984 resultados para Locations


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Although soils are generally considered to wet readily, some are actually water repellent at the surface and in the rhizosphere. This phenomenon occurs at low to moderate moisture contents and has been reported from soils under a range of vegetation types and from many regions around the globe. Water repellency in soils can have serious environmental implications including reduced seed germination and plant growth as well as irrigation efficiency, accelerated soil erosion, and enhanced leaching of agrochemicals through preferential flow. it has been proposed that water repellency is caused by the accumulation of hydrophobic organic compounds released as root exudates, microbial byproducts or from decomposing organic matter, which are deposited on mineral or aggregate surfaces, or are present as interstitial matter, Few studies to date have attempted to isolate and characterize these compounds and their structure is therefore only poorly understood, These studies have generally focussed on only a single soil or a small range of samples, have not included non-repellent soils as a control and have not always been able to demonstrate that the substances isolated are indeed responsible for repellency formation.

This study reports on the first part (extraction procedures) of a research programme addressing these gaps in current knowledge by investigating a wide range of severely repellent and wettable ‘control’ samples from different countries, and by including assessments of extraction efficiency and ability of extracts to cause repellency. Analytical methods include DRIFT (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) of soils and IR (Infrared) analysis of extracts.

Key findings are that (i) soil sample heating after extraction is valuable in assessing the effectiveness of the extraction procedure, (ii) Soxhlet extraction using isopropanol/ ammonia (70/30 v/v) was the most effective method in extracting hydrophobic compounds, while leaving the ability of extracted compounds to induce water repellency virtually unaffected, (iii) wettable control soils also contain hydrophobic substances capable of inducing water repellency, (iv) the amount of organic compounds extracted was poorly related to sample repellency, indicating that compounds responsible for repellency may only represent a small fraction of the extract, (v) differences in extraction efficiency between different samples indicate that the compounds responsible may differ generically and/or in terms of their bonding to minerals, and (vi) the combination of repellency assessments with DRIFT on soils and JR on extracts used with internal standards has considerable potential to allow quantification of CH bearing organic matter in the soil, the efficiency of extraction processes for its removal, and its significance in causing water repellency in soils.

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The dive behaviour, foraging locations, and colony-attendance patterns of female Australian fur seals (Arctocephalus pusillus doriferus) from Kanowna Island (39°10'S, 146°18'E) in Bass Strait, southeastern Australia, were determined throughout lactation during 1997–1999. Foraging-trip durations increased as lactation progressed, being shortest in summer (3.71 ± 0.24 days; mean ± 1 SE) and longest in winter (6.77 ± 0.57 days, P < 0.05), but maternal-attendance periods did not differ in duration (1.70 ± 0.10 days, P > 0.5). Individual mean attendance periods and trip durations were positively correlated (r2 = 0.21, P < 0.005). Diving commenced shortly after seals left the colony (2.6 ± 0.4 h), was continuous for long periods (up to 36 h), occurred mostly during daylight hours, and lacked regular diel variation in depth. The majority of dives (78%) were typically U-shaped and reached depths corresponding to the prevailing depths in Bass Strait (65–85 m), indicating that these animals forage mostly on the benthos of the shallow continental shelf in this region. Such behaviour is unusual for fur seals but is reminiscent of that of some sea lion species. Mean dive durations varied between 2.0 and 3.7 min (maximum 8.9 min) and the theoretical aerobic dive limit (3.91–4.26 min) was exceeded on 17.3% of dives. Dive frequency (8.3 ± 0.6/h) and the proportion of time at sea spent diving (40.7 ± 2.1%) were weakly negatively related to the duration of the foraging trip (r2= 0.07, P < 0.004, and r2 = 0.13, P < 0.0001, respectively). Data from at-sea locations showed that lactating females forage almost exclusively within Bass Strait during all seasons.

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The aim of this study was to develop and test the reliability and validity of survey items that examine the frequency with which primary school-aged children play in particular outdoor locations. Parents reported the number of days their child spent playing in specified outdoor locations (i.e., yard at home, own street/court/footpath, and park/playground) out-of-school hours on weekdays and weekend days during a typical week. To test the reliability of these items, the survey was administered on two occasions, 2 weeks apart, to a sample of 53 parents of children attending primary schools located in metropolitan Melbourne. The validity study involved the completion of a log book by 46 parents of primary school children over a 1-week period. Two weeks later, the same sample of parents completed the survey items. The test–retest reliability of individual items was determined using intra-class correlation coefficients (ICC). The kappa statistic and percent agreement between responses were used to assess validity by comparing the information provided in the log book with that provided in the survey. Results from the two studies suggest that the survey was generally a reliable and valid instrument for assessing the frequency with which children play in particular locations especially at home or in the street. Evidence of the reliability and validity of items assessing where children play is novel and important considering the need to promote children's physical activity in a variety of settings.

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This paper sought to explore the push [internal] motivations of eco-tourists and the influence of these motivational drives on their future ecotourism intentions. Findings from this exploratory study identified five key internal motivations, namely, 'self-esteem', 'relaxation', 'social interaction', 'self-fulfilment' and 'thrill and excitement'. Further analysis identified that 'self-esteem', elaxation' and 'self-fulfilment' motives were significantly related to ecotourist's intention to volunteer as well as their intention to donate money to an eco-tourism destination. Additionally, 'self-fulfilment' and 'thrill and excitement' motives were identified as impacting upon eco-tourists’ future attendance intentions. Consequently, findings from this research provide eco-tourism operators with insight into eco-tourist motivations to inform product and brand development and promotional activities and assist in the ongoing development effective eco-tourist retention strategies.

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This review examines the current state of knowledge related to the location of fast food restaurants. Previous studies have revealed some communities are more exposed to fast food restaurants. However, the influence of increased exposure to fast food on dietary behaviours remains unresolved. This is identified as an area of priority for future research.

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Background: ARGOS satellite telemetry is one of the most widely used methods to track the movements of free-ranging marine and terrestrial animals and is fundamental to studies of foraging ecology, migratory behavior and habitat-use. ARGOS location estimates do not include complete error estimations, and for many marine organisms, the most commonly acquired locations (Location Class 0, A, B, or Z) are provided with no declared error estimate.
Methodology/Principal Findings: We compared the accuracy of ARGOS locations to those obtained using Fastloc GPS from the same electronic tags on five species of pinnipeds: 9 California sea lions (Zalophus californianus), 4 Galapagos sea lions (Zalophus wollebaeki), 6 Cape fur seals (Arctocephalus pusillus pusillus), 3 Australian fur seals (A. p. doriferus) and 5 northern elephant seals (Mirounga angustirostris). These species encompass a range of marine habitats (highly pelagic vs coastal), diving behaviors (mean dive durations 2–21 min) and range of latitudes (equator to temperate). A total of 7,318 ARGOS positions and 27,046 GPS positions were collected. Of these, 1,105 ARGOS positions were obtained within five minutes of a GPS position and were used for comparison. The 68th percentile ARGOS location errors as measured in this study were LC-3
0.49 km, LC-2 1.01 km, LC-1 1.20 km, LC-0 4.18 km, LC-A 6.19 km, LC-B 10.28 km.
Conclusions/Significance: The ARGOS errors measured here are greater than those provided by ARGOS, but within the range of other studies. The error was non-normally distributed with each LC highly right-skewed. Locations of species that make short duration dives and spend extended periods on the surface (sea lions and fur seals) had less error than species like elephant seals that spend more time underwater and have shorter surface intervals. Supplemental data (S1) are provided allowing the creation of density distributions that can be used in a variety of filtering algorithms to improve the quality of ARGOS tracking data.

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Purpose – Property performance indices have invariably focused upon prime markets with a variety of approaches used to measure investment returns. However, there is relatively little knowledge regarding the investment performance of property in regeneration areas. Indeed, there is a perception that such locations carry increased risk and that the returns achieved may not be sufficient to offset the added risk. The main objective of this paper, therefore, is to construct regeneration property performance indicators consistent with the CBRE rent index and average yield monitor.

Design/methodology/approach – Local market experts were asked to estimate rents and yields for hypothetical standardised offerings for a range of regeneration locations throughout the UK, covering the period 1995 to 2002.

Findings – The results show that rental growth was similar in regeneration locations compared to the prime market. However, the analysis highlights a major yield shift for property in regeneration areas in the short to medium term. The downward pressure in yields would suggest that once a regeneration area becomes established and rental growth emerges, investor interest is stimulated resulting in increased competition and a shortening of yields.

Originality/value – The significance of this research is the quantification of property investment performance from regeneration areas that previously has not been available to investment institutions and decision makers. From a policy perspective this analysis is of relevance in confirming the maturing of locations that have received high levels of public sector support and indicating the effectiveness of regeneration policy mechanisms in creating sustainable urban environments capable of meeting private sector investment goals.

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The “element of romanticization” or the constant yearning for ones roots—sensory and spatial locations—has become a phenomenon for different immigrant groups. As it is the politics of sensory and spatial locations that act as one of the core features that join Indian Diaspora across continents. The short stories analysed in this paper attempt to provide an understanding of the variety of interpretations of the sensory and spatial locations. We can note that in most of these stories the immigrants try to bring the Indian subcontinent to Australia with them by using myths, legends, historical facts, etc. These immigrants besides using myths also display a proudest possession, which reminds them constantly of home. These objects or icons or elements from the past, which the immigrants carry with them as cultural products are used as helpers in making a sense out of the alien situation presented before them. The paper concludes with the assertion that Indian-Australian short stories act as an important expression of the Indian way of life in Australia and may also effectively help in removing misconceptions and better understandings of local conditions thus encouraging fellow Australians to see differently within the cultural context of India and Australia.

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Finding the skeleton of a 3D mesh is an essential task for many applications such as mesh animation, tracking, and 3D registeration. In recent years, new technologies in computer vision such as Microsoft Kinect have proven that a mesh skeleton can be useful such as in the case of human machine interactions. To calculate the 3D mesh skeleton, the mesh properties such as topology and its components relations are utilized. In this paper, we propose the usage of a novel algorithm that can efficiently calculate a vertex antipodal point. A vertex antipodal point is the diametrically opposite point that belongs to the same mesh. The set of centers of the connecting lines between each vertex and its antipodal point represents the 3D mesh desired skeleton. Post processing is completed for smoothing and fitting centers into optimized skeleton parts. The algorithm is tested on different classes of 3D objects and produced efficient results that are comparable with the literature. The algorithm has the advantages of producing high quality skeletons as it preserves details. This is suitable for applications where the mesh skeleton mapping is required to be kept as much as possible.