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1.
The St. Clair-Detroit River System contains a world-class Great Lakes muskellunge (Esox masquinongy) fishery that has avoided the declines observed in many Great Lakes muskellunge populations. Muskellunge are an upper trophic level predator, and therefore a naturally low-density species. Limited fishery-independent data exist on which to base management decisions. To remedy this, we initiated an acoustic telemetry study in May of 2016, in collaboration with the Great Lakes Acoustic Telemetry Observation System. Our objective was to describe patterns of movement of muskellunge in this large and open system to better understand their spatial ecology. We acoustically tagged 133 muskellunge in the Detroit River and Lake St. Clair, and movements of 58 fish that passed our data quality control screens were analyzed. We utilized mixed modelling to assess the effects of sex, length, release location, and season on daily movement rates. We found that movement rates only differed among seasons, with highest movement rates occurring in the fall and lowest movement rates in the winter. Muskellunge tagged at different locations exhibited distinct residency patterns, and fish frequently crossed jurisdictional and waterbody boundaries. Ultimately our study highlights the scope and patterns of muskellunge movement in a large, unimpounded system and demonstrates that management of these fish would benefit from consideration of their full distribution covering multiple management jurisdictions.  相似文献   
2.
The thermal expansion and magnetic behaviors of divalent, alkaline‐doped lanthanum ferrites (La0.9M0.1FeO3, M=Ca, Sr, Ba) were assessed using a combination of dilatometry, magnetometry, time‐of‐flight neutron diffraction, and high‐temperature X‐ray diffraction. Néel temperatures were determined through vibrating sample magnetometry and correlated well with changes in thermal expansion behavior observed during both dilatometry and X‐ray diffraction. The Néel temperatures observed for pure, Ca‐doped, Sr‐doped, and Ba‐doped lanthanum ferrites were 471°C, 351°C, 465°C, and 466°C, respectively. The effect of divalent substitutions on the magnetic behavior are attributed to charge compensation mechanisms and structural changes in the material.  相似文献   
3.
Transient thermography is commonly used for the detection of disbonds in thermal barrier coatings (TBC). As for other NDT techniques, reference test specimens are required for calibration, but unfortunately, real disbonds are very difficult to use because it is difficult to control their size, and large ones tend to spall. Flat bottomed holes are commonly used, but these over-estimate the thermal contrast obtained for a defect of a given diameter. This paper quantifies the differences in thermal response using finite element analysis validated by experiments, and proposes a form of artificial disbond that gives a better representation of the thermal responses seen with real defects. Real disbonds tend to have a non-uniform gap between the disbonded surfaces across the defect, and the effect of this on the thermal response is evaluated using finite element simulations. It is shown that the effect can be compensated for by adjusting the diameter of the calibration defect compared to the real defect.  相似文献   
4.
Cerium sulfides were prepared by high‐energy milling of cerium and sulfur. The reaction kinetics were observed by monitoring temperature and pressure in situ. For the first time, it is demonstrated that cerium monosulfide, which has historically been produced only at very high temperatures using both toxic and flammable gases, can be produced from a stoichiometric mixture of the elemental powders at near room temperature. It is shown that the monosulfide is produced through a mechanochemically induced self‐propagating reaction of intermediate compounds.  相似文献   
5.
In this article, I derive sufficient conditions for an orthogonal main-effect plan having k factors at S i levels, i = 1, …, k, to have a minimal number of observations. These sufficient conditions are then used to show that many of the orthogonal main-effect plans given prcviously in the literature have minimal numbers of observations.  相似文献   
6.
Workplace violence is a leading form of occupational injury and fatality, but has received little attention from the ergonomics research community. The paper reports findings from the 2012 New Zealand Workplace Violence Survey, and examines the workplace violence experience of 86 New Zealand organisations and the perceptions of occupational health and safety professionals from a systems perspective. Over 50% of respondents reported violence cases in their organisation, with perpetrators evenly split between co-workers and external sources such as patients. Highest reported levels of violence were observed for agriculture, forestry and construction sectors. Highest risk factor ratings were reported for interpersonal and organisational factors, notably interpersonal communication, time pressure and workloads, with lowest ratings for environmental factors. A range of violence prevention measures were reported, although most organisations relied on single control measures, suggesting unmanaged violence risks were common among the sample.  相似文献   
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8.
When task-switching studies use the task-cuing procedure with a 1:1 cue–task mapping, task switching and cue switching are confounded, which is problematic for interpreting switch costs. The use of a 2:1 cue–task mapping is a potential solution to this problem, but it is possible that introducing more cues may also introduce marked changes in task-switching performance. In 5 experiments involving 160 subjects, the authors compared performance with 1:1 and 2:1 mappings across several methodological changes. Differences in switch costs between mappings were small and, in most analyses, nonsignificant. In all experiments, both mappings yielded significant reductions in switch cost across cue–target interval, and there were significant cue-switching effects with the 2:1 mapping. A model of cue encoding fit the data from both mappings about equally well. Overall, task-switching performance was more similar than it was different between mappings, leading the authors to suggest that the use of a 2:1 mapping is a viable solution to the problem associated with a 1:1 mapping. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
Augmentation of potable water sources by planned indirect potable reuse of wastewater is being widely considered to address growing water shortages. Environmental buffers such as lakes and dams may act as one of a series of barriers to potable water contamination stemming from micropollutants in wastewater. In South-East Queensland, Australia, current government policy is to begin indirect potable reuse of water from reverse osmosis equipped advanced water treatment plants (AWTPs) when the combined capacity of its major storages is at 40% capacity. A total of 15 organic contaminants including NDMA and bisphenol A have been publically reported as detected in recycled water from one of South-East Queensland’s AWTPs, while another 98 chemicals were analysed for, but found to be below their detection limit. To assess the natural attenuation in Lake Wivenhoe, a Level III fugacity based evaluative fate model was constructed using the maximum concentrations of these contaminants detected as input data. A parallel aquivalence based model was constructed for those contaminants, such as dichloroacetic acid, dalapon and triclopyr, which are ionised in the environment of Lake Wivenhoe. A total of 247 organic chemicals of interest, including disinfection by-products, pesticides, pharmaceuticals and personal care products, xenoestrogens and industrial chemicals, were evaluated with the model to assess their potential for natural attenuation. Out of the 15 detected chemicals, trihalomethanes are expected to volatilise with concentrations in the outflow from the dam approximately 400 times lower than influent from the AWTPs. Transformation processes in water are likely to be more significant for NDMA and pharmaceuticals such as salicylic acid and paracetamol as well as for caffeine and the herbicides dalapon and triclopyr. For hydrophobic contaminants such as cholesterol and phenolic xenoestrogens such as 4-nonylphenol, 4-t-octylphenol and bisphenol A, equilibrium between water and sediments will not be attained and hence fate processes such as removal in outflow are predicted to become relatively important.  相似文献   
10.
The researchers surveyed 295 members of the Association for Play Therapy on their attitudes related to working with families when treating children. The results indicated the majority of play therapists held attitudes conducive to involving families in their approaches with children. However, mixed findings were found in specific areas related to the implementation of play therapy with families, suggesting barriers may exist. These mixed findings included a decreased percentage of play therapists that felt like play therapy was effective in family therapy when compared with the high level who felt that play and family therapy approaches could be integrated. Moreover, the respondents were divided on issues such as parents' willingness to be involved in therapy with their children and if parents were actually resistant to being included in sessions with their children. These mixed findings suggest that a wide range of attitudes and experiences about parental involvement exist among play therapists in the field. The authors raise key questions for the play therapy field to consider in more depth and suggest improvements that may be needed in play therapy education to increase the efficacy of play therapists' skills in working with families. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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