• Journal of Aquaculture
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• v.3 no.1
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• pp.89-125
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• 1990

In order to improve top shell seed production techniques spawning and larvae rearing were done in rearing tanks. Growth of young top shell in the nursing ground were also investigated. For induced spawning, top shells were maintained in still water during night time. Then they were treated with ultra violet iradiated sea water after dried up in air for 60 minutes. Spawning rate were 10 to $39.77\%$. It was found that young top shells moved in the growing grounds from nursing grounds when they reached approximately 30-40mm in shell heignt. Among main food algae for top shell in the natural growing grounds, sea mustard were melted away during June. Therefore, presence of another food algae such as Ecklonia cava or Sargassum spp. seems to be the main limiting factor for survival of top shell during summer. The tolerance of top shells ranging from 30mm to 60mm to low density of seawater for were tested at the temperature between 29.5 and $31.4^{\circ}C$. Hundred percent mortality occoured in 20, 55 and 90 hours after first stocking at the specific gravity of 1.010, 1.015, and 1.020, respectively.

• Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.7.1-7.8
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• 2020

Background: To minimize the use of antibiotics and to obtain a more sustainable fish culture and aquaculture industry, development of alternative natural source of immunostimulant to replace antibiotic in aquafeed is highly needed. Objective: Dietary inclusion effect of yacon (YC), ginger (GG), and blueberry (BB) on growth, body composition, and disease resistance of black rockfish against Vibrio anguillarum was compared to ethoxyquin (EQ). Methods: Four hundred eighty juvenile (an initial weight of 4.2 g) fish were randomly distributed into 12 of 50 L flowthrough tanks (forty fish per tank). Four experimental diets were prepared; the control (Con) diet with 0.01% EQ inclusion, and YC, GG, and BB diets at 1% each additive inclusion. Each additive was included into the experimental diets at the expense of wheat flour. Each diet was assigned to triplicate tanks of fish and hand-fed to satiation twice daily for 8 weeks. At the end of 8-week feeding trial, 20 fish from each tank fish were artificially infected by intraperitoneal injection with 0.1 mL of culture suspension of pathogenic V. anguillarum containing 3.3 × 10⁶ cfu/mL respectively. Fish were monitored for the following 8 days after V. anguillarum infection and dead fish were removed every 6 h for the first 4 days and 12 h for the rest of the study. Results: Weight gain, specific growth rate (SGR), and feed efficiency ratio (FER) of fish fed the YC diet was higher than those of fish fed all other diets. However, feed consumption, protein efficiency ratio, and protein retention was not affected by dietary additive. Moisture, crude protein, and crude lipid content of the whole body of fish were affected by dietary additive. Analysis of the Kaplan-Meier survival curves showed that survival of fish fed the YC, BB, and GG diets was higher than the Con diet. Conclusion: Oral administration of YC can improve not only weight gain, SGR, and FER of black rockfish, but lower mortality of rockfish at occurrence of V. anguillarum.

• International Journal of Industrial Entomology and Biomaterials
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• v.23 no.2
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• pp.215-221
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• 2011

To establish an indoor-rearing system for the Large Copper butterfly, $Lycaena$ $dispar$ and the Small Copper butterfly, $Lycaena$ $phlaeas$, the effect of temperature, photoperiod and host plants on larval development was investigated. The larvae of $Lycaena$ $dispar$ fed on $Rumex$ $crispus$, whereas the larvae of $Lycaena$ $phlaeas$ ate both $Rumex$ $crispus$ and $Rumex$ $acetosa$. The duration of the larval period of $Lycaena$ $dispar$ was 13.8 days on $R.$ $crispus$ and that, of $Lycaena$ $phlaeas$ was 15.9 days and 15.2 days on $R.$ $acetosa$ and $R.$ $crispus$ respectively. Laboratory experiments show that the Large Copper larvae are able to feed on other $Rumex$ species without harming their overall survival and can utilize these alternative host plants at least as efficiently as their natural host plant. This result suggests that plant chemistry is not responsible for their lack of utilization of the alternative host plants in the wild. Host plant choice by ovipositing females was measured with the two alternative hosts. $Lycaena$ $dispar$ preferred $R.$ $crispus$ to $R.$ $acetosa$, wheareas $Lycaena$ $phlaeas$ preferred $R.$ $acetosa$ to $R.$ $crispus$. Temperature has been proposed as an important determinant of developmental rate, lifespan and mortality in invertebrates. As temperature increased, length of the developmental period gradually decreased. The developmental period of the Large Copper larvae was 11.0 days and 28.5 days at $30^{\circ}C$ and $17.5^{\circ}C$, respectively.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.297-309
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• 2020

Coronaviruses were originally discovered as enzootic infections that limited to their natural animal hosts, but some strains have since crossed the animal-human species barrier and progressed to establish zoonotic diseases. Accordingly, cross-species barrier jumps resulted in the appearance of SARS-CoV, MERS-CoV, and SARS-CoV-2 that manifest as virulent human viruses. Coronaviruses contain four main structural proteins: spike, membrane, envelope, and nucleocapsid protein. The replication cycle is as follows: cell entry, genome translation, replication, assembly, and release. They were not considered highly pathogenic to humans until the outbreaks of SARS-CoV in 2002 in Guangdong province, China. The consequent outbreak of SARS in 2002 led to an epidemic with 8,422 cases, and a reported worldwide mortality rate of 11%. MERS-CoVs is highly related to camel CoVs. In 2019, a cluster of patients infected with 2019-nCoV was identified in an outbreak in Wuhan, China, and soon spread worldwide. 2019-nCoV is transmitted through the respiratory tract and then induced pneumonia. Molecular diagnosis based on upper respiratory region swabs is used for confirmation of this virus. This review examines the structure and genomic makeup of the viruses as well as the life cycle, diagnosis, and potential therapy.

• Animal Bioscience
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• v.34 no.3_spc
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• pp.434-442
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• 2021

Objective: This study aims to evaluate the influence of dietary flavonoids on the growth performance, blood and intestinal profiles, and carcass characteristics of broilers by employing a meta-analysis method. Methods: A database was built from published studies which have reported on the addition of various levels of flavonoids from herbs into broiler diets and then monitored growth performance, blood constituents, carcass proportion and small intestinal morphology. A total of 42 articles were integrated into the database. Several forms of flavonoids in herbs were applied in the form of unextracted and crude extracts. The database compiled was statistically analyzed using mixed model methodology. Different studies were considered as random effects, and the doses of flavonoids were treated as fixed effects. The model statistics used were the p-values and the Akaike information criterion. The significance of an effect was stated when its p-value was <0.05. Results: Dietary flavonoids increased (quadratic pattern; p<0.05) the average daily gain of broilers in the finisher phase. There was a reduction (p<0.01) in the feed conversion ratio of the broilers both in the starter (linear pattern) and finisher phases (quadratic pattern). The mortality rate tended to decrease linearly (p<0.1) with the addition of flavonoids, while the carcass parameter was generally not influenced. A reduction (p<0.001) in cholesterol and malondialdehyde concentrations (both linearly) was observed, while super oxide dismutase activity increased linearly (p<0.001). Increasing the dose of flavonoids increased (p<0.01) the villus height (VH) and villus height and crypt depth (VH:CD) ratio (p<0.05) in the duodenum. Similarly, the VH:CD ratio was elevated (p<0.001) in the jejunum following flavonoid supplementation. Conclusion: Increasing levels of flavonoids in broilers diet leads to an improvement in growth performance, blood constituents, carcass composition and small intestinal morphology.

• Journal of Aquaculture
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• v.4 no.2
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• pp.73-84
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• 1991

Underground sea water is widely utilized for land based aquaculture in Cheju province, Korea nowadays. Salinity of this water($20{\~}30$ ppt) is slightly lower than natural sea water but because of its good water quality and temperature which is maintained at $16{\~}18^{\circ}C$ all year-round, many fish farmers are using this water for finfish culture. To evaluate the possibility of utilizing underground sea water for the seed production of the flounder, Paralichthys olivaeceus, hatching rate of fertilized eggs, survival rate of hatched larvae, and growth rate of the juveniles were tested with various salinity levels ranged from 14.1 ppt to 40.2 ppt. The salinity ranges which showed over $70{\%}$ survival rate for fertilized eggs to hatchout were 33.7 ppt${\~}$40.2 ppt, for hatched larvae to 2-day-old were 20.6 ppt${\~}$40.2 ppt, from 10-day-old to 12-day-old were 27.2 ppt${\~}$40.2 ppt, and from 45-day-old to 47-day-old were 20.6 ppt${\~}$40.2 ppt. Two hundred day old fingerlings showed no mortality when exposured to 7.6 ppt${\~}$40.2 ppt for 2 days. All fish died within 3 days when 45-day-old juveniles were transferred directly from normal sea water to 14.1 ppt sea water. However, they were all survived when transferred first to 20.6 ppt for 3 days then to 14.1 ppt sea water. The highest growth rates of fingerlings reared at 4 different salinities (33.7, 27.0, 31.0, or 15 ppt) were obtained at the 27 ppt group followed by 33.7, 21.0, 15 ppt respectively. The relationship between the days of rearing (X) and the total length of the fingerlings were as follows. $33.7\%$ group : Y=8.8109 + 0.1104X(r=0.999) $27.0{\%}$ group : Y=8.6797 + 0.1208X(r=0.997) $21.0{\%}$ group : Y=8.4081 + 0.1052X(r=0.990) $15.0{\%}$ group : Y=8.4309+ 0.0995X(r=0.990)

• Journal of Preventive Medicine and Public Health
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• v.1 no.1
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• pp.9-23
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• 1968

A survey was conducted by the staff of the College of Medicine and School of Public Health, Seoul National University in cooperation with Seoul Special City from 1 December 1967 through 28 February 1968, on such events as delivery, death, abortion and pregnancy. The survey directed to a total population of 47,811 residing in 9,157 households led us to the following findings: 1. Two year averages of crude birth rate, crude death rate and natural increase rate were 30.1, 5.6 and 24.5, respectively. 2. Of all deliveries, home and hospital deliveries constituted 61.1 per cent and 35.5 per cent, respectively. 3. Deliveries other than hospital deliveries were found to be attended more often by mother-in-laws (26.5 per cent) than by doctors or midwives(23.4 per cent). 4. About 51 per cent of all women having experiences in pregnancy during the last two years had an experience of consulting a doctor at least one time throughout whole period of pregnancy. 5. In most cases scissors were used to cut umbilical cords, of which 71.0 per cent were not sterilized and only 20.3 per cent sterilized. 6. In many cases placenta was incinerated(48.2 per cent) and on many other occasions it was thrown away into water(28.3 per cent). 7. Cement bags(37.4 per cent), gauze and absorbent cotton(29.8 per cent) were found to be most frequently used to receive new-born babies. 8. In 1966 8. 8 per cent of the women had at least one abortion induced and in 1967 the percentage was 9.2 per cent. 9. Nearly all(95.8 per cent) of the induced abortions reportedly were done at doctor's clinics. 10. Of all the abortions induced 65.3 per cent were done by specialists in obstetrics, 30.3 per cent by general practitioners and 2.7 per cent by midwives. 11. Those who experienced spontaneous abortions were 1.9 per cent of all women both in 1966 and 1967. 12. About 9.2 per cent of women investigated were found to be currently pregnant. 13. Age specific death rate turned out to be highest among those under 1 year of age. 14. Ten major causes of death in their order of frequency were: 15. Places of death can be classified into homes(75.3 per cent) and hospitals(13.2 per cent). 16. Method of disposing of corpses comprised burials(54.2 per cent) and cremations(44.6 per cent). 17. Infant, neonatal and hebdomadal mortality rates have been computed at 32.2, 18.9 and 13.7, respectively. 18. Infants were found to have died either at homes(81.5 per cent) or at hospitals(18.5 per cent). 19. Birth registrations had been done for about 18.5 per cent of the dead infants.

• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.347-356
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• 2000

Background : Patients with obstructive sleep apnea syndrome are known to have high long-term mortality compared to healthy subjects because of their cardiovascular dysfunction. The observation of hemodynamic changes by obstructive apneas is helpful when attempting to understand the pathophysiological mechanism of the development of cardiovascular dysfunction in those patients. Therefore, we studied the changes in cardiovascular function with an animal model and tried to obtain the basic data for an ideal experimental model (this phrase is unclear), a requirement for a more advanced study. Methods : Sixteen anesthetized dogs with ${\alpha}$-chloralose delete were divided into two groups : 8 dogs of room air breathing group and 8 dogs of oxygen breathing group. We measured $PaO_2$, $PaCO_2$, heart rate, cardiac output, mean femoral artery pressure, and mean pulmonary artery pressure at specified times during the apnea-breathing cycle before endotracheal tube occlusion (baseline), 25 seconds after endotracheal tube occlusion (apneic period), 10 seconds (early phase of postapneic period, EPA) and 25 seconds (late phase of postapneic period, LPA) after spontaneous breathing. Results : In room air breathing group, the heart rate significantly decreased during the apneic period compared to that at baseline (P<0.01) and increased at EPA and LPA compared to that during the apneic period (P<0.01). But, the heart rate showed no significant changes during apneic and postapneic periods in the oxygen breathing group. Cardiac output tended to decrease during apneic period compared to that at baseline, but was statistically significant. Cardiac output significantly decreased at LP A compared to at baseline (P<0.01). Mean femoral artery pressure was significantly decreased at during apneic period compared to that at baseline (P<0.05). Conclusion : Through this experiment, we were partially able to understand the changes of cardiovascular function indirectly, but delete new experimental animal model displaying physiological mechanism close to natural sleep should be established, and the advanced study in the changes of cardiovascular function and their causes should be continued.

• Korean journal of applied entomology
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• v.47 no.2
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• pp.163-168
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• 2008

Temperature dependent development of Tetranychus. urticae Koch was studied on the leaf of eggplant at 17, 22, 27, 32 and $37^{\circ}C$. T. urticae showed a minimum mortality at $27^{\circ}C$ and it increased at higher or lower temperatures than $27^{\circ}C$. The hatchability was low at 17 and $37^{\circ}C$. The duration of development decreased with increasing temperatures i.e., 5.3d at $37^{\circ}C$ and 25.8d at $17^{\circ}C$. Linear regression analysis of temperature vs. rate of development yielded the higher $r^2{\geq}0.88$ resulting in a good fit of the estimated line in the range of $17{\sim}37^{\circ}C$. Developmental zero temperature was $12.5^{\circ}C$ for the entire immature stage of female and $12.8^{\circ}C$ for that of male. Thermal constants were 80.5 and 74.7 degree days for those of female and male, respectively. Adult life span and oviposition period decreased with increasing temperatures. The number of eggs laid per female peaked at 141.0 eggs at $27^{\circ}C$, while that was a minimum 78.0 eggs at $37^{\circ}C$. Rate of hatchability, ratio of female, and $R_o$ were increased up to $27^{\circ}C$, and than declined thereafter. Intrinsic rate of natural increase (Rm) increased with rising temperatures and showed a maximum 0.5652 at $37^{\circ}C$. Also, ${\lambda}$ increased with increasing temperature. Doubling time (Dt) and generation time (T) decreased with increasing temperature.

• Clinical and Experimental Pediatrics
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• v.51 no.4
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• pp.343-350
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• 2008

Asthma and allergic diseases are one of the most common disorders in children. Due to its increased prevalence, as well as the increased morbidity and mortality from these diseases, asthma and allergic diseases have come to be recognized as a major worldwide public health issue. In addition, socioeconomic burden of asthma and allergic diseases has increased in Korea also. The International Study of Asthma and Allergies in Childhood (ISAAC) investigated the worldwide prevalence of asthma and other allergic diseases using simple standardized methods because of the comparison of asthma and allergic diseases between the countries. In Korea, several epidemiologic studies have been conducted to determine the prevalence of asthma in children. Although these studies showed increased prevalence of asthma among Korean children (from 3.4% in 1964 to 10.1% in 1989), these findings were based on data from small numbers of subjects. The first Nationwide Study of Asthma and Allergies in Korean Children, which utilized the Korean version of ISAAC written and video questionnaire, was conducted in 1995 and the second Nationwide Study of Asthma and Allergies in Korean Children was conducted in 2000, directed by the Korean Academy of Pediatric Allergy and Respiratory Diseases. We report here the prevalence of asthma and other allergic diseases in Korean children and adolescents, and show the changes that occurred over this 5 year period. We also describe the risk factors for development of these diseases in Korean children. We developed Korean versions of the ISAAC written (WQ) and video (AVQ) questionnaires for allergic diseases. In 1995, the enrolled population consisted of 25,117 children selected from 34 elementary school and 14,946 children selected from 34 middle school across the nation, the response rate was 94.8%. In 2000, 27,831 children selected from 34 elementary school and 15,214 children selected from 34 middle school, and the response rate was 96.4%. From these studies, we can confirm that increase of the prevalences of asthma, allergic rhinitis, and atopic dermatitis in Korea, except the prevalence of food allergy. Especially, the video questionnaire showed increases in the lifetime and 12 month prevalence rates of wheeze at rest, exercise-induced wheeze, nocturnal wheeze, nocturnal cough, and severe wheeze over this period of time in middle school children. In addition, the increase of prevalences of symptoms, diagnosis and treatment of atopic dermatitis was noted significantly. Risk factor analysis showed that body mass index (BMI), passive smoking and living with a dog or cat were associated with higher risk of wheeze. Also the occurrence of fever during infancy and the frequent use of antibiotics were associated with the risk of wheeze. In conclusion, during the 5 year period from 1995 to 2000, the prevalences of asthma, allergic rhinitis, and atopic dermatitis has increased in Korean children. BMI, passive smoking, living with a dog or cat, the fever episodes in infancy, and the frequent use of antibiotics in infancy are important risk factors to development of asthma and atopic dermatitis. In the near future, the birth cohort study will be needed to investigate the causes of this increase and the natural course of allergic diseases, then we develop the methods to control asthma and allergic diseases.