Novel LRP6 Mutations Causing Non-Syndromic Oligodontia

The process of tooth formation is a series of reciprocal interactions between the ectoderm and mesoderm, and it is believed that many genetic factors are involved in this complex process. More than a dozen genes have been identified in non-syndromic tooth agenesis; however, the genetic etiology underlying tooth agenesis is not fully understood yet. In this study, we identified two novel LRP6 mutations in two non-syndromic oligodontia families. Both probands had 16 and 17 missing teeth in their permanent dentition. Mutational analysis identified a de novo frameshift mutation by a 1-bp insertion in exon 9 (NM_002336.2: c.1870dupA, p.(Met624Asnfs*29)) and a splicing donor site mutation in intron 8 (c.1762+2T>C). An in vitro splicing assay confirmed the deletion of exon 8, and the deletion would result in a frameshift. Due to the premature termination codons introduced by the frameshift, both mutant transcripts would be degraded by nonsense-mediated mRNA decay, resulting in haploinsufficiency.N

Layer-modulated synthesis of uniform tungsten disulfide nanosheet using gas-phase precursors

The synthesis of layered transition-metal-disulfide (MS2, M = Mo, W) nanosheets with layer controllability and large-area uniformity is an essential requirement for their application in electronic and optical devices. In this report, we describe a synthesis process of WS2 nanosheets with layer controllability and high uniformity using chemical vapor deposition (CVD) and WCl6 and H2S as gas-phase precursors. Through this process, we can systematically modulate the thickness of WS2 nanosheets by controlling the duration of the reaction between WCl6 and H2S. The CVD-grown WS2 nanosheets exhibit good stoichiometry as well as dependencies of a clear Raman shift and bandgap on the number of layers. These properties are confirmed by X-ray photoemission spectroscopy, Raman spectroscopy, and photo-luminescence measurements. The number of layers of WS2 nanosheets is confirmed by atomic force microscopy. Finally, we demonstrate the fabrication and performance of a photodetector based on a hybrid structure consisting of graphene and a WS2 nanosheet

Nitrogen-doped ZnO/n-Si core-shell nanowire photodiode prepared by atomic layer deposition

Photodiodes made from core-shell nanowires (NWs) comprising n-type silicon (n-Si; core) and nitrogen-doped ZnO (ZnO:N; shell) were fabricated by atomic layer deposition of ZnO:N on vertically aligned Si Wis. The device properties were investigated as functions of nitrogen content of the ZnO:N shell. The electron-carrier concentration of ZnO:N was modulated by adjusting the concentration of the reactant, diluted ammonium hydroxide, from 0 to 30%. The rectification ratio and the reverse-current density of the ZnO:Nin-Si planar heterojunction were evaluated under dark condition for various NH4OH concentrations. The ZnO:N/n-Si heterojunction prepared with NH4OH 15% was found to have the lowest reverse-current density with a moderate resistivity. In order to realize an effective ZnO:N/n-Si photodiode, a ZnO:N layer prepared with 15% NH4OH was deposited on well-aligned Si nanowires. The core-shell NW photodiode showed more sensitive photodetecting performance in UV light than the planar photodiode. Also, the significantly enhanced performances of the core-shell NW photodiode were evaluated by examining its spectral responsivity. (C) 2015 Elsevier Ltd. All rights reserved

Layer-Controlled, Wafer-Scale, and Conformal Synthesis of Tungsten Disulfide Nanosheets Using Atomic Layer Deposition

The synthesis of atomically thin transition-metal disulfides (MS2) with layer controllability and large-area uniformity is an essential requirement for their application in electronic and optical devices. In this work, we describe a process for the synthesis of WS2 nanosheets through the sulfurization of an atomic layer deposition (AID) WO, film with systematic layer controllability and wafer-level uniformity. The X-ray photoemission spectroscopy, Raman, and photoluminescence measurements exhibit that the AID-based WS2 nanosheets have good stoichiometry, clear Raman shift, and bandgap dependence as a function of the number of layers. The electron mobility of the monolayer WS2 measured using a field-effect transistor (FET) with a high-k dielectric gate insulator is shown to be better than that of CVD-grown WS2, and the subthreshold swing is comparable to that of an exfoliated MoS2 FET device. Moreover, by utilizing the high conformality of the AID process, we have developed a process for the fabrication of WS2 nanotubes

Layer-Controlled, Wafer-Scale, and Conformal Synthesis of Tungsten Disulfide Nanosheets Using Atomic Layer Deposition

The synthesis of atomically thin transition-metal disulfides (MS₂) with layer controllability and large-area uniformity is an essential requirement for their application in electronic and optical devices. In this work, we describe a process for the synthesis of WS₂ nanosheets through the sulfurization of an atomic layer deposition (ALD) WO₃ film with systematic layer controllability and wafer-level uniformity. The X-ray photoemission spectroscopy, Raman, and photoluminescence measurements exhibit that the ALD-based WS₂ nanosheets have good stoichiometry, clear Raman shift, and bandgap dependence as a function of the number of layers. The electron mobility of the monolayer WS₂ measured using a field-effect transistor (FET) with a high-k dielectric gate insulator is shown to be better than that of CVD-grown WS₂, and the subthreshold swing is comparable to that of an exfoliated MoS₂ FET device. Moreover, by utilizing the high conformality of the ALD process, we have developed a process for the fabrication of WS₂ nanotubes