• 제목/요약/키워드: Natural respiration

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A report of three newly recorded benthic foraminiferal species from Korea

  • Somin Lee;Fabrizio Frontalini;Wonchoel Lee
    • Journal of Species Research
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    • 제12권1호
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    • pp.48-54
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    • 2023
  • Foraminifera are unicellular eukaryotes widely distributed in marine and transitional marine environments. They play important roles in marine food webs and geochemical cycles and have physiological properties like the formation of calcareous tests and nitrogen respiration. Research on species diversity, distribution and endemism are essential in biogeography and biodiversity conservation. Here, we report three unrecorded species of foraminifera (Hemirotalia foraminulosa, Planispirillina denticulogranulata and Oolina brevisolenia) collected from Jeju Island and the South Sea (Korea). Planispirillina denticulogranulata is the second Planispirillina species recorded in Korea, which can be distinguished from congeners by its tubercles on the ventral side and grooves on the spiral suture. Hemirotalia foraminulosa is differentiated from the only congener H. calvifacta by multiple-scattered pits on the umbilicus, and it is the first report of Hemirotalia from Korean water. Oolina brevisolenia has specific bifurcating costae that characterize it from other congeners. This study contributes to documentation of the foraminiferal biodiversity in Korea, moreover, provides an essential basis for the expanded studies on modern foraminifera.

토지(土地) 이용(利用) 형태(形態)의 변화(變化)와 토양(土壤) 내(內) 탄소(炭素)와 질소(窒素의 관계(關係) (Relationship between Land-Use Change and Soil Carbon and Nitrogen)

  • 손요환;이숙희
    • 한국산림과학회지
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    • 제90권3호
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    • pp.242-248
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    • 2001
  • 토지 이용 변화는 토양 내 유기물과 양분 상태에 영향을 줄 것으로 기대된다. 본 연구에서는 경기도 광주군 검단산 일대에서 과거 논으로 이용되다가 현재는 버드나무-신나무 우점의 산림으로 변한 지역, 밭에서 잣나무 인공조림지로 변한 지역, 그리고 과거부터 지속적으로 참나무류가 우점하고 있는 산림 지역 등 세 가지 토지 이용 형태를 선정하고 여기에서 토양 내 탄소와 질소의 농도, 토양 호흡, 그리고 질소 유효도 등을 측정, 비교하였다. 경작지의 휴경 후 20년이 경과한 다음, 토양 내 탄소와 질소의 농도는 토양 깊이 0-10cm, 10-20cm에서 과거 논이었던 지역이 다른 지역에 비하여 높은 것으로 나타났다. 또한 일반적으로 탄소와 질소의 농도는 표층에서 높고 토양 깊이가 증가할수록 점차 낮아지는 경향을 보였다. 이것은 유기물의 유입과 분해의 차이로 인한 축적량이 과거 논이었던 지역에서 가장 많기 때문이며, 탄소와 질소의 증가는 주로 표층에 국한한데에 기인하는 것으로 보인다. 토양 발생 이산화탄소량은 논에서 산림으로 변한 지역에서 가장 높게 나타났으며, 이는 토양 내 높은 탄소 농도와 습윤한 수분 조건 때문인 것으로 보인다. 이온교환수지봉지법으로 측정한 토양 내 질소 유효도는 토지 이용 형태에 따라 유의한 차이를 나타내었는데, 무기태 질소 $NH_4{^+}+NO_3{^-}$)의 유효도와 암모니움태 질소의 농도는 산림지역에서 가장 높고, 밭에서 산림으로 변한 지역, 논에서 산림으로 변한 지역의 순으로 점차 감소하였다.

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Net Ecosystem Productivity Determined by Continuous Measurement Using Automatic Sliding Canopy Chamber

  • Kim, Gun-Yeob;Lee, Seul-Bi;Lee, Jong-Sik;Choi, Eun-Jung
    • 한국토양비료학회지
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    • 제45권6호
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    • pp.1179-1186
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    • 2012
  • For better understanding of carbon cycle dynamics of an agro-ecosystem, an accurate assessment of seasonal and daily $CO_2$ flux is essential to understand the relationship between various environmental factors and crop productivity. We developed the automatic sliding canopy chamber (ASCC) system that measured continuous net ecosystem productivity (NEP) over whole growing season under the natural meteorological rhythm. The ASCC was composed of two main parts which were sliding part for measuring NEP, and automatic opening and closing chamber (AOCC) for measuring soil respiration (SR) on the soil surface. The ASCC was developed by using open flow method for measuring soil $CO_2$ efflux. The disturbance of natural meteorological condition was minimized by opening the base frames. In the field test with barley (Hordeum vulgare L.), NEP was calculated at $140mg\;CO_2\;m^{-2}h^{-1}$ on a clear day using continuous data and eliminated the possibility of overestimate about 16% using one hour data during the day time. Unlike other small scale chamber system, installation on cropping-field made it possible to take any modifications which might be caused by natural environmental condition.

효모에서 발현된 유전자 재조합 탈메치오닌 인간 성장호르몬의 일반 약리작용 (General Pharmacology of Recombinant Human Growth Hormone without N-Terminal Methionine Expressed in Saccharomyces cerevisiae)

  • 이은방;신국현;김운자;윤기영;천선아;채윤정
    • 약학회지
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    • 제36권1호
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    • pp.17-25
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    • 1992
  • The general and some other pharmacological actions of growth hormone without N-terminal methionine(rhGH) were investigated in animals. The hormone had no influences on the central nervous system and on body temperature at a high oral dose of 40 IU/kg in animals. It had neither analgesic nor antiepileptic actions at the high doses. In the isolated ileum and trachea of guinea-pig and isolated stomach fundus and uterus of rat, it showed neither contractive nor relaxing effects at a concentration of $1{\times}10^{-3}\;IU/ml$ in bath, and no inhibitory action at a dose of $1{\times}10^{-3}\;IU/ml$ against the contractions produced by histamine ($5{\times}10^{-5}\;g/ml$), serotonin($1{\times}10^{-5}\;g/ml$), acetylcholine($1{\times}10^{-5}\;g/ml$) and oxytocin($5{\times}10^{-3}\;IU/ml$). Furthermore, the intravenous injection of 20 IU/kg rhGH had no influences on the normal blood pressure and respiration in rabbits. These negative results in pharmacological profile are thought that the hormone may not elicit serious side effects. On the other hand, the rhGH exhibited a weak inhibitory action of glucose tolerance in normal rats, significantly lowered the blood glucose contents in adrenalectomized rats 20 min after i.v. administration of 80 IU/kg, and showed a significant inhibitory effect on in vitro glycerol release in epinephrine-stimulated epididymal fat pad segments of rats.

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유해가스 및 분진이 발생하는 작업장내의 자연환기에 대한 연구 (The Study on Natural Ventilation in Working Places with the Noxious Gas and Dust)

  • 추병길;김철;최종욱;유수열
    • 한국안전학회지
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    • 제15권1호
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    • pp.72-79
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    • 2000
  • In recent, occupational diseases in harmful working places become a social issue. It is the well-known fact that a respiration in polluted working places exert a serious effect on health of workers. Accordingly, the cutting off contaminants air originally is the best way to improve working environments. In these cases, ventilation systems should be essentially installed to dilute or exhaust the contaminated indoor air. In this study, we investigated the characteristics of ventilation system of the noxious gas in working indoor places with natural ventilation by using COMET. The numerical simulations were carried out the natural ventilation with two phase(air, dust). For turbulent flow, Reynolds stresses were closed by the standard $\kappa$-$\varepsilon$ model. The results are as follows ; 1) In the natural exhaust in the working place, the flows of the central region have a more rapid velocity vector than the right and left one. 2) Numerical results show that the distribution of contaminants concentration have greater influence on convection than the case of diffusion by government of velocity vectors. 3) To observe the velocity variation with distance, three location of distance are considered. As results, it shows that the velocity are 0.075(m/s) at y=5(m), 10(m) and mean concentration are raised 10.6% at y=5(m), 10(m). 4) We have presented the useful data for the adequate counterplan in the harmful working places by carrying out the various investigation of the natural ventilation.

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Heat sensitivity on physiological and biochemical traits in chickpea (Cicer arietinum)

  • Jain, Amit Kumar
    • Advances in environmental research
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    • 제3권4호
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    • pp.307-319
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    • 2014
  • Four chickpea cultivars viz. kabuli (Pusa 1088 and Pusa 1053) and desi (Pusa 1103 and Pusa 547) differing in sensitivity to high temperature conditions were analyzed in earthern pot (30 cm) at different stages of growth and development in the year of 2010 and 2011. Pusa-1053 (kabuli type) showed maximum photosynthetic rate and least by Pusa-547 (desi type), whereas maximum cell membrane thermostability were recorded in Pusa-1103 and minimum in Pusa-1088. Among the treatments, the plants grown under elevated temperature conditions had produced 13.01% more significant data in comparison to plants grown under continuous natural conditions. Stomatal conductance were reduced 44.25% under elevated temperature conditions than natural conditions, whereas 35.56%, when plants grown under initially natural conditions upto 30DAS, then 30-60DAS elevated temperature and finally shifted to natural conditions till harvest. In case of Pusa-1103, stomatal conductance was maximum as compared to rest of 2.7% from Pusa-1053, 8.9% from Pusa-1088, and 10.3% in Pusa-547 throughout the study. Plants grown under continuous elevated temperature conditions had produced 15.30% and 15.32% more significant membrane thermostability index in comparison to continuous natural conditions at vegetative stage and 19.40% and 18.44% at flowering stage, while the better response was recorded at pod formation stage. Pusa-1053 had given 2.8% more membrane thermostability index than Pusa-1088 and Pusa-1103 had given 1.6% more membrane thermostability index than Pusa-547 in the present study. The membrane disruption caused by high temperature may alter water ion and inorganic solutes movement, photosynthesis and respiration. Thus, thermostability of the cell membrane depends on the degree of the electrolyte leakage.

General Pharmacology of $^{13}C$-Urea Powder Preparation in ${Helikat}^{TM}$

  • Lee, Eun-Bang;Cho, Sung-Ig;Jung, Chun-Sik
    • Biomolecules & Therapeutics
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    • 제6권4호
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    • pp.406-411
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    • 1998
  • The pre-mixed $_{13}C$-urea powder preparation in ${Helikit}_{TM}$ for test of Helicobacter pylori was evaluated for pharmacological properties. The oral doses of the preparation used in mice were 30-fold as compared to human doses. The results obtained in the present study demonstrate that spontaneous movement, hexobarbital-induced hypnosis, rotarod performance, body temperature, acetic acid-induced writhing syndrome, chemical and electroshock convulsion, pupil size and intestinal propulsion had not been affected at the oral doses of 230, 700 and 2100 mg/kg in mice. The blood pressure was slightly elevated as given intravenously in rats at a dose of 5 mg/kg of the preparation, but respiration was not influenced at the dose. In isolated guinea pig ileum and rat fundus preparation, the preparation at a concentration of $1{\times}10^{4}$ g/ml neither caused any direct effect nor inhibited the contraction produced by acetylcholine, histamine or 5-hydroxytryptamine. These results reported here provide evidence that pre-mixed $^{13}C$ 13/C-urea powder preparation is free of general pharmacological properties performed in oral administration.

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사과과실 저장성에 미치는 에틸렌흡착제의 효과 (Effect of Ethylene Adsorbent on Apple Fruit Quality during Storage)

  • 안영직;최종승;민병훈;이경욱
    • 자연과학논문집
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    • 제8권2호
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    • pp.169-173
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    • 1996
  • 사과 과실의 PE필름 포장 저장 중 에틸렌을 제거하여 저장성을 증대시키기 위한 에틸렌흡착제의 사용이 과실의 저장력에 미치는 영향을 조사하고 자 본 시험을 수행하였다. 에틸렌흡착제 처리는 저장 중 경도저하가 현저하게 억제되었고 흡착제양이 많을수록 억제효과가 크게 나타나는 경향을 보였으나 과실의 당함량과 산함량에는 영향이 없었으며, 과실의 에틸렌 발생량과 호흡량이 감소되었다. 에틸렌흡착제의 처리량은 과실 10kg 당 30g 이상이 적당하였다.

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유전 알고리즘을 이용한 폭기조내 용존산소농도 제어 (Control of the Dissolved Oxygen Concentration in the Aeration Using Genetic Algorithms)

  • 김창현;허동렬;김상효;정형환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2479-2481
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    • 2000
  • It is the time-varying dissolved oxygen(DO) dynamics that requires controlling for maintaining the DO concentration in the aeration tank. Many linear controllers have thus been applied. Because of the nonlinearity of the oxygen transfer function together with the time-varying respiration rate, however, the linear controllers are found to poorly perform in many cases. To overcome this limitation, a number of advanced controlling techniques have been developed and applied. In this study, designed GA-PI Controller using genetic algorithm(GA). Genetic algorithms(GAs) are search algorithms based on the mechanics of natural selection and natural genetics. As result of computer simulation, GA-PI controller shows the better control performance especially under the condition of the continuously changing DO set-point. This result represents that GA-PI controller can be a good measure to control the DO concentration in the SBR process which requires the sequential DO set-point change to accomplish the nitrification and denitrification in a single reactor.

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산소중독시 가토의 [A-a] gas Gradient 의 변화 (Changes of [A-a] gas Gradient in Rabbits with Oxygen Toxicity)

  • 이두연
    • Journal of Chest Surgery
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    • 제20권1호
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    • pp.1-12
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    • 1987
  • Respiratory care with oxygen inhalation is often a necessity to maintain life, and it is one of the important therapeutic adjuncts in respiratory disease and in intensive care after surgery. However, it has been reported that oxygen toxicity occurs after prolonged exposure to 100% 0, [Smith, 1899; Kistler et al. 1967; Schaffner et al. 1967; Rowland and Newman, 1969. Subjective symptoms of oxygen toxicity include tracheal irritation, frequent cough, some burning sensation in the trachea, tachypnea, severe dyspnea, etc. [Welch, 1963; Fisher et al, 1968; Milier et al, 1970; Clark and Lambertsen, 1971; Sackner, 1975]. Pathologic findings are atelectasis, injuries to the pulmonary capillaries and hemorrhage in the alveoli in gross specimens. There can be inflammation, proliferation of fibrin, thickening of alveolar membranes, degeneration of collagen fibers and interstitial edema in the microscopic findings. [Penrod, 1956; Cedergren, 1959; Bean, 1965; Schaffner, 1967]. Dubois and colleagues [1961] found that the amount of pulmonary surfactant was decreased in oxygen toxicity and atelectasis followed by the decreased pulmonary surfactant. Many authors reported that vital capacity, inspiratory force, pulmonary compliance, pulmonary capillary blood flow and pulmonary elasticity were deceased and arteriovenous shunting increased. [Comroe et al, 1945; Fuson et al, 1965; Kistler et al, 1966; Knowles and Blenner-hassett, 1967; Barber et al, 1978]. Many human volunteers were examined after prolonged exposure in a high oxygenated chamber and there were a few reports on animals with oxygen toxicity, subjects including rabbits. Gas partial pressures of alveoli and arteries were measured in rabbits exposed to 100% $O_2$ and the alveolar-arterial gas gradients were analyzed, which is the basis for the study of oxygen toxicity. These rabbits were divided into two groups; rabbits under natural respiration, and second group under artificial respiration with a respirator. The alveolar $PO_2$ [$P]AO_2$] and $PCO_2$ [$PACO_2$], and the arterial $PO_2$ [$PaO_2$] were measured under varying $O_2$ pressures; 15% $O_2$, 21% $O_2$ and 100% $O_2$.

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