• Title/Summary/Keyword: Relative quantification

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Purine Derivatives Excreted in Urine as an Indicator Estimating Microbial Yield from the Rumen: A - Review

  • Kanjanapruthipong, J.;Len, R.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.3
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    • pp.209-216
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    • 1998
  • The paper presented here is aimed at increasing knowledge on purine metabolism in ruminants and hence the quantification of microbial cells entering the small intestine from urinaη excretion of purine derivatives. Nucleic acid metabolisms of micro-organisms in the rumen, digestion and absorption of nucleic acids entering the intestines, metabolisms of absorbed and endogenous purines involving de novo synthesis of nucleic acids in the ruminants host, and the relationship between absorbed and excreted purines are reviewed. Principal concerns about an amount of purine derivatives excreted in urine in relation to a change in purine-N: total-N ratios in rumen microbes that leave the rumen are discussed. The use of urinary excretion of purine derivatives as an indicator of the amount of microbial biomass leaving the rumen has to be done with some caution since it may be impossible to get a representative sample of microbes entering the intestine and thus yield estimates are relative rather than absolute.

Synthesis and Optically Characterization of CdSe Nanocrystal (CdSe 나노입자의 합성과 광학 특징)

  • Kim, Chanyoung;Kim, Sunghyun;Jung, Daehyuk
    • Journal of Integrative Natural Science
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    • v.1 no.3
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    • pp.250-253
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    • 2008
  • New issues arise as to surface characterization, quantification and interface formation. Surface and interface control of CdSe nanocrystal systems, one of the most studied and useful nanostructures. Semiconductor quantum dots (QDs) have been the subject of much interest for both fundamental reseach and technical applications in recent years, due mainly to their strong size dependent properties and excellent chemical processibility. In this dissertation, the synthesis of CdSe quantum dots were synthesized by pyrolysis of high-temperature organometallic reagents. In order to modify the size and quality of quantum dots, we controlled the growth temperature and the relative amount of precursors to be injected into the coordinating solvent. Moreover, an effective surface passivation of monodisperse nanocrystals was achieved by overcoating them with a higher-band-gap material. Synthesized CdSe quantum dots were studied to evaluate the optical, electronic and structural properties using UV-absorption, and photoluminescence measurement.

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A Study of Non-parametric Statistical Tests to Quantify the Change of Water Quality (수질변화의 계량화를 위한 비모수적 통계 준거에 관한 연구)

  • Lee, Sang-Hoon
    • Journal of Environmental Impact Assessment
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    • v.6 no.1
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    • pp.111-119
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    • 1997
  • This study was carried out to suggest the best statistical test which may be used to quantify the change of water quality between two groups. Traditional t-test may not be used in cases where the normality of underlying population distribution is not assured. Three non-parametric tests which are based on the relative order of the measurements, were studied to find out the applicability in water quality data analysis. The sign test is based on the sign of the deviation of the measurement from the median value, and the binomial distribution table is used. The signed rank test utilizes not only the sign but also the magnitude of the deviation. The Wilcoxon rank-sum test which is basically same as Mann-Whitney test, tests the mean difference between two independent samples which may have missing data. Among the three non-parametric tests studied, the singed rank test was found out to be applicable in the quantification of the change of water quality between two samples.

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Quantification of Positive and Negative Emotions by Single-Channel Brain Wave (단일 전극 뇌파에 의한 쾌,불쾌 감성의 정량화)

  • 최정미;황민철;배병훈;유은경;오상훈;김수용;김철중
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1997.11a
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    • pp.199-204
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    • 1997
  • 뇌전위에서 개인차가 없는 일반적인 규칙을 지닌 두 개의 정보 변수, 즉 ILF와 LHF 를 발견하였다. 이러한 일반성을 지닌 정보 변수가 청각, 후각, 촉각 자극에 의해 유발된 쾌하거나 불쾌한 감성 상태를 구분할 수 있으며 전두엽에서 그 경향이 두드러짐을 확인하였다. 전두엽의 뇌전위에서 감성 자극이 주어지기전과 자극이 주어지는 동안의 ILF, IHF값을 정규화함으로써 새로운 변수, Relative Quantified Emotional State(RQES)을 구현하였다. RQES는 쾌, 중립, 불쾌한감성의 정도를 선형적으로 정량화하였다. 따라서 하나의 전극으로 측정한 전두엽부분의 뇌전위로부터RQES 값을 계산하면 인간의 쾌, 불쾌 감성을 신뢰도있게 정량화 할 수 있다.

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Simultaneous Determination of Cinnamaldehyde and Coumarin in Oryeong-san using HPLC with Photodiode Array Detector

  • Seo, Chang-Seob;Shin, Hyeun-Kyoo
    • Herbal Formula Science
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    • v.18 no.2
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    • pp.251-257
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    • 2010
  • Objectives : To develop and validate High-performance liquid chromatography-photodiode array methods for simultaneous determination of two constituents in Oryeong-san(ORS). Methods : Reverse-phase chromatography using a Gemini C18 column operating at $40^{\circ}C$, and photodiode array(PDA) detection at 280 nm, were used for quantification of the two marker components of ORS. The mobile phase using a gradient flow consisted of two solvent systems. Solvent A was $H_2O$ and solvent B was acetonitrile. Results : Calibration curves were acquired with correlation coefficient ($r^2$)>0.9999, and the relative standard deviation(RSD) values(%) for intra- and inter-day precision were not exceed 1.0%. The recovery rate of each compound was in the range of 93.01-104.16%, with an RSD less than 2.0%. The contents of two compounds in ORS were 1.10-3.72 mg/g. Conclusions : The established HPLC method will be helpful to improve quality control of ORS.

Identification And Quantification of Steroidal Saponins in Polygonatum Species by HPLC/ESI/MS

  • Ahn, Mi-Jeong;Kim, Jin-Woong
    • Archives of Pharmacal Research
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    • v.28 no.5
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    • pp.592-597
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    • 2005
  • An HPLC/Esl/MS method has been developed to identify and quantify the spirostanol glycosides in the rhizomes of five Polygonatum species. The relative distribution of two steroidal saponins in each extract was established using the selective ion monitoring (SIM) mode via an electrospray ionization (ESI) source. It was found that there were significant differences in the amount of spirostanol glycosides among the Polygonatum Species. The results showed that this method could be used to identify the steroidal saponins in the extracts and differentiate Polygonatum species with high sensitivity and reproducibility in a short time. Fragmentation patterns of the two reference compounds were also discussed with the electrospray ionization multi-stage tandem mass spectroscopy (ESI-MS$^n$).

Computational evaluation of wind loads on buildings: a review

  • Dagnew, Agerneh K.;Bitsuamlak, Girma T.
    • Wind and Structures
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    • v.16 no.6
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    • pp.629-660
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    • 2013
  • This paper reviews the current state-of-the-art in the numerical evaluation of wind loads on buildings. Important aspects of numerical modeling including (i) turbulence modeling, (ii) inflow boundary conditions, (iii) ground surface roughness, (iv) near wall treatments, and (vi) quantification of wind loads using the techniques of computational fluid dynamics (CFD) are summarized. Relative advantages of Large Eddy Simulation (LES) over Reynolds Averaged Navier-Stokes (RANS) and hybrid RANS-LES over LES are discussed based on physical realism and ease of application for wind load evaluation. Overall LES based simulations seem suitable for wind load evaluation. A need for computational wind load validations in comparison with experimental or field data is emphasized. A comparative study among numerical and experimental wind load evaluation on buildings demonstrated generally good agreements on the mean values, but more work is imperative for accurate peak design wind load evaluations. Particularly more research is needed on transient inlet boundaries and near wall modeling related issues.

Damage assessment of shear-type structures under varying mass effects

  • Do, Ngoan T.;Mei, Qipei;Gul, Mustafa
    • Structural Monitoring and Maintenance
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    • v.6 no.3
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    • pp.237-254
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    • 2019
  • This paper presents an improved time series based damage detection approach with experimental verifications for detection, localization, and quantification of damage in shear-type structures under varying mass effects using output-only vibration data. The proposed method can be very effective for automated monitoring of buildings to develop proactive maintenance strategies. In this method, Auto-Regressive Moving Average models with eXogenous inputs (ARMAX) are built to represent the dynamic relationship of different sensor clusters. The damage features are extracted based on the relative difference of the ARMAX model coefficients to identify the existence, location and severity of damage of stiffness and mass separately. The results from a laboratory-scale shear type structure show that different damage scenarios are revealed successfully using the approach. At the end of this paper, the methodology limitations are also discussed, especially when simultaneous occurrence of mass and stiffness damage at multiple locations.

Quantifying Monetary Value of Float

  • Park, Young-Jun;Lee, Dong-Eun
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.111-113
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    • 2015
  • Floats are used by the parties involved in a construction project. The owner may use float by changing order(s) or by executing risk avoidance plan; the contractor may use it for leveling resources or substituting activities' construction methods to reduce costs. Floats are accepted either just as by-product obtained by critical path method(CPM) scheduling or as asset having significant value. Succinctly, existing studies involved in float value does not consider its' changes on project time domain. It is important to identify float ownership and to quantify its' corresponding values. This paper presents a method that quantifies float value of money that changes over project execution. The method which accurately computes the monetary value of float may contributes to resolve conflicts relative to float ownership and/or delay issues among project participants. It compares the difference between the monetary value of total float - on non-critical path in each and every schedule update. It makes use of critical path method (CPM) and commercial software with which practitioners are already familiar.

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Assessment of indoor air micro-flora in selected schools

  • Katiyar, Vinita
    • Advances in environmental research
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    • v.2 no.1
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    • pp.61-80
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    • 2013
  • Quantification of viable forms of microbial community (bacteria and fungi) using culture-dependent methods was done in order to characterize the indoor air quality (IAQ). Role of those factors, which may influence the concentration of viable counts of bacteria and fungi, like ventilation, occupancy, outdoor concentration and environmental parameters (temperature and relative humidity) were also determined. Volumetric-infiltration sampling technique was employed to collect air samples both inside and outside the schools. As regard of measurements of airborne viable culturable microflora of schools during one academic year, the level of TVMCs in school buildings was ranged between 803-5368 cfu/$m^3$. Viable counts of bacteria (VBCs) were constituted 63.7% of the mean total viable microbial counts where as viable counts of fungi (VFCs) formed 36.3% of the total. Mean a total viable microbial count (TVMCs) in three schools was 2491 cfu/$m^3$. Outdoor level of TVMCs was varied from 736-5855 cfu/$m^3$. Maximum and minimum VBCs were 3678-286 cfu/m3 respectively. Culturable fungal counts were ranged from 268-2089 cfu/$m^3$ in three schools. Significant positive correlation (p < 0.01) was indicated that indoor concentration of viable community reliant upon outdoor concentration. Temperature seemed to have a large effect (p < 0.05, p < 0.01) on the concentration of viable culturable microbial community rather than relative humidity. Consistent with the analysis and findings, the concentration of viable cultural counts of bacteria and fungi found indoors, were of several orders of magnitude, depending upon the potential of local, spatial and temporal factors, IO ratio appeared as a crucial indicator to identify the source of microbial contaminants.