• Title/Summary/Keyword: population control

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The Trend and Achievements of Forest Genetics Research in Abroad (선진국(先進國)에 있어서의 임목육종연구(林木育種硏究)의 동향(動向))

  • Hyun, Sin Kyu
    • Journal of Korean Society of Forest Science
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    • v.14 no.1
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    • pp.1-20
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    • 1972
  • The trend and achievements of forest genetics research in abroad were investigated through observation tours and reference work and following facts were found to be important aspects which should be adopted in the forest genetics research program in Korea. Because of world wide recognization on the urgency of taking a measure to reserve some areas of the representative forest type on the globe before the extingtion of such forest type as the results of continuous exploitations of the natural forests to meet the timber demand all over the world, it is urgently needed to take a measure to reserve certain areas of natural stand of Pinus koraiensis, Pinus parviflora, Pinus densiflora f. erectra, Abies koreana, Quercus sp., Populus sp., etc. as gene pool to be used for the future program of forest tree improvement. And the genetic studies of those natural forest of economic tree species are also to be performed. 1. Increase of the number of selected tree for breeding purpose. Because of the fact that the number of plus tree at present is too small to carry out selection program for tree improvement, particularly for the formation of source population for recurrent selection of parent trees of the 2nd generation seed orchard it is to be strongly emphasized to increase the number of plus tree by alleviating selection criteria in order to enlarge the population size of plus trees to make the selection program more efficient. 2. Progeny testing More stress should be placed on carrying out progeny testing of selected trees with open pollinated seeds. And particular efforts are to be made for conducting studies on adult/juvenile correlation of important traits with a view to enable to predict adult performances with some traits revealed in juvenile age thus to save time for progeny testing. 3. Genotype-environment interaction Studies on genotype and environment interaction should be conducted in order to elucidate whether the plus trees selected on the good site express their superiority on the poor site or not and how the environment affect the genotype. And the justification of present classification of seed distribution area should be examined. 4. Seed orchard of broad leaf tree species. Due to the difficulty of accurate comparison of growth rate of neighbouring trees of broad leaf tree species in natural stand, it is recommended that for the improvement of broad leaf trees a seedling seed orchard is to be made by roguing the progeny test plantation planted densely with control pollinated seedlings of selected trees. 5. Breeding for insect resistant varieties. In the light of the fact that the resistant characteristics against insect such as pine gall midge (Thiecodiplosis japonensis U. et I.) and pine bark beetle (Myelophilus pinipera L.) are highly correlated with the amount and quality of resin which are known as gene controlled characteristics, breeding for insect resistance should be carried out. 6. Breeding for timber properties. With the tree species for pulp wood in particular, emphasis should be placed upon breeding for high specific gravity of timber. 7. Introduction of Cryptomeria and Japanese Cypress In the light of the fact that the major clones of Cryptomeria are originated from Yoshino source and are being planted up to considerably north and high elevation in Japan, those species should be examined on their cold resistance in Korea by planting them in further northern part of the country.

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Effects of Temperature Conditions on the Growth and Oviposition of Brown Planthopper, Nilaparvata lugens $St{\aa}l$ (온도조건(溫度條件)이 벼멸구의 발육(發育) 및 산란(産卵)에 미치는 영향(影響)에 관한 연구(硏究))

  • Bae, Soon-Do;Song, Yoo-Han;Park, Yeong-Do
    • Korean journal of applied entomology
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    • v.26 no.1 s.70
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    • pp.13-23
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    • 1987
  • This study was conducted to know the effects of temperature conditions on the growth and oviposition of the brown planthopper(BPH), Nilaparvata lugens $St{\aa}l$. Results obtained were to predict the timing of the BPH control by measuring population dynamics of the BPH in response to temperature fluctuations upon migration of the insects in paddy fields. Developmental and ovipositional rates under constant and alternating temperature conditions were observed in a plant growth cabinet. Hatchabilities of eggs of the BPH were the highest at $25^{\circ}C$ and were decreased below or above the optimum temperature. Egg periods were the shortest at $27.5^{\circ}C$ and prolonged with decreasing temperature, but retarded at higher temperature above $30^{\circ}C$. Adult emergence rates were the highest at $27.5^{\circ}C$ and reduced with decreasing temperature, and no adult emerged at $32.5^{\circ}C$ and $35^{\circ}C$. Developmental period of nymph was the shortest at both $27.5^{\circ}C$ and $30^{\circ}C$, but extended with decreasing temperature. Female longevity was increased with decreasing temperature and the male longevity was the shortest at $27.5^{\circ}C$. Preoviposition period was the shortest at $32.5^{\circ}C$, but prolonged with decreasing temperature. It was about 6.5 times longer at $17.5^{\circ}C$ than that at $32.5^{\circ}C$. Number of eggs oviposited per female was the greatest at $25^{\circ}C$, but decreased at the temperature below or above the optimum. Under the same total effective day-degrees, hatchabilty at the alternating temperature was about 10% higher than that at the constant temperature but egg period at the alternating temperature was nearly identical as that at the constant. Under the $22^{\circ}C$ condition, emergence rate was about 8% higher at the alternating temperature than that at the constant, however, at the $28^{\circ}C$, the rate was about 8% higher at the constant than that at the alternating. Nymphal period was about $4{\sim}6$ days longer at the alternating temperature than that at the constant. Under the same total effective day-degrees in adult stage, both longevity and oviposition period were longer at alternating temperature than those at the constant. Number of eggs oviposited per female was also higher at the alternating. Longevities of females reared under $28^{\circ}C$ of constant temperature was the longest no matter what temperatures they were exposed after the emergence. This result seems to be indicating that female longevity is greatly influenced by the temperature to which they were exposed durings immature stages. Preoviposition period was affected by the temperature exposed during the nympal and adult stage whereas the number of eggs oviposited was affected by the temperature during the adult stage only. Based on the results from this study, the developmental threshold temperatures seem to be $14.12^{\circ}C$ for eggs, $14.76^{\circ}C$ for nymphs, $9.62^{\circ}C$ for adults, and $15.95^{\circ}C$ for preoviposition period. Estimated values of the total effective temperature for completing each stage were 141.25 day-degrees for eggs, 167.83 day-degrees for nymphs, 349.64 day-degrees for adults, and 58.60 day-degrees for preoviposition.

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Factors associated with Experience of Diagnosis and Utilization of Chronic Diseases among Korean Elderly : Focus on Comparing between Urban and Rural Elderly (한국 노인의 만성질환 진단경험 및 의료이용에 관련된 요인 : 도시와 농촌 간 비교를 중심으로)

  • Lee, Min Ji;Kown, Dong Hyun;Kim, Yong Yook;Kim, Jae Han;Moon, Sung Jun;Park, Keon Woo;Park, Il Woo;Park, Jun Young;Baek, Na Yeon;Son, Gi Seok;Ahn, So Yeon;Yeo, In Uk;Woo, Sang Ah;Yoo, Sung Yun;Lee, Gi Beop;Lim, Soo Beom;Jang, Soo Hyun;Jang, In-Deok;Jeon, Jeong-U;Jeong, Su Jin;Jung, Yeon Ju;Cho, Seong Geon;Cha, Jeong Sik;Hwang, Ki Seok;Lee, Tae-Jun;Lee, Moo-Sik
    • Journal of agricultural medicine and community health
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    • v.44 no.4
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    • pp.165-184
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    • 2019
  • Objectives: The purpose of this study was to identify and compare the difference and related factors with general characteristic and health behaviors, a experience of diagnosis and treatment of chronic diseases between rural and urban among elderly in Korea. Methods: We used the data of Community Health Survey 2017 which were collected by the Korean Center for Disease Control and Prevention. The study population comprised 67,835 elderly peopled aged 65 years or older who participated in the survey. The chi-square test, univariate and multivariate logistic regression analysis were used to analyze data. Results: We identified many significant difference of health behaviors, an experience of diagnosis and treatment with chronic diseases between rural and urban. Compared to urban elderly, the odds ratios (ORs) (95% confidence interval) of rural elderly were 1.136 (1.092-1.183) for diagnosis of diabetes, 1.278 (1.278-1.386) for diagnosis of dyslipidemia, 0.940 (0.904-0.977) for diagnosis of arthritis, 0.785(0.736-0.837) for treatment of arthritis, 1.159 (1.116-1.203) for diagnosis of cataracts, and 1.285(1.200-1.375) for treatment of cataracts. In the experience of diagnosis and treatment of chronic diseases, various variables were derived as contributing factors for each disease. Especially, there were statistically significant difference in the experience of diabetes diagnosis, arthritis diagnosis, cataract diagnosis and dyslipidemia except for hypertension diagnosis (p <0.01) between urban and rural elderly. There were statistically significant differences in the experience of treatment for arthritis and cataract (p <0.01), but there was no significant difference in the experience of treatment for hypertension, diabetes, dyslipidemia between urban and rural elderly. Conclusion: Therefore, it would be necessary to implement a strategic health management project for diseases that showed significant experience of chronic diseases with diagnosis and treatment, reflecting the related factors of the elderly chronic diseases among the urban and rural areas.

Contents of Health Education for Pupils and the Perceptibility after Graduation of Primary School (국민학교(國民學校) 교과서내(敎科書內)의 보건교육내용(保健敎育內容) 및 그 습득도(習得度))

  • Jeon, Bo-Yoon;Kim, Doo-Hie
    • Journal of Preventive Medicine and Public Health
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    • v.18 no.1
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    • pp.99-112
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    • 1985
  • It was measured to check the state of health education by the survey of the items related to the health with the first grade of students in middle school who mastered elementary courses. Totally 50 questions, which were selected from Standard and Dong-A reference books, were given to teachers and have got answered by the students who were totally 959(491 from urban areas and 468 from rural areas). It's done just after they entered middle school for a month, from April 10 to may 10, 1984. There were totally 782 items of health in all subjects of all grades. In contents, the most cases were about mental and emotional health(17.7%), exercise and rest (15.1%), environmental health, health life, personal health care, nutrition and foods, social health and organization, physiology and anatomy, statistics of public health population problem, disease and care, food sanitation, school health, parasitic and communicable disease control, eugenics and heredity(0.4%), etc were followed. In subjects, Korean language had 44.7% of mental and emotional health in 114 cases, arithmetics 46.4% of statistics of public health in 26, sociology, 23.1% of environmental health in 118, natural science, 60.1% of physiology and anatomy in 30, ethics, 40.3% of mental and emotional health in 176, music, 21.8% of mental and emotional health and accidents in 23, art, 42.9% of exercise and rest in 28, physical education, 38.6% of exercise and rest in 201, practical course, 36.2% of nutrition and foods in 61, and there was nothing but only one case in Korean history. Subjects in total cases of health informing items are below: Physical education 25.8, ethics 22.5%, sociology 15.1%, Korean language 14.6%, practical course 7.8%, natural science 3.8%, art 3.6%, arithmetics 3.3%, music 2.9%, Korean history 0.6%. Grades in total cases of health informing items are belows: the sixth grade 29.1%, the fourth grade 21.2%, the fifth grade 18.9%, the third grade 11.6%, the first grade 11.5%, the second grade 7.7%. The sections related to health matters were average 35.4%. According to the grades, the fourth and the sixth grade were 38.2% each other, the highest, and the second grade was 29.3%, the lowest. All scetions in physical education included them. The acceptability to the knowledge for health was belows: 56.3% in urban students and 53.9% in rural students. There was some difference in acceptability between two parties (p<0.005).

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The Ability of Anti-tumor Necrosis Factor Alpha(TNF-${\alpha}$) Antibodies Produced in Sheep Colostrums

  • Yun, Sung-Seob
    • 한국유가공학회:학술대회논문집
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    • 2007.09a
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    • pp.49-58
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    • 2007
  • Inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting abnormal intestinal wall function, even further accelerating the inflammatory process[1]. Despite of the records, etiology and pathogenesis of IBD remain rather unclear. There are many studies over the past couple of years have led to great advanced in understanding the inflammatory bowel disease(IBD) and their underlying pathophysiologic mechanisms. From the current understanding, it is likely that chronic inflammation in IBD is due to aggressive cellular immune responses including increased serum concentrations of different cytokines. Therefore, targeted molecules can be specifically eliminated in their expression directly on the transcriptional level. Interesting therapeutic trials are expected against adhesion molecules and pro-inflammatory cytokines such as TNF-${\alpha}$. The future development of immune therapies in IBD therefore holds great promises for better treatment modalities of IBD but will also open important new insights into a further understanding of inflammation pathophysiology. Treatment of cytokine inhibitors such as Immunex(Enbrel) and J&J/Centocor(Remicade) which are mouse-derived monoclonal antibodies have been shown in several studies to modulate the symptoms of patients, however, theses TNF inhibitors also have an adverse effect immune-related problems and also are costly and must be administered by injection. Because of the eventual development of unwanted side effects, these two products are used in only a select patient population. The present study was performed to elucidate the ability of TNF-${\alpha}$ antibodies produced in sheep colostrums to neutralize TNF-${\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. In vitro study, inhibitory effect of anti-TNF-${\alpha}$ antibody from the sheep was determined by cell bioassay. The antibody from the sheep at 1 in 10,000 dilution was able to completely inhibit TNF-${\alpha}$ activity in the cell bioassay. The antibodies from the same sheep, but different milkings, exhibited some variability in inhibition of TNF-${\alpha}$ activity, but were all greater than the control sample. In vivo study, the degree of inflammation was severe to experiment, despite of the initial pilot trial, main trial 1 was unable to figure out of any effect of antibody to reduce the impact of PAF and LPS. Main rat trial 2 resulted no significant symptoms like characteristic acute diarrhea and weight loss of colitis. This study suggested that colostrums from sheep immunized against TNF-${\alpha}$ significantly inhibited TNF-${\alpha}$ bioactivity in the cell based assay. And the higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent TNF-${\alpha}$ induced intestinal damage in the intact animal. Further study will require to find out an alternative animal model, which is more acceptable to test anti-TNF-${\alpha}$ IgA therapy for reducing the impact of inflammation on gut dysfunction. And subsequent pre-clinical and clinical testing also need generation of more antibody as current supplies are low.

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A Comparative Study of Food Habits and Body Satisfaction of Middle School Students According to Clinical Symptoms (일부 남녀 중학생의 건강 관련 임상증상에 따른 식습관과 체헝관심도에 관한 연구)

  • Sung, Chung-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.2
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    • pp.202-208
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    • 2005
  • This study was conducted to examine the food habits, knowledge of nutrition and actual conditions of food ingestion of adolescent middle school students according to questionnaire answers. Questionnaires were completed by 524 students, divided into a healthy group (n=289) and an unhealthy group (n=235) according to clinical signs. Further questions were asked of the two groups in the areas of food habits, knowledge of nutrition and nutritional attitude. The results were as follows: Mean age of all subjects was 14, heights for male and female students were 162.0 em, and 157.2 cm, weights were 53.4 kg, and 49.4, respectively. Heights and weights of male students were greater than those of female students. The body mass index (BMI) for male and female students was 20.3 kg/$m^2$ and 20.0 kg/$m^2$, respectively, and all data were within normal ranges. There were no significant differences in mean age, height, weight, and BMI between the healthy and unhealthy groups. There was no significant difference in body image recognition between the two groups, although the ratio of dissatisfaction with their own body shape was significantly higher in the female unhealthy group (46.1%), than in the female healthy group (33.0%) (p<0.05). In the area of the struggle to control body weight during the previous year, the female unhealthy group (59.4%) was higher than the female healthy group (38.4%) (p<0.01). There was no significant difference in the scores between the two groups in the areas of knowledge of nutrition and the nutritional attitude. Meal frequency and meal patterns were showed that having breakfast less than 4x/week was significantly higher in the female unhealthy group (44.0%), than in the female healthy group (30.7%) (p<0.01). Meal frequency for suppers<4x/week showed that the female unhealthy group (18.8%) was also higher than the female healthy group (10.7%). Therefore, the unhealthy group exhibited a higher pattern of missing both breakfast and supper. The male unhealthy group (16.7%) dined out more frequently than the male healthy group (12.3%) (p<0.01), and female unhealthy group also indulged in snacking significantly more frequently than the female healthy group. The unhealthy group also ate only 1 item for meals more frequently than the healthy group and no significant difference. The conclusion of this study is that adolescent Korean middle school students, who showed a higher incidence of clinical symptoms, representing an unhealthy status, missed breakfast and supper, and dined out and indulged in snacking more frequently. Their quality of breakfast and satisfaction of body image were also lower than the healthy group. These results indicated that there is a high correlation between a Korean adolescent's health status, food habits and body image satisfaction. It is recommended that a more intense program of nutritional education and monitoring be introduce into the current Korean middle-school system in order to optimally support and maximize the health potential of the current population of Korean student.

Expression of Decidual Natural Killer (NK) Cells in Women of Recurrent Abortion with Increased Peripheral NK Cells (말초혈액자연살해세포가 증가된 반복유산 환자의 탈락막자연살해세포의 발현)

  • Yeon, Myeong-Jin;Yang, Kwang-Moon;Park, Chan-Woo;Song, In-Ok;Kang, Inn-Soo;Hong, Sung-Ran;Cho, Dong-Hee;Cho, Yong-Kyoon
    • Clinical and Experimental Reproductive Medicine
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    • v.35 no.2
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    • pp.119-129
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    • 2008
  • Objective: The purpose of this study was to quantify decidual $CD56^+$ and $CD16^+$ NK cell subtype population and to evaluate the correlation between decidual NK cell expression and peripheral $CD56^+$ NK cell expression in women with a history of recurrent abortion and increased peripheral NK cells. Methods: Twenty-nine women with recurrent abortion and elevated peripheral $CD56^+$ NK cell percentage who had chromosomally normal conceptus were included in this study. Thirty-two women with recurrent abortion who had chromosomally abnormal conceptus were used as controls. Distribution of $CD56^+$ and $CD16^+$ NK cells in decidual tissues including implantation sites was examined by immunohistochemical staining. The degree of immunohistochemical staining was interpreted by score and percentage. Results: There was a significant difference in decidual $CD56^+$ NK cell score ($43.6{\pm}24.5$ vs. $23.9{\pm}16.3$ P =0.001) and $CD56^+$ NK cell percentage ($42.1{\pm}11.7$ vs. $33.9{\pm}15.8$ P =0.027) between increased peripheral NK cell group and control group. However, there was no statistically significant difference in decidual $CD16^+$ NK cell score ($18.7{\pm}9.5$ vs. $13.2{\pm}39.4$ P =0.108) and $CD16^+$ NK cell percentage ($24.7{\pm}5.9$ vs. $23.4{\pm}11.7$ P =0.599). There was no significant correlation between decidual NK cell score and peripheral NK cell percentage in increase peripheral NK cell group (peripheral $CD56^+$ NK cell percentage vs. decidual $CD56^+$ NK cell score, r=-0.016, P =0.932, peripheral $CD16^+$ NK cell percentage vs. decidual $CD16^+$ NK cell score, r=0.008, P =0.968). Conclusion: This study shows that $CD56^+$ decidual NK cells are increased in decidua of women exhibiting a history of recurrent abortion with increased $CD56^+$ peripheral NK cell. There was no significant correlation between decidual and peripheral NK cell increment in increase peripheral NK cell group. This study suggests the possibility that decidual NK cells may play an important role in the immune mechanism of recurrent abortion.