• Title/Summary/Keyword: suspension of studies

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Phytochemical and pharmacological evaluation of the flowers of Sarcostemma brevistigma Wight

  • Lalitha, KG;Sethuraman, MG
    • Advances in Traditional Medicine
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    • v.9 no.3
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    • pp.252-258
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    • 2009
  • Shade-dried flowers of Sarcostemma brevistigma Wight Syn (SBF) belonging to Asclepiadaceae yielded a rare flavonol glycoside viz., Quercetin 5a prenyl, 3-O-glucosyl, 7-O-(4c-p-coumaroyl) neohesperidoside which were characterized based on chemical and spectral (including 2D NMR) studies. The ethyl acetate fraction of alcoholic concentrate (test sample) of flowers of this plant (SBF) was evaluated for its hepatoprotective and inhibition of lipid peroxidation activities to investigate the scientific basis of the traditional uses. The oral administration in varying doses viz., 125 and 250 mg/kg of aqueous suspension of SBF to rats for 7 days produced significant (P < 0.01) hepatoprotective effect comparable to that of standard drug silymarin. The SBF afforded good hepatoprotection against $CCl_4$ induced elevation levels of serum marker enzymes, serum bilirubin and liver weight. The free radical scavenging effects of SBF and flavonol glycoside (SA) were assigned by $Fe^{2+}$/ascorbate induction method (in vitro), which revealed the inhibition of lipid peroxidation. The SBF and SA showed prominent anti-lipid peroxidation activity ($IC_{50}$ about $\sim$180 mg/ml and 11.0 mg/ml respectively), which was comparable to standard drug curcumin ($IC_{50}$ about $\sim$8.25 mg/ml). Thus the hepatoprotective activity of SB could be correlated to the free radical scavenging property of the flavonol glycoside.

Structural damage alarming and localization of cable-supported bridges using multi-novelty indices: a feasibility study

  • Ni, Yi-Qing;Wang, Junfang;Chan, Tommy H.T.
    • Structural Engineering and Mechanics
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    • v.54 no.2
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    • pp.337-362
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    • 2015
  • This paper presents a feasibility study on structural damage alarming and localization of long-span cable-supported bridges using multi-novelty indices formulated by monitoring-derived modal parameters. The proposed method which requires neither structural model nor damage model is applicable to structures of arbitrary complexity. With the intention to enhance the tolerance to measurement noise/uncertainty and the sensitivity to structural damage, an improved novelty index is formulated in terms of auto-associative neural networks (ANNs) where the output vector is designated to differ from the input vector while the training of the ANNs needs only the measured modal properties of the intact structure under in-service conditions. After validating the enhanced capability of the improved novelty index for structural damage alarming over the commonly configured novelty index, the performance of the improved novelty index for damage occurrence detection of large-scale bridges is examined through numerical simulation studies of the suspension Tsing Ma Bridge (TMB) and the cable-stayed Ting Kau Bridge (TKB) incurred with different types of structural damage. Then the improved novelty index is extended to formulate multi-novelty indices in terms of the measured modal frequencies and incomplete modeshape components for damage region identification. The capability of the formulated multi-novelty indices for damage region identification is also examined through numerical simulations of the TMB and TKB.

Characteristics of Dough with Red Ginseng Marc Powder (홍삼박 분말을 첨가한 반죽의 특성)

  • Han, In-Jun;Kim, Mun-Yong;Chun, Soon-Sil
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.3
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    • pp.371-378
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    • 2007
  • Red ginseng has been considered a functional food, and many studies on red ginseng and the prevention of cancer, hypertension, arteriosclerosis and constipation have been conducted. In this study, white bread dough with 1, 2, 3, 4 or 5% red ginseng marc powder was measured by a farinograph, extensograph, amylograph, as well as for pH to evaluate the development time, stability, extensibility, resistance to extension, gelatinization temperature, and maximum viscosity temperature. The ash content of the wheat flour increased with an increasing content of red ginseng marc powder. The gelatinization maximum and the temperature for the gelatinization maximum of the flour-water suspension in the amylograph were not affected by the addition of red ginseng marc powder. The moisture absorption of the wheat flour in the farinograph increased as the content of red ginseng marc powder increased. Also, as the content of red ginseng marc powder increased, dough development time decreased. The extensibility of the dough in the extensograph showed a negative relationship with the amount of red ginseng marc powder added.

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Somatic Embryogenesis: Morphogenesis, Physiology, Biochemistry and Molecular Biology

  • Thorpe, Trevor A.
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.4
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    • pp.245-258
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    • 2000
  • Somatic embryogenesis has become a major tool in the study of plant embryology, as it is possible in culture to manipulate cells of many plant species to produce somatic embryos in a process that is remarkably similar to zygotic embryogenesis. Traditionally, the process has been studied by an examination of the ex vitro factors which influence embryo formation. Later structural, physiological and biochemical approaches have been applied. Host recently, molecular tools are being used. Together, these various approaches are giving valuable information on the process. This article gives an overview of somatic embryogenesis by reviewing information on the morphogenesis, physiology, biochemistry and molecular biology of the process. Topics covered include a brief description of the factors involved in the production of embryogenic cells. Carrot cell suspension is most commonly used, and the development of a high frequency and synchronous system is outlined. At the physiological and biochemical lev-els various topics, including the reactivation of the cell cycle, changes in endogenous growth regulators, amino acid, polyamine, DNA, RNA and protein metabolism, and embryogenic factors in conditioned medium are all discussed. Lastly, recent information on genes and molecular markers of the embryogenic process are outlined. Somatic embryogenesis, the best example of totipotency in plant cells, is not only an important tool in studies in basic biology, but is potentially of equal significance in the micropropagation of economically important plants.

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Studies on Production of Alkaloid by Plant Cell Culture of Corydalis remota (세포 현탁배양에 의한 현호색 알칼로이드의 생산)

  • Chang, Jung-In;Chi, Hyung-Joon;Shin, Seung-Won
    • Korean Journal of Pharmacognosy
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    • v.27 no.4
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    • pp.289-294
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    • 1996
  • In previous paper, we described the induced callus of Corydalis remota contains a significant amount of alkaloids. This study describes an optimal condition to maximize alkaloid production. The suspension cultures maintained alkaloid production ability after fifth subculture and a small amount of alkaloid seemed to be released out of cells. The yields of alkaloid by cultured cells was varied depending on the concentrations of NAA, carbon sources and phosphate ion and depending on the vitamin combinations and concentrations. Biosynthetic precursor and an elicitor treatment also affected the total alkaloid yield of the cultures. The optimal conditions for alkaloid production were as follows: 1) MS basal salt containing 30 g/l of glucose, 1.0 mg/l of NAA, and vitamins of LS medium should be used. 2) The culture should be treated with tyrosine 20 mg/l, and yeast extract 1.5 ml/l after the culture reached a stationary phase of growth. Five alkaloids were isolated from the cultures and they were characterized. The spectral data unambiguously revealed that the isolated compounds were dihydrosanguinarine, protopine. tetrahydropalmatine, allocyptopine and ambinine, respectively.

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Histopathologic Studies on the Brain and Lymphoid Organs in Hog Cholera III. Encephalitis of Pigs and Rabbits (Hog Cholera 병돈(病豚)의 뇌(腦) 및 임파장기(淋巴臟器)에 관한 병리조직학적(病理組織學的) 연구(硏究) III. 뇌염소견(腦炎所見)에 대하여)

  • Kwak, Soo-Dong;Lee, Cha-Soo
    • Korean Journal of Veterinary Research
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    • v.22 no.2
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    • pp.197-209
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    • 1982
  • This study was undertaken to clarify the histopathological changes of pigs naturally infected with hog cholera. Microscopic observations of the brain as well as clinical observations were carried out for the naturally and experimentally infected pigs with hog cholera viruses. Electron microscopically the vascular cuffings of the brain were also observed in the experiment. In addition, clinical and pathological studios were carried out in the rabbits inoculated with ALD, lapinized and isolated strain of hog cholera virus, respectively. The results obtained are as follows; Vascular cuffing of the brain was observed in about 97% of the natural cases and all of the experimental cases. Among the 496 cuffed blood vessels of natural cases, intramural cuffing (82.9%), intramural and perivascular cuffing (11.9%) and perivascular cuffing (5.2%) were seen, respectively. Electron microscopic findings on cuffed blood vessels of the brain were endothelial cellular degeneration, intramural separation and vacuolation, perivascular vacuolation and infiltration of pleomorphic lymphoid cells. In the rabbits dosed with tissue suspension of the lymphoid organs and isolated hog cholera virus, high body temperature and vascular cuffing of the brain were observed, meanwhile these changes were more significant in pre-injected cased with indian ink.

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Structural health monitoring of the Jiangyin Bridge: system upgrade and data analysis

  • Zhou, H.F.;Ni, Y.Q.;Ko, J.M.
    • Smart Structures and Systems
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    • v.11 no.6
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    • pp.637-662
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    • 2013
  • The Jiangyin Bridge is a suspension bridge with a main span of 1385 m over the Yangtze River in Jiangsu Province, China. Being the first bridge with a main span exceeding 1 km in Chinese mainland, it had been instrumented with a structural health monitoring (SHM) system when completed in 1999. After operation for several years, it was found with malfunction in sensors and data acquisition units, and insufficient sensors to provide necessary information for structural health evaluation. This study reports the SHM system upgrade project on the Jiangyin Bridge. Although implementations of SHM system have been reported worldwide, few studies are available on the upgrade of SHM system so far. Recognizing this, the upgrade of original SHM system for the bridge is first discussed in detail. Especially, lessons learned from the original SHM system are applied to the design of upgraded SHM system right away. Then, performance assessment of the bridge, including: (i) characterization of temperature profiles and effects; (ii) recognition of wind characteristics and effects; and (iii) identification of modal properties, is carried out by making use of the long-term monitoring data obtained from the upgraded SHM system. Emphasis is placed on the verification of design assumptions and prediction of bridge behavior or extreme responses. The results may provide the baseline for structural health evaluation.

Vertical vibrations of a bridge based on the traffic-pavement-bridge coupled system

  • Yin, Xinfeng;Liu, Yang;Kong, Bo
    • Earthquakes and Structures
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    • v.12 no.4
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    • pp.457-468
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    • 2017
  • When studying the vibration of a suspension bridge based on the traffic-bridge coupled system, most researchers ignored the contribution of the pavement response. For example, the pavement was simplified as a rigid base and the deformation of pavement was ignored. However, the action of deck pavement on the vibration of vehicles or bridges should not be neglected. This study is mainly focused on establishing a new methodology fully considering the effects of bridge deck pavement, probabilistic traffic flows, and varied road roughness conditions. The bridge deck pavement was modeled as a boundless Euler-Bernoulli beam supported on the Kelvin model; the typical traffic flows were simulated by the improved Cellular Automaton (CA) traffic flow model; and the traffic-pavement-bridge coupled equations were established by combining the equations of motion of the vehicles, pavement, and bridge using the displacement and interaction force relationship at the contact locations. The numerical studies show that the proposed method can more rationally simulate the effect of the pavement on the vibrations of bridge and vehicles.

Taxol Production in Taxus Cell Cultures: Effects of Various Elicitors (주목세포배양에 의한 Taxol 생산: 여러 가지 Elicitor가 미치는 영향)

  • 윤정환;김진훈
    • KSBB Journal
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    • v.10 no.2
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    • pp.143-148
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    • 1995
  • The effects of various elicitors, metabolic inhibitors and growth regulators on the production of diterpenoid anticancer agent taxol were investigated in cell suspension cultures of Taxus brevifolia. Cell cultures of T. brevifolia were treated by 5 kinds of biotic elicitors, 5 kinds of abiotic elicitors, 2 kinds of metabolic inhibitors and 8 kinds of growth regulators at the end of exponential growth phase. Among those treatments, chlorocholine chloride-an inhibitor of plant steroid metabolism-increased the taxol production most significantly. From a series of optimization studies, it was found that the addition of 1mM of chlorocholine chloride at the 9th day of culture was the best for taxol production. Taxol yield under this condition was 0.72mg/$\ell$.

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Linear regression analysis of buffeting response under skew wind

  • Guo, Zengwei;Ge, Yaojun;Zhao, Lin;Shao, Yahui
    • Wind and Structures
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    • v.16 no.3
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    • pp.279-300
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    • 2013
  • This paper presents a new analysis framework for predicting the internal buffeting forces in bridge components under skew wind. A linear regressive model between the internal buffeting force and deformation under normal wind is derived based on mathematical statistical theory. Applying this regression model under normal wind and the time history of buffeting displacement under skew wind with different yaw angles in wind tunnel tests, internal buffeting forces in bridge components can be obtained directly, without using the complex theory of buffeting analysis under skew wind. A self-anchored suspension bridge with a main span of 260 m and a steel arch bridge with a main span of 450 m are selected as case studies to illustrate the application of this linear regressive framework. The results show that the regressive model between internal buffeting force and displacement may be of high significance and can also be applied in the skew wind case with proper regressands, and the most unfavorable internal buffeting forces often occur under yaw wind.