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Making sense of doctoral training reforms in the social sciences:
Educational reforms are increasingly driven by political and economic forces beyond the university. In this paper I describe how the policy initiatives of the United Kingdom’s Economic and Social Research Council (ESRC) have steadily reshaped the length, content and structure of doctoral education in the social sciences. This history of the Council’s willingness to respond to national and international policy concerns about the doctorate dates back to the early years of the Thatcher Government in the 1980s. As well as redefining the doctoral student experience, this interventionist policy environment potentially challenges the institutional autonomy of academics and others involved in educational development. In this article I explore the implications of this for doctoral training provision, and for the meaning of educational development itself. I end by pointing to the possibilities for policy ‘activism’ in responding to these changes
Temporal tracking of mineralization and transcriptional developments of shell formation during the early life history of pearl oyster Pinctada maxima
Molluscan larval ontogeny is a highly conserved process comprising three principal developmental stages. A characteristic unique to each of these stages is shell design, termed prodissoconch I, prodissoconch II and dissoconch. These shells vary in morphology, mineralogy and microstructure. The discrete temporal transitions in shell biomineralization between these larval stages are utilized in this study to investigate transcriptional involvement in several distinct biomineralization events. Scanning electron microscopy and X-ray diffraction analysis of P. maxima larvae and juveniles collected throughout post-embryonic ontogenesis, document the mineralogy and microstructure of each shelled stage as well as establishing a timeline for transitions in biomineralization. P. maxima larval samples most representative of these biomineralization distinctions and transitions were analyzed for differential gene expression on the microarray platform PmaxArray 1.0. A number of transcripts are reported as differentially expressed in correlation to the mineralization events of P. maxima larval ontogeny. Some of those isolated are known shell matrix genes while others are novel; these are discussed in relation to potential shell formation roles. This interdisciplinary investigation has linked the shell developments of P. maxima larval ontogeny with corresponding gene expression profiles, furthering the elucidation of shell biomineralization
Heavy metals and nitrogen in mosses: spatial patterns in 2010/2011 and long-term temporal trends in Europe
Naturally-occurring mosses have been sampled across Europe to monitor
the deposition of heavy metals and nitrogen from the air. This survey has been
repeated at five-yearly intervals since 1990 for heavy metals and since 2005 for
nitrogen. In 2010/2011, mosses were collected at ca. 4,500 sites in 25 countries
for heavy metals and ca. 2,400 sites in 15 countries for nitrogen. In general, the
lowest concentrations in mosses were found in northern Europe for both heavy
metals and nitrogen. The highest concentrations of heavy metals were often
observed in south-eastern Europe, whereas the highest concentrations of
nitrogen were found in parts of western and central Europe. Europe-wide the
concentration of lead (77% decline), vanadium (57%), iron (52%) and cadmium
(51%) has declined the most since 1990, whereas the concentration of copper
has declined the least (11% decline). Since 1995, the concentration of arsenic and
mercury has declined by 26% and 23% respectively. The nitrogen concentration
in mosses has hardly changed since 2005
Kinetics of liquid phase semiconductor photoassisted reactions : supporting observations for a pseudo-steady-state model
The kinetics of liquid phase semiconductor photocatalytic and photoassisted reactions are an area of some debate, reignited recently by an article by Ollis1 in which he proposed a simple pseudo-steady-state model to interpret the Langmuir-Hinshelwood type kinetics, commonly observed in such systems. In the current article, support for this model, over other models, is provided by a reinterpretation of the results of a study, reported initially in 1999,2 of the photoassisted mineralization of 4-chlorophenol, 4-CP, by titania films and dispersions as a function of incident light intensity, I. On the basis of this model, these results indicate that 4-CP is adsorbed more strongly on P25 TiO2 when it is in a dispersed, rather than a film form, due to a higher rate constant for adsorption, k1. In addition, the kinetics of 4-CP removal appear to depend on Iâ, where â ) 1 or 0.6 for when the TiO2 is in a film or a dispersed form, respectively. These findings are discussed both in terms of the pseudo-steady-state model and other popular kinetic models
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