• Nutrition Research and Practice
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• 제9권6호
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• pp.606-612
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• 2015

BACKGROUND/OBJECTIVES: Several medicinal properties of Smilax china L. have been studied including antioxidant, anti-inflammatory, and anti-cancer effects. However, the antiobesity activity and mechanism by which the water-soluble fraction of this plant mediates its effects are not clear. In the present study, we investigated the lipolytic actions of the water-soluble fraction of Smilax china L. leaf ethanol extract (wsSCLE) in 3T3-L1 adipocytes. MATERIALS/METHODS: The wsSCLE was identified by measuring the total polyphenol and flavonoid content. The wsSCLE was evaluated for its effects on cell viability, lipid accumulation, glycerol, and cyclic adenosine monophosphate (cAMP) contents. In addition, western blot analysis was used to evaluate the effects on protein kinase A (PKA), PKA substrates (PKAs), and hormone-sensitive lipase (HSL). For the lipid accumulation assay, 3T3-L1 adipocytes were treated with different doses of wsSCLE for 9 days starting 2 days post-confluence. In other cell experiments, mature 3T3-L1 adipocytes were treated for 24 h with wsSCLE. RESULTS: Results showed that treatment with wsSCLE at 0.05, 0.1, and 0.25 mg/mL had no effect on cell morphology and viability. Without evidence of toxicity, wsSCLE treatment decreased lipid accumulation compared with the untreated adipocyte controls as shown by the lower absorbance of Oil Red O stain. The wsSCLE significantly induced glycerol release and cAMP production in mature 3T3-L1 cells. Furthermore, protein levels of phosphorylated PKA, PKAs, and HSL significantly increased following wsSCLE treatment. CONCLUSION: These results demonstrate that the potential antiobesity activity of wsSCLE is at least in part due to the stimulation of cAMP-PKA-HSL signaling. In addition, the wsSCLE-stimulated lipolysis induced by the signaling is mediated via activation of the ${\beta}$-adrenergic receptor.

• 융합정보논문지
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• 제9권12호
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• pp.47-53
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• 2019

본 연구의 목적은 VECM 모형(Vector Error Correction Model)을 활용해 해운 운임 간 인과관계를 분석하는 것이다. 분석에 사용된 해운 운임은 BDI(Baltic Dry Index), HRCI(Howe Robinson Containership Index), WS(World Scale rate), SCFI(Shanghai Containerized Freight Index)다. 분석 기간은 2013년 8월 2일부터 2019년 9월 6일까지이며 주간 데이터를 활용했다. VECM 모형 분석 결과, BDI는 일주일 전의 BDI에 많은 영향을 받는 것으로 분석되었으며, WS의 1% 상승은 일주일 후의 HRCI를 0.022% 상승시키는 것으로 분석되었다. HRCI 1% 상승은 일주일 후의 SCFI를 0.77% 상승시키며, WS는 일주일 전의 WS에 많은 영향을 받는 것으로 나타났다. 본 연구의 분석 결과는 각 해운시장의 해운 운임 예측에 도움을 주며, 이를 활용하여 의사결정자들이 올바른 의사결정을 할 수 있게 도움을 줄 수 있다고 사료된다.

• 대한한방내과학회지
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• 제26권1호
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• pp.48-59
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• 2005

Objectives : The aim of the study was to evaluate the effect of WS on HepG2 cell cycle and expression of related genes. Methods : The MTT assay, Cell counting analysis, $[^3H]-Thymidine$ Incorporation Assay, Flow cytometric analysis, Quantitative RT-PCR were studied. Results : WS inhibited HepG2 cell proliferation in low concentration$(1-10\;{\mu]g/ml)$ which did not cause direct cytotoxicity, with dose-dependant manner. WS in-hibited DNA synthesis as well. Flow cytometric analysis on the HepG2 cell showed G2/M phase arrest. Conclusion : These results suggest that WS inhibits HepG2 cell proliferation not by the gene regulation but by G2/M phase arrest in the cell cycle. Thus further studies on the effect of WS in G2/M phase regulation are thought to be needed.

• Tribology and Lubricants
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• 제25권1호
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• pp.61-65
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• 2009

Tribological properties of the semi-metallic friction materials containing different solid lubricants (graphite, $WS_2$, $MoS_2$) were investigated. The friction materials were fabricated with an experimental formulation and tested with gray cast iron disks. Results showed that graphite contributed to stabilize the friction coefficient during run-in processes. Also, graphite provided better fade resistance than that of $WS_2$ and $MoS_2$. At intermediate temperature ranges, however, friction materials with $WS_2$ or $MoS_2$ maintained higher friction effectiveness than that of graphite. On the other hand, friction materials containing $MoS_2$ showed increased wear rates than that with graphite or $WS_2$. Friction materials with proper combinations of two solid lubricants showed better friction and wear properties than that of the friction materials containing single solid lubricant.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.31-35
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• 2018

Tungsten disulfide($WS_2$) thin films were directly deposited by direct-current(DC) sputtering and annealed by rapid thermal processing(RTP) to materialize two-dimensional p-type transition metal dichalcogenide (TMDC) thin films on soda-lime glass substrates without any complicated exfoliation/transfer process. $WS_2$ thin films deposited at various DC sputtering powers from 80 W to 160W were annealed at different temperatures from $400^{\circ}C$ to $550^{\circ}C$ considering the melting temperature of soda-lime glass. The optical microscope results showed the stable surface morphologies of the $WS_2$ thin films without any defects. The X-ray photoelectron spectroscopy (XPS) results and the Hall measurement results showed stable binding energies of W and S and high carrier mobilities of $WS_2$ thin films.

• 임산에너지
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• 제17권1호
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• pp.8-22
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• 1998

남한강 유역의 소나무, 리기다소나무, 상수리나무, 굴참나무 및 신갈나무 군락을 대상으로 상대생장법에 의하여 현존량을 추정하였으며, 각 군락에 있어서 D2H와 줄기(Ws), 가지(Wb) 및 잎(Wl)의 상대생장식은 다음과 같다. 소나무 군락 : logWs=0.58482D2H-0.42417 logWb=0.6234D2H-1.2321 logWl=0.2247D2H-0.09359 리기다소나무 군락 : logWs=0.9218D2H-1.4692 logWb=1.0064D2H-2.2278 logWl=0.6275D2H-1.1715 상수리나무 군락 : logWs=0.96659D2H-1.56975 logWb=0.86315D2H-2.17944 logWl=0.79876D2H-1.97137 굴참나무 군락 : logWs=0.4753D2H＋0.20026 logWb=0.5725D2H-0.92006 logW1=0.61649D2H-1.4288 신갈나무 군락 : logWs=0.5526D2H-0.1228 logWb=0.5188D2H-0.9787 logWl=0.7754D2H-2.6273 상대생장식으로 추정한 현존량은 리기다소나무림 약 61만ton, 소나무림 약 120만ton, 상수리나무림 약 289ton, 굴참나무림 약 2,800ton 그리고 신갈나무림 약 57만ton으로서 소나무 군락이 전 지역의 약 43.9%를 점유하고 있다. 녹지자연도 등급별 현존량은 수령 20년 이상인 8등급에 속하는 삼림군락의 현존량 약 7만4천ton, 7등급에 속하는 삼림 약 200만ton으로서 7등급 군락이 전체의 75%를 차지하였으며, 식재림인 리기다소나무림은 약 61만 ton으로 측정되었다. 따라서 남한강 유역의 대표적인 자연림은 7등급에 속하는 소나무림과 신갈나무 군락이었다.

• Applied Microscopy
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• 제50권
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• pp.27.1-27.6
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• 2020

Transition metal dichalcogenides (TMD), which is composed of a transition metal atom and chalcogen ion atoms, usually form vacancies based on the knock-on threshold of each atom. In particular, when electron beam is irradiated on a monolayer TMD such as MoS₂ and WS₂, S vacancies are formed preferentially, and they are aligned linearly to constitute line defects. And then, a hole is formed at the point where the successively formed line defects collide, and metal clusters are also formed at the edge of the hole. This study reports a process in which the line defects formed in a monolayer WS₂ sheet expends into holes. Here, the process in which the W cluster, which always occurs at the edge of the formed hole, goes through a uniform intermediate phase is explained based on the line defects and the formation behavior of the hole. Further investigation confirms the atomic structure of the intermediate phase using annular dark field scanning transition electron microscopy (ADF-STEM) and image simulation.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.413-419
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• 1994

Mold growth decreased nutritive value of wheat straw (WS). Mold increased DM (94 vs 98%) and ADF (51 vs 56%) contents and had no effect on natural detergent fiber (NDF). Crude protein and N values were decreased in moldy wheat straw, Mold increased insoluble N content of wheat straw (WS) from 21 to 27%. Ammoniation increased the CP of nonmoldy straw from 3.8 to 8.3% and moldy straw from (3.3 to 6.2%). Aspergillus and zygomycetes fungal species were most prevalent and total numbers were higher on moldy straw. Ammoniation decreased total numbers of fungal spores on nonmoldy and moldy WS. Ammoniation of moldy WS increased (p < 0.10) feed in take (1.8%) as compared with nonmoldy, ammoniated, nonmoldy and moldy WS. Steers fed moldy WS had lowest (p < 0.10) feed intake (1.3% of BW daily) compared with other diet. There was little difference (p < 0.10) in intake of nonammoniated vs. ammoniated WS. Steers fed moldy straw lost 6 kg BW. Ammoniated, nonmoldy straw elevated Blood Urea Nitrogen (BUN) (10.5 mg/dl). Alkaline Phosphatase (ALK) was greater in steers fed moldy VS nonmoldy straw (148 VS 95 U/liter. p < 0.10).

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(1)
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• pp.611-616
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• 1997

The Level 1 probabilistic safety assessment(PSA) for Wolsong(WS) 2/3/4 nuclear power plant(NPPs) in design stage is performed using the methodologies being equivalent to PWR PSA. Accident sequence evaluation program(ASEP) human reliability analysis(HRA) procedure and technique for human error rate prediction(THERP) are used in HRA of WS 2/3/4 NPPs PSA. The purpose of this paper is to introduce the procedure and methodology of HRA in WS 2/3/4 NPPs PSA. Also, this paper describes the interim results of importance analysis for human actions modeled in WS 2/3/4 PSA and the findings and recommendations of administrative control of secondary control area from the view of human factors.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.324-325
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• 2012

다이아몬드 마이크로 블레이드의 절삭 효율을 향상시키고 소결 공정 중 윤활제의 유동성과 젖음성이 다이아몬드 마이크로 블레이드의 물성에 미치는 영향을 연구하기 위해 Cu/Sn 금속 결합재에 표면을 부식시킨 $WS_2$와 부식을 시키지 않은 $WS_2$ 윤활제를 각각 동일한 체적 분율로 첨가하였다. 윤활제의 표면 개질에 따른 마이크로 블레이드 결합재의 내마모성과 굽힘 강도 시험을 행하였고, 실착 절삭 시험을 위한 마이크로 블레이드 시편을 제작하여 수명 및 효율을 평가하였다. Cu/Sn 금속 결합재 파면에서의 $WS_2$ 입자 방향 분석을 통해 표면 개질 과정을 거친 $WS_2$가 압축소결 공정 중 압축 방향에 수직하게 위치하려는 경향이 크게 나타났으며, 이는 소결체의 강도와 경도를 향상시켰다. 마이크로 블레이드의 절삭 효율 및 수명을 평가하기 위한 실착 절삭 시험 결과, 윤활제 표면 부식처리는 처리하지 않은 경우에 비하여 절삭성능은 비슷하게 관찰되었으나 결합재와의 계면 결함을 줄이므로써 블레이드의 수명을 연장시킬 수 있었다.