• 제목/요약/키워드: duration ratio

검색결과 1,416건 처리시간 0.028초

Studies on the Strength of Briquette Ash Hardened by Cement (연탄재를 시멘트로서 경화(硬化)시켰을 때의 강도(强度)에 관(關)한 연구(硏究))

  • Kim, Seong-Wan
    • Korean Journal of Agricultural Science
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    • 제6권1호
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    • pp.45-55
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    • 1979
  • This study made to find the variation of strengths of briquette ash which were hardened into cement. The briquette ash were mixed with the cement, ((cement (90%)+slaked lime (10%)) and ((cement (80%)+fly ash (20%)) in the ratio of 1:2, 1:3, 1:4, 1:5, 1:7 and 1:9, respectively, and these were compared with the one made of cement plus standard sand in the strengths of compression, tension and bending at the ages of 7 days and 28 days. The results from the study conducted preliminary without studying the economical aspects or duration of the products are summarized as follows: 1. The compressive strengths of mortar made of 1 to 2 ratios of cement to briquette ash, (cement+slaked lime) to briquette ash and (cement+fly ash) to briquette ash were 84%, 90% and 75% at the age of 7 days and 84.9%, 73.5% and 69.8%, respectively of those of Korean Standard values. 2. The compressive strength s of mortar made of 1 to 2 ratios of cement to briquette ash, (cement+slaked lime) to briquette ash and (cement+fly ash) to briquette ash were 69.3%, 75.1% and 41.3% at the age of 7 days and 56.4%, 49%, and 46.5% at the age of 28 days, respectively of the mortar made of standard sand. 3. The tension strengths of mortar made of 1 to 2 ratios of cement to briquette ash, (cement+slaked lime) to briquette ash, and (cement+fly ash) to briquette ash were 64.4%, 47.1% and 35.4% at the age of 7days and 69.6%, 64.8%, and 57.3%, respectively of that of the mort ar produced with standard sand. 4. The bending strengths of mortar made of 1 to 2 ratios of cement to briquette ash, (cement+slaked lime) to briquette ash, and (cement+fly ash) to briquette ash were 46.3%, 65.9% and 39.1% at the age of 7 days and 89.9%, 96.7%, and 85.1%, respectively of that of mortar produced with standard sand. 5. The bending strength of the mortar was lower than that of cement mortar, when the briquette ash were harqened into cement. However, the mortar produced by such method seemed to be used as the secondary products of cement or concrete. The additional usefullness of the hardened biquette ash can be found in contributing toward the solving the various pollution problems, the saving the labor costs needed to clean-up waste materials, and the saving the construction materials.

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Effect of Temperature on Development and Life Table Parameters of Tetranychus urticae Koch (Acari: Tetranychide) Reared on Eggplants (가지에서 온도별 점박이응애 발육특성 및 생명표 통계량)

  • Kim, Ju;Lee, Sang-Koo;Kim, Jeong-Man;Kwon, Young-Rip;Kim, Tae-Heung;Kim, Ji-Soo
    • Korean journal of applied entomology
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    • 제47권2호
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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.

A Studs on Exposure to Organic Dust and Ammonia in Poultry Confinement Buildings (일부 육용 양계 농업인의 유기먼지와 암모니아 노출에 관한 연구)

  • Shin, Cheol-Lim;Lee, Kyung-Suk;Kim, Kyung-Ran;Kang, Tae-Sun;Paik, Nam-Won
    • Journal of agricultural medicine and community health
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    • 제29권2호
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    • pp.303-314
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    • 2004
  • Objectives: This study was carried out to assess exposure levels of organic dusts and ammonia in poultry farms in Korea. Methods: A total of six poultry farms were investigated. The farms were located in Namwon, Chonlabuk-do and in Kae-San, Chungchongbuk-do. This study consisted of a questionnaire and measuring organic dusts and ammonia. The questionnaire included the characteristics of the farms, work patterns and the tasks of the poultry farms. Results and Conclusions: The farmers raised the chickens 45 times a year and the average number of years in the poultry farm were eight years ranging from 2 to 12 years. They worked for seven days per week and the average hours spent caring the chickens are 6.3 hours per day. The duration of staying in the confinement buildings was 3.3 hours per day. The work time in summer was longest. The feed and the water supply systems were automatic and the control of ventilation windows used "winch curtain" was semiautomatic. They used mechanical ventilation system in winter and used dilution ventilation system in the other seasons. The geometric mean concentration of total and respirable dust sampled in the poultry confinement buildings was 4.0 mg/$m^3$and 0.9 mg/$m^3$ respectively. The ratio of respirable to total dusts range from 9 to 49 percent. There was no sample exceeding the criteria 10 mg/$m^3$ for total dust and 3 mg/$m^3$ for respirable dust in farms. The criteria have been recommended by Korean Ministry of Labor and American Conference of Governmental Industrial Hygienist. The personal respirable dusts measured during a circle work averaged geometric mean concentration 1.4 mg/$m^3$ Two personal samples were exceeded the threshold 3 mg/$m^3$. There was a positive relation between an index and the personal samples of respirable dusts($R^2$=0.98). The index is calculated by multipling the total number of chickens in the farm by the age of the chickens and then dividing by the volume of the confinement building. The geometric mean concentration of area and personal ammonia samples was 23.3 ppm and 22.2 ppm, respectively. Some of the ammonia samples, both area and personal samples, exceeded the short term exposure limit value 35 ppm.

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THE COMPARATIVE STUDY ON THE SEDATIVE EFFECT OF DIFFERENT INTRAVENOUS MIDAZOLAM DOSAGES FOR PEDIATRIC DENTAL PATIENTS (소아환자의 Midazolam의 정맥투여 용량에 따른 진정 효과에 관한 비교연구)

  • Kim, Eun-Young;Kim, Jong-Soo;You, Seung-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • 제32권3호
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    • pp.416-426
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    • 2005
  • Intravenous sedation have many advantages of rapid onset and recovery, ability of control sedation levels and duration through titration. Midazolam is most commonly used intravenous medication for sedation in pediatrics, endoscopy, oncologic procedures and so on. But in dentistry, midazolam intravenous sedation is usually for adult, and there are few reports for children. Todays, children who need sedation become more and older, intravenous sedation technique is going a matter of concern in pediatric dentistry. The purpose of this paper is to evaluate the efficacy of sedation and clinical success for different initial dosage of midazolam in intravenous sedation for pediatric dental patients. 16 healthy children (male 10, female 6), mean age $54.7{\pm}10.7$ months, who needed at least two separate treatment visits requiring local anesthesia were chosen for this study. Every children were taken 0.3mg/kg, maximum 5mg of midazolam by intramuscular route, and then 30~50% $N_2O-O_2$ for 10 minutes was given. On every visits, one of the following 2 different initial dosage was given by intravenous route : (1) Group I : 0.1mg/kg Midazolam (2) Group II : 0.2mg/kg Midazolam. Additional dosage was half of the first dose. Physiologic parameters (oxygen saturation, heart rate, respiratory rate, end-tidal carbon dioxide pressure) was recorded by ten procedure steps. Behavior was videotaped and rated using Ohio State University Behavioral Rating Scale and Automated Counting System by one investigator, blind to administered dosage. After the treatment, operator evaluated the clinical success. Physiologic parameters were stable and within normal range during treatment in both groups. The analyzed sedative effect, in behavioral evaluation, ratio of favorable Quiet was higher in group II, and clinical success rate of group II was better than group I. Induction time was rapid in group II, and recovery time was rapid in group I. And there was no statistically difference between two groups in every results.

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Thyroglossal Duct Cyst and Fistula (갑상설관 낭포 및 루)

  • 최종욱;김한상;안문성;김춘길;주양자
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 대한기관식도과학회 1981년도 제15차 학술대회연제순서 및 초록
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    • pp.10-10
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    • 1981
  • The thyroglossal duct cyst is relatively rare disease that derived congenitally from the remnant of thyroglossal duct and that was found anywhere from the foramen cecum to pyramidal lobe of thyroid. We studied the 62 cases of above disease who admitted and operated at E.N.T. dept. of N.M.C. for 20 years since 1961 to 1980 on the clinical and histopathological aspect, and we concluded following results. 1. In the age distribution, 45 cases(72.6%) were under 20 years, and in the age distribution of the known on-set of symptoms, 26 cases(58.0%) were under 10 years. In the duration, 23 cases(37.0%) were under 1 year. The sex ratio of male to female revealed 1.2:1. 2. The palpable mass were complained at 48 cases(77.4%) and 14 cases(22.6%) complained of the discharge from sinus tracts and the other complaints were dysphagia and odynophagia, etc. 3. In location 55 cases (88.7%) were at midline, 1 case(1.6%) was at right and 6 cases(9.7%) were left sided. And 47 cases(75.8%) were situated at infrahyoid region, 11 cases(17.7%) at suprahyoid, 3 cases(4.8%) at suprasternal, only 1 case(1.6%) at intralingual region. 4. In 27 cases formed fistulae, spontaneous occurrance were 7 cases and artificial occurrance were 20 cases. 5. In histopathologically among 41 cases preserving available slides, 5 cases(12.2%) had single duct and 20 cases(48.8%) had multiple accessory ducts, but 16 cases were impossible to detect the ducts. The lining epithelium composed of chiefly respiratory and squamous epithelium. 15 cases had inflammatory reaction at periductal area and 7 cases had around the cysts. The ectopic thyroid tissue was found on 6 cases(14.6%) and 1 case had the follicular adenoma. 6. In the recurrance rate among 43 cases performed sistrunk type operation, 2 cases (4.6%) recurred, and among 19 cases performed simple removal of cysts, 4 cases (21.1%) recurred.

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A Prospective Study on Attitude of Professional Student toward Population Related Issues in Korea (대학전공별(大學專攻別) 전문직학생(專門職學生)들의 인구관련문제(人口關聯問題)에 대한 연차적(年次的) 변화(變化) 연구(硏究))

  • Lee, Kyung-Sik;Kim, Hwa-Joong
    • Journal of Preventive Medicine and Public Health
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    • 제9권1호
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    • pp.11-24
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    • 1976
  • This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.

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A Basic Study on the Euryale ferox Salisbury for Introduction in Garden Pond(II) - Focusing with Soil and Water Conditions - (정원 연못내 가시연꽃(Euryale ferox Salisbury) 도입을 위한 기초연구 II - 토양과 수환경을 중심으로 -)

  • Lee, Suk-Woo;Rho, Jae-Hyun;Park, Jae-Cheol;Kim, Hwa-Ok
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • 제34권3호
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    • pp.28-37
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    • 2016
  • Through the research and analysis on the hydrological environment and soil environment of habitats through documentary and field studies over 14 habitats of Euryale ferox Salisb. within Jeollabukdo, with the objective of acquiring the basic data for forming an environment based on plantation of reservoirs that are composed with Euryale ferox, the following results were obtained. As a result of analyzing the construction period of the habitats of Euryale ferox from a total of 14 places, the average period of duration after construction of all subject reservoirs appeared to be 71.8 years. Moreover, when examining the relationship between the age of reservoirs and eutrophication, it could be judged that at least the eutrophication of subsoil and water environment is not an obstacle to the growth of Euryale ferox grows in habitats that have a reservoir age of approximately 70 years or more. As a result of analyzing the gardening of soil sediment of the Euryale ferox habitats, the component ingredients appeared to be composed of 80.2% of clay, 16.7% of silt and 3.1% of sand, and the soil class pursuant to such was classified as 'heavy clay'. The organic matter contents of soil sediment appeared to be an average of 36g/kg, and there appeared to be no noticeable difference between the habitats and non-habitats of Euryale ferox. The water quality environment of Euryale ferox habitat appeared to be pH 6.5~7.9, concentration of dissolved oxygen to be $1.8{\sim}8.8mg/{\ell}$, concentration of COD to be $6.8{\sim}74mg/{\ell}$, floating materials to be $2.0{\sim}213mg/{\ell}$, total nitrogen to be $0.422{\sim}10.723mg/{\ell}$, and phosphate to be $0.003{\sim}0.126mg/{\ell}$. The average DO concentration of Aedang Reservoir at Jeongeup, Daejeong Reservoir at Imsil, and Myeongdeokji at Gimje with high vitality and green coverage ratio of Euryale ferox appeared to be $3.5mg/{\ell}$, total nitrogen to be $1.33mg/{\ell}$, and concentration of phosphorus-phosphate to be $0.061mg/{\ell}$. When comparing such with the entire average value, the DO and total nitrogen concentration appeared to be rather low, and the phosphorus-phosphate concentration appeared to be higher by two times or more, thus, an in-depth study on the correlation of the vitality of Euryale ferox Salisb. and concentration of phosphorate-phosphorus will be needed in the future.

Clinical Analysis of Primary Varicose Vein - review of 209 cases - (원발성 하지정맥류의 임상적 고찰 - 209례 보고 -)

  • Lee, Yuen-Jae;Park, Chul;Kim, Jong-Seok;Kim, Han-Yong;Yoo, Byung-Ha
    • Journal of Chest Surgery
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    • 제34권12호
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    • pp.909-916
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    • 2001
  • Background : Varicose vein is a very common vascular disease and has recently become a matter of concern for thoracic and cardiovascular surgens. Material and Method : We analyzed 209 cases or 269 feet with varicose vein retrospectively, which had been treated in our hospital from April 1999 to December 2000. Result : Male : Female ratio was 1:3(Male : 52 cases, Female : 157 cases), mean age was 42.2$\pm$9.7 years old, mean duration of varicosities was 12.2$\pm$9.7 years, and mean follow up was 14.8$\pm$6.1 months from July 2001. Most common symptom was leg pain(122 cases, 58.4%). Long standing job(44 cases), pregnancy(37 cases), and family history related to varicose vein came to 79.9% as the major predisposing or precipitating factors. Anatomic classifications of main lesion were GSV (greater saphenous vein,126 cases), LSV(lesser saphenous vein,18 cases), and reticular veins and telangiectasias(65 cases). Main treatments were stripping of GSV, stab avulsion, ligation of saphenofemoral junction, sclerotherapy, and conservative treatment. Comparing A group (stripping of GSV) with B group(sclerotherapy of GSV), A group had more complications than B group; however, A group had less recurrences than B group(p 0.05). Comparing C group(stab avulsion of LSV) with D group(sclerotherapy of LSV), there were 2 cases of recurrence in D group; however, there were no statistical differences between the two groups in complication and recurrence(p>0.05). Comparing B group(sclerotherapy of GSV) with E group(sclerotherapy of reticular vein and telangiectasia), there were no differences in complication; however, B group had more recurrences than E group. Post-stripping complications were ankle numbness and tingling(2 cases), ankle pain(2 cases),ankle swelling(2 cases), and wound pain(1 case). Postsclerotherapy complications were thrombophlebitis(1 case) and skin ulcer(1 case). Conclusion: Sclerotherapy for varicose vein involving GSV had more recurrences than stripping for lesions involving GSV. Sclerotherapy for reticular vein and telangiectasia had less recurrences than sclerotherapy for lesion involving GSV. Sclerotherapy is a very convenient method without operation and admission, thus further research is demanded in case of varicose vein involving GSV.

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Severe Pneumonia Caused by 2009 Pandemic Influenza A (H1N1) Virus in Children and Corticosteroid Treatment (소아에서 2009 신종 인플루엔자 A (H1N1) 중증 폐렴과 스테로이드 치료)

  • Sohn, Yu Rak;Kim, Jong Hee;Ma, Sang Hyuk;Lee, Kyung Yil;Kang, Jin Han
    • Pediatric Infection and Vaccine
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    • 제18권2호
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    • pp.193-200
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    • 2011
  • Purpose : The effect of corticosteroid on severe pneumonia caused by 2009 pandemic influenza (H1N1) A virus is controversial. This study was aimed to present the effects of early, short-term corticosteroid treatment for severe pneumonia with this virus infection. Methods : A retrospective analysis was performed on severe pneumonia patients (37 patients) who had severe respiratory distress at presentation requiring oxygen therapy and received intravenous methylprednisolone (MP, 8-10 mg/kg, divided in 4 doses/day for 2-3 days) with oseltamivir. The clinical and laboratory characteristics of the patients were evaluated through the medical records and chest radiographic findings. Results : The mean age and male-to-female ratio of the patients were 6.5${\pm}$2.9 years of age, and 3.4:1 (male 29 patients), respectively. The 5-9 aged group was predominant among the age groups (25 patients, 67.6%). Duration of fever prior to admission was 1.4${\pm}$0.6 days and dyspnea developed within 24 h after beginning of respiratory symptoms in all patients. All patients were previously healthy and received oseltamivir within 48 h. Thirteen patients (35.1%) developed dyspnea during oseltamivir treatment. Following MP infusion, all 37 patients including 13 progressive pneumonia patients during oseltamivir treatment showed an immediate halt in the progression of pneumonic infiltration with rapid clinical improvement. There were no side-effects following steroid use. Conclusion : For severe pneumonia patients, early corticosteroid treatment halted clinical exacerbation, and possibly prevented progression to acute respiratory distress syndrome. Further controlled clinical studies are needed for the role of corticosteroids and antivirals on severely affected patients with influenza virus infections.

Crossbreeding Combination Test for the Production of New Synthetic Korean Native Commercial Chickens (신품종 토종닭 생산을 위한 교배조합 검정시험)

  • Sohn, Sea Hwan;Choi, Eun Sik;Cho, Eun Jung;Kim, Bo Gyeong;Shin, Ka Bin;Lee, Seul Gy;Oh, Ki Suk
    • Korean Journal of Poultry Science
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    • 제48권3호
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    • pp.101-110
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    • 2021
  • In this study, we performed a cross-combination test using offspring from two paternal and five maternal parent stock lines to produce a new synthetic breed of Korean native commercial chickens. The survival rate, body weight, feed intake, and feed efficiency were measured for 10 crosses, with 837 Hanhyup-3 chickens used as a control. Most chickens had brown-based feathers, and there was little difference in color phenotypes among combinations. The average survival rate of the combinations was 94.9%, which was significantly different from that of Hanhyup-3 at 75.3% (P<0.01). There was significant differences in body weight among the combinations at all weeks of age (P<0.01). At 10 weeks of age, the FHHY combination was the heaviest with 2,300 g, while the weight of Hanhyup-3 was 1,922 g. In addition, the weight difference between the male and female chickens was 458 g. As a result of regression analysis, the duration needed to reach 1.9 kg was about 61 days for the FHFY, FHHY, and HFFY combinations, and 70 days for Hanhyup-3, exhibiting a 9-day difference. The average feed conversion ratio of the combinations until 10 weeks was 2.42, which was significantly different from that of Hanhyup-3 at 2.97 (P<0.01). In conclusion, FHHY, FHFY, and HFFY were determined to be the best new breed combinations based on production capacity. When these combinations are used as new commercial breeds, they are expected to increase the average weight by 18% and improve feed efficiency by 19%, as compared to the existing Hanhyup-3 breed.