• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• Cross-Cultural Studies
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• v.24
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• pp.170-183
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• 2011

This study explored how a Chinese college student who previously had not reached a threshold level of Korean proficiency used L1 (Chinese) and L2 (English) as a tool to socialize into Korean (L3) culture of learning over the course of study. From a perspective of language socialization, this study examined the cross-linguistic influence of L1 and L2 on the L3 acquisition process by tracing an approach to language learning and practices taken by the Chinese student as a case study. Data were collected through three methods; interview protocols, various types of written texts, and observations. The results showed that the student used English as a means to negotiate difficulties and expertise by empowering her L2 exposure during the classroom practices. Her ways of using L2 in oral practices could be characterized as the 'Inverse U-shape' pattern, under which she increased L2 exposure at the early stage of the study and shifted the intermediate language to L3 at the later stage of the study. When it comes to the language use in written practices, the sequence of "L2-L1-L3" use gradually changed to the "L2-L3" sequence over time, signifying the importance of interaction between L2 and L3. However, the use of her native language (L1) in a Korean-speaking classroom was limited to a certain aspect of literacy practices (i.e., vocabulary learning or translation). This study argues for L2 communication channel in cross-cultural classrooms as a key factor to determine sustainable learning growth.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.286-293
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• 2012

The resistance to Tobamovirus in Capsicum spp. has been known to be controlled by five different alleles ($L^0$, $L^1$, $L^2$, $L^3$, and $L^4$) of L locus on the telomere of long arm of pepper chromosome 11. To develop a set of molecular markers differentiating all the alleles of L locus, we used five pepper differential hosts including Capsicum annuum Early California Wonder (ECW, $L^0L^0$), C. annuum Tisana ($L^1L^1$), C. annuum Criollo de Morelos 334 (CM334, $L^2L^2$), Capsicum chinense PI 159236 ($L^3L^3$), and Capsicum chacoense PI 260429 ($L^4L^4$). Developing a series of CAPS or SCAR markers specifically linked to the alleles was allowed by the sequence comparison of PCR amplicons of the $L^3$-linked markers (189D23M, A339, and 253A1R) and BAC sequences (FJ597539 and FJ597541) in the pepper differentials. Genotypes deduced by these markers in 48 out of 53 $F_1$ hybrids of commercial pepper varieties were consistent with their phenotypes by bioassay using Tobamovirus pathotypes ($P_0$, $P_1$, and $P_{1,2$). Consequently, these markers can be useful to differentiate L alleles and for breeding Tobamovirus resistance in pepper with marker-assisted selection.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.67-76
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• 1997

The occurrence of multidrug resistance (MDR) is one of the main obstacles in the successful chemotherapeutic treatment of cancer. In this study The gene expressions of multidrug resistance-associated protein (MRP), c-myc and c-fos were investigated in L1210 cells. Adriamycin- or vincristine-resistant L1210 cells, L1210AdR or L1210VcR, respectively, has been identified to overexpression of mdr1 gene. The expression leve of MRP gene in L1210AdR and L1210Cis was more decreased than that in L1210 cells. The c-myc and c-fos genes were expressed both in L1210 and resistant sublines. In L1210AdR, the expressions level of c-myc and c-fos genes were decreased than in L1210. However, in L1210VcR and L1210Cis, c-myc and c-fosgene expressionwere rather increased than L1210. These results suggested that MRP does not contribute in resistance of drug-resistant L1210 cells and there is no relations between MRP and mdr1 gene expression. The expression of c-myc and c-fos gene may be changed during transformation of L1210 to drug-resistant sublines.

• The Journal of Korean Medicine
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• v.24 no.1
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• pp.141-154
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• 2003

Objectives : This study was undertaken to define the effect of Diospyros kaki L. Radix or Diospyros kaki L. Folium on phenylephrine-induced arterial contraction and the mechanism of Diospyros kaki L. Radix or Diospyros kaki L. Foliuminduced relaxation. Methods : In order to investigate the effect of Diospyros kaki L. Radix or Diospyros kaki L. Folium on contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. Diospyros kaki L. Radix or Diospyros kaki L. Folium extract was infused into contracted arterial strips induced by phenylephrine. To analyze the mechanism of Diospyros kaki L. Radix or Diospyros kaki L. Folium-induced relaxation, Diospyros kaki L. Radix or Diospyros kaki L. Folium extract was infused into contracted arterial strips induced by phenylephrine after treatment with indomethacin, $N{\omega}-nitro-L-arginine$, methylene blue or tetraethylammonium chloride, and $Ca^{2+}$ was infused into contracted arterial strips induced by phenylephrine after treatment of Diospyros kaki L. Radix or Diospyros kaki L. Folium in a $Ca^{2+}$-free solution. Results : Diospyros kaki L. Radix or Diospyros kaki L. Folium showed relaxation effect on arterial strip with endothelium contracted by phenylephrine, but in the strips without endothelium, Diospyros kaki L. Radix or Diospyros kaki L. Folium-induced relaxation was significantly inhibited. The endothelium-dependent relaxation induced by Diospyros kaki L. Radix or Diospyros kaki L. Folium was decreased by pretreatment with $N{\omega}-nitro-L-arginine$ or methylene blue but it was not observed in the strips pretreated with indomethacin or tetraethylammonium chloride. When $Ca^{2+}$ was applied to the strips which were contracted by phenylephrine in a $Ca^{2+}$-free solution, arterial contraction was increased. However, pretreatment with Diospyros kaki L. Radix or Diospyros kaki L. Folium inhibited contractile response to $Ca^{2+}$. Conclusions : Diospyros kaki L. Radix or Diospyros kaki L. Folium may suppress influx of extra- cellular $Ca^{2+}$ through the formation of nitric oxide in the vascular endothelial cells.

• Korean Journal of Plant Taxonomy
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• v.38 no.1
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• pp.17-29
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• 2008

Phylogenetic relationships were examined for 17 taxa of Lycoris by RAPD analysis. The length of the amplified DNA fragments ranged from 300 bp to 1,700 bp. 57 scorable RAPD markers were observed from PCR reactions with five random oligoprimers. The analysis by UPGMA sepatated the examined taxa of Lycoris into were clusters. First group was comprised of ten taxa of L. chinensis var. sinuolata, L. sanguinea var. koreana, L. uydoensis, L. flavescens, L. radiata var. pumila, L. radiata, L. squamigera, L. chejuensis, L. aurea and L. guangxiensis, second group of L. haywardii, L. sprengeri, L. rosea, L. straminea and L. houdyshii, third group of outgroup of Narcissus tazetta var. chinensis and Crinum asiaticum var. japonicum. From the viewpoint of cytological characters such as polyploidy and karyotype, the RAPD analysis was very useful to show the relationship among the intraspecific taxa of Lycoris.

• Food Science and Preservation
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• v.14 no.2
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• pp.188-193
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• 2007

The purpose of this study was to isolate lactic acid bacteria, useful in the fermentation industry from Hahyangju Nuruk. Five strains were isolated, and identified as Lactobacillus based on growth inhibition by 10% (v/v) alcohol at pH 4.0. Isolated strains were identified to species, and named Lactobacillus plantarum L-3, L. sakei L-10, and L. curvatus strains L-8, L-11, and L-12. Morphological characteristics, physiological data, carbohydrate fermentation patterns, and 16S rRNA sequence data, were all used to characterize the bacterial isolates. L. plantarum L-3 showed the highest lactic acid productivity of all isolates, but grew only poony in the presence of 10% (v/v) alcohol at pH 4.0. The other strains exhibited lower lactic acid productivity than did L. plantarum L-3 and did not grow in the presence of 10% (v/v) alcohol at pH 4.0. The optimal temperature and pH for lactic acid production were $30^{\circ}C$ and pH 6.0 7.0, respectively. The lactic acid productivity of L. plantarum L-3, L. sakei L-10 and the three L. curvatus strains L-8, L-11, and L-12 were (% v/v of culture supematant) 1.55, 1.0, 1.06, 1.0, and 0.99, respectively, at $30^{\circ}C$ and pH 6.0. While L. plantarum L-3 suffered growth inhibition in the presence of 10% (v/v) alcohol, growth of the other strains was inhibited at 8% (v/v) alcohol.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.3
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• pp.283-288
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• 2011

In this paper, an adaptive signal tracking loop for a GPS L1/L2C/L5 receiver is designed. The design parameters is adjusted according to the receiver's operating conditions such as the signal strength and the receiver dynamics by using the different characteristics of GPS L1, L2C and L5 signal. Simulation results show that the tracking accuracy of the proposed signal tracking loop is better than those of L1, L2C and L5 only signal tracking loop.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.2
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• pp.115-127
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• 2009

In the present paper we introduce and study L-pre-$T_0$-, L-pre-$T_1$-, L-pre-$T_2$ (L-pre-Hausdorff)-, L-pre-$T_3$ (L-pre-regularity)-, L-pre-$T_4$ (L-pre-normality)-, L-pre-strong-$T_3$-, L-pre-strong-$T_4$-, L-pre-$R_0$-, L-pre-$R_1$-separation axioms in (2, L)-topologies where L is a complete residuated lattice.Sometimes we need more conditions on L such as the completely distributive law or that the "$\bigwedge$" is distributive over arbitrary joins or the double negation law as we illustrate through this paper. As applications of our work the corresponding results(see[1,2]) are generalized and new consequences are obtained.

• Korean Journal of Veterinary Research
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• v.12 no.1
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• pp.91-95
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• 1972

Investigation of leptospiral antibody in Korean cattle and pigs was carried out from February to October, 1971. Ten different living antigens, namely L. icterohaemorrhagiae, L. canicola, L. antumnalis, L. hebdomadis, L. australis A, L. pomona, L. pyrogenes, L. grippotyphosa, L. bataviae and L. javanica, were used. A total of 590 Korean cattle and 460 pig blood samples collected from Seoul Majang-dong slaughterhouse were tested by the rapid microscopic agglutination test. Throughout the studies the following results were obtained and summarized. 1. Of 590 serum samples of Korean cattle 51 were positive(8.64%). 2. Of 460 serum samples of pigs 27 were positive (5.87%). 3. Of 51 positive cattle samples, 29(4.92%) showed antibody to a serotype of L. icterohaemorrhagiae and 18(3.0%) to L. canicola, and 4 (0.68%) to L. pomona. Eight of L. icterohaemorrhagiae positive samples showed a cross reaction to L. canicola. 4. Of 27 positive pig samples, 14(3.04%) showed antibody to L. ictereohaemorrhagiae and 7(1.52%) to L. grippotyphosa. 4(0.87%) to L. canicola, 2(0.43%) to L. pomona. Two of L. canicola positive samples showed a cross reaction to L. grippotyphosa. 5. Serum samples of seven pigs, showing antibody positive to L. grippotyphosa were first observed in Korea. 6. Infection rate of bovine and porcine leptospirosis, in Korea, appeared to be lower than that of Japan, Taiwan, Thailand and the Philippines.