Temporal and structural genetic variation in reindeer () associated with the pastoral transition in Northwestern Siberia.

Just as the domestication of livestock is often cited as a key element in the Neolithic transition to settled, the emergence of large-scaled reindeer husbandry was a fundamental social transformation for the indigenous peoples of Arctic Eurasia. To better understand the history of reindeer domestication, and the genetic processes associated with the pastoral transition in the Eurasian Arctic, we analyzed archaeological and contemporary reindeer samples from Northwestern Siberia. The material represents genealogies spanning from 15,000 years ago to the 18th century, as well as modern samples from the wild Taĭmyr population and from domestic herds managed by Nenetses.

Roaming dynamics in formaldehyde-d2 dissociation.

State-resolved photodissociation dynamics of formaldehyde-d(2), i.e., D(2)CO, at energies slightly above the deuterium atom elimination channel have been studied both experimentally and theoretically.

Masked velocity map imaging: a one-laser-beam Doppler-free spectroscopic technique.

A novel spectroscopic technique has been developed which makes it possible to record Doppler-free resonance-enhanced multiphoton ionization (REMPI) spectra with just one laser beam. The approach simply involves masking the outer side of the phosphor screen under velocity map imaging conditions so that only those species having no velocity component parallel to the laser beam propagation direction are detected. The benefits of this method are demonstrated in spectroscopic characterization of highly translationally and rotationally excited CO fragments resulted from the 230 nm photolysis of OCS and acetone, yielding substantially improved values of the rotational constants for the B state (v'' = 0) of the CO molecule.

Roaming dynamics in acetone dissociation.

DC slice imaging has been employed to study the photodissociation dynamics of acetone at 230 nm, with detection of the CO photoproduct via the B (v' = 0) (1)Sigma(+) <-- X (v'' = 0) (1)Sigma(+) transition. A bimodal translational energy distribution observed in the CO fragments points to two distinct dissociation pathways in the 230 nm photolysis of acetone. One pathway results in substantial translational energy release (E(ave) approximately 0.

The permanent electric dipole moments and magnetic g factors of uranium monoxide.

Permanent electric dipole moments and magnetic g factors for uranium monoxide (UO) have been determined from analyses of optical Stark and Zeeman spectra recorded at a spectral resolution that approaches the natural linewidth limit. Numerous branch features in the previously characterized [L. A.

Probing the electronic structure of UO+ with high-resolution photoelectron spectroscopy.

The pulsed field ionization-zero kinetic energy photoelectron technique has been used to observe the low-lying energy levels of UO+. Rotationally resolved spectra were recorded for the ground state and the first nine electronically excited states. Extensive vibrational progressions were characterized.

Spectroscopy of the ground and low-lying excited states of ThO+.

The ThO(+) cation is of interest as it is a useful prototype for experimental and theoretical studies of bonding in a simple actinide compound. Formally the ground state of ThO(+) has the configuration Th(3+)(7s)O(2-), where there is a single unpaired electron associated with a closed-shell Th(4+)-ion core. The first tier of excited states above the X (2)Sigma(+) ground state is expected to be 1 (2)Delta, 1 (2)Pi, and 2 (2)Sigma(+) derived from the Th(3+)(6d)O(2-) configuration.

Ionization energy measurements and electronic spectra for ThO.

The ionization energy (IE) for ThO has been determined using photoionization efficiency and mass-analyzed threshold ionization measurements. An IE of 6.6038(12) eV was obtained, which was appreciably higher than the result from previous appearance potential measurements [6.

Electronic spectroscopy and ionization potential of UO2 in the gas phase.

The electronic spectroscopy of UO(2) has been examined using multiphoton ionization with mass-selected detection of the UO(2) (+) ions. Supersonic jet cooling was used to reduce the spectral congestion. Twenty-two vibronic bands of neutral UO(2) were observed in the range from 17,400 to 32,000 cm(-1).

Accurate ionization potentials for UO and UO2: a rigorous test of relativistic quantum chemistry calculations.

Accurate ionization potential (IP) measurements provide essential thermodynamic information and benchmark data that can be used to evaluate the validity of electronic structure models. Calculations of the first IP of UO2 using relativistic methods consistently predict values that are approximately 0.7 eV higher than the accepted experimental value.