Vertical drains are used to accelerate consolidation of clays in ground improvement projects.Smear zones exist around these drains,where permeability is reduced due to soil disturbance caused by the installation proce...Vertical drains are used to accelerate consolidation of clays in ground improvement projects.Smear zones exist around these drains,where permeability is reduced due to soil disturbance caused by the installation process.Hansbo solution is widely used in practice to consider the effects of drain discharge capacity and smear on the consolidation process.In this study,a computationally efficient diameter reduction method(DRM)obtained from the Hansbo solution is proposed to consider the smear effect without the need to model the smear zone physically.Validated by analytical and numerical results,a diameter reduction factor is analytically derived to reduce the diameter of the drain,while achieving similar solutions of pore pressure dissipation profile as the classical full model of the smear zone and drain.With the DRM,the excess pore pressure u obtained from the reduced drain in the original un-disturbed soil zone is accurate enough for practical applications in numerical models.Such performance of DRM is independent of soil material property.Results also show equally accurate performance of DRM under conditions of multi-layered soils and coupled radial-vertical groundwater flow.展开更多
Blood smear test is the basic method of blood cytology and is also a standard medical test that can help diagnose various conditions and diseases.Morphological examination is the gold stan-dard to determine pathologic...Blood smear test is the basic method of blood cytology and is also a standard medical test that can help diagnose various conditions and diseases.Morphological examination is the gold stan-dard to determine pathological changes in blood cell morphology.In the biology and medicine automation trend,blood smears'automated management and analysis is very necessary.An online blood smear automatic microscopic image detection system has been constructed.It includes an online blood smear automatic producing part and a blood smear automatic micro-scopic image detection part.Online identity authentication is at the core of the system.The identifiers printed online always present dot matrix digit code(DMDC)whose stroke is not continuous.Considering the particularities of DMDC and the complexities of online application environment,an online identity authentication method for blood smear with heterological theory is proposed.By synthesizing the certain regional features according to the heterological theory,high identification accuracy and high speed have been guaranteed with few features required.In the experiment,the suficient correct matches bet ween the tube barcode and the identification result verified its feasibility and validity.展开更多
Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected...Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.展开更多
Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide sc...Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.展开更多
Damage smear method(DSM)is adopted to study trans-scale progressive rock failure process,based on statistical meso-damage model and finite element solver.The statistical approach is utilized to reflect the mesoscopic ...Damage smear method(DSM)is adopted to study trans-scale progressive rock failure process,based on statistical meso-damage model and finite element solver.The statistical approach is utilized to reflect the mesoscopic rock heterogeneity.The constitutive law of representative volume element(RVE)is established according to continuum damage mechanics in which double-damage criterion is considered.The damage evolution and accumulation of RVEs are used to reveal the macroscopic rock failure characteristics.Each single RVE will be represented by one unique element.The initiation,propagation and coalescence of meso-to macro-cracks are captured by smearing failed elements.The above ideas are formulated into the framework of the DSM and programed into self-developed rock failure process analysis(RFPA)software.Two laboratory-scale examples are conducted and the well-known engineering-scale tests,i.e.Atomic Energy of Canada Limited’s(AECL’s)Underground Research Laboratory(URL)tests,are used for verification.It shows that the simulation results match with other experimental results and field observations.展开更多
Objective To compare the performance of MTBDRplus V2 and Xpert MTB/RIF for detecting smear negative pulmonary tuberculosis （PTB）. Methods Clinical PTB suspects were enrolled consecutively in Anhui Chest Hospital and...Objective To compare the performance of MTBDRplus V2 and Xpert MTB/RIF for detecting smear negative pulmonary tuberculosis （PTB）. Methods Clinical PTB suspects were enrolled consecutively in Anhui Chest Hospital and Xi＇an Chest Hospital from January to December in 2014. The sputum samples of smear negative PTB suspects were collected and decontaminated. The sediment was used to conduct MTBDRplus V2, Xpert MTB/RIF and drug susceptibility test （DST）. All the samples with discrepant drug susceptibility result between molecular methods and phenotypic method were confirmed by DNA sequencing. Results A total of 1973 cases were enrolled in this study. The detection rates of Mycobacterium tuberculosis complex （MTBC） by MTBDRplus V2 and Xpert MTB/RIF were 27.67% and 27.98%, respectively. When setting MGIT culture result as a gold standard, the sensitivity and specificity of MTBDRplus V2 were 86.74% and 93.84%, and the sensitivity and specificity of Xpert MTB/RIF were 86.55% and 93.43%, respectively. For the detection of the resistance to rifampin, the sensitivity and specificity of MTBDRplus V2 were 94.34% and 96.62%, and the sensitivity and specificity of Xpert MTB/RIF were 88.68% and 95.96%, respectively. For the detection of the resistance to isoniazid, the sensitivity and specificity of MTBDRplus V2 were 77.38% and 98.02%, respectively. Conclusion MTBDRplus V2 and Xpert MTB/RIF can be used to detect MTBC in smear negative samples with satisfactory performance.展开更多
Introduction: Cancer of the cervix is the second most common gynecologic malignancy in the world due to lack of awareness and poor uptake of cervical cancer screening services especially in low income countries. In Ca...Introduction: Cancer of the cervix is the second most common gynecologic malignancy in the world due to lack of awareness and poor uptake of cervical cancer screening services especially in low income countries. In Cameroon, though there is a national cervical cancer-screening program the service has been limited to some main cities without an appreciable impact. Aims: The objectives of this study were to determine the knowledge, attitude, practice towards Pap smear screening, thus evaluating its suitability as a screening procedure in Cameroon, through this pilot study in the Buea Health District. Methods: The study was a community-based cross-sectional descriptive survey that involved 309 women. Women from 18 years were enrolled for the study from 9th?October to 20th?November 2013. Results: The mean age of the participants was 32.3 years (SD = 11.7 years). Most of the women (29.5%) who had gone for the Pap test were in the 41 - 50 years age group. Only 3.6% of the study participants had “good” knowledge of cervical cancer and Pap smear screening. Approximately 20% of the women had a previous Pap smear test with 55.7% of them having the test just once. Eighty two percent of those who had secondary and tertiary levels of education had never had a Pap smear test. Awareness of risk factors for cervical cancer was low. Fear of pain, positive results after screening, non-curability of cervical cancer were some factors associated with a low Pap test uptake (p < 0.05). Conclusion: There is poor knowledge and perceived barriers by women about Pap smear screening and follow-up services. For an impact to be made in the prevention of cervical cancer, Pap smear screening is not the preferred method because of these limitations in this community.展开更多
Introduction: Tuberculosis remains a public health problem in Zimbabwe. Understanding the treatment outcomes is an important proxy indicator on the performance of the tuberculosis program. This study analyzed treatmen...Introduction: Tuberculosis remains a public health problem in Zimbabwe. Understanding the treatment outcomes is an important proxy indicator on the performance of the tuberculosis program. This study analyzed treatment outcomes of new sputum smear positive tuberculosis patients in Kwekwe district. Materials and Methods: A retrospective records review of new sputum smear positive tuberculosis patients registered in the district tuberculosis register in Kwekwe was conducted. Treatment outcomes were categorized according to the national tuberculosis control program and multivariate logistic regression model was used. P values less than 0.05 were considered statistically significant. Results: From a total of 1115 new sputum smear positive tuberculosis patients, cure rate ranged from 40.8% to 62.8% and death rate of patients decreased from 11 (8.0%) in 2007 to 17 (5.3%) in 2011 (p = 0.016). However, defaulter rate increased from 10 (7.3%) in 2007 to 30 (9.3%) in 2011. In multivariate logistic model, HIV positive tuberculosis patients were more likely to experience (adjusted RR = 1.84, 95% CI: 1.10 - 3.08) unfavorable treatment outcome when compared to negative counterparts. Urban residents were also at risk 1.91 (95% CI: 1.14 - 3.20) unfavorable outcome compared to rural residents. Conclusion: The cure rate was low (ranged from 40.8% to 62.8%) and the defaulter rate needed urgent attention. The district should conduct defaulter tracing and follow up.展开更多
BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)is a safe and accurate technique to confirm the diagnosis of pancreatic cancers.Recently,numerous studies comparing the diagnostic efficacy o...BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)is a safe and accurate technique to confirm the diagnosis of pancreatic cancers.Recently,numerous studies comparing the diagnostic efficacy of smear cytology(SC)and liquid-based cytology(LBC)for pancreatic lesions yielded mixed results.AIM To compare and identify the better cytology method for EUS-FNA in pancreatic lesions.METHODS A comprehensive search of PubMed,Embase,and Cochrane was undertaken through July 18,2020.The primary endpoint was diagnostic accuracy(sensitivity and specificity).Secondary outcomes included sample adequacy and post procedure complications.In addition,factors affecting diagnostic efficacy were discussed.RESULTS Data on a total of 1121 comparisons from 10 studies met the inclusion criteria.Pooled rates of sensitivity for SC and LBC were 78%(67%-87%)vs 75%(67%-81%),respectively.In any case,both SC and LBC exhibited a high specificity close to 100%.Inadequate samples more often appeared in LBC compared with SC.However,the LBC samples exhibited a better visual field than SC.Very few post procedure complications were observed.CONCLUSION Our data suggested that for EUS-FNA in pancreatic lesions(particularly solid lesions),SC with Rapid On-Site Evaluation represents a superior diagnostic technique.If Rapid On-Site Evaluation is unavailable,LBC may replace smears.The diagnostic accuracy of LBC depends on different LBC techniques.展开更多
基金The authors wish to acknowledge the generous financial sup-port from the Singapore Maritime Institute(SMI)for this research within the project‘Evaluation of In-situ Consolidation of Dredged and Excavated Materials at Reclaimed Next Generation Tuas Port’(Project ID:SMI-2018-MA-01).
文摘Vertical drains are used to accelerate consolidation of clays in ground improvement projects.Smear zones exist around these drains,where permeability is reduced due to soil disturbance caused by the installation process.Hansbo solution is widely used in practice to consider the effects of drain discharge capacity and smear on the consolidation process.In this study,a computationally efficient diameter reduction method(DRM)obtained from the Hansbo solution is proposed to consider the smear effect without the need to model the smear zone physically.Validated by analytical and numerical results,a diameter reduction factor is analytically derived to reduce the diameter of the drain,while achieving similar solutions of pore pressure dissipation profile as the classical full model of the smear zone and drain.With the DRM,the excess pore pressure u obtained from the reduced drain in the original un-disturbed soil zone is accurate enough for practical applications in numerical models.Such performance of DRM is independent of soil material property.Results also show equally accurate performance of DRM under conditions of multi-layered soils and coupled radial-vertical groundwater flow.
基金supported by the 863 National Plan Foundation of China under Grant No.2007AA01Z333 and Special Grand National Project of China under Grant No.2009ZX02204-008.
文摘Blood smear test is the basic method of blood cytology and is also a standard medical test that can help diagnose various conditions and diseases.Morphological examination is the gold stan-dard to determine pathological changes in blood cell morphology.In the biology and medicine automation trend,blood smears'automated management and analysis is very necessary.An online blood smear automatic microscopic image detection system has been constructed.It includes an online blood smear automatic producing part and a blood smear automatic micro-scopic image detection part.Online identity authentication is at the core of the system.The identifiers printed online always present dot matrix digit code(DMDC)whose stroke is not continuous.Considering the particularities of DMDC and the complexities of online application environment,an online identity authentication method for blood smear with heterological theory is proposed.By synthesizing the certain regional features according to the heterological theory,high identification accuracy and high speed have been guaranteed with few features required.In the experiment,the suficient correct matches bet ween the tube barcode and the identification result verified its feasibility and validity.
基金supported by a research grant from the Office of the Vice-Chancellor for Research and Development,University of the Philippines-Diliman(Grant No.101007 PNSE)to W.L.R.and H.J.S
文摘Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.
基金supported by the Fundamental Research Funds for the Central Universities,China(No.2010JC030)
文摘Summary： This study was aimed to evaluate the effectiveness of solution form of 17% ethylenediaminetetraacetic acid （EDTA） on removing smear layer of root canals at different exposure time periods and to provide scientific basis for EDTA as a choice of root canal irrigation in clinical practice. Twenty-five single-rooted teeth were randomly divided into 5 groups： control group （group A） was given 2.5% NaOC1, and 4 experimental groups were given 2.5% NaOC1 and 17% EDTA, including groups B, C, D and E with exposure time of 1, 3, 5 and 7 min, respectively. After preparation of the root canals, the teeth were split along their longitudinal axis, and the root sections were examined under scanning elec- tron microscope for evaluation of smear layer removal and erosion on the surface of the root canal walls. The specimens in group B showed presence of smear layer on the walls of the root canal with no statistical difference from that in group A （P〉0.05）. In groups C and D, partial removal of smear layer was obtained, and there was no significant difference between the two groups （P〉0.05）, but there was significant difference in removal of smear layer between group C and group B （P〈0.05）. Root canal walls in group E specimens showed almost complete removal of smear layer, and the removal of smear layer was significantly different from that in group D （P〈0.01）. There was no significant change in the structure of the surface of root canal for each sample. It was concluded that combined irrigation with 17% EDTA and 2.5% NaOC1 could remove the smear layer with no significant alteration in dentinal structure when the chelating agent was applied for 7 min. At 3 and 5 min of application, partial removal of smear layer was observed and at 1 min negligible removal of smear layer was achieved.
基金supported in part by the National Natural Science Foundation of China (Grant Nos.51679028 and 51879034)Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology (Grant No. SKLGDUEK1804)the Fundamental Research Funds for the Central Universities (Grant No.DUT18JC10)
文摘Damage smear method(DSM)is adopted to study trans-scale progressive rock failure process,based on statistical meso-damage model and finite element solver.The statistical approach is utilized to reflect the mesoscopic rock heterogeneity.The constitutive law of representative volume element(RVE)is established according to continuum damage mechanics in which double-damage criterion is considered.The damage evolution and accumulation of RVEs are used to reveal the macroscopic rock failure characteristics.Each single RVE will be represented by one unique element.The initiation,propagation and coalescence of meso-to macro-cracks are captured by smearing failed elements.The above ideas are formulated into the framework of the DSM and programed into self-developed rock failure process analysis(RFPA)software.Two laboratory-scale examples are conducted and the well-known engineering-scale tests,i.e.Atomic Energy of Canada Limited’s(AECL’s)Underground Research Laboratory(URL)tests,are used for verification.It shows that the simulation results match with other experimental results and field observations.
文摘Objective To compare the performance of MTBDRplus V2 and Xpert MTB/RIF for detecting smear negative pulmonary tuberculosis （PTB）. Methods Clinical PTB suspects were enrolled consecutively in Anhui Chest Hospital and Xi＇an Chest Hospital from January to December in 2014. The sputum samples of smear negative PTB suspects were collected and decontaminated. The sediment was used to conduct MTBDRplus V2, Xpert MTB/RIF and drug susceptibility test （DST）. All the samples with discrepant drug susceptibility result between molecular methods and phenotypic method were confirmed by DNA sequencing. Results A total of 1973 cases were enrolled in this study. The detection rates of Mycobacterium tuberculosis complex （MTBC） by MTBDRplus V2 and Xpert MTB/RIF were 27.67% and 27.98%, respectively. When setting MGIT culture result as a gold standard, the sensitivity and specificity of MTBDRplus V2 were 86.74% and 93.84%, and the sensitivity and specificity of Xpert MTB/RIF were 86.55% and 93.43%, respectively. For the detection of the resistance to rifampin, the sensitivity and specificity of MTBDRplus V2 were 94.34% and 96.62%, and the sensitivity and specificity of Xpert MTB/RIF were 88.68% and 95.96%, respectively. For the detection of the resistance to isoniazid, the sensitivity and specificity of MTBDRplus V2 were 77.38% and 98.02%, respectively. Conclusion MTBDRplus V2 and Xpert MTB/RIF can be used to detect MTBC in smear negative samples with satisfactory performance.
文摘Introduction: Cancer of the cervix is the second most common gynecologic malignancy in the world due to lack of awareness and poor uptake of cervical cancer screening services especially in low income countries. In Cameroon, though there is a national cervical cancer-screening program the service has been limited to some main cities without an appreciable impact. Aims: The objectives of this study were to determine the knowledge, attitude, practice towards Pap smear screening, thus evaluating its suitability as a screening procedure in Cameroon, through this pilot study in the Buea Health District. Methods: The study was a community-based cross-sectional descriptive survey that involved 309 women. Women from 18 years were enrolled for the study from 9th?October to 20th?November 2013. Results: The mean age of the participants was 32.3 years (SD = 11.7 years). Most of the women (29.5%) who had gone for the Pap test were in the 41 - 50 years age group. Only 3.6% of the study participants had “good” knowledge of cervical cancer and Pap smear screening. Approximately 20% of the women had a previous Pap smear test with 55.7% of them having the test just once. Eighty two percent of those who had secondary and tertiary levels of education had never had a Pap smear test. Awareness of risk factors for cervical cancer was low. Fear of pain, positive results after screening, non-curability of cervical cancer were some factors associated with a low Pap test uptake (p < 0.05). Conclusion: There is poor knowledge and perceived barriers by women about Pap smear screening and follow-up services. For an impact to be made in the prevention of cervical cancer, Pap smear screening is not the preferred method because of these limitations in this community.
文摘Introduction: Tuberculosis remains a public health problem in Zimbabwe. Understanding the treatment outcomes is an important proxy indicator on the performance of the tuberculosis program. This study analyzed treatment outcomes of new sputum smear positive tuberculosis patients in Kwekwe district. Materials and Methods: A retrospective records review of new sputum smear positive tuberculosis patients registered in the district tuberculosis register in Kwekwe was conducted. Treatment outcomes were categorized according to the national tuberculosis control program and multivariate logistic regression model was used. P values less than 0.05 were considered statistically significant. Results: From a total of 1115 new sputum smear positive tuberculosis patients, cure rate ranged from 40.8% to 62.8% and death rate of patients decreased from 11 (8.0%) in 2007 to 17 (5.3%) in 2011 (p = 0.016). However, defaulter rate increased from 10 (7.3%) in 2007 to 30 (9.3%) in 2011. In multivariate logistic model, HIV positive tuberculosis patients were more likely to experience (adjusted RR = 1.84, 95% CI: 1.10 - 3.08) unfavorable treatment outcome when compared to negative counterparts. Urban residents were also at risk 1.91 (95% CI: 1.14 - 3.20) unfavorable outcome compared to rural residents. Conclusion: The cure rate was low (ranged from 40.8% to 62.8%) and the defaulter rate needed urgent attention. The district should conduct defaulter tracing and follow up.
文摘BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)is a safe and accurate technique to confirm the diagnosis of pancreatic cancers.Recently,numerous studies comparing the diagnostic efficacy of smear cytology(SC)and liquid-based cytology(LBC)for pancreatic lesions yielded mixed results.AIM To compare and identify the better cytology method for EUS-FNA in pancreatic lesions.METHODS A comprehensive search of PubMed,Embase,and Cochrane was undertaken through July 18,2020.The primary endpoint was diagnostic accuracy(sensitivity and specificity).Secondary outcomes included sample adequacy and post procedure complications.In addition,factors affecting diagnostic efficacy were discussed.RESULTS Data on a total of 1121 comparisons from 10 studies met the inclusion criteria.Pooled rates of sensitivity for SC and LBC were 78%(67%-87%)vs 75%(67%-81%),respectively.In any case,both SC and LBC exhibited a high specificity close to 100%.Inadequate samples more often appeared in LBC compared with SC.However,the LBC samples exhibited a better visual field than SC.Very few post procedure complications were observed.CONCLUSION Our data suggested that for EUS-FNA in pancreatic lesions(particularly solid lesions),SC with Rapid On-Site Evaluation represents a superior diagnostic technique.If Rapid On-Site Evaluation is unavailable,LBC may replace smears.The diagnostic accuracy of LBC depends on different LBC techniques.
