• 제목/요약/키워드: playa

검색결과 372건 처리시간 0.033초

북부 아르헨티나 붕산염 광상 조사: 살리나스그란데스 광상을 중심으로 (Survey of Borate deposit in Northern Argentina: Salinas Grandes Borate deposit)

  • 박상준;이한영
    • 한국지구과학회지
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    • 제30권7호
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    • pp.801-809
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    • 2009
  • 북부 아르헨티나 후후이주 동부에 위치하는 살리나스그란데스 붕산염(borate) 광상은 플라야 주변부에 배태되는 플라야(playa)형 증발광상이다. 이 광상에서 산출되는 붕산염광물은 주로 울렉사이트(ulexite, $NaCaB_5O_9{\cdot}H_2O$)로 붕소의 주공급원은 주변 화산암일 것으로 추정된다. 아르헨티나 후후이주 동부는 아건조 기후의 알티플라노-푸나 고평원에 위치한다. 중생대 및 신생대 화산암체는 붕소의 주요 공급원으로 생각되며, 플라야는 이들 붕소가 침전되는 주요분지 역할을 하여 이 지역은 붕소의 이동과 침전을 위한 좋은 지형적 지구조적 조건을 보인다. 따라서 향후 이 지역의 붕산염 광체에 대한 지속적인 탐사가 필요 할 것으로 생각된다.

치화화사막에서 뿌리의 분해과정에 따른 질소함량의 변화 (Changes of Mass Loss and Nitrogen Content during Root Decomposition in the Chihuahuan Desert)

  • 문형태
    • The Korean Journal of Ecology
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    • 제17권3호
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    • pp.311-318
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    • 1994
  • 치화화 사막에서 몇 가지 식물 뿌리의 분해율과 분해 과정에 따른 질소함량의 변화를 조사하였다 (1986년 10월 ~ 1990년 4월). 뿌리의 분해는 리그닌 함량과 역상관 관계를 보였다(r=-0.84, n=5, p<0.05). 1년생 광엽초본인 Baileya multiradiata의 분해율이 가장 높았고 다년생 협엽 초본인 Panicum obtusum의 분해율이 가장 낮았다. 지역에 따른 분해율은 playa에서 가장 낮았다. Baileya multiradiata를 제외하고 모두 분해 초기에 질소의 무기화가 있은 다음 질소의 부동화가 나타났다. Baileya multirdiata의 뿌리는 분해 초기부터 질소함량이 계속 증가하는 것으로 나타났다. 다년생 협엽초본 뿌리의 리그닌 함량은 광엽초본 뿌리의 리그닌 함량보다 높았다.

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Design and Implementation of AN Entertainment Golf Robot

  • Kim, Byoung-Soo;Oh, Kwan-Taek;Park, Young-Ho
    • International Journal of Contents
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    • 제3권4호
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    • pp.36-40
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    • 2007
  • Robot has been developed as something to help human beings, and robot will be very important field as an entertainment. This paper intends to contribute to developing golf robot as an entertainment using AVR ATmega Chips. It is believed that the entertaining robot giving a pleasure to human beings has good prospects for the rapid growth along with other robot industry. Golf robot developed in this paper has been developed for entertainment and has a similar sense in comparison with the real golf. This golf robot is represented in the way of putting the ball in the hall by hitting the ball just like the actual golf game and putting through making robot come close to the ball with the putting robot. This golf robot can playa game with several people like the actual golf if many putting robots can be used. It is, therefore, considered that the development of golf robots for entertainment using AVR has a high value of the golf robot as an entertainer on the ground that it can playa real golf.

Toll-like Receptors in Host Defense and Immune Disorders

  • Lee, Joo-Y.
    • Toxicological Research
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    • 제23권2호
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    • pp.97-105
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    • 2007
  • Toll-like receptors (TLRs) playa crucial role in initiating and regulating innate and adaptive immune responses by detecting invading microbial pathogens. TLRs can also respond to non-microbial molecules derived from damaged tissue. Accumulating evidence suggests that deregulation of TLRs results in the dysfunction of immune system and ultimately increases the risk of many immune and inflammatory diseases including infectious diseases, allergy, and autoimmune diseases. Therefore, understanding how the immune system is controlled by TLRs will provide new insight to find the way to prevent or treat infectious diseases and immune disorders.

A Study on The Mechanism of Oxidative Stress, Screening of Protective Agents and Signal Transduction of Cell Differentiation in Cultured Osteoblast and Osteoclast Damaged by Reactive Oxygen Species

  • Park, Seung-Taeck;Han, Du-Suk
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 춘계학술대회 논문집
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    • pp.66-67
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    • 2003
  • It is well known that osteoblasts and osteoc1asts playa key role in bone metabolism. They involve in osteoformation or bone destruction which are ragulated by various factors such as thyroid hormone, parathyroid hormone, estrogen, growth factor and cytokine. Recently, it is demonstrated that oxidative stress is one of pathological factors in bone metabolism, but it is left unknown about mechanism between oxidative stress and bone metabolism.(omitted)

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MOLECULAR MECHANISMS OF CARDIOPROTECTION BY A NOVEL GRAPE SEED PROANTHOCYANIDIN EXTRACT

  • Bagchi, Debasis;Preuss, Harry G.;Das, Dipak K.
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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    • pp.20-21
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    • 2001
  • Free radicals and oxidative stress playa crucial role in the pathophysiology of a broad spectrum of cardiovascular diseases including congestive heart failure, valvular heart disease, cardiomyopathy, hypertrophy, atherosclerosis and ischemic heart disease. We have demonstrated that IH 636 proanthocyanidin extract (GSPE) provides excellent protection against free radicals in both in vitro and in vivo models, and exhibits significantly better efficacy as compared to vitamins C, E and $\beta$-carotene.(omitted)

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Microglia and neuroinflammation: implications in neurodegenerative diseases

  • Suk, Kyoung-Ho
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2007년도 Proceedings of The Convention of The Korean Society of Applied Pharmacology
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    • pp.15-22
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    • 2007
  • Increasing evidence indicates that microglia-driven chronic inflammatory responses playa pathological role in the central nervous system. Activation of microglia is pivotal in the initiation and progression of neuroinflammation. Inhibition of the microglial activation may provide an effective therapeutic intervention that alleviates the progression of the neurodegenerative diseases. Anti-inflammatory agents may be a useful candidate for such a therapeutic approach. Continual investigation of the mechanisms underlying microglial activation and regulation of neuroinflammation by endogenous or exogenous factors would not only lead to the discovery of novel neuroprotective agents, but also help to understand complex pathophysiology of neurodegenerative diseases.

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Focus and Prosodic Structure

  • Oh, Mi-Ra
    • 음성과학
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    • 제8권1호
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    • pp.21-31
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    • 2001
  • The effects of focus on prosodic phrasing, F0, and duration are investigated paying attention not only to the target of focus but also to the constituents that are outside the domain of focus in Korean. We find that the constituents preceding and following the focused word tend to be dephrased. Dephrasing does not always cover up to the Intonation Phrase boundary contrary to Jun's (1993) claim. Dephrasing caused by focus determines F0 and durational difference between focused and neutral sentences. Syntactic constituency is also shown to playa role in prosodic phrasing.

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Modulation of Cloned T-type Calcium Channels

  • Jeong, Seong-Woo
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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    • pp.20-21
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    • 2002
  • The inflow of Ca$\^$2+/ through voltage-activated T-type calcium channels (T-channels) regulates a variety of cellular functions including neuronal excitability, cardiac pacemaker activity, hormone secretion, smooth muscle contraction, and fertilization. Not only are T-channels enormously important for the normal operation of cells, they also playa critical role in pathophysiological conditions such as cardiac hypertrophy and absence epilepsy.(omitted)

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Effect of Angiotensin II on Synaptic Transmission in the Rat Subfonical Organ

  • Lee, Ho-Sung;Han, Seong-Kyu;Ryu, Pan-Dong
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1999년도 학술발표회 진행표 및 논문초록
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    • pp.59-59
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    • 1999
  • Circulating substances can directly access the neurons in circumventricular organ (CVO) located on the border of cerebral ventricles. The neurons in CVO are considered to playa pivotal role in blood-brain communication. In subfonical organ (SFO), a CVO in forebrain, angiotensin II (AII) is mown to reduce A type $K^{+}$ current and input resistance, but enhance firing rate.(omitted)

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