247 research outputs found
Evaluation of Florpyrauxifenbenzyl for the control of Cyperus aromaticus (Navua sedge).
Background:
Cyperus aromaticus (Navua sedge) is a creeping perennial sedge common to tropical environments, currently threatening many agroecosystems and ecosystems in Pacific Island countries and northern Queensland in Australia.
Objective:
A glasshouse study was conducted to evaluate the efficacy of florpyrauxifen-benzyl on C. aromaticus plants with and without established rhizomes.
Methods:
The plants with established rhizomes were treated at three application times being mowed, pre-flowering and flowering growth stages and plants without established rhizomes were treated at seedling, pre-flowering and flowering growth stages. At each application time, plants were treated with four rates of florpyrauxifen-benzyl: 0, 15, 30 and 60 g a.i. ha−1 and control.
Results:
There was no mortality in the plants with established rhizomes. Reduction in the number of tillers was observed at four weeks after treatment (WAT) in plants treated with 30 and 60 g a.i. ha−1 of herbicide, however, there was new growth from the rhizomes and the number of tillers increased at 8 WAT. Conversely, florpyrauxifen-benzyl provided above 95% control in plants without established rhizomes.
Conclusions:
These results indicate florpyrauxifen-benzyl can help manage a new C. aromaticus infestation prior to the establishment of rhizomes. However, it has little to no impact on C. aromaticus plants with established rhizomes, and other management options should be employed to control them
Local topography increasingly influences the mass balance of a retreating cirque glacier
Local topographically driven processes – such as wind drifting, avalanching,
and shading – are known to alter the relationship between the mass balance
of small cirque glaciers and regional climate. Yet partitioning such local
effects from regional climate influence has proven difficult, creating
uncertainty in the climate representativeness of some glaciers. We address
this problem for Sperry Glacier in Glacier National Park, USA, using
field-measured surface mass balance, geodetic constraints on mass balance,
and regional climate data recorded at a network of meteorological and snow
stations. Geodetically derived mass changes during 1950–1960, 1960–2005,
and 2005–2014 document average mass change rates during each period at
−0.22 ± 0.12, −0.18 ± 0.05, and
−0.10 ± 0.03 m w.e. yr−1, respectively. A correlation of field-measured mass balance and regional
climate variables closely (i.e., within 0.08 m w.e. yr−1) predicts
the geodetically measured mass loss from 2005 to 2014. However, this
correlation overestimates glacier mass balance for 1950–1960 by
+1.20 ± 0.95 m w.e. yr−1. Our analysis suggests that local
effects, not represented in regional climate variables, have become a more
dominant driver of the net mass balance as the glacier lost 0.50 km2
and retreated further into its cirque
An investigation of the effects of stage of ensilage on Nassella neesiana seeds, for reducing seed viability and injury to livestock
The noxious weed Nassella neesiana is established on a wide range of productive land throughout southeastern Australia. N. neesiana seeds, when mature, are sharp, causing injury to livestock, thus posing a problem in fodder bales. To reduce infestations of agricultural weeds in situ, production of silage from weed-infested pastures is practised as part of integrated weed management (IWM). However, there is little data to demonstrate whether this process is useful to reduce infestations or the harmful properties of N. neesiana. Therefore, the minimum duration of ensilage required to reduce the viability of N. neesiana seeds was investigated, both with and without addition of ensilage inoculants in this process. Also, the decreasing propensity of the seeds to injure livestock, after various times and conditions of ensilage, was assessed. Ensilage inoculant reduced seed germination probability to zero after 35 days. When no inoculant was added, zero viability was achieved after 42 days. A qualitative assessment of the hardness of ensilaged seeds found seed husks were softer (and therefore safer) after 42 days, whether inoculant was used or not. Therefore, we suggest that both the viability of N. neesiana seeds and hardness of seed casings are significantly reduced after 42 days, thereby reducing the risks of seed dispersal and injury to livestock
MLP: a MATLAB toolbox for rapid and reliable auditory threshold estimation
In this paper, we present MLP, a MATLAB toolbox enabling auditory
thresholds estimation via the adaptive Maximum Likelihood procedure proposed
by David Green (1990, 1993). This adaptive procedure is particularly appealing for
those psychologists that need to estimate thresholds with a good degree of accuracy
and in a short time. Together with a description of the toolbox, the current text
provides an introduction to the threshold estimation theory and a theoretical
explanation of the maximum likelihood adaptive procedure. MLP comes with a
graphical interface and it is provided with several built-in, classic psychoacoustics
experiments ready to use at a mouse click
Effects of stimulus duration on audio-visual synchrony perception
The integration of visual and auditory inputs in the human brain occurs only if the components are perceived in temporal proximity, that is, when the intermodal time difference falls within the so-called subjective synchrony range. We used the midpoint of this range to estimate the point of subjective simultaneity (PSS). We measured the PSS for audio-visual (AV) stimuli in a synchrony judgment task, in which subjects had to judge a given AV stimulus using three response categories (audio first, synchronous, video first). The relevant stimulus manipulation was the duration of the auditory and visual components. Results for unimodal auditory and visual stimuli have shown that the perceived onset shifts to relatively later positions with increasing stimulus duration. These unimodal shifts should be reflected in changing PSS values, when AV stimuli with different durations of the auditory and visual components are used. The results for 17 subjects showed indeed a significant shift of the PSS for different duration combinations of the stimulus components. Because the shifts were approximately equal for duration changes in either of the components, no net shift of the PSS was observed as long as the durations of the two components were equal. This result indicates the need to appropriately account for unimodal timing effects when quantifying intermodal synchrony perceptio
Modeling the Individual Variability of Loudness Perception with a Multi-Category Psychometric Function
The Immunosuppressant FTY720 (Fingolimod) enhances Glycosaminoglycan depletion in articular cartilage
Auditory-inspired morphological processing of speech spectrograms: applications in automatic speech recognition and speech enhancement
New auditory-inspired speech processing methods are presented in this paper, combining spectral subtraction and two-dimensional non-linear filtering techniques originally conceived for image processing purposes. In particular, mathematical morphology operations, like erosion and dilation, are applied to noisy speech spectrograms using specifically designed structuring elements inspired in the masking properties of the human auditory system. This is effectively complemented with a pre-processing stage including the conventional spectral subtraction procedure and auditory filterbanks. These methods were tested in both speech enhancement and automatic speech recognition tasks. For the first, time-frequency anisotropic structuring elements over grey-scale spectrograms were found to provide a better perceptual quality than isotropic ones, revealing themselves as more appropriate—under a number of perceptual quality estimation measures and several signal-to-noise ratios on the Aurora database—for retaining the structure of speech while removing background noise. For the second, the combination of Spectral Subtraction and auditory-inspired Morphological Filtering was found to improve recognition rates in a noise-contaminated version of the Isolet database.This work has been partially supported by the Spanish Ministry of Science and Innovation CICYT Project No. TEC2008-06382/TEC.Publicad
Dealing with Alcohol-related problems in the Night-Time Economy: A Study Protocol for Mapping trends in harm and stakeholder views surrounding local community level interventions
<p>Abstract</p> <p>Background</p> <p>This project will provide a comprehensive investigation into the prevalence of alcohol-related harms and community attitudes in the context of community-based interventions being implemented to reduce harm in two regional centres of Australia. While considerable experimentation and innovation to address these harms has occurred in both Geelong and Newcastle, only limited ad-hoc documentation and analysis has been conducted on changes in the prevalence of harm as a consequence, leaving a considerable gap in terms of a systematic, evidence-based analysis of changes in harm over time and the need for further intervention. Similarly, little evidence has been reported regarding the views of key stakeholder groups, industry, government agencies, patrons or community regarding the need for, and the acceptability of, interventions to reduce harms. This project will aim to provide evidence regarding the impact and acceptability of local initiatives aimed at reducing alcohol-related harms.</p> <p>Methods/Design</p> <p>This study will gather existing police data (assault, property damage and drink driving offences), Emergency Department presentations and Ambulance attendance data. Further, the research team will conduct interviews with licensed venue patrons and collect observational data of licensed venues. Key informant interviews will assess expert knowledge from key industry and government stakeholders, and a community survey will assess community experiences and attitudes towards alcohol-related harm and harm-reduction strategies. Overall, the project will assess: the extent of alcohol-related harm in the context of harm-reduction interventions, and the need for and acceptability of further intervention.</p> <p>Discussion</p> <p>These findings will be used to improve evidence-based practice both nationally and internationally.</p> <p>Ethical Approval</p> <p>This project has been approved by Deakin University HREC.</p
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