Evolution of oil droplets in a chemorobotic platform

Evolution, once the preserve of biology, has been widely emulated in software, while physically embodied systems that can evolve have been limited to electronic and robotic devices and have never been artificially implemented in populations of physically interacting chemical entities. Herein we present a liquid-handling robot built with the aim of investigating the properties of oil droplets as a function of composition via an automated evolutionary process. The robot makes the droplets by mixing four different compounds in different ratios and placing them in a Petri dish after which they are recorded using a camera and the behaviour of the droplets analysed using image recognition software to give a fitness value. In separate experiments, the fitness function discriminates based on movement, division and vibration over 21 cycles, giving successive fitness increases. Analysis and theoretical modelling of the data yields fitness landscapes analogous to the genotype–phenotype correlations found in biological evolution. , Trevor Hinkley, James Ward Taylor Kliment Yane

The Evolution of Active Droplets in Chemorobotic Platforms

There is great interest in oil-in-water droplets as simple systems that display astonishingly complex behaviours. Recently, we reported a chemorobotic platform capable of autonomously exploring and evolving the behaviours these droplets can exhibit. The platform enabled us to undertake a large number of reproducible experiments, allowing us to probe the non-linear relationship between droplet composition and behaviour. Herein we introduce this work, and also report on the recent developments we have made to this system. These include new platforms to simultaneously evolve the droplets’ physical and chemical environments and the inclusion of selfreplicating molecules in the droplets

Transcriptome Analysis of \u3ci\u3eBifidobacterium Longum\u3c/i\u3e Strains that Show a Differential Response to Hydrogen Peroxide Stress

Consumer and commercial interest in foods containing probiotic bifidobacteria is increasing. However, because bifidobacteria are anaerobic, oxidative stress can diminish cell viability during production and storage of bioactive foods. We previously found Bifidobacterium longum strain NCC2705 had signifi- cantly greater intrinsic and inducible resistance to hydrogen peroxide (H2O2) than strain D2957. Here, we explored the basis for these differences by examining the transcriptional responses of both strains to sub-lethal H2O2 exposure for 5- or 60-min. Strain NCC2705 had 288 genes that were differentially expressed after the 5-min treatment and 114 differentially expressed genes after the 60-min treatment. In contrast, strain D2957 had only 21 and 90 differentially expressed genes after the 5- and 60-min treatments, respectively. Both strains showed up-regulation of genes coding enzymes implicated in oxidative stress resistance, such as thioredoxin, thioredoxin reductase, peroxiredoxin, ferredoxin, glutaredoxin, and anaerobic ribonucleotide reductase, but induction levels were typically highest in NCC2705. Compared to D2957, NCC2705 also had more up-regulated genes involved in transcriptional regulation and more down-regulated genes involved in sugar transport and metabolism. These results provide a greater understanding of the molecular basis for oxidative stress resistance in B. longum and the factors that contribute to strain-to-strain variability in survival in bioactive food products

Challenges and innovations in the economic evaluation of the risks of climate change

A large discrepancy exists between the dire impacts that most natural scientists project we could face from climate change and the modest estimates of damages calculated by mainstream economists. Economic assessments of climate change risks are intended to be comprehensive, covering the full range of physical impacts and their associated market and non-market costs, considering the greater vulnerability of poor people and the challenges of adaptation. Available estimates still fall significantly short of this goal, but alternative approaches that have been proposed attempt to address these gaps. This review seeks to provide a common basis for natural scientists, social scientists, and modellers to understand the research challenges involved in evaluating the economic risks of climate change. Focusing on the estimation processes embedded in economic integrated assessment models and the concerns raised in the literature, we summarise the frontiers of research relevant to improving quantitative damage estimates, representing the full complexity of the associated systems, and evaluating the impact of the various economic assumptions used to manage this complexity

The impact of decadal-scale Indian Ocean Sea Surface Temperature Anomalies on Sahelian rainfall and the North Atlantic Oscillation

The sea surface temperatures (SSTs) of the tropical Indian Ocean show a pronounced warming since the 1950s. We have analyzed the impact of this warming on Sahelian rainfall and on the North Atlantic Oscillation (NAO) by conducting ensemble experiments with an atmospheric general circulation model. Additionally, we investigate the impact of the other two tropical oceans on these two climate parameters. Our results suggest that the warming trend in the Indian Ocean played a crucial role for the drying trend over the West Sahel from the 1950s to 1990s and may also have contributed to the strengthening of the NAO during the most recent decades

A systematic review and economic evaluation of exercise referral schemes in primary care: a short report

Background - It is estimated that only 39% of men and 29% of women in England achieve the levels of physical activity that are recommended to protect health and prevent disease. One approach to addressing this problem has been the development of exercise referral schemes (ERSs), in which health professionals refer patients to external exercise providers. These schemes have been widely rolled out across the UK despite concerns that they may not produce sustained changes in levels of physical activity and, therefore, may not be cost-effective interventions. The evidence to determine clinical effectiveness and cost-effectiveness was evaluated in 2009. This review seeks to update this earlier work by incorporating new evidence and re-examining the cost-effectiveness. Objectives- To assess the clinical effectiveness and cost-effectiveness of ERSs compared with usual care. Design- Exhaustive searches of relevant electronic databases and journals were undertaken to identify new studies evaluating ERSs using a randomised controlled trial (RCT) design. RCTs that incorporated a qualitative evaluation of the intervention were identified in order to explore the barriers and facilitators to the uptake of and adherence to ERSs. Data were extracted using a previously designed tool and study quality assessed for potential bias. Where data could be pooled, meta-analyses were carried out. Qualitative analysis was also undertaken using a thematic approach. The cost-effectiveness was evaluated using a Markov structure which estimated the likelihood of becoming physically active and the subsequent risk reduction on coronary heart disease (CHD), stroke and type 2 diabetes mellitus. The model adopts a lifetime horizon, and a NHS and Personal Social Services perspective was taken with discounting at 1.5% for both costs and benefits. Results - The search identified one new RCT and one new qualitative study. The new data were pooled with existing data from the 2011 review by Pavey et al. [Pavey TG, Anokye N, Taylor AH, Trueman P, Moxham T, Fox KR, et al. The clinical effectiveness and cost-effectiveness of exercise referral schemes: a systematic review and economic evaluation. Health Technol Assess 2011;15(44)] to give a total of eight studies with 5190 participants. The proportion of individuals achieving 90–150 minutes of at least moderate-intensity activity per week at 6–12 months’ follow-up was greater for ERSs than usual care (relative risk 1.12; 95% confidence interval 1.04 to 1.20). Older patients and those referred for CHD risk factors appeared to be more likely than others to increase their levels of physical activity. Qualitative evidence suggests that interventions enabling the development of social support networks are beneficial in promoting uptake and adherence. Exercise referral gained 0.003 quality-adjusted life-years (QALYs) at an additional cost of £225 per person. The estimated mean incremental cost-effectiveness ratio (ICER) in the probabilistic sensitivity analysis was £76,276. In the univariate sensitivity analysis the results were very sensitive (ICERs ranged from  £100,000) to changes in the effect of ERSs on physical activity uptake and the duration of the protective effects and the direct health-related quality-of-life gains attributable to physical activity. Conclusions - Exercise referral schemes result in a small improvement in the number of people who increase their levels of physical activity. The cost-effectiveness analysis indicates that the ICER for ERSs compared with usual care is around £76,000 per QALY, although the cost-effectiveness of ERSs is subject to considerable uncertainty.National Institute for Health Research Health Technology Assessment programme

Assessing the effect of varying sequence length on DNA barcoding of fungi

DNA barcoding shows enormous promise for the rapid identification of organisms at the species level. There has been much recent debate, however, about the need for longer barcode sequences, especially when these sequences are used to construct molecular phylogenies. Here, we have analysed a set of fungal mitochondrial sequences — of various lengths — and we have monitored the effect of reducing sequence length on the utility of the data for both species identification and phylogenetic reconstruction. Our results demonstrate that reducing sequence length has a profound effect on the accuracy of resulting phylogenetic trees, but surprisingly short sequences still yield accurate species identifications. We conclude that the standard short barcode sequences (∼600 bp) are not suitable for inferring accurate phylogenetic relationships, but they are sufficient for species identification among the fungi

Visualising the complexity of the athlete monitoring cycle through principal component analysis

Purpose: The purpose of this invited commentary is to discuss the use of principal component analysis (PCA) as a dimension reduction and visualisation tool to assist in decision making and communication when analysing complex multivariate data sets associated with the training of athletes. Conclusions: Using PCA it is possible to transform a data matrix into a set of orthogonal composite variables called principal components (PC), with each PC being a linear weighted combination of the observed variables and with all PCs uncorrelated to each other. The benefit of transforming the data using PCA is that the first few PCs generally capture the majority of the information (i.e. variance) contained in the observed data, with the first PC accounting for the highest amount of variance and each subsequent PC capturing less of the total information. Consequently, through PCA it is possible to visualise complex data sets, containing multiple variables on simple 2D scatterplots without any great loss of information, thereby making it much easier to convey complex information to coaches. In the future, athlete monitoring companies should integrate PCA into their client packages to better support practitioners trying to overcome the challenges associated with multivariate data analysis and interpretation. In the interim, we present here an overview of PCA and associated R code to assist practitioners working within the field to integrate PCA into their athlete monitoring process

Rapid degradation of C. elegans proteins at single-cell resolution with a synthetic auxin

ABSTRACT As developmental biologists in the age of genome editing, we now have access to an ever-increasing array of tools to manipulate endogenous gene expression. The auxin-inducible degradation system, allows for spatial and temporal control of protein degradation, functioning through the activity of a hormone-inducible Arabidopsis F-box protein, transport inhibitor response 1 (TIR1). In the presence of auxin, TIR1 serves as a substrate recognition component of the E3 ubiquitin ligase complex SKP1-CUL1-F-box (SCF), ubiquitinating auxin-inducible degron (AID)-tagged proteins for proteasomal degradation. Here, we optimize the Caenorhabditis elegans AID method, utilizing 1-naphthaleneacetic acid (NAA), an indole-free synthetic analog of the natural auxin indole-3-acetic acid (IAA). We take advantage of the photostability of NAA to demonstrate via quantitative high-resolution microscopy that rapid degradation of target proteins can be detected in single cells within 30 minutes of exposure. Additionally, we show that NAA works robustly in both standard growth media and physiological buffer. We also demonstrate that K-NAA, the water-soluble, potassium salt of NAA, can be combined with microfluidics for targeted protein degradation in C. elegans larvae. We provide insight into how the AID system functions in C. elegans by determining that TIR1 interacts with C. elegans SKR-1/2, CUL-1, and RBX-1 to degrade target proteins. Finally, we present highly penetrant defects from NAA-mediated degradation of the Ftz-F1 nuclear hormone receptor, NHR-25, during C. elegans uterine-vulval development. Together, this work provides a conceptual improvement to the AID system for dissecting gene function at the single-cell level during C. elegans development