130 research outputs found
Voter attitudes to inter-party transfers in Northern Ireland: a median-difference analysis of inter-party transfers in the 1982 and 1998 Assembly elections
The impact of the 1998 peace agreement in Northern Ireland on electoral behaviour is analysed in this article by plotting median differences in inter-party transfers under the PR by Single Transferable Vote system used in 1998 and in 1982. There is clear evidence that moderate and militant nationalists have followed the lead of their party elites and have transferred lower preference votes to each other at higher levels and more consistently in 1998 than in 1982. Patterns of change within unionism are more complex.
While there were some signs of a slightly increased willingness from pro-Agreement unionists to transfer to moderate nationalists and a fall in the percentage of transfers to anti-Agreement unionists, there was still considerable consistency of support between the unionist parties despite the split over the peace agreement
Voter attitudes to inter-party transfers in Northern Ireland: a median-difference analysis of inter-party transfers in the 1982 and 1988 Assembly elections
The impact of the 1998 peace agreement in Northern Ireland on electoral behaviour is analysed in this article by plotting median differences in inter-party transfers under
the PR by Single Transferable Vote system used in 1998 and in 1982. There is clear evidence that moderate and militant nationalists have followed the lead of their party elites and have transferred lower preference votes to each other at higher levels and more consistently in 1998 than in 1982. Patterns of change within unionism are more complex. While there were some signs of a slightly increased willingness from pro-Agreement unionists to transfer to moderate nationalists and a fall in the percentage of transfers to anti-Agreement unionists, there was still considerable consistency of support between the unionist parties despite the split over the peace agreement
Silencing and recombination in yeast ribosomal DNA
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2008.Includes bibliographical references (p. 129-132).A bioinformatic and laboratory investigation into S. cerevisiae's system for the maintenance and homogenization of rDNA. Eliminating mutations and heterogeneity in rDNA repeats is necessary evolutionarily, but harmful to individual organisms--and has been linked to aging-related pathology. We present a forensic investigation of this process using a new whole-genome shotgun dataset, and interpret the results in light of experimental results showing the dynamics of rDNA silencing and recombination in laboratory strains.by Michael J.T. O'Kelly.Ph.D
Normal modes in damped systems
A general review of normal mode theory as applied to the vibration of linear damped lumped parameter bilateral systems is presented. It is shown that systems possessing classical damping may always be solved by the method developed by Rayleigh. However, for more general type non-classical damping the method proposed by F. A. Foss must be used, The main differences between classical and non-classical normal modes are noted. A non-classically damped system which does not possess a mode type solution is solved by La place Transform techniques.
The effect of damping on the natural frequencies of a linear system is discussed. It is shown that in classically damped systems increasing the damping decreases the natural frequencies of the system, With non-classical damping some of the natural frequencies of the damped system may be greater than the corresponding natural frequencies of the undamped system. From the perturbation analysis, used in determining the effect of damping on the natural frequencies of the system, the concept of equivalent classical damping for non-classically damped systems is derived.
Experimental techniques needed to determine the mode shapes, natural frequencies, mass spring and damping matrices of classically damped systems are presented. By the use of the concept of equivalent classical damping an estimate of the damping matrix in non-classical systems may be obtained. Experimental results supporting the theory are presented
General theory of vibration of damped linear dynamic systems
The usual treatment of linearly damped lumped parameter systems assumes that the system equations may be transformed to a symmetrical set of equations. This assumption is justified in passive systems. However, in many problems of interest to aeronautical and electrical engineers the system equations cannot be transformed to a symmetric set of equations. One case in point is the analysis of an aircraft wing under flutter conditions. That non-symmetric systems are physically realizable will be understood when one remembers that it is possible to build any non-symmetric system using an active analog computer. It is the purpose of this report to give a comprehensive analysis of lumped parameter linearly damped second order vibrating systems having symmetric or non-symmetric matrices
Guidelines for pre-operative cardiac risk assessment and perioperative cardiac management in non-cardiac surgery : the Task Force for Preoperative Cardiac Risk Assessment and Perioperative Cardiac Management in Non-cardiac Surgery of the European Society of Cardiology (ESC) and endorsed by the European Society of Anaesthesiology (ESA)
Non-cardiac surgery; Pre-operative cardiac risk assessment; Pre-operative cardiac testing; Pre-operative coronary artery revascularization; Perioperative cardiac management; Renal disease; Pulmonary disease; Neurological disease; Anaesthesiology; Post-operative cardiac surveillanc
Sensitivity analysis for clinical trials with missing continuous outcome data using controlled multiple imputation: a practical guide
Missing data due to loss to follow‐up or intercurrent events are unintended, but unfortunately inevitable in clinical trials. Since the true values of missing data are never known, it is necessary to assess the impact of untestable and unavoidable assumptions about any unobserved data in sensitivity analysis. This tutorial provides an overview of controlled multiple imputation (MI) techniques and a practical guide to their use for sensitivity analysis of trials with missing continuous outcome data. These include δ ‐ and reference‐based MI procedures. In δ ‐based imputation, an offset term, δ , is typically added to the expected value of the missing data to assess the impact of unobserved participants having a worse or better response than those observed. Reference‐based imputation draws imputed values with some reference to observed data in other groups of the trial, typically in other treatment arms. We illustrate the accessibility of these methods using data from a pediatric eczema trial and a chronic headache trial and provide Stata code to facilitate adoption. We discuss issues surrounding the choice of δ in δ ‐based sensitivity analysis. We also review the debate on variance estimation within reference‐based analysis and justify the use of Rubin's variance estimator in this setting, since as we further elaborate on within, it provides information anchored inference
Defining Efficacy Estimands in Clinical Trials: Examples Illustrating ICH E9(R1) Guidelines
This paper provides examples of defining estimands in real-world scenarios following ICH E9(R1) guidelines. Detailed discussions on choosing the estimands and estimators can be found in our companion papers. Three scenarios of increasing complexity are illustrated. The first example is a proof-of-concept trial in major depressive disorder where the estimand is chosen to support the sponsor decision on whether to continue development. The second and third examples are confirmatory trials in severe asthma and rheumatoid arthritis respectively. We discuss the intercurrent events expected during each trial and how they can be handled so as to be consistent with the study objectives. The estimands discussed in these examples are not the only acceptable choices for their respective scenarios. The intent is to illustrate the key concepts rather than focus on specific choices. Emphasis is placed on following a study development process where estimands link the study objectives with data collection and analysis in a coherent manner, thereby avoiding disconnect between objectives, estimands, and analyses.</p
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