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1

Quantitative analysis  

PubMed Central

Quantitative analysis permits the isolation of invariant relations in the study of behavior. The parameters of these relations can serve as higher-order dependent variables in more extensive analyses. These points are illustrated by reference to quantitative descriptions of performance maintained by concurrent schedules, multiple schedules, and signal-detection procedures. Such quantitative descriptions of empirical data may be derived from mathematical theories, which in turn can lead to novel empirical analyses so long as their terms refer to behavioral and environmental events. Thus, quantitative analysis is an integral aspect of the experimental analysis of behavior.

Nevin, John A.

1984-01-01

2

Increasing the Accuracy of MODIS Snow Product using Quantitative Restoration for MODIS Band 6 on Aqua  

NASA Astrophysics Data System (ADS)

A common problem in satellite imagery is striping and scan line dropout. While transmission errors are sometimes the cause of this problem, a more frequent source is damage to individual detectors, or to the electronics that record the response of the detectors. Launch, deployment into the harsh environment of space, particle bombardment, radiation, and space dust can result in detector damage at any point of an imager's life cycle. There are many examples of imagers which suffer from periodic line drop. Classical examples include Landsat 4 and 5. More recent examples include the 1.6 micron (Band 6) in MODIS on Aqua and WV 6.2 band on SEVIRI. To use standard image processing operations and off the shelf software, the missing data must be first estimated in some principled way. End users may have little or no knowledge of how to do that. It is important to note that many end users will often work with partial data, selected bands or regions of interest. The damaged bands create uncertainty in the reliability of the results of prediction algorithms that rely on that band. For example, the calculation of the NASA snow mask relies prominently on the Band 6 measurement in determining the likelihood of snow cover on the ground at the location of each pixel in the image. The current NASA-utilized solution to this problem is to use 2.1 micron (Band 7) measurements from MODIS on Aqua with an appropriately-adjusted algorithm. In response to the Band 6 problem, our group has developed an algorithm to recreate the missing Band 6 data from reliable data in the other 500m bands using quantitative restoration techniques. Our algorithm uses values in a spectral/spatial neighborhood of the pixel to be estimated, and proposes a value based on training data from the uncorrupted pixels. Due to the non-parametric nature of the estimator, we avoid the blurring inherent spatial interpolation, which has implicit smoothness priors. Our preliminary work shows this approach not only reduces the RMSE but restores the correct gradient information as well. We have shown that using all the neighboring channels we are able to quantitatively estimate the value at dead or noisy detectors applied to the MODIS band 6 case. We have performed an initial evaluation using MODIS Terra data, to estimate the potential benefit to the Aqua snow product. Since the corresponding band 6 of the MODIS/Terra has no such problem, it makes it possible to evaluate the algorithm by simulating the band 6 MODIS/Aqua damage on MODIS/Terra. Our tests demonstrate that NASA's snow product applied to our restored band 6, better matches the true band 6 snow product than the currently used band 7 proxy. We will present the evaluations based on several standard performance metrics that demonstrate that the use of the original NASA algorithm with the restored Band 6 data generates a more reliable snow mask than the modified algorithm with Band 7 data. In particular, the restored Band 6 data is much more reliable under certain conditions where the Band 7 algorithm tends to run into problems, including the very important border areas between snowy regions and snow-free regions, and areas where tree cover makes determinations of snow on the ground difficult.

Bonev, G.; Gladkova, I.; Grossberg, M.

2010-12-01

3

Towards energy decomposition analysis for open and closed shell f-elements mono aqua complexes  

NASA Astrophysics Data System (ADS)

We propose an energy decomposition analysis of mono aqua systems of both open and closed shell lanthanide and actinide cations using the CSOV scheme. We compared the values obtained with either large f-in-core or small core quasi relativistic pseudopotentials and computed the unpaired electrons contribution to the polarization energy component. Through a quasi-systematic approach on a number of chosen f-element cations, we quantified the different trends across both series for each contribution. This work is an important preliminary step for the acquisition of reference ab initio data for further parameterization of polarizable force fields for lanthanides and actinides.

Marjolin, A.; Gourlaouen, C.; Clavaguéra, C.; Dognon, J.-P.; Piquemal, J.-P.

2013-03-01

4

Quantitative analysis of software architectures  

Microsoft Academic Search

Quantitative analysis of software systems is a critical issue in the development of applications for heterogeneous distributed and mobile systems. It has been recognised that performance analysis should be integrated in the software development life cycle since the early stages. We focus on quantitative analysis of software architectures (SA) and in particular on performance models and languages to represent, evaluate

Simonetta Balsamo; Marco Bernardoand; Vincenzo Grassi

5

Quantitative analysis of system coupling  

Microsoft Academic Search

To solve the problem that it is difficult to calculate system coupling in the field of systems science and software engineering, this article discussed quantitative analysis of system coupling. It is difficult to calculate system coupling in the field of system science and software engineering. Consequently, this paper discussed quantitative analysis of system coupling to solve this problem. According to

Yin Zhang; Hua Zhou; Qing Duan; Yun Liao; Junhui Liu; Zhenli He

2011-01-01

6

Quantitative analysis of 'calanchi  

NASA Astrophysics Data System (ADS)

Three years (2006 - 2009) of monitoring data from two calanchi sites located in the western Sicilian Appennines are analyzed and discussed: the data comes from two networks of erosion pins and a rainfall gauge station. The aim of the present research is to quantitatively analyze the effects of erosion by water and to investigate their relationships with rainfall trends and specific properties of the two calanchi fronts. Each of the sites was equipped with a grid of randomly distributed erosion pins, made of 41 nodes for the "Catalfimo" site, and 13 nodes for the "Ottosalme" site (in light of the general homogeneity of its geomorphologic conditions); the erosion pins consist in 2 cm graded iron stakes, 100 cm long, with a section having a diameter of 1.6 cm. Repeated readings at the erosion pins allowed to estimate point topographic height variations; a total number of 21 surveys have been made remotely by acquiring high resolution photographs from a fixed view point. Since the two calanchi sites are very close each other (some hundred meters), a single rainfall gauge station was installed, assuming a strict climatic homogeneity of the investigated area. Rainfall data have been processed to derive the rain erosivity index signal, detecting a total number of 27 erosive events. Despite the close distance between the two sites, because of a different geologic setting, the calanchi fronts are characterized by the outcropping of different levels of the same formation (Terravecchia fm., Middle-Late Miocene); as a consequence, both mineralogical, textural and geotechnical (index) properties, as well as the topographic and geomorphologic characteristics, change. Therefore, in order to define the "framework" in which the two erosion pin grids have been installed, 40 samples of rock have been analyzed, and a geomorphologic detailed survey has been carried out; in particular, plasticity index, liquid limit, carbonate, pH, granulometric fractions and their mineralogic properties, electrical conductivity and sodium adsorption ratio (SAR), have been characterized. The analysis of the data allows to define relationships between the response of each erosion pin and the erosive rainfall events, the micro-hydrologic of its position and lithotechnical properties of the outcropping rocks. The estimations of the mean annual erosion rate and of the erosivity index, as well as results of the terrain analysis, largely agree with available data from literature observed in similar sites affected by calanchi development. Moreover, the gained results well reflect the differences of the morphologic features and their distribution on the two calanchi fronts; of particular interest is the spatial distribution and variability of piping landforms that markedly influence the development of gullies, specially on "Catalfimo" site, where a high frequency of pipes of different typologies can be detected.

Agnesi, Valerio; Cappadonia, Chiara; Conoscenti, Christian; Costanzo, Dario; Rotigliano, Edoardo

2010-05-01

7

The curium aqua ion.  

PubMed

The coordination environment of the hydrated Cm3+ ion is probed both in the solid state and in solution. The analysis of single-crystal X-ray diffraction data from [Cm(H2O)9](CF3SO3)3 determines that the Cm species is surrounded by nine coordinating waters with a tricapped-trigonal-prismatic geometry involving six short Cm-O distances at 2.453(1) A and three longer Cm-O distances at 2.545(1) A. The Cm nona-aqua triflate is isostructural with the series of lanthanide and actinide [R(H2O)9](CF3SO3)3 (R=La-Lu, Pu) compounds. A similar nona-aqua geometry is seen for the coordination environment of Cm in aqueous solution, as probed by high-energy X-ray scattering and extended X-ray absorption fine structure spectroscopy, although the splitting in the first coordination shell is increased from 0.092(2) in the solid to 0.16(2) A in solution. This increase in splitting of the Cm-water distances in the first coordination sphere is discussed in terms of its potential relevance to the previously observed decrease in coordinating waters with decreasing ionic radius about the f-ion in solution. PMID:17407283

Skanthakumar, S; Antonio, Mark R; Wilson, Richard E; Soderholm, L

2007-04-04

8

Analysis of tryptic digests indicates regions of GvpC that bind to gas vesicles of Anabaena flos-aquae.  

PubMed

The gas vesicles of the cyanobacterium Anabaena flos-aquae contain two main proteins: GvpA, which forms the ribs of the hollow cylindrical shell, and GvpC, which occurs on the outer surface. Analysis by MALDI-TOF MS shows that after incubating Anabaena gas vesicles in trypsin, GvpA was cleaved only at sites near the N-terminus, whereas GvpC was cleaved at most of its potential tryptic sites. Many of the resulting tryptic peptides from GvpC remained attached to the underlying GvpA shell: the pattern of attachment indicated that there are binding sites to GvpA at both ends of the 33-residue repeats (33RRs) in GvpC, although one of the tryptic peptides within the 33RR did not remain attached. Tryptic peptides near the two ends of the GvpC molecule were also lost. The mean critical collapse pressure of Anabaena gas vesicles decreased from 0.63 MPa to 0.20 MPa when GvpC was removed with urea or fully digested with trypsin; partial digestion resulted in partial decrease in critical pressure. PMID:16735729

Dunton, Peter G; Mawby, William J; Shaw, Virginia A; Walsby, Anthony E

2006-06-01

9

Quantitative analysis for ball lightning  

Microsoft Academic Search

Ball lightning is considered as a spherical standing wave of electromagnetic radiation trapped in a plasma shell. The shell is expelled out from an air-filled cavity by the ponderomotive force. The trapped radiation energy generates plasmas continuously through ohmic heating to prevent the shell from diffusing away. This consideration allows a quantitative analysis for the dimension, temperature, energy and life

Xue-Heng Zheng

1990-01-01

10

Validity in Quantitative Content Analysis  

ERIC Educational Resources Information Center

Over the past 15 years, educational technologists have been dabbling with a research technique known as quantitative content analysis (QCA). Although it is characterized as a systematic and objective procedure for describing communication, readers find insufficient evidence of either quality in published reports. In this paper, it is argued that…

Rourke, Liam; Anderson, Terry

2004-01-01

11

Analysis of an improved aqua-ammonia absorption refrigeration cycle employing evaporator blowdown to provide rectifier reflux  

Microsoft Academic Search

Increased concern over the continued availability of cheap oil and gas, combined with environmental concern relating to the large-scale combustion of fossil fuels has led to a renewal of interest in the absorption refrigeration cycle. The aqua-ammonia cycle is particularly suitable for applications in the process industries, where the refrigerant is required to be at temperatures below 0°C.A modification of

Stephen D. White; Brian K. O'Neill

1995-01-01

12

Aqua Education and Public Outreach  

NASA Astrophysics Data System (ADS)

NASA's Aqua satellite was launched on May 4, 2002, with six instruments designed to collect data about the Earth's atmosphere, biosphere, hydrosphere, and cryosphere. Since the late 1990s, the Aqua mission has involved considerable education and public outreach (EPO) activities, including printed products, formal education, an engineering competition, webcasts, and high-profile multimedia efforts. The printed products include Aqua and instrument brochures, an Aqua lithograph, Aqua trading cards, NASA Fact Sheets on Aqua, the water cycle, and weather forecasting, and an Aqua science writers' guide. On-going formal education efforts include the Students' Cloud Observations On-Line (S'COOL) Project, the MY NASA DATA Project, the Earth System Science Education Alliance, and, in partnership with university professors, undergraduate student research modules. Each of these projects incorporates Aqua data into its inquiry-based framework. Additionally, high school and undergraduate students have participated in summer internship programs. An earlier formal education activity was the Aqua Engineering Competition, which was a high school program sponsored by the NASA Goddard Space Flight Center, Morgan State University, and the Baltimore Museum of Industry. The competition began with the posting of a Round 1 Aqua-related engineering problem in December 2002 and concluded in April 2003 with a final round of competition among the five finalist teams. The Aqua EPO efforts have also included a wide range of multimedia products. Prior to launch, the Aqua team worked closely with the Special Projects Initiative (SPI) Office to produce a series of live webcasts on Aqua science and the Cool Science website aqua.nasa.gov/coolscience, which displays short video clips of Aqua scientists and engineers explaining the many aspects of the Aqua mission. These video clips, the Aqua website, and numerous presentations have benefited from dynamic visualizations showing the Aqua launch, instrument deployments, instrument sensing, and the Aqua orbit. More recently, in 2008 the Aqua team worked with the ViewSpace production team from the Space Telescope Science Institute to create an 18-minute ViewSpace feature showcasing the science and applications of the Aqua mission. Then in 2010 and 2011, Aqua and other NASA Earth-observing missions partnered with National CineMedia on the "Know Your Earth" (KYE) project. During January and July 2010 and 2011, KYE ran 2-minute segments highlighting questions that promoted global climate literacy on lobby LCD screens in movie theaters throughout the U.S. Among the ongoing Aqua EPO efforts is the incorporation of Aqua data sets onto the Dynamic Planet, a large digital video globe that projects a wide variety of spherical data sets. Aqua also has a highly successful collaboration with EarthSky communications on the production of an Aqua/EarthSky radio show and podcast series. To date, eleven productions have been completed and distributed via the EarthSky network. In addition, a series of eight video podcasts (i.e., vodcasts) are under production by NASA Goddard TV in conjunction with Aqua personnel, highlighting various aspects of the Aqua mission.

Graham, S. M.; Parkinson, C. L.; Chambers, L. H.; Ray, S. E.

2011-12-01

13

Quantitative basin analysis methods and applications  

Microsoft Academic Search

Quantitative basin analysis has become increasingly important in petroleum exploration. Chapter 1 presents a quantitative basin analysis study from the Georges Bank Basin, East Coast of the USA. By applying a one-dimensional fluid flow\\/compaction model to the well data of the basin, the author obtains a quantitative understanding of the basin's geohistory, geothermal history, and hydrocarbon generation history so that

Jianchang

1990-01-01

14

Quantitative analysis of sandstone porosity  

SciTech Connect

A quantitative analysis of changes in porosity associated with sandstone diagenesis was accomplished with digital back-scattered electron image analysis techniques. The volume percent (vol. %) of macroporosity, quartz, clay minerals, feldspar, and other constituents combined with stereological parameters, such as the size and shape of the analyzed features, permitted the determination of cement volumes, the ratio of primary to secondary porosity, and the relative abundance of detrital and authigenic clay minerals. The analyses were produced with a JEOL 733 Superprobe and a TRACOR/NORTHERN 5700 Image Analyzer System. The results provided a numerical evaluation of sedimentological facies controls and diagenetic effects on the permeabilities of potential reservoirs. In a typical application, subtle differences in the diagnetic development of porosity were detected in Wilcox sandstones from central Louisiana. Mechanical compaction of these shoreface sandstones has reduced the porosity to approximately 20%. In most samples with permeabilities greater than 10 md, the measured ratio of macroporosity to microporosity associated with pore-filling kaolinite was 3:1. In other sandstones with lower permeabilities, the measured ratio was higher, but the volume of pore-filling clay was essentially the same. An analysis of the frequency distribution of pore diameters and shapes revealed that the latter samples contained 2-3 vol% of grain-dissolution or moldic porosity. Fluid entry to these large pores was restricted and the clays produced from the grain dissolution products reduced the observed permeability. The image analysis technique provided valuable data for the distinction of productive and nonproductive intervals in this reservoir.

Ferrell, R.E. Jr.; Carpenter, P.K.

1988-01-01

15

BiDirectional optical communication with AquaOptical II  

Microsoft Academic Search

This paper describes AquaOptical II, a bidirectional, high data-rate, long-range, underwater optical communication system. The system uses the software radio principle. Each AquaOptical II modem can be programmed to transmit user defined waveforms and record the received waveforms for detailed analysis. This allows for the use of many different modulation schemes. We describe the hardware and software architecture we developed

Marek Doniec; Daniela Rus

2010-01-01

16

Reproducibility of quantitative coronary analysis  

Microsoft Academic Search

Because of limited storage capacity for digital images, angiographic laboratories without cinefilm are dependent on locally performed quantitative coronary angiography (QCA) in clinical studies. In the present study the intra-and interobserver variability, as well as variability between different laboratories and variability due to frame selection was analyzed. A total of 20 coronary lesions were studied in two different digital laboratories

Per A. Sirnes; Yngvar Myreng; Per Mølstad; Svein Golf

1996-01-01

17

Aqua Satellite Mission Educational Outreach  

NASA Astrophysics Data System (ADS)

An important component of the Aqua mission, launched into space on May 4, 2002 with a suite of six instruments from the U.S., Japan, and Brazil, is the effort to educate the public about the mission and the science topics that it addresses. This educational outreach includes printed products, web casts, other web-based materials, animations, presentations, and a student contest. The printed products include brochures for the mission as a whole and for the instruments, NASA Fact Sheets on the mission, the water cycle, and weather forecasting, an Aqua Science Writers' Guide, an Aqua lithograph, posters, and trading cards. Animations include animations of the launch, the orbit, instrument deployments, instrument sensing, and several of the data products. Each of these materials is available on the Aqua web site at http://aqua.nasa.gov, as are archived versions of the eight Aqua web casts. The web casts were done live on the internet and focused on the spacecraft, the science, the launch, and the validation efforts. All web casts had key Aqua personnel as live guests and had a web-based chat session allowing viewers to ask questions. Other web-based materials include a "Cool Science" section of the aqua.nasa.gov website, with videos of Aqua scientists and engineers speaking about Aqua and the science and engineering behind it, arranged in a framework organized for the convenience of teachers dealing with core curriculum requirements. The web casts and "Cool Science" site were produced by the Special Project Initiatives Office at NASA's Goddard Space Flight Center. Outreach presentations about Aqua have been given at schools, universities, and public forums at many locations around the world, especially in the U.S. A competition was held for high school students during the 2002-03 school year, culminating in April 2003, with five finalist teams competing for the top slots, followed by an awards ceremony. The competition had all the student teams analyzing an anomalous situation encountered by Aqua shortly after launch and the five finalist teams determining how best to handle a hypothetical degradation of the solid state recorder.

Parkinson, C. L.; Graham, S. M.

2003-12-01

18

Quantitative Analysis of Coronary Artery Inheritance.  

National Technical Information Service (NTIS)

The inheritance of coronary artery anatomical patterns in rats is polygenetically determined. In this study quantitative genetic analysis was used to determine the relative importance of genetic and environmental components involved in the genesis of coro...

A. S. Leon C. M. Bloor

1968-01-01

19

Quantitative Analysis of Bone Microstructure Using Tomosynthesis.  

National Technical Information Service (NTIS)

The purpose of the project is to determine the potential of Digital Tomosynthesis (DTS) for quantitative analysis of vertebral bone quality and for predicting vertebral bone fragility. The current scope, as a proof of concept study, is to compare paramete...

Y. N. Yeni

2012-01-01

20

Plural analysis: Multiple approaches to quantitative research  

Microsoft Academic Search

The dominant approach to decision analysis in particular, and quantitative research in general, issingular, i.e., all conclusions are based on a single preferred model or approach. Inplural analysis, several singular analyses are pursued in parallel, the typically conflicting results are merged. Although it is a central feature of intelligent everyday thinking, plural analysis has largely been ignored by the research

Rex V. Brown; Dennis V. Lindley

1986-01-01

21

Qualitative and Quantitative Analysis: Interpretation of Electropherograms  

NASA Astrophysics Data System (ADS)

In this chapter the basic information on qualitative and quantitative analysis in CE is provided. Migration time and spectral data are described as the most important parameters used for identification of compounds. The parameters that negatively influence qualitative analysis are briefly mentioned. In the quantitative analysis section the external standard and internal standard calibration methods are described. Variables influencing peak height and peak area in capillary electrophoresis are briefly summarized. Also, a discussion on electrodisperssion and its influence on a observed peak shape is provided.

Szumski, Micha?; Buszewski, Bogus?aw

22

Quantitative histogram analysis of images  

NASA Astrophysics Data System (ADS)

A routine for histogram analysis of images has been written in the object-oriented, graphical development environment LabVIEW. The program converts an RGB bitmap image into an intensity-linear greyscale image according to selectable conversion coefficients. This greyscale image is subsequently analysed by plots of the intensity histogram and probability distribution of brightness, and by calculation of various parameters, including average brightness, standard deviation, variance, minimal and maximal brightness, mode, skewness and kurtosis of the histogram and the median of the probability distribution. The program allows interactive selection of specific regions of interest (ROI) in the image and definition of lower and upper threshold levels (e.g., to permit the removal of a constant background signal). The results of the analysis of multiple images can be conveniently saved and exported for plotting in other programs, which allows fast analysis of relatively large sets of image data. The program file accompanies this manuscript together with a detailed description of two application examples: The analysis of fluorescence microscopy images, specifically of tau-immunofluorescence in primary cultures of rat cortical and hippocampal neurons, and the quantification of protein bands by Western-blot. The possibilities and limitations of this kind of analysis are discussed. Catalogue identifier: ADXG_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXG_v1_0 Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computers: Mobile Intel Pentium III, AMD Duron Installations: No installation necessary—Executable file together with necessary files for LabVIEW Run-time engine Operating systems or monitors under which the program has been tested: WindowsME/2000/XP Programming language used: LabVIEW 7.0 Memory required to execute with typical data:˜16MB for starting and ˜160MB used for loading of an image No. of bits in a word: 32 No. of processors used: 1 Has the code been vectorized or parallelized?: No No of lines in distributed program, including test data, etc.:138?946 No. of bytes in distributed program, including test data, etc.:15?166?675 Distribution format: tar.gz Nature of physical problem: Quantification of image data (e.g., for discrimination of molecular species in gels or fluorescent molecular probes in cell cultures) requires proprietary or complex software packages, which might not include the relevant statistical parameters or make the analysis of multiple images a tedious procedure for the general user. Method of solution: Tool for conversion of RGB bitmap image into luminance-linear image and extraction of luminance histogram, probability distribution, and statistical parameters (average brightness, standard deviation, variance, minimal and maximal brightness, mode, skewness and kurtosis of histogram and median of probability distribution) with possible selection of region of interest (ROI) and lower and upper threshold levels. Restrictions on the complexity of the problem: Does not incorporate application-specific functions (e.g., morphometric analysis) Typical running time: Seconds (depending on image size and processor speed) Unusual features of the program: None

Holub, Oliver; Ferreira, Sérgio T.

2006-11-01

23

Quantitative Chemical Analysis Online Materials  

NSDL National Science Digital Library

This is a site with materials related to a chemistry textbook. It is not as general as some sites but the material is of high pedagogical value. Short tutorial sections are available for many topics with extensive web linkages. "Living" graphs and Excel files illustrate important material such as pH fractional composition and statistical analysis. Students can take practice quizzes on material from the text. Full Powerpoint slideshows include nearly all of the figures contained in the text. A full set of laboratory experiments are available. Users must register to view much of the site's content; registration is free.

Harris, Daniel C., 1948-

2011-02-07

24

Quantitative WDS analysis using electron probe microanalyzer  

SciTech Connect

In this paper, the procedure for conducting quantitative elemental analysis by ZAF correction method using wavelength dispersive X-ray spectroscopy (WDS) in an electron probe microanalyzer (EPMA) is elaborated. Analysis of a thermal barrier coating (TBC) system formed on a Ni-based single crystal superalloy is presented as an example to illustrate the analysis of samples consisting of a large number of major and minor elements. The analysis was performed by known standards and measured peak-to-background intensity ratios. The procedure for using separate set of acquisition conditions for major and minor element analysis is explained and its importance is stressed.

Ul-Hamid, Anwar [Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia)]. E-mail: anwar@kfupm.edu.sa; Tawancy, Hani M. [Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia); Mohammed, Abdul-Rashid I. [Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia); Al-Jaroudi, Said S. [Saudi Aramco, P.O. Box 65, Tanajib 31311 (Saudi Arabia); Abbas, Nureddin M. [Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia)

2006-04-15

25

Quantitative Analysis by Derivative Electronic Spectroscopy  

Microsoft Academic Search

Absorption and emission spectroscopy in the ultraviolet and visible regions, apart from being the earliest physical techniques of analysis, have great utility in solving a variety of structural and analytical problems [l-41. However, in many cases the quantitative determination of individual components in a mixture by UV-VIS spectroscopy becomes very difficult owing to the spectral similarities and overlapping of weak

L. Dixit; S. Ram

1985-01-01

26

Quantitative Analysis by Auger Electron Spectroscopy  

Microsoft Academic Search

A short review is presented of the theoretical background of a physical model for the quantification of Auger electron spectroscopy (AES) for surface analysis. The recent studies on the data-base for the inelastic mean free paths (IMFP) by Seah and Dench and systematic calculations of the backscattering factors (R) by Shimizu and Ichimura have now enabled standard quantitative corrections comparable

Ryuichi Shimizu

1983-01-01

27

Quantitative methods for ecological network analysi  

Microsoft Academic Search

The analysis of networks of ecological trophic transfers is a useful complement to simulation modeling in the quest for understanding whole-ecosystem dynamics. Trophic networks can be studied in quantitative and systematic fashion at several levels. Indirect relationships between any two individual taxa in an ecosystem, which often differ in either nature or magnitude from their direct influences, can be assayed

Robert E. Ulanowicz

2004-01-01

28

Seniors' Online Communities: A Quantitative Content Analysis  

ERIC Educational Resources Information Center

|Purpose: To examine the contents and characteristics of seniors' online communities and to explore their potential benefits to older adults. Design and Methods: Quantitative content analysis of a full year's data from 14 leading online communities using a novel computerized system. The overall database included 686,283 messages. Results: There…

Nimrod, Galit

2010-01-01

29

On the Limitations of Quantitative Analysis.  

National Technical Information Service (NTIS)

The notion that numbers and logic ought to rule the universe has been around since Pythagorus. Yet, until recently, few have had much faith that this might actually come to pass. Quantitative analysis admittedly had a place in engineering and science, and...

E. S. Quade

1970-01-01

30

Quantitative analysis of collaborative and mobility networks  

Microsoft Academic Search

This study proposes a quantitative analysis of researcher mobility (i.e. transfer from one institution to another) and collaborative\\u000a networks on the basis of author background data extracted from biographical notes in scientific articles to identify connections\\u000a that are not revealed via simple co-authorship analysis. Using a top-ranked journal in the field of computer vision, we create\\u000a a layered network that

Takao Furukawa; Nobuyuki Shirakawa; Kumi Okuwada

2011-01-01

31

Comprehensive quantitative analysis on privacy leak behavior.  

PubMed

Privacy information is prone to be leaked by illegal software providers with various motivations. Privacy leak behavior has thus become an important research issue of cyber security. However, existing approaches can only qualitatively analyze privacy leak behavior of software applications. No quantitative approach, to the best of our knowledge, has been developed in the open literature. To fill this gap, in this paper we propose for the first time four quantitative metrics, namely, possibility, severity, crypticity, and manipulability, for privacy leak behavior analysis based on Privacy Petri Net (PPN). In order to compare the privacy leak behavior among different software, we further propose a comprehensive metric, namely, overall leak degree, based on these four metrics. Finally, we validate the effectiveness of the proposed approach using real-world software applications. The experimental results demonstrate that our approach can quantitatively analyze the privacy leak behaviors of various software types and reveal their characteristics from different aspects. PMID:24066046

Fan, Lejun; Wang, Yuanzhuo; Jin, Xiaolong; Li, Jingyuan; Cheng, Xueqi; Jin, Shuyuan

2013-09-16

32

Comprehensive Quantitative Analysis on Privacy Leak Behavior  

PubMed Central

Privacy information is prone to be leaked by illegal software providers with various motivations. Privacy leak behavior has thus become an important research issue of cyber security. However, existing approaches can only qualitatively analyze privacy leak behavior of software applications. No quantitative approach, to the best of our knowledge, has been developed in the open literature. To fill this gap, in this paper we propose for the first time four quantitative metrics, namely, possibility, severity, crypticity, and manipulability, for privacy leak behavior analysis based on Privacy Petri Net (PPN). In order to compare the privacy leak behavior among different software, we further propose a comprehensive metric, namely, overall leak degree, based on these four metrics. Finally, we validate the effectiveness of the proposed approach using real-world software applications. The experimental results demonstrate that our approach can quantitatively analyze the privacy leak behaviors of various software types and reveal their characteristics from different aspects.

Fan, Lejun; Wang, Yuanzhuo; Jin, Xiaolong; Li, Jingyuan; Cheng, Xueqi; Jin, Shuyuan

2013-01-01

33

Aqua MODIS: Science and Beauty  

NASA Video Gallery

Beautiful images from the MODIS instrument on NASA's Aqua and Terra satellites are used by people all over the world every day. But MODIS is about more than just pretty pictures -- the instrument's contributions to science include a better understanding of the Earth's cloud cover, aerosols, phytoplankton levels, and land cover. > Download high-res video

gsfcvideo

2012-05-14

34

Aqua 10 Years After Launch.  

National Technical Information Service (NTIS)

A little over ten years ago, in the early morning hours of May 4, 2002, crowds of spectators stood anxiously watching as the Delta II rocket carrying NASA's Aqua spacecraft lifted off from its launch pad at Vandenberg Air Force Base in California at 2:55 ...

C. L. Parkinson

2013-01-01

35

Journal of Financial and Quantitative Analysis (JFQA)  

NSDL National Science Digital Library

The Journal of Financial and Quantitative Analysis is published by the School of Business Administration at the University of Washington, Seattle. It publishes theoretical and empirical research in financial economics. The web site details the instructions on submitting articles for publications; table of contents and abstracts of previous articles are also accessible. Full text of articles that have been accepted for publication are available in Acrobat format.

2005-11-30

36

Quantitative fluorescence spectral analysis of protein denaturation.  

PubMed

This chapter describes a procedure of global analysis of the steady-state spectra measured with different concentrations of the denaturant to quantitatively study protein denaturation. With the help of physicochemical models, relevant spectral parameters that characterize the folding intermediate and thermodynamic parameters that describe a three-state model N?[Formula: see text]?I?[Formula: see text]?U can be estimated. PMID:24108622

van Stokkum, Ivo H M; Laptenok, Sergey P

2014-01-01

37

Capture and Analysis of Quantitative Proteomic Data  

PubMed Central

Whilst the array of techniques available for quantitative proteomics continues to grow, the attendant bioinformatic software tools are similarly expanding in number. The data capture and analysis of such quantitative data is obviously crucial to the experiment and the methods used to process it will critically affect the quality of the data obtained. These tools must deal with a variety of issues, including identification of labelled and unlabelled peptide species, location of the corresponding mass spectrometry scans in the experiment, construction of representative ion chromatograms, location of the true peptide ion chromatogram start and end, elimination of background signal in the mass spectrum and chromatogram, and calculation of both peptide and protein ratios/abundances. A variety of tools and approaches are available, in part restricted by the nature of the experiment to be performed and available instrumentation. Currently, although there is no single consensus on precisely how to calculate protein and peptide abundances, many common themes have emerged which identify and reduce many of the key sources of error. These issues will be discussed, along with those relating to deposition of quantitative data. At present, mature data standards for quantitative proteomics are not yet available, although formats are beginning to emerge.

Lau, King Wai; Jones, Andrew R; Swainston, Neil; Siepen, Jennifer A; Hubbard, Simon J

2008-01-01

38

Quantitative HRTEM analysis of FIB prepared specimens.  

PubMed

The preparation of good transmission electron microscopy specimens with minimum milling damage can be very complicated, especially from a specific area in a sample. Therefore, a novel approach for transmission electron microscopy specimen preparation using a focused ion beam system is proposed, based on the use of low energy (5 kV)Ga ions and a low incident ion angle (approximately 1 degree ) from a thickness of approximately 500 nm until the sample is electron transparent. Transmission electron microscopy specimens prepared by this method have significantly less irradiation damage, demonstrated by successful quantitative high-resolution transmission electron microscopy conducted on sapphire from data acquired using an aberration-corrected field emission gun transmission electron microscopy. Quantitative analysis was conducted by iterative digital image matching. The accuracy and sensitivity of the matching process is discussed. PMID:19094016

Baram, M; Kaplan, W D

2008-12-01

39

Quantitative analysis of non-Hodgkin's lymphoma.  

PubMed Central

A preliminary attempt has been made to characterise a small series of non-Hodgkin's lymphomas (NHL) by morphometric means using the Quantimet 720 Kontron MOP/AMO3 image analysis systems. In most cases it was found that the distribution of nuclear area and correlation between mean nuclear area and frequency per unit field, corresponded closely with tumour classification determined by light microscopy. These results suggest that it may be possible to devise an objective and reproducible grading system for NHL using quantitative morphometric techniques.

Abbott, C R; Blewitt, R W; Bird, C C

1982-01-01

40

Quantitative proteomic analysis of intact plastids.  

PubMed

Plastids are specialized cell organelles in plant cells that are differentiated into various forms including chloroplasts, chromoplasts, and amyloplasts, and fulfill important functions in maintaining the overall cell metabolism and sensing environmental factors such as sunlight. It is therefore important to grasp the mechanisms of differentiation and functional changes of plastids in order to enhance the understanding of vegetality. In this chapter, details of a method for the extraction of intact plastids that makes analysis possible while maintaining the plastid functions are provided; in addition, a quantitative shotgun method for analyzing the composition and changes in the content of proteins in plastids as a result of environmental impacts is described. PMID:24136541

Shiraya, Takeshi; Kaneko, Kentaro; Mitsui, Toshiaki

2014-01-01

41

EGFR Protein Expression in Non-Small Cell Lung Cancer Predicts Response to an EGFR Tyrosine Kinase Inhibitor - A Novel Antibody for Immunohistochemistry or AQUA Technology  

PubMed Central

Introduction Epidermal growth factor receptor (EGFR) protein expression in non-small cell lung cancer (NSCLC) is not recommended for predicting response to EGFR tyrosine kinase inhibitors (TKIs) due to conflicting results, all using antibodies detecting EGFR external domain (ED). We tested the predictive value of EGFR protein expression for response to an EGFR TKI using an antibody that detects the intracellular domain (ID) and compared fluorescence-based Automated QUantitative Analysis (AQUA) technology to immunohistochemistry (IHC). Methods Specimens from 98 gefitinib-treated NSCLC Japanese patients were evaluated by IHC (n=98/98) and AQUA technology (n=70/98). EGFR ID- (5B7) and ED-specific antibodies (3C6 and 31G7) were compared. Results EGFR expression evaluated with 5B7 was significantly higher in responders versus non-responders to gefitinib both with IHC and with AQUA. ED-specific antibodies did not significantly predicted response. Using AQUA and ID-specific antibody resulted in the best prediction performance with a positive and negative predictive value (PPV/NPV) for responders of 50% and 87%, respectively. EGFR expression with ID-specific antibody and AQUA also predicted responders in EGFR mutated patients. Increased EGFR expression with the ID antibody associated with increased median PFS (11.7 months vs 5.0, Log-rank p=0.034) and OS (38.6 vs 14.9, p=0.040), from gefitinib therapy. Conclusions EGFR protein expression using an ID-specific antibody specifically predicts response to gefitinib in NSCLC patients, including in EGFR mutated patients, and increased PFS/OS from gefitinib. These data suggest that the choice of diagnostic antibody and methodology matters to predict response and outcome to specific therapies. The potential clinical application needs further validation.

Mascaux, Celine; Wynes, Murry W.; Kato, Yasufumi; Tran, Cindy; Asuncion, Bernadette Reyna; Zhao, Jason M.; Gustavson, Mark; Ranger-Moore, Jim; Gaire, Fabien; Matsubayashi, Jun; Nagao, Toshitaka; Yoshida, Koichi; Ohira, Tatuso; Ikeda, Norihiko; Hirsch., Fred R

2011-01-01

42

[The reflection spectrometer and quantitative analysis design].  

PubMed

The reflection spectrometer with optical fibre transmission was designed and used in quantitative analysis. The reflection spectrometry was applied to the determination of reducing sugar in samples based on the reduction reaction of the reducing sugar with Fehling's reagent. The reduction reaction was carried out in a micro-reaction cell, and the reddish colored Cu2O produced was settled at the bottom of the reaction cell. The reflectance R(infinity), which is directly proportional to the amount of Cu2O produced, was measured by the reflection spectrometer. The fundamental principle, effect factors, and experimental conditions of the method were discussed. Linear relationship was obtained in the range of 20-120 microg of reducing sugar. The special features of this method were its simplicity in operation, relatively high sensitivity of determination, and the use of small amount of reagent. Satisfactory results were obtained in its application to the analysis of wine and honey samples. PMID:16883882

Zhang, Ping; Chen, Yong-Heng; Yao, Yan

2006-05-01

43

Materials characterization through quantitative digital image analysis  

SciTech Connect

A digital image analysis system has been developed to allow advanced quantitative measurement of microstructural features. This capability is maintained as part of the microscopy facility at Sandia, Livermore. The system records images digitally, eliminating the use of film. Images obtained from other sources may also be imported into the system. Subsequent digital image processing enhances image appearance through the contrast and brightness adjustments. The system measures a variety of user-defined microstructural features--including area fraction, particle size and spatial distributions, grain sizes and orientations of elongated particles. These measurements are made in a semi-automatic mode through the use of macro programs and a computer controlled translation stage. A routine has been developed to create large montages of 50+ separate images. Individual image frames are matched to the nearest pixel to create seamless montages. Results from three different studies are presented to illustrate the capabilities of the system.

J. Philliber; B. Antoun; B. Somerday; N. Yang

2000-07-01

44

Uncertainty analysis in quantitative risk assessment  

SciTech Connect

Inservice inspection is of great significance to a number of industries, especially such ones as petrochemical and nuclear power. Of the quantitative approaches applied to inservice inspection, failure modes, effects, criticality analysis (FMECA) methodology is recommended. FMECA can provide a straightforward illustration of how risk can be used to prioritize components for inspection (ASME, 1991). But, at present, it has two limitations. One is that it cannot be used in the situation where components have multiple failure modes. The other is that it cannot be used in the situation where the uncertainties in the data of components have nonuniform distributions. In engineering practice, these two situations exist in many cases. In this paper, two methods based on fuzzy set theory are presented to treat these problems. The methods proposed here can be considered as a supplement to FMECA, thus extending its range of applicability.

Quin, S.; Widera, G.E.O. [Marquette Univ., Milwaukee, WI (United States). Dept. of Mechanical and Industrial Engineering

1996-02-01

45

Quantitative analysis of global veterinary human resources.  

PubMed

This analysis of global veterinary personnel was based on the available quantitative data reported by individual countries to international organisations. The analysis begins with a time series of globally reported numbers of veterinarians, starting in the year 1959 (140,391). In 2000 this number reached 691,379. Of this total, 27.77% of veterinarians were working as government officials, 15.38% were working in laboratories, universities and training institutions and 46.33% were working as private practitioners. The ratio of veterinarians to technicians was 1:0.63. The global average of resources serviced by each veterinarian was as follows: 8,760 inhabitants; 189 km2 of land area and 20 km2 of arable land; 1,925 cattle, 242 buffaloes, 87 horses, 1,309 pigs, 1,533 sheep and 20,714 chickens; in abattoirs: 401 slaughtered cattle, 699 slaughtered sheep and 1,674 slaughtered pigs; the production of 336 tonnes (t) of meat, 708 t cow milk and 74 t hen eggs; in international trade: 12 cattle, 23 sheep, 22 pigs, 1 horse, 1,086 chickens, 33 t meat and meat products; 2,289 units of livestock (50 minutes of annual veterinary working time for each unit). These averages were also analysed according to employment categories. The author also discusses factors influencing veterinary personnel analyses and planning. PMID:15005548

Kouba, V

2003-12-01

46

Quantitative risk analysis of urban flooding in lowland areas  

Microsoft Academic Search

Urban flood risk analyses suffer from a lack of quantitative historical data on flooding incidents. Data collection takes place on an ad hoc basis and is usually restricted to severe events. The resulting data deficiency renders quantitative assessment of urban flood risks uncertain. The study reported in this thesis reviews existing approaches to quantitative flood risk analysis and evaluation of

J. A. E. Ten Veldhuis

2010-01-01

47

Histopathological evaluation of liver fibrosis: quantitative image analysis vs semi-quantitative scores  

Microsoft Academic Search

Background\\/Aims: Liver fibrosis is mainly evaluated by qualitative histological examination. Although histological semi-quantitative scores and quantitative determination with image analysis are now possible, these methods have not been fully validated and compared. Therefore, we evaluated these two methods prospectively in 243 patients with chronic liver disease.Methods: The semi-quantitative fibrosis score was evaluated by two independent pathologists, using the Knodell fibrosis

Christophe Pilette; Marie Christine Rousselet; Pierre Bedossa; Daniel Chappard; Frédéric Oberti; Hervé Rifflet; Moussa Y. Maïga; Yves Gallois; Paul Calès

1998-01-01

48

Applying Knowledge of Quantitative Design and Analysis  

ERIC Educational Resources Information Center

|This study compared and contrasted two quantitative scholarly articles in relation to their research designs. Their designs were analyzed by the comparison of research references and research specific vocabulary to describe how various research methods were used. When researching and analyzing quantitative scholarly articles, it is imperative to…

Baskas, Richard S.

2011-01-01

49

QUANTITATIVE TRAIT LOCUS ANALYSIS AND METABOLIC PATHWAYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The development of molecular markers for crop plants has enabled research on the genetic basis of quantitative traits. However, despite more than a decade of these studies, called quantitative trait locus (QTL) analyses, the molecular basis for variation in most agronomic traits is still largely unk...

50

Quantitative analysis of intervertebral disc structure.  

PubMed

A reduction in signal intensity from the nucleus can be a feature of intervertebral disc disease. It has been established that T1 and T2 relaxation times of the nucleus decrease with age and that evidence of disc degeneration can be determined before classical clinical features are apparent. A robust multiple point algorithm has been developed which now enables proton density and T1 and T2 values to be computed for each pixel, providing images which are effectively spatial maps of these parameters. Such high resolution maps have provided quantitative data from volunteers, patients and cadavers. These studies have been carried out with specially constructed coils and the cadaveric information compared with cut sections. The spatial maps revealed detailed anatomic structures including the laminae of the annulus and relative levels of hydration. These levels, which are known to be related to the ability of the disc to withstand compressive loads, can now be measured in vivo. Analysis of the proton density and relaxation times in vivo has demonstrated that both water content and the chemical environment in the nucleus change during aging. The results are consistent with changes in the glycosaminoglycan content and fixed charged density measured by other chemical and physical techniques. Such detailed methods can be used to investigate the effects of aging and disease on disc structure and have enabled observations to be made of the effects of stress on the normal disc. PMID:2980538

Isherwood, I; Prendergast, D J; Hickey, D S; Jenkins, J P

1986-01-01

51

Quantitative methods for ecological network analysis.  

PubMed

The analysis of networks of ecological trophic transfers is a useful complement to simulation modeling in the quest for understanding whole-ecosystem dynamics. Trophic networks can be studied in quantitative and systematic fashion at several levels. Indirect relationships between any two individual taxa in an ecosystem, which often differ in either nature or magnitude from their direct influences, can be assayed using techniques from linear algebra. The same mathematics can also be employed to ascertain where along the trophic continuum any individual taxon is operating, or to map the web of connections into a virtual linear chain that summarizes trophodynamic performance by the system. Backtracking algorithms with pruning have been written which identify pathways for the recycle of materials and energy within the system. The pattern of such cycling often reveals modes of control or types of functions exhibited by various groups of taxa. The performance of the system as a whole at processing material and energy can be quantified using information theory. In particular, the complexity of process interactions can be parsed into separate terms that distinguish organized, efficient performance from the capacity for further development and recovery from disturbance. Finally, the sensitivities of the information-theoretic system indices appear to identify the dynamical bottlenecks in ecosystem functioning. PMID:15556474

Ulanowicz, Robert E

2004-12-01

52

Quantitative color analysis for capillaroscopy image segmentation.  

PubMed

This communication introduces a novel approach for quantitatively evaluating the role of color space decomposition in digital nailfold capillaroscopy analysis. It is clinically recognized that any alterations of the capillary pattern, at the periungual skin region, are directly related to dermatologic and rheumatic diseases. The proposed algorithm for the segmentation of digital capillaroscopy images is optimized with respect to the choice of the color space and the contrast variation. Since the color space is a critical factor for segmenting low-contrast images, an exhaustive comparison between different color channels is conducted and a novel color channel combination is presented. Results from images of 15 healthy subjects are compared with annotated data, i.e. selected images approved by clinicians. By comparison, a set of figures of merit, which highlights the algorithm capability to correctly segment capillaries, their shape and their number, is extracted. Experimental tests depict that the optimized procedure for capillaries segmentation, based on a novel color channel combination, presents values of average accuracy higher than 0.8, and extracts capillaries whose shape and granularity are acceptable. The obtained results are particularly encouraging for future developments on the classification of capillary patterns with respect to dermatologic and rheumatic diseases. PMID:22532162

Goffredo, Michela; Schmid, Maurizio; Conforto, Silvia; Amorosi, Beatrice; D'Alessio, Tommaso; Palma, Claudio

2012-04-25

53

Utilizing multibubble sonophotoluminscence for calcium quantitative analysis in pharmaceuticals  

Microsoft Academic Search

Sonoluminescence can photoexcite fluorescent solutes yielding sonophotoluminescence (SPL). The possibility of applying multibubble sonophotoluminescence (MBSPL) for chemical quantitative analysis is examined in this work. Special devices for MBSPL quantitative detection are designed and fabricated. Calcium contents in pharmaceutical samples are selected to verify the proposed MBSPL analysis. Coupled with flow fluid manifold, high detection frequency, good reproducibility and automatic operation

Yingchun Nie; Jiagen Lv

2008-01-01

54

De novo sequence analysis and intact mass measurements for characterization of phycocyanin subunit isoforms from the blue-green alga Aphanizomenon flos-aquae.  

PubMed

In this work, partial characterization of the primary structure of phycocyanin from the cyanobacterium Aphanizomenon flos-aquae (AFA) was achieved by mass spectrometry de novo sequencing with the aid of chemical derivatization. Combining N-terminal sulfonation of tryptic peptides by 4-sulfophenyl isothiocyanate (SPITC) and MALDI-TOF/TOF analyses, facilitated the acquisition of sequence information for AFA phycocyanin subunits. In fact, SPITC-derivatized peptides underwent facile fragmentation, predominantly resulting in y-series ions in the MS/MS spectra and often exhibiting uninterrupted sequences of 20 or more amino acid residues. This strategy allowed us to carry out peptide fragment fingerprinting and de novo sequencing of several peptides belonging to both alpha- and beta-phycocyanin polypeptides, obtaining a sequence coverage of 67% and 75%, respectively. The presence of different isoforms of phycocyanin subunits was also revealed; subsequently Intact Mass Measurements (IMMs) by both MALDI- and ESI-MS supported the detection of these protein isoforms. Finally, we discuss the evolutionary importance of phycocyanin isoforms in cyanobacteria, suggesting the possible use of the phycocyanin operon for a correct taxonomic identity of this species. PMID:19053161

Rinalducci, Sara; Roepstorff, Peter; Zolla, Lello

2009-04-01

55

`Quantitative' and `Qualitative' Research: An Analysis  

Microsoft Academic Search

It is widely believed that there is a clear distinction between `quantitative' and `qualitative' research, and these embedded or institutionalised terms profoundly affect the practice of such research. In this article the clarity and\\/or usefulness of the distinction is challenged together with the whole idea that there are given `methodologies' for research. Almost everything turns on conceptual clarity in relation

John B. Wilson; Samuel M. Natale

2001-01-01

56

Quantitative risk analysis of oil storage facilities in seismic areas  

Microsoft Academic Search

Quantitative risk analysis (QRA) of industrial facilities has to take into account multiple hazards threatening critical equipment. Nevertheless, engineering procedures able to evaluate quantitatively the effect of seismic action are not well established. Indeed, relevant industrial accidents may be triggered by loss of containment following ground shaking or other relevant natural hazards, either directly or through cascade effects (‘domino effects’).The

Giovanni Fabbrocino; Iunio Iervolino; Francesca Orlando; Ernesto Salzano

2005-01-01

57

Database design and implementation for quantitative image analysis research  

Microsoft Academic Search

Quantitative image analysis (QIA) goes beyond sub- jective visual assessment to provide computer measurements of the image content, typically following image segmentation to iden- tify anatomical regions of interest (ROIs). Commercially available picture archiving and communication systems focus on storage of image data. They are not well suited to efficient storage and mining of new types of quantitative data. In

Matthew S. Brown; Sumit K. Shah; Richard C. Pais; Yeng-zhong Lee; Michael F. Mcnitt-gray; Jonathan G. Goldin; Alfonso F. Cardenas; Denise R. Aberle

2005-01-01

58

Poly[tri-?-aqua-di-aqua-?-phosphono-formato-cobalt(II)sodium  

PubMed Central

The title complex, [CoNa(CO5P)(H2O)5]n, was obtained by reacting sodium phosphono­formate with cobalt nitrate. The complex contains cobalt(II) and sodium ions, which are bridged by the O atoms of two aqua ligands. The CoII ion is octahedrally coordinated by three phosphonoformato ligands (one bi- and the other monodentate) and by two O atoms from the bridging aqua ligands. The sodium cation is hexa­coordinated by six O atoms from four bridging and two terminal aqua ligands. The complex mol­ecules are linked to give a three-dimensional structure by phosphono­formate ligands bridging CoII atoms and water mol­ecules establishing cobalt–sodium bridges. O—H?O hydrogen bonding between the aqua ligands and all O atoms of the phosphono­formato ligand and neighbouring aqua ligands help to consolidate the packing.

Luo, Xu-Jian; Zhang, Xiu-Qing

2013-01-01

59

Quantitative Analysis of Early Seismograph Recordings  

Microsoft Academic Search

Seismograms are the most comprehensive and quantitative documents of ground motion produced by earthquakes. First preserved\\u000a records account for more than 100 years of instrumental seismology already, outperforming the time-span covered by modern\\u000a broad-band seismic networks. But their uniqueness, as a document, prior to the generalization of massive methods of copy and\\u000a distribution, limits the usability and availability of the

J. Batlló; D. Stich; R. Macià

60

Quantitative analysis of comparative genomic hybridization  

SciTech Connect

Comparative genomic hybridization (CGH) is a new molecular cytogenetic method for the detection of chromosomal imbalances. Following cohybridization of DNA prepared from a sample to be studied and control DNA to normal metaphase spreads, probes are detected via different fluorochromes. The ratio of the test and control fluorescence intensities along a chromosome reflects the relative copy number of segments of a chromosome in the test genome. Quantitative evaluation of CGH experiments is required for the determination of low copy changes, e.g., monosomy or trisomy, and for the definition of the breakpoints involved in unbalanced rearrangements. In this study, a program for quantitation of CGH preparations is presented. This program is based on the extraction of the fluorescence ratio profile along each chromosome, followed by averaging of individual profiles from several metaphase spreads. Objective parameters critical for quantitative evaluations were tested, and the criteria for selection of suitable CGH preparations are described. The granularity of the chromosome painting and the regional inhomogeneity of fluorescence intensities in metaphase spreads proved to be crucial parameters. The coefficient of variation of the ratio value for chromosomes in balanced state (CVBS) provides a general quality criterion for CGH experiments. Different cutoff levels (thresholds) of average fluorescence ratio values were compared for their specificity and sensitivity with regard to the detection of chromosomal imbalances. 27 refs., 15 figs., 1 tab.

Manoir, S. du; Bentz, M.; Joos, S. [Abteilung Organisation komplexer Genome, Heidelberg (Germany)]|[Institut fuer Humangenetik, Heidelberg (Germany)] [and others

1995-01-01

61

Quantitative analysis of comparative genomic hybridization.  

PubMed

Comparative genomic hybridization (CGH) is a new molecular cytogenetic method for the detection of chromosomal imbalances. Following cohybridization of DNA prepared from a sample to be studied and control DNA to normal metaphase spreads, probes are detected via different fluorochromes. The ratio of the test and control fluorescence intensities along a chromosome reflects the relative copy number of segments of a chromosome in the test genome. Quantitative evaluation of CGH experiments is required for the determination of low copy changes, e.g., monosomy or trisomy, and for the definition of the breakpoints involved in unbalanced rearrangements. In this study, a program for quantitation of CGH preparations is presented. This program is based on the extraction of the fluorescence ratio profile along each chromosome, followed by averaging of individual profiles from several meta phase spreads. Objective parameters critical for quantitative evaluations were tested, and the criteria for selection of suitable CGH preparations are described. The granularity of the chromosome painting and the regional inhomogeneity of fluorescence intensities in metaphase spreads proved to be crucial parameters. The coefficient of variation of the ratio value for chromosomes in balanced state (CVBS) provides a general quality criterion for CGH experiments. Different cutoff levels (thresholds) of average fluorescence ratio values were compared for their specificity and sensitivity with regard to the detection of chromosomal imbalances. PMID:7705182

du Manoir, S; Schröck, E; Bentz, M; Speicher, M R; Joos, S; Ried, T; Lichter, P; Cremer, T

1995-01-01

62

A flow cytometer based protocol for quantitative analysis of bloom-forming cyanobacteria (Microcystis) in lake sediments.  

PubMed

A quantitative protocol for the rapid analysis of Microcystis cells and colonies in lake sediment was developed using a modified flow cytometer, the CytoSense. For cell enumeration, diluted sediment samples containing Microcystis were processed with sonication to disintegrate colonies into single cells. An optimized procedure suggested that 5 mg dw (dry weight)/mL dilution combined with 200 W x 2 min sonication yielded the highest counting efficiency. Under the optimized determination conditions, the quantification limit of this protocol was 3.3 x 10(4) cells/g dw. For colony analysis, Microcystis were isolated from the sediment by filtration. Colony lengths measured by flow cytometry were similar to those measured by microscopy for the size range of one single cell to almost 400 microm in length. Moreover, the relationship between colony size and cell number was determined for three Microcystis species, including Microcystis flos-aquae, M. aeruginosa and M. wessenbergii. Regression formulas were used to calculate the cell numbers in different-sized colonies. The developed protocol was applied to field sediment samples from Lake Taihu. The results indicated the potential and applicability of flow cytometry as a tool for the rapid analysis of benthic Microcystis. This study provided a new capability for the high frequency monitoring of benthic overwintering and population dynamics of this bloom-forming cyanobacterium. PMID:23520881

Zhou, Quan; Chen, Wei; Zhang, Huiyong; Peng, Liang; Liu, Liming; Han, Zhiguo; Wan, Neng; Li, Lin; Song, Lirong

2012-01-01

63

Research in quantitative microscopic X-ray fluorescence analysis  

Microsoft Academic Search

A feasibility study of quantitative elemental microanalysis of biological materials and glass samples by microbeam X-ray fluorescence spectroscopy was completed. The research included testing the homogeneity of existing standards for X-ray fluorescence calibration and verification of a fundamental parameters method for quantitative analysis. The goal was to evaluate the X-ray fluorescence spectrometer as a tool for elemental analysis at the

M. Lankosz; M. Szczerbowska-Boruchowska; J. Chwiej; J. Ostachowicz; A. Simionovici; S. Bohic

2004-01-01

64

Quantitative and qualitative analysis of institutional and professional identity  

Microsoft Academic Search

This paper focuses on the analysis of two types of identity construction in a corpus of professional speeches, namely institutional identity of the company and professional identity of the speaker. Since the corpus under study is rather large, three interesting speeches are selected on the basis of quantitative pronoun analysis. Discourse analysis of this subcorpus reveals the complexity of the

Van De Mieroop D

2004-01-01

65

Quantitative data analysis of ESAR data  

NASA Astrophysics Data System (ADS)

A synthetic aperture radar (SAR) data processing uses the backscattered electromagnetic wave to map radar reflectivity of the ground surface. The polarization property in radar remote sensing was used successfully in many applications, especially in target decomposition. This paper presents a case study to the experiments which are performed on ESAR L-Band full polarized data sets from German Aerospace Center (DLR) to demonstrate the potential of coherent target decomposition and the possibility of using the weather radar measurement parameter, such as the differential reflectivity and the linear depolarization ratio to obtain the quantitative information of the ground surface. The raw data of ESAR has been processed by the SAR simulator developed using MATLAB program code with Range-Doppler algorithm.

Phruksahiran, N.; Chandra, M.

2013-07-01

66

Quantitative Electroencephalography (QEEG) and Neuropsychological Syndrome Analysis  

Microsoft Academic Search

The ideographic, syndrome analysis and the nomothetic, standardized test battery approaches to neuropsychological assessment are compared and contrasted within the context of advances in noninvasive technology readily available for use within the examiner's office. By demonstrating the relative strengths and benefits of syndrome analysis, it is suggested that this approach provides a thorough and efficient method of neuropsychological assessment. Subsequently,

B. V. Shenal; R. D. Rhodes; T. M. Moore; D. A. Higgins; D. W. Harrison

2001-01-01

67

Qualitative and quantitative analysis of DNA fragmentation using digital imaging.  

PubMed

Apoptosis is an important and common pathway of cellular death. Differentiation from cellular necrosis and quantitation of apoptosis within the milieu of necrosis are analytical challenges. We describe the use of the RIT120 digital imaging software package for quantitative and qualitative analysis of apoptotic DNA ladders induced by a variety of agents, such as serum, tumor necrosis factor-alpha, transforming growth factor-beta1, and nitric oxide. Autoradiographs of DNA ladders are densitometrically scanned to yield a set of curves with peaks corresponding to specific DNA fragments, thereby allowing quantitative subtraction of concurrent DNA degradation from necrotic death. Integration of the areas specifically under the peaks yields a quantitative measure of apoptosis. We provide a useful, rapid, and objective means to quantitate apoptosis, using relatively inexpensive hardware and software. PMID:9245431

Vodovotz, Y; Hsing, A; Cook, J A; Miller, R W; Wink, D A; Ritt, D M; Mitchell, J B; Danielpour, D

1997-08-01

68

Standardization of Central Off-Line Quantitative Image Analysis: Implications from Experiences with Quantitative Coronary Angiography  

Microsoft Academic Search

Developments in both medical equipment and software provide the opportunity to obtain more detailed, and in many instances direct digital images, i.e. not using film or video, that can be used for off-line quantitative analysis. As a result, the use of imaging data besides clinical data as a primary end point in clinical trials has nowadays become more acceptable. However,

Anton W. M. van Weert; Jacques Lésperance; Johan H. C. Reiber

2001-01-01

69

A QUANTITATIVE ANALYSIS OF DISTANT OPEN CLUSTERS  

SciTech Connect

The oldest open star clusters are important for tracing the history of the Galactic disk, but many of the more distant clusters are heavily reddened and projected against the rich stellar background of the Galaxy. We have undertaken an investigation of several distant clusters (Berkeley 19, Berkeley 44, King 25, NGC 6802, NGC 6827, Berkeley 52, Berkeley 56, NGC 7142, NGC 7245, and King 9) to develop procedures for separating probable cluster members from the background field. We next created a simple quantitative approach for finding approximate cluster distances, reddenings, and ages. We first conclude that with the possible exception of King 25 they are probably all physical clusters. We also find that for these distant clusters our typical errors are about {+-}0.07 in E(B - V), {+-}0.15 in log(age), and {+-}0.25 in (m - M){sub o}. The clusters range in age from 470 Myr to 7 Gyr and range from 7.1 to 16.4 kpc from the Galactic center.

Janes, Kenneth A.; Hoq, Sadia [Astronomy Department, Boston University, Boston, MA 02215 (United States)

2011-03-15

70

Quantitative analysis of oblique ocular movements.  

PubMed

In the present study, oblique saccadic eye movements in the orthogonal and oblique directions were investigated in 10 normal subjects, and a computer program was used to accomplish quantitative assessment of oblique eye movements. Eye movements were recorded with direct-current electronystagmography (DC-ENG) and a 12-bit analog to digital converter was used to collect analog data of horizontal and vertical eye position, and stimulus signals at a sampling rate of 200 Hz. The oblique eye movement was displayed two-dimentionally on a high-resolution color graphic terminal for the evaluation of the trace of eye movements, and the peak velocity and the amplitude of the horizontal, vertical and oblique saccades were calculated. It was frequently found that the tracing line in the oblique saccadic eye movement was not completely straight, but loosely curved. The velocity of the vertical component of the oblique saccade was much lower than that of the horizontal component. This suggests that oblique saccades might be made by synchronized but independent vertical and horizontal pulse generators, and the system developed this time might be very useful for investigation of oblique eye movements in both the clinical and physiological field. PMID:8203217

Okuyama, T; Nakamura, T; Aoyagi, M; Kanayama, R; Ohki, M; Sano, R; Kimura, Y; Koike, Y

1994-01-01

71

Quantitative infrared analysis of hydrogen fluoride  

SciTech Connect

This work was performed at the Portsmouth Gaseous Diffusion Plant where hydrogen fluoride is produced upon the hydrolysis of UF{sub 6}. This poses a problem for in this setting and a method for determining the mole percent concentration was desired. HF has been considered to be a non-ideal gas for many years. D. F. Smith utilized complex equations in his HF studies in the 1950s. We have evaluated HF behavior as a function of pressure from three different perspectives. (1) Absorbance at 3877 cm{sup -1} as a function of pressure for 100% HF. (2) Absorbance at 3877 cm{sup -1} as a function of increasing partial pressure HF. Total pressure = 300 mm HgA maintained with nitrogen. (3) Absorbance at 3877 cm{sup -1} for constant partial pressure HF. Total pressure is increased to greater than 800 mm HgA with nitrogen. These experiments have shown that at partial pressures up to 35mm HgA, HIF follows the ideal gas law. The absorbance at 3877 cm{sup -1} can be quantitatively analyzed via infrared methods.

Manuta, D.M.

1997-04-01

72

Quantitative proteomic analysis of dystrophic dog muscle.  

PubMed

Duchenne muscular dystrophy (DMD) is caused by null mutations in the dystrophin gene, leading to progressive and unrelenting muscle loss. Although the genetic basis of DMD is well resolved, the cellular mechanisms associated with the physiopathology remain largely unknown. Increasing evidence suggests that secondary mechanisms, as the alteration of key signaling pathways, may play an important role. In order to identify reliable biomarkers and potential therapeutic targets, and taking advantage of the clinically relevant Golden Retriever Muscular Dystrophy (GRMD) dog model, a proteomic study was performed. Isotope-coded affinity tag (ICAT) profiling was used to compile quantitative changes in protein expression profiles of the vastus lateralis muscles of 4-month old GRMD vs healthy dogs. Interestingly, the set of under-expressed proteins detected appeared primarily composed of metabolic proteins, many of which have been shown to be regulated by the transcriptional peroxisome proliferator-activated receptor-gamma co-activator 1 alpha (PGC-1?). Subsequently, we were able to showed that PGC1-? expression is dramatically reduced in GRMD compared to healthy muscle. Collectively, these results provide novel insights into the molecular pathology of the clinically relevant animal model of DMD, and indicate that defective energy metabolism is a central hallmark of the disease in the canine model. PMID:21410286

Guevel, Laetitia; Lavoie, Jessie R; Perez-Iratxeta, Carolina; Rouger, Karl; Dubreil, Laurence; Feron, Marie; Talon, Sophie; Brand, Marjorie; Megeney, Lynn A

2011-03-29

73

The quantitative failure of human reliability analysis  

SciTech Connect

This philosophical treatise argues the merits of Human Reliability Analysis (HRA) in the context of the nuclear power industry. Actually, the author attacks historic and current HRA as having failed in informing policy makers who make decisions based on risk that humans contribute to systems performance. He argues for an HRA based on Bayesian (fact-based) inferential statistics, which advocates a systems analysis process that employs cogent heuristics when using opinion, and tempers itself with a rational debate over the weight given subjective and empirical probabilities.

Bennett, C.T.

1995-07-01

74

Quantitive and Sociological Analysis of Blog Networks  

NASA Astrophysics Data System (ADS)

This paper examines the emerging phenomenon of blogging, using three different Polish blogging services as the base of the research. Authors show that blog networks are sharing their characteristics with complex networks (gamma coefficients, small worlds, cliques, etc.). Elements of sociometric analysis were used to prove existence of some social structures in the blog networks.

Bachnik, W.; Szymczyk, S.; Leszczynski, S.; Podsiadlo, R.; Rymszewicz, E.; Kurylo, L.; Makowiec, D.; Bykowska, B.

2005-10-01

75

Quantitive and Sociological Analysis of Blog Networks  

Microsoft Academic Search

This paper examines the emerging phenomenon of blogging, using three different Polish blogging services as the base of the research. Authors show that blog networks are sharing their characteristics with complex networks (gamma coefficients, small worlds, cliques, etc.). Elements of sociometric analysis were used to prove existence of some social structures in the blog networks.

Wiktor Bachnik; Stanislaw Szymczyk; S. Leszczynski; Rafal Podsiadlo; Ewa Rymszewicz; Lukasz Kurylo; Danuta Makowiec; Beata Bykowska

2005-01-01

76

A Comparative Assessment of Greek Universities' Efficiency Using Quantitative Analysis  

ERIC Educational Resources Information Center

|In part due to the increased demand for higher education, typical evaluation frameworks for universities often address the key issue of available resource utilisation. This study seeks to estimate the efficiency of 20 public universities in Greece through quantitative analysis (including performance indicators, data envelopment analysis (DEA) and…

Katharaki, Maria; Katharakis, George

2010-01-01

77

Measuring Interest Group Influence Using Quantitative Text Analysis  

Microsoft Academic Search

The analysis of interest group influence is crucial in order to explain policy outcomes and to assess the democratic legitimacy of the European Union. However, owing to methodological difficulties in operationalizing influence, only few have studied it. This article therefore proposes a new approach to the measurement of influence, drawing on quantitative text analysis. By comparing interest groups’ policy positions

Heike Klüver

2009-01-01

78

A quantitative risk analysis approach to port hydrocarbon logistics  

Microsoft Academic Search

A method is presented that allows quantitative risk analysis to be performed on marine hydrocarbon terminals sited in ports. A significant gap was identified in the technical literature on QRA for the handling of hazardous materials in harbours published prior to this work. The analysis is extended to tanker navigation through port waters and loading and unloading facilities. The steps

A. Ronza; S. Carol; V. Espejo; J. A. Vílchez; J. Arnaldos

2006-01-01

79

AQuA: an automatic pipeline for fast transients detection  

NASA Astrophysics Data System (ADS)

AQuA (Automatic QUick Analysis) is a software designed to manage data reduction and prompt detection of near infra-red (NIR) afterglows of GRB triggered by the dedicated instruments onboard satellites and observed with the robotic telescope REM. NIR observations of GRBs early afterglow are of crucial importance for GRBs science, revealing even optical obscured or high redshift events. The core of the pipeline is an algorithm for automatic transient detection, based on a decision tree that is continuously upgraded through a Bayesian estimator (DecOAR). It assigns to every transient candidate different reliability coefficients and delivers an alert when a transient is found above the reliability threshold.

Testa, Vincenzo; Antonelli, Lucio Angelo; Di Paola, Andrea; Melandri, Andrea; Calzoletti, Luca; Cunniffe, Ronan; Zerbi, Filippo M.; Chincarini, Guido; Rodono, Marcello; Conconi, Paolo; Covino, Stefano; Cutispoto, Giuseppe; Molinari, Emilio; Tosti, Gino

2004-09-01

80

Quantitative Analysis in Nuclear Medicine Imaging  

NASA Astrophysics Data System (ADS)

This book provides a review of image analysis techniques as they are applied in the field of diagnostic and therapeutic nuclear medicine. Driven in part by the remarkable increase in computing power and its ready and inexpensive availability, this is a relatively new yet rapidly expanding field. Likewise, although the use of radionuclides for diagnosis and therapy has origins dating back almost to the discovery of natural radioactivity itself, radionuclide therapy and, in particular, targeted radionuclide therapy has only recently emerged as a promising approach for therapy of cancer and, to a lesser extent, other diseases.

Zaidi, Habib

81

Aquaculture Network Information Center (AquaNIC)  

NSDL National Science Digital Library

Links to national and international level electronic resources for aquaculture information including: scientific institutions, agencies, industries, news, newsletters, job listings, discussion groups, courses, species, publications, and commercial products. Goals include: providing self-paced aquaculture instruction to the aquaculture industry, and obtaining user input in directing AquaNIC services. A version in Spanish is being prepared.

82

First report on cylindrospermopsin producing Aphanizomenon flos-aquae (Cyanobacteria) isolated from two German lakes.  

PubMed

Three single-filament isolates of Aphanizomenon flos-aquae from two German lakes were found to produce remarkable amounts of the cyanobacterial hepatotoxin cylindrospermopsin (CYN). CYN-synthesis of the strains were evidenced both by LC-MS/MS analysis and detection of PCR products of gene fragments which are implicated in the biosynthesis of the toxin. The strains contain CYN in the range of 2.3-6.6 mg g(-1) of cellular dry weight. To our knowledge this is the first report of CYN in A. flos-aquae. PMID:16356522

Preussel, Karina; Stüken, Anke; Wiedner, Claudia; Chorus, Ingrid; Fastner, Jutta

2005-12-13

83

Control of separation and quantitative analysis by GC-FTIR  

NASA Astrophysics Data System (ADS)

Software for 3-D representations of the 'Absorbance-Wavenumber-Retention time' is used to control the quality of the GC separation. Spectral information given by the FTIR detection allows the user to be sure that a chromatographic peak is 'pure.' The analysis of peppermint essential oil is presented as an example. This assurance is absolutely required for quantitative applications. In these conditions, we have worked out a quantitative analysis of caffeine. Correlation coefficients between integrated absorbance measurements and concentration of caffeine are discussed at two steps of the data treatment.

Semmoud, A.; Huvenne, Jean P.; Legrand, P.

1992-03-01

84

Quantitative risk-benefit analysis of natalizumab  

PubMed Central

Objective: To model the long-term risks and benefits of natalizumab in individuals with relapsing multiple sclerosis (MS). Methods: We created a Markov model to evaluate treatment effects on reducing relapses and slowing disease progression using published natural history data and clinical trial results. Health changes, measured in quality-adjusted life-years (QALYs), were based on patient health preferences. Patient cohorts treated with no disease-modifying treatment, natalizumab, subcutaneous interferon ?-1a, and a theoretical “perfect” MS treatment were modeled. Sensitivity analysis was used to explore model uncertainty, including varying risks of developing progressive multifocal leukoencephalopathy (PML). Results: Treatment with natalizumab resulted in 9.50 QALYs over a 20-year time horizon, a gain of 0.80 QALYs over the untreated cohort and 0.38 QALYs over interferon ?-1a. The health loss due to PML was small (?0.06 QALYs). To offset natalizumab’s incremental health gain over interferon ?-1a, the risk had to increase from 1 to 7.6 PML per 1,000 patients treated over 17.9 months. The “perfect” MS treatment accumulated 10.59 QALYs over the 20-year time horizon, 1.89 QALYs above the untreated cohort. Interferon ?-1a resulted in greater QALY gains compared with natalizumab if natalizumab’s relative relapse reduction was reduced from 68% to 35% or if interferon ?-1a’s relative reduction was increased from 32% to 65%. Conclusions: A more than sevenfold increase in actual risk of progressive multifocal leukoencephalopathy was required to decrease natalizumab’s health gain below that of interferon ?-1a, and there remains considerable room for additional gains in health (>50%) beyond those already achieved with current therapies. GLOSSARY AFFIRM = Natalizumab Safety and Efficacy in Relapsing Remitting Multiple Sclerosis; EDSS = Expanded Disability Status Scale; FDA = Food and Drug Administration; IFN = interferon; MS = multiple sclerosis; PML = progressive multifocal leukoencephalopathy; PRISMS = Prevention of Relapses and Disability by Interferon Beta-1a Subcutaneously in Multiple Sclerosis; QALY = quality-adjusted life-year; TOUCH = Tysabri Outreach: Unified Commitment to Health; TYGRIS = Tysabri Global Observation Program in Safety.

Thompson, J P.; Noyes, K; Dorsey, E R.; Schwid, S R.; Holloway, R G.

2008-01-01

85

Quantitative analysis of human immunoregulatory cytokines by electrochemiluminescence method.  

PubMed

Quantitative analysis of human immunoregulatory cytokines in physiological media and cell cultures plays an important role in fundamental and clinical research. Here we describe the quantification of interleukin (IL)-2, IL-4, IL-10 and interferon-gamma (IFN-gamma) in human serum and peripheral blood mononuclear cell (PBMC)-conditioned medium by electrochemiluminescence method (ECL). We demonstrate that this approach allows to detect cytokine concentration from 1 pg/ml. The high sensitivity in combination with accuracy and wide range of determined concentration indicates that ECL meets the standards of quantitative analysis of cytokines. Simplicity and short time of procedure, small assay volume and high reproducibility make ECL method competitive in practical use with conventional quantitative methods of cytokine detection. PMID:12667672

Sennikov, Sergey V; Krysov, Sergey V; Injelevskaya, Tatiana V; Silkov, Alexandr N; Grishina, Lyubov V; Kozlov, Vladimir A

2003-04-01

86

Lung image segmentation and registration for quantitative image analysis  

Microsoft Academic Search

Functional images obtained PET and\\/or SPECT become more useful when those images are provided with detail anatomical information obtained by X ray CT or MRI. A series of image processing including image registration and segmentation is presented for quantitative analysis of functional images. A clinical application described in the paper is to evaluate the effect of radiation therapy for lung

Hideaki Haneishi; Hidenori Ue; Noriaki Takita; Hinako Toyama; Tadaaki Miyamoto; Naoyohi Yamamoto; Yutaka Mori

2001-01-01

87

Issues Related to Data Analysis and Quantitative Methods in PER  

NSDL National Science Digital Library

This paper, presented at the 2002 Physics Education Research Conference, offers authors' discussion of some issues that always arise, implicitly or explicitly, when conducting quantitative research and carrying out data analysis in Physics Education Research. (Most are relevant for qualitative research as well.)

Meltzer, David E.

2006-12-06

88

Issues Related to Data Analysis and Quantitative Methods in PER  

NSDL National Science Digital Library

This paper, presented at the 2002 Physics Education Research Conference, offers authors' discussion of some issues that always arise, implicitly or explicitly, when conducting quantitative research and carrying out data analysis in Physics Education Research. (Most are relevant for qualitative research as well.)

Meltzer, David (David Elliott)

2010-07-22

89

Quantitative analysis methodology in safety-critical microprocessor applications  

Microsoft Academic Search

In this paper, a quantitative methodology to be considered in safety-critical microprocessor applications is proposed. Some important aspects that must be considered in safety analysis work are discussed. We discuss how to evaluate the dangerous detectable and undetectable system failure rates in a single microprocessor board and the mean time to unsafe failure (MTTUF) of a critical system. The proposed

J. B Camargo; E Canzian; J. R Almeida; S. M Paz; B. A Basseto

2001-01-01

90

Quantitative and Qualitative Analysis of Rhinovirus Infection in Bronchial Tissues  

Microsoft Academic Search

Althoughrhinovirus(RV)infectionscancauseasthmaexacerbations and alter lower airway inflammation and physiology, it is unclear how important bronchial infection is to these processes. To study the kinetics, location, and frequency of RV appearance in lower airway tissues during an acute infection, immunohistochemistry and quantitative polymerase chain reaction analysis were used to analyze the presence of virus in cells from nasal lavage, sputum, bronchoalveolar lavage,

Anne G. Mosser; Rose Vrtis; Lacinda Burchell; Wai-Ming Lee; Claire R. Dick; Elizabeth Weisshaar; Diane Bock; Cheri A. Swenson; Richard D. Cornwell; Keith C. Meyer; Nizar N. Jarjour; William W. Busse; James E. Gern

91

Quantitative estimation of calcite in limestones by differential thermal analysis  

Microsoft Academic Search

A quantitative method is presented for the estimation of calcite in limestones by differential thermal analysis, using calcium hydroxide as an internal standard. The effects of variations due to particle size and impurities such as quartz, iron oxide, organic material, dolomite, magnesite, gypsum and phosphates are discussed.

K. Jehan; M. A. Qaiser; A. H. Khan

1972-01-01

92

Quantitative analysis of thallium-201 myocardial emission computed tomography  

SciTech Connect

The clinical usefulness of quantitative analysis of exercise thallium-201 myocardial emission computed tomography (ECT) was evaluated in twenty coronary artery disease patients and 10 normal controls. Longaxial and shortaxial myocardial images of left ventricle were interpreted quantitatively using circumferential profile analysis and two types of abnormality were studied: (1) diminished initial distribution (stress defect) and (2) slow washout of thallium-201, evidenced by patients' initial thallium-201 uptake and 3-hour washout rate profiles falling below the normal limits, respectively. Two diagnostic criteria, stress defect criterion and combined one of stress defect and slow washout, were used to detect significant coronary artery lesions (greater than or equal to75% luminal narrowing). The ischemic volume was also evaluated with quantitative analysis of thallium-201 ECT. The diagnostic accuracy of stress defect criterion was 95% in left ascending, 90% in right coronary and 78% in left circumflex coronary artery lesions. The combined criterion of stress defect and low washout increased detection sensitivity with moderate loss of specificity for identification of individual coronary artery lesions. The ischemic myocardial volume evaluated with combined criterion was significantly larger in triple vessel than in single vessel disease (p<0.05). It was concluded that quantitative analysis of exercise thallium-201 myocardial ECT images was useful for evaluation of coronary artery lesions.

Okada, M.; Kawai, N.; Yamamoto, S.; Matsushima, H.; Kato, R.; Tanahashi, Y.; Sotobata, I.; Obata, Y.; Sakuma, S.

1984-01-01

93

Quantitative Trait Associated Microarray Gene Expression Data Analysis  

Microsoft Academic Search

Selection on phenotypes may cause genetic change. To understand the relationship between phenotype and gene expres- sion from an evolutionary viewpoint, it is important to study the concordance between gene expression and profiles of phenotypes. In this study, we use a novel method of clustering to identify genes whose expression profiles are related to a quantitative phenotype. Cluster analysis of

Yi Qu; Shizhong Xu

2006-01-01

94

Quantitative analysis of tin and lead in TDI combustion catalyst  

Microsoft Academic Search

A convenient method for quantitative analysis of tin and lead in 2,4—tolylene diisocyanate (TDI) combustion catalyst, which contains Tin, lead and their compounds or complexes, is described. The method consists of decomposition of samples by sodium hydroxide fusion, extraction with hydrochloric acid and complexation by EDTA, followed by titration with zinc chloride standard titration solution, which give rise to a

Li Qin-fang

1997-01-01

95

Analysis of quantitative trait loci that influence animal behavior  

Microsoft Academic Search

Behavioral differences between in- bred strains of mice and rats have a genetic basis that can now be dissected using quantitative trait locus (QTL) analysis. Over the last 10 years, a large number of genetic loci that influence behavior have been mapped. In this article I review what that information has revealed about the genetic architecture of behavior. I show

Jonathan Flint

2003-01-01

96

Quantitative analysis for oleic and petroselinic acids in glyceride oils  

Microsoft Academic Search

A rapid quantitative method for the determination of oleic (9-cis-octadecenoic) and petroselinic (6-cis-octadecenoic) acids\\u000a was required for nutritional research. The methyl esters of these two acids have coincident emergence in GLC separations using\\u000a polyester columns. A method involving oxidation and GLC analysis of the resultant monocarboxylic acids has been developed.

T. M. Mallard; B. M. Craig

1966-01-01

97

Qualitative and quantitative thermoluminescence analysis on irradiated oregano  

Microsoft Academic Search

Thermoluminescence (TL) dosimetry is one of the physical methods used for the identification of irradiated food, suitable for foods from which silicate minerals can be extracted. The aims of the present work were to apply the TL analysis for a qualitative identification of irradiated oregano, and to set up a quantitative procedure to estimate the original treatment dose on the

M. C. D’Oca; A. Bartolotta; M. C. Cammilleri; M. Brai; M. Marrale; A. Triolo; A. Parlato

2007-01-01

98

Quantitative Risk Analysis applied to the Gases Industry  

Microsoft Academic Search

In order to contribute to the risk knowledge that people and the environment can suffer from accidents related to process safety this paper presents a case study of quantitative risk analysis applied to the gases industry. Industry activities such as production, storage or handling related to dangerous materials are complex and highly prone to severe or catastrophic accidents. All these

A. N. Haddad; T. S. Sa; E. B. F. Galante

2009-01-01

99

Control of separation and quantitative analysis by GC-FTIR  

Microsoft Academic Search

Software for 3-D representations of the 'Absorbance-Wavenumber-Retention time' is used to control the quality of the GC separation. Spectral information given by the FTIR detection allows the user to be sure that a chromatographic peak is 'pure.' The analysis of peppermint essential oil is presented as an example. This assurance is absolutely required for quantitative applications. In these conditions, we

A. Semmoud; Jean P. Huvenne; P. Legrand

1992-01-01

100

A quantitative approach for medical device Health Hazard Analysis  

Microsoft Academic Search

Health Hazard Analysis (HHA) is one major type of patient health risk assessment for medical device field performance issue. U.S. Food and Drug Administration (FDA) has an online form, listing the needed information for HHA. In this paper, we will illustrate a quantitative HHA approach, which is structured in a rigorous risk assessment framework, with several critical steps, concepts and

Mingxiao Jiang; Kathy Herzog; Thomas Pepin; Michael D. Baca

2011-01-01

101

Quantitating the subtleties of microglial morphology with fractal analysis  

PubMed Central

It is well established that microglial form and function are inextricably linked. In recent years, the traditional view that microglial form ranges between “ramified resting” and “activated amoeboid” has been emphasized through advancing imaging techniques that point to microglial form being highly dynamic even within the currently accepted morphological categories. Moreover, microglia adopt meaningful intermediate forms between categories, with considerable crossover in function and varying morphologies as they cycle, migrate, wave, phagocytose, and extend and retract fine and gross processes. From a quantitative perspective, it is problematic to measure such variability using traditional methods, but one way of quantitating such detail is through fractal analysis. The techniques of fractal analysis have been used for quantitating microglial morphology, to categorize gross differences but also to differentiate subtle differences (e.g., amongst ramified cells). Multifractal analysis in particular is one technique of fractal analysis that may be useful for identifying intermediate forms. Here we review current trends and methods of fractal analysis, focusing on box counting analysis, including lacunarity and multifractal analysis, as applied to microglial morphology.

Karperien, Audrey; Ahammer, Helmut; Jelinek, Herbert F.

2013-01-01

102

Methodologies for laboratory Laser Induced Breakdown Spectroscopy semi-quantitative and quantitative analysis—A review  

NASA Astrophysics Data System (ADS)

Since its early applications, Laser Induced Breakdown Spectroscopy has been recognized as a useful tool for solid state chemical analysis. However the quantitative accuracy of the technique depends on the complex processes involved in laser induced plasma formation, ablation, atomization, excitation and ion recombination. Problems arising from laser target coupling, matrix effect, fractionation in target vaporization, local thermodynamic equilibrium assumption and interferences from additional air ionization should be properly addressed in order to obtain reliable quantitative results in laboratory to be used as starting point during field campaigns. As selected case studies carried out within the authors' research team show, a proper selection of laser parameters and, in general of experimental conditions, for laboratory data acquisition is required in order to minimize the mentioned problems both in case of calibration curves and calibration free approaches. In particular, the choice of reference samples for measuring calibration curves is of crucial importance in laboratory experiments, in relation both to matrix effect and local thermodynamic equilibrium, to be carried out at comparable conditions in terms of temperature and electron density. A model for the ablation process aimed to the optimization of experimental conditions in some case studies (copper alloys) has been specifically developed in order to account for the target stoichiometry in the plasma. Problems related to the limit of detection for quantitative trace analysis have been considered in analyzing data collected both inside and outside the local thermodynamic equilibrium window, in cases characterized by a fixed contamination threshold.

Fantoni, R.; Caneve, L.; Colao, F.; Fornarini, L.; Lazic, V.; Spizzichino, V.

2008-10-01

103

Quantitative transverse flow assessment using OCT speckle decorrelation analysis  

NASA Astrophysics Data System (ADS)

In this study, we demonstrate the use of inter-Ascan speckle decorrelation analysis of optical coherence tomography (OCT) to assess fluid flow. This method allows quantitative measurement of fluid flow in a plane normal to the scanning beam. To validate this method, OCT images were obtained from a micro fluid channel with bovine milk flowing at different speeds. We also imaged a blood vessel from in vivo animal models and performed speckle analysis to asses blood flow.

Liu, Xuan; Huang, Yong; Ramella-Roman, Jessica C.; Kang, Jin U.

104

A microcomputer based automated, quantitative coronary angiographic analysis system  

Microsoft Academic Search

Rapid and accurate assessment of coronary artery stenotic severity is important in therapy and understanding of coronary artery\\u000a disease. Since automated systems minimize prejudiceand variations in analysis, we developed an automated, quantitative coronary\\u000a analysis system utilizing an IBM PC-XT computer. Film images (35 mm) were cine-to-video converted and subsequently digitized\\u000a by an IBM PC-XT computer. Given an approximate center line,

William P. Santamore; Frederic R. Kahl; Michael A. Kutcher; Michael Negin; James L. Whiteman; Jeffrey P. Kase; William C. Little

1988-01-01

105

Quantitative Clay Mineralogical Analysis of Soils and Sediments  

Microsoft Academic Search

THE objective of this paper is to present flow sheets for a system of quantitative minera- logical analysis of clays of soils and sediments and to show representative results. Selec- tive dissolution analysis by the NasSsOv-HC1-NaOH procedure yields the quartz and feldspar contents (0 to 63%) and differentiates feldspar K from mica K. The NaOH- thermal system of selective dissolution

C. A. Alexiades; M. L. JACKSO

1966-01-01

106

Quantitative analysis of culture using millions of digitized books  

PubMed Central

We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of ‘culturomics’, focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. ‘Culturomics’ extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities.

Michel, Jean-Baptiste; Shen, Yuan Kui; Aiden, Aviva P.; Veres, Adrian; Gray, Matthew K.; Pickett, Joseph P.; Hoiberg, Dale; Clancy, Dan; Norvig, Peter; Orwant, Jon; Pinker, Steven; Nowak, Martin A.; Aiden, Erez Lieberman

2011-01-01

107

Quantitative analysis of fracture surface by roughness and fractal method  

SciTech Connect

In recent years there has been extensive research and great development in Quantitative Fractography, which acts as an integral part of fractographic analysis. A prominent technique for studying the fracture surface is based on fracture profile generation and the major means for characterizing the profile quantitatively are roughness and fractal methods. By this way, some quantitative indexes such as the roughness parameters R{sub L} for profile and R{sub S} for surface, fractal dimensions D{sub L} for profile and D{sub S} for surface can be measured. Given the relationships between the indexes and the mechanical properties of materials, it is possible to achieve the goal of protecting materials from fracture. But, as the case stands, the theory and experimental technology of quantitative fractography are still imperfect and remain to be studied further. Recently, Gokhale and Underwood et al have proposed an assumption-free method for estimating the surface roughness by vertically sectioning the fracture surface with sections at an angle of 120 deg with each other, which could be expressed as follows: R{sub S} = {ovr R{sub L}{center_dot}{Psi}} where {Psi} is the profile structure factor. This method is based on the classical sterological principles and verified with the aid of computer simulations for some ruled surfaces. The results are considered to be applicable to fracture surfaces with any arbitrary complexity and anisotropy. In order to extend the detail applications to this method in quantitative fractography, the authors made a study on roughness and fractal methods dependent on this method by performing quantitative measurements on some typical low-temperature impact fractures.

Li, X.W.; Tian, J.F.; Kang, Y.; Wang, Z.G. [Academia Sinica, Shenyang (China). State Key Lab. for Fatigue and Fracture of Materials

1995-09-01

108

Quantitative analysis of pedestrian counterflow in a cellular automaton model.  

PubMed

Pedestrian dynamics exhibits various collective phenomena. Here, we study bidirectional pedestrian flow in a floor field cellular automaton model. Under certain conditions, lane formation is observed. Although it has often been studied qualitatively, e.g., as a test for the realism of a model, there are almost no quantitative results, either empirically or theoretically. As basis for a quantitative analysis, we introduce an order parameter which is adopted from the analysis of colloidal suspensions. This allows us to determine a phase diagram for the system where four different states (free flow, disorder, lanes, gridlock) can be distinguished. Although the number of lanes formed is fluctuating, lanes are characterized by a typical density. It is found that the basic floor field model overestimates the tendency towards a gridlock compared to experimental bounds. Therefore, an anticipation mechanism is introduced which reduces the jamming probability. PMID:23005183

Nowak, Stefan; Schadschneider, Andreas

2012-06-21

109

Quantitative analysis of parallel nanowire array assembly by dielectrophoresis.  

PubMed

We describe an assembly technique useful for generating ordered arrays of nanowires (NWs) between electrodes via dielectrophoresis (DEP) and an analysis technique useful for extracting quantitative information about the local electric fields and dielectrophoretic forces from video microscopy data. By tuning the magnitude of the applied electric fields such that the attractive forces on the NWs are of the same order of magnitude as the Brownian forces, and by taking advantage of the inter-NW repulsive forces during DEP, NWs can be assembled into parallel arrays with high reproducibility. By employing a particle-tracking code and analysis of NW motion, we demonstrate a method for quantitative mapping of the dielectrophoretic torques and NW-surface interactions as a function of position on the substrate, which allows a more complete understanding of the dynamics of the assembly and the ability to control these parameters for precise assembly. PMID:21161112

Papadakis, Stergios J; Hoffmann, Joan A; Deglau, David; Chen, Andrew; Tyagi, Pawan; Gracias, David H

2010-12-16

110

Quantitative analysis of lipids by thin-layer chromatography  

Microsoft Academic Search

A procedure is described for the quantitative analysis of neutral and phospholipids by thinlayer chromatography (TLC) employing\\u000a densitometry. The chromatophates are prepared with the usual solvent systems. The spots are charred under standard conditions\\u000a and analyzed with a Photovolt Corp. densitometer equipped with a special stage designed for holding 20×20 cm chromatoplates.\\u000a Each spot on the chromatoplate gives a peak

M. L. Blank; J. A. Schmit; O. S. Privett

1964-01-01

111

Quantitative analysis of thuringiensin by micellar electrokinetic capillary chromatography  

Microsoft Academic Search

A method for quantitative analysis of thuringiensin is established using micellar electrokinetic capillary chromatography (MEKC). Tryptophan was used as an internal standard. The running buffer contained phosphate–borate (20 mM) and sodium dodecyl sulfate (100 mM) with 10% acetonitrile. Electrophoresis was conducted under a voltage of 15 kV for 20 min. The peak area ratio of thuringiensin to tryptophan was calculated

Cheng-Ming Liu; Yew-Min Tzeng

1998-01-01

112

Multipoint Quantitative-Trait Linkage Analysis in General Pedigrees  

Microsoft Academic Search

Summary Multipoint linkage analysis of quantitative-trait loci (QTLs) has previously been restricted to sibships and small pedigrees. In this article, we show how variance- component linkage methods can be used in pedigrees of arbitrary size and complexity, and we develop a general framework for multipoint identity-by-descent (IBD) probability calculations. We extend the sib-pair multi- point mapping approach of Fulker et

Laura Almasy; John Blangero

1998-01-01

113

Adaptive edge localisation approach for quantitative coronary analysis  

Microsoft Academic Search

Lack of reliability, user dissatisfaction and errors in determining coronary vessel wall characteristics are challenging issues\\u000a in quantitative coronary analysis (QCA). A new approach is proposed for QCA that tackles these issues. The proposed approach\\u000a extracts the coronary vessel edges by applying dynamic programming techniques that use human-based decision criteria, adaptive\\u000a edge detection and feature-based cost minimisation. This approach uses

A. S. Al-Fahoum

2003-01-01

114

Quantitative coronary analysis in the Nordic Bifurcation studies  

Microsoft Academic Search

Quantitative coronary analysis (QCA) of bifurcation lesions in the Nordic Bifurcation studies was performed using software\\u000a dedicated to bifurcating vessels. By now, pre-PCI, post-PCI and 8-month follow-up angiograms of 957 patients have been analyzed\\u000a in the first three Nordic Bifurcation studies. Large scale clinical studies with specific areas of interest require QCA software\\u000a with high intra- and inter observer reproducibility,

Niels R. HolmHelle HøjdahlJens; Helle Højdahl; Jens F. Lassen; Leif Thuesen; Michael Maeng

2011-01-01

115

Automated Epileptic Seizure Type Classification through Quantitative Movement Analysis  

Microsoft Academic Search

\\u000a In this paper we present the evolution of a quantitative movement analysis methodology for epileptic seizures. With this improved\\u000a method we analyzed 20 seizure video sequences, 10 classified as automotor and 10 as hypermotor, from 17 different patients.\\u000a The results obtained show we could classify all (100%) of the hypermotor seizures solely based on a quantified movement parameter\\u000a - called

J. P. Silva Cunha; C. Vollmar; J. M. Fernandes; S. Noachtar

116

Quantitative NMR Analysis of Partially Substituted Biodiesel Glycerols  

SciTech Connect

Phosphitylation of hydroxyl groups in biodiesel samples with 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane followed by 31P-NMR analysis provides a rapid quantitative analytical technique for the determination of substitution patterns on partially esterified glycerols. The unique 31P-NMR chemical shift data was established with a series mono and di-substituted fatty acid esters of glycerol and then utilized to characterize an industrial sample of partially processed biodiesel.

Nagy, M.; Alleman, T. L.; Dyer, T.; Ragauskas, A. J.

2009-01-01

117

Quantitative analysis of human immunoregulatory cytokines by electrochemiluminescence method  

Microsoft Academic Search

Quantitative analysis of human immunoregulatory cytokines in physiological media and cell cultures plays an important role in fundamental and clinical research. Here we describe the quantification of interleukin (IL)-2, IL-4, IL-10 and interferon-? (IFN-?) in human serum and peripheral blood mononuclear cell (PBMC)-conditioned medium by electrochemiluminescence method (ECL). We demonstrate that this approach allows to detect cytokine concentration from 1

Sergey V. Sennikov; Sergey V. Krysov; Tatiana V. Injelevskaya; Alexandr N. Silkov; Lyubov V. Grishina; Vladimir A. Kozlov

2003-01-01

118

An Automated X-Ray Gauge for Nondestructive Quantitative Analysis  

Microsoft Academic Search

An x-ray gauging system is described for nondestructive quantitative analysis. The automated device utilizes the transmission of low-energy x-rays through a material in order to measure the areal density of the material. Under some conditions, one material may be examined in the presence of another. Using digital rather than analog conversion techniques, measurement precision of 0.1% and accuracy near 0.5%

William D. Drotning

1988-01-01

119

Probabilistic Clustering and Quantitative Analysis of White Matter Fiber Tracts  

Microsoft Academic Search

A novel framework for joint clustering and point-by-point mapping of white matter fiber pathways is presented. Accurate clus- tering of the trajectories into fiber bundles requires point correspon- dence along the fiber pathways determined. This knowledge is also crucial for any tract-oriented quantitative analysis. We employ an expectation- maximization (EM) algorithm to cluster the trajectories in a Gamma mixture model

Mahnaz Maddah; William M. Wells III; Simon K. Warfield; Carl-fredrik Westin; W. Eric L. Grimson

2007-01-01

120

Quantitation of glycerophosphorylcholine by flow injection analysis using immobilized enzymes.  

PubMed

A method for quantitating glycerophosphorylcholine by flow injection analysis is reported in the present paper. Glycerophosphorylcholine phosphodiesterase and choline oxidase, immobilized on controlled porosity glass beads, are packed in a small reactor inserted in a flow injection manifold. When samples containing glycerophosphorylcholine are injected, glycerophosphorylcholine is hydrolyzed into choline and sn-glycerol-3-phosphate. The free choline produced in this reaction is oxidized to betain and hydrogen peroxide. Hydrogen peroxide is detected amperometrically. Quantitation of glycerophosphorylcholine in samples containing choline and phosphorylcholine is obtained inserting ahead of the reactor a small column packed with a mixed bed ion exchange resin. The time needed for each determination does not exceed one minute. The present method, applied to quantitate glycerophosphorylcholine in samples of seminal plasma, gave results comparable with those obtained using the standard enzymatic-spectrophotometric procedure. An alternative procedure, making use of co-immobilized glycerophosphorylcholine phosphodiesterase and glycerol-3-phosphate oxidase for quantitating glycerophosphorylcholine, glycerophosphorylethanolamine and glycerophosphorylserine is also described. PMID:8905629

Mancini, A; Del Rosso, F; Roberti, R; Caligiana, P; Vecchini, A; Binaglia, L

1996-09-20

121

Mini-Column Ion-Exchange Separation and Atomic Absorption Quantitation of Nickel, Cobalt, and Iron: An Undergraduate Quantitative Analysis Experiment.  

ERIC Educational Resources Information Center

|Presents an undergraduate quantitative analysis experiment, describing an atomic absorption quantitation scheme that is fast, sensitive and comparatively simple relative to other titration experiments. (CS)|

Anderson, James L.; And Others

1980-01-01

122

Mini-Column Ion-Exchange Separation and Atomic Absorption Quantitation of Nickel, Cobalt, and Iron: An Undergraduate Quantitative Analysis Experiment.  

ERIC Educational Resources Information Center

Presents an undergraduate quantitative analysis experiment, describing an atomic absorption quantitation scheme that is fast, sensitive and comparatively simple relative to other titration experiments. (CS)

Anderson, James L.; And Others

1980-01-01

123

Quantitative Epistasis Analysis and Pathway Inference from Genetic Interaction Data  

PubMed Central

Inferring regulatory and metabolic network models from quantitative genetic interaction data remains a major challenge in systems biology. Here, we present a novel quantitative model for interpreting epistasis within pathways responding to an external signal. The model provides the basis of an experimental method to determine the architecture of such pathways, and establishes a new set of rules to infer the order of genes within them. The method also allows the extraction of quantitative parameters enabling a new level of information to be added to genetic network models. It is applicable to any system where the impact of combinatorial loss-of-function mutations can be quantified with sufficient accuracy. We test the method by conducting a systematic analysis of a thoroughly characterized eukaryotic gene network, the galactose utilization pathway in Saccharomyces cerevisiae. For this purpose, we quantify the effects of single and double gene deletions on two phenotypic traits, fitness and reporter gene expression. We show that applying our method to fitness traits reveals the order of metabolic enzymes and the effects of accumulating metabolic intermediates. Conversely, the analysis of expression traits reveals the order of transcriptional regulatory genes, secondary regulatory signals and their relative strength. Strikingly, when the analyses of the two traits are combined, the method correctly infers ?80% of the known relationships without any false positives.

Phenix, Hilary; Morin, Katy; Batenchuk, Cory; Parker, Jacob; Abedi, Vida; Yang, Liu; Tepliakova, Lioudmila; Perkins, Theodore J.; Kaern, Mads

2011-01-01

124

First report of aphantoxins in China--waterblooms of toxigenic Aphanizomenon flos-aquae in Lake Dianchi.  

PubMed

The oligohaline cyanobacterium Aphanizomenon flos-aquae (L.) Ralfs (A. flos-aquae) has been reported in several countries to produce paralytic shellfish poisons (PSPs) or protracted toxic effects. In the past years, A. flos-aquae blooms have occurred annually in the eutrophic Lake Dianchi (300 km(2) in area, located in southwestern China). Material from natural blooms dominated by A. flos-aquae was collected and lyophilized. Acute toxicity testing was performed by mouse bioassay using extracts from the lyophilized material. Clear symptoms of PSPs intoxications were observed. To confirm the production of PSPs, a strain of A. flos-aquae (DC-1) was isolated and maintained in culture. Histopathological effects were studied by examining the organ damages using transmission electron microscopy (TEM). Slight hepatocytic damage with swollen mitochondria was found. The ultrastructural pulmonary lesions were characterized by distortied nuclei and indenting of karyotheca, together with degeneration and tumefaction of mitochondria and endoplasmic reticulum. Control animals injected with acetic acid did not exhibit histopathological damage in any organ. Toxic effects of cultured algal cells on enzymatic systems in the mouse were studied using sublethal doses of extracts. Significant glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) increases, together with decrease of the glutathione (GSH) level, were measured. These results indicated a potential role of PSPs intoxicating and metabolizing in the test animals. HPLC-FLD and LC/MS analysis of extracts from cultured material demonstrated the PSP toxins produced by A. flos-aquae bloom. To the best of our knowledge, this is the first study reporting chemically and toxicologically confirmed PSP toxins related to A. flos-aquae in China. PMID:16289338

Liu, Yongmei; Chen, Wei; Li, Dunhai; Shen, Yinwu; Li, Genbao; Liu, Yongding

2005-11-10

125

Quantitative analysis of endocytosis with cytoplasmic pHluorin chimeras  

PubMed Central

The pH-sensitive GFP variant pHluorin is typically fused to the extracellular domain of transmembrane proteins to monitor endocytosis. Here we have turned pHluorin inside-out, and demonstrate that cytoplasmic fusions of pHluorin are effective quantitative reporters for endocytosis and MVB sorting. In yeast in particular, fusion of GFP and its variants on the extracellular side of transmembrane proteins can result in perturbed trafficking. In contrast, cytoplasmic fusions are well tolerated, allowing for the quantitative assessment of trafficking of virtually any transmembrane protein. Quenching of degradation-resistant pHluorin in the acidic vacuole permits quantification of extra-vacuolar cargo proteins at steady-state levels and is compatible with kinetic analysis of endocytosis in live cells.

Prosser, Derek C.; Whitworth, Karen; Wendland, Beverly

2010-01-01

126

Label-Free Technologies for Quantitative Multiparameter Biological Analysis  

PubMed Central

In the post-genomic era, information is king and information-rich technologies are critically important drivers in both fundamental biology and medicine. It is now known that single-parameter measurements provide only limited detail and that quantitation of multiple biomolecular signatures can more fully illuminate complex biological function. Label-free technologies have recently attracted significant interest for sensitive and quantitative multiparameter analysis of biological systems. There are several different classes of label-free sensors that are currently being developed both in academia and in industry. In this critical review, we highlight, compare, and contrast some of the more promising approaches. We will describe the fundamental principles of these different methodologies and discuss advantages and disadvantages that might potentially help one in selecting the appropriate technology for a given bioanalytical application.

Qavi, Abraham J.; Washburn, Adam L.; Byeon, Ji-Yeon; Bailey, Ryan C.

2009-01-01

127

Quantitative analysis of nonequilibrium spin injection into molecular tunnel junctions.  

PubMed

We report quantitative analysis of nonequilibrium spin injection from Ni contacts to the octanethiol molecular spintronic system. Our calculation is based on carrying out density functional theory within the Keldysh nonequilibrium Green's function formalism. The first principles results allow us to establish a clear physical picture on how spins are injected from the Ni contacts through the Ni-molecule linkage to the molecule, why tunnel magnetoresistance is rapidly reduced by the applied bias in an asymmetric manner, and to what extent ab initio transport theory can make quantitative comparisons to the corresponding experimental data. We found that extremely careful sampling of the two-dimensional Brillouin zone of the Ni surface is crucial for accurate results. PMID:18352408

Ning, Zhanyu; Zhu, Yu; Wang, Jian; Guo, Hong

2008-02-06

128

Risk Assessment of Microcystin in Dietary Aphanizomenon flos-aquae  

Microsoft Academic Search

Aphanizomenon flos-aquae, a cyanobacterium that is marketed as a health food supplement, is harvested from natural blooms in Klamath Lake (Oregon) that are occasionally contaminated by Microcystis spp. Regulatory agencies in several countries are developing regulations to control the amount of microcystin in drinking water and other products, including products produced from A. flos-aquae. Regulation of microcystin (MC), a toxin

David J. Schaeffer; Phyllis B. Malpas; Larry L. Barton

1999-01-01

129

Aqua MODIS 8-year on-orbit operation and calibration  

Microsoft Academic Search

Launched in May 2002, the NASA EOS Aqua MODIS has successfully operated for more than 8 years. Observations from Aqua MODIS and its predecessor, Terra MODIS, have generated an unprecedented amount of data products and made significant contributions to studies of changes in the Earth's system of land, oceans, and atmosphere. MODIS collects data in 36 spectral bands: 20 reflective

Xiaoxiong Xiong; Amit Angal; Sriharsha Madhavan; Taeyoung Choi; Jennifer Dodd; Xu Geng; Zhipeng Wang; Gary Toller; William Barnes

2010-01-01

130

Quantitative Analysis of Aberrant p16 Methylation Using Real-Time Quantitative Methylation-specific Polymerase Chain Reaction1  

Microsoft Academic Search

We have developed a quantitative method for methylation analysis of the p16 gene based on real-time methylation-specific PCR (MSP). Real- time MSP is sensitive enough to detect down to 10 genome equivalents of the methylated p16 sequence. Application of real-time MSP to DNA from tumor-derived cell lines revealed complete concordance with conventional MSP analysis. Quantitative data generated by real-time MSP

Y. M. Dennis Lo; Ivy H. N. Wong; Jun Zhang; Mark S. C. Tein; Margaret H. L. Ng; N. Magnus Hjelm

1999-01-01

131

Quantitative Analysis of Liver Golgi Proteome in the Cell Cycle  

PubMed Central

During mitosis, the Golgi membranes in mammalian cells undergo a continuous disassembly process and generate mitotic fragments that are distributed into the daughter cells and reassembled into new Golgi after mitosis. This disassembly and reassembly process is critical for Golgi biogenesis during cell division, but the underlying molecular mechanism is poorly understood. In this study, we have recapitulated this process using an in vitro assay and analyzed the proteins that are associated with interphase and mitotic Golgi membranes using quantitative proteomics that combines the isobaric tags for relative and absolute quantification approach with OFFGEL isoelectric focusing separation and LC-MALDI-MS/MS. A total of 1,193 Golgi-associated proteins were identified and quantified. These included broad functional categories: Golgi structural proteins, Golgi resident enzymes, SNAREs, Rab GTPases, and secretory and cytoskeletal proteins. More importantly, the combination of the quantitative proteomic approach with Western blot analysis allowed us to unveil 86 proteins with significant changes in abundance under the mitotic condition compared to the interphase condition. Altogether, this systematic quantitative proteomic study revealed candidate proteins of the molecular machinery that controls the Golgi disassembly and reassembly processes in the cell cycle.

Chen, Xuequn; Andrews, Philip C.; Wang, Yanzhuang

2013-01-01

132

Quantitative analysis of liver Golgi proteome in the cell cycle.  

PubMed

During mitosis, the Golgi membranes in mammalian cells undergo a continuous disassembly process and generate mitotic fragments that are distributed into the daughter cells and reassembled into new Golgi after mitosis. This disassembly and reassembly process is critical for Golgi biogenesis during cell division, but the underlying molecular mechanism is poorly understood. In this study, we have recapitulated this process using an in vitro assay and analyzed the proteins that are associated with interphase and mitotic Golgi membranes using quantitative proteomics that combines the isobaric tags for relative and absolute quantification approach with OFFGEL isoelectric focusing separation and LC-MALDI-MS/MS. A total of 1,193 Golgi-associated proteins were identified and quantified. These included broad functional categories: Golgi structural proteins, Golgi resident enzymes, SNAREs, Rab GTPases, and secretory and cytoskeletal proteins. More importantly, the combination of the quantitative proteomic approach with Western blot analysis allowed us to unveil 86 proteins with significant changes in abundance under the mitotic condition compared to the interphase condition. Altogether, this systematic quantitative proteomic study revealed candidate proteins of the molecular machinery that controls the Golgi disassembly and reassembly processes in the cell cycle. PMID:22903713

Chen, Xuequn; Andrews, Philip C; Wang, Yanzhuang

2012-01-01

133

Teaching neuroinformatics with an emphasis on quantitative locus analysis.  

PubMed

Although powerful bioinformatics tools are available for free on the web and are used by neuroscience professionals on a daily basis, neuroscience students are largely ignorant of them. This Neuroinformatics module weaves together several bioinformatics tools to make a comprehensive unit. This unit encompasses quantifying a phenotype through a Quantitative Trait Locus (QTL) analysis, which links phenotype to loci on chromosomes that likely had an impact on the phenotype. Students then are able to sift through a list of genes in the region(s) of the chromosome identified by the QTL analysis and find a candidate gene that has relatively high expression in the brain region of interest. Once such a candidate gene is identified, students can find out more information about the gene, including the cells/layers in which it is expressed, the sequence of the gene, and an article about the gene. All of the resources employed are available at no cost via the internet. Didactic elements of this instructional module include genetics, neuroanatomy, Quantitative Trait Locus analysis, molecular techniques in neuroscience, and statistics-including multiple regression, ANOVA, and a bootstrap technique. This module was presented at the Faculty for Undergraduate Neuroscience (FUN) 2011 Workshop at Pomona College and can be accessed at http://mdcune.psych.ucla.edu/modules/bioinformatics. PMID:23493834

Grisham, William; Korey, Christopher A; Schottler, Natalie A; McCauley, Lisa Beck; Beatty, Jackson

2012-10-15

134

The Use of Automated Quantitative Analysis to Evaluate Epithelial-to-Mesenchymal Transition Associated Proteins in Clear Cell Renal Cell Carcinoma  

PubMed Central

Background Epithelial-to-mesenchymal transition (EMT) has recently been implicated in the initiation and progression of renal cell carcinoma (RCC). Some mRNA gene expression studies have suggested a link between the EMT phenotype and poorer clinical outcome from RCC. This study evaluated expression of EMT-associated proteins in RCC using in situ automated quantitative analysis immunofluorescence (AQUA) and compared expression levels with clinical outcome. Methods/Principal Findings Unsupervised hierarchical cluster analysis of pre-existing RCC gene expression array data (GSE16449) from 36 patients revealed the presence of an EMT transcriptional signature in RCC [E-cadherin high/SLUG low/SNAIL low]. As automated immunofluorescence technology is dependent on accurate definition of the tumour cells in which measurements take place is critical, extensive optimisation was carried out resulting in a novel pan-cadherin based tumour mask that distinguishes renal cancer cells from stromal components. 61 patients with ccRCC and clinical follow-up were subsequently assessed for expression of EMT-associated proteins (WT1, SNAIL, SLUG, E-cadherin and phospho-?-catenin) on tissue microarrays. Using Kaplan-Meier analysis both SLUG (p?=?0.029) and SNAIL (p?=?0.024) (log rank Mantel-Cox) were significantly associated with prolonged progression free survival (PFS). Using Cox regression univariate and multivariate analysis none of the biomarkers were significantly correlated with outcome. 14 of the 61 patients expressed the gene expression analysis predicted EMT-protein signature [E-cadherin high/SLUG low/SNAIL low], which was not found to be associated to PFS when measured at the protein level. A combination of high expression of SNAIL and low stage was able to stratify patients with greater significance (p?=?0.001) then either variable alone (high SNAIL p?=?0.024, low stage p?=?0.029). Conclusions AQUA has been shown to have the potential to identify EMT related protein targets in RCC allowing for stratification of patients into high and low risk groups, as well the ability to assess the association of reputed EMT signatures to progression of the disease.

O'Mahony, Fiach C.; Faratian, Dana; Varley, James; Nanda, Jyoti; Theodoulou, Marianna; Riddick, Antony C. P.; Harrison, David J.; Stewart, Grant D.

2012-01-01

135

AQUA AMSR-E Sea Surface Temperature  

NASA Astrophysics Data System (ADS)

NASA's AQUA satellite carries the JAXA's Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E). The AQUA satellite was launched in May 2002 into a polar, sun-synchronous orbit at an altitude of 705 km, with a LECT of 1:30 AM/PM. AMSR-E has 12 channels corresponding to 6 frequencies; all except 23.8 GHz measure both vertical and horizontal polarizations. Geophysical retrievals of SST, wind speed, water vapor, cloud liquid water, and rain rates are calculated using a multi-stage linear regression algorithm derived through comprehensive radiative transfer model simulations. SST retrievals are prevented by rain, sun glint, near land emissions, and radio frequency interference due to geostationary satellite broadcasts. Since only a small number of retrievals are unsuccessful, almost complete global coverage is available daily. At high latitudes, where cloud cover regularly prevents infrared observations of SSTs, the microwave observations of SST provide a significant improvement to measurement capabilities. Validation of the datasets through comparison to the global drifting buoy networks yields mean biases of -0.02 K and standard deviations of 0.50 K. AMSR-E SSTs have been widely used for numerical weather prediction, ocean modeling, fisheries, and oceanographic research.

Gentemann, C. L.

2011-12-01

136

Enhanced efficiency of quantitative trait loci mapping analysis based on multivariate complexes of quantitative traits.  

PubMed Central

An approach to increase the efficiency of mapping quantitative trait loci (QTL) was proposed earlier by the authors on the basis of bivariate analysis of correlated traits. The power of QTL detection using the log-likelihood ratio (LOD scores) grows proportionally to the broad sense heritability. We found that this relationship holds also for correlated traits, so that an increased bivariate heritability implicates a higher LOD score, higher detection power, and better mapping resolution. However, the increased number of parameters to be estimated complicates the application of this approach when a large number of traits are considered simultaneously. Here we present a multivariate generalization of our previous two-trait QTL analysis. The proposed multivariate analogue of QTL contribution to the broad-sense heritability based on interval-specific calculation of eigenvalues and eigenvectors of the residual covariance matrix allows prediction of the expected QTL detection power and mapping resolution for any subset of the initial multivariate trait complex. Permutation technique allows chromosome-wise testing of significance for the whole trait complex and the significance of the contribution of individual traits owing to: (a) their correlation with other traits, (b) dependence on the chromosome in question, and (c) both a and b. An example of application of the proposed method on a real data set of 11 traits from an experiment performed on an F(2)/F(3) mapping population of tetraploid wheat (Triticum durum x T. dicoccoides) is provided.

Korol, A B; Ronin, Y I; Itskovich, A M; Peng, J; Nevo, E

2001-01-01

137

Qualitative and quantitative analysis of wood samples by Fourier transform infrared spectroscopy and multivariate analysis  

Microsoft Academic Search

Fourier transform infrared (FTIR) spectroscopy, in combination with multivariate analysis, enable the analysis of wood samples without time-consuming sample preparation. The aim of our work was to analysis the wood samples qualitatively and quantitatively by FTIR spectroscopy. A Van Soest method to determine the lignin, cellulose and hemicellulose content, was used as reference method. Multivariate calibration was performed based on

Huilun Chen; Carlo Ferrari; Marco Angiuli; Jun Yao; Costantino Raspi; Emilia Bramanti

2010-01-01

138

Multivariate calibration applied to the quantitative analysis of infrared spectra  

SciTech Connect

Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of phosphosilicate glass thin films on silicon wafers. Comparisons of the relative prediction abilities of four different multivariate calibration methods are given based on Monte Carlo simulations of spectral calibration and prediction data. The success of multivariate spectral calibrations is demonstrated for several quantitative infrared studies. The infrared absorption and emission spectra of thin-film dielectrics used in the manufacture of microelectronic devices demonstrate rapid, nondestructive at-line and in-situ analyses using PLS calibrations. Finally, the application of multivariate spectral calibrations to reagentless analysis of blood is presented. We have found that the determination of glucose in whole blood taken from diabetics can be precisely monitored from the PLS calibration of either mind- or near-infrared spectra of the blood. Progress toward the non-invasive determination of glucose levels in diabetics is an ultimate goal of this research. 13 refs., 4 figs.

Haaland, D.M.

1991-01-01

139

Quantitative analysis of volume images: electron microscopic tomography of HIV  

NASA Astrophysics Data System (ADS)

Three-dimensional objects should be represented by 3D images. So far, most of the evaluation of images of 3D objects have been done visually, either by looking at slices through the volumes or by looking at 3D graphic representations of the data. In many applications a more quantitative evaluation would be valuable. Our application is the analysis of volume images of the causative agent of the acquired immune deficiency syndrome (AIDS), namely human immunodeficiency virus (HIV), produced by electron microscopic tomography (EMT). A structural analysis of the virus is of importance. The representation of some of the interesting structural features will depend on the orientation and the position of the object relative to the digitization grid. We describe a method of defining orientation and position of objects based on the moment of inertia of the objects in the volume image. In addition to a direct quantification of the 3D object a quantitative description of the convex deficiency may provide valuable information about the geometrical properties. The convex deficiency is the volume object subtracted from its convex hull. We describe an algorithm for creating an enclosing polyhedron approximating the convex hull of an arbitrarily shaped object.

Nystrom, Ingela; Bengtsson, Ewert W.; Nordin, Bo G.; Borgefors, Gunilla

1994-05-01

140

Quantitative analysis of live cells using digital holographic microscopy  

NASA Astrophysics Data System (ADS)

During the life time of a cell, it goes through changes to the plasma membrane as well as its internal structures especially distinctive during processes like cell division and death. Different types of microscope are used to fulfill the observation of the cell's variation. In our experiment, Vero cells have been investigated by using phase contrast microscopy and digital holographic microscopy (DHM). A comparison of the images obtained for cell division is presented here. The conventional phase contrast microscope provided a good imaging method in the real time analysis of cell division. The off-axis digital hologram recorded by the DHM system can be reconstructed to obtain both the intensity image and phase contrast image of the test object. These can be used for live cell imaging to provide multiple results from a single equipment setup. The DHM system, besides being a qualitative tool, is able to provide quantitative results and 3D images of the cell division process. The ability of DHM to provide quantitative analysis makes it an ideal tool for life science applications.

Lewis, Tan Rongwei; Qu, Weijuan; Chee, Oi Choo; Singh, Vijay Raj; Asundi, Anand

2009-12-01

141

Ecotoxicological impact of sunlight assisted photoreduction of hexavalent chromium present in wastewater with zinc oxide nanoparticles on common Anabaena flos-aquae.  

PubMed

Hexavalent chromium is more toxic and carcinogenic compared to its trivalent counterpart. Hexavalent chromium can be photocatalytically reduced to trivalent one using zinc oxide semiconductor and solar or UV radiation as light source. But an important ecological aspect is whether the net toxicity decreases after the photocatalytic process. In the present work, we have selected Anabaena flos-aquae as the model organism and examined whether the net toxicity to which it has been exposed in water decreases after photocatalytic reduction of hexavalent chromium using ZnO semiconductor as photocatalyst. We have studied the cumulative toxicities of both chromium (before and after treatment) and ZnO (both nano and micro) separately and as a suspension of ZnO in chromium. Quantitative cell surface roughness analysis was conducted using AFM to confirm the changes in cell surface properties. PMID:23025895

Nandi, Isita; Mitra, Pallavi; Banerjee, Prantik; Chakrabarti, Anirban; Ghosh, Mahua; Chakrabarti, Sampa

2012-09-29

142

Quantitative movement analysis differentiates focal seizures characterized by automatisms.  

PubMed

The analysis of epileptic seizures is typically performed by visual inspection, limited by interrater variation. Our aim was to differentiate seizures characterized by automatisms with an objective, quantitative movement analysis. In part 1 of this study we found parameters (extent and speed of movement of the wrist and trunk) separating seizures with predominant proximal (hyperkinetic, n=10) and distal (automotor, n=10) limb automatisms (P<0.002). For each movement parameter we used the lowest value recorded for a hyperkinetic seizure in part 1 as the cutoff parameter in part 2 on a consecutive sample of 100 motor seizures. As in part 1, the difference between hyperkinetic and non-hyperkinetic seizures was highly significant (<0.001). When all movement parameters were above the threshold, a hyperkinetic seizure was identified with a probability of 80.8%, but the probability for a non-hyperkinetic seizure to have all parameters above the threshold was only 0.02%. PMID:21458386

Rémi, Jan; Cunha, João P Silva; Vollmar, Christian; Topçuo?lu, Özgür Bilgin; Meier, Alexander; Ulowetz, Steffen; Beleza, Pedro; Noachtar, Soheyl

2011-03-31

143

RNA sequencing and quantitation using the Helicos Genetic Analysis System.  

PubMed

The recent transition in gene expression analysis technology to ultra high-throughput cDNA sequencing provides a means for higher quantitation sensitivity across a wider dynamic range than previously possible. Sensitivity of detection is mostly a function of the sheer number of sequence reads generated. Typically, RNA is converted to cDNA using random hexamers and the cDNA is subsequently sequenced (RNA-Seq). With this approach, higher read numbers are generated for long transcripts as compared to short ones. This length bias necessitates the generation of very high read numbers to achieve sensitive quantitation of short, low-expressed genes. To eliminate this length bias, we have developed an ultra high-throughput sequencing approach where only a single read is generated for each transcript molecule (single-molecule sequencing Digital Gene Expression (smsDGE)). So, for example, equivalent quantitation accuracy of the yeast transcriptome can be achieved by smsDGE using only 25% of the reads that would be required using RNA-Seq. For sample preparation, RNA is first reverse-transcribed into single-stranded cDNA using oligo-dT as a primer. A poly-A tail is then added to the 3' ends of cDNA to facilitate the hybridization of the sample to the Helicos(®) single-molecule sequencing Flow-Cell to which a poly dT oligo serves as the substrate for subsequent sequencing by synthesis. No PCR, sample-size selection, or ligation steps are required, thus avoiding possible biases that may be introduced by such manipulations. Each tailed cDNA sample is injected into one of 50 flow-cell channels and sequenced on the Helicos(®) Genetic Analysis System. Thus, 50 samples are sequenced simultaneously generating 10-20 million sequence reads on average for each sample channel. The sequence reads can then be aligned to the reference of choice such as the transcriptome, for quantitation of known transcripts, or the genome for novel transcript discovery. This chapter provides a summary of the methods required for smsDGE. PMID:21431761

Raz, Tal; Causey, Marie; Jones, Daniel R; Kieu, Alix; Letovsky, Stan; Lipson, Doron; Thayer, Edward; Thompson, John F; Milos, Patrice M

2011-01-01

144

Is the new AquaTrainer® snorkel valid for VO2 assessment in swimming?  

PubMed

The Cosmed AquaTrainer® snorkel, in connection with the K4b2 analyzer, is the most recent instrument used for real time gas analysis during swimming. This study aimed to test if a new AquaTrainer® snorkel with 2 (SV2) or 4 (SV4) valves is comparable to a standard face mask (Mask) being valid for real time gas analysis under controlled laboratory and swimming pool conditions. 9 swimmers performed 2 swimming and 3 cycling tests at 3 different workloads on separate days. Tests were performed in random order, at constant exercise load with direct turbine temperature measurements, breathing with Mask, SV4 and SV2 while cycling, and with SV2 and SV4 while swimming. A high agreement was obtained using Passing - Bablok regression analysis in oxygen consumption, carbon dioxide production, tidal volumes, pulmonary ventilation, expiratory fraction of oxygen and carbon dioxide, and heart rate comparing different conditions in swimming and cycling. Proportional and fixed differences were always rejected (95% CI always contained the value 1 for the slope and the 0 for the intercept). In conclusion, the new SV2 AquaTrainer® snorkel, can be considered a valid device for gas analysis, being comparable to the Mask and the SV4 in cycling, and to the SV4 in swimming. PMID:23041962

Baldari, C; Fernandes, R J; Meucci, M; Ribeiro, J; Vilas-Boas, J P; Guidetti, L

2012-10-05

145

Cell cycle studies based upon quantitative image analysis.  

PubMed

When cell cycle studies are performed following cell cycle synchronization, it is possible that critical properties of an actively cycling cell will be overlooked. For this reason past studies have not revealed critical aspects of cell cycle control; such as how a cell determines when to exit the cell cycle, or how rapidly it should cycle. To address these challenging questions we have developed a procedure to quantitate fluorescent stains in a monolayer culture, where nuclear fluorescence and cell cycle history can be assessed with accuracy on a cell by cell basis. The cell cycle position of each cell can be determined by analyzing DNA and BrdU levels. The behavior of cells in a given cell cycle position can then be studied by quantitating up to two other stained markers. When the microinjection of siRNA, neutralizing antibodies, and expression plasmids are coupled with quantitative image analysis, these cell cycle studies can be conducted following alterations in the expression levels of selected cellular targets. With these techniques we have discovered critical aspects of cell cycle control; including how cyclin D1 levels vary through the cell cycle, the molecular mechanisms governing these changes, and the biological implications of changes in cyclin D1 concentration in various cell cycle stages. Our studies with cyclin D1, coupled with similar studies of p27Kip1, form the basis of an entirely new model of cell cycle control proposed here. This model explains how cell cycle progression is terminated, and how the length of the cell cycle is regulated. PMID:18163464

Stacey, Dennis W; Hitomi, Masahiro

2008-04-01

146

AquaEnv : An Aqua tic Acid–Base Modelling Env ironment in R  

Microsoft Academic Search

AquaEnv\\u000a is an integrated software package for aquatic chemical model generation focused on ocean acidification and antropogenic CO2 uptake. However, the package is not restricted to the carbon cycle or the oceans: it calculates, converts, and visualizes\\u000a information necessary to describe pH, related CO2 air–water exchange, as well as aquatic acid–base chemistry in general for marine, estuarine or freshwater systems.

Andreas F. HofmannKarline; Karline Soetaert; Jack J. Middelburg; Filip J. R. Meysman

2010-01-01

147

Sampling issues in quantitative analysis of dendritic spines morphology  

PubMed Central

Background Quantitative analysis of changes in dendritic spine morphology has become an interesting issue in contemporary neuroscience. However, the diversity in dendritic spine population might seriously influence the result of measurements in which their morphology is studied. The detection of differences in spine morphology between control and test group is often compromised by the number of dendritic spines taken for analysis. In order to estimate the impact of dendritic spine diversity we performed Monte Carlo simulations examining various experimental setups and statistical approaches. The confocal images of dendritic spines from hippocampal dissociated cultures have been used to create a set of variables exploited as the simulation resources. Results The tabulated results of simulations given in this article, provide the number of dendritic spines required for the detection of hidden morphological differences between control and test groups in terms of spine head-width, length and area. It turns out that this is the head-width among these three variables, where the changes are most easily detected. Simulation of changes occurring in a subpopulation of spines reveal the strong dependence of detectability on the statistical approach applied. The analysis based on comparison of percentage of spines in subclasses is less sensitive than the direct comparison of relevant variables describing spines morphology. Conclusions We evaluated the sampling aspect and effect of systematic morphological variation on detecting the differences in spine morphology. The results provided here may serve as a guideline in selecting the number of samples to be studied in a planned experiment. Our simulations might be a step towards the development of a standardized method of quantitative comparison of dendritic spines morphology, in which different sources of errors are considered.

2012-01-01

148

Functional linear models for association analysis of quantitative traits.  

PubMed

Functional linear models are developed in this paper for testing associations between quantitative traits and genetic variants, which can be rare variants or common variants or the combination of the two. By treating multiple genetic variants of an individual in a human population as a realization of a stochastic process, the genome of an individual in a chromosome region is a continuum of sequence data rather than discrete observations. The genome of an individual is viewed as a stochastic function that contains both linkage and linkage disequilibrium (LD) information of the genetic markers. By using techniques of functional data analysis, both fixed and mixed effect functional linear models are built to test the association between quantitative traits and genetic variants adjusting for covariates. After extensive simulation analysis, it is shown that the F-distributed tests of the proposed fixed effect functional linear models have higher power than that of sequence kernel association test (SKAT) and its optimal unified test (SKAT-O) for three scenarios in most cases: (1) the causal variants are all rare, (2) the causal variants are both rare and common, and (3) the causal variants are common. The superior performance of the fixed effect functional linear models is most likely due to its optimal utilization of both genetic linkage and LD information of multiple genetic variants in a genome and similarity among different individuals, while SKAT and SKAT-O only model the similarities and pairwise LD but do not model linkage and higher order LD information sufficiently. In addition, the proposed fixed effect models generate accurate type I error rates in simulation studies. We also show that the functional kernel score tests of the proposed mixed effect functional linear models are preferable in candidate gene analysis and small sample problems. The methods are applied to analyze three biochemical traits in data from the Trinity Students Study. PMID:24130119

Fan, Ruzong; Wang, Yifan; Mills, James L; Wilson, Alexander F; Bailey-Wilson, Joan E; Xiong, Momiao

2013-11-01

149

Quantitative infrared analysis of borophosphosilicate films using multivariate statistical methods  

SciTech Connect

Infrared (IR) spectroscopy can serve as a rapid method for the quantitative analysis of borophosphosilicate glass (BPSG) films on Si wafers for the microelectronics industry. The advantages of using statistically designed calibration sets are emphasized. Classical least-squares (CLS), partial least-squares (PLS), and principal component regression (PCR) methods are all found to provide improved precision over traditional peak-height measurements. The quantitative results from spectral measurements taken in transmission mode at both 0/sup 0/ and 60/sup 0/ incident angles were also compared. PLS and PCR methods yielded results that were comparable within the sampling error, and each exhibited a better analysis precision than that obtained from the CLS analysis. Both PLS and PCR methods yielded the best results when applied to the original 60/sup 0/ incident angle data, which was not corrected for film thickness. PLS and PCR analyses each gave a standard error of prediction (SEP) for boron of approx. = 0.1 wt% and approx. = 0.2 wt % for phosphorus for a set of 44 calibration samples which spanned a range of concentrations from 1 to 5 wt % B and 2 to 6 wt % P. The PLS and PCR methods applied to the IR spectra were also capable of monitoring film thickness with a SEP of 14 nm for films that varied in thickness from 430 to 1000 nm. The importance of using these full-spectrum multivariate methods for outlier sample detection is presented, and the ability to extract qualitative spectral information from the CLS and PLS calibrations is demonstrated.

Haaland, D.M.

1988-06-01

150

Predictability Aspects of Global Aqua-planet Simulations with Explicit Convection  

Microsoft Academic Search

High-resolution global simulations over zonally symmetric aqua planets are examined using Fourier analysis in the zonal direction. We highlight the tropics, where the large-scale weather consists of convectively-coupled waves so that explicit convection is an especially topical novelty. Squared differences between pairs of runs grow from initially tiny values to saturation at twice the climatological variance. For wavelengths shorter than

Brian MAPES; Stefan TULICH; Tomoe NASUNO; Masaki SATOH

2008-01-01

151

Mueggelone, a novel inhibitor of fish development from the fresh water cyanobacterium Aphanizomenon flos-aquae.  

PubMed

A novel C18 lipid, containing a 10-membered lactone, mueggelone (1), was isolated from a field-collected sample of Aphanizomenon flos-aquae, together with the known compound lupenyl acetate (3). Both structures were secured using extensive spectroscopic analysis (1D and 2D NMR, MS, IR). Biological activity assessment of both compounds indicated them to have significant inhibitory effects on fish embryo larval development. PMID:9428164

Papendorf, O; König, G M; Wright, A D; Chorus, I; Oberemm, A

1997-12-01

152

Quantitative analysis of gene function in the Drosophila embryo.  

PubMed Central

The specific functions of gene products frequently depend on the developmental context in which they are expressed. Thus, studies on gene function will benefit from systems that allow for manipulation of gene expression within model systems where the developmental context is well defined. Here we describe a system that allows for genetically controlled overexpression of any gene of interest under normal physiological conditions in the early Drosophila embryo. This regulated expression is achieved through the use of Drosophila lines that express a maternal mRNA for the yeast transcription factor GAL4. Embryos derived from females that express GAL4 maternally activate GAL4-dependent UAS transgenes at uniform levels throughout the embryo during the blastoderm stage of embryogenesis. The expression levels can be quantitatively manipulated through the use of lines that have different levels of maternal GAL4 activity. Specific phenotypes are produced by expression of a number of different developmental regulators with this system, including genes that normally do not function during Drosophila embryogenesis. Analysis of the response to overexpression of runt provides evidence that this pair-rule segmentation gene has a direct role in repressing transcription of the segment-polarity gene engrailed. The maternal GAL4 system will have applications both for the measurement of gene activity in reverse genetic experiments as well as for the identification of genetic factors that have quantitative effects on gene function in vivo.

Tracey, W D; Ning, X; Klingler, M; Kramer, S G; Gergen, J P

2000-01-01

153

Quantitative analysis of incipient mineral loss in hard tissues  

NASA Astrophysics Data System (ADS)

A coupled diffuse-photon-density-wave and thermal-wave theoretical model was developed to describe the biothermophotonic phenomena in multi-layered hard tissue structures. Photothermal Radiometry was applied as a safe, non-destructive, and highly sensitive tool for the detection of early tooth enamel demineralization to test the theory. Extracted human tooth was treated sequentially with an artificial demineralization gel to simulate controlled mineral loss in the enamel. The experimental setup included a semiconductor laser (659 nm, 120 mW) as the source of the photothermal signal. Modulated laser light generated infrared blackbody radiation from teeth upon absorption and nonradiative energy conversion. The infrared flux emitted by the treated region of the tooth surface and sub-surface was monitored with an infrared detector, both before and after treatment. Frequency scans with a laser beam size of 3 mm were performed in order to guarantee one-dimensionality of the photothermal field. TMR images showed clear differences between sound and demineralized enamel, however this technique is destructive. Dental radiographs did not indicate any changes. The photothermal signal showed clear change even after 1 min of gel treatment. As a result of the fittings, thermal and optical properties of sound and demineralized enamel were obtained, which allowed for quantitative differentiation of healthy and non-healthy regions. In conclusion, the developed model was shown to be a promising tool for non-invasive quantitative analysis of early demineralization of hard tissues.

Matvienko, Anna; Mandelis, Andreas; Hellen, Adam; Jeon, Raymond; Abrams, Stephen; Amaechi, Bennett

2009-02-01

154

Quantitative analysis of multiple sclerosis: a feasibility study  

NASA Astrophysics Data System (ADS)

Multiple Sclerosis (MS) is an inflammatory and demyelinating disorder of the central nervous system with a presumed immune-mediated etiology. For treatment of MS, the measurements of white matter (WM), gray matter (GM), and cerebral spinal fluid (CSF) are often used in conjunction with clinical evaluation to provide a more objective measure of MS burden. In this paper, we apply a new unifying automatic mixture-based algorithm for segmentation of brain tissues to quantitatively analyze MS. The method takes into account the following effects that commonly appear in MR imaging: 1) The MR data is modeled as a stochastic process with an inherent inhomogeneity effect of smoothly varying intensity; 2) A new partial volume (PV) model is built in establishing the maximum a posterior (MAP) segmentation scheme; 3) Noise artifacts are minimized by a priori Markov random field (MRF) penalty indicating neighborhood correlation from tissue mixture. The volumes of brain tissues (WM, GM) and CSF are extracted from the mixture-based segmentation. Experimental results of feasibility studies on quantitative analysis of MS are presented.

Li, Lihong; Li, Xiang; Wei, Xinzhou; Sturm, Deborah; Lu, Hongbing; Liang, Zhengrong

2006-03-01

155

Qualitative and quantitative analysis of probabilistic and deterministic fiber tracking  

NASA Astrophysics Data System (ADS)

Fiber tracking (FT) and quantification algorithms are approximations of reality due to limited spatial resolution, model assumptions, user-defined parameter settings, and physical imaging artifacts resulting from diffusion sequences. Until now, correctness, plausibility, and reliability of both FT and quantification techniques have mainly been verified using histologic knowledge and software or hardware phantoms. Probabilistic FT approaches aim at visualizing the uncertainty present in the data by incorporating models of the acquisition process and noise. The uncertainty is assessed by tracking many possible paths originating from a single seed point, thereby taking the tensor uncertainty into account. Based on the tracked paths, maps of connectivity probabilities can be produced, which may be used to delineate risk structures for presurgical planning. In this paper, we explore the advantages and disadvantages of probabilistic approaches compared to deterministic algorithms and give both qualitative and quantitative comparisons based on clinical data. We focus on two important clinical applications, namely, on the reconstruction of fiber bundles within the proximity of tumors and on the quantitative analysis of diffusion parameters along fiber bundles. Our results show that probabilistic FT is superior and suitable for a better reconstruction at the borders of anatomical structures and is significantly more sensitive than the deterministic approach for quantification purposes. Furthermore, we demonstrate that an alternative tracking approach, called variational noise tracking, is qualitatively comparable with a standard probabilistic method, but is computationally less expensive, thus, enhancing its appeal for clinical applications.

Klein, Jan; Grötsch, Adrian; Betz, Daniel; Barbieri, Sebastiano; Friman, Ola; Stieltjes, Bram; Hildebrandt, Helmut; Hahn, Horst K.

2010-03-01

156

Quantitative x-ray fluorescence analysis using monochromatic synchrotron radiation  

SciTech Connect

The use of high-intensity, tunable monochromatic x-rays for the quantitative analysis of biological and geochemical specimens at the 10/sup -8/ g level is described. Incident x-rays were obtained from the new LBL-EXXON permanent magnet wiggler beamline at the Stanford Synchrotron Radiation Laboratory. The sample detector geometry was designed to make optimal use of polarization advantages for background reduction. Questions regarding the sensitivity and accuracy of the measurements were studied with particular emphasis on the advantages of tuning the x-ray energies for optimum excitation for specific elements. The implications of these measurements with respect to the use of x-ray microprobe beams will be discussed.

Jaklevic, J.M.; Giauque, R.D.; Thompson, A.C.

1984-09-01

157

Quantitative Image Analysis of HIV-1 Infection in Lymphoid Tissue  

NASA Astrophysics Data System (ADS)

Tracking human immunodeficiency virus-type 1 (HIV-1) infection at the cellular level in tissue reservoirs provides opportunities to better understand the pathogenesis of infection and to rationally design and monitor therapy A quantitative technique was developed to determine viral burden in two important cellular compartments in lymphoid tissues. Image analysis and in situ hybridization were combined to show that in the presymptomatic stages of infection there is a large, relatively stable pool of virions on the surfaces of follicular dendritic cells and a smaller pool of productively infected cells Despite evidence of constraints on HIV-1 replication in the infected cell population in lymphoid tissues, estimates of the numbers of these cells and the virus they could produce are consistent with the quantities of virus that have been detected in the bloodstream. The cellular sources of virus production and storage in lymphoid tissues can now be studied with this approach over the course of infection and treatment.

Haase, Ashley T.; Henry, Keith; Zupancic, Mary; Sedgewick, Gerald; Faust, Russell A.; Melroe, Holly; Cavert, Winston; Gebhard, Kristin; Staskus, Katherine; Zhang, Zhi-Qiang; Dailey, Peter J.; Balfour, Henry H., Jr.; Erice, Alejo; Perelson, Alan S.

1996-11-01

158

Quantitative genetic analysis of injury liability in infants and toddlers  

SciTech Connect

A threshold model of latent liability was applied to infant and toddler twin data on total count of injuries sustained during the interval from birth to 36 months of age. A quantitative genetic analysis of estimated twin correlations in injury liability indicated strong genetic dominance effects, but no additive genetic variance was detected. Because interpretations involving overdominance have little research support, the results may be due to low order epistasis or other interaction effects. Boys had more injuries than girls, but this effect was found only for groups whose parents were prompted and questioned in detail about their children`s injuries. Activity and impulsivity are two behavioral predictors of childhood injury, and the results are discussed in relation to animal research on infant and adult activity levels, and impulsivity in adult humans. Genetic epidemiological approaches to childhood injury should aid in targeting higher risk children for preventive intervention. 30 refs., 4 figs., 3 tabs.

Phillips, K.; Matheny, A.P. Jr. [Univ. of Louisville Medical School, KY (United States)

1995-02-27

159

Quantitative analysis of forest island pattern in selected Ohio landscapes  

SciTech Connect

The purpose of this study was to quantitatively describe the various aspects of regional distribution patterns of forest islands and relate those patterns to other landscape features. Several maps showing the forest cover of various counties in Ohio were selected as representative examples of forest patterns to be quantified. Ten thousand hectare study areas (landscapes) were delineated on each map. A total of 15 landscapes representing a wide variety of forest island patterns was chosen. Data were converted into a series of continuous variables which contained information pertinent to the sizes, shape, numbers, and spacing of woodlots within a landscape. The continuous variables were used in a factor analysis to describe the variation among landscapes in terms of forest island pattern. The results showed that forest island patterns are related to topography and other environmental features correlated with topography.

Bowen, G.W.; Burgess, R.L.

1981-07-01

160

Preparation of Buffers. An Experiment for Quantitative Analysis Laboratory  

NASA Astrophysics Data System (ADS)

In our experience, students who have a solid grounding in the theoretical aspects of buffers, buffer preparation, and buffering capacity are often at a loss when required to actually prepare a buffer in a research setting. However, there are very few published laboratory experiments pertaining to buffers. This laboratory experiment for the undergraduate quantitative analysis lab gives students hands-on experience in the preparation of buffers. By preparing a buffer to a randomly chosen pH value and comparing the theoretical pH to the actual pH, students apply their theoretical understanding of the Henderson-Hasselbalch equation, activity coefficients, and the effect of adding acid or base to a buffer. This experiment gives students experience in buffer preparation for research situations and helps them in advanced courses such as biochemistry where a fundamental knowledge of buffer systems is essential.

Buckley, P. T.

2001-10-01

161

Quantitative analysis of cardiomyocyte dynamics with optical coherence phase microscopy  

NASA Astrophysics Data System (ADS)

Spectral domain optical coherence microscopy (OCM) is an interferometric imaging technique for three-dimensional reconstruction of biological samples. Phase sensitive implementation of OCM has generally been in common path interferometer configuration to obtain high phase stability, which limits the numerical aperture of the imaging optics and the transverse resolution. Here, we describe the implementation of optical coherence phase microscope in asymmetric Linnik interferometer configuration, which provides phase stability of 0.5 milliradians along with high spatial resolution. Three-dimensional structural images and dynamic displacement images obtained from spontaneously active cardiomyocytes demonstrate that the phase information could potentially be used for quantitative analysis of contraction dynamics, spatially resolved to sub-cellular structures.

Ansari, Rehman; Aherrahrou, Redouane; Aherrahrou, Zouhair; Erdmann, Jeanette; Hüttmann, Gereon; Schweikard, Achim

2012-02-01

162

Quantitative analysis of gallstones using laser-induced breakdown spectroscopy  

SciTech Connect

The utility of laser-induced breakdown spectroscopy (LIBS) for categorizing different types of gallbladder stone has been demonstrated by analyzing their major and minor constituents. LIBS spectra of three types of gallstone have been recorded in the 200-900 nm spectral region. Calcium is found to be the major element in all types of gallbladder stone. The spectrophotometric method has been used to classify the stones. A calibration-free LIBS method has been used for the quantitative analysis of metal elements, and the results have been compared with those obtained from inductively coupled plasma atomic emission spectroscopy (ICP-AES) measurements. The single-shot LIBS spectra from different points on the cross section (in steps of 0.5 mm from one end to the other) of gallstones have also been recorded to study the variation of constituents from the center to the surface. The presence of different metal elements and their possible role in gallstone formation is discussed.

Singh, Vivek K.; Singh, Vinita; Rai, Awadhesh K.; Thakur, Surya N.; Rai, Pradeep K.; Singh, Jagdish P

2008-11-01

163

A Novel Quantitative Approach to Concept Analysis: The Internomological Network  

PubMed Central

Background When a construct such as patients’ transition to self-management of chronic illness is studied by researchers across multiple disciplines, the meaning of key terms can become confused. This results from inherent problems in language where a term can have multiple meanings (polysemy) and different words can mean the same thing (synonymy). Objectives To test a novel quantitative method for clarifying the meaning of constructs by examining the similarity of published contexts in which they are used. Method Published terms related to the concept transition to self-management of chronic illness were analyzed using the internomological network (INN), a type of latent semantic analysis to calculate the mathematical relationships between constructs based on the contexts in which researchers use each term. This novel approach was tested by comparing results to those from concept analysis, a best-practice qualitative approach to clarifying meanings of terms. By comparing results of the two methods, the best synonyms of transition to self-management, as well as key antecedent, attribute, and consequence terms, were identified. Results Results from INN analysis were consistent with those from concept analysis. The potential synonyms self-management, transition, and adaptation had the greatest utility. Adaptation was the clearest overall synonym, but had lower cross-disciplinary use. The terms coping and readiness had more circumscribed meanings. The INN analysis confirmed key features of transition to self-management, and suggested related concepts not found by the previous review. Discussion The INN analysis is a promising novel methodology that allows researchers to quantify the semantic relationships between constructs. The method works across disciplinary boundaries, and may help to integrate the diverse literature on self-management of chronic illness.

Cook, Paul F.; Larsen, Kai R.; Sakraida, Teresa J.; Pedro, Leli

2012-01-01

164

QTL analysis for some quantitative traits in bread wheat*  

PubMed Central

Quantitative trait loci (QTL) analysis was conducted in bread wheat for 14 important traits utilizing data from four different mapping populations involving different approaches of QTL analysis. Analysis for grain protein content (GPC) suggested that the major part of genetic variation for this trait is due to environmental interactions. In contrast, pre-harvest sprouting tolerance (PHST) was controlled mainly by main effect QTL (M-QTL) with very little genetic variation due to environmental interactions; a major QTL for PHST was detected on chromosome arm 3AL. For grain weight, one QTL each was detected on chromosome arms 1AS, 2BS and 7AS. QTL for 4 growth related traits taken together detected by different methods ranged from 37 to 40; nine QTL that were detected by single-locus as well as two-locus analyses were all M-QTL. Similarly, single-locus and two-locus QTL analyses for seven yield and yield contributing traits in two populations respectively allowed detection of 25 and 50 QTL by composite interval mapping (CIM), 16 and 25 QTL by multiple-trait composite interval mapping (MCIM) and 38 and 37 QTL by two-locus analyses. These studies should prove useful in QTL cloning and wheat improvement through marker aided selection.

Pushpendra, Kumar Gupta; Harindra, Singh Balyan; Pawan, Laxminarayan Kulwal; Neeraj, Kumar; Ajay, Kumar; Reyazul, Rouf Mir; Amita, Mohan; Jitendra, Kumar

2007-01-01

165

Quantitative TEM analysis of a hexagonal mesoporous silicate structure.  

PubMed

TEM analysis of mesoporous materials is generally undertaken to give qualitative results. Accurate quantitative analysis is demonstrated in this study. A systematic image analysis of a powder form of a hexagonal mesoporous material known as KIT-6 is conducted using a transmission electron microscope (TEM). Three types of image contrast typically appear in this material (a hexagonal honeycomb structure, wide and narrow parallel lines). The honeycomb face is used to characterise this material in terms of a conventional 2-D hexagonal structure and the d-spacings for the (100) and (110) planes are experimentally measured in varying focus conditions. A tilting experiment is conducted to determine how the angle of tilt affects the line spacing and their visibility. Tilting has very little effect on the line spacing, whereas it affects the visibility of both the wide and narrow lines by limiting an angle range of visibility. The hexagonal lattice structure parameter determined by TEM method is found to be approximately 7% lower than that calculated by low-angle X-ray diffraction. Thus we conclude that TEM data can be used to determine the geometry and dimensions of hexagonal mesoporous silica materials, with a small error in the hexagonal lattice parameter. PMID:16855727

Hudson, S; Tanner, D A; Redington, W; Magner, E; Hodnett, K; Nakahara, S

2006-06-21

166

Quantitative Medical Image Analysis for Clinical Development of Therapeutics  

NASA Astrophysics Data System (ADS)

There has been significant progress in development of therapeutics for prevention and management of several disease areas in recent years, leading to increased average life expectancy, as well as of quality of life, globally. However, due to complexity of addressing a number of medical needs and financial burden of development of new class of therapeutics, there is a need for better tools for decision making and validation of efficacy and safety of new compounds. Numerous biological markers (biomarkers) have been proposed either as adjunct to current clinical endpoints or as surrogates. Imaging biomarkers are among rapidly increasing biomarkers, being examined to expedite effective and rational drug development. Clinical imaging often involves a complex set of multi-modality data sets that require rapid and objective analysis, independent of reviewer's bias and training. In this chapter, an overview of imaging biomarkers for drug development is offered, along with challenges that necessitate quantitative and objective image analysis. Examples of automated and semi-automated analysis approaches are provided, along with technical review of such methods. These examples include the use of 3D MRI for osteoarthritis, ultrasound vascular imaging, and dynamic contrast enhanced MRI for oncology. Additionally, a brief overview of regulatory requirements is discussed. In conclusion, this chapter highlights key challenges and future directions in this area.

Analoui, Mostafa

167

Multiparent intercross populations in analysis of quantitative traits.  

PubMed

Most traits of interest to medical, agricultural and animal scientists show continuous variation and complex mode of inheritance. DNA-based markers are being deployed to analyse such complex traits, that are known as quantitative trait loci (QTL). In conventional QTL analysis, F2, backcross populations, recombinant inbred lines, backcross inbred lines and double haploids from biparental crosses are commonly used. Introgression lines and near isogenic lines are also being used for QTL analysis. However, such populations have major limitations like predominantly relying on the recombination events taking place in the F1 generation and mapping of only the allelic pairs present in the two parents. The second generation mapping resources like association mapping, nested association mapping and multiparent intercross populations potentially address the major limitations of available mapping resources. The potential of multiparent intercross populations in gene mapping has been discussed here. In such populations both linkage and association analysis can be conductted without encountering the limitations of structured populations. In such populations, larger genetic variation in the germplasm is accessed and various allelic and cytoplasmic interactions are assessed. For all practical purposes, across crop species, use of eight founders and a fixed population of 1000 individuals are most appropriate. Limitations with multiparent intercross populations are that they require longer time and more resource to be generated and they are likely to show extensive segregation for developmental traits, limiting their use in the analysis of complex traits. However, multiparent intercross population resources are likely to bring a paradigm shift towards QTL analysis in plant species. PMID:22546834

Rakshit, Sujay; Rakshit, Arunita; Patil, J V

2012-01-01

168

Building No. 905, showing typical aqua medias or rain hoods ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Building No. 905, showing typical aqua medias or rain hoods - Presidio of San Francisco, Enlisted Men's Barracks Type, West end of Crissy Field, between Pearce & Maudlin Streets, San Francisco, San Francisco County, CA

169

Quantitative analysis with the optoacoustic/ultrasound system OPUS  

NASA Astrophysics Data System (ADS)

The OPUS (Optoacoustic plus Ultrasound) system is a combination of a medical ultrasound scanner with a highrepetition rate, wavelength-tunable laser system and a suitable triggering interface to synchronize the laser and the ultrasound system. The pulsed laser generates an optoacoustic (OA), or photoacoustic (PA), signal which is detected by the ultrasound system. Alternatively, imaging in conventional ultrasound mode can be performed. Both imaging modes can be superimposed. The laser light is coupled into the tissue laterally, parallel to the ultrasound transducer, which does not require for any major modification to the transducer or the ultrasound beam forming. This was a basic requirement on the instrument, as the intention of the project was to establish the optoacoustic imaging modality as add-on to a conventional standard ultrasound instrument. We believe that this approach may foster the introduction of OA imaging as routine tool in medical diagnosis. Another key aspect of the project was to exploit the capabilities of OA imaging for quantitative analysis. The intention of the presented work is to summarize all steps necessary to extract the significant information from the PA raw data, which are required for the quantification of local absorber distributions. We show results of spatially resolved absorption measurements in scattering samples and a comparison of four different image reconstruction algorithms, regarding their influence on lateral resolution as well as on the signal to noise ratio for different sample depths and absorption values. The reconstruction algorithms are based on Fourier transformation, on a generalized 2D Hough transformation, on circular back-projection and the classical delay-and-sum approach which is implemented in most ultrasound scanners. Furthermore, we discuss the influence of a newly developed laser source, combining diode and flash lamp pumping. Compared to all-flash-lamp pumped systems it features a significantly higher pulse-to-pulse stability, which is required for sensitive and precise quantitative analyses.

Haisch, Christoph; Zell, Karin; Sperl, Jonathan; Vogel, Mika W.; Niessner, Reinhard

2009-02-01

170

Quantitative analysis and parametric display of regional myocardial mechanics  

NASA Astrophysics Data System (ADS)

Quantitative assessment of regional heart motion has significant potential for more accurate diagnosis of heart disease and/or cardiac irregularities. Local heart motion may be studied from medical imaging sequences. Using functional parametric mapping, regional myocardial motion during a cardiac cycle can be color mapped onto a deformable heart model to obtain better understanding of the structure- to-function relationships in the myocardium, including regional patterns of akinesis or diskinesis associated with ischemia or infarction. In this study, 3D reconstructions were obtained from the Dynamic Spatial Reconstructor at 15 time points throughout one cardiac cycle of pre-infarct and post-infarct hearts. Deformable models were created from the 3D images for each time point of the cardiac cycles. Form these polygonal models, regional excursions and velocities of each vertex representing a unit of myocardium were calculated for successive time-intervals. The calculated results were visualized through model animations and/or specially formatted static images. The time point of regional maximum velocity and excursion of myocardium through the cardiac cycle was displayed using color mapping. The absolute value of regional maximum velocity and maximum excursion were displayed in a similar manner. Using animations, the local myocardial velocity changes were visualized as color changes on the cardiac surface during the cardiac cycle. Moreover, the magnitude and direction of motion for individual segments of myocardium could be displayed. Comparison of these dynamic parametric displays suggest that the ability to encode quantitative functional information on dynamic cardiac anatomy enhances the diagnostic value of 4D images of the heart. Myocardial mechanics quantified this way adds a new dimension to the analysis of cardiac functional disease, including regional patterns of akinesis and diskinesis associated with ischemia and infarction. Similarly, disturbances in regional contractility and filling may be detected and evaluated using such measurements and displays.

Eusemann, Christian D.; Bellemann, Matthias E.; Robb, Richard A.

2000-04-01

171

Risk assessment of microcystin in dietary Aphanizomenon flos-aquae.  

PubMed

Aphanizomenon flos-aquae, a cyanobacterium that is marketed as a health food supplement, is harvested from natural blooms in Klamath Lake (Oregon) that are occasionally contaminated by Microcystis spp. Regulatory agencies in several countries are developing regulations to control the amount of microcystin in drinking water and other products, including products produced from A. flos-aquae. Regulation of microcystin (MC), a toxin produced by Microcystis spp. that is potentially present in natural culture of A. flos-aquae, should be based on studies in which a test species is exposed to the natural mixture of these cyanobacteria. A 1984 feeding trial to determine the effects of high dietary levels of A. flos-aquae on reproduction and development of mice is reanalyzed in light of recent analyses for microcystin-LR (MCLR) in the diets of those mice. Young adult mice consuming up to 333 microg MCLR/kg body weight (bw)/day exhibited no adverse effects on growth and reproduction, fetal development, and survival and organ weights of neonates. Based on a NOAEL of 333 microg MCLR/kg bw/day, a safety factor of 1000, consumption of 2 g/day of A. flos-aquae by a 60-kg adult, the safe level of MCLR as a contaminant of A. flos-aquae products is calculated to be 10.0 microg MCLR/g. PMID:10499991

Schaeffer, D J; Malpas, P B; Barton, L L

1999-09-01

172

Quantitative and qualitative analysis of rhinovirus infection in bronchial tissues.  

PubMed

Although rhinovirus (RV) infections can cause asthma exacerbations and alter lower airway inflammation and physiology, it is unclear how important bronchial infection is to these processes. To study the kinetics, location, and frequency of RV appearance in lower airway tissues during an acute infection, immunohistochemistry and quantitative polymerase chain reaction analysis were used to analyze the presence of virus in cells from nasal lavage, sputum, bronchoalveolar lavage, bronchial brushings, and biopsy specimens from 19 subjects with an experimental RV serotype 16 (RV16) cold. RV was detected by polymerase chain reaction analysis on cells from nasal lavage and induced sputum samples from all subjects after RV16 inoculation, as well as in 5 of 19 bronchoalveolar lavage cell samples and in 5 of 18 bronchial biopsy specimens taken 4 days after virus inoculation. Immunohistochemistry detected RV16 in 39 and 36% of all biopsy and brushing samples taken 4 and 15 days, respectively, after inoculation. Infected cells were primarily distributed in discrete patches on the epithelium. These results confirm that infection of lower airway tissues is a frequent finding during a cold and further demonstrate a patchy distribution of infected cells, a pattern similar to that reported in upper airway tissues. PMID:15591468

Mosser, Anne G; Vrtis, Rose; Burchell, Lacinda; Lee, Wai-Ming; Dick, Claire R; Weisshaar, Elizabeth; Bock, Diane; Swenson, Cheri A; Cornwell, Richard D; Meyer, Keith C; Jarjour, Nizar N; Busse, William W; Gern, James E

2004-12-10

173

Optimal display conditions for quantitative analysis of stereoscopic cerebral angiograms  

SciTech Connect

For several years the authors have been using a stereoscopic display as a tool in the planning of stereotactic neurosurgical techniques. This PC-based workstation allows the surgeon to interact with and view vascular images in three dimensions, as well as to perform quantitative analysis of the three-dimensional (3-D) space. Some of the perceptual issues relevant to the presentation of medical images on this stereoscopic display were addressed in five experiments. The authors show that a number of parameters--namely the shape, color, and depth cue, associated with a cursor--as well as the image filtering and observer position, have a role in improving the observer`s perception of a 3-D image and his ability to localize points within the stereoscopically presented 3-D image. However, an analysis of the results indicates that while varying these parameters can lead to an effect on the performance of individual observers, the effects are not consistent across observers, and the mean accuracy remains relatively constant under the different experimental conditions.

Charland, P. [McGill Univ., Montreal, Quebec (Canada). Medical Physics Unit; Peters, T. [Montreal Neurological Inst., Montreal, Quebec (Canada)]|[McGill Univ., Montreal, Quebec (Canada). Dept. of Biomedical Engineering

1996-10-01

174

Quantitative analysis of fluorescence lifetime imaging made easy  

PubMed Central

Fluorescence lifetime imaging is a valuable and versatile tool for the investigation of the molecular environment of fluorophores in living cells. It is ideally suited—and is therefore increasingly used—for the quantification of the occurrence of Förster Resonance Energy Transfer, a powerful microscopy method for the detection of subnanometer conformational changes, protein-protein interactions, and protein biochemical status. However, careful quantitative analysis is required for the correct and meaningful interpretation of fluorescence lifetime data. This can be a daunting task to the nonexpert user, and is the source for many avoidable errors and unsound interpretations. Digman and colleagues (Digman et al., 2007, Biophys. J. 94, L14–6) present an analysis technique that avoids data fitting in favor of a simple graphical polar data representation. In this “phasor” space, the physics of lifetime imaging becomes more intuitive and accessible also to the inexperienced user. The cumulated information from image pixels, even over different cells, describes patterns and trajectories that can be visually interpreted in physically meaningful ways. Its usefulness is demonstrated in the study of the dimerization of the uPAR receptor (Caiolfa et al., 2007, J. Cell Biol. 179, 1067–1082).

Wouters, Fred S.; Esposito, Alessandro

2008-01-01

175

Quantitative RNA-seq analysis of the Campylobacter jejuni transcriptome  

PubMed Central

Campylobacter jejuni is the most common bacterial cause of foodborne disease in the developed world. Its general physiology and biochemistry, as well as the mechanisms enabling it to colonize and cause disease in various hosts, are not well understood, and new approaches are required to understand its basic biology. High-throughput sequencing technologies provide unprecedented opportunities for functional genomic research. Recent studies have shown that direct Illumina sequencing of cDNA (RNA-seq) is a useful technique for the quantitative and qualitative examination of transcriptomes. In this study we report RNA-seq analyses of the transcriptomes of C. jejuni (NCTC11168) and its rpoN mutant. This has allowed the identification of hitherto unknown transcriptional units, and further defines the regulon that is dependent on rpoN for expression. The analysis of the NCTC11168 transcriptome was supplemented by additional proteomic analysis using liquid chromatography-MS. The transcriptomic and proteomic datasets represent an important resource for the Campylobacter research community.

Chaudhuri, Roy R.; Yu, Lu; Kanji, Alpa; Perkins, Timothy T.; Gardner, Paul P.; Choudhary, Jyoti; Maskell, Duncan J.

2011-01-01

176

Topographic Quantitative EEG Response to Acute Caffeine Withdrawal: A Comprehensive Analysis of Multiple Quantitative Variables  

Microsoft Academic Search

Most previous studies of the neurophysiological effects of caffeine have focused on the effects of caffeine ingestion, and few studies have examined the effects of caffeine withdrawal. This open study evaluated the quantitative EEG (QEEG) changes occurring during a 4-day period of abstinence in subjects who habitually consume 300 mg or more of caffeine daily. Thirteen subjects underwent QEEG studies

Roy R. Reeves; Frederick A. Struve; Gloria Patrick

2002-01-01

177

Morpholinium 2,4-dinitrophenolate Aqua Salt and Ethylenediammonium 2,4-dinitrophenolate Aqua Salt  

Microsoft Academic Search

\\u000a Abstract  The structures of the aqua salts of 2,4-dinitrophenolate (2,4-DNP?) with ethylenediammonium (EDA2+) and morpholinium (MP+) have been determined by X-ray diffraction, the first with 2:1 stoichiometry. The EDA2+ salt crystallizes in P21\\/c space group, with a = 5.887; b = 23.441; c = 7.075, ? = 96.61, R1 = 0.0365 for reflections with Fo > 4sig(Fo). MP+ salt crystallizes as P–1 space group; a = 6.655; b = 9.388 c = 11.452; ? = 104.82 ? = 102.31 ? = 105.24, with

Márcio Lazzarotto; Eduardo Ernesto Castellano; Francine Furtado Nachtigall

2007-01-01

178

Teaching Quantitative Literacy through a Regression Analysis of Exam Performance  

ERIC Educational Resources Information Center

Quantitative literacy is increasingly essential for both informed citizenship and a variety of careers. Though regression is one of the most common methods in quantitative sociology, it is rarely taught until late in students' college careers. In this article, the author describes a classroom-based activity introducing students to regression…

Lindner, Andrew M.

2012-01-01

179

Teaching Quantitative Literacy through a Regression Analysis of Exam Performance  

ERIC Educational Resources Information Center

|Quantitative literacy is increasingly essential for both informed citizenship and a variety of careers. Though regression is one of the most common methods in quantitative sociology, it is rarely taught until late in students' college careers. In this article, the author describes a classroom-based activity introducing students to regression…

Lindner, Andrew M.

2012-01-01

180

Combining Quantitative and Qualitative Approaches in Poverty Analysis  

Microsoft Academic Search

Economics is commonly associated with the use of quantitative methods, and because of this, supposedly, the discipline is more “rigorous” than other social sciences, which are in turn associated with the application of qualitative methods, presumed to be less rigorous. This paper challenges these assumptions and argues that the more serious distinction, which applies both to quantitative and to qualitative

Howard White

2002-01-01

181

The Quantitative Analysis of an Analgesic Tablet: An NMR Experiment for the Instrumental Analysis Course  

Microsoft Academic Search

A quantitative analysis experiment is outlined that uses 13C NMR. Initial work utilizes a known compound (acenapthene) to assess the type of NMR experiment necessary to achieve a proportional response from all of the carbons in the compound. Both gated decoupling and inverse gated decoupling routines with a variety of delay times are inspected, in addition to investigation of paramagnetic

Thomas A. Schmedake; Lawrence E. Welch

1996-01-01

182

Effectiveness of cleaning surgical implants: quantitative analysis of contaminant removal.  

PubMed

Surgical implants need to be free from contaminants before implantation. The effectiveness of a presently used Clemson bioengineering cleaning (CBC) protocol was evaluated for cleaning three different biomaterials (titanium, aluminum oxide, and polyethylene terephthalate, PET) contaminated with three different contaminants (calcium chloride, zinc chloride, and hexadecane). Radiolabeled tracer analysis (RTA), with the use of liquid scintillation, was used as the surface analytical technique to quantitatively determine the percent contaminant removed from the biomaterial surface. On average, the ultrasonic cleaning step removed 99.96% of all three contaminants from both titanium and aluminum oxide. The CBC protocol did not sufficiently clean PET fabric contaminated with hexadecane leaving 11.76% of the contaminant after the ultrasonic step. With the use of isopropyl alcohol in series with 1% Liquinox, the ultrasonic step cleaned the fabric soiled with hexadecane within 30 min, removing 99.85% of the hexadecane initially on the surface. RTA proved to be an excellent method of quantifying surface contamination on implant materials, and for assessing the effectiveness of cleaning protocols in question. PMID:7703533

Rowland, S A; Shalaby, S W; Latour, R A; von Recum, A F

1995-01-01

183

Genomewide Analysis of Epistatic Effects for Quantitative Traits in Barley  

PubMed Central

The doubled-haploid (DH) barley population (Harrington × TR306) developed by the North American Barley Genome Mapping Project (NABGMP) for QTL mapping consisted of 145 lines and 127 markers covering a total genome length of 1270 cM. These DH lines were evaluated in ?25 environments for seven quantitative traits: heading, height, kernel weight, lodging, maturity, test weight, and yield. We applied an empirical Bayes method that simultaneously estimates 127 main effects for all markers and 127(127?1)/2=8001 interaction effects for all marker pairs in a single model. We found that the largest main-effect QTL (single marker) and the largest epistatic effect (single pair of markers) explained ?18 and 2.6% of the phenotypic variance, respectively. On average, the sum of all significant main effects and the sum of all significant epistatic effects contributed 35 and 6% of the total phenotypic variance, respectively. Epistasis seems to be negligible for all the seven traits. We also found that whether two loci interact does not depend on whether or not the loci have individual main effects. This invalidates the common practice of epistatic analysis in which epistatic effects are estimated only for pairs of loci of which both have main effects.

Xu, Shizhong; Jia, Zhenyu

2007-01-01

184

Regulators of yeast endocytosis identified by systematic quantitative analysis  

PubMed Central

Endocytosis of receptors at the plasma membrane is controlled by a complex mechanism that includes clathrin, adaptors, and actin regulators. Many of these proteins are conserved in yeast yet lack observable mutant phenotypes, which suggests that yeast endocytosis may be subject to different regulatory mechanisms. Here, we have systematically defined genes required for internalization using a quantitative genome-wide screen that monitors localization of the yeast vesicle-associated membrane protein (VAMP)/synaptobrevin homologue Snc1. Genetic interaction mapping was used to place these genes into functional modules containing known and novel endocytic regulators, and cargo selectivity was evaluated by an array-based comparative analysis. We demonstrate that clathrin and the yeast AP180 clathrin adaptor proteins have a cargo-specific role in Snc1 internalization. We additionally identify low dye binding 17 (LDB17) as a novel conserved component of the endocytic machinery. Ldb17 is recruited to cortical actin patches before actin polymerization and regulates normal coat dynamics and actin assembly. Our findings highlight the conserved machinery and reveal novel mechanisms that underlie endocytic internalization.

Burston, Helen E.; Maldonado-Baez, Lymarie; Davey, Michael; Montpetit, Benjamen; Schluter, Cayetana; Wendland, Beverly

2009-01-01

185

Quantitative analysis of chromosome motion in Drosophila melanogaster  

NASA Astrophysics Data System (ADS)

We present an algorithm for estimating nonrigid motion of chromosomes in 4D microscopic images. Chromosomes are represented by a graph and motion estimation is formulated as a graph matching problem. All chromosomes within the graph are located, and then simulated annealing is used to find the mapping of chromosomes at time t onto chromosomes at time t+1 that minimizes the integrated displacement along each chromosome. Results with actual 4D images indicate that this model-based approach is sufficiently robust to correctly track the motion of chromosomes under conditions of limited spatial and temporal resolution. Using the motion estimate, previously developed methods for the quantitative analysis of 3D structure are extended to four dimensions, allowing chromosome mobility, flexibility, and interactions to be measured. Application of these algorithms to 4D images of Drosophila metaphase chromosomes in vivo allows visualization of clearly defined domains of high chromosomal flexibility, as well as other regions of distinctly lower chromosomal mobility which may coincide with centrometers.

Marshall, Wallace F.; Agard, David A.; Sedat, John W.

1995-03-01

186

Quantitative Analysis of Cellular Metabolic Dissipative, Self-Organized Structures  

PubMed Central

One of the most important goals of the postgenomic era is understanding the metabolic dynamic processes and the functional structures generated by them. Extensive studies during the last three decades have shown that the dissipative self-organization of the functional enzymatic associations, the catalytic reactions produced during the metabolite channeling, the microcompartmentalization of these metabolic processes and the emergence of dissipative networks are the fundamental elements of the dynamical organization of cell metabolism. Here we present an overview of how mathematical models can be used to address the properties of dissipative metabolic structures at different organizational levels, both for individual enzymatic associations and for enzymatic networks. Recent analyses performed with dissipative metabolic networks have shown that unicellular organisms display a singular global enzymatic structure common to all living cellular organisms, which seems to be an intrinsic property of the functional metabolism as a whole. Mathematical models firmly based on experiments and their corresponding computational approaches are needed to fully grasp the molecular mechanisms of metabolic dynamical processes. They are necessary to enable the quantitative and qualitative analysis of the cellular catalytic reactions and also to help comprehend the conditions under which the structural dynamical phenomena and biological rhythms arise. Understanding the molecular mechanisms responsible for the metabolic dissipative structures is crucial for unraveling the dynamics of cellular life.

de la Fuente, Ildefonso Martinez

2010-01-01

187

Critical evaluation of quantitative colocalization analysis in confocal fluorescence microscopy.  

PubMed

Spatial colocalization of fluorescently labeled proteins can reveal valuable information about proteinprotein interactions. Compared to qualitative visual interpretation of dual color images, quantitative colocalization analysis (QCA) provides more objective evaluations to the degree of colocalization. However, the finite resolution power of microscopes and the spatial patterns of intracellular structures may compromise the reliability of many classical QCA methods. In this paper, we discuss the strength and weakness of some mostly used QCA methods. By studying their applications on computer-simulated images and biological images, we show that classical pixel intensity based QCA methods are often vulnerable to coincidental overlapping among resolution elements (resel) distributions and thus not suitable to images with high molecular density or with low resolution. Also, many QCA methods can mistakenly regard long range correlation as colocalization due to protein localization in intracellular structures. The newly developed protein-protein index (PPI) approach is able to reduce the influence from resel overlapping and spatial intracellular pattern compared to previous methods, significantly improving the reliability of QCA. PMID:22392274

Wu, Yong; Zinchuk, Vadim; Grossenbacher-Zinchuk, Olga; Stefani, Enrico

2012-03-06

188

Quantitative analysis of protein dynamics during asymmetric cell division.  

PubMed

In dividing Drosophila sensory organ precursor (SOP) cells, the fate determinant Numb and its associated adaptor protein Pon localize asymmetrically and segregate into the anterior daughter cell, where Numb influences cell fate by repressing Notch signaling. Asymmetric localization of both proteins requires the protein kinase aPKC and its substrate Lethal (2) giant larvae (Lgl). Because both Numb and Pon localization require actin and myosin, lateral transport along the cell cortex has been proposed as a possible mechanism for their asymmetric distribution. Here, we use quantitative live analysis of GFP-Pon and Numb-GFP fluorescence and fluorescence recovery after photobleaching (FRAP) to characterize the dynamics of Numb and Pon localization during SOP division. We demonstrate that Numb and Pon rapidly exchange between a cytoplasmic pool and the cell cortex and that preferential recruitment from the cytoplasm is responsible for their asymmetric distribution during mitosis. Expression of a constitutively active form of aPKC impairs membrane recruitment of GFP-Pon. This defect can be rescued by coexpression of nonphosphorylatable Lgl, indicating that Lgl is the main target of aPKC. We propose that a high-affinity binding site is asymmetrically distributed by aPKC and Lgl and is responsible for asymmetric localization of cell-fate determinants during mitosis. PMID:16243032

Mayer, Bernd; Emery, Gregory; Berdnik, Daniela; Wirtz-Peitz, Frederik; Knoblich, Juergen A

2005-10-25

189

Quantitative sum rule analysis of low-temperature spectral functions  

NASA Astrophysics Data System (ADS)

We analyze QCD and Weinberg-type sum rules in a low-temperature pion gas using vector and axial-vector spectral functions following from the model-independent chiral-mixing scheme. Toward this end we employ recently constructed vacuum spectral functions with ground and first-excited states in both channels and a universal perturbative continuum; they quantitatively describe hadronic ?-decay data and satisfy vacuum sum rules. These features facilitate the implementation of chiral mixing without further assumptions, and lead to in-medium spectral functions which exhibit a mutual tendency of compensating resonance and dip structures, suggestive for an approach toward structureless distributions. In the sum rule analysis, we account for pion mass corrections, which turn out to be significant. While the Weinberg sum rules remain satisfied even at high temperatures, the numerical evaluation of the QCD sum rules for vector and axial-vector channels reveals significant deviations setting in for temperatures beyond ˜140MeV, suggestive of additional physics beyond low-energy chiral pion dynamics.

Holt, Nathan P. M.; Hohler, Paul M.; Rapp, Ralf

2013-04-01

190

Quantitative analysis of carbon in silicon carbide coated with carbon.  

PubMed

Nonconductive specimens for scanning electron microscopy or X-ray microanalysis are coated with conductive carbon in order to reduce charging. But carbon film absorbs X-ray fluxes causing errors in measuring chemical composition. Especially when the carbon content is measured, carbon coating not only blocks X-rays but also becomes a source of carbon X-rays. It is thus necessary to determine how much errors are induced by carbon coating, and how thick coating is allowed for the accurate measurement. In this study, quantitative analysis of carbon on silicon carbide with carbon coating films was attempted by electron probe microanalyzer. It was found that measured carbon content increased in a nonlinear manner up to 40% with a film thickness, whereas silicon content decreased slightly. Carbon X-ray intensity was determined by computer simulation, which increased in a linear manner with the thickness. The discrepancy was due to a nucleation and growth of islands and thus a change of density with a thickening of coating film. PMID:23920162

Lee, Hongrim; Kim, Junsu; Yun, Jondo

2013-08-01

191

Management of patients with symptomatic gallstones: a quantitative analysis.  

PubMed

Should persons with symptomatic gallstones (i.e., those that have caused biliary pain) be treated immediately? Or may they be managed expectantly until pain recurs or a biliary complication (i.e., acute cholecystitis or pancreatitis) occurs? To assess the mortality risk of different strategies, we performed a quantitative analysis. For the expectant management strategy that requires surgery only if a biliary complication occurs, the cumulative lifetime probability of gallstone disease death in a 30-year-old man is about 2%, and most deaths occur after age 65. In comparison, elective cholecystectomy has only a 0.1% rate of gallstone disease death, but all deaths occur at age 30. The average amount of life expectancy gained by immediate cholecystectomy compared with expectant management is 52 days, which is reduced to 23 days using 5% discounting. This gain could be increased only slightly by a 100% effective and risk-free therapy such as perfected lithotripsy or medical dissolution. Results are similar for women. The results suggest that, for persons with symptomatic gallstones, the life expectancy gain of immediate cholecystectomy is relatively small and that the potential incremental gain of nonsurgical therapy is also small. For patients and physicians who believe that life expectancy is of primary consideration, the decision about therapy may be made primarily on non-mortality considerations. Some patients and physicians may decide that the risk of symptomatic gallstones is low enough that a policy of expectant management may be acceptable. PMID:2405659

Ransohoff, D F; Gracie, W A

1990-02-01

192

Comparison of multivariate calibration methods for quantitative spectral analysis  

SciTech Connect

The quantitative prediction abilities of four multivariate calibration methods for spectral analyses are compared by using extensive Monte Carlo simulations. The calibration methods compared include inverse least-squares (ILS), classical least-squares (CLS), partial least-squares (PLS), and principal component regression (PCR) methods. ILS is a frequency-limited method while the latter three are capable of full-spectrum calibration. The simulations were performed assuming Beer's law holds and that spectral measurement errors and concentration errors associated with the reference method are normally distributed. Eight different factors that could affect the relative performance of the calibration methods were varied in a two-level, eight-factor experimental design in order to evaluate their effect on the prediction abilities of the four methods. It is found that each of the three full-spectrum methods has its range of superior performance. The frequency-limited ILS method was never the best method, although in the presence of relatively large concentration errors it sometimes yields comparable analysis precision to the full-spectrum methods for the major spectral component. The importance of each factor in the absolute and relative performances of the four methods is compared.

Thomas, E.V.; Haaland, D.M. (Sandia National Laboratories, Albuquerque, NM (USA))

1990-05-15

193

Quantitative Analysis and Characterization of DNA Immobilized on Gold.  

National Technical Information Service (NTIS)

We describe the complementary use of X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy to quantitatively characterize the immobilization of thiolated (dT)25 single- stranded DNA (ssDNA) on gold. When electron attenu...

D. Y. Petrovykh H. Kimura-Suda L. J. Whitman M. J. Tarlov

2003-01-01

194

Quantitative analysis of the new biologically active natural substance shunlite  

Microsoft Academic Search

Methods for the quantitative determination of chemical elements contained in shunlite — a new biologically active natural\\u000a substance — have been developed. The proposed methods are characterized by high accuracy and reproducibility.

O. Yu. Vasil’eva; M. S. Goizman; G. B. Tikhomirova; A. S. Berlyand; A. S. Alikhanyan; A. V. Shevyakov

2007-01-01

195

Quantitative Analysis of p-Phthalic Acid by Infrared Spectrum.  

National Technical Information Service (NTIS)

A quantitative method is described for determining p-phthalic acid in synthetic resins, synthetic fibers, and plastifiers by infrared absorption spectrum. The apparatus used was a infrared spectrometer. Infrared absorption spectra of p- and o-phthalic aci...

Ch'en Chang-ch'iang Chang Yu-ch'ien

1968-01-01

196

Quantitative analysis of klimont, a new natural biologically active preparation  

Microsoft Academic Search

A method for quantitative determination of silicon, aluminum, and iron, the main active components in the natural biologically\\u000a active preparation klimont, is developed that ensures good reproducibility and accuracy. The limits for the content of these\\u000a elements are established and can be introduced into the “Quantitative Determination” section of the draft manufacturer’s pharmacopoeial\\u000a monograph for klimont.

A. N. Zhuchkov; A. S. Berlyand; M. S. Goizman; G. B. Tikhomirova; V. I. Yakusheva

2009-01-01

197

Quantitative analysis of synaptic boutons in Drosophila primary neuronal cultures  

Microsoft Academic Search

Little information is currently available for structural and quantitative aspects of Drosophila central synapses due to difficulties in accessing those synapses in the tiny fly brain. Here, we developed a new approach to quantitatively analyze central synapses using Drosophila primary neuronal cultures. Two different markers were used to identify synaptic boutons: GFP marking with a synaptotagmin (Syt)::eGFP transgene and anti-Syt

Kauroon Darya; Archan Ganguly; Daewoo Lee

2009-01-01

198

Analysis of quantitative phase detection based on optical information processing  

NASA Astrophysics Data System (ADS)

Phase object exists widely in nature, such as biological cells, optical components, atmospheric flow field and so on. The phase detection of objects has great significance in the basic research, nondestructive testing, aerospace, military weapons and other areas. The usual methods of phase object detection include interference method, grating method, schlieren method, and phase-contrast method etc. These methods have their own advantages, but they also have some disadvantages on detecting precision, environmental requirements, cost, detection rate, detection range, detection linearity in various applications, even the most sophisticated method-phase contrast method mainly used in microscopic structure, lacks quantitative analysis of the size of the phase of the object and the relationship between the image contrast and the optical system. In this paper, various phase detection means and the characteristics of different applications are analyzed based on the optical information processing, and a phase detection system based on optical filtering is formed. Firstly the frequency spectrum of the phase object is achieved by Fourier transform lens in the system, then the frequency spectrum is changed reasonably by the filter, at last the image which can represent the phase distribution through light intensity is achieved by the inverse Fourier transform. The advantages and disadvantages of the common used filters such as 1/4 wavelength phase filter, high-pass filter and edge filter are analyzed, and their phase resolution is analyzed in the same optical information processing system, and the factors impacting phase resolution are pointed out. The paper draws a conclusion that there exists an optimal filter which makes the detect accuracy best for any application. At last, we discussed how to design an optimal filter through which the ability of the phase testing of optical information processing system can be improved most.

Tao, Wang; Tu, Jiang-Chen; Chun, Kuang-Tao; Yu, Han-Wang; Xin, Du

2009-07-01

199

Quantitative Proteomics Analysis of Inborn Errors of Cholesterol Synthesis  

PubMed Central

Smith-Lemli-Opitz syndrome (SLOS) and lathosterolosis are malformation syndromes with cognitive deficits caused by mutations of 7-dehydrocholesterol reductase (DHCR7) and lathosterol 5-desaturase (SC5D), respectively. DHCR7 encodes the last enzyme in the Kandutsch-Russel cholesterol biosynthetic pathway, and impaired DHCR7 activity leads to a deficiency of cholesterol and an accumulation of 7-dehydrocholesterol. SC5D catalyzes the synthesis of 7-dehydrocholesterol from lathosterol. Impaired SC5D activity leads to a similar deficiency of cholesterol but an accumulation of lathosterol. Although the genetic and biochemical causes underlying both syndromes are known, the pathophysiological processes leading to the developmental defects remain unclear. To study the pathophysiological mechanisms underlying SLOS and lathosterolosis neurological symptoms, we performed quantitative proteomics analysis of SLOS and lathosterolosis mouse brain tissue and identified multiple biological pathways affected in Dhcr7?3–5/?3–5 and Sc5d?/? E18.5 embryos. These include alterations in mevalonate metabolism, apoptosis, glycolysis, oxidative stress, protein biosynthesis, intracellular trafficking, and cytoskeleton. Comparison of proteome alterations in both Dhcr7?3–5/?3–5 and Sc5d?/? brain tissues helps elucidate whether perturbed protein expression was due to decreased cholesterol or a toxic effect of sterol precursors. Validation of the proteomics results confirmed increased expression of isoprenoid and cholesterol synthetic enzymes. This alteration of isoprenoid synthesis may underlie the altered posttranslational modification of Rab7, a small GTPase that is functionally dependent on prenylation with geranylgeranyl, that we identified and validated in this study. These data suggested that although cholesterol synthesis is impaired in both Dhcr7?3–5/?3–5 and Sc5d?/? embryonic brain tissues the synthesis of nonsterol isoprenoids may be increased and thus contribute to SLOS and lathosterolosis pathology. This proteomics study has provided insight into the pathophysiological mechanisms of SLOS and lathosterolosis, and understanding these pathophysiological changes will help guide clinical therapy for SLOS and lathosterolosis.

Jiang, Xiao-Sheng; Backlund, Peter S.; Wassif, Christopher A.; Yergey, Alfred L.; Porter, Forbes D.

2010-01-01

200

Hydrocarbons On Phoebe, Iapetus, And Hyperion: Quantitative Analysis  

NASA Astrophysics Data System (ADS)

We present a quantitative analysis of the hydrocarbon spectral bands measured on three of Saturn's satellites, Phoebe, Iapetus, and Hyperion. These bands, measured with the Cassini Visible-Infrared Mapping Spectrometer on close fly-bys of these satellites, are the C-H stretching modes of aromatic hydrocarbons at 3.28 ?m ( 3050 cm-1), and the are four blended bands of aliphatic -CH2- and -CH3 in the range 3.36-3.52 ?m ( 2980-2840 cm-1). In these data, the aromatic band, probably indicating the presence of polycyclic aromatic hydrocarbons (PAH) is unusually strong in comparison to the aliphatic bands, resulting in a unique signature among Solar System bodies measured so far, and as such offers a means of comparison among the three satellites. The ratio of the C-H bands in aromatic molecules to those in aliphatic molecules in the surface materials of Phoebe, NAro:NAliph 24; for Hyperion the value is 12, while Iapetus shows an intermediate value. In view of the trend of the evolution (dehydrogenation by heat and radiation) of aliphatic complexes toward more compact molecules and eventually to aromatics, the relative abundances of aliphatic -CH2- and -CH3- is an indication of the lengths of the molecular chain structures, hence the degree of modification of the original material. We derive CH2:CH3 2.2 in the spectrum of low-albedo material on Iapetus; this value is the same within measurement errors to the ratio in the diffuse interstellar medium. The similarity in the spectral signatures of the three satellites, plus the apparent weak trend of aromatic/aliphatic abundance from Phoebe to Hyperion, is consistent with, and effectively confirms that the source of the hydrocarbon-bearing material is Phoebe, and that the appearance of that material on the other two satellites arises from the deposition of the inward-spiraling dust that populates the Phoebe ring.

Cruikshank, Dale P.; Dalle Ore, C. M.; Pendleton, Y. J.; Clark, R. N.

2012-10-01

201

Quantitative Analysis of the Effective Functional Structure in Yeast Glycolysis  

PubMed Central

The understanding of the effective functionality that governs the enzymatic self-organized processes in cellular conditions is a crucial topic in the post-genomic era. In recent studies, Transfer Entropy has been proposed as a rigorous, robust and self-consistent method for the causal quantification of the functional information flow among nonlinear processes. Here, in order to quantify the functional connectivity for the glycolytic enzymes in dissipative conditions we have analyzed different catalytic patterns using the technique of Transfer Entropy. The data were obtained by means of a yeast glycolytic model formed by three delay differential equations where the enzymatic rate equations of the irreversible stages have been explicitly considered. These enzymatic activity functions were previously modeled and tested experimentally by other different groups. The results show the emergence of a new kind of dynamical functional structure, characterized by changing connectivity flows and a metabolic invariant that constrains the activity of the irreversible enzymes. In addition to the classical topological structure characterized by the specific location of enzymes, substrates, products and feedback-regulatory metabolites, an effective functional structure emerges in the modeled glycolytic system, which is dynamical and characterized by notable variations of the functional interactions. The dynamical structure also exhibits a metabolic invariant which constrains the functional attributes of the enzymes. Finally, in accordance with the classical biochemical studies, our numerical analysis reveals in a quantitative manner that the enzyme phosphofructokinase is the key-core of the metabolic system, behaving for all conditions as the main source of the effective causal flows in yeast glycolysis.

De la Fuente, Ildefonso M.; Cortes, Jesus M.

2012-01-01

202

Tropospheric Temperature Trends on Decadal Scale from Measurements on Aqua  

NASA Astrophysics Data System (ADS)

We use the Atmospheric Infrared Sounder (AIRS) and Advance Microwave Sounding Unit (AMSU) measurements carried out on Aqua satellite in 2002-2011 to infer mid-tropospheric temperature variability on decadal time scale. Since AMSU soundings are independent on the CO2 its measurements track natural climate variability. However the AIRS sounding channels at AMSU comparable levels are sensitive to the changes in CO2. The difference between AIRS and AMSU removes the natural variability and reveals the variability of CO2. The trend in AIRS data is determined accurately. Thus its surface channels drift less than 5 mK/yr based on the validation with sea surface temperatures measured by ocean buys. The AMSU weighing functions do not localized near the sea surface. Comparison of trends in the difference record with the CO2 trends found from the ground stations and with the trends determined directly from the mid-tropospheric global CO2 retrieved from the same satellite data allows us to evaluate the long-term stability of the widely used AMSU measurements, and, once the stability is established, to use the AMSU-AIRS difference records for diagnostic of the atmospheric CO2 data. The analysis of AMSU-AIRS differences reveals different trends over oceans, over localized land regions, and zonally averaged regions, which we interpret as related to CO2 transport effects. This work was supported by the Jet Propulsion Laboratory of the California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

Ruzmaikin, A.; Aumann, H. H.

2011-12-01

203

Quantitative Analysis by Isotopic Dilution Using Mass Spectroscopy: The Determination of Caffeine by GC-MS.  

ERIC Educational Resources Information Center

Describes a laboratory technique for quantitative analysis of caffeine by an isotopic dilution method for coupled gas chromatography-mass spectroscopy. Discusses caffeine analysis and experimental methodology. Lists sample caffeine concentrations found in common products. (MVL)

Hill, Devon W.; And Others

1988-01-01

204

Quantitative Analysis by Isotopic Dilution Using Mass Spectroscopy: The Determination of Caffeine by GC-MS.  

ERIC Educational Resources Information Center

|Describes a laboratory technique for quantitative analysis of caffeine by an isotopic dilution method for coupled gas chromatography-mass spectroscopy. Discusses caffeine analysis and experimental methodology. Lists sample caffeine concentrations found in common products. (MVL)|

Hill, Devon W.; And Others

1988-01-01

205

Universal platform for quantitative analysis of DNA transposition  

PubMed Central

Background Completed genome projects have revealed an astonishing diversity of transposable genetic elements, implying the existence of novel element families yet to be discovered from diverse life forms. Concurrently, several better understood transposon systems have been exploited as efficient tools in molecular biology and genomics applications. Characterization of new mobile elements and improvement of the existing transposition technology platforms warrant easy-to-use assays for the quantitative analysis of DNA transposition. Results Here we developed a universal in vivo platform for the analysis of transposition frequency with class II mobile elements, i.e., DNA transposons. For each particular transposon system, cloning of the transposon ends and the cognate transposase gene, in three consecutive steps, generates a multifunctional plasmid, which drives inducible expression of the transposase gene and includes a mobilisable lacZ-containing reporter transposon. The assay scores transposition events as blue microcolonies, papillae, growing within otherwise whitish Escherichia coli colonies on indicator plates. We developed the assay using phage Mu transposition as a test model and validated the platform using various MuA transposase mutants. For further validation and to illustrate universality, we introduced IS903 transposition system components into the assay. The developed assay is adjustable to a desired level of initial transposition via the control of a plasmid-borne E. coli arabinose promoter. In practice, the transposition frequency is modulated by varying the concentration of arabinose or glucose in the growth medium. We show that variable levels of transpositional activity can be analysed, thus enabling straightforward screens for hyper- or hypoactive transposase mutants, regardless of the original wild-type activity level. Conclusions The established universal papillation assay platform should be widely applicable to a variety of mobile elements. It can be used for mechanistic studies to dissect transposition and provides a means to screen or scrutinise transposase mutants and genes encoding host factors. In succession, improved versions of transposition systems should yield better tools for molecular biology and offer versatile genome modification vehicles for many types of studies, including gene therapy and stem cell research.

2010-01-01

206

Aqua-Sim: An NS2 based simulator for underwater sensor networks  

Microsoft Academic Search

In this paper, we present a network simulator, Aqua-Sim, for underwater sensor networks. Aqua-Sim is based on NS-2, one of the most widely used network simulators, and it follows object-oriented design style and all network entities are implemented as classes. Aqua-Sim effectively simulates the attenuation of underwater acoustic channels and the collision behaviors in long delay acoustic networks. Moreover, Aqua-Sim

Peng Xie; Zhong Zhou; Zheng Peng; Hai Yan; Tiansi Hu; Jun-Hong Cui; Zhijie Shi; Yunsi Fei; Shengli Zhou

2009-01-01

207

Atmospheric Gravity Wave Processes from Aqua Measurements  

NASA Astrophysics Data System (ADS)

Although not originally designed for this purpose, the high spatial resolution of AIRS and AMSU measurements have revealed new details of small-scale atmospheric gravity waves and their many effects on climate processes during the last decade. Gravity waves themselves drive localized temperature fluctuations with important impacts on clouds, precipitation, and atmospheric chemistry. Drag forces associated with gravity wave breaking drive circulation changes in climate models with additional wide-ranging effects. Models used for global weather forecasting now resolve some gravity wave features with scales of several hundred km, but many other gravity waves remain unresolved, while climate models resolve only some of the largest scale gravity waves. Understanding these waves, how they are generated, and how their climate effects can be best parameterized have become important issues both for testing current models and improving next generation climate predictions. Our research focuses both on waves from convection and mountain waves. AIRS radiance measurements provide the highest resolution, and we use these data to quantify wave generation by small mountainous islands and the effects of these waves on the general circulation. We also estimate the relative importance of the smallest-resolvable versus larger-scale mountain waves to the circulation directly from AIRS measurements. Details of wave generation within convective clouds are also examined, where AIRS measurements provide the constraints for simulations of their generation and propagation. These studies allow us to test assumptions employed in current parameterization methods. We will also show how the local-time sampling of Aqua is an important limitation for studies of gravity waves generated by convection.

Alexander, M.; Eckermann, S. D.; Grimsdell, A.; Hoffmann, L.; Teitelbaum, H.

2011-12-01

208

A new quantitative method for gunshot residue analysis by ion beam analysis.  

PubMed

Imaging and analyzing gunshot residue (GSR) particles using the scanning electron microscope equipped with an energy dispersive X-ray spectrometer (SEM-EDS) is a standard technique that can provide important forensic evidence, but the discrimination power of this technique is limited due to low sensitivity to trace elements and difficulties in obtaining quantitative results from small particles. A new, faster method using a scanning proton microbeam and Particle Induced X-ray Emission (?-PIXE), together with Elastic Backscattering Spectrometry (EBS) is presented for the non-destructive, quantitative analysis of the elemental composition of single GSR particles. In this study, the GSR particles were all Pb, Ba, Sb. The precision of the method is assessed. The grouping behaviour of different makes of ammunition is determined using multivariate analysis. The protocol correctly groups the cartridges studied here, with a confidence >99%, irrespective of the firearm or population of particles selected. PMID:23775063

Christopher, Matthew E; Warmenhoeven, John-William; Romolo, Francesco S; Donghi, Matteo; Webb, Roger P; Jeynes, Christopher; Ward, Neil I; Kirkby, Karen J; Bailey, Melanie J

2013-06-18

209

Quantitative analysis of localized surface plasmons based on molecular probing.  

PubMed

We report on the quantitative characterization of the plasmonic optical near-field of a single silver nanoparticle. Our approach relies on nanoscale molecular molding of the confined electromagnetic field by photoactivated molecules. We were able to directly image the dipolar profile of the near-field distribution with a resolution better than 10 nm and to quantify the near-field depth and its enhancement factor. A single nanoparticle spectral signature was also assessed. This quantitative characterization constitutes a prerequisite for developing nanophotonic applications. PMID:20687536

Deeb, Claire; Bachelot, Renaud; Plain, Jérôme; Baudrion, Anne-Laure; Jradi, Safi; Bouhelier, Alexandre; Soppera, Olivier; Jain, Prashant K; Huang, Libai; Ecoffet, Carole; Balan, Lavinia; Royer, Pascal

2010-08-24

210

Quantitative Analysis of Autophagy using Advanced 3D Fluorescence Microscopy.  

PubMed

Prostate cancer is the leading form of malignancies among men in the U.S. While surgery carries a significant risk of impotence and incontinence, traditional chemotherapeutic approaches have been largely unsuccessful. Hormone therapy is effective at early stage, but often fails with the eventual development of hormone-refractory tumors. We have been interested in developing therapeutics targeting specific metabolic deficiency of tumor cells. We recently showed that prostate tumor cells specifically lack an enzyme (argininosuccinate synthase, or ASS) involved in the synthesis of the amino acid arginine(1). This condition causes the tumor cells to become dependent on exogenous arginine, and they undergo metabolic stress when free arginine is depleted by arginine deiminase (ADI)(1,10). Indeed, we have shown that human prostate cancer cells CWR22Rv1 are effectively killed by ADI with caspase-independent apoptosis and aggressive autophagy (or macroautophagy)(1,2,3). Autophagy is an evolutionarily-conserved process that allows cells to metabolize unwanted proteins by lysosomal breakdown during nutritional starvation(4,5). Although the essential components of this pathway are well-characterized(6,7,8,9), many aspects of the molecular mechanism are still unclear - in particular, what is the role of autophagy in the death-response of prostate cancer cells after ADI treatment? In order to address this question, we required an experimental method to measure the level and extent of autophagic response in cells - and since there are no known molecular markers that can accurately track this process, we chose to develop an imaging-based approach, using quantitative 3D fluorescence microscopy(11,12). Using CWR22Rv1 cells specifically-labeled with fluorescent probes for autophagosomes and lysosomes, we show that 3D image stacks acquired with either widefield deconvolution microscopy (and later, with super-resolution, structured-illumination microscopy) can clearly capture the early stages of autophagy induction. With commercially available digital image analysis applications, we can readily obtain statistical information about autophagosome and lysosome number, size, distribution, and degree of colocalization from any imaged cell. This information allows us to precisely track the progress of autophagy in living cells and enables our continued investigation into the role of autophagy in cancer chemotherapy. PMID:23665532

Changou, Chun A; Wolfson, Deanna L; Ahluwalia, Balpreet Singh; Bold, Richard J; Kung, Hsing-Jien; Chuang, Frank Y S

2013-05-03

211

Quantitative analysis of ?? precipitation kinetics in Al–Li alloys  

Microsoft Academic Search

The Rietveld method has been applied to X-ray spectra in order to study the precipitated mass fraction of ?? and ? in Al–Li alloys. The method allows us to obtain quantitatively the ?? and ? precipitate mass fractions, and their evolution with aging time. Furthermore, this method also gives directly the cell parameter evolution of the matrix phase and indirectly

J. I. Perez-Landazabal; M. L. No; G. Madariaga; V. Recarte

2000-01-01

212

Quantitative analysis of pyrolytic carbon films by polarized light microscopy  

Microsoft Academic Search

The optical properties of differently textured pyrolytic carbon films were quantitatively analyzed by polarized light microscopy. The light intensity for the investigation of optically anisotropic and birefringent materials by polarized light microscopy was calculated as a function of the analyzer angle and the orientation of the material. From these calculations the dependence of the extinction angle on the optical properties

Andreas Pfrang; Thomas Schimmel

2004-01-01

213

Quantitative Mineralogical Analysis by X-ray diffraction.  

National Technical Information Service (NTIS)

Work was done in two phases on different combinations of soil-like crystalline materials that were mixed in the laboratory to develop a simple, rapid, and inexpensive method of doing quantitative mineralogical analyses, largely by X-ray diffraction (XRD)....

A. D. Buck

1972-01-01

214

Quantitative XRD analysis of zirconia-toughened alumina ceramics  

Microsoft Academic Search

An equation is proposed to give, from XRD data, the tetragonal to monoclinic phase ratio of zirconia in a toughened alumina ceramic material. Using several X-ray wavelengths, with different depths of penetration, quantitative analyses of the tetragonal to monoclinic phase ratio of zirconia as a function of depth were performed, on an as-sintered sample as well as on treated specimens.

R. Fillit; R. P. Homerin; R. J. Schafer; R. H. Bruyas; R. F. Thevenot

1987-01-01

215

Ethnicity and body image: Quantitative and qualitative analysis  

Microsoft Academic Search

Objective: Cultural diversity in body image has been studied elsewhere. In this study, we extend previous research by inclusion of (1) multiple ethnic groups for comparison and (2) measures for the assessment of multiple dimensions of body image. Method: Partici- pants were college students who self-identified as African, Asian, Caucasian, or Hispanic- American. Quantitative measures of weight-related body image and

Madeline Altabe

1998-01-01

216

Quantitative analysis of alternate oil spill response strategies using OSCAR  

Microsoft Academic Search

A three-dimensional numerical model of the physical and chemical behavior and fate of spilled oil has been coupled to a model of oil spill response actions. This coupled system of models for Oil Spill Contingency and Response (OSCAR), provides a tool for quantitative, objective assessment of alternative oil spill response strategies. Criteria for response effectiveness can be either physical (‘How

Mark Reed; Ole Morten Aamo; Per S. Daling

1995-01-01

217

Problems in quantitative analysis of five steroid hormones by HPLC  

Microsoft Academic Search

To get a good separation of all 5 hormones, we were forced to add tetrahydrofuran to the mobile phase. At 214 nm this contributes to a higher detection limit. Measurement at 214 nm is necessary for the detection of dehydroepiandrosterone and dihydrotestosterone. Another limiting factor of the quantitative estimation of integration are increasing contaminations after extraction, when using larger amounts

Marina Baumeister; G. K. Stalla; O. A. Müller

1984-01-01

218

Quantitative analysis techniques for instability flow experiments and computations  

Microsoft Academic Search

We quantitatively compare images of a Richtmyer-Meshkov (RM) unstable gas curtain flow produced both experimentally as well as computationally as the flow transitions to turbulence. The RM instability is in many ways an ideal way to study the transition to turbulence caused by instability flows. In our study, a thin curtain of heavy gas (SF6 in air) is accelerated impulsively

Paul Rightley; Peter Vorobieff; Jim Kamm; William Rider; Joyce Guzik; Ryan Martin; Robert Benjamin

1998-01-01

219

Microcomputer-based digital image analysis system for quantitative autoradiography  

Microsoft Academic Search

A computerized image processing system utilizing an IBM-XT personal microcomputer with the capability of performing quantitative cerebral autoradiography is described. All of the system components are standard computer and optical hardware that can be easily assembled. The system has 512 horizontal by 512 vertical axis resolution with 8 bits per pixel (256 gray levels). Unlike other dedicated image processing systems,

T. J. Hoffman; W. A. Volkert; R. A. Holmes

1988-01-01

220

Quantitative Trait Locus Analysis of the Early Domestication of Sunflower  

Microsoft Academic Search

Genetic analyses of the domestication syndrome have revealed that domestication-related traits typically have a very similar genetic architecture across most crops, being conditioned by a small number of quantitative trait loci (QTL), each with a relatively large effect on the phenotype. To date, the domes- tication of sunflower (Helianthus annuus L.) stands as the only counterexample to this pattern. In

David M. Wills; John M. Burke

2007-01-01

221

Quantitative Analysis of Radionuclides in Process and Environmental Samples  

SciTech Connect

An analytical method was developed for the radiochemical separation and quantitative recovery of ruthenium, zirconium, niobium, neptunium, cobalt, iron, zinc, strontium, rare earths, chromium and cesium from a wide variety of natural materials. This paper discusses this analytical method, based on the anion exchange properties of the various radionuclides, although both ion exchange and precipitation techniques are incorporated.

Boni, A.L.

2003-02-21

222

Children's Overregularization of English Plurals: A Quantitative Analysis.  

ERIC Educational Resources Information Center

Presents a quantitative study of children's noun plural overregularizations on recent comparisons of connectionist and symbolic models of language. The speech of 10 English-speaking children aged 1;3 to 5;2 were analyzed. Results pose challenges to connectionist models, but are consistent with the blocking-and-retrieval-failure model in which…

Marcus, Gary F.

1995-01-01

223

Convergence in problem solving: a prelude to quantitative analysis  

Microsoft Academic Search

The paper describes a set of procedures that could be successfully used to restructure a mental model of diverse, connected constructs into a compact model suitable for quantitatively examining the key options available to the decision maker. These procedures can be applied in an interactive manner with a single decision maker or group of decision makers. The input to the

Dennis M. Buede; D. O. Ferrell

1993-01-01

224

Quantitative Analysis of Central Metabolic Pathway For Modeling and Simulation  

Microsoft Academic Search

Towards modeling and simulation, Glycolysis and TCA cycle pathways of E. coli were quantitatively analyzed in transcription, enzymes and metabolites levels during cell growth in MOPS medium with 0.4% of glucose. To measure enzyme copy number in vivo and in a single cell manner, we developed chromosomal fusion construct of about 100 central metabolic pathway related enzyme genes including some

Hirotada Mori; Hitomi Dose; Yuto Ikegami; Tomoaki Yamamotoya; Barry L. Wanner; Hirosi Matsuno

225

Quantitative analysis and parametric display of regional myocardial mechanics  

Microsoft Academic Search

Quantitative assessment of regional heart motion has significant potential for more accurate diagnosis of heart disease and\\/or cardiac irregularities. Local heart motion may be studied from medical imaging sequences. Using functional parametric mapping, regional myocardial motion during a cardiac cycle can be color mapped onto a deformable heart model to obtain better understanding of the structure- to-function relationships in the

Christian D. Eusemann; Matthias E. Bellemann; Richard A. Robb

2000-01-01

226

Quantitative Analysis and Parametric Display of Regional Myocardial Mechanics  

Microsoft Academic Search

Quantitative assessment of regional heart motion has significant potential for more accurate diagnosis of heart disease and \\/ or cardiac irregularities. Local heart motion may be studied from medical imaging sequences. Using functional parametric mapping, regional myocardial motion during a cardiac cycle can be color mapped onto a deformable heart model to obtain better understanding of the structure-to-function relationships in

Christian. D. Eusemann; Matthias E. Bellemann; Richard A. Robb; B Tatzendpromenade

227

Quantitative and Qualitative Analysis of Biomarkers in Fusarium verticillioides  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study, a combination HPLC-DART-TOF-MS system was utilized to identify and quantitatively analyze carbohydrates in wild type and mutant strains of Fusarium verticillioides. Carbohydrate fractions were isolated from F. verticillioides cellular extracts by HPLC using a cation-exchange size-excl...

228

A quantitative analysis of computed hypervelocity debris clouds  

Microsoft Academic Search

This paper presents quantitative analyses of computed hypervelocity debris clouds due to aluminum spheres, rods and disks impacting aluminum bumper plates. The computations were performed using an algorithm to convert distorted Lagrangian finite elements to meshfree particles. The analyses were performed using a new postprocessing algorithm. The combination of this computational approach and this postprocessing algorithm is also used to

S. R. Beissel; C. A. Gerlach; G. R. Johnson

2008-01-01

229

Quantitative Analysis of Radionuclides in Process and Environmental Samples  

Microsoft Academic Search

An analytical method was developed for the radiochemical separation and quantitative recovery of ruthenium, zirconium, niobium, neptunium, cobalt, iron, zinc, strontium, rare earths, chromium and cesium from a wide variety of natural materials. This paper discusses this analytical method, based on the anion exchange properties of the various radionuclides, although both ion exchange and precipitation techniques are incorporated.

Boni

2003-01-01

230

QUANTITATIVE ANALYSIS OF RADIONUCLIDES IN PROCESS AND ENVIRONMENTAL SAMPLES  

Microsoft Academic Search

An analytical method is developed for the radiochemical separation and ; quantitative recovery of ruthenium, zirconium, niobium, neptunium, cobalt. iron, ; zinc, strontium, rare earths. chromium, and cesium from a wide variety of natural ; materials. The method is based on the anion exchange properties of the various ; radionuclides, although both ion exchange and precipitatlon techniques are ; incorporated.

A. L. Boni

1960-01-01

231

Labor Market Policies and Unemployment in Morocco: A Quantitative Analysis  

Microsoft Academic Search

Ag?nor and El Aynaoui study the impact of labor market policies on unemployment in Morocco. They begin by reviewing the main features of the labor market. Then they present a quantitative framework that captures many of these features?such as a large public sector, high redundancy payments, powerful trade unions, and international labor migration. The authors simulate the impact of a

Karim El Aynaoui

2003-01-01

232

MOLD SPECIFIC QUANTITATIVE PCR: THE EMERGING STANDARD IN MOLD ANALYSIS  

EPA Science Inventory

Today I will talk about the use of quantitative or Real time PCR for the standardized identification and quantification of molds. There are probably at least 100,000 species of molds or fungi. But there are actually about 100 typically found indoors. Some pose a threat to human...

233

Depression in Parkinson's disease: a quantitative and qualitative analysis  

Microsoft Academic Search

Depression is a common feature of Parkinson's disease, a fact of both clinical and theoretical significance. Assessment of depression in Parkinson's disease is complicated by overlapping symptomatology in the two conditions, making global assessments based on observer or self-ratings of doubtful validity. The present study aimed to provide both a quantitative and qualitative description of the nature of the depressive

A M Gotham; R G Brown; C D Marsden

1986-01-01

234

Quantitative analysis of the density and pattern of adrenergic innervation of blood vessels  

Microsoft Academic Search

Automated quantitative image analysis (QIAF) was used to measure and compare the adrenergic nerve plexuses of 4 blood vessels from the guinea pig, demonstrated by glyoxylic acid fluorescence (GAF). The results showed considerable quantitative variation of plexus density, size of bundles, and numbers of varicosities. A range of alternative procedural and anatomical sources of variability were investigated and assessed. The

T. Cowen; G. Burnstock

1980-01-01

235

Augmented vessels for quantitative analysis of vascular abnormalities and endovascular treatment planning  

Microsoft Academic Search

Endovascular treatment plays an important role in the minimally invasive treatment of patients with vascular diseases, a major cause of morbidity and mortality worldwide. Given a segmentation of an angiography, quantitative analysis of abnormal structures can aid radiologists in choosing appropriate treatments and apparatuses. However, effective quantitation is only attainable if the abnormalities are identified from the vasculature. To achieve

Wilbur C. K. Wong; Albert C. S. Chung

2006-01-01

236

An Inexpensive Electrodeposition Device and Its Use in a Quantitative Analysis Laboratory Exercise  

ERIC Educational Resources Information Center

An experimental procedure, using an apparatus that is easy to construct, was developed to incorporate a quantitative electrogravimetric determination of the solution nickel content into an undergraduate or advanced high school quantitative analysis laboratory. This procedure produces results comparable to the procedure used for the gravimetric…

Parker, Richard H.

2011-01-01

237

An Inexpensive Electrodeposition Device and Its Use in a Quantitative Analysis Laboratory Exercise  

ERIC Educational Resources Information Center

|An experimental procedure, using an apparatus that is easy to construct, was developed to incorporate a quantitative electrogravimetric determination of the solution nickel content into an undergraduate or advanced high school quantitative analysis laboratory. This procedure produces results comparable to the procedure used for the gravimetric…

Parker, Richard H.

2011-01-01

238

Colorimetric Assays for Quantitative Analysis and Screening of Epoxide Hydrolase Activity  

Microsoft Academic Search

Focusing on directed evolution to tailor enzymes as usable biocatalysts for fine chemistry, we have studied in detail several colorimetric assays for quantitative analysis of epoxide hydrolase (EH) activity. In particular, two assays have been optimized to characterize variants issued from the directed evolution of the EH from Aspergillus niger. Assays described in this paper are sufficiently reliable for quantitative

F. Cedrone; T. Bhatnagar; Jacques C. Baratti

2005-01-01

239

An integrated approach of quantitative and qualitative analysis in the study of identity in speeches  

Microsoft Academic Search

Identity is usually analysed by focusing on a single case and scrutinizing relevant text fragments. This approach rules out the possibility of doing research on larger corpora, such as my corpus of 40 speeches. To this end, an integrated approach of both quantitative and qualitative analysis is proposed here. For the quantitative method, pronouns were selected as markers of the

Dorien Van De Mieroop

2005-01-01

240

A quantitative analysis of sodium transport and removal during peritoneal dialysis  

Microsoft Academic Search

A quantitative analysis of sodium transport and removal during peritoneal dialysis. To quantitatively evaluate peritoneal sodium transport, the diffusive mass transport coefficient (KBD) and sieving coefficient (S), as well as the mass of sodium transported by diffusion (DM), by convection (CM) and by fluid absorption (AM) and the total sodium mass removed (RM) were calculated during a series of single

Tao Wang; Jacek Waniewski; Olof Heimbürger; Andrzej Werynski; Bengt Lindholm

1997-01-01

241

New anabaenopeptins, potent carboxypeptidase-A inhibitors from the cyanobacterium Aphanizomenon flos-aquae.  

PubMed

Anabaenopeptins I (1) and J (2), two new ureido bond-containing cyclic peptides, were isolated from the cultured cyanobacterium Aphanizomenon flos-aquae (NIES-81) as potent carboxypeptidase-A (CPA) inhibitors. The gross structures of 1 and 2 were established by spectroscopic analysis, including the 2D NMR techniques. The absolute configurations of 1 and 2 were determined by spectral and chemical methods. Anabaenopeptins I and J inhibited CPA with IC(50) values of 5.2 and 7.6 ng/mL, respectively. PMID:11000037

Murakami, M; Suzuki, S; Itou, Y; Kodani, S; Ishida, K

2000-09-01

242

Quantitative analysis of microchimerism in systemic sclerosis skin tissue  

Microsoft Academic Search

\\u000a Abstract It has been reported that more male DNA of presumed fetal origin is present in the blood and skin of women with systemic\\u000a sclerosis (SSc) as compared with healthy controls after delivery, but these findings are controversial. We sought to determine\\u000a whether male cell DNA is present in SSc using a quantitative polymerase chain reaction for Y chromosome DNA.

Tsutomu Ohtsuka; Yukari Miyamoto; Akio Yamakage; Soji Yamazaki

2001-01-01

243

Detection of Quantitative Trait Associated Genes Using Cluster Analysis  

Microsoft Academic Search

Many efforts have been involved in association study of quantitative phenotypes and expressed genes. The key issue is how\\u000a to efficiently identify phenotype-associated genes using appropriate methods. The limitations for the existing approaches\\u000a are discussed. We propose a hierarchical mixture model in which the relationship between gene expressions and phenotypic values\\u000a is described using orthogonal polynomials. Gene specific coefficient, which

Zhenyu Jia; Sha Tang; Dan Mercola; Shizhong Xu

2008-01-01

244

Quantitative spectroscopy analysis of prokaryotic cells: vegetative cells and spores.  

PubMed

Multiwavelength ultraviolet/visible (UV-Vis) spectra of microorganisms and cell suspensions contain quantitative information on properties such as number, size, shape, chemical composition, and internal structure of the suspended particles. These properties are essential for the identification and classification of microorganisms and cells. The complexity of microorganisms in terms of their chemical composition and internal structure make the interpretation of their spectral signature a difficult task. In this paper, a model is proposed for the quantitative interpretation of spectral patterns resulting from transmission measurements of prokaryotic microorganism suspensions. It is also demonstrated that different organisms give rise to spectral differences that may be used for their identification and classification. The proposed interpretation model is based on light scattering theory, spectral deconvolution techniques, and on the approximation of the frequency dependent optical properties of the basic constituents of living organisms. The quantitative deconvolution in terms of the interpretation model yields critical information necessary for the detection and identification of microorganisms, such as size, dry mass, dipicolinic acid concentration, nucleotide concentration, and an average representation of the internal scattering elements of the organisms. E. coli, P. agglomerans, B. subtilis spores, and vegetative cells and spores of Bacillus globigii are used as case studies. It is concluded that spectroscopy techniques coupled with effective interpretation models are applicable to a wide range of cell types found in diverse environments. PMID:15128109

Alupoaei, Catalina E; Olivares, Jose A; García-Rubio, Luis H

2004-03-15

245

Evaluation of mRNA by Q-RTPCR and Protein Expression by AQUA of the M2 Subunit of Ribonucleotide Reductase (RRM2) in Human Tumors  

PubMed Central

Purpose The purpose of this study was to evaluate baseline RRM2 protein and gene expression in tumors of patients receiving 3-AP. Experimental Design Tumor blocks from patients enrolled in phase I and II clinical studies using 3-AP, were evaluated for RRM2 gene and protein expression by quantitative real time polymerase chain reaction (Q-RTPCR) and automated quantitative analysis, (AQUA). Results Esophageal and gastric cancers overexpressed RRM2 protein when compared to prostate cancer (Z-score, 0.68 ± 0.94 SD, vs 0.41 ± 0.84SD, respectively,; p=0.04). Esophageal and gastric cancers also overexpressed RRM2 mRNA when compared to prostate cancer (relative gene expression 2.56 ± 1.49 SD, vs 0.29 ± 0.20 SD, respectively,; p=0.02). Protein and gene expression were moderately associated (Spearman's rank correlation =0.30; p=0.12). Conclusion RRM2 gene and protein expression varies by tumor type and may predict response to 3-AP.

Kolesar, Jill; Huang, Wei; Eickhoff, Jens; Hahn, Kristine; Alberti, Dona; Attia, Steve; Schelman, William; Holen, Kyle; Traynor, Anne; Ivy, Percy; Wilding, George

2011-01-01

246

Matrix effects in quantitative pesticide analysis using liquid chromatography-mass spectrometry.  

PubMed

Combined liquid chromatography-mass spectrometry using electrospray or atmospheric-pressure chemical ionization has become an important tool in the quantitative analysis of pesticide residues in various matrices in relation to environmental analysis, food safety, and biological exposure monitoring. One of the major problems in the quantitative analysis using LC-MS is that compound and matrix-dependent response suppression or enhancement may occur, the so-called matrix effect. This article reviews issues related to matrix effects, focusing on quantitative pesticide analysis, but also paying attention to expertise with respect to matrix effects acquired in other application areas of LC-MS, especially quantitative bioanalysis in the course of drug development. PMID:16783795

Niessen, W M A; Manini, P; Andreoli, R

247

Global Quantitative Analysis of Operon/Gene Transcription in Bacillus Anthracis During Experimental Infection.  

National Technical Information Service (NTIS)

The objective is to perform the first comprehensive quantitative analysis of Bacillus anthracis operon/gene transcription during in viva experimental infection to enable the identification of additional virulence factors, potential vaccine candidates, and...

M. Gwynn D. McDevitt

2003-01-01

248

Cognitive rehabilitation in schizophrenia: a quantitative analysis of controlled studies  

Microsoft Academic Search

Rationale  Cognitive rehabilitation is now recognized as an important tool in the treatment of schizophrenia, and findings in this area\\u000a are emerging rapidly. There is a need for a systematic review of the effects of the different training programs.\\u000a \\u000a \\u000a \\u000a Objectives  To review quantitatively the controlled studies on cognitive rehabilitation in schizophrenia for the effect of training on\\u000a performance on tasks other than

Lydia Krabbendam; André Aleman

2003-01-01

249

Optimal climate policy is a utopia: from quantitative to qualitative cost-benefit analysis  

Microsoft Academic Search

The dominance of quantitative cost-benefit analysis (CBA) and optimality concepts in the economic analysis of climate policy is criticised. Among others, it is argued to be based in a misplaced interpretation of policy for a complex climate–economy system as being analogous to individual inter-temporal welfare optimisation. The transfer of quantitative CBA and optimality concepts reflects an overly ambitious approach that

2004-01-01

250

Significance analysis of microarray for relative quantitation of LC\\/MS data in proteomics  

Microsoft Academic Search

BACKGROUND: Although fold change is a commonly used criterion in quantitative proteomics for differentiating regulated proteins, it does not provide an estimation of false positive and false negative rates that is often desirable in a large-scale quantitative proteomic analysis. We explore the possibility of applying the Significance Analysis of Microarray (SAM) method (PNAS 98:5116-5121) to a differential proteomics problem of

Bryan A. P. Roxas; Qingbo Li

2008-01-01

251

Automated morphometric analysis of coronary artery lesions: an extension of quantitative coronary arteriography  

Microsoft Academic Search

The authors describe an extension to standard quantitative coronary artery analysis which provides automated objective quantitative evaluation of morphologic features of coronary-artery lesions. Standard edge detection has been enhanced with a sequential edge-linking algorithm to provide increased spatial sampling of arterial borders. These edges are analyzed using previously developed shape-analysis techniques. Morphometric parameters describing edge features such as the presence

S. B. Simon; M. T. LeFree; M. J. McGillem; S. J. Kalbfleisch; E. G. Anselmo; J. Sitomer; S. F. DeBoe; S. Ellis; G. B. J. Mancini

1988-01-01

252

Plural Analysis: Developing Multiple Approaches to Quantitative Research. Phase 1.  

National Technical Information Service (NTIS)

The project proposes a methodology of plural analysis, with a decision-science focus, which is to be grounded in sound science and be practically useful. The methodology comprises guidelines and computer aids for conducting plural analysis and methods for...

R. V. Brown D. V. Lindley J. W. Ulvila D. V. Winterfeldt

1984-01-01

253

Quantitative analysis of biopolymers by matrix-assisted laser desorption  

SciTech Connect

During the past few years, major efforts have been made to use mass spectrometry to measure biopolymers because of the great potential benefit to biological and medical research. Although the theoretical details of laser desorption and ionization mechanisms of MALDI are not yet fully understood, several models have been presented to explain the production of large biopolymer ions. In brief, it is very difficult to obtain reliable measurements of the absolute quantity of analytes by MALDI. If MALDI is going to become a routine analytical tool, it is obvious that quantitative measurement capability must be pursued. Oligonucleotides and protein samples used in this work were purchased from commercial sources. Nicotinic acid was used as matrix for both types of biopolymers. From this experiment, it is seen that it is difficult to obtain absolute quantitative measurements of biopolymers using MALDI. However, internal calibration with molecules having similar chemical properties can be used to resolve these difficulties. Chemical reactions between biopolymers must be avoided to prevent the destruction of the analyte materials. 10 refs., 8 figs.

Tang, K.; Allman, S.L.; Jones, R.B.; Chen, C.H. (Oak Ridge National Lab., TN (United States))

1993-08-01

254

Quantitative analysis of radiation-induced changes in sperm morphology  

SciTech Connect

When developing spermatogenic cells are exposed to radiation, chemical carcinogens or mutagens, the transformation in the morphology of the mature sperm can be used to determine the severity of the exposure. In this study five groups of mice with three mice per group received testicular doses of X irradiation at dosage levels ranging from 0 rad to 120 rad. A random sample of 100 mature sperm per mouse was analyzed five weeks later for the quantitative morphologic transformation as a function of dosage level. The cells were stained with gallocyanin chrome alum (GCA) so that only the DNA in the sperm head was visible. The ACUity quantitative microscopy system at Lawrence Livermore National Laboratory was used to scan the sperm at a sampling density of 16 points per linear micrometer and with 256 brightness levels per point. The contour of each cell was extracted using conventional thresholding techniques on the high-contrast images. For each contour a variety of shape features was then computed to characterize the morphology of that cell. Using the control group and the distribution of their shape features to establish the variability of a normal sperm population, the 95% limits on normal morphology were established. Using only four shape features, a doubling dose of approximately 39 rad was determined. That is, at 39 rad exposure the percentage of abnormal cells was twice that occurring in the control population. This compared to a doubling dose of approximately 70 rad obtained from a concurrent visual procedure.

Young, I.T.; Gledhill, B.L.; Lake, S.; Wyrobek, A.J.

1982-09-01

255

iTRAQ-based quantitative secretome analysis of Phanerochaete chrysosporium.  

PubMed

The basidiomycete fungi such as Phanerochaete chrysosporium secrete large amount of hydrolytic and oxidative enzymes and degrade lignocellulosic biomass. The lignin depolymerizing proteins were extensively studied, but cellulose, hemicellulose and pectin hydrolyzing enzymes were poorly explored. In this study P. chrysosporium was grown in cellulose, lignin and mixture of cellulose and lignin, and secretory proteins were quantified by isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics using liquid chromatography tandem mass spectrometry (LC-MS/MS). An iTRAQ quantified 117 enzymes comprising cellulose hydrolyzing endoglucanases, exoglucanases, beta-glucosidases; hemicelluloses hydrolyzing xylanases, acetylxylan esterases, mannosidases, mannanases; pectin-degrading enzymes polygalacturonase, rhamnogalacturonase, arabinose and lignin degrading protein belonging to oxidoreductase family. Under cellulose and cellulose with lignin culture conditions, enzymes such as endoglucanases, exoglucanases, ?-glucosidases and cellobiose dehydrogenase were significantly upregulated and iTRAQ data suggested hydrolytic and oxidative cellulose degradation. When lignin was used as a major carbon source, enzymes such as copper radical oxidase, isoamyl oxidase, glutathione S-transferase, thioredoxin peroxidase, quinone oxidoreductase, aryl alcohol oxidase, pyranose 2-oxidase, aldehyde dehydrogenase, and alcohol dehydrogenase were expressed and significantly regulated. This study explored cellulose, hemicellulose, pectin and lignin degrading enzymes of P. chrysosporium that are valuable for lignocellulosic bioenergy. PMID:21945728

Manavalan, Arulmani; Adav, Sunil S; Sze, Siu Kwan

2011-09-13

256

Quantitative Raman Spectroscopy for the Analysis of Carrot Bioactives.  

PubMed

Rapid quantitative near-infrared Fourier transform Raman analyses of the key phytonutrients in carrots, polyacetylenes and carotenoids, are reported here for the first time. Solvent extracts of 31 carrot lines were analyzed for these phytonutrients by conventional methods, polyacetylenes by GC-FID and carotenoids by visible spectrophotometry. Carotenoid concentrations were 0-5586 ?g g(-1) dry weight (DW). Polyacetylene concentrations were 74-4846 ?g g(-1) DW, highest in wild carrots. The polyacetylenes were falcarinol, 6-1237 ?g g(-1) DW; falcarindiol, 42-3475 ?g g(-1) DW; and falcarindiol 3-acetate, 27-649 ?g g(-1) DW. Strong Raman bands for carotenoids gave good correlation to results by visible spectrophotometry. A chemometric model capable of quantitating carotenoids from Raman data was developed. A classification model for rapidly distinguishing carrots with high and low polyacetylene (limit of detection = 1400 ?g g(-1)) concentrations based on Raman spectral intensity in the region of 2250 cm(-1) was produced. PMID:23441972

Killeen, Daniel P; Sansom, Catherine E; Lill, Ross E; Eason, Jocelyn R; Gordon, Keith C; Perry, Nigel B

2013-03-11

257

Quantitative Spectral Analysis of Evolved Low-Mass Stars  

NASA Astrophysics Data System (ADS)

The hydrogen-deficiency in extremely hot post-AGB stars of spectral class PG1159 is probably caused by a (very) late helium-shell flash or a AGB final thermal pulse that consumes the hydrogen envelope, exposing the usually-hidden intershell region. Thus, the photospheric element abundances of these stars allow us to draw conclusions about details of nuclear burning and mixing processes in the precursor AGB stars. We compare predicted element abundances to those determined by quantitative spectral analyses performed with advanced non-LTE model atmospheres. A good qualitative and quantitative agreement is found for many species (He, C, N, O, Ne, F, Si, Ar) but discrepancies for others (P, S, Fe) point at shortcomings in stellar evolution models for AGB stars. Almost all of the chemical trace elements in these hot stars can only be identified in the UV spectral range. The Far Ultraviolet Spectroscopic Explorer and the Hubble Space Telescope played a crucial role for this research.

Werner, Klaus; Rauch, Thomas; Kruk, Jeffrey W.

2009-09-01

258

Qualitative and quantitative analysis of volatile constituents from latrines.  

PubMed

More than 2.5 billion people defecate in the open. The increased commitment of private and public organizations to improving this situation is driving the research and development of new technologies for toilets and latrines. Although key technical aspects are considered by researchers when designing new technologies for developing countries, the basic aspect of offending malodors from human waste is often neglected. With the objective of contributing to technical solutions that are acceptable to global consumers, we investigated the chemical composition of latrine malodors sampled in Africa and India. Field latrines in four countries were evaluated olfactively and the odors qualitatively and quantitatively characterized with three analytical techniques. Sulfur compounds including H2S, methyl mercaptan, and dimethyl-mono-(di;tri) sulfide are important in sewage-like odors of pit latrines under anaerobic conditions. Under aerobic conditions, in Nairobi for example, paracresol and indole reached concentrations of 89 and 65 ?g/g, respectively, which, along with short chain fatty acids such as butyric acid (13 mg/g) explained the strong rancid, manure and farm yard odor. This work represents the first qualitative and quantitative study of volatile compounds sampled from seven pit latrines in a variety of geographic, technical, and economic contexts in addition to three single stools from India and a pit latrine model system. PMID:23829328

Lin, Jianming; Aoll, Jackline; Niclass, Yvan; Velazco, Maria Inés; Wünsche, Laurent; Pika, Jana; Starkenmann, Christian

2013-07-05

259

Direct evidence for the role of light-mediated gas vesicle collapse in the buoyancy regulation of Anabaena flos-aquae (cyanobacteria)  

Microsoft Academic Search

Quantitative measurements were made of the changes in gas vacuole volume and the major components of cell mass (protein and carbohydrate) on cultures of Anabaenaflos-aquae which lost buoyancy as they were shifted from low to high light intensity. Assuming densities of 1,300 kg. rn-' for protein and 1,600 for carbohydrate, we calculated the change in ballast brought about by changes

R. L. OLIVER; A. E. WAISBY

1984-01-01

260

Quantitative analysis of Plasmodium berghei liver stages by bioluminescence imaging.  

PubMed

We describe simple and sensitive in vitro and in vivo assays to analyze Plasmodium liver stage development using transgenic P. berghei parasites (PbGFP-Luccon), which express the bioluminescent reporter protein, luciferase. In these assays, parasite development in hepatocytes is visualized and quantified by real-time bioluminescence imaging both in culture and in live mice. We also describe quantification of in vitro liver-stage development by measuring luminescence using a microplate reader. Reporter-parasite based quantification of liver-stage development is faster and correlates very well with established quantitative RT-PCR methods currently used to assess parasite development inside hepatocytes, both in live mice and in culture. PMID:22990796

Annoura, Takeshi; Chevalley, Séverine; Janse, Chris J; Franke-Fayard, Blandine; Khan, Shahid M

2013-01-01

261

Empirical research in bioethical journals. A quantitative analysis  

PubMed Central

Objectives The objective of this research is to analyse the evolution and nature of published empirical research in the fields of medical ethics and bioethics. Design Retrospective quantitative study of nine peer reviewed journals in the field of bioethics and medical ethics (Bioethics, Cambridge Quarterly of Healthcare Ethics, Hastings Center Report, Journal of Clinical Ethics, Journal of Medical Ethics, Kennedy Institute of Ethics Journal, Nursing Ethics, Christian Bioethics, andTheoretical Medicine and Bioethics). Results In total, 4029 articles published between 1990 and 2003 were retrieved from the journals studied. Over this period, 435 (10.8%) studies used an empirical design. The highest percentage of empirical research articles appeared in Nursing Ethics (n?=?145, 39.5%), followed by the Journal of Medical Ethics (n?=?128, 16.8%) and the Journal of Clinical Ethics (n?=?93, 15.4%). These three journals account for 84.1% of all empirical research in bioethics published in this period. The results of the ?2 test for two independent samples for the entire dataset indicate that the period 1997–2003 presented a higher number of empirical studies (n?=?309) than did the period 1990–1996 (n?=?126). This increase is statistically significant (?2?=?49.0264, p<.0001). Most empirical studies employed a quantitative paradigm (64.6%, n?=?281). The main topic of research was prolongation of life and euthanasia (n?=?68). Conclusions We conclude that the proportion of empirical research in the nine journals increased steadily from 5.4% in 1990 to 15.4% in 2003. It is likely that the importance of empirical methods in medical ethics and bioethics will continue to increase.

Borry, P; Schotsmans, P; Dierickx, K

2006-01-01

262

Technologies of quantitative, color, and dynamic image analysis  

NASA Astrophysics Data System (ADS)

Methods of analysis of objects characterized by wide variety of sizes, shapes, color and type of dynamics are described. Application of automatic video control systems for granulometric analysis of various metal powders and grinded materials used in dispenser elements of electrovacuum devices is illustrated. The results of color analysis of millet seeds images having different color shade are given. The features of optoelectronic detection and computer diagnostics of complex movements of the freshwater crayfish Daphnia eye are considered.

Abramov, Anton V.; Usanov, Dmitry A.; Skripal, Alexander V.; Usanov, Andrey D.; Skripal, Anatoli V.

2002-05-01

263

ImatraNMR: Novel software for batch integration and analysis of quantitative NMR spectra  

NASA Astrophysics Data System (ADS)

Quantitative NMR spectroscopy is a useful and important tool for analysis of various mixtures. Recently, in addition of traditional quantitative 1D 1H and 13C NMR methods, a variety of pulse sequences aimed for quantitative or semiquantitative analysis have been developed. To obtain actual usable results from quantitative spectra, they must be processed and analyzed with suitable software. Currently, there are many processing packages available from spectrometer manufacturers and third party developers, and most of them are capable of analyzing and integration of quantitative spectra. However, they are mainly aimed for processing single or few spectra, and are slow and difficult to use when large numbers of spectra and signals are being analyzed, even when using pre-saved integration areas or custom scripting features. In this article, we present a novel software, ImatraNMR, designed for batch analysis of quantitative spectra. In addition to capability of analyzing large number of spectra, it provides results in text and CSV formats, allowing further data-analysis using spreadsheet programs or general analysis programs, such as Matlab. The software is written with Java, and thus it should run in any platform capable of providing Java Runtime Environment version 1.6 or newer, however, currently it has only been tested with Windows and Linux (Ubuntu 10.04). The software is free for non-commercial use, and is provided with source code upon request.

Mäkelä, A. V.; Heikkilä, O.; Kilpeläinen, I.; Heikkinen, S.

2011-08-01

264

Biomonitoring and risk assessment on earth and during exploratory missions using AquaHab ®  

NASA Astrophysics Data System (ADS)

Bioregenerative closed ecological life support systems (CELSS) will be necessary in the exploration context revitalizing atmosphere, waste water and producing food for the human CELSS mates. During these long-term space travels and stays far away from Earth in an hostile environment as well as far for example from any hospital and surgery potential, it will be necessary to know much more about chemical and drug contamination in the special sense and by human's themselves in detail. Additionally, there is a strong need on Earth for more relevant standardized test systems including aquatic ones for the prospective risk assessment of chemicals and drugs in general on a laboratory scale. Current standardized test systems are mono species tests, and thus do not represent system aspects and have reduced environmental relevance. The experience gained during the last years in our research group lead to the development of a self-sustaining closed aquatic habitat/facility, called AquaHab ® which can serve regarding space exploration and Earth application. The AquaHab ® module can be the home of several fish species, snails, plants, amphipods and bacteria. The possibility to use different effect endpoints with certain beneficial characteristics is the basis for the application of AquaHab ® in different fields. Influence of drugs and chemicals can be tested on several trophic levels and ecosystem levels; guaranteeing a high relevance for aquatic systems in the real environment. Analyses of effect parameters of different complexity (e.g. general biological and water chemical parameters, activity of biotransforming enzymes) result in broad spectra of sensitivity. Combined with residual analyses (including all metabolites), this leads to an extended prospective risk assessment of a chemical on Earth and in a closed Life Support System. The possibility to measure also sensitive "online" parameters (e.g. behavior, respiration/photosynthetic activity) enables a quick and sensitive effect analysis of water contaminants in respective environments. AquaHab ® is currently under development to an early warning biomonitoring system using genetically modified fish and green algae. The implementation of biosensors/biochip in addition is also discussed.

Slenzka, K.; Dünne, M.; Jastorff, B.

2008-12-01

265

Quantitative Analysis of the Leakage of Confidential Data  

Microsoft Academic Search

Abstract Basic information theory is used to analyse the amount of confidential information which may be leaked by programs written in a very simple imperative language. In particular, a detailed analysis is given of the possible leakage due to equality tests and if statements. The analysis is presented as a set of syntax-directed inference rules and can readily be automated.

David Clark; Sebastian Hunt; Pasquale Malacaria

2001-01-01

266

Quantitative SWOT analysis on global competitiveness of machine tool industry  

Microsoft Academic Search

The strategic importance of global competitiveness of the machine tool industry in Japan is steadily increasing, and therefore machine tool manufacturers require effective corporate strategy to achieve sustainable competitive advantages. Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis is one of the most effective approaches used for analysing strategic management policy of an organization. However, the use of conventional SWOT analysis

H. Shinno; H. Yoshioka; S. Marpaung; S. Hachiga

2006-01-01

267

Response Neighborhoods in Online Learning Networks: A Quantitative Analysis  

ERIC Educational Resources Information Center

Theoretical foundation of Response mechanisms in networks of online learners are revealed by Statistical Analysis of p* Markov Models for the Networks. Our comparative analysis of two networks shows that the minimal-effort hunt-for-social-capital mechanism controls a major behavior of both networks: negative tendency to respond. Differences in…

Aviv, Reuven; Erlich, Zippy; Ravid, Gilad

2005-01-01

268

SWOT with a quantitative outlook: re-visiting the analysis  

Microsoft Academic Search

This article is a conceptual undertaking and looks at one of the most popular qualitative analysis techniques, the SWOT analysis. The technique suggested in this article has been empirically tested and developed based on the logical empiricists approach with a view to strengthen the present highly subjective technique. The new approach is expected to show higher validity, reliability and comprehensiveness

S. F. Anwar; S. R. Siddique

2000-01-01

269

Introducing quantitative life cycle analysis into the chemical engineering curriculum  

Microsoft Academic Search

This paper briefly describes the various stages used to perform the life cycle analysis (LCA) of a product or process. The analysis is simplified in its outputs in that it focuses only on energy usage and carbon and sulfur dioxide emissions. The main point however, is to provide examples to first year engineering and science students that illustrate the principle

G. M. Evans; K. P. Galvin; E. Doroodchi

2008-01-01

270

Use of Atmospheric Infrared Sounder high-spectral resolution spectra to assess the calibration of Moderate resolution Imaging Spectroradiometer on EOS Aqua  

Microsoft Academic Search

AIRS and MODIS on the EOS Aqua spacecraft collect global observations of the Earth's upwelling infrared radiance for numerous remote sensing and climate related applications. This paper presents comparisons of the AIRS and MODIS radiance observations and illustrates the utility of using high-spectral resolution observations to create a highly accurate assessment of broadband sensor calibration. In the analysis, the high-spectral

David C. Tobin; Henry E. Revercomb; Christopher C. Moeller; Thomas S. Pagano

2006-01-01

271

Use of Atmospheric Infrared Sounder high–spectral resolution spectra to assess the calibration of Moderate resolution Imaging Spectroradiometer on EOS Aqua  

Microsoft Academic Search

AIRS and MODIS on the EOS Aqua spacecraft collect global observations of the Earth's upwelling infrared radiance for numerous remote sensing and climate related applications. This paper presents comparisons of the AIRS and MODIS radiance observations and illustrates the utility of using high–spectral resolution observations to create a highly accurate assessment of broadband sensor calibration. In the analysis, the high–spectral

David C. Tobin; Henry E. Revercomb; Christopher C. Moeller; Thomas S. Pagano

2006-01-01

272

Quantitative Analysis of Venus Radar Backscatter Data in Arcgis.  

National Technical Information Service (NTIS)

Ongoing mapping of the Ganiki Planitia (V14) quadrangle of Venus and definition of material units has involved an integrated but qualitative analysis of Magellan radar backscatter images and topography using standard geomorphological mapping techniques. H...

S. M. Long E. B. Grosfils

2005-01-01

273

Idiographic Data Analysis: Quantitative Methods—From Simple to Advanced  

Microsoft Academic Search

Time series analysis is a technique which can be used to model a large number of repeated measurements taken from a single\\u000a case. This makes it a valuable approach for social scientists who are interested in idiographic data analysis. A fundamental\\u000a time series model is the autoregressive moving average (ARMA) model. In this chapter we introduce the reader to the

Ellen L. Hamaker; Conor V. Dolan

2009-01-01

274

Quantitative analysis of actin patch movement in yeast.  

PubMed Central

To investigate the mechanism of cortical actin patch movement in yeast, we implement a method for computer tracking the motion of the patches. Digital images from fluorescence microscope movies of living cells are fed into an image-processing program, which generates two-dimensional patch coordinates in the plane of focus for each movie frame via an algorithm based on detection of rapid intensity variations. The patch coordinates in neighboring frames are connected by a minimum-distance algorithm. The method is used to analyze control cells and cells treated with the actin-depolymerizing agent latrunculin. The motion of the patches in both cases, as analyzed by mean-square patch displacements, is found to be a random walk on average, with a much lower diffusion coefficient for the latrunculin-treated cells. The mean-squared patch travel distances for all of the latrunculin-treated cells are lower than those for all of the control cells. The patches move independently of one another. We develop a quantitative criterion for the presence of directed motion, and show that numerous patches in the control cells display directed motion to a very high degree of certainty. A small number of patches in the latrunculin-treated cells display directed motion.

Carlsson, A E; Shah, A D; Elking, D; Karpova, T S; Cooper, J A

2002-01-01

275

Quantitative Proteomic Analysis of Ribosome Assembly and Turnover In Vivo  

PubMed Central

Although high-resolution structures of the ribosome have been solved in a series of functional states, relatively little is known about how the ribosome assembles, particularly in vivo. Here, a general method is presented for studying the dynamics of ribosome assembly and ribosomal assembly intermediates. Since significant quantities of assembly intermediates are not present under normal growth conditions, the antibiotic neomycin is used to perturb wild type E. coli. Treatment of E. coli with the antibiotic neomycin results in the accumulation of a continuum of assembly intermediates for both the 30S and 50S subunits. The protein composition and the protein stoichiometry of these intermediates were determined by quantitative mass spectrometry using purified unlabeled and 15N-labeled wild type ribosomes as external standards. The intermediates throughout the continuum are heterogeneous and are largely depleted of late-binding proteins. Pulse labeling with 15N-labeled medium timestamps the ribosomal proteins based on their time of synthesis. The assembly intermediates contain both newly synthesized proteins and proteins that originated in previously synthesized intact subunits. This observation requires either a significant amount of ribosome degradation, or the exchange or reuse of ribosomal proteins. These specific methods can be applied to any system where ribosomal assembly intermediates accumulate, including strains with deletions or mutations of assembly factors. This general approach can be applied to study the dynamics of assembly and turnover of other macromolecular complexes that can be isolated from cells.

Sykes, Michael T.; Shajani, Zahra; Sperling, Edit; Beck, Andrea H.; Williamson, James R.

2010-01-01

276

Quantitative Analysis of Synaptic Release at the Photoreceptor Synapse  

PubMed Central

Abstract Exocytosis from the rod photoreceptor is stimulated by submicromolar Ca2+ and exhibits an unusually shallow dependence on presynaptic Ca2+. To provide a quantitative description of the photoreceptor Ca2+ sensor for exocytosis, we tested a family of conventional and allosteric computational models describing the final Ca2+-binding steps leading to exocytosis. Simulations were fit to two measures of release, evoked by flash-photolysis of caged Ca2+: exocytotic capacitance changes from individual rods and postsynaptic currents of second-order neurons. The best simulations supported the occupancy of only two Ca2+ binding sites on the rod Ca2+ sensor rather than the typical four or five. For most models, the on-rates for Ca2+ binding and maximal fusion rate were comparable to those of other neurons. However, the off-rates for Ca2+ unbinding were unexpectedly slow. In addition to contributing to the high-affinity of the photoreceptor Ca2+ sensor, slow Ca2+ unbinding may support the fusion of vesicles located at a distance from Ca2+ channels. In addition, partial sensor occupancy due to slow unbinding may contribute to the linearization of the first synapse in vision.

Duncan, Gabriel; Rabl, Katalin; Gemp, Ian; Heidelberger, Ruth; Thoreson, Wallace B.

2010-01-01

277

Quantitative analysis of chaperone network throughput in budding yeast  

PubMed Central

The network of molecular chaperones mediates the folding and translocation of the many proteins encoded in the genome of eukaryotic organisms, as well as a response to stress. It has been particularly well characterised in the budding yeast, Saccharomyces cerevisiae, where 63 known chaperones have been annotated and recent affinity purification and MS/MS experiments have helped characterise the attendant network of chaperone targets to a high degree. In this study, we apply our QconCAT methodology to directly quantify the set of yeast chaperones in absolute terms (copies per cell) via SRM MS. Firstly, we compare these to existing quantitative estimates of these yeast proteins, highlighting differences between approaches. Secondly, we cast the results into the context of the chaperone target network and show a distinct relationship between abundance of individual chaperones and their targets. This allows us to characterise the ‘throughput’ of protein molecules passing through individual chaperones and their groups on a proteome-wide scale in an unstressed model eukaryote for the first time. The results demonstrate specialisations of the chaperone classes, which display different overall workloads, efficiencies and preference for the sub-cellular localisation of their targets. The novel integration of the interactome data with quantification supports re-estimates of the level of protein throughout going through molecular chaperones. Additionally, although chaperones target fewer than 40% of annotated proteins we show that they mediate the folding of the majority of protein molecules (?62% of the total protein flux in the cell), highlighting their importance.

Brownridge, Philip; Lawless, Craig; Payapilly, Aishwarya B; Lanthaler, Karin; Holman, Stephen W; Harman, Victoria M; Grant, Christopher M; Beynon, Robert J; Hubbard, Simon J

2013-01-01

278

Quantitative analysis of chromosome condensation in fission yeast.  

PubMed

Chromosomes undergo extensive conformational rearrangements in preparation for their segregation during cell divisions. Insights into the molecular mechanisms behind this still poorly understood condensation process require the development of new approaches to quantitatively assess chromosome formation in vivo. In this study, we present a live-cell microscopy-based chromosome condensation assay in the fission yeast Schizosaccharomyces pombe. By automatically tracking the three-dimensional distance changes between fluorescently marked chromosome loci at high temporal and spatial resolution, we analyze chromosome condensation during mitosis and meiosis and deduct defined parameters to describe condensation dynamics. We demonstrate that this method can determine the contributions of condensin, topoisomerase II, and Aurora kinase to mitotic chromosome condensation. We furthermore show that the assay can identify proteins required for mitotic chromosome formation de novo by isolating mutants in condensin, DNA polymerase ?, and F-box DNA helicase I that are specifically defective in pro-/metaphase condensation. Thus, the chromosome condensation assay provides a direct and sensitive system for the discovery and characterization of components of the chromosome condensation machinery in a genetically tractable eukaryote. PMID:23263988

Petrova, Boryana; Dehler, Sascha; Kruitwagen, Tom; Hériché, Jean-Karim; Miura, Kota; Haering, Christian H

2012-12-21

279

Quantitative analysis of TRP channel genes in mouse organs.  

PubMed

The transient receptor potential (TRP) channel superfamily is a set of channel genes that mediate numerous physiological functions such as sensing irritants or detecting temperature changes. Despite their functions, expressional information on TRP channels in various organs is largely elusive. Therefore, we conducted a systematic quantitative comparison of each mRNA expression level of 22 mouse TRP channels in various organs. As a result, we found that average levels of TRP channel transcripts were very low reaching ?3% of the GAPDH transcript level. Among 22 TRP channels, TRPC1 and TRPM7 were most abundant in the majority of organs. In contrast, TRPV3, TRPV5, TRPV6, TRPC7, TRPM1, and TRPM5 elicited very low message profiles throughout the major organs. Consistent with their functions as molecular sensors for irritants and temperature changes, TRPV1, TRPM8 and TRPA1 showed exclusive expression in sensory ganglia. TRPC3 and TRPM3 were abundant in the sensory ganglia and brain. High levels of transcripts of TRPV2, TRPC6, TRPM4, and TRPM6 were observed in the lung. In addition, channel transcript levels were very low except TRPM7 in the liver. In summary, the expression profile of TRP channels in major tissues provides insight to their physiological functions and therefore application to new drug development. PMID:23139135

Jang, Yongwoo; Lee, Yunjong; Kim, Sung Min; Yang, Young Duk; Jung, Jooyoung; Oh, Uhtaek

2012-11-09

280

Quantitative analysis of extension-torsion coupling of actin filaments.  

PubMed

Actin filaments have a double-helix structure consisting of globular actin molecules. In many mechanical cellular activities, such as cell movement, division, and shape control, modulation of the extensional and torsional dynamics of the filament has been linked to regulatory actin-binding protein functions. Therefore, it is important to quantitatively evaluate extension-torsion coupling of filament to better understand the actin filament dynamics. In the present study, the extension-torsion coupling was investigated using molecular dynamics simulations. We constructed a model for the actin filament consisting of 14 actin subunits in an ionic solvent as a minimal functional unit, and analyzed longitudinal and twisting Brownian motions of the filament. We then derived the expected value of energy associated with extension and torsion at equilibrium, and evaluated the extension-torsion stiffness of the filament from the thermal fluctuations obtained from the MD simulations. The results demonstrated that as the analyzed sampling-window duration was increased, the extension-torsion coupling stiffness evaluated on a nanosecond scale tended to converge to a value of 7.6×10(-11) N. The results obtained from this study will contribute to the understanding of biomechanical events, under mechanical tension and torque, involving extension-torsion coupling of filaments. PMID:22366037

Matsushita, Shinji; Inoue, Yasuhiro; Adachi, Taiji

2012-02-15

281

Quantitative XRD analysis of {110} twin density in biotic aragonites.  

PubMed

{110} Twin densities in biotic aragonite have been estimated quantitatively from the peak widths of specific reflections in powder X-ray diffraction (XRD) patterns, as well as direct confirmation of the twins using transmission electron microscopy (TEM). Influence of the twin density on the peak widths in the XRD pattern was simulated using DIFFaX program, regarding (110) twin as interstratification of two types of aragonite unit layers with mirrored relationship. The simulation suggested that the twin density can be estimated from the difference of the peak widths between 111 and 021, or between 221 and 211 reflections. Biotic aragonite in the crossed-lamellar microstructure (three species) and nacreous microstructure (four species) of molluscan shells, fish otoliths (two species), and a coral were investigated. The XRD analyses indicated that aragonite crystals in the crossed-lamellar microstructure of the three species contain high density of the twins, which is consistent with the TEM examination. On the other hand, aragonite in the nacre of the four species showed almost no difference of the peak widths between the paired reflections, indicating low twin densities. The results for the fish otoliths were varied between the species. Such variation of the twin density in biotic aragonites may reflect different schemes of crystal growth in biomineralization. PMID:22989562

Suzuki, Michio; Kim, Hyejin; Mukai, Hiroki; Nagasawa, Hiromichi; Kogure, Toshihiro

2012-09-16

282

Quantitative analysis of pheromone-binding protein specificity.  

PubMed

Many pheromones have very low water solubility, posing experimental difficulties for quantitative binding measurements. A new method is presented for determining thermodynamically valid dissociation constants for ligands binding to pheromone-binding proteins, using ?-cyclodextrin as a solubilizer and transfer agent. The method is applied to LUSH, a Drosophila odorant-binding protein that binds the pheromone 11-cis vaccenyl acetate (cVA). Refolding of LUSH expressed in Escherichia?coli was assessed by measuring N-phenyl-1-naphthylamine (NPN) binding and Förster resonance energy transfer between LUSH tryptophan 123 (W123) and NPN. Binding of cVA was measured from quenching of W123 fluorescence as a function of cVA concentration. The equilibrium constant for transfer of cVA between ?-cyclodextrin and LUSH was determined from a linked equilibria model. This constant, multiplied by the ?-cyclodextrin-cVA dissociation constant, gives the LUSH-cVA dissociation constant: ?100 nM. It was also found that other ligands quench W123 fluorescence. The LUSH-ligand dissociation constants were determined to be ?200?nM for the silk moth pheromone bombykol and ?90?nM for methyl oleate. The results indicate that the ligand-binding cavity of LUSH can accommodate a variety ligands with strong binding interactions. Implications of this for the Laughlin, Ha, Jones and Smith model of pheromone reception are discussed. PMID:23121132

Katti, S; Lokhande, N; González, D; Cassill, A; Renthal, R

2012-11-01

283

Quantitative analysis of in-air output ratio.  

PubMed

Output factor (Scp) is one of the important factors required to calculate monitor unit (MU), and is divided into two components: phantom scatter factor (Sp) and in-air output ratio (Sc). Generally, Sc for arbitrary fields are calculated using several methods based on Sc determined by the absorbed dose measurement for several square fields. However, there are calculation errors when the treatment field has a large aspect ratio and the opening of upper and lower collimator are exchanged. To determine Sc accurately, scattered photons from the treatment head and backscattered particles into the monitor chamber must be analyzed individually. In this report, a simulation model that agreed well with measured Sc was constructed and dose variation by scattered photons from the treatment head and by backscattered particles into the monitor chamber was analyzed quantitatively. The results showed that the contribution of scattered photons from the primary collimator was larger than that of the flattening filter, and backscattered particles were affected by not only the upper jaw but also the lower jaw. In future work, a new Sc determination algorism based on the result of this report will be proposed. PMID:23292148

Miyashita, Hisayuki; Hatanaka, Shogo; Fujita, Yukio; Hashimoto, Shimpei; Myojyoyama, Atsushi; Saitoh, Hidetoshi

2013-01-04

284

Quantitative Determination and Analysis of Visual Receptive Fields.  

NASA Astrophysics Data System (ADS)

A unique approach to obtaining nonbiased quantitative information on visual receptive fields is examined. This approach involves placing the animal in a feedback and control loop, and inverting the pattern recognition process. In a preliminary application, receptive fields are determined via a random scanning technique. The system moves predetermined stimuli around on a cathode ray tube viewed by the animal, while recording extracellularly from retinal ganglion fibers in the tectum. Digitized response waveforms are saved and analyzed by extensive software to characterize the receptive field. In the primary application, the receptive field is determined by a stochastic technique using response feedback. In iterative fashion, initially random patterns are modified by the algorithm enabling the animal to generate visual patterns optimizing some measure of the response. Characteristics of the receptive field as determined by the two different techniques are contrasted in many runs, and are compared to classically determined receptive field characteristics. The detailed nature of the responses to stimuli is examined. The problem of optimizing the second technique of receptive field determination by response feedback is explored via simulation. The response feedback technique is shown to converge successfully on receptive field patterns in actual physiological runs. The capability of the technique to provide unique results is discussed. In addition to providing a check on the response feedback technique, the results of the random scan technique demonstrate the separability of independent units on the basis of pulse height. Also, many units were found to undergo rhythmic bursting.

Michalak, Richard Joseph

285

Quantitative analysis of the expression of a VIP transgene.  

PubMed

We have analyzed the expression of a transgene bearing 2 kilobases of the 5' flanking region of the human vasoactive intestinal polypeptide (VIP) gene coupled to beta-galactosidase. Expression was assayed by beta-galactosidase histochemistry and by mRNA quantitation using polymerase chain reaction (PCR)-mediated amplification; we compared beta-galactosidase activity against both transgene and endogenous VIP mRNA levels. We found that the human 5' flanking sequence in this construct is able to direct tissue-specific expression of beta-galactosidase similar to the pattern for endogenous VIP. However, the transgene is also expressed in smooth muscle and Schwann cells, where VIP mRNA is rare. In various tissues where the transgene and endogenous gene are both active, the ratio between their message levels differs dramatically--transgene mRNA is more abundant where VIP is relatively scarce, but is much less abundant than the endogenous message at sites where VIP mRNA is most concentrated. These results suggest that sequence elements that may restrict VIP transcription or cause tissue-specific VIP mRNA accumulation are missing from the transgene. In the testis there is a high level of transgene message but no significant beta-galactosidase activity; this discrepancy is caused by transcription from a cryptic promoter within the beta-galactosidase sequence. PMID:8774945

Tolentino, P J; Dikkes, P; Tsuruda, L; Ebert, K; Fink, J S; Villa-Komaroff, L; Lamperti, E D

1995-10-01

286

Morphological analysis of the proximal femur using quantitative computed tomography  

PubMed Central

The anatomy of the proximal femur was studied in 35 specimens using quantitative computed tomography (QCT) and compared with anatomical sections studied by plane radiography and gross dissection. We found the primary supporting structure of the femoral head to be the primary compressive strut, which is a dense column of trabecular bone projecting from the pressure buttress of the medial femoral neck to the epiphyseal scar. Trabecular bone mushroomed from the epiphyseal scar and terminated at right angles to the cortex of the femoral head. We believe the primary compressive strut is the predominant load-bearing structure connecting the femoral head to the femoral neck, as many specimens lacked continuity of the head cortex to the femoral neck. Based on the CT number, the primary compressive strut had similar bone density to cortical structures such as the lesser trochanter, calcar femorale and posterior lateral femoral cortex. Ward’s triangle lacked structural integrity in many cases, and we doubt the significance of tensile trabculae for sharing load. Surgical techniques such as femoral fracture fixation, resurfacing hip arthroplasty and allograft transplantation may benefit from this knowledge.

Jacobson, Donald; Carrera, Guilermo

2006-01-01

287

[Quantitative spectrum analysis of characteristic gases of spontaneous combustion coal].  

PubMed

Aimed at the characteristics of spontaneous combustion gas such as a variety of gases, lou limit of detection, and critical requirement of safety, Fourier transform infrared (FTIR) spectral analysis is presented to analyze characteristic gases of spontaneous combustion In this paper, analysis method is introduced at first by combing characteristics of absorption spectra of analyte and analysis requirement. Parameter setting method, sample preparation, feature variable abstract and analysis model building are taken into consideration. The methods of sample preparation, feature abstraction and analysis model are introduced in detail. And then, eleven kinds of gases were tested with Tensor 27 spectrometer. CH4, C2H6, C3H8, iC4H10, nC4H10, C2 H4, C3 H6, C3 H2, SF6, CO and CO2 were included. The optical path length was 10 cm while the spectra resolution was set as 1 cm(-1). The testing results show that the detection limit of all analytes is less than 2 x 10(-6). All the detection limits fit the measurement requirement of spontaneous combustion gas, which means that FTIR may be an ideal instrument and the analysis method used in this paper is competent for spontaneous combustion gas measurement on line. PMID:22097853

Liang, Yun-Tao; Tang, Xiao-Jun; Luo, Hai-Zhu; Sun, Yong

2011-09-01

288

Advancing Genetic Theory and Application by Metabolic Quantitative Trait Loci Analysis  

PubMed Central

This review describes recent advances in the analysis of metabolism using quantitative genetics. It focuses on how recent metabolic quantitative trait loci (QTL) studies enhance our understanding of the genetic architecture underlying naturally variable phenotypes and the impact of this fundamental research on agriculture, specifically crop breeding. In particular, the role of whole-genome duplications in generating quantitative genetic variation within a species is highlighted and the potential uses of this phenomenon presented. Additionally, the review describes how new observations from metabolic QTL mapping analyses are helping to shape and expand the concepts of genetic epistasis.

Kliebenstein, DanielJ.

2009-01-01

289

Software applications toward quantitative metabolic flux analysis and modeling.  

PubMed

Metabolites and their pathways are central for adaptation and survival. Metabolic modeling elucidates in silico all the possible flux pathways (flux balance analysis, FBA) and predicts the actual fluxes under a given situation, further refinement of these models is possible by including experimental isotopologue data. In this review, we initially introduce the key theoretical concepts and different analysis steps in the modeling process before comparing flux calculation and metabolite analysis programs such as C13, BioOpt, COBRA toolbox, Metatool, efmtool, FiatFlux, ReMatch, VANTED, iMAT and YANA. Their respective strengths and limitations are discussed and compared to alternative software. While data analysis of metabolites, calculation of metabolic fluxes, pathways and their condition-specific changes are all possible, we highlight the considerations that need to be taken into account before deciding on a specific software. Current challenges in the field include the computation of large-scale networks (in elementary mode analysis), regulatory interactions and detailed kinetics, and these are discussed in the light of powerful new approaches. PMID:23142828

Dandekar, Thomas; Fieselmann, Astrid; Majeed, Saman; Ahmed, Zeeshan

2012-11-01

290

iTRAQ-based quantitative proteomic analysis of Thermobifida fusca reveals metabolic pathways of cellulose utilization  

Microsoft Academic Search

Thermobifida fusca is an aerobic, thermophilic, cellulose degrading bacterium identified in heated organic materials. This study applied iTRAQ quantitative proteomic analysis to the cellular and membrane proteomes of T. fusca grown in presence and absence of cellulose to elucidate the cellular processes induced by cellulose nutrient. Using an iTRAQ-based quantitative proteomic approach, 783 cytosolic and 181 membrane proteins expressed during

Sunil S. Adav; Chee Sheng Ng; Siu Kwan Sze

2011-01-01

291

Dynamic and still microcirculatory image analysis for quantitative microcirculation research  

NASA Astrophysics Data System (ADS)

Based on analyses of various types of digital microcirculatory image (DMCI), we summed up the image features of DMCI, the digitizing demands for digital microcirculatory imaging, and the basic characteristics of the DMCI processing. A dynamic and still imaging separation processing (DSISP) mode was designed for developing a DMCI workstation and the DMCI processing. Original images in this study were clinical microcirculatory images from human finger nail-bed and conjunctiva microvasculature, and intravital microvascular network images from animal tissue or organs. A series of dynamic and still microcirculatory image analysis functions were developed in this study. The experimental results indicate most of the established analog video image analysis methods for microcirculatory measurement could be realized in a more flexible way based on the DMCI. More information can be rapidly extracted from the quality improved DMCI by employing intelligence digital image analysis methods. The DSISP mode is very suitable for building a DMCI workstation.

Ying, Xiaoyou; Xiu, Rui-juan

1994-05-01

292

Geysers of Enceladus: Quantitative analysis of qualitative models  

NASA Astrophysics Data System (ADS)

Aspects of two qualitative models of Enceladus’ dust plume—the so-called “Cold Faithful” [Porco, C.C., et al., 2006. Cassini observes the active south pole of Enceladus. Science 311, 1393 1401; Ingersoll, A.P., et al., 2006. Models of the Enceladus plumes. In: Bulletin of the American Astronomical Society, vol. 38, p. 508] and “Frigid Faithful” [Kieffer, S.W., et al., 2006. A clathrate reservoir hypothesis for Enceladus’ south polar plume. Science 314, 1764; Gioia, G., et al., 2007. Unified model of tectonics and heat transport in a Frigid Enceladus. Proc. Natl. Acad. Sci. 104, 13578 13591] models—are analyzed quantitatively. The former model assumes an explosive boiling of subsurface liquid water, when pressure exerted by the ice crust is suddenly released due to an opening crack. In the latter model the existence of a deep shell of clathrates below Enceladus’ south pole is conjectured; clathrates can decompose explosively when exposed to vacuum through a fracture in the outer icy shell. For the Cold Faithful model we estimate the maximal velocity of ice grains, originating from water splashing in explosive boiling. We find that for water near the triple point this velocity is far too small to explain the observed plume properties. For the Frigid Faithful model we consider the problem of momentum transfer from gas to ice particles. It arises since any change in the direction of the gas flow in the cracks of the shell requires re-acceleration of the entrained grains. While this effect may explain the observed speed difference of gas and grains if the gas evaporates from triple point temperature (273.15 K) [Schmidt, J., et al., 2008. Formation of Enceladus dust plume. Nature 451, 685], the low temperatures of the Frigid Faithful model (˜140 170K) imply a too dilute vapor to support the observed high particle fluxes in Enceladus’ plume.

Brilliantov, Nikolai V.; Schmidt, Jürgen; Spahn, Frank

2008-11-01

293

Quantitative determination of total lipid hydroperoxides by a flow injection analysis system  

Microsoft Academic Search

A flow injection analysis (FIA) system coupled with a fluorescence detection system using diphenyl-1-pyrenylphosphine (DPPP)\\u000a was developed as a highly sensitive and reproducible quantitative method of total lipid hydroperoxide analysis. Fluorescence\\u000a analysis of DPPP oxide generated by the reaction of lipid hydroperoxides with DPPP enabled a quantitative determination of\\u000a the total amount of lipid hydroperoxides. Use of 1-myristoyl-2-(12-((7-nitro-2-1,3-benzoxadiazol-4-yl)amino) dodecanoyl)-sn-glycero-3-phosphocholine as

Jeong-Ho Sohn; Yusuke Taki; Hideki Ushio; Toshiaki Ohshima

2005-01-01

294

The Quantitative Analysis of an Analgesic Tablet: An NMR Experiment for the Instrumental Analysis Course  

NASA Astrophysics Data System (ADS)

A quantitative analysis experiment is outlined that uses 13C NMR. Initial work utilizes a known compound (acenapthene) to assess the type of NMR experiment necessary to achieve a proportional response from all of the carbons in the compound. Both gated decoupling and inverse gated decoupling routines with a variety of delay times are inspected, in addition to investigation of paramagnetic additives in conjunction with inverse gated decoupling. Once the experiments with the known compound have illuminated the merits of the differing strategies for obtaining a proportional carbon response, a quantitative assessment of an unknown analgesic tablet is undertaken. The amounts of the two major components of the tablet, acetaminophen and aspirin, are determined following addition of an internal standard to the mixture. The carbon resonances emanating from each compound can be identified using spectra of the pure analgesic components and internal standard. Knowing the concentration of the internal standard and assuming a proportional response to all carbons in the sample allows calculation of the amount of both analytes in the analgesic tablets. Data from an initial laboratory trial is presented that illustrates the accuracy of the procedure.

Schmedake, Thomas A.; Welch, Lawrence E.

1996-11-01

295

Quantitative proteomics analysis of adsorbed plasma proteins classifies nanoparticles with different surface properties and size  

SciTech Connect

In biofluids (e.g., blood plasma) nanoparticles are readily embedded in layers of proteins that can affect their biological activity and biocompatibility. Herein, we report a study on the interactions between human plasma proteins and nanoparticles with a controlled systematic variation of properties using stable isotope labeling and liquid chromatography-mass spectrometry (LC-MS) based quantitative proteomics. Novel protocol has been developed to simplify the isolation of nanoparticle bound proteins and improve the reproducibility. Plasma proteins associated with polystyrene nanoparticles with three different surface chemistries and two sizes as well as for four different exposure times (for a total of 24 different samples) were identified and quantified by LC-MS analysis. Quantitative comparison of relative protein abundances were achieved by spiking an 18 O-labeled 'universal reference' into each individually processed unlabeled sample as an internal standard, enabling simultaneous application of both label-free and isotopic labeling quantitation across the sample set. Clustering analysis of the quantitative proteomics data resulted in distinctive pattern that classifies the nanoparticles based on their surface properties and size. In addition, data on the temporal study indicated that the stable protein 'corona' that was isolated for the quantitative analysis appeared to be formed in less than 5 minutes. The comprehensive results obtained herein using quantitative proteomics have potential implications towards predicting nanoparticle biocompatibility.

Zhang, Haizhen; Burnum, Kristin E.; Luna, Maria L.; Petritis, Brianne O.; Kim, Jong Seo; Qian, Weijun; Moore, Ronald J.; Heredia-Langner, Alejandro; Webb-Robertson, Bobbie-Jo M.; Thrall, Brian D.; Camp, David G.; Smith, Richard D.; Pounds, Joel G.; Liu, Tao

2011-12-01

296

Grid-Enabled Quantitative Analysis of Breast Cancer.  

National Technical Information Service (NTIS)

The tong-term goat of this research is to improve breast cancer diagnosis, risk assessment, response assessment, ana patient care via the use of large-scale, multi-modality computerized image analysis. The central hypothesis of this research is that large...

A. R. Jamieson

2010-01-01

297

Grid-Enabled Quantitative Analysis of Breast Cancer.  

National Technical Information Service (NTIS)

The long-term goal of this research is to improve breast cancer diagnosis, risk assessment, response assessment, and patient care via the use of large-scale, multi-modality computerized image analysis. The central hypothesis of this research is that large...

A. R. Jamieson H. Li K. Drukker L. Pesce M. L. Giger

2009-01-01

298

QUANTITATIVE ANALYSIS OF PHYTATE IN SOYBEAN AND SOYBEAN PRODUCTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A rapid and simple analytical procedure for determination of phytate (myo-inositol hexaphosphate) in soybean and soybean products is described. The procedure was based on Rounds and Nielsen's (J. Chromatography 653:148, 1993) approach. Minimal sample preparation and automated HPLC analysis for large...

299

Quantitative image analysis of UV rocket plumes and laboratory images  

Microsoft Academic Search

Rocket plume images photographed with the AFGL UV imager on video system have been analyzed with a video digitizer and an MS-DOS computer. The analysis consists of distortion-free rotation of the images to align the plume axis with the horizontal pixel direction, smoothing the images with appropriate image filters, plotting contours and brightness slices of the images, measuring the size

Donald F. Collins

1988-01-01

300

Quantitative comparison of five current protocols in gait analysis  

Microsoft Academic Search

Data collection and reduction procedures, coherently structured in protocols, are necessary in gait analysis to make kinematic and kinetic measurements clinically comprehensible. The current protocols differ considerably for the marker-set and for the biomechanical model implemented. Nevertheless, conventional gait variables are compared without full awareness of these differences.A comparison was made of five worldwide representative protocols by analysing kinematics and

Alberto Ferrari; Maria Grazia Benedetti; Esteban Pavan; Carlo Frigo; Dario Bettinelli; Marco Rabuffetti; Paolo Crenna; Alberto Leardini

2008-01-01

301

Automated quantitative gait analysis in animal models of movement disorders  

Microsoft Academic Search

BACKGROUND: Accurate and reproducible behavioral tests in animal models are of major importance in the development and evaluation of new therapies for central nervous system disease. In this study we investigated for the first time gait parameters of rat models for Parkinson's disease (PD), Huntington's disease (HD) and stroke using the Catwalk method, a novel automated gait analysis test. Static

Caroline Vandeputte; Jean-Marc Taymans; Cindy Casteels; Frea Coun; Yicheng Ni; Koen Van Laere; Veerle Baekelandt

2010-01-01

302

Reflectance Spectroscopy: Quantitative Analysis Techniques for Remote Sensing Applications  

Microsoft Academic Search

Several methods for the analysis of remotely sensed reflectance data are compared, including empirical methods and scattering theories, both of which are important for solving remote sensing problems. The concept of the photon mean optical path length and the implications for use in modeling reflectance spectra are presented. It is shown that the mean optical path length in a particulate

Roger N. Clark; Ted L. Roush

1984-01-01

303

QUANTITATIVE ANALYSIS OF HYDROLOGIC CYCLE IN COLD SNOWY BASIN  

Microsoft Academic Search

For comprehensive water management and water environmental planning in large river catchment areas, it is necessary to know the long-term hydrologic cycle. In snowy cold regions, the snow process (falling, accumulation, and melting) plays an important role on the hydrologic cycle. An understanding of snow cover volume and snowmelt volume is essential. Analysis of the water balance of the catchment

Tomohide USUTANI; Makoto NAKATSUGAWA

304

Towards a quantitative analysis of magnetic force microscopy data matrices  

NASA Astrophysics Data System (ADS)

Fast and efficient software tools previously developed in image processing were adapted to the analysis of raw datasets consisting of multiple stacks of images taken on a sample interacting with a measuring instrument and submitted to the effect of an external parameter. Magnetic force microscopy (MFM), a follow-up of atomic force microscopy (AFM), was selected as a first testbed example. In MFM, a specifically developed ferromagnetic scanning tip probes the stray magnetic field generated from a ferromagnetic specimen. Raw scanning probe images taken on soft patterned magnetic materials and continuous thin films were used, together with synthetic patterns exploited to assess the absolute performance ability of the proposed texture analysis tools. In this case, the parameter affecting the sample-instrument interaction is the applied magnetic field. The application discussed here is just one among the many possible, including, e.g., real-time microscopy images (both optical and electronic) taken during heat treatments, phase transformations and so on. Basically any image exhibiting a texture with a characteristic spatial or angular dependence could be processed by the proposed method. Standard imaging tools such as texture mapping and novel data representation schemes such as texture analysis, feature extraction and classification are discussed. A magnetic texture stability diagram will be presented as an original output of the entropic analysis on MFM datasets.

Chiolerio, A.; Allia, P.

2012-08-01

305

Axonal microtubules: a computer-linked quantitative analysis  

Microsoft Academic Search

Employing current computer-aided morphometric techniques, axonal microtubule density was determined for the rat sural nerve. Analysis of extensive data showed that while microtubule number increases with axon size, the increase is not directly proportional. Thus the relationship between microtubule density and axonal size is inversely related, so that microtubule density is greater in smaller axons than in larger axons. When

A. M. B. Malbouisson; M. N. Ghabriel; G. Allt

1985-01-01

306

A Quantitative Content Analysis of Mercer University MEd, EdS, and Doctoral Theses  

ERIC Educational Resources Information Center

|Quantitative content analysis of a body of research not only helps budding researchers understand the culture, language, and expectations of scholarship, it helps identify deficiencies and inform policy and practice. Because of these benefits, an analysis of a census of 980 Mercer University MEd, EdS, and doctoral theses was conducted. Each…

Randolph, Justus J.; Gaiek, Lura S.; White, Torian A.; Slappey, Lisa A.; Chastain, Andrea; Harris, Rose Prejean

2010-01-01

307

Kinetic Analysis of Amylase Using Quantitative Benedict's and Iodine Starch Reagents  

ERIC Educational Resources Information Center

|Quantitative analysis of carbohydrates is a fundamental analytical tool used in many aspects of biology and chemistry. We have adapted a technique developed by Mathews et al. using an inexpensive scanner and open-source image analysis software to quantify amylase activity using both the breakdown of starch and the appearance of glucose. Breakdown…

Cochran, Beverly; Lunday, Deborah; Miskevich, Frank

2008-01-01

308

Linkage Disequilibrium Analysis of Quantitative Trait Locus Associated with Lipid Profiles  

Microsoft Academic Search

Background and Objectives:The common methods of genetic association analysis are sensitive to population stratification, which may easily lead to a spurious association result. We used a regression approach based for lin- kage disequilibrium to perform a high resolution genetic association analysis. Subjects and Methods:We applied a regression approach that can increase the resolution of quantitative traits that are related with

Kijun Song; Kil Seob Lim; Jin Nam Cho

2006-01-01

309

Deeper understanding of non-linear geodetic data inversion using a quantitative sensitivity analysis  

Microsoft Academic Search

A quantitative global sensitivity analysis (SA) is applied to the non-linear inversion of gravity changes and displacement data which measured in an active volcanic area. The common inversion of this data is based on the solution of the generalized Navier equations which couples both types of observation, gravity and displacement, in a homogeneous half space. The sensitivity analysis has been

C. Tiede; K. Tiampo; J. Fernández; C. Gerstenecker

2005-01-01

310

Modeling and visualization application of naval battlefield situation quantitative analysis and evaluation  

Microsoft Academic Search

How to analyze the situation of the battlefield in the modern battle, and help the commander to make correct decision is the major orientation of every countriespsila researches. This paper presents a quantitative analysis and evaluation model of naval battlefield situation and gives a corresponding visual analysis model using isoline technology and potential field theory. This model can not only

Xiaobo Niu; Lujing Yang

2008-01-01

311

Good theories deserve good data: Testing theories of interest group influence using quantitative text analysis  

Microsoft Academic Search

The analysis of interest group influence is crucial in order to explain policy outcomes and to assess the democratic legitimacy of the EU. Due to methodological difficulties in operationalizing influence, only few have however studied it. This paper therefore proposes a new approach to influence measurement drawing on quantitative text analysis. By comparing interest groups' policy positions with the final

Heike Klüver

312

Quantitative Analysis of Science and Chemistry Textbooks for Indicators of Reform: A complementary perspective  

Microsoft Academic Search

In this study, multiple thematically based and quantitative analysis procedures were utilized to explore the effectiveness of Turkish chemistry and science textbooks in terms of their reflection of reform. The themes gender equity, questioning level, science vocabulary load, and readability level provided the conceptual framework for the analyses. An unobtrusive research method, content analysis, was used by coding the manifest

Ajda Kahveci

2010-01-01

313

Evaluation of a Quantitative Magnetic Resonance Method for Mouse Whole Body Composition Analysis  

Microsoft Academic Search

Objective: To evaluate applicability, precision, and accuracy of a new quantitative magnetic resonance (QMR) analysis for whole body composition of conscious live mice.Research Methods and Procedures: Repeated measures of body composition were made by QMR, DXA, and classic chemical analysis of carcass using live and dead mice with different body compositions. Caloric lean and dense diets were used to produce

Frank C. Tinsley; Gersh Z. Taicher; Mark L. Heiman

2004-01-01

314

The Quantitative Discrimination between Shrinkage and Gas Microporosity in Cast Aluminum Alloys Using Spatial Data Analysis  

Microsoft Academic Search

Microporosity in cast aluminum alloys may originate from hydrogen gas evolution, microshrinkage, or a combination of both. A spatial analysis method for the quantitative discrimination between shrinkage and gas porosity is presented and explained. It is shown that shrinkage pores can be selected and analyzed separately from gas pores by nearest-neighbor analysis. The principles of spatial statistics are discussed, and

J. P. Anson; J. E. Gruzleski

1999-01-01

315

Computerized System for Quantitative X-Ray Diffraction Analysis of Pyrite in Coal.  

National Technical Information Service (NTIS)

The Bureau of Mines has developed a quantitative analysis for pyrite in coal by X-ray diffraction that can be accomplished in little more than 1 hour. To minimize the sample analysis time, data processing has been completely computerized with pertinent ou...

R. A. Friedel R. R. Schehl

1973-01-01

316

Digitally Enhanced Thin-Layer Chromatography: An Inexpensive, New Technique for Qualitative and Quantitative Analysis  

ERIC Educational Resources Information Center

|A study conducted shows that if digital photography is combined with regular thin-layer chromatography (TLC), it could perform highly improved qualitative analysis as well as make accurate quantitative analysis possible for a much lower cost than commercial equipment. The findings suggest that digitally enhanced TLC (DE-TLC) is low-cost and easy…

Hess, Amber Victoria Irish

2007-01-01

317

Quantitative risk analysis and the production of microbiologically safe food: an introduction  

Microsoft Academic Search

There is increasing interest in the application of quantitative risk analysis (QRA) in the production of microbiologically safe food products. QRA can be defined as a stepwise analysis of health risks which may be associated with a particular type of food product, resulting in an estimation of the probability of occurrence of negative health effects following the consumption of that

S. Notermans; P. Teunis

1996-01-01

318

Quantitative Analysis of Uranium, Thorium and Potassium from Lignite Ash by Neutron Activation Method  

Microsoft Academic Search

Quantitative analysis of uranium, thorium and potassium from lignite ash is determined by Neutron Activation (NA) Method, using the samples of fly ash and bottom ash from Krabi and Mae Moh power plants. The analysis has been performed since 1981. The result obtained by this method during 1981 and 1983 shows that the quantities of U, Th and K in

Nongluck Savanonda; Ekachai Prongpunyasakul; Supapol Ratanakorn

1986-01-01

319

A simple approach to quantitative analysis using three-dimensional spectra based on selected Zernike moments.  

PubMed

A very simple approach to quantitative analysis is proposed based on the technology of digital image processing using three-dimensional (3D) spectra obtained by high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). As the region-based shape features of a grayscale image, Zernike moments with inherently invariance property were employed to establish the linear quantitative models. This approach was applied to the quantitative analysis of three compounds in mixed samples using 3D HPLC-DAD spectra, and three linear models were obtained, respectively. The correlation coefficients (R(2)) for training and test sets were more than 0.999, and the statistical parameters and strict validation supported the reliability of established models. The analytical results suggest that the Zernike moment selected by stepwise regression can be used in the quantitative analysis of target compounds. Our study provides a new idea for quantitative analysis using 3D spectra, which can be extended to the analysis of other 3D spectra obtained by different methods or instruments. PMID:23183354

Zhai, Hong Lin; Zhai, Yue Yuan; Li, Pei Zhen; Tian, Yue Li

2013-01-21

320

NASA GES DISC DAAC Data Holdings for AIRS\\/Aqua  

Microsoft Academic Search

The Atmospheric Infrared Sounder (AIRS) is a high-resolution infrared sounder on the Earth Observing System polar-orbiting platform, EOS Aqua, which was successfully launched on May 4, 2002. AIRS is closely coupled with two microwave instruments, the Advanced Microwave Sounding Unit (AMSU-A) and the Humidity Sounder for Brazil (HSB). The data products from AIRS\\/AMSU-A\\/HSB are archived and distributed at the Distributed

S. Cho; C. S. Phelps; A. K. Sharma; J. Qin

2002-01-01

321

Surgical Results of Patients with Peritoneal Carcinomatosis Treated with Cytoreductive Surgery Using a New Technique Named Aqua Dissection  

PubMed Central

During 2004 to 2011, 81, 420, and 166 patients with colorectal cancer (CRC), epithelial appendiceal neoplasm (APN), and gastric cancer (GC) with PC were treated with cytoreductive surgery (CRS) plus perioperative chemotherapy. CRS was performed by peritonectomy techniques using an aqua dissection. Results. Complete cytoreduction was done in 62/81 (76.5%), 228/420 (54.3%), and 101/166 (60.8%) of patients with CRC, APN, and GC. The main reasons of incomplete resections were involvement of all peritoneal regions and diffuse involvement of small bowel. The incidence (64%, 302/470) of CC-0 resection after introduction of an aqua dissection was significantly higher than before (42%, 82/197). A total of 41 (6.1%) patients died postoperatively. Major complication (grade 3-4 complications) occurred in 126 patients (18.9%). A reoperation was necessary in 36 patients (5.4%). By the multivariate analysis, PCI scores capable of serving as thresholds for favorable versus poor prognosis in each group and CC scores demonstrated as the independent prognostic factors. Conclusions. Peritonectomy using an aqua dissection improves the incidence of complete cytoreduction, and improves the survival of patients with PC. Patients with PCI larger than the threshold values should be treated with chemotherapy to improve the incidences of complete cytoreduction.

Yonemura, Y.; Elnemr, A.; Endou, Y.; Ishibashi, H.; Mizumoto, A.; Miura, M.; Li, Yan

2012-01-01

322

Quantitative analysis of photoactivated localization microscopy (PALM) datasets using pair-correlation analysis.  

PubMed

Pointillistic based super-resolution techniques, such as photoactivated localization microscopy (PALM), involve multiple cycles of sequential activation, imaging, and precise localization of single fluorescent molecules. A super-resolution image, having nanoscopic structural information, is then constructed by compiling all the image sequences. Because the final image resolution is determined by the localization precision of detected single molecules and their density, accurate image reconstruction requires imaging of biological structures labeled with fluorescent molecules at high density. In such image datasets, stochastic variations in photon emission and intervening dark states lead to uncertainties in identification of single molecules. This, in turn, prevents the proper utilization of the wealth of information on molecular distribution and quantity. A recent strategy for overcoming this problem is pair-correlation analysis applied to PALM. Using rigorous statistical algorithms to estimate the number of detected proteins, this approach allows the spatial organization of molecules to be quantitatively described. PMID:22447653

Sengupta, Prabuddha; Lippincott-Schwartz, Jennifer

2012-03-23

323

Multimodality comparison of quantitative volumetric analysis of the right ventricle  

Microsoft Academic Search

Real-time 3D echocardiography (RT3DE), cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) can quantify right ventricular (RV) volume and overcome the limitations 2D echocardiography that stem from the unique geometry of the right ventricle. We tested a new technique for volumetric analysis of the right ventricle designed for RT3DE, CMR and CCT (TomTec) on images obtained in RV-shaped phantoms

L. Sugeng; H. J. Nesser; L. Weinert; J. Niel; C. Ebner; R. Steringer-Mascherbauer; R. Bartolles; R. Baumann; G. Schummers; R. M. Lang; V. Mor-Avi

2009-01-01

324

Quantitative TP73 Transcript Analysis in Hepatocellular Carcinomas  

Microsoft Academic Search

Purpose: The p53 family member p73 displays signifi- cant homology to p53, but data from primary tumors dem- onstrating increased expression levels of p73 in the absence of any gene mutations argue against a classical tumor sup- pressor function. A detailed analysis of the p73 protein in tumor tissues has revealed expression of two classes of p73 isoforms. Whereas the

Thorsten Stiewe; Sebastian Tuve; Martin Peter; Andrea Tannapfel; Ahmet H. Elmaagacli; Brigitte M. Putzer

2004-01-01

325

Quantitative Analysis of Hydrogenated DLC Films by Visible Raman Spectroscopy  

Microsoft Academic Search

The correlations between properties of hydrogenated diamond like carbon films\\u000aand their Raman spectra have been investigated. The films are prepared by\\u000aplasma deposition technique, keeping different hydrogen to methane ratio during\\u000athe growth process. The hydrogen concentration, sp$^3$ content, hardness and\\u000aoptical Tauc gap of the materials have been estimated from a detail analysis of\\u000atheir Raman spectra. We

Achintya Singha; Aditi Ghosh; Nihar Ranjan Ray; Anushree Roy

2006-01-01

326

Functionally oriented and clinically feasible quantitative gait analysis method  

Microsoft Academic Search

A protocol for clinical gait analysis is described, and data from 30 normal adult female subjects are presented. Extensive\\u000a application to pathologic subjects has proven to be feasible and sufficiently accurate. The method is based on a particular\\u000a location and attachment of retro-reflective markers on the body and on a particular arrangement of four TV cameras. A motion\\u000a analyser measures

C. Frigo; M. Rabuffetti; D. C. Kerrigan; L. C. Deming; A. Pedotti

1998-01-01

327

A quantitative-experiential analysis of human emotions  

Microsoft Academic Search

A study was carried out in which participants provided written first-person present-tense descriptions of experiences of ordinary human emotions and visual analogue scale responses to intensities of desire, expectation, and positive or negative emotional feeling that were present during these experiences. Functional interrelationships found in this analysis could be described by the general equations (1) Feeling intensity=K1Desire+K2Desire×expectations5 for positive approach

Donald D. Price; James E. Barrell; James J. Barrell

1985-01-01

328

Quantitative Analysis of Calcium Spikes in Noisy Fluorescent Background  

PubMed Central

Intracellular calcium signals are studied by laser-scanning confocal fluorescence microscopy. The required spatio-temporal resolution makes description of calcium signals difficult because of the low signal-to-noise ratio. We designed a new procedure of calcium spike analysis based on their fitting with a model. The accuracy and precision of calcium spike description were tested on synthetic datasets generated either with randomly varied spike parameters and Gaussian noise of constant amplitude, or with constant spike parameters and Gaussian noise of various amplitudes. Statistical analysis was used to evaluate the performance of spike fitting algorithms. The procedure was optimized for reliable estimation of calcium spike parameters and for dismissal of false events. A new algorithm was introduced that corrects the acquisition time of pixels in line-scan images that is in error due to sequential acquisition of individual pixels along the space coordinate. New software was developed in Matlab and provided for general use. It allows interactive dissection of temporal profiles of calcium spikes from x-t images, their fitting with predefined function(s) and acceptance of results on statistical grounds, thus allowing efficient analysis and reliable description of calcium signaling in cardiac myocytes down to the in situ function of ryanodine receptors.

Janicek, Radoslav; Hotka, Matej; Zahradnikova, Alexandra; Zahradnikova, Alexandra; Zahradnik, Ivan

2013-01-01

329

The Advanced Microwave Scanning Radiometer-Earth Observing System Data Products from the Aqua Mission  

Microsoft Academic Search

The Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) is scheduled to launch on NASA's Aqua Satellite in early 2002. The Aqua mission is an important part of the NASA Earth Science Enterprise (ESE). The Aqua mission provides a multi-disciplinary study of the Earth's atmospheric, oceanic, cryospheric, and land processes and their relationship to global change. With six instruments aboard, the

D. Conway; V. Troisi; M. Marquis; R. Armstrong; J. Stroeve; J. Maslanik; Y. Axford; J. Wolfe

2001-01-01

330

Subspace techniques to remove artifacts from EEG: a quantitative analysis.  

PubMed

In this work we discuss and apply projective subspace techniques to both multichannel as well as single channel recordings. The single-channel approach is based on singular spectrum analysis(SSA) and the multichannel approach uses the extended infomax algorithm which is implemented in the opensource toolbox EEGLAB. Both approaches will be evaluated using artificial mixtures of a set of selected EEG signals. The latter were selected visually to contain as the dominant activity one of the characteristic bands of an electroencephalogram (EEG). The evaluation is performed both in the time and frequency domain by using correlation coefficients and coherence function, respectively. PMID:19163688

Teixeira, A R; Tome, A M; Lang, E W; Martins da Silva, A

2008-01-01

331

Quantitative proteomic analysis of chromatin-associated factors  

Microsoft Academic Search

A method to identify and quantify chromatin-associated proteins has been developed and applied to the analysis of changes\\u000a in chromatin-associated proteins induced by Myc oncoprotein expression in human B lymphocytes. Chromatin-enriched fractions\\u000a were isolated by differential detergent\\/salt extraction and analyzed by ICAT reagent labeling, multi-dimensional chromatography\\u000a and tandem mass spectrometry. Many known chromatin-associated regulatory factors were identified and quantified. The

Yuzuru Shiio; Robert N. Eisenman; Eugene C. Yi; Sam Donohoe; David R. Goodlett; Ruedi Aebersold

2003-01-01

332

Identifying severity of electroporation through quantitative image analysis  

NASA Astrophysics Data System (ADS)

Electroporation is the formation of reversible hydrophilic pores in the cell membrane under electric fields. Severity of electroporation is challenging to measure and quantify. An image analysis method is developed, and the initial results with a fabricated microfluidic device are reported. The microfluidic device contains integrated microchannels and coplanar interdigitated electrodes allowing low-voltage operation and low-power consumption. Noninvasive human buccal cell samples were specifically stained, and electroporation was induced. Captured image sequences were analyzed for pixel color ranges to quantify the severity of electroporation. The method can detect even a minor occurrence of electroporation and can perform comparative studies.

Morshed, Bashir I.; Shams, Maitham; Mussivand, Tofy

2011-04-01

333

Some remarks on the quantitative analysis of behavior  

PubMed Central

This paper discusses similarities between the mathematization of operant behavior and the early history of the most mathematical of sciences—physics. Galileo explored the properties of motion without dealing with the causes of motion, focusing on changes in motion. Newton's dynamics were concerned with the action of forces as causes of change. Skinner's rationale for using rate to describe behavior derived from an interest in changes in rate. Reinforcement has played the role of force in the dynamics of behavior. Behavioral momentum and maximization have received mathematical formulations in behavior analysis. Yet to be worked out are the relations between molar and molecular formulations of behavioral theory.

Marr, M. Jackson

1989-01-01

334

Quantitative spatiotemporal image analysis of fluorescein angiography in age-related macular degeneration  

NASA Astrophysics Data System (ADS)

Interpretation and analysis of retinal angiographic studies has been largely qualitative. Quantitative analysis of pathologic fundus features will facilitate interpretation and potentiate clinical studies where precise image metrology is vital. Fluorescein angiography studies of patients with age- related macular degeneration were digitized. Sequential temporal images were spatially-registered with polynomial warping algorithms, allowing for the construction of a three- dimensional (two spatial and one temporal) angiogram vector. Temporal profiles through spatially-registered, temporally- sequential pixels were computed. Characteristic temporal profiles for fundus background, retinal vasculature, retinal pigment epithelial atrophy, and choroidal neovascular (CNV) membranes were observed, allowing for pixel assignment and fundus feature quantitation. Segmentation and quantitation of fundus features including geographic atrophy and CNV is facilitated by spatio-temporal image analysis.

Berger, Jeffrey W.

1998-06-01

335

Quantitative proteomic analysis of cold-responsive proteins in rice.  

PubMed

Rice is susceptible to cold stress and with a future of climatic instability we will be unable to produce enough rice to satisfy increasing demand. A thorough understanding of the molecular responses to thermal stress is imperative for engineering cultivars, which have greater resistance to low temperature stress. In this study we investigated the proteomic response of rice seedlings to 48, 72 and 96?h of cold stress at 12-14°C. The use of both label-free and iTRAQ approaches in the analysis of global protein expression enabled us to assess the complementarity of the two techniques for use in plant proteomics. The approaches yielded a similar biological response to cold stress despite a disparity in proteins identified. The label-free approach identified 236 cold-responsive proteins compared to 85 in iTRAQ results, with only 24 proteins in common. Functional analysis revealed differential expression of proteins involved in transport, photosynthesis, generation of precursor metabolites and energy; and, more specifically, histones and vitamin B biosynthetic proteins were observed to be affected by cold stress. PMID:21433000

Neilson, Karlie A; Mariani, Michael; Haynes, Paul A

2011-03-22

336

Quantitative assessment of human body shape using Fourier analysis  

NASA Astrophysics Data System (ADS)

Fall protection harnesses are commonly used to reduce the number and severity of injuries. Increasing the efficiency of harness design requires the size and shape variation of the user population to be assessed as detailed and as accurately as possible. In light of the unsatisfactory performance of traditional anthropometry with respect to such assessments, we propose the use of 3D laser surface scans of whole bodies and the statistical analysis of elliptic Fourier coefficients. Ninety-eight male and female adults were scanned. Key features of each torso were extracted as a 3D curve along front, back and the thighs. A 3D extension of Elliptic Fourier analysis4 was used to quantify their shape through multivariate statistics. Shape change as a function of size (allometry) was predicted by regressing the coefficients onto stature, weight and hip circumference. Upper and lower limits of torso shape variation were determined and can be used to redefine the design of the harness that will fit most individual body shapes. Observed allometric changes are used for adjustments to the harness shape in each size. Finally, the estimated outline data were used as templates for a free-form deformation of the complete torso surface using NURBS models (non-uniform rational B-splines).

Friess, Martin; Rohlf, F. J.; Hsiao, Hongwei

2004-04-01

337

A quantitative comparison of functional MRI cluster analysis.  

PubMed

The aim of this work is to compare the efficiency and power of several cluster analysis techniques on fully artificial (mathematical) and synthesized (hybrid) functional magnetic resonance imaging (fMRI) data sets. The clustering algorithms used are hierarchical, crisp (neural gas, self-organizing maps, hard competitive learning, k-means, maximin-distance, CLARA) and fuzzy (c-means, fuzzy competitive learning). To compare these methods we use two performance measures, namely the correlation coefficient and the weighted Jaccard coefficient (wJC). Both performance coefficients (PCs) clearly show that the neural gas and the k-means algorithm perform significantly better than all the other methods using our setup. For the hierarchical methods the ward linkage algorithm performs best under our simulation design. In conclusion, the neural gas method seems to be the best choice for fMRI cluster analysis, given its correct classification of activated pixels (true positives (TPs)) whilst minimizing the misclassification of inactivated pixels (false positives (FPs)), and in the stability of the results achieved. PMID:15182847

Dimitriadou, Evgenia; Barth, Markus; Windischberger, Christian; Hornik, Kurt; Moser, Ewald

2004-05-01

338

Hemato-critical issues in quantitative analysis of dried blood spots: challenges and solutions.  

PubMed

Dried blood spot (DBS) sampling for quantitative determination of drugs in blood has entered the bioanalytical arena at a fast pace during the last decade, primarily owing to progress in analytical instrumentation. Despite the many advantages associated with this new sampling strategy, several issues remain, of which the hematocrit issue is undoubtedly the most widely discussed challenge, since strongly deviating hematocrit values may significantly impact DBS-based quantitation. In this review, an overview is given of the different aspects of the 'hematocrit problem' in quantitative DBS analysis. The different strategies that try to cope with this problem are discussed, along with their potential and limitations. Implementation of some of these strategies in practice may help to overcome this important hurdle in DBS assays, further allowing DBS to become an established part of routine quantitative bioanalysis. PMID:23937137

De Kesel, Pieter Mm; Sadones, Nele; Capiau, Sara; Lambert, Willy E; Stove, Christophe P

2013-08-01

339

Quantitative radiographic analysis of fiber reinforced polymer composites.  

PubMed

X-ray radiographic examination of the bone fracture healing process is a widely used method in the treatment and management of patients. Medical devices made of metallic alloys reportedly produce considerable artifacts that make the interpretation of radiographs difficult. Fiber reinforced polymer composite materials have been proposed to replace metallic alloys in certain medical devices because of their radiolucency, light weight, and tailorable mechanical properties. The primary objective of this paper is to provide a comparable radiographic analysis of different fiber reinforced polymer composites that are considered suitable for biomedical applications. Composite materials investigated consist of glass, aramid (Kevlar-29), and carbon reinforcement fibers, and epoxy and polyether-ether-ketone (PEEK) matrices. The total mass attenuation coefficient of each material was measured using clinical X-rays (50 kev). The carbon fiber reinforced composites were found to be more radiolucent than the glass and kevlar fiber reinforced composites. PMID:11261603

Baidya, K P; Ramakrishna, S; Rahman, M; Ritchie, A

2001-01-01

340

Quantitative Analysis of Single Particle Trajectories: Mean Maximal Excursion Method  

PubMed Central

An increasing number of experimental studies employ single particle tracking to probe the physical environment in complex systems. We here propose and discuss what we believe are new methods to analyze the time series of the particle traces, in particular, for subdiffusion phenomena. We discuss the statistical properties of mean maximal excursions (MMEs), i.e., the maximal distance covered by a test particle up to time t. Compared to traditional methods focusing on the mean-squared displacement we show that the MME analysis performs better in the determination of the anomalous diffusion exponent. We also demonstrate that combination of regular moments with moments of the MME method provides additional criteria to determine the exact physical nature of the underlying stochastic subdiffusion processes. We put the methods to test using experimental data as well as simulated time series from different models for normal and anomalous dynamics such as diffusion on fractals, continuous time random walks, and fractional Brownian motion.

Tejedor, Vincent; Benichou, Olivier; Voituriez, Raphael; Jungmann, Ralf; Simmel, Friedrich; Selhuber-Unkel, Christine; Oddershede, Lene B.; Metzler, Ralf

2010-01-01

341

Quantitative analysis of single particle trajectories: mean maximal excursion method.  

PubMed

An increasing number of experimental studies employ single particle tracking to probe the physical environment in complex systems. We here propose and discuss what we believe are new methods to analyze the time series of the particle traces, in particular, for subdiffusion phenomena. We discuss the statistical properties of mean maximal excursions (MMEs), i.e., the maximal distance covered by a test particle up to time t. Compared to traditional methods focusing on the mean-squared displacement we show that the MME analysis performs better in the determination of the anomalous diffusion exponent. We also demonstrate that combination of regular moments with moments of the MME method provides additional criteria to determine the exact physical nature of the underlying stochastic subdiffusion processes. We put the methods to test using experimental data as well as simulated time series from different models for normal and anomalous dynamics such as diffusion on fractals, continuous time random walks, and fractional Brownian motion. PMID:20371337

Tejedor, Vincent; Bénichou, Olivier; Voituriez, Raphael; Jungmann, Ralf; Simmel, Friedrich; Selhuber-Unkel, Christine; Oddershede, Lene B; Metzler, Ralf

2010-04-01

342

Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers  

SciTech Connect

Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.

Myers, D. R.

2011-01-01

343

Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers: Preprint  

SciTech Connect

Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.

Myers, D. R.

2011-04-01

344

Quantitative analysis of highly parallel transfection in cell microarrays  

PubMed Central

As more genomes are sequenced, we are facing the challenge of rapidly unraveling the functions of genes. To that end, cell microarrays have recently been described that transfect thousands of nucleic acids in parallel and can be used to analyze the phenotypic consequences of such perturbations. As many parameters can influence the efficacy of transfection in such a format, we describe some important features in manufacturing cell microarrays that may improve reliability and efficiency of both plasmid DNA and siRNA transfection. We have also developed image analysis software that allows automatic detection of cell clusters, quantification of transfection efficiency and levels of expression/extinction of genes. Along with cell microarrays, this bioinformatic tool should expedite functional exploration of the human genome.

Baghdoyan, Sandrine; Roupioz, Yoann; Pitaval, Amandine; Castel, David; Khomyakova, Elena; Papine, Alexandre; Soussaline, Francoise; Gidrol, Xavier

2004-01-01

345

Quantitative analysis of bloggers' collective behavior powered by emotions  

NASA Astrophysics Data System (ADS)

Large-scale data resulting from users' online interactions provide the ultimate source of information to study emergent social phenomena on the Web. From individual actions of users to observable collective behaviors, different mechanisms involving emotions expressed in the posted text play a role. Here we combine approaches of statistical physics with machine-learning methods of text analysis to study the emergence of emotional behavior among Web users. Mapping the high-resolution data from digg.com onto bipartite networks of users and their comments onto posted stories, we identify user communities centered around certain popular posts and determine emotional contents of the related comments by the emotion classifier developed for this type of text. Applied over different time periods, this framework reveals strong correlations between the excess of negative emotions and the evolution of communities. We observe avalanches of emotional comments exhibiting significant self-organized critical behavior and temporal correlations. To explore the robustness of these critical states, we design a network-automaton model on realistic network connections and several control parameters, which can be inferred from the dataset. Dissemination of emotions by a small fraction of very active users appears to critically tune the collective states.

Mitrovi?, Marija; Paltoglou, Georgios; Tadi?, Bosiljka

2011-02-01

346

Qualitative and quantitative analysis of synapses in Hirschsprung's disease.  

PubMed

In Hirschsprung's disease (HD), certain intestinal nervous plexuses are absent. Sprouting nerve endings contain different amounts of synaptophysin (SY), a protein and main constituent of acetylcholinesterase (AChE) storage compartments. Due to the lack of specific markers for synapses, a qualitative analysis of nerve endings of intestinal segments affected by HD has not yet been undertaken. For this study, resected colorectal specimens from patients with HD (n = 8, mean age 2.1 years) were investigated in parallel for AChE, SY, and content of small synaptic vesicles by biochemical, immunohistochemical, and electronmicroscopic means. In the microdissected muscular layer, reduced SY (1.4 microgram/mg total protein, normal 24 +/- 0.3) was observed. Immunohistochemistry showed in affected tissues reduced numbers of SY-positive nerve fibers and nerve endings, which in turn were thickened and distorted, in both the muscle proper and the muscularis mucosae. Combining both morphologic and biochemical findings, in HD the number of cholinergic vesicles in the remaining nerve endings seems to be increased as measured by SY, a marker molecule specific for synaptic vesicles. Our data also suggest that nerve endings in HD may contain high concentrations of cholinergic vesicles, paralleling the known high amounts of acetylcholine and AChE found in intestinal segments of patients with HD. PMID:9716672

Wiedenmann, B; Riedel, C; John, M; Ahnert-Hilger, G; Stoltenburg, G; Waldschmidt, J; von Deimling, K; Riecken, E O; Schier, F

1998-09-01

347

Quantitative Analysis Of Landslide Susceptibility: A Case Study Of Korea  

NASA Astrophysics Data System (ADS)

The aim of this study is to evaluate the susceptibility of landslides at Yongin, Janghung and Boun in Korea, using a probabilistic, statistic and neural network model. The probabilistic model is likelihood ratio, the statistic model is logistic regression and the neural network model is back propagation. Landslide locations were identified in the areas from interpretation of satellite image, aerial photographs, and field surveys. The maps such as topography, soil, forest and geology were collected and constructed into a spatial database using Geographic Information System (GIS). The factors that influence landslide occurrence, such as slope, aspect and curvature of topography, were calculated from the topographic database. Texture, material, drainage and effective soil thickness were extracted from the soil database, and type, age, diameter and density of timber were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the Landsat TM image satellite image. Landslide susceptibility was analyzed using the landslide-occurrence factors by likelihood ratio, logistic regression and neural network models . The results of the analysis were verified using the landslide location data. In addition, the results were compared between each model and each study areas. The GIS was used to analyze the vast amount of data efficiently, and statistical and neural network programs were used to maintain specificity and accuracy. The results can be used to reduce associated hazards, and to plan land use and construction.

Lee, S.; Lee, M.; Choi, J.; Yu, Y.

2003-04-01

348

[Possibilities for quantitative gait analysis in evaluation of prosthesis fit].  

PubMed

Nowadays, the fitting of a lower-limb prosthesis is done mainly on an empirical basis. The main aim of the present study was to provide objective data and presentations to support the subjective data. With the aid of a cybernetic statement, the process of fitting a prosthesis to a human subject was developed as a self-optimizing control cycle. Using this systematic scheme, the walking trial was identified as the process element of this control cycle in which the fitting proper took place. Starting with this systematic scheme, the characteristics of defined changes to the system human-prosthesis during walking were measured with the aid of a specially configured gait analysis system. For the estimation of the characteristics of the measured walking trial, a three stage parameter system based initially only on the angle, velocity and acceleration curves at the knee joint was developed. On the basis of pattern recognition routines, the parameter system permits a very high level of identification of the measurements. The identification of poor fittings not covered by the pattern recognition system is not yet satisfactory. However, with the incorporation of additional gait parameters, it will be possible to further improve the description of the gait, enabling better recognition of disturbances in the human-prosthesis system. PMID:7918976

Tscheuschner, R; Tober, H; Rosenberger, H

1994-06-01

349

Mechanistic insights from a quantitative analysis of pollen tube guidance  

PubMed Central

Background Plant biologists have long speculated about the mechanisms that guide pollen tubes to ovules. Although there is now evidence that ovules emit a diffusible attractant, little is known about how this attractant mediates interactions between the pollen tube and the ovules. Results We employ a semi-in vitro assay, in which ovules dissected from Arabidopsis thaliana are arranged around a cut style on artificial medium, to elucidate how ovules release the attractant and how pollen tubes respond to it. Analysis of microscopy images of the semi-in vitro system shows that pollen tubes are more attracted to ovules that are incubated on the medium for longer times before pollen tubes emerge from the cut style. The responses of tubes are consistent with their sensing a gradient of an attractant at 100-150 ?m, farther than previously reported. Our microscopy images also show that pollen tubes slow their growth near the micropyles of functional ovules with a spatial range that depends on ovule incubation time. Conclusions We propose a stochastic model that captures these dynamics. In the model, a pollen tube senses a difference in the fraction of receptors bound to an attractant and changes its direction of growth in response; the attractant is continuously released from ovules and spreads isotropically on the medium. The model suggests that the observed slowing greatly enhances the ability of pollen tubes to successfully target ovules. The relation of the results to guidance in vivo is discussed.

2010-01-01

350

Quantitative Analysis with Heavy Ion E-TOF ERD  

SciTech Connect

Heavy ion TOF ERD combined with energy detection (E-TOF-ERD) is a powerful analytical technique taking advantage of the following facts: the scattering cross section is usually very high ({approximately}10{sup {minus}21} cm{sup 2}/sr) compared to regular He RBS ({approximately}10{sup {minus}25} cm{sup 2}/sr), contrary to what happens with the energy resolution in ordinary surface solid barrier detectors, time resolution is almost independent of the atomic mass of the detected element, and the detection in coincidence of time and energy signals allows for the mass separation of overlapping signals with the same energy (or time of flight). Measurements on several oxides have been performed with the E-TOF-ERD set up at Sandia National Laboratories using an incident beam of 10-15 MeV Au. The information on the composition of the sample is obtained from the time domain spectrum, which is converted to energy domain, and then, using existing software codes, the analysis is performed. During the quantification of the results, they have found problems related to the interaction of the beam with the sample and to the tabulated values of the stopping powers for heavy ions.

Banks, J.C.; Doyle, B.L.; Font, A. Climent

1999-07-23

351

Quantitative analysis of scale sensitivity in geographic cellular automata  

NASA Astrophysics Data System (ADS)

Geographical Cellular Automata (GCA) approach is based on complexity theory and is widely used in geospatial modeling. A reason for the increasing attention given to GCA models is that they can easily be integrated with rasterbased GIS environment. However, the behavior of the GCA models is affected by uncertainties arising from the interaction between model elements, structures, and the quality of data sources used as model input. The objective of this study is to examine the impacts of model elements on the generated outputs of a GIS-based GCA land-use growth model using sensitivity analysis (SA) approach. The proposed SA method consists of KAPPA index with different spatial metrics. A stochastic GCA model was built to model land use change in the changsha region (Hunan,China). The transition rules were empirically derived from four Landsat-TM (30m resolution) images taken in 1996,1999, 2002 and 2005 that have been resampled to four resolutions (30, 60, 90, 120m). Five different neighbourhood configurations were considered (Moore, Von Neumann, and circular approximations of 2, 3 and 4 cell radii). Simulations were performed for each of the twenty spatial scale scenarios. Results show that spatial scale has a considerable impact on simulation dynamics in terms of both land use area and spatial structure. The spatial scale domains present in the results reveal the nonlinear relationships that link the spatial scale components to the simulation results.

Zhang, Honghui; Zeng, Yongnian; Yin, Changlin; Jin, Xiaobin; Chen, Guanghui; You, Shenjin; Zou, Bin

2008-11-01

352

Quantitative analysis of American woodcock nest and brood habitat  

USGS Publications Warehouse

Sixteen nest and 19 brood sites of American woodcock (Philohela minoI) were examined in northern lower Michigan between 15 April and 15 June 1974 to determine habitat structure associated with these sites. Woodcock hens utilized young, second-growth forest stands which were similar in species composition for both nesting and brood rearing. A multi-varIate discriminant function analysis revealed a significant (P< 0.05) difference, however, in habitat structure. Nest habitat was characterized by lower tree density (2176 trees/ha) and basal area (8.6 m2/ha), by being close to forest openings (7 m) and by being situated on dry, relatively well drained sites. In contrast, woodcock broods were located in sites that had nearly twice the tree density (3934 trees/hal and basal area (16.5 m2/ha), was located over twice as far from forest openings (18 m) and generally occurred on damp sites, near (8 m) standing water. Importance of the habitat features to the species and possible management implications are discussed.

Bourgeois, A.

1977-01-01

353

Oxidized fatty acid analysis by charge-switch derivatization, selected reaction monitoring, and accurate mass quantitation.  

PubMed

A highly sensitive, specific, and robust method for the analysis of oxidized metabolites of linoleic acid (LA), arachidonic acid (AA), and docosahexaenoic acid (DHA) was developed using charge-switch derivatization, liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI MS/MS) with selected reaction monitoring (SRM) and quantitation by high mass accuracy analysis of product ions, thereby minimizing interferences from contaminating ions. Charge-switch derivatization of LA, AA, and DHA metabolites with N-(4-aminomethylphenyl)-pyridinium resulted in a 10- to 30-fold increase in ionization efficiency. Improved quantitation was accompanied by decreased false positive interferences through accurate mass measurements of diagnostic product ions during SRM transitions by ratiometric comparisons with stable isotope internal standards. The limits of quantitation were between 0.05 and 6.0pg, with a dynamic range of 3 to 4 orders of magnitude (correlation coefficient r(2)>0.99). This approach was used to quantitate the levels of representative fatty acid metabolites from wild-type (WT) and iPLA2?(-/-) mouse liver identifying the role of iPLA2? in hepatic lipid second messenger production. Collectively, these results demonstrate the utility of high mass accuracy product ion analysis in conjunction with charge-switch derivatization for the highly specific quantitation of diminutive amounts of LA, AA, and DHA metabolites in biologic systems. PMID:23850559

Liu, Xinping; Moon, Sung Ho; Mancuso, David J; Jenkins, Christopher M; Guan, Shaoping; Sims, Harold F; Gross, Richard W

2013-07-11

354

Computerized rapid high resolution quantitative analysis of plasma lipoproteins based upon single vertical spin centrifugation.  

PubMed

A method has been developed for rapidly quantitating the cholesterol concentration of normal and certain variant lipoproteins in a large number of patients (over 240 in one week). The method employs a microcomputer interfaced to the vertical autoprofiler (VAP) described earlier (Chung et al. 1981. J. Lipid Res. 22: 1003-1014). Software developed to accomplish rapid on-line analysis of the VAP signal uses peak shapes and positions derived from prior VAP analysis of isolated authentic lipoproteins HDL, LDL, and VLDL to quantitate these species in a VAP profile. Variant lipoproteins VHDL (a species with density greater than that of HDL(3)), MDL (a species, most likely Lp(a), with density intermediate between that of HDL and LDL), and IDL are subsequently quantitated by a method combining difference calculations with curve shapes. The procedure has been validated qualitatively by negative stain electron microscopy, gradient gel electrophoresis, strip electrophoresis, chemical analysis of the lipids, radioimmunoassay of the apolipoproteins, and measurement of the density of the peak centers. It has been validated quantitatively by comparison with Lipid Research Clinic methodology for HDL-, LDL-, and VLDL-cholesterol, and for MDL- and IDL-cholesterol by comparison of the amounts of MDL or IDL predicted to be present by the method with that known to be present following standard addition to whole plasma. These validations show that the method is a rapid and accurate technique of lipoprotein analysis suitable for the routine screening of patients for abnormal amounts of normal or variant lipoproteins, as well as for use as a research tool for quantitation of changes in cholesterol content of six or seven different plasma lipoprotein fractions.-Cone, J. T., J. P. Segrest, B. H. Chung, J. B. Ragland, S. M. Sabesin, and A. Glasscock. Computerized rapid high resolution quantitative analysis of plasma lipoproteins based upon single vertical spin centrifugation. PMID:7130860

Cone, J T; Segrest, J P; Chung, B H; Ragland, J B; Sabesin, S M; Glasscock, A

1982-08-01

355

Quantitative analysis of cardiac imaging using expert systems  

NASA Astrophysics Data System (ADS)

The automatic identification of precise left ventricular endocardial surfacing using echocardiography and cardiac MRI for the quantification of ejection fraction continues to be difficult. Standard image processing techniques have not been completely successful, principally because not all edge data directly corresponds to anatomical boundaries. Trained physicians must use considerable a priori information regarding normal human anatomy to `fill in' the missing details of a typical cardiac study. In this paper, we describe a new method to identify borders within medical images that incorporates an expert system based approach. Throughout the design of this approach, we maintained the following constraints: the system must easily capture expert information from multiple experts, over a variety of cardiac image formats, be trainable on any patient, and once trained provide fast execution times. The method was initially tested on echocardiographic images. Using a series of 2D echo image sequences, an expert traced endo- and epicardial edges in order to 'teach' the computer which pixels were myocardium and which were left ventricular cavity; each identified pixel was then convolved so as to amplify correlations found between the pixel and its neighbors. The result, applied prospectively at near real time speed, identified all pixels as being myocardium, left ventricular cavity or uncertain. As a consequence, endocardial borders were generated. These borders were then used to calculate systolic and diastolic areas and an area ejection fraction which proved to be within 2% of an expert traced and calculated area ejection fraction. These findings suggest this method holds promise for the capturing of expert knowledge of 2D cardiac ultrasound interpretation, and, through preliminary testing, we have shown its potential in the segmentation of 3D cardiac MRI volume sets for subsequent analysis and display.

Dreyer, Keith J.; Simko, Joseph; Held, A. C.

1991-06-01

356

Quantitative underwater 3D motion analysis using submerged video cameras: accuracy analysis and trajectory reconstruction.  

PubMed

In this study we aim at investigating the applicability of underwater 3D motion capture based on submerged video cameras in terms of 3D accuracy analysis and trajectory reconstruction. Static points with classical direct linear transform (DLT) solution, a moving wand with bundle adjustment and a moving 2D plate with Zhang's method were considered for camera calibration. As an example of the final application, we reconstructed the hand motion trajectories in different swimming styles and qualitatively compared this with Maglischo's model. Four highly trained male swimmers performed butterfly, breaststroke and freestyle tasks. The middle fingertip trajectories of both hands in the underwater phase were considered. The accuracy (mean absolute error) of the two calibration approaches (wand: 0.96 mm - 2D plate: 0.73 mm) was comparable to out of water results and highly superior to the classical DLT results (9.74 mm). Among all the swimmers, the hands' trajectories of the expert swimmer in the style were almost symmetric and in good agreement with Maglischo's model. The kinematic results highlight symmetry or asymmetry between the two hand sides, intra- and inter-subject variability in terms of the motion patterns and agreement or disagreement with the model. The two outcomes, calibration results and trajectory reconstruction, both move towards the quantitative 3D underwater motion analysis. PMID:22435960

Silvatti, Amanda P; Cerveri, Pietro; Telles, Thiago; Dias, Fábio A S; Baroni, Guido; Barros, Ricardo M L

2012-03-21

357

Analysis of 129I in Groundwater Samples: Direct and Quantitative Results below the Drinking Water Standard  

SciTech Connect

Due to its long half-life (15.7 million years) and relatively unencumbered migration in subsurface environments, 129I has been recognized as a contaminant of concern at numerous federal, private, and international facilities. In order to understand the long-term risk associated with 129I at these locations, quantitative analysis of groundwater samples must be performed. However, the ability to quantitatively assess the 129I content in groundwater samples requires specialized extraction and sophisticated analytical techniques, which are complicated and not always available to the general scientific community. This paper highlights an analytical method capable of directly quantifying 129I in groundwater samples at concentrations below the MCL without the need for sample pre-concentration. Samples were analyzed on a Perkin Elmer ELAN DRC II ICP-MS after minimal dilution using O2 as the reaction gas. Analysis of continuing calibration verification standards indicated that the DRC mode could be used for quantitative analysis of 129I in samples below the drinking water standard (0.0057 ng/ml or 1 pCi/L). The low analytical detection limit of 129I analysis in the DRC mode coupled with minimal sample dilution (1.02x) resulted in a final sample limit of quantification of 0.0051 ng/ml. Subsequent analysis of three groundwater samples containing 129I resulted in fully quantitative results in the DRC mode, and spike recovery analyses performed on all three samples confirmed that the groundwater matrix did not adversely impact the analysis of 129I in the DRC mode. This analytical approach has been proven to be a cost-effective, high-throughput technique for the direct, quantitative analysis of 129I in groundwater samples at concentrations below the current MCL.

Brown, Christopher F.; Geiszler, Keith N.; Lindberg, Michael J.

2007-03-03

358

High-throughput automated image analysis of neuroinflammation and neurodegeneration enables quantitative assessment of virus neurovirulence.  

PubMed

Historically, the safety of live attenuated vaccine candidates against neurotropic viruses was assessed by semi-quantitative analysis of virus-induced histopathology in the central nervous system of monkeys. We have developed a high-throughput automated image analysis (AIA) for the quantitative assessment of virus-induced neuroinflammation and neurodegeneration. Evaluation of the results generated by AIA showed that quantitative estimates of lymphocytic infiltration, microglial activation, and neurodegeneration strongly and significantly correlated with results of traditional histopathological scoring. In addition, we show that AIA is a targeted, objective, accurate, and time-efficient approach that provides reliable differentiation of virus neurovirulence. As such, it may become a useful tool in establishing consistent analytical standards across research and development laboratories and regulatory agencies, and may improve the safety evaluation of live virus vaccines. The implementation of this high-throughput AIA will markedly advance many fields of research including virology, neuroinflammation, neuroscience, and vaccinology. PMID:20688036

Maximova, Olga A; Murphy, Brian R; Pletnev, Alexander G

2010-08-03

359

High-throughput automated image analysis of neuroinflammation and neurodegeneration enables quantitative assessment of virus neurovirulence  

PubMed Central

Historically, the safety of live attenuated vaccine candidates against neurotropic viruses was assessed by semi-quantitative analysis of virus-induced histopathology in the central nervous system of monkeys. We have developed a high-throughput automated image analysis (AIA) for the quantitative assessment of virus-induced neuroinflammation and neurodegeneration. Evaluation of the results generated by AIA showed that quantitative estimates of lymphocytic infiltration, microglial activation, and neurodegeneration strongly and significantly correlated with results of traditional histopathological scoring. In addition, we show that AIA is a targeted, objective, accurate, and time-efficient approach that provides reliable differentiation of virus neurovirulence. As such, it may become a useful tool in establishing consistent analytical standards across research and development laboratories and regulatory agencies, and may improve the safety evaluation of live virus vaccines. The implementation of this high-throughput AIA will markedly advance many fields of research including virology, neuroinflammation, neuroscience, and vaccinology.

Maximova, Olga A.; Murphy, Brian R.; Pletnev, Alexander G.

2010-01-01

360

Possibility of quantitative estimation of blood cell forms by the spatial-frequency spectrum analysis  

NASA Astrophysics Data System (ADS)

At present in hematology there are no quantitative estimates of such important for the cell classification parameters: cell form and nuclear form. Due to the absence of the correlation between morphological parameters and parameters measured by hemoanalyzers, both flow cytometers and computer recognition systems, do not provide the completeness of the clinical blood analysis. Analysis of the spatial-frequency spectra of blood samples (smears and liquid probes) permit the estimate the forms quantitatively. On the results of theoretical and experimental researches carried out an algorithm of the form quantitative estimation by means of SFS parameters has been created. The criteria of the quality of these estimates have been proposed. A test bench based on the coherent optical and digital processors. The received results could be applied for the automated classification of ether normal or pathological blood cells in the standard blood smears.

Spiridonov, Igor N.; Safonova, Larisa P.; Samorodov, Andrey V.

2000-05-01

361

Quantitative Intersectionality: A Critical Race Analysis of the Chicana/o Educational Pipeline  

ERIC Educational Resources Information Center

|Utilizing the critical race framework of intersectionality, this research reexamines the Chicana/o educational pipeline through a quantitative intersectional analysis. This approach disaggregates data along the intersection of race, class, gender, and citizenship status to provide a detailed portrait of the educational trajectory of…

Covarrubias, Alejandro

2011-01-01

362

Techniques for Quantitative Analysis of Software Quality throughout the SDLC: The SWEBOK Guide Coverage  

Microsoft Academic Search

This paper presents an overview of quantitative analysis techniques for software quality and their applicability during the software development life cycle (SDLC). This includes the Seven Basic Tools of Quality, Statistical Process Control, and Six Sigma, and it highlights how these techniques can be used for managing and controlling the quality of software during specification, design, implementation, testing, and maintenance.

Manar Abu Talib; Adel Khelifi; Alain Abran; Olga Ormandjieva

2010-01-01

363

Quantitative analysis of in situ wafer bowing measurements for III-nitride growth on sapphire  

Microsoft Academic Search

Wafer bowing measurements have been recently developed into an efficient tool for MOVPE and MBE process optimization. In combination with temperature and reflectance measurements they are applied for direct but mostly qualitative evaluation of III-nitride epitaxial growth processes. In this work, applying a quantitative analysis of wafer bowing throughout the full epitaxial process, we are able to trace the lattice

F. Brunner; A. Knauer; T. Schenk; M. Weyers; J.-T. Zettler

2008-01-01

364

Party Strategy and Media Bias: A Quantitative Analysis of the 2005 UK Election Campaign  

Microsoft Academic Search

This article investigates the current state of press partisanship in the UK. Utilizing content analysis data from the 2005 General Election campaign, recent hypotheses about press dealignment are tested with quantitative methods. Partisan tendencies in reporting are measured in terms of coverage bias, statement bias, and agenda bias. As the governing party, Labour benefits from coverage bias in all papers,

Heinz Brandenburg

2006-01-01

365

Forty Years of the "Journal of Librarianship and Information Science": A Quantitative Analysis, Part I  

ERIC Educational Resources Information Center

|This paper reports on the first part of a two-part quantitative analysis of volume 1-40 (1969-2008) of the "Journal of Librarianship and Information Science" (formerly the "Journal of Librarianship"). It provides an overview of the current state of LIS research journal publishing in the UK; a review of the publication and printing history of…

Furner, Jonathan

2009-01-01

366

Quantitative Analysis and Rating Considerations of a Doubly Fed Induction Generator for Wind Energy Conversion Systems  

Microsoft Academic Search

This paper presents a quantitative analysis of the advantages of a grid connected doubly fed induction generator (DFIG) for wind energy conversion systems (WECS) over the other available variable speed WECS. The WEC system includes back-to-back connected PWM voltage source converters (VSC) in the rotor circuit of the DFIG. The control strategy implemented is - unity power factor operation of

Vijay Chand Ganti; Bhim Singh

2010-01-01

367

QUANTITATIVE ANALYSIS OF SHADOW EFFECTS IN HIGH-RESOLUTION IMAGES OF URBAN AREAS  

Microsoft Academic Search

Shadow effects have drawn much attention by researchers with increasing use of high-resolution remote sensing images of urban areas. For correction or compensation to pixels that falling in shadow areas due to the existence of vertically standing objects such as buildings and trees, quantitative analysis of shadow effects is essential. In this paper, we proposed an object-based approach for predicting,

Qingming Zhan; Wenzhong Shi; Yinghui Xiao

368

The state of applications of quantitative analysis techniques to construction economics and management (1983 to 2006)  

Microsoft Academic Search

With increasing complexity of construction industry problems, researchers are experimenting with computationally rigorous techniques with the aim of seeking innovative solutions. In order to trace the applications of quantitative analysis techniques to research in the two fields of construction economics and construction management for both conventional and AI techniques, the methodology involves compiling all the relevant papers from the top

Goh Bee Hua

2008-01-01

369

Use of low-energy gamma ray scattering and X-ray fluorescence in quantitative analysis  

Microsoft Academic Search

The limits of employing Rayleigh (R) and Compton (C) scattering of low energy gamma radiation for quantitative analysis are discussed. It is shown in which approximation the value of the R\\/C ratio can be considered to be a linear function of the weight fraction for binary alloys. Experimental evidence for an anomalous dispersion effect in the Rayleigh cross sections is

Carlo Bui; Mario Milazzo; Massimo Monichino

1987-01-01

370

A Colorimetric Analysis Experiment Not Requiring a Spectrophotometer: Quantitative Determination of Albumin in Powdered Egg White  

ERIC Educational Resources Information Center

|A general science experiment for high school chemistry students might serve as an excellent review of the concepts of solution preparation, solubility, pH, and qualitative and quantitative analysis of a common food product. The students could learn to use safe laboratory techniques, collect and analyze data using proper scientific methodology and…

Charlton, Amanda K.; Sevcik, Richard S.; Tucker, Dorie A.; Schultz, Linda D.

2007-01-01

371

Quantitative Analysis of Organic Compounds: A Simple and Rapid Method for Use in Schools  

ERIC Educational Resources Information Center

Describes the procedure for making a quantitative analysis of organic compounds suitable for secondary school chemistry classes. Using the Schoniger procedure, the organic compound, such as PVC, is decomposed in a conical flask with oxygen. The products are absorbed in a suitable liquid and analyzed by titration. (JR)

Schmidt, Hans-Jurgen

1973-01-01

372

Quantitative and Qualitative Analysis of Nutrition and Food Safety Information in School Science Textbooks of India  

ERIC Educational Resources Information Center

|Objective: To assess quantity and quality of nutrition and food safety information in science textbooks prescribed by the Central Board of Secondary Education (CBSE), India for grades I through X. Design: Content analysis. Methods: A coding scheme was developed for quantitative and qualitative analyses. Two investigators independently coded the…

Subba Rao, G. M.; Vijayapushapm, T.; Venkaiah, K.; Pavarala, V.

2012-01-01

373

Validation of a new quantitative coronary angiography analysis system used to evaluate densitometric lumen remodelling  

Microsoft Academic Search

Arterial lumen volume, determined by sequential coronary angiography, could have advantages over more commonly used variables (such as percent stenosis or minimal lumen diameter) as a primary endpoint in clinical trials evaluating post-angioplasty restenosis or atherosclerotic plaque progression. We validated a quantitative coronary angiography analysis (QCA) system aimed at measuring lumen volume from coronary angiography films by a densitometric method.

Michel Lièvre; Gérard Finet; Jean Maupas

1997-01-01

374

Coronary arteriography for quantitative analysis: Experimental and clinical comparison of cinefilm and video recordings  

Microsoft Academic Search

Although use of videotape for the recording of coronary angiograms continues to grow, the validity of quantitative coronary angiographic analysis of video images remains unknown. To estimate the realibility of angiographic images recorded on videotapes, experimental and clinical angiograms were recorded simultaneously on both 35 mm cinefilm and super-VHS videotape with normal images and with spatial filtering of the images

Yukio Ozaki; David Keane; Jean Paul Herrman; David Foley; Jfirgen Haase; Ad den Boer; Carlo di Mario; Patrick W. Serruys

1995-01-01

375

Quantitative Coronary Analysis Medical Image Processing Improved by Combining Wavelet Edge Detection and Segmentation  

Microsoft Academic Search

The quantitative coronary analysis (QCA) is a useful method for physicians to diagnose heart artery stenosis. So the precision of coronary angiography image quality is very definite important. In this study we present a precision 2-D image processing method that combines gradient segmentation and region segmentation approaches with an entropy maximization procedure. This method allows us to utilize all available

Tsair-Fwu Lee; Chang-Yu Lee; Pei-Ju Chao; Chieh Lee; Chang-Yu Wang; Chun-Hsiung Fang

2009-01-01

376

QUANTITATIVE PCR ANALYSIS OF MOLDS IN THE DUST FROM HOMES OF ASTHMATIC CHILDREN IN NORTH CAROLINA  

EPA Science Inventory

The vacuum bag (VB) dust was analyzed by mold specific quantitative PCR. These results were compared to the analysis survey calculated for each of the homes. The mean and standard deviation (SD) of the ERMI values in the homes of the NC asthmatic children was 16.4 (6.77), compa...

377

Improved calculation of the backscattering factor for quantitative analysis by Auger electron spectroscopy  

Microsoft Academic Search

Based on a Monte Carlo simulation method, an improved calculation of the backscattering factor in quantitative analysis by Auger electron spectroscopy has been performed by integrating several aspects of recent progresses in the related fields. The calculation used a general definition of backscattering factor, more accurate ionization cross section, up-to-date Monte Carlo model of electron inelastic scattering, and a large

Z. J. Ding; W. S. Tan; Y. G. Li

2006-01-01

378

Quantitative fluid inclusion gas analysis of airburst, nuclear, impact and fulgurite glasses  

Microsoft Academic Search

We present quantitative fluid inclusion gas analysis on a suite of violently-formed glasses. We used the incremental crush mass spectrometry method (Norman & Blamey, 2001) to analyze eight pieces of Libyan Desert Glass (LDG). As potential analogues we also analyzed trinitite, three impact crater glasses, and three fulgurites. The 'clear' LDG has the lowest CO content and O\\/Ar ratios are

John Parnell; Horton E. Newsom; Nigel J. F. Blamey; Mark Bruce Elrick Boslough

2010-01-01

379

Quantitative Analysis of Organic Compounds: A Simple and Rapid Method for Use in Schools  

ERIC Educational Resources Information Center

|Describes the procedure for making a quantitative analysis of organic compounds suitable for secondary school chemistry classes. Using the Schoniger procedure, the organic compound, such as PVC, is decomposed in a conical flask with oxygen. The products are absorbed in a suitable liquid and analyzed by titration. (JR)|

Schmidt, Hans-Jurgen

1973-01-01

380

Systematic review of quantitative clinical gait analysis in patients with dementia  

Microsoft Academic Search

Summary. Introduction: Diminished mobility often accompanies dementia and has a great impact on independence and quality of life. New treatment strategies for dementia are emerging, but the effects on gait remains to be studied objectively. In this review we address the general effects of dementia on gait as revealed by quantitative gait analysis. Methods: A systematic literature search with the

M. B. van Iersel; W. Hoefsloot; M. Munneke; B. R. Bloem; M. G. M. Olde Rikkert

2004-01-01

381

Description of CORSET: a computer program for quantitative x-ray fluorescence analysis  

Microsoft Academic Search

Quantitative x-ray fluorescence analysis requires a method of correcting for absorption and secondary fluorescence effects due to the sample matrix. The computer program CORSET carries out these corrections without requiring a knowledge of the spectral distribution of the x-ray source, and only requires one standard per element or one standard containing all the elements. Sandia's version of CORSET has been

Stohl

1980-01-01

382

Quantitative analysis and molecular identification of bifidobacteria strains in probiotic milk products  

Microsoft Academic Search

The aim of the present study was to evaluate an agar medium for the quantitative analysis of bifidobacteria in probiotic milk products on the market, and to investigate the identities of active strains. For this purpose, three sour milk products and a soft cheese brand were each analysed ten times with Wilkins-Chalgren agar (WCA) supplemented with mupirocin, and with MRS

Marius Grand; Marianne Küffer; Andreas Baumgartner

2003-01-01

383

SWOT ANALYSIS TECHNIQUE AS A QUANTITATIVE TOOL FOR ADAPTIVE MANAGEMENT ON TRANSBOUNDARY RIVER BASINS  

Microsoft Academic Search

Most conflicts between countries, originate from issues regarding the quantity and quality of shared water resources. During the last decades, many tools and models for river basin management have been developed according to the international and European law, conventions and other agreements. The proposed methodology is a quantitative outlook of the popular SWOT analysis. The technique suggested in this article

Christina Mitsiani

384

Western blot analysis with quantum dot fluorescence technology: a sensitive and quantitative method for multiplexed proteomics  

Microsoft Academic Search

Western or immunoblotting analysis of protein expression in cells and tissues has been the major analytical tool for assessing molecular biological functions in basic cell biological research, pathology and drug discovery and development. With the rapid growth of our understanding of gene and protein expression pathways and limited supplies of tissue, there is an ever-increasing need for more sensitive, quantitative

Richard L Ornberg; Theresa F Harper; Hongjian Liu

2005-01-01

385

Quantitative analysis of melt elongational behavior of LLDPE\\/LDPE blends  

Microsoft Academic Search

Shear and elongational data of blends of linear (LLDPE) and branched (LDPE) polyethylene are reported. Blends show thermo-rheological complex behavior. Also, in unidirectional shear or elongational flow, the linear-viscoelastic deformation regime of the blends is significantly reduced, and the terminal relaxation times of the blends are shifted in the direction of the LDPE homopolymer. Quantitative analysis of elongational viscosity data

Manfred H. Wagner; Saeid Kheirandish; Masayuki Yamaguchi

2004-01-01

386

Quantitative analysis of the epithelial lining architecture in radicular cysts and odontogenic keratocysts  

Microsoft Academic Search

BACKGROUND: This paper describes a quantitative analysis of the cyst lining architecture in radicular cysts (of inflammatory aetiology) and odontogenic keratocysts (thought to be developmental or neoplastic) including its 2 counterparts: solitary and associated with the Basal Cell Naevus Syndrome (BCNS). METHODS: Epithelial linings from 150 images (from 9 radicular cysts, 13 solitary keratocysts and 8 BCNS keratocysts) were segmented

Gabriel Landini

2006-01-01

387

Quantitative Thermal Analysis of Poly(butylene Terephthalate) by Temperature-Modulated Differential Scanning Calorimetry  

Microsoft Academic Search

Quantitative thermal analysis is performed on poly(butylene terephthalate), PBT, between 5 and 600 K based on the measured heat capacity by adiabatic calorimertry, standard differential scanning calorimetry (DSC) and temperature-modulated differential scanning calorimetry (TMDSC). Based on the new data, the low temperature heat capacity is linked to the vibrational spectrum, using the ATHAS method to calculate the solid heat capacity

M. Pyda; E. Nowak-Pyda; B. Wunderlich

2004-01-01

388

A quantitative comparison of vector magnetic field measurement and analysis techniques  

Microsoft Academic Search

We make a quantitative comparison between spectral vs filter measurement and analysis techniques for extraction of solar vector magnetic fields from polarimetric data using as a basis the accurately calibrated, high angular resolution. Stokes profile data from the Advanced Stokes Polarimeter. It is shown that filter-based measurements deliver qualitative images of the field alignment for sunspots that are visually similar

B. W. Lites; V. Martinez Pillet; A. Skumanich

1994-01-01

389

A quantitative comparison of vector magnetic field measurement and analysis techniques  

Microsoft Academic Search

We make a quantitative comparison between spectral vs filter measurement and analysis techniques for extraction of solar vector magnetic fields from polarimetric data using as a basis the accurately calibrated, high angular resolution Stokes profile data from the Advanced Stokes Polarimeter. It is shown that filter-based measurements deliver qualitative images of the field alignment for sunspots that are visually similar

B. W. Lites; V. Martínez Pillet; A. Skumanich

1994-01-01

390

Incorporation of elements of quantitative risk analysis in the HACCP system  

Microsoft Academic Search

Foodborne bacterial diseases cause considerable morbidity and mortality throughout the world. Preventive measures such as good manufacturing practices (GMP), supplemented by the hazard analysis critical control point (HACCP) system, have been introduced as a means of ensuring the production of safe food. However, their use does not necessarily provide quantitative information on the risks associated with the consumption of a

S. Notermans; G. C. Mead

1996-01-01

391

Seismic risk of atmospheric storage tanks in the framework of quantitative risk analysis  

Microsoft Academic Search

The quantitative risk assessment of industrial facilities is based on integrated procedures to quantify human, environmental and economical losses related to relevant accidents. Accordingly, seismic risk analysis has to be integrated in order to obtain reliable results.In this work, some considerations regarding the intensity and probability of occurrence of earthquakes and the vulnerability of atmospheric storage tanks subjected to seismic

E. Salzano; I. Iervolino; G. Fabbrocino

2003-01-01

392

A Quantitative and Qualitative Analysis of Japanese Television News Coverage of the Beijing Olympics Opening Ceremony  

Microsoft Academic Search

This paper presents the results of quantitative and qualitative analysis carried out on Japanese television coverage of the Beijing Olympics. In the first half of 2008, Japanese television news coverage of China focused on negative news. However, this kind of news was overshadowed as soon as the Beijing Olympics began, with subsequent China coverage focusing overwhelmingly on Beijing Olympics-related news.

Masaki Naka; Naomi Kobayashi

2010-01-01

393

Assessing undergraduate use of electronic resources: A quantitative analysis of works cited  

Microsoft Academic Search

This study reports undergraduate use of electronic resources as measured through the quantitative analysis of 291 student bibliographies submitted for courses in ten undergraduate institutions in the Greater Philadelphia Area. The authors found relatively few citations of electronic sources (7%) and agreat deal of confusion about the citation format itself. No relationship was found between instruction in the use of

Debbie Malone; Carol Videon

1997-01-01

394

Quantitative analysis of untreated hair samples for monitoring human exposure to heavy metals  

Microsoft Academic Search

The method of quantitative analysis for untreated hair samples, which we developed three years ago, has proved to be quite useful for investigating environments contaminated by certain toxic elements. In the present work, the experimental conditions are improved. Loss of certain elements owing to irradiation damage, which has remained as one of the experimental uncertainties, was examined. It was found

K. Sera; S. Futatsugawa; S. Murao

2002-01-01

395

Queueing Petri Nets-A formalism for the combined qualitative and quantitative analysis of systems  

Microsoft Academic Search

System analysis is often needed with respect to both qualitative and quantitative aspects. In recent decades, several formalisms have been developed that attempt to combine these aspects in one description. Present emphasis is on stochastic Petri nets. One disadvantage of these formalisms is the difficulties when describing scheduling strategies with Petri net elements. A new version of queuing Petri nets

Falko Bause

1993-01-01

396

A Quantitative Categorical Analysis of Metadata Elements in Image-Applicable Metadata Schemas.  

ERIC Educational Resources Information Center

|Reports on a quantitative categorical analysis of metadata elements in the Dublin Core, VRA (Visual Resource Association) Core, REACH (Record Export for Art and Cultural Heritage), and EAD (Encoded Archival Description) metadata schemas, all of which can be used for organizing and describing images. Introduces a new schema comparison methodology…

Greenberg, Jane

2001-01-01

397

An Assessment of Software Solutions for the Analysis of Mass Spectrometry Based Quantitative Proteomics Data  

Microsoft Academic Search

Over the past decade, a series of experimental strategies for mass spectrometry based quantitative proteomics and corresponding computational methodology for the processing of the resulting data have been generated. We provide here an overview of the main quantification principles and available software solutions for the analysis of data generated by liquid chromatography coupled to mass spectrometry (LC-MS). Three conceptually different

Lukas N. Mueller; Mi-Youn Brusniak; D. R. Mani; Ruedi Aebersold

2008-01-01

398

Solar aqua-ammonia absorption refrigerator simulation  

Microsoft Academic Search

Thermodynamic analysis of an Ammonia-water absorption refrigeration cycle performance, using solar energy in the generator, is simulated by means of a PC program. The economic feasibility of the system for ice production is studied in two southern locations of Spain. For the solar energy collection unit, a Compound Parabolic Collector (CPC) is considered. The optimal value of the Coefficient of

E. Elegido; J. M. De Juana; M. A. Herrero

1991-01-01

399

Quantitative analysis of ciliary beating in primary ciliary dyskinesia: a pilot study  

PubMed Central

Background Primary ciliary dyskinesia (PCD) is a rare congenital respiratory disorder characterized by abnormal ciliary motility leading to chronic airway infections. Qualitative evaluation of ciliary beat pattern based on digital high-speed videomicroscopy analysis has been proposed in the diagnosis process of PCD. Although this evaluation is easy in typical cases, it becomes difficult when ciliary beating is partially maintained. We postulated that a quantitative analysis of beat pattern would improve PCD diagnosis. We compared quantitative parameters with the qualitative evaluation of ciliary beat pattern in patients in whom the diagnosis of PCD was confirmed or excluded. Methods Nasal nitric oxide measurement, nasal brushings and biopsies were performed prospectively in 34 patients with suspected PCD. In combination with qualitative analysis, 12 quantitative parameters of ciliary beat pattern were determined on high-speed videomicroscopy recordings of beating ciliated edges. The combination of ciliary ultrastructural abnormalities on transmission electron microscopy analysis with low nasal nitric oxide levels was the “gold standard” used to establish the diagnosis of PCD. Results This “gold standard” excluded PCD in 15 patients (non-PCD patients), confirmed PCD in 10 patients (PCD patients) and was inconclusive in 9 patients. Among the 12 parameters, the distance traveled by the cilium tip weighted by the percentage of beating ciliated edges presented 96% sensitivity and 95% specificity. Qualitative evaluation and quantitative analysis were concordant in non-PCD patients. In 9/10 PCD patients, quantitative analysis was concordant with the “gold standard”, while the qualitative evaluation was discordant with the “gold standard” in 3/10 cases. Among the patients with an inconclusive “gold standard”, the use of quantitative parameters supported PCD diagnosis in 4/9 patients (confirmed by the identification of disease-causing mutations in one patient) and PCD exclusion in 2/9 patients. Conclusions When the beat pattern is normal or virtually immotile, the qualitative evaluation is adequate to study ciliary beating in patients suspected for PCD. However, when cilia are still beating but with moderate alterations (more than 40% of patients suspected for PCD), quantitative analysis is required to precise the diagnosis and can be proposed to select patients eligible for TEM.

2012-01-01

400

Quantitative cDNA-AFLP analysis for genome-wide expression studies  

Microsoft Academic Search

An improved cDNA-AFLP method for genome-wide expression analysis has been developed. We demonstrate that this method is an efficient tool for quantitative transcript profiling and a valid alternative to microarrays. Unique transcript tags, generated from reverse-transcribed messenger RNA by restriction enzymes, were screened through a series of selective PCR amplifications. Based on in silico analysis, an enzyme combination was chosen

P. Breyne; R. Dreesen; B. Cannoot; D. Rombaut; K. Vandepoele; S. Rombauts; R. Vanderhaeghen; D. Inzé; M. Zabeau

2003-01-01

401

Variability of quantitative coronary angiography: an evaluation of on-site versus core laboratory analysis  

Microsoft Academic Search

To assess the validity of locally performed off-line quantitative coronary angiography (QCA) measurement in clinical trials, we carried out a comparative study between on-site QCA analysis and analysis performed at an independent external core laboratory. One local operator analyzed the pre, post and follow-up angiograms of 116 patients participating in the Stenting in Small Coronary Arteries Study (SISCA) prior to

Rasmus Moer; Anton W. M. van Weert; Yngvar Myreng; Per Mølstad

2003-01-01

402

Quantitative EEG analysis of REM sleep in children with Down syndrome  

Microsoft Academic Search

Purpose: The aim was to compare quantitative EEG analysis of REM sleep in children with Down syndrome (DS) and normal age-matched controls. Material and methods: Twenty-one channel EEG of 21 patients with Down syndrome and 21 normal children, with ages ranging from 1 to 8 years, were submitted to quanti- tative analysis EEG of discharge-free epochs. The signals were recorded

Sobaniec W

2005-01-01

403

The Replacement of Cytogenetic Analysis by Direct Chorionic Villi Sampling Preparation with Quantitative Fluorescence PCR  

Microsoft Academic Search

Aim: The aim of this study is to assess the replacement of chromosomal analysis of chorionic villi (CV) direct preparation samples (DIR) by quantitative fluorescence PCR (QF-PCR) and to determine its advantages in routine prenatal diagnosis. Methods: From a total of 4,020 CV samples, rapid results were obtained either by conventional cytogenetic analysis of DIR in 2,770 samples, or by

S. Christopoulou; G. Christopoulou; A. Hatzaki; A. Hatzipouliou; J. Donoghue; M. Karkaletsi; P. Kaminopetros; S. Sifakis; V. Velissariou

2009-01-01

404

A quantitative ratiometric sensor for time-resolved analysis of auxin dynamics  

PubMed Central

Time-resolved quantitative analysis of auxin-mediated processes in plant cells is as of yet limited. By applying a synergistic mammalian and plant synthetic biology approach, we have developed a novel ratiometric luminescent biosensor with wide applicability in the study of auxin metabolism, transport, and signalling. The sensitivity and kinetic properties of our genetically encoded biosensor open new perspectives for the analysis of highly complex auxin dynamics in plant growth and development.

Wend, Sabrina; Bosco, Cristina Dal; Kampf, Michael M.; Ren, Fugang; Palme, Klaus; Weber, Wilfried; Dovzhenko, Alexander; Zurbriggen, Matias D.

2013-01-01

405

ELABORATION OF NOT LARGE MOBILE MODULAR INSTALLATION ''AQUA - EXPRESS'' (300 L/H) FOR LRW CLEANING  

SciTech Connect

Mobile modular installation ''Aqua-Express'' is a liquid low level and intermediate level radioactive waste (LL&ILRW) treatment facility, intended for not large research centers and other organizations, which activity causes the formation of a few quantity (up to 500 m3/year) of low and intermediate level radioactive waste water. Mobile modular installation ''Aqua-Express'' has the following features: (1) filtration, sorption and ultrafiltration units are used for LL&ILRW purification; (2) installation ''Aqua-Express'' consists of a cascade of three autonomous aqueous liquid waste-purifying installations; (3) installation ''Aqua-Express'' is a mobile installation; the installation can be transported by car, train, ship, or plane, as well as placed in a standard transport (sea or railway) container; (4) installation ''Aqua-Express'' does not includes any technological equipment for conditioning the secondary radioactive waste. Productivity of the installation ''Aqua-Express'' by purified water depends on composition of the initial liquid waste and makes up to 300 l/h. In present report is described the design of installation ''Aqua-Express'', theory of LRW purification in the installation ''Aqua-Express'' and some results of its use at cleaning real radioactive waters at State unitary enterprise - MosNPO ''Radon''.

Karlin, Yurii; Dmitriev, Sergey; Iljin, Vadim; Ojovan, Mihail; Burcl, Rudolf

2003-02-27

406

Quantitative analysis of the effectiveness of pediatric therapy. Emphasis on the neurodevelopmental treatment approach.  

PubMed

We investigated the effectiveness of neurodevelopmental treatment when used both in isolation and in combination with other developmental therapies. The data were analyzed using recently developed methods of quantitatively synthesizing research results in which the literature review process is regarded as a unique type of research. Our analysis revealed that the subjects who received NDT performed slightly better than the control-comparison subjects who did not receive the intervention. The study outcomes are discussed in relation to several design variables and study characteristics associated with subject performance. The advantages and limitations of quantitative reviewing are identified briefly, and the potential use of the procedures in clinical research is emphasized. PMID:2941772

Ottenbacher, K J; Biocca, Z; DeCremer, G; Gevelinger, M; Jedlovec, K B; Johnson, M B

1986-07-01

407

Functionalized magnetic nanoparticles for the detection and quantitative analysis of cell surface antigen.  

PubMed

Cell surface antigens as biomarkers offer tremendous potential for early diagnosis, prognosis, and therapeutic response in a variety of diseases such as cancers. In this research, a simple, rapid, accurate, inexpensive, and easily available in vitro assay based on magnetic nanoparticles and magnetic cell separation principle was applied to identify and quantitatively analyze the cell surface antigen expression in the case of prostate cancer cells. Comparing the capability of the assay with flow cytometry as a gold standard method showed similar results. The results showed that the antigen-specific magnetic cell separation with antibody-coated magnetic nanoparticles has high potential for quantitative cell surface antigen detection and analysis. PMID:23484112

Shahbazi-Gahrouei, Daryoush; Abdolahi, Mohammad; Zarkesh-Esfahani, Sayyed Hamid; Laurent, Sophie; Sermeus, Corine; Gruettner, Cordula

2012-12-31

408

Quantitative analysis of the mixtures of illicit drugs using terahertz time-domain spectroscopy  

NASA Astrophysics Data System (ADS)

A method was proposed to quantitatively inspect the mixtures of illicit drugs with terahertz time-domain spectroscopy technique. The mass percentages of all components in a mixture can be obtained by linear regression analysis, on the assumption that all components in the mixture and their absorption features be known. For illicit drugs were scarce and expensive, firstly we used common chemicals, Benzophenone, Anthraquinone, Pyridoxine hydrochloride and L-Ascorbic acid in the experiment. Then illicit drugs and a common adulterant, methamphetamine and flour, were selected for our experiment. Experimental results were in significant agreement with actual content, which suggested that it could be an effective method for quantitative identification of illicit drugs.

Jiang, Dejun; Zhao, Shusen; Shen, Jingling

2008-03-01

409

Quantitative trait loci analysis of powdery mildew disease resistance in the Arabidopsis thaliana accession kashmir-1.  

PubMed Central

Powdery mildew diseases are economically important diseases, caused by obligate biotrophic fungi of the Erysiphales. To understand the complex inheritance of resistance to the powdery mildew disease in the model plant Arabidopsis thaliana, quantitative trait loci analysis was performed using a set of recombinant inbred lines derived from a cross between the resistant accession Kashmir-1 and the susceptible accession Columbia glabrous1. We identified and mapped three independent powdery mildew quantitative disease resistance loci, which act additively to confer disease resistance. The locus with the strongest effect on resistance was mapped to a 500-kbp interval on chromosome III.

Wilson, I W; Schiff, C L; Hughes, D E; Somerville, S C

2001-01-01

410

Qualitative and quantitative analysis of stability and instability dynamics of positive lattice solitons.  

PubMed

We present a unified approach for qualitative and quantitative analysis of stability and instability dynamics of positive bright solitons in multidimensional focusing nonlinear media with a potential (lattice), which can be periodic, periodic with defects, quasiperiodic, single waveguide, etc. We show that when the soliton is unstable, the type of instability dynamic that develops depends on which of two stability conditions is violated. Specifically, violation of the slope condition leads to a focusing instability, whereas violation of the spectral condition leads to a drift instability. We also present a quantitative approach that allows one to predict the stability and instability strength. PMID:18999546

Sivan, Y; Fibich, G; Ilan, B; Weinstein, M I

2008-10-02

411

The quantitative discrimination between shrinkage and gas microporosity in cast aluminum alloys using spatial data analysis  

SciTech Connect

Microporosity in cast aluminum alloys may originate from hydrogen gas evolution, microshrinkage, or a combination of both. A spatial analysis method for the quantitative discrimination between shrinkage and gas porosity is presented and explained. It is shown that shrinkage pores can be selected and analyzed separately from gas pores by nearest-neighbor analysis. The principles of spatial statistics are discussed, and the types of spatial point patterns, complete spatial randomness, and nearest-neighbor cluster analysis are reviewed with respect to microporosity analysis. The pore distribution of a cast Al-7% Si (A356) foundry alloy is used as an example.

Anson, J.P.; Gruzleski, J.E.

1999-11-01

412

Quantitative image analysis for the characterization of microbial aggregates in biological wastewater treatment: a review.  

PubMed

Quantitative image analysis techniques have gained an undeniable role in several fields of research during the last decade. In the field of biological wastewater treatment (WWT) processes, several computer applications have been developed for monitoring microbial entities, either as individual cells or in different types of aggregates. New descriptors have been defined that are more reliable, objective, and useful than the subjective and time-consuming parameters classically used to monitor biological WWT processes. Examples of this application include the objective prediction of filamentous bulking, known to be one of the most problematic phenomena occurring in activated sludge technology. It also demonstrated its usefulness in classifying protozoa and metazoa populations. In high-rate anaerobic processes, based on granular sludge, aggregation times and fragmentation phenomena could be detected during critical events, e.g., toxic and organic overloads. Currently, the major efforts and needs are in the development of quantitative image analysis techniques focusing on its application coupled with stained samples, either by classical or fluorescent-based techniques. The use of quantitative morphological parameters in process control and online applications is also being investigated. This work reviews the major advances of quantitative image analysis applied to biological WWT processes. PMID:23716077

Costa, J C; Mesquita, D P; Amaral, A L; Alves, M M; Ferreira, E C

2013-05-29

413

Quantitative Assessment of In-solution Digestion Efficiency Identifies Optimal Protocols for Unbiased Protein Analysis.  

PubMed

The majority of mass spectrometry-based protein quantification studies uses peptide-centric analytical methods and thus strongly relies on efficient and unbiased protein digestion protocols for sample preparation. We present a novel objective approach to assess protein digestion efficiency using a combination of qualitative and quantitative liquid chromatography-tandem MS methods and statistical data analysis. In contrast to previous studies we employed both standard qualitative as well as data-independent quantitative workflows to systematically assess trypsin digestion efficiency and bias using mitochondrial protein fractions. We evaluated nine trypsin-based digestion protocols, based on standard in-solution or on spin filter-aided digestion, including new optimized protocols. We investigated various reagents for protein solubilization and denaturation (dodecyl sulfate, deoxycholate, urea), several trypsin digestion conditions (buffer, RapiGest, deoxycholate, urea), and two methods for removal of detergents before analysis of peptides (acid precipitation or phase separation with ethyl acetate). Our data-independent quantitative liquid chromatography-tandem MS workflow quantified over 3700 distinct peptides with 96% completeness between all protocols and replicates, with an average 40% protein sequence coverage and an average of 11 peptides identified per protein. Systematic quantitative and statistical analysis of physicochemical parameters demonstrated that deoxycholate-assisted in-solution digestion combined with phase transfer allows for efficient, unbiased generation and recovery of peptides from all protein classes, including membrane proteins. This deoxycholate-assisted protocol was also optimal for spin filter-aided digestions as compared with existing methods. PMID:23792921

León, Ileana R; Schwämmle, Veit; Jensen, Ole N; Sprenger, Richard R

2013-06-21

414

Purification and characterization of phycocyanin from the blue-green alga Aphanizomenon flos-aquae.  

PubMed

Aphanizomenon flos-aquae (AFA) is a blue-green alga and represents a nutrient-dense food source. In this study the presence of phycocyanin (PC), a blue protein belonging to the photosynthetic apparatus, has been demonstrated in AFA. An efficient method for its separation has been set up: PC can be purified by a simple single step chromatographic run using a hydroxyapatite column (ratio A620/A280 of 4.78), allowing its usage for health-enhancing properties while eliminating other aspecific algal components. Proteomic investigation and HPLC analysis of purified AFA phycobilisomes revealed that, contrary to the well-characterized Synechocystis and Spirulina spp., only one type of biliprotein is present in phycobilisomes: phycocyanins with no allo-phycocyanins. Two subunit polypeptides of PC were also separated: the beta subunit containing two bilins as chromophore and the alpha subunit containing only one. PMID:16266834

Benedetti, Serena; Rinalducci, Sara; Benvenuti, Francesca; Francogli, Sonia; Pagliarani, Silvia; Giorgi, Luca; Micheloni, Mauro; D'Amici, Gian Maria; Zolla, Lello; Canestrari, Franco

2005-11-02

415

Stable isotope labeling of mammals (SILAM) for in vivo quantitative proteomic analysis.  

PubMed

Metabolic labeling of rodent proteins with ¹?N, a heavy stable isotope of nitrogen, provides an efficient way for relative quantitation of differentially expressed proteins. Here we describe a protocol for metabolic labeling of rats with an ¹?N-enriched spirulina diet. As a case study, we also demonstrate the application of ¹?N-enriched tissue as a common internal standard in quantitative analysis of differentially expressed proteins in neurodevelopment in rats at two different time points, postnatal day 1 and 45. We briefly discuss the bioinformatics tools, ProLucid and Census, which can easily be used in a sequential manner to identify and quantitate relative protein levels on a proteomic scale. PMID:23523555

Rauniyar, Navin; McClatchy, Daniel B; Yates, John R

2013-03-20

416

Quantitative analysis of estimated scattering coefficient and phase retardation for ovarian tissue characterization  

PubMed Central

In this report, optical scattering coefficient and phase retardation quantitatively estimated from polarization-sensitive OCT (PSOCT) were used for ovarian tissue characterization. A total of 33 ex vivo ovaries (normal: n = 26, malignant: n = 7) obtained from 18 patients were investigated. A specificity of 100% and a sensitivity of 86% were achieved by using estimated scattering coefficient alone; and a specificity of 100% and a sensitivity of 43% were obtained by using phase retardation alone. However, a superior specificity of 100% and sensitivity of 100% were achieved if these two parameters were used together for classifying normal and malignant ovaries. Quantitative measurement of collagen content obtained from Sirius red histology sections shows that it correlates with estimated scattering coefficient and phase retardation. Our initial results demonstrate that quantitative analysis of PSOCT could be a potentially valuable method for distinguishing normal from malignant ovarian tissues during minimally invasive surgery and help guide surgical intervention.

Yang, Yi; Wang, Tianheng; Wang, Xiaohong; Sanders, Melinda; Brewer, Molly; Zhu, Quing

2012-01-01

417

iTRAQ-based quantitative analysis of protein mixtures with large fold change and dynamic range.  

PubMed

Quantitation of changes in protein abundance is key to understanding the alterations that biological systems undergo and to discovering novel biomarkers. Currently, HPLC-MS/MS can be used to quantify changes in protein expression levels [Ong, S. E. and Mann, M., Nat. Chem. Biol. 2005, 1, 252-262]. Nevertheless, quantitative analysis of protein mixtures by HPLC-MS/MS is still hampered by the wide range of protein expression levels, the high dynamic range of protein concentrations and the lack of reliable quantitation algorithms [D'Ascenzo, M., et al. Brief. Funct. Genomic. Proteomic. 2008, 7, 127-135; Lin, W. T., et al., J. Proteome Res. 2006, 5, 2328-2338; Matthiesen, R., et al. J. Proteome Res. 2005, 4, 2338-2347; Yu, C. Y., et al. Nucleic Acids Res. 2007, 35, W707-W712]. In this context, we describe two different samples (4-protmix and 8-protmix) suitable for relative protein quantitation using iTRAQ. Using the 4-protmix, relative protein changes of up to 24-fold were measured. The 8-protmix allowed the quantitation of the relative protein changes in a mixture of proteins within the range of two orders of magnitude in concentration and ten-fold differences in relative abundance. We propose that the two samples are suited to test the iTRAQ quantitative proteomic workflow. We analyzed the iTRAQ samples with a LTQ Orbitrap using "higher energy collision-induced dissociation" fragmentation [Olsen, J. V., et al., Nat. Methods 2007, 4, 709-712] and quantified with Proteome Discoverer v.1.1 (Thermo Fisher Scientific). We believe that the presented protein mixtures will be useful to assess the performance of the iTRAQ-based quantitation proteomic strategy in any laboratory. PMID:20029838

Casado-Vela, Juan; Martínez-Esteso, María José; Rodriguez, Eva; Borrás, Eva; Elortza, Felix; Bru-Martínez, Roque

2010-01-01

418

The Trouble With Tailings: How Alteration Mineralogy can Hinder Quantitative Phase Analysis of Mineral Waste  

NASA Astrophysics Data System (ADS)

Quantitative phase analysis, using the Rietveld method and X-ray powder-diffraction data, has become a standard technique for analysis of mineral waste from mining operations. This method relies upon the availability of well defined crystal structures for all detectable mineral phases in a sample. An even more basic assumption, central to quantitative mineralogy, is that all significant mineral phases can be detected from X-ray diffraction data. This is not always the case, because X-ray amorphous and nanocrystalline mineral phases can develop within geological samples as a result of chemical weathering. The extent of mineral-water interaction to which mine tailings are exposed, during processing and storage, makes these materials particularly susceptible to weathering and alteration. We have used the Rietveld method and X-ray powder-diffraction data to quantify the uptake of atmospheric CO2 into secondary carbonate minerals at two operating mines: the Diavik Diamond Mine, Northwest Territories, Canada, and the Mount Keith Nickel Mine, Western Australia, Australia. At Diavik, nominally anhydrous minerals in kimberlitic mine tailings have been found to contain X-ray amorphous material and hydroxyl groups detectable by Raman spectroscopy. A series of weighed mixtures, prepared to simulate kimberlite mine tailings, has been used to assess the effects of X-ray amorphous material on quantitative phase analysis of Diavik tailings. At Mount Keith, hydrated sulphate minerals and halide minerals develop efflorescent crusts at the surface of the tailings storage facility. Hydrated sulphate minerals in these mine tailings commonly decompose to amorphous substances rather than dehydrating to produce minerals detectable from X-ray powder-diffraction patterns. Nanocrystalline and X-ray amorphous material in mine tailings can affect the accuracy of quantitative determinations of CO2 trapping and abundances of sulphur-bearing minerals associated with redox reactions. Here we assess the impact of amorphous material on quantitative X-ray diffraction results with particular reference to CO2 sequestration and suggest strategies for detection and analysis.

Wilson, S. A.; Mills, S. J.; Dipple, G. M.; Raudsepp, M.

2009-05-01

419

Quantitative fractography  

Microsoft Academic Search

In many disciplines, such as biology, botany, geology, materials science and medicine, quantitative image analysis is being used to an increasing extent. In materials science this technique makes it possible to relate the microsctructure to the mechanical properties. In this review we shall show that image analysis can be applied in a fractographic study to characterize quantitatively the morphology of

J. L. Chermant; M. Coster

1979-01-01

420

Bioanalytical LC separation techniques for quantitative analysis of free amino acids in human plasma.  

PubMed

The quantitative analysis of free amino acids in human plasma has become an important and essential analysis parameter in different areas of life sciences. Free amino acid concentrations in human plasma samples are generally determined by means of GC or LC after chemical derivatization followed by UV, fluorescent or MS detection of the amino acid derivatives. Derivatization of free amino acids is done either pre- or post-column, and the amino acid derivatives obtained posess improved chromatographic behavior, increased detection sensitivity and selectivity compared with non-derivatized free amino acids. This work gives an overview of different chemical derivatization methods applied and their liquid separation techniques in bioanalytical assays for quantitative free amino acid analysis in human plasma samples. Important plasma preparation procedures, pre- and post-column derivatization, and different LC separation techniques are presented. PMID:23414381

Meesters, Roland Jw

2013-02-01

421

Quantitative end qualitative analysis of the electrical activity of rectus abdominis muscle portions.  

PubMed

The purpose of this study was to investigate the electrical behavior pattern of the Rectus abdominis muscle by qualitative and quantitative analysis of the electromyographic signal obtained from its superior, medium and inferior portions during dynamic and static activities. Ten voluntaries (aged X = 17.8 years, SD = 1.6) athletic males were studied without history of muscle skeletal disfunction. For the quantitative analysis the RMS (Root Mean Square) values obtained in the electromyographic signal during the isometric exercises were normalized and expressed in maximum voluntary isometric contraction percentages. For the qualitative analysis of the dynamic activity the electromyographic signal was processed by full-wave rectification, linear envelope and normalization (amplitude and time), so that the resulting curve of the processed signal was submitted to descriptive graphic analysis. The results of the quantitative study show that there is not a statistically significant difference among the portions of the muscle. Qualitative analysis demonstrated two aspects: the presence of a common activation electric pattern in the portions of Rectus abdominis muscle and the absence of significant difference in the inclination angles in the electrical activity curve during the isotonic exercises. PMID:12964259

Negrão Filho, R de Faria; Bérzin, F; Souza, G da Cunha

422

A novel real-time PCR assay for quantitative analysis of methylated alleles (QAMA): analysis of the retinoblastoma locus  

Microsoft Academic Search

Altered methylation patterns have been found to play a role in developmental disorders, cancer and aging. Increasingly, changes in DNA methylation are used as molecular markers of disease. Therefore, there is a need for reliable and easy to use techniques to detect and measure DNA methylation in research and routine diagnostics. We have established a novel quantitative analysis of methylated

Michael Zeschnigk; Stefan Bohringer; Ann Price; Zerrin Onadim; Dietmar R. Lohmann

2004-01-01

423

HPTLC Hyphenated with FTIR: Principles, Instrumentation and Qualitative Analysis and Quantitation  

NASA Astrophysics Data System (ADS)

In recent years, much effort has been devoted to the coupling of high-performance thin-layer chromatography (HPTLC) with spectrometric methods because of the robustness and simplicity of HPTLC and the need for detection techniques that provide identification and determination of sample constituents. IR is one of the spectroscopic methods that have been coupled with HPTLC. IR spectroscopy has a high potential for the elucidation of molecular structures, and the characteristic absorption bands can be used for compound-specific detection. HPTLC-FTIR coupled method has been widely used in the modern laboratories for the qualitative and quantitative analysis. The potential of this method is demonstrated by its application in different fields of analysis such as drug analysis, forensic analysis, food analysis, environmental analysis, biological analysis, etc. The hyphenated HPTLC-FTIR technique will be developed in the future with the aim of taking full advantage of this method.

Cimpoiu, Claudia

424

Rapid and sensitive quantitative analysis of alkyl phosphates in urine after organophosphate poisoning.  

PubMed

Organophosphate compounds are widely used as pesticides. After ingestion by humans, organophosphates decompose into alkyl phosphates. Decomposition continues postmortem. We developed a rapid (< 3 h), quantitative, and sensitive analysis of the human organosphosphate metabolites O,O-dimethylphosphate (DMP), O,O-diethylphosphate (DEP), O,O-dimethylthiophosphate (DMTP), O,O-diethylthiophosphate (DETP), O,O-dimethyldithiophosphate (DMDTP), and O,O-diethyldithiophosphate (DEDTP). Urine is dried under azeotropic conditions with isopropanol and nitrogen. All metabolites are converted into their corresponding benzyl esters reacting with benzyl bromide and diazotoluene. The protocol prevents the isomerization of DMTP and DETP occurring when diazo compounds are used exclusively. The benzyl ester derivatives are purified on solid-phase extraction silica columns. The quantitative analysis is performed by gas chromatography-mass spectrometry. All metabolites can be identified by the parent molecular ions. Urine samples from eight cases of fatal suicidal poisoning dialkyl phosphates were quantitated. The limits of detection ranged from 3 to 6 ng/mL. Hence, this protocol is sufficiently sensitive to detect and quantitate organophosphate metabolites beyond cases of fatal poisoning, in the clinical setting, and even following average environmental exposure. PMID:15189674

Kupfermann, N; Schmoldt, A; Steinhart, H

425

Multidimensional analysis system for quantitative chemistry problems: Symbol, macro, micro, and process aspects  

NASA Astrophysics Data System (ADS)

There is a consensus regarding the fact that students encounter difficulties in understanding scientific concepts, such as the particulate nature of matter, the mole, and the interpretation of chemical symbols. Researchers and practitioners have been looking for teaching methods to improve students' understanding of quantitative chemistry and their ability to solve related problems. This study describes the Multidimensional Analysis System (MAS), an approach to constructing, classifying, and analyzing quantitative chemistry problems. MAS enables classification based on complexity and transformation levels of a quantitative problem. We define three transformation levels: symbol macro, symbol micro, and symbol process. Applying this framework to teaching and research, we investigated the relationships between MAS-classified chemistry problems and student achievement in solving these problems. The research population, 241 high school chemistry students, studied problem solving according to MAS for 9 weeks; the control group studied the same topic for the same duration in the traditional way. Student achievement was sorted by mathematics level and gender. We found that the success rate of the entire student population in solving these problems decreased as the problem difficulty increased. Experimental group students scored significantly higher than their control group peers. The improvement in student achievement was significantly dependent on the pretest score and the mathematics level, and independent of gender. Students who studied mathematics in the basic level benefited significantly more from MAS-based teaching than their peers, whose mathematics level was advanced. Based on the research findings, we recommend applying the multidimensional analysis approach while teaching quantitative problems in chemistry.

Dori, Yehudit J.; Hameiri, Mira

2003-03-01

426

Quantitative proteomic analysis of human lung tumor xenografts treated with the ectopic ATP synthase inhibitor citreoviridin.  

PubMed

ATP synthase is present on the plasma membrane of several types of cancer cells. Citreoviridin, an ATP synthase inhibitor, selectively suppresses the proliferation and growth of lung cancer without affecting normal cells. However, the global effects of targeting ectopic ATP synthase in vivo have not been well defined. In this study, we performed quantitative proteomic analysis using isobaric tags for relative and absolute quantitation (iTRAQ) and provided a comprehensive insight into the complicated regulation by citreoviridin in a lung cancer xenograft model. With high reproducibility of the quantitation, we obtained quantitative proteomic profiling with 2,659 proteins identified. Bioinformatics analysis of the 141 differentially expressed proteins selected by their relative abundance revealed that citreoviridin induces alterations in the expression of glucose metabolism-related enzymes in lung cancer. The up-regulation of enzymes involved in gluconeogenesis and storage of glucose indicated that citreoviridin may reduce the glycolytic intermediates for macromolecule synthesis and inhibit cell proliferation. Using comprehensive proteomics, the results identify metabolic aspects that help explain the antitumorigenic effect of citreoviridin in lung cancer, which may lead to a better understanding of the links between metabolism and tumorigenesis in cancer therapy. PMID:23990911

Wu, Yi-Hsuan; Hu, Chia-Wei; Chien, Chih-Wei; Chen, Yu-Ju; Huang, Hsuan-Cheng; Juan, Hsueh-Fen

2013-08-21

427

Quantitative Proteomic Analysis of Human Lung Tumor Xenografts Treated with the Ectopic ATP Synthase Inhibitor Citreoviridin  

PubMed Central

ATP synthase is present on the plasma membrane of several types of cancer cells. Citreoviridin, an ATP synthase inhibitor, selectively suppresses the proliferation and growth of lung cancer without affecting normal cells. However, the global effects of targeting ectopic ATP synthase in vivo have not been well defined. In this study, we performed quantitative proteomic analysis using isobaric tags for relative and absolute quantitation (iTRAQ) and provided a comprehensive insight into the complicated regulation by citreoviridin in a lung cancer xenograft model. With high reproducibility of the quantitation, we obtained quantitative proteomic profiling with 2,659 proteins identified. Bioinformatics analysis of the 141 differentially expressed proteins selected by their relative abundance revealed that citreoviridin induces alterations in the expression of glucose metabolism-related enzymes in lung cancer. The up-regulation of enzymes involved in gluconeogenesis and storage of glucose indicated that citreoviridin may reduce the glycolytic intermediates for macromolecule synthesis and inhibit cell proliferation. Using comprehensive proteomics, the results identify metabolic aspects that help explain the antitumorigenic effect of citreoviridin in lung cancer, which may lead to a better understanding of the links between metabolism and tumorigenesis in cancer therapy.

Wu, Yi-Hsuan; Hu, Chia-Wei; Chien, Chih-Wei; Chen, Yu-Ju; Huang, Hsuan-Cheng; Juan, Hsueh-Fen

2013-01-01

428

Quantitative analysis of biological tissues using Fourier transform-second-harmonic generation imaging  

NASA Astrophysics Data System (ADS)

We demonstrate the use of Fourier transform-second-harmonic generation (FT-SHG) imaging of collagen fibers as a means of performing quantitative analysis of obtained images of selected spatial regions in porcine trachea, ear, and cornea. Two quantitative markers, preferred orientation and maximum spatial frequency are proposed for differentiating structural information between various spatial regions of interest in the specimens. The ear shows consistent maximum spatial frequency and orientation as also observed in its real-space image. However, there are observable changes in the orientation and minimum feature size of fibers in the trachea indicating a more random organization. Finally, the analysis is applied to a 3D image stack of the cornea. It is shown that the standard deviation of the orientation is sensitive to the randomness in fiber orientation. Regions with variations in the maximum spatial frequency, but with relatively constant orientation, suggest that maximum spatial frequency is useful as an independent quantitative marker. We emphasize that FT-SHG is a simple, yet powerful, tool for extracting information from images that is not obvious in real space. This technique can be used as a quantitative biomarker to assess the structure of collagen fibers that may change due to damage from disease or physical injury.

Ambekar Ramachandra Rao, Raghu; Mehta, Monal R.; Toussaint, Kimani C., Jr.

2010-02-01

429

QARIP: a web server for quantitative proteomic analysis of regulated intramembrane proteolysis  

PubMed Central

Regulated intramembrane proteolysis (RIP) is a critical mechanism for intercellular communication and regulates the function of membrane proteins through sequential proteolysis. RIP typically starts with ectodomain shedding of membrane proteins by extracellular membrane-bound proteases followed by intramembrane proteolysis of the resulting membrane-tethered fragment. However, for the majority of RIP proteases the corresponding substrates and thus, their functions, remain unknown. Proteome-wide identification of RIP protease substrates is possible by mass spectrometry-based quantitative comparison of RIP substrates or their cleavage products between different biological states. However, this requires quantification of peptides from only the ectodomain or cytoplasmic domain. Current analysis software does not allow matching peptides to either domain. Here we present the QARIP (Quantitative Analysis of Regulated Intramembrane Proteolysis) web server which matches identified peptides to the protein transmembrane topology. QARIP allows determination of quantitative ratios separately for the topological domains (cytoplasmic, ectodomain) of a given protein and is thus a powerful tool for quality control, improvement of quantitative ratios and identification of novel substrates in proteomic RIP datasets. To our knowledge, the QARIP web server is the first tool directly addressing the phenomenon of RIP. The web server is available at http://webclu.bio.wzw.tum.de/qarip/. This website is free and open to all users and there is no login requirement.

Ivankov, Dmitry N.; Bogatyreva, Natalya S.; Honigschmid, Peter; Dislich, Bastian; Hogl, Sebastian; Kuhn, Peer-Hendrik; Frishman, Dmitrij; Lichtenthaler, Stefan F.

2013-01-01

430

Efficient Antifouling Surface for Quantitative Surface Plasmon Resonance Based Biosensor Analysis  

PubMed Central

Non-specific binding to biosensor surfaces is a major obstacle to quantitative analysis of selective retention of analytes at immobilized target molecules. Although a range of chemical antifouling monolayers has been developed to address this problem, many macromolecular interactions still remain refractive to analysis due to the prevalent high degree of non-specific binding. In this manuscript we explore the dynamic process of the formation of self-assembled monolayers and optimize physical and chemical properties thus reducing considerably non-specific binding while maintaining the integrity of the immobilized biomolecules. As a result, analysis of specific binding of analytes to immobilized target molecules is significantly facilitated.

Nogues, Claude; Leh, Herve; Lautru, Joseph; Delelis, Olivier; Buckle, Malcolm

2012-01-01

431

Visualisation and Quantitative Analysis of the Rodent Malaria Liver Stage by Real Time Imaging  

PubMed Central

The quantitative analysis of Plasmodium development in the liver in laboratory animals in cultured cells is hampered by low parasite infection rates and the complicated methods required to monitor intracellular development. As a consequence, this important phase of the parasite's life cycle has been poorly studied compared to blood stages, for example in screening anti-malarial drugs. Here we report the use of a transgenic P. berghei parasite, PbGFP-Luccon, expressing the bioluminescent reporter protein luciferase to visualize and quantify parasite development in liver cells both in culture and in live mice using real-time luminescence imaging. The reporter-parasite based quantification in cultured hepatocytes by real-time imaging or using a microplate reader correlates very well with established quantitative RT-PCR methods. For the first time the liver stage of Plasmodium is visualized in whole bodies of live mice and we were able to discriminate as few as 1–5 infected hepatocytes per liver in mice using 2D-imaging and to identify individual infected hepatocytes by 3D-imaging. The analysis of liver infections by whole body imaging shows a good correlation with quantitative RT-PCR analysis of extracted livers. The luminescence-based analysis of the effects of various drugs on in vitro hepatocyte infection shows that this method can effectively be used for in vitro screening of compounds targeting Plasmodium liver stages. Furthermore, by analysing the effect of primaquine and tafenoquine in vivo we demonstrate the applicability of real time imaging to assess parasite drug sensitivity in the liver. The simplicity and speed of quantitative analysis of liver-stage development by real-time imaging compared to the PCR methodologies, as well as the possibility to analyse liver development in live mice without surgery, opens up new possibilities for research on Plasmodium liver infections and for validating the effect of drugs and vaccines on the liver stage of Plasmodium.

Douradinha, Bruno G.; Ramesar, Jai; Fonager, Jannik; van Gemert, Geert-Jan; Luty, Adrian J. F.; Hermsen, Cornelus C.; Sauerwein, Robert W.; Baptista, Fernanda G.; Mota, Maria M.; Waters, Andrew P.; Que, Ivo; Lowik, Clemens W. G. M.; Khan, Shahid M.; Janse, Chris J.; Franke-Fayard, Blandine M. D.

2009-01-01

432

Quantitative analysis of dipyridamole-thallium images for the detection of coronary artery disease  

SciTech Connect

To determine if the detection of coronary artery disease by dipyridamole-thallium imaging is improved by quantitative versus qualitative analysis, and combining quantitative variables, 80 patients with chest pain (53 with and 27 without coronary artery disease) who underwent cardiac catheterization were studied. Segmental thallium initial uptake, linear clearance, monoexponential clearance and redistribution were measured from early, intermediate and delayed images acquired in three projections. Normal values were determined from 13 other clinically normal subjects. When five segments per view were used for quantitative analysis, sensitivity and specificity were 87 and 63%, respectively, for uptake, 77 and 67% for linear clearance, 60 and 60% for monoexponential clearance and 62 and 56% for redistribution. Of the four variables, uptake and linear clearance were the most sensitive (p less than 0.01) and specificity did not differ significantly. Using three segments per view, the specificity of uptake increased to 78% without a significant change in sensitivity (85%). With this approach, sensitivity and specificity did not differ from those of qualitative analysis (85 and 78%, respectively). Stepwise logistic regression analysis demonstrated that the best quantitative thallium correlate of the presence of coronary artery disease was a combination variable of ''either abnormal uptake or abnormal linear clearance, or both.'' Using five segments per view, the model's specificity (85%) was greater than that of uptake alone, with similar sensitivity (92%). Using three segments per view, the model's specificity (93%) was greater than that of uptake alone and of qualitative analysis (p less than 0.05), with similar sensitivity (85%).

Ruddy, T.D.; Dighero, H.R.; Newell, J.B.; Pohost, G.M.; Strauss, H.W.; Okada, R.D.; Boucher, C.A.

1987-07-01

433

Quantitative analysis of the nanopore translocation dynamics of simple structured polynucleotides.  

PubMed

Nanopore translocation experiments are increasingly applied to probe the secondary structures of RNA and DNA molecules. Here, we report two vital steps toward establishing nanopore translocation as a tool for the systematic and quantitative analysis of polynucleotide folding: 1), Using ?-hemolysin pores and a diverse set of different DNA hairpins, we demonstrate that backward nanopore force spectroscopy is particularly well suited for quantitative analysis. In contrast to forward translocation from the vestibule side of the pore, backward translocation times do not appear to be significantly affected by pore-DNA interactions. 2), We develop and verify experimentally a versatile mesoscopic theoretical framework for the quantitative analysis of translocation experiments with structured polynucleotides. The underlying model is based on sequence-dependent free energy landscapes constructed using the known thermodynamic parameters for polynucleotide basepairing. This approach limits the adjustable parameters to a small set of sequence-independent parameters. After parameter calibration, the theoretical model predicts the translocation dynamics of new sequences. These predictions can be leveraged to generate a baseline expectation even for more complicated structures where the assumptions underlying the one-dimensional free energy landscape may no longer be satisfied. Taken together, backward translocation through ?-hemolysin pores combined with mesoscopic theoretical modeling is a promising approach for label-free single-molecule analysis of DNA and RNA folding. PMID:22225801

Schink, Severin; Renner, Stephan; Alim, Karen; Arnaut, Vera; Simmel, Friedrich C; Gerland, Ulrich

2012-01-03

434

Quantitative Analysis of the Nanopore Translocation Dynamics of Simple Structured Polynucleotides  

PubMed Central

Nanopore translocation experiments are increasingly applied to probe the secondary structures of RNA and DNA molecules. Here, we report two vital steps toward establishing nanopore translocation as a tool for the systematic and quantitative analysis of polynucleotide folding: 1), Using ?-hemolysin pores and a diverse set of different DNA hairpins, we demonstrate that backward nanopore force spectroscopy is particularly well suited for quantitative analysis. In contrast to forward translocation from the vestibule side of the pore, backward translocation times do not appear to be significantly affected by pore-DNA interactions. 2), We develop and verify experimentally a versatile mesoscopic theoretical framework for the quantitative analysis of translocation experiments with structured polynucleotides. The underlying model is based on sequence-dependent free energy landscapes constructed using the known thermodynamic parameters for polynucleotide basepairing. This approach limits the adjustable parameters to a small set of sequence-independent parameters. After parameter calibration, the theoretical model predicts the translocation dynamics of new sequences. These predictions can be leveraged to generate a baseline expectation even for more complicated structures where the assumptions underlying the one-dimensional free energy landscape may no longer be satisfied. Taken together, backward translocation through ?-hemolysin pores combined with mesoscopic theoretical modeling is a promising approach for label-free single-molecule analysis of DNA and RNA folding.

Schink, Severin; Renner, Stephan; Alim, Karen; Arnaut, Vera; Simmel, Friedrich C.; Gerland, Ulrich

2012-01-01

435

Pneumatically assisted electrospray-ion mobility spectrometry for quantitative analysis of intact proteins.  

PubMed

In this work, quantitative analysis of intact proteins using ion mobility spectrometry (IMS) is introduced. For this purpose a pneumatically assisted electrospray ionization source with a new design was constructed. Liquid and nebulizer gas flow rates were optimized to achieve the highest response. The pneumatically assisted electrospray-IMS was used for quantitative analysis of insulin, bovine serum albumin (BSA) and human serum albumin (HSA). The analysis of proteins demonstrated that sensitivity of the pneumatically assisted electrospray-IMS is two to three times higher than that of conventional electrospray ionization (ESI) coupled to IMS. The linear dynamic ranges for insulin, BSA and HSA were found to be 1-75, 5-100 and 2-100 ?g mL(-1) with detection limits of 0.3, 1 and 0.6 ?g mL(-1), respectively. The relative standard deviations (RSD) for five replicate measurements of insulin, BSA, and HSA at 25 ?g mL(-1) were recorded as 3, 4 and 1.5%, respectively. The proposed method can be considered as an alternative way for quantitative protein analysis. PMID:22967517

Arabzadeh, N; Khayamian, T

2012-05-17

436

Quantitative Analysis for Monitoring Formulation of Lubricating Oil Using Terahertz Time-Domain Transmission Spectroscopy  

NASA Astrophysics Data System (ADS)

The quantitative analysis of zinc isopropyl-isooctyl-dithiophosphate (T204) mixed with lube base oil from Korea with viscosity index 70 (T204-Korea70) is presented by using terahertz time-domain spectroscopy (THz-TDS). Compared with the middle-infrared spectra of zinc n-butyl-isooctyl-dithiophosphate (T202) and T204, THz spectra of T202 and T204 show the weak broad absorption bands. Then, the absorption coefficients of the T204-Korea70 system follow Beer's law at the concentration from 0.124 to 4.024%. The experimental absorption spectra of T204-Korea70 agree with the calculated ones based on the standard absorption coefficients of T204 and Korea70. The quantitative analysis enables a strategy to monitor the formulation of lubricating oil in real time.

Tian, Lu; Zhao, Kun; Zhou, Qing-Li; Shi, Yu-Lei; Zhang, Cun-Lin

2012-04-01

437

[Quantitative analysis of ovalbumin by thin-layer isoelectric focusing (author's transl)].  

PubMed

A new method for quantitation of ovalbumin by thin layer isoelectric focusing in polyacrylamide gel is described. This technique separates ovalbumin from avian-magnum homogenates or egg white and allows the quantitative determination of each ovalbumin fraction. Considering the very small amount (7 mul) of sample needed for an analysis, the sensitivity and the reproducibility of the proposed method are good. The application of this technique to quail egg white ovalbumin analysis leads to the characterization of four fractions A3, A2, A1 and A0 containing, respectively, 0, 1, 2 and 3 atoms of phosphorus per mole and with isoelectric points that range from 4.95 (A3) to 4.65 (A0). PMID:999880

Laugier, C J; Seigne, M; Brard, E V

1976-11-26

438

Colorimetric assays for quantitative analysis and screening of epoxide hydrolase activity.  

PubMed

Focusing on directed evolution to tailor enzymes as usable biocatalysts for fine chemistry, we have studied in detail several colorimetric assays for quantitative analysis of epoxide hydrolase (EH) activity. In particular, two assays have been optimized to characterize variants issued from the directed evolution of the EH from Aspergillus niger. Assays described in this paper are sufficiently reliable for quantitative screening of EH activity in microtiter plates and are low cost alternatives to GC or MS analysis. Moreover, they are usable for various epoxides and not restricted to a type of substrate, such as those amenable to assay by UV absorbancy. They can be used to assay EH activity on any epoxide and to directly assay enantioselectivity when both (R) and (S) substrates are available. The advantages and drawbacks of these two methods to assay EH activity of a large number of natural samples are summarized. PMID:16328991

Cedrone, F; Bhatnagar, T; Baratti, Jacques C

2005-12-01

439

Quantitative analysis on the urban flood mitigation effect by the extensive green roof system.  

PubMed

Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. PMID:23892044

Lee, J Y; Moon, H J; Kim, T I; Kim, H W; Han, M Y

2013-07-25

440

Artificial neural network for on-site quantitative analysis of soils using laser induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

Nowadays, due to environmental concerns, fast on-site quantitative analyses of soils are required. Laser induced breakdown spectroscopy is a serious candidate to address this challenge and is especially well suited for multi-elemental analysis of heavy metals. However, saturation and matrix effects prevent from a simple treatment of the LIBS data, namely through a regular calibration curve. This paper details the limits of this approach and consequently emphasizes the advantage of using artificial neural networks well suited for non-linear and multi-variate calibration. This advanced method of data analysis is evaluated in the case of real soil samples and on-site LIBS measurements. The selection of the LIBS data as input data of the network is particularly detailed and finally, resulting errors of prediction lower than 20% for aluminum, calcium, copper and iron demonstrate the good efficiency of the artificial neural networks for on-site quantitative LIBS of soils.

El Haddad, J.; Villot-Kadri, M.; Ismaël, A.; Gallou, G.; Michel, K.; Bruyère, D.; Laperche, V.; Canioni, L.; Bousquet, B.

2013-01-01

441

Pore3D: A software library for quantitative analysis of porous media  

NASA Astrophysics Data System (ADS)

In recent years great interest has been posed in imaging techniques like X-ray computed microtomography which in a nondestructive way produce three-dimensional (3D) images of the internal structure of, e.g. porous media. A major challenge lies in the quantitative analysis of the resulting images that allows a more comprehensive and objective characterization of the sample under investigation. A software able to handle and process large 3D image datasets with common hardware is therefore necessary in order to extract morphological and textural information directly from the images. In the present paper the Pore3D software library developed by the SYRMEP research group of the Elettra Synchrotron Light Laboratory in Trieste (Italy) is presented. The library consists of several state-of-the-art functions and procedures for performing filtering, segmentation and quantitative analysis of 3D images. The current status of the project and some applications are here reported.

Brun, Francesco; Mancini, Lucia; Kasae, Parnian; Favretto, Stefano; Dreossi, Diego; Tromba, Giuliana

2010-04-01

442

Key Parameters Affecting Quantitative Analysis of STEM-EDS Spectrum Images  

SciTech Connect

In this article, we use simulated and experimental data to explore how three operator-controllable parameters - (1) signal level, (2) detector resolution, and (3) number of factors chosen for analysis - affect quantitative analyses of scanning transmission electron microscopy-energy dispersive X-ray spectroscopy spectrum images processed by principal component analysis (PCA). We find that improvements in both signal level and detector resolution improve the precision of quantitative analyses, but that signal level is the most important. We also find that if the rank of the PCA solution is not chosen properly, it may be possible to improperly fit the underlying data and degrade the accuracy of results. Additionally, precision is degraded in the case when too many factors are included in the model.

Brewer, Luke [Sandia National Laboratories (SNL); Parish, Chad M [ORNL

2010-06-01

443

Quantitative analysis of lithium in Al-Li alloys by ionization energy loss spectroscopy  

Microsoft Academic Search

A quantitative analysis of lithium in Al-Li alloys has been carried out by ionization energy loss spectroscopy. It has been found that the power law I = A E gives the best fit to the background immediately preceding the Li-K edge, and that the optimum value of the spectrometer acceptance semi-angle ? is about 2 mrad. The Al:Li ratio on

Helen M. Chan; David B. Williams

1985-01-01

444

Analysis and quantitation of biotinylated apoB-containinglipoproteinswith streptavidin-Cy3  

Microsoft Academic Search

Non denaturing gradient gel electrophoresis (GGE) is commonly used to analyze the size distribution of lipoprotein particles. Its relatively low sensitivity and linear dynamic range limit use of GGE to quantify protein content of lipoproteins. We demonstrate a new high sensitivity method for analysis and quantitation of biotinylated apoli- poprotein B (apoB)-containing lipoproteins using a fluores- cent streptavidin-Cy3 conjugate and

Kaspar Berneis; Michael La Belle; Patricia J. Blanche; Ronald M. Krauss

2002-01-01

445

Quantitative analysis of cytokinins in plants by liquid chromatography–single-quadrupole mass spectrometry  

Microsoft Academic Search

A sensitive method for the quantitative analysis of all natural isoprenoid cytokinins in plant material by electrospray single-quadrupole mass spectrometry is presented. A baseline chromatographic separation of 20 non-derivatised naturally occurring cytokinins has been developed. Precise analyses of O-glucoside and ribonucleotide fractions were also performed by the high-performance liquid chromatography–mass spectrometry (HPLC–MS) but run separately from the basic cytokinin metabolites.

Ond?ej Novák; Petr Tarkowski; Danuše Tarkowská; Karel Doležal; René Lenobel; Miroslav Strnad

2003-01-01

446

Strengthening CMMI Maturity Levels with a Quantitative Approach to Root-Cause Analysis  

Microsoft Academic Search

This paper discusses and analyses the opportunity to approach a typical TQM qualitative technique such as Root-Cause Analysis (RCA), expressed with the well-known Ishikawa (or Fishbone) diagrams, in a quantitative manner. Adding a control measure at the end of each 'cause bone' can help decision-makers in their determination of corrective\\/improvement actions to take in terms of how much to introduce

Luigi Buglione

2008-01-01

447

Direct quantitative analysis of peptides using matrix assisted laser desorption ionization  

Microsoft Academic Search

The protocol and various matrices were examined for quantification of biomolecules in both the low ca. 1200 amu and mid mass 6000–12000 amu ranges using an internal standard. Comparative studies of different matrices of MALDI quantitative analysis showed that the best accuracy and standard curve linearity were obtained for two matrices: (a) 2,5-dihydroxybenzoic acid (DHB) combined with a comatrix of

Arkady I. Gusev; William R. Wilkinson; Andrew Proctor; David M. Hercules

1996-01-01

448

Quantitative analysis of siRNA-mediated GFP silencing in transgenic pine cells  

Microsoft Academic Search

A quantitative analysis approach of siRNA-mediated green fluorescence protein gene (gfp) silencing was established in this investigation. This approach is based on both the application of transgenic cells using GFP as a visual marker and siRNA-mediated gfp silencing in Virginia pine (Pinus virginiana Mill.). We used m-gfp5-ER as a reporter gene to examine design rules for efficient gene silencing in

Wei Tang; Douglas Weidner; Ronald J. Newton

2005-01-01

449

Application of LC–MS for quantitative analysis and metabolite identification of therapeutic oligonucleotides  

Microsoft Academic Search

Therapeutic oligonucleotides (OGNs) have been studied extensively in the recent years as novel agents designed to selectively and specifically inhibit target gene expression in cell culture, in animal disease models and in human. This review summarizes applications of liquid chromatography coupled with mass spectrometry or tandem mass spectrometry (LC–MS or LC–MS\\/MS) for quantitative analysis of therapeutic OGNs and characterization of

Zhongping John Lin; Wenkui Li; Guowei Dai

2007-01-01

450

Esterolytic Antibodies as Mechanistic and Structural Models of Hydrolases—A Quantitative Analysis  

Microsoft Academic Search

Understanding enzymes quantitatively and mimicking their remarkable catalytic efficiency is a paramount challenge. Here, we applied esterolytic antibodies (the D-Abs) to dissect and quantify individual elements of enzymatic catalysis such as transition state (TS) stabilization, nucleophilic reactivity and conformational changes. Kinetic and mutagenic analysis of the D-Abs were combined with existing structural evidence to show that catalysis by the D-Abs

Ariel B. Lindner; Se Ho Kim; Dan G. Schindler; Zelig Eshhar; Dan S. Tawfik

2002-01-01