• 한국진공학회:학술대회논문집
• /
• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
• /
• pp.233-233
• /
• 1999

본 연구에서는 2성분계 gas(Ne+Xe)를 사용하여 기체압력(p), 진동수(f)에 따라 VUV(Vacuum Ultra Violet) spectrum 147, 173nm 파장과 IR(Infrared) spectrum 823nm, 828nm을 Vacuum Monochromator(Acton-VM 507)를 통해 측정하였다. 휘도(Luminance)와 전력(Power)측면에서 Ne+ Xe 최적의 가스 조성비를 찾기 위해서 Xe의 혼합비에 따른 IR영역인 823nm, 828nm을 측정결과, Xe 4%일 때 좋은 효율을 나타냈다. 기체압력이 200Torr에서는 Xe(3P1)에 기인하는 147nm가 주요한 파장이며, 기체압력이 400Torr, 600Torr일때는 Xe(3P2)에 기인하는 173nm 파장이 주요함을 알 수 있었다. 또한 공간 방전 이미지를 전압 pulse 인가후 ICCD Camera(V-Tek)의 Ready time, On Time을 조절하면서 50ns delay로 관측하였다. 향후 실험계획은 실제 상용화되고 있는 혼합가스 He+Ne+Xe의 조성비에 따른 자세한 실험을 할 것이다.

• Nutrition Research and Practice
• /
• 제9권6호
• /
• pp.628-636
• /
• 2015

BACKGROUND/OBJECTIVES: Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS: Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS: Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS: These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice.

• 한국식품영양과학회지
• /
• 제31권1호
• /
• pp.87-91
• /
• 2002

톳 에탄올 추출물이 알코올을 투여한 흰쥐의 간조직 손상에 미치는 영향을 알아보기 위해 정상군, 알코올 투여군(35% ethanol, 10mL/kg B.W./day) 알코올 및 톳 에탄올 추출물 200mg/kg 및 400mg/kg 병합투여군의 4군으로 나누어 6간 사육 후 체중 증가율, 식이효율, 혈청중 ALT 및 ALP활성, 간조직의 손상억제효과를 검토하기 위해 SOD, catalase, XO 및 GSH-Px효소 활성을 측정하고 지질과산화물인 TBARS 와 GSH함량을 측정한 결과는 다음과 같다. 1) 체중증가율은 알코올 투여군이 정상군에 비하여 약 38%가 감소되었으나 알코올과 톳 에탄올 추출물(kg당 200mg 및 400mg)을 병합투여하여 알코올에 의해 둔화된 체중증가율이 정상군에 근접하도록 회복되었으며, 식이효율은 알코올 투여군이 정상군에 비하여 약 50%가 감소되었으나 톳 에탄올 추출물과 알코올의 병합투여로 증가되었다. 2) 간 손상지표 중의 하나인 혈청 ALT 및 ASP활성의 경우, 알코올 투여로 정상군에 비하여 160%정도 유의적으로 증가되었으나, 알코올과 톳 에탄올 추출물의 병합 투여로 알코올 투여군에 비하여 각각 63% 및 47%가 감소되었다. 3) 톳 에탄올 추출물은 알코올에 의해 증가된 세포질내의 XO활성을 감소시키지 못했으나 SOD, catalase 및 GSH-Px활성은 알코올 투여군에 비하여 각 56%, 38% 및 28%가 감소되었다. 4) 알코올만을 투여한 군의 TBARS함량은 정상군에 비하여 약 129%이상 증가되었으나, 알코올과 톳 에탄올 추출물 병합 투여로 알코올만을 투여한 군에 비하여 각각 34%, 56%의 감소를 나타냈는데 특히 400mg 투여가 더 많은 감소 효과를 보였다. 5) 알코올 투여로 간조직중의 GSH함량은 정상군에 비해 약 38%가 감소되었으나, 알코올과 톳 에탄올 추출물 병합 투여로 알코올 투여군에 비하여 각각 33% 및 66%가 증가되었다. 특히 400 mg 투여군의 경우 GSH함량 상승 효과가 우수하였다.

• 대한임상독성학회지
• /
• 제12권2호
• /
• pp.92-96
• /
• 2014

Dabigatran is the first oral direct thrombin inhibitor approved by the US Food and Drug Administration (FDA) for prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. Because dabigatran is excreted mainly by the kidneys, serum levels of dabigatran can be elevated to a supratherapeutic range in patients with renal failure, predisposing to emergent bleeding. We describe the case of a 66-year-old man taking dabigatran 150 mg twice daily for atrial fibrillation and cerebral infarction who presented with hematochezia and disseminated intravascular coagulation. Laboratory evaluation showed a hemoglobin level of 6.3 g/dL, platelets of $138,000/mm^3$, activated partial thromboplastin time (aPTT) of 10 s, and an international normalized ratio (INR) of 8.17. Colonoscopy showed a bleeding anal fissure. Hemostasis was provided by hemoclips and packed red blood cells and fresh frozen plasma were transfused. Since then, there was no further hematochezia, however, bleeding including oral mucosal bleeding, hematuria, and intravenous site bleeding persisted. At presentation, his serum creatinine was 4.96 mg/dL (baseline creatinine, 0.9 mg/dL). Dabigatran toxicity secondary to acute kidney injury was presumed. Because acute kidney injury of unknown cause was progressing after admission, he was treated with hemodialysis. Fresh frozen plasma transfusion was provided with hemodialysis. At 15 days from admission, there was no further bleeding, and laboratory values, including hemoglobin, partial thromboplastin time, and prothrombin time were normalized. He was discharged without bleeding. After 2 months, he undergoes dialysis three times per week and no recurrence of bleeding has been observed.

• Archives of Pharmacal Research
• /
• 제29권9호
• /
• pp.795-799
• /
• 2006

Peptides, although high efficacy and specificity in their physiological function, usually have low therapeutical activities due to their poor bioavailability when administrated orally. Nanoparticles have been regarded as a useful vector for targeted drug delivery system because they can protect drug from being degraded quickly and pass the gastrointestinal barriers. Here we described a novel oral N-trimethyl chitosan nanoparticles formulation containing thymopentin (Tp5-TMC-NP). N-trimethyl chitosan (TMC) was synthesized and then used to prepare Tp5-TMC-NP by ionotropic gelation. A three-factor, five-level CCD (Central Composite Design) design was used in the optimization procedure, with HPLC as the analyzing method. The resulting Tp5-TMC-NP had a regular spherical surface and a narrow particle size range with a mean diameter of 110.6 nm. The average entrapment efficiency was 78.8%. The lyophilized Tp5-TMC-NP formulation was stable in $4^{\circ}C\;or\;-20^{\circ}C$ after storage of 3 months without obvious changes in morphology, particle size, pH and entrapment ratio. The results of the flow cytometer determination showed that the ratio of $CD4^+/CD8^+$ of Wistar female rat given Tp5-TMC-NP (ig) was 2.59 time that of the group given Tp5 (ig).

• 한국염색가공학회지
• /
• 제5권4호
• /
• pp.79-91
• /
• 1993

The purpose of this study is to prepare the newer, more comfortable of urea-formaldehyde resin finished fabrics. The methods of this study are by making examinations and comparisons the relations between the thickness, fabrics counts, weight, moisture regain and crease recovery of cotton and viscose rayon fabrics caused by condition of urea-formaldehyde resin finishing and warm retaining ability and warm-cool sense. The analytic results of thermal character in state of fabrics material finished with urea-formaldehyde are as follows: 1. The warm retaining ability has no correlation with mixing ratio of resin but the increase of the warm retaining ability has correlation with the increase of concentration of urea-formaldehyde resin. 2. The result pf multiple regression analysis for effect of physical property according to the concentration of resin to the warm retaining ability revealed as below. As the weight, thickness and density increase and moisture regain decreases, the warm retaining ability increases. 3. The qmax value has no correlation with mixing ratio of resin but the increase of the qmax value has correlation with the increase of resin concentration. In the end, the effect of it promotes cool sense. 4. The result of multiple regression analysis for effect of physical property according to the concentration of resin to the qmax value revealed as below. As he weight and thickness increase, the qmax value decrease. But, as the density and crease recovery increase, the qmax value increase.

• 한국광학회:학술대회논문집
• /
• 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
• /
• pp.59-63
• /
• 1990

Two-stage TEA(transversely excited atmospheric pressure) CO2 laser amplifier system, Amp I and Amp II are consturcted and their amplification characteristics are investigated theoretically and experimentally. Multiple-wire corona preionization method is used for uniform discharge in laser oscillator and amplifiers. At optimumm gas ratio, CO2 : N2 : He = 1 : 1 : 3, output pulse energy of the oscillator is 0.4J and finally two-stage amplification gives 1.5J output energy which is larger than pumping threshold of para-H2 Raman laser. The rate equations of the amplifiers are solved numerically, and the results are compared with the experimental results. In conclusion, the small signal gain cocfficient of AMP I is 0.025/cm and that of AMP II is 0.02/cm.

• 한국광학회지
• /
• 제11권2호
• /
• pp.130-134
• /
• 2000

본 논문에서는 명암대비와 밝기를 높일 수 있는 반사형 쌍안정 TN셀의 광학 조건을 최적화 하였다. 세 파장(450 nm, 550nm, 650nm)의 광 특성에 미치는 영향을 살펴보았다. 그 결과 편광판 각도를 다른 광학 파라미터보다 더욱 정밀하게 제어해야 하며, dΔn 값이 밝은 상태의 색 특성에 영향을 미침을 알 수 있었다. 광대역 Ν4 필름을 사용해서 반사형 쌍안정 TN셀을 제작해 10.6:1이라는 명암대비를 얻었다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
• /
• pp.547-550
• /
• 2004

Indium tin oxide(ITO) films were prepared as a function of varying the proportion of oxygen$[0{\sim}1.0sccm]$ at fixed he gas[20sccm] by facing targets sputtering(FTS) system. Then electrical and optical properties of ITO thin films were estimated by Hall effect measurement system and UV/VIS-spectrometer. In the result, at very little oxygen rate, we can prepare a low resistivity ITO thin film of $3.40{\times}10^{-4}[\Omega{\cdot}cm]$ and transmittance of over 80%. So we noticed that the ITO thin film with low resistivity and high transmittance was prepared by FTS at room temperature.

• Nuclear Engineering and Technology
• /
• 제54권7호
• /
• pp.2614-2624
• /
• 2022

Monte Carlo simulations were used to model a portable Neutron backscattering (NBT) sensor suitable for detecting plastic anti-personnel mines (APMs) buried in dry and moist soils. The model consists of a 100 MBq ²⁵²Cf source encapsulated in a neutron reflector/shield assembly and centered between two ³He detectors. Multi-parameter optimization was performed to investigate the efficiency of Be/Zr(BH₄)₄ and Be/Be(BH₄)₂ assemblies in terms of increasing the signal-to-background (S/B) ratio and reducing the total dose equivalent rate. The MCNP results showed that 2 cm Be/3 cm Zr(BH₄)₄ and 2 cm Be/3 cm Be(BH₄)₂ are the optimal configurations. However, due to portability requirements and abundance of Be, the ²⁵²Cf-2 cm Be/3 cm Be(BH₄)₂ NBT model was selected to scan the center of APM buried 3 cm deep in dry and moist soils. The selected NBT model has positively identified the APM with a S/B ratio of 886 for dry soils of 1 wt% hydrogen content and with S/B ratios of 615, 398, 86, and 12 for the moist soils containing 4, 6, 10, and 14 wt% hydrogen, respectively. The total dose equivalent rate reached 0.0031 mSv/h, suggesting a work load of 8 h/day for 806 days within the permissible annual dose limit of 20 mSv.