Phase, current, absorbance, and photoluminescence of double and triple metal ion-doped synthetic and salmon DNA thin films

Chopade, Prathamesh,Dugasani, Sreekantha Reddy,Kesama, Mallikarjuna Reddy,Yoo, Sanghyun,Gnapareddy, Bramaramba,Lee, Yun Woo,Jeon, Sohee,Jeong, Jun-Ho,Park, Sung Ha IOP Pub 2017 Nanotechnology Vol.28 No.40

<P>We fabricated synthetic double-crossover (DX) DNA lattices and natural salmon DNA (SDNA) thin films, doped with 3 combinations of double divalent metal ions (M<SUP>2+</SUP>)-doped groups (Co<SUP>2+</SUP>–Ni<SUP>2+</SUP>, Cu<SUP>2+</SUP>–Co<SUP>2+</SUP>, and Cu<SUP>2+</SUP>–Ni<SUP>2+</SUP>) and single combination of a triple M<SUP>2+</SUP>-doped group (Cu<SUP>2+</SUP>–Ni<SUP>2+</SUP>–Co<SUP>2+</SUP>) at various concentrations of M<SUP>2+</SUP> ([M<SUP>2+</SUP>]). We evaluated the optimum concentration of M<SUP>2+</SUP> ([M<SUP>2+</SUP>]<SUB>O</SUB>) (the phase of M<SUP>2+</SUP>-doped DX DNA lattices changed from crystalline (up to ([M<SUP>2+</SUP>]<SUB>O</SUB>) to amorphous (above [M<SUP>2+</SUP>]<SUB>O</SUB>)) and measured the current, absorbance, and photoluminescent characteristics of multiple M<SUP>2+</SUP>-doped SDNA thin films. Phase transitions (visualized in phase diagrams theoretically as well as experimentally) from crystalline to amorphous for double (Co<SUP>2+</SUP>–Ni<SUP>2+</SUP>, Cu<SUP>2+</SUP>–Co<SUP>2+</SUP>, and Cu<SUP>2+</SUP>–Ni<SUP>2+</SUP>) and triple (Cu<SUP>2+</SUP>–Ni<SUP>2+</SUP>–Co<SUP>2+</SUP>) dopings occurred between 0.8 mM and 1.0 mM of Ni<SUP>2+</SUP> at a fixed 0.5 mM of Co<SUP>2+</SUP>, between 0.6 mM and 0.8 mM of Co<SUP>2+</SUP> at a fixed 3.0 mM of Cu<SUP>2+</SUP>, between 0.6 mM and 0.8 mM of Ni<SUP>2+</SUP> at a fixed 3.0 mM of Cu<SUP>2+</SUP>, and between 0.6 mM and 0.8 mM of Co<SUP>2+</SUP> at fixed 2.0 mM of Cu<SUP>2+</SUP> and 0.8 mM of Ni<SUP>2+</SUP>, respectively. The overall behavior of the current and photoluminescence showed increments as increasing [M<SUP>2+</SUP>] up to [M<SUP>2+</SUP>]<SUB>O</SUB>, then decrements with further increasing [M<SUP>2+</SUP>]. On the other hand, absorbance at 260 nm showed the opposite behavior. Multiple M<SUP>2+</SUP>-doped DNA thin films can be used in specific devices and sensors with enhanced optoelectric characteristics and tunable multi-functionalities.</P>

EXPERIMENTAL INVESTIGATION USING CFD FOR THERMAL PERFORMANCE OF VENTILATED DISC BRAKE ROTOR

M. CHOPADE,A. VALAVADE 한국자동차공학회 2017 International journal of automotive technology Vol.18 No.2

In the present work, different ventilated disc brake rotor configurations were analysed to enhance the heat transfer rate and obtain the uniform temperature distribution in the rotor. CFD code used in this work was validated at using experimental results obtained by conducting experiments on a test rig. The experimental analysis was performed to calculate the mass flow rate and heat dissipation through the rotor. Further, different types of rotor configurations viz. straight radial vane (SRV), tapered radial vane (TRV), alternate long and short vane (ALSV), variable diameter circular pillars (VDCP) were considered for the analysis. A rotor segment of 20° was considered for the numerical analysis due to its rotational symmetry. CFD results were in good agreement with the experiments. The maximum deviation of the numerical results were about 12 % from the experimental results. It is found from the analysis that among the different types of rotor configurations; variable diameter circular pillars (VDCP) rotor gives better rate of heat dissipation with more uniform temperature distribution in the flow passages. Hence for modern high speed vehicles VDCP rotor may be more appropriate.

Enhanced functionalities of DNA thin films by facile conjugation with conducting polymers

Prathamesh Chopade,Sreekantha Reddy Dugasani,Sohee Jeong,Jun-Ho Jeong,Sung Ha Park 한국물리학회 2020 Current Applied Physics Vol.20 No.1

In this study, we discuss a method to embed PEDOT:PSS into DNA with a designated concentration of PEDOT:PSS and construction of PEDOT:PSS-embedded DNA thin films. In order to shed light on the interaction between PEDOT:PSS and DNA, optical spectroscopy measurements were performed. DNA-PEDOT:PSS thin films showed a broad absorption band around 800 nm which was associated with PEDOT:PSS. The electrical properties of DNA-PEDOT:PSS thin films were assessed. A significant enhancement in current for DNA-PEDOT:PSS thin films DNA was observed which agreed with the decrement in band gap of DNA-PEDOT:PSS thin films. For the energy storage capability and dielectric constant of DNA-PEDOT:PSS thin films, capacitance measurements were conducted. Frequency-dependent capacitance indicated enhancement in the capacitance and dielectric constant by electric polarization of PEDOT:PSS in a DNA thin film. Our approach may assist in development of various biosensors and electronic devices with specific functionalities based on biomaterials and conducting polymer complexes.

Opto-Electrical Properties of Marine Derived Porphyra-334 Mycosporine-Like Amino Acid

Ahn, Yongtae,Chopade, Prathamesh,Lee, Jeonghun,Kim, Hyoung-Shik,Seo, Hyo Hyun,Kanade, Vinit,Ansari, S. G.,Tongaonkar, Rucha,Park, Sung Ha,Kulkarni, Atul,Moh, Sang Hyun American Scientific Publishers 2018 Journal of nanoelectronics and optoelectronics Vol.13 No.3

<P>Mycosporine-like amino acids (MAAs) are metabolites produced by a variety of freshwater and marine organisms including bacteria, fungi, and algae. MAAs play an important role of photoprotection, i.e., protection of these organisms from harmful UV radiations. One of the MAAs, Porphyra-334 was subjected to study its opto electrical properties by Silicon nano-ribbon field effect transistor (FET) device and by cyclic voltammetry. SiNR and SP FET showed ambipolar characteristics. Porphyra-334 enhanced the photoconductivity of the SP FET. The electrochemical properties were described by cyclic voltammetry (CV) which supported the previous studies that Porphyra-334 is not an antioxidant and is oxidatively robust. The high electrochemical stability of the Porphyra-334 solution was demonstrated by the low current amplitude (mu A). Electrochemical Impedance spectroscopy was also performed. The Nyquist plot showed high resistance for Porphyra-334 under dark and illuminating conditions. These high resistance values demonstrate that within the solution, transport of Porphyra-334 molecules is slow, which indicates that Porphyra-334 molecules have good electrochemical stability.</P>

Content Based Dynamic Texture Analysis and Synthesis Based on SPIHT with GPU

Ghadekar, Premanand P.,Chopade, Nilkanth B. Korea Information Processing Society 2016 Journal of information processing systems Vol.12 No.1

Dynamic textures are videos that exhibit a stationary property with respect to time (i.e., they have patterns that repeat themselves over a large number of frames). These patterns can easily be tracked by a linear dynamic system. In this paper, a model that identifies the underlying linear dynamic system using wavelet coefficients, rather than a raw sequence, is proposed. Content based threshold filtering based on Set Partitioning in a Hierarchical Tree (SPIHT) helps to get another representation of the same frames that only have low frequency components. The main idea of this paper is to apply SPIHT based threshold filtering on different bands of wavelet transform so as to have more significant information in fewer parameters for singular value decomposition (SVD). In this case, more flexibility is given for the component selection, as SVD is independently applied to the different bands of frames of a dynamic texture. To minimize the time complexity, the proposed model is implemented on a graphics processing unit (GPU). Test results show that the proposed dynamic system, along with a discrete wavelet and SPIHT, achieve a highly compact model with better visual quality, than the available LDS, Fourier descriptor model, and higher-order SVD (HOSVD).

Content Based Dynamic Texture Analysis and Synthesis Based on SPIHT with GPU

( Premanand P. Ghadekar ),( Nilkanth B. Chopade ) 한국정보처리학회 2016 Journal of information processing systems Vol.12 No.1

Dynamic textures are videos that exhibit a stationary property with respect to time (i.e., they have patterns that repeat themselves over a large number of frames). These patterns can easily be tracked by a linear dynamic system. In this paper, a model that identifies the underlying linear dynamic system using wavelet coefficients, rather than a raw sequence, is proposed. Content based threshold filtering based on Set Partitioning in a Hierarchical Tree (SPIHT) helps to get another representation of the same frames that only have low frequency components. The main idea of this paper is to apply SPIHT based threshold filtering on different bands of wavelet transform so as to have more significant information in fewer parameters for singular value decomposition (SVD). In this case, more flexibility is given for the component selection, as SVD is independently applied to the different bands of frames of a dynamic texture. To minimize the time complexity, the proposed model is implemented on a graphics processing unit (GPU). Test results show that the proposed dynamic system, along with a discrete wavelet and SPIHT, achieve a highly compact model with better visual quality, than the available LDS, Fourier descriptor model, and higher-order SVD (HOSVD).

Morphological and Optoelectronic Characteristics of Double and Triple Lanthanide Ion-Doped DNA Thin Films

Kesama, Mallikarjuna Reddy,Dugasani, Sreekantha Reddy,Yoo, Sanghyun,Chopade, Prathamesh,Gnapareddy, Bramaramba,Park, Sung Ha American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.22

<P>Double and triple lanthanide ion (Ln(3+))-doped synthetic double crossover (DX) DNA lattices and natural salmon DNA (SDNA) thin films are fabricated by the substrate assisted growth and drop-casting methods on given substrates. We employed three combinations of double Ln(3+)-dopant pairs (Tb3+-Tm3+, Tb3+-Eu3+, and Tm3+-Eu3+) and a triple Ln3+-dopant pair (Tb3+-Tm3+-Eu3+) with different types of Ln3+, (i.e., Tb3+ chosen for green emission, Tm3+ for blue, and Eu3+ for red), as well as various concentrations of Ln(3+) for enhancement of specific functionalities. We estimate the optimum concentration of Ln(3+) ([Ln3+]O) wherein the phase transition of Ln(3+)-doped DX DNA lattices occurs from crystalline to amorphous. The phase change of DX DNA lattices at [Ln(3+)]O and a phase diagram controlled by combinations of [Ln(3+)] were verified by atomic force microscope measurement. We also developed a theoretical method to obtain a phase diagram by identifying a simple relationship between [Ln(3+)] and [Ln(3+)]O that in practice was found to be in agreement with experimental results. Finally, we address significance of physical characteristics-current for evaluating [Ln(3+)]O, absorption for understanding the modes of Ln(3+) binding, and photoluminescence for studying energy transfer mechanisms-of double and triple Ln(3+)-doped SDNA thin films. Current and photoluminescence in the visible region increased as the varying [Ln(3+)] increased up to a certain [Ln(3+)]O, then decreased with further increases in [Ln(3+)]. In contrast, the absorbance peak intensity at 260 nm showed the opposite trend, as compared with current and photoluminescence behaviors as a function of varying [Ln(3+)]. A DNA thin film with varying combinations of [Ln(3+)] might provide immense potential for the development of efficient devices or sensors with increasingly complex functionality.</P>

Characterization of Plant-Growth-Promoting Traits of Acinetobacter Species Isolated from Rhizosphere of Pennisetum glaucum

( Rokhbakhsh Zamin Farokh ),( Dhara Sachdev ),( Nadia Kazemi Pour ),( Anupama Engineer ),( Karishma R. Pardesi ),( Smita Zinjarde ),( Prashant K. Dhakephalkar ),( Balu A. Chopade ) 한국미생물 · 생명공학회 2011 Journal of microbiology and biotechnology Vol.21 No.6

A total of 31 Acinetobacter isolates were obtained from the rhizosphere of Pennisetum glaucum and evaluated for their plant-growth-promoting traits. Two isolates, namely Acinetobacter sp. PUCM1007 and A. baumannii PUCM1029, produced indole acetic acid (10-13 μg/ml). A total of 26 and 27 isolates solubilized phosphates and zinc oxide, respectively. Among the mineral-solubilizing strains, A. calcoaceticus PUCM1006 solubilized phosphate most efficiently (84 mg/ml), whereas zinc oxide was solubilized by A. calcoaceticus PUCM1025 at the highest solubilization efficiency of 918%. All the Acinetobacter isolates, except PUCM1010, produced siderophores. The highest siderophore production (85.0 siderophore units) was exhibited by A. calcoaceticus PUCM1016. Strains PUCM1001 and PUCM1019 (both A. calcoaceticus) and PUCM1022 (Acinetobacter sp.) produced both hydroxamate- and catechol-type siderophores, whereas all the other strains only produced catechol-type siderophores. In vitro inhibition of Fusarium oxysporum under iron-limited conditions was demonstrated by the siderophore-producing Acinetobacter strains, where PUCM1018 was the most potent inhibitor of the fungal phytopathogen. Acinetobacter sp. PUCM1022 significantly enhanced the shoot height, root length, and root dry weights of pearl millet seedlings in pot experiments when compared with controls, underscoring the plant-growth-promoting potential of these isolates.