• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.144-154
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• 2008

The purpose of this study was to describe quantitatively trophic structures and to analyze energy flows in the Lake Namyang using the Ecopath with ecosim (Walter et al., 1997). The sampling and analyses were carried out at 6 sampling sites of the Lake Namyang during May and November in 2007. A total of 10 groups were considered in this study (detritus, macrophytes, phytoplankton, zooplankton, zoobenthos, Cyprinus carpio, Carassius cuvieri, Carassius auratus, Pseudobagrus fulvidraco and other fishes) to assess the trophic relationship, energy flows and interactions between them. As a result, it was concluded that Lake Namyang was consisted of primary producers (Detritus, Macrophytes, Phytoplankton), primary consumers (Zooplankton, Zoobenthos, Cyprinus carpio, Carassius cuvieri, Carassius auratus, Other fishes) and secondary consumer (Pseudobagrus fulvidraco). The total system throughput was estimated at $14.1\;kg\;m^{-1}\;year^{-1}$ including a consumption of 39%, exports of 21%, respiratory flows of 12% and flows into detritus of 28%. MTI analyses indicate that Pseudobagrus fulvidraco have positive impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. On the other hand, other fishes have negative impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. All the functional groups except detritus had a negative impact on themselves and this may show within-group competition for the same resources.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.4
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• pp.348-354
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• 2011

Composite resin has been widely used for eroded enamel. But, as there have been many reports about the differences in physicochemical characteristics of eroded enamel compared with sound enamel, an additional effort was thought necessary to obtain the optimal bond strength. As a possible answer, we came to think about the application of infiltrant resin which is known to have an excellent penetration capacity into enamel. This study was performed for the purpose of comparing the bond strength of composite restoration with or without infiltrant resin under adhesives on the artificially eroded enamel. 60 extracted sound maxillary primary incisors were selected and divided into group 1, 2, 3 according to the number of artificial erosion cycling for 5 minute duration in 1% citric acid of pH 3.2 at $37^{\circ}C$. And the labial surfaces were divided into 3 areas; group A, only resin adhesive was used, group I, only infiltrant resin, group IA, infiltrant resin followed by resin adhesive. Afterwards, every specimen was restored with composite resin. Microtensile bond strength was measured and failure modes were observed. The obtained results were as follows: 1. In comparing the bond strength by the degree of enamel erosion, it was revealed the highest bond strength in group 1, followed by group 2 and 3, showing the lowest bond strength in most eroded group(p<0.05). 2. In comparing the bond strength by surface treatment methods, group IA and I showed higher value than group A(p<0.05), with unsignificant difference between group I and IA(p>0.05). 3. In observation of failure mode, it was shown higher frequency of cohesive failure in order of 1-2-3 and IA-I-A. Conclusively, it was shown decreasing tendency of bond strength as the enamel is more eroded, and infiltrant resin was thought helpful to replace or add to the resin adhesive for optimal bonding with eroded enamel.

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.1
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• pp.31-38
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• 2008

Ad-Hoc network is a network architecture which has no backbone network and is deployed temporarily and rapidly in emergency or war without fixed mobile infrastructures. All communications between network entities are carried in ad-hoc networks over the wireless medium. Due to the radio communications being extremely vulnerable to propagation impairments, connectivity between network nodes is not guaranteed. Therefore, many new algorithms have been studied recently. This study proposes the secondary header approach to the cluster based routing protocol (CBRP). The primary header becomes abnormal status so that the primary header can not participate in the communications between network entities, the secondary header immediately replaces the primary header without selecting process of the new primary header. This improves the routing interruption problem that occurs when a header is moving out from a cluster or in the abnormal status. The performances of proposed algorithm ACBRP(Advanced Cluster Based Routing Protocol) are compared with CBRP. The cost of the primary header reelection of ACBRP is simulated. And results are presented in order to show the effectiveness of the algorithm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.255-264
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• 2003

A study was conducted to determine the effects of pig slurry application on forage yield and growth of fazing Hanwoo heifer in a mixed pasture. To each of three treatments 1.4ha were alloted a control applied with only chemical fertilizer (N-P-K=150-150-120kg/ha), two pig slurry lots applied with the amount to allow 100% (150 kg/ha) or 150% (225 kg/ha) of N used in the control. A randomized block design was used without replication. Cattle were allowed to graze continuously during the experimental period. Results obtained were as follows: Total dry matter yield was 16,291, 15,632 and 16,320 kg/ha for chemical fertilizer. pig slurry 100% and 150％, respectively. The pasture was dominated by perenial ryegrass during the first gazing season, but by orchard grass and perenial ryegrass (60∼70%) and red clover (20∼30%) during the second grazing season. Average gazing rate per ha was 2.75∼2.76 animal units and daily weight gain of grazing cattle was not different among treatments ranging from 0.563 to 0.580 kg. Total weight gain of grazing cattle per ha during the grazing period was 541, 541 abd 555 kg for chemical fertilizer, pig -slurry 100 and 150%, respectively. RBC, WBC, total protein and albumin etc. concentrations in blood were normal in all treatments.

• Journal of Korean Society of Forest Science
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• v.21 no.1
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• pp.1-34
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• 1974

The author intended to investigate external and internal changes in the cone structure, changes in water content, sugar, fat and protein during the period of seed maturation which bears a proper germinability. The experimental results can be summarized as in the following. 1. Male flowers 1) Pollen-mother cells occur as a mass from late in April to early in May, and form pollen tetrads through meiosis early and middle of May. Pollen with simple nucleus reach maturity late in May. 2) Stamen number of a male flower is almost same as the scale number of cone and is 69-102 stamens. One stamen includes 5800-7300 pollen. 3) The shape is round and elliptical, both of a pollen has air-sac with $80-91{\mu}$ in length, and has cuticlar exine and cellulose intine. 4) Pollen germinate in 68 hours at $25^{\circ}C$ with distilled water of pH 6.0, 2% sugar and 0.8% agar. 2. Female flowers 1) Ovuliferous scales grow rapidly in late April, and differentiation of ovules begins early in May. Embryo-sac-mother cells produce pollen tetrads through meiosis in the middle of May, and flower in late May. 2) The pollinated female flowers show repeated divisions of embryo-sac nucleus, and a great number of free nuclei form a mass for overwintering. Morphogenesis of isolation in the mass structure takes place from the middle of March, and that forms albuminous bodies of aivealus in early May. 3. Formation of pollinators and embryos. 1) Archegonia produce archegonial initial cells in the middle and late April, and pollinators are produced in the late April and late in early May. 2) After pollination, Oespore nuclei are seen to divide in the late May forming a layer of suspensor from the diaphragm in early June and in the middle of June. Thus this happens to show 4 pro-embryos. The organ of embryos begins to differentiate 1 pro-embryo and reachs perfect maturation in late August. 4. The growth of cones 1) In the year of flowering, strobiles grow during the period from the middle of June to the middle of July, and do not grow after the middle of August. Strobiles grow 1.6 times more in length 3.3 times short in diameter and about 22 times more weight than those of female flower in the year of flowering. 2) The cones at the adult stage grow 7 times longer in diameter, 12-15 times shorter diameter than those of strobiles after flowering. 3) Cone has 96-133 scales with the ratio of scale to be 69-80% and the length of cone is 11-13cm. Diameter is 5-8cm with 160-190g weight, and the seed number of it is 90-150 having empty seed ratio of 8-15%. 5. Formation of seed-coats 1) The layers of outer seed-coat become most for the width of $703{\mu}$ in the middle of July. At the adult stage of seed, it becomes $550-580{\mu}$ in size by decreasing moisture content. Then a horny and the cortical tissue of outer coats become differentiated. 2) The outer seed-coat of mature seeds forms epidermal cells of 3-4 layers and the stone cells of 16-21 layers. The interior part of it becomes parenchyma layer of 1 or 2 rows. 3) Inner seed-coat is formed 2 months earlier than the outer seed-coat in the middle of May, having the most width of inner seed-coat $667{\mu}$. At the adult stage it loses to $80-90{\mu}$. 6. Change in moisture content After pollination moisture content becomes gradually increased at the top in the early June and becomes markedly decreased in the middle of August. At the adult stage it shows 43~48% in cone, 23~25% in the outer seed-coat, 32~37% in the inner seed-coat, 23~26% in the inner seed-coat and endosperm and embryo, 21~24% in the embryo and endosperm, 36~40% in the embryos. 7. The content compositions of seed 1) Fat contents become gradually increased after the early May, at the adult stage it occupies 65~85% more fat than walnut and palm. Embryo includes 78.8% fat, and 57.0% fat in endosperm. 2) Sugar content after pollination becomes greatly increased as in the case of reducing sugar, while non-reducing sugar becomes increased in the early June. 3) Crude protein content becomes gradually increased after the early May, and at the adult stage it becomes 48.8%. Endosperm is made up with more protein than embryo. 8. The test of germination The collected optimum period of Pinus koraiensis seeds at an adequate maturity was collected in the early September, and used for the germination test of reduction-method and embryo culture. Seeds were taken at the interval of 7 days from the middle of July to the middle of September for the germination test at germination apparatus.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.392-399
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• 2013

This study aimed to investigate responses of photosynthesis, plant growth, and phytochemical contents to different artificial light sources for 'Seneca RZ' and 'Gaugin RZ' two butterhead lettuce (Lactuca sativa L.). In this study, fluorescent lamps (FL), three colors LEDs (red, blue and white, 5 : 4 : 1; RBW) and metalhalide lamps (MH) were used as artificial lighting sources. Photoperiod, air temperature, relative humidity, EC, and pH in a cultivation system were maintained at 16/8 h, $25/15^{\circ}C$, 60~70%, $1.4{\pm}0.2dS{\cdot}m^{-1}$, and $6.0{\pm}0.5$, respectively. The photosynthetic rate of both two butterhead lettuce were the highest under RBW in middle growth stage. However, in late growth stage, the photosynthetic rate of both two butterhead lettuce were higher under RBW and MH than FL. The light sources showed significant results for plant growth but those effects were different to variety. Fresh and dry weight of 'Gaugin RZ' butterhead lettuce under MH were heavier than other lights in all growth stages. Growth of 'Seneca RZ' butterhead lettuce was maximized highest under MH in middle growth stage and FL in late growth stage. In the leaf tissue of 'Seneca RZ' butterhead lettuce, tipburn symptom occurred under all light sources and in the leaf tissue of 'Gaugin RZ' butterhead lettuce, it occurred under two light sources except for fluorescent lamps in late growth stage. kinds of lamp affect plant growth more than plant quality. Relative growth rate of both two butterhead lettuce was faster in middle growth stage than late stage. Growth of 'Gaugin RZ' was shown by kinds of lamp in middle growth stage and but it was not significantly affected by light sources and variety in late stage. Most of the phytochemical contents of two butterhead lettuce were significantly affected by different light sources. Contents of all vitamins showed higher than other light sources on RBW for both two lettuce, especially ${\beta}$-Carotene content of 'Gaugin RZ' was the highest. Plant growth, photosynthesis, and phytochemical contents were observed significant effects by different light sources for two butterhead lettuce but those effects were highly different between variety and kinds of phytochemicals. Therefore, the selection of optimum light source should be considered by variety and kinds of phytochemicals in the plant factory.

• Reproductive and Developmental Biology
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• v.29 no.1
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• pp.1-7
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• 2005

Telomeres consisting of (TTAGGG)n tandem repeat DNA sequences and associated proteins are essential for chromosome stability and related with cell senescence, apoptosis and cancer. The telomerase is a ribonucleoprotein which act as a template for the synthesis of telomeric DNA. This study was carried out to identify the distribution of telomeres on mouse chromosomes and also to analyze the amount of telomeres and telomerase activity of mouse embryos at early embryonic stages. Germ cells and early embryos from 1 cell to blastocyst stage were analyzed. The amount of telomeres was analyzed by quantitative fluorescence in situ hybridization technique(Q-FISH) using a human telomeric DNA probe, and telomerase activity was measured by telomeric repeat amplification protocol assay(TRAP). In results, the telomeres on mouse chromosomes were distributed at the ends of all autosomes and sex chromosomes. Although the quantity of telomeres varied among chromosomes, most of chromosomes had higher amount in q-arm telomeres than in p-arm telomeres. The results of Q-FISH indicated that the relative amount of telomeres of mouse embryos in each embryonic stage was approximately the same except the higher amount in blastocysts. Using TRAP assay on mouse embryos, telomerase activity was detected in all preimplantation stages from mature oocytes to blastocysts. Especially the telomerase activity was significantly increased at the morula and blastocyst stage. In conclusion, there may be a close association between the amount of telomeres and telomerase activity in early embryonic stages, and analysis of telomere quantity and telomerase activity on early development will be helpful for the investigation of embryogenesis and embryonic cell differentiation in mice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.172-180
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• 2009

This study was carried out to compare the physicochemical characteristics and sensory quality of Sogokju (Korean traditional rice wine) prepared with waxy rice varieties. Among tested waxy rice varieties, highest protein contents (8.11%) was observed in cv. Sangjuchal, and highest whiteness and L-value were observed in cv. Hwaseonchal, while no significant differences in gelatinization temperature could be observed among tested varieties, and cv. Boseokchal and Sinseonchal exhibited higher breakdown viscosity compared to the others. The alcohol contents of Sogokju with waxy rice varieties ranges from 13.0 to 13.4%, and the brix degree and turbidity were within the range of 20.5 to 24.6 $^{\circ}Bx$, and 0.0344 to 0.0530, respectively. The highest L-value (6.90), b-value (l.45), pH (4.79), total acidity (0.8384%), and glucose content (10.843 g/100 ml) could be observed in Sogokju made with cv. Sangjuchal. The organic acids such as succinic acid, malic acid, citric acid and oxalic acid could be detected in Sogokju. Although no variety-dependant differences in appearance, aroma, and taste could be found in sensory evaluation, Sogokju made with cvs. Sinseonchal, Haepyeongchal, and Hwaseonchal showed higher overall quality than Sogokju made with cv. Dongjinchal, which is most widely used for Sogokju used for Sogokju production nowadays.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.457-465
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• 2009

The characteristics of Holstein colostrum according to the methods that were employed in processing it were analyzed in this study to improve its industrial utilization. Colostrum samples were collected from the dairy farm of the National Institute of Animal Science (NIAS). The milk fat, protein, lactose, and SNF contents of colostrum were 4.34, 6.99, 3.37, and 11.10%, respectively. The effects of spray drying, freeze drying, freezing, acidification, and inoculation of lactic-acid bacteria on the characteristics of colostrum were then compared. The freezing of colostrum was found to be proper for long-term storage in a farm. Freeze-dried colostrum powder could not meet the processing requirements and the component standards for animal products in terms of the total bacterial and coliform bacteria counts, but spray-dried colostrum powder could meet the microbiological requirements because of its bactericidal effect during the spray-dry treatment. The inoculation of lactic-acid bacteria showed a better inhibitory effect on coliform than the acidification treatment, but protein precipitation appeared because of the low pH and the high acidity. To estimate the effects of the processing methods employed on the IgG of colostrum, the IgG contents of the milk treated by long temperature long time (LTLT) ($65^{\circ}C$, 30 min), by inoculating the lactic acid bacteria starter, by spray drying, and by freeze drying were measured. The IgG contents of the colostrum were changed significantly by the processing treatment employed, from 53.98 mg/mLto 33.28, 34.82, 21.98, and 36.89 mg/mL, respectively.

• Korean Journal of Biological Psychiatry
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• v.12 no.1
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• pp.42-61
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• 2005

Objectives:The ginsenoside Rg1 and Rb1, the major components of ginseng saponin, have neurotrophic and neuroprotective effects including promotion of neuronal survival and proliferation, facilitation of learning and memory, and protection from ischemic injury and apoptosis. In this study, to investigate the molecular basis of the effects of ginsenoside on neuron, we analyzed gene expression profiling of SH-SY5Y human neuroblastoma cells treated with ginsenoside Rg1 or Rb1. Methods:SH-SY5Y cells were cultured and treated in triplicate with ginsenoside Rg1 or Rb1($80{\mu}M$, $40{\mu}M$, $20{\mu}M$). The proliferation rates of SH-SY5Y cells were determined by MTT assay and microscopic examination. We used a high density cDNA microarray chip that contained 8K human genes to analyze the gene expression profiles in SH-SY5Y cells. We analyzed using the Significance Analysis of Microarray(SAM) method for identifying genes on a microarray with statistically significant changes in expression. Results:Treatment of SH-SY5Y cells with $80{\mu}M$ ginsenoside Rg1 or Rb1 for 36h showed maximal proliferation compared with other concentrations or control. The results of the microarray experiment yielded 96 genes were upregulated(${\geq}$3 fold) in Rg1 treated cells and 40 genes were up-regulated(${\geq}$2 fold) in Rb1 treated cells. Treatment with ginsenoside Rg1 for 36h induced the expression of some genes associated with protein biosynthesis, regulation of transcription or translation, cell proliferation and growth, neurogenesis and differentiation, regulation of cell cycle, energy transport and others. Genes associated with neurogenesis and neuronal differentiation such as SCG10 and MLP increased in ginsenoside Rg1 treated cells, but such changes did not occur in Rb1-group. Conclusion:Our data provide novel insights into the gene mechanisms involved in possible role for ginsenoside Rg1 or Rb1 in mediating neuronal proliferation or cell viability, which can elicit distinct patterns of gene expression in neuronal cell line. Ginsenoside Rg1 have more broad and strong effects than ginsenoside Rb1 in gene expression and related cellular physiology. In addition, we suggest that SCG10 gene, which is known to be expressed in neuronal differentiation during development and neuronal regeneration during adulthood, may have a role in enhancement of activity dependent synaptic plasticity or cytoskeletal regulation following treatment of ginsenoside Rg1. Further, ginsenoside Rg1 may have a possible role in regeneration of injured neuron, promotion of memory, and prevention from aging or neuronal degeneration.