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Feasibility and clinical benefits of the double-ProGlide technique for hemostasis after cryoballoon atrial fibrillation ablation with uninterrupted oral anticoagulants 被引量:2
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作者 Jia-Yin SUN Chang-Bo XUAN +7 位作者 Hai-Liang YU Hai-Yang WANG Hong-Ya HAN Zhi-Ming ZHOU De-An JIA Dong-Mei SHI Yu-Jie ZHOU Shi-Wei YANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第4期268-275,共8页
OBJECTIVE To access the efficacy and safety of the double-ProGlide technique for the femoral vein access-site closure in cryoballoon ablation with uninterrupted oral anticoagulants(OAC),and its impact on the electroph... OBJECTIVE To access the efficacy and safety of the double-ProGlide technique for the femoral vein access-site closure in cryoballoon ablation with uninterrupted oral anticoagulants(OAC),and its impact on the electrophysiology laboratory time as well as hospital stay after the procedure in this observational study.METHODS Patients with atrial fibrillation undergoing cryoballoon ablation with uninterrupted OAC at Department of Cardiology,Beijing Anzhen Hospital,Capital Medical University,Beijing,China from May 2019 to May 2021 were enrolled in this study.From October 2020,double-ProGlide technique was consistently used for hemostasis(ProGlide group),and before that conventional manual compression was utilized(manual compression group).The occurrence of vascular and groin complications was accessed during the hospital stay and until the three-month follow-up.RESULTS A total of 140 participants(69.30%of male,mean age:59.21±10.29 years)were evaluated,70 participants being in each group.Immediate hemostasis was achieved in all the patients with ProGlide closure.No major vascular complications were found in the ProGlide group while two major vascular complications were occurred in the manual compression group.The incidence of any groin complication was obviously higher in subjects with manual compression than patients with ProGlide devices(15.71%vs.2.86%,P=0.009).In addition,compared with the manual compression group,the ProGlide group was associated with significantly shorter total time in the electrophysiology laboratory[112.0(93.3–128.8)min vs.123.5(107.3–158.3)min,P=0.006],time from sheath removal until venous site hemostasis[3.8(3.4–4.2)min vs.8.0(7.6–8.5)min,P<0.001],bed rest time[8.0(7.6–8.0)h vs.14.1(12.0–17.6)h,P<0.001]and hospital stay after the procedure[13.8(12.5–17.8)h vs.38.0(21.5–41.0)h,P<0.001].CONCLUSIONS Utilization of the double-ProGlide technique for hemostasis after cryoballoon ablation with uninterrupted OAC is feasible and safe,which has the clinical benefit in reducing the total electrophysiology laboratory time and the hospital stay length after the procedure. 展开更多
关键词 BALLOON interrupted CLOSURE
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Interrupted Time Series Analysis of Military and Civilian Regimes in Nigeria: A Statistical Evidence from Gross Domestic Product (GDP)
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作者 Desmond Chekwube Bartholomew Geoffrey Uzodinma Ugwuanyim +1 位作者 Ukamaka Cynthia Orumie Francis Attah Egwumah 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期635-660,共26页
Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources... Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources are used in the economy. Higher taxes, fees, and greater regulations can stymie businesses or entire industries and the resulting impact is reflected on the country’s economy status (strong or weak). The growth rate of GDP is often used as an indicator of the general health of the economy. In broad terms, an increase in real GDP is interpreted as a sign that the economy is doing well. So it is important to study and pay more attention to country’s GDP growth rate. In this paper, an intervention analysis approach was applied to Nigeria GDP data in order to evaluate the performances of military and civilian rules in the country. Data on Nigeria GDP were collected and subjected to interrupted (intervention) time series model. Based on the Alkaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and sigma<sup>2</sup> values, the interrupted time series model ARIMA (1, 1, 0) with exogenous variables (per capita per capita GDP, intervention, year and yearAfter) was identified as the best model amongst other competing models. It was observed that the intervention (civilian rule) was significant at the 10% level of significance in increasing the Nigeria GDP by 10B US$ on the average since 2005 till 2021 while controlling for the effects of other determinants. Also, the ARIMA (1, 1, 0) forecasts indicate that the Nigeria GDP will continue increasing during the civilian rule. As a result, changing from military rule to civilian rule in Nigeria significantly increased the GDP of the country. 展开更多
关键词 ARIMA FORECAST Gross Domestic Product NIGERIA INTERVENTION interrupted Time Series
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Interrupted Time Series Analysis of Military and Civilian Regimes in Nigeria: A Statistical Evidence from Gross Domestic Product (GDP)
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作者 Desmond Chekwube Bartholomew Geoffrey Uzodinma Ugwuanyim +1 位作者 Ukamaka Cynthia Orumie Francis Attah Egwumah 《Open Journal of Statistics》 2023年第4期635-660,共26页
Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources... Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources are used in the economy. Higher taxes, fees, and greater regulations can stymie businesses or entire industries and the resulting impact is reflected on the country’s economy status (strong or weak). The growth rate of GDP is often used as an indicator of the general health of the economy. In broad terms, an increase in real GDP is interpreted as a sign that the economy is doing well. So it is important to study and pay more attention to country’s GDP growth rate. In this paper, an intervention analysis approach was applied to Nigeria GDP data in order to evaluate the performances of military and civilian rules in the country. Data on Nigeria GDP were collected and subjected to interrupted (intervention) time series model. Based on the Alkaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and sigma<sup>2</sup> values, the interrupted time series model ARIMA (1, 1, 0) with exogenous variables (per capita per capita GDP, intervention, year and yearAfter) was identified as the best model amongst other competing models. It was observed that the intervention (civilian rule) was significant at the 10% level of significance in increasing the Nigeria GDP by 10B US$ on the average since 2005 till 2021 while controlling for the effects of other determinants. Also, the ARIMA (1, 1, 0) forecasts indicate that the Nigeria GDP will continue increasing during the civilian rule. As a result, changing from military rule to civilian rule in Nigeria significantly increased the GDP of the country. 展开更多
关键词 ARIMA FORECAST Gross Domestic Product NIGERIA INTERVENTION interrupted Time Series
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Does Monetary Support Increase the Number of Scientific Papers? An Interrupted Time Series Analysis 被引量:1
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作者 Yasar Tonta 《Journal of Data and Information Science》 CSCD 2018年第1期19-38,共20页
Purpose: One of the main indicators of scientific production is the number of papers published in scholarly journals. Turkey ranks 18 th place in the world based on the number of scholarly publications. The objective ... Purpose: One of the main indicators of scientific production is the number of papers published in scholarly journals. Turkey ranks 18 th place in the world based on the number of scholarly publications. The objective of this paper is to find out if the monetary support program initiated in 1993 by the Turkish Scientific and Technological Research Council(TüB?TAK) to incentivize researchers and increase the number, impact, and quality of international publications has been effective in doing so.Design/methodology/approach: We analyzed some 390,000 publications with Turkish affiliations listed in the Web of Science(Wo S) database between 1976 and 2015 along with about 157,000 supported ones between 1997 and 2015. We used the interrupted time series(ITS) analysis technique(also known as "quasi-experimental time series analysis" or "intervention analysis") to test if TüB?TAK's support program helped increase the number of publications. We defined ARIMA(1,1,0) model for ITS data and observed the impact of TüB?TAK's support program in 1994, 1997, and 2003(after one, four and 10 years of its start, respectively). The majority of publications(93%) were full papers(articles), which were used as the experimental group while other types of contributions functioned as the control group. We also carried out a multiple regression analysis.Findings: TüB?TAK's support program has had negligible effect on the increase of the number of papers with Turkish affiliations. Yet, the number of other types of contributions continued to increase even though they were not well supported, suggesting that TüB?TAK's support program is probably not the main factor causing the increase in the number of papers with Turkish affiliations.Research limitations: Interrupted time series analysis shows if the "intervention" has had any significant effect on the dependent variable but it does not explain what caused the increase in the number of papers if it was not the intervention. Moreover, except the"intervention", other "event(s)" that might affect the time series data(e.g., increase in the number of research personnel over the years) should not occur during the period of analysis, a prerequisite that is beyond the control of the researcher.Practical implications: TüB?TAK's "cash-for-publication" program did not seem to have direct impact on the increase of the number of papers published by Turkish authors, suggesting that small amounts of payments are not much of an incentive for authors to publish more. It might perhaps be a better strategy to concentrate limited resources on a few high impact projects rather than to disperse them to thousands of authors as "micropayments." Originality/value: Based on 25 years' worth of payments data, this is perhaps one of the first large-scale studies showing that "cash-for-publication" policies or "piece rates" paid to researchers tend to have little or no effect on the increase of researchers' productivity. The main finding of this paper has some implications for countries wherein publication subsidies are used as an incentive to increase the number and quality of papers published in international journals. They should be prepared to consider reviewing their existing support programs(based usually on bibliometric measures such as journal impact factors) and revising their reward policies. 展开更多
关键词 Performance-based research funding systems Publication subsidies Publication support programs interrupted time series analysis
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Skin-Adhesive Tape versus Interrupted Suture in Episiotomy Skin Repair: Randomized Control Trial 被引量:1
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作者 Ahmed Sherif Maged El-Shourbagy 《Open Journal of Obstetrics and Gynecology》 2020年第2期254-263,共10页
Introduction: The ideal method for perineal repair should be quick, easy to perform and preferably, with minimal pain. Aim: To compare skin adhesive tape and interrupted?absorbable subcuticular suture for episiotomy r... Introduction: The ideal method for perineal repair should be quick, easy to perform and preferably, with minimal pain. Aim: To compare skin adhesive tape and interrupted?absorbable subcuticular suture for episiotomy repair after birth as regard postoperative pain, skin closure time and wound infection. Design: Prospective double-blinded randomized controlled trial. Methods: Three-hundred qualified patients were equally distributed between two groups. Group 1 underwent skin repair with skin adhesive tape, while group 2 underwent the currently traditional method for perineal repair by interrupted suture. Pain was evaluated at 2, 4, 6 and 12 hours after birth then daily until one week using Wong-Baker faces pain rating scale with verbal expression for pain intensity as primary outcome. Skin closure time and wound infection were also evaluated as secondary outcomes. Results: Statistically significant difference in pain was?found at 4 and 6 hours, and 3,?4,?5 and 7 days after perineal repair in favor of the adhesive tape group (p = 0.04 and 0.02 respectively) (p = 0.002, 0.002, 0.003 and 0.001 respectively). No statistically significant difference was found in skin closure time between both groups, and no cases of wound infection occurred in both groups (p = 0.3). Conclusion: Skin adhesive tape may be superior to skin suturing in decreasing pain resulting from perineal repair after birth;however, further studies are needed to assess long-term effects, calculate costs and accurately measure patients’ satisfaction, which were not addressed in this study. 展开更多
关键词 SKIN Adhesive TAPE interrupted SUTURES EPISIOTOMY SKIN Repair Pain
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An Interrupted Time Series Analysis of COVID-19 Positivity before, during and after Lockdown in Four States of India 被引量:1
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作者 Shailaja Tetali Guru Rajesh Jammy +2 位作者 Edwin Sam Asirvatham Bogam Ranjeeth Kumar Lincoln Priyadarshi Choudhury 《Open Journal of Epidemiology》 2021年第1期47-55,共9页
<strong>Objectives:</strong> The objective of this study was to examine the impact of large scale non-pharmaceutical interventions on COVID-19 pandemic. <strong>Methods:</strong> We used interr... <strong>Objectives:</strong> The objective of this study was to examine the impact of large scale non-pharmaceutical interventions on COVID-19 pandemic. <strong>Methods:</strong> We used interrupted time series analysis (ITS), a quasi-experimental model to evaluate the effect of interventions in four states of India by comparing the COVID-19 positivity before lockdown, during lockdown and opening-up period. <strong>Results:</strong> The positivity in all the four states declined during lockdown and the trends reversed soon after the lockdown measures were relaxed as the states opened-up. The rate of reduction of positivity was significantly different between states. Between the lockdown and opening-up period, an increase in positivity was recorded in all the states with significant variation between states. <strong>Conclusion:</strong> The analysis provides conclusive evidence that the lockdown measures had a positive effect in reducing the burden of COVID-19 and establishes a causal relationship. 展开更多
关键词 CAUSALITY interrupted Time Series COVID-19 Impact Evaluation
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Isolated interrupted aortic arch in an adult:A case report
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作者 Shu-Wen Dong Duo-Duo Di Guan-Xun Cheng 《World Journal of Clinical Cases》 SCIE 2021年第4期992-998,共7页
BACKGROUND Interrupted aortic arch(IAA)is a rare congenital heart disease defined by an interruption of the lumen and anatomical continuity between the ascending and descending major arteries.It is usually found withi... BACKGROUND Interrupted aortic arch(IAA)is a rare congenital heart disease defined by an interruption of the lumen and anatomical continuity between the ascending and descending major arteries.It is usually found within a few hours or days of birth.Without surgery,the chances of survival are low.If IAA patients have an effective collateral circulation established,they can survive into adulthood.However,IAA in adults is extremely rare,with few reported cases.CASE SUMMARY A 27-year-old woman presented with a 6-year history of progressively worsening shortness of breath and chest tightness on exertion.She had cyanotic lips and clubbing of the fingers.A transthoracic echocardiogram revealed an enlarged heart and dilation of the main pulmonary artery.There was an abnormal 9 mm passage between the descending aorta and pulmonary artery.The ventricular septal outflow tract had a 14 mm defect.Doppler ultrasound suggested a patent ductus arteriosus and computed tomographic angiography showed the absence of the aortic arch.The diagnoses were ventricular septal defect,patent ductus arteriosus,and definite interruption of the aortic arch.Although surgical correction was recommended,the patient declined due to the surgical risks and was treated with medications to reduce pulmonary artery pressure and treat heart failure.Her condition has been stable for 12 mo of follow-up.CONCLUSION Although rare,IAA should be considered in adults with refractory hypertension or unexplained congestive heart failure. 展开更多
关键词 interrupted aortic arch Diagnostic imaging Multimodal imaging Patent ductus arteriosus Ventricular septal defect Case report
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Difference and similarity between type A interrupted aortic arch and aortic coarctation in adults:Two case reports
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作者 Si-Xie Ren Qian Zhang +1 位作者 Pan-Pan Li Xiao-Dong Wang 《World Journal of Clinical Cases》 SCIE 2022年第11期3472-3477,共6页
BACKGROUND Aortic coarctation(CoA)is usually confused with interrupted aortic arch(IAA),especially adult type A interrupted aortic arch,due to their similar anatomical location.Although the main difference between the... BACKGROUND Aortic coarctation(CoA)is usually confused with interrupted aortic arch(IAA),especially adult type A interrupted aortic arch,due to their similar anatomical location.Although the main difference between them is whether arterial lumen exhibits continuity or not,the clinical manifestations are similar and connection exists between them.Adult type A IAA is considered as an extreme form of CoA,which is complete discontinuity of aortic function and lumen caused by degenerative arterial coarctation.This paper reports two cases(interrupted aortic arch and severe aortic coarctation)to analyze the difference and similarity between them.CASE SUMMARY The two cases of patients presented with hypertension for many years.Computed tomography angiography showed that the aortic arch and descending aorta were discontinuous or significantly narrowed with extensive collateral flow.The IAA patient refused surgical treatment and blood pressure could be controlled with drugs.While the CoA patient underwent stent implantation because of uncontrollable hypertension,the blood flow recovered smoothly and the blood pressures at both ends of the stenosis returned to normal after surgery.CONCLUSION Adult type A IAA and CoA have difference and similarity,and type A IAA is associated with CoA to a certain extent.The treatment method should be chosen based on the patient's clinical symptoms rather than the severity of the lesion. 展开更多
关键词 interrupted aortic arch Aortic coarctation Computed tomography Angiogram Case report
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Natural History of Kawashima Palliation in Single-Ventricle and Interrupted Inferior Vena Cava Heart Disease in China 11 Years Result
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作者 Yajuan Zhang Jun Yan +4 位作者 Qiang Wang Shoujun Li Jing Sun Shuo Dong Jiachen Li 《Congenital Heart Disease》 SCIE 2021年第4期383-392,共10页
Background:The long-term outcomes of patients treated with a Kawashima procedure and keeping the antegrade pulmonary blood flow(AnPBF)in single-ventricle(SV)and interrupted inferior vena cava(IVC)heart disease is stil... Background:The long-term outcomes of patients treated with a Kawashima procedure and keeping the antegrade pulmonary blood flow(AnPBF)in single-ventricle(SV)and interrupted inferior vena cava(IVC)heart disease is still uncertain as yet.Methods:We investigated 18 patients who underwent the Kawashima procedure with SV physiology and an interrupted IVC between January 2009 and June 2018,perioperative,operative and postoperative characteristics were recorded.Results:A total of 18 patients underwent the Kawashima procedure at a median age of 2.7 years(range 0.5–24.7 years),of which 12(66.7%)were male and 6(33.3%)were female.The mean saturation was 76.2±8.5%in preoperative period and 94.2±2.2%in postoperative period.All patients had kept AnPBF.The median duration of mechanical ventilation was 12 h(range 2.5–22.5 h)and the median duration of pleural drainage was 5 days(range 2–27 days).The median hospital stay was 9 days(range 6–70 days).There was no operative death and no mortality was seen in early postoperative period.Follow-up was 100%completed,with an average follow-up period of 6.1±2.7 years(range 1–11 years).4 patients died during the follow-up.The overall 5 and 10 years’survival rates estimated by Kaplan-Meier method were 88%and 68%,respectively.Although there were no significant differences in the duration of postoperative follow-up between the death group and the survival group(p>0.05),the major systemic ventricular end-diastolic diameter(SVEDD)(p=0.018)and the degree of AVVR(p=0.001)showed significant difference between the two groups.The diameters of main pulmonary artery showed significant growth in both the death group(p=0.015)and the survival group(p=0.012)over time.SVEDD had no significant increase in the survival group(p=0.665)but was significantly larger in the death group(p=0.014).Multivariable risk factors of late mortality in patients treated with Kawashima procedure were follow-up AVVR(p=0.044;HR:3.124;95%CI:1.030–9.473)and SVEDD(p=0.031;HR:9.766;95%CI:1.226–77.8).14 patients(100%)were all in New York Heart Association(NYHA)functional class I and the mean saturation was 93±2%at last follow-up.Only one patient finished Fontan completion.Conclusions:The Kawashima procedure with AnPBF can be safely performed with acceptable early and long outcomes.Although some previous studies have shown the risk of pulmonary arteriovenous malformations(PAVMS)after Kawashima procedure in the mid-and long-term,our findings are in contradiction with it.No PAVMs occurred in all the survivors.Kawashima procedure with open AnPBF may be a good option for unsuitable Fontan candidates. 展开更多
关键词 interrupted inferior vena cava single ventricle Kawashima palliation antegrade pulmonary blood flow(AnPBF) pulmonary arteriovenous malformations(PAVMS)
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Experimental Study of Heat Transfer to Flowing Air inside a Circular Tube with Longitudinal Continuous and Interrupted Fins
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作者 Saad A. El-Sayed Sayed A. EL-Sayed Mohamed M. Saadoun 《Journal of Electronics Cooling and Thermal Control》 2012年第1期1-16,共16页
Experimental investigations have been performed to determine the detailed module-by-module pressure drop and heat transfer coefficient of turbulent flow inside a circular finned tube. The tubes are provided with longi... Experimental investigations have been performed to determine the detailed module-by-module pressure drop and heat transfer coefficient of turbulent flow inside a circular finned tube. The tubes are provided with longitudinal fins continuous or interrupted in the stream wise direction by arranging them both in a staggered and in-line manner. Experiments are carried out for two different fin geometries, with two numbers of fins (N = 6 and 12). All tested finned tubes have 16 modules each with length equal to the tube diameter (L = D = 30 mm). The thermal boundary condition considered here, is a uniform heat flux. The module-by-module heat transfer coefficient is found to vary only in the first modules, and then attained a constant thermally periodic fully developed value after eight to twelve modules. The results also showed that in the periodic hydrodynamic fully developed region, the value of the pressure drop along the tube with continuous fins is greater than that of the in-line arrangement, and lower than that of the staggered arrangement. Furthermore, the results showed that in the periodic fully developed region, the tube with continuous fins produces a greater value of the heat transfer coefficients than that the tube with interrupted fins, especially through a high range of Reynolds number (5 × 104 > Re > 2 × 104). The tube with Staggered arrangement of fins produces a greater value of the heat transfer coefficient than the tube with continuous fins and the in-line arrangement finned tube at low Reynolds number (Re < 1.2 × 104).). It was found that the fins efficiency is greater than 90 percent;in the worst case (maximum Reynolds number with continuous fins tube). 展开更多
关键词 Internal FLOW TURBULENT FLOW Heat Transfer interrupted and CONTINUOUS FINS FIN Analysis
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Interrupted Etanercept Therapy: A New Case Report
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作者 Waqas S. Abdulwahhab Alaa S. Mehair 《Journal of Cosmetics, Dermatological Sciences and Applications》 2021年第2期71-75,共5页
Psoriasis is a chronic, immune-mediated, inflammatory disease with a high prevalence in the general population (2%). The anti-tumor necrosis factor receptor etanercept is Food and Drug Administration (FDA) approved fo... Psoriasis is a chronic, immune-mediated, inflammatory disease with a high prevalence in the general population (2%). The anti-tumor necrosis factor receptor etanercept is Food and Drug Administration (FDA) approved for the treatment of moderate-to-severe plaque psoriasis. Both continuous and interrupted etanercept therapy is effective and well-tolerated. This report <strong>aims</strong> to document a new case presentation of psoriasis on intermittent etanercept injection throughout 36 weeks with long-lasting sustained efficacy and no risk factor. <strong>Case Report</strong>: A 39-year-old adult male patient with long-standing chronic plaque psoriasis for 15 years duration without joint involvement started loading dose treatment of etanercept injection in whom due to his work circumstances not taken maintenance therapy and showed-up at the clinic after 36 weeks from first induction therapy when partial relapse of psoriatic lesions appear in last week with continued improvement when reintroducing loading treatment on followed-up over the next 36 weeks. <strong>Conclusion</strong>: Intermittent etanercept therapy considers effective for 36 weeks with prolonging sustained efficacy and without adverse effect. 展开更多
关键词 ADHERENCE Anti-Tumor Necrosis Factor-Alpha (Anti-TNF-α) ETANERCEPT interrupted Therapy PSORIASIS
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Precipitation behavior of γ′ phase in superalloy FGH96 under interrupted cooling test 被引量:2
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作者 Heng-San Liu Lin Zhang +3 位作者 Xin-Bo He Xuan-Hui Qu Zhou Li Guo-Qing Zhang 《Rare Metals》 SCIE EI CAS CSCD 2013年第6期560-563,共4页
The precipitation behavior of γ′ phase,under various interrupt cooling tests after 1170℃,solution treatment was examined.The results indicate that the size of secondary γ′ precipitates increases with the decrease... The precipitation behavior of γ′ phase,under various interrupt cooling tests after 1170℃,solution treatment was examined.The results indicate that the size of secondary γ′ precipitates increases with the decrease of interrupt temperature,and the shape changes from spherical to butterfly like.The fine tertiary γ′ can form either during the post cool air quenching at high interrupt-temperatures,or during the specified 5℃ min-1cooling.Air quenching at high temperatures cannot suppress further nucleation of tertiary γ′ phase. 展开更多
关键词 Powder METALLURGY Ni-base SUPERALLOY INTERRUPT COOLING Precipitation
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Research on arc root stagnation when small current is interrupted in self-excited circuit breaker 被引量:3
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作者 彭世东 李静 +2 位作者 曹云东 黄翀阳 刘树鑫 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第11期14-25,共12页
The self-excited DC air circuit breaker(SE-DCCB)has been widely used in urban rail transit due to its excellent stability.It can realize forward and reverse interruption,but has difficulty interrupting small currents ... The self-excited DC air circuit breaker(SE-DCCB)has been widely used in urban rail transit due to its excellent stability.It can realize forward and reverse interruption,but has difficulty interrupting small currents due to the phenomenon of arc root sticking at the entrance of the arc chamber in the splitting process,which is known as arc root stagnation.A coupling model of the self-excited magnetic field and magnetohydrodynamics is established for the SE-DCCB with the traditional structure.The magnetic field,temperature and airflow distribution in the arc chamber are investigated with an interrupting current of 150 A.The simulation results show that the direction and magnitude of the magnetic blowout force are the dominant factors in the arc root stagnation.The local high temperature of the arc chamber due to arc root stagnation increases the obstruction effect of the airflow vortex on the arc root movement,which significantly increases the arc duration time of small current interruption.Based on the research,the structure of the magnetic conductance plate of the actual product is improved,which can improve the direction and magnitude of the magnetic blowout force at the arc root so as to restrain the development of the airflow vortex effectively and solve the problem of arc root stagnation when the small current is interrupted.The simulation results show that the circuit breaker with improved structure has a better performance for a small current interruption range from 100 A to 350 A. 展开更多
关键词 self-excited DC air circuit breaker small current interruption magnetic blowout force arc root stagnation airflow vortex
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The Electroluminescence Characterization of Poly(p-phenyleneethynylene)——The π-conjugated Backbone Interrupted by a Butylene Unit
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作者 NIU Jun-feng and YANG Mu-jie ** Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第1期88-92,共5页
π -Conjugated poly( p -phenyleneethynylene) with the interruption of the conjugation by a butylene unit was synthesized. Its absorption, PL and EL spectra were investigated respectively. The spectral peaks shifted to... π -Conjugated poly( p -phenyleneethynylene) with the interruption of the conjugation by a butylene unit was synthesized. Its absorption, PL and EL spectra were investigated respectively. The spectral peaks shifted to the higher energy side with the interruption of the conjugation lengths. The model compound was synthesized, by which the results were proved. The thermal characteristics of the polymer was determined by DSC and TGA, indicating that the polymer has a good thermal stability. The electroluminescence(EL) in the green region of the spectrum with a maximum at 500 nm was observed from the polymer films sandwiched between indium-tin-oxide and an Al electrode. 展开更多
关键词 Electroluminescence Poly(2 5-dialkoxy-p-phenyleneethynylene) INTERRUPTION
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C-Aryl Glycosylation via Interrupted Pummerer Rearrangement
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作者 Jiagen Li Xuefeng Jiang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第21期2843-2847,共5页
C-aryl glycosides are an important kind of carbohydrate derivatives for drug discovery,due to their distinctive attributes of resistance to hydrolysis from enzymes.Herein,C-aryl glycosylation was established for the s... C-aryl glycosides are an important kind of carbohydrate derivatives for drug discovery,due to their distinctive attributes of resistance to hydrolysis from enzymes.Herein,C-aryl glycosylation was established for the synthesis of 2-sulfur C-aryl glycals and 1,2-dihydrobenzofuran-fused C-aryl glycosides via interrupted Pummerer process,featured with sulfonium-tethered[3,3]-sigmatropic rearrangement between sulfoxide glycals and phenols.This protocol offers a broad substrate scope with diverse glycosyl and phenols.Dapagliflozin,Empagliflozin,and Ipragliflozin analogs were straightforward achieved,respectively. 展开更多
关键词 GLYCAL GLYCOSYLATION interrupted pummerer REARRANGEMENT SULFOXIDE Carbohydrates C-GLYCOSIDES Drug discovery
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Mastering air combat game with deep reinforcement learning
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作者 Jingyu Zhu Minchi Kuang +3 位作者 Wenqing Zhou Heng Shi Jihong Zhu Xu Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期295-312,共18页
Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem ... Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural networks.Plasticity loss is the difficulty of learning new knowledge after the network has converged.To this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning methods.The motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a guide.Furthermore,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be realized.In addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an emergency.When the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions again.Using the interruption mechanism can significantly improve the performance of the agent.To simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data throughput.The experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper. 展开更多
关键词 Air combat MCLDPPO Interruption mechanism Digital twin Distributed system
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Modulated-ISRJ rejection using online dictionary learning for synthetic aperture radar imagery
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作者 WEI Shaopeng ZHANG Lei +1 位作者 LU Jingyue LIU Hongwei 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期316-329,共14页
In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes consid... In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes considerable coherence with the SAR transmission waveform together with periodical modulation patterns.This paper develops an MISRJ suppression algorithm for SAR imagery with online dictionary learning.In the algorithm,the jamming modulation temporal properties are exploited with extracting and sorting MISRJ slices using fast-time autocorrelation.Online dictionary learning is followed to separate real signals from jamming slices.Under the learned representation,time-varying MISRJs are suppressed effectively.Both simulated and real-measured SAR data are also used to confirm advantages in suppressing time-varying MISRJs over traditional methods. 展开更多
关键词 synthetic aperture radar(SAR) modulated interrupt sampling jamming(MISRJ) online dictionary learning
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Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and Switchable Domino Reactions of a-Substituted Activated Olefins with Formaldehyde and Mechanism Elucidation
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作者 Jing Gu Ben-Xian Xiao +2 位作者 Qin Ouyang Wei Du Ying-Chun Chen 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2019年第2期155-160,共6页
Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type... Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism. 展开更多
关键词 Phosphine-Catalyzed interrupted Morita-Baylis-Hillman Reaction SWITCHABLE Domino Reactions of a-Substituted Activated Olefins FORMALDEHYDE MECHANISM ELUCIDATION
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A CHURCH INTERRUPTED
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作者 YAN WEI 《Beijing Review》 2006年第22期30-31,共2页
The history of a German-built Protestant church in Qingdao offers a sketch of Christianity's development in modern China Li Hong's father used to wedge his Bible into a thick mat so it wouldn't be confisca... The history of a German-built Protestant church in Qingdao offers a sketch of Christianity's development in modern China Li Hong's father used to wedge his Bible into a thick mat so it wouldn't be confiscated. That was during the Cultural Revolution from 1966 to 1976, when all religions were suppressed, she said. 展开更多
关键词 LI In A CHURCH interrupted
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Wound dehiscence with continuous versus interrupted mass closure of transverse incisions in children with absorbable suture:a randomized controlled trial
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作者 Safwan Khan Muhammad Saleem Nabila Talat 《World Journal of Pediatric Surgery》 2019年第2期9-14,共6页
Introduction Numerous meta-analyses done on adults suggest superiority of continuous mass closure technique,but any such study does not exist for the pediatric age group.The results in adults cannot be applied to pedi... Introduction Numerous meta-analyses done on adults suggest superiority of continuous mass closure technique,but any such study does not exist for the pediatric age group.The results in adults cannot be applied to pediatrics because of numerous physiologic and anatomic differences.Methods This is a single-blinded,randomized controlled trial,1:1 parallel groups,that compares the frequency of dehiscence between the interrupted and continuous mass closure techniques for transverse incisions in pediatric patients.The age range was from birth to 12 years.We sampled 350 patients undergoing emergency or elective exploratory laparotomies in our pediatric surgery unit.Blocked randomization was used and only the patients remained blinded during the intervention.One group was closed with interrupted mass closure(group A)and the other group with continuous mass closure technique(group B).We had to drop 50 patients for not meeting the inclusion criteria.results The wound dehiscence rate for group A was 1.34%(4 patients)and for group B was 3.0%(9 patients).Significance was calculated usingχ^(2)(p<0.156).The global wound dehiscence rate was 4.34%(13 patients).The maximum number of patients dehisced on the fifth postoperative day,while the range was 4-11 days.The only statistically significant confounding factor was wound classification(p<0.002).Discussion Statistically there is no significant difference between interrupted and continuous mass closures techniques in terms of wound dehiscence.The dirty wounds are at a maximum risk of developing wound dehiscence irrespective of the technique used.We need to strictly adhere to the basic principles of closure especially when dealing with dirty wounds.trial registration number TCTR20150318001. 展开更多
关键词 WOUND CLOSURE interrupted
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