Monitoring environmental cleanliness on two surgical wards

Ten hand-touch sites were screened weekly on two surgical wards over two consecutive six-month periods. The results were analysed using hygiene standards, which specify 1) an aerobic colony count (ACC) >2.5cfu/cm2, and 2) presence of coagulase-positive staphylococci, as hygiene failures. Sites most often failing the standards were beds and hoist (64%: 33 of 52 weeks), bedside lockers (62%: 32 of 52) and overbed tables (44%: 23 of 52). Methicillin-susceptible/resistant Staphylococcus aureus (MSSA/MRSA) were more often recovered from lockers, overbed tables and beds. Recovery of MSSA/MRSA at any site was significantly associated with an ACC>2.5cfu/cm2 from that site (p=0.001; OR: 3.35 (95% CI 1.79, 6.28)). In addition, total ACC's>2.5cfu/cm2 each week were significantly associated with weekly bed occupancies >95% (p=0.0004; OR: 2.94 (95% CI 1.44, 6.02)). Higher microbial growth levels from hand-touch sites reflect weekly bed occupancies and indicate a risk for both resistant and susceptible S.aureus. These organisms are more likely to be recovered from near-patient sites on the ward

An improved Monte Carlo study of coherent scattering effects of low energy charged particle transport in Percus-Yevick liquids

We generalize a simple Monte Carlo (MC) model for dilute gases to consider the transport behavior of positrons and electrons in Percus-Yevick model liquids under highly non-equilibrium conditions, accounting rigorously for coherent scattering processes. The procedure extends an existing technique [Wojcik and Tachiya, Chem. Phys. Lett. 363, 3--4 (1992)], using the static structure factor to account for the altered anisotropy of coherent scattering in structured material. We identify the effects of the approximation used in the original method, and develop a modified method that does not require that approximation. We also present an enhanced MC technique that has been designed to improve the accuracy and flexibility of simulations in spatially-varying electric fields. All of the results are found to be in excellent agreement with an independent multi-term Boltzmann equation solution, providing benchmarks for future transport models in liquids and structured systems.Comment: 27 pages, 6 figure

Is silt the most influential soil grain size fraction?

The contribution of individual grain size fractions (2000–500, 500–250, 250–63, 63–2 and < 2 μm) to bulk soil surface area and reactivity is discussed with reference to mineralogical and oxalate and dithionite extractions data. The 63–2 μm fraction contributed up to 56% and 67% of bulk soil volume and BET surface area, respectively. Consideration of these observations and the mineralogy of this fraction suggest that the 63–2 μm fraction may be the most influential for the release of elements via mineral dissolution in the bulk soil

Comparison of primers for the detection of Phytophthora (and other oomycetes) from environmental samples

Many oomycetes are important plant pathogens that cause devastating diseases in agricultural fields, orchards, urban areas, and natural ecosystems. Limitations and difficulties associated with isolating these pathogens have led to a strong uptake of DNA metabarcoding and mass parallel sequencing. At least 21 primer combinations have been designed to amplify oomycetes, or more specifically, Phytophthora species, from environmental samples. We used the Illumina sequencing platform to compare 13 primer combinations on mock communities and environmental samples. The primer combinations tested varied significantly in their ability to amplify Phytophthora species in a mock community and from environmental samples; this was due to either low sensitivity (unable to detect species present in low concentrations) or a lack of specificity (an inability to amplify some species even if they were present in high concentrations). Primers designed for oomycetes underestimated the Phytophthora community compared to Phytophthora-specific primers. We recommend using technical replicates, primer combinations, internal controls, and a phylogenetic approach for assigning a species identity to OTUs or ASVs. Particular care must be taken if sampling substrates where hybrid species could be expected. Overall, the choice of primers should depend upon the hypothesis being tested

Subtypes in the autism spectrum: relating cognition to behaviour.

Three main theories have attempted to characterise autism at the cognitive level: theory of mind, executive function and central coherence but none are able to account for all the behavioural manifestations seen across different children. This thesis is concerned with heterogeneity within the autism spectrum that might exist at the cognitive level and how this relates to behaviour. 57 high-functioning 7-12 year olds with autism spectrum disorder (ASD) and 28 normally-developing children participated in tasks tapping into these three cognitive domains, as well as intelligence and head size. Their parents completed interviews concerning their behavioural symptoms. Support for the relevance of all three theories to ASD was found, with significant group differences between the ASD and control groups. Approximately 50% of the children with ASD displayed a detectable theory of mind impairment, 33% executive dysfunction and 20% weak central coherence, and all possible combinations of impairment were found. A further puzzling 40% of children displayed no detectable impairment, indicating either a misdiagnosis, that the tests were not sensitive enough, or that there was an additional cause not investigated here. Theory of mind and executive function abilities were found to be closely related, whilst central coherence was independent of these skills, indicating that at least two cognitive subtypes were present in the current sample. The emerging hypothesis was that theory of mind impairment adversely affected performance in unstructured executive function tests through a lack of understanding of implicit task demands. Only theory of mind and verbal ability were found to predict specific aspects of the behavioural triad. In addition, the presence of weak central coherence was related to the increased head size found in 20% of ASD cases, providing a possible endophenotype for this cognitive skill

Detecting copy number changes in genomic DNA - MAPH and MLPA

Humane en Klinische Genetica, LUMCAgilent Technologies, ZonMwGenoomkartering en moleculaire cytogenetic

Epigenetics Prematurely Born(e): Social Work and the Malleable Gene

Biological sciences are currently in the cultural ascent, promising to provide a theory of everything in the natural and social worlds. Beginning with the decade of the brain in the USA in the 1990s, neuroscience was first onto the stage, but developments in genomics, known as epigenetics have profound implications for society and culture, and the responses of the State to intimate family life and personal choices. Epigenetics provides an explanation of the mechanisms underpinning the interaction of the environment and the DNA blueprint, and thus invites an interest in the impact of adverse conditions, such as deprivation, or normatively deficient parenting. The implications of this biology of social disadvantage for social work are far reaching. Epigenetics is part of an increasingly political biology with the potential to affect the moral direction of social work. This paper reviews the state of the field and its immediate implications for the profession

Field-Driven Transitions in the Dipolar Pyrochlore Antiferromagnet Gd2_2Ti2_2O7_7

We present a mean-field theory for magnetic field driven transitions in dipolar coupled gadolinium titanate Gd$_2$Ti$_2$O$_7$ pyrochlore system. Low temperature neutron scattering yields a phase that can be regarded as a 8 sublattice antiferromagnet, in which long-ranged ordered moments and fluctuating moments coexist. Our theory gives parameter regions where such a phase is realized, and predicts several other phases, with transitions amongst them driven by magnetic field as well as temperature. We find several instances of {\em local} disorder parameters describing the transitions.Comment: 4 pages, 5 figures. v2: longer version with 2 add.fig., to appear in PR