• Title/Summary/Keyword: 2-mass system

Search Result 3,188, Processing Time 0.035 seconds

Epidemiological Studies on Giardia Infection Associated with environmental Pollution (Giardia에 의한 환경오염(環境汚染)과 감염(感染)에 관한 역학적(疫學的) 연구(硏究))

  • Lee, Keun-Tae;Kim, Seok-Chan;Song, Jong-Sool;Chung, Pyung-Rim
    • Journal of agricultural medicine and community health
    • /
    • v.9 no.1
    • /
    • pp.56-66
    • /
    • 1984
  • Giardia lamblia is a pathogenic flagellate causing intestinal disorders such as diarrhea, abdominal pain and malabsorption of nutrients. Giardia is mainly infected by the ingestion of contaminated foods per os. Craun (1979) has recently reported that mass infection of this flagellate through the contaminated water supply systems is one of public health hazards. Also, so-called traveller's diarrhea is sometimes caused by Giardia infection (CDC, U.S.A., 1971). However, a few epidemiological studies figuring out the mode of infection or control measures of Giardia infection has been done so far in Korea. The present study was aimed to know the prevalence of Giardia infection in several Korean populations, detectability of this flagellate in water systems and the viability of the cysts against sewages and disinfectants applying to drinking water. In the present study, 388 stool specimens from orphanage children in Chun-joo, Chung-joo, On-yang and Chun-an areas and 538 stool specimens from inhabitants in Woo-do, In-chon, and Chun-joo were examined by formalin-ether concentration technique to detect out Giardia cysts. On the other hand, water samples from 14 sites of Han River and its tributaries were collected in May through July, 1984. Fifty liter of water sample in each sampling site was then filtered through water filtering system deviced by U.S. Environmental Proutection Agency and the sediments rinsed out from the thread rolls, a part of water filtering system, were examined to detect out the Giardia cysts. In order to observe the viability of Giardia cysts in the sewage samples, the cysts were treated in it at $4^{\circ}C$ or $25^{\circ}C$ for 7 through 28 days. For this purpose, the cysts were also exposed to various concentrations of disinfectants such as chlorine, iodine and ozone gas for proper time intervals. After treatment, the viability test of the Giardia cysts were carried out by method of Rice and Schaefer (1981) with minor modification. The results obtained in this study were as follows : 1) The detection rates of G lamblia cysts in the stool specimens were 18.3% in orphans and 4.3% in general examinees. 2) The prevalences of Giardia Infection were higher in the young age groups than in-adults. The highest positive rate was 18.4% in the age group less than 10. 3) Of 14 water specimens sampled from Han River system and its tributaries around the Seoul area, the Giardia cysts were detected from 4 samples, and no cyst was found in the water supply systems. 4) The cysts treated in the sewage survived for 28 days at $4^{\circ}C$ and for 13 days at $25^{\circ}C$. 5) The cysts were completely destroyed within 60 minutes by exposure to 8 mg/l of residual chlorine at 4g and within 30 minutes by exposure to the same concentration of chlorine at $25^{\circ}C$. 6) The cysts were all dead when exposed to 1 mg/1 of iodine for 60 minutes at $4^{\circ}C$ or $25^{\circ}C$. 7) The cysts were destroyed after 10 minute exposure in 0.15 mg to 0.25mg of residual ozone gas per liter. Summarizing the above results, it is considered that Giardia infection is regarded as water-borne disease and the cysts are able to be controlled by the application with the disinfectants in the water supply systems.

  • PDF

Efficacy of a Protective Grass Shield in Reduction of Radiation Exposure Dose During Interventional Radiology (방사선학적 중재적 시술시 납유리의 방사선 방어효과에 관한 연구)

  • Jang, Young-Ill;Song, Jong-Nam;Kim, Young-Jae
    • Journal of the Korean Society of Radiology
    • /
    • v.5 no.5
    • /
    • pp.303-308
    • /
    • 2011
  • Background/Aims : The increasing use of diagnostic and therapeutic interventional radiology calls for greater consideration of radiation exposure risk to radiologist and radiological technician, and emphasizes the proper system of radiation protection. This study was designed to assess the effect of a protective grass shield. Methods : A protective grass was following data depth, 0.8 cm; width, 100 cm; length, 100 cm, lead equivalent, 1.6 mmPb. The protective shield was located between the patient and the radiologist. Thirty patients (13 male and 17 female) undergoing interventional radiology between September 2010 and December 2010 were selected for this study. The dose of radiation exposure was recorded with or without the protective grass shield at the level of the head, chest, and pelvis. The measurement was made at 50 cm and 150 cm from the radiation source. Results : The mean patient age was 69 years. The mean patient height and weight was $159.7{\pm}6.7$ cm and $60.3{\pm}5.9$ kg, respectively. The mean body mass index (BMI) was $20.5{\pm}3.0$ kg/m2. radiologists received $1530.2{\pm}550.0$ mR/hr without the protective lead shield. At the same distance, radiation exposure was significantly reduced to $50.3{\pm}85.2$ mR/hr with the protective lead shield (p-value<0.0001). The radiation exposure to radiologist and radiological technician was significantly reduced by the use of a protective lead shield (p value <0.0001). The amount of radiation exposure during interventional radiology was related to the patient' BMI (r=0.749, p=0.001). Conclusions : This protective shield grass is effective in protecting radiologist and radiological technician from radiation exposure.

Microenvironments and Cellular Proliferation Affected by Oxygen Concentration in Non-Small Cell Lung Cancer Cell Line (비소세포폐암주에서 산소 농도에 따른 미세 배양 환경과 세포 증식능)

  • Shin, Jong Wook;Jeon, Eun Ju;Kwak, Hee Won;Song, Ju Han;Lee, Young Woo;Jeong, Jae Woo;Choi, Jae Cheol;Kim, Jae-Yeol;Park, In Won;Choi, Byoung Whui
    • Tuberculosis and Respiratory Diseases
    • /
    • v.63 no.3
    • /
    • pp.242-250
    • /
    • 2007
  • Background: Abnormal angiogenesis can induce hypoxia within a highly proliferating tumor mass, and these hypoxic conditions can in turn create clinical problems, such as resistance to chemotherapy. However, the mechanism by which hypoxia induces these changes has not yet been determined. Therefore, this study was conducted to determine how hypoxia induces changes in cell viability and extracellular microenvironments in an in vitro culture system using non-small cell lung cancer cells. Methods: The non-small cell lung cancer cell line, A549 was cultured in DMEM or RPMI-1640 media that contained fetal bovine serum. A decrease in the oxygen tension of the media that contained the culture was then induced in a hypoxia microchamber using a $CO_2-N_2$ gas mixture. A gas analysis and an MTT assay were then conducted. Results: (1) The decrease in oxygen tension was checked the anaerobic gas mixture for 30 min and then reoxygenation was induced by adding a 5% $CO_2-room$ air gas mixture to the chamber. (2) Purging with the anaerobic gas mixture was found to decrease the further oxygen tension of cell culture media. (3) The low oxygen tension resulted in a low pH, lactic acidosis and a decreased glucose concentration in the media. (4) The decrease in glucose concentration that was observed as a result of hypoxia was markedly different when different types of media were evaluated. (5) The decrease in oxygen tension inhibited proliferation of A549 cells. Conclusion: These data suggests that tumor hypoxia is associated with acidosis and hypoglycemia, which have been implicated in the development of resistance to chemotherapy and radiotherapy.

North Korea's Nuclear Strategy: Its Type Characteristics and Prospects (북한 핵전략의 유형적 특징과 전망)

  • Kim, Kang-nyeong
    • Korea and Global Affairs
    • /
    • v.1 no.2
    • /
    • pp.171-208
    • /
    • 2017
  • This paper is to analyze the type characteristics and prospects of the North Korean nuclear strategy. To this end, the paper is composed of 5 chapters titled introduction; the concept and type of nuclear strategy; the nuclear capabilities of North Korea and the declarative nuclear strategy; the operational characteristics and prospects of the North Korean nuclear strategy; and conclusion. Recently, the deployment of nuclear weapons and the enhancement of nuclear capabilities in North Korea have raised serious problems in our security and military preparedness. Nuclear strategy means military strategy related to the organization, deployment and operation of nuclear weapons. The study of North Korea's nuclear strategy begins with a very realistic assumption that the nuclear arsenal of North Korea has been substantiated. It is a measure based on North Korea's nuclear arsenal that our defense authorities present the concepts of preemptive attack, missile defense, and mass retaliation as countermeasures against the North Korean nuclear issue and are in the process of introducing and deploying them. The declared nuclear declaration strategy of the DPRK is summarized as: (1)Nuclear deterrence and retaliation strategy under the (North Korea's) Nuclear Weapons Act, (2)Nuclear preemptive aggression, (3)The principle of 'no first use' of nuclear weapons in the 7th Congress. And the intentions and operational characteristics of the North Korean nuclear strategy are as follows: (1)Avoiding blame through imitation of existing nuclear state practices, (2)Favoring of nuclear strategy through declarative nuclear strategy, (3)Non-settlement of nuclear strategy due to gap between nuclear capability and nuclear posture. North Korea has declared itself a nuclear-weapon state through the revised Constitution(2012.7), the Line of 'Construction of the Nuclear Armed Forces and the Economy'(2013.3), and the Nuclear Weapons Act(2013.4). However, the status of "nuclear nations" can only be granted by the NPT, which is already a closed system. Realistically, a robust ROK-US alliance and close US-ROK cooperation are crucial to curbing and overcoming the North Korean nuclear threat we face. On this basis, it is essential not only to deter North Korea's nuclear attacks, but also to establish and implement our own short-term, middle-term and long-term political and military countermeasures for North Korea's denuclearization and disarmament.

Comparison of Health Status and Nutrient Intakes of Elders Who Participated in MOW and Free Congregate Meal Services (가정배달급식과 무료 회합급식 이용 노인의 건강 및 영양섭취상태 비교)

  • Chung, Eun-Jung;Shim, Eu-Gene
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.36 no.11
    • /
    • pp.1399-1408
    • /
    • 2007
  • This study was conducted to compare health and nutritional status of 45 home-living elderly people receiving free Meals on Wheels (MOW) (13 men, 32 women) and 81 low income class elderly people receiving free congregate meals (CM) (10 men, 71 women) served in Seoul. Data were obtained from questionnaires, anthropometry and interviews for the 24-hour dietary recall methods. There were no significant differences between the two groups in age and body mass index. Education level, type of housing, family type and income of the two groups also were not significantly different. In MOW, frequencies of exercise were lower while the prevalence of stroke, respiratory disease and loneliness were higher, compared with the CM. The scores of ADL, IADL and food habit of MOW were lower than those of CM. The average daily nutritional intake of both MOW and CM were as a whole under the DRI for Koreans. Energy and macro-nutrient intakes of MOW were tended to be lower than CM (except protein intakes for female). Ca, K, vitamin A, vitamin $B_1$, vitamin $B_2$, vitamin C and folate intakes of MOW were less than 50% of DRI. Percentages of subjects consuming energy less than 75% of EER and 4 nutrients intakes less than EAR were higher in MOW (42.2%) than in CM (1.2%). Our results indicated that dietary nutritional status of MOW was very poor, especially in the case of female elderly groups. For the welfare of the home-living elderly people receiving free MOW, meal service programs should be improved in quality of diet by national supports.

A Study on the Behavior of Surface-Applied Urea with $^{15}N$ Isotope Dilution Technique in Paddy Soil (논토양에서 중질소(N-15)를 이용한 표면시용 요소로부터 유래하는 질소의 행동에 관한 연구)

  • Lee, Sang-Mo;Yoo, Sun-Ho
    • Applied Biological Chemistry
    • /
    • v.37 no.4
    • /
    • pp.277-286
    • /
    • 1994
  • The pot experiment using $^{15}N$ isotope dilution technique was carried out to calculate the balance of nitrogen of surface applied urea in the rice-soil system. The $^{15}N$ concentration was determined by stable isotope ratio mass spcetrometer (model: VG ISO-GAS MM622). In the pots with $^{15}N$ labeled urea application at the rates of 15 and 30 kg N/10a, the percentage of nitrogen derived from fertilizer (NDFF) in rice was higher at the rate of 30 kg N/10a (average 89%) than at the rate of 15 kg N/10a (average 64%). However, the recovery as percentage of fertilizer N by rice was higher at the rate of 15 kg N/10a (65.5%) than at the rate of 30 kg N/10a (54.2%). The percentage of the fertilizer N remained in extractable inorganic N form at the rates of 15 and 30 kg N/10a were $13.5%\;(NH_4-N\;5.53%,\;NO_3-N\;7.99%)$ and $16.5%\;(NH_4-N\;7.49%,\;NO_3-N\;8.98%)$ in unplanted soil, and $2.0%\;(NH_4-N\;0.63%,\;NO_3-N\;1.32%)$ and$2.3%\;(NH_4-N\;0.87%,\;NO_3-N\;1.40%)$ in soil planted to rice, respectively. The dominant form of inorganic-N in soil after harvest was $NO_3-N$ form rather than $NH_4-N$ form regardless of urea application rate or rice cultivation. The percentage of the fertilizer N remained in organic N form at the rates of 15 and 30 kg N/10a were 65.0 and 41.8% in unplanted soil, and 23.7 and 26.9% in soil planted to rice, respectively. In conclusion, the efficiency of surface-applied urea was greater at the rate 15 kg N/10a than at the rate of 30 kg N/10a.

  • PDF

A Need Assessment on Establishment of Oriental Health Promotion Center (한방건강증진센터 설립에 대한 인식 및 요구조사)

  • Lee, Hyang-Yeon;Kim, Kwuy-Bun;Cho, Kyoul-Ja;Shin, Hye-Sook;Kim, Kwang-Joo;Moon, Heui-Ja;Park, Shin-Ae;Kim, Yoon-Hee;Kang, Hyun-Sook
    • Journal of East-West Nursing Research
    • /
    • v.5 no.1
    • /
    • pp.90-101
    • /
    • 2000
  • The study attempts to examine the degree of cognition and demand on health promotion center of oriental nursing. It puts unique nursing intervention using traditional health promotion connected with oriental medicine to practical use for residents' health promotion and prevention of disease. With the study design of cross-sectional descriptive study, 516 residents who live in 26 Dongs, Dongdaemoon-gu were selected. The tool of study consists of 30 questions which the study team made for the degree of cognition and demand on health promotion center of oriental nursing. Cronbach's $\alpha$ in the degree of cognition was .8028. Collection of research data had been done from October 1 to October 30, 1999 with help of Dongdaemoon-gu office after pretest from 20 residents. Collected data were analyzed into the number and percentage in the characteristic of a subject and connected with demand on the establishment of center, the mean and the standard deviation in the degree of cognition and F-tests in the difference of the degree of cognition by characteristics. The results were as follow; 1) The characteristic of subject of this study was male 50.6%, and average age was 38.5 years old and 30-39 years old occupied the highest percentage with 31.6%. The married were 71.8%, over high school graduates was 85.6%, monthly income from 500 thousand won to 2 million won was 86.1%. 50.8% was the type living with parents, children and sibling. 2) When they were sick, the institution which residents used at first was a pharmacy(69.2%) and hospital(27.5%), but oriental medicine hospital was just 1.4%. As for subjective health condition, 82.5% answered over average, and 28.7% answered that they had chronic illness such as arthritis, chronic digestion problem, hypertension and so on. As for information collection on health, mass communication(34.9%) and medically concerned people(28.1%) occupied relatively high rate. Free health diagnosis system(36.8%) and establishment of health promotion center(31.5%) among welfare programs that residents want to enjoy were high ranked. The rate using a special institution for health was 17.8%, and among these institutions, the rate using aerobic exercises, health center(7.0%) and steamed room(5.4%) was high. Besides, other institutions such as breathing at the abdomen, finger-pressure therapy, meridian massage, foot massage, and so on were being used. 3) As the average of the degree of cognition on health promotion center of oriental medicine was 2.92, the degree of cognition was medium. The description, "health promotion center of oriental medicine is necessary for health keeping of healthy people, including people who have a problem in health" showed the highest degree of cognition(3.04, ${\pm}0.64$). 4) As for the intention on using health promotion center of oriental nursing, 61.4% said "yes", "no" was just 1.4%. The services that people relatively high wanted to be served from the center were measures reducing stress(68.0%) (relaxation therapy, meditation, breathing at the abdomen and so on), acupuncture(66.5%), finger-pressure(61.6%), moxibustion(57.6%), meridian massage(44.2%), postpartum care(40.3%) and so on. 5) As for the degree of cognition on the establishment of health promotion center of oriental nursing by characteristics of subject, there was significant difference(F=4.03, p=.046) between male(3.01) and female(2.91). But there was no significant difference by age, marital status, level of educational achievement and monthly income. As the above result, cognition on the establishment of health promotion center of oriental nursing was relatively low because people were not familiar with about the health promotion center of oriental nursing yet. However once the center will be established, the degree of demand on the center will be relatively high. So positive advertisement will be necessary, and the management of useful programs will be also required in order to make people recognize the advantage when they actually will use the center. On the other hand, as the subject of the study consists of many young people of below 30, the health problem came to be low. And in the case of sampling, the study using random sampling that can represent population will be required.

  • PDF

In vitro Multiplication of Hosta Tratt. Species Native to Korea by Shoot-tip Culture (경정배양에 의한 한국 자생 비비추속 식물의 기내증식)

  • Choi, Han;Yang, Jong Cheol;Ryu, Sun Hee;Yoon, Sae Mi;Kim, Sang Yong;Lee, Seung Youn
    • Korean Journal of Plant Resources
    • /
    • v.32 no.1
    • /
    • pp.53-62
    • /
    • 2019
  • The purpose of this study was to establish the in vitro propagation system by shoot tip culture of six Hosta species native to Korea (Hosta capitata (Koidz.) Nakai, H. clausa Nakai, H. jonesii M.G.Chung, H. minor (Baker) Nakai, H. venusta F.Maek., and H. yingeri S.B.Jones) for mass proliferation and a new cultivar development. The shoot tips of each Hosta species were cultured on MS medium containing eight combinations of 0.5, 1.0, 2.0, 4.0 mg/L BA with 0.1 mg/L NAA, 0.1, 0.5, 1.0, 2.0 mg/L TDZ with 0.1 mg/L NAA, and without any PGRs (control). They were investigated on callus, somatic embryo, crown bud, differentiation and growth of shoot and root, total fresh weight after 8 weeks of culture. In all six Hosta species, callus and somatic embryo induction rate and multiple shooting rate of the PGRs treatment group were higher than that of the control group. The highest number of differentiated shoots were obtained on medium supplemented with 2.0 ㎎/L TDZ in H. capitata (5.4), 1.0 mg/L TDZ in H. clausa and H. jonesii (3.3 and 5.8, respectively), 0.5 mg/L BA in H. minor (11.1), 1.0 mg/L BA and 0.1 mg/L TDZ in H. venusta (8.1), and 0.5 mg/L TDZ in H. yingeri (9.8). In somatic embryo formation, the PGRs treatment group of H. jonesii and H. yingeri were more effective than the control group, and the effects were relatively less in H. capitata, H. clausa Nakai, H. minor, H. venusta. Crown bud formation of four Hosta species (H.capitata, H. clausa, H. jonesiig, and H. yingeri) were also higher in the PGRs treatment group than in the control group. Crown bud formation of four Hosta species (H.capitata, H. clausa, H. jonesiig, and H. yingeri) were also higher in the PGRs treatment group than in the control group. H. clausa showed no significant effect on callus and shoot differentiation regardless of the type and concentration of cytokinin, but slightly increased in formation of crown bud in TDZ.

First report of Telenomus remus Nixon(Scelionidae), an egg parasitoid of Spodoptera frugiperda(J.E. Smith)(Noctuidae) in Korea and its biological characteristics (한국에서 열대거세미나방 알기생벌 Telenomus remus Nixon (가칭: 밤나방검정알벌)[검정알벌과]의 첫 보고 및 생물적 특성 연구)

  • Jum Rae Cho;Bo Yoon Seo;June Yeol Choi;Gwan Seok Lee;Meeja Seo;Jeong Hwan Kim
    • Korean Journal of Environmental Biology
    • /
    • v.40 no.2
    • /
    • pp.187-198
    • /
    • 2022
  • In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3rd to 4th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.

Prevalence and Risk Factors of Gallstones in Adult Health Screening Population (건강한 성인의 담석 유병률과 위험인자)

  • Lee, Mi-Hwa;Kwon, Duck-Moon;Cho, Pyong-Kon
    • Journal of radiological science and technology
    • /
    • v.37 no.4
    • /
    • pp.287-294
    • /
    • 2014
  • Gallstone is the most common disease of the biliary system. Korean has experienced an increase in the percentage of cholesterol gallstones. The major risk factors associated with cholesterol gallstones are age, gender as well as obesity. This study was designed to determine the prevalence of gallstones in the last three years and evaluate the associated risk factors in the population who underwent health screening. The study population consisted of 2,484 males and 2,212 females who visited the health promotion center in Dalseogu, Daegu in Korea from January 2011 to December 2013. Each participant in the study had their biliary system gallbladder examined using ultrasonography. Classified as underweight, normal weight or overweight using the population of obese according to the body mass index, and classified according to mood diagnosis of diabetes presented by the American Diabetes Association. Fasting blood glucose and number of liver function, the divided the control group by referring to the normal liver function values used herein. The geological map, I was classified as NCEP APT III. A showed of total 148 people were found to have gallstones. The prevalence of sex among 148 patients (3.15%) 84 men (1.79%) and 64 women 1.36%) which shows significantly there is little difference. 1.84% 40 years and below, 3.38% 40's showed age prevalence was 4.66% in 50's and above. In addition, Total-cholesterol was at the most in 52 people, LDL-cholesterol in 398 people, Triglyceride in 36 people, HDL-cholesterol in 19 people. The abnormal group, was created from the total-cholesterol categories from a physical examination of a subject that has been found to be gallstones in the gallbladder. A result of conducting the univariate analysis shows the prevalence of gallstones, a correlation that is meaningful. The logistic regression analysis of multiple ages was chosen to show risk factors age independent cholelithiasis. In spite of the conclusion, gallstones are not displayed in relation to the metabolic syndrome but in order to clarify this, not only the subject of a health examination is needed but, a further study of the general public when possible.