4,955 research outputs found
Possibly New Charmed Baryon States from Decay
We examine the invariant mass spectrum of in decay measured by BABAR and find that through the 2-step processes of
, where denotes a
charmed baryon state, some of the peaks can be identified with the established
, and . Moreover, in
order to account for the measured spectrum, it is necessary to introduce a new
charmed baryon resonance with MeV.Comment: 8 pages, 1 figure, title changed and discussions updated, version
accepted for publication in Phys. Rev.
Activation of the maternal immune system induces endocrine changes in the placenta via IL-6
Activation of the maternal immune system in rodent models sets in motion a cascade of molecular pathways that ultimately result in autism- and schizophrenia-related behaviors in offspring. The finding that interleukin-6 (IL-6) is a crucial mediator of these effects led us to examine the mechanism by which this cytokine influences fetal development in vivo. Here we focus on the placenta as the site of direct interaction between mother and fetus and as a principal modulator of fetal development. We find that maternal immune activation (MIA) with a viral mimic, synthetic double-stranded RNA (poly(I:C)), increases IL-6 mRNA as well as maternally-derived IL-6 protein in the placenta. Placentas from MIA mothers exhibit increases in CD69+ decidual macrophages, granulocytes and uterine NK cells, indicating elevated early immune activation. Maternally-derived IL-6 mediates activation of the JAK/STAT3 pathway specifically in the spongiotrophoblast layer of the placenta, which results in expression of acute phase genes. Importantly, this parallels an IL-6-dependent disruption of the growth hormone-insulin-like growth factor (GH-IGF) axis that is characterized by decreased GH, IGFI and IGFBP3 levels. In addition, we observe an IL-6-dependent induction in pro-lactin-like protein-K (PLP-K) expression as well as MIA-related alterations in other placental endocrine factors. Together, these IL-6-mediated effects of MIA on the placenta represent an indirect mechanism by which MIA can alter fetal development
Concurrent Design Strategy in Modeling and Structure of Electric Scooter for Young Disabilities
Disabled people often use the electric scooter as a means of transport. However, the electric scooter designed for disabilities is too bulky and not light in shape. It is not only awkward on the road but brings inconvenience to young people with disabilities. In the first phase of the study, first the electric scooter with a higher market share as a design reference was collected; then we use the image scale analysis to determine the market position of the electric scooter. Combine each major component and derive detail design of the product through Morphological chart method and Finite Structure Method (FSM). This study uses this method to complete the development of product modeling and analyze the configuration of the product as the main function in the structural and main function in space. Let function and appearance have the efficient combination. Then use Analytic Hierarchy Process (AHP) to obtain objective decision results. The use of Concurrent Design Strategy can effectively shorten the development process and increase the chance of product success.
Keywords: concurrent design, electric scooter, morphological chart method, finite structure method, analytical hierarchy proces
Equivalent approaches for two-body anti-triplet charmed baryon decays
For the two-body anti-triplet charmed baryon decays, there exist two
theoretical analyses based on the flavor () symmetry. One is
the irreducible approach (IRA), which depends on the irreducible
representation of the effective Hamiltonian. The other is the
topological-diagram approach (TDA), where the decays are drawn to consist of
-boson emission and -boson exchange topologies. We demonstrate that IRA
and TDA can be equivalent, such that the IRA parameters can be seen to mix with
the TDA topologies. The current observations of might cause theoretical difficulties. With the
symmetry breaking, we explain . It is
found that a specific -boson exchange topology denoted by only appears
in , by which we explain . In addition, we predict for future
measurements to test if can be a significant contribution.Comment: 13 pages, 7 tables, 1 figure, introduction rephrased, reference
added, typos correcte
Pictorial approach for two-body weak decays
We explore two-body non-leptonic weak decays of into final
states and , where denotes an
octet (a decuplet) baryon, and represents a pseudoscalar (vector) meson.
Based on the flavor symmetry, we depict and parameterize
the -emission and -exchange processes using the topological diagram
approach, establishing strict relations for possible decay channels.
We identify dominant topological parameters, determined by available data,
allowing us to explain the experimental ratios , , and . We also calculate the branching fractions of the
Cabibbo-allowed decays, such as . In particular, we establish
approximate isospin relations: and , where
is accessible
to the Belle and LHCb experiments.Comment: 16 pages, 3 tables, 2 figure
How Much Does Money Matter in a Direct Democracy?
The fine-structure splitting of quantum confined InxGa1-x Nexcitons is investigated using polarization-sensitive photoluminescence spectroscopy. The majority of the studied emission lines exhibits mutually orthogonal fine-structure components split by 100-340 mu eV, as measured from the cleaved edge of the sample. The exciton and the biexciton reveal identical magnitudes but reversed sign of the energy splitting.Original Publication:Supaluck Amloy, Y T Chen, K F Karlsson, K H Chen, H C Hsu, C L Hsiao, L C Chen and Per-Olof Holtz, Polarization-resolved fine-structure splitting of zero-dimensional InxGa1-xN excitons, 2011, PHYSICAL REVIEW B, (83), 20, 201307.http://dx.doi.org/10.1103/PhysRevB.83.201307Copyright: American Physical Societyhttp://www.aps.org
Near-IR studies of recurrent nova V745 Scorpii during its 2014 outburst
The recurrent nova (RN) V745 Scorpii underwent its third known outburst on
2014 February 6. Infrared monitoring of the eruption on an almost daily basis,
starting from 1.3d after discovery, shows the emergence of a powerful blast
wave generated by the high velocity nova ejecta exceeding 4000 kms
plowing into its surrounding environment. The temperature of the shocked gas is
raised to a high value exceeding 10K immediately after outburst
commencement. The energetics of the outburst clearly surpass those of similar
symbiotic systems like RS Oph and V407 Cyg which have giant secondaries. The
shock does not show a free-expansion stage but rather shows a decelerative
Sedov-Taylor phase from the beginning. Such strong shockfronts are known to be
sites for ray generation. V745 Sco is the latest nova, apart from five
other known novae, to show ray emission. It may be an important
testbed to resolve the crucial question whether all novae are generically
ray emitters by virtue of having a circumbinary reservoir of material
that is shocked by the ejecta rather than ray generation being
restricted to only symbiotic systems with a shocked red giant (RG) wind. The
lack of a free-expansion stage favors V745 Sco to have a density enhancement
around the white dwarf (WD), above that contributed by a RG wind. Our analysis
also suggests that the WD in V745 Sco is very massive and a potential
progenitor for a future SN Ia explosion.Comment: To appear in ApJ (Letters
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