232 research outputs found
as a molecule from the pole counting rule
A comprehensive study on the nature of the resonant structure is
carried out in this work. By constructing the pertinent effective Lagrangians
and considering the important final-state-interaction effects, we first give a
unified description to all the relevant experimental data available, including
the and invariant mass distributions from the process, the distribution from and
also the spectrum in the process.
After fitting the unknown parameters to the previous data, we search the pole
in the complex energy plane and find only one pole in the nearby energy region
in different Riemann sheets. Therefore we conclude that is of
molecular nature, according to the pole counting rule
method~[Nucl.~Phys.~A543, 632 (1992); Phys.~Rev.~D 35,~1633 (1987)]. We
emphasize that the conclusion based upon the pole counting method is not
trivial, since both the contact interactions and the explicit
exchanges are introduced in our analyses and they lead to the same
conclusion.Comment: 21 pages, 9 figures. To match the published version in PRD.
Additional discussion on the spectral density function is include
On leptonic width of
New measurements on cross sections in ,
, , ,
and channels have been carried out by BESIII, Belle and BABAR
collaborations, and also in the channel. We perform extensive
numerical analyses by combining all these data available, together with those
in and channels. Though the latter show no evident
peak around GeV, the missing is explained as that it
is concealed by the interference effects of the well established charmonia
, and . Our analyses reveal that the
leptonic decay width of ranges from eV to keV, and
hence may be explained in the conventional quark model picture. That is, the
may well be interpreted as a mixture of and states.Comment: two small mistakes are fixed, figures redrawn, major physical outputs
remain unchanged. Version published in EPJ
Effects of Mo on the Microstructure and Hydrogen Sorption Properties of Ti-Mo Getters
AbstractThe effects of Mo on the microstructure evolution, porosity and hydrogen sorption properties of Ti-Mo getters are investigated in this work. The results show that the addition of Mo prolongs the densification process of Ti-Mo getters and results in a significant amount of sintered pores. With the Mo content increasing, the porosity of getters firstly increases reaching the maximum value as it attains about 7.5wt.%, and then drops. At the room temperature, the hydrogen sorption property of getters increases progressively with the Mo content increasing, but the tendency is not very clear before its content lies below 2.5wt.%. When the Mo content achieves about 7.5wt.%, the hydrogen sorption property proves to be the best. The discussion is made about the above mentioned phenomena inclusive of hydrogen sorption properties of getters under different activation conditions (from 500–750 °C)
Upregulation of microRNA-25 associates with prognosis in hepatocellular carcinoma
BACKGROUND: Accumulating evidence has shown that up-regulation of microRNA-25(miR-25) is associated with the prognosis of several types of human malignant solid tumors. However, whether miR-25 expression has influence on the prognosis of hepatocellular carcinoma (HCC) is still unknown. METHODS: The differentially expressed amount of the miR-25 was validated in triplicate by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Survival rate was analyzed by log-rank test, and survival curves were plotted according to Kaplan–Meier. Multivariate analysis of the prognostic factors was performed with Cox regression model. RESULTS: The expression of miR-25 was significantly upregulated in HCC tissues when compared with adjacent normal tissues (p<0.0001). Patients who had high miR-25 expression had a shorter overall survival than patients who had low miR-25 expression (median overall survival, 31.0 months versus 42.9 months, p=0.0192). The multivariate Cox regression analysis indicated that miR-25 expression (HR=2.179; p=0.001), TNM stage (HR=1.782; p=0.014), and vein invasion (HR=1.624; p=0.020) were independent prognostic factors for overall survival. CONCLUSION: Our data suggests that the overexpression of miR-25 in HCC tissues is of predictive value on poor prognosis. VIRTUAL SLIDE: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/198961842111430
Transforming Multidisciplinary Customer Requirements to Product Design Specifications
With the increasing of complexity of complex mechatronic products, it is necessary to involve multidisciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes difficult to be applied in a multidisciplinary team and project since team members with various disciplinary backgrounds may have different interpretations of the customers’ requirements. A new synthesized multidisciplinary customer requirements modeling method is provided for obtaining and describing the common understanding of customer requirements (CRs) and more importantly transferring them into a detailed and accurate product design specifications (PDS) to interact with different team members effectively. A case study of designing a high speed train verifies the rationality and feasibility of the proposed multidisciplinary requirement modeling method for complex mechatronic product development. This proposed research offersthe instruction to realize the customer-driven personalized customization of complex mechatronic product
Investigating a Global Collapsing Hub-Filament Cloud G326.611+0.811
We present the dynamics study toward the G326.611+0.811 (G326)
hub-filament-system (HFS) cloud using the new APEX observations of both
CO and CO (J = 2-1). The G326 HFS cloud constitutes a central hub
and at least four hub-composing filaments that are divided into a major branch
of filaments (F1, and F2) and a side branch (F3-F5). The cloud holds ongoing
high-mass star formation as characterised by three massive dense clumps (i.e.,
370-1100 and 0.14-0.16 g cm for C1-C3) with the high
clump-averaged mass infalling rates ( yr) within
in the major filament branch, and the associated point sources bright at 70
m typical of young protostars. Along the five filaments, the velocity
gradients are found in both CO and CO (J = 2-1) emission,
suggesting that the filament-aligned gravitational collapse toward the central
hub (i.e., C2) is being at work for high-mass star formation therein. Moreover,
a periodic velocity oscillation along the major filament branch is revealed in
both CO and CO (J = 2-1) emission with a characteristic
wavelength of 3.5 pc and an amplitude of 0.31-0.38 km s. We
suggest that this pattern of velocity oscillation in G326 could arise from the
clump-forming gas motions induced by gravitational instability. Taking into
account the prevalent velocity gradients, the fragmentation of the major branch
of filaments, and the ongoing collapse of the three massive dense clumps, it is
indicative that G326 is a HFS undergoing global collapse.Comment: 21 pages, 13 figures, 2 tables, Accepted for publication in Ap
A possible 250-second X-ray quasi-periodicity in the fast blue optical transient AT2018cow
The fast blue optical transients (FBOTs) are a new population of
extragalactic transients of unclear physical origin. A variety of mechanisms
have been proposed including failed supernova explosion, shock interaction with
a dense medium, young magnetar, accretion onto a compact object, and stellar
tidal disruption event, but none is conclusive. Here we report the discovery of
a possible X-ray quasi-periodicity signal with a period of 250 second (at
a significance level of 99.76%) in the brightest FBOT AT2018cow through the
analysis of XMM-Newton/PN data. The signal is independently detected at the
same frequency in the average power density spectrum from data taken from the
Swift telescope, with observations covering from 6 to 37 days after the optical
discovery, though the significance level is lower (94.26%). This suggests that
the QPO frequency may be stable over at least 1.1 10 cycles.
Assuming the 250 second QPO to be a scaled-down analogue of that
typically seen in stellar mass black holes, a black hole mass of
solar masses could be inferred. The overall X-ray
luminosity evolution could be modeled with the stellar tidal disruption by a
black hole of solar masses, providing a viable mechanism to produce
AT2018cow. Our findings suggest that other bright FBOTs may also harbor
intermediate-mass black holes.Comment: 18 pages, 10 figures. Accepted for publication in Research in
Astronomy and Astrophysic
A simulation study on the measurement of D0-D0bar mixing parameter y at BES-III
We established a method on measuring the \dzdzb mixing parameter for
BESIII experiment at the BEPCII collider. In this method, the doubly
tagged events, with one decays to
CP-eigenstates and the other decays semileptonically, are used to
reconstruct the signals. Since this analysis requires good separation,
a likelihood approach, which combines the , time of flight and the
electromagnetic shower detectors information, is used for particle
identification. We estimate the sensitivity of the measurement of to be
0.007 based on a fully simulated MC sample.Comment: 6 pages, 7 figure
- …