Use of Mixed CH_3−/HC(O)CH_2CH_2−Si(111) Functionality to Control Interfacial Chemical and Electronic Properties During the Atomic-Layer Deposition of Ultrathin Oxides on Si(111)

Silicon surfaces terminated with a mixed monolayer containing both a propyl aldehyde functionality and methyl groups were prepared and used to control the interfacial chemical and electronic properties of Si(111) surfaces during atomiclayer deposition (ALD) of Al_2O_3 or MnO. Si(111) surfaces functionalized only with the aldehyde moiety exhibited surface recombination velocities, S, of 2500 ± 600 cm s^(−1) whereas the mixed CH_3−/HC(O)CH_2CH_2−Si(111) surfaces displayed S = 25 ± 7 cm s^(−1). During the ALD growth of either Al_2O_3 or MnO, both the HC(O)CH_2CH_2−Si(111) and CH_3−/HC(O)CH_2CH_2−Si(111) surfaces produced increased metal oxide deposition at low cycle number, relative to H−Si(111) or CH_3−Si(111) surfaces. As detected by X-ray photoelectron spectroscopy after the ALD process, the CH_3− and mixed CH_3−/HC(O)CH_2CH_2− functionalized Si(111) surfaces exhibited less interfacial SiO_x than was observed for ALD of metal oxides on H−Si(111) substrates

A Case of Pulmonary Langerhans' Cell Histiocytosis Mimicking Hematogenous Pulmonary Metastases

A 31-year-old man presented with a dry cough and exertional dyspnea. The chest X-ray showed multiple nodular opacities throughout the entire lung field. Chest computed tomography (CT) revealed variable-sized nodules with a peribronchiolar or centrilobular distribution, some of which revealed thick-walled cavitary change. Based on the chest CT findings, it was initially assumed that metastatic lung nodules with hematogenous spread were present; therefore, we performed an open lung biopsy. On microscopic examination, several compact cellular interstitial infiltrates composed of Langerhans' cells, eosinophils, and lymphocytes were observed. Immunochemically, the Langerhans' cells showed strong cytoplasmic staining for S-100 protein. Based on these findings, the patient was diagnosed with Langerhans' cell histiocytosis of the lung. High-resolution CT of the chest is a useful, sensitive tool in the diagnosis of pulmonary Langerhans' cell histiocytosis (PLCH). A typical radiologic finding of PLCH is irregularly shaped cysts. The radiological finding in this case of nodular opacities throughout the lung fields only without cysts is rare in PLCH. We report a case of PLCH with atypical multiple nodules mimicking hematogenous metastatic lung nodules

Mechanisms of Aging and the Preventive Effects of Resveratrol on Age-Related Diseases

Aging gradually decreases cellular biological functions and increases the risk of age-related diseases. Cancer, type 2 diabetes mellitus, cardiovascular disease, and neurological disorders are commonly classified as age-related diseases that can affect the lifespan and health of individuals. Aging is a complicated and sophisticated biological process involving damage to biochemical macromolecules including DNA, proteins, and cellular organelles such as mitochondria. Aging causes multiple alterations in biological processes including energy metabolism and nutrient sensing, thus reducing cell proliferation and causing cellular senescence. Among the polyphenolic phytochemicals, resveratrol is believed to reduce the negative effects of the aging process through its multiple biological activities. Resveratrol increases the lifespan of several model organisms by regulating oxidative stress, energy metabolism, nutrient sensing, and epigenetics, primarily by activating sirtuin 1. This review summarizes the most important biological mechanisms of aging, and the ability of resveratrol to prevent age-related diseases

Use of Mixed CH₃–/HC(O)CH₂CH₂–Si(111) Functionality to Control Interfacial Chemical and Electronic Properties During the Atomic-Layer Deposition of Ultrathin Oxides on Si(111)

Silicon surfaces terminated with a mixed monolayer containing both a propyl aldehyde functionality and methyl groups were prepared and used to control the interfacial chemical and electronic properties of Si(111) surfaces during atomic-layer deposition (ALD) of Al₂O₃ or MnO. Si(111) surfaces functionalized only with the aldehyde moiety exhibited surface recombination velocities, <i>S</i>, of 2500 ± 600 cm s^–1 whereas the mixed CH₃–/HC­(O)­CH₂CH₂–Si­(111) surfaces displayed <i>S</i> = 25 ± 7 cm s^–1. During the ALD growth of either Al₂O₃ or MnO, both the HC­(O)­CH₂CH₂–Si­(111) and CH₃–/HC­(O)­CH₂CH₂–Si­(111) surfaces produced increased metal oxide deposition at low cycle number, relative to H–Si(111) or CH₃–Si­(111) surfaces. As detected by X-ray photoelectron spectroscopy after the ALD process, the CH₃– and mixed CH₃–/HC­(O)­CH₂CH₂– functionalized Si(111) surfaces exhibited less interfacial SiO_<i>x</i> than was observed for ALD of metal oxides on H–Si(111) substrates

Simultaneous Etching and Doping by Cu-Stabilizing Agent for High-Performance Graphene-Based Transparent Electrodes

Cu etching is one of the key processes to produce large-area graphene through chemical vapor deposition (CVD), which is needed to remove Cu catalysts and transfer graphene onto target substrates for further applications. However, the Cu etching method has been much less studied compared to doping or transfer processes despite its importance in producing higher quality graphene films. The Cu etchant generally includes a strong oxidizing agent that converts metallic Cu to Cu2+ in a short period of time. Sometimes, the highly concentrated Cu2+ causes a side reaction leading to defect formation on graphene, which heeds to be suppressed for higher graphene quality. Here we report that the addition of metal-chelating agents such as benzimidazole (BI) to etching solution reduces the reactivity of Cu-etching solution by forming a coordination compound between BI and Cu2+. The resulting graphene film prepared by Cu stabilizing agent exhibits a sheet resistance as lows as similar to 200 Ohm/sq without additional doping processes. We also confirmed that such strong doping effect is stable enough to last for more than 10 months under ambient conditions due to the barrier properties of graphene covering the BI dopants, in contrast to the poor stability of graphene additionally doped by strong p-dopant such as HAuCl4. Thus, we expect that this simultaneous doping and etching method would be very useful for simple and high-throughput production of large-area graphene electrodes with enhanced conductivity

Simultaneous Etching and Doping by Cu-Stabilizing Agent for High-Performance Graphene-Based Transparent Electrodes

Cu etching is one of the key processes to produce large-area graphene through chemical vapor deposition (CVD), which is needed to remove Cu catalysts and transfer graphene onto target substrates for further applications. However, the Cu etching method has been much less studied compared to doping or transfer processes despite its importance in producing higher quality graphene films. The Cu etchant generally includes a strong oxidizing agent that converts metallic Cu to Cu²⁺ in a short period of time. Sometimes, the highly concentrated Cu²⁺ causes a side reaction leading to defect formation on graphene, which needs to be suppressed for higher graphene quality. Here we report that the addition of metal-chelating agents such as benzimidazole (BI) to etching solution reduces the reactivity of Cu-etching solution by forming a coordination compound between BI and Cu²⁺. The resulting graphene film prepared by Cu stabilizing agent exhibits a sheet resistance as lows as ∼200 Ohm/sq without additional doping processes. We also confirmed that such strong doping effect is stable enough to last for more than 10 months under ambient conditions due to the barrier properties of graphene covering the BI dopants, in contrast to the poor stability of graphene additionally doped by strong p-dopant such as HAuCl₄. Thus, we expect that this simultaneous doping and etching method would be very useful for simple and high-throughput production of large-area graphene electrodes with enhanced conductivity

Bone morphogenetic protein-2 as a novel biomarker for refractory chronic rhinosinusitis with nasal polyps

Background: Bone morphogenetic proteins (BMPs), which are members of the TGF-beta superfamily, regulate bone remodeling by stimulating osteoblasts and osteoclasts. Although the association between osteitis and poor surgical outcomes is well known in patients with chronic rhinosinusitis (CRS), BMPs have not been fully investigated as potential biomarkers for the prognosis of CRS. Objective: Our aim was to investigate the role of BMPs in osteitis in patients with CRS with nasal polyps (NPs) (CRSwNPs), as well as associations between BMPs and inflammatory markers in sinonasal tissues from patients with CRSwNP. Methods: We investigated the expression of 6 BMPs (BMP-2, BMP-4, BMP-6, BMP-7, BMP-9, and BMP-10) and their cellular origins in NPs of human subjects by using immunohistochemistry and ELISA of NP tissues. Exploratory factor analysis was performed to identify associations between BMPs and inflammatory markers. Air-liquid interface cell culture of human nasal epithelial cells was performed to evaluate the induction of the epithelial-mesenchymal transition by BMPs. Results: Of the 6 BMPs studied, BMP-2 and BMP-7 were associated with refractoriness. Only BMP-2 concentrations were higher in patients with severe osteitis and advanced disease extent according to the computed tomography findings. Eosinophils and some macrophages were identified as cellular sources of BMP-2 in immunofluorescence analysis. An in vitro experiment revealed that BMP-2 induced epithelialmesenchymal transition in air-liquid interface-cultured human nasal epithelial cells, particularly in a T(H)2 milieu. Conclusion: BMP-2 could reflect the pathophysiology of mucosa and bone remodeling and may be a novel biomarker for refractory CRSwNP.N

Simultaneous Etching and Doping by Cu-Stabilizing Agent for High-Performance Graphene-Based Transparent Electrodes

Cu etching is one of the key processes to produce large-area graphene through chemical vapor deposition (CVD), which is needed to remove Cu catalysts and transfer graphene onto target substrates for further applications. However, the Cu etching method has been much less studied compared to doping or transfer processes despite its importance in producing higher quality graphene films. The Cu etchant generally includes a strong oxidizing agent that converts metallic Cu to Cu2+ in a short period of time. Sometimes, the highly concentrated Cu2+ causes a side reaction leading to defect formation on graphene, which heeds to be suppressed for higher graphene quality. Here we report that the addition of metal-chelating agents such as benzimidazole (BI) to etching solution reduces the reactivity of Cu-etching solution by forming a coordination compound between BI and Cu2+. The resulting graphene film prepared by Cu stabilizing agent exhibits a sheet resistance as lows as similar to 200 Ohm/sq without additional doping processes. We also confirmed that such strong doping effect is stable enough to last for more than 10 months under ambient conditions due to the barrier properties of graphene covering the BI dopants, in contrast to the poor stability of graphene additionally doped by strong p-dopant such as HAuCl4. Thus, we expect that this simultaneous doping and etching method would be very useful for simple and high-throughput production of large-area graphene electrodes with enhanced conductivity.N