We present one of the first Shanghai Tian Ma Radio Telescope (TMRT) K Band observations towards a sample of 26 infrared dark clouds (IRDCs).We observed the (1,1),(2,2),(3,3),and (4,4) transitions of NH_(3) together wi...
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We present one of the first Shanghai Tian Ma Radio Telescope (TMRT) K Band observations towards a sample of 26 infrared dark clouds (IRDCs).We observed the (1,1),(2,2),(3,3),and (4,4) transitions of NH_(3) together with CCS (2_(1)–>1_(0)) and HC_(3)NJ=2-1,*** survey dramatically increases the existing CCS-detected IRDC sample from 8 to 23,enabling a better statistical study of the ratios of carbon-chain molecules (CCM) to N-bearing molecules in *** the newly developed hyperfine group ratio (HFGR) method of fitting NH_(3) inversion lines,we found the gas temperature to be between 10 and18 *** column density ratios of CCS to NH_(3) for most of the IRDCs are less than 10^(-2),distinguishing IRDCs from low-mass star-forming *** carried out chemical evolution simulations based on a three-phase chemical model *** measurements of the column density ratios between CCM and NH_(3) are consistent with chemical evolutionary ages of 10^(5) yr in the *** of the data and chemical models suggest that CCS,HC_(3)N,and NH_(3) are sensitive to the chemical evolutionary stages of the sources.
Much of the genetic predisposition to polyposis,and particularly to serrated polyposis(SP),remains *** germline pathogenic variants in RNF43,a tumor suppressor that exerts negative feedback in the Wnt/β-catenin signa...
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Much of the genetic predisposition to polyposis,and particularly to serrated polyposis(SP),remains *** germline pathogenic variants in RNF43,a tumor suppressor that exerts negative feedback in the Wnt/β-catenin signaling pathway,have been causally linked to some SP cases(disease associated with increased risk of colorectal cancer(CRC).^(1) Most known hereditary CRC and polyposis genes affect DNA repair,BMP/TGF-β,or Wnt signaling,being the latter associated with adenomatous and serrated polyposis phenotypes.2 Based on this observation,we evaluated the presence and role of germline variants in those pathways in unsolved polyposis patients.
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