4-Dimensional BF Theory as a Topological Quantum Field Theory

Starting from a Lie group G whose Lie algebra is equipped with an invariant nondegenerate symmetric bilinear form, we show that 4-dimensional BF theory with cosmological term gives rise to a TQFT satisfying a generalization of Atiyah's axioms to manifolds equipped with principal G-bundle. The case G = GL(4,R) is especially interesting because every 4-manifold is then naturally equipped with a principal G-bundle, namely its frame bundle. In this case, the partition function of a compact oriented 4-manifold is the exponential of its signature, and the resulting TQFT is isomorphic to that constructed by Crane and Yetter using a state sum model, or by Broda using a surgery presentation of 4-manifolds.Comment: 15 pages in LaTe

Does Access to Health Care Impact Survival Time after Diagnosis of AIDS?

Lack of access to health care is often blamed for poor health outcomes, but this effect is not supported by existing HIV/AIDS literature. The authors examined the association between access to care and survival time after progression to AIDS, using survival analysis methods. This study combined data from two CDC sponsored studies of HIV-infected persons, a cross-sectional interview study and a longitudinal medical record review study. Study subjects included 752 persons who progressed to AIDS before December 31, 1999, and were patients at either of two major HIV care facilities in Detroit, MIchigan. Separate statistical models were used to test associations between survival time after meeting the criteria for AIDS and two indicators of access to health care: (1) perceived access to health care and (2) health care utilization patterns. Perceived access was not associated with survival time after AIDS, but patterns of health care utilization were significantly associated with survival time after AIDS (HR = 2.04, p < 0.001). Individuals who received a greater proportion of their care in the ER had a worse survival prognosis than those who received more of their health care in an outpatient clinic setting. It is crucial that we provide HIV-infected populations with tools that enable them to access a regular source of health care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63272/1/10872910252972276.pd

Interaction of Laser Radiation with Plasmas and Nonadiabatic Motion of Particles in Magnetic Fields

Contains research objectives and reports on one research project.United States Atomic Energy Commission (Contract AT(30-1)-3285

A unified Witten-Reshetikhin-Turaev invariant for integral homology spheres

We construct an invariant J_M of integral homology spheres M with values in a completion \hat{Z[q]} of the polynomial ring Z[q] such that the evaluation at each root of unity \zeta gives the the SU(2) Witten-Reshetikhin-Turaev invariant \tau_\zeta(M) of M at \zeta. Thus J_M unifies all the SU(2) Witten-Reshetikhin-Turaev invariants of M. As a consequence, \tau_\zeta(M) is an algebraic integer. Moreover, it follows that \tau_\zeta(M) as a function on \zeta behaves like an ``analytic function'' defined on the set of roots of unity. That is, the \tau_\zeta(M) for all roots of unity are determined by a "Taylor expansion" at any root of unity, and also by the values at infinitely many roots of unity of prime power orders. In particular, \tau_\zeta(M) for all roots of unity are determined by the Ohtsuki series, which can be regarded as the Taylor expansion at q=1.Comment: 66 pages, 8 figure

Interaction of Laser Radiation with Plasmas and Nonadiabatic Motion of Particles in Magnetic Fields

Contains research objectives.United States Atomic Energy Commission (Contract AT(30-1)-3285

Instrumentation progress at the Giant Magellan Telescope project

Instrument development for the 24m Giant Magellan Telescope (GMT) is described: current activities, progress, status, and schedule. One instrument team has completed its preliminary design and is currently beginning its final design (GCLEF, an optical 350-950 nm, high-resolution and precision radial velocity echelle spectrograph). A second instrument team is in its conceptual design phase (GMACS, an optical 350-950 nm, medium resolution, 6-10 arcmin field, multiobject spectrograph). A third instrument team is midway through its preliminary design phase (GMTIFS, a near-IR YJHK diffraction-limited imager/integral-field-spectrograph), focused on risk reduction prototyping and design optimization. A fourth instrument team is currently fabricating the 5 silicon immersion gratings needed to begin its preliminary design phase (GMTNIRS, a simultaneous JHKLM high-resolution, AO-fed, echelle spectrograph). And, another instrument team is focusing on technical development and prototyping (MANIFEST, a facility robotic, multifiber-feed, with a 20 arcmin field of view). In addition, a medium-field (6 arcmin, 0.06 arcsec/pix) optical imager will support telescope and AO commissioning activities, and will excel at narrow-band imaging. In the spirit of advancing synergies with other groups, the challenges of running an ELT instrument program and opportunities for cross-ELT collaborations are discussed

The impact of human immunodeficiency virus infection on drug-resistant tuberculosis.

Infection with human immunodeficiency virus (HIV) has been associated with increased rates of single- and multidrug-resistant (MDR) tuberculosis in the New York City area. In order to examine the relationship of HIV infection to drug-resistant tuberculosis in other selected regions of the United States, we established a registry of cases of culture-proven tuberculosis. Data were collected from sites participating in an NIH-funded, community-based HIV clinical trials group. All cases of tuberculosis, regardless of HIV status, which occurred between January 1992 and June 1994 were recorded. Overall, 1,373 cases of tuberculosis were evaluated, including 425 from the New York City area, and 948 from seven other metropolitan areas. The overall prevalence of resistance to one or more drugs was 20.4%, and 5.6% of isolates were resistant to both isoniazid and rifampin (MDR). In the New York City area, HIV-infected patients were significantly more likely than persons not known to be HIV-infected, to have resistance to at least one drug (37% versus 19%) and MDR (19% versus 6%). In other geographic areas, overall drug resistance was 16%, and only 2.2% of isolates were MDR. In multiple logistic regression analyses, HIV infection was shown to be a risk factor for drug-resistant tuberculosis, independent of geographic location, history of prior therapy, age, and race. We concluded that HIV infection is associated with increased rates of resistance to antituberculosis drugs in both the New York City area and other geographic areas. MDR tuberculosis is occurring predominantly in the New York City area and is highly correlated with HIV infection

The impact of human immunodeficiency virus infection on drug-resistant tuberculosis.

Infection with human immunodeficiency virus (HIV) has been associated with increased rates of single- and multidrug-resistant (MDR) tuberculosis in the New York City area. In order to examine the relationship of HIV infection to drug-resistant tuberculosis in other selected regions of the United States, we established a registry of cases of culture-proven tuberculosis. Data were collected from sites participating in an NIH-funded, community-based HIV clinical trials group. All cases of tuberculosis, regardless of HIV status, which occurred between January 1992 and June 1994 were recorded. Overall, 1,373 cases of tuberculosis were evaluated, including 425 from the New York City area, and 948 from seven other metropolitan areas. The overall prevalence of resistance to one or more drugs was 20.4%, and 5.6% of isolates were resistant to both isoniazid and rifampin (MDR). In the New York City area, HIV-infected patients were significantly more likely than persons not known to be HIV-infected, to have resistance to at least one drug (37% versus 19%) and MDR (19% versus 6%). In other geographic areas, overall drug resistance was 16%, and only 2.2% of isolates were MDR. In multiple logistic regression analyses, HIV infection was shown to be a risk factor for drug-resistant tuberculosis, independent of geographic location, history of prior therapy, age, and race. We concluded that HIV infection is associated with increased rates of resistance to antituberculosis drugs in both the New York City area and other geographic areas. MDR tuberculosis is occurring predominantly in the New York City area and is highly correlated with HIV infection