53 research outputs found
A Survey of Cellular Automata: Types, Dynamics, Non-uniformity and Applications
Cellular automata (CAs) are dynamical systems which exhibit complex global
behavior from simple local interaction and computation. Since the inception of
cellular automaton (CA) by von Neumann in 1950s, it has attracted the attention
of several researchers over various backgrounds and fields for modelling
different physical, natural as well as real-life phenomena. Classically, CAs
are uniform. However, non-uniformity has also been introduced in update
pattern, lattice structure, neighborhood dependency and local rule. In this
survey, we tour to the various types of CAs introduced till date, the different
characterization tools, the global behaviors of CAs, like universality,
reversibility, dynamics etc. Special attention is given to non-uniformity in
CAs and especially to non-uniform elementary CAs, which have been very useful
in solving several real-life problems.Comment: 43 pages; Under review in Natural Computin
Spectral analysis of molecular resonances in erbium isotopes: Are they close to semi-Poisson?
We perform a thorough analysis of the spectral statistics of experimental
molecular resonances, of bosonic erbium Er and Er isotopes,
produced as a function of magnetic field() by Frisch et al. [Nature 507,
(2014) 475], utilizing some recently derived surmises which interpolate between
Poisson and GOE and without unfolding. Supplementing this with an analysis
using unfolded spectrum, it is shown that the resonances are close to
semi-Poisson distribution. There is an earlier claim of missing resonances by
Molina et al. [Phys. Rev. E 92, (2015) 042906]. These two interpretations can
be tested by more precise measurements in future experiments.Comment: 7 pages, 6 figure
Energy level statistics of interacting trapped bosons
It is an well established fact that statistical properties of energy level
spectra are the most efficient tool to characterize nonintegrable quantum
systems. The study of statistical properties and spectral fluctuation in the
interacting many boson systems have developed a new interest in this direction.
Specially we are interested in the weakly interacting trapped bosons in the
context of Bose-Einstein condensation (BEC) as the energy spectrum shows a
transition from the collective to single particle nature with the increase in
the number of levels. However this has received less attention as it is
believed that the system may exhibit Poisson like fluctuations due to the
existence of external harmonic trap. Here we compute numerically the energy
levels of the zero-temperature many-boson systems which are weakly interacting
through the van der Waals potential and are in the 3D confined harmonic
potential. We study the nearest neighbour spacing distribution and the spectral
rigidity by unfolding the spectrum. It is found that increase in number of
energy levels for repulsive BEC induces a transition from a Wigner like form
displaying level repulsion to Poisson distribution for P(s). It does not follow
the GOE prediction. For repulsive interaction, the lower levels are correlated
and manifest level repulsion. For intermediate levels P (s) shows mixed
statistic which clearly signifies the existence of two energy scales: external
trap and interatomic interaction. Whereas for very high levels the trapping
potential dominates, genarating Poisson distribution. Comparison with
mean-field results for lower levels are also presented. For attractive BEC near
the critical point we observe the Shrielman like peak near s=0 which signifies
the presence of large number of quasi-degenerate states.Comment: 12 page
Sustainable Generation of Ni(OH)2 Nanoparticles for the Green Synthesis of 5-Substituted 1 H-Tetrazoles:A Competent Turn on Fluorescence Sensing of H2O2
A mutually correlated green protocol has been devised that originates from a sustainable production of β-Ni(OH)2 nanoparticles which is used for an efficient catalytic synthesis of versatile substituted tetrazoles, under mild reaction conditions in water via a simple, one-pot, eco-friendly method. The synthesis is followed by derivatization into a highly fluorescence active compound 9-(4-(5-(quinolin-2-yl)-1H-tetrazol-1-yl)phenyl)-9H-carbazole that can be used at tracer concentrations (0.1 μM) to detect as well as quantify hydrogen peroxide down to 2 μM concentration. The nanocatalyst was synthesized by a simple, proficient, and cost-effective methodology and characterized thoroughly by UV-vis absorption and Fourier transform infrared spectra, N2 adsorption/desorption, high resolution transmission electron microscopy, powder X-ray diffraction pattern, field emission scanning electron microscopy, and thermogravimetric analysis. Broad substrate scope, easy handling, higher efficiency, low cost, and reusability of the catalyst are some of the important features of this heterogeneous catalytic system. The strong analytical performance of the resultant derivative in low-level quantification of potentially hazardous hydrogen peroxide is the key success of the overall green synthesis procedure reported here
Spectral fluctuation and noise in the energy level statistics of interacting trapped bosons
It has been recently shown numerically that the transition from integrability
to chaos in quantum systems and the corresponding spectral fluctuations are
characterized by noise with . The
system of interacting trapped bosons is inhomogeneous and a complex system. The
presence of external harmonic trap makes it more interesting as in the atomic
trap the bosons occupy partly degenerate single-particle states. Earlier
theoretical and experimental results show that at zero temperature the
low-lying levels are of collective nature and high-lying excitations are of
single particle nature. We observe that for few bosons, distribution
shows the Shnirelman peak which exhibits a large number of quasi-degenerate
states. For large number of bosons the low-lying levels are strongly affected
by the interatomic interaction and the corresponding level fluctuation shows a
transition to Wigner with increase in particle number. It does not follow GOE
(Gaussian Orthogonal Ensemble) Random Matrix predictions. For high-lying levels
we observe the uncorrelated Poisson distribution. Thus it may be a very
realistic system to prove that noise is ubiquitous in
nature
High monocytic MDSC signature predicts multi-drug resistance and cancer relapse in non-Hodgkin lymphoma patients treated with R-CHOP
IntroductionNon-Hodgkin Lymphoma (NHL) is a heterogeneous lymphoproliferative malignancy with B cell origin. Combinatorial treatment of rituximab, cyclophsphamide, hydroxydaunorubicin, oncovin, prednisone (R-CHOP) is the standard treatment regimen for NHL, yielding a complete remission (CR) rate of 40-50%. Unfortunately, considerable patients undergo relapse after CR or initial treatment, resulting in poor clinical implications. Patient’s response to chemotherapy varies widely from static disease to cancer recurrence and later is primarily associated with the development of multi-drug resistance (MDR). The immunosuppressive cells within the tumor microenvironment (TME) have become a crucial target for improving the therapy efficacy. However, a better understanding of their involvement is needed for distinctive response of NHL patients after receiving chemotherapy to design more effective front-line treatment algorithms based on reliable predictive biomarkers.MethodsPeripheral blood from 61 CD20+ NHL patients before and after chemotherapy was utilized for immunophenotyping by flow-cytometry at different phases of treatment. In-vivo and in-vitro doxorubicin (Dox) resistance models were developed with murine Dalton’s lymphoma and Jurkat/Raji cell-lines respectively and impact of responsible immune cells on generation of drug resistance was studied by RT-PCR, flow-cytometry and colorimetric assays. Gene silencing, ChIP and western blot were performed to explore the involved signaling pathways.ResultsWe observed a strong positive correlation between elevated level of CD33+CD11b+CD14+CD15- monocytic MDSCs (M-MDSC) and MDR in NHL relapse cohorts. We executed the role of M-MDSCs in fostering drug resistance phenomenon in doxorubicin-resistant cancer cells in both in-vitro, in-vivo models. Moreover, in-vitro supplementation of MDSCs in murine and human lymphoma culture augments early expression of MDR phenotypes than culture without MDSCs, correlated well with in-vitro drug efflux and tumor progression. We found that MDSC secreted cytokines IL-6, IL-10, IL-1β are the dominant factors elevating MDR expression in cancer cells, neutralization of MDSC secreted IL-6, IL-10, IL-1β reversed the MDR trait. Moreover, we identified MDSC secreted IL-6/IL-10/IL-1β induced STAT1/STAT3/NF-κβ signaling axis as a targeted cascade to promote early drug resistance in cancer cells.ConclusionOur data suggests that screening patients for high titre of M-MDSCs might be considered as a new potential biomarker and treatment modality in overcoming chemo-resistance in NHL patients
Molecular characterization and clinical relevance of metabolic expression subtypes in human cancers.
Metabolic reprogramming provides critical information for clinical oncology. Using molecular data of 9,125 patient samples from The Cancer Genome Atlas, we identified tumor subtypes in 33 cancer types based on mRNA expression patterns of seven major metabolic processes and assessed their clinical relevance. Our metabolic expression subtypes correlated extensively with clinical outcome: subtypes with upregulated carbohydrate, nucleotide, and vitamin/cofactor metabolism most consistently correlated with worse prognosis, whereas subtypes with upregulated lipid metabolism showed the opposite. Metabolic subtypes correlated with diverse somatic drivers but exhibited effects convergent on cancer hallmark pathways and were modulated by highly recurrent master regulators across cancer types. As a proof-of-concept example, we demonstrated that knockdown of SNAI1 or RUNX1—master regulators of carbohydrate metabolic subtypes-modulates metabolic activity and drug sensitivity. Our study provides a system-level view of metabolic heterogeneity within and across cancer types and identifies pathway cross-talk, suggesting related prognostic, therapeutic, and predictive utility
Investigation on pH dependent uptake of Cr(III) and Cr(VI) by Baker’s yeast
417-419Yeast cells of Saccharomyces cerevisiae were found to accumulate ⁵¹Cr(III) radioisotope at basic pH in trace level. There was no uptake of Cr(VI) at the same pH (~10.5). An assay of the products of cell lysis reveals that Cr(III) first gets adsorbed at the cell wall and then slowly enters the cytoplasm. On the other hand Cr(VI) has a faster penetration into the cytoplasm which increases with time, attains a maximum value and then release the metal ion from cytoplasm. The behavior and uptake kinetics of ⁵¹Cr(III) or ⁵¹Cr(VI) were studied using -spectrometry
Separation of gold and silver using a chelating resin - Thiosemicarbazide incorporated Amberlite IRC-50
531-534A thiosemicarbazide group incorporated
into a weakly acidic resin, Amberlite IRC-50 can selectively entrap two noble
metals, gold and silver. The exchange capacity of the newly
formed resin for Au(III) and Ag(I) is
satisfactory. The resin can be utilized for the separation of these noble
metals from different complex matrices
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