• 대한의용생체공학회:의공학회지
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• 제32권1호
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• pp.55-60
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• 2011

Although sound intensity is considered as one of important factors in auditory processing, its neural mechanism in auditory neurons with limited dynamic range of firing rates is still unclear. In this study, we examined the effect of sound intensity adaptation on the change of glucose metabolism in a rat brain using [F-18] micro positron emission tomography (PET) neuroimaging technique. In the experiment, broadband white noise sound was given for 30 minutes after the [F-18]FDG injection in order to explore the functional adaptation of rat brain into the sound intensity levels. Nine rats were scanned with four different sound intensity levels: 40 dB, 60 dB, 80 dB, 100 dB sound pressure level (SPL) for four weeks. When glucose uptake during the adaptation of a high intensity sound level (100 dB SPL) was compared with that during adaptation to a low intensity level (40 dB SPL) in the experiment, the former induced a greater uptake at bilateral cochlear nucleus, superior olivary complexes and inferior colliculi in the auditory pathway. Expectedly, the metabolic activity in those areas linearly increased as the sound intensity level increased. In contrast, significant decrease interestingly occurred in the bilateral auditory cortices: The activities of auditory cortex proportionally decreased with higher sound intensities. It may reflect that the auditory cortex actively down-regulates neural activities when the sound gets louder.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.175-175
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• 2017

To understand molecular mechanisms underlying adaptation of plant cells to saline stress and stress memory, we developed Arabidopsis callus suspension-cultured cells adapted to high salt. Adapted cells to high salt exhibited enhanced tolerance compared to control cells. Moreover, the salt tolerance of adapted cells was stably maintained even after the stress is relieved, indicating that the acquired salt tolerance of adapted cells was memorized. In order to characterize metabolic responses of plant cells during adaptation to high salt stress as well as stress memory, we compared metabolic profiles of salt-adapted and stress-memorized cells with control cells by using NMR spectroscopy. A principle component analysis showed clear metabolic discrimination among control, salt-adapted and stress-memorized cells. Compared with control cells, metabolites related to shikimate metabolism such as tyrosine, and flavonol glycosides, which are related to protective mechanism of plant against stresses were largely up-regulated in adapted cell lines. Moreover, coniferin, a precursor of lignin, was more abundant in salt-adapted cells than control cells. Cell morphology analysis using transmission electron microscopy indicated that cell wall thickness of salt-adapted cells was significantly induced compared to control cells. Consistently, salt adapted cells contained more lignin in their cell walls compared to control cells. The results provide new insight into mechanisms of plant adaptation to saline stress as well as stress memory in metabolic level.

• Journal of Nutrition and Health
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• 제28권10호
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• pp.1031-1039
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• 1995

Dietary mehaden oil enhances mucosal hyperplasia that normally occurs after massive small bowel resection. In contrast, dexamethasone and aspirin inhibit the adaptation response. In order to gain insight on the mechanism of these effects, male Sprague-Dawley rats weighing approximately 150gram were randomly divided into two groups and fed diet containing either 15% safflower oil or 14% menhaden oil and 1% safflower oil. Ten days later they were subjected to 70% jejunoilear resection. Immediately after surgery each group was further divided into two groups and receive either vehicle or 125ug/kg/day dexamethasone subcutaneously. All animals were sacrificed seven days after the surgery, and the remaining intestine was removed and divided at the anastomotic site. Dexamethasone, which decreased gut hyperplasia in both dietary groups, decreased both serum IGF-I levels and ileral PGE2 synthesis. Menhaden oil enhanced gut hyperplasia, but did not increase IGF-I or IGF-II levels in serum. PGE2 synthesis was lower in the ileum of menhaden oil-fed rats compared to that of safflower oil-fed rats. The effects of menhaden oil on adaptation did not apper to be mediated either through IGFs or PGE2 synthesis. Other factors could have played a role in enhancing adaptation following menhaden oil feeding.

• The Journal of Asian Finance, Economics and Business
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• 제6권4호
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• pp.281-286
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• 2019

The study aims to analyze the adaptation strategies and resilience of tobacco farmers to face unfavorable trading system. The research method refers to a qualitative approach with phenomenological models and case studies. The findings revealed tobacco farmers in Jember developed various adaptation strategies and resilience through farmer group organizations, partnerships, self-capacity building and access to financial institutions based on economic, social, cultural, and experience values from various sources and interactions among fellow tobacco farmers. The tobacco trading system, which is left to the market mechanism, results in low bargaining power of farmers, this encourages tobacco farmers to develop various adaptation and survival strategies, namely through collective activities of farmer groups, partnerships and self-development and access to financial institutions. Dealing with the unfavorable tobacco trading system, tobacco farmers do not switch to other commodity farming but adapt and make Jember a center for tobacco production in East Java and Indonesia. From this findings, it suggests to the government as the regulator does not only provide subsidies for tobacco farmers, but also must provide various technical assistance to increase the ability of tobacco farmers. More importantly, regulations must be made benefit tobacco farmers other than corporations so that equality can be enjoyed by tobacco economy players.

• 미생물학회지
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• 제28권3호
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• pp.249-257
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• 1990

In the course of operating the accommodative and detoxifying mechanism against cadmium, its physio-biochemical changes were observed in Klebsiella aerogenes ATCC 10031. Changes of enzyme activity concerned phosphate metabolism, changes of phospholipid composition and in view of energy metabolism the changes of the nucleotide pool were examined. Activities of both alkaline and acid phosphatase were derepressed 4-10 folds under cadmium added cultures. Moreover, production of phospholipid such as lysophosphatidyl choline (LPC), phosphatidyl serine (PS) and phosphatidyl ethanolamone (PE) was increased and uridylate nucleotide pool was increased under Cd-surplus culture. These results i.e. overproduction of phosphatase catalyzing phosphate residue, increase of the production of PE and PS which have a close affinity with cadmium, and indrease of uridylate nucleotide pool used as a carrier of polysaccharide synthesis like bacterial capsule exhibited cellular responses for active defence against Cd-pressure. It was postulated that these phenomena should play another assistant roles in Cd-detoxifing mechanism.

• 환경정책연구
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• 제14권1호
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• pp.53-83
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• 2015

최근 기후변화 적응 분야의 연구에 있어 리스크 평가가 적응정책 수립의 중간 과정으로서 논의되고 있다. 기후변화 리스크 평가는 기존의 기후변화 영향평가, 취약성 평가와 더불어 적응정책을 도출하는 데 있어, 관리방안 구성의 매개체로서 역할을 하는 것으로 알려져 있으며 영국 적응정책 수립에 활용되었다. 목적은 영국의 국가 적응정책 수립에 활용된 정성적 리스크 평가의 방법의 일부를 국내 적응정책 수립의 각 부문에 대해 적용하고, 이를 유형화하여 관리방안의 방향을 도출하고자 하는 것이다. 방법으로는 델파이 기법을 응용한 전문가 설문조사와 Klinke and Renn(2002)이 제안한 유형화의 방법을 적용하였다. 논문에 사용된 기후변화 리스크는 국내 기후변화 영향 및 취약성 보고서, 국가기후변화적응대책, 영국 리스크 평가에 사용된 목록 등을 활용하였다. 분석결과 총 125개 리스크 중 42개가 선택되었다. 리스크의 영향정도와 관리의 시급성이 높은 리스크의 경우는 이상기상, 극한기상과 관련하여 반복적이고 피해규모가 커지는 풍수해 관련 리스크가 다수를 차지하였다. 또한, 생태계 변화, 기반시설 대응과 같은 중장기적 대응이 필요한 리스크도 다수 도출되었다. 국내의 기후변화 리스크는 사회적 신뢰와 촉발메커니즘, 책임성 등이 관리에서 요구되는 유형으로 나타났다. 시사점으로 시민사회의 역량강화와 상호간 신뢰, 정책구성에 있어 시민참여 등을 통해 자율적 적응의 폭을 넓일 것을 제안하였다.

• ETRI Journal
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• 제27권1호
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• pp.43-52
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• 2005

In this paper, we introduce an adaptive radio resource allocation for IP-based mobile satellite services. We also present a synchronous multibeam CDMA satellite system using an orthogonal resource sharing mechanism among downlink beams for the adaptive packet transmission. The simulation results, using a Ka-band mobile satellite channel and various packet scheduling schemes, show that the proposed system and resource allocation scheme improves the beam throughput by more than two times over conventional systems. The simulation results also show that, in multibeam satellite systems, a system-level adaptation to a user's channel and interference conditions according to user locations and current packet traffic is more efficient in terms of throughput improvement than a user-level adaptation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.46-51
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• 2004

This paper presents an adaptive control method based on parameter linearization for incompletely restrained wire-suspended mechanisms. The main purpose of this control method is utilizing it in a walking assist service robot for elderly people. This method is computationally simple and requires neither end-effector acceleration feedback nor inversion of estimated inertia matrix. In the proposed adaptive control law, mass, moment of inertia and external force and torque on the end-effector are considered as components of parameter adaptation vector. Nonlinear simulation for walking an elderly shows the effectiveness of the parameter adaptation law.

• Journal of Plant Biotechnology
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• 제32권1호
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• pp.1-14
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• 2005

Plant responses to salinity stress is critical in determining the growth and development. Therefore, adaptability of plant to salinity stress is directly related with agriculture productivity. Salt adaptation is a result of the integrated functioning of numerous determinants that are regulated coordinately through an appropriate responsive signal transduction cascade. The cascade perceives the saline environment and exerts control over the essential mechanisms that are responsible for ion homeostasis and osmotic adjustment. Although little is known about the component elements of salt stress perception and the signaling cascade(s) in plant, the use of Arabidopsis plant as a molecular genetic tool has been provided important molecular nature of salt tolerance effectors and regulatory pathways. In this review, I summarize recent advances in understanding the molecular mechanisms of salt adaptation.

• 대한치과교정학회지
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• 제19권2호
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• pp.155-163
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• 1989

Indirect bonding is done by placing the brackets on a model in the laboratory and using a template or tray to transfer the laboratory positioning to the teeth. The advantages of this technique are 1. decreased chair time 2. less patient discomfort 3. accuracy of a attachment placement 4. good adaptation of attachment to tooth contour 5. occlusal relationship of brackets and opposing teeth can be checked The disadvantages of the technique are 1. complex laboratory procedure 2. sometimes difficult on very short clinical crowns 3. teeth with crowns, large buccal restoration will not bond 4. may not be fitted close, if poor adaptation 5. likely to be disturbed setting Several indirect bonding techniques have proved reliable in clinical practice. However, they differ in the way the brackets are attached temporarily to the model, the type of transfer tray or other mechanism used, the adhesive or sealant employed, whether segmented or full bonding used, and the way the transfer is removed so as not to exert excessive force on a still maturing bond.