary strictures.METHODS We conducted a multicenter retrospective study involving 448 patients with BDLs between November 2002 and November 2022.The patients were divided into four groups based on the timing of ERCP:3 days,7 days,14 days,and 21 days.The primary outcome was clinical success,defined as the resolution of BDL and related symptoms within 6 months without additional percutaneous drainage,surgery,or death.The secondary outcome was incidence of biliary strictures.Univariate and multivariate logistic regression analyses were performed to identify factors associated with ERCP success and biliary stricture occurrence.RESULTS In a cohort of 448 consecutive patients diagnosed with BDLs,354 were excluded,leaving 94 patients who underwent ERCP.Clinical success was achieved in 84%of cases(79/94),with a median ERCP timing of 20 days(9.5-35.3 days).Biliary strictures were identified in 29(30.9%)patients.Performing ERCP within 3 weeks,compared to after 3 weeks,was associated with higher success rates[92.0%(46/50)vs 75.0%(33/44),P=0.032]and a lower incidence of biliary stricture incidence[18.0%(9/50)vs 45.5%(20/44),P=0.005].Subsequent multivariate analysis confirmed the association with higher success rates(odds ratio=4.168,P=0.045)and lower biliary stricture rates(odds ratio=0.256,P=0.007).CONCLUSION Performing ERCP for BDLs within 3 weeks may be associated with a higher success rate and a lower biliary stricture rate.If patients with BDLs do not respond to conservative treatment,ERCP is suggested to be performed within 3 weeks.展开更多
Background:Rehabilitation typically restores shoulder function after a common rotator cuff repair;however,it is unclear when to initiate physical therapy(PT)post-surgery.To understand effective start times,this study ...Background:Rehabilitation typically restores shoulder function after a common rotator cuff repair;however,it is unclear when to initiate physical therapy(PT)post-surgery.To understand effective start times,this study analyzed PT start times and their effect on shoulder function.The most effective shoulder outcomes were hypothesized to occur when PT started 0-4 weeks post-surgery.Methods:Data from 1002 patients who underwent rotator cuff repair were analyzed retrospectively from 52 outpatient clinics in the years of 2016-2021.The primary data of timings between surgery and the start of PT(0-2 weeks[0-14 days],2-4 weeks[15-28 days],4-6 weeks[29-42 days],and 6-14 weeks[43-100 days]),change in functional shoulder scores,number of PT visits utilized,and functional scores changed per visit were analyzed.Regression analyses of the impact of age,sex,payor source,and tear size were completed.Results:The change in functional scores and functional scores changed per visit are not affected by the initiation timing of PT postrotator cuff surgery,when controlling for baseline functional scores.This result is revealed despite initial functional scores being significantly different.Functional scores change per visit may have been affected by payor source(R^(2)=0.004,p≤0.010).PT start times may have been impacted by age(R^(2)=0.010,p=0.007),payor source(R^(2)=0.016,p=0.001),and tear size(R^(2)=0.007,p=0.026).Payor source may have influenced the number of PT visits(R^(2)=0.060,p<0.001).Conclusions:After rotator cuff surgery,patients should choose to complete rehabilitation to optimize shoulder function.However,the initiation timing of PT may not affect functional shoulder outcomes.展开更多
AIM:To investigate the optimal timing and therapeutic effects of cataract surgery in patients with moderate to severe thyroid-associated ophthalmopathy(TAO).METHODS:Data from TAO patients who underwent cataract surger...AIM:To investigate the optimal timing and therapeutic effects of cataract surgery in patients with moderate to severe thyroid-associated ophthalmopathy(TAO).METHODS:Data from TAO patients who underwent cataract surgery between 2014 and 2024 were analyzed.patients were categorized into two groups based on the hospital where their cataract surgery was performed:an external hospital surgery group and an in-house hospital surgery group.Patients in external hospital presenting with complications within six months postoperatively were assessed for clinical features,imaging,thyroid function,and outcomes.Patients who underwent surgery at West China Hospital were evaluated for clinical status,imaging,laboratory findings,and manifestations.RESULTS:In the external hospital group(n=31),common symptoms included eyelid swelling(64.52%)and diplopia(51.61%),with restricted eye movement in all patients.Most patients were in the active stage(87.10%)and exhibited various complications,such as dysthyroid optic neuropathy(DON)in 4 patients,misdiagnosis of glaucoma in 1 patient,and enucleation due to fungal infection in 1 patient.In the West China Hospital group(n=30),2 patients were in the active stage,and 28 were in the inactive stage.Postoperative visual acuity improved in 36 eyes,except for in 2 eyes with DON.Active TAO patients with mature cataracts had effective inflammation control and no complications at the 6-month follow-up.CONCLUSION:In patients with moderate to severe active TAO complicated by cataracts,delaying cataract surgery until 6mo of TAO control should be considered if cataracts are stable.Simultaneous anti-inflammatory treatment and cataract surgery should be performed for mature/hypermature cataracts,and TAO management should be continued after surgery.展开更多
High-performance positioning,navigation and timing(PNT)service is critical to the safe flight of low-altitude aircraft and the effective management of low altitude traffic.In low-altitude economic sce-narios,the speci...High-performance positioning,navigation and timing(PNT)service is critical to the safe flight of low-altitude aircraft and the effective management of low altitude traffic.In low-altitude economic sce-narios,the specificity of massive unmanned aerial ve-hicle(UAV)flights and the complexity of low-altitude airspace traffic management impose stringent demand on the high-continuity,high-accuracy,real-time,and high-security PNT service.However,the current PNT service,which primarily relies on Global Navigation Satellite System(GNSS),Micro-Electro-Mechanical System Inertial Navigation System(MEMS INS),etc.,is completely inadequate to support the future needs of low-altitude economic development.In order to bridge the huge gap between existing capability and future demand,a three-layer PNT architecture based on the collaboration of space-based,air-based and ground-based PNT systems is proposed for low-altitude econ-omy.The space-based layer consists of high,medium even possible low orbit GNSS constellations,such as BeiDou Navigation Satellite System(BDS),for high-precision,high-security absolute positioning and tim-ing.The air-based layer leverages inter-aircraft links for high-reliability dynamic relative positioning.The ground-based layer includes pseudolite network,as well as 5G-advanced(5G-A)/6G network,for more comprehensive coverage and real-time positioning.To this end,it is imperative to make breakthroughs in key technologies,from systems to airborne terminal,in-cluding but not limited to high-precision anti-jamming GNSS signal processing,high-reliability relative po-sitioning,real-time pseudolite positioning,and high-efficient multi-source information fusion at airborne terminal,etc.Due to the moderate redundancy,hetero-geneous mechanism,and multiple coverage from mul-tiple PNT systems,the proposed layered PNT archi-tecture possesses high robustness and resilient.Addi-tionally,the integration of INS,LiDAR and vision etc.perception technologies can significantly enhance the PNT capability.As a result,the proposed three-layer PNT architecture enable greater autonomy for low-altitude aircraft and intelligent traffic management for massive UAV operations,and promoting the safe and efficient development of the low-altitude economy.展开更多
Objective:Medical expulsive therapy(MET)is a suitable option for facilitating stone expulsion in patients with distal ureteral stones.This meta-analysis was conducted to compare efficacy and safety of monotherapy and ...Objective:Medical expulsive therapy(MET)is a suitable option for facilitating stone expulsion in patients with distal ureteral stones.This meta-analysis was conducted to compare efficacy and safety of monotherapy and combination therapy with tamsulosin,silodosin,and tadalafil on stone expulsion rate(SER)and stone expulsion time(SET),as well as their comparative safety,numbers of colic pain episodes,and need for analgesics.Methods:Randomized controlled trials were retrieved by searching PubMed,Scopus,and Web of Science up to November 27,2023.Hand-searching was also conducted in Google Scholar to find additional records.Papers in English that compared the safety and efficacy of at least two of the above agents in adults with distal ureteral stones≤10 mm were included.Results:In total,27 studies were identified(six studies through database searches and 21 through checking reference lists and hand-searching in Google Scholar).More than half of them(n=15,56%)were conducted in India.The SER significantly improved with silodosin compared with tamsulosin(odds ratio[OR]2.24,p<0.001),whereas the difference in SET was non-significant.Tadalafil achieved a significantly higher SER compared with tamsulosin(OR 1.42,p=0.042)without any difference in SET.Subgroup analysis of 5-and 10-mg doses of tadalafil showed no significant difference in SER or SET.We found no significant difference in need for analgesics(mean difference(MD−53.73,p=0.2)or the mean number of colic episodes(MD−0.42,p=0.060)between tadalafil and tamsulosin.SER or SET was not significantly different between silodosin and tadalafil.Tadalafil plus tamsulosin led to a significantly higher SER(OR 1.87,p<0.001)and SET(MD−2.99,p=0.002)compared with tamsulosin,without any significant difference in adverse effects.Conclusion:Compared with tamsulosin,SER significantly improved with silodosin,tadalafil,and the combination of tadalafil plus tamsulosin.Meanwhile,the difference in SET was only significant between tadalafil plus tamsulosin versus tamsulosin.It appears that tadalafil and silodosin have similar efficacy in SET and SER.All medical expulsive therapies had comparable safety.展开更多
文摘In order to synchronize the elements of the EAST Neutral Beam Injector （NBI） spatially located in several places, a distributed Timing System （TS） is developed in this paper. The timing system provides a clock reference for synchronization and an interlock protection of the EAST NBI system. It sends timing signals to field devices, controls the pulse widths of the timing sequences, and provides a sampling clock for the Data Acquisition System （DAS）. The timing system also generates analog waveforms to control power supplies and gas supplies according to the operator＇s configuration. The timing system is developed on a PXI （PCI eXtensions for Instrumentation） platform consisting of a LabVIEW workstation and a timing control terminal. The timing control terminal consists of a timing node and several control interface crates. Two timing nodes are configured in one beam line. Each node is responsible for the timing sequence, analog generation and feedback control for one ion source. The architecture and implementation of the timing system are presented in this paper.
基金supported by the Youth Innovation Promotion Association CAS(No.2016238)the National Natural Science Foundation of China(No.11305246)
文摘Large accelerator facilities require clocks and triggers with high accuracy to synchronize equipment and devices. A new femtosecond timing system was designed to meet the demands of new facilities. In this system, the radio-frequency signal is modulated in a continuous-wave laser carrier with frequency stabilization, and timing events are distributed in the same fiber. The phase drift is detected precisely, based on the principle of the Michelson interferometer. The phase drift is compensated with coarse and fine correctors afterward. We aim to realize the stable transmission of the RF signal and timing events for a long distance and duration, with the phase drift and additive jitter in femtoseconds. After the extension, the system will become a complete solution for the clock-and-trigger distribution of synchrotron radiation facilities, free-electron lasers, and other accelerators. The physics design, simulation analysis, and preliminary results are included in the paper.
文摘Volumetric efficiency and air charge estimation is one of the most demanding tasks in control of today's internal combustion engines.Specifically,using three-way catalytic converter involves strict control of the air/fuel ratio around the stoichiometric point and hence requires an accurate model for air charge estimation.However,high degrees of complexity and nonlinearity of the gas flow in the internal combustion engine make air charge estimation a challenging task.This is more obvious in engines with variable valve timing systems in which gas flow is more complex and depends on more functional variables.This results in models that are either quite empirical(such as look-up tables),not having interpretability and extrapolation capability,or physically based models which are not appropriate for onboard applications.Solving these problems,a novel semi-empirical model was proposed in this work which only needed engine speed,load,and valves timings for volumetric efficiency prediction.The accuracy and generalizability of the model is shown by its test on numerical and experimental data from three distinct engines.Normalized test errors are 0.0316,0.0152 and 0.24 for the three engines,respectively.Also the performance and complexity of the model were compared with neural networks as typical black box models.While the complexity of the model is less than half of the complexity of neural networks,and its computational cost is approximately 0.12 of that of neural networks and its prediction capability in the considered case studies is usually more.These results show the superiority of the proposed model over conventional black box models such as neural networks in terms of accuracy,generalizability and computational cost.
文摘A piece of equipment designed under a multi-disciplinary project in Shandong University of Science and Technology is described.The purpose is to indicate speech-time status to speakers in debates by presenting a three-light output The speech length may be programmed by the user with a combination of buttons and LCD display.The system is portable and microcontroller-based,using on-chip timers for accurate measurement of durations.
基金Hubei Province Top Medical Youth Talent Program,Wuhan Knowledge Innovation Special Basic Research Project,No.2023020201020558Clinical Research Project of Affiliated Hospital of Guangdong Medical University,No.LCYJ2021B004 and No.LCYJ2019B010Science and Technology Plan Project of Zhanjiang,No.2022A01191.
文摘BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therapeutic modality to improve healing outcomes in DFU management.AIM To evaluate the efficacy of UAWD in treating DFUs on wound closure rates,treatment duration,and quality of life outcomes.METHODS This systematic review and meta-analysis followed PRISMA guidelines,systematically searching PubMed,Embase,Web of Science,and the Cochrane Library with no date restrictions.Randomized controlled trials(RCTs)that evaluated the efficacy of UAWD in DFU treatment were included.Data were independently extracted by two reviewers,with discrepancies resolved through consensus or third-party consultation.The risk of bias was assessed using the Cochrane tool.χ2 and I2 statistics assessed heterogeneity,informing the use of fixed or random-effects models for meta-analysis,supplemented by sensitivity analysis and publication bias assessment through funnel plots and Egger's test.RESULTS From 1255 articles,seven RCTs met the inclusion criteria.The studies demonstrated that UAWD significantly reduced DFU healing time(standardized mean difference=-0.78,95%CI:-0.97 to-0.60,P<0.001)and increased healing rates(odds ratio=9.96,95%CI:5.99 to 16.56,P<0.001)compared to standard care.Sensitivity analysis confirmed the stability of these results,and no significant publication bias was detected.CONCLUSION UAWD is a promising adjunctive treatment for DFUs,significantly reducing healing times and increasing healing rates.These findings advocate for the integration of UAWD into standard DFU care protocols.
基金supported by Fund of State Key Laboratory of IPOC(BUPT)(No.IPOC2021ZT16),China.
文摘The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled phased array antenna system is a necessary trend for the future development of the phased array,and it is also a major focus and difficulty in the current research of integrated microwave photonics.This paper firstly introduces the basic principle and development history of optical true time delay phased array antenna system based on microwave photonics,and briefly introduces the main implementation methods and integration platform of optical true time delay.Then,the application and development prospect of optical true time delay technology in beam control of phased array antenna system are mainly presented.Finally,according to the current research progress,the possible research directions of integrated optically controlled phased array antenna systems in the future are proposed.
基金supported by the Basic Science Center Project of the National Natural Science Foundation of China(42388102)the National Natural Science Foundation of China(42174030)+2 种基金the Special Fund of Hubei Luojia Laboratory(220100020)the Major Science and Technology Program for Hubei Province(2022AAA002)the Fundamental Research Funds for the Central Universities of China(2042022dx0001 and 2042023kfyq01)。
文摘Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.
基金supported by the National Natural Science Foundation of China(12125505).
文摘The PICOSEC Micromegas(MM)is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure.It features a two-stage amplification process that leads to a significant deterioration of non-uniformity when scaling up to larger areas.Since the performance of gaseous detectors is highly dependent on the choice of working gas,optimizing the gas mixture offers a promising solution to improve the uniformity performance.This paper addresses these challenges through a combined approach of simulation based on Garfield++and experimental studies.The simulation investigates the properties of different mixing fractions of gas mixtures and their impact on detector performance,including gain uniformity and time resolution.To verify the simulation results,experimental tests were conducted using a multi-channel PICOSEC MM prototype with different gas mixtures.The experimental results are consistent with the findings of the simulation,indicating that a higher concentration of neon significantly improves the detector’s gain uniformity.Furthermore,the influence of gas mixtures on time resolution was explored as a critical performance indicator.The study presented in this paper offers valuable insights for improving uniformity in large-area PICOSEC MM detectors and optimizing overall performance.
文摘BACKGROUND Meniscal tears are one of the most common knee injuries.After the diagnosis of a meniscal tear has been made,there are several factors physicians use to guide clinical decision-making.The influence of time between injury and isolated meniscus repair on patient outcomes is not well described.Assessing this relationship is important as it may influence clinical decision-making and can add to the preoperative patient education process.We hypothesized that increasing the time from injury to meniscus surgery would worsen postoperative outcomes.AIM To investigate the current literature for data on the relationship between time between meniscus injury and repair on patient outcomes.METHODS PubMed,Academic Search Complete,MEDLINE,CINAHL,and SPORTDiscus were searched for studies published between January 1,1995 and July 13,2023 on isolated meniscus repair.Exclusion criteria included concomitant ligament surgery,incomplete outcomes or time to surgery data,and meniscectomies.Patient demographics,time to injury,and postoperative outcomes from each study were abstracted and analyzed.RESULTS Five studies met all inclusion and exclusion criteria.There were 204(121 male,83 female)patients included.Three of five(60%)studies determined that time between injury and surgery was not statistically significant for postoperative Lysholm scores(P=0.62),Tegner scores(P=0.46),failure rate(P=0.45,P=0.86),and International Knee Documentation Committee scores(P=0.65).Two of five(40%)studies found a statistically significant increase in Lysholm scores with shorter time to surgery(P=0.03)and a statistically significant association between progression of medial meniscus extrusion ratio(P=0.01)and increasing time to surgery.CONCLUSION Our results do not support the hypothesis that increased time from injury to isolated meniscus surgery worsens postoperative outcomes.Decision-making primarily based on injury interval is thus not recommended.
基金This work was supported by the High Energy Photon Source(HEPS)project,a major national science and technology infrastructure in Chinasupported by the fund of JSQ2018ZZ03 of the Key Laboratory of Particle Acceleration Physics&Technology,Institute of High Energy Physics,Chinese Academy of Sciences(CAS)and Youth Innovation Promotion Association,CAS(2019016).
文摘Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy synchrotron booster,a 6-GeV synchrotron storage ring(SR),and three e-beam transport lines for injection and extraction among accelerators.A global timing system(GTS)covers the timing needs for all accelerator,beamline,and experiment systems.The GTS is designed to coordinate the injection processes and various measurements and protections.Most systems require that the RMS jitter of the GTS signal is less than 30 ps,while the trigger jitters for the electron gun and SR injection and extraction kickers are less than 10 ps.Method The HEPS GTS is an event-based timing system based on MicroTCA.4 hardware architecture.The MicroTCA.4300 series products from the micro-research Finland Oy are implemented in the HEPS GTS system.Results and conclusions The RMS jitter,integrated from 1 Hz to 10 MHz,of the 166.6 MHz event clock is 5.489 ps.The RMS jitter of TTL outputs is less than 30 ps.This paper reports the design of the HEPS GTS,which satisfies all of the HEPS physics requirements for timing with preliminary test results shown.
文摘In this article,we discussed the article by Sohail et al,published in a recent issue of the World Journal of Gastrointestinal Endoscopy.This study highlights the benefits of performing cholecystectomy(CCY)during the same hospitalization for patients with acute cholangitis(AC)associated with gallstones.Specifically,same-admission CCY is associated with significantly lower 30-day readmission rates compared with interval CCY.Furthermore,it has been associated with reduced mortality rates and reduced recurrence of biliary symptoms.Despite these advantages,the procedure is chosen in only a minority of eligible patients.This gap between evidence and practice highlights the need for updated clinical guidelines and further research to optimize the timing of CCY in the management of AC.
基金supported by the National Natural Science Foundation of China(Grant No.52374043)the Southwest Oil&Gas Field Branch in PetroChina(Grant No.JS2023-115)。
文摘Over more than a decade of development,medium to deep shale gas reservoirs have faced rapid production declines,making sustained output challenging.To harness remaining reserves effectively,advanced fracturing techniques such as infill drilling are essential.This study develops a complex fracture network model for dual horizontal wells and a four-dimensional in-situ stress evolution model,grounded in elastic porous media theory.These models simulate and analyze the evolution of formation pore pressure and in-situ stress during production.The investigation focuses on the influence of infill well fracturing timing on fracture propagation patterns,individual well productivity,and the overall productivity of well clusters.The findings reveal that,at infill well locations,the maximum horizontal principal stress undergoes the most significant reduction,while changes in the minimum horizontal principal stress and vertical stress remain minimal.The horizontal stress surrounding the infill well may reorient,potentially transitioning the stress regime from strike-slip to normal faulting.Delays in infill well fracturing increase lateral fracture deflection and diminish fracture propagation between wells.Considering the stable production phase and cumulative gas output of the well group,the study identifies an optimal timing for infill fracturing.Notably,larger well spacing shifts the optimal timing to a later stage.
基金supported by the National Natural Science Foundation of China(Nos.52405088 and 92360306)the Postdoctoral Fellowship Program of CPSF,China(No.GZC20241446)+2 种基金the Natural Science Basic Research Program of Shaanxi,China(No.2024JC-YBMS-402)the Fundamental Research Funds for the Central Universities,CHD(No.300102254102)the Foundation of Beilin District,China(No.GX2455)。
文摘Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and noise subspaces,has been successfully applied for this purpose.However,conventional subspace selection methods relying on fixed thresholds are sensitive to variations in large eigenvalues.Furthermore,the complex disturbances during rotor operation and measurement complicate the identification of blade vibration characteristics.To overcome these challenges,this paper proposes Adaptive Subspace Separation(ASS)and Local Spectral Centroid(LSC)methods to improve the adaptability of subspace selection and the stability of frequency identification,respectively.The impacts of overestimating and underestimating the subspace dimensions on MUSIC's performance are derived mathematically.Simulation and experiments demonstrate the effectiveness of proposed approaches:ASS offers more accurate and stable subspace dimension selection and tracking,while LSC reduces the standard deviation of estimated frequencies by 30 percent.
基金The National Key Research and Development Program of China under contract No.2022YFE0136500the Scientific Research Fund of the Second Institute of Oceanography,Ministry of Natural Resources,under contract Nos JG2212 and JG2211+2 种基金the National Natural Science Foundation of China under contract Nos 42276255,41976228,and 42176227the National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”under contract Nos IRASCC 01-01-02 and IRASCC 02-02the China Scholarship Council under contract No.201704180017.
文摘The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of variability in the timing of seasonal sea ice retreat on the flux and composition of sinking particulate matter remains to be elucidated.In this study,we deployed sediment traps in Prydz Bay during the austral summers of 2019/2020 and 2020/2021,noting that sea ice melting occurred approximately one and a half months earlier in the former summer compared to the latter.We analyzed sediment trap data,which included total mass flux(TMF),particulate organic carbon(POC),biogenic silica(BSi),particulate inorganic carbon,and lithogenic particle(Litho)fluxes,as well as the stable isotopesδ^(13)C andδ^(15)N of particulate organic matter(POM).Additionally,we incorporated remote sensing data on sea ice concentration and chlorophyll a.This dramatic delay in sea ice melting timing could result in a significant increase in TMF,BSi and POC fluxes in the summer of 2020/2021 compared to 2019/2020.Elevated BSi fluxes and more ^(13)C-depleted POC in the austral summer of 2020/2021 suggest that the delayed melting of sea ice may have stimulated the productivity of centric diatoms.Furthermore,the higher BSi/POC ratio and more negativeδ^(15)N values of POM,along with a reduced presence of krill in the traps,indicate a diminished grazing pressure from zooplankton,which collectively enhanced the sedimentation efficiency of POC during the austral summer of 2020/2021.These findings highlight the critical role of sea ice melting timing in regulating productivity,flux and composition of sinking particulate matter in the Prydz Bay ecosystem,with significant implications for carbon cycling in polar oceans.
基金support from the Lawrence Livermore National Laboratory(Grant No.B622827)the National Science Foundation(Grant Nos.1824568,1810506,1741707,and 1829071)the Office of Naval Research(Grant No.N00014-16-1-2094).
文摘Laser frequency microcombs provide a series of equidistant,coherent frequency markers across a broad spectrum,enabling advancements in laser spectroscopy,dense optical communications,precision distance metrology,and astronomy.Here,we design and fabricate silicon nitride,dispersion-managed microresonators that effectively suppress avoided-mode crossings and achieve close-to-zero averaged dispersion.Both the stochastic noise and mode-locking dynamics of the resonator are numerically and experimentally investigated.First,we experimentally demonstrate thermally stabilized microcomb formation in the microresonator across different mode-locked states,showing negligible center frequency shifts and a broad frequency bandwidth.Next,we characterize the femtosecond timing jitter of the microcombs,supported by precise metrology of the timing phase and relative intensity noise.For the single-soliton state,we report a relative intensity noise of−153.2 dB∕Hz,close to the shot-noise limit,and a quantum-noise–limited timing jitter power spectral density of 0.4 as 2∕Hz at a 100 kHz offset frequency,measured using a self-heterodyne linear interferometer.In addition,we achieve an integrated timing jitter of 1.7 fs±0.07 fs,measured from 10 kHz to 1 MHz.Measuring and understanding these fundamental noise parameters in high clock rate frequency microcombs is critical for advancing soliton physics and enabling new applications in precision metrology.
基金Supported by the National Key Research and Development Program,China,No.2022YFC2503603.
文摘BACKGROUND Bile duct leaks(BDLs)are serious postsurgical adverse events.Typically,conservative management with ab-dominal drainage is the initial treatment option.However,prolonged abdominal drainage without improvement can lead to biliary stricture and delay the optimal timing of endoscopic retrograde cholangiopancreatography(ERCP).AIM To identify the optimal timing for ERCP and the period during which clinical observation with conservative management is acceptable,balancing ERCP success and the risk of biliary strictures.METHODS We conducted a multicenter retrospective study involving 448 patients with BDLs between November 2002 and November 2022.The patients were divided into four groups based on the timing of ERCP:3 days,7 days,14 days,and 21 days.The primary outcome was clinical success,defined as the resolution of BDL and related symptoms within 6 months without additional percutaneous drainage,surgery,or death.The secondary outcome was incidence of biliary strictures.Univariate and multivariate logistic regression analyses were performed to identify factors associated with ERCP success and biliary stricture occurrence.RESULTS In a cohort of 448 consecutive patients diagnosed with BDLs,354 were excluded,leaving 94 patients who underwent ERCP.Clinical success was achieved in 84%of cases(79/94),with a median ERCP timing of 20 days(9.5-35.3 days).Biliary strictures were identified in 29(30.9%)patients.Performing ERCP within 3 weeks,compared to after 3 weeks,was associated with higher success rates[92.0%(46/50)vs 75.0%(33/44),P=0.032]and a lower incidence of biliary stricture incidence[18.0%(9/50)vs 45.5%(20/44),P=0.005].Subsequent multivariate analysis confirmed the association with higher success rates(odds ratio=4.168,P=0.045)and lower biliary stricture rates(odds ratio=0.256,P=0.007).CONCLUSION Performing ERCP for BDLs within 3 weeks may be associated with a higher success rate and a lower biliary stricture rate.If patients with BDLs do not respond to conservative treatment,ERCP is suggested to be performed within 3 weeks.
文摘Background:Rehabilitation typically restores shoulder function after a common rotator cuff repair;however,it is unclear when to initiate physical therapy(PT)post-surgery.To understand effective start times,this study analyzed PT start times and their effect on shoulder function.The most effective shoulder outcomes were hypothesized to occur when PT started 0-4 weeks post-surgery.Methods:Data from 1002 patients who underwent rotator cuff repair were analyzed retrospectively from 52 outpatient clinics in the years of 2016-2021.The primary data of timings between surgery and the start of PT(0-2 weeks[0-14 days],2-4 weeks[15-28 days],4-6 weeks[29-42 days],and 6-14 weeks[43-100 days]),change in functional shoulder scores,number of PT visits utilized,and functional scores changed per visit were analyzed.Regression analyses of the impact of age,sex,payor source,and tear size were completed.Results:The change in functional scores and functional scores changed per visit are not affected by the initiation timing of PT postrotator cuff surgery,when controlling for baseline functional scores.This result is revealed despite initial functional scores being significantly different.Functional scores change per visit may have been affected by payor source(R^(2)=0.004,p≤0.010).PT start times may have been impacted by age(R^(2)=0.010,p=0.007),payor source(R^(2)=0.016,p=0.001),and tear size(R^(2)=0.007,p=0.026).Payor source may have influenced the number of PT visits(R^(2)=0.060,p<0.001).Conclusions:After rotator cuff surgery,patients should choose to complete rehabilitation to optimize shoulder function.However,the initiation timing of PT may not affect functional shoulder outcomes.
基金Supported by Sichuan Science and Technology Program(No.2022JDKP0010).
文摘AIM:To investigate the optimal timing and therapeutic effects of cataract surgery in patients with moderate to severe thyroid-associated ophthalmopathy(TAO).METHODS:Data from TAO patients who underwent cataract surgery between 2014 and 2024 were analyzed.patients were categorized into two groups based on the hospital where their cataract surgery was performed:an external hospital surgery group and an in-house hospital surgery group.Patients in external hospital presenting with complications within six months postoperatively were assessed for clinical features,imaging,thyroid function,and outcomes.Patients who underwent surgery at West China Hospital were evaluated for clinical status,imaging,laboratory findings,and manifestations.RESULTS:In the external hospital group(n=31),common symptoms included eyelid swelling(64.52%)and diplopia(51.61%),with restricted eye movement in all patients.Most patients were in the active stage(87.10%)and exhibited various complications,such as dysthyroid optic neuropathy(DON)in 4 patients,misdiagnosis of glaucoma in 1 patient,and enucleation due to fungal infection in 1 patient.In the West China Hospital group(n=30),2 patients were in the active stage,and 28 were in the inactive stage.Postoperative visual acuity improved in 36 eyes,except for in 2 eyes with DON.Active TAO patients with mature cataracts had effective inflammation control and no complications at the 6-month follow-up.CONCLUSION:In patients with moderate to severe active TAO complicated by cataracts,delaying cataract surgery until 6mo of TAO control should be considered if cataracts are stable.Simultaneous anti-inflammatory treatment and cataract surgery should be performed for mature/hypermature cataracts,and TAO management should be continued after surgery.
基金supported in part by the National Key R&D Program of China under Grant 2021YFA0716600 and 2024ZD1300100in part by the National Natural Science Foundation of China under Grant 42274018,42425401,62371029,62271285 and U2233217.
文摘High-performance positioning,navigation and timing(PNT)service is critical to the safe flight of low-altitude aircraft and the effective management of low altitude traffic.In low-altitude economic sce-narios,the specificity of massive unmanned aerial ve-hicle(UAV)flights and the complexity of low-altitude airspace traffic management impose stringent demand on the high-continuity,high-accuracy,real-time,and high-security PNT service.However,the current PNT service,which primarily relies on Global Navigation Satellite System(GNSS),Micro-Electro-Mechanical System Inertial Navigation System(MEMS INS),etc.,is completely inadequate to support the future needs of low-altitude economic development.In order to bridge the huge gap between existing capability and future demand,a three-layer PNT architecture based on the collaboration of space-based,air-based and ground-based PNT systems is proposed for low-altitude econ-omy.The space-based layer consists of high,medium even possible low orbit GNSS constellations,such as BeiDou Navigation Satellite System(BDS),for high-precision,high-security absolute positioning and tim-ing.The air-based layer leverages inter-aircraft links for high-reliability dynamic relative positioning.The ground-based layer includes pseudolite network,as well as 5G-advanced(5G-A)/6G network,for more comprehensive coverage and real-time positioning.To this end,it is imperative to make breakthroughs in key technologies,from systems to airborne terminal,in-cluding but not limited to high-precision anti-jamming GNSS signal processing,high-reliability relative po-sitioning,real-time pseudolite positioning,and high-efficient multi-source information fusion at airborne terminal,etc.Due to the moderate redundancy,hetero-geneous mechanism,and multiple coverage from mul-tiple PNT systems,the proposed layered PNT archi-tecture possesses high robustness and resilient.Addi-tionally,the integration of INS,LiDAR and vision etc.perception technologies can significantly enhance the PNT capability.As a result,the proposed three-layer PNT architecture enable greater autonomy for low-altitude aircraft and intelligent traffic management for massive UAV operations,and promoting the safe and efficient development of the low-altitude economy.
文摘Objective:Medical expulsive therapy(MET)is a suitable option for facilitating stone expulsion in patients with distal ureteral stones.This meta-analysis was conducted to compare efficacy and safety of monotherapy and combination therapy with tamsulosin,silodosin,and tadalafil on stone expulsion rate(SER)and stone expulsion time(SET),as well as their comparative safety,numbers of colic pain episodes,and need for analgesics.Methods:Randomized controlled trials were retrieved by searching PubMed,Scopus,and Web of Science up to November 27,2023.Hand-searching was also conducted in Google Scholar to find additional records.Papers in English that compared the safety and efficacy of at least two of the above agents in adults with distal ureteral stones≤10 mm were included.Results:In total,27 studies were identified(six studies through database searches and 21 through checking reference lists and hand-searching in Google Scholar).More than half of them(n=15,56%)were conducted in India.The SER significantly improved with silodosin compared with tamsulosin(odds ratio[OR]2.24,p<0.001),whereas the difference in SET was non-significant.Tadalafil achieved a significantly higher SER compared with tamsulosin(OR 1.42,p=0.042)without any difference in SET.Subgroup analysis of 5-and 10-mg doses of tadalafil showed no significant difference in SER or SET.We found no significant difference in need for analgesics(mean difference(MD−53.73,p=0.2)or the mean number of colic episodes(MD−0.42,p=0.060)between tadalafil and tamsulosin.SER or SET was not significantly different between silodosin and tadalafil.Tadalafil plus tamsulosin led to a significantly higher SER(OR 1.87,p<0.001)and SET(MD−2.99,p=0.002)compared with tamsulosin,without any significant difference in adverse effects.Conclusion:Compared with tamsulosin,SER significantly improved with silodosin,tadalafil,and the combination of tadalafil plus tamsulosin.Meanwhile,the difference in SET was only significant between tadalafil plus tamsulosin versus tamsulosin.It appears that tadalafil and silodosin have similar efficacy in SET and SER.All medical expulsive therapies had comparable safety.
