• Composites Research
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• v.18 no.6
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• pp.1-8
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• 2005

The fiber-reinforced composite materials have been advanced for various applications because of their excellent mechanical and electromagnetic properties. On their manufacturing processes, however, thermo-curing inherently produces the undesired thermal deformation mainly from temperature drop from the process temperature to the room temperature, so called spring-back. The spring-back must be understood especially in the hybrid composites in order to design and fabricate desired shape. In this research, (glass fiber / epoxy) + (carbon fiber / epoxy) unsymmetric hybrid composites were fabricated under various conditions such as cure cycle, laminate thickness, stacking sequence and curing sequence. Coupons were made and spring-back were measured using coordinate measuring machine (CMM). Using the Classical Lamination Theory (CLT) and finite element analysis (ANSYS), the behavior of spring-back were predicted and compared with the experimental data. The results from CLT and FEA agreed well with the experimental data. Although, the spring-back could be reduced by lowering curing temperature, at any case, the spring-back could not be removed completely.

• Polymer(Korea)
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• v.24 no.6
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• pp.845-853
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• 2000

The optimum cure cycle and carbonization condition were selected by the DSC and TGA analysis and green bodies were prepared by the method of hot press molding and then carbonized up to 140$0^{\circ}C$. Additives such as graphite powder, carbon black, milled carbon fiber and carbon fiber mat, which were considered to be effective in improving the interlaminar shear strength, were also added to check their effects on the density and porosity of products. Then, their relations with mechanical properties such as ILSS and flexural strength were investigated. The composites added 9 vol% of graphite powder showed the greatest values of ILSS and flexural strength. Otherwise, in case of adding carbon black, the composites showed the slight improvement of ILSS at its contents of 3 vol% but the flexural strength was decreased. When milled carbon fiber and carbon fiber mat were added, the lack of resin and the heat shrinkage during the carbonization caused the delamination, resulting in decreasing the density, ILSS and flexural strength.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1666-1672
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• 2005

Oriental medicinal drugs have a broad spectrum of clinical use for the cure of nervous system diseases including brain ischemic damages or neuropathies. Yet, specific drugs or drug components used in the oriental medicine in relation to none fiber regeneration are not known. In the present study, possible growth promoting effects of oriental medicinal drugs were investigated in the injured sciatic nerve system in the rat. By immunofluorescence staining, we found that Jahageo (JHG, Hominis placenta) increased Induction levels of axonal growth associated protein GAP-43 in the rat sciatic none. Small growth promoting activity was found in Golsebo (GSB, Drynariae rhizoma) and Baikhasuo (BHSO, Polygoni multiflori radix) drugs. JHG also increased cell cycle protein Cdc2 levels in the injured area of the sciatic nerves. Immunofluorescence staining indicated that induced Cdc2 protein was mostly localized in the Schwann cells in the injury area, implying that JHG activity might be related to increased Schwann cell proliferation during axonal regeneration. Moreover, levels of phospho-extracellular signal-regulated (ERK) pathway in the injured neNes were elevated by JHG treatment while levels of total ERK were unaltered. In vivo measurement of axonal regeneration using retrograde tracer showed that JHG, GSB and BHSO significantly enhanced Dil-labeled regenerating motor neurons compared with saline control. The present data suggest that oriental medicinal drugs such as JHG, GSB, and BHSO may be a useful target for developing specific drugs of axonal regeneration.

• The Journal of the Korea Contents Association
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• v.15 no.5
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• pp.592-606
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• 2015

Depression and mental illness across all age groups, and steady increasing in suicide rate are our major social problems which cause dramatically decreasing government competitiveness. While Korean government has implemented various policies to improve mental health and prevent suicide, it faces revealing issues in progress on implementation and referral management systems. The current research examined domestic and foreign cases to understand the actual status and directivity of ICT convergence plan in terms of mental health. The United States and the United Kingdom have provided convergent ICT service, telepsychiatric care to senior citizens in rural areas, children and adolescents, socially disadvantaged class, etc. In Korea, emergency-notice devices are installed to prevent suicide for single elderly people, and diverse mobile health devices are developing to cure depression and Alzheimer's disease. ICT convergent mental health care service is needed to save socioeconomic costs and realize universal welfare for an aging society. Social consensus on sharply conflict issues, medical law and medical devices about telepsychiatry service, effectiveness studies on users' unique psychiatric characteristics by life cycle, and region-specialized strategies for the least densely populated rural regions with lower access to medical care should be considered.

• Polymer(Korea)
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• v.24 no.3
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• pp.350-357
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• 2000

Curing behaviors of glass/epoxy prepreg for printed circuit boards (PCB) were studied by using dielectrometer and differential scanning calorimeter. This prepreg was showed the lowest ionic viscosity at about 115$^{\circ}C$, and then the ionic viscosity was gradully increased up to 15$0^{\circ}C$. This indicated that the curing reaction of this prepreg started at 115$^{\circ}C$ and the molecular weight was increased by the accelerated thermal cross-linking reaction. The loss factor and tan $\delta$ values were also measured and discussed. The dielectric behaviors of this prepreg system were also measured according to the cure cycle for PCB. This material was found to be thermally stable up to about 30$0^{\circ}C$ and then was showed an abrupt decomposition beyond this temperature.

• Journal of Life Science
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• v.22 no.11
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• pp.1571-1586
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• 2012

On earth, there are about 5,400 kinds of mammals, of which about 1,000 kinds are herbivores. Among herbivores, about 250 kinds are known to be ruminants. As for cattle and sheep, which are ruminants, fermentation takes places mainly in their rumen; in contrast, for pigs and men, which are non-ruminants, fermentation takes place mainly in their caecum, colon, and rectum. As for the kind and dominance of rumen microorganisms, Bacteroidetes account for 51% and Firmicutes for 43%. As for the dominance of the large intestine microorganisms in men, Firmicutes account for 65% and Bacteroidetes for 25%. Cell wall components are decomposed by microorganisms, and short chain fatty acids (SCFAs) are generated through fermentation; the ratio of acetate, propionate, and butyrate generate is 60:25:15. Butyrate absorbed through the primary butyrate transporter MCT1 (mono carboxylate transports-1) in the intestines activates such SCFA receptors as GPR43 and GPR41. Butyrate has a strong anti-tumorigenic function. Butyrate is characterized by the fact that it has an effect on many cancer cells, contributes to the coordination of functions in the cells, and induces cancer apoptosis. Butyrate activates caspase but inhibits the activity of HDAC (histone deacetylase), so as to induce apoptosis. In addition, it increases p53 expression, so as to induce cell cycle arrest and apoptosis. Anti-inflammation actions of SCFA include the reduction of IL-8 expression in intestinal epithelial cells, the inhibition of NO synthesis, and the restraint of the activity of NF-${\kappa}B$ (nuclear factor ${\kappa}B$), so as to suppress the occurrence of cancers caused by inflammation. Butyrate plays an important role in maintaining physiological functions of intestinal mucous membranes and is used as a cure for inflammatory bowel disease (IBD).

• Korean Journal of Head & Neck Oncology
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• v.22 no.2
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• pp.130-136
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• 2006

Introduction : The sensitivity of tumor cells to radiotherapy is a critical determinant of local control and potential cure in advanced head and neck squamous cell carcinoma(HNSCC). The emergence of radioresistant tumor cells is an obstacle to cancer therapy. Most radioresistant cells have a higher proportion of cells in the Sphase of the cell cycle and a lower apoptotic fraction than radiosensitive cells. HSV replication is increased in cells that have higher S-phase fractions. NV1066 is an oncolytic herpes simplex virus type-1 mutant. We hypothesized that NV1066 replication and cytotoxicity are increased in radioresistant cells. The purpose of this study is to evaluate the antitumor efficacy of NV1066 to treat radioresistant HNSCC. Methods : Radioresistant cells were selected by treating five HNSCC cell lines with repeated conventional fractionated doses of radiation(2Gy/day), using a Cs-137 irradiator, up to a cumulative dose of 70Gy. Clonogenic cell survival and S-phase fractions were compared between radioresistant and parental radiosensitive cells. The two cell populations were then treated with NV1066 to examine viral replication, by the viral plaque assay and viral cytotoxicity. Results : Fractionated irradiation resulted in the selection of radioresistant cells. Radioresistant cells had a higher S-phase fraction(42.9%) compared to parental cells(26.2%). NV1066 replication in radioresistant cells was 7.4 times higher than in parental cells(p<0.01). Treatment with NV1066 resulted in increased cytotoxicity of 24.5% in radioresistant cells compared to parental cells(p<0.05). Conclusion : NV1066 showed increased viral replication and cytotoxicity in radioresistant HNSCC cell lines. These findings suggest a potential clinical application for this oncolytic viral therapy as treatment for radioresistant head and neck cancers.

• Journal of Korean Medical Ki-Gong Academy
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• v.11 no.1
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• pp.236-261
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• 2009

'Jeom-hyeol-gigong(點穴氣功)' gives a drill, Gi(氣) as a place to jam. This pathogen(邪氣) is removed. Given the low places and supplement it energy to flow up the well is the cure. This is an internal organ and muscular Gi allows a natural flow. Blood, one that moves and guides Gi is Gi I still feel that it makes any blood, making you feel good in life is flowing with vitality. Gi driving our whole body, while supplying vital energy and blood circulation, helping to defend the body is functioning. 'Jeom-hyeol-gigong' principle of Gi where the blockages to flow naturally energy is to let the flow. Aura of the voluntary and proactive action will be to have healthy bodies. Gi as a whole-body blood circulation leading to the cells in each tissue to supply energy and nutrients to every cell as the original principles of free activities that will maximize your life. Gi to prevent the three causes Internal causes: 5 greed and 7 emotions External causes: climate, food, pathogens, stress, etc. The internal nor the external causes: internal and external factors that cause the complex elements, incorrect position of the bone caused by an imbalance Heart disease will be police officers and raise their resistance to disease than the body, what jung-gi(正氣) have to develop. Beneficial to human body's resistance to raise the jung-gi people young-gi(營氣) and wi-gi(衛氣) should be enhanced. If the form is perfectly possible, Gi cycle itself should not have to breathe. Abdominal diagnosis 'bok-su-ap-an-beop(伏手壓按法)', 'sam-ji-tam-an-beop(三指探按法)' hands are like this, which outlined five viscera in order to understand the problem, the lower side of the clavicle (lung), the pit of stomach (Heart), both the lower ribs (liver), navel below (kidney) can be diagnosed at such areas. In each area of the skin, abdominal muscle tension, aching, or pressing a fuss about, beating the ruling of the state and the problem is a clue. And mo-hyeol(募穴) and certain Acupressure group, the chest, back, belly, so that scattered around each' book 'of the problem can be found. This is also the target of such a diagnosis, such as shape, color of skin, muscle Mostly the scope of the pitch in the cervical spine is broad across the hips. sugi(手氣) method that 'an method(按法) and 'ma method(摩法), bak method(拍法) is.

• Molecules and Cells
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• v.38 no.3
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• pp.221-228
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• 2015

Because Schwann cells perform the triple tasks of myelination, axon guidance and neurotrophin synthesis, they are candidates for cell transplantation that might cure some types of nervous-system degenerative diseases or injuries. However, Schwann cells are difficult to obtain. As another option, ectomesenchymal stem cells (EMSCs) can be easily harvested from the nasal respiratory mucosa. Whether fibrin, an important transplantation vehicle, can improve the differentiation of EMSCs into Schwann-like cells (SLCs) deserves further research. EMSCs were isolated from rat nasal respiratory mucosa and were purified using anti-CD133 magnetic cell sorting. The purified cells strongly expressed HNK-1, nestin, $p75^{NTR}$, S-100, and vimentin. Using nuclear staining, the MTT assay and Western blotting analysis of the expression of cell-cycle markers, the proliferation rate of EMSCs on a fibrin matrix was found to be significantly higher than that of cells grown on a plastic surface but insignificantly lower than that of cells grown on fibronectin. Additionally, the EMSCs grown on the fibrin matrix expressed myelination-related molecules, including myelin basic protein (MBP), 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and galactocerebrosides (GalCer), more strongly than did those grown on fibronectin or a plastic surface. Furthermore, the EMSCs grown on the fibrin matrix synthesized more neurotrophins compared with those grown on fibronectin or a plastic surface. The expression level of integrin in EMSCs grown on fibrin was similar to that of cells grown on fibronectin but was higher than that of cells grown on a plastic surface. These results demonstrated that fibrin not only promoted EMSC proliferation but also the differentiation of EMSCs into the SLCs. Our findings suggested that fibrin has great promise as a cell transplantation vehicle for the treatment of some types of nervous system diseases or injuries.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.139-145
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• 2005

Gastric cancer is the most prevalent cancer in Korea and comprises the second cause of cancer death. Surgery only can provide chance of cure, but most locally advanced cancers recur after a curative resection, even though important advances in the surgical and nonsurgical treatments of gastric cancer have taken place. Preoperative chemotherapy theoretically can provide the advantages of reducing the bulk of tumor, which might improve the R0 resection rate, and of treating micrometastases early. Also, preoperative chemotherapy is expected to render unresectable tumors resectable without increasing postoperative morbidity and mortality. There are many new chemo-therapeutic agents available for the treatment of advanced gastric cancer, but still the most effective agent, the optimal time and number of cycle for administration are still not known. The addition of postoperative chemotherapy through an intraperitoneal route and/or radiotherapy might affect the outcome of surgery favorably, but that hasn't been proved yet. A multicenter prospective randomized phase III trial should be peformed to answer for those questions and to improve the curability of gastric cancer treatment.