US$39.50/£26.95 pbk (432 pages) ISBN 069111983X/0691117586

Although speciation research is an active field, there have, until now, been notably few books for researchers to keep up-to-date with this broad subject; suddenly, we’re spoilt for choice [1–3]. Gavrilets ’ book is a timely contribution: an overview, critique and synthesis of the massive body of population genetic theory on speciation. It conveys the excitement of current work, the depth of literature lost in the pre-database black hole, while also presenting an idiosyncratic and challenging view of the subject. The core of Fitness Landscapes and the Origin of Species is a detailed treatment of a wide range o

Evidence for Inefficient Selection Against Deleterious Mutations in Cytochrome Oxidase I of Asexual Bdelloid Rotifers

Evolutionary theory predicts that natural selection should be less efficient in asexually than in sexually reproducing organisms. Obligate asexuals are expected to adapt slowly to changing environments and to accumulate mildly deleterious mutations to their genomes, potentially explaining their typically short evolutionary lifespans. One group of animals that appear to challenge these ideas is the bdelloid rotifers, a large and ancient clade of obligate asexuals. Previous work has found no evidence for inefficient selection against deleterious mutations in protein-coding genes of bdelloids. However, these studies relied mostly on between-species comparisons and were therefore unable to detect mildly deleterious mutations that persist within populations but are removed by selection over longer time periods. Here, we test for inefficient purifying selection acting on the cytochrome oxidase I (cox1) mitochondrial gene in 3 clades of bdelloids. Patterns of variation are compared to those of two facultatively sexual clades: a monogonont rotifer (Brachionus) and a branchiopod crustacean (Daphnia). As predicted due to the strict linkage between mitochondrial and nuclear genomes, bdelloids exhibit higher frequencies of putatively deleterious amino acid polymorphism within populations than the two facultatively sexual clades. While the monophyly and age of bdelloids makes it hard to rule out other explanations for the observed differences, several possible confounding factors, such as differences in effective population size or patterns of codon usage, are shown not to explain the observed differences. We therefore conclude that bdelloid mitochondrial DNA variation does display the signature of inefficient selection expected of obligate asexuals

Investigating mirror system (MS) activity in adults with ASD when inferring others' intentions using both TMS and EEG

ASD is associated with mentalizing deficits that may correspond with atypical mirror system (MS) activation. We investigated MS activity in adults with and without ASD when inferring others’ intentions using TMS-induced motor evoked potentials (MEPs) and mu suppression measured by EEG. Autistic traits were measured for all participants. Our EEG data show, high levels of autistic traits predicted reduced right mu (8–10 Hz) suppression when mentalizing. Higher left mu (8–10 Hz) suppression was associated with superior mentalizing performances. Eye-tracking and TMS data showed no differences associated with autistic traits. Our data suggest ASD is associated with reduced right MS activity when mentalizing, TMS-induced MEPs and mu suppression measure different aspects of MS functioning and the MS is directly involved in inferring intentions

Magnetic transfer function entropy and the 2009 Mw = 6.3 L'Aquila earthquake (Central Italy)

Abstract. With the aim of obtaining a deeper knowledge of the physical phenomena associated with the 2009 L'Aquila (Central Italy) seismic sequence, culminating with a Mw = 6.3 earthquake on 6 April 2009, and possibly of identifying some kind of earthquake-related magnetic or geoelectric anomaly, we analyse the geomagnetic field components measured at the magnetic observatory of L'Aquila and their variations in time. In particular, trends of magnetic transfer functions in the years 2006–2010 are inspected. They are calculated from the horizontal to vertical magnetic component ratio in the frequency domain, and are very sensitive to deep and lateral geoelectric characteristics of the measurement site. Entropy analysis, carried out from the transfer functions with the so called transfer function entropy, points out clear temporal burst regimes of a few distinct harmonics preceding the main shock of the seismic sequence. A possible explanation is that they could be related to deep fluid migrations and/or to variations in the micro-/meso-fracturing that affected significantly the conductivity (ordered/disordered) distribution in a large lithospheric volume under the seismogenic layer below L'Aquila area. This interpretation is also supported by the analysis of hypocentres depths before the main shock occurrence

Flexible Commissioning: A prevention and access focused approach in Yorkshire and the Humber

No abstract available

Hydrologic data for the Idaho National Engineering Laboratory site, Idaho

The Idaho Chemical Processing Plant (ICPP) discharges low-level waste and chemical waste directly to the Snake River Plain aquifer through a 600-foot (180 meter) disposal well. Most of the radioactivity is removed by distillation and ion exchange prior to being discharged into the well. During 1971 to 1973, the well was used to dispose of 404 curies of radioactivity, of which 389 curies were tritium (96 percent). The average yearly discharge was about 300 million gallons (1.1 x 10$sup 9$ liters). The distribution of waste products in the Snake River Plain aquifer covers about 15 square miles (30 square kilometers). Since disposal began in 1952, the wastes have migrated about 5 miles (8 kilometers) downgradient from discharge points. The perched ground-water body contains tritium, chromium-51, cobalt-60, and strontium-90. Radionuclides are subject to radioactive decay, sorption, and dilution by dispersion in the aquifer. Chemical wastes are subject to sorption and dilution by dispersion. Waste plumes south of the ICPP containing tritium, sodium, and chloride have been mapped and all cover a similar area. The plumes follow generally southerly flow lines and are widely dispersed in the aquifer. The waste plume of strontium-90 covers a much smaller area of the aquifer, about 1.5 square miles (4 square kilometers). Based on the relatively small size of the plume, it would appear that the strontium-90 is sorbed from solution as it moves through the Snake River Plain aquifer. (auth

Magnetic transfer function entropy and the 2009 Mw = 6.3 L’Aquila earthquake (Central Italy)

With the aim of obtaining a deeper knowledge of the physical phenomena associated with the 2009 L’Aquila (Central Italy) seismic sequence, culminating with a Mw = 6.3 earthquake on 6 April 2009, and possibly of identifying some kind of earthquake-related magnetic or geoelectric anomaly, we analyse the geomagnetic field components measured at the magnetic observatory of L’Aquila and their variations in time. In particular, trends of magnetic transfer functions in the years 2006–2010 are inspected. They are calculated from the horizontal to vertical magnetic component ratio in the frequency domain, and are very sensitive to deep and lateral geoelectric characteristics of the measurement site. Entropy analysis, carried out from the transfer functions with the so called transfer function entropy, points out clear temporal burst regimes of a few distinct harmonics preceding the main shock of the seismic sequence. A possible explanation is that they could be related to deep fluid migrations and/or to variations in the micro-/meso-fracturing that affected significantly the conductivity (ordered/disordered) distribution in a large lithospheric volume under the seismogenic layer below L’Aquila area. This interpretation is also supported by the analysis of hypocentres depths before the main shock occurrence

CRISPR dynamics during the interaction between bacteria and phage in the first year of life

Gut microbiomes in infancy have a profound impact on health in adulthood. CRISPRs play an essential role in the interaction between bacteria and phages. However, the dynamics of CRISPRs in gut microbiomes during early life are poorly understood. In this study, using shotgun metagenomic sequencing data from 82 Swedish infants' gut microbiomes, 1882 candidate CRISPRs were identified, and their dynamics were analysed. We found large-scale turnover of CRISPRs and their spacers during the first year of life. As well as changes in relative abundance of the bacteria containing CRISPR, acquisition, loss and mutation of spacers were observed within the same CRISPR array sampled over time. Accordingly, the inferred interaction network of bacteria and phage was distinct at different times. This research underpins CRISPR dynamics and their potential role in the interaction between bacteria and phage in early life.</p