• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.233-236
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• 2006

A dilatometer was used to investigate the effect of cure conditions and the presence of filler in an epoxy system. These studies showed shrinkage in the cured epoxy when heating it through the glass transition temperature region. The magnitude of the shrinkage, related to stress build up in the epoxy during curing, was influenced by the processing conditions, filler presence and the nature of the mold used to contain the resin. Cure and cyclic cure at a lower temperature, prior to a post cure, decreased the magnitude of observed shrinkage. Cure shrinkage decreased with number of cyclic cure. Post cured samples outside the mold led to less shrinkage compared with sample in the mold. And sample containing kaolin filler showed less shrinkage than unfilled sample.

• Journal of Ocean Engineering and Technology
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• v.23 no.4
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• pp.1-5
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• 2009

A dilatometer was used to investigate the effect of cure conditions, mold types and the presence of filler in an epoxy system. These studies showed shrinkage in the cured epoxy when heating it through the glass transition temperature region. The magnitude of the shrinkage, related to stress build up in the epoxy during curing, was influenced by the processing conditions, filler presence and the nature of the mold used to contain the resin. Cure and cyclic cure at a lower temperature, prior to a post cure, decreased the magnitude of observed shrinkage. Cure shrinkage decreased with the number of cyclic cures. Post cured samples outside the mold led to less shrinkage compared with samples in the mold. Sample cured in a silicon mold represented less shrinkage than sample cured in an aluminum mold. Sample containing kaolin filler showed less shrinkage than unfilled sample.

• Journal of Adhesion and Interface
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• v.9 no.3
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• pp.20-26
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• 2008

It is well know that the structure of shape memory alloy (SMA) can change from martensite austenite by either temperature or stress. Due to their inherent shape recovery properties, SMA fiber can be used such as for stress or cure-monitoring sensor or actuator, during applied stress or temperature. Incomplete superelasticity was observed as the stress hysteresis at stress-strain curve under cyclic loading test and temperature change. Superelasticity behavior was observed for the single-SMA fiber/epoxy composites under cyclic mechanical loading at stress-strain curve. SMA fiber or epoxy embedded SMA fiber composite exhibited the decreased interfacial properties due to the cyclic loading and thus reduced shape memory performance. Rigid epoxy and the changed interfacial adhesion between SMA fiber and epoxy by the surface treatment on SMA fiber exhibited similar incomplete superelastic trend. Epoxy embedded single SMA fiber exhibited the incomplete recovery during cure process by remaining residual heat and thus occurring residual stress in single SMA fiber/epoxy composite.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.457-465
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• 2007

In this paper, polymer-modified repair materials using polymer dispersions with six repair methods are prepared with various polymer-cement ratios, and tested for compressive and flexural strengths through each curing condition such as dry cure, water cure, and freezing and thawing cyclic action. And, the adhesive interface between the polymer-modified mortar and mortar substrate is observed by a scanning electron microscope. From the test results, the compressive and flexural strengths of cement mortar repaired by polymer-modified mortar are improved with a rise in the polymer-cement ratio regardless of the type of polymer and curing conditions. Such an improvement in the strengths of polymer-modified repair materials to ordinary cement mortar is explained by the high adhesion of polymer-modified mortar. Strength reduction of polymer-modified repair materials after freezing and thawing cyclic actions is recognized, but it is lower than that of unmodified mortar. Especially, cement mortar repaired by polymer-modified mortar with a St/BA emulsion has good strength properties compared with those of SBR latex and PA emulsion. Accordingly, it is judged that polymer-modified mortars with a St/BA emulsion are possible to use as repair materials to ordinary cement mortar and concrete.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.1
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• pp.176-182
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• 2008

Scolopendra was known to cure erectile dysfunction. This study was aimed to investigate the effects of Scolopendra on the nitric oxide synthase activity, nitrite level, cyclic-GMP and erectile responses in rat's corpus cavernosum penis. The crushed Scolopendra was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 14.2 g. Scolopendra extract was oral-administered 50 mg per 1 kg of body weight for 30 days. First, samples were treated with Scolopendra, and then ethanol-treated rats and L-N-Nitroarginine methyl ester (L-NAME) treated rats were fed with the samples. The level of urethral nitrite and nitric oxide synthase activity in the ethanol-Scolopendra double administered rats were as high as in the normal group, while the one in the ethanol-treated group was decreased. The level of urethral cyclic-GMP and guanylate cyclase actiyity in the ethanol-Scolopendra double administered rats were as high as in the normal group, while the one in the ethanol-treated group was decreased. The level of urethral phosphodiesterase activity in the ethanol-Scolopendra double administered rats was as low as in the normal group, while the one in the ethanol-treated group was increased. The erectile response to a cavernous nerve stimulation in L-NAME $(10^{-4})-treated$ rats was restored by the Scolopendra to the similar level seen in the normal group. The electile response to cavernous nerve stimulation in the ethanol-Scolopendra double administered rats were increased as high as in the normal group while the one in the ethanol-treated group was decreased. Scolopendra was effective in restoring the ethanol-induced or L-NAME-induced erectile dysfunction in rats.

• Journal of Pharmacopuncture
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• v.22 no.3
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• pp.131-139
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• 2019

Introduction: Mastalgia is the most common benign breast disorder during the fertility period of women. So far a wide range of natural or complementary medicines is used to cure mastalgia. Sanitary organizations need complete and suitable details to help women, for making the proper decision for alternative treatment based on the evidence. The aim of the present study is to introduce medicinal plant-based treatments about mastalgia and summarizes clinical trials about this disorder. Method: The articles were provided using mixture of keywords including cyclic pain, breast, treatment, therapeutics, therapy, clinical trial, herbal, drug, mastalgia and all the probable terms, in national and international databases SID, Iran Medex, Magiran, PubMed, Scopus, Medline, Science direct and Cochrane library, in both Persian and English languages. All cross-sectional and review articles about herbal treatment of mastalgia until 2018 November were studied. Results: Nineteen articles from all of the available articles (45 cases) and a sample size about of (1987 cases) were included in our study. The articles were clinical trials. The results revealed that mastalgia could be healed by Nigella sativa, Vitex agnus-castus, curcumin, Hypericum perforatum, Citrus sinensis, wheat germ, and Ginkgo biloba. Conclusion: Most of the evaluated medicinal plants possessing antioxidant compounds with anti-inflammatory and analgesic properties, exhibited healing effects in the treatment of mastalgia. Thus, medicinal plants can be considered in the treatment of mastalgia; however, further investigations are needed to obtain more details about their probable side effects.

• Journal of Pharmacopuncture
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• v.24 no.1
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• pp.32-40
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• 2021

Objectives: Pathogenic microbes are causal agents for various types of severe and even lethal infectious diseases. Despite of development in medication, bacterial and fungal infections still persist to be a vital problem in health care. Bacteria and several fungal species have shown resistance to antibiotics used in treatment to current medications. Therefore, it is a considerable field of interest in the design and development of novel compounds with antimicrobial activity. Methods: The compounds bearing a heterocyclic ring play an imperative role among other organic compounds with pharmacological activity used as drugs in human for control and cure of various infections. Thiadiazoles containing nitrogen-sulfur atom as part of their cyclic structure which shown wide-ranging application as structural units of biologically active molecules and are very useful intermediates in Medicinal Chemistry. Results: The effectiveness of the thiadiazole nucleus was established by the drugs currently used for the treatment of various infections. 1,3,4-Thiadiazoles and some of their derivatives are widely studied because of their broad spectrum of pharmacological activities. Conclusion: In the present work, a series of 1,3,4-Thiadiazole derivatives were synthesized by cyclization of a group of various benzaldehyde with thiosemicarbazide in the presence of various reagent like FeCl3, HCHO by losing a molecule of water. These derivatives were found to possess prominent antimicrobial activity.

• 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.