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基于REOF的不同量级降雨侵蚀力时空变化——以重庆市为例
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作者 靳军英 王林 +1 位作者 金铁生 张卫华 《西南大学学报(自然科学版)》 CAS 北大核心 2025年第1期163-177,共15页
研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,RE... 研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,REOF)对降雨侵蚀力进行地理分区,并结合R/S、5年滑动平均、Mann-Kendall检验等方法,分析各分区不同量级降雨侵蚀力时空变化。结果表明:①重庆市降雨侵蚀力可分为6个地理区域(Ⅰ-Ⅵ区);②重庆市多年平均降雨侵蚀力为5784.04 MJ·mm/(hm^(2)·h·a),不同降雨侵蚀力从大到小依次为:大雨、暴雨、中雨、大暴雨;③大雨侵蚀力在Ⅰ-Ⅲ区和Ⅴ-Ⅵ区占主导优势,暴雨侵蚀力在Ⅳ区占主导优势。各分区中,中雨、大雨及暴雨侵蚀力主要集中在5-9月,大暴雨侵蚀力集中在6-8月;④各区不同量级降雨侵蚀力年际变化从小到大依次为:中雨、大雨、暴雨、大暴雨;同一量级降雨侵蚀力的整体变化趋势均不显著;Hurst指数表明,中雨侵蚀力在Ⅰ和Ⅴ区、大雨侵蚀力在Ⅱ和Ⅴ区、大暴雨侵蚀力在Ⅰ和Ⅲ区呈强持续上升趋势;⑤中雨、大雨及大暴雨侵蚀力在渝东南、渝东北占主导优势,暴雨侵蚀力在渝西以及重庆中部占主导优势,且Ⅰ区酉阳和秀山、Ⅱ区开州、Ⅲ区北碚和铜梁、Ⅳ区璧山和永川、Ⅴ区巫溪和云阳及Ⅵ区忠县是不同量级降雨侵蚀力的高峰中心。通过对重庆各分区不同量级降雨侵蚀力的分析,明确了可能引起土壤侵蚀的主要雨型、高发时期和潜在风险较高的地区,可为区域水土流失动态监测和水土保持措施的合理制定提供参考。 展开更多
关键词 降雨侵蚀力 时空变化 旋转经验正交分解法 MK非参数趋势检验 r/S分析法
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The calculation of the Reproducibility Error in the technological system with the clamp on the gas power
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作者 沈兴东 郑士成 《自动化博览》 2011年第S2期169-172,共4页
The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and ... The paper deduced a calculation formula by the classic control theory on the Reproducibility Error of parts processing in the technology system,the flexible clamp system, with the clamping device on the gas power,and analyzed its influencing factor with examples,the Reproducibility Error law:\ The larger the diameter of the cylinder,the smaller the error; the slower the tool speed,(k values smaller),the smaller the error. 展开更多
关键词 CYLINDEr CLAMPING reproducibility ErrOr TrANSFEr function ovality
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Reproducibility of optical quality parameters measured at objective and subjective best focuses in a doublepass system 被引量:8
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作者 Ai-Lian Hu Li-Ya Qiao +3 位作者 Ye Zhang Xiao-Gu Cai Lei Li Xiu-Hua Wan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第5期1043-1050,共8页
AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.METHODSThirty Chinese healthy adults (19 to 40 yea... AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.METHODSThirty Chinese healthy adults (19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System (OQAS) with an artificial pupil diameter of 4.0 mm.RESULTSWith each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency (MTF<sub>cutoff</sub>), the Strehl<sup>2D</sup> ratio, the OQAS values (OVs) at contrasts of 100%, 20%, 9% and the objective scatter index (OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit (RL) and the coefficient of repeatability (COR). Reproducibility of the two methods was evaluated by intra-class correlation coefficient (ICC) and the 95% limits of agreement (Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs (percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13% and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83% and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters (in comparison of the two methods) ranged from -0.57 to 42.18 (MTF<sub>cutoff</sub>), -0.01 to 0.23 (Strehl<sup>2D</sup> ratio), -0.02 to 1.40 (OV<sub>100%</sub>), -0.10 to 1.75 (OV<sub>20%</sub>), -0.14 to 1.80 (OV<sub>9%</sub>) and -1.46 to 0.18 (OSI).CONCLUSIONMeasurements provided by OQAS with either method showed a good repeatability. However, the results obtained from the two different measurement methods showed a poor reproducibility. These findings suggest that it might be best to evaluate patients' optical quality by OQAS using the best focus as chosen automatically by the instrument. 展开更多
关键词 optical quality double-pass system best focus rEPEATABILITY reproducibility
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Quantitative diffusion-weighted magnetic resonance enterography in ileal Crohn’s disease: A systematic analysis of intra and interobserver reproducibility 被引量:8
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作者 Hao Yu Ya-Qi Shen +4 位作者 Fang-Qin Tan Zi-Ling Zhou Zhen Li Dao-Yu Hu John N Morelli 《World Journal of Gastroenterology》 SCIE CAS 2019年第27期3619-3633,共15页
BACKGROUND Magnetic resonance enterography(MRE) is increasingly attractive as a noninvasive and radiation-free tool for assessing Crohn’s disease(CD). Diffusionweighted imaging(DWI) is recommended as an optional MRE ... BACKGROUND Magnetic resonance enterography(MRE) is increasingly attractive as a noninvasive and radiation-free tool for assessing Crohn’s disease(CD). Diffusionweighted imaging(DWI) is recommended as an optional MRE sequence for CD by the European Society of Gastrointestinal and Abdominal Radiology, and has shown a superb potential as a quantitative modality for bowel inflammation evaluation. However, the measurement reproducibility of quantitative DWI analysis in MRE has not been ascertained so far. To facilitate the application of quantitative diffusion-weighted MRE in the clinical routine, systematic investigations of the intra and interobserver reproducibility of DWI quantitative parameters should be performed.AIM To evaluate the intra and interobserver reproducibility of quantitative analysis for diffusion-weighted MRE(DW-MRE) in ileal CD.METHODS Forty-four subjects(21 with CD and 23 control subjects) who underwent ileocolonoscopy and DW-MRE(b = 800 s/mm2) within one week were included.Two radiologists independently measured apparent diffusion coefficients(ADC)of the terminal ileum and signal intensity ratio(SR) of the terminal ileum to ipsilateral psoas muscle on DWI images(b = 800 s/mm2). Between-and withinreader agreements were assessed using intraclass correlation coefficients(ICC),coefficients of variation(CoV), and 95% limits of agreement of Bland-Altman plots(BA-LA LoA). Diagnostic performances of ADC and SR for identifying inflamed terminal ileum from the normal were evaluated by receiver operating characteristic(ROC) curve analysis.RESULTS There were no significant differences in ADC or SR values between the two sessions or between the two radiologists either in the CD or control group(paired t-test, P > 0.05). The intra and interobserver reproducibility of ADC(ICC: 0.952-0.984;CoV: 3.73-6.28%;BA-LA LoA: ±11.27% to ±15.88%) and SR(ICC: 0.969-0.989;CoV: 3.51%-4.64%;BA-LA LoA: ±10.62% to ±15.45%) was excellent for CD.Agreement of ADC measurements was slightly less in control subjects(ICC:0.641-0.736;CoV: 10.47%-11.43%;BA-LA LoA: ± 26.59% to ± 30.83%). SR of normal terminal ileum demonstrated high intra and interobserver reproducibility(ICC: 0.944-0.974;CoV: 3.73%-6.28%;BA-LA LoA: ± 18.58% to ± 24.43%). ADC and SR of two readers had outstanding diagnostic efficiencies(area under the ROC curve: 0.923-0.988).CONCLUSION Quantitative parameters derived from DW-MRE have good to excellent intra and interobserver agreements with high diagnostic accuracy, and can serve as robust and efficient quantitative biomarkers for CD evaluation. 展开更多
关键词 Magnetic resonance IMAGING DIFFUSION-WEIGHTED IMAGING Crohn’s disease ILEUM reproducibility
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Evaluation of Glycosaminoglycan in the Lumbar Disc Using Chemical Exchange Saturation Transfer MR at 3.0 Tesla:Reproducibility and Correlation with Disc Degeneration 被引量:8
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作者 Deng Min Yuan Jing +3 位作者 Chen Wei Tian Queenie Chan James F Griffith Wang Yi Xiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第1期47-55,共9页
Objective This study aims to explore the clinical applicability and relevance of giycosaminoglycan Chemical Exchange Saturation Transfer (gagCEST) for intervertebral disc. Methods 25 subjects ranging in age from 24 ... Objective This study aims to explore the clinical applicability and relevance of giycosaminoglycan Chemical Exchange Saturation Transfer (gagCEST) for intervertebral disc. Methods 25 subjects ranging in age from 24 yrs to 74 yrs were enrolled, gagCEST was acquired using a single-slice TSE sequence on a 3T. Saturation used a continuous rectangular RF pulse with B1=0.8 I^T and a fixed duration time =1100 ms. Sagittal image was obtained firstly without saturation pulse, and then saturated images were acquired at 52 offsets ranging from +0.i25 to +_7 parts per million (ppm). MR T2 relaxivity map was acquired at the identical location. Six subjects were scanned twice to assess scan-rescan reproducibility. Results GagCEST intraclass correlation coefficient (ICC) of six subjects was 0.759 for nucleus pulposus (NP) and 0.508 for annulus fibrosus (AF). Bland-Altman plots showed NP had a mean difference of 0.10% (95% limits of agreement: -3.02% to 3.22%); while that of AF was 0.34% (95% limits of agreement: -2.28% to 2.95%). For the 25 subjects, gag CEST in NP decreased as disc degeneration increased, with a similar trend to T2 relaxivity. Gag CEST of AF showed a better correlation with disc degeneration than T2 relaxivity. Conclusion GagCEST in NP and AF decreased as disc degeneration increased, while gagCEST in AF showed a better correlation than T2 relaxivity. 展开更多
关键词 GLYCOSAMINOGLYCAN Chemical Exchange Saturation Transfer (CEST) reproducibility Discdegeneration
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Repeatability and Reproducibility of Quantitative Assessment of the Retinal Microvasculature Using Optical Coherence Tomography Angiography Based on Optical Microangiography 被引量:9
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作者 ZHAO Qi YANG Wen Li +12 位作者 WANG Xiao Na Ruikang K Wang YOU Qi Sheng CHU Zhong Di XIN Chen ZHANG Meng Yu LI Dong Jun WANG Zi Yang CHEN Wei LI Yi Feng CUI Rui SHEN Lin WEI Wen Bin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第6期407-412,共6页
Objective The aim of this study was to determine the repeatability and reproducibility of optical coherence tomography angiography(OCTA) based on optical microangiography(OMAG) measurements of macular vessels in n... Objective The aim of this study was to determine the repeatability and reproducibility of optical coherence tomography angiography(OCTA) based on optical microangiography(OMAG) measurements of macular vessels in normal eyes. Methods In this prospective cohort study, 40 eyes of 40 healthy volunteers underwent repeated OCTA(Cirrus HD-OCT 5000 angiography system, Carl Zeiss Meditec, Inc.) scans on two separate visit days. On each visit day, the eyes were scanned three times. The following parameters were used to quantitatively describe the OCTA images of the superficial vascular network: vessel area density(VAD), vessel skeleton density(VSD), vessel diameter index(VDI), vessel perimeter index(VPI), vessel complexity index(VCI), flux, and foveal avascular zone(FAZ). Coefficient of variation(CV) and intraclass correlation coefficient(ICC) were calculated for evaluating intravisit and intervisit repeatability, as well as interobserver reproducibility. Results The measurements showed high repeatability [CVs ≤ 4.2%(intravisit) and ≤ 4.6%(intervisit)] and interobserver reproducibility(ICCs ≥ 0.923) for all parameters. Conclusion This study demonstrated good repeatability and reproducibility of OCTA based on OMAG for the measurement of superficial vessel parameters in normal eyes. 展开更多
关键词 Optical coherence tomography angiography rEPEATABILITY reproducibility Macular bloodflow retinal superficial capillary Vascular quantification
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Reproducibility of peripapillary retinal nerve fiber layer thickness measurements with Cirrus HD-OCT in glaucomatous eyes 被引量:2
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作者 Reza Soltani-Moghadam Yousef Alizadeh +1 位作者 Ehsan Kazemnezhad Leili Mohamadreza Absari Haghighi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第1期113-117,共5页
AIM: To assess the reproducibility of Cirrus high-definition optical coherence tomography(HD-OCT; Carl Zeiss Meditec, Dublin, CA, USA) for analysis of peripapillary retinal nerve fiber layer(RNFL) thickness in glaucom... AIM: To assess the reproducibility of Cirrus high-definition optical coherence tomography(HD-OCT; Carl Zeiss Meditec, Dublin, CA, USA) for analysis of peripapillary retinal nerve fiber layer(RNFL) thickness in glaucomatous eyesMETHODS: Forty-five eyes(one eye from each glaucomatous patient) were imaged with Cirrus HD-OCT.Each eye was imaged three times by two separate operators. Intraclass correlation coefficient(ICC),coefficient of variation(CV), and test-retest variability were evaluated for both intraobserver and interobsever measurementsRESULTS: In intraobserver measurements, the average RNFL thickness ICC was 0.983. CV and test-retest variability were 2.3% and 4.4 μm respectively. In quadrants ICC ranged from 0.886 to 0.956, the lowest associated with nasal quadrant and CV ranged from 3.6%to 7.7%. In interobsever measurements, the average RNFL thickness ICC was 0.979. CV and test-retest variability were 2.4% and 4.5 μm respectively. In quadrants ICC ranged from 0.886 to 0.957, the lowest associated with nasal quadrant and CV ranged from 3.8%to 8.6%.CONCLUSION: The reproducibility of Cirrus OCT for RNFL thickness is sufficiently good to be useful clinically as a measure of glaucoma progression. 展开更多
关键词 opticalcoherencetomography reproducibility GLAUCOMA retinal nerve fiber layer
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Reproducibility and Validity of a Chinese Food Frequency Questionnaire 被引量:18
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作者 Water WILLETT Kyoko HASEGAWA 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第S1期1-38,共38页
Objectives This study was design to develop a semi-quantitative Chinese Food Frequency Questionnaire (FFQ) and to conduct a validation study for the questionnaire. Methods Based on the survey experience in recent ye... Objectives This study was design to develop a semi-quantitative Chinese Food Frequency Questionnaire (FFQ) and to conduct a validation study for the questionnaire. Methods Based on the survey experience in recent years, a new Chinese food frequency questionnaire (FFQ) with 149 items in 17 food categories was developed. A validation study on this new FFQ was conducted in Jiangsu and Beijing of China between 1999 and 2001. The period of study covered 1 year and the FFQ was validated by comparing with data obtained by a six repeated 24-hour recalls for 3 consecutive days, or a totally 18-day 24- hour recall throughout the year. A total of 271 healthy adult subjects were enrolled in the study. Food and nutrient intakes measured by the 18-day dietary recalls and food frequency questionnaires (FFQs) were computed in the National Institute for Nutrition and Food Safety, China CDC using the existing nutrition database. The average daily intake of foods and nutrients over the 18-day recall was used to compare with FFQ1 and FFQ2, which was conducted at the beginning and the end of the year, respectively. All statistical analyses were carried out using SAS software version 6.12. 展开更多
关键词 FFQ reproducibility and Validity of a Chinese Food Frequency Questionnaire
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Diffusion-weighted magnetic resonance imaging in cancer: Reported apparent diffusion coefficients,in-vitro and invivo reproducibility 被引量:2
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作者 Maysam M Jafar Arman Parsai Marc E Miquel 《World Journal of Radiology》 CAS 2016年第1期21-49,共29页
There is considerable disparity in the published apparent diffusion coefficient(ADC) values across different anatomies. Institutions are increasingly assessing repeatability and reproducibility of the derived ADC to d... There is considerable disparity in the published apparent diffusion coefficient(ADC) values across different anatomies. Institutions are increasingly assessing repeatability and reproducibility of the derived ADC to determine its variation,which could potentially be used as an indicator in determining tumour aggressiveness or assessing tumour response. In this manuscript,a review of selected articles published to date in healthy extracranial body diffusion-weighted magnetic resonance imaging is presented,detailing reported ADC values and discussing their variation across different studies. In total 115 studies were selected including 28 for liver parenchyma,15 for kidney(renal parenchyma),14 for spleen,13 for pancreatic body,6 for gallbladder,13 for prostate,13 for uterus(endometrium,myometrium,cervix) and 13 for fibroglandular breast tissue. Median ADC values in selected studies were found to be 1.28 × 10-3 mm2/s in liver,1.94 × 10-3 mm2/s in kidney,1.60 × 10-3 mm2/s in pancreatic body,0.85 × 10-3 mm2/s in spleen,2.73 × 10-3 mm2/s in gallbladder,1.64 × 10-3 mm2/s and 1.31 × 10-3 mm2/s in prostate peripheral zone and central gland respectively(combined median value of 1.54×10-3 mm2/s),1.44 × 10-3 mm2/s in endometrium,1.53 × 10-3 mm2/s in myometrium,1.71 × 10-3 mm2/s in cervix and 1.92 × 10-3 mm2/s in breast. In addition,six phantom studies and thirteen in vivo studies were summarized to compare repeatability and reproducibility of the measured ADC. All selected phantom studies demonstrated lower intra-scanner and inter-scanner variation compared to in vivo studies. Based on the findings of this manuscript,it is recommended that protocols need to be optimised for the body part studied and that system-induced variability must be established using a standardized phantom in any clinical study. Reproducibility of the measured ADC must also be assessed in a volunteer population,as variations are far more significant in vivo compared with phantom studies. 展开更多
关键词 Diffusion-weighted magnetic resonance IMAGING APPArENT DIFFUSION COEFFICIENT reproducibility APPArENT DIFFUSION COEFFICIENT CANCEr IMAGING Extracranial organs
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The role of the gut microbiota on animal model reproducibility 被引量:4
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作者 Patricia V.Turner 《Animal Models and Experimental Medicine》 2018年第2期109-115,共7页
The gut microbiota is composed of approximately 10^(10)-10^(14) cells, including fungi,bacteria, archaea, protozoa, viruses, and bacteriophages; their genes and their various metabolites were found throughout the gast... The gut microbiota is composed of approximately 10^(10)-10^(14) cells, including fungi,bacteria, archaea, protozoa, viruses, and bacteriophages; their genes and their various metabolites were found throughout the gastrointestinal tract. It has co-evolved with each species to assist with day to day bodily functions, such as digestion,metabolism of xenobiotics, development of mucosal immunity and immunomodulation, and protection against invading pathogens. Because of the significant beneficial impact that gut microbiota may have, there is interest in learning more about it and translating these findings into clinical therapies. Results from recent studies characterizing the gut microbiota of various species have demonstrated the range of influences that may affect gut microbiota diversity, including animal strain, obesity, types of enrichment used, bedding and housing methods, treatment with antimicrobials,vendor source, specific animal housing, diet, and intercurrent disease. Relatively little is known about the functional consequences of alterations of the gut microbiota and exactly how changes in richness and diversity of the microbiota translate into changes in health and susceptibility to disease. Furthermore, questions have been raised as to whether germ-free or even ultraclean, barrier-raised mice are relevant models of human disease, given their significantly reduced gut microbiota diversity and complexity compared with conventionally housed mice. In addition, evidence suggests that the specific anatomical location selected for assessing the gut microbiota has a highly significant effect on study outcomes, in that bacterial phyla change significantly along the gastrointestinal tract. This paper will explore animal model reproducibility in light of this information about the gut microbiota. 展开更多
关键词 ANIMAL models GASTrOINTESTINAL MICrOBIOTA MICE reproducibility
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Monitoring recovery by physical therapists using the FIM scale during rehabilitation programs: An inter-rater and intra-rater reproducibility study 被引量:1
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作者 Tommasina Russo Giorgio Felzani +2 位作者 Mario Giunta Cristina Di Mascio Carmine Marini 《Health》 2013年第6期99-104,共6页
Our aim was to evaluate the reproducibility of the Functional Independence Measure (FIM) scale when assessed by physical therapists in the routine setting of a Rehabilitation Hospital. We included a consecutive series... Our aim was to evaluate the reproducibility of the Functional Independence Measure (FIM) scale when assessed by physical therapists in the routine setting of a Rehabilitation Hospital. We included a consecutive series of patients with spinal cord or cerebral lesions. Each of the 50 selected patients was evaluated by two of the 5 experienced physical therapists participating in the study. The degree of inter-rater and intrarater agreement was measured by a weighted k statistic, k for perfect agreement, and k for the agreement with tolerance. The weighted k index for inter-rater agreement on the FIM score was in the almost perfect range (k 0.87;95% CI = 0.79 - 0.95), but a 20-point tolerance was necessary to reach a k value of 0.81 (95% CI = 0.66 - 0.95). Agreement was substantial or almost perfect for most subscales, but the k index with 1-point tolerance reached the almost perfect rating for comprehension only. For intra-rater agreement, weighted k index was in the almost perfect range for the FIM score and for all subscales;kappa index reached the almost perfect range with a 4-point tolerance for FIM score and with 1-point of tolerance for all subscales except interpersonal relations. FIM is useful to monitor patient improvement during rehabilitation treatment, mostly when assessed by the same physical therapist. 展开更多
关键词 reproducibility rEHABILITATION Functional INDEPENDENCE Measure
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Reproducibility of macular perfusion parameters in non-proliferative diabetic retinopathy patients by two different OCTA sweep modes 被引量:3
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作者 Shen Qu Ao Rong +4 位作者 Yun-Li Niu Xin Liu Yu-Shan Zhang Chun-Yu Liu Yan-Long Bi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第9期1483-1487,共5页
·AIM:To assess the reproducibility of macular perfusion parameters in non-proliferative diabetic retinopathy(NPDR)patients measured by different examiners and two different sweep modes of optical coherence tomogr... ·AIM:To assess the reproducibility of macular perfusion parameters in non-proliferative diabetic retinopathy(NPDR)patients measured by different examiners and two different sweep modes of optical coherence tomography angiography(OCTA).·METHODS:Ninety-eight(98 eyes)patients with NPDR were included in this study.All participates were performed three times using Cirrus OCTA with Angiography 3×3 mm^(2)and 6×6 mm^(2)sweep mode by two examiners.The macular foveal avascular zone(FAZ)and vessel density(VD)in the superficial retinal layer(SRL)were measured.The reproducibility of the measurements was evaluated with intraclass correlation coefficients(ICC)and coefficient of variation(CoV).·RESULTS:The intra-mode ICCs of Angiography 3×3 mm^(2)and 6×6 mm^(2)sweep mode were 0.957 to 0.959 and 0.964 to 0.977,respectively;and the inter-mode ICCs were 0.962 to 0.970.The intra-examiner ICCs of macular perfusion parameters were>0.950;and the inter-examiner ICCs were0.928 to 0.969.All CoVs were<1.0%.·CONCLUSION:Cirrus OCTA can measure macular perfusion parameters in NPDR patients with excellent reproducibility.The measurements of FAZ and VD in the SRL determined by Angiography 3×3 mm^(2)and 6×6 mm^(2)sweep mode are highly consistent and both sweep modes are suitable for macular perfusion parameters measurement. 展开更多
关键词 optical coherence tomography angiography macular per fusion parameters reproducibility non-proliferative diabetic retinopathy
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Short- and medium-term reproducibility of gastric emptying of a solid meal determined by a low dose of ^(13)C-octanoic acid and nondispersive isotope-selective infrared spectrometry 被引量:2
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作者 Anna Kasicka-Jonderko Magdalena Kami■ska +2 位作者 Krzysztof Jonderko Olga Setera Barbara Blo■ska-Fajfrowska 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第8期1243-1248,共6页
AIM: To evaluate the reproducibility of a modified 13^C breath test-based measurement of solid phase gastric emptying (GE) within the frames of a simple-repeated measure study protocol. METHODS: Twelve healthy sub... AIM: To evaluate the reproducibility of a modified 13^C breath test-based measurement of solid phase gastric emptying (GE) within the frames of a simple-repeated measure study protocol. METHODS: Twelve healthy subjects (6 females and 6 males, mean age 24.9+0.7 years) were recruited to undergo three identical GE examinations. In six subjects the first two examinations were performed 2 d apart, and the third session was carried out at a median interval of 19.5 d (range 18 - 20 d) from the second one. In another six subjects the first two measurements were taken 20 d apart (median, range: 17-23 d), whereas the third session took place 2 d after the second one. Probes of expiratory air collected before and during six hours after intake of a solid meal (378 kcal) labelled with 75 μL (68 mg) 13^C-octanoic acid, were measured for 13^CO2 enrichment with the nondispersive isotopeselective infrared spectrometry NDIRS apparatus. RESULTS: Taking coefficients of variation for paired examinations into account, the short-term reproducibility of the GE measurement was slightly but not significantly better than the medium-term one: 7.7% and 11.2% for the lag phase (T-Lag), 7.3% and 10.9% for the gastric half emptying time (T1/2). The least differences in GE parameters detectable at P= 0.05 level in the 12 paired examinations were 9.6 and 15.6 min for T-Lag, 11.6 and 19.7 min for T1/2 by a two-day or two to three-week time gap, respectively CONCLUSION: The low-cost modification of the breath test involving a lower dose of 13^C-octanoic acid and NDIRS, renders good short- and medium-term reproducibility, as well as sensitivity of the measurement of gastric emptying of solids. 展开更多
关键词 13^C breath test Gastric emptying Nondispersive isotope-selective infrared spectrometry 13^C-octanoic acid reproducibility
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^(13)C-methacetin breath test reproducibility study reveals persistent CYP1A2 stimulation on repeat examinations 被引量:1
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作者 Anna Kasicka-Jonderko Anna Nita +2 位作者 Krzysztof Jonderko Magdalena Kamińska Barbara Bońska-Fajfrowska 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第45期4979-4986,共8页
AIM: To find the most reproducible quantitative parameter of a standard 13C-methacetin breath test (13C-MBT). METHODS: Twenty healthy volunteers (10 female, 10 male) underwent the 13C-MBT after intake of 75 mg 13C-met... AIM: To find the most reproducible quantitative parameter of a standard 13C-methacetin breath test (13C-MBT). METHODS: Twenty healthy volunteers (10 female, 10 male) underwent the 13C-MBT after intake of 75 mg 13C-methacetin p.o. on three occasions. Short-and medium-term reproducibility was assessed with paired examinations taken at an interval of 2 and 18 d (medians), respectively. RESULTS: The reproducibility of the 1-h cumulative 13C recovery (AUC0-60), characterized by a coefficient of variation of 10%, appeared to be considerably better than the reproducibility of the maximum momentary 13C recovery or the time of reaching it. Remarkably, as opposed to the short gap between consecutive examinations, the capacity of the liver to handle 13C-methacetin increased slightly but statistically significantly when a repeat dose was administered after two to three weeks.Regarding the AUC0-60, the magnitude of this fixed bias amounted to 7.5%. Neither the time gap between the repeat examinations nor the gender of the subjects affected the 13C-MBT reproducibility. CONCLUSION: 13C-MBT is most reproducibly quantified by the cumulative 13C recovery, but the exactitude thereof may be modestly affected by persistent stimulation of CYP1A2 on repeat examinations. 展开更多
关键词 13C-Methacetin Breath test Isotope application in medicine Liver reproducibility
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AHermitian C^(2) Differential Reproducing Kernel Interpolation Meshless Method for the 3D Microstructure-Dependent Static Flexural Analysis of Simply Supported and Functionally Graded Microplates
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作者 Chih-Ping Wu Ruei-Syuan Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期917-949,共33页
This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredepend... This work develops a Hermitian C^(2) differential reproducing kernel interpolation meshless(DRKIM)method within the consistent couple stress theory(CCST)framework to study the three-dimensional(3D)microstructuredependent static flexural behavior of a functionally graded(FG)microplate subjected to mechanical loads and placed under full simple supports.In the formulation,we select the transverse stress and displacement components and their first-and second-order derivatives as primary variables.Then,we set up the differential reproducing conditions(DRCs)to obtain the shape functions of the Hermitian C^(2) differential reproducing kernel(DRK)interpolant’s derivatives without using direct differentiation.The interpolant’s shape function is combined with a primitive function that possesses Kronecker delta properties and an enrichment function that constituents DRCs.As a result,the primary variables and their first-and second-order derivatives satisfy the nodal interpolation properties.Subsequently,incorporating ourHermitianC^(2)DRKinterpolant intothe strong formof the3DCCST,we develop a DRKIM method to analyze the FG microplate’s 3D microstructure-dependent static flexural behavior.The Hermitian C^(2) DRKIM method is confirmed to be accurate and fast in its convergence rate by comparing the solutions it produces with the relevant 3D solutions available in the literature.Finally,the impact of essential factors on the transverse stresses,in-plane stresses,displacements,and couple stresses that are induced in the loaded microplate is examined.These factors include the length-to-thickness ratio,the material length-scale parameter,and the inhomogeneity index,which appear to be significant. 展开更多
关键词 Consistent/modified couple stress theory differential reproducing kernel methods microplates point collocation methods static flexural 3D microstructure-dependent analysis
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A Sputtering Deposition of Al Enhances the Output Reproducibility in a Conducting Rubber Force Sensor 被引量:1
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作者 Masato Ohmukai Yasushi Kami 《Journal of Sensor Technology》 2016年第3期46-55,共11页
Compressive force sensors or pressure sensors are indispensable to tactile sensors in humanoid robots. It is investigated that low-cost electro-conducting rubber sheets are applied to the force sensor, of which the bi... Compressive force sensors or pressure sensors are indispensable to tactile sensors in humanoid robots. It is investigated that low-cost electro-conducting rubber sheets are applied to the force sensor, of which the biggest problem is its poor reproducibility. It was found that the aluminum deposition by a vacuum evaporation method shows excellent characteristics but suffers deterioration by a radiation heating effect. The aluminum electrode was deposited by a sputtering method, known to have an advantage of a low-temperature method, and the reproducibility of the output was improved. 展开更多
关键词 Conducting rubber Force Sensor ELECTrODE Magnetron Sputtering reproducibility
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A novel method for geometric quality assurance of rock joint replicas in direct shear testing-Part 1:Derivation of quality assurance parameters and geometric reproducibility 被引量:1
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作者 J.Larsson F.Johansson +3 位作者 D.Mas Ivars E.Johnson M.Flansbjer N.W.Portal 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2193-2208,共16页
Since each rock joint is unique by nature,the utilization of replicas in direct shear testing is required to carry out experimental parameter studies.However,information about the ability of the replicas to simulate t... Since each rock joint is unique by nature,the utilization of replicas in direct shear testing is required to carry out experimental parameter studies.However,information about the ability of the replicas to simulate the shear mechanical behavior of the rock joint and their dispersion in direct shear testing is lacking.With the aim to facilitate generation of high-quality direct shear test data from replicas,a novel component in the testing procedure is introduced by presenting two parameters for geometric quality assurance.The parameters are derived from surface comparisons of three-dimensional(3D)scanning data of the rock joint and its replicas.The first parameter,smf,captures morphological deviations between the replica and the rock joint surfaces.smf is derived as the standard deviation of the deviations between the coordinate points of the replica and the rock joint.Four sources of errors introduced in the replica manufacturing process employed in this study could be identified.These errors could be minimized,yielding replicas with smf0.06 mm.The second parameter is a vector,VHp100,which describes deviations with respect to the shear direction.It is the projection of the 100 mm long normal vector of the best-fit plane of the replica joint surface to the corresponding plane of the rock joint.VHp100was found to be less than or equal to 0.36 mm in this study.Application of these two geometric quality assurance parameters demonstrates that it is possible to manufacture replicas with high geometric similarity to the rock joint.In a subsequent paper(part 2),smf and VHp100 are incorporated in a novel quality assurance method,in which the parameters shall be evaluated prior to direct shear testing.Replicas having parameter values below established thresholds shall have a known and narrow dispersion and imitate the shear mechanical behavior of the rock joint. 展开更多
关键词 Three-dimensional(3D)scanning Geometric reproducibility Geometric quality assurance replicas rock joint Surface comparisons
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Discussion on Repeatability and Reproducibility of Measuring Method in ISO 5725
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作者 朱家平 《China Standardization》 2013年第1期80-87,共8页
This paper discusses the repeatability and reproducibility of the international standard of ISO 5725:1994 Accuracy (trueness and precision) of Measurement Methods and Results, two concepts of "inter-laboratory var... This paper discusses the repeatability and reproducibility of the international standard of ISO 5725:1994 Accuracy (trueness and precision) of Measurement Methods and Results, two concepts of "inter-laboratory variance" and "reproducible variance" in the standard are questioned, the corresponding improvement idea is introduced, which aims to make this standard more rigorous, scientific and logical. 展开更多
关键词 ISO 5725 rEPEATABILITY reproducibility UNCErTAINTY inter-laboratory variance reproducible variance
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IP3R2及RYR2介导Ca^(2+)信号在急性一氧化碳中毒迟发性脑病小鼠模型中的表达
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作者 赵吉利 孟天予 +5 位作者 岳雅蓉 张鑫 杜文倩 张鑫宇 薛慧 项文平 《中国组织工程研究》 CAS 北大核心 2025年第2期254-261,共8页
背景:研究发现星形胶质细胞中Ca^(2+)的表达与认知功能密切相关,目前由1,4,5-三磷酸肌醇受体(Inositol 1,4,5-trisphosphate receptors,IP3Rs)2、兰尼碱受体(ryanodine receptors,RYRs)2受体及其调控的Ca^(2+)信号通路已经成为认知障碍... 背景:研究发现星形胶质细胞中Ca^(2+)的表达与认知功能密切相关,目前由1,4,5-三磷酸肌醇受体(Inositol 1,4,5-trisphosphate receptors,IP3Rs)2、兰尼碱受体(ryanodine receptors,RYRs)2受体及其调控的Ca^(2+)信号通路已经成为认知障碍相关疾病研究的热点。目的:研究急性一氧化碳中毒迟发性脑病动物模型中,海马组织内星形胶质细胞和IP3R2、RYR2介导的Ca^(2+)信号的表达情况,探索急性一氧化碳中毒迟发性脑病可能的发病机制。方法:Morris水迷宫实验筛选认知功能合格的C57BL小鼠随机分为对照组、实验组,实验组小鼠采用静态吸入一氧化碳建立急性一氧化碳中毒迟发性脑病模型,对照组小鼠吸入等量空气。造模后第21天,利用Morris水迷宫、苏木精-伊红染色、Western blot、免疫荧光双标法、Ca^(2+)荧光探针检测中毒小鼠行为学及神经元改变、星形胶质细胞特异性标记物胶质纤维酸性蛋白及IP3R2、RYR2受体、星形胶质细胞内Ca^(2+)浓度变化。结果与结论:①Morris水迷宫实验发现与对照组相比,实验组小鼠逃避潜伏期明显延长(P<0.05);②苏木精-伊红染色表明实验组小鼠海马锥体细胞数减少、细胞结构紊乱、细胞核碎裂伴溶解;③免疫荧光检测表明海马区IP3R2、RYR2分别和胶质纤维酸性蛋白存在共表达,且实验组海马区IP3R2、RYR2和胶质纤维酸性蛋白表达均上调(P<0.05);④Western blot检测显示实验组海马区IP3R2、RYR2及胶质纤维酸性蛋白的蛋白表达均增多(P<0.05);⑤Ca^(2+)荧光探针法检测表明实验组小鼠海马区星形胶质细胞内Ca^(2+)浓度明显升高(P<0.05);⑥结果说明,星形胶质细胞可能通过介导IP3R2、RYR2受体影响Ca^(2+)信号,进而使一氧化碳中毒的小鼠认知功能受损,最终导致急性一氧化碳中毒迟发性脑病发生。 展开更多
关键词 急性一氧化碳中毒迟发性脑病 星形胶质细胞 IP3r2受体 rYr2受体 钙信号 认知功能
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Helvacioglu reproducibility index: a new algorithm to evaluate the effects of misalignments on the measurements of retinal nerve fiber layer by spectraldomain OCT
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作者 Firat Helvacioglu Osman Murat Uyar +2 位作者 Sadik Sencan Zeki Tunc Ziya Kapran 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第5期1008-1012,共5页
AIMTo evaluate the effect of misalignment on the measurements of retinal nerve fiber layer (RNFL) by spectral-domain optical coherence tomography (OCT).METHODSA total of 42 eyes from 21 healthy young subjects underwen... AIMTo evaluate the effect of misalignment on the measurements of retinal nerve fiber layer (RNFL) by spectral-domain optical coherence tomography (OCT).METHODSA total of 42 eyes from 21 healthy young subjects underwent RNFL measurements with RTVue spectral-domain OCT (Optovue Inc., Fremont, California, USA). Two baseline measurements with perfectly aligned central circle to the borders of the optic nerve and four misaligned measurements which were misaligned towards to four quadrants were taken. The differences in RNFL between the baseline and misaligned measurements were analyzed with a new algorithm called Helvacioglu reproducibility index (HRI) which is designed to measure the reproducibility of the scans by evaluating the RNFL changes in the four main quadrants.RESULTSThe average RNFL scores of the first two baseline measurements have good correlation (c=0.930) and good reproducibility scores (0.15&#x000b1;0.07). Superior misaligned measurements had significantly lower superior quadrant score and higher inferior quadrant score, similar nasal and little higher temporal scores (P1, P2&#x0003c;0.001, P3=0.553, P4=0.001). Inferior misaligned measurements had significantly higher superior quadrant score and lower inferior quadrant score with similar temporal and little lower nasal scores (P1, P2&#x0003c;0.001, P3=0.315, P4=0.016). Nasal misaligned measurements had significantly higher temporal quadrant score and lower nasal quadrant score with little lower superior and inferior scores (P1, P2, P4&#x0003c;0.001, P3=0.005). Temporal misaligned measurements had significantly higher nasal quadrant score and lower temporal quadrant score with similar superior and little higher inferior scores (P1, P2&#x0003c;0.001, P3=0.943, P4=0.001).CONCLUSIONGood alignment of the central circle to the borders of optic nerve is crucial to have correct and repeatable RNFL measurements. Misalignment to a quadrant resulted in falsely low readings at that quadrant and falsely high readings at the opposite quadrant. 展开更多
关键词 optical coherence tomography retinal nerve fiber layer rEPEATABILITY reproducibility MISALIGNMENT
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