• Journal of Korea Technology Innovation Society
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• v.12 no.3
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• pp.525-544
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• 2009

There's a way to recover unbalanced industrial structure between large size company (LEs) and small size company(SMEs). It's called middle size company (MEs) which can be the magic bullet for Korea to be more healthier than ever. but there are problems with MEs in Korea. Not only the number of MEs is too low compared to developed country's but also the status of amount of research developmental revenue, R&D concentration isn't that satisfied. That's why we need to focus on MEs which was out of center stage until now. Before discussing about how to foster MEs, we need to know what cause MEs makes weak. This research contains actual condition of R&D investment in MEs based on data from Korea information service. Also, survey data can help to know exact factor which make hard to invest research development. Expecially, this research give the answers that relation between the course of growth and concentration of R&D which was observed that has reciprocal relationship.

• Journal of the Korean Home Economics Association
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• v.19 no.3
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• pp.21-32
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• 1981

Clothing must have the individual beauty and the function that one can do one's body movement freely. therefore, from the human engineering view point, the exact measurement of the human body and the analysis of it's results must be applied to clothing because the arm works most. In this study, the skin surface of arm was investigated by shell made of Alginate of each movement. And by sometic method the rate of expansion and contraction of each section, inter-relation among the bust girth, axillary arm girth and scye girth and between the shoulder length right and the under axilla waist length were calculate4d. With these results, cap height, breadth of a sleeve and arm hole girth of existing sleeve pattern have been compared and analysed. The results are as follows; 1) According to the developmental figures of shell, the whole area change was small but that of shape was remarkable in M 4, 9, 13. The change of the Block 1 was particular. 2) Over arm length was contracted in all movements except M6 and under arm length expanded. The changes of sections a, b, c are large, while those of sections d, e are small. 3) In terms of latitudes, change of fore-arm region was small. The rate of scye girth varied from 14.3% of M13 to-5.6% of M2. The breadth of a sleeve expanded in all movements, and especially the front region expanded more than the back. 4) The relation between the shoulder length right and under axilla waist length, in all occasions, was contracted mutually, and one contracted, the other expanded. Therefore, in clothing construction when we consider the function of the arm it is better to widen the arm hole and the breadth of a sleeve at the same time than no widen the shoulder length by lowering the upper part of the upper side seam line.

• Animal cells and systems
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• v.6 no.1
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• pp.69-74
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• 2002

Recent evidence has suggested that trunk neural crest cell generally assumed to have equivalent differentiation potentials, demonstrate differentiation bias along the anterior/posterior axis. In amphibian and fish, neural crest cells give rise to three chromatophore types, melanophores, xantho-phores, and iridophores. Each pigment cell type has distinct characteristics but there is speculation about the cellular plasticity that exists among them. Neural crest cells migrate along specific routes, ventromedially and dorsolaterally. Neural crest cells that travel dorsolaterally are the first cells to begin migration in the axolotl and are the major contributors to the visible pigment pattern. Many factors and mechanisms that are responsible for guiding migratory neural crest cells along potential pathways or determining their fate remain unknown. A single lineage of the crest, which becomes restricted to one of the three pigment cell types, gives us the opportunity to examine the existence of neural crest stem cell populations and cellular plasticity. Study presented here showed results from recent in vitro studies designed to identify parameters influencing differentiation events of individual neural crest-derived pigment cell lineages. Melanophore production from neural crest explants originating from different levels along the anterior/posterior axis of wild type-axolotl embryos were compared and demonstrate that the differentiation of melanophores is enhanced in subpopulation of neural crest treated with forskolin. Forskolin (an adenylate cyclase activator) increases intracellular CAMP concentration and eventually activates the protein kinase-A signaling pathway. Melanophore number, melanin content, and tyrosinase activity in explants taken from the anterior-most region of the crest increased significantly in response to forskolin treatment. This study suggests implications of region specific influences and developmental regulation in the development of pigment pattern.

• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.323-327
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• 1995

This experiment was carried out to observe the origin and developmental pattern of somatic embryos of Oenanthe javanica ($B^{L}.$) DC. The experiment included observation of embryogenic cells and their development stages by light microscope, transmission electron microscope and scanning electron microscope. The embryogenic cells, which were smaller than non-embryogenic cells in size with expanded nucleus and dense cytoplasm. When stained with hematoxylin, the embryogenic cells were readily distinguished from the non-embryogenic cells of which cell walls were stained with safranin. It was observed at somatic embryos developed from single cells on the epidermis of developing embryos or in the surface or inside of embryogenic clumps by segmentation pattern. Observation with a transmission electron microscope revealed that the embryogenic cells had dense cytoplasm expanded nucleus, small vacuoles, large amyloplasts containing starch grains, and abundant organelles including lipid bodies. Under a scanning electron microscope, embryogenic callus was shown to consist of very smaller cells than non-embryogenic cells in an orderly arrangement and covered with a net-like structure, while the non-embryogenic callus consisted of large cells, irregular in size and arrangement, and covered with a gelatin-like material.

• Biomedical Science Letters
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• v.13 no.3
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• pp.239-244
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• 2007

Hoxc8 is one of the homeotic developmental control genes regulating the expression of many downstream target genes, through which animal body pattern is established during embryonic development. In previous proteomics analysis, proliferating cell nuclear antigen (PCNA) which is also known as cyclin, has been implied to be regulated by Hoxc8 in F9 murine embryonic teratocarcinoma cell. When the 5' upstream region of PCNA was analyzed, it turned out to contain 20 Hox core binding sites (ATTA) in about 1.17 kbp (kilo base pairs) region ($-520{\sim}-1690$). In order to test whether this region is responsible for Hoxc8 regulation, the upstream 2.3 kbp fragment of PCNA was amplified through PCR and then cloned into the pGL3 basic vector containing a luciferase gene as a reporter. When the luciferase activity was measured in the presence of effector plasmid (pcDNA : c8) expressing murine Hoxc8, the PCNA promoter driven reporter activity was reduced. To confirm whether this reduction is due to the Hoxc8 protein, the siRNA against Hoxc8 (5'-GUA UCA GAC CUU GGA ACU A-3' and 5'-UAG UUC CAA GGU CUG AUA C-3') was prepared. Interestingly enough, siRNA treatment up regulated the luciferase activity which was down regulated by Hoxc8, indicating that Hoxc8 indeed regulates the expression of PCNA, in particular, down regulation in NIN3T3 cells. These results altogether indicate that Hoxc8 might orchestrate the pattern formation by regulating PCNA which is one of the important proteins involved in several processes such as DNA replication and methylation, chromatin remodeling, cell cycle regulation, differentiation, as well as programmed cell death.

• Journal of Life Science
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• v.9 no.1
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• pp.29-34
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• 1999

Cotyledon and hypocotyl explants of perilla were cultured on MS medium containing a combined concentration of BA(0.5, 1.0 and 1.5mg/$\ell$) and NAA(0.1, 0.5 and 2.0mg/$\ell$) in order to regenerate the explant and induce the callus. The best regeneration of the explant and induction of the callus were observed in a combined concenteration of 0.5mg/$\ell$ of BA and 0.5mg/$\ell$ NAA both in cotyledon and hypocotyl explants. In cotyledon explants, rooting was achieved upon transferring shoots to MS medium containing 0.5mg/$\ell$ of BA and 0.1mg/$\ell$ of NAA. We also investigated the change of protein and RNA content on developmental stage of callus and plant regeneration of perilla. Protein content was increased but RNA content was decreased as the culture period increases. The banding pattern of polypeptide revealed that both 30KD and 45KD polypeptides were obvious in cotyledon obtained from pre-culture explants, but only 30KD polypeptide was further getting obvious as the culture period increases.

• Reproductive and Developmental Biology
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• v.28 no.4
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• pp.261-265
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• 2004

The present study was conducted to assess sperm characteristics in miniature-pig. The semen samples were transported to the laboratory at 17℃ within 3 hours after collection. The extended semen was stored at 17℃, and sperm quality was evaluated at 0, 1, 3, 5 and 7 days after storage. The semen volume of miniature-pig (62±22㎖) was significantly (p<0.05) lower than that of Duroc (155±25㎖) and Yorkshire (154±23㎖). Significant differences were also observed in sperm concentrations. During 3 days of storage, sperm viability did not differ among miniature-pig, Duroc and Yorkshire. However, the viability was significantly (p<0.05) lower in miniature-pig than in Duroc and Yorkshire semen after Day 3 of storage. In abnormality, acrosome intactness and intensity, there were no differences among miniature-pig, Duroc and Yorkshire semen. On the other hand, the viability of frozen-thawed sperm in miniature-pig was significantly (p<0.05) lower than in that of Duroc and Yorkshire. This study also examined CTC patterns in frozen-thawed spermatozoa. The rates of AR pattern were higher in miniature-pig than in Duroc and Yorkshire. However, no difference was found in F, B and AR patterns. The results of present study suggest that further research is necessary to develop of semen extender and freezing methods to improve sperm quality in miniature-pig.

• Development and Reproduction
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• v.16 no.1
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• pp.53-58
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• 2012

Circadian rhythmicity (e.g. secretory pattern of hormones) plays an important role in the control of reproductive function. We hypothesized that the alteration of feeding pattern via meal time shift/restriction might disrupt circadian rhythms in energy balance, and induce changes in reproductive activities. To test this hypothesis, we employed simple animal model that not allowing $ad$ $libitum$ feeding but daytime only feeding. The animals of $ad$ $libitum$ feeding group (Control) have free access to food for 4 weeks. The day feeding (=reverse feeding, RF) animals (RF group) have restricted access to food during daytime (0900-1800) for 4 weeks. After completing the feeding schedules, body weights, testis and epididymis weights of animals from both group were not significantly different. However, the weights of seminal vesicle (control : RF group = $0.233{\pm}0.014g$ : $0.188{\pm}0.009g$, $p$<0.01) and prostate (control : RF group = $0.358{\pm}0.015g$ : $0.259{\pm}0.015g$, $p$<0.001) were significantly lower in RF group animals. The mRNA levels of pituitary common alpha subunit ($C{\alpha}$; control : RF group = $1.0{\pm}0.0699$ AU : $0.1923{\pm}0.0270$ AU, $p$<0.001) and $FSH{\beta}$ (control : RF group = $1.0{\pm}0.1489$ AU : $0.5237{\pm}0.1088$ AU, $p$<0.05) were significantly decreased in RF group. The mRNA levels of ACTH were not significantly different. We were unable to find any prominent difference in the microstructures of epididymis, and there were slight alterations in those of seminal vesicles after 4 weeks of reversed feeding when compared to control samples. The present study demonstrates that the shift and/or restriction of feeding time could alter the pituitary gonadotropin expression and the weights of seminal vesicle and prostate in rats. These data suggest the lowered gonadotropin inputs may decrease androgen secretion form testis, and consequently results in poor response of androgen-dependent tissues such as seminal vesicle and prostate.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.247-252
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• 2005

The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to $40\%$ at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

• The korean journal of orthodontics
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• v.15 no.1
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• pp.141-148
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• 1985

It has been a long time since the cephalometrics was introduced to orthodontic field for diagnosis and treatment planning, but it's main concern was limited to hard, skeletodental tissue. It is well known that perioral and facial soft tissue determine the position of individual teeth and that the abnormality in size and shape of the soft tissue are able to cause malformed occlusion. Because of our lack of knowledge about resultant morphologic changes in the relationship between skeletal pattern and specific pattern of lingual and facial muscles, we can't help setting greater value on only abnormalities of teeth in the skeletal interrelationship. In a point of view that the orthodontist is dealing primarily with muscular structures around the dentition, the tongue, lips, and cheeks, therefore it may be desirable to estimate these structure and their potential influence on the dentition on developmental and time base. The author hit upon on idea of the aspect above, so studied on the intermaxillary space and tongue space and this study used the data from cephalometric films of 33 male and 40 female subject aged from 6 to 11 years of normal Korean children following results were obtained: 1. Means and standard deviation of Korean children were obtained. 2. Yearly increment of each variables were obtained. 3. There is the correlationship more than average among the variables except posterior intermaxillary height item. 4. There are differences between male children and female children in all variables except posterior intermaxillary space item. 5. All variables increased as the age increased except posterior intermaxillary height item of male children.