Theory of chromatography and its application to cation exchange in soils.

Different types of solutions of the differential equation describing the process of cation exchange chromatography are compared and evaluated for their applicability to soil conditions. In cases where divalent cations replace monovalent ions, the exchange front assumes a stationary profile at an early stage which then yields an analytical solution provided a fairly simple exchange equation like that of Gapon or Vanselow is applicable. Where monovalent ions replace divalent ions, a non-stationary front arises, which is strongly dominated by the exchange equation. A good approximation of the front can be obtained by an analytical solution taking no account of diffusion or dispersion. Knowledge of the total electrolyte in the soil column is often the limiting factor in predicting the location and shape of the exchange front.[112.23.07]. (Abstract retrieved from CAB Abstracts by CABI’s permission

Archaeal Hel308 helicase targets replication forks in vivo and in vitro and unwinds lagging strands

Mutations in mammalian and Drosophila Hel308 and PolQ paralogues cause genome instability but their helicase functions are mysterious. By in vivo and in vitro analysis, we show that Hel308 from archaea (Hel308a) may act at stalled replication forks. Introducing hel308a into Escherichia coli dnaE strains that conditionally accumulate stalled forks caused synthetic lethality, an effect indistinguishable from E.coli RecQ. Further analysis in vivo indicated that the effect of hel308a is exerted independently of homologous recombination. The minimal biochemical properties of Hel308a protein were the same as human Hel308. We describe how helicase actions of Hel308a at fork structures lead specifically to displacement of lagging strands. The invading strand of D-loops is also targeted. Using archaeal Hel308, we propose models of action for the helicase domain of PolQ, promoting loading of the translesion polymerase domain. We speculate that removal of lagging strands at stalled forks by Hel308 promotes the formation of initiation zones, priming restart of lagging strand synthesis

Earth matter density uncertainty in atmospheric neutrino oscillations

That muon neutrinos $\nu_{\mu}$ oscillating into the mixture of tau neutrinos $\nu_{\tau}$ and sterile neutrinos $\nu_{s}$ has been studied to explain the atmospheric $\nu_{\mu}$ disappearance. In this scenario, the effect of Earth matter is a key to determine the fraction of $\nu_{s}$. Considering that the Earth matter density has uncertainty and this uncertainty has significant effects in some neutrino oscillation cases, such as the CP violation in very long baseline neutrino oscillations and the day-night asymmetry for solar neutrinos, we study the effects caused by this uncertainty in the above atmospheric $\nu_{\mu}$ oscillation scenario. We find that this uncertainty seems to have no significant effects and that the previous fitting results need not to be modified fortunately.Comment: 7 pages, 1 figure, to appear in Phys. Rev.

The cosmic X-ray experiment aboard HEAO-1

The HEAO-1 A-2 experiment, designed to study the large scale structure of the galaxy and the universe at X-ray energies is described. The instrument consists of six gas proportional counters of three types nominally covering the energy ranges of 0.15-3 keV, 1.2-20 keV, and 2.5-60 keV. The two low energy detectors have about 400 sq cm open area each while the four others have about 800 sq cm each. Dual field of view collimators allow the unambiguous determination of instrument internal background and diffuse X-ray brightness. Instrument characteristics and early performance are discussed

VIGILANCE OF NESTING WHOOPING CRANES IN JUNEAU COUNTY, WISCONSIN

Vigilance plays an important role in the detection of possible threats and reducing the risk of predation, including during the incubation period. We examined the visual vigilance of incubating whooping cranes (Grus americana) in Juneau County, Wisconsin, during the 2019 nesting season. We deployed 9 trail cameras and tagged crane presence and behavior in 32,801 photos which were used in our analysis. We assessed individual nest and environmental variables and their effects on vigilant behavior of incubating cranes using linear mixed-models. Vigilant behavior was defined by a posture in which the crane’s head was up, neck was erect, and bill was horizontal to the ground. Nesting whooping cranes were less vigilant during the night (x̄ = 14.3 ± 1.4% [SE]) than during the day (25.0 ± 0.7%), and cranes were less vigilant during precipitation events. Cranes nesting closer to closed forest were 11-12% less vigilant than those nesting at medium or far distances from forest. Lastly, cranes nesting in medium-sized wetlands were 4-5% more vigilant than cranes in small or large wetlands. Further research to determine if levels of vigilance affect nest success could help increase productivity for this population

Multiple-crystal X-ray topographic characterization of periodically domain-inverted KTiOPO4 crystal

A periodically domain-inverted KTiOPO4 crystal has been characterized for the first time by multiple-crystal multiple-reflection x-ray topography. The striation contrast within the domain- inverted regions has been revealed in high strain-sensitivity reflection topographs. The origin of formation of the striation contrast and the mechanism of domain inversion in KTiOPO4 are discussed in terms of the structural characteristics of KTiOPO4