Direct photocurrent mapping of organic solar cells (OSCs) using a novel implementation of a near-field scanning optical microscope (NSOM) is described. By rastering the light output from the NSOM through a semitransparent electrode across the OSC surface, it is possible to collect height and photocurrent images simultaneously with a lateral resolution that is governed by the NSOM aperture. The photocurrent images demonstrate that film inhomogeneities and segregation effects strongly influence OSC device performance.

We have measured the integrated Stokes parameters of the light emitted following the impact excitation by polarized electrons of the np 5 (n+1)p [5/2] We have measured the integrated Stokes parameters of the light emitted following the impact excitation by polarized electrons of the np5 ( n + l)p [5/213 states in Ne (n =2), Ar (n =3), Kr ( n =4), Xe (n = 5 ) , and the np5 (n + 1 )p [5/212 state in Kr. The near-threshold linear-polarization fractions 7, were consistent with zero for all of the J = 3 states measured, providing no evidence of Mott scattering. For J = 2 excitation, 7 , shows the clear influence of the intermediately coupled nature of the state. At threshold, the measured circular polarization 77, and linear polarization 7, for the J =3 states agree well with the LS-coupled threshold predictions. These results provide the basis for optical measurements of electron polarization.

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Data provide strong evidence that surface UV-irradiance reduces long-term systemic folate levels, and that this is influenced by the C677T-MTHFR gene variant. We speculate this effect may be due to 677TT-MTHFR individuals containing more 5,10CH -H PteGlu, and that this folate form may be particularly UV labile. Since UV-irradiance lowers RCF in an MTHFR genotype-specific way, there are likely implications for human health and the evolution of skin pigmentation.

Solar radiation early in pregnancy interacts with light sensitive vitamins to influence an embryo's genetic profile. This influences both adult disease risk and may play a role in the evolution of skin colour.