281 research outputs found
Merging fragments of classical logic
We investigate the possibility of extending the non-functionally complete
logic of a collection of Boolean connectives by the addition of further Boolean
connectives that make the resulting set of connectives functionally complete.
More precisely, we will be interested in checking whether an axiomatization for
Classical Propositional Logic may be produced by merging Hilbert-style calculi
for two disjoint incomplete fragments of it. We will prove that the answer to
that problem is a negative one, unless one of the components includes only
top-like connectives.Comment: submitted to FroCoS 201
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The Role of Animal Ownership for People with Severe Mental Illness during the COVID-19 Pandemic: A Mixed-Method Study Investigating Links with Health and Loneliness
Research has reported the benefits of companion animals for people with severe mental illness (SMI). However, this evidence base is fragmented and unclear. The COVID-19 pandemic presents an opportunity to explore the role of companion animals in the context of social distancing and isolation measures for people with SMI. Therefore, we aimed to investigate the links between mental and physical health and animal ownership in people with SMI and to explore animal owners’ perceptions related to human–animal interactions during the pandemic restrictions. A survey was conducted with a previously assembled cohort of individuals with SMI in the UK. The survey included previously validated and new bespoke items measuring demographics, and outcomes related to mental and physical health, and human–animal interactions. The survey also included a question inviting free-text responses, allowing participants to describe any experiences of their human–animal relationships during the pandemic. Of 315 participants who consented to participate, 249 (79%) completed the survey. Of these, 115 (46.2%) had at least one companion animal. Regression analyses indicated that animal ownership was not significantly associated with well-being and loneliness. However, animal ownership was associated with a self-reported decline in mental health (b = 0.640, 95% CI [0.102–1.231], p = 0.025), but no self-reported change in physical health. Thematic analysis identified two main themes relating to the positive and negative impact of animal ownership during pandemic restrictions. Animal ownership appeared to be linked to self-reported mental health decline in people with SMI during the second wave of the pandemic in the UK. However, the thematic analysis also highlighted the perceived benefit of animal ownership during this time. Further targeted investigation of the role of human–animal relationships and the perceived human–animal bond for human health is warranted
Popular attitudes to memory, the body, and social identity : the rise of external commemoration in Britain, Ireland, and New England
A comparative analysis of samples of external memorials from burial grounds in Britain, Ireland and New England reveals a widespread pattern of change in monument style and content, and exponential growth in the number of permanent memorials from the 18th century onwards. Although manifested in regionally distinctive styles on which most academic attention has so far been directed, the expansion reflects global changes in social relationships and concepts of memory and the body. An archaeological perspective reveals the importance of external memorials in articulating these changing attitudes in a world of increasing material consumption
The influence of human-animal interactions on mental and physical health during the first Covid-19 lockdown phase in the UK : a qualitative exploration
The Covid-19 pandemic presents an opportunity to explore the role of animals as sources of emotional and physical support during a period when most of the population is experiencing social and environmental challenges. We investigated how companion animal owners perceive the influence of human-animal interaction on their physical and mental health during the first Covid-19 lockdown phase in the UK, and which concerns they may have regarding their animals at this time. We also explored the impact of participants’ interaction with non-companion animals during this phase. A cross-sectional online survey of UK residents aged over 18 was conducted between April and June 2020. The final item of the survey invited open-ended free-text responses, allowing participants to describe any experiences and/or perceptions of their human-animal relationships during the Covid-19 lockdown phase. A qualitative thematic analysis of responses was undertaken. Four main themes related to the following aspects of human-animal interaction during the Covid-19 lockdown phase were identified: positive impact of animal ownership during Covid-19 (e.g. amelioration of wellbeing and mental health); concerns relating to animal ownership during Covid-19 (e.g. concerns over animals carrying the Covid-19 virus); grief and loss of an animal during Covid-19; and impact of engaging with non-companion animals during Covid-19. The findings complement and extend previous insights into the impact of human-animal interaction with both companion and non-companion animals. They also highlight the challenges of caring for an animal during the lockdown phase and indicate the need to consider the development of further targeted support strategies, such as ‘day care’ for companion animal of key workers, in this context
The perceived impact of the first UK Covid-19 lockdown on companion animal welfare and behaviour: a mixed-method study of associations with owner mental health
Background: Companion animals may be a positive presence for their owners during the Covid-19 pandemic. However, the welfare of a companion animal is strongly influenced by the behaviour of their owners, as well as their physical and social environment. We aimed to investigate the reported changes in companion animal welfare and behaviour and to examine the association between these changes and companion animal owners’ mental health. Methods: A cross-sectional online survey of UK residents over 18 years of age was conducted between April and June 2020 (n=5,926). The questionnaire included validated, bespoke items measuring outcomes related to mental health, the hu-man-animal bond and reported changes in animal welfare and behaviour. The final item of the survey invited open-ended free-text responses, allowing participants to describe experiences associated with human-animal relationships during the first UK lockdown phase. Results: Animal owners made up 89.8% of the sample (n=5,323), of whom 67.3% reported changes in their animal’s welfare and behaviour during the first lockdown phase (n=3,583). These reported changes were reduced to a positive (0-7) and negative (0-5) welfare scale, following principal component analysis (PCA) of 17 items. Participants reported more positive changes for cats, whereas more negative changes were reported for dogs. Thematic analysis identified three main themes relating to the positive and negative impact on companion animals of the Covid-19 pandemic. Generalised linear models indicated that companion animal owners with poorer mental health scores pre-lockdown reported fewer negative changes in animal welfare and behaviour. However, companion animal owners with poorer mental health scores since lockdown reported more changes, both positive and negative, in animal welfare and behaviour. Conclusion: Our findings extend previous insights into perceived welfare and behaviour changes on a very limited range of species to a wider a range of companion animals. Owner mental health status has a clear, albeit small, effect on companion animal welfare and behaviour
Ventricular volume expansion in presymptomatic genetic frontotemporal dementia
OBJECTIVE: To characterize the time course of ventricular volume expansion in genetic frontotemporal dementia (FTD) and identify the onset time and rates of ventricular expansion in presymptomatic FTD mutation carriers. METHODS: Participants included patients with a mutation in MAPT, PGRN, or C9orf72, or first-degree relatives of mutation carriers from the GENFI study with MRI scans at study baseline and at 1 year follow-up. Ventricular volumes were obtained from MRI scans using FreeSurfer, with manual editing of segmentation and comparison to fully automated segmentation to establish reliability. Linear mixed models were used to identify differences in ventricular volume and in expansion rates as a function of time to expected disease onset between presymptomatic carriers and noncarriers. RESULTS: A total of 123 participants met the inclusion criteria and were included in the analysis (18 symptomatic carriers, 46 presymptomatic mutation carriers, and 56 noncarriers). Ventricular volume differences were observed 4 years prior to symptom disease onset for presymptomatic carriers compared to noncarriers. Annualized rates of ventricular volume expansion were greater in presymptomatic carriers relative to noncarriers. Importantly, time-intensive manually edited and fully automated ventricular volume resulted in similar findings. CONCLUSIONS: Ventricular volume differences are detectable in presymptomatic genetic FTD. Concordance of results from time-intensive manual editing and fully automatic segmentation approaches support its value as a measure of disease onset and progression in future studies in both presymptomatic and symptomatic genetic FTD
Ventricular volume expansion in presymptomatic genetic frontotemporal dementia
Objective: To characterize the time course of ventricular volume expansion in genetic frontotemporal dementia (FTD) and identify the onset time and rates of ventricular expansion in presymptomatic FTD mutation carriers.
Methods: Participants included patients with a mutation in MAPT, PGRN, or C9orf72, or first-degree relatives of mutation carriers from the GENFI study with MRI scans at study baseline and at 1 year follow-up. Ventricular volumes were obtained from MRI scans using FreeSurfer, with manual editing of segmentation and comparison to fully automated segmentation to establish reliability. Linear mixed models were used to identify differences in ventricular volume and in expansion rates as a function of time to expected disease onset between presymptomatic carriers and noncarriers.
Results: A total of 123 participants met the inclusion criteria and were included in the analysis (18 symptomatic carriers, 46 presymptomatic mutation carriers, and 56 noncarriers). Ventricular volume differences were observed 4 years prior to symptom disease onset for presymptomatic carriers compared to noncarriers. Annualized rates of ventricular volume expansion were greater in presymptomatic carriers relative to noncarriers. Importantly, time-intensive manually edited and fully automated ventricular volume resulted in similar findings.
Conclusions: Ventricular volume differences are detectable in presymptomatic genetic FTD. Concordance of results from time-intensive manual editing and fully automatic segmentation approaches support its value as a measure of disease onset and progression in future studies in both presymptomatic and symptomatic genetic FTD
Descent or Dissent? A future of social work education in the UK post-Brexit
This conceptual paper explores the potential crises arising for social work and social work education following the 2016 ‘Brexit’ referendum in the UK. After exploring the complex political terrain of Brexit voting, the political and moral complications arising, this paper attempts to dispel some of the myths associated with the voter types. Subsequently, the uncertain and possibly dangerous futures of social care and welfare are examined before moving to consider the implications for social work education in the UK, as part of the European Union, and beyond. The need for the UK to continue to pursue its relationships and links with other EU colleagues if social work is not to become parochial and somewhat removed from the international stage is highlighted
Early symptoms in symptomatic and preclinical genetic frontotemporal lobar degeneration
OBJECTIVES: The clinical heterogeneity of frontotemporal dementia (FTD) complicates identification of biomarkers for clinical trials that may be sensitive during the prediagnostic stage. It is not known whether cognitive or behavioural changes during the preclinical period are predictive of genetic status or conversion to clinical FTD. The first objective was to evaluate the most frequent initial symptoms in patients with genetic FTD. The second objective was to evaluate whether preclinical mutation carriers demonstrate unique FTD-related symptoms relative to familial mutation non-carriers.
METHODS: The current study used data from the Genetic Frontotemporal Dementia Initiative multicentre cohort study collected between 2012 and 2018. Participants included symptomatic carriers (n=185) of a pathogenic mutation in chromosome 9 open reading frame 72 (C9orf72), progranulin (GRN) or microtubule-associated protein tau (MAPT) and their first-degree biological family members (n=588). Symptom endorsement was documented using informant and clinician-rated scales.
RESULTS: The most frequently endorsed initial symptoms among symptomatic patients were apathy (23%), disinhibition (18%), memory impairments (12%), decreased fluency (8%) and impaired articulation (5%). Predominant first symptoms were usually discordant between family members. Relative to biologically related non-carriers, preclinical MAPT carriers endorsed worse mood and sleep symptoms, and C9orf72 carriers endorsed marginally greater abnormal behaviours. Preclinical GRN carriers endorsed less mood symptoms compared with non-carriers, and worse everyday skills.
CONCLUSION: Preclinical mutation carriers exhibited neuropsychiatric symptoms compared with non-carriers that may be considered as future clinical trial outcomes. Given the heterogeneity in symptoms, the detection of clinical transition to symptomatic FTD may be best captured by composite indices integrating the most common initial symptoms for each genetic group
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