• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제31회 추계학술대회논문집
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• pp.239-242
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• 2008

원통형 형상의 연료 그레인을 적용한 하이브리드 추진 시스템에서 연료포트 초기 직경에 따른 연소특성을 고찰하였다. 산화제에 따라 달라지는 연료포트 직경에 따른 연소특성 변화를 알아보고자 산화제로는 GOX와 $GN_2O$를 적용하였고, 고체연료로는 PE를 적용해 실험을 수행하였다. 동일 산화제 유량에서 산화제와 상관없이 고체연료의 초기 포트직경이 커짐에 따라 연소량이 감소함을 확인했고, 산화제로 $GN_2O$를 적용한 경우가 산화제로 GOX를 적용한 경우보다 연료포트 초기 직경에 따른 연소량 차이가 줄어듦을 확인하였다.

• Membrane and Water Treatment
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• 제14권3호
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• pp.107-114
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• 2023

Graphene oxide (GO) membranes have attracted extensive attention in water treatment and related fields. However, GO films are unstable and have low permeability, which have hindered their further development. In this paper, a simple and effective method was used in which GO and single-layer graphene (GN) were mixed, and the layer spacing was effectively controlled by accurately controlling the ratio of GO to GN. GO-GN composite membranes have excellent stability, salt rejection (95.4%), and water flux (26 L m^-2 h^-1 bar^-1). This unique design structure can be used for precise and effective regulation of the layer spacing in GO, improving the rejection rate, and increasing water flux via the enhancement of low-friction capillary action. The rational development and use of this unique composite membrane provides a reference for the water treatment field.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.348-353
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• 1999

Ten Australian Stock Horses colts (five yearling and five 3-year old colts) of which 2 yearlings and 2 three year old colts served as control animals while 3 yearlings and 3 three year old colts received two GnRH immunizations within 4 weeks interval were used in this study. By the 5th to 6th week after immunization, the GnRH antibody titres in the plasma rose above 1:1000 and attained peak levels of 1:6500 by the 8th week and gradually declined to about 1:3000 by the 10th week in both the age groups. The testosterone and androstenedione concentrations of the control colts in both age groups were significantly greater (p<0.05) than that of the vaccinated groups. During the immunosuppression period, the vaccinated colts behaved like geldings. Semen could not be collected from 2 of the 3 three-year old vaccinated colts. The testicular dimensions, testicular weight, parenchymal weight, seminiferous tubule volumes, interstitial space volumes, Leydig cell volume, seminiferous tubule % of the control colts were significantly greater than those of the vaccinated colts in both the age groups. The 3-year old control colts had a significantly (p<0.05) greater % of Leydig cells than the control and vaccinated 1-year old colts. There was arrest of spermatogenesis with complete absence of sperm in the testes of the vaccinated colts while there was various stages of spermatogenesis in those of the control colts. Morphometric analysis demonstrated that the 3-year old colts had significantly (p<0.05) greater DSP/gm of testis and DSP/testis than those of the 1-year old control colts. This study elucidated that the GnRH immunization could suppress the testicular function of the 3-year old and yearling colts.

• 한국초전도ㆍ저온공학회논문지
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• 제17권3호
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• pp.33-36
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• 2015

A liquid nitrogen ($LN_2$) is usually used to be a coolant and insulant for a HTS coil system. HTS wires for a superconducting apparatus may be surrounded by gaseous nitrogen ($GN_2$) due to film boiling generated by a quench or voids occurred by electrical breakdown. The increased maximum electric field intensity at $GN_2$ may result in the degradation of dielectric strength of a HTS coil system. In this paper, a study on the dielectric characteristics of a composite insulation system composed of $LN_2$ and $GN_2$ is performed. A sphere-to-plane electrode system made with stainless steel is used to perform the experiments under AC and lightning impulse voltage condition. A sphere electrode is surrounded by $GN_2$ and a plane electrode is immersed into $LN_2$ to conduct dielectric experiments with a composite insulation system. The dielectric experiments are performed according to the level of $LN_2$ from the plane electrode to a sphere electrode. It is found that the dielectric characteristics of a composite insulation system are dependent on the level of $LN_2$ and the field utilization factor of an electrode system.

• Childhood Kidney Diseases
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• 제17권1호
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• pp.1-5
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• 2013

사구체에 면역글로불린은 음성이면서 C3 만 침착되는 경우, 다른 원인이 없는 경우 C3GN을 의심하여야 한다. 광학현미경으로는 세포의 증식이 있는 경우와 없는 경우가 있지만, 전자현미경으로는 EDD가 내피세포 밑으로 혹은 메산지움 등에 침착함을 확인하여야 한다. 대체보체경로의 조절이상이 원인임으로 혈청 C3 치를 비롯하여 CFH, CFI, CFB 등을 측정하여야 하며, C3 nephritic factor, anti-factor H 자가항체 등을 조사하는 것이 필요하다. 보체 조절이상을 일으키는 유전자 돌연변이를 조사해 보아야 한다. 예후는 안정적이지만, 치료는 대증적이다. 이론적으로 보체의 활성화를 저지하는 약으로 가능할 것으로 생각되며, C5 항체인 eculizumab으로 치유된 보고도 있다.

• 한국임상수의학회지
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• 제22권4호
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• pp.428-430
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• 2005

A female French Bulldog was referred to Veterinary Medical Teaching Hospital, Chungbuk National University. In case, alopecia and erythema nodosum were the main complaints in a 16 months old female dog. Ventral alopecia and dorsal erythema nodosum have been presented on skin lesions for 8 months. There were no specific change with CBC and blood chemistry but plasma estrogen concentration was 68 pg/ml and cornified superficial epithelial cells were detected above $90\%$ by cytology examination of vaginal smear preparation. Ovarian cyst was detected by ultrasonography in the left ovary. Cystic diameter was $14.2\times12.0mm$. Therefore, we diagnosed as unilateral multiple follicular cysts. The dog was treated with GnRH $50{\mu}g$ injection by intramuscularly Cyst size was decreased $7.3\times7.2mm$ after 7 days GnRH treatment and disappeared after 14 days GnRH treatment. Also dermatitis by unilateral multiple follicular cysts were recovered after 21 days GnRH treatment.

• 한국발생생물학회지:발생과생식
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• 제16권1호
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• pp.31-38
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• 2012

Kisspeptin has been implicated in the process of puberty onset in various animal groups. This peptide is encoded by a gene, Kiss1 in avian and mammalian species. Contrary to these higher vertebrates, however, fish appeared to have another gene, Kiss2 that also codes for the precursor peptide of kisspeptin. To figure out biological significance of this gene during the puberty onset in fish, the expression profile of Kiss2 gene was investigated in the brain of Nile tilapia together with genes of GPR54, GnRH receptorI (rGnRHI) and GTH subunits ($LH{\beta}$ and $FSH{\beta}$). Expression of Kiss2 mRNA significantly increased at 2 weeks post hatch (wph) and 13 wph ($P$<0.05). This increase coincided with the increases of GPR54 and rGnRH I gene expression. Detection of $LH{\beta}$ and $FSH{\beta}$ subunit gene expression was possible later than 13 wph, indicating the activation of gonadotrophs in the pituitary. Data obtained from this study strongly suggest that, in addition to Kiss1 gene, Kiss2 gene is deeply associated with the onset of puberty by the activation of hypothalamus pituitary gonadal axis in Nile tilapia.

• 전기학회논문지P
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• 제63권4호
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• pp.356-360
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• 2014

The environmental pollution caused by green-house gases such as $SF_2$ has been becoming the main issue of industrial society. As a part of these efforts, 180 countries signed the Kyoto Protocol in 1997 to cut back on their green-house gas emissions [1]. Therefore, a study on the dielectric characteristics of the $GN_2$ is important for designing a eco-friendly high voltage apparatuses. In this paper, to develop an electrically reliable, stable, and eco-friendly high voltage apparatus, the breakdown voltage and partial discharge inception voltage characteristics in $GN_2$ considering utilization factors are studied for the establishment of insulation design criteria of an high voltage apparatus. Dielectric experiments are performed by using several kinds of sphere-plane electrode systems made of stainless steel. Also, the dielectric characteristics of the $GN_2$ are analyzed by using a Finite Elements Method (FEM) according to various field utilization factors. The results are expected to be applicable to designing the high voltage apparatuses using $GN_2$ as an insulation gas.

• Childhood Kidney Diseases
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• 제25권1호
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• pp.29-34
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• 2021

C3 glomerulonephritis (C3GN), a rare condition associated with dysregulation of the alternative pathway of the complement system, is histopathologically characterized by isolated or dominant C3 deposition in the renal glomeruli. We report a case of C3GN associated with anti-complement factor H (CFH) autoantibodies and CHF-related protein deficiency in an adolescent male. A 16-year-old adolescent male was admitted to a hospital with a 1-month history of generalized edema prior to presentation. Persistent microscopic hematuria and low serum C3 levels were incidentally detected at 7 and 10 years of age, respectively. Laboratory test results revealed hypoalbuminemia, nephrotic-range proteinuria, microscopic hematuria, and normal serum creatinine levels. The serum C3 and C4 levels were 17 mg/dL (normal 80-150 mg/dL) and 22 mg/mL (17-40 mg/mL), respectively. Renal biopsy showed typical features of C3GN. Further investigations revealed positive results on plasma anti-CFH autoantibody testing and a homozygous deletion of CFHR1 and CFHR3, which encode CFH-related proteins 1 and 3, respectively. Proteinuria persisted despite treatment with intravenous methylprednisolone, mycophenolate mofetil, and angiotensin-receptor blocker; however, his renal function remained stable. In conclusion, anti-CFH autoantibodies serve as important contributors to C3GN. This is the first case report that describes C3GN in an adolescent Korean male with anti-CFH autoantibodies and homozygous CFHR1 and CFHR3 deletion.

• 한국수산과학회지
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• 제56권3호
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• pp.309-314
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• 2023

Shark populations are constantly decreasing owing to environmental destruction and overfishing; thus, sharks are now at risk of extinction, with 30.5% of species classified as endangered on the International Union for Conservation of Nature's Red List. Sharks are apex predators and keystone species in balancing the marine food chain; their extinction would create an imbalance in the entire marine ecosystem. Assisted reproductive technology is a last resort for protecting animals facing extinction. Here, as a proactive effort toward building a hormone-induced artificial insemination protocol for endangered wild sharks, we identified the possibility of germ cell maturation by administration of GnRH, a commercially produced synthetic salmon gonadotropin-releasing hormone, and calculated its optimum dosage and injection timing. The experiment was conducted on one shark species, Chiloscyllium plagiosum. Injections were administered in 24 h intervals to C. plagiosum females, and 0.2 mL/kg+0.2 mL/kg were the optimal doses. These doses effectively induced maturation and, and ovulation, and oocyte release. Our results confirm that GnRH is a suitable tool for shark hormone-induced artificial insemination and indicate that this method may facilitate the conservation of endangered shark species.