2,586 research outputs found
Rapidity bin multiplicity correlations from a multi-phase transport model
The central-arbitrary bin and forward-backward bin multiplicity correlation
patterns for Au+Au collisions at = GeV are
investigated within a multi-phase transport (AMPT) model. An interesting
observation is that for GeV Au+Au collisions, these two
correlation patterns both have an increase with the pseudorapidity gap, while
for GeV Au+Au collisions, they decrease. We mainly
discuss the influence of different evolution stages of collision system on the
central-arbitrary bin correlations, such as the initial conditions, partonic
scatterings, hadronization scheme and hadronic scatterings. Our results show
that the central-arbitrary bin multiplicity correlations have different
responses to partonic phase and hadronic phase, which can be suggested as a
good probe to explore the dynamical evolution mechanism of the hot dense matter
in high-energy heavy-ion collisions.Comment: 7pages, 6 figures, accepted for publication in EPJ
Light anti-nuclei production in pp collisions at =7 and 14 TeV
A dynamically constrained coalescence model based on the phase space
quantization and classical limit method was proposed to investigate the
production of light nuclei (anti-nuclei) in non-single diffractive (NSD) pp
collisions at =7 and 14 TeV. This calculation was based on the final
hadronic state in the PYTHIA and PACIAE model simulations, the event sample
consisted of 1.2 events in both simulations. The PACIAE model
calculated yield of 6.247 in NSD pp collisions at
=7 TeV is well comparing with the ALICE rough datum of 5.456. It indicated the reliability of proposed method in some extent. The
yield, transverse momentum distribution, and rapidity distribution of the , , and in NSD pp collisions at
=7 and 14 TeV were predicted by PACIAE and PYTHIA model simulations.
The yield resulted from PACIAE model simulations is larger than the one from
PYTHIA model. This might reflect the role played by the parton and hadron
rescatterings.Comment: 5 pages, 2 figure
Big Data Value Engineering for Business Model Innovation
Big data value engineering for business model innovation requires a drastically different approach as compared with methods for engineering value under existing business models. Taking a Design Science approach, we conducted an exploratory study to formulate the requirements for a method to aid in engineering value via innovation. We then developed a method, called Eco-ARCH (Eco-ARCHitecture) for value discovery. This method is tightly integrated with the BDD (Big Data Design) method for value realization, to form a big data value engineering methodology for addressing these requirements. The Eco-ARCH approach is most suitable for the big data context where system boundaries are fluid, requirements are ill-defined, many stakeholders are unknown, design goals are not provided, no central architecture pre-exists, system behavior is non-deterministic and continuously evolving, and co-creation with consumers and prosumers is essential to achieving innovation goals. The method was empirically validated in collaboration with an IT service company in the Electric Power industry
Distribution of Spectral Lags in Gamma Ray Bursts
Using the data acquired in the Time To Spill (TTS) mode for long gamma-ray
bursts (GRBs) collected by the Burst and Transient Source Experiment on board
the Compton Gamma Ray Observatory (BATSE/CGRO), we have carefully measured
spectral lags in time between the low (25-55 keV) and high (110-320 keV) energy
bands of individual pulses contained in 64 multi-peak GRBs. We find that the
temporal lead by higher-energy gamma-ray photons (i.e., positive lags) is the
norm in this selected sample set of long GRBs. While relatively few in number,
some pulses of several long GRBs do show negative lags. This distribution of
spectral lags in long GRBs is in contrast to that in short GRBs. This apparent
difference poses challenges and constraints on the physical mechanism(s) of
producing long and short GRBs. The relation between the pulse peak count rates
and the spectral lags is also examined. Observationally, there seems to be no
clear evidence for systematic spectral lag-luminosity connection for pulses
within a given long GRB.Comment: 20 pages, 4 figure
The Role of the Lactadherin in Promoting Intestinal DCs Development In Vivo and Vitro
Lactadherin, as one of the immune components in the breast milk, might play a role in the intestinal immune system of newborn. Therefore, we investigated the effect of lactadherin-feeding in early time on the development of intestinal immune system compared with naturally rearing and artificially rearing (non-lactadherin). In the present study, we observed that the Peyer's Patches (PP) from the pups of artificially reared group with lactadherin added were characterized by an excess of OX62+CD4+SIRP+ DC cells and a higher expression of CD3+CD4+CD25+T cells. Additionally, this study also demonstrated that IL-10 production was dramatically increased when lactadherin was present in culture medium compared with lactadherin-absent culture. These results suggested that lactadherin could adjust intestinal DCs activity, induce CD3+CD4+CD25+T cell differentiation, and enhance IL-10 production
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