• 제목/요약/키워드: I-partition

검색결과 186건 처리시간 0.03초

FUZZY LOGIC KNOWLEDGE SYSTEMS AND ARTIFICIAL NEURAL NETWORKS IN MEDICINE AND BIOLOGY

  • Sanchez, Elie
    • 한국지능시스템학회논문지
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    • 제1권1호
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    • pp.9-25
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    • 1991
  • This tutorial paper has been written for biologists, physicians or beginners in fuzzy sets theory and applications. This field is introduced in the framework of medical diagnosis problems. The paper describes and illustrates with practical examples, a general methodology of special interest in the processing of borderline cases, that allows a graded assignment of diagnoses to patients. A pattern of medical knowledge consists of a tableau with linguistic entries or of fuzzy propositions. Relationships between symptoms and diagnoses are interpreted as labels of fuzzy sets. It is shown how possibility measures (soft matching) can be used and combined to derive diagnoses after measurements on collected data. The concepts and methods are illustrated in a biomedical application on inflammatory protein variations. In the case of poor diagnostic classifications, it is introduced appropriate ponderations, acting on the characterizations of proteins, in order to decrease their relative influence. As a consequence, when pattern matching is achieved, the final ranking of inflammatory syndromes assigned to a given patient might change to better fit the actual classification. Defuzzification of results (i.e. diagnostic groups assigned to patients) is performed as a non fuzzy sets partition issued from a "separating power", and not as the center of gravity method commonly employed in fuzzy control. It is then introduced a model of fuzzy connectionist expert system, in which an artificial neural network is designed to build the knowledge base of an expert system, from training examples (this model can also be used for specifications of rules in fuzzy logic control). Two types of weights are associated with the connections: primary linguistic weights, interpreted as labels of fuzzy sets, and secondary numerical weights. Cell activation is computed through MIN-MAX fuzzy equations of the weights. Learning consists in finding the (numerical) weights and the network topology. This feed forward network is described and illustrated in the same biomedical domain as in the first part.

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구절초 chrysanthemum sibiricum FISCHER의 성분 연구 (Studies on the consituents of Chrysanthemum sibiricum FISHER)

  • 이용주
    • 약학회지
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    • 제11권1_2호
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    • pp.7-16
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    • 1967
  • A yellowish microneedles, $C_{28}$ H$_{32}$ $O_{14}$ ${\cdot}$ I$_{1}$/$_2$, H$_{2}$O, m.p.262-$4^{\circ}$ , [${\alpha}$$_{D}^{20}$= -71,$43^{\circ}$(C = 0.42, pyridine), its acetate m.p.123-5.deg., were obtained in 0.3% yield from the leaves of Chrysanthemum sibiricum F$_{ISCHER}$. This substance is insoluble in water and the usual organic solvents except pyridine and ethylene glycol and, is not decomposed by dilute mineral acids but undergoes decomposition on being boiled in 60% H$_{2}$SO$_{4}$ or 35% HCl, giving one moel each of acacetin, glucose and rhamnose. It was not hydrolysed with a rhamnodiastase preparation obtained from the seeds of Rhamnus koraiensis. After permethylation of it, the uncrystallized product was hydrolysed and apigenin-5,4'-dimethyl ehter, m.p.$262^{\circ}$ was obtained, indicating that the disaccharide residue is at the 7 position of acacetin. Partial hydrolysis of this acacetin-7-rhamnoglucoside in cyclohexanol with formic acid gave acacetin-7-glucoside, m.p.246.deg. and rutinose, identifying them with authentic specimen on a paper chromatography. It was thus identified as linarin(acacetin-7-rutinoside) by means of mixed fusion, of paper partition chromatography and of its derivatives. Zemplen and Bognar suggested that the glucosidic linkage of linarin is .betha. by means of synthesis of this substance. But there is no evidence whether it is hydrolysed by emulsin or maltase or not. Linarin itself was not hydrolysed by an emulsin existing in the seed of Apricot or a maltase, but acacetin-7-glucoside(tilianin) which obtained from linarin gave acacetin and glucose on hydrolysis with the same emulsin and accordingly the glucosidic linkages of linarin and tilianin are thus regarded as ${\beta}$.

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Anti-tumor Constituents from Isodon xerophilus

  • Hou, Aijun;Lin, Zhongwen;Sun, Handong
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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    • pp.159-160
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    • 1998
  • Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

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Salient Object Detection via Multiple Random Walks

  • Zhai, Jiyou;Zhou, Jingbo;Ren, Yongfeng;Wang, Zhijian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권4호
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    • pp.1712-1731
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    • 2016
  • In this paper, we propose a novel saliency detection framework via multiple random walks (MRW) which simulate multiple agents on a graph simultaneously. In the MRW system, two agents, which represent the seeds of background and foreground, traverse the graph according to a transition matrix, and interact with each other to achieve a state of equilibrium. The proposed algorithm is divided into three steps. First, an initial segmentation is performed to partition an input image into homogeneous regions (i.e., superpixels) for saliency computation. Based on the regions of image, we construct a graph that the nodes correspond to the superpixels in the image, and the edges between neighboring nodes represent the similarities of the corresponding superpixels. Second, to generate the seeds of background, we first filter out one of the four boundaries that most unlikely belong to the background. The superpixels on each of the three remaining sides of the image will be labeled as the seeds of background. To generate the seeds of foreground, we utilize the center prior that foreground objects tend to appear near the image center. In last step, the seeds of foreground and background are treated as two different agents in multiple random walkers to complete the process of salient object detection. Experimental results on three benchmark databases demonstrate the proposed method performs well when it against the state-of-the-art methods in terms of accuracy and robustness.

Trellis 부호와 L번째 위상차 메트릭(metrics)을 갖는$\pi$/4 shift QPSK ($\pi$/4 shift QPSK with Trellis-Code and Lth Phase Different Metrics)

  • 김종일;강창언
    • 한국통신학회논문지
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    • 제17권10호
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    • pp.1147-1156
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    • 1992
  • 본 논문에서는 $\pi/4$ shift QPSK에 Trellis 부호화된 변조 기법(Trellis-Coded Modulation. TCM)을 적용시키기위하여 $\pi/8$ shift 8PSK를 제안하고 위상차에 의한 신호 집합 확장과 신호 집합 분할을 수행하는 trellis 부호화된 π/8 shift 8PSK를 제안한다. 또한 BER(Bit Error Rate) 성능을 향상시키기위하여 제1차 위상차뿐만아니라 제L차 이상차의 자승 유클리드 거리를 매트릭(Branch Metric)으로 갖는 비터비 디코더(Viterbi decoder)를 설계한다. 그리고 $\pi/4$ shift QPSK, trellis 부호화된 $\pi/8$ shift 8PSK와 제L차 위상차의 자승 유클리드 거리를 메트릭(Branch Metric)으로 갖는 trellis 부호화된 $\pi/8$ shift 8PSK 의 BER 특성을 AWGN에서 Monte Carlo 시뮬레이션을 통해 알아본다. 제안된 알고리즘은 MDPSK에도 적용될 수 있다.

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Biodistribution of 99mTc Tricarbonyl Glycine Oligomers

  • Jang, Beom-Su;Lee, Joo-Sang;Rho, Jong Kook;Park, Sang Hyun
    • Toxicological Research
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    • 제28권4호
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    • pp.235-240
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    • 2012
  • $^{99m}Tc$ tricarbonyl glycine monomers, trimers, and pentamers were synthesized and evaluated for their radiolabeling and in vivo distribution characteristics. We synthesized a $^{99m}Tc$-tricarbonyl precursor with a low oxidation state (I). $^{99m}Tc(CO)_3(H_2O)_3^+$ was then made to react with monomeric and oligomeric glycine for the development of bifunctional chelating sequences for biomolecules. Labeling yields of $^{99m}Tc$-tricarbonyl glycine monomers and oligomers were checked by high-performance liquid chromatography. The labeling yields of $^{99m}Tc$-tricarbonyl glycine and glycine oligomers were more than 95%. We evaluated the characteristics of $^{99m}Tc$-tricarbonyl glycine oligomers by carrying out a lipophilicity test and an imaging study. The octanol-water partition coefficient of $^{99m}Tc$ tricarbonyl glycine oligomers indicated hydrophilic properties. Single-photon emission computed tomography imaging of $^{99m}Tc$-tricarbonyl glycine oligomers showed rapid renal excretion through the kidneys with a low uptake in the liver, especially of $^{99m}Tc$ tricarbonyl triglycine. Furthermore, we verified that the addition of triglycine to prototype biomolecules (AGRGDS and RRPYIL) results in the improvement of radiolabeling yield. From these results, we conclude that triglycine has good characteristics for use as a bifunctional chelating sequence for a $^{99m}Tc$-tricarbonyl-based biomolecular imaging probe.

공간 효율적인 DNA 시퀀스 인덱싱 방안 (A Space Efficient Indexing Technique for DNA Sequences)

  • 송혜주;박영호;노웅기
    • 한국정보과학회논문지:데이타베이스
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    • 제36권6호
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    • pp.455-465
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    • 2009
  • 서픽스 트리는 공통의 프리픽스의 빈도수가 높을 때 효과적인 알고리즘으로, 한정된 문자로만 구성된 DNA 유사성 검색을 위한 연구에서 널리 활용되고 있다. 그러나, 서픽스 트리는 인덱스 특성상 메모리 공간을 많이 차지하며, 트리의 분할 시 DNA 시퀀스의 비율로 인한 쏠림현상이 발생한다는 문제점을 가진다. 따라서, 본 논문에서는 공통의 프리픽스를 가지는 가변길이의 파티셔닝 방법으로 합병하지 않는 인덱싱 방안인 SENoM을 제안한다. SENoM은 전체 시퀀스에서 공통의 프리픽스를 가지는 서픽스들의 발생 빈도수가 임계치 이하인 경우 디스크에 저장하고, 임계치 이상인 경우 임계치 이하가 될 때까지 프리픽스를 확장한다. 모든 파티션은 서브트리로 구축한 후 디스크에 저장하며, 질의처리를 위해, 구축된 파티션의 프리픽스를 서픽스로 가지는 트리를 구축한다. 제안하는 기법은 복잡한 합병과정을 제거하고, 많은 파티션 발생으로 인한 디스크 I/O 발생을 줄인다. 실험을 통해, SENoM이 Trellis 알고리즘에 비해 메모리 사용량을 약 35%, 인덱스 크기를 약 20% 감소시켰음을 보인다. 또한, 질의길이가 긴 경우에도 프리픽스 트리를 이용하여 효과적인 질의처리가 가능함을 보인다.

Effect of Vehicles and Enhancers on the in vitro Skin Penetration of Aspalatone and Its Enzymatic Degradation Across Rat Skins

  • Gwak, Hye-Sun;Chun, In-Koo
    • Archives of Pharmacal Research
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    • 제24권6호
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    • pp.572-577
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    • 2001
  • The feasibility of skin penetration was studied for aspalatone (AM, acetylsalicylic acid maltol ester), a novel antithrombotic agent. In this studys hairless mouse dorsal skins were used as a model to select composition of vehicle and AM. Based on measurements of solubility and partition coefficient, the concentration of PC that showed the highest flux for AM across the hairless mouse skin was found to be 40%. The cumulative amount permeated at 48 h, however, appear inadequate, even when the PC concentration was employed. To identify a suitable absorption enhancer and its optimal concentration for AM, a number of absorption enhancers and a variety of concentration were screened for the increase in transdermal flux of AM. Amongst these, linoleic acid (LOA) at the concentration of 5% was found to have the largest enhancement factor (i.e., 132). However, a further increase in AM flux was not found in the fatty acid concentration greater than 5%, indicating the enhancement effect is in a bell-shaped currie. In a study of the effect of AM concentration on the permeation, there was no difference in the permeation rate between 0.5 and 1% for AM, below its saturated concentration. At the donor concentration of 2%, over the saturated condition, the flux of AM was markedly increased. A considerable degradation of AM was found during permeation studies, and the extent was correlated with protein concentrations in the epidermal and serosal extracts, and skin homogenates. In rat dorsal skins, the protein concentration decreased in the rank order of skin homogenate > serosal extract > epidermal extract. Estimated first order degradation rate constants were $6.15{\pm}0.14,{\;}0.57{\pm}0.02{\;}and{\;}0.011{\pm}{\;}0.004{\;}h^{-1}$ for skin homogenate, serosal extract and epidermal extract, respectively. Therefore, it appeared that AM was hydrolyzed to some extent into salicylmaltol by esterases in the dermal and subcutaneous tissues of skin. taken together, our data indicated that transdermal delivery of AM is feasible when the combination of PC and LOA is used as a vehicle. However, since AM is not metabolically stable, acceptable degradation inhibitors may be nervessary to fully realize the transdermal delivery of the drug.

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5-아미노살리실산의 결장표적성 프로드럭 : 5-아미노살리실-L-글루타민산과 5-아미노살리실-L-아스파틸산의 합성 및 성상 (Synthesis and Properties of 5-Aminosalicyl-L-Aspartic Acid and 5-Aminosalicyl-L-glutamic Acid as Colon-Specific Prodrugs of 5-Aminosalicylic Acid)

  • 정연진;이정수;김학현;김영미;김대덕;한석규
    • 약학회지
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    • 제42권1호
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    • pp.5-11
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    • 1998
  • 5-Aminosalicyl-L-aspartic acid (5-ASA-Asp) and 5-aminosalicyl-L-glutamic acid (5-ASA-Glu) were synthesized as new colon-specific prodrugs of 5-aminosalicylic acid (5-ASA), their apparent partition coefficients, and the extent of conversion in the homogenates of tissue and contents of various G.I. Tract segments of rats were evaluated. These prodrugs were stable in the homogenate of tissue and contents of stomach, proximal small intestine (PSI) or distal small intestine (DSI). Release of 5-ASA from 5-ASA-Asp after incubation with the cecal and colonic contents for 8hrs at $37^{\circ}C$ was 18%, and 8%, respectively. No significant conversion of prodrug was observed in the cecal and colonic contents of rats pretreated with kanamycin sulfate, which indicated that microbial enzymes were responsible for the cleavage of these prodrugs.

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정신분열증 환자에서의 Haloperidol 및 Reduced Haloperidol의 혈장농도와 임상반응과의 상관성 (Relationship between Plasma Concentrations of Haloperidol and Its Metabolite, Reduced Haloperidol, and Clinical Response in Schizophrenia)

  • 박경호;김무진;이명걸;심창구;이민화
    • Journal of Pharmaceutical Investigation
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    • 제23권3호
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    • pp.165-177
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    • 1993
  • The relationship between the plasma haloperidol (HP) concentration and clinical response, and the effects of its active metabolite, reduced haloperidol (RH) on clinical response of HP were investigated in schizophrenic patients. In clinical study I, with 17 schizophrenic patients (male 8, fermale 9) who were administered with three different fixed doses of HP (15, 30 and 50 mg/day) for 3 weeks, the concentrations of HP and RH in plasma and blood and clinical response had been checked before and every week during the study. The clinical response was evaluated by the method of brief psychiatric rating scale (BPRS), and relative improvement of clinical response based on baseline BPRS (before drug treatment) was calculated. The concentrations of HP and RH in plasma and blood were assayed by HPLC. In clinical study II, the plasma RH/HP concentration ratios were checked in 11 patients who were administered with high doses of HP, over 60 mg a day, because of the poor clinical response at usual doses of HP. Plasma HP concentration and relative improvement of BPRS at 3 week in schizophrenic patients showed a 'curvilinear' relationship, and the clinical response was improved relatively over 50% based on the baseline BPRS in the range of $5{\sim}57\;ng/ml $ of HP in plasma. Also, the plasma RH concentrations were increased nonlinearly as the plasma HP concentration increased, and in high plasma HP concentration, over 30 ng/mI, clinical response gradually decreased, while the plasma RH/HP concentration ratio increased nonlinearly. Blood partition coefficients of HP and RH were not changed according to daily HP dose and duration of drug therapy. From these results, it is noted that the higher plasma RH/HP concentration ratio, resulted from the accumulation of RH as HP concentration increased, might explain the 'curvilinear' decrease of HP clinical response.

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