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ECG Variable Cine:: computer program for presentation of temporal changes in ECG variables over different number of ECG leads

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computer METHODS AND programS IN BIOMEDICINE 2000年第2期63卷 147-155页

作者： Viik, J Vänttinen, H Malmivuo, J Tampere Univ Technol Ragnar Granit Inst FIN-33101 Tampere Finland

The analysis of exercise electrocardiogram (ECG) is based on the alteration of the measured variables in the detection of corollary artery disease (CAD). In its existing form the analysis of the exercise ECG is laborious and requires much time. The temporal analysis of the ECG variable and the comparison between different phases of the exercise test is difficult and time consuming, especially the simultaneous examination of the variables over several leads. in this article we present a computer program, ECG Variable Cine, for the visualization of the temporal changes of values of exercise ECG variables over the selected ECG lead system. The program includes the stationary 3-D presentation for the variables' alteration simultaneously in all selected leads over the time of exercise test. In addition, the program determines two parameters;the average value of the variable over the selected leads at every sample moment, and the chronotropic index, a parameter that indicates heart rate response to exercise. According to the results the average value of ST-segment deviation at the end of the exercise over the leads and chronotropic index are clinically more competent than the maximum value of ST-segment depression in the detection of CAD. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.

关键词： ECG exercise rest computer program

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Design of maximum density aggregate grading

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CONSTRUCTION AND BUILDING MATERIALS 2002年第8期16卷 495-508页

作者： Abdel-Jawad, YA Abdullah, WS Jordan Univ Sci & Technol Dept Civil Engn Fac Engn Irbid Jordan

An aggregate grading that yields maximum solid density and maximum particle interlock is highly desirable for both bound mixture, and Mixtures such as those used in base S, such as asphalt concrete and plain and reinforced concrete, and for unbound courses. Maximum particle interlock leads to high strength. Whereas minimum voids in a certain material composition is conducive to high strength and low compression. Aggregate grading may be obtained, for instance, from the ASTM, which is based on experience or may be designed according to Lees' method. In the present work five different types of aggregates were used, each with a variety of chosen grading. It was found that Lees' method produced the lowest porosity of all types of aggregated as well as for the various employed gradings. Lees' rational method of aggregate grading, however, is a very lengthy and time-consuming procedure. Therefore, programming of Lees' method is an essential step to make such an excellent method available to practicing engineers. A program named 'RATMIX' was developed and has incorporated 58 design graphs of the Lees' method. RATMIX is a comprehensive program for Lees' rational method;it conducts interpolation for intermediate points within the design graphs as well as between graphs of different properties. (C) 2002 Elsevier Science Ltd. All rights reserved.

关键词： aggregate grading maximum density rational method ASTM Fuller's method Lees' method computer program

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CHIMERA: A software tool for reaction rate calculations and kinetics and thermodynamics analysis

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JOURNAL OF COMPUTATIONAL CHEMISTRY 2002年第14期23卷 1375-1389页

作者： Novoselov, KP Shirabaikin, DB Umanskii, SY Vladimirov, AS Minushev, AK Korkin, AA Motorola Inc Semicond Prod Sector Mesa AZ 85202 USA JSC Soft Tec Moscow 117218 Russia Russian Acad Sci NN Semenov Chem Phys Inst Moscow 117977 Russia

This article presents and overviews the CHIMERA program package, which provides a user-friendly graphical interface between quantum chemistry and chemical kinetics programs. CHIMERA facilitates calculations of rate constants for gas-phase reactions using transition state and Rice-Ramsperger-Kassel-Marcus theories. The program includes computational modules for simulation of gas-phase kinetics using simplified reactor models and for computation of chemical equilibria. The review includes a description of the theory implemented in the code, the program description, the general strategy of calculations using CHIMERA, and illustrative examples of the program application. (C) 2002 Wiley Periodicals, Inc.

关键词： computer program chemical kinetics rate constants reactor modeling

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Characterization and modeling of illite crystal particles and growth mechanisms in a zoned hydrothermal deposit, Lake City, Colorado

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AMERICAN MINERALOGIST 2002年第11-12期87卷 1546-1556页

作者： Bove, DJ Eberl, DD McCarthy, DK Meeker, GP US Geol Survey Denver CO 80225 USA US Geol Survey Boulder CO 80303 USA Texaco EPTD Houston TX 77042 USA

Mean thickness measurements and crystal-thickness distributions (CTDs) of illite particles vary systematically with changes in hydrothermal alteration type, fracture density, and attendant mineralization in a large acid-sulfate/Mo-porphyry hydrothermal system at Red Mountain, near Lake City, Colorado. The hydrothermal illites characterize an extensive zone of quartz-sericite-pyrite alteration beneath two deeply rooted bodies of magmatic-related, quartz-alunite altered rock. Nineteen illites from a 3000 ft vertical drill hole were analyzed by XRD using the PVP-10 intercalation method and the computer program MudMaster (Bertaut-Warren-Averbach technique). Mean crystallite thicknesses, as determined from 001 reflections, range from 5-7 nanometers (nm) at depths from 0-1700 ft, then sharply increase to 10-16 nm at depths between 1800-2100 ft, and decrease again to 4-5 nm below this level. The interval of largest particle thickness correlates strongly with the zone of most intense quartz-sericite-pyrite alteration (QSP) and attendant high-density stockwork fracturing, and with the highest concentrations of Mo within the drill core. CTD shapes for the illite particles fall into two main categories: asymptotic and lognormal. The shapes of the CTDs are dependent on conditions of illite formation. The asymptotic CTDs correspond to a nucleation and growth mechanism, whereas surface-controlled growth was the dominant mechanism for the lognormal CTDs. Lognormal CTDs coincide with major through-going fractures or stockwork zones, whereas asymptotic CTDs are present in wallrock distal to these intense fracture zones. The increase in illite particle size and the associated zone of intense QSP alteration and stockwork veining was related by proximity to the dacitic magma(s), which supplied both reactants and heat to the hydrothermal system. However, no changes in illite polytype, which in other studies reflect temperature transitions, were observed within this interval.

关键词： .crystallite PVP shapes computer program thicknesses MEAN THICKNESS illites hydrothermal alteration Lake City Qsp hydrothermal system Growth mechanisms CTDs illite particles Red Mountain quartz-sericite-pyrite quartz-alunite MudMaster nm at depths particle thickness drill core

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Kinetic investigation on the dehydration of coprecipitated mixed oxide powders

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JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY 2002年第3期68卷 787-801页

作者： Bujoreanu, VM Frangu, L Segal, E Dunarea de Jos Univ Galati Dept Met & Mat Sci Galati 6200 Romania Dunarea de Jos Univ Galati Dept Automat & Elect Galati 6200 Romania Univ Bucharest Fac Chem Dept Phys Chem Bucharest 70346 Romania

The authors present an original kinetic model and a computer program in order to determine the mass of various types of water from the oxide powders obtained through co-precipitation, using thermogravimetric data. The model is based on kinetic equations in the framework of the reaction order desorption of the water loss. The program minimizes the mean square deviation between the experimental TG curve and the approximation curve;it allows visualizing the experimental and the approximated TG curves for the overall process, as well as the approximated TG and DTG curves for the individual processes. The influence of the aging time and temperature on the mass of various types of water to be found in the co-precipitated manganese ferrite powder was investigated based on this original kinetic model and the suitable computer program. Some correlations between the water release and microstructure changes of the powder during aging in mother solution are presented.

关键词： computer program co-precipitation dehydration kinetic model kinetic parameters manganese ferrite powder microstructure changes TG curve deconvolution water types

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Internet programs for drawing moth pheromone analogs and searching literature database

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JOURNAL OF CHEMICAL ECOLOGY 2002年第4期28卷 807-817页

作者： Byers, JA Swedish Univ Agr Sci Dept Crop Sci SE-23053 Alnarp Sweden

An Internet web page is described for organizing and analyzing information about lepidopteran sex pheromone components. Hypertext markup language(HTML) with JavaScript program code is used to draw moth pheromone analogs by combining GIF bitmap images for viewing by web browsers such as Netscape or Microsoft Internet Explorer. Straight-chain hydrocarbons of 5-22 carbons with epoxides or unsaturated positions of E or Z geometrical configuration with several alternative functional groups can be drawn by simply checking menu bars or checkboxes representing chain length, E/Z unsaturation points, epoxide position and chirality, and optional functional groups. The functional group can be an aldehyde, alcohol, or ester of formate, acetate, propionate, or butyrate. The program is capable of drawing several million structures and naming them [e.g., (E,E)-8,10-dodecadien-1-ol and abbreviated as E8E10-12:OH]. A Java applet program run from the same page searches for the presently drawn structure in an internal database compiled from the Pherolist, and if the component is found, provides a textarea display of the families and species using the component. Links are automatically specified for drawn components if found in the Pherolist web site (maintained by H. Arn). Windowed links can also be made to two other JavaScript programs that allow searches of a web site database with over 5900 research citations on lepidopteran semiochemicals and a calculator of vapor pressures of some moth sex pheromone analogs at a specified temperature. Various evolutionary and biosynthetic aspects are discussed in regard to the diversity of moth sex pheromone components.

关键词： Lepidoptera moth pheromone components epoxides aldehydes alcohols acetate esters Internet JavaScript computer program Java applet database vapor pressures

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Semiautomatic sequence-specific assignment of proteins based on the tertiary structure -: The program st2nmr

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JOURNAL OF COMPUTATIONAL CHEMISTRY 2002年第3期23卷 335-340页

作者： Pristovsek, P Rüterjans, H Jerala, R Natl Inst Chem Ljubljana 1000 Slovenia Univ Frankfurt Inst Biophys Chem D-60439 Frankfurt Germany

The sequence-specific assignment of resonances is still the most time-consuming procedure that is necessary as the first step in high-resolution NMR studies of proteins. In many cases a reliable three-dimensional (3D) structure of the protein is available, for example, from X-ray spectroscopy or homology modeling. Here we introduce the st2nmr program that uses the 3D structure and Nuclear Overhauser Effect spectroscopy (NOESY) peak list(s) to evaluate and optimize trial sequence-specific assignments of spin systems derived from correlation spectra to residues of the protein. A distance-dependent target function that scores trial assignments based on the presence of expected NOESY crosspeaks is optimized in a Monte Carlo fashion. The performance of the program st2nmr is tested on real NMR data of an alpha-helical (cytochrome c) and beta-sheet (lipocalin) protein using homology models and/or X-ray structures;it succeeded in completely reproducing the correct sequence-specific assignments in most cases using 2D and/or N-15/C-13 Nuclear Overhauser Effect (NOE) data. Additionally to amino acid residues the program can also handle ligands that are bound to the protein, such as heme, and can be used as a complementary tool to fully automated assignment procedures.(C) 2002 John Wiley Sons, Inc.

关键词： automatic NMR assignment sequential assignment protein structure computer program homology modeling

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The β-barrel finder (BBF) program, allowing identification of outer membrane β-barrel proteins encoded within prokaryotic genomes

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PROTEIN SCIENCE 2002年第9期11卷 2196-2207页

作者： Zhai, YF Saier, MH Univ Calif San Diego Dept Biol La Jolla CA 92093 USA

Many outer membrane proteins (OMPs) in Gram-negative bacteria possess known beta-barrel three-dimensional (313) structures. These proteins, including channel-forming transmembrane porins, are diverse in sequence but exhibit common structural features. We here report computational analyses of six outer membrane proteins of known 3D structures with respect to (1) secondary structure, (2) hydropathy, and (3) amphipathicity. Using these characteristics, as well as the presence of an N-terminal targeting sequence, a program was developed allowing prediction of integral membrane beta-barrel proteins encoded within any completely sequenced prokaryotic genome. This program, termed the beta-barrel finder (BBF) program, was used to analyze the proteins encoded within the Escherichia coli genome. Out of 4290 sequences examined, 118 (2.8%) were retrieved. Of these, almost all known outer membrane proteins with established beta-barrel structures as well as many probable outer membrane proteins were identified. This program should be useful for predicting the occurrence of outer membrane proteins in bacteria with completely sequenced genomes.

关键词： computer program bacteria outer membranes beta-barrel porins genome sequences hydropathy amphipathicity protein structure

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In vitro phototoxicity testing:: Development and validation of a new concentration response analysis software and biostatistical analyses related to the use of various prediction models

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ATLA-ALTERNATIVES TO LABORATORY ANIMALS 2002年第4期30卷 415-432页

作者： Peters, B Holzhütter, HG Humboldt Univ Charite Inst Biochem Fak Med D-10117 Berlin Germany

As demonstrated in several validation studies, the dermal phototoxic potential of chemicals in humans can be effectively assessed by in vitro methods. The core of these methods is to monitor dose-response curves of a chemical in the absence and presence of light, to quantify the difference between these two curves by appropriate measures (either the photo-irritancy factor [PIF], or the mean photo effect [MPE]), and to use these measures as predictors of in vivo phototoxicity. We present new concentration-response analysis software for in vitro phototoxicity testing, which runs on current personal computers, and takes into account all the limitations identified when using a former program. We also demonstrate the validity and robustness of this new software by applying it retrospectively to all data available from two phases of the EU/COLIPA validation trial for the 3T3 neutral red update in vitro phototoxicity test. Some frequently raised questions pertaining to the use of prediction models in phototoxicity testing are addressed, including: the necessity of using prediction models based on a cut-off;whether it is justifiable to use sharp prediction cut-off values;whether there is a biostatistical justification for the highest concentration of the test chemical;and whether repeated testing of a chemical is required.

关键词： bootstrapping computer program dose-response curve phototoxicity statistics

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Software for temporal gait data analysis

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computer METHODS AND programS IN BIOMEDICINE 2002年第3期67卷 225-229页

作者： Kyriazis, V Rigas, C Univ Ioannina Sch Med Med Phys Lab GR-45110 Ioannina Greece

This study presents a computer program, developed to support a low-cost, portable telemetry system that has been designed to assess footfall timing. This software frees: the user from data processing and allows concentration on data analysis. The new technique has been applied with accuracy and reliability to the analysis of the gait of orthopedic patients, athletes, mountaineers, etc. The subroutines developed for data acquisition, storage and analysis are explained in detail, and an example is presented. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

关键词： computer program processed data raw data telemetry system temporal gait analysis

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