• Journal of Astronomy and Space Sciences
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• 제21권2호
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• pp.83-92
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• 2004

질량비가 작은 접촉쌍성 GR Vir와 HV Aqr의 이미 발표된 분광 및 측광관측치를 WD프로그램에 적용하여 이 별들의 새로운 절대 물리량을 얻었다. GR Vir과 HV Aqr를 포함한 17개의 질량비가 작은 접촉쌍성들의 친화 상태를 조사하였다. 그 결과 질량비가 작은 접촉쌍성의 주성은 대부분 종년주계열상에 놓이며 반성은 영년주계열 아래 놓이고 있음을 확인하였다.

• Biomolecules & Therapeutics
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• 제3권3호
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• pp.229-232
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• 1995

In order to study if Glycyrrhizae Radix (GR) has protective effects on hepatotoxicity of acetaminophen in mouse, one of the species which are sensitive to acetaminophen-induced hepatotoxicity, effects of GR on liver weight to body weight ratio, serum alanine and aspartate transaminase (ALT and AST) activities, hepatic UDP-GT2 activity, and histopathologic changes were determined in acetaminophen-treated mice. Liver weight to body weight ratio and UDP-GT2 activity in mouse liver were not altered by GR. However, GR pretreatment lowered serum ALT and AST activities by 77% and 90% respectively, and diminished the degree of centrilobular necrosis caused by acetaminophen in liver as determined by histopathologic observation. These results suggest a possible protective effect of GR against the acetaminophen-induced hepatotoxicity in mice.

• 열처리공학회지
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• 제25권3호
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• pp.121-125
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• 2012

The large forgings used in chemical plants or nuclear power plants are produced by complex heat treatment. because of thickness up to 200~300 mm and weight up to 200~300 ton, setting proper heat treatment cycle is so difficult. In addition, defects of products make companies wasting large money and valuable time. In this study, to reduce try & err, when setting heat treatment of reactor pressure vessel steel SA508Gr.3, carrying out the basic mechanical property test of SA508 Gr.3 and testing hardness of SA508Gr.3 in various tempering temperature. and calculating temper curve with Hollomon-Jaffe parameter.

• Kyungpook Mathematical Journal
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• 제60권3호
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• pp.571-584
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• 2020

The object of the present paper is to characterize generalized Ricci recurrent (GR₄) spacetimes. Among others things, it is proved that a conformally flat GR₄ spacetime is a perfect fluid spacetime. We also prove that a GR₄ spacetime with a Codazzi type Ricci tensor is a generalized Robertson Walker spacetime with Einstein fiber. We further show that in a GR₄ spacetime with constant scalar curvature the energy momentum tensor is semisymmetric. Further, we obtain several corollaries. Finally, we cite some examples which are sufficient to demonstrate that the GR₄ spacetime is non-empty and a GR₄ spacetime is not a trivial case.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.43-46
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• 2007

Though bottom emission AM-OLED has advantages in respect of mass production, the bottom emission type is underrated due to its low aperture ratio and low color gamut, compared with top emission type. In this paper, we demonstrate that the color gamut up to 89 % can be simply achieved by depositing dielectric multilayers, whose thicknesses are determined using an optical simulation program, prior to formation of Si layer.

• Molecules and Cells
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• 제39권4호
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• pp.310-315
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• 2016

Coumarin is a phenolic compound that mainly affects the liver due to its metabolization into a toxic compound. The deterrent and ovicidal activities of coumarin in insect models such as Drosophila melanogaster have been reported. Here we explore the molecular mechanisms by which these insects protect themselves and their eggs from this toxic plant metabolite. Coumarin was fatal to the flies in a dosage-dependent manner. However, coumarin feeding could be inhibited through activation of the aversive gustatory receptor neurons (GRNs), but not the olfactory receptor neurons. Furthermore, three gustatory receptors, GR33a, GR66a, and GR93a, functioned together in coumarin detection by the proboscis. However, GR33a, but not GR66a and GR93a, was required to avoid coumarin during oviposition, with a choice of the same substrates provided as in binary food choice assay. Taken together, these findings suggest that anti-feeding activity and oviposition to avoid coumarin occur via separate mechanisms.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (3)
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• pp.76-78
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• 2002

Multicasting over mobile IP network becomes more important with the increasing needs of supporting multimedia services in mobile network. The IETF has suggested two approaches which are remote subscription and bidirectional tunneling for supporting mobility management in multicasting over mobile IP. But these protocols have problems - the frequent reconstruction of multicast delivery tree, packet less during handoff, convergence problem, and so on. In this paper, we propose to use preconfiguration of multicast delivery tree when mobile host enters the foreign network. It will decrease the frequency of multicast delivery tree reconstruction, and reduce the packet loss during handoff, Also the multicast delivery tree maintained by Keep Alive messages makes the signaling overload of networks diminished.

• 한국노년학
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• 제30권3호
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• pp.831-842
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• 2010

최근 한국사회의 고령화 및 노인장기요양 보험제도의 시작으로 노인 신체기능 및 장애에 대한 관심이 증가한 가운데, 이에 영향을 미치는 요인 중 하나로 근위축비만(Sarcopenic obesity) 즉, 근육양 감소와 지방량 증가가 동시에 나타나는 현상에 대한 관심이 증가하고 있다. 비만과 근 위축 각각이 노인의 신체기능에 미치는 영향에 대한 연구는 존재하나, 근위축 비만이 노인의 신체기능 및 체력에 미치는 영향에 관한 연구는 극히 제한적이다. 이에 본 연구는 경기도 Y시에 자립적으로 거주하는 60세 이상의 여성고령자 257명(평균연령 74.5세)의 신체조성을 측정한 후 Davison의 분류법을 이용하여 정상체지방군, 높은 체지방군, 근위축군, 근위축비만군의 4개 군으로 분류하고 7개의 노인신체기능측정(의자에서 앉았다 일어서기, 아령들기, 상완 유연성, 정적형성, 2분 제자리 걷기, 하지 유연성 및 8 feet 앉았다 일어서서 돌아오기(8ft TUG))검사항목과 측정장치를 이용한 4개의 기초체력항목(악력, 자세안정성, 무릎신근력 및 굴근력)에 미치는 영향을 조사하였다. SPSS 12.0을 이용하여 일원배치분산분석과 다중비교검정을 위한 LSD 사후검정을 실시하였으며 유의수준은 5%에서 검정하였다. 정상군의 의자에서 앉았다 일어서기, 아령들기, 상완유연성, 2분 제자리 걷기 결과는 근위축군(p<.05)과 근위축비만군(p<.05)보다 유의하게 높았다. 정적평형성은 정상군이 근위축비만군에 비하여 유의하게 높았으며(p<.01), 근위축군이 근위축비만군보다 유의하게 높았다(p<.01). 8ft TUG는 근위축비만군만이 정상군에 비하여 유의하게 낮은 결과를 보였다(p<.01). 악력(F=20.87,p<.001), 60도에서의 최대 신근력은 정상군이 근위축군(p<.01)과 근위축비만군(p<.01)보다 유의하게 높았으며 60도에서의 최대 굴극력역시 정상군이 근위축군(p<.01)과 근위축비만군(p<.01)보다 유의하게 높은 결과를 보였다. 본 연구의 결과는 노후의 자립적 삶을 영위하기 위한 기능유지의 위험인자로서 비만상태보다는 근위축비만군임을 입증하였으며, 노후 신체허약의 위험인자로 근위축비만에 대한 중재가 필요함을 보여주고 있다.

• 분석과학
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• 제24권4호
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• pp.249-255
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• 2011

물의 흡수에 의한 전분알갱이의 swelling은 물과 친화력이 있는 새로운 부분의 노출에 의하여 구조적인 변화로써 점진적으로, 때로는 갑작스럽게 변화를 일으킨다. 이러한 이유로 인해서, 물과의 접촉 시간에 따르는 전분 알갱이의 크기 또는 모양의 변화에 관심을 가진다. 중력 장-흐름 분획법(gravitation field-flow fractionation, GrFFF)은 마이크론 범위의 크기를 가지는 입자들을 분리하는 데에 유용한 분리기술이다. 본 연구에서는 감자와 고구마 전분알갱이들의 크기와 크기 분포도를 결정하는 데에 있어서 GrFFF의 응용가능성을 검사하고자 한다. GrFFF를 이용하여 물과의 접촉 시간에 따르는 전분 알갱이들의 크기분포도 변화를 모니터하였다. GrFFF로부터 얻어진 전분알갱이들의 크기 및 크기분포는 광학현미경(optical microscopy, OM) 결과와 비교하였다. 결과적으로 감자와 고구마 전분의 swelling은 물과의 접촉시간이 증가함에 따라 전분알갱이의 크기가 증가하며, 전분의 종류가 달라지면 swelling 속도가 달라짐을 확인하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제14권6호
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• pp.371-376
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• 2010

Glycyrrhizae radix (GR) is an herbal medicine that is commonly used in the East Asia for treating a variety of diseases, including stomach disorders. The objective of the present study was to examine the anti-stress effects of GR on repeated stress-induced alterations of anxiety, learning and memory in rats. Restraint stress was administered for 14 days (2 h/day) to the rats in the Control and GR groups (400 mg/kg/day, PO). Starting on the eighth day, the rats were tested for spatial memory on the Morris water maze test (MW) and for anxiety on the elevated plus maze (EPM). We studied the changes of the expressions of cholineacetyl transferase (ChAT) and tyrosine hydroxylase (TH) in the locus coerleus (LC) using immunohistochemistry. The results showed that the rats treated with GR had significantly reduced stress-induced deficits on their learning and memory on the spatial memory tasks. In addition, the ChAT immunoreactivities were increased. Gor the EPM, treatment with GR increased the time spent in the open arms (p<0.001) as compared to that of the control group. Moreover, GR treatment also normalized the increases of the TH expression in the LC (p<0.001). In conclusion, administration of GR improved spatial learning and memory and reduced stress-induced anxiety. Thus, the present results suggest that GR has the potential to attenuate the behavioral and neurochemical impairments caused by stress.