• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.375-381
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• 2013

A freshwater microalga, Chlamydomonas reinhardtii KNUA021, was characterized for its potential as a biochemical feedstock. Its optimal growth was observed when the culture was incubated at $25^{\circ}C$ and pH 9.4. However, the isolate was capable of survival and growth under a variety of temperatures (10-$30^{\circ}C$) and pH (pH 4.0-12.0) conditions. The total lipid content of the isolate was 21.7% of dry weight and it was found that a high-value fatty alcohol, hexadecenol ($C_{20}H_{40}O$), was autotrophically produced by strain KNUA021. In addition, a nutritionally important $C_{18:3}{\omega}3$ (${\alpha}$-linolenic acid, ALA) was also identified in this photosynthetic microorganism as one of the major fatty acids. Hence, C. reinhardtii KNUA021 appears to show promise for use in the production of microalgae-based biochemicals.

• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.39-47
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• 1980

The harvesting and export of Canadian ginseng from the cool, shady hardwood forests of southern Canada can be traced to 1796. Because of its high dollar value and diminishing woodland supplies it was decided in 1896 that it should be cultivated under wood lath screens. Present day economics dictate changes in production techniques to allow for a decreasing supply of expensive labour. Traditional wooden lath screens have a surface area of wood of 70 per cent and permit light penetration of only about 18 per cent. Experimental woven black polypropylene shade has an estimated surface area of 72 per cent and permits light pentration of about 28 per cent. While differences in air and leaf temperatures under the two shade structures can be measured it is doubtful if these are great enough to cause differences in plant growth under the two structures. Shade grown ginseng had a low fresh and dry weight and total chlorophyll content (ratio of a to b was 3 to 1) comparable to other shade species. There was no differences in fresh and dry weight and chlorophyll content of leaves from plants grown under the two shade structures. Maximum net photosynthesis of leaves was 0.175 g $CO_2\;m^{-2}\;hr^{-1}$ and light saturation level was about $200{\mu}E\;m^{-2}\;s^{-1},$ or about 10 per cent of full sunlight.

• Development and Reproduction
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• v.24 no.3
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• pp.225-230
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• 2020

This study reports the presence of mature and bi-sexual phase gonads in red spotted grouper, Epinephelus akaara after less than a year of cultivation in a commercial indoor tank and a net cage. In December 2018, juveniles were placed in an indoor tank and cultured for five months. In June 2019, the fish were transferred to a net cage and cultured until September. The rearing temperatures ranged from 19.86℃-24.65℃ in the indoor tank and 21.86℃-27.65℃ in the net cage. During the net cage culture period, specimens were randomly selected for histological gonad examination. The highest gonadosomatic index (GSI) value was measured in July (3.38±2.53), and dramatically decreased in August (0.44±0.21) and September (0.42±0.30). In July, some mature fish showed signs of vitellogenic stage oocyte development (vitellogenic and oil droplet stage oocytes), but immature fish were in an early developmental stage containing peri-nucleolus stage (PNS) oocytes. Bi-sexual phase gonads containing spermatocytes and spermatids were observed in the lumen and several PNS oocytes. By August and September, most specimens showed early-stage ovary development. However, mature testis (in August) and bi-sexual phase gonads (in September) were also observed. These results provide evidence for early puberty and hermaphroditism in the red spotted grouper.

• Journal of Microbiology
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• v.37 no.4
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• pp.200-205
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• 1999

7-Aminocephalosporanic acid (7-ACA) is the initial compound in preparation of cephalosporin antibiotics widely used in clinical treatment. Bacteria producing glutaryl 7-ACA acylase, which convert cephalosporin C to 7-ACA, has been screened in soil samples. A bacterial strain exhibiting high glutaryl 7-ACA acylase activity, designated KAC-1, was isolated and identified as a strain of Pseudomonas diminuta by characterizing its morphological and physiological properties. The screening procedures include culturing on enrichment media containing glutaric acid, glutamate, and glutaryl 7-aminocephalosporanic acid as selective carbon sources. To enhance enzyme production, optimal cultivation conditions were investigated. This strain grew optimally at pH 7 to 9 and in temperatures of 20 to 40 C, but acylase production was higher when the strain was grown at 25 C. Glutaric acid, glutamate and glucos also acted as inducers for acylase production. In a jar fermenter culture, P. diminuta KAC-1 produce acylase in a growth-associated manner. The substrate specificity of KAC-1 acylase by cell extract showed that this enzyme had specificity toward glutaryl 7-ACA, glutaryl 7-ADCA, but not cephalosporin C.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.1
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• pp.59-66
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• 2019

The growth and maturation pattern of a commercial and endemic red algae Meristotheca papulosa were investigated in Jeju Island. Ecological researches were performed in a natural population of 10 m water depth in Sinheung from march 2014 to November 2015. Maximal blade length and weight of M. papulosa were 8.7 cm and 5.49 g in July 2014 and 10.7 cm and 10.17 g in September 2015, respectively. Growth in blade area of the species reached a maximum of $43.84cm^2$ and $67.41cm^2$ in July 2014 and 2015, respectively. Thalli in the field population were rarely observed from October to December but new recruits were found from January, following year. Carposporophytes were observed from June to September when bottom seawater temperatures were around $20^{\circ}C$. At the study site, seawater temperature was in the range of $14.9-25.7^{\circ}C$. Growth parameters of M. papulosa and relative abundance of carposporophytes showed significant correlation with environmental factors (temperature, salinity, DIN). In this result, we clarified the growth and maturation period of M. palpulosa, and provided effective data on the protection and management of natural populations and basic data for mass culture of the alga.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.2
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• pp.115-122
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• 2020

Eisenia bicyclis, a perennial macroalga is a primary producer of in the ocean, It has been identified as a key species that plays a vital role in maintaining the ecosystem stability. Also, it is an important target in marine afforestation projects and useful marine organisms. In addition, E. bicyclis is used as a health food for humans. This study investigated the effect of water temperature, light (photon irradiance), and duration of light (photoperiod) on the growth of gametophytes and young sporophytes of E. bicyclis. The germination and growth of the zoospores of E. bicyclis were examined at five temperatures (5℃, 10℃, 15℃, 20℃ and 25℃), four intensities of photon irradiance (10, 20, 40, and 80 μmol m-2s-1), and photoperiods (14:10 and 10:14 light/dark cycles). The zoospores released from mature plant germinated into the gametophytes under all experimental conditions. The gametophytes were able to grow at water temperature 5℃-25℃ and mature at 10℃-20℃. The optimal range of water temperature for the maturation of the gametophyte was 15℃-20℃. At 25℃, E. bicyclis gametophytes grew rapidly but did not mature. The optimal culture conditions for the growth of young sporophytes grew slowly in low temperature and photon irradiances.

• Fisheries and Aquatic Sciences
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• v.24 no.12
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• pp.400-405
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• 2021

In this study, the relationship between the growth of abalone and the presence of epibionts was investigated in abalone cultured in Goheung, Jeollanam-do, where there are severe problems high water temperatures and attachment. The experiment was conducted for eight months (May-December 2020), and 40 abalone were collected every month. Water temperature was at its highest at a range of 13.5℃-26.6℃ and dissolved oxygen levels were at their lowest at a range of 4.0-10.2 ㎍/L in August. The shell height (mm) of abalone grew to 117.7% (81.8 ± 1.9 mm) in cultures where epibionts were removed (ER) and 111% (77.4 ± 3.3 mm) where they were not (non-epibionts, NER). Their total weight (TW) and body weight increased significantly and steadily with ER, whereas the TW increased sharply after August with NER. In the condition index, no significant difference was observed between ER and NER. The monthly proportion of epibionts increased significantly in July, accounting for the value of 69.9% reached in December.

• Smart Structures and Systems
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• v.29 no.4
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• pp.561-576
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• 2022

Heritage timber structures represent the history and culture of a nation. These structures have been inherited from previous generations; however, they inevitably exhibit deterioration over time, potentially leading to structural deficiencies. Structural Health Monitoring (SHM) offers the potential to assess operational anomalies, deterioration, and damage through processing and analysis of data collected from transducers and sensors mounted on the structure. This paper reports on the design and implementation of a long-term SHM system on the Feiyun Wooden Pavilion in China, a three-story timber building built more than 500 years ago. The principles and features of the design and implementation of SHM systems for heritage timber buildings are systematically discussed. In total, 104 sensors of 6 different types are deployed on the structure to monitor the environmental effects and structural responses, including air temperature and humidity, wind speed and direction, structural temperatures, strain, inclination, and acceleration. In addition, integrated data acquisition and transmission subsystem using a newly developed software platform are implemented. Selected preliminary statistical and correlation analysis using one year of monitoring data are presented to demonstrate the condition assessment capability of the system based on the monitoring data.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.202-208
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• 2006

An experiment was conducted to investigate the effects of three water temperatures (15, 20 and $25^{\circ}C$) in combination with three salinities (0, 15 and 30 psu) on the oxygen consumption rate of juvenile spotted sea bass, Lateolabrax maculatus (mean body weight $5.5{\pm}0.3g$). The oxygen consumption rates of L. maculatus were measured in triplicate for 24 hours using a continuous flow-through respirometer. Water temperature resulted in significant differences in the mean oxygen consumption rate of L. maculatus (p<0.001), but salinity and combinations of salinity and water temperature did not have (p>0.05). The oxygen consumption increased with increasing water temperatures in all experimental salinity regimes (p<001). Mean oxygen consumption rates at 15, 20 and $25^{\circ}C$ ranged 328.8~342.3, 433.9~441.0 and 651.5~659.9 mg $O_2\;kg^{-1}\;h^{-1}$, respectively. $Q_{10}$ values did not vary with salinity, bud varied with water temperature. $Q_{10}$ values ranged 1.63~1.75 between 15 and $20^{\circ}C$, 2.24~2.26 between 20 and $25^{\circ}C$, and 1.92~1.98 over the full temperature range. The energy loss by metabolic cost increased with increasing water temperatures in all experimental salinity regimes (p<0.001) Mean energy loss rates at 15, 20 and $25^{\circ}C$ ranged 224.6~233.8, 296.3~301.2 and $444.9{\sim}450.7kJ\;kg^{-1}\;d^{-1}$, respectively. These data suggest that the culture of juvenile spotted sea bass is possible without energy loss by salinity difference in freshwater as well as seawater after salinity acclimation. Thus, this result has an application for culture management and bioenergetic model for growth of this species.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.228-241
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• 2021

Cremated archaeological bones provide crucial information to unravel the details of ancient cremation events and funeral culture. The research on cremated bones to date has been mainly focused on extracting archaeological information in Korea. Recently, the techniques of physical anthropology have been applied to obtain biological information and cremation temperatures for individuals. This study analyzed human remains excavated from Seoul Seokchon-dong Ancient Tombs and determined whether there were human cremations as well as the estimated cremation temperatures. There was no trace of fire in the pits where cremated bones were found; therefore, it is assumed that they were deposited with the artifacts. In this study, four samples were selected according to the surface color of the bones, and X-ray diffraction analysis (XRD) and Fourier-transformed infrared spectroscopy (FT-IR) were used for analysis. All four of the Seokchon-dong cremated bones were found, based on the crystallization index of X-ray diffraction analysis, to have experienced cremation above the temperature of 700℃. Infrared spectroscopy results indicated that the four bones from Seokchon-dong were cremated at temperatures above 700℃ and below 1,000℃. IR peaks were observed at 700℃, whereas no changes were found when bones experienced more than 1000℃. We assume that the cremated people in the Seokchon-dong Tombs were people of high-status because cremation at such a high temperature at that period required much effort. Here we present significant evidence of the cremation status and temperature of archaeological human bones on the basis of XRD and FT-IR, allowing for the restoration of the cremation events and funeral culture in archaeological sites.