Purification of Escherichia coli Ribosome by Strong Anion Exchange Spin Columns

Iyappan KATHIRVEL,Jihyun YU,Taek Jin KANG 한국생물공학회 2023 한국생물공학회 학술대회 Vol.2023 No.10

Corrosion resistance of mild steel in sulphuric acid solution by <i>Coreopsis tinctoria</i> extract: electrochemical and surface studies

Kalaiselvi, Kathirvel,Chung, Ill-Min,Kim, Seung-Hyun,Prabakaran, Mayakrishnan Emerald (MCB UP ) 2018 Anti-corrosion methods and materials Vol.65 No.4

Probabilistic modeling of geopolymer concrete using response surface methodology

Parthiban Kathirvel,Saravana Raja Mohan Kaliyaperumal 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.19 No.6

Geopolymer Concrete is typically proportioned with activator solution leading to moderately high material cost. Such cost can be enduring in high value added applications especially when cost savings can be recognized in terms of reduction in size of the members. Proper material selection and mix proportioning can diminish the material cost. In the present investigation, a total of 27 mixes were arrived considering the mix parameters as liquid-binder ratio, slag content and sodium hydroxide concentration to study the mechanical properties of geopolymer concrete (GPC) mixes such as compressive strength, split tensile strength and flexural strength. The derived statistical Response Surface Methodology is beleaguered to develop cost effective GPC mixes. The estimated responses are not likely to contrast in linear mode with selected variables; a plan was selected to enable the model of any response in a quadratic manner. The results reveals that a fair correlation between the experimental and the predicted strengths.

Transparent and flexible carbon dots/polymer scaffold for deep UV photodetection applications

Gopi Pavithra,Ponnusamy Kathirvel 한국탄소학회 2023 Carbon Letters Vol.33 No.4

This work reports the fabrication of a flexible Photodetector (PD) using Carbon Dots (CDs)/Polymer composite for Deep UV (DUV) photodetection. The CDs have been prepared using a simple and inexpensive heating process. The syncretic studies reveal the disordered graphitic core with surface functional groups and the excitation-dependent character of CDs. The synthesized CDs are stabilized via Poly Vinyl Alcohol (PVA) through a synergistic effect and investigated for different compositions (2–10 weight %) of CDs. The CDs/PVA composites shows improved absorbance at 208 and 335 nm compared to pure CDs owing to the bonding between them. This advantageous property of high absorption and photo response in the DUV region is utilized by employing CDs/PVA composite as a photo-sensing layer on the ITO-coated PET substrate in the PD. The performance of the PD was measured under dark, short (254 nm) and long (365 nm) UV region. Among all the compositions, 4% CDs/PVA PD exhibits superior performance in terms of high photo-to-dark current ratio (IPh/Id), responsivity and detectivity. The PD functioning and other parameters are discussed in detail and reported.

Feasibility Study of Deep Inspiration Breath-Hold Based Volumetric Modulated Arc Therapy for Locally Advanced Left Sided Breast Cancer Patients

Swamy, Shanmugam Thirumalai,Radha, Chandrasekaran Anu,Kathirvel, Murugesan,Arun, Gandhi,Subramanian, Shanmuga Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: The purpose of this study was to assess the feasibility of deep inspiration breath-hold (DIBH) based volumetric modulated arc therapy (VMAT) for locally advanced left sided breast cancer patients undergoing radical mastectomy. DIBH immobilizes the tumor bed providing dosimetric benefits over free breathing (FB). Materials and Methods: Ten left sided post mastectomy patients were immobilized in a supine position with both the arms lifted above the head on a hemi-body vaclock. Two thermoplastic masks were prepared for each patient, one for normal free breathing and a second made with breath-hold to maintain reproducibility. DIBH CT scans were performed in the prospective mode of the Varian real time position management (RPM) system. The planning target volume (PTV) included the left chest wall and supraclavicular nodes and PTV prescription dose was 5000cGy in 25 fractions. DIBH-3DCRT planning was performed with the single iso-centre technique using a 6MV photon beam and the field-in-field technique. VMAT plans for FB and DIBH contained two partial arcs ($179^{\circ}-300^{\circ}CCW/CW$). Dose volume histograms of PTV and OAR's were analyzed for DIBH-VMAT, FB-VMAT and DIBH-3DCRT. In DIBH mode daily orthogonal ($0^{\circ}$ and $90^{\circ}$) KV images were taken to determine the setup variability and weekly twice CBCT to verify gating threshold level reproducibility. Results: DIBH-VMAT reduced the lung and heart dose compared to FB-VMAT, while maintaining similar PTV coverage. The mean heart $V_{30Gy}$ was $2.3%{\pm}2.7$, $5.1%{\pm}3.2$ and $3.3%{\pm}7.2$ and for left lung $V_{20Gy}$ was $18.57%{\pm}2.9$, $21.7%{\pm}3.9$ and $23.5%{\pm}5.1$ for DIBH-VMAT, FB-VMAT and DIBH-3DCRT respectively. Conclusions: DIBH-VMAT significantly reduced the heart and lung dose for left side chest wall patients compared to FB-VMAT. PTV conformity index, homogeneity index, ipsilateral lung dose and heart dose were better for DIBH-VMAT compared to DIBH-3DCRT. However, contralateral lung and breast volumes exposed to low doses were increased with DIBH-VMAT.

Evaluation of Composite Cements using Cyclic Polarization Techniques

V. Saraswathy,S. Muralidharan,L. Balamurugan,P. Kathirvel,A. S. S. Sekar 대한토목학회 2011 KSCE JOURNAL OF CIVIL ENGINEERING Vol.15 No.8

Slag Cement (PSC) extracts in the presence and absence of nitrite inhibitor were studied by cyclic polarization technique. Studies also carried out in composite (binary and ternary) cement extracts. The re-passivation potential (Erep) is an important parameter to characterize the corrosion resistant property of cements and the efficiency of inhibitor. Blended cements (PPC and PSC) have higher tolerable limit of chloride than OPC. Binary cements increase the tolerable limit of chloride than individual cements. The passivity of steel maintained by ternary cement was found to be less than 45000 ppm of chloride along with 5000 ppm of nitrite (pitting occurred at 45000 ppm). This chloride level is more than that of chlorides in natural sea water (35000 ppm). Hence the use of composite cement especially in marine atmosphere increases the corrosion resistance of steel in concrete.

Microstructure Characteristics of Fly Ash Concrete with Rice Husk Ash and Lime Stone Powder

Sang-Hwa Jung,Velu Saraswathy,Subbiah Karthick,Palanivel Kathirvel,Seung-Jun Kwon 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.2

Industrial wastes and recycled materials are being utilized in the construction industry for preserving the environment, saving of materials, and enhancing durability of the construction material. Blending of cement with supplementary cementitious materials like fly ash, rice husk ash, and silica fume makes concrete more durable. The main objective of this study is to make use of the rice husk ash and lime powder (LP) as a replacement of Portland pozzolana cement considering various replacement levels. The engineering and durability performance in concrete with LP were performed through compressive strength and void measurement. The microstructure in the concrete with LP was characterized through XRD, SEM/EDS, and TG/DTA. Optimum replacement ratio for rice husk ash and LP were obtained through pozzolanic reaction based CSH formation.

<i>Polygonatum odaratum</i> extract as an eco-friendly inhibitor for aluminum corrosion in acidic medium

Prabakaran, Mayakrishnan,Kim, Seung-Hyun,Sasireka, Asokan,Kalaiselvi, Kathirvel,Chung, Ill-Min VNU Science Press 2018 Journal of Adhesion Science and Technology Vol. No.

<P>The corrosion of aluminum specimens in Polygonatum odaratum (P. odaratum) extract was studied using weight loss measurements, potentiodynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy (SEM), and electron dispersive X-ray spectroscopy (EDX) techniques. The inhibition efficiency of the aluminum specimens in the presence of inhibitor from P. odaratum plant extract at 303-333 +/- 1 K was evaluated with the weight loss technique. The results indicate the inhibition efficiency of P. odaratum plant extract increased with increased concentration of the inhibitor and decreased temperature in an acidic medium. The corrosion inhibition properties of the P. odaratum plant extract for aluminum specimen corrosion in 1 M HCl were analyzed using polarization studies and electrochemical impedance studies, which clearly showed a mixed-type inhibitor. UV-visible spectroscopy, Fourier transform infrared (FT-IR), SEM, and EDX revealed the surface morphology in the presence and absence of inhibitor on the metal surface. The results indicated the feasibility of using the P. odaratum plant extract as a corrosion inhibitor in acid environments.</P>

Bioprospecting Endophytic Fungi and Their Metabolites from Medicinal Tree Aegle marmelos in Western Ghats, India

( Vellingiri Manon Mani ),( Arockiamjeyasundar Parimala Gnana Soundari ),( Damodharan Karthiyaini ),( Kathirvel Preethi ) 한국균학회 2015 Mycobiology Vol.43 No.3

The increasing emergence of lead drugs for the resistance produced by the pathogenic strains and arrival of new diseases have initiated the need for searching novel metabolites with best anticancer and antimicrobial properties than the existing one. With this view, the investigation was conducted for the isolation, identification, and biological evaluation of potential endophytic fungi of Aegle marmelos, a medicinal tree used for more than three decades, for curing various disorders. A total of 169 endophytic fungal strains obtained from sampling and among those 67 were pigmented strains. Upon antagonistic screening, five endophytic fungal strains exhibited antagonistic potentiality by inhibiting the pathogens. These five potent strains were characterized at molecular level by sequencing the amplified internal transcribed spacer (ITS) 1 and ITS 4 regions of rDNA and they were grouped under order Pleosporales, Eurotiales, and Capnodiales. The metabolites from the respective strains were produced in fungal culturing media and extracted using polar solvents. Further, the extracts of five endophytes manifested antimicrobial activity against tested clinical pathogens and Alternaria alternata (FC39BY), Al. citrimacularis (FC8ABr), and Curvularia australiensis (FC2AP) exhibited significant antimicrobial profile against 9 of 12 tested pathogens, showing broad spectrum activity. The antioxidant levels of all the five endophytes revealed the highest activity at least concentrations, and major activity was unveiled by the members of order Pleosporales FC2AP and FC8ABr. This research explains the value of endophytic fungal extracts and its significance of antimicrobial and antioxidant properties.

Google Search Trends Predicting Disease Outbreaks: An Analysis from India

Madhur Verma,Kamal Kishore,Mukesh Kumar,Aparajita Ravi Sondh,Gaurav Aggarwal,Soundappan Kathirvel 대한의료정보학회 2018 Healthcare Informatics Research Vol.24 No.4

Objectives: Prompt detection is a cornerstone in the control and prevention of infectious diseases. The Integrated Disease Surveillance Project of India identifies outbreaks, but it does not exactly predict outbreaks. This study was conducted to assess temporal correlation between Google Trends and Integrated Disease Surveillance Programme (IDSP) data and to determine the feasibility of using Google Trends for the prediction of outbreaks or epidemics. Methods: The Google search queries related to malaria, dengue fever, chikungunya, and enteric fever for Chandigarh union territory and Haryana state of India in 2016 were extracted and compared with presumptive form data of the IDSP. Spearman correlation and scatter plots were used to depict the statistical relationship between the two datasets. Time trend plots were constructed to assess the correlation between Google search trends and disease notification under the IDSP. Results: Temporal correlation was observed between the IDSP reporting and Google search trends. Time series analysis of the Google Trends showed strong correlation with the IDSP data with a lag of –2 to –3 weeks for chikungunya and dengue fever in Chandigarh (r > 0.80) and Haryana (r > 0.70). Malaria and enteric fever showed a lag period of –2 to –3 weeks with moderate correlation. Conclusions: Similar results were obtained when applying the results of previous studies to specific diseases, and it is considered that many other diseases should be studied at the national and sub-national levels.