• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.918-925
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• 2008

Controlling the light energy and major nutrients is important for high cell density culture of cyanobacterial cells. The growth phase of Anabaena variabilis can be divided into an exponential growth phase and a deceleration phase. In this study, the cell growth in the deceleration phase showed a linear growth pattern. Both the period of the exponential growth phase and the average cell growth rate in the deceleration phase increased by controlling the light intensity. To control the light intensity, the specific irradiation rate was maintained above $10\;{\mu}mol/s/g$ dry cell by increasing the incident light intensity stepwise. The final cell density increased by controlling the nutrient supply. For the control of the nutrient supply, nitrate, phosphate, and sulfate were intermittently added based on the growth yield, along with the combined control of light intensity and nutrient concentration. Under these control conditions, both final cell concentration and cell productivity increased, to 8.2 g/l and 1.9 g/l/day, respectively.

• Journal of Korea Foundry Society
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• v.26 no.1
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• pp.27-33
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• 2006

Phase evolutions involving nucleation stages together with diffusional growth have been examined in order to provide a guideline for determining rate limiting stages during phase evolutions. In multiphase materials systems in coatings, composites or multilayered structures, diffusion treatments often result in the development of metastable/intermediate phases at the reaction interfaces. The development of metastable phases during solid state interdiffusion demonstrates that the nucleation reaction can be one controlling factor. Also, the concentration gradient and the relative magnitudes of the component diffusivities provide a basis for a phase selection and the application of a kinetic bias strategy in the phase selection. For multicomponent alloy systems, the identification of the operative diffusion pathway is central to control phase formation. Experimental access to the nucleation and growth stage is discussed in thin film multi layers and bulk samples.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.4
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• pp.674-682
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• 2011

The present study was undertaken to investigate the effect of acupuncture & moxibustion therapy on the hair follicle growth of skin 5 days and 10 days by macroscopic, microscopic and immunohistochemical methods. The results were as follows : Macroscopic hair follicle growth of plum-blossom needle treated group and strong moxibustion treated group was more increase than that of control group. Microscopic hair follicle growth of plum-blossom needle treated group and strong moxibustion treated group was hair growing cycle, anagen phase VI and that of control group and weak moxibustion treated group was hair growing cycle, anagen phase IV. Immunohistochemical observations on the expression of various growth factors, enzyme and receptor in hair follicle cycle after local treatment of acupuncture & moxibustion therapy are as follows: Expression of fibroblast growth factor was more intense in epidermis in plum-blossom needle treated group, epidermis and secondary hair germ cells in strong moxibustion treated group than control group. Expression of epidermal growth factor was more intense in epidermis in all experimental groups, and secondary hair germ cells in moxibustion treated group than control group. Expression of c-kit receptor was more intense in epidermis, secondary hair germ cells, outer root sheath in all experimental groups than control group. Expression of protein kinase C-${\alpha}$ was more intense in epidermis, secondary hair germ cells, outer root sheath in all experimental groups than control group. Expression of vascular endothelial growth factor was more intense in epidermis, bulge, secondary hair germ cells, outer root sheath in plum-blossom needle treated group and strong moxibustion treated group than control group. We concluded that acupuncture & moxibustion therapy related to the expression of various growth factors, enzymes and receptor on the hair growth cycle for hair growth.

• BMB Reports
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• v.29 no.3
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• pp.221-224
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• 1996

To examine the growth-phase dependent control of Escherichia coli rnpB gene we used a combination of Northern analysis for RNA determination and Southern analysis for plasmid DNA determination. The relative amounts of metabolically unstable transcript derived from the internally deleted rnpB gene harbored on a multicopy plasmid as well as the relative plasmid contents were measured by Northern analysis and Southern analysis, respectively, of total nucleic acids from E coli cells containing the plasmid. The relative transcription activity of the rnB was represented by a ratio of the relative amount of the transcript to that of the plasmid DNA during bacterial growth. The rnpB transcription increased rapidly with time during exponential growth, but started to decrease before the transition period of an exponential growing cell culture into the stationary phase. Although the expression pattern was similar to the changes of ${\beta}-galactosidase$ activity expressed from the lysogenic strain carrying the chromosomal rnpB-lacZ fusion which were shown in a previous work, the present data appears to represent a more actual growth-phase control of the rnpB transcription than the previous data by the ${\beta}-galactosidase$ assay. In addition the present method described for a direct analysis of both RNA and plasmid DNA provides a rapid and efficient method that can applied to an examination of transcription control by using a multicopy plasmid.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.351-359
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• 2006

In this article, we present a new slow-start variant, which improves the throughput of transmission control protocol (TCP) Vegas. We call this new mechanism Gallop-Vegas because it quickly ramps up to the available bandwidth and reduces the burstiness during the slow-start phase. TCP is known to send bursts of packets during its slow-start phase due to the fast window increase and the ACK-clock based transmission. This phenomenon causes TCP Vegas to change from slow-start phase to congestion-avoidance phase too early in the large bandwidth-delay product (BDP) links. Therefore, in Gallop-Vegas, we increase the congestion window size with a rate between exponential growth and linear growth during slow-start phase. Our analysis, simulation results, and measurements on the Internet show that Gallop-Vegas significantly improves the performance of a connection, especially during the slow-start phase. Furthermore, it is implementation feasible because only sending part needs to be modified.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.394-400
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• 1990

Maximization of productivity of recombinant cell fermentations requires consideration of the inverse relationship between the host cell growth rate and product formation rate. The problem of maximizing a weighted performance index was solved by using optimal control theory for recombinant E. coli fermentation. Concentration of a growth inhibitor was used as a control variable to manipulate the specific growth rate, and consequently the cloned-gene expression rate. Using a simple unstructured model to describe the main characteristics of this system, theoretical analysis showed that the optimal control profile results in an initial high growth rate phase followed by a low growth rate and high product formation rate phase. Numerical calculations were done to determine optimal switching times from the growth to the production stage for two representative cases corresponding to different dependency of the product formation rate on the growth rate. For the case when product formation rate is sensitive to the specific growth rate, the optimized operation yields about 60% increase in the final product concentration compared with a simple batch fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.231-236
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• 2001

This study was conducted to investigate the effect of supplemented enzyme complex on growth performance and nutrient digestibility in pigs weaned at 14 days of age. Eighty pigs ($4.02{\pm}0.11kg$ of average body weight) were allotted in a completely randomized block design. Treatments were as follows: 1) control (negative), 2) control (positive, $Kemzyme^{(R)}$), 3) 0.1%, 4) 0.2% and 5) 0.3% of newly developed enzyme complex. Each treatment has 4 replicates with 4 pigs per replicate. During phase I period (d 0 to 14), ADG and ADFI were numerically higher in pigs fed diets supplemented enzyme complex regardless of their inclusion levels compared to pigs fed control (negative) diet. Feed/gain (F/G) was also better in pigs fed enzyme complex diet than that of pigs fed control (negative) diet. In addition, with increasing the inclusion level of enzyme complex, ADG and ADFI were improved. However, there was no significant difference between treatment in all growth parameters. During phase II period (d 15 to 28), ADG, ADFI and F/G showed the same tendency as in phase I period. For overall period (d 0 to 28) ADG was highest in pigs fed diet included 0.2% enzyme complex in all treatments but not significantly different. During phase I period, the digestibilities of all nutrients did not showed any significant difference between treatments. However, pigs fed diet contained enzyme complex and positive control diet (Kemzyme) showed numerically higher nutrient digestibilities in all nutrients than pigs fed negative control diet. During phase II period, data were consistent with those observed in phase I period. Especially, the digestibility of phosphorus was significantly higher in pigs fed diets contained enzyme complex including phytase than pigs fed control (negative and positive) diets (p<0.05). For overall experimental period, fecal or ileal amino acid digestibility were not affected by dietary treatment. Enzyme complex newly developed and used in this study can be possibly recommended as a growth promoter when supplemented in diet for early weaned piglets.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.791-799
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• 2011

This study examined the effect of restricting feed intake and the subsequent compensatory growth in Guzera females. Eighteen animals with an initial age of 21 months and a mean weight of 268.17 kg were placed in three groups according to the alimentary regime: feed ad libitum; feed restricted to 20% dry matter; and feed restricted to 40% dry matter. In the restricted feed phase, the dry mater intake decreased as the restriction levels increased, influencing the reduction in intake of other nutrients. In the realimentation phase, the 40% restricted feed group ingested more dry matter (% BW) and crude protein ($weight^{0.75}$) than the group fed ad libitum (p<0.001). The serum nutrient concentrations were inversely proportional (p<0.001) to the restriction level, and there was no difference (p>0.001) in the realimentation phase. In the restricted feed phase, the final live weight decreased (p<0.05) as the restriction level increased. For the daily mean weight gain in the control group, there was no difference (p>0.05) compared to the animals with 20% feed restriction, but this was higher than in the group with 40% feed restriction. In the re-alimentation phase, the group with 40% feed restriction achieved higher weight gain rates, which was different from the control and 20% restriction groups. In both phases, the animals in the group with 40% feed restriction presented better feed conversion which was different (p<0.05) from the control group. In the feed restriction phase, it was observed that the intake of N, nitrogen excreted in feces and urine, nitrogen balance and nitrogen retention decreased (p<0.05) with the restriction level. None of the variables were influenced in the re-alimentation phase. These results show that feed restriction by 40% can be adopted as a nutritional management practice.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.907-915
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• 2010

Three hundred and seventy-three steers (approximately 7 mo of age and $247{\pm}19.4\;kg$) were utilized to determine the effects of trace mineral (TM) source and growth implants on trace mineral status. Steers were blocked by ranch, post-weaning treatment within ranch, stratified by initial body weight, and randomly assigned to one of 36 pens (9-12 head/pen). Treatment consisted of: I) control (no supplemental Cu, Zn, Mn, and Co), ii) inorganic trace minerals, and iii) organic trace minerals. Six pens of steers per treatment received a growth implant at the beginning of the experiment and were re-implanted during the finishing phase. The remaining steers received no growth implants. Steers were fed a corn silage-based growing diet for 56 d then were gradually switched to a high concentrate finishing diet. Treatments during the finishing phase consisted of: i) control (no supplemental Zn); ii) inorganic Zn (30 mg of Zn/kg DM from $ZnSO_4$); and iii) organic Zn (iso-amounts of organic Zn). By the end of the growing and finishing phases, implanted steers had greater (p<0.01) plasma Cu concentrations than non-implanted steers. During the growing phase, liver Cu concentrations (p<0.01) and plasma Zn concentrations (p<0.02) were greater in steers supplemented with TM compared to control steers. Steers supplemented with inorganic minerals had greater liver Cu concentrations than steers supplemented with organic minerals at the beginning (p<0.01) and end (p = 0.02) of the growing phase. During both the growing (p = 0.02) and finishing phases (p = 0.05), nonimplanted control steers had greater plasma Cu concentrations than non-implanted steers supplemented with TM, whereas, implanted control steers had similar plasma Cu concentrations than implanted steers supplemented with TM. Non-implanted steers that received inorganic TM had lower plasma Cu concentrations (p = 0.03) during the growing phase and ceruloplasmin activity (p<0.04) during the finishing phase than non-implanted steers that received organic TM, whereas, implanted steers supplemented with either organic or inorganic TM had similar plasma Cu concentrations.

• Biomolecules & Therapeutics
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• v.23 no.2
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• pp.174-179
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• 2015

BP201, porcine lung tissue-derived phospholipids, consists of phosphatidylcholine as a major phospholipid species. BP201 promoted hair growth after application onto the shaved backs of BALB/c and C3H mice. Its effect was enhanced when applied together with minoxidil (MNX) in C3H mice. When the tissue specimens prepared from the shaved skins of BP201-treated and control mice were microscopically examined, the total numbers of hair follicles in both anagen and telogen phases of BP201-treated mice were significantly higher than those of control mice. The numbers of hair follicles in the anagen phase of BP201-treated mice were also higher than those of control mice. In combination with MNX, BP201 further increased the total number of hair follicles, but did not alter the percentage of hair follicles in the anagenic phase. BP201 also increased the proliferation of human hair follicle dermal papilla cells. Collectively, BP201 possesses hair growth promoting potential, which would suggest its use singly or in combination for hair growth products.