Analysis of tribological behavior of Al/Gr/MoS2 surface composite fabricated by friction stir process

Gupta Manoj Kumar 한국탄소학회 2020 Carbon Letters Vol.30 No.4

The life span of many engineering components depends upon their surface properties. The improved surface properties of the materials are essential for enhancing the mechanical and tribological performance of the material. In many applications, the components required only improved surface properties without changing the entire volume properties of the material. The friction stir process (FSP) is a novel processing technique for the fabrication of such surface composites. In the present investigation, the surface composites were fabricated by incorporating molybdenum disulfde (MoS2) and graphite (Gr) as reinforcement on the surface of aluminum alloy (Al 1120) through the friction stir process (FSP) at tool rotational speed of 1400 rpm and tool feed rate of 40 mm/min process parameters using square profle FSP tool. The tribological behaviors of fabricated surface composites were calculated by using a pin on disk tribometer. It was observed that the wear resistance of surface composites improved as compared to the matrix material.

Flexible High-Performance Lead-Free Na_0.47K_0.47Li_0.06NbO₃ Microcube-Structure-Based Piezoelectric Energy Harvester

Gupta, Manoj Kumar,Kim, Sang-Woo,Kumar, Binay American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.3

<P>Lead-free piezoelectric nano- and microstructure-based generators have recently attracted much attention due to the continuous demand of self-powered body implantable devices. We report the fabrication of a high-performance flexible piezoelectric microgenerator based on lead-free inorganic piezoelectric Na0.47K0.47Li0.06NbO3 (NKLN) microcubes for the first time. The composite generator is fabricated using NKLN microcubes and polydimethylsiloxane (PDMS) polymer on a flexible substrate. The flexible device exhibits excellent performance with a large recordable piezoelectric output voltage of 48 V and output current density of 0.43 mu A/cm(2) under vertical compressive force of 2 kgf, for which an energy conversion efficiency of about 11% has been achieved. Piezoresponse and ferroelectric studies reveal that NKLN microcubes exhibited high piezoelectric charge coefficient (d(33)) as high as 460 pC/N and a well-defined hysteresis loops with remnant polarization and coercive field of 13.66 mu C/cm(2) and 19.45 kV/cm, respectively. The piezoelectric charge generation mechanism from NKLN microgenerator are discussed in the light of the high d33 and alignment of electric dipoles in polymer matrix and dielectric constant of NKLN microcubes. It has been demonstrated that the developed power generator has the potential to generate high electric output power under mechanical vibration for powering biomedical devices in the near future.</P>

Highly efficient flexible piezoelectric nanogenerator and femtosecond two-photon absorption properties of nonlinear lithium niobate nanowires

Gupta, Manoj Kumar,Aneesh, Janardhanakurup,Yadav, Rajesh,Adarsh, K. V.,Kim, Sang-Woo American Institute of Physics 2017 JOURNAL OF APPLIED PHYSICS - Vol.121 No.17

Running of high patient volume radiation oncology department during COVID-19 crisis in India: our institutional strategy

Manoj Gupta,Rachit Ahuja,Sweety Gupta,Deepa Joseph,Rajesh Pasricha,Swati Verma,Laxman Pandey 대한방사선종양학회 2020 Radiation Oncology Journal Vol.38 No.2

Purpose: Due to COVID 19 pandemic, the treatment of cancer patients has become a dilemma for every oncologist. Cancer patients are at an increased risk of immunosuppression and have a higher risk to acquire any infection. There are individual experiences from some centers regarding the management of cancer patients during such a crisis. So we have developed our institutional strategy to balance between COVID and cancer management. Materials and Methods: Radiation Oncology departmental meeting was held to prepare a consensus document on Radiotherapy schedules and department functioning during this pandemic. Results: Strategies were taken in form of following areas were steps need to be taken to decrease risk of infection, categorise treatment on the basis of priority, radiotherapy schedules modification, academic meetings and management of COVID positive patient/personnel in Radiation Oncology department. Conclusion: We hope to strike the balance in overcoming both the battles and emerge as winners. Stringent long term follow up will be done for assessing the response or any unforeseen treatment related sequelae.

Two-Dimensional Vanadium-Doped ZnO Nanosheet-Based Flexible Direct Current Nanogenerator

Gupta, Manoj Kumar,Lee, Ju-Hyuck,Lee, Keun Young,Kim, Sang-Woo American Chemical Society 2013 ACS NANO Vol.7 No.10

<P>Here, we report the synthesis of lead-free single-crystalline two-dimensional (2D) vanadium(V)-doped ZnO nanosheets (NSs) and their application for high-performance flexible direct current (DC) power piezoelectric nanogenerators (NGs). The vertically aligned ZnO nanorods (NRs) converted to NS networks by V doping. Piezoresponse force microscopy studies reveal that vertical V-doped ZnO NS exhibit typical ferroelectricity with clear phase loops, butterfly, and well-defined hysteresis loops with a piezoelectric charge coefficient of up to 4 pm/V, even in 2D nanostructures. From pristine ZnO NR-based NGs, alternating current (AC)-type output current was observed, while from V-doped ZnO NS-based NGs, a DC-type output current density of up to 1.0 μAcm<SUP>–2</SUP> was surprisingly obtained under the same vertical compressive force. The growth mechanism, ferroelectric behavior, charge inverted phenomena, and high piezoelectric output performance observed from the V-doped ZnO NS are discussed in terms of the formation of an ionic layer of [V(OH)<SUB>4</SUB><SUP>–</SUP>], permanent electric dipole, and the doping-induced resistive behavior of ZnO NS.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-10/nn403428m/production/images/medium/nn-2013-03428m_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn403428m'>ACS Electronic Supporting Info</A></P>

Evaluation of RECIST, PERCIST, EORTC, and MDA Criteria for Assessing Treatment Response with Ga68-PSMA PET-CT in Metastatic Prostate Cancer Patient with Biochemical Progression: a Comparative Study

Manoj Gupta,Partha Sarathi Choudhury,Sudhir Rawal,Harish Chandra Goel,S. Avinash Rao 대한핵의학회 2018 핵의학 분자영상 Vol.52 No.6

Purpose The aim of the study was to compare response evaluation criteria in solid tumours 1.1 (RECIST 1.1), positron emissiontomography response criteria in solid tumours (PERCIST), European organisation for research and treatment of cancer (EORTC),andMDAnderson (MDA) criteria for response assessment by Gallium 68-prostate-specific membrane antigen positron emissiontomography-computed tomography (Ga68-PSMA PET-CT) in metastatic adenocarcinoma prostate cancer (mPCa) patients withbiochemical progression. Methods Eighty-eight mPCa patients with pre and post treatment Ga68-PSMA PET-CTwere included. A ≥ 25% increase and ≥2 ng/ml above the nadir if prostate specific antigen (PSA) drop or ≥ 2 ng/ml above the baseline if PSA does not drop wasconsidered as biochemical progression. RECIST 1.1 and MDA criteria for morphology and PERCIST and EORTC criteria formolecular response were investigated. Percentages of progressive disease (PD), partial response (PR), and stable disease (SD)were calculated. Chi-square test was used for statistical significance. Results Proportion of PD, SD, and PR by RECIST 1.1 and MDA criteria were 44 (50.57%), 39 (44.83%), 4 (4.6%), and 33(39.76%), 48 (57.83%), 2 (2.41%) respectively. Proportion of PD, SD, and PR by PERCIST and EORTC criteria were 71(80.68%), 11 (12.50%), 6 (6.82%), and 74 (84.09%), 8 (9.09%), 6 (6.82%) respectively. Chi-square test showed statisticallysignificant (P < 0.05) higher proportion of progression detected by both molecular criteria as compare to both morphologicalcriteria. Conclusion We concluded that for Ga68-PSMA PET-CT response evaluation, molecular criteria performed better than morphologicalcriteria in mPCa patient with PSA progression.

Safety Profile and Therapeutic Efficacy of One Cycle of Lu177-PSMA in End-Stage Metastatic Castration-Resistant Prostate Cancer Patients with Low Performance Status

Manoj Gupta,Partha Sarathi Choudhury,Sudhir Rawal,G. Karthikeyan,Vineet Talwar,Kumar Deep Dutta,Amitabh Singh 대한핵의학회 2019 핵의학 분자영상 Vol.53 No.6

Purpose The aimof this study was to evaluate safety and therapeutic efficacy of lutetium 177 prostate-specific membrane antigen (Lu-177-PSMA) in metastatic castration-resistant prostate cancer (mCRPC) patients with low performance status. Methods Twenty-two patients already treated with anti-androgens and docetaxel were enrolled for one cycle of Lu-177-PSMA therapy. Haemoglobin, total leukocyte counts, platelets and serum creatinine for toxicity profile while prostate specific antigen (PSA), Eastern Cooperative Oncology Group (ECOG) performance status, visual analogue scale (VAS) and analgesic quantification scale (AQS) for therapeutic efficacy were recorded pre and 8 weeks post therapy.Wilcoxon signed-rank and ANOVA tests were used for statistical analysis. Results Partial response (PR), stable disease (SD) and progressive disease (PD) for PSAwere seen in 5 (22.7%), 13 (59.1%) and 4 (18.2%) patients respectively treated with mean 6.88 GBq dose of Lu-177-PSMA. 8/22 (36.4%) patients showed ≥ 30% drop in PSA. Grade 3 haemoglobin toxicity was seen in 5/22 (22.7%) patients. No patient developed grade 4 haemoglobin toxicity. No patients had grade 3 or 4 leukocytopenia or thrombocytopenia. Wilcoxon signed-rank test showed statistical significant (P < 0.05) difference in pre and post treatment ECOG, VAS, and AQS scores. The ANOVA test showed statistically significant difference in mean doses of Lu-177-PSMA used in three PSA response groups while difference was non-significant for other variables. Conclusion We concluded that Lu-177-PSMA therapy has adequate pain palliation in end-stage mCRPC patients with low performance status and it has a potential to become effective therapeutic option in properly selected patients.

Gene clustering and co-expression analysis for the identification of putative transcription factors associated with the genes of secondary metabolic pathways in Plantago ovata Forsk. and its wild allies

Gupta Suruchi,Singh Ravail,Paul Prosenjit,Kaul Sanjana,Lattoo Surrinder K.,Dhar Manoj K. 한국식물생명공학회 2024 Plant biotechnology reports Vol.18 No.1

Genus Plantago of Plantaginaceae family is bestowed with a repertoire of structurally diverse secondary metabolites that have not only been used as therapeutics but also effect the plant physiology by conferring adaptive advantages under stress. Assuming that domestication process in plants has influenced their secondary metabolites, we performed a comparative transcriptome of wild and cultivated species of Plantago to analyze the variation in the expression of genes related to sec- ondary metabolite pathways. GO and KEGG analysis of DEGs in wild species showed their enrichment in abiotic stresses, oxidation–reduction and secondary metabolite related pathways. Overall, we found upregulation of genes of carotenoid, flavonoid and phenylpropanoid, isoprenoid, terpenoid and alkaloid pathways in wild species of Plantago in particular, P. lanceolata while mucilage pathway-related genes showed higher expression in P. ovata. Moreover, transcriptome data pre- sented putative transcription factors associated with terpenoids, carotenoid and phenylpropanoid biosynthetic pathways which were also identified using co-expression analysis of cluster 9 (secondary metabolite enriched gene cluster). Taken together, the genomic resource obtained from the present study form a valuable repository of genetic information for elucidating and exploring the secondary metabolic circuitry of Plantagos. Further, information on the regulatory aspects of genes related to secondary metabolites, shall aid in the enhanced production of valuable metabolites in these plants.

An Energy Efficient Distributed Approach-Based Agent Migration Scheme for Data Aggregation in Wireless Sensor Networks

Gupta, Govind P.,Misra, Manoj,Garg, Kumkum Korea Information Processing Society 2015 Journal of information processing systems Vol.11 No.1

The use of mobile agents for collaborative processing in wireless sensor network has gained considerable attention. This is when mobile agents are used for data aggregation to exploit redundant and correlated data. The efficiency of agent-based data aggregation depends on the agent migration scheme. However, in general, most of the proposed schemes are centralized approach-based schemes where the sink node determines the migration paths for the agents before dispatching them in the sensor network. The main limitations with such schemes are that they need global network topology information for deriving the migration paths of the agents, which incurs additional communication overhead, since each node has a very limited communication range. In addition, a centralized approach does not provide fault tolerant and adaptive migration paths. In order to solve such problems, we have proposed a distributed approach-based scheme for determining the migration path of the agents where at each hop, the local information is used to decide the migration of the agents. In addition, we also propose a local repair mechanism for dealing with the faulty nodes. The simulation results show that the proposed scheme performs better than existing schemes in the presence of faulty nodes within the networks, and manages to report the aggregated data to the sink faster.

Assessment of the Antiulcer Potential of Moringa oleifera Root-Bark Extract in Rats

Manoj Kumar Choudhary,Surendra H. Bodakhe,Sanjay Kumar Gupta 사단법인약침학회 2013 Journal of Acupuncture & Meridian Studies Vol.6 No.4

In the present study, an ethanolic root-bark extract of Moringa oleifera (MO) was examined for its antiulcer potential in albino Wistar rats using two experimental models: ethanol-induced and pylorus ligation-induced gastric ulceration. The extract was orally administered at three different doses (150, 350, and 500 mg/kg) for 15 consecutive days. The antiulcer effects in rats treated with different doses of the extract and omeprazole (30 mg/kg, p.o.) were determined and compared statistically with the antiulcer effects in the control rats treated with saline (NaCl, 0.9%). The MO at doses of 350 and 500 mg/kg decreased the ulcer index significantly as compared to the control group (p < 0.01). The percentage protections against gastric ulcers were 82.58%, 85.13%, and 86.15% for MO doses of 150, 350, and 500 mg/kg, respectively, in the pylorus-ligated ulcer model and 55.75%, 59.33%, and 78.51%, respectively, in the ethanol-induced ulcer model. The MO significantly reduced the free acidity, total acidity, and ulcer index (p < 0.01) and increased the pH of gastric content compared with the control group. This study suggests that MO possesses valuable antiulcer, antisecretory, and cytoprotective activity. Thus, an ethanolic root-bark extract of Moringa oleifera can be used as source for an antiulcer drug.