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<jats:p> The current-potential curve at a 2.8-nanometer-radius electrode immersed in a solution containing micromolar concentrations of a redox couple, [(trimethylammonio)methyl] ferrocene (Cp <jats:sub>2</jats:sub> FeTMA <jats:sup>+</jats:sup> )/Cp <jats:sub>2</jats:sub> FeTMA <jats:sup>2+</jats:sup> , shows discrete steps (a coulomb staircase) representing single electron-transfer events. Discrete potential steps are also found in the current-time curve as the electrode potential relaxes back to equilibrium after a coulostatic potential step. </jats:p>

<jats:p>In solution, biopolymers commonly fold into well-defined three-dimensional structures, but only recently has analogous behavior been explored in synthetic chain molecules. An aromatic hydrocarbon backbone is described that spontaneously acquires a stable helical conformation having a large cavity. The chain does not form intramolecular hydrogen bonds, and solvophobic interactions drive the folding transition, which is sensitive to chain length, solvent quality, and temperature.</jats:p>

<jats:p>An 11-mound site in Louisiana predates other known mound complexes with earthen enclosures in North America by 1900 years. Radiometric, luminescence, artifactual, geomorphic, and pedogenic data date the site to over 5000 calendar years before present. Evidence suggests that the site was occupied by hunter-gatherers who seasonally exploited aquatic resources and collected plant species that later became the first domesticates in eastern North America.</jats:p>

<jats:p>Reversible, controllable optical nanocontraction and dilatation in a chalcogenide glass film was induced by polarized light, and a direct correlation of this optomechanical effect with the reversible optical-induced optical anisotropy (dichroism) also exhibited by the chalcogenide glass was observed. A microscopic model of the photoinduced, reversible structural phenomenon responsible for the optomechanical behavior is presented. The ability to induce an anisotropic optomechanical effect could form the basis of a number of applications, including polarized light-dependent optical nanoactuators, optomechanical diaphragm micropumps, and even motors driven by polarized light.</jats:p>

<jats:p>Classical late-infantile neuronal ceroid lipofuscinosis (LINCL) is a fatal neurodegenerative disease whose defective gene has remained elusive. A molecular basis for LINCL was determined with an approach applicable to other lysosomal storage diseases. When the mannose 6-phosphate modification of newly synthesized lysosomal enzymes was used as an affinity marker, a single protein was identified that is absent in LINCL. Sequence comparisons suggest that this protein is a pepstatin-insensitive lysosomal peptidase, and a corresponding enzymatic activity was deficient in LINCL autopsy specimens. Mutations in the gene encoding this protein were identified in LINCL patients but not in normal controls.</jats:p>

<jats:p> Age-related macular degeneration (AMD) is the leading cause of severe central visual impairment among the elderly and is associated both with environmental factors such as smoking and with genetic factors. Here, 167 unrelated AMD patients were screened for alterations in <jats:italic>ABCR</jats:italic> , a gene that encodes a retinal rod photoreceptor protein and is defective in Stargardt disease, a common hereditary form of macular dystrophy. Thirteen different AMD-associated alterations, both deletions and amino acid substitutions, were found in one allele of <jats:italic>ABCR</jats:italic> in 26 patients (16%). Identification of <jats:italic>ABCR</jats:italic> alterations will permit presymptomatic testing of high-risk individuals and may lead to earlier diagnosis of AMD and to new strategies for prevention and therapy. </jats:p>