32 research outputs found

    Seasonal changes of pigment contents in Cornus alba bark and the influence of environmental factors

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    학위논문 (석사) -- 서울대학교 대학원 : 농업생명과학대학 산림과학부(산림환경학전공), 2021. 2. 김현석.흰말채나무는 밝은 붉은 색상의 수피가 감상가치가 있어 겨울용 조경수로 널리 활용되는 관목이다. 가을철 계절의 변화에 따른 흰말채나무 수피의 색상 변화는 식물체 내적 요인과 환경 요인의 영향을 받는다. 본 연구는 겨울용 조경수로서 흰말채나무의 적절한 재배 환경 조건을 찾기 위해, 실제 재배 장소에서 토양 습도, 상대습도, 토양 산도 등 환경 요인이 흰말채나무 수피의 색상발현에 미치는 영향에 대해 조사하였다. 2020년 8월부터 10월까지 흰말채나무 수피에 엽록소, 카로티노이드, 안토시아닌의 함량 변화를 모니터링 하였다. 가을에서 겨울로 기온이 낮아짐에 따라 흰말채나무 수피에 총 엽록소와 카로티노이드 함량은 점진적으로 감소하였고 안토시아닌 함량은 점진적으로 증가하였고 색상은 초록색에서 붉은색으로 바뀌었다. 잎과 열매 등에서 밝혀진 가을철 색소의 생화학적 변화가 수피에서도 유사하게 일어났다. 안토시아닌 합성은 토양 습도와 상대습도에 따른 건조 스트레스의 영향을 받았다. 건조 스트레스 조건에서 안토시아닌 합성이 촉진되는 현상이 가을철 흰말채나무 수피에서도 확인되었다. 안토시아닌 성분을 분석해본 결과 총 3종류의 안토시아닌이 검출되었는데 cyanidin이 가장 많았고 delphinidin과 peonidin도 소량 존재하였다. 또한 안토시아닌의 색상 발현에 영향을 미치는 것으로 알려진 토양 산도 역시 흰말채나무 수피의 색상발현에 영향을 미치는 것으로 판단되었다. 아울러 겨울용 조경수로서 흰말채나무의 수피 색상 발현의 위한 환경 조건을 찾기 위해서는 색상 기호도 조사 등을 통한 흰말채나무 수피 색상에 대한 평가와 환경 인자들의 복합적인 영향에 대한 연구가 필요할 것으로 사료된다.Cornus alba L. is an ornamental shrub widely used especially for winter landscaping with its noteworthy bright-red colored stem. Its bark coloration seasonally changes as a sign of autumn senescence and is affected by internal and environmental factors. To find out the proper cultural conditions as a high-value landscape shrub for the cold and low season, this field case research focused on the effect of environmental factors, including soil moisture, relative humidity, and soil pH, on the coloration of C. alba bark during autumnal senescence. These environmental factors are thought dominantly to affect the winter bark coloration in C. alba. In this study, the seasonal changes of chlorophylls, carotenoids, and anthocyanins in the bark of C. alba from August 2020 to October 2020 were monitored. The total amounts of chlorophylls and carotenoids decreased gradually. Anthocyanins accumulated as influenced by soil moisture and relative humidity which cause drought stress. During autumn senescence, the fact that anthocyanin contents increase under drought stress conditions was verified in the bark as well, which is normally observed in leaves and fruits. Three anthocyanins were detected from the bark of C. alba. The major one was found to be cyanidin and the others were delphinidin and peonidin. The minor pigments are usually known to have existed in small quantities in this plant. Additionally, as a well-known affecting factor for anthocyanin color expression, soil pH might affect the bark coloration. To suggest ideal growing conditions for the effective coloration of cornus, further researches on the winter bark color considering the effect of the other environmental factors like light, temperature, and so on and reflecting on peoples preference as a landscape element should be performed.제1장 서 론 1 1.1.연구 배경 1 1.2.연구 목적 4 제2장 연 구 사 5 2.1.단풍 5 2.2.안토시아닌 6 2.3.흰말채나무 8 제3장 재료 및 방법 10 3.1.연구 대상지 및 재료 10 3.1.1.대상지 10 3.1.2.재료 11 3.2.환경 12 3.2.1.토양 습도, 상대습도, 온도 12 3.2.2.토양 산도 12 3.3.색소 함량 변화 조사 12 3.3.1.엽록소 및 카로티노이드 함량 12 3.3.2.총 안토시아닌 함량 12 3.3.3.안토시아닌 성분 14 3.4.통계 분석 14 제4장 결 과 15 4.1.환경 15 4.1.1.토양 습도 변화 15 4.1.2.상대습도 변화 16 4.1.3.온도 변화 17 4.1.4.토양 산도 19 4.2.엽록소 및 카로티노이드 함량 19 4.2.1.CLP에서의 총 엽록소 및 카로티노이드 함량 변화 19 4.2.2.PG에서의 총 엽록소 및 카로티노이드 함량 변화 20 4.3.총 안토시아닌 함량 22 4.3.1.CLP에서의 총 안토시아닌 함량 변화 22 4.3.2.PG에서의 총 안토시아닌 함량 변화 23 4.4.안토시아닌 성분 23 4.4.1.CLP에서의 안토시아닌 성분 변화 23 4.4.2.PG에서의 안토시아닌 성분 변화 25 제5장 고 찰 27 5.1.흰말채나무 수피 단풍과 색소함량의 변화 27 5.2.토양 습도와 건조 스트레스가 흰말채나무 수피에 안토시아닌 생성에 미치는 영향 28 5.2.1.토양 습도 및 건조 스트레스의 영향 28 5.2.2.상대습도의 영향 30 5.3.안토시아닌 성분 변화와 흰말채나무 수피 색상 발현 30 5.3.1.안토시아닌 성분 변화 30 5.3.2.안토시아닌 성분 변화가 색상 발현에 미치는 영향 31 5.4.토양 산도가 흰말채나무 수피 색상 발현에 미치는 영향 31 5.5.야간 기온과 흰말채나무 수피에 안토시아닌 생성 33 5.6.겨울용 조경수로서 흰말채나무의 수피 색상 발현을 위한 환경 조건 34 제6장 결 론 36 인용 문헌 37Maste

    Wingspan Stenting for Symptomatic Severe In-Stent Stenosis of a Closed-Cell Stent after Stent-Assisted Coiling of a Ruptured Intracranial Aneurysm

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    We report the 3-year follow-up result of Wingspan intracranial stenting for symptomatic severe in-stent stenosis after stent-assisted coiling (SAC) for a ruptured left distal internal carotid artery (ICA) aneurysm. A middle-aged male patient visited our hospital for in-stent stenosis of a stent that was placed to treat a ruptured ICA aneurysm. Routine follow-up cerebral angiography, 1 year after SAC, showed in-stent stenosis around the distal markers of the inserted stent at the left M1 proximal segment. Six months later, he developed right dysesthesia. We performed intracranial stenting with Wingspan stent for the in-stent stenosis. Follow-up digital subtraction angiography performed 1 year after the Wingspan stenting showed good patency of the ICA and middle cerebral artery flow without evidence of restenosis. At 3-year follow-up, magnetic resonance angiography showed sufficient middle cerebral artery flow although the stenting segment could not be visualized clearly. Wingspan stenting might be a feasible option in patients with iatrogenic intracranial stenosis resulting from in-stent stenosis who experience the progression of intracranial stenosis with manifestation of neurological symptoms despite dual anti-platelet therapy.ope

    Association between longitudinal blood pressure and prognosis after treatment of cerebral aneurysm: A nationwide population-based cohort study

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    Background: High blood pressure is a major risk factor for the development and rupture of cerebral aneurysm. Endovascular coil embolization and surgical clipping are established procedures to treat cerebral aneurysm. However, longitudinal data of blood pressure after the treatment of cerebral aneurysm and its impact on long-term prognosis are not well known. Methods: This retrospective cohort study included 1275 patients who underwent endovascular coil embolization (n = 558) or surgical clipping (n = 717) of cerebral aneurysm in 2002-2015 using the nationwide health screening database of Korea. Systolic and diastolic blood pressure of patients were repeatedly obtained from the nationwide health screening program. We performed a multivariate time-dependent Cox regression analysis of the primary composite outcome of stroke, myocardial infarction, and all-cause death. Results: During the mean follow-up period of 6.13 ± 3.41 years, 89 patients suffered the primary outcome. Among the total 3546 times of blood pressure measurement, uncontrolled high blood pressure (systolic ≥140 mmHg or diastolic ≥90 mmHg) was 22.9%. There was a significantly increased risk of primary outcome with high systolic (adjusted HR [95% CI] per 10 mmHg, 1.16 [1.01-1.35]) and diastolic (adjusted HR [95% CI] per 10 mmHg, 1.32 [1.06-1.64]) blood pressure. Conclusions: High blood pressure is prevalent even in patients who received treatment for cerebral aneurysm, which is significantly associated with poor outcome. Strict control of high blood pressure may further improve the prognosis of patients with cerebral aneurysm.ope

    Anterior Cervical Discectomy and Fusion Alters Whole-Spine Sagittal Alignment

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    PURPOSE: Anterior cervical discectomy and fusion (ACDF) has become a common spine procedure, however, there have been no previous studies on whole spine alignment changes after cervical fusion. Our purpose in this study was to determine whole spine sagittal alignment and pelvic alignment changes after ACDF. MATERIALS AND METHODS: Forty-eight patients who had undergone ACDF from January 2011 to December 2012 were enrolled in this study. Cervical lordosis, thoracic kyphosis, lumbar lordosis, sagittal vertical axis (SVA), and pelvic parameters were measured preoperatively and at 1, 3, 6, and 12 months postoperatively. Clinical outcomes were assessed using Visual Analog Scale (VAS) scores and Neck Disability Index (NDI) values. RESULTS: Forty-eight patients were grouped according to operative method (cage only, cage & plate), operative level (upper level: C3/4 & C4/5; lower level: C5/6 & C6/7), and cervical lordosis (high lordosis, low lordosis). All patients experienced significant improvements in VAS scores and NDI values after surgery. Among the radiologic parameters, pelvic tilt increased and sacral slope decreased at 12 months postoperatively. Only the high cervical lordosis group showed significantly-decreased cervical lordosis and a shortened SVA postoperatively. Correlation tests revealed that cervical lordosis was significantly correlated with SVA and that SVA was significantly correlated with pelvic tilt and sacral slope. CONCLUSION: ACDF affects whole spine sagittal alignment, especially in patients with high cervical lordosis. In these patients, alteration of cervical lordosis to a normal angle shortened the SVA and resulted in reciprocal changes in pelvic tilt and sacral slope.ope

    韓國의 政府主導 共同硏究開發의 成果에 대한 硏究

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    Thesis (doctoral)--서울대학교 대학원 :경영학과 경영학 전공 ,2003.Docto

    국가간 반도체 산업의 발전경로에 관한 비교 연구 : 미국, 일본 및 한국을 중심으로

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    학위논문(석사)--서울大學校 大學院 :經營學科 經營學專攻,1997.Maste

    Lower risk of subarachnoid haemorrhage in diabetes: a nationwide population-based cohort study

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    Background and purpose: Diabetes mellitus (DM) is a common metabolic disorder with increased risk of cardiovascular and cerebrovascular complications. However, its relationship with risk of subarachnoid haemorrhage (SAH), the most devastating form of stroke, remains controversial. Methods: To evaluate the relationship between DM and risk of SAH, we performed a retrospective cohort study using a nationwide, population-based, health screening database in Korea. We included participants without history of stroke who underwent a nationwide health screening programme between 2003 and 2004. Primary outcome was occurrence of SAH. Participants were followed up until development of SAH or December 2015. Multivariate Cox proportional hazards regression analysis was performed with adjustments for age, sex, systolic blood pressure, total cholesterol, body mass index, physical activity, smoking status, alcohol habit, household income and treatment with antihypertensive agents and statins. Results: Among 421 768 study participants, prevalence of DM was 9.6%. During a mean follow-up period of 11.6±1.9 years, 1039 patients developed SAH. Presence of DM was significantly associated with decreased risk of SAH (adjusted HR 0.68; 95% CI 0.53 to 0.86; p<0.001). Elevated level of fasting blood glucose was also negatively associated with risk of SAH (adjusted HR per 1 mmol/L increase 0.90; 95% CI 0.86 to 0.95; p<0.001). Conclusion: DM and elevated level of fasting blood glucose were inversely associated with risk of SAH. Further studies may elucidate the possibly protective, pathophysiological role played by hyperglycaemia in patients at risk of SAH.ope

    실시간 운영체제의 태스크 실행 시간 모니터링 장치 및 그 방법

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    본 발명은 실시간 운영체제의 태스크 실행 시간 모니터링 장치 및 그 방법에 관한 것이다.본 발명에 따르면, 실시간 운영체제의 태스크 실행 시간 모니터링 장치를 이용한 실시간 운영체제의 태스크 실행 시간 모니터링 방법에 있어서, 태스크 실행 시간 모니터링 방법은 복수의 태스크의 시작 시점의 시작 시간과 종료 시점의 종료 시간을 측정하는 단계, 상기 측정된 시작 시간 및 종료시간을 각각의 태스크 별로 저장하는 단계, 그리고 사용자 단말로부터 상기 시작 시간 및 종료 시간에 대한 정보 송신을 요청하는 정보 출력 메시지를 수신하면, 상기 정보 출력 메시지를 수신한 시점 이전에 저장된 시작 시간 및 종료 시간에 대한 정보를 사용자 단말로 출력하는 단계를 포함한다.이와 같이 본 발명에 따르면, 사용자로부터 태스크의 모니터링 정보 요청이 있는 경우에만 기 저장된 시작 시간 및 종료 시간을 일괄 제공하게 되므로, 각 태스크가 종료될 때마다 시작 시간 및 종료 시간을 사용자에게 제공하는 종래의 기술에 비해 정보 출력에 따른 시스템의 부하를 크게 줄일 수 있다
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