10,071 research outputs found
Impact of Pulp on the Chemical Profile of Mango Wine
The aim of this study was to assess the effect of mango pulp inclusion (which mimicked the maceration stepin grape wine fermentation) on the fermentation dynamics and chemical profile of mango wine, especiallythe volatiles. The growth of Saccharomyces cerevisiae MERIT.ferm was slower in the mango juice with pulp(uncentrifuged juice), with a corresponding slower reduction in °Brix, relative to the juice without pulp(centrifuged juice). The utilisation of glucose, fructose and sucrose was similar in both uncentrifuged andcentrifuged juices, with almost complete consumption. Citric, tartaric, malic, pyruvic and succinic acidwere the major organic acids in the wines fermented from both the uncentrifuged and centrifuged juices.Citric acid decreased slightly in the macerated wine. Tartaric and malic acid decreased in both wines.Pyruvic acid increased slightly and succinic acid remained almost constant in both wines. Monoterpenes,as one of the signature aroma compounds in mango juice, decreased dramatically in both wines, but wereten times higher in the macerated wine. Terpenols were at least four times higher in the macerated wine.The macerated wine also produced higher levels of fusel alcohols and acetate esters compared to the nonmaceratedwine. On the other hand, the non-macerated wine possessed a higher concentration of mediumchainfatty acids and corresponding ethyl esters. This study indicates that the inclusion of pulp in mangowine fermentation would contribute to the aroma complexity
Upconversion Nanoparticle-Based Cell Membrane-Coated cRGD Peptide Bioorthogonally Labeled Nanoplatform for Glioblastoma Treatment
Glioblastoma is hard to be eradicated partly because of the obstructive blood-brain barrier (BBB) and the dynamic autophagy activities of glioblastoma. Here, hydroxychloroquine (HDX)-loaded yolk-shell upconversion nanoparticle (UCNP)@Zn0.5Cd0.5S nanoparticle coating with the cyclic Arg-Gly-Asp (cRGD)-grafted glioblastoma cell membrane for near-infrared (NIR)-triggered treatment of glioblastoma is prepared for the first time. [email protected] (abbreviated as YSN, yolk-shell nanoparticle) under NIR radiation will generate reactive oxygen species for imposing cytotoxicity. HDX, the only available autophagy inhibitor in clinical studies, can enhance cytotoxicity by preventing damaged organelles from being recycled. The cRGD-decorated cell membrane allowed the HDX-loaded nanoparticles to efficiently bypass the BBB and specifically target glioblastoma cells. Exceptional treatment efficacy of the NIR-triggered chemotherapy and photodynamic therapy was achieved in U87 cells and in the mouse glioblastoma model as well. Our results provided proof-of-concept evidence that HDX@YSN@CCM@cRGD could overcome the delivery barriers and achieve targeted treatment of glioblastoma
Protective Enterotoxigenic Escherichia coli Antigens in a Murine Intranasal Challenge Model
Citation: Kumar, A., Hays, M., Lim, F., Foster, L. J., Zhou, M. X., Zhu, G. Q., . . . Hardwidge, P. R. (2015). Protective Enterotoxigenic Escherichia coli Antigens in a Murine Intranasal Challenge Model. Plos Neglected Tropical Diseases, 9(8), 16. doi:10.1371/journal.pntd.0003924Enterotoxigenic Escherichia coli (ETEC) is an endemic health threat in underdeveloped nations. Despite the significant effort extended to vaccine trials using ETEC colonization factors, these approaches have generally not been especially effective in mediating cross-protective immunity. We used quantitative proteomics to identify 24 proteins that differed in abundance in membrane protein preparations derived from wild-type vs. a type II secretion system mutant of ETEC. We expressed and purified a subset of these proteins and identified nine antigens that generated significant immune responses in mice. Sera from mice immunized with either the MltA-interacting protein MipA, the periplasmic chaperone seventeen kilodalton protein, Skp, or a long-chain fatty acid outer membrane transporter, ETEC_2479, reduced the adherence of multiple ETEC strains differing in colonization factor expression to human intestinal epithelial cells. In intranasal challenge assays of mice, immunization with ETEC_ 2479 protected 88% of mice from an otherwise lethal challenge with ETEC H10407. Immunization with either Skp or MipA provided an intermediate degree of protection, 68 and 64%, respectively. Protection was significantly correlated with the induction of a secretory immunoglobulin A response. This study has identified several proteins that are conserved among heterologous ETEC strains and may thus potentially improve cross- protective efficacy if incorporated into future vaccine designs
Influence of Arctic sea ice on European summer precipitation
Copyright © 2013 IOP Publishing Ltd. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence (http://creativecommons.org/licenses/by/3.0/). Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.Open Access journalThe six summers from 2007 to 2012 were all wetter than average over northern Europe. Although none of these individual events are unprecedented in historical records, the sequence of six consecutive wet summers is extraordinary. Composite analysis reveals that observed wet summer months in northern Europe tend to occur when the jet stream is displaced to the south of its climatological position, whereas dry summer months tend to occur when the jet stream is located further north. Highly similar mechanisms are shown to drive simulated precipitation anomalies in an atmospheric model. The model is used to explore the influence of Arctic sea ice on European summer climate, by prescribing different sea ice conditions, but holding other forcings constant. In the simulations, Arctic sea ice loss induces a southward shift of the summer jet stream over Europe and increased northern European precipitation. The simulated precipitation response is relatively small compared to year-to-year variability, but is statistically significant and closely resembles the spatial pattern of precipitation anomalies in recent summers. The results suggest a causal link between observed sea ice anomalies, large-scale atmospheric circulation and increased summer rainfall over northern Europe. Thus, diminished Arctic sea ice may have been a contributing driver of recent wet summers.UK Natural Environment Research Council (NERC
Duality Cascade in Brane Inflation
We show that brane inflation is very sensitive to tiny sharp features in
extra dimensions, including those in the potential and in the warp factor. This
can show up as observational signatures in the power spectrum and/or
non-Gaussianities of the cosmic microwave background radiation (CMBR). One
general example of such sharp features is a succession of small steps in a
warped throat, caused by Seiberg duality cascade using gauge/gravity duality.
We study the cosmological observational consequences of these steps in brane
inflation. Since the steps come in a series, the prediction of other steps and
their properties can be tested by future data and analysis. It is also possible
that the steps are too close to be resolved in the power spectrum, in which
case they may show up only in the non-Gaussianity of the CMB temperature
fluctuations and/or EE polarization. We study two cases. In the slow-roll
scenario where steps appear in the inflaton potential, the sensitivity of brane
inflation to the height and width of the steps is increased by several orders
of magnitude comparing to that in previously studied large field models. In the
IR DBI scenario where steps appear in the warp factor, we find that the
glitches in the power spectrum caused by these sharp features are generally
small or even unobservable, but associated distinctive non-Gaussianity can be
large. Together with its large negative running of the power spectrum index,
this scenario clearly illustrates how rich and different a brane inflationary
scenario can be when compared to generic slow-roll inflation. Such distinctive
stringy features may provide a powerful probe of superstring theory.Comment: Corrections in Eq.(5.47), Eq (5.48), Eq(5.49) and Fig
Reversible room-temperature ferromagnetism in Nb-doped SrTiO3 single crystals
The search for oxide-based room-temperature ferromagnetism has been one of
the holy grails in condensed matter physics. Room-temperature ferromagnetism
observed in Nb-doped SrTiO3 single crystals is reported in this Rapid
Communication. The ferromagnetism can be eliminated by air annealing (making
the samples predominantly diamagnetic) and can be recovered by subsequent
vacuum annealing. The temperature dependence of magnetic moment resembles the
temperature dependence of carrier density, indicating that the magnetism is
closely related to the free carriers. Our results suggest that the
ferromagnetism is induced by oxygen vacancies. In addition, hysteretic
magnetoresistance was observed for magnetic field parallel to current,
indicating that the magnetic moments are in the plane of the samples. The x-ray
photoemission spectroscopy, the static time-of-flight and the dynamic secondary
ion mass spectroscopy and proton induced x-ray emission measurements were
performed to examine magnetic impurities, showing that the observed
ferromagnetism is unlikely due to any magnetic contaminant.Comment: 6 pages, 6 figure
Cyclic cosmology from Lagrange-multiplier modified gravity
We investigate cyclic and singularity-free evolutions in a universe governed
by Lagrange-multiplier modified gravity, either in scalar-field cosmology, as
well as in one. In the scalar case, cyclicity can be induced by a
suitably reconstructed simple potential, and the matter content of the universe
can be successfully incorporated. In the case of -gravity, cyclicity can
be induced by a suitable reconstructed second function of a very
simple form, however the matter evolution cannot be analytically handled.
Furthermore, we study the evolution of cosmological perturbations for the two
scenarios. For the scalar case the system possesses no wavelike modes due to a
dust-like sound speed, while for the case there exist an oscillation
mode of perturbations which indicates a dynamical degree of freedom. Both
scenarios allow for stable parameter spaces of cosmological perturbations
through the bouncing point.Comment: 8 pages, 3 figures, references added, accepted for publicatio
Comparing Brane Inflation to WMAP
We compare the simplest realistic brane inflationary model to recent
cosmological data, including WMAP 3-year cosmic microwave background (CMB)
results, Sloan Digital Sky Survey luminous red galaxies (SDSS LRG) power
spectrum data and Supernovae Legacy Survey (SNLS) Type 1a supernovae distance
measures. Here, the inflaton is simply the position of a -brane which is
moving towards a -brane sitting at the bottom of a throat (a warped,
deformed conifold) in the flux compactified bulk in Type IIB string theory. The
analysis includes both the usual slow-roll scenario and the Dirac-Born-Infeld
scenario of slow but relativistic rolling. Requiring that the throat is inside
the bulk greatly restricts the allowed parameter space. We discuss possible
scenarios in which large tensor mode and/or non-Gaussianity may emerge. Here,
the properties of a large tensor mode deviate from that in the usual slow-roll
scenario, providing a possible stringy signature. Overall, within the brane
inflationary scenario, the cosmological data is providing information about the
properties of the compactification of the extra dimensions.Comment: 45 pages 11 figure
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