81 research outputs found
Assessing the sensitivity of seagrass bed biotopes to pressures associated with marine activities.
This project was commissioned to generate an improved understanding of the sensitivities of
seagrass habitats to pressures associated with human activities in the marine environment -
to provide an evidence base to facilitate and support management advice for Marine
Protected Areas; development of UK marine monitoring and assessment, and conservation
advice to offshore marine industries.
Seagrass bed habitats are identified as a Priority Marine Feature (PMF) under the Marine
(Scotland) Act 2010, they are also included on the OSPAR list of threatened and declining
species and habitats, and are a Habitat of Principle Importance (HPI) under the Natural
Environment and Rural Communities (NERC) Act 2006, in England and Wales.
The purpose of this project was to produce sensitivity assessments with supporting evidence
for the HPI, OSPAR and PMF seagrass/Zostera bed habitat definitions, clearly documenting
the evidence behind the assessments and any differences between assessments.
Nineteen pressures, falling in five categories - biological, hydrological, physical damage,
physical loss, and pollution and other chemical changes - were assessed in this report.
Assessments were based on the three British seagrasses Zostera marina, Z. noltei and
Ruppia maritima. Z. marina var. angustifolia was considered to be a subspecies of Z.
marina but it was specified where studies had considered it as a species in its own rights.
Where possible other components of the community were investigated but the basis of the
assessment focused on seagrass species.
To develop each sensitivity assessment, the resistance and resilience of the key elements
were assessed against the pressure benchmark using the available evidence. The
benchmarks were designed to provide a ‘standard’ level of pressure against which to assess
sensitivity. Overall, seagrass beds were highly sensitive to a number of human activities:
• penetration or disturbance of the substratum below the surface;
• habitat structure changes – removal of substratum;
• physical change to another sediment type;
• physical loss of habitat;
• siltation rate changes including and smothering; and
• changes in suspended solids.
High sensitivity was recorded for pressures which directly impacted the factors that limit
seagrass growth and health such as light availability. Physical pressures that caused
mechanical modification of the sediment, and hence damage to roots and leaves, also
resulted in high sensitivity.
Seagrass beds were assessed as ‘not sensitive’ to microbial pathogens or ‘removal of target
species’. These assessments were based on the benchmarks used. Z. marina is known to
be sensitive to Labyrinthula zosterae but this was not included in the benchmark used.
Similarly, ‘removal of target species’ addresses only the biological effects of removal and not
the physical effects of the process used. For example, seagrass beds are probably not
sensitive to the removal of scallops found within the bed but are highly sensitive to the
effects of dredging for scallops, as assessed under the pressure penetration or disturbance
of the substratum below the surface‘. This is also an example of a synergistic effect
Assessing the sensitivity of seagrass bed biotopes to pressures associated with marine activities
between pressures. Where possible, synergistic effects were highlighted but synergistic and
cumulative effects are outside the scope off this study.
The report found that no distinct differences in sensitivity exist between the HPI, PMF and
OSPAR definitions. Individual biotopes do however have different sensitivities to pressures.
These differences were determined by the species affected, the position of the habitat on the
shore and the sediment type. For instance evidence showed that beds growing in soft and
muddy sand were more vulnerable to physical damage than beds on harder, more compact
substratum. Temporal effects can also influence the sensitivity of seagrass beds. On a
seasonal time frame, physical damage to roots and leaves occurring in the reproductive
season (summer months) will have a greater impact than damage in winter. On a daily
basis, the tidal regime could accentuate or attenuate the effects of pressures depending on
high and low tide. A variety of factors must therefore be taken into account in order to
assess the sensitivity of a particular seagrass habitat at any location.
No clear difference in resilience was established across the three seagrass definitions
assessed in this report. The resilience of seagrass beds and the ability to recover from
human induced pressures is a combination of the environmental conditions of the site,
growth rates of the seagrass, the frequency and the intensity of the disturbance. This
highlights the importance of considering the species affected as well as the ecology of the
seagrass bed, the environmental conditions and the types and nature of activities giving rise
to the pressure and the effects of that pressure. For example, pressures that result in
sediment modification (e.g. pitting or erosion), sediment change or removal, prolong
recovery. Therefore, the resilience of each biotope and habitat definitions is discussed for
each pressure.
Using a clearly documented, evidence based approach to create sensitivity assessments
allows the assessment and any subsequent decision making or management plans to be
readily communicated, transparent and justifiable. The assessments can be replicated and
updated where new evidence becomes available ensuring the longevity of the sensitivity
assessment tool. The evidence review has reduced the uncertainty around assessments
previously undertaken in the MB0102 project (Tillin et al 2010) by assigning a single
sensitivity score to the pressures as opposed to a range.
Finally, as seagrass habitats may also contribute to ecosystem function and the delivery of
ecosystem services, understanding the sensitivity of these biotopes may also support
assessment and management in regard to these.
Whatever objective measures are applied to data to assess sensitivity, the final sensitivity
assessment is indicative. The evidence, the benchmarks, the confidence in the
assessments and the limitations of the process, require a sense-check by experienced
marine ecologists before the outcome is used in management decisions
An intervention to promote self-management, independence and self-efficacy in people with early-stage dementia : the Journeying through Dementia RCT
Background
There are few effective interventions for dementia.
Aim
To determine the clinical effectiveness and cost-effectiveness of an intervention to promote self-management, independence and self-efficacy in people with early-stage dementia.
Objectives
To undertake a randomised controlled trial of the Journeying through Dementia intervention compared with usual care, conduct an internal pilot testing feasibility, assess intervention delivery fidelity and undertake a qualitative exploration of participants’ experiences.
Design
A pragmatic two-arm individually randomised trial analysed by intention to treat.
Participants
A total of 480 people diagnosed with mild dementia, with capacity to make informed decisions, living in the community and not participating in other studies, and 350 supporters whom they identified, from 13 locations in England, took part.
Intervention
Those randomised to the Journeying through Dementia intervention (n = 241) were invited to take part in 12 weekly facilitated groups and four one-to-one sessions delivered in the community by secondary care staff, in addition to their usual care. The control group (n = 239) received usual care. Usual care included drug treatment, needs assessment and referral to appropriate services. Usual care at each site was recorded.
Main outcome measures
The primary outcome was Dementia-Related Quality of Life score at 8 months post randomisation, with higher scores representing higher quality of life. Secondary outcomes included resource use, psychological well-being, self-management, instrumental activities of daily living and health-related quality of life.
Randomisation and blinding
Participants were randomised in a 1 : 1 ratio. Staff conducting outcome assessments were blinded.
Data sources
Outcome measures were administered in participants’ homes at baseline and at 8 and 12 months post randomisation. Interviews were conducted with participants, participating carers and interventionalists.
Results
The mean Dementia-Related Quality of Life score at 8 months was 93.3 (standard deviation 13.0) in the intervention arm (n = 191) and 91.9 (standard deviation 14.6) in the control arm (n = 197), with a difference in means of 0.9 (95% confidence interval –1.2 to 3.0; p = 0.380) after adjustment for covariates. This effect size (0.9) was less than the 4 points defined as clinically meaningful. For other outcomes, a difference was found only for Diener’s Flourishing Scale (adjusted mean difference 1.2, 95% confidence interval 0.1 to 2.3), in favour of the intervention (i.e. in a positive direction). The Journeying through Dementia intervention cost £608 more than usual care (95% confidence interval £105 to £1179) and had negligible difference in quality-adjusted life-years (–0.003, 95% confidence interval –0.044 to 0.038). Therefore, the Journeying through Dementia intervention had a mean incremental cost per quality-adjusted life-year of –£202,857 (95% confidence interval –£534,733 to £483,739); however, there is considerable uncertainty around this. Assessed fidelity was good. Interviewed participants described receiving some benefit and a minority benefited greatly. However, negative aspects were also raised by a minority. Seventeen per cent of participants in the intervention arm and 15% of participants in the control arm experienced at least one serious adverse event. None of the serious adverse events were classified as related to the intervention.
Limitations
Study limitations include recruitment of an active population, delivery challenges and limitations of existing outcome measures.
Conclusions
The Journeying through Dementia programme is not clinically effective, is unlikely to be cost-effective and cannot be recommended in its existing format.
Future work
Research should focus on the creation of new outcome measures to assess well-being in dementia and on using elements of the intervention, such as enabling enactment in the community.
Trial registration
This trial is registered as ISRCTN17993825
The limitations of in vitro experimentation in understanding biofilms and chronic infection
We have become increasingly aware that during infection, pathogenic bacteria often grow in multi- cellular biofilms which are often highly resistant to antibacterial strategies. In order to understand how biofilms form and contribute to infection, in vitro biofilm systems such as microtitre plate as- says and flow cells, have been heavily used by many research groups around the world. Whilst these methods have greatly increased our understanding of the biology of biofilms, it is becoming increasingly apparent that many of our in vitro methods do not accurately represent in vivo conditions. Here we present a systematic review of the most widely used in vitro biofilm systems, and we discuss why they are not always representative of the in vivo biofilms found in chronic infections. We present examples of methods that will help us to bridge the gap between in vitro and in vivo biofilm work, so that our bench-side data can ultimately be used to improve bedside treatment
Psychology and aggression
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68264/2/10.1177_002200275900300301.pd
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Multi-ancestry genome-wide association analyses improve resolution of genes and pathways influencing lung function and chronic obstructive pulmonary disease risk.
Lung-function impairment underlies chronic obstructive pulmonary disease (COPD) and predicts mortality. In the largest multi-ancestry genome-wide association meta-analysis of lung function to date, comprising 580,869 participants, we identified 1,020 independent association signals implicating 559 genes supported by ≥2 criteria from a systematic variant-to-gene mapping framework. These genes were enriched in 29 pathways. Individual variants showed heterogeneity across ancestries, age and smoking groups, and collectively as a genetic risk score showed strong association with COPD across ancestry groups. We undertook phenome-wide association studies for selected associated variants as well as trait and pathway-specific genetic risk scores to infer possible consequences of intervening in pathways underlying lung function. We highlight new putative causal variants, genes, proteins and pathways, including those targeted by existing drugs. These findings bring us closer to understanding the mechanisms underlying lung function and COPD, and should inform functional genomics experiments and potentially future COPD therapies
Analysis of shared heritability in common disorders of the brain
Paroxysmal Cerebral Disorder
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
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