Neutron Moderation in the Oklo Natural Reactor and the Time Variation of alpha

In the analysis of the Oklo (gabon) natural reactor to test for a possible time variation of the fine structure constant alpha, a Maxwell-Boltzmann low energy neutron spectrum was assumed. We present here an analysis where a more realistic spectrum is employed and show that the most recent isotopic analysis of samples implies a non-zero change in alpha, over the last two billion years since the reactor was operating, of \Delta\alpha/\alpha\geq 4.5\times 10^{-8} (6\sigma confidence). Issues regarding the interpretation of the shifts of the low energy neutron resonances are discussed.Comment: 7 pages, 4 figures; version 2 included reference to Flambaum/Shuryak work and corrects error in abstract version three corrects a few points and adds discussion on hydrogen and impurity concentration

Mammalian Homolog of Drosophila Tumor Suppressor Lethal (2) Giant Larvae Interacts with Basolateral Exocytic Machinery in Madin-Darby Canine Kidney Cells

The Drosophila tumor suppressor protein lethal (2) giant larvae [l(2)gl] is involved in the establishment of epithelial cell polarity during development. Recently, a yeast homolog of the protein has been shown to interact with components of the post-Golgi exocytic machinery and to regulate a late step in protein secretion. Herein, we characterize a mammalian homolog of l(2)gl, called Mlgl, in the epithelial cell line Madin-Darby canine kidney (MDCK). Consistent with a role in cell polarity, Mlgl redistributes from a cytoplasmic localization to the lateral membrane after contact-naive MDCK cells make cell-cell contacts and establish a polarized phenotype. Phosphorylation within a highly conserved region of Mlgl is required to restrict the protein to the lateral domain, because a recombinant phospho-mutant is distributed in a nonpolar manner. Membrane-bound Mlgl from MDCK cell lysates was coimmunoprecipitated with syntaxin 4, a component of the exocytic machinery at the basolateral membrane, but not with other plasma membrane soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins that are either absent from or not restricted to the basolateral membrane domain. These data suggest that Mlgl contributes to apico-basolateral polarity by regulating basolateral exocytosis

An empirical assessment of the cross-national measurement validity of graded paired comparisons

Contains fulltext : 111992.pdf (publisher's version ) (Closed access)14 p