23 research outputs found
Molecular and epidemiological studies of bladder exstrophy and epispadias complex
No full textBladder exstrophy and epispadias complex is a rare congenital genitourinary malformation involving a midline closure defect, leaving an open bladder on the lower abdominal wall.In Sweden, the prevalence is 3:100 000 live births and the male to female ratio is almost equal. It is regarded to result from a disruption during the normal embryogenesis of the urinary bladder. The recurrence risk of bladder exstrophy is around 1 in 70 siblings. Several reports on chromosome aberrations and twin studies support a genetic background, with the 22q11.2 microduplication being the only recurrent genetic finding so far.The studies in this thesis aimed to answer some questions that the parents of children born with malformations usually have. In particular, why did it occur, what is the recurrence risk, and what is the prognosis.The first study evaluated the candidate gene ISL1 in 125 Swedish individuals with this malformation using Sanger sequencing. The only novel, potentially pathogenic finding, a missense variant, was inherited from the healthy mother. Thus, we concluded that the role of the ISL1 gene in the pathogenesis of bladder exstrophy is uncommon in our Swedish cohort.In study II, chromosomal microarray analysis was utilized to detect submicroscopic copy number variants in 140 affected Swedish individuals. The most interesting novel finding was a maternally inherited microdeletion in chromosome Xq23 in a male individual, indicating an X-linked recessive inheritance pattern. We highlighted two matrices of candidate gene networks, including genes in the 22q11 region and genes in the Wnt-signaling pathways.The third study applied trio-based whole genome sequencing on DNA from 19 affected individuals and their healthy parents, to identify possible causative variants. The results were filtered using a gene panel with 205 candidate genes. A total of 56 variants in 35 genes were identified, including six de novo variants carried by five different affected individuals. We highlight the sticky protein family as a new candidate gene family due to multiple findings in this study and the involvement of these genes in cell adhesion mechanisms.Study IV focused on the risk for developing urinary bladder cancer in individuals with bladder exstrophy and epispadias complex and consisted of two parts. First, a register study reporting 12 Swedish individuals where almost all of the tumors were of urothelial type and the majority were invasive at the time of diagnosis. Furthermore, a systematic review of the literature summarizing 165 cases, where most of the tumors were non-urothelial, with a majority being adenocarcinomas. Both sub-studies were consistent regarding the young age at cancer diagnosis and mainly in age groups younger than 65 years old. Based on these findings of a higher risk for bladder cancer than previously estimated, we recommend regular screening of the urinary bladder for individuals with bladder exstrophy and epispadias complex, consisting of cystoscopy and urine cytology analysis and starting before the age of 30 years.List of scientific papersI. Evaluation of the ISL1 gene in the pathogenesis of bladder exstrophy in a Swedish cohort. Samara Arkani, Jia Cao, Johanna Lundin, Daniel Nilsson, Thomas Källman, Gillian Barker, Gundela Holmdahl, Christina Clementsson Kockum, Hans Matsson, Agneta Nordenskjöld. Human Genome Variation. (2018) 5, 18009. https://doi.org/10.1038/hgv.2018.9 II. Copy number variants suggest different molecular pathways for the pathogenesis of bladder exstrophy. Agneta Nordenskjöld, Samara Arkani, Maria Pettersson, Johanna Winberg, Jia Cao, Magdalena Fossum, Magnus Anderberg, Gillian Barker, Gundela Holmdahl, Johanna Lundin. American Journal of Medical Genetics. Part A, 2023, Vol.191 (2), p.378-390. https://doi.org/10.1002/ajmg.a.63031 III. Bladder Exstrophy and Epispadias Complex, association with genetic variants based on whole genome sequencing data in 19 family trios. Samara Arkani, Jesper Eisfeldt, Jia Cao, Magnus Anderberg, Gillian Barker, Hans Matsson, Gundela Holmdahl, Anna Lindstrand, Kristina Lagerstedt-Robinson, Agneta Nordenskjöld. [Manuscript]IV. Urinary Bladder Cancer in Bladder Exstrophy and Epispadias Complex: A Swedish Register Study and a Systematic Review of the Literature. Samara Arkani, Anna Skarin Nordenvall, Lotta Renström Koskela, Gisela Reinfeldt Engberg, Ann Nordgren, Agneta Nordenskjöld. JU Open Plus. 1(3):e00012, March 2023. https://doi.org/10.1097/JU9.0000000000000014</p
The History of the Core Dynamos of Mars and the Moon Inferred From Their Crustal Magnetization: A Brief Review
No full textThe core dynamos of Mars and the Moon have distinctly different histories. Mars had no core dynamo at the end of accretion. It took ~100 Myr for the core to create a strong dynamo that magnetized the martian crust. Giant impacts during 4.2-4.0 Ga crippled the core dynamo intermittently, until a thick stagnant lithosphere developed on the surface and reduced the heat flux at the core-mantle boundary, killing the dynamo at ~3.8 Ga. On the other hand, the Moon had a strong core dynamo at the end of accretion that lasted ~100 Myr and magnetized its primordial crust. Either precession of the core, or thermo-chemical convection in the mantle, or chemical convection in the core created a strong core dynamo that magnetized the sources of the isolated magnetic anomalies in later times. Mars and the Moon indicate dynamo reversals and true polar wander. The polar wander of the Moon is easier to explain compared to that of Mars. It was initiated by the mass deficiency at South Pole Aitken basin which moved the basin southward by ~68o relative to the dipole axis of the core field. The formation of mascon maria at later times introduced positive mass anomalies at the surface, forcing the Moon to make an additional ~52o degree polar wander. Interaction of multiple impact shock waves with the dynamo, the abrupt angular momentum transfer to the mantle by the impactors, and the global overturn of the core after each impact were probably the factors causing the dynamo reversal.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
ABHY Associahedra and Newton polytopes of -polynomials for finite type cluster algebras
No full textA new construction of the associahedron was recently given by Arkani-Hamed,
Bai, He, and Yan in connection with the physics of scattering amplitudes. We
show that their construction (suitably understood) can be applied to construct
generalized associahedra of any simply-laced Dynkin type. Unexpectedly, we also
show that this same construction produces Newton polytopes for all the
-polynomials of the corresponding cluster algebras. In addition, we show
that the toric variety associated to the g-vector fan has the property that its
nef cone is simplicial.Comment: 26 pages. v2: added co-author, added section on nef cone of the
g-vector fan, other minor change
On super form factors of half-BPS operators in N=4 super Yang-Mills
No full textOpen Access, (c) The Authors. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited
Search for quantum black hole production in lepton+jet final states using proton-proton collisions at = 13 TeV with the ATLAS detector
No full textA search for quantum black holes in electron+jet and muon+jet invariant mass
spectra is performed with 140 fb of data collected by the ATLAS detector
in proton-proton collisions at = 13 TeV at the Large Hadron
Collider. The observed invariant mass spectrum of lepton+jet pairs is
consistent with Standard Model expectations. Upper limits are set at 95%
confidence level on the production cross-sections times branching fractions for
quantum black holes decaying into a lepton and a quark in a search region with
invariant mass above 2.0 TeV. The resulting quantum black hole lower mass
threshold limit is 9.2 TeV in the Arkani-Hamed-Dimopoulos-Dvali model, and 6.8
TeV in the Randall-Sundrum model.Comment: 41 pages, author list starting page 24, 4 figures, 5 tables,
published in Phys. Rev. D, All figures including auxiliary figures are
available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2018-14
Case study in dimensional deconstruction
No full textWe test dimensional deconstruction on a model of Arkani-Hamed, Cohen, and Georgi that is predicted to have a naturally light composite Higgs boson, i.e., one whose mass M is much less than its binding scale Λ, and whose quartic coupling λ is large, so that its vacuum expectation value v∼M/√λ≪Λ also. We consider two different underlying dynamics—UV completions—at the scale Λ for this model. We find that the expectation from dimensional deconstruction is not realized and that low-energy details depend crucially on the UV completion. In one case, M≪Λ and λ≪1; hence, v∼Λ. In the other, λ can be large or small, but then so is M, and v is still O(Λ).First author draf
Chargino pair production at linear collider and split supersymmetry
No full textRecently Arkani-Hamed and Dimopoulos proposed a supersymmetric model [hep-th/0405159], dubbed "Split supersyrnmetry" in [hep-ph/0406088], which can remove most of the unpleasant shortcomings of TeV Supersymmetry. In this model all scalars except one finely tuned Higgs boson are ultra heavy while the neutralino and chargino, might remain light in order to achieve gauge coupling unification and accord with the dark matter density. In this Letter, we investigated the impact of this new model on chargino pair production at next generation linear colliders. Our numerical results show that this process can be used to probe sneutrino mass up to 10 TeV Therefore, precise measurements of chargino pair production at the linear colliders could distinguish split supersymmetry from TeV supersymmetry. (C) 2004 Elsevier B.V. All rights reserved.Physics, MultidisciplinarySCI(E)29ARTICLE3-4207-21560
Copy number variants suggest different molecular pathways for the pathogenesis of bladder exstrophy
No full textBladder exstrophy is a rare congenital malformation leaving the urinary bladder open in the midline of the abdomen at birth. There is a clear genetic background with chromosome aberrations, but so far, no consistent findings apart from 22q11-duplications detected in about 2%–3% of all patients. Some genes are implicated like the LZTR1, ISL1, CELSR3, and the WNT3 genes, but most are not explained molecularly. We have performed chromosomal microarray analysis on a cohort of 140 persons born with bladder exstrophy to look for submicroscopic chromosomal deletions and duplications. Pathogenic or possibly pathogenic microdeletions or duplications were found in 16 patients (11.4%) and further 9 with unknown significance. Two findings were in regions linked to known syndromes, two findings involved the same gene (MCC), and all other findings were unique. A closer analysis suggests a few gene networks that are involved in the pathogenesis of bladder exstrophy; the WNT-signaling pathway, the chromosome 22q11 region, the RIT2 and POU families, and involvement of the Golgi apparatus. Bladder exstrophy is a rare malformation and is reported to be associated with several chromosome aberrations. Our data suggest involvement of some specific molecular pathways
Patterns of Retirement as Reflected in Income Tax Records for Older Workers
No full textIf retirement means a substantial and sustained reduction in the time spent working for pay or profit, measurement requires a definition of substantial and sufficient observations of the same individuals to determine whether a transition from “working” to “retired” status has occurred. Using the Statistics Canada Longitudinal Administrative Databank, a 20 percent sample of the individual income tax returns of all tax filers since 1980, we identify those with significant labour force attachment at ages 50-52, and follow them year by year. If retired means having no income from employment, the median age of retirement is about 63 for men, 62 for women. That is true for all cohorts. If earning up to half of one’s previous employment income is deemed consistent with being retired, the median age is about 60 for both men and women. Results obtained in this way are consistent with calculations based on Labour Force Survey data.retirement, older workers
Constraining extra space dimensions using precision molecular spectroscopy
No full text9 págs.; 1 fig.; 1 tab.; 7th International Workshop DICE2014 Spacetime – Matter – Quantum Mechanics; Open Access funded by Creative Commons Atribution Licence 3.0Highly accurate measurements of quantum level energies in molecular systems
provide a test ground for new physics, as such effects could manifest themselves as minute shifts
in the quantum level structures of atoms and molecules. For the lightest molecular systems,
neutral molecular hydrogen (H2, HD and D2) and the molecular hydrogen ions (H+2, HD+ and
D+2), weak force effects are several orders weaker than current experimental and theoretical
results, while contributions of Newtonian gravity and the strong force at the characteristic
molecular distance scale of 1 ˚A can be safely neglected. Comparisons between experiment and
QED calculations for these molecular systems can be interpreted in terms of probing large
extra space dimensions, under which gravity could become much stronger than in ordinary
3-D space. Under this assumption, using the spectra of H2 we have derived constraints on
the compactification scales for extra dimensions within the Arkani-Hamed-Dimopoulos-Dvali
(ADD) framework, and constraints on the brane separation and bulk curvature within the
Randall-Sundrum (RS-I and RS-II) frameworks. Published under licence by IOP Publishing LtdThe author is partially
supported by funding from the Spanish Ministerio de Economía y Competitividad, Research
Project FIS2012-38816, and by the Project CONSOLIDER-INGENIO 2010, Programme CPAN
(CSD2007-00042).Peer Reviewe
