Relative importance of herd-level risk factors for probability of infection with paratuberculosis in Irish dairy herds

Control of paratuberculosis is challenging due to the relatively poor performance of diagnostic tests, a prolonged incubation period, and protracted environmental survival. Prioritization of herd-level interventions is not possible because putative risk factors are often not supported by risk factor studies. The objective for this study was to investigate the relative importance of risk factors for an increased probability of herd paratuberculosis infection. Risk assessment data, comprehensive animal purchase history, and diagnostic test data were available for 936 Irish dairy herds. Both logistic regression and a Bayesian β regression on the outcome of a latent class analysis were conducted. Population attributable fractions and proportional reduction in variance explained were calculated for each variable in the logistic and Bayesian models, respectively. Routine use of the calving area for sick or lame cows was found to be a significant explanatory covariate in both models. Purchasing behavior for the previous 10 yr was not found to be significant. For the logistic model, length of time calves spend in the calving pen (25%) and routine use of the calving pen for sick or lame animals (14%) had the highest attributable fractions. For the Bayesian model, the overall R2 was 16%. Dry cow cleanliness (7%) and routine use of the calving area for sick or lame cows (6%) and had the highest proportional reduction in variance explained. These findings provide support for several management practices commonly recommended as part of paratuberculosis control programs; however, a large proportion of the observed variation in probability of infection remained unexplained, suggesting other important risks factors may exist

The identification of Staphylococcus aureus factors required for pathogenicity and growth in human blood

Staphylococcus aureus is a human commensal but also has devastating potential as an opportunist pathogen. S. aureus bacteraemia is often associated with an adverse outcome. To identify potential targets for novel control approaches we have identified S. aureus components that are required for growth on human blood. An ordered transposon mutant library was screened, identifying 9 genes involved specifically in haemolysis or growth on human blood agar compared to the parental strain. Three genes (purA, purB and pabA) were subsequently found to be required for pathogenesis in the zebrafish embryo infection model. The pabA growth defect was specific to the red blood cell component of human blood, showing no growth difference compared to the parental strain on human serum, human plasma, sheep or horse blood. PabA is required in the tetrahydrofolate (THF) biosynthesis pathway. The pabA growth defect was found to be due to a combination of loss of THF-dependent dTMP production by the enzyme ThyA and an increased demand for pyrimidines in human blood. Our work highlights pabA and the pyrimidine salvage pathway as potential targets for novel therapeutics and suggests a previously undefined role for a human blood factor in the activity of sulphonamide antibiotics

Caught in the middle: the role of the facilities manager in organisational energy use

This study analyses the role of the Facilities Manager [FM] as a key actor in organisational energy management. This builds on the idea that ‘middle’ agents in networks can be an important lever for socio-technical change. The study demonstrates the considerable impact the FM can have on workplace energy consumption, whilst identifying a number of factors that constrain their agency and capacity to act. These include demands to meet workforce expectations of comfort; a lack of support from senior management; and a shortage of resources. Underlying these challenges, the study identifies three different energy rationales – that is to say conceptual frameworks – which are deployed by different groups of organisational actors. The challenges of reconciling these at-times-contradictory rationales results in a picture of energy management which to the outsider can appear highly irrational. The paper concludes with a consideration of how policy makers can apply these insights to support energy reduction in workplaces

Free surface flows emerging from beneath a semi-infinite plate with constant vorticity

The free surface flow past a semi-infinite horizontal plate in a finite-depth fluid is considered. It is assumed that the fluid is incompressible and inviscid and that the flow approaches a uniform shear flow downstream. Exact relations are derived using conservation of mass and momentum for the case where the downstream free surface is flat. The complete nonlinear problem is solved numerically using a boundary integral method and these waveless solutions are shown to exist only when the height of the plate above the bottom is greater than the height of the uniform shear flow. Interesting results are found for various values of the constant vorticity. Solutions with downstream surface waves are also considered, and nonlinear results of this type are compared with linear results found previously. These solutions can be used to model the flow near the stern of a (two-dimensional) ship

Constitutivism

A brief explanation and overview of constitutivism

Precise Flow-Control Using Photo-Actuated Hydrogel Valves and Pid-controlled LED Actuation

Herein we demonstrate remarkable control of flow within fluidic channels using photo-actuated hydrogel valves. By polymerizing the valves in situ it has been possible to create highlyreproducible valves. Through the use of an LED platform and a PID algorithm we have generated extremely accurate flow control and created prototype devices to document their potential application within the microfluidics field

Precision control of flow rate in microfluidic channels using photoresponsive soft polymer actuators

A novel approach that allows control of flow in microfluidic channels with unsurpassed performance using light is described. Valve structures have been created using photoresponsive hydrogels based on spiropyran-functionalised pNIPAAm hydrogels photopolymerised around pillar structures within the channels. Valve actuation is controlled from outside the fluidic system using externally located LEDs. Highly precise and accurate flow rates can be selected by passing real-time flow rate measurements into a PID algorithm. The optimised algorithm also minimises overshoot of the selected flow rate, eliminates flow rate drift, and improves the system response time. In addition to the dramatic improvements in flow rate control, the set up enables the polymer actuation behaviour to be rapidly characterised. The power supply to the LED also provides a useful system diagnostic for monitoring the performance of the valve over time. For example, degradation in the valve actuation due to photodegradation will manifest as an increasing power requirement over time, enabling predictive failure thresholds to be established for particular actuator designs and polymer compositions

A direct physical interaction between Nanog and Sox2 regulates embryonic stem cell self-renewal

Embryonic stem (ES) cell self-renewal efficiency is determined by the Nanog protein level. However, the protein partners of Nanog that function to direct self-renewal are unclear. Here, we identify a Nanog interactome of over 130 proteins including transcription factors, chromatin modifying complexes, phosphorylation and ubiquitination enzymes, basal transcriptional machinery members, and RNA processing factors. Sox2 was identified as a robust interacting partner of Nanog. The purified Nanog–Sox2 complex identified a DNA recognition sequence present in multiple overlapping Nanog/Sox2 ChIP-Seq data sets. The Nanog tryptophan repeat region is necessary and sufficient for interaction with Sox2, with tryptophan residues required. In Sox2, tyrosine to alanine mutations within a triple-repeat motif (S X T/S Y) abrogates the Nanog–Sox2 interaction, alters expression of genes associated with the Nanog-Sox2 cognate sequence, and reduces the ability of Sox2 to rescue ES cell differentiation induced by endogenous Sox2 deletion. Substitution of the tyrosines with phenylalanine rescues both the Sox2–Nanog interaction and efficient self-renewal. These results suggest that aromatic stacking of Nanog tryptophans and Sox2 tyrosines mediates an interaction central to ES cell self-renewal

An Exploratory Investigation of Traditional Scoring in Diving and Relationships to the Development of Artificial Intelligence Opportunities

This study investigated the conceptions of perfection that figure in the minds of divers, coaches, and judges. Additionally, consideration was given to their views of whether an Artificial Intelligence (AI) based scoring system could be relied upon to yield authentic results, allied with the desirability of its use. Six participants (2 each of diver, coach, judge) were interviewed. Following verbatim transcriptions, thematic analyses were conducted to identify commonly occurring themes relevant to diving and its scoring system. The results of this preliminary study have shown a leaning towards clarification of the rules on point deductions by FINA (Fédération Internationale De Natation/ International Swimming Federation). Furthermore, the concept of perfection in diving changes from country to country and culture to culture, providing further difficulties in the objectivity of judging and there was a call for openness and clarity. With the human element of judging carrying weakness and allowing for errors, subsequently, it was felt by the respondents that some parts of a dive should be measured with technology where feasible. There was a consensus that judges could not be fully replaced without substantive changes to the sport of diving, in effect losing the artistic element that is subjectively assessed