Four curious supergravities

We consider four supergravities with 16+16, 32+32, 64+64, 128+128 degrees of freedom displaying some curious properties: (1) They exhibit minimal supersymmetry (N=1, 2, 2, 1) but maximal rank (r=7, 6, 4, 0) of the scalar coset in D=4, 5, 7, 11. (2) They couple naturally to supermembranes and admit these membranes as solutions. (3) Although the D=4, 5, 7 supergravities follow from truncating the maximally supersymmetric ones, there nevertheless exist M-theory compactifications with G2, SU(3), SU(2) holonomy having these supergravities as their massless sectors. (4) They reduce to N=1, 2, 4, 8 theories all with maximum rank 7 in D=4 which (5) correspond to 0, 1, 3, 7 lines of the Fano plane and hence admit a division algebra (R,C,H,O) interpretation consistent with the black-hole/qubit correspondence, (6) are generalized self-mirror and hence (7) have vanishing on-shell trace anomaly.Comment: 16 pages late

Spectrum of D=6, N=4b Supergravity on AdS_3 x S^3

The complete spectrum of D=6, N=4b supergravity with n tensor multiplets compactified on AdS_3 x S^3 is determined. The D=6 theory obtained from the K_3 compactification of Type IIB string requires that n=21, but we let n be arbitrary. The superalgebra that underlies the symmetry of the resulting supergravity theory in AdS_3 coupled to matter is SU(1,1|2)_L x SU(1,1|2)_R. The theory also has an unbroken global SO(4)_R x SO(n) symmetry inherited from D=6. The spectrum of states arranges itself into a tower of spin-2 supermultiplets, a tower of spin-1, SO(n) singlet supermultiplets, a tower of spin-1 supermultiplets in the vector representation of SO(n) and a special spin-1/2 supermultiplet also in the vector representation of SO(n). The SU(2)_L x SU(2)_R Yang-Mills states reside in the second level of the spin-2 tower and the lowest level of the spin-1, SO(n) singlet tower and the associated field theory exhibits interesting properties.Comment: 37 pages, latex, 5 tables and 3 figures, typos corrected, a reference adde

Real Special Geometry

We give a coordinate-free description of real manifolds occurring in certain four dimensional supergravity theories with antisymmetric tensor fields. The relevance of the linear multiplets in the compactification of string and five-brane theories is also discussed.Comment: 10 pgs (TeX with Harvmac), CERN-TH.7211/94, UCLA/94/TEP/14, POLFIS-TH.01/9

Generalized mirror symmetry and trace anomalies

We consider compactification of M-theory on X7 with betti numbers (b_0, b_1, b_2, b_3, b_3, b_2, b_1, b_0) and define a generalized mirror symmetry (b_0, b_1, b_2, b_3) goes to (b_0, b_1, b_2 -rho/2, b_3+rho/2)$ under which rho = 7b_0-5b_1+3b_2 -b_3 changes sign. Generalized self-mirror theories with rho=0 have massless sectors with vanishing trace anomaly (before dualization). Examples include pure supergravity with N \geq 4 and supergravity plus matter with N \leq 4.Comment: 19 pages late

Incomplete Orthogonal Factorization Methods Using Givens Rotations II: Implementation and Results

We present, implement and test a series of incomplete orthogonal factorization methods based on Givens rotations for large sparse unsymmetric matrices. These methods include: column-Incomplete Givens Orthogonalization (cIGO-method), which drops entries by position only; column-Threshold Incomplete Givens Orthogonalization (cTIGO-method) which drops entries dynamically by both their magnitudes and positions and where the reduction via Givens rotations is done in a column-wise fashion; and, row-Threshold Incomplete Givens Orthogonalization (r-TIGO-method) which again drops entries dynamically, but only magnitude is now taken into account and reduction is performed in a row-wise fashion. We give comprehensive accounts of how one would code these algorithms using a high level language to ensure efficiency of computation and memory use. The methods are then applied to a variety of square systems and their performance as preconditioners is tested against standard incomplete LU factorization techniques. For rectangular matrices corresponding to least-squares problems, the resulting incomplete factorizations are applied as preconditioners for conjugate gradients for the system of normal equations. A comprehensive discussion about the uses, advantages and shortcomings of these preconditioners is given

Freudenthal Dual Lagrangians

The global U-dualities of extended supergravity have played a central role in differentiating the distinct classes of extremal black hole solutions. When the U-duality group satisfies certain algebraic conditions, as is the case for a broad class of supergravities, the extremal black holes enjoy a further symmetry known as Freudenthal duality (F-duality), which although distinct from U-duality preserves the Bekenstein-Hawking entropy. Here it is shown that, by adopting the doubled Lagrangian formalism, F-duality, defined on the doubled field strengths, is not only a symmetry of the black hole solutions, but also of the equations of motion themselves. A further role for F-duality is introduced in the context of world-sheet actions. The Nambu-Goto world-sheet action in any (t, s) signature spacetime can be written in terms of the F-dual. The corresponding field equations and Bianchi identities are then related by F-duality allowing for an F-dual formulation of Gaillard-Zumino duality on the world-sheet. An equivalent polynomial "Polyakov- type" action is introduced using the so-called black hole potential. Such a construction allows for actions invariant under all groups of type E7, including E7 itself, although in this case the stringy interpretation is less clear.Comment: 1+16 pages, 1 Table, updated to match published versio

Putting String/Fivebrane Duality to the Test

According to string/fivebrane duality, the Green-Schwarz factorization of the $D=10$ spacetime anomaly polynomial $I_{12}$ into $X_4\, X_8$ means that just as $X_4$ is the anomaly polynomial of the $d=2$ string worldsheet so $X_8$ should be the anomaly polynomial of the $d=6$ fivebrane worldvolume. To test this idea we perform a fivebrane calculation of $X_8$ and find perfect agreement with the string one--loop result.Comment: 14 pages, CERN TH-6614/92, CTP-TAMU 60/9

Looking forward to a safer future: The new WHO guidelines for safe surgery

Each year in Australia there are approximately 2 million hospital admissions for surgical services (Australia’s Health, 2008) and this number is set to grow significantly, with forecasts of at least a 22% increase by 2021 (Birrell, Hawthorne & Rapson, 2003). Surprisingly, for such a high-risk high-volume specialty, we have very little data on perioperative adverse events. This lack of even basic data means that we are unable to track event rates, leaving us oblivious to the full extent of the problem. Research on intraoperative adverse events tells us that the rate of major complications is between 3-16%, with a mortality rate of 0.4-0.8%. (Kable, Gibbered & Spigelman, 2002; Gawande et al, 1999). Applying the lowest of these rates (3% & 0.4%) to Australia’s surgical population reveals that a staggering 60,000 patients annually suffer significant complications, with 8000 patients dieing during or immediately after surgery as a result of adverse events. This is indeed a significant number, and given that the research indicates that nearly half of these events are preventable (Kable, Gibbered & Spigelman, 2002; Gawande et al, 1999), one that clearly needs addressing. This paper will review the research on perioperative safety and adverse events and examine some of the safety strategies put forward in the new World Health Organizations (WHO) Guidelines for Safe Surgery. These guidelines were developed for the WHO by renowned perioperative safety champion Dr Atul Gawande and contain recommendations for ‘safer surgery practices’ that have been demonstrated to reduce adverse events

Utilising the Clinical Excellence Commission’s Performance Indicators for Quality Use of Medicines

Like other aspects of health care, Quality Use of Medicine (QUM) can be considered in terms of structures, processes and outcomes. These components of QUM can be measured with performance indicators. This poster describes the Clinical Excellence Commissions (CEC) new performance indicators and their use in a warfarin practice improvement project. Aim: - To measure performance indicators in order to; Comprehensively audit warfarin therapy. - Benchmarking current practices. - Identify opportunities for practice improvement. - Measure practice change\u3e Method: Auditing structures, processes, and outcomes requires different tools and methods. For this project, the following tools were utilised; - The CEC Medication Safety Self Assessment for Antithrombotic Therapy in Australian Hospitals tool (MSSA-AT) was selected to provide qualitative data on hospital structure, culture, systems, policies, procedures and activities. - The CEC and NSW TAG Indicators for Quality Use of Medicines in Australian Hospitals were used to review processes. These indicators provided quantitative data regarding the impact and effectiveness of systems, policies and procedures. Indicators from Australia Council of Health Care Standards (ACHS) provided quantitative data related to patient outcomes. Results: Together, the tools provided a comprehensive evaluation of warfarin therapy at St Vincents Private Hospital. The MSSA-AT provided a baseline measure of performance, a benchmark of practices, and numerous areas for practice improvement. The CEC’s process indicators provided a picture of current practices. This data, when benchmarked, identified strengths and opportunities and the ongoing measurement of these indicators will provide ongoing evidence of practice change. The ACHS outcomes date provided evidence that, although room for improvement, outcomes remained comparable with national data. Conclusion: Using performance indicators enabled a comprehensive review of clinical practice by providing information from a variety of sources about different aspects of therapy. This information can then facilitate the practice improvement process