• Journal of Veterinary Science
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• v.21 no.4
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• pp.65.1-65.13
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• 2020

Background: Aleutian mink disease virus (AMDV) causes major economic losses in fur-bearing animal production. The control of most AMDV outbreaks is complex due to the difficulties of establishing the source of infection based only on the available on-farm epidemiological data. In this sense, phylogenetic analysis of the strains present in a farm may help elucidate the origin of the infection and improve the control and biosecurity measures. Objectives: This study had the following aims: characterize the AMDV strains from most outbreaks produced at Spanish farms between 2012-2019 at the molecular level, and assess the utility of the combined use of molecular and epidemiological data to track the possible routes of infection. Methods: Thirty-seven strains from 17 farms were partially sequenced for the NS1 and VP2 genes and analyzed phylogenetically with other strains described worldwide. Results: Spanish AMDV strains are clustered in four major clades that generally show a good geographical correlation, confirming that most had been established in Spain a long time ago. The combined study of phylogenetic results and epidemiological information of each farm suggests that most of the AMDV outbreaks since 2012 had been produced by within-farm reservoirs, while a few of them may have been due to the introduction of the virus through international trade. Conclusions: The combination of phylogenetic inference, together with epidemiological data, helps assess the possible origin of AMDV infections in mink farms and improving the control and prevention of this disease.

• Korean journal of applied entomology
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• v.16 no.3 s.32
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• pp.171-179
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• 1977

Since the outbreak of the brown planthopper (Nilaparvata lugens) in 1915 caused tremendous losses in rice production, one of the more effective method of prevention of such a disaster could be the establishment of longterm forecasting system, In 1916 the author indicated there was a correlation between sunspot activities and brown planthopper and the white back planthopper outbreaks. However, the examples seem to be too small size to state a definite correlation. The purpose of the present study IS to revi~w the history of the brown planthopper outbreaks, and to establish a more effective forcasting system. The present forcasting methods are based on light trap catches of adults which already migrate into this country from mainland China. The regular cycle of 11.2 years of sunspot activity began in 1710, and was continued to present. To gather more records of brown planthopper, the author checked 'Joseon Wangjo Silrok' and analized the so-called 'Hwang' 'Hwang-chung' and 'Chung' which have multiple meanings, together with 'Samguk Sagi' 'Goryo Sa' and 'Munheon Bigo.' The results obtained by the about from review of these old literature citations revealed that ten species of insect and unknown species were involved: i. e., pine moth (Dendrolimus spectabilis), army worm (Mythimna separata), brown planthopper (Nilarvata lugens), white-back planthopper (Sogatella furcifera), migratory locust (Locutsa migratoria), rice stem borer (Chilo suppressalis,), mole cricket (Gryllotalpa africana), rice-plant weevil (Echinocnemus squameus), cut worm (Euxoa segetum), and mulberry pyralid Margaronia pyloalis) The suspected incidence of planthopper in old records expressed by 'Hwang' or 'Chung' revealed a total or 25 out of 37 in 'Samguk sagi,' 21 out of 49 in 'Goryo sa,' 9 of 73 in 'Wanjo-silrog,' and none of 8 in 'Munheon bigo' were planthoppers. Therefore, a total of 36 out of 167 records of insect incidence in the old literature can be possibly attributed to planthoppers. The brown planthopper and white-back planthopper migrate together to Korea every year from mainland China, However, the number of each species are differ by year. In 1975 outbreak the brown planthopper was dominant; and the white-back planthopper prevailed in 1946 and 1977 outbreaks, During the course of this study, the author was able to add a new record of outbreak of planthop per. In 1916 the white-back planthopper outbreak caused serious losses in Chungcheong-namdo and Jeonla-namdo, with losses estimated as high as 160 and 190 thousand seok (23.2 and 27.5 thousand M/T), in Naju and Secheon county, respectively. Since 1912, major outbreaks of brown planthopper or white-back planthopper have been recored 5 times. These occurrences coincide and well matched the period of minimum number of sunspots, With these authenticated records of planthoppers, the author believes there is a close correlation between brown planthopper and white-back planthopper outbreaks in Korea and sunspot activities. Therefore, in years of low number of sunspots, we should watch for and expect outbreaks of these. insects. At this time, it will be necessary to provide all possible prevention measures.

• ALGAE
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• v.32 no.2
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• pp.101-130
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• 2017

The ichthyotoxic Cochlodinium polykrikoides red tides have caused great economic losses in the aquaculture industry in the waters of Korea and other countries. Predicting outbreak of C. polykrikoides red tides 1-2 weeks in advance is a critical step in minimizing losses. In the South Sea of Korea, large C. polykrikoides red tide patches have often been recorded offshore and transported to nearshore waters. To explore the processes of offshore C. polykrikoides red tides, temporal variations in 3-dimensional (3-D) distributions of red tide organisms and environmental parameters were investigated by analyzing 4,432 water samples collected from 2-5 depths of 60 stations in the South Sea, Korea 16 times from May to Nov, 2014. In the study area, the vegetative cells of C. polykrikoides were found as early as May 7, but C. polykrikoides red tide patches were observed from Aug 21 until Oct 9. Cochlodinium red tides occurred in both inner and outer stations. Prior to the occurrence of large C. polykrikoides red tides, the phototrophic dinoflagellates Prorocentrum donghaiense (Jun 12 to Jul 11), Ceratium furca (Jul 11 to Aug 21), and Alexandrium fraterculus (Aug 21) formed red tides in sequence, and diatom red tides formed 2-3 times without a certain distinct pattern. The temperature for the optimal growth of these four red tide dinoflagellates is known to be similar. Thus, the sequence of the maximum growth rates of P. donghaiense > C. furca > A. fraterculus > C. polykrikoides may be partially responsible for this sequence of red tides in the inner stations following high nutrients input in the surface waters because of heavy rains. Furthermore, Cochlodinium red tides formed and persisted at the outer stations when $NO_3$ concentrations of the surface waters were < $2{\mu}M$ and thermocline depths were >20 m with the retreat of deep cold waters, and the abundance of the competing red-tide species was relatively low. The sequence of the maximum swimming speeds and thus potential reachable depths of C. polykrikoides > A. fraterculus > C. furca > P. donghaiense may be responsible for the large C. polykrikoides red tides after the small blooms of the other dinoflagellates. Thus, C. polykrikoides is likely to outgrow over the competitors at the outer stations by descending to depths >20 m and taking nutrients up from deep cold waters. Thus, to predict the process of Cochlodinium red tides in the study area, temporal variations in 3-D distributions of red tide organisms and environmental parameters showing major nutrient sources, formation and depth of thermoclines, intrusion and retreat of deep cold waters, and the abundance of competing red tide species should be well understood.

• Journal of Aquaculture
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• v.18 no.2
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• pp.122-129
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• 2005

Ammonia is the major limiting factor in intensive aquaculture production systems. Therefore, quantification of ammonia excretion is important for the water quality management in aquaculture systems. Ammonia excretion is known to be affected by many factors such as body weight and dietary protein level (DPL). In this study, experiments were carried out to investigate the effects of body weight and DPLs on the rates of ammonia excretion of Nile tilapia Oreochromis niloticus. Three sizes of fishes (mean initial weight; 4.8 g,42.7 g and 176.8 g) were fed each of two dietary protein levels (30.5% and 35.5%). Daily feeding levels for the three fish sizes of 4.8 g, 42.7 g and 176.8 g were 6%, 3%, and 1.5% body weight per day, respectively. Each group of fish was stocked in a 17.1-L aquarium and all treatments were triplicated. Following feeding, the weight-specific ammonia excretion rate of O. niloticus increased, peaked at 4 to 8 h, and returned to pre-feeding levels within 24 h. Total ammonia nitrogen (TAN) excretion.ate per unit weight decreased with the increase of fish weight for each diet (P<0.05). The TAN excretion rate increased with increasing dietary protein content for each fish size (P<0.05). TAN excretion rates (Y) for each diet with different fish weights were described by the following equations: low DPL diet (30.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=955.69-147.12\;lnX\;(r^2=0.95)$, high DPL diet (35.5%): $Y\;(mg\;kg^{-1}\;d^{-1})=1362.41-209.79\;lnX\;(r^2=0.99)$. Where: X=body weight (g wet wt.). The TAN excretion rates ranged 28.5%-37.1% of the total nitrogen ingested for the low DPL diet (30.5%) and 37.4-38.5% for the high DPL diet (35.5%). Total nitrogen losses of fish fed the high DPL diet $(35.5%;\;0.26\sim0.91g\;kg^{-1}\;d^{-1})$ were higher than those fed the low DPL diet $(30.5%;\;0.22\sim0.68g\;kg^{-1}\;d^{-1})$. The losses decreased per kg of fish as fish size increased. Results will provide valuable information fer water quality management and culture of Nile tilapia in recirculating aquaculture systems.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.555-564
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• 2010

Aphid and mite are the major insects that harm corn. These insects are difficult to control because they are very sensitive to environmental conditions. The purpose of this experiment was to information the loss in quantity of corn and to select inbred lines with resistance after exposing corn to aphid and mite. When exposed to aphid, the average loss in grain yield, ear length, ear diameter, 100 kernel weight, kernel length, kernel width, and kernel thickness were 18.4, 10.9, 1.7, 5.4, 2.3, 1.5 and -0.2%, respectively. When exposed to mite, the average loss in grain yield, ear length, ear diameter, 100 kernel weight, kernel length, kernel width, and kernel thickness were 49.7, 16.5, 20.7, 18.9, 9.5, and -3.4, respectively. Mite had more significant impact on the loss than aphid. Among these factors, grain yield and ear dimater were most significantly correlated on the loss to aphid ($r=0.83^{**}$), while kernel length and thickness were most significantly correlated on the loss to mite ($r=0.83^{**}$). However, ear length was not related to loss to the two insects. The inbred lines that were often used for $F_1$ hybrid which was lower than the average loss by aphid, were KS7, B68, 61B3, 70A1, and KS5, while the inbred lines that were often used for $F_1$ hybrid which was lower than the average decrease by mite, were KS7, B68, 61B3, 66B2-4, 70A1, 72B2, and KS5. These inbred lines could be used to breed inbred lines, hybrid, and open pollination variety that confer resistant to aphid and mite.

• BMB Reports
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• v.40 no.5
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• pp.773-782
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• 2007

Different isolates of the soil bacterium Bacillus thuringiensis produce multiple crystal (Cry) proteins toxic to a variety of insects, nematodes and protozoans. These insecticidal Cry toxins are known to be active against specific insect orders, being harmless to mammals, birds, amphibians, and reptiles. Due to these characteristics, genes encoding several Cry toxins have been engineered in order to be expressed by a variety of crop plants to control insectpests. The cotton boll weevil, Anthonomus grandis, and the fall armyworm, Spodoptera frugiperda, are the major economically devastating pests of cotton crop in Brazil, causing severe losses, mainly due to their endophytic habit, which results in damages to the cotton boll and floral bud structures. A cry1Ia-type gene, designated cry1Ia12, was isolated and cloned from the Bt S811 strain. Nucleotide sequencing of the cry1Ia12 gene revealed an open reading frame of 2160 bp, encoding a protein of 719 amino acid residues in length, with a predicted molecular mass of 81 kDa. The amino acid sequence of Cry1Ia12 is 99% identical to the known Cry1Ia proteins and differs from them only in one or two amino acid residues positioned along the three domains involved in the insecticidal activity of the toxin. The recombinant Cry1Ia12 protein, corresponding to the cry1Ia12 gene expressed in Escherichia coli cells, showed moderate toxicity towards first instar larvae of both cotton boll weevil and fall armyworm. The highest concentration of the recombinant Cry1Ia12 tested to achieve the maximum toxicities against cotton boll weevil larvae and fall armyworm larvae were 230 ${\mu}g/mL$ and 5 ${\mu}g/mL$, respectively. The herein demonstrated insecticidal activity of the recombinant Cry1Ia12 toxin against cotton boll weevil and fall armyworm larvae opens promising perspectives for the genetic engineering of cotton crop resistant to both these devastating pests in Brazil.

• Fashion & Textile Research Journal
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• v.16 no.6
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• pp.945-953
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• 2014

This study aims to develop protective pants to relieve impact from falls and to present basic data for the development. The survey results are as follows; First, 45% of the respondents were in their 60s and 55% of them were in their over 70s and older. Also, 64% of them have fallen once for the past year and 36% of them have fallen twice or more. The older they were, the more there were those who have fallen twice or more. This indicated the older people has experienced more fall accidents again after a initial fall accident. Second, as per accident situations, the survey showed that fall accidents happened the most in the winter and in the afternoon (12-18 pm). Also, it happened on a street mostly and they were wearing sneakers or hiking boots when they got a hurt slipped in a front or side by missing their step in a walk. The injury areas are mostly knee and ankle. They had the bruises or a sprain in their knee and ankle mostly. The rate of bone fracture was 19.5%. Therefore, the protection area to falls in lower body is the knee. But hip and hip joint should be protected with knee as well because those are usually be broken when it is damaged. Third, approximately 80% of those who were hospitalized for treatment had surgery. Patients who had surgery were rather in their over 70s than in their 60s. The older they were, the more serious their fracture was. The period of hospital or outpatient treatment is more than three weeks in many cases. They responded their health got worse after falls. Aftereffects of accidents were physical discomfort, anxiety and medical costs. Falls to the old makes physical damage, psychological damage, which cause reduced physical activity and the increased cost of health care with economic losses. So it results on a negative impact on the life of the old. Fourth, elderly females were rarely aware of impact protective clothing and they have never purchased such clothing. For impact protective pants, the major consideration was suitable design for their body types. They liked casual style with front or side pockets and simple designs without any patterns or decorations. As per pants materials, they responded that they need functionality, activity and elasticity. Among the functional points, insulation of cloths are considered importantly, so the heat reservance of material in the impact protective pants should be considered carefully.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.134-134
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• 2010

Fuel cell is a device that directly converts chemical energy in the form of a fuel into electrical energy by way of an electrochemical reaction. In the anode for a high temperature fuel cell, nickel or nickel alloy has been used in consideration of the cost, oxidation catalystic ability of hydrogen which is used as fuel, electron conductivity, and high temperature stability in reducing atmosphere. Most MCFC stacks currently operate at an average temperature of $650^{\circ}C$. There is some gains with decreased temperature in MCFC to diminish the electrolyte loss from evaporation and the material corrosion, which could improve the MCFC life. However, operating temperature has a strong related on a number of electrode reaction rates and ohmic losses. Baker et al. reported the effect of temperature (575 to $650^{\circ}C$). The rates of cell voltage loss were 1.4mV/$^{\circ}C$ for a reduction in temperature from 650 to $600^{\circ}C$, and 2.16mV/$^{\circ}C$ for a decrease from 600 to $575^{\circ}C$. The two major contributors responsible for the change in cell voltage with reducing operation temperature are the ohmic polarization and electrode polarization. It appears that in the temperature range of 550 to $650^{\circ}C$, about 1/3 of the total change in cell voltage with decreasing temperature is due to an increase in ohmic polarization, and the electrode polarization at the anode and cathode. In addition, the oxidation reaction of hydrogen on an ordinary nickel alloy anode in MCFC is generally considered to take place in the three phase zone, but anyway the area contributing to this reaction is limited. Therefore, in order to maintain a high performance of the fuel cell, it is necessary to keep this reaction responsible area as wide as possible, that is, it is needed to keep the porosity and specific surface area of the anode at a high level. In this study effective anodes are prepared for low temperature MCFC capable of enhancing the cell performance by using zirconium hydride at least in part of anode material.

• Journal of Mushroom
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• v.14 no.3
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• pp.100-104
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• 2016

Mushroom flies are one of the most serious threats to mushroom production and cultivation in Korea, and they cause significant losses in yield and quality. In this study, we investigated the occurrence and control of mushroom flies in farms where Agaricus bisporus was cultivated in Chungnam. The cultivation period was more than 7 years in the 32 mushroom farms examined; about 28% were environment-friendly cultivation farms, and 72% were conventional cultivation farms. Mushroom flies were a major pest in about 84% of the examined farms. Most of the mushroom flies were sciarids and phorids (71% and 24%, respectively). The adult flies were found throughout the year, but their occurrence was the highest in September when the temperature increased. In general, the occurrence of mushroom flies in the examined farms was high; however, insect nets and post-crop steaming programs used as basic control methods were not implemented properly. Our findings show that integrated pest management of mushroom flies is urgently required for A. bisporus cultivation in Korea.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.141-154
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• 2015

In general, conventional criticality analysis for spent fuel transport/storage systems have been performed based on the assumption of fresh fuel concerning the potential uncertainties from number density calculations of actinide nuclides and fission products in spent fuel. However, these evaluation methods cause financial losses due to an excessive criticality margin. In order to overcome this disadvantage, many studies have recently been conducted to design and commercialize a transportation and storage cask applied to the Burnup Credit (BUC). This study conducted an assessment to ensure criticality safety for reactor operating parameters, axial burn-up profiles and misload accident conditions, which are the factors that are likely to affect criticality safety when the BUC is applied to the dual-purpose cask under development at the KOrea RADioactive waste agency (KORAD). As a result, it was found that criticality resulting from specific power, changed substantially and relied on conditions of low enrichment and high burn-up. Considering the end effect in the case of high burn-up produced a positive-definite result. In particular, the increment of maximum effective multiplication factors due to misloading was 0.18467, confirming that misload is a factor that must be taken into account when applying the BUC. The results of this study may therefore be utilized as references in developing technologies to apply the BUC to domestic models and operational procedures or preventing any misload accidents during the process of spent fuel loading.