• 전기화학회지
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• 제25권3호
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• pp.119-124
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• 2022

하이브리드 자동차 및 전기 자동차(하이브리드 및 전기자동차)용 배터리 팩은 고용량 대면적 셀을 적용하기 때문에 배터리 셀의 평균 온도는 중요한 관리 기준이 된다. 최근에는, 배터리 충전시간을 줄이기 위한 고속 충전 기술이 요구되고 있으며, 이에 따른 셀과 전장부품의 발열로 인해 배터리 팩 성능 및 수명의 저하가 발생한다. 따라서, 고속 충전에 따른 배터리 팩의 성능저하를 방지하기 위해 효과적인 배터리 냉각시스템이 필요하다. 본 연구에서는 파우치형 고속 충전용 배터리 셀 적용 냉각시스템 및 모듈 설계를 도출하고 배터리의 효율을 극대화할 수 있는 냉각성능을 분석하였다. 베이퍼챔버 냉각시스템을 적용한 모듈의 온도 편차 분석 결과 모듈 내 온도 편차는 5.82 ℃로 기존 알루미늄 냉각판 대비 낮은 온도를 보여 우수한 냉각시스템 효과를 보였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권2호
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• pp.135-141
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• 2001

Recently, the consumption of soy products has been associated with low rates of hormone-dependent and hormone-independent cancers. Asians, who consume $20{\sim}50times$ more soy per capita than Americans, have lower incidence and death rates from breast and prostate cancer. Because soy contains the isoflavones genistein and daidzein (present as their glycosidic conjugates) at mg/g concentrations, it has been suggested that isoflavones might be acting as natural chemopreventive agents. During the 1980s several groups of investigators carried out experiments to test the effectiveness of soy in the diet in animal models of cancer. These studies reported a protective effect of soy; none showed that soy increased cancer risk. Genistein was shown to inhibit the growth of a wide variety of tumor cell types in culture. The purpose of this study was to evaluate the effects of genistein on the carcinogenesis induced by topical application of 0.5% 9, 10-dimethyl 1,2-benzanthracene (DMBA) on the hamster buccal pouch. 48 syrian hamsters were employed in this study, divided into experimental group and control. 24 animals (DMBA topical application group) had the right buccal pouch painted 3times weekly with 0.5% DMBA in mineral oil, 24 animals (genistein group) were supplied with 0.1mg genistein with DMBA topical application. 3 animals in the experimental group and control were sacrificed at serially each other week after experiments. Their buccal pouches were removed and routinely processed for microscopic examination. The results were as follows: 1. In DMBA topical application and genistein group, they showed carcinogenesis as time goes by experimental stage. 2. Genistein group was retarded in carcinogenesis related to the acanthosis, hyperkeratosis, epithelial dysplasia. 3. p53 immunohistochemical study showed that the p53 protein of genistein group was less expressed than that of the control group. Thus, it seems that genistein has chemopreventive effect on the carcinogenesis in the oral cavity, but further study is required to elucidate the anticancer mechanism of genistein.

• Applied Microscopy
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• 제15권2호
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• pp.98-110
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• 1985

This study was performed to clarify the morphological structures of the epithelia of the renal papilla, renal pelvis and ureter of the sheep (Ovis aries L.) through the light and scanning electron microscopes, Tissue specimens were taken from the renal papilla (common renal papilla and peripelvic column) and the renal pelvis (pelvis proper and pelvic pouch) of the kidney and the ureter. For the light microscopy, tissue blocks were fixed in 10 % neutral buffered formalin and embedded in paraffin wax, serially sectioned at a thickness of $6{\mu}m$. These sections were stained with hematoxylin-eosin and periodic acid-Schiff reaction. For the scanning electron microscopy, tissue blocks were prefixed in 1% glutaral-dehyde-1.5% paraformaldehyde solution and postfixed in 1% osmium tetroxide solution, dehydrated in graded alcohol, transferred to isoamyl acetate, and then dried by the critical point dryer (Polaron E 3000). These dried tissues were coated with gold and observed with a scanning electron microscope (JSM-35C), The results were as follows: The apex of the common renal papilla was lined with simple columnar epithelium having many microvilli on its luminal surface. Lateral portion of the papilla was lined with stratified epithelium $2{\sim}3$ layers thick, and its superficial cells were microvillar cells having many microvilli. The epithelium lining the peripelvic column was $1{\sim}2$ layers thick. The superficial layer was made of the microvillar cells, but a few microplica cells were appeared in the region near the pelvic pouch. The epithelium of the pelvic pouch was $1{\sim}2$ layered transitional type, and its superficial cells were microplica cells. The epithelia of the pelvis proper and ureter were $4{\sim}6$ layered transitional type, and their superficial cells were typical facet cells existing many round depressions and ridges of cell membranes of the luminal side.

• Journal of Electrochemical Science and Technology
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• 제13권2호
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• pp.208-212
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• 2022

In this paper, we report the effects of temperature on the deterioration of graphite-based negative electrodes during the longterm cycling of lithium-ion batteries (LIBs). After cycling 75 Ah pouch-type LIB full cells at temperatures of 45℃ (45-Cell) and 25℃ (25-Cell) until their end of life, we expected to observe changes in the negative electrode according to the temperature. The thickness of the negative electrode of the cell was greater after cycling; that of the electrode of 45-Cell (144 ㎛) was greater than that of the electrode of 25-Cell (109 ㎛). Cross-sectional scanning electron microscopy analysis confirmed that by-products caused this increase in the thickness of the negative electrode. The by-products that formed on the surface of the negative electrode during cycling increased the surface resistance and decreased the electrical conductivity. Voltage profiles showed that the negative electrode of 25-Cell exhibited an 84.7% retention of the initial capacity, whereas that of 45-Cell showed only a 70.3% retention. The results of this study are expected to be relevant to future analyses of the deterioration characteristics of the negative electrode and battery deterioration mechanisms, and are also expected to provide basic data for advanced battery design.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권2호
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• pp.147-154
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• 2002

Genistein that is a component of soy has been reported to have a protective effect on the carcinogenesis of various tumors and to inhibit the growth of a wide variety of tumor cell in vitro. Angiogenesis is an essential process for the carcinogenesis, growth, invasion and metastasis of cancer and genistein has been suggested to act as natural anti-angiogenic agent. The purpose of this study was to evaluate the effects of genistein on the vascular endothelial growth factor (VEGF) expression in hamster buccal pouch oral carcinogenesis model induced by 9, 10-dimethyl 1,2-benzanthracene (DMBA). Experimental group that were supplied with 0.1mg/day genistein were sacrificed by time schedules and routinely processed for immunohistochemical examination of VEGF. In genistein treated group, carcinogenesis was retarded with respect to the acanthosis, hyperkeratosis, and epithelial dysplasia. Immunohistochemical study showed that the VEGF protein of genistein group was less expressed than that of the control group. (p<0.05) Thus, it is postulated that genistein has chemopreventive effect on the oral carcinogenesis, and this chemopreventive effect, at least partly, is originated from the anti-angiogenic effect of genistein

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5753-5757
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• 2012

Apoptosis, also known as cell suicide or programmed cell death, removes unwanted and genetically damaged cells from the body. Evasion of apoptosis is one of the major characteristic features of rapidly proliferating tumor cells. Chemopreventive agents inhibit or suppress tumor formation through apoptotic induction in target tissues. The aim of the present study was to investigate the pro-apoptotic potential of lupeol during 7,12-dimethylbenz(a) anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Topical application of 0.5% DMBA three times a week for 14 weeks in the buccal pouches of golden Syrian hamsters resulted in oral squamous cell carcinoma. The expression pattern of apoptotic markers was analyzed using immunohistochemistry (p53, Bcl-2, Bax) and ELISA reader (caspase 3 and 9). In the present study, 100% tumor formation with defects in apoptotic markerexpression pattern was noticed in hamsters treated with DMBA alone. Oral administration of lupeol at a dose of 50mg/kg bw completely prevented the formation oral tumors as well as decreased the expression p53 and Bcl-2, while increasing the expression of Bax and the activities of caspase 3 and 9. The present study thus indicated that lupeol might inhibit DMBA-induced oral tumor formation through its pro-apoptotic potential in golden Syrian hamsters.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권4호
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• pp.414-434
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• 1997

Though many genetic and epigenetic alterations have been identified in hamster oral carcinogenesis model, there is no information about the possible role of transforming growth factor related with oral cancer. The purpose of this paper was to find the expression patterns of transforming growth factor alpha and beta during the stages of complete oral carcinogenesis model in hamster. 0.5% 9, 10-dimethyl-1, 2-benzanthracene(DMBA) in mineral oil was topically applied to the buccal pouch of 75 hamster three times a week during the experimental periods. The experimental animals were subdivided into two groups of control and experiment. Only the mineral oil was applied to the control group. 0.5% DMBA in mineral oil was applied to the experimental groups of 6, 8, 10, 12, 14, 16, 18 and 20 weeks. The expression of the $TGF-{\alpha}$ and $TGF-{\beta}$ protein were evaluated by the distribution and intensity of positive cells during the carcinogenesis using the immunohistochemical study. The following results were obtained ; 1. The buccal pouch epithelium of hamster was histologically changed to the dysplasia at 6, 8, 10 weeks, carcinoma in situ at 12 weeks, and squamous cell carcinoma at 14 weeks. 2. The expression of the $TGF-{\alpha}$ was restricted to the parabasal and basal layers of the normal and dysplastic mucosa, but those positive cells were extended to the spinous layers of the epithelium in the carcinoma. 3. The degree of $TGF-{\alpha}$ expression was markedly decreased in the carcinoma at 16, 18, 20. The strong positive staining in the center of cancer islands and weak positive staining in periphery of tumor were seen at the stage of squamous cell carcinoma. 4. The positive index of the $TGF-{\alpha}$ had a tendency to increase with DMBA- applied time. There was a statistically significant difference between 12, 18, 20 experimental group and control group (p<0.05). 5. The expression of the $TGF-{\beta}$ was shown at the cytoplasm of all control and experimental groups, and the parabasal and basal layers of the normal and dyslastic mucosa, but it was shown at the basal layers of the epithelium in the carcinoma. 6. $TGF-{\beta}$ was expressed diffusely at 16, 18, 20 experimental group. The strong positive staining in the center of cancer islands and positive staining in periphery of tumor were seen at the stage of squamous cell carcinoma. From the above findings, the expression of $TGF-{\alpha}$ and ${\beta}$ in oral carcinogenesis model seems to have two formal stages, the first being an overexpression step as reaction to uncontrolled growth and the second being one in which external protein accumulate in the surrounding stroma and intracytoplasm. Overexpression of $TGF-{\alpha}$ and ${\beta}$ may have important cooperative roles for the promotion of cancer and factor of prognosis.

• 한국패류학회지
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• 제2권1호
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• pp.26-29
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• 1986

Corbicula fluminea, one of the 2 species in the family Corbiculidae living in the Lake Uiam, was used as an experimental material and the embryonic development and the structure of glochidia of this species were investigated. This freshwater mussels was oviparous, but some ovoviviparous: incubated their youngs in the inner-demibranchs or outer-demibranchs, however, chiefly used the inner-demibranchs as brood-pouch. The average time required from a fertilized egg to two-cell stage, veliger stage, and glochidium was 76 minutes, 3 hours, and 17 hours, respectively, The mean size of glochidium was $168{\mu}m$ in shell height, $195{\mu}m$ in shell lengh, $114{\mu}m$ in hinge legth and the form of glochidium was D-type and had no hooks or hooklets for attaching to fish like Unioidae.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.94.2-94.2
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• 2003

CJ-11668 is a new potent and selective COX-2 inhibitor. CJ-11668 showed COX-2 inhibition (IC50) of 65nM and selectivity ratio (COX-l/COX-2) of 770 in the cell based assay. In the human whole blood assay, CJ-11668 showed COX-2 inhibition (IC50) of 370nM and selectivity ratio (COX-l/COX-2), 135. The treatment of CJ-11668 (5 mg/kg, p.o) produced a significant inhibition (35%) of inflamed rat paw volume in the carrageenan-induced acute inflammation. CJ-11668 also suppressed the PGE2 level (69% inhibition, 1 mg/kg, p.o) in the zymosan-induced mouse air pouch model after 3 hrs. (omitted)

• Investigative Magnetic Resonance Imaging
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• 제23권4호
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• pp.367-373
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• 2019

Yolk sac tumors are rare malignant germ cell neoplasms that usually arise from the gonads. Extragonadal yolk sac tumors (EGYSTs) frequently occur in the mediastinum in post-pubertal females. EGYSTs in the pelvis are extremely rare, and to date, only thirteen cases have been reported in the English literature. Among them, the primary EGYST of the pelvic peritoneum in post-pubertal females has only been reported in ten cases. The present case describes a 26-year-old female diagnosed with primary peritoneal yolk sac tumor located in the rectouterine pouch. We report clinical and tumor imaging features, including ultrasound, computed tomography (CT), magnetic resonance images (MRI), positron emission tomography-computed tomography (PET-CT), and present a review of the literature.