Putting the wood back into our rivers: an experiment in river rehabilitation

This paper presents an overview of a project established to assess the effectiveness of woody debris (WD) reintroduction as a river rehabilitation tool. An outline of an experiment is presented that aims to develop and assess the effectiveness of engineered log jams (ELJs) under Australian conditions, and to demonstrate the potential for using a range of ELJs to stabilise a previously de-snagged, high energy gravel-bed channel. Furthermore, the experiment will test the effectiveness of a reach based rehabilitation strategy to increase geomorphic variability and hence habitat diversity. While primarily focusing on the geomorphic and engineering aspects of the rehabilitation strategy, fish and freshwater mussel populations are also being monitored. The project is located within an 1100m reach of the Williams River, NSW. Twenty separate ELJ structures were constructed, incorporating a total of 430 logs placed without any artificial anchoring (e.g., no cabling or imported ballast). A geomorphic control reach was established 3.1 km upstream of the project reach. In the 6 months since the structures were built the study site has experienced 6 flows that have overtopped most structures, 3 of the flows were in excess of the mean annual flood, inundating 19 of the ELJs by 2 - 3 m, and one by 0.5 m. Early results indicate that with the exception of LS4 and LS5, all structures are performing as intended and that the geomorphic variability of the reach has substantially increased

Designing public agencies for 21st century water–energy–food nexus complexity : the case of Natural Resources Wales

Public environmental organisations face a Herculean task: to be responsive to public and executive expectations for decentralisation, integration, increasing accountabilities and efficiency savings plus, contemporaneously, managing increasingly complex nature–society systems as exemplified by the water–energy–food nexus. The public-agency innovation literatures and contingency theory offer partial explanations for this challenge. However, this article, which sits at the intersection of public administration and organisational theory, proposes a new analytical framework for framing public-agency responses to nexus complexity. It first outlines the framework and then tests it on the case of Natural Resources Wales, the Welsh national natural environment agency. This case identifies six distinct innovations that have adopted to meet complex nexus pressures. This leads us to characterise the case as an example of a multi-scalar, hybrid, adhocratic organisation designed to meet nexus challenges. These findings have wider impact for the international community of public agencies with socio-environmental remits facing similar nexus pressures and challenges in the 21st century

Manifestations of Space-Time Multidimensionality in Scattering of Scalar Particles

We analyze a possibility of experimental detection of the contribution of the Kaluza-Klein tower of heavy particles to scattering cross-section in a six-dimensional scalar model with two dimensions being compactified to the torus with the radii $R$. It is shown that there is a noticeable effect even for the energies of colliding particles below $R^{-1}$ which may be observed in future collider experiments if $R^{-1}$ is of the order of $1 TeV$.Comment: 12 pages, LATEX, UB-ECM-PF 93/1

Local infrastructure in Australian tourist destinations: modelling tourism demand and estimating casts of water provisions and operation

With so many tourist activities in Australia, consideration must be given to the impact of the tourist on the environments in which they are located. Sustainable practices and in particular those associated with water use and wastewater production are important in planning for current tourist activity and future growth of visitors in urban and rural areas. The objectives of this research include an investigation and review of the options available to provide, operate and fund water and wastewater infrastructure to meet growing tourism needs in a sustainable manner. This has led to the development of a modelling framework for facilitating a range of analysis related to water use at Australian tourism destinations. The adopted modelling methodology includes procedures for estimating base year and forecasted tourist population at the tourist destination, water and wastewater demands associated with the visitor population, infrastructure required to satisfy water demands at the tourism region and the cost of such infrastructure provisions. This is achieved by incorporating tourist and residential population estimation for a base year and for a series of forecast future years. Population estimations are based on current and available survey data including regional tourism surveys, international and national visitor surveys and Australian census data. Water and wastewater requirements for these combined populations at the tourist destination are calculated with inclusions for irrigation based on CROPWAT software outputs. The corresponding costs of water provision and wastewater collection can then be summarised, based on the preceding estimations. To allow for application to all Australian tourism localities, the modelling process is adapted to suit data that is readily available or easily collected and involves principles that can be readily applied by the user. This methodology outlines some urban water use and wastewater production statistics across Australian capital cities, useful in later calculations. Case study applications of the model are developed for the Australian tourist destinations of Daylesford in Victoria and Byron Bay in New South Wales. Analysis includes full calculations for the water and wastewater needs and associated costs for the forecast year of 2031. Some key findings from the analysis are that for the year 2031, the costs associated with Daylesford’s residential and tourist population demand will be $32,289,650 for the total water demand and$11,128,000 for wastewater treatment. For the town of Byron Bay in 2031, these costs will be $53,601,500 for the total water demand and$18,644,000 for wastewater treatment. Major benefits of this research include better knowledge and understanding of tourist demands, and the need for water and wastewater infrastructure and analytical tools, enabling councils and other authorities to quantify present and future tourist demands, infrastructure requirements to meet demand, and the associated costs of infrastructure provision and operation

Changes in the trajectory of the radio jet in 0735+178?

We present multi-epoch 8.4 and 43 GHz Very Long Baseline Array images of the BL Lac object 0735+178. The images confirm the presence of a twisted jet with two sharp apparent bends of 90$^{\circ}$ within two milliarcseconds of the core, resembling a helix in projection. The observed twisted geometry could be the result of precession of the jet inlet, but is more likely produced by pressure gradients in the external medium through which the jet propagates. Quasi-stationary components are observed at the locations of the 90$^{\circ}$ bends, possibly produced by differential Doppler boosting. Identification of components across epochs, since the earliest VLBI observations of this source in 1979.2, proves difficult due to the sometimes large time gaps between observations. One possible identification suggests the existence of superluminal components following non--ballistic trajectories with velocities up to $11.6\pm 0.6 h_{65}^{-1} c$. However, in images obtained after mid-1995, components show a remarkable tendency to cluster near several jet positions, suggesting a different scenario in which components have remained nearly stationary in time at least since mid-1995. Comparison with the earlier published data, covering more than 19 years of observations, suggests a striking qualitative change in the jet trajectory sometime between mid-1992 and mid-1995, with the twisted jet structure with stationary components becoming apparent only at the later epochs. This would require a re-evaluation of the physical parameters estimated for 0735+178, such as the observing viewing angle, the plasma bulk Lorentz factor, and those deduced from these.Comment: 18 pages, 5 figures, accepted for publication in MNRA

Effects of intraarticular IL1-Ra for acute anterior cruciate ligament knee injury: a randomized controlled pilot trial (NCT00332254)

SummaryObjectiveTo evaluate the clinical effectiveness of intraarticular IL-1 receptor antagonist (IL-1Ra) for anterior cruciate ligament (ACL) tear.MethodsEleven patients with acute ACL tear confirmed by magnetic resonance imaging (MRI) were randomized to receive a single intraarticular injection of IL-1Ra (anakinra 150 mg, n = 6) or equal volume of saline placebo (1 ml, n = 5). The double-blinded treatment was administered a mean 2 weeks after injury. Synovial fluid (SF) (n = 9 patients) and sera (all patients) were available at baseline (prior to injection) and immediately prior to surgery (mean 35 days later) and analyzed for SF IL-1α, IL-1β, IL-1Ra and serum hyaluronan (HA), an indicator of synovial inflammation. The primary outcome, standardized Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire, was obtained at 0 (baseline), 4, and 14 days after injection.ResultsCompared with placebo, the IL-1Ra group had substantially greater improvement in key outcomes over 14 days (KOOS pain P = 0.001; activities of daily living P = 0.0015; KOOS sports function P = 0.0026; KOOS quality of life (QOL) P = 0.0048; and total KOOS P < 0.0001). There were no adverse reactions in either group. SF IL-1α (P = 0.05) and serum HA (P = 0.03), but not IL-1β, or IL-1Ra, decreased significantly in the IL-1Ra but not the placebo treated patients. Compared with placebo, IL-1α was borderline significantly different in the IL-1Ra treated group (P = 0.06).ConclusionsAdministered within the first month following severe knee injury, IL-1Ra reduced knee pain and improved function over a 2-week interval. This promising proof of concept study provides a new paradigm for studies of acute joint injury and suggests that a larger follow-up study is warranted

Current rectification by simple molecular quantum dots: an ab-initio study

We calculate a current rectification by molecules containing a conjugated molecular group sandwiched between two saturated (insulating) molecular groups of different length (molecular quantum dot) using an ab-initio non-equilibrium Green's function method. In particular, we study S-(CH2)m-C10H6-(CH2)n-S dithiol with Naphthalene as a conjugated central group. The rectification current ratio ~35 has been observed at m = 2 and n = 10, due to resonant tunneling through the molecular orbital (MO) closest to the electrode Fermi level (lowest unoccupied MO in the present case). The rectification is limited by interference of other conducting orbitals, but can be improved by e.g. adding an electron withdrawing group to the naphthalene.Comment: 8 pages, 9 figure

Noncommutative gravity: fuzzy sphere and others

Gravity on noncommutative analogues of compact spaces can give a finite mode truncation of ordinary commutative gravity. We obtain the actions for gravity on the noncommutative two-sphere and on the noncommutative ${\bf CP}^2$ in terms of finite dimensional $(N\times N)$-matrices. The commutative large $N$ limit is also discussed.Comment: LaTeX, 13 pages, section on CP^2 added + minor change

Superfield theory and supermatrix model

We study the noncommutative superspace of arbitrary dimensions in a systematic way. Superfield theories on a noncommutative superspace can be formulated in two folds, through the star product formalism and in terms of the supermatrices. We elaborate the duality between them by constructing the isomorphism explicitly and relating the superspace integrations of the star product Lagrangian or the superpotential to the traces of the supermatrices. We show there exists an interesting fine tuned commutative limit where the duality can be still maintained. Namely on the commutative superspace too, there exists a supermatrix model description for the superfield theory. We interpret the result in the context of the wave particle duality. The dual particles for the superfields in even and odd spacetime dimensions are D-instantons and D0-branes respectively to be consistent with the T-duality.Comment: 1+16 pages, no figure; expanded version, references added; Convention for Clifford algebra improve

D0 Matrix Mechanics: New Fuzzy Solutions at Large N

We wish to consider in this report the large N limit of a particular matrix model introduced by Myers describing D-brane physics in the presence of an RR flux background. At finite N, fuzzy spheres appear naturally as non-trivial solutions to this matrix model and have been extensively studied. In this report, we wish to demonstrate several new classes of solutions which appear in the large N limit, corresponding to the fuzzy cylinder,the fuzzy plane and a warped fuzzy plane. The latter two solutions arise from a possible "central extension" to our model that arises after we account for non-trivial issues involved in the large N limit. As is the case for finite N, these new solutions are to be interpreted as constituent D0-branes forming D2 bound states describing new fuzzy geometries.Comment: revised version: references added, derivation of "central extensions" improved upon. To appear in JHE