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Intrinsic silicon (Si) is forbidden for infrared (IR) sensing at the communication wavelength like 1.31 or 1.55 µm due to the well‐known bandgap limitation. In this work, an unexpected physical picture of using argon (Ar) is identified, which is usually inert to the surrounding chemical environment and used as a protective agent in semiconductor processing, to overcome the IR‐sensing‐forbidden problem in Si. Here, it is shown by an analysis of a dynamic secondary ion mass spectrometer that such a Si, when exposed to laser pulse in Ar gas, can contain a very high dose of Ar up to 1020 cm−3 even after 1300 days. First‐principles calculations, molecular dynamics, and Hall effect measurements reveal that, due to both steric and dynamic repulsions by Ar orbitals to Si dangling bonds, the Ar‐filled‐vacancy produces a much wider defect band inside the gap, which is not only responsible for strong infrared absorption, but also causes a significant increase in n‐type conductivity, both in line with experiments. The study proves that originally inert elements in fact can act as active impurities in semiconductors for advanced applications, which updates the current knowledge of defect physics. [ABSTRACT FROM AUTHOR]

With the evolution of the human species, the mandibular third molars have varying degrees of impaction, and the impaction process will cause irreversible damage such as damage to the adjacent teeth. At the same time, there are serious intraoperative and postoperative complications in the extraction of impacted teeth. Whether the mandibular third molar is impacted or not, it may appear in the tooth germ stage. This article showed a case of routine mandibular third molar germ extraction and aims to discuss the analysis of the third molar angulation, retromolar space, crown width, root development, and other factors through the panoramic tomography taken during the tooth germ period and predict the possibility of third molar impaction. At the same time, according to the predicted results, preventive tooth germ extraction or scientific management of tooth germs for the highly likely impacted molars. Compared with fully mature impacted teeth, tooth germ extraction can reduce the difficulty of surgery and reduce trauma. [ABSTRACT FROM AUTHOR]

Background and Purpose: Tooth eruption is a complicated process regulated by the dental follicles (DF). Our recent study discovered that tooth eruption was inhibited upon injection of bleomycin into DF. However, the mechanisms were unknown.Experimental Approach: Human dental follicle cells (hDFCs) were treated by bleomycin or exogenous TGF-β1 or transfected by plasmids loading SMAD7 or shRNA targeting SMAD7, followed by osteogenesis induction assay and signalling analysis. Human fresh DF tissues and Wistar rats were used to further confirm bleomycin function.Key Results: Bleomycin decreased expression of RUNX2 and osteogenic genes in hDFCs, reducing osteogenic capacity. TGF-β1 expression was up-regulated in bleomycin-treated hDFCs. The effects of exogenous TGF-β1 were similar to those of bleomycin in hDFCs. Additionally, compared to SMAD2/3, SMAD7 expression increased more in bleomycin- or TGF-β1-treated hDFCs. Overexpression of SMAD7 likewise significantly decreased RUNX2 expression and osteogenic capacity of hDFCs. Knockdown of SMAD7 markedly attenuated the inhibitory effects of bleomycin and TGF-β1 on osteogenic capacity and RUNX2 expression of hDFCs. Most importantly, changes in TGF-β1, SMAD7, and RUNX2 expressions were similar in the DF of rats and humans treated with bleomycin.Conclusion and Implications: SMAD7 was a negative regulator of osteogenic differentiation in DFCs through suppressing RUNX2 expression. Bleomycin or TGF-β1 inhibited osteogenic differentiation of DFCs via a TGF-β1/SMAD7/RUNX2 pathway. Our findings might be beneficial for enhancing the osteogenic activity of DFCs or inhibiting the eruption of undesirable teeth. [ABSTRACT FROM AUTHOR]

The regular micrometer-scale triangular arrays were formed using ultrafast femtosecond laser irradiation on (111) surface of silicon wafer immersed in KOH solution (0.1 g/ml). At low laser fluence, the resulting surface is covered by triangular pits microstructures, whereas at high laser fluence, the structures are transformed to multilayer-triangular stacks-microstructures. The number of triangular stacks layer increased as the laser fluence increased. The formation of triangle microstructure arrays depends on both silicon surface crystallographic orientation and the concentration of KOH solution. Either for lower KOH solution concentration (0.02 g/ml) or other silicon crystallographic orientation, triangle arrays cannot be obtained. We attribute the formation of triangular microstructure arrays to the laser-assisted chemical etching process. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The presence of non-cutaneous vascular lesions in the syndrome of multiple enchondromas and subcutaneous hemangiomas, also named Maffucci syndrome, is exceedingly rare. Until now, non-cutaneous vascular lesions have been described in nine patients, while only three cases were present in the oral cavity; they were found in the tongue in two patients and in the lower lip in one patient. Herein, we report the second case of vascular lesions localized in the mucosa of lower lip in a patient with Maffucci syndrome. Histopathologic examination showed spindle cell hemangioma. [ABSTRACT FROM AUTHOR]