• Title/Summary/Keyword: Peripheral zone

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Neurogenesis in the Adult Brain (성체 뇌 조직의 신경발생)

  • Kim, Sik-Hyun;Kim, Sang-Su
    • PNF and Movement
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    • v.6 no.3
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    • pp.37-51
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    • 2008
  • Purpose : This paper focuses on the emerging concept that adult central nervous system neurogenesis can be regulated by various physical activity, enriched environment, and pathological conditions. Neurogenesis-the production of new neuron-is an ongoing process that persists in the adult brain of mammalian, including humans. Result : The adult brain was thought be limited in its regenerative function. However, this concepts changed, recent evidence of neurogenesis in certain adult brain areas such as SVZ(subventricular zone) and SGZ(subgranular zone) in hippocampus, raised possibility for improved treatment for patient with stroke. Neural plasticity has an adaptive purpose, because an ability of the brain to change in response to peripheral stimulation, physical activity, experience, and injury. Conclusions : The major function of the neurogenesis in adult brain seems to be replacing the neuron that die regularly in discrete adult brain regions. These cells are capable of functionally integrating into neighboring neural cells, and reconnecting to the correct neural networks. This review suggest that various intervention, including physical activity, voluntary movement training, skilled forelimb reaching training, and enriched environment, induced neural cell production in certain adult brain, and associated with functional recovery after stroke.

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Marangoni Convection Effects on Crystal Growth (결정 성장에서 Marangoni 대류의 영향)

  • 강승민;최종건;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.2 no.2
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    • pp.77-82
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    • 1992
  • When a crystal is grown by FZ process, the melt zone is located at between the solid of upper and lower side and is kept by the solid-liquid interface tension. On the surface of the melt zone, a surface tension gradient is occured by the difference of temperature and solute concentration, it is the driving force of marangoni flow. The crystal even in the steady state growth can become imperfect for the dislocation distribution and the solute concentration in the peripheral region of the crystal are higher than those in the inner part and the probability of the formation of the defects such as voids, bubble penetration, secondary phase creation and crack is high near the solid-liquid interface. This is because the solid -liquid interface becomes irregular because of the local variation of temperature in that region due to marangoni convection.

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Image Analysis of Computer Aided Diagnosis using Gray Level Co-occurrence Matrix in the Ultrasonography for Benign Prostate Hyperplasia (전립선비대증 초음파 영상에서 GLCM을 이용한 컴퓨터보조진단의 영상분석)

  • Cho, Jin-Young;Kim, Chang-Soo;Kang, Se-Sik;Ko, Seong-Jin;Ye, Soo-Young
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.184-191
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    • 2015
  • Prostate ultrasound is used to diagnose prostate cancer, BPH, prostatitis and biopsy of prostate cancer to determine the size of prostate. BPH is one of the common disease in elderly men. Prostate is divided into 4 blocks, peripheral zone, central zone, transition zone, anterior fibromuscular stroma. BPH is histologically transition zone urethra accompanying excessive nodular hyperplasia causes a lower urinary tract symptoms(LUTS) caused by urethral closure as causing the hyperplastic nodule characterized finding progressive ambient. Therefore, in this study normal transition zone image for hyperplasia prostate and normal transition zone image is analyzed quantitatively using a computer algorithm. We applied texture features of GLCM to set normal tissue 60 cases and BPH tissue 60cases setting analysis area $50{\times}50pixels$ which was analyzed by comparing the six parameters for each partial image. Consequently, Disease recognition detection efficiency of Autocorrelation, Cluster prominence, entropy, Sum average, parameter were high as 92~98%.This could be confirmed by quantitative image analysis to nodular hyperplasia change transition zone of the prostate. This is expected secondary means to diagnose BPH and the data base will be considered in various prostate examination.

China's Diplomatic Challenges and Prospect in the Xi Jinping Era (시진핑 시대 중국의 외교적 과제와 전망)

  • Cho, Young Nam
    • Strategy21
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    • s.33
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    • pp.5-36
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    • 2014
  • This article aims to analyze the diplomatic challenges currently facing China as well as the foreign policy the Xi Jinping administration is adopting to address them. With these purposes in mind, it will look into three areas: first, diplomatic tasks confronting the Xi leadership; second, foreign policy that the Xi administration has implemented since the 18th Party Congress in 2012; and third, the prospects for China's foreign policy under the Xi leadership. As the Xi Jinping administration entered into office, it has encountered two major diplomatic challenges. One is the searching for a new foreign policy, and the other the restructuring of the existing foreign affairs and national security systems. The Xi administration, during its first year in office, has responded actively to tackle these issues. To begin with, it has attempted to make some adjustments on foreign policy while maintaining the Deng Xiaoping line of foreign policy. One of these modifications is placing emphasis on national "core interest," as illustrated by changes in guideline for maritime conflicts, pushing for building maritime power, and proclamation of Air Defense Identification Zone in the East China Sea. Second is the decision on the new guideline for peripheral diplomacy. That is, the administration regarded creating peaceful and stable environments to realize "Chinese Dream" as an important goal of foreign policy, and proposed such new guiding ideology as "familiarity, integrity, benefit, and accommodation." In additoin, the Xi administration restructured the existing foreign affairs and national security systems. Establishing the Central State Security Committee and the Internet Leading Small Group (LSG) are cases in point. As comprehensive organizations for policy coordination that encompass party, government, and military, the two LSGs are in charge of enacting related policies and fine-tuning policy implementation, based upon leadership consisting of chiefs of each relevant organs. Moreover, since Xi himself became the chief of these two newly-found organs, the conditions under which these LSGs could demonstrate unified leadership and adjusting role in its implementation of military, diplomatic, and security policies were developed. The future Chinese diplomacy will be characterized with three main trends. First, peripheral diplomacy will be reinforced. The peripheral diplomacy has become far more important since the Work Conference on Peripheral Diplomacy in October 2013. Second, economic diplomacy will be strengthened with an eye on reducing the "China Threat Theory," which still exists in Asia. Third, the policies to isolate the Philippines and Japan will continue in regard to maritime disputes. All in all, Chinese diplomacy in the Xi Jinping era is likely to feature practical diplomacy which combines both hard and soft approaches to best realize Chinese national interest.

Interdomain Signaling in Stem Cell Maintenance of Plant Shoot Meristems

  • Bleckmann, Andrea;Simon, Rudiger
    • Molecules and Cells
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    • v.27 no.6
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    • pp.615-620
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    • 2009
  • The plant shoot meristem maintains a group of stem cells that remain active throughout the plant life. They continuously generate new cells that are then recruited for organ initiation in the peripheral zone. Stem cell proliferation and daughter cell differentiation has to be integrated with overall growth and development of the diverse functional domains within the shoot apex. Several studies have revealed extensive communication between these domains. The signaling mechanisms employed comprise diffusible peptides, directional transport of plant hormones, but also complex interactions between transcription factors, that together establish a panoply of regulatory inputs that fine-tune stem cell behavior in the shoot meristem.

Histologic Change of Free Muscle Graft in the Rabbit Pleural Space (토끼에서 늑막강내 자유근육이식의 조직학적 변화: 술후 공기누출방지를 위한 자유근육이식술의 예비실험)

  • 원용순
    • Journal of Chest Surgery
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    • v.22 no.1
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    • pp.10-15
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    • 1989
  • Excision of bullous emphysema or decortication of chronic empyema commonly results in a prolonged air leakage. Prolonged air leakage requires prolonged intercostal drainage, delays recovery, and can be followed complications such as pneumothorax, atelectasis, incomplete expansion of remained lung, secondary infection. To minimize these complications free muscle grafts can be used like a patch to close the opening of visceral pleura and reinforce suture lines without undue tension. From a preliminary study using the latissimus dorsi muscle as a free muscle graft in the rabbit pleural space, viable muscle fibers that seems the result of the process of regeneration can be consistently identified around the degenerating muscle fibers. Voluminous connective tissues and numerous blood vessels are also observed in the peripheral zone. Further studies in that free muscle graft will be sutured with visceral pleura and lung parenchyme will hopefully provide additional information before clinical application.

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Pathological findings of lymphocystis in cultured flounders (양식넙치에 발생한 lymphocystis의 병리학적 소견)

  • Kim, Soon-bok
    • Korean Journal of Veterinary Research
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    • v.40 no.2
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    • pp.333-337
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    • 2000
  • This experiment was done to observe the pathological findings of lymphocystis naturally occurred in the cultured flounders in the southern sea of Korea. Anatomical sign of lymphocystis was characterized by the presence of wart-like nodules on the fins, body surface and mouth. Dense clustering of hypertrophic cells originated from fibroblasts was observed in the lesions. Infected hypertrophic cells had a thick hyaline capsule, large vesiculated nucleus with irregular rims and large nucleolus, and large ribbon-shaped basophilic inclusions at the peripheral zone of the cytoplasm. Hexagonal virus particles with the two layers of capsid were scattered throughout the cytoplasm and were absent from the inclusions.

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An ultra-long-life small safe fast reactor core concept having heterogeneous driver-blanket fuel assemblies

  • Choi, Kyu Jung;Jo, Yeonguk;Hong, Ser Gi
    • Nuclear Engineering and Technology
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    • v.53 no.11
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    • pp.3517-3527
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    • 2021
  • New 80-MW (electric) ultra-long-life sodium cooled fast reactor core having inherent safety characteristics is designed with heterogeneous fuel assemblies comprised of driver and blanket fuel rods. Several options using upper sodium plenum and SSFZ (Special Sodium Flowing Zone) for reducing sodium void reactivity are neutronically analyzed in this core concept in order to improve the inherent safety of the core. The SSFZ allowing the coolant flow from the peripheral fuel assemblies increases the neutron leakage under coolant expansion or voiding. The Monte Carlo calculations were used to design the cores and analyze their physics characteristics with heterogeneous models. The results of the design and analyses show that the final core design option has a small burnup reactivity swing of 618 pcm over ~54 EFPYs cycle length and a very small sodium void worth of ~35pcm at EOC (End of Cycle), which leads to the satisfaction of all the conditions for inherent safety with large margin based on the quasi-static reactivity balance analysis under ATWS (Anticipated Transient Without Scram).

The Overview of Layered structures in Mafic - Ultramafic Macheon Intrusion (고철질-초고철질 마천관입암의 층상구조 개관)

  • Song, Yong-Sun;Kim, Dong-Yeon;Park, Kye-Hun
    • The Journal of the Petrological Society of Korea
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    • v.16 no.3
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    • pp.162-179
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    • 2007
  • Macheon Layered Intrusion (MLI) which intruded into Precambrian gneiss complex of the northern Jirisan area, southeastern part of Youngnam (or Sobaeksan) Massif, is a layered mafic-ultramafic complex of Triassic age (ca. 223 Ma). The MLI is divided into Layered Series and Laminated Series. Layered Series is subdivided into Central Zone (Lower Zone) consisting of olivine gabbros and Peripheral Zone (Middle or Upper Zone) consisting of hornblende gabbros based on the type of cumulus texture and the main mafic phase. The Central Zone of Layered Series comprises thinly laminated olivine gabbros and uniform or thickly laminated coarse olivine gabbros which consist of mela-gabbro, troctolite, leuco-troctolite, and anorthositic rocks. Laminated Series is also subdivided into quartz-bearing biotite-pyroxene gabbros and homblende diorite and both have variable amount of interstitial quartz and microcline. Laminated series display moderately to slightly developed igneous lamination which is defined by the planar alignment of lath-shape plagioclases. Chilled margin of quartz-bearing biotite-pyroxene gabbro with surrounding Precambrian gneisses insists shallower intrusion of more felsic cognate magma evolved in the deep a little later. Rocks of Layered Series have orthocumulus to adcumulus olivine, adcumulus to intercumulus plagioclase, and intercumulus to heteradcumulus pyroxene and hornblende. Magmatic modally grading, folding, and cross-lamination are not rarely occurred in thinly layered rocks. These textural characteristics define main mechanisms of the formation of layered and laminated structure in mafic-ultramafic rocks of Macheon Layered Intrusion are gravity settling and in-situ crystallization associated with slumping and density current.

Head Thrust Test (두부충동 검사)

  • Choi, Kwang-Dong;Oh, Sun-Young;Kim, Ji Soo
    • Annals of Clinical Neurophysiology
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    • v.8 no.1
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    • pp.1-5
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    • 2006
  • The head thrust maneuver is a simple bedside test of the higher frequency vestibulo-ocular reflex, which is based on Ewald's second law. It is performed by grasping the patient's head and applying a brief, small-amplitude, high-acceleration head turn, first to one side and then to the other. The patient fixates on the examiner's nose and the examiner watches for corrective rapid eye movements (saccades), which are a sign of decreased vestibular response. The "catch-up" saccades after a head thrust in one direction indicate a peripheral vestibular lesion on that side (in the labyrinth or the $8^{th}$ nerve including the root's entry zone in the brain stem). An individual pair of vertical semicircular canals can also be stimulated by turning the head to the right or left by $45^{\circ}$ and then by rotating the head in the pitch plane relative to the body. Recent studies have suggested that assessment of individual semicircular canal function by head thrust test may provide useful information for anatomical and functional details of a variety of peripheral vestibulopathies and for predicting the prognosis of vestibular neuritis. In central vestibulopathy, the head thrust test may also be valuable sign to determine dysfunction of the central pathways from individual semicircular canals and its role for the development of diverse central nystagmus.

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