The commonly-used DNA probe for diffusely-adherent Escherichia coli cross-reacts with a subset of enteroaggregative E. coli.

yesBackground. The roles of diffusely-adherent Escherichia coli (DAEC) and enteroaggregative E. coli (EAEC) in disease are not well understood, in part because of the limitations of diagnostic tests for each of these categories of diarrhoea-causing E. coli. A HEp-2 adherence assay is the Gold Standard for detecting both EAEC and DAEC but DNA probes with limited sensitivity are also employed. Results. We demonstrate that the daaC probe, conventionally used to detect DAEC, cross-reacts with a subset of strains belonging to the EAEC category. The cross hybridization is due to 84% identity, at the nucleotide level, between the daaC locus and the aggregative adherence fimbriae II cluster gene, aafC, present in some EAEC strains. Because aaf-positive EAEC show a better association with diarrhoea than other EAEC, this specific cross-hybridization may have contributed to an over-estimation of the association of daaC with disease in some studies. We have developed a discriminatory PCR-RFLP protocol to delineate EAEC strains detected by the daaC probe in molecular epidemiological studies. Conclusions. A PCR-RFLP protocol described herein can be used to identify aaf-positive EAEC and daaC-positive DAEC and to delineate these two types of diarrhoeagenic E. coli, which both react with the daaC probe. This should help to improve current understanding and future investigations of DAEC and EAEC epidemiology

IS3 Profiling Identifies the Enterohaemorrhagic Escherichia Coli O-island 62 in a Distinct Enteroaggregative E. Coli Lineage

We identify a marker for potentially pathogenic enteroaggregative Escherichia coli using a method that we devised that could be applied to similar problems in other organisms. --author-supplied descriptio

Enhancement of luminescence by pulse laser annealing of ion-implanted europium in sapphire and silica

Sapphire (Al2O3) and silica samples have been implanted with 400 keV europium ions at fluences between 5×1014 and 1×1016 ions cm-2. As-implanted, samples show luminescence at 622 nm, and although the intensity may be increased by furnace anneals up to 1000°C, higher temperatures, to 1200°C, result in less emission, as the impurity ions form precipitate clusters. This problem can be avoided by the use of pulsed laser anneals which dissociate the clusters and quench in atomically dispersed ions. The luminescence intensity has been increased by factors of 95 and 85 for sapphire and silica, respectively, relative to the initial implanted signal. On comparing with furnace anneals at 1200°C, the pulsed laser annealing is more effective, by factors of up to 45 times. Data for pulsed excimer and CO2 lasers are compared. Both types of laser appear to remove the ion-implanted radiation damage, but in the case of silica, higher luminescence performance was obtained with the excimer anneals. There was no evidence for diffusion of the implanted europium, as assessed by Rutherford backscattering spectrometry. © 1995 American Institute of Physics.We thank Barry Farmery for his help with the RBS work, and both the University of Ege in Turkey and the Science and Engineering Research Council for their financial assistance. We appreciate the use of a Lumonics (Hull Op- erations) Ltd. TEA CO, laser.Peer Reviewe

A stratigraphical basis for the Anthropocene?

Recognition of intimate feedback mechanisms linking changes across the atmosphere, biosphere, geosphere and hydrosphere demonstrates the pervasive nature of humankind's influence, perhaps to the point that we have fashioned a new geological epoch, the Anthropocene. To what extent will these changes be evident as long-lasting signatures in the geological record? To establish the Anthropocene as a formal chronostratigraphical unit it is necessary to consider a spectrum of indicators of anthropogenically induced environmental change, and to determine how these show as stratigraphic signals that can be used to characterize an Anthropocene unit and to recognize its base. It is important to consider these signals against a context of Holocene and earlier stratigraphic patterns. Here we review the parameters used by stratigraphers to identify chronostratigraphical units and how these could apply to the definition of the Anthropocene. The onset of the range of signatures is diachronous, although many show maximum signatures which post-date1945, leading to the suggestion that this date may be a suitable age for the start of the Anthropocene

Spin splitting of X-related donor impurity states in an AlAs barrier

We use magnetotunneling spectroscopy to observe the spin splitting of the ground state of an X-valley-related Si-donor impurity in an AlAs barrier. We determine the absolute magnitude of the effective Zeeman spin splitting factors of the impurity ground state to be g$_{I}$= 2.2 $\pm$ 0.1. We also investigate the spatial form of the electron wave function of the donor ground state, which is anisotropic in the growth plane

A platform in the use of medicines to treat chronic hepatitis C (PLATINUM C) protocol for a prospective treatment registry of real world o

Background Safe, highly curative, short course, direct acting antiviral (DAA) therapies are now available to treat chronic hepatitis C. DAA therapy is freely available to all adults chronically infected with the hepatitis C virus (HCV) in Australia. If left untreated, hepatitis C may lead to progressive hepatic fibrosis, cirrhosis and hepatocellular carcinoma. Australia is committed to eliminating hepatitis as a public health threat by 2030 set by the World Health Organization. However, since the introduction of funded DAA treatment, uptake has been suboptimal. Australia needs improved strategies for testing, treatment uptake and treatment completion to address the persisting hepatitis C public health problem. PLATINUM C is a HCV treatment registry and research platform for assessing the comparative effectiveness of alternative interventions for achieving virological cure. Methods PLATINUM C will prospectively enrol people with active HCV infection confirmed by recent detection of HCV ribonucleic acid (RNA) in blood. Those enrolled will agree to allow standardised collection of demographic, lifestyle, treatment, virological outcome and other relevant clinical data to better inform the future management of HCV infection. The primary outcome is virological cure evidenced by sustained virological response (SVR), which is defined as a negative HCV PCR result 6 to 18 months after initial prescription of DAA therapy and no less than 12 weeks after the completion of treatment. Study participants will be invited to opt-in to medication adherence monitoring and quality of life assessments using validated self-reported instruments (EQ-5D-5L). Discussion PLATINUM C is a treatment registry and platform for nesting pragmatic trials. Data collected will inform the design, development and implementation of pragmatic trials. The digital infrastructure, study procedures and governing systems established by the registry will allow PLATINUM C to support a wider research platform in the management of hepatitis C in primary care. Trial registration The trial is registered with the Australia and New Zealand Clinical Trials Register (ACTRN12619000023156). Date of registration: 10/01/2019

Mechanisms of population structuring in giant Australian cuttlefish Sepia apama

While a suite of approaches have been developed to describe the scale, rate and spatial structure of exchange among populations, a lack of mechanistic understanding will invariably compromise predictions of population-level responses to ecosystem modification. In this study, we measured the energetics and sustained swimming capacity of giant Australian cuttlefish Sepia apama and combined these data with information on the life-history strategy, behaviour and circulation patterns experienced by the species to predict scales of connectivity throughout parts of their range. The swimming capacity of adult and juvenile S. apama was poor compared to most other cephalopods, with most individuals incapable of maintaining swimming above 15 cm s−1. Our estimate of optimal swimming speed (6–7 cm s−1) and dispersal potential were consistent with the observed fine-scale population structure of the species. By comparing observed and predicted population connectivity, we identified several mechanisms that are likely to have driven fine-scale population structure in this species, which will assist in the interpretation of future population declines.Nicholas L. Payne, Edward P. Snelling, Jayson M. Semmens, Bronwyn M. Gillander

Profile of the Spleen Transcriptome in Beef Steers with Variation in Gain and Feed Intake

We have previously identified components of the immune system contributing to feed intake and gain in both the rumen and small intestine of beef steers. In this study, we examined the spleen, a major lymphatic organ near the digestive tract, to determine whether it was also influencing individual feed efficiency status through immune responses. Animals (n=16) that were divergent for gain and intake were selected for tissue sampling. The spleen transcriptomes were evaluated by microarray. A total of 1,216 genes were identified as differentially expressed. Genes were over-represented in Kyoto encyclopedia of genes and genomes (KEGG) pathways including biological regulation, protein folding, cell communication, immune systems process, response to stress and RNA metabolic process. Several stress response or heat shock genes including HSPH1, HSPA1A, HSPA4, DNAJB4, DNAJA4, etc., were identified as a stress response functional gene cluster in the low gain-low intake animals. These genes were up-regulated amongst the low gain-low intake animals compared to all other groups. Canonical pathways associated with the differentially expressed genes included the coagulation system, extrinsic prothrombin activation, protein ubiquitination, unfolded protein response and aldosterone signaling in epithelial cells. An analysis of expressed copy number variable (CNV) genes in the spleen produced some of the same genes and gene families that were differentially expressed. Our data suggests the splenic contribution to some of the underlying variation among gain and intake within this group of animals may be a result of immune function and stress response. In addition, some of the differences in immune response functions may be related to gene copy number

Edades radiométricas de los edificios miocenos de Fuerteventura (Islas Canarias).

Se han realizado once nuevas dataciones K-Ar de las coladas básicas (basaltos, nefelinitas) y sálicas (traquitas) de los tres edificios principales subaéreos (Tetir o Norte, Gran Tarajal o Central y Jandía o Sur) que constituyen la Fase miocena de la isla. Se precisa algo más la cronoestratigrafía relativa entre ellos, así como la correspondiente a los tramos que los integran

Coverage gaps in empiric antibiotic regimens used to treat serious bacterial infections in neonates and children in Southeast Asia and the Pacific

Background: High levels of antimicrobial resistance (AMR) are propagating deaths due to neonatal and paediatric infections globally. This is of particular concern in Southeast Asia and the Pacific, where healthcare resources are constrained and access to newer agents to treat multidrug-resistant pathogens is limited. Methods: To assess the coverage provided by commonly prescribed empiric antibiotic regimens for children in low- and middle-income countries in Southeast Asia and the Pacific, we built a weighted incidence syndromic combination antibiogram (WISCA), parameterised using data obtained from a systematic review of published literature incorporating WHO-defined SEARO and WPRO regions in Ovid MEDLINE, EMBASE, Global Health and PubMed. Susceptibility data for bacterial pathogens were extracted to provide coverage estimates for pre-specified antibiotics (aminopenicillins, gentamicin, third-generation cephalosporins and carbapenems), reported at the regional level. Findings: 6648 bacterial isolates from 11 countries across 86 papers were included in the Bayesian WISCA model, which weighted bacterial incidence and antimicrobial susceptibility of relevant isolates. Coverage provided by aminopenicillins in neonatal sepsis/meningitis was 26% (80% credible interval: 16–49) whilst gentamicin coverage was 45% (29–62). Third-generation cephalosporin coverage was only 29% (16–49) in neonatal sepsis/meningitis, 51% (38–64) in paediatric sepsis and 65% (51–77) in paediatric meningitis. Carbapenems were estimated to provide the highest coverage: 81% (65–90) in neonatal sepsis/meningitis, 83% (72–90) in paediatric sepsis and 79% (62–91) in paediatric meningitis. Interpretation: These findings reveal alarmingly high rates of resistance to commonly prescribed empirical therapies for neonatal and paediatric sepsis and meningitis in the Asia–Pacific region