• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.585-589
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• 2008

Second-order rate constants (kN) have been measured for reactions of Y-substituted phenyl 2-thiophenecarboxylates (6a-h) with morpholine and piperidine in 80 mol % H2O/20 mol % DMSO at 25.0 0.1 oC. The Brnsted-type plot for the reactions of 6a-h with morpholine is linear with b lg = 1.29, indicating that the reactions proceed through a tetrahedral zwitterionic intermediate (T?). On the other hand, the Brnsted-type plot for the reactions of 6a-h with piperidine exhibits a downward curvature, implying that a change in the rate-determining step occurs on changing the substituent Y in the leaving group. Dissection of kN into microscopic rate constants (i.e., k1 and k2/k1 ratio) has revealed that k1 is smaller for the reactions of 6a-h than for those of Y-substituted phenyl 2-furoates (5a-h), while the k2/k1 ratio is almost the same for the reactions of 5a-h and 6a-h. It is also reported that modification of the nonleaving group from the furoyl (5a-h) to the thiophenecarbonyl (6a-h) does not influence pKao (defined as the pKa at the center of the Brnsted curvature) as well as the k2/k1 ratio.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.530-532
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• 2015

Nowadays, it is animately studied on IoT(Internet of Things) on the strength of development of the short-range communications technology and smart device. In this paper, it made a interface board which is capable of short-range communications networks based on embedded linux and Android OS (operating system). and we also made a IoT sensor module and device driver module. This devices are easily separated and changed and also simply embodied in IoT, and It was implemented using the Android app that allows you to control the sensors.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.297-302
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• 2002

The subsystems of two channel correlation radiometer such as RF front-end, IF and LF unit, LO unit, software based I/Q demodulator and complex correlator are characterized and their performance is analyzed in this paper. The limited hardware calibration method and receiver design consideration are discussed. The receiver architecture of 37GHz correlation radiometer is integrated. The designed radiometer employs a single-sideband superheterodyne receiver. The center frequency of the radiometer is 37 GHz and IF center frequency is 1.95 GHz with the equivalent noise bandwidth of 79.6 MHz. The receiver has less than 4.2 dB noise figure which is calculated by the Y-factor method and its gain can be adjusted from 60 dB to 80 dB.

• Research in Mathematical Education
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• v.14 no.4
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• pp.361-380
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• 2010

Some 400 Secondary One (i.e. seventh-grade) students from 10 schools were provided with non-routine mathematical problems in their normal mathematics classes as exercises for one academic year. Their attitudes toward mathematics, their conceptions of mathematics and their problem-solving performance were measured both in the beginning and at the end of the year. Hierarchical regression analyses revealed that the introduction of an appropriate dose of non-routine problems would generate some effects on the students' conceptions of mathematics. A medium dose of non-routine problems (as reported by the teachers) would result in a change of the students' conception of mathematics to perceiving mathematics as less of "a subject of calculables." On the other hand, a high dose would lead students to perceive mathematics as more useful and more as a discipline involving thinking. However, with a low dose of non-routine problems, students found mathematics more "friendly" (free from fear). It is therefore proposed that the use of non-routine mathematical problems to an appropriate extent can induce changes in students' "lived space" of mathematics learning and broaden their conceptions of mathematics and mathematics learning.

• ALGAE
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• v.34 no.2
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• pp.91-97
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• 2019

Chilean species of marine macroalgae with amphitropical distributions oftentimes result from introductions out of the Northern Hemisphere. This possibility was investigated using haplotype data in an amphitropical red macroalgae present in Chile, Callophyllis variegata. Published sequence records from Canada and the United States were supplemented with new collections from Chile (April 2014-November 2015). Specimens of C. variegata were amplified for the 5′ end of the cytochrome c oxidase subunit I gene (COI-5P) and the full length nuclear internal transcribed spacer region. Haplotype networks and biogeographic distributions were used to infer whether C. variegata was introduced between hemispheres, and several population parameters were estimated using IMa2 analyses. C. variegata displayed a natural amphitropical distribution, with an isolation time of approximately 938 ka between hemispheres. It is hypothesized that contemporary populations of C. variegata were established from a refugial population during the late Pleistocene, and may have crossed the tropics via rafting on buoyant species of kelp or along deep-water refugia coincident with global cooling, representing a rare case of a non-human mediated amphitropical distribution.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.903-920
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• 2020

Since its first demonstration as a practical genome editing tool in the early 2010s, the use of clustered regularly interspaced short palindromic repeat (CRISPR) along with the endonuclease Cas9 (CRISPR/Cas9) has become an essential choice for generating targeted mutations. Due to its relative simplicity and cost-effectiveness compared to other molecular scissors, i.e., zinc finger nuclease (ZFN) and transcription activator-like effector nuclease (TALEN), the CRISPR/Cas9 system has been shown to have a massive influence on genetic studies regardless of the biological kingdom. Although the system is in the process of being established, numerous protocols have already been released for the system and there have been various topics of CRISPR related papers published each year in ever-increasing manner. Here, we will briefly introduce CRISPR/Cas9 system and discuss the variants of the CRISPR system. Also, their applications to crop improvement will be dealt with mainly ornamental crops among horticultural crops other than Arabidopsis as a model plant. Finally, some issues on the barriers restraining the use of CRISPR system on floricultural crops, the prospect of CRISPR system as a DNA-free genome editing tool with efficient facilitators and finally, the future perspectives on the CRISPR system will be described.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.203-210
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• 2003

The purpose of this study is to investigate the pharmacokinetics and tissue distribution of recombinant bovine somatotropin (rBST) after subcutaneous adminstration of $^{125}I-rBST$ in male and female rats. A solid state conjugation (Iodo-bead$^{(R)}$) method was confirmed useful for producing $^{125}I-rBST$ because the administration of the conjugated form enabled enough to determine time- concentration relationships of rBST in rats. Subcuatenous administrations showed sex differences that female ($t_{1/2,kc}$, 2.87 h) revealed rapid elimination as compared to male ($t_{1/2,ke}$, 4.81 h), with the absorption ($t_{1/2,ka}$ in male being 0.3 h and that in female 0.75 h) in the reverse order. For subcutaneous administration of rBST in male rats, the liver was the highest in amount, followed by kidney, testes, muscle, and stomach, at the slaughtering tame of 1, 6, 12 and 24 h. But the testes was the highest at the 48 h slaughtered animals, followed by liver, kidney, stomach, and muscle. In slaughtered females at 1, 6, and 12 h after the administration of rBST, the liver was the highest, followed by ovary, kidney, small intestine, and stomach. At 24 and 48 h slaughtered female rats, the ovary was the highest, the liver the second, and the kidney the third.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9831-9834
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• 2014

Background: The prevalence of esophageal cancer (EC) with second primary cancers (SPC) is increasing worldwide. This study was aimed to understand the clinical features of EC patients with SPC in the Taiwanese population. Materials and Methods: Clinical and laboratory data for 180 EC patients with or without SPC were collected between January 2009 and December 2013. Information on treatment approaches, location of SPCs and ABO blood type were also collected and stratified. Results: The most common SPC in EC patients was hypopharyngeal cancer, followed by laryngeal cancer and hepatocellular carcinoma in our study. Malignancies of colon, prostate and lung were also found. There was a significant higher portion of blood type A in the EC patients with SPC compared with those without (42.4% vs 19.5%, P=0.006). Conclusions: The frequency and SPC site distribution and blood type A should be considered in clinical evaluation of EC patients with a high risk of developing SPC in the Taiwanese population.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.506-512
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• 1991

Monoclonal antibodies (mAb) to indole-3-acetic acid (IAA) were produced and characterized. Spleen cells from mouse immunized with IAA coupled to bovine serum albumin were fused with SP2/0-Ag14 myeloma cells. Three clones secreted specific antibodies to IAA were established to hybridoma cell lines and designated WLI-G1, WLI-G3 and WLI-Ell. The antibodies produced were classified into IgG, types and revealed the high degree of specificity by cross-reaction in the IAA derivatives and its analogues. In the IAA-ELISA with mAb, the measuring range of the assay was 1-500 p mol, and Ka and binding capacity calculated from Scatchard plot were 6.7 X 10$^{-10}$ L/M and 6 x 10$^{-10}$ L/M respectively. The ELISA with mAb can be used to quantitate IAA directly in crude plant eatract. The results showed that the immunoassay was easy and sensitive method to perform and applicate for quantitative analysis of IAA in plant.

• Membrane Journal
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• v.23 no.1
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• pp.80-91
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• 2013

Metal-templated condensation of cyclohexanedione dioxime and phenylboronic acid in the presence of Fe(II) sulfate heptahydrate proceeds cleanly in methanol to furnish the Fe(II) clathrochelate. An organic/inorganic hybrid membranes composed of Fe(II) clathrochelate and polyethersulfone was prepared by using phase inversion method. For membrane preparation, the Fe(II) clathrochelate was highly soluble (3~5 g/L) in DMF, NMP, and DMAc, which meets the requirements for the solubility of metal complexes in polar aprotic solvent used in membrane preparation. It was stable even in the presence of strong acids, such as trifluorosactic acid (pKa = 0.3). It was characterized by UV-vis spectroscopy, and their stability in solution phase studied in the presence of (i) strong acids or (ii) competing chelates. Organic/inorganic hybrid membranes were prepared with polyethersulfone, polyvinylpyrrolidone, p-toluenesulfonic acid, Fe(II) clathrochelate and DMF by using nonsolvent induced phase inversion method. The addition of Fe(II) clathrochelate leads increase of surface pore density, mean pore size and flux. We can obtain highly asymmetric membranes by addition of Fe(II) clathrochelate.