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Standard Analyses (standard + analysis)
Selected AbstractsHyperreal transients in transfinite RLC networksINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 6 2001A. H. Zemanian Abstract Up to the present time, there have been no transient analyses of RLC transfinite networks. Standard analyses of transfinite networks have been restricted to purely resistive ones. In this paper, it is shown how non-standard analysis can be used to examine the transient behaviour of transfinite networks having lumped resistors, inductors, and capacitors. To do so, the time line is expanded into the hyperreal time line, and the transients obtained take on hyperreal values. It is also shown how the diffusion of signals on artificial RC cables and the propagation of waves on artificial RLC transmission lines can ,pass through infinity' and penetrate transfinite extensions of those cables and lines. Less precisely but more suggestively, we can say that diffusions and waves can reach,with appreciable values,nodes that are transfinitely far away from their starting points, but that it will take infinitely long times in order to get there. Copyright © 2001 John Wiley & Sons, Ltd. [source] The effect of cutting and fish-orientation systems on the deheading yield of carpINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2008Andrzej Dowgiallo Summary Applied research into carp-deheading yield indicated that the V-cut with two circular knives averaged 77.9%; the V-cut with one cup-type knife , 75.6%, and the straight cut at a 79° angle to the fish backbone , 77.4%. The yield averages for deheaded and gutted carp were 63.6%, 62.4% and 62.9%, respectively. Standard analysis of variance demonstrated that there were no statistically significant differences between the mean yields of these three deheading systems. Furthermore, the potential influence of the fish-orientation system in close connection with the cutting systems on the deheading yield was analysed. This indicated that, with the same yields, the straight-cutting system simplifies the precise orientation of the fish in relation to the cutting knives. [source] Characterizing multiple independent behavioral correlates of cell firing in freely moving animalsHIPPOCAMPUS, Issue 2 2005Neil Burgess Abstract The heterogeneous sampling of behavioral states by freely moving animals hinders our ability to relate neuronal firing rates to behavioral variables by introducing dependencies between them. We specifically consider the animal's location and orientation, although our analyses may generalize to other behavioral variables, such as speed of movement. A maximum-likelihood approach is presented for producing estimates of the separate histograms relating firing rate to multiple independent causes. Examples show that the method can be used to avoid the artifactual behavioral correlates of place and head direction-cell firing produced by standard analyses; to characterize the independent influences of both location and orientation in a third cell type (Cacucci et al., 2004); and to demonstrate the location-independence of the directional firing of head-direction cells. © 2004 Wiley-Liss, Inc. [source] Putting the colours into chromogenic in situ hybridization (CISH)THE JOURNAL OF PATHOLOGY, Issue 1 2006J Shipley Abstract Recurrent genomic alterations are the hallmarks of particular cancers. Application of molecular cytogenetic technologies to tumour material in order to detect these alterations has become important for molecular diagnostics and research. A dual-colour chromogenic in situ hybridization (dc-CISH) method described recently in the Journal of Pathology has the advantage of visualizing two probes simultaneously with the ability to discern morphological features. In addition, the bright field microscopy required is readily accessible to many laboratories. The approach has been validated by comparison of results with standard analyses for HER-2 amplification status in formalin-fixed, paraffin-embedded breast cancers and is applicable to the analysis of other clinically relevant genomic aberrations as well as of use in research investigations. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Multiple Imputation Methods for Treatment Noncompliance and Nonresponse in Randomized Clinical TrialsBIOMETRICS, Issue 1 2009L. Taylor Summary Randomized clinical trials are a powerful tool for investigating causal treatment effects, but in human trials there are oftentimes problems of noncompliance which standard analyses, such as the intention-to-treat or as-treated analysis, either ignore or incorporate in such a way that the resulting estimand is no longer a causal effect. One alternative to these analyses is the complier average causal effect (CACE) which estimates the average causal treatment effect among a subpopulation that would comply under any treatment assigned. We focus on the setting of a randomized clinical trial with crossover treatment noncompliance (e.g., control subjects could receive the intervention and intervention subjects could receive the control) and outcome nonresponse. In this article, we develop estimators for the CACE using multiple imputation methods, which have been successfully applied to a wide variety of missing data problems, but have not yet been applied to the potential outcomes setting of causal inference. Using simulated data we investigate the finite sample properties of these estimators as well as of competing procedures in a simple setting. Finally we illustrate our methods using a real randomized encouragement design study on the effectiveness of the influenza vaccine. [source] Megalencephalic leukoencephalopathy with subcortical cysts: an update and extended mutation analysis of MLC1,HUMAN MUTATION, Issue 6 2006P. K. Ilja Boor Abstract Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an autosomal recessive cerebral white matter disorder in children. This disease is histopathologically characterized by myelin splitting and intramyelinic vacuole formation. MLC is caused by mutations in the gene MLC1, which encodes a novel protein, MLC1. Since the first report, 50 mutations in this gene have been found. Mutations occur throughout the entire coding region and include all different types: 11 splice-site mutations; one nonsense mutation; 24 missense mutations; and 14 deletions and insertions. Until now, six polymorphisms within the coding sequence of MLC1 had been reported. In about 20% of the patients with a typical clinical and MRI picture, no mutations in the MLC1 gene are found. Several of the families, in which no mutations are found, also do not show linkage with the MLC1 locus, which suggests a second gene involved in MLC. The absence of mutations may also be the consequence of performing standard mutation analysis that can miss heterozygous deletions, mutations in the promoter, 3, and 5, untranslated regions (UTRs), and intron mutations, which may influence the amino acid composition of the end product. In this work we describe 13 novel mutations, including those found with extended mutation analysis on MLC patients. This study shows that extended mutation analysis is a valuable tool to identify at least some of the missing mutations. Therefore, we suggest extended mutation analysis for the MLC1 gene, if no mutations are found during standard analysis. Hum Mutat 27(6), 505,512, 2006. © 2006 Wiley-Liss, Inc. [source] Bayesian statistics in medical research: an intuitive alternative to conventional data analysisJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2000AStat, Lyle C. Gurrin BSc (Hons) Summary Statistical analysis of both experimental and observational data is central to medical research. Unfortunately, the process of conventional statistical analysis is poorly understood by many medical scientists. This is due, in part, to the counter-intuitive nature of the basic tools of traditional (frequency-based) statistical inference. For example, the proper definition of a conventional 95% confidence interval is quite confusing. It is based upon the imaginary results of a series of hypothetical repetitions of the data generation process and subsequent analysis. Not surprisingly, this formal definition is often ignored and a 95% confidence interval is widely taken to represent a range of values that is associated with a 95% probability of containing the true value of the parameter being estimated. Working within the traditional framework of frequency-based statistics, this interpretation is fundamentally incorrect. It is perfectly valid, however, if one works within the framework of Bayesian statistics and assumes a ,prior distribution' that is uniform on the scale of the main outcome variable. This reflects a limited equivalence between conventional and Bayesian statistics that can be used to facilitate a simple Bayesian interpretation based on the results of a standard analysis. Such inferences provide direct and understandable answers to many important types of question in medical research. For example, they can be used to assist decision making based upon studies with unavoidably low statistical power, where non-significant results are all too often, and wrongly, interpreted as implying ,no effect'. They can also be used to overcome the confusion that can result when statistically significant effects are too small to be clinically relevant. This paper describes the theoretical basis of the Bayesian-based approach and illustrates its application with a practical example that investigates the prevalence of major cardiac defects in a cohort of children born using the assisted reproduction technique known as ICSI (intracytoplasmic sperm injection). [source] Proximity magnetoresistance in Ag70Fe30 and Ag74Fe26 cosputtered granular filmsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 12 2004P. Allia Abstract Granular films of composition Ag70Fe30 and Ag74Fe26 were prepared by dc plasma sputtering deposition in Ar atmosphere on Si substrates. Magnetization and magnetoresistance were measured between 2 K and 270 K. Both films exhibit a negative magnetoresistance (MR). The MR vs. reduced magnetisation curves are characterised by a box-like behavior, as already observed in magnetic systems with competing interactions. A standard analysis indicates that in both systems individual Fe nanoparticles are magnetically correlated over large distances. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||