Dielectrophoretic separation of Lactobacillus acidophillus bacteria from Saccharomyces cerevisiae yeasts

We show the size-based separation of model Saccharomyces cerevisiae yeast cells from a background of Lactobacillus acidophillus bacteria under the combined effect of dielectrophoretic (DEP) and hydrodynamic forces. © 2012 IEEE.

A simple and effective method to ameliorate the interfacial properties of cellulosic fibre based bio-composites using poly (ethylene glycol) based amphiphiles

In order to overcome interfacial incompatibility issues in natural fibre reinforced polymer bio-composites, surface modifications of the natural fibres using complex and environmentally unfriendly chemical methods is necessary. In this paper, we demonstrate that the interfacial properties of cellulose-based bio-composites can be tailored through surface adsorption of polyethylene glycol (PEG) based amphiphilic block copolymers using a greener alternative methodology. Mixtures of water or water/acetone were used to form amphiphilic emulsions or micro-crystal suspensions of PEG based amphiphilic block copolymers, and their deposition from solution onto the cellulosic substrate was carried out by simple dip-coating. The findings of this study evidence that, by tuning the amphiphilicity and the type of building blocks attached to the PEG unit, the flexural and dynamic thermo-mechanical properties of cellulose-based bio-composites comprised of either polylactide (PLA) or high density polyethylene (HDPE) as a matrix, can be remarkably enhanced. The trends, largely driven by interfacial effects, can be ascribed to the combined action of the hydrophilic and hydrophobic components of these amphiphiles. The nature of the interactions formed across the fibre-matrix interface is discussed. The collective outcome from this study provides a technological template to significantly improve the performance of cellulose-based bio-composite materials.

Feasibility of conducting a palliative care randomized controlled trial in children with advanced cancer: assessment of the PediQUEST study

Pediatric palliative care randomized controlled trials (PPC-RCTs) are uncommon.

An improved understanding of the dispersion of multi-walled carbon nanotubes in non-aqueous solvents

The homogeneous and stable dispersion of carbon nanotubes (CNTs) in solvents is often a prerequisite for their use in advanced materials. Dispersion procedures, reagent concentration as well as the interactions among reagent, defective CNTs and near-perfect CNTs will affect the resulting CNT dispersion properties. This study, for the first time, presents a detailed comparison between two different approaches for dispersing CNTs. The results enhance our understanding of the interactions between surfactant, defective CNTs and near-perfect CNTs and thus provide insight into the mechanism of CNT dispersion. Dispersions of "as-produced" short multi-walled carbon nanotubes (MWCNTs) in N,N-dimethylformamide were prepared by two different surfactant (Triton X-100) assisted methods: ultrasonication and ultrasonication followed by centrifugation, decanting the supernatant and redispersing the precipitate. Visual observation and UV-visible spectroscopy results showed that the latter method produce a more stable dispersion with higher MWCNT content compared to dispersions produced by ultrasonication alone. Transmission electron microscopy and Raman spectroscopic investigations revealed that the centrifugation/ decanting step removed highly defective nanotubes, amorphous carbon and excess surfactant from the readily re-dispersible near-perfect CNT precipitate. This is contrary to other published findings where the dispersed MWCNTs were found in the supernatant. Thermogravimetric analysis showed that 95 % of Triton X-100 was removed by centrifugation/decanting step, and the remainder of the Triton X-100 molecules is likely randomly adsorbed onto the MWCNT surface. Infrared spectral analysis suggests that the methylene groups of the polyoxyethylene (aliphatic ether) chains of the residual Triton X-100 molecules are interacting with the MWCNTs. © 2014 Springer Science+Business Media.

A C-DBSCAN algorithm for determining bus-stop locations based on taxi GPS data

Determining suitable bus-stop locations is critical in improving the quality of bus services. Previous studies on selecting bus stop locations mainly consider environmental factors such as population density and traffic conditions, seldom of them consider the travel patterns of people, which is a key factor for determining bus-stop locations. In order to draw people’s travel patterns, this paper improves the density-based spatial clustering of applications with noise (DBSCAN) algorithm to find hot pick-up and drop-off locations based on taxi GPS data. The discovered density-based hot locations could be regarded as the candidate for bus-stop locations. This paper further utilizes the improved DBSCAN algorithm, namely as C-DBSCAN in this paper, to discover candidate bus-stop locations to Capital International Airport in Beijing based on taxi GPS data in November 2012. Finally, this paper discusses the effects of key parameters in C-DBSCAN algorithm on the clustering results. Keywords Bus-stop locations, Public transport service, Taxi GPS data, Centralize density-based spatial clustering of applications with noise.

Paediatric leukaemia DNA methylation profiling using MBD enrichment and SOLiD sequencing on archival bone marrow smears

BACKGROUND: Acute Lymphoblastic Leukaemia (ALL) is the most common cancer in children. Over the past four decades, research has advanced the treatment of this cancer from a less than 60% chance of survival to over 85% today. The causal molecular mechanisms remain unclear. Here, we performed sequencing-based genomic DNA methylation profiling of eight paediatric ALL patients using archived bone marrow smear microscope slides. FINDINGS: SOLiD™ sequencing data was collected from Methyl-Binding Domain (MBD) enriched fractions of genomic DNA. The primary tumour and remission bone marrow sample was analysed from eight patients. Four patients relapsed and the relapsed tumour was analysed. Input and MBD-enriched DNA from each sample was sequenced, aligned to the hg19 reference genome and analysed for enrichment peaks using MACS (Model-based Analysis for ChIP-Seq) and HOMER (Hypergeometric Optimization of Motif EnRichment). In total, 3.67 gigabases (Gb) were sequenced, 2.74 Gb were aligned to the reference genome (average 74.66% alignment efficiency). This dataset enables the interrogation of differential DNA methylation associated with paediatric ALL. Preliminary results reveal concordant regions of enrichment indicative of a DNA methylation signature. CONCLUSION: Our dataset represents one of the first SOLiD™MBD-Seq studies performed on paediatric ALL and is the first to utilise archival bone marrow smears. Differential DNA methylation between cancer and equivalent disease-free tissue can be identified and correlated with existing and published genomic studies. Given the rarity of paediatric haematopoietic malignancies, relative to adult counterparts, our demonstration of the utility of archived bone marrow smear samples to high-throughput methylation sequencing approaches offers tremendous potential to explore the role of DNA methylation in the aetiology of cancer.

East and West, past and present: rekindle old principles for new management practices

This paper explores the sayings and stories of the ancient Chinese philosophers Guanzi, Hanfeizi, Xunzi and Yanzi. Their way of ruling the state and managing the people are analysed and discussed in line with thoughts from the mainstream and modern Western management gurus, such as Warren Bennis, Peter Drucker, Mary Parker Follett, Douglas McGregor, Rosabeth Moss Kanter, Elton Mayo, and Jeffrey Pfeffer. Striking similarities call for addressing key issues in human resource management. East and west thinkers across 3000 years are identified. The principles-based ruling and management were found difficult to be taken seriously in ancient times as it is today. However, these principles must be rekindled to protect organisations and the world from mischievous behaviour that has caused much human suffering.

What influences the beliefs, behaviours and consumption patterns of 'moderate risk' gamblers?

Gambling is emerging as a significant health issue. Problem gambling does not develop instantaneously and is often the result of risky consumption patterns over a period of time. Early intervention strategies depend on a detailed understanding of ‘at risk’ gamblers, yet surprisingly little is known about this group. This qualitative study explores the beliefs, behaviours, risk perceptions, and consumption patterns of 35 individuals who were screened as having ‘moderate risk’ gambling behaviours. Two thirds of participants gambled at least once a week and most consumed multiple types of gambling products. Participants gambled for social or emotional reasons, with many using gambling as a mechanism to socially connect and interact with others. Perceptions of behavioural control led many to believe that they were not at risk or could control gambling risks. Understanding the range of drivers that influence gambling risk is essential in developing prevention and harm minimisation strategies.

Economic evaluation of a psychological intervention for high distress cancer patients and carers: costs and quality-adjusted life years

OBJECTIVE: This study compared the cost-effectiveness of a psychologist-led, individualised cognitive behavioural intervention (PI) to a nurse-led, minimal contact self-management condition for highly distressed cancer patients and carers.

METHODS: This was an economic evaluation conducted alongside a randomised trial of highly distressed adult cancer patients and carers calling cancer helplines. Services used by participants were measured using a resource use questionnaire, and quality-adjusted life years were measured using the assessment of quality of life - eight-dimension - instrument collected through a computer-assisted telephone interview. The base case analysis stratified participants based on the baseline score on the Brief Symptom Inventory. Incremental cost-effectiveness ratio confidence intervals were calculated with a nonparametric bootstrap to reflect sampling uncertainty. The results were subjected to sensitivity analysis by varying unit costs for resource use and the method for handling missing data.

RESULTS: No significant differences were found in overall total costs or quality-adjusted life years (QALYs) between intervention groups. Bootstrapped data suggest the PI had a higher probability of lower cost and greater QALYs for both carers and patients with high distress at baseline. For patients with low levels of distress at baseline, the PI had a higher probability of greater QALYs but at additional cost. Sensitivity analysis showed the results were robust.

CONCLUSIONS: The PI may be cost-effective compared with the nurse-led, minimal contact self-management condition for highly distressed cancer patients and carers. More intensive psychological intervention for patients with greater levels of distress appears warranted.

Patient and carer identified factors which contribute to safety incidents in primary care: a qualitative study

BACKGROUND: Patients can have an important role in reducing harm in primary-care settings. Learning from patient experience and feedback could improve patient safety. Evidence that captures patients' views of the various contributory factors to creating safe primary care is largely absent. The aim of this study was to address this evidence gap. METHODS: Four focus groups and eight semistructured interviews were conducted with 34 patients and carers from south-east Australia. Participants were asked to describe their experiences of primary care. Audio recordings were transcribed verbatim and specific factors that contribute to safety incidents were identified in the analysis using the Yorkshire Contributory Factors Framework (YCFF). Other factors emerging from the data were also ascertained and added to the analytical framework. RESULTS: Thirteen factors that contribute to safety incidents in primary care were ascertained. Five unique factors for the primary-care setting were discovered in conjunction with eight factors present in the YCFF from hospital settings. The five unique primary care contributing factors to safety incidents represented a range of levels within the primary-care system from local working conditions to the upstream organisational level and the external policy context. The 13 factors included communication, access, patient factors, external policy context, dignity and respect, primary-secondary interface, continuity of care, task performance, task characteristics, time in the consultation, safety culture, team factors and the physical environment. DISCUSSION: Patient and carer feedback of this type could help primary-care professionals better understand and identify potential safety concerns and make appropriate service improvements. The comprehensive range of factors identified provides the groundwork for developing tools that systematically capture the multiple contributory factors to patient safety.

The establishment and development of neurosurgery services in Papua New Guinea

BACKGROUND: Papua New Guinea (PNG) is a developing Pacific Nation of 7.3 million people. Although neurosurgery training was introduced to PNG in the year 2000, it was in 2003 that a neurosurgery service was established. Prior to this time, neurosurgery in PNG was performed by general surgeons, with some assistance from visiting Australian neurosurgeons. Neurosurgical training was introduced to PNG in 2000. The model involved a further 3 years of training for a surgeon who had already completed 4 years of general surgical training. We aim to review the output, outcomes and impact achieved by training the first national neurosurgeon. METHODS: The data on activity (output) and outcomes were collected prospectively from 2003-2012. Ongoing mentoring and continuing professional development were provided through annual neurosurgical visits from Australia. There were serious limitations in the provision of equipment, with a lack of computerized tomographic or MR imaging, and adjuvant oncological services. RESULTS: There were 1618 neurosurgery admissions, 1020 neurosurgical procedures with a 5.74 % overall mortality. Seventy percent of cases presented as emergencies. There were improved outcomes, particularly for head injuries, whilst hydrocephalus was managed with an acceptable morbidity and revision rate. CONCLUSIONS: The training of a neurosurgeon resulted in PNG patients receiving a better range of surgical services, with a lower mortality. The outcomes able to be delivered were limited by late presentations of patients and lack of resources including imaging. These themes are familiar to all low- and middle-income countries (LMICs) and this may serve as a model for other LMIC neurosurgical services to adopt as they consider whether to establish and develop neurosurgical and other sub-specialist surgical services.

Dietary micronutrients and in vivo n-3 LC-PUFA biosynthesis in Atlantic salmon

Aquaculture, and in particular Atlantic salmon culture, is expected to deliver n. -3 long-chain polyunsaturated fatty acid (n. -3 LC-PUFA) rich products. Nevertheless, the availability of n. -3 LC-PUFA rich raw materials for aquafeed is dwindling, and at an ever increasing market price. Thus, there is the need to better understand the in vivo n. -3 LC-PUFA biosynthetic capabilities of cultured fish to enable the possible maximization of dietary 18:3n. -3 (ALA) bioconversion to 20:5n. -3 (EPA) and 22:6n. -3 (DHA). The cofactors and coenzymes involved in this metabolic pathway have so far received limited research attention. In this study, juvenile Atlantic salmon were fed an ALA-rich diet with no, normal, or over-fortified inclusion of those micronutrients reported to be essential cofactors (iron; zinc; magnesium) and coenzymes (riboflavin; biotin; niacin) for the fatty acid elongase and desaturase enzymes. The results showed that reduced dietary inclusion of these micronutrients impaired the normal n. -3 LC-PUFA biosynthetic capabilities of fish, whereas the over fortification did not provide any additional benefit. This study provides new knowledge on micronutrients and lipid metabolism interactions in a commercially important cultured species, and is envisaged to be a useful contribution towards developing more sustainable and commercially viable aquafeed for the future.Statement of relevance. This work is the continuation and extension of a previous study (Lewis et al., 2013, Aquaculture 412/413, 215-222) in which we explored the physiological roles and potential effects of micronutrients on fatty acid metabolism in cultured fish. The present study differed from the previous in the blend of minerals and vitamins used, the species, the fatty acid composition of the test diet, and the inclusion also of a negative control. The results are most interesting, showing that riboflavin (B2), biotin (B7), and niacin (B3), Iron (Fe), Magnesium (Mg) and Zinc (Zn) are all required for proper fatty acid bioconversion, but also that a dietary over-fortification does not translate into proportional improved bioconversion.

Sedimentary factors are key predictors of carbon storage in SE Australian saltmarshes

Although coastal vegetated ecosystems are widely recognised as important sites of long-term carbon (C) storage, substantial spatial variability exists in quantifications of these ‘blue C’ stocks. To better understand the factors behind this variability we investigate the relative importance of geomorphic and vegetation attributes to variability in the belowground C stocks of saltmarshes in New South Wales (NSW), southeast Australia. Based on the analysis of over 140 sediment cores, we report mean C stocks in the surface metre of sediments (mean ± SE = 164.45 ± 8.74 Mg C ha−1) comparable to global datasets. Depth-integrated stocks (0–100 cm) were more than two times higher in fluvial (226.09 ± 12.37 Mg C ha−1) relative to marine (104.54 ± 7.11) geomorphic sites, but did not vary overall between rush and non-rush vegetation structures. More specifically, sediment grain size was a key predictor of C density, which we attribute to the enhanced C preservation capacity of fine sediments and/or the input of stable allochthonous C to predominantly fine-grained, fluvial sites. Although C density decreased significantly with sediment depth in both geomorphic settings, the importance of deep C varied substantially between study sites. Despite modest spatial coverage, NSW saltmarshes currently hold approximately 1.2 million tonnes of C in the surface metre of sediment, although more C may have been returned to the atmosphere through habitat loss over the past approximately 200 years. Our findings highlight the suitability of using sedimentary classification to predict blue C hotspots for targeted conservation and management activities to reverse this trend.

Seventy years of continuous encroachment substantially increases 'blue carbon' capacity as mangroves replace intertidal salt marshes

Shifts in ecosystem structure have been observed over recent decades as woody plants encroach upon grasslands and wetlands globally. The migration of mangrove forests into salt marsh ecosystems is one such shift which could have important implications for global 'blue carbon' stocks. To date, attempts to quantify changes in ecosystem function are essentially constrained to climate-mediated pulses (30 years or less) of encroachment occurring at the thermal limits of mangroves. In this study, we track the continuous, lateral encroachment of mangroves into two south-eastern Australian salt marshes over a period of 70 years and quantify corresponding changes in biomass and belowground C stores. Substantial increases in biomass and belowground C stores have resulted as mangroves replaced salt marsh at both marine and estuarine sites. After 30 years, aboveground biomass was significantly higher than salt marsh, with biomass continuing to increase with mangrove age. Biomass increased at the mesohaline river site by 130 ± 18 Mg biomass km-2 yr-1 (mean ± SE), a 2.5 times higher rate than the marine embayment site (52 ± 10 Mg biomass km-2 yr-1), suggesting local constraints on biomass production. At both sites, and across all vegetation categories, belowground C considerably outweighed aboveground biomass stocks, with belowground C stocks increasing at up to 230 ± 62 Mg C km-2 yr-1 (± SE) as mangrove forests developed. Over the past 70 years, we estimate mangrove encroachment may have already enhanced intertidal biomass by up to 283 097 Mg and belowground C stocks by over 500 000 Mg in the state of New South Wales alone. Under changing climatic conditions and rising sea levels, global blue carbon storage may be enhanced as mangrove encroachment becomes more widespread, thereby countering global warming.