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Strain localization-controlled rock failure using digital volume correlation technology: In situ compression tests on 3D-printed rocklike samples with a single initial flaw
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作者 Yulong Shao Jingwei Yang +4 位作者 Jineon Kim Chen He Jae-Joon Song Hong Yin Junsu Leem 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4329-4348,共20页
The study of rock failure mechanisms is fundamental to geotechnical engineering,as it enhances design quality and mitigates disaster risks.This research employed in situ compression tests on 3D-printed rocklike sample... The study of rock failure mechanisms is fundamental to geotechnical engineering,as it enhances design quality and mitigates disaster risks.This research employed in situ compression tests on 3D-printed rocklike samples with a single flaw,combining Micro-CT scans and a specialized loading device to analyze their behavior.Mechanical properties and failure modes of these printed samples were compared to those of natural flawed sandstones,demonstrating the capability of 3D printing to replicate natural rock characteristics.By reconstructing 3D crack evolution from 2D CT images and applying digital volume correlation(DVC),the study visualized internal strain fields and established a relationship between strain patterns and rock failure.The results reveal that crack initiation consistently occurs at the flaw,advancing into tensile and secondary shear or mixed cracks.For flaw angles(α)ranging from 0°to 45°,the 3D-printed samples exhibited a higher number of newly formed cracks and a faster increase in crack volume with strain.In contrast,for flaw angles of 45°≤α≤90°,the opposite trend was observed.The internal strain field exhibited significant strain localization,with this uneven distribution playing a critical role in sample failure.When the flaw angle was in the range of 0°≤α≤30°,failure was primarily driven by tensile cracks,forming distinct tensile bands.Conversely,for 30°<α≤90°,a combination of tensile and shear cracks dominated the failure,producing both shear and tensile bands in the sample.Additionally,the strain field component ε_(yy) showed a strong correlation with the evolution of internal damage,providing valuable insights into the underlying rock failure mechanisms. 展开更多
关键词 3D printing In situ compression test CT scanning Digital volume correlation(DVC) Damage evolution Strain localization Failure mechanism
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Performance test of digital volume correlation on tracking left atrium motion from cardiac CT
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作者 Zhengduo Zhu Jiaqiu Wang +8 位作者 Hao Wu Minglong Chen Zidun Wang Runxin Fang Xianjue Huang Hujin Xie Han Yu Yuchu Tian Zhiyong Li 《Acta Mechanica Sinica》 2025年第4期156-164,共9页
The accurate assessment of cardiac motion is crucial for diagnosing and monitoring cardiovascular diseases.In this context,digital volume correlation(DVC)has emerged as a promising technique for tracking cardiac motio... The accurate assessment of cardiac motion is crucial for diagnosing and monitoring cardiovascular diseases.In this context,digital volume correlation(DVC)has emerged as a promising technique for tracking cardiac motion from cardiac computed tomography angiographic(CTA)images.This paper presents a comprehensive performance evaluation of the DVC method,specifically focusing on tracking the motion of the left atrium using cardiac CTA data.The study employed a comparative experimental approach while simultaneously optimizing the existing DVC algorithm.Multiple sets of controlled experiments were designed to conduct quantitative analyses on the parameters“radius”and“step”.The results revealed that the optimized DVC algorithm enhanced tracking accuracy within a reasonable computational time.These findings contributed to the understanding of the efficacy and limitations of the DVC algorithm in analyzing heart deformation. 展开更多
关键词 Atrial fibrillation Digital volume correlation Left atrium Cardiac CT Motion tracking
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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS Negative emotion Life satisfaction PLEASURE correlation
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Key role of Levitt’s carbon monoxide breath test in revealing coexistent Gilbert syndrome and erythropoietic protoporphyria:A case report
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作者 Ling-Ling Kang Hou-De Zhang 《World Journal of Clinical Cases》 2026年第1期28-33,共6页
It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and er... It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and erythropoietic protoporphyria(EPP),which has not been previously documented.CASE SUMMARY We present a rare case of coexisting GS and EPP in a 23-year-old Chinese male with a long history of jaundice and recently found splenomegaly.Serial nonspecific hemolysis screening tests yielded inconsistent results,and investigations for common hemolytic etiologies were negative.However,Levitt’s carbon monoxide breath test,which measures erythrocyte lifespan(the gold-standard marker of hemolysis),demonstrated significant hemolysis,revealing a markedly shortened erythrocyte lifespan of 11 days(normal average 120 days).Genetic testing subsequently confirmed EPP with a homozygous ferrochelatase gene mutation and GS with a heterozygous uridine diphosphate glucuronosyl trans-ferase 1A1 gene mutation.CONCLUSION The rapid,non-invasive Levitt’s carbon monoxide breath test resolved the diagnostic challenge posed by a rare and complex cause of hyperbilirubinemia. 展开更多
关键词 Isolated hyperbilirubinemia Erythropoietic protoporphyria Gilbert syndrome HEMOLYSIS Levitt’s carbon monoxide breath test Erythrocyte lifespan Case report
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Correlation between indoor and outdoor corrosion tests for coal train body steel in a coal medium environment 被引量:2
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作者 Jia-liang Song Jun-hang Chen +3 位作者 Pan Yi Na-na Chen Zhao-liang Li Kui Xiao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2022年第9期1495-1504,共10页
Q345B carbon steel as well as Q450NQR1 and S500AW weathering steels were subjected to outdoor exposure corrosion tests in coal environments and indoor periodic immersion accelerated corrosion tests with a simulated co... Q345B carbon steel as well as Q450NQR1 and S500AW weathering steels were subjected to outdoor exposure corrosion tests in coal environments and indoor periodic immersion accelerated corrosion tests with a simulated coal leaching solution.The corrosion kinetics were studied by the weight loss method,and the corrosion morphology and corrosion product composition were observed and analyzed by scanning electron microscopy,energy-dispersive spectroscopy and X-ray diffraction.Afterward,correlation analysis of the indoor and outdoor tests was carried out by the gray correlation analysis method.The results show that the relationship between the corrosion weight loss and corrosion time of the three steels conforms to follow the exponent power law.In particular,Q450NQR1 steel has the best corrosion resistance.The types of corrosion products and the distribution of elements in the rust layer of the three steels are similar in the indoor and outdoor tests.The gray correlation degrees of the three steels in the indoor and outdoor tests are all greater than 0.6;thus,the two corrosion tests have a good correlation.Based on this,the accelerated simulation test method of the coal leaching solution is determined,and life prediction models of three steels in coal leaching solution are established to simulate the corrosion of the bottom board and side board. 展开更多
关键词 Coal train body steel Coal environment-Corrosion Outdoor exposure test Indoor acceleration test correlation
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Correlations between direct and indirect strength test methods 被引量:6
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作者 Kallu Raj Roghanchi Pedram 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期355-360,共6页
The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economic... The difficulties associated with performing direct compression strength tests on rocks lead to the development of indirect test methods for the rock strength assessment. Indirect test methods are simple, more economical, less time-consuming, and easily adaptable to the field. The main aim of this study was to derive correlations between direct and indirect test methods for basalt and rhyolite rock types from Carlin trend deposits in Nevada. In the destructive methods, point load index, block punch index, and splitting tensile strength tests are performed. In the non-destructive methods, Schmidt hammer and ultrasonic pulse velocity tests are performed. Correlations between the direct and indirect compression strength tests are developed using linear and nonlinear regression analysis methods. The results show that the splitting tensile strength has the best correlation with the uniaxial compression strength.Furthermore, the Poisson's ratio has no correlation with any of the direct and indirect test results. 展开更多
关键词 Uniaxial compression strength test Indirect strength test methods correlation Regression analysis
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Correlation method estimation of the modulation signal in the weak equivalence principle test 被引量:2
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作者 Jie Luo Liang-Cheng Shen +2 位作者 Cheng-Gang Shao Qi Liu Hui-Jie Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期136-142,共7页
In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the fre... In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the free oscillation signal and employ the correlation method to estimate the amplitude of the modulation signal. The data analysis of an experiment shows that the uncertainties of amplitude components of the modulation signal obtained by the correlation method are in agreement with those due to white noise. The power spectral density of the modulation signal obtained by the correlation method is about one order higher than the thermal noise limit. It indicates that the correlation method is an effective way to estimate the amplitude of the modulation signal and it is instructive to conduct a high-accuracy WEP test. 展开更多
关键词 weak equivalence principle test correlation method amplitude estimation thermal noise limit
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A New Approach of Studying Correlation between Outdoor Exposure and Indoor Accelerated Corrosion Test for High Polymer Materials 被引量:1
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作者 杨丽霞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期108-112,共5页
The correlation between outdoor exposure and indoor accelerated corrosion test for high polymer materials was investigated according to the variation of the functional group of exposure models aged. Environment aging ... The correlation between outdoor exposure and indoor accelerated corrosion test for high polymer materials was investigated according to the variation of the functional group of exposure models aged. Environment aging intensities at different zones ( Wuhan and Lasa with the same latitude ) and the influences of indoor accelerating factors including water and ultraviolet on weathering performant.e of high polymer materials were also studied by comparing different indoor accelerated corrosion testing results. The experimental results show that : by testing variations of carbonyl exponent of polythene ( which represented the degradation behavior of high polymer materials due to ultraviolet oxidation of douIole bond) and ultraviolet absorbance of polycarbonate (which represented the degradation behavior of high polymer materials due to abevacuation of branched chain ), the degradation behavior of high polymer materials could be studied. Carbonyl exponent of polythene exposed in Wuhan and Lasa for 1 year was equal to that exposed in indoor cycle ultraviolet for 128 h anti 170 It, respectively, the ultraviolet absorbance of polycarbonate exposed in Wuhan for 1 year was equal to that exposed in indoor cycle ultraviolet for 240 h. The ratio of environment aging intensity of Lasa to Wuhan was around 1.2. With the prolongation of cycle accelerated ultraviolet exposure time, the variations of carbonyl exponent of polythene and the ultraviolet absorbance of polycarbonate were in the same shape of first order exponential decay curiae. Accompanied with ultraviolet, the effect of water condensated on the sample on weathering performance of polythene was more .significant than that of polycarbonate. 展开更多
关键词 correlation outdoor exposure indoor accelerated corrnsion testing exposure models
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Modal Test/Calculation Correlation Study on the Lower Crankcase of High-Duty Diesel Engine 被引量:3
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作者 冯慧华 左正兴 +1 位作者 廖日东 张儒华 《Journal of Beijing Institute of Technology》 EI CAS 2004年第1期58-62,共5页
To set up the dynamic FEM model of a high-duty diesel's lower crankcase with sufficient precision, modal correlation research on tested and calculated modes have been fulfilled. MACs between each mode pairs, CoMAC... To set up the dynamic FEM model of a high-duty diesel's lower crankcase with sufficient precision, modal correlation research on tested and calculated modes have been fulfilled. MACs between each mode pairs, CoMACs and ECoMACs on each node of modal testing model have been calculated. On the assistant of modal shape comparison, MACs could afford information about correlating relations between tested and calculated mode groups. CoMACs and ECoMACs have pointed out the direction of structure modification to FEM model. The results of the study show that the analytic model built has a certain degree of accuracy. 展开更多
关键词 DIESEL lower crankcase modal analysis modal correlation FEM
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Tensile strength of sea ice using splitting tests based on the digital image correlation method 被引量:2
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作者 CHEN Xiaodong HE Shuaikang +2 位作者 HE Wenquan WANG Zhaoyu JI Shunying 《Advances in Polar Science》 CSCD 2021年第4期374-381,共8页
The splitting test is a competitive alternative method to study the tensile strength of sea ice owing to its suitability for sampling.However,the approach was questioned to the neglect of local plastic deformation dur... The splitting test is a competitive alternative method to study the tensile strength of sea ice owing to its suitability for sampling.However,the approach was questioned to the neglect of local plastic deformation during the tests.In this study,splitting tests were performed on sea ice,with 32 samples subjected to the regular procedure and 8 samples subjected to the digital image correlation method.The salinity,density,and temperature were measured to determine the total porosity.With the advantage of the digital image correlation method,the full-field deformation of the ice samples could be determined.In the loading direction,the samples mainly deformed at the ice-platen contact area.In the direction vertical to the loading,deformation appears along the central line where the splitting crack occurs.Based on the distribution of the sample deformation,a modified solution was derived to calculate the tensile strength with the maximum load.Based on the modified solution,the tensile strength was further calculated together with the splitting test results.The results show that the tensile strength has a negative correlation with the total porosity,which agrees with previous studies based on uniaxial tension tests. 展开更多
关键词 tensile strength splitting test digital image correlation method ice mechanics sea ice
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Performance and correlation of QuantiFERON-TB Gold, T-SPOT.TB and tuberculin skin test in young children with or exposed to tuberculosis 被引量:4
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作者 Keswadee Lapphra Paninun Srinuchasart +6 位作者 Sansnee Senawong Utane Rungpanich Pinklow Umrod Alan Maleesatharn Nantaka Kongstan Watcharee Lermankul Kulkanya Chokephaibulkit 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第9期423-425,共3页
Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in Bacillus Calmette-Guerin vaccinated young children.Methods:A cross-sectional study was conducted in healthy children... Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in Bacillus Calmette-Guerin vaccinated young children.Methods:A cross-sectional study was conducted in healthy children younger than 5 years who were recently diagnosed with tuberculosis or had recent exposure to active tuberculosis.QuantiFERON-TB Gold,T-SPOT.TB and tuberculin skin test were performed in each patient.Results:Of the 60 children,median age 3.3 years,17 had tuberculosis and 43 had recent tuberculosis exposure.Overall,15(25.0%)children had tuberculin skin test reaction≥10 mm;8(13.3%)were positive by QuantiFERON-TB Gold In-Tube test,and 12(20.0%)by T-SPOT.TB.Nineteen(31.7%)children had at least one positive test.There was a moderate agreement between interferon gamma release assays and tuberculin skin test.Conclusions:The positive rates of interferon gamma release assays and tuberculin skin test were low in young children who were infected with tuberculosis,supporting the management strategy of not testing children younger than 5 years. 展开更多
关键词 Tuberculin skin test QuantiFERON-TB Gold In-Tube test T-SPOT.TB Young children
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High-resolution computed tomography findings in humoral primary immunodeficiencies and correlation with pulmonary function tests 被引量:1
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作者 Lorenzo Cereser Marco De Carli +3 位作者 Paola d'Angelo Elisa Zanelli Chiara Zuiani Rossano Girometti 《World Journal of Radiology》 CAS 2018年第11期172-183,共12页
AIM To compare high-resolution computed tomography(HRCT) findings between humoral primary immunodeficiencies(hPIDs) subtypes; to correlate these findings to pulmonary function tests(PFTs).METHODS We retrospectively id... AIM To compare high-resolution computed tomography(HRCT) findings between humoral primary immunodeficiencies(hPIDs) subtypes; to correlate these findings to pulmonary function tests(PFTs).METHODS We retrospectively identified 52 consecutive adult patients with hPIDs who underwent 64-row HRCT and PFTs at the time of diagnosis. On a per-patient basis, an experienced radiologist recorded airway abnormalities(bronchiectasis,airway wall thickening, mucus plugging, tree-in-bud, and air-trapping) and parenchymal-interstitial abnormalities(consolidations, ground-glass opacities,linear and/or irregular opacities, nodules, and bullae/cysts) found on HRCT.The chi-square test was performed to compare the prevalence of each abnormality among patients with different subtypes of hPIDs. Overall logistic regression analysis was performed to assess whether HRCT findings predicted obstructive and/or restrictive PFTs results(absent-to-mild vs moderate-tosevere).RESULTS Thirty-eight of the 52 patients with hPIDs showed common variable immunodeficiency disorders(CVID), while the remaining 14 had CVID-like conditions(i.e., 11 had isolated IgG subclass deficiencies and 3 had selective IgA deficiencies). The prevalence of most HRCT abnormalities was not significantly different between CVID and CVID-like patients(P > 0.05), except for linear and/or irregular opacities(prevalence of 31.6% in the CVID group and 0 in the CVID-like group; P = 0.0427). Airway wall thickening was the most frequent HRCT abnormality found in both CVID and CVID-like patients(71% of cases in both groups). The presence of tree-in-bud abnormalities was an independent predictor of moderate-to-severe obstructive defects at PFTs(Odds Ratio, OR, of 18.75, P < 0.05), while the presence of linear and/or irregular opacities was an independent predictor of restrictive defects at PFTs(OR = 13.00; P < 0.05).CONCLUSION CVID and CVID-like patients showed similar HRCT findings. Tree-in-bud and linear and/or irregular opacities predicted higher risks of, respectively,obstructive and restrictive defects at PFTs. 展开更多
关键词 BRONCHIECTASIS MULTIDETECTOR computed tomography Common variable IMMUNODEFICIENCY IMMUNOLOGIC deficiency SYNDROMES Respiratory function tests
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Ultraviolet 3D digital image correlation applied for deformation measurement in thermal testing with infrared quartz lamps 被引量:2
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作者 Yali DONG Jiaqing ZHAO Bing PAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第3期1085-1092,共8页
In thermal-structural testing of hypersonic materials and structures,deformation measurement on the front surface of an object directly heated by quartz lamps is highly necessary and very challenging.This work describ... In thermal-structural testing of hypersonic materials and structures,deformation measurement on the front surface of an object directly heated by quartz lamps is highly necessary and very challenging.This work describes a novel front-surface high-temperature deformation measurement technique,which adopts ultraviolet 3D digital image correlation(UV 3D-DIC)to observe and measure the high-temperature deformation fields on front surfaces directly heated by quartz lamps.Compared with existing blue light DIC techniques,the established UV 3D-DIC,which combines UV CCD camera,active UV illumination and bandpass filter imaging,can effectively suppress the strong disturbing light emitted by the quartz lamps and the heated sample itself during heating process.Two experiments were carried out to verify the robustness and accuracy of the developed technique:(1)direct observation of front surfaces of a hypersonic thermal structure sample heated from room temperature to 1050℃,and(2)front-surface thermal stain and coefficient of thermal expansion(CTE)measurement of an Inconel 718 sample up to 800℃.The well matched strain and CTE results with literature data show that UV 3D-DIC system is an effective technique for front-surface deformation measurement and has great potential in characterizing deformation response of hypersonic materials and structures subjected to transient aerodynamic heating. 展开更多
关键词 DEFORMATION DIC Front-surface Quartz lamp heating Ultraviolet 3D digital image correlation
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Performance and correlation of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution 被引量:2
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作者 Keswadee Lapphra Rati Diwitaya +9 位作者 Sansnee Senawong Maneeprang Thovarabha Parnwas Pinnobphun Alan Maleesatharn Nantaka Kongstan Benjawan Khumcha Wanatpreeya Phongsamart Orasri Wittawatmongkol Supattra Rungmaitree Kulkanya Chokephaibulkit 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第10期464-466,共3页
Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution.Methods:A cross-sectional study was conducted in HI... Objective:To evaluate the performance of interferon gamma release assays and tuberculin skin test in HIV-infected children and adolescents with immune reconstitution.Methods:A cross-sectional study was conducted in HIV-infected patients aged 5-18 years receiving antiretroviral treatment with CD4 T-lymphocytes>25%or>500 cells/mm3 for at least 6 months.QuantiF ERON-TB Gold,T-SPOT.TB,and tuberculin skin test were performed in each patient.Results:A total of 50 patients were enrolled with median age of 13.7 years,CD4 counts of 753(IQR:587-989)cells/mm3.Among 27 patients with tuberculosis(16)or tuberculosis exposure(11),8(29.6%)were positive to at least one test,2(7.4%)were positive QuantiFERON-TB Gold,3(11.1%)positive T-SPOT.TB,and 7(25.9%)had tuberculin skin test≥5 mm.Among 23 patients without history of tuberculosis or exposure,all had negative interferon gamma release assays,while 2(8.7%)had positive tuberculin skin test.Conclusions:All tests had low sensitivity despite immune reconstitution. 展开更多
关键词 CHILDREN HIV TB Interferon gamma release assays Tuberculin skin test
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Ulcerative colitis patients in clinical remission demonstrate correlations between fecal immunochemical test results, mucosal healing, and risk of relapse 被引量:3
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作者 Asuka Nakarai Jun Kato +7 位作者 Sakiko Hiraoka Shiho Takashima Daisuke Takei Toshihiro Inokuchi Yuusaku Sugihara Masahiro Takahara Keita Harada Hiroyuki Okada 《World Journal of Gastroenterology》 SCIE CAS 2016年第21期5079-5087,共9页
AIM: To assess the risk of relapse in ulcerative colitis (UC) patients in clinical remission using mucosal status and fecal immunochemical test (FIT) results.METHODS: The clinical outcomes of 194 UC patients in clinic... AIM: To assess the risk of relapse in ulcerative colitis (UC) patients in clinical remission using mucosal status and fecal immunochemical test (FIT) results.METHODS: The clinical outcomes of 194 UC patients in clinical remission who underwent colonoscopy were based on evaluations of Mayo endoscopic subscores (MESs) and FIT results.RESULTS: Patients with an MES of 0 (n = 94, 48%) showed a ten-fold lower risk of relapse than those with an MES of 1-3 (n = 100, 52%) (HR = 0.10, 95%CI: 0.05-0.19). A negative FIT result (fecal hemoglobin concentrations &#x02264; 100 ng/mL) was predictive of patients with an MES of 0, with a sensitivity of 0.94 and a specific of 0.76. Moreover, patients with a negative FIT score had a six-fold lower risk of clinical relapse than those with a positive score (HR = 0.17, 95%CI: 0.10-0.28). Inclusion of the distinguishing parameter, sustaining clinical remission &#x0003e; 12 mo, resulted in an even stronger correlation between negative FIT results and an MES of 0 with respect to the risk of clinical relapse (HR = 0.11, 95%CI: 0.04-0.23).CONCLUSION: Negative FIT results one year or more after remission induction correlate with complete mucosal healing (MES 0) and better prognosis. Performing FIT one year after remission induction may be useful for evaluating relapse risk. 展开更多
关键词 Ulcerative colitis Clinical remission Mucosal healing Mayo endoscopic subscore Quantitative fecal immunochemical test
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Correlation betweenn ucleic acid testing (NAT) and serology in routing blood screening
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《中国输血杂志》 CAS CSCD 2001年第S1期402-,共1页
关键词 ACID NAT correlation betweenn ucleic acid testing and serology in routing blood screening
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Systematic error suppression scheme of the weak equivalence principle test by dual atom interferometers in space based on spectral correlation 被引量:1
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作者 Jian-Gong Hu Xi Chen +2 位作者 Li-Yong Wang Qing-Hong Liao Qing-Nian Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第11期197-202,共6页
Systematic error suppression and test data processing are very important in improving the accuracy and sensitivity of the atom interferometer(AI)-based weak-equivalence-principle(WEP) test in space. Here we present a ... Systematic error suppression and test data processing are very important in improving the accuracy and sensitivity of the atom interferometer(AI)-based weak-equivalence-principle(WEP) test in space. Here we present a spectrum correlation method to investigate the test data of the AI-based WEP test in space by analyzing the characteristics of systematic errors and noises. The power spectrum of the Eotvos coefficient η, systematic errors, and noises in AI-based WEP test in space are analyzed and calculated in detail. By using the method, the WEP violation signal is modulated from direct current(DC) frequency band to alternating current(AC) frequency band. We find that the signal can be effectively extracted and the influence of systematic errors can be greatly suppressed by analyzing the power spectrum of the test data when the spacecraft is in an inertial pointing mode. Furthermore, the relation between the Eotvos coefficient η and the number of measurements is obtained under certain simulated parameters. This method will be useful for both isotopic and nonisotopic AI-based WEP tests in space. 展开更多
关键词 atom interferometer weak equivalence principle spectral correlation systematic error
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ON TESTING THE EQUALITY OF K MULTIPLE AND PARTIAL CORRELATION COEFFICIENTS
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作者 A. K. Gupta Bowling Green State University, USA D. G. Kabe Sf. Mary’s University, USA 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期221-223,共3页
Coutsourides (1980) derives an ad hoc nuisance parameter removal test for testing the equality of two multiple correlation coefficients of two independent p variate normal populations, under the assumption that a samp... Coutsourides (1980) derives an ad hoc nuisance parameter removal test for testing the equality of two multiple correlation coefficients of two independent p variate normal populations, under the assumption that a sample of size n is available from each population. He also extends his ad hoc nuisance parameter removal test to the testing of the equality of two multiple correlation matrices. This paper presents likelihood ratio tests for testing the equality of k multiple correlation coefficients, and also k partial correlation coefficients. 展开更多
关键词 Normal populations multiple correlation coefficients equality testing like-lihood ratio test MOMENTS
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A Correlational Study of Junior College Students' Achievement Test and Reading Comprehension Test Based on Students' Interests
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作者 王晓娜 《英语广场(学术研究)》 2012年第4期119-119,共1页
The present paper is a correlational study of Junior college students' achievement test and reading comprehension test based on students' interests.Through the case study,students' interests should raw muc... The present paper is a correlational study of Junior college students' achievement test and reading comprehension test based on students' interests.Through the case study,students' interests should raw much attention while teachers choose textbooks or teaching materials or design teaching plan. 展开更多
关键词 INTEREST achievement test reading comprehension
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Correlation analysis and causality test between Ludong-Huanghai block and South Japan
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作者 郑建常 蒋海昆 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第4期381-391,共11页
In this paper, we make a comparative analysis and correlation test for the seismic activities in the South Japan and the Ludong-Huanghai block (a secondary tectonic unit in the North China) and approach the relation... In this paper, we make a comparative analysis and correlation test for the seismic activities in the South Japan and the Ludong-Huanghai block (a secondary tectonic unit in the North China) and approach the relationship between the energy release processes of these two areas by using co-integration analysis and Granger causality test for the time series of random variables. The results show that the seismic activities in these two areas are correlative and synchronous to a certain extent, and their release series of cumulative strain energy are contemporaneously correlative. Both energy series are first-order difference stationary processes and there is secular and steady co-integration between them. We make a positive analysis on the first-order difference energy series through Granger causality test based on vector error correction (VEC) model and find there is unilateral Granger causality and prominent co-integration between the two energy release processes. 展开更多
关键词 South Japan Ludong-Huanghai block correlation co-integration analysis Granger causality test
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