Sensory and instrumental analysis of medium and long shelf-life Charentais cantaloupe melons (Cucumis melo L.) harvested at different maturities

The flavour profiles of two genotypes of Charentais cantaloupe melons (medium shelf-life and long shelf-life), harvested at two distinct maturities (immature and mature fruit), were investigated. Dynamic headspace extraction (DHE), solid-phase extraction (SPE), gas chromatography–mass spectrometry (GC-MS) and gas chromatography–olfactometry/mass spectrometry (GC-O/MS) were used to determine volatile and semi-volatile compounds. Qualitative descriptive analysis (QDA) was used to assess the organoleptic impact of the different melons and the sensory data were correlated with the chemical analysis. There were significant, consistent and substantial differences between the mature and immature fruit for the medium shelf-life genotype, the less mature giving a green, cucumber character and lacking the sweet, fruity character of the mature fruit. However, maturity at harvest had a much smaller impact on the long shelf-life melons and fewer differences were detected. These long shelf-life melons tasted sweet, but lacked fruity flavours, instead exhibiting a musty, earthy character

Reconstructing communities in cluster trials?

BACKGROUND: There is growing interest in the ethics of cluster trials, but no literature on the uncertainties in defining communities in relation to the scientific notion of the cluster in collaborative biomedical research. METHODS: The views of participants in a community-based cluster randomised trial (CRT) in Mumbai, India, were solicited regarding their understanding and views on community. We conducted two focus group discussions with local residents and 20 semi-structured interviews with different respondent groups. On average, ten participants took part in each focus group, most of them women aged 18-55. We conducted semi-structured interviews with ten residents (nine women and one man) lasting approximately an hour each and seven individuals (five men and two women) identified by residents as local leaders or decision-makers. In addition, we interviewed two Municipal Corporators (locally elected government officials involved in urban planning and development) and one representative of a political party located in a slum community. RESULTS: Residents' sense of community largely matched the scientific notion of the cluster, defined by the investigators as a geographic area, but their perceived needs were not entirely met by the trial. CONCLUSION: We examined whether the possibility of a conceptual mismatch between 'clusters' and 'communities' is likely to have methodological implications for a study or to lead to potential social disharmony because of the research interventions, arguing that it is important to take social factors into account as well as statistical efficiency when choosing the size and type of clusters and designing a trial. One method of informing such a design would be to use existing forums for community engagement to explore individuals' primary sense of community or social group and, where possible, to fit clusters around them. TRIAL REGISTRATION: ISRCTN Register: ISRCTN56183183 Clinical Trials Registry of India: CTRI/2012/09/003004

Public involvement in the governance of population-level biomedical research: unresolved questions and future directions

Population-level biomedical research offers new opportunities to improve population health, but also raises new challenges to traditional systems of research governance and ethical oversight. Partly in response to these challenges, various models of public involvement in research are being introduced. Yet, the ways in which public involvement should meet governance challenges are not well understood. We conducted a qualitative study with 36 experts and stakeholders using the World Café method to identify key governance challenges and explore how public involvement can meet these challenges. This brief report discusses four cross-cutting themes from the study: the need to move beyond individual consent; issues in benefit and data sharing; the challenge of delineating and understanding publics; and the goal of clarifying justifications for public involvement. The report aims to provide a starting point for making sense of the relationship between public involvement and the governance of population-level biomedical research, showing connections, potential solutions and issues arising at their intersection. We suggest that, in population-level biomedical research, there is a pressing need for a shift away from conventional governance frameworks focused on the individual and towards a focus on collectives, as well as to foreground ethical issues around social justice and develop ways to address cultural diversity, value pluralism and competing stakeholder interests. There are many unresolved questions around how this shift could be realised, but these unresolved questions should form the basis for developing justificatory accounts and frameworks for suitable collective models of public involvement in population-level biomedical research governance. [Abstract copyright: © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.

Oxidative discolouration in whole-head and cut lettuce: biochemical and environmental influences on a complex phenotype and potential breeding strategies to improve shelf-life

Lettuce discolouration is a key post-harvest trait. The major enzyme controlling oxidative discolouration has long been considered to be polyphenol oxidase (PPO) however, levels of PPO and subsequent development of discolouration symptoms have not always correlated. The predominance of a latent state of the enzyme in plant tissues combined with substrate activation and contemporaneous suicide inactivation mechanisms are considered as potential explanations for this phenomenon. Leaf tissue physical properties have been associated with subsequent discolouration and these may be influenced by variation in nutrient availability, especially excess nitrogen and head maturity at harvest. Mild calcium and irrigation stress has also been associated with a reduction in subsequent discolouration, although excess irrigation has been linked to increased discolouration potentially through leaf physical properties. These environmental factors, including high temperature and UV light intensities, often have impacts on levels of phenolic compounds linking the environmental responses to the biochemistry of the PPO pathway. Breeding strategies targeting the PALand PPOpathway biochemistry and environmental response genes are discussed as a more cost-effective method of mitigating oxidative discolouration then either modified atmosphere packaging or post-harvest treatments, although current understanding of the biochemistry means that such programs are likely to be limited in nature and it is likely that they will need to be deployed alongside other methods for the foreseeable future

The Ethics of Community Effectiveness Research in Developing Countries

The aim of the thesis is to explore and discuss the distinct ethical issues raised by the conduct of health-related cluster randomised trials in developing countries, in particular those related to informed consent and representation. The thesis has four objectives: First, it seeks to identify ethical issues and their importance arising in CRTs and present how they are currently being addressed in published trial reports and papers on the ethics of CRTs. Second, it aims to discuss the limitations of addressing such ethical issues within the existing research ethics framework. Third, by relying on a human right to health, it aims to suggest a broader research ethics framework, beyond the existing clinical ethics paradigm, that takes into account the variety of health studies conducted in developing settings, as well as the broader socio-political context where collaborative health research takes place. Fourth, by examining the common moral features between cluster health studies and public health interventions, it aims to inform current research ethics guidelines and discussions on the ethics of cluster research by suggesting solutions to the problem of informed consent and cluster representation in developing countries, as well as to demonstrate the strength of the suggested research ethics framework in dealing with such complex issues. I argue that under specific conditions a cluster trial is morally legitimate to proceed despite the absence of informed consent and that a decision regarding the conduct of research should be within the responsibilities of the legitimate political authorities of the host country. I conclude that collaborative health research, which aims to improve the health status of a developing population, should be part of a country’s policy, similarly to decisions concerning the implementation of public health measures, and that human subjects should be protected at individual, social and institutional level

Children with medical complexities: their distinct vulnerability in health systems’ Covid-19 response and their claims of justice in the recovery phase

In this paper, we discuss the lack of consideration given to children in the COVID-19 health systems policy response to the pandemic. We do this by focusing on the case of children with complex medical needs. We argue that, in broad terms, health systems policies that were implemented during the pandemic failed adequately to meet our obligations to both children generally and those with complex medical needs by failing to consider those needs and so to give them fair protection against harm and disadvantage. We argue that justice requires that the distinct needs and vulnerabilities of children with medical complexities are explicitly integrated and prioritised in decisions concerning healthcare and operational planning in the recovery phase and beyond

The post-normal challenges of COVID-19: constructing effective and legitimate responses

The ongoing COVID-19 emergency clearly presents novel challenges, both in terms of difficulties for maintaining public health and in assuring that governmental responses are ethically sound. Centrally, responses must respect, as best as possible, fundamental human rights and human values. Conflicts among values arise in response to the crisis, and public officials have no choice but to prioritize some while sacrificing others. Utilizing the concepts of effectiveness and legitimacy within the framework of post-normal science (PNS), we investigate and recommend processes and measures to address COVID-19 that support increased public health, while upholding established rights and values. The effectiveness and legitimacy of science-led policymaking requires investigation of how that policy ought to be made (e.g. concepts of policymaking and PNS), as well as how it ought to interact with diversely-constituted publics (e.g. public inclusion in policymaking and policy communication)

Flavour profile of three novel acidic varieties of muskmelon (Cucumis melo L.)

Novel acidic varieties of muskmelon (Cucumis melo L.) are emerging onto the UK market. These melons contain almost twice the amount of citric acid compared to standard melons and are described as ‘zesty and fresh’. This study compared the flavour components of three acidic varieties with a standard Galia-type melon. The volatile and semivolatile compounds were extracted using dynamic headspace extraction (DHE) or solid-phase microextraction (SPME) and solid phase extraction (SPE) respectively, followed by gas chromatography – mass spectrometry (GC-MS) and gas chromatography – olfactometry (GC-O). More than 50 volatile and 50 semivolatile compounds were identified in the headspace and the SPE extracts respectively. GC-O revealed 15 odour-active components in the headspace, with esters being consistently higher in acidic variety. This study showed quantitative and qualitative differences between all four varieties and key differences between acidic varieties and standard melons

Quality characteristics of six Charentais cantaloupe genotypes during storage

The flavour profiles of six different genotypes of Charentais cantaloupe melons (medium and long shelf-life) were investigated at three different storage points (after harvest, ripe and overripe). Several physiological characteristics were also studied in order to investigate their role and their ability to discriminate the shelf-life of melon. Dynamic headspace extraction followed by GC-MS was used for the analysis of volatile compounds. Quantitative differences existed among the six genotypes and between the three storage points. Overall the aim of this study was to find a flavoursome long shelf-life genotype that would be able to deliver desirable quality attributes (appearance, aroma and texture

Elucidation of the biochemical pathways involved in two distinct cut-surface discolouration phenotypes of lettuce

To understand better the biochemistry and underlying genetic control of postharvest discolouration in lettuce, an F7 recombinant inbred population (Saladin x Iceberg) was grown in field trials and phenotyped. We identified two distinct discolouration phenotypes, pinking and browning, which were negatively correlated at the phenotypic level and located six QTL associated with pinking and five QTL associated with browning plus two QTL associated with total discolouration which could not be attributed to either type, on an improved genetic map. Candidate genes underlying QTL were investigated. Plants showing extremes of discolouration were also grown under controlled environment conditions. Lines showing extreme phenotypes from both environments were used for transcriptome profiling and differentially expressed transcripts associated with pinking and browning were identified. Involvement of the phenylpropanoid, flavonoid and terpenoid biosynthesis pathways were indicated in the development of discolouration, with the point of divergence for development of the different discolouration phenotypes localised to the phenylpropanoid pathway. Other biochemistry including amino acid metabolism was also implicated with environmental factors including temperature, water availability and physical stress indicated as potential contributory factors. Differential transcriptional control may be involved in regulating discolouration, potentially through stereochemical selection