378 research outputs found
Extensional viscosity of copper nanowire suspensions in an aqueous polymer solution
Suspensions of copper nanowires are emerging as new electronic inks for
next-generation flexible electronics. Using a novel surface acoustic wave
driven extensional flow technique we are able to perform currently lacking
analysis of these suspensions and their complex buffer. We observe extensional
viscosities from 3 mPas (1 mPas shear viscosity) to 37.2
Pas via changes in the suspension concentration, thus capturing low
viscosities that have been historically very challenging to measure. These
changes equate to an increase in the relative extensional viscosity of nearly
12,200 times at a volume fraction of just 0.027. We also find that interactions
between the wires and the necessary polymer additive affect the rheology
strongly. Polymer-induced elasticity shows a reduction as the buffer relaxation
time falls from 819 to 59 s above a critical particle concentration. The
results and technique presented here should aid in the future formulation of
these promising nanowire suspensions and their efficient application as inks
and coatings.Comment: 7 pages, 5 figures, under review for Soft Matter RS
Lignolytic Enzymes of a Mushroom Stereum ostrea Isolated from Wood Logs
Production of lignolytic enzymes by the mushroom fungus Stereum ostrea in liquid medium under conditions of vegetative growth was examined for 10 days in comparison to the reference culture Phanerochaete chrysosporium. Though growth and secretion of extracellular protein by S. ostrea were comparable to those of P. chrysosporium, yields of laccase enzyme by S. ostrea were higher than laccase titres of P. chrysosporium by more than 2 folds on the peak production time interval (IVth day of incubation). S. ostrea yielded titres of 25 units of laccase/ml as against 8.9 units of laccase/ml on the IVth day of incubation. Stereum ostrea also exhibited activities of other lignolytic enzymes, lignin peroxidase (LiP) and manganese peroxidase (MnP), higher than the reference culture. Growth of S. ostrea on the medium in the presence of Remazol orange 16 resulted in the decolourisation of dye, confirming the presence of lignolytic enzymes. S. ostrea appears to be a promising culture with complete lignolytic system
Lepton polarization asymmetry in radiative dileptonic B-meson decays in MSSM
In this paper we study the polarization asymmetries of the final state lepton
in the radiative dileptonic decay of B meson (\bsllg) in the framework of
Minimal Supersymmetric Standard Model (MSSM) and various other unified models
within the framework of MSSM e.g. mSUGRA, SUGRA (where condition of
universality of scalar masses is relaxed) etc. Lepton polarization, in addition
of having a longitudinal component (\pl), can have two other components, \pt
and \pn, lying in and perpendicular to the decay plane, which are proportional
to \ml and hence are significant for final state being or
. We analyse the dependence of these polarization asymmetries
on the parameters of the various models.Comment: typos corrected to match with published versio
B \to K(K^*) missing energy in Unparticle physics
In the present work we study the effects of an unparticle \unpart as the
possible source of missing energy in the decay . We find that the dependence of the differential branching ratio on
the ()-meson's energy in the presence of the vector unparticle
operators is very distinctive from that of the SM. Moreover, in using the
existing upper bound on decays, we have
been able to put more stringent constraints on the parameters of unparticle
stuff.Comment: 13 pages, 5 figure
Lepton polarization correlations in
In this work we will study the polarizations of both leptons () in the
decay channel . In the case of the dileptonic inclusive
decay , where apart from the polarization asymmetries
of single lepton , one can also observe the polarization asymmetries of
both leptons simultaneously. If this sort of measurement is possible then we
can have, apart from decay rate, FB asymmetry and the six single lepton
polarization asymmetries (three each for and ), nine more
double polarization asymmetries. This will give us a very useful tool in more
strict testing of SM and the physics beyond. We discuss the double polarization
asymmetries of leptons in the decay mode within
the SM and the Minimal Supersymmetric extensions of it.Comment: 21 pages, 21 figures; version to match paper to appear in PR
On the asymptotics of higher-dimensional partitions
We conjecture that the asymptotic behavior of the numbers of solid
(three-dimensional) partitions is identical to the asymptotics of the
three-dimensional MacMahon numbers. Evidence is provided by an exact
enumeration of solid partitions of all integers <=68 whose numbers are
reproduced with surprising accuracy using the asymptotic formula (with one free
parameter) and better accuracy on increasing the number of free parameters. We
also conjecture that similar behavior holds for higher-dimensional partitions
and provide some preliminary evidence for four and five-dimensional partitions.Comment: 30 pages, 8 tables, 4 figures (v2) New data (63-68) for solid
partitions added; (v3) published version, new subsection providing an
unbiased estimate of the leading for the leading coefficient added, some
tables delete
Characterisation and bioactivity of oosporein produced by endophytic fungus Cochliobolus kusanoi
Spatially, Temporally and Polarization-Resolved Photoluminescence Exploration of Excitons in Crystalline Phthalocyanine Thin Films
The lack of long range order in organic semiconductor thin films prevents the
unveiling of the complete nature of excitons in optical experiments, because
the diffraction limited beam diameters in the bandgap region far exceed typical
crystalline grain sizes. Here we present spatially-, temporally- and
polarization-resolved dual photoluminescence/linear dichroism microscopy
experiments that investigate exciton states within a single crystalline grain
in solution-processed phthalocyanine thin films. These experiments reveal the
existence of a delocalized singlet exciton, polarized along the high mobility
axis in this quasi-1D electronic system. The strong delocalized {\pi} orbitals
overlap controlled by the molecular stacking along the high mobility axis is
responsible for breaking the radiative recombination selection rules. Using our
linear dichroism scanning microscopy setup we further established a rotation of
molecules (i.e. a structural phase transition) that occurs above 100 K prevents
the observation of this exciton at room temperature.Comment: submitted to Journal of Chem Phys letter
Galectin-9/TIM-3 Interaction Regulates Virus-Specific Primary and Memory CD8+ T Cell Response
In this communication, we demonstrate that galectin (Gal)-9 acts to constrain CD8+ T cell immunity to Herpes Simplex Virus (HSV) infection. In support of this, we show that animals unable to produce Gal-9, because of gene knockout, develop acute and memory responses to HSV that are of greater magnitude and better quality than those that occur in normal infected animals. Interestingly, infusion of normal infected mice with α-lactose, the sugar that binds to the carbohydrate-binding domain of Gal-9 limiting its engagement of T cell immunoglobulin and mucin (TIM-3) receptors, also caused a more elevated and higher quality CD8+ T cell response to HSV particularly in the acute phase. Such sugar treated infected mice also had expanded populations of effector as well as memory CD8+ T cells. The increased effector T cell responses led to significantly more efficient virus control. The mechanisms responsible for the outcome of the Gal-9/TIM-3 interaction in normal infected mice involved direct inhibitory effects on TIM-3+ CD8+ T effector cells as well as the promotion of Foxp3+ regulatory T cell activity. Our results indicate that manipulating galectin signals, as can be achieved using appropriate sugars, may represent a convenient and inexpensive approach to enhance acute and memory responses to a virus infection
Identification of B Cell Epitopes of Alcohol Dehydrogenase Allergen of Curvularia lunata
BACKGROUND/OBJECTIVE: Epitope identification assists in developing molecules for clinical applications and is useful in defining molecular features of allergens for understanding structure/function relationship. The present study was aimed to identify the B cell epitopes of alcohol dehydrogenase (ADH) allergen from Curvularia lunata using in-silico methods and immunoassay. METHOD: B cell epitopes of ADH were predicted by sequence and structure based methods and protein-protein interaction tools while T cell epitopes by inhibitory concentration and binding score methods. The epitopes were superimposed on a three dimensional model of ADH generated by homology modeling and analyzed for antigenic characteristics. Peptides corresponding to predicted epitopes were synthesized and immunoreactivity assessed by ELISA using individual and pooled patients' sera. RESULT: The homology model showed GroES like catalytic domain joined to Rossmann superfamily domain by an alpha helix. Stereochemical quality was confirmed by Procheck which showed 90% residues in most favorable region of Ramachandran plot while Errat gave a quality score of 92.733%. Six B cell (P1-P6) and four T cell (P7-P10) epitopes were predicted by a combination of methods. Peptide P2 (epitope P2) showed E(X)(2)GGP(X)(3)KKI conserved pattern among allergens of pathogenesis related family. It was predicted as high affinity binder based on electronegativity and low hydrophobicity. The computational methods employed were validated using Bet v 1 and Der p 2 allergens where 67% and 60% of the epitope residues were predicted correctly. Among B cell epitopes, Peptide P2 showed maximum IgE binding with individual and pooled patients' sera (mean OD 0.604±0.059 and 0.506±0.0035, respectively) followed by P1, P4 and P3 epitopes. All T cell epitopes showed lower IgE binding. CONCLUSION: Four B cell epitopes of C. lunata ADH were identified. Peptide P2 can serve as a potential candidate for diagnosis of allergic diseases
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