620 research outputs found
CD14-dependent lipopolysaccharide-induced ÎČ-defensin-2 expression in human tracheobronchial epithelium
The induction of host antimicrobial molecules following binding of pathogen components to pattern recognition receptors such as CD14 and the Toll-like receptors (TLRs) is a key feature of innate immunity. The human airway epithelium is an important environmental interface, but LPS recognition pathways have not been determined. We hypothesized that LPS would trigger ÎČ-defensin (hBD2) mRNA in human tracheobronchial epithelial (hTBE) cells through a CD14-dependent mechanism, ultimately activating NF-ÎșB. An average 3-fold increase in hBD2 mRNA occurs 24 h after LPS challenge of hTBE cells. For the first time, we demonstrate the presence of CD14 mRNA and cell surface protein in hTBE cells and show that CD14 neutralization abolishes LPS induction of hBD2 mRNA. Furthermore, we demonstrate TLR mRNA in hTBE cells and NF-ÎșB activation following LPS. Thus, LPS induction of hBD2 in hTBE cells requires CD14, which may complex with a TLR to ultimately activate NF-ÎșB
Argonaute2 regulates the pancreatic ÎČ-cell secretome
Argonaute2 (Ago2) is an established component of the microRNA-induced silencing complex. Similar to miR-375 loss-of-function studies, inhibition of Ago2 in the pancreatic beta-cell resulted in enhanced insulin release underlining the relationship between these two genes. Moreover, as the most abundant microRNA in pancreatic endocrine cells, miR-375 was also observed to be enriched in Ago2-associated complexes. Both Ago2 and miR-375 regulate the pancreatic beta-cell secretome and we identified using quantitative mass spectrometry the enhanced release of a set of proteins or secretion signature in response to a glucose stimulus using the murine beta-cell line, MIN6. In addition, loss of Ago2 resulted in the increased expression of miR-375 target genes, including gephyrin and ywhaz. These targets positively contribute to exocytosis indicating they may mediate the functional role of both miR-375 and Ago proteins in the pancreatic beta-cell by influencing the secretory pathway. This study specifically addresses the role of Ago2 in the systemic release of proteins from beta-cells and highlights the contribution of the microRNA pathway to the function of this cell type
Ginzburg-Landau functional for nearly antiferromagnetic perfect and disordered Kondo lattices
Interplay between Kondo effect and trends to antiferromagnetic and spin glass
ordering in perfect and disordered bipartite Kondo lattices is considered.
Ginzburg-Landau equation is derived from the microscopic effective action
written in three mode representation (Kondo screening, antiferromagnetic
correlations and spin liquid correlations). The problem of local constraint is
resolved by means of Popov-Fedotov representation for localized spin operators.
It is shown that the Kondo screening enhances the trend to a spin liquid
crossover and suppresses antiferromagnetic ordering in perfect Kondo lattices
and spin glass ordering in doped Kondo lattices. The modified Doniach's diagram
is constructed, and possibilities of going beyond the mean field approximation
are discussed.Comment: 18 pages, RevTeX, 7 EPS figures include
Effects observed in the Latin American sector ionospheric F region during the intense geomagnetic disturbances in the early part of November 2004
The Sun was very active in the early part of November 2004. During the period of 8-10 November 2004, intense geomagnetic disturbances with two superstorms were observed. In this paper, we have investigated the generation and suppression of equatorial ionospheric irregularities and the daytime changes in the F region electron density in the Latin American sector during the period of intense geomagnetic disturbances. We present the ionospheric sounding observations carried out at Manaus and Sao Jose dos Campos, Brazil, during this geomagnetically disturbed period. Also, GPS observations obtained from several stations in Brazil, Argentina, and St. Croix, U.S. Virgin Islands, during the disturbed period are presented. During the main phase of the first superstorm, around the prereversal enhancement time (night of 7-8 November), prompt penetration of electric field was observed and the presence of equatorial ionospheric irregularities was detected from St. Croix, U.S. Virgin Islands (in the northern hemisphere) to Bahia Blanca, Argentina (in the southern hemisphere). The ionospheric sounding observations at Manaus indicate inhibition of prereversal enhancement on the nights of 9-10 and 10-11 November, possibly due to the disturbed thermospheric winds or disturbance electric fields. Virtually no phase fluctuations on the nights of 9-10 and 10-11 November were observed in the Latin American sector. During the daytime on 8 November, the vertical total electron content (VTEC) observations show a negative storm phase at Porto Alegre (Brazil) and Bahia Blanca (Argentina). Again during the daytime on 10 November, the VTEC observations show a negative storm phase from Brasilia (Brazil) to Bahia Blanca. These negative storm phases are associated with a decrease in the O/N2 ratio. During the daytime on 9 November, the VTEC observations show a positive storm phase extending from St. Croix to Porto Alegre, and again on 10 November, VTEC observations show a positive storm phase. These positive storm phases observed are possibly due to changes in large-scale wind circulation and an increase in the O/N2 ratio.Facultad de Ciencias AstronĂłmicas y GeofĂsica
Effects observed in the Latin American sector ionospheric F region during the intense geomagnetic disturbances in the early part of November 2004
The Sun was very active in the early part of November 2004. During the period of 8-10 November 2004, intense geomagnetic disturbances with two superstorms were observed. In this paper, we have investigated the generation and suppression of equatorial ionospheric irregularities and the daytime changes in the F region electron density in the Latin American sector during the period of intense geomagnetic disturbances. We present the ionospheric sounding observations carried out at Manaus and Sao Jose dos Campos, Brazil, during this geomagnetically disturbed period. Also, GPS observations obtained from several stations in Brazil, Argentina, and St. Croix, U.S. Virgin Islands, during the disturbed period are presented. During the main phase of the first superstorm, around the prereversal enhancement time (night of 7-8 November), prompt penetration of electric field was observed and the presence of equatorial ionospheric irregularities was detected from St. Croix, U.S. Virgin Islands (in the northern hemisphere) to Bahia Blanca, Argentina (in the southern hemisphere). The ionospheric sounding observations at Manaus indicate inhibition of prereversal enhancement on the nights of 9-10 and 10-11 November, possibly due to the disturbed thermospheric winds or disturbance electric fields. Virtually no phase fluctuations on the nights of 9-10 and 10-11 November were observed in the Latin American sector. During the daytime on 8 November, the vertical total electron content (VTEC) observations show a negative storm phase at Porto Alegre (Brazil) and Bahia Blanca (Argentina). Again during the daytime on 10 November, the VTEC observations show a negative storm phase from Brasilia (Brazil) to Bahia Blanca. These negative storm phases are associated with a decrease in the O/N2 ratio. During the daytime on 9 November, the VTEC observations show a positive storm phase extending from St. Croix to Porto Alegre, and again on 10 November, VTEC observations show a positive storm phase. These positive storm phases observed are possibly due to changes in large-scale wind circulation and an increase in the O/N2 ratio.Facultad de Ciencias AstronĂłmicas y GeofĂsica
Mystify me: Coke, terror and the symbolic immortality boost
A panel on âMarketing as Mystificationâ convened at the 2011 Academy of Marketing conference in Liverpool. Ideas from the Liverpool event were supplemented by commentaries from selected other authors. Each commentary explores the aspects of âmystificationâ observable in marketing discourses and practices. In what follows, Laufer interprets marketing mystification as modern form of sophism, Dholakia and Firat discuss mystifying ways that inequality is marketed, Varman analyzes the perversion and mystification of âdevelopmentâ via neoliberal marketing of âsocial entrepreneurship,â Mikkonen explores mystifying marketing representations of gays and lesbians, and Freund and Jacobi present a fascinating interpretation of how Coca-Cola advertising mystically reassures us that our difficult, dangerous lifeworld is actually quite hunky-dory. </jats:p
Nucleon Charge and Magnetization Densities from Sachs Form Factors
Relativistic prescriptions relating Sachs form factors to nucleon charge and
magnetization densities are used to fit recent data for both the proton and the
neutron. The analysis uses expansions in complete radial bases to minimize
model dependence and to estimate the uncertainties in radial densities due to
limitation of the range of momentum transfer. We find that the charge
distribution for the proton is significantly broad than its magnetization
density and that the magnetization density is slightly broader for the neutron
than the proton. The neutron charge form factor is consistent with the Galster
parametrization over the available range of Q^2, but relativistic inversion
produces a softer radial density. Discrete ambiguities in the inversion method
are analyzed in detail. The method of Mitra and Kumari ensures compatibility
with pQCD and is most useful for extrapolating form factors to large Q^2.Comment: To appear in Phys. Rev. C. Two new figures and accompanying text have
been added and several discussions have been clarified with no significant
changes to the conclusions. Now contains 47 pages including 21 figures and 2
table
Au+Au Reactions at the AGS: Experiments E866 and E917
Particle production and correlation functions from Au+Au reactions have been
measured as a function of both beam energy (2-10.7AGeV) and impact parameter.
These results are used to probe the dynamics of heavy-ion reactions, confront
hadronic models over a wide range of conditions and to search for the onset of
new phenomena.Comment: 12 pages, 14 figures, Talk presented at Quark Matter '9
Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory
Data from the Pierre Auger Observatory are analyzed to search for
anisotropies near the direction of the Galactic Centre at EeV energies. The
exposure of the surface array in this part of the sky is already significantly
larger than that of the fore-runner experiments. Our results do not support
previous findings of localized excesses in the AGASA and SUGAR data. We set an
upper bound on a point-like flux of cosmic rays arriving from the Galactic
Centre which excludes several scenarios predicting sources of EeV neutrons from
Sagittarius . Also the events detected simultaneously by the surface and
fluorescence detectors (the `hybrid' data set), which have better pointing
accuracy but are less numerous than those of the surface array alone, do not
show any significant localized excess from this direction.Comment: Matches published versio
Measurement of W Polarisation at LEP
The three different helicity states of W bosons produced in the reaction e+
e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W
decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to
measure the polarisation of W bosons, and its dependence on the W boson
production angle. The fraction of longitudinally polarised W bosons is measured
to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and
the second systematic, in agreement with the Standard Model expectation
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