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Aging of nickel added to soils as predicted by soil pH and time
No full textAlthough aging processes are important in risk assessment for metals in soils, the aging of Ni added to soils has not been studied in detail. In this study, after addition of water soluble Ni to soils, the changes over time in isotopic exchangeability, total concentrations and free Ni2+ activity in soil pore water, were investigated in 16 European soils incubated outdoors for 18 months. The results showed that after Ni addition, concentrations of Ni in soil pore water and isotopic exchangeability of Ni in soils initially decreased rapidly. This phase was followed by further decreases in the parameters measured but these occurred at slower rates. Increasing soil pH increased the rate and extent of aging reactions. Semi-mechanistic models, based on Ni precipitation/nucleation on soil surfaces and micropore diffusion, were developed and calibrated. The initial fast processes, which were attributed to precipitation/nucleation, occurred over a short time (e.g. 1 h), afterwards the slow processes were most likely controlled by micropore diffusion processes. The models were validated by comparing predicted and measured Ni aging in three additional, widely differing soils aged outdoors for periods up to 15 months in different conditions. These models could be used to scale ecotoxicological data generated in short-term studies to longer aging times.
Feasibility of omega-3 fatty acid supplementation as an adjunct therapy for people with chronic obstructive pulmonary disease : study protocol for a randomized controlled trial
No full textDiscussion: There are a number of challenges in designing supplementation intervention studies with this population. These include the lack of prior data from which to select appropriate primary outcomes or to estimate effect sizes, and the feasibility of continuous supplementation in a population characterized by multiple comorbidities and a high likelihood of exacerbations, potentially requiring hospitalization or change in medication. Upon completion of this protocol, feasibility outcomes will guide the direction of future multicentre dietary interventions in this population.
Modified quasi-OBE algorithm with improved numerical properties
No full textThe quasi-OBE (QOBE) algorithm is a set-membership adaptive filtering algorithm based on the principles of optimal bounding ellipsoid (OBE) processing. This algorithm can provide enhanced convergence and tracking performance as well as reduced average computational complexity in comparison with the more traditional adaptive filtering algorithms such as the recursive least-squares (RLS) algorithm. In this paper, we show that the QOBE algorithm is prone to numerical instability due to the unbounded growth/decay of its internal variables. To tackle this problem, we develop a new set-membership adaptive filtering algorithm by transforming QOBE's internal variables into a new set of internal variables. The new algorithm, called modified quasi-OBE (MQOBE), can be viewed as an exponentially-weighted RLS algorithm with a time-varying forgetting factor, which is optimized at each iteration by imposing a bounded-magnitude constraint on the a posteriori filter output error. The proposed algorithm delivers the same convergence and tracking performance as the QOBE algorithm but with enhanced numerical properties. We demonstrate the improved numerical behavior of the proposed algorithm by simulation examples for a MIMO channel estimation problem.
Involving juries in sentencing : insights from the Tasmanian jury study
No full textThis article reviews the findings of the Tasmanian jury sentencing study that are relevant to the debate about directly involving juries in sentencing outcomes, a debate that has been revived by a proposal to allow juries in Victoria to recommend a minimum non-parole period. The results support the conclusion of the New South Wales Law Reform Commission that proposals to involve juries directly in sentencing decisions would encounter consider- able practical and procedural problems and would raise concerns about the fairness of the process.
Conveying discrete memoryless sources over networks : when are zero-rate edges dispensable?
No full textThis work investigates the problem of conveying discrete memoryless sources over general networks with specified lossless (vanishing error probability) and/or lossy (average per-symbol distortion) reconstruction demands. It presents two different sufficient conditions under which an edge carrying zerorate messages is not crucial for the conveyance of the sources, i.e., the demands can be met even when the zero-rate edge is deleted and the rates on other edges are kept unchanged.
Sampling patterns and edge effects in a biodiversity study of urban linear streetscapes
No full textIn biodiversity monitoring programs, the selection of an unbiased sampling pattern has remained a significant challenge. This has been highlighted in systematic samplings where repeated habitat patterns may constantly occur or where over- or under-sampling of specific habitat areas may bias sampling efforts. A pilot study was designed to determine the best sampling pattern for a later full biodiversity study between bioretention swales, as a linear type of stormwater management linear system, and equivalent conventional green spaces in urban streetscapes in the Australian city of Melbourne. The sites were pitfall trapped and two spatial sampling patterns were compared to examine edge effects and the effects of regularly repeated habitat areas on invertebrate diversity in these landscapes. The number of species, Margalef’s species richness (d) and the Shannon diversity index (H’) showed non-significant differences between the two sampling patterns in any of the two landscape types of bioretention swales and conventional green spaces and in combining the landscape types. These results implied that it was experimentally valid to select any of the sampling patterns. The outcomes of this study may inform future sampling design in linear small-scale streetscapes and may support the use of pilot studies of different sampling patterns prior to finalising a sampling design.
An integrated approach for selecting biodiversity indicators in an Australian streetscape study
No full textIn an attempt to conserve and monitor biodiversity, field studies are often undertaken involving the use of biodiversity indicators. Selection of appropriate species is an integral component of the research design of such ecological programs. There are strong arguments for selecting invertebrates as a reliable biodiversity indicator but broad invertebrate assemblages are rarely used as biodiversity indicators in environmental monitoring or inventorying programs. The selection of a narrow invertebrate species grouping is often preferred but there is little researchbased evidence to justify such selection in biodiversity studies. To validate such an approach, a biodiversity study was undertaken in several linear green strip areas within urban streetscapes. These strips had a width range of 2.5 to 5 m. The sites were pitfall trapped and selection of the best invertebrate taxa group as a biodiversity indicator was investigated in summer and spring sampling regimes. In both the summer and spring surveys, the number of species (S) in the double-order of Coleoptera and Hymenoptera consistently correlated best to the total number of species of the invertebrates captured in the studied sites (R2 = 0.81 in the summer survey and R2 = 0.94 in the spring survey). The correlation was even stronger between the Shannon diversity index (H’) of Coleoptera and Hymenoptera and the Shannon diversity index of the total invertebrates of the sites (R2 = 0.96 in the summer survey and R2 = 0.83 in the spring survey). These findings suggest that for the sites investigated, Coleoptera and Hymenoptera together may be considered as surrogates for invertebrate diversity measures in these small-scale urban landscapes. The outcomes of this study reinforce that conducting pilot studies can help to validate the selected biodiversity indicator while rationalising time and effort in biodiversity monitoring. Further studies are needed to test whether the results are specific to the studied
A Drosophila Model to Image Phagosome Maturation
No full textPhagocytosis involves the internalization of extracellular material by invagination of the plasma membrane to form intracellular vesicles called phagosomes, which have functions that include pathogen degradation. The degradative properties of phagosomes are thought to be conferred by sequential fusion with endosomes and lysosomes; however, this maturation process has not been studied in vivo. We employed Drosophila hemocytes, which are similar to mammalian professional macrophages, to establish a model of phagosome maturation. Adult Drosophila females, carrying transgenic Rab7-GFP endosome and Lamp1-GFP lysosome markers, were injected with E. coli DH5α and the hemocytes were collected at 15, 30, 45 and 60 minutes after infection. In wild-type females, E. coli were detected within enlarged Rab7-GFP positive phagosomes at 15 to 45 minutes after infection; and were also observed in enlarged Lamp1-GFP positive phagolysosomes at 45 minutes.
What happens to mood, performance and sleep in a laboratory study with no sleep deprivation?
No full textThere are few studies examining changes in waking function in a laboratory environment with no sleep deprivation and mood has been largely overlooked in this context. The present study examined changes in mood, performance, sleep and sleepiness in the laboratory study with no sleep deprivation. Nineteen participants (10M, 9F; 22 ± 4.2 years) were given nine 9-h sleep opportunities (23.00–08.00 hours). Every 2 h during wake, participants completed the Mood Scale II, a 10-min Psychomotor Vigilance Task and measures of sleepiness and fatigue. Sleep was monitored using an electroencephalographic montage. Findings revealed significant negative mood change, performance impairment, reduced total sleep time and sleep efficiency (all P < 0.05). These findings suggest that the laboratory environment or procedural factors may impair mood, performance and sleep. These findings may have implications for interpreting impairments in mood, performance and sleep when observed in laboratory environments.
A monoclonal antibody against the extracellular domain of P75 neurotrophin receptor
No full textThe aim of this study was to prepare and identify a monoclonal antibody against the extracellular domain of p75 neurotrophin receptor (p75NTR-ECD), which will be used in diagnostics, therapeutics, and as a tool in understanding the role of P75NTR in pathogenesis of neuronal degenerative diseases and cancers. In this study, hybridoma technique was used for production of anti-p75NTR-ECD monoclonal antibody. BALB/c mice were immunized with p75NTR-ECD recombinant protein. Hybridoma clones were screened using indirect enzyme-linked immunosorbent assay (ELISA). Anti-p75NTR-ECD monoclonal antibody was produced by ascites revulsion. Protein A affinity chromatography was used for the purification of anti-p75NTR-ECD monoclonal antibody. Titer of anti-p75NTR-ECD was assessed by ELISA. Specificity of anti-p75NTR-ECD was detected by immunofluorescence and immunohistochemistry. As a result, one stable hybridoma cell clone (3B5F9) producing anti-p75NTR-ECD monoclonal antibody was established. The titer of anti-p75NTR-ECD monoclonal antibody is 1:51200. A 2.91 mg monoclonal antibody against p75NTR-ECD with high specificity was prepared. Immunofluorescence and immunohistochemistry showed that p75NTR-ECD positive staining occurs in the plasma membrane of glioma cell and tissue, which results in an advantage in diagnostic and therapeutic targeting of P75NTR expressing neuronal degenerative diseases and cancers.