75,561 research outputs found
A novel octopamine receptor with preferential expression in <i>Drosophila</i> mushroom bodies
Octopamine is a neuromodulator that mediates diverse physiological processes in invertebrates. In some insects, such as honeybees and fruit flies, octopamine has been shown to be a major stimulator of adenylyl cyclase and to function in associative learning. To identify an octopamine receptor mediating this function in Drosophila, putative biogenic amine receptors were cloned by a novel procedure using PCR and single-strand conformation polymorphism. One new receptor, octopamine receptor in mushroom bodies (OAMB), was identified as an octopamine receptor because human and Drosophila cell lines expressing OAMB showed increased cAMP and intracellular Ca2+ levels after octopamine application. Immunohistochemical analysis using an antibody made to the receptor revealed highly enriched expression in the mushroom body neuropil and the ellipsoid body of central complex, brain areas known to be crucial for olfactory learning and motor control, respectively. The preferential expression of OAMB in mushroom bodies and its capacity to produce cAMP accumulation suggest an important role in synaptic modulation underlying behavioral plasticity
Reworking the Tucson-Melbourne Three-Nucleon Potential
We introduce new values of the strength constants (i.e., , , , and
coefficients) of the Tucson-Melbourne (TM) 2 exchange three nucleon
potential. The new values come from contemporary dispersion relation analyses
of meson factory N scattering data. We make variational Monte Carlo
calculations of the triton with the original and updated three-body forces to
study the effects of this update. We remove a short-range -- -range part
of the potential due to the coefficient and discuss the effect on the
triton binding energy.Comment: 12 pages, to appear in Few-Body System
Induced Magnetic Ordering by Proton Irradiation in Graphite
We provide evidence that proton irradiation of energy 2.25 MeV on
highly-oriented pyrolytic graphite samples triggers ferro- or ferrimagnetism.
Measurements performed with a superconducting quantum interferometer device
(SQUID) and magnetic force microscopy (MFM) reveal that the magnetic ordering
is stable at room temperature.Comment: 3 Figure
Protein transduction: A novel tool for tissue regeneration
Tissue regeneration in humans is limited and excludes vitals organs like heart and brain. Transformation experiments with oncogenes like T antigen have shown that retrodifferentiation of the respective cells is possible but hard to control. To bypass the risk of cancer formation a protein therapy approach has been developed. The transient delivery of proteins rather than genes could still induce terminallydifferentiated cells to reenter the cell cycle. This approach takes advantage of proteintransducing domains that mediate the transfer of cargo proteins into cells. The goal of this brief review is to outline the basics of protein transduction and to discuss potential applications for tissue regeneration
Single-Electron Traps: A Quantitative Comparison of Theory and Experiment
We have carried out a coordinated experimental and theoretical study of
single-electron traps based on submicron aluminum islands and aluminum oxide
tunnel junctions. The results of geometrical modeling using a modified version
of MIT's FastCap were used as input data for the general-purpose
single-electron circuit simulator MOSES. The analysis indicates reasonable
quantitative agreement between theory and experiment for those trap
characteristics which are not affected by random offset charges. The observed
differences between theory and experiment (ranging from a few to fifty percent)
can be readily explained by the uncertainty in the exact geometry of the
experimental nanostructures.Comment: 17 pages, 21 figures, RevTex, eps
On QGP Formation in pp Collisions at 7 TeV
The possibility of QGP formation in central pp collisions at ultra-high
collision energy is discussed. Centrality-dependent \pt-spectra and
(pseudo)rapidity spectra of thermal photons (charged hadrons) from pp
collisions at 7 TeV are presented (addressed). Minimal-bias \pt-spectrum of
direct photons and charged hadrons is compared under the framework with and
without hydrodynamical evolution process.Comment: 4pages, 5figs, submitted to the Proceedings of the 22nd International
Conference on Ultra-relativistic Nucleus-Nucleus Collision (Quark Matter
2011), 23 - 28 May 2011, Annecy, Franc
Assessment of different urban traffic control strategy impacts on vehicle emissions
This paper investigates the influence of traffic signal control strategy on vehicle emissions, vehicle journey time and total throughput flow within a single isolated four-armed junction. Two pre-timed signal plans are considered, one with two-stages involving permissive-only opposing turns and the other with four-stages which has no conflicting traffic. Additionally, the increase in efficiency by utilising actuated signal timing where green time is re-optimised as flow values vary is investigated. A microscopic traffic simulation model is used to model flows and AIRE (Analysis of Instantaneous Road Emissions) microscopic emissions model is utilised to out- put emission levels from the flow data. A simple junction model shows that the two-stage signal plan is more efficient in both emis- sions and journey time. However, as the level of opposed turning vehicles and conflicting movement increases, the two-stage model moves to being the inferior signal plan choice and the four-stage plan outputs fewer emissions than the two-stage plan. A real-world example of a four-armed junction has been used in this study and from the traffic survey data and existing junction layout; it is rec- ommended that a two-stage plan is used as it produces lower amounts of emissions and shorter journey times compared to a four-stage plan. The results also show that nitrogen oxides (NOx) are the most sensitive to changes in flow followed by carbon dioxide (CO2), Black Carbon and then particulate matter (PM10)
Resummation Effects in Vector-Boson and Higgs Associated Production
Fixed-order QCD radiative corrections to the vector-boson and Higgs
associated production channels, pp -> VH (V=W, Z), at hadron colliders are well
understood. We combine higher order perturbative QCD calculations with
soft-gluon resummation of both threshold logarithms and logarithms which are
important at low transverse momentum of the VH pair. We study the effects of
both types of logarithms on the scale dependence of the total cross section and
on various kinematic distributions. The next-to-next-to-next-to-leading
logarithmic (NNNLL) resummed total cross sections at the LHC are almost
identical to the fixed-order perturbative next-to-next-to-leading order (NNLO)
rates, indicating the excellent convergence of the perturbative QCD series.
Resummation of the VH transverse momentum (p_T) spectrum provides reliable
results for small values of p_T and suggests that implementing a jet-veto will
significantly decrease the cross sections.Comment: 25 pages, references update
Cooperative Secure Transmission by Exploiting Social Ties in Random Networks
Social awareness and social ties are becoming increasingly popular with
emerging mobile and handheld devices. Social trust degree describing the
strength of the social ties has drawn lots of research interests in many fields
in wireless communications, such as resource sharing, cooperative communication
and so on. In this paper, we propose a hybrid cooperative beamforming and
jamming scheme to secure communication based on the social trust degree under a
stochastic geometry framework. The friendly nodes are categorized into relays
and jammers according to their locations and social trust degrees with the
source node. We aim to analyze the involved connection outage probability (COP)
and secrecy outage probability (SOP) of the performance in the networks. To
achieve this target, we propose a double Gamma ratio (DGR) approach through
Gamma approximation. Based on this, the COP and SOP are tractably obtained in
closed-form. We further consider the SOP in the presence of Poisson Point
Process (PPP) distributed eavesdroppers and derive an upper bound. The
simulation results verify our theoretical findings, and validate that the
social trust degree has dramatic influences on the security performance in the
networks.Comment: 30 pages, 11 figures, to be published in IEEE Transactions on
Communication
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