• 제목/요약/키워드: Aggregation level

검색결과 221건 처리시간 0.023초

수용액(水溶液)에서 인삼배당체(人蔘配糖體)의 분자결합양상(分子結合樣相) (Pattern of Molecular Aggregation of Ginsenosides in Aqueous Solution)

  • 박훈;이미경;박귀희
    • Applied Biological Chemistry
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    • 제29권2호
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    • pp.198-206
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    • 1986
  • 정제인삼(精製人蔘)사포닌의 수용액을 분자투석막(分子透析膜)(분자량(分子量) 12000)을 통(通)하여 투석(透析)하거나 Bio-Gel P-2(분자량(分子量) $200{\sim}2000$)gel을 통과시켜 분취(分取)하고 HPLC로 ginsenoside를 분석(分析)하였다. Ginsenoside는 분자결합양상(分子結合樣相)과 분자내(分子內) 친수성기(親水性基)의 공간배열(空間配列)에 따라 3군(群)으로 분류(分類)되었다. 제(第) I 군(群)은 거대(巨大)미셀 형성자(形成者)로 결합분자수(結合分子數)가 10이상이며 I면친수기형(面親水基形)이고 panaxadiol인 $Ginsenoside\;Rb_1$, $Rb_2$, Rc 및 Rd가 포함된다. 제(第)II군(群)은 소(小)미셀형성자(形成者)로 결합분자수(結合分子數)가 10이상(以上)에서 1까지이고 불완전(不完全) 양면친수기형(兩面親水基形)이며 triol인 $Rg_2$와 Rf 및 diol인 $Rg_3$가 포함된다. 제(第)III군(群)은 단분자(單分子)로 존재(存在)하며 양면친수기형(兩面親水基形)이고 triol인 Re와 $Rg_1$을 포함한다.

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한계가치함수체계의 완전대체성과 상품결합성 (Perfect Substitution and Aggregation in A System of Marginal Valuation Functions)

  • 박환재
    • 자원ㆍ환경경제연구
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    • 제12권3호
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    • pp.427-452
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    • 2003
  • 본 연구는 모든 수요분석이 자료수집과 분석전에 완전대체성과 상품묶음을 사전적으로 가정하고 있으며, 일반적인 수요모형에서 수요함수 자체가 존재하지 않음을 주목하고 한계가치함수체계에서 완전대체성의 제약조건을 이론적으로 도출하였다. 그리고 완전대체성이 사전적인 제약으로 부과될 경우 수집된 자료와 일관되지 않음으로써 수요분석을 어렵게 할 경우 파레토의 계약곡선처럼 정보계약곡선을 이용하여 완전대체성의 정도를 조절할 수 있으며, 그 결과 도출되는 정보를 이용하여 상품묶음의 정도를 파악할 수 있음을 보여준다. 실증적 분석의 예로서 한국어류시장의 주요어종들간에 한계가치의 변화를 통하여 대체성의 정도를 파악하고 상품묶음을 할 수 있음도 보여준다. 비록 형태에 따른 어종이 다르더라도 소비자의 눈에서 보는 대체정도는 다른 것으로 볼 수 있으며, 그러한 시각에서 대체성과 상품묶음이 이루어질 수 있음도 보여준다. 이렇게 정보계약곡선을 따라 제약의 강도가 달라질 때 경제학적으로 합리적인 탄력성의 값을 택하여 후생분석으로 확장할 수 있음을 말해준다. 아직 이러한 연구가 초기단계이므로 많은 미래의 연구와 활용에 기여할 수 있을 것이다.

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DDoS 공격이 있는 MANET에서 패킷취합전송의 종단간 성능 (End-to-End Performance of Packet Aggregation Transmission on MANET under DDoS Attacks)

  • 김영동
    • 한국전자통신학회논문지
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    • 제9권6호
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    • pp.689-694
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    • 2014
  • MANET에서 DDoS 공격은 네트워크 기능을 수행해야하는 노드를 무력화시켜 네트워크 전체를 마비시키거나 노드의 위치에 따라 네트워크를 분리시키는 치명적인 결과를 초래할 수 있다. 짧은 길이의 데이터를 일정길이의 데이터로 모아서 전송하는 패킷취합전송은 MANET 환경에서 전송성능이 개선되는 효과를 보이고 있다. 본 논문에서는 이러한 MANET 환경에서 DDoS 공격이 패킷취합전송의 전송성능에 미치는 영향을 종단간 관점에서 측정하고 분석한다. 종단간 성능측정에는 NS-2를 기반으로 구축한 MANET 시뮬레이터를 이용하였으며, MOS, 연결율, 지연 및 패킷손실율을 측정 대상 성능 파라미터로 사용하였다. 음성서비스인 VoIP 트래픽을 측정대상 트래픽으로 사용했다. 본 논문의 결과로서 DDoS 공격이 있는 MANET에서 패킷취합수가 4이상일 때 전송품질 유지에 유리함을 확인하였다.

Comparative In Vitro Toxicity Study of Docetaxel and Nanoxel, a Docetaxel-Loaded Micellar Formulation Using Cultured and Blood Cells

  • Do, Van Quan;Park, Kwang-Hoon;Park, Jung-Min;Lee, Moo-Yeol
    • Toxicological Research
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    • 제35권2호
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    • pp.201-207
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    • 2019
  • Nanoxel-$PM^{TM}$ (Nanoxel) is a docetaxel-loaded methoxy-poly(ethylene glycol)-block-poly(D,L-lactide) (mPEG-PDLLA). This newly developed and marketed nanoformulation exhibits an improved pharmacokinetic profile, efficacy, and safety. Although the safety of Nanoxel to docetaxel as well as its bioequivalence must be clinically confirmed, all biological activities have not been examined in in vitro or in vivo studies. Here, the toxicity in a cultured cell system and the effects on blood cells were tested with Nanoxel and docetaxel. The in vitro cytotoxicity of Nanoxel was found to be comparable to or slightly lower than that of docetaxel depending on the concentrations tested or the cell types. Neither docetaxel nor Nanoxel induced erythrocytes hemolysis and produced reactive oxygen species up to $100{\mu}M$. However, Nanoxel was able to enhance the aggregatory response of platelets to collagen, whereas docetaxel attenuated such aggregation in a range of $50-100{\mu}M$, while thrombin-induced aggregation was not affected by either of them. Docetaxel or Nanoxel did not alter basal level of $Ca^{2+}$ and 5-hydroxytryptamine-evoked $Ca^{2+}$ transient in vascular smooth muscle cells. These results suggest that the mPEG-PDLLA micellar formulation alters the toxicological properties of docetaxel, and that extra cautions are needed when evaluating the safety of nanomedicine.

성소의 제거와 고콜레스테롤 식이 급여가 흰쥐의 혈장과 간의 콜레스테롤, 중성지방 수준과 혈소판 응집성 및 간 조직에 미치는 영향에 있어서 암.수의 차이 (Gender Difference in the Effects of Gonadectomy and Hypercholesterol Diet on Plasma and Liver Cholesterol and Triglyceride bevels, Platelet Aggregation and Liver Tissue in Sprague Dawley Rats)

  • 오인숙;강정애;강정숙
    • Journal of Nutrition and Health
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    • 제35권1호
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    • pp.15-23
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    • 2002
  • Gender differences in the effects of gonadectomy and high cholesterol diet on body weight and body cholesterol were investigated by using Sprague Dawley rats. Body weight, plasma and liver levels of cholesterol and triglyceride and platelet aggregation were examined in ovariectomized(OVX) or orchidectomized(ODX) rats with their intacts after feeding diet with or without 0.5% cholesterol. Body weight was significantly increased(p < 0.01) in OVX rats and significantly decreased(p < 0.01) in ODX rats compared to their respective intact rats, and cholesterol diet significantly(p < 0.05) decreased body weight in gonadectomized rats. Liver lobes from rats fed cholesterol diet were opaque and larger than those from rats find control dict, resulting in a significant increase(p < 0.01) in LW/BW ratio. Plasma and liver levels of total cholesterol were significantly increased (p < 0.01) in female rats regardless ovariectomy when find 0.5% cholesterol diet, but those levels in male rats were increased only when they were orchidectomized(p < 0.0l). Plasma HDL-cholesterol was significantly decreased(p < 0.05) in both sexes when find cholesterol diet. HDL-cholesterol were higher in female than male rats regardless treatments(p < 0.05). Liver triglyceride was significantly increased(p < 0.05) in both sexes when find cholesterol dict. Plasma level of triglyceride was not different among groups except significant decrease(p < 0.05) in cholesterol find ODX rats. Maximum platelet aggregation in female rats was significantly lower(p < 0.05) than male, but ovariectomy and cholesterol diet caused an increase te the level of male rats. Microscopic examination showed cholesterol diet caused a lipid accumulation in liver. Results indicate that intact female rats have higher response to hypercholestcrolemic diet than intact male rats and orchidectomy causes male rats more responsive to hypercholesterolemic diet. However, ovariectomy causes an increase female food efficiency ratio to the level of male rats, significantly increasing body weight.

동해안 심층수의 혈행 및 혈중지질 개선효과 (Effect of the Deep Sea Water of East Coast on Blood Flow and Serum Lipids)

  • 박미화;배송자;김미향
    • 한국해양바이오학회지
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    • 제1권2호
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    • pp.98-104
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    • 2006
  • 식생활의 서구화로 인하여 심혈관계질환의 발생빈도 증가로 인한 사망률이 늘어나고 있다. 따라서 최근 이용가치가 인정 되어지고 있는 해양 심층수를 이용하여 심혈관계 질환의 개선효과를 알아보았다. 심층수의 혈소판 응집 억제능을 알아보기 위해, in vitro 실험에서 washed platelet를 분리하여 심층수를 농도별로 처리한 후, collagen으로 혈소판 응집을 유도하여 심층수의 응집억제 실험을 한 결과 그 농도별로 응집이 감소되었다. 그리고 in vivo 실험에서도 심층수를 투여하지 않은 군에 비해 심층수를 투여한 군에서 혈소판 응집이 감소하였으므로 이는 심층수가 혈소판 응집에 효과적인 것으로 보여진다. 또한 혈청 중의 중성지질 함량이 감소되었고, 고밀도 지단백은 증가하였다. 혈류 속도 측정에서도 심층수를 투여한 그룹이 투여하지 않은 군에 비해 더 빠른 속도로 모세혈관을 빠져나가는 것을 볼 수 있었으며, 이것으로 보아 심층수를 투여한 그룹에서 혈행에 있어 좋은 효과가 있음을 나타내었다. 본 실험의 결과 심층수가 혈소판 응집, 혈청 지질 농도, 혈류 속도에 유효한 효과를 나타냄을 알 수 있었다. 이는 잘못된 식습관으로 오는 비만이나, 심혈관계질환에 유익한 결과를 줄 것으로 사료된다.

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감귤박, 다시마, 손바닥 선이장 분말을 함유한 식이의 급여가 고콜레스테롤혈증 흰쥐의 체내 지질수준과 장내 콜레스테롤 흡수, 혈소판 응집성 및 간 조직에 미치는 영향 (Hypocholesterolemic Effect of Tangerine Pulp, Sea Tangle or Prickly Pear Cactus on Lipid Level, Intestinal Cholesterol Absorption, Platelet Aggregation and Liver Tissue in Hypercholesterolemic Rats)

  • 강민숙;강정숙
    • Journal of Nutrition and Health
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    • 제34권2호
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    • pp.141-149
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    • 2001
  • This study done to investigate the hypocholesterolemic effect of ow dietary fiber in a high cholesterol diet in aspect of cholesterol absorption and excretion using Sprague Dawley rats. After feeding diets containing 0.5% cholesterol and 5% tangerine pulp, sea tangle or prickly pear cactus for four weeks, we measured the levels of plasma and liver cholesterol and triglyceride, fecal neutral sterols and fecal radioactivity after ingestion 14(sup)C-cholesterol. We also examined platelet aggregation and histological change in liver tissues in association of hypercholesterolemia. The liver to body weight ratio was significantly(p<0.01) lower in rats fed prickly pear cactus than in other groups. The levels of plasma total cholesterol, LDL-cholesterol and triglyceride were decreased significantly(p<0.01) in the prickly pear cactus group compared with the control, while there was no difference in the liver levels of total cholesterol and triglyceride among groups. Fecal corprostanol and cholesterol were significantly(p<0.01) higher groups of control and prickly pear cactus compared to the other two groups. Radioisotope excretion after ingestion of 14(sup)C-cholesterol was higher in the control group than in tangerine pulp group or sea tangle group, with the highest in prickly pear group. Radioisotope excretion was the highest during the 2nd and 3rd days in all groups. Hematocrit and platelet aggregation were decreased in all fiber groups compared to the control, but not statistically different. Microscopic examination showed that cholesterol diet cause a fat accumulation in the liver and prickly pear cactus decreased the fat accumulation. Result indicates that prickly pear cactus has hypocholesterolemic effect by decreasing absorption and increasing excretion of cholesterol, thereby protective effect on fatty liver. Control group fed diet containing high cholesterol and low fiber seems to have a self control system in cholesterol absorption and excretion preventing hypercholesterolemia. (Korean J Nutrition 34(2) : 141-149, 2001)

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Publish/Subscribe Protocol in Wireless Sensor Networks: Improved Reliability and Timeliness

  • Davis, Ernesto Garcia;Auge, Anna Calveras
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권4호
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    • pp.1527-1552
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    • 2018
  • The rapidly-evolving demand of applications using wireless sensor networks in several areas such as building and industrial automation or smart cities, among other, makes it necessary to determine and provide QoS support mechanisms which can satisfy the requirements of applications. In this paper we propose a mechanism that establishes different QoS levels, based on Publish/Subscribe model for wireless networks to meet application requirements, to provide reliable delivery of packet and timeliness. The first level delivers packets in a best effort way. The second one intends to provide reliable packet delivery with a novel approach for Retransmission Timeout (RTO) calculation, which adjusts the RTO depending on the subscriber Packet Delivery Ratio (PDR). The third one provides the same reliable packet delivery as the second one, but in addition, it provides data aggregation trying to be efficient in terms of energy consumption and the use of network bandwidth. The last one provides timeliness in the packet delivery. We evaluate each QoS Level with several performance metrics such as PDR, Message Delivery Ratio, Duplicated and Retransmitted Packet Ratio and Packet Timeliness Ratio to demonstrate that our proposal provides significant improvements based on the increase of the PDR obtained.

Clinical Study on the Effect of Exterior Vascular Laser Irradiation Therapy by Live Blood Analysis

  • Lee, Eun-Hyoung;Jeong, Jae-Ook;Min, Sung-Soon;Song, Su-Jin;Kim, Won-Ill
    • 대한한의학회지
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    • 제26권4호
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    • pp.143-151
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    • 2005
  • Objectives: The purpose of this study was to investigate the effect of exterior vascular laser irradiation therapy by live blood analysis. Methods: We analysed the changing forms of the live blood sample with a microscope before and after exterior vascular laser irradiation therapy of the blood. Results: Rouleau of red cells, erythrocyte aggregation of red cells, thrombocyte aggregation, uric acid crystals, red crystals, and protoplasts in blood were decreased significantly after exterior vascular laser irradiation therapy. Conclusions: This study suggests that exterior vascular laser irradiation will have positive effects in eliminating various effete matters in blood and will have efficacy in the treatment and prevention of cardiovascular system disorders and hyperlipidemia, caused by effete matters, or numbness and arthralgia caused by blood stagnancy and blood circulation disorder.

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Numerical Simulation of Blood Cell Motion in a Simple Shear Flow

  • Choi, Choeng-Ryul;Kim, Chang-Nyung;Hong, Tae-Hyub
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1487-1491
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    • 2008
  • Detailed knowledge on the motion of blood cells flowing in micro-channels under simple shear flow and the influence of blood flow is essential to provide a better understanding on the blood rheological properties and blood cell aggregation. The microscopic behavior of red blood cell (RBCs) is numerically investigated using a fluid-structure interaction (FSI) method based on the Arbitrary-Lagrangian-Eulerian (ALE) approach and the dynamic mesh method (smoothing and remeshing) in FLUENT (ANSYS Inc., USA). The employed FSI method could be applied to the motions and deformations of a single blood cell and multiple blood cells, and the primary thrombogenesis caused by platelet aggregation. It is expected that, combined with a sophisticated large-scale computational technique, the simulation method will be useful for understanding the overall properties of blood flow from blood cellular level (microscopic) to the resulting rheological properties of blood as a mass (macroscopic).

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