• Title/Summary/Keyword: Period Characterized

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Studies on Growth and Differentiation of Suspension-Cultured Carrot Cells I. Alterations in Peroxidase Activity, Polyamine Content and Ethylene Production during Somatic Embryogenesis (당근 현탁 배양세포의 생장과 분화에 관한 연구 I. 배형성 과정에서 Peroxidase 활성, Polyamine 함량 및 Ethylene 성성의 변화)

  • 김응식
    • Journal of Plant Biology
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    • v.33 no.4
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    • pp.259-269
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    • 1990
  • Changes of peroxidase activity, polyamine content and ethylene production during somatic embryogenesis in suspension-cultured carrot (Daucus carota L.) cells were investigated. As compared with nonembyrogenic cells and their medium, embryogenic cells and their medium were characterized by higher levels of peroxidase at all times of culture period. Peroxidase in embryogenic cells showed higher oxidation activity of IAA than in nonembryogenic cells at the torpedo stage, but the IAA oxidation activity of peroxidase released into embryogenic medium was lower than that of peroxidase released into nonembryogenic medium. Peroxidase patterns of embryogenic and nonembryogenic cells showed three cathodic bands, and one anodic band, while peroxidase patterns released into embryogenic and nonembryogenic media did not show any anodic bands and the isoelectric points of cathodic peroxidase were pH 7.7, 7.5 and 6.6. Compared with nonembryogenic cells, polyamine content in embryogenic cells was increased by 15% at the torpedo stage, but polyamine ratio was constant, and ethylene production was extremely low at all times of culture period. Therefore, it is suggested that the peroxidase in embryogenic cells is correlated with embryogenesis by regulating hormone ratios through IAA oxidation, while the peroxidase isozyme patterns may be used as a biochemical marker of embryogenesis. The increase of polyamine content and the decrease of ethylene production suggest an interaction between polyamine and ethlyene during embryogenesis.

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Variation in Phytotoxicity, Movement and Residual Activity of Herbicides in Soil (토양 중에 있어서 제초제의 약해약동, 이동 및 잔효지속성)

  • Hwan-Seung Ryang;Suk-Young Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.3
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    • pp.31-46
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    • 1978
  • In order to secure the proper use of herbicides that are frequently used in Korea, the behavior of herbicides in various type of soil were studied. This study includes the variation of phytotoxicity, leaching and movement, and residual activity period of herbicides depending upon the type of soil etc. Experiments were also conducted to establish a guideline for the selection of herbicides according to the type of soil and the proper use of each herbicide in various type of soil in Korea. Experimental results showed that the behavior of herbicides could be characterized based on the series or kind of herbicides and devided into two major groups. One group (nitrofen. CNP, benthiocarb and butachlor) of herbicides showed relatively little crop injury and was very dependable. The action of this group was not remarkably influenced by soil components, rainfall and the quantity of herbicide used with the type of soil that had small adsorption capacity such as most of soil in Korea. The other group(simazine, 2, 4-D. linuron, alachlor and simetryne) showed a wide variation in it's action and retained potentially injurious effect. This group was very susceptable to using condition as well as the type of soil itself. Based on the results of various experiments the disappearance of the residual activity period of major herbicides used in upland and paddy field and the related factors were explained. It is believed that the results of this study can be used as a base for the establishment of a guideline for the proper use of each herbicide and can suggest a direction of developing new herbicides.

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Clinical Studies on 5 Cases of Multiple Sclerosis by Acupuncture Therapies (다발성 경화증 환자 5례에 대한 임상보고)

  • Kang, Kye-sung;Kwon, Ki-rok
    • Journal of Acupuncture Research
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    • v.20 no.1
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    • pp.209-217
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    • 2003
  • Background : Multiple Sclerosis is characterized by chronic inflammation, demyelinization and neurogliosis(plaque) in optic nerve, brain and spinal cord, which is recurrent visual disturbance, sensory disturbance, motor disturbance and sphincter disturbance, etc. Objective : This study was performed to evaluate the treatment of acupuncture therapy including Herbal Acupuncture and Bee venom Herbal Acupuncture in Multiple Sclerosis. Methods : We treated 5 cases of Multiple Sclerosis patients with mainly Bee venom Herbal Acupuncture therapy, and herbal Acupuncture, sa-am acupuncture form 18th september, 2001 to december, 2002. Results : 1 Of 5 cases who were treated with above, 3 patients were mildly reduced symptoms and 2 patients were no changes. 2. There are two patients who were definitely appeared the recurrent symptoms on treatment period, but decreased the remission period than before. 3. It has not shown noticeable recurrent symptoms of 3 patients. Conclusions : Bee Venom Herbal Acupuncture therapy and other acupuncture therapies were effective in reducing the recurrent symptoms and remission perod, but it was not evaluated the chief complaints on 5 cases of Multiple Sclerosis. We think that it need the further study and clinical trial for Multiple Sclerosis and other neurological diseases.

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Origins and Paleoceanographic Significance of Layered Diatom Ooze from Bransfield Strait in the Northern Antarctic Peninsula around 2.5 kyrs BP

  • Yoon, Ho-Il;Kim, Yea-Dong;Park, Byong-Kwon;Kang, Cheon-Yun;Bae, Sung-Ho;Yoo, Kyu-Chul
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.301-311
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    • 2002
  • We used diatom and porewater data of two piston cores from the central subbasin and one from the western subbasin in the Bransfield Strait in the northern Antarctic Peninsula to elucidate the depositional mechanism of the layered diatom ooze. The layered diatom ooze is characterized by an abundance of organic carbon, biogenic silica, sulfde sulfur, and lower porewater sulfate concentration. This lack of pore-water sulfate concentration in the diatom ooze interval may reflect development of reducing micro-environment in which bacterially mediated sulfate reduction occurred. The negative relationship between the total organic carbon and sulfate contents, however, indicates that sulfate reduction was partly taking place but does not control organic carbon preservation in this unit. Rather, well-preserved Chaetoceros resting spores in the layered diatom ooze indicate a rapid sedimentation of the diatom as a result of repetitive iceedge blooms on the Bransfield shelf during the cold period (around 2500 yrs BP) when the permanent seaice existed on the shelf, During this period, it is expected that the downslope-flowing cold and dense water was also formed on the Bransfield shelf as a result of sea ice formation, playing an important role for the formation of layered diatom ooze in the Bransfield subbasins.

University Virtual Environment for Attention Enhancement

  • Kang, Dong-Ju;Kim, Sun-I.
    • Journal of Biomedical Engineering Research
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    • v.23 no.2
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    • pp.155-163
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    • 2002
  • Attention Deficit Hyperactivity Disorder(ADHD) is a childhood syndrome characterized by short attention span. impulsiveness, and hyperactivity, which often leadㄴ to learning disabilities and various behavioral problems. For the treatment of ADHD, medication and cognitive-behavior therapy is applied in recent yearn Although psycho-stimulant medication has been widely used for many rears. current findings suggest that, as the sole treatment for ADHD, it is an inadequate form of intervention in that parents don't want their child to use drug and the effects are limited to the period in which the drugs are physiologically active. On the other hand, EEG biofeedback treatment studies for ADHD have reported promising results not only in significant reductions in hyperactive, inattentive, and disruptive behaviors, but also improvements in academic performance and IQ scores. However it is too boring for children to finish the whole treatment. The recent increase in computer usage in medicine and rehabilitation has changed the way health care is delivered. Virtual Reality technology provides specific stimuli that can be used in removing distractions and providing environments that get the subjects'attention and increasing their ability to concentrate. VR technology can hold a patient's attention for a longer period of time than other methods can, because VR is immersive, interactive and imaginal. Based on these aspects, we developed Attention Enhancement System (AES) using VR technology, EEG biofeedback, and cognitive training method for enhancing attention and made a clinical trial to people who have attention difficulty and behavioral problems.

Effects of Protease Inhibitors and Antioxidants on In Vitro Survival of Porcine Primordial Germ Cells

  • Lee, Chang-Kyu;Jorge A. Piedrahita
    • Proceedings of the KSAR Conference
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    • 2001.10a
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    • pp.47-47
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    • 2001
  • One of the problems associated with in vitro culture of primordial germ cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors and antioxidants, on the ability of porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally,? 2-macroglobulin, a protease inhibitor and cytokine carrier, and N-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (p〈0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layers, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of ?2-macroglobulin and antioxidants can increase the number of PGCs in vitro by suppressing apoptosis.

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The Clinical Observation on 29 Cases of Patients with Hemifacial Spasm (顔面痙攣患者 29例에 대한 臨床的 考察)

  • Jeong, Dong-Hwan;Sim, Sang-Hee;Yu, Mi-kyoung;Kim, Jong-Han;Park, Su-Yeon;Choi, Jung-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.17 no.3
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    • pp.88-94
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    • 2004
  • Hemifacial spasm is painless uncommon disorder characterized by involuntary paroxysmal movement of one side face. In the treatment of hemifacial spasm, the Western operation or non-operation therapy has many side effect such as hearing loss, exudative otitis media, facial paralysis etc. So we studied mainly the effect of cause, treatment frequency, diseased part of 29 cases with hemifacial spasm for effective clicical application of oriental medicine. The results of study are as follow; 1. It shows more female patients than male patients, and mostly patients in their forties. 2. The diseased part is shown more on left side than right side, and the left side hemifacial spasm is cured more effective. 3. The causes of hemifacial spasm are mainly stress, ignorance, overwork, and the stress, a cold are more effective causes than ignorance in. 4. The disease period is mainly within six months, and that period is the most effective time. 5. The palpebral site is the most frequent site, ineffective site. 6. The effect go with the treatment frequency is not available. 7. There is a 55 percent improvement of 29 cases.

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Development of High Strength Mg-Zn-Gd Alloys by Rapid Solidification Processing

  • Kim, Min-Chul;Yamasaki, Michiaki;Kawamura, Yoshihito
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1048-1049
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    • 2006
  • Rapidly solidified ribbon-consolidation processing was applied for preparation of high strength bulk Mg-Zn-Gd alloys. Mg alloys have been used in automotive and aerospace industries. Rapid solidification (RS) process is suitable for the development of high strength Mg alloys, because the process realizes grain-refinement, increase in homogeneity, and so on. Recently, several nanocrystalline Mg-Zn-Y alloys with high specific tensile strength and large elongation have been developed by rapidly solidified powder metallurgy (RS P/M) process. Mg-Zn-Y RS P/M alloys are characterized by long period ordered (LPO) structure and sub-micron fine grains. The both additions of rare earth elements and zinc remarkably improved the mechanical properties of RS Mg alloys. Mg-Zn-Gd alloy also forms LPO structure in -Mg matrix coherently, therefore, it is expected that the RS Mg-Zn-Gd alloys have excellent mechanical properties. In this study, we have developed high strength RS Mg-Zn-Gd alloys with LPO structure and nanometer-scale precipitates by RS ribbon-consolidation processing. $Mg_{97}Zn_1Gd_2$ and $Mg_{95.5}Zn_{1.5}Gd_3$ and $Mg_{94}Zn_2Gd_4$ bulk alloys exhibited high tensile yield strength (470 MPa and 525 MPa and 566 MPa) and large elongation (5.5% and 2.8% and 2.4%).

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Optimal Design of Multiperiod Process-Inventory Network Considering Transportation Processes (수송공정을 고려한 다분기 공정-저장조 망구조의 최적설계)

  • Suh, Kuen-Hack;Yi, Gyeong-Beom
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.9
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    • pp.854-862
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    • 2012
  • The optimal design of batch-storage network by using periodic square wave model provides analytical lot sizing equations for a complex supply chain network characterized as multi-supplier, multi-product, multi-stage, non-serial, multi-customer, cyclic system including recycling and/or remanufacturing. The network structure includes multiple currency flows as well as material flows. The processes are represented by multiple feedstock/product materials with fixed composition which are very suitable for production processes. In this study, transportation processes that carry multiple materials with unknown composition are added and the time frame is changed from single period into multiple periods in order to represent nonperiodic parameter variations. The objective function of the optimization involves minimizing the opportunity costs of annualized capital investments and currency/material inventories minus the benefit to stockholders in the numeraire currency. The expressions for the Kuhn-Tucker conditions of the optimization problem are reduced to a multiperiod subproblem for average flow rates and analytical lot-sizing equations. The multiperiod lot sizing equations are different from single period ones. The effects of corporate income taxes, interest rates and exchange rates are incorporated.

A Study on the Historical Status of Giovanni Marinoni in the Tradition of Cadastre and Cartography in 18th Century Italy (18세기 이탈리아의 지도제작의 전통과 조반니 마리노니의 역사적 위상에 관한 연구)

  • Kim, Il-Hyun;Kim, Kwan-Soo
    • Journal of architectural history
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    • v.21 no.5
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    • pp.47-56
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    • 2012
  • This research focuses on the role of Giovanni Marinioni during the formation of the modern cartography and cadastre during the 18th century. Initial study began with Giambattista Nolli's Roman map noticing not much information was available to acknowledge his activities during his Milan period before the departure to Rome. It became evident that Marinoni was a key person to understand the complex circumstances in which the professional training and formation of Giambattista Nolli took place as later worked as an anonymous intern during the elaboration of Theresian Cadastre of Milan. The other important figures are Leandro Anguissola and Giovanni Filippini. Anguissola's position and precedent work facilitated Marinoni's multidisciplinary activities that he had performed in Vienna and Milano in the field of making urban maps of those two cities. On the other hand, Filippini not only collaborated with Marinoni but also introduced Nolli in the field of cartography. These activities show transitional and dual aspects that characterized the period in which important irreversible changes that occur during the reign of Habsburg empire and in the rest of the Europe toward the formation of modern society and state. Marinoni's theories and praxis greatly influenced Nolli's later commitment under the Savoia and later on the elaboration of the 'Pianta Grande di Roma' in 1748.