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Approximately, 1.7 million individuals in the United States have been infected with SARS-CoV-2, the virus responsible for the novel coronavirus disease-2019 (COVID-19). This has disproportionately impacted adults, but many children have been infected and hospitalised as well. To date, there is not much information published addressing the cardiac workup and monitoring of children with COVID-19. Here, we share the approach to the cardiac workup and monitoring utilised at a large congenital heart centre in New York City, the epicentre of the COVID-19 pandemic in the United States.
In this paper we explore ancient DNA (aDNA) as a powerful new technique for archaeologists. We argue that for aDNA to reach its full potential we need to carefully consider its theoretical underpinnings. We suggest that at present much aDNA research rests upon two problematic theoretical assumptions: first, that nature and culture exist in binary opposition and that DNA is a part of nature; second, that cultures form distinct and bounded identities. The nature–culture binary, which underpins much aDNA research, not only is a misunderstanding of our world but also results in placing archaeology and material culture in a secondary and subservient position to science and aDNA. Viewing cultures as distinct and bounded creates exclusionary, simplistic and singular identities for past populations. This stands in contrast to the work of social scientists, which has revealed identity to be complex, multiple, changing and contradictory. We offer a new way forward drawing upon assemblage thinking and post-humanism. This allows us to consider the messy and complex nature of our world and of human identities, and demands that we expect equally messy and complex results to emerge when we bring aDNA into conversation with other forms of archaeological evidence.
Destroyed by the eruption of Mount Vesuvius in AD 79, Herculaneum is one of the world's most famous Roman settlements. Exactly how the victims died during the eruption, however, remains unclear. The authors address this issue by examining changes in bone apatite structure and collagen preservation, combined with collagen extraction. Results suggest that the prolonged presence of soft tissue, as well as the stone chambers in which inhabitants had sought shelter, acted as thermal buffers that minimised the heat-induced degradation of skeletal tissues. The results have implications for the interpretation of large residential sites and for contexts where heating and burning is associated with buildings.
Technological advances have led to better patient outcomes and the expansion of clinical services in paediatric cardiology. This expansion creates an ever-growing workload for clinicians, which has led to workflow and staffing issues that need to be addressed. The objective of this study was the development of a novel tool to measure the clinical workload of a paediatric cardiology service in Cape Town, South Africa: The patient encounter index is a tool designed to quantify clinical workload. It is defined as a ratio of the measured duration of clinical work to the total time available for such work. This index was implemented as part of a prospective cross-sectional study design. Clinical workload data were collected over a 10-day period using time-and-motion sampling. Clinicians were contractually expected to spend 50% of their daily workload on patient care. The median patient encounter index for the Western Cape Paediatric Cardiac Service was 0.81 (range 0.19–1.09), reflecting that 81% of total contractual working time was spent on clinical activities. This study describes the development and implementation of a novel tool for clinical workload quantification and describes its application to a busy paediatric cardiology service in Cape Town, South Africa. This tool prospectively quantifies clinical workload which may directly influence patient outcomes. Implementation of this novel tool in the described setting clearly demonstrated the excessive workload of the clinical service and facilitated effective motivation for improved allocation of resources.
Resilience is a cross-disciplinary concept that is relevant for understanding the sustainability of the social and environmental conditions in which we live. Most research normatively focuses on building or strengthening resilience, despite growing recognition of the importance of breaking the resilience of, and thus transforming, unsustainable social-ecological systems. Undesirable resilience (cf. lock-ins, social-ecological traps), however, is not only less explored in the academic literature, but its understanding is also more fragmented across different disciplines. This disparity can inhibit collaboration among researchers exploring interdependent challenges in sustainability sciences. In this article, we propose that the term lock-in may contribute to a common understanding of undesirable resilience across scientific fields.
Cambodia supports populations of three Critically Endangered vulture species that are believed to have become isolated from the rest of the species’ global range. Until recently Cambodia’s vulture populations had remained stable. However a recent spike in the number of reports of the use of poisons in hunting practices suggests the need to re-evaluate the conservation situation in Cambodia. Population trend analysis showed that since 2010 populations of the White-rumped Vulture Gyps bengalensis and Red-headed Vulture Sarcogyps calvus have declined, while the Slender-billed Vulture Gyps tenuirostris may also have started to decline since 2013. These trends are supported by evidence of reduced nesting success. A survey of veterinary drug availability revealed that diclofenac, the non-steroid anti-inflammatory drug responsible for vulture declines in South Asia was not available for sale in any of the 74 pharmacies surveyed. However, a poisoned Slender-billed Vulture tested positive for carbofuran in toxicology tests. This provides the first evidence of a vulture mortality resulting from carbofuran in Cambodia. The findings suggest the urgent need to tackle use of carbamate pesticides in hunting. Proposed conservation actions are: a) prevention of poisoning through national bans on harmful carbamate pesticides and diclofenac and education campaigns to reduce demand and use; b) training of personnel in priority protected areas in detection and response to poisoning incidents; c) maintenance of a safe and reliable food source through vulture restaurants to ensure short-term survival, and d) protection and restoration of large areas of deciduous dipterocarp forests to enable long-term species recovery.
We investigated the association between maternal expressed emotion and twin relationship quality, after controlling for a maternal questionnaire measure of the mother–child relationship. This was explored within a community sample of 156 mothers and their two young twin children (Mchild age = 3.69 years; SDchild age = 0.37). Mothers reported on the twin–twin relationship and the mother–child relationship via questionnaire. They were also interviewed about each child using the innovative Preschool Five Minute Speech Sample (Daley et al., 2003), which yields information about relative positive:negative maternal expressed emotion. Mothers who expressed more family-wide positive emotion and less family-wide negative emotion also reported more positivity, but not negativity, within the twin relationship — even when controlling for questionnaire reports of the mother–child relationship. Counter to expectations, discrepancies in mothers’ expressed emotion between their twins also predicted more positive sibling relationships. Our findings corroborate the well established spill-over effect, whereby families are viewed as emotional units of interdependent individuals, none of whom can be understood in isolation from one another. Most importantly, the Preschool Five Minute Speech Sample provides information about mothering that questionnaire reports may not, and thus it is a useful tool in better understanding the twin family system.
Various practical issues affecting atom probe tomography (APT) analysis of III-nitride semiconductors have been studied as part of an investigation using a c-plane InAlN/GaN heterostructure. Specimen preparation was undertaken using a focused ion beam microscope with a mono-isotopic Ga source. This enabled the unambiguous observation of implantation damage induced by sample preparation. In the reconstructed InAlN layer Ga implantation was demonstrated for the standard “clean-up” voltage (5 kV), but this was significantly reduced by using a lower voltage (e.g., 1 kV). The characteristics of APT data from the desorption maps to the mass spectra and measured chemical compositions were examined within the GaN buffer layer underlying the InAlN layer in both pulsed laser and pulsed voltage modes. The measured Ga content increased monotonically with increasing laser pulse energy and voltage pulse fraction within the examined ranges. The best results were obtained at very low laser energy, with the Ga content close to the expected stoichiometric value for GaN and the associated desorption map showing a clear crystallographic pole structure.
Studies of trade routes across Southeast Asia in prehistory have hitherto focused largely on archaeological evidence from Mainland Southeast Asia, particularly the Thai Peninsula and Vietnam. The role of Indonesia and Island Southeast Asia in these networks has been poorly understood, owing to the paucity of evidence from this region. Recent research has begun to fill this void. New excavations at Sembiran and Pacung on the northern coast of Bali have produced new, direct AMS dates from burials, and analytical data from cultural materials including pottery, glass, bronze, gold andsemi-precious stone, as well as evidence of local bronze-casting. This suggests strong links with the Indian subcontinent and Mainland Southeast Asia from the late first millennium BC, some 200 years earlier than previously thought.
We combine two scanning electron microscopy techniques to investigate the influence of dislocations on the light emission from nitride semiconductors. Combining electron channeling contrast imaging and cathodoluminescence imaging enables both the structural and luminescence properties of a sample to be investigated without structural damage to the sample. The electron channeling contrast image is very sensitive to distortions of the crystal lattice, resulting in individual threading dislocations appearing as spots with black–white contrast. Dislocations giving rise to nonradiative recombination are observed as black spots in the cathodoluminescence image. Comparison of the images from exactly the same micron-scale region of a sample demonstrates a one-to-one correlation between the presence of single threading dislocations and resolved dark spots in the cathodoluminescence image. In addition, we have also obtained an atomic force microscopy image from the same region of the sample, which confirms that both pure edge dislocations and those with a screw component (i.e., screw and mixed dislocations) act as nonradiative recombination centers for the Si-doped c-plane GaN thin film investigated.
The third wave of cognitive behavioural therapies has a developing evidence base and there is an increasing demand for specialist training. However, methods for training clinicians have not yet been evaluated in terms of effectiveness and usefulness. This evaluation seeks to assess: (1) the effectiveness of one-day introductory Acceptance and Commitment Therapy (ACT) workshops for clinicians in a NHS setting in terms of increasing knowledge of ACT; (2) the impact of experiential techniques as a method for delivering ACT training. A total of 73 participants took part in the workshops and completed questionnaires were administered pre-workshop and post-workshop; a further 29 participants completed follow-up questionnaire after 12 months. Participants demonstrated an increase in ACT knowledge, indicated that their interest had been stimulated, viewed the workshop positively and reported that their clinical work had been influenced by the workshop. In terms of the training process, experiential techniques are integral to ACT practice and training. Participants reported that their training experiences and engagement with the training group had not been aversive. Moreover, there was no evidence that participants’ own levels of experiential avoidance had affected training outcomes.
Fast-turnaround, accurate methods for the assessment of threading dislocation densities in GaN are an essential research tool. Here, we present an in-situ surface treatment for use in MOVPE (metal-organic vapour phase epitaxy) growth, in which GaN is exposed to a SiH4 flux at 860 °C in the presence of NH3. Subsequent characterisation by atomic force microscopy shows that the treatment is effective in increasing edge and mixed/screw dislocation pit sizes on both n- and p-type material, and on partially coalesced GaN layers.
Gross well-width fluctuations have been observed in single green-emitting InGaN/GaN quantum wells (QWs) grown by two methods: (i) a “two-temperature” method, where the GaN barrier has been grown at a higher temperature than the InGaN layer, (ii) a single-temperature method, where the InGaN was annealed in a flow of NH3/N2, prior to capping. InGaN epilayers analogous to these QW structures have been grown and characterized by atomic force microscopy (AFM) and transmission electron microscopy (TEM). AFM reveals a network of interlinking InGaN strips. Compositional analysis across the InGaN strips has shown that the centres of these strips to be indium-rich compared to the strip-edges. Furthermore, we have correlated the position of threading dislocations (TDs) in relation to these InGaN strips and determined that 90 % of the TDs terminate at the channels between the InGaN strips or near the edges of the strips. We propose that confinement of charge carriers occurs in the indium-rich regions at the centre of the InGaN strips, preventing non-radiative recombination losses at dislocation sites.
The mean inner potentials of wurtzite GaN nanowires are measured using off-axis electron holography in the transmission electron microscope (TEM). The nanowires have a circular cross-section and are suspended across holes in a holey carbon film, resulting in an accurate knowledge of their thickness profiles and orientations. They are also free of the implantation and damage that is present in mechanically-polished ion-milled TEM specimens. The effect of a thin amorphous coating, which is present on the surfaces of the nanowires, on measurements of their mean inner potential is assessed. A value for the mean inner potential of GaN of (16.7 ± 0.3) V is obtained from these samples.
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