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A legal regime to govern the exploitation of the natural resources of the Moon and other celestial bodies

  • Tronchetti, Fabio
    • 한국항공우주법학회:학술대회논문집
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    • 한국항공우주법학회 2008년도 제40회 국제학술발표대회
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    • pp.185-215
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    • 2008
  • The exploitation of the natural resources of the Moon and other celestial bodies represents one of the most exiting future developments in the field of space law as well as a unique occasion for the economic and social growth of mankind as a whole. The large number of benefits that are expected to be generated from the exploitation of these resources, indeed, not only will contribute to the betterment of conditions of people on Earth but also will allow mankind to face and likely solve one of the biggest problems currently affecting our planet, namely the exhaustion of the stocks of raw materials and other source of energy, such as fossil fuels. The exploitation of the natural resources of the Moon and other celestial bodies, however, has been prevented so far by the absence of dedicated space law rules allowing its orderly and peaceful development and clarifying the rights and duties of the parties involved in it. Due to the uncertainty generated by the absence of these rules, indeed, States as well as private operators have refrained from investing in the exploitation of space resources so far. The time to change this situation and to allow the exploitation of extraterrestrial resources to begin has finally come. This paper aims at fulfilling this purpose by proposing a legal regime containing specific and detailed rules to regulate the exploitation of the natural resources of the Moon and other celestial bodies.

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수소연료전지자동차의 충돌시 절연성능 평가방법에 관한 고찰 (Study on the Evaluation Method of Electrical Isolation Property for Hydrogen Fuel Cell Vehicle in Post Crash)

  • 이기연;길형준;김동욱;김동우;강대철
    • 한국수소및신에너지학회논문집
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    • 제23권6호
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    • pp.612-618
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    • 2012
  • In this paper, in order to prevent electric shock of high voltage system of HFCV after crash test, insulation performance measurement methods were studied. Under conditions of in-use, insulation performance tests can be divided into measurement method using the vehicle's own RESS as DC voltage source and measurement method using DC voltage from off-vehicle sources. However, these tests can not be applied after a post-crash because parts of high voltage system cover should be removed, and insulation performance can be influenced during these tests. Therefore, we proposed post-crash insulation performance test methods for preventing electric shock through problem analysis of previous post-crash insulation performance tests. Also, test equipment which can measure voltage absence and total energy was developed. We verified performance of the equipment through experiments with vehicle test.

Cell Division in the Absence of Mitosis: The Unusual Case of the Fucoid Ascophyllum nodosum (L.) Le Jolis (Phaeophyceae)

  • Garbary, David J.;Lawson, Greg;Clement, Kelly;Galway, Moira E.
    • ALGAE
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    • 제24권4호
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    • pp.239-248
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    • 2009
  • Fluorescence and electron microscopy were used to examine epidermal shedding in the fucoid alga, Ascophyllum nodosum. Mature meristoderm cells are ca. 50-100 x 30-40 ${\mu}m$ and highly polarized, with a single nucleus and chloroplasts near the base of the cell. Nuclei in these cells undergo mitosis when they are dividing to form a new cortical cell towards the middle of the frond, or anticlinal divisions as part of frond elongation. However, cytokinesis also occurs regularly in these cells when a new periclinal wall is deposited at about 30% of the cell length from the apical end. The newly formed distal cells are anucleate and without chloroplasts. Following cytokinesis the tangential walls then break at the thinnest point. The whole process is synchronous in adjoining epidermal cells across large areas of the frond surface, and this layer dehisces from the thallus. This is the only known plant or algal system in which cytokinesis regularly occurs in the absence of mitosis. We consider this process a novel form of programmed cell death.

Evaluation of the Genetic Toxicity of Synthetic Chemicals (XIV)-in vitro Chromosomal Aberration Assay with 11 Chemicals in Chinese Hamster Lung Cells

  • Kim, Youn-Jung;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • 제2권2호
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    • pp.89-96
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    • 2006
  • The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, to regulate and to evaluate the chemical hazard will be important to environment and human health. The clastogenicity of 11 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. 1-Chloro-3-bromopropane CAS No. 109-70-6) induced chromosomal aberrations with significance at the concentration of $185.0\;{\mu}g/mL\;and\;1,600\;{\mu}g/mL$ both in the presence and absence of metabolic activation system, respectively. Triphenyl phosphite (CAS No. 101-02-0), which is one of the most cytotoxic chemical among 11 chemicals tested revealed no clastogenicity in the range of $95.0-4.9\;{\mu}g/mL$ both in the presence and absence of metabolic activation system. From the results of chromosomal aberration assay with 11 synthetic chemicals in Chinese hamster lung cells in vitro, 1-chloro-3-bromopropane revealed a positive clastogenic result in this study.

Implementation of Spectrum Sensing with Video Transmission for Cognitive Radio using USRP with GNU Radio

  • Thien, Huynh Thanh;Vu-Van, Hiep;Koo, Insoo
    • International Journal of Internet, Broadcasting and Communication
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    • 제10권1호
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    • pp.1-10
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    • 2018
  • In cognitive radio (CR), secondary users (SUs) are able to sense the absence of primary users (PUs) in the spectrum. Then, SUs use this information to opportunistically access the licensed spectrum in the PUs' absence. In this paper, we present an implementation of real-time video transmission with spectrum-sensing between two points using GNU Radio and a National Instruments 2900 Universal Software Radio Peripheral (USRP). In our project, spectrum-sensing is implemented at both transmitter and receiver. The transmitter senses the channel, and if the channel is free, a video signal (which could be a real-time signal from a video file) will be modulated and processed by GNU Radio and transmitted using a USRP. A USRP receiver also senses the channel, but in contrast, if the channel is busy, the signal is demodulated to reproduce the transmitted video signal. This project brings in several challenges, like spectrum-sensing in the devices' environment, and packets getting lost or corrupted over the air.

Genotypic and Environmental Effects on Flour Properties in Korean Winter Wheat

  • Hong, Byung-Hee;Park, Chul-Soo;Baik, Byung-Kee
    • 한국작물학회지
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    • 제47권1호
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    • pp.1-12
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    • 2002
  • Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.

새로운 Anthracycline계 항암제 Hyrubicin ID6105에 대한 유전독성연구 (Genotoxicity Tests on Hyrubicin ID6105, a Novel Anthracycline Anticancer Agent)

  • 장호송;정미숙;이홍섭;유정수;김태영;김윤배;강종구
    • Toxicological Research
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    • 제18권4호
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    • pp.385-391
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    • 2002
  • The genotoxic potential of Hyrubicin lD6105, a novel anthracycline anticancer agent, was examined on bacterial mutagenicity, mammalian cell chromosome aberration and mouse micronucleus tests. In mutagenicity (Ames') test, Salmonella typhimurium strain TA98, TA100, TA1535 and TA1537, and Escherichia coli WP2uvrA- were treated with ID6105 at doses of 312.5, 625, 1,250, 2,500 and 5,000 $\mu\textrm{g}$/ plate with or without a metabolic activation system (S9 mix). Interestingly, ID6105 significantly enhanced the number of revertant colonies of TA98 strain at all dose levels used, in the presence or absence of S9 mix, without affecting other strains of S. typhimurium and E. coli. In chromosome aberration test using cultured chinese hamster lung fibroblasts, ID6105 (1.25, 2.5 and 5 $\mu\textrm{g}$/ml) did not increase the number of aberrant cells, compared with vehicle control. in the presence or absence of S9 mix. In addition, ID6105 treatment (2.5, 5 and 10 mg/kg) did not induce micronucleated polychromatic erythrocytes in mice. Taken together, it is suggested that ID6105 might not affect chromosome integrity in mammalian system in vitro and in vivo, although it may induce frame shift mutation of specific bacterial strain such os S. typhimurium TA98.

Significance of Perianal Lesion in Pediatric Crohn Disease

  • Jin, Won Seok;Park, Ji Hyoung;Lim, Kyung In;Tchah, Hann;Ryoo, Eell
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제21권3호
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    • pp.184-188
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    • 2018
  • Purpose: Despite the increasing incidence of pediatric Crohn disease (CD) in Korea, data on the characteristics of perianal lesions are scarce. Therefore, we aimed to investigate the characteristics of pediatric CD with accompanying perianal lesions in Korea. Methods: We retrospectively reviewed the medical records of children (age ${\leq}18$ years) with confirmed CD at Gachon University Gil Medical Center between 2000 and 2014. Patients were classified into two groups based on the presence or absence of any perianal lesions including skin tags. Additional analysis was performed according to the presence or absence of perianal perforating lesions. Results: Among the 69 CD children (mean age, 15.4 years) include in the analysis, 54 (78.3%) had a perianal lesion and 29 (42.0%) had a perianal perforating lesion. The median duration of chief complaints was longer in pediatric CD with any accompanying perianal lesions (5.40 months vs. 1.89 months, p=0.02), while there was no difference between pediatric CD with and without perianal perforating lesions (5.48 months vs. 4.02 months, p=0.18). Perianal symptoms preceded gastrointestinal symptoms in 13 of 29 (44.8%) patients with perianal perforating lesions. Conclusions: CD should be suspected in children with perianal lesions, even in circumstances when gastrointestinal symptoms are absent.

토끼 적출 신동맥에 대한 calcitonin gene-related peptide, vasoactive intestinal peptide 및 substance P의 효과 (Effect of calcitonin gene-related peptide, vasoactive intestinal peptide and substance P on isolated renal artery of rabbit)

  • 김주헌;심철수;박상은
    • 대한수의학회지
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    • 제34권4호
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    • pp.727-734
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    • 1994
  • To elucidate the effect of calcitonin gene-related peptide(CGRP), vasoactive intestinal peptide(VIP) and substance P was investigated with perivascular nerve stimulation and treatment of peptides from polygraph in the isolated renal artery of rabbit. 1. The neurogenic contraction induced by perivascular nerve stimulation was the frequency-dependent manner(264 Hz) in the isolated renal artery of rabbit. 2. CGRP and VIP caused the relaxation on the precontraction with noradrenaline($10{\mu}m$) on the presence and absence of endothelium in the isolated renal artery of rabbit. 3. Substance P caused the endothelium-dependent relaxation on the precontraction with noradrenaline($10{\mu}m$) in the isolated renal artery of rabbit. 4. CGRP and VIP inhibited the neurogenic contraction by the perivascular nerve stimulation(0.3 ms, 80 V, 50 Hz, 1 sec) on the absence and presence of endothelium in the isolated renal artery of rabbit. 5. Substance P inhibited on the neurogenic contraction by the perivascular nerve stimulation with the endothelium-dependent in the isolated renal artery of rabbit.

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기관지천식에서의 신경적 기전 (Neural Mechanism in Bronchial Asthma)

  • 최병휘
    • Tuberculosis and Respiratory Diseases
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    • 제41권2호
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    • pp.73-86
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    • 1994
  • In addition to classic cholinergic and adrenergic pathways, the existence of a third division of autonomic control in the human airways has been proved. It is called a nonadrenergic noncholinergic(NANC) nervous system, and difficult to study in the absence of specific blockers. Neuropeptides are certainly suggested to be transmitters of this NANC nervous system. It is very frustrating to understand the pathophysiologic role of these peptides in the absence of any specific antagonists. However, further studies of neuropeptides might eventually lead to novel forms of treatment for bronchial asthma. Another study of the interaction between different components of the autonomic nervous system, either in ganglionic neurotransmission or by presynaptic modulation of neurotransmitters at the end-organ will elute neural control in airway disease, particularly in asthma. Studies of how autonomic control may be disordered in airway disease should lead to improvements in clinical management. Epithelial damage due to airway inflammation in asthma may induce bronchial hyperresponsiveness. Axon reflex mechanism is one of possible mechanisms in bronchial hyperresponsiveness. Epithelial damage may expose sensory nerve terminals and C-fiber nrve endings are stimulated by inflammatory mediators. Bi-directional communication between the nerves and mast cells may have important roles in allergic process. The psychological factors and conditioning of allergic reactions is suggested that mast cell activation might be partly regulated by the central nervous system via the peripheral nerves. Studies in animal models, in huamn airways in vitro and in patients with airway disease will uncover the interaction between allergic disease processes and psychologic factors or neural mechainsms.

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