Evaluation of Rapid Extraction Methods Coupled with a Recombinase Polymerase Amplification Assay for Point-of-Need Diagnosis of Post-Kala-Azar Dermal Leishmaniasis

To detect Post-kala-azar leishmaniasis (PKDL) cases, several molecular methods with promising diagnostic efficacy have been developed that involve complicated and expensive DNA extraction methods, thus limiting their application in resource-poor settings. As an alternative, we evaluated two rapid DNA extraction methods and determined their impact on the detection of the parasite DNA using our newly developed recombinase polymerase amplification (RPA) assay. Skin samples were collected from suspected PKDL cases following their diagnosis through national guidelines. The extracted DNA from three skin biopsy samples using three different extraction methods was subjected to RPA and qPCR. The qPCR and RPA assays exhibited highest sensitivities when reference DNA extraction method using Qiagen (Q) kit was followed. In contrast, the sensitivity of the RPA assay dropped to 76.7% and 63.3%, respectively, when the boil & spin (B&S) and SpeedXtract (SE) rapid extraction methods were performed. Despite this compromised sensitivity, the B&S-RPA technique yielded an excellent agreement with both Q-qPCR (k = 0.828) and Q-RPA (k = 0.831) techniques. As expected, the reference DNA extraction method was found to be superior in terms of diagnostic efficacy. Finally, to apply the rapid DNA extraction methods in resource-constrained settings, further methodological refinement is warranted to improve DNA yield and purity through rigorous experiments

Characterization of Dynamic Elastic Modulus and Damping Property of CNx Coating Material by Experimental Modal Analysis and Finite Element Approach

Free-layer hard or soft coating material can be used for enhancing the inherent damping capacity (energy dissipation ability) of a structure under cyclic bending deformation. This may help to attenuate the vibration amplitude at the resonance frequency. In this study, dynamic mechanical and damping properties of a carbon based (CNx) coating material have been investigated. For determining the material properties of this coating, two samples (600 μm and 800 μm thick carbon nitride (CNx) film layers) were produced and deposited onto two internal turning tools by using the plasma enhanced chemical vapor deposition (PECVD) process. The deposition process was conducted at the room temperature with the magnetron sputtering of a copper and a subsequent graphite target plate in a highly ionized plasma and reactive environment of Ar, N2 and C2H2 gases. Eigen frequencies and system loss factors of the uncoated and coated tools were extracted, for the first two fundamental bending modes (mode X and mode Y), from the ‘drive point’ measurements of free hanging impact tests at the free-free boundary condition. Modulus of elasticity and loss factor of the coating material has been deduced through the comparison between the eigen frequencies and resonance amplitudes of the identical bending modes extracted from the experimental and analytical frequency response functions. The results obtained from the experimental modal analyses and the iterative finite element analyses show that, compared to the substrate, the flexural stiffness and the damping capacity of the coated tools have increased notably. The resonant frequencies of the coated samples have been shifted to the higher frequency levels, and the frequency response acceleration amplitudes have been attenuated dramatically. Elastic modulus and loss factor range of the coating material have been found to be in the range of 32.5 GPa to 49.1 GPa and 0.004 to 0.0245 respectively. Comparison between the analytical frequency response functions of the CNx coating material and 3M-112 viscoelastic material coated samples (for 800 μm film thickness) has anticipated that the coating material has higher loss modulus (energy dissipation ability) as opposed to the viscoelastic material. Scanning electron microscope images of the cross-section of a coated sample have revealed that the frictional energy losses between the interfaces of the carbon-nitride columnar micro-structures dominate the inherent damping mechanism of the coating material. Voids and porosities, present between the columnar clusters, further increase the energy dissipation ability of the coating material by enhancing the interface slippage mechanism during the cyclic bending deformation

Anti-Corruption Disclosure, Corporate Social Expenditure and Political Corporate Social Responsibility: Empirical Evidence from Bangladesh

Corruption is a major concern globally, particularly in developing countries, such as Bangladesh, where it is the main obstacle to economic development. Corruption is also mentioned as the major impediment to accomplishing sustainable development. There is a dearth of studies on anti-corruption disclosure (ACD), political corporate social responsibility (PCSR), and cash holding in Bangladesh magnitude of this research. This study investigates different drivers and motivations of ACD practice of a less control of corruption country’s firm-level observations. This study incorporates an institutional and legitimacy theoretical lens to explain anti-corruption disclosure practice. In order to draw the best picture of corruption disclosure, the study uses all financial sector companies listed on the Dhaka Stock Exchange. Therefore, the total firm-year observations are 245 from 2012–2016. The authors developed a diverse set of 97 keywords as content for ACD. The regression results show that CSR expenditures, political corporate social responsibility (PCSR), financial constraint, internationalization of reporting, and media visibility positively and significantly affect firm-level ACD. Furthermore, cash holdings show negative and significant relationships. The study provides new evidence on CSR expenditure, PCSR, cash holdings, and media visibility from a developing country’s perspective. Therefore, the results suggest that policymakers and regulatory authorities can deal with ACD as a legitimization tool for society and stakeholders

The Usefulness of Cell Phones for Crop Farmers in Selected Regions of Bangladesh

This research endeavours the usefulness of cell phones for crop farmers in selected region of Bangladesh. For adequate findings and to achieve its purpose, structured interview schedule was adopted to collect data from 281 randomly selected farmers and it was revealed that a little over 60% of them found cell phones very useful, while only 5.3% respondents found the cell phone as less useful. Based on average talk time hours spend in the last six months, top three sources of agricultural information were friends and relatives, distributors and middlemen, and farmers in advanced categories. The results of the ordered logit model showed that their usefulness was significantly determined by age, farm size, per month call charges, and experience in using cell phones. Higher call rates, lack of awareness and paucity of mobile-based information sources were major bottlenecks in using cell phones for agricultural information. The recommendations suggested therein lead to connecting farmers with reliable and rich information sources, use of MMS and SMS, voice call activities, providing subsidized SIM cards, and ultimately undertake widespread campaigns for training of aged farmers to persuade their interest towards the use of cell phones and mobile-based information sources

The Usefulness of Cell Phones for Crop Farmers in Selected Regions of Bangladesh

This research endeavours the usefulness of cell phones for crop farmers in selected region of Bangladesh. For adequate findings and to achieve its purpose, structured interview schedule was adopted to collect data from 281 randomly selected farmers and it was revealed that a little over 60% of them found cell phones very useful, while only 5.3% respondents found the cell phone as less useful. Based on average talk time hours spend in the last six months, top three sources of agricultural information were friends and relatives, distributors and middlemen, and farmers in advanced categories. The results of the ordered logit model showed that their usefulness was significantly determined by age, farm size, per month call charges, and experience in using cell phones. Higher call rates, lack of awareness and paucity of mobile-based information sources were major bottlenecks in using cell phones for agricultural information. The recommendations suggested therein lead to connecting farmers with reliable and rich information sources, use of MMS and SMS, voice call activities, providing subsidized SIM cards, and ultimately undertake widespread campaigns for training of aged farmers to persuade their interest towards the use of cell phones and mobile-based information sources

High dynamic stiffness mechanical structures with nanostructured composite coatings deposited by high power impulse magnetron sputtering

Nanostructured Cu:CuCNx composite coatings with high static and dynamic stiffness were synthesized by means of plasma-enhanced chemical vapor deposition (PECVD) combined with high power impulse magnetron sputtering (HiPIMS). Scanning electron microscope (SEM) images and energy-dispersive X-ray spectroscopy (EDS) mapping from cross-sectioned samples reveals a multi-layered nanostructure enriched in Cu, C, N, and O in different ratios. Mechanical properties of the coatings were investigated by Vickers micro-indention and model tests. It was observed that copper inclusions as well as copper interlayers in the CNx matrix can increase mechanical damping by up to 160%. Mechanical properties such as hardness, elastic modulus and loss factor were significantly improved by increasing the discharge power of the sputtering process. Moreover the coatings loss modulus was evaluated on the basis of indentation creep measurements under room temperature. The coating with optimum properties exhibited loss modulus of 2.6 GPa. The composite with the highest damping loss modulus were applied on the clamping region of a milling machining tool to verify their effect in suppressing regenerative tool chatter. The high dynamic stiffness coatings were found to effectively improve the critical stability limit of a milling tool by at least 300%, suggesting a significant increase of the dynamic stiffness.QC 20160209HiPPOCAM

Revisiting the diagnosis and treatment of Para Kala-azar Dermal Leishmaniasis in the endemic foci of Bangladesh.

Para Kala-azar Dermal Leishmaniasis (Para-KDL) manifests the concomitant presence of Post Kala-azar Dermal Leishmaniasis and Visceral Leishmaniasis and works as a reservoir of infection. The study discusses the cases and their management and aims to address the gaps within existing methods of diagnosis and treatment. This retrospective cross-sectional study discusses 16 Para-KDL cases with one-year follow-up data, treated between 2012-2021 at the Surya Kanta Kala-azar Research Center, Bangladesh. We collected data from hospital records and used STATA 16 to analyze and see the frequency distribution and variable means. We found five patients without any history of kala-azar infection. All the patients were treated with 20 mg/kg Liposomal Amphotericin B in 4 divided doses except one with a history of AmBisome hypersensitivity. One year after treatment, all patients were free from skin lesions, with no hepatosplenomegaly, and observed significant improvement in BMI and hemoglobin levels. The Para-KDL patients are challenging to diagnose, and the relapse and treatment failure leishmania patients might have belonged to this rare group, contributing to their poor prognosis. Therefore, developing an appropriate diagnostic workflow and a new drug regimen is essential to sustain the success of our elimination efforts

Evaluation of Rapid Extraction Methods Coupled with a Recombinase Polymerase Amplification Assay for Point-of-Need Diagnosis of Post-Kala-Azar Dermal Leishmaniasis

To detect Post-kala-azar leishmaniasis (PKDL) cases, several molecular methods with promising diagnostic efficacy have been developed that involve complicated and expensive DNA extraction methods, thus limiting their application in resource-poor settings. As an alternative, we evaluated two rapid DNA extraction methods and determined their impact on the detection of the parasite DNA using our newly developed recombinase polymerase amplification (RPA) assay. Skin samples were collected from suspected PKDL cases following their diagnosis through national guidelines. The extracted DNA from three skin biopsy samples using three different extraction methods was subjected to RPA and qPCR. The qPCR and RPA assays exhibited highest sensitivities when reference DNA extraction method using Qiagen (Q) kit was followed. In contrast, the sensitivity of the RPA assay dropped to 76.7% and 63.3%, respectively, when the boil & spin (B&S) and SpeedXtract (SE) rapid extraction methods were performed. Despite this compromised sensitivity, the B&S-RPA technique yielded an excellent agreement with both Q-qPCR (k = 0.828) and Q-RPA (k = 0.831) techniques. As expected, the reference DNA extraction method was found to be superior in terms of diagnostic efficacy. Finally, to apply the rapid DNA extraction methods in resource-constrained settings, further methodological refinement is warranted to improve DNA yield and purity through rigorous experiments

Evaluation of Rapid Extraction Methods Coupled with a Recombinase Polymerase Amplification Assay for Point-of-Need Diagnosis of Post-Kala-Azar Dermal Leishmaniasis

To detect Post-kala-azar leishmaniasis (PKDL) cases, several molecular methods with promising diagnostic efficacy have been developed that involve complicated and expensive DNA extraction methods, thus limiting their application in resource-poor settings. As an alternative, we evaluated two rapid DNA extraction methods and determined their impact on the detection of the parasite DNA using our newly developed recombinase polymerase amplification (RPA) assay. Skin samples were collected from suspected PKDL cases following their diagnosis through national guidelines. The extracted DNA from three skin biopsy samples using three different extraction methods was subjected to RPA and qPCR. The qPCR and RPA assays exhibited highest sensitivities when reference DNA extraction method using Qiagen (Q) kit was followed. In contrast, the sensitivity of the RPA assay dropped to 76.7% and 63.3%, respectively, when the boil & spin (B&S) and SpeedXtract (SE) rapid extraction methods were performed. Despite this compromised sensitivity, the B&S-RPA technique yielded an excellent agreement with both Q-qPCR (k = 0.828) and Q-RPA (k = 0.831) techniques. As expected, the reference DNA extraction method was found to be superior in terms of diagnostic efficacy. Finally, to apply the rapid DNA extraction methods in resource-constrained settings, further methodological refinement is warranted to improve DNA yield and purity through rigorous experiments

Cigarette smoking and associated factors among men in five South Asian countries: A pooled analysis of nationally representative surveys

Smoking is one of the leading causes of premature deaths worldwide. The cigarette is the commonest form of tobacco smoking. This study investigated the factors associated with cigarette smoking among men in five South Asian countries. We analyzed nationally representative cross-sectional study (Demographic and Health Survey) data conducted in Afghanistan, India, Maldives, Nepal, and Pakistan from 2015–2018. Our study population was men aged between 15 and 49 years. The outcome variable was the prevalence of cigarette smoking. We performed both pooled and country-specific analyses using multivariable logistic regression. The prevalence of cigarette smoking among men is the highest (41.2%) in the Maldives and the lowest (20.1%) in Pakistan. Our pooled analysis found that higher age, lower education, lower wealth status, and involvement in any occupations were strongly associated with cigarette smoking (p-value <0.001). However, we did not find a significant association between age and wealth status in Afghanistan, occupations in Nepal and Pakistan, and education in Pakistan with cigarette smoking when country-specific analyses were performed. In this study, socioeconomic position, age, and urban area are strongly associated with cigarette smoking in South Asian countries. The country-specific circumstances should be considered in planning and designing national smoking control strategies and interventions. However, improving access to smoking cessation services could be an effective intervention for all studied countries, Afghanistan, India, Maldives, Nepal, and Pakistan