Synergistic Effects of Arbuscular Mycorrhizal Fungi and Plant Growth Promoting Rhizobacteria for Sustainable Agricultural Production

Krishnamoorthy Ramasamy,Manoharan Melvin Joe,김기윤,이선미,Charlotte Shagol,Anandham Rangasamy1,정종배,Md. Rashedul Islam,사동민 한국토양비료학회 2011 한국토양비료학회지 Vol.44 No.4

Soil microorganisms play a major role in improving soil fertility and plant health. Symbiotic arbuscular mycorrhizal fungi (AMF) form a key component of the soil microbial populations. AMF form a mutualistic association with the host plant and exert a positive influence on its growth and nutrient uptake. The establishment of mycorrhizal symbioses with the host plant can positively be influenced by plant growth promoting rhizobacteria through various mechanisms such as increased spore germination and hyphal permeability in plant roots. Though there are evidences that combined interactions between AMF and PGPR can promote the plant growth however mechanisms of these interactions are poorly understood. Better understanding of the interactions between AMF and other microorganisms is necessary for maintaining soil fertility and enhancing crop production. This paper reviews current knowledge concerning the interactions between AMF and PGPR with plants and discusses on enhanced nutrient availability, biocontrol, abiotic stress tolerance and phytoremediation in sustainable agriculture.

Antibacterial Efficiency of Graphene Nanosheets against Pathogenic Bacteria via Lipid Peroxidation

Krishnamoorthy, Karthikeyan,Veerapandian, Murugan,Zhang, Ling-He,Yun, Kyusik,Kim, Sang Jae American Chemical Society 2012 The Journal of Physical Chemistry Part C Vol.116 No.32

<P>Graphene nanosheets are highly recognized for their utility toward the development of biomedical device applications. The present study investigated the antibacterial efficiency of graphene nanosheets against four types of pathogenic bacteria. Graphene nanosheets are synthesized by a hydrothermal approach (under alkaline conditions using hydrazine hydrate). UV–vis and X-ray diffraction show a maximum absorbance at 267 nm and appearance of new broad diffraction peak at 26°, which ensures the reduction of graphene oxide into graphene nanosheets. Stretching and bending vibrations of C–C bonds, chemical states, disorder, and defects associated with the graphene nanosheets are evaluated in comparison with graphene oxide. The minimum inhibitory concentration (MIC) of graphene nanosheets against pathogenic bacteria was evaluated by a microdilution method. MICs such as 1 μg/mL (against <I>Escherichia coli</I> and <I>Salmonella typhimurium</I>), 8 μg/mL (against <I>Enterococcus faecalis</I>), and 4 μg/mL (against <I>Bacillus subtilis</I>) suggest that graphene nanosheets have predominant antibacterial activity compared to the standard antibiotic, kanamycin. Measurement of free radical modulation activity of graphene nanosheets suggested the involvement of reactive oxygen species in antibacterial properties.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2012/jpccck.2012.116.issue-32/jp3047054/production/images/medium/jp-2012-047054_0008.gif'></P>

CRYOPRESERVATION OF SPERM AND ITS QUALITY ASSESSMENT IN COBIA, Rachycentron canadum

Krishnamoorthy Dhanasekar,Natesan Munuswamy 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5

k-OUT-OF-n-SYSTEM WITH REPAIR : T-POLICY

Krishnamoorthy, A.,Rekha, A. 한국전산응용수학회 2001 The Korean journal of computational & applied math Vol.8 No.1

We consider a k-out-of-n system with repair under T-policy. Life time of each component is exponentially distributed with parameter $\lambda$. Server is called to the system after the elapse of T time units since his departure after completion of repair of all failed units in the previous cycle or until accumulation of n-k failed units, whichever occurs first. Service time is assumed to be exponential with rate ${\mu}$. T is also exponentially distributed with parameter ${\alpha}$. System state probabilities in finite time and long run are derived for (i) cold (ii) warm (iii) hot systems. Several characteristics of these systems are obtained. A control problem is also investigated and numerical illustrations are provided. It is proved that the expected profit to the system is concave in ${\alpha}$ and hence global maximum exists.

Titanium carbide sheet based high performance wire type solid state supercapacitors

Krishnamoorthy, Karthikeyan,Pazhamalai, Parthiban,Sahoo, Surjit,Kim, Sang-Jae Royal Society of Chemistry 2017 Journal of Materials Chemistry A Vol.5 No.12

<P>Two dimensional sheets based on transition metal carbides have attracted much attention in electrochemical energy storage sectors. In this work, we demonstrated the fabrication and performance of titanium carbide based wire type supercapacitors (WSCs) towards next generation energy storage devices. The layered titanium carbide sheets were prepared<I>via</I>selective extraction of Al from the precursor Ti2AlC using hydrofluoric acid and are extensively characterized using X-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy, Fourier transform-infrared spectroscopy, and laser Raman spectral analyses, respectively. The X-ray photoelectron spectroscopy studies confirmed the presence of oxygen and fluorinated functional groups attached on the surface of titanium carbide. The electrochemical studies of the fabricated titanium carbide WSC devices showed ideal capacitive properties with a specific length capacitance of 3.09 mF cm<SUP>−1</SUP>(gravimetric capacitance of about 4.64 F g<SUP>−1</SUP>), and specific energy density of about 210 nW h cm<SUP>−1</SUP>(in length) or 315 mW h kg<SUP>−1</SUP>(in gravimetric) with excellent cycling stability. Further, a detailed examination of the capacitive and charge-transfer behavior of titanium carbide WSCs has been investigated<I>via</I>electrochemical impedance analysis using Nyquist and Bode plots. Additionally, we have also demonstrated the practical application of the titanium carbide WSCs, highlighting the path for their huge potential in energy storage and management sectors.</P>

Mechanistic investigation on the toxicity of MgO nanoparticles toward cancer cells

Krishnamoorthy, Karthikeyan,Moon, Jeong Yong,Hyun, Ho Bong,Cho, Somi Kim,Kim, Sang-Jae The Royal Society of Chemistry 2012 Journal of materials chemistry Vol.22 No.47

<P>Magnesium oxide nanoparticles (MgO NPs) are increasingly recognized for their applications in cancer therapy such as nano-cryosurgery and hyperthermia. The present study investigated the cytotoxic effects of magnesium oxide nanoparticles (MgO NPs) against normal lung fibroblast cells and different types of cancerous cells. MgO NPs exhibited a preferential ability to kill cancerous cells such as HeLa, AGS and SNU-16 cells. A detailed study has been undertaken to investigate the mechanism of cell death occurring in cancer cells (AGS cells) by the analysis of morphological changes, western blot analysis and flow cytometry measurements. Western blot analysis measurements suggested the role of apoptosis in cell death due to MgO exposure. MgO NPs enhanced ultrasound-induced lipid peroxidation in the liposomal membrane. Flow cytometry measurements using H<SUB>2</SUB>DCFDA showed that the toxicity of MgO NPs is attributed to the generation of reactive oxygen species, which further results in the induction of apoptosis in cancer cells. Our experimental results suggested the potential utility of MgO NPs in the treatment of cancer.</P> <P>Graphic Abstract</P><P>MgO nanoparticles exhibit an ability to kill cancer cells by inducing apoptosis through reactive oxygen species. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2jm35087d'> </P>

Mechanical energy harvesting properties of free-standing carbyne enriched carbon film derived from dehydrohalogenation of polyvinylidene fluoride

Krishnamoorthy, Karthikeyan,Mariappan, Vimal Kumar,Pazhamalai, Parthiban,Sahoo, Surjit,Kim, Sang-Jae Elsevier 2019 Nano energy Vol.59 No.-

<P><B>Abstract</B></P> <P>The development of functional materials towards mechanical energy harvesting applications is rapidly increasing during this decade. In this study, we are reporting the mechanical energy harvesting properties of free-standing carbyne-enriched carbon film (prepared via dehydrohalogenation of PVDF). Physico-chemical characterizations such as X-ray diffraction, Fourier-transformed infrared spectroscopy, X-ray photoelectron spectroscopy, <SUP>13</SUP>C NMR spectroscopy, and laser Raman spectral analyses confirmed the formation of the carbyne-enriched carbon film. The Raman mapping analysis revealed the homogeneous distribution of cumulenic (β-carbyne) networks in carbonoid matrix of the prepared film. The mechanical energy harvesting properties of carbyne-enriched carbon film have been examined under various applied compressive forces. The carbyne-enriched carbon film based energy harvester generates a peak to peak voltage of 6.48 V using a periodic force of 0.2 N, and the output voltage is directly proportional to the levels of applied compressive force. The carbyne-enriched carbon film based energy harvester possesses an instantaneous power density of about 72 nW cm<SUP>−2</SUP> with excellent electromechanical stability. These experimental findings ensure the use of carbyne-enriched carbon film as a mechanical energy harvester for the first time, which can create new insights towards the development of carbon-based mechanical energy harvesters.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dehydrohalogenation of PVDF into carbyne-enriched carbon film is obtained. </LI> <LI> Spectroscopic studies confirmed the conversion of PVDF carbyne-enriched carbon film. </LI> <LI> Raman mapping revealed the homogenous distribution of cumulene in the prepared film. </LI> <LI> Carbyne-enriched carbon film is explored as a novel mechanical energy-harvester. </LI> <LI> Mechanism of energy harvesting properties of carbyne-enriched carbon is discussed. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Structural optimization in practice: Potential applications of genetic algorithms

Krishnamoorthy, C.S. Techno-Press 2001 Structural Engineering and Mechanics, An Int'l Jou Vol.11 No.2

With increasing competition, the engineering industry is in need of optimization of designs that would lead to minimum cost or weight. Recent developments in Genetic Algorithms (GAs) makes it possible to model and obtain optimal solutions in structural design that can be put to use in industry. The main objective of this paper is to illustrate typical applications of GAs to practical design of structural systems such as steel trusses, towers, bridges, reinforced concrete frames, bridge decks, shells and layout planning of buildings. Hence, instead of details of GA process, which can be found in the reported literature, attention is focussed on the description of the various applications and the practical aspects that are considered in Genetic Modeling. The paper highlights scope and future directions for wider applications of GA based methodologies for optimal design in practice.

Impact of Environmental Factors and Altitude on Growth and Reproductive Characteristics of Teak (Tectona grandis Linn. f.) in Southern India

Krishnamoorthy, M.,Palanisamy, K.,Francis, A.P.,Gireesan, K. Institute of Forest Science 2016 Journal of Forest Science Vol.32 No.4

The effect of different environmental conditions and altitudes on the growth and reproductive characteristics in 12 teak plantations at 4 different blocks (Cauvery canal bank, Topslip and Parambikulam (Tamil Nadu), Nilambur and Wayanad (Kerala) of Southern India was investigated. The annual rainfall and mean monthly temperature of the study areas varied significantly from 1390 to 3188 mm and 16 to $38^{\circ}C$ respectively. The teak plantations in Cauvery canal bank which grow in continuous moisture condition (8-10 months) retain the leaf for longer period due to moisture resulting continuous supply of photosynthates leads to fast and outstanding growth. The girth at breast height (GBH) of 34-years-old tree in canal area was similar to that of 40 to 49-years-old trees in other locations, indicating that teak plantations with regular watering and silvicultural practices may be harvested at the age of 30 years. The leaf fall, flowering and fruiting showed significant variations in different teak plantations due to environmental factors and altitudes. It was found that increase of rainfall enhances number of flowers in the inflorescence in teak. Tholpatty (block-IV) showed more flowering in a inflorescence (3,734-3,744) compared to other plantations (1,678-3,307). Flowering in Nilambur and Wayanad coincided with heavy rainfall resulting low fruitset (1.1-2.3%) probably heavy rainfall ensuing restriction of pollinators for effective pollination. On the other hand, flowering in Cauvery canal bank (Block-I) was not coincided with high rainfall exhibited high fruitset (2-3%). About 66 to 76% of the fruits in different plantations were empty, and it is one of the main reasons for poor germination in teak. The seeds of Topslip and Parambikulam (Block-II) showed higher seed weight, maximum seed filling and good germination indicating that the environmental factors and altitude play significant role in fruit setting and seed filling in teak. In addition, the teak plantations in Topslip and Parambikulam showed good growth suggesting that plantations in the altitude range of approximately 550-700 m may be suitable for converting into seed production areas for production of quality seeds.

Designing two dimensional nanoarchitectured MoS₂ sheets grown on Mo foil as a binder free electrode for supercapacitors

Krishnamoorthy, K.,Veerasubramani, G.K.,Pazhamalai, P.,Kim, S.J. Pergamon Press 2016 ELECTROCHIMICA ACTA Vol.190 No.-

In this study, we demonstrated the preparation of nanoarchitectured MoS<SUB>2</SUB> sheets grown on Mo foil via hydrothermal method and examined its use as a binder free electrode for supercapacitors. The formation of well crystalline MoS<SUB>2</SUB> sheets on Mo foil was confirmed by laser Raman spectroscopy, Raman mapping, X-ray photoelectron spectroscopy, and field emission scanning electron microscopic analyses. The cyclic voltammetric studies suggested that the charge-storage mechanism in the MoS<SUB>2</SUB>/Mo electrodes is due to the contribution of combined pseudocapacitance with electrochemical double layer capacitance. The MoS<SUB>2</SUB>/Mo electrodes delivered a specific capacitance of about 192.7F/g from the galvanostatic charge-discharge analysis at a current density of 1mA/cm<SUP>2</SUP>. The experimental results suggested that the prepared MoS<SUB>2</SUB>/Mo binder free electrode will be a suitable candidate for electrochemical energy storage devices.