Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th...Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT＆E are also presented.展开更多
For optimal design of constant stress accelerated life test（CSALT） with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT desig...For optimal design of constant stress accelerated life test（CSALT） with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions.展开更多
Objective:To look into the glucose tolerance test characteristics and determine complications in non-gestational diabetes pregnant subjects.Methods:From 2006 to 2009 all non-gestational diabetes mellitus(non-CDM)pregn...Objective:To look into the glucose tolerance test characteristics and determine complications in non-gestational diabetes pregnant subjects.Methods:From 2006 to 2009 all non-gestational diabetes mellitus(non-CDM)pregnant women who delivered macrosomia at the North Australia's Townsville Hospital were retrospectively reviewed by extracting data from clinical record.Glucose tolerance tests results were analysed in the light of an earlier diagnosis of non-GDM.Results:Ninety-one non-CDM mothers with macrosomia were studied and compared with 41normoglycemic subjects without macrosomia.Of the subjects with non-GDM macrosomia,45(49.4%)had normal SO g glucose challenge test(GCT)without further testing,another 8(8.8%)had abnormal GCT but normal 75 g oral glucose tolerance test(OGTT).A total of 4(4.4%)subjects had normal GCT and OGTT.Interestingly.14 out of 16(87.5%)subjects who were tested with OGTT owing to past history of macrosomia had normal results but delivered macrosomic babies.Only 12 subjects had both GCT and OGTT,the rest of the cohort had either of the two tests.Subjects with non-CDM macrosomia had higher frequency of neonatal hypoglycaemia 34%as compared to 10%in nonmacrosomic babies(P=0.003).Other feto-maternal complications were similar in both groups.Conclussions:No significant pattern of glucose tolerance characteristics was identified in nonGDM mothers with macrosomic babies.In spite of being normoglycemic significant neonatal hypoglycaemia was recorded in non-GDM macrosomic babies.Further prospective studies on a larger population are needed to verify our findings.展开更多
A control method for Multi-Input Multi-Output（MIMO） non-Gaussian random vibration test with cross spectra consideration is proposed in the paper. The aim of the proposed control method is to replicate the specified ...A control method for Multi-Input Multi-Output（MIMO） non-Gaussian random vibration test with cross spectra consideration is proposed in the paper. The aim of the proposed control method is to replicate the specified references composed of auto spectral densities, cross spectral densities and kurtoses on the test article in the laboratory. It is found that the cross spectral densities will bring intractable coupling problems and induce difficulty for the control of the multioutput kurtoses. Hence, a sequential phase modification method is put forward to solve the coupling problems in multi-input multi-output non-Gaussian random vibration test. To achieve the specified responses, an improved zero memory nonlinear transformation is utilized first to modify the Fourier phases of the signals with sequential phase modification method to obtain one frame reference response signals which satisfy the reference spectra and reference kurtoses. Then, an inverse system method is used in frequency domain to obtain the continuous stationary drive signals. At the same time, the matrix power control algorithm is utilized to control the spectra and kurtoses of the response signals further. At the end of the paper, a simulation example with a cantilever beam and a vibration shaker test are implemented and the results support the proposed method very well.展开更多
Deformation behavior of non-rigid airships in wind tunnel tests is studied by considering three factors, including internal pressure, flow velocity and angle of attack. Fiber Bragg grating strain sensors are used to m...Deformation behavior of non-rigid airships in wind tunnel tests is studied by considering three factors, including internal pressure, flow velocity and angle of attack. Fiber Bragg grating strain sensors are used to measure the deformation of non-rigid airships. Wind tunnel tests in the case of different flow velocities and angles of attack are conducted. The measurement results reveal that the airship deformation is in proportion to internal pressure. For the tensile region,the airship deformation is in proportion to flow velocity. Effects of angle of attack on structural deformation are more complicated and there is no clear relationship existing between airship deformation and angle of attack.展开更多
AIM To explore the effect of alanine aminotransferase(ALT) on the performance of non-invasive fibrosis tests in chronic hepatitis B(CHB) patients. METHODS A total of 599 treatment-naive and biopsy-proven CHB patients ...AIM To explore the effect of alanine aminotransferase(ALT) on the performance of non-invasive fibrosis tests in chronic hepatitis B(CHB) patients. METHODS A total of 599 treatment-naive and biopsy-proven CHB patients were included in the study. The cohort was divided into the following three groups: Normal ALT(ALT ≤ 40), slightly elevated ALT(40 < ALT ≤ 80) and elevated ALT(ALT > 80). The diagnostic performance of five common non-invasive fibrosis tests for liver fibrosis(stages S2-4), including the aspartate aminotransferase(AST)-to-platelet(PLT) ratio index(APRI), fibrosis index based on 4 factors(FIB-4), King's score, Forns index and gamma-glutamyl transpeptidase(GGT)-to-PLT ratio(GPR), were evaluated for each group. RESULTS Higher ALT levels were associated with higher non-invasive fibrosis test scores. Patients with the same fibrosis stage but higher ALT levels showed higher noninvasive test scores. The areas under the receiver operating characteristics curves(AUROCs) of the noninvasive tests for prediction of ≥ S2 were higher for patients with ALT ≤ 40 U/L(range 0.705-0.755) and 40 < ALT ≤ 80 U/L(range 0.726-0.79) than for patients with ALT > 80 U/L(range 0.604-0.701). The AUROCs for predicting ≥ S3 and S4 were higher in patients with ALT ≤ 40 U/L(range 0.736-0.814 for ≥ S3, 0.79-0.833 for S4) than in patients with 40 < ALT ≤ 80 U/L(range 0.732-0.754 for ≥ S3, range 0.626-0.723 for S4) and ALT > 80 U/L(range 0.7-0.784 for ≥ S3, range 0.662-0.719 for S4). The diagnostic accuracy of the non-invasive tests decreased in a stepwise manner with the increase in ALT.CONCLUSION ALT has a significant effect on the diagnostic performance of non-invasive fibrosis tests. The ALT level should be considered before performing these noninvasive tests.展开更多
Introduction: Over the past few years, molecular targeted therapies have been?emerging for the treatment of metastatic non-small cell lung cancer (NSCLC).?Targeted therapy is associated with improved outcomes in patie...Introduction: Over the past few years, molecular targeted therapies have been?emerging for the treatment of metastatic non-small cell lung cancer (NSCLC).?Targeted therapy is associated with improved outcomes in patients with identified gene alterations, and national guidelines recommend routine biomarker testing. This study evaluated real-world rates of documented epidermal growth factor receptor (EGFR) mutation and other biomarker testing in patients with advanced NSCLC over time.?Methods: Adult patients with Stage IV NSCLC were identified between January 1, 2012 and May 31, 2017 from the US Oncology Network iKnowMedTM?electronic health records. Patients were examined overall and by histology. Rates of documented EGFR mutation and other biomarker testing were calculated. Multivariable regression analyses were conducted to identify characteristics associated with documented biomarker testing. Results: A total of 14,461 patients were identified: median age was 69.3 years, 52.3% were male, 14.6% were nonsmokers, and 64.7% had non-squamous histology.?EGFR mutation testing rates were 35.5%?overall, with an increase in rates seen over time: 30.0% in 2012 to 44.0% in 2016?(p??0.001).?Anaplastic lymphoma kinase (ALK), c-ros oncogene 1 (ROS1), and programmed death-ligand 1 (PD-L1) mutation testing rates were 32.9%, 5.7%, and 5.7%, respectively. More recent diagnosis year, non-squamous histology, larger practice size, and nonsmoking status were strongly associated with higher documented EGFR and ALK mutation testing rates.?Conclusions: EGFR mutation testing rates steadily increased over time, but remained less than 50%, with lower mutation testing rates reported for ALK, ROS1, and PD-L1, suggesting that opportunities exist to improve education on testing for biomarkers in NSCLC.展开更多
We study the relationship between energy consumption and economic growth in the case of USA by using an asymmetric ARDL bounds test approach to achieve the actual model. The quarterly data set covers the period of 197...We study the relationship between energy consumption and economic growth in the case of USA by using an asymmetric ARDL bounds test approach to achieve the actual model. The quarterly data set covers the period of 1973:1- 2013:4. The findings indicate that the effect of energy consumption is asymmetric in the long term but not in the short term. In the long run, the effect of negative component of energy consumption on economic growth is small and statistically insignificant. The coefficient of the positive component of energy consumption is found about 0.9 and statistically significant at 1% level. We conclude that energy saving policies such as technological progress and organizational rearrangements may have the dimmer effect for the impact of a negative component of energy consumption and the booster effect for impact of the positive component of energy consumption. Thus, energy saving policy should be tightly followed by the goal of high economic growth.展开更多
Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,...Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,astronomy applications,semiconductor technology and superconductiong electronics. In this article,we present a reviewof the principle and performance of typical terahertz sources,detectors and non-destructive testing applications. On this basis,the newdevelopment and trends of terahertz radiation detectors are also discussed.展开更多
In view of the anisotropy,heterogeneity and stress-sensitive permeability in low permeability reservoirs,an analytical well test model was established by introducing the concept of permeability modulus.This model cons...In view of the anisotropy,heterogeneity and stress-sensitive permeability in low permeability reservoirs,an analytical well test model was established by introducing the concept of permeability modulus.This model considered the permeability stress-sensitivity,wellbore storage effect,and the skin effect.The perturbation technique and Laplace transformation were used to solve the mathematical model analytically in Laplace space,and the bottom-hole pressure type curves were plotted and analyzed in real space by using the Stehfest numerical inversion.展开更多
The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-s...The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-soft clayey soils gains more attention.Both shear strength and electrical impedance were measured experimentally for both untreated and treated ultra-soft clayey soils.The shear strength of untreated ultra-soft clayey soil reached 0.17 kPa for 10% bentonite content,while the shear strengths increased to 0.27 kPa and 6.7 kPa for 10% bentonite content treated with 2% lime and 10% polymer,respectively.The electrical impedance of the ultra-soft clayey soil has shown a significant decrease from 1.6 kΩ to 0.607 kΩ when the bentonite content increased from 2% to 10% at a frequency of 300 kHz.The10%lime and 10% polymer treatments have decreased the electrical impedances of ultra-soft clayey soil with 10%bentonite from 0.607 kΩ to 0.12 kΩ and 0.176 kΩ,respectively,at a frequency of 300 kHz.A new mathematical model has been accordingly proposed to model the non-destructive electrical impedancefrequency relationship for both untreated and treated ultra-soft clayey soils.The new model has shown a good agreement with experimental data with coefficient of determination（R;）up to 0.99 and root mean square error（RMSE） of 0.007 kΩ.展开更多
Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine treatment.Methods Non-invasive micro-test techniques were used to study Ca2+ in iso...Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine treatment.Methods Non-invasive micro-test techniques were used to study Ca2+ in isolated OHCs in adult guinea pigs.Results Four types of Ca2+ transport were identified in OHCs on basilar membrane tissue fragments:influx at the head of with efflux at the bottom(type 1):efflux at the head of OHCs with influx at the bottom(type 2);influx at the both head and bottom(type 3);and efflux at the both head and bottom(type 4).However,only type 1 and type 3 of Ca2+ ion transport were detected in the cochlea.We propose that Ca2+ ion transport exists in adult guinea pig cochlear OHCs in resting state and is variable.Ca2 + flow in OHC can be inhibited by Nimodipine in resting state.展开更多
The nondestructive testing of anti slide pile usually adopts low strain method, high strain method and acoustic transmission method. Low strain detection method is very effective in finding major defects, but it is no...The nondestructive testing of anti slide pile usually adopts low strain method, high strain method and acoustic transmission method. Low strain detection method is very effective in finding major defects, but it is not foolproof;In revealing the integrity of piles, mutual comparison can better explain the problem. The test results can only be used as a reference for the determination of pile defects, and the pile cannot be determined as unqualified only by the results of integrity test. The inspector must fully grasp the pile foundation construction and geological conditions in order to make the most reasonable interpretation of the test results.展开更多
Proper diagnosis in the pediatric population is required to eradicate Helicobacter pylori (H. pylori) and prevent gastric cancer. Our aim was to assess the performance of non-invasive tests to diagnose H. pylori infec...Proper diagnosis in the pediatric population is required to eradicate Helicobacter pylori (H. pylori) and prevent gastric cancer. Our aim was to assess the performance of non-invasive tests to diagnose H. pylori infection in pediatric patients. A retrospective analysis was performed on 141 pediatric patients requiring endoscopic evaluation and diagnostic tests for H. pylori infection to define the cause of abdominal symptoms. Non-invasive tests included the 13C-urea breath test (UBT), a monoclonal stool antigen test using enzyme-linked immuno-sorbent assay (mSAT), and a serum immunoglobulin G antibody test using antigens derived from Japanese individuals (S-Ab). This study investigated sensitivity, specificity, likelihood ratios for a positive and a negative test (LR+ and LR-), and accuracy of non-invasive tests, in comparison with invasive tests. Eighty two of 141 patients (58%) were recognized as H. pylori positive by invasive methods. When UBT, mSAT or S-Ab were analyzed, all were found to be effective over 94% accurate. Specificity ranged between 86.7% and 95.8%, and sensitivity ranged between 93.8% and 97.1%. When subjects were stratified into three distinct age groups, the best performance was achieved for 1-6 years old with mSAT at 100% for sensitivity, specificity, and accuracy. S-Ab yielded the best results for children 7-12 years old and the UBT test performed best for 13-18 years old. These results demonstrate the utility of UBT, mSAT, and S-Ab non-invasive tests in diagnosing H. pylori but suggest that certain tests may be optimal for children of distinct ages. Three non-invasive tests, UBT, mSAT and S-Ab showed sufficient sensitivity, specificity and accuracy for the initial diagnosis of H. pylori infection among pediatric patients. Non-invasive tests may contribute to achieving minimum invasive diagnosis with combining with a histological test and a culture test in children.展开更多
In this paper, an optical fiber sensor is designed by using optical Faraday effect. It is composed of fiber collimator, polarizer, magneto-optical crystal and mirror. Based on the magnetic flux leakage (MFL) theory, T...In this paper, an optical fiber sensor is designed by using optical Faraday effect. It is composed of fiber collimator, polarizer, magneto-optical crystal and mirror. Based on the magnetic flux leakage (MFL) theory, The optical fiber sensor was placed between two permanent magnets with the N-pole. Therefore, the optical fiber sensing system was built to detect the defective ferromagnetic objects. Theoretical and experimental studies shown that the system can identify a little defects, such as irons’ blind hole (diameter φ =?3mm , depth t = 4mm?), irons’ grooves (length l= 30mm , width?ω = 10mm ), hole (φ?=?3mm ) and crackle etc. The system has the characteristics of small size, high sensitivity, fast signal response and high resolution. In terms of the defective oil and gas pipelines detection, The optical fiber sensing system is used in non-destructive testing, which will be valuable and meaningful.展开更多
[Objective]The aim was to improve the quality of the egg in favour of producers and business operators according to the market demand to take scientific feeding and management.[Methods]This paper discussed the researc...[Objective]The aim was to improve the quality of the egg in favour of producers and business operators according to the market demand to take scientific feeding and management.[Methods]This paper discussed the research progress of using machine vision,optical properties,and acoustic resonance technology in the egg quality nondestructive testing. [Results]Egg quality indicators directly affect their edible quality and quality levels. [Conclusion]Egg quality test has practical value and practical significance.展开更多
Introduction: To achieve viral suppression and reduce vertical transmission of HIV, more than eighty percent of pregnant or breastfeeding women in Zambia have been started on combined ART using the Test and Treat mode...Introduction: To achieve viral suppression and reduce vertical transmission of HIV, more than eighty percent of pregnant or breastfeeding women in Zambia have been started on combined ART using the Test and Treat model. However, Chawama First Level Hospital in Lusaka had records which showed that 32 percent of pregnant or breastfeeding women were non-adherent to combined anti-retroviral therapy (cART). Method: A mixed-method study was conducted to establish predictors of non-adherence to cART by women in the Test and Treat model of care. For the quantitative component, 92 consenting Pregnant and breastfeeding women were randomly drawn from ART defaulter register and a semi-structured questionnaire was administered. Multiple logistic regression was conducted to improve predictive power and control for confounders. Quantitative Results: The mean age was 28years. The study established that housewives were 84 percent less likely to be non-adherent [AOR 0.16;95% CI 0.12, 0.36] compared to women who were formally employed with a statistically significant P-value of 0.04. Pregnant or breastfeeding women who were several months away from home were 84.9 percent more likely to be non-adherent [AOR 15.11;95% CI 13.9, 16.4] compared to women who had travelled away from home for several days. The associated P-value was 0.03. The study also established that pregnant and breastfeeding women who were counselled in individually enclosed units were 91 percent less likely to be non-adherent compared to those who were counselled in an open space as a group [AOR 0.09;95% CI 0.02, 0.53] with an associated P-value of 0.01. Conclusion: The study established that predictors of non-adherence to cART among pregnant and breastfeeding women were: being a working-class client;being away from home or usual clinic for several months;being counselled in open spaces, and negative staff attitude. Therefore, researcher can conclusively say that predictors of non-adherence to cART can be solved by training and re-training of health workers in Patient-Centred Care Model for effective patient engagement. Women should be counselled in private rooms. Furthermore, an improvement in patient’s tracking system by the use of smart-care-cards for pregnant and breastfeeding women countrywide can reduce patient’s non-adherence to cART.展开更多
The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative ...The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative model has been set up to investigate effect of the thickness of coating and/or substrate on the detectibility of debonging in SSCPs.Two parameters,namely the maximum defect temperature difference and defect appearing index,are defined to evaluate the detectivity of defects,and their computational methods and formulas are given respectively.The preliminary changing tendency of the maximum defect temperature difference and defect appearing index with the thickness of coating and/or substrate is found by numerical simulation.展开更多
An essentially new method for non-destructive testing of elastic electrically conductive rods using non-vortex electromagnetic induction is proved theoretically. An experimental technique for defining a location of a ...An essentially new method for non-destructive testing of elastic electrically conductive rods using non-vortex electromagnetic induction is proved theoretically. An experimental technique for defining a location of a cross crack is offered.展开更多
This paper discusses the experimental results of concurrently measured Electrical and Acoustic Emissions in order to evaluate the mechanical health status of cement mortar beams subjected to three-point bending mechan...This paper discusses the experimental results of concurrently measured Electrical and Acoustic Emissions in order to evaluate the mechanical health status of cement mortar beams subjected to three-point bending mechanical tests. In particular, the Electrical Resistance and the Electrical Current emissions are recorded concurrent with Acoustic Emissions and the experimental results are discussed under the concept of crack initiation and propagation processes. For the first time, the electrodes that are used for conducting the measurements are placed in the bulk of the specimen, near the tensile zone, during its preparation. The damage evolution is examined by monitoring the fractional change of the Electrical Resistance and the variation of the Electrical Current in combination with the Acoustic Emission recordings.展开更多
基金Ministry of Higher Education of Malaysia for funding the project on PEC NDT at IIUM through the research grant FRGS16-059-0558supported by the National Natural Science Foundation of China under research grants 51677187 and 51307172
文摘Pulsed eddy current （PEC） non-destructive test- ing and evaluation （NDT＆E） has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT＆E are also presented.
基金supported by National Natural Science Foundation of China(Grant Nos. 50935002, 51075370, 51105341)National Hi-tech Research and Development Program of China(863 Program, Grant No. 2007AA04Z409)+1 种基金the Technology Foundation of National Defense ProgramZhejiang Provincial Natural Science Foundation of China (Grant Nos. Y1100777, Y1080762)
文摘For optimal design of constant stress accelerated life test（CSALT） with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions.
基金Supported in part by funds from Australia's James Cook University research infrastructure block grant(Grant No.RIBG 09-2009)
文摘Objective:To look into the glucose tolerance test characteristics and determine complications in non-gestational diabetes pregnant subjects.Methods:From 2006 to 2009 all non-gestational diabetes mellitus(non-CDM)pregnant women who delivered macrosomia at the North Australia's Townsville Hospital were retrospectively reviewed by extracting data from clinical record.Glucose tolerance tests results were analysed in the light of an earlier diagnosis of non-GDM.Results:Ninety-one non-CDM mothers with macrosomia were studied and compared with 41normoglycemic subjects without macrosomia.Of the subjects with non-GDM macrosomia,45(49.4%)had normal SO g glucose challenge test(GCT)without further testing,another 8(8.8%)had abnormal GCT but normal 75 g oral glucose tolerance test(OGTT).A total of 4(4.4%)subjects had normal GCT and OGTT.Interestingly.14 out of 16(87.5%)subjects who were tested with OGTT owing to past history of macrosomia had normal results but delivered macrosomic babies.Only 12 subjects had both GCT and OGTT,the rest of the cohort had either of the two tests.Subjects with non-CDM macrosomia had higher frequency of neonatal hypoglycaemia 34%as compared to 10%in nonmacrosomic babies(P=0.003).Other feto-maternal complications were similar in both groups.Conclussions:No significant pattern of glucose tolerance characteristics was identified in nonGDM mothers with macrosomic babies.In spite of being normoglycemic significant neonatal hypoglycaemia was recorded in non-GDM macrosomic babies.Further prospective studies on a larger population are needed to verify our findings.
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Postgraduate Research & Practice Innovation Program of Jiangsu Province (No. KYCX17_0234)
文摘A control method for Multi-Input Multi-Output（MIMO） non-Gaussian random vibration test with cross spectra consideration is proposed in the paper. The aim of the proposed control method is to replicate the specified references composed of auto spectral densities, cross spectral densities and kurtoses on the test article in the laboratory. It is found that the cross spectral densities will bring intractable coupling problems and induce difficulty for the control of the multioutput kurtoses. Hence, a sequential phase modification method is put forward to solve the coupling problems in multi-input multi-output non-Gaussian random vibration test. To achieve the specified responses, an improved zero memory nonlinear transformation is utilized first to modify the Fourier phases of the signals with sequential phase modification method to obtain one frame reference response signals which satisfy the reference spectra and reference kurtoses. Then, an inverse system method is used in frequency domain to obtain the continuous stationary drive signals. At the same time, the matrix power control algorithm is utilized to control the spectra and kurtoses of the response signals further. At the end of the paper, a simulation example with a cantilever beam and a vibration shaker test are implemented and the results support the proposed method very well.
基金supported by the National Natural Science Foundation of China(Nos.11472276,11332011 and 11502268)
文摘Deformation behavior of non-rigid airships in wind tunnel tests is studied by considering three factors, including internal pressure, flow velocity and angle of attack. Fiber Bragg grating strain sensors are used to measure the deformation of non-rigid airships. Wind tunnel tests in the case of different flow velocities and angles of attack are conducted. The measurement results reveal that the airship deformation is in proportion to internal pressure. For the tensile region,the airship deformation is in proportion to flow velocity. Effects of angle of attack on structural deformation are more complicated and there is no clear relationship existing between airship deformation and angle of attack.
基金Supported by the Liaoning Provincial Science and Technology Key Project for Translational Medicine,No.2014225020Outstanding Scientific Fund of Shengjing Hospital,No.201102+1 种基金Liaoning Provincial Science and Technology Key Project for Translational Medicine,No.2016509National Science and Technology Major Project,Nos.2017ZX10201201,2017ZX10202202,2017ZX10202203
文摘AIM To explore the effect of alanine aminotransferase(ALT) on the performance of non-invasive fibrosis tests in chronic hepatitis B(CHB) patients. METHODS A total of 599 treatment-naive and biopsy-proven CHB patients were included in the study. The cohort was divided into the following three groups: Normal ALT(ALT ≤ 40), slightly elevated ALT(40 < ALT ≤ 80) and elevated ALT(ALT > 80). The diagnostic performance of five common non-invasive fibrosis tests for liver fibrosis(stages S2-4), including the aspartate aminotransferase(AST)-to-platelet(PLT) ratio index(APRI), fibrosis index based on 4 factors(FIB-4), King's score, Forns index and gamma-glutamyl transpeptidase(GGT)-to-PLT ratio(GPR), were evaluated for each group. RESULTS Higher ALT levels were associated with higher non-invasive fibrosis test scores. Patients with the same fibrosis stage but higher ALT levels showed higher noninvasive test scores. The areas under the receiver operating characteristics curves(AUROCs) of the noninvasive tests for prediction of ≥ S2 were higher for patients with ALT ≤ 40 U/L(range 0.705-0.755) and 40 < ALT ≤ 80 U/L(range 0.726-0.79) than for patients with ALT > 80 U/L(range 0.604-0.701). The AUROCs for predicting ≥ S3 and S4 were higher in patients with ALT ≤ 40 U/L(range 0.736-0.814 for ≥ S3, 0.79-0.833 for S4) than in patients with 40 < ALT ≤ 80 U/L(range 0.732-0.754 for ≥ S3, range 0.626-0.723 for S4) and ALT > 80 U/L(range 0.7-0.784 for ≥ S3, range 0.662-0.719 for S4). The diagnostic accuracy of the non-invasive tests decreased in a stepwise manner with the increase in ALT.CONCLUSION ALT has a significant effect on the diagnostic performance of non-invasive fibrosis tests. The ALT level should be considered before performing these noninvasive tests.
文摘Introduction: Over the past few years, molecular targeted therapies have been?emerging for the treatment of metastatic non-small cell lung cancer (NSCLC).?Targeted therapy is associated with improved outcomes in patients with identified gene alterations, and national guidelines recommend routine biomarker testing. This study evaluated real-world rates of documented epidermal growth factor receptor (EGFR) mutation and other biomarker testing in patients with advanced NSCLC over time.?Methods: Adult patients with Stage IV NSCLC were identified between January 1, 2012 and May 31, 2017 from the US Oncology Network iKnowMedTM?electronic health records. Patients were examined overall and by histology. Rates of documented EGFR mutation and other biomarker testing were calculated. Multivariable regression analyses were conducted to identify characteristics associated with documented biomarker testing. Results: A total of 14,461 patients were identified: median age was 69.3 years, 52.3% were male, 14.6% were nonsmokers, and 64.7% had non-squamous histology.?EGFR mutation testing rates were 35.5%?overall, with an increase in rates seen over time: 30.0% in 2012 to 44.0% in 2016?(p??0.001).?Anaplastic lymphoma kinase (ALK), c-ros oncogene 1 (ROS1), and programmed death-ligand 1 (PD-L1) mutation testing rates were 32.9%, 5.7%, and 5.7%, respectively. More recent diagnosis year, non-squamous histology, larger practice size, and nonsmoking status were strongly associated with higher documented EGFR and ALK mutation testing rates.?Conclusions: EGFR mutation testing rates steadily increased over time, but remained less than 50%, with lower mutation testing rates reported for ALK, ROS1, and PD-L1, suggesting that opportunities exist to improve education on testing for biomarkers in NSCLC.
文摘We study the relationship between energy consumption and economic growth in the case of USA by using an asymmetric ARDL bounds test approach to achieve the actual model. The quarterly data set covers the period of 1973:1- 2013:4. The findings indicate that the effect of energy consumption is asymmetric in the long term but not in the short term. In the long run, the effect of negative component of energy consumption on economic growth is small and statistically insignificant. The coefficient of the positive component of energy consumption is found about 0.9 and statistically significant at 1% level. We conclude that energy saving policies such as technological progress and organizational rearrangements may have the dimmer effect for the impact of a negative component of energy consumption and the booster effect for impact of the positive component of energy consumption. Thus, energy saving policy should be tightly followed by the goal of high economic growth.
基金supported by the Cooperative Innovation Center of Terahertz Science , the National Basic Research Program of China (Grant No. 2014CB339800)the National Natural Science Foundation of China (Grant Nos. 61138001, 61420106006)+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University (grant No. IRT13033)the Major National Development Project of Scientific Instruments and Equipment of China (Grant No. 2011YQ150021)
文摘Optoelectronic terahertz generation and detection play a key role in the applications of non-destructive testing,which involves different areas such as physics,biological,material science,imaging,explosions detection,astronomy applications,semiconductor technology and superconductiong electronics. In this article,we present a reviewof the principle and performance of typical terahertz sources,detectors and non-destructive testing applications. On this basis,the newdevelopment and trends of terahertz radiation detectors are also discussed.
基金support from the National 973 Program (Grant No. 2006CB705808)PetroChina Young and Middle Aged People Innovation Fund (Grant No. 07E1016)+1 种基金PetroChina Science & Technology Innovation Fund (Grant No. 2008D-5006-02-09)Science & Technology Innovation Fund of Southwest Petroleum University (Grant No. 2007XJZ010)
文摘In view of the anisotropy,heterogeneity and stress-sensitive permeability in low permeability reservoirs,an analytical well test model was established by introducing the concept of permeability modulus.This model considered the permeability stress-sensitivity,wellbore storage effect,and the skin effect.The perturbation technique and Laplace transformation were used to solve the mathematical model analytically in Laplace space,and the bottom-hole pressure type curves were plotted and analyzed in real space by using the Stehfest numerical inversion.
基金supported by the Center for Innovative Grouting Materials and Technology (CIGMAT) at the University of Houston, Texas, USA
文摘The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such material.Hence,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-soft clayey soils gains more attention.Both shear strength and electrical impedance were measured experimentally for both untreated and treated ultra-soft clayey soils.The shear strength of untreated ultra-soft clayey soil reached 0.17 kPa for 10% bentonite content,while the shear strengths increased to 0.27 kPa and 6.7 kPa for 10% bentonite content treated with 2% lime and 10% polymer,respectively.The electrical impedance of the ultra-soft clayey soil has shown a significant decrease from 1.6 kΩ to 0.607 kΩ when the bentonite content increased from 2% to 10% at a frequency of 300 kHz.The10%lime and 10% polymer treatments have decreased the electrical impedances of ultra-soft clayey soil with 10%bentonite from 0.607 kΩ to 0.12 kΩ and 0.176 kΩ,respectively,at a frequency of 300 kHz.A new mathematical model has been accordingly proposed to model the non-destructive electrical impedancefrequency relationship for both untreated and treated ultra-soft clayey soils.The new model has shown a good agreement with experimental data with coefficient of determination（R;）up to 0.99 and root mean square error（RMSE） of 0.007 kΩ.
文摘Objective To test Calcium ion(Ca2+) flow at the head and end of outer hair cells(OHCs) in resting state and in response to Nimodipine treatment.Methods Non-invasive micro-test techniques were used to study Ca2+ in isolated OHCs in adult guinea pigs.Results Four types of Ca2+ transport were identified in OHCs on basilar membrane tissue fragments:influx at the head of with efflux at the bottom(type 1):efflux at the head of OHCs with influx at the bottom(type 2);influx at the both head and bottom(type 3);and efflux at the both head and bottom(type 4).However,only type 1 and type 3 of Ca2+ ion transport were detected in the cochlea.We propose that Ca2+ ion transport exists in adult guinea pig cochlear OHCs in resting state and is variable.Ca2 + flow in OHC can be inhibited by Nimodipine in resting state.
文摘The nondestructive testing of anti slide pile usually adopts low strain method, high strain method and acoustic transmission method. Low strain detection method is very effective in finding major defects, but it is not foolproof;In revealing the integrity of piles, mutual comparison can better explain the problem. The test results can only be used as a reference for the determination of pile defects, and the pile cannot be determined as unqualified only by the results of integrity test. The inspector must fully grasp the pile foundation construction and geological conditions in order to make the most reasonable interpretation of the test results.
文摘Proper diagnosis in the pediatric population is required to eradicate Helicobacter pylori (H. pylori) and prevent gastric cancer. Our aim was to assess the performance of non-invasive tests to diagnose H. pylori infection in pediatric patients. A retrospective analysis was performed on 141 pediatric patients requiring endoscopic evaluation and diagnostic tests for H. pylori infection to define the cause of abdominal symptoms. Non-invasive tests included the 13C-urea breath test (UBT), a monoclonal stool antigen test using enzyme-linked immuno-sorbent assay (mSAT), and a serum immunoglobulin G antibody test using antigens derived from Japanese individuals (S-Ab). This study investigated sensitivity, specificity, likelihood ratios for a positive and a negative test (LR+ and LR-), and accuracy of non-invasive tests, in comparison with invasive tests. Eighty two of 141 patients (58%) were recognized as H. pylori positive by invasive methods. When UBT, mSAT or S-Ab were analyzed, all were found to be effective over 94% accurate. Specificity ranged between 86.7% and 95.8%, and sensitivity ranged between 93.8% and 97.1%. When subjects were stratified into three distinct age groups, the best performance was achieved for 1-6 years old with mSAT at 100% for sensitivity, specificity, and accuracy. S-Ab yielded the best results for children 7-12 years old and the UBT test performed best for 13-18 years old. These results demonstrate the utility of UBT, mSAT, and S-Ab non-invasive tests in diagnosing H. pylori but suggest that certain tests may be optimal for children of distinct ages. Three non-invasive tests, UBT, mSAT and S-Ab showed sufficient sensitivity, specificity and accuracy for the initial diagnosis of H. pylori infection among pediatric patients. Non-invasive tests may contribute to achieving minimum invasive diagnosis with combining with a histological test and a culture test in children.
文摘In this paper, an optical fiber sensor is designed by using optical Faraday effect. It is composed of fiber collimator, polarizer, magneto-optical crystal and mirror. Based on the magnetic flux leakage (MFL) theory, The optical fiber sensor was placed between two permanent magnets with the N-pole. Therefore, the optical fiber sensing system was built to detect the defective ferromagnetic objects. Theoretical and experimental studies shown that the system can identify a little defects, such as irons’ blind hole (diameter φ =?3mm , depth t = 4mm?), irons’ grooves (length l= 30mm , width?ω = 10mm ), hole (φ?=?3mm ) and crackle etc. The system has the characteristics of small size, high sensitivity, fast signal response and high resolution. In terms of the defective oil and gas pipelines detection, The optical fiber sensing system is used in non-destructive testing, which will be valuable and meaningful.
基金Funded by Natural fund project of Shanxi Normal University(872014)Functional Food Project of Shanxi Normal University(870340)
文摘[Objective]The aim was to improve the quality of the egg in favour of producers and business operators according to the market demand to take scientific feeding and management.[Methods]This paper discussed the research progress of using machine vision,optical properties,and acoustic resonance technology in the egg quality nondestructive testing. [Results]Egg quality indicators directly affect their edible quality and quality levels. [Conclusion]Egg quality test has practical value and practical significance.
文摘Introduction: To achieve viral suppression and reduce vertical transmission of HIV, more than eighty percent of pregnant or breastfeeding women in Zambia have been started on combined ART using the Test and Treat model. However, Chawama First Level Hospital in Lusaka had records which showed that 32 percent of pregnant or breastfeeding women were non-adherent to combined anti-retroviral therapy (cART). Method: A mixed-method study was conducted to establish predictors of non-adherence to cART by women in the Test and Treat model of care. For the quantitative component, 92 consenting Pregnant and breastfeeding women were randomly drawn from ART defaulter register and a semi-structured questionnaire was administered. Multiple logistic regression was conducted to improve predictive power and control for confounders. Quantitative Results: The mean age was 28years. The study established that housewives were 84 percent less likely to be non-adherent [AOR 0.16;95% CI 0.12, 0.36] compared to women who were formally employed with a statistically significant P-value of 0.04. Pregnant or breastfeeding women who were several months away from home were 84.9 percent more likely to be non-adherent [AOR 15.11;95% CI 13.9, 16.4] compared to women who had travelled away from home for several days. The associated P-value was 0.03. The study also established that pregnant and breastfeeding women who were counselled in individually enclosed units were 91 percent less likely to be non-adherent compared to those who were counselled in an open space as a group [AOR 0.09;95% CI 0.02, 0.53] with an associated P-value of 0.01. Conclusion: The study established that predictors of non-adherence to cART among pregnant and breastfeeding women were: being a working-class client;being away from home or usual clinic for several months;being counselled in open spaces, and negative staff attitude. Therefore, researcher can conclusively say that predictors of non-adherence to cART can be solved by training and re-training of health workers in Patient-Centred Care Model for effective patient engagement. Women should be counselled in private rooms. Furthermore, an improvement in patient’s tracking system by the use of smart-care-cards for pregnant and breastfeeding women countrywide can reduce patient’s non-adherence to cART.
基金the National Natural Science Foundation of China(No.51075388)the Fundamental Research Funds for the Central Universities (No.2009KJ05)
文摘The non-destructive testing(NDT)of debonding in stainless steel composites plate(SSCP)is performed by infrared thermography,finite element analysis(FEA)software ANSYS is taken as the simulative tool,and 2D simulative model has been set up to investigate effect of the thickness of coating and/or substrate on the detectibility of debonging in SSCPs.Two parameters,namely the maximum defect temperature difference and defect appearing index,are defined to evaluate the detectivity of defects,and their computational methods and formulas are given respectively.The preliminary changing tendency of the maximum defect temperature difference and defect appearing index with the thickness of coating and/or substrate is found by numerical simulation.
文摘An essentially new method for non-destructive testing of elastic electrically conductive rods using non-vortex electromagnetic induction is proved theoretically. An experimental technique for defining a location of a cross crack is offered.
文摘This paper discusses the experimental results of concurrently measured Electrical and Acoustic Emissions in order to evaluate the mechanical health status of cement mortar beams subjected to three-point bending mechanical tests. In particular, the Electrical Resistance and the Electrical Current emissions are recorded concurrent with Acoustic Emissions and the experimental results are discussed under the concept of crack initiation and propagation processes. For the first time, the electrodes that are used for conducting the measurements are placed in the bulk of the specimen, near the tensile zone, during its preparation. The damage evolution is examined by monitoring the fractional change of the Electrical Resistance and the variation of the Electrical Current in combination with the Acoustic Emission recordings.
