• Pediatric Infection and Vaccine
• /
• v.13 no.1
• /
• pp.71-77
• /
• 2006

Purpose : Shigellosis is still an important cause of acute food-borne diarrheal diseases throughout the world. We investigated the transmission routes and clinical course through the outbreak of shigellosis in Mapo-Gu, Seoul. Methods : From October 7th to November 19th in 2005, Mapo-Gu public health center had referred 32 patients with confirmed or suspected shigellosis to the National Medical Center. We had investigated source of infection, epidemiology, laboratory findings, and clinical course of the cases occurred during this outbreak. Results : Among 32 patients, 24 patients had been confirmed with shigellosis, 8 patients had been diagnosed with suspected shigellosis. They ranged in age from 5 months to 12 years old and their mean age was 6.5 years. The clinical manifestations were as follows; diarrhea, fever, abdominal pain and asymptomatic condition. Symptoms had sustained for 3.7 days on the average. S. sonnei were cultured by rectal swab and founded to be resistant to ampicillin and TMP/SMX except to 3rd generation cephalosporin. After treatment with antibiotics such as cefixime and ceftriaxone or imipenem and conservative treatment with electrolyte and fluid replacement for 5~7 days, Stool cultures of the rectal swab grew no Shigella in these cases except 3 cases. Conclusion : An outbreak of shigellosis had occurred in a preschool and elementary school children. From the same results of antimicrobial susceptibility and pulsed-field gel electrophoresis patterns in this study, we suggest that the outbreak of shigellosis in this report had been originated from a single strain. According to all negative results about suspected food and water cultures, we couldn't find out source of infection. Through materials offerred by Mapo-Gu Public Health Center, we presumed the trasmission routes probably were person-to-person.

• Asian-Australasian Journal of Animal Sciences
• /
• v.13 no.4
• /
• pp.464-469
• /
• 2000

Experiments were conducted to determine the effects of soybean meal (SBM) as a source of protein and sago meal (SM) as a source of carbohydrate on in situ and in vivo digestibility of dietary components in four male goats (Kambing Katjang) and four male sheep (Malin) weighing 25-35 kg. Rumen volume, as well as rumen fluid dilution rate were also determined. The animals were housed in single pens with individual feeding and drinking troughs and each animal was fitted with a rumen fistula. They were fed two diets : chopped rice straw+200 g soybean meal (SBM), and chopped rice straw+190 g soybean meal+300 g sago meal (SBM+SM). Rice straw was offered ad libitum. The supplements were isonitrogenous (80 g crude protein/animal/d), but the proportions of dry matter (DM), organic matter (OM), crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) were lower in the SBM supplement (191, 165, 11, 40, 15 g/animal/d for DM, OM, CF, NDF and ADF, respectively) than in the SBM+SM supplement (445, 423, 25, 102, 38 g/animal/d for DM, OM, CF, NDF and ADF, respectively). Two animals from each species were fed either supplement in a cross-over design in two periods. Each period lasted for four weeks. In situ and in vivo digestibility studies were carried out, followed by the determination of rumen volume and rumen fluid dilution rate. The results showed that straw DM and total DM intakes of goats (average of $48.7g/kg\;W^{0.75}$, $72.7g/kg\;W^{0.75}$, respectively) were significantly (p<0.01) higher than sheep (average of $3.56g/kg\;W^{0.75}$, $61.6g/kg\;W^{0.75}$, respectively), but OM, N and GE intakes were not significantly different between the two animal species. When the effect of supplements was compared, animals fed SBM+SM supplement had significantly (p<0.001) higher DM, OM and GE intakes than animals fed SBM supplement. Potential degradabilities of rice straw DM were significantly (p<0.01) higher in goats (average of 48.8%) than in sheep (average of 46.1 %). The supplements had no significant effect on the potential degradabilities of DM, OM and NDF, but they had a significant (p<0.05) effect on the degradation rates of DM and NDF. The addition of sago meal in the diet reduced the degradation rates of DM and NDF of rice straw in the rumen. Potential degradability of DM of soybean meal was not significantly different between animal species as well as between supplements. Sago meal was highly degradable. At 24 h of incubation in the rumen, 90-95% of DM loss was observed. There was a significant interaction between animal species and supplements in the in vivo digestibility of ADF and GE. In animals fed SBM supplement, the in vivo digestibility of ADF was significantly (p<0.05) higher in goats ($50.6{\pm}4.22%$) than in sheep ($44.4{\pm}3.21%$), but digestibility of GE was significantly (p<0.05) higher in sheep ($70.2{\pm}1.93%$) than in goats ($63.0{\pm}3.07%$). The digestibility values of CP and OM were significantly (p<0.05) higher in sheep when compared to goats. Animals fed SBM+SM supplement showed significantly (p<0.05) higher DM and OM digestibility values than animals fed SBM supplement, but digestibility values of CP were significantly (p<0.05) higher in animals fed SBM supplement. Differences in in vivo digestibility values of CF and NDF were not significantly different between animal species or supplements. Water intake, rumen volume ($1/kg\;W^{0.75}$), rumen fluid dilution rate and mean retention time were similar between the two animal species. However, rumen fluid dilution rate and mean retention time was significantly (p<0.01) affected by supplements. Animals fed SBM+SM had faster rumen fluid dilution rate and consequently shorter mean retention time.

• The Korean Journal of Emergency Medical Services
• /
• v.8 no.1
• /
• pp.87-104
• /
• 2004

This study selected the fifth and sixth graders of elementary school in Jeollanamdo who can express their opinions of safety consciousness and understand the items of questionnaire as the population. It selected 10 elementary schools under the supervision of Jeonnam Board of Education and sampled 700 students randomly from 2-3 classes in the 5th and the 6th grade. One preliminary survey was conducted to revise and complement the contents and forms of questionnaire with 70 students of a school from Apr. 1 to 6, 2004 and this study was conducted from Apr. 10 to 30, 2004. Data of this study were collected by explaining the purport of study to subjects after obtaining approval of principal and teacher of the school and distributing questionnaires. Total 700 questionnaires were distributed and 681 were collected (97%) and 602 were used for final analysis except 79 lacking responses. The results of this study are as follows. According to demographical characteristics of subjects, 'male' students were 302(50.%) and 'female' students were 300(49.8%) by sex and 'the 5th graders' were 285(47.3%) and 'the 6th graders' were 317(52.7%) in grade distribution. Residents at 'apartment house' were 406(67.4%) in residence type, 'going to school by foot' was 477 students(79.2%), 'high school graduates' were 297(49.3%) in fathers' education, 'high school graduates' were 366 (60.8%) in mothers' education, 'professional and office workers' were 231(38.4%) in fathers' job, 'full-time workers' were 283(47.0%) in mothers' job, and the number of siblings was one except myself in 343 students(57.0%). Respondents on the level of class showing 'good' were 340(56.5%) and those on the degree of adaptation to school life showing 'active' were 349(58.0%). On the characteristics related to safety education, 360(59.8%) responded it was 'very necessary', on the frequency of safety education at school for last one year, 339(56.3%) responded they had 'once or twice', on the frequency of safety education by parents, 279(46.3%) responded they 'often' had it, on the level of safety practice by parents, 347(57.6%) responded they practiced it 'frequently', on the source of knowledge of safety, 223(37.0%) responded they got it from 'parents, siblings and relatives', on the degree of recognizing the need of safety education textbooks, 295(38.5%) responded 'it was needed', on the recognition of necessity of teacher for safety education, 271(45.0%) answered it was very necessary', and on the recognition of qualification of teacher for safety education, 370(61.5%) answered it was 'paramedic'. The mean score of safety consciousness of subjects was 2.72 (SD. 21) of full score 3, having high score over mean score. According to each area, the area showing the highest safety consciousness was safety of fire(2.83), followed by home safety(2.76) and first-aid treatment(2.76), traffic safety(2.71), play and leisure safety(2.66) and school safety(2.56). Items showing statistical differences in the degree of safety consciousness according to demographical characteristics were sex(t=-3.11, p=.002), education(t=2.33, p=.021) and number of siblings(F=3.729, p=.011). In the difference of safety consciousness between both sexes, 'female' students(2.75) showed higher safety consciousness than 'male' students (2.69), and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of play and leisure safety, traffic safety, fire safety and first-aid treatment. According to the differences of safety consciousness by grade, 'the fifth graders'(2.74) showed higher safety consciousness than 'the sixth graders'(2.70) and the former also showed higher safety consciousness than the latter in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of fire safety and home safety. In the safety consciousness by the number of siblings, 'single son or daughter' (2.78) was highest and their safety consciousness was also highest in all six areas of school safety, play and leisure safety, traffic safety, fire safety, home safety and first-aid treatment, and there were statistical differences in the areas of school safety, fire safety and home safety, There were statistically remarkable differences in degree of adaptation to school life (F=15.349, p=.000) and perceived schooling level(F=9.552, p=.000). According to the degree of safety consciousness related to characteristics of safety education, there were statistical differences at the degree of recognizing the need of safety education(F=9.797, p=.000), degree of safety education at school(F=2.595, p=.006), degree of safety education by parents(F=12.709, p=.000), degree of practicing safety by parents(F=17.579, p=.000), source of knowledge of safety education (F=2,715, p=.044), necessity of safety education textbooks(F=3.972, p=.008), need of safety teacher(F=4.137, p=.006) and qualification standard of safety teacher(F=3.016, p=.029).

• Korean Journal of Ecology and Environment
• /
• v.33 no.3 s.91
• /
• pp.222-229
• /
• 2000

Spatial and temporal variation of phosphorus in response to intensity of summer monsoon was evaluated in Taechung Reservoir during 1993${\sim}$1994. Total phosphorus (TP) averaged 31 ${\mu}$g/l during the study and varied from 6 to 197 ${\mu}$g/l. Concentrations of TP were highest in the headwaters during the monsoon of July${\sim}$August 1993, and these values were mainly made of particulate P and were closely associated (R$^{2}$=0.74, p<0.001) with high inorganic suspended solids (NVSS). In-lake TP in the headwaters was mainly influenced by the watershed runoff and declined toward the dam. Values of TP downlake was only one-fifth of the peak in the headwaters and had no correlation with NVSS. In 1994, inlake TP was markedly lower relative to 1993 and showed low spatial and temporal variation. Maximum TP during monsoon 1994 in the headwaters and mid-lake was 72% and 52% lower, respectively, than in those two zones in 1993 whereas TP downlake was similar between the two years. These results suggest that temporal variation downlake is much less influenced by seasonal inflow compared to the haedwaters. In 1993, mean TP before fall overturn, based on average value for all sites, was significantly (t=5.99, p<0.001) greater than the mean after fall overturn, whereas in 1994 mean TP after fall overturn (32 ${\mu}$g/l) was greater. This outcome indicates that in 1993 major P-input originated from the external source from the watershed during the intense monsoon, whereas in 1994 internal processes dominated during the weak monsoon. Overall data suggest that annual budget of inlake P is regulated by intensity of the summer monsoon, and phosphorus data measured at single site near the dam or headwater zone may not be represent seasonal trends of the system due to large spatial variation of Taechung Reservoir.

• Communications of Mathematical Education
• /
• v.26 no.3
• /
• pp.251-271
• /
• 2012

The purpose of this study is: 1) to determine error sources and the effects of each error source, 2) to investigate optimal measuring conditions from holistic and analytic scoring methods, and 3) to compare the value of reliability between Cronbach's alpha and the generalizability coefficient in self-introduction letter and teacher's recommendation letter based on the generalizability theory in identification of mathematical gifted students by observations and nominations. Data of this study were collected from the science education institute for the gifted attached to the university located within in a capital city for the 2011 academic year. Scores form two raters using holistic and analytic scoring methods in both assessment types were used. The results of this study were as follows. First, as to both assessment types, error sources for people were relatively large regardless of scoring methods. However, error sources for raters in holistic scoring methods had a more significant impact than those of analytic scoring methods. Second, to set optimal measuring conditions in the self-introduction letter and teacher's recommendation letter, if we fixed the number of raters into 2 based on holistic scoring methods, at least 5 and 10 content domains were needed, respectively. In addition, the number of items in teacher's recommendation letter should be more than 3 when we fixed the number of content domains into 4, and the number of items in self-introduction letter should be more than 8 when we fixed the number of content domains into 6 using analytic scoring methods. Third, Cronbach's alpha having only a single source of errors was higher than the generalizability coefficient regardless of assessment types and scoring methods. Hence we recommend that generalizability coefficient based on various error sources such as raters, content domains, and items should be considered to keep a satisfactory level of reliability in both assessment types.

• Korean Journal of Environmental Biology
• /
• v.38 no.3
• /
• pp.404-415
• /
• 2020

We investigated the seasonal variations in growth and physiological responses of the kelp species Ecklonia cava to different nitrogen sources to establish indoor culture conditions for mass production. Ecklonia cava was cultivated for 10 days in 16 combinations of seawater temperatures (15, 17, 21, and 25℃) and different nitrogen sources (control; NH-NH₄⁺ 100 μM; NO-NO₃^- 100 μM; and NHNO-NH₄⁺ 50 μM+NO₃^- 50 μM). The growth and growth rate of the blade were affected by temperature. The mean fresh weight and area-based daily growth rate were the highest (5.8±0.5 and 6.6±0.5% day^-1, respectively) at 15℃ and the lowest (2.2±0.2 and 3.0±0.3% day^-1, respectively) at 25℃. The daily growth rate was the highest in the NH and NO treatments and lowest in the control. The nitrate reductase activity of E. cava varied with water temperature (season). The highest activity was in the control (1.32±0.10 μmol NO₂^- g^-1 dry weight h^-1) and the lowest was in the NH treatment (0.25±0.02 μmol NO₂^- g^-1 dry weight h^-1). The photosynthetic pigment concentrations reached a maximum value in the NHNO treatment and a minimum value in the control. These results showed that water temperature played an important role in the cultivation of E. cava and that a single supply of NH₄⁺ or NO₃^- may induce the accelerated growth of E. cava. The growth and physiological responses of E. cava to different nitrogen sources during each season provide valuable information for determining the optimal nitrogen source in E. cava cultivation under indoor conditions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2004.04a
• /
• pp.5-9
• /
• 2004

In this paper, we studied the OCT(Optical Coherence Tomography) system which it has been extensively studied because of having some advantages such as high resolution cross-sectional images, low cost, and small size configuration. A basic principle of OCT system is Michelson interferometer. The characteristics of light source determine the resolution and the transmission depth. As a results, the light source have a commercial SLD with a central wavelength of 1,285 nm and FWHM(Full Width at Half Maximum) of 35.3 nm. The optical delay line part is necessary to equal of the optical path length with scattered light or reflected light from sample. In order to equal the optical path length, the stage which is attached to reference mirror is moved linearly by step motor And the interferometer is configured with the Michelson interferometer using single mod fiber, the scanner can be focused of the sample by using the reference arm. Also, the 2-dimensional cross-sectional images were measured with scanning the transverse direction of the sample by using step motor. After detecting the internal signal of lateral direction at a paint of sample, scanner is moved to obtain the cross-sectional image of 2-demensional by using step motor. Photodiode has been used which has high detection sensitivity, excellent noise characteristic, and dynamic range from 800 nm to 1,700 nm. It is detected mixed small signal between noise and interference signal with high frequency After filtering and amplifying this signal, only envelope curve of interference signal is detected. And then, cross-sectional image is shown through converting this signal into digitalized signal using A／D converter. The resolution of the OCT system is about 30$\mu\textrm{m}$ which corresponds to the theoretical resolution. Also, the cross-sectional image of ping-pong ball is measured. The OCT system is configured with Michelson interferometer which has a low contrast because of reducing the power of feedback interference light. Such a problem is overcomed by using the improved inteferometer. Also, in order to obtain the cross-sectional image within a short time, it is necessary to reduce the measurement time for improving the optical delay line.

• Korean journal of applied entomology
• /
• v.7
• /
• pp.5-13
• /
• 1969

Present system of seed potato production in Korea has several weak points and consequently has difficulties in covering annual shortage of 60,000 tons of seed potatoes. The author has an opinion that this so called 'High land system' of seed potato production adopted by the Government should be replaced by the 'Coastal area system' which is proposed by the author and has many advantages over present 'High land system'(2). In coastal areas where enormous acreage of rice paddies are spread, mostly around the villages. the primary host plants of the vectors are found. Therefore, the only source of aphid vectors are limited to the villages. The farmer's houses scattered more sparsely also have minor importance. In the previous paper(2), the author reported that the aphid vector populations were lower in the coastalareas than at Taegwanryong where the Alpine Experiment Station for the production. of seed potatoes is located. However, the number to vectors at Okku showed rather high density, where the trap was placed at the distance of 200 m from a village where peach and Hibiscus trees, the primary hosts of Myzus pesrsicae and Aphis gossypii were grown. To clarify the flight distance from the source of the aphid vectors, a trial was carried out in the Kwanghwal area, Kimje-gun, Cholla-pukto. on the western coast. 13 traps were placed at four directions and the distances between the traps were 250 m. (Fig. I) The traps 'Were operated from June 21 to October 31. The results are shown in Table 1. A total of some 70 species of aphids were found, including 5 speceis of potato virus vectors. The vectors are as follows: I. Myzus persicae (Sulzer) 2. Aphis gossypii Glover 3. Aulacorthum solani (Kaltenbach) 4. Lipaphis erysimi (Kaltenbach) 5. Macrosiphoniella sanborni (Gillette) Out of a total of 12,797 aphids, 5,187$(48\%)$ vectors were found. The trap catches at the 13 locations are shown in Fig. 2 and the numbers of the vectors at each location for each vector, except Macro-siphoniella sanborni. of which only a single individual was caught, are shown in Fig. 3-6. Number of vectors at C (3,279) (Centre of the village) is considerably higher than that at Suwon (763); however, EI. SI. WI and NI. where the distanecs from Care 250 m, showed lower numbers of vectors than that at Taegwanryong (347). The number of vectors at NI was rather than at the other 3 locations at the distance of 250m from the village. This was because C was in the southern part of the village. Consequently NI was much closer to the village than the other 3 locations of the same distance from C. Numbers of catches of the most important vector. Myzus persicae, are shown in Fig.3. The distribution pattern is typical except $S-2\;and\;W_3$, where several farmer's houses were found. If only the rice paddies were found in these locations. the numbers of the vectors would be small as the distances increase. Numbers of catches of the other 3 vectors are shown in Fig. 4-6. From these results. the author has drawn the following conclusions: 1. The aphid vector sources at the rice paddy belt in the western coast are the villages. 2. The vector densities at the locations where the distances are 250 m from the centre of the village are lower than that at Taegwanryong. 3. The vector densities become gradually lower as the distances from the centre of village increase. However. depending on the host plant situation at each location, the vector densities are variable. These minor sources of aphid vectors may be eliminated so that seed potatoes can be grown. 4. Thus. under the direction of specialists, fields suitable for seed potato production can be found in the coastal areas.

• Applied Biological Chemistry
• /
• v.16 no.1
• /
• pp.1-11
• /
• 1973

In order to obtain the basic informations on the production of single cell protein from ethanol, 145 yeast strains utilizing ethanol as a sole carbon source were isolated from 32 soil samples in Korea. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimum culture condition, utilization of other carbon sources and the cultural characteristics for the selected yeast, and the chemical analysis of the yeast cell composition, and utilization of ethanol by the selected yeast were investigated. All the culture was carried out in the shaking flasks. The results obtained were as follows: 1. The selected yeast strain was identified as Debaryomyces nicotianae-SNU 72. 2. The optimum composition of the medium for the selected yeast is : Ethanol 40 ml, Urea 0.5 g, Potassium phosphate (dibasic) 0.5 g, Ammoium phosphate (monobasic) 0.15 g, Magnesium sulfate 0.05 g, Calcium chloride 0.01g, Yeast extract 0.005 g, Tap water 1000 ml. 3. The optimum pH was 5.0-5.5, the optimum temperature $30-33^{\circ}C$ and the aerobic state was unimportant. 4. Utilization of methanol, n-propanol, iso-propanol, n-butanol, iso-butanol, tert-amyl alcohol and acetic acid by the selected yeast was very weak. So substitution of the subtrate was thought to be impossible. 5. Studies on the propagation of the yeast cells showed that the lag phase of the yeast cells lasted 16 hours, and the logarithmic growth phase extended 16 to 28 hours. The specific growth rate was about $0.19\;hr^{-1}$ and the doubling time was 3.6 hours during the logarithmic growth phase. 6. As the result of the chemical analysis of the dry yeast cells, the content rate of the crude protein was 55.19 %, the content of others was similar to the average content of the yeast component. 7. After 34 hours cultivation, under the optimum culture condition investigated, the dry cell yield against the amount of the added ethanol was 53.4 % (W/V%), the dry cell yield against the amount of the utilized ethanol was 73.6 % (W/V%), the evaporation rate of ethanol was about 19.1 %.

• Journal of Life Science
• /
• v.32 no.7
• /
• pp.510-522
• /
• 2022

In this study, to biosynthesize PHA with properties more similar to polypropylene, a Bacillus sp. EMK-5020 strain that biosynthesized poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was isolated from soil. Bacillus sp. EMK-5020 strain biosynthesized PHBV containing 1.3% 3-hydroxyvalerate (3HV) using reducing sugar contained in Makgeolli lees enzymatic hydrolysate (MLEH) as a single carbon source. As the amount of propionic acid, which was added as a second carbon source, increased, the content of 3HV also increased. PHBV containing up to 48.6% of 3HV was synthesized when 1.0 g/l of propionic acid was added. Based on these results, the strain was cultured for 72 hr in a 3 l fermenter using reducing sugar in MLEH (20 g/l) and propionic acid (1 g/l) as the main and secondary carbon sources, respectively. As a result, 6.4 g/l DCW and 50 wt% of PHBV (MLEH-PHBV) containing 8.9% 3HV were biosynthesized. Through gel permeation chromatography and thermogravimetric analysis, it was confirmed that the average molecular weight and the decomposition temperature of MLEH-PHBV were 152 kDa and 273℃, respectively. In conclusion, the Bacillus sp. EMK-5020 strain could biosynthesize PHBV containing various 3HV fractions when MLEH and propionic acid were used as carbon sources, and PHBV-MLEH containing 8.9% 3HV was confirmed to have higher thermal stability than standard PHBV (8% 3HV).