Fe₃O₄ Nanoparticle-mediated Hydrogen Fermentation for the Conversion of Potato Waste Biomass by Thermophilic Parageobacillus thermoglucosidasius Strain

Mamata SINGHVI,Anoth MAHARJAN,Beom Soo KIM 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

In this study, starch-based potato peel waste biomass (PWB) was used for hydrogen production through dark fermentation by the thermophillic amylase producing strain Parageobacillus thermoglucosidasius KCTC 33548. The effect of magnetic Fe₃O₄ nanoparticles (NPs) on hydrogen production from pure starch and starch-based PWB was experimentally studied and confirmed by kinetic analysis. The supplementation of optimized concentrations of both Fe₃O₄ NPs (300 ㎎/L) and L-cysteine (250 ㎎/L) during hydrogen fermentation using pure starch and PWB generated maximum cumulative hydrogen yields of 167 and 71.9 mL with maximum production rates of 2.81 and 1.26 mL/h, respectively. Further, the correlation between Fe₃O₄ and the expression of hydrogenase isoforms and the related hydrogenase activity was explored. Higher hydrogenase activity was obtained in the membrane-associated fractions (3.67 U/㎎ of protein) of cells grown in the presence of Fe₃O₄. Zymogram analysis exhibited two additional isoforms (Hyd 1 and Hyd 2) in fermented broth containing Fe₃O₄ NPs indicating the role of Fe ions in expression of hydrogenase isoforms.

Slot Exchange Algorithm for Real-time Communication in Synchronous Ad hoc Network

Mamata Koirala,Jaeho Choi 대한전자공학회 2007 ITC-CSCC :International Technical Conference on Ci Vol.2007 No.7

The flexible nature of ad hoc network provides much challenge for the researchers. In this paper we have investigated a time-slot management problem occurring in time-division multiplexing based real-time communications such as voice calls over the ad hoc network. Due to node mobility the network topology frequently changes, and managing the time synchronization and addressing the time slot ownership among the active nodes are challenging issues. In this paper a novel time-slot exchange protocol (SEP) for real-time communications in a synchronous ad hoc network is present. The approach to find the free time slot and to replace it with current one is focus of our investigation. Our method effectively alleviates multiple ownerships claimed over a single time-slot and successfully maintains a lower call breakage rate. The proposed SEP algorithm have applied to support voice communications using IEEE 802.11b; and the simulations are performed using OPNET modeler in terms of packet loss rate and delay.

New transitivity property of intuitionistic fuzzy multiplicative preference relation and its application in missing value estimation

Mamata Sahu,Anjana Gupta 원광대학교 기초자연과학연구소 2018 ANNALS OF FUZZY MATHEMATICS AND INFORMATICS Vol.16 No.1

In the decision-making process, consistency is a crucial issue which causes wide public concern of exports. The lack of consistency in preference relations results in an inconsistent solution. In this paper, we propose a characterization of the consistency property using newly defined transitivity property for intuitionistic fuzzy multiplicative preference relations (IFMPR) together with complementing missing elements for incomplete IFMPR. In 2015 Jiang et al. worked on incomplete intuitionistic fuzzy multiplicative preference relations (incomplete IFMPRs) in which the IFMPRs split into two multiplicative preference relation (MPRs), and the missing elements were calculated by using the consistency of MPRs. Using new transitivity property of IFMPR, and we have developed two different methods to find the missing element of IFMPRs. The first method is two-step procedure method containing estimating step followed by adjusting step. In estimating step, the missing elements of incomplete IFMPRs are calculated by using a new transitive property instead of splitting IFMPRs into two multiplicative preference relations(MPRs). Sometimes the initial value may not satisfy the conditions of IFMPRs. An optimization model is developed in the second step to adjust the initial values that are solved by MATLAB optimization tool. The second proposed method is goal programming model based on new transitivity property to calculate the missing elements directly. Acceptably Consistent with complete IFMPRs is also checked. Two numerical examples are carried out to illustrate the above-said methods.

A robust method for the development of mechanically, thermally stable anti-reflective and self-cleaning coatings through in-situ formation of hierarchical raspberry-like mesoporous nanoparticles

Mamata Pradhan 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.105 No.-

A robust formulation was developed to produce anti-reflective and self-cleaning coatings, consisting ofhierarchical mesoporous silica, modified mesoporous titania nanoparticles and siloxane resin along withother ingredients. The hierarchical arrangement of nanoparticles by the process of self-assembly alongwith the polymerization of resin developed hierarchical micro and nanoscale structure on the coated surfacebecause of the in-situ generation of raspberry-like particles during film formation. A systematicstudy was carried out to investigate the effect of additives on the microstructure, optical property andwettability of the coatings. The optimum composition of the coating has anti-reflective property withmaximum transmittance of 99.6% (364 nm) with an absolute increase in transmittance of 5.3% in thewavelength range of 360–600 nm with a contact angle of 140 with water. The addition ofHexamethyldisilazane (HMDS) into the formulation enhanced the hydrophobicity of the coatings byextending the formation of more micro-nano scale structure. Moreover, developed coatings have 5Badhesion, significant humidity resistance, passed the 3H pencil hardness test and are thermally stableup to 250 C. The developed process is also suitable for low temperature organic substrates, feasiblefor scale-up production and the stable formulation can be available in a two-pack system.

Time Slot Exchange Protocol in a Reservation Based MAC for MANET

Mamata Koirala,Qi Ji,Jaeho Choi 한국융합신호처리학회 2009 융합신호처리학회 논문지 (JISPS) Vol.10 No.3

Recently, much attention to a self-organizing mobile ad-hoc network is escalating along with progressive deployment of wireless networks in our everyday life. Being readily deployable, the MANET (mobile ad hoc network) can find its applications to emergency medical service, customized calling service, group-based communications, and military purposes. In this paper we investigate a time slot exchange problem found in the time slot based MAC, that is designed for IEEE 802.11b interfaces composing a MANET. The paper provides a method to maintain the quality of voice call by providing a new time slot when the channel assigned for that time slot gets noisy with interferences induced from other nodes, which belong to the same and/or other subgroups. In order to assess the performance of the proposed algorithm, a set of simulations using the OPNET modeler has been performed assuming that the IEEE 802.11b interfaces are operating under a modified MAC, which is a time slot based reservation MAC implemented in the PCF part of the superframe. In a real-time voice call service over a MANET of a size 500 x 500 meter squares with the number of nodes up to 100, the simulation results are collected and analyzed with respect to the packet loss rate and packet delay. The results show us that the proposed time slot exchange protocol improves the quality of voice call over that of plain DCF.

Intraoral HIV-associated Burkitt’s lymphoma: a rare case report with special emphasis on differential diagnosis

Mamata Kamat,Uma Datar,Sampada Kanitkar,Sanjay Byakodi 대한구강악안면외과학회 2019 대한구강악안면외과학회지 Vol.45 No.4

Individuals with human immunodeficiency virus (HIV) infection present with unique intraoral manifestations of various neoplasms. Intraoral HIV-associated Burkitt’s lymphoma is a rare presentation, especially in patients of Indian origin and may present as an initial sign of HIV. The objective of this paper is to report a rare case of Burkitt’s lymphoma in an HIV-positive Indian patient along with a special emphasis on differential diagnosis. A 30-year-old Indian female presented with a solitary, well-defined, exophytic mass extending anteroposteriorly and buccolingually from the 35th to 38th regions with no evidence of intraosseous extension. An incisional biopsy was performed, and histopathology showed sheets of neoplastic lymphoid cells with numerous tingible body macrophages with clear cytoplasm, presenting a starry sky appearance, suggesting a diagnosis of BL. The tumor cells were positive for CD10, CD20, c-myc, and Epstein-Barr virus, with a nearly 100% Ki-67 proliferative index. The patient tested positive for HIV. This report indicates the importance of immunohistochemical analysis to differentiate Burkitt’s lymphoma from other similar lesions like diffuse large B-cell lymphoma. Thorough knowledge of the clinical presentation, etiopathogenesis, histopathology, and immunoprofile of intraoral HIV-associated Burkitt’s lymphoma is essential among clinicians and pathologists.

Low temperature processing of Li-Mn-Ti ferrite ceramics with V2O5 addition and effects on microstructural and B-H loop properties.

Mamata Maisnam 한양대학교 세라믹연구소 2017 Journal of Ceramic Processing Research Vol.18 No.5

Lithium manganese titanium ferrites were prepared by adding different amount of V2O5 by the ceramic technique. Thecompounds have the compositional formula Li+0.6Mn4+0.1Ti4+0.1Fe3+2.20O2-4 +(x) V2O5 where x= 0.0, 0.1, 0.2 and 0.3 wt. % is theamount of V2O5 added. The samples were pre-sintered at 650 oC for 2 h and then finally sintered at 950 oC for 1 h. XRD studiesconfirmed all the samples with single phase spinel structures. Various structural parameters were obtained from the XRDdata. SEM micrographs revealed the microstructures of the prepared samples. Curie temperature decreased with increase ofV2O5 addition. B-H loops were traced from the sintered torroidal samples. Various hysteresis parameters like remanance,coercivity, remanance ratio etc for varied V2O5 additions were determined from the loop. These properties were comparedwith those measured from sample of same composition but prepared with 0.5 wt% of Bi2O3 addition and sintered at 1050 oCfor 4 h.The results of the measurements are discussed in the paper.

Time Slot Exchange Protocol in a Reservation Based MAC for MANET

Koirala, Mamata,Ji, Qi,Choi, Jae-Ho The Korea Institute of Convergence Signal Processi 2009 융합신호처리학회 논문지 (JISPS) Vol.10 No.3

Recently, much attention to a self-organizing mobile ad-hoc network is escalating along with progressive deployment of wireless networks in our everyday life. Being readily deployable, the MANET (mobile ad hoc network) can find its applications to emergency medical service, customized calling service, group-based communications, and military purposes. In this paper we investigate a time slot exchange problem found in the time slot based MAC, that is designed for IEEE 802.11b interfaces composing a MANET. The paper provides a method to maintain the quality of voice call by providing a new time slot when the channel assigned for that time slot gets noisy with interferences induced from other nodes, which belong to the same and/or other subgroups. In order to assess the performance of the proposed algorithm, a set of simulations using the OPNET modeler has been performed assuming that the IEEE 802.11b interfaces are operating under a modified MAC, which is a time slot based reservation MAC implemented in the PCF part of the superframe. In a real-time voice call service over a MANET of a size 500 ${\times}$ 500 meter squares with the number of nodes up to 100, the simulation results are collected and analyzed with respect to the packet loss rate and packet delay. The results show us that the proposed time slot exchange protocol improves the quality of voice call over that of plain DCF.

Molecular Basis of Resistance to Selected Antimicrobial Agents in the Emerging Zoonotic Pathogen <i>Streptococcus suis</i>

Gurung, Mamata,Tamang, Migma Dorji,Moon, Dong Chan,Kim, Su-Ran,Jeong, Jin-Ha,Jang, Geum-Chan,Jung, Suk-Chan,Park, Yong-Ho,Lim, Suk-Kyung American Society for Microbiology 2015 Journal of clinical microbiology Vol.53 No.7

<P>Characterization of 227 <I>Streptococcus suis</I> strains isolated from pigs during 2010 to 2013 showed high levels of resistance to clindamycin (95.6%), tilmicosin (94.7%), tylosin (93.8%), oxytetracycline (89.4%), chlortetracycline (86.8%), tiamulin (72.7%), neomycin (70.0%), enrofloxacin (56.4%), penicillin (56.4%), ceftiofur (55.9%), and gentamicin (55.1%). Resistance to tetracyclines, macrolides, aminoglycosides, and fluoroquinolone was attributed to the <I>tet</I> gene, <I>erm</I>(B), <I>erm</I>(C), <I>mph</I>(C), and <I>mef</I>(A) and/or <I>mef</I>(E) genes, <I>aph(3′)-IIIa</I> and <I>aac(6′)-Ie-aph(2″)-Ia</I> genes, and single point mutations in the quinolone resistance-determining region of ParC and GyrA, respectively.</P>

Improved Extracellular Enzyme-mediated Production of 7,10-dihydroxy-8(E)-octadecenoic Acid by Pseudomonas aeruginosa

정지완,SINGHVI MAMATA SACHIN,김범수 한국생물공학회 2022 Biotechnology and Bioprocess Engineering Vol.27 No.3

In this study, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) was produced using extracellular enzymes present in the supernatant of Pseudomonas aeruginosa. DOD concentration and productivity were improved using extracellular enzymes obtained from P. aeruginosa culture broth than using conventional whole cell culture method. Among the different carbon sources used during cell preculture, glycerol showed higher DOD production than using glucose or crude glycerol. In batch process, the highest concentration of DOD (8.82 g/L) was accomplished using supernatant derived from 12 h-grown pre-culture of P. aeruginosa strain after 72 h of bioconversion process. To further improve DOD production, a fed-batch process was used with the addition of surfactant and enzyme concentrate. The fed-batch process using a 4-fold concentrated enzyme solution with Tween 80 yielded the highest DOD concentration (27.5 g/L at 72 h) with an 8.28-fold increase in DOD production compared to using whole cells. The prominence of this study was that the highest DOD production (27.5 g/L) ever reported was achieved using extracellular enzymes via a fed-batch process. Another significant aspect of this study is the possibility of utilizing abundantly available crude glycerol substrate for DOD production, which will help direct the development of sustainable process. Therefore, the overall study is projected to speed up the development of DOD production using inexpensive substrates such as crude glycerol on a larger scale.