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RICCI ρ-SOLITON IN A PERFECT FLUID SPACETIME WITH A GRADIENT VECTOR FIELD

  • Dibakar Dey;Pradip Majhi
    • Communications of the Korean Mathematical Society
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    • v.38 no.1
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    • pp.235-242
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    • 2023
  • In this paper, we studied several geometrical aspects of a perfect fluid spacetime admitting a Ricci ρ-soliton and an η-Ricci ρ-soliton. Beside this, we consider the velocity vector of the perfect fluid space time as a gradient vector and obtain some Poisson equations satisfied by the potential function of the gradient solitons.

Almost Kenmotsu Metrics with Quasi Yamabe Soliton

  • Pradip Majhi;Dibakar Dey
    • Kyungpook Mathematical Journal
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    • v.63 no.1
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    • pp.97-104
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    • 2023
  • In the present paper, we characterize, for a class of almost Kenmotsu manifolds, those that admit quasi Yamabe solitons. We show that if a (k, 𝜇)'-almost Kenmotsu manifold admits a quasi Yamabe soliton (g, V, 𝜆, 𝛼) where V is pointwise collinear with 𝜉, then (1) V is a constant multiple of 𝜉, (2) V is a strict infinitesimal contact transformation, and (3) (£Vh')X = 0 holds for any vector field X. We present an illustrative example to support the result.

Deuterium oxide stabilizes conformation of tubulin: a biophysical and biochemical study

  • Das, Amlan;Sinha, Sharmistha;Acharya, Bipul R;Paul, Pinaki;Bhattacharyya, Bhabatarak;Chakrabarti, Gopal
    • BMB Reports
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    • v.41 no.1
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    • pp.62-67
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    • 2008
  • The present study was aimed to elucidate the mechanism of stabilization of tubulin by deuterium oxide ($D_2O$). Rate of decrease of tryptophan fluorescence during aging of tubulin at 4$^{\circ}C$ and 37$^{\circ}C$ was significantly lower in $D_2O$ than in $H_2O$. Circular dichroism spectra of tubulin after incubation at 4$^{\circ}C$, suggested that complete stabilization of the secondary structure in D2O during the first 24 hours of incubation. The number of available cysteine measured by DTNB reaction was decreased to a lesser extent in $D_2O$ than in $H_2O$. . During the increase in temperature of tubulin, the rate of decrease of fluorescence at 335 nm and change of CD value at 222 nm was lesser in $D_2O$. Differential Scanning calorimetric experiments showed that the $T_m$ values for tubulin unfolding in $D_2O$ were 58.6$^{\circ}C$ and 62.17$^{\circ}C$, and in $H_2O$. those values were 55.4$^{\circ}C$ and 59.35$^{\circ}C$.

Effects of Rapid Thermal Annealing Temperature on Performances of Nanoscale FinFETs

  • Sengupta, M.;Chattopadhyay, S.;Maiti, C.K.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.9 no.4
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    • pp.266-272
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    • 2009
  • In the present work three dimensional process and device simulations were employed to study the performance variations with RTA. It is observed that with the increase in RTA temperature, the arsenic dopants from the source /drain region diffuse laterally under the spacer region and simultaneously acceptors (Boron) are redistributed from the central axis region of the fin towards the Si/SiO2 interface. As a consequence both drive current and peak cut-off frequency of an n-FinFET are observed to improve with RTA temperatures. Volume inversion and hence the flow of carries through the central axis region of the fin due to reduced scattering was found behind the performance improvements with increasing RTA temperature.

TEMPORAL AND SPATIO-TEMPORAL DYNAMICS OF A MATHEMATICAL MODEL OF HARMFUL ALGAL INTERACTION

  • Mukhopadhyay, B.;Bhattacharyya, R.
    • Journal of applied mathematics & informatics
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    • v.27 no.1_2
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    • pp.385-400
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    • 2009
  • The adverse effect of harmful plankton on the marine ecosystem is a topic of deep concern. To investigate the role of such phytoplankton, a mathematical model containing distinct dynamical equations for toxic and non-toxic phytoplankton is analyzed. Stability analysis of the resulting three equation model is carried out. A continuous time variation in toxin liberation process is incorporated into the model and a stability analysis of the resulting delay model is performed. The distributed delay model is then extended to include the spatial distribution of plankton and the delay-diffusion model is analyzed with spatial and spatiotemporal kernels. Conditions for diffusion-driven instability in both the cases are derived and compared to explore the significance of these kernels. Numerical studies are performed to justify analytical findings.

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Some Enzymes of Tricarboxylic Acid Cycle and Metabolites of Carbohydrate Metabolism in Adult Isoparorchis hypselobagri(Digenea: Trematoda) During in vitro Starvation

  • Bera, Bireshwar;Manna, Buddhadeb
    • International Journal of Industrial Entomology and Biomaterials
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    • v.18 no.2
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    • pp.91-95
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    • 2009
  • The presence of considerable amount of enzymes of TCA cycle isocitrate dehydrogenase (ICDH-NADP+, EC1.1.1.42), $\alpha$-ketogluterate dehydrogenase ($\alpha$-KGD, EC1.2.4.2) and malate dehydrogenase (MDH, EC1.1.1.37) in fresh control and in vitro starved adult Isoparorchis hypselobagri establish the functional TCA cycle in this fluke. The major metabolic end products are pyruvate, lactate, oxaloacetate and malate. The ratio of oxaloacetate/malate assess that oxaloacetate is reduced to malate and in this fluke the reverse TCA cycle is active. The pyruvate/lactate ratio shows pyruvate is reduced to lactate and the fluke is homolactate farmenters.

PSEUDO PROJECTIVE RICCI SYMMETRIC SPACETIMES

  • De, Uday Chand;Majhi, Pradip;Mallick, Sahanous
    • Communications of the Korean Mathematical Society
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    • v.33 no.2
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    • pp.571-580
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    • 2018
  • The object of the present paper is to prove the non-existence of pseudo projective Ricci symmetric spacetimes $(PW\;RS)_4$ with different types of energy momentum tensor. We also discuss whether a fluid $(PW\;RS)_4$ spacetime with the basic vector field as the velocity vector field of the fluid can admit heat flux. Next we consider perfect fluid and dust fluid $(PW\;RS)_4$ spacetimes respectively. Finally we construct an example of a $(PW\;RS)_4$ spacetime.

Biological Response Modifiers Influence Structure Function Relationship of Hematopoietic Stem and Stromal Cells in a Mouse Model of Leukemia

  • Basu, Kaustuv;Mukherjee, Joydeep;Law, Sujata;Chaudhuri, Samaresh
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2935-2941
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    • 2012
  • Biological response modifiers (BRMs) can alter interactions between the immune system and cancer cells to boost, direct, or restore the body's ability to fight disease. Mice with ethylnitrosourea- (ENU) induced leukemia were here used to monitor the therapeutic efficacy of lipopolysaccaride (LPS), Bacillus Calmette Guerin (BCG) and sheep erythrocytes (SRBC). Flow cytometry based CD34+ positivity analysis, clonogenicity, proliferation and ultrastructure studies using scanning electron microscopy (SEM) of stem cells in ENU induced animals with and without BRMs treatment were performed. BRMs improved the stem-stromal relationship structurally and functionally and might have potential for use as an adjunct in human stem cell therapy.