Discovery of a new long-lived isomeric state in 125Ce

A new long-lived isomeric state in the near proton dripline nucleus ¹²⁵Ce has been identified with Schottky mass spectrometry at GSI. The excitation energy E ^* = 103(12)keV and the decay time of 193(1)s have been obtained from a single stored fully ionized ^125m Ce⁵⁸⁺ ion. The data implies an E3 transition and a 1/2⁺ assignment for the spin of the isomer.     

Polarized light and X-ray precession study of the ferroelastic domains of YBa2Cu3O7-δ

The ferroelastic domains of the orthorhombic phase of YBa₂Cu₃O_7- have been observed in polarized light on ceramics and single crystals. By combining polarized light microscopy with the X-ray precession technique, the correlation of the orientation of the orthorhombica- andb-axes with that of thea-b-plane bireflectance, reflection dichroism, transmission dichroism (at a thickness of about 1m), reflection tints generated with compensators and upon uncrossing of polars, as well as the orientation of etch pits has been realized on ferroelastic single domains, bi-domains and more complicated domain patterns. Four ferroelastic orthorhombic domain states have been identified, at variance with former group theoretical considerations, predicting only two states. Ensembles of lamellar domains beyond optical resolution generate strong bireflectance with principal axes rotated by 45° relative to the truea, b-directions.     

Bioremediation of petroleum hydrocarbons in soil column lysimeters from Kwajalein Island

Applied Biochemistry and Biotechnology - Soil column studies were used to evaluate petroleum hydrocarbon (PHC) remediation in soils from Kwajalein Atoll. Treatments included controls, and...     

Role of Cell Surface Lipopolysaccharides in Escherichia coli K12 adhesion and transport

The influence of bacterial surface lipopolysaccharides (LPS) on cell transport and adhesion has been examined by use of three mutants of Escherichia coli K12 with well-characterized LPS of different lengths and molecular composition. Two experimental techniques, a packed-bed column and a radial stagnation point flow system, were employed to investigate bacterial adhesion kinetics onto quartz surfaces over a wide range of solution ionic strengths. Although the two systems capture distinct deposition (adhesion) mechanisms because of their different hydrodynamics, similar deposition kinetics trends were observed for each bacterial strain. Bacterial deposition rates were directly related to the electrostatic double layer interaction between the bacteria and quartz surfaces, in qualitative agreement with classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. However, DLVO theory does not fully explain the deposition behavior for the bacterial strain with the lengthy, uncharged O-antigen portion of the LPS. Neither the length nor the charge characteristics of the LPS molecule directly correlated to deposition kinetics, suggesting a complex combination of cell surface charge heterogeneity and LPS composition controls the bacterial adhesive characteristics. It is further suggested that bacterial deposition behavior is determined by the combined influence of DLVO interactions, LPS-associated chemical interactions, and the hydrodynamics of the deposition system.