Degree-equipartite graphs

A graph $G$ of order $2n$ is called degree-equipartite if for every $n$-element set $A\subseteq V(G)$, the degree sequences of the induced subgraphs $G[A]$ and $G[V(G)\setminus A]$ are the same. In this paper, we characterize all degree-equipartite graphs. This answers Problem 1 in the paper by Gr\"{u}nbaum et al [B. Gr\"{u}nbaum, T. Kaiser, D. Kr\'{a}l, and M. Rosenfeld, Equipartite graphs, {\it Israel J. Math.} {\bf 168} (2008), 431-444].Comment: 6 page

An economic model of advance care planning in Australia: A cost-effective way to respect patient choice

© 2017 The Author(s). Background: Advance care planning (ACP) is a process of planning for future health and personal care. A person's values and preferences are made known so that they can guide decision making at a future time when that person cannot make or communicate his or her decisions. This is particularly relevant for people with dementia because their ability to make decisions progressively deteriorates over time. This study aims to evaluate the cost-effectiveness of delivering a nationwide ACP program within the Australian primary care setting. Methods: A decision analytic model was developed to identify the costs and outcomes of an ACP program for people aged 65+ years who were at risk of developing dementia. Inputs for the model was sourced and estimated from the literature. The reliability of the results was thoroughly tested in sensitivity analyses. Results: The results showed that, compared to usual care, a nationwide ACP program for people aged 65+ years who were at risk of dementia would be cost-effective. However, the results only hold if ACP completion is higher than 50% and adherence to ACP wishes is above 75%. Conclusions: A nationwide ACP program in the primary care setting is a cost-effective or cost-saving intervention compared to usual care in a population at-risk of developing dementia. Cost savings are generated from providing treatment and care that is consistent with patient preferences, resulting in fewer hospitalisations and less-intensive care at end-of-life

The vegetation history of an Amazonian domed peatland

The peatland pole forests of the Pastaza-Marañón Foreland Basin (PMFB), Peru, are the most carbon-dense ecosystems known in Amazonia once below ground carbon stores are taken into account. Here we present the first multiproxy palaeoenvironmental record including pollen data from one of these peatlands, San Jorge in northern Peru, supported by an age model based on radiocarbon and 210Pb dating. The pollen data indicate that vegetation changes during the early phases of peat initiation resulted from autogenic succession in combination with fluvial influence. The overall pattern of vegetation change is not straightforward: the record does not reflect a process of unidirectional, progressive terrestrialization, but includes a reversal in the succession and vegetation transitions, which omit predicted successional phases. This complexity is similar to that seen in the only other existing pollen record from a PMFB peatland, at Quistococha, but contrasts with peat records from Panama and Southeast Asia where successional patterning appears more predictable. Our dating results provide the first evidence from a PMFB peatland that peat accumulation may have been discontinuous, with evidence for reduced rates of peat accumulation, or a possible hiatus, around 1300–400 cal yr BP. An ecological shift from open lake to palm swamp occurs at this time, possibly driven by climatic change. The pollen data indicate that the present pole forest vegetation at San Jorge began to assemble c. 200–150 cal yr BP. Given this young age, it is likely that the pole forest at this site remains in a state of transition

Gender diversity among ‘boys’ in Papua New Guinea: Memories of sameness and difference in early childhood

Childhood is a time when children begin to constitute themselves as gendered subjects largely according to social norms that are rigidly framed within dominant discourses of heteronormative binary gender. This paper is based on the life histories of 42 sexuality and gender diverse adult men and transgender women conducted in PNG. Findings offer insight into the ways in which boys transgressed gender norms through dress, play, work within the home and in dance. We argue that gender transgression in childhood is not a contemporary phenomena and such childhood experiences of boys in PNG should be recognised as part of the country's rich cultural diversity

Simultaneous determination of wave speed and arrival time of reflected waves using the pressure-velocity loop

This is the post print version of the article. The official published version can be found at the link below.In a previous paper we demonstrated that the linear portion of the pressure–velocity loop (PU-loop) corresponding to early systole could be used to calculate the local wave speed. In this paper we extend this work to show that determination of the time at which the PU-loop first deviates from linearity provides a convenient way to determine the arrival time of reflected waves (Tr). We also present a new technique using the PU-loop that allows for the determination of wave speed and Tr simultaneously. We measured pressure and flow in elastic tubes of different diameters, where a strong reflection site existed at known distances away form the measurement site. We also measured pressure and flow in the ascending aorta of 11 anaesthetised dogs where a strong reflection site was produced through total arterial occlusion at four different sites. Wave speed was determined from the initial slope of the PU-loop and Tr was determined using a new algorithm that detects the sampling point at which the initial linear part of the PU-loop deviates from linearity. The results of the new technique for detecting Tr were comparable to those determined using the foot-to-foot and wave intensity analysis methods. In elastic tubes Tr detected using the new algorithm was almost identical to that detected using wave intensity analysis and foot-to-foot methods with a maximum difference of 2%. Tr detected using the PU-loop in vivo highly correlated with that detected using wave intensity analysis (r 2 = 0.83, P < 0.001). We conclude that the new technique described in this paper offers a convenient and objective method for detecting Tr, and allows for the dynamic determination of wave speed and Tr, simultaneously

How important is the context of an adolescent's first alcoholic drink? Evidence that parental provision may reduce later heavy episodic drinking

Objective: This study examined the extent to which a retrospective measure of parental provision of the first alcoholic beverage was related to current heavy episodic drinking and current responsible drinking practices. Sample: 608 14- to 17-year-olds from the 2007 Australian National Drug Strategy Household Survey. Measures: Source of first alcoholic beverage (friends/parents/others), source of current alcohol, age of onset of alcohol use, current responsible drinking practices, and proportion of current friends who drink. Results: Binary logistic and multiple regression procedures revealed that parental provision of an adolescent's first alcoholic beverage predicted lower current heavy episodic drinking, and responsible drinking mediated this association. Discussion: The results suggested that for adolescents who become alcohol users, parental provision of the first drink may reduce subsequent alcohol-related risks compared to introduction to alcohol by friends and other sources. Alcohol-related risks remain significant for adolescents who consume alcohol, independent of who is the provider. Copyright (C) 2012 S. Karger AG, Base

Exploring the context of sedentary behaviour in older adults (what, where, why, when and with whom)

BACKGROUND: Older adults are the most sedentary segment of the population. Little information is available about the context of sedentary behaviour to inform guidelines and intervention. There is a dearth of information about when, where to intervene and which specific behaviours intervention should target. The aim of this exploratory study was to obtain objective information about what older adults do when sedentary, where and when they are sedentary and in what social context. METHODS: The study was a cross-sectional data collection. Older adults (Mean age = 73.25, SD ± 5.48, median = 72, IQR = 11) volunteers wore activPAL monitors and a Vicon Revue timelapse camera between 1 and 7 days. Periods of sedentary behaviour were identified using the activPAL and the context extracted from the pictures taken during these periods. Analysis of context was conducted using the Sedentary Behaviour International Taxonomy classification system. RESULTS: In total, 52 days from 36 participants were available for analysis. Participants spent 70.1 % of sedentary time at home, 56.9 % of sedentary time on their own and 46.8 % occurred in the afternoon. Seated social activities were infrequent (6.9 % of sedentary bouts) but prolonged (18 % of sedentary time). Participants appeared to frequently have vacant sitting time (41 % of non-screen sedentary time) and screen sitting was prevalent (36 % of total sedentary time). CONCLUSIONS: This study provides valuable information to inform future interventions to reduce sedentary behaviour. Interventions should consider targeting the home environment and focus on the afternoon sitting time, though this needs confirmation in a larger study. Tackling social isolation may also be a target to reduce sedentary time

Tailored, psychological intervention for anxiety or depression in people with chronic obstructive pulmonary disease (COPD), TANDEM (Tailored intervention for ANxiety and DEpression Management in COPD): protocol for a randomised controlled trial

BACKGROUND: People with chronic obstructive pulmonary disease (COPD) are at increased risk of depression and anxiety, which greatly reduces their quality of life and is associated with worse outcomes; but these psychological co-morbidities are under-recognised and undertreated in COPD patients. Pulmonary rehabilitation (PR) improves mood for up to 6 months but health practitioners under-refer, and patients commonly fail to attend/complete PR. Research suggests that complex non-pharmacological interventions, including both psychological and exercise components, may reduce anxiety and depression in COPD. We have developed a tailored, cognitive behavioural approach (CBA) intervention for patients with COPD and co-morbid anxiety and/or depression ('TANDEM'), which precedes and optimises the benefits of currently offered PR. We hypothesise that such a psychological intervention, delivered by supervised, trained respiratory healthcare professionals, will improve mood in patients with mild to moderate anxiety and/or depression and encourage uptake and completion of PR. METHODS: We will conduct a multi-centre, pragmatic, randomised controlled trial of the TANDEM intervention compared to usual care across the Midlands, London, the South East and Bristol, UK. We will train healthcare professionals familiar with COPD to deliver the manualised, tailored, face-to-face, one-to-one intervention weekly for 6-8 weeks. We will recruit 430 participants from primary, community and secondary care with confirmed COPD and moderate to very severe airflow limitation, who are eligible for assessment for PR, and who screen positive for symptoms of mild/moderate depression and/or anxiety using the Hospital Anxiety and Depression scale (HADS). Participants will be randomised 1.25:1 (intervention: usual care). The co-primary outcomes are the HADS anxiety and depression subscale scores at 6 months; participants will be followed up to 12 months. Secondary outcomes include uptake and completion of PR and healthcare resource use. There will be a parallel process evaluation and a health economic evaluation. DISCUSSION: The TANDEM intervention has the potential to optimise the unrealised synergy between a psychological intervention and PR. The CBA sessions will precede PR and target individuals' cognitions, behaviours and symptoms associated with anxiety and depression to decrease psychological morbidity and increase effective self-management amongst patients with COPD. TRIAL REGISTRATION: ISRCTN, ID: ISRCTN59537391. Registered on 20 March 2017. Protocol version 6.0, 22 April 2018

Emergent dynamic chirality in a thermally driven artificial spin ratchet

Modern nanofabrication techniques have opened the possibility to create novel functional materials, whose properties transcend those of their constituent elements. In particular, tuning the magnetostatic interactions in geometrically frustrated arrangements of nanoelements called artificial spin ice1, 2 can lead to specific collective behaviour3, including emergent magnetic monopoles4, 5, charge screening6, 7 and transport8, 9, as well as magnonic response10, 11, 12. Here, we demonstrate a spin-ice-based active material in which energy is converted into unidirectional dynamics. Using X-ray photoemission electron microscopy we show that the collective rotation of the average magnetization proceeds in a unique sense during thermal relaxation. Our simulations demonstrate that this emergent chiral behaviour is driven by the topology of the magnetostatic field at the edges of the nanomagnet array, resulting in an asymmetric energy landscape. In addition, a bias field can be used to modify the sense of rotation of the average magnetization. This opens the possibility of implementing a magnetic Brownian ratchet13, 14, which may find applications in novel nanoscale devices, such as magnetic nanomotors, actuators, sensors or memory cells