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The TAPIRO reactor is an experimental facility that may provide important information on the quality of nuclear data used for reactor physics evaluations. In particular, the presence of a large quantity of copper in the reflector, allows to qualify the adequateness of the existing data for this material in various libraries. In this work, the Serpent code is used to simulate reaction rates that were measured in an experimental campaign carried out in the past. The comparison quantifies the differences in the results obtained using JEFF-3.1.1 and ENDF/B-VIII libraries.

International audience; Thecurrenttrendsofcomputationalanalysesofnuclearreactordynamicsinnormal, incidentand accident scenarios are characterised by the desire to model the relevant physical phenomena with increasing accuracy and to remain within practical limits of computational time. Considering the implications on the modelling of neutronics, it is understood that phase-space-dependent neutron kinetics is necessary in order to achieve the requirements on accuracy. However, the solution of theneutronanddelayedneutronprecursorbalanceequationsbymeansofthetraditionalapproach of direct numerical integration contributes significantly to the computational burden, which is a consequence of the large number of unknowns and the time-stiffness of the system of balance equations.

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Contains fulltext : 110038.pdf (Publisher’s version ) (Closed access) Potocki-Shaffer syndrome (PSS) is a contiguous gene disorder due to the interstitial deletion of band p11.2 of chromosome 11 and is characterized by multiple exostoses, parietal foramina, intellectual disability (ID), and craniofacial anomalies (CFAs). Despite the identification of individual genes responsible for multiple exostoses and parietal foramina in PSS, the identity of the gene(s) associated with the ID and CFA phenotypes has remained elusive. Through characterization of independent subjects with balanced translocations and supportive comparative deletion mapping of PSS subjects, we have uncovered evidence that the ID and CFA phenotypes are both caused by haploinsufficiency of a single gene, PHF21A, at 11p11.2. PHF21A encodes a plant homeodomain finger protein whose murine and zebrafish orthologs are both expressed in a manner consistent with a function in neurofacial and craniofacial development, and suppression of the latter led to both craniofacial abnormalities and neuronal apoptosis. Along with lysine-specific demethylase 1 (LSD1), PHF21A, also known as BHC80, is a component of the BRAF-histone deacetylase complex that represses target-gene transcription. In lymphoblastoid cell lines from two translocation subjects in whom PHF21A was directly disrupted by the respective breakpoints, we observed derepression of the neuronal gene SCN3A and reduced LSD1 occupancy at the SCN3A promoter, supporting a direct functional consequence of PHF21A haploinsufficiency on transcriptional regulation. Our finding that disruption of PHF21A by translocations in the PSS region is associated with ID adds to the growing list of ID-associated genes that emphasize the critical role of transcriptional regulation and chromatin remodeling in normal brain development and cognitive function.

Potocki-Shaffer syndrome is a rare contiguous gene deletion syndrome due to haploinsufficiency of the 11p11.2p12 region and is characterized by craniofacial abnormalities, developmental delay, intellectual disability, multiple exostoses, and biparietal foramina. In this study, six patients with the Potocki-Shaffer syndrome were identified and evaluated using a multidisciplinary protocol that included assessments by a geneticist, ophthalmologist, otolaryngologist, orthopedist, nephrologist, audiologist, and neuropsychologist. Diagnostic studies included skeletal survey, magnetic resonance imaging of the brain, renal ultrasound, complete blood count, comprehensive metabolic panel, thyroid studies, and urinalysis. Using array comparative genomic hybridization, we further characterized the deletion in five of these patients. The results of these evaluations were combined with a comprehensive review of reported cases. Our data highlight the characteristic facial features, biparietal foramina, moderate-to-severe developmental delay and intellectual disability, myopia and strabismus, and multiple exostoses seen with this disorder. We also identify for the first time an association of Potocki-Shaffer syndrome with sensorineural hearing loss and autistic behaviors. Finally, we provide recommendations for the health maintenance of patients with Potocki-Shaffer syndrome.

The mechanisms involved in the formation of subtelomeric rearrangements are now beginning to be elu- cidated. Breakpoint sequencing analysis of 1p36 rear- rangements has made important contributions to this line of inquiry. Despite the unique architecture of segmental duplications inherent to human subtelomeres, no common mechanism has been identiWed thus far and diVerent non- exclusive recombination-repair mechanisms seem to predominate. In order to gain further insights into the mechanisms of chromosome breakage, repair, and stabilization mediating subtelomeric rearrangements in humans, we investigated the constitutional rearrangements of 1p36. Cloning of the breakpoint junctions in a complex rear- rangement and three non-reciprocal translocations revealed similarities at the junctions, such as microhomology of up to three nucleotides, along with no signiWcant sequence iden- tity in close proximity to the breakpoint regions. All the breakpoints appeared to be unique and their occurrence was limited to non-repetitive, unique DNA sequences. Several recombination- or cleavage-associated motifs that may promote non-homologous recombination were observed in close proximity to the junctions. We conclude that NHEJ is likely the mechanism of DNA repair that generates these rearrangements. Additionally, two appar- ently pure terminal deletions were also investigated, and the reWnement of the breakpoint regions identiWed two dis- tinct genomic intervals »25-kb apart, each containing a series of 1p36 speciWc segmental duplications with 90-98% identity. Segmental duplications can serve as substrates for ectopic homologous recombination or stimulate geno- mic rearrangements.