How to Measure Group Selection in Real-world Populations

Multilevel selection and the evolution of cooperation are fundamental to the formation of higher-level organisation and the evolution of biocomplexity, but such notions are controversial and poorly understood in natural populations. The theoretic principles of group selection are well developed in idealised models where a population is neatly divided into multiple semi-isolated sub-populations. But since such models can be explained by individual selection given the localised frequency-dependent effects involved, some argue that the group selection concepts offered are, even in the idealised case, redundant and that in natural conditions where groups are not well-defined that a group selection framework is entirely inapplicable. This does not necessarily mean, however, that a natural population is not subject to some interesting localised frequency-dependent effects – but how could we formally quantify this under realistic conditions? Here we focus on the presence of a Simpson’s Paradox where, although the local proportion of cooperators decreases at all locations, the global proportion of cooperators increases. We illustrate this principle in a simple individual-based model of bacterial biofilm growth and discuss various complicating factors in moving from theory to practice of measuring group selection

The development and use of novel iridium complexes as catalysts for ortho-directed hydrogen isotope exchange reactions

The preparation and application of groups of new iridium complexes are described. In particular, iridium complexes possessing phosphine ligands and a bulky N-heterocyclic carbene have been shown to be robust and readily handled species and have been applied in a range of directed hydrogen-deuterium and -tritium exchange processes and, in particular, with drug-like substrates or within ADMET-related studies. Overall, these new iridium(I) complexes are shown to be highly active catalysts and display catalytic activity far in excess of the industry standard, Crabtree's catalyst, with excellent levels of labelling being achieved over short reaction times and at low metal complex loadings, whilst tolerating a wide range of functional moieties. Furthermore and again in contrast to systems employing Crabtree's catalyst, the low catalyst loadings and short reaction times made possible by these emerging iridium carbene comple have delivered tritiated products with very good levels of labelling and without any appreciable by-product waste production

What do we really know about infants who attend Accident and Emergency departments?

Aims: Accident and Emergency attendances continue to rise. Infants are disproportionately represented. This study examines the clinical reasons infants attend UK Accident and Emergency departments. Methods: A retrospective review of 6,667 infants aged less than one year attending Accident and Emergency at two district general hospitals in London from 1st April 2009 to 30th March 2010. All infants had been assigned to a diagnostic category by the medical coding department according to National Health Service (NHS) data guidelines, based on the clinical diagnoses stated in the medical records. The Accident and Emergency case notes of a random subsample of 10% of infants in each of the top five recorded diagnostic categories (n = 535) were reviewed in detail and audited against the standard national NHS data set. Results: The top 5 clinical diagnoses were ‘infectious diseases’, ‘gastrointestinal’, ‘respiratory’, ‘unclassifiable’ and ‘no abnormality detected’ (NAD). A third of infants were originally given a diagnosis of unclassifiable (21.5%) or NAD (11.5%). After detailed case-note review, we were able to reduce this to 9.7% (95% confidence interval (CI): 9.0, 10.4) and 8.8% (95% CI: 8.1, 9.5), respectively. Conclusion: This study demonstrates the importance of providing a clear clinical diagnosis and coding system for Accident and Emergency attendances and understanding that system fully. This would allow for better informed health service evaluation, planning and research as each of these relies on the interpretation of routine health-care data. Furthermore, the relatively high proportion (10%) of infants attending with no discernible underlying medical abnormality suggests the health needs of a significant proportion of infants attending Accident and Emergency departments may be better addressed by alternative service provision and/or improved education and support to parents

From Pisa to Santander : a statement on children's growth and wellbeing

From Pisa to Santander: A Statement on Children's Growth and Wellbeingpeer-reviewe

Gut microbiota influences female choice and fecundity in the nuptial gift-giving species, Drosophila subobscura (Diptera: Drosophilidae)

Recently, there has been rapidly growing interest in the effects of the microbiota on host physiology and behaviour. Due to the nutritional value of bacteria, gut microfl ora may be particularly important in species that present nuptial gifts during courtship. Here, we explore whether the presence or absence of gut microbiota in males and females of the nuptial gift-giving species Drosophila subobscura (Collin, 1936) alters mating behaviour in terms of female preference, male investment, and female fecundity. We found that females that had been fed antibiotics, compared to females with intact gut bacteria, were more willing to mate with a male that had been fed normally. However female fecundity was higher when both males and females lacked gut bacteria compared to both individuals having a full complement of gut bacteria. This implies that the presence of the microbiota acts to reduce female fecundity in this species, and that male gut bacterial content infl uences female fecundity. Our results provide further evidence to the growing consensus that the microbiota of an individual may have important effects on both reproductive behaviour and physiology, and suggest that it may also contribute to the nutritional value of the nuptial gift in this system

Low expression of chloride channel accessory 1 predicts a poor prognosis in colorectal cancer

© 2014 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. Funded by Friends of ANCHOR NHS Grampian Endowment Fund. Grant Number: 12/50Peer reviewe

Relationship between emergency presentation, systemic inflammatory response, and cancer-specific survival in patients undergoing potentially curative surgery for colon cancer

Background Emergency presentation is recognized to be associated with poorer cancer-specific survival following curative resection for colorectal cancer. The present study examined the hypothesis that an enhanced systemic inflammatory response, prior to surgery, might explain the impact of emergency presentation on survival. Methods In all, 188 patients undergoing potentially curative resection for colorectal cancer were studied. Of these, 55 (29%) presented as emergencies. The systemic inflammatory response was assessed using the Glasgow Prognostic Score (mGPS), which is the combination of an elevated C-reactive protein (>10 mg/L) and hypoalbuminemia (<35 g/L). Results In the emergency group, tumor stage was greater (P < 0.01), more patients received adjuvant therapy (P < 0.01) more patients had an elevated mGPS (P < 0.01), and more patients died of their disease (P < 0.05). The minimum follow-up was 12 months; the median follow-up of the survivors was 48 months. Emergency presentation was associated with poorer 3-year cancer-specific survival in those patients aged 65 to 74 years (P < 0.01), in both males and females (P < 0.05), in the deprived (P < 0.01), in patients with tumor-node-metastasis (TNM) stage II disease (P < 0.01), in those who received no adjuvant therapy (P < 0.01), and in the mGPS 0 and 1 groups (P < 0.05) groups. On multivariate survival analysis of patients undergoing potentially curative surgery for TNM stage II colon cancer, emergency presentation (P < 0.05) and mGPS (P < 0.05) were independently associated with cancer-specific survival. Conclusions These results suggest that emergency presentation and the presence of systemic inflammatory response prior to surgery are linked and account for poorer cancer-specific survival in patients undergoing potentially curative surgery for colon cancer. Both emergency presentation and an elevated mGPS should be taken into account when assessing the likely outcome of these patients

Reaching the continuum limit in lattice gauge theory - without a computer

The scaling slope of the anti-symmetric mass gap M of compact U(1)_{2+1} lattice gauge theory is obtained analytically in the Hamiltonian formalism using the plaquette expansion. Based on the first four moments of the Hamiltonian with respect to a one-plaquette mean field state the results demonstrate clear scaling of M at and beyond the transition from strong to weak coupling. The scaling parameters determined agree well with the range of numerical determinations available.Comment: 4 pages, 2 figure