Successful heart transplantation from a donor with Ullrich congenital muscular dystrophy.

Heart transplantation is the most effective therapy for children with end-stage heart disease; however, its use is limited by the number of donor organs available. This shortage may be further compounded by concerns about organ quality, leading to refusal of potential donor organ offers. We report on the successful transplantation and 5-year follow-up of a heart from a donor with Ullrich congenital muscular dystrophy (UCMD). The candidate was critically ill at the time of the transplant and the donor organ was declined repeatedly on the match run list due to concerns about organ quality, despite having normal cardiac function by echocardiography on minimal inotropic support. We believe the diagnosis of "muscular dystrophy" in the donor combined with a lack of understanding about the specifics of the diagnosis of UCMD enabled our candidate to receive a primary offer for this organ. We are unaware of any previous reports of the use of a heart from a donor with UCMD for orthotopic heart transplantation in adults or children.

Superfluid-helium converter for accumulation and extraction of ultracold neutrons.

We report the first successful extraction of accumulated ultracold neutrons (UCN) from a converter of superfluid helium, in which they were produced by downscattering neutrons of a cold beam from the Munich research reactor. Windowless UCN extraction is performed in vertical direction through a mechanical cold valve. This prototype of a versatile UCN source is comprised of a novel cryostat designed to keep the source portable and to allow for rapid cooldown. We measured time constants for UCN storage and extraction into a detector at room temperature, with the converter held at various temperatures between 0.7 and 1.3 K. The UCN production rate inferred from the count rate of extracted UCN is close to the theoretical expectation.

Cold neutron energy dependent production of ultracold neutrons in solid deuterium.

A measurement of the production of ultracold neutrons from velocity-selected cold neutrons on gaseous and solid deuterium targets is reported. The expected energy dependence for two-particle collisions with well defined neutron and Maxwell-Boltzmann distributed molecular velocities is found for the gas target. The solid target data agree in shape with the phonon density-of-states curve and provide strong evidence for the phonon model including multiphonon excitations.

Direct experimental limit on neutron-mirror-neutron oscillations.

In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron n', could potentially mix and undergo nn' oscillations. The interaction of an ordinary magnetic field with the ordinary neutron would lift the degeneracy between the mirror partners, diminish the n' amplitude in the n wave function and, thus, suppress its observability. We report an experimental comparison of ultracold neutron storage in a trap with and without superimposed magnetic field. No influence of the magnetic field is found and, assuming negligible mirror magnetic fields, a limit on the oscillation time taunn' > 103 s (95% C.L.) is derived.