Thyroid Hormone as a Method of Reducing Damage to Donor Hearts after Circulatory Arrest

There is a chronic lack of donor hearts to meet the need for heart transplant both in the US and worldwide. Further, the use of available hearts is limited by the short period between collection and implantation during which the heart can be safely preserved ex vivo. Using mid-thermic Langendorff machine perfusion, we have been able to preserve the metabolic function of a healthy heart for up to 8 hours, twice the limit for current static cold storage. We have also been able to preserve the metabolic function of a damaged DCD Heart collected 30 minutes after cardiac arrest for a period of 8 hours. We further investigated whether it was possible to improve the preservation of DCD heart using treatment with 10 μM Triiodothyronine to stimulate the tissue metabolism and we did find a reduction in damage markers in the treated DCD hearts as compared to the untreated group

Should merger policy be changed? An antitrust perspective

Consolidation and merger of corporations ; Antitrust law

Liquidity Constraints and Imperfect Information in Subprime Lending

We present new evidence on consumer liquidity constraints and the credit market conditions that might give rise to them. Our analysis is based on unique data from a large auto sales company that serves the subprime market. We first document the role of short-term liquidity in driving purchasing behavior, including sharp increases in demand during tax rebate season and a high sensitivity to minimum down payment requirements. We then explore the informational problems facing subprime lenders. We find that default rates rise significantly with loan size, providing a rationale for lenders to impose loan caps because of moral hazard. We also find that borrowers at the highest risk of default demand the largest loans, but the degree of adverse selection is mitigated substantially by effective risk-based pricing.

Multifunction tests of a frequency domain based flutter suppression system

The process is described of analysis, design, digital implementation, and subsonic testing of an active control flutter suppression system for a full span, free-to-roll wind tunnel model of an advanced fighter concept. The design technique uses a frequency domain representation of the plant and used optimization techniques to generate a robust multi input/multi output controller. During testing in a fixed-in-roll configuration, simultaneous suppression of both symmetric and antisymmetric flutter was successfully shown. For a free-to-roll configuration, symmetric flutter was suppressed to the limit of the tunnel test envelope. During aggressive rolling maneuvers above the open-loop flutter boundary, simultaneous flutter suppression and maneuver load control were demonstrated. Finally, the flutter damping controller was reoptimized overnight during the test using combined experimental and analytical frequency domain data, resulting in improved stability robustness