Direct electrochemistry of cytochrome c with three-dimensional nanoarchitectured multicomponent composite electrode and nitrite biosensing

Shanmugasundaram, K.,Sai-Anand, G.,Gopalan, A.I.,Lee, H.G.,Yeo, H.K.,Kang, S.W.,Lee, K.P. Elsevier Sequoia 2016 Sensors and actuators. B Chemical Vol.228 No.-

A novel electrochemical nitrite ion (NO<SUB>2</SUB><SUP>-</SUP>) biosensor was designed and fabricated by modifying a glassy carbon electrode (GCE) into three-dimensional nanoarchitectured electrode (3DNE) using a multicomponent nanocomposite (MCNC) film composed of graphene embedded titanium dioxide nanowires (TiO<SUB>2</SUB>(G) NWs), thiol-functionalized polyaniline (PANI(SH)), gold nanoparticles (Au), and immobilized cytochrome c (cyt c). The new NO<SUB>2</SUB><SUP>-</SUP> biosensor was designated as cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE. The assembly of the 3DNE, involved sequential depositions of PANI(SH) and Au over previously synthesized TiO<SUB>2</SUB>(G) NWs by electrospinning-hydrothermal processes and immobilization of the cyt c onto the TiO<SUB>2</SUB>(G) NWs/PANI(SH)/Au MCNC film. The cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE exhibited direct electron transfer from cyt c to the electrode at a high rate constant (25.34s<SUP>-1</SUP>). The fabricated cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE showed high selectivity to NO<SUB>2</SUB><SUP>-</SUP> ions with excellent sensitivity (9.2μA/mM), a wide linear concentration range (10μM-720mM), and a low detection limit (0.05μM). Additionally, the cyt c/TiO<SUB>2</SUB>(G) NWsΠANI(SH)-Au MCNC/3DNE exhibited high stability with good reproducibility and repeatability.

The Relationship between Growth Duration and Yield in Soybean in the Sub-tropics

Kim S. D.,T. S. Toung,S. Shanmugasundaram 한국작물학회 1983 한국작물학회지 Vol.28 No.4

아열대 지역의 콩생육기간과 수량과의 관계

Kim S. D.,T. S. Toung,S. Shanmugasundaram 韓國作物學會 1983 한국작물학회지 Vol.28 No.4

아열대 지역에서의 콩생육기간과 수량과의 관계를 구명하고자 1981년 대만 소재 아세아 채소연구개발센터(AVRDC)에서 선발한 콩 482계통을 봄, 여름, 가을 작기에 동일재료를 공시 생산력시험을 실시하여 얻은 결과를 요약하면 다음과 같다. 1. 작기별 평균수량 및 최고수량은 봄작기에서 높았고 가을, 여름 순으로, 낮았으며 가을 작기에서 계통간의 수량차가 제일 적었다. 2. 콩 수량은 작기에 관계없이 생육일수가 증가됨에 따라 증가되었으나 개화일수가 길어짐에 따라 수량은 감소되었다. 3. 100립중은 작기에 관계없이 결실기간이 길수록 무거운 경향을 보였으며 여름과 가을 작기에서 그 관계가 유의적이었다. 4. 다중회귀분석 결과 봄, 여름, 가을 어느 작기에서나 개화일수는 짧고 결실기간이 상대적으로 긴 계통이 고위생산력을 보이는 계통으로 고려되었다. Seasonal variations influence the growth duration and yield of soybeans in the tropics and subtropics. Results of different yield trials were used to determine the relationship between yield with days to R1 and R8 in different seasons. Similarly relationship for 100 seed weight was examined. Multiple regression equations suggest that increase in yield can be obtained by increasing the days to R8 regardless of seasons. However, increasing the days to R1 invariably reduced the yield. The longer the time from R1 to R8 , the higher the 100 seed weight. Since the population examined was heterogeneous for photoperiod sensitivity, the need to examine photoperiod sensitive and insensitive selections separately is discussed.

Synthesis and photophysical characterization of an ionic fluorene derivative for blue light-emitting electrochemical cells

Shanmugasundaram, K.,Subeesh, M.S.,Sunesh, C.D.,Chitumalla, R.K.,Jang, J.,Choe, Y. Elsevier Science 2015 ORGANIC ELECTRONICS Vol.24 No.-

A highly fluorescent an ionic fluorene derivative 1 was synthesized and its photophysical, electrochemical and electroluminescence characteristics were investigated. Deep blue emissions were observed for compound 1 in solid as well as in dilute solutions. The synthesized compound shows high fluorescence quantum yield around 77% indicates that compound 1 can perform its role as efficient ionic emitter in LEC devices. Light-emitting electrochemical cell (LEC) devices were fabricated incorporating compound 1 without (device I) and with (device II) ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM.PF<SUB>6</SUB>). Devices I and II exhibited blue electroluminescence maximum centered at 455 and 454nm with CIE coordinates of (0.15, 0.21) and (0.16, 0.22), respectively. Maximum luminance and current efficiency of 1105cdm<SUP>-2</SUP> and 0.14cdA<SUP>-1</SUP> respectively, has achieved for device I while that of device II resulted in 1247cdm<SUP>-2</SUP> and 0.14cdA<SUP>-1</SUP> respectively.

Photophysical, electrochemical, and quantum chemical properties of cationic iridium complexes with tunable emission color

Sunesh, C.D.,Chitumalla, R.K.,Subeesh, M.S.,Shanmugasundaram, K.,Jang, J.,Choe, Y. Elsevier S.A 2016 Journal of Electroanalytical Chemistry Vol.780 No.-

<P>We report the synthesis and characterization of the cationic iridium complexes [Ir(ppy)(2)(mPoxd)]PF6 (1), [Ir(dfppy)(2)(mpoxd)]PF6 (2), [Ir(piq)(2)(mpoxd)]PF6 (3), and [Ir(pq)(2)(mpoxd)]PF6 (4) bearing 2-phenylpyridine (Hppy), 2-(2,4-difluorophenyl)pyridine (Hdfppy), 1-phenylisoquinoline (Hpiq), and 2-phenylquinoline (Hpq) as cyclometalating ligands and 5-methyl-3-(2-pyridyl)-1,2,4-oxadiazole (mpoxd) as an ancillary ligand. UV-visible absorption spectra, photoluminescence (PL) emission spectra, and cyclic voltammetric measurements were obtained to explore the photophysical and electrochemical properties of 1-4. Depending on the nature of the cyclometalating ligands, the complexes emit yellow-orange to blue light in acetonitrile solution at room temperature. The significant blue shift in the emission spectrum of 2 is due to the presence of electron-withdrawing fluorine atoms on Hdfppy, which stabilizes the highest occupied molecular orbital (HOMO) to a greater extent than in the other complexes. The electrochemical and photophysical properties of the complexes were also calculated using density functional theory (DFT) and time-dependent DFT simulations. The results indicate that the optical properties of the complexes can be effectively tuned by selective design of the cyclometalating and ancillary ligands. (C) 2016 Elsevier B.V. All rights reserved.</P>

Proximal fibular osteotomy in the treatment of medial osteoarthritis of the knee - A narrative review of literature

( Saseendar Shanmugasundaram ),( Srinivas B. S. Kambhampati ),( Samundeeswari Saseendar ) 대한슬관절학회 2019 대한슬관절학회지 Vol.31 No.1

Proximal fibular osteotomy has been proposed as a simple and inexpensive alternative to high-tibial osteotomy and unicondylar knee arthroplasty and may be useful for low-income populations that cannot afford expensive treatment methods. However, there is no consensus existing regarding the mechanism by which it acts nor the outcome of this procedure. This study was performed to analyze the available evidence on the benefits of proximal fibular osteotomy and to understand the possible mechanisms in play. There are various mechanisms that are proposed to individually or collectively contribute to the outcomes of this procedure, and include the theory of non-uniform settlement, the too-many cortices theory, slippage phenomenon, the concept of competition of muscles, dynamic fibular distalization theory and ground reaction vector readjustment theory. The mechanisms have been discussed and future directions in research have been proposed. The current literature, which mostly consists of case series, suggests the usefulness of the procedure in decreasing varus deformity as well as improving symptoms in medial osteoarthritis. However, large randomised controlled trials with long-term follow-up are required to establish the benefits of this procedure over other established treatment methods.

Piezoresistive sensor-integrated PDMS cantilever: A new class of device for measuring the drug-induced changes in the mechanical activity of cardiomyocytes

Kim, D.S.,Jeong, Y.J.,Lee, B.K.,Shanmugasundaram, A.,Lee, D.W. Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.240 No.-

Herein, we demonstrate in detail the fabrication and evaluation procedure of a piezoresistive sensor-integrated polydimethylsiloxane (PDMS) cantilever for measuring the drug-induced changes in the contraction force of cardiomyocytes. The proposed device consists of a glass body with metal patterns, a PDMS cantilever with microgrooves (μgrooves), and integrated piezoresistive sensor. Reliability of the piezoresistive sensor and connection wires was greatly improved by using a glass substrate with metal patterns. The longitudinally patterned μgrooves formed on the PDMS cantilever was optimized to maximize cantilever deformation. The mechanical deformation of the cantilever caused by the contraction force of cardiomyocytes is directly observed by using the integrated piezoresistive sensor, whereas the existing methods rely on the optical methods to measure the cantilever displacement. The contraction force is maximized between day eight and nine after seeding the cardiomyocytes onto the PDMS cantilever. After preliminary experiments, the strain sensor integrated μpatterned PDMS cantilever was subjected to measure the change in the contraction force of cardiomyocytes under different concentrations of cardiac drugs. The experimental results showed that the strain sensor integrated PDMS cantilever can effectively verify the changes in the mechanical output of the cardiomyocytes under the drug influence.

A Simple Method of Seedling Screening for Drought Tolerance in Soybean

Young-Jin Kim,S. Shanmugasundaram,Song-Joong Yun,Ho-Ki Park,Moon-Soo Park 韓國作物學會 2001 Korean journal of crop science Vol.46 No.4

Water deficit is a serious constraint to soybean [Glycine max L. (Merr.)] production in rainfed regions of Asia, Africa, and America. This study was conducted to develop a simple and effective screening method for drought tolerance in soybean. Fifteen soybean cultivars, eight identified to be drought-tolerant and seven drought-sensitive in previous studies, were used for the evaluation of drought tolerance under the new screening conditions. The seedling screening method was consisted of a treatment in a PEG solution and drought treatment in parafilm-layered pots. 5-day-old seedlings were treated in a 18% PEG solution for 4 days and their wilting and hypocotyl browning were recorded. Three seedlings grown in a parafilm-layered pot containing peat moss were drought-stressed by withholding water from the third day after seedling emergence, and root and seedling growth were examined. Degree of drought tolerance were rated based on seedling vigor in the PEG solution and drought-stressed parafilm-layered pots, and also on the penetration ability of roots through parafilm layer. Most of seedlings of the drought-tolerant cultivars showed higher vigour and root penetration than those of the drought-sensitive cultivars under the new screening conditions. Our results indicate that the new method can be used as a simple and effective screening procedure for drought tolerance in soybean breeding programs.

A SVPWM Control Strategy for Capacitor Voltage Balancing of Flying Capacitor Based 4-Level NPC Inverter

R. Palanisamy,V. Shanmugasundaram,S. Vidyasagar,V. Kalyanasundaram,K. Vijayakumar 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.6

A Space Vector Pulse Width Modulation (SVPWM) control strategy is implemented for capacitor voltage balancing of Flying Capacitor (FC) based 4-level Neutral Point Clamped (NPC) inverter. This fl ying capacitor based 4-level NPC inverter is developed for medium voltage and high power applications. This system includes 6 power switching devices, 2 clamping diodes and 2 fl ying capacitors per leg. The fl ying capacitors ensure to operate inverter normally and all the switching devices share the voltage stresses in identical manner. Also it controls the voltage across each capacitor and maintained at V dc /3 times of applied dc voltage. The proposed SVPWM method takes advantage of utilizing redundancy switching states to control and balance the voltage across the capacitor using nearest switching state vector selection method. Moreover, this system provides reduced total harmonic distortion (THD), and minimized voltage stress. The control technique is implemented without using any look-up tables or eff ective logic tables or trigonometric functions. The simulation and experimental results of this proposed verifi ed are verifi ed using Matlab-simulink and FPGA controller respectively.

Selection of New Breeding Materials with Resistance to Anthracnose in Capsicum annuum

Do-Ham Pae,Young Chae,Tien-Chen Wang,Liwayway M. Engle,S. Shanmugasundaram 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-