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We investigated a range of different mesoporous NiO electrodes prepared by different research groups and private firms in Europe to determine the parameters which influence good quality photoelectrochemical devices. This benchmarking study aims to solve some of the discrepancies in the literature regarding the performance of p-DSCs due to differences in the quality of the device fabrication. The information obtained will lay the foundation for future photocatalytic systems based on sensitized NiO so that new dyes and catalysts can be tested with a standardized material. The textural and electrochemical properties of the semiconducting material are key to the performance of photocathodes. We found that both commercial and non-commercial NiO gave promising solar cell and water-splitting devices. The NiO samples which had the two highest solar cell efficiency (0.145% and 0.089%) also gave the best overall theoretical H2 conversion.

Donor-π-acceptor photosensitizers for NiO photocathodes that exhibit a broad spectral response across the visible region are presented. These enabled an increase in the photocurrent density of p-type dye-sensitized solar cells to 8.2 mA cm(-2) and a tandem cell to be assembled which generated a photocurrent density of 5.15 mA cm(-2).

Meiotic drivers are parasitic loci that force their own transmission into greater than half of the offspring of a heterozygote. Many drivers have been identified, but their molecular mechanisms are largely unknown. The wtf4 gene is a meiotic driver in Schizosaccharomyces pombe that uses a poison-antidote mechanism to selectively kill meiotic products (spores) that do not inherit wtf4. Here, we show that the Wtf4 proteins can function outside of gametogenesis and in a distantly related species, Saccharomyces cerevisiae. The Wtf4poison protein forms dispersed, toxic aggregates. The Wtf4antidote can co-assemble with the Wtf4poison and promote its trafficking to vacuoles. We show that neutralization of the Wtf4poison requires both co-assembly with the Wtf4antidote and aggregate trafficking, as mutations that disrupt either of these processes result in cell death in the presence of the Wtf4 proteins. This work reveals that wtf parasites can exploit protein aggregate management pathways to selectively destroy spores.

The collision dynamics of He single ionization by 3.6 MeV/u Se 28ϩ impact was explored using the reaction microscope of the Gesellschaft für Schwerionenforschung, a high-resolution integrated multielectron recoil-ion momentum spectrometer. The complete three-particle final-state momentum distribution ͑nine Cartesian components p i ͒ was imaged with a resolution of ⌬p i ϷϮ0.1 a.u. by measuring the three momentum components of the emitted electron and the recoiling target ion in coincidence. The projectile energy loss has been determined on a level of ⌬E p /E p Ϸ10 Ϫ7 and projectile scattering angles as small as ⌬Ϸ10 Ϫ7 rad became accessible. The experimental data which are compared with results of classical trajectory Monte Carlo calculations reveal an unprecedented insight into the details of the electron emission and the collision dynamics for ionization of helium by fast heavy-ion impact.

Differential coordination of growth and patterning across metazoans gives rise to a diversity of sizes and shapes at tissue, organ, and organismal levels. While tissue size and tissue function can be interdependent 1-5 , mechanisms coordinating size and function remain poorly understood. Planarians are regenerative flatworms that bi-directionally scale their adult body size 6,7 and asexually reproduce, via transverse fission, in a size-dependent manner 8-10. This paradigm offers a robust context to address the gap in knowledge underlying the link between size and function. A novel planarian fission protocol revealed that progeny number and fission initiation frequency scale with parent size. Fission progeny size is fixed by previously unidentified mechanically vulnerable planes spaced at an absolute distance along the anterior-posterior (A/P) axis. An RNAi screen of A/P patterning genes uncovered TGFβ and Wnt signaling components as regulators of fission initiation frequency rather than fission plane position. Finally, inhibition of Wnt and TGFβ signaling during growth altered the patterning of mechanosensory neurons, a neural sub-population that is distributed in accordance with animal size and modulates fission behavior. Therefore, our study identifies a novel role for TGFβ and Wnt in regulating size-dependent behavior, uncovering an interdependence between patterning, growth, and neurological function. The infrequency of planarian fission behavior has largely precluded its mechanistic dissection. However, recently optimized animal husbandry techniques augmented fission activity 11-12 , permitting us to study the integration of animal size with fission behavior. Large planaria from recirculation culture exhibited robust and reproducible increases in fission activity when transitioned to static culture and starved (Fig. 1a, Video S1). Live imaging provided detailed characterization of the fission process. Planarians first elongate and adhere their posterior tissue to a substrate. Next, periodic body contractions concentrate body mass towards the head region while thinning out tissues immediately anterior to the adherent tail. After 20-40 minutes, progressive stretching ruptures connecting tissue with Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

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