Reconstruction-classification method for quantitative photoacoustic tomography

We propose a combined reconstruction-classification method for simultaneously recovering absorption and scattering in turbid media from images of absorbed optical energy. This method exploits knowledge that optical parameters are determined by a limited number of classes to iteratively improve their estimate. Numerical experiments show that the proposed approach allows for accurate recovery of absorption and scattering in two and three dimensions, and delivers superior image quality with respect to traditional reconstruction-only approaches

Application of a Fast Parallel EIT Forward Solver to Study the Feasibility of Stroke Type Detection

We present an application of a newly developed fast parallel EIT forward solver (PEITS) implemented in C++. Its features are summarised and the installation, configuration and interface to Matlab are demonstrated. An application of the solver to a feasibility study of stroke type differentiation is illustrated. We found that precise positioning of the electrodes is critical for obtaining good images of stroke

Framework for the development and evaluation of complex interventions: gap analysis, workshop and consultation-informed update.

BACKGROUND: The Medical Research Council published the second edition of its framework in 2006 on developing and evaluating complex interventions. Since then, there have been considerable developments in the field of complex intervention research. The objective of this project was to update the framework in the light of these developments. The framework aims to help research teams prioritise research questions and design, and conduct research with an appropriate choice of methods, rather than to provide detailed guidance on the use of specific methods. METHODS: There were four stages to the update: (1) gap analysis to identify developments in the methods and practice since the previous framework was published; (2) an expert workshop of 36 participants to discuss the topics identified in the gap analysis; (3) an open consultation process to seek comments on a first draft of the new framework; and (4) findings from the previous stages were used to redraft the framework, and final expert review was obtained. The process was overseen by a Scientific Advisory Group representing the range of relevant National Institute for Health Research and Medical Research Council research investments. RESULTS: Key changes to the previous framework include (1) an updated definition of complex interventions, highlighting the dynamic relationship between the intervention and its context; (2) an emphasis on the use of diverse research perspectives: efficacy, effectiveness, theory-based and systems perspectives; (3) a focus on the usefulness of evidence as the basis for determining research perspective and questions; (4) an increased focus on interventions developed outside research teams, for example changes in policy or health services delivery; and (5) the identification of six 'core elements' that should guide all phases of complex intervention research: consider context; develop, refine and test programme theory; engage stakeholders; identify key uncertainties; refine the intervention; and economic considerations. We divide the research process into four phases: development, feasibility, evaluation and implementation. For each phase we provide a concise summary of recent developments, key points to address and signposts to further reading. We also present case studies to illustrate the points being made throughout. LIMITATIONS: The framework aims to help research teams prioritise research questions and design and conduct research with an appropriate choice of methods, rather than to provide detailed guidance on the use of specific methods. In many of the areas of innovation that we highlight, such as the use of systems approaches, there are still only a few practical examples. We refer to more specific and detailed guidance where available and note where promising approaches require further development. CONCLUSIONS: This new framework incorporates developments in complex intervention research published since the previous edition was written in 2006. As well as taking account of established practice and recent refinements, we draw attention to new approaches and place greater emphasis on economic considerations in complex intervention research. We have introduced a new emphasis on the importance of context and the value of understanding interventions as 'events in systems' that produce effects through interactions with features of the contexts in which they are implemented. The framework adopts a pluralist approach, encouraging researchers and research funders to adopt diverse research perspectives and to select research questions and methods pragmatically, with the aim of providing evidence that is useful to decision-makers. FUTURE WORK: We call for further work to develop relevant methods and provide examples in practice. The use of this framework should be monitored and the move should be made to a more fluid resource in the future, for example a web-based format that can be frequently updated to incorporate new material and links to emerging resources. FUNDING: This project was jointly funded by the Medical Research Council (MRC) and the National Institute for Health Research (Department of Health and Social Care 73514)

Investigating the Potential and Pitfalls of EV-Encapsulated MicroRNAs as Circulating Biomarkers of Breast Cancer

Extracellular vesicles (EVs) shuttle microRNA (miRNA) throughout the circulation and are believed to represent a fingerprint of the releasing cell. We isolated and characterized serum EVs of breast tumour-bearing animals, breast cancer (BC) patients, and healthy controls. EVs were characterized using transmission electron microscopy (TEM), protein quantification, western blotting, and nanoparticle tracking analysis (NTA). Absolute quantitative (AQ)-PCR was employed to analyse EV-miR-451a expression. Isolated EVs had the appropriate morphology and size. Patient sera contained significantly more EVs than did healthy controls. In tumour-bearing animals, a correlation between serum EV number and tumour burden was observed. There was no significant relationship between EV protein yield and EV quantity determined by NTA, highlighting the requirement for direct quantification. Using AQ-PCR to relate miRNA copy number to EV yield, a significant increase in miRNA-451a copies/EV was detected in BC patient sera, suggesting potential as a novel biomarker of breast cancer

Long-term trends in human body size track regional variation in subsistence transitions and growth acceleration linked to dairying

Evidence for a reduction in stature between Mesolithic foragers and Neolithic farmers has been interpreted as reflective of declines in health, however, our current understanding of this trend fails to account for the complexity of cultural and dietary transitions or the possible causes of phenotypic change. The agricultural transition was extended in primary centers of domestication and abrupt in regions characterized by demic diffusion. In regions such as Northern Europe where foreign domesticates were difficult to establish, there is strong evidence for natural selection for lactase persistence in relation to dairying. We employ broad-scale analyses of diachronic variation in stature and body mass in the Levant, Europe, the Nile Valley, South Asia, and China, to test three hypotheses about the timing of subsistence shifts and human body size, that: 1) the adoption of agriculture led to a decrease in stature, 2) there were different trajectories in regions of in situ domestication or cultural diffusion of agriculture; and 3) increases in stature and body mass are observed in regions with evidence for selection for lactase persistence. Our results demonstrate that 1) decreases in stature preceded the origins of agriculture in some regions; 2) the Levant and China, regions of in situ domestication of species and an extended period of mixed foraging and agricultural subsistence, had stable stature and body mass over time; and 3) stature and body mass increases in Central and Northern Europe coincide with the timing of selective sweeps for lactase persistence, providing support for the "Lactase Growth Hypothesis.

Parenting, culture, and the development of externalizing behaviors from age 7 to 14 in nine countries

Using multilevel models, we examined mother-, father-, and child-reported (N = 1,336 families) externalizing behavior problem trajectories from age 7 to 14 in nine countries (China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States). The intercept and slope of children\u27s externalizing behavior trajectories varied both across individuals within culture and across cultures, and the variance was larger at the individual level than at the culture level. Mothers’ and children\u27s endorsement of aggression as well as mothers’ authoritarian attitudes predicted higher age 8 intercepts of child externalizing behaviors. Furthermore, prediction from individual-level endorsement of aggression and authoritarian attitudes to more child externalizing behaviors was augmented by prediction from cultural-level endorsement of aggression and authoritarian attitudes, respectively. Cultures in which father-reported endorsement of aggression was higher and both mother- and father-reported authoritarian attitudes were higher also reported more child externalizing behavior problems at age 8. Among fathers, greater attributions regarding uncontrollable success in caregiving situations were associated with steeper declines in externalizing over time. Understanding cultural-level as well as individual-level correlates of children\u27s externalizing behavior offers potential insights into prevention and intervention efforts that can be more effectively targeted at individual children and parents as well as targeted at changing cultural norms that increase the risk of children\u27s and adolescents’ externalizing behavior

Boys’ and Girls’ Relational and Physical Aggression in Nine Countries

Distinguishing between relational and physical aggression has become a key feature of many developmental studies in North America and Western Europe, but very little information is available on relational aggression in more diverse cultural contexts. This study examined the factor structure of, gender differences in, and associations between relational and physical aggression in China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States. Children ages 7 to 10 years (N = 1410) reported on their relationally and physically aggressive behavior. Relational and physical aggression shared a common factor structure across countries. Unsurprisingly, boys reported being more physically aggressive than girls across all nine countries; surprisingly, there were no significant gender differences in relational aggression. In all nine countries, relational and physical aggression were significantly correlated (average r = .49). The countries differed significantly in the mean levels of both relational and physical aggression that children reported using and with respect to whether children reported using more physical than relational aggression or more relational than physical aggression. Despite mean level differences in relational and physical aggression across countries, the findings provided support for cross-country similarities in associations between relational and physical aggression, as well as links between gender and aggression

Mothers\u27, fathers\u27 and children\u27s perceptions of parents\u27 expectations about children\u27s family obligations in nine countries

Children\u27s family obligations involve assistance and respect that children are expected to provide to immediate and extended family members and reflect beliefs related to family life that may differ across cultural groups. Mothers, fathers and children (N = 1432 families) in 13 cultural groups in 9 countries (China, Colombia, Italy, Jordan, Kenya, Philippines, Sweden, Thailand and United States) reported on their expectations regarding children\u27s family obligations and parenting attitudes and behaviours. Within families, mothers and fathers had more concordant expectations regarding children\u27s family obligations than did parents and children. Parenting behaviours that were warmer, less neglectful and more controlling as well as parenting attitudes that were more authoritarian were related to higher expectations regarding children\u27s family obligations between families within cultures as well as between cultures. These international findings advance understanding of children\u27s family obligations by contextualising them both within families and across a number of diverse cultural groups in 9 countries