Understanding and Countering Illumination-Sensitive Dark Current: Toward Organic Photodetectors with Reliable High Detectivity.

Continuously enhanced photoresponsivity and suppressed dark/noise current combinatorially lead to the recent development of high-detectivity organic photodetectors with broadband sensing competence. Despite the achievements, reliable photosensing enabled by organic photodetectors (OPDs) still faces challenges. Herein, we call for heed over a universal phenomenon of detrimental sensitivity of dark current to illumination history in high-performance inverted OPDs.

Phase Stability and Diffusion in Lateral Heterostructures of Methyl Ammonium Lead Halide Perovskites.

Mixed halide hybrid organic-inorganic perovskites have band gaps that span the visible spectrum making them candidates for optoelectronic devices. Transport of the halide atoms in methyl ammonium lead iodide (MAPbI) and its alloys with bromine has been observed in both dark and under illumination. While halide transport upon application of electric fields has received much attention, less is known regarding bromide and iodide interdiffusion down concentration gradients.

Transplantation effects of dental pulp-derived cells on peripheral nerve regeneration in crushed sciatic nerve injury.

The effects of transplanted human dental pulp-derived cells (DPCs) on peripheral nerve regeneration were studied in a rat model of sciatic nerve crush injury. In one group, DPCs were transplanted into the compression site (cell transplantation group); the control group underwent no transplantation (crushed group). Sciatic nerve regeneration was determined based on the recovery of motor function and histological and immunohistochemical analyses.

A Case of Bisphosphonate-Related Osteonecrosis of the Jaw in a Patient with Subpontic Osseous Hyperplasia.

Subpontic osseous hyperplasia (SOH) is a growth of bone occurring on the edentulous ridge beneath the pontics of fixed partial dentures (FPDs). This report describes a case of bisphosphonate- (BP-) related osteonecrosis of the jaw (BRONJ) in a SOH patient followed by deciduation of the bony lesion. A 73-year-old woman visited a dental clinic after experiencing pain and swelling beneath the pontics of a FPD that had been inserted 15 years ago.

Trophic Effects of Dental Pulp Stem Cells on Schwann Cells in Peripheral Nerve Regeneration.

Recently, mesenchymal stem cells have demonstrated a potential for neurotrophy and neurodifferentiation. We have recently isolated mobilized dental pulp stem cells (MDPSCs) using granulocyte-colony stimulating factor (G-CSF) gradient, which has high neurotrophic/angiogenic potential. The aim of this study is to investigate the effects of MDPSC transplantation on peripheral nerve regeneration.

Suppression of HOMO-LUMO transition in a twist form of oligo(phenyleneethynylene) clamped by a right-handed helical peptide.

A donor-π-acceptor (D-π-A) system of oligo(phenyleneethynylene) (OPE) was twisted by clamping both ends of the OPE with a right-handed helical peptide (SSA8=OPE). The induced twist in OPE was in a right-handed way. SSA8=OPE showed a weaker HOMO-LUMO band in the absorption spectrum than that of a reference compound AcOPE without the helix bridge.

Ultra-long-range electron transfer through a self-assembled monolayer on gold composed of 120-Å-long α-helices.

Electron transfer through α-helices has attracted much attention from the viewpoints of their contributions to efficient long-range electron transfer occurring in biological systems and their utility as molecular-electronics elements. In this study, we synthesized a long 80mer helical peptide carrying a redox-active ferrocene unit at the terminal and immobilized the helical peptide on a gold surface. The molecular length is calculated to be 134 Å, in which the helix accounts for 120 Å.

Dipole effects on molecular and electronic structures in a novel conjugate of oligo(phenyleneethynylene) and helical peptide.

A novel conjugate of a helical nonapeptide and an oligo(phenyleneethynylene) (OPE) having a nitro group at a molecular terminal was synthesized. Both components have a dipole. The peptide has a disulfide group at the N-terminal for immobilization on gold.

Chirally twisted oligo(phenyleneethynylene) by cyclization with alpha-helical peptide.

A novel cyclic conjugate of a helical decapeptide and oligo(phenyleneethynylene) (OPE), C-OPE10, was synthesized. The conformation and the optical properties of the cyclic conjugate were studied by circular dichroism (CD), absorption, and emission spectroscopies. In the cyclic conjugate, the rotational motion around the molecular axis of the OPE moiety was hindered to take a chirally twisted conformation, which is a distorted form from the coplanar conjugated structure, as revealed by observation of an induced negative Cotton effect of the OPE moiety.