We have studied the effect of thermal annealing periods on the optoelectrical properties of Mg2Si pn ‐junction diodes fabricated by a conventional thermal diffusion process of Ag acceptor. The Au/Ag/n ‐Mg2Si (carrier concentration = 2 × 1015cm‐3, resistivity = 5‐10 Ωcm) substrate was annealed at 550 °C in the Ar‐atmosphere using a rapid thermal annealing (RTA) furnace. The annealing periods were varied between 2 and 10 minutes. Clear rectifying behavior of J ‐V characteristics was observed for the diodes annealed for more than 2 minutes. Spectral responsivity from the photon energy threshold of approximately 0.6 eV was demonstrated with the Mg2Si pn ‐junction diodes under the zero bias condition at room temperature. The maximum intensity of spectral responsivity was increased with decrease the annealing period. The spectral responsivity of the diode with the RTA periods of 4 minutes was approximately 4 times higher than that of 10 minutes annealed one. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
We have fabricated Mg2Si pn-junction photodiodes with an Au-ring electrode and a SiO2 passivation layer by means of a lift-off photolithography process. Current-voltage (I -V) characteristics of the photodiodes showed obvious rectifying behavior at room temperature. The ideality factor of n determined from the slope of I -V characteristics was 1.76 -1.92. The photodiode showed a photoresponse with threshold energy of approximately 0.6 eV under a zero-bias condition. The intensity of peak photoresponse was improved approximately three times compared with the opaque Au-circular electrode type Mg2Si photodiode previously reported.
The synchondroses in the cranial base are important structures in craniofacial growth, and the spheno-occipital synchondrosis (SOS) is representative of a typical growth site. Endoplasmic reticulum (ER) stress is associated with multiple biological processes and is a critical factor in chondrogenesis. It has been reported that 78kDa Glucose-regulated protein (Grp78) plays an important role in suppressing regulators in ER stress-mediated apoptosis in chondrogenesis, and Cripto is the cell surface signaling partner of Grp78 in the transforming growth factor-β (TGF-β) signaling pathway. We attempt to clarify the immunolocalization of Grp78 and Cripto in the SOS. The mice head at embryonic day 17.5 (E17.5) were collected and embedded in paraffin. The serial sections were stained with hematoxylin and eosin, Alcian blue, lectin, and immunostaining. The SOS structure containing the resting, proliferative, and hypertrophic zone were identified with Alcian blue staining, wheat germ agglutinin, and Type II Collagen immunostaining. Immunostaining of Grp78 in the SOS revealed positive immunoreactivity in all the chondrocytes of the SOS. However, the chondrocytes of the proliferating zone were weakly immunopositive to Cripto, while the chondrocytes of the hypertrophic zone were strongly immunopositive. Since the immunolocalization of Grp78 and Cripto was different in cartilage zone, these data suggest that Grp78 and Cripto would be involved in the regulation of hypertrophic chondrocyte differentiation and may be related with ER stress in the SOS.
OTAWA-KAMOGASHIRA, N.; MATSUDA, Y.; TAKEZAKI, M.; HATAKEYAMA, Y.; TAMAOKI, S. & ISHIKAWA, H.Immunohistochemical study of amelogenin binding proteins in an amelogenin point mutation mouse. Int. J. Morphol., 37(2):522-532, 2019. SUMMARY:Amelogenin is one of the enamel matrices secreted by ameloblasts. A mutation of the amelogenin gene can cause hereditary dental enamel defects known as amelogenesis imperfecta (AI). Since lysosome-associated membrane protein-1 (LAMP-1), -3 (LAMP-3), and 78kDa glucose-related protein (Grp78) were identified as binding proteins of amelogenin, several studies have suggested the involvement of these binding proteins with the cell kinetics of ameloblasts in normal or abnormal conditions. The purpose of this study is to investigate the distribution of these amelogenin binding proteins in the ameloblast cell differentiation of mice with a point mutation of the amelogenin gene (Amelx*). The incisors of Amelx* mice had a white opaque color and the tooth surface was observed to be rough under a scanning electron microscope. Among the sequential ameloblast cell differentiation in the Amelx* mice, the shape of ameloblasts at the transition stage was irregular in comparison to those in wild-type (WT) mice. Immunostaining of Grp78 revealed that the whole cytoplasm of the transition stage ameloblasts was immunopositive for Grp78 antibody, while only the distal part of cell was positive in the WT mice. Furthermore, in the Amelx* mice, the cytoplasm of the transition stage ameloblasts was immunopositive for LAMP-1 and LAMP-3. These results suggest that Amelx* may cause the abnormal distribution of amelogenin binding proteins in the cytoplasm of ameloblasts. KEY WORDS: Amelogenin; Amelogenesis imperfecta; 78kDa glucose-related protein (Grp78); Lysosome-associated membrane proteins (LAMPs). OTAWA-KAMOGASHIRA, N.; MATSUDA, Y.; TAKEZAKI, M.; HATAKEYAMA, Y.; TAMAOKI, S. & ISHIKAWA, H. Immunohistochemical study of amelogenin binding proteins in an amelogenin point mutation mouse. OTAWA-KAMOGASHIRA, N.; MATSUDA, Y.; TAKEZAKI, M.; HATAKEYAMA, Y.; TAMAOKI, S. & ISHIKAWA, H. Immunohistochemical study of amelogenin binding proteins in an amelogenin point mutation mouse. Int. J. Morphol., 37(2):527-537, 2019.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.