A new type of a-Si/c-Si heterojunction solar cell, called the HIT (Heterojunction with Intrinsic Thin-layer) solar cell, has been developed based on ACJ (Artificially Constructed Junction) technology. A conversion efficiency of more than 18% has been achieved, which is the highest ever value for solar cells in which the junction was fabricated at a low temperature (<200°C).

All the iron-based superconductors identified to date share a square lattice composed of Fe atoms as a common feature, despite having different crystal structures. In copper-based materials, the superconducting phase emerges not only in square lattice structures but also in ladder structures. Yet iron-based superconductors without a square lattice motif have not been found despite being actively sought out. Here, we report the discovery of pressure-induced superconductivity in the iron-based spin-ladder material BaFe 2 S 3 , a Mott insulator with striped-type magnetic ordering below ~120 K. On the application of pressure this compound exhibits a metal-insulator transition at about 11 GPa, followed by the appearance of superconductivity below T c = 14 K, right after the onset of the metallic phase. Our findings indicate that iron-based ladder compounds represent promising material platforms, in particular for studying the fundamentals of iron-based superconductivity.The discovery of iron-based superconductors had a significant impact on condensed matter physics and led to extensive study of the interplay between crystal structure, magnetism and superconductivity 1 . All the iron-based superconducting materials discovered to date share the same structural motif: a two-dimensional square lattice formed by edge-shared FeX 4 tetrahedra (X = Se, P and As). The Fe atoms are nominally divalent in most of the parent materials. These parent compounds undergo a magnetic transition at low temperatures, typically exhibiting striped-type ordering.Superconductivity appears when the magnetic order is fully suppressed by the application of pressure or by the addition of doping carriers through chemical Purpose of this studyThe application of pressure is often a useful means of changing the electronic structure of a compound so as to induce a metallic state without simultaneously introducing any degree of disorder 17 . In this study, we investigated in detail the magnetic properties of a sulphur-analogue of the Fe-based ladder materials, BaFe 2 S 3 (space group: orthorhombic, Cmcm) 18,19 , and undertook experimental trials in which this compound was subjected to high pressures to obtain the metallic state. The electronic properties of this material depend on the manner in which the samples are synthesized, and thus we present data for sample 1 describing magnetic properties, and data for a range of samples 1 to 6 describing high-pressure effects. The details of the sample preparation process are given in the Method section. Electronic properties under ambient pressureFigure 2a displays the temperature dependence of the electrical resistivity (ρ) of BaFe 2 S 3 along the leg direction under ambient pressure. The observed insulating behaviour, which occurs despite the expected metallic behaviour in an unfilled 3d manifold, is caused by the Coulomb repulsion between Fe 3d electrons, which becomes prominent in a quasi-one-dimensional ladder structure. Figure 2b shows the magnetic susceptibility (χ) at 5 T along the three orthorhombic...

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Thin flakes of titanium dioxide have been synthesized through a novel route via exfoliation of a layered precursor. A protonic oxide of H x Ti2- x /4□ x /4O4·H2O (x ∼ 0.7; □, vacancy) was delaminated into colloidal single sheets (thickness 0.75 nm) by being interacted with a bulky organic amine, (C4H9)4NOH. The resulting titania sol was freeze-dried to produce a gel in a thin filmlike texture. The gelation took place by reassembling 10−20 titanate sheets and consequently yielding lamellar aggregates. Upon heating above 400 °C, the gel was transformed into titanium dioxide (anatase) in thin flaky morphology (20−30 nm in thickness versus ∼μm in the lateral dimension). Intermediates at various stages of the synthetic process as well as the final product were examined by applying various characterization techniques such as X-ray diffraction (XRD), scanning and transmission electron microscopes (SEM, TEM), FT-IR and Raman spectroscopies, thermogravimetry, and elemental analysis. The flaky particulates were aggregated in a disordered fashion to make an open microstructure. Nitrogen gas physisorption measurements revealed that the material was meso- to macroporous having a BET surface area of 40−110 m2 g-1. Photocatalytic activity for the material was demonstrated for a degradation reaction of aqueous trichloroethylene.

The electronics fields face serious problems associated with electric power; these include the development of ecologically friendly power-generation systems and ultralow-power-consuming circuits. Moreover, there is a demand for developing new power-transmission methods in the imminent era of ambient electronics, in which a multitude of electronic devices such as sensor networks will be used in our daily life to enhance security, safety and convenience. We constructed a sheet-type wireless power-transmission system by using state-of-the-art printing technologies using advanced electronic functional inks. This became possible owing to recent progress in organic semiconductor technologies; the diversity of chemical syntheses and processes on organic materials has led to a new class of organic semiconductors, dielectric layers and metals with excellent electronic functionalities. The new system directly drives electronic devices by transmitting power of the order of tens of watts without connectors, thereby providing an easy-to-use and reliable power source. As all of the components are manufactured on plastic films, it is easy to place the wireless power-transmission sheet over desks, floors, walls and any other location imaginable.

Macroautophagy is an evolutionarily conserved catabolic mechanism that delivers intracellular constituents to lysosomes using autophagosomes. To achieve degradation, lysosomes must fuse with closed autophagosomes. We previously reported that the soluble -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein syntaxin (STX) 17 translocates to autophagosomes to mediate fusion with lysosomes. In this study, we report an additional mechanism. We found that autophagosome-lysosome fusion is retained to some extent even in knockout (KO) HeLa cells. By screening other human SNAREs, we identified YKT6 as a novel autophagosomal SNARE protein. Depletion of YKT6 inhibited autophagosome-lysosome fusion partially in wild-type and completely in KO cells, suggesting that YKT6 and STX17 are independently required for fusion. YKT6 formed a SNARE complex with SNAP29 and lysosomal STX7, both of which are required for autophagosomal fusion. Recruitment of YKT6 to autophagosomes depends on its N-terminal longin domain but not on the C-terminal palmitoylation and farnesylation that are essential for its Golgi localization. These findings suggest that two independent SNARE complexes mediate autophagosome-lysosome fusion.

In human mitochondria, the AUA codon encodes methionine via a mitochondrial transfer RNA for methionine (mt-tRNA(Met)) that contains 5-formylcytidine (f(5)C) at the first position of the anticodon (position 34). f(5)C34 is required for deciphering the AUA codon during protein synthesis. Until now, the biogenesis and physiological role of f(5)C34 were unknown. We demonstrate that biogenesis of f(5)C34 is initiated by S-adenosylmethionine (AdoMet)-dependent methylation catalyzed by NSUN3, a putative methyltransferase in mitochondria. NSUN3-knockout cells showed strong reduction in mitochondrial protein synthesis and reduced oxygen consumption, leading to deficient mitochondrial activity. We reconstituted formation of 5-methylcytidine (m(5)C) at position 34 (m(5)C34) on mt-tRNA(Met) with recombinant NSUN3 in the presence of AdoMet, demonstrating that NSUN3-mediated m(5)C34 formation initiates f(5)C34 biogenesis. We also found two disease-associated point mutations in mt-tRNA(Met) that impaired m(5)C34 formation by NSUN3, indicating that a lack of f(5)C34 has pathological consequences.

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