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<jats:p>A badly weathered column of hieroglyphs was discovered in November 1995 on the side of Stela 1 from La Mojarra in southern Veracruz, Mexico. Most of the signs in this column have now been identified by nighttime examination under artificial lighting, making possible a nearly complete transcription and translation of this column. This data expands the modest corpus of epi-Olmec hieroglyphic texts and confirms various aspects of the decipherment of the epi-Olmec script.</jats:p>

<jats:p> Simple transition-metal complexes of the formula Cp*M(CO) <jats:sub> <jats:italic>n</jats:italic> </jats:sub> BR <jats:sub>2</jats:sub> [Cp* = C <jats:sub>5</jats:sub> (CH <jats:sub>3</jats:sub> ) <jats:sub>5</jats:sub> ] containing an electrophilic, covalently bound main-group ligand react with alkanes and release products resulting from selective functionalization of an alkane at the terminal position. These reactions produce alkylboronate esters, which are common reagents in organic synthesis. Thus, the boryl complexes are rare chemical reagents that react selectivity at the terminal position of an alkane to provide simple functionalized products. Mechanistic analysis shows that ligand dissociation is induced photochemically and that thermal reaction of the resulting intermediate occurs with alkanes. </jats:p>

<jats:p>Understanding of the magnetocrystalline anisotropy in magnetic materials (the influence of different elemental components on the direction of easy magnetization) can be greatly enhanced by measuring the orbital moment anisotropy of the elemental constituents. A circular x-ray dichroism technique is presented that allows the determination of the microscopic origin of the spin reorientation transition in ultrathin single-crystalline cobalt/nickel films. The stronger anisotropy contribution of a much thinner cobalt layer redirects the easy magnetization direction of the entire film.</jats:p>

<jats:p>Narrow spectral features in ocean sediment records offer strong evidence that the cycles of glaciation were driven by astronomical forces. Two million years ago, the cycles match the 41,000-year period of Earth's obliquity. This supports the Croll/Milankovitch theory, which attributes the cycles to variations in insolation. But for the past million years, the spectrum is dominated by a single 100,000-year feature and is a poor match to the predictions of insolation models. The spectrum can be accounted for by a theory that derives the cycles of glaciation from variations in the inclination of Earth's orbital plane.</jats:p>

<jats:p>The compressional wave velocity in molten iron containing 5 percent nickel and 10 percent sulfur increased with increasing temperature. This anomalous behavior was determined to be attributable to the presence of sulfur, which conditions the formation of large molecular units in the liquid. Temperature-induced breakup of macromolecular units resulted in greater packing efficiency and an increased velocity. Ten percent sulfur increased attenuation by one to two orders of magnitude compared with liquid iron. Such behavior at outer core pressures and temperatures would constrain the velocity gradient in the outer core and would enable the discrimination of potential light alloying elements.</jats:p>

<jats:p> BOB.1/OBF.1 is a transcriptional coactivator that is constitutively expressed in B cells and interacts with the Oct1 and Oct2 transcription factors. Upon activation of Jurkat T cells and primary murine thymocytes with phorbol esters and ionomycin, BOB.1/OBF.1 expression and transactivation function were induced. BOB.1/OBF.1 was phosphorylated at Ser <jats:sup>184</jats:sup> both in vivo and in vitro, and this modification was required for inducible activation. Mutation of Ser <jats:sup>184</jats:sup> also diminished transactivation function in B cells, suggesting that the activating phosphorylation that is inducible in T cells is constitutively present in B cells. Thus, BOB.1/OBF.1 is a transcriptional coactivator that is critically regulated by posttranslational modifications to mediate cell type–specific gene expression. </jats:p>

<jats:p>Structural changes in the extracellular matrix are necessary for cell migration during tissue remodeling and tumor invasion. Specific cleavage of laminin-5 (Ln-5) by matrix metalloprotease–2 (MMP2) was shown to induce migration of breast epithelial cells. MMP2 cleaved the Ln-5 γ2 subunit at residue 587, exposing a putative cryptic promigratory site on Ln-5 that triggers cell motility. This altered form of Ln-5 is found in tumors and in tissues undergoing remodeling, but not in quiescent tissues. Cleavage of Ln-5 by MMP2 and the resulting activation of the Ln-5 cryptic site may provide new targets for modulation of tumor cell invasion and tissue remodeling.</jats:p>

<jats:p> Niemann-Pick type C (NP-C) disease, a fatal neurovisceral disorder, is characterized by lysosomal accumulation of low density lipoprotein (LDL)–derived cholesterol. By positional cloning methods, a gene ( <jats:italic>NPC1)</jats:italic> with insertion, deletion, and missense mutations has been identified in NP-C patients. Transfection of NP-C fibroblasts with wild-type <jats:italic>NPC1</jats:italic> cDNA resulted in correction of their excessive lysosomal storage of LDL cholesterol, thereby defining the critical role of NPC1 in regulation of intracellular cholesterol trafficking. The 1278–amino acid NPC1 protein has sequence similarity to the morphogen receptor PATCHED and the putative sterol-sensing regions of SREBP cleavage-activating protein (SCAP) and 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase. </jats:p>

<jats:p> An integrated human-mouse positional candidate approach was used to identify the gene responsible for the phenotypes observed in a mouse model of Niemann-Pick type C (NP-C) disease. The predicted murine NPC1 protein has sequence homology to the putative transmembrane domains of the Hedgehog signaling molecule Patched, to the cholesterol-sensing regions of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and SREBP cleavage-activating protein (SCAP), and to the NPC1 orthologs identified in human, the nematode <jats:italic>Caenorhabditis elegans</jats:italic> , and the yeast <jats:italic>Saccharomyces cerevisiae</jats:italic> . The mouse model may provide an important resource for studying the role of NPC1 in cholesterol homeostasis and neurodegeneration and for assessing the efficacy of new drugs for NP-C disease. </jats:p>

<jats:p> Novel lignin is formed in a mutant loblolly pine ( <jats:italic>Pinus taeda</jats:italic> L.) severely depleted in cinnamyl alcohol dehydrogenase (E.C. 1.1.1.195), which converts coniferaldehyde to coniferyl alcohol, the primary lignin precursor in pines. Dihydroconiferyl alcohol, a monomer not normally associated with the lignin biosynthetic pathway, is the major component of the mutant's lignin, accounting for ∼30 percent (versus ∼3 percent in normal pine) of the units. The level of aldehydes, including new 2-methoxybenzaldehydes, is also increased. The mutant pines grew normally indicating that, even within a species, extensive variations in lignin composition need not disrupt the essential functions of lignin. </jats:p>