66 research outputs found
Enhancing pasture stability and profitability for producers in Poplar Box and Silver-leaved Ironbark woodlands.
Over 7 years, this project collected data about the pasture, tree and soil surface dynamics of two major Aristida/Bothriochloa pasture types within the eucalypt woodlands of central Queensland. Six different grazing management scenarios were compared ecologically and economically, along with the effects of spring burns and tree killing.
Heavy stocking (3-4 ha per adult equivalent) produced the greatest short-term financial return from healthy pastures but was not a sustainable practice and long-term cash returns were no better than those from moderate stocking. The environmental benefits of moderate grazing over heavy grazing were very clear. Light stocking produced better environmental outcomes compared to moderate stocking but was clearly inferior with respect to economic returns. Killing silver-leaved ironbark trees near Rubyvale produced no measurable improvement in pasture growth or quality for at least 6 years whereas at Injune the same treatment of poplar box trees resulted in an immediate and large enhancement in pasture production and carrying capacity. The gritty red duplex soil at Rubyvale was much more erodible than the grey solodic at Injune although the latter becomes very erodible if the stable surface soil is breached.
Good seasonal rainfall produced faster changes in pasture composition than extremes of grazing management. The perennial grasses were easier to recruit than to eliminate by grazing management changes
Update on biomarkers in neuromyelitis optica
Neuromyelitis optica (NMO) (and NMO spectrum disorder) is an autoimmune inflammatory disease of the CNS primarily affecting spinal cord and optic nerves. Reliable and sensitive biomarkers for onset, relapse, and progression in NMO are urgently needed because of the heterogeneous clinical presentation, severity of neurologic disability following relapses, and variability of therapeutic response. Detecting aquaporin-4 (AQP4) antibodies (AQP4-IgG or NMO-IgG) in serum supports the diagnosis of seropositive NMO. However, whether AQP4-IgG levels correlate with disease activity, severity, response to therapy, or long-term outcomes is unclear. Moreover, biomarkers for patients with seronegative NMO have yet to be defined and validated. Collaborative international studies hold great promise for establishing and validating biomarkers that are useful in therapeutic trials and clinical management. In this review, we discuss known and potential biomarkers for NMO
Hodograph method to estimate the latitudinal profile of the field-line resonance frequency using the data from two ground magnetometers
Monitoring the plasmapause using geomagnetic field line resonances
This paper discusses the use of ground magnetometer data to derive plasma mass density profiles of the dayside plasmapause region with spatial and temporal resolution in the range 0.15-0.4 R-E and 20-60 min. This is achieved using cross-phase techniques to identify field line resonance signatures that are not apparent in power spectra. Under quiet conditions, mass density profiles do not show a distinct plasmapause and closely resemble electron density profiles for similar conditions. Under more active conditions the plasmapause can be clearly identified, and its width can be resolved in about 20% of the cases. Spatial integration effects smooth the mass density profiles near the plasmapause boundaries, while comparison of the mass and electron densities allows estimates of the heavy ion mass loading. Temporal variations in the plasmapause position and plasmaspheric density depletions are readily resolved. Sudden changes in solar wind conditions cause a redistribution of plasma within similar to20 min, probably in response to penetration of the magnetospheric electric field into the plasmasphere. Field line resonances occur daily and provide a useful tool for investigating the plasmapause region, especially in conjunction with VLF whistler and in situ particle and imaging experiments. Furthermore, the extensive existing suites of magnetometer data permit retrospective studies of focus intervals
Calculating sediment trapping efficiency for reservoirs in series
Trapping Efficiency (TE) is defined as the proportion of inflowing sediment that is accumulated in a reservoir. Accurately predicting the trapping efficiency (TE) of sediment in reservoirs is critical to estimate their useful life and inform catchment models for sediment budget estimation. A daily formulation of the Churchill sediment trapping efficiency equation previously implemented in the eWater Source modelling framework, enables the user to account for the accumulation of sediment and hence the subsequent sediment yield exiting a reservoir. Where reservoirs are in series, the particle size of sediment passing through an upstream storage is generally finer than the 'local' sediment. Therefore, the application of the Churchill equation to each reservoir in isolation, not taking into account the different sources of sediment, may result in an under prediction of the sediment yield for a basin. Churchill (1948) proposed a method to account for sediment that had already passed through an upstream reservoir
A method for the measurement of the cross-sections for the production of radioisotopes by charged particles from a cyclotron
Impact of Expressive Wrinkles on Perception of a Virtual Character’s Facial Expressions of Emotions
Facial animation has reached a high level of photorealism. Skin is rendered with grain and translucency, wrinkles are accurate and dynamic. These recent visual improvements are not fully tested for their contribution to the perceived expressiveness of virtual characters. This paper presents a perceptual study assessing the impact of different rendering modes of expressive wrinkles on users’ perception of facial expressions of basic and complex emotions. Our results suggest that realistic wrinkles increase agent’s expressivity and user’s preference, but not the recognition of emotion categories. This study was conducted using our real time facial animation platform that is designed for perceptive evaluations of affective interaction
Monitoring spatial and temporal variations in the dayside plasmasphere using geomagnetic field line resonances
It is well known that the resonant frequency of geomagnetic field lines is determined by the magnetic field and plasma density. We used cross-phase and related methods to determine the field line resonance frequency across 2.4≤<L≤4.5 in the Northern Hemisphere at 78°–106° magnetic longitude and centered on L=2.8 in the Southern Hemisphere at 226° magnetic longitude, for several days in October and November 1990. The temporal and spatial variation in plasma mass density was thus determined and compared with VLF whistler measurements of electron densities at similar times and locations. The plasma mass loading was estimated and found to be low, corresponding to 5–10% He+ on the days examined. The plasma mass density is described by a law of the form (R/Req)−p, where p is in the range 3–6 but shows considerable temporal variation, for example, in response to changes in magnetic activity. Other features that were observed include diurnal trends such as the sunrise enhancement in plasma density at low latitudes, latitude-dependent substorm refilling effects, shelves in the plasma density versus L profile, and a longitudinal asymmetry in plasma density. We can also monitor motion of the plasmapause across the station array. Properties of the resonance were examined, including the resonance size, Q, and damping. Finally, we note the appearance of fine structure in power spectra at these latitudes, suggesting that magnetospheric waveguide or cavity modes may be important in selecting wave frequencies
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