• Journal of Microbiology and Biotechnology
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• 제25권8호
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• pp.1227-1233
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• 2015

Vascular endothelial growth factor (VEGF) plays a key role in angiogenesis through binding to its specific receptors, which mainly occurs to VEGF receptor 2 (VEGFR-2), a kinase insert domain-containing receptor. Therefore, the disruption of VEGFR-2 signaling provides a promising therapeutic approach for the treatment of cancer by inhibiting abnormal or tumorinduced angiogenesis. To explore this potential, we expressed the catalytic domain of VEGFR-2 (VEGFR-2-CD) as a soluble active kinase in Escherichia coli. The recombinant protein was purified and the VEGFR-2-CD activity was investigated. The obtained VEGFR-2-CD showed autophosphorylation activity and phosphate transfer activity comparable to the commercial enzyme. Furthermore, the IC₅₀ value of known VEGFR-2 inhibitor was determined using the purified VEGFR-2-CD. These results indicated a possibility for functional and economical VEGFR-2-CD expression in E. coli to use for inhibitor screening.

• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.848-855
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• 2020

Land subsidence induced by underground coal mining leads to severe ecological and environmental problems. Arbuscular mycorrhizal fungi (AMF) have the potential to improve plant growth and soil properties. We aimed to assess the effects of AMF on the growth and soil properties of sea buckthorn under field conditions at different reclamation times. Inoculation with AMF significantly promoted the survival rate of sea buckthorn over a 50-month period, while also increasing plant height after 14, 26, and 50 months. Crown width after 14 months and ground diameter after 50 months of inoculation treatment were significantly higher than in the uninoculated treatment. AMF inoculation significantly improved plant mycorrhizal colonization rate and promoted an increase in mycelial density in the rhizosphere soil. The pH and electrical conductivity of rhizosphere soil also increased after inoculation. Moreover, after 26 and 50 months the soil organic matter in the inoculation treatment was significantly higher than in the control. The number of inoculated soil rhizosphere microorganisms, as well as acid phosphatase activity, also increased. AMF inoculation may play an active role in promoting plant growth and improving soil quality in the long term and is conducive to the rapid ecological restoration of damaged mining areas.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.784-788
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• 2007

Growth hormone-releasing hormone (GHRH), a hypothalamic neuropeptide can stimulate the growth hormone secretion from the anterior pituitary. In this study, a porcine GHRH expression plasmid pHC-GHRH was used to enhance growth performance through ectopic expressions in muscle tissues of rats. Rats injected with the plasmid of pHC-GHRH and pCMV-GHRH exhibited cumulative weight gains 6.4% and 1% greater than controls. During a 5-day period, significant weight gain differences were observed as follows compared with that of control: during 5-10 days post-injection (DPI) period, the group pHC-GHRH on average 14.5% heavier than controls, $40.73{\pm}0.88$ g vs. $35.57{\pm}1.23$ g (p = 0.0023); during 10-15 DPI period, the group pHC-GHRH on average 13.6% heavier than controls, $37.49{\pm}2.85$ g vs. $33.00{\pm}1.56$ g (p = 0.0146); during 15-20 DPI period, the group pHC-GHRH on average 17.8% heavier than controls, $25.64{\pm}1.39$ g vs. $21.77{\pm}1.27$ g (p<0.05). In addition, plasmids-treated rats maintained higher serum IGF-I than controls. Significant differences of IGF-I were observed on 13 DPI and on 40 DPI in pHC-GHRH group compared with that of controls. This was accomplished through the use of an improved expression cassette that included the cytomegalovirus (CMV) immediate early enhancer/promoter in combination with a 1.5-kilobase portion of porcine ${\alpha}$-skeletal muscle actin promoter.

• 원예과학기술지
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• 제31권4호
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• pp.393-399
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• 2013

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures ($15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$) within a natural aerial temperature ($15-30^{\circ}C$). Four nitrate:ammonium ($NO{_3}^-:NH{_4}^+$) ratios (10:0, 8:2, 5:5, and 2:8 $mmol{\cdot}L^{-1}$) at constant nitrogen (N) concentration of $10mmol{\cdot}L^{-1}$ were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 $NO{_3}^-:NH{_4}^+$ ratio in the $15^{\circ}C$ solution, the 5:5 ratio in the $20^{\circ}C$ solution and the 8:2 ratio in the $25^{\circ}C$ solution. Photosynthetic rate (Pn) response to solution temperature and $NO{_3}^-:NH{_4}^+$ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

• Fisheries and Aquatic Sciences
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• 제26권10호
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• pp.583-592
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• 2023

Celebes rainbow (Marosantherina ladigesi) is one of Indonesia's exported ornamental fish commodities, but the exploitation of this fish only relies on wild catches. The rise of unlimited fishing, especially those using poison, has changed the aquatic environment, threatening sustainability and causing fish extinction. This study aimed to evaluate the effectiveness of several types of feed in improving the absolute growth rate (AGR), specific growth rate (SGR), survival rate (SR), feed conversion ratio (FCR), feed efficiency (FE), hematology, and immune response of Celebes rainbow. The fish used in this study were male ornamental Celebes rainbow (M. ladigesi) weighing 1.32 ± 0.21 g/ind, reared in 54 L-aquariums at a stocking density of 30 individuals/aquarium for six weeks. The fish were fed according to the test diet consisting of live Tubifex sp worms, dry Tubifex sp worms, Spirulina platensis, and crumble pellets. The parameters observed were AGR, SGR, SR, FCR, FE, hematology, intestinal histology, liver histology, and a challenge test with the pathogenic bacteria Aeromonas hydrophila. The results showed that fish-fed live Tubifex sp worms had better AGR, SGR, SR, FCR, FE, hematology, and disease resistance compared to all other treatments. These results indicate that live Tubifex sp worms are the best feed for rearing Celebes rainbow.

• 한국수산과학회지
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• 제55권6호
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• pp.894-902
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• 2022

This study investigated the effects of photoperiod (NL 12L:12D and LL 24L:0D) and body sizes (30 g and 50 g) on parr-smolt transformation, post-smolt growth and blood properties in the off-season parr-smolt stage of Atlantic salmon reared in a recirculating aquaculture system (RAS). Potential off-season salmon smolt were reared in a freshwater RAS for 80 days and then all experimental fish were transferred to seawater. In both LL groups (LL-30 and LL-50), we recorded and increase in specific growth rate and reduction in feed conversion, although there were no significant difference in body size. The values of osmolality, and serum Na⁺, Cl^- and cortisol concentrations in the LL groups were maintained at lower levels than in NL group fish, and LL group fish were observed to recover to the pre-seawater adaptation state more rapidly than those in the NL group. ID chips were inserted in all smolts reared in freshwater. These fish were subsequently transferred to full-strength seawater and thereafter individual growth rates were monitored for 120 days. The results indicated that compared with smolt reared under natural photoperiodic condition, 24 h lighting in freshwater contributed to enhancing post-smolt specific growth rate in seawater.

• Journal of applied mathematics & informatics
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• 제31권3_4호
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• pp.385-398
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• 2013

In this paper, a turbidostat model with ratio-dependent growth rate and impulsive state feedback control is considered. We obtain sufficient conditions of the globally asymptotically stable of the system without impulsive state feedback control. We also obtain that the system with impulsive state feedback control has periodic solution of order one. Sufficient conditions for existence and stability of periodic solution of order one are given. In some cases, it is possible that the system exists periodic solution of order two. Our results show that the control measure is effective and reliable.

• Mycobiology
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• 제30권4호
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• pp.228-232
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• 2002

This study focused on the production of high quality compost for the growth of aero-thermophilic fungi, which has a promoting effect on the growth rate and production of oyster mushrooms. The automated solid-state bioreactor system was designed on the basis of a Three-Phase-One system, which controls the serial steps of prewetting, pasteurization and fermentation processes. High numbers of thermophilic fungi and bacteria were recovered from the mushroom composts prepared by this solid-state bioreactor. The rates of composting process were depended on physical as well as chemical factors. Among these factors, the parameters of moisture content and temperature were found to be particularly important. In our automated system, constant levels of moisture content, temperature and ventilation via mixing were provided by a centralized control apparatus including PLC, water tank and water jacket systems. These features induced higher microbiological activity of aero-thermophiles.

• 대한기계학회논문집B
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• 제24권6호
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• pp.792-801
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• 2000

The problem of phase change from liquid to solid in the inviscid plane-stagnation flow is theoretically investigated. The solution at the initial stage of freezing is obtained by expanding it in powers of time, and the final equilibrium state is determined from the steady-state governing equations. The transient solution is dependent on the three dimensionless parameters, but the equilibrium state is determined by one parameter of (temperature ratio/conductivity ratio). The effect of the fluid flow on the growth rate of the solid in the pure conduction problem can be clearly seen from the solution of the initial stage and the final equilibrium state. The characteristics of the transient heat transfer at the surface of the solid and the liquid side of the solid-liquid interface for all the dimensionless parameters are elucidated.

• Architectural research
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• 제15권2호
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• pp.59-68
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• 2013

To ameliorate a long-standing, persistent housing shortage in Korea, large-scale massive housing production has been an imperative, and the extensive growth highly values development and consumption. The state's priority for the quantitative growth of housing stock has proved to be successful, but the state faces with economic and environmental crises in a global era. To achieve the qualitative growth, the previous administration pronounced a green growth policy from the inception, and a series of strategic measures under a holistic plan have been taken widely and vigorously. As part of the strategies, the green home project was undertaken, and simultaneously the movement of green living led by the governance has been activated. However, little attention to the grassroots effort was paid and the efficacy hasn't been adequately addressed. This study examines the factors affecting green living of residents in multifamily housing. Based on public guidelines to green living, 106 specific items were drawn out and largely categorized into 6 areas (water, waste, transportation, air quality, consumption, and energy), and the questionnaire was constructed using them. Of 750 survey forms mailed out, 161 responses were returned and the collected data were used for statistical analysis. The findings indicated that varying degrees of green living was well practiced, the state-led green home project was relatively well recognized, and the green growth policy was strongly supported. Also the respondents' attitude toward green living were more associated with demographic variables than housing characteristics, and familiarity with green home project was related to attitudes toward green living. Since the on-going approach to green living has focused on simple and economical ways, it has proved to be effective but progressive strategies to make living greener are necessarily developed.