A two-stage stochastic programming with recourse model for determining robust planting plans in horticulture

A two-stage stochastic programming with recourse model for the problem of determining optimal planting plans for a vegetable crop is presented in this paper. Uncertainty caused by factors such as weather on yields is a major influence on many systems arising in horticulture. Traditional linear programming models are generally unsatisfactory in dealing with the uncertainty and produce solutions that are considered to involve an unacceptable level of risk. The first stage of the model relates to finding a planting plan which is common to all scenarios and the second stage is concerned with deriving a harvesting schedule for each scenario. Solutions are obtained for a range of risk aversion factors that not only result in greater expected profit compared to the corresponding deterministic model, but also are more robust

Keeping adults physically active: intervention development and randomised controlled feasibility study

Introduction Physical inactivity contributes to disability and falls in community dwelling older adults. Regularly attending falls prevention exercise programmes improves health, physical function and reduces falling rates in older people. However, older adults rarely maintain moderate to vigorous physical activity (MVPA) beyond 12 months after exercise programmes end, which results in the beneficial health effects being lost. Research is needed to examine whether physical activity (PA) can be maintained in older adults exiting falls management exercise (FaME) programmes. Aim The aim of this PhD was to develop and investigate the feasibility of an intervention to maintain PA in community-dwelling adults aged 65 years and older exiting FaME programmes. This aim was achieved by the following research objectives: 1. To identify effective intervention strategies for maintaining PA in older adults by conducting a systematic review. 2. To use the findings of the systematic review alongside an intervention development tool and an expert steering group to design an intervention that aims to maintain PA in older adults who have attended a FaME programme. 3. To conduct a study to test the feasibility, acceptability and fidelity of delivering the PA maintenance intervention to a group of older adults exiting the FaME programme. To examine the acceptability of, and adherence to the intervention by the participants and Postural Stability Instructors (PSI). To estimate the study parameters needed for a future definitive trial. Methods Systematic review: Controlled studies assessing interventions for maintaining PA, in people aged 65 years and older, were identified from electronic bibliographic databases and hand searching. Two researchers independently assessed for eligibility, risk of bias and extracted data. Only studies assessing community dwelling older adults aged 65 years old and older were included. Study characteristics, behaviour change strategies, intervention features, delivery modes and PA outcomes were synthesised narratively. Intervention development: The Keeping Adults Physically Active (KAPA) intervention was developed using Bartholomew’s intervention mapping (IM) framework. The IM process involved creating intervention objectives by reviewing qualitative data on older adults’ PA determinants. Effective PA intervention strategies were identified in the systematic review and the National Institute of Clinical Excellence (NICE) guidelines for PA and behaviour change. The intervention strategies and programme design was built from the output of these initial stages. An expert steering group guided the design of the KAPA intervention and its implementation plan. KAPA Feasibility study: A feasibility study was conducted in 8 FaME classes (4 intervention and 4 control groups) between January 2017 and January 2018. The study design was a two-arm, cluster randomised, multi-site feasibility study comparing the KAPA intervention with usual care controls. A sample of 10 PSIs and 50 community-dwelling adults aged 65 years old or older were recruited. Quantitive and qualitative research methods were used to examine the KAPA intervention. Acceptability, feasibility, adherence and fidelity were assessed by: i) Estimating study recruitment, retention and attendance rates. ii) Examining acceptability by conducting semi-structured interviews with the participants in receipt of, and the PSIs delivering, the KAPA intervention. iii) Investigating adherence by: a) analysing the PSI’s completion rates of the class registers; b) examining class registers for the KAPA participants’ adherence with the PA diaries and goals. iv) Examining the fidelity of the KAPA intervention using class observations and PSI interviews. v) Investigating parameter estimates for a future definitive trial by: a) estimating the potential effect size in terms of MVPA, b) estimating the intraclass correlation coefficient (ICC) for MVPA. vi) Describing usual care by its intervention components. vii) Identifying the data collection tools needed to cost the intervention in a definitive trial. viii) Recording adverse events and assessing them for causality in relation to the delivery of the KAPA intervention. Results Systematic review: The search yielded 25,761 publications and 19 studies met the inclusion criteria. Of the 19 studies, 13 reported significantly maintaining PA. There was considerable heterogeneity between the studies and interventions delivered. Interventions delivered on a monthly, or quarterly basis over an intervention period of 6 months to 2 years most consistently maintained significant PA effects. Interventions were effective regardless of delivery mode, setting, intervention provider or whether delivered to groups or individuals. Providing pedometers, counselling and motivational interviewing helped to sustain PA. Most studies (n=17) were judged to be of an unclear or high risk of bias. Intervention development: The KAPA intervention comprised of six group sessions of motivational interviewing, delivered by a trained and mentor supported PSI. Participant manuals, illustrated exercise books and PA monitoring tools supported the KAPA intervention. KAPA sessions lasted between 60 to 90 minutes and were delivered in community-based venues over a 6-month duration. Participants unable to attend group sessions received the KAPA intervention via telephone. KAPA Feasibility study: Recruitment, retention and adherence rates: The aim of recruiting 120 participants was not achieved. Fifty of the sixty-seven participants (74.6%) invited into the study agreed to take part. Forty-five participants (92.3%) provided outcome data at the 6-month time point. Attendance rates to the KAPA intervention sessions were high as 94.2% of the total available sessions were attended. Acceptability: Delivering KAPA was acceptable from the perspective of the PSIs. KAPA participants often expressed positive views about the venues and PSIs and talked about gaining enjoyment from group interactions. Many discussed the writing activities to be the least enjoyable element of the KAPA intervention. PA engagement was reinforced by peer support. During the interviews the KAPA intervention participants discussed increasing their walking and home-based exercise activities. Participants believed the illustrated home exercise booklet and the PA monitoring tools helped them keep active. Adherence: Participant and PSI adherence with the KAPA intervention could not be assessed due to missing register data. Fidelity: Fidelity observations showed that 75% of the intervention components were delivered. Three intervention PSIs discussed adapting KAPA during the semi-structured interviews. Parameter estimates: The proportion of participants reporting at least 150 minutes of MVPA per week rose from 56.3% to 62.5% in the intervention arm and from 41.4% to 52.0% in the usual care arm (OR 1.25, 95% CI 0.26 to 5.88, p=0.78). The ICCs for reaching the target 150 minutes of MVPA weekly was 0.000 (95% CI 0.000 to 0.237). Usual care descriptive: Usual care was described as the continued provision of FaME as an exercise maintenance class. Data collection tool: Cost data relating to telephone usage was inaccurate. The current cost proforma needs adapting before its use in a definitive trial. Adverse events: Three adverse events, possibly relating to KAPAs delivery, were reported. Conclusion The systematic review suggested that PA maintenance programmes can help older adults stay active. The findings suggested that intervention time periods and contact frequency may influence effectiveness. The knowledge gained from the review, NICE guidelines and the expert steering group helped to develop the KAPA intervention. The KAPA intervention consisted of six-monthly group sessions of motivational interviewing, supported by written materials and self-monitoring tools. PSIs found the KAPA intervention feasible to deliver. Participants reported the illustrated home exercise booklet, peer support and the PA monitoring tools encouraged them to keep active. A definitive trial is needed to assess whether PA can be significantly maintained in response to the KAPA intervention

Life cycle modelling of environmental impacts of application of processed organic municipal solid waste on agricultural land (EASEWASTE)

A model capable of quantifying the potential environmental impacts of agricultural application of composted or anaerobically digested source-separated organic municipal solid waste (MSW) is presented. In addition to the direct impacts, the model accounts for savings by avoiding the production and use of commercial fertilizers. The model is part of a larger model, Environmental Assessment of Solid Waste Systems and Technology (EASEWASTE), developed as a decisionsupport model, focusing on assessment of alternative waste management options. The environmental impacts of the land application of processed organic waste are quantified by emission coefficients referring to the composition of the processed waste and related to specific crop rotation as well as soil type. The model contains several default parameters based on literature data, field experiments and modelling by the agro-ecosystem model, Daisy. All data can be modified by the user allowing application of the model to other situations. A case study including four scenarios was performed to illustrate the use of the model. One tonne of nitrogen in composted and anaerobically digested MSW was applied as fertilizer to loamy and sandy soil at a plant farm in western Denmark. Application of the processed organic waste mainly affected the environmental impact categories global warming (0.4–0.7 PE), acidification (–0.06 (saving)–1.6 PE), nutrient enrichment (–1.0 (saving)–3.1 PE), and toxicity. The main contributors to these categories were nitrous oxide formation (global warming), ammonia volatilization (acidification and nutrient enrichment), nitrate losses (nutrient enrichment and groundwater contamination), and heavy metal input to soil (toxicity potentials). The local agricultural conditions as well as the composition of the processed MSW showed large influence on the environmental impacts. A range of benefits, mainly related to improved soil quality from long-term application of the processed organic waste, could not be generally quantified with respect to the chosen life cycle assessment impact categories and were therefore not included in the model. These effects should be considered in conjunction with the results of the life cycle assessment

Exact Speedup Factors and Sub-Optimality for Non-Preemptive Scheduling

Fixed priority scheduling is used in many real-time systems; however, both preemptive and non-preemptive variants (FP-P and FP-NP) are known to be sub-optimal when compared to an optimal uniprocessor scheduling algorithm such as preemptive earliest deadline first (EDF-P). In this paper, we investigate the sub-optimality of fixed priority non-preemptive scheduling. Specifically, we derive the exact processor speed-up factor required to guarantee the feasibility under FP-NP (i.e. schedulability assuming an optimal priority assignment) of any task set that is feasible under EDF-P. As a consequence of this work, we also derive a lower bound on the sub-optimality of non-preemptive EDF (EDF-NP). As this lower bound matches a recently published upper bound for the same quantity, it closes the exact sub-optimality for EDF-NP. It is known that neither preemptive, nor non-preemptive fixed priority scheduling dominates the other, in other words, there are task sets that are feasible on a processor of unit speed under FP-P that are not feasible under FP-NP and vice-versa. Hence comparing these two algorithms, there are non-trivial speedup factors in both directions. We derive the exact speed-up factor required to guarantee the FP-NP feasibility of any FP-P feasible task set. Further, we derive the exact speed-up factor required to guarantee FP-P feasibility of any constrained-deadline FP-NP feasible task set

Presence of Locusta diuretic hormone in endocrine cells of the ampullae of locust Malpighian tubules

Distant viewBuilt 1120-124

Integrating Science and Policy Through Stakeholder-Engaged Scenarios

Scenario development for integrated analysis focuses on adopting an interdisciplinary approach covering key elements of the biophysical environment as well as changes in livelihoods, education, economics and governance both locally and internationally. Most importantly, the development of these scenarios generates a dialogue across institutions, stakeholders and sectors, with the use of common data and agreement on shared qualitative and quantitative futures. The scenarios adopted combine three alternative future climates and three socio-economic development pathways. Quantification of these issues included estimation based on published data, expert knowledge and stakeholder engagement, particularly where data are most uncertain or unknown. This chapter demonstrates this approach for coastal Bangladesh

New physiological activities of myosuppressin, sulfakinin and NVP-like peptide in Zophobas atratus beetle

Three neuropeptides Zopat-MS-2 (pEDVDHVFLRFa), Zopat-SK-1 (pETSDDYGHLRFa) and Zopat-NVPL-4trunc. (GRWGGFA), recently isolated from the neuroendocrine system of the Zophobas atratus beetle, were tested for their myotropic and hyperglycaemic activities in this species. These peptides exerted differentiated dose-dependent and tissue specific physiological effects. Zopat-MS-2 inhibited contractions of the isolated heart, ejaculatory duct, oviduct and hindgut of adult beetles and induced bimodal effects in the heart contractile activity of pupae in vivo. It also increased the haemolymph free sugar level in larvae of this species, apart from myotropic activity. Zopat-SK-1 showed myostimulatory action on the isolated hindgut of the adult beetles, but it decreased contractions of the heart, ejaculatory duct and oviduct. Injections of this peptide at a dose of 2 μg also caused delayed cardioinhibitory effects on the heartbeat of the pupae. Together with the ability to increase free sugar level in the haemolymph of larvae these were new physiological activities of sulfakinins in insects. Zopat-NVPL-4trunc. inhibited the muscle contractions of the two organs: hindgut and ejaculatory duct but it was inactive on the oviduct and the heart of the adult beetles. This peptide also increased free sugar level concentration in the haemolymph of Z. atratus larvae. These physiological actions are the first biological activities discovered for this group of the insect peptides. The present work showed pleiotropic activity of three neuropeptides and indicates that the visceral muscle contractions and the haemolymph sugar homeostasis in Z. atratus are regulated by complex mechanisms