A new method of arranging phytosociological tables by species-releve groups (blocks) on the basis of the density of rows and columns (relative species frequency and relative species number) is presented. Each block fu...
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A new method of arranging phytosociological tables by species-releve groups (blocks) on the basis of the density of rows and columns (relative species frequency and relative species number) is presented. Each block fulfils a given minimum criterion regarding its density. With a density threshold of e.g. 50 %, blocks are formed with only those species that are present in at least 50 % of the block's releves, while at the same time the block's releves comprise at least 50 % of the block's species. The procedure starts with the complete table and iteratively masks species and releves with the smallest densities. This is performed step by step with species and releves and continues until the given density threshold for all species and releves is exceeded. Without any further parameters other than the minimum density, species-releve groups of gradually decreasing size are formed. Data processing is performed with a computer program (ESPRESSO). The main application of the method is found in an effective pre-sorting of releve data. The blocks formed can be arranged in the final table as desired.
The method of regularization for estimating unit hydrographs is expanded to allow the inclusion of prior information about the unit hydrograph shape. This may give smooth estimates without any loss in volume. The meth...
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The method of regularization for estimating unit hydrographs is expanded to allow the inclusion of prior information about the unit hydrograph shape. This may give smooth estimates without any loss in volume. The method is illustrated with prior information from a regression on catchment characteristics and with catchment lag deter- mined from the data. A computer program to implement the method is given together with a sample calculation.
Graphical, computational, interactive, and simulation capabilities of computers can be successfully employed in the teaching of elementary probability, either as classroom demonstrations or as exploratory exercises in...
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Graphical, computational, interactive, and simulation capabilities of computers can be successfully employed in the teaching of elementary probability, either as classroom demonstrations or as exploratory exercises in a computer laboratory. In this first paper of a contemplated series, two programs for EGA-equipped IBM-PC compatible machines are included with indications of their pedagogical uses. Concepts illustrated include the law of large numbers, the frequentist definition of a probability, the Poisson distribution and process, and intuitive approaches to independence and randomness. (Commands for rough equivalents to the programs using Minitab are shown in theAppendix.)
Two BASIC computer programs using logit transformation for the analysis of S-shaped curves are presented. The first program estimates the median effective dose (ED50) Of drugs. A maximum likelihood method similar to F...
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Two BASIC computer programs using logit transformation for the analysis of S-shaped curves are presented. The first program estimates the median effective dose (ED50) Of drugs. A maximum likelihood method similar to Finney's algorithm of probit analysis is applied. The second fits S-shaped curves to empirical data which cannot be transformed easily to proportions. Logit transformation proves to be a simple and accurate alternative to probit transformation when computing memory is limited or calculation speed is critical.
In clinical management and research of movement disorders exact knowledge about the extent of motor impairment is essential. This paper presents a computer program which allows for an objective measurement of manual m...
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In clinical management and research of movement disorders exact knowledge about the extent of motor impairment is essential. This paper presents a computer program which allows for an objective measurement of manual movement disability. The program was developed for standard hardware and can easily be used in a variety of clinical and research environments. The program runs on MS-DOS computers and uses a Microsoft computer mouse as the only input device. The temporal resolution is 100 Hz, the spatial resolution 400 dots per inch. The user may choose between standard test sets or he may design sets according to his individual needs from a pool of available protocols which includes tracking tasks, ballistic tasks, complex sequential tasks, and finger tapping. All tasks are implemented in a similar way in order to keep the test environment as consistent as possible for the patient. The patient must usually carry out movements which correspond to the movements of a target symbol on the computer screen. This entails the manipulation of a follower symbol, also visible on the computer screen, via the computer mouse. The program itself and the theoretical background of the protocols are described in the paper. Additionally, preliminary results from pilot experiments are presented.
The Atmospheric Oxidation program (AOP) is a computer program constant for the atmospheric, gas-phase reaction between photochemically produced hydroxyl radicals (OH) and organic chemicals. It also estimates the rate ...
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The Atmospheric Oxidation program (AOP) is a computer program constant for the atmospheric, gas-phase reaction between photochemically produced hydroxyl radicals (OH) and organic chemicals. It also estimates the rate constant for the gas-phase reaction between ozone and olefinic/acetylenic compounds. AOP, which uses estimation methods developed by Atkinson and co-workers, estimates more accurate rate constants than the PCFAP (Fate of Atmospheric Pollutants) program that was part of the U.S. EPA's Graphical Exposure Modeling System (GEMS). Due to its superior predictive ability, the EPA is currently using AOP to evaluate the atmospheric fate of compounds defined under Sections 4, 5 and 6 of the Toxic Substances Control Act (TSCA).
Geotechnical engineers need to study soil properties by conducting a number of field and laboratory tests. Processing geotechnical engineering laboratory test data is laborious and takes considerable time when doing i...
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Geotechnical engineers need to study soil properties by conducting a number of field and laboratory tests. Processing geotechnical engineering laboratory test data is laborious and takes considerable time when doing it manually. The present paper explains the need of a computer package to process geotechnical engineering laboratory data and the details of a computer program which is being developed for this use. The different stages of the program are explained with the laboratory tests considered with the help of flow charts. The use of the program is illustrated with an example. Possible improvements to the program are proposed.
The analysis of receptor binding experiments involving saturation or displacement curves may represent a problem when data are obtained from a number of experimental groups characterized by different tissues or differ...
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The analysis of receptor binding experiments involving saturation or displacement curves may represent a problem when data are obtained from a number of experimental groups characterized by different tissues or different treatments. The conceptual difficulty of comparing such binding parameters and the complexity in graphically representing many curves is often overcome using tables and statistical tests for uncorrelated parameters. These, however, might be misleading. In fact, computing parameters using a nonlinear least squares (NLLS) technique may yield a significant covariance or correlation in the parameter *** the present paper we suggest a practical method for comparing curves from different experimental groups using the LIGAND program and present the program MacELLIPSE that permits the graphical representation of the binding results together with the correlation existing between the estimated parameters.
A specific and new method for measuring Interleukin-4 and Interferon-gamma, based on the estimation of IgG1 and IgG2a isotypes secretion from B cells is described. An antagonizing effect of Interferon-gamma in the pro...
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A specific and new method for measuring Interleukin-4 and Interferon-gamma, based on the estimation of IgG1 and IgG2a isotypes secretion from B cells is described. An antagonizing effect of Interferon-gamma in the production of IgG1 induced by Interleukin-4 was neutralized by using antibody to Interferon-gamma. Similarly, the interference of Interleukin-4 in the Interferon-gamma mediated enhancement of IgG2a production was blocked by anti-Interleukin-4 antibody. The high concentrations of Interleukin-4 and Interferon gamma inhibited the secretion of IgG1 and IgG2a respectively. Therefore, in the assay described, the samples containing the cytokines were so diluted that their activity fell into the non-inhibitory zone. A computer program has also been developed for determining the concentrations of lymphokines.
Random mutagenesis is a powerful tool in protein structure-function analyses. One approach to random mutagenesis is the de novo synthesis of polypeptide-encoding oligodeoxy-nucleotides using doped nucleoside phosphora...
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Random mutagenesis is a powerful tool in protein structure-function analyses. One approach to random mutagenesis is the de novo synthesis of polypeptide-encoding oligodeoxy-nucleotides using doped nucleoside phosphoramidites. A Turbo PASCAL program, RAMHA, is described for modeling such mutagenesis. Upon entering the target sequence and the desired level of nucleotide contamination, RAMHA performs a Monte Carlo simulation of the mutagenesis, compiling statistics on the similarity of resultant mutant polypeptides to the wild-type sequence, the frequency of premature open-reading frame terminations, and other relevant outcomes. Simulated mutagenesis of two DNA targets has led to the development of two different strategies to avoid the random introduction of stop codons within mutagenized gene segments.
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