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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
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
An economic perspective on the enforcement of credit arrangements: the case of daylight overdrafts in Fedwire
A fundamental concern for any lender is credit risk - the risk that a borrower will fail to fully repay a loan as expected. Thus, lenders want credit arrangements that are designed to compensate them for - and help them effectively manage - this type of risk. In certain situations, central banks engage in credit arrangements as lenders to banks, so they must manage their exposure to credit risk. This article discusses how the Federal Reserve manages its credit risk exposure associated with daylight overdrafts. The authors first present a simple economic framework for thinking about the causes of credit risk and the possible tools that lenders have to help them manage it. They then apply this framework to the Federal Reserve's Payments System Risk policy, which specifies the use of a variety of tools to manage credit risk. The study also analyzes a possible increase in the use of collateral as a credit risk management tool, as presented in a recent proposal by the Federal Reserve concerning changes to the Payments System Risk policy.Payment systems ; Federal Reserve System ; Credit ; Risk management
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
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
Current knowledge and recent advances in understanding metabolism of the model cyanobacterium Synechocystis sp. PCC 6803
Cyanobacteria are key organisms in the global ecosystem, useful models for studying metabolic and physiological processes conserved in photosynthetic organisms, and potential renewable platforms for production of chemicals. Characterising cyanobacterial metabolism and physiology is key to understanding their role in the environment and unlocking their potential for biotechnology applications. Many aspects of cyanobacterial biology differ from heterotrophic bacteria. For example, most cyanobacteria incorporate a series of internal thylakoid membranes where both oxygenic photosynthesis and respiration occur, while CO2 fixation takes place in specialised compartments termed carboxysomes. In this review, we provide a comprehensive summary of our knowledge on cyanobacterial physiology and the pathways in Synechocystis sp. PCC 6803 (Synechocystis) involved in biosynthesis of sugar-based metabolites, amino acids, nucleotides, lipids, cofactors, vitamins, isoprenoids, pigments and cell wall components, in addition to the proteins involved in metabolite transport. While some pathways are conserved between model cyanobacteria, such as Synechocystis, and model heterotrophic bacteria like Escherichia coli, many enzymes and/or pathways involved in the biosynthesis of key metabolites in cyanobacteria have not been completely characterised. These include pathways required for biosynthesis of chorismate and membrane lipids, nucleotides, several amino acids, vitamins and cofactors, and isoprenoids such as plastoquinone, carotenoids, and tocopherols. Moreover, our understanding of photorespiration, lipopolysaccharide assembly and transport, and degradation of lipids, sucrose, most vitamins and amino acids, and heme, is incomplete. We discuss tools that may aid characterisation of cyanobacterial metabolism, notably CyanoSource, a barcoded library of targeted Synechocystis mutants, which will significantly accelerate characterisation of individual proteins
Cybermedicine: The Benefits and Risks of Purchasing Drugs Over The Internet
In today\u27s rapidly changing world of e-commerce, almost anything can be bought over the Internet and delivered right to your front door. Virtually every day there is news of yet another company selling some type of product online. Included in this barrage of products is prescription medication. Not only is it possible to order prescription medication over the Internet, in some cases it is not necessary to be examined, or even to consult with a physician. ~ To some, this new type of cybermedicine is an affront to traditional medicine, as well as potentially dangerous to consumers. In addition, the availability of medication over the Internet presents a vexing and complex challenge to state and federal agencies charged with enforcing drug laws. This problem has recently led to the Commerce Committee of the U.S. House hold hearings on the subject in an effort to understand what is involved with this new type of medicine, and which federal and state agencies have jurisdiction over online prescription sales. Unfortunately, it still remains unclear as to exactly which agencies do have jurisdiction. Nevertheless, as Congress and individual states rush to address the issue, entrepreneurs and drugstore chains are racing to establish the next on-line pharmacy.
For consumers, the idea of dealing with a cyber-pharmacy is appealing for several reasons. Lower cost and convenience for elderly people or those living in rural areas, as well as the ability to privately consult with a pharmacist are just a few of the benefits often cited. IO But in addition to these advantages, there are still substantial risks. These include easy access to illegal or unapproved drugs, medication offered without a prescription, and drugs marketed with fake health claims. As the confusion over online pharmacies mounts, one thing is clear; this new type of medicine is growing at a substantial rate.
This comment will attempt to define and explain the tremendous growth of online pharmacies. Next it will examine pending legislation and current cases relating to the sale of medication online. Finally this comment will examine the risks and benefits of ordering medications online, and what consumers should do to protect themselves as well as comply with the Jaw
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