941 research outputs found
What do -ray bursts look like?
There have been great and rapid progresses in the field of -ray
bursts (denoted as GRBs) since BeppoSAX and other telescopes discovered their
afterglows in 1997. Here, we will first give a brief review on the
observational facts of GRBs and direct understanding from these facts, which
lead to the standard fireball model. The dynamical evolution of the fireball is
discussed, especially a generic model is proposed to describe the whole
dynamical evolution of GRB remnant from highly radiative to adiabatic, and from
ultra-relativistic to non-relativistic phase. Then, Various deviations from the
standard model are discussed to give new information about GRBs and their
environment. In order to relax the energy crisis, the beaming effects and their
possible observational evidences are also discussed in GRB's radiations.Comment: 10 pages, Latex. Invited talk at the Pacific Rim Conference on
Stellar Astrophysics, Hong Kong, China, Aug. 199
Review of multi-scale electromagnetic modeling
This paper reviews various methods to solve multiscale problems ranging from low-frequency methods to very high-frequency methods. ©2010 IEEE.published_or_final_versionThe 2010 International Conference on Electromagnetics in Advanced Applications (ICEAA), Sydney, N.S.W., 20-24 September 2010. In Proceedings of ICEAA'10, 2010, p. 641-64
Phase Separation and Magnetic Order in K-doped Iron Selenide Superconductor
Alkali-doped iron selenide is the latest member of high Tc superconductor
family, and its peculiar characters have immediately attracted extensive
attention. We prepared high-quality potassium-doped iron selenide (KxFe2-ySe2)
thin films by molecular beam epitaxy and unambiguously demonstrated the
existence of phase separation, which is currently under debate, in this
material using scanning tunneling microscopy and spectroscopy. The
stoichiometric superconducting phase KFe2Se2 contains no iron vacancies, while
the insulating phase has a \surd5\times\surd5 vacancy order. The iron vacancies
are shown always destructive to superconductivity in KFe2Se2. Our study on the
subgap bound states induced by the iron vacancies further reveals a
magnetically-related bipartite order in the superconducting phase. These
findings not only solve the existing controversies in the atomic and electronic
structures in KxFe2-ySe2, but also provide valuable information on
understanding the superconductivity and its interplay with magnetism in
iron-based superconductors
Inherent Dynamics of the Acid-Sensing Ion Channel 1 Correlates with the Gating Mechanism
A combination of computational and experimental approaches reveals the dynamics of ASIC1 gating, involving a deformation of the channel that triggers “twist-to-open” motions of the channel pore
Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay
The decay channel
is studied using a sample of events collected
by the BESIII experiment at BEPCII. A strong enhancement at threshold is
observed in the invariant mass spectrum. The enhancement can be fit
with an -wave Breit-Wigner resonance function with a resulting peak mass of
and a
narrow width that is at the 90% confidence level.
These results are consistent with published BESII results. These mass and width
values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics
International consensus on natural orifice specimen extraction surgery (NOSES) for colorectal cancer
In recent years, natural orifice specimen extraction surgery (NOSES) in the treatment of colorectal cancer has attracted widespread attention. The potential benefits of NOSES including reduction in postoperative pain and wound complications, less use of postoperative analgesic, faster recovery of bowel function, shorter length of hospital stay, better cosmetic and psychological effect have been described in colorectal surgery. Despite significant decrease in surgical trauma of NOSES have been observed, the potential pitfalls of this technique have been demonstrated. Particularly, several issues including bacteriological concerns, oncological outcomes and patient selection are raised with this new technique. Therefore, it is urgent and necessary to reach a consensus as an industry guideline to standardize the implementation of NOSES in colorectal surgery. After three rounds of discussion by all members of the International Alliance of NOSES, the consensus is finally completed, which is also of great significance to the long-term progress of NOSES worldwide.info:eu-repo/semantics/publishedVersio
A Missense Mutation in PPARD Causes a Major QTL Effect on Ear Size in Pigs
Chinese Erhualian is the most prolific pig breed in the world. The breed exhibits exceptionally large and floppy ears. To identify genes underlying this typical feature, we previously performed a genome scan in a large scale White Duroc × Erhualian cross and mapped a major QTL for ear size to a 2-cM region on chromosome 7. We herein performed an identical-by-descent analysis that defined the QTL within a 750-kb region. Historically, the large-ear feature has been selected for the ancient sacrificial culture in Erhualian pigs. By using a selective sweep analysis, we then refined the critical region to a 630-kb interval containing 9 annotated genes. Four of the 9 genes are expressed in ear tissues of piglets. Of the 4 genes, PPARD stood out as the strongest candidate gene for its established role in skin homeostasis, cartilage development, and fat metabolism. No differential expression of PPARD was found in ear tissues at different growth stages between large-eared Erhualian and small-eared Duroc pigs. We further screened coding sequence variants in the PPARD gene and identified only one missense mutation (G32E) in a conserved functionally important domain. The protein-altering mutation showed perfect concordance (100%) with the QTL genotypes of all 19 founder animals segregating in the White Duroc × Erhualian cross and occurred at high frequencies exclusively in Chinese large-eared breeds. Moreover, the mutation is of functional significance; it mediates down-regulation of β-catenin and its target gene expression that is crucial for fat deposition in skin. Furthermore, the mutation was significantly associated with ear size across the experimental cross and diverse outbred populations. A worldwide survey of haplotype diversity revealed that the mutation event is of Chinese origin, likely after domestication. Taken together, we provide evidence that PPARD G32E is the variation underlying this major QTL
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