Mutations at the flightless-I locus (flit) of Drosophila melanogaster cause flightiessness or, when severe, incomplete ceilularization during early embryogenesis, with subsequent abnormalities in mesoderm invagination and in gastrulation. After chromosome walking, deficiency mapping, and transgenic analysis, we have isolated and characterized Oightless-I cDNAs, enabling prediction of the complete amino acid sequence of the 1256-residue protein. Data base searches revealed a homologous gene in Caenorhabditis ekgans, and we have isolated and characterized corresponding cDNAs. By using the polymerase chain reaction with nested sets of degenerate oligonucleotide primers based on conserved regions of the C. elegans and D. melanogaster proteins, we have doned a homologous human cDNA. The predicted C. ekgans and human proteins are, respectively, 49% and 58% identical to the D. melanogaster protein. The predicted proteins have signifilcant sequence similarity to the actin-binding protein gelsolin and related proteins and, in addition, have an N-terminal domain consisting of a repetitive amphipathic leucine-rich motif. This repeat is found in D. melanogaster, Saccharomyces cerevisiae, and mammalian proteins known to be involved in cell adhesion and in binding to other proteins. The structure of the maternally expressed flightless-I protein suggests that it may play a key role in embryonic cellularization by interacting with both the cytoskeleton and other cellular components. The presence of a highly conserved homologue in nematodes, flies, and humans is indicative of a fundamental role for this protein in many metazoans.

This paper reports the external quantum efficiency (EQE) of encapsulated screen-printed crystalline silicon solar cells, where the encapsulation includes a layer of luminescent down-shifting (LDS) molecules. At wavelengths less than 400 nm, the inclusion of the LDS molecules increases the EQE from near zero to, at most, 40%. The increase in EQE corresponds to a rise in short-circuit current density of 0Á37 W 0Á13 mA/cm 2 under the AM1-5g spectrum.

Certain gene mutations in Drosophila melanogaster cause sluggish motor activity. We have localized the

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The absorption coefficient α(λ) of polydimethylsiloxane (PDMS) silicone and ethylene vinyl acetate (EVA) is monitored during exposure to damp‐heat (DH) and UV accelerated aging tests. In the DH test, the samples were exposed to 85% relative humidity at 85°C for 1325 h, satisfying the DH components of the IEC, UL, and IEEE's humidity‐freeze and DH tests. It is shown that moisture introduced by the DH exposure scatters incident light, reducing transmission through test samples and complicating optical experiments. It was therefore necessary to dry out the samples to assess the effect of DH exposure on α(λ). By this procedure, it was found that DH exposure caused an increase of α(λ) in both PDMS and EVA, where small absorption shoulders were introduced at wavelengths of 250–500 nm; this translates to a 0.14% and 0.39% loss in module efficiency for the silicone and EVA, respectively. The weight gain due to moisture was 0.035% for PDMS and 0.28% for EVA. In the UV test, the samples were held at 60 ± 5°C and exposed to 52 kWh/m2 between the wavelengths of 280 and 385 nm, and 5.0 kWh/m2 between 280 and 320 nm, satisfying the pre‐conditioning UV tests of the IEC reliability standard. The UV exposure did not affect α(λ) of either the PDMS or the EVA. Copyright © 2010 John Wiley & Sons, Ltd.