Molecular Dynamics of Carbon Nanotubes Deposited on a Silicon Surface via Collision: Temperature Dependence

Saha, Leton C.,Mian, Shabeer A.,Kim, Hyo-Jeong,Saha, Joyanta K.,Matin, Mohammad A.,Jang, Joon-Kyung Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.2

We investigated how temperature influences the structural and energetic dynamics of carbon nanotubes (CNTs) undergoing a high-speed impact with a Si (110) surface. By performing molecular dynamics simulations in the temperature range of 100 - 300 K, we found that a low temperature CNT ends up with a higher vibrational energy after collision than a high temperature CNT. The vibrational temperature of CNT increases by increasing the surface temperature. Overall, the structural and energy relaxation of low temperature CNTs are faster than those of high temperature CNTs.

Replacement Value of Two Bangladeshi Varieties of Yellow Corn for Wheat in the Diet of Laying Chicken

Saha, P.K.,Chowdhury, S.D.,Das, S.C.,Saha, S.K. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.5

Two Bangladeshi varieties of yellow corn-'Barnali' and 'Khaibhutta' were chemically analysed and used in the diet of laying chicken to determine their replacement value for wheat. Both the new varieties of yellow corn were found to be good sources of energy and the CP contents were comparable to wheat. Forty two, 29-week old randomly selected Starcross Brown commercial pullets were assigned to 7 dietary treatments with 6 replicates, each being an experimental unit. Diets were formulated replacing wheat quantitatively by two varieties of yellow corn either 0, 50, 75 or 100 per cent from a wheat based control diet. The production performance of laying hens fed diets formulated with Barnali or Khaibhutta at different dietary levels during an experimental period of 16 weeks was satisfactory and comparable to wheat based diet. Except egg yolk colour, the other internal arid external egg quality characteristics at 8th and 16th weeks of the experiment did not differ significantly. The egg yolk colour improved significantly (p<0.01) by feeding both the new varieties of corn and the degree of pigmentation of yolk increased as the dietary levels of corn increased at the expense of wheat. Considering laying performance, the new varieties of yellow corn, Barnali or Khaibhutta can be used in layer diet as replacement of wheat. Such a replacement would better that wheat-based diet in terms of egg yolk pigmentation.

Antiinflammatory Evaluation of Leucas lavandulaefolia Rees. Extract

Saha, Kakali,Mukherjee, Pulok K.,Das, J.,Mandal, Subhash C.,Saha, B.P.,Pal, M. The Korean Society of Pharmacognosy 1996 Natural Product Sciences Vol.2 No.2

The antiinflammatory activity of the methanol extract of Leucas lavandulaefolia Rees was evaluated on different experimental models of inflammation in rats. The extract has been found to possess significant, inhibitory activity against carrageenin, histamine, serotonin, and dextran induced hind paw oedema in rats. The effect produced by extract was comparable to that of phenylbutazone and a prototype, nonsteroidal antiinflammatory agent.

Habitat complexity reduces prey vulnerability: An experimental analysis using aquatic insect predators and immature dipteran prey

Nabaneeta Saha,Goutam K. Saha,Gautam Aditya 한국응용곤충학회 2009 Journal of Asia-Pacific Entomology Vol.12 No.4

The effects of alternative prey and structural complexity of habitat on the selection of mosquito larvae by aquatic insect predators were evaluated in the laboratory. The water bugs Anisops bouvieri, Diplonychus (=Sphaerodema) rusticus, and D. annulatus, and the odonate nymphs, Ceriagrion coromandelianum and Brachydiplax chalybea chalybea, selected mosquito larvae based on their abundance relative to chironomid larvae and on the levels of habitat complexity. The effect of one prey species on the other was asymmetrical, as indicated through prey selectivity values. Compared to open habitat, the presence of macrophytes reduced the vulnerability of mosquito larvae while the effect was reverse in the presence of sediments. When both sediment and macrophytes were present in habitats, all the predators except D. annulatus consumed more mosquito larvae than chironomid larvae. The clearance rate, an indicator of predatory efficiency, varied among the predator species and habitat types. The results suggest that the outcome of the interactions between insect predators and mosquito immatures was context-dependent and that it was mediated by the presence of alternative controphic species and the habitat complexity. The effects of alternative prey and structural complexity of habitat on the selection of mosquito larvae by aquatic insect predators were evaluated in the laboratory. The water bugs Anisops bouvieri, Diplonychus (=Sphaerodema) rusticus, and D. annulatus, and the odonate nymphs, Ceriagrion coromandelianum and Brachydiplax chalybea chalybea, selected mosquito larvae based on their abundance relative to chironomid larvae and on the levels of habitat complexity. The effect of one prey species on the other was asymmetrical, as indicated through prey selectivity values. Compared to open habitat, the presence of macrophytes reduced the vulnerability of mosquito larvae while the effect was reverse in the presence of sediments. When both sediment and macrophytes were present in habitats, all the predators except D. annulatus consumed more mosquito larvae than chironomid larvae. The clearance rate, an indicator of predatory efficiency, varied among the predator species and habitat types. The results suggest that the outcome of the interactions between insect predators and mosquito immatures was context-dependent and that it was mediated by the presence of alternative controphic species and the habitat complexity.

Molecular Dynamics of Carbon Nanotubes Deposited on a Silicon Surface via Collision: Temperature Dependence

Leton C. Saha,Shabeer A. Mian,김효정,Mohammad A. Matin,Joyanta K. Saha,장준경 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.2

We investigated how temperature influences the structural and energetic dynamics of carbon nanotubes (CNTs) undergoing a high-speed impact with a Si (110) surface. By performing molecular dynamics simulations in the temperature range of 100 - 300 K, we found that a low temperature CNT ends up with a higher vibrational energy after collision than a high temperature CNT. The vibrational temperature of CNT increases by increasing the surface temperature. Overall, the structural and energy relaxation of low temperature CNTs are faster than those of high temperature CNTs.

Prognostic role of EGR1 in breast cancer: a systematic review

( Subbroto Kumar Saha ),( S. M. Riazul Islam ),( Tripti Saha ),( Afsana Nishat ),( Polash Kumar Biswas ),( Minchan Gil ),( Lewis Nkenyereye ),( Shaker El-sappagh ),( Saiful Islam ),( Ssang-goo Cho ) 생화학분자생물학회 2021 BMB Reports Vol.54 No.10

EGR1 (early growth response 1) is dysregulated in many cancers and exhibits both tumor suppressor and promoter activities, making it an appealing target for cancer therapy. Here, we used a systematic multi-omics analysis to review the expression of EGR1 and its role in regulating clinical outcomes in breast cancer (BC). EGR1 expression, its promoter methylation, and protein expression pattern were assessed using various publicly available tools. COSMIC-based somatic mutations and cBioPortal-based copy number alterations were analyzed, and the prognostic roles of EGR1 in BC were determined using Prognoscan and Kaplan-Meier Plotter. We also used bc-GenEx-Miner to investigate the EGR1 co-expression profile. EGR1 was more often downregulated in BC tissues than in normal breast tissue, and its knockdown was positively correlated with poor survival. Low EGR1 expression levels were also associated with increased risk of ER+, PR+, and HER2- BCs. High positive correlations were observed among EGR1, DUSP1, FOS, FOSB, CYR61, and JUN mRNA expression in BC tissue. This systematic review suggested that EGR1 expression may serve as a prognostic marker for BC patients and that clinicopathological parameters influence its prognostic utility. In addition to EGR1, DUSP1, FOS, FOSB, CYR61, and JUN can jointly be considered prognostic indicators for BC. [BMB Reports 2021; 54(10): 497-504]

Micellar Catalysis on 1,10-Phenanthroline Promoted Chromic Acid Oxidation of Ethane-1,2-diol in Aqueous Media at Room Temperature

Ghosh, Sumanta K.,Saha, Rumpa,Ghosh, Aniruddha,Basu, Ankita,Mukherjee, Kakali,Saha, Indrajit,Saha, Bidyut Korean Chemical Society 2012 대한화학회지 Vol.56 No.6

Under pseudo-first order conditions, the monomeric species of Cr(VI) was found to be kinetically active in the absence of phenanthroline (phen) whereas in the phen-promoted path, the Cr(VI)-phen complex undergoes a nucleophilic attack by etane-1,2-diol to form a ternary complex which subsequently experience a redox decomposition leading to hydroxy ethanal and Cr(III)-phen complex. The effect of the cationic surfactant (CPC), anionic surfactant (SDS) and neutral surfactant (TX-100) on the unpromoted and phen-promoted path have been studied. Micellar effects have been explained by considering the preferential partitioning of reactants between the micellar and aqueous phase. Combination of TX-100 and phenanthroline will be the ideal for chromic acid oxidation of ethane-1,2-diol in aqueous media.

An insight on land use and land cover change due to tourism growth in coastal area and its environmental consequences from West Bengal, India

Saha Jayanta,Paul Suman 대한공간정보학회 2021 Spatial Information Research Vol.29 No.4

In developing countries, tourism often considered as the tool of economic development. The coastal virgin environment provides lot of opportunities for establishment of tourism industries. Along the coastal tract of Purba Medinipur district of West Bengal, India, a number of tourism destinations have been emerged and. Mandarmani–Tajpur area has found as a booming of tourists during last 10–15 years. This study analyse the tourism-led land use change around these destinations during 2009 to 2019 and its environmental consequences. Google Earth satellite images of the study area for 2009 and 2019 have been utilized for LULC classification. Based on the data derived from LULC classification a land use change matrix has been constructed to identify the land use land cover change between 2009 and 2019. The result confirmed that decreased in agriculture land, vegetation cover, aquaculture with water bodies and sand dune. On the other part, current fallow, settlement area and area under tourism related activities have been found in increasing nature. The agriculture lands, current fallow, sand dunes, vegetation cover have been transformed into tourism area because of establishment of hotels and resorts and tourism related enterprises over the dunes, agriculture land current fallows. Hotels and resorts have been constructed by clearing of vegetation cover. Due to flourish of tourism activities within CRZ (Coastal Regulation Zone), entire landscape has been fragmented, vegetation cover degenerated, and dune ecology has been destructed. Finally, discussion has indicated to a sustainable tourism development plan for controlling the negative environmental consequences.

Valproic Acid Induces Endocytosis-Mediated Doxorubicin Internalization and Shows Synergistic Cytotoxic Effects in Hepatocellular Carcinoma Cells

Saha, Subbroto Kumar,Yin, Yingfu,Kim, Kyeongseok,Yang, Gwang-Mo,Abdal Dayem, Ahmed,Choi, Hye Yeon,Cho, Ssang-Goo MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.5

<P>Valproic acid (VPA), a well-known histone deacetylase (HDAC) inhibitor, is used as an anti-cancer drug for various cancers, but the synergistic anti-cancer effect of VPA and doxorubicin (DOX) combination treatment and its potential underlying mechanism in hepatocellular carcinoma (HCC) remain to be elucidated. Here, we evaluate the mono- and combination-therapy effects of VPA and DOX in HCC and identify a specific and efficient, synergistic anti-proliferative effect of the VPA and DOX combination in HCC cells, especially HepG2 cells; this effect was not apparent in MIHA cells, a normal hepatocyte cell line. The calculation of the coefficient of drug interaction confirmed the significant synergistic effect of the combination treatment. Concurrently, the synergistic apoptotic cell death caused by the VPA and DOX combination treatment was confirmed by Hoechst nuclear staining and Western blot analysis of caspase-3 and poly (ADP-ribose) polymerase (PARP) activation. Co-treatment with VPA and DOX enhanced reactive oxygen species (ROS) generation and autophagy, which were clearly attenuated by ROS and autophagy inhibitors, respectively. Furthermore, as an indication of the mechanism underlying the synergistic effect, we observed that DOX internalization, which was induced in the VPA and DOX combination-treated group, occurred via by the caveolae-mediated endocytosis pathway. Taken together, our study uncovered the potential effect of the VPA and DOX combination treatment with regard to cell death, including induction of cellular ROS, autophagy, and the caveolae-mediated endocytosis pathway. Therefore, these results present novel implications in drug delivery research for the treatment of HCC.</P>

Self-organized honeycomb-like nanoporous oxide layer for corrosion protection of type 304 stainless steel in an artificial seawater medium

Saha, Sourav Kr.,Park, Yang Jeong,Kim, Jung Woo,Cho, Sung Oh Elsevier 2019 Journal of molecular liquids Vol.296 No.-

<P><B>Abstract</B></P> <P>A new passivation technology for growing a self-organized nanoporous oxide layer with a honeycomb morphology on Type 304 stainless steel is proposed. FESEM, cross-sectional EDX and XRD are employed to evaluate the morphology, composition and crystal structure of the developed anodic film. Cross-sectional EDX analysis reveals that the nanoporous oxide layer contains a significant amount of fluoride species, which becomes negligible after successive annealing in air at 773 K for 2 h. XRD indicates that the amorphous nanoporous oxide layer is converted to a crystalline magnetite phase (Fe<SUB>3</SUB>O<SUB>4</SUB>) after annealing. Electrochemical analysis such as potentiodynamic polarization and electrochemical impedance spectroscopy reveals stainless steel with a thermally treated nanoporous oxide layer has improved corrosion resistance in an artificial seawater medium. FESEM analyses are employed to evaluate the stability and microscopic changes in the morphologies of the nanoporous oxide layer after prolonged immersion in the artificial seawater medium. The key factors and corrosion inhibition mechanism by the nanoporous oxide layer are also discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Self-organized nanoporous oxide layer has been developed by one step anodization. </LI> <LI> XRD reveals crystalline magnetite phase (Fe<SUB>3</SUB>O<SUB>4</SUB>) dominant after successive annealing. </LI> <LI> Stable and compact thermal oxide has formed beneath the nanoporous oxide layer. </LI> <LI> Thermally treated nanoporous oxide layer reduces corrosion rate of stainless steel. </LI> <LI> Oxide layer hindered the penetration of corrosive ions towards metal surface atoms. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>