259 research outputs found
Hanguk i miguk e jung-yohan iyu / Miguk i hanguk e jung-yohan iyu
No full textFor more about the East-West Center, see http://www.eastwestcenter.org/This project maps the trade, investment, employment, business, diplomacy, security, education, tourism, and people-to-people connections between the United States and South Korea at the national, state, and local levels. Part of the Asia Matters for America initiative, this publication, the one-page summaries for states and congressional districts, and website are resources for understanding the robust and dynamic US-Korea relationship
Hangug-i migug-e jung-yohan iyu / migug-i hangug-e jung-yohan iyu
No full textFor more about the East-West Center, see http://www.eastwestcenter.org/The 4th edition of Korea Matters for America/America Matters for Korea, part of the Asia Matters for America initiative, maps the trade, investment, employment, business, diplomacy, security, education, tourism, and people-to-people connections between the United States and South Korea at the national, state, and local levels. This publication and the AsiaMattersforAmerica.org website are resources for understanding the robust and dynamic US-Indo-Pacific relationship
Integration of Gold Nanoparticle-Carbon Nanotube Composite for Enhanced Contact Lifetime of Microelectromechanical Switches with Very Low Contact Resistance
No full textElectrical circuits require ideal switches with low power consumption for future electronic applications. However, transistors, the most developed electrical switches available currently, have certain fundamental limitations such as increased leakage current and limited subthreshold swing. To overcome these limitations, micromechanical switches have been extensively studied; however, it is challenging to develop micromechanical switches with high endurance and low contact resistance. This study demonstrates highly reliable microelectromechanical switches using nanocomposites. Nanocomposites consisting of gold nanoparticles (Au NPs) and carbon nanotubes (CNTs) are coated on contact electrodes as contact surfaces through a scalable and solution-based fabrication process. While deformable CNTs in the nanocomposite increase the effective contact area under mechanical loads, highly conductive Au NPs provide current paths with low contact resistance between CNTs. Given these advantages, the switches exhibit robust switching operations over 5 x 10(6) cycles under hot-switching conditions in air. The switches also show low contact resistance without subthreshold region, an extremely small leakage current, and a high on/off ratio.
Visible-Light-Induced Organophotocatalytic Difunctionallization: Open-Air Hydroxysulfurization of Aryl Alkenes with Aryl Thiols
No full text© 2022 American Chemical Society. All rights reserved.Herein, we report a regioselective visible-light-induced organophotoredox catalytic difunctionalization method to prepare β-hydroxysulfides using aryl alkenes and aryl thiols as substrates. The reaction provides a wide substrate scope of aryl alkenes (from simple styrene to complex bioactive compounds) and aryl thiols (from diverse heteroaromatic thiols to nonheteroaromatic thiols) (total 45 examples, up to 88% yield). Based on the combined experimental and computational studies, we demonstrate that in situ generated hydroperoxyl radicals from O2 in air react with benzylic radicals, which restrains the reaction between benzylic radicals and the acidic form of thiols in a classical thiol-ene radical reaction. We show that difunctionalization is possible due to the choice of bases, diluted substrate concentrations, increment in catalyst loading, and selection of suitable aryl thiols under aerobic conditions. Considering the biological importance of heteroaromatic thiols and the lack of methods to install them, our approach offers a platform to derive various β-hydroxysulfides that contain aromatic elements.11Nsciescopu
Dyrk1A Phosphorylates p53 and Inhibits Proliferation of Embryonic Neuronal Cells
No full textDown syndrome (DS) is associated with many neural defects, including reduced brain size and impaired neuronal proliferation, highly contributing to the mental retardation. Those typical characteristics of DS are closely associated with a specific gene group "Down syndrome critical region" (DSCR) on human chromosome 21. Here we investigated the molecular mechanisms underlying impaired neuronal proliferation in DS and, more specifically, a regulatory role for dual-specificity tyrosine-(Y) phosphorylation-regulated kinase 1A (Dyrk1A), a DSCR gene product, in embryonic neuronal cell proliferation. We found that Dyrk1A phosphorylates p53 at Ser-15 in vitro and in immortalized rat embryonic hippocampal progenitor H19-7 cells. In addition, Dyrk1A-induced p53 phosphorylation at Ser-15 led to a robust induction of p53 target genes (e. g. p21(CIP1)) and impaired G(1)/G(0)-S phase transition, resulting in attenuated proliferation of H19-7 cells and human embryonic stem cell-derived neural precursor cells. Moreover, the point mutation of p53-Ser-15 to alanine rescued the inhibitory effect of Dyrk1A on neuronal proliferation. Accordingly, brains from embryonic DYRK1A transgenic mice exhibited elevated levels of Dyrk1A, Ser-15 (mouse Ser-18)-phosphorylated p53, and p21(CIP1) as well as impaired neuronal proliferation. These findings suggest that up-regulation of Dyrk1A contributes to altered neuronal proliferation in DS through specific phosphorylation of p53 at Ser-15 and subsequent p21(CIP1) induction
Observability analysis of power distribution systems with distributed energy resources using correlational measurements
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2019Cataloged from PDF version of thesis.Includes bibliographical references (pages 57-59).In this thesis, an observability analysis framework is proposed for power distribution systems. The framework analyzes the sufficiency of the available measurements for monitoring the system. In the areas of the network where sufficient sensors have been deployed, the complex voltage at the nodes may be estimated. The framework also provides a metric that quantifies the accuracy of these voltage estimates. Due to the cost of sensors and the size of distribution systems, it is frequently the case that the available measurements are insufficient for complete observability of the system. In this thesis, the author proposes the use of Correlational Measurements (CMs) for improving distribution system observability by leveraging correlation between loads and between Distributed Energy Resources (DERs). Load correlation due to class-residential, commercial, industrial, etc.- is captured via correlational load measurements, the first type of CM. Injection correlation of DERs-such as wind turbines located in proximity-is captured via correlational DER measurements, the second type of CM. This thesis presents the CM formulation and derives modified node voltage and branch current based state estimators (NVSE and BCSE) accommodating CMs. Additionally, this thesis contains an on-line parameter estimation scheme for CMs that improves the accuracy of state estimates over time. The observability analysis framework with CMs is demonstrated through simulations on the IEEE 123 Node Distribution Test Feeder. It is shown that the introduction of CMs leads to improved observability of the system with only a 0.7% decrease in state estimation accuracy for NVSE and a 0.5% increase in state estimation accuracy for BCSE.by Yohan M. John.S.M.S.M. Massachusetts Institute of Technology, Department of Mechanical Engineerin
My ministry with primary children Central Presbyterian Church Atlanta, Georgia September 1970 - April 1972, 1973
No full textTHE REVIEW OF KOREAN STUDIES Vol. 14 N. 1 (2011. 3)
No full textArticles 1. Joseon in Color / Kim Seok-hee, page(s): 7-34 2. Joseon Kings’ Personal Belief in Buddhism and its Political Significance / Pu Nam Chul, page(s): 35-55 3. Education and Family in Korean Society / Yang Young-Kyun, page(s): 57-87 4. Education for Young North Korean Migrants / Lee Soo-Jung, page(s): 89-112 Materials on Korean Studies 5. The Korean Wave and Lao People’s Perception of Korea / Lee Yohan , Vilayphone Somsamone, page(s): 115-143 Book Reviews 6. Unyŏng-Jŏn: A Love Affair a..
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