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Preoperative Risk Factors for the Prognosis of Mitral Regurgitation in Patients with Coronary Artery Stenosis and Mitral Regurgitation Who Underwent Coronary Artery Bypass Surgery Alone (승모판폐쇄부전증을 동반한 관상동맥협착증 환자에서 시행한 단독 관상동맥우회술 후 승모판폐쇄부전증의 예후에 영향을 미치는 수술 전 요인)

  • Jin, Ung;Park, Chan-Beom;Choi, Si-Young;Kim, Chi-Kyung
    • Journal of Chest Surgery
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    • v.37 no.5
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    • pp.410-415
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    • 2004
  • Background: In the operation for coronary artery stenosis, the procedures for mitral regurgitation are restricted to cases of more than moderate mitral regurgitation or for the lesions in leaflets. This is based on the belief that the less than mild regurgitation are a form of reversible change results from ischemia with coronary artery stenosis. We studied the changes and prognostic factors of mitral regurgitation in patients with coronary artery stenosis and mitral regurgitation who underwent coronary artery bypass surgery alone. Material and Method: We reviewed the medical records of 90 patients with coronary artery stenosis and mitral regurgitation who underwent coronary artery bypass surgery alone by a single surgeon from Jan. 1995 to Dec. 2002, We grouped the patients according to the postoperative changes of mitral regurgitation, and then we statistically compared the findings of echocardiogram between preoperative and last follow up. Result: There were 24 cases with progression of mitral regurgitation, 12 cases without changes, 54 cases with improvements of mitral regurgitation in total 90 patients. The bypass to LAD was proven as the significant prognostic factor of mitral regurgitation. The preoperative end diastolic left ventricular volume index were higher in aggravated group with 105.38$\pm$38.89 $m\ell$ compared to 71.75$\pm$28,45 $m\ell$ in improvement group, and 84.00$\pm$11.66 $m\ell$ in no change group. The grade of preoperative mitral regurgitation did not show significant differences among the groups. Conclusion: The mitral regurgitation in patient with coronary artery stenosis can be improved after the coronary artery bypass surgery alone. However, the expectation of improvements based on the degree of preparative mitral regurgitation can not be justified, therefore, the procedures for mitral regurgitation should be aggressively considered even in the cases of mild mitral regurgitation. Also, further study should be performed to identify the exact prognostic factors of mitral regurgitation including the left ventricular volume index, and whether the left anterior descending artery has been bypassed.

Acute Renal Failure after On-pump Coronary Artery Bypass Surgery (체외순환하 시행한 관상동맥우회술 후 발생한 급성신부전증)

  • Jin, Ung;Jo, Min-Seop;Park, Chan-Beom;Sa, Young-Jo;Kim, Chi-Kyung
    • Journal of Chest Surgery
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    • v.37 no.5
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    • pp.416-422
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    • 2004
  • Acute renal failure (ARF) is a common postoperative complication after the cardiac surgery. Postoperative ARF have various causes, and are combined with other complications rather than being the only a complication. It deteriorates the general condition of the patient, and makes it difficult to manage the combined complications by disturbing the adequate medication and fluid therapy. We have planned this study to evaluate the effects of postoperative ARF after the on-pump coronary artery bypass surgery (CABG) on the recovery of patients and identify the risk factors. Method and Material: We reviewed the medical records of patients who underwent CABG with cardiopulmonary bypass by a single surgeon from Jan. 2000 to Dec. 2002, We checked the preoperative factors; sex, age, history of previous serum creationism over 2.0 mg/㎗, preoperatively last checked serum creatinine, diabetes, hypertension, left ventricular ejection fraction, intraoperative factors; whether the operation is an emergent case or not, cardiopulmonary bypass time, aortic cross clamp time, the number of distal anastomosis, postoperative factors: IABP. Then we have studied the relations of these factors and the cases of postoperative peak serum creatinine over 2.0 mg/㎗. Result: There were 19 cases with postoperative peak serum creatinine over 2.0 mg/㎗ in a total 97 cases. Dialysis were done in 3 cases for ARF with pulmonary edema and severely reduced urine output. There were 8 cases (42.1%) with combined complications among the 19 patients. This finding showed a significant difference from the 5 cases (6,4%) in the patients whose creatinine level have not increased over 2.0 mg/㎗. The mortalities are different as 1.3% to 10.5%. The risk factors that are related with postoperative serum creatinine increment over 2.0 mg/㎗ are diabetes, the history of previous serum creatinine over 2.0 mg/㎗ and left ventricular ejection fraction. Conclusion: Postoperative ARF after the on-pump CABG is related with preoperative diabetes, the history of previous serum creatinine over 2,0 mg/㎗ and left ventricular ejection fraction. Postoperative ARF could De the reason for increased rate of complications and mortality after on-pump CABG. Therefore, in the patients with these risk factors, the efforts to prevent postoperative ARF like off-pump CABG should be considered.

The Effects of Major Climatic Factors on Barely Response to NPK Fertilizers (대맥(大麥)의 NPK 비료응수(應酬)에 미치는 주요기상인자(主要氣象因子)들의 영향(影響)에 관(關)하여)

  • Park, Nae Jung;Lee, Choon Soo;Ryu, In Soo;Park, Chon Suh;Kim, Yung Sup
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.2
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    • pp.129-136
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    • 1973
  • In order to study the effects of climatic factors on barley responses to NPK fertilizers, the responses under the conditions of cold, moisture and drought damages and in different temperature regions, Nothern, Central, and Southern, which were devided according to average temperature for growing season of barley (from Nov. to May) were investigated from the results of NPK experiments which were carried out from Nov., 1965 to May 1969. The relationships between occurrence rate of cold, moisture, and drought damages and average or average lowest temperature in winter (Dec., Jan., and Feb), and the amount of precipitation in spring (Mar., Apr,. and May) were also investigated. 1. The lower the average lowest temperature, the higher the occurrence rate of cold damage of barley. When affected by cold damage, barley responded more significantly to P and K fertilizers. 2. The more the amount of precipitation in spring, the more the moisture damage and the less the drought damage. Damage from both moisture and drought were the lowest at 280mm. Since the average precipitation in spring in Korea is 230mm, drought damage is always more problem in terms of occurrence of damage, but total yield reduction is greater by moisture damage. 3. When affected by moisture damage, barley responded more to P and K fertilizers. In case of drought damage, only response to K was recognizable. 4. The reductions of barley yield due to cold, moisture, and drought damages were in average 31 (29-33), 42, and 19(12-25)%, respectively. 5. Average barley responses to NPK fertilizers were 44(34-58), 19(5-38), and 9(1-34)%, respectively by percent responses with regard to maximum possible yields. 6. Responses to nitrogen increased as the sunshine hours increased. Under dry condition, the response increased as the precipitation increased. However if the amount of precipitation was excessive or too little, the response was dropped markedly. 7. The responses to P and K were higher in North than South to the same degree. As the average temperature for growing season of barley (from Nov. to May) increased by $1^{\circ}C$, the percent responses to both P and K increased by 4.3%.

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Analysis of Treatment Failures in Early Uterine Cervical Cancer (조기 자궁경부 악성종양의 치료실패에 대한 분석)

  • Kim Joo-Young;Lee Kyu-Chan;Choi Hyung-Sun
    • Radiation Oncology Journal
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    • v.9 no.2
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    • pp.285-291
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    • 1991
  • One hundred and twenty six patients with early uterine cervical cancer who had been treated at Departmen of Radiation Oncology of Korea University Hospital from Jan.1981 to Dec.1988 were analysed retrospectively by the treatment result and pattern of of failures. All patients had stage Ia to IIa disease and were grouped whether they had combination of operation and postop irradiation or radiation therapy alone. 1) Sixty six patients belonged to the combination treatment group and 60 patients to the radiation alone group. 2) Combination group consisted of $18.1\%$(12/66) stage Ia, $71.2\%$(47/66) stage Ib and $10.6\%$ (7/66) stage IIa patients. There were no stage Ia, 18.8$\%$(l1/60) stage Ib and 81.6$\%$(49/60) stage IIa patients for RT alone gronp. 3) There were total 23$\%$(29/126) treatment failures,13 patients in combination group and 16 patients in RT alone group. In 66 patients of combination group, they were found to have 5 locoregional failures, 7 distant failures and 1 at both sites. In 60 patients of RT alone group, 9 locoreginal failure and 7 distant failures occured. Eighty six percent (25/29) of total failures appeared within 18 month after completion of treatment. About 60$\%$ of the patients with regional recurrences which were located at pelvic side wall or pelvic lymph nodes paesented their recurrent disease after 1 year of completion of treatment, whereas same percent of distant failures appeared within 6 month. 5) In RT alone group, the first sites of distant failure were mostly para-aortic lymph node and/or left supraclavicular lymph node (71.4$\%$,5/7). In combination group, various sites such as inguinal lymph node, mediastinal lymph node, liver, lung and bone appeared first or at the same time with para-aortic and supraclavicular lymph node metastasis. 6) Logistic regression analysis was done for multivariate analysis of the factors contributing to locoregional and distant failures. In combination group, adequacy of the resection margin and the presence of positive pelvic node were found to be the most significant factors (p=0.0423 & 0.0060 respectively). In RT alone group, less than complete regression of the tumor at the end of treatment was the only significant contributing factor for the treatment failures (p=0.0013) with good liklihood ratio.

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Evaluation of SWAT Applicability to Simulation of Sediment Behaviois at the Imha-Dam Watershed (임하댐 유역의 유사 거동 모의를 위한 SWAT 모델의 적용성 평가)

  • Park, Younshik;Kim, Jonggun;Park, Joonho;Jeon, Ji-Hong;Choi, Dong Hyuk;Kim, Taedong;Choi, Joongdae;Ahn, Jaehun;Kim, Ki-sung;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.23 no.4
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    • pp.467-473
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    • 2007
  • Although the dominant land use at the Imha-dam watershed is forest areas, soil erosion has been increasing because of intensive agricultural activities performed at the fields located along the stream for easy-access to water supply and relatively favorable topography. In addition, steep topography at the Imha-dam watershed is also contributing increased soil erosion and sediment loads. At the Imha-dam watershed, outflow has increased sharply by the typhoons Rusa and Maemi in 2002, 2003 respectively. In this study, the Soil and Water Assessment Tool (SWAT) model was evaluated for simulation of flow and sediment behaviors with long-term temporal and spatial conditions. The precipitation data from eight precipitation observatories, located at Ilwol, Subi and etc., were used. There was no significant difference in monthly rainfall for 8 locations. However, there was slight differences in rainfall amounts and patterns in 2003 and 2004. The topographical map at 1:5000 scale from the National Geographic Information Institute was used to define watershed boundaries, the detailed soil map at 1:25,000 scale from the National Institute of Highland Agriculture and the land cover data from the Korea Institute of Water and Environment were used to simulate the hydrologic response and soil erosion and sediment behaviors. To evaluate hydrologic component of the SWAT model, calibration was performed for the period from Jan. 2002 to Dec. 2003, and validation for Jan. 2004 to Apr. 2005. The $R^2$ value and El value were 0.93 and 0.90 respectively for calibration period, and the $R^2$ value and El value for validation were 0.73 and 0.68 respectively. The $R^2$ value and El value of sediment yield data with the calibrated parameters was 0.89 and 0.84 respectively. The comparisons with the measured data showed that the SWAT model is applicable to simulate hydrology and sediment behaviors at Imha dam watershed. With proper representation of the Best Management Practices (BM Ps) in the SWAT model, the SWAT can be used for pre-evaluation of the cost-effective and sustainable soil erosion BMPs to solve sediment issues at the Imha-dam watershed. In Korea, the Universal Soil Loss Equation (USLE) has been used to estimate the soil loss for over 30 years. However, there are limitations in the field scale mdel, USLE when applied for watershed. Also, the soil loss changes temporarily and spatially, for example, the Imha-dam watershed. Thus, the SW AT model, capable of simulating hydrologic and soil erosion/sediment behaviors temporarily and spatially at watershed scale, should be used to solve the muddy water issues at the Imha-dam watershed to establish more effective muddy water reduction countermeasure.

The Prognostic Effect of Subpleural Lesions in Early Stage Non-small Cell Lung Cancer - Preliminary Report - (초기 비소세포 폐암 환자의 늑막하 병변이 예후에 미치는 영향; 예비 보고)

  • Lee, Ho-Jun;Lee, Hyung-Sik;Hur, Won-Joo;Lee, Ki-Nam;Choi, Pill-Jo
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.425-431
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    • 1998
  • Purpose : We retrospectively analyzed the impact of subpleural lesions of early stage non-small cell lung cancer on the patterns of failure to support selection of postoperative adjuvant therapy. Methods and Materials : The study included 91 patients who underwent surgery for early stage non-small cell lung cancer at Dong-A University Hospital from Dec 1990 to Sep 1996. Twenty five patients were excluded due to postoperative mortality (four patients, 4.4$\%$) and stage III (21 patients). Of 66 patients, 22 patients were subpleural lesions (15 patients in stage I, and seven patients in stage II). Postoperative adjuvant radiation therapy was given to seven patients with T2Nl disease. The median follow-up duration was 29.5 months (range; 8-84 months). Results : The overall survival rate was 69.5$\%$ at 3 years. For all patients who presented with (22 patients) and without (44 patients) subpleural lesions, 3-year overall survival rates were 35.5$\%$ and 84.6$\%$, respectively (p=0.0017). For stage I patients who presented with (15 patients) and without (29 patients) subpleural lesions, 3-year overall survival rates were 33.1$\%$ and 92.3$\%$, respectively (p=0.001). For stage II patients who presented with (7 patients) and without (15 patients) subpleural lesions, 3-year overall survival rates were 53.3$\%$ and 45.7$\%$, respectively (p=0.911). For patients with T2N0 disease (34 patients) who presented with (11 patients) and without (23 patients) subpleural lesions, 3-year overall survival rates were 27.3$\%$ and 90.3$\%$, respectively (p=0.009). Conclusion : These observations suggest that the subpleural lesion play an important role as a prognostic factor for early stage non-small cell lung cancer. Especially for T2N0 disease, patients with subpleural lesions showed significantly lower survival rate than those without that.

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Clinical Outcome of Multicystic Dysplastic Kidney in 46 Children (다낭성 이형성 신 환아 46명의 예후와 관련한 임상적 고찰)

  • Jeong Il-Cheon;Hwang You-Sik;Ahn Sun-Young;Han Sang-Won;Lee Jae-Seung
    • Childhood Kidney Diseases
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    • v.10 no.1
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    • pp.27-32
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    • 2006
  • Purpose : Conservative management of multicystic dysplastic kidney(MCDK) without nephrectomy has recently been advocated. The purpose of this study was to determine the clinical course of conservatively managed MCDK and to find out possible predictive factors for involution of MCDK by ultrasonography(US). Methods : A retrospective analysis was made on 45 patients(26 boys and 20 girls) in whom MCDK was detected and had been traced by US between Dec. 1993 and Aug. 2005 at Severance Hospital. Results : Median follow-up time was 30 months(range 2-102 months). All patients under-went radionuclide scans and voiding eystourethrograms. The serial follow-up US showed complete involution in 11(24%), partial involution in 19(41%), and no interval change or increased in cyst size in 13(28%) patients. Nephrectomy was done in 3 patients(7%) due to relapsing urinary tract infection(UTI) and severe abdominal distension. The mean age of complete involution of MCDK was 37 months(range 12-84 months). Episodes of UTI were present in 17 patients(37%) and additional genitourinary(GU) abnormalities were found in 22 patients(44%). Hypertension and renal insufficiency was complicated in one patient. No child developed malignant tumor. Univariate analysis showed that five variables were associated with complete involution of the MCDK; gender, site, UTI episode, additional GU abnormalities, and renal length on initial US. After adjusting using the Pearson model, the presence of additional GU abnormalities was exclusively associated with complete involution among the 5 variables(P=0.034). Conclusion : In our review of 46 cases of MCDK, non-surgical approach for patients with MCDK was advisable and we could predict poor prognosis when MCDK is associated with other GU anomalies.

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The Change and Relationship between Maternal Role Strain and Husband's Support in First-time Mothers with regard to their Employment Status (취업유무에 따른 초산모의 배우자 지지와 역할긴장간의 관계 및 변화)

  • Koh, Hyo-Jung
    • Women's Health Nursing
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    • v.4 no.1
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    • pp.5-35
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    • 1998
  • This study attempted to determine the relation between the maternal role strain and their husbands' support in employed and nonemployed first-time mothers, and how it changed over time. A descriptive, longitudinal and comparative study design was conducted to collect and analyzed the data at three times(at 3-4days, at 4-6wks and at 3-month postpartum) regarding the change of maternal role strain and their husbands' support in employed and nonemployed first-time mothers. The subjects were 133 first-time mothers who delivered vaginally at K university hospital in Deagu, Korea from Dec., 1994 to Oct., 1995. Among these 58 were employed and 75 were nonemployed first-time mothers. This instruments used to data collection in this study were by Hobbs(1968 : The Difficulty Index for First-time Parents), Staffensmeier(1982: Transition Difficulty Measure), Tayer(1976: Emotional Support from Husband), Lee, Hae Kyoung(1992 : Physical Support from Husband). The analysis of data was done with SAS/PC program which included percentage, $x^2$-test, Pearson correlation, Repeated Measure ANOVA, Time Contrast Analysis and t-test. The results were as follows : 1. There was a significant negative correlation only at 3-4days(r=-.19, P=.0265) and at 4-6wks postpartum(r=-.18, P=.0392) between maternal role strain and husband's support of the first-time mothers. Thus, the more support from husband, the less maternal role strains the first-time mothers felt. Therefore, the 1st hypothesis that "the more husband's support the first-time mother felt at all the time of testing, the less maternal role strains they got" was partially supported at 3-days and 4-6 weeks postpartum. There was no correlation between maternal role strain and t husband's support of the employed first-time mothers at al testing times(at 3-4days postpartum : r=-.95, P=.9548, at 4-6wks postpartum : r=-.0960, P=.4733 and at 3-month postpartum : r=-.05, P=7306). On the contrary, the unemployed first-time mothers felt less maternal role strain when they received more support from their husband at 3-4 days postpartum(r=-.31, P=.0073) and at 4-6wks postpartum(r=-.23, P=.0490). 2. There was no difference of maternal role strain between two groups with regards to employment status(F=.97, P=.3270). But the maternal role strains of two groups were changed differently each other over time(F=3.89, P=.00234). Therefore, the 2nd hypothesis that "there was the difference in the maternal role strains with regard to employment status and over time" was rejected. 3. There was no difference in husband's support between the employed and the nonemployed first-time mothers(F=3.06, P=.0826). But there was a significant interaction between employment status and over time(F=3.64, P=.0267), so the support from husband of the employed and the unemployed first-time mothers was changed differently each other over time. The support from husband of the employed first-time mothers was lowered significantly and continuously at 4-6wks (F=5.20, P=.0263) and at 3-month postpartum(F=6.47, P=.0137) than at 3-4 days postpartum. On the contrary, there was no difference in change of husband's support of the employed first-time mothers between the 3-4 days and the 4-6wks postpartum(F=1.70, P=.1962) and between the 3-4 days and the 3-month postpartum(F=.21, P=.6513). Mean husband's support of the nonemployed first-time mothers was raised at 4-6wks postpartum than at 3-4 days postpartum but lowed at 3-month postpartum. The support form husband of both groups was tending downwards at 3-month postpartum than at 4-6wks postpartum, but the one between two groups was changed differently each other over time. The husband's support of the employed first-time mothers(M${\pm}$SD=64. 26${\pm}$8.63) was higher than the one of the nonemployed first-time mothers(M${\pm}$SD=59.16${\pm}$11.11) (t=-2.98, P=.0035), so the 3rd hypothesis that "there was the difference in the husband's support with regard to employment status and over time" was supported. On the basis of these conclusions, the following suggestion is proposed. This study examined the change and relationship between maternal role strain and husband's support in the employed and the nonemployed first-time mothers. So the further study regarding the comparison between the employed and the nonemployed multiparas is necessary.

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Prognostic Value of Day 3 Inhibin-B on Assisted Reproductive Technology Outcome (보조 생식술 결과에 있어서 기저혈중 Inhibin-B의 예후인자로서의 유용성)

  • Bai, Sang-Wook;Kim, Jin-Young;Lee, Kyung-Sool;Won, Jong-Gun;Lee, Yong-Joo;Yi, Ji-Won;Chang, Kyung-Hwan;Lee, Byung-Seok;Park, Ki-Hyun;Cho, Dong-Jae;Song, Chan-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.24 no.2
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    • pp.217-223
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    • 1997
  • This study was performed to determine if women with day 3 serum inhibin-B concentrations <45pg/ml (conversion factor to SI unit, 1.00) demonstrate a poor response to ovulation induction and assisted reproductive technology outcome to women with inhibin-B${\ge}45pg$/ml, independant of day 3 FSH, E2 and patient age. From Jan 1996 to Dec 1996, 16 volunteers patients who underwent 25 IVF cycles with luteal phase GnRH agonist suppression and HMG stimulation were allocated to the study group. We evaluated day 3 serum inhibin-B, FSH, E2, peak E2, cancellation rate per initiated cycle (%) and clinical pregnancy rate per initiated cycle (%) according to the above two groups and independent of patient age, day 3 FSH, day 3 E2 and all of above combined. Women with day 3 serum inhibin-B${\ge}45pg$/ml demonstrated higher average day 3 inhibin-B level, clinical pregnancy rate per initiated cycle ($20.3{\pm}2.5$ pg/ml vs $80.9{\pm}5.0$ pg/ml, p<0.05; 24.8% vs 8.5%, p<0.05) and lower day 3 FSH level, cancellation rate per initiated cycle ($6.9{\pm}0.3$ mIU/ml vs $8.5{\pm}0.5$ mIU/ml, p<0.05; 1.5% vs 9.0%, p<0.05). Women with day 3 serum inhibin${\ge}45pg$/ml and age<40 year demonstrated higher pregnancy rate per initiated cycle (28.2% vs 7.4%, p<0.05) and lows. day 3 FSH level, cancellation rate per initiated cycle ($6.9{\pm}0.5$ mIU/ml vs $8.2{\pm}0.7$ mIU/ml, p<0.05; 1.0% vs 9.0%, p<0.05). Women with day 3 serum inhibin${\ge}45pg$/ml and day 3 FSH<15mIU/ml demonstrated higher pregnancy rate per initiated cycle (33.5% vs 9.5%, p<0.05) and lower day 3 FSH level, cancellation rate per initiated cycle ($7.7{\pm}0.2$ mIU/ml vs $8.5{\pm}0.5$ mIU/ml, p<0.05; 1.5% vs 10.0%, p<0.05). Women with day 3 serum inhibin${\ge}45pg$/ml and day 3 E2<50pg/ml demonstrated higher pregnancy rate per initiated cycle (30.0% vs 9.5%, p<0.05) and lower cancellation rate per initiated cycle (1.5% vs 9.5%, p<0.05). Women with day 3 serum inhibin${\ge}45pg$/ml, age<40 year, day 3 FSH<15mIU/ml and day 3 E2<50pg/ml demonstrated higher pregnancy rate per initiated cycle (30.0% vs 10.8%, p<0.05) and lower day 3 FSH level, cancellation rate per initiated cycle ($6.8{\pm}0.6$ mIU/ml vs $8.4{\pm}0.9$ mIU/ml, p<0.05; 1.5% vs 7.8%, p<0.05). Therefore women with low day 3 serum inhibin-B concentrations demonstrate a poorer response to ovulation induction and are less likely to conceive a clinical pregnancy though ART relative to women with high day 3 inhibin-B and day 3 serum inhibin-B, in addition to a day 3 FSH, E2 and patient age, appears helpful in prediction in IVF-ET outcome.

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Gridded Expansion of Forest Flux Observations and Mapping of Daily CO2 Absorption by the Forests in Korea Using Numerical Weather Prediction Data and Satellite Images (국지예보모델과 위성영상을 이용한 극상림 플럭스 관측의 공간연속면 확장 및 우리나라 산림의 일일 탄소흡수능 격자자료 산출)

  • Kim, Gunah;Cho, Jaeil;Kang, Minseok;Lee, Bora;Kim, Eun-Sook;Choi, Chuluong;Lee, Hanlim;Lee, Taeyun;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1449-1463
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    • 2020
  • As recent global warming and climate changes become more serious, the importance of CO2 absorption by forests is increasing to cope with the greenhouse gas issues. According to the UN Framework Convention on Climate Change, it is required to calculate national CO2 absorptions at the local level in a more scientific and rigorous manner. This paper presents the gridded expansion of forest flux observations and mapping of daily CO2 absorption by the forests in Korea using numerical weather prediction data and satellite images. To consider the sensitive daily changes of plant photosynthesis, we built a machine learning model to retrieve the daily RACA (reference amount of CO2 absorption) by referring to the climax forest in Gwangneung and adopted the NIFoS (National Institute of Forest Science) lookup table for the CO2 absorption by forest type and age to produce the daily AACA (actual amount of CO2 absorption) raster data with the spatial variation of the forests in Korea. In the experiment for the 1,095 days between Jan 1, 2013 and Dec 31, 2015, our RACA retrieval model showed high accuracy with a correlation coefficient of 0.948. To achieve the tier 3 daily statistics for AACA, long-term and detailed forest surveying should be combined with the model in the future.