Laser spectroscopic characterization of the nuclear-clock isomer 229m^{229m}Th

The isotope $^{229}$Th is the only nucleus known to possess an excited state $^{229m}$Th in the energy range of a few electron volts, a transition energy typical for electrons in the valence shell of atoms, but about four orders of magnitude lower than common nuclear excitation energies. A number of applications of this unique nuclear system, which is accessible by optical methods, have been proposed. Most promising among them appears a highly precise nuclear clock that outperforms existing atomic timekeepers. Here we present the laser spectroscopic investigation of the hyperfine structure of $^{229m}$Th$^{2+}$, yielding values of fundamental nuclear properties, namely the magnetic dipole and electric quadrupole moments as well as the nuclear charge radius. After the recent direct detection of this long-searched-for isomer, our results now provide detailed insight into its nuclear structure and present a method for its non-destructive optical detection.Comment: 18 page

Phage treatment of human infections

Phages as bactericidal agents have been employed for 90 years as a means of treating bacterial infections in humans as well as other species, a process known as phage therapy. In this review we explore both the early historical and more modern use of phages to treat human infections. We discuss in particular the little-reviewed French early work, along with the Polish, US, Georgian and Russian historical experiences. We also cover other, more modern examples of phage therapy of humans as differentiated in terms of disease. In addition, we provide discussions of phage safety, other aspects of phage therapy pharmacology, and the idea of phage use as probiotics