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Rao GN, Sekar G. Stable and Reusable Pd-nanoparticles Catalyzed Synthesis of Symmetrical and Unsymmetrical 1,2-Dicarbonyl compounds. NEW J CHEM 2023. [DOI: 10.1039/d2nj05538d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Highly stable and reusable Pd-nanoparticles (Pd-BNP) catalyzed oxidation of 1,2-diarylalkynes to 1,2-dicarbonyl compounds using DMSO as an oxidant has been developed. The Pd-BNP catalytic system also successfully oxidized the alkenes...
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Surendiran J, Theetchenya S, Benson Mansingh PM, Sekar G, Dhipa M, Yuvaraj N, Arulkarthick VJ, Suresh C, Sriram A, Srihari K, Alene A. Segmentation of Optic Disc and Cup Using Modified Recurrent Neural Network. Biomed Res Int 2022; 2022:6799184. [PMID: 35547359 PMCID: PMC9085314 DOI: 10.1155/2022/6799184] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 03/08/2022] [Accepted: 03/21/2022] [Indexed: 11/17/2022]
Abstract
Glaucoma is one of the leading factors of vision loss, where the people tends to lose their vision quickly. The examination of cup-to-disc ratio is considered essential in diagnosing glaucoma. It is hence regarded that the segmentation of optic disc and cup is useful in finding the ratio. In this paper, we develop an extraction and segmentation of optic disc and cup from an input eye image using modified recurrent neural networks (mRNN). The mRNN use the combination of recurrent neural network (RNN) with fully convolutional network (FCN) that exploits the intra- and interslice contexts. The FCN extracts the contents from an input image by constructing a feature map for the intra- and interslice contexts. This is carried out to extract the relevant information, where RNN concentrates more on interslice context. The simulation is conducted to test the efficacy of the model that integrates the contextual information for optimal segmentation of optical cup and disc. The results of simulation show that the proposed method mRNN is efficient in improving the rate of segmentation than the other deep learning models like Drive, STARE, MESSIDOR, ORIGA, and DIARETDB.
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Affiliation(s)
- J. Surendiran
- Department of Electronics and Communication Engineering, HKBK College of Engineering, India
| | - S. Theetchenya
- Department of Computer Science and Engineering, Sona College of Technology, India
| | - P. M. Benson Mansingh
- Department of Electronics and Communication Engineering, Sri Ramakrishna Institute of Technology, India
| | - G. Sekar
- Department of Electronics and Communication Engineering, Sri Ramakrishna Institute of Technology, India
| | - M. Dhipa
- Department of Electronics and Communication Engineering, Erode Sengunthar Engineering College, India
| | - N. Yuvaraj
- Research and Development, ICT Academy, IIT Madras Research Park, India
| | - V. J. Arulkarthick
- Department of Electronics and Communication Engineering, Karpagam Institute Technology, Coimbatore 641105, India
| | - C. Suresh
- Department of Computer Science Engineering, Sri Ranganathar Institute of Engineering and Technology, Coimbatore, India
| | - Arram Sriram
- Department of Information Technology, AnuragUniversity, Hyderabad, India
| | - K. Srihari
- Department of Computer Science and Engineering, SNS College of Technology, India
| | - Assefa Alene
- Department of Chemical Engineering, College of Biological and Chemical Engineering, Addis Ababa Science and Technology University, Ethiopia
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Kathamuthu GR, Moideen K, Baskaran D, Sekar G, Rathinam S, Bharathi VJ, Ganeshan GR, Babu S. Tuberculous lymphadenitis is associated with altered levels of circulating angiogenic factors. Int J Tuberc Lung Dis 2019; 22:557-566. [PMID: 29663962 DOI: 10.5588/ijtld.17.0609] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Angiogenic factors are important in granuloma formation and serve as biomarkers in pulmonary tuberculosis (PTB). The relationship between these markers and tuberculous lymphadenitis (TBL) is not known. OBJECTIVE AND DESIGN To examine the association of vascular endothelial growth factor (VEGF) and angiopoietin (Ang) family molecules in TBL, we measured systemic levels of VEGF-A, C, D, R1 (VEGF-receptor 1), R2, R3, Ang-1, Ang-2 and TIE2 (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) levels in TBL, latent tuberculous infection (LTBI) and lymph node culture supernatants (VEGF-A, C and Ang-2) of the same TBL patients. RESULTS Circulating levels of VEGF-A and VEGF-C were significantly diminished, whereas VEGF-R2, R3, Ang-2 and TIE2 levels were significantly increased, in TBL. Likewise, VEGF-A, C and Ang-2 levels were significantly increased in lymph node supernatants compared with plasma in individuals with TBL. Receiver operating characteristic curve analysis showed that VEGF-C and VEGF-R2 markers clearly distinguished TBL from LTBI. Following treatment, VEGF-C and Ang-1 levels were significantly altered. No association was observed between angiogenic factors and culture grade or lymph node size, except for VEGF-A. VEGF-A was also significantly decreased in multiple lymph nodes compared with single lymph nodes. CONCLUSIONS Our data suggest that altered levels of circulating angiogenic factors in TBL might reflect underlying vasculo-endothelial dysfunction. Reversal of angiogenic markers after anti-tuberculosis treatment suggests that these angiogenic markers may serve as biomarkers of disease severity or response to treatment in TBL.
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Affiliation(s)
- G R Kathamuthu
- International Centre for Excellence in Research, National Institutes of Health, Chennai, India; National Institute for Research in Tuberculosis, Chennai, India
| | - K Moideen
- International Centre for Excellence in Research, National Institutes of Health, Chennai, India
| | - D Baskaran
- National Institute for Research in Tuberculosis, Chennai, India
| | - G Sekar
- National Institute for Research in Tuberculosis, Chennai, India
| | - S Rathinam
- Government Stanley Medical Hospital, Chennai, India
| | - V J Bharathi
- Government Kilpauk Medical Hospital, Chennai, India
| | | | - S Babu
- International Centre for Excellence in Research, National Institutes of Health, Chennai, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Kumar RS, Kumar AMV, Claassens M, Banurekha VV, Sekar G, Venkatesan P, Swaminathan S. Are we justified in treating for multidrug-resistant tuberculosis based on positive follow-up smear results? Int J Tuberc Lung Dis 2014; 18:449-53. [PMID: 24670701 DOI: 10.5588/ijtld.13.0429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING National Institute for Research in Tuberculosis, India. OBJECTIVE To assess, among new culture-confirmed smear-positive pulmonary tuberculosis (TB) patients, the proportion of follow-up smear-positives that were culture-negative (S+C-) by month of follow-up examination, human immunodeficiency virus (HIV) status, pre-treatment drug susceptibility status and smear grading. DESIGN We extracted follow-up smear (fluorescence microscopy) and culture (Löwenstein-Jensen) results of patients enrolled in clinical trials from January 2000 to August 2012 and treated with the WHO Category I regimen (2EHRZ3/4HR3). RESULTS Of 520 patients, including 176 who were HIV-infected, respectively 199, 81, 47 and 43 were smear-positive at months 2, 4, 5 and 6; of these, respectively 138 (69%), 62 (75%), 32 (68%) and 27 (63%) were culture-negative. The S+C- phenomenon was more pronounced among '1+ positive' patients than in 2+ or 3+ positive patients and in 'pan-susceptible' patients than in those with any resistance, and did not vary by HIV status. CONCLUSION Nearly two thirds of patients with follow-up smears positive at months 5 and 6 were culture-negative. Starting multidrug-resistant TB (MDR-TB) treatment empirically based on smear results, even in resource-limited settings, is incorrect and can have hazardous consequences. There is an urgent need to revisit the WHO recommendation concerning empirical MDR-TB treatment.
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Affiliation(s)
- R S Kumar
- National Institute for Research in Tuberculosis, Chennai, India
| | - A M V Kumar
- International Union Against Tuberculosis and Lung Disease, South-East Asia Regional Office, New Delhi, India
| | - M Claassens
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, Cape Town, South Africa
| | - V V Banurekha
- National Institute for Research in Tuberculosis, Chennai, India
| | - G Sekar
- National Institute for Research in Tuberculosis, Chennai, India
| | - P Venkatesan
- National Institute for Research in Tuberculosis, Chennai, India
| | - S Swaminathan
- National Institute for Research in Tuberculosis, Chennai, India
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Ganapathi Subramanian AM, Ayyappan G, Sekar G. M/M/1 Retrial queueing system with negative arrival under non-preemptive priority service. Mal J Fund Appl Sci 2014. [DOI: 10.11113/mjfas.v5n2.295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Consider a single server retrial queueing system with negative arrival under non-pre-emptive priority service in which three types of customers arrive in a poisson process with arrival rate λ1 for low priority customers and λ2 for high priority customers and λ3 for negative arrival. Low and high priority customers are identified as primary calls. The service times follow an exponential distribution with parameters μ1 and μ2 for low and high priority customers. The retrial and negative arrivals are introduced for low priority customers only. Gelenbe (1991) has introduced a new class of queueing processes in which customers are either positive or negative. Positive means a regular customer who is treated in the usual way by a server. Negative customers have the effect of deleting some customer in the queue. In the simplest version, a negative arrival removes an ordinary positive customer or a random batch of positive customers according to some strategy. It is noted that the existence of a flow of negative arrivals provides a control mechanismto control excessive congestion at the retrial group and also assume that the negative customers only act when the server is busy. Let K be the maximumnumber of waiting spaces for high priority customers in front of the service station. The high priorities customers will be governed by the Non-preemptive priority service. The access from the orbit to the service facility is governed by the classical retrial policy. This model is solved by using Matrix geometric Technique. Numerical study have been done for Analysis of Mean number of low priority customers in the orbit (MNCO), Mean number of high priority customers in the queue(MPQL),Truncation level (OCUT),Probability of server free and Probabilities of server busy with low and high priority customers for various values of λ1 , λ2 , λ3 , μ1 , μ2 ,σ and k in elaborate manner and also various particular cases of this model have been discussed.
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Karthikeyan I, Alamsetti SK, Sekar G. Isolation and Characterization of a Trinuclear Cobalt Complex Containing Trigonal-Prismatic Cobalt in Secondary Alcohol Aerobic Oxidation. Organometallics 2014. [DOI: 10.1021/om500003d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- I. Karthikeyan
- Department
of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| | - S. K. Alamsetti
- Department
of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
| | - G. Sekar
- Department
of Chemistry, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
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Prasad DJC, Sekar G. Cu-catalyzed in situ generation of thiol using xanthate as a thiol surrogate for the one-pot synthesis of benzothiazoles and benzothiophenes. Org Biomol Chem 2013; 11:1659-65. [DOI: 10.1039/c3ob26915a] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Naidu AB, Sekar G. An efficient intermolecular BINAM–copper(I) catalyzed Ullmann-type coupling of aryl iodides/bromides with aliphatic alcohols. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.03.015] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Mannam S, Sekar G. CuCl catalyzed selective oxidation of primary alcohols to carboxylic acids with tert-butyl hydroperoxide at room temperature. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.02.031] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Mannam S, Alamsetti SK, Sekar G. Aerobic, Chemoselective Oxidation of Alcohols to Carbonyl Compounds Catalyzed by a DABCO-Copper Complex under Mild Conditions. Adv Synth Catal 2007. [DOI: 10.1002/adsc.200700213] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Jaseer EA, Naidu AB, Kumar SS, Rao RK, Thakur KG, Sekar G. Highly stereoselective chlorination of β-substituted cyclic alcohols using PPh3–NCS: factors that control the stereoselectivity. Chem Commun (Camb) 2007:867-9. [PMID: 17308658 DOI: 10.1039/b614512d] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A variety of trans-beta-substituted cyclic alcohols were stereoselectively chlorinated to either the corresponding cis-chloride or trans-chloride (inversion or retention of configuration) with good to excellent yields; the stereochemical outcome is determined by the size of the ring and the nature of the beta-substituents, especially the electronegativity of the substituted atom.
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Affiliation(s)
- E A Jaseer
- Department of Chemistry, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
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Kabilan L, Balasubramanian S, Keshava SM, Thenmozhi V, Sekar G, Tewari SC, Arunachalam N, Rajendran R, Satyanarayana K. Dengue disease spectrum among infants in the 2001 dengue epidemic in Chennai, Tamil Nadu, India. J Clin Microbiol 2003; 41:3919-21. [PMID: 12904418 PMCID: PMC179846 DOI: 10.1128/jcm.41.8.3919-3921.2003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An investigation in a referral pediatric hospital has indicated that during a recent dengue outbreak in Chennai, Tamil Nadu, India, dengue in infancy constituted 20% of total dengue virus infections with low mortality rates in this hospital. In developing countries, strengthening of dengue management capabilities at hospitals can prevent dengue-related deaths in infants.
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Affiliation(s)
- L Kabilan
- Centre for Research in Medical Entomology (Indian Council of Medical Research), Chinna Chokkikulam, Madurai 625 002, Chennai 600 034, India.
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Sekar G, Nishiyama H. Nonenzymatic kinetic resolution of secondary alcohols: enantioselective s(N)2 displacement of hydroxy groups by halogens in the presence of chiral BINAP. J Am Chem Soc 2001; 123:3603-4. [PMID: 11472136 DOI: 10.1021/ja010029i] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chandrasekhar M, Sekar G, Singh VK. An efficient method for opening nonactivated aziridines with TMS azide: application in the synthesis of chiral 1,2-diaminocyclohexane. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)01793-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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