In this paper,we study the B→D^(*) l-l -ι semileptonic decays and calculate the branching ratios B(B→D^(*) l-l -ι) and the ratios R(D^(*)) and R_D^( l,s) by employing the perturbative QCD(pQCD)factorization appro...In this paper,we study the B→D^(*) l-l -ι semileptonic decays and calculate the branching ratios B(B→D^(*) l-l -ι) and the ratios R(D^(*)) and R_D^( l,s) by employing the perturbative QCD(pQCD)factorization approach.We find that(a)for R(D)and R(D*)ratios,the pQCD predictions are R(D)=0.430-0.026?0.021,R(D*)=0.301±0.013 and agree well with BaBar’s measurements of ReD e?T T;(b)for the newly defined R_D^1 and R_D^s ratios,the pQCD predictions are R_D^l=0.450-0.051+0.064 and R_D^s=0.642-0.070+0.081,which may be more sensitive to the QCD dynamics of the considered semileptonic decays than R(D^(*)) and should be tested by experimental measurements.展开更多
<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversigh...<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversight and lack of awareness of some of the disease conditions that might have been present in the country. This study sought to investigate the seroprevalence of dengue virus, geographical location of participants with circulating antibodies and finally evaluate the diagnostic accuracy of a Rapid diagnostic kit (RDT) using Enzyme Linked Immuno-Sorbent Assay (ELISA) as a gold standard for confirmation. <strong>Method: </strong>A hospital-based cross-sectional study was conducted among adults (≥18) attending the University of Cape Coast Hospital. From each participant, 3 - 4 ml of venous blood was drawn and serum was tested for IgG and IgM using RDT methods. Positive samples were selected for ELISA confirmation. Statistical analysis was performed using SPSS (v.20) and STATA (v.14) software. <strong>Results: </strong>A total of 270 participants were enrolled in the study. The geometric mean age was 32 years. Overall, Dengue virus (DENV) IgG seroprevalence by RDT was 10 (3.7%). Seroprevalence of IgG and IgM by the ELISA method was 34 (12.6%) and 6 (2.2%) respectively. Females recorded a high seroprevalence (7.4%) than males (5.2%) in terms of past exposure (IgG). On current exposure (IgM), females recorded a high seroprevalence (1.5%) than males (0.7%). Seroprevalence of individuals with dual positivity ((IgG + IgM+) (acute secondary infection) was 1.9%. Those with primary and recent infection (IgM+ only) were 0.4% whiles those with past and probably secondary infection (IgG+ only) were 10.7%. The odds of dengue exposure were significantly high among participants with ages 50 - 59 as compared to their other counterparts (AOR = 3.5, p = 0.03). Diagnostic accuracy of RDT kit was poor (Kappa value = 0.373 and 0.0001). Elmina was noted to record the highest seroprevalence values for both anti-dengue IgG (3.3%) and IgM (1.展开更多
The Random Decrement Technique （RDT）, based on decentralized computing approaches implemented in wireless sensor networks （WSNs）, has shown advantages for modal parameter and data aggregation identification. Howev...The Random Decrement Technique （RDT）, based on decentralized computing approaches implemented in wireless sensor networks （WSNs）, has shown advantages for modal parameter and data aggregation identification. However, previous studies of RDT-based approaches from ambient vibration data are based on the assumption of a broad-band stochastic process input excitation. The process normally is modeled by filtered white or white noise. In addition, the choice of the triggering condition in RDT is closely related to data communication. In this project, research has been conducted to study the nonstationary white noise excitations as the input to verify the random decrement technique. A local extremum triggering condition is chosen and implemented for the purpose of minimum data communication in a RDT-based distributed computing strategy. Numerical simulation results show that the proposed technique is capable of minimizing the amount of data transmitted over the network with accuracy in modal parameters identification.展开更多
Introduction: In sub-Saharan Africa, 80% to 85% of RDT negative febrile patients, seen in outpatient clinics, were given anti-malarial medicines. Previous studies recommended investigating determinants of “compliance...Introduction: In sub-Saharan Africa, 80% to 85% of RDT negative febrile patients, seen in outpatient clinics, were given anti-malarial medicines. Previous studies recommended investigating determinants of “compliance with RDT’ results” in specific cadre and setting, as intervention is most effective when context specific. Compliance with malaria RDT results and correlates among clinicians in Uyo was determined. Methods: A cross-sectional study of clinicians selected using stratified sampling. Data were collected using self-administered, semi-structured questionnaire on socio-demographics, facility audit of RDT supplies, knowledge, perception and practice of clinicians. Outcome variable of interest was whether or not clinicians self-reported compliance with RDT results. Exposure variables of interest were whether or not clinicians received RDT training;received supportive supervision for malaria RDT;had positive perception of RDT usefulness;had good knowledge of RDT use (scores of ≥75% in questions testing for knowledge);had readily available treatment guidelines;had diagnostic capacity for other common febrile illness;experienced patient overload;experienced stock-out of supplies;work in the private/public sector. Descriptive, bivariate and multivariate analyses were conducted. Results: Mean age of the clinicians was 33.0 years ± (6.0 SD). Of the total clinicians, 31.1% were female;66.0% received RDT training;36.4% had supportive supervision;43.3% exhibited good knowledge of RDT use;45.3% had positive perception of RDT usefulness and 41.7% relied on presumptive diagnosis. Compliances with RDT negative and positive results were 66.4% and 83.4% respectively. Compliance with RDT negative result was more in clinicians with good knowledge of RDT use (aOR = 25.0;95% CI = 2.92 - 213.52). Compliance with RDT positive result was more in clinicians with good knowledge of RDT use (aOR = 10.0;95% CI =2.70 - 18.72), positive perception of RDT usefulness (aOR = 10.2;95%CI =3.50 - 29.63) and in health facilities in the展开更多
<strong>Background of Study: </strong>The reliability of microscopic techniques has become questionable in most endemic regions in Africa leading to its decreased utilization and increased utilization of R...<strong>Background of Study: </strong>The reliability of microscopic techniques has become questionable in most endemic regions in Africa leading to its decreased utilization and increased utilization of RDT kits and other laboratory-based methods. <strong>Objective: </strong>To evaluate the performance of Rapid Diagnostic Test (RDT) kits and nest Polymerase Chain Reaction (nPCR) methods in detecting malaria infections among pregnant women visiting private hospitals in Onitsha district area of Anambra State, South-Eastern Nigeria. <strong>Methods:</strong> A total of 100 blood samples of pregnant women submitted to medical laboratory units of private maternal hospitals for malaria diagnosis in Onitsha district area were randomly selected for this study. Diagnosis was through microscopy, RDT kit (SD Bioline Pf-only test) and nPCR. <strong>Results: </strong>Pregnant cohorts had 95, 90 and 12 positive samples confirmed through microscopy RDT and nPCR respectively. RDT had a sensitivity and specificity of 89.47% and 0% while nPCR recorded sensitivity and specificity of 12.63% and 100% respectively. RDT and nPCR have a positive predictive value (PPV) of 94.44% of 100% respectively. <strong>Conclusion: </strong>This study revealed that nPCR is more efficient and reliable when compared with RDT in the diagnosis of malaria infection, having recorded the highest value for positive predictive value (PPV) and specificity than the RDT among pregnant women.展开更多
<strong>Introduction:</strong> Malaria is a febrile illness caused by the <em>Plasmodium</em> species. The mangrove swamp forest vegetation and high annual rainfall characteristic of the Niger ...<strong>Introduction:</strong> Malaria is a febrile illness caused by the <em>Plasmodium</em> species. The mangrove swamp forest vegetation and high annual rainfall characteristic of the Niger Delta region of Nigeria encourage all year round transmission of malaria. This study aimed to determine the prevalence and speciation of <em>Plasmodium</em> parasitaemia among pregnant women in the Niger Delta region of Nigeria. <strong>Methodology:</strong> Cross-sectional study carried out in three states of the Niger Delta region;Akwa-Ibom, Delta and Rivers between April and June 2019. Study Sites were chosen by stratified random sampling. Demographic information was collected using pretested interviewer-administered questionnaires via the Open Data Kit application on android mobile phones. Diagnosis was by rapid diagnostic test (RDT) and Microscopy. Ethical approval and informed consent were obtained. Data was analyzed using the SPSS v25 software. Chi-square statistic and Fischer’s exact test were used to compare data, all at a 95% confidence interval and significance level of 0.05. <strong>Results:</strong> Two thousand, eight hundred and twenty (2820) pregnant women were studied;948, 992 and 880 from Akwa-Ibom, Delta and Rivers respectively. Overall prevalence of parasitaemia using RDT and Microscopy was 6.8% and 6.7% respectively. All except 1% of malaria was attributed to falciparum species. The other species were plasmodium ovale and plasmodium malariae. <strong>Conclusion:</strong> The prevalence of <em>Plasmodium</em> parasitaemia among pregnant women in the Niger Delta region of Nigeria has reduced considerably, giving credence to the malaria preventive strategies applied in antenatal care. When properly stored and used as recommended, malaria RDTs compare favorably with microscopy;therefore, no case of malaria should be missed due to a facility’s incapability to carry out microscopic diagnosis.展开更多
Under India’s National AIDS Control Program (NACP), WHO recommended strategy of using three rapid tests is adopted for diagnosis of HIV in an asymptomatic individual. Since the NACP has a stringent kit evaluation pro...Under India’s National AIDS Control Program (NACP), WHO recommended strategy of using three rapid tests is adopted for diagnosis of HIV in an asymptomatic individual. Since the NACP has a stringent kit evaluation procedure and due to the availability of newer third generation Rapid Diagnostic Tests (RDTs) it may be possible to adapt two test strategy for HIV diagnosis instead of the recommended three test strategy. The authors reviewed programmatic data on HIV testing to explore whether use of two rapid tests for HIV diagnosis as against three tests could be a feasible approach without compromising the quality and readability of testing. Data on the HIV diagnosis performed on serum specimens collected for the period of one year (2011-12) from 82 Integrated Testing and Counselling Centers (ICTCs) or Prevention of Parent to Child Transmission Centers (PPTCTs) associated with State reference Laboratories (SRLs) was analysed. Out of 654258 results that were analysed 25168 (3.84%) specimens were positives. It was observed that both two and three test algorithms provided similar results for majority (>99%) of the HIV positive specimens. Discordance was observed in labelling of specimen with inconclusive status (N = 21), however the true status of these samples could not be obtained. The analysis indicated that the use of two test algorithm will have programmatic benefits in terms of reduced financial burden to the programme and ease of procurement, shipment and storage before and after distribution without comprising the quality of the testing. The prospective study would confirm this observation.展开更多
基金supported by the National Natural Science Foundation of China(10975074 and 11235005)
文摘In this paper,we study the B→D^(*) l-l -ι semileptonic decays and calculate the branching ratios B(B→D^(*) l-l -ι) and the ratios R(D^(*)) and R_D^( l,s) by employing the perturbative QCD(pQCD)factorization approach.We find that(a)for R(D)and R(D*)ratios,the pQCD predictions are R(D)=0.430-0.026?0.021,R(D*)=0.301±0.013 and agree well with BaBar’s measurements of ReD e?T T;(b)for the newly defined R_D^1 and R_D^s ratios,the pQCD predictions are R_D^l=0.450-0.051+0.064 and R_D^s=0.642-0.070+0.081,which may be more sensitive to the QCD dynamics of the considered semileptonic decays than R(D^(*)) and should be tested by experimental measurements.
文摘<strong>Introduction: </strong>Most febrile illnesses in Ghana are often misdiagnosed and presumptively treated as malaria. This situation may be due to the inappropriate diagnostic tool, clinical oversight and lack of awareness of some of the disease conditions that might have been present in the country. This study sought to investigate the seroprevalence of dengue virus, geographical location of participants with circulating antibodies and finally evaluate the diagnostic accuracy of a Rapid diagnostic kit (RDT) using Enzyme Linked Immuno-Sorbent Assay (ELISA) as a gold standard for confirmation. <strong>Method: </strong>A hospital-based cross-sectional study was conducted among adults (≥18) attending the University of Cape Coast Hospital. From each participant, 3 - 4 ml of venous blood was drawn and serum was tested for IgG and IgM using RDT methods. Positive samples were selected for ELISA confirmation. Statistical analysis was performed using SPSS (v.20) and STATA (v.14) software. <strong>Results: </strong>A total of 270 participants were enrolled in the study. The geometric mean age was 32 years. Overall, Dengue virus (DENV) IgG seroprevalence by RDT was 10 (3.7%). Seroprevalence of IgG and IgM by the ELISA method was 34 (12.6%) and 6 (2.2%) respectively. Females recorded a high seroprevalence (7.4%) than males (5.2%) in terms of past exposure (IgG). On current exposure (IgM), females recorded a high seroprevalence (1.5%) than males (0.7%). Seroprevalence of individuals with dual positivity ((IgG + IgM+) (acute secondary infection) was 1.9%. Those with primary and recent infection (IgM+ only) were 0.4% whiles those with past and probably secondary infection (IgG+ only) were 10.7%. The odds of dengue exposure were significantly high among participants with ages 50 - 59 as compared to their other counterparts (AOR = 3.5, p = 0.03). Diagnostic accuracy of RDT kit was poor (Kappa value = 0.373 and 0.0001). Elmina was noted to record the highest seroprevalence values for both anti-dengue IgG (3.3%) and IgM (1.
基金National Key Technology R&D Program of China under Grant No.2014BAL05B06Guangdong Science&Technology Program under Grant No.2014A050503016the Shenzhen Science&Technology Program under Grant No.GJHZ20150312114346635
文摘The Random Decrement Technique （RDT）, based on decentralized computing approaches implemented in wireless sensor networks （WSNs）, has shown advantages for modal parameter and data aggregation identification. However, previous studies of RDT-based approaches from ambient vibration data are based on the assumption of a broad-band stochastic process input excitation. The process normally is modeled by filtered white or white noise. In addition, the choice of the triggering condition in RDT is closely related to data communication. In this project, research has been conducted to study the nonstationary white noise excitations as the input to verify the random decrement technique. A local extremum triggering condition is chosen and implemented for the purpose of minimum data communication in a RDT-based distributed computing strategy. Numerical simulation results show that the proposed technique is capable of minimizing the amount of data transmitted over the network with accuracy in modal parameters identification.
文摘Introduction: In sub-Saharan Africa, 80% to 85% of RDT negative febrile patients, seen in outpatient clinics, were given anti-malarial medicines. Previous studies recommended investigating determinants of “compliance with RDT’ results” in specific cadre and setting, as intervention is most effective when context specific. Compliance with malaria RDT results and correlates among clinicians in Uyo was determined. Methods: A cross-sectional study of clinicians selected using stratified sampling. Data were collected using self-administered, semi-structured questionnaire on socio-demographics, facility audit of RDT supplies, knowledge, perception and practice of clinicians. Outcome variable of interest was whether or not clinicians self-reported compliance with RDT results. Exposure variables of interest were whether or not clinicians received RDT training;received supportive supervision for malaria RDT;had positive perception of RDT usefulness;had good knowledge of RDT use (scores of ≥75% in questions testing for knowledge);had readily available treatment guidelines;had diagnostic capacity for other common febrile illness;experienced patient overload;experienced stock-out of supplies;work in the private/public sector. Descriptive, bivariate and multivariate analyses were conducted. Results: Mean age of the clinicians was 33.0 years ± (6.0 SD). Of the total clinicians, 31.1% were female;66.0% received RDT training;36.4% had supportive supervision;43.3% exhibited good knowledge of RDT use;45.3% had positive perception of RDT usefulness and 41.7% relied on presumptive diagnosis. Compliances with RDT negative and positive results were 66.4% and 83.4% respectively. Compliance with RDT negative result was more in clinicians with good knowledge of RDT use (aOR = 25.0;95% CI = 2.92 - 213.52). Compliance with RDT positive result was more in clinicians with good knowledge of RDT use (aOR = 10.0;95% CI =2.70 - 18.72), positive perception of RDT usefulness (aOR = 10.2;95%CI =3.50 - 29.63) and in health facilities in the
文摘<strong>Background of Study: </strong>The reliability of microscopic techniques has become questionable in most endemic regions in Africa leading to its decreased utilization and increased utilization of RDT kits and other laboratory-based methods. <strong>Objective: </strong>To evaluate the performance of Rapid Diagnostic Test (RDT) kits and nest Polymerase Chain Reaction (nPCR) methods in detecting malaria infections among pregnant women visiting private hospitals in Onitsha district area of Anambra State, South-Eastern Nigeria. <strong>Methods:</strong> A total of 100 blood samples of pregnant women submitted to medical laboratory units of private maternal hospitals for malaria diagnosis in Onitsha district area were randomly selected for this study. Diagnosis was through microscopy, RDT kit (SD Bioline Pf-only test) and nPCR. <strong>Results: </strong>Pregnant cohorts had 95, 90 and 12 positive samples confirmed through microscopy RDT and nPCR respectively. RDT had a sensitivity and specificity of 89.47% and 0% while nPCR recorded sensitivity and specificity of 12.63% and 100% respectively. RDT and nPCR have a positive predictive value (PPV) of 94.44% of 100% respectively. <strong>Conclusion: </strong>This study revealed that nPCR is more efficient and reliable when compared with RDT in the diagnosis of malaria infection, having recorded the highest value for positive predictive value (PPV) and specificity than the RDT among pregnant women.
文摘<strong>Introduction:</strong> Malaria is a febrile illness caused by the <em>Plasmodium</em> species. The mangrove swamp forest vegetation and high annual rainfall characteristic of the Niger Delta region of Nigeria encourage all year round transmission of malaria. This study aimed to determine the prevalence and speciation of <em>Plasmodium</em> parasitaemia among pregnant women in the Niger Delta region of Nigeria. <strong>Methodology:</strong> Cross-sectional study carried out in three states of the Niger Delta region;Akwa-Ibom, Delta and Rivers between April and June 2019. Study Sites were chosen by stratified random sampling. Demographic information was collected using pretested interviewer-administered questionnaires via the Open Data Kit application on android mobile phones. Diagnosis was by rapid diagnostic test (RDT) and Microscopy. Ethical approval and informed consent were obtained. Data was analyzed using the SPSS v25 software. Chi-square statistic and Fischer’s exact test were used to compare data, all at a 95% confidence interval and significance level of 0.05. <strong>Results:</strong> Two thousand, eight hundred and twenty (2820) pregnant women were studied;948, 992 and 880 from Akwa-Ibom, Delta and Rivers respectively. Overall prevalence of parasitaemia using RDT and Microscopy was 6.8% and 6.7% respectively. All except 1% of malaria was attributed to falciparum species. The other species were plasmodium ovale and plasmodium malariae. <strong>Conclusion:</strong> The prevalence of <em>Plasmodium</em> parasitaemia among pregnant women in the Niger Delta region of Nigeria has reduced considerably, giving credence to the malaria preventive strategies applied in antenatal care. When properly stored and used as recommended, malaria RDTs compare favorably with microscopy;therefore, no case of malaria should be missed due to a facility’s incapability to carry out microscopic diagnosis.
文摘Under India’s National AIDS Control Program (NACP), WHO recommended strategy of using three rapid tests is adopted for diagnosis of HIV in an asymptomatic individual. Since the NACP has a stringent kit evaluation procedure and due to the availability of newer third generation Rapid Diagnostic Tests (RDTs) it may be possible to adapt two test strategy for HIV diagnosis instead of the recommended three test strategy. The authors reviewed programmatic data on HIV testing to explore whether use of two rapid tests for HIV diagnosis as against three tests could be a feasible approach without compromising the quality and readability of testing. Data on the HIV diagnosis performed on serum specimens collected for the period of one year (2011-12) from 82 Integrated Testing and Counselling Centers (ICTCs) or Prevention of Parent to Child Transmission Centers (PPTCTs) associated with State reference Laboratories (SRLs) was analysed. Out of 654258 results that were analysed 25168 (3.84%) specimens were positives. It was observed that both two and three test algorithms provided similar results for majority (>99%) of the HIV positive specimens. Discordance was observed in labelling of specimen with inconclusive status (N = 21), however the true status of these samples could not be obtained. The analysis indicated that the use of two test algorithm will have programmatic benefits in terms of reduced financial burden to the programme and ease of procurement, shipment and storage before and after distribution without comprising the quality of the testing. The prospective study would confirm this observation.
