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Enhanced recovery after surgery pathway: The use of fascia iliaca blocks causes delayed ambulation after total hip arthroplasty 被引量:1
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作者 Jamie-Lee Metesky junping chen Meg Rosenblatt 《World Journal of Anesthesiology》 2019年第2期13-18,共6页
BACKGROUND Fascia iliaca compartment blocks(FIBs) have been used to provide postoperative analgesia after total hip arthroplasty(THA). However, evidence of their efficacy remains limited. While pain control appears to... BACKGROUND Fascia iliaca compartment blocks(FIBs) have been used to provide postoperative analgesia after total hip arthroplasty(THA). However, evidence of their efficacy remains limited. While pain control appears to be satisfactory, quadriceps weakness may be an untoward consequence of the block. Prior studies have shown femoral nerve blocks and fascia iliaca blocks as being superior for pain control and ambulation following THA when compared to standard therapy of parenteral pain control. However, most studies allowed patients to ambulate on post-operative day(POD) 2-3, whereas new guidelines suggest ambulation on POD 0 is beneficial.AIM To determine the effect of FIB after THA in patients participating in an enhanced recovery after surgery(ERAS) program.METHODS We conducted a retrospective analysis of patients undergoing THA with or without FICBs and their ability to ambulate on POD 0 in accordance with ERAS protocol. Perioperative data was collected on 39 patients who underwent THA.Demographic data, anesthesia data, and ambulatory outcomes were compared.RESULTS Twenty patients had FIBs placed at the conclusion of the procedure, while 19 did not receive a block. Of the 20 patients with FIB, only 1 patient was able to ambulate. Of the 19 patients without FIB blocks, 17 were able to ambulate. All patients worked with physical therapy 2 h after arriving in the post-anesthesia care unit on POD 0.CONCLUSION Our data suggests an association between FIB and delayed ambulation in the immediate post-operative period. 展开更多
关键词 FASCIA iliaca Total hip ARTHROPLASTY Enhanced recovery AFTER surgery protocol Deep vein THROMBUS POST-OPERATIVE
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Singular spectrum analysis for the time-variable seasonal signals from GPS in Yunnan Province
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作者 Weijie Tan junping chen +2 位作者 Yize Zhang Bin Wang Songyun Wang 《Geodesy and Geodynamics》 EI CSCD 2024年第6期582-591,共10页
Studying the seasonal deformation in GPS time series is important to interpreting geophysical contributors and identifying unmodeled and mismodeled seasonal signals.Traditional seasonal signal extraction used the leas... Studying the seasonal deformation in GPS time series is important to interpreting geophysical contributors and identifying unmodeled and mismodeled seasonal signals.Traditional seasonal signal extraction used the least squares method,which models seasonal deformation as a constant seasonal amplitude and phase.However,the seasonal variations are not constant from year to year,and the seasonal amplitude and phase are time-variable.In order to obtain the time-variable seasonal signal in the GPS station coordinate time series,singular spectrum analysis(SSA)is conducted in this study.We firstly applied the SSA on simulated seasonal signals with different frequencies 1.00 cycle per year(cpy),1.04 cpy and with time-variable amplitude are superimposed.It was found that SSA can successfully obtain the seasonal variations with different frequencies and with time-variable amplitude superimposed.Then,SSA is carried out on the GPS observations in Yunnan Province.The results show that the time-variable amplitude seasonal signals are ubiquitous in Yunnan Province,and the timevariable amplitude change in 2019 in the region is extracted,which is further explained by the soil moisture mass loading and atmospheric pressure loading.After removing the two loading effects,the SSA obtained modulated seasonal signals which contain the obvious seasonal variations at frequency of 1.046 cpy,it is close with the GPS draconitic year,1.040 cpy.Hence,the time-variable amplitude changes in 2019 and the seasonal GPS draconitic year in the region could be discriminated successfully by SSA in Yunnan Province. 展开更多
关键词 Singular spectrum analysis Modulated seasonal signals Time-variable amplitude GPS draconitic year
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Contribution of the BDS to availability and reliability improvement:A case study of dam surface displacement monitoring in China
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作者 Shanqi Huang junping chen Hu Wang 《Geodesy and Geodynamics》 2019年第3期256-264,共9页
The GPS-only system is limited in dam surface monitoring because of its low availability and reliability due to the visible satellites are not enough. This dilemma is expected to be solved through incorporating the Ch... The GPS-only system is limited in dam surface monitoring because of its low availability and reliability due to the visible satellites are not enough. This dilemma is expected to be solved through incorporating the China’s BeiDou System(BDS). This contribution will quantitatively analyse the availability and reliability improvements from DBS in different shielding situations of dams. The analysis is conducted through simulating a dam obstruction with different size, azimuth and distance to receiver. The similar experiments are simulated in the area across China in order to explore these contributions in different locations. Quantitative analysis results derive conclusions:(1) In most areas, the availability improved from 50% of GPS-only to 95% of BDS + GPS when most of the GEO/IGSO satellites are not blocked, and to70% even when most of GEO/IGSO satellites are blocked.(2) The average MDBs can be reduced by half when most of the GEO/IGSO satellites are not blocked, and by 10% even when most of GEO/IGSO satellites are blocked. 展开更多
关键词 DAM surface MONITORING BDS AVAILABILITY RELIABILITY
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Genetic Diversity in the Environmental Conditioning of Two Sorghum (<i>Sorghum bicolor</i>L.) Hybrids
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作者 John J. Burke Yves Emendack +1 位作者 Chad Hayes junping chen 《American Journal of Plant Sciences》 2018年第4期817-831,共15页
Sorghum metabolism continually adapts to environmental temperature as thermal patterns modulate diurnally and seasonally. The degree of adaptation to any given temperature may be difficult to determine from phenotypic... Sorghum metabolism continually adapts to environmental temperature as thermal patterns modulate diurnally and seasonally. The degree of adaptation to any given temperature may be difficult to determine from phenotypic responses of the plants. The present study was designed to see if the efficiency of quantum yield of photosystem II could be used as a measure of how well leaf tissue metabolism was able to withstand a prolonged respiratory demand caused by elevated temperatures. The efficiency of quantum yield values of Pioneer 84G62 and Northrup King KS585 commercial sorghum hybrids showed that when the hybrids were grown in a 28&deg;C/20&deg;C day/night cycle in the greenhouse or the field, Pioneer hybrid 84G62 withstood subsequent elevated thermal challenges better than Northrup King KS585. The same hybrids grown in a 39&deg;C/32&deg;C day/night cycle showed similar efficiency of quantum yield values when thermally challenged. Water-deficit stress increased the heat resistance of the tissue raising the efficiency of quantum yield of both lines to the same level. Upon recovery from the water deficit stress the differential efficiency of quantum yield values between the two lines re-appeared. The data provided in this study suggest a metabolic advantage of Pioneer 84G62 to environmental thermal challenges compared with the Northrup King KS585. 展开更多
关键词 SORGHUM SORGHUM BICOLOR L. Thermal Sensitivity Adaptation
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Models and performance of SBAS and PPP of BDS 被引量:6
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作者 junping chen Yize Zhang +3 位作者 Chao Yu Ahao Wang Ziyuan Song Jianhua Zhou 《Satellite Navigation》 2022年第1期60-73,I0003,共15页
Satellite Based Augmentation System(SBAS)is one of the services provided by the BeiDou Navigation Satellite System(BDS).It broadcasts four types of diferential corrections to improve user application performance.These... Satellite Based Augmentation System(SBAS)is one of the services provided by the BeiDou Navigation Satellite System(BDS).It broadcasts four types of diferential corrections to improve user application performance.These corrections include the State Space Representation(SSR)based satellite orbit/clock corrections and ionospheric grid corrections,and the Observation Space Representation(OSR)based partition comprehensive corrections.The algorithms generating these SBAS corrections are not introduced in previous researches,and the user SBAS positioning performance with the contribution of BDS-3 has not been evaluated.In this paper,we present the BDS SBAS algorithms for these diferential corrections in detail.Four types of Precise Point Positioning(PPP)function models for BDS Dual-Frequency(DF)and Single-Frequency(SF)users using the OSR and SSR parameters are also proposed.One week of data in 2020 is collected at 20 reference stations including the observations of both BeiDou-2 Navigation Satellite System(BDS-2)and BeiDou-3 Navigation Satellite System(BDS-3)satellites,and the PPP under various scenarios are performed using all the datasets and the BDS SBAS broadcast corrections.The results show that the performance of BDS-2/BDS-3 combination is superior to that of BDS-2 only constellation.The positioning errors in Root Mean Square(RMS)for the static DF PPP are better than 8 cm/15 cm in horizontal/vertical directions,while for the static SF PPP are 11 cm/24 cm.In the scenarios of simulated kinematic PPP,three Dimension(3D)positioning errors can reach 0.5 m in less than 10 min for the DF PPP and 30 min for the SF PPP,and the RMSs of the DF and SF PPP are better than 17 cm/21 cm and 20 cm/32 cm in horizontal/vertical directions.In a real-time single-and dual-frequency kinematic positioning test,the positioning errors of all three components can reach 0.5 m within 30 min,and the positioning accuracy after solution convergence in the N,E and U directions is better than 0.3 m. 展开更多
关键词 SBAS BDS State Space Representation(SSR) Observation Space Representation(OSR) Precise point positioning
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Improving BDS broadcast ephemeris accuracy using ground-satellite-link observations 被引量:1
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作者 junping chen Jungang Wang +2 位作者 Chao Yu Yize Zhang Bin Wang 《Satellite Navigation》 2022年第1期85-96,I0004,共13页
The BeiDou Navigation Satellite System(BDS)employs a hybrid constellation including GEO(Geosynchronous Earth Orbit),IGSO(Inclined Geosynchronous Orbit),and MEO(Medium Earth Orbit)satellites,where the GEO and IGSO sate... The BeiDou Navigation Satellite System(BDS)employs a hybrid constellation including GEO(Geosynchronous Earth Orbit),IGSO(Inclined Geosynchronous Orbit),and MEO(Medium Earth Orbit)satellites,where the GEO and IGSO satellites are critical to providing continuous and reliable Positioning,Navigation,and Timing(PNT)services in the Asia–Pacifc region.To handle the inconsistency between the satellite orbits and clocks in the broadcast ephemeris,which are determined by the Orbit Determination and Time Synchronization(ODTS)and the Two-way Satellite Time Frequency Transfer(TWSTFT)technique,respectively,we present the strategies using ground-satellite-link observations to improve the accuracy of broadcast ephemeris.The clock diferences between the ODTS and TWSTFT techniques are used for correcting the radial orbit component to derive the refned orbits,which are used to generate the refned broadcast ephemeris.The test results show the precision of the refned orbits is improved by 50–60%in the 3-h to 12-h predicted arcs for the GEO satellites,and by 40–50%for the IGSO satellites.Moreover,the validation using satellite laser ranging observations shows the mean precision of the refned broadcast ephemeris is improved by 27%compared to the original one.Applying the proposed strategies in the BDS Operational Control Segment(OCS),the time evolution of BDS Single Point Positioning(SPP)in the period from Jan.2016 to April 2021 is evaluated.The SPP accuracy is improved from 1.94,2.06 and 3.29 m to 1.39,1.85,and 2.39 m in the north,east,and up components,respectively.Further update with the inclusion of BDS-3 satellites improve the corresponding SPP precision to 0.68,0.70 and 1.91 m. 展开更多
关键词 BDS Broadcast ephemeris TWSTFT Orbit determination
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