De-Centralized Information Flow Control for Cloud Virtual Machines with Blowfish Encryption Algorithm

Gurav, Yogesh B.,Patil, Bankat M. International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.12

Today, the cloud computing has become a major demand of many organizations. The major reason behind this expansion is due to its cloud's sharing infrastructure with higher computing efficiency, lower cost and higher fle3xibility. But, still the security is being a hurdle that blocks the success of the cloud computing platform. Therefore, a novel Multi-tenant Decentralized Information Flow Control (MT-DIFC) model is introduced in this research work. The proposed system will encapsulate four types of entities: (1) The central authority (CA), (2) The encryption proxy (EP), (3) Cloud server CS and (4) Multi-tenant Cloud virtual machines. Our contribution resides within the encryption proxy (EP). Initially, the trust level of all the users within each of the cloud is computed using the proposed two-stage trust computational model, wherein the user is categorized bas primary and secondary users. The primary and secondary users vary based on the application and data owner's preference. Based on the computed trust level, the access privilege is provided to the cloud users. In EP, the cipher text information flow security strategy is implemented using the blowfish encryption model. For the data encryption as well as decryption, the key generation is the crucial as well as the challenging part. In this research work, a new optimal key generation is carried out within the blowfish encryption Algorithm. In the blowfish encryption Algorithm, both the data encryption as well as decryption is accomplishment using the newly proposed optimal key. The proposed optimal key has been selected using a new Self Improved Cat and Mouse Based Optimizer (SI-CMBO), which has been an advanced version of the standard Cat and Mouse Based Optimizer. The proposed model is validated in terms of encryption time, decryption time, KPA attacks as well.

One-pot exploitation of chitin biomass for simultaneous production of electricity, n-acetylglucosamine and polyhydroxyalkanoates in microbial fuel cell using novel marine bacterium <i>Arenibacter palladensis</i> YHY2

Gurav, Ranjit,Bhatia, Shashi Kant,Moon, Yu-Mi,Choi, Tae-Rim,Jung, Hye-Rim,Yang, Soo-Yeon,Song, Hun-Suk,Jeon, Jong-Min,Yoon, Jeong-Jun,Kim, Yun-Gon,Yang, Yung-Hun Elsevier 2019 JOURNAL OF CLEANER PRODUCTION Vol.209 No.-

<P><B>Abstract</B></P> <P>A novel marine bacterium <I>Arenibacter palladensis</I> YHY2 isolated from Eastern Sea, South Korea revealed hydrolysing ability of crab chitin in shake flask and microbial fuel cell (MFC) systems. Under shake flask cultivation, strain YHY2 demonstrated 71.44 ± 1.90 U/ml chitinase activity with the microbial cell optical density (OD) 0.699 ± 0.021. High performance liquid chromatography (HPLC) results showed N-acetylglucosamine (GlcNAc) as the major by-product of chitin degradation. Furthermore, <I>Ralstonia eutropha</I> H16 which has carbon utilization limited to GlcNAc and fructose was co-cultivated with YHY2 to consume GlcNAc and accumulate polyhydroxyalkanoates (PHA). However, on co-cultivating strain YHY2 with H16 surprisingly showed higher production of chitinase (97.89 ± 2.72 U/ml) and GlcNAc (80.31 mg GlcNAc/g chitin) corresponding to the microbial cell OD (1.065 ± 0.005) at 120 h. In addition, marine strain YHY2 demonstrated biofilm formation, hence co-cultivation of strain YHY2 and H16 under MFC system was performed to check the electricity production. Maximum electricity current output density was 15.15 μA/cm<SUP>2</SUP> at the initial stage and 10.72 μA/cm<SUP>2</SUP> at 204 h. GlcNAc (196.34 mg GlcNAc/g chitin) was produced along with other metabolites like butyrate, acetate, lactate, and propionate in MFC system. The microbial cell biomass from MFC was analysed for PHA content showed 1.020 g/l of 3-polyhydroxybutyrate (PHB) and 0.198 g/l of 3-polyhydroxyvalerate (PHV) as the main components of PHA. Moreover, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were performed to reveal changes in chitin before and after degradation. Thus, the exploitation of recalcitrant chitin biomass for simultaneous production of GlcNAc, electricity, and PHA in one-pot MFC system was the productive asset for sustainable development.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Coastal soil harbours <I>Arenibacter palladensis</I> YHY2 capable of hydrolysing chitin. </LI> <LI> YHY2 produced electricity in MFC using chitin biomass as a sole source of carbon. </LI> <LI> Co-cultivation of YHY2 with GlcNAc utilizing <I>Ralstonia eutropha</I> H16 accumulated PHA. </LI> <LI> First report on one-pot bioconversion of chitin into electricity, GlcNAc and PHA. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Room temperature chemical synthesis of Cu(OH)₂ thin films for supercapacitor application

Gurav, K.V.,Patil, U.M.,Shin, S.W.,Agawane, G.L.,Suryawanshi, M.P.,Pawar, S.M.,Patil, P.S.,Lokhande, C.D.,Kim, J.H. Elsevier Sequoia 2013 Journal of alloys and compounds Vol.573 No.-

Room temperature soft chemical synthesis route is used to grow nanograined copper hydroxide [Cu(OH)<SUB>2</SUB>] thin films on glass and stainless steel substrates. The structural, morphological, optical and wettability properties of Cu(OH)<SUB>2</SUB> thin films are studied by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV-vis spectrophotometer and water contact angle measurement techniques. The results showed that, room temperature chemical synthesis route allows to form the nanograined and hydrophilic Cu(OH)<SUB>2</SUB> thin films with optical band gap energy of 3.0eV. The electrochemical properties of Cu(OH)<SUB>2</SUB> thin films are studied in an aqueous 1M NaOH electrolyte using cyclic voltammetry. The sample exhibited supercapacitive behavior with 120F/g specific capacitance.

Silica Aerogel: Synthesis and Applications

Gurav, Jyoti L.,Jung, In-Keun,Park, Hyung-Ho,Kang, Eul Son,Nadargi, Digambar Y. Hindawi Publishing Corporation 2010 Journal of nanomaterials Vol.2010 No.-

<P>Silica aerogels have drawn a lot of interest both in science and technology because of their low bulk density (up to 95% of their volume is air), hydrophobicity, low thermal conductivity, high surface area, and optical transparency. Aerogels are synthesized from molecular precursors by sol-gel processing. Special drying techniques must be applied to replace the pore liquid with air while maintaining the solid network. Supercritical drying is most common; however, recently developed methods allow removal of the liquid at atmospheric pressure after chemical modification of the inner surface of the gels, leaving only a porous silica network filled with air. Therefore, by considering the surprising properties of aerogels, the present review addresses synthesis of silica aerogels by the sol-gel method, as well as drying techniques and applications in current industrial development and scientific research.</P>

Periodontitis and Insulin Resistance: Casual or Causal Relationship?

Abhijit N. Gurav 대한당뇨병학회 2012 Diabetes and Metabolism Journal Vol.36 No.6

Insulin resistance (IR) is now considered as a chronic and low level inflammatory condition. It is closely related to altered glucose tolerance, hypertriglyceridemia, abdominal obesity, and coronary heart disease. IR is accompanied by the increase in the levels of inflammatory cytokines like interleukin-1 and 6, tumor necrosis factor-α. These inflammatory cytokines also play a crucial part in pathogenesis and progression of insulin resistance. Periodontitis is the commonest of oral diseases, affecting tooth investing tissues. Pro-inflammatory cytokines are released in the disease process of periodontitis. Periodontitis can be attributed with exacerbation of IR. Data in the literature supports a “two way relationship” between diabetes and periodontitis. Periodontitis is asymptomatic in the initial stages of disease process and it often escapes diagnosis. This review presents the blurred nexus between periodontitis and IR, underlining the pathophysiology of the insidious link. The knowledge of the association between periodontitis and IR can be valuable in planning effectual treatment modalities for subjects with altered glucose homeostasis and diabetics. Presently, the studies supporting this association are miniscule. Further studies are mandatory to substantiate the role of periodontitis in the deterioration of IR.

Preparation of Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> absorber layers by electrodeposition of Cu/Zn/Sn metallic layers

K. V. Gurav,S. W. Shin,S. M. Pawar,P. S. Patil,J. H. Moon,J. H. Kim 한국신재생에너지학회 2013 한국신재생에너지학회 학술대회논문집 Vol.2013 No.05

Whole-cell Immobilization of Engineered Escherichia coli JY001 with Barium-alginate for Itaconic Acid Production

문유미,Ranjit Gurav,김준영,홍윤기,Shashi Kant Bhatia,장혜림,홍주원,최태림,양수연,박형연,주황수,양영헌 한국생물공학회 2018 Biotechnology and Bioprocess Engineering Vol.23 No.4

Itaconic acid is an important organic acid and a major component of various polymers. It is used in resins, superabsorbent polymers, and substitutes for petrochemicalbased monomers such as acrylic and methacrylic acids. Itaconic acid is primarily produced by the fungus Aspergillus terreus, which yields a high titer with albeit long fermentation period and by-products. In our previous study, Escherichia coli JY001 was reported to produce itaconic acid using citric acid in whole-cell reaction resulting in higher itaconic acid productivity with less by-products formation. The present study aimed to increase whole-cell enzyme stability and reusability, via immobilization of E. coli JY001 using barium-alginate beads. We optimized the cations, temperature, pH, alginate, BaCl2 concentration, cell density per bead, and CTAB content to improve transfer rate of substrates and products. Under the optimized conditions, immobilized whole cells were stable for four repeated cycles of itaconic acid production. The present results would strengthen the basis for a continuous itaconic acid production.

Band gap tunable and improved microstructure characteristics of Cu2ZnSn(S1-x,Sex)4 thin films by annealing under atmosphere containing S and Se

신승욱,In-YoungKim,GURAV KISHOR VISHWANATH,Chae Hwan Jeong,Jae Ho Yun,P.S. Patil,이정용,Jin Hyeok Kim 한국물리학회 2013 Current Applied Physics Vol.13 No.8

Cu2ZnSn(SxS1-x)4 (CZTSSe) thin films were prepared by annealing a stacked precursor prepared on Mo coated glass substrates by the sputtering technique. The stacked precursor thin films were prepared from Cu, SnS2, and ZnS targets at room temperature with stacking orders of Cu/SnS2/ZnS. The stacked precursor thin films were annealed using a tubular two zone furnace system under a mixed N2 (95%) þ H2S (5%) þ Se vaporization atmosphere at 580 ℃ for 2 h. The effects of different Se vaporization temperature from 250 C to 500 ℃ on the structural, morphological, chemical, and optical properties of the CZTSSe thin films were investigated. X-ray diffraction patterns, Raman spectroscopy, and X-ray photoelectron spectroscopy results showed that the annealed thin films had a single kesterite crystal structure without a secondary phase. The 2q angle position for the peaks from the (112) plane in the annealed thin films decreased with increasing Se vaporization temperature. Energy dispersive X-ray results showed that the presence of Se in annealed thin films increased from 0 at% to 42.7 at% with increasing Se vaporization temperatures. UVeVIS spectroscopy results showed that the absorption coefficient of all the annealed thin films was over 104 cm-1 and that the optical band gap energy decreased from 1.5 eV to 1.05 eV with increasing Se vaporization temperature.

Bath temperature impact on morphological evolution of Ni(OH)2 thin films and their supercapacitive behaviour

PATIL, U. M.,GURAV, K. V.,KIM, J. H.,LOKHANDE, C. D.,JUN, S. C. Indian Academy of Sciences 2014 Bulletin of materials science Vol.37 No.1

Nitrogen doped waste tea residue derived carbon dots for selective quantification of tetracycline in urine and pharmaceutical samples and yeast cell imaging application

Gunjal, Datta B.,Gurav, Yogesh M.,Gore, Anil H.,Naik, Vaibhav M.,Waghmare, Ravindra D.,Patil, Chandrashekhar S.,Sohn, Daewon,Anbhule, Prashant V.,Shejwal, Rajendra V.,Kolekar, Govind B. North-Holland 2019 Optical materials Vol.98 No.-

<P><B>Abstract</B></P> <P>In this work, waste tea residue, abundantly accessible, is utilized for synthesis of fluorescent carbon dots (CDs) by a simple, low cost and one step chemical oxidation method. The optical properties, surface functionality and particle size of CDs were ascertained by various techniques. The CDs exhibited excellent water solubility, optical properties, bioimaging ability etc. The fluorescence intensity of the CDs was diminished gradually with increasing concentrations of tetracycline drug owing to the inner filter effect (IFE) phenomenon. The developed fluorescent probe displayed a better linear range, excellent detection limit and interference free response to the tetracycline. This resulted in quantification of tetracycline in real sample which achieved almost 99% recoveries indicated excellent practical potential. Moreover, the CDs were used as fluorescent label for multicolour imaging of yeast cells which could open the doors for further research in biological fields.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carbon Dots derived from waste tea residue by simple reflux method. </LI> <LI> Determination of Tetracycline by fluorescence quenching through inner filter mechanism. </LI> <LI> Simple, sensitive and interference free method. </LI> <LI> Carbon dots as a fluorescent label for multicolour cell imaging. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Schematic of synthesis of CDs and inner filter effect based detection of tetracycline.</P> <P>[DISPLAY OMISSION]</P>