221 research outputs found
Created era estimation of old Korean documents via deep neural network
Full text linkIn general, the created era of a literary work is significant information for understanding the background and the literary interpretation of the work. However, in the case of literary works of old Korea, especially works created in Hangul, there are few works of which the era of creation are known. In this paper, the created era of old Korean documents was estimated based on artificial intelligence. Hangul, a Korean letter system where one syllable is one character, has more than 10,000 combinations of characters, so it is available to predict changes in the structure or grammar of Hangul by analyzing the frequency of characters. Accordingly, a deep neural network model was constructed based on the term frequency of each character in Hangul. Model training was performed based on 496 documents with known publication years, and the mean-absolute-error of the test set for the entire prediction range from 1447 to 1934 was 13.77 years for test sets and 15.8 years for validation sets, which is less than an error ratio of 3.25% compared to the total year range. In addition, the predicted results of works from which only the approximate creation time was inferred were also within the range, and the predicted creation years for other divisions of the identical novel were similar. These results show that the deep neural network model based on character term frequency predicted the creation era of old Korean documents properly. This study is expected to support the literary history of Korea within the period from 15C to 19C by predicting the period of creation or enjoyment of the work. In addition, the method and algorithm using syllable term frequency are believed to have the potential to apply in other language documents.N
Developmental trajectories of behavior problems of youth involved in child welfare: influence of caregiver and peer relationships
No full textThis dissertation examined the developmental trajectories of adolescent youth involved with the child welfare system, particularly focusing on their externalizing and internalizing behavioral problems. The study investigated how adolescents’ relationships with caregivers and peers change over time and how they affect these behavioral outcomes. The study also explored whether removing youth from their biological family predicted distinct trajectories of behavior functioning compared to those who remained at home. Data are from the National Survey of Child and Adolescent Well-being (NSCAW), a national probability sample of children and adolescents who have contact with child protective services. Two types of structural equation modeling (SEM), latent growth curve modeling and cross-lagged designs were conducted using M-Plus. All analyses were conducted with sample weights.
Youths reported significantly decreasing internalizing behavior problems over the study period of 36 months. On the other hand, externalizing problems remained considerably stable over time. In order to investigate if youth had different development trajectories depending on whether they stayed at home or were placed in out-of-home care, the sample was divided into four placement groups, i.e., out-of-home youth, in-home youth, the initial out-of-home youth (those who returned home later), and the initial in-home youth (those who were removed from home later). When group differences were investigated, youths did not show significant differences in the initial levels and rates of change of internalizing or externalizing problems over time. In addition, relationships with caregivers and peers were found to be comparable across four groups. Caregiver and peer relationships were significantly related to youths’ internalizing and externalizing problems at baseline as well as over time. When temporal causal relations among caregiver relationships, peer relationships, and behavior problems were investigated, externalizing problems of youth at 18 months were found to affect their caregiver and peer relationships at 36 months.Ph.D.Includes bibliographical references (p. 100-113)by Inseon Le
Figure_S2 – Supplemental material for Ectopic transient overexpression of <i>OCT-4</i> facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells
No full textSupplemental material, Figure_S2 for Ectopic transient overexpression of OCT-4 facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells by Seung Hyun L Kim, Seunghun S Lee, Inseon Kim, Janet Kwon, Song Kwon, Taegeun Bae, Junho Hur, Hwajin Lee and Nathaniel S Hwang in Journal of Tissue Engineering</p
suppl_tables – Supplemental material for Ectopic transient overexpression of <i>OCT-4</i> facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells
No full textSupplemental material, suppl_tables for Ectopic transient overexpression of OCT-4 facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells by Seung Hyun L Kim, Seunghun S Lee, Inseon Kim, Janet Kwon, Song Kwon, Taegeun Bae, Junho Hur, Hwajin Lee and Nathaniel S Hwang in Journal of Tissue Engineering</p
Figure_S1 – Supplemental material for Ectopic transient overexpression of <i>OCT-4</i> facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells
No full textSupplemental material, Figure_S1 for Ectopic transient overexpression of OCT-4 facilitates BMP4-induced osteogenic transdifferentiation of human umbilical vein endothelial cells by Seung Hyun L Kim, Seunghun S Lee, Inseon Kim, Janet Kwon, Song Kwon, Taegeun Bae, Junho Hur, Hwajin Lee and Nathaniel S Hwang in Journal of Tissue Engineering</p
Ablation of Ca2+ channel beta 3 subunit leads to enhanced N-methyl-D-aspartate receptor-dependent long term potentiation and improved long term memory
No full textThe beta subunits of voltage-dependent Ca2+ channels (VDCCs) have marked effects on the properties of the pore-forming alpha(1) subunits of VDCCs, including surface expression of channel complexes and modification of voltage-dependent kinetics. Among the four different beta subunits, the beta 3 subunit (Ca-v beta 3) is abundantly expressed in the hippocampus. However, the role of Ca-v beta 3 in hippocampal physiology and function in vivo has never been examined. Here, we investigated Ca-v beta 3-deficient mice for hippocampus-dependent learning and memory and synaptic plasticity at hippocampal CA3-CA1 synapses. Interestingly, the mutant mice exhibited enhanced performance in several hippocampus-dependent learning and memory tasks. However, electrophysiological studies revealed no alteration in the Ca2+ current density, the frequency and amplitude of miniature excitatory postsynaptic currents, and the basal synaptic transmission in the mutant hippocampus. On the other hand, however, N-methyl-D-aspartate receptor (NMDAR)-mediated synaptic currents and NMDAR-dependent long term potentiation were significantly increased in the mutant. Protein blot analysis showed a slight increase in the level of NMDAR-2B in the mutant hippocampus. Our results suggest a possibility that, unrelated to VDCCs regulation, Ca-v beta 3 negatively regulates the NMDAR activity in the hippocampus and thus activity-dependent synaptic plasticity and cognitive behaviors in the mouse.This work was supported by the National Honor Scientist Program of Korea, grants from Korea Institute of Science and Technology, the National Creative Research Initiatives of the Ministry of Science and Technology of Korea, and Virginia Commonwealth University Medical Center Grant NEI EY12716. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact
Role of the alpha 1G T-type calcium channel in spontaneous absence seizures in mutant mice
No full textAlterations in thalamic T-type Ca2+ channels are thought to contribute to the pathogenesis of absence seizures. Here, we found that mice with a null mutation for the pore-forming alpha1A subunits of P/Q-type channels (alpha1A(-/-) mice) were prone to absence seizures characterized by typical spike-and-wave discharges (SWDs) and behavioral arrests. Isolated thalamocortical relay (TC) neurons from these mice showed increased T-type Ca2+ currents in vitro. To examine the role of increased T-currents in alpha1A(-/-) TC neurons, we cross-bred alpha1A(-/-) mice with mice harboring a null mutation for the gene encoding alpha1G, a major isotype of T-type Ca2+ channels in TC neurons. alpha1A(-/-)/alpha1G(-/-) mice showed a complete loss of T-type Ca2+ currents in TC neurons and displayed no SWDs. Interestingly, alpha1A(-/-)/alpha1G(+/-) mice had 75% of the T-type Ca2+ currents in TC neurons observed in alpha1A (+/+)/alpha1G (+/+) mice and showed SWD activity that was quantitatively similar to that in alpha1A (-/-)/alpha1G (+/+) mice. Similar results were obtained using double-mutant mice harboring the alpha1G mutation plus another mutation also used as a model for absence seizures, i.e., lethargic (beta4(1h/1h)), tottering (alpha1A(tg/tg)), or stargazer (gamma2(stg/stg)). The present results reveal that alpha1G T-type Ca2+ channels play a critical role in the genesis of spontaneous absence seizures resulting from hypofunctioning P/Q-type channels, but that the augmentation of thalamic T-type Ca2+ currents is not an essential step in the genesis of absence seizures
A biofunctionalized viral delivery patch for spatially defined transfection
No full textGene therapy holds the significance of correcting genetic defects. However, difficulties in the in vivo delivery to the targeted tissues and systemic delivery remain the biggest challenges to be overcome. Here, a robust system of biofunctionalized polymeric layermediated lentiviral delivery was designed for the site-specific spatial and temporal control of viral gene delivery. Poly glycidyl methacrylate (pGMA) modification of a substrate via initiated chemical vapor deposition (iCVD) followed by polyethyleneimine (PEI) immobilization provided the adhesion site for the lentivirus. Furthermore, the polymeric patch based gene delivery system showed a high rate of gene transduction compared to bolus treatment. Furthermore, by using mask patterning, we were able to spatially pattern the lentivirus which allowed spatially defined transfection.
Enhanced stability and reusability of marine epoxide hydrolase using ship-in-a-bottle approach with magnetically-separable mesoporous silica
No full textWe developed magnetically-separable and highly-stable biocatalyst system of Mugil cephalus epoxide hydrolase (McEH) for enantioselective hydrolysis of racemic epoxides. McEH protein was adsorbed and cross-linked into mesoporous silica with bottle-neck mesopores, which effectively prevented the leaching of cross-linked McEH in a larger mesocellular pores. This ship-in-a-bottle approach allows for highly loaded and stable McEH system. For example, free McEH showed only 7.5% of initial activity under shaking condition at 80 h while ship-in-a-bottled McEH retained 79.5% of initial activity in the same condition. Stable McEH in magnetically-separable mesoporous silica could achieve the yield of 45% for the preparation of enantiopure (S)-styrene oxide with 98%ee. The magnetic nanoparticles pre-incorporated in mesoporous silica enabled an easy recovery of immobilized McEH for repetitive batch resolutions of racemic styrene oxide, allowing for more than 50% of the initial activity was retained after seven recycled uses. (C) 2012 Elsevier B.V. All rights reserved.
Crosslinked chitosan coating on magnetic mesoporous silica with pre-adsorbed carbonic anhydrase for carbon dioxide conversion
No full textCarbonic anhydrase (CA), an enzyme converting CO2 to bicarbonate, was adsorbed into magnetically-separable spherical mesocellular siliceous foam (Mag-S-MCF). Then, chitosan was adsorbed onto the surface of Mag-S-MCF with pre-adsorbed enzymes, and further crosslinked via the glutaraldehyde treatment. The resulting composite materials, the crosslinked chitosan coating on Mag-S-MCF with pre-adsorbed CA (ADS-CA/CS-GA), could effectively prevent leaching of enzymes, showing no decrease of enzyme activity under shaking (200 rpm) for 85 days. ADS-CA/CS-GA also showed no activity decrease under recycled uses via facile magnetic separation, and could be successfully used for the biocatalytic CO2 conversion to bicarbonate, which was further utilized to generate calcium carbonate in the second batch reactor. (C) 2015 Elsevier B.V. All rights reserved.
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