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How delaying post-silking senescence in lower leaves of maize plants increases carbon and nitrogen accumulation and grain yield 被引量:3
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作者 Rongfa Li Dandan Hu +5 位作者 Hao Ren Qinglong Yang Shuting Dong Jiwang Zhang Bin Zhao Peng Liu 《The Crop Journal》 SCIE CSCD 2022年第3期853-863,共11页
Planting maize at high densities leads to early leaf senescence,and the resulting reduction in the number of lower leaves affects the plant’s root function and lowers its grain yield.However,the nature of the process... Planting maize at high densities leads to early leaf senescence,and the resulting reduction in the number of lower leaves affects the plant’s root function and lowers its grain yield.However,the nature of the process by which lower leaf senescence affects biomass accumulation and grain yield formation in maize is not clear.This study aimed to shed light on how these factors are related by investigating the effects of the plant growth regulator 6-benzyladenine(6-BA)on the senescence of lower leaves of maize plants.In two maize cultivars planted at densities of 67,500(low density,LD)and 90,000(high density,HD)plants ha^(-1),plants treated with 6-BA maintained a high green leaf area index(LAI)longer than control(CK)plants,enabling them to maintain a higher photosynthetic rate for a longer period of time and produce more biomass before reaching physiological maturity.Spraying the lower leaves of maize plants with a 6-BA solution increased the distribution of;C-photosynthates to their roots,lower leaves and bracts,a result that can be ascribed to a decreased retention of;C-photosynthates in the stem and grain.In both seasons of the experiment,maize plants treated with 6-BA accumulated more N in grain and maintained a higher N content in roots and leaves,especially in lower leaves,than CK.Increased C assimilation in the lower leaves may explain why N uptake in plants subjected to the 6-BA treatment exceeded that in CK plants and why both photosynthesis rate and dry matter accumulation were maintained throughout grain filling.Our results suggest that a suitable distribution of C and N in leaves post-silking may maintain plant root function,increase N use efficiency,maximize the duration of high LAI,and increase grain yield. 展开更多
关键词 13C-Photosynthate distribution Nitrogen uptake Maize grain yield delaying lower leaf senescence Post-silking
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PROGRESS AND PERSPECTIVE OF ACUPUNCTURE AND MOXIBUSTION IN DELAYING SENILITY
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作者 黄诚 陈汉平 《World Journal of Acupuncture-Moxibustion》 1995年第3期42-50,共9页
In this paper, we reviewed the developing history of delaying senility of acupunctureand moxibustion, summarized 41 reports about the effects of acupuncture and moxibustion on elderly,normal subject and the "defi... In this paper, we reviewed the developing history of delaying senility of acupunctureand moxibustion, summarized 41 reports about the effects of acupuncture and moxibustion on elderly,normal subject and the "deficiency syndrome" model animal, and expounded the rnechanisms in the aspects of immunology, endocrinology and biology. In addition, we also discussed the influence fac-tors and the developing trends of delaying senility of acupuncture and moxibustion in corning years. 展开更多
关键词 ACUPUNCTURE MOXIBUSTION delaying senility AGING
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Earthquake triggering and delaying caused by fault interaction on Xianshuihe fault belt, southwestern China
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作者 张秋文 张培震 +2 位作者 王乘 汪一鹏 Michael A Ellis 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第2期156-165,共10页
The coseismic Coulomb stress change caused by fault interaction and its influences on the triggering and delaying of earthquake are briefly discussed. The Xianshuihe fault belt consists of Luhuo, Daofu, Kangding, Qian... The coseismic Coulomb stress change caused by fault interaction and its influences on the triggering and delaying of earthquake are briefly discussed. The Xianshuihe fault belt consists of Luhuo, Daofu, Kangding, Qianning and Ganzi fault. Luohuo (MS=7.6, 1973)-Kangding (MS=6.2, 1975)-Daofu (MS=6.9, 1981)-Ganzi (MS=6.0, 1982) earthquake is a seismic sequence continuous on the time axis with magnitude greater than 6.0. They occurred on the Luhuo, Kangding, Daofu and Ganzi fault, respectively. The coseismic Coulomb stress changes caused by each earthquake on its surrounding major faults and microcracks are calculated, and their effects on the triggering and delaying of the next earthquake and aftershocks are analyzed. It is shown that each earthquake of the sequence occurred on the fault segment with coseismic Coulomb stress increases caused by its predecessors, and most after-shocks are distributed along the microcracks with relatively larger coseismic Coulomb stress increases resulted from the main shock. With the fault interaction considered, the seismic potential of each segment along Xianshuihe fault belt is reassessed, and contrasted with those predicted results ignoring coseismic Coulomb stress change, the significance of fault interaction and its effect on triggering and delaying of earthquake are emphasized. It is con-cluded that fault interaction plays a very important role on seismic potential of Xianshuihe fault belt, and the maximal change of future earthquake probability on fault segment is up to 30.5%. 展开更多
关键词 coseismic Coulomb stress change fault interaction earthquake triggering and delaying seismic potential assessment Xianshuihe fault belt
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CLINICAL OBSERVATION OF THE EFFECT OF HEALTH-PRESERVING MOXIBUSTION ON DELAYING AGING
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作者 王玲玲 吴中朝 +1 位作者 徐兰凤 邱茂良 《World Journal of Acupuncture-Moxibustion》 1996年第3期25-30,共6页
The present paper reports a clinical observation of the effect of health-preservingmoxibustion in the aged people without apparent organic diseases. Results show that the health-preserving moxibustion has an evident a... The present paper reports a clinical observation of the effect of health-preservingmoxibustion in the aged people without apparent organic diseases. Results show that the health-preserving moxibustion has an evident action in lessening aging symptoms and improving physio-logic functions of the senile body. It is held in traditional Chinese medicine that from the middle-aged period on, the decline of kidney Qi is an important cause of senility and deficiency of thespleen and blood stasis also play a role in some degree. Health-preserving moxibustion ofShenque and Zusanli has actions in warming Yang, reinforcing Qi and promoting blood circulationto remove obstruction in meridians. It is thus a method for self health protection. 展开更多
关键词 Senility/delaying AGING MOXIBUSTION THERAPY
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Experimental Method Of Cosmetics Human Efficacy Evaluation-Delaying Skin Aging Efficacy
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作者 Wang Peng Zhang Hongyan +3 位作者 Sha Ou Guo Ruoxi Zhang Han Zhang Lei 《China Detergent & Cosmetics》 2021年第4期66-69,共4页
This paper briefly introduce the test method for human evaluation of cosmetics to delay skin aging,and provide reference for the test of relevant indexes.By formulating a reasonable test plan and choosing appropriate ... This paper briefly introduce the test method for human evaluation of cosmetics to delay skin aging,and provide reference for the test of relevant indexes.By formulating a reasonable test plan and choosing appropriate equipment to test the improvement of the skin aging characteristics before and after the product is used,it can provide a scientific basis for claiming the effect of delaying skin aging. 展开更多
关键词 delaying skin aging efficacy evaluation COSMETICS
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Attosecond ionization time delays in strong-field physics
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作者 马永哲 倪宏程 吴健 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期102-121,共20页
Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laserbased pump-probe interrogation techniques have made possible the temporal resolution of ultrafast ele... Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laserbased pump-probe interrogation techniques have made possible the temporal resolution of ultrafast electronic processes on the attosecond timescale, including photoionization and tunneling ionization. These interrogation techniques include the attosecond streak camera, the reconstruction of attosecond beating by interference of two-photon transitions, and the attoclock. While the former two are usually employed to study photoionization processes, the latter is typically used to investigate tunneling ionization. In this review, we briefly overview these timing techniques towards an attosecond temporal resolution of ionization processes in atoms and molecules under intense laser fields. In particular, we review the backpropagation method, which is a novel hybrid quantum-classical approach towards the full characterization of tunneling ionization dynamics. Continued advances in the interrogation techniques promise to pave the pathway towards the exploration of ever faster dynamical processes on an ever shorter timescale. 展开更多
关键词 strong-field ionization ATTOSECOND time delay photoionization time delay tunneling time delay attosecond streak camera reconstruction of attosecond beating by interference of two-photon transitions(RABBITT) attoclock backpropagation
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Analysis and Design of Time-Delay Impulsive Systems Subject to Actuator Saturation
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作者 Chenhong Zhu Xiuping Han Xiaodi Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期196-204,共9页
This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is s... This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is shown that the system can be stabilized by a class of saturated delayed-impulses regardless of the length of input delays. Conversely, when the system is originally stable, it is shown that under some conditions, the system is robust with respect to sufficient small delayed-impulses. Moreover, the design problem of the controller with the goal of obtaining a maximized estimate of the domain of attraction is formulated via a convex optimization problem. Three examples are provided to demonstrate the validity of the main results. 展开更多
关键词 Delayed impulses impulsive control impulsive disturbance nonlinear systems SATURATION
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Designing Proportional-Integral Consensus Protocols for Second-Order Multi-Agent Systems Using Delayed and Memorized State Information
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作者 Honghai Wang Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期878-892,共15页
This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consens... This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state information.Under the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay system.Note that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the system.In this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first derived.Then allowable regions of consensus protocol parameters are estimated.Some necessary and sufficient conditions for determining effective protocol parameters are provided.The designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent system.Moreover,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are investigated.Furthermore,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems. 展开更多
关键词 Consensus protocol Hurwitz stability multi-agent systems quasi-polynomials time delay
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User Preference Aware Hierarchical Edge-User Cooperative Caching Strategy
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作者 Wu Dapeng Yang Lin +2 位作者 Cui Yaping He Peng Wang Ruyan 《China Communications》 SCIE CSCD 2024年第6期69-86,共18页
The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been conside... The emergence of various new services has posed a huge challenge to the existing network architecture.To improve the network delay and backhaul pressure,caching popular contents at the edge of network has been considered as a feasible scheme.However,how to efficiently utilize the limited caching resources to cache diverse contents has been confirmed as a tough problem in the past decade.In this paper,considering the time-varying user requests and the heterogeneous content sizes,a user preference aware hierarchical cooperative caching strategy in edge-user caching architecture is proposed.We divide the caching strategy into three phases,that is,the content placement,the content delivery and the content update.In the content placement phase,a cooperative content placement algorithm for local content popularity is designed to cache contents proactively.In the content delivery phase,a cooperative delivery algorithm is proposed to deliver the cached contents.In the content update phase,a content update algorithm is proposed according to the popularity of the contents.Finally,the proposed caching strategy is validated using the MovieLens dataset,and the results reveal that the proposed strategy improves the delay performance by at least 35.3%compared with the other three benchmark strategies. 展开更多
关键词 cooperative caching network delay timevarying popularity user preference
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THE ASYMPTOTIC BEHAVIOR AND OSCILLATION FOR A CLASS OF THIRD-ORDER NONLINEAR DELAY DYNAMIC EQUATIONS
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作者 黄先勇 邓勋环 王其如 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期925-946,共22页
In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existe... In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existence of eventually positive solutions having upper bounds and tending to zero.Third,we obtain new oscillation criteria by employing the Potzsche chain rule.Then,using the generalized Riccati transformation technique and averaging method,we establish the Philos-type oscillation criteria.Surprisingly,the integral value of the Philos-type oscillation criteria,which guarantees that all unbounded solutions oscillate,is greater than θ_(4)(t_(1),T).The results of Theorem 3.5 and Remark 3.6 are novel.Finally,we offer four examples to illustrate our results. 展开更多
关键词 nonlinear delay dynamic equations NONOSCILLATION asymptotic behavior Philostype oscillation criteria generalized Riccati transformation
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Relaxed Stability Criteria for Time-Delay Systems:A Novel Quadratic Function Convex Approximation Approach
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作者 Shenquan Wang Wenchengyu Ji +2 位作者 Yulian Jiang Yanzheng Zhu Jian Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期996-1006,共11页
This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By i... This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying delays.By introducing two adjustable parameters and two free variables,a novel convex function greater than or equal to the quadratic function is constructed,regardless of the sign of the coefficient in the quadratic term.The developed lemma can also be degenerated into the existing quadratic function negative-determination(QFND)lemma and relaxed QFND lemma respectively,by setting two adjustable parameters and two free variables as some particular values.Moreover,for a linear system with time-varying delays,a relaxed stability criterion is established via our developed lemma,together with the quivalent reciprocal combination technique and the Bessel-Legendre inequality.As a result,the conservatism can be reduced via the proposed approach in the context of constructing Lyapunov-Krasovskii functionals for the stability analysis of linear time-varying delay systems.Finally,the superiority of our results is illustrated through three numerical examples. 展开更多
关键词 Equivalent reciprocal combination technique quadratic function convex approximation approach STABILITY timevarying delay
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A NOTE ON THE GENERAL STABILIZATION OF DISCRETE FEEDBACK CONTROL FOR NON-AUTONOMOUS HYBRID NEUTRAL STOCHASTIC SYSTEMS WITH A DELAY
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作者 冯立超 张春艳 +1 位作者 曹进德 武志辉 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1145-1164,共20页
Discrete feedback control was designed to stabilize an unstable hybrid neutral stochastic differential delay system(HNSDDS) under a highly nonlinear constraint in the H_∞ and exponential forms.Nevertheless,the existi... Discrete feedback control was designed to stabilize an unstable hybrid neutral stochastic differential delay system(HNSDDS) under a highly nonlinear constraint in the H_∞ and exponential forms.Nevertheless,the existing work just adapted to autonomous cases,and the obtained results were mainly on exponential stabilization.In comparison with autonomous cases,non-autonomous systems are of great interest and represent an important challenge.Accordingly,discrete feedback control has here been adjusted with a time factor to stabilize an unstable non-autonomous HNSDDS,in which new Lyapunov-Krasovskii functionals and some novel technologies are adopted.It should be noted,in particular,that the stabilization can be achieved not only in the routine H_∞ and exponential forms,but also the polynomial form and even a general form. 展开更多
关键词 hybrid neutral stochastic differential delay system discrete feedback control general stabilization polynomial stabilization
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Examining the association between delay discounting,delay aversion and physical activity in Chinese adults with type-2 diabetes mellitus
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作者 Yong-Dong An Guo-Xia Ma +3 位作者 Xing-Kui Cai Ying Yang Fang Wang Zhan-Lin Zhang 《World Journal of Diabetes》 SCIE 2024年第4期675-685,共11页
BACKGROUND The role of physical activity in diabetes is critical,influencing this disease's development,man-agement,and overall outcomes.In China,22.3%of adults do not meet the minimum level of physical activity r... BACKGROUND The role of physical activity in diabetes is critical,influencing this disease's development,man-agement,and overall outcomes.In China,22.3%of adults do not meet the minimum level of physical activity recommended by the World Health Organization.Therefore,it is imperative to identify the factors that contributing to lack of physical activity must be identified.AIM To investigate the relationship among delay discounting,delay aversion,glycated hemoglobin(HbA1c),and various levels of physical activity in Chinese adults diagnosed with type 2 diabetes mellitus(T2DM).METHODS In 2023,400 adults with T2DM were recruited from the People's Hospital of Linxia Hui Autonomous Prefecture of Gansu Province.A face-to-face questionnaire was used to gather demographic data and details on physical activity,delay discounting,and delay aversion.In addition,HbA1c levels were measured in all 400 participants.The primary independent variables considered were delay discounting and delay aversion.The outcome variables included HbA1c levels and different intensity levels of physical activity,including walking,moderate physical activity,and vigorous physical activity.Multiple linear regression models were utilized to assess the relationship between delay discounting,delay aversion,and HbA1c levels,along with the intensity of different physical activity measured in met-hours per week.RESULTS After controlling for the sample characteristics,delay discounting was negatively associated with moderate physical activity(β=-2.386,95%CI:-4.370 to-0.401).Meanwhile,delay aversion was negatively associated with the level of moderate physical activity(β=-3.527,95%CI:-5.578 to-1.476)in the multiple linear regression model,with statistically significant differences.CONCLUSION Elevated delay discounting and increased delay aversion correlated with reduced levels of moderate physical activity.Result suggests that delay discounting and aversion may influence engagement in moderate physical activity.This study recommends that health administration and government consider delay discounting and delay aversion when formulating behavioral intervention strategies and treatment guidelines involving physical activity for patients with T2DM,which may increase participation in physical activity.This study contributes a novel perspective to the research on physical activity in adults with T2DM by examining the significance of future health considerations and the role of emotional responses to delays. 展开更多
关键词 Type 2 diabetes mellitus Delay discounting Delay aversion Physical activity
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Development and validation of a nomogram model for predicting the risk of pre-hospital delay in patients with acute myocardial infarction
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作者 Jiao-Yu Cao Li-Xiang Zhang Xiao-Juan Zhou 《World Journal of Cardiology》 2024年第2期80-91,共12页
BACKGROUND Acute myocardial infarction(AMI)is a severe cardiovascular disease caused by the blockage of coronary arteries that leads to ischemic necrosis of the myocardium.Timely medical contact is critical for succes... BACKGROUND Acute myocardial infarction(AMI)is a severe cardiovascular disease caused by the blockage of coronary arteries that leads to ischemic necrosis of the myocardium.Timely medical contact is critical for successful AMI treatment,and delays increase the risk of death for patients.Pre-hospital delay time(PDT)is a significant challenge for reducing treatment times,as identifying high-risk patients with AMI remains difficult.This study aims to construct a risk prediction model to identify high-risk patients and develop targeted strategies for effective and prompt care,ultimately reducing PDT and improving treatment outcomes.AIM To construct a nomogram model for forecasting pre-hospital delay(PHD)likelihood in patients with AMI and to assess the precision of the nomogram model in predicting PHD risk.METHODS A retrospective cohort design was employed to investigate predictive factors for PHD in patients with AMI diagnosed between January 2022 and September 2022.The study included 252 patients,with 180 randomly assigned to the development group and the remaining 72 to the validation group in a 7:3 ratio.Independent risk factors influencing PHD were identified in the development group,leading to the establishment of a nomogram model for predicting PHD in patients with AMI.The model's predictive performance was evaluated using the receiver operating characteristic curve in both the development and validation groups.RESULTS Independent risk factors for PHD in patients with AMI included living alone,hyperlipidemia,age,diabetes mellitus,and digestive system diseases(P<0.05).A characteristic curve analysis indicated area under the receiver operating characteristic curve values of 0.787(95%confidence interval:0.716–0.858)and 0.770(95%confidence interval:0.660-0.879)in the development and validation groups,respectively,demonstrating the model's good discriminatory ability.The Hosmer–Lemeshow goodness-of-fit test revealed no statistically significant disparity between the anticipated and observed incidence of PHD in both development and validation cohorts(P>0.05),indicating satisfactory model calibration.CONCLUSION The nomogram model,developed with independent risk factors,accurately forecasts PHD likelihood in AMI individuals,enabling efficient identification of PHD risk in these patients. 展开更多
关键词 Pre-hospital delay Acute myocardial infarction Risk prediction NOMOGRAM
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A predictive model for regional zenith tropospheric delay correction
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作者 Yu Lei Danning Zhao 《Astronomical Techniques and Instruments》 CSCD 2024年第1期76-83,共8页
The conventional zenith tropospheric delay(ZTD)model(known as the Saastamoinen model)does not consider seasonal variations affecting the delay,giving it low accuracy and stability.This may be improved with adjustments... The conventional zenith tropospheric delay(ZTD)model(known as the Saastamoinen model)does not consider seasonal variations affecting the delay,giving it low accuracy and stability.This may be improved with adjustments to account for annual and semi-annual variations.This method uses ZTD data provided by the Global Geodetic Observing System to analyze seasonal variations in the bias of the Saastamoinen model in Asia,and then constructs a model with seasonal variation corrections,denoted as SSA.To overcome the dependence of the model on in-situ meteorological parameters,the SSA+GPT3 model is formed by combining the SSA and GPT3(global pressure-temperature)models.The results show that the introduction of annual and semi-annual variations can substantially improve the Saastamoinen model,yielding small and time-stable variations in bias and root mean square(RMS).In summer and autumn,the bias and RMS are noticeably smaller than those from the Saastamoinen model.In addition,the SSA model performs better in low-latitude and low-altitude areas,and bias and RMS decease with the increase of latitude or altitude.The prediction accuracy of the SSA model is also evaluated for external consistency.The results show that the accuracy of the SSA model(bias:-0.38 cm,RMS:4.43 cm)is better than that of the Saastamoinen model(bias:1.45 cm,RMS:5.16 cm).The proposed method has strong applicability and can therefore be used for predictive ZTD correction across Asia. 展开更多
关键词 Zenith tropospheric delay Saastamoinen model Seasonal variations Asian area Accuracy analysis
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Delayed neurological dysfunction following posterior laminectomy with lateral mass screw fixation:A case report and review of literature
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作者 Rui-Zhong Yan Chao Chen +6 位作者 Chu-Ran Lin Yan-Hui Wei Zhi-Jian Guo Ya-Kun Li Quan Zhang He-Yi Shen Hao-Lin Sun 《World Journal of Clinical Cases》 SCIE 2024年第7期1356-1364,共9页
BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity an... BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity and mortality.Delayed neurological dysfunction is diagnosed in cases when symptoms present>3 d postoperatively.Owing to its rarity,the risk factors for delayed neurological dysfunction are unclear.Consequently,this condition can result in irreversible neurological deficits and serious consequences.In this paper,we present a case of postoperative SEH that developed three days after hematoma evacuation.CASE SUMMARY A 68-year-old man with an American Spinal Injury Association(ASIA)grade C injury was admitted to our hospital with neck pain and tetraplegia following a fall.The C3-C7 posterior laminectomy and the lateral mass screw fixation surgery were performed on the tenth day.Postoperatively,the patient showed no changes in muscle strength or ASIA grade.The patient experienced neck pain and subcutaneous swelling on the third day postoperatively,his muscle strength decreased,and his ASIA score was grade A.Magnetic resonance imaging showed hypointense signals on T1 weighted image(T1WI)and T2WI located behind the epidural space,with spinal cord compression.Emergency surgical intervention for the hematoma was performed 12 h after onset.Although hypoproteinemia and pleural effusion did not improve in the perioperative period,the patient recovered to ASIA grade C on day 30 after surgery,and was transferred to a functional rehabilitation exercise unit.CONCLUSION This case shows that amelioration of low blood albumin and pleural effusion is an important aspect of the perioperative management of cervical surgery.Surgery to relieve the pressure on the spinal cord should be performed as soon as possible to decrease neurological disabilities. 展开更多
关键词 Delayed postoperative spinal epidural hematoma Complications Spinal surgery HYPOPROTEINEMIA Risk factor Case report
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Current knowledge for the risk factors of early permanent pacemaker implantation following transcatheter aortic valve replacement and what is next for the primary prevention?
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作者 Gen-Min Lin Wei-Chun Huang Chih-Lu Han 《World Journal of Cardiology》 2024年第2期54-57,共4页
In this editorial,we comprehensively summarized the preoperative risk factors of early permanent pacemaker implantation after transcatheter aortic valve replacement(TAVR)among patients with severe aortic stenosis from... In this editorial,we comprehensively summarized the preoperative risk factors of early permanent pacemaker implantation after transcatheter aortic valve replacement(TAVR)among patients with severe aortic stenosis from several renowned clinical studies and focused on the primary prevention of managing the modifiable factors,e.g.,paroxysmal atrial fibrillation before the TAVR. 展开更多
关键词 Permanent pacemaker implantation Transcatheter aortic valve replacement Interventricular conduction delay DIABETES Supraventricular arrhythmia
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Surgical treatment of an old avulsion fracture of the ischial tuberosity and ischial ramus: A case report
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作者 Zi-Ru Chen Shi-Jie Liao Fu-Chun Yang 《World Journal of Orthopedics》 2024年第1期94-100,共7页
BACKGROUND Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities.According to previous literature,the mo... BACKGROUND Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities.According to previous literature,the most commonly involved sports are soccer,sprinting,and gymnastics,in descending order.Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare.CASE SUMMARY A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip.She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior.Eventually,she underwent surgery and obtained satisfactory treatment results.CONCLUSION Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery.For old fractures with nonunion and chronic buttock pain,surgery is a preferred therapeutic choice with good treatment outcomes. 展开更多
关键词 Ischial tuberosity Ischial ramus Avulsion fracture Delayed diagnosis Splitleap injury Case report
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Adaptive predictor-based control for a helicopter system with input delays:Design and experiments
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作者 Siri Marte Schlanbusch Jing Zhou 《Journal of Automation and Intelligence》 2024年第1期50-56,共7页
In this paper,we consider a 2-degrees-of-freedom(DOF)helicopter system subject to long input delays and uncertain system parameters.To address the challenges including unknown system parameters and input delays in con... In this paper,we consider a 2-degrees-of-freedom(DOF)helicopter system subject to long input delays and uncertain system parameters.To address the challenges including unknown system parameters and input delays in control design,we develop an adaptive predictor-feedback control law to achieve trajectory tracking.Stability of the closed-loop system is further established,where the tracking errors are shown to converge towards zero.Through simulation and experiments on the helicopter system,we illustrate that tracking of a desired trajectory is achieved with the proposed control scheme. 展开更多
关键词 Adaptive control BACKSTEPPING Helicopter system Time delays
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Exact controllability of rational expectations model with multiplicative noise and input delay
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作者 Wenjing Wang Juanjuan Xu +1 位作者 Huanshui Zhang Minyue Fu 《Journal of Automation and Intelligence》 2024年第1期19-25,共7页
This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a suffi... This paper considers the rational expectations model with multiplicative noise and input delay,where the system dynamics rely on the conditional expectations of future states.The main contribution is to obtain a sufficient condition for the exact controllability of the rational expectations model.In particular,we derive a sufficient Gramian matrix condition and a rank condition for the delay-free case.The key is the solvability of the backward stochastic difference equations with input delay which is derived from the forward and backward stochastic system. 展开更多
关键词 Rational expectations model Exact controllability Exactly null controllability Multiplicative noise Input delay
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