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A simulation study of disaggregation regression for spatial disease mapping. Stat Med 2021; 41:1-16. [PMID: 34658042 DOI: 10.1002/sim.9220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/30/2021] [Accepted: 09/20/2021] [Indexed: 11/07/2022]
Abstract
Disaggregation regression has become an important tool in spatial disease mapping for making fine-scale predictions of disease risk from aggregated response data. By including high resolution covariate information and modeling the data generating process on a fine scale, it is hoped that these models can accurately learn the relationships between covariates and response at a fine spatial scale. However, validating these high resolution predictions can be a challenge, as often there is no data observed at this spatial scale. In this study, disaggregation regression was performed on simulated data in various settings and the resulting fine-scale predictions are compared to the simulated ground truth. Performance was investigated with varying numbers of data points, sizes of aggregated areas and levels of model misspecification. The effectiveness of cross validation on the aggregate level as a measure of fine-scale predictive performance was also investigated. Predictive performance improved as the number of observations increased and as the size of the aggregated areas decreased. When the model was well-specified, fine-scale predictions were accurate even with small numbers of observations and large aggregated areas. Under model misspecification predictive performance was significantly worse for large aggregated areas but remained high when response data was aggregated over smaller regions. Cross-validation correlation on the aggregate level was a moderately good predictor of fine-scale predictive performance. While these simulations are unlikely to capture the nuances of real-life response data, this study gives insight into the effectiveness of disaggregation regression in different contexts.
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Predicting non-state terrorism worldwide. SCIENCE ADVANCES 2021; 7:7/31/eabg4778. [PMID: 34330703 PMCID: PMC8324061 DOI: 10.1126/sciadv.abg4778] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 06/15/2021] [Indexed: 06/13/2023]
Abstract
Several thousand people die every year worldwide because of terrorist attacks perpetrated by non-state actors. In this context, reliable and accurate short-term predictions of non-state terrorism at the local level are key for policy makers to target preventative measures. Using only publicly available data, we show that predictive models that include structural and procedural predictors can accurately predict the occurrence of non-state terrorism locally and a week ahead in regions affected by a relatively high prevalence of terrorism. In these regions, theoretically informed models systematically outperform models using predictors built on past terrorist events only. We further identify and interpret the local effects of major global and regional terrorism drivers. Our study demonstrates the potential of theoretically informed models to predict and explain complex forms of political violence at policy-relevant scales.
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Systemic Therapy of Dermtophytosis with Voriconaole: A Clinical Observational Study of 250 Bangladeshi Patients. Mymensingh Med J 2021; 30:738-743. [PMID: 34226463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Superficial fungal infection or dermatophytosis is one of the most common dermatological problems in a tropical country like Bangladesh. For last 4-5 years this skin problem is on rise with increase in cases of recalcitrant, recurrent and chronic dermatophytosis. In place of an easy task to treat dermatophytosis recently it has evolved into difficult to treat by traditional antifungal agents. Meanwhile, voriconazole, primarily appeared as an agent for deep fungal infections, has come out as a new promising systemic antifungal drug for dermatophytosis also. In Bangladesh recently an endeavor has been made to treat superficial fungal infection with voriconazole. Two hundred and ninety four patients suffering from recalcitrant, recurrent, resistant and chronic dermatophytosis between 12 and 70 years of age and both sexes were selected for the study between August 2018 and November 2018 from different parts of the country. Two categories of therapy were designed: Group A - 200mg 12 hourly for 14 days and Group B - 200mg 12 hourly for 28 days. Patients showing full response in 2 weeks were declared apparently cured and were kept under follow up. Those who did not show significant response (less than 50% improvement) in 2 weeks were considered failed. Unresponsive cases after 28 days were considered failed. Both groups were followed up for 4 weeks. Cases not showing any activity of the disease and negative microscopy on two occasions at 2 weeks interval were considered cured. Two hundred and fifty patients completed the study. Incidence of cure rate was more in Group B (93.04%) which is statistically significant (p<0.005). Relapse rate was observed more in Group A (22.83%). Visual side effects were 4.4% while vertigo and headache were observed in 12.0% and 10.8% respectably. Voriconazole is a promising treatment option for recurrent, recalcitrant and chronic dermatophytosis in dosage of 200mg twice daily for at least 4 weeks with negligible side effects. More diversified studies with longer follow up period is required for further opinion to establish an authenticated dosage schedule for treatment of superficial fungal infection.
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Mapping malaria by sharing spatial information between incidence and prevalence data sets. J R Stat Soc Ser C Appl Stat 2021. [DOI: 10.1111/rssc.12484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Global estimation of anti-malarial drug effectiveness for the treatment of uncomplicated Plasmodium falciparum malaria 1991-2019. Malar J 2020; 19:374. [PMID: 33081784 PMCID: PMC7573874 DOI: 10.1186/s12936-020-03446-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/10/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Anti-malarial drugs play a critical role in reducing malaria morbidity and mortality, but their role is mediated by their effectiveness. Effectiveness is defined as the probability that an anti-malarial drug will successfully treat an individual infected with malaria parasites under routine health care delivery system. Anti-malarial drug effectiveness (AmE) is influenced by drug resistance, drug quality, health system quality, and patient adherence to drug use; its influence on malaria burden varies through space and time. METHODS This study uses data from 232 efficacy trials comprised of 86,776 infected individuals to estimate the artemisinin-based and non-artemisinin-based AmE for treating falciparum malaria between 1991 and 2019. Bayesian spatiotemporal models were fitted and used to predict effectiveness at the pixel-level (5 km × 5 km). The median and interquartile ranges (IQR) of AmE are presented for all malaria-endemic countries. RESULTS The global effectiveness of artemisinin-based drugs was 67.4% (IQR: 33.3-75.8), 70.1% (43.6-76.0) and 71.8% (46.9-76.4) for the 1991-2000, 2006-2010, and 2016-2019 periods, respectively. Countries in central Africa, a few in South America, and in the Asian region faced the challenge of lower effectiveness of artemisinin-based anti-malarials. However, improvements were seen after 2016, leaving only a few hotspots in Southeast Asia where resistance to artemisinin and partner drugs is currently problematic and in the central Africa where socio-demographic challenges limit effectiveness. The use of artemisinin-based combination therapy (ACT) with a competent partner drug and having multiple ACT as first-line treatment choice sustained high levels of effectiveness. High levels of access to healthcare, human resource capacity, education, and proximity to cities were associated with increased effectiveness. Effectiveness of non-artemisinin-based drugs was much lower than that of artemisinin-based with no improvement over time: 52.3% (17.9-74.9) for 1991-2000 and 55.5% (27.1-73.4) for 2011-2015. Overall, AmE for artemisinin-based and non-artemisinin-based drugs were, respectively, 29.6 and 36% below clinical efficacy as measured in anti-malarial drug trials. CONCLUSIONS This study provides evidence that health system performance, drug quality and patient adherence influence the effectiveness of anti-malarials used in treating uncomplicated falciparum malaria. These results provide guidance to countries' treatment practises and are critical inputs for malaria prevalence and incidence models used to estimate national level malaria burden.
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Improved long-term time-series predictions of total blood use data from England. Transfusion 2020; 60:2307-2318. [PMID: 32691487 DOI: 10.1111/trf.15966] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/25/2020] [Accepted: 06/03/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Red blood cells are essential for modern medicine but managing their collection and supply to cope with fluctuating demands represents a major challenge. As deterministic models based on predicted population changes have been problematic, there remains a need for more precise and reliable prediction of use. Here, we develop three new time-series methods to predict red cell use 4 to 52 weeks ahead. STUDY DESIGN AND METHODS From daily aggregates of red blood cell (RBC) units issued from 2005 to 2011 from the NHS Blood and Transplant, we generated a new set of non-overlapping weekly data by summing the daily data over 7 days and derived the average blood use per week over 4-week and 52-week periods. We used three new methods for linear prediction of blood use by computing the coefficients using Minimum Mean Squared Error (MMSE) algorithm. RESULTS We optimized the time-window size, order of the prediction, and order of the polynomial fit for our data set. By exploiting the annual periodicity of the data, we achieved significant improvements in long-term predictions, as well as modest improvements in short-term predictions. The new methods predicted mean RBC use with a standard deviation of the percentage error of 2.5% for 4 weeks ahead and 3.4% for 52 weeks ahead. CONCLUSION This paradigm allows short- and long-term prediction of RBC use and could provide reliable and precise prediction up to 52 weeks ahead to improve the efficiency of blood services and sufficiency of blood supply with reduced costs.
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Improving disaggregation models of malaria incidence by ensembling non-linear models of prevalence. Spat Spatiotemporal Epidemiol 2020; 41:100357. [PMID: 35691633 PMCID: PMC9205339 DOI: 10.1016/j.sste.2020.100357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/13/2020] [Accepted: 06/18/2020] [Indexed: 10/24/2022]
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Efficacy of Itraconazole in the Prevention of Recurrence of Tinea Versicolor: A Three Year Follow Up. Mymensingh Med J 2020; 29:351-356. [PMID: 32506089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Pityriasis versicolor (PV) also known as tinea versicolor, which is chronic and superficial fungal skin disease caused by Malassezia yeasts. A permanent cure may difficult to achieve and this may explain the long-term nature of the disease. Consequently, a preventive treatment regimen may help to prevent the recurrence of pityriasis versicolor. Whether, the recurrence of tinea versicolor could be prevented by monthly itraconazole treatment regimen after a short course of itraconazole therapy. Open treatment followed by a randomized, single blind placebo control trial. Multi-center trial was characterized by an open, active treatment phase with itraconazole followed by a randomized placebo controlled treatment for prevention of recurrence. A total 200 patients (150 male and 50 female) were included in this study and was given 200mg itraconazole daily for 7 days (treatment phase). Patients in whom tinea versicolor was mycologically cured divided into Group A and Group B. Active open treatment was followed by preventive itraconazole treatment 200mg twice daily in Group A and placebo in Group B monthly for 6 consecutive months. The patients were diagnosed clinically and confirmed by Wood's lamp examination and KOH microscopy. Clinical improvement in 90%, negative Wood's lamp examination in 86.5% and Mycological cure in 85.5% were found at the end of open treatment. The mycological cure, 171 subjects were taken into this study for preventive treatment phase and divided into two groups- Group A & Group B. Preventive treatment was given in Group A and placebo in Group B. After the preventive treatment, the end point (After 6 months), clinical improvement, negative Wood's lamp examination and mycological cure were found in 81(90%), 76(84.4%) and 75(83.3%) in Group A and 44(55%), 41(51.3%) and 42(52.5%) in Group B respectively. In preventive treatment phase, 1 patient in Group A did not complete the study. No patient experienced any serious adverse effects. Prevention of recurrence of Pityriasis versicolor with itraconazole is as effective as treatment.
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Efficacy of Fexofenadine in the Treatment of Chronic Idiopathic Urticaria. Mymensingh Med J 2020; 29:414-419. [PMID: 32506098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Urticaria is a common clinical condition that gives a major concern for physicians and patients alike. Urticaria is referred to as chronic when wheals occur daily or almost daily for a period of at least six weeks. The primary purpose of this study is to find out the efficacy of fexofenadine in the treatment of chronic idiopathic urticaria patients among the Bangladeshi population. This quasi-experimental study was performed in the Department of Dermatology & Venereology, Shaheed Ziaur Rahman Medical College Hospital, Bogura, Bangladesh from July 2013 to December 2013. Total 100 patients of chronic idiopathic urticaria aged 18 years and above with exclusion and inclusion criteria were selected. Then they were given fexofenadine 120mg twice daily for the treatment of chronic idiopathic urticaria for four weeks. A semi quantitative rating scales were used for the assessment of therapeutic efficacy before and after treatment. Data were collected in a pre-designed questionnaire by face-to-face interview and analyzed by the help of SPSS. Among the 100 respondents after one week of treatment, 8.0% had complete disappearance of symptoms, 10.0% had marked improvement, 40.0% had moderate improvement and 42.0% had slight improvement. After two weeks of treatment 35.0% had complete disappearance of symptoms, 13.0% had marked improvement, 12.0% had moderate improvement and 40.0% had slight improvement. After three weeks of treatment 40.0% had complete disappearance of symptoms, 13.0% had marked improvement, 35.0% had moderate improvement and 12.0% had slight improvement. After four weeks of treatment 42.0% had complete disappearance of symptoms, 24.0% had marked improvement, 26.0% had moderate improvement and 8.0% had slight improvement. The study concluded that fexofenadine is very effective in the treatment of chronic idiopathic urtecaria.
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Prediction paradigm involving time series applied to total blood issues data from England. Transfusion 2020; 60:535-543. [PMID: 32067239 PMCID: PMC7079144 DOI: 10.1111/trf.15705] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 01/20/2023]
Abstract
BACKGROUND Blood products are essential for modern medicine, but managing their collection and supply in the face of fluctuating demands represents a major challenge. As deterministic models based on predicted changes in population have been problematic, there remains a need for more precise and reliable prediction of demands. Here, we propose a paradigm incorporating four different time‐series methods to predict red blood cell (RBC) issues 4 to 24 weeks ahead. STUDY DESIGN AND METHODS We used daily aggregates of RBC units issued from 2005 to 2011 from the National Health Service Blood and Transplant. We generated a new set of nonoverlapping weekly data by summing the daily data over 7 days and derived the average blood issues per week over 4‐week periods. We used four methods for linear prediction of blood demand by computing the coefficients with the minimum mean squared error and weighted least squares error algorithms. RESULTS We optimized the time‐window size, order of the prediction, and order of the polynomial fit for our data set. The four time‐series methods, essentially using different weightings to data points, gave very similar results and predicted mean RBC issues with a standard deviation of the percentage error of 3.0% for 4 weeks ahead and 4.0% for 24 weeks ahead. CONCLUSION This paradigm allows prediction of demand for RBCs and could be developed to provide reliable and precise prediction up to 24 weeks ahead to improve the efficiency of blood services and sufficiency of blood supply with reduced costs.
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Comorbidities in Patients with Psoriasis. Mymensingh Med J 2019; 28:894-899. [PMID: 31599257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Psoriasis, a chronic inflammatory disease is associated with a long list of comorbidities. In our practice we like to draw attention in comorbidities of psoriatic arthritis and we are adapted with cardiovascular comorbidities. A great deal remains unknown about psoriasis associated comorbidities. An understanding of these comorbidity patterns can help us to ensure better care of patients with psoriasis. Objective of the study was to find out the comorbid conditions in the patients of psoriasis. This observational case control study was conducted 150 diagnosed cases of psoriasis and 150 age matched healthy control. Purposively 150 patients of psoriasis were selected from the Dermatology OPD of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2017 to December 2018 as case. After a complete physical examination, a pre-designed structured questionnaire was fulfilled with patients and controls. To detect unknown comorbidities the following tests was done in both groups and compared: Blood sugar, urine routine and microscopic examination, serum creatinine, serum AST, ALT, GGT, and ALP levels measured by an enzymatic method, X-ray chest view, USG of whole abdomen/KUB. The diagnosed comorbidity was listed and referred for treatment accordingly. Charlson-age comorbidity index chart was used to estimate risk of mortality in two groups. The mean age of incident psoriasis was 38.64 years. Diabetes mellitus (4.67%), hypertension (4%), ischemic heart disease (IHD) (3.33%) were the top three comorbidities in patients with psoriasis. among them 11(7.33%) patients of psoriasis was with single comorbidity and 5(3.33%) of them was with multiple comorbidity. In control group 3(2%) participants was detected with comorbidity and that difference was significant statistically. In current study Charlson-Age Comorbidity index (CACI) was used as a tool to estimate the risk of mortality in two groups. The mean CACI score was 2.5 and 1 in two groups respectively and the difference was significant (p<0.05). The estimated risk of death (ERRD) score was calculated form CACI chart and the score was 2.78 and 1.47 in two groups respectively. There was no significant difference in two groups (p>0.05). The rate of occurrence of comorbidity was more in psoriasis group than in control. The listed comorbidity was in mild severity range but the risk of mortality was same in psoriasis group and control.
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Mapping the global endemicity and clinical burden of Plasmodium vivax, 2000-17: a spatial and temporal modelling study. Lancet 2019; 394:332-343. [PMID: 31229233 PMCID: PMC6675736 DOI: 10.1016/s0140-6736(19)31096-7] [Citation(s) in RCA: 221] [Impact Index Per Article: 44.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 04/12/2019] [Accepted: 04/24/2019] [Indexed: 01/12/2023]
Abstract
BACKGROUND Plasmodium vivax exacts a significant toll on health worldwide, yet few efforts to date have quantified the extent and temporal trends of its global distribution. Given the challenges associated with the proper diagnosis and treatment of P vivax, national malaria programmes-particularly those pursuing malaria elimination strategies-require up to date assessments of P vivax endemicity and disease impact. This study presents the first global maps of P vivax clinical burden from 2000 to 2017. METHODS In this spatial and temporal modelling study, we adjusted routine malariometric surveillance data for known biases and used socioeconomic indicators to generate time series of the clinical burden of P vivax. These data informed Bayesian geospatial models, which produced fine-scale predictions of P vivax clinical incidence and infection prevalence over time. Within sub-Saharan Africa, where routine surveillance for P vivax is not standard practice, we combined predicted surfaces of Plasmodium falciparum with country-specific ratios of P vivax to P falciparum. These results were combined with surveillance-based outputs outside of Africa to generate global maps. FINDINGS We present the first high-resolution maps of P vivax burden. These results are combined with those for P falciparum (published separately) to form the malaria estimates for the Global Burden of Disease 2017 study. The burden of P vivax malaria decreased by 41·6%, from 24·5 million cases (95% uncertainty interval 22·5-27·0) in 2000 to 14·3 million cases (13·7-15·0) in 2017. The Americas had a reduction of 56·8% (47·6-67·0) in total cases since 2000, while South-East Asia recorded declines of 50·5% (50·3-50·6) and the Western Pacific regions recorded declines of 51·3% (48·0-55·4). Europe achieved zero P vivax cases during the study period. Nonetheless, rates of decline have stalled in the past five years for many countries, with particular increases noted in regions affected by political and economic instability. INTERPRETATION Our study highlights important spatial and temporal patterns in the clinical burden and prevalence of P vivax. Amid substantial progress worldwide, plateauing gains and areas of increased burden signal the potential for challenges that are greater than expected on the road to malaria elimination. These results support global monitoring systems and can inform the optimisation of diagnosis and treatment where P vivax has most impact. FUNDING Bill & Melinda Gates Foundation and the Wellcome Trust.
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Mapping the global prevalence, incidence, and mortality of Plasmodium falciparum, 2000-17: a spatial and temporal modelling study. Lancet 2019; 394:322-331. [PMID: 31229234 PMCID: PMC6675740 DOI: 10.1016/s0140-6736(19)31097-9] [Citation(s) in RCA: 216] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 04/12/2019] [Accepted: 04/24/2019] [Indexed: 01/26/2023]
Abstract
BACKGROUND Since 2000, the scale-up of malaria control interventions has substantially reduced morbidity and mortality caused by the disease globally, fuelling bold aims for disease elimination. In tandem with increased availability of geospatially resolved data, malaria control programmes increasingly use high-resolution maps to characterise spatially heterogeneous patterns of disease risk and thus efficiently target areas of high burden. METHODS We updated and refined the Plasmodium falciparum parasite rate and clinical incidence models for sub-Saharan Africa, which rely on cross-sectional survey data for parasite rate and intervention coverage. For malaria endemic countries outside of sub-Saharan Africa, we produced estimates of parasite rate and incidence by applying an ecological downscaling approach to malaria incidence data acquired via routine surveillance. Mortality estimates were derived by linking incidence to systematically derived vital registration and verbal autopsy data. Informed by high-resolution covariate surfaces, we estimated P falciparum parasite rate, clinical incidence, and mortality at national, subnational, and 5 × 5 km pixel scales with corresponding uncertainty metrics. FINDINGS We present the first global, high-resolution map of P falciparum malaria mortality and the first global prevalence and incidence maps since 2010. These results are combined with those for Plasmodium vivax (published separately) to form the malaria estimates for the Global Burden of Disease 2017 study. The P falciparum estimates span the period 2000-17, and illustrate the rapid decline in burden between 2005 and 2017, with incidence declining by 27·9% and mortality declining by 42·5%. Despite a growing population in endemic regions, P falciparum cases declined between 2005 and 2017, from 232·3 million (95% uncertainty interval 198·8-277·7) to 193·9 million (156·6-240·2) and deaths declined from 925 800 (596 900-1 341 100) to 618 700 (368 600-952 200). Despite the declines in burden, 90·1% of people within sub-Saharan Africa continue to reside in endemic areas, and this region accounted for 79·4% of cases and 87·6% of deaths in 2017. INTERPRETATION High-resolution maps of P falciparum provide a contemporary resource for informing global policy and malaria control planning, programme implementation, and monitoring initiatives. Amid progress in reducing global malaria burden, areas where incidence trends have plateaued or increased in the past 5 years underscore the fragility of hard-won gains against malaria. Efforts towards elimination should be strengthened in such areas, and those where burden remained high throughout the study period. FUNDING Bill & Melinda Gates Foundation.
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Relating N 2O emissions during biological nitrogen removal with operating conditions using multivariate statistical techniques. WATER RESEARCH 2018; 140:387-402. [PMID: 29754044 DOI: 10.1016/j.watres.2018.04.052] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/07/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Multivariate statistical analysis was applied to investigate the dependencies and underlying patterns between N2O emissions and online operational variables (dissolved oxygen and nitrogen component concentrations, temperature and influent flow-rate) during biological nitrogen removal from wastewater. The system under study was a full-scale reactor, for which hourly sensor data were available. The 15-month long monitoring campaign was divided into 10 sub-periods based on the profile of N2O emissions, using Binary Segmentation. The dependencies between operating variables and N2O emissions fluctuated according to Spearman's rank correlation. The correlation between N2O emissions and nitrite concentrations ranged between 0.51 and 0.78. Correlation >0.7 between N2O emissions and nitrate concentrations was observed at sub-periods with average temperature lower than 12 °C. Hierarchical k-means clustering and principal component analysis linked N2O emission peaks with precipitation events and ammonium concentrations higher than 2 mg/L, especially in sub-periods characterized by low N2O fluxes. Additionally, the highest ranges of measured N2O fluxes belonged to clusters corresponding with NO3-N concentration less than 1 mg/L in the upstream plug-flow reactor (middle of oxic zone), indicating slow nitrification rates. The results showed that the range of N2O emissions partially depends on the prior behavior of the system. The principal component analysis validated the findings from the clustering analysis and showed that ammonium, nitrate, nitrite and temperature explained a considerable percentage of the variance in the system for the majority of the sub-periods. The applied statistical methods, linked the different ranges of emissions with the system variables, provided insights on the effect of operating conditions on N2O emissions in each sub-period and can be integrated into N2O emissions data processing at wastewater treatment plants.
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Current Trends of Using Systemic Antifungal Drugs and their Comparative Efficacy in Tinea Corporis and Tinea Cruris in Outpatient Department of Dermatology in a Tertiary Level Hospital. Mymensingh Med J 2018; 27:52-56. [PMID: 29459592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Tinea corporis & cruris are one of the earliest known fungal infection and are very common throughout the world. Although tinea corporis and tinea cruris does not cause mortality but causes morbidity and poses a major health problem. This study was conducted to evaluate the Comparative Efficacy of Terbinafine and Fluconazole in the Treatment of Tinea corporis and Tinea cruris. This cross sectional comparative type of analytical study was carried out at the department of Pharmacology & Therapeutics with collaboration of Dermatology and Venereology in Mymensingh Medical College Hospital, Mymensingh, Bangladesh from January 2016 to December 2016. In this study 168 newly diagnosed Tinea corporis and Tinea cruris patient was purposively selected where pattern of comparative efficacy of terbinafine and fluconazole were analyzed. Among 168 patients most of the patients presented with tinea corporis (58.33%). Most patients belong to 21-30 years age group. Male female ratio in this study was 1.15:1. In this study 143 patients were treated by fluconazole 50mg once daily for 4 weeks and 25 patients were treated by terbinafine 250 mg once daily for 4 weeks. After 4 weeks, improvement rate by fluconazole was 86.02% and terbinafine 96.00%. The clinical score of both groups after 4th week of treatment, there was slight more reduction of clinical score in terbinafine using group than fluconazole using group. The difference between these two clinical score was not statistically significant (p>0.05). Although no significant difference was observed between these two groups of patient in clinical aspect, but due to its lower price and availability in the hospital, it is suggested that fluconazole is more suitable for the treatment of tinea corporis and tinea cruris.
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Skin Biopsy and Histopathological Diagnosis of Dermatological Diseases. Mymensingh Med J 2018; 27:41-45. [PMID: 29459590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Microscopic examination of skin and mucous membrane is an established investigation in diagnosis and follow up of many dermatological conditions frequently encountered during practice. Histopathological examination is performed with biopsied specimen from skin and or mucous membrane where required. However neither do all skin biopsies produce neither a conclusive diagnosis nor the dermatologists routinely perform this procedure to every patient they consult. This cross sectional descriptive study conducted by reviewing the records of all biopsied cases studied for histopathology in Mymensingh Medical College, Mymensingh and Shaheed Mansur Ali Medical College, Dhaka, Bangladesh from January 2012 to December 2016. The aim of this study was to investigate the favourable clinical diagnoses set by dermatologists when performing skin biopsy, the diagnoses reached by the dermatopathologists after microscopic examination, and the relationship between them and finally to comment on the instances that skin biopsy fails to fulfill the diagnostic task. Fourteen hundred and thirty six (1436) cases of skin biopsy were reviewed and descriptive statistics were performed. Maximum cases 39.1% (562) were in 2nd decade with almost equal sex distribution. The most frequently proposed clinical diagnoses included papulosquamous dermatoses 28.6% (410), whereas histological confirmation was in 13.1% (188). Histological diagnosis was more as nonspecific dermatitis 31.6% (454). After microscopic examination, a specific histological diagnosis was found in 83.5% (1199) of the cases and a consensus between clinical and histological diagnoses was observed in 69.2% (994). Neither histological diagnosis nor any feature consistent with clinical suspicion was observed in 10.1% (145) cases. Histopathological examination of skin biopsy is still a valuable diagnostic tool in many skin diseases and dermatoses with diagnostic dilemma. There are cases in which diagnostic inefficiency are being faced even after skin biopsy examination.
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Sexual Lifestyle, Risk Factors and Socioeconomic Status of the STD Patients in Bangladesh. Mymensingh Med J 2017; 26:21-28. [PMID: 28260751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sexually transmitted diseases (STDs) are increasing alarmingly with time among the young-adults in Bangladesh. The objective of the study was to investigate Sexual lifestyle, Risk Factors and Socioeconomic Status of the STD Patients. A total of 205 STD patients were selected following convenient method of sampling consistent with defined selection criteria from outpatient department of Skin and Venereal Disease of Mymensingh Medical College Hospital, Mymensingh. Period of data collection was from July 2014 to June 2015. The research instrument was an interviewer questionnaire and laboratory investigation reports. Results showed that the mean age of the respondents was 27±5.9 years of which 104(50.7%) unmarried and 95(46.3%) married. Level of education, 168(82.0%) of the STD patients were literate. Occupation of the STD patients, 201(98.0%) had specific occupation of which 74(36.1%) were businessmen, 48(23.4%) student, 24(11.7%) technical jobs, 20(9.8%) day labourer, 15(7.3%) household workers, 14(6.8%) service holders and 6(2.9%) were transport workers. Their average monthly income was Tk. 7892±6763. Majority of the STD patients 115((56.1%) expressed that they enjoyed extra-marital sex or illegal sex out of curiosity, 32(15.6%) habitual, 24(11.7%) to test sexual performance, 18(8.8%) inadequate response of the legal sex partners, 8(3.9%) hyper-sexuality and 8(3.9%) family disharmony. Most of the patients 200(97.6%) were heterosexual of which 165(80.5%) visited 1-10 sex partners, 18(8.8%) 11-20 sex partners and 22(10.7%) visited 21-100 sex partners in lifetime. In category of sex partners, 60(29.3%) were hotel-based sex partners, 111(54.1%) brothel-based, 20(9.8%) friends sex partners, 10(4.9%) street sex sellers and 4(2.0%) were residential sex partners respectively. Of them, 132(64.4%) did not use condom during sex, 65(31.7%) use it occasionally and only 8(3.9%) use condom regularly. Most of them 170((82.8%) had been suffering from gonococcal urethritis, 19(9.3%) non-gonococcal urethritis, 12(5.9%) genital herpes, and rest other specific infections. STDs were significantly (p<0.05) associated with category of sex partners and use of condom. Altering sexual lifestyle is still the only applicable way to stop this human catastrophe.
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Effectiveness of Topical Corticosteroid, Topical Calcineurin Inhibitors and Combination of Them in the Treatment of Vitiligo. Mymensingh Med J 2016; 25:620-627. [PMID: 27941720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Vitiligo is an acquired pigmentary skin disorder which is disfiguring and difficult to treat. Cure and response rates for vitiligo are significantly lower. This study was conducted to evaluate the effectiveness of topical corticosteroid, topical calcineurin inhibitors (tacrolimus) and combination of them in the treatment of vitilligo in two tertiary care Hospital, in the Department of Dermatology and Venereology OPD (out patient department) in Mymensingh Medical College Hospital and Jahurul Islam Medical College Hospital, Bajitpur, Kishoregonj from January 2015 to December 2015. Newly diagnosed 112 vitiligo patients, aged more than 1 year to 70 years were assigned for therapy and to observe the response. This study indicates that, in case of vitiligo treatment topical tacrolimus was the most effective drug. Topical tacrolimus, topical corticosteroid and combination of them are to be effective in the treatment of vitiligo with reduction in the number of vitiliginous spots by increased repigmentation. But topical tacrolimus was the most effective drug, as it caused highest percentage of repigmentation of vitiliginous spot.
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Hepatitis-B Infections among the Injection Drug Abusers: An Emerging Risk in Public Health, Bangladesh. Mymensingh Med J 2015; 24:813-824. [PMID: 26620025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The objective of the study was to determine the incidence of Hepatitis-B (HBV) infection among the injection drugs abusers (IDUs). The research work was a cross-sectional study. A total of 400 IDUs were selected from July 2012 to June 2013 at the Outpatient Department of the Central Drug Addiction Treatment Center, Tejgaon, Dhaka, Bangladesh. They were selected consecutively following the purposive sampling method on the basis of defined selection criteria. Research instruments were a pre-tested interviewer questionnaire and blood specimen. Results showed that 79.70%(315) of the IDUs were found literate and 20.3%(85) illiterate. In present occupation, majority of them 60.5%(242) had no work and 39.5%(158) specific occupation. The mean age of them was 27.9±6.4 years. In marital status, 46.5%(186) were unmarried, 20.7%(83) married after addiction and 30.3%(121) married before addiction. Majority of the IDUs 75.2%(289) started their addiction with cannabis. In addition to injection drugs use, all of them were multiple drug abusers. In response to the sharing of needle, 35.7%(143) of the IDUs shared needle uncommonly and 64.3%(257) did not shared it at all. Ninety-three percent (372) of them were heterosexual and polygamous having extramarital sex with multiple partners. The quality of sex-partners was wife, friends, brothel & hotel based sex sellers and street sex sellers. Majority of IDUs {82.0%(328)} did not use condom at all and 15.5(62) sold blood several times in their lifetime. Seven percent {7.0%(28)} injection drug abusers had been suffering from hepatitis-B virus (HBV) infection. HBV infection was found to be significantly (p≥0.05) associated with the quality of sex partners and number of sex partners, and age and marital status. There is no significant association with sharing of needle particularly occasional sharing of needle. Altering the behaviors of IDUs, especially their sexual lifestyles, drug habit, using of disposable syringe without sharing of needle, and also alternative preventive measures against injection drugs are still the applicable way to control spread of the HBV among the IDUs in Bangladesh.
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Topical Tacrolimus versus Hydrocortisone on Atopic Dermatitis in Paediatric Patients: A Randomized Controlled Trial. Mymensingh Med J 2015; 24:457-463. [PMID: 26329939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Atopic dermatitis (AD) is a chronic, inflammatory skin disease in early childhood. Atopic dermatitis is familial disease, often coexists with other atopic diseases with multiple risk factors associated with atopic eczema. The disease is more frequent in urban areas compared with rural areas. Changes in nutrition and a decrease in infant breast-feeding and respiratory allergies are contributory factors for the condition. A Randomized Controlled Trial (RCT) was carried to compare the efficacy and safety of Tacrolimus ointment with a topical corticosteroid reference therapy. A total 60 patients aged between 2 to 10 years, having atopic dermatitis for at least one year and comply Hanifin-Rajka criteria were selected using random number table and allocated into study and control groups through randomization. Study group was treated with topical Tacrolimus 0.03% twice daily for three weeks, while the control group was treated with 1% Hydrocortisone acetate for the same period. Both groups had a washed out phase for 2 weeks with a follow up period of 6 weeks. Eczema Area and Severity lndex (EASI) was assessed at baseline and three weeks after treatment. Efficacy was evaluated at each visit by six clinical signs of atopic dermatitis through measurement of the affected surface area and the EASI score in each of four body regions. Before intervention, in study group mean EASI score was 11.29 with a SD of 2.14, while in control group it was 11.05 with a SD of 2.46. Difference was statistically insignificant (p>0.05). At the end of the treatment, in study group mean EASI score was 4.86 with a SD of 1.01, while in control group it was 7.97 with a SD of 1.80. Statistically high significant difference was observed between EASI scores of two groups before and after the treatment (p<0.001). After getting treatment with Tacrolimus, median reduction of EASI score was 56.07 in study group, while getting treatment with Hydrocortisone, median reduction of EASI score was 27.16. Difference was highly significant (p<0.001). It is evidenced that Tacrolimus ointment (0.03%) acts as an effective as well as safe non-steroidal topical therapy for the treatment of dermatitis in paediatric patients.
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Cutaneous anthrax in a school teacher. Mymensingh Med J 2014; 23:372-374. [PMID: 24858169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Cutaneous anthrax is an infection of the skin caused by Bacillus anthracis. This is a report of a case of cutaneous anthrax attending outpatients of Mymensingh Medical College Hospital in October, 2010. The infected person was a retired school teacher with a very good body build. He reported to handle cow flesh about 4-5 days ago, developed few painless papules over shin of right leg, which gradually became large bullae and blackish eschar developed over the lesion. Smears from the lesions were investigated which confirmed the causative agent B. anthracis. The patient was treated with oral Ciprofloxacin (500mg) twice daily for seven days which cured the infection as observed on his subsequent follow up visits on 7 and 14 days later. Oral Ciprofloxacin is found effective as recommended by the World Health Organization.
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Abstracts of Presentations at the International Conference on Basic and Clinical Multimodal Imaging (BaCI), a Joint Conference of the International Society for Neuroimaging in Psychiatry (ISNIP), the International Society for Functional Source Imaging (ISFSI), the International Society for Bioelectromagnetism (ISBEM), the International Society for Brain Electromagnetic Topography (ISBET), and the EEG and Clinical Neuroscience Society (ECNS), in Geneva, Switzerland, September 5-8, 2013. Clin EEG Neurosci 2013; 44:1550059413507209. [PMID: 24368763 DOI: 10.1177/1550059413507209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Pattern of mental illness on substance abusers. Mymensingh Med J 2012; 21:251-258. [PMID: 22561767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The aim of this study was to investigate mental illnesses among the substance abuse dependent populations. A total of 1076 substance abusers were recruited from the Outpatient Department of the Central Drug Addiction Treatment Center, Tejgaon, Dhaka from July 2008 to June 2009. They sought detoxification therapy voluntarily at this centre. The research participants were selected consecutively following the defined selection criteria. Research instruments were interviewer-administered questionnaire and standard mental state examination scales. Of the 1076 substance abusers, 82.6% had been using heroin currently and rest of them used phensedyl followed by injection drugs and cannabis with a period ranged 2-30 years. Results showed that 91.3% of the substance abusers had been suffering from insomnia and 75.0% had altered food habit. About 49.0% showed disturbed behaviors and 45.2% had been suffering from sexual dysfunctions. Around 32.0% of the substance abusers had been suffering from nonspecific generalized anxieties and 72.7% were found in abnormal mood/affects. A striking finding was that 7.3% of the substance abusers had been suffering from perceptual and/or thought disturbances. In conclusion, 7.3%-92.5% of the substance abusers had been suffering from mental illnesses. Insomnias, decreased intake of food and taste preference, irritable mood/affects, loss of interest in sex and non-specific anxieties were highly prevalent among them. Medical management and altering lifestyle are still the only applicable way to control this human catastrophe.
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Instability of human rotavirus G genotypes circulating in a rural area of Bangladesh. Mymensingh Med J 2011; 20:1-8. [PMID: 21240155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A total of 280 fecal specimens from patients with acute gastroenteritis attending one rural hospital (Dharmapasha health complex, Sunamgonj) in Bangladesh from August 2004 to May 2006 were tested for rotavirus by Polyacrylamide Gel Electrophoresis (PAGE). The diversity of rotavirus was investigated using electropherotyping and reverse transcription-PCR amplification of the VP7 and VP4 genes. The electrophoretic patterns of dsRNA of rotavirus showed 9 different migrations (6 long and 3 short) by PAGE. In the year 2004-2006, group A rotavirus was detected in 112 out of 280(40.0%) specimens. G and P genotyping was performed among the 46 representative positive specimens, 20(43.5%) were emerging strain G9P[8], which were associated with VP6 genotype II (subgroup II), and NSP4 genotype B, followed by 16(34.8%) G2P[4], 8(17.4%) G1P[8] and 2(4.4%) G4P[8] strains. G9P[8] was found to be the most predominant strain in 2004, but the prevalence rate abruptly decreased during the period 2005-2006. In addition G2P[4] was the most prevalent strain in 2005 and 2006. G1P[8] was less prevalent in the study period then the previous years. Nucleotide Sequence identity of VP7 gene of G9 rotaviruses were higher than 99.4% with each other and all the G9 rotavirus strains in this study clustered in a single branch of the phylogenetic tree. Nucleotide sequence identity of complete VP4 gene of P[8] rotaviruses were more than 99.7% with each other and all the P[8] rotavirus strains in this study grouped in a single cluster suggesting recent emergence from a common ancestor. An important finding of this study is that the genetic profile of rotavirus is changing within very short period in Bangladesh and continued surveillance of the circulating strains is necessary to detect new strains or new variants which can escape immune protection induced by available vaccines.
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Genetic programming and feature selection for classification of breast masses in mammograms. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2008; 2006:3021-4. [PMID: 17945751 DOI: 10.1109/iembs.2006.260460] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A dataset of 57 breast mass mammographic images, each with 22 features computed, was used in this investigation. The extracted features relate to edge-sharpness, shape, and texture. The novelty of this paper is the adaptation and application of genetic programming (GP). To refine the pool of features available to the GP classifier, we used five feature-selection methods, including three statistical measures -- Student's t-test, Kolmogorov-Smirnov Test, and Kullback-Leibler Divergence. Both the training and test accuracies obtained were above 99.5% for training and typically above 98% for testing.
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Transport properties of CdS nanowire embedded poly(3-hexyl thiophene) nanocomposite. J Chem Phys 2006; 125:174717. [PMID: 17100471 DOI: 10.1063/1.2370928] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Electrical transport properties of CdS nanowire embedded regioregular poly(3-hexyl thiophene) (P3HT) nanocomposite are investigated and the results are compared with those of the pure P3HT polymer. Both dc and ac conductivities of P3HT and CdS-P3HT nanocomposites show semiconducting nature and conductivity of CdS-P3HT is much less than that of the pure P3HT conducting polymer. The difference in the electrical behavior is attributed to the formation of nanowires in the CdS-P3HT nanocomposite. The dc conductivity data at high and low temperatures are qualitatively consistent with the optical-photon-assisted hopping and variable-range hopping models, respectively. However, the multiphonon-assisted hopping models of small polarons in nonadiabatic regime, which consider strong interactions with electrons with the optical as well as acoustical phonons, are the best to interpret quantitatively the experimental data in the entire temperature range for both P3HT and CdS-P3HT nanocomposites. We observe that the quantum tunneling model of small polarons is consistent with almost every respect of the loss data of P3HT conducting polymer, while for CdS-P3HT nanocomposite the ac conductivity varies with temperature in a different manner, which is explained in terms of simple quantum tunneling model of electrons in contrast to that of pure P3HT conducting polymer.
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Classification of breast masses in mammograms using genetic programming and feature selection. Med Biol Eng Comput 2006; 44:683-94. [PMID: 16937210 DOI: 10.1007/s11517-006-0077-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Accepted: 05/12/2006] [Indexed: 10/24/2022]
Abstract
Mammography is a widely used screening tool and is the gold standard for the early detection of breast cancer. The classification of breast masses into the benign and malignant categories is an important problem in the area of computer-aided diagnosis of breast cancer. A small dataset of 57 breast mass images, each with 22 features computed, was used in this investigation; the same dataset has been previously used in other studies. The extracted features relate to edge-sharpness, shape, and texture. The novelty of this paper is the adaptation and application of the classification technique called genetic programming (GP), which possesses feature selection implicitly. To refine the pool of features available to the GP classifier, we used feature-selection methods, including the introduction of three statistical measures--Student's t test, Kolmogorov-Smirnov test, and Kullback-Leibler divergence. Both the training and test accuracies obtained were high: above 99.5% for training and typically above 98% for test experiments. A leave-one-out experiment showed 97.3% success in the classification of benign masses and 95.0% success in the classification of malignant tumors. A shape feature known as fractional concavity was found to be the most important among those tested, since it was automatically selected by the GP classifier in almost every experiment.
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Noninvasive fetal electrocardiogram extraction: blind separation versus adaptive noise cancellation. IEEE Trans Biomed Eng 2001; 48:12-8. [PMID: 11235584 DOI: 10.1109/10.900244] [Citation(s) in RCA: 200] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The problem of the fetal electrocardiogram (FECG) extraction from maternal skin electrode measurements can be modeled from the perspective of blind source separation (BSS). Since no comparison between BSS techniques and other signal processing methods has been made, we compare a BSS procedure based on higher-order statistics and Widrow's multireference adaptive noise cancelling approach. As a best-case scenario for this latter method, optimal Wiener-Hopf solutions are considered. Both procedures are applied to real multichannel ECG recordings obtained from a pregnant woman. The experimental outcomes demonstrate the more robust performance of the blind technique and, in turn, verify the validity of the BSS model in this important biomedical application.
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A conserved function for Arabidopsis SUPERMAN in regulating floral-whorl cell proliferation in rice, a monocotyledonous plant. Curr Biol 2000; 10:215-8. [PMID: 10704413 DOI: 10.1016/s0960-9822(00)00341-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Studies of floral organ development in two dicotyledonous plants, Arabidopsis thaliana and Antirrhinum majus, have shown that three sets of genes (A, B and C) can pattern sepals, petals, stamens and carpels [1] [2]. Mechanisms that define boundaries between these floral whorls are unclear, however. The Arabidopsis gene SUPERMAN (SUP), which encodes a putative transcription factor, maintains the boundary between stamens and carpels [3] [4] [5], possibly by regulating cell proliferation. By overexpressing SUP cDNA in rice, we examined whether its effects on whorl boundaries are conserved in a divergent monocotyledonous species. High-level ectopic SUP expression in transgenic rice resulted in juvenile death or dwarf plants with decreased axillary growth. Plants with lower levels of SUP RNA were vegetatively normal, but the flowers showed ubiquitous ventral carpel expansion. This was often coupled with reduced stamen number, or occurrence of third-whorl stamen-carpel mosaic organs. Additionally, proliferation of second-whorl ventral cells produced adventitious lodicules, and flowers lost the asymmetry that is normally inherent to this whorl. We predict that SUP is a conserved regulator of floral whorl boundaries and that it affects cell proliferation.
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Maternal and foetal ECG separation using blind source separation methods. IMA JOURNAL OF MATHEMATICS APPLIED IN MEDICINE AND BIOLOGY 1997; 14:207-25. [PMID: 9306675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The separation of the maternal and foetal electrocardiograms (ECGs) from skin electrodes located on the mother's body may be modelled as a blind source separation (BSS) problem. This consists in the reconstruction of a set of unknown mutually independent source signals from the sole knowledge of another set of linear mixtures of the sources, where the mixture pattern is also unknown. Three BSS methods based on cumulants are considered: principal-component analysis (PCA), higher-order singular-value decomposition (HOSVD), and higher-order eigenvalue decomposition (HOEVD). All these methods are applied to the foetal-ECG extraction problem by using real ECG data. The last two methods appear to provide a more satisfactory separation than the first method, with HOEVD offering slightly better results.
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Generation of a nested series of interstitial deletions in yeast artificial chromosomes carrying human DNA. Proc Natl Acad Sci U S A 1991; 88:5744-8. [PMID: 2062854 PMCID: PMC51954 DOI: 10.1073/pnas.88.13.5744] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We have generated a nested series of interstitial deletions in a fragment of human X chromosome-derived DNA cloned into a yeast artificial chromosome (YAC) vector. A yeast strain carrying the YAC was transformed with a linear recombination substrate containing at one end a sequence that is uniquely represented on the YAC and at the other end a truncated long interspersed repetitive element (LINE 1, or L1). Homologous recombination between the YAC and the input DNA resulted in a nested series of interstitial deletions, the largest of which was 500 kilobases. In combination with terminal deletions that can be generated through homologous recombination, the interstitial deletions are useful for mapping and studying gene structure-function relationships.
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Maternal mortality. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1990; 88:249-50. [PMID: 2286757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Maternal mortality in Chittaranjan Seva Sadan, Calcutta, in 1983, 1985 and 1986 was 2.45, 3.01 and 2.8 per thousand respectively. Abortion contributed a little in 1983 and 1985, whereas it was 15.7% in 1986. Haemorrhage was the commonest single cause of death in 1983 (28%) and 1985 (21.4%) as opposed to eclampsia in 1986 (28.9%). Infective hepatitis during pregnancy and labour was the commonest indirect cause of maternal mortality followed by anaemia. Usual difficulties like lack of antenatal care, multiparity, low socio-economical status, illiteracy, etc, in populated developing countries are responsible for this sad state of affairs in this country as well.
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Cord prolapse: a challenge to the obstetrician. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1988; 86:206-8. [PMID: 3230320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Regulated expression of genes inserted at the human chromosomal beta-globin locus by homologous recombination. Proc Natl Acad Sci U S A 1988; 85:3845-9. [PMID: 3375244 PMCID: PMC280316 DOI: 10.1073/pnas.85.11.3845] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We have examined the effect of the site of integration on the expression of cloned genes introduced into cultured erythroid cells. Smithies et al. [Smithies, O., Gregg, R.G., Boggs, S.S., Koralewski, M.A. & Kucherlapati, R.S. (1985) Nature (London) 317, 230-234] reported the targeted integration of DNA into the human beta-globin locus on chromosome 11 in a mouse erythroleukemia-human cell hybrid. These hybrid cells can undergo erythroid differentiation leading to greatly increased mouse and human beta-globin synthesis. By transfection of these hybrid cells with a plasmid carrying a modified human beta-globin gene and a foreign gene composed of the coding sequence of the bacterial neomycin-resistance gene linked to simian virus 40 transcription signals (SVneo), cells were obtained in which the two genes are integrated at the beta-globin locus on human chromosome 11 or at random sites. When we examined the response of the integrated genes to cell differentiation, we found that the genes inserted at the beta-globin locus were induced during differentiation, whereas randomly positioned copies were not induced. Even the foreign SVneo gene was inducible when it had been integrated at the beta-globin locus. The results show that genes introduced at the beta-globin locus acquire some of the regulatory properties of globin genes during erythroid differentiation.
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Structure of nucleohistone & nucleoprotamine--a comparative study. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 1983; 20:74-9. [PMID: 6671666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Activity of Japanese encephalitis virus among certain domestic animals in West Bengal. Indian J Med Res 1982; 76:499-503. [PMID: 6295928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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