Incapacitated Patients' Wellbeing: Surrogate Decision Making

Patients' wellbeing often depends on making the right decision with regards to their healthcare treatment and other decisions relating to their health care or finances in terms of their end of life. If they are unable to make decisions for themselves, other people have to make those decisions on their behalf. This important task is described in literature as surrogate decision making. We survey and illustrate several important issues that are associated with surrogate decision making and provide an overview of the factors that have been found to affect its accuracy. Selection of a surrogate decision maker has been found to be affected by the beneficiary’s nationality, risk attitudes, and personality and by specific qualities of the surrogate. Decision accuracy (as indexed by matching between choices for self or relative) has been found to be affected by factors such as nationality, surrogate qualities, surrogate person choice, risk attitudes and personality

Noncommutative Solitons and Intersecting D-Branes

We construct intersecting D-branes as noncommutative solitons in bosonic and type II string theory. ``Defect'' branes which are D-branes containing bubbles of the closed string vacuum play an important role in the construction.Comment: 17 pages, harvmac; published version with added clarification

Large Magnetic Fields and Motions of OH Masers in W75 N

We report on a second epoch of VLBA observations of the 1665 and 1667 MHz OH masers in the massive star-forming region W75 N. We find evidence to confirm the existence of very strong (~40 mG) magnetic fields near source VLA 2. The masers near VLA 2 are dynamically distinct and include a very bright spot apparently moving at 50 km/s relative to those around VLA 1. This fast-moving spot may be an example of a rare class of OH masers seen in outflows in star-forming regions. Due to the variability of these masers and the rapidity of their motions, tracking these motions will require multiple observations over a significantly shorter time baseline than obtained here. Proper motions of the masers near VLA 1 are more suggestive of streaming along magnetized shocks rather than Keplerian rotation in a disk. The motions of the easternmost cluster of masers in W75 N (B) may be tracing slow expansion around an unseen exciting source.Comment: 7 pages including 4 figures (2 color) & 3 tables, to appear in Ap

Boundary String Field Theory of the DDbar System

We develop the boundary string field theory approach to tachyon condensation on the DDbar system. Particular attention is paid to the gauge fields, which combine with the tachyons in a natural way. We derive the RR-couplings of the system and express the result in terms of Quillen's superconnection. The result is related to an index theorem, and is thus shown to be exact.Comment: 38 pages, harvmac. v2: added reference

The role of narrow-angle forward surface scatter and particulate scatter in exoplanet exploration

It is often thought that because of the very small solid angle subtended by the field-of-view of the coronagraph, scattered light from optical surfaces will have no effect on images recorded for terrestrial exoplanet spectroscopy. In this paper, we examine mirror surface scatter and particulate contamination scatter as sources of background light or noise signal in large aperture terrestrial exoplanet telescope/coronagraph systems. Scattered light control to one part in 10^(+10) or better is required for exoplanet exploration. We will discuss the optical fabrication tolerances necessary to minimize narrowangle forward scatter and their relative effects upon direct imaging coronagraph instruments used to characterize terrestrial exoplanets

Beta lives - some statistical perspectives on the capital asset pricing model

This note summarizes some technical issues relevant to the use of the idea of excess return in empirical modelling. We cover the case where the aim is to construct a measure of expected return on an asset and a model of the CAPM type is used. We review some of the problems and show examples where the basic CAPM may be used to develop other results which relate the expected returns on assets both to the expected return on the market and other factors

On the stability and spectrum of non-supersymmetric AdS(5) solutions of M-theory compactified on Kahler-Einstein spaces

Eleven-dimensional supergravity admits non-supersymmetric solutions of the form AdS(5)xM(6) where M(6) is a positive Kahler-Einstein space. We show that the necessary and sufficient condition for such solutions to be stable against linearized bosonic supergravity perturbations can be expressed as a condition on the spectrum of the Laplacian acting on (1,1)-forms on M(6). For M(6)=CP(3), this condition is satisfied, although there are scalars saturating the Breitenlohner-Freedman bound. If M(6) is a product S(2)xM(4) (where M(4) is Kahler-Einstein) then there is an instability if M(4) has a continuous isometry. We show that a potential non-perturbative instability due to 5-brane nucleation does not occur. The bosonic Kaluza-Klein spectrum is determined in terms of eigenvalues of operators on M(6).Comment: 21 pages. v2: Includes SU(4) quantum numbers for CP3 case, typos fixed, refs adde