Ploidy as a leaky reproductive barrier: mechanisms, rates and evolutionary significance of interploidy gene flow.

BACKGROUND: Whole genome duplication (polyploidization) is a dominant force in sympatric speciation, particularly in plants. Genome doubling instantly poses a barrier to gene flow owing to the strong crossing incompatibilities between individuals differing in ploidy. The strength of the barrier, however, varies from species to species and recent genetic investigations revealed cases of rampant interploidy introgression in multiple ploidy-variable species. SCOPE: Here, we review novel insights into the frequency of interploidy gene flow in natural systems and summarize the underlying mechanisms promoting interploidy gene flow. Field surveys, occasionally complemented by crossing experiments, suggest frequent opportunities for interploidy gene flow, particularly in the direction from diploid to tetraploid, and between (higher) polyploids. However, a scarcity of accompanying population genetic evidence and a virtual lack of integration of these approaches leave the underlying mechanisms and levels of realized interploidy gene flow in nature largely unknown. Finally, we discuss potential consequences of interploidy genome permeability on polyploid speciation and adaptation and highlight novel avenues that have just recently been opened by the very first genomic studies of ploidy-variable species. Standing in stark contrast with rapidly accumulating evidence for evolutionary importance of homoploid introgression, similar cases in ploidy-variable systems are yet to be documented. CONCLUSIONS: The genomics era provides novel opportunity to re-evaluate the role of interploidy introgression in speciation and adaptation. To achieve this goal, interdisciplinary studies bordering ecology and population genetics and genomics are needed.

The Prehabilitation Radiotherapy Exercise, smoking Habit cessation and Balanced diet Study (PREHABS) protocol to explore the feasibility of embedding behavioural modifications into the clinical pathway for patients undergoing radical radiotherapy for lung cancer.

Patients with curable non-surgical lung cancer are often current smokers, have co-existing medical comorbidities and are treated with curative radiotherapy. To maximise the benefits of modern radiotherapy, there is an urgent need to optimise the patient's health to improve survival and quality of life. METHODS AND ANALYSIS: The Yorkshire Cancer Research-funded Prehabilitation Radiotherapy Exercise, smoking Habit cessation and Balanced diet Study (PREHABS) (L426) is a single-centre prospective feasibility study to assess embedding behavioural changes into the radical radiotherapy pathway of patients with lung cancer. Feasibility will be assessed by measuring acceptability, demand and implementation. The duration of the study is 24 months. PREHABS has two workstreams: the intervention study and the theory of change (ToC) study.Intervention study: PREHABS will commence at the R-IDEAL phase 2 trial (exploratory) based on existing evidence and includes support for smoking cessation, increasing activity and dietary well-being. Patients undergoing radical radiotherapy for lung cancer will be recruited from the oncology department at Leeds Teaching Hospitals NHS Trust (LTHT). ToC study: to maximise the acceptability and adherence to the PREHABS, we will use a ToC approach to qualitatively explore the key barriers and enablers of implementing a tailored programme of 'prehabilitation'. The PREHABS ToC study participants will be recruited from patients with lung cancer undergoing radical radiotherapy and staff from the LTHT oncology department. ANALYSIS: The primary endpoint analysis will report the number of participants and adherence to the study interventions. Secondary endpoints include continued engagement with study interventions post-treatment. The analysis will focus on descriptive statistics. Thematic analysis of the qualitative data from the ToC study will identify consensus on intervention optimisation and delivery. ETHICS AND DISSEMINATION: On 12 May 2021, the Cambridge East Ethics Committee granted ethical approval (21/EE/0048). The study is registered in the National Institute for Health and Care Research (NIHR) portfolio. The results will be disseminated through publication in peer-reviewed scientific journals and presented at conferences. TRIAL REGISTRATION NUMBER: NIHR portfolio 48420.

Mate-choice for close kin is associated with improved offspring survival in Lodoicea maldivica, the largest-seeded plant in the world.

We studied spatial patterns of kinship in the offspring of the endangered Lodoicea maldivica, a dioecious palm that produces the largest seed of any plant. Previous research has suggested that restricted seed and pollen dispersal in populations resulted in strong spatial genetic structure. We used microsatellites to genotype young plants and their potential parents at four sites across the species' entire natural range. We determined the most likely parents of each young plant based on the spatial separation of each parent pair, their genetic relatedness, and the level of correlated paternity. We identified both parents (43 female, 54 male) for 139 of 493 young plants. Mean distance between parental pairs was 26.8 m. Correlated paternity was low (0.168), indicating that mother trees were often pollinated by several fathers. Parental pairs were more closely related than expected by chance, suggesting outbreeding depression. Our results highlight the apparent strong mate choice for close kin in parent pairs of surviving offspring. We discuss the alternative biological processes that could lead to this, including the potential for break-up of favourable allelic combinations necessary for the development of the palm's very large seed. Management implications include germinating seeds where they naturally fall, using a diverse range of male plants as pollen donors for hand pollination, and protecting the native community of gecko pollinators.

Developing a peer-led intervention to promote COVID-19 testing in low-income housing settings.

Background: The Housing Collaborative project at Eastern Virginia Medical School has developed a method of adapting public health guidance from public housing communities, which face tremendous health challenges in cardiometabolic health, cancer, and other major health conditions. In this paper, we describe how academic and community partners in the Housing Collaborative came together to do this work with a focus on COVID-19 testing in the context of the emerging pandemic. Methods: The academic team used virtual community engagement methods to interact with the Housing Collaborative Community Advisory Board (HCCAB) and a separate cohort of research participants (N = 102) recruited into a study of distrust in COVID-19 guidance. We conducted a series of 44 focus group interviews with participants on related topics. Results from these interviews were discussed with the HCCAB. We used the collaborative intervention planning framework to inform adaptation of public health guidance on COVID-19 testing delivered in low-income housing settings by including all relevant perspectives. Results: Participants reported several important barriers to COVID-19 testing related to distrust in the tests and those administering them. Distrust in housing authorities and how they might misuse positive test results seemed to further undermine decision making about COVID-19 testing. Pain associated with testing was also a concern. To address these concerns, a peer-led testing intervention was proposed by the Housing Collaborative. A second round of focus group interviews was then conducted, in which participants reported their approval of the proposed intervention. Conclusion: Although the COVID-19 pandemic was not our initial focus, we were able to identify a number of barriers to COVID-19 testing in low-income housing settings that can be addressed with adapted public health guidance. We struck a balance between community input and scientific rigor and obtained high quality, honest feedback to inform evidence-based recommendations to guide decisions about health.

I see you, you see me: the impact of social presence on social interaction processes in autistic and non-autistic people.

Environments that require social interaction are complex, challenging and sometimes experienced as overwhelming by autistic people. However, all too often theories relating to social interaction processes are created, and interventions are proposed, on the basis of data collected from studies that do not involve genuine social encounters nor do they consider the perception of social presence to be a potentially influential factor. In this review, we begin by considering why face-to-face interaction research is important in this field. We then discuss how the perception of social agency and social presence can influence conclusions about social interaction processes. We then outline some insights gained from face-to-face interaction research conducted with both autistic and non-autistic people. We finish by considering the impact of social presence on cognitive processes more broadly, including theory of mind. Overall, we demonstrate that choice of stimuli in studies assessing social interaction processes has the potential to substantially alter conclusions drawn. Ecological validity matters and social presence, in particular, is a critical factor that fundamentally impacts social interaction processes in both autistic and non-autistic people. This article is part of a discussion meeting issue 'Face2face: advancing the science of social interaction'.

Gaze cueing, mental States, and the effect of autistic traits.

The ability to interpret and follow the gaze of our social partners is an integral skill in human communication. Recent research has demonstrated that gaze following behaviour is influenced by theory of mind (ToM) processes. However, it has yet to be determined whether the modulation of gaze cueing by ToM is affected by individual differences, such as autistic traits. The aim of this experiment was to establish whether autistic traits in neurotypical populations affect the mediation of gaze cueing by ToM processes. This study used a gaze cueing paradigm within a change detection task. Participants' perception of a gaze cue was manipulated such that they only believed the cue to be able to 'see' in one condition. The results revealed that participants in the Low Autistic Traits group were significantly influenced by the mental state of the gaze cue and were more accurate on valid trials when they believed the cue could 'see'. By contrast, participants in the High Autistic Traits group were also more accurate on valid trials, but this was not influenced by the mental state of the gaze cue. This study therefore provides evidence that autistic traits influence the extent to which mental state attributions modulate social attention in neurotypical adults.

Molar-incisor hypomineralisation combat: exploratory qualitative interviews with general dental practitioners in England regarding the management of children with molar-incisor hypomineralisation.

Introduction Molar-incisor hypomineralisation (MIH) presents as a spectrum, with severe cases becoming increasingly complex to manage. This study aimed to investigate the perceptions and experience of general dental practitioners (GDPs) in England when managing children with MIH.Method Semi-structured telephone interviews with GDPs who regularly treat children took place in May 2020. A sample of four male and six female GDPs with 1-15 years of experience was achieved through purposively sampling interested parties following advertisement via professional groups. Thematic analysis using a realist and inductive approach was used in analysis.Results The overarching theme was of managing uncertainty, with four subthemes: setting the scene; fighting the tooth; working within the system; and self and interpersonal insight. Despite being knowledgeable, participants expressed varying levels of confidence in many aspects while managing children with MIH. There was a great deal of uncertainty surrounding 'doing the right thing' across the themes. Systemic barriers to managing children with MIH within the general dental service were identified.Conclusion The challenges of managing children with MIH was experienced as 'uncertainty'. Barriers within the general dental service made managing children with MIH difficult and participants relied on colleagues in secondary care to manage severe cases.

The Effect of Social Presence on Mentalizing Behavior.

Our behavior is frequently influenced by those around us. However, the majority of social cognition research is conducted using socially isolated paradigms, without the presence of real people (i.e., without a "social presence"). The current study aimed to test the influence of social presence upon a measure of mentalizing behavior in adults. Study 1 used a first-order theory of mind task; and study 2 used a second-order theory of mind task. Both studies included two conditions: live, where the task protagonists were physically present acting out the task, or recorded, where the same task protagonists demonstrated the task in a video recording. In both experiments, participants were affected by the social presence and demonstrated significantly different patterns of behavior in response to the presence of real people. This study, therefore, highlights the critical importance of understanding the effect of a social presence in mentalizing research, and suggests that the inclusion of a social presence needs to be given strong consideration across social cognition paradigms.

Premise typicality as feature inference decision-making in perceptual categories.

Making property inferences for category instances is important and has been studied in two largely separate areas-categorical induction and perceptual categorization. Categorical induction has a corpus of well-established effects using complex, real-world categories; however, the representational basis of these effects is unclear. In contrast, the perceptual categorization paradigm has fostered the assessment of well-specified representation models due to its controlled stimuli and categories. In categorical induction, evaluations of premise typicality effects, stronger attribute generalization from typical category instances than from atypical, have tried to control the similarity between instances to be distinct from premise-conclusion similarity effects, stronger generalization from greater similarity. However, the extent to which similarity has been controlled is unclear for these complex stimuli. Our research embedded analogues of categorical induction effects in perceptual categories, notably premise typicality and premise conclusion similarity, in an attempt to clarify the category representation underlying feature inference. These experiments controlled similarity between instances using overlap of a small number of constrained features. Participants made inferences for test cases using displayed sets of category instances. The results showed typicality effects, premise-conclusion similarity effects, but no evidence of premise typicality effects (i.e., no preference for generalizing features from typical over atypical category instances when similarity was controlled for), with significant Bayesian support for the null. As typicality effects occurred and occur widely in the perceptual categorization paradigm, why was premise typicality absent? We discuss possible reasons. For attribute inference, is premise typicality distinct from instance similarity? These initial results suggest not.

The transitional care pathway following traumatic dental injuries: Patient perspectives.

BACKGROUND AND AIM: The nature of complex traumatic dental injuries (TDIs) often means that management continues through paediatric to adult dental services. Evidence suggests that failure in transitional care can have detrimental impacts on health. There is limited evidence regarding patients' experiences of transitional care pathways (TCPs) in dentistry. The aim of this study was to investigate the views and experiences of the TCP from paediatric to adult care for individuals who have experienced TDIs. MATERIALS AND METHODS: Semi-structured interviews were undertaken. Ethical approval was granted by the Health Research Authority and sponsored by the University of Liverpool. Inclusion criteria included individuals aged 16 to 21 years old who had received care in both paediatric and adult restorative dentistry departments at Liverpool University Dental Hospital following a TDI. Five purposively sampled patients were interviewed. Thematic analysis was undertaken using NVivo. RESULTS: Thematic analysis identified 5 main themes with regard to transitional care experience: patient-clinician communication, impact of dental trauma, feelings of uncertainty, patient personal development and transitional care planning. Feelings of uncertainty with regard to the long-term prognosis of traumatized teeth were highlighted. Clear communication and involvement of young people in decision-making was identified as a vital factor to facilitate a successful TCP experience. CONCLUSION: The involvement of young people in decision-making is essential for a successful TCP. Consideration should be given to development of TCP guidance, to allow for the provision of timely and consistent information regarding the process. Despite this, there needs to be adaptivity within the TCP to create a successful TCP for every young person.

Are they ready? Awareness and preparedness of the emerging workforce for Dental Check by One.

Background Dental Check by One (DCby1) is a British Society of Paediatric Dentistry campaign, which aims to increase dental attendance of young children. As the future workforce, dental students have a key role in ensuring its long-term success.Aims To establish final-year dental students' awareness of DCby1. To evaluate their preparedness for providing dental care for young children and to identify perceived barriers to doing so at the time of graduation as they prepare to enter the workforce.Materials and methods An anonymous, online survey was administered to graduating final-year dental students in 2018, 2019 and 2020. Quantitative data were gathered using mixed item formats and Likert scales. Qualitative data were also gathered using free-text questions, allowing evaluation of the opinions of responders.Results The response rate was 83% (n = 63) in 2018, 91% (n = 62) in 2019 and 73% (n = 57) in 2020. Eight percent (n = 5) of responders were aware of DCby1 in 2018, improving to 67% (n = 38) in 2020. Each year, 98% to 100% of responders felt prepared to provide preventive care for young children. Fewer than 60% felt prepared to provide breastfeeding and weaning advice to parents. Responders felt unprepared to examine the dentition of a preschool child. Undergraduate curricula and social media were identified as preferable sources of public health campaign information for students.Conclusion Awareness and preparedness for DCby1 appears to be improving. Ninety-five percent of all responders across three years of study felt prepared to examine a child aged under one year and this is encouraging for the long-term success of DCby1. Targeted curriculum reform including both didactic teaching and online learning platforms appears to have been pivotal to improving undergraduate awareness and preparedness. Social media may offer opportunities for engaging with undergraduate learners.

An investigation of transitional care pathways for young people following traumatic dental injuries.

Introduction Traumatic dental injuries (TDIs) can cause severe and complex dento-alveolar problems. Management of TDIs frequently extends into adulthood; therefore, a clear transitional care pathway (TCP) is important. Failure of this can prevent engagement in adult dental services and negatively influence treatment outcomes.Aims To assess the availability of TCPs from paediatric and adult specialist care for young people with TDIs.Materials and methods An anonymous, postal survey was designed and administered to all UK specialists in paediatric dentistry registered with the General Dental Council. Quantitative and qualitative data were gathered.Results The response rate was 58% (n = 130). Fifty-five percent (n = 72) stated that there was a dental trauma clinic for children within their locality, while only 22% (n = 29) stated that there was a dental trauma clinic for adults. Sixty-nine percent (n = 90) stated that there was no clear TCP within their locality and 41% (n = 37) of these highlighted a need for a TCP. Thematic analysis of opinions with regards to need for a TCP identified three main themes: pathway availability, access to resources and clinician experience. Following a course of treatment for a patient aged 12 years or above, 24% (n = 31) refer to specialist adult services, with 43% (n = 95) continuing to provide follow-up within paediatric dentistry.Conclusion Follow-up arrangements for young people with TDIs differ across the UK, with inconsistent availability of TCPs. Informal pathways involving referral to multidisciplinary teams may be utilised for follow-up care. Development of a TCP may aid in developing a consistent approach to long-term management of TDIs.

A Qualitative Study of Unfairness and Distrust in Smoke-free Housing.

Objectives: Whereas smoke-free housing (SFH) has the potential to protect residents from tobacco smoke, evidence suggests that SFH could lead to increased indoor smoking. In this study, we examine how perceptions of a residential smoking ban could be related to non-compliance. Methods: We conducted 8 focus group interviews of low-income housing residents living in Norfolk, Virginia (N=53). Interviews were semi-structured and based on a list of guided questions related to SFH compliance, developed in partnership with a standing community advisory board comprised of low-income housing residents. Results: Several themes emerged, including pervasive non-compliance, perceived unfairness and shame, barriers to compliance, and distrust of the housing authority. Smokers reported behavior primarily motivated by punishment avoidance, rather than out of any perceived obligation to comply with the ban. Conclusions: Results led us to consider Procedural Justice Theory as a conceptual framework, in which compliance is directly related to perceptions about the legitimacy of a rule or authority. When compliance is low due to a lack of perceived legitimacy, SFH should be adapted to promote changes in smoking behavior. We offer specific theory-supported adaptations to SFH focused on trust-building and improving perceived fairness.

Disentangling the components of triploid block and its fitness consequences in natural diploid-tetraploid contact zones of Arabidopsis arenosa.

Hybrid seed inviability (HSI) is an important mechanism of reproductive isolation and speciation. HSI varies in strength among populations of diploid species but it remains to be tested whether similar processes affect natural variation in HSI within ploidy-variable species (triploid block). Here we used extensive endosperm, seed and F1 -hybrid phenotyping to explore HSI variation within a diploid-autotetraploid species. By leveraging 12 population pairs from three ploidy contact zones, we tested for the effect of interploidy crossing direction (parent of origin), ploidy divergence and spatial arrangement in shaping reproductive barriers in a naturally relevant context. We detected strong parent-of-origin effects on endosperm development, F1 germination and survival, which was also reflected in the rates of triploid formation in the field. Endosperm cellularization failure was least severe and F1 -hybrid performance was slightly better in the primary contact zone, with genetically closest diploid and tetraploid lineages. We demonstrated overall strong parent-of-origin effects on HSI in a ploidy variable species, which translate to fitness effects and contribute to interploidy reproductive isolation in a natural context. Subtle intraspecific variation in these traits suggests the fitness consequences of HSI are predominantly a constitutive property of the species regardless of the evolutionary background of its populations.

Sensitivity to Social Agency in Autistic Adults.

The presence of other people, whether real or implied, can have a profound impact on our behaviour. However, it is argued that autistic individuals show decreased interest in social phenomena, which leads to an absence of these effects. In this study, the agency of a cue was manipulated such that the cue was either described as representing a computer program or the eye movements of another participant. Both neurotypical and autistic participants demonstrated a social facilitation effect and were significantly more accurate on a prediction task when they believed the cue represented another participant. This demonstrates that whilst autistic adults may show difficulties in interpreting social behaviour this does not necessarily arise from a lack of sensitivity to social agency.

Niche similarity in diploid-autotetraploid contact zones of Arabidopsis arenosa across spatial scales.

PREMISE: Whole genome duplication is a major evolutionary event, but its role in ecological divergence remains equivocal. When populations of different ploidy (cytotypes) overlap in space, "contact zones" are formed, allowing the study of evolutionary mechanisms contributing toward ploidy divergence. Multiple contact zones per species' range are often described but rarely leveraged as natural replicates. We explored whether the strength of niche differentiation of diploid and autotetraploid Arabidopsis arenosa varies over distinct contact zones and if the frequency of triploids decreases from seedling to adult stage. METHODS: We characterized ploidy composition and habitat preferences in 264 populations across three contact zones using climatic niche modeling. Ecological differences of cytotypes were also assessed using local vegetation surveys at 110 populations within two contact zones, and at the finer scale within five mixed-ploidy sites. This was complemented by flow cytometry of seedlings. RESULTS: We found no niche differences between diploid and tetraploid populations within contact zones for either climatic or local environmental variables. Comparisons of cytotypes within mixed-ploidy sites found weak niche differences that were inconsistent in direction. Triploid individuals were virtually absent (0.14%) in the field, and they were at a similarly low frequency (0.2%) in ex situ germinated seedlings. CONCLUSIONS: This study demonstrates the strength in investigating different spatial scales across several contact zones when addressing ecological niche differentiation between ploidies. The lack of consistent habitat differentiation of ploidies across the scales and locations supports the recently emerging picture that processes other than ecological differentiation may underlie ploidy coexistence in diploid-autopolyploid systems.

How accurate are autistic adults and those high in autistic traits at making face-to-face line-of-sight judgements?

LAY ABSTRACT: In order to effectively understand and consider what others are talking about, we sometimes need to follow their line-of-sight to the location at which they are looking, as this can provide important contextual information regarding what they are saying. If we are not able to follow other people's line-of-sight, this could result in social communication difficulties. Here we tested how effectively autistic and neurotypical adults are at following a social partner's line-of-sight during a face-to-face task. In a first study, completed by 14 autistic adult participants of average to above-average verbal ability and 14 neurotypical adult participants, we found that all participants were able to effectively follow the social partner's line-of-sight. We also found that participants tended to be as effective at making these judgements from both a brief, 1s, glance or a long, 5s, stare. However, autistic adults were less accurate, on average, than neurotypical adults overall. In a second study, a separate group of 65 neurotypical adults completed the same line-of-sight judgement task to investigate whether task performance was related to individual variation in self-reported autistic traits. This found that the amount of self-reported autistic traits was not at all related to people's ability to accurately make line-of-sight judgements. This research isolates and furthers our understanding of an important component part of the social communication process and assesses it in a real-world context.

Comparing methods of category learning: Classification versus feature inference.

Categories have at least two main functions: classification of instances and feature inference. Classification involves assigning an instance to a category, and feature inference involves predicting a feature for a category instance. Correspondingly, categories can be learned in two distinct ways, by classification and feature inference. A typical difference between these in the perceptual category learning paradigm is the presence of the category label as part of the stimulus in feature inference learning and not in classification learning. So we hypothesized a label-induced rule-bias in feature inference learning compared to classification and evaluated it on an important starting point in the field for category learning - the category structures from Shepard, Hovland, and Jenkins (Psychological Monographs: General and Applied, 75(13), 1-42, 1961). They classically found that classification learning of structures consistent with more complex rules resulted in poorer learning. We compared feature inference learning of these structures with classification learning and found differences between the learning tasks supporting the label-bias hypothesis in terms of an emphasis on label-based rules in feature inference. Importantly, participants' self-reported rules were largely consistent with their task performance and indicated the preponderance of rule representation in both tasks. So, while the results do not support a difference in the kind of representation for the two learning tasks, the presence of category labels in feature inference tended to focus rule formation. The results also highlight the specialized nature of the classic Shepard et al. (1961) stimuli in terms of being especially conducive to the formation of compact verbal rules.

Identification of sex-linked markers in the sexually cryptic coco de mer: are males and females produced in equal proportions?

Lodoicea maldivica (coco de mer) is a long-lived dioecious palm in which male and female plants are visually indistinguishable when immature, only becoming sexually dimorphic as adults, which in natural forest can take as much as 50 years. Most adult populations in the Seychelles exhibit biased sex ratios, but it is unknown whether this is due to different proportions of male and female plants being produced or to differential mortality. In this study, we developed sex-linked markers in Lodoicea using ddRAD sequencing, enabling us to reliably determine the gender of immature individuals. We screened 589 immature individuals to explore sex ratios across life stages in Lodoicea. The two sex-specific markers resulted in the amplification of male-specific bands (Lm123977 at 405 bp and Lm435135 at 130 bp). Our study of four sub-populations of Lodoicea on the islands of Praslin and Curieuse revealed that the two sexes were produced in approximately equal numbers, with no significant deviation from a 1:1 ratio before the adult stage. We conclude that sex in Lodoicea is genetically determined, suggesting that Lodoicea has a chromosomal sex determination system in which males are the heterogametic sex (XY) and females are homogametic (XX). We discuss the potential causes for observed biased sex ratios in adult populations, and the implications of our results for the life history, ecology and conservation management of Lodoicea.