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Dissociation Constant of the Primary Amines and Quaternary Ammonium-methylorange Salts.

  • Kim, Bak-Kwang
    • YAKHAK HOEJI
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    • v.18 no.3
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    • pp.197-202
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    • 1974
  • The data pf dosspcoatopm cpmstamts for aliphatic amines and quaternary ammonium-methylorange salts are based on the electrosatic theory of conductance. Dissociation constants for primary amines nad quaternary ammonium-methylorange salts (1$\times$10$^{-5}$~1$\times$10$^{-3}$ M) in nitrobenzene solution or water solution was evaluated from the relation of the concentration and the electric conduction and the electric conductance at $25^{\circ}C$ Plots of ${\delta}C$ against reciprocal conductance were linear ; hence the center-to-center distance of this salt was 1.75 $\AA$ in nitrobenzene solution.

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Intrapulmonary Teratoma: Two Cases Report (폐 기형종 치험 2례)

  • Lee, Young;Huh, Chin-Chul;Lee, Kwon-Woo;Kwon, Ki-Jung;Lee, Ho-Il;Yoo, Hoe-Sung
    • Journal of Chest Surgery
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    • v.5 no.2
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    • pp.141-146
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    • 1972
  • The intrapulmonary teratoma is an extremely rare tumor. Since the orlginaI description by Black in 1981. about 19 cases have been reported in the would literature. We wish to describe the two cases of another patients with this extremely rare tumor.

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Disseminated adenovirus infection in a 10-year-old renal allograft recipient

  • Lee, Bora;Park, Eujin;Ha, Jongwon;Ha, Il Soo;Cheong, Hae Il;Kang, Hee Gyung
    • Kidney Research and Clinical Practice
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    • v.37 no.4
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    • pp.414-417
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    • 2018
  • Disseminated adenovirus infection can result in high mortality and morbidity in immunocompromised patients. Here, we report the case of a 10-year-old renal allograft recipient who presented with hematuria and dysuria. Adenovirus was isolated from his urine. His urinary symptoms decreased after intravenous hydration and reduction of immunosuppressants. However, 2 weeks later he presented with general weakness and laboratory tests indicated renal failure necessitating emergency hemodialysis. Adenovirus was detected in his sputum; therefore, intravenous ganciclovir and immunoglobulin therapy were initiated. Renal biopsy revealed diffuse necrotizing granulomatous tubulointerstitial nephritis compatible with renal involvement of the viral infection. Adenovirus was detected in his serum. Despite cidofovir administration for 2 weeks, adenovirus was also detected in the cerebrospinal fluid, resulting in generalized tonic-clonic seizure. The patient died 7 weeks after the onset of urinary symptoms. Adenovirus should be considered in screening tests for post-renal transplantation patients who present with hemorrhagic cystitis.

Taguchi method-optimized roll nanoimprinted polarizer integration in high-brightness display

  • Lee, Dae-Young;Nam, Jung-Gun;Han, Kang-Soo;Yeo, Yun-Jong;Lee, Useung;Cho, Sang-Hwan;Ok, Jong G.
    • Advances in nano research
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    • v.13 no.2
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    • pp.199-206
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    • 2022
  • We present the high-brightness large-area 10.1" in-cell polarizer display panel integrated with a wire grid polarizer (WGP) and metal reflector, from the initial design to final system development in a commercially feasible level. We have modeled and developed the WGP architecture integrated with the metal reflector in a single in-cell layer, to achieve excellent polarization efficiency as well as brightness enhancement through the light recycling effect. After the optimization of key experimental parameters via Taguchi method, the roll nanoimprint lithography employing a flexible large-area tiled mold has been utilized to create the 90 nm-pitch polymer resist pattern with the 54.1 nm linewidth and 5.1 nm residual layer thickness. The 90 nm-pitch Al gratings with the 51.4 nm linewidth and 2150 Å height have been successfully fabricated after subsequent etch process, providing the in-cell WGPs with high optical performance in the entire visible light regime. Finally we have integrated the WGP in a commercial 10.1" display device and demonstrated its actual operation, exhibiting 1.24 times enhancement of brightness compared to a conventional film polarizer-based one, with the contrast ratio of 1,004:1. Polarization efficiency and transmittance of the developed WGPs in an in-cell polarizer panel achieve 99.995 % and 42.3 %, respectively.

Osteoporosis and Osteoporotic Fractures in Gastrointestinal Disease

  • Oh, Hyun Jin;Ryu, Kum Hei;Park, Bum Joon;Yoon, Byung-Ho
    • Journal of Bone Metabolism
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    • v.25 no.4
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    • pp.213-217
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    • 2018
  • Patients with gastrointestinal disease (GI) are at risk for osteopenia or osteoporosis, which can lead to fractures. Although these patients may be at risk from a young age, gastroenterologists often overlook this fact in practice. There are well-known GI diseases associated with osteopenia and osteoporosis, such as the post-gastrectomy state, inflammatory bowel disease (IBD), and celiac disease. As there is an increase in the prevalence of IBD patients, newly diagnosed celiac disease in adulthood, and gastric cancer survivors following gastrectomy, bone disease in these patients becomes an important issue. Here, we have discussed osteoporosis and fractures in GI disease, especially in the postgastrectomy state, IBD, and celiac disease. Although the pathogenesis of bone loss in each disease has not been fully identified, we have confirmed that the prevalence of osteoporosis and fractures in each of these diseases is high. There are scarce studies comparing the prevalence of osteoporosis or osteoporotic fractures in GI disease patients with studies in postmenopausal women, and specific guidelines for their management in each disease have not been established. Intensive surveillance and management are needed to ensure that these patients attain peak bone mass for age and sex to prevent fractures.

Fed-batch Fermentations of Recombinant Escherichia coli to Produce Bacillus macerans CGTase

  • Park, Yong-Cheol;Kim, Chang-Sup;Kim, Chung-Im;Choi, Kyu-Hwan;Seo, Jin-Ho
    • Journal of Microbiology and Biotechnology
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    • v.7 no.5
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    • pp.323-328
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    • 1997
  • The recombinant Escherichia coli BL21(DE3)pLysE : pTCGT1 was grown to overproduce Bacillus macerans cyclodextrin glucanotransferase (CGTase) able to synthesize ${\alpha}$-cyclodextrin (CD) with a selectivity of 67%. A number of batch fermentations were performed to test the possibility of using lactose as an inducer of the E. coli T7 promoter system. A mixture of isopropyl ${\beta}$-D-thiogalactoside (IPTG) and lactose (1 : 1) gave a maximum CGTase activity of 2.4 U/ml, which was higher than the value obtained with induction by IPTG alone. Fed-batch fermentations involving a glucose-controlled growth period followed by a gene-expression phase with mixtures of IPTG and lactose were employed to achieve high cell density and thereby increase total CGTase activity. Optimized fed-batch fermentation using the modified inducer (IPTG : lactose=1 : 3) and 100 g/l yeast extract solution in the gene-expression phase resulted in a maximum CGTase activity of 62.9 U/ml and a final cell mass of 53.5 g/l, corresponding to a 31-fold increase in CGTase activity and a 29-fold increase in cell mass compared with the control batch fermentation.

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Water Repellency on a Nanostructured Superhydrophobic Carbon Fibers Network

  • Ko, Tae-Jun;Her, Eun-Kyu;Shin, Bong-Su;Kim, Ho-Young;Lee, Kwang-Ryeol;Hong, Bo-Ki;Kim, Sae-Hoon;Oh, Kyu-Hwan;Moon, Myoung-Woon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.224-224
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    • 2012
  • For decades, carbon fiber has expanded their application fields from reinforced composites to energy storage and transfer technologies such as electrodes for super-capacitors and lithium ion batteries and gas diffusion layers for proton exchange membrane fuel cell. Especially in fuel cell, water repellency of gas diffusion layer has become very important property for preventing flooding which is induced by condensed water could damage the fuel cell performance. In this work, we fabricated superhydrophobic network of carbon fiber with high aspect ratio hair-like nanostructure by preferential oxygen plasma etching. Superhydrophobic carbon fiber surfaces were achieved by hydrophobic material coating with a siloxane-based hydrocarbon film, which increased the water contact angle from $147^{\circ}$ to $163^{\circ}$ and decreased the contact angle hysteresis from $71^{\circ}$ to below $5^{\circ}$, sufficient to cause droplet roll-off from the surface in millimeter scale water droplet deposition test. Also, we have explored that the condensation behavior (nucleation and growth) of water droplet on the superhydrophobic carbon fiber were significantly retarded due to the high-aspect-ratio nanostructures under super-saturated vapor conditions. It is implied that superhydrophobic carbon fiber can provide a passage for vapor or gas flow in wet environments such as a gas diffusion layer requiring the effective water removal in the operation of proton exchange membrane fuel cell. Moreover, such nanostructuring of carbon-based materials can be extended to carbon fiber, carbon black or carbon films for applications as a cathode in lithium batteries or carbon fiber composites.

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Differential diagnosis of Trichostrongylus and hookworm eggs via PCR using ITS-1 sequence

  • Yong, Tai-Soon;Lee, Jong-Ho;Sim Seo-Bo;Lee, Jong-Weon;Min Duk-Young;Chai, Jong-Yil;S. Eom, Kee-Seon;Sohn Woon-Mok;Lee, Soon-Hyung;Rim, Han-Jong
    • Parasites, Hosts and Diseases
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    • v.45 no.1 s.141
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    • pp.69-74
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    • 2007
  • Trichostrongylus eggs observed in cellophane-thick smears are difficult, in practice, to distinguish from hookworm eggs. In order to overcome these limitations, a molecular approach was conducted. A Trichostrongylus colubriformis adult worm was obtained from a human in Laos, which was identified morphologically. ITS-1 sequence of this worm was determined, and found to be most similar with that of T. colubriformis among the Trichostrongylus spp. reported so far. Then, this sequence was compared with those of human hookworm species, Ancylostoma duodenale and Necator americanus, and species-specific oligonucleotide primers were designed. Polymerase chain reaction(PCR) using these primers evidenced specifically amplified PCR products of Trichostrongylus sp., A. duodenale and N. americanus from the eggs of each(520 bp, 690 bp, and 870 bp, respectively). A species-specific PCR technique can be developed in order to study the epidemiology of Trichostrongylus spp. and hookworms in endemic areas.

Analysis of Research Trends about Rural Landscape Published in Korean Academic Journals (국내학술지에 게재된 농촌경관 관련 연구동향 분석)

  • An, Duk-cho;Oh, hyung-eun;Park, Ji-hoon;Kang, Eun-ji;Kim, Yong-geun
    • Journal of Korean Society of Rural Planning
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    • v.21 no.3
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    • pp.121-129
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    • 2015
  • This article centers on 'rural landscape' in terms of subjects and subject-words among journals that are registered or would be registered in Korea Education and Research Information Service from 1995 up to 2014 to group 109 theses by subject that include planning, projects, residents' participation, that are fit for the purpose of this study so that research trends by journal, change in subjects by year and change in detailed subjects may be analyzed. Its detailed outcome is as follows. First, current situations of carrying theses by academic society shows that a total of 23 societies have conducted research, among which, International Society for Rural Plan In Korea has contributed 57 theses followed by Korean Science of Landscape Architecture with 10 theses and Korean Rural Society with 8 theses. Among them, Korean Rural Society is the only one continually contributing theses up until now, positioning itself at the center of rural landscape research. Second, a look into years shows that there was meager researches made; 6 from 1995 ~ 1999, 9 from 2000 to 2004 while there was a leap up to 55 from 2005 to 2009. There was a decrease down to 39 theses from 2010 to 2014 but research activities went on.

Retinal Function Analysis and Histopathologic Assessment after Intravitreal Cidofovir Injection in Normal Beagle Dogs

  • Park, Sungwon;Kang, Seonmi;Park, Sangwan;Han, Jiseok;Kim, Yongbum;Seo, Kangmoon
    • Journal of Veterinary Clinics
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    • v.34 no.5
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    • pp.341-346
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    • 2017
  • This study was performed to evaluate the effects of an intravitreal injection of cidofovir in beagle dogs. Nine beagle dogs (18 eyes) were used and randomly assigned to the following three groups of various dosages: 100, 500 and $1000{\mu}g$. Aqueous paracentesis was followed by an intravitreal injection of cidofovir. Intraocular pressure (IOP) was measured twice a week and electroretinography (ERG) and ophthalmoscopic examination were performed every week during the study. At the end of the study, all eyes were enucleated for histopathologic evaluation after euthanasia. The IOPs in the 500 and $1000{\mu}g$ groups were statistically lower than baseline with no significant IOP changes in the $100{\mu}g$ group. Reduced amplitudes of ERG recordings were identified in the eyes injected with higher dose groups than the $100{\mu}g$ group. Histopathologic examination revealed that there were dose-related toxicities to the ciliary body and the retina. These results suggest that intravitreal cidofovir had dose-dependent IOP lowering effects associated with ciliary body destruction, but had the potential to cause retinal toxicity in beagle dogs.