854 research outputs found
Estimates and Higher-Order Spectral Shift Measures in Several Variables
In recent years, higher-order trace formulas of operator functions have
attracted considerable attention to a large part of the perturbation theory
community. In this direction, we prove estimates for traces of higher-order
derivatives of multivariable operator functions with associated scalar
functions arising from multivariable analytic function space and, as a
consequence, derive higher-order spectral shift measures for pairs of tuples of
commuting contractions under Hilbert-Schmidt perturbations. These results
substantially extend the main results of \cite{Sk15}, where the estimates were
proved for traces of first and second-order derivatives of multivariable
operator functions. In the context of the existence of higher-order spectral
shift measures, our results extend the relative results of \cite{DySk09,
PoSkSu14} from a single-variable to a multivariable setting under
Hilbert-Schmidt perturbations. Our results rely crucially on heavy uses of
explicit expressions of higher-order derivatives of operator functions and
estimates of the divided deference of multivariable analytic functions, which
are developed in this paper, along with the spectral theorem of tuples of
commuting normal operators.Comment: 20 page
Strength vs. Accessibility: unraveling the patterns of self-recognition in a conformationally locked amino alcohol
Unlike the self-assembly of aminols studied till date, that of the conformationally locked, trans-amino alcohol under study is unique in having the amino protons serving as mere spectators in the crystal packing. The principal non-covalent interactions, holding the molecules in the crystal lattice, are O-H···N hydrogen bonds, and the rarely encountered π-π stacking interactions between the isolated double bonds. Experimental charge density analyses have been carried out on the amino alcohol not only to characterize the non-covalent interactions existing in the supramolecular assembly in terms of the topological features of electron density at their bond critical points, but also to elucidate the apparent presence of the "spectator" amino hydrogen atoms beyond the criteria of mere geometry
Garcinol loaded vitamin E TPGS emulsified PLGA nanoparticles: preparation, physicochemical characterization, in vitro and in vivo studies
Garcinol (GAR) is a naturally occurring polyisoprenylated phenolic compound. It has been recently
investigated for its biological activities such as antioxidant, anti-inflammatory, anti ulcer, and
antiproliferative effect on a wide range of human cancer cell lines. Though the outcomes are very
promising, its extreme insolubility in water remains the main obstacle for its clinical application. Herein
we report the formulation of GAR entrapped PLGA nanoparticles by nanoprecipitation method using
vitamin E TPGS as an emulsifier. The nanoparticles were characterized for size, surface morphology,
surface charge, encapsulation efficiency and in vitro drug release kinetics. The MTT assay depicted a
high amount of cytotoxicity of GAR-NPs in B16F10, HepG2 and KB cells. A considerable amount of cell
apoptosis was observed in B16f10 and KB cell lines. In vivo cellular uptake of fluorescent NPs on B16F10
cells was also investigated. Finally the GAR loaded NPs were radiolabeled with technetium-99m with
>95% labeling efficiency and administered to B16F10 melanoma tumor bearing mice to investigate the
in vivo deposition at the tumor site by biodistribution and scintigraphic imaging study. In vitro cellular
uptake studies and biological evaluation confirm the efficacy of the formulation for cancer treatmen
Effect of shell thickness on exciton and biexciton binding energy of a ZnSe/ZnS core/shell quantum dot
The exciton and biexciton binding energy have been studied for a ZnSe/ZnS
core/shell quantum dot using WKB (Wentzel-Kramers-Brillouin) approximation. The
exciton binding energy increases for small shell thickness and for large
thickness, the binding energy again starts decreasing. A similar result is
obtained for biexcitons where for thicker shells, the biexciton attains
antibonding.Comment: 5 Figure
Development of a water-based cooling system for the Muon Chamber detector system of the CBM experiment
A water-based cooling system is being investigated to meet the cooling
requirement of the Gas Electron Multiplier (GEM) based Muon Chamber (MuCh)
detector system of the Compressed Baryonic Matter (CBM) experiment at GSI,
Germany. The system is based on circulating cold water through the channels
inside an aluminium plate. The aluminium plate is attached to a GEM chamber. A
feasibility study is conducted on one small and two real-size prototype cooling
plates. A microcontroller based unit has been built and integrated into the
system to achieve automatic control and monitoring of temperature on plate
surface. The real-size prototypes have been used in a test beam experiment at
the CERN SPS (Super Proton Synchrotron) with the lead beam on a lead target. A
setup using three prototype modules has been prepared in the lab for testing in
a simulated real life environment. This paper discusses the working principle,
mechanical design, fabrication, and test results of the cooling prototypes in
detail.Comment: 8 pages, 12 figures, 2 table
TLR4 is one of the receptors for Chikungunya virus envelope protein E2 and regulates virus induced pro-inflammatory responses in host macrophages
Toll like receptor 4 (TLR4), a pathogen-associated molecular pattern (PAMP) receptor, is known to exert inflammation in various cases of microbial infection, cancer and autoimmune disorders. However, any such involvement of TLR4 in Chikungunya virus (CHIKV) infection is yet to be explored. Accordingly, the role of TLR4 was investigated towards CHIKV infection and modulation of host immune responses in the current study using mice macrophage cell line RAW264.7, primary macrophage cells of different origins and in vivo mice model. The findings suggest that TLR4 inhibition using TAK-242 (a specific pharmacological inhibitor) reduces viral copy number as well as reduces the CHIKV-E2 protein level significantly using p38 and JNK-MAPK pathways. Moreover, this led to reduced expression of macrophage activation markers like CD14, CD86, MHC-II and pro-inflammatory cytokines (TNF, IL-6, MCP-1) significantly in both the mouse primary macrophages and RAW264.7 cell line, in vitro. Additionally, TAK-242-directed TLR4 inhibition demonstrated a significant reduction of percent E2-positive cells, viral titre and TNF expression in hPBMC-derived macrophages, in vitro. These observations were further validated in TLR4-knockout (KO) RAW cells. Furthermore, the interaction between CHIKV-E2 and TLR4 was demonstrated by immuno-precipitation studies, in vitro and supported by molecular docking analysis, in silico. TLR4-dependent viral entry was further validated by an anti-TLR4 antibody-mediated blocking experiment. It was noticed that TLR4 is necessary for the early events of viral infection, especially during the attachment and entry stages. Interestingly, it was also observed that TLR4 is not involved in the post-entry stages of CHIKV infection in host macrophages. The administration of TAK-242 decreased CHIKV infection significantly by reducing disease manifestations, improving survivability (around 75%) and reducing inflammation in mice model. Collectively, for the first time, this study reports TLR4 as one of the novel receptors to facilitate the attachment and entry of CHIKV in host macrophages, the TLR4-CHIKV-E2 interactions are essential for efficient viral entry and modulation of infection-induced pro-inflammatory responses in host macrophages, which might have translational implication for designing future therapeutics to regulate the CHIKV infection
Inhibition of IRGM establishes a robust antiviral immune state to restrict pathogenic viruses
The type I interferon (IFN) response is the major host arsenal against invading viruses. IRGM is a negative regulator of IFN responses under basal conditions. However, the role of human IRGM during viral infection has remained unclear. In this study, we show that IRGM expression is increased upon viral infection. IFN responses induced by viral PAMPs are negatively regulated by IRGM. Conversely, IRGM depletion results in a robust induction of key viral restriction factors including IFITMs, APOBECs, SAMHD1, tetherin, viperin, and HERC5/6. Additionally, antiviral processes such as MHC-I antigen presentation and stress granule signaling are enhanced in IRGM-deficient cells, indicating a robust cell-intrinsic antiviral immune state. Consistently, IRGM-depleted cells are resistant to the infection with seven viruses from five different families, including Togaviridae, Herpesviridae, Flaviviverdae, Rhabdoviridae, and Coronaviridae. Moreover, we show that Irgm1 knockout mice are highly resistant to chikungunya virus (CHIKV) infection. Altogether, our work highlights IRGM as a broad therapeutic target to promote defense against a large number of human viruses, including SARS-CoV-2, CHIKV, and Zika virus
Physics Potential of the ICAL detector at the India-based Neutrino Observatory (INO)
The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the
India-based Neutrino Observatory (INO) is designed to study the atmospheric
neutrinos and antineutrinos separately over a wide range of energies and path
lengths. The primary focus of this experiment is to explore the Earth matter
effects by observing the energy and zenith angle dependence of the atmospheric
neutrinos in the multi-GeV range. This study will be crucial to address some of
the outstanding issues in neutrino oscillation physics, including the
fundamental issue of neutrino mass hierarchy. In this document, we present the
physics potential of the detector as obtained from realistic detector
simulations. We describe the simulation framework, the neutrino interactions in
the detector, and the expected response of the detector to particles traversing
it. The ICAL detector can determine the energy and direction of the muons to a
high precision, and in addition, its sensitivity to multi-GeV hadrons increases
its physics reach substantially. Its charge identification capability, and
hence its ability to distinguish neutrinos from antineutrinos, makes it an
efficient detector for determining the neutrino mass hierarchy. In this report,
we outline the analyses carried out for the determination of neutrino mass
hierarchy and precision measurements of atmospheric neutrino mixing parameters
at ICAL, and give the expected physics reach of the detector with 10 years of
runtime. We also explore the potential of ICAL for probing new physics
scenarios like CPT violation and the presence of magnetic monopoles.Comment: 139 pages, Physics White Paper of the ICAL (INO) Collaboration,
Contents identical with the version published in Pramana - J. Physic
Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions
We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe
- …