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Variation in Harmful Algal Blooms in Korean coastal waters since 1970 (1970년대 이후 한국 연안의 적조 발생 변화)

  • Lim, Weol-Ae;Go, Woo-Jin;Kim, Kyoung-Yeon;Park, Jong-Woo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.5
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    • pp.523-530
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    • 2020
  • Based on the results of harmful algal blooms (HABs) monitoring by the National Institute of Fisheries Science and local governments, the effects of changes in the marine environment on HABs are described. Since the beginning of HABs monitoring in 1972, they continued to increase from the 1980s to the 1990s. After the largest number of HAB incidents (109) in 1998; the trend declined until the 2010s. Most HABs in the 1970s were caused by diatoms. In the 1980s, coastal dinoflagellates caused HABs; Cochlodinium polykrikoides blooms have been occurring continuously since 1993. There are three HAB species that cause damage to fisheries in Korea. The high-density bloom of Karenia mikimotoi caused mass mortality in shellfish in Jinhae Bay in 1981. Karenia sp. blooms occurring around Tongyeong in 1992 killed aquaculture fish. Since the occurrence of the largest fisheries damage of KRW 76.6 billion in 1995 caused by C. polykrikoides blooms, they have been occurring continuously. The concentration of nutrients in coastal waters was the highest in the 1980s and has declined since the mid-1990s. This reduction in nutrient concentration is a good explanation for the decreasing number of HABs. Since 2016, a summer high water temperature of 30℃ or more has appeared, and the range and scale of C. polykrikoides blooms have been greatly reduced. In 2016, K. mikimotoi blooms occurred around Wando, Jangheung and Goheung and small scale blooms of C. polykrikoides occurred around Yeosu. There were no C. polykrikoides blooms in 2017; however, Alexandrium affine blooms occurred from Yeosu to Tongyeong. There was a small-scale blooms of C. polykrikoides in 2018 compared to those in the previous years. Our results show that reduction in nutrients and the high water temperature owing to climate change are a good explanation for variation in HABs in Korean coastal waters.

A Survey on the Knowledge and Attitudes of Women in Taegu toward Weaning Diet for Infants (이유식에 대한 대구지역 여성들의 인식조사)

  • Kim, Kyung-Ah;Lee, Eun-Sil;Lee, Young-Hwan;Shin, Son-Moon;Choi, Kwang-Hae
    • Journal of Yeungnam Medical Science
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    • v.14 no.2
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    • pp.370-382
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    • 1997
  • Successful weaning is very important to provide adequate nutrients for normal growth and to induce a good diet habit. We conducted a survey on the knowledge and attitudes of women who live in Taegu toward weaning in infants, to figure out how much they know about weaning diet for the infants, which source they prefer to get the information about weaning diet, whether their knowledge affect their practice about weaning in infants, and the most effective way to educate them. A survey was conducted with the prepared questionnaire on women who responded at the residential area and market place, and those who visited Department of Pediatrics, Yeungnam University Hospital from July 25 to September 15, 1997. Statistical analysis was done with student t-test and ANOVA using SPSS program. Among total 303 responders, those who aged between 30 and 39 years were 37.2%. Scores for the six questions about weaning policy showed highest in the age group between 30 and 39 years. Higher score was recorded in the more educated group, in those who get informations about weaning diet from books, magazines and pediatricians. The majority of the responders had wrong concepts, such as feeding weaning diet using bottle(69.1%), feeding mixed with formula in the same bottle(64.5%), addition of salt(68.4%). Those who had higher educational level preferred books, magazines rather than neighbors or mother to get informations about weaning diet. Those who preferred books or magazines started weaning, stopped bottle feeding, and used spoon earlier, and their children had unbalanced diet habits less frequently. Home-made food was used most frequently, and commercial products were used less frequently. Those who were employed preferred home-made food rather than commercial products, it may be caused by the difference of the educational backgrounds from those of the unemployed. In conclusion, most responders ask neighbors and mother to get informations about weaning, and the incorrect knowledge from them could cause inadequate weaning practice and induce bad diet habit in their children. We have to find the reasons why they did not refer books or magazines frequently, and the way to resolve the problem.

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Separation of Nanomaterials Using Flow Field-Flow Fractionation (흐름 장-흐름 분획기를 이용한 나노물질의 분리)

  • Kim, Sung-Hee;Lee, Woo-Chun;Kim, Soon-Oh;Na, So-Young;Kim, Hyun-A;Lee, Byung-Tae;Lee, Byoung-Cheun;Eom, Ig-Chun
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.11
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    • pp.835-860
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    • 2013
  • Recently, the consumption of nanomaterials has been significantly increased in both industrial and commercial sectors, as a result of steady advancement in the nano-technologies. This ubiquitous use of nanomaterials has brought up the concern that their exposure to environments may cause detrimental effects on human health as well as natural ecosystems, and it is required to characterize their behavior in various environmental media and to evaluate their ecotoxicity. For the sake of accomplishing those assessments, the development of methods to effectively separate them from diverse media and to quantify their properties should be requisitely accompanied. Among a number of separation techniques developed so far, this study focuses on Field-Flow Fractionation (FFF) because of its strengths, such as relatively less disturbance of samples and simple pretreatment, and we review overseas and domestic literatures on the separation of nanomaterials using the FFF technique. In particular, researches with Flow Field-Flow Fractionation (FlFFF) are highlighted due to its most frequent application among FFF techniques. The basic principle of the FlFFF is briefly introduced and the studies conducted so far are classified and scrutinized based on the sort of target nanomaterials for the purpose of furnishing practical data and information for the researchers struggling in this field. The literature review suggests that the operational conditions, such as pretreatment, selection of membrane and carrier solution, and rate (velocity) of each flow, should be optimized in order to effectively separate them from various matrices using the FFF technique. Moreover, it seems to be a prerequisite to couple or hyphenate with several detectors and analyzers for quantification of their properties after their separation using the FFF. However, its application has been restricted regarding the types of target nanomaterials and environmental media. Furthermore, domestic literature data on both separation and characterization of nanomaterials are extremely limited. Taking into account the overwhelmingly increasing consumption of nanomaterials, the efforts for the area seem to be greatly urgent.

Clninical Features of Rotaviral Gastroenteritis in Neonates (신생아에서 로타바이러스 위장관염의 임상양상에 대한 고찰)

  • Park, Shin-I;Kwon, Hae Oak;Lee, Jun Ho;Jung, Su Jin
    • Clinical and Experimental Pediatrics
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    • v.48 no.10
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    • pp.1121-1125
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    • 2005
  • Purpose : Rotavirus is the main cause of infantile diarrheal disease worldwide, especially in patients 3-24 months of age. Infants younger than 3 months of age are relatively protected by transplacental antibody. So the purpose of this study is to evaluate the clinical features and severity of neonatal rotaviral gastroenteritis less than 1 month of age. Methods : A retrospective chart review was established of 62 neonates less than 1 month of age and with a diagnosis of rotaviral gastroenteritis who had been admitted to Pochon CHA University between June 2002 through July 2004. The rotavirus was examined by stool latex agglutination. Results : During 2 years, the total number of admitted patients for rotaviral gastroenteritis was 688 and among these, less than 1 month of age accounted for 9%(62). The occurrence was generally even distribution from January to July($7.14{\pm}1.0$) but since then decreased($2.4{\pm}1.8$). The most common chief complaint was mild fever(46%) when admitted which subsided within 1 hospital day in most patients. 4 patients had seizure and cyanosis with no typical symptoms of rotaviral gastroenteritis. During admission, all the patients had diarrhea. 17% of the patients had leukocytosis and positive C-reactive protein. In one patient, stool occult blood test was positive but there was no necrotizing gastroenteritis evidence. The mean period of hospital day was $5.8{\pm}2.5$ and breast-milk feeding was 62.9%. Conclusion : Neonatal rotaviral gastroenteritis is not a rare disease. Most patients have fever and diarrhea and improve through conservative therapy but a few patients may have severe complications so we must be more cautious about the hygiene for prevention.

Selection of Fungicide Against Lichen-forming Fungi for the Chemical Control of Lichen Colonization on Stone Heritages and Plants (석조문화재 및 식물 착생 지의류의 화학적 방제를 위한 살균제 선발)

  • Kim, Jung-A;Jung, Min-Hae;Jeon, Hae-Sook;Koh, Young-Jin;Hur, Jae-Seoun
    • The Korean Journal of Pesticide Science
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    • v.14 no.3
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    • pp.261-265
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    • 2010
  • Lichens, a symbiotic organism of fungi and algae, cause serious damage to national heritages of stone master piece and costly trees for gardening. The present study was conducted to screen effective fungicides against lichen-forming fungi to control the biological agents deteriorating stone heritages and trees. Five commercial fungicides (Fenarimol EC, Etridiazole EC, Iminoctadinetriacetate SL, Difenoconazole+lminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC) were tested against the lichen-forming fungi (LFF) isolated from seven saxicolous (Caloplaca sp., Ramalina sp., Xanthoparmelia sp., and Xanthoria sp.,) or corticolous (Parmelia sp.,) lichen species. Preliminary screening test showed that no LFF could grow on the MY (malt-yeast extract) agar medium amended with the recommended concentrations of each fungicide. Further screening was conducted at 1%, 10% and 20% of the recommended concentrations of the fungicides. After 7 week incubation at $15^{\circ}C$ in the dark, Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC completely inhibited the fungal growth of all the tested LFF, even at 1% of the concentration. Two fungicides of Fenarimol EC and Iminoctadinetriacetate SL exhibited a moderate inhibition activity at the lower concentrations. Etridiazole EC was less effective in the fungal growth inhibition than the other four fungicides. The results suggested that lichens colonizing on precious stone heritages and trees can be eradicated by applying Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC even 1% of the recommended concentrations. Selected fungicide application at such a low concentration will facilitate the chemical use to prevent and preserve stone heritages from biological deterioration induced by lichens and the allied microbes.

A STUDY ON 4 TYPE CONSTITUTION AND SIFE CHARACTER OF OBESE PATIENTS (비만인의 생활특성과 사상체질에 관한 연구)

  • KIM, DAL RAE
    • Journal of Sasang Constitutional Medicine
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    • v.9 no.1
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    • pp.303-313
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    • 1997
  • Disease depends on the three factors, agent, host and environment. According to history of disease, by early 1900s the case of deaths is infectious disease, in late 1900s care of infectious diseases and tremendous scale of chronic disease, i.e., heart disease, diabetes, cancers and etc, makes care of chronic diseases be a most important theme. Now, life-style of diet is being westernized and in high industry-oriented society, obesity makes attack fate remarkably increase and life-expectancy become short, so that it causes severe problem of health. Chronic disease, such as obesity, is not affected by specific agent, but depends of interaction between host and environmental factors. There is the theory of constitutional medicine in Korean Medicine. According to it, all the people have constitutional specificity and disease. Because obesity is a kind of disease, there is the corresponding constituent being apt to be fat. Oriental Medicine utilizes herb-medication, acupuncture, and massage-therapy in treating obesity. Therefore study on relationship between constituent and obesity for OPD patients of Sangji-Oriental Medicine Hospital is carried out. The results are summarized as followings. 1. 70.2% of obesity patients are Taeumin(太陰人), 26.9% of those are Soyangin(少陽人), 2.9% of thoese are Soeumin(少陰人). 2. Most cases, high value of Free Fat Acid and Triglyceride not that of Total Cholesterol and Low Density Lipoprptein is meaningful in obesity patient blood. The corelationship between lipid test and Constitution is meaningful in Triglyceride and Free Fatty Acid. 3. Obesity is not related with gene. 4. Obesity is not related with Boyak(Herb-Med : 補藥). 5. Obesity mostly happens after delivery, contraception and operation. 6. Obese Patients are apt to eat between meals, especially food of wheat flour such as a snack. 7. The aim of treating obesity is not persuit of beauty but of keeping healthy. 8. 2.2Kg of body weight is lost after 4 week-treatment. 9. Common cause of obesity is overeating of carbohydrate and lipid than meat.

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Minimized Priming Volume for Open Heart Surgery in Neonates and Infants (신생아와 유아 심장 수술 시 심폐기회로 충진액의 최소화)

  • Kim, Woong-Han;Chang, Hyoung-Woo;Yang, Sung-Won;Cho, Jae-Hee;Lee, Kyung-Hoon;Baek, In-Hyuk;Kwak, Jae-Gun;Park, Chun-Soo;Lee, Jeong-Ryul;Kim, Yong-Jin
    • Journal of Chest Surgery
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    • v.42 no.4
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    • pp.418-425
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    • 2009
  • Background: Cardiopulmonary bypass (CPB) involves use of an initial priming volume which can cause side effects such as hemodilution, transfusion, inflammatory reaction and edema. Hence, there have been efforts made tore-duce the initial priming volume. We compared this traditional method to a CPB method that uses a minimized priming volume (MPV). Material and Method: For 97 patients who underwent congenital cardiac surgery between July 2007 to June 2008, we discussed each case and decided which method to use. We reviewed the medical records and cardiopulmonary bypass sheets of the patients. Result: We used a MPV method for 46 patients, and a traditional method for the other 51. There were no significant differences in preoperative and intraoperative characteristics between the two groups, such as body weight, age, cardiopulmonary bypass time, lowest body temperature, etc. However, the priming volume was much smaller in the MPV group than the traditional group (p<0.001). The volume of initially mixed packed RBC was also much smaller in the MPV group (p<0.001). There were no significant differences in postoperative mortality and neurologic complications. Conclusion: We could significantly reduce the initial priming volume and initially mixed pRBC volume with the revised CPB method. We suggest that this method be used more widely for congenital cardiac surgery.

Effects of Stressful Life Events on Patients with Recurrent Ahthous Ulcer. (SRRS를 이용한 재발성 아프타성 구내궤양 환자의 생활변화에 관한 연구)

  • Ko, Myung-Yun;Kim, Young-Ae;Ok, Soo-Min;Heo, Jun-Young;Jeong, Sung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.37 no.4
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    • pp.195-203
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    • 2012
  • Recurrent aphthous ulcer(RAU) is the most frequent form of oral ulceration with a prevalence in the general population ranging between 5% and 60%. The peak age of onset is between 10 and 19 years of age, and it can persist into adulthood and throughout the patient's lifespan, with no gender predilection. The disease is characterized clinically into three types: minor aphthous ulcer, major aphthous ulcer and herpeticform ulcers. The cause of RAU is unknown and thought to be multifactorial with many triggers or precipitating factors that include familial tendency or genetic predisposition, allergy, medications, hormones, stress or anxiety, and immunologic abnormalities. The need for consideration of psychological factors in the pathogenesis of oral disease has been increasingly acknowledged over the last decades and many studies have highlighted the psycho-social impact of oral conditions. In this study, we tried to evaluate the influence of emotional stress in RAU. There were thirty patients with a clinical diagnosis of RAU and other subjects who did not show any signs of systemic disorders include RAU. They are evaluated by using modified Holmes and Rahe's Social Readjustment Rating Scale (SRRS). As a result, a significantly higher level of stress was found in the RAU patients than the control group. Therefore it can be concluded that psychological stressors play an important role in the RAU.

Fault reactivation potential during $CO_2$ injection in the Gippsland Basin, Australia (호주 Gippsland Basin에서 $CO_2$ 주입 중 단층 재활성화의 가능성)

  • Ruth, Peter J. van;Nelson, Emma J.;Hillis, Richard R.
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.50-59
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    • 2006
  • The risk of fault reactivation in the Gippsland Basin was calculated using the FAST (Fault Analysis Seal Technology) technique, which determines fault reactivation risk by estimating the increase in pore pressure required to cause reactivation within the present-day stress field. The stress regime in the Gippsland Basin is on the boundary between strike-slip and reverse faulting: maximum horizontal stress $({\sim}\;40.5\;Mpa/km)$ > vertical stress (21 Mpa/km) ${\sim}$ minimum horizontal stress (20 MPa/km). Pore pressure is hydrostatic above the Campanian Volcanics of the Golden Beach Subgroup. The NW-SE maximum horizontal stress orientation $(139^{\circ}N)$ determined herein is broadly consistent with previous estimates, and verifies a NW-SE maximum horizontal stress orientation in the Gippsland Basin. Fault reactivation risk in the Gippsland Basin was calculated using two fault strength scenarios; cohesionless faults $(C=0;{\mu}=0.65)$ and healed faults $(C=5.4;\;{\mu}=0.78)$. The orientations of faults with relatively high and relatively low reactivation potential are almost identical for healed and cohesionless fault strength scenarios. High-angle faults striking NE-SW are unlikely to reactivate in the current stress regime. High-angle faults oriented SSE-NNW and ENE-WSW have the highest fault reactivation risk. Additionally, low-angle faults (thrust faults) striking NE-SW have a relatively high risk of reactivation. The highest reactivation risk for optimally oriented faults corresponds to an estimated pore pressure increase (Delta-P) of 3.8 MPa $({\sim}548\;psi)$ for cohesionless faults and 15.6 MPa $({\sim}2262\;psi)$ for healed faults. The absolute values of pore pressure increase obtained from fault reactivation analysis presented in this paper are subject to large errors because of uncertainties in the geomechanical model (in situ stress and rock strength data). In particular, the maximum horizontal stress magnitude and fault strength data are poorly constrained. Therefore, fault reactivation analysis cannot be used to directly measure the maximum allowable pore pressure increase within a reservoir. We argue that fault reactivation analysis of this type can only be used for assessing the relative risk of fault reactivation and not to determine the maximum allowable pore pressure increase a fault can withstand prior to reactivation.

Theoretical Study on Optimal Conditions for Absorbent Regeneration in CO2 Absorption Process (이산화탄소 흡수 공정에서 흡수액 최적 재생 조건에 대한 이론적 고찰)

  • Park, Sungyoul
    • Korean Chemical Engineering Research
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    • v.50 no.6
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    • pp.1002-1007
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    • 2012
  • The considerable portion of energy demand has been satisfied by the combustion of fossil fuel and the consequent $CO_2$ emission was considered as a main cause of global warming. As a technology option for $CO_2$ emission mitigation, absorption process has been used in $CO_2$ capture from large scale emission sources. To set up optimal operating parameters in $CO_2$ absorption and solvent regeneration units are important for the better performance of the whole $CO_2$ absorption plant. Optimal operating parameters are usually selected through a lot of actual operation data. However theoretical approach are also useful because the arbitrary change of process parameters often limited for the stability of process operation. In this paper, a theoretical approach based on vapor-liquid equilibrium was proposed to estimate optimal operating conditions of $CO_2$ absorption process. Two $CO_2$ absorption processes using 12 wt% aqueous $NH_3$ solution and 20 wt% aqueous MEA solution were investigated in this theoretical estimation of optimal operating conditions. The results showed that $CO_2$ loading of rich absorbent should be kept below 0.4 in case of 12 wt% aqueous $NH_3$ solution for $CO_2$ absorption but there was no limitation of $CO_2$ loading in case of 20 wt% aqueous MEA solution for $CO_2$ absorption. The optimal regeneration temperature was determined by theoretical approach based on $CO_2$ loadings of rich and lean absorbent, which determined to satisfy the amount of absorbed $CO_2$. The amount of heating medium at optimal regeneration temperature is also determined to meet the difference of $CO_2$ loading between rich and lean absorbent. It could be confirmed that the theoretical approach, which accurately estimate the optimal regeneration conditions of lab scale $CO_2$ absorption using 12 wt% aqueous $NH_3$ solution could estimate those of 20 wt% aqueous MEA solution and could be used for the design and operation of $CO_2$ absorption process using chemical absorbent.