197 research outputs found

    Characterising current agroecological and regenerative farming research capability and infrastructure, and examining the case for a Living Lab network [Final report]

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    Agriculture is a major cause of greenhouse gas (GHG) emissions, biodiversity loss, and pollution. Agroecological and regenerative farming have been advocated as alternative approaches that may have fewer negative (or even net positive) environmental impacts than conventional agriculture at farm- and landscape-scales, leading to considerable interest in these approaches (Newton et al. 2020; Bohan et al. 2022; Prost et al. 2023). This report forms the third part of a Defra-funded project Evaluating the productivity, environmental sustainability and wider impacts of agroecological and regenerative farming systems compared to conventional systems. The first part of this project was a rapid evidence review of agroecological and regenerative farming systems and their impacts (Burgess et al. 2023), and the second reported interview findings to examine farmer and stakeholder perspectives on barriers and enablers in agroecological and regenerative farming (Hurley et al. 2023). This third part of the project characterised the current research capability in agroecology and regenerative farming, and explored the potential role of a new ‘living lab’ trial network. Three objectives are addressed in this report: 1) Characterise the existing agroecological and regenerative farming research capability and infrastructure in the UK. 2) Explore lessons from recent research initiatives and identify key research gaps, to inform a potential UK living labs trials network in agroecology/regenerative farming. 3) Develop recommendations for a new living lab trial or research network in agroecology/regenerative farming. Objective 1 was addressed through an online survey to gather quantitative and qualitative data on current research initiatives and networks in regenerative farming and agroecology. There were 22 respondents from 20 organisations (Section 2.2). Key findings from the survey: • The size and the timescales of research initiatives varied substantially from single sites to networks of 50-100 sites and with agroecological/regenerative practices applied from one to over 20 years. • All the survey respondents applied multiple agroecological/regenerative processes and had multiple target outcomes. • Just under 40% of respondents are not currently collecting data from their network. • Three-quarters of the survey participants not currently collecting data stated they would like to collect data, given more funding, knowledge or support. • Biodiversity was one of the most frequent target outcomes, and data collection most frequently focussed on biodiversity. • Face-to-face and email communication was most frequently used between farms in a network. Around two-thirds of respondents also held farm demonstration days as a means of knowledge exchange. • Most of the research initiatives and networks were funded by charities, NGOs or funded themselves, with a smaller number funded by UK or EU government funding. • Growing to incorporate more farms and researchers and developing knowledge exchange further were prioritised as future aspirations by survey respondents. Incorporating more researchers and applying for funding were also a focus for many research initiatives. • Targeted funding was seen as very important in achieving future aspirations by most respondents, along with improved connections with farmers and landowners and improved skills and information for knowledge exchange. Improved infrastructure and monitoring tools were emphasised less, but still considered important. The online survey results illustrate the wide range of current research initiatives in agroecology and regenerative farming, which vary from small-scale trials on a few farms to robust, repeatable data collection across a large network. To illustrate the range of approaches in more details, five case studies were described (Section 2.3) which included an ongoing living lab network, three research project and a long-term demonstration farm. Key characteristics of eight European living labs were also summarised through a network of EU agroecology living labs (the ALL-Ready project; Section 2.4). Objective 2 was addressed through an online workshop, at which participants responded to questions about research gaps and priorities, infrastructure needs, and the barriers and enablers to data sharing and access (Section 3). Participants views were gathered through online discussion boards and facilitated verbal discussion (Figure 1). Key themes and conclusions from the workshop: • Many of the impacts of agroecology and regenerative practices remain poorly understood, with biodiversity and greenhouse gas emissions highlighted. • Impacts on multiple potential benefits and trade-offs (e.g. yield vs. biodiversity vs. greenhouse gas emissions) need to be understood. The variation in responses (e.g. between soil types or regions) was seen as a priority area for research to improve the understanding of scaling-up. • Research needs to be conducted at adequate temporal and spatial scales given the timescales needed for impacts of these practices to become apparent. • There may be a bias in farmer participation in agroecological and regenerative agriculture research (those who can afford the time and money). • Understanding transitions to agroecology and regenerative farming across different types of farm business was raised as a research gap along with investigating the role of knowledge in these types of practice. This was reflected in the discussion of infrastructure and skills, with support (better guidance, input from advisors) and upskilling/improvements in education seen as priorities to support transitions. • The role of economic drivers, including subsidies and supply chain structures, is a research priority to understand why and how farmers may transition to these farming practices. • Standardised assessments and monitoring tools (including farmer apps) were highlighted to support future research, in particular standardised soil carbon assessments. Hubs to loan monitoring equipment to farmers were also suggested. • The time commitment needed was seen as an impediment to data collection by farmers, with comments that research initiatives worked better with someone external collecting data. • Data quality and formats were raised as barriers to data sharing in agroecology/regenerative farming. Formats that can be easily read across a range of software were suggested as a solution, along with more standardised approaches in data collection. • Integration and sharing of data across platforms were another solution, in particular for regulatory data (e.g. pesticide usage). • A potential tension was raised between standardising monitoring approaches and data collection, and constraining innovation by farmers. • Our understanding of how widespread agroecological and regenerative farming practices are, and which are being used / in what combinations, is constrained by lack of uptake data. Practices are being implemented with or without subsidies, and in varying combinations with more conventional approaches. Without these uptake data, larger scale research and modelling may be constrained. The online survey findings, case studies and lessons learnt from the workshop participants informed the development of recommendations for a future living labs network in the UK (Objective 3, Section 4). Four options were proposed: i) Develop a standardised methodology or protocol for each of the 12 attributes listed for assessment within the Global Farm Metric, to support consistency of farm measurements. ii) New research projects funded to collect standardised data on impacts and trade-offs across existing networks of farms applying agroecological / regenerative practices. This would maximise research synergies with existing networks. iii) New research network set up to apply agroecological / regenerative practices on commercial farms, co-designed between farmers and researchers. Standardised data collection on impacts and trade-offs. iv) Long-term living lab UK network set up, within which facilitation roles and research projects funded. These options could be applied in combination (e.g. a standardised methodology (i) developed within (iv) a long-term living lab network ). Which options are taken forward will depend on funding and factors such as the structure of available funding and timescales. Indicative costs were provided for field surveys of greenhouse gases and biodiversity, two of the impacts identified as research priorities in the workshop

    The effect of multiple deformations on the formation of ultrafine grained steels

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    A C-Mn-Nb-Ti steel was deformed by hot torsion to study ultrafine ferrite formation through dynamic strain-induced transformation (DSIT) in conjunction with air cooling. A systematic study was carried out first to evaluate the effect of deformation temperature and prior austenite grain size on the critical strain for ultrafine ferrite formation (&epsilon; C,UFF) through single-pass deformation. Then, multiple deformations in the nonrecrystallization region were used to study the effect of thermomechanical parameters (i.e., strain, deformation temperature, etc.) on &epsilon; C,UFF. The multiple deformations in the nonrecrystallization region significantly reduced &epsilon; C,UFF, although the total equivalent strain for a given thermomechanical condition was higher than that required in single-pass deformation. The current study on a Ni-30Fe austenitic model alloy revealed that laminar microband structures were the key intragranular defects in the austenite for nucleation of ferrite during the hot torsion test. The microbands were refined and overall misorientation angle distribution increased with a decrease in the deformation temperature for a given thermomechanical processing condition. For nonisothermal multipass deformation, there was some contribution to the formation of high-angle microband boundaries from strains at higher temperature, although the strains were not completely additive.<br /

    Bond graph modelling of chemoelectrical energy transduction

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    Energy-based bond graph modelling of biomolecular systems is extended to include chemoelectrical transduction thus enabling integrated thermodynamically-compliant modelling of chemoelectrical systems in general and excitable membranes in particular. Our general approach is illustrated by recreating a well-known model of an excitable membrane. This model is used to investigate the energy consumed during a membrane action potential thus contributing to the current debate on the trade-off between the speed of an action potential event and energy consumption. The influx of Na+ is often taken as a proxy for energy consumption; in contrast, this paper presents an energy based model of action potentials. As the energy based approach avoids the assumptions underlying the proxy approach it can be directly used to compute energy consumption in both healthy and diseased neurons. These results are illustrated by comparing the energy consumption of healthy and degenerative retinal ganglion cells using both simulated and in vitro data

    Study protocol; thyroid hormone replacement for untreated older adults with subclinical hypothyroidism - a randomised placebo controlled trial (TRUST)

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    Background: Subclinical hypothyroidism (SCH) is a common condition in elderly people, defined as elevated serum thyroid-stimulating hormone (TSH) with normal circulating free thyroxine (fT4). Evidence is lacking about the effect of thyroid hormone treatment. We describe the protocol of a large randomised controlled trial (RCT) of Levothyroxine treatment for SCH. Methods: Participants are community-dwelling subjects aged ≥65 years with SCH, diagnosed by elevated TSH levels (≥4.6 and ≤19.9 mU/L) on a minimum of two measures ≥ three months apart, with fT4 levels within laboratory reference range. The study is a randomised double-blind placebo-controlled parallel group trial, starting with levothyroxine 50 micrograms daily (25 micrograms in subjects &lt;50Kg body weight or known coronary heart disease) with titration of dose in the active treatment group according to TSH level, and a mock titration in the placebo group. The primary outcomes are changes in two domains (hypothyroid symptoms and fatigue / vitality) on the thyroid-related quality of life questionnaire (ThyPRO) at one year. The study has 80% power (at p = 0.025, 2-tailed) to detect a change with levothyroxine treatment of 3.0% on the hypothyroid scale and 4.1% on the fatigue / vitality scale with a total target sample size of 750 patients. Secondary outcomes include general health-related quality of life (EuroQol), fatal and non-fatal cardiovascular events, handgrip strength, executive cognitive function (Letter Digit Coding Test), basic and instrumental activities of daily living, haemoglobin, blood pressure, weight, body mass index and waist circumference. Patients are monitored for specific adverse events of interest including incident atrial fibrillation, heart failure and bone fracture. Discussion: This large multicentre RCT of levothyroxine treatment of subclinical hypothyroidism is powered to detect clinically relevant change in symptoms / quality of life and is likely to be highly influential in guiding treatment of this common condition. Trial registration: Clinicaltrials.gov NCT01660126; registered 8th June 2012

    Evaluating the productivity, environmental sustainability and wider impacts of agroecological compared to conventional farming systems [Evidence project final report]

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    •Context, aim and objectives: Existing agriculture systems in the UK are effective at producing safe and relatively cheap food, but they are a cause of greenhouse gas emissions, biodiversity loss, and soil degradation. It has been proposed that greater use of agroecological and regenerative farming would lead to more positive effects. The aim of this project was to evaluate the productivity, environmental sustainability and wider impacts of agroecological compared to conventional farming, by addressing three objectives: 1. to undertake an evidence review of regenerative/agroecological farming systems, 2. to assess the risks, barriers and opportunities, and identifying gaps in the knowledge, and 3. to characterise agroecological farming research capability in the UK, explore gaps and priorities, and explore the potential role of a new “living lab” trial network. •The research has been presented in three separate reports (Burgess et al. 2023, Hurley et al. 2023, and Staley et al. 2023), which are attached as appendices. The main results are summarised here. •Method: Objective 1 was addressed using a desk-based rapid evidence review, and the level of confidence in the analysis was determined using the IPBES four-box model (IPBES 2017, 2018). Objective 2 was addressed by in-depth semi-structured interviews with 23 respondents including farmers in late 2022. The interviews were used to explore definitions of agroecological and regenerative farming, barriers to the adoption, and views towards the concept of ‘living labs’. Objective 3 was addressed through an online survey with 22 respondents from 20 organisations in January and February 2023, an online workshop with 34 participants in January 2023, and informed by the findings of work to address Objectives 1 and 2. •Results and discussion: 1.1 Defining and characterising agroecological farming systems. A review of definitions highlighted, in brief, that organic farming places strong restrictions on inputs, agroecological analyses often focus on principles, and regenerative farming typically emphasises the enhancement of soil health and biodiversity at a farm scale. The stakeholder interviews demonstrated that the terms regenerative agriculture and agroecology are employed interchangeably by some, sequentially by others (with regenerative practices seen as steps towards a bigger whole-farm agroecological system), and viewed by some as discrete (who recognise the social justice, economic and political aspects of agroecology). Within these different interpretations, regenerative practices are often assumed to be those that minimise tillage and bare soil, foster plant diversity, and reduce the use of pesticides and synthetic fertilizers. We noted that the impact of organic, agroecological or regenerative systems on greenhouse gas emissions was implicit rather than explicit. We identified 16 agroecological practices that could be used in the UK: crop rotations, conservation agriculture, cover crops, organic crop production, integrated pest management, the integration of livestock to crop systems, the integration of crops to livestock systems, field margin practices, pasture-fed livestock, multi-paddock grazing, organic livestock systems, tree crops, tree-intercropping, multistrata agroforestry and permaculture, silvopasture, and rewilding. 1.2. Impact of agroecological practices at farm-scale Our detailed review (see Burgess et al. 2023) highlighted that the 16 agroecological practices tended to increase soil and biomass carbon and biodiversity at a field- or farm scale relative to a stated baseline. The soil carbon benefits were due to increased crop cover, the introduction of grass into arable systems, reduced cultivation, and/or the addition of soil amendments. The biodiversity benefits were derived from an increased diversity of crops and habitats, introducing plants that attract pollinators, reduced grazing pressure, and/or reduced use of pesticides and herbicides. Gaps in knowledge were highlighted particularly in terms of greenhouse gas emissions and biodiversity. The analysed effect on yields, product values, and input costs varied according to the practice and the baseline comparison. Hence in most cases, a farmer will need to balance trade-offs, perhaps guided by tools such as financial, economic, or life cycle analyses. In some cases, such as organic farming, a reduction in profitability due to a reduction in yield and certification costs may be compensated by an increase in product price. 1.3 Modelling agroecological systems in a UK context Our review highlighted existing modelling frameworks such as ASSET, ERAMMP IMP, EVAST and NEVO that could be repurposed to model agroecological systems across the UK. However we identified three barriers to their successful use. Firstly, modellers need to quantify the links between agroecological scenarios, spatial contexts and selected parameters within the underlying models. Secondly, the lack of readily available experimental data on the effect of agroecological practices and their change over time means that parameterising models remains challenging, and the alternative use of expert-based scoring or benefits transfer approaches can result in very large levels of uncertainty. Thirdly, a validated assessment of the aggregated impact of agroecological practices at a national scale will require effective national monitoring approaches that can assess the level of implementation of agroecological practices. 2. Opportunities from and barriers to a transition to agroecological systems: The uptake of agroecological practices by farm businesses depends on the balance between the opportunities offered and the barriers to implementation. As indicated in 1.2, the opportunities include increased biomass carbon, increased soil carbon in surface layers, and increased on-farm biodiversity. Supermarkets could support environmentally-positive practices, but there is also a strong drive for low food prices. The barriers to some agroecological practices will be geographical or incompatibility with management objectives at the farm-level. However, where these are not constraints, the major barriers are often related to uncertainty in the effect of the practices on yields and costs, and the need to finance the initial investment and certification costs. Enablers to overcome those barriers include knowledge exchange (particularly as the promotion of agroecological practices is not driven by organisations wanting to sell a product) and financial incentives (with a focus on market mechanisms that differentiate between desired and undesired societal outcomes). Evidence from other countries, particularly France, show that agroecological transitions can succeed where the right combination of policy instruments (e.g. grants, support for advice and collaboration, cultural support) are sustained by long-term political will. 3.1 Existing agroecological farming research capability and infrastructure in the UK: The online survey results indicate that most agroecological farming research initiatives and networks were funded by charities, NGOs, or funded by themselves, with some receiving UK or EU government funding. The initiatives ranged from single sites to networks of 50-100 sites, and with agroecological practices applied from one to over 20 years. Farmer participation in such research may be biased to those who can afford the time and money. Five case studies are examined in the main report (Staley et al. 2023) including an ongoing living lab network, three research projects, and a long-term demonstration farm. Only about 60% of respondents were collecting data from their network, often focused on biodiversity. About three-quarters of those not collecting data, would collect data given more funding, knowledge, or support. Face-to-face and email communication was most frequently used between farms in a network. Around two-thirds of respondents held farm demonstration days as a means of knowledge exchange, and further knowledge exchange was a common future aspiration. 3.2 Research gaps and priorities: The survey and workshop supported the observation from 1.2 that many of the impacts of agroecology practices, especially in relation to greenhouse gas emissions and biodiversity, remain poorly understood. Although 1.2 focused on farm-level effects, the consequential effects of, for example, reduced yields with agroecological practices remains a pertinent area for research. The variation in responses between soil types or regions would also be useful to improve the understanding of scaling-up opportunities. The need to support research over a sustained time period was also highlighted as several years are often needed for effects to become apparent. The transition to agroecological farming across different types of business requires the need for farmer support and changes in agricultural education. The role of economic drivers and supply chain structures in supporting agroecological practices also requires more research. Standardisation of data quality and formats, in particular for regulatory data, could help reduce some barriers, but it could also constrain innovation. National assessments of agroecological practices are also constrained by a lack of uptake data. 3.3 Informing a potential UK living labs trial network Living labs have been defined as “user-centred, open innovation ecosystems based on a systematic user co-creation approach, integrating research and innovation processes in real life communities and settings” (Malmberg et al. 2017). Important roles for a living labs network include providing robust locally-relevant evidence of the productivity and financial viability of agroecological farming, improving data standardisation, and encouraging collaboration between farmers, organisations, and researchers for data collection, sharing, and use. The role of Defra in a living labs network should be negotiated carefully with existing stakeholders involved in agroecological/regenerative transitions. Such a network should be sufficiently resourced in order to fund research and knowledge exchange and in order to build capacity among farmers and organisational stakeholders. Building on the response of the survey, case studies, and workshops, the benefits and disadvantages of four options were examined: 1) Develop a standardised methodology or protocol to support consistency of farm measurements. Soil carbon and farm carbon accounting were particularly highlighted. 2) To maximise synergies within existing agroecological farm networks with standardised data collection. 3) A new research network set up to apply agroecological practices on commercial farms, co-designed between farmers and researchers, with standardised data collection on impacts and trade-offs. 4) A long-term living lab UK network set up, with funded facilitation roles and research projects. Some of the above options could be applied in combination. The optimal option will depend on the ambition of Defra and the available funding and timescales

    Murchison Widefield Array rapid-response observations of the short GRB 180805A

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    Abstract Here we present stringent low-frequency (185 MHz) limits on coherent radio emission associated with a short-duration gamma-ray burst (SGRB). Our observations of the short gamma-ray burst (GRB) 180805A were taken with the upgraded Murchison Widefield Array (MWA) rapid-response system, which triggered within 20s of receiving the transient alert from the Swift Burst Alert Telescope, corresponding to 83.7 s post-burst. The SGRB was observed for a total of 30 min, resulting in a 3σ3\sigma persistent flux density upper limit of 40.2 mJy beam–1. Transient searches were conducted at the Swift position of this GRB on 0.5 s, 5 s, 30 s and 2 min timescales, resulting in 3σ3\sigma limits of 570–1 830, 270–630, 200–420, and 100–200 mJy beam–1, respectively. We also performed a dedispersion search for prompt signals at the position of the SGRB with a temporal and spectral resolution of 0.5 s and 1.28 MHz, respectively, resulting in a 6σ6\sigma fluence upper-limit range from 570 Jy ms at DM =3 000=3\,000 pc cm–3 ( z∼2.5z\sim 2.5 ) to 1 750 Jy ms at DM =200=200 pc cm–3 ( z∼0.1)z\sim 0.1) , corresponding to the known redshift range of SGRBs. We compare the fluence prompt emission limit and the persistent upper limit to SGRB coherent emission models assuming the merger resulted in a stable magnetar remnant. Our observations were not sensitive enough to detect prompt emission associated with the alignment of magnetic fields of a binary neutron star just prior to the merger, from the interaction between the relativistic jet and the interstellar medium (ISM) or persistent pulsar-like emission from the spin-down of the magnetar. However, in the case of a more powerful SGRB (a gamma-ray fluence an order of magnitude higher than GRB 180805A and/or a brighter X-ray counterpart), our MWA observations may be sensitive enough to detect coherent radio emission from the jet-ISM interaction and/or the magnetar remnant. Finally, we demonstrate that of all current low- frequency radio telescopes, only the MWA has the sensitivity and response times capable of probing prompt emission models associated with the initial SGRB merger event.</jats:p
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