Population genetic structure in European lobsters: implications for connectivity, diversity and hatchery stocking

The European lobster Homarus gammarus is a marine crustacean prized for seafood, but populations across its range are threatened by fishery overexploitation. The species’ larval stages are planktonic, suggesting considerable dispersal among populations. The potential threats of overexploitation and erosion of population structure due to hatchery releases or inadvertent introductions make it important to understand the genetic structuring of populations across multiple geographic scales. Here we assess lobster population structure at a fine scale in Cornwall, southwestern UK, where a hatchery-stocking operation introduces cultured individuals into the wild stock, and at a broader European level, in order to compare the spatial scale of hatchery releases with that of population connectivity. Microsatellite genotypes of 24 individuals from each of 13 locations in Cornwall showed no fine-scale population structure across distances of up to ~230 km. Significant differentiation and isolation by distance were detected at a broader scale, using 300 additional individuals comprising a further 15 European samples. Signals of genetic heterogeneity were evident between an Atlantic cluster and samples from Sweden. Connectivity within the Atlantic and Swedish clusters was high, although evidence for isolation by distance and a transitional zone within the eastern North Sea suggested that direct gene exchange between these stocks is limited and fits a stepping-stone model. We conclude that hatchery-reared lobsters should not be released where broodstock are distantly sourced but, using Cornwall as a case study, microsatellites revealed no evidence that the normal release of hatchery stock exceeds the geographic scale of natural connectivity.European Social FundWorshipful Company of FishmongersBBSRCThis research was supported by Lobster Grower 2, a 3 yr project funded by Innovate-UK (TS/ N006097/1) and BBSRC (BB/N013891/1) under an AgriTech Catalyst Industrial Stage Award. We are also greatly appreciative of the studentship funding provided by the European Social Fund and of the grant awarded by the Fishmonger’s Company, UK, both of which made the work possible

Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

Introduction: The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. Methods: In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. Findings: Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. Interpretation: After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification

Spatial and temporal axes impact ecology of the gut microbiome in juvenile European lobster (Homarus gammarus)

Microbial communities within the gut can markedly impact host health and fitness. To what extent environmental influences affect the differential distribution of these microbial populations may therefore significantly impact the successful farming of the host. Using a sea-based container culture (SBCC) system for the on-growing of European lobster (Homarus gammarus), we tracked the bacterial gut microbiota over a 1-year period. We compared these communities with lobsters of the same cohort, retained in a land-based culture (LBC) system to assess the effects of the culture environment on gut bacterial assemblage and describe the phylogenetic structure of the microbiota to compare deterministic and stochastic assembly across both environments. Bacterial gut communities from SBCCs were generally more phylogenetically clustered, and therefore deterministically assembled, compared to those reared in land-based systems. Lobsters in SBCCs displayed significantly more species-rich and species-diverse gut microbiota compared to those retained in LBC. A reduction in the bacterial diversity of the gut was also associated with higher infection prevalence of the enteric viral pathogen Homarus gammarus nudivirus (HgNV). SBCCs may therefore benefit the overall health of the host by promoting the assembly of a more diverse gut bacterial community and reducing the susceptibility to disease.publishedVersio

European lobster Homarus gammarus aquaculture: Technical developments, opportunities and requirements

The European lobster (Homarus gammarus) has been the subject of aquaculture and related research efforts for the last 150 years, due to both the wild fishery and cultural value of the species. Since the middle of the 20th century, increasing anthropogenic pressure has led to a severe decline in wild fish and shellfish stocks, including H. gammarus, with some fisheries yet to recover. H. gammarus is amongst the most exclusive and valuable European shellfish products, and whilst management measures have been implemented to safeguard stocks, H. gammarus aquaculture is an increasingly credible approach to help to secure a sustainable lobster supply. Historically, this has been achieved by relatively small-scale release of hatchery-reared juveniles during stock enhancement programmes. Until recently, commercial attempts at farming have not been viable, mainly due to cost-prohibitive technical challenges. At present, there are several promising approaches to overcome bottlenecks hampering commercialisation of lobster aquaculture. This review summarises new technical and husbandryinnovations in H. gammarus culture since the start of the 21st century, including technological innovations, husbandry and expansion of the stock enhancement (release) and farming (production) sectors. Additionally, likely directions for both sectors in the coming decades are summarised, knowledge gaps identified and the societal support required to achieve further potential are discussed

Parent engagement and attendance in PEACH™ QLD – an up-scaled parent-led childhood obesity program

Abstract Background Parenting, Eating and Activity for Child Health (PEACH™) is a multicomponent treatment program delivered over ten group sessions to parents of overweight/obese primary school-aged children. It has been shown to be efficacious in an RCT and was recently translated to a large-scale community intervention funded by the Queensland (Australia) Government. Engagement (enrolment and attendance) was critical to achieving program outcomes and was challenging. The purpose of the present study was to examine sample characteristics and mediating factors that potentially influenced program attendance. Methods Data collected from parents who attended at least one PEACH™ Queensland session delivered between October 2013 and October 2015 (47 programs implemented in 29 discrete sites), was used in preliminary descriptive analyses of sample characteristics and multilevel single linear regression analyses. Mediation analysis examined associations between socio-demographic and parent characteristics and attendance at group sessions and potential mediation by child and parent factors. Results 365/467 (78%) enrolled families (92% mothers) including 411/519 (79%) children (55% girls, mean age 9 ± 2 years) attended at least one session (mean 5.6 ± 3.2). A majority of families (69%) self-referred to the program. Program attendance was greater in: advantaged (5.9 ± 3.1 sessions) vs disadvantaged families (5.4 ± 3.4 sessions) (p < 0.05); partnered (6.1 ± 3.1 sessions) vs un-partnered parents (5.0 ± 3.1 sessions) (p < 0.01); higher educated (6.1 ± 3.0 sessions) vs lower educated parents (5.1 ± 3.3 sessions) (p = 0.02); and self-referral (6.1 ± 3.1) vs professional referral (4.7 ± 3.3) (p < 0.001). Child (age, gender, pre-program healthy eating) and parent (perceptions of child weight, self-efficacy) factors did not mediate these relationships. Conclusions To promote reach and effectiveness of up-scaled programs, it is important to identify ways to engage less advantaged families who carry higher child obesity risk. Understanding differences in referral source and parent readiness for change may assist in tailoring program content. The influence of program-level factors (e.g. facilitator and setting characteristics) should be investigated as possible alternative mediators to program engagement

A narrative account of implementation lessons learnt from the dissemination of an up-scaled state-wide child obesity management program in Australia: PEACH™ (Parenting, Eating and Activity for Child Health) Queensland

Abstract Background PEACH™QLD translated the PEACH™ Program, designed to manage overweight/obesity in primary school-aged children, from efficacious RCT and small scale community trial to a larger state-wide program. This paper describes the lessons learnt when upscaling to universal health coverage. Methods The 6-month, family-focussed program was delivered in Queensland, Australia from 2013 to 2016. Its implementation was planned by researchers who developed the program and conducted the RCT, and experienced project managers and practitioners across the health continuum. The intervention targeted parents as the agents of change and was delivered via parent-only group sessions. Concurrently, children attended fun, non-competitive activity sessions. Sessions were delivered by facilitators who received standardised training and were employed by a range of service providers. Participants were referred by health professionals or self-referred in response to extensive promotion and marketing. A pilot phase and a quality improvement framework were planned to respond to emerging challenges. Results Implementation challenges included engagement of the health system; participant recruitment; and engagement. A total of 1513 children (1216 families) enrolled, with 1122 children (919 families) in the face-to-face program (105 groups in 50 unique venues) and 391 children (297 families) in PEACH™ Online. Self-referral generated 68% of enrolments. Unexpected, concurrent and, far-reaching public health system changes contributed to poor program uptake by the sector (only 56 [53%] groups delivered by publicly-funded health organisations) requiring substantial modification of the original implementation plan. Process evaluation during the pilot phase and an ongoing quality improvement framework informed program adaptations that included changing from fortnightly to weekly sessions aligned with school terms, revision of parent materials, modification of eligibility criteria to include healthy weight children and provision of services privately. Comparisons between pilot versus state-wide waves showed comparable prevalence of families not attending any sessions (25% vs 28%) but improved number of sessions attended (median = 5 vs 7) and completion rates (43% vs 56%). Conclusions Translating programs developed in the research context to enable implementation at scale is complex and presents substantial challenges. Planning must ensure there is flexibility to accommodate and proactively manage the system changes that are inevitable over time. Trial registration ACTRN12617000315314. This trial was registered retrospectively on 28 February, 2017

Impact of Side Chain Extension on the Morphology and Electrochemistry of Phosphonated Poly(Ethylenedioxythiophene) Derivatives

One factor with great bearing on the electrochemical performance of conjugated polymers is the film morphology. A balance between crystalline and amorphous domains needs to be achieved for the polymer to have an optimal ionic-electronic conductance. Here, the morphological and electrochemical properties of poly(ethylenedioxythiophene) polymers functionalized with phosphonate groups separated by methylene and butylene alkyl spacers from the backbone are compared. Extending the spacer from methylene to butylene increases structural ordering in the solid state as revealed by grazing-incidence wide-angle X-ray scattering. However, the ordered domains are only short range, suggestive of a paracrystalline morphology in which ordered regions are separated by amorphous regions. This has a negative impact on the intermolecular charge transport. The longer spacer appears to have impeded the uptake of hydrated counterions, seen by the increase in the ionization potential and energy requirement for electrochemical switching, as well as the decrease in the volumetric capacitance. These results elucidate the advantages of having the phosphonate pendant group close to the backbone, separated only by a methylene spacer. This synthetic design likely facilitates hydrated counterions to accumulate around the polar phosphonate groups, close to the doped backbone where they can easily compensate the charge carriers formed upon oxidation