• The Korean Journal of Mycology
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• v.18 no.2
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• pp.96-101
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• 1990

This study was conducted to select the promising antifungal microoganisms for biological control of wet bubble, Mycogone perniciosa. Ninty one isolates of fungi, 342 isolates of bacteria, and 556 actinomycetes were isolated from mushroom composts and soils, were subjected to primary screening test on agar medium base for their antimicrobial spectra. Among them, 12 bacteria and 71 actinomycetes were selected. Among the antibiotic producing microoganisms, 5 cultures were selected on the basis their antibiotic activities on casing soil with Benlate nontolerence M. perniciosa. Finally, AJ-117, AJ-136 and AK-139 were selected as microoganism with antifungal activity against two strains of M. perniciosa.

• Korean Journal of Materials Research
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• v.21 no.1
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• pp.39-45
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• 2011

In this study, the heat flow of the plant scale aluminum extrusion process was investigated to establish optimum continuous heat treatment conditions. During the extrusion of 6061 aluminum alloy, processing parameters such as the extrusion pressure, speed and temperature histories of billets were logged as a function of time. The surface temperature of the billets increased at constant ram speed, while it decreased with decreases of the ram speed. In order to maintain the billet temperature within a solutionizing temperature range prior to the succeeding water quenching step, the ram speed or the temperature of the blower should be controlled. The temperature histories of the billets during the extrusion and hot air blowing processes were successfully simulated by using the velocity boundary model in ANSYS CFX. The methodology to design an optimum process by using a commercial simulation program is described in this study on the basis of the metallurgical validation results of the microstructural observation of the extrudates. The developed model allowed the advantages of taking into account the motion of the extrudate coupled with the temperature change based on empirical data. Calculations were made for the extrudate passing through the isothermal chamber maintained at appropriate temperature. It was confirmed that the continuous heat treatment system is beneficial to the productivity enhancement of the commercial aluminum extrusion industry.

• Journal of Wetlands Research
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• v.18 no.1
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• pp.84-93
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• 2016

As a transition region between ocean and land, coastal wetlands are significant ecosystems that maintain water quality, provide natural habitat for a variety of species, and slow down erosion. The energy of coastal waves and storm surges are reduced by vegetation cover, which also helps to maintain wetlands through increased sediment deposition. Wave attenuation by vegetation is a highly dynamic process and its quantification is important for understanding shore protection and modeling coastal hydrodynamics. In this study, laboratory experiments were used to quantify wave attenuation as a function of vegetation type as well as wave conditions. Wave attenuation characteristics were investigated under regular waves for rigid model vegetation. Laboratory hydraulic test and numerical analysis were conducted to investigate regular wave attenuation through emergent vegetation with wave steepness ak and relative water depth kh. The normalized wave attenuation was analyzed to the decay equation of Dalrymple et al.(1984) to determine the vegetation transmission coefficients, damping factor and drag coefficients. It was found that drag coefficient was better correlated to Keulegan-Carpenter number than Reynolds number and that the damping increased as wave steepness increased.

• The Journal of the Korean Society for Microbiology
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• v.21 no.1
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• pp.17-31
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• 1986

Forty clinical isolates of Serratia marcescens were tested for their susceptibility to 19 antimicrobial drugs and studied on the molecular characteristics of R plasmids. Cefotaxime (Ct) was the most effective drug and only 2 (5%) strains were resistant to this drug. Thirteen to 18% of strains were resistant to cefoperazone (Cz), amikacin (Ak). and trimethoprim (Tp), and 28 to 40% were resistant to piperacillin (Pi), nalidixic acid (Na), gentamicin (Gm), and cefoxitin (Cx). A majority of strains were resistant to carbenicillin (Cb), tobramycin (Tp), kanamycin (Km), and cefamandole (Cd), and all to cephalothin. One half of the isolates were resistant to 10 or more drugs. $MIC_{90}$ of Pi to Gm-resistant strains (Gm') were 8 times higher than that to Gm-susceptible strains (Gm'), but $MIC_{90}$ of Ak, Cx, Ct, and Cz were almost the same between both Gm' and Gm' strains. Nine (23.7%) strains among 38 of multiply drug-resistant S. marcescens transferred conjugally their partial patterns of resistance to E. coli or Klebsiella strains, and two S. marcescens strains producing bacteriocin transferred their resistance to Klebsiella only, but not to E. coli. The plasmid profiles of S. marcescens were studied by the methods of SDS lysis and agarose gel electrophoresis. Twenty-four (60%) strains carried one to four plasmids of 1.4. to 144 Mdal, and conjugative R plasmids of 49 to 127 Mdal were noted in transconjugants. MIC levels of drugs in transconjugants were variable by the R plasmids and recipient strains.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.170-175
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• 2023

In this study, the effect of MnSO₄ on the insecticidal crystal (IC) produced by Bacillus thuringiensis for a rapid detection medium was analyzed. The strains used included one B. thuringiensis reference (KCTC 1511) and nine wild-type strains. The IC in B. thuringiensis was detected following the method published by the Ministry of Food and Drug Safety in Korea. In the nutrient agar to which 0.005% MnSO₄ was added, IC was observed on two of the three plates after 48 hours of incubation and on all three plates after 120 hours. In AK agar, IC was observed on one and two of the three plates after 48 and 96 hours of incubation, respectively. These results indicated that 0.005% MnSO₄ nutrient agar is more appropriate than AK agar for production of IC in B. thuringiensis. The effect of various MnSO₄ concentrations on IC production was studied after 24 hours of incubation. IC was produced on 1 of the 10 plates with 0.000% MnSO₄ nutrient agar, 2 of the 10 plates with 0.001% MnSO₄ nutrient agar, and 3 of the 10 plates with 0.002% MnSO₄ nutrient agar. IC was not observed for the other nutrient agars containing 0.003%-0.009% MnSO₄. These results indicated that nutrient agar with 0.002% MnSO₄ led to the most rapid production of IC by B. thuringiensis after 24 hours of incubation. However, the conditions for IC production by B. thuringiensis depended on the incubation conditions and strain activity. Therefore, further studies are needed to verify the effects of 0.002% MnSO₄ on the production of IC by various Bacillus thuringiensis strains.

• Journal of Chest Surgery
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• v.50 no.5
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• pp.371-377
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• 2017

Background: Lesions in distal target arteries hinder surgical bypass procedures in patients with peripheral arterial occlusive disease. Methods: Between April 2012 and October 2015, 16 patients (18 limbs) with lifestyle-limiting claudication (n=12) or chronic critical limb ischemia (n=6) underwent femoral-above-knee (AK) polytetrafluoroethylene (PTFE) bypass grafts with a bridging stent graft placement between the distal target popliteal artery and the PTFE graft. Ring-supported PTFE grafts were used in all patients with no available vein for graft material. Follow-up evaluations assessed clinical symptoms, the ankle-brachial index, ultrasonographic imaging and/or computed tomography angiography, the primary patency rate, and complications. Results: All procedures were successful. The mean follow-up was 12.6 months (range, 11 to 14 months), and there were no major complications. The median baseline ankle-brachial index of 0.4 (range, 0.2 to 0.55) significantly increased to 0.8 (range, 0.5 to 1.0) at 12 months (p<0.01). The primary patency rate at 12 months was 83.3%. The presenting symptoms resolved within 2 weeks. Conclusion: In AK bypasses with a diffusely diseased distal target popliteal artery or when below-knee (BK) bypass surgery is impossible, this procedure could be clinically effective and safe when used as an alternative to femoral-BK bypass surgery.

• CELLMED
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• v.6 no.4
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• pp.26.1-26.3
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• 2016

The purpose of this article is to argue that Korean music, Yukjabaegi (six-bit songs), helps us overcome grief. It is not untrue to say that Yukjabaegi is among the greatest types of music in Korea. This is a testament to the prominence of this statue among Han Ak (Korean music, 韓樂). Empathy is an inherent human quality involving all parts of the brain which is also linked to feelings of love. Empathy is created the moment we imagine ourselves in someone else's situation. Moreover, if empathy is good for us, the generation of empathy may actually mobilize our strength. Koreans have superior strength in overcoming grief and difficult situations by singing together. Often Koreans feel that their lives and labors are difficult, they start singing Yukjabaegi because they consider grief and anxiety wear on a person more than hard work. Listening to and singing Yukjabaegi can cheer up people who feel as limp as a rag after hard labor. Tackling reality and venting the experience via creative expression is bound to be healthy. Under a change of the rhythm pattern, Yukjabaegi thus becomes a major form of amusement for those suffering from difficult situations and comes as a true friend to share in our grief with us. Singing together via Yukjabaegi is a time to share grief. Thus, this, author believes that it is related to empathy. It helps us overcome grief by means of music therapy.

• Mycobiology
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• v.28 no.1
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• pp.27-32
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• 2000

The ectomycorrhizal roots were collected from the soils around the bases of basidiocarps of the four edible mushrooms in the stands of Pinus densiflora or Querus acutissima communities (Mt. Wol-Ak in Eastern Chung-Puk): The basidiocarps of Tricholoma matsutake (TM), Sarcodon asparatus (SA), S. imbricatum (SI), and Polyozellus multiplex (PM) are usually collected. The ectomycorrhizal roots of TM, PM and SI were related to the roots of P. densiflora, but the other to the roots of Q. acutissima in Korea. Particularly, the basidiocarps of PM were collected in the mixed stand of both P. densiflora and Q. acutissima. The morphologies of the ectomycorrhizal roots were observed to be the yellowish brown coral (dichromatous) or pyramid types in the roots of the pine, but dark brown un-branched sticks (roots) in the ends of ectomycorrhizal roots of Querus plants. The un-branched roots were covered with the dark mycelia (rhizomorph) around them. Therefore, the ectomyorrhizal roots of PM were observed to have two kinds of types; The single blackish un-branched roots were observed to be attached to the yellowish coral type roots. The bundles of TM mycelia were filled with cortical cells (in the roots of P. densiflora), but the mycelia of the other fungi (Aphylloporales) were massed between the cortical cells of P. densiflora or Q. acutissima. Their anatomical and gross features were considered to be simailar but very important in the ectomycorrhizal roots for these edible mushrooms.

• Journal of Plant Biology
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• v.11 no.4
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• pp.1-8
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• 1968

The persent paper discusses the relation between water pollution and aquatic organisms resulted from the study of the water quality and the kinds of algea and aquatic insects both of the An-yang River from Mt. Kwan-ak to the Han River and of the Kock-neung River from Mt. Puk-han to the Han River during the spring of 1965 and 1966. According to the change of water quality, the An-yang River might be divided into three areas. In the first area, from Mt. Kwan-ak to near An-yang town, water quality is not so polluted that may aquatic organisms such as Anisogamarus ryotoensis, Epeorus, Cambaroides, Zygnem, Batrachospermum moniliform, Draparnaldia glomerata are found. In the second area where water is polluted by the inflow of sewerage water from An-yang town, the concentration of chloride, COD, ammonia-N, nitrate-N, alkali degree increased. Therefore, few aquatic insects and algea are found. In the third area, it is much polluted by the industrial sewerage water frojm Yeong-dong-po; and so the aquatic organisms that indicate strong pollution such as Oscillatoria, Euglena, Tubifex are found in this area. It is also significant that the Nereis japonica that indicates the pollution of brackish water is discorved in the some area. In the case of the Kock-neung River, however, it is not clearly divided into areas, as in the case of the An-yang Riber, according to the pollution of water; but because of villages and towns along the river the gradual pollution of water; but because of villages and towns along the river the gradual pollution of water is observed and accordingly, a considerable change in aquatic organisms is also found in this river. In the area near II-yeung town, for instance, the concentration of the chloride, hardness, nitrite, nitrate is very low, and ammonia-N is not detected; and accordingly the aquatic insects that generally inhabit in mountain stream, such as Anisogamarus ryotoensis, Cambaroides, Epeorus, Thraubs, Hydropsyche are found here. In the down stream of the river, from Kock-chon, the quality of water is considerably polluted and fine sands are found laid on the bottom of the stream; therefore, the aquatic insects are very few, but the algea such as Navicula, Pleusigma, Oscillatoria that indicate water pollution are found in this area.

• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.575-598
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• 2017

This paper introduces and studies a generalization of the classical Struve function of order p given by $$_aS_{p,c}(x):=\sum\limits_{k=0}^{\infty}\frac{(-c)^k}{{\Gamma}(ak+p+\frac{3}{2}){\Gamma}(k+\frac{3}{2})}(\frac{x}{2})^{2k+p+1}$$. Representation formulae are derived for $_aS_{p,c}$. Further the function $_aS_{p,c}$ is shown to be a solution of an (a + 1)-order differential equation. Monotonicity and log-convexity properties for the generalized Struve function $_aS_{p,c}$ are investigated, particulary for the case c = -1. As a consequence, $Tur{\acute{a}}n$-type inequalities are established. For a = 2 and c = -1, dominant and subordinant functions are obtained for the Struve function $_2S_{p,-1}$.