258 research outputs found

    Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

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    The decay channel ψπ+πJ/ψ(J/ψγppˉ)\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) is studied using a sample of 1.06×1081.06\times 10^8 ψ\psi^\prime events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the ppˉp\bar{p} invariant mass spectrum. The enhancement can be fit with an SS-wave Breit-Wigner resonance function with a resulting peak mass of M=186113+6(stat)26+7(syst)MeV/c2M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2 and a narrow width that is Γ<38MeV/c2\Gamma<38 {\rm MeV/}c^2 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

    Effects of Thioglycolic Acid on Parthenogenetic Activation of Xenopus Oocytes

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    BACKGROUND: Existing in Permanent-wave solutions (PWS), thioglycolic acid (TGA) is widely used in hairdressing industry for its contribution to hair styling. However, the toxicity of TGA, especially its reproductive toxicity, gradually calls the attention of more and more researchers. METHOD: In this work, xenopus oocytes were pretreated with different concentration of TGA, and then activated by calcium ionophore A23187. During culture, the oocytes activation rates were taken note at different time after adding calcium ionophore A23187. At the end of the culture period, the nuclear status was detected under confocal microscope. In addition, some other samples were collected for Western-Blotting analysis. RESULT: TGA significantly inhibited the oocytes activation rate and pronuclear formation. It may be resulted from the inhibition of the degradation of p-ERK1, Mos and CyclinB2. CONCLUSION: TGA inhibits in vitro parthenogenetic activation of xenopus oocytes with inhibited the degradation of proteins involved in mitogenic-activated protein kinase (MAPK) and maturation-promoting factor (MPF) pathways

    Genome Sequence and Transcriptome Analysis of the Radioresistant Bacterium Deinococcus gobiensis: Insights into the Extreme Environmental Adaptations

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    The desert is an excellent model for studying evolution under extreme environments. We present here the complete genome and ultraviolet (UV) radiation-induced transcriptome of Deinococcus gobiensis I-0, which was isolated from the cold Gobi desert and shows higher tolerance to gamma radiation and UV light than all other known microorganisms. Nearly half of the genes in the genome encode proteins of unknown function, suggesting that the extreme resistance phenotype may be attributed to unknown genes and pathways. D. gobiensis also contains a surprisingly large number of horizontally acquired genes and predicted mobile elements of different classes, which is indicative of adaptation to extreme environments through genomic plasticity. High-resolution RNA-Seq transcriptome analyses indicated that 30 regulatory proteins, including several well-known regulators and uncharacterized protein kinases, and 13 noncoding RNAs were induced immediately after UV irradiation. Particularly interesting is the UV irradiation induction of the phrB and recB genes involved in photoreactivation and recombinational repair, respectively. These proteins likely include key players in the immediate global transcriptional response to UV irradiation. Our results help to explain the exceptional ability of D. gobiensis to withstand environmental extremes of the Gobi desert, and highlight the metabolic features of this organism that have biotechnological potential

    Mutations in the Spliceosome Component CWC27 Cause Retinal Degeneration with or without Additional Developmental Anomalies

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    Pre-mRNA splicing factors play a fundamental role in regulating transcript diversity both temporally and spatially. Genetic defects in several spliceosome components have been linked to a set of non-overlapping spliceosomopathy phenotypes in humans, among which skeletal developmental defects and non-syndromic retinitis pigmentosa (RP) are frequent findings. Here we report that defects in spliceosome-associated protein CWC27 are associated with a spectrum of disease phenotypes ranging from isolated RP to severe syndromic forms. By whole-exome sequencing, recessive protein-truncating mutations in CWC27 were found in seven unrelated families that show a range of clinical phenotypes, including retinal degeneration, brachydactyly, craniofacial abnormalities, short stature, and neurological defects. Remarkably, variable expressivity of the human phenotype can be recapitulated in Cwc27 mutant mouse models, with significant embryonic lethality and severe phenotypes in the complete knockout mice while mice with a partial loss-of-function allele mimic the isolated retinal degeneration phenotype. Our study describes a retinal dystrophy-related phenotype spectrum as well as its genetic etiology and highlights the complexity of the spliceosomal gene network

    Measurement of the matrix element for the decay η′→ηπ +π -

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    The Dalitz plot of η⊃′→ηπ⊃+π⊃- decay is studied using (225.2±2.8)×106 J/ψ events collected with the BESIII detector at the BEPCII e⊃+e⊃- collider. With the largest sample of η⊃′ decays to date, the parameters of the Dalitz plot are determined in a generalized and a linear representation. Also, the branching fraction of J/ψ→γη⊃′ is determined to be (4.84±0.03±0.24)×10⊃-3, where the first error is statistical and the second systematic. © 2011 American Physical Society.published_or_final_versio

    First observation of the decays χcJ→π0π0π0π0

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    We present a study of the P-wave spin-triplet charmonium χ cJ decays (J=0, 1, 2) into π0π0π0π0. The analysis is based on 106×106 ψ⊃′ decays recorded with the BESIII detector at the BEPCII electron positron collider. The decay into the π0π0π0π0 hadronic final state is observed for the first time. We measure the branching fractions B(χ c0→π0π0π0π0)=(3.34±0. 06±0.44)×10⊃-3, B(χ c1→π0π0π0π0) =(0.57±0.03±0.08)×10⊃-3, and B(χ c2→π0π0π0π0)=(1.21±0.05±0.16) ×10⊃-3, where the uncertainties are statistical and systematical, respectively. © 2011 American Physical Society.published_or_final_versio

    Higher-order multipole amplitude measurement in ψ ′→γχ c2

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    Using 106×106 ψ ′ events collected with the BESIII detector at the BEPCII storage ring, the higher-order multipole amplitudes in the radiative transition ψ ′→γχ c2→γπ +π -/γK +K - are measured. A fit to the χ c2 production and decay angular distributions yields M2=0.046±0. 010±0.013 and E3=0.015±0.008±0.018, where the first errors are statistical and the second systematic. Here M2 denotes the normalized magnetic quadrupole amplitude and E3 the normalized electric octupole amplitude. This measurement shows evidence for the existence of the M2 signal with 4.4σ statistical significance and is consistent with the charm quark having no anomalous magnetic moment. © 2011 American Physical Society.published_or_final_versio
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