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Pre-and post-selected measurements with coupling-strength-dependent modulation
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作者 Zhaoxue Li Jiangdong Qiu +5 位作者 Linguo Xie Lan Luo Xiong Liu Zhiyou Zhang Changliang Ren JingLei Du 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第3期135-140,共6页
Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable... Pre-and post-selected(PPS) measurement, especially the weak PPS measurement, has been proved to be a useful tool for measuring extremely tiny physical parameters. However, it is difficult to retain both the attainable highest measurement sensitivity and precision with the increase of the parameter to be measured. Here, a modulated PPS measurement scheme based on coupling-strength-dependent modulation is presented with the highest sensitivity and precision retained for an arbitrary coupling strength. This idea is demonstrated by comparing the modulated PPS measurement scheme with the standard PPS measurement scheme in the case of unbalanced input meter. By using the Fisher information metric, we derive the optimal pre-and post-selected states, as well as the optimal coupling-strength-dependent modulation without any restriction on the coupling strength. We also give the specific strategy of performing the modulated PPS measurement scheme, which may promote practical application of this scheme in precision metrology. 展开更多
关键词 modulated pre-and post-selected MEASUREMENTS FISHER information metric unbalanced input METER
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ROLE OF TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN PRE-AND POST-PERCUTANEOUS BALLOON MITRAL VALVULOPLASTY
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作者 李守平 杨浣宜 +1 位作者 刘汉英 戴汝平 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第12期19-24,共6页
Transesophageal echocardiogram (TEE) was performed in 33 consecutive patients with both rheumatic mitral stenosis and chronic atrial fibrillation to evaluate tfae usefulness of this technique for the detection of left... Transesophageal echocardiogram (TEE) was performed in 33 consecutive patients with both rheumatic mitral stenosis and chronic atrial fibrillation to evaluate tfae usefulness of this technique for the detection of left atrial thrombi, mitral regurgitation before percutaneous balloon mitral valvuloplasty and iatrogenic atrial septal defect after the procedure. TEE correctly identified thrombi in 10 (30%) patients and significant mitral regurgitation in 5 patients who underwent surgical intervention. The remaining 18 patients underwent percutaneous balloon mitral valvuloplasty without evidence of systemic embolic event and obtained adequate outcome. Transesophageal color doppler echocardiography demostrated left-o-ight shunting flow through atrial septum in 5 of 7(71%) patients 3 days after the procedure and repeated TEE in 2 of these 5 patients showed no shunting after 6 months. In conclusion, TEE plays a definite role in the selection of patients for balloon mitral valvuloplasty and assessment of iatrogenic atrial septal defect. 展开更多
关键词 TTE In PBMV ROLE OF TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN pre-and POST-PERCUTANEOUS BALLOON MITRAL VALVULOPLASTY
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Analysis of groundwater level trend in Jakham River Basin of Southern Rajasthan 被引量:2
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作者 Vinay Kumar Gautam Mahesh Kothari +2 位作者 P.K.Singh S.R.Bhakar K.K.Yadav 《Journal of Groundwater Science and Engineering》 2022年第1期1-9,共9页
Groundwater accounts for about half of the water use for irrigation in India.The fluctuation pattern of the groundwater level is examined by observing rainfall replenishment and monitoring wells.The southern part of R... Groundwater accounts for about half of the water use for irrigation in India.The fluctuation pattern of the groundwater level is examined by observing rainfall replenishment and monitoring wells.The southern part of Rajasthan has experienced abrupt changes in rainfall and has been highly dependent on groundwater over decades.This study presents the impact of over-dependence on groundwater usage for irrigation and other purposes,spatially and temporally.Hence,the objective of this study is to examine the groundwater level trend by using statistical analysis and geospatial technique.Rainfall factor was also studied in groundwater level fluctuation during 2009-2019.To analyze the influence of each well during recharge or withdrawal of groundwater,thiessien polygonswere generated from them.In the Jakham River basin,75 wells have been identified for water level trend study using the Mann-Kendall statistical test.The statistics of trend analysis show that 15%wells are experiencing water level decline in pre-monsoon,while very low percentage of wells have such trend during post-monsoon season.The average rate of water level decline is 0.245 m/a in pre-monsoon and 0.05 m/a in post-monsoon.The aquifer recharge potential is also decreasing by year.it is expected that such type of studies will help the policy makers to adopt advanced management practices to ensure sustainable groundwater resource management. 展开更多
关键词 Groundwater Trend analysis RAINFALL Kendal tau Slope p value RECHARGE pre-and postmonsoon
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High-Capacity Transport Associated with Pre- and Post-Haulage in Intermodal Road-Rail Transport 被引量:1
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作者 Ying Ye Jiali Shen Rickard Bergqvist 《Journal of Transportation Technologies》 2014年第3期289-301,共13页
This paper develops a model for analyzing the potential of longer and heavier vehicles (LHVs) related to pre- and post-haulage in the intermodal rail-road transport chain (IRT). The paper considers the combined econom... This paper develops a model for analyzing the potential of longer and heavier vehicles (LHVs) related to pre- and post-haulage in the intermodal rail-road transport chain (IRT). The paper considers the combined economic and emission costs among three different transport networks including intermodal rail-road transport with current Swedish regulatory framework for trucks, intermodal rail-road transport with LHVs, and direct-road transport. The objective is to analyse the potential of high-capacity transport associated with pre- and post-haulage for enhancing the competitiveness of intermodal transport from a full-costs perspective. The model developed is applied to a Swedish context and case study. Research findings reveal that the break-even of the IRT compared to the direct road transport could be significantly lowered, which suggests the LHVs contribute to exploring the market of IRT over smaller flows. 展开更多
关键词 Intermodal Transport HCT Sustainable Transport pre-and Post-Haulage Modal Shift
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Long-term Efficacy of Pulmonary Artery Desnervation Treatment in Heart Failure With Preserved Ejection Fraction:A Subgroup Analysis of 3-year Results From the PADN-5 Study
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作者 Hang Zhang Wande Yu +5 位作者 Mengyu Zhang Wei Li Jing Kan Dujiang Xie Juan Zhang Shaoliang Chen 《Cardiology Discovery》 2024年第3期206-212,共7页
Objective:The Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure(PADN-5)study proved that pulmonary artery denervation(PADN)is associated with significant imp... Objective:The Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure(PADN-5)study proved that pulmonary artery denervation(PADN)is associated with significant improvements in hemodynamic and clinical outcomes in patients with combined pre-and post-capillary pulmonary hypertension(CpcPH).This study aimed to assess the 3-year clinical results of PADN in patients who had heart failure with preserved ejection fraction(HFpEF)developing into CpcPH(HFpEF-CpcPH).Methods:In this post hoc analysis of the PADN-5 trial,38 patients with HFpEF were included in screening out of 98 patients with CpcPH who were randomly assigned to treatment with sildenafil and sham PADN(sham PADN(plus sildenafil)group,abbreviated as sham group)or PADN(PADN group).HFpEF in the PADN-5 trial was defined as a left ventricular ejection fraction≥50%,and CpcPH was defined as a mean pulmonary arterial pressure≥25 mmHg,a pulmonary arterial wedge pressure>15 mmHg,and a pulmonary vascular resistance>3.0 WU.The changes in the 6-minute walk distance(6-MWD)and the plasma concentration of N-terminal pro-brain natriuretic peptide(NT-proBNP)at 6-month and 3-year follow-up,as well as the clinical endpoint of the occurrence of clinical worsening,defined as cardiopulmonary-related death,rehospitalization,or heart or lung transplantation at 3-year follow-up were examined.Results:Thirty-eight patients with HFpEF-CpcPH were assigned to the PADN group(n=19)or the sham group(n=19).At the 6-month follow-up,6-MWD(433(275,580)m vs.342(161,552)m),and reductions in NT-proBNP(−47%(−99%,331%)vs.−12%(−82%,54%))were significantly improved in the PADN group(all P<0.05).Over the 3-year follow-up period,PADN treatment resulted in marked increases in 6-MWD(450(186,510)m vs.348(135,435)m)and reductions in NT-proBNP(−55%(−99%,38%)vs.−10%(−80%,95%))(all P<0.05).Clinical worsening was experienced by 12 patients(63%)in the sham group,but by only 5 patients(26%)in the PADN group(hazard ratio=0.149,95%confidence interval:0.038–0.584,P=0.006).The 6-MWD and PADN treatments were independent predictors of clinical deterioration in patients with HFpEF-CpcPH.Conclusions:PADN therapy is associated with improvements in exercise capacity and clinical outcomes.PADN therapy may have a potential role in patients with HFpEF-CpcPH for whom current treatment options are limited. 展开更多
关键词 Heart failure Combined pre-and post-capillary pulmonary hypertension Pulmonary artery denervation 6-minute walk distance Clinical worsening
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Parental awareness on myopia prevention and control among 350 children
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作者 Tian-Tian Li Zi-Shui Fang +5 位作者 Yu-Xin Xue Shi-Jun Chen Ying-Xin Yang Tie-Jun Li Yue Yang Yan Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2109-2119,共11页
AIM:To understand the current situation of parental perspectives,knowledge,and practices concerning myopia prevention and control for both pre-and school-aged children.METHODS:This study was a cross-sectional survey t... AIM:To understand the current situation of parental perspectives,knowledge,and practices concerning myopia prevention and control for both pre-and school-aged children.METHODS:This study was a cross-sectional survey that involved children aged 0 to 15y and their parents.Participants were required to respond to an online questionnaire by scanning a quick response(QR)code.The questionnaire consisted of 25 tick-box questions and was open to response from December 22,2022,to January 5,2023.The dioptric traits of the children,the visual status and educational background of the parents,the parental perspectives towards myopia and its risks,and the parents’knowledge and practices related to myopia prevention and control were recorded and measured.The Chi-square test and binomial logistic regression were used for statistics.RESULTS:Totally 350 parents responded to the questionnaire.The prevalence and severity of myopia among the surveyed children exhibited a positive correlation with advancing age(P<0.001 and P=0.004,respectively).Nearly half of parents with myopic children considered myopia did not pose any health threat and could be effectively corrected(P<0.001).Parents who held master’s or doctoral degree demonstrated a better understanding of children’s vision standards for each age group(P=0.001),and 31.63% of them could undergo initial vision screening for their children during the age of 0 to 3y while parents with bachelor’s degree(34.04%)and below(32.43%)mainly initiated the vision examination for their children at the age of 4 to 6y(P=0.05).Parents with master’s or doctoral degree also exhibited more rational practices concerning outdoor time(P=0.048)and sleep time(P=0.044).No other significant discrepancy among the different educational groups in additional conceptions of myopia,such as hyperopia reserve,axis length,and corneal curvature alterations.Most parents preferred to employ conventional interventions,such as enhancing indoor lighting condition(80.00%)and ensuring appropriate reading posture and distance(71.71%).CONCLUSION:The current status of parental knowledge and practices about myopia prevention and control remains outdated and deficient.The administrative department should implement efficacious and adaptable measures to enhance parental awareness and foster their commitment towards myopia prevention and control. 展开更多
关键词 myopia myopia prevention and control parental perspectives pre-and school-aged children
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