• Horticultural Science & Technology
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• v.34 no.6
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• pp.912-923
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• 2016

Watermelon production is often limited by powdery mildew in areas with a large daily temperature range. Development of resistant watermelon cultivars can protect against powdery mildew; however, little is known about the characteristics of its causal agents. Here, we identified the genus and race of a causal pathogen of powdery mildew in Ansung province of South Korea, and developed molecular markers for the generation of resistant watermelon cultivars. The causal pathogen was determined to be Podosphaera xanthii based on multiple sequence alignments of internal transcribed spacers (ITS) of rDNA. The physiological race was identified as 1W, and the Ansung isolate was named P. xanthii 1W-AN. Following inoculation with the identified P. xanthii 1W-AN, we found inheritance of the resistant gene fitting a single dominant Mendelian model in a segregated population ('SBA' ${\times}$ PI 254744). To develop molecular markers linked to fungus-resistant loci, random amplified polymorphic DNA (RAPD) was accomplished between DNA pooled from eight near-isogenic lines (NILs; $BC_4F_6$), originated from PI 254744 and susceptible 'SBB' watermelon. After sequencing bands from RAPD were identified in all eight NILs and PI254744, 42 sequence-characterized amplifiedregion (SCAR) markers were developed. Overall, 107 $F_2$ plants derived from $BC_4F_6$ NIL-1 ${\times}$ 'SBB' were tested, and one SCAR marker was selected. Sequence comparison between the SCAR marker and the reference watermelon genome identified three Nco I restriction enzyme sites harboring a single nucleotide polymorphism, and codominant cleavage-amplified polymorphic site markers were subsequently developed. A CAPS marker was converted to a high-resolution melt (HRM) marker, which can discriminate C/T SNP (254PMR-HRM3). The 254PMR-HRM3 marker was evaluated in 138 $F_{2:3}$ plants of a segregating population ('SBA' ${\times}$ PI254744) and was presumed to be 4.3 cM from the resistance locus. These results could ensure P. xanthii 1W-AN resistance in watermelon germplasm and aid watermelon cultivar development in marker-assist breeding programs.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.5-15
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• 2011

Conventional designs of landfill covers use geosynthetics such as geomembrane and GCL, and clay liners to lower the permeability of final covers of landfill sites. However, differential settlement and the variation of temperature or humidity in landfill sites cause the development of cracks or structural damage inside the final cover. This study examined the application of a Self Recovering Sustainable Liner (SRSL) as an alternative landfill final cover material. SRSL consists of double layers, which have chemicals, can generate precipitates filling the pores of the layers by chemical reaction. The interface material forms an impermeable layer and in case of internal cracks, the reactants of the two layers migrate towards the crack and heal it by forming another liner. In this study the applicability of SRSL material for landfill final cover was examined by performing flexible wall permeameter tests to prove that the hydraulic conductivity is lower than the regulations and unconfined compression tests to judge whether the strength satisfies the restriction for the landfill final cover. Furthermore, the environmental impacts on the permeability and strength were evaluated. The experimental results show that the SRSL has lower hydraulic conductivity and higher strength than the regulations and is little influenced by climatic changes such as wet/dry or freeze/thaw process.

• Journal of Life Science
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• v.25 no.5
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• pp.601-606
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• 2015

Hutchinson (1961) proposed that the large number of species in most plankton communities is remarkable in review of the competitive exclusion principle, which suggests that in homogeneous, well-mixed environments species that compete for the same resources cannot coexist. The principle of competitive exclusion would lead us to conclude that only a few species could coexist in such circumstances. Nevertheless, numerous competing species in most natural habitats are able to coexist, while generally only few resources (niches) limit these communities. It is coined “the paradox of plankton” by Hutchinson. We reviewed some literature of the proposed solutions and give a brief overview of the mechanisms proposed so far. The proposed mechanisms that we discuss mainly include spatial and temporal heterogeneity in physical and biological environment, externally imposed or self-generated spatial segregation, horizontal mesoscale turbulence of ocean characterized by coherent vortices, oscillation and chaos generated by several internal and external causes, stable coexistence and compensatory dynamic under fluctuating temperature in resource competition, and finally the role of toxin-producing phytoplankton in maintaining the coexistence and biodiversity of the overall plankton populations. Especially we sited Roy and Chattopadhyay’s reviews and their toxin-producing hypothesis by phytoplankton. This review may be some information to study plankton communities and effect to put the solutions to the paradox that have been proposed over the years into perspective.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.126-137
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• 2014

Characteristics of heating and drying of Canadian-imported Douglas-fir timber using microwave in order to secure convenience and quality of drying timber and to get basic data for secondary conservation treatment are as follows: As the results of analysis of change curves of internal temperature of the timber after irradiating it, round timber and board timber showed stable heat distribution, heat consumption and surface water-content in heating with 30kW for 30 minutes and 120 minutes and with 40kW for 3 minutes and 9 minutes, respectively. Especially, surface water-content distribution according to heating by microwave showed very even leveling and water-content decrease rate was also more 30% compared to its weight showing excellent dry efficiency. And in case of soaking timbers into liquid chemicals for secondary conservation according to the analysis results of heat consumption, it is expected that large amount of preservative will be permeated. Therefore, timber heated by microwave is remarkably available for using industrial materials and developing secondary utilized products with its fast water-content decrease and dryness and higher heat consumption.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.499-509
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• 2018

This study optimized the bone-softening and fishy odor-reducing process for mackerel Scomber japonicus products using response surface methodology (RSM). The RSM showed that the optimum concentrations of doenjang and citric acid for reducing the fishy odor in bone-softened mackerel were 11.8% and 0.04%, respectively, and the optimum immersion time was 52.2 min. The estimated overall acceptance, salinity, and acidity of the products under these optimum conditions were 7.7 points, 1.1%, and 202.6 mg/100 g, respectively, which were similar to the actual measured values of $7.6{\pm}1.2$ points, $1.0{\pm}0.1%$ and $203.2{\pm}3.8mg/100g$. Moreover, the heating temperature and time for bone-softening based on RSM were $107.3^{\circ}C$ and 4.4 h, respectively. The estimated hardness and proportion of skin removed from the product under the optimal conditions were $161.5g/cm^2$ and 0.09%, respectively, which were also similar to the actual measured values of $171.1{\pm}12.6g/cm^2$ and $0.10{\pm}0.02%$. The optimum bone-softening and fishy odor-reducing process for mackerel consisted of the following steps: thawing (${\leq}10^{\circ}C$, 8 h), filleting, washing/dewatering, immersing in an 11.8% doenjang -0.04% citric acid solution for 52 min, washing/dewatering, heating ($107.3^{\circ}C$, 4.4 h), freezing, depanning, internal and external packaging, and X-ray detection treatment.

• Archives of Pharmacal Research
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• v.26 no.2
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• pp.168-172
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• 2003

Radiation synovectomy is one of the most useful methods for treating patients with refractory synovitis because of its convenience, long-term effects, repeatability and the avoidance of surgery. In this study, we investigated the toxicity, stability and biodistribution of a rhenium-188 ($^{188}$Re)-tin colloid to evaluate its suitability as a synovectomy agent. Twenty four hours after injecting the $^{188}$Re-tin colloids (74 KBq/0.1 mL) into the tail vein of ICR mice, most of the $^{188}$Retin colloidal particles was found in the lungs. In addition, there were no particle size changes at either room temperature or at $37^{\circ}C$ after injecting the $^{188}$Re-tin colloids in human plasma and synovial fluid. In vitro stability tests showed that the $^{188}$Re-tin colloid remained in a colloidal form without a critical size variation over a 2-day period. We investigated the leakage of $^{188}$Retin colloids from the intraarticular injection site with gamma counting in New Zealand white rabbits. The $^{188}$Re-tin colloids (55.5 MBq/0.15 mL) were injected at the cavum articular and the mean retention percentage of the $^{188}$Re-tin colloid was 98.7% for 1 day at the injection site, which suggests that there was neither change in the particle size nor leakage at the injection sites. In the biodistribution study with the SD rats, the liver showed the highest radioactivity (0.0427% ID/organ) except for the injected knees (99.49%). In the SD rats, mild toxicities including the skin or a synovium inflammation were observed as a result of a radioactivity of 15 mCi/kg at the intraarticular injection site. However, there was no systemic toxicity. In the Ovalbumin (OVA)-induced arthritic rabbits, the $^{188}$Re-tin colloid improved the macroscopic, the histological score and reduced the knee joint diameter when compared to the arthritic control. In conclusion, a $^{188}$Re-tin-colloid is considered as a strong candidate for radiation synovectomy with a superior efficacy and safety.

• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.67-78
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• 1987

This study was designed to investigate the effect of board thickness and ring angle on the characteristics including internal check. ring failure, surface check, end check, collapse, thickness shrinkage and width shrinkage of press-drying. The exprimental materials of 6mm-. 9mm- and 12mm-thick board were taken from heartwood and sapwood of oak (Quercus acutissima Carr.) respectively. And boards were numbered according to position in the log(No. 1 to No. 4 for heartwood :md No. 9 for sapwood). Press-drying was at $145^{\circ}C$ platen temperature and 3.5kg/$Cm^2$ platen pressure. The results of this study were summarized as follows. 1. Drying rates for sapwood materials were greater than those for heartwood materials. And drying rates for thinner materials were greater than those for thicker materials. 2. The thinner boards were. the severer surface checking developed in the heartwood materials, and surface checking for heartwood materials had no tendency in board position for the same thickness. Sapwood materials were completely free from surface checking. 3. End checking for heartwood materials had no tendency in board position. The greater deviation of ring angle from perfectly edge-grained was, the severer and checking developed in the sapwood materials. But end checking did not occur in 6mm-thick sapwood materials. 4. The greater deviation of ring angle from perfectly edge-grained was, the severer end checking developed for heartwood and sapwood materials. As board thickness increased, maternal checking developed more severely for heartwood and sapweed materials. 5. For heartwood materials, ring failure, reduced with increasing deviation of ring angle from perfectly edge-grained except 12mm-thick material and showed no significant difference attributable to board thickness. Sapwood materials were completely free from ring failure. 6. For heartwood and sapwood materials, collapse was slight and showed no significant differences attributable to both board thickness and board position. 7. As deviation of ring angle from perfectly edge-grained increased, shrinkage of board thickness decreased for heartwood and sapwood materials. 8. Shrinkage of board width showed no significant differences attributable to both board thickness and board position for heartwood and sapweed materials.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.74-82
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• 1999

Beef, pork and chicken meat that retailed in market were used as experimental samples. Some samples in raw state were packaged with PVDC as aerobic and vacuum condition. The other samples were cooked until internal temperature arrived at $70^{\circ}C$ using electric oven and then packaged immediately in the same way of raw samples. After these samples were irradiated by electron beam (0, 1, 2 kGy), irradiated samples were stored in refrigerator $(2{\sim}4^{\circ}C)$. Identification and quantification of cholesterol oxides were analysed at 0, 7, 14 days. The results were following. The results indicated that raw-vacuum packaged lower detected than that of other treatments. In raw-vacuum packaged, the amounts of $7{\beta}-hydroxycholesterol$ were detected slightly $(below\;0.5\;{\mu}ug/g)$ during storage, and 7-ketocholesterol were detected during every stored time and amounts of this detection were $8.02{\sim}101.30\;{\mu}g/g$. In cooked-aerobic packaged, total amounts of detection were higher than that of other treatments, total amounts of cholesterol oxides were detected about $51.18{\sim}155.90\;{\mu}g/g$ during storage. In all results, pork and chicken samples were similar to the results of beef samples. In all results, total amounts of cholesterol oxides increased significantly as irradiation dose and storage time increased (P<0.05).

• Journal of Wetlands Research
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• v.22 no.4
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• pp.312-320
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• 2020

Various LIDs with natural water circulation function are applied to reduce urban environmental problems and environmental impact of development projects. However, excessive Infiltration and evaporation of LID facilities dry the LID internal soil, thus reducing plant and microbial activity and reducing environmental re duction ability. The purpose of this study was to develop a real-time measurement system with complex sensors to derive the management plan of LID facilities. The test of measurable sensors and Internet of Things (IoT) application was conducted in artificial wetlands shaped in acrylic boxes. The applied sensors were intended to be built at a low cost considering the distributed LID and were based on Arduino and Raspberry Pi, which are relatively inexpensive and commercialized. In addition, the goal was to develop complex sensor measurements to analyze the current state o f LID facilities and the effects of maintenance and abnormal weather conditions. Sensors are required to measure wind direction, wind speed, rainfall, carbon dioxide, Micro-dust, temperature and humidity, acidity, and location information in real time. Data collection devices, storage server programs, and operation programs for PC and mobile devices were developed to collect, transmit and check the results of measured data from applied sensors. The measurements obtained through each sensor are passed through the Wifi module to the management server and stored on the database server in real time. Analysis of the four-month measurement result values conducted in this study confirmed the stability and applicability of ICT technology application to LID facilities. Real-time measured values are found to be able to utilize big data to evaluate the functions of LID facilities and derive maintenance measures.

• Journal of Yeungnam Medical Science
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• v.7 no.2
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• pp.197-202
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• 1990

Mechanical obstruction of the common hepatic duct includes the following causes ; choledocholithiasis, sclerosis, cholangitis, pancreatic carcinoma, cholangiocarcinoma, postoperative stricture, primary hepatic duct carcinoma, enlarged cystic duct lymph nodes, and metastatic nodal involvement of the porta hepatis. Partial mechanical obstruction of the common hepatic duct caused by impaction of stones and inflammation surrounding the vicinity of the neck of the gallbladder had been reported on the "syndrome del conducto hepatico" in 1948 by Mirizzi. Nowadays, this disease was named by Mirizzi syndrome. Mirizzi syndrome is a rare entity of common hepatic duct obstruction that results from an inflammatory response secondary to a gallstone impacted in the cystic duct or neck of the gallbladder. It results from an almost parallel course and low insertion of the cystic duct into the common hepatic duct. In a varient of Mirizzi's syndrome, the cause of the common hepatic duct obstruction was a primary cystic duct carcinoma rather than gallstone disease. A 71-year-old man was admitted with a four-day history of right upper quadrant abdominal pain. Past medical history was unremarkable. On physical examination, the patient had a temperature of $38^{\circ}C$, icteric sclera and right upper quadrant tenderness. Pertinent laboratory findings included WBC 18,000/$cm^2$;albumin 2.6g/dl(normal 3.9-5.1) ; SGOT 183u/L(normal 0-50) ; SGPT167u/L(normal 0-65) ; bilirubin, 8.2mg/dl(normal 0-1) with the direct bilirubin, 4.4mg/dl(normal 0-0.4). Ultrasonography revealed a dilated extrahepatic biliary tree. ERCP showed that the superior margin was angular and more consistent with a calculus causing partial CHD obstruction(Mirizzi syndrome). At surgery a diseased gallbladder containing calculi was found. In addition, there was two calculi partially eroding through the proximal portion of the cystic duct and compressing the common hepatic duct. A cholecystectomy and excision of common bile duct was performed, with Roux-en-Y hepaticojejunostomy. The postoperative course was uneventful.