6,178 research outputs found
Variants of the low oxygen sensors EGLN1 and HIF-1AN associated with acute mountain sickness.
Two low oxygen sensors, Egl nine homolog 1 (EGLN1) and hypoxia-inducible factor 1-α inhibitor (HIF-1AN), play pivotal roles in the regulation of HIF-1α, and high altitude adaption may be involved in the pathology of acute mountain sickness (AMS). Here, we aimed to analyze single nucleotide polymorphisms (SNPs) in the untranslated regions of the EGLN1 and HIF-1AN genes and SNPs chosen from a genome-wide adaptation study of the Han Chinese population. To assess the association between EGLN1 and HIF-1AN SNPs and AMS in a Han Chinese population, a case-control study was performed including 190 patients and 190 controls. In total, thirteen SNPs were genotyped using the MassARRAY® MALDI-TOF system. Multiple genetic models were tested; The Akaike's information criterion (AIC) and Bayesian information criterion (BIC) values indicated that the dominant model may serve as the best-fit model for rs12406290 and rs2153364 of significant difference. However, these data were not significant after Bonferroni correction. No significant association was noted between AMS and rs12757362, rs1339894, rs1361384, rs2009873, rs2739513 or rs2486729 before and after Bonferroni correction. Further haplotype analyses indicated the presence of two blocks in EGLN1; one block consists of rs12406290-rs2153364, located upstream of the EGLN1 gene. Carriers of the "GG" haplotype of rs12406290-rs2153364 exhibited an increased risk of AMS after adjustments for age and smoking status. However, no significant association was observed among HIF-1AN 3'-untranslated region (3'-UTR) polymorphisms, haplotype and AMS. Our study indicates that variants in the EGLN1 5'-UTR influence the susceptibility to AMS in a Han Chinese population
Study of the weak annihilation contributions in charmless decays
In this paper, in order to probe the spectator-scattering and weak
annihilation contributions in charmless (where stands for a
light vector meson) decays, we perform the -analyses for the end-point
parameters within the QCD factorization framework, under the constraints from
the measured , , and
decays. The fitted results indicate that the end-point
parameters in the factorizable and nonfactorizable annihilation topologies are
non-universal, which is also favored by the charmless and (where
stands for a light pseudo-scalar meson) decays observed in the previous
work. Moreover, the abnormal polarization fractions measured by the LHCb
collaboration can be reconciled through the weak annihilation corrections.
However, the branching ratio of decay exhibits a
tension between the data and theoretical result, which dominates the
contributions to in the fits. Using the fitted end-point
parameters, we update the theoretical results for the charmless
decays, which will be further tested by the LHCb and Belle-II experiments in
the near future.Comment: 31 pages, 4 figures, 6 table
Elastic parton scattering and non-statistical event-by-event mean-pt fluctuations in Au + Au collisions at RHIC
Non-statistical event-by-event mean-pt fluctuations in Au + Au collisions at
sqrt(s_NN) = 130 and 200 GeV are analyzed in AMPT with string-melting, and the
results are compared with STAR data. The analysis suggests that in-medium
elastic parton scattering may contribute greatly to the mean-p_t fluctuations
in relativistic heavy-ion collisions. Furthermore, it is demonstrated that
non-statistical event-by-event mean-pt fluctuations can be used to probe the
initial partonic dynamics in these collisions. The comparison shows that with
an in-medium elastic parton scattering cross section sigma_p=10 mb, AMPT with
string-melting can well reproduce sqrt(s_NN) = 130 GeV data on the centrality
dependence of non-statistical event-by-event mean-pt fluctuations. The
comparison also shows that the fluctuation data for sqrt(s_NN) = 200 GeV Au +
Au collisions can be well reproduced with sigma_p between 6 and 10 mb.Comment: 6 pages, 3 figure
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