The Emergence of Predators in Early Life: There was No Garden of Eden

BACKGROUND: Eukaryote cells are suggested to arise somewhere between 0.85~2.7 billion years ago. However, in the present world of unicellular organisms, cells that derive their food and metabolic energy from larger cells engulfing smaller cells (phagocytosis) are almost exclusively eukaryotic. Combining these propositions, that eukaryotes were the first phagocytotic predators and that they arose only 0.85~2.7 billion years ago, leads to an unexpected prediction of a long period (approximately 1-3 billion years) with no phagocytotes -- a veritable Garden of Eden. METHODOLOGY: We test whether such a long period is reasonable by simulating a population of very simple unicellular organisms -- given only basic physical, biological and ecological principles. Under a wide range of initial conditions, cellular specialization occurs early in evolution; we find a range of cell types from small specialized primary producers to larger opportunistic or specialized predators. CONCLUSIONS: Both strategies, specialized smaller cells and phagocytotic larger cells are apparently fundamental biological strategies that are expected to arise early in cellular evolution. Such early predators could have been 'prokaryotes', but if the earliest cells on the eukaryote lineage were predators then this explains most of their characteristic features

1/f noise in patterned GMR spin valves

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The efficacy of social role models to increase motivation to obtain vaccination against hepatitis B among men who have sex with men

This study assessed the effects of role models in persuasive messages about risk and social norms to increase motivation to obtain hepatitis B virus (HBV) vaccination in men who have sex with men (MSM). MSM at risk for HBV in The Netherlands (N = 168) were recruited online via a range of websites and were randomly assigned to one of four conditions in a 2 (risk communication: yes and no) × 2 (social norms communication: yes and no) factorial design. In each condition, participants subsequently provided self-completed assessments of their perceived risk of HBV infection, perceived social norms regarding HBV vaccination and their intention to obtain vaccination against HBV. Risk communication and social norms communication that used social role models were effective in significantly increasing men's intention to obtain vaccination against HBV. No additive effect was found for a combined message. Mediation analyses showed that communications influenced intention via perceived risk and social norms. Findings extend previous theorizing and research and show that both role model-based risk communication and social norms communication can be effective in increasing intentions to obtain HBV vaccination in MSM. This knowledge contributes to the development of effective health promotion to increase HBV vaccination in MSM. © The Author 2010

Self-management of patients with advanced cancer

BACKGROUND: Patients with advanced cancer are increasingly expected to self-manage. Thus far, this topic has received little systematic attention. AIM: To summarise studies describing self-management strategies of patients with advanced cancer and associated experiences and personal characteristics. Also, to summarise attitudes of relatives and healthcare professionals towards patient self-management. DESIGN: A systematic review including non-experimental quantitative and qualitative studies. Data were analysed using critical interpretive synthesis. Included studies were appraised on methodological quality and quality of reporting. DATA SOURCES: MEDLINE, Embase, Cochrane Central, PsycINFO, CINAHL, Web of Science and Google Scholar (until 11 June 2019). RESULTS: Of 1742 identified articles, 31 moderate-quality articles describing 8 quantitative and 23 qualitative studies were included. Patients with advanced cancer used self-management strategies in seven domains: medicine and pharmacology, lifestyle, mental health, social support, knowledge and information, navigation and coordination and medical decision-making (29 articles). Strategies were highly individual, sometimes ambivalent and dependent on social interactions. Older patients and patients with more depressive symptoms and lower levels of physical functioning, education and self-efficacy might have more difficulties with certain self-management strategies (six articles). Healthcare professionals perceived self-management as desirable and achievable if based on sufficient skills and knowledge and solid patient-professional partnerships (three articles). CONCLUSION: Self-management of patients with advanced cancer is highly personal and multifaceted. Strategies may be substitutional, additional or even conflicting compared to care provided by healthcare professionals. Self-management support can benefit from an individualised approach embedded in solid partnerships with relatives and healthcare professionals

Interventions to Promote Cancer Awareness and Early Presentation: Systematic Review

Low cancer awareness contributes to delay in presentation for cancer symptoms and may lead to delay in cancer diagnosis. The aim of this study was to review the evidence for the effectiveness of interventions to raise cancer awareness and promote early presentation in cancer to inform policy and future research. We searched bibliographic databases and reference lists for randomised controlled trials of interventions delivered to individuals, and controlled or uncontrolled studies of interventions delivered to communities. We found some evidence that interventions delivered to individuals modestly increase cancer awareness in the short term and insufficient evidence that they promote early presentation. We found limited evidence that public education campaigns reduce stage at presentation of breast cancer, malignant melanoma and retinoblastoma

Risk factors for delayed presentation and referral of symptomatic cancer: Evidence for common cancers

Background:It has been suggested that the known poorer survival from cancer in the United Kingdom, compared with other European countries, can be attributed to more advanced cancer stage at presentation. There is, therefore, a need to understand the diagnostic process, and to ascertain the risk factors for increased time to presentation.Methods:We report the results from two worldwide systematic reviews of the literature on patient-mediated and practitioner-mediated delays, identifying the factors that may influence these.Results:Across cancer sites, non-recognition of symptom seriousness is the main patient-mediated factor resulting in increased time to presentation. There is strong evidence of an association between older age and patient delay for breast cancer, between lower socio-economic status and delay for upper gastrointestinal and urological cancers and between lower education level and delay for breast and colorectal cancers. Fear of cancer is a contributor to delayed presentation, while sanctioning of help seeking by others can be a powerful mediator of reduced time to presentation. For practitioner delay, ‘misdiagnosis’ occurring either through treating patients symptomatically or relating symptoms to a health problem other than cancer, was an important theme across cancer sites. For some cancers, this could also be linked to inadequate patient examination, use of inappropriate tests or failing to follow-up negative or inconclusive test results.Conclusion:Having sought help for potential cancer symptoms, it is therefore important that practitioners recognise these symptoms, and examine, investigate and refer appropriately. © 2009 Cancer Research UK All rights reserved

CT angiography; useful in non-selected outpatients?

Dance has been a part of the physical education (PE) curriculum in several countries for a longtime. In spite of this, studies demonstrate that the position of dance in the subject of PE iscontested and that little time is devoted to dance. The overall aim of this article is to examine theposition of dance as a pedagogical discourse in Swedish steering documents over time. Theempirical material consists of five Swedish curricula for PE over a period of 50 years (1962–2011).Discourse analysis is used to identify organised systems of meaning, including privileged andprioritised values. Our theoretical frame of reference draws on Bernstein’s concept of codes. Threedifferent knowledge areas within dance are found in the text material: ‘dance as cultural preserver’,‘dance as bodily exercise’ and ‘dance as expression’. Three pedagogical discourses emerge fromthese knowledge areas: an identity formation discourse, a public health discourse and an aestheticdiscourse. The identity formation discourse in earlier curricula focuses on the perpetuation ofSwedish and Nordic cultural traditions, while in later curricula, it emphasises the construction of abroader multicultural identity formation related to the understanding of different cultures. Thepublic health discourse constitutes a prioritised understanding of dance as physical training relatedto a healthy lifestyle. The aesthetic discourse, which has the weakest position over time, representsthe valuing of embodied experiences and feelings expressed through movements. This discourse isclosely linked to the construction of gender. Over time, a new performance code came to surpassthe former competence code in the steering documents. The performance code positions dance inPE as mainly a physical activity with little artistic or aesthetic value. The pedagogical discourse ofdance remains within a highly disciplinary framework of social control