BACKGROUND Fracture nonunion represents a challenging complication during fracture repair,often necessitating surgical intervention.Teriparatide,a recombinant human parathyroid hormone,has demonstrated promise in enha...BACKGROUND Fracture nonunion represents a challenging complication during fracture repair,often necessitating surgical intervention.Teriparatide,a recombinant human parathyroid hormone,has demonstrated promise in enhancing fracture healing,although its efficacy in treating established nonunion remains under investigation.CASE SUMMARY We report a case of a 27-year-old male who presented with a right humerus fracture following a traffic accident.Despite undergoing open reduction and internal fixation,the fracture resulted in a delayed union and subsequent nonunion.After 4 years of conservative management,teriparatide treatment was initiated due to persistent nonunion.Teriparatide injections were administered daily for 6 months,resulting in complete fracture healing and resolution of pain.CONCLUSION Our case demonstrates the successful use of teriparatide in treating a prolonged nonunion of a humerus fracture.Teriparatide may provide a valuable therapeutic option for established bone nonunion,even in cases that have not responded to conservative treatments.展开更多
The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly fo...The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly focuses on the following three key aspects.First,the classical ensemble method is adopted to conduct a comprehensive and in-depth analysis of two-dimensional(2D)matter–wave pulses in Bose–Fermi mixed gases(including linear and nonlinear pulses).Second,under the strict constraints of unitary systems,a coupled Kd V equation is successfully derived,and the prolongation structure theory is skillfully used to carry out detailed calculations and analyses on this equation.Thus,the prolongation algebra of this equation is accurately determined,and the corresponding Lax pair is rigorously derived.Finally,based on the carefully obtained Lax pair from the prolongation structure theory,the soliton solutions of this equation are further analyzed in depth,and intuitive images of each soliton solution are carefully drawn.This lays a solid foundation for subsequent detailed research on these soliton characteristics and provides great convenience.展开更多
BACKGROUND:This study aimed to develop and validate a nomogram to estimate the probability of prolonged intensive care unit(ICU)stays.METHODS:Pediatric patients who underwent cardiac surgery were included,with data co...BACKGROUND:This study aimed to develop and validate a nomogram to estimate the probability of prolonged intensive care unit(ICU)stays.METHODS:Pediatric patients who underwent cardiac surgery were included,with data collected from the pediatric intensive care database.The datasets were randomly divided into a training set(75%)and a testing set(25%).A nomogram model was developed to predict prolonged ICU stays in the training set and then validated in the testing set.RESULTS:A total of 795 patients and 266 patients were assigned to the training and testing sets,respectively,with consistent variables.The nomogram developed from the training set included eight characteristics:age,systolic blood pressure,respiratory rate,bicarbonate,direct bilirubin,high-sensitivity C-reactive protein,international normalized ratio,and operation time.The area under the curve values of the nomogram in the training and testing sets were 0.812 and 0.736,respectively.The nomogram demonstrated excellent discrimination and calibration.Decision curve analysis showed that the use of the nomogram resulted in more favorable outcomes compared with the strategies of treating all or none of the patients.CONCLUSION:This study presents a nomogram that may enable early identification of high-risk patients and facilitates tailored postoperative care and better outcomes after pediatric cardiac surgery.展开更多
Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment opt...Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment options include pharmacological and electrical cardioversion,each carrying specific risks.AF may resolve spontaneously,but often recurs,making a“watch-andwait”strategy a reasonable approach to avoid unnecessary antiarrhythmic therapy.展开更多
Poyang Lake,China's largest freshwater lake,is a critical wintering ground for most of the global Siberian Grane(Grus leucogeranus)population.However,increasingly prolonged dry seasons have degraded the natural we...Poyang Lake,China's largest freshwater lake,is a critical wintering ground for most of the global Siberian Grane(Grus leucogeranus)population.However,increasingly prolonged dry seasons have degraded the natural wetlands of Poyang Lake,forcing Siberian Cranes to shift to artificial habitats.From 2015 to 2023,field surveys revealed a substantial increase in the number of Siberian Cranes in artificial habitats,with peak counts reaching 3000individuals,accounting for up to 53%of the species'global population.Satellite telemetry of 13 individuals further confirmed the spatial use of these habitats,highlighting their consistent reliance on artificial sites over multiple years.Seven high-use hotspots were identified outside of Poyang Lake,including two artificial provisioning sites that supported dense foraging flocks for extended periods.Satellite telemetry confirmed this trend,with artificial habitats making up to 64.2%of the occurrence sites in some years.This reliance on artificial habitats was closely linked to the reduced tuber biomass in natural wetlands and low winter water levels in Poyang Lake,which collectively explained 83%of the variance in crane abundance in artificial habitats.Artificial habitat use peaked in December and January,indicating marked seasonal variation.Siberian Cranes also exhibited a pronounced circadian rhythm,foraging in artificial habitats during the day and returning to natural wetlands to roost at night.Despite the shift toward artificial habitats,natural wetlands remain critical for nighttime refuge.The continued dependence on artificial habitats raises concerns about disease transmission owing to dense congregations.Conservation strategies should prioritize both the careful management of artificial provisioning sites and the restoration of natural wetlands to improve food and habitat availability within natural ecosystems,ultimately enabling the return of Siberian Cranes to their traditional natural habitats.展开更多
Prolonged grief disorder(PGD)is characterized by intense and persistent grief that significantly impairs daily functioning.For bereaved parents,the loss of a child represents an unparalleled emotional challenge,placin...Prolonged grief disorder(PGD)is characterized by intense and persistent grief that significantly impairs daily functioning.For bereaved parents,the loss of a child represents an unparalleled emotional challenge,placing them at heightened risk of developing PGD.This review traces the evolution of PGD from early con-ceptualization to current definitions in the International Classification of Diseases,11th revision,and Diagnostic and Statistical Manual of Mental Disorders,5th Edition,Text Revision.Building on this historical foundation,the analysis examined the prevalence,risk factors,and diagnostic criteria of PGD in bereaved parents,with particular attention to sex differences,the nature of the loss,and the time elapsed since the child’s death.Furthermore,this review examines the multidimensional consequences of PGD on parents,including its emotional,physiological,and functional effects.Evidence-based treatments for PGD,such as psychotherapeutic approaches and emerging interventions,are also discussed.By synthesizing existing research,this review provides a comprehensive under-standing of PGD among bereaved parents,highlights the unique challenges they face,and offers practical insights and recommendations for clinicians working with this population.展开更多
To evaluate the efficacy and safety of gemcitabine （GEM） at 30 min standard-dose infusion （30 min-SDI） compared with prolonged low-dose infusion （P-LDI） in patients with advanced non-small-cell lung cancer （NS...To evaluate the efficacy and safety of gemcitabine （GEM） at 30 min standard-dose infusion （30 min-SDI） compared with prolonged low-dose infusion （P-LDI） in patients with advanced non-small-cell lung cancer （NSCLC）. Electronic databases including Pubmed, EMbase, Cochrane Library, CNKI, CBM, and VIP were searched using keywords ＂GEM＂, ＂P-LDI＂, and ＂NSCLC＂. Review Manager 5.3 was used to perform the recta-analysis. Primary endpoints were overall response rate （ORR） and 1-year survival rate （1-year SR）. Secondary endpoints were grade 3/4 hematotoxicity and nausea/vomiting. Six randomized controlled trials （RCTs） with a total of 637 patients were included. The results showed that P-LDI was superior in ORR （OR = 1.50, 95% CI： 1.08-2.10, P = 0.02）, but had an equal 1-year SR （OR = 1.27, 95 % CI： 0.90-1.79, P = 0.18） as compared with 30 min-SDl. For grade 3/4 adverse events, there was no significant difference in anemia （OR = 1.84, 95% CI： 0.61-5.57, P = 0.28） and nausea/vomiting （OR = 1.15, 95% CI： 0.63-2.12, P = 0.64） between the two treatments. However, patients with P-LDI experienced less leukopenia （OR = 0.64, 95% CI： 0.43-0.97, P = 0.04） and thrombocytopenia （OR = 0.37, 95% CI： 0.17-0.80, P = 0.01）. P-LDI was superior in terms of ORR, experienced less grade 3/4 thrombocytopenia and leukopenia compared with 30 min-SDI, and could be a viable treatment option for advanced NSCLC.展开更多
This study examined regional prolonged low temperature （PLT） events in China from the observational station data for the period 1960–2008 using the new criteria. The new definition of a site PLT event is that the d...This study examined regional prolonged low temperature （PLT） events in China from the observational station data for the period 1960–2008 using the new criteria. The new definition of a site PLT event is that the daily minimum temperature does not exceed the 10th percentile threshold of the local daily minimum temperature climatology for at least 5 days at a station. The regional PLT event is defined as at least five adjacent stations exhibiting site PLT simultaneously for 5 d. Under the new definition, 552 regional PLT events were identified, and three indices： duration, extent, and intensity, as well as a comprehensive index （CI） were used to quantify the event severity. In addition, geographical patterns and temporal variations of regional PLT events were investigated using three event categories： strong, moderate, and weak. Spatially, strong events were mainly located in the north of Xinjiang and along the Yangtze River to the south of the Yangtze River; moderate events occurred in Xinjiang and south of the Yangtze River; and weak events occurred south of the Yellow River. The variation for the annual frequency of regional PLT events in China in the last 49 years showed a significant decreasing trend with a rate of-1.99 times per decade, and the significant transition decade was the 1980s.展开更多
Objective:To discuss the effect of prolonged second stage of labor on maternal and neonatal outcomes.Methods:A total of 101 primiparas with the length of second stage of labor longer than 2 h were selected and pregnan...Objective:To discuss the effect of prolonged second stage of labor on maternal and neonatal outcomes.Methods:A total of 101 primiparas with the length of second stage of labor longer than 2 h were selected and pregnant women with the length less than 2 h served as control.The maternal and neonatal outcomes of two groups were observed and compared.Results:A total of 62.1%(18/11) with the length of second stage of labor between 120 min and 180 min,46.7%(28/32) between 181 min and 240 min and 12 longer than 241 min underwent vaginal delivery.The longer the length of second stage of labor,the lower score of Apgar scale for infants in 1 min,and the higher the incidence of asphyxia.But there was no difference in scale in 5 min.As second stage of labor prolonged,the incidences of cesarean section and of postpartum hemorrhage increased. Conclusions:Almost half of puerperas with the length of second stage of labor longer than 2 h underwent vaginal delivery.The prolonged second stage of labor can decrease the score of Apgar scale in 1 min,increase the incidence of asphyxia,but has no effect on scale in 5 min.It still need more evidence from evidence medicine to definition of time and treatment of second stage of labor.展开更多
BACKGROUND Prolonged postoperative ileus(PPOI)is one of the common complications in gastric cancer patients who underwent gastrectomy.Evidence on the predictors of PPOI after gastrectomy is limited and few prediction ...BACKGROUND Prolonged postoperative ileus(PPOI)is one of the common complications in gastric cancer patients who underwent gastrectomy.Evidence on the predictors of PPOI after gastrectomy is limited and few prediction models of nomogram are used to estimate the risk of PPOI.We hypothesized that a predictive nomogram can be used for clinical risk estimation of PPOI in gastric cancer patients.AIM To investigate the risk factors for PPOI and establish a nomogram for clinical risk estimation.METHODS Between June 2016 and March 2017,the data of 162 patients with gastrectomy were obtained from a prospective and observational registry database.Clinical data of patients who fulfilled the criteria were obtained.Univariate and multivariable logistic regression models were performed to detect the relationship between variables and PPOI.A nomogram for PPOI was developed and verified by bootstrap resampling.The calibration curve was employed to detect the concentricity between the model probability curve and ideal curve.The clinical usefulness of our model was evaluated using the net benefit curve.RESULTS This study analyzed 14 potential variables of PPOI in 162 gastric cancer patients who underwent gastrectomy.The incidence of PPOI was 19.75%in patients with gastrectomy.Age older than 60 years,open surgery,advanced stage(III–IV),and postoperative use of opioid analgesic were independent risk factors for PPOI.We developed a simple and easy-to-use prediction nomogram of PPOI after gastrectomy.This nomogram had an excellent diagnostic performance[area under the curve(AUC)=0.836,sensitivity=84.4%,and specificity=75.4%].This nomogram was further validated by bootstrapping for 500 repetitions.The AUC of the bootstrap model was 0.832(95%CI:0.741–0.924).This model showed a good fitting and calibration and positive net benefits in decision curve analysis.CONCLUSION We have developed a prediction nomogram of PPOI for gastric cancer.This novel nomogram might serve as an essential early warning sign of PPOI in gastric cancer patients.展开更多
We examined the possible multiple defects induced by acute and prolonged exposure to high levels of manganese（Mn） solution by monitoring the endpoints of lifespan,development,reproduction,and stress response.Our dat...We examined the possible multiple defects induced by acute and prolonged exposure to high levels of manganese（Mn） solution by monitoring the endpoints of lifespan,development,reproduction,and stress response.Our data suggest that acute exposure（6 h） to Mn did not cause severe defects of life span,development,and reproduction,similarly,no significant defect could be found in animals exposed to a low concentration of Mn（2.5 μmol/L） for 48 h.In contrast,prolonged exposure（48 h） to high Mn concentrations（75 and 200 μmol/L） resulted in significant defects of life span,development,and reproduction,as well as the increase of the percentage of population with hsp-16.2：：gfp expression indicating the obvious induction of stress responses in exposed animals.Moreover,prolonged exposure（48 h） to high concentrations（75 and 200 μmol/L） of Mn decreased the expression levels of antioxidant genes of sod-1,sod-2,sod-3,and sod-4 compared to control.Therefore,prolonged exposure to high concentrations of Mn will induce the severe defects of life span,development,and reproduction in nematodes possibly by affecting the stress response and expression of antioxidant genes in Caenorhabditis elegans.展开更多
BACKGROUND Prolonged postoperative ileus(PPOI) is a prolonged state of "pathological"gastrointestinal(GI) tract dysmotility. There are relatively few studies examining the influence of preoperative nutrition...BACKGROUND Prolonged postoperative ileus(PPOI) is a prolonged state of "pathological"gastrointestinal(GI) tract dysmotility. There are relatively few studies examining the influence of preoperative nutritional status on the development of PPOI in patients who underwent GI surgery. The association between preoperative albumin and PPOI has not been fully studied. We hypothesized that preoperative albumin may be an independent indicator of PPOI.AIM To analyze the role of preoperative albumin in predicting PPOI and to establish a nomogram for clinical risk evaluation.METHODS Patients were drawn from a prospective hospital registry database of GI surgery.A total of 311 patients diagnosed with gastric or colorectal cancer between June 2016 and March 2017 were included. Potential predictors of PPOI were analyzed by univariate and multivariable logistic regression analyses, and a nomogram for quantifying the presence of PPOI was developed and internally validated.RESULTS The overall PPOI rate was 21.54%. Advanced tumor stage and postoperative opioid analgesic administration were associated with PPOI. Preoperative albumin was an independent predictor of PPOI, and an optimal cutoff value of 39.15 was statistically calculated. After adjusting multiple variables, per unit or per SD increase in albumin resulted in a significant decrease in the incidence of PPOI of 8%(OR = 0.92, 95%CI: 0.85-1.00, P = 0.046) or 27%(OR = 0.73, 95%CI:0.54-0.99, P = 0.046), respectively. Patients with a high level of preoperative albumin(≥ 39.15) tended to experience PPOI compared to those with low levels(< 39.15)(OR = 0.43, 95%CI: 0.24-0.78, P = 0.006). A nomogram for predicting PPOI was developed [area under the curve(AUC) = 0.741] and internally validated by bootstrap resampling(AUC = 0.725, 95%CI: 0.663-0.799).CONCLUSION Preoperative albumin is an independent predictive factor of PPOI in patients who underwent GI surgery. The nomogram provided a model to screen for early indications in the clinical setting.展开更多
AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected ...AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected for heart rate for each patient,with a prolonged QT cutoff defined as QT>450 ms for males and QT>470 ms for females.Multiple clinical variables were evaluated including sex,age,serum sodium,international normalized ratio,creatinine,total bilirubin,beta-blocker use,Model for EndStage Liver Disease(MELD),MELD-Na,and etiology of liver disease.RESULTS Among 406 ESLD patients analyzed,207(51.0%)had QT prolongation.The only clinical variable associated with QT prolongation was male gender(OR=3.04,95%CI:2.01-4.60,P<0.001).During the study period,187patients(46.1%)died.QT prolongation was a significant independent predictor of mortality(OR=1.69,95%CI:1.03-2.77,P=0.039).In addition,mortality was also associated with viral etiology of ESLD,elevated MELD score and its components(P<0.05 for all).No significant reversibility in the QT interval was seen after liver transplantation.CONCLUSION QT prolongation was commonly encountered in an ESLD population,especially in males,and served as a strong independent marker for increased mortality in ESLD patients.展开更多
AIM: To explore the impact of prolonged fraction dosedelivery time modeling intensity-modulated radiation therapy (IMRT) on cell killing of human hepatocellular carcinoma (HCC) HepG2 and Hep3B cell lines.METHODS: The ...AIM: To explore the impact of prolonged fraction dosedelivery time modeling intensity-modulated radiation therapy (IMRT) on cell killing of human hepatocellular carcinoma (HCC) HepG2 and Hep3B cell lines.METHODS: The radiobiological characteristics of human HCC HepG2 and Hep3b cell lines were studied with standard clonogenic assays, using standard linear-quadratic model and incomplete repair model to fit the dose-survival curves. The identical methods were also employed to investigate the biological effectiveness of irradiation protocols modeling clinical conventional fractionated external beam radiotherapy (EBRT, fraction delivery time 3 min) and IMRT with different prolonged fraction delivery time (15, 30, and 45 min). The differences of cell surviving fraction irradiated with different fraction delivery time were tested with paired t-test. Factors determining the impact of prolonged fraction delivery time on cell killing were analyzed.RESULTS: The α/β and repair half-time (T1/2) of HepG2and Hep3b were 3.1 and 7.4 Gy, and 22 and 19 min respectively. The surviving fraction of HepG2 irradiated modeling IMRT with different fraction delivery time was significantly higher than irradiated modeling EBRT and the cell survival increased more pronouncedly with the fraction delivery time prolonged from 15 to 45 min,while no significant differences of cell survival in Hep3b were found between different fraction delivery time protocols.CONCLUSION: The prolonged fraction delivery time modeling IMRT significantly decreased the cell killing in HepG2 but not in Hep3b. The capability of sub-lethal damage repair was the predominant factor determining the cell killing decrease. These effects, if confirmed by clinical studies, should be considered in designing IMRT treatments for HCC.展开更多
Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSding...Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.展开更多
Ischemic priapism is a rare occurrence which can cause severe erectile dysfunction(ED)without timely treatment.This retrospective study reports our experience in treating prolonged ischemic priapism and proposes our f...Ischemic priapism is a rare occurrence which can cause severe erectile dysfunction(ED)without timely treatment.This retrospective study reports our experience in treating prolonged ischemic priapism and proposes our further considerations.In this paper,a total of nine patients with prolonged ischemic priapism underwent one to three types of surgical shunts,including nine Winter shunts,two AI-Ghorab shunts and one Grayhack shunt.During the follow-up visit(after a mean of 21.11 months),all patients'postoperative characters were recorded,except one patient lost for death.Six postoperative patients accepted a 25-mg oral administration of sildenafil citrate.The erectile function of the patients was evaluated by their postoperative 5-item version of International Index of Erectile Function Questionnaire(IIEF-5),which were later compared with their premorbid scores.All patients had complete resolutions,and none relapsed.The resolution rate was 100%.Seven patients were resolved with Winter shunts,one with an AI-Ghorab shunt and one with a Grayhack shunt.The mean hospital stay was 8.22 days.There was only one urethral fistula,and the incidence of postoperative ED was 66.67%.Four patients with more than a 72-h duration of priapism had no response to the long-term phosphodiesterase type 5(PDE-5)inhibitor treatment.These results suggest that surgical shunts are an efficient approach to make the penis flaccid after prolonged priapism.However,the severe ED caused by prolonged duration is irreversible,and long-term PDE-5 inhibitor treatments are ineffective.Thus,we recommend early penile prosthesis surgeries for these patients.展开更多
The microstructural evolution and consequent changes in strength and ductility of advanced NANOBAIN steel during prolonged isothermal heat-treatment stages were investigated. The microstructure and mechanical properti...The microstructural evolution and consequent changes in strength and ductility of advanced NANOBAIN steel during prolonged isothermal heat-treatment stages were investigated. The microstructure and mechanical properties of nanostructured bainite were not expected to be influenced by extending the heat-treatment time beyond the optimum value because of the autotempering phenomenon and high tempering resistance. However, experimental results indicated that the microstructure was thermodynamically unstable and that prolonged austempering resulted in carbon depletion from high-carbon retained austenite and carbide precipitations. Therefore, austenite became thermally less stable and partially transformed into martensite during cooling to room temperature. Prolonged austempering did not lead to the typical tempering sequence of bainite, and the sizes of the microstructural constituents were independent of the extended heat-treatment times. This independence, in turn, resulted in almost constant ultimate tensile strength values. However, microstructural variations enhanced the yield strength and the hardness of the material at extended isothermal heat-treatment stages. Finally, although microstructural changes decreased the total elongation and impact toughness, considerable combinations of mechanical properties could still be achieved.展开更多
Purpose:This study aimed to evaluate the effectiveness of physical activity(PA)interrupting prolonged sitting(PS)on postprandial glycemia and insulin responses among adults.Methods:PubMed,EMBASE,Cochrane Library,Web o...Purpose:This study aimed to evaluate the effectiveness of physical activity(PA)interrupting prolonged sitting(PS)on postprandial glycemia and insulin responses among adults.Methods:PubMed,EMBASE,Cochrane Library,Web of Science,CINAHL,PsycINFO,and the China National Knowledge Infrastructure databases were searched through September 30,2020.Randomized controlled trials(RCTs)that examined the effect of all forms of PA interrupting PS on postprandial glycemia and/or insulin responses among adults without chronic diseases were included in this study.The risk of bias of included studies was evaluated based on the Cochrane tool.A network meta-analysis was performed to estimate the summary standardized mean differences(SMDs)with 95%confidence intervals(95%CIs)with random effects.Results:Thirty crossover RCTs were included in our review.These RCTs included 9 types of interventions that interrupted PS.When compared to PS by itself,light-intensity PA intermittent interrupting(LPA-INT)PS and moderate-intensity PA intermittent interrupting(MPA-INT)PS significantly lowered postprandial glycemia(SMD=-0.46,95%CI:-0.70 to-0.21;SMD=-0.69,95%CI:-1.00 to-0.37,respectively)and significantly reduced postprandial insulin response(SMD=-0.46,95%CI:-0.66 to-0.26;SMD=-0.47,95%CI:-0.77 to-0.17,respectively).Results of the clustered ranking plot indicated that MPA-INT was the most effective intervention in lowering postprandial glycemia and insulin responses.Conclusion:Replacing PS with MPA-INT or LPA-INT has a positive effect in reducing postprandial glycemia and insulin responses,with MPA-INT being the optimal intervention strategy.展开更多
An exceptionally prolonged heavy snow event(PHSE)occurred in southern China from 10 January to 3 February 2008,which caused considerable economic losses and many casualties.To what extent any dynamical model can predi...An exceptionally prolonged heavy snow event(PHSE)occurred in southern China from 10 January to 3 February 2008,which caused considerable economic losses and many casualties.To what extent any dynamical model can predict such an extreme event is crucial for disaster prevention and mitigation.Here,we found the three S2S models(ECMWF,CMA1.0 and CMA2.0)can predict the distribution and intensity of precipitation and surface air temperature(SAT)associated with the PHSE at 10-day lead and 10−15-day lead,respectively.The success is attributed to the models’capability in forecasting the evolution of two important low-frequency systems in the tropics and mid-latitudes[the persistent Siberian High and the suppressed phase of the Madden−Julian Oscillation(MJO)],especially in the ECMWF model.However,beyond the 15-day lead,the three models show almost no skill in forecasting this PHSE.The bias in capturing the two critical circulation systems is responsible for the low skill in forecasting the 2008 PHSE beyond the 15-day lead.On one hand,the models cannot reproduce the persistence of the Siberian High,which results in the underestimation of negative SAT anomalies over southern China.On the other hand,the models cannot accurately capture the suppressed convection of the MJO,leading to weak anomalous southerly and moisture transport,and therefore the underestimation of precipitation over southern China.The Singular Value Decomposition(SVD)analyses between the critical circulation systems and SAT/precipitation over southern China shows a robust historical relation,indicating the fidelity of the predictability sources for both regular events and extreme events(e.g.,the 2008 PHSE).展开更多
基金Supported by National Natural Science Foundation of China,No.82172441Suzhou City Major Disease Multicenter Clinical Research Project,No.DZXYJ202312+2 种基金Special Funding for Jiangsu Province Science and Technology Plan(Key Research and Development Program for Social Development),No.BE2023737Gusu Health Talent Plan Scientific Research Project,No.GSWS2022109Postgraduate Research and Practice Innovation Program of Jiangsu Province,No.SJCX24_2446.
文摘BACKGROUND Fracture nonunion represents a challenging complication during fracture repair,often necessitating surgical intervention.Teriparatide,a recombinant human parathyroid hormone,has demonstrated promise in enhancing fracture healing,although its efficacy in treating established nonunion remains under investigation.CASE SUMMARY We report a case of a 27-year-old male who presented with a right humerus fracture following a traffic accident.Despite undergoing open reduction and internal fixation,the fracture resulted in a delayed union and subsequent nonunion.After 4 years of conservative management,teriparatide treatment was initiated due to persistent nonunion.Teriparatide injections were administered daily for 6 months,resulting in complete fracture healing and resolution of pain.CONCLUSION Our case demonstrates the successful use of teriparatide in treating a prolonged nonunion of a humerus fracture.Teriparatide may provide a valuable therapeutic option for established bone nonunion,even in cases that have not responded to conservative treatments.
基金Project supported by the National Natural Science Foundation of China(Grant No.12261072)。
文摘The widespread popularization and application of laser technology have provided a powerful tool for a deeper understanding of the material world and given birth to several emerging research fields.This study mainly focuses on the following three key aspects.First,the classical ensemble method is adopted to conduct a comprehensive and in-depth analysis of two-dimensional(2D)matter–wave pulses in Bose–Fermi mixed gases(including linear and nonlinear pulses).Second,under the strict constraints of unitary systems,a coupled Kd V equation is successfully derived,and the prolongation structure theory is skillfully used to carry out detailed calculations and analyses on this equation.Thus,the prolongation algebra of this equation is accurately determined,and the corresponding Lax pair is rigorously derived.Finally,based on the carefully obtained Lax pair from the prolongation structure theory,the soliton solutions of this equation are further analyzed in depth,and intuitive images of each soliton solution are carefully drawn.This lays a solid foundation for subsequent detailed research on these soliton characteristics and provides great convenience.
基金supported by the National Natural Science Foundation of China(82230074,81971809 and 82372159)the Liangshan Prefecture Science and Technology Plan Project(23ZDYF0180 and 24YYYJ0043).
文摘BACKGROUND:This study aimed to develop and validate a nomogram to estimate the probability of prolonged intensive care unit(ICU)stays.METHODS:Pediatric patients who underwent cardiac surgery were included,with data collected from the pediatric intensive care database.The datasets were randomly divided into a training set(75%)and a testing set(25%).A nomogram model was developed to predict prolonged ICU stays in the training set and then validated in the testing set.RESULTS:A total of 795 patients and 266 patients were assigned to the training and testing sets,respectively,with consistent variables.The nomogram developed from the training set included eight characteristics:age,systolic blood pressure,respiratory rate,bicarbonate,direct bilirubin,high-sensitivity C-reactive protein,international normalized ratio,and operation time.The area under the curve values of the nomogram in the training and testing sets were 0.812 and 0.736,respectively.The nomogram demonstrated excellent discrimination and calibration.Decision curve analysis showed that the use of the nomogram resulted in more favorable outcomes compared with the strategies of treating all or none of the patients.CONCLUSION:This study presents a nomogram that may enable early identification of high-risk patients and facilitates tailored postoperative care and better outcomes after pediatric cardiac surgery.
文摘Atrial fibrillation(AF)is the most common arrhythmia in clinical setting and has been increasingly prevalent due to the aging population.AF is associated with a three to fivefold increased risk of stroke.Treatment options include pharmacological and electrical cardioversion,each carrying specific risks.AF may resolve spontaneously,but often recurs,making a“watch-andwait”strategy a reasonable approach to avoid unnecessary antiarrhythmic therapy.
基金supported by the National Natural Science Foundation of China(No.32260275)Fundamental Research Funds of CAF(CAFYBB2024ZA033)。
文摘Poyang Lake,China's largest freshwater lake,is a critical wintering ground for most of the global Siberian Grane(Grus leucogeranus)population.However,increasingly prolonged dry seasons have degraded the natural wetlands of Poyang Lake,forcing Siberian Cranes to shift to artificial habitats.From 2015 to 2023,field surveys revealed a substantial increase in the number of Siberian Cranes in artificial habitats,with peak counts reaching 3000individuals,accounting for up to 53%of the species'global population.Satellite telemetry of 13 individuals further confirmed the spatial use of these habitats,highlighting their consistent reliance on artificial sites over multiple years.Seven high-use hotspots were identified outside of Poyang Lake,including two artificial provisioning sites that supported dense foraging flocks for extended periods.Satellite telemetry confirmed this trend,with artificial habitats making up to 64.2%of the occurrence sites in some years.This reliance on artificial habitats was closely linked to the reduced tuber biomass in natural wetlands and low winter water levels in Poyang Lake,which collectively explained 83%of the variance in crane abundance in artificial habitats.Artificial habitat use peaked in December and January,indicating marked seasonal variation.Siberian Cranes also exhibited a pronounced circadian rhythm,foraging in artificial habitats during the day and returning to natural wetlands to roost at night.Despite the shift toward artificial habitats,natural wetlands remain critical for nighttime refuge.The continued dependence on artificial habitats raises concerns about disease transmission owing to dense congregations.Conservation strategies should prioritize both the careful management of artificial provisioning sites and the restoration of natural wetlands to improve food and habitat availability within natural ecosystems,ultimately enabling the return of Siberian Cranes to their traditional natural habitats.
文摘Prolonged grief disorder(PGD)is characterized by intense and persistent grief that significantly impairs daily functioning.For bereaved parents,the loss of a child represents an unparalleled emotional challenge,placing them at heightened risk of developing PGD.This review traces the evolution of PGD from early con-ceptualization to current definitions in the International Classification of Diseases,11th revision,and Diagnostic and Statistical Manual of Mental Disorders,5th Edition,Text Revision.Building on this historical foundation,the analysis examined the prevalence,risk factors,and diagnostic criteria of PGD in bereaved parents,with particular attention to sex differences,the nature of the loss,and the time elapsed since the child’s death.Furthermore,this review examines the multidimensional consequences of PGD on parents,including its emotional,physiological,and functional effects.Evidence-based treatments for PGD,such as psychotherapeutic approaches and emerging interventions,are also discussed.By synthesizing existing research,this review provides a comprehensive under-standing of PGD among bereaved parents,highlights the unique challenges they face,and offers practical insights and recommendations for clinicians working with this population.
文摘To evaluate the efficacy and safety of gemcitabine （GEM） at 30 min standard-dose infusion （30 min-SDI） compared with prolonged low-dose infusion （P-LDI） in patients with advanced non-small-cell lung cancer （NSCLC）. Electronic databases including Pubmed, EMbase, Cochrane Library, CNKI, CBM, and VIP were searched using keywords ＂GEM＂, ＂P-LDI＂, and ＂NSCLC＂. Review Manager 5.3 was used to perform the recta-analysis. Primary endpoints were overall response rate （ORR） and 1-year survival rate （1-year SR）. Secondary endpoints were grade 3/4 hematotoxicity and nausea/vomiting. Six randomized controlled trials （RCTs） with a total of 637 patients were included. The results showed that P-LDI was superior in ORR （OR = 1.50, 95% CI： 1.08-2.10, P = 0.02）, but had an equal 1-year SR （OR = 1.27, 95 % CI： 0.90-1.79, P = 0.18） as compared with 30 min-SDl. For grade 3/4 adverse events, there was no significant difference in anemia （OR = 1.84, 95% CI： 0.61-5.57, P = 0.28） and nausea/vomiting （OR = 1.15, 95% CI： 0.63-2.12, P = 0.64） between the two treatments. However, patients with P-LDI experienced less leukopenia （OR = 0.64, 95% CI： 0.43-0.97, P = 0.04） and thrombocytopenia （OR = 0.37, 95% CI： 0.17-0.80, P = 0.01）. P-LDI was superior in terms of ORR, experienced less grade 3/4 thrombocytopenia and leukopenia compared with 30 min-SDI, and could be a viable treatment option for advanced NSCLC.
基金supported jointly by the National Natural Science Foundation of China (GrantNo. 40975039)the Key Technologies R&D Program(Grant No. 2009BAC51B00)
文摘This study examined regional prolonged low temperature （PLT） events in China from the observational station data for the period 1960–2008 using the new criteria. The new definition of a site PLT event is that the daily minimum temperature does not exceed the 10th percentile threshold of the local daily minimum temperature climatology for at least 5 days at a station. The regional PLT event is defined as at least five adjacent stations exhibiting site PLT simultaneously for 5 d. Under the new definition, 552 regional PLT events were identified, and three indices： duration, extent, and intensity, as well as a comprehensive index （CI） were used to quantify the event severity. In addition, geographical patterns and temporal variations of regional PLT events were investigated using three event categories： strong, moderate, and weak. Spatially, strong events were mainly located in the north of Xinjiang and along the Yangtze River to the south of the Yangtze River; moderate events occurred in Xinjiang and south of the Yangtze River; and weak events occurred south of the Yellow River. The variation for the annual frequency of regional PLT events in China in the last 49 years showed a significant decreasing trend with a rate of-1.99 times per decade, and the significant transition decade was the 1980s.
文摘Objective:To discuss the effect of prolonged second stage of labor on maternal and neonatal outcomes.Methods:A total of 101 primiparas with the length of second stage of labor longer than 2 h were selected and pregnant women with the length less than 2 h served as control.The maternal and neonatal outcomes of two groups were observed and compared.Results:A total of 62.1%(18/11) with the length of second stage of labor between 120 min and 180 min,46.7%(28/32) between 181 min and 240 min and 12 longer than 241 min underwent vaginal delivery.The longer the length of second stage of labor,the lower score of Apgar scale for infants in 1 min,and the higher the incidence of asphyxia.But there was no difference in scale in 5 min.As second stage of labor prolonged,the incidences of cesarean section and of postpartum hemorrhage increased. Conclusions:Almost half of puerperas with the length of second stage of labor longer than 2 h underwent vaginal delivery.The prolonged second stage of labor can decrease the score of Apgar scale in 1 min,increase the incidence of asphyxia,but has no effect on scale in 5 min.It still need more evidence from evidence medicine to definition of time and treatment of second stage of labor.
基金Supported by the National Nature Science Foundation of China,No.81672319,No.81602507,and No.81773135the National Key Research and Development Plan,No.2017YFC0908300Beijing Nova Program,No.Z181100006218011
文摘BACKGROUND Prolonged postoperative ileus(PPOI)is one of the common complications in gastric cancer patients who underwent gastrectomy.Evidence on the predictors of PPOI after gastrectomy is limited and few prediction models of nomogram are used to estimate the risk of PPOI.We hypothesized that a predictive nomogram can be used for clinical risk estimation of PPOI in gastric cancer patients.AIM To investigate the risk factors for PPOI and establish a nomogram for clinical risk estimation.METHODS Between June 2016 and March 2017,the data of 162 patients with gastrectomy were obtained from a prospective and observational registry database.Clinical data of patients who fulfilled the criteria were obtained.Univariate and multivariable logistic regression models were performed to detect the relationship between variables and PPOI.A nomogram for PPOI was developed and verified by bootstrap resampling.The calibration curve was employed to detect the concentricity between the model probability curve and ideal curve.The clinical usefulness of our model was evaluated using the net benefit curve.RESULTS This study analyzed 14 potential variables of PPOI in 162 gastric cancer patients who underwent gastrectomy.The incidence of PPOI was 19.75%in patients with gastrectomy.Age older than 60 years,open surgery,advanced stage(III–IV),and postoperative use of opioid analgesic were independent risk factors for PPOI.We developed a simple and easy-to-use prediction nomogram of PPOI after gastrectomy.This nomogram had an excellent diagnostic performance[area under the curve(AUC)=0.836,sensitivity=84.4%,and specificity=75.4%].This nomogram was further validated by bootstrapping for 500 repetitions.The AUC of the bootstrap model was 0.832(95%CI:0.741–0.924).This model showed a good fitting and calibration and positive net benefits in decision curve analysis.CONCLUSION We have developed a prediction nomogram of PPOI for gastric cancer.This novel nomogram might serve as an essential early warning sign of PPOI in gastric cancer patients.
基金supported by the National Natural Science Foundation of China (No. 30771113, 30870810)the Program for New Century Excellent Talents in University
文摘We examined the possible multiple defects induced by acute and prolonged exposure to high levels of manganese（Mn） solution by monitoring the endpoints of lifespan,development,reproduction,and stress response.Our data suggest that acute exposure（6 h） to Mn did not cause severe defects of life span,development,and reproduction,similarly,no significant defect could be found in animals exposed to a low concentration of Mn（2.5 μmol/L） for 48 h.In contrast,prolonged exposure（48 h） to high Mn concentrations（75 and 200 μmol/L） resulted in significant defects of life span,development,and reproduction,as well as the increase of the percentage of population with hsp-16.2：：gfp expression indicating the obvious induction of stress responses in exposed animals.Moreover,prolonged exposure（48 h） to high concentrations（75 and 200 μmol/L） of Mn decreased the expression levels of antioxidant genes of sod-1,sod-2,sod-3,and sod-4 compared to control.Therefore,prolonged exposure to high concentrations of Mn will induce the severe defects of life span,development,and reproduction in nematodes possibly by affecting the stress response and expression of antioxidant genes in Caenorhabditis elegans.
基金the National Nature Science Foundation of China,No.81672319 and No.81972790Beijing Nova Program,No.Z181100006218011。
文摘BACKGROUND Prolonged postoperative ileus(PPOI) is a prolonged state of "pathological"gastrointestinal(GI) tract dysmotility. There are relatively few studies examining the influence of preoperative nutritional status on the development of PPOI in patients who underwent GI surgery. The association between preoperative albumin and PPOI has not been fully studied. We hypothesized that preoperative albumin may be an independent indicator of PPOI.AIM To analyze the role of preoperative albumin in predicting PPOI and to establish a nomogram for clinical risk evaluation.METHODS Patients were drawn from a prospective hospital registry database of GI surgery.A total of 311 patients diagnosed with gastric or colorectal cancer between June 2016 and March 2017 were included. Potential predictors of PPOI were analyzed by univariate and multivariable logistic regression analyses, and a nomogram for quantifying the presence of PPOI was developed and internally validated.RESULTS The overall PPOI rate was 21.54%. Advanced tumor stage and postoperative opioid analgesic administration were associated with PPOI. Preoperative albumin was an independent predictor of PPOI, and an optimal cutoff value of 39.15 was statistically calculated. After adjusting multiple variables, per unit or per SD increase in albumin resulted in a significant decrease in the incidence of PPOI of 8%(OR = 0.92, 95%CI: 0.85-1.00, P = 0.046) or 27%(OR = 0.73, 95%CI:0.54-0.99, P = 0.046), respectively. Patients with a high level of preoperative albumin(≥ 39.15) tended to experience PPOI compared to those with low levels(< 39.15)(OR = 0.43, 95%CI: 0.24-0.78, P = 0.006). A nomogram for predicting PPOI was developed [area under the curve(AUC) = 0.741] and internally validated by bootstrap resampling(AUC = 0.725, 95%CI: 0.663-0.799).CONCLUSION Preoperative albumin is an independent predictive factor of PPOI in patients who underwent GI surgery. The nomogram provided a model to screen for early indications in the clinical setting.
文摘AIM To determine the prevalence of QT prolongation in a large series of end stage liver disease(ESLD)patients and its association to clinical variables and mortality.METHODS The QT interval was measured and corrected for heart rate for each patient,with a prolonged QT cutoff defined as QT>450 ms for males and QT>470 ms for females.Multiple clinical variables were evaluated including sex,age,serum sodium,international normalized ratio,creatinine,total bilirubin,beta-blocker use,Model for EndStage Liver Disease(MELD),MELD-Na,and etiology of liver disease.RESULTS Among 406 ESLD patients analyzed,207(51.0%)had QT prolongation.The only clinical variable associated with QT prolongation was male gender(OR=3.04,95%CI:2.01-4.60,P<0.001).During the study period,187patients(46.1%)died.QT prolongation was a significant independent predictor of mortality(OR=1.69,95%CI:1.03-2.77,P=0.039).In addition,mortality was also associated with viral etiology of ESLD,elevated MELD score and its components(P<0.05 for all).No significant reversibility in the QT interval was seen after liver transplantation.CONCLUSION QT prolongation was commonly encountered in an ESLD population,especially in males,and served as a strong independent marker for increased mortality in ESLD patients.
基金Supported by the Natural Science Foundation of Guangdong Province, No. 013056
文摘AIM: To explore the impact of prolonged fraction dosedelivery time modeling intensity-modulated radiation therapy (IMRT) on cell killing of human hepatocellular carcinoma (HCC) HepG2 and Hep3B cell lines.METHODS: The radiobiological characteristics of human HCC HepG2 and Hep3b cell lines were studied with standard clonogenic assays, using standard linear-quadratic model and incomplete repair model to fit the dose-survival curves. The identical methods were also employed to investigate the biological effectiveness of irradiation protocols modeling clinical conventional fractionated external beam radiotherapy (EBRT, fraction delivery time 3 min) and IMRT with different prolonged fraction delivery time (15, 30, and 45 min). The differences of cell surviving fraction irradiated with different fraction delivery time were tested with paired t-test. Factors determining the impact of prolonged fraction delivery time on cell killing were analyzed.RESULTS: The α/β and repair half-time (T1/2) of HepG2and Hep3b were 3.1 and 7.4 Gy, and 22 and 19 min respectively. The surviving fraction of HepG2 irradiated modeling IMRT with different fraction delivery time was significantly higher than irradiated modeling EBRT and the cell survival increased more pronouncedly with the fraction delivery time prolonged from 15 to 45 min,while no significant differences of cell survival in Hep3b were found between different fraction delivery time protocols.CONCLUSION: The prolonged fraction delivery time modeling IMRT significantly decreased the cell killing in HepG2 but not in Hep3b. The capability of sub-lethal damage repair was the predominant factor determining the cell killing decrease. These effects, if confirmed by clinical studies, should be considered in designing IMRT treatments for HCC.
基金The project supported by Tianyuan Foundation for Mathematics under Grant No. 10626016 of National Natural Science Foundation of China, China Postdoctoral Science Foundation, Beijing Jiao-Wei Key Project under Grant No. KZ 200310028010, and National Natural Science Foundation of China under Grant No. 10375038
文摘Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given.
基金supported by the National Natural Science Foundation of China(No.81070544,81172450and 81070605)the Shanghai Municipal Education Commission Foundation(No.09YZ76)the Medical Engineering Cross-fund of Shanghai Jiaotong University(No.YG2011MS14).
文摘Ischemic priapism is a rare occurrence which can cause severe erectile dysfunction(ED)without timely treatment.This retrospective study reports our experience in treating prolonged ischemic priapism and proposes our further considerations.In this paper,a total of nine patients with prolonged ischemic priapism underwent one to three types of surgical shunts,including nine Winter shunts,two AI-Ghorab shunts and one Grayhack shunt.During the follow-up visit(after a mean of 21.11 months),all patients'postoperative characters were recorded,except one patient lost for death.Six postoperative patients accepted a 25-mg oral administration of sildenafil citrate.The erectile function of the patients was evaluated by their postoperative 5-item version of International Index of Erectile Function Questionnaire(IIEF-5),which were later compared with their premorbid scores.All patients had complete resolutions,and none relapsed.The resolution rate was 100%.Seven patients were resolved with Winter shunts,one with an AI-Ghorab shunt and one with a Grayhack shunt.The mean hospital stay was 8.22 days.There was only one urethral fistula,and the incidence of postoperative ED was 66.67%.Four patients with more than a 72-h duration of priapism had no response to the long-term phosphodiesterase type 5(PDE-5)inhibitor treatment.These results suggest that surgical shunts are an efficient approach to make the penis flaccid after prolonged priapism.However,the severe ED caused by prolonged duration is irreversible,and long-term PDE-5 inhibitor treatments are ineffective.Thus,we recommend early penile prosthesis surgeries for these patients.
文摘The microstructural evolution and consequent changes in strength and ductility of advanced NANOBAIN steel during prolonged isothermal heat-treatment stages were investigated. The microstructure and mechanical properties of nanostructured bainite were not expected to be influenced by extending the heat-treatment time beyond the optimum value because of the autotempering phenomenon and high tempering resistance. However, experimental results indicated that the microstructure was thermodynamically unstable and that prolonged austempering resulted in carbon depletion from high-carbon retained austenite and carbide precipitations. Therefore, austenite became thermally less stable and partially transformed into martensite during cooling to room temperature. Prolonged austempering did not lead to the typical tempering sequence of bainite, and the sizes of the microstructural constituents were independent of the extended heat-treatment times. This independence, in turn, resulted in almost constant ultimate tensile strength values. However, microstructural variations enhanced the yield strength and the hardness of the material at extended isothermal heat-treatment stages. Finally, although microstructural changes decreased the total elongation and impact toughness, considerable combinations of mechanical properties could still be achieved.
基金supported by grants to MQ from the National Key Research and Development Program of China (2020YFC2003301 and 2020YFC2007005)National Natural Science Foundation of China (81703252)+1 种基金Shanghai Committee of Science and Technology of China(19080503000)HW from the Public Welfare Technology Project of the Zhejiang Science Department(LGF18H170006)
文摘Purpose:This study aimed to evaluate the effectiveness of physical activity(PA)interrupting prolonged sitting(PS)on postprandial glycemia and insulin responses among adults.Methods:PubMed,EMBASE,Cochrane Library,Web of Science,CINAHL,PsycINFO,and the China National Knowledge Infrastructure databases were searched through September 30,2020.Randomized controlled trials(RCTs)that examined the effect of all forms of PA interrupting PS on postprandial glycemia and/or insulin responses among adults without chronic diseases were included in this study.The risk of bias of included studies was evaluated based on the Cochrane tool.A network meta-analysis was performed to estimate the summary standardized mean differences(SMDs)with 95%confidence intervals(95%CIs)with random effects.Results:Thirty crossover RCTs were included in our review.These RCTs included 9 types of interventions that interrupted PS.When compared to PS by itself,light-intensity PA intermittent interrupting(LPA-INT)PS and moderate-intensity PA intermittent interrupting(MPA-INT)PS significantly lowered postprandial glycemia(SMD=-0.46,95%CI:-0.70 to-0.21;SMD=-0.69,95%CI:-1.00 to-0.37,respectively)and significantly reduced postprandial insulin response(SMD=-0.46,95%CI:-0.66 to-0.26;SMD=-0.47,95%CI:-0.77 to-0.17,respectively).Results of the clustered ranking plot indicated that MPA-INT was the most effective intervention in lowering postprandial glycemia and insulin responses.Conclusion:Replacing PS with MPA-INT or LPA-INT has a positive effect in reducing postprandial glycemia and insulin responses,with MPA-INT being the optimal intervention strategy.
基金The authors greatly appreciate the professional and earnest review made by the anonymous reviewers which for sure improved the quality of our manuscript.This work was supported by the National Key R&D Program of China(Grant Nos.2018YFC1505905&2018YFC1505803)the National Natural Science Foundation of China(Grant Nos.42088101,41805048 and 41875069)Tim LI was supported by NSF AGS-1643297 and NOAA Grant NA18OAR4310298.
文摘An exceptionally prolonged heavy snow event(PHSE)occurred in southern China from 10 January to 3 February 2008,which caused considerable economic losses and many casualties.To what extent any dynamical model can predict such an extreme event is crucial for disaster prevention and mitigation.Here,we found the three S2S models(ECMWF,CMA1.0 and CMA2.0)can predict the distribution and intensity of precipitation and surface air temperature(SAT)associated with the PHSE at 10-day lead and 10−15-day lead,respectively.The success is attributed to the models’capability in forecasting the evolution of two important low-frequency systems in the tropics and mid-latitudes[the persistent Siberian High and the suppressed phase of the Madden−Julian Oscillation(MJO)],especially in the ECMWF model.However,beyond the 15-day lead,the three models show almost no skill in forecasting this PHSE.The bias in capturing the two critical circulation systems is responsible for the low skill in forecasting the 2008 PHSE beyond the 15-day lead.On one hand,the models cannot reproduce the persistence of the Siberian High,which results in the underestimation of negative SAT anomalies over southern China.On the other hand,the models cannot accurately capture the suppressed convection of the MJO,leading to weak anomalous southerly and moisture transport,and therefore the underestimation of precipitation over southern China.The Singular Value Decomposition(SVD)analyses between the critical circulation systems and SAT/precipitation over southern China shows a robust historical relation,indicating the fidelity of the predictability sources for both regular events and extreme events(e.g.,the 2008 PHSE).
