Photoelectron-photofragment coincidence ~PPC! spectroscopy has been used to study the dissociative photodetachment of H2O2 2 and D2O2 . The observed partitioning of photoelectron and photofragment translational energies provides information on the dynamics in the transition state region of the reaction between two hydroxyl radicals: OH1OH→O(P)1H2O. The data reveal vibrationally resolved product...

It is pointed out that translational and (overall) rotational motions provide the important entropic driving force for enzymic and intramolecular rate accelerations and the chelate effect; internal rotations and unusually severe orientational requirements are generally of secondary importance. The loss of translational and (overall) rotational entropy for 2 --> 1 reactions in solution is ordina...

The Chlamydomonas reinhardtii chloroplast atpB mRNA contains sequences at its 3' end that can form a complex stem/loop structure. Deletions of part or all of this sequence in transformed C. reinhardtii cells led to decreased atpB mRNA accumulation, whereas transcription rates were unaffected. The reduction of mRNA to 20% to 35% of wild-type levels in transformants without 3' stem/loops was corr...

Posttranscriptional regulation is of critical importance during mammalian spermiogenesis. A set of mRNAs that encode proteins critical to normal sperm formation are synthesized early in the process of male germ cell differentiation and are stored in a repressed state. These mRNAs are subsequently translationally activated during the process of spermatid elongation and maturation. Of note, the t...

Experiments quantifying the rotational and translational motion of particles in a dense, driven, 2D granular gas floating on an air table reveal that kinetic energy is divided equally between the two translational and one rotational degrees of freedom. This equipartition persists when the particle properties, confining pressure, packing density, or spatial ordering are changed. While the transl...

Recently, femtosecond laser techniques have been developed that are capable of bringing gas molecules to extremely fast rotation in a very short time, while keeping their translational motion relatively slow. Here we study collisional equilibration dynamics of this new state of molecular gases. We show that the route to equilibrium starts with a metastable 'gyroscopic stage' in the course of wh...

We investigate the free cooling of inelastic rough spheres in the presence of Coulomb friction. Depending on the coefficients of normal restitution ǫ and Coulomb friction μ, we find qualitatively different asymptotic states. For nearly complete normal restitution (ǫ close to 1) and large μ, friction does not change the cooling properties qualitatively compared to a constant coefficient of tange...

The inheritance of the apoprotein-E isoprotein polymorphism in man has been studied by pedigree analysis. Alternative genotypes have been identified by the use of isoelectric focusing and two dimensional electrophoresis. A single locus three allele model can account for the inherited differences. In addition to the major bands there are also minor bands which may differ in charge or molecular w...

We report a joint theoretical and experimental study on the photodissociation of the C3H2 isomer propargylene, HCCCH, combining velocity map imaging with nonadiabatic trajectory surface hopping calculations. Propargylene loses an H-atom, after laser excitation at around 250 nm, presumably to the T6 state. The photofragment angular distribution exhibits only a very small anisotropy, but the H-at...

Cardiac voltage-gated sodium channels (Nav1.5) play an essential role in regulating cardiac electric activity by initiating and propagating action potentials in the heart. Altered Nav1.5 function is associated with multiple cardiac diseases including long-QT3 and Brugada syndrome. Here, we show that Nav1.5 is subject to palmitoylation, a reversible post-translational lipid modification. Palmito...