Graphene quantum dot modified screen printed immunosensor for the determination of parathion

Mehta, J.,Bhardwaj, N.,Bhardwaj, S.K.,Tuteja, S.K.,Vinayak, P.,Paul, A.K.,Kim, K.H.,Deep, A. Academic Press 2017 Analytical biochemistry Vol.523 No.-

<P>The widespread use of pesticides has immense effect on increased crop productions. However, they are also responsible for posing detrimental health hazards and/or for contaminating the environment with chemical residues. A routine and an on-field detection of pesticide residues in different food, water, and soil samples has become a need of the hour for which biosensors can offer a viable alternative. The present work reports a functionalized graphene quantum dot (GQD) based screen printed electro-chemical immunosensor for the detection of parathion. The application of GQDs has permitted the realization of a sensitive, robust, and reproducible sensor unlike those carried out earlier for the similar purposes. This immunosensor exhibited a dynamic linear response for parathion within the range of 0.01 -10(6) ng/L with a very low detection limit of 46 pg/L. According to the analysis of potential interferences, the proposed sensor was specifically detecting parathion even in the presence of its metabolite, paraoxon. The investigations of the proposed sensing approach with respect to stability, response reproducibility, and regeneration have fully supported its potential practical applicability. (C) 2017 Elsevier Inc. All rights reserved.</P>

Effect of Heat-Treatment on the Microstructure, Mechanical Properties and Corrosion Behaviour of SS 316 Structures Built by Laser Directed Energy Deposition Based Additive Manufacturing

K. Benarji,Y. Ravi Kumar,A. N. Jinoop,C. P. Paul,K. S. Bindra 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

This paper reports investigation on the effect of heat-treatment on the microstructure, mechanical, tribological and corrosioncharacteristics of laser directed energy deposition (LDED) built stainless steel (SS 316) bulk structures. LDED built SS316 structures are subjected to solution treatment at 1073 K (HT1073) and 1273 K (HT1273) and reduction in ferrite phasewith heat-treatment is observed from microstructure. X-ray diffraction and microstructure shows that the austenite phaseis observed at all conditions and reducing ferrite phase intensity is noticed with an increase in heat-treatment temperature. Improvement in the plasticity retaining capacity and reduction in micro-hardness by 72.8% and 6.75% are noticed withheat-treatment, respectively. It is observed that the corrosion rate and specific wear rate increases after heat-treatment. Themaximum specific wear rate of 0.19375 × 10–4 mm3/min is observed in the HT1273 sample with wide and deep groovesnoticed on the worn out surface of heat-treated samples. The SEM images of wear track is characterized with abrasive wearmechanism for as-built sample, while heat-treated samples shows plastic deformation, followed by spalling effect. The workpaves a way to understand the effect of heat-treatment on LDED built SS 316 bulk structures.

Characterization of macro-benthic fauna for ecological health status of the Fosu and Benya lagoons in coastal Ghana

Frederick A. Armah,Benjamin Ason,Isaac Luginaah,Paul K. Essandoh 한국생태학회 2012 Journal of Ecology and Environment Vol.35 No.4

This study conducted a comparative analysis of benthic macroinvertebrate communities in the Fosu and Benya lagoons in Ghana, based on the anthropogenic effect on the two lagoons. Salinity, oxygen, temperature, conductivity, turbidity and pH were measured, invertebrate richness and species densities were determined. The AZTI Marine Biotic Index (AMBI) and multivariate statistics were used to determine the different responses of fauna to pollution. The fauna were categorized into five ecological groups based on the degree of tolerance of the different species to pollution: disturbancesensitive species; disturbance-indifferent species, disturbance-tolerant species, second-order opportunistic species; and first-order opportunistic species. The Fosu Lagoon supported more pollution tolerant species, whereas the Benya Lagoon had more species that were sensitive to organic enrichment under relatively unpolluted conditions. Chironomus sp.,which is adapted to virtually anoxic conditions, was the most abundant in the Fosu Lagoon whereas Nemertea sp. was the most abundant in the Benya Lagoon. The numerical and relative abundance (%) of all 7 taxa in the Fosu Lagoon was 1,359 and 92.35%, respectively. The numerical and relative abundance (%) of all 34 taxa in the Benya Lagoon was 2,459and 87.52%, respectively. Expectedly, the level of dissolved oxygen in the less saline Fosu Lagoon was higher than that in the more saline Benya Lagoon. The reduced photoperiod and photosynthetic activities of aquatic plants might account for this trend. There is a need to implement comprehensive monitoring and management initiatives for sustaining the ecological health of coastal lagoons in Ghana in order to support the many people that depend upon these ecosystems for their livelihood.

Abrupt reversal in emissions and atmospheric abundance of HCFC-133a (CF₃ CH₂ Cl) : HCFC-133A REVERSAL

Vollmer, Martin K.,Rigby, Matt,Laube, Johannes C.,Henne, Stephan,Rhee, Tae Siek,Gooch, Lauren J.,Wenger, Angelina,Young, Dickon,Steele, L. Paul,Langenfelds, Ray L.,Brenninkmeijer, Carl A. M.,Wang, Jia American Geophysical Union 2015 Geophysical Research Letters Vol.42 No.20

Optimal control strategy to combat the spread of COVID-19 in absence of effective vaccine

M.H.A. Biswas,M.S. Khatun,M.A. Islam,S. Mandal,A.K. Paul,A. Ali 한국전산응용수학회 2022 Journal of applied mathematics & informatics Vol.40 No.3

Many regions of the world are now facing the second wave of boomed cases of COVID-19. This time, the second wave of this highly infectious disease (COVID-19) is becoming more devastating. To control the existing situation, more mass testing, and tracing of COVID-19 positive individuals are required. Furthermore, practicing to wear a face mask and maintenance of physical distancing are strongly recommended for everyone. Taking all these into consideration, an optimal control problem has been reformulated in terms of nonlinear ordinary differential equations in this paper. The aim of this study is to explore the control strategy of coronavirus-2 disease (COVID-19) and thus, minimize the number of symptomatic, asymptomatic and infected individuals as well as cost of the controls measures. The optimal control model has been analyzed analytically with the help of the necessary conditions of very well-known Pontryagin’s maximum principle. Numerical simulations of the optimal control problem are also performed to illustrate the results.

Genetic Trend for Growth in a Closed Indian Herd of Landrace × Desi Crossbreds

Gaur, G.K.,Ahlawat, S.P.S.,Chhabra, A.K.,Paul, Satya Asian Australasian Association of Animal Productio 1998 Animal Bioscience Vol.11 No.4

This study has objectives of to estimate the genetic and phenotypic trend for growth in a closed herd of Landrace $\times$ desi crossbreds. The possibility of early selection of boars was also investigated in order to reduce generation interval and thus, to enhance response per year in selection programmes. The data originated from Livestock Production Research (Pigs), Indian Veterinary Research Institute (IVRI), Izatnagar (UP), India - a unit of All India Coordinated research Project on Pigs (AICRP on Pigs). Data consisted of 891 crossbred piglets, progeny of 29 boars. The piglets were born in 132 parities of 72 sows between 8 years from 1987 to 1994. Records on weight at birth, at 2 weeks interval upto 8 weeks of age (Wl, W2, ${\cdots}\;{\cdots}$ W8) and at 16th week (W16) were used in this investigation. BLLTP estimates of the sires were computed. Breeding value of each sire was estimated as twice of sire and sire group solutions. Phenotypic trend was estimated as regression of weight performance on year. Genetic trend was computed by estimating regression of breeding value of sires on time. Average body weights ranged from 0.92 kg (W1) to 18.95 kg (W16) and showed a continuous increase over age. Heritabilities of the weight at 4th and 6th week were medium (0.29 and 0.14). Rest of the weights were highly heritable. The product moment and rank, both correlations were high between breeding value for W6 and W16 (0.68 and 0.70). This shows that sire selection for W6 can be successfully implemented in order to achieve sufficient genetic improvement in growth. Phenotypic trend was positive at all ages. The phenotypic regression coefficient ranged from 0.02 kg at birth to 0.40 kg at 16 weeks. Genetic trend was also positive. The regression coefficients of average breeding value of sires on time showed a range of 1.471 kg (0.021 to 1.492 kg) for different weights. These coefficients were significant and higher than their corresponding phenotypic regression coefficient.

SYSTEM OF HOMOGENEOUS DIFFERENTIAL EQUATION AT INFINITY

Das P. K.,Mohanta S. K.,Paul A. K. 경남대학교 수학교육과 2019 Nonlinear Functional Analysis and Applications Vol.24 No.1

The main purpose of this paper is to study about the existence and uniqueness of a solution of a system of differential equation obtained from a new class of second order differential equation at infinity. To solve the problem, first we develop a system of differential equation and then obtain the general solution of the same with some conditions.

Molecular Surveillance Identifies Multiple Transmissions of Typhoid in West Africa

Wong, Vanessa K.,Holt, Kathryn E.,Okoro, Chinyere,Baker, Stephen,Pickard, Derek J.,Marks, Florian,Page, Andrew J.,Olanipekun, Grace,Munir, Huda,Alter, Roxanne,Fey, Paul D.,Feasey, Nicholas A.,Weill, F Public Library of Science 2016 PLoS neglected tropical diseases Vol.10 No.9

<▼1><P><B>Background</B></P><P>The burden of typhoid in sub-Saharan African (SSA) countries has been difficult to estimate, in part, due to suboptimal laboratory diagnostics. However, surveillance blood cultures at two sites in Nigeria have identified typhoid associated with <I>Salmonella enterica</I> serovar Typhi (<I>S</I>. Typhi) as an important cause of bacteremia in children.</P><P><B>Methods</B></P><P>A total of 128 <I>S</I>. Typhi isolates from these studies in Nigeria were whole-genome sequenced, and the resulting data was used to place these Nigerian isolates into a worldwide context based on their phylogeny and carriage of molecular determinants of antibiotic resistance.</P><P><B>Results</B></P><P>Several distinct <I>S</I>. Typhi genotypes were identified in Nigeria that were related to other clusters of <I>S</I>. Typhi isolates from north, west and central regions of Africa. The rapidly expanding <I>S</I>. Typhi clade 4.3.1 (H58) previously associated with multiple antimicrobial resistances in Asia and in east, central and southern Africa, was not detected in this study. However, antimicrobial resistance was common amongst the Nigerian isolates and was associated with several plasmids, including the IncHI1 plasmid commonly associated with <I>S</I>. Typhi.</P><P><B>Conclusions</B></P><P>These data indicate that typhoid in Nigeria was established through multiple independent introductions into the country, with evidence of regional spread. MDR typhoid appears to be evolving independently of the haplotype H58 found in other typhoid endemic countries. This study highlights an urgent need for routine surveillance to monitor the epidemiology of typhoid and evolution of antimicrobial resistance within the bacterial population as a means to facilitate public health interventions to reduce the substantial morbidity and mortality of typhoid.</P></▼1><▼2><P><B>Author Summary</B></P><P>Typhoid fever, a serious bloodstream infection caused by the bacterium <I>Salmonella</I> Typhi, is a major cause of disease and death around the world. There have been limited data on the epidemiology of typhoid in many countries in sub-Saharan African, including Nigeria. Recent evidence, however, showed that typhoid was an important cause of bacteraemia in children residing in two regions of Nigeria. Here, we analyzed the whole genome sequences of 128 <I>S</I>. Typhi isolates from two studies in order to elucidate the population structure and characterize the genetic components of antimicrobial resistance. We found that the multiple <I>S</I>. Typhi genotypes identified were closely related to other <I>S</I>. Typhi from neighboring regions of Africa and that multidrug resistance (MDR) was common among these isolates, and in many cases was associated with the IncHI1 plasmid known to cause MDR typhoid. These results provide evidence that typhoid was established in Nigeria as a result of several independent introductions into the country and that there has been extensive exchange of <I>S</I>. Typhi in and around the region of West Africa. This study emphasizes the importance of surveillance to improve our understanding of the epidemiology of typhoid, which is needed to underpin public health measures to reduce the spread of disease and facilitate patient management.</P></▼2>

Characterization of macro-benthic fauna for ecological health status of the Fosu and Benya lagoons in coastal Ghana

Armah, Frederick A.,Ason, Benjamin,Luginaah, Isaac,Essandoh, Paul K. The Ecological Society of Korea 2012 Journal of Ecology and Environment Vol.35 No.4

This study conducted a comparative analysis of benthic macroinvertebrate communities in the Fosu and Benya lagoons in Ghana, based on the anthropogenic effect on the two lagoons. Salinity, oxygen, temperature, conductivity, turbidity and pH were measured, invertebrate richness and species densities were determined. The AZTI Marine Biotic Index (AMBI) and multivariate statistics were used to determine the different responses of fauna to pollution. The fauna were categorized into five ecological groups based on the degree of tolerance of the different species to pollution: disturbance-sensitive species; disturbance-indifferent species, disturbance-tolerant species, second-order opportunistic species; and first-order opportunistic species. The Fosu Lagoon supported more pollution tolerant species, whereas the Benya Lagoon had more species that were sensitive to organic enrichment under relatively unpolluted conditions. Chironomus sp., which is adapted to virtually anoxic conditions, was the most abundant in the Fosu Lagoon whereas Nemertea sp. was the most abundant in the Benya Lagoon. The numerical and relative abundance (%) of all 7 taxa in the Fosu Lagoon was 1,359 and 92.35%, respectively. The numerical and relative abundance (%) of all 34 taxa in the Benya Lagoon was 2,459 and 87.52%, respectively. Expectedly, the level of dissolved oxygen in the less saline Fosu Lagoon was higher than that in the more saline Benya Lagoon. The reduced photoperiod and photosynthetic activities of aquatic plants might account for this trend. There is a need to implement comprehensive monitoring and management initiatives for sustaining the ecological health of coastal lagoons in Ghana in order to support the many people that depend upon these ecosystems for their livelihood.

Prototype electrochromic device and dye sensitized solar cell using spray deposited undoped and 'Li' doped V₂O₅ thin film electrodes

Kovendhan, M.,Paul Joseph, D.,Manimuthu, P.,Sendilkumar, A.,Karthick, S.N.,Sambasivam, S.,Vijayarangamuthu, K.,Kim, H.J.,Choi, B.C.,Asokan, K.,Venkateswaran, C.,Mohan, R. Elsevier 2015 CURRENT APPLIED PHYSICS Vol.15 No.5

Lithium (Li) (0-5 wt%) doped V<SUB>2</SUB>O<SUB>5</SUB> thin films were spray deposited at 450 <SUP>o</SUP>C onto ITO substrates. Structural analysis using X-ray diffraction and Raman spectroscopy revealed orthorhombic phase of the films. In addition to the V<SUB>2</SUB>O<SUB>5</SUB> phase, presence of VO<SUB>2</SUB> peaks due to high deposition temperature is also evident from structural and optical characterization. The non-stoichiometric nature of the films due to loss of the terminal O atom was confirmed from Raman spectroscopy. The direct band gap, indirect bandgap, and phonon energies were also calculated from optical studies. Different charge states of vanadium ions present in the film were identified from X-ray photoelectron spectroscopy study. Results from cyclic voltammetry experiments reflected significant differences between the undoped and Li doped V<SUB>2</SUB>O<SUB>5</SUB> samples. Transport properties by Hall-effect measured at room temperature indicated significant increase in conductivity, carrier concentration and mobility of V<SUB>2</SUB>O<SUB>5</SUB> thin films on doping with Li. A Dye Sensitized Solar Cell (DSSC) was fabricated using mobility enhanced 5 wt% Li doped V<SUB>2</SUB>O<SUB>5</SUB> film as photoanode and its efficiency was found to be 2.7%. A simple electrochromic cell is fabricated using undoped V<SUB>2</SUB>O<SUB>5</SUB> thin film to demonstrate the colour change.