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Efforts to prioritize wildlife for conservation benefit from an understanding of public preferences for particular species, yet no studies have integrated species preferences with key attributes of the conservation landscape such as whether species occur on islands (where invasive exotics are the primary extinction threat) or continents (where land use change is the primary extinction threat). In this paper, we compare wildlife species preferences among children from a continental location (North Carolina, USA, n = 433) and an island location (Andros Island, The Bahamas, n = 197). Children on the island preferred feral domesticated species and different types of taxa than mainland children, perhaps due to the strongly divergent species richness between the regions (e.g. island children showed greater preferences for invertebrates, lizards and aquatic species). Boys preferred fish, birds and lizards more than girls, whereas girls preferred mammals. The fact that island children showed strong preferences for invasive species suggests challenges for conservation efforts on islands, where controlling invasive exotic species is often of paramount importance, but can conflict with cultural preferences for these same species.
The Cycadales are a group of significant global conservation concern and have the highest extinction risk of all seed plants. Understanding the synchronisation of reproductive phenology of Cycadales may be useful for conservation by enabling the targeting of pollen and seed collection from wild populations and identifying the window of fertilisation to aid in the cultivation of Cycadales. Phenological data for 11 species of Zamia were gathered from herbarium specimens. Four phenological characters were coded with monthly character states. DNA was isolated and sequenced for 26S, CAB, NEEDLY, matK and rbcL, and a simultaneous phylogenetic analysis of phenology and DNA sequence data was carried out. Three major clades were recovered: a Caribbean clade, a Central American clade and a South American clade. Eight species showed statistically significant synchronisation in microsporangiate and ovulate phenological phases, indicating the time of fertilisation. Close reproductive synchronisation was consistently observed throughout the Caribbean clade (statistically significant in four of five species) but was less consistent in the Central American clade (statistically significant in one of two species) and South American clade (statistically significant in three of four species). Ultimately, phenology is shown to be a potential driver of speciation in some clades of Zamia and in others to be a potential barrier to hybridisation.
In late 2011 the New Zealand Ministry for Primary Industries reported an increase in confirmed laboratory diagnoses of salmonellosis in dairy herds. To identify risk factors for herd-level outbreaks of salmonellosis we conducted a case-control study of New Zealand dairy herds in 2011–2012. In a multivariable analysis, use of continuous feed troughs [adjusted odds ratio (aOR) 6·2, 95% confidence interval (CI) 2·0–20], use of pelletized magnesium supplements (aOR 10, 95% CI 3·3–33) and use of palm kernel meal as a supplementary feed (aOR 8·7, 95% CI 2·5–30) were positively associated with a herd-level outbreak of salmonellosis between 1 July 2011 and 31 January 2012. We conclude that supplementary feeds used on dairy farms (regardless of type) need to be stored and handled appropriately to reduce the likelihood of bacterial contamination, particularly from birds and rodents. Magnesium supplementation in the pelletized form played a role in triggering outbreaks of acute salmonellosis in New Zealand dairy herds in 2011–2012.
A scalable approach for synthesis of ultra-thin (<10 nm) transition metal dichalcogenides (TMD) films on stretchable polymeric materials is presented. Specifically, magnetron sputtering from pure TMD targets, such as MoS2 and WS2, was used for growth of amorphous precursor films at room temperature on polydimethylsiloxane substrates. Stacks of different TMD films were grown upon each other and integrated with optically transparent insulating layers such as boron nitride. These precursor films were subsequently laser annealed to form high quality, few-layer crystalline TMDs. This combination of sputtering and laser annealing is commercially scalable and lends itself well to patterning. Analysis by Raman spectroscopy, scanning probe, optical, and transmission electron microscopy, and x-ray photoelectron spectroscopy confirm our assertions and illustrate annealing mechanisms. Electrical properties of simple devices built on flexible substrates are correlated to annealing processes. This new approach is a significant step toward commercial-scale stretchable 2D heterostructured nanoelectronic devices.
Simulation models can offer valuable insights into the effectiveness of different control strategies and act as important decision support tools when comparing and evaluating outbreak scenarios and control strategies. An international modelling study was performed to compare a range of vaccination strategies in the control of foot-and-mouth disease (FMD). Modelling groups from five countries (Australia, New Zealand, USA, UK, The Netherlands) participated in the study. Vaccination is increasingly being recognized as a potentially important tool in the control of FMD, although there is considerable uncertainty as to how and when it should be used. We sought to compare model outputs and assess the effectiveness of different vaccination strategies in the control of FMD. Using a standardized outbreak scenario based on data from an FMD exercise in the UK in 2010, the study showed general agreement between respective models in terms of the effectiveness of vaccination. Under the scenario assumptions, all models demonstrated that vaccination with ‘stamping-out’ of infected premises led to a significant reduction in predicted epidemic size and duration compared to the ‘stamping-out’ strategy alone. For all models there were advantages in vaccinating cattle-only rather than all species, using 3-km vaccination rings immediately around infected premises, and starting vaccination earlier in the control programme. This study has shown that certain vaccination strategies are robust even to substantial differences in model configurations. This result should increase end-user confidence in conclusions drawn from model outputs. These results can be used to support and develop effective policies for FMD control.
The Parkes pulsar data archive currently provides access to 144044 data files obtained from observations carried out at the Parkes observatory since the year 1991. Around 105 files are from surveys of the sky, the remainder are observations of 775 individual pulsars and their corresponding calibration signals. Survey observations are included from the Parkes 70 cm and the Swinburne Intermediate Latitude surveys. Individual pulsar observations are included from young pulsar timing projects, the Parkes Pulsar Timing Array and from the PULSE@Parkes outreach program. The data files and access methods are compatible with Virtual Observatory protocols. This paper describes the data currently stored in the archive and presents ways in which these data can be searched and downloaded.
Proton radiography using laser-driven sources has been developed as a diagnostic since the beginning of the decade, and applied successfully to a range of experimental situations. Multi-MeV protons driven from thin foils via the Target Normal Sheath Acceleration mechanism, offer, under optimal conditions, the possibility of probing laser-plasma interactions, and detecting electric and magnetic fields as well as plasma density gradients with ~ps temporal resolution and ~ 5–10 µm spatial resolution. In view of these advantages, the use of proton radiography as a diagnostic in experiments of relevance to Inertial Confinement Fusion is currently considered in the main fusion laboratories. This paper will discuss recent advances in the application of laser-driven radiography to experiments of relevance to Inertial Confinement Fusion. In particular we will discuss radiography of hohlraum and gasbag targets following the interaction of intense ns pulses. These experiments were carried out at the HELEN laser facility at AWE (UK), and proved the suitability of this diagnostic for studying, with unprecedented detail, laser-plasma interaction mechanisms of high relevance to Inertial Confinement Fusion. Non-linear solitary structures of relevance to space physics, namely phase space electron holes, have also been highlighted by the measurements. These measurements are discussed and compared to existing models.
Limitations of access have long restricted exploration and investigation of the cavities beneath ice shelves to a small number of drillholes. Studies of sea-ice underwater morphology are limited largely to scientific utilization of submarines. Remotely operated vehicles, tethered to a mother ship by umbilical cable, have been deployed to investigate tidewater-glacier and ice-shelf margins, but their range is often restricted. The development of free-flying autonomous underwater vehicles (AUVs) with ranges of tens to hundreds of kilometres enables extensive missions to take place beneath sea ice and floating ice shelves. Autosub2 is a 3600 kg, 6.7 m long AUV, with a 1600 m operating depth and range of 400 km, based on the earlier Autosub1 which had a 500 m depth limit. A single direct-drive d.c. motor and five-bladed propeller produce speeds of 1–2 m s−1. Rear-mounted rudder and stern-plane control yaw, pitch and depth. The vehicle has three sections. The front and rear sections are free-flooding, built around aluminium extrusion space-frames covered with glass-fibre reinforced plastic panels. The central section has a set of carbon-fibre reinforced plastic pressure vessels. Four tubes contain batteries powering the vehicle. The other three house vehicle-control systems and sensors. The rear section houses subsystems for navigation, control actuation and propulsion and scientific sensors (e.g. digital camera, upward-looking 300 kHz acoustic Doppler current profiler, 200 kHz multibeam receiver). The front section contains forward-looking collision sensor, emergency abort, the homing systems, Argos satellite data and location transmitters and flashing lights for relocation as well as science sensors (e.g. twin conductivity–temperature–depth instruments, multibeam transmitter, sub-bottom profiler, AquaLab water sampler). Payload restrictions mean that a subset of scientific instruments is actually in place on any given dive. The scientific instruments carried on Autosub are described and examples of observational data collected from each sensor in Arctic or Antarctic waters are given (e.g. of roughness at the underside of floating ice shelves and sea ice).
Psychrotrophs, particularly Pseudomonas spp. are known to be the main determinants of the shelf-life of pasteurized milk and refrigerated raw milk. It is presumed that they mainly cause spoilage through the elaboration of proteinase and lipase enzymes. At the time of this research, under the relevant European Directive, one of the means of determining the quality of pasteurized milk was the pre-incubated count, which involves incubating the milk sample for 5 d at 6°C followed by a plate count. Examination of numerous pre-incubated counts revealed a bimodal rather than a normal distribution indicating that the types of contaminants in pasteurized milk may be as important as their initial concentration. Pseudomonads that gave particularly high (>5×106 cfu/ml) and low (<103 cfu/ml) pre-incubated counts were isolated (high and low count isolates respectively). After the organisms had been subjected to a cold shock no consistent trend between the groups of isolates was detected with respect to lag phase duration. However, the high count isolates consistently had a faster exponential growth rate. Unexpectedly, with the exception of one isolate, the low count isolates produced detectable proteinase and lipase earlier. In addition, with one exception, maximal proteinase and lipase production was observed with the low count isolates. These findings indicate that there is no causal relationship between selective growth advantage and ability to produce proteinase and lipase. It also indicates that the spoilage of pasteurized milk is a complex phenomenon and is worthy of further research.
Thirty-two male pigs were used to investigate the effects of nine levels of dietary lysine ranging from 0·41 to 1·30 g lysine per MJ gross energy (GE) on the performance of pigs weaned at 1 to 2 days of age and growing between 2 and 7 kg live weight. The nine dietary lysine treatments, which contained similar levels of GE and balance of essential amino acids, were offered to the pigs at a common feeding level of 2·0 MJ GE per kg metabolic live weight (M075) per day. Growth performance and protein deposition rates increased linearly with increasing dietary lysine content up to about 0·97 g lysine per MJ GE and remained relatively constant thereafter. The response of protein deposition (PD, g/day) in the whole body of pigs to dietary lysine (L, g lysine per MJ GE) was described by three models. The respective regression equation for the quadratic function was PD = -14·23 + 87·66 L – 36·00 L2 and maximum protein deposition occurred at 1·22 g lysine per MJ GE. The rectilinear model, which had an ascending linear phase (PD = 1·49 + 40·10 L, R2 = 0·98, P < 0·001) and a horizontal component representing a mean protein deposition rate of 39·7g/day revealed that maximum protein deposition occurred at 0·95g lysine per MJ GE. Finally, application of the asymptotic model also revealed a highly significant equation: PD = 43·40 — 79·99 × 0·07111, R2 = 0·94, P < 0·001; which indicates a dietary requirement of 1·07 g lysine per MJ GE assuming that the dietary requirement was estimated at 0·90 of the asymptote maximal value. The results indicate that the dietary lysine requirement for pigs during the first 3 weeks of life appears to have changed little over the past 20 years despite substantial changes in genotype.
This study sought to investigate the normal muscle fibre size and type
distribution of the human erector
spinae, both in thoracic and lumbar regions, in a group of 31 young healthy male
(n=17) and female (n=14) volunteers. Two percutaneous muscle biopsy samples
were obtained under local anaesthesia, from the
belly of the left erector spinae, at the levels of the 10th thoracic and 3rd
lumbar vertebrae. Samples were
prepared for routine histochemistry for the identification of fibre types.
Fibre size (cross-sectional area
(CSA) and narrow diameter (ND)) was quantified using computerised image analysis.
The mean CSA/ND
for each fibre type was greater in the thoracic than the lumbar region, but
there was no difference between
the 2 regions either for percentage type I (i.e. percentage distribution by
number), percentage type I area (i.e.
relative area of the muscle occupied by type I fibres) or the ratio describing
the size of the type I fibre
relative to that of the type II. Men had larger fibres than women, for each
fibre type and at both sampling
sites. In the men, each fibre type was of a similar mean size, whereas in the
women the type I fibres were
considerably larger than both the type II A and type II B fibres, with no
difference between the latter two. In
both regions of the erector spinae there was no difference between men and
women for the proportion (%)
of a given fibre type, but the percentage type I fibre area was significantly
higher in the women.
The erector spinae display muscle fibre characteristics which are clearly very
different from those of other
skeletal muscles, and which, with their predominance of relatively large type
I (slow twitch) fibres, befit their
function as postural muscles. Differences between thoracic and lumbar fascicles
of the muscle, and between
the muscles of men and women, may reflect adaptive responses to differences
in function. In assessing the
degree of any pathological change in the muscle of patients with low back
pain, it seems clear that (1) sex
cannot be disregarded and (2) ‘atrophied’ (using the criteria
from other muscles) type II fibres are not
necessarily abnormal for the erector spinae, particularly in women.
Nine organisms were isolated from separate pasteurized milk samples after they had been incubated at 6 °C for 5 d (European Union preincubated count, PIC), four from high count samples (> 5 x 106 cfu/ml) and five from low count samples (< 103 cfu/ml). When the organisms were harvested without overt stress being applied and subjected to a simulated PIC using UHT whole milk, all except one isolate gave comparatively high (> 106 cfu/ml) counts. The imposition of a heat stress at 50 °C prior to a simulated PIC resulted in a segregation of the isolates into those giving high and those giving low counts, which reflected the PIC values of the milk samples from which they were originally isolated. When the isolates were subjected to a cold stress (25 to 4 °C) and inoculated into nutrient broth at 4 °C, the high count isolates were found to have significantly (P < 0·05) shorter lag phases than the low count isolates.
Les problèmes de la dosimétrie dans les champs de rayonnements ionisants diffusés autour des accélérateurs de haute énergie sont présentés. Après une courte introduction sur l'historique des grandeurs physiques utilisées pour
l'acquisition de l'équivalent de dose, les techniques diverses pour la dosimétrie dans des champs mixtes à haute énergie sont décrites, en commençant par des mesures spectrales compliquées, puis par la présentation des moyens en multidétecteurs et en instruments sur la base des détecteurs proportionnels. Enfin l'utilisation de méthodes simples est mise en évidence pour le cas où l'on dispose d'une connaissance initiale et supplémentaire sur la composition des rayonnements ionisants. Il est montré que les résultats des mesures correspondent bien à ceux obtenus à l'aide des programmes de calcul modernes.