The epidemiology of infectious mononucleosis in Northern Scotland : a decreasing incidence and winter peak

Peer reviewedPublisher PD

Investigating the regional variation in rules and best management practices for forestry in New Zealand

Under the Resource Management Act 1991 (NZ), the interpretation and implementation of environmental policy is primarily the responsibility of local government. The management of forestry operations may be influenced by statutory rules published in regional and district plans, and recommended best management practices (BMPs) published in guidelines. There are concerns that inconsistency between jurisdictions’ rules have a negative impact on the forestry industry’s financial and environmental outcomes. This research investigated and quantified the variation in Permitted Activity rules and BMPs, for culvert installation and earthworks, between New Zealand’s 16 Regional Councils. Significant variation in these regional rules and BMPs existed in both the level of control (i.e., the number of rules and BMPs per council), and the nature of control (i.e., the proportion of rules or BMPs utilised). Further, the rules and BMPs of one council are seldom the same as another. This variation is apparent on both a national scale and when considering only neighbouring pairs of councils

Mutation supply and the repeatability of selection for antibiotic resistance

Whether evolution can be predicted is a key question in evolutionary biology. Here we set out to better understand the repeatability of evolution. We explored experimentally the effect of mutation supply and the strength of selective pressure on the repeatability of selection from standing genetic variation. Different sizes of mutant libraries of an antibiotic resistance gene, TEM-1 $\beta$-lactamase in Escherichia coli, were subjected to different antibiotic concentrations. We determined whether populations went extinct or survived, and sequenced the TEM gene of the surviving populations. The distribution of mutations per allele in our mutant libraries- generated by error-prone PCR- followed a Poisson distribution. Extinction patterns could be explained by a simple stochastic model that assumed the sampling of beneficial mutations was key for survival. In most surviving populations, alleles containing at least one known large-effect beneficial mutation were present. These genotype data also support a model which only invokes sampling effects to describe the occurrence of alleles containing large-effect driver mutations. Hence, evolution is largely predictable given cursory knowledge of mutational fitness effects, the mutation rate and population size. There were no clear trends in the repeatability of selected mutants when we considered all mutations present. However, when only known large-effect mutations were considered, the outcome of selection is less repeatable for large libraries, in contrast to expectations. Furthermore, we show experimentally that alleles carrying multiple mutations selected from large libraries confer higher resistance levels relative to alleles with only a known large-effect mutation, suggesting that the scarcity of high-resistance alleles carrying multiple mutations may contribute to the decrease in repeatability at large library sizes.Comment: 31pages, 9 figure

Interaction between counter-propagating quantum Hall edge channels in the 3D topological insulator BiSbTeSe2_2

The quantum Hall effect is studied in the topological insulator BiSbTeSe$_2$. By employing top- and back-gate electric fields at high magnetic field, the Landau levels of the Dirac cones in the top and bottom topological surface states can be tuned independently. When one surface is tuned to the electron-doped side of the Dirac cone and the other surface to the hole-doped side, the quantum Hall edge channels are counter-propagating. The opposite edge mode direction, combined with the opposite helicities of top and bottom surfaces, allows for scattering between these counter-propagating edge modes. The total Hall conductance is integer valued only when the scattering is strong. For weaker interaction, a non-integer quantum Hall effect is expected and measured

Shadow TUAV Single Operator Consolidation : Display Assessment

Currently, Shadow UAV operations require two people: the Air Vehicle Operator (AVO) and the Mission Payload Operator (MPO). A previous workload study demonstrated that it is possible to combine these two positions such that one person can assume both roles (Appendix A). However, to achieve this consolidation, improved displays in terms of usability and increased automated functionality will be necessary to keep the workload of the single operator to acceptable levels. To demonstrate the types of changes that will need to occur for successful AVO and MPO consolidation, this report focuses on display and automation improvements in the following three areas: systems management, vehicle situation awareness, and payload operations. For each of these areas, a previous display has either been designed or improved upon, always applying human factors design principles. Each of these display redesigns exemplifies how operator workload can be decreased, as well as improve overall mission capability

Season of infectious mononucleosis as a risk factor for multiple sclerosis : a UK primary care case-control study

This study is based in part on data from the Full Feature General Practice Research Database obtained under licence from the UK Medicines and Healthcare Products Regulatory Agency. However, the interpretation and conclusions contained in this study are those of the authors alone. Access to the GPRD database was funded through the Medical Research Council’s licence agreement with MHRA. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. We acknowledge the data management support of the Grampian Data Safe Haven (DaSH) and the associated financial support of NHS Research Scotland through NHS Grampian investment in the Grampian DaSH.Peer reviewedPostprintPostprintPostprin

The association between muscle strength and activity limitations in patients with the hypermobility type of Ehlers–Danlos syndrome : the impact of proprioception

Purpose: The patients diagnosed with Ehlers-Danlos Syndrome Hypermobility Type (EDS-HT) are characterized by pain, proprioceptive inacuity, muscle weakness, potentially leading to activity limitations. In EDS-HT, a direct relationship between muscle strength, proprioception and activity limitations has never been studied. The objective of the study was to establish the association between muscle strength and activity limitations and the impact of proprioception on this association in EDS-HT patients. Methods: Twenty-four EDS-HT patients were compared with 24 controls. Activity limitations were quantified by Health Assessment Questionnaire (HAQ), Six-Minute Walk test (6MWT) and 30-s chair-rise test (30CRT). Muscle strength was quantified by handheld dynamometry. Proprioception was quantified by movement detection paradigm. In analyses, the association between muscle strength and activity limitations was controlled for proprioception and confounders. Results: Muscle strength was associated with 30CRT (r = 0.67, p = <0.001), 6MWT (r = 0.58, p = <0.001) and HAQ (r = 0.63, p = <0.001). Proprioception was associated with 30CRT (r = 0.55, p <0.001), 6MWT (r = 0.40, p = <0.05) and HAQ (r = 0.46, p < 0.05). Muscle strength was found to be associated with activity limitations, however, proprioceptive inacuity confounded this association. Conclusions: Muscle strength is associated with activity limitations in EDS-HT patients. Joint proprioception is of influence on this association and should be considered in the development of new treatment strategies for patients with EDS-HT. Implications for rehabilitation : Reducing activity limitations by enhancing muscle strength is frequently applied in the treatment of EDS-HT patients. Although evidence regarding treatment efficacy is scarce, the current paper confirms the rationality that muscle strength is an important factor in the occurrence of activity limitations in EDS-HT patients. Although muscle strength is the most dominant factor that is associated with activity limitations, this association is confounded by proprioception. In contrast to common belief proprioception was not directly associated with activity limitations but confounded this association. Controlling muscle strength on the bases of proprioceptive input may be more important for reducing activity limitations than just enhancing sheer muscle strength

NPSHR (NPSH3) IMPROVEMENT OF A LOW PRESSURE SAFETY INJECTION PUMP

Case StudiesThis case study discusses the rerate of a set of vertically-mounted singlestage end-suction centrifugal pumps used for low pressure safety injection (LPSI) in a nuclear power plant. The original LPSI pumps were supplied early 1970’s and for safety purposes it was decided to overhaul these pumps to improve NPSHR (i.e. NPSH3). The rerate consisted of replacing the existing impeller with a new design yielding close to identical head performance characteristic, yet better NPSHR. Aim was to improve NPSHR by (minimally) 0.5 m (1.64 ft) at rated capacity of 682 m3 /h (3003 USGPM) and 1470 r/min running speed, and demonstrate by test the actual improvement in NPSHR