56 results on '"Rajarathinam R"'
Search Results
2. Automated Sentiment Analysis Using Deep Learning Artificial Neural Network for Scholars Digital Database Protection
- Author
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Rajarathinam, R., primary and Latha, R., additional
- Published
- 2019
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3. Automated Sentiment Analysis using Deep Learning Artificial Neural Network for Scholars Digital Database Protection.
- Author
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Rajarathinam, R. and Latha, R.
- Subjects
ARTIFICIAL neural networks ,ELECTRONIC journals ,SENTIMENT analysis ,BIBLIOGRAPHIC databases ,DEEP learning - Abstract
Article and journal publications are the important criteria for the researchers from different domains. The digital publications are basic proof for the scholars and for them to do research and development through academics and industrial applications. These scientific publication database should be copyrighted to the concern person those published the journals. The international journal publishers should provide the confidential of digital data citation in the form of text, diagram, literatures and coding using different languages to stop the forgeries by extracting and using others digital data without any authentication from the ownership. Much application software is available to prevent from the forgeries to stop digital malpractice. But still it is challenging to prevent entirely from forgeries, particularly on sentiment analysis from web-mining. An artificial intelligence (AI) is emerging technology in software industry and becoming very popular for different applications like web-mining. The Artificial Neural Network (ANN) can be proposed for sentiment analysis in web-mining content and meaning based retrieval on web database to prevent inconsistencies forgeries. The ANN is the most accurate tool to examine the content of the literature is original and its uniqueness. Also, proposing the concept of ANN to monitor the journal publishers for them while issuing the priority on indexing to the scholars and researchers by comparing the citation. The ANN is used to monitor the journals publications and indexing in the procedure of first come first out (FIFO) model. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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4. A case of mouth rot and helminthiasis in a Spectacled Cobra Naja naja
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Jayathangaraj, M.G., primary, Ramesh, S., additional, Basith, S. Abdul, additional, and Rajarathinam, R., additional
- Published
- 2005
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5. Chennai Snake Park: Environmental Orientation Programme for Teachers and Students on the Role of Reptiles.
- Author
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Rajarathinam, R., Gopalakrishnan, A. V., and Kalaiarasan, V.
- Published
- 2000
6. OBSERVATIONS ON THE BREEDING BEHAVIOUR OF THE MADRAS POND TORTOISE.
- Author
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Rathinasabapathy, B., Rajarathinam, R., and Kalaiarasan, V.
- Published
- 1993
7. Educational Poster on Common Venomous Snakes of India.
- Author
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Rajarathinam, R.
- Published
- 2000
8. Inverse design of chemoenzymatic epoxidation of soyabean oil through artificial intelligence-driven experimental approach.
- Author
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Sarmah N, Mehtab V, Borah K, Palanisamy A, Parthasarathy R, and Chenna S
- Subjects
- Soybean Oil chemistry, Hydrogen Peroxide chemistry, Enzymes, Immobilized metabolism, Enzymes, Immobilized chemistry, Fungal Proteins metabolism, Lipase metabolism, Artificial Intelligence, Epoxy Compounds chemistry
- Abstract
This paper presents an inverse design methodology that utilizes artificial intelligence (AI)-driven experiments to optimize the chemoenzymatic epoxidation of soyabean oil using hydrogen peroxide and lipase (Novozym 435). First, experiments are conducted using a systematic 3-level, 5-factor Box-Behnken design to explore the effect of input parameters on oxirane oxygen content (OOC (%)). Based on these experiments, various AI models are trained, with the support vector regression (SVR) model being found to be the most accurate. SVR is then used as a fitness function in particle swarm optimization, and the suggested optimal conditions, upon experimental validation, resulted in a maximum OOC of 7.19 % (∼98.5 % relative conversion of oil to epoxy). The results demonstrate the superiority of the proposed approach over existing methods. This framework offers a general intensified process optimization strategy with minimal resource utilization that can be applied to any other process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)
- Published
- 2024
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9. Interfacial Layer Materials with a Truxene Core for Dopant-Free NiO x -Based Inverted Perovskite Solar Cells.
- Author
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Ramanujam R, Hsu HL, Shi ZE, Lung CY, Lee CH, Wubie GZ, Chen CP, and Sun SS
- Abstract
Nickel oxide (NiO
x ) is commonly used as a holetransporting material (HTM) in p-i-n perovskite solar cells. However, the weak chemical interaction between the NiOx and CH3 NH3 PbI3 (MAPbI3 ) interface results in poor crystallinity, ineffective hole extraction, and enhanced carrier recombination, which are the leading causes for the limited stability and power conversion efficiency (PCE). Herein, two HTMs, TRUX-D1 (N2 ,N7 ,N12 -tris(9,9-dimethyl-9H-fluoren-2-yl)-5,5,10,10,15,15-hexaheptyl-N2 ,N7 ,N12 -tris(4-methoxyphenyl)-10,15-dihydro-5H-diindeno[1,2-a:1',2'-c]fluorene-2,7,12-triamine) and TRUX-D2 (5,5,10,10,15,15-hexaheptyl-N2 ,N7 ,N12 -tris(4-methoxyphenyl)-N2 ,N7 ,N12 -tris(10-methyl-10H-phenothiazin-3-yl)-10,15-dihydro-5H-diindeno[1,2-a:1',2'-c]fluorene-2,7,12-triamine), are designed with a rigid planar C3 symmetry truxene core integrated with electron-donating amino groups at peripheral positions. The TRUX-D molecules are employed as effective interfacial layer (IFL) materials between the NiOx and MAPbI3 interface. The incorporation of truxene-based IFLs improves the quality of perovskite crystallinity, minimizes nonradiative recombination, and accelerates charge extraction which has been confirmed by various characterization techniques. As a result, the TRUX-D1 exhibits a maximum PCE of up to 20.8% with an impressive long-term stability. The unencapsulated device retains 98% of their initial performance following 210 days of aging in a glove box and 75.5% for the device after 80 days under ambient air condition with humidity over 40% at 25 °C., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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10. Environmental impact assessment via life cycle analysis on ultrafiltration membrane fabricated from polyethylene terephthalate waste to treat microalgal cultivation wastewater for reusability.
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Rawindran H, Khoo KS, Ethiraj B, Lim JW, Liew CS, Goh PS, Raksasat R, Leong WH, Rajarathinam R, Ng HS, Tong WY, and Alam MM
- Subjects
- Waste Disposal, Fluid methods, Environment, Bioreactors, Recycling, Polyethylene Terephthalates chemistry, Microalgae growth & development, Ultrafiltration methods, Wastewater chemistry, Wastewater analysis, Membranes, Artificial
- Abstract
The current study had conducted the life cycle analysis (LCA) to assess the environmental impact of microalgal wastewater treatment via an integrated membrane bioreactor. The functional unit selected for this analysis was 1 kg of treated microalgal wastewater with contaminants eliminated by ultrafiltration membrane fabricated from recycled polyethylene terephthalate waste. Meanwhile, the applied system boundary in this study was distinguished based on two scenarios, namely, cradle-to-gate encompassed wastewater treatment only and cradle-to-cradle which included the reutilization of treated wastewater to cultivate microalgae again. The environmental impacts and hotspots associated with the different stages of the wastewater treatment process had clearly elucidated that membrane treatment had ensued the highest impact, followed by microalgal harvesting, and finally cultivation. Among the environmental impact categories, water-related impact was found to be prominent in the following series: freshwater ecotoxicity, freshwater eutrophication and marine ecotoxicity. Notably, the key performance indicator of all environmental impact, i.e., the global warming potential was found to be very much lower at 2.94 × 10
-4 kg CO2 eq as opposed to other literatures reported on the LCA of wastewater treatments using membranes. Overall, this study had proffered insights into the environmental impact of microalgal wastewater treatment and its stimulus for sustainable wastewater management. The findings of this study can be instrumental in making informed decision for optimizing microalgal wastewater treatment and reutilization assisted by membrane technology with an ultimate goal of enhancing sustainability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
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11. Process modelling and techno-economic analysis of anaerobic digestion of sewage sludge integrated with wet oxidation using a gravity pressure vessel and thermal hydrolysis.
- Author
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Das T, Al-Waili I, Balasubramanian V, Appleby G, Kaparaju P, Parthasarathy R, and Eshtiaghi N
- Abstract
Anaerobic digestion (AD) of sewage sludge is used to biodegrade sewage sludge into biomethane and digestate. With the addition of thermal processes such as thermal hydrolysis (TH) and wet oxidation (WO), AD biodegradability generally improves. Implementation of additional treatment is challenging due to the limitation in the mass and energy balances. Hence, tools such as process simulation can be utilized to predict the input and output around the process. In addition, an economic analysis needs to be conducted to check the economic feasibility. The techno-economic analysis (TEA), an integrated method to evaluate a process scheme through simulation and subsequent economic analysis, is effective in providing a systematic understanding of economic implications and the feasibility of a process by identifying the bottlenecks and uncertainties that have a significant impact on the technology. TEA of AD, especially incorporating the TH or WO using gravity pressure vessel (GPV) technology, is limited in the literature. A comprehensive TEA of the AD and the pre- and post-treatment schemes can be utilized to determine the most feasible pathway for sludge treatment for implementation in the wastewater industry. In this study, TEA for four different scenarios of AD was conducted using Aspen Plus and economic analysis tools: (1) without any pre- or post-treatment, (2) with TH pre-treatment, (3) with 100 % WO post-treatment, and (4) with 20 % partial wet oxidation (PWO) and acid hydrolysis pre- or post-treatment. A simulation model (GPVM) was developed using Aspen Plus to mimic the GPV reactor. The study outcomes showed that Scenario 3 with 100 % WO post-treatment was the most suitable for processing parameters and sludge treatment cost. The sensitivity analysis concluded that operating cost and plant capacity are the dominant factors that impact the plant feasibility significantly., Competing Interests: Declaration of competing interest Tanmoy Das, Ibrahim Al-Waili reports financial support was provided by PRJ00000574 Fast Track., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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12. An optimized approach towards bio-capture and carbon dioxide sequestration with microalgae Phormidium valderianum using response surface methodology.
- Author
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Suresh Nair M, Rajarathinam R, Velmurugan S, and Subhani S
- Subjects
- Carbon Dioxide metabolism, Carbon Sequestration, Biomass, Microalgae metabolism, Cyanobacteria metabolism
- Abstract
As carbon dioxide emissions rise, there's need for alternative strategies, including microorganisms, to capture and mitigate them. The present study investigated on the capability and tolerance of microalgal strain, Phormidium valderianum to capture gaseous CO
2 at varying levels (5-30 %). A biomass productivity of 0.0216 ± 0.027 gL-1 day-1 and rate of CO2 fixation of 0.035 gL-1 day-1 was obtained for 25 % CO2 concentration. From this study, it is evident that higher CO2 levels led to elevated carbohydrate concentration. In addition, protein concentration doubled with the introduction of 25 % CO2 . In optimization studies, pH 10, 25 % CO2 , and 200 mg/L of Ca(OH)2 concentration was found to be optimal for biomass growth. A higher rate of CO2 fixation of 0.315 gL-1 day-1 was achieved at these optimum conditions using response surface methodology. Furthermore, the study demonstrated that microalgae, Phormidium valderianum has the potential to serve as a promising alternative for capturing CO2 emissions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
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13. Biotreatment of Industrial Wastewater using Microalgae: A Tool for a Sustainable Bioeconomy.
- Author
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Elangovan B, Detchanamurthy S, Senthil Kumar P, Rajarathinam R, and Deepa VS
- Abstract
Fresh water is one of the essential sources of life, and its requirement has increased in the past years due to population growth and industrialization. Industries use huge quantities of fresh water for their processes, and generate high quantities of wastewater rich in organic matter, nitrates, and phosphates. These effluents have contaminated the freshwater sources and there is a need to recycle this wastewater in an ecologically harmless manner. Microalgae use the nutrients in the wastewater as a medium for growth and the biomass produced are rich in nutrition that can cater growing food and energy needs. The primary and secondary metabolites of microalgae are utilized as biofuel and as active ingredients in cosmetics, animal feed, therapeutics, and pharmaceutical products. In this review, we explore food processing industries like dairy, meat, aquaculture, breweries, and their wastewater for the microalgal growth. Current treatment methods are expensive and energy demanding, which indirectly leads to higher greenhouse gas emissions. Microalgae acts as a potential biotreatment tool and mitigates carbon dioxide due to their high photosynthetic efficiency. This review aims to address the need to recycle wastewater generated from such industries and potentiality to use microalgae for biotreatment. This will help to build a circular bioeconomy by using wastewater as a valuable resource to produce valuable products., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2023
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14. A study of biochar physiochemistry and particle size distribution influencing the properties of water-based slurry fuels.
- Author
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Zepeda LC, Griffin G, Shah K, Bhargava S, and Parthasarathy R
- Abstract
Biochar-based slurry is a fossil-free-liquid fuel derived from a renewable source, biomass. This study aims to examine the properties of this fuel as an alternative to coal-water slurries. The slurries were produced by suspending 40 wt% biochar in a solution made of water and a surfactant. Two biochar types from chemically treated and untreated rice straw (RS) were utilized to assess the impact of particle-particle interactions and biochar physicochemical composition on slurry properties, including stability, rheology, and heating value. Additionally, three particle size distributions (PSD), two unimodal and a bimodal, were used to analyze the effect of PSD on the abovementioned properties. All slurries had an average energy content of 7.32 ± 0.27 MJ/kg. The stability of the slurry was higher for fine particles from treated RS with unimodal PSD (D
v50 8.8 ± 0.68 μm). However, slurries containing fine and coarse particles with bimodal PSD (Dv50 15.8 ± 0.64 μm) had relatively lower apparent viscosities of 342.1 and 336.55 mPa.s at a shear rate of 100 s-1 for slurries made of biochar from treated and untreated RS, respectively. Slurries containing coarse particles from treated and untreated RS with unimodal PSD (Dv50 18.6 ± 0.32 μm) led to higher viscosities and particle settling rates. Biochar morphology and chemical surface constitution significantly influenced slurry stability, while PSD greatly impacted rheological results., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lolita Cueva Zepeda reports financial support was provided by the School of Engineering, RMIT University, Melbourne, Australia., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2023
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15. Functionalized nanofibers in gas sorption process: a critical review on the challenges and prospective research.
- Author
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Nithya R, Thirunavukkarasu A, Hemavathy RV, Sivashankar R, Kishore KA, and Sabarish R
- Subjects
- Humans, Prospective Studies, Environmental Monitoring, Particulate Matter analysis, Air Pollutants analysis, Nanofibers
- Abstract
Air pollution has become the most important environmental and human health threat as it is accounting for about 7 million deaths across the globe every year. Particulate matter (PM) derived from the combustion of fossil fuels, biomass, and other agricultural residues pollutes the atmospheric air which affects the quality of the environment and poses a great threat to human health. Ecological imbalance, climatic variation, and cardiovascular and respiratory problems among humans are significant extortions due to PM pollution. Scientific approaches were initiated to limit the levels of PM in the atmospheric air and the use of nanofiber mats has received wide attention as these possess versatile properties including nanoscale-sized pore structure, homogeneity in their size distribution with high specific surface area, and low basis weight. To exploit their filtration potential towards wide classes of pollutants and also to enhance the capturing efficacy, functionalized nanofibers are currently in practice with tailor-made modifications on the surface. The present review provides a comprehensive report on the different fabrication processes of functionalized nanofibers along with the controlling factors affecting the efficacy of the gas separation process. Also, it provides technical insights on the mass transfer aspects of PM filtration by elucidation their mechanism which can provide vital information on the rate-controlling diffusive flux(es). Conclusively, the practical challenges encountered in the large-scale air filtration systems such as filter cleaning, flow-rate regulation, pressure drop, and extent of reusability are discussed, and the review has identified potential gaps in the current research and can be considered for the prospective research in the area of PM separation process., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
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- 2023
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16. Sustainable organic waste management using vermicomposting: a critical review on the prevailing research gaps and opportunities.
- Author
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Thirunavukkarasu A, Sivashankar R, Nithya R, Sathya AB, Priyadharshini V, Kumar BP, Muthuveni M, and Krishnamoorthy S
- Subjects
- Animals, Humans, Evidence Gaps, Prospective Studies, Agriculture, Soil, Manure, Waste Management, Oligochaeta
- Abstract
Logistic growth of human population, exponential rate in agronomic industries and feeble waste management practices have resulted in the massive generation of organic wastes. Vermicomposting is one of the eco-biotechnological practices to efficiently transform them into stable and nutrient-rich organic manure with the synergetic actions of earthworms and soil microbiota. Vermicompost, a derivative product has the desirable physicochemical traits such as excellent porosity, buffering actions, aeration and water holding capacity. Also the presences of enzymic and microbial secretions contribute to growth and disease resistance of the crops. Owing to the benefits of soil nutrients restoration and effective organic waste management, vermicomposting has gained much attention among the scientific researchers and organic farmers. The present review is intended to provide comprehensive information on the site selection, screening of earthworms, different modes of operation and their desirable micro-environmental conditions. Also, the review has critically identified the prevailing research gaps viz. limited studies on the substrate formulation or optimization designs, poor control on the operational variables, lack of field-level investigations, technological feasibility of scale-up process, economic viability and cost-benefit analysis. Prospective researches can be made on these hotspots to identify the vermicomposting as a successful and profitable business model in the circular economy.
- Published
- 2023
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17. Incidence, Clinical Profile, and Management of Keratitis Caused by Uncommon Species of Pseudomonas at a Tertiary Eye Care Center.
- Author
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Thamizhselvi S, Pooja A, Prajna L, Rameshkumar G, Prajna NV, and Karpagam R
- Subjects
- Humans, Retrospective Studies, Ulcer drug therapy, Incidence, Anti-Bacterial Agents therapeutic use, Risk Factors, Pseudomonas aeruginosa, Keratitis diagnosis, Keratitis drug therapy, Keratitis epidemiology, Eye Infections, Bacterial diagnosis, Eye Infections, Bacterial drug therapy, Eye Infections, Bacterial epidemiology, Corneal Injuries drug therapy, Corneal Ulcer diagnosis, Corneal Ulcer drug therapy, Corneal Ulcer epidemiology
- Abstract
Purpose: The purpose of this study was to study the incidence, demographic features, clinical course, profiling, and management of uncommon species of Pseudomonas keratitis (other than Pseudomonas aeruginosa ) at a tertiary eye care center., Methods: Thirty cases of culture-proven uncommon species of Pseudomonas keratitis between January 2017 and December 2021 were retrospectively studied. The incidence, demographic and clinical profile, predisposing factors, microbial results, treatment, and visual outcomes were analyzed. We evaluated the risk factors for poor treatment outcomes., Results: Among bacterial keratitis cases, uncommon species of Pseudomonas keratitis occurred at a rate of 2.2%. The mean age at presentation was 51.37 years, and the most common predisposing factor was corneal trauma (36.7%). The mean best corrected visual acuity (BCVA) [in log of minimum angle of resolution (logMAR)] at presentation was 1.99, and the mean ulcer size was 5.75 mm. On culture, 56.7% of the cases were identified as Pseudomonas putida , 26.7% as Pseudomonas stutzeri , 10% as Pseudomonas mendocina, and 3.3% each of Pseudomonas oryzihabitans and Pseudomonas alcaligenes . We recorded good treatment responses in 66.7% of cases with the medical therapy of a combination of broad-spectrum antibiotics, whereas 33.3% of cases required surgical intervention. The risk factors for poor clinical outcome were older age, ocular trauma, previous ocular surgeries, poor BCVA at presentation, large ulcer size, delayed treatment, hypopyon, and early complications such as perforation, limbal involvement, and total ulcer., Conclusions: Uncommon species of pseudomonas keratitis was more closely related to predisposing factors such as corneal trauma and other factors such as previous ocular surgeries, older age, large ulcers, longer duration of treatment, early surgical intervention in complicated cases, and poor visual outcome., Competing Interests: Conflicts of interest statement: The authors have no funding or conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2023
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18. Transdermal drug delivery systems for the effective management of type 2 diabetes mellitus: A review.
- Author
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Thirunavukkarasu A, Nithya R, and Jeyanthi J
- Subjects
- Humans, Administration, Cutaneous, Insulin therapeutic use, Drug Delivery Systems methods, Diabetes Mellitus, Type 2 drug therapy
- Abstract
Type 2 Diabetes mellitus (T2DM) is characterized by either insufficient insulin production or the inability to take it up for the glycemic regulation in the human body. According to WHO reports, T2DM will be the seventh-largest syndrome resulting in mortality by 2030. To tackle this chronic metabolic disorder, the person with diabetes population depends on subcutaneous administration (Sub-Q) of insulin and certain oral hypoglycemic drugs. However, these current invasive practices suffered from painful injections, needle phobia, multiple doses, risk of infection and poor-patient compliance. Hence, the search for a non-invasive and patient-friendly insulin administration system was high in the past decades leading to the development of Transdermal Drug Delivery Systems (TDDS). These can offer rapid and sustained release of therapeutic compounds at controlled rates with no pain during the administration. In recent years, the usage of such TDDS has been increasing at an exponential rate in Type 2 diabetes management. In the present review, the scholarly works on the different modes of TDDS were comprehensively reported chronlogically to appreciate their developments. Conclusively, this review critically identified prevailing research gaps in the current TDDS research and presented potential research hotspots for the prospect development in T2DM management., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
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19. Metanil Yellow dye adsorption using green and chemical mediated synthesized manganese ferrite: An insight into equilibrium, kinetics and thermodynamics.
- Author
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Sivashankar R, Sivasubramanian V, Anand Kishore K, Sathya AB, Thirunavukkarasu A, Nithya R, and Deepanraj B
- Subjects
- Adsorption, Azo Compounds, Chlorides, Ferric Compounds, Glia Maturation Factor, Humans, Hydrogen-Ion Concentration, Kinetics, Male, Manganese Compounds, Prostate-Specific Antigen, Thermodynamics, Water Pollutants, Chemical analysis, Water Purification methods
- Abstract
Green Manganese Ferrite (GMF) and Chemical mediated Manganese Ferrite (CMF) were designed and prepared via in situ co-precipitation method and their adsorption potential was compared using the model dye, Metanil Yellow (MY). Previously, an extract of aquatic macrophyte and metal chloride were employed for the development of ecofriendly GMF. Alternatively, CMF has been synthesized through chemical co-precipitation from metal chloride precursors. Several characterization methods, including PSA, BET, TGA, DSC, FTIR, SEM, VSM, EDX, and XRD, were analyzed to reveal the structural and functional properties of the as-synthesized GMF and CMF. Their MY adsorption performances were tested as the function of the operational conditions such as initial solution pH, temperature, nanocomposite dosage, and dye concentration in a batch mode of operation. The pseudo-second order MY adsorption process fits best in Langmuir model which yielded the maximal monolayer adsorption capacity (q
max ) of 391.34 mg/g for GMF and 271.89 mg/g for CMF. This outperformance of GMF over CMF was observed due to the augmentation of specified surface functional moieties derived from the phyto-constituents of macrophages. Further, the thermodynamic studies confirmed the chemisorptive and exothermic nature of adsorption processes. Conclusively, with the ease of regeneration and reuse potential, GMF and CMF could be viable contenders for scale up and industrial applications., Competing Interests: Declaration of competing interest The authors declare that they have no known financial competing interest or personal relationship that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
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20. Maximization of growth and lipid production of a toxic isolate of Anabaena circinalis by optimization of various parameters with mathematical modeling and computational validation.
- Author
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Sarkar A, Rajarathinam R, Kumar PS, and Rangasamy G
- Subjects
- Carbon metabolism, Ecosystem, Lipids, Nitrogen metabolism, Anabaena metabolism, Cyanobacteria metabolism
- Abstract
Toxic cyanobacterial blooms are recurrent for few decades throughout the globe, due to climate change, atmospheric warming and various anthropogenic activities with severe impacts of potential toxins on various ecosystems finally affecting the entire environment. These cyanobacteria are merely unexplored regarding their biochemical components except toxins. Variable influences and interactions of different factors including nitrogen, carbon, and availability of light are well known to crucially regulate cyanobacterial growth and metabolism. Thus, current research work is motivated for the evaluation and optimization of the effects of the aforementioned vital factors for improvement of biomass and lipid production of a freshwater, toxic strain of Anabaena circinalis. The modelling and optimization of factors such as nitrogen, light intensity and bicarbonate concentration (source of carbon) to maximize growth and lipid production were based on 20 design point experiments by Response Surface Methodology (RSM) and optimized values were further improved and validated by Particle Swarm Optimization (PSO) algorithm. The maximum optima were obtained 1.829 g L
-1 and 39.64 % for biomass production and lipid content respectively from PSO optimization with two different sets of optimal values of factors. It shows 0.44 % and 2.77 % higher values of responses than that of RSM optimization. These asynchronous findings pioneered the enhanced lipid accumulation as well as the growth of a toxic cyanobacterium by optimizing interaction effects of culture conditions through various statistical and computational approaches., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
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21. Machine learning aided experimental approach for evaluating the growth kinetics of Candida antarctica for lipase production.
- Author
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Sarmah N, Mehtab V, Bugata LSP, Tardio J, Bhargava S, Parthasarathy R, and Chenna S
- Subjects
- Basidiomycota, Enzymes, Immobilized metabolism, Fungal Proteins, Kinetics, Machine Learning, Candida metabolism, Lipase metabolism
- Abstract
A hybrid machine learning (ML) aided experimental approach was proposed in this study to evaluate the growth kinetics of Candida antarctica for lipase production. Different ML models were trained and optimized to predict the growth curves at various substrate concentrations. Results on comparison demonstrate the superior performance of the Gradient boosting regression (GBR) model in growth curves prediction. GBR-based growth kinetics was found to be matching well with the results of the conventional experimental approach while significantly reducing the experimental effort, time, and resources by ∼ 50%. Further, the activity and enzyme kinetics of lipase produced in this study was investigated on hydrolysis of p-nitrophenyl butyrate resulting in a maximum lipase activity of 24.07 U at 44 h. The robustness and significance of developed kinetic models were ensured through detailed statistical analysis. The application of the proposed hybrid approach can be extended to any other microbial process., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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22. Investigation on the utilization of coal washery rejects by different microbial sources for biogenic methane production.
- Author
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Ponnudurai V, Rajarathinam R, Muthuvelu KS, Velmurugan S, Nalajala RK, and Arumugam L
- Subjects
- Biofuels, Sewage, Coal, Methane
- Abstract
High energy consumption and depletion of fossil fuels lead to the introduction of new technologies to produce alternative fuels with fewer emissions of greenhouse gases. The present investigation was focused to utilize the waste coal washery rejects as a substrate to produce biogenic methane under optimum conditions. Experiments were performed to explore the efficiency of non-coal samples (cow dung, distillery anaerobic digester sludge) and coal mines enriched samples in the degradation of coal washery rejects. Further cow dung, distillery anaerobic sludge, and coal washery rejects were taken at various concentrations to develop anaerobic slurry and analysed for its biogas production. The anaerobic slurry which contains 1:1:1 of cow dung, distillery anaerobic sludge, and coal washery rejects produced methane of around 55.7%. The coal enriched samples showed a maximum of 22.6% of methane. Subsequently, the best methane-producing anaerobic non-coal consortiums were compared with coal enriched microbial culture in converting coal washery rejects of 10 g/l to methane. Results revealed that cow dung inoculum and coal mine enriched inoculum source produced the nearly same amount of methane. This study suggested that the selected anaerobic slurries and coal enriched samples can utilize sub-bituminous coal washery rejects in methane production. Thus, these consortiums can be applied in converting a large amount of coal washery rejects into methane thus can lead to the reclamation of the site., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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23. Effect of Baffle Clearance on Scale Deposition in an Agitated Vessel.
- Author
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Sato E, Ochi Y, Horiguchi H, Takenaka K, Wu J, Parthasarathy R, Komoda Y, and Ohmura N
- Abstract
The material deposition in a mixing tank agitated by the MAXBLEND impeller in a turbulent state was quantified and compared between cases with and without baffle clearance. Magnesium hydroxide formed from the chemical reaction between calcium hydroxide and magnesium chloride was used as a model of scale formation. Flow velocity in the tank was investigated by employing computational fluid dynamics simulation and experimentally validated by an ultrasonic velocity profiler method. Results showed that the amount of scale decreased with the increase in the rotational speed of the impeller due to the erosion effect on the tank wall. In the case without baffle clearance, the smaller weight of the scale was deposited on the front of the baffle plate due to the flow impingement, which enhanced the removal of the scale deposition. However, the lower-velocity magnitude behind the baffles resulted in an enhancement in the formation of scale. Installation of baffle clearance caused a contraction flow in between the tank wall and baffles, and consequently, the higher flow velocity reduced the amount and thickness of the scale. Measurement of the torque showed that the baffle clearance did not affect the power consumption, so the installation of baffle clearance can be a promising approach to reduce scale deposition in terms of saving operational costs and increasing process efficiency and safety., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)
- Published
- 2021
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24. A comparative assessment of growth, pigment and enhanced lipid production by two toxic freshwater cyanobacteria Anabaena circinalis FSS 124 and Cylindrospermopsis raciborskii FSS 127 under various combinations of nitrogen and phosphorous inputs.
- Author
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Sarkar A, Rajarathinam R, and Venkateshan RB
- Subjects
- Fresh Water, Lipids, Nitrogen, Cyanobacteria, Cylindrospermopsis
- Abstract
Nitrogen and phosphorous are important nutritional regulators for the growth of cyanobacteria, thereby having a significant impact in bloom formation by toxic species. Usage of toxic cyanobacteria for increasing valuable metabolite production by nutrient manipulation is still unexplored. Hence, the current work is aimed to estimate and compare growth, pigment, and increased lipid production coupled with the identification of fatty acids between two toxic strains-Anabaena circinalis FSS 124 and Cylindrospermopsis raciborskii FSS 127 under various combinations of these two nutrients. Low level of nitrogen and phosphorous enhanced lipid content in both strains (˃ 20% and 30% respectively) and C. raciborskii, respectively. Lipid productivity in low phosphorous concentration (P0.5) was achieved significantly high in C. raciborskii. Similarly, a substantial amount of carotenoids was obtained at reduced nitrogen and phosphorous in C. raciborskii accompanied by lessened growth and Chl a concentration. Unlikely, enough biomass (˃ 2 g L
- 1 ) was produced at high nutrient levels in both species. Comparative statistical significance (p < 0.05) was found between two species regarding biomass production, chlorophyll concentration, lipid content, and productivity and between these factors in each species under both nutrient variations. FAME of Cylindrospermopsis is composed of saturated fatty acids (˃ 50%) and MUFA (˃ 25%) while Anabaena contains PUFA (˃ 21%) additionally. However, the study highlights C. raciborskii as potential lipid and carotenoid producer at nutrient stress and finds a novel way to utilize these cyanobacterial biomasses, which cause immense environmental hazards and life threats.- Published
- 2021
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25. Gene Therapy Options as New Treatment for Inherited Peripheral Neuropathy.
- Author
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Thenmozhi R, Lee JS, Park NY, Choi BO, and Hong YB
- Abstract
Inherited peripheral neuropathy (IPN) is caused by heterogeneous genetic mutations in more than 100 genes. So far, several treatment options for IPN have been developed and clinically evaluated using small molecules. However, gene therapy-based therapeutic strategies have not been aggressively investigated, likely due to the complexities of inheritance in IPN. Indeed, because the majority of the causative mutations of IPN lead to gainof- function rather than loss-of-function, developing a therapeutic strategy is more difficult, especially considering gene therapy for genetic diseases began with the simple idea of replacing a defective gene with a functional copy. Recent advances in gene manipulation technology have brought novel approaches to gene therapy and its clinical application for IPN treatment. For example, in addition to the classically used gene replacement for mutant genes in recessively inherited IPN, other techniques including gene addition to modify the disease phenotype, modulations of target gene expression, and techniques to edit mutant genes have been developed and evaluated as potent therapeutic strategies for dominantly inherited IPN. In this review, the current status of gene therapy for IPN and future perspectives will be discussed.
- Published
- 2020
- Full Text
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26. A novel method for improving laccase activity by immobilization onto copper ferrite nanoparticles for lignin degradation.
- Author
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Muthuvelu KS, Rajarathinam R, Selvaraj RN, and Rajendren VB
- Subjects
- Enzyme Stability, Glutaral chemistry, Hydrogen-Ion Concentration, Kinetics, Temperature, Copper chemistry, Enzymes, Immobilized chemistry, Ferric Compounds chemistry, Laccase chemistry, Lignin chemistry, Magnetite Nanoparticles chemistry
- Abstract
In this paper, a novel method for simultaneous enhancement of catalytic activity and reusability of laccase was carried out to overcome the limitations on industrial application of laccase. The immobilization of laccase onto copper ferrite magnetic nanoparticles (CuMNPs) and ferrite magnetic nanoparticles (MNPs) were optimized at 50 mM glutaraldehyde concentration and 1:5 enzyme:nanoparticles (NPs) ratio for 9 h of cross-linking time, yielding a maximum activity recovery of 94.68 ± 0.92% and 89.78 ± 1.24%, respectively. The laccase immobilized NPs were characterized using physico-chemical methods such as SEM-EDAX, FTIR, XRD, TGA and VSM and the laccase immobilized CuMNPs showed 18% higher activity as compared to free enzyme. The prepared CuMNPs and MNPs showed superior thermal stability (50-70 °C) with t
1/2 increased by 5.7 and 4.1 folds, respectively, as compared to free laccase. The laccase in immobilized forms exhibited higher kinetic potential and stable at wide temperature and pH range. In addition, laccase immobilized NPs retained more than 70% residual activity during reuse up to 6 cycles and storing for 20 days at 4 °C. The laccase immobilized CuMNPs showed higher delignification (43.28 ± 1.46%) on Ipomoea carnea than laccase immobilized MNPs., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
27. Screening of microalgae for treating Garcinia cambogia wash water with potential lipid production.
- Author
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Budhi Venkatesan R and Rajarathinam R
- Subjects
- Biofuels, Biomass, Chlorophyta, Citrates, Dietary Supplements, Fruit, Lipids, Plant Extracts, Garcinia cambogia, Microalgae, Waste Disposal, Fluid methods
- Abstract
The microalgae-based water treatment is gaining importance in recent years as it serves multiple purposes of which includes water treatment and biofuel production. Garcinia cambogia, a Malabar tamarind is a tropical fruit and the active ingredient hydroxycitric acid is popularly used as a weight-loss supplement. After extraction of the hydroxycitric acid, the wash water of G. cambogia is considered as an effluent. The potential microalgal species that can grow and treat G. cambogia wash water were isolated and identified as Dicloster acuatus BVR1 and Kalenjenia gelanitosa BVR2. Both the microalgal species adapted to G. cambogia wash water and entered exponential phase after sixth day with maximum specific growth rate of 0.310 day
-1 for D. acuatus and 0.296 day-1 for K. gelanitosa during tenth day. The biomass productivity of D. acuatus was 0.03 g L-1 day-1 which is 58% higher than K. gelanitosa with 0.019 g L-1 day-1 . The microalgal strains besides water treatment were subsequently subjected for lipid extraction and lipid productivity determination. The lipid productivity of D. acuatus was 2.68 mg L-1 day-1 which is lesser compared to 3.38 mg L-1 day-1 for K. gelatinosa. Both the microalgal isolates were promising for G. cambogia wash water treatment and lipid production. Hence, an environment friendly approach of water treatment with simultaneous lipid production for biofuel conversion is conducted.- Published
- 2019
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28. Process optimization using response surface methodology for the removal of thorium from aqueous solutions using rice-husk.
- Author
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Varala S, Ravisankar V, Al-Ali M, Pownceby MI, Parthasarathy R, and Bhargava SK
- Subjects
- Adsorption, Diffusion, Hydrogen-Ion Concentration, Kinetics, Metals, Oryza, Solutions, Thorium analysis, Water, Water Pollutants, Chemical analysis, Thorium chemistry, Water Pollutants, Chemical chemistry
- Abstract
The adsorptive capability of rice-husk for the sorption of thorium ions from aqueous solutions in batch mode was studied. The key process variables (initial metal ion concentration, initial solution pH and S/L (solid-to-liquid ratio) were optimized for achieving maximum bioremoval efficiency (B%) by employing the Box-Behnken design (33) in response surface methodology (RSM). A quadratic model developed by fitting the experimental data predicted 93% of the responses and estimated the local maximum of B% as >99% for an initial ThIV concentration of 150 g/L, S/L ratio of 5, and an initial pH of 4, and the reported biosorption capacity (qe) is 15.95 mg/g for the same conditions. Freundlich isotherm (R
2 = 0.9841) and pseudo-first-order (R2 = 0.9416) kinetic models had the best concurrence with the experimental data in the thorium concentration range used implying the sorption mechanism involves surface biosorption and intraparticle diffusion., (Copyright © 2019. Published by Elsevier Ltd.)- Published
- 2019
- Full Text
- View/download PDF
29. Rheological characterization of thermal hydrolysed waste activated sludge.
- Author
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Hii K, Farno E, Baroutian S, Parthasarathy R, and Eshtiaghi N
- Subjects
- Hydrolysis, Rheology, Viscosity, Sewage
- Abstract
Rheological properties are important in the design and operation of sludge-handling process. Despite this, the rheology of sludge in thermal hydrolysis processes (TH) is not well described. In-situ measurements were performed to characterize the flow behaviour of various concentrations (7-13 wt%) of waste activated sludge (WAS) at TH conditions. Equations were presented for predicting in-situ rheological parameters (high-shear viscosity, η
∞ ,i , consistency index, ki , and yield stress, σc,i ) under various treatment conditions, which are useful for design of process units. The equations enable convenient estimation of in-situ properties based on ambient rheological measurements. Results suggested that the proportion of sludge solubilization and its rate were unaffected by varying sludge concentration. Thermally treated sludge still exhibited gel-like, viscoelastic characteristics similar to untreated sludge; however, the storage (G') and loss (G") moduli decreased with higher treatment temperatures. Frequency and creep responses were described by a fractional derivatives Kelvin-Voigt (FKV) model, which showed increasing viscous characteristics of treated sludge. These equations can be utilised in CFD models. Results obtained from oscillatory measurements can also approximate steady-shear behaviour by comparing dynamic viscosity, η'(ω), and steady-shear viscosity, η(γ̇), whose values were very similar. This enables convenient estimation of steady-shear behaviour of sludge from oscillatory measurements, which is found to be a non-destructive technique for measuring flow behaviour of highly concentrated sludge. Yield stress can also be predicted from the product of modified Cox-Merz shift factors and storage modulus (G'). Practical engineering implications of the rheological observations were discussed., (Copyright © 2019 Elsevier Ltd. All rights reserved.)- Published
- 2019
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30. Synthesis of Silica-Coated Magnetic Hydroxyapatite Composites for Drug Delivery Applications.
- Author
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Thenmozhi R, Moorthy MS, Sivaguru J, Manivasagan P, Bharathiraja S, Oh YO, and Oh J
- Subjects
- Drug Delivery Systems, Durapatite, Magnetic Phenomena, Magnetics, Pharmaceutical Preparations, Silicon Dioxide
- Abstract
We have prepared a core-shell magnetic silica-coated hydroxyapatite, Fe₃O₄@SiO₂@HAp composite materials for pH-responsive drug delivery applications. Captopril (Cap) and ibuprofen (Ibu) were chosen as model hydrophilic and hydrophobic drugs, respectively. The drugs were encapsulated into the Fe₃O₄@SiO₂@HAp composite via electrostatic interactions with existing amine and carboxylic acid groups during calcium phosphate shell formation. The formation of calcium phosphate shell not only protects the encapsulated drugs from leaching but also controls the release rate of drugs from the composite system depending on various pH conditions. We have tested the release behavior of Cap and Ibu drugs under different pH conditions such as neutral pH (pH 7.4) and acidic pH (pH 5.0), respectively. The study result reveals that the synthesized Fe₃O₄@SiO₂@HAp composite is suitable for release of both water soluble and water insoluble drugs based on a pH-responsive controlled manner.
- Published
- 2019
- Full Text
- View/download PDF
31. Evaluation and characterization of novel sources of sustainable lignocellulosic residues for bioethanol production using ultrasound-assisted alkaline pre-treatment.
- Author
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Muthuvelu KS, Rajarathinam R, Kanagaraj LP, Ranganathan RV, Dhanasekaran K, and Manickam NK
- Subjects
- Biomass, Fermentation, Hydrolysis, Lignin, Biofuels, Ethanol
- Abstract
In recent years, research is focused on finding a sustainable and eco-friendly lignocellulosic biomass for the effective production of bioethanol to meet the world's energy demand. The present study investigates the bioethanol production potential of four different lignocellulosic biomass residues viz., Saccharum arundinaceum (hardy sugar cane), Arundo donax (giant reed), Typha angustifolia (narrow-leaved cattail), and Ipomoea carnea (pink morning glory). The maximum reducing sugar release showed 185.00 ± 1.57, 213.73 ± 3.47, 187.57 ± 2.14, 294.08 ± 3.98 mg/g and fermentation efficiency of 72.60 ± 8.17%, 82.59 ± 7.42%, 77.45 ± 7.35%, and 85.04 ± 8.37% which was analyzed by estimating the percentage of bioethanol yield were achieved for Saccharum arundinaceum, Arundo donax, Typha angustifolia, and Ipomoea carnea, respectively. The chemical composition of biomass was characterized using National Renewable Energy Limited (NREL) protocol. The effect of ultrasound (US)-assisted alkaline pre-treatment on the four biomasses was characterized by different techniques. The cavitation phenomena of US-assisted alkaline pre-treatment was evident from the decreased value of lignin percentage, increased surface porosity and area, changes in crystallinity index (CrI) values and in the functional groups of biomass. The results revealed that all the four lignocellulosic biomass residues could be utilized as an effective and sustainable source for the production of bioethanol using US-assisted sodium hydroxide as a pre-treatment tool., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
32. Process intensification of anaerobic digestion: Influence on mixing and process performance.
- Author
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McLeod JD, Othman MZ, and Parthasarathy R
- Subjects
- Biofuels analysis, Sewage, Waste Disposal, Fluid methods, Anaerobiosis
- Abstract
The adoption of process intensification to anaerobic digestion can present significant complications for digester mixing and process performance. This work investigated how increasing the solids concentration of the digester sludge influenced the process at various mixing energy inputs. Based on the results, adequate mixing is defined qualitatively as the input of sufficient energy to mobilize the reactor contents without producing significant regions of inhibitory shear force. However, the quantitative definition is dependent on the solids concentration of the sludge. But, the existing design criterion of specific mixing power input based on fluid volume (W/m
3 ) does not represent it well. Therefore, a new design criterion of specific mixing power input based on total solids in the sludge (W/kgTS) is proposed to achieve maximum biogas production using optimum power input. The relationship has its limitations, but it represents a significant step forward in the design and operation of improved digester mixing systems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
33. Suitability of Dicloster acuatus MH013435 and Kalenjinia gelatinosa MH012185 for growth in Garcinia cambogia washwater effluent with efficient nutrient removal.
- Author
-
Budhi Venkatesan R and Rajarathinam R
- Subjects
- Biodegradation, Environmental, Biomass, Garcinia cambogia, Nutrients, Wastewater, Chlorophyta, Microalgae
- Abstract
The present study investigates the suitability of growing Dicloster acuatus MH013435 and Kalenjinia gelatinosa MH012185 in Garcinia cambogia washwater for biomass production and nutrient removal. In recent years, the wastewater effluent treatment with microalgae is gaining importance since it serves multiple purposes including CO
2 sequestration, production of biofuel feedstock and value-added biochemicals in addition to wastewater treatment. Contaminated washwater is generated at a significant quantity during extraction of hydroxycitric acid from G. cambogia and it represents a serious environmental concern when discharged without proper processing. However, this G. cambogia washwater can be used as a low-cost source of nutrients for microalgal growth. The two microalgal species D. acuatus MH013435 and K. gelatinosa MH012185 demonstrated robust growth in washwater and achieved maximum biomass concentration of 0.68 and 0.63 g/L dry weight. The nitrate was removed to an extent of 98.5 and 99.6% whereas chloride removal was 72 and 80.5%, sulfate concentration got reduced by 98 and 98.7% and phosphate got reduced to 95 and 92% for D. acuatus MH013435 and K. gelatinosa MH012185, respectively. The results indicate the suitability of D. acuatus MH013435 and K. gelatinosa MH012185 in treating G. cambogia washwater with efficient nutrient removal.- Published
- 2019
- Full Text
- View/download PDF
34. Development of co-immobilized tri-enzyme biocatalytic system for one-pot pretreatment of four different perennial lignocellulosic biomass and evaluation of their bioethanol production potential.
- Author
-
Kirupa Sankar M, Ravikumar R, Naresh Kumar M, and Sivakumar U
- Subjects
- Biomass, Ethanol, Fermentation, Hydrolysis, Biofuels, Cellulase metabolism, Saccharum
- Abstract
Today, many researchers are focusing on research for alternative promising energy sources and sustainable technology for bioethanol production to meet the increasing global energy demand. Here, we develop a novel one-pot pretreatment technology by co-immobilizing laccase, cellulase and β-glucosidase to act as a tri-enzyme biocatalyst for evaluating the bioethanol production potential of four sustainable lignocellulosic biomasses viz., Typha angustifolia, Arundo donax, Saccharum arundinaceum, and Ipomoea carnea. The co-immobilized enzyme system was more stable at different temperatures and at longer storage, compared to free enzyme. During enzymatic saccharification, Saccharum arundinaceum showed higher total reducing sugar of 205 ± 3.73 mg/g when compared to other biomass. The highest percentage of bioethanol yield of 63.43 ± 9.35% was obtained with Ipomoea carnea. The effects of co-immobilized tri-enzyme biocatalyst on the biomasses were evaluated. The results revealed that the co-immobilized tri-enzyme biocatalyst could act as effective one-pot pretreatment for the production of bioethanol from lignocellulosic biomass., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
35. New insight into the effect of fungal mycelia present in the bio-pretreated paddy straw on their enzymatic saccharification and optimization of process parameters.
- Author
-
Naresh Kumar M, Ravikumar R, Kirupa Sankar M, and Thenmozhi S
- Subjects
- Biomass, Hydrolysis, Lignin, Oryza, Cellulase, Fungi
- Abstract
Assessment of Pleurotus florida efficiency on paddy straw pretreatment and optimization of saccharification parameters were studied. P. florida growth was monitored by the estimation of fungal cell wall component (glucosamine). The control bio-pretreatment sample showed high glucosamine content by 397 mg/g in 28 days of incubation. But, the Inhibitor Mediated Biological (IMB) Pretreatment showed 29% lower result due to the inhibition of cellulase enzyme limits mycelial penetration rate inside the paddy straw. Fungal components present inside the pretreated straw renders nonspecific interactions with the hydrolytic enzymes during saccharification process and reducing the hydrolysis efficiency. IMB pretreated paddy straw showed maximum saccharification efficiency up to 75.3% with optimized condition (Biomass loading- 10% (w/v), Enzyme loading- 20 FPU/g and saccharification time - 72 h) than control pretreatment sample. Thus, the study brings out new insight into the effect of fungal residues inside the bio-pretreated paddy straw during enzymatic saccharification to improve the efficiency., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
36. Quantitative investigation of hydraulic mixing energy input during batch mode anaerobic digestion and its impact on performance.
- Author
-
McLeod J, Othman MZ, and Parthasarathy R
- Subjects
- Anaerobiosis, Hydrolysis, Methane, Sewage, Waste Disposal, Fluid, Biofuels, Bioreactors
- Abstract
The relationship between mixing energy input and biogas production was investigated by anaerobically digesting sewage sludge in lab scale, hydraulically mixed, batch mode digesters at six different specific energy inputs. The goal was to identify how mixing energy influenced digestion performance at quantitative levels to help explain the varying results in other published works. The results showed that digester homogeneity was largely uninfluenced by energy input, whereas cumulative biogas production and solids destruction were. With similar solids distributions between conditions, the observed differences were attributed to shear forces disrupting substrate-microbe flocs rather than the formation of temperature and/or concentration gradients. Disruption of the substrate-microbe flocs produced less favourable conditions for hydrolytic bacteria, resulting in less production of biomass and more biogas. Overall, this hypothesis explains the current body of research including the inhibitory conditions reported at extreme mixing power inputs. However, further work is required to definitively prove it., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
37. In vitro and in silico antimicrobial activity of sterol and flavonoid isolated from Trianthema decandra L.
- Author
-
Geethalakshmi R and Sarada VLD
- Subjects
- Anti-Infective Agents isolation & purification, Flavonoids isolation & purification, Inhibitory Concentration 50, Magnetic Resonance Spectroscopy, Microbial Sensitivity Tests, Molecular Docking Simulation, Molecular Structure, Phytochemicals isolation & purification, Phytochemicals pharmacology, Plant Extracts pharmacology, Plant Leaves chemistry, Spectroscopy, Fourier Transform Infrared, Sterols isolation & purification, Tandem Mass Spectrometry, Vibrio cholerae drug effects, Aizoaceae chemistry, Anti-Infective Agents pharmacology, Flavonoids pharmacology, Sterols pharmacology
- Abstract
Phytochemical study on the leaves of Trianthema decandra leads to the isolation and characterization of two compounds from chloroform extract. The compounds were characterized using HPLC, UV, FT-IR, NMR, LCMS and CHNS. The structure of compounds were elucidated from spectral data and named according to rules laid down in IUPAC nomenclature. A novel sterol was named as 17-(5-ethyl-6-methylheptan-2-yl) -4, 4, 10, 13-tetramethyl-hexadecahydro-1H-cyclopenta (α) phenanthren-3-ol and the flavonoid was named as 2-(3, 4 dihydroxy - phenyl)-3, 5, 7 - trihydroxy-chromen-4 one. The antimicrobial activity of sterol and flavonoid isolated from T. decandra were examined by disc diffusion and broth dilution assays. The isolated compounds showed excellent activity against all the tested microorganisms. Sterol exhibits MIC value of 39.05 μg/ml against S. typhi whereas flavonoid shows 78.10 μg/ml against V. cholerae. The plausible mode of action of these compounds was studied using in silico molecular docking with Penicillin Binding Protein (PBP) as target., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
38. Antibacterial activity of flavonoid isolated from Trianthema decandra against Pseudomonas aeruginosa and molecular docking study of FabZ.
- Author
-
Geethalakshmi R, Sundaramurthi JC, and Sarada DVL
- Subjects
- Anti-Bacterial Agents isolation & purification, Flavonoids isolation & purification, Microbial Sensitivity Tests, Molecular Docking Simulation, Plant Extracts pharmacology, Protein Conformation, Aizoaceae chemistry, Anti-Bacterial Agents pharmacology, Bacterial Proteins antagonists & inhibitors, Flavonoids pharmacology, Pseudomonas aeruginosa drug effects
- Abstract
The natural product flavonoid demonstrates an extensive sort of pharmacological properties including antimicrobial activity. Although its Pseudomonas aeruginosa inhibition has been discovered, no target for action against flavonoid has been revealed to date. The anti - P. aeruginosa activity of the 2 - (3', 4' dihydroxy-phenyl) - 3, 5, 7-trihydroxy-chromen-4-one isolated from T. decandra was evaluated by disc diffusion and minimum inhibitory concentration methods. The molecular docking of the flavonoid isolated from T. decandra was carried out using CDOCKER (Discovery Studio 2.0). The flavonoid isolated from T. decandra was found to inhibit the growth of P. aeruginosa and the zone of inhibition was found to be 22 ± 0.04 mm at 20 μg/ml while chloramphenicol showed 23 ± 0.05 mm at 30 μg/ml. P. aeruginosa was found to be the most sensitive to both isolated flavonoid and standard control chloramphenicol with MIC values 39.05 μg/ml and 25 μg/ml respectively. Further, the FAS II β-hydroxyacyl-ACP (FabZ) of P. aeruginosa was found to be a potential target of the flavonoid as it docked in silico effectively. Our work has demonstrated the anti - P. aeruginosa activity of flavonoid isolated from T. decandra and also resulted in the elucidation of a plausible mechanism of action of the isolated flavonoid by inhibiting the FabZ using in silico analysis., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
39. Influences of novel microwave drying on dissolution of new formulated naproxen sodium.
- Author
-
Al-Ali M, Selvakannan PR, and Parthasarathy R
- Abstract
Drying of a pharmaceutical composition is an important step during its processing, which can affect its quality attributes including its texture, dispersion of the drug within the formulation, drug dissolution kinetics and eventually the drug's efficacy. This study presents the influence of varying drying techniques on the textural properties of the wet granulated formulation consisting of the drug naproxen sodium (NapSod) during the drying process. A new pharmaceutical formulation consisting of the NapSod drug was prepared by wet granulation and dried by novel microwave drying (MW), freeze drying (FD), vacuum drying (VD), and convective drying (CD) techniques before being processed in the form of tablets. The dissolution rate of NapSod from the tablet was measured in gastric (pH = 1.3) and intestinal fluid (pH = 6.8) mediums. The drug release was found to be influenced by the specific surface area, size distribution and the crystalline structure of dried particles, which were found to vary with the type of drying technique used as confirmed by the results of XRD, FTIR, SEM and particle size analyses. This study shows that using microwave technique to dry pharmaceutical granules containing a polar drug, such as NapSod, is an efficient and economical process, which can maintain the drug release at an appropriate rate to realize its desired pharmaceutical effect., Competing Interests: We authors declare that “There are no conflicts to declare.”, (This journal is © The Royal Society of Chemistry.)
- Published
- 2018
- Full Text
- View/download PDF
40. Control of the mixing time in vessels agitated by submerged recirculating jets.
- Author
-
Kennedy S, Bhattacharjee PK, Bhattacharya SN, Eshtiaghi N, and Parthasarathy R
- Abstract
Submerged recirculating jet mixing systems are an efficient and economical method of agitating large tanks with a high hydraulic residence time. Much work has been carried out in developing design correlations to aid the predictions of the mixing time in such systems, with the first such correlation being developed nearly 70 years ago. In most of these correlations, the mixing time depends directly on the volume of the vessel and inversely on the injection velocity of the submerged jet. This work demonstrates, for the first time, that the distance between the injection and suction nozzles also significantly affects the mixing time and can be used to control this time scale. The study introduces a non-dimensional quantity that can be used as an adjustable parameter in systems where such control is desired., Competing Interests: We declare we have no conflicts of interest.
- Published
- 2018
- Full Text
- View/download PDF
41. Development of natural cellulase inhibitor mediated intensified biological pretreatment technology using Pleurotus florida for maximum recovery of cellulose from paddy straw under solid state condition.
- Author
-
Naresh Kumar M, Ravikumar R, Thenmozhi S, and Kirupa Sankar M
- Subjects
- Laccase, Lignin, Cellulase, Cellulose, Pleurotus
- Abstract
Inhibitor mediated intensified bio-pretreatment (IMBP) technology using natural cellulase inhibitor (NCI) for maximum cellulose recovery from paddy straw was studied. Pretreatment was carried out under solid state condition. Supplementation of 8% NCI in pretreatment medium improves cellulose recovery and delignification by 1.2 and 1.5-fold respectively, compared to conventional bio-pretreatment due to inhibition of 61% of cellulase activity in IMBP. Further increase in NCI concentration showed negative effect on Pleurotus florida growth and suppress the laccase productivity by 1.1-fold. Laccase activity in IMBP was found to be 2.0U/mL on 19
th day, which is higher than (1.5U/mL) conventional bio-pretreatment. Physico-chemical modifications in paddy straw before and after pretreatment were analysed by SEM, ATR-FTIR, XRD and TGA. According to these findings, the IMBP technology can be a viable eco-friendly technology for sustainable production of bioethanol with maximum cellulose recovery., (Copyright © 2017 Elsevier Ltd. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF
42. Net positive energy wastewater treatment plant via thermal pre-treatment of sludge: A theoretical case study.
- Author
-
Farno E, Baudez JC, Parthasarathy R, and Eshtiaghi N
- Subjects
- Anaerobiosis, Biofuels, Humans, Models, Theoretical, Waste Management methods, Sewage chemistry, Temperature, Waste Disposal, Fluid methods, Wastewater chemistry
- Abstract
In a wastewater treatment process, energy is mainly used in sludge handling and heating, while energy is recovered by biogas production in anaerobic digestion process. Thermal pre-treatment of sludge can change the energy balance in a wastewater treatment process since it reduces the viscosity and yield stress of sludge and increases the biogas production. In this study, a calculation based on a hypothetical wastewater treatment plant is provided to show the possibility of creating a net positive energy wastewater treatment plant as a result of implementing thermal pre-treatment process before the anaerobic digester. The calculations showed a great energy saving in pumping and mixing of the sludge by thermal pre-treatment of sludge before anaerobic digestion process.
- Published
- 2017
- Full Text
- View/download PDF
43. Investigation of mass transfer intensification under power ultrasound irradiation using 3D computational simulation: A comparative analysis.
- Author
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Sajjadi B, Asgharzadehahmadi S, Asaithambi P, Raman AA, and Parthasarathy R
- Abstract
This paper aims at investigating the influence of acoustic streaming induced by low-frequency (24kHz) ultrasound irradiation on mass transfer in a two-phase system. The main objective is to discuss the possible mass transfer improvements under ultrasound irradiation. Three analyses were conducted: i) experimental analysis of mass transfer under ultrasound irradiation; ii) comparative analysis between the results of the ultrasound assisted mass transfer with that obtained from mechanically stirring; and iii) computational analysis of the systems using 3D CFD simulation. In the experimental part, the interactive effects of liquid rheological properties, ultrasound power and superficial gas velocity on mass transfer were investigated in two different sonicators. The results were then compared with that of mechanical stirring. In the computational part, the results were illustrated as a function of acoustic streaming behaviour, fluid flow pattern, gas/liquid volume fraction and turbulence in the two-phase system and finally the mass transfer coefficient was specified. It was found that additional turbulence created by ultrasound played the most important role on intensifying the mass transfer phenomena compared to that in stirred vessel. Furthermore, long residence time which depends on geometrical parameters is another key for mass transfer. The results obtained in the present study would help researchers understand the role of ultrasound as an energy source and acoustic streaming as one of the most important of ultrasound waves on intensifying gas-liquid mass transfer in a two-phase system and can be a breakthrough in the design procedure as no similar studies were found in the existing literature., (Copyright © 2016. Published by Elsevier B.V.)
- Published
- 2017
- Full Text
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44. Predicting the apparent viscosity and yield stress of mixtures of primary, secondary and anaerobically digested sewage sludge: Simulating anaerobic digesters.
- Author
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Markis F, Baudez JC, Parthasarathy R, Slatter P, and Eshtiaghi N
- Subjects
- Hydrodynamics, Models, Theoretical, Rheology, Sewage, Viscosity
- Abstract
Predicting the flow behaviour, most notably, the apparent viscosity and yield stress of sludge mixtures inside the anaerobic digester is essential because it helps optimize the mixing system in digesters. This paper investigates the rheology of sludge mixtures as a function of digested sludge volume fraction. Sludge mixtures exhibited non-Newtonian, shear thinning, yield stress behaviour. The apparent viscosity and yield stress of sludge mixtures prepared at the same total solids concentration was influenced by the interactions within the digested sludge and increased with the volume fraction of digested sludge - highlighted using shear compliance and shear modulus of sludge mixtures. However, when a thickened primary - secondary sludge mixture was mixed with dilute digested sludge, the apparent viscosity and yield stress decreased with increasing the volume fraction of digested sludge. This was caused by the dilution effect leading to a reduction in the hydrodynamic and non-hydrodynamic interactions when dilute digested sludge was added. Correlations were developed to predict the apparent viscosity and yield stress of the mixtures as a function of the digested sludge volume fraction and total solids concentration of the mixtures. The parameters of correlations can be estimated using pH of sludge. The shear and complex modulus were also modelled and they followed an exponential relationship with increasing digested sludge volume fraction., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
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45. Mixing characteristics of sludge simulant in a model anaerobic digester.
- Author
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Low SC, Eshtiaghi N, Slatter P, Baudez JC, and Parthasarathy R
- Subjects
- Models, Chemical, Sewage chemistry
- Abstract
This study aims to investigate the mixing characteristics of a transparent sludge simulant in a mechanically agitated model digester using flow visualisation technique. Video images of the flow patterns were obtained by recording the progress of an acid-base reaction and analysed to determine the active and inactive volumes as a function of time. The doughnut-shaped inactive region formed above and below the impeller in low concentration simulant decreases in size with time and disappears finally. The 'cavern' shaped active mixing region formed around the impeller in simulant solutions with higher concentrations increases with increasing agitation time and reaches a steady state equilibrium size, which is a function of specific power input. These results indicate that the active volume is jointly determined by simulant rheology and specific power input. A mathematical correlation is proposed to estimate the active volume as a function of simulant concentration in terms of yield Reynolds number.
- Published
- 2016
- Full Text
- View/download PDF
46. Association between in vitro susceptibility to natamycin and voriconazole and clinical outcomes in fungal keratitis.
- Author
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Sun CQ, Lalitha P, Prajna NV, Karpagam R, Geetha M, O'Brien KS, Oldenburg CE, Ray KJ, McLeod SD, Acharya NR, and Lietman TM
- Subjects
- Administration, Topical, Antifungal Agents pharmacology, Cicatrix pathology, Corneal Perforation diagnosis, Corneal Ulcer microbiology, Double-Blind Method, Epithelium, Corneal physiology, Eye Infections, Fungal microbiology, Fungi isolation & purification, Humans, Keratoplasty, Penetrating, Microbial Sensitivity Tests, Natamycin pharmacology, Ophthalmic Solutions, Re-Epithelialization, Treatment Outcome, Visual Acuity physiology, Voriconazole pharmacology, Antifungal Agents therapeutic use, Corneal Ulcer drug therapy, Eye Infections, Fungal drug therapy, Fungi drug effects, Natamycin therapeutic use, Voriconazole therapeutic use
- Abstract
Purpose: To assess the association between minimum inhibitory concentration (MIC) and clinical outcomes in a fungal keratitis clinical trial., Design: Experimental study using data from a randomized comparative trial., Participants: Of the 323 patients enrolled in the trial, we were able to obtain MIC values from 221 patients with monocular fungal keratitis., Methods: The Mycotic Ulcer Treatment Trial I was a randomized, double-masked clinical trial comparing clinical outcomes of monotherapy with topical natamycin versus voriconazole for the treatment of fungal keratitis. Speciation and determination of MIC to natamycin and voriconazole were performed according to Clinical and Laboratory Standards Institute guidelines. The relationship between MIC and clinical outcome was assessed., Main Outcome Measures: The primary outcome was 3-month best spectacle-corrected visual acuity. Secondary outcomes included 3-month infiltrate or scar size; corneal perforation and/or therapeutic penetrating keratoplasty; and time to re-epithelialization., Results: A 2-fold increase in MIC was associated with a larger 3-month infiltrate or scar size (0.21 mm; 95% confidence interval [CI], 0.10-0.31; P < 0.001) and increased odds of perforation (odds ratio, 1.32; 95% CI, 1.04-1.69; P = 0.02). No correlation was found between MIC and 3-month visual acuity. For natamycin-treated cases, an association was found between higher natamycin MIC with larger 3-month infiltrate or scar size (0.29 mm; 95% CI, 0.15-0.43; P < 0.001) and increased perforations (odds ratio, 2.41; 95% CI, 1.46-3.97; P < 0.001). Among voriconazole-treated cases, the voriconazole MIC did not correlate with any of the measured outcomes in the study., Conclusions: Decreased susceptibility to natamycin was associated with increased infiltrate or scar size and increased odds of perforation. There was no association between susceptibility to voriconazole and outcome., (Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
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47. Rheological characterisation of thermally-treated anaerobic digested sludge: impact of temperature and thermal history.
- Author
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Farno E, Baudez JC, Parthasarathy R, and Eshtiaghi N
- Subjects
- Anaerobiosis, Time Factors, Viscosity, Waste Disposal, Fluid methods, Hot Temperature, Rheology, Sewage chemistry
- Abstract
This study investigated the partially irreversible effect of thermal treatment on the rheology of digested sludge when it was subjected to temperature change between 20 °C and 80 °C and then cooled down to 20 °C. The yield stress, infinite viscosity and liquor viscosity of sludge were measured at 20 °C for different thermal histories and were compared to the evolution of the solubilised chemical oxygen demand (COD) of sludge liquor. The results showed that thermal history irreversibly affects sludge rheology as the yield stress of sludge which was heated to 80 °C then cooled down to 20 °C was 68% lower than the initial yield stress at 20 °C. This decrease was due to the irreversible solubilisation of solid matter during heating as underlined by soluble COD data which did not reach its original level after thermal treatment. Measured soluble COD of sludge which was heated and cooled down was much higher than the soluble COD of initial sludge. We found a proportionality of the increase of soluble COD with the decrease of the yield stress as well as increase of infinite viscosity., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
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48. In vitro susceptibility of filamentous fungal isolates from a corneal ulcer clinical trial.
- Author
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Lalitha P, Sun CQ, Prajna NV, Karpagam R, Geetha M, O'Brien KS, Cevallos V, McLeod SD, Acharya NR, and Lietman TM
- Subjects
- Adult, Corneal Ulcer drug therapy, Double-Blind Method, Eye Infections, Fungal drug therapy, Female, Fungi isolation & purification, Humans, Inhibitory Concentration 50, Male, Microbial Sensitivity Tests, Middle Aged, Mycoses drug therapy, Voriconazole, Antifungal Agents pharmacology, Corneal Ulcer microbiology, Eye Infections, Fungal microbiology, Fungi drug effects, Mycoses microbiology, Natamycin pharmacology, Pyrimidines pharmacology, Triazoles pharmacology
- Abstract
Purpose: To describe the minimum inhibitory concentration (MIC) of fungal isolates to natamycin and voriconazole, and to compare these MICs to previous ocular susceptibility studies., Design: Experimental laboratory study using isolates from a randomized clinical trial., Methods: The Mycotic Ulcer Treatment Trial I was a randomized, double-masked, multicenter trial comparing topical natamycin and voriconazole for fungal keratitis treatment. Susceptibility testing to natamycin and voriconazole were performed according to Clinical and Laboratory Standards Institute methods. The relationship between organism and MIC was assessed. A literature review was performed to compare results to previous ocular susceptibility studies., Results: Of the 323 patients enrolled in the trial, MICs were available for 221 (68%). Fusarium (n = 126) and Aspergillus species (n = 52) were the most commonly isolated organisms. MICs to natamycin and voriconazole were significantly different across all genera (P < .001). The MIC median (MIC50) and 90th percentile (MIC90) for natamycin were equal to or higher than voriconazole for all organisms except Curvularia species. Compared to other organisms, Fusarium species isolates had the highest MICs to voriconazole and Aspergillus flavus isolates had the highest MICs to natamycin. Our results were similar to previous reports except that the voriconazole MIC90 against Aspergillus species was 2-fold higher and the natamycin MIC90 against Aspergillus fumigatus was 4-fold higher in our study., Conclusion: In this large susceptibility study, Fusarium isolates were least susceptible to voriconazole and A flavus isolates were least susceptible to natamycin when compared to other filamentous fungi. In the future, susceptibility testing may help guide therapy if performed in a timely manner., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
49. Dimerization of a flocculent protein from Moringa oleifera: experimental evidence and in silico interpretation.
- Author
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Pavankumar AR, Kayathri R, Murugan NA, Zhang Q, Srivastava V, Okoli C, Bulone V, Rajarao GK, and Ågren H
- Subjects
- Computational Biology, Computer Simulation, Molecular Docking Simulation, Plant Proteins genetics, Protein Binding, Protein Interaction Domains and Motifs, Protein Multimerization, Recombinant Proteins chemistry, Recombinant Proteins genetics, Sequence Homology, Amino Acid, Thermodynamics, Moringa oleifera metabolism, Plant Proteins chemistry, Seeds metabolism
- Abstract
Many proteins exist in dimeric and other oligomeric forms to gain stability and functional advantages. In this study, the dimerization property of a coagulant protein (MO2.1) from Moringa oleifera seeds was addressed through laboratory experiments, protein-protein docking studies and binding free energy calculations. The structure of MO2.1 was predicted by homology modelling, while binding free energy and residues-distance profile analyses provided insight into the energetics and structural factors for dimer formation. Since the coagulation activities of the monomeric and dimeric forms of MO2.1 were comparable, it was concluded that oligomerization does not affect the biological activity of the protein.
- Published
- 2014
- Full Text
- View/download PDF
50. Fluoroquinolone treatment and susceptibility of isolates from bacterial keratitis.
- Author
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Ray KJ, Prajna L, Srinivasan M, Geetha M, Karpagam R, Glidden D, Oldenburg CE, Sun CQ, McLeod SD, Acharya NR, and Lietman TM
- Subjects
- Adult, Corneal Ulcer drug therapy, Double-Blind Method, Eye Infections, Bacterial drug therapy, Female, Fluoroquinolones, Glucocorticoids therapeutic use, Humans, Male, Microbial Sensitivity Tests, Middle Aged, Moxifloxacin, Nocardia drug effects, Nocardia Infections drug therapy, Nocardia Infections microbiology, Pneumococcal Infections drug therapy, Pneumococcal Infections microbiology, Prednisolone analogs & derivatives, Prednisolone therapeutic use, Pseudomonas Infections drug therapy, Pseudomonas Infections microbiology, Pseudomonas aeruginosa drug effects, Streptococcus pneumoniae drug effects, Anti-Bacterial Agents therapeutic use, Aza Compounds therapeutic use, Bacteria drug effects, Corneal Ulcer microbiology, Drug Resistance, Bacterial, Eye Infections, Bacterial microbiology, Quinolines therapeutic use
- Abstract
Objective: To analyze the relationship between fluoroquinolone use at presentation and minimum inhibitory concentration in bacterial keratitis., Methods: The Steroids for Corneal Ulcers Trial was a randomized, double-masked, placebo-controlled trial assessing the effect of adjunctive topical corticosteroid treatment on outcomes in bacterial keratitis. After presentation, all patients were treated with moxifloxacin hydrochloride, 0.5%. We compare antibiotic use at presentation with minimum inhibitory concentration against moxifloxacin for all isolates. Separate analyses accounted for organism species and fluoroquinolone generation., Results: Topical fluoroquinolone use at presentation was reported in 92 of 480 cases (19.2%). Causative organisms in the 480 cases included Streptococcus pneumoniae (247 cases [51.5%]), Pseudomonas aeruginosa (109 cases [22.7%]), and Nocardia species (55 cases [11.5%]). Isolates from patients who reported fluoroquinolone use at presentation had a 2.01-fold-higher minimum inhibitory concentration (95% CI, 1.39-fold to 2.91-fold; P < .001). Fourth-generation fluoroquinolones were associated with a 3.48-fold-higher minimum inhibitory concentration than those isolates that were not exposed to pretreatment at enrollment (95% CI, 1.99-fold to 6.06-fold; P < .001)., Conclusion: This study provides evidence that prior use of fluoroquinolones is associated with antibiotic resistance., Trial Registration: clinicaltrials.gov Identifier: NCT00324168.
- Published
- 2013
- Full Text
- View/download PDF
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