The aims of this study were to evaluate two methods, qPCR and a chemiluminescent assay (ColiLight II), for rapid detection of E. coli in water, and to examine the survival and persistence of clinical E. coli in drinki...The aims of this study were to evaluate two methods, qPCR and a chemiluminescent assay (ColiLight II), for rapid detection of E. coli in water, and to examine the survival and persistence of clinical E. coli in drinking water and biofilm using qPCR and ColiLight II. qPCR and ColiLight II were compared with a cultivation-based method (MPN), and survival and persistence of four clinical E. coli strains in water and biofilms on stainless steel (SS) and polyethylene (PE) surfaces were studied in a flow-through reactor with non-disinfected drinking water using ColiLight II, qPCR, ATP bioluminescence, and MPN. ColiLight II and qPCR correlated well with MPN. In drinking water, some clinical E. coli strains showed prolonged survival in drinking water flow-through systems, and persisted 3 - 3.4 times longer than the theoretical washout due to incorporation into biofilms. Strain specific attributes can significantly affect detection and persistence of E. coli in drinking water matrices.展开更多
AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We e...AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We enrolled 235 patients with HEV into a cross-sectional study using multi-stage sampling to select the study group.Patients with possible acute hepatitis E showing elevated liver enzyme levels were screened for HEV infection using serologic and molecular tools.HEV infection was documented by HEV antibodies and by the detection of HEV-RNA in serum.We used χ2 analysis,Fisher's exact test,and Student's t test where appropriate in this study.Significant predictors in the univariate analysis were then included in a forward,stepwise multiple logistic regression model.RESULTS:No significant differences in symptoms,alanine aminotransferase,aspartate aminotransferase,al-kaline phosphatase,or hepatitis B virus surface antigen between the two groups were observed.HEV infected patients with severe jaundice had significantly lower peak serum levels of γ-glutamyl-transpeptidase(GGT)(median:170.31 U/L vs 237.96 U/L,P = 0.007),significantly lower ALB levels(33.84 g/L vs 36.89 g/L,P = 0.000),significantly lower acetylcholine esterase(CHE) levels(4500.93 U/L vs 5815.28 U/L,P = 0.000) and significantly higher total bile acid(TBA) levels(275.56 μmol/L vs 147.03 μmol/L,P = 0.000) than those without severe jaundice.The median of the lowest point time tended to be lower in patients with severe jaundice(81.64% vs 96.12%,P = 0.000).HEV infected patients with severe jaundice had a significantly higher viral load(median:134 vs 112,P = 0.025) than those without severe jaundice.HEV infected patients with severe jaundice showed a trend toward longer median hospital stay(38.17 d vs 18.36 d,P = 0.073).Multivariate logistic regression indicated that there were significant differences in age,sex,viral load,GGT,albumin,TBA,CHE,prothrombin index,alcohol overconsumption,and duration of admission between patients infected with acute hepatitis E with and without severe jaundice.CONCLUSION:Acute hepatitis E patients may naturally present with severe jaundice.展开更多
Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The...Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical activity.The literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic cancers.These findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and treatment.The current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and metastasis.MEDLINE/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive benefits.Following an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.展开更多
Background and Aims Recently, epidemiology studies of hepatitis E in different areas are attracted more attention. Extensive studies of prevalent status and clinical manifestations could help us to broaden our knowled...Background and Aims Recently, epidemiology studies of hepatitis E in different areas are attracted more attention. Extensive studies of prevalent status and clinical manifestations could help us to broaden our knowledge, so as to excellently prevent and treat hepatitis E. The study analyzed the epidemiological characteristics and clinical features of 394 cases of sporadic acute hepatitis E(AHE) in Southwest of China from 2008 to 2010. Methods The clinical data of 394 cases with sporadic AHE in Southwest of China from 2008 to 2010 were reviewed.Results In the 394 cases with sporadic AHE, the ratio of male/female was 1.432∶1, and the mean age was(31.53 ± 18.12) years. Totally, 94(23.86%) patients aged under 18, 271(68.78%) patients aged between 18 and 60, and 29(7.36%) patients aged above 60. The incidence rate was significantly increased in summer(P = 0.000), especially in May(14.72%) and July(13.71%). In addition, the characteristics of occupation and ethnic group distribution were migrant laborers(106/394, 26.90%) and Han people(365/394, 92.64%). The length of stay, incidence of jaundice, the peak value of total bilirubin and alanine aminotransferase in male patients were all higher than those in female patients significantly(P < 0.05). The prolonged length of stay, decreased levels of ALT/ALB/CHE, increased levels of TBil, and increased incidence of jaundice and fatigue were associated with older age significantly(P < 0.05). The differences in peak values of total bilirubin(TBil), total bile acid(TBA), glutamyltransferase(GGT), cholinesterase(CHE) between AHE group and the groups of AHE accompanied respectively by chronic hepatitis B(CHB), acute alcoholic fatty liver(AFL), nonalcoholic fatty liver disease(NAFLD) were significant(P < 0.05). In addition, no significant difference was found in length of stay and biochemical indexes among anti-HEV-Ig G positive group, anti-HEV-Ig M positive group and antiHEV-Ig M/Ig G both positive group(P > 0.05).Conclusions Four epidemiological characteristics, including aged between 18 and 60, male, summer and migrant laborers, are found to be associated with acute hepatitis E. The prognosis of AHE in the majority of patients was favorable, but aged above 60 years and coexistence with CHB, AFL and NAFLD could be considerede as the factors inducing the infaust prognosis.展开更多
In the last decade, evidence-based medical practice has been supported on a large scale by computerized decision support tools, aiming to reduce diagnostic and therapeutic uncertainty, complementing the actions of the...In the last decade, evidence-based medical practice has been supported on a large scale by computerized decision support tools, aiming to reduce diagnostic and therapeutic uncertainty, complementing the actions of the health professional. With technological developments, it is now possible to consider these systems as part of clinical intervention, both for the diagnosis and treatment of diseases. The literature has described the implementation of e-health tools, that is, technological innovations in the health area such as software, applications, serious games, among others, as a strategy to improve the process and adherence to treatment. However, there is still no standardized instrument in Brazil that can be used to guide the development, from the research phase, and the implementation of these tools as a health intervention, also impacting patient outcomes. With the objective of investigating a new therapeutic and preventive form, based on intervention with a computerized system, this work proposes the creation of guidelines for the registration and implementation of e-health tools as a clinical intervention. The proposal aims to be able to assist in the reporting standardization from the development stage to the application of the e-health tool helping in the treatment of diseases, registering all the experience lived in the research and applying it in different contexts of health.展开更多
AIM:To investigate the influence of chronic hepatitis B virus(HBV)infection[based on the status of hepatitis B e antigen(HBeAg),HBV DNA,and cirrhosis]on superimposed acute hepatitis E.METHODS:A total of 294 patients w...AIM:To investigate the influence of chronic hepatitis B virus(HBV)infection[based on the status of hepatitis B e antigen(HBeAg),HBV DNA,and cirrhosis]on superimposed acute hepatitis E.METHODS:A total of 294 patients were recruited from the Department of Infectious Diseases of the Third Affiliated Hospital,Sun Yat-sen University,from January 2003 to January 2012.The patients were classified into two groups:an HBV+hepatitis E virus(HEV)group(a group with chronic HBV infection that was superinfected with acute hepatitis E,n=118)and an HEV group(a group with acute hepatitis E,n=176).We retrospectively analyzed and compared the clinical features of the two groups.Statistical analyses were performed using theχ2test or Fisher’s exact test for categorical variables and the Student’s t test forcontinuous variables.A P value<0.05 was considered statistically significant.RESULTS:The peak values of prothrombin time,serum total bilirubin,and Model for End-Stage Liver Disease scores were significantly higher in the HBV+HEV group.More patients in the HBV+HEV group had complications(39.8%vs 16.5%,P=0.000)and developed liver failure(35.6%vs 8.5%,P=0.000).Additionally,the mortality of the HBV+HEV group was significantly higher(20.3%vs 7.4%,P=0.002).Further analysis of the HBV+HEV group showed that there were no significant differences in complication occurrence,liver failure incidence,or mortality between patients with different HBeAg and HBV DNA statuses.However,in patients with underlying cirrhosis,complication occurrence and liver failure incidence significantly increased.In total,12.7%of the patients in the HBV+HEV group received anti-HBV treatment,but this therapy failed to reduce mortality in patients who developed liver failure.CONCLUSION:The presence of underlying cirrhosis in chronic HBV infection results in more severe clinical outcomes with superimposed acute hepatitis E.AntiHBV treatment cannot improve the prognosis of liver failure caused by HBV-HEV superinfection.展开更多
Hepatitis B virus(HBV)(sub)genotypes A1,D3 and E circulate in sub-Saharan Africa,the region with one of the highest incidences of HBV-associated hepatocellular carcinoma globally.Although genotype E was identified mor...Hepatitis B virus(HBV)(sub)genotypes A1,D3 and E circulate in sub-Saharan Africa,the region with one of the highest incidences of HBV-associated hepatocellular carcinoma globally.Although genotype E was identified more than 20 years ago,and is the most widespread genotype in Africa,it has not been extensively studied.The current knowledge status and gaps in its origin and evolution,natural history of infection,disease progression,response to antiviral therapy and vaccination are discussed.Genotype E is an African genotype,with unique molecular characteristics that is found mainly in Western and Central Africa and rarely outside Africa except in individuals of African descent.The low prevalence of this genotype in the African descendant populations in the New World,phylogeographic analyses,the low genetic diversity and evidence of remnants of genotype E in ancient HBV samples suggests the relatively recent reintroduction into the population.There is scarcity of information on the clinical and virological characteristics of genotype E-infected patients,disease progression and outcomes and efficacy of anti-HBV drugs.Individuals infected with genotype E have been characterised with high hepatitis B e antigen-positivity and high viral load with a lower end of treatment response to interferon-alpha.A minority of genotype E-infected participants have been included in studies in which treatment response was monitored.Of concern is that current guidelines do not consider patients infected with genotype E.Thus,there is an urgent need for further large-scale investigations into genotype E,the neglected genotype of HBV.展开更多
Considering the influence of the streaming potential and electroviscous effects, the analytical solutions for electromagnetohydrodynamic (EMHD) flows in parallel plate microchannels are obtained. The electrolyte solut...Considering the influence of the streaming potential and electroviscous effects, the analytical solutions for electromagnetohydrodynamic (EMHD) flows in parallel plate microchannels are obtained. The electrolyte solutions in the microchannels are taken as generalized Maxwell fluids, and slip boundary conditions are adopted. To accurately analyze the EMHD flow characteristics, the variation trends of the electroviscous effects with the corresponding parameters must be understood. The results show that the electroviscous effects increase with the increase in the relaxation time De, the slip coefficient , and the wall zeta potential 0. However, the increase in the inverse of the electrical double-layer (EDL) thickness K, the electrical oscillating Reynolds number Re, and the ionic P'eclet number Pe can decrease the electroviscous effects. We also demonstrate that the electroviscous effect on the EMHD flows of generalized Maxwell fluids is larger than that of Newtonian fluids. This work will be useful in designing EMHD flows in parallel plate microchannels.展开更多
The purpose of this study was to investigate the demand of application of e-wallet in domestic retail industry by examining the needs of adoption of small amount paying method and the reasons for customers’ using of ...The purpose of this study was to investigate the demand of application of e-wallet in domestic retail industry by examining the needs of adoption of small amount paying method and the reasons for customers’ using of IC stored value card in this industry and aimed at providing suggestions on the e-development of small amount paying methods for domestic retail and banking industries. This study was developed in a way that the model constructs in TAM were adapted to the context of using e-wallets for clinic fees. Scale items on the survey include those measuring perceived usefulness, perceived ease of use, a user's attitude toward using and intention. The questionnaire contains no identifying information about the individual participants. A total of 320 Taipei City Hospital patients’ feedbacks were collected. Results indicate most of the relationships in the proposed model are statistically significant and in the predicted directions. Each observed variables influence with two ways: direct effect and indirect effect, and the total effect is the sum of direct effect and indirect effect. The Main effect of most of these observed variables is direct effect, but the information technology experience with the perceived usefulness. In this study, it could be finding that the perceived usefulness, the perceiver ease of use is positively associated with users’ attitude toward using, and the perceiver ease of use is positively associated with the perceived usefulness. It means the useful and easily operation of payment clinic fees with e-wallet products (such as Taipei Easy Card) is very important for the users. Besides, the easier for e-wallet using, the more people think it is usefulness. This suggestion is the same as the point at issue of Davis [1]. The users’ attitude toward using is positively associated with the intention using.展开更多
文摘The aims of this study were to evaluate two methods, qPCR and a chemiluminescent assay (ColiLight II), for rapid detection of E. coli in water, and to examine the survival and persistence of clinical E. coli in drinking water and biofilm using qPCR and ColiLight II. qPCR and ColiLight II were compared with a cultivation-based method (MPN), and survival and persistence of four clinical E. coli strains in water and biofilms on stainless steel (SS) and polyethylene (PE) surfaces were studied in a flow-through reactor with non-disinfected drinking water using ColiLight II, qPCR, ATP bioluminescence, and MPN. ColiLight II and qPCR correlated well with MPN. In drinking water, some clinical E. coli strains showed prolonged survival in drinking water flow-through systems, and persisted 3 - 3.4 times longer than the theoretical washout due to incorporation into biofilms. Strain specific attributes can significantly affect detection and persistence of E. coli in drinking water matrices.
基金Supported by Basic and Clinical Research of Capital Medical University,No. 2010JL10,to Xu B
文摘AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We enrolled 235 patients with HEV into a cross-sectional study using multi-stage sampling to select the study group.Patients with possible acute hepatitis E showing elevated liver enzyme levels were screened for HEV infection using serologic and molecular tools.HEV infection was documented by HEV antibodies and by the detection of HEV-RNA in serum.We used χ2 analysis,Fisher's exact test,and Student's t test where appropriate in this study.Significant predictors in the univariate analysis were then included in a forward,stepwise multiple logistic regression model.RESULTS:No significant differences in symptoms,alanine aminotransferase,aspartate aminotransferase,al-kaline phosphatase,or hepatitis B virus surface antigen between the two groups were observed.HEV infected patients with severe jaundice had significantly lower peak serum levels of γ-glutamyl-transpeptidase(GGT)(median:170.31 U/L vs 237.96 U/L,P = 0.007),significantly lower ALB levels(33.84 g/L vs 36.89 g/L,P = 0.000),significantly lower acetylcholine esterase(CHE) levels(4500.93 U/L vs 5815.28 U/L,P = 0.000) and significantly higher total bile acid(TBA) levels(275.56 μmol/L vs 147.03 μmol/L,P = 0.000) than those without severe jaundice.The median of the lowest point time tended to be lower in patients with severe jaundice(81.64% vs 96.12%,P = 0.000).HEV infected patients with severe jaundice had a significantly higher viral load(median:134 vs 112,P = 0.025) than those without severe jaundice.HEV infected patients with severe jaundice showed a trend toward longer median hospital stay(38.17 d vs 18.36 d,P = 0.073).Multivariate logistic regression indicated that there were significant differences in age,sex,viral load,GGT,albumin,TBA,CHE,prothrombin index,alcohol overconsumption,and duration of admission between patients infected with acute hepatitis E with and without severe jaundice.CONCLUSION:Acute hepatitis E patients may naturally present with severe jaundice.
文摘Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical activity.The literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic cancers.These findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and treatment.The current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and metastasis.MEDLINE/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive benefits.Following an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.
基金supported by the Major Program of National High Technology Research and Development of China(No.2006AA02A209)
文摘Background and Aims Recently, epidemiology studies of hepatitis E in different areas are attracted more attention. Extensive studies of prevalent status and clinical manifestations could help us to broaden our knowledge, so as to excellently prevent and treat hepatitis E. The study analyzed the epidemiological characteristics and clinical features of 394 cases of sporadic acute hepatitis E(AHE) in Southwest of China from 2008 to 2010. Methods The clinical data of 394 cases with sporadic AHE in Southwest of China from 2008 to 2010 were reviewed.Results In the 394 cases with sporadic AHE, the ratio of male/female was 1.432∶1, and the mean age was(31.53 ± 18.12) years. Totally, 94(23.86%) patients aged under 18, 271(68.78%) patients aged between 18 and 60, and 29(7.36%) patients aged above 60. The incidence rate was significantly increased in summer(P = 0.000), especially in May(14.72%) and July(13.71%). In addition, the characteristics of occupation and ethnic group distribution were migrant laborers(106/394, 26.90%) and Han people(365/394, 92.64%). The length of stay, incidence of jaundice, the peak value of total bilirubin and alanine aminotransferase in male patients were all higher than those in female patients significantly(P < 0.05). The prolonged length of stay, decreased levels of ALT/ALB/CHE, increased levels of TBil, and increased incidence of jaundice and fatigue were associated with older age significantly(P < 0.05). The differences in peak values of total bilirubin(TBil), total bile acid(TBA), glutamyltransferase(GGT), cholinesterase(CHE) between AHE group and the groups of AHE accompanied respectively by chronic hepatitis B(CHB), acute alcoholic fatty liver(AFL), nonalcoholic fatty liver disease(NAFLD) were significant(P < 0.05). In addition, no significant difference was found in length of stay and biochemical indexes among anti-HEV-Ig G positive group, anti-HEV-Ig M positive group and antiHEV-Ig M/Ig G both positive group(P > 0.05).Conclusions Four epidemiological characteristics, including aged between 18 and 60, male, summer and migrant laborers, are found to be associated with acute hepatitis E. The prognosis of AHE in the majority of patients was favorable, but aged above 60 years and coexistence with CHB, AFL and NAFLD could be considerede as the factors inducing the infaust prognosis.
文摘In the last decade, evidence-based medical practice has been supported on a large scale by computerized decision support tools, aiming to reduce diagnostic and therapeutic uncertainty, complementing the actions of the health professional. With technological developments, it is now possible to consider these systems as part of clinical intervention, both for the diagnosis and treatment of diseases. The literature has described the implementation of e-health tools, that is, technological innovations in the health area such as software, applications, serious games, among others, as a strategy to improve the process and adherence to treatment. However, there is still no standardized instrument in Brazil that can be used to guide the development, from the research phase, and the implementation of these tools as a health intervention, also impacting patient outcomes. With the objective of investigating a new therapeutic and preventive form, based on intervention with a computerized system, this work proposes the creation of guidelines for the registration and implementation of e-health tools as a clinical intervention. The proposal aims to be able to assist in the reporting standardization from the development stage to the application of the e-health tool helping in the treatment of diseases, registering all the experience lived in the research and applying it in different contexts of health.
文摘AIM:To investigate the influence of chronic hepatitis B virus(HBV)infection[based on the status of hepatitis B e antigen(HBeAg),HBV DNA,and cirrhosis]on superimposed acute hepatitis E.METHODS:A total of 294 patients were recruited from the Department of Infectious Diseases of the Third Affiliated Hospital,Sun Yat-sen University,from January 2003 to January 2012.The patients were classified into two groups:an HBV+hepatitis E virus(HEV)group(a group with chronic HBV infection that was superinfected with acute hepatitis E,n=118)and an HEV group(a group with acute hepatitis E,n=176).We retrospectively analyzed and compared the clinical features of the two groups.Statistical analyses were performed using theχ2test or Fisher’s exact test for categorical variables and the Student’s t test forcontinuous variables.A P value<0.05 was considered statistically significant.RESULTS:The peak values of prothrombin time,serum total bilirubin,and Model for End-Stage Liver Disease scores were significantly higher in the HBV+HEV group.More patients in the HBV+HEV group had complications(39.8%vs 16.5%,P=0.000)and developed liver failure(35.6%vs 8.5%,P=0.000).Additionally,the mortality of the HBV+HEV group was significantly higher(20.3%vs 7.4%,P=0.002).Further analysis of the HBV+HEV group showed that there were no significant differences in complication occurrence,liver failure incidence,or mortality between patients with different HBeAg and HBV DNA statuses.However,in patients with underlying cirrhosis,complication occurrence and liver failure incidence significantly increased.In total,12.7%of the patients in the HBV+HEV group received anti-HBV treatment,but this therapy failed to reduce mortality in patients who developed liver failure.CONCLUSION:The presence of underlying cirrhosis in chronic HBV infection results in more severe clinical outcomes with superimposed acute hepatitis E.AntiHBV treatment cannot improve the prognosis of liver failure caused by HBV-HEV superinfection.
文摘Hepatitis B virus(HBV)(sub)genotypes A1,D3 and E circulate in sub-Saharan Africa,the region with one of the highest incidences of HBV-associated hepatocellular carcinoma globally.Although genotype E was identified more than 20 years ago,and is the most widespread genotype in Africa,it has not been extensively studied.The current knowledge status and gaps in its origin and evolution,natural history of infection,disease progression,response to antiviral therapy and vaccination are discussed.Genotype E is an African genotype,with unique molecular characteristics that is found mainly in Western and Central Africa and rarely outside Africa except in individuals of African descent.The low prevalence of this genotype in the African descendant populations in the New World,phylogeographic analyses,the low genetic diversity and evidence of remnants of genotype E in ancient HBV samples suggests the relatively recent reintroduction into the population.There is scarcity of information on the clinical and virological characteristics of genotype E-infected patients,disease progression and outcomes and efficacy of anti-HBV drugs.Individuals infected with genotype E have been characterised with high hepatitis B e antigen-positivity and high viral load with a lower end of treatment response to interferon-alpha.A minority of genotype E-infected participants have been included in studies in which treatment response was monitored.Of concern is that current guidelines do not consider patients infected with genotype E.Thus,there is an urgent need for further large-scale investigations into genotype E,the neglected genotype of HBV.
基金Project supported by the National Natural Science Foundation of China(Nos.11772162 and11472140)the Inner Mongolia Autonomous Region Grassland Talent of China(No.12000-12102013)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(No.2016MS0106)
文摘Considering the influence of the streaming potential and electroviscous effects, the analytical solutions for electromagnetohydrodynamic (EMHD) flows in parallel plate microchannels are obtained. The electrolyte solutions in the microchannels are taken as generalized Maxwell fluids, and slip boundary conditions are adopted. To accurately analyze the EMHD flow characteristics, the variation trends of the electroviscous effects with the corresponding parameters must be understood. The results show that the electroviscous effects increase with the increase in the relaxation time De, the slip coefficient , and the wall zeta potential 0. However, the increase in the inverse of the electrical double-layer (EDL) thickness K, the electrical oscillating Reynolds number Re, and the ionic P'eclet number Pe can decrease the electroviscous effects. We also demonstrate that the electroviscous effect on the EMHD flows of generalized Maxwell fluids is larger than that of Newtonian fluids. This work will be useful in designing EMHD flows in parallel plate microchannels.
基金This work was supported by the National Key Research and Development Program of China(No.2019YFA0708703)the National Natural Science Foundation of China(No.21773309)the Hefei National Laboratory for Physical Sciences at the Microscale(KF2020004).
文摘The purpose of this study was to investigate the demand of application of e-wallet in domestic retail industry by examining the needs of adoption of small amount paying method and the reasons for customers’ using of IC stored value card in this industry and aimed at providing suggestions on the e-development of small amount paying methods for domestic retail and banking industries. This study was developed in a way that the model constructs in TAM were adapted to the context of using e-wallets for clinic fees. Scale items on the survey include those measuring perceived usefulness, perceived ease of use, a user's attitude toward using and intention. The questionnaire contains no identifying information about the individual participants. A total of 320 Taipei City Hospital patients’ feedbacks were collected. Results indicate most of the relationships in the proposed model are statistically significant and in the predicted directions. Each observed variables influence with two ways: direct effect and indirect effect, and the total effect is the sum of direct effect and indirect effect. The Main effect of most of these observed variables is direct effect, but the information technology experience with the perceived usefulness. In this study, it could be finding that the perceived usefulness, the perceiver ease of use is positively associated with users’ attitude toward using, and the perceiver ease of use is positively associated with the perceived usefulness. It means the useful and easily operation of payment clinic fees with e-wallet products (such as Taipei Easy Card) is very important for the users. Besides, the easier for e-wallet using, the more people think it is usefulness. This suggestion is the same as the point at issue of Davis [1]. The users’ attitude toward using is positively associated with the intention using.
