2,249 research outputs found
Four-week inhalation toxicity, mutagenicity and immunotoxicity studies of Keum-Yeon-Cho (NosmoQ), tobacco substitute composition, in mice
No full textSafety of Kcum-Yeon-Cho (NosmoQ), a tobacco substitute composition, was evaluated in terms of acute- and 4,weeks repeated-inhalation toxicity, mutagenicity, and immunotoxicity using Balb/e mice. The air inside the inhalation chamber was collected and analyzed by GC-MS. In acute inhalation toxicity test, male and female mice were exposed to 40 Keum-Yeon-Cho cigarettes, The 50% lethal concentration (LC50) of NosmoQ was considered to be much higher than 40 cigarettes in both sexes. In 4-week repeated inhalation toxicity test, male and female mice were exposed for 6 h/day, 5 days/week for 4 weeks to 10 and 20 cigarettes per day, while control mice ere exposed to Filtered air. Our data indicated that no observed adverse effect level (NOAEL) of Keuna-Yeon-Cho should be over 20 cigarettes per day. Results of Salmonella typhimarium reversion assay with/without histidine moiety, in vivo chromosomal aberration and in vivo micronucleus assays using mouse bone marrow cells revealed that Kcum-Yeon-Cho has 110 mutagenicity. Evaluation of peripheral cellular immunity of mice treated with Keum-yeong-Cho using in vitro lymphocyte proliferation assay showed no significant difference in mean stimulation index (SI) between mice exposed to Keum-Yeon-Cho and control mice. Mean CO concentrations and total particulate matter contents of 10 and 20 cigarettes were 21.1 +/- 1.23 and 40.7 +/- 1.21 ppm (mean +/-S.D.. it = 5). and 25.7+/-3.09 and 59.0+/-4.0 mg dry weight (mean +/-S.D., n = 5), respectively. Although at negligible concentration (less than ppb level) several polycyclic aromatic hydrocarbons (PAHs) were also detected, these results indicate that NosmoQ has no toxic effect on mice. (C) 2002 Elsevier Science B.V. All rights reserved.N
Supplemental Material, Suppl_for_CT-1763.R2 - Serum-mediated Activation of Bone Marrow–derived Mesenchymal Stem Cells in Ischemic Stroke Patients: A Novel Preconditioning Method
No full textSupplemental Material, Suppl_for_CT-1763.R2 for Serum-mediated Activation of Bone Marrow–derived Mesenchymal Stem Cells in Ischemic Stroke Patients: A Novel Preconditioning Method by Gyeong Joon Moon, Yeon Hee Cho, Dong Hee Kim, Ji Hee Sung, Jeong Pyo Son, Sooyoon Kim, Jae Min Cha, and Oh Young Bang in Cell Transplantation</p
Supplementary material - Supplemental material for Antioxidant Properties of the Manzamenones from the Tropical Marine Sponge <i>Plakortis</i> sp.
No full textSupplemental material, Supplementary material, for Antioxidant Properties of the Manzamenones from the Tropical Marine Sponge Plakortis sp. by MyoungLae Cho, Yeon-Ju Lee, Jong Seok Lee, Hee-Jae Shin and Hyi-Seung Lee in Natural Product Communications</p
Synthesis of Small-angle Twisted Bilayer Graphene on Atomic-stepped Copper Surface by Chemical Vapor Deposition
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sj-docx-1-tam-10.1177_17588359231189421 – Supplemental material for Pretreatment endocrine symptoms and recurrence-free survival among young premenopausal patients with breast cancer: a prospective cohort study
No full textSupplemental material, sj-docx-1-tam-10.1177_17588359231189421 for Pretreatment endocrine symptoms and recurrence-free survival among young premenopausal patients with breast cancer: a prospective cohort study by Danbee Kang, Juhee Cho, Seri Park, Hyo Jung Kim, Seok Won Kim, Jeong Eon Lee, Jonghan Yu, Se Kyung Lee, Ji-Yeon Kim, Seok Jin Nam and Yeon Hee Park in Therapeutic Advances in Medical Oncology</p
sj-docx-1-cno-10.1177_2329048X231210421 - Supplemental material for A Case of Multiple Mitochondrial Dysfunctions Syndrome 4 with Novel <i>ISCA2</i> Variants, Mimicking Post-Infectious Encephalitis
No full textSupplemental material, sj-docx-1-cno-10.1177_2329048X231210421 for A Case of Multiple Mitochondrial Dysfunctions Syndrome 4 with Novel ISCA2 Variants, Mimicking Post-Infectious Encephalitis by Hyungjin Chin, MD, Jaeso Cho, MD, Woo Joong Kim, MD, Soo Yeon Kim, MD, Byung Chan Lim, MD, Ki Joong Kim, MD, PhD and Jong Hee Chae, MD, PhD in Child Neurology Open</p
Low noise high performance 50nm T-gate metamorphic HEMT with cut-off frequency f<sub>T</sub> of 440 GHz for millimeterwave imaging receivers applications
No full textThe 50 nm m-HEMT exhibits extremely high f<sub>T</sub>, of 440GHz, low F<sub>min</sub> of 0.7 dB, associated gain of 13 dB at 26 GHz with an exceptionally high Id of 200 mA/mm and gm of 950 ms/mm at low noise biased point
Rotation of Graphene on Cu during Chemical Vapor Deposition and Its Application to Control the Stacking Angle of Bilayer Graphene
No full text© 2022 American Chemical Society. All rights reserved.Control of the stacking angle (θS) of bilayer graphene (BLG) is essential for fundamental studies and applications of BLG. Especially, the use of chemical vapor deposition (CVD) to grow high-quality BLG requires this control, but methods to achieve it are not available. Here, we found that graphene rotates during the CVD process, and this action can be exploited as a new strategy to control θS. The rotation of graphene was revealed by the population changes of AB-stacked BLG and 30°-twisted BLG upon the growth time change; this change can only be explained by rotation of graphene. The rotation is largely affected by the edge state of graphene which can be tuned by growth temperature. The rotation was observed through experimental results combined with theoretical calculation. The rotation can be blocked or accelerated by controlling the growth temperature, by which highly selective growth of AB-stacked BLG or 30°-twisted BLG can be achieved.11Nsciescopu
Atomic Layer-Modified 3D Pd Nanochannels for High-Performance Hydrogen Sensing
No full textPalladium (Pd), known for its excellent H2 adsorption properties and ability to form palladium hydride (PdH x ), is extensively utilized as a key material in hydrogen (H2) sensing technologies. Nevertheless, conventional Pd-based H2 sensors have shown limited performance enhancements due to challenges in precisely controlling the microscopic interfaces between Pd nanograins, which determine the total resistance signal of the sensors. This limitation arises from the lack of a technique capable of precisely manipulating these interfaces at the atomic level. In this study, we develop an atomic layer etching (ALE) technique to enhance the performance of Pd-based H2 sensors by enabling precise atomic-scale control over the surface of Pd nanochannels. We fabricated 3D Pd nanopatterns with ultrasmall grain sizes through a top-down nanolithography process, followed by an ALE process that achieved atomic-level precision (10 & Aring; resolution) without compromising material crystallinity. Our two-step ALE process, comprising surface modification with Cl2 plasma and removal with NH3 ligand addition, enables uniform etching across a 4 in. wafer with less than 1% variation in etch per cycle (EPC). This atomic-level modulation of Pd nanochannels resulted in significantly enhanced H2 sensitivity, demonstrating a maximum 130-fold increase in response to 1% H2 concentration compared to nonatomically controlled sensors. Such substantial enhancement has been difficult to achieve through conventional structural tuning methods and is attributed to the maximized volume change of PdH x resulting from the expanded gaps between Pd grains. This platform provides a promising avenue for developing high-performance H2 sensors and other noble-metal-based applications requiring atomic-level structural precision.
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