• Journal of Bio-Environment Control
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• v.32 no.2
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• pp.148-156
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• 2023

This study was conducted in an indoor cultivation room and chamber where environmental control is possible to investigate the effect of temperature and irrigation interval on photosynthesis, growth and growth analysis of potted seedling cucumber. The light intensity (70 W·m^-2) and humidity (65%) were set to be the same. The experimental treatments were six combinations of three different temperatures, 15/10℃, 25/20℃, and 35/25℃, and two irrigation intervals, 100 mL per day (S) and 200 mL every 2 days (L). The treatments were named 15S, 15L, 25S, 25L, 35S, and 35L. Seedlings at 0.5 cm in height were planted in pots (volume:1 L) filled with sandy loam and treated for 21 days. Photosynthesis, transpiration rate and stomatal conductance at 14 days after treatment were highest in 25S. These were higher in S treatments with a shorter irrigation interval than L treatments. Total amount of irrigation water was supplied evenly at 2 L, but the soil moisture content was highest at 15S and lowest at 25S > 15L > 25L, 35S and 35L in that order. Humidity showed a similar trend at 15/10℃ (61.1%) and 25/20℃ (67.2%), but it was as high at 35/25℃ (80.5%). Cucumber growth (plant height, leaf length, leaf width, chlorophyll content, leaf area, fresh weight and dry weight) on day 21 was the highest in 25S. Growth parameters were higher in S with shorter irrigation intervals. Yellow symptom of leaf was occurred in 89.9% at 35S and 35L, where the temperature was high. Relative growth rate (RGR) and specific leaf weight (SLA) were high at 25/20℃ (25S, 25L), RGR tended to be high in the S treatment, and SLA in the L treatment. Water use efficiency (WUE) was high in the order of 25S, 25L > 15S > 15L, 35S, and 35L. As a result of the above, the growth and WUE were high at the temperature of 25/20℃.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.131-136
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• 1998

Attached algal community and several physico-chemicai characters were investigated at Seokjong hot spring in Chollabukdo in February and in April, 1997. The results of physico-chemicai factors are as follows : water temperatures were varied from 6.5$^{\circ}$C to 32.0$^{\circ}$C; pH range was 6.9 to 7.7; The levels of electric conductivity were 105 $\mu$mhos/cm to 477 $\mu$mhos/cm; chemical oxygen demand(COD) range was 1.5 mg/l to 21.2 mg/l; ammonia concentration was 0.20 mg/l to 8.74 mg/l; nitrate concentrations were 0.36 mg/l to 2.43 mg/l; phosphate concentration was N.D. to 0.52 mg/l; sulfur concentration was 14.6 mg/l to 66.1 mg/l. Attacched algal species were identified. Totally, 63 taxa were classified and composed of 4 phylum, 4 class, 10 order, 17 family and 31 genera. The total biomass of attacched algae was $1.036 \times 10^{7}$ cells/l that composed of $5.39 \times 10^{6}$ cells/l of blue-green algae, $4.05 \times 10^{6}$ cells/l of diatom and $0.93 \times 10^{6}$ cells/l of green algae. The succession of dominant species was Synechocystis thermalis. This could be due to the thermal wastewaters. in biotic indices tests, the values of dominance index(DI) were 0.33 to 0.67 in winter, 0.18 to 0.68 in spring. The values of diversity index(H') were 1.44 to 2.69 in winter, 1.62 to 2.89 in spring. And the values of eveness index (J) were 0.31 to 0.61 in winter, 0.37 to 0.65 in spring.

• BMB Reports
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• v.36 no.6
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• pp.586-592
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• 2003

Four putative promoters of the temperate mycobacteriophage L1 were cloned by detecting the $\beta$-galactosidase reporter expression in E. coli transformants that carried L1 specific operon-fusion library. All of the four L1 promoters were also found to express differentially in the homologous environment of mycobacteria. Of the four promoters, two were suggested to be the putative early promoters of L1 since they express within 0 to 10 min of the initiation of the lytic growth of L1. One of the putative early promoters showed a relatively better and almost identical activity in both E. coli and M. smegmatis. By a sequence analysis, we suggest that the L1 insert that contained the stronger early promoter possibly carries two convergent E. coli $\sigma^{70}$-like L1 promoters, which are separated from each other by about 300 nucleotides. One of them is the early promoter of L1 as it showed a 100% similarity with the early $P_{left}$ promoter of the homoimmune phage L5. The second promoter, designated P4, was suggested for its appreciable level of reporter activity in the absence of the -10 element of the $P_{left}$ equivalent of L1. By analyzing most of the best characterized mycobacteriophages-specific promoters, including the L1 promoter P4, we suggest that both the -10 and -35 hexamers of the mycobacteriophage promoters are highly conserved and almost similar to the consensus -10 and -35 hexamers of the E. coli $\sigma^{70}$ promoters.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.199-202
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• 1999

The experiment was conducted to find changes of growth response, free proline content and organic acids on manganese chloride toxicity($4,000mg\;l^{-1}$) for germination and early growth in rice. Root growth was increased in kinetin $10^{-3}M$ compared with control and germination rate was also increased in kinetin $10^{-3}M$ as 89%. Chlorophyll contents was slightly increased in kinetin $10^{-3}M$. Free proline content at 3days in Mn $4,000mg\;l^{-1}$ was higher than at 7 and 10 days, and all kinetin concentrations promoted free proline content. In organic acids, particularly, malic acid was remarkably increased in kinetin $10^{-3}M$ compared with control and Mn $4,000mg\;l^{-1}$.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.264-269
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• 2002

The production of exopolysaccharide from Zoogloea ramigera 115SLR in batch culture was affected by carbon sources, rifampicin concentration, inoculum size and cell density of starter culture. The increase of organic nitrogen concentration and cell density in defined medium by adding starter culture resulted in higher production of exopolysaccharide (EPS) within 2 days. Glucose and lactose as carbon sources showed EPS production of 10.7 gk and 10.5 ga, respectively. Higher EPS production was obtained with 2.5% (w/v) glucose. White sugar, brown sugar and galactose produced less than 10 gt of EPS. The optical density of starter culture affected on EPS yield, producing over 10 gt of EPS in the range of 1.0-1.7. In the presence of rifsmpicin, Z. ramigera 115SLR produced EPS of 12.9 gt. Molecular weight of EPS produced with/without rifampicin was determined with 1.367$\times$106 and 1.711$\times$106 g/mol using HPSEC-MALLS-RI, respectively.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.486-491
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• 2016

The aim of this research is to establish shoot regeneration system for 'Wonhwang' pear (Pyrus pyrifolia L.) using various concentrations of 1-Naphthaleneacetic acid (NAA) 0.01, 0.05, 0.1, 0.5 mg/L in combination with benzylaminopurine (BA) 3, 5, 10 mg/L. Medium containing 4.4 g/L of Murashige and Skoog (MS) medium with vitamins containing 8 g/L of plant agar and 30 g/L of sucrose with NAA 0.05 mg/L and BA 3 mg/L showed 13.3% of shoot regeneration rate. 'Wonhwang' showed no root growth on existing rooting media of P. pyrifolia cv. Niitaka, 'Whang-keumbae' and 'Bae Yun No. 3'. We evaluated the effect of concentration and kinds of plant growth regulators and carbon source to establish efficient rooting condition for 'Wonhwang' pear. In the result of using various concentrations of NAA 0.5 mg/L and 1.0 mg/L in combination with indolebutyric acid (IBA) 3, 5, 10 mg/L, rooting rate of 24% was observed using 1/4 Linsmaier and Skoog (LS) medium supplemented with 7.5 g/L glucose as carbon source and IBA 1.0 mg/L with NAA 1.0 mg/L.

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.137-142
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• 2008

Growth and survival rates dependent on the density of a pen sell, Atrina pectinata were measured from Duekryang bay in Korea. Annual water temperature and salinity of the study area were ranged from 14.5 to $28.0^{\circ}C$ and from 27.98 to 31.89 psu, respectively. The pH, DO, COD, DIN, Chl-a and SPM in the study area ranged from 7.78-8.35 mg/L, 7.07-7.90 mg/L, 1.20-1.70 mg/L, 2.88-6.02 mg/L, 0.20-0.79 mg/L and 10.8-21.4 mg/L. The IL, COD and AVS in sediments ranged from 4.0-4.6%, 7.28-10.76 mg/L and 0.03-0.05 mg/L respectively. The daily growth rate of shell height and total weight were 0.27%, 0.33%(5 indiv./$m^2$), 0.26, 0.29%(10 indiv./$m^2$) and 0.21, 0.20%(35 indiv./$m^2$). The survival rate also decreased along the density gradient; highest at the lowest density of 5 indiv./$m^2$ and lowest at the maximum density of 35 indiv./$m^2$.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.313-319
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• 2005

The effects of various carbon sources on the secretion of hGM-CSF, total protein and protease into the medium were investigated in transgenic tobacco cells. The dry cell weight (11.2 g/L) and wet cell weight (310.8 g/L) were highest at 30 g/L glucose after 5-day culture but, the dry cell weight (13.4 g/L) and wet cell weight (480 g/L) were highest at 30 g/L sucrose after 10-day culture. The total protein (110.3 mg/L), protease activity (3950 U/L) and total secreted hGM-CSF (56 mg/L) were highest at 30 g/L sucrose after 10-day culture. Stabilization of the total secreted protein and hGM-CSF in various carbon source concentrations was determined. Total secreted protein was most stabilized in the medium containing sucrose. However, the loss of the total protein was increased with the concentrations of high level in medium containing sorbitol, mannitol, fructose, and glucose. hGM-CSF was more stabilized in the medium containing sucrose than in the medium containing sorbitol, mannitol, fructose, glucose.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.176-182
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• 2009

Hydrogen producing bacterium, strain MeL 6-2 was isolated from the sludge of the factory areas in Anyang through the acclimation in basal salt medium (BSM) supplemented with 10 g/L of sucrose. Isolated strain MeL 6-2 was a facultative anaerobe which could grow in both aerobic and anaerobic environments. An aerobically grown pure culture isolated from enriched culture was analyzed by 16S rDNA sequencing and identified as Rhodopseudomonas sp. MeL 6-2. Effects of the concentrations of glucose and sucrose on the hydrogen production rate and the hydrogen production yield were investigated. When glucose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow without lag phase. An increased glucose concentration increased the specific hydrogen production rate linearly to $4.2\;mmol-H_2{\cdot}L^{-1}{\cdot}h^{-1}$ at 10 g/L, and $60\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$, but decreased slightly as the concentration increased to 12 g/L. The hydrogen production yield was maintained over a range from 2.6 to $3.1\;mol-H_2{\cdot}mol-glucose^{-1}$. When sucrose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow after ten hours. An increased sucrose concentration increased the specific hydrogen production rate and the hydrogen production yield to $163\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$ and to $4.5\;mol-H_2{\cdot}mol-sucrose^{-1}$, respectively.

• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.27-37
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• 1995

In anesthetized rats, we examined the possibility that endothelium-derived relaxing factor (EDRF) or nitric oxide (NO) released in response to cholinergic mechanism may contribute to the reflex autoregulation of cerebral blood flow. Suffusion with mock cerebrospinal fluid (CSF), containing acetylcholine (ACh, $10^{-9}{\sim}10^{-6}M$) evoked concentration-dependent vasodilatation of the resting pial artery (mean, $19.3{\pm}1.7{\mu}m$, n=36), which was significantly inhibited not only by $N{\omega}$-nitro-L-arginine (L-NNA, $10^{-5}M$) but also by methylene blue ($10^{-6}M$) and oxyhemoglobin ($10^{-6}M$). The muscarinic receptors in the endothelium of pial artery implicated in the release of EDRF were considered to be $M_1\;and\;M_3$ subtypes. When suffused with mock CSF containing L-arginine it caused a transient vasodilatation, which was strongly inhibited by LY 83583 ($10^{-5}M$), but not by L-NNA ($10^{-5}M$). Additionally, both ACh- and L-arginine-induced vasodilation were significantly inhibited by glibenclamide, a specific ATP-sensitive $K^+$ channel blocker. On the other hand, changes in pial arterial diameter were plotted as a function of changes in systemic arterial blood pressure. The slopes of regression lines for vasodilation and vasoconstriction were not affected by pretreatment with $10^{-5}M$ L-NNA, but significantly reduced by $3{\times}10^{-6}M$ glibenclamide. Thus it is suggested that the reflex vasodilation of rat pial arteries in response to a transient hypotension is not mediated by EDRF (NO).