The paper presented first results elaborated during the European Research Project Re-road which aims at the development of techniques for increasing the recycling rates of reclaimed asphalt. During service life surfac...The paper presented first results elaborated during the European Research Project Re-road which aims at the development of techniques for increasing the recycling rates of reclaimed asphalt. During service life surface asphalt courses are subjected to aging due to oxidation effects which causes the hardening of the binder and thereby a change in the chemical, physical and mechanical properties of the material. Surface courses often contain highly modified binders as well as special additives for improving the performance characteristics. As these layers inhibit the shortest service lives compared to other road construction layers every year high amounts of reclaimed surface asphalt are available for recycling. The question is raised how the reclaimed asphalt consisting of high quality and costly material components can be recycled for optimal added value. To analyze the asphalt mix service life performance and its recyclability during mix design a laboratory method was developed to simulate the real in-situ aging. First the effects of site aging on the binder and asphalt characteristics were presented. Three laboratory aging methods were discussed which aimed the accelerated aging which meets similar property changes as site aging. At last the effects of two different laboratory aging methods on the same SMA mixture were compared.展开更多
The excellent properties of SiC bring new challenges for the device packaging.In this study,the bonding strength,fracture behaviors and microstructural evolution of micron-porous Ag joint were elevated during thermal ...The excellent properties of SiC bring new challenges for the device packaging.In this study,the bonding strength,fracture behaviors and microstructural evolution of micron-porous Ag joint were elevated during thermal cycling(–50 ℃–250 ℃) in SiC/DBC(direct bonding copper) die attachment structure for different time.During harsh thermal shock test,the strength of sintered joint deceased gradually with the increase of cycling number,and the value just was half of the value of as-sintered after 1 000 cycles.Coarsening of Ag grains was observed in micron-porous joint with the structure inhomogeneity and defects increasing,which were the reasons of the strength decease.In addition,it was also found that the fracture behavior of sintered joints was changed from ductile deformation of Ag grain to brittle fracture of crack propagation after 1 000 cycles.This study will add the understanding in the mechanical properties of Ag sinter joining and its applications at high temperature.展开更多
Objective:To determine the prevalence of bacterial vaginosis(BV) in patients with vaginal discharge and evaluate the efficacy of OSOM BV blue test in diagnosis.Methods:OSOM BV blue test,a rapid diagnostic test based o...Objective:To determine the prevalence of bacterial vaginosis(BV) in patients with vaginal discharge and evaluate the efficacy of OSOM BV blue test in diagnosis.Methods:OSOM BV blue test,a rapid diagnostic test based on the principle of detection of bacterial sialidase activity in vaginal fluid specimens was conducted.A total of 405 patients in the reproductive age group(15- 45 years) having vaginal discharge were included in the study along with 10 healthy age-matched controls.Two high vaginal swabs were collected aseptically from each patient.One swab was used to make smear for gram staining,and the other was for OSOM BV blue test.Amine test and vaginal pH test were taken as well.Results:The prevalence of bacterial vaginosis was 60.7%. OSOM BV blue test showed good efficacy,as compared with gram staining in diagnosing BV.The sensitivity and specificity of OSOM BV blue test were 97.6%and 97.5%respectively.Amsel’s criteria diagnosed 180(44.4%) cases of BV and had sensitivity and specificity of 67.1%and 90.6%respectively.Thus the performance of OSOM BV blue was better than the methods based on Amsel’s criteria.Conclusions:OSOM BV blue test is an efficacious bed side test,helpful in rapidly making an accurate diagnosis of BV in setups lacking laboratory facilities or expert microbiologists.展开更多
An outdoor aging test base for geosynthetics was established in Wuhan,central China to investigate the long-term aging performance of geosynthetics. Outdoor photo-oxygen aging tests for high density polyethylene(HDPE)...An outdoor aging test base for geosynthetics was established in Wuhan,central China to investigate the long-term aging performance of geosynthetics. Outdoor photo-oxygen aging tests for high density polyethylene(HDPE) geogrid have been carried out in the base. Test results show that in the initial nine months,the tensile strength of geogrid remains unchanged or even gets larger,while the corresponding strain at break decreases slightly,exhibiting hard and brittle trend due to secondary compensatory responses to the ultraviolet(UV) aging: UV provides the required chemical crosslinking energy,resulting in the polymer crosslinking reaction. Tensile strength of the geogrid increases by about 5% in the initial nine months,but decreases after the initial nine months. The long-term research results at the test base could provide first-hand data for researching the aging properties of HDPE geogrid.展开更多
AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomography (HRCT) in patients with chronic hepatitis C virus (HCV) infection.METHODS:Thirty-four patients with c...AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomography (HRCT) in patients with chronic hepatitis C virus (HCV) infection.METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study. PFT and HRCT were performed in all cases.RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients, in forced expiratory volume in one second in 8/34 palJents, and in forced expiratory flow 25-75 in 15/34 patients, respectively. Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients. Findings of interstitial pulmonary involvement were detected in bhe HRCT of 16/34 patients. Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7, P=0.003). Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7. HRCT findings, PFT values and DLCO were not affected by KHAI in patients with HCV infection. In these patients, all the parameters were related with age.CONCLUSION: We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.展开更多
Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation ...Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two different ex situ aging processes on sulfonated poly(ether ether ketone) membranes: hydrationdehydration cycling and prolonged hydrothermal treatment. Both aged membranes exhibited enhanced phase separation under the hydrated conditions, as characterized by small angle X-ray scattering.However, when the aged membranes were dried again, the nanostructure of the membranes aged via the hydration-dehydration cycling was recoverable, whereas that of the membranes aged via prolonged hydrothermal treatment was irreversible. Furthermore, the two differently aged membranes showed clear differences in thermal, mechanical, and electrochemical properties. Finally, we implemented both aged membranes in fuel cell application. The sample aged via hydration-dehydration cycling maintained its improved cell performance, whereas the sample aged via hydrothermal treatment showed drastically reduced cell performance after durability test for 50 h.展开更多
Detrital white mica single\|crystal Ar\|Ar ages from the Himalayan foreland sedimentary record are potentially a powerful tool in constraining source regions, tectonic evolution, and the timing and extent of exhumatio...Detrital white mica single\|crystal Ar\|Ar ages from the Himalayan foreland sedimentary record are potentially a powerful tool in constraining source regions, tectonic evolution, and the timing and extent of exhumation (Copeland 1990, Najman 1997, White 1999). However such studies require large numbers of analyses, and Ar/Ar total\|fusion of white mica grains is a very rapid and cost\|effective technique.Such analyses, however, do result in the sacrifice of internal consistency checks inherent in, for example, Ar/Ar step\|heating analysis.展开更多
AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was u...AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36 mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.RESULTS: The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36 mo. The most rapid development was during the first 12 mo and the slowest development was from 30 to 36 mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24 mo. It was constant at the highest score(80) thereafter.CONCLUSION: Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children.展开更多
目的:分析计时起立-行走测试(TUGT)对老年2型糖尿病周围神经病变病人跌倒风险的评估价值。方法:回顾性分析2020年1月—2022年12月在我院内分泌科纳入治疗的2型糖尿病周围神经病变病人120例为研究对象,收集病人一般资料、TUGT测试结果,采...目的:分析计时起立-行走测试(TUGT)对老年2型糖尿病周围神经病变病人跌倒风险的评估价值。方法:回顾性分析2020年1月—2022年12月在我院内分泌科纳入治疗的2型糖尿病周围神经病变病人120例为研究对象,收集病人一般资料、TUGT测试结果,采用SPSS 22.0、R Studio 1.4.1103进行联合数据分析,研究相关性和预测价值。结果:本研究纳入的120例病人均顺利完成TUGT测试,完成率为100%,数据收集率为100%。所有病人TUGT时间为(16.03±3.29)s。Spearman相关性分析结果显示,TUGT时间与跌倒史、性别之间呈正相关(P<0.05);TUGT时间与2型糖尿病病程、合并周围神经病变病程、年龄之间无明显相关关系。TUGT时间用于预测老年2型糖尿病周围神经病变病人跌倒风险的最佳临界值为14.19 s,受试者工作特征曲线(ROC)曲线下面积(AUC)值为0.773,敏感度为86.29%,特异度为67.16%。结论:跌倒史、性别是影响老年2型糖尿病周围神经病变病人TUGT时间的危险因素,同时,TUGT时间对老年2型糖尿病周围神经病变病人跌倒具有良好的预测价值。展开更多
基金Funed by the Europeans Community’s Seventh Framework Program(FP7/2007-2013) (No. SCP-GA-2008-218747)
文摘The paper presented first results elaborated during the European Research Project Re-road which aims at the development of techniques for increasing the recycling rates of reclaimed asphalt. During service life surface asphalt courses are subjected to aging due to oxidation effects which causes the hardening of the binder and thereby a change in the chemical, physical and mechanical properties of the material. Surface courses often contain highly modified binders as well as special additives for improving the performance characteristics. As these layers inhibit the shortest service lives compared to other road construction layers every year high amounts of reclaimed surface asphalt are available for recycling. The question is raised how the reclaimed asphalt consisting of high quality and costly material components can be recycled for optimal added value. To analyze the asphalt mix service life performance and its recyclability during mix design a laboratory method was developed to simulate the real in-situ aging. First the effects of site aging on the binder and asphalt characteristics were presented. Three laboratory aging methods were discussed which aimed the accelerated aging which meets similar property changes as site aging. At last the effects of two different laboratory aging methods on the same SMA mixture were compared.
基金partly supported by the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for Scientific Research (Grant No. 19121587)supported by the Natural Science Foundation of Shaanxi Province (No.2021KW-25)。
文摘The excellent properties of SiC bring new challenges for the device packaging.In this study,the bonding strength,fracture behaviors and microstructural evolution of micron-porous Ag joint were elevated during thermal cycling(–50 ℃–250 ℃) in SiC/DBC(direct bonding copper) die attachment structure for different time.During harsh thermal shock test,the strength of sintered joint deceased gradually with the increase of cycling number,and the value just was half of the value of as-sintered after 1 000 cycles.Coarsening of Ag grains was observed in micron-porous joint with the structure inhomogeneity and defects increasing,which were the reasons of the strength decease.In addition,it was also found that the fracture behavior of sintered joints was changed from ductile deformation of Ag grain to brittle fracture of crack propagation after 1 000 cycles.This study will add the understanding in the mechanical properties of Ag sinter joining and its applications at high temperature.
文摘Objective:To determine the prevalence of bacterial vaginosis(BV) in patients with vaginal discharge and evaluate the efficacy of OSOM BV blue test in diagnosis.Methods:OSOM BV blue test,a rapid diagnostic test based on the principle of detection of bacterial sialidase activity in vaginal fluid specimens was conducted.A total of 405 patients in the reproductive age group(15- 45 years) having vaginal discharge were included in the study along with 10 healthy age-matched controls.Two high vaginal swabs were collected aseptically from each patient.One swab was used to make smear for gram staining,and the other was for OSOM BV blue test.Amine test and vaginal pH test were taken as well.Results:The prevalence of bacterial vaginosis was 60.7%. OSOM BV blue test showed good efficacy,as compared with gram staining in diagnosing BV.The sensitivity and specificity of OSOM BV blue test were 97.6%and 97.5%respectively.Amsel’s criteria diagnosed 180(44.4%) cases of BV and had sensitivity and specificity of 67.1%and 90.6%respectively.Thus the performance of OSOM BV blue was better than the methods based on Amsel’s criteria.Conclusions:OSOM BV blue test is an efficacious bed side test,helpful in rapidly making an accurate diagnosis of BV in setups lacking laboratory facilities or expert microbiologists.
基金National Key R&D Program of China(2017YFC1501201)National Natural Science Foundation of China(51709017)Fundamental Research Fund for Central Research Institute(CKSF2014060/YT,CKSF2017009/YT,CKSF2017012/YT,CKSF2017022/YT)
文摘An outdoor aging test base for geosynthetics was established in Wuhan,central China to investigate the long-term aging performance of geosynthetics. Outdoor photo-oxygen aging tests for high density polyethylene(HDPE) geogrid have been carried out in the base. Test results show that in the initial nine months,the tensile strength of geogrid remains unchanged or even gets larger,while the corresponding strain at break decreases slightly,exhibiting hard and brittle trend due to secondary compensatory responses to the ultraviolet(UV) aging: UV provides the required chemical crosslinking energy,resulting in the polymer crosslinking reaction. Tensile strength of the geogrid increases by about 5% in the initial nine months,but decreases after the initial nine months. The long-term research results at the test base could provide first-hand data for researching the aging properties of HDPE geogrid.
文摘AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomography (HRCT) in patients with chronic hepatitis C virus (HCV) infection.METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study. PFT and HRCT were performed in all cases.RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients, in forced expiratory volume in one second in 8/34 palJents, and in forced expiratory flow 25-75 in 15/34 patients, respectively. Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients. Findings of interstitial pulmonary involvement were detected in bhe HRCT of 16/34 patients. Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7, P=0.003). Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7. HRCT findings, PFT values and DLCO were not affected by KHAI in patients with HCV infection. In these patients, all the parameters were related with age.CONCLUSION: We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.
基金Byoungseok Min of Pohang Accelerator Laboratory for SAXS technical support at 4C beamline.All authors have read the manuscript and agreed to its contents。
文摘Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two different ex situ aging processes on sulfonated poly(ether ether ketone) membranes: hydrationdehydration cycling and prolonged hydrothermal treatment. Both aged membranes exhibited enhanced phase separation under the hydrated conditions, as characterized by small angle X-ray scattering.However, when the aged membranes were dried again, the nanostructure of the membranes aged via the hydration-dehydration cycling was recoverable, whereas that of the membranes aged via prolonged hydrothermal treatment was irreversible. Furthermore, the two differently aged membranes showed clear differences in thermal, mechanical, and electrochemical properties. Finally, we implemented both aged membranes in fuel cell application. The sample aged via hydration-dehydration cycling maintained its improved cell performance, whereas the sample aged via hydrothermal treatment showed drastically reduced cell performance after durability test for 50 h.
文摘Detrital white mica single\|crystal Ar\|Ar ages from the Himalayan foreland sedimentary record are potentially a powerful tool in constraining source regions, tectonic evolution, and the timing and extent of exhumation (Copeland 1990, Najman 1997, White 1999). However such studies require large numbers of analyses, and Ar/Ar total\|fusion of white mica grains is a very rapid and cost\|effective technique.Such analyses, however, do result in the sacrifice of internal consistency checks inherent in, for example, Ar/Ar step\|heating analysis.
文摘AIM: To determine age norms in the first three years of life for grating visual acuity and contrast sensitivity obtained with Lea grating test and Hiding Heidi low contrast face test. METHODS: Lea grating test was used to estimate binocular grating acuity and Hiding Heidi low contrast face test was used to estimate contrast sensitivity in 600 healthy infants and children. Age ranged from 3 to 36 mo subdivided into 12 groups subjected for full ophthalmologic and pediatric examinations.RESULTS: The grating acuity developed along the first three years of life. It ranged from 1.88±0.32 c/d at 3mo to 30.95±0.77 c/d at 36 mo. The most rapid development was during the first 12 mo and the slowest development was from 30 to 36 mo. The contrast sensitivity showed rapid development in the first two years of life. Its mean value ranged from 4.23±1.17 at 3mo to 78.26±8.21 at 24 mo. It was constant at the highest score(80) thereafter.CONCLUSION: Age norms for grating acuity along with contrast sensitivity offer a more comprehensive measure of spatial vision and should be incorporated in clinical practice for better visual assessment in preverbal and nonverbal children.
文摘目的:分析计时起立-行走测试(TUGT)对老年2型糖尿病周围神经病变病人跌倒风险的评估价值。方法:回顾性分析2020年1月—2022年12月在我院内分泌科纳入治疗的2型糖尿病周围神经病变病人120例为研究对象,收集病人一般资料、TUGT测试结果,采用SPSS 22.0、R Studio 1.4.1103进行联合数据分析,研究相关性和预测价值。结果:本研究纳入的120例病人均顺利完成TUGT测试,完成率为100%,数据收集率为100%。所有病人TUGT时间为(16.03±3.29)s。Spearman相关性分析结果显示,TUGT时间与跌倒史、性别之间呈正相关(P<0.05);TUGT时间与2型糖尿病病程、合并周围神经病变病程、年龄之间无明显相关关系。TUGT时间用于预测老年2型糖尿病周围神经病变病人跌倒风险的最佳临界值为14.19 s,受试者工作特征曲线(ROC)曲线下面积(AUC)值为0.773,敏感度为86.29%,特异度为67.16%。结论:跌倒史、性别是影响老年2型糖尿病周围神经病变病人TUGT时间的危险因素,同时,TUGT时间对老年2型糖尿病周围神经病变病人跌倒具有良好的预测价值。