• Korean Journal of Biological Psychiatry
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• v.18 no.2
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• pp.80-89
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• 2011

Pavlovian fear conditioning has been extensively studied for the understanding of neurobiological basis of memory and emotion. Pavlovian fear conditioning is an associative memory which forms when conditioned stimulus (CS) is paired with unconditioned stimulus (US) once or repeatedly. This behavioral model is also important for the understanding of anxiety disorders such as posttraumatic stress disorder. Here we describe the neural circuitry involved in fear conditioning and the molecular mechanisms underlying fear memory formation. During consolidation some memories fade out but other memories become stable and concrete. Emotion plays an important role in determining which memories will survive. Memory becomes unstable and editable again immediately after retrieval. It opens the possibility for us of modulating the established fear memory. It provides us with very efficient tools to improve the efficacy of cognitive-behavior therapy and other exposure-based therapy treating anxiety disorders.

• Korean Journal of Biological Psychiatry
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• v.28 no.2
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• pp.23-35
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• 2021

Fear conditioning and extinction, which are adaptive processes to learn and avoid potential threats, have essential roles in the pathophysiology of anxiety disorders. Experimental fear conditioning and extinction have been used to identify the mechanism of fear and anxiety in humans. However, the brain-based mechanisms of fear conditioning and extinction are yet to be established. In the current review, we summarized the results of neuroimaging studies that examined the brain changes-functional activity and structures-regarding fear conditioning or extinction in healthy individuals. The functional activity of the amygdala, insula, anterior cingulate gyrus, ventromedial prefrontal cortex, and hippocampus changed dynamically with both fear conditioning and extinction. This review may provide an up-to-date summary that may broaden our understanding of pathophysiological mechanisms of anxiety disorder. In addition, the brain regions that are involved in the fear conditioning and extinction may be considered as potential treatment targets in the future studies.

• Korean Journal of Biological Psychiatry
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• v.15 no.4
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• pp.254-264
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• 2008

Objectives : The neural substrate of fear is thought to be highly conserved among species including human. The purpose of this review was to address the neural substrates of fear based on recent findings obtained from animal and human studies. Methods : Recent studies on brain regions related to fear, particularly fear conditioning in rodents and humans, were extensively reviewed. Results : This paper suggests high consistency in anatomical structure and physiological mechanisms for fear perception, response, learning and modulation in animals and humans. Conclusions : Fear is manifested and modulated by well conserved neural circuits among species interconnected with the amygdala, such as the hippocampus and the ventromedial prefrontal cortex. Further research is required to incorporate findings from animal studies into a better understanding of neural circuitry of fear in human in a translational approach.

• Journal of Veterinary Clinics
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• v.29 no.6
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• pp.494-497
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• 2012

A 6-year-old castrated male Miniature Pinscher dog was referred due to shaking, panting and inappropriate elimination during thunderstorms. The dog had noise phobia after a car accident two years ago. The intensity of the fear of noise, especially with thunderstorms, worsened during the past 3 months (thunderstorm season). Physical examination revealed hyperthermia, tachypnea (panting), mild tachycardia, and an elevated systolic blood pressure. Laboratory examination revealed mild polycythemia with a lower oxygen pressure and saturation. Based on the history, physical examination, and laboratory tests, the dog was diagnosed as a noise phobia concurrent with relative polycythemia. Treatment was initiated with behavior modification with desensitization, counter-conditioning, and medication. Music therapy was also used and appeared to be beneficial. Clinical signs including polycythemia are improved. This case indicates that relative polycythemia can be occurred by chronic mental stress, such as noise phobia in a dog.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.174-181
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• 1985

Ultrastructural changes in the chloroplast of apple fruits was examined with Malus Pumila Mill var. Fugi harvested during preclimacteric stage the subatmospheric pressure storage condition at 380mmHg, $20^{\circ}C$. Electron micrographs obtained from the fruits stored at 760mmHg, $20^{\circ}C$ indicated that the initiation of ultrastructural changes is in parallel with the onset of respiratory climacteric. Chloroplast of the apple fruits stored for 25 days is vacuolated and the lamellar system are a little disorganized. Chloroplast of the apple fruits stored for 50 days is showing extensive vacuolation, the lamellar system are completely disorganized and the plasma membrane has pulled away from the cell wall. In the case of subatmospheric presssure storage caused to delay the onset of ultrastructural changes in chloroplast such as vacuolation, disorganization of lamellar system and dispersal of stroma lamella about 2 months. These results suggested that ripening of apple fruits is correlated not only to the activity of respiration but to the involvement of ultrastructural changes in fruit cells. The evidences obtained here led to the conclusion that subatmospheric pressure treatment extends storage life of apple fruits by inhibiting ultrastructural changes of cell organelles in concomitance with respiratory activity.

• KLA journal
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• v.44 no.1 s.338
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• pp.74-85
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• 2003

일본 정부는 지난 2002년 8월 2일 각료회의에서 ‘어린이 독서활동 추진에 관한 기본 계획’을 결정하였다. 이 기본 계획은 어린이가 자주적으로 독서활동을 할 수 있도록 그 환경을 정비한다는 관점에서, 2001년 12월에 의원입법되어 공포.시행된 ‘어린이 독서활동 추진에 관한 법률’의 규정에 따라, 정부가 수립하지 않으면 안 되게 된 것이다. 이 계획을 2002년부터 2006년까지 5년에 걸친 시책의 기본 방향과 구체적인 방안을 제시한 것으로, 그 개요는 다음과 같다. 1. 가정, 지역사회, 학교를 통하여 어린이가 독서와 친해질 수 있는 기회 제공 가정교육에 관한 학습기회를 통하여 부모에게 독서의 중요성을 이해시킨다. 도서관에서의 어린이 독서활동을 추진하여 민간단체 활동을 지원한다. 학교에서의 학습활동을 통하여 독서습관을 확립하고 독서활동을 추진한다. 2. 도서자료 정비 등 제반 조건의 정비 및 충실화 도서관과 공민관 도서실 등 지역사회의 독서환경을 정비한다. 도서관 자료를 정비하고 정보화를 추진하며 사서 연수를 충실화한다. 학교도서관의 도서정비 5개년 계획, 정보화 추진, 사서교사 발령을 촉진한다. 3. 학교, 도서관및 관계기관, 민간단체의 연계.협력체제 추진 4. 사회 분위기 조성을 위한 보급.계발 어린이 독서의 날(4월 23일)을 중심으로 전국적으로 홍보한다. 홈페이지 개설로 관련정보를 광범위하게 제공한다. 일본 문부과학성은 이 기본계획에 기초하여 관계부처 등과 긴밀히 협조하여 어린이 독서활동 추진에 관한 시책을 더욱 충실히 하기로 하였다. -편집자주

• Korean Journal of Cognitive Science
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• v.29 no.1
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• pp.39-59
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• 2018

To elucidate the effect of working memory (WM) load on negative facial emotion processing, we examined ERP components (P1 and N170) elicited by fearful and neutral expressions each of which was presented during 0-back (low-WM load) or 2-back (high-WM load) tasks. During N-back tasks, visual objects were presented one by one as targets and each of facial expressions was presented as a passively observed stimulus during intervals between targets. Behavioral results showed more accurate and fast responses at low-WM load condition compared to high-WM load condition. Analysis of mean amplitudes of P1 on the occipital region showed significant WM load effect (high-WM load > low-WM load) but showed nonsignificant facial emotion effect. Analysis of mean amplitudes of N170 on the posterior occipito-temporal region showed significant overall facial emotion effect (fearful > neutral), but, in detail, significant facial emotion effect was observed only at low-WM load condition on the left hemisphere, but was observed at high-WM load condition as well as low-WM load condition on the right hemisphere. To summarize, facial emotion effect observed by N170 amplitudes was modulated by WM load only on the left hemisphere. These results show that early emotional processing of negative facial expression could be eliminated or reduced by high load of WM on the left hemisphere, but could not be eliminated by high load on the right hemisphere, and suggest right hemispheric lateralization of negative facial emotion processing.

• Journal of fish pathology
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• v.9 no.2
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• pp.157-168
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• 1996

In this study, Residue of formaldehyde and histopathological changes in formalin and neutralformalin in treated fish(Sebastes schlegeli) were observed at two different temperatures(15 and $25^{\circ}C$). Immediately after in treatment, residue of formaldehyde in formalin treated fish was show little bit higher than in neutral-formalin treated fish at $15^{\circ}C$. But, there is no difference at water temperature $25^{\circ}C$. The elimination of formaldehyde was markedly temperature-dependent. The approximated withdrawal time were 72hr and 24hr at water temperature 15 and $25^{\circ}C$. Formalin was more toxic than the neutral-formalin at the same condition. Intensity of tissues damage was increased with increasing concentration of chemical and temperature. Formalin and neutral-formalin treatments caused edema and seperation of epithelium, winding of secondary gill lamella, necrosis in the gill ; congestion and pycnosis, vacuolation in the liver ; hydropic and granulated degeneration, necrosis of epithelial cells in the proximal renal tubule ; increasing mucus cells, cracking, necrosis of epidermis and dermis in the skin tissue.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.249-256
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• 1986

The carp (Cyprinus carpio) used in the experiment were hatched in the spring this year and reared to 5.96g($4.84{\sim}6.55g$) in mean weight in a nursery pond at Daeyon fish farm, Pusan, Korea. The sample fish were exposed to different conditions of total ammonia (TA-N) concentrations 10, 20 and 30ppm and pH 6.5, 7.0, 7.5 and 8.0 at water temperatures 20, 25 and $30^{\circ}C$ for 24, 48 and 72 hours. After the procedure, the gill, liver and kidney of the fish were examined histopathologically. In this experiment, with the rise of water temperature, increase of pH and ammonia concentration, and the extension of exposure time the three organs showed the tendency of apparent abnormal changes such as hypertrophy and necrosis in their tissues. At $20^{\circ}C$ of water temperature gill tissue did not show any abnormality regardless of the change of pH at 10 ppm of ammonia concentration for 24 hours of exposure, but beyond the conditions given above, there occurred hypertrophy and the epithelium of gill lamellae was detached. The detach of gill lamellae epithelium initiated from the proximal part of the gill lamellae then gradually spread toward the uppermost tip. The heavier vacuolation of the liver was observed with the rise of water temperature and pH, and such morbid state in the liver was considered to be the result of edema in the liver tissue. The kidney showed no damage to the renal tubule epithelium at pH 6.5, but it was damaged at pH 8.0 when exposed to 30 ppm ammonia at $20^{\circ}C$ for 24 hours.

• Journal of the Korea Concrete Institute
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• v.28 no.4
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• pp.445-454
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• 2016

With the increase of decrepit facilities, construction waste increased to a certain level and now the increase is more or less stabilized. Yet construction waste still constitutes the largest portion of the overall wastes. Also, it is inevitable to spend a huge amount of the national budget due to the aggravating shortage of aggregate caused by prohibition on collection of natural aggregates as well as due to the damage to the land and environment caused by development of the sources of aggregates. As a countermeasure to the situation, the Ministry of Land, Infrastructure and Transport promulgated the quality standard for recycled aggregate to manage the usage of recycled aggregate according to its quality. But use of recycled aggregate for the purpose of high added value still remains nominal. Therefore, this research aims to study the applicability of recycled aggregate concrete as structural concrete by evaluating the quality improvement effects and the performance of the recycled aggregate concrete including recycled fine aggregate and recycled coarse aggregate that have undergone carbonation for 4 days and 14 days respectively in the condition of 60% RH, 20% $CO_2$ and $20^{\circ}C$ temperature, suggested for carbonation modifying from the advance research. The result shows carbonation modify contributed to quality improvement with 0.91% decrease in absorption rate for recycled fine aggregate and 0.7% decrease in absorption rate for recycled coarse aggregate. The physical properties and durability of the recycled aggregate made of aggregate modified by carbonation showed results similar to general concrete, which confirmed the possibility of applying the recycled aggregate made of recycled aggregate modified by carbonation to structural concrete.