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Museum DNA reveals a new, potentially extinct species of rinkhals (Serpentes: Elapidae: Hemachatus) from the Eastern Highlands of Zimbabwe
Get PDFGenetic information plays a pivotal role in species recognition and delimitation, but rare or extinct animals can be difficult to obtain genetic samples from. While natural history wet collections have proven invaluable in the description of novel species, the use of these historical samples in genetic studies has been greatly impeded by DNA degradation, especially because of formalin-fixation prior to preservation. Here, we use recently developed museum genomics approaches to determine the status of an isolated population of the elapid snake genus Hemachatus from Zimbabwe. We used multiple digestion phases followed by single strand sequencing library construction and hybridisation capture to obtain 12S and 16S rDNA sequences from a poorly preserved tissue sample of this population. Phylogenetic and morphological analyses in an integrated taxonomic framework demonstrate that the Zimbabwean rinkhals population represents an old and highly distinct lineage, which we describe as a new species, Hemachatus nyangensis sp. nov. Our phylogenetic dating analysis is compatible with venom spitting having evolved in response to the threat posed by early hominins, although more data are required for a robust test of this hypothesis. This description demonstrates the power of museum genomics in revealing rare or even extinct species: Hemachatus from Zimbabwe are only known from a small area of the Eastern Highlands known for high endemism. No living specimens have been seen since the 1980s, most likely due to dramatic land-use changes in the Eastern Highlands, suggesting that the species could be extinct. In view of its recognition as a highly distinct lineage, urgent action is required to determine whether any populations survive, and to safeguard remaining habitat
Terminology and methods used to differentiate injury intent of hospital burn patients in South Asia: a systematic scoping review protocol
Get PDFBACKGROUND: The greatest proportion of burn injuries globally occur in South Asia, where there are also high numbers of intentional burns. Burn injury prevention efforts are hampered by poor surveillance data on injury intent. There is a plethora of local routinely collected data in the research literature from South Asia that could be used for epidemiological purposes, but it is not known whether the definitions and methods of differentiation of injury intent are sufficiently homogenous to allow valid study comparisons.METHODS: We will conduct a systematic scoping review to understand terminology and methods used to differentiate injury intent of hospital burn patients in South Asia. The objectives of the study are to: determine the breadth of terminology and common terms used for burn injury intent; to determine if definitions are comparable across studies where the same term is used; and to appraise the rigour of methods used to differentiate burn injury intent and suitability for comparison across studies. The databases Embase, MEDLINE, CINAHL, PsycINFO, and PakMediNet will be searched. Screening and data extraction will be completed independently by two reviewers. To be included, the article must be as follows: peer reviewed, primary research, study cutaneous burns, based on hospital patients from a country in South Asia, and use intent terminology or discuss a method of differentiation of injury intent. Results will be restricted to English language studies. No date restrictions will be applied. A plain language summary and terminology section are included for non-specialist readers.DISCUSSION: Results will be used to inform stakeholder work to develop standardised terminology and methods for burn injury intent in South Asia. They will be published open access in peer-reviewed journals wherever possible.SYSTEMATIC REVIEW REGISTRATION: This review has been registered with the Open Science Framework ( https://doi.org/10.17605/OSF.IO/DCYNQ ).</p
Late Pleistocene evolution of tides and tidal dissipation
Get PDFStudies of the Last Glacial Maximum (LGM; 26.5–19 ka) tides showed strong enhancements in open ocean tidal amplitudes and dissipation rates; however, changes prior to the LGM remain largely unexplored. Using two different ice sheet and sea level reconstructions, we explicitly simulate the evolution of the leading semi-diurnal and diurnal tidal constituents (M2, S2, K1, and O1) over the last glacial cycle with a global tide model. Both sets of simulations show that global changes, dominated by the Atlantic, take place for the semi-diurnal constituents, while changes for the diurnal constituents are mainly regional. Irrespective of the reconstruction, open ocean dissipation peaks during the sea level lowstands of MIS 2 (∼20 ka) and MIS 4 (∼60 ka), although dissipation values prior to MIS 2 are sensitive to differences in reconstructed ice sheet extent. Using the statistically significant relationship between global mean sea level and dissipation, we apply regression analysis to infer open ocean and shelf dissipation, respectively, over the last four glacial cycles back to 430 ka. Our analysis shows that open ocean tidal energy was probably increased for most of this period, peaking during glacial maxima, and returning to near-present-day values during interglacials. Due to tidal resonance during glacial phases, small changes in bathymetry could have caused large changes in tidal amplitudes and dissipation, emphasizing the need for accurate ice margin reconstructions. During glacial phases, once global mean sea level decreased by more than ∼100 m, the amount of open ocean tidal energy available for ocean mixing approximately doubled
Outdoor Learning Policy, Advocacy and Lobbying in Wales
Get PDFThis article sets out to give you a brief introduction to the journey towards statutory outdoor education provision in Wales. It will also look at the associated challenges faced by researchers, practitioners and even policy makers in achieving meaningful change in the provision of outdoor learning experiences for the children and youngpeople of Wales. It outlines two building blocks that contribute to this process of change, one of which is concerned with curriculum opportunities, whilst the other looks to bring legislative change through a member’s bill in the Welsh Parliament (Senedd Cymru)
Continuous Cover Forestry and Remote Sensing : A Review of Knowledge Gaps, Challenges, and Potential Directions
Get PDFPurpose of ReviewContinuous cover forestry (CCF) is a sustainable management approach for forestry in which forest stands are manipulated to create irregular stand structures with varied species composition. This approach differs greatly from the traditional approaches of plantation-based forestry, in which uniform monocultures are maintained, and thus, traditional methods of assessment, such as productivity (yield class) calculations, are less applicable. This creates a need to identify new methods to succeed the old and be of use in operational forestry and research. By applying remote sensing techniques to CCF, it may be possible to identify novel solutions to the challenges introduced through the adoption of CCF.Recent FindingsThere has been a limited amount of work published on the applications of remote sensing to CCF in the last decade. Research can primarily be characterised as explorations of different methods to quantify the target state of CCF and monitor indices of stand structural complexity during transformation to CCF, using terrestrial and aerial data collection techniques.SummaryWe identify a range of challenges associated with CCF and outline the outstanding gaps within the current body of research in need of further investigation, including a need for the development of new inventory methods using remote sensing techniques. We identify methods, such as individual tree models, that could be applied to CCF from other complex, heterogenous forest systems and propose the wider adoption of remote sensing including information for interested parties to get started
Appropriate design and reporting of superiority, equivalence and non-inferiority clinical trials incorporating a benefit risk assessment: the BRAINS study including expert workshop
Get PDFBackground Randomised controlled trials are designed to assess the superiority, equivalence or non-inferiority of a new health technology, but which trial design should be used is not always obvious in practice. In particular, when using equivalence or non-inferiority designs, multiple outcomes of interest may be important for the success of a trial, despite the fact that usually only a single primary outcome is used to design the trial. Benefit–risk methods are used in the regulatory clinical trial setting to assess multiple outcomes and consider the trade-off of the benefits against the risks, but are not regularly implemented in publicly funded trials.ObjectivesThe aim of the project is to aid the design of clinical trials with multiple outcomes of interest by defining when each trial design is appropriate to use and identifying when to use benefit–risk methods to assess outcome trade-offs (qualitatively or quantitatively) in a publicly funded trial setting.MethodsA range of methods was used to elicit expert opinion to answer the project objectives, including a web-based survey of relevant researchers, a rapid review of current literature and a 2-day consensus workshop of experts (in 2019).ResultsWe created a list of 19 factors to aid researchers in selecting the most appropriate trial design, containing the following overarching sections: population, intervention, comparator, outcomes, feasibility and perspectives. Six key reasons that indicate a benefit–risk method should be considered within a trial were identified: (1) when the success of the trial depends on more than one outcome; (2) when important outcomes within the trial are in competing directions (i.e. a health technology is better for one outcome, but worse for another); (3) to allow patient preferences to be included and directly influence trial results; (4) to provide transparency on subjective recommendations from a trial; (5) to provide consistency in the approach to presenting results from a trial; and (6) to synthesise multiple outcomes into a single metric. Further information was provided to support the use of benefit–risk methods in appropriate circumstances, including the following: methods identified from the review were collated into different groupings and described to aid the selection of a method; potential implementation of methods throughout the trial process were provided and discussed (with examples); and general considerations were described for those using benefit–risk methods. Finally, a checklist of five pieces of information that should be present when reporting benefit–risk methods was defined, with two additional items specifically for reporting the results.ConclusionsThese recommendations will assist research teams in selecting which trial design to use and deciding whether or not a benefit–risk method could be included to ensure research questions are answered appropriately. Additional information is provided to support consistent use and clear reporting of benefit–risk methods in the future. The recommendations can also be used by funding committees to confirm that appropriate considerations of the trial design have been made.LimitationsThis research was limited in scope and should be considered in conjunction with other trial design methodologies to assess appropriateness. In addition, further research is needed to provide concrete information about which benefit–risk methods are best to use in publicly funded trials, along with recommendations that are specific to each method.Study registrationThe rapid review is registered as PROSPERO CRD42019144882
Constructing the school paradox in the lives of children living with parental mental illness
Get PDFChildren living with parental mental illness are referred to as an invisible population because mental health services rarely target them, as the focus is often on the parent who is ill mentally. The same situation occurs even in school where they are unnoticed. This study conducted in Ghana creates awareness about what these children think about their interactions at school in the context of parental mental illness. Data was collected through interviews and diaries with 13 children living with parental mental illness and analysed to attain the essential features through Husserl's transcendental phenomenology. The children find the school as a happy space where they do not have to be worried about the parent's mental illness. Ultimately, though, even at school, most of the children become concerned about the mental wellbeing of the parent due to their loyalty towards them. This results in the school paradox where the children are torn between having their own time at school and being worried about the parent's condition back home, wanting to be there for the parent. The school paradox is an unhealthy cycle that could be addressed with coordinated efforts from mental health professionals, social workers, psychologists and teachers
Does willingness to care fluctuate over time? A weekly diary study among informal caregivers.
Get PDFObjectiveInformal caregivers are expected to be willing to care for relatives with care needs. Little is known about whether and how willingness to care changes over time. Using a weekly diary study, we examined changes in the willingness of 955 caregivers from nine countries. Caregivers provided information on their caregiving context, relationship type, and relationship satisfaction with the care recipient.Methods and measuresFor 24 consecutive weeks, caregivers evaluated willingness to care as it was ‘right now’.ResultsWillingness differs from one caregiver to another (68% between-level variability) but also fluctuates in the same caregiver from week to week (32% within-level variability), with a decrease over 6 months (intercept = 8.55; slope = −0.93; p < .001). Regardless of individual differences in average willingness to care based on caregiving context and relationship satisfaction, caregivers reported decreases in willingness. Caregivers who presented one or more health conditions themselves reported higher weekly fluctuations in willingness than caregivers with no health conditions.ConclusionWillingness is not a stable attitude because it decreases and caregivers experience fluctuations from week to week. A clearer understanding of weekly processes is optimal for monitoring the caregivers’ well-being and tailoring interventions in line with weekly individual variations
Does sand promote or hinder the mobility of cohesive sediment gravity flows?
Get PDFSediment gravity flows exhibit a large range of flow behaviours, making their flow dynamics hard to predict and the resulting deposits a challenge to interpret. Cohesive sediment gravity flows containing clay are particularly complex, as their behaviour is controlled by the balance of turbulent and cohesive forces. A first set of laboratory lock-exchange experiments investigated the effect of adding 25% very fine sand by volume to high-density cohesive sediment gravity flows with strongly suppressed turbulence. This caused these mixed clay–sand flows to become more cohesive, have shorter runout distances, and have lower head velocities than the original pure-clay flows, despite the increase in density difference and the non-cohesive properties of the sand. Yield stress measurements confirmed that adding the non-cohesive very fine sand increases the cohesive strength of dense clay suspensions.This higher cohesive strength outcompetes the enhanced density difference and reduces the flow mobility. A second set of experiments across a larger range of clay concentrations showed that, for low-density cohesive sediment gravity flows dominated by turbulent mixing, the addition of 25% very fine sand increased the head velocities because of the enhanced density difference and weak cohesiveforces. Thus, the addition of very fine sand may increase or decrease the mobility of cohesive sediment gravity flows, depending on the initial type of flow and the balance between turbulent and cohesive forces. In the natural environment, we propose that very fine sand can only increase the cohesive strength and reduce the flow mobility of cohesive sediment gravity flows that have a sufficientlystrong matrix strength to fully support the sand particles. The contribution of very fine sand to the cohesive strength of high-density cohesive sediment gravity flows may have important implications for flow transformation on submarine fans, especially in distal regions where transient-turbulent, cohesive flows are particularly common