• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.963-974
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• 2015

This study was conducted to determine the effects of organic vegetable cultivation on the soil physical properties in 33 farmlands under plastic greenhouse in Korea. We were investigated 5~8 farms per organic vegetable crops during the period from August to November 2014. The main cultivated vegetables were leafy lettuce (Lactuca sativa L.), Perilla leaves (Perilla frutescens var. Japonica Hara), cucumber (Cucumis sativus L.), strawberry (Fragaria ananassa L.) and tomato (Lycopersicon spp.). We have analyzed soil physical properties. The measured soil physical parameters were soil plough layer, soil hardness, penetration resistance, three soil phase, bulk density and Porosity. The measurement of the soil plough layer, soil hardness and penetration resistance were carried out direct in the fields, and the samples for other parameters were taken using the soil core method with approximately 20 mm diameter core collected from each organic vegetable field. Soil plough layer was average 36 cm and ranged between 30 and 50 cm, and slightly different depending on the sorts of vegetable cultivation. The soil hardness was $0.17{\pm}0.15{\sim}1.34{\pm}1.02$ in the topsoil, $0.55{\pm}0.34{\sim}1.15{\pm}0.62$ in the subsoil. It was not different between topsoil and subsoil, but showed a statistically significant difference between the leafy and fruit vegetables. Penetrometer resistance is one of the important soil physical properties that can determine both root elongation and yield. The increase in density under leafy vegetables resulted in a higher soil penetrometer resistance. Soil is a three-component system comprised of solid, liquid, and gas phases distributed in a complex geometry that creates large solidliquid, liquid-gas, and gas-solid interfacial areas. The three soil phases were dynamic and typically changed in organic vegetable soils under greenhouse. Porosity was characterized as range of $54.2{\pm}2.2{\sim}60.3{\pm}2.4%$. Most measured soils have bulk densities between 1.0 and $1.6gcm^{-3}$. To summarize the above results, Soil plough layer has been deepened in organic vegetable cultivation soils. Solid hardness (the hardness of the soil) and bulk density (suitable for the soil unit mass) have been lowered. Porosity (soil spatial content) was high such as a well known in organic farmlands. Important changes were observed in the physical properties according to the different vegetable cultivation. We have demonstrated that the physical properties of organic cultivated soils under plastic greenhouse were improved in the results of this study.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.235-244
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf samples of 19 rice cultivars collected from three regions of Korea. Nineteen pink pigmented isolates showing characteristic growth on methanol were obtained. Physiological and biochemical characters of each isolate were examined according to methods described in Bergey's Manual of Systematic Bacteriology. When phylotypes were defined by performing numerical analysis of 37 characteristics, four distinct clusters were formed. The two reference strains, Methylobacterium extorquens AM1 and Methylobacterium fujisawaense KACC10744 were found to group under cluster IV and cluster III respectively. Cluster I diverged on the basis of nitrate reduction and four isolates showed tolerance upto 0.5 M NaCl concentrations. Two strains in cluster I and III were found to possess methane utilizing properties. Most of the isolates in all the four clusters utilized monosaccharides, disaccharide and polyols as carbon source. When the isolates were subjected for indole-3-acetic acid (IAA) analysis in the presence of L-tryptophan, only 8 isolates exhibited IAA production. In addition, the nitrogen source in the medium was found to influence the IAA production. Addition of $(NH_4)_2SO_4$ in the medium led to a 2 to 30 fold increase in the indole synthesis. However, $KNO_3$, $NH_4NO_3$ and $NH_4Cl$ substitution did not significantly stimulate the synthesis of IAA in the growth medium. Result of gnotobiotic root elongation assay significantly increased roots and shoots lengths, and number of lateral roots, which is mediated by IAA production in the culture medium. The rice seedlings primary roots from seeds treated with methylotrophic isolates were on average 27 to 56% longer than the roots from seeds treated with the uninoculated seeds. In addition, application of different high concentrations of authentic IAA ($400g\;mL^{-1}$) to roots of rice seedlings inhibited root growth. However, the IAA concentration from 10 to $200g\;mL^{-1}$, IAA promoted root growth of rice seedlings. These results suggest that bacterial IAA plays a major role in the development of the host plant root system.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.698-703
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• 2001

Background: Endovascular stent-graft insertion in aortic diseases is now generally accepted as an attractive alternative treatment modality. We reviewed our clinical experiences of endovascular stent-graft insertion in thoracic aorta. Material and Method: Since 1995, we performed 8 cases of endovasclar stent-graft insertion. Preoperative diagnoses were aortic aneurysms in 4, traumatic aortic ruptures in 3, and ruptured aortic pseudoaneurysm in 1. All procedures were performed in angiography room with the guidance of fluoroscopy. The stent-graft device is a custom-made 0.35mm thickness Z-shaped stainless steel wires, intertwined with each other using polypropylene suture ligation. It is covered with expanded Dacron vascular graft. Result: All procedures were performed successfully. Follow-up studies revealed 2 minimal perigraft leakages. There was no significant leakage or graft migration. 2 patients expired due to multiple organ failure and fungal sepsis. Other survivors(6) are doing well. Conclusion: Endovascular stent-graft insertion is relatively saft and effective treatment modality in the managment of various types of aortic diseases. In may be an effective alternative in aortic diseases of great surgical risk.

• Journal of Chest Surgery
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• v.42 no.5
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• pp.576-587
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• 2009

Background: The up-regulation of the nitric oxide (NO)-cGMP pathway might be involved in the change of vascular reactivity in rats 3 days after they suffer acute myocardial infarction. However, the underlying mechanism for this has not been clarified. Material and Method: Acute myocardial infarction (AMI) was induced by occluding the left anterior descending coronary artery (LAD) for 30 min (Group AMI), whereas the sham-operated control rats were treated similarly without LAD occlusion (Group SHAM), The concentration-response relationships for phenylephrine (PE), KCl, acetylcholine (Ach) and sodium nitroprusside (SNP) were determined in the endothelium intact E(+) and endothelium denuded E(-) thoracic aortic rings from the rats 3 days after AMI or a SHAM operation. The concentration-response relationships of PE in the E(+) rings from the AMI rats were compared with those relationships in the rings pretreated with nitric oxide synthase (NOS) inhibitor $N{\omega}$-nitro-L-arginine methyl ester (L-NAME) or the cyclooxygenase inhibitor indomethacin. The plasma nitrite/nitrate concentrations were checked via a Griess reaction. The cyclic GMP content in the thoracic aortic rings was measured by radioimmunoassay and the endothelial nitric oxide synthase (eNOS) mRNA expression was assessed by real time PCR. Result: The mean infarct size (%) in the rats with AMI was $21.3{\pm}0.62%$. The heart rate and the systolic and diastolic blood pressure were not significantly changed in the AMI rats. The sensitivity of the contractile response to PE and KCl was significantly decreased in both the E(+) and E(-) aortic rings of the AMI group (p<0.05). L-NAME completely reversed these contractile responses whereas indomethacin did not (p<0.05). Moreover, the sensitivity of the relaxation response to Ach was also significantly decreased in the AMI group (p<0.05). The plasma nitrite and nitrate content (p<0.05), the basal cGMP content (p<0.05) and the eNOS mRNA expression (p=0.056) in the AMI rats were increased as compared with the SHAM group. Conclusion: Our findings indicate that the increased eNOS activity and the up-regulation of the NO-cGMP pathway can be attributed to the decreased contractile or relaxation response in the rat thoracic aorta 3 days after AMI.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.137-143
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• 2000

The present study was performed to investigate the bioconcentration of phosphamidon and profenofos. The BCFs(bioconcentration factors), depuration rate constants and LC$_{50}$ for two pesticides in zebrafish(Brachydanio rerio) were measured by the flow-through system(OECD guideline 305). The results obtained are summarized as follows: The 24-hrs LC$_{50}$, 48-hrs LC$_{50}$, 72-hrs LC.n and 96-hrs LC$_{50}$ were more than 100 mg/l for phosphamidon. The concentration of phosphamidon in zebrafish reached an equilibrium in 12 hrs at low and high concentrations(0.2 mg/l and 1 mg/1). The average BCF values of phosphamidon were less than 1 at low(0.96, n=7) and high concentrations (0.89, n=7) after 12~168 hrs. Depuration rate constants of phosphamidon were 0.18 hr-1 and 0.21 hr-1, half-life of phosphamidon were 3.85 and 3.30 at low and high concentrations(0.2 mg/l and 1 mg/l), respectively, The concentrations of phosphamidon in zebrafish at low and high concentrations were rapidly decreased after 8(0.04 $\mu\textrm{g}$/g) and 12 hrs(0.07 $\mu\textrm{g}$/g). The 24-hrs LC$_{50}$, 48-hrs LC$_{50}$, 72-hrs LC$_{50}$ and 96-hrs LC$_{50}$ were 2.9, 2.6, 2.2 and 2.0 mg/1 for profenofos. The concentration of profenofos in zebrafish reached an equilibrium in 12 hrs at five-hundredth and one-hundredth concentration of 96-hrs LC$_{50}$(0.004 mgA and 0.02 mg/1). The average BCF values of profenofos were 141.9(n=7) and 111.3(n=7) at five-hundredth and one-hundredth concentration of 96-hrs LC$_{50}$(0.004 mg/l and 0.02 mg/1) after 12~168 hrs. Depuration rate constants of profenofos were 0.09 hr$^{-1}$ and 0.10 hr$^{-1}$, half-life of profenofos were 7.70 and 6.93 at five-hundredth and one-hundredth concentration of 96-hrs LC50(0.004 mg/l and 0.02 mg/1), respectively. The concentrations of profenofos in zebrafish at five-hundredth and one-hundredth concentration of 96-hrs LC$_{50}$ decreased agter 8(0.18 $\mu\textrm{g}$/g) and 12 hrs (0.19 $\mu\textrm{g}$/g). The LC$_{50}$ value in zebrafish showed that acute toxicity of profenofos was higher than that of phosphamidon. The BCF values of profenofos were 100 times higher than those of phosphamidon, and depuration rate of phosphamidon was two times faster than that of profenofos.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.1
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• pp.86-94
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• 2004

This study was conducted to mesh selectivity of Beam trawl for shrimps fishing experiment in the coastal waters around Geomundo, South sea of Korea, during from Oct. to Nov. 2002. The selectivity parameters of big head shrimp (Solenocera melantho) have been studied on the covered con-end method. with mesh of 8, 38, 51 and 61 mm. Selection curves and selection parameters were calculated by using a logistic function S=1/(1+exp-(aCL+b)). The mesh selection master curves were estimated by S=1/(1+exp$^{({\alpha}(CL/M)+{\beta}}$), and the optimum mesh size were calculated with (L/M)50 of master curve. Optimum mesh size and selectivity master curves for the southern rough shrimp (Yrachysalambria curvirostris) and smoothshell shrimp (Parapenaeopsis tenella) optimum mesh size and selectivity master curves were estimated by big head shrimp master curves. The results obtained are summarized as follows : Selection parameters '${\alpha}$' and '${\beta}$' of the master curve for big head shrimp were 8.84 and -5.89, and The selection factor of the master curve (L/M)$_{50}$ was 0.67. The optimum mesh size of minimum length for sexual maturity for big head shrimp was 30.7 mm. Estimated (L/M)$_{50}$ for southern rough shrimp and smoothshell shrimp by using the master curve of big head shrimp was 0.73 and the optimum mesh sizes were 25.5 mm for southern rough shrimp and 16.9 mm for smoothshell shrimp, respectively.

• Food Science of Animal Resources
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• v.30 no.5
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• pp.867-871
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• 2010

Objective of this study was to develop a Korean Berkshire line produced using organized management techniques. A total of 448 pigs divided into five line groups were slaughtered and analyzed for their meat quality. $pH_{45}$ values were significantly higher in lines 1~4 (pH 6.08). However, $pH_{24}$ values were lower in line 1 (pH 5.69) and line 3 (pH 5.65) (p<0.05) than in the other lines. Moisture contents were significantly higher in line 5, and the intramuscular fat contents (3.07%) were significantly higher in the other four lines. Water holding capacity (WHC) was higher for line 3 (58.36%) while Warner-Bratzler shear force (WBS) values were significantly higher for line 4 (2.84 kg/$0.5inch^2$) than in the other lines (p<0.05). For meat color properties, L values (CIE L) were 51.59 for line 5, and this value was higher than the other lines. There were no significant differences in $a^*$ values and $b^*$ values among the five lines (p>0.05). Therefore, line 5 was selected as the growth type, whereas line 4 was selected as the Korean Berkshire line that produced pork significantly higher in pH and significantly lower in meat color (lightness), drip loss, and WBS.

• Tuberculosis and Respiratory Diseases
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• v.66 no.2
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• pp.110-115
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• 2009

Background: A forceps-biopsy is performed to acquire tissue from patients with an endobronchial carcinoma using a flexible bronchoscope. Recently, a cryo-biopsy has also been used to acquire tissue samples. Cryo-biopsy is the diagnostic application of extreme cold for the local destruction of abnormal living tissue. This technique is safe, with no radiation danger, no risk of electrical accidents, and a little risk of bleeding. This study compared a forceps-biopsy with a cryo-biopsy using a flexible bronchoscope, and examined the chemosensitivity and level of VEGF (vascular endothelial growth factor) in the specimens obtained from the cryo-biopsy. Methods: We present a prospective study of 30 consecutive patients who underwent a forceps-biopsy between January 2007 and October 2007 with a mean age of 62.1 years and a male:female ratio of 5 : 1. A flexible bronchoscope was inserted to the area of the abnormal lesions, and a cryo-probe was then applied through the working channel of the flexible bronchoscope. A temperature of approximately -h80 was delivered to the tumor site for 8 seconds. The cryo-biopsy was performed after destroying the tumor mass. Results: The mean size of the tissue from the forceps-biopsy and cryo-biopsy were 2.0${\pm}$1.2 mm and 6.0${\pm}$3.0 mm. A chemosensitivity test was performed on 5 specimens obtained using cryo-biopsy and the level of VEGF was examined in 2 specimens obtained from a cryo-biopsy. There were no side effects in either group. Conclusion: Cryo-biopsy using a flexible bronchoscope is a safe and effective technique for acquiring tissue samples.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.492-498
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• 2007

Background: Several lines of evidence suggest that a host's genetic factors influence the outcome of exposure to Mycobacterium tuberculosis. The aim of this study was to determine whether polymorphism in NRAMP1 (natural resistance associated macrophage protein 1) gene is associated with the susceptibility or resistance to tuberculosis infection for patients with drug-sensitive pulmonary tuberculosis (DS-TB) and multi-drug resistant pulmonary tuberculosis (MDR-TB). Methods: Eight genetic polymorphisms of the NRAMP1 gene were investigated in patients suffering with DS-TB (n=100) or MDR-TB (n=102), and in healthy normal controls (NC, n=96). The genetic polymorphisms of NRAMP1 were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The frequency of D543N A/G heterogygotes was significantly higher in the DS-TB subjects than the NCs (OR=2.10, 95% CI: 1.00 to 4.41, p=0.049). The frequency of 823C/T T/C heterozygotes was significantly higher in the DS-TB subjects (OR=2.79, 95% CI: 1.11 to 7.04, p=0.029) and the MDR-TB subject (OR=3.30, 95% CI 1.33 to 8.18, p=0.010) than in the NCs. However, the frequency of these genotypes was not different between the DS-TB and MDR-TB subjects. Conclusion: A significant association was found between NRAMP1 823 C/T polymorphism and pulmonary tuberculosis. This result suggests that NRAMP1 polymorphism may be involved in the development of pulmonary tuberculosis in Koreans.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.479-485
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• 2007

Background: The purpose of this study was to evaluate the differences in CT findings according to sputum smear-positive or -negative results in patients with active pulmonary tuberculosis having a single cavity. Methods: A total of 32 patients with active pulmonary tuberculosis having a single cavity on CT were classified into two groups: smear-positive (n=19) and smear-negative (n=13). The CT findings were reviewed retrospectively. The presence of consolidation, the number of lobes showing consolidation, ground-glass opacity, micronodules and nodule, the maximum diameter of the cavity, and the shape and maximum thickness of the cavity wall were assessed. Result: The maximum diameter of the cavity was $33.84{\pm}13.65mm$ and $27.08{\pm}9.04mm $ in the smear-positive and -negative groups, respectively (p>0.05). The amount of consolidation and the number of lobes with consolidation were found to be 89.5% and 30.8% (p=0.01) and $1.37{\pm}0.90$ and $0.31{\pm}0.48$ (p=0.0002) in the smear-positive and -negative groups, respectively. Consolidations in two or more lobes were only noted in 31.6% of in the sputum smear- positive group (p< 0.05). There were no other significant differences between the two groups. The sensitivity, specificity, positive and negative predictive values for the presence of consolidation were 89.5%, 69.2%, 73.9%, and 81.8%, respectively. Conclusion: While the absence of consolidation on CT may be associated with sputum smear-negative results in patients with active pulmonary tuberculosis having a single cavity, the presence of consolidation in two or more lobes on CT may be associated with spear-positive results in these patients.