C-terminal processing of yeast Spt7 occurs in the absence of functional SAGA complex

Background  

Spt7 is an integral component of the multi-subunit SAGA complex that is required for the expression of ~10% of yeast genes. Two forms of Spt7 have been identified, the second of which is truncated at its C-terminus and found in the SAGA-like (SLIK) complex.     

The role of alkane dithiols in controlling polymer crystallization in small band gap polymer:Fullerene solar cells

The effect of the addition of 1,8‐octanedithiol (ODT) during processing on the microstructure of blend films of poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene)‐alt‐4,7(2,1,3‐benzothiadiazole)] (PCPDTBT) and [6,6]‐phenyl‐C₇₁ butyric acid methyl ester ([70]PCBM) is studied. Grazing incidence X‐ray diffraction and absorption spectroscopy show that the crystalline order of PCPDTBT increases when ODT is introduced in the solution phase either to neat polymer systems or to blends with [70]PCBM. The increased crystalline order is accompanied by less dispersive hole transport in the polymer, and leads to a more efficient formation of a percolating fullerene network within the blend. This contributes to an increase in photocurrent generation. However, the bimolecular recombination rate as determined from photovoltage transients increases upon addition of ODT, limiting the power conversion efficiency to values well below those expected from the energy levels of PCPDTBT. We propose some explanations for this increase in bimolecular recombination, based also on variable angle spectroscopic ellipsometry measurements. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011