BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in th...BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in the pelvis,hips,and knees,the inverse relationship concerning knee pathology undergoing total knee arthroplasty(TKA)has been examined by a limited number of studies,yielding inconclusive results.AIM To generate evidence of the effect of TKA on the SSA from existing literature.METHODS Databases like PubMed,EMBASE,and Scopus were used to identify articles related to the“knee spine syndrome”phenomenon using a combination of subject terms and keywords such as“spinopelvic parameters”,“sagittal spinal balance”,and“total knee arthroplasty”were used with appropriate Boolean operators.Studies measuring the SSA following TKA were included,and research was conducted as per preferred reporting items for systematic review and metaanalysis guidelines.RESULTS A total of 475 participants had undergone TKA,and six studies measuring SSA were analysed.Following TKA,pelvic tilt was the only parameter that showed significant changes,while lumbar lordosis(LL),pelvic incidence,and sacral slope were non-significant,as evident from the forest plots.CONCLUSION The body's sagittal alignment is a complex balance between pelvic,spine,and lower extremity parameters.TKA,while having the potential to correct the flexion contracture,can also correct it.Still,the primary SSA for spinal pathology,i.e.,LL,may not be corrected in patients with co-existent spinal degenerative disease.展开更多
BACKGROUND Demineralized bone matrix(DBM)is a commonly utilized allogenic bone graft substitute to promote osseous union.However,little is known regarding outcomes following DBM utilization in foot and ankle surgical ...BACKGROUND Demineralized bone matrix(DBM)is a commonly utilized allogenic bone graft substitute to promote osseous union.However,little is known regarding outcomes following DBM utilization in foot and ankle surgical procedures.AIM To evaluate the clinical and radiographic outcomes following DBM as a biological adjunct in foot and ankle surgical procedures.METHODS During May 2023,the PubMed,EMBASE and Cochrane library databases were systematically reviewed to identify clinical studies examining outcomes following DBM for the management of various foot and ankle pathologies.Data regarding study characteristics,patient demographics,subjective clinical outcomes,radiological outcomes,complications,and failure rates were extracted and analyzed.In addition,the level of evidence(LOE)and quality of evidence(QOE)for each individual study was also assessed.Thirteen studies were included in this review.RESULTS In total,363 patients(397 ankles and feet)received DBM as part of their surgical procedure at a weighted mean follow-up time of 20.8±9.2 months.The most common procedure performed was ankle arthrodesis in 94 patients(25.9%).Other procedures performed included hindfoot fusion,1st metatarsophalangeal joint arthrodesis,5th metatarsal intramedullary screw fixation,hallux valgus correction,osteochondral lesion of the talus repair and unicameral talar cyst resection.The osseous union rate in the ankle and hindfoot arthrodesis cohort,base of the 5th metatarsal cohort,and calcaneal fracture cohort was 85.6%,100%,and 100%,respectively.The weighted mean visual analog scale in the osteochondral lesions of the talus cohort improved from a pre-operative score of 7.6±0.1 to a post-operative score of 0.4±0.1.The overall complication rate was 27.2%,the most common of which was non-union(8.8%).There were 43 failures(10.8%)all of which warranted a further surgical procedure.CONCLUSION This current systematic review demonstrated that the utilization of DBM in foot and ankle surgical procedures led to satisfactory osseous union rates with favorable wound complication rates.Excellent outcomes were observed in patients undergoing fracture fixation augmented with DBM,with mixed evidence supporting the routine use of DBM in fusion procedures of the ankle and hindfoot.However,the low LOE together with the low QOE and significant heterogeneity between the included studies reinforces the need for randomized control trials to be conducted to identify the optimal role of DBM in the setting of foot and ankle surgical procedures.展开更多
BACKGROUND Peripheral artery disease(PAD)affects millions globally,with a 5.6%prevalence in 2015 impacting 236 million adults,rising above 10%in those over 60 due to factors like diabetes and smoking.Post-revasculariz...BACKGROUND Peripheral artery disease(PAD)affects millions globally,with a 5.6%prevalence in 2015 impacting 236 million adults,rising above 10%in those over 60 due to factors like diabetes and smoking.Post-revascularization,single antiplatelet therapy(SAPT)is standard,but dual antiplatelet therapy(DAPT)may improve outcomes,though duration and bleeding risks are unclear.The 2024 American College of Cardiology/American Heart Association guidelines endorse short-term DAPT,yet evidence gaps remain in comparative efficacy and safety.We hypothesized that DAPT reduces cardiovascular events and reinterventions vs SAPT without significantly elevating bleeding in PAD patients’post-lower extremity revascularization.AIM To evaluate the efficacy and safety of DAPT vs SAPT in PAD patients’post-revascularization.METHODS This systematic review and meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,searching PubMed,EMBASE,and ScienceDirect up to July 2025.Included were randomized controlled trials(RCTs)and cohort studies from various global settings(e.g.,hospitals,tertiary care)comparing DAPT(aspirin plus P2Y12 inhibitor for>1 month)to SAPT in symptomatic PAD patients undergoing endovascular or surgical revascularization(n up to 28244 participants selected via eligibility criteria).Data were pooled using random-effects models for risk ratio(RR)with 95%CI;heterogeneity was assessed via the I²statistic.Quality appraisal used Risk of Bias in Non-randomized Studies of Interventions for cohorts and Risk of Bias 2.0 for RCTs;certainty was evaluated via Grading of Recommendations Assessment,Development and Evaluation(GRADE).RESULTS Twelve studies(3 RCTs,9 cohorts,conducted 2010–2025 with follow-ups of 6 months to 5 years)were included.DAPT showed no significant difference but a trend toward reduced all-cause mortality(RR:0.52,95%CI:0.27–1.01,P=0.05,DAPT of 298/9545 events vs SAPT of 165/566 events)or stroke(RR:0.72,95%CI:0.30–1.72,P=0.46,DAPT of 16/3729 events vs SAPT of 41/7673 events)vs SAPT.DAPT significantly reduced cardiac mortality(RR:0.46,95%CI:0.27–0.80,P=0.006,DAPT of 78/2903 events vs SAPT of 171/1465 events,risk difference:-5.4%),myocardial infarction(RR:0.82,95%CI:0.71–0.94,P=0.004,DAPT of 233/7704 events vs SAPT of 262/9130 events,risk difference:-1.8%),and major reintervention(RR:0.58,95%CI:0.35–0.98,P=0.04,DAPT of 803/205 events vs SAPT of 1197/4 events,risk difference:-42%).Bleeding showed no difference(RR:1.12,95%CI:0.42–3.03,P=0.82,DAPT of 195/2775 events vs SAPT of 202/8234 events).Heterogeneity was high(I^(2)=59%–97%).Quality revealed moderate to serious bias in cohorts and some concerns in RCTs;GRADE certainty moderate for cardiac mortality,myocardial infarction,reintervention,low for others due to inconsistency and imprecision.CONCLUSION DAPT reduces cardiac mortality,myocardial infarction,and major reintervention risks compared to SAPT in PAD post-revascularization without apparent bleeding increase,though limited by heterogeneity and low certainty for some outcomes.展开更多
Sixth Generation(6G)mobile communication networks will involve sensing as a new function,with the overwhelming trend of Integrated Sensing And Communications(ISAC).Although expanding the serving range of the networks,...Sixth Generation(6G)mobile communication networks will involve sensing as a new function,with the overwhelming trend of Integrated Sensing And Communications(ISAC).Although expanding the serving range of the networks,there exists performance trade-offbetween communication and sensing,in that they have competitions on the physical resources.Different resource allocation schemes will result in different sensing and communication performance,thus influencing the system’s overall performance.Therefore,how to model the system’s overall performance,and how to optimize it are key issues for ISAC.Relying on the large-scale deployment of the networks,cooperative ISAC has the advantages of wider coverage,more robust performance and good compatibility of multiple monostatic and multistatic sensing,compared to the non-cooperative ISAC.How to capture the performance gain of cooperation is a key issue for cooperative ISAC.To address the aforementioned vital problems,in this paper,we analyze the sensing accuracy gain,propose a unified ISAC performance evaluation framework and design several optimization methods in cooperative ISAC systems.The cooperative sensing accuracy gain is theoretically analyzed via Cramér Rao lower bound.The unified ISAC performance evaluation model is established by converting the communication mutual information to the effective minimum mean squared error.To optimize the unified ISAC performance,we design the optimization algorithms considering three factors:base stations’working modes,power allocation schemes and waveform design.Through simulations,we show the performance gain of the cooperative ISAC system and the effectiveness of the proposed optimization methods.展开更多
According to the complex differential accumulation history of deep marine oil and gas in superimposed basins,the Lower Paleozoic petroleum system in Tahe Oilfield of Tarim Basin is selected as a typical case,and the p...According to the complex differential accumulation history of deep marine oil and gas in superimposed basins,the Lower Paleozoic petroleum system in Tahe Oilfield of Tarim Basin is selected as a typical case,and the process of hydrocarbon generation and expulsion,migration and accumulation,adjustment and transformation of deep oil and gas is restored by means of reservoine-forming dynamics simulation.The thermal evolution history of the Lower Cambrian source rocks in Tahe Oilfield reflects the obvious differences in hydrocarbon generation and expulsion process and intensity in different tectonic zones,which is the main reason controlling the differences in deep oil and gas phases.The complex transport system composed of strike-slip fault and unconformity,etc.controlled early migration and accumulation and late adjustment of deep oil and gas,while the Middle Cambrian gypsum-salt rock in inner carbonate platform prevented vertical migration and accumulation of deep oil and gas,resulting in an obvious"fault-controlled"feature of deep oil and gas,in which the low potential area superimposed by the NE-strike-slip fault zone and deep oil and gas migration was conducive to accumulation,and it is mainly beaded along the strike-slip fault zone in the northeast direction.The dynamic simulation of reservoir formation reveals that the spatio-temporal configuration of"source-fault-fracture-gypsum-preservation"controls the differential accumulation of deep oil and gas in Tahe Oilfield.The Ordovician has experienced the accumulation history of multiple periods of charging,vertical migration and accumulation,and lateral adjustment and transformation,and deep oil and gas have always been in the dynamic equilibrium of migration,accumulation and escape.The statistics of residual oil and gas show that the deep stratum of Tahe Oilfield still has exploration and development potential in the Ordovician Yingshan Formation and Penglaiba Formation,and the Middle and Upper Cambrian ultra-deep stratum has a certain oil and gas resource prospect.This study provides a reference for the dynamic quantitative evaluation of deep oil and gas in the Tarim Basin,and also provides a reference for the study of reservoir formation and evolution in carbonate reservoir of paleo-craton basin.展开更多
The resource allocation technique is of great significance in achieving frequency spectrum coexistence in Joint Radar-Communication(JRC) systems, by which the problem of radio frequency spectrum congestion can be well...The resource allocation technique is of great significance in achieving frequency spectrum coexistence in Joint Radar-Communication(JRC) systems, by which the problem of radio frequency spectrum congestion can be well alleviated. A Robust Joint Frequency Spectrum and Power Allocation(RJFSPA) strategy is proposed for the Coexisting Radar and Communication(CRC)system. Specifically, we consider the uncertainty of target Radar Cross Section(RCS) and communication channel gain to formulate a bi-objective optimization model. The joint probabilities that the Cramér-Rao Lower Bound(CRLB) of each target satisfying the localization accuracy threshold and the Communication Data Ratio(CDR) of each user satisfying the communication threshold are simultaneously maximized, under the constraint of the total power budget. A Three-Stage Alternating Optimization Method(TSAOM) is proposed to obtain the Best-Known Pareto Subset(BKPS) of this problem, where the frequency spectrum, radar power, and communicator power are allocated using the greedy search and standard convex optimization methods, respectively. Simulation results confirm the effectiveness of the proposed RJFSPA strategy, compared with the resource allocation methods in a uniform manner and that ignores the uncertainties. The efficiency of the TSAOM is also verified by the comparison with the exhaustive search-based method.展开更多
We introduce and study the relation between Pesin-Pitskel topological pressure on an arbitrary subset and measure theoretic pressure of Borel probability measure for nonautonomous dynamical systems,which is an extensi...We introduce and study the relation between Pesin-Pitskel topological pressure on an arbitrary subset and measure theoretic pressure of Borel probability measure for nonautonomous dynamical systems,which is an extension of the classical definition of Bowen topological entropy.We show that the Pesin-Pitskel topological pressure can be determined by the local pressures of measures in nonautonomous case and establish a variational principle for Pesin-Pitskel topological pressure on compact subsets in the context of nonautonomous dynamical systems.展开更多
Objective Venous thromboembolism is a highly prevalent condition after polytrauma,and recognized as an important factor contributing to poor prognosis.The aim of this study was to investigate the risk factors for lowe...Objective Venous thromboembolism is a highly prevalent condition after polytrauma,and recognized as an important factor contributing to poor prognosis.The aim of this study was to investigate the risk factors for lower extremity deep venous thrombosis(LEDVT)in a severely traumatized population and to evaluate their predictive value for LEDVT.Methods This was a retrospective,single-center observational study.All subjects were severely traumatized patients who were admitted to the Traumatic Intensive Care Unit from January 2021 to May 2024.Based on Doppler ultrasound findings of both lower extremities from the time of injury to 30 days post-injury,patients who developed LEDVT were enrolled in the LEDVT group,and those who did not develop LEDVT were enrolled in the NLEDVT group.Demographic,clinical,and laboratory data were collected upon admission.Multivariable logistic regression analysis was performed to identify risk factors for LEDVT.Receiver operating characteristic(ROC)curve was used to evaluate the overall fit of the final model.Results There were 56 patients enrolled in the LEDVT group and 81 patients in the NLEDVT group.Age,Aggregate Index of Systemic Inflammation(AISI),Systemic Inflammation Response Index(SIRI),ICU length of stay,and albumin were identified as independent risk factors for LEDVT(all P<0.05).The area under their ROC curves were 0.604,0.657,0.694,0.668,and 0.405,respectively.Combined model for early clinical prediction of LEDVT in severely traumatized patients by age,SIRI,AISI,and albumin resulted in an area under the ROC curve of 0.805(95%CI:0.73-0.88,SE=0.037).Conclusion The combination of age,SIRI,AISI,and albumin has a predictive value for LEDVT in severely traumatized patients.展开更多
Tobacco polysaccharides were extracted by hot water extraction,and purified and separated using DEAE-52 cellulose chromatography columns,and three purified polysaccharide fractions,YCT-1,YCT-2,and YCT-3,were finally o...Tobacco polysaccharides were extracted by hot water extraction,and purified and separated using DEAE-52 cellulose chromatography columns,and three purified polysaccharide fractions,YCT-1,YCT-2,and YCT-3,were finally obtained.The physicochemical properties of the three fractions were analyzed by ultraviolet spectroscopy,high-performance liquid chromatography and high-performance gel chromatography.The in vitro antioxidant activity of tobacco polysaccharides was compared among different fractions by using DPPH radical,hydroxyl radical scavenging assay and potassium ferricyanide method.The in vitro hypoglycemic activity was compared usingα-amylase andα-glucosidase activity inhibition assay.And the in vitro hypolipidemic activity were investigated by using pancreatic lipase activity inhibition assay and HepG-2 intracellular lipid accumulation assay.All the results showed that the constituent monosaccharides of the three tobacco polysaccharide fractions were similar,but the molar percentages of each monosaccharide were different.The average molecular weights of the three components were 27,727 Da,27,587 Da,and 66,517 Da,respectively,and the scavenging activities on DPPH radicals and hydroxyl radicals were at a high level with good quantitative-effect relationships.The reducing power were much lower than that of the positive control VC,and the three polysaccharide fractions had a weak inhibitory ability onα-amylase activity,but showed excellent inhibitory ability onα-glucosidase and pancreatic lipase activity.In addition,the results of cellular experiments showed that all three fractions were able to inhibit lipid over-accumulation in HepG-2 cells by increasing the mRNA expression levels of PPAR-α,CPT-1A,and CYP7A1 genes,and the tobacco polysaccharide YCT-3 showed the best effect.The mechanism by which YCT-3 ameliorated the over-accumulation of intracellular lipids in HepG-2 cells was found to be related to its influence on the expression of miR-155-3p and miR-17-3p in the exosomes of HepG-2 cells.展开更多
In this article, an unknown system dynamics estimator-based impedance control method is proposed for the lower limb exoskeleton to stimulate the tracking flexibility with the terminal target position when suffering pa...In this article, an unknown system dynamics estimator-based impedance control method is proposed for the lower limb exoskeleton to stimulate the tracking flexibility with the terminal target position when suffering parametric inaccuracies and unexpected disturbances. To reinforce the robust performance, via constructing the filtering operation-based dynamic relation, i.e., invariant manifold, the unknown system dynamics estimators are employed to maintain the accurate perturbation identification in both the hip and knee subsystem. Besides, a funnel control technique is designed to govern the convergence process within a minor overshoot and a higher steady-state precision. Meanwhile, an interactive complaint result can be obtained with the aid of the impedance control, where the prescribed terminal trajectory can be adjusted into the interaction variable-based target position by the force–position mapping, revealing the dynamic influence between the impedance coefficient (stiffness and damping) and the adjusted position magnitude. A sufficient stability analysis verifies the ultimately uniformly bounded results of all the error signals, and even the angle errors can be regulated within the predefined funnel boundary in the whole convergence. Finally, some simulations are provided to demonstrate the validity and superiority including the enhanced interaction flexibility and robustness.展开更多
In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with ...In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with lateral recess stenosis.The impact of spinal pain-related disability extends significantly,causing substantial human suffering and medical costs.Each county has its preferred treatment strategies for spinal pain.Here,we explore the lower back pain(LBP)treatment algorithm recommended in France.The treatment algorithm for LBP recommended by the French National Authority for Health emphasizes early patient activity and minimal medication use.It encourages the continuation of daily activities,limits excessive medication and spinal injections,and incorporates psychological assessments and non-pharmacological therapies for chronic cases.However,the algorithm may not aggressively address acute pain in the early stages,potentially delaying relief and increasing the risk of chronicity.Additionally,the recommended infiltrations primarily involve caudal epidural steroid injections,with limited consideration for other injection procedures,such as transforaminal or interlaminar epidural steroid injections.The fixed follow-up timeline may not accommodate patients who do not respond to initial treatment or experience intense pain,potentially delaying the exploration of alternative therapies.Despite these limitations,understanding the strengths and weaknesses of the French approach could inform adaptations in LBP treatment strategies globally,potentially enhancing patient outcomes and satisfaction across diverse healthcare systems.展开更多
Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin,a new understanding of the source rocks,reservoir conditions,and source-reservoir-cap rock combinations of the ...Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin,a new understanding of the source rocks,reservoir conditions,and source-reservoir-cap rock combinations of the Jurassic Shuixigou Group in the Taibei Sag is established using the concept of the whole petroleum system,and the coal-measure whole petroleum system is analyzed thoroughly.The results are obtained in three aspects.First,the coal-measure source rocks of the Badaowan Formation and Xishanyao Formation and the argillaceous source rocks of the Sangonghe Formation in the Shuixigou Group exhibit the characteristics of long-term hydrocarbon generation,multiple hydrocarbon generation peaks,and simultaneous oil and gas generation,providing sufficient oil and gas sources for the whole petroleum system in the Jurassic coal-bearing basin.Second,multi-phase shallow braided river delta–shallow lacustrine deposits contribute multiple types of reservoirs,e.g.sandstone,tight sandstone,shale and coal rock,in slope and depression areas,providing effective storage space for the petroleum reservoir formation in coal-measure strata.Third,three phases of hydrocarbon charging and structural evolution,as well as effective configuration of multiple types of reservoirs,result in the sequential accumulation of conventional-unconventional hydrocarbons.From high structural positions to depression,there are conventional structural and structural-lithological reservoirs far from the source,low-saturation structural-lithological reservoirs near the source,and tight sandstone gas,coal rock gas and shale oil accumulations within the source.Typically,the tight sandstone gas and coal rock gas are the key options for further exploration,and the shale oil and gas in the depression area is worth of more attention.The new understanding of the whole petroleum system in the coal measures could further enrich and improve the geological theory of the whole petroleum system,and provide new ideas for the overall exploration of oil and gas resources in the Tuha Basin.展开更多
As an important parameter in the single airborne passive locating system, the rate of phase difference change contains range information of the radio emitter. Taking single carrier sine pulse signals as an example, th...As an important parameter in the single airborne passive locating system, the rate of phase difference change contains range information of the radio emitter. Taking single carrier sine pulse signals as an example, this article illustrates the principle of passive location through measurement of rates of phase difference change and analyzes the structure of measurement errors. On the basis of the Cramér-Rao lower bound (CRLB), an algorithm associated with time-chips is proposed to determine the rates of pha...展开更多
Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synt...Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models.展开更多
Objective This study aims to analyze the burden of lower respiratory infections in Chinese elderly people aged 70 and above.Methods This study utilized Global Burden of Disease(GBD)1990-2050 prediction data to analyze...Objective This study aims to analyze the burden of lower respiratory infections in Chinese elderly people aged 70 and above.Methods This study utilized Global Burden of Disease(GBD)1990-2050 prediction data to analyze changes in mortality rates and disability-adjusted life year(DALY)rates for lower respiratory infections in the elderly population(aged 70 and above)in China from 1990 to 2050.It also discusses future trends in the burden of lower respiratory infections(LRI)in China under different scenarios.Results According to GBD predictions,the burden of lower respiratory infections in the elderly aged 70 years and above in China is lower than the global average.The burden has been decreasing from 1990 to 2020,but is projected to increase from 2020 to 2050.Scenario-based predictions suggest that,under scenarios involving improvements in nutrition and vaccination,the burden of lower respiratory infections in the elderly in China is expected to be the lowest in 2050.Conclusion This study indicates that the burden of lower respiratory infections in elderly people aged 70 years and above in China remains a significant public health issue and may worsen.The government should consider strengthening the preventive measures and management strategies for respiratory infections in the elderly population.展开更多
BACKGROUND Most patients who were included in previous studies on achalasia had increased lower esophageal sphincter(LES)pressure.Peroral endoscopic myotomy(POEM)has been confirmed to be effective at relieving the cli...BACKGROUND Most patients who were included in previous studies on achalasia had increased lower esophageal sphincter(LES)pressure.Peroral endoscopic myotomy(POEM)has been confirmed to be effective at relieving the clinical symptoms of achalasia associated with increased LES pressure.AIM To identify the safety and efficacy of POEM for patients with normal LES integrated relaxation pressure(LES-IRP).METHODS The clinical data of patients who underwent POEM successfully in The First Medical Center of Chinese PLA General Hospital were retrospectively analyzed.A total of 481 patients who underwent preoperative high-resolution manometry(HRM)at our hospital were ultimately included in this research.According to the HRM results,the patients were divided into two groups:71 patients were included in the normal LES-IRP group(LES-IRP<15 mmHg)and 410 patients were included in the increased LES-IRP group(LES-IRP≥15 mmHg).Clinical characteristics,procedure-related parameters,adverse events,and outcomes were compared between the two groups to evaluate the safety and efficacy of POEM for patients with normal LES-IRP.RESULTS Among the 481 patients included in our study,209 were males and 272 were females,with a mean age of 44.2 years.All patients underwent POEM without severe adverse events.The median pre-treatment Eckardt scores of the normal LES-IRP and increased LES-IRP groups were 7.0 and 7.0(P=0.132),respectively,decreasing to 1.0 and 1.0 post-treatment(P=0.572).The clinical success rate of the normal LES-IRP group was 87.3%(62/71),and that of the increased LES-IRP group was 91.2%(374/410)(P=0.298).Reflux symptoms were measured by the GerdQ questionnaire,and the percentages of patients with GerdQ scores≥9 in the normal LES-IRP and increased LES-IRP groups were 8.5%and 10.7%,respectively(P=0.711).After matching,the rates of clinical success and the rates of GerdQ score≥9 were not significantly different between the two groups.CONCLUSION Our results suggest that POEM is safe and effective for achalasia and patients with normal LES-IRP.In addition,in patients with normal LES-IRP,compared with those with increased LES-IRP,POEM was not associated with a greater incidence of reflux symptoms.展开更多
Based on the experimental results of casting thin section,low temperature nitrogen adsorption,high pressure mercury injection,nuclear magnetic resonance T2 spectrum,contact angle and oil-water interfacial tension,the ...Based on the experimental results of casting thin section,low temperature nitrogen adsorption,high pressure mercury injection,nuclear magnetic resonance T2 spectrum,contact angle and oil-water interfacial tension,the relationship between pore throat structure and crude oil mobility characteristics of full particle sequence reservoirs in the Lower Permian Fengcheng Formation of Mahu Sag,Junggar Basin,are revealed.(1)With the decrease of reservoir particle size,the volume of pores connected by large throats and the volume of large pores show a decreasing trend,and the distribution and peak ranges of throat and pore radius shift to smaller size in an orderly manner.The upper limits of throat radius,porosity and permeability of unconventional reservoirs in Fengcheng Formation are approximately 0.7μm,8%and 0.1×10^(−3)μm^(2),respectively.(2)As the reservoir particle size decreases,the distribution and peak ranges of pores hosting retained oil and movable oil are shifted to a smaller size in an orderly manner.With the increase of driving pressure,the amount of retained and movable oil of the larger particle reservoir samples shows a more obvious trend of decreasing and increasing,respectively.(3)With the increase of throat radius,the driving pressure of reservoir with different particle levels presents three stages,namely rapid decrease,slow decrease and stabilization.The oil driving pressures of various reservoirs and the differences of them decrease with the increase of temperature and obviously decrease with the increase of throat radius.According to the above experimental analysis,it is concluded that the deep shale oil of Fengcheng Formation in Mahu Sag has great potential for production under geological conditions.展开更多
Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)region.In this study,we conduct a comparative analysis of the mesospher...Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)region.In this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December 2014.These two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,respectively.However,overall good agreement is observed between the two radars in terms of horizontal winds and tide observations.The results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal tides.Moreover,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal dynamics.The investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both radars.This finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor radars.Results of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.展开更多
This paper deals with the blow-up rate of positive solution for a semilinearparabolic system coupled in the equations and boundary condition. The upper and lower bounds ofblow-up rates are obtained.
Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nannin...Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nanning,Guangxi.This marks the first report of Diabolepis and Styloichthys beside Qujing,Yunnan,and the latest occurrence of Psarolepis to date.The fossil community displays significant similarities to the Xujiachong Assemblage,and provides new data for the Lower Devonian stratigraphic correlation between southwestern China and northern Vietnam.Given the latest dating constraint based on the conodont evidence,we regard that the Xujiachong Assemblage has a much longer range than previously supposed,extending from the latest Lochkovian to the end of Pragian.We propose that the transition of the Nahkaoling and Lianhuashan formations in Nanning might correspond to the Guijiatun Formation in Qujing.The relatively large size of fish individuals from Guangxi is probably attributed to the increase in the oxygen content of the ocean.展开更多
文摘BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in the pelvis,hips,and knees,the inverse relationship concerning knee pathology undergoing total knee arthroplasty(TKA)has been examined by a limited number of studies,yielding inconclusive results.AIM To generate evidence of the effect of TKA on the SSA from existing literature.METHODS Databases like PubMed,EMBASE,and Scopus were used to identify articles related to the“knee spine syndrome”phenomenon using a combination of subject terms and keywords such as“spinopelvic parameters”,“sagittal spinal balance”,and“total knee arthroplasty”were used with appropriate Boolean operators.Studies measuring the SSA following TKA were included,and research was conducted as per preferred reporting items for systematic review and metaanalysis guidelines.RESULTS A total of 475 participants had undergone TKA,and six studies measuring SSA were analysed.Following TKA,pelvic tilt was the only parameter that showed significant changes,while lumbar lordosis(LL),pelvic incidence,and sacral slope were non-significant,as evident from the forest plots.CONCLUSION The body's sagittal alignment is a complex balance between pelvic,spine,and lower extremity parameters.TKA,while having the potential to correct the flexion contracture,can also correct it.Still,the primary SSA for spinal pathology,i.e.,LL,may not be corrected in patients with co-existent spinal degenerative disease.
文摘BACKGROUND Demineralized bone matrix(DBM)is a commonly utilized allogenic bone graft substitute to promote osseous union.However,little is known regarding outcomes following DBM utilization in foot and ankle surgical procedures.AIM To evaluate the clinical and radiographic outcomes following DBM as a biological adjunct in foot and ankle surgical procedures.METHODS During May 2023,the PubMed,EMBASE and Cochrane library databases were systematically reviewed to identify clinical studies examining outcomes following DBM for the management of various foot and ankle pathologies.Data regarding study characteristics,patient demographics,subjective clinical outcomes,radiological outcomes,complications,and failure rates were extracted and analyzed.In addition,the level of evidence(LOE)and quality of evidence(QOE)for each individual study was also assessed.Thirteen studies were included in this review.RESULTS In total,363 patients(397 ankles and feet)received DBM as part of their surgical procedure at a weighted mean follow-up time of 20.8±9.2 months.The most common procedure performed was ankle arthrodesis in 94 patients(25.9%).Other procedures performed included hindfoot fusion,1st metatarsophalangeal joint arthrodesis,5th metatarsal intramedullary screw fixation,hallux valgus correction,osteochondral lesion of the talus repair and unicameral talar cyst resection.The osseous union rate in the ankle and hindfoot arthrodesis cohort,base of the 5th metatarsal cohort,and calcaneal fracture cohort was 85.6%,100%,and 100%,respectively.The weighted mean visual analog scale in the osteochondral lesions of the talus cohort improved from a pre-operative score of 7.6±0.1 to a post-operative score of 0.4±0.1.The overall complication rate was 27.2%,the most common of which was non-union(8.8%).There were 43 failures(10.8%)all of which warranted a further surgical procedure.CONCLUSION This current systematic review demonstrated that the utilization of DBM in foot and ankle surgical procedures led to satisfactory osseous union rates with favorable wound complication rates.Excellent outcomes were observed in patients undergoing fracture fixation augmented with DBM,with mixed evidence supporting the routine use of DBM in fusion procedures of the ankle and hindfoot.However,the low LOE together with the low QOE and significant heterogeneity between the included studies reinforces the need for randomized control trials to be conducted to identify the optimal role of DBM in the setting of foot and ankle surgical procedures.
文摘BACKGROUND Peripheral artery disease(PAD)affects millions globally,with a 5.6%prevalence in 2015 impacting 236 million adults,rising above 10%in those over 60 due to factors like diabetes and smoking.Post-revascularization,single antiplatelet therapy(SAPT)is standard,but dual antiplatelet therapy(DAPT)may improve outcomes,though duration and bleeding risks are unclear.The 2024 American College of Cardiology/American Heart Association guidelines endorse short-term DAPT,yet evidence gaps remain in comparative efficacy and safety.We hypothesized that DAPT reduces cardiovascular events and reinterventions vs SAPT without significantly elevating bleeding in PAD patients’post-lower extremity revascularization.AIM To evaluate the efficacy and safety of DAPT vs SAPT in PAD patients’post-revascularization.METHODS This systematic review and meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,searching PubMed,EMBASE,and ScienceDirect up to July 2025.Included were randomized controlled trials(RCTs)and cohort studies from various global settings(e.g.,hospitals,tertiary care)comparing DAPT(aspirin plus P2Y12 inhibitor for>1 month)to SAPT in symptomatic PAD patients undergoing endovascular or surgical revascularization(n up to 28244 participants selected via eligibility criteria).Data were pooled using random-effects models for risk ratio(RR)with 95%CI;heterogeneity was assessed via the I²statistic.Quality appraisal used Risk of Bias in Non-randomized Studies of Interventions for cohorts and Risk of Bias 2.0 for RCTs;certainty was evaluated via Grading of Recommendations Assessment,Development and Evaluation(GRADE).RESULTS Twelve studies(3 RCTs,9 cohorts,conducted 2010–2025 with follow-ups of 6 months to 5 years)were included.DAPT showed no significant difference but a trend toward reduced all-cause mortality(RR:0.52,95%CI:0.27–1.01,P=0.05,DAPT of 298/9545 events vs SAPT of 165/566 events)or stroke(RR:0.72,95%CI:0.30–1.72,P=0.46,DAPT of 16/3729 events vs SAPT of 41/7673 events)vs SAPT.DAPT significantly reduced cardiac mortality(RR:0.46,95%CI:0.27–0.80,P=0.006,DAPT of 78/2903 events vs SAPT of 171/1465 events,risk difference:-5.4%),myocardial infarction(RR:0.82,95%CI:0.71–0.94,P=0.004,DAPT of 233/7704 events vs SAPT of 262/9130 events,risk difference:-1.8%),and major reintervention(RR:0.58,95%CI:0.35–0.98,P=0.04,DAPT of 803/205 events vs SAPT of 1197/4 events,risk difference:-42%).Bleeding showed no difference(RR:1.12,95%CI:0.42–3.03,P=0.82,DAPT of 195/2775 events vs SAPT of 202/8234 events).Heterogeneity was high(I^(2)=59%–97%).Quality revealed moderate to serious bias in cohorts and some concerns in RCTs;GRADE certainty moderate for cardiac mortality,myocardial infarction,reintervention,low for others due to inconsistency and imprecision.CONCLUSION DAPT reduces cardiac mortality,myocardial infarction,and major reintervention risks compared to SAPT in PAD post-revascularization without apparent bleeding increase,though limited by heterogeneity and low certainty for some outcomes.
文摘Sixth Generation(6G)mobile communication networks will involve sensing as a new function,with the overwhelming trend of Integrated Sensing And Communications(ISAC).Although expanding the serving range of the networks,there exists performance trade-offbetween communication and sensing,in that they have competitions on the physical resources.Different resource allocation schemes will result in different sensing and communication performance,thus influencing the system’s overall performance.Therefore,how to model the system’s overall performance,and how to optimize it are key issues for ISAC.Relying on the large-scale deployment of the networks,cooperative ISAC has the advantages of wider coverage,more robust performance and good compatibility of multiple monostatic and multistatic sensing,compared to the non-cooperative ISAC.How to capture the performance gain of cooperation is a key issue for cooperative ISAC.To address the aforementioned vital problems,in this paper,we analyze the sensing accuracy gain,propose a unified ISAC performance evaluation framework and design several optimization methods in cooperative ISAC systems.The cooperative sensing accuracy gain is theoretically analyzed via Cramér Rao lower bound.The unified ISAC performance evaluation model is established by converting the communication mutual information to the effective minimum mean squared error.To optimize the unified ISAC performance,we design the optimization algorithms considering three factors:base stations’working modes,power allocation schemes and waveform design.Through simulations,we show the performance gain of the cooperative ISAC system and the effectiveness of the proposed optimization methods.
基金Supported by the Sichuan Province Regional Innovation Cooperation Project(21QYCX0048)Sinopec Science and Technology Department Project(P21048-3)。
文摘According to the complex differential accumulation history of deep marine oil and gas in superimposed basins,the Lower Paleozoic petroleum system in Tahe Oilfield of Tarim Basin is selected as a typical case,and the process of hydrocarbon generation and expulsion,migration and accumulation,adjustment and transformation of deep oil and gas is restored by means of reservoine-forming dynamics simulation.The thermal evolution history of the Lower Cambrian source rocks in Tahe Oilfield reflects the obvious differences in hydrocarbon generation and expulsion process and intensity in different tectonic zones,which is the main reason controlling the differences in deep oil and gas phases.The complex transport system composed of strike-slip fault and unconformity,etc.controlled early migration and accumulation and late adjustment of deep oil and gas,while the Middle Cambrian gypsum-salt rock in inner carbonate platform prevented vertical migration and accumulation of deep oil and gas,resulting in an obvious"fault-controlled"feature of deep oil and gas,in which the low potential area superimposed by the NE-strike-slip fault zone and deep oil and gas migration was conducive to accumulation,and it is mainly beaded along the strike-slip fault zone in the northeast direction.The dynamic simulation of reservoir formation reveals that the spatio-temporal configuration of"source-fault-fracture-gypsum-preservation"controls the differential accumulation of deep oil and gas in Tahe Oilfield.The Ordovician has experienced the accumulation history of multiple periods of charging,vertical migration and accumulation,and lateral adjustment and transformation,and deep oil and gas have always been in the dynamic equilibrium of migration,accumulation and escape.The statistics of residual oil and gas show that the deep stratum of Tahe Oilfield still has exploration and development potential in the Ordovician Yingshan Formation and Penglaiba Formation,and the Middle and Upper Cambrian ultra-deep stratum has a certain oil and gas resource prospect.This study provides a reference for the dynamic quantitative evaluation of deep oil and gas in the Tarim Basin,and also provides a reference for the study of reservoir formation and evolution in carbonate reservoir of paleo-craton basin.
基金Supported by the National Natural Science Foundation of China(No.62071482)Shaanxi Association of Science and Technology Youth Talent Support Program Project,China(No.20230137)+1 种基金the Innovative Talents Cultivate Program for Technology Innovation Team of ShaanXi Province,China(No.2024RS-CXTD-08)the Youth Talent Lifting Project of the China Association for Science and Technology(No.2021-JCJQ-QT-018).
文摘The resource allocation technique is of great significance in achieving frequency spectrum coexistence in Joint Radar-Communication(JRC) systems, by which the problem of radio frequency spectrum congestion can be well alleviated. A Robust Joint Frequency Spectrum and Power Allocation(RJFSPA) strategy is proposed for the Coexisting Radar and Communication(CRC)system. Specifically, we consider the uncertainty of target Radar Cross Section(RCS) and communication channel gain to formulate a bi-objective optimization model. The joint probabilities that the Cramér-Rao Lower Bound(CRLB) of each target satisfying the localization accuracy threshold and the Communication Data Ratio(CDR) of each user satisfying the communication threshold are simultaneously maximized, under the constraint of the total power budget. A Three-Stage Alternating Optimization Method(TSAOM) is proposed to obtain the Best-Known Pareto Subset(BKPS) of this problem, where the frequency spectrum, radar power, and communicator power are allocated using the greedy search and standard convex optimization methods, respectively. Simulation results confirm the effectiveness of the proposed RJFSPA strategy, compared with the resource allocation methods in a uniform manner and that ignores the uncertainties. The efficiency of the TSAOM is also verified by the comparison with the exhaustive search-based method.
基金Supported by NSFC(Nos.11971236,11901419)the Foundation in Higher Education Institutions of Henan Province(No.23A110020)。
文摘We introduce and study the relation between Pesin-Pitskel topological pressure on an arbitrary subset and measure theoretic pressure of Borel probability measure for nonautonomous dynamical systems,which is an extension of the classical definition of Bowen topological entropy.We show that the Pesin-Pitskel topological pressure can be determined by the local pressures of measures in nonautonomous case and establish a variational principle for Pesin-Pitskel topological pressure on compact subsets in the context of nonautonomous dynamical systems.
基金Basic Research Spe-cial Project of Suzhou Science and Technology Bureau(SSD2024050).
文摘Objective Venous thromboembolism is a highly prevalent condition after polytrauma,and recognized as an important factor contributing to poor prognosis.The aim of this study was to investigate the risk factors for lower extremity deep venous thrombosis(LEDVT)in a severely traumatized population and to evaluate their predictive value for LEDVT.Methods This was a retrospective,single-center observational study.All subjects were severely traumatized patients who were admitted to the Traumatic Intensive Care Unit from January 2021 to May 2024.Based on Doppler ultrasound findings of both lower extremities from the time of injury to 30 days post-injury,patients who developed LEDVT were enrolled in the LEDVT group,and those who did not develop LEDVT were enrolled in the NLEDVT group.Demographic,clinical,and laboratory data were collected upon admission.Multivariable logistic regression analysis was performed to identify risk factors for LEDVT.Receiver operating characteristic(ROC)curve was used to evaluate the overall fit of the final model.Results There were 56 patients enrolled in the LEDVT group and 81 patients in the NLEDVT group.Age,Aggregate Index of Systemic Inflammation(AISI),Systemic Inflammation Response Index(SIRI),ICU length of stay,and albumin were identified as independent risk factors for LEDVT(all P<0.05).The area under their ROC curves were 0.604,0.657,0.694,0.668,and 0.405,respectively.Combined model for early clinical prediction of LEDVT in severely traumatized patients by age,SIRI,AISI,and albumin resulted in an area under the ROC curve of 0.805(95%CI:0.73-0.88,SE=0.037).Conclusion The combination of age,SIRI,AISI,and albumin has a predictive value for LEDVT in severely traumatized patients.
基金supported financially by the National Natural Science Foundation of China(31100499 and 31672394)the Major Science and Technology Projects in Zhejiang Province(2020C02045)Zhejiang Science and Technology Commissioner Team Project.
文摘Tobacco polysaccharides were extracted by hot water extraction,and purified and separated using DEAE-52 cellulose chromatography columns,and three purified polysaccharide fractions,YCT-1,YCT-2,and YCT-3,were finally obtained.The physicochemical properties of the three fractions were analyzed by ultraviolet spectroscopy,high-performance liquid chromatography and high-performance gel chromatography.The in vitro antioxidant activity of tobacco polysaccharides was compared among different fractions by using DPPH radical,hydroxyl radical scavenging assay and potassium ferricyanide method.The in vitro hypoglycemic activity was compared usingα-amylase andα-glucosidase activity inhibition assay.And the in vitro hypolipidemic activity were investigated by using pancreatic lipase activity inhibition assay and HepG-2 intracellular lipid accumulation assay.All the results showed that the constituent monosaccharides of the three tobacco polysaccharide fractions were similar,but the molar percentages of each monosaccharide were different.The average molecular weights of the three components were 27,727 Da,27,587 Da,and 66,517 Da,respectively,and the scavenging activities on DPPH radicals and hydroxyl radicals were at a high level with good quantitative-effect relationships.The reducing power were much lower than that of the positive control VC,and the three polysaccharide fractions had a weak inhibitory ability onα-amylase activity,but showed excellent inhibitory ability onα-glucosidase and pancreatic lipase activity.In addition,the results of cellular experiments showed that all three fractions were able to inhibit lipid over-accumulation in HepG-2 cells by increasing the mRNA expression levels of PPAR-α,CPT-1A,and CYP7A1 genes,and the tobacco polysaccharide YCT-3 showed the best effect.The mechanism by which YCT-3 ameliorated the over-accumulation of intracellular lipids in HepG-2 cells was found to be related to its influence on the expression of miR-155-3p and miR-17-3p in the exosomes of HepG-2 cells.
基金supported in part by the Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.20230126).
文摘In this article, an unknown system dynamics estimator-based impedance control method is proposed for the lower limb exoskeleton to stimulate the tracking flexibility with the terminal target position when suffering parametric inaccuracies and unexpected disturbances. To reinforce the robust performance, via constructing the filtering operation-based dynamic relation, i.e., invariant manifold, the unknown system dynamics estimators are employed to maintain the accurate perturbation identification in both the hip and knee subsystem. Besides, a funnel control technique is designed to govern the convergence process within a minor overshoot and a higher steady-state precision. Meanwhile, an interactive complaint result can be obtained with the aid of the impedance control, where the prescribed terminal trajectory can be adjusted into the interaction variable-based target position by the force–position mapping, revealing the dynamic influence between the impedance coefficient (stiffness and damping) and the adjusted position magnitude. A sufficient stability analysis verifies the ultimately uniformly bounded results of all the error signals, and even the angle errors can be regulated within the predefined funnel boundary in the whole convergence. Finally, some simulations are provided to demonstrate the validity and superiority including the enhanced interaction flexibility and robustness.
基金Supported by The National Research Foundation of Korea Grant funded by the Korea Government,No.00219725.
文摘In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with lateral recess stenosis.The impact of spinal pain-related disability extends significantly,causing substantial human suffering and medical costs.Each county has its preferred treatment strategies for spinal pain.Here,we explore the lower back pain(LBP)treatment algorithm recommended in France.The treatment algorithm for LBP recommended by the French National Authority for Health emphasizes early patient activity and minimal medication use.It encourages the continuation of daily activities,limits excessive medication and spinal injections,and incorporates psychological assessments and non-pharmacological therapies for chronic cases.However,the algorithm may not aggressively address acute pain in the early stages,potentially delaying relief and increasing the risk of chronicity.Additionally,the recommended infiltrations primarily involve caudal epidural steroid injections,with limited consideration for other injection procedures,such as transforaminal or interlaminar epidural steroid injections.The fixed follow-up timeline may not accommodate patients who do not respond to initial treatment or experience intense pain,potentially delaying the exploration of alternative therapies.Despite these limitations,understanding the strengths and weaknesses of the French approach could inform adaptations in LBP treatment strategies globally,potentially enhancing patient outcomes and satisfaction across diverse healthcare systems.
基金Supported by the“Tianshan Talent”Project of Xinjiang(2022TSYCLJ0070)CNPC Technology Project(2023ZZ18)。
文摘Based on the latest results of near-source exploration in the Middle and Lower Jurassic of the Tuha Basin,a new understanding of the source rocks,reservoir conditions,and source-reservoir-cap rock combinations of the Jurassic Shuixigou Group in the Taibei Sag is established using the concept of the whole petroleum system,and the coal-measure whole petroleum system is analyzed thoroughly.The results are obtained in three aspects.First,the coal-measure source rocks of the Badaowan Formation and Xishanyao Formation and the argillaceous source rocks of the Sangonghe Formation in the Shuixigou Group exhibit the characteristics of long-term hydrocarbon generation,multiple hydrocarbon generation peaks,and simultaneous oil and gas generation,providing sufficient oil and gas sources for the whole petroleum system in the Jurassic coal-bearing basin.Second,multi-phase shallow braided river delta–shallow lacustrine deposits contribute multiple types of reservoirs,e.g.sandstone,tight sandstone,shale and coal rock,in slope and depression areas,providing effective storage space for the petroleum reservoir formation in coal-measure strata.Third,three phases of hydrocarbon charging and structural evolution,as well as effective configuration of multiple types of reservoirs,result in the sequential accumulation of conventional-unconventional hydrocarbons.From high structural positions to depression,there are conventional structural and structural-lithological reservoirs far from the source,low-saturation structural-lithological reservoirs near the source,and tight sandstone gas,coal rock gas and shale oil accumulations within the source.Typically,the tight sandstone gas and coal rock gas are the key options for further exploration,and the shale oil and gas in the depression area is worth of more attention.The new understanding of the whole petroleum system in the coal measures could further enrich and improve the geological theory of the whole petroleum system,and provide new ideas for the overall exploration of oil and gas resources in the Tuha Basin.
基金Aeronautical Science Foundation of China (2007ZC53030)
文摘As an important parameter in the single airborne passive locating system, the rate of phase difference change contains range information of the radio emitter. Taking single carrier sine pulse signals as an example, this article illustrates the principle of passive location through measurement of rates of phase difference change and analyzes the structure of measurement errors. On the basis of the Cramér-Rao lower bound (CRLB), an algorithm associated with time-chips is proposed to determine the rates of pha...
文摘Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models.
基金supported by the National High Level Hospital Clinical Research Funding(No.BJ-2023-066).
文摘Objective This study aims to analyze the burden of lower respiratory infections in Chinese elderly people aged 70 and above.Methods This study utilized Global Burden of Disease(GBD)1990-2050 prediction data to analyze changes in mortality rates and disability-adjusted life year(DALY)rates for lower respiratory infections in the elderly population(aged 70 and above)in China from 1990 to 2050.It also discusses future trends in the burden of lower respiratory infections(LRI)in China under different scenarios.Results According to GBD predictions,the burden of lower respiratory infections in the elderly aged 70 years and above in China is lower than the global average.The burden has been decreasing from 1990 to 2020,but is projected to increase from 2020 to 2050.Scenario-based predictions suggest that,under scenarios involving improvements in nutrition and vaccination,the burden of lower respiratory infections in the elderly in China is expected to be the lowest in 2050.Conclusion This study indicates that the burden of lower respiratory infections in elderly people aged 70 years and above in China remains a significant public health issue and may worsen.The government should consider strengthening the preventive measures and management strategies for respiratory infections in the elderly population.
文摘BACKGROUND Most patients who were included in previous studies on achalasia had increased lower esophageal sphincter(LES)pressure.Peroral endoscopic myotomy(POEM)has been confirmed to be effective at relieving the clinical symptoms of achalasia associated with increased LES pressure.AIM To identify the safety and efficacy of POEM for patients with normal LES integrated relaxation pressure(LES-IRP).METHODS The clinical data of patients who underwent POEM successfully in The First Medical Center of Chinese PLA General Hospital were retrospectively analyzed.A total of 481 patients who underwent preoperative high-resolution manometry(HRM)at our hospital were ultimately included in this research.According to the HRM results,the patients were divided into two groups:71 patients were included in the normal LES-IRP group(LES-IRP<15 mmHg)and 410 patients were included in the increased LES-IRP group(LES-IRP≥15 mmHg).Clinical characteristics,procedure-related parameters,adverse events,and outcomes were compared between the two groups to evaluate the safety and efficacy of POEM for patients with normal LES-IRP.RESULTS Among the 481 patients included in our study,209 were males and 272 were females,with a mean age of 44.2 years.All patients underwent POEM without severe adverse events.The median pre-treatment Eckardt scores of the normal LES-IRP and increased LES-IRP groups were 7.0 and 7.0(P=0.132),respectively,decreasing to 1.0 and 1.0 post-treatment(P=0.572).The clinical success rate of the normal LES-IRP group was 87.3%(62/71),and that of the increased LES-IRP group was 91.2%(374/410)(P=0.298).Reflux symptoms were measured by the GerdQ questionnaire,and the percentages of patients with GerdQ scores≥9 in the normal LES-IRP and increased LES-IRP groups were 8.5%and 10.7%,respectively(P=0.711).After matching,the rates of clinical success and the rates of GerdQ score≥9 were not significantly different between the two groups.CONCLUSION Our results suggest that POEM is safe and effective for achalasia and patients with normal LES-IRP.In addition,in patients with normal LES-IRP,compared with those with increased LES-IRP,POEM was not associated with a greater incidence of reflux symptoms.
基金Supported by Leading Talent Program of Autonomous Region(2022TSYCLJ0070)PetroChina Prospective and Basic Technological Project(2021DJ0108)Natural Science Foundation for Outstanding Young People in Shandong Province(ZR2022YQ30).
文摘Based on the experimental results of casting thin section,low temperature nitrogen adsorption,high pressure mercury injection,nuclear magnetic resonance T2 spectrum,contact angle and oil-water interfacial tension,the relationship between pore throat structure and crude oil mobility characteristics of full particle sequence reservoirs in the Lower Permian Fengcheng Formation of Mahu Sag,Junggar Basin,are revealed.(1)With the decrease of reservoir particle size,the volume of pores connected by large throats and the volume of large pores show a decreasing trend,and the distribution and peak ranges of throat and pore radius shift to smaller size in an orderly manner.The upper limits of throat radius,porosity and permeability of unconventional reservoirs in Fengcheng Formation are approximately 0.7μm,8%and 0.1×10^(−3)μm^(2),respectively.(2)As the reservoir particle size decreases,the distribution and peak ranges of pores hosting retained oil and movable oil are shifted to a smaller size in an orderly manner.With the increase of driving pressure,the amount of retained and movable oil of the larger particle reservoir samples shows a more obvious trend of decreasing and increasing,respectively.(3)With the increase of throat radius,the driving pressure of reservoir with different particle levels presents three stages,namely rapid decrease,slow decrease and stabilization.The oil driving pressures of various reservoirs and the differences of them decrease with the increase of temperature and obviously decrease with the increase of throat radius.According to the above experimental analysis,it is concluded that the deep shale oil of Fengcheng Formation in Mahu Sag has great potential for production under geological conditions.
基金supported by the National Natural Science Foundation of China (Grant Nos. 42125402 and 42174183)the National Key Technologies R&D Program of China (Grant No.2022YFF0503703)+2 种基金the B-type Strategic Priority Program of the Chinese Academy of Sciences (Grant No. XDB41000000)the foundation of the National Key Laboratory of Electromagnetic Environment and the Fundamental Research Funds for the Central Universitiesthe Chinese Meridian Project
文摘Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)region.In this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December 2014.These two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,respectively.However,overall good agreement is observed between the two radars in terms of horizontal winds and tide observations.The results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal tides.Moreover,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal dynamics.The investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both radars.This finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor radars.Results of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.
文摘This paper deals with the blow-up rate of positive solution for a semilinearparabolic system coupled in the equations and boundary condition. The upper and lower bounds ofblow-up rates are obtained.
文摘Here we report a left cheek plate of Psarolepis,a postparietal shield of Youngolepis,a skull of Diabolepis,and a scale of Styloichthys from the Lianhuashan and Nahkaoling formations(Lochkovian,Lower Devonian)of Nanning,Guangxi.This marks the first report of Diabolepis and Styloichthys beside Qujing,Yunnan,and the latest occurrence of Psarolepis to date.The fossil community displays significant similarities to the Xujiachong Assemblage,and provides new data for the Lower Devonian stratigraphic correlation between southwestern China and northern Vietnam.Given the latest dating constraint based on the conodont evidence,we regard that the Xujiachong Assemblage has a much longer range than previously supposed,extending from the latest Lochkovian to the end of Pragian.We propose that the transition of the Nahkaoling and Lianhuashan formations in Nanning might correspond to the Guijiatun Formation in Qujing.The relatively large size of fish individuals from Guangxi is probably attributed to the increase in the oxygen content of the ocean.
