• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.191-201
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• 2002

The first zoeal stage of Heptacarpus rectirostris (Stimpson, 1860) is re-described and illustrated in detail from laboratory-hatched material. The first zoea of H. rectirostris is more closely related to that of H. futilirostris than to H. camtschaticus, H. pandaloides, and H. geniculatus by having the pterygostomial spine and two anteroventral denticles on the carapace. The former two species, however, can be readily distinguished by the presence (H. futilirostris) or absence (H. rectirostris) of the posterolateral spine on the abdominal somites 4-5. A provisional key to the first zoeas of Heptacarpus for which larval studies are known from Korea and adjacent waters is provided. A list of larval descriptions within the Hippolytidae from Korea and adjacent waters is also included.

• Korean Journal of Clinical Pharmacy
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• v.21 no.2
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• pp.49-56
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• 2011

The family of bile acids belongs to a group of molecular species of acidic steroids with very peculiar biological characteristics. They are synthesized by the liver from cholesterol through several complementary pathways and secreted into small intestine for the participation in the digestion and absorption of fat. The bile acids are mostly confined to the territories of the so-called enterohepatic circulation, which includes the liver, the biliary tree, the intestine and the portal blood with which bile acids are returned to the liver. In patients with bile acid malabsorption, the amount of primary bile acids in the colon is increased compared to healthy controls. Although the increase in the secondary bile acids including deoxycholic acid, is reported to have the potency to affect tumorigenesis in gastrointestinal tracts, there is no firm evidence that clinically relevant concentrations of the bile acids induce cancer. The list of their physiological roles, as well as that of the pathological processes is long and still not complete. There is no doubt that many new concepts, pharmaceutical tools and pharmacological uses of bile acids and their derivatives will emerge in the near future.

• Current Research on Agriculture and Life Sciences
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• v.32 no.1
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• pp.43-52
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• 2014

Reactive oxygen and nitrogen species (ROS and RNS, respectively) are messengers that carry signals to alter the redox state in order to activate plant responses and other physiological processes, such as differentiation, aging, senescence, and pathogen defense. Quite a large number of genes are involved in this signaling and lead to oxidative stress in plants. Although the role of ROS/RNS during stress conditions is well documented, a comprehensive list of genes and comparative study of these genes has not yet been completed. Accordingly, the in silico identification of oxidative stress-related genes was performed for soybeans and Arabidopsis. These genes were also studied in relation to multiple domain prediction. The presence of domains like dehydogenase and ATPase suggests that these genes are involved in various metabolic processes, as well as the transportation of ions under optimal environmental conditions. In addition to a sequence analysis, a phylogenetic analysis was also performed to identify orthologous pairs among the soybean and Arabidopsis oxidative stress-related genes based on neighbor joining. This study was also conducted with the objective of further understanding the complex molecular signaling mechanism in plants under various stress conditions.

• ALGAE
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• v.24 no.4
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• pp.185-193
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• 2009

Geothermal springs in India, formed as a result of volcanic or tectonic activities, are characterized by high temperature and relatively abundant reduced compounds. These thermal springs are inhabited by characteristic thermophilic organisms including cyanobacteria. Cyanobacteria are among the few organisms that can occupy high temperature aquatic environments including hot springs. In alkaline and neutral hot springs and streams flowing from them cyanobacteria can form thick colourful mats that exhibit banding patterns. The present investigation involves study of mat forming cyanobacterial flora from hot springs located in Bakreswar, West Bengal, India. The important species found are Synechococcus bigranulatus, S. lividus, Gloeocapsa gelatinosa, G. muralis, Phormidium laminosum, P. frigidum, Oscillatoria princes, O. fragilis, Lyngbya lutea, Pseudanabaena sp., Calothrix thermalis, and Fischerella thermalis. Their distribution pattern in relation to physico-chemical parameters of spring water has also been studied. Three cyanobacterial strains of the above mentioned list were grown in culture and their pigment content and nitrogen fixing capacity were also studied. Nitrogen fixing capacities of Calothrix thermalis, Nostoc sp. (isolated in culture) and Fischerella thermalis are 5.14, 0.29, and 2.60 n mole $C_2H_4/{\mu}g$ of Chl-${\alpha}$/hr respectively. Carotenoid : Chlorophyll-${\alpha}$ ratio of four mat samples collected from Kharkunda, Suryakunda, Dudhkunda and bathing pool are 2.45, 1.60, 1.48, and 1.34, respectively. Higher value of Carotenoid : Chlorophyll-${\alpha}$ ratio coincided with higher temperature.

• Nuclear Engineering and Technology
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• v.41 no.1
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• pp.39-52
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• 2009

Theory-based models and high performance simulations are briefly reviewed starting with atomistic methods, such as Electronic Structure calculations, Molecular Dynamics, and Monte Carlo, continuing with meso-scale methods, such as Dislocation Dynamics and Phase Field, and ending with continuum methods that include Finite Element and Finite Volume. Special attention is paid to relating thermo-mechanical and chemical properties of the fuel to reactor parameters. By inserting atomistic models of point defects into continuum thermo-chemical calculations, a model of oxygen diffusivity in $UO_{2+x}$ is developed and used to predict point defect concentrations, oxygen diffusivity, and fuel stoichiometry at various temperatures and oxygen pressures. The simulations of coupled heat transfer and species diffusion demonstrate that including the dependence of thermal conductivity and density on composition can lead to changes in the calculated centerline temperature and thermal expansion displacements that exceed 5%. A review of advanced nuclear fuel performance codes reveals that the many codes are too dedicated to specific fuel forms and make excessive use of empirical correlations in describing properties of materials. The paper ends with a review of international collaborations and a list of lessons learned that includes the importance of education in creating a large pool of experts to cover all necessary theoretical, experimental, and computational tasks.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.206-209
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• 2010

A specimen of Redigobius bikolanus (29.0 mm SL) belonging to the family Gobiidae was collected by a hand net from the estuary of Changgo-cheon (river) in Andeok-myeon, Jeju Island, Korea. This specimen was characterized by having 26 lateral line scales, 7 predorsal scales, 7 transverse scales, anterior oculoscapular canal, preopercular canal, and four black spots between origin of anal fin and lower origin of caudal fin. The morphological characteristics of the specimen well matched those of Redigobius bikolanus previously reported. Thus, we newly add this species to the list of Korean fish fauna and propose its new Korean name, "Jeom-bak-i-mang-duk".

• The Korean Journal of Mycology
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• v.6 no.1
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• pp.43-47
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• 1978

Some 50 fungi were collected and identified at Youngu and Mt. Sobaek from April to October in 1977. The results have shown that, following ten species are new to Korean list. Collybia dryophila (BULL. ex FR.), QUEL., Mycena polygramma (BULL. ex FR.) S.F. GRAY., M. pura (PERS. ex FR.) QUEL., Crepidotus nephrodes (BERK. et CURT.) SACC., lnocybe montana KOBAY., I. squamulosa KOBAY., Rhodophllus ater HONGO, R. violaceus (MURR.) SING., Leccinum aurantiacum (BULL.) S.F. GRAY., and Suillus aeruginascens (SECR.) SNELL. The authors wish to express our thanks to Asan Foundation for the financial support for a part of this research project.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.195-201
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• 2011

We present a list of Korean fungivorous Tenebrionidae associated with higher fungi (Basidiomycetes). Most fungivorous tenebrionids are associated with the order Aphyllophorales. A total of 31 Tenebrionid species (both adults and larvae) belonging to four tribes (Bolitophagini, Toxicini, Scaphidemini, and Diaperini) are presented in our checklist. Of these, 62 percent are obligate mycetobionts, In addition, 42 fungal hosts of fungivorous tenebrionids are presented. Both thetenebrionids and the fungal hosts reported here are found throughout Korea.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.224-229
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• 2013

Bromotopsentin (BSM) is a bisindole alkaloid compound, which is recognized as a metabolite of the marine sponge Spongosorites sp. In this study, the antioxidant activity of BSM was investigated. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, the trolox equivalent antioxidant capacity (TEAC) assay, the superoxide radical scavenging (NBT) assay, the lipid peroxidation and hydroxyl radical-induced DNA damage assays were carried out to evaluate the antioxidant activity of BSM. It was found that BSM had stronger scavenging activity on the stable free radical DPPH and superoxide radical than L-ascorbic acid with an $IC_{50}$ value of 62 and 64 ${\mu}M$, respectively. The TEAC value which indicated the total antioxidant capacity of BSM was about 0.8, which was also stronger than L-ascorbic acid. About 1.3 ${\mu}M$ of BSM induced 50% inhibition of lipid peroxidation. 60 nM of BSM exhibited a significant protective activity against DNA strand scission by hydroxyl radical on pBR322 DNA. Taken together, we suggest that BSM possesses strong antioxidant activity, and could be a valuable new addition to the list of anti-aging chemotherapeutic agents.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.357-360
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• 2020

We identified Jolcham oak (Quercus serrata Thunb. ex Murray) (Fagales: Fagaceae) as a new host tree for Callipogon relictus Semenov (Coleoptera: Cerambycidae), a Korean natural monument and an endangered species, in Gwangneung Forest, South Korea. We herein report the morphometric characteristics of C. relictus larvae found in a Q. serrata tree and provide a revised list of C. relictus hosts.