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<jats:p>With science and technology (S&amp;T) research increasingly relying on international cooperation, there is a need for U.S. foreign policy to focus on S&amp;T. Large collaborative research efforts, including international space and energy projects and global environmental conventions, are hindered by the U.S. government's lack of commitment, which makes potential partners in Europe and Asia hesitate at joining these projects. The U.S. government has not placed enough importance on international S&amp;T as being integral to the United States' economic and political future.</jats:p>

<jats:p>The implementation of the Government Performance and Results Act, whose aim is to improve the accountability of government-funded programs in the United States, could have far-reaching effects on scientific research. Concerns that the ability to do revolutionary research may be compromised by the increased emphasis on short-term measurable goals are discussed. An alternative strategy that could safeguard the open-ended needs of research and allow appropriate oversight is presented.</jats:p>

<jats:p> Iron-sulfur proteins are found in all life forms. Most frequently, they contain Fe <jats:sub>2</jats:sub> S <jats:sub>2</jats:sub> , Fe <jats:sub>3</jats:sub> S <jats:sub>4</jats:sub> , and Fe <jats:sub>4</jats:sub> S <jats:sub>4</jats:sub> clusters. These modular clusters undergo oxidation-reduction reactions, may be inserted or removed from proteins, can influence protein structure by preferential side chain ligation, and can be interconverted. In addition to their electron transfer function, iron-sulfur clusters act as catalytic centers and sensors of iron and oxygen. Their most common oxidation states are paramagnetic and present significant challenges for understanding the magnetic properties of mixed valence systems. Iron-sulfur clusters now rank with such biological prosthetic groups as hemes and flavins in pervasive occurrence and multiplicity of function. </jats:p>

<jats:p> Single-electron reductions of linked triruthenium clusters of the general type Ru <jats:sub>3</jats:sub> -pyrazine-Ru <jats:sub>3</jats:sub> produced mixed valence systems showing spectroscopic characteristics of rapid intramolecular electron transfer. Reflectance infrared spectroelectrochemistry was used to characterize the vibrational spectra of mixed valence systems that contained one carbon monoxide ligand on each Ru <jats:sub>3</jats:sub> cluster. Infrared spectra in the CO stretching region showed two resolved, partially coalesced, and coalesced ν(CO) bands for clusters with rate constants for intramolecular electron transfer <jats:italic>k</jats:italic> <jats:sub>e</jats:sub> increasing from = 1 × 10 <jats:sup>9</jats:sup> s <jats:sup>–</jats:sup> <jats:sup>1</jats:sup> up to 5 × 10 <jats:sup>11</jats:sup> and 9 × 10 <jats:sup>11</jats:sup> s <jats:sup>–</jats:sup> <jats:sup>1</jats:sup> , respectively. These data provide a strong correlation between rates of intramolecular electron transfer and infrared spectral bandshape. </jats:p>

<jats:p>Recent findings about zonal displacements of the Pacific warm pool required a notable modification of the delayed action oscillator theory, the current leading theory for the El Niño–Southern Oscillation (ENSO). Simulations with a linearized coupled ocean-atmosphere model resulted in 3- to 6-year ENSO-like oscillations, with many of the variable model parameters found to be very close to their observed values. This simple model suggests that ocean processes that are ignored or underestimated in the delayed action oscillator theory, such as zonal current convergence, zonal advection of sea surface temperature, and equatorial wave reflection from the eastern ocean boundary, are fundamental to the development of the ENSO, in particular to its manifestations in the central equatorial Pacific.</jats:p>

<jats:p> Stacks of global seismic data reveal the time and distance dependence of high-frequency (1-hertz) precursors to the seismic phase <jats:italic>PKKP</jats:italic> . Synthetic seismogram modeling shows that scattering from random small-scale topography at the <jats:italic>PKKP</jats:italic> core-mantle <jats:bold>–</jats:bold> boundary reflection point generates precursory arrivals similar to those seen in the data. Models with a root mean square core-mantle–boundary topography of 250 to 350 meters and correlation length of 7 to 10 kilometers explain the main features of the data. However, a systematic range-dependent misfit between observed and predicted precursor power suggests that inner core scattering may contribute to the precursors. </jats:p>

<jats:p>Three source regions show evidence of a low-velocity layer that is less than 15 kilometers thick on top of the core-mantle boundary and require about a 3:1 ratio of shear-to-compressional velocity reduction, which is consistent with partial melt. Layer thickness is correlated with travel time residuals of the seismic phases that are most sensitive to the lowermost mantle velocity. These observations suggest that the layer is thinned beneath downwellings but is present everywhere along the core-mantle boundary. Low viscosity accompanying partial melt can localize the upwelling of warmed mantle, making the low-velocity layer a plausible source of mantle plumes.</jats:p>

<jats:p>The distance dependence of photoinduced electron transfer in duplex DNA was determined for a family of synthetic DNA hairpins in which a stilbene dicarboxamide forms a bridge connecting two oligonucleotide arms. Investigation of the fluorescence and transient absorption spectra of these hairpins established that no photoinduced electron transfer occurs for a hairpin that has six deoxyadenosine-deoxythymidine base pairs. However, the introduction of a single deoxyguanosine-deoxycytidine base pair resulted in distance-dependent fluorescence quenching and the formation of the stilbene anion radical. Kinetic analysis suggests that duplex DNA is somewhat more effective than proteins as a medium for electron transfer but that it does not function as a molecular wire.</jats:p>