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The challenges of sampling rare fauna limit efforts to understand and mitigate the factors that restrict their distribution. Camera traps have become a standard technique for sampling large mammals, but their utility for sampling small, rare species remains largely unknown. The central rock-rat ( Zyzomys pedunculatus ) is critically endangered and restricted to rugged range country in central Australia. Using Z. pedunculatus as a focal species, we sought to evaluate the effectiveness of camera trapping for sampling small mammals in this environment and to better understand the factors driving the occurrence of this species. We installed baited camera traps at 50 sites across 1795 ha of core refuge habitat for Z. pedunculatus . We recorded all six species of small mammals known previously from this area, including the highly detectable Z. pedunculatus at five sites. Occupancy modelling showed that distance to the nearest occupied site was the most important predictor of Z. pedunculatus occurrence, suggesting that this rodent occurs in discrete sub-populations within the matrix of refuge habitat. Fire history and ruggedness may also influence occupancy of Z. pedunculatus at the landscape-scale and could assist in locating additional sub-populations. At the site-scale, occupancy of Z. pedunculatus was high and there was no clear influence of any site-scale variables. Management of Z. pedunculatus will require protection and expansion of known sub-populations. We conclude that camera trapping provided useful and cost-effective insight into the factors limiting rock-rat distribution, and predict that it will become a standard tool for sampling rare small mammals in difficult-to-access environments. [ABSTRACT FROM AUTHOR]

Patch-mosaic burning is a widely accepted practical approach to managing biodiversity, whereby spatial and temporal diversity of fire is manipulated to benefit biotic diversity. We use simulation experiments based on stochastic population viability analysis to evaluate the implications of contrasting patch-mosaic burning scenarios for the population dynamics and risk of decline of four species of small mammals in northern Australia. Our results, based on models developed from detailed mark-recapture data, suggest that fire frequency has more influence on small-mammal persistence than fire extent. Risk of extinction increased for all four species when fire frequency exceeded once every five years. Under current ambient fire regimes most Australia tropical savannas burn more frequently and therefore seem to have unfavourable consequences for this faunal group and risk precipitating severe future declines. [ABSTRACT FROM AUTHOR]

Abstract: The recycling of iron bearing dusts produced during iron and steel manufacturing processes is vital to the sustainability of these processes; however, contamination of these dusts with zinc increases the difficulty to do this. Blast furnace dust, collected by a wet scrubber system, was sampled and characterised to investigate the removal of zinc to produce a treated residue with low zinc content suitable for recycling through the blast furnace. This paper examines a leaching process for the dust using different organic carboxylic acids, to establish if they were capable of extracting high levels of zinc and low levels of iron. Prop-2-enoic acid was found to be particularly effective, extracting high levels of zinc up to 85.7% and low levels of iron, 8.5%. The paper also discusses the mechanisms of extraction more specifically for organic carboxylic acids and found that the iron extraction was well explained by the variation in pH and the Bronsted–Lowry theory; whereas zinc extraction was well explained by substituent group effects and the Lewis acid/base theory. The novel use of a non-aqueous solvent with prop-2-enoic acid, to minimise the ion solvating ability and proton dissociation, was found to reduce the level of iron extraction from 8.5% to 0.1% without detrimental effect on zinc extraction when leaching. A range of mineral and carboxylic acids were also tested to investigate and compare the effect of pH and chemical structure on the leaching efficacy. [Copyright &y& Elsevier]

Abstract: Objective: The purpose of this prospective study was to record endothelin-1 (ET-1) concentrations in the second trimester amniotic fluid and compare these values in women who developed intrauterine growth restriction (IUGR) later in pregnancy with those with uneventful pregnancies. Method: Amniotic fluid was retrieved by amniocentesis from 125 women in the second trimester of pregnancy. The levels of ET1 were measured by a sensitive and specific radioimmunoassay. Results: From the 125 women included in the study 12 had pregnancies that later developed IUGR and 88 had uneventful pregnancies. The ET1 concentration was significantly higher (P <0.005) in women who later developed IUGR than in normal pregnancy (106pg/ml versus 64.7pg/ml). Conclusion: The amniotic fluid concentration of ET1 is elevated by the second trimester in women who later develop IUGR. [Copyright &y& Elsevier]

Aboriginal people in remote Australian communities have limited opportunity to participate in the market economy. The Aboriginal arts and craft industry offers an important option to generate cash income and the sustained supply of native plants used in production is vital. We assessed the current harvest of a rainforest tree species commonly used for sculpture, Bombax ceiba. Information from field surveys, a regional rainforest inventory and sales figures from the Maningrida region were used to estimate the population size and structure of B. ceiba, the harvest intensity of patches and the economic value of the harvest. We estimate the density of B. ceiba to be 105.10±12.32 stems ha−1 and a regional population of 76615±14063 stems. A cumulative harvest over 20 years of 6% suggests approximately 4596 stems harvested, and the harvest was worth about $200,000 over the last three years. The majority (80%) of harvested stems coppiced and were suitable for harvesting. Logistic regression suggests both distance to outstation and township influence harvesting intensity, with some localised over-harvest. Rainforests provide a valuable resource to Aboriginal artists in Maningrida and their maintenance provides important conservation benefits to the Australian community. [Copyright &y& Elsevier]

The group of patients who received urinary gonadotropins (n = 117) for follicular stimulation had a significantly higher incidence of high perifollicular blood flow compared with that of the group who received recombinant FSH (n = 114; 46.3% vs. 22.7%). The overall clinical pregnancy rate in patients stimulated with recombinant FSH was 10.91%, compared with 22.22% in the group stimulated with urinary gonadotropins. [ABSTRACT FROM AUTHOR]

Abstract: Vermicompost was produced from a green waste compost feedstock and assessed for its potential use in a high value horticultural market. Replicated plant growth trials were undertaken with lettuce using pure worm cast (vermicompost), green waste-derived compost and mixtures of the two, i.e. 50/50 (v/v) and 20/80 (v/v) of worm casts and green waste feedstock. Results showed that plant biomass production was optimal with a 20/80 (v/v) compost blend, whilst pure worm cast and green waste compost yielded poor growth. Leaf chlorophyll content indicated that pure worm cast inhibited plant growth and depressed N content, whereas plant grown with the other treatments contained similar amounts of chlorophyll. In general, the vermicomposting process did not result in an increased availability of nutrients or potentially toxic elements, the only exception being Zn. [Copyright &y& Elsevier]

Next-generation sequencing is now commonly used for a variety of applications in virology including virus discovery, investigation of quasispecies, viral evolution, metagenomics, and analyses of antiviral resistance. However, there are limitations with the current sample preparation methods used for deep sequencing of viral genomes, especially during de novo sequencing. For example, current methods are unable to capture the terminal sequences of viral genomes in an efficient and effective manner; data representing the 3′ and 5′ ends are typically insufficient. Methods such as Rapid Amplification of cDNA Ends address this issue but these methods can be time consuming, may require some prior knowledge of the viral sequence, and require multiple independent procedures. The current study outlines a sample preparation technique that overcomes some of these shortcomings. The method relied on random fragmentation with divalent cations and subsequent adapter ligation directly to RNA, rather than cDNA, to maximize the quality and quantity of terminal reads. The technique was tested on RNA samples from two different RNA viruses, Ebola virus and hepatitis C virus. This method permits rapid preparation of samples for deep sequencing while eliminating the use of sequence specific primers and captures the entire genome sequence, including the 5′ and 3′ ends. This could improve the efficiency of virus discovery projects where the terminal ends are unknown. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the practical combustion issues encountered with biomass co-firing on a large scale trial in a 500MW down fired utility boiler at Aberthaw power station. It also investigates and discusses the effect of biomass particle size and physical properties on devolatilisation; flame stability; and slagging by using the biomass energy crop miscanthus. During large scale biomass co-firing, the air flow around the injectors plays an important part in the fuel combustion and stable boiler operation. Secondary air flow at the point of biomass injection was adjusted during the experiments to provide higher airflows around the biomass injectors, hence the mixing, and air available for biomass combustion, was improved producing less unburnt material in the ash and reducing potential filter blockages. However, higher biomass air flows disrupt the temperature distribution in the boiler causing a wider variation of superheater temperatures compared to the baseline condition firing coal only. This reduces the combustion efficiency and can lead to localised hot spots, in the superheaters, with the potential to cause equipment damage. The trials indicated during the experiments that a secondary biomass air flow of 50% of its maximum, gave an optimum balance between air/biomass mixing and variations in the superheater temperatures. [Copyright &y& Elsevier]

Abstract: Lean premixed swirl combustion is widely used in gas turbines and many other combustion Processes due to the benefits of good flame stability and blow off limits coupled with low NO x emissions. Although flashback is not generally a problem with natural gas combustion, there are some reports of flashback damage with existing gas turbines, whilst hydrogen enriched fuel blends, especially those derived from gasification of coal and/or biomass/industrial processes such as steel making, cause concerns in this area. Thus, this paper describes a practical experimental approach to study and reduce the effect of flashback in a compact design of generic swirl burner representative of many systems. A range of different fuel blends are investigated for flashback and blow off limits; these fuel mixes include methane, methane/hydrogen blends, pure hydrogen and coke oven gas. Swirl number effects are investigated by varying the number of inlets or the configuration of the inlets. The well known Lewis and von Elbe critical boundary velocity gradient expression is used to characterise flashback and enable comparison to be made with other available data. Two flashback phenomena are encountered here. The first one at lower swirl numbers involves flashback through the outer wall boundary layer where the crucial parameter is the critical boundary velocity gradient, Gf . Values of Gf are of similar magnitude to those reported by Lewis and von Elbe for laminar flow conditions, and it is recognised that under the turbulent flow conditions pertaining here actual gradients in the thin swirl flow boundary layer are much higher than occur under laminar flow conditions. At higher swirl numbers the central recirculation zone (CRZ) becomes enlarged and extends backwards over the fuel injector to the burner baseplate and causes flashback to occur earlier at higher velocities. This extension of the CRZ is complex, being governed by swirl number, equivalence ratio and Reynolds Number. Under these conditions flashback occurs when the cylindrical flame front surrounding the CRZ rapidly accelerates outwards to the tangential inlets and beyond, especially with hydrogen containing fuel mixes. Conversely at lower swirl numbers with a modified exhaust geometry, hence restricted CRZ, flashback occurs through the outer thin boundary layer at much lower flow rates when the hydrogen content of the fuel mix does not exceed 30%. The work demonstrates that it is possible to run premixed swirl burners with a wide range of hydrogen fuel blends so as to substantially minimise flashback behaviour, thus permitting wider used of the technology to reduce NOx emissions. [Copyright &y& Elsevier]

Aerial survey methods for census of wildlife populations are widely used to manage species. There has been considerable research to develop methods to cope with imperfect detection during aerial surveys, however misidentification remains an unresolved but significant issue. Using data from a comprehensive dugong aerial survey of the coastline of the Northern Territory, Australia, we assessed the influence of observer, sighting and environmental variables on probabilities of both observers in double-count, dual-observer teams detecting dugongs and dolphins ('duplicate sighting probability'), the confidence with which observers could distinguish between dugongs and dolphins, and the reliability of post-detection observations by comparing data between observers. Dolphin duplicate sighting probability varied dependent on group size, Beaufort sea state and the lateral position inside the strip-width transect in relation to the aircraft. Dugong duplicate sighting probability varied across dual-observer teams. Counts of individuals in dugong and dolphin groups were unreliable past ≈5 individuals. Observer confidence in taxon identification varied by individual observer and throughout the duration of the survey (dolphin sightings) and potentially by the lateral position inside the transect strip-width in relation to the aircraft (dugong sightings). The probability of taxon identification disagreement between observers for duplicate dugong and dolphin sightings varied with group size, and markedly if one observer was uncertain (i.e. not 100% confident) of their assigned taxon. We believe this is predominately due to the presence of Australian snubfin dolphins (Orcaella heinsohni) in the survey area, which look like dugongs when seen from a distance, momentarily. We further show that application of different data filtering scenarios for uncertain taxonomic identifications and taxon identification disagreements between dual observers produces highly variable estimates of observer-specific dugong detection probability (ranging from 0.26 to 0.80 in a single observer) and dugong abundance (x̅ ± S.D., 40% ± 25%: difference between highest and lowest estimate, relative to the lowest estimate, across different data filtering scenarios). These results are particularly relevant not only to researchers conducting dugong aerial surveys, but also for other marine mammal aerial surveys in passing mode that target sympatric, morphologically similar species. We recommend development of operating procedures and analytical methods to quantify and adjust for misidentification and uncertain taxon identifications. • Accurate species identification (ID) and counts are essential for aerial surveys. • Species detection and accurate ID varies between observers and with other variables. • Detection & Abundance estimates vary depending on how ambiguous data are filtered. • Surveys of sympatric, morphologically similar species may be similarly affected. [ABSTRACT FROM AUTHOR]

Junin (JUNV) and Machupo (MACV), two mammalian arenaviruses placed on the 2018 WHO watch list, are prevalent in South America causing Argentine and Bolivian hemorrhagic fevers (AHF and BHF), respectively. The live attenuated JUNV vaccine, Candid #1, significantly reduced the incidence of AHF. Vaccination induces neutralizing antibody (nAb) responses which effectively target GP1 (the viral attachment glycoprotein) pocket which accepts the tyrosine residue of the cellular receptor, human transferrin receptor 1 (TfR1). In spite of close genetic relationships between JUNV and MACV, variability in the GP1 receptor binding site (e.g., MACV GP1 loop 10) results in poor MACV neutralization by Candid #1-induced nAbs. Candid #1 is not recommended for vaccination of children younger than 15 years old (a growing "at risk" group), pregnant women, or other immunocompromised individuals. Candid #1's primary reliance on limited missense mutations for attenuation, genetic heterogeneity, and potential stability concerns complicate approval of this vaccine in the US. To address these issues, we applied alphavirus RNA replicon vector technology based on the human Venezuelan equine encephalitis vaccine (VEEV) TC-83 to generate replication restricted virus-like-particles vectors (VLPVs) simultaneously expressing cellular glycoprotein precursors (GPC) of both viruses, JUNV and MACV. Resulting JV&MV VLPVs were found safe and immunogenic in guinea pigs. Immunization with VLPVs induced humoral responses which correlated with complete protection against lethal disease after challenge with pathogenic strains of JUNV (Romero) and MACV (Carvallo). [ABSTRACT FROM AUTHOR]

• Ultrafine RuNPs are stabilised by amino-modified polymer immobilized ionic liquid. • High activity for hydrolytic evolution of hydrogen from NaBH 4. • Kinetic studies confirm the hydrolysis is first order in catalyst and hydride. • Kinetic isotope studies with H 2 O/D 2 O and NaBH 4 /NaBD 4 support the proposed mechanism. • High activity retained over five reuses with only a minor reduction in conversion. Ruthenium nanoparticles stabilised by polymer immobilized ionic liquids catalyse the hydrolytic release of hydrogen from sodium borohydride. The composition of the polymer influences performance and ruthenium nanoparticles stabilised by an amine-decorated imidazolium-based polymer immobilised ionic liquid (RuNP@NH 2 -PIILS) was the most efficient with a maximum initial turnover frequency (TOF) of 177 mole H2.mol Ru −1.min−1, obtained at 30°C with a catalyst loading of 0.08 mol%; markedly higher than that of 69 mol H2.mol Ru −1.min−1 obtained with 5 wt% Ru/C and one of the highest to be reported for a RuNP catalyst. The apparent activation energy (Ea) of 38.9 kJ mol−1 for the hydrolysis of NaBH 4 catalysed by RuNP@NH 2 -PIILS is lower than that for the other polymer immobilized ionic liquid stabilised RuNPs, which is consistent with its efficacy. Comparison of the initial rates of hydrolysis in H 2 O and D 2 O catalysed by RuNP@NH 2 -PIILS gave a primary kinetic isotope effect (k H / k D) of 2.3 which supports a mechanism involving rate limiting oxidative addition of one of the O-H bonds in a strongly hydrogen-bonded surface-coordinated [BH 3 H−]—-H 2 O ensemble. The involvement of a surface-coordinated borohydride is further supported by an inverse kinetic isotope effect of 0.65 obtained from a comparison of the initial rates for the hydrolysis of NaBH 4 and NaBD 4 under the conditions of catalysis i.e., at a high hydride/catalyst mole ratio. Interestingly though, when the comparison of the initial rates of hydrolysis of NaBH 4 and NaBD 4 was conducted in dilute solution with a hydride/catalyst mole ratio of 1 a kinetic isotope effect (k H / k D) of 2.72 was obtained; this would be more consistent with concerted activation of both an O-H and B-H bond in the rate limiting step, possibly via a concerted oxidative addition-hydride transfer in the surface-coordinated hydrogen-bonded ensemble. Catalyst stability and reuse studies showed that RuNP@NH 2 -PIILS retained 71% of its activity over five runs; the gradual drop in the initial TOF with run number appears to be due to passivation of the catalyst by the sodium borate by-product as well as an increase in viscosity of the reaction mixture rather than leaching of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Hydrous ferric oxide (here termed ‘ochre’) sludge, an abundant waste product produced from the treatment of acid mine drainage (AMD), was used in this study for the removal of phosphorus (in the form of phosphate ions) from contaminated waters. The phosphorus uptake capacities of both raw and pelletized AMD solids were compared using batch and column tests. Addition of a cement binder to the AMD solids during pellet production led to significantly increased P-loading of the resultant solids compared to the raw sludge. Additionally, the pellets were found to continue to remove P in tests up to 7d in duration whereas the unbound AMD sludge appeared to approach equilibrium with phosphate solution after approximately 60min of contact time. In line with previous studies P uptake by the AMD solids was found to be primarily via adsorption. By contrast calcium phosphate precipitation was found to be the dominant removal mechanism for the cement-bound ochre pellets with a relatively small proportion of removal attributable to the AMD solids. SEM–EDX analysis of the surface of used pellets showed a Ca:P molar ratio close to that of hydroxyapatite (HAP). Continuous column tests on these pellets showed a rapid decrease in P removal capacity by the pellets over time, attributable to the formation of a passivating HAP surface layer. [Copyright &y& Elsevier]

Abstract: Producer gas is a form of synthesis gas formed from the gasification of biomass. Its composition varies largely depending on the gasifier type, up-draft, down-draft and entrained flow to name a few, and oxidiser, typically air, steam or pure oxygen. The producer gas in question is derived from an air fed down-draft gasifier containing Grade-A wood waste, and as such has comparatively low calorific value and hydrogen content of around 6MJ/Nm3 and 11% respectively. The viability of producing thermal energy on an industrial scale was proved via the swirl-stabilised combustion of forementioned producer gas in a 1.5MW rated swirl burner, directly attached to a proprietary gasification plant. A largely stable combustion was achieved; however, a few instances of flame extinction did occur which were attributed to varying fluctuations in gasifier throat temperature. A relationship between throat temperature and fuel composition is believed to be the cause of these extinctions. Although these fluctuations were shown to have little effect on the producer gases stoichiometric air-to-fuel ratio and calorific value, there was particular variance in hydrogen content. Simulation using CHEMKIN showed that this variable hydrogen content had a significant effect on flame speed, with an increase from 5% to 15% hydrogen increasing laminar flame speed from 8.01cm/s to 17.70cm/s. Industrial-scale data was also compared to that taken with a 100kW laboratory-scale combustor in an attempt to establish whether burner optimisation could be effectively achieved in a controlled laboratory environment. A relationship was found between exhaust temperature and introduction of axial air, which extended across both burners. Flame speed and flame temperature simulations also showed that air is an acceptable diluent of natural gas when substituting for producer gas. [Copyright &y& Elsevier]

Quantitative measurement of viral load is an important parameter in the management of filovirus disease outbreaks because viral load correlates with severity of disease, survival, and infectivity. During the ongoing Ebola virus disease outbreak in parts of Western Africa, most assays used in the detection of Ebola virus disease by more than 44 diagnostic laboratories yielded qualitative results. Regulatory hurdles involved in validating quantitative assays and the urgent need for a rapid Ebola virus disease diagnosis precluded development of validated quantitative assays during the outbreak. Because of sparse quantitative data obtained from these outbreaks, opportunities for study of correlations between patient outcome, changes in viral load during the course of an outbreak, disease course in asymptomatic individuals, and the potential for virus transmission between infected patients and contacts have been limited. We strongly urge the continued development of quantitative viral load assays to carefully evaluate these parameters in future outbreaks of filovirus disease. [ABSTRACT FROM AUTHOR]