96 research outputs found
Charge separation in an acceptor–donor–acceptor triad material with a lamellar structure
Linking covalently both electron donor and acceptor components is an efficient way to gain thermodynamic control over the formation of well-ordered heterojunction materials suitable for organic photovoltaics. In this context, we attached flexible polymer segments to the termini of a (perylene bisimide)–quaterthiophene–(perylene bisimide) triad. The microphase segregation of the resulting coil-rod-coil architecture served to reliably promote the formation of lamellar phases. The lamellae were oriented vertically relative to the substrate, and they could be laterally aligned by mechanical rubbing, as determined by small and wide angle X-ray scattering, transmission electron microscopy, electron diffraction and AFM. Transient absorption spectroscopy revealed that light absorption was followed by charge separation and that charge recombination was slower in thin films than for solution-phase samples, especially when longer side chains were used. Thus, this study is a first step towards reliable lamellar phase segregation in donor–acceptor materials on the route towards improved materials for organic photovoltaics
The ABA-Deficiency Suppressor Locus HAS2 Encodes the PPR Protein LOI1/MEF11 Involved in Mitochondrial RNA Editing
The hot ABA-deficiency suppressor2 (has2) mutation increases drought tolerance and the ABA sensitivity of stomata closure and seed germination. Here we report that the HAS2 locus encodes the MITOCHONDRIAL EDITING FACTOR11 (MEF11), also known as LOVASTATIN INSENSITIVE1. has2/mef11 mutants exhibited phenotypes very similar to the ABA-hypersensitive mutant, hai1-1 pp2ca-1 hab1-1 abi1-2, which is impaired in four genes encoding type 2C protein phosphatases (PP2C) that act as upstream negative regulators of the ABA signaling cascade. Like pp2c, mef11 plants were more resistant to progressive water stress and seed germination was more sensitive to paclobutrazol (a gibberellin biosynthesis inhibitor) as well as mannitol and NaCl, compared with the wild-type plants. Phenotypic alterations in mef11 were associated with the lack of editing of transcripts for the mitochondrial cytochrome c maturation FN2 (ccmFN2) gene, which encodes a cytochrome c-heme lyase subunit involved in cytochrome c biogenesis. Although the abundance of electron transfer chain complexes was not affected, their dysfunction could be deduced from increased respiration and altered production of hydrogen peroxide and nitric oxide in mef11 seeds. As minor defects in mitochondrial respiration affect ABA signaling, this suggests an essential role for ABA in mitochondrial retrograde regulation
New Fused Bis-Thienobenzothienothiophene Copolymers and Their Use in Organic Solar Cells and Transistors
Synthesis of novel thieno[3,2-b]thienobis(silolothiophene) based low bandgap polymers for organic photovoltaics
Stammganglieninfarkte im Kindesalter. Klinisch-neuroradiologische Befunde und Differentialdiagnose
The shuttering brains: Less lateralized and less asymmetric. A combined fMRI and VBM study in shuttering adults
Adult Toxocara canis encephalitis.
A 48-year-old patient with Toxocara canis infection developed severe ataxia, rigor and neuropsychological disturbances. An aetiology was proven by an indirect immunofluorescence test. CT and MRI revealed both diffuse and circumscribed white matter lesions. Angiography showed multiple occlusion of branches of the middle cerebral artery. Anthelminthic treatment was beneficial in the initial stage of the disease, but had no effect on progression of CNS symptoms. Immunosuppressive therapy with prednisolone and azathioprine yielded partial recovery and stabilisation of the patient
Structure-transport property relationships in thieno-thiophene containing donor-acceptor co-polymers
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