105 research outputs found
Energy Level Statistics of the U(5) and O(6) Symmetries in the Interacting Boson Model
We study the energy level statistics of the states in U(5) and O(6) dynamical
symmetries of the interacting boson model and the high spin states with
backbending in U(5) symmetry. In the calculations, the degeneracy resulting
from the additional quantum number is eliminated manually. The calculated
results indicate that the finite boson number effect is prominent. When
has a value close to a realistic one, increasing the interaction strength of
subgroup O(5) makes the statistics vary from Poisson-type to GOE-type and
further recover to Poisson-type. However, in the case of , they
all tend to be Poisson-type. The fluctuation property of the energy levels with
backbending in high spin states in U(5) symmetry involves a signal of shape
phase transition between spherical vibration and axial rotation.Comment: 38 pages, 13 figure
Genotype-Phenotype Correlation in NF1: Evidence for a More Severe Phenotype Associated with Missense Mutations Affecting NF1 Codons 844–848
Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000–3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons—Leu844, Cys845, Ala846, Leu847, and Gly848—located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844–848 exists and will be valuable in the management and genetic counseling of a significant number of individuals
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Auroral Processes at the Giant Planets: Energy Deposition, Emission Mechanisms, Morphology and Spectra
Visual Outcome and Prognostic Factors after Vitrectomy for Posterior Segment Foreign Bodies
Treatment of subfoveal pigment epithelial detachments with distant extrafoveal choroidal neovascular membranes.
Controlled trial of laser photocoagulation of pigment epithelial detachments in the elderly: 4 year review.
Is thioridazine retinopathy progressive? Relationship of pigmentary changes to visual function.
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