Alley coppice: combining willow SRC with poplar and cherry trees

PosterShort Rotation willow Coppice (SRC) is an important source of biomass energy in Ireland. Growing and intensively managing trees at wide spacing generates high value timber, sequesters carbon and delivers other ecosystem services. The alley coppice system combines the production of SRC with high value timber trees. Three alley coppice experiments were established to study the interaction of SRC with high value timber trees. In Experiment 1 the cherry variety - willow interaction is investigated: 5 willow varieties (and a mixture of all 5); (‘Resolution’, ‘Beagle’, ‘Endeavour’, ‘Olaf’ and ‘Terra Nova’) interact with rows of clonal wild cherry: ‘Neso’, ‘Pluto’, ‘Saturn’, ‘Hermes’ and ‘Concordia’ and one control of seedlings. The willow is planted in double rows 0.75m by 1.5m apart. Cherry trees are planted at an intra-row tree to tree spacing of 2.5m and inter-row spacing of 12.75m and alley widths of 1m & 2 m. In Experiment 2, 18 year old poplars (‘Hoogwoorst’, ‘Beaupre’, ‘Gebec’ ‘Trichobel’) are 5m apart in 14m wide alleys, planted with each of the 7 willow varieties (6 monoculture – as above in Experiment 1 but including ‘Tora’ & one mixed willow treatment simulating commercial planting). In Experiment 3, cherry are inter-planted along an existing commercial SRC as single tree plots in a linear randomised design. Cherry trees are 2.5m apart in rows; each is 2.5 m from nearest willow stool. Each block contains 5 sub plots. Each sub plot contains 26 tree genotypes: 22 German varieties, 2 French varieties and seedlings as controls. For each experiment the growth and yield of the tree and SRC components and their interactions will be measured and evaluated

Social and economical evaluation of innovative alley coppice systems mixing timber trees with bioenergy wood crops in agroforestry systems

PosterAlley coppice (AC) is an innovative agroforestry system where high value timber trees in lines are intercropped with bioenergy short rotation coppice (SRC). AC potentially provides several production and environmental benefits, although so far these are poorly investigated. Thus, research on farmer interest in AC systems, and preliminary economic evaluations, have been made on the AgroCop European project (www.agrocop.com). A questionnaire was conducted with farmers in Italy to identify and assess their interests and concerns regarding AC systems. Farmers appeared to be familiar with managing forest plantations as species mixtures and the value of fuelwood. However, the value of the timber and biomass produced during the rotation appeared to be farmers’ main source of uncertainty, with no clear idea of what demand there would be for both wood products, and they assigned a higher rank to the importance of environmental benefits (biodiversity, landscape, soil fertility improvement). This indicated that there was a need to study the economic performance of the AC system developing two tools: a simplified economic calculator for stakeholders, that can estimate and compare net present value (NPV) of different AC systems, and a more complex model, adapting FarmSAFE. Biophysical data was generated using LERSAFE. Wood chips from the SRC component were found to have a low market value, and AC profitability depends mostly on the timber trees, with the essential need to optimize revenue from the valuable timber, especially by maximizing its quality. Therefore, the SRC component has an important role to play in increasing the quality of the valuable timber by improving timber tree form, reducing the costs of management operations and for giving a revenue during the growth of standard trees. AC could be an innovative option for timber and bioenergy production, integrating some of the advantages that are characteristic of agroforestry systems into mixed tree plantations

Alley coppice: an innovative land use system - options of system design with experimental evidence

Agroforestry and Short Rotation Coppice (SRC), for timber and bioenergy wood production, are recognized as economically viable and sustainable as separate cropping systems under ideal growing conditions. Little is known about agricultural and ecological interactions which might occur combining them in a tree-based intercropping system. This mixed approach, called alley coppice, is currently investigated in an European research Project (www.agrocop.com), and has important advantages: (i) a regular income guaranteed from the SRC component; (ii) light competition between species can often improve the stem form of timber trees; (iii) timber trees can be planted at the final spacing, avoiding expensive thinning; (iv) SRC component protects young timber trees from wind/storm damage; (v) alley coppice is expected to have positive impacts on biodiversity, and reducing soil erosion. Three system designs are currently investigated: Simultaneous planting (SP); Lagged planting (LP) and Border planting (BP). In SP, timber and SRC components are planted in the same year; the key investigated factor is the distance between timber trees and the first SRC row, comparing 1, 2, 3 m in plantations in Ireland, Germany and Italy. A tree row width of three meters guaranteed satisfying growth rates of Sorbus and Pyrus timber trees in a mixture with 2-yr SRC poplar (Populus spp) in Italy, improving timber wood quality. LP, with planting SRC under adult timber trees, is studied in France and Ireland, according to timber tree age, species and inter-row spacings. In France, light and water competition had significant effects on poplar SRC growth and yield according to the distance from the walnut trees. BP involves planting timber trees along the borders of SRC blocks. Experimental plantations were established in Ireland and Germany, with the aim of avoiding asymmetric light competition that might hamper stem form of timber trees. Guidelines for practitioners on alley coppice optimization will be provided at the end of the project

Methodological review of NMA bias concepts provides groundwork for the development of a list of concepts for potential inclusion in a new risk of bias tool for network meta-analysis (RoB NMA Tool)

INTRODUCTION: Network meta-analyses (NMAs) have gained popularity and grown in number due to their ability to provide estimates of the comparative effectiveness of multiple treatments for the same condition. The aim of this study is to conduct a methodological review to compile a preliminary list of concepts related to bias in NMAs. METHODS AND ANALYSIS: We included papers that present items related to bias, reporting or methodological quality, papers assessing the quality of NMAs, or method papers. We searched MEDLINE, the Cochrane Library and unpublished literature (up to July 2020). We extracted items related to bias in NMAs. An item was excluded if it related to general systematic review quality or bias and was included in currently available tools such as ROBIS or AMSTAR 2. We reworded items, typically structured as questions, into concepts (i.e. general notions). RESULTS: One hundred eighty-one articles were assessed in full text and 58 were included. Of these articles, 12 were tools, checklists or journal standards; 13 were guidance documents for NMAs; 27 were studies related to bias or NMA methods; and 6 were papers assessing the quality of NMAs. These studies yielded 99 items of which the majority related to general systematic review quality and biases and were therefore excluded. The 22 items we included were reworded into concepts specific to bias in NMAs. CONCLUSIONS: A list of 22 concepts was included. This list is not intended to be used to assess biases in NMAs, but to inform the development of items to be included in our tool

Interventions for escalation of therapy for acute exacerbations of asthma in children: an overview of Cochrane Reviews

This is a protocol for a Cochrane Review (Overview). The objectives are as follows: Main objectives •To summarise Cochrane Reviews on the efficacy and safety of interventions for escalation of treatment for children with acute exacerbations of asthma Secondary objectives •To identify gaps in the current evidence base that will inform recommendations for future research and subsequent Cochrane Reviews •To categorise information on reported outcome measures used in trials of escalation of treatment for acute exacerbations of asthma in children, and to make recommendations for development and reporting of standard outcomes in future trials and reviews •To identify relevant research papers that have been published since the date of publication of each included revie

Selecting and implementing overview methods: implications from five exemplar overviews

This is the final version of the article. Available from BioMed Central via the DOI in this record.Background Overviews of systematic reviews are an increasingly popular method of evidence synthesis; there is a lack of clear guidance for completing overviews and a number of methodological challenges. At the UK Cochrane Symposium 2016, methodological challenges of five overviews were explored. Using data from these five overviews, practical implications to support methodological decision making of authors writing protocols for future overviews are proposed. Methods Methods, and their justification, from the five exemplar overviews were tabulated and compared with areas of debate identified within current literature. Key methodological challenges and implications for development of overview protocols were generated and synthesised into a list, discussed and refined until there was consensus. Results Methodological features of three Cochrane overviews, one overview of diagnostic test accuracy and one mixed methods overview have been summarised. Methods of selection of reviews and data extraction were similar. Either the AMSTAR or ROBIS tool was used to assess quality of included reviews. The GRADE approach was most commonly used to assess quality of evidence within the reviews. Eight key methodological challenges were identified from the exemplar overviews. There was good agreement between our findings and emerging areas of debate within a recent published synthesis. Implications for development of protocols for future overviews were identified. Conclusions Overviews are a relatively new methodological innovation, and there are currently substantial variations in the methodological approaches used within different overviews. There are considerable methodological challenges for which optimal solutions are not necessarily yet known. Lessons learnt from five exemplar overviews highlight a number of methodological decisions which may be beneficial to consider during the development of an overview protocol.The overview conducted by Pollock [19] was supported by a project grant from the Chief Scientist Office of the Scottish Government. The overview conducted by McClurg [21] was supported by a project grant by the Physiotherapy Research Foundation. The overview by Hunt [22] was supported as part of doctoral programme funding by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). The overview conducted by Estcourt [20] was supported by an NIHR Cochrane Programme Grant for the Safe and Appropriate Use of Blood Components. The overview conducted by Brunton [23] was commissioned by the Department of Health as part of an ongoing programme of work on health policy research synthesis. Alex Pollock is employed by the Nursing, Midwifery and Allied Health Professions (NMAHP) Research Unit, which is supported by the Chief Scientist Office of the Scottish Government. Pauline Campbell is supported by the Chief Nurses Office of the Scottish Government

Measured in-situ mass absorption spectra for nine forms of highly-absorbing carbonaceous aerosol

Mass absorption coefficient spectra were measured between λ = 500 nm and 840 nm for nine forms of highly-absorbing carbonaceous aerosol: five samples generated from gas-, liquid- and solid-fueled flames; spark-discharge fullerene soot; graphene and reduced graphene oxide (rGO) crumpled nanosheets; and fullerene (C_(60)) assemblies. Aerosol absorption spectra were measured for size- and mass-selected particles and found to be dependent on fuel type and formative conditions. Flame-generated particles had morphologies consistent with freshly emitted black carbon (BC) with mass absorption coefficients (MAC) ranging between 3.8 m^2 g^(−1) and 8.6 m^2 g^(−1) at λ = 550 nm. Absorption Ångström exponents (AAE) – i.e. MAC spectral dependence – ranged between 1.0 and 1.3 for flame-generated particles and up to 7.5 for C_(60). The dependence of MAC and AAE on mobility diameter and particle morphology was also investigated. Lastly, the current data were compared to all previously published MAC measurements of highly-absorbing carbonaceous aerosol

How can clinicians choose between conflicting and discordant systematic reviews? A replication study of the Jadad algorithm

Introduction: The exponential growth of published systematic reviews (SRs) presents challenges for decision makers seeking to answer clinical, public health or policy questions. In 1997, an algorithm was created by Jadad et al. to choose the best SR across multiple. Our study aims to replicate author assessments using the Jadad algorithm to determine: (i) if we chose the same SR as the authors; and (ii) if we reach the same results. Methods: We searched MEDLINE, Epistemonikos, and Cochrane Database of SRs. We included any study using the Jadad algorithm. We used consensus building strategies to operationalise the algorithm and to ensure a consistent approach to interpretation. Results: We identified 21 studies that used the Jadad algorithm to choose one or more SRs. In 62% (13/21) of cases, we were unable to replicate the Jadad assessment and ultimately chose a different SR than the authors. Overall, 18 out of the 21 (86%) independent Jadad assessments agreed in direction of the findings despite 13 having chosen a different SR. Conclusions: Our results suggest that the Jadad algorithm is not reproducible between users as there are no prescriptive instructions about how to operationalise the algorithm. In the absence of a validated algorithm, we recommend that healthcare providers, policy makers, patients and researchers address conflicts between review findings by choosing the SR(s) with meta-analysis of RCTs that most closely resemble their clinical, public health, or policy question, are the most recent, comprehensive (i.e. number of included RCTs), and at the lowest risk of bias

Methodological review of NMA bias concepts provides groundwork for the development of a list of concepts for potential inclusion in a new risk of bias tool for network meta-analysis (RoB NMA Tool)

INTRODUCTION: Network meta-analyses (NMAs) have gained popularity and grown in number due to their ability to provide estimates of the comparative effectiveness of multiple treatments for the same condition. The aim of this study is to conduct a methodological review to compile a preliminary list of concepts related to bias in NMAs. METHODS AND ANALYSIS: We included papers that present items related to bias, reporting or methodological quality, papers assessing the quality of NMAs, or method papers. We searched MEDLINE, the Cochrane Library and unpublished literature (up to July 2020). We extracted items related to bias in NMAs. An item was excluded if it related to general systematic review quality or bias and was included in currently available tools such as ROBIS or AMSTAR 2. We reworded items, typically structured as questions, into concepts (i.e. general notions). RESULTS: One hundred eighty-one articles were assessed in full text and 58 were included. Of these articles, 12 were tools, checklists or journal standards; 13 were guidance documents for NMAs; 27 were studies related to bias or NMA methods; and 6 were papers assessing the quality of NMAs. These studies yielded 99 items of which the majority related to general systematic review quality and biases and were therefore excluded. The 22 items we included were reworded into concepts specific to bias in NMAs. CONCLUSIONS: A list of 22 concepts was included. This list is not intended to be used to assess biases in NMAs, but to inform the development of items to be included in our tool