• Title/Summary/Keyword: Tapering

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Origin and Development of Fascicular Cambium in Hypocotyl of Eucommia ulmoides Seedlings (두충나무 유식물의 하배축에서의 유관속내 형성층의 기원 및 발생)

  • 강재선
    • Journal of Plant Biology
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    • v.36 no.3
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    • pp.275-279
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    • 1993
  • The early ontogeny of the vascular cambium in the hypocotyl of Eucommia ulmoides seedling was studied anatomically. In transverse view, the procambial cells repeated periclinal divisions and then gradually differentiated into vascular cambium; however, in the transectional plane, it was difficult to reveal the origin of cambial initials. In tangential view, the early procambial cells repeated periclinal divisions and then the procambium consisted of homogeneous short cells. Some cells in late procambium did not show transverse divisions, but elongated continuously. Thus, the procambium showed a heterogeneous structure: The long cells became fusiform initials with tapering end walls and the short cells differentiated into ray initials. Conclusively, the two types of cambial initials were gradually originated from the homogeneous cells at the early procambial stage, and they consisted vascular cambium.

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Preparation of Taper Table for Main Species (Korean White Pine) in Korea. (II) (주요수종(主要樹種)(잣나무)의 완만도표조제(完滿度表調製)(II))

  • Lee, Heung Kyun;Choi, Jong Cheon
    • Journal of Korean Society of Forest Science
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    • v.43 no.1
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    • pp.51-55
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    • 1979
  • This study discribes about method of establishing stem taper table of Korean white pine through the preparation of the stem with the sample trees of 280 felled Korean white pine. Stem curves were first classified then induced by form quotient class, stem curve equation according to Behre's stem curve formular. Relied on each calculated stem curve equation tapering degree by form quotient class and established taper table therefore.

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Two-Dimensional Analysis Model for Tapered Pulse Tubes (테이퍼를 갖는 맥동관의 2차원 해석모델)

  • Baek, Sang-Ho;Jeong, Eun-Soo
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.5
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    • pp.668-676
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    • 2000
  • A two-dimensional model for pulse tubes with tapered cross-section was proposed. Net enthalpy flow and steady mass streaming were investigated by two-dimensional analysis of mass, momentum and energy equations of the gas as well as energy conservation of the tube wall. Steady mass flux profiles show good agreement with the previous approximate solution. It was shown that steady mass streaming can be reduced by tapering a pulse tube and by increasing the length of a pulse tube. Effects of the velocity phase angle and frequency on steady mass streaming were shown.

Liquid Refractive Index Sensor Based on Cladded Plastic Optical Fiber Taper (클래딩이 있는 플라스틱 광섬유 테이퍼를 이용한 용액 굴절률 센서)

  • Kim, Kwang-Taek;Kim, Hoe-Man;Yun, Jung-Hyun
    • Journal of Sensor Science and Technology
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    • v.21 no.2
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    • pp.151-155
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    • 2012
  • We have investigated a refractive index sensor based on a cladded plastic optical fiber taper. The optical transmission and sensing characteristics of the device were illuminated in terms of ray optics. The sensor devices showed that the optical transmittance strongly depends on the refractive index of the external medium surrounding the tapered region.

Discernibly Temperature-insensitive Pressure Sensitivity in Porous Random-Hole Optical Fibers

  • Kim, Jeong;Kominsky, Dan;Pickrell, Gary
    • Journal of the Optical Society of Korea
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    • v.17 no.4
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    • pp.300-304
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    • 2013
  • Novel breakthrough random-hole optical fibers (RHOFs) are fabricated in a draw tower facility, by tapering an optical fiber preform packed with a silica powder mixture capable of producing air holes in situ at the high temperature of tens of hundreds in degrees Celsius. Structural and propagation characteristics of the porous RHOF are explained briefly. Experimental investigations of the invented RHOF are performed for pressure sensor applications. Remarkable results are obtained for the RHOF with desirable pressure sensitivity independent of temperature, as is required for harsh conditions as in oil reservoirs.

Diaporthe taoicola and D. siamensis, Two New Records on Citrus sinensis in China

  • Cui, Meng Jiao;Wei, Xin;Xia, Peng Liang;Yi, Ji Ping;Yu, Zhi He;Deng, Jian Xin;Li, Qi Li
    • Mycobiology
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    • v.49 no.3
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    • pp.267-274
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    • 2021
  • Two Diaporthe species isolated from fruit of Citrus sinensis in China were characterized based on morphology and multilocus phylogeny of ITS, tef1, and tub2 gene sequences. The phylogeny indicated that the two species match Diaporthe taoicola and D. siamensis. A critical examination of phenotypic characteristics confirmed the phylogenetic results. Diaporthe taoicola was morphologically characterized by producing Alpha conidia with tapering toward both ends. Meanwhile, D. siamensis produced cylindrical or ellipsoidal Alpha conidia with two oil drops. Pathogenicity tests revealed that both species were pathogenic to fruit of C. sinensis. To our knowledge, the two species were firstly reported on Citrus sinensis in China.

First Records of Two Cirolanid Species (Isopoda, Cymothooidea, Cirolanidae) from Korean Waters

  • Kim, Sung Hoon;Yoon, Seong Myeong
    • Animal Systematics, Evolution and Diversity
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    • v.35 no.4
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    • pp.168-181
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    • 2019
  • Two cirolanid isopods, Eurydice longiantennata Nunomura and Ikehara, 1985 and Metacirolana japonica (Hansen, 1890), are newly reported based on the materials collected from the subtidal zone around Jeju Island. Eurydice longiantennata can be distinguishable from its congeners by the following features: body length is 5 mm; antennule is not extending beyond the cephalon; flagellum of the antenna is consisted of 31 flagellar articles; and pleotelson has eleven teeth and twelve setae distally. Metacirolana japonica is distinguished from its related species by the following characteristics: body is not ornament; pleonite 1 is entirely visible dorsally in male; pleotelson is gradually tapering distally; and uropodal rami have serrate margins.

Correction of pixie ear: infraauricular skin redraping method

  • Kim, Jun Hyeok;Yang, Young Bin;Oh, Deuk Young
    • Archives of Craniofacial Surgery
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    • v.23 no.4
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    • pp.187-189
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    • 2022
  • Patients with pixie ear have an attached, tapering, and low-set earlobe. Traditional methods usually describe excision of the caudal portion of the lobule and reattachment in a more superior position. The present report suggests a simplified skin redraping method for correction of pixie ear. The procedure provides easy method to design and perform, which only requires elevation and trimming of the skin. Other ancillary procedures, such as flap design, anchoring, plication, and subdermal fixation, are not required. This method produces satisfactory results. Postoperative scar is invisible because the incision is on the retroauricular region, and the corrected earlobe has a more natural appearance than the repositioned earlobe. Moreover, skin redraping avoids tension, which contributes to minimization of the postoperative scar.

Polyposis of gastrointestinal tract after COVID-19 mRNA vaccination: a report of two cases

  • Jun Ho Kim;Eun Hye Oh;Dong Soo Han
    • Clinical Endoscopy
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    • v.57 no.3
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    • pp.402-406
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    • 2024
  • Cronkhite-Canada syndrome is a rare gastrointestinal polyposis syndrome with distinctive clinical features and endoscopic findings. Diagnosis can be challenging without suspicion, and the disease carries high mortality due to complications such as infection, gastrointestinal bleeding, and malignancies. This paper presents two cases of Cronkhite-Canada syndrome occurring after coronavirus disease 2019 (COVID-19) mRNA vaccination. Both cases exhibited typical clinical findings, including hypogeusia, onychodystrophy, alopecia, and weight loss. Typical polyposis in the gastrointestinal tract was confirmed through endoscopies. As symptomatic treatment did not improve the symptoms, corticosteroids were administered, and symptoms and laboratory test results improved immediately. The patients improved upon corticosteroids tapering. These cases illustrate typical presentations of Cronkhite-Canada syndrome and the course of the disease following corticosteroid treatment. Additionally, they suggest the possibility that Cronkhite-Canada syndrome may be triggered by COVID-19 mRNA vaccination.

A New Species of Arabella (Annelida, Polychaeta, Oenonidae) from Korean Waters

  • Seong Hun Kang;Yu Seok Jeong;Hyun Ki Choi;Seong Myeong Yoon
    • Animal Systematics, Evolution and Diversity
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    • v.40 no.3
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    • pp.157-166
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    • 2024
  • A new oenonid polychaete, Arabella turbidiricolor sp. nov., collected from intertidal zone along the coasts of eastern, western, and southern Korea is described. In Korea, this new species might have been confused with Arabella iricolor(Montagu, 1804), the type species of the genus, in having the following characteristics: ventralmost chaeta tapering gradually to guard, MI left robust and right gracile, MII right long, MV both with one tooth and posterior postchaetal lobe shorter than chaetae. However, A. turbidiricolor sp. nov. is readily distinguished from the latter by the following features: ventral maxillary carriers longer than or equal to dorsal, MI both distally falcate, and pygidium with two swollen pads. We provide detailed descriptions and illustrations for the new species in the present study. Also, morphological characteristics of known Arabella species are compared and discussed with a key to them.