• The Plant Pathology Journal
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• v.17 no.5
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• pp.305-307
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• 2001

In March 2000, gray mold was found on day lily (Hemerocallis fulva L.) in Korea. Among the symptoms observed was blight or early rot with chlorotic halo of the leaves. All the isolates obtained from the lesions of the diseased plant parts were identified as Botrytis elliptica, based on the morphological characteristics of conidia. Conidia that formed on conidiogenous cells were not in chains, hyaline to pale brown, unicellular, ellipsoidal to obovate with a single hilum at the base, entirely verruculose, and 21-31 x 12-$23\mu\textrm{m}$ in size. Pathogenicity of the fungus was established by artificial inoculation on day lily plants. This is the first record of gray mold on day lily caused by B. elliptica in Korea.

• ALGAE
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• v.20 no.4
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• pp.315-324
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• 2005

Anatomical organization of Stoechospermum marginatum reveals small cortical cells with moderately dense cytoplasm, overlying a multilayered medulla comparatively poor in cytoplasmic contents. The anticlinal walls of cortical cells show local thickenings rich in alginic acids. Sori form on both thallus surfaces and show tetrasporangia, paraphyses and sterile-cells. The unicellular paraphyses are rich in sulphated polysaccharides whereas multicellular ones have abundance of not only polysaccharides, but also of vacuoles and phenols. The sterile-cells are modified cortical cells present on either side of the tetrasporangium and bear cytoplasmic strands towards soral cavity. Various stages of tetrasporogenesis are seen in a single sorus. The developing tetrasporangium shows a two layered wall, where the outer one is rich in alginic acid and inner has sulphated polysaccharides. An apical pad aids tetraspore release. Also involved in the release process are sterile-cells, paraphyses and polysaccharides.

• Journal of Fashion Business
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• v.11 no.1
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• pp.125-135
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• 2007

Each cotton fiber is a unicellular hair collected from the seed of cotton plant. The fiber contains many convolutions along its length. Mercer was the first to suggest caustic soda treatment of cotton in commercial application. Mercerization has been commercially used since Lowe's suggestion to endow cotton with increased strength and affinity for dyes with additional properties such as fabric touch or luster. In this study, cotton fabric specimens were mercerized to investigate the changes in physical and mechanical properties pertaining to the hand or touch of fabrics. Physical properties were measured using the KES(Kawabata Evaluation System).

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1081-1087
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• 2011

An internally radiating photobioreactor was applied for the production of astaxanthin using the unicellular green alga Haematococcus pluvialis. The cellular morphology of H. pluvialis was significantly affected by the intensity of irradiance of the photobioreactor. Small green cells were widespread under lower light intensity, whereas big reddish cells were predominant under high light intensity. For these reasons, growth reflected by cell number or dry weight varied markedly with light conditions. Even under internal illumination of the photobioreactor, light penetration was significantly decreased as algal cells grew. Therefore, we employed a multistage process by gradually increasing the internal illuminations for astaxanthin production. Our results revealed that a multistage process might be essential to the successful operation of a photobioreactor for astaxnthin production using H. pluvialis.

• Animal cells and systems
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• v.11 no.2
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• pp.155-160
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• 2007

The skin of the Korean bullheads, Pseudobagrus brevicorpus and P. koreanus, is composed of epidermis, dermis and subcutis. The epidermis has three layers, the outermost layer, middle layer and stratum germinativum. The epidermis consists of two types of gland cells, an unicellular mucous cell of sulfomucin and a large club cell having sometimes two nuclei. The epidermis has numerous intraepithelial blood vessels in P. brevicorpus but not at all in P. koreanus. Lymphatic spaces containing lymphocytes are well developed in mainly the stratum germinativum. The dermis lacks scales and consists mostly of bundles of coarse collagen fibers. The collagen bundles are arranged in parallel to each other in the dorsum and lateral region toward the dorsum, but vertically at intervals in the abdomen and lateral region toward the abdomen. Considering this unique skin structure, the two species are likely to exercise cutaneous respiration as a dual respiratory system to overcome hypoxic conditions which frequently occurs in their habitats.

• ALGAE
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• v.20 no.1
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• pp.15-23
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• 2005

Polysiphonia pacifica is rhodomelaceous red algal species that includes five varieties in Pacific Ocean: P. pacifica var. delicatula, P. pacifica var. distans, P. pacifica var. determinata, P. pacifica var. disticha, and P. pacifica var. gracilis. We here report morphology and phylogeny of P. pacifica to confirm the relationships among previously described varieties as a loan of type specimens from US and to assess phylogenetic relationships of closely related species using plastid protein-coding rbcL gene. Polysiphonia pacifica is distinguished by having creeping filaments attached by unicellular rhizoids not cut off by cross walls, four pericentral cells, ecorticate, trichoblasts rare, ultimate branchlets attenuate at the tip but not pungent, and tetrasporangia in long straight series in the ultimate branchlets. The protein-coding plastid rbcL gene sequence data show that P. pacifica is distinctly different from the superficially similar species, P. morrowii and P. stricta. However, the rbcL sequences of P. pacifica var. pacifica and var. disticha are identical though they have morphological variation.

• ALGAE
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• v.31 no.2
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• pp.85-90
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• 2016

It is shown by the heterogenous nature of Borzi’s description and illustrations that Hormotila mucigena Borzi, the generitype of Hormotila, should be redefined. Borzi’s original description and accompanying illustrations of Hormotila (constituting the protologue) correspond to a minimum of five distinct genera of green algae. Two distinct concepts of the genus have persisted over the years. The genus has become based on a combination of palmelloid and physiologically stressed forms of two of the component algae. Our understanding of the genus is further confused by the incorporation of unrelated unicellular and colonial coccoid forms. There are only one or two distinctive attributes that would allow the selection of any one of the five forms as representing the genus and species. One of Borzi’s original figures is proposed to redefine the original species of the genus, Hormotila mucigena.

• Mycobiology
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• v.29 no.4
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• pp.227-229
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• 2001

A gray mold disease occurred on Cryptotaenia japonica in Korea. All the isolates of Botrytis sp. from the lesions of the diseased plants were identified to be B. cinerea based on the morphological characteristics. Conidia formed on conidiogenous cells were not in chains, hyaline to pale brown, unicellular, ellipsoidal to obovate with a single hilum at the base, entirely verruculose, and $6.3-11.3{\sim}6.3-10.0{\mu}m$ in size. Pathogenicity of the fungus was proved by artificial inoculation on C. japonica. This is the first record of gray mold on C. japonica caused by B. cinerea in Korea.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.23-27
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• 2008

Self-splicing group I introns in tRNA anticodon loops have been found in diverse groups of bacteria. In this work, we identified $tRNA^{fMet}$ group I introns in six strains of marine Synechococcus elongatus. Introns with sizes around 280 bp were consistently obtained in all the strains tested. In a phylogenetic analysis using the nucleotide sequence determined in this study with other cyanobacterial $tRNA^{fMet}$ and $tRNA^{Leu}$ intron sequences, the Synechococcus sequence was grouped together with the sequences from other unicellular cyanobacterial strains. Interestingly, the phylogenetic tree inferred from the intronic sequences clearly separates the different tRNA introns, suggesting that each family has its own evolutionary history.

• Journal of the korean society of oceanography
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• v.31 no.1
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• pp.18-22
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• 1996

The effect of exogenous oxygen on hydrogen photoproduction was examined in the synchronously grown cells of marine Synechococcus sp. Miami BG 043511 under conditions of high cell density (0.6-0.8 mg chl-${\alpha}$ $ml^{-1}$) and high light intensity (1000 ${\mu}$E $m^{-2}$ $s^{-1}$). Hydrogen evolution after 20-h incubation did not decline under the initial oxygen concentrations up to 20%, but declined by half under 34% oxygen. 50% and 100% oxygen gas phase did not completely inhibit the hydrogen photoproduction during 40-h incubations. After 2-day pretreatment under 100% exogenous oxygen the hydrogen photoproduction capabilities were not irreversibly inhibited, which was demonstrated in the subsequent 9-day incubation under initial 0, 50 and even under 100% oxygen gas phase. This strain could be useful for developing a hydrogen photoproduction system under atmospheric oxygen concentration.