244 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

    Novel ATP13A2 (PARK9) homozygous mutation in a family with marked phenotype variability

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    Mutations in the ATP13A2 (PARK9) and FBXO7 (PARK15) genes are linked to different forms of autosomal recessive juvenile-onset neurodegenerative diseases with overlapping phenotypes, including levodopa-responsive parkinsonism, pyramidal disturbances, cognitive decline, and supranuclear gaze disturbance. However, the associated genotypes and phenotypes are poorly characterized due to the small number of patients described. Here, we report clinical, instrumental, and genetic findings in an Italian family with novel PARK9 and PARK15 mutations. The proband developed a severe progressive phenotype including juvenile-onset parkinsonism, pyramidal disturbances, cognitive decline, and oculomotor abnormalities. On the contrary, his brother only shows mild abnormalities (pyramidal, cognitive, and oculomotor) on the neurological examination at the age of 31 years. These two brothers both carry a novel homozygous PARK9 missense (p.G877R) and a novel heterozygous PARK15 mutation (p.R481C). The PARK9 mutation replaces a crucial residue for the ATPase activity, and is therefore most likely a loss-of-function mutation and disease-causing in homozygous state. The pathogenic significance of the PARK15 single heterozygous mutation remains unclear. In both sibs, DaTSCAN single photon emission computed tomography showed marked nigrostriatal dopaminergic defects, and transcranial magnetic stimulation detected prolonged central motor conduction time. MRI, including T2*-weighted imaging, detected no evidence of brain iron accumulation. This family, the third reported with homozygous PARK9 mutations and the first with mutations in two genes for atypical juvenile parkinsonism, illustrates that PARK9-linked disease might display wide intra-familial clinical variability and milder phenotypes, suggesting the existence of strong, still unknown, modifiers

    Cancer risk from gaseous carbonyl compounds in indoor environment generated from household coal combustion in Xuanwei, China

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    Airborne carbonyls were characterized from emitted indoor coal combustion. Samples were collected in Xuanwei (Yunnan Province), a region in China with a high rate of lung cancer. Eleven of 19 types of samples (58%) demonstrated formaldehyde concentrations higher than the World Health Organization exposure limit (a 30-min average of 100 μg m−3). Different positive significant correlations between glyoxal/methylglyoxal and formaldehyde/acetaldehyde concentrations were observed, suggesting possible different characteristics in emissions between two pairs of carbonyl compounds. A sample in the highest inhalation risk shows 29.2 times higher risk than the lowest sample, suggesting different coal sampling locations could contribute to the variation of inhalation risk. Inhabitants in Xuanwei also tend to spend more time cooking and more days per year indoors than the national average. The calculated cancer risk ranged from 2.2–63 × 10−5, which shows 13 types of samples at high-risk level. Cumulative effect in combination with different carbonyls could have contributed to the additive actual inhalation cancer risk. There is a need to explicitly address the health effects of environmentally relevant doses, considering life-long exposure in indoor dwellings

    Prevalence and risk factors for esophageal squamous cell cancer and precursor lesions in Anyang, China: a population-based endoscopic survey

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    BACKGROUND: The etiology of esophageal squamous cell cancer (ESCC) in high prevalence regions of China remains unclear. METHODS: Endoscopic biopsies were conducted among 7381 inhabitants aged from 25 to 65 of Anyang, China. RESULTS: In this study, 2.57, 0.20 and 0.16% of the participants had mild, moderate and severe squamous dysplasia, respectively; 0.19 and 0.08% showed squamous carcinoma in situ and invasive ESCC. Using deep well (depth &gt;100 meters) as water source (odds ratio = 0.72, 95% confidence interval: 0.54-0.96) was negatively associated with ESCC and its precursors, whereas tobacco and alcohol use were not significantly associated with ESCC. CONCLUSIONS: Water source and other factors in this region need further evaluation by longitudinal studies. British Journal of Cancer (2010) 103, 1085-1088. doi:10.1038/sj.bjc.6605843 www.bjcancer.com Published online 10 August 2010 (C) 2010 Cancer Research UKOncologySCI(E)PubMed19ARTICLE71085-108810

    Functions of Some Capsular Polysaccharide Biosynthetic Genes in Klebsiella pneumoniae NTUH K-2044

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    The growing number of Klebsiella pneumoniae infections, commonly acquired in hospitals, has drawn great concern. It has been shown that the K1 and K2 capsular serotypes are the most detrimental strains, particularly to those with diabetes. The K1 cps (capsular polysaccharide) locus in the NTUH-2044 strain of the pyogenic liver abscess (PLA) K. pneumoniae has been identified recently, but little is known about the functions of the genes therein. Here we report characterization of a group of cps genes and their roles in the pathogenesis of K1 K. pneumoniae. By sequential gene deletion, the cps gene cluster was first re-delimited between genes galF and ugd, which serve as up- and down-stream ends, respectively. Eight gene products were characterized in vitro and in vivo to be involved in the syntheses of UDP-glucose, UDP-glucuronic acid and GDP-fucose building units. Twelve genes were identified as virulence factors based on the observation that their deletion mutants became avirulent or lost K1 antigenicity. Furthermore, deletion of kp3706, kp3709 or kp3712 (ΔwcaI, ΔwcaG or Δatf, respectively), which are all involved in fucose biosynthesis, led to a broad range of transcriptional suppression for 52 upstream genes. The genes suppressed include those coding for unknown regulatory membrane proteins and six multidrug efflux system proteins, as well as proteins required for the K1 CPS biosynthesis. In support of the suppression of multidrug efflux genes, we showed that these three mutants became more sensitive to antibiotics. Taken together, the results suggest that kp3706, kp3709 or kp3712 genes are strongly related to the pathogenesis of K. pneumoniae K1

    Branching fraction measurements of χc0 and χc2 to π0π0 and ηη

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    Using a sample of 1.06×108 ψ ′ decays collected by the BESIII detector, χc0 and χc2 decays into π0π0 and ηη are studied. The branching fraction results are Br(χc0→π 0π0)=(3.23±0.03±0.23±0.14)×10 -3, Br(χc2→π0π0)=(8.8±0.2±0.6±0.4)×10 -4, Br(χc0→ηη)=(3.44±0.10±0. 24±0.2)×10 -3, and Br(χc2→ηη)=(6. 5±0.4±0.5±0.3)×10 -4, where the uncertainties are statistical, systematic due to this measurement, and systematic due to the branching fractions of ψ ′→ γχcJ. The results provide information on the decay mechanism of χc states into pseudoscalars. © 2010 The 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

    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

    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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