171 research outputs found
The European cycle route network Eurovelo: challenges and opportunities for sustainable tourism
The European Cycle Route Network EuroVelo: challenges and opportunities for sustainable tourism. Update of the 2009 study
Understanding cycle tourism experiences at the Tour Down Under
Sport tourism experiences are subjective and emotional, laden with symbolic meaning. This study explores the experiences of participants who adopted the multiple roles of both an active participant and event spectator, within the parameters of one chosen sporting event. A professional cycling race event, the Tour Down Under in South Australia was chosen for this investigation, and 20 face-to-face individual interviews were conducted with cycle tourists. The three main themes emerging from the data were the interaction of people and temporary spaces on a sport tourism ‘stage’; the co-creation of authentic personal experiences and meanings; and identity reinforcement and the development of a sense of belonging. Consequently, a model for understanding sport event tourism experiences is proposed. The findings suggest that providing tourists with authentic and memorable experiences lies at the heart of what constitutes sport tourism. Whilst the results demonstrate that cycling events provide the individual with a sense of belonging or membership to a wider social group, they also illustrate that there is a continued need for more focused and nuanced approaches towards understanding sport tourism experiences that reflect the ever-increasing diversity and complexity of the interaction between sport, events and tourism
Control of Length and Spatial Functionality of Single-Wall Carbon Nanotube AFM Nanoprobes
Single-wall carbon nanotube (SWNT) nanofibrils were assembled onto conductive
atomic force microscopy (AFM) probes with the help of dielectrophoresis (DEP).
This process involved the application of a 10 V, 2 MHz, AC bias between a
metal-coated AFM probe and a dilute suspension of SWNTs. This exerted a
positive dielectrophoretic force onto the nanotubes that caused them to align
while precipitating out onto the probe. The gradual removal of the AFM probe
away from the SWNT suspension consolidated these nanotubes into nanofibrils
with a high degree of alignment as demonstrated with polarization Raman
experiments. By varying the pulling speed, immersion time, and concentration of
the SWNT suspension, one can tailor the diameter and thus the stiffness of
these probes. Precise length trimming of these nanofibrils was also performed
by their gradual immersion and dissolution into a liquid that strongly
interacted with nanotubes, (i.e., sodium dodecyl sulfate (SDS) solution).
Vacuum annealing these nanoprobes at temperature up to 450 degree C further
increased their stiffness and rendered them insoluble to SDS and all other
aqueous media. Regrowth of a new SWNT nanofibril from the side or at the end of
a previously grown SWNT nanofibril was also demonstrated by a repeated
dielectrophoretic assembly at the desired immersion depth. These SWNT
nanofibril-equipped AFM probes are electrically conductive and mechanically
robust for use as high-aspect-ratio electrochemical nanoprobes
New Colloidal Lithographic Nanopatterns Fabricated by Combining Pre-Heating and Reactive Ion Etching
We report a low-cost and simple method for fabrication of nonspherical colloidal lithographic nanopatterns with a long-range order by preheating and oxygen reactive ion etching of monolayer and double-layer polystyrene spheres. This strategy allows excellent control of size and morphology of the colloidal particles and expands the applications of the colloidal patterns as templates for preparing ordered functional nanostructure arrays. For the first time, various unique nanostructures with long-range order, including network structures with tunable neck length and width, hexagonal-shaped, and rectangular-shaped arrays as well as size tunable nanohole arrays, were fabricated by this route. Promising potentials of such unique periodic nanostructures in various fields, such as photonic crystals, catalysts, templates for deposition, and masks for etching, are naturally expected
Opportunities for mobilizing recalcitrant phosphorus from agricultural soils: a review
Background : Phosphorus (P) fertilizer is usually applied
in excess of plant requirement and accumulates in soils
due to its strong adsorption, rapid precipitation and
immobilisation into unavailable forms including organic
moieties. As soils are complex and diverse chemical,
biochemical and biological systems, strategies to access
recalcitrant soil P are often inefficient, case specific and
inconsistently applicable in different soils. Finding a
near-universal or at least widely applicable solution to
the inefficiency in agricultural P use by plants is an
important unsolved problem that has been under investigation
for more than half a century.
Scope : In this paper we critically review the strategies
proposed for the remobilization of recalcitrant soil phosphorus for crops and pastures worldwide. We have
additionally performed a meta-analysis of available soil
31P–NMR data to establish the potential agronomic
value of different stored P forms in agricultural soils.
Conclusions : Soil inorganic P stocks accounted on average
for 1006 ± 115 kg ha−1 (57 ± 7%), while the
monoester P pool accounted for 587 ± 32 kg ha−1
(33 ± 2%), indicating the huge potential for the future
agronomic use of the soil legacy P. New impact driven
research is needed in order to create solutions for the
sustainable management of soil P stocks
Inter- and intra-species intercropping of barley cultivars and legume species, as affected by soil phosphorus availability
Aims: Intercropping can improve plant yields and
soil phosphorus (P) use efficiency. This study
compares inter- and intra-species intercropping,
and determines whether P uptake and shoot biomass
accumulation in intercrops are affected by
soil P availability.
Methods: Four barley cultivars (Hordeum vulgare L.)
and three legume species (Trifolium subterreneum,
Ornithopus sativus and Medicago truncatula) were selected
on the basis of their contrasting root exudation
and morphological responses to P deficiency. Monocultures
and barley-barley and barley-legume intercrops
were grown for 6 weeks in a pot trial at very limiting,
slightly limiting and excess available soil P. Aboveground
biomass and shoot P were measured.
Results: Barley-legume intercrops had 10–70%
greater P accumulation and 0–40% greater biomass
than monocultures, with the greatest gains occurring
at or below the sub-critical P requirement for
barley. No benefit of barley-barley intercropping
was observed. The plant combination had no significant
effect on biomass and P uptake observed
in intercropped treatments.
Conclusions: Barley-legume intercropping shows
promise for sustainable production systems, especially
at low soil P. Gains in biomass and P uptake
come from inter- rather than intra-species
intercropping, indicating that plant diversity resulted
in decreased competition between plants for P
Laser-wakefield accelerators for high-resolution X-ray imaging of complex microstructures
Laser-wakefield accelerators (LWFAs) are high acceleration-gradient plasma-based particle accelerators capable of producing ultra-relativistic electron beams. Within the strong focusing fields of the wakefield, accelerated electrons undergo betatron oscillations, emitting a bright pulse of X-rays with a micrometer-scale source size that may be used for imaging applications. Non-destructive X-ray phase contrast imaging and tomography of heterogeneous materials can provide insight into their processing, structure, and performance. To demonstrate the imaging capability of X-rays from an LWFA, we have examined an irregular eutectic in the aluminum-silicon (Al-Si) system. The lamellar spacing of the Al-Si eutectic microstructure is on the order of a few micrometers, thus requiring high spatial resolution. We present comparisons between the sharpness and spatial resolution in phase contrast images of this eutectic alloy obtained via X-ray phase contrast imaging at the Swiss Light Source (SLS) synchrotron and X-ray projection microscopy via an LWFA source. An upper bound on the resolving power of 2.7 ± 0.3 µm of the LWFA source in this experiment was measured. These results indicate that betatron X-rays from LWFA can provide an alternative to conventional synchrotron sources for high resolution imaging of eutectics and, more broadly, complex microstructures
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