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A major challenge in the development of novel devices in nano and molecular electronics is their interconnection with larger-scale electrical circuits required to control and characterize their functional properties. Local electrical probing by multiple probes with ultimate scanning tunneling microscopy (STM) precision can significantly improve efficiency in analyzing individual nano-electronic devices without the need for full electrical integration. [ABSTRACT FROM PUBLISHER]

Methionine sulphoxide reductase maintains adhesin function during oxidative stress. Using Streptococcus gordonii as a model, we now show the mechanistic basis of adhesin maintenance provided by MsrA. In biofilms, S. gordonii selectively expresses the msrA gene. When the wild-type strain was grown with exogenous hydrogen peroxide (HO), msrA-specific mRNA expression significantly increased, while acid production was unaffected. In the presence of HO, a msrA-deletion mutant (ΔMsrA) showed a 6 h delay in lag phase growth, a 30% lower yield of HO, significantly greater inhibition by HO on agar plates (reversed by complementation), 30% less adhesion to saliva-coated hydroxyapatite, 87% less biofilm formation and an altered electrophoretic pattern of SspAB protein adhesins. Using mass spectrometry, methionine residues in the Met-rich central region of SspB were shown to be oxidized by HO and reduced by MsrA. In intact wild-type cells, MsrA colocalized with a cell wall-staining dye, and MsrA was detected in both cell wall and cytosolic fractions. To maintain normal adhesion and biofilm function of S. gordonii in response to exogenous oxidants therefore msrA is upregulated, methionine oxidation of adhesins and perhaps other proteins is reversed, and adhesion and biofilm formation is maintained. [ABSTRACT FROM AUTHOR]

Describes the moderate resolution imaging spectroradiometer (MODIS) radiometric calibration product (level 1B) in connection with the thermal emissive and reflective solar bands. Production of a band-integrated radiance and reflectance factor product for all measurements; Identification of specific sensor design characteristics; Summarization of the product file format.

A mode-locked picosecond laser has been used to prebunch electron beams at a photocathode. These electrons are subsequently accelerated through coupling structures and microwaves radiated. The relation between the microwave output and the properties of the picosecond pulse train and the electron beam output coupling process are reported and related to theory. Among the important attributes of these devices are their ability to generate almost arbitrary microwave waveforms, to operate in the 100–200 kV region with very simple power supplies and excellent spectral purity, and to generate substantially more microwave power than contained in the optical drive. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Development of a HIV-1 Vaccine Using an Orally-Administered, Replication-Competent Adenovirus Serotype 4 Vector Expressing Env Clade C Glycoprotein," by J. Alexander and colleagues is presented.