• 한국산림과학회지
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• 제109권3호
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• pp.259-270
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• 2020

최근 20년 동안 고온, 건조 등 이상기상 현상이 빈발해지면서 병해충으로 인한 피해가 아닌 생리적 스트레스로 인한 소나무 피해 사례가 지속적으로 보고되고 있다. 2014년도에는 울진 소광리 산림유전자원보호구역 내에 금강소나무(Pinus densiflora for. erecta Uyeki)의 집단고사가 발견되어 이에 대한 원인 구명과 산림관리방안 마련이 요구되었다. 이에 본 연구는 2008~2015년 항공사진에서 발견된 울진 소광리 금강소나무 고사 피해 발생 지역의 지형 및 임분 특성을 파악하여 고사 발생의 영향 요인을 도출하고 이를 기반으로 전체 지역의 고사피해 발생 위험지역을 예측하는 것을 목표로 하였다. 소나무 고사발생 지점 정보와 해발고도, 경사 등의 지형정보, 영급, 경급 등의 임분 정보 등 총 14개의 설명변수를 이용하여 고사발생 예측모델을 구축하였다. 모형 개발에는 Decision Tree, Random Forest (RF), Support Vector Machine (SVM) 등 기계학습 기법을 적용하였으며, RF와 SVM가 정확도 93% 이상으로 좋은 성능을 보였다. 소나무 고사와 관련된 주요 변수 분석 결과, 소나무 고사의 지형적인 취약지역은 해발고도가 높은 동시에 일사량이 높으며 수분 조건이 불리한 지역이었으며, 임분 특성 중에서는 특히 5~15m 높이의 수직적 임분밀도가 높은 소나무림, 그리고 영급이 높은 소나무림에서 고사 위험성이 높다고 평가되었다. RF와 SVM 모형 예측에 따라, 소나무 고사위험도가 높은 지역의 면적은 연구대상지 전체 소나무림 면적의 약 9.5%, 115ha로 평가되었다. 본 연구의 고사위험도 평가 결과는 금강소나무 취약지역의 현황을 조사하고 아직 피해가 발생하지 않은 취약지역에 대한 적극적인 기후변화 적응 산림관리를 수행하기 위한 기반자료로 활용될 수 있다.

• 동의생리병리학회지
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• 제20권4호
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• pp.766-783
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• 2006

This study describes philosophical background regarding '虛' in oriental medicine in an effort to understand the relationships among some of the Eastern philosophy in accordance with differentiated meanings in several resources by analyzing examples of '虛' in Huang Di Nei Jing. The various usages of '虛' used in Huang Di Nei Jing are as follows: naming; condition of pulse; emptiness; '太虛' which was referred universal space by Chinese ; insufficiency, lack or scarcity, deficiency ; and the description of vitality, mental faculties. 外丹修煉(training by external substances) had the attitude do that withdraw the death by taking external materials. The meaning of '虛'in 外丹修煉 is similar to that in oriental medicine in terms of deficiency. That is, both 外丹修煉 and the oriental medicine consider that the death and disease are caused by the deficiency of something. However, there also exists difference between 外丹修煉 and the oriental medicine. 外丹修煉 supplements through withdrawal prohibition due to the characteristic of unchangeability and stern or immortal while oriental medicine provides concrete object of deficiency. 精(essence of life), 氣(ki, functional activity), and fe(vitality) not only have been considered as basic component of human body, but they also have been an important subject of health preservation for longevity with health in Taoism and oriental medicine. In oriental medicine, 精 and 氣 have been perceived as physical basis of human body and 神 as controller. 內丹修煉(Training of internal active substances) 掠nds to return to '虛', the early state of life through individual training, and attempts to withdraw death through continuous recurrence. The oriental medicine and 內丹修煉 held great value of 神 among health preservation of 精, 氣, and 神. They seek theoretical basis from philosophical Taoism. However, '虛' in Taoism is different from that in training by internal substances and oriental medicine: '虛' in philosophical Taoism has metaphysical concept which refers overcome of life and death, but '虛' in 內丹修煉 and oriental medicine have empirical concept. '太虛' is considered as formless space where it is emp Dut filled with 氣. It is conceptualized with the premise of the relevant adaptation of human body to natural environment theory referring that the interaction between the heaven and the earth makes changes; all creation is originated , and human is affected by the interaction of the heaven and the earth. Furthermore, in $\ulcorner$運氣七篇$\lrcorner$ (Seven chapters described about the five circuit phases and the six atmospheric influences), the expression that the earth is in the center of '太虛' and huge amount of 氣 supports it proves that $\ulcorner$運氣七篇$\lrcorner$ adapts '渾天設'(Chaotic universe thee). In Taoism, '虛' is the grounds where all creation is generated in the optimal condition of Tao. As regards the aspect of mentality, it is the condition in which one can free from the dualistic concepts such as right and wrong, beauty and ugliness, life and death, and so on. Although the ultimate goal of oriental medicine, the achievement of longevity without sickness, might contrast with the Taoist belief that perceives life and death as the natural phenomena or the flowing of the 氣, and eliminates all international, the idea of Taoism that one should live substantial life with naivety, and make Harmony with the nature might be influential to the oriental medicine.

• 한국해양학회지:바다
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• 제11권4호
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• pp.158-164
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• 2006

2000년 12월부터 담수를 시작한 용담호는 총 저수량 8.2억톤으로 국내 5위의 대규모 다목적댐 호수로서, 새만금 담수호에 유입되는 하천수의 최상류에 위치한 인공호이다. 새만금 방조제가 완공되어 수문을 조작하면, 용담호의 계절적인 식물플랑크톤 군집변화는 신생 새만금호의 녹조현상을 좌우하는 한 요인이 될 것이다. 용담호의 초기 담수화 과정 중 2002-2003년 하계에 남세균 녹조현상이 나타났으며, 녹조현상을 일으킨 주요 속은 Anabaena, Microcystis, Aphanizomenon 등이었다. 이 가운데 사상체 남세균인 Anabaena속에는 영양세포 이외에 이질세포나 휴면세포 등의 특수기능 세포를 가진 종들이 포함되어 있다. 용담호 녹조현상이 나타난 현장의 시료에서 분리한 Anabaena spiroides v. crassa의 단종배양체인 KNU-YD0310종주를 확립하였으며, 실내배양 실험을 통하여 이 종주의 영양염 요구를 연구하였다. 질소영양염 제한 조건에서는 이질세포의 영양세포에 대한 비율이 높았으며, 질소제한 정도에 따라 그 비율은 더욱 증가하였다. 질소고정능이 있는 KNU-YD0310는 질소제한 조건에서도 성장이 지속되나, 인의 경우에는 초기의 공급 농도에 비례하는 성장을 나타내었다. 인영양염 제한 조건에서는 휴면세포의 형성량이 증가하여, 인 제한의 경우에는 실험 종주가 세포대사를 억제하여 부적합한 환경조건에서의 생존기간을 연장시키는 적응전략을 가진 것으로 판단된다. 이와 같은 Anabaena spiroides v. crassa의 생리 생태적 특성은 향후 새만금 담수호의 녹조현상 예방대책 수립을 위한 수서생태학적 기준으로 활용될 수 있을 것이다.

• The Korean Journal of Physiology
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• 제1권1호
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• pp.103-120
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• 1967

As pointed out by many previous investigators, the cardio-pulmonary system of well trained athletes is so adapted that they can perform a given physical exercise more efficiently as compared to non-trained persons. However, the time course of the development of these cardio-pulmonary adaptations has not been extensively studied in the past. Although the development of these training effects is undoubtedly related to the magnitude of an exercise load which is repeatedly given, it would be practical if one could maintain a good physical fitness with a minimal daily exercise. Hence, the present investigation was undertaken to study the time course of the development of cardio-pulmonary adaptations while a group of non-athletes was subjected to a daily 6 to 10 minutes running exercise for a period of 4 weeks. Six healthy male medical students (22 to 24 years old) were randomly selected as experimental subjects, and were equally divided into two groups (A and B). Both groups were subjected to the same daily running exercise (approximately 1,000 kg-m). 6 days a week for 4 weeks, but the rate of exercise was such that the group A ran on treadmill with 8.6% grade for 10 min daily at a speed of 127 m/min while the group B ran for 6 min at a speed of 200 m/min. In order to assess the effects of these physical trainings on the cardio-pulmonary system, the minute volume, the $O_2$ consumption, the $CO_2$ output and the heart rate were determined weekly while the subject was engaged in a given running exercise on treadmill (8.6% grade and 127 m/min) for a period of 5 min. In addition, the arterial blood pressure, the cardiac output, the acid-base state of arterial blood and the gas composition of arterial blood were also determined every other week in 4 subjects (2 from each group) while they were engaged in exercise on a bicycle ergometer at a rate of approximately 900 kg m/min until exhaustion. The maximal work capacity was also determined by asking the subject to engage in exercise on treadmill and ergometer until exhaustion. For the measurement of minute volume, the expired gas was collected in a Douglas bag. The $O_2$ consumption and the $CO_2$ output were subsequently computed by analysing the expired gas with a Scholander micro gas analyzer. The heart rate was calculated from the R-R interval of ECG tracings recorded by an Offner RS Dynograph. A 19 gauge Cournand needle was inserted into a brachial artery, through which arterial blood samples were taken. A Statham $P_{23}AA$ pressure transducer and a PR-7 Research Recorder were used for recording instantaneous arterial pressure. The cardiac output was measured by indicator (Cardiogreen) dilution method. The results may be summarized as follows: (1) The maximal running time on treadmill increased linearly during the 4 week training period at the end of which it increased by 2.8 to 4.6 times. In general, an increase in the maximal running time was greater when the speed was fixed at a level at which the subject was trained. The mammal exercise time on bicycle ergometer also increased linearly during the training period. (2) In carrying out a given running exercise on treadmill (8.6%grade, 127 m/min), the following changes in cardio·pulmonary functions were observed during the training period: (a) The minute volume as well as the $O_2$ consumption during steady state exercise tended to decrease progressively and showed significant reductions after 3 weeks of training. (b) The $CO_2$ production during steady state exercise showed a significant reduction within 1 week of training. (c) The heart rate during steady state exercise tended to decrease progressively and showed a significant reduction after 2 weeks of training. The reduction of heart rate following a given exercise tended to become faster by training and showed a significant change after 3 weeks. Although the resting heart rate also tended to decrease by training, no significant change was observed. (3) In rallying out a given exercise (900 kg-m/min) on a bicycle ergometer, the following change in cardio-vascular functions were observed during the training period: (3) The systolic blood pressure during steady state exercise was not affected while the diastolic blood Pressure was significantly lowered after 4 weeks of training. The resting diastolic pressure was also significantly lowered by the end of 4 weeks. (b) The cardiac output and the stroke volume during steady state exercise increased maximally within 2 weeks of training. However, the resting cardiac output was not altered while the resting stroke volume tended to increase somewhat by training. (c) The total peripheral resistance during steady state exercise was greatly lowered within 2 weeks of training. The mean circulation time during exorcise was also considerably shortened while the left heart work output during exercise increased significantly within 2 weeks. However, these functions_at rest were not altered by training. (d) Although both pH, $P_{co2}\;and\;(HCO_3-)$ of arterial plasma decreased during exercise, the magnitude of reductions became less by training. On the other hand, the $O_2$ content of arterial blood decreased during exercise before training while it tended to increase slightly after training. There was no significant alteration in these values at rest. These results indicate that cardio-pulmonary adaptations to physical training can be acquired by subjecting non-athletes to brief daily exercise routine for certain period of time. Although the time of appearance of various adaptive phenomena is not identical, it may be stated that one has to engage in daily exercise routine for at least 2 weeks for the development of significant adaptive changes.