13,887 research outputs found
Activation of TLR3 in keratinocytes increases expression of genes involved in formation of the epidermis, lipid accumulation, and epidermal organelles.
Injury to the skin, and the subsequent release of noncoding double-stranded RNA (dsRNA) from necrotic keratinocytes, has been identified as an endogenous activator of Toll-like receptor 3 (TLR3). As changes in keratinocyte growth and differentiation follow injury, we hypothesized that TLR3 might trigger some elements of the barrier repair program in keratinocytes. dsRNA was observed to induce TLR3-dependent increases in human keratinocyte mRNA abundance for ABCA12 (ATP-binding cassette, sub-family A, member 12), glucocerebrosidase, acid sphingomyelinase, and transglutaminase 1. Additionally, treatment with dsRNA resulted in increases in sphingomyelin and morphologic changes including increased epidermal lipid staining by Oil Red O and TLR3-dependent increases in lamellar bodies and keratohyalin granules. These observations show that dsRNA can stimulate some events in keratinocytes that are important for skin barrier repair and maintenance
Pulses of chaos synchronization in coupled map chains with delayed transmission
Pulses of synchronization in chaotic coupled map lattices are discussed in
the context of transmission of information. Synchronization and
desynchronization propagate along the chain with different velocities which are
calculated analytically from the spectrum of convective Lyapunov exponents.
Since the front of synchronization travels slower than the front of
desynchronization, the maximal possible chain length for which information can
be transmitted by modulating the first unit of the chain is bounded.Comment: 4 pages, 6 figures, updated version as published in PR
The Three Component Electronic Structure of the Cuprates Derived from SI-STM
We present a phenomenological model that describes the low energy electronic
structure of the cuprate high temperature superconductor Bi2Sr2CaCu2O8+x as
observed by Spectroscopic Imagining Scanning Tunneling Microscopy (SI-STM). Our
model is based on observations from Quasiparticle Interference (QPI)
measurements and Local Density of States (LDOS) measurements that span a range
of hole densities from critical doping, p~0.19, to extremely underdoped,
p~0.06. The model presented below unifies the spectral density of states
observed in QPI studies with that of the LDOS. In unifying these two separate
measurements, we find that the previously reported phenomena, the Bogoliubov
QPI termination, the checkerboard conductance modulations, and the pseudogap
are associated with unique energy scales that have features present in both the
q-space and LDOS(E) data sets
Linear-response theory of the longitudinal spin Seebeck effect
We theoretically investigate the longitudinal spin Seebeck effect, in which
the spin current is injected from a ferromagnet into an attached nonmagnetic
metal in a direction parallel to the temperature gradient. Using the fact that
the phonon heat current flows intensely into the attached nonmagnetic metal in
this particular configuration, we show that the sign of the spin injection
signal in the longitudinal spin Seebeck effect can be opposite to that in the
conventional transverse spin Seebeck effect when the electron-phonon
interaction in the nonmagnetic metal is sufficiently large. Our linear-response
approach can explain the sign reversal of the spin injection signal recently
observed in the longitudinal spin Seebeck effect.Comment: Proc. of ICM 2012 (Accepted for publication in J. Korean Phys. Soc.),
typos correcte
Theory of magnon-driven spin Seebeck effect
The spin Seebeck effect is a spin-motive force generated by a temperature
gradient in a ferromagnet that can be detected via normal metal contacts
through the inverse spin Hall effect [K. Uchida {\it et al.}, Nature {\bf 455},
778-781 (2008)]. We explain this effect by spin pumping at the contact that is
proportional to the spin-mixing conductance of the interface, the inverse of a
temperature-dependent magnetic coherence volume, and the difference between the
magnon temperature in the ferromagnet and the electron temperature in the
normal metal [D. J. Sanders and D. Walton, Phys. Rev. B {\bf 15}, 1489 (1977)].Comment: 10 pages, 3 figures, 2 tables. This version is NOT the published PRB
but a version with an erratu
Description of the Immature Stages of Trioza uniqua (Caldwell) (Homoptera: Psyllidae)
The taxonomic position of Trioza uniqua (Caldwell) and its evolutionary affinities with the genera Kuwayama and Trioza are reviewed. Detailed descriptions of the five nymphal instars are given
Parasites Associated with the Leucaena Psyllid, Heteropsylla cubana Crawford, in Hawaii
Four species of parasitoid Hymenoptera have been reared from the Leucaena psyllid, Heteropsylla cubana Crawford, in Hawaii. In addition to the purposely introduced primary parasite Psyllaephagus yaseeni Noyes (Encyrtidae), three species of hyperparasites have been reared. These are a pteromalid, Pachyneuron siphonophorae (Ashmead), and two encyrtids, Syrphophagus aphidivorus (Mayr) and Syrphophagus sp. A key to parasitoids reared from H. cubana in Hawaii is presented
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