Material migration and fuel retention studies during the JET carbon divertor campaigns

The first divertor was installed in the JET machine between 1992 and 1994 and was operated with carbon tiles and then beryllium tiles in 1994–5. Post-mortem studies after these first experiments demonstrated that most of the impurities deposited in the divertor originate in the main chamber, and that asymmetric deposition patterns generally favouring the inner divertor region result from drift in the scrape-off layer. A new monolithic divertor structure was installed in 1996 which produced heavy deposition at shadowed areas in the inner divertor corner, which is where the majority of the tritium was trapped by co-deposition during the deuterium-tritium experiment in 1997. Different divertor geometries have been tested since such as the Gas-Box and High-Delta divertors; a principle objective has been to predict plasma behaviour, transport and tritium retention in ITER. Transport modelling experiments were carried out at the end of four campaigns by puffing 13C-labelled methane, and a range of diagnostics such as quartz-microbalance and rotating collectors have been installed to add time resolution to the post-mortem analyses. The study of material migration after D-D and D-T campaigns clearly revealed important consequences of fuel retention in the presence of carbon walls. They gave a strong impulse to make a fundamental change of wall materials. In 2010 the carbon divertor and wall tiles were removed and replaced with tiles with Be or W surfaces for the ITER-Like Wall Project

An assessment of threats to terrestrial protected areas

Protected areas (PAs) represent a cornerstone of efforts to safeguard biodiversity, and if effective should reduce threats to biodiversity. We present the most comprehensive assessment of threats to terrestrial PAs, based on in-situ data from 1,961 PAs across 149 countries, assessed by PA managers and local stakeholders. Unsustainable hunting was the most commonly reported threat and occurred in 61% of all PAs, followed by disturbance from recreational activities occurring in 55%, and natural system modifications from fire or its suppression in 49%. The number of reported threats was lower in PAs with greater remoteness, higher control of corruption and lower human development scores. The main reported threats in developing countries were linked to overexploitation for resource extraction, while negative impacts from recreational activities dominated in developed countries. Our results show that many of the most serious threats to PAs are difficult to monitor with remote sensing, and highlight the importance of in situ threat data to inform the implementation of more effective biodiversity conservation in the global protected area estate

Business experience and start-up size: buying more lottery tickets next time around?

This paper explores the determinants of start-up size by focusing on a cohort of 6247 businesses that started trading in 2004, using a unique dataset on customer records at Barclays Bank. Quantile regressions show that prior business experience is significantly related with start-up size, as are a number of other variables such as age, education and bank account activity. Quantile treatment effects (QTE) estimates show similar results, with the effect of business experience on (log) start-up size being roughly constant across the quantiles. Prior personal business experience leads to an increase in expected start-up size of about 50%. Instrumental variable QTE estimates are even higher, although there are concerns about the validity of the instrument

Predicting new venture survival and growth: does the fog lift?

This paper investigates whether new venture performance becomes easier to predict as the venture ages: does the fog lift? To address this question we primarily draw upon a theoretical framework, initially formulated in a managerial context by Levinthal (Adm Sci Q 36(3):397–420, 1991) that sees new venture sales as a random walk but survival being determined by the stock of available resources (proxied by size). We derive theoretical predictions that are tested with a 10-year cohort of 6579 UK new ventures in the UK. We observe that our ability to predict firm growth deteriorates in the years after entry—in terms of the selection environment, the ‘fog’ seems to thicken. However, our survival predictions improve with time—implying that the ‘fog’ does lift

Kompetenznetz E-Learning Hessen

Mit dem Kompetenznetz e-learning-hessen.de vernetzen sich die hessischen Hochschulen mit Hilfe der Koordination und Unterstützung durch das httc und Förderung durch das Hessische Ministerium für Wissenschaft und Kunst rund um das Thema E-Learning. Dieser Beitrag beschreibt die Ziele des Netzwerks, dessen Maßnahmen und Elemente und die bisherigen Erfahrungen und seine Entwicklung seit dem Jahr 2000. Mit der abschließenden Bewertung werden Anhaltspunkte für eine erfolgreiche Vernetzung von Hochschulen und ein Ausblick auf die geplanten Aktivitäten des hessischen Netzwerkes in den nächsten Jahren gegeben. (DIPF/ Orig.

Thermal desorption spectrometry of beryllium plasma facing tiles exposed in the JET tokamak

Corrigendum: 10.1016/j.fusengdes.2018.08.007.The phenomena of retention and de-trapping of deuterium (D) and tritium (T) in plasma facing components (PFC) and supporting structures must be understood in order to limit or control total T inventory in larger future fusion devices such as ITER, DEMO and commercial machines. The goal of this paper is to present details of the thermal desorption spectrometry (TDS) system applied in total fuel retention assessment of PFC at the Joint European Torus (JET). Examples of TDS results from beryllium (Be) wall tile samples exposed to JET plasma in PFC configuration mirroring the planned ITER PFC is shown for the first time. The method for quantifying D by comparison of results from a sample of known D content was confirmed acceptable. The D inventory calculations obtained from Ion Beam Analysis (IBA) and TDS agree well within an error associated with the extrapolation from very few data points to a large surface area.Peer reviewe

Evidence-based intervention for preschool children with primary speech and language impairments: Child Talk - an exploratory mixed-methods study

BackgroundThe Child Talk study aimed to develop an evidence-based framework to support the decision-making of speech and language therapists (SLTs) as they design and plan interventions appropriate to the needs of individual children with primary speech and language impairments and their families. The need for early identification and effective intervention for these children continues to be a government policy priority because of the link between children’s early speech and language skills and their broader well-being and outcomes in later life. The first phase of Child Talk sought to map and describe current SLT practice for these children; identify and summarise the existing research evidence relating to practice; and investigate the perspectives of parents, early years practitioners, preschool children and ‘underserved’ communities on speech and language therapy. The second phase of Child Talk focused on the development of a toolkit – assessment tools, outcome measures and a data set – to support future service and economic evaluations of the framework.MethodsChild Talk adopted a mixed-methods design. Quantitative methods included surveys and investigated the prevalence and patterns of intervention usage; qualitative data collection methods included focus groups, interviews and reflection to investigate participants’ perspectives and understandings of interventions. Data analysis methods included descriptive and inferential statistics, thematic and content analysis and framework analysis. Participants were recruited nationally through six NHS sites, professional bodies, parent groups and advertising. Participants included SLTs (n = 677), parents (n = 84), preschool children (n = 24), early years practitioners (n = 31) and ‘underserved’ communities (n = 52).Key findingsSpeech and language therapy interventions were characterised in terms of nine themes, viewed as comprehensive and inclusive by practitioners. Relevant assessments, interventions and outcome domains were identified for the nine themes. Areas of tacit knowledge and underspecified processes contributed to variability in the detail of the framework. Systematic reviews identified 58 relevant and robust studies (from 55,271 papers retrieved from the initial literature search). The number of studies relevant to each theme varied from 1 to 33. Observational data on preschool children’s perspectives on speech and language therapy interventions revealed the dynamic nature of their interaction with different activities and people within therapy sessions. Parents’ experiences of speech and language therapy were generally positive although some reported that the rationale for therapy was not always clear. Parental perspectives in underserved communities suggested that, although parents were confident about how to support children’s language development, they were less informed about the nature of language impairments and the function of speech and language therapy. The availability of information regarding resources directed towards speech and language therapy services was poor. In particular, services lacked both a culture of collecting outcome data routinely and measures of professional input and costs associated with their activities.ConclusionA descriptive framework of SLT practice has been developed to support the discussions between therapists and families when making decisions regarding the selection of interventions and outcome measures. Further research is needed to address gaps in the intervention framework and evaluate its effectiveness and cost-effectiveness in improving outcomes for preschool children with primary speech and language impairments.Study registrationThis study is registered as PROSPERO CRD42013006369

‘Better late than never’: the interplay between green technology and age for firm growth

This paper investigates the relationship between green/non-green technologies and firm growth. By combining the literature on eco-innovations, industrial organisation and entrepreneurial studies, we examine the dependence of this relationship on the pace at which firms grow and the age of the firm. From a dataset of 5498 manufacturing firms in Italy for the period of 2000–2008, longitudinal fixed effects quantile models are estimated, in which the firm’s age is set to moderate the effects of green and non-green patents on employment growth. We find that the positive effect of green technologies on growth is greater than that of non-green technologies. However, this result does not apply to struggling and rapidly growing firms. With fast-growing (above the median) firms, age moderates the growth effect of green technologies. Inconsistent with the extant literature, this moderation effect is positive: firm experience appears important for the growth benefits of green technologies, possibly relative to the complexity of their management