• Journal of The Korean Astronomical Society
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• v.21 no.2
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• pp.105-116
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• 1988

We have investigated hydrodynamical behaviors of spicules by solving numerically the hydrodynamic equations subject to proper boundary conditions using the method of characteristics. We examined the behaviors of MHD slow mode waves propagating through rigid magnetic flux tubes which were excited by the pressure perturbations at the lower boundary. It is found that the spicules are identified as the manifestation of the movement of the transition region being pushed upward by collisions with the shock waves. One of the most important findings is the presence of the rebound shocks and their roles. We interpreted the rebound shocks in terms of the observed recurrent spicules.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.212-223
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• 2021

This study has purposes : evaluating how safe the skin is when applied with the Spicules-containing cosmetic, and whether Diamond-spicules is permeated into the skin and showed the efficacy of the active ingredients well. For these aims, women in their 30s and 60s were surveyed for skin irritation and changes after applying cosmetics to their skin for four weeks. As a result, Spicules-containing cosmetics were safer on the skin than general functional cosmetics, and in particular, in the case of cosmetics containing Diamond-spicules, statistically significant results (p<.001) were obtained in improvement of anti-wrinkle, firmness, moisturizing, whitening, alleviation of inflammation, and sensitivity. Thus, It has been proved Diamond-spicules containing functional active ingredients, not only as transdermal delivery system, but also can be used as multifunctional cosmetic material.

• Animal Systematics, Evolution and Diversity
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• v.26 no.1
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• pp.79-82
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• 2010

new species Iotrochota rutzleri n. sp. (Demospongiae: Poecilosclerida: Iotrochotidae) was collected from intertidal zone, Sinyangri, Seongsanpo, Jejudo Island, Korea during 2008-2009. Iotrochota rutzleri n. sp. is similar to I. baculifera Ridley, 1884 in composition of spicules and skeletal structure. However, it is different in size of spicules, growth form and colour. All spicules of this new species are smaller than those of the latter.

• Journal of Species Research
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• v.5 no.1
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• pp.31-48
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• 2016

Twelve new species of two genera Smenospongia and Cacospongia (Demospongia: Dictyoceratida: Thorectidae) are described from Gageodo Island and Ulleungdo Island, Korea. Of these, ten new species of the Smenospongia are distinguished from the other nine reported species of the genus by the skeletal structure and sponge colour. Primary fibres of the genus Smenospongia are mostly dense, dark colour, and invisible inside of fibres, but they are mostly cored detritus and echinated with spicules. Especially, the end of primary fibres at the surface shows densely cored with spicules. All these new species changed the colour. Two new species of the genus Cacospongia are compared with nine other reported species. In skeletal structure, primary fibres of the genus Cacospongia are light colour, visible inside and more heavily cored with spicules and sands. The skeleton of this genus has large meshes. The colour of the genus Cacospongia does not change.

• Journal of The Korean Astronomical Society
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• v.41 no.6
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• pp.173-180
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• 2008

Using the MHD coronal seismology technique, we estimated the magnetic field for three spicules observed in 2008 June. For this study, we used the high resolution Ca II H line ($3968.5\;{\AA}$) images observed by the Hinode SOT and considered a vertical thin flux tube as a spicule model. To our knowledge, this is the first attempt to estimate the spicule magnetic field using the Hinode observation. From the observed oscillation properties, we determined the periods, amplitudes, minimum wavelengths, and wave speeds. We interpreted the observed oscillations as MHD kink waves propagating through a vertical thin flux tube embedded in a uniform field environment. Then we estimated spicule magnetic field assuming spicule densities. Major results from this study are as follows : (1) we observed three oscillating spicules having durations of 5-7 minutes, oscillating periods of 2-3 minutes, and transverse displacements of 700-1000 km. (2) The estimated magnetic field in spicules is about 10-18 G for lower density limit and about 43-76 G for upper density limit. (3) In this analysis, we can estimate the minimum wavelength of the oscillations, such as 60000 km, 56000 km, and 45000 km. This may be due to the much longer wavelength comparing with the height of spicules. (4) In the first event occurred on 2008 June 03, the oscillation existed during limited time (about 250 s). This means that the oscillation may be triggered by an impulsive mechanism (like low atmospheric reconnection), not continuous. Being compared with the ground-based observations of spicule oscillations, our observation indicates quite different one, i.e., more than one order longer in wavelength, a factor of 3-4 larger in wave speed, and 2-3 times longer in period.

• The Korean Journal of Zoology
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• v.3 no.2
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• pp.1-4
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• 1960

Urticating spicules and poison -secreting cells of the last instar larva in Euproctis flava BREMER was studied histologically. Three kinds of cells in the epidermis of tubercles on the lst to 8th abodominal segments are classified according to the arrangement of their nuclei : smallepidermal cells, large gland cells, and elongated trichogen cells. As a result of Mallory's triple straining , the epicuticle , the papila-like structure apart form the tubules inside which are gathered at the base and connected with a middle layer cell through a canal in the cuticle, and the peripheral of the urticating spcicule are yellow. However, the inside of the spicule , the tubules within the papilla-like structure, the canal in the cuticle , nuclei in the pidermal cells and the thin exocuticle are red although the thich endocuticle is blue. Particularly , the large nuclei in the middle layer cells are bright red, the cytoplasms of which are little and stained red, too, and the inside of the spicules apt to be stained red when they are broken. The contents therefore seem to be continuous between the spicules and the large cells. Presumably , the large cell at the middle layer is not te tormogen cell which Tsutsumi (1958) has described , but the gland cell which secretes the poison-substance into spicules as Pawlowsky and Stein 91927) and Tonkes (1933) pointed out. Whether the pisonous substance is secreted from the gland cell into the cytoplasmic processes of the trichogen cells which stick large middle layer cells during the formation of the new spicule as Tsutsumi (1958) has observed, or the gland cell makes a new connection with the spicule after the spicule is formed is not clear.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.111-122
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• 2005

A study on marine sponges was conducted by SCUBA diving at Ulleungdo Island and Gageodo Island, Korea during the period from July 2000 to October 2001. Two species, Clathria (Clathria) gombawuiensis n. sp. and Clathria (C) gageoensis n. sp., are new to the fauna of sponges. Clathria (C) gombawuiensis n. sp. closely relates to Clathria (C) conica Levi, 1963 based on the type of spicules, but differs in size of spicules and growth form, Clathria (C) conica has not small toxa. Clathria (C) gageoensis n. sp. is similar to Clathria (C) hexagonopora Levi, 1963, but it differs in size of spicules and growth form, also Clathria (C) hexagonopora has not small toxa.

• The Bulletin of The Korean Astronomical Society
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• v.13
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• pp.7.1-7.1
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• 1988

• Animal Systematics, Evolution and Diversity
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• v.31 no.3
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• pp.141-145
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• 2015

A new marine sponge, Antho (Acarnia) seogwipoensis n. sp., of the family Microcionidae, was collected from Seogwipo-si, Jeju-do, Korea, about 100 m in depth using a gill net on 1969. The genus Antho Gray, 1867 including Demospongiae, Poecilosclerida, Microcionidae, is a large group of sponges. About 100 species in Antho were reported from worldwide. The genus Antho contains five subgenera: Antho, Acarnia, Isopenectya, Jia, and Plocamia. Among them, about 30 species in Acarnia were described in world sponge. A new sponge's body shape is branching, size up to 124 mm wide, 213 mm high, 3-8 mm thick in branch and 7-9 mm thick in stalk. Antho (Acarnia) seogwipoensis n. sp. is similar to A. (A.) novizelanicum Ridley and Duncan, 1881 based on their spicules type and skeletal structure, but differs in the spicules dimension and growth form. This new species is branched growth form and have three kinds of toxa.

• Animal cells and systems
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• v.12 no.1
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• pp.53-59
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• 2008

Two new marine sponges, Clathria(Clthria) gimnyeoungenesis n. sp. and Clathria(Clthria) reticularis n. sp., were collected in Jejudo Island, Korea by fishing nets in September 1994. C.(C.) gimnyeoungenesis n. sp. is closely related to C.(C.) toxipraedita Topsent, 1913 based on spicule types, but are different in the size of spicules and growth forms. Especially, the thick styles and large toxas length of this species are half of C.(C.) toxipraedita. Growth form of the new species is branched but massive encrusting in C.(C.) toxipraedita. C.(C.) reticularis n. sp. is similar to C.(C.) compressa Schmidt, 1862 based on spicule types, but are different in the size of spicules. Especially, large toxas of this new species is twice as long as C.(C.) compressa and they have large isochelae, which are absent in the latter.