818 research outputs found
Correspondence: No substantial long-term bias in the Cenozoic benthic foraminifera oxygen-isotope record
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Kahler Independence of the G2-MSSM
The G2-MSSM is a model of particle physics coupled to moduli fields with
interesting phenomenology both for colliders and astrophysical experiments. In
this paper we consider a more general model - whose moduli Kahler potential is
a completely arbitrary G2-holonomy Kahler potential and whose matter Kahler
potential is also more general. We prove that the vacuum structure and spectrum
of BSM particles is largely unchanged in this much more general class of
theories. In particular, gaugino masses are still supressed relative to the
gravitino mass and moduli masses. We also consider the effects of higher order
corrections to the matter Kahler potential and find a connection between the
nature of the LSP and flavor effects.Comment: Final version, matches the version published in JHE
Atypical Presentation of Upshaw Schulman Syndrome: A Case Report
Thrombotic thrombocytopenic purpura (TTP) is a rare coagulation disorder with a typical clinical presentation of low platelets and excessive clotting. Mortality for this disorder may be high if untreated and therefore necessitates a high clinical suspicion. Here we describe a 46-year-old African American woman with a past medical history of multiple cerebrovascular accidents presenting to hematology after a suspected diagnosis of TTP. Presumptive diagnosis of acquired TTP called for treatment with IVIg, but a diagnosis of congenital TTP (Upshaw Schulman syndrome) was made after testing showed a lack of ADAMTS13 antibodies. Treatment with fresh frozen plasma (FFP) showed increase in ADAMTS13 levels which further supported the diagnosis of Upshaw Schulman syndrome. Genomic analysis of ADAMTS13 showed normal sequencing and was not consistent with the diagnosis of Upshaw Schulman syndrome. No prior literature provides an explanation for these findings. This new presentation of a well-classified disease suggests a potential subcategory of TTP that may traditionally be misdiagnosed. Potential explanations for this disease presentation may include IgA-mediated TTP, epigenetic changes of ADAMTS13 expression, or limitations of current testing modalities
Innovative learning at The University of Edinburgh
The activities available to civil engineering students during the University of Edinburgh's innovative learning week in 2012 were examined. The academic staff proposed a wide range of possible activities and student participation was optional. Popular activities were those with a ‘hands-on’ element: making or doing something. The practical activities offered included designing and building trebuchets, relaying railway permanent way on a heritage railway, practical workshops on engineering in international development and learning to juggle. These activities suggested that heuristic learning by trial and error was likely to enhance the visualisation skills that contribute to good engineering design. Further, the linking of achievement to purposeful practice rather than innate talent could inform teaching methods in the future. They also showed that in some cases safety culture messages were still not fully assimilated by students
Compactification on negatively curved manifolds
We show that string/M theory compactifications to maximally symmetric
space-times using manifolds whose scalar curvature is everywhere negative, must
have significant warping, large stringy corrections, or both.Comment: 18 pages, JHEP3.cl
Symmetries of Abelian Orbifolds
Using the Polya Enumeration Theorem, we count with particular attention to
C^3/Gamma up to C^6/Gamma, abelian orbifolds in various dimensions which are
invariant under cycles of the permutation group S_D. This produces a collection
of multiplicative sequences, one for each cycle in the Cycle Index of the
permutation group. A multiplicative sequence is controlled by its values on
prime numbers and their pure powers. Therefore, we pay particular attention to
orbifolds of the form C^D/Gamma where the order of Gamma is p^alpha. We propose
a generalization of these sequences for any D and any p.Comment: 75 pages, 13 figures, 30 table
Counting Orbifolds
We present several methods of counting the orbifolds C^D/Gamma. A
correspondence between counting orbifold actions on C^D, brane tilings, and
toric diagrams in D-1 dimensions is drawn. Barycentric coordinates and scaling
mechanisms are introduced to characterize lattice simplices as toric diagrams.
We count orbifolds of C^3, C^4, C^5, C^6 and C^7. Some remarks are made on
closed form formulas for the partition function that counts distinct orbifold
actions.Comment: 69 pages, 9 figures, 24 tables; minor correction
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