19 results on '"Ah-Young Song"'
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2. Enhanced Carbon Dioxide Capture from Diluted Streams with Functionalized Metal–Organic Frameworks
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Andrzej Gładysiak, Ah-Young Song, Rebecca Vismara, Madison Waite, Nawal M. Alghoraibi, Ammar H. Alahmed, Mourad Younes, Hongliang Huang, Jeffrey A. Reimer, and Kyriakos C. Stylianou
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Chemistry ,QD1-999 - Published
- 2024
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3. Water-Assisted Transformation of Aluminum Alloys to Ceramic Nanowires and Aerogels
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Fujia Wang, Zhijian Sun, Samik Jhulki, Wenbin Fu, Kostiantyn Turcheniuk, Billy Johnson, Doyoub Kim, Crystal Jain, Ah-Young Song, Yawei Zhang, Kaixi Chen, Aashray Narla, Wenqiang Hu, Dov Wallack, Chingping Wong, and Gleb Yushin
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General Chemical Engineering ,Biomedical Engineering ,General Materials Science - Published
- 2023
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4. Characterization of Chemisorbed Species and Active Adsorption Sites in Mg–Al Mixed Metal Oxides for High-Temperature CO2 Capture
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Alicia Lund, G. V. Manohara, Ah-Young Song, Kevin Maik Jablonka, Christopher P. Ireland, Li Anne Cheah, Berend Smit, Susana Garcia, and Jeffrey A. Reimer
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General Chemical Engineering ,Materials Chemistry ,General Chemistry - Published
- 2022
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5. Ginsenoside F1 Promotes Cytotoxic Activity of NK Cells via Insulin-Like Growth Factor-1-Dependent Mechanism
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Hyung-Joon Kwon, Heejae Lee, Go-Eun Choi, Soon Jae Kwon, Ah Young Song, So Jeong Kim, Woo Seon Choi, Sang-Hyun Hwang, Sun Chang Kim, and Hun Sik Kim
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natural killer cell ,ginsenoside ,cytotoxicity ,cancer surveillance ,IGF-1 ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Ginsenosides are the principal active components of ginseng and are considered attractive candidates for combination cancer therapy because they can kill tumors and have favorable safety profiles. However, the overall benefit of ginsenosides remains unclear, particularly in cancer immunosurveillance, considering the controversial results showing repression or promotion of immune responses. Here we identify a potentiating role of ginsenoside F1 (G-F1) in cancer surveillance by natural killer (NK) cells. Among 15 different ginsenosides, G-F1 most potently enhanced NK cell cytotoxicity in response to diverse activating receptors and cancer cells. G-F1 also improved cancer surveillance in mouse models of lymphoma clearance and metastatic melanoma that rely on NK cell activity. G-F1-treated NK cells exhibited elevated cytotoxic potential such as upregulation of cytotoxic mediators and of activation signals upon stimulation. NK cell potentiation by G-F1 was antagonized by insulin-like growth factor (IGF)-1 blockade and recapitulated by IGF-1 treatment, suggesting the involvement of IGF-1. Thus, our results suggest that G-F1 enhances NK cell function and may have chemotherapeutic potential in NK cell-based immunotherapy. We anticipate our results to be a starting point for further comprehensive studies of ginsenosides in the immune cells mediating cancer surveillance and the development of putative therapeutics.
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- 2018
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6. Scalable Pore Engineering Strategy for Promoting Ion Transport and Rate Capability in Thick Li-Ion Battery Electrodes
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Doyoub Kim, Gleb Yushin, Alexandre Magasinski, Yueyi Sun, Baolin Wang, Aashray Narla, Seung-Hun Lee, Hana Yoo, Samik Jhulki, Ah-Young Song, Jinho Hah, Ting Zhu, and Alexander Alexeev
- Abstract
Since the first commercialization of lithium-ion batteries (LIBs) in the early 1990s, previous research has been extensive on electrode material development. Due to its high volumetric energy and power densities and its low cost, the LIBs have aided in the widespread adoption of advanced mobile electronic devices, slowly spurred the market penetration of electric vehicles (EVs) globally and been incorporated in household energy storage systems to promote efficient use of renewable energy1,2. Unfortunately, after rapid improvements in LIB technology, the present progress in increasing energy density and reducing the costs of LIBs has been slow. To overcome the performance limitations on the material side, increasing the nickel (Ni) content of layered lithium nickel cobalt aluminum oxide (NCA) and lithium nickel cobalt manganese oxide (NCM) cathode materials and blending silicon with graphite anode materials have shown promise3,4,5. On the manufacturing side, there is a push to use thicker and denser electrodes and increase areal capacity loadings from 3-4 mAh/cm2 to 5-7 mAh/cm2 to reduce the mass and volume fraction of inactive materials and thus reduce costs and improve the energy density and specific energy of LIB cells beyond about 700 Wh/L and 250 Wh/kg, respectively6.-8 . Unfortunately, the characteristic Li+ ion diffusion time is proportional to the square of the average diffusion path through the electrode, which depends on both the electrode thickness and the tortuosity. As a result, the charging time and power performance characteristics in high-loading, dense electrodes may become undesirably poor. Herein, we report on several manufacturing pathways to create straight channel pores within electrodes to accelerate electrolyte wetting and facilitate rapid ion transport to overcome these rate limitations. References: Armand, M. & Tarascon, J.-M. Building Better Batteries. Nature 451, 652–657 (2008). Larcher, D. & Tarascon, J.-M. Towards greener and more sustainable batteries for Electrical Energy Storage. Nature Chemistry 7, 19–29 (2014). Manthiram, A., Knight, J. C., Myung, S.-T., Oh, S.-M. & Sun, Y.-K. Nickel-rich and lithium-rich layered oxide cathodes: Progress and perspectives. Advanced Energy Materials 6, 1501010 (2015). Liu, W. et al. Nickel-rich layered lithium transition-metal oxide for high-energy lithium-ion batteries. Angewandte Chemie International Edition 54, 4440–4457 (2015). Eshetu, G. G. et al. Production of high-energy Li-ion batteries comprising silicon-containing anodes and insertion-type cathodes. Nature Communications 12, (2021). Kuang, Y., Chen, C., Kirsch, D. & Hu, L. Thick electrode batteries: Principles, opportunities, and challenges. Advanced Energy Materials 9, 1901457 (2019). Patry, G., Romagny, A., Martinet, S. & Froelich, D. Cost modeling of lithium‐ion battery cells for Automotive Applications. Energy Science & Engineering 3, 71–82 (2014). Turcheniuk, K., Bondarev, D., Amatucci, G. G. & Yushin, G. Battery materials for low- cost electric transportation. Materials Today 42, 57–72 (2021).
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- 2022
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7. Transformation of bulk alloys to inorganic nanowires
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Danni Lei, Jim Benson, Ah-Young Song, Shunrui Luo, Gleb Yushin, Alexandre Magasinski, Fujia Wang, and Kostiantyn Turcheniuk
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- 2020
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8. Long cycle stability of conversion metal fluoride cathodes in polymer electrolytes
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Do-Youb Kim, Alexandre Magasinski, Yiran Xiao, Ah-Young Song, Gleb Yushin, Dmitry Bondarev, Xiaolei Ren, Qiao Huang, and Kostiantyn Turcheniuk
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- 2020
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9. Kokumi Taste Active Peptides Modulate Salt and Umami Taste
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Jie Qian, Shobha Mummalaneni, Vijay Lyall, Mee-Ra Rhyu, Ah-Young Song, Hee-Jin Son, Eun-Young Kim, Yi-Seul Kim, and John R. Grider
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0301 basic medicine ,Taste ,Salt (chemistry) ,lcsh:TX341-641 ,Stimulation ,Peptide ,Umami ,salty ,Pharmacology ,Article ,kokumi ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,amiloride-insensitive salt taste pathway ,Benzamil ,chorda tympani ,Animals ,Humans ,Channel blocker ,Sodium Chloride, Dietary ,chemistry.chemical_classification ,Nutrition and Dietetics ,Sodium ,Glutamate receptor ,Fishes ,Taste Perception ,Taste Buds ,umami ,Korean soy sauce ,Electrophysiological Phenomena ,Rats ,030104 developmental biology ,chemistry ,Models, Animal ,lcsh:Nutrition. Foods and food supply ,030217 neurology & neurosurgery ,Food Science - Abstract
Kokumi taste substances exemplified by g-glutamyl peptides and Maillard Peptides modulate salt and umami tastes. However, the underlying mechanism for their action has not been delineated. Here, we investigated the effects of a kokumi taste active and inactive peptide fraction (500-10,000 Da) isolated from mature (FIIm) and immature (FIIim) Ganjang, a typical Korean soy sauce, on salt and umami taste responses in humans and rodents. Only FIIm (0.1&ndash, 1.0%) produced a biphasic effect in rat chorda tympani (CT) taste nerve responses to lingual stimulation with 100 mM NaCl + 5 mM benzamil, a specific epithelial Na+ channel blocker. Both elevated temperature (42 °, C) and FIIm produced synergistic effects on the NaCl + benzamil CT response. At 0.5% FIIm produced the maximum increase in rat CT response to NaCl + benzamil, and enhanced salt taste intensity in human subjects. At 2.5% FIIm enhanced rat CT response to glutamate that was equivalent to the enhancement observed with 1 mM IMP. In human subjects, 0.3% FIIm produced enhancement of umami taste. These results suggest that FIIm modulates amiloride-insensitive salt taste and umami taste at different concentration ranges in rats and humans.
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- 2020
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10. Progressive Impairment of NK Cell Cytotoxic Degranulation Is Associated With TGF-β1 Deregulation and Disease Progression in Pancreatic Cancer
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Eunsung Jun, Ah Young Song, Ji-Wan Choi, Hyeon Ho Lee, Mi-Yeon Kim, Dae-Hyun Ko, Hyo Jeong Kang, Seong Who Kim, Yenan Bryceson, Song Cheol Kim, and Hun Sik Kim
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lcsh:Immunologic diseases. Allergy ,Cytotoxicity, Immunologic ,pancreatic cancer ,Immunology ,Peripheral blood mononuclear cell ,Cell Degranulation ,Flow cytometry ,Transforming Growth Factor beta1 ,TGF-β1 ,Pancreatic cancer ,Biomarkers, Tumor ,medicine ,Humans ,Immunology and Allergy ,Cytotoxic T cell ,Original Research ,natural killer cells ,medicine.diagnostic_test ,business.industry ,Degranulation ,Cancer ,medicine.disease ,NKG2D ,Killer Cells, Natural ,Pancreatic Neoplasms ,Immunosurveillance ,Disease Progression ,Cancer research ,cytotoxicity ,prognosis ,lcsh:RC581-607 ,business - Abstract
Natural killer (NK) cells are key effectors in cancer immunosurveillance and can be used as a prognostic biomarker in diverse cancers. Nonetheless, the role of NK cells in pancreatic cancer (PC) remains elusive, given conflicting data on their association with disease prognosis. In this study, using conventional K562 target cells and complementary engineered target cells providing defined and synergistic stimulation for NK cell activation, a correlation between impaired NK cell cytotoxic degranulation and PC progression was determined. Peripheral blood mononuclear cells (PBMCs) from 31 patients with newly diagnosed PC, 24 patients with non-malignant tumors, and 37 healthy controls were analyzed by flow cytometry. The frequency, phenotype, and effector functions of the NK cells were evaluated, and correlations between NK cell functions and disease stage and prognosis were analyzed. The results demonstrated that effector functions, but not frequency, of NK cells was progressively decreased on a per-cell basis during PC progression. Impaired cytotoxic degranulation, but not IFN-γ production, was associated with clinical features indicating disease progression, such as high serum CA19-9 and high-grade tumors. Significantly, this impairment correlated with cancer recurrence and mortality in a prospective analysis. Furthermore, the impaired cytotoxic degranulation was unrelated to NKG2D downregulation but was associated with increased circulating and tumor-associated TGF-β1 expression. Thus, NK cell cytotoxic activity was associated with PC progression and may be a favorable biomarker with predictive and prognostic value in PC.
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- 2019
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11. Critical Media Literacies in the Twenty-First Century: Writing Autoethnographies, Making Connections, and Creating Virtual Identities
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Ah-Young Song
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Multimedia ,Communication ,05 social sciences ,Media studies ,Twenty-First Century ,050301 education ,computer.software_genre ,Education ,Social integration ,Critical theory ,Ethnography ,Media literacy ,0501 psychology and cognitive sciences ,Sociology ,Computer-mediated communication ,0503 education ,computer ,Global education ,Cultural pluralism ,050104 developmental & child psychology - Published
- 2017
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12. Comparison of effectiveness of edible coatings using emulsions containing lemongrass oil of different size droplets on grape berry safety and preservation
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Yoon Ah Oh, Ah Young Song, Yeong Ji Oh, Kyung Bin Song, Jin Sung Won, and Sea C. Min
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0301 basic medicine ,030109 nutrition & dietetics ,Chromatography ,Antioxidant ,medicine.medical_treatment ,04 agricultural and veterinary sciences ,engineering.material ,040401 food science ,law.invention ,Chitosan ,Pascalization ,03 medical and health sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,chemistry ,Coating ,law ,Emulsion ,engineering ,medicine ,Particle ,Food science ,Essential oil ,Food Science ,Mesophile - Abstract
Effects of lemongrass oil (LO) droplet size in the LO/chitosan emulsion on the emulsion's coating effectiveness in improving microbiological safety and preserving grape berries ( Vitis vinifera L. × V. labruscana Bailey) were investigated. LO was homogenized with a chitosan solution (1 g/100 g) and Tween 20 (0.25 g/100 g) by high shear mixing (HSM; 10,000 rpm, 1 min) or dynamic high pressure processing (DHP; 103–172 MPa, 1–3 passes), forming LO coating emulsions. The particle sizes of the HSM and DHP emulsions were 461.9–632.6 nm and 204.2–378.8 nm, respectively. DHP emulsions were more stable than HSM emulsions. Compared with the HSM emulsion, the DHP emulsion coating resulted in higher initial inhibition of Salmonella typhimurium ; greater growth inhibition of total mesophilic aerobes, yeasts, and molds; and retention of color, total soluble solid content, and antioxidant activity during storage at 25 °C ( P Salmonella and preserving grape berries, compared with the coating with larger droplets.
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- 2017
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13. Synthesis and Magnetic Properties of Multifunctional Fe$_{3}$O$_{4}$-AuPt Core-Shell Nanoparticles
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Ji Sung Lee, Jun Hua Wu, Ah-Young Song, Reasmey P. Tan, Ji Hyun Min, and Young Keun Kim
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Materials science ,Nanostructure ,Chemical engineering ,Ferromagnetism ,Surface plasmon ,X-ray crystallography ,Nanoparticle ,Nanotechnology ,Particle size ,Electrical and Electronic Engineering ,Surface plasmon resonance ,Electronic, Optical and Magnetic Materials ,Superparamagnetism - Abstract
This paper describes the synthesis and magnetic properties of multifunctional Fe3O4-AuPt core-shell nanoparticles. The Fe3O4-AuPt core-shell nanoparticles were synthesized by a one-pot polyol process in two consecutive steps from Fe, Au, and Pt precursors. The structural characterization and property analysis proves the formation of the core-shell nanostructure fusing the multifunctionality in a single entity. The TEM observation shows that the Fe3O4-AuPt core-shell nanoparticles are highly crystalline and uniform in size distribution, with an averaged particle size of ~12.5 nm in diameter, whereas the X-ray diffraction patterns provide further substantiation. The surface plasmon resonance arising from the AuPt nano-shell was revealed by UV-vis spectroscopy, while the magnetic measurements by VSM and PPMS demonstrate the well-defined superparamagnetic and/or soft-ferromagnetic behavior of the Fe3O4-AuPt core-shell nanoparticles.
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- 2009
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14. Ion Conductivities: Protons Enhance Conductivities in Lithium Halide Hydroxide/Lithium Oxyhalide Solid Electrolytes by Forming Rotating Hydroxy Groups (Adv. Energy Mater. 3/2018)
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Gleb Yushin, Marco Olguin, Anirudh Ramanujapuram, Punith Upadhya, Alexandre Magasinski, Yiran Xiao, Kostiantyn Turcheniuk, Ah-Young Song, Jim Benson, Lamartine Meda, and Oleg Borodin
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Materials science ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Halide ,chemistry.chemical_element ,02 engineering and technology ,Solid state electrolyte ,021001 nanoscience & nanotechnology ,Ion ,Antiperovskite ,chemistry.chemical_compound ,chemistry ,X-ray crystallography ,Fast ion conductor ,Hydroxide ,General Materials Science ,Lithium ,0210 nano-technology - Published
- 2018
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15. Influence of Protons on the Lithium Transport Mechanism in Antiperovskite Solid Electrolytes from Molecular Dynamics Simulations
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Oleg Borodin, Marco Olguin, Ah-Young Song, Yiran Xiao, Kostiantyn Turcheniuk, Anirudh Ramanujapuram, Jim Benson, Alexandre Magasinski, Lamartine Meda, and Gleb Yushin
- Abstract
Battery energy storage has become a critical component of civil and military operations because of the rapidly growing demands in consumer electronics, electric vehicles and the power-consuming systems carried by soldiers on the battlefield. Currently utilized batteries are flammable and suffer from an insufficient high specific energy, which poses major safety issues creating a tactical burden for the soldiers. The use of solid state batteries may offer enhanced safety and increased energy density. Previous modeling studies of the superionic lithium-rich anti-perovskites conductors focused on Li3OX (X = Cl, Br) structures and reported a variety of the charge transport mechanisms ranging from the low-barrier three-atom hop mechanism involving vacancies, Li hops to the nearest neighbor, Li interstitial dumbbells, and diffusion of the Li+ interstitials in LiCl-deficient Li3OCl that outnumber vacancies by 2–3 orders of magnitude as predicted by the shell model. It is, however, quite challenging to completely remove protons from these anti-perovskite conductors during synthesis, highlighting the importance of understanding the influence of protons on conductivity and electrochemical properties for these superionic lithium-rich anti-perovskite conductors.(1, 2) Born-Oppenheimer molecular dynamics (BOMD) simulations of Li2+xOH1-xCl (0≤x≤1) solid electrolytes were performed in order to gain insights into the mechanism of lithium transport and the influence of H concentration, complementing previous modeling studies of H-free antiperovskites. The simulation cell was comprised of 320 atoms. Density Functional Theory (DFT) calculations were performed with the QUICKSTEP module of the CP2K code, which implements the dual Gaussian and Plane Waves (GPW) method. The gamma point supercell approach was used in combination with 3-dimensioanl Periodic Boundary Conditions (PBC). Calculations were performed using the spin-polarized Perdew-Burke-Ernzerhof (PBE) exchange correlation functional with Grimme’s D3 dispersion correction. BOMD simulations predicted a significant enhancement of the lithium diffusion with the increased fraction of protons in agreement with experimental data. The lithium transport mechanism was found to be closely coupled with the rotation of a relatively short OH-group within the protonated electrolytes. Moreover, lithium jump events were found to be highly-correlated. Figure 1a shows a snapshot of the simulation box. In order to gain further insight into the transport mechanics, the motion of the fastest lithium cations in Li2.5OH0.5Cl solid electrolyte are highlighted with different colors. Overlap between trajectories of the fastest lithium cations shown by red arrows is indicative of the highly-correlated fashion of the lithium jumps.(2) We will also discuss changes of band gaps and band alignments that were calculated using DFT hybrid functionals as markers for electrochemical stability. We anticipate that our findings will reduce the existing confusions and show new avenues for tuning solid electrolyte compositions for further improved Li-ion conductivities. Different aspects of this work were supported by NASA Minority University Research and Education Project (MUREP; NASA grant NNX15AP44A and interagency agreement NND16AA29I with ARL for modeling) and ARPA-E (grant DE-AR0000779). References 1. Y. Li, W. Zhou, S. Xin, S. Li, J. Zhu, X. Lü, Z. Cui, Q. Jia, J. Zhou, Y. Zhao and J. B. Goodenough, Angew. Chem. Int. Ed., 55, 9965 (2016). 2. A.-Y. Song, Y. Xiao, K. Turcheniuk, A. Ramanujapuram, J. Benson, A. Magasinski, M. Oguin, L. Meda, O. Borodin and G. Yushin, (submitted)(2017). Figure 1. A snapshot from MD simulations of Li2.5(OH)0.5Cl (a). Trajectories of the fastest Li+ cations during 10 ps BOMD run of Li2.5OH0.5Cl SSE using different colors to denote distinct Li+ (b). Red arrows show overlap between the Li+ trajectories that is indicative of the Li+ correlated motion for the fastest moving Li+. Figure 1
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- 2017
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16. A kinematic analysis of relative stability of the lower extremities between subjects with and without chronic low back pain
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Dongchul C. Lee, Yoon Hyuk Kim, Hang Jin Jo, Ah Young Song, Paul S. Sung, and Kyung Lee
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Kinematics ,Weight-Bearing ,Disability Evaluation ,Young Adult ,Physical medicine and rehabilitation ,medicine ,Group interaction ,Humans ,Orthopedics and Sports Medicine ,Young adult ,Postural Balance ,Gait Disorders, Neurologic ,Leg ,Rehabilitation ,business.industry ,Confounding ,Middle Aged ,Low back pain ,Relative stability ,Chronic low back pain ,Biomechanical Phenomena ,Physical therapy ,Surgery ,Female ,Original Article ,medicine.symptom ,Chronic Pain ,business ,Low Back Pain - Abstract
Even though a number of studies have evaluated postural adjustments based on kinematic changes in subjects with low back pain (LBP), kinematic stability has not been examined for abnormal postural responses during the one leg standing test. The purpose of this study was to evaluate the relative kinematic stability of the lower extremities and standing duration in subjects with and without chronic LBP. In total, 54 subjects enrolled in the study, including 28 subjects without LBP and 26 subjects with LBP. The average age of the subjects was 37.8 ± 12.6 years and ranged from 19 to 63 years. The outcome measures included normalized holding duration and relative kinematic stability. All participants were asked to maintain the test position without visual input (standing on one leg with his/her eyes closed and with the contra lateral hip flexed 90°) for 25 s. The age variable was used as a covariate to control confounding effects for the data analyses. The control group demonstrated significantly longer holding duration times (T = −2.78, p = 0.007) than the LBP group (24.6 ± 4.2 s vs. 20.5 ± 6.7 s). For the relative kinematic stability, there was a difference in dominance side (F = 9.91, p = 0.003). There was a group interaction between side and lower extremities (F = 11.79, p = 0.001) as well as an interaction between age and dominance side (F = 7.91, p = 0.007). The relative kinematic stability had a moderate negative relationship with age (r = −0.60, p = 0.007) in subjects without LBP. Clinicians need to understand the effects of age and relative stability, which decreased significantly in the single leg holding test, in subjects with LBP in order to develop effective rehabilitation strategies.
- Published
- 2010
17. The Critical Peer Review as a Transactional Process: Peer Editing Personal Narratives in the Secondary English Classroom.
- Author
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Ah-Young Song
- Subjects
EYEWITNESS accounts ,SCHOLARLY peer review ,PROOFREADING ,EDITING ,ENGLISH literature education in secondary schools - Abstract
At the center of this essay is what happens when Louise Rosenblatt's transactional model of reading is applied to writing workshops and peer evaluations of personal essays in the English classroom. Following the tradition of the Critical Friends Group (CFG) model, I call the readings of peer essays critical peer reviews because students act as contributors who offer encouraging support and candid criticisms as they critically examine peers' artifacts. Critical peer reviews are built on a community of participants engaged in structured reflection, effective feedback, and constructive revisions; additionally, they rotate and serve as writer/reader, observer/participant, and artist/critic. [ABSTRACT FROM AUTHOR]
- Published
- 2017
18. A kinematic analysis of relative stability of the lower extremities between subjects with and without chronic low back pain.
- Author
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Hang Jin Jo, Ah Young Song, Kyung Jun Lee, Lee, Dongchul C., Yoon Hyuk Kim, and Sung, Paul S.
- Subjects
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KINEMATICS , *LEG physiology , *BACKACHE , *POSTURE , *PHYSIOLOGY , *ONE-leg resting position , *PATIENTS - Abstract
Even though a number of studies have evaluated postural adjustments based on kinematic changes in subjects with low back pain (LBP), kinematic stability has not been examined for abnormal postural responses during the one leg standing test. The purpose of this study was to evaluate the relative kinematic stability of the lower extremities and standing duration in subjects with and without chronic LBP. In total, 54 subjects enrolled in the study, including 28 subjects without LBP and 26 subjects with LBP. The average age of the subjects was 37.8 ± 12.6 years and ranged from 19 to 63 years. The outcome measures included normalized holding duration and relative kinematic stability. All participants were asked to maintain the test position without visual input (standing on one leg with his/her eyes closed and with the contra lateral hip flexed 90°) for 25 s. The age variable was used as a covariate to control confounding effects for the data analyses. The control group demonstrated significantly longer holding duration times ( T = −2.78, p = 0.007) than the LBP group (24.6 ± 4.2 s vs. 20.5 ± 6.7 s). For the relative kinematic stability, there was a difference in dominance side ( F = 9.91, p = 0.003). There was a group interaction between side and lower extremities ( F = 11.79, p = 0.001) as well as an interaction between age and dominance side ( F = 7.91, p = 0.007). The relative kinematic stability had a moderate negative relationship with age ( r = −0.60, p = 0.007) in subjects without LBP. Clinicians need to understand the effects of age and relative stability, which decreased significantly in the single leg holding test, in subjects with LBP in order to develop effective rehabilitation strategies. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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19. Synthesis and Magnetic Properties of Multifunctional Fe3O4-AuPt Core-Shell Nanoparticles.
- Author
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Ah-Young Song, Jun Hua Wu, Ji Hyun Mi, Tan, Reasmey P., Ji Sung Lee, and Young Keun Kim
- Subjects
- *
MAGNETIC properties , *NANOPARTICLES , *NANOSTRUCTURES , *FERROMAGNETISM , *IRON oxides , *SURFACE plasmon resonance - Abstract
This paper describes the synthesis and magnetic properties of multifunctional Fe3O4-AuPt core-shell nanoparticles. The Fe3O4-Au Pt core-shell nanoparticles were synthesized by a one-pot polyol process in two consecutive steps from Fe, Au, and Pt precursors. The structural characterization and property analysis proves the formation of the core-shell nanostructure fusing the multifunctionality in a single entity. The TEM observation shows that the Fe3O4-AuPt core-shell nanoparticles are highly crystalline and uniform in size distribution, with an averaged particle size of ~12.5 nm in diameter, whereas the X-ray diffraction patterns provide further substantiation. The surface plasmon resonance arising from the AuPt nano-shell was revealed by UV-vis spectroscopy, while the magnetic measurements by YSM and PPMS demonstrate the well-defined superparamagnetic and/or soft-ferromagnetic behavior of the Fe3O4-AuPt core-shell nanoparticles. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
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