Mergers

Using small matched samples of companies which are, and are not, highly involved in acquisition in the period 1986-90, an investigation is mounted to ascertain whether "acquisitiveness" has any impact upon the remuneration of the top directors over and above what one would expect because of the growth in "size". The evidence suggests it does, if returns to share options are included in the measure of remuneration.

A critical review of Integrating Ubunifu, informal science, and community innovations in science classrooms in East Africa

This paper provides a brief critical review of the English executive summary to Integrating Ubunifu, informal science, and community innovations in science classrooms in East Africa (Semali et al. in Cult Stud Sci Educ 10:865–889, 2015. 10.1007/s11422-014-9640-x). It was written as an example of a critical review for an Erasmus + -funded training (http://ec.europa.eu/programmes/erasmus-plus/) in Research Methods for Ph.D. students at the African Centre of Excellence for Innovative Teaching and Learning Mathematics and Science in Rwanda (http://aceitlms.ur.ac.rw/) in October 2018

A Really Simple Guide to Quantitative Data Analysis

This purpose of this guide is to help university students, staff and researchers understand the basic principles of analysing the typical kinds of quantitative data they may collect or encounter in the course of their learning, teaching or research

Evaporation of a packet of quantized vorticity

A recent experiment has confirmed the existence of quantized turbulence in superfluid He3-B and suggested that turbulence is inhomogenous and spreads away from the region around the vibrating wire where it is created. To interpret the experiment we study numerically the diffusion of a packet of quantized vortex lines which is initially confined inside a small region of space. We find that reconnections fragment the packet into a gas of small vortex loops which fly away. We determine the time scale of the process and find that it is in order of magnitude agreement with the experiment.Comment: figure 1a,b,c and d, figure2, figure

Somatic mitochondrial DNA mutations in cancer escape purifying selection and high pathogenicity mutations lead to the oncocytic phenotype: pathogenicity analysis of reported somatic mtDNA mutations in tumors

BACKGROUND: The presence of somatic mitochondrial DNA (mtDNA) mutations in cancer cells has been interpreted in controversial ways, ranging from random neutral accumulation of mutations, to positive selection for high pathogenicity, or conversely to purifying selection against high pathogenicity variants as occurs at the population level. METHODS: Here we evaluated the predicted pathogenicity of somatic mtDNA mutations described in cancer and compare these to the distribution of variations observed in the global human population and all possible protein variations that could occur in human mtDNA. We focus on oncocytic tumors, which are clearly associated with mitochondrial dysfunction. The protein variant pathogenicity was predicted using two computational methods, MutPred and SNPs&GO. RESULTS: The pathogenicity score of the somatic mtDNA variants were significantly higher in oncocytic tumors compared to non-oncocytic tumors. Variations in subunits of Complex I of the electron transfer chain were significantly more common in tumors with the oncocytic phenotype, while variations in Complex V subunits were significantly more common in non-oncocytic tumors. CONCLUSIONS: Our results show that the somatic mtDNA mutations reported over all tumors are indistinguishable from a random selection from the set of all possible amino acid variations, and have therefore escaped the effects of purifying selection that act strongly at the population level. We show that the pathogenicity of somatic mtDNA mutations is a determining factor for the oncocytic phenotype. The opposite associations of the Complex I and Complex V variants with the oncocytic and non-oncocytic tumors implies that low mitochondrial membrane potential may play an important role in determining the oncocytic phenotype

How to Write a Literature Review

A literature review is not just a sequence of summaries or critiques of selected sources (this is known as an annotated bibliography). Rather, it should take the form of a critical discussion, showing insight and an awareness of differing arguments, theories, methods and findings. It should analyse and synthesise relevant published works

Advice on Reliability Analysis with Small Samples - Revised Version

Whilst it is common statistical advice not to attempt a reliability analysis with a sample size less than 300 a recent simulation study by Yurdugül indicates that this is possible in certain circumstances. The most common statistic used in reliability analysis is Cronbach’s alpha and an often quoted rule of thumb is a coefficient value above 0.7 is acceptable for psychological constructs. However, Cortina found that the size of a Cronbach’s alpha coefficient depends upon the number of items in the scale with scales with more items having higher coefficients. The advantage of carrying out a reliability analysis is that it can enable a researcher to treat a group of variables on the same subject as a single scale variable, reducing the complexity of further analysis and reducing the risk of Type I errors. However, student researchers often find it hard to obtain sample sizes of 300. The purpose of this worksheet is to advise students about how to go about trying to validate a scale with smaller sample sizes