Variable changes in nematode infection prevalence and intensity after Rabbit Haemorrhagic Disease Virus emerged in wild rabbits in Scotland and New Zealand

The myxoma virus (a microparasite) reduced wild rabbit numbers worldwide when introduced in the 1950s, and is known to interact with co-infecting helminths (macroparasites) causing both increases and decreases in macroparasite population size. In the 1990s Rabbit Haemorrhagic Disease Virus (RHDV) infected rabbits and also significantly reduced rabbit numbers in several countries. However, not much is known about RHDV interactions with macroparasites. In this study, we compare prevalence and intensity of infection for three gastrointestinal nematode species (Trichostrongylus retortaeformis, Graphidium strigosum and Passalurus ambiguus) before and after RHDV spread across host populations in Scotland and New Zealand. During one common season, autumn, prevalence of T. retortaeformis was higher after RHDV spread in both locations, whereas it was lower for G. strigosum and P. ambiguus after RHDV arrived in New Zealand, but higher in Scotland. Meanwhile, intensity of infection for all species decreased after RHDV arrived in New Zealand, but increased in Scotland. The impact of RHDV on worm infections was generally similar across seasons in Scotland, and also similarities in seasonality between locations suggested effects on infection patterns in one season are likely similar year-round. The variable response by macroparasites to the arrival of a microparasite into Scottish and New Zealand rabbits may be due to differences in the environment they inhabit, in existing parasite community structure, and to some extent, in the relative magnitude of indirect effects. Specifically, our data suggest that bottom-up processes after the introduction of a more virulent strain of RHDV to New Zealand may affect macroparasite co-infections by reducing the availability of their shared common resource, the rabbits. Clearly, interactions between co-infecting micro- and macroparasites vary in host populations with different ecologies, and significantly impact parasite community structure in wildlife. Keywords: Co-infection, Community ecology, European rabbit, Helminth, Macroparasite, Microparasite, RHDV, Virus, Within-host ecolog

Direct Detection of the Close Companion of Polaris with the Hubble Space Telescope

Polaris, the nearest and brightest classical Cepheid, is a single-lined spectroscopic binary with an orbital period of 30 years. Using the High Resolution Channel of the Advanced Camera for Surveys onboard the Hubble Space Telescope (HST) at a wavelength of ~2255\AA, we have directly detected the faint companion at a separation of 0\farcs17. A second HST observation 1.04 yr later confirms orbital motion in a retrograde direction. By combining our two measures with the spectroscopic orbit of Kamper and an analysis of the Hipparcos and FK5 proper motions by Wielen et al., we find a mass for Polaris Aa of 4.5^{+2.2}_{-1.4} M_\odot--the first purely dynamical mass determined for any Cepheid. For the faint companion Polaris Ab we find a dynamical mass of 1.26^{+0.14}_{-0.07} M_\odot, consistent with an inferred spectral type of F6 V and with the flux difference of 5.4 mag observed at 2255\AA. The magnitude difference at the V band is estimated to be 7.2 mag. Continued HST observations will significantly reduce the mass errors, which are presently still too large to provide critical constraints on the roles of convective overshoot, mass loss, rotation, and opacities in the evolution of intermediate-mass stars. Our astrometry, combined with two centuries of archival measurements, also confirms that the well-known, more distant (18") visual companion, Polaris B, has a nearly common proper motion with that of the Aa,Ab pair. This is consistent with orbital motion in a long-period bound system. The ultraviolet brightness of Polaris B is in accordance with its known F3 V spectral type if it has the same distance as Polaris Aa,Ab.Comment: 31 pages, 12 figures, 6 tables; accepted for publication in the Astronomical Journa

Graphene-Based Transparent Flexible Strain Gauges with Tunable Sensitivity and Strain Range

Flexible strain gauges with 88% optical transmittance, of reduced graphene oxide (rGO) on poly dimethylsiloxne membranes, are produced form monolayers of graphene oxide assembled into densely packed sheets at an immiscible hexane/water interface and subsequently reduced in HI vapor to increase electrical conductivity. Pre-straining and relaxing the membranes introduces a population of cracks into the rGO film. Subsequent straining opens these cracks, inducing piezoresistivity. Reduction for 30 s forms an array of parallel cracks that do not individually span the membrane and results in a strain gauge with a usable strain range > 0.2 and gauge factor of 20 - 100 at low strain levels that increases with increasing pre-strain. In all cases the gauge facto decreases with increasing applied strain and asymptotes to a value of about 3, as it approaches the pre-strain value. If the rGO is reduced for 60 s, the cracks fully span the width of the membrane, leading to an increased gauge resistance but a much more sensitive strain gauge with GF ranging from 1000 - 16000. However, the usable strain range reduces to < 0.01. A simple equivalent resistor model is proposed to describe the behaviour of both gauge types. The gauges show a repeatable and stable response with loading frequencies up to 1 kHz and have been used to detect human body motion in a simple e-skin demonstration.Comment: 24 Pages, 9 Figures plus Supporting Information 11 page

Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska

Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater and marine habitats including lacustrine, riverine, estuarine, and marine. Forty-five whitefish were tagged with radio transmitters in 2006 and 2007, and another 29 whitefish were tagged with acoustic tags in 2008. In addition, otolith chemistry was used to evaluate marine habitat use of humpback whitefish sampled from McKinley Lake in the Copper River Delta, Alaska. Movements and migration of tagged fish were tracked using biotelemetry techniques from boats, airplanes, and fixed receiver stations throughout the spring, summer, and fall. Sagittal otoliths were extracted from 20 humpback whitefish and a chemical analysis was performed to evaluate levels of Sr:Ca. Biotelemetry and sampling results revealed seasonal migrations where humpback whitefish migrated into McKinley Lake in mid to late spring and left the lake by late summer and early fall. Fish migrated to the Copper River in the fall by traveling down Alaganik Slough and then to the Copper River by traveling through Pete Dahl Cutoff Slough or the Gulf of Alaska. Fish travel up the Copper River presumably to their spawning grounds. Nine tagged fish returned to McKinley Lake in 2007 and four tagged fish in 2008, indicating some fidelity to the summer feeding site. Otolith chemistry detected marine migrations in 45% of the samples. Three migratory behaviors were observed, while some individuals inhabited only freshwater environments, some individuals made single migrations to marine habitats, and other individuals made multiple migrations to marine habitats. Age of whitefish ranged from 2 to 9 years. Analysis of small-scale movement of humpback whitefish in McKinley Lake found movement rates to be significantly higher at dusk compared to night in one sampling period. However, diel movement activity in all other diel periods did not significantly differ, suggesting arrhythmic diel movement. A large portion of the lake was occupied at any given time, but not all areas were used equally. Activity levels, measured by change in zones, were variable between dates and indicated that fish often moved between detection zones. An increase in activity was observed in individuals 48 h prior to migration from the lake. This study provides the first documentation of migration, movement, and habitat use of humpback whitefish in the Copper River Delta, Alaska. Results of this study will help inform management of humpback whitefish in order to sustain populations into the future. This information should be considered in land use and species management planning in the Copper River basin including fish passage and harvest regulations

Non-destructive identification of fibre orientation in multi-ply biaxial laminates using contact temperature sensors

Fibre orientation within composite structures dictates the material properties of the laminate once cured. The ability to accurately and automatically assess fibre orientation of composite parts is a significant enabler in the goal to optimise the established processes within aftermarket aerospace industries. Incorrect ply lay-up results in a structure with undesirable material properties and as such, has the potential to fail under safe working loads. Since it is necessary to assure structural integrity during re-manufacture and repair assessment, the paper demonstrates a novel method of readily and non-destructively determining fibre orientation throughout multi-ply Biaxial woven composite laminates using point temperature contact sensors and data analysis techniques. Once cured, only the outermost laminates are visible to assess orientation. The inspection method is conducted visually, with reference guides to allow for rapid adoption with minimum training, as well as harnessing established temperature sensors within the Maintenance Repair and Overhaul (MRO) environment. The system is amenable to integration within existing repair/re-manufacture processes without significant impact to process flow. The method is able to identify noisy samples with an accuracy, precision and recall of 0.9, and for synthetically created samples of double the cure ply thickness, a precision of 0.75, a recall of 0.7 and an accuracy of 0.87

Herbivore biocontrol and manual removal successfully reduce invasive macroalgae on coral reefs

Invasive macroalgae pose a serious threat to coral reef biodiversity by monopolizing reef habitats, competing with native species, and directly overgrowing, and smothering reef corals. Several invasive macroalgae (Eucheuma clade E, Kappaphycus clade A and B, Gracilaria salicornia, and Acanthophora spicifera) are established within Kāne‘ohe Bay (O‘ahu, Hawai‘i, USA), and reducing invasive macroalgae cover is a coral reef conservation and management priority. Invasive macroalgae control techniques, however, are limited and few successful large-scale applications exist. Therefore, a two-tiered invasive macroalgae control approach was designed, where first, divers manually remove invasive macroalgae (Eucheuma and Kappaphycus) aided by an underwater vacuum system (“The Super Sucker”). Second, hatchery-raised juvenile sea urchins (Tripneustes gratilla), were outplanted to graze and control invasive macroalgae regrowth. To test the effectiveness of this approach in a natural reef ecosystem, four discrete patch reefs with high invasive macroalgae cover (15–26%) were selected, and macroalgae removal plus urchin biocontrol (treatment reefs, n = 2), or no treatment (control reefs, n = 2), was applied at the patch reef-scale. In applying the invasive macroalgae treatment, the control effort manually removed ∼19,000 kg of invasive macroalgae and ∼99,000 juvenile sea urchins were outplanted across to two patch reefs, totaling ∼24,000 m2 of reef area. Changes in benthic cover were monitored over 2 years (five sampling periods) before-and-after the treatment was applied. Over the study period, removal and biocontrol reduced invasive macroalgae cover by 85% at treatment reefs. Our results show manual removal in combination with hatchery raised urchin biocontrol to be an effective management approach in controlling invasive macroalgae at reef-wide spatial scales and temporal scales of months to years

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Geometrical thermal analysis as a form of Finite Element Analysis enhancement

Maintenance Repair and Overhaul (MRO) of composite aerospace components requires rigorous stress and strain analysis, including mechanical and thermal, as part of the repair process. Finite Element Analysis (FEA) as a standard and robust method of determining the transfer of transient thermal results of materials is well established for remanufacture. However, the theoretical material properties upon which FEA models are based often do not correspond to real life composite aerospace parts, due to manufacturing variations and the addition of previous repairs to the component modifying the fibre orientation and local fibre volume fraction. Such deviations from FEA models can result in inadequate repairs and in extreme instances even cause thermal damage to components. A geometrical analysis method incorporating existing industry standard heating elements and single point thermal capture sensors (i.e. Resistance Temperature Detectors or Thermocouples) using captured data could be used to quickly verify transient thermal results and provide useful data in order to correct the FEA model