Charge-transfer induced surface conductivity for a copper based inorganic-organic hybrid

Inorganic-organic hybrids are receiving increasing attention as they offer the opportunity to combine the robust properties of inorganic materials with the versatility of organic compounds. We have studied the electric properties of an inorganic-organic hybrid with the chemical formula: CuCl4(C6H5CH2CH2NH3)2. This material is a ferromagnetic insulator that can easily be processed from solution. We show that the surface conductivity of the hybrid can be increased by five orders of magnitude by covering the surface with an organic electron donor. This constitutes a novel method to dope perovskite-based materials and study their charge transport properties.

Precise engineering of quantum dot array coupling through their barrier widths

Quantum dots are known to confine electrons within their structure. Whenever they periodically aggregate into arrays and cooperative interactions arise, novel quantum properties suitable for technological applications show up. Control over the potential barriers existing between neighboring quantum dots is therefore essential to alter their mutual crosstalk. Here we show that precise engineering of the barrier width can be experimentally achieved on surfaces by a single atom substitution in a haloaromatic compound, which in turn tunes the confinement properties through the degree of quantum dot intercoupling. We achieved this by generating self-assembled molecular nanoporous networks that confine the twodimensional electron gas present at the surface. Indeed, these extended arrays form up on bulk surface and thin silver films alike, maintaining their overall interdot coupling. These findings pave the way to reach full control over two-dimensional electron gases by means of self-assembled molecular networks

Bent-Shaped p-Type Small-Molecule Organic Semiconductors: A Molecular Design Strategy for Next-Generation Practical Applications

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CAGE Basic/Analysis Databases: the CAGE resource for comprehensive promoter analysis

Cap-analysis gene expression (CAGE) Basic and Analysis Databases store an original resource produced by CAGE, which measures expression levels of transcription starting sites by sequencing large amounts of transcript 5′ ends, termed CAGE tags. Millions of human and mouse high-quality CAGE tags derived from different conditions in >20 tissues consisting of >250 RNA samples are essential for identification of novel promoters and promoter characterization in the aspect of expression profile. CAGE Basic Database is a primary database of the CAGE resource, RNA samples, CAGE libraries, CAGE clone and tag sequences and so on. CAGE Analysis Database stores promoter related information, such as counts of related transcripts, CpG islands and conserved genome region. It also provides expression profiles at base pair and promoter levels. Both databases are based on the same framework, CAGE tag starting sites, tag clusters for defining promoters and transcriptional units (TUs). Their associations and TU attributes are available to find promoters of interest. These databases were provided for Functional Annotation Of Mouse 3 (FANTOM3), an international collaboration research project focusing on expanding the transcriptome and subsequent analyses. Now access is free for all users through the World Wide Web at

High Performance Oxygen-bridged N-shaped Semiconductors with Stabilized Crystal Phase and Blue Luminescence

Here, we describe an oxygen-bridged N-shaped π-electron core, dinaphtho[2,3-d:2\u27,3\u27-d"]benzo[1,2-b:4,5-b\u27]difuran (DNBDF), as a new entity of organic semiconducting materials. Interestingly, by introduction of flexible alkyl chains at appropriate positions, DNBDF π-cores exhibit solution processability, a highly stabilized crystal phase, high mobility, and blue luminescence as a solid.平成26年度関西大学若手研究者育成経費JSPS科学研究費補助金　若手研究(B)(No.25810118)JSPS科学研究費補助金　基盤研究(C)(No.26410254)JSPS科学研究費補助金　基盤研究(B)(No.25288091

Charge mobility calculation of organic semiconductors without use of experimental single-crystal data

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Sub-molecular structural relaxation at a physisorbed interface with monolayer organic single-crystal semiconductors

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Differential Use of Signal Peptides and Membrane Domains Is a Common Occurrence in the Protein Output of Transcriptional Units

Membrane organization describes the orientation of a protein with respect to the membrane and can be determined by the presence, or absence, and organization within the protein sequence of two features: endoplasmic reticulum signal peptides and alpha-helical transmembrane domains. These features allow protein sequences to be classified into one of five membrane organization categories: soluble intracellular proteins, soluble secreted proteins, type I membrane proteins, type II membrane proteins, and multi-spanning membrane proteins. Generation of protein isoforms with variable membrane organizations can change a protein's subcellular localization or association with the membrane. Application of MemO, a membrane organization annotation pipeline, to the FANTOM3 Isoform Protein Sequence mouse protein set revealed that within the 8,032 transcriptional units (TUs) with multiple protein isoforms, 573 had variation in their use of signal peptides, 1,527 had variation in their use of transmembrane domains, and 615 generated protein isoforms from distinct membrane organization classes. The mechanisms underlying these transcript variations were analyzed. While TUs were identified encoding all pairwise combinations of membrane organization categories, the most common was conversion of membrane proteins to soluble proteins. Observed within our high-confidence set were 156 TUs predicted to generate both extracellular soluble and membrane proteins, and 217 TUs generating both intracellular soluble and membrane proteins. The differential use of endoplasmic reticulum signal peptides and transmembrane domains is a common occurrence within the variable protein output of TUs. The generation of protein isoforms that are targeted to multiple subcellular locations represents a major functional consequence of transcript variation within the mouse transcriptome

Broadening of Distribution of Trap States in PbS Quantum Dot Field-Effect Transistors with High-k Dielectrics

We perform a quantitative analysis of the trap density of states (trap DOS) in PbS quantum dot field-effect transistors (QD-FETs), which utilize several polymer gate insulators with a wide range of dielectric constants. With increasing gate dielectric constant, we observe increasing trap DOS close to the lowest unoccupied molecular orbital (LUMO) of the QDs. In addition, this increase is also consistently followed by broadening of the trap DOS. We rationalize that the increase and broadening of the spectral trap distribution originate from dipolar disorder as well as polaronic interactions, which are appearing at strong dielectric polarization. Interestingly, the increased polaron-induced traps do not show any negative effect on the charge carrier mobility in our QD devices at the highest applied gate voltage, giving the possibility to fabricate efficient low-voltage QD devices without suppressing carrier transport