762 research outputs found
Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC
Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe
Expression of Iodotyrosine Deiodinase in Thyroid and Other Organs in Iodine-Deficient and Iodine-Excess Rats
ÎČ-Nitroso-o-Quinone Methides: Potent Intermediates in Organic Chemistry and Biology : The impact of the NO group on their Structure and Reactivity Profile: a Theoretical Insight
The structure and reactivity profile of prototype o-quinone methides 1, 2 and their Ă-nitroso analogues 6-9 have been investigated by means of DFT and MP2 calculations. These highly reactive unstable species are generated by oxidative dearomatization of their precursor oximes. The destabilization of their structure is more pronounced in the Ă-nitroso congeners 7-9. There is only a weak Ï conjugation across the nitrosoalkene arm. The latter gives rise to E and Z conformations and causes some distortion on the ring -frame while the Ï-frame is weakly perturbed. The Z conformation is the most stable in all structures. Their geometry is also affected by the o-quinone ring and the 1,2-(7 and 8) and 2,3-(9) isomer pattern. The stability of these conformations is rationalized in terms of ortho- or peri- ring formations. The impact of their geometry profile on their reactivity pattern has been studied by means of reactivity descriptors such as Fukui function f(r), chemical potential and hardness, HOMO and LUMO energies and their separation (HOMO-LUMO gap) as well as aromaticity indices such as HOMA and out-of-plane deformability. All descriptors consistently demonstrate that the reactivity is dominated by an intramolecular ortho or peri-cyclization mode to fused 1,2-oxazoles or 1,2-oxazines, respectively. Intermolecular primary reactions can occur at the quinone alkene bond or that of the nitrosoalkene arm.Peer reviewe
Multiplicity dependence of light (anti-)nuclei production in pâPb collisions at sNN=5.02 TeV
The measurement of the deuteron and anti-deuteron production in the rapidity range â1 < y < 0 as a function of transverse momentum and event multiplicity in pâPb collisions at âsNN = 5.02 TeV is presented. (Anti-)deuterons are identified via their specific energy loss dE/dx and via their time-of- flight. Their production in pâPb collisions is compared to pp and PbâPb collisions and is discussed within the context of thermal and coalescence models. The ratio of integrated yields of deuterons to protons (d/p) shows a significant increase as a function of the charged-particle multiplicity of the event starting from values similar to those observed in pp collisions at low multiplicities and approaching those observed in PbâPb collisions at high multiplicities. The mean transverse particle momenta are extracted from the deuteron spectra and the values are similar to those obtained for p and particles. Thus, deuteron spectra do not follow mass ordering. This behaviour is in contrast to the trend observed for non-composite particles in pâPb collisions. In addition, the production of the rare 3He and 3He nuclei has been studied. The spectrum corresponding to all non-single diffractive p-Pb collisions is obtained in the rapidity window â1 < y < 0 and the pT-integrated yield dN/dy is extracted. It is found that the yields of protons, deuterons, and 3He, normalised by the spin degeneracy factor, follow an exponential decrease with mass number
Genomic Profiling of Childhood Tumor Patient-Derived Xenograft Models to Enable Rational Clinical Trial Design
Accelerating cures for children with cancer remains an immediate challenge as a result of extensive oncogenic heterogeneity between and within histologies, distinct molecular mechanisms evolving between diagnosis and relapsed disease, and limited therapeutic options. To systematically prioritize and rationally test novel agents in preclinical murine models, researchers within the Pediatric Preclinical Testing Consortium are continuously developing patient-derived xenografts (PDXs)âmany of which are refractory to current standard-of-care treatmentsâfrom high-risk childhood cancers. Here, we genomically characterize 261 PDX models from 37 unique pediatric cancers; demonstrate faithful recapitulation of histologies and subtypes; and refine our understanding of relapsed disease. In addition, we use expression signatures to classify tumors for TP53 and NF1 pathway inactivation. We anticipate that these data will serve as a resource for pediatric oncology drug development and will guide rational clinical trial design for children with cancer
Increased Expression of Calcium/Calmodulin-Dependent Protein Kinase Type II Subunit Delta after Rat Traumatic Brain Injury
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