Recolonisation of lagoon of islands, Tasmania, by Baumea Arthrophylla: the first step in regeneration of a unique ecosystem?

Lagoon of Islands was a unique ecosystem. Damming the lagoon in 1964 caused the decline of the ecosystem, destroying the original vegetation and, eventually, rendering the lagoon eutrophic. While this took place the lagoon was colonised by a macrophyte not previously noticed in the lagoon. In an effort to restore acceptable water quality, restoration of macrophyte cover was encouraged by hydrological manipulation. Recent investigations have revealed that one of the original dominant macrophyte species is recolonising the lagoon, creating an alternative management option for the lagoon.

One-step synthesis of AlN branched nanostructures by an improved DC arc discharge plasma method

Aluminium nitride (AlN) branched nanostructures with tree shapes and sea urchin shapes are synthesized via a one-step improved DC arc discharge plasma method without any catalyst and template. The branched nanostructures with tree shapes and sea urchin shapes can be easily controlled by the location of collection. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies show that the branches of tree shaped nanostructures grow in a sequence of nanowires, nanomultipeds and nanocombs. The growth mechanisms of these branched nanostructures are discussed in detail. The optical properties of AlN branched nanostructures with tree shapes and sea urchin shapes are investigated.

Robust, electro-conductive, self-healing superamphiphobic fabric prepared by one-step vapour-phase polymerisation of poly(3,4-ethylenedioxythiophene) in the presence of fluorinated decyl polyhedral oligomeric silsesquioxane and fluorinated alkyl silane

A robust, electrically conductive, superamphiphobic fabric was prepared by vapour-phase polymerisation of 3,4-ethylenedioxythiophene (EDOT) on fabric in the presence of fluorinated decyl polyhedral oligomeric silsesquioxane (FD-POSS) and a fluorinated alkyl silane (FAS). The coated fabric had contact angles of 169° and 156° respectively to water and hexadecane, and a surface resistance in the range of 0.8–1.2 kΩ o⁻¹ . The incorporation of FD-POSS and FAS into the PEDOT layer showed a very small influence on the conductivity but improved the washing and abrasion stability considerably. The coated fabric can withstand at least 500 cycles of standard laundry and 10000 cycles of abrasion without apparently changing the superamphiphobicity, while the conductivity only had a small reduction after the washing and abrasion. More interestingly, the coating had a self-healing ability to auto-repair from chemical damages to restore the liquid repellency.

Robust, self-healing superamphiphobic fabrics prepared by two-step coating of fluoro-containing polymer, fluoroalkyl silane, and modified silica nanoparticles

A robust, superamphiphobic fabric with a novel self-healing ability to autorepair from chemical damage is prepared by a two-step wet-chemistry coating technique using an easily available material system consisting of poly(vinylidene fluoride-co-hexafluoropropylene), fluoroalkyl silane, and modified silica nanoparticles. The coated fabrics can withstand at least 600 cycles of standard laundry and 8000 cycles of abrasion without apparently changing the superamphiphobicity. The coating is also very stable to strong acid/base, ozone, and boiling treatments. After being damaged chemically, the coating can restore its super liquid-repellent properties by a short-time heating treatment or room temperature ageing. This simple but novel and effective coating system may be useful for the development of robust protective clothing for various applications.

Can a motivational intervention overcome an unsupportive environment for walking : findings from the step-by-step study

Background : Interventions to promote walking have rarely examined how their effects varied by the attributes of the physical environment.

Purpose : The purpose of this study is to examine whether perceptions of environmental walkability predicted change in walking behavior following an individual-based intervention to promote walking and whether the intervention buffered the effects of unsupportive environment for walking.

Methods : Inactive adults (aged 30–65 years, 85% women) who completed a 3-month randomized control trial comparing the effect of a single mail-out of a theoretically based self-help walking program (WP, n = 102); the same program plus a pedometer (WPP, n = 105); and a “no-treatment” control group (C, n = 107). Measures included change in self-reported walking time for all purposes and in the proportion of people reporting regular walking (i.e., ≥150 min/week and ≥5 sessions/wk). Perceptions of environmental esthetics, safety from crime, proximity to destinations, access to walking facilities, traffic, streetlights, connectivity, and hilliness were assessed at baseline and dichotomized into “low” or “high” by the median score. Covariates were social support, self-efficacy, intention to change behavior, and sociodemographic characteristics.

Results : Adjusting for baseline walking, significant covariates, and study groups, walking time at follow-up was lower if streetlights or esthetics were perceived to be “low” (−24% and −22%, respectively) compared with “high” (p < 0.05). In “low” esthetic conditions, those in the WPP were significantly more likely than controls to increase total walking time (Exp (b) = 2.53, p < 0.01) and to undertake regular walking (OR = 5.85, 95% CI 2.60–12.2), whereas in esthetically pleasing environments, the between-group differences were nonsignificant.

Conclusions : Walkability attributes can influence individual-based walking programs. Some environmental barriers for walking can be overcome by motivational aids.

Single step preparation of meso-porous and reduced graphene oxide by gamma-ray irradiation in gaseous phase

A facile and highly efficient route to produce simultaneously porous and reduced graphene oxide by gamma ray irradiation in hydrogen is here demonstrated. Narrowly distributed nano-scale pores (average size of ∼3 nm and surface density >44,900 pore μm-2) were generated across 10 μm thick graphene oxide bucky-papers at a total irradiation dose of 500 kGy. The graphene oxide sheet reduction was confirmed to occur homogeneously across the structures by Fourier transform infrared spectroscopy and Raman analysis. This one-step, catalyst-free, high penetration and through-put technique, offers great promises potential for the mass production of reduced graphene oxide from cheap graphene oxide. © 2013 Elsevier Ltd. All rights reserved.

Step by step analyzing, modeling and simulation of single and double array PV system in different environmental variability

This research analyses the mathematical model of the PV array with all the parameters involved, in the sequential steps. Then it is going to simulate the I-V and P-V characteristics of PV array in different climatology conditions, by using both MATLAB M-file and Simulink. Finally the capability of this method is demonstrated in simulated results, which are performed for both Single and Double Array PV system.

Effects of approach velocity and foot-target characteristics on the visual regulation of step length

Two questions emerge from the literature concerning the perceptual-motor processes underlying the visual regulation of step length. The first concerns the effects of velocity on the onset of visual control (VCO), when visual regulation of step length begins during goal-directed locomotion. The second concerns the effects of different obstacles such as a target or raised surface on step length regulation. In two separate experiments, participants (Experiment 1 & 2: n=12, 6 female, 6 male) walked, jogged, or sprinted towards an obstacle along a 10 m walkway, consisting of two marker-strips with alternating black and white 0.50 m markings. Each experiment consisted of three targeting or obstacle tasks with the requirement to both negotiate and continue moving (run-through) through the target. Five trials were conducted for each task and approach speed, with trials block randomised between the six participants of each gender. One 50 Hz video camera panned and filmed each trial from an elevated position, adjacent to the walkway. Video footage was digitized to deduce the gait characteristics. Results for the targeting tasks indicate a linear relationship between approach velocity and accuracy of final foot placement (r=0.89). When foot placement was highly constrained by the obstacle step length shortened during the entire approach. VCO was found to occur at an earlier tau-margin for lower approach velocities for both experiments, indicating that the optical variable ‘tau' is affected by approach velocity. A three-phase kinematic profile was found for all tasks, except for the take-off board condition when sprinting. Further research is needed to determine whether this velocity affect on VCO is due to ‘whole-body' approach velocity or whether it is a function of the differences between gait modes.

The effects of target length on the visual control of step length for hard and soft impacts

Adjustments to gait were examined when positioning the foot within a narrow target at the end of an approach for two impact conditions, hard and soft. Participants (6 M, 6 F) ran toward a target of three lengths along a 10-m walkway consisting of two marker strips with alternating black and white 0.5-m markings. Five trials were conducted for each target length and impact task, with trials block randomized between the 6 participants of each gender. A 50-Hz digital video camera panned and filmed each trial from an elevated position adjacent to the walkway. Video footage was digitized to deduce the gait characteristics. A linear speed/accuracy tradeoff between target length and approach time was found for both impact tasks (hard, r = 0.99, p < 0.01; soft, r = 0.96, p < 0.05). For the hard-impact task, visual control time increased linearly (r = 0.99, p < 0.05) when whole-body approach velocity decreased. Visual control time was unaffected by whole-body approach velocity in the soft-impact task. A constant tau-margin of 1.08 describes the onset of visual control when approaching a target while running, with the control of braking during visual control described by a tau-dot of –0.85. Further research is needed to examine the control of braking in different targeting tasks.

Program management: the next step in the evolution of project management?

The term ‘program management’, while referred to occasionally in journals, organisation publications and by training consultants, is not a widely acknowledged notion. While literature on project management is plentiful and the concept is well entrenched in both a practical and academic
sense, program management is a term that is used differently by various sectors. Its meaning is less defined and more broadly applied than that of project management. For example, although Program Managers are sometimes recruited under that title, the definition still remains somewhat
obscure. Seen mostly in the health and education public sectors, program management is commonly thought of as separate to project management but, as this paper will suggest, program management is more likely an extension of project management and a complementary tool to achieving
organisational outcomes. This paper attempts to clarify the distinctions between the management approaches by looking at existing literature and comparing it to common practice in a government instrumentality. It will become apparent that further research is needed regarding this significant
step in the evolution of management practices.

'Green' treatment of acid mine drainage - a step towards sustainability

Sustainability is becoming increasingly important in the mining and mineral processing industries and must incorporate the associated waste products. Acid mine drainage (AMD) is one such by-product and is one of the most serious environmental problems facing the minerals industry today. The oxidation of sulphidic mine wastes often continues for a substantial period of time after mine closure, resulting in difficult and costly remediation and rehabilitation works. Mining companies are often reluctant to spend increasing amounts of money on waste treatment when the mine life is limited or even finished. Hence a simple, low maintenance and low-cost method of treating AMD is required. Whilst this paper does not address the issue of AMD, it does propose methods for removal of individual species from AMD with potential benefits, including raising AMD pH.

A novel concept of using biosolids as a biological adsorbent, or ‘biosorbent’, of metals from AMD is being investigated at a laboratory/pilot scale level. Biosolids are a by-product resulting from the biological treatment of wastewater, and have been previously shown to adsorb metals from aqueous solutions. This could lead to an environmentally sustainable or ‘green’ method for treating both AMD discharges and disposing/reusing the biosolids.

The result of a laboratory-scale study of the biosorption of Zn(II) is presented in this paper. Physical parameters including reaction kinetics, mixing speed and solution pH were investigated. Solution pH also rose an average of 2 pH units over the 24 hour equilibrium time – a valuable side effect when treating acid mine drainage. The outcome of the study highlights the usefulness of biosolids as a biosorbent for the removal/recovery of metal ions from acid mine drainage. A simple, low-cost treatment technology requiring low maintenance would be beneficial to the mining industry to address some issues relating to AMD and would help integrate environmental and economic considerations into sustainable environmental management.

Bayesian classification of catchments using spatial data: a first step to improved modelling of catchment effects on stream ecological condition

A major challenge facing freshwater ecologists and managers is the development of models that link stream ecological condition to catchment scale effects, such as land use. Previous attempts to make such models have followed two general approaches. The bottom-up approach employs mechanistic models, which can quickly become too complex to be useful. The top-down approach employs empirical models derived from large data sets, and has often suffered from large amounts of unexplained variation in stream condition.

We believe that the lack of success of both modelling approaches may be at least partly explained by scientists considering too wide a breadth of catchment type. Thus, we believe that by stratifying large sets of catchments into groups of similar types prior to modelling, both types of models may be improved. This paper describes preliminary work using a Bayesian classification software package, ‘Autoclass’ (Cheeseman and Stutz 1996) to create classes of catchments within the Murray Darling Basin based on physiographic data.

Autoclass uses a model-based classification method that employs finite mixture modelling and trades off model fit versus complexity, leading to a parsimonious solution. The software provides information on the posterior probability that the classification is ‘correct’ and also probabilities for alternative classifications. The importance of each attribute in defining the individual classes is calculated and presented, assisting description of the classes. Each case is ‘assigned’ to a class based on membership probability, but the probability of membership of other classes is also provided. This feature deals very well with cases that do not fit neatly into a larger class. Lastly, Autoclass requires the user to specify the measurement error of continuous variables.

Catchments were derived from the Australian digital elevation model. Physiographic data werederived from national spatial data sets. There was very little information on measurement errors for the spatial data, and so a conservative error of 5% of data range was adopted for all continuous attributes. The incorporation of uncertainty into spatial data sets remains a research challenge.

The results of the classification were very encouraging. The software found nine classes of catchments in the Murray Darling Basin. The classes grouped together geographically, and followed altitude and latitude gradients, despite the fact that these variables were not included in the classification. Descriptions of the classes reveal very different physiographic environments, ranging from dry and flat catchments (i.e. lowlands), through to wet and hilly catchments (i.e. mountainous areas). Rainfall and slope were two important discriminators between classes. These two attributes, in particular, will affect the ways in which the stream interacts with the catchment, and can thus be expected to modify the effects of land use change on ecological condition. Thus, realistic models of the effects of land use change on streams would differ between the different types of catchments, and sound management practices will differ.

A small number of catchments were assigned to their primary class with relatively low probability. These catchments lie on the boundaries of groups of catchments, with the second most likely class being an adjacent group. The locations of these ‘uncertain’ catchments show that the Bayesian classification dealt well with cases that do not fit neatly into larger classes.

Although the results are intuitive, we cannot yet assess whether the classifications described in this paper would assist the modelling of catchment scale effects on stream ecological condition. It is most likely that catchment classification and modelling will be an iterative process, where the needs of the model are used to guide classification, and the results of classifications used to suggest further refinements to models.