1,573 research outputs found
Dynamics of opinion formation in a small-world network
The dynamical process of opinion formation within a model using a local
majority opinion updating rule is studied numerically in networks with the
small-world geometrical property. The network is one in which shortcuts are
added to randomly chosen pairs of nodes in an underlying regular lattice. The
presence of a small number of shortcuts is found to shorten the time to reach a
consensus significantly. The effects of having shortcuts in a lattice of fixed
spatial dimension are shown to be analogous to that of increasing the spatial
dimension in regular lattices. The shortening of the consensus time is shown to
be related to the shortening of the mean shortest path as shortcuts are added.
Results can also be translated into that of the dynamics of a spin system in a
small-world network.Comment: 10 pages, 5 figure
Changes in endogenous hormone concentrations during inflorescence induction and development in pineapple (Ananas comosus cv. Smooth Cayenne) by ethephon
This study investigated the changes of five endogenous hormones in the shoot apex and the white bases of D-leaf during the inflorescence induction and development of ‘Smooth Cayenne’ pineapple, using 14-month-old pot-grown plants as material and ethephon as flower forcing agent. Results showed that application of ethephon increased the level of endogenous ethylene (C2H4), abscisic acid (ABA) and 2-isopentyl adenine (2-iP) while it decreased the concentration of indole-3-acetic acid (IAA), gibberellic acid (GA3) and zeatin (ZT), and led to the transition of vegetative growth to inflorescence initiation. After inflorescence initiation, the contents of C2H4, ABA and 2-iP declined but the contents of IAA, ABA and ZT increased. These results indicated that low levels of IAA, GA3 and ZT and high levels of C2H4, ABA and 2-iP facilitated inflorescence initiation, while high levels of ZT, IAA and GA3 and low levels of C2H4 and ABA facilitated inflorescence development.Key words: Pineapple, inflorescence initiation, inflorescence development, endogenous hormone
Quantum transport through a double Aharonov-Bohm-interferometer in the presence of Andreev reflection
Quantum transport through a double Aharonov-Bohm-interferometer in the
presence of Andreev reflection is investigated in terms of the nonequilibrium
Green function method with which the reflection current is obtained. Tunable
Andreev reflection probabilities depending on the interdot coupling strength
and magnetic flux as well are analysised in detail. It is found that the
oscillation period of the reflection probability with respect to the magnetic
flux for the double interferometer depends linearly on the ratio of two parts
magnetic fluxes n, i.e. 2(n+1)pi, while that of a single interferometer is 2pi.
The coupling strength not only affects the height and the linewidth of Andreev
reflection current peaks vs gate votage but also shifts the peak positions. It
is furthermore demonstrated that the Andreev reflection current peaks can be
tuned by the magnetic fluxes.Comment: 13 pages, 12 figur
QCD quark cyclobutadiene and light tetraquark spectrum
The QCD quark cyclobutadiene (ring-like), a new color structure of tetraquark
system, is proposed and studied in the flux tube model with multi-body
confinement potential. The QCD quark cyclobutadiene and other flux tube
structures of tetraquark states have similar energies and they can be regarded
as QCD isomeric compounds. The light tetraquark spectra ( only) with
ring-like and diquark-antidiquark structures are calculated in the flux tube
model. The results show that many experimental states have the masses close to
the calculated values if they are taken as tetraquark states. The isotensor
states with and are studied and predicted that
the masses are around 1500 MeV. The multi-body interaction plays a important
role to reduce the energy of the multiquark state.Comment: 10 pages, 4 figures, Some statements are change
An efficient system for the production of the medicinally important plant: Asparagus cochinchinensis (Lour.) Merr.
An in vitro cultivation protocol was developed for Asparagus cochinchinensis a species threatened by over collection due to its importance as a medicinal plant in China. Adventitious shoot induction was most successful by using hypocotyls as explants for propagation on Murashige and Skoog (Murashige et al., 1962) medium supplemented with 4.5 μM N6-benzylaminopurine (BA) only as well as with 3.0 μM α- naphthalene acetic acid (NAA) and 4.5 μM BA. For continuous subculture, indole-3-acetic acid (IAA) and BA (μM) at a ratio of 3.0:4.5 or 3.0:9.0 had the best regeneration potential producing approximately four plantlets per nodal explants. Plantlets had 4 – 5 nodes that could be utilized for the following subculture phase to induce axillary shoots. The plantlets were placed on ½-strength MS medium, indole-3-butyric acid (IBA) was included in the media at a concentration of 2.5 or 5.0 M. This propagation regime has the capacity for producing 1000 – 2000 plants from one shoot after 3 months long subculture cycles, making it highly attractive for implementation as an in vitro conservation strategy. The micropropagated plants were easily acclimatized (80%) within a month after rooting in vitro and being planted ex vitro in a sand : soil : peat moss : vermiculite (1:2:1:1; v/v/v/v) mixture.Key words: Medicinal herbs, Asparagus cochinchinensis (Lour.) Merr., micropropagation
The effect of different baryons impurities
We demonstrate the different effect of different baryons impurities on the
static properties of nuclei within the framework of the relativistic mean-field
model. Systematic calculations show that and has the
same attracting role as hyperon does in lighter hypernuclei.
and hyperon has the attracting role only for the protons
distribution, and has a repulsive role for the neutrons distribution. On the
contrary, and hyperon attracts surrounding neutrons and
reveals a repulsive force to the protons. We find that the different effect of
different baryons impurities on the nuclear core is due to the different third
component of their isospin.Comment: 9 page
The Online Data Quality Monitoring System at BESIII
The online Data Quality Monitoring (DQM) plays an important role in the data
taking process of HEP experiments. BESIII DQM samples data from online data
flow, reconstructs them with offline reconstruction software, and automatically
analyzes the reconstructed data with user-defined algorithms. The DQM software
is a scalable distributed system. The monitored results are gathered and
displayed in various formats, which provides the shifter with current run
information that can be used to find problems early. This paper gives an
overview of DQM system at BESIII.Comment: Already submit to Chinese Physics
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