• Magazine of the Korean Society of Agricultural Engineers
• /
• v.17 no.3
• /
• pp.3878-3884
• /
• 1975

This study was carried out to develop the throw-in type thresher with its size as small as possible. Developing the smallest possible size of the throw-in type thresher has been very important to increase mobility and to reduce the machine price. The thresher that developed for this purpose was tested as to threshing and separation performance for the samples collected in eight catch boxes under the concave while threshing. The amount of grain collected in each compartments was measured and the threshing and separating pattern along the total span of the threshing drum was determined. The performance of separating and threshing units of the test thresher and threshing loss was evaluated by use of the developed grain separating apparatus and the method for measuring the grain separating performance of threshers. The results are summarized as follows; 1. The unthreshed grain (drum losses) and semi-threshed grain did not appeared at all throughout the treatments. 2. When threshed by making use of the developed throw-in type thresher, the threshing grain loss at about 25 per cent grain moisture was about one-half when threshed at about 18 per cent grain moisture. 3. And its grain separating loss in higher feed rate was decreased in comparison with that of lower feed rate. These results suggests that the throw-in type thresher may be suitable for wet threshing and for higher feed rate of threshing. 4. Above 60 per cent of total grain passing through concave fell through the screen within a scant 30 cm from the feeding inlet. This threshing pattern may suggest that major threshing action may be finished before about one third of cylinder length. The required separating load extended over the whole drum span is so defferent that separating elements should be redesigned so as to accomodate this variable pattern of separation load. 5. It was apparent from the experiment that the length of the threshing drum of the throw-in type thresher could be reduced from 1285mm to about 1050mm without increasing grain separation loss greatly.

• The Korean Journal of Physiology
• /
• v.8 no.1
• /
• pp.55-65
• /
• 1974

The effect of ginseng on the ATPase activity of rabbit ref cell membrane has been investigated. The experiments were also designed to determine whether the components of ginseng could be attributed to the effect on ATPase activity which dependent upon sodium plus potassium and is sensitive to ouabain. The following results were observed. 1. The activity of the $Na^{+}-K^{+}-ATPase$ from red cell membrane is stimulated by ginseng, and the concentration of ginseng for half-maximal activity is about 15 mg%. The pH optimum for the ginseng sensitive component is 7.6. 2. The portion of the enzyme activity stimulated by ginseng is completely abolished by ouabain. 3. The activating effect of ginseng on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but activity ratio is decreased. 4. The activating effect of ginseng on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but the activity ratio is decreased. 5. The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts and the rate of activity by ginseng is constant. 6. The action of ginseng on the ATPase activity was not related to the sulfhydryl group of cysteine, the amino group of lysine, the imidazole group of histidine, the quanidinium group of arginine, the carboxyl group of aspartic acid, or the hydroxyl group of threonine. 7. The activating effect of ginseng on the ATPase activity may be not due to a saponin which is contained in ginseng.

• Microbiology and Biotechnology Letters
• /
• v.14 no.5
• /
• pp.407-413
• /
• 1986

In an agitated bead reaction system, the enzymatic saccharification of uncooked starch was substantially enhanced. The enhancement mechanism was investigated front the view of the structural aspect of starch. The mechanical impact caused by the movement of the attrition-milling media resulted neither the destruction of microcrystalline structure nor the fragmentation of starch granule. instead, the most distinct phenomenon was the swelling of starch granule up to about 2.5 times, and the swelling mechanism was not similar with that caused by cooking. However, in the case of the enzyme addition in the attrition coupled reaction system, the swollen starch was easily fragmented into the large number of small particles by the synergistic action of the enzyme and milling-media. The exposed surface area of the fragmented particles plays the major role in enhancing the saccharification. The saccharification rate was quite different depending on the source of starch, the reason was discussed in terms of the granular structure of uncooked starches.

• Microbiology and Biotechnology Letters
• /
• v.20 no.5
• /
• pp.511-518
• /
• 1992

We subcloned a 58 KD chitinase gene of Serratia marcescens into Escherichia coli and investigated the expression and secretion of the chitinase. Chitinase was produced in E. coli by using its own promoter but the levels of enzyme were very low, less than 5 mU/m$\ell$. However, by the combined action of the chitinase and lac promoters, the chitinase activity increased up to about 80 mU/m$\ell$. The most of the chitinase produced in E. coli was localized in periplasm and the small amounts were observed in cytosol and culture medium. Intracellular chitinase activities increased in proportion to the growth of E. coli up to the early stationary phase but rapidly decreased thereafter, which was assumed to be degradation of the chitinase by E. coli proteolytic enzymes.

• 보존과학연구
• /
• s.34
• /
• pp.84-99
• /
• 2013

There are more than 2,900 different species of termites in the world, and just there are 23 species in Japan. They caused more severe infestation compared with Korea. When a structure has become infested with termites, it is important that appropriate action must be taken: the chemical pest control (fumigation, soil termiticide treatment, bait system etc.) or the non-chemical pest control (low oxygen treatment, carbon dioxide treatment, high/low temperature treatment etc.). Especially, there were attempts to make practical protocol of various alternatives since the fumigant(methyl bromide) had been phased out in 2005 in Japan, and practically non-chemical methods would be effective alternatives for some cases, where the scale of infestation is small and limited and when long treatment is possible. But most of all, it is important that the process of pest control is made according to each species of termites with consideration for different characteristics of termites.

• International Journal of Oral Biology
• /
• v.45 no.3
• /
• pp.115-125
• /
• 2020

Resveratrol has been reported to exert anticancer activity via modulation of multiple pathways and genes. In this study, we examined the effect of resveratrol on YD-10B human oral squamous cell carcinoma cells and its molecular mechanisms of action. We found that resveratrol inhibited the proliferation of YD-10B cells in a dose- and time-dependent manner. The suppressive effect of resveratrol was accompanied by a reduction in Bmi-1 gene expression. We observed that silencing the Bmi-1 gene by small interfering RNA effectively downregulated the levels of GLUT1 mRNA and protein, which were also repressed by resveratrol. Bmi-1 silencing increased the number of YD-10B cells in S-phase arrest by approximately 2.3-fold compared with the control. In conclusion, the results of the present study demonstrate, for the first time, that resveratrol suppresses Bmi-1-mediated GLUT1 expression in human oral squamous cell carcinoma cells and suggest that the specific molecular targeting of Bmi-1 and/or GLUT1 expression can be combined with a chemotherapeutic strategy to improve the response of oral cancer cells to resveratrol.

• Animal cells and systems
• /
• v.11 no.2
• /
• pp.129-134
• /
• 2007

The initiation of eukaryotic DNA replication requires assembly of the pre-replicative complex (Pre-RC) through the concerted action of Orc, Cdc6, Cdt1 and Mcm2-7 complex during G1 phase. The pre-RC assembly licenses individual replication origins for the initiation of DNA replication and sufficient number of the pre-RC is essential for proper progression of S phase. However, it is not well known how cells recognize the completion of the pre-RC assembly before G1-S transition. In order to understand the cellular responses to the defects in pre-RC assembly, we depleted the known components of pre-RC proteins using the small interference RNAs in HeLa cells. Although the defects of pre-RC assembly by the depletion of the pre-RC proteins such as Orc2, Cdt1, Mcm2 & Mcm10 did not elicit the activation of Chk1- or Chk2-dependent checkpoint pathways, these cells still showed significant decrease in the cellular level of Cdc25A proteins. These results suggests that a novel checkpoint pathway exist in HeLa cells, which is not dependent upon Chk1 or Chk2 proteins and play essential roles in the cellular responses to the defects in the pre-RC assembly. Also, among those four proteins tested in this study, the depletion of Mcm10 and Cdt1 proteins significantly increased the apoptotic cell death in HeLa cells, suggesting that these proteins not only play roles in the pre-RC assembly, but also are involved in the checkpoint responses to the defects in the pre-RC assembly.

• Structural Engineering and Mechanics
• /
• v.20 no.5
• /
• pp.505-526
• /
• 2005

The influence of the inter-story structural pounding on the seismic behaviour of adjacent multistory reinforced concrete structures with unequal total heights and different story heights is investigated. Although inter-story pounding is a common case in practice, it has not been studied before in the literature as far as the authors are aware. Fifty two pounding cases, each one for two different seismic excitations, are examined. From the results it can be deduced that: (i) The most important issue in the inter-story pounding is the local effect on the external column of the tall building that suffers the impact from the upper floor slab of the adjacent shorter structure. (ii) The ductility demands for this column are increased comparing with the ones without the pounding effect. In the cases that the two buildings are in contact these demands appear to be critical since they are higher than the available ductility values. In the cases that there is a small distance between the interacting buildings the ductility demands of this column are also higher than the ones of the same column without the pounding effect but they appear to be lower than the available ductility values. (iii) It has to be stressed that in all the examined cases the developed shear forces of this column exceeded the shear strength. Thus, it can be concluded that in inter-story pounding cases the column that suffers the impact is always in a critical condition due to shear action and, furthermore, in the cases that the two structures are in contact from the beginning this column appears to be critical due to high ductility demands as well. The consequences of the impact can be very severe for the integrity of the column and may be a primary cause for the initiation of the collapse of the structure. This means that special measures have to be taken in the design process first for the critically increased shear demands and secondly for the high ductility demands.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.21
• /
• pp.9211-9216
• /
• 2014

CXCR7 is involved in tumor development and metastasis in multiple malignancies. However, the function and molecular mechanisms of action of CXCR7 in human cervical cancer are still unclear. In the present study a loss of-function approach was used to observe the effects of recombinant CXCR7 specific small interfering RNA pBSilence1.1 plasmids on biological behavior including proliferative activity and invasive potential, as indicated by MTT assays with the cervical cancer SiHa cell line in vitro. Reverse transcription polymerase chain reaction and Western blotting revealed that CXCR7 was downregulated in transfected compared with control cells, associated with inhibited cell growth, invasiveness and migration. The expression of CXCR7 and CXCL12 was also determined immunohistochemically in 152 paraffin-embedded, cervical squamous cell carcinoma (CSCC) and cervical intraepithelial neoplasia (CIN), or normal cervical epithelial to assess clinico-pathological pattern and CXCR7 status with respect to cell differentiation and lymph node metastasis in Uighur patients with CSCC. CXCR7 and CXCL12 expression was higher in cervical cancer than CIN and normal cervical mucosa, especially in those with higher stage and lymph node metastasis. CXCL12 appeared to be positively regulated by CXCR7 at the post-transcriptional level in CSCC. We propose that aberrant expression of CXCR7 plays a role in carcinogenesis, differentiation and metastasis of CSCC, implying its use as a potential target for clinical biomarkers in differentiation and lymph node metastasis.

• Journal of The Korean Association For Science Education
• /
• v.1 no.1
• /
• pp.73-88
• /
• 1978

The survey is intended to improve science education by the analysis of problems produced in the following nine aspects (objectives, contents, materials, inquring methods, teaching methods, teachers, children, evalutions, admininative supports) during the past five years often the revision of new science curriculum. 1. View for science education. 1) The teacher's and children's view for science education can be seen renewed, being different from the old one. 2) Inquring method in learning and teaching began to take firm root and children came to know that it is the only way to study science. 3) Writers think that the new science education has stepped into the stage of being fixed to a considerable degree. 2. The aspect of administrative policy. 1) The amount of materials in possession is small and the present materials are lacking in solidity and precision. 2) Class room teacher's over load with miscellaneous things is a difficult problem to solve. 3) The shortage of the printed materials and books for children and teachers has an influence on the development of inquring method. 4) It causes cramming to examine all children at the same time by paper test. 5) It is more desirable to appoint qualified teacher only for science teaching. 3. Contents of science curriculum. 1) In current science textbooks. There can be found some contents which are difficult for teachers to understand and not in accordance with the reality of Korea. Therefore, it is imperative that contents of science textbooks should be reexamined. 2) As it is hard to teach concepts of reciprocal action and to prepare materials with teaching of the system of biological concepts, the teaching of contents is likely to be a cramming. 4. The aspect of in-service education. 1) It is obsolutely predominant reation that in-service education is making a great contribution to class room teaching. 2) As adiministrators' policy for science education has a great effect, in-service education for their enlightenment is needed.