Data mining approach identifies research priorities and data requirements for resolving the red algal tree of life

Background. The assembly of the tree of life has seen significant progress in recent years but algae and protists have been largely overlooked in this effort. Many groups of algae and protists have ancient roots and it is unclear how much data will be required to resolve their phylogenetic relationships for incorporation in the tree of life. The red algae, a group of primary photosynthetic eukaryotes of more than a billion years old, provide the earliest fossil evidence for eukaryotic multicellularity and sexual reproduction. Despite this evolutionary significance, their phylogenetic relationships are understudied. This study aims to infer a comprehensive red algal tree of life at the family level from a supermatrix containing data mined from GenBank. We aim to locate remaining regions of low support in the topology, evaluate their causes and estimate the amount of data required to resolve them. Results. Phylogenetic analysis of a supermatrix of 14 loci and 98 red algal families yielded the most complete red algal tree of life to date. Visualization of statistical support showed the presence of five poorly supported regions. Causes for low support were identified with statistics about the age of the region, data availability and node density, showing that poor support has different origins in different parts of the tree. Parametric simulation experiments yielded optimistic estimates of how much data will be needed to resolve the poorly supported regions (ca. 103 to ca. 104 nucleotides for the different regions). Nonparametric simulations gave a markedly more pessimistic image, some regions requiring more than 2.8 105 nucleotides or not achieving the desired level of support at all. The discrepancies between parametric and nonparametric simulations are discussed in light of our dataset and known attributes of both approaches. Conclusions. Our study takes the red algae one step closer to meaningful inclusion in the tree of life. In addition to the recovery of stable relationships, the recognition of five regions in need of further study is a significant outcome of this work. Based on our analyses of current availability and future requirements of data, we make clear recommendations for forthcoming research.

Algorithmic computation of knot polynomials of secondary structure elements of proteins

The classification of protein structures is an important and still outstanding problem. The purpose of this paper is threefold. First, we utilize a relation between the Tutte and homfly polynomial to show that the Alexander-Conway polynomial can be algorithmically computed for a given planar graph. Second, as special cases of planar graphs, we use polymer graphs of protein structures. More precisely, we use three building blocks of the three-dimensional protein structure-alpha-helix, antiparallel beta-sheet, and parallel beta-sheet-and calculate, for their corresponding polymer graphs, the Tutte polynomials analytically by providing recurrence equations for all three secondary structure elements. Third, we present numerical results comparing the results from our analytical calculations with the numerical results of our algorithm-not only to test consistency, but also to demonstrate that all assigned polynomials are unique labels of the secondary structure elements. This paves the way for an automatic classification of protein structures.

Sequence changes in predicted promoter elements of STK11/LKB1 are unlikely to contribute to Peutz-Jeghers syndrome

Background: Germline mutations or large-scale deletions in the coding region and splice sites of STK11/LKB1 do not account for all cases of Peutz-Jeghers syndrome (PJS). It is conceivable that, on the basis of data from other diseases, inherited variation in promoter elements of STK11/LKB1 may cause PJS.

Behaviour of joints with bonded-in steel bars loaded parallel to the grain of timber elements

Within the sustainability context, this paper is extremely timely and relevant. The research focuses on broadening the use of timber structurally. The insight gained forms the basis for sustainable, fire resistant, economic and aesthetically pleasing moment resistant connections in timber.

Exploring Innovative Methodologies in time and place to analyze child protection documents as elements of practice

This paper aims to demonstrate how a derived approach to case file analysis, influenced by the work of Michel Foucault and Dorothy E.Smith, can offer innovative means by which to study the relations between discourse and practices in child welfare. The article explores text-based forms of organization in histories of child protection in Finland and in Northern Ireland. It is focused on case file records in different organizational child protection contexts in two jurisdictions. Building on a previous article (Author 1 & 2: 2011), we attempt to demonstrate the potential of how the relations between practices and discourses –a majorly important theme for understanding child welfare social work – can be effectively analysed using a combination of two approaches This article is based on three different empirical studies from our two jurisdictions Northern Ireland (UK) and Finland; one study used Foucault; the other Smith and the third study sought to combine the methods. This article seeks to report on ongoing work in developing, for child welfare studies, ‘a history that speaks back’ as we have described it.