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The Importance of Molecular and Clinical Laboratory Tests in Diagnosis and Treatment of Coronavirus Disease 被引量:2
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作者 Majid Rezaei Basiri Ghazi-Khansari,M. +1 位作者 Sahhaf-Ebrahimi,F Alilou,S. 《Journal of Pharmacy and Pharmacology》 CAS 2021年第6期232-238,共7页
900 abusers were tested for the presence of drug abuse and coronavirus disease.In the early stage,the throat and noise samples of these patients were examined by polymerase chain reaction(PCR).The mean age of the stud... 900 abusers were tested for the presence of drug abuse and coronavirus disease.In the early stage,the throat and noise samples of these patients were examined by polymerase chain reaction(PCR).The mean age of the study group is 42±23.Hematological and serological examinations were performed on 131 patients.All data were analyzed by t-test and one-way analysis of variance(ANOVA).Therefore,P<0.05 is considered as the significance of the test results.The results showed that 131 patients in the study group had positive results of PCR tests and nearby they had Covid-19.Approximately 90%of patients with coronavirus disease showed positive serological tests and lymphopenic condition.All of urine or blood samples in the 131 patients were positive for the presence of abuse drugs.C-reactive protein(CRP)is one of important serologic test that detected on these patients.This study showed the importance of molecular genetics test such as PCR and also hematology and serology tests in distinguish of coronavirus diseases. 展开更多
关键词 Abusers coronavirus disease clinical laboratory tests SAMPLES treatment.
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Evaluation of Abuse Drugs and Clinical Laboratory Tests Variations in Whole Blood & Urine Samples of Abusers 被引量:1
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作者 Majid Rezaei Basiri Mojgan Behshid +9 位作者 Alireza Najafi Saleh Alilou Haniyeh Mohebbi-Kamali: Fatemeh Hosseindoust Marziyeh Mokhtari Valiyollah Watani Ladan Aminzadeh Fatemeh Seyed Nejad Ashraf Razavi Ligha Saadat 《Journal of Pharmacy and Pharmacology》 2018年第1期69-76,共8页
In this study, five hundred urine samples and five hundred blood samples of abusers were examined for the presence of alkaloid substances and abuse drugs in urines and bloods. These numbers of blood and urine samples ... In this study, five hundred urine samples and five hundred blood samples of abusers were examined for the presence of alkaloid substances and abuse drugs in urines and bloods. These numbers of blood and urine samples of addicts in clinics of welfare organization, during detoxification treatment or maintenance treatment were screened for abuse drugs presence. The all of samples were tested through as a view of clinical laboratory methods. Age ranges of female patients were 35 ~ 15 and age range of males patients were 45 ~ 15. All patients filled questionnaire and satisfy forms too. First, all fresh urine and blood samples were examined to confirm presence drugs abuses, depend on their addiction and treatment, so all samples were confirmed by two tests. Then they were examined to other clinical laboratory tests. All data were analyzed by t-test and were Anova one way and two ways of Anova Turkey, and p 〈 0.05 was considered significant. The p-value of this study was p = 0.0001. The results of this study were showed that 4% of abusers had mild increase in hematocrite level and 2% of narcotic drugs abusers had mild lower level of blood sugars than normal range and 4% of participants had increase liver enzymes such ALT (alanine transferase), AST (aspartat transferase), ALP (alkaline phosphatease) and 1% of them had renal failure. Although blood level BUN (blood urea nitrogen) and creatinin were examined to evaluation of their renal failure .The results in Tabriz/Iran undrevision of welfare organization clinics were approximately showed that positive results of addiction are in each of urine and blood samples. Because some of abusers directly consumed full long time agonist or partial agonists' drugs such as methadone and buprenorphine for their maintenance therapy in clinics. Also doing test on blood samples has high importance in distinguishing and confirmation of drugs abuse in samples. Also in this study we conclude that among all drug analytical methods the cheapest and easiest test to screening opioids and other abuse drugs in urine and blood samples is strip test for rapid diagnosis, also tests on blood samples have high importance as a view point of accuracy to distinguishing of drugs abuse, and serum levels of some other parameters showed all abusers patients situation such as liver and renal dysfimction through clinical laboratory tests. 展开更多
关键词 Abusers urine and whole blood samples strip test thin-layer chromatography abuse drugs clinical laboratory tests.
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Alterations in the Results of Biochemical Laboratory Tests Due to the Administration of Antihypertensive Drugs
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作者 Cleiton Fantin Patrícia Dabila Moraes Aparecido +2 位作者 Pedro Kazuya de Arruda Takano Thairineda Silva Jucá Luciana dos Santos Viana 《Journal of Pharmacy and Pharmacology》 CAS 2022年第4期132-139,共8页
Objective:Perform a literary review of the interference in the results of biochemical laboratory tests caused by antihypertensive drugs.Methods:This is a review of the scientific literature with descriptive research p... Objective:Perform a literary review of the interference in the results of biochemical laboratory tests caused by antihypertensive drugs.Methods:This is a review of the scientific literature with descriptive research performed according to the PRISMA model using the databases PUBMED,SCIELO,MEDLINE,LILACS,and searches of Brazilian Ministry of Health and Federal Pharmacy Council publications,reagent kits and package inserts approved by ANVISA.Literature and papers in Portuguese and English were selected,prioritizing the years 2010 to 2020.Results:The diuretic class of antihypertensive drugs causes decreases glucose tolerance,thus resulting in an increase in triglycerides.In long-term use,the drug captopril can increase serum levels of potassium,creatine kinase and decreases blood sodium.Methyldopa causes an increase in AST levels.Propranolol is associated with an increase in triglyceride levels and a decrease in HDL and glucose levels.The constant use of losartan results in an increase in HDL,a decrease in uric acid levels and a slight and transient increase in transaminases.In the Gold Analisa,Bioclin and Labtest reagent kits,most of the alterations occur due to the increase in levels of serum biomarkers according to the class of the antihypertensive drug.Conclusions:Biochemical alterations in serum can result in false-positive or false-negative reports,since it can be observed that most of the dosages caused increases due to the physiological effect of the drugs.The antihypertensive drugs that showed the highest incidence of interference were captopril,atenolol,losartan and propranolol. 展开更多
关键词 ANTIHYPERTENSIVES CAPTOPRIL biochemical markers LOSARTAN PROPRANOLOL diagnosis and laboratory tests
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Compaction and seepage characteristics of broken coal and rock masses in coal mining:A review in laboratory tests
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作者 Cun Zhang Yanhong Chen +1 位作者 Zhaopeng Ren Fangtian Wang 《Rock Mechanics Bulletin》 2024年第2期1-20,共20页
Broken coal and rock(BCR)are an important component medium of the caving zone in the goaf(or gob),as well as the main filling material of fault fracture zone and collapse column.The compaction seepage characteristics ... Broken coal and rock(BCR)are an important component medium of the caving zone in the goaf(or gob),as well as the main filling material of fault fracture zone and collapse column.The compaction seepage characteristics of BCR directly affect the safe and efficient mining of coal mines.Thus,numerous laboratory studies have focused on the compaction seepage characteristics of BCR.This paper first outlines the engineering problems involved in the BCR during coal mining including the air leakage,the spontaneous combustion,the gas drainage,and the un-derground reservoirs in the goaf.Water inrush related to tectonics such as faults and collapse columns and surface subsidence related to coal gangue filling and mining also involve the compaction seepage characteristics of BCR.Based on the field problems of BCR,many attempts have been made to mimic field environments in laboratory tests.The experimental equipment(cavity size and shape,acoustic emission,CT,etc.)and experimental design for the BCR were firstly reviewed.The main objects of laboratory analysis can be divided into compression tests and seepage test.During the compaction test,the main research focuses on the bearing deformation characteristics(stress-strain curve),pore evolution characteristics,and re-crushing characteristics of BCR.The seepage test mainly uses gas or water as the main medium to study the evolution characteristics of permeability under different compaction stress conditions.In the laboratory tests,factors such as the type of coal and rock mass,particle size,particle shape,water pressure,temperature,and stress path are usually considered.The lateral compression test of BCR can be divided into three stages,including the self-adjustment stage,the broken stage,and the elastic stage or stable stage.At each stage,stress,deformation,porosity,energy,particle size and breakage rate all have their own characteristics.Seepage test regarding the water permeability experiment of BCR is actually belong to variable mass seepage.While the experimental test still focuses on the influence of stress on the pore structure of BCR in terms of gas permeability.Finally,future laboratory tests focus on the BCR related coal mining including scaling up,long term loading and water immersion,mining stress path matching were discussed. 展开更多
关键词 Coal mining Broken coal and rock laboratory test Engineering problems Experimental equipment Breakage characteristics Compaction characteristics Seepage characteristics
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From bed to bench: Which attitude towards the laboratoryliver tests should health care practitioners strike?
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作者 Giovanni Tarantino 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第37期4917-4923,共7页
There is a general consensus in re-interpreting the so-called liver function tests in the light of novel discoveries. At the same time, recent evidence favours the use of different laboratory data to assess liver dama... There is a general consensus in re-interpreting the so-called liver function tests in the light of novel discoveries. At the same time, recent evidence favours the use of different laboratory data to assess liver damage, fibrosis or regenerative process, but this point is not always shared. Actually, balancing the need for diagnosis, prognostic evaluation and therapy response of liver disease with a good cost/benefit ratio is very difficult. New tests are probably not needed but the aim should be for better utilization of existing tests to contain the increasing cost of health care. 展开更多
关键词 laboratory liver tests ALanine aminotransferase Aspartate aminotransferase Quantitative testing of liver function Alcoholic liver disease Non-alcoholicsteatohepatitis Hepatitis C virus
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Subjective Evaluation of Clothing Comfort and Their Correlation with Laboratory Test 被引量:1
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作者 刘丽英 张渭源 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期75-78,共4页
A series of polyester, cotton, and polyester/cotton blend fabrics were evaluated in a subjective wear. Subjective trial data were correlated with the results of in-house laboratory tests with the regression methods. E... A series of polyester, cotton, and polyester/cotton blend fabrics were evaluated in a subjective wear. Subjective trial data were correlated with the results of in-house laboratory tests with the regression methods. Experimental results indicate that clothing-comfort assessment by human perception provides a sound basis for comparison of apparel garments under combined microclimates and human-activity levels of 展开更多
关键词 subjective wear in-house laboratory tests regression methods clothing-comfort assessment human perception
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Engineering behaviors of reinforced gabion retaining wall based on laboratory test 被引量:1
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作者 林宇亮 杨果林 +1 位作者 李昀 赵炼恒 《Journal of Central South University》 SCIE EI CAS 2010年第6期1351-1356,共6页
In order to study the engineering behaviors of reinforced gabion retaining wall,laboratory model test was carried out.Cyclic load and unload of five levels(0-50,0-100,0-50,0-200 and 0-250 kPa) were imposed.Vertical ea... In order to study the engineering behaviors of reinforced gabion retaining wall,laboratory model test was carried out.Cyclic load and unload of five levels(0-50,0-100,0-50,0-200 and 0-250 kPa) were imposed.Vertical earth pressure,lateral earth pressure,deformation behaviors of reinforcements,potential failure surface and deformation behaviors of wall face were studied.Results show that vertical earth pressure is less than theoretical value,the ratio of vertical earth pressure to theoretical value increases nearly linearly with increasing load,and the correlation coefficient of regression equation is 0.92 for the second layer and 0.79 for the fifth layer.The distribution of lateral earth pressure along the wall back is nonlinear and it is less than theoretical value especially when the load imposed at the top of retaining wall is large.Therefore,reinforced gabion retaining wall will be in great safety when current method is adopted.The deformation behaviors of reinforcements both in the third layer and the fifth layer are single-peak distributions,and the position of the maximum strain is behind that determined by 0.3H(Here H refers to the height of retaining wall) method or Rankine theory.Lateral deformation of wall face increases with increasing load,and the largest lateral deformation occurs in the fourth layer,which lead to a bulging in the middle of wall face. 展开更多
关键词 reinforced gabion earth pressure DEFORMATION laboratory test
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Laboratory Test on Volumetric Characteristics of Saturated Sea Sand Under Cyclic Loading 被引量:1
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作者 刘汉龙 周云东 高玉峰 《海洋工程:英文版》 2003年第1期93-100,共8页
The deformation of sea coast or sandy deposits caused by earthquakes can lead to catastrophic damages to various port structures. The volumetric deformation is mainly induced by densification of sand during the dissip... The deformation of sea coast or sandy deposits caused by earthquakes can lead to catastrophic damages to various port structures. The volumetric deformation is mainly induced by densification of sand during the dissipation of excess pore water pressure created by cyclic loading. Based on laboratory test, the reconsolidation volumetric characteristics of saturated sea sand are investigated. The experiments are conducted with a newly developed multi functional triaxial test equipment. Two types of dynamic loads are applied to the samples to clarify different kinds of affecting factors. It is found that the reconsolidation volumetric strain is correlated not only to the excess pore water pressure and the maximum shear strain during the dynamic loading, but also to the effective confining pressure. A new formula is put forward to calculate the volumetric strain during reconssolidation. 展开更多
关键词 SAND laboratory test RECONSOLIDATION volumetric strain confining pressure
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Clinical Diagnosis and Treatment Characteristics of Acute Respiratory Infections in Children and New Developments in Laboratory Testing 被引量:2
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作者 Yueliao Ma Lingyu Lu Qiangcai Mai 《Open Journal of Pediatrics》 2021年第1期114-124,共11页
Acute respiratory tract infection</span><span style="font-family:""><span style="font-family:Verdana;"> (ARTI) in children is the most common infectious disease in childhood,... Acute respiratory tract infection</span><span style="font-family:""><span style="font-family:Verdana;"> (ARTI) in children is the most common infectious disease in childhood, and its pathogens include viruses, bacteria and fungi, mycoplasma, chlamydia and rickettsia. In recent years, with the continuous development of pathogen detection methods, the diagnosis and treatment of acute respiratory infections has received more and more clinical attention. The clinical diagnosis and treatment characteristics of acute respira</span><span style="font-family:Verdana;">tory infections in children and the research of clinical laboratory detection </span><span style="font-family:Verdana;">methods have also been continuously developed. The author collected refer</span><span style="font-family:Verdana;">ences to review the clinical features and new developments in laboratory</span><span style="font-family:Verdana;"> testing of acute respiratory tract infection in children. 展开更多
关键词 CHILDREN Respiratory Tract Infections PATHOGENS laboratory Testing ACUTE
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A laboratory study of stress arching around an inclusion due to pore pressure changes
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作者 Hani Asaei Mahdi Moosavi Mohammad Ali Aghighi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第4期678-693,共16页
When the pore pressure in a porous rock changes, stress arching will occur within the rock and the surrounding region. Stress arching ratio is defined as the total stress changes in the porous rock to the pore pressur... When the pore pressure in a porous rock changes, stress arching will occur within the rock and the surrounding region. Stress arching ratio is defined as the total stress changes in the porous rock to the pore pressure change in the region. The region may have the same or different elastic moduli with the surrounding rock, which is usually referred to as inclusion or inhomogeneity. Stress arching is responsible for many geomechanical problems encountered during production or injection; in addition, it is a crucial parameter in stress estimation during field development. This paper aims to present laboratory measurements of vertical stress arching ratio in a material surrounding the inclusion(inhomogeneity).To the authors’ knowledge, few laboratory experiments have been reported on direct measurement of stress arching. The inclusion is a cylindrical sandstone(44 mm in diameter and 50 mm in height)embedded in a larger cylindrical sandstone(150 mm in diameter and 154 mm in height), both of which are made synthetically. These two parts are separated and sealed by a internal polyurethane sleeve.Vertical stress changes are recorded by a mini hydraulic sensor embedded in surrounding rock. Laboratory results are compared to those obtained by numerical models. These models are checked with analytical formulations. The results of numerical models show a good agreement with laboratory data.The numerical results also indicate that the sensor response is affected by elastic properties of the internal sleeve. According to the sensitivity analysis performed, in the absence of the internal sleeve,properties of the inclusion have significant effects on the surrounding stress arching induced. 展开更多
关键词 Stress arching laboratory test Large-scale sample Synthetic sandstone
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Analysis of laboratory and imaging examination results of patients with COVID-192 years after discharge in Chengdu
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作者 Zhao Ben-Nan Du Qing +4 位作者 Kang Jun Liu Da-feng Zhang Ling Lan Li-juan Yuan Yuan 《Journal of Hainan Medical University》 2022年第17期1-7,共7页
Objective:To summarize the follow-up results of laboratory examination,echocardiographic and chest CT of patients with COVID-19 at the time of 2 years after discharge in Chengdu.Methods:A total of 29 COVID-19 survivor... Objective:To summarize the follow-up results of laboratory examination,echocardiographic and chest CT of patients with COVID-19 at the time of 2 years after discharge in Chengdu.Methods:A total of 29 COVID-19 survivors who have participated in the 1-year follow-up and 2-year follow-up at Public Health Clinical Center of Chengdu were included in our study.Their blood laboratory tests,echocardiography and chest CT results were analyzed in order to evaluate the long-term recovery of COVID-19 survivors.Results:The most common abnormal laboratory test results at the 2-year follow-up were increased serum fibronectin(21 cases,72.4%)and decreased NK cell counts(19 cases,65.5%).Compared with laboratory test results at the 1-year follow-up,platelet count,hydroxybutyrate dehydrogenase and creatine kinase isoenzyme were decreased(all P<0.05),while serum fibrinogen,triglyceride,insulin and non-specific immunoglobulin A were increased(all P<0.05).Serum specific total SARS-CoV-2 antibody amount in COVID-19 survivors at half a year after COVID-19 vaccine was significantly higher than that before vaccination.More than half of patients(55.2%)had normal echocardiography results at the 2-year follow-up,the main abnormal results of them were valve regurgitation(7 cases,24.1%)and reduced left ventricular diastolic function(9 cases,31.0%).Compared with 1-year follow-up,7 patients had fewer abnormal cardiac ultrasound results.28 cases underwent chest CT at the 2-year follow-up,the mainly abnormal results were ground glass shadow(17.9%),pulmonary nodules(diameter<6mm)(32.1%)and scattered cable shadow(39.3%).71.4%(20/28)of them had no significant change between the two chest CT results.Conclusion:The mainly abnormal blood laboratory indicators in COVID-19 survivors at 2-year follow-up after discharge were increased serum fibronectin and decreased NK cell counts.Although echocardiography and chest CT results were no significant change between 1-year follow-up and 2-year follow-up among COVID-19 survivors,there were still some patients whose abnormal results were decreasing.Serum specific total SARS-CoV-2 antibody amount in COVID-19 survivors at half a year after COVID-19 vaccine was still significantly higher than that before vaccination,but the amount of specific antibody had a downward trend with time. 展开更多
关键词 COVID-19 SARS-CoV-2 FOLLOW-UP laboratory test VACCINATION
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New Progress in Clinical Diagnosis, Treatment and Laboratory Testing of Acute Respiratory Infections in Children
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作者 Huan Zhao Xiaoyu Jiang +1 位作者 Lingyu Lu Qing Lin 《American Journal of Molecular Biology》 2022年第1期1-9,共9页
Acute respiratory infection in children (ARTI) is the most common childhood infectious disease, and its pathogens include bacteria, fungi, viruses, chlamydia, mycoplasma and rickettsia. In recent years, with the conti... Acute respiratory infection in children (ARTI) is the most common childhood infectious disease, and its pathogens include bacteria, fungi, viruses, chlamydia, mycoplasma and rickettsia. In recent years, with the continuous development of pathogen detection methods, the diagnosis and treatment of acute respiratory infections has received more and more attention from clinicians. The clinical diagnosis and treatment of acute respiratory infections in children and the research of laboratory detection methods have also been continuously developed. The manuscript presents a review of progress in the clinical diagnosis, treatment and laboratory testing of acute respiratory infections in children by collecting references. 展开更多
关键词 CHILDREN Respiratory Infections PATHOGENS laboratory Testing ACUTE
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Statistical analysis of physico-mechanical parameters of sandstones occurring in orogenic settings
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作者 PAPPALARDO Giovanna CARBONE Serafina +2 位作者 MONACO Carmelo ZOCCO Giordana MINEO Simone 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1388-1402,共15页
In northeastern Sicily(Italy),sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic belt.Despite being part of the same geological formation,these sandstones are c... In northeastern Sicily(Italy),sandstone rock masses widely crop out as cover deposits over crystalline terrains belonging to the orogenic belt.Despite being part of the same geological formation,these sandstones are characterized by highly different features in terms of texture and physico-mechanical properties.This poses a scientific question on the possibility of tracing these rocks to a single statistical model,which could be representative of their main engineering geological properties.Therefore,it is worth investigating on the possible reasons of such differences,that should be searched either in the current geographical sandstone distribution or in the rock texture.For this study,sandstone samples were collected from different sites and were analyzed at both the hand and thin section scales.Three sandstone types were recognized,characterized by a different texture.Then,the laboratory characterization allowed estimating their main physico-mechanical and ultrasonic properties,such as porosity,density,mechanical strength,deformability,and ultrasonic velocities.The rock mechanical strength proved linked to the rock compactness and to the presence of lithic fragments,while pores and a pseudo-matrix between grains represent weakening features.Rock data were also statistically analyzed by grouping the specimens according to a geographical criterion,with respect to their sampling area,but no link was found between location and rock properties.Finally,with the aim of achieving mathematical laws that could be used to predict some rock properties from others,useful for practical purposes when dealing with such a high property variability,single and multiple regression analyses were carried out.Results show that the Uniaxial Compressive Strength,porosity,and P-wave velocity are the best predictors for a quick,indirect estimation of the main physico-mechanical parameters.The methodological approach developed for this research can be taken as reference to study other worldwide cases,involving rocks characterized by a wide range of physico-mechanical properties and covering large regional territories. 展开更多
关键词 SANDSTONE laboratory test Uniaxial Compressive Strength POROSITY ROCKS
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Discussion of“Site observations of weathered granitic soils subjected to cementation and partial drainage using SCPTU”[J Rock Mech Geotech Eng 15(2023)984-996]
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作者 Fernando Artur Brasil Danziger Graziella Maria Faquim Jannuzzi +1 位作者 Harley Alves da Mata Bacelar Arthur Veiga Silverio Pinheiro 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4330-4333,共4页
Comprehensive data from in situ and laboratory tests in residual soil have been presented by Zhang et al.(2023).A number of issues addressed in the paper have been the interest of the discussers,namely the characteris... Comprehensive data from in situ and laboratory tests in residual soil have been presented by Zhang et al.(2023).A number of issues addressed in the paper have been the interest of the discussers,namely the characterisation and behaviour of residual soils,limitation of piezocone testing due to the capacity of the entire system,measurement of shear wave velocity,rate effect of piezocone(CPTU)testing and piezocone testing with dual pore pressure penetrometers.Clarification and complementation of these issues are required with regard to both the execution and interpretation of the tests. 展开更多
关键词 Residual soil Seismic piezocone test laboratory test Soil classification Pore pressure measurement Rate effect
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Protective effect of retaining wall on rock avalanche:A case study of Nayong rock avalanche in China
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作者 WANG Zhongfu SHI Fengge +3 位作者 HE Siming ZHANG Xusheng WANG Jingying LIU Enlong 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1215-1230,共16页
Rock avalanches are generally difficult to prevent and control due to their high velocities and the extensive destruction they cause.However,barrier structures constructed along the path of a rock avalanche can partia... Rock avalanches are generally difficult to prevent and control due to their high velocities and the extensive destruction they cause.However,barrier structures constructed along the path of a rock avalanche can partially mitigate the magnitudes and consequences of such catastrophic events.We selected a rock avalanche in Nayong County,Guizhou Province,China as a case to study the effect of the location and height of a retaining wall on the dynamic characteristics of rock avalanche by using both actual terrain-based laboratory-model tests and coupled PFC3D-FLAC3D numerical simulations.Our findings demonstrate that a retaining wall can largely block a rock avalanche and its protective efficacy is significantly influenced by the integrity of the retaining wall.Coupled numerical simulation can serve as a powerful tool for analyzing the interaction between a rock avalanche and a retaining wall,facilitating precise observations of its deformation and destruction.The impact-curve characteristics of the retaining wall depend upon whether or not the rock avalanche-induced destruction is taken into account.The location of the retaining wall exerts a greater influence on the outcome compared to the height and materials of the retaining wall,while implementing a stepped retaining-wall pattern in accordance with the terrain demonstrates optimal efficacy in controlling rock avalanche. 展开更多
关键词 Rock avalanche laboratory model test Retaining wall PFC^(3D) FLAC^(3D) Impact force
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Low frequency vibration tests on a floating slab track in an underground laboratory 被引量:5
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作者 De-yun DING Wei-ning LIU +2 位作者 Ke-fei LI Xiao-jing SUN Wei-feng LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第5期345-359,共15页
Low frequency vibrations induced by underground railways have attracted increasing attention in recent years. To obtain the characteristics of low frequency vibrations and the low frequency performance of a floating s... Low frequency vibrations induced by underground railways have attracted increasing attention in recent years. To obtain the characteristics of low frequency vibrations and the low frequency performance of a floating slab track (FST), low frequency vibration tests on an FST in an underground laboratory at Beijing Jiaotong University were carried out. The FST and an unbalanced shaker SBZ30 for dynamic simulation were designed for use in low frequency vibration experiments. Vibration measurements were performed on the bogie of the unbalanced shaker, the rail, the slab, the tunnel invert, the tunnel wall, the tunnel apex, and on the ground surface at distances varying from 0 to 80 m from the track. Measurements were also made on several floors of an adjacent building. Detailed results of low frequency vibration tests were reported. The attenuation of low frequency vibrations with the distance from the track was presented, as well as the responses of different floors of the building. The experimental results could be regarded as a reference for developing methods to control low frequency vibrations and for adopting countermeasures. 展开更多
关键词 Low frequency vibrations laboratory tests Floating slab track (FST) Vibration isolation efficiency
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A male-ABCD algorithm for hepatocellular carcinoma risk prediction in HBs Ag carriers 被引量:3
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作者 Yuting Wang Minjie Wang +23 位作者 He Li Kun Chen Hongmei Zeng Xinyu Bi Zheng Zhu Yuchen Jiao Yong Wang Jian Zhu Hui Zhao Xiang Liu Chunyun Dai Chunsun Fan Can Zhao Deyin Guo Hong Zhao Jianguo Zhou Dongmei Wang Zhiyuan Wu Xinming Zhao Wei Cui Xuehong Zhang Jianqiang Cai Wanqing Chen Chunfeng Qu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第3期352-363,共12页
Objective: Hepatocellular carcinoma(HCC) development among hepatitis B surface antigen(HBs Ag) carriers shows gender disparity, influenced by underlying liver diseases that display variations in laboratory tests. We a... Objective: Hepatocellular carcinoma(HCC) development among hepatitis B surface antigen(HBs Ag) carriers shows gender disparity, influenced by underlying liver diseases that display variations in laboratory tests. We aimed to construct a risk-stratified HCC prediction model for HBs Ag-positive male adults.Methods: HBs Ag-positive males of 35-69 years old(N=6,153) were included from a multi-center populationbased liver cancer screening study. Randomly, three centers were set as training, the other three centers as validation. Within 2 years since initiation, we administrated at least two rounds of HCC screening using Bultrasonography and α-fetoprotein(AFP). We used logistic regression models to determine potential risk factors,built and examined the operating characteristics of a point-based algorithm for HCC risk prediction.Results: With 2 years of follow-up, 302 HCC cases were diagnosed. A male-ABCD algorithm was constructed including participant's age, blood levels of GGT(γ-glutamyl-transpeptidase), counts of platelets, white cells,concentration of DCP(des-γ-carboxy-prothrombin) and AFP, with scores ranging from 0 to 18.3. The area under receiver operating characteristic was 0.91(0.90-0.93), larger than existing models. At 1.5 points of risk score,26.10% of the participants in training cohort and 14.94% in validation cohort were recognized at low risk, with sensitivity of identifying HCC remained 100%. At 2.5 points, 46.51% of the participants in training cohort and 33.68% in validation cohort were recognized at low risk with 99.06% and 97.78% of sensitivity, respectively. At 4.5 points, only 20.86% of participants in training cohort and 23.73% in validation cohort were recognized at high risk,with positive prediction value of 22.85% and 12.35%, respectively.Conclusions: Male-ABCD algorithm identified individual's risk for HCC occurrence within short term for their HCC precision surveillance. 展开更多
关键词 Hepatocellular carcinoma asymptotic HBs Ag carriers risk prediction model SCREENING laboratory tests
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Calibration Method of Capacitive Soil Moisture Sensor 被引量:3
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作者 XIAO Lei JI Tianjian ZHANG Qingsong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期109-114,共6页
Soil properties and water content vary from place to place. The calibration method based on capacitive soil moisture and humidity sensor is carried out. The sensor readings are compared with the mass water content mea... Soil properties and water content vary from place to place. The calibration method based on capacitive soil moisture and humidity sensor is carried out. The sensor readings are compared with the mass water content measured by the oven dried method,and the calibration formula of sensor reading and mass moisture content is established.Results show that the sensor reading has a good linear relationship with the mass water content measured by the oven dried method,and has high precision. It can calibrate the mass moisture content of the data obtained from the moisture migration test in the soil column. 展开更多
关键词 capacitive soil moisture sensor mass moisture content CALIBRATION laboratory tests
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Evaluation of soil fabric using elastic waves during load-unload 被引量:1
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作者 Yang Li Masahide Otsubo Reiko Kuwano 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2687-2700,共14页
It is essential to assess the evolution of soil fabric as it has an important role in the mechanical responses of soils during complex loading conditions.This contribution carries out the physical experiments using th... It is essential to assess the evolution of soil fabric as it has an important role in the mechanical responses of soils during complex loading conditions.This contribution carries out the physical experiments using three granular materials in the laboratory.The variations of compression and shear wave velocities(Vp and Vs)are investigated during load-unload cycles under dry and drained conditions.Supplementary discrete element method(DEM)simulations are performed to understand the evolution of soil fabric during the equivalent load-unload cycles using spherical particles.Vp and Vs are not always reversible even though the stress state regains its isotropic condition after unload,indicating that Vp and Vs are governed by not only the stress state but also the fabric change.The variations of Vp/Vs are density-and stress-dependent;a higher level of stress ratio(s01/s03)threshold is observed for denser packings to trigger a significant change in wave velocity ratio(Vp/Vs)for experimental results using spherical glass beads and simulation data using spherical particles.Considering the particle shape,a higher s01/s03 threshold is found for more angular particles than rounded particles.The DEM result reveals that Vp/Vs of spherical particles can be correlated linearly with the evolution of fabric ratio(Fver/Fhor)during loadunload in a pre-peak range under dry and drained conditions. 展开更多
关键词 Soil fabric ANISOTROPY Elastic waves Discrete element modelling laboratory tests
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Strength and dilatancy behaviors of deep sands in Shanghai with a focus on grain size and shape effect 被引量:1
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作者 Bandana Tiwaria Guanlin Ye +2 位作者 Mingguang Li Usama Khalid Santosh Kumar Yadav 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第6期1214-1225,共12页
With rapid development of infrastructures like tunnels and open excavations in Shanghai,investigations on deeper soils have become critically important.Most of the existing laboratory works were focused on the clayey ... With rapid development of infrastructures like tunnels and open excavations in Shanghai,investigations on deeper soils have become critically important.Most of the existing laboratory works were focused on the clayey strata up to Layer 6 in Shanghai,i.e.at depth of up to 40 m.In this paper,Layers 7,9,and 11,which were mostly formed of sandy soils at depth of up to 150 m,were experimentally investigated with respect to physico-mechanical behaviors.The stressestrain behaviors were analyzed by the consolidated drained/undrained(CD/CU)triaxial tests under monotonic loading.One-dimensional(1D)oedometer tests were performed to investigate the consolidation properties of the sandy soils.Specimens were prepared at three different relative densities for each layer.Also,the micro-images and particle size analyzers were used to analyze the shape and size of the sand grains.The influences of grain size,density,and angularity on the stressestrain behaviors and compressibility were also studied.Compared to the other layers,Layer 11 had the smallest mean grain size(D50),highest compressibility,and lowest shear strength.In contrast,Layer 9 had the largest mean grain size,lowest compressibility,and highest shear strength.Layer 7 was of intermediate mean grain size,exhibiting more compressibility and less shear strength than that of Layer 9.Also,the critical state parameters and maximum dilatancy rate of different layers were discussed. 展开更多
关键词 Deep sands in Shanghai laboratory tests Shear strength DILATANCY Relative density
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