210 research outputs found
Governing the UN Sustainable Development Goals: Interactions, Infrastructures, and Institutions
Three of the eight Millennium Development Goals (MDGs) concerned health. There is only one health goal in 17 proposed Sustainable Development Goals (SDGs). Critiques of the MDGs included missed opportunities to realise positive interactions between goals.
Here we report on an interdisciplinary analytical review of the SDG process, in which experts in different SDG areas identified potential interactions through a series of interdisciplinary workshops. This process generated a framework that reveals potential conflicts and synergies between goals, and how their interactions might be governed
Genome sequencing-assisted identification and the first functional validation ofN-acyl-homoserine-lactone synthases from the Sphingomonadaceae family
Centromere Protein B Null Mice are Mitotically and Meiotically Normal but Have Lower Body and Testis Weights
CENP-B is a constitutive centromere DNA-binding protein that is conserved in a number of mammalian species and in yeast. Despite this conservation, earlier cytological and indirect experimental studies have provided conflicting evidence concerning the role of this protein in mitosis. The requirement of this protein in meiosis has also not previously been described. To resolve these uncertainties, we used targeted disruption of the Cenpb gene in mouse to study the functional significance of this protein in mitosis and meiosis. Male and female Cenpb null mice have normal body weights at birth and at weaning, but these subsequently lag behind those of the heterozygous and wild-type animals. The weight and sperm content of the testes of Cenpb null mice are also significantly decreased. Otherwise, the animals appear developmentally and reproductively normal. Cytogenetic fluorescence-activated cell sorting and histological analyses of somatic and germline tissues revealed no abnormality. These results indicate that Cenpb is not essential for mitosis or meiosis, although the observed weight reduction raises the possibility that Cenpb deficiency may subtly affect some aspects of centromere assembly and function, and result in reduced rate of cell cycle progression, efficiency of microtubule capture, and/or chromosome movement. A model for a functional redundancy of this protein is presented
Electron induced chemistry: a new frontier in astrochemistry
The commissioning of the ALMA array and the next generation of space telescopes heralds the dawn of a new age of Astronomy, in which the role of chemistry in the interstellar medium and in star and planet formation may be quantified. A vital part of these studies will be to determine the molecular complexity in these seemingly hostile regions and explore how molecules are synthesised and survive. The current hypothesis is that many of these species are formed within the ice mantles on interstellar dust grains with irradiation by UV light or cosmic rays stimulating chemical reactions. However, such irradiation releases many secondary electrons which may themselves induce chemistry. In this article we discuss the potential role of such electron induced chemistry and demonstrate, through some simple experiments, the rich molecular synthesis that this may lead to
Extreme energetic electron fluxes in low Earth orbit: Analysis of POES E > 30, E > 100 and E > 300 keV electrons
Energetic electrons are an important space weather hazard. Electrons with energies less than about 100 keV cause surface charging while higher energy electrons can penetrate materials and cause internal charging. In this study we conduct an extreme value analysis of the maximum 3-hourly flux of E> 30 keV, E> 100 keV and E> 300 keV electrons in low Earth orbit as a function of L∗, for geomagnetic field lines that map to the outer radiation belt, using data from the National Oceanic and Atmospheric Administration (NOAA) Polar Operational Environmental Satellites (POES) from July 1998 to June 2014. The 1 in 10 year flux of E> 30 keV electrons shows a general increasing trend with distance ranging from 1.8×107 cm−2s−1sr−1 at L∗ = 3.0 to 6.6×107 cm−2s−1sr−1 at L∗ = 8.0. The 1 in 10 year flux of E> 100 keV electrons peaks at L∗= 4.5 - 5.0 at 1.9×107 cm−2s−1sr−1 decreasing to minima of 7.1×106 and 8.7×106 cm−2s−1sr−1 at L∗ = 3.0 and 8.0 respectively. In contrast to the E> 30 keV electrons, the 1 in 10 year flux of E> 300 keV electrons shows a general decreasing trend with distance, ranging from 2.4×106 cm−2s−1sr−1 at L∗ = 3.0 to 1.2×105 cm−2s−1sr−1 at L∗= 8.0. Our analysis suggests that there is a limit to the E> 30 keV electrons with an upper bound in the range 5.1×107- 8.8×107 cm−2s−1sr−1. However, the results suggest that there is no upper bound for the E> 100 keV and E> 300 keV electrons
First dinosaur from the Isle of Eigg (Valtos Sandstone Formation, Middle Jurassic) Scotland
Dinosaur body fossil material is rare in Scotland, previously known almost exclusively from the Great Estuarine Group on the Isle of Skye. We report the first unequivocal dinosaur fossil from the Isle of Eigg, belonging to a Bathonian (Middle Jurassic) taxon of uncertain affinity. The limb bone NMS G.2020.10.1 is incomplete, but through a combination of anatomical comparison and osteohistology, we determine it most likely represents a stegosaur fibula. The overall proportions and cross-sectional geometry are similar to the fibulae of thyreophorans. Examination of the bone microstructure reveals a high degree of remodelling and randomly distributed longitudinal canals in the remaining primary cortical bone. This contrasts with the histological signal expected of theropod or sauropod limb bones, but is consistent with previous studies of thyreophorans, specifically stegosaurs. Previous dinosaur material from Skye and broadly contemporaneous sites in England belongs to this group, including <jats:italic>Loricatosaurus</jats:italic> and <jats:italic>Sarcolestes</jats:italic> and a number of indeterminate stegosaur specimens. Theropods such as <jats:italic>Megalosaurus</jats:italic> and sauropods such as <jats:italic>Cetiosaurus</jats:italic> are also known from these localities. Although we find strong evidence for a stegosaur affinity, diagnostic features are not observed on NMS G.2020.10.1, preventing us from referring it to any known genera. The presence of this large-bodied stegosaur on Eigg adds a significant new datapoint for dinosaur distribution in the Middle Jurassic of Scotland
Genome Sequencing Shows that European Isolates of Francisella tularensis Subspecies tularensis Are Almost Identical to US Laboratory Strain Schu S4
BACKGROUND: Francisella tularensis causes tularaemia, a life-threatening zoonosis, and has potential as a biowarfare agent. F. tularensis subsp. tularensis, which causes the most severe form of tularaemia, is usually confined to North America. However, a handful of isolates from this subspecies was obtained in the 1980s from ticks and mites from Slovakia and Austria. Our aim was to uncover the origins of these enigmatic European isolates. METHODOLOGY/PRINCIPAL FINDINGS: We determined the complete genome sequence of FSC198, a European isolate of F. tularensis subsp. tularensis, by whole-genome shotgun sequencing and compared it to that of the North American laboratory strain Schu S4. Apparent differences between the two genomes were resolved by re-sequencing discrepant loci in both strains. We found that the genome of FSC198 is almost identical to that of Schu S4, with only eight SNPs and three VNTR differences between the two sequences. Sequencing of these loci in two other European isolates of F. tularensis subsp. tularensis confirmed that all three European isolates are also closely related to, but distinct from Schu S4. CONCLUSIONS/SIGNIFICANCE: The data presented here suggest that the Schu S4 laboratory strain is the most likely source of the European isolates of F. tularensis subsp. tularensis and indicate that anthropogenic activities, such as movement of strains or animal vectors, account for the presence of these isolates in Europe. Given the highly pathogenic nature of this subspecies, the possibility that it has become established wild in the heartland of Europe carries significant public health implications
Group sequential designs in pragmatic trials : feasibility and assessment of utility using data from a number of recent surgical RCTs
Background
Assessing the long term effects of many surgical interventions tested in pragmatic RCTs may require extended periods of participant follow-up to assess effectiveness and use patient-reported outcomes that require large sample sizes. Consequently the RCTs are often perceived as being expensive and time-consuming, particularly if the results show the test intervention is not effective. Adaptive, and particularly group sequential, designs have great potential to improve the efficiency and cost of testing new and existing surgical interventions. As a means to assess the potential utility of group sequential designs, we re-analyse data from a number of recent high-profile RCTs and assess whether using such a design would have caused the trial to stop early.
Methods
Many pragmatic RCTs monitor participants at a number of occasions (e.g. at 6, 12 and 24 months after surgery) during follow-up as a means to assess recovery and also to keep participants engaged with the trial process. Conventionally one of the outcomes is selected as the primary (final) outcome, for clinical reasons, with others designated as either early or late outcomes. In such settings, novel group sequential designs that use data from not only the final outcome but also from early outcomes at interim analyses can be used to inform stopping decisions. We describe data from seven recent surgical RCTs (WAT, DRAFFT, WOLLF, FASHION, CSAW, FIXDT, TOPKAT), and outline possible group sequential designs that could plausibly have been proposed at the design stage. We then simulate how these group sequential designs could have proceeded, by using the observed data and dates to replicate how information could have accumulated and decisions been made for each RCT.
Results
The results of the simulated group sequential designs showed that for two of the RCTs it was highly likely that they would have stopped for futility at interim analyses, potentially saving considerable time (15 and 23 months) and costs and avoiding patients being exposed to interventions that were either ineffective or no better than standard care. We discuss the characteristics of RCTs that are important in order to use the methodology we describe, particularly the value of early outcomes and the window of opportunity when early stopping decisions can be made and how it is related to the length of recruitment period and follow-up.
Conclusions
The results for five of the RCTs tested showed that group sequential designs using early outcome data would have been feasible and likely to provide designs that were at least as efficient, and possibly more efficient, than the original fixed sample size designs. In general, the amount of information provided by the early outcomes was surprisingly large, due to the strength of correlations with the primary outcome. This suggests that the methods described here are likely to provide benefits more generally across the range of surgical trials and more widely in other application areas where trial designs, outcomes and follow-up patterns are structured and behave similarly
Multiway Array Decomposition Analysis of EEGs in Alzheimer’s Disease
Methods for the extraction of features from physiological datasets are growing needs as clinical investigations of Alzheimer’s disease (AD) in large
and heterogeneous population increase. General tools allowing diagnostic regardless of recording sites, such as different hospitals, are essential and if combined to
inexpensive non-invasive methods could critically improve mass screening of subjects with AD. In this study, we applied three state of the art multiway array
decomposition (MAD) methods to extract features from electroencephalograms (EEGs) of AD patients obtained from multiple sites. In comparison to MAD,
spectral-spatial average filter (SSFs) of control and AD subjects were used as well as a common blind source separation method, algorithm for multiple unknown
signal extraction (AMUSE). We trained a feed-forward multilayer perceptron (MLP) to validate and optimize AD classification from two independent databases.
Using a third EEG dataset, we demonstrated that features extracted from MAD outperformed features obtained from SSFs AMUSE in terms of root mean squared
error (RMSE) and reaching up to 100% of accuracy in test condition. We propose that MAD maybe a useful tool to extract features for AD diagnosis offering great
generalization across multi-site databases and opening doors to the discovery of new characterization of the disease
Spores of Clostridium difficile Clinical Isolates Display a Diverse Germination Response to Bile Salts
Clostridium difficile spores play a pivotal role in the transmission of infectious diarrhoea, but in order to cause disease spores must complete germination and return to vegetative cell growth. While the mechanisms of spore germination are well understood in Bacillus, knowledge of C. difficile germination remains limited. Previous studies have shown that bile salts and amino acids play an important role in regulating the germination response of C. difficile spores. Taurocholate, in combination with glycine, can stimulate germination, whereas chenodeoxycholate has been shown to inhibit spore germination in a C. difficile clinical isolate. Our recent studies of C. difficile sporulation characteristics have since pointed to substantial diversity among different clinical isolates. Consequently, in this study we investigated how the germination characteristics of different C. difficile isolates vary in response to bile salts. By analysing 29 isolates, including 16 belonging to the BI/NAP1/027 type, we show that considerable diversity exists in both the rate and extent of C. difficile germination in response to rich medium containing both taurocholate and glycine. Strikingly, we also show that although a potent inhibitor of germination for some isolates, chenodeoxycholate does not inhibit the germination, or outgrowth, of all C. difficile strains. Finally, we provide evidence that components of rich media may induce the germination of C. difficile spores, even in the absence of taurocholate. Taken together, these data suggest that the mechanisms of C. difficile spore germination in response to bile salts are complex and require further study. Furthermore, we stress the importance of studying multiple isolates in the future when analysing the nutrients or chemicals that either stimulate or inhibit C. difficile spore germination
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