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Global mapping efforts to date have relied on vague and oversimplified definitions of “abandoned” agricultural land which results in overestimates of the land area that is likely to support persistent increases in forest cover and associated carbon sequestration. We propose a new conceptualization of abandoned agricultural land that incorporates changes in landholding status over time into determining whether land should be considered as abandoned. In order to develop more realistic estimates of the amount of land available for reforestation, we recommend clearly defining how abandoned land is categorized, discerning who owns and has rights to use the land, and combining remotely sensed data with household/stakeholder surveys to understand landowner motivations for not cropping or grazing land.

Aim: Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location: Tropical and subtropical moist forests. Time period: Current. Major taxa studied: Palms (Arecaceae). Methods: We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results: On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions: Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.

Gabriel Tremblay,1 Qayyim Said,2 Anuja Nidumolu Roy,2 Beilei Cai,2 Shan Ashton Garib,1 Jaclyn Hearnden,1 Anna Forsythe1 1Purple Squirrel Economics, New York, NY, USA; 2Novartis Pharmaceutical Corporation, East Hanover, NJ, USACorrespondence: Gabriel TremblayPurple Squirrel Economics, 4 Lexington Ave, Suite 15K, New York, NY 10010, USATel +1 418 317 5627Email gabrieltremblay@pshta.comBackground: Severe aplastic anemia (SAA) is a rare autoimmune condition resulting in low blood cell counts across lineages. Immunosuppressive therapy (IST) has demonstrated low response, toxicity, and risk of transformation. In a Phase I/II trial, the addition of eltrombopag to first-line IST increased response rates relative to an IST-only historical cohort.Methods: A model was developed to estimate the budget impact of treating SAA with eltrombopag-based therapy from a US private healthcare system perspective. A simulated cohort of newly diagnosed SAA patients based on the total US population received 6 months of IST ± eltrombopag and were followed for 1 year, with mutually exclusive patient cohorts entering in years 1, 2, and 3. The model assessed the budget impact of first-year treatment for each cohort without considering subsequent years. At 6 months, responders in either arm received maintenance therapy (low-dose cyclosporine), and non-responders received 6 months of second-line eltrombopag monotherapy. Costs considered included first-line, maintenance, and second-line therapy, administration, routine care, mortality, and adverse events (AEs). All cost data were reported in 2018 US dollars.Results: The annual incidence of aplastic anemia was 0.000234%, with 83.8% of cases assumed to be SAA. Based on trial data, 94% of patients receiving eltrombopag and IST responded versus 66% of patients receiving IST, with a 0.3% reduction in the annual risk of mortality for the eltrombopag + IST group. Use of first-line eltrombopag in a model SAA population based on the total US population increased overall costs by $50 million over 3 years. First-line drug costs accounted for an increase of $69 million, while improved response produced $19 million in secondary therapy cost savings. Sensitivity analyses confirmed the robustness of the analysis.Conclusion: High response rates combined with reduced rescue medication use and mortality in patients treated with eltrombopag and IST mediated higher medication costs.Keywords: budget impact analysis, costs, eltrombopag, severe aplastic anemia, thrombopoietin receptor agonist, United States

Neurogenesis in the adult hippocampus involves activation of quiescent neural stem cells (NSCs) to yield transiently amplifying NSCs, progenitors, and, ultimately, neurons that affect learning and memory. This process is tightly controlled by microenvironmental cues, although a few endogenous factors are known to regulate neuronal differentiation. Astrocytes have been implicated, but their role in juxtacrine (that is, cell-cell contact dependent) signaling in NSC niches has not been investigated. We found that ephrin-B2 presented from rodent hippocampal astrocytes regulated neurogenesis in vivo. Furthermore, clonal analysis in NSC fate-mapping studies revealed a previously unknown role for ephrin-B2 in instructing neuronal differentiation. In addition, ephrin-B2 signaling, transduced by EphB4 receptors on NSCs, activated β-catenin in vitro and in vivo independently of Wnt signaling and upregulated proneural transcription factors. Ephrin-B2(+) astrocytes therefore promote neuronal differentiation of adult NSCs through juxtacrine signaling, findings that advance our understanding of adult neurogenesis and may have future regenerative medicine implications.

Our understanding of the transition from school to work has traditionally been underpinned by a three-stage model. This is one in which the first stage is a preparatory one, where the focus is on school, followed by a second transition stage and ending in a third stage, the successful entry to work. This is a model that has been challenged by work from the "cultural studies" school but still informs much contemporary work. The study of freelance dancers' entry into work reveals a very different experience of the transition. Rather than a sequence of experiences of school, preparation for work and then entry into established employment, the dancer's experience is one of coterminus experiences of work, vocational training and family life that can start before the entry into primary education. This represents a serious challenge to the three-stage model as a general model for conceptualising transitions. Using the experience of the dancers and building on the work of Becker and Wyn, this paper explores how the concept of belonging points the way forward towards a more comprehensive conceptualisation of the transition.

In a mathematical examination on paper, partial credit is normally awarded for an answer that is not correct, but, nevertheless, contains some of the correct working. Assessment on computer normally marks an incorrect answer wrong and awards no marks. This can lead to discrepancies between marks awarded for the same examination given in the two different media. The current paper presents possible solutions to this problem and the results of experiments designed to test how successful these solutions are in practice. In light of the findings, developments to the assessment engine have been made and some questions redesigned for use in real automated examinations. The results were obtained as part of the Project for Assessments in Scotland using Information Technology (PASS-IT): a major collaborative programme involving the leading educational agencies in Scotland (see http://www.pass-it.org.uk for more details). PASS-IT has demonstrated that the computer can help measure lower order student skill profiles provided the computer assessment package is sophisticated enough. Optional steps are required to mimic partial credit; randomisation of parameters is needed for practice and the avoidance of copying; the ability to capture and mark automatically mathematical expressions and short free text responses; and the delivery in a number of feedback modes are all vital ingredients of an automatic assessment system. PASS-IT has shown how to ensure that education drives technology and not vice versa. Finally, collaboration has been paramount within PASS-IT and should continue. No single group has all the keys to unlock the future of computer-aided assessment. Scotland is well placed to move forward and e-assess where its students e-learn in a large range of subjects such as those delivered via the SCHOLAR Programme (see http://scholar.hw.ac.uk). It should be done too by ensuring that teachers remain central to the learning cycle by supporting the demanding work they do through the supply of suitably filtered data on student performance. Special educational needs can also be addressed more effectively by the use of technology.

This article presents results of a comparison between paper and computer tests of ability in Chemistry and Computing. A statistical model is employed to analyse the experimental data from almost 200 candidates. It is shown that there is no medium effect when specific traditional paper examinations in Chemistry and Computing are transferred into electronic format. The effect of rewording for computer-delivered test questions is also investigated and again the conclusion is that no evidence of a difference could be found. These results were obtained as part of the Project for Assessments in Scotland using Information Technology (PASS-IT).

Assessment and learning are two sides of the same coin (Ramsden, 1992, Biggs, 1999) and their relationship has also been likened to the participants in a three-legged race (Harding & Craven, 2001). The aim of this article is to explore the potential of e-assessment to provide solutions to some of the challenges for e-learning. Drawing on decades of development in the United Kingdom higher education sector, this article addresses key issues for e-learning, in particular the support of learners through formative assessment and detailed feedback and the benefits of, and barriers to, summative e-assessment for both learners and organisations. Various groups have pioneered the delivery of e-assessment in the United Kingdom since the mid-1980s. Early projects and tools include: the Computer-aided Learning in Mathematics (CALM) Project team at Heriot-Watt University (Beevers, Foster & McGuire, 1989), Coursemaster computer science programming software at Nottingham University (Benford, Burke, & Foxley, 1992; Foxley, Higgins, Tsintsifas, & Symoniedes, 1999) and various language tools, such as LUISA at Leeds University, among others (Bull, 1993). The tools of e-assessment have advanced dramatically. Systems are now capable of supplying a range of question types well beyond the multiple-choice format, incorporating images, multimedia, and animation. In many universities e-assessment is used for both formative and summative assessment in a variety of disciplines (Stephens & Mascia, 1995, Bull & McKenna, 2000, 2003; Mackenzie, 1999). Internationally, there have been similar developments in Australia (Robinson, 1999; Morgan & O'Reilly, 1999; Daziel, 2001), Europe (Deemeersseman, Bert & Jos, 2001, Van Rentergem, Cosemans, Verburgh, & Wils, 2002; Geurts, 2001; Guildford Educational Services [GES], 1999) and especially in the United States where the use of large-scale e-assessment is widespread across a range of sectors (Bennett, 1998; Drasgow & Olsen-Buchanan, 1999; Burstein, Lacock, & Swartz, 2001; Leacock & Chodorow, 2000). Practitioners and developers frequently debate the effective pedagogical use of e-assessment. Themes include the potential to support and enhance learning through structured and directive formative assessment and feedback and the capabilities of e-assessment to test different types of skills effectively and reliably. It is generally accepted that Bloom (Bloom & Krathwohl, 1956/1964) provided a sensible taxonomy of educational objectives that apply to most academic subjects. Currently in practice, e-assessment can be applied to test the minimum competencies (knowledge, comprehension, and application), and attempts are already appearing to provide automatic testing for the extended competencies of analysis, synthesis, and evaluation. In Scottish secondary education, National Assessment Bank (NAB) tests measure the minimum competencies. The recently funded project, PASS-IT, is working to achieve the automatic delivery of National Assessment Bank items in a range of subjects directly into schools and colleges. PASS-IT (http://www.pass-it.org.uk) brings together major Scottish interests with a common goal to investigate how best to exploit e-assessment to enhance flexibility, improve attainment, and support teaching and learning. PASS-IT combines the key players of the Scottish Qualifications Authority, Learning and Teaching Scotland, the BBC, the Scottish Further Education Unit, and the Scottish Centre for Research into On-Line Learning and Assessment. PASS-IT is creating e-assessment for a range of National and Higher National provision and tests for one area of the 5-14 curriculum, supporting the first National Priority in school education--Achievement and Attainment. The project has a keen awareness of related issues, such as interoperability (http://www.impsproject.org), evaluations of the use of steps for partial credit (Beevers, Youngson, McGuire, Wild, & Fiddes, 1999), the significance of the medium in test delivery (Fiddes, Korabinski, McGuire, Youngson, & McMillan, 2002) and the emerging guidelines concerning security of computer examinations (UK BS7988 Code of Practice). PASS-IT is experimenting with novel approaches to question design and structure, the role of feedback to support learning, invigilation leading to more secure examinations on demand and the concept of anywhere, anytime testing. While no prior assumptions are being made about either the feasibility or desirability of e-assessment this project is seeking to develop a model for national summative assessment, which can be adapted for use with a number of assessment approaches, and can illustrate the relationship between formative and summative assessment.