The Spread of Bluetongue Virus Serotype 8 in Great Britain and Its Control by Vaccination

Bluetongue (BT) is a viral disease of ruminants transmitted by Culicoides biting midges and has the ability to spread rapidly over large distances. In the summer of 2006, BTV serotype 8 (BTV-8) emerged for the first time in northern Europe, resulting in over 2000 infected farms by the end of the year. The virus subsequently overwintered and has since spread across much of Europe, causing tens of thousands of livestock deaths. In August 2007, BTV-8 reached Great Britain (GB), threatening the large and valuable livestock industry. A voluntary vaccination scheme was launched in GB in May 2008 and, in contrast with elsewhere in Europe, there were no reported cases in GB during 2008.Here, we use carefully parameterised mathematical models to investigate the spread of BTV in GB and its control by vaccination. In the absence of vaccination, the model predicted severe outbreaks of BTV, particularly for warmer temperatures. Vaccination was predicted to reduce the severity of epidemics, with the greatest reduction achieved for high levels (95%) of vaccine uptake. However, even at this level of uptake the model predicted some spread of BTV. The sensitivity of the predictions to vaccination parameters (time to full protection in cattle, vaccine efficacy), the shape of the transmission kernel and temperature dependence in the transmission of BTV between farms was assessed.A combination of lower temperatures and high levels of vaccine uptake (>80%) in the previously-affected areas are likely to be the major contributing factors in the control achieved in England in 2008. However, low levels of vaccination against BTV-8 or the introduction of other serotypes could result in further, potentially severe outbreaks in future

Optical phonons, OH vibrations, and structural modifications of phlogopite at high temperatures: An in-situ infrared spectroscopic study

The thermal behavior of optical phonons and OH vibrations of phlogopite (a trioctahedral mica) was examined at temperatures up to 1000 K using in situ infrared spectroscopy. The results showed that with increasing temperature, O–K bands in phlogopite exhibited a relatively strong variation in frequency in a manner similar to those in muscovite. The work revealed that different types of OH bands (fundamentals and combinations) have very different thermal behavior or temperature dependence, and their absorption coefficients are commonly not constant on heating. OH combination bands that are associated with summation processes of multi-phonon interactions commonly show a decrease in their intensities on heating, but in contrast combination bands due to difference processes generally exhibit an increase. This means that temperature dependencies of their absorption coefficients need to be considered when using the Beer-Lambert law to determine or estimate OH contents or hydrogen concentrations at high temperatures. The results showed a structural anomaly associated with a discontinuity in the temperature derivative of the wavenumber of Al–O and Si–O vibrations and O–H stretching near 600 K. However, framework-related phonon modes in the FIR and MIR regions do not suggest a break of the original monoclinic structural symmetry in the investigated temperature region. The complex changes are attributed to temperature-induced alteration of local configuration involving TO4 tetrahedra and a possible change of the orientation of OH dipoles, in addition to a previously reported distortion of MO6 octahedra. Increasing temperature to 1000 K also causes partial dehydroxylation, as evidenced by the disappearance of the OH band near 3623 cm−1 and the decrease in OH band height and area of other OH bands. The study did not record the formation of H2O inside phlogopite as a result of partial dehydroxylation. The work offers new data and findings that have important implications in understanding the complex structural modifications and the behavior of phonon modes and the thermal stability of hydroxyls on approaching the dehydroxylation, as well as the way hydrogen is released from micas at high temperatures. Our data also show that phologpite becomes less transparent with increasing temperature suggesting a change of radiative properties and ability to transmit heat, which could be of interest for modeling thermal-transmission in crustal rocks

Integrating numerical cognition research and mathematics education to strengthen the teaching and learning of early number

BACKGROUND: Research into numerical cognition has contributed to a large body of knowledge on how children learn and perform mathematics. This knowledge has the potential to inform mathematics education. Unfortunately, numerical cognition research and mathematics education remain disconnected from one another, lacking the proper infrastructure to allow for productive and meaningful exchange between disciplines. The present study was designed to address this gap. AIM: This study reports on the design, implementation, and effects of a 16-week (25-hour) mathematics Professional Development (PD) model for Kindergarten to Grade 3 educators and their students. A central goal of the PD was to better integrate numerical cognition research and mathematics education. SAMPLE: A total of 45 K-3 educators and 180 of their students participated. METHODS: To test the reproducibility and replicability of the model, the study was carried out across two different sites, over a two-year period, and involved a combination of two different study designs: a quasi-experimental pre-post-research design and a within-group crossover intervention design. RESULT: The results of the first implementation (Year 1), indicated that compared to a control group, both teachers and students benefited from the intervention. Teachers demonstrated gains on both a self-report measure and a test of numerical cognition knowledge, while students demonstrated gains in number line estimation, arithmetic, and numeration. In Year 2, teachers in the intervention group demonstrated greater improvements than the control group on the self-report measure, but not the test of numerical cognition knowledge. At the student level, there was some evidence of gains in numeration. CONCLUSION: The current PD model is a promising approach to better integrate research and practice. However, more research is needed to determine in which school contexts the model is most effective

The Importance of Audit Firm Characteristics and the Drivers of Auditor Change in UK Listed Companies

This paper explores the importance of audit firm characteristics and the factors motivating auditor change based on questionnaire responses from 210 listed UK companies (a response rate of 70%). Twenty-nine potentially desirable auditor characteristics are identified from the extant literature and their importance elicited. Exploratory factor analysis reduces these variables to eight uncorrelated underlying dimensions: reputation/quality; acceptability to third parties; value for money; ability to provide non-audit services; small audit firm; specialist industry knowledge; non-Big Six large audit firm; and geographical proximity. Insights into the nature of 'the Big Six factor' emerge. Two thirds of companies had recently considered changing auditors; the main reasons cited being audit fee level, dissatisfaction with audit quality and changes in top management. Of those companies that considered change, 73% did not actually do so, the main reasons cited being fee reduction by the incumbent and avoidance of disruption. Thus audit fee levels are both a key precipitator of change and a key factor in retaining the status quo

Optical phonons, OH vibrations, and structural modifications of phlogopite at high temperatures: An in-situ infrared spectroscopic study

The thermal behavior of optical phonons and OH vibrations of phlogopite (a trioctahedral mica) was examined at temperatures up to 1000 K using in situ infrared spectroscopy. The results showed that with increasing temperature, O–K bands in phlogopite exhibited a relatively strong variation in frequency in a manner similar to those in muscovite. The work revealed that different types of OH bands (fundamentals and combinations) have very different thermal behavior or temperature dependence, and their absorption coefficients are commonly not constant on heating. OH combination bands that are associated with summation processes of multi-phonon interactions commonly show a decrease in their intensities on heating, but in contrast combination bands due to difference processes generally exhibit an increase. This means that temperature dependencies of their absorption coefficients need to be considered when using the Beer-Lambert law to determine or estimate OH contents or hydrogen concentrations at high temperatures. The results showed a structural anomaly associated with a discontinuity in the temperature derivative of the wavenumber of Al–O and Si–O vibrations and O–H stretching near 600 K. However, framework-related phonon modes in the FIR and MIR regions do not suggest a break of the original monoclinic structural symmetry in the investigated temperature region. The complex changes are attributed to temperature-induced alteration of local configuration involving TO4 tetrahedra and a possible change of the orientation of OH dipoles, in addition to a previously reported distortion of MO6 octahedra. Increasing temperature to 1000 K also causes partial dehydroxylation, as evidenced by the disappearance of the OH band near 3623 cm−1 and the decrease in OH band height and area of other OH bands. The study did not record the formation of H2O inside phlogopite as a result of partial dehydroxylation. The work offers new data and findings that have important implications in understanding the complex structural modifications and the behavior of phonon modes and the thermal stability of hydroxyls on approaching the dehydroxylation, as well as the way hydrogen is released from micas at high temperatures. Our data also show that phologpite becomes less transparent with increasing temperature suggesting a change of radiative properties and ability to transmit heat, which could be of interest for modeling thermal-transmission in crustal rocks

Drinking Water Supply, Sanitation, and Hygiene Promotion Interventions in Two Slum Communities in Central Uganda

Poor water, sanitation, and hygiene (WASH) continue to contribute to the high prevalence of diarrhoeal diseases in low-income countries such as Uganda particularly in slums. We implemented a 3-year WASH project in two urban slums in Uganda with a focus on safe drinking water and improvement in sanitation. The project implemented community and school interventions in addition to capacity building initiatives. Community interventions included home improvement campaigns, clean-up exercises, water quality assessment, promotion of drinking safe water through household point-of-use chlorination, promotion of hand washing, and support towards solid waste management. In schools, the project supported health clubs and provided them with “talking compound” messages. The capacity building initiatives undertaken included training of youth and community health workers. Project evaluation revealed several improvements in WASH status of the slums including increase in piped water usage from 38% to 86%, reduction in use of unprotected water sources from 30% to 2%, reduction in indiscriminate disposal of solid waste from 18% to 2%, and increase in satisfaction with solid waste management services from 40% to 92%. Such proactive and sustainable community interventions have the potential to not only improve lives of slum inhabitants in developing countries but also create lasting impact

Large dust particles in disks around T Tauri stars

We present 7-mm continuum observations of 14 low-mass pre-main-sequence stars in the Taurus-Auriga star-forming region obtained with the Very Large Array with ~1.5" resolution and ~0.3 mJy rms sensitivity. For 10 objects, the circumstellar emission has been spatially resolved. The large outer disk radii derived suggest that the emission at this wavelength is mostly optically thin. The millimetre spectral energy distributions are characterised by spectral indices alpha = 2.3 to 3.2. After accounting for contribution from free-free emission and corrections for optical depth, we determine dust opacity indices beta in the range 0.5 to 1.6, which suggest that millimetre-sized dust aggregates are present in the circumstellar disks. Four of the sources with beta > 1 may be consistent with submicron-sized dust as found in the interstellar medium. Our findings indicate that dust grain growth to millimetre-sized particles is completed within less than 1 Myr for the majority of circumstellar disks.Comment: 11 pages, 4 figure

An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students

<p>Aims: This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology.</p> <p>Methods: Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C.</p> <p>Results: A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not.</p> <p>Conclusions: Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination.</p&gt