Free vibration analysis of rotating tapered blades using Fourier-p superelement

Gunda, Jagadish Babu,Singh, Anuj Pratap,Chhabra, Parampal Singh,Ganguli, Ranjan Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.27 No.2

A numerically efficient superelement is proposed as a low degree of freedom model for dynamic analysis of rotating tapered beams. The element uses a combination of polynomials and trigonometric functions as shape functions in what is also called the Fourier-p approach. Only a single element is needed to obtain good modal frequency prediction with the analysis and assembly time being considerably less than for conventional elements. The superelement also allows an easy incorporation of polynomial variations of mass and stiffness properties typically used to model helicopter and wind turbine blades. Comparable results are obtained using one superelement with only 14 degrees of freedom compared to 50 conventional finite elements with cubic shape functions with a total of 100 degrees of freedom for a rotating cantilever beam. Excellent agreement is also shown with results from the published literature for uniform and tapered beams with cantilever and hinged boundary conditions. The element developed in this work can be used to model rotating beam substructures as a part of complete finite element model of helicopters and wind turbines.

Methane as a Substrate for Energy Generation Using Microbial Fuel Cells

Kondaveeti, Sanath,Mohanakrishna, Gunda,Lee, Jung-Kul,Kalia, Vipin C. Springer-Verlag 2019 Indian journal of microbiology Vol.59 No.1

BODIPY-based Ru(II) and Ir(III) organometallic complexes of avobenzone, a sunscreen material: Potent anticancer agents

Gupta, Gajendra,Cherukommu, Shirisha,Srinivas, Gunda,Lee, Seon Woong,Mun, Sung Hwan,Jung, Jaehoon,Nagesh, Narayana,Lee, Chang Yeon Elsevier 2018 Journal of inorganic biochemistry Vol.189 No.-

<P><B>Abstract</B></P> <P>The use of organic compounds with known medicinal properties in the synthesis of metal-based complexes is an important alternative to improve the biological activity of metal-based drugs. The reaction of [M(<I>arene</I>)Cl<SUB>2</SUB>]<SUB>2</SUB> (M = Ru, arene = <I>p-cymene</I> and M = Ir, arene = pentamethylcyclopentadienyl, <I>cp*</I>) with avobenzone (1-(4-<I>tert</I>-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione, AVBH) and KOH in methanol leads to the formation of the neutral complexes [Ru(<I>p-cymene</I>)(AVB)Cl] <B>1</B> and [Ir(<I>cp*</I>)(AVB)Cl] <B>2</B> (<I>cp*</I> = pentamethylcyclopentadienyl). Subsequent reaction of <B>1</B> and <B>2</B> with pyridyl derivative-BODIPY ligands, BDP and BDPCC (BODIPY = boron dipyrromethene, BDP = 4-dipyridine boron dipyrromethene, BDPCC = 4-ethynylpyridine boron dipyrromethene) in methanol gives a series of four new dicationic supramolecules: [Ru<SUB>2</SUB>(<I>p-cymene</I>)<SUB>2</SUB>(AVB)<SUB>2</SUB>BDP][2CF<SUB>3</SUB>SO<SUB>3</SUB>] <B>3</B>, [Ir<SUB>2</SUB>(<I>cp*</I>)<SUB>2</SUB>(AVB)<SUB>2</SUB>BDP][2CF<SUB>3</SUB>SO<SUB>3</SUB>] <B>4</B>, [Ru<SUB>2</SUB>(<I>p-cymene</I>)<SUB>2</SUB>(AVB)<SUB>2</SUB>BDPCC][2CF<SUB>3</SUB>SO<SUB>3</SUB>] <B>5</B> and [Ir<SUB>2</SUB>(<I>cp*</I>)<SUB>2</SUB>(AVB)<SUB>2</SUB>BDPCC][2CF<SUB>3</SUB>SO<SUB>3</SUB>] <B>6</B>. The synthesized complexes are fully characterized using multiple analytical techniques, including elemental analysis, <SUP>1</SUP>H NMR, <SUP>13</SUP>C NMR, <SUP>19</SUP>F NMR (NMR = Nuclear Magnetic Resonance), Infrared Radiation (IR), Electrospray Ionization-Mass Spectrometry (ESI-MS), Ultraviolet-visible (UV–Vis) and fluorescence spectroscopy. The structures of these complexes are further rationalized using density functional theory (DFT) calculations. The antiproliferative activity of the neutral and dinuclear cationic complexes is evaluated in vitro in different human cancer cell lines. These complexes are found to be active against different cancer cell lines with half maximal inhibitory concentration (IC<SUB>50</SUB>) values between 1 and 5 μM. Complexes <B>5</B> and <B>6</B> displayed the lowest IC<SUB>50</SUB> values in all the cell lines studied. The activity of <B>5</B> and <B>6</B> is comparable to that of the well-known chemotherapy drug doxorubicin. Detailed biophysical studies indicate that complexes <B>5</B> and <B>6</B> exhibit very good Deoxyribonucleic acid (DNA) binding properties, causing the unwinding of the double helix, which is a probable reason for their high cytotoxicity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New bodipy-based Ru and Ir avobenzone complexes are reported. </LI> <LI> Physical and biological properties are studied in detail. </LI> <LI> Complexes 5 and 6 are more cytotoxic than 3 and 4. </LI> <LI> These complexes are also found to interact strongly with biomolecules. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Ruthenium and iridium supramolecules based on sunscreen molecule avobenzone and boron dipyrromethene (BODIPY) showing good anticancer properties are presented.</P> <P>[DISPLAY OMISSION]</P>

Evaluation of Anti-inflammatory and Regenerative Efficiency of Naringin and Naringenin in Degenerated Human Nucleus Pulposus Cells: Biological and Molecular Modeling Studies

Vijaya Madhuri Devraj,Satish Kumar Vemuri,Rajkiran Reddy Banala,Shravan Kumar Gunda,Gurava Reddy AV,Subbaiah GPV 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.6

Study Design: Development of an in vitro model for assessing the anti-inflammatory efficacies of naringin (Nar) and naringenin (NG). Purpose: To evaluate the efficacy of natural flavonoids as therapeutic drugs against anti-inflammatory processes in the nucleus pulposus (NP) cells using in-vitro and in-silico methods. Overview of Literature: Intervertebral disc (IVD) disease is a common cause of low back pain. Chronic inflammation and degeneration play a significant role in its etiopathology. Thus, a better understanding of anti-inflammatory agents and their role in IVD degeneration and pro-inflammatory cytokines expression is necessary for pain management and regeneration in IVD. Methods: We performed primary cell culture of NP cells; immunocytochemistry; gene expression studies of cytokines, metalloproteases, extracellular proteins, and apoptotic markers using quantitative polymerase chain reaction and reverse transcription-polymerase chain reaction (RT-PCR); cytotoxicity assay (MTT); and molecular docking studies using AutoDock 4.2 software (Molecular Graphics Laboratory, La Jolla, CA, USA) to confirm the binding mode of proteins and synthesized complexes. We calculated the mean±standard deviation values and performed analysis of variance and t -test using SPSS ver. 17.0 (SPSS Inc., Chicago, IL, USA). Results: Molecular docking showed that both Nar and NG bind to the selected genes of interest. Semi-quantitative RT-PCR analysis reveals differential gene expression of collagen (COL)9A1, COL9A2, COL9A3, COL11A2, COMT (catechol-O-methyltransferase), and THBS2 (thrombospondin 2); up regulation of ACAN (aggrecan), COL1A1, COL11A1, interleukin (IL)6, IL10, IL18R1, IL18RAP, metalloprotease (MMP)2, MMP3, MMP9, ADAMTS5 (a disintegrin and metalloproteinase with thrombospondin motifs 5), IGF1R (insulin-like growth factor type 1 receptor), SPARC (secreted protein acidic and cysteine rich), PARK2 (parkin), VDR (vitamin D receptor), and BCL2 (B-cell lymphoma 2); down regulation of IL1A, CASP3 (caspase 3), and nine genes with predetermined concentrations of Nar and NG. Conclusions: The present study evaluated the anti-inflammatory and regenerative efficiencies of Nar and NG in degenerated human NP cells. Altered gene expressions of cytokines, metalloproteases, extracellular proteins, apoptotic genes were dose responsive. The molecular docking (in silico ) studies showed effective binding of these native ligands (Nar and NG) with genes identified as potent inhibitors of inflammation. Thus, these natural flavonoids could serve as anti-inflammatory agents in the treatment of low back pain and sciatica.

Phenazine-1-carboxamide, an Extrolite Produced by Pseudomonas aeruginosa Strain (CGK-KS-1) Isolated from Ladakh and India, and its Evaluation Against Various Xanthomonas spp.

( K. Sirisha ),( C. Ganesh Kumar ),( Kallaganti Venkata Siva Ramakrishna ),( Shravan Kumar Gunda ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 한국미생물·생명공학회지 Vol.45 No.3

In the enduring investigation of the bioactive microbes, Pseudomonas aeruginosa strain (referred to as CGK-KS-1 (ICTB-315)), isolated from Chumathang hot spring, Ladakh, and India, was identified to possess a major bioactive fraction with antimicrobial and anti-biofilm properties. This bioactive metabolite was purified through bioactivity-guided fractionation. The chemical structure of this major compound was elucidated as phenazine-1-carboxamide (PCN) based on ¹H and ¹³C NMR, FT-IR, EI-HR-MS and 2D NMR spectroscopic techniques. In the current study, PCN exhibited antimicrobial activity with MIC values ranging between 1.9-3.9 μg/ml against various test human pathogens and Xanthomonas spp. PCN showed the antibiofilm property with the IC₅₀ values ranging from 17.04 to 60.7 μM against different test pathogens. The in silico docking studies showed PCN strongly interacted with various proteins of different Xanthomonas spp. with high binding energies. We report herein for the first time the anti-biofilm property and the docking studies of PCN. The extrolite from P. aeruginosa strain CGK-KS-1 showed promising bioactivities and may be considered as a potential candidate for application in various biocontrol strategies.

Inter-observer and intra-observer reliability between manual segmentation and semi-automated segmentation for carotid vessel wall volume measurements on three-dimensional ultrasonography

Chun Wai Chan,Sze Chai Christy Chow,Man Hei Kwok,Ka Ching Tiffany Ngan,Tsun Hei Or,Simon Takadiyi Gunda,Michael Ying 대한초음파의학회 2023 ULTRASONOGRAPHY Vol.42 No.2

Purpose: Carotid vessel wall volume (VWV) measurement on three-dimensional ultrasonography (3DUS) outperforms conventional two-dimensional ultrasonography for carotid atherosclerosis evaluation. Although time-saving semi-automated algorithms have been introduced, their clinical availability remains limited due to a lack of validation, particularly an extensive reliability analysis. This study compared inter-observer and intra-observer reliability between manual segmentation and semi-automated segmentation for carotid VWV measurements on 3DUS. Methods: Thirty-one 3DUS volume datasets were prospectively acquired from 20 healthy subjects, aged >18 years, without previous stroke, transient ischemic attack, or cardiovascular disease. Five observers segmented all volume datasets both manually and semi-automatically. The process was repeated five times. Reliability was expressed by the intraclass correlation coefficient, supplemented by the coefficient of variation. Results: Carotid VWV measurements using the common carotid artery (CCA) were more reliable than those using the internal carotid artery (ICA) or external carotid artery (ECA) for both manual and semiautomated segmentation (manual segmentation, CCA: inter-observer, 0.935; intra-observer, 0.934 to 0.966; ICA: inter-observer, 0.784; intra-observer, 0.756 to 0.878; ECA: inter-observer, 0.732; intraobserver, 0.919 to 0.962; semi-automated segmentation, CCA: inter-observer, 0.986; intra-observer, 0.954 to 0.993; ICA: inter-observer, 0.977; intra-observer, 0.958 to 0.978; ECA: inter-observer, 0.966; intra-observer, 0.884 to 0.937). Total carotid VWV measurements by manual (inter-observer, 0.922; intra-observer, 0.927 to 0.961) and semi-automated segmentation (inter-observer, 0.987; intra-observer, 0.968 to 0.989) were highly reliable. Semi-automated segmentation showed higher reliability than manual segmentation for both individual and total carotid VWV measurements. Conclusion: 3DUS carotid VWV measurements of the CCA are more reliable than measurements of the ICA and ECA. Total carotid VWV measurements are highly reliable. Semi-automated segmentation has higher reliability than manual segmentation.