• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.3
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• pp.313-320
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• 2018

Chub mackerel Scomber japonicus is an economically important pelagic species in the western North Pacific. In the last 50 years, the annual total catch in Korean waters showed large fluctuations, ranging from 100 to $420{\times}10^3tons$. To provide a biological reference point for management of chub mackerel, we applied a simulation-based yield-per-recruit (Y/R) model that considered both temperature-dependent growth and size-dependent mortality. We estimated the fisheries yield with respect to varying biological reference points and environmental conditions, including 1) the instantaneous rate of fishing mortality (F), 2) length of fish at first capture ($L_c$), and 3) water temperature. The result of our analysis showed that the Y/R could be greatest when the $L_c$ ranges from 19-27 cm and F ranges from $1.48-2.00yr^{-1}$. Y/R increases with increased water temperature between 15 and $23^{\circ}C$. We suggest targeting an $L_c$ of 17 cm (age=0.6 years) under the assumed current of $F=0.48yr^{-1}$ for maximizing the chub mackerel harvest. Further analysis considering spawning and recruitment processes are required to provide biological reference points to ensure the sustainability of chub mackerel fisheries in Korean waters.

• Herbal Formula Science
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• v.28 no.1
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• pp.71-80
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• 2020

Obejectives : The purpose of this study was to investigate the effects of Yijin-tang on pacemaker potentials of small intestinal interstitial Cells of Cajal (ICC). Methods : To dissociate the ICC, we used enzymatic digestions from the small intestine in mice. The electrophysiological whole-cell patch-clamp configuration was used to record pacemaker potentials in the cultured ICC and the in vivo effects of Yijin-tang on GI motility were investigated by calculating percent intestinal transit rates (ITR). Results : 1. The ICC generated pacemaker potentials in the murine small intestine. Yijin-tang produced membrane depolarization with concentration-dependent manners in the current clamp mode. 2. Pretreatment with a Ca²⁺ free solution and thapsigargin, a Ca²⁺-ATPase inhibitor in the endoplasmic reticulum, stopped the pacemaker potentials. In the case of Ca²⁺-free solutions and thapsigargin, Yijin-tang did not induce membrane potential depolarizations. 3. U73122, a phospholipase C (PLC) inhibitors, blocked the Yijin-tang-induced membrane potential depolarizations. However, U73343, an inactive PLC inhibitors, did not block. 4. In the presence of protein kinase C (PKC) inhibitors, staurosporine or Rottlerin, Yijin-tang depolarized the pacemaker potentials. However, in the presence of Go6976, Yijin-tang did not depolarize the pacemaker potentials. 5. In mice, intestinal transit rate (ITR) values were significantly and dose-dependently increased by the intragastric administration of Yijin-tang. Conclusions : These results suggest that Yijin-tang can modulate the pacemaker activity of ICC through an internal/external Ca²⁺ and PLC/PKC-dependent pathway in ICC. In addition, Yijin-tang is a good candidate for the development of a prokinetic agent.

• The Journal of Korean Medicine
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• v.22 no.4
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• pp.10-21
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• 2001

Objective : To investigate the effect between Fructus Immaturus Ponciri (FIP, the immature fruit of Poncirus trifoliata) and Fructus Ponciri (FP, the ripe fruit of Poncirus trifoliata) on mast cell-mediated immediate-type allergic reactions. Methods : We performed anaphylactic reaction, histamine release, cAMP, $TNF-{\alpha}$, IgE. Results : The aqueous extract of FIP dose-dependently inhibited systemic and local allergic reaction was induced by compound 48/80 or anti-dinitrophenyl (DNP) IgE in a murine model. FIP also significantly inhibited mast cell-dependent ear swelling response induced by topical application of compound 48/80. When mice were orally pretreated with FIP, the plasma histamine levels were reduced in a dose-dependent manner. FIP dose-dependently inhibited histamine release from the rat peritoneal mast cells (RPMCs) was activated by compound 48/80 or anti-DNP IgE. The level of cAMP in RPMCs, when FIP was added, increased compared with that of a normal or control. In addition, FIP had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-a ($TNF-{\alpha}$) production from the RPMCs and IgE produced by lipopolysaccharide-stimulated murine whole spleen cells or U266B1 as human IgE-bearing B cells. However, FP showed the lower inhibition rate than those of FIP in above all allergic reactions. Conclusion : These data have important implications for our understanding of the clinical effects of FIP and FP on allergic diseases, and FIP is more effective than FP on the allergic reaction.

• Journal of Practical Engineering Education
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• v.6 no.1
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• pp.1-7
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• 2014

The variable control in the inductive inference for the confirmation and verification when the experimental data are collected is studied by applying the principle of probability inference. The control in engineering experiments is to protect any effect by of intervening variable except primary independent variable on the dependent variable. By the special condition the possibility for developing a phenomenon will be maximized; otherwise, by the extraneous condition the possibility for developing a phenomenon will be minimized. By doing so, the control may provide insurance for the causal relationship between the certain prior event (independent variable) and the post-event (the dependent variable). Some experiments by using both elliptical trainer and tread mill under the variable control are performed in order to find the relations between the energy expenditure, the respiratory exchange ratio (RER), and the heart rate (HR) against the exercise speed.

• The Korean Journal of Physiology
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• v.16 no.2
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• pp.177-186
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• 1982

The effect of ethacrynic acid (EA) on the renal secretion of PAH was examined in cat kidney. $C_{PAH}$ and $T_{PAH}$ were measured before and after infusion of EA $(0.5{\sim}50mg/kg)$ through the femoral vein. The following results were obtained: 1) In the dosage range of 0.5 to 25 mg/kg, EA increased the urine flow, and sodium and potassium excretion in dose-dependent manner, but the glomelular filtration rate was decreased as the dosage of EA was increased. 2) $C_{PAH}$ and $T_{PAH}$ were decreased by EA in the dosage range of 3 to 25 mg/kg and 1 to 50 mg/kg, respectively, in dose·dependent manner with the dosage to cause 50% inhibition of about 5 mg/kg. 3) With dosage of 0.5mg/kg, EA appeared to exert a great effect on diuretic response without the influence on $T_{PAH}$. At 10min after infusion of EA, a potent diuretic effect appeared, while $T_{PAH}$ did not show a significant change. These results suggest that the action mechanism of EA on tubular secretion of PAH may be different from that on natriuresis. 4) With dosage of 5 mg/kg, EA did not inhibit the Na-K-ATPase activity in microsomal fractions from both cortex and medulla. 5) The double reciprocal plot ($l/T_{PAH}$ versus $l/P_{PAH}$) suggested that EA inhibited the P AH secretion by a competitive pattern. However, probenecid, a prototypic inhibitor of the organic acid pump, had no influence on both the inhibitory effect of $T_{PAH}$ and the natriuretic effect by EA. These results suggest that in vivo EA altered tubular secretion of P AH through interactions with receptors that are not identical with the Na-K-ATPase.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.249-258
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• 2007

Experiments were conducted with aims to (1) estimate the biomass yield potential, (2) characterize the biomass and digestible dry matter production, and (3) reveal the characteristic seedling establishment of a whole crop rice variety, Nogyangbyeo, in dry- and wet-seeded rice. Maximum aboveground total biomass of Nogyangbyeo was 18 t $ha^{-1}$ in dry-seeded rice and 20 t $ha^{-1}$ in wet-seeded rice. Biomass yield potential of Nogyangbyeo was lower than that of Dasanbyeo. Comparatively, Nogyangbyeo was straw-dependent and Dasanbyeo was grain-dependent for biomass accumulation. Percentage of digestible dry matter (DDM) was higher in panicles than straw. Digestible dry matter yield was determined mainly by biomass yield rather than DDM percentage. Number of seedling establishment in Nogyangbyeo was $73m^{-2}$ in dry-seeded rice and $109m^{-2}$ in wet-seeded rice. Poor seedling establishment of dry-seeded Nogyangbyeo in the field condition was the result of low seed germination under low temperature and poor seedling emergence by deep sowing. Low seedling emergence rate of Nogyangbyeo was attributed mainly to slow elongation growth by slow leaf development and partly to mesocotyl and 1st internode lengths, not to genetically defined leaf length. The slow elongation growth of Nogyangbyeo was the same even in the high daily mean temperature of $24^{\circ}C$. Results suggest DDM yield in rice can be improved simply by increasing biomass and whole crop rice varieties should be adaptable to direct-seeding.

• Applied Microscopy
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• v.36 no.4
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• pp.291-297
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• 2006

To evaluate the effects of ingestion of alcoholic drinks on the toxicities of industrial compounds, cyclohexane (CH) was intraperitoneally administrated to rats (1.56g/kg body weight), which had been ingested 15% ethanol for up to 6 weeks,4 times by once a day and every other day. Following the last treatment of ethanol or CH, blood and liver tissues were collected after 4 hours prior to sacrifice of animals. By the injection of CH, liver weight (% of body weight) and xanthine oxidase activity in serum were increased, and glucose-6-phasphatase (G6P) activity in liver was decreased compared to them of control group. The activities of CH metabolizing enzymes, such as cytochrome P450 dependent aniline hydroxylase (CYPdAH) and alcohol dehydrogenase (ADH), were significantly increased by injection of CH, and those activities were the highest in CH-injected group after pretreated with alcohol. Ultrastructurally. both of alcohol treatment and CH injection induced transforming into the smooth-endoplasmic reticulum from rough-endoplasmic reticulum, the those rate was the highest in case of CH-injection after pretreated with alcohol. From these results, it is suggested that alcohol intake on a level without alcoholic degeneration of hepatocytes could enhance the CH metabolism of liver.

• Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.10.1-10.10
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• 2020

Background: Butaphosphan (BTP) has recently been introduced into the Korean aquaculture sector as a stressattenuating agent. In this study, a sensitive chemical analytical method was established for the detection of BTP in the olive flounder (Paralichthys olivaceus) tissues. Methods: Utilizing a method employing liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), detection sensitivity, specificity, and precision were satisfactorily established. Temporal changes in the BTP plasma and muscle concentrations were assessed after a single intramuscular injection of BTP (50 and 150 mg/kg) to the olive flounder maintained at 13 ℃ or 22 ℃. Results: High BTP plasma levels were achieved immediately after the injection, and the drug was rapidly eliminated. Additionally, plasma BTP levels were markedly dependent on the elimination rate, which, in turn, seemed dependent on the water temperature, with the drug elimination half-life and mean residence time significantly shorter at 22 ℃ than 13 ℃. Overall, muscle BTP levels were markedly lower than the plasma levels. Notably, muscle levels were not influenced by water temperatures. Muscle BTP concentrations were used to estimate the necessary withdrawal period for drugs used in food fish, with BTP levels maintained far below the possible hazardous limit. Conclusions: In conclusion, the established LC-MS/MS method can be used for BTP residue detection with high sensitivity and reproducibility.

• Journal of Korea Game Society
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• v.13 no.4
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• pp.15-24
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• 2013

The game of Go, which is originated at least more than 2,500 years ago, is one of the oldest board games in the world. So far the theoretical studies concerning to the Go openings are still insufficient. We applied traditional LDA algorithm to recognize a pro player's opening to a class obtained from the training openings. Both class-independent LDA and class-dependent LDA methods are conducted with the Go game records of the Korean top 10 professional Go players. Experimental result shows that the average recognition rate of class-independent LDA is 14% and class-dependent LDA 12%, respectively. Our research result also shows that in contrary to our common sense the algorithm based on PCA outperforms the algorithm based on LDA and reveals the new fact that the Euclidean distance metric method rarely does not inferior to LDA.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.2
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• pp.101-109
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• 2012

Objectives: The inactivation of the tumor suppressor gene $p16^{INK4a}$ plays an important role in the development of malignant tumors, including oral squamous cell carcinoma. The p16 gene is involved in the p16/cyclin-dependent kinase/retinoblastoma (Rb) gene pathway of cell cycle control. The p16 protein is considered a negative regulator of this pathway. The p16 gene encodes an inhibitor of cyclin-dependent kinases 4 and 6 which regulate the phosphorylation of the retinoblastoma gene and G1 to S phase transition in the cell cycle. However, the p16 gene can lose its functionality through point mutations, loss of heterozygosity or methylation of its promoter region. Materials and Methods: In this study, the authors analyzed the correlation between various clinicopathological findings- patient age, gender and smoking, disease recurrence, tumor size, stage, and differentiation- and p16 protein expression or p16 promoter hypermethylation in 59 cases of head and neck squamous cell carcinoma. Results: The results revealed p16 protein expression and p16 promoter hypermethylation in 28 cases (47.5%) and 21 cases (35.6%), respectively, of head and neck squamous cell carcinoma. However, neither p16 protein expression nor p16 promoter hypermethylation had any statistical influence on clinicopathological findings or survival rate. Conclusion: This data, and a review of the literature, suggest that p16 promoter hypermethylation cannot yet be used as an independent prognostic factor influencing carcinogenesis, but must be considered as an important factor along with other genetic alterations affecting the pRb pathway.