식물체로부터 추출한 물질이 상추 종자의 발아 및 생장에 미치는 영향

박건남,이민경,황선주,김학윤,이인중,신동현,김길웅 경북대학교 농업과학기술연구소 1999 慶北大農學誌 Vol.17 No.-

This study was conducted to detect the allelopathic effect of water and ethanol extracts from 4 plant species (Lactuca sativa L., Ambrosia elatior L., Oenothenra odorata Jasp., Ginkgo biloba L.) on germination and growth of lettuce seeds. A little bit higher inhibitory effect was obtained in ethanol extracts rather than water extracts. Allelopathic effects varied in the source of extracts and concentrations of 4 plant species and the highest allelopathic effect appeared in 10% solution, regardless of plant species.

Study on Electrical Characteristics of FDM Conductive 3D Printing According to Annealing Conditions

Sun Kon Lee(이선곤),Yong Rae Kim(김용래),Tae Jung Yoo(유태정),Ji Hye Park(박지혜),Joo Hyung Kim(김주형) 한국기계가공학회 2018 한국기계가공학회지 Vol.17 No.6

In this paper, the effect of different 3D printing parameters including laminated angle and annealing temperature is observed their effect on FDM conductive 3D printing. In FDM 3D printing, a conductive filament is heated quickly, extruded, and then cooled rapidly. FDM 3D Print conductive filament is a poor heat conductor, it heats and cools unevenly causing the rapid heating and cooling to create internal stress. when the printed conductive specimens this internal stress can be increase electrical resistance and decrease electrical conductivity. Therefore, This experiment would like to use annealing to remove internal stress and increase electrical conductivity. The result of experiment when 3D printing conductive specimen be oven cooling of annealing temperature 120℃ electrical resistance appeared decrease than before annealing. So We have found that 3D printing annealing removes internal stresses and increases the electrical conductivity of printed specimens. These results are very useful for making conductive 3D printing electronic circuit, sensor ect...with electrical conductance suitable for the application.

Estimating the Important Components in Three Different Sample Types of Soybean by Near Infrared Reflectance Spectroscopy

Lee, Ho-Sun,Kim, Jung-Bong,Lee, Young-Yi,Lee, Sok-Young,Gwag, Jae-Gyun,Baek, Hyung-Jin,Kim, Chung-Kon,Yoon, Mun-Sup The Korean Society of Crop Science 2011 한국작물학회지 Vol.56 No.1

This experiment was carried out to find suitable sample type for the more accurate prediction and non-destructive way in the application of near infrared reflectance spectroscopy (NIRS) technique for estimation the protein, total amino acids, and total isoflavone of soybean by comparing three different sample types, single seed, whole seeds, and milled seeds powder. The coefficient of determination in calibration ($R^2$) and coefficient of determination in cross-validation (1-VR) for three components analyzed using NIRS revealed that milled powder sample type yielded the highest, followed by single seed, and the whole seeds as the lowest. The coefficient of determination in calibration for single seed was moderately low($R^2$ 0.70-0.84), while the calibration equation developed with NIRS data scanned with whole seeds showed the lowest accuracy and reliability compared with other sample groups. The scatter plot for NIRS data versus the reference data of whole seeds showed the widest data cloud, in contrary with the milled powder type which showed flatter data cloud. By comparison of NIRS results for total isoflavone, total amino acids, and protein of soybean seeds with three sample types, the powder sample could be estimated for the most accurate prediction. However, based from the results, the use of single bean samples, without grinding the seeds and in consideration with NIRS application for more nondestructive and faster prediction, is proven to be a promising strategy for soybean component estimation using NIRS.

Application of Near-Infrared Reflectance Spectroscopy (NIR) Method to Rapid Determination of Seed Protein in Coarse Cereal Germplasm

Lee, Young-Yi,Kim, Jung-Bong,Lee, Ho-Sun,Lee, Sok-Young,Gwag, Jae-Gyun,Ko, Ho-Cheol,Huh, Yun-Chan,Hyun, Do-Yoon,Kim, Chung-Kon The Korean Society of Crop Science 2010 Korean journal of crop science Vol.55 No.4

Kjeldahl method used in many materials from various plant parts to determine protein contents, is laborious and time-consuming and utilizes hazardous chemicals. Near-infrared (NIR) reflectance spectroscopy, a rapid and environmentally benign technique, was investigated as a potential method for the prediction of protein content. Near-infrared reflectance spectra(1100-2400 nm) of coarse cereal grains(n=100 for each germplasm) were obtained using a dispersive spectrometer as both of grain itself and flour ground, and total protein contents determined according to Kjeldahl method. Using multivariate analysis, a modified partial least-squares model was developed for prediction of protein contents. The model had a multiple coefficient of determination of 0.99, 0.99, 0.99, 0.96 and 0.99 for foxtail millet, sorghum, millet, adzuki bean and mung bean germplasm, respectively. The model was tested with independent validation samples (n=10 for each germplasm). All samples were predicted with the coefficient of determination of 0.99, 0.99, 0.99, 0.91 and 0.99 for foxtail millet, sorghum, millet, adzuki bean and mung bean germplasm, respectively. The results indicate that NIR reflectance spectroscopy is an accurate and efficient tool for determining protein content of diverse coarse cereal germplasm for nutrition labeling of nutritional value. On the other hands appropriate condition of cereal material to predict protein using NIR was flour condition of grains.

Manufacturing Experiments using FDM 3D-printed Flexible Resistance Sensors with Heterogeneous Polymer Material Annealing

Sun Kon Lee(이선곤),Young Chan Oh(오영찬),Joo Hyung Kim(김주형) 한국기계가공학회 2020 한국기계가공학회지 Vol.19 No.1

In this paper, the performances of the electrical characteristics of the Fused Deposition Modeling (FDM) 3D-printed flexible resistance sensor was evaluated. The FDM 3D printing flexible resistive sensor is composed of flexible-material thermoplastic polyurethane and a conductive PLA (carbon black conductive polylactic acid) polymer. While 3D printing, polymer filaments heat up quickly before being extruded and cooled down quickly. Polymers have poor thermal conductivity so the heating and cooling causes unevenness, which then results in internal stress on the printed parts due to the rapidity of the heating and cooling. Electrical resistance measurements show that the 3D-printed flexible sensor is unstable due to internal stress, so the 3D-printed flexible sensor resistance curve does not match the increases and decreases in the displacement curve. Therefore, annealing was performed to eliminate the mismatch between electrical resistance and displacement. Annealing eliminates residual stress on the sensor, so the electrical resistance of the sensor increases and decreases in proportion to displacement. Additionally, the resistance is lowered in comparison to before annealing. The results of this study will be very useful for the fabrication of various devices that employ 3D-printed flexible sensor that have multiple degrees of freedom and are not limited by size and shape.

Genomic Diversity of Helicobacter pylori

Lee, Woo-Kon,Choi, Sang-Haeng,Park, Seong-Gyu,Choi, Yeo-Jeong,Choe, Mi-Young,Park, Jeong-Won,Jung, Sun-Ae,Byun, Eun-Young,Song, Jae-Young,Jung, Tae-Sung,Lee, Byung-Sang,Baik, Seung-Chul,Cho, Myung-Je The Korea Society for Microbiology 1999 大韓微生物學會誌 Vol.34 No.6

Helicobacter pylori is a causative agent of type B gastritis and plays a central role in the pathogenesis of gastroduodenal ulcer and gastric cancer. To elucidate the host-parasite relationship of the H. pylori infection on the basis of molecular biology, we tried to evaluate the genomic diversity of H. pylori. An ordered overlapping bacterial artificial chromosome (BAC) library of a Korean isolate, H. pylori 51 was constructed to set up a genomic map. A circular physical map was constructed by aligning ApaI, NotI and SfiI-digested chromosomal DNA. When the physical map of H. pylori 51 was compared to that of unrelated strain, H. pylori 26695, completely different restriction patterns were shown. Fifteen known genes were mapped on the chromosome of H. pylori 51 and the genetic map was compared with those of strain 26695 and J99, of which the entire genomic sequences were reported. There were some variability in the gene location as well as gene order among three strains. For further analysis on the genomic diversity of H. pylori, when comparing the genomic structure of 150 H. pylori Korean isolates with one another, genomic macrodiversity of H. pylori was characterized by several features: whether or not susceptible to restriction digestion of the chromsome, variation in chromosomal restriction fingerprint and/or high frequency of gene rearrangement. We also examined the extent of allelic variation in nucleotide or deduced amino acid sequences at the individual gene level. fucT, cagA and vacA were confirmed to carry regions of high variation in nucleotide sequence among strains. The plasticity zone and strain-specific genes of H. pylori 51 were analyzed and compared with the former two genomic sequences. It should be noted that the H. pylori 51-specific sequences were dispersed on the chromosome, not congregated in the plasticity zone unlike J99- or 26695-specific genes, suggesting the high frequency of gene rearrangement in H. pylori genome. The genome of H. pylori 51 shows differences in the overall genomic organization, gene order, and even in the nucleotide sequences among the H. pylori strains, which are far greater than the differences reported on the genomic diversity of H. pylori.

Targeted Chemo-Photothermal Treatments of Rheumatoid Arthritis Using Gold Half-Shell Multifunctional Nanoparticles

Lee, Sun-Mi,Kim, Hyung Joon,Ha, You-Jung,Park, Young Nyun,Lee, Soo-Kon,Park, Yong-Beom,Yoo, Kyung-Hwa American Chemical Society 2013 ACS NANO Vol.7 No.1

<P>We have developed RGD-attached gold (Au) half-shell nanoparticles containing methotrexate (MTX) for the treatment of rheumatoid arthritis (RA), where MTX is the most widely used disease-modifying anti-rheumatic drug (DMARD) for the treatment of RA, and RGD peptide is a targeting moiety for inflammation. Upon near-infrared (NIR) irradiation, heat is locally generated due to Au half-shells, and the drug release rate is enhanced, delivering heat and drug to the inflamed joints simultaneously. RA is a chronic inflammatory disease characterized by synovial inflammation in multiple joints within the penetration depth of NIR light. When combined with NIR irradiation, these nanoparticles containing a much smaller dosage of MTX (1/930 of MTX solution) showed greater therapeutic effects than that of a conventional treatment with MTX solution in collagen-induced arthritic mice. This novel drug delivery system is a good way to maximize therapeutic efficacy and minimize dosage-related MTX side effects in the treatment of RA. Furthermore, these multifunctional nanoparticles could be applied to other DMARDs for RA or other inflammatory diseases.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-1/nn301215q/production/images/medium/nn-2012-01215q_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn301215q'>ACS Electronic Supporting Info</A></P>

Fused Deposition Modeling 3D Printing-based Flexible Bending Sensor

Sun Kon Lee(이선곤),Young Chan Oh(오영찬),Joo Hyung Kim(김주형) 한국기계가공학회 2020 한국기계가공학회지 Vol.19 No.1

Recently, to improve convenience, flexible electronics are quickly being developed for a number of application areas. Flexible electronic devices comprise characters such as being bendable, stretchable, foldable, and wearable. Effectively manufacturing flexible electronic devices requires high efficiency, low costs, and simple processes for manufacturing technology. Through this study, we enabled the rapid production of multifunctional flexible bending sensors using a simple, low-cost Fused Deposition Modeling (FDM) 3D printer. Furthermore, we demonstrated the possibility of the rapid production of a range of functional flexible bending sensors using a simple, low-cost FDM 3D printer. Accurate and reproducible functional materials made by FDM 3D printers are an effective tool for the fabrication of flexible sensor electronic devices. The 3D-printed flexible bending sensor consisted of polyurethane and a conductive filament. Two patterns of electrodes (straight and Hilbert curve) for the 3D printing flexible sensor were fabricated and analyzed for the characteristics of bending displacement. The experimental results showed that the straight curve electrode sensor sensing ability was superior to the Hilbert curve electrode sensor, and the electrical conductivity of the Hilbert curve electrode sensor is better than the straight curve electrode sensor. The results of this study will be very useful for the fabrication of various 3D-printed flexible sensor devices with multiple degrees of freedom that are not limited by size and shape.

A Putative Cold Shock Protein-encoding Gene Isolated from Arthrobacter sp. A2-5 Confers Cold Stress Tolerance in Yeast and Plants

Lee, Seong-Kon,Park, Sung-Han,Lee, Jeong-Won,Lim, Hae-Min,Jung, Sun-Young,Park, In-Cheol,Park, Soo-Chul The Korean Society for Applied Biological Chemistr 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.6

A putative cold shock protein gene, designated as ArCspA, was isolated from Arthrobacter sp. A2-5 extracted from soil at the South Pole. The ArCspA gene is 873 nucleotide bp long and includes a 207-bp short open reading frame (ORF) with 49.3-92% amino acid identity to peptide sequences of other bacterial cold shock proteins. Northern blot analysis revealed that ArCspA was highly expressed at low temperatures. Bio-functional analysis using ArCspA-overexpressed transgenic Saccharomyces cerevisiae showed that ArCspA conferred cold tolerance on yeast at low temperatures ($15^{\circ}C$). We then developed an ArCspA-overexpressed transgenic tobacco line to determine whether ArCspA is also functional in plants. After cold treatment at $-25^{\circ}C$C for 90 min followed by recovery for 4 weeks at 25oC, 17 transgenic lines survived at a high rate (60.0%), whereas under the same treatment conditions, wild-type plants did not survive. We also found that progeny of transgenic tobacco plants subjected to freezing stress at $-20^{\circ}C$ had significantly higher seed germination ability than wild-type plants. These results clearly indicate that the ArCspA protein plays an important role in cold tolerance in both yeast and plants.

Coffee-Driven Green Activation of Cellulose and Its Use for All-Paper Flexible Supercapacitors

Lee, Donggue,Cho, Yoon-Gyo,Song, Hyun-Kon,Chun, Sang-Jin,Park, Sang-Bum,Choi, Don-Ha,Lee, Sun-Young,Yoo, JongTae,Lee, Sang-Young American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.27

<P>Cellulose, which is one of the most-abundant and-renewable natural resources, has been extensively explored as an alternative substance for electrode materials such as activated carbons. Here, we demonstrate a new class of coffee-mediated green activation of cellulose as a new environmentally benign chemical-activation strategy and its potential use for all-paper flexible supercapacitors. A piece of paper towel is soaked in espresso coffee (acting as a natural activating agent) and then pyrolyzed to yield paper-derived activated carbons (denoted as 'EK-ACs'). Potassium ions (K+), a core ingredient of espresso, play a viable role in facilitating pyrolysis kinetics and also in achieving a well-developed microporous structure in the EK-ACs. As a result, the EK-ACs show significant improvement in specific capacitance (131 F g(-1) at a scan rate of 1.0 mV s(-1)) over control ACs (64 F g(-1)) obtained from the carbonization of a pristine paper towel. All-paper flexible supercapacitors are fabricated by assembling EKACs/carbon nanotube mixture-embedded paper towels (as electrodes), poly(vinyl alcohol)/KOH mixture-impregnated paper towels (as electrolytes), and polydimethylsiloxane-infiltrated paper towels (as packaging substances). The introduction of the EKACs (as an electrode material) and the paper towel (as a deformable and compliant substrate) enables the resulting all-paper supercapacitor to provide reliable and sustainable cell perforinance as well as exceptional mechanical flexibility. Notably, no appreciable loss in the cell capacitance is observed after repeated bending (over 5000 cycles) or multiple folding. The coffee mediated green activation of cellulose and the resultant all-paper flexible supercapacitors open new material and system opportunities for eco-friendly high-performance flexible power sources.</P>