Intrinsic Spectral Geometry of the Kerr-Newman Event Horizon

We uniquely and explicitly reconstruct the instantaneous intrinsic metric of the Kerr-Newman Event Horizon from the spectrum of its Laplacian. In the process we find that the angular momentum parameter, radius, area; and in the uncharged case, mass, can be written in terms of these eigenvalues. In the uncharged case this immediately leads to the unique and explicit determination of the Kerr metric in terms of the spectrum of the event horizon. Robinson's ``no hair" theorem now yields the corollary: One can ``hear the shape" of noncharged stationary axially symmetric black hole space-times by listening to the vibrational frequencies of its event horizon only.Comment: Final version with improved abstract, updated references, corrected typos, and additional discussio

Heat-Killed Trypanosoma cruzi Induces Acute Cardiac Damage and Polyantigenic Autoimmunity

Chagas heart disease, caused by the protozoan parasite Trypanosoma cruzi, is a potentially fatal cardiomyopathy often associated with cardiac autoimmunity. T. cruzi infection induces the development of autoimmunity to a number of antigens via molecular mimicry and other mechanisms, but the genesis and pathogenic potential of this autoimmune response has not been fully elucidated. To determine whether exposure to T. cruzi antigens alone in the absence of active infection is sufficient to induce autoimmunity, we immunized A/J mice with heat-killed T. cruzi (HKTC) emulsified in complete Freund's adjuvant, and compared the resulting immune response to that induced by infection with live T. cruzi. We found that HKTC immunization is capable of inducing acute cardiac damage, as evidenced by elevated serum cardiac troponin I, and that this damage is associated with the generation of polyantigenic humoral and cell-mediated autoimmunity with similar antigen specificity to that induced by infection with T. cruzi. However, while significant and preferential production of Th1 and Th17-associated cytokines, accompanied by myocarditis, develops in T. cruzi-infected mice, HKTC-immunized mice produce lower levels of these cytokines, do not develop Th1-skewed immunity, and lack tissue inflammation. These results demonstrate that exposure to parasite antigen alone is sufficient to induce autoimmunity and cardiac damage, yet additional immune factors, including a dominant Th1/Th17 immune response, are likely required to induce cardiac inflammation

Stress response in pied flycatchers (Ficedula hypoleuca) in relation to monoterritorial and polyterritorial behavior

When facing life-threatening perturbation the following stress reaction will usually turn current behavior towards survival behaviors. However, this can have a potential fitness trade-off if it turns behavior away from reproduction towards survival. Animals will therefore try to modify their sensitivity to stressors so that they will turn current behavior towards survival when this gives the highest fitness. Animals that, for varies reasons, are more reactive to stressors should therefore avoid behavior that can more quickly resemble an emergency stress response. In a pied flycatcher (Ficedula hypoleuca) population, only a portion of the males becomes polyterritorial while the rest stays monoterritorial. Polyterritoriality is an energetically demanding strategy, and the behavior could trigger emergency stress responses more quickly than monoterritorial behavior. The hypothesis in this study is therefore that pied flycatcher males that are more sensitive towards stressors should avoid polyterritorial behavior, and males with this behavior should also show a suppressed stress response in order to continue to be polyterritorial. To examine this male pied flycatcher were captured twice, once in the territorial establishment period and once in the nestling feeding period. Breathing rate and corticosterone levels were used as stress response measurements. Three predictions were tested: 1. Pre-breeding males that later become polyterritorial will show a lower acute stress response than males who stay monoterritorial. 2. Males that have become polyterritorial will show a lower acute stress response than males who stay monoterritorial. 3. Males that are polyterritorial will have higher baseline corticosterone levels than monoterritorial, because polyterritoriality is an energetically demanding strategy. None of the predictions regarding stress response tested in this thesis showed any significant difference between mono- and polyterritorial males. This suggests that responsiveness to stressors does not affect the likelihood of becoming polyterritorial. Other proximate explanations for this behavior are necessary, or a combination of many factors together could explain why some males become polyterritorial. Further, the tendency for higher baseline corticosterone levels in polyterritorial males during the nestling feeding period supports previous studies that polyterritorial behavior is in fact an energetically demanding strategy