The determinants of performance appraisal systems: A note (Do Brown and Heywood's results for Australia hold up for Britain?)

This article offers a replication for Britain of Brown and Heywood's analysis of the determinants of performance appraisal in Australia. Although there are some important limiting differences between our two datasets - the Australia Workplace Industrial Relations Survey (AWIRS) and the Workplace Employment Relations Survey (WERS) - we reach one central point of agreement and one intriguing shared insight. First, performance appraisal is negatively associated with tenure: where employers cannot rely on the carrot of deferred pay or the stick of dismissal to motivate workers, they will tend to rely more on monitoring, ceteris paribus. Second, employer monitoring and performance pay may be complementary. However, consonant with the disparate results from the wider literature, there is more modest agreement on the contribution of specific human resource management practices, and still less on the role of job control.

The Ectocarpus genome and the independent evolution of multicellularity in brown algae

Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related(1). These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. Brown algae are also one of only a small number of eukaryotic lineages that have evolved complex multicellularity (Fig. 1). We report the 214 million base pair (Mbp) genome sequence of the filamentous seaweed Ectocarpus siliculosus (Dillwyn) Lyngbye, a model organism for brown algae(2-5), closely related to the kelps(6,7) (Fig. 1). Genome features such as the presence of an extended set of light-harvesting and pigment biosynthesis genes and new metabolic processes such as halide metabolism help explain the ability of this organism to cope with the highly variable tidal environment. The evolution of multicellularity in this lineage is correlated with the presence of a rich array of signal transduction genes. Of particular interest is the presence of a family of receptor kinases, as the independent evolution of related molecules has been linked with the emergence of multicellularity in both the animal and green plant lineages. The Ectocarpus genome sequence represents an important step towards developing this organism as a model species, providing the possibility to combine genomic and genetic(2) approaches to explore these and other(4,5) aspects of brown algal biology further.

Role of endoreduplication and apomeiosis during parthenogenetic reproduction in the model brown alga Ectocarpus

The filamentous brown alga Ectocarpus has a complex life cycle, involving alternation between independent and morphologically distinct sporophyte and gametophyte generations. In addition to this basic haploid–diploid life cycle, gametes can germinate parthenogenetically to produce parthenosporophytes. This article addresses the question of how parthenosporophytes, which are derived from a haploid progenitor cell, are able to produce meiospores in unilocular sporangia, a process that normally involves a reductive meiotic division.
We used flow cytometry, multiphoton imaging, culture studies and a bioinformatics survey of the recently sequenced Ectocarpus genome to describe its life cycle under laboratory conditions and the nuclear DNA changes which accompany key developmental transitions.
Endoreduplication occurs during the first cell cycle in about one-third of parthenosporophytes. The production of meiospores by these diploid parthenosporophytes involves a meiotic division similar to that observed in zygote-derived sporophytes. By contrast, meiospore production in parthenosporophytes that fail to endoreduplicate occurs via a nonreductive apomeiotic event.
Our results highlight Ectocarpus’s reproductive and developmental plasticity and are consistent with previous work showing that its life cycle transitions are controlled by genetic mechanisms and are independent of ploidy.

Cell cycles and endocycles in the model brown seaweed, Ectocarpus siliculosus

The recent announcement of the first genome sequence of a brown macroalga, the filamentous Ectocarpus, has been accompanied by a number of companion papers in New Phytologist. In a paper which contributes to this special issue, we classified the core cell cycle components of Ectocarpus, comparing them to the previously studied cell cycle components of diatoms. We then carried out fluorescence microscopy experiments to show that the Ectocarpus cell cycle could be deregulated during early development to give endopolyploid adults. We discuss here how our findings complement recent studies on endopolyploidy in plant and algal systems.

Review of The New Punitiveness: Trends, Theories, Perspectives , edited by J Pratt, D Brown, M Brown, S Hallsworth and W Morrison

Book Review

The interactions of coal with CO2 and its effects on coal structure

The interactions of coal with CO2 at pressures of up to 30 bar concerning mechanisms of diffusion, the strength of interactions, and the irreversibility of uptake for the permanent disposal of CO2 into coal fields have been studied. Differential scanning calorimetry was used to investigate coal/CO2 interactions for North Dakota, Wyodak, Illinois No. 6, and Pittsburgh No. 8 coals. It was found that the first interactions of CO2 with coals led to strongly bound carbon dioxide on coal. Energy values attributed to the irreversible storage capacity for CO2 on coals were determined. The lowest irreversible sorption energy was found for North Dakota coal (0.44 J/g), and the highest value was for the Illinois No. 6 coal (8.93 J/g). The effect of high-pressure CO2 on the macromolecular structure of coal was also studied by means of differential scanning calorimetry. It was found that the temperature of the second-order phase transition of Wyodak coal decreases with an increase in CO2 pressure significantly, indicating that high-pressure CO2 diffuses through the coal matrix, causes significant plasticization effects, and changes the macromolecular structure of the Wyodak coal. Desorption characteristics of CO2 from the Pittsburgh No. 8 coal were studied by temperature-programmed desorption mass spectrometry. It was found that CO2 desorption from the coal is an activated process and follows a first-order kinetic model. The activation energy for CO2 desorption from the Pittsburgh No. 8 coal increased with the preadsorbed CO2 pressure, indicating that CO2 binds more strongly and demands more energy to desorb from the Pittsburgh No. 8 coal at higher pressures.

Thermodynamical studies of irreversible sorption of CO2 by Wyodak coal

Differential scanning calorimetry (DSC), temperature programmed desorption mass spectrometry (TPD-MS) and small angle neutron scattering (SANS) were used to investigate CO2 uptake by the Wyodak coal. The adsorption of carbon dioxide on Wyodak coal was studied by DSC. The exotherms evident at low temperatures are associated with the uptake of CO2 suggesting that carbon dioxide interacts strongly with the coal surface. The reduction in the value of the exotherms between the first and second runs for the Wyodak coal suggests that some CO2 is irreversibly bound to the structure even after heating to 200 °C DSC results also showed that adsorption of CO2 on the coal surface is an activated process and presumably at the temperature of the exotherms there is enough thermal energy to overcome the activation energy for adsorption. The adsorption process is instantly pursued by much slower diffusion of the gas molecules into the coal matrix (absorption). Structural rearrangement in coal by CO2 is examined by change in the glass transition temperature of coal after CO2 uptake at different pressures. The amount of gas dissolved in the coal increases with increasing CO2 pressure. TPD-MS showed that CO2 desorption from the Wyodak coal follows a first order kinetic model. Increase in the activation energy for desorption with pre-adsorbed CO2 pressure suggests that higher pressures facilitate the transport of CO2 molecules through the barriers therefore the amount of CO2 uptake by the coal is greater at higher pressures and more attempts are required to desorb CO2 molecules sorbed at elevated pressures. These conclusions were further confirmed by examining the Wyodak coal structure in high pressure CO 2 by SANS.

Study of structural change in Wyodak coal in high pressure CO2 by small-angle neutron scattering

Small angle neutron scattering (SANS) has been applied to examine the effect of high pressure CO2 on the structure of Wyodak coal. Significant decrease in the scattering intensities upon exposure of the coal to high pressure CO2 showed that high pressure CO2 rapidly adsorbs on the coal and reaches to all pores in the structure. This is confirmed by strong and steep exothermic peaks observed on DSC scans during coal/ CO2 interactions. In situ small angle neutron scattering on coal at high pressure CO2 atmosphere showed an increase in scattering intensities with time suggesting that after adsorption, high pressure CO2 immediately begins to diffuse into the coal matrix, changes the macromolecular structure of the coal, swells the matrix and probably creates microporosity in coal structure by extraction of volatile components from coal. Significant decrease in the glass transition temperature of coal caused by high pressure CO2 also confirms that CO2 at elevated pressures dissolve in the coal matrix, results in significant plasticization and physical rearrangement of the coal’s macromolecular structure.

WASP-30b: A 61 M Jup Brown Dwarf Transiting a V = 12, F8 Star

We report the discovery of a 61-Jupiter-mass brown dwarf (BD), which transits its F8V host star, WASP-30, every 4.16 days. From a range of age indicators we estimate the system age to be 1-2 Gyr. We derive a radius (0.89 ± 0.02 R Jup) for the companion that is consistent with that predicted (0.914 R Jup) by a model of a 1 Gyr old, non-irradiated BD with a dusty atmosphere. The location of WASP-30b in the minimum of the mass-radius relation is consistent with the quantitative prediction of Chabrier & Baraffe, thus confirming the theory.

Detection of Mixing Dynamics During Pumping of a Flooded Coal Mine

In complex hydrogeological environments the effective management of groundwater quality problems by pump-and-treat operations can be most confidently achieved if the mixing dynamics induced within the aquifer by pumping are well understood. The utility of isotopic environmental tracers (C-, H-, O-, S-stable isotopic analyses and age indicators—14C, 3H) for this purpose is illustrated by the analysis of a pumping test in an abstraction borehole drilled into flooded, abandoned coal mineworkings at Deerplay (Lancashire, UK). Interpretation of the isotope data was undertaken conjunctively with that of major ion hydrochemistry, and interpreted in the context of the particular hydraulic setting of flooded mineworkings to identify the sources and mixing of water qualities in the groundwater system. Initial pumping showed breakdown of initial water quality stratification in the borehole, and gave evidence for distinctive isotopic signatures (d34S(SO4) ~= -1.6‰, d18O(SO4) ~= +15‰) associated with primary oxidation of pyrite in the zone of water table fluctuation—the first time this phenomenon has been successfully characterized by these isotopes in a flooded mine system. The overall aim of the test pumping—to replace an uncontrolled outflow from a mine entrance in an inconvenient location with a pumped discharge on a site where treatment could be provided—was swiftly achieved. Environmental tracing data illustrated the benefits of pumping as little as possible to attain this aim, as higher rates of pumping induced in-mixing of poorer quality waters from more distant old workings, and/or renewed pyrite oxidation in the shallow subsurface.

'Seven Devils': Gerald Griffin's 'The Brown Man' and the making of Irish gothic

This article explores Gerald Griffin's intriguing and neglected short story 'The Brown Man', arguing that it challenges and unsettles current critical understanding of the nature of Irish Gothic.