The DISCON Algorithm,an Accurate and Robust Alternative to an Eigenvalue Solution for Extracting Experimental Distances from NOESY Data

The DISCON algorithm is a novel, computationally direct, iterative solution for cross-relaxation rates that can be applied to a single NOESY data set without prior knowledge of the applicable motional regime or a structural model. Tests with simulated NOESY data demonstrate that it is less subject to error propagation from incorrect autopeak values than an eigenvalue solution. The resulting cross rates are fully corrected for secondary NOE contributions. The algorithm has been incorporated into a software suite that provides distance estimates and their experimental precision from raw NOESY data. Missing values in the data matrix are approximated as class averages of existing data rather than calculated values based on a starting conformational model; thus, more accurate initial distance estimates for modeling can be derived without a starting model bias. The accuracy of the program is demonstrated using NOESY data for a rigid steroid, Its application for conformational analysis is illustrated with a flexible prostaglandin analog.     

一种实用的多功能的函数拟合程序

研制了函数拟合程序.本程序主要特点在于可键盘或联机输入实验数据.利用计算机图示功能,手动、或自动拟合,以寻求最佳。本系统能打印出拟合后各参数的最佳值。并能在数字绘图仪上分别画出实验数据和理论曲线或光谱分解后的各分立子谱带。     

A Pragmatic Ensemble Strategy for Missing Values Imputation in Health Records

Pristine and trustworthy data are required for efficient computer modelling for medical decision-making, yet data in medical care is frequently missing. As a result, missing values may occur not just in training data but also in testing data that might contain a single undiagnosed episode or a participant. This study evaluates different imputation and regression procedures identified based on regressor performance and computational expense to fix the issues of missing values in both training and testing datasets. In the context of healthcare, several procedures are introduced for dealing with missing values. However, there is still a discussion concerning which imputation strategies are better in specific cases. This research proposes an ensemble imputation model that is educated to use a combination of simple mean imputation, k-nearest neighbour imputation, and iterative imputation methods, and then leverages them in a manner where the ideal imputation strategy is opted among them based on attribute correlations on missing value features. We introduce a unique Ensemble Strategy for Missing Value to analyse healthcare data with considerable missing values to identify unbiased and accurate prediction statistical modelling. The performance metrics have been generated using the eXtreme gradient boosting regressor, random forest regressor, and support vector regressor. The current study uses real-world healthcare data to conduct experiments and simulations of data with varying feature-wise missing frequencies indicating that the proposed technique surpasses standard missing value imputation approaches as well as the approach of dropping records holding missing values in terms of accuracy.     

Inverting chaos: Extracting system parameters from experimental data

Given a set of experimental or numerical chaotic data and a set of model differential equations with several parameters, is it possible to determine the numerical values for these parameters using a least-squares approach, and thereby to test the model against the data? We explore this question (a) with simulated data from model equations for the Rossler, Lorenz, and pendulum attractors, and (b) with experimental data produced by a physical chaotic pendulum. For the systems considered in this paper, the least-squares approach provides values of model parameters that agree well with values obtained in other ways, even in the presence of modest amounts of added noise. For experimental data, the "fitted" and experimental attractors are found to have the same correlation dimension and the same positive Lyapunov exponent. (c) 1996 American Institute of Physics.     

Fertilizer nitrogen isotope signatures

There has been considerable recent interest in the potential application of nitrogen isotope analysis in discriminating between organically and conventionally grown crops. A prerequisite of this approach is that there is a difference in the nitrogen isotope compositions of the fertilizers used in organic and conventional agriculture. We report new measurements of delta15N values for synthetic nitrogen fertilizers and present a compilation of the new data with existing literature nitrogen isotope data. Nitrogen isotope values for fertilizers that may be permitted in organic cultivation systems are also reported (manures, composts, bloodmeal, bonemeal, hoof and horn, fishmeal and seaweed based fertilizers). The delta15N values of the synthetic fertilizers in the compiled dataset fall within a narrow range close to 0 per thousand with 80% of samples lying between-2 and 2 per thousand and 98.5% of the data having delta15N values of less than 4 per thousand (mean=0.2 per thousand n=153). The fertilizers that may be permitted in organic systems have a higher mean delta15N value of 8.5 per thousand and exhibit a broader range in delta15N values from 0.6 to 36.7 per thousand (n=83). The possible application of the nitrogen isotope approach in discriminating between organically and conventionally grown crops is discussed in light of the fertilizer data presented here and with regard to other factors that are also important in determining crop nitrogen isotope values.     

The 1983 atomic mass evaluation: (II). Nuclear-reaction and separation energies

The present table gives values and their estimated precision for the separation energies and reaction energies representing together twelve carefully selected combinations of nuclides with ΔA < 5. These data are derived from a least-squares evaluation of all available experimental data. A method is indicated in which many more reaction energy values can be derived from the present data.     

Phyllosilicates: A Mössbauer evaluation

Based on the Mössbauer data of minerals extracted from theMineral: Data Handbook, a consistent set of best values for the isomeric shifts and the quadrupole splittings for ferrous and ferric ions in the cis and trans sites of phyllosilicate is given. The parameters, in particular the quadrupole splitting values, can be used in an analogous way for the identification of minerals as the Hanawalt and Fink methods of powder x-ray diffraction data where each mineral is identified by a set of unique Mössbauer data.     

Noise Analysis of Duplicated Data on Microarrays Using Mixture Distribution Modeling

We propose a technique for estimating gene expression values for duplicated data on cDNA microarrays. In the scatter plots, the distribution is constructed from a mixture of normal two-dimensional distributions, which represent fluctuations in gene expression values due to noise. An expectation-maximization (EM) algorithm is used for estimating the modeling parameters. The probability that duplicated data is shifted by noise is calculated using Bayesian estimation. Six data sets of rice cDNA microarray assays were used to test the proposed technique. Genes in the data sets were subjected to clustering based on probability of true value. Clustering successfully identified candidate genes regulated by circadian rhythms in rice.     

Investigation of the boundary value problem corresponding to a generalized Skyrme lagrangian

A detailed numerical analysis of the boundary value problem resulting from the most general Skyrme type lagrangian containing up to quartic terms in field gradients is presented. The additional parameters in the lagrangian can be related to pion-pion scattering lengths. It is found that solutions to the boundary value problem does not exist for all values of the parameters and in particular, for the values predicted from pion-pion scattering data. Physical quantities of the nucleon are calculated for the highest possible values of the parameters admitting a solution and are compared with the corresponding values for the Skyrme model and experimental values.     

On the Blow Up and Condensation of Supercritical Solutions of the Nordheim Equation for Bosons

In this paper we prove that the solutions of the isotropic, spatially homogeneous Nordheim equation for bosons with bounded initial data blow up in finite time in the L ^∞ norm if the values of the energy and particle density are in the range of values where the corresponding equilibria contain a Dirac mass. We also prove that, in the weak solutions, whose initial data are measures with values of particle and energy densities satisfying the previous condition, a Dirac measure at the origin forms in finite time.     

The pressure and temperature derivatives of the elastic moduli of lithium hydride

The pressure and temperature derivatives of the elastic moduli of single crystal LiH have been determined at room temperature, by the ultrasonic pulse echo method. From the pressure data, the mode Grüneisen parameters as well as the low and high temperature limiting values of the Grüneisen constant were computed; the latter were only slightly different. An equation of state has been constructed for LiH, and found to be in agreement with the experimental data. Based on a non-central force model, the values of the elastic moduli and their pressure derivatives have been calculated theoretically, and the latter values compared with the experimental data.     

A lumped mucosal wave model of the vocal folds revisited: recent extensions and oscillation hysteresis

This paper examines an updated version of a lumped mucosal wave model of the vocal fold oscillation during phonation. Threshold values of the subglottal pressure and the mean (DC) glottal airflow for the oscillation onset are determined. Depending on the nonlinear characteristics of the model, an oscillation hysteresis phenomenon may occur, with different values for the oscillation onset and offset threshold. The threshold values depend on the oscillation frequency, but the occurrence of the hysteresis is independent of it. The results are tested against pressure data collected from a mechanical replica of the vocal folds, and oral airflow data collected from speakers producing intervocalic /h/. In the human speech data, observed differences between voice onset and offset may be attributed to variations in voice pitch, with a very small or inexistent hysteresis phenomenon.     

The NUBASE2016 evaluation of nuclear properties

This paper presents the NUBASE2016 evaluation that contains the recommended values for nuclear and decay properties of 3437 nuclides in their ground and excited isomeric(T_(1/2)≥100 ns) states.All nuclides for which any experimental information is known were considered.NUBASE2016 covers all data published by October 2016 in primary(journal articles) and secondary(mainly laboratory reports and conference proceedings) references,together with the corresponding bibliographical information.During the development of NUBASE2016,the data available in the "Evaluated Nuclear Structure Data File"(ENSDF) database were consulted and critically assessed for their validity and completeness.Furthermore,a large amount of new data and some older experimental results that were missing from ENSDF were compiled,evaluated and included in NUBASE2016.The atomic mass values were taken from the "Atomic Mass Evaluation"(AME2016,second and third parts of the present issue).In cases where no experimental data were available for a particular nuclide,trends in the behavior of specific properties in neighboring nuclides(TNN) were examined.This approach allowed to estimate values for a range of properties that are labeled in NUBASE2016 as "non-experimental"(flagged "#").Evaluation procedures and policies used during the development of this database are presented,together with a detailed table of recommended values and their uncertainties.     

Missing Value Imputation Method for Multiclass Matrix Data Based on Closed Itemset

Handling missing values in matrix data is an important step in data analysis. To date, many methods to estimate missing values based on data pattern similarity have been proposed. Most previously proposed methods perform missing value imputation based on data trends over the entire feature space. However, individual missing values are likely to show similarity to data patterns in local feature space. In addition, most existing methods focus on single class data, while multiclass analysis is frequently required in various fields. Missing value imputation for multiclass data must consider the characteristics of each class. In this paper, we propose two methods based on closed itemsets, CIimpute and ICIimpute, to achieve missing value imputation using local feature space for multiclass matrix data. CIimpute estimates missing values using closed itemsets extracted from each class. ICIimpute is an improved method of CIimpute in which an attribute reduction process is introduced. Experimental results demonstrate that attribute reduction considerably reduces computational time and improves imputation accuracy. Furthermore, it is shown that, compared to existing methods, ICIimpute provides superior imputation accuracy but requires more computational time.     

Recovery of spectral data using weighted canonical correlation regression

The weighted canonical correlation regression technique is employed for reconstruction of reflectance spectra of surface colors from the related XYZ tristimulus values of samples. Flexible input data based on applying certain weights to reflectance and colorimetric values of Munsell color chips has been implemented for each particular sample which belongs to Munsell or GretagMacbeth Colorchecker DC color samples. In fact, the colorimetric and spectrophotometric data of Munsell chips are selected as fundamental bases and the color difference values between the target and samples in Munsell dataset are chosen as a criterion for determination of weighting factors. The performance of the suggested method is evaluated in spectral reflectance reconstruction. The results show considerable improvements in terms of root mean square error (RMS) and goodness-of-fit coefficient (GFC) between the actual and reconstructed reflectance curves as well as CIELAB color difference values under illuminants A and TL84 for CIE1964 standard observer.     

Determination of rovibronic term values of a diatomic molecule from experimental data on the wavenumbers of spectral lines

It has been shown that, if experimental data are available on the lines of the rovibronic spectrum of a diatomic molecule that pairwise couple three or more vibronic states, then there is a relation between the wavenumbers measured for the lines and the absolute values of all corresponding rovibronic term values. A method is proposed for determining the optimal set of rovibronic term values with error estimations by varying the desired values of the rovibronic term values so as to minimize the weighted standard deviation of the wavenumbers that are calculated according to the Rydberg-Ritz combination principle from the wavenumbers measured for a sufficiently large number of rovibronic spectral lines of various systems of bands. It is substantial that this method does not require any assumptions on the molecular structure. The new method is applied to determine the rovibronic term values of 12 singlet electronic states of the isotopomer ¹¹B¹H of the boron hydride molecule, which have already been studied experimentally, with the use of all available experimental data for 15 systems of bands, which are obtained in 10 works. Thus, the energy spectrum of the diatomic molecule has been determined from the experimental data on the wavenumbers of rovibronic spectral lines without any assumption on its structure.     

Baseline Methods for Bayesian Inference in Gumbel Distribution

Usual estimation methods for the parameters of extreme value distributions only employ a small part of the observation values. When block maxima values are considered, many data are discarded, and therefore a lot of information is wasted. We develop a model to seize the whole data available in an extreme value framework. The key is to take advantage of the existing relation between the baseline parameters and the parameters of the block maxima distribution. We propose two methods to perform Bayesian estimation. Baseline distribution method (BDM) consists in computing estimations for the baseline parameters with all the data, and then making a transformation to compute estimations for the block maxima parameters. Improved baseline method (IBDM) is a refinement of the initial idea, with the aim of assigning more importance to the block maxima data than to the baseline values, performed by applying BDM to develop an improved prior distribution. We compare empirically these new methods with the Standard Bayesian analysis with non-informative prior, considering three baseline distributions that lead to a Gumbel extreme distribution, namely Gumbel, Exponential and Normal, by a broad simulation study.     

Experimental Results on Ultrahigh-Energy Cosmic Rays and Asymptotic Behavior of the Total Cross Section for Nucleon–Nucleon Interaction

Results obtained by studying the energy dependence of the total cross section for nucleon–nucleon interaction are presented. The analytic parametrization proposed within axiomatic quantum field theory describes quantitatively a unified set of experimental data on proton–proton and antiproton–proton scattering. At collision energies above 86 GeV, the parameter values fitted to subsets of all available data and accelerator data alone were found to deviate from the respective asymptotic values. This indicates that the Froissart–Martin limit for the total cross section has not yet been reached in the case of these subsets. An approximation of the total nucleon–nucleon cross section measured in cosmic rays leads for some parameters to fitted values that, within 1.0 to 1.3 standard deviations, agree with the respective asymptotic values. This resultmay be viewed as an indication of the beginning of the asymptotic functional behavior of the total nucleon–nucleon cross section measured in cosmic rays of ultrahigh energy O(100 TeV). This is confirmed within the color glass condensate approach.     

Dielectric susceptibility of a deuterated KDP crystal from experiment on Raman scattering and in the cluster approximation

The temperature dependence of the static dielectric susceptibility obtained from the experiment on Raman scattering in a deuterated KDP (DKDP) crystal has been described using the cluster approximation in terms of the microscopic mean-field theory. The optimum values obtained for parameters of the cluster approximation are in good agreement with experimental data over a wide temperature range. These values are found to be comparable to the estimates previously obtained in describing experimental data on the DKDP crystal.     

Cumulative Clearness Index Frequency Distributions on the Territory of the Russian Federation

Cumulative distributions of clearness index values are constructed for the territory of Russia based on ground observation results and NASA POWER data. The obtained distributions lie close to each other, which means that the NASA POWER data can be used in solar power installations simulation at temperate and high latitudes. Approximation of the obtained distributions is carried out. The values of equation coefficients for the cumulative clearness index distributions constructed for a wide range of climatic conditions are determined. Equations proposed for a tropical climate are used in the calculations, so they can be regarded as universal ones.