Bistability and Switching Behavior in Moving Animal Groups

Moving animal groups such as schools of fish and flocks of birds frequently switch between different group structures. Standard models of collective motion have been used successfully to explain how stable groups form via local interactions between individuals, but they are typically unable to produce groups that exhibit spontaneous switching. We are only aware of one model, constructed for barred flagtail fish that are known to rely on alignment and attraction to organize their collective motion, that has been shown to generate this type of behavior in 2D (or 3D). Interestingly, another species of fish, golden shiners, do exhibit switching but have been shown to use attraction and repulsion, not alignment, to coordinate themselves in schools. Suggesting that switching may be explained by attraction and repulsion alone, without an alignment interaction. Here we introduce a model based on attraction and repulsion only and show that groups exhibiting switching similar to that observed in experiments with golden shiners emerges. We also establish that switching occur in two boundary-free extensions of the model. Our work suggests that the bistability and switching behavior observed in golden shiners and other moving animal groups may be explained via attractive and repulsive interactions alone

Survey of children accessing HIV services in a high prevalence setting: time for adolescents to count?

OBJECTIVE: To establish the proportion of adolescents among children infected with human immunodeficiency virus (HIV) in Zimbabwe who receive HIV care and support, and what clinic staff perceives to be the main problems faced by HIV-infected children and adolescents. METHODS: In July 2008, we sent a questionnaire to all 131 facilities providing HIV care in Zimbabwe. In it we requested an age breakdown of the children (aged 0-19 years) registered for care and asked what were the two major problems faced by younger children (0-5 years) and adolescents (10-19 years). FINDINGS: Nationally, 115 (88%) facilities responded. In 98 (75%) that provided complete data, 196 032 patients were registered and 24 958 (13%) of them were children. Of children under HIV care, 33% were aged 0-4 years; 25%, 5-9 years; 25%, 10-14 years; and 17%, 15-19 years. Staff highlighted differences in the problems most commonly faced by younger children and adolescents. For younger children, such problems were malnutrition and lack of appropriate drugs (cited by 46% and 40% of clinics, respectively); for adolescents they concerned psychosocial issues and poor drug adherence (cited by 56% and 36%, respectively). CONCLUSION: Interventions for the large cohort of adolescents who are receiving HIV care in Zimbabwe need to target the psychosocial concerns and poor drug adherence reported by staff as being the main concerns in this age group

Fair, Affordable and Open Access to Knowledge: The Caul Collection and Reporting of APC Information Project

Article processing charges (APCs) are fundamental to the business models of many Hybrid and Gold open access (OA) journals. The need to quantify the volume of APC payments paid on behalf of institutional researchers has therefore never been greater. New publishing models will have profound implications for future institutional budgets, and libraries urgently require better information about potential costs and savings. In 2018, the Council of Australian University Librarians (CAUL) commissioned a project to examine the financial impact of APC payments on universities in Australia and New Zealand. The project aims to develop a methodology for the estimation of APC payments based on data from sources such as Scopus, Web of Science and Unpaywall. In order to test this methodology, the Working Group began a pilot project in February 2019. As part of this pilot, data on publications produced by researchers at six local universities in 2017 were collated and analysed. This paper will explain the rationale behind the project methodology. It will present the preliminary findings of the pilot, and flag some of the lessons learnt to date. In addition, the paper will identify future changes. It will be of interest to any librarian concerned with the potential impact of changing publishing models on institutional budgets

Epigenetics as a mechanism driving polygenic clinical drug resistance

Aberrant methylation of CpG islands located at or near gene promoters is associated with inactivation of gene expression during tumour development. It is increasingly recognised that such epimutations may occur at a much higher frequency than gene mutation and therefore have a greater impact on selection of subpopulations of cells during tumour progression or acquisition of resistance to anticancer drugs. Although laboratory-based models of acquired resistance to anticancer agents tend to focus on specific genes or biochemical pathways, such 'one gene : one outcome' models may be an oversimplification of acquired resistance to treatment of cancer patients. Instead, clinical drug resistance may be due to changes in expression of a large number of genes that have a cumulative impact on chemosensitivity. Aberrant CpG island methylation of multiple genes occurring in a nonrandom manner during tumour development and during the acquisition of drug resistance provides a mechanism whereby expression of multiple genes could be affected simultaneously resulting in polygenic clinical drug resistance. If simultaneous epigenetic regulation of multiple genes is indeed a major driving force behind acquired resistance of patients' tumour to anticancer agents, this has important implications for biomarker studies of clinical outcome following chemotherapy and for clinical approaches designed to circumvent or modulate drug resistance

Prevalence of depression and anxiety in patients with cystic fibrosis and parent caregivers: results of The International Depression Epidemiological Study across nine countries

Background Individuals with chronic diseases and parent caregivers are at increased risk for symptoms of depression and anxiety. Prevalence of psychological symptoms was evaluated in adolescents and adults with cystic fibrosis (CF) and parent caregivers across nine countries. Methods Patients with CF, ages 12 years and older, and caregivers of children with CF, birth to18 years of age, completed measures of depression and anxiety across 154 CF centres in Europe and the USA. Psychological symptoms were compared across countries using χ2. Logistic regression examined extent of comorbid symptoms, predictors of depression and anxiety, and concordance between parent and adolescent symptomatology. Results Psychological symptoms were reported by 6088 patients with CF and 4102 parents. Elevated symptoms of depression were found in 10% of adolescents, 19% of adults, 37% of mothers and 31% of fathers. Elevations in anxiety were found in 22% of adolescents, 32% of adults, 48% of mothers and 36% of fathers. Overall, elevations were 2–3 times those of community samples. Participants reporting elevated anxiety were more likely to report depression (ORs: adolescents=14.97, adults=13.64, mothers=15.52, fathers=9.20). Significant differences in reports of depression and anxiety were found by patient age and parent respondent. Concordance between 1122 parent–teen dyads indicated that adolescents whose parents reported depression were more likely to be elevated on depression (OR=2.32). Similarly, adolescents whose parents reported anxiety were more likely to score in the elevated range on the anxiety measure (OR=2.22). Conclusions Symptoms of depression and anxiety were elevated in both patients with CF and parents across several European countries and the USA. Annual screening of psychological symptoms is recommended for both patients and parents

Using Talking Mats to support conversations with communication vulnerable people: A scoping review

BACKGROUND:Talking Mats™ is a framework developed to support communication with communication vulnerable people. OBJECTIVE: The objective was twofold: to provide an overview of the objectives, target groups and settings for which Talking Mats has been used (Part 1), and an overview of empirical scientific knowledge on the use of Talking Mats (Part 2). METHODS: In this scoping review scientific and grey literature was searched in PubMed, Cinahl, Psycinfo, Google, and Google Scholar. Articles that described characteristics of Talking Mats or its use were included. For Part 2, additional selection criteria were applied to focus on empirical scientific knowledge. RESULTS: The search yielded 73 publications in Part 1, 12 of which were included in Part 2. Talking Mats was used for functional objectives (e.g. goal setting) and to improve communication and involvement. Part 2 showed that Talking Mats had positive influences on technical communication, effectiveness of conversations, and involvement and decision making in conversations. However, the level of research evidence is limited. CONCLUSIONS:Talking Mats can be used to support conversations between professionals and communication vulnerable people. More research is needed to study the views of people who are communication vulnerable and to study the effects of Talking Mats

Epigenetic Cross-Talk between DNA Methylation and Histone Modifications in Human Cancers

DNA methylation, histone modifications, and the chromatin structure are profoundly altered in human cancers. The silencing of cancer-related genes by these epigenetic regulators is recognized as a key mechanism in tumor formation. Recent findings revealed that DNA methylation and histone modifications appear to be linked to each other. However, it is not clearly understood how the formation of histone modifications may affect DNA methylation and which genes are relevantly involved with tumor formation. The presence of histone modifications does not always link to DNA methylation in human cancers, which suggests that another factor is required to connect these two epigenetic mechanisms. In this review, examples of studies that demonstrated the relationship between histone modifications and DNA methylation in human cancers are presented and the potential implications of these epigenetic mechanisms in human neoplasia are discussed

Climate change and environmental impacts on maternal and newborn health with focus on Arctic populations

In 2007, the Intergovernmental Panel on Climate Change (IPCC) presented a report on global warming and the impact of human activities on global warming. Later the Lancet commission identified six ways human health could be affected. Among these were not environmental factors which are also believed to be important for human health. In this paper we therefore focus on environmental factors, climate change and the predicted effects on maternal and newborn health. Arctic issues are discussed specifically considering their exposure and sensitivity to long range transported contaminants. Considering that the different parts of pregnancy are particularly sensitive time periods for the effects of environmental exposure, this review focuses on the impacts on maternal and newborn health. Environmental stressors known to affects human health and how these will change with the predicted climate change are addressed. Air pollution and food security are crucial issues for the pregnant population in a changing climate, especially indoor climate and food security in Arctic areas. The total number of environmental factors is today responsible for a large number of the global deaths, especially in young children. Climate change will most likely lead to an increase in this number. Exposure to the different environmental stressors especially air pollution will in most parts of the world increase with climate change, even though some areas might face lower exposure. Populations at risk today are believed to be most heavily affected. As for the persistent organic pollutants a warming climate leads to a remobilisation and a possible increase in food chain exposure in the Arctic and thus increased risk for Arctic populations. This is especially the case for mercury. The perspective for the next generations will be closely connected to the expected temperature changes; changes in housing conditions; changes in exposure patterns; predicted increased exposure to Mercury because of increased emissions and increased biological availability. A number of environmental stressors are predicted to increase with climate change and increasingly affecting human health. Efforts should be put on reducing risk for the next generation, thus global politics and research effort should focus on maternal and newborn health