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    Regional patterns of mtDNA diversity in Styela plicata, an invasive ascidian, from Australian and New Zealand marinas
    (CSIRO PUBLISHING, 7/03/2013) Torkkola J; Riginos C; Liggins L
    The ascidian Styela plicata is abundant in harbours and marinas worldwide and has likely reached this distribution via human-mediated dispersal. Previous worldwide surveys based on mitochondrial cytochrome oxidase one (COI) sequences have described two divergent clades, showing overlapping distributions and geographically widespread haplotypes. These patterns are consistent with recent mixing among genetically differentiated groups arising from multiple introductions from historically distinct sources. In contrast, a study of Australian S. plicata using nuclear markers found that population differentiation along the eastern coast related to geographic distance and no evidence for admixture between previously isolated genetic groups. We re-examined the genetic patterns of Australian S. plicata populations using mtDNA (CO1) to place their genetic patterns within a global context, and we examined New Zealand populations for the first time. We found that the haplotypic compositions of Australian and New Zealand populations are largely representative of other worldwide populations. The New Zealand populations, however, exhibited reduced diversity, being potentially indicative of a severely bottlenecked colonisation event. In contrast to results from nuclear markers, population differentiation of mtDNA among Australian S. plicata was unrelated to geographic distance. The discrepancy between markers is likely to be a consequence of non-equilibrium population genetic processes that typify non-indigenous species. © 2013 CSIRO.
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    Evaluating edge-of-range genetic patterns for tropical echinoderms, Acanthaster planci and Tripneustes gratilla, of the Kermadec Islands, southwest Pacific
    (ROSENSTIEL SCH MAR ATMOS SCI, 1/01/2014) Liggins L; Gleeson L; Riginos C
    Edge-of-range populations are often typified by patterns of low genetic diversity and high genetic differentiation relative to populations within the core of a species range. The "core-periphery hypothesis," also known as the "central-marginal hypothesis," predicts that these genetic patterns at the edge-of-range are a consequence of reduced population size and connectivity toward a species range periphery. It is unclear, however, how these expectations relate to high dispersal marine species that can conceivably maintain high abundance and high connectivity at their range edge. In the present study, we characterize the genetic patterns of two tropical echinoderm populations in the Kermadec Islands, the edge of their southwest Pacific range, and compare these genetic patterns to those from populations throughout their east Indian and Pacific ranges. We find that the populations of both Acanthaster planci (Linnaeus, 1758) and Tripneustes gratilla (Linnaeus, 1758) are represented by a single haplotype at the Kermadec Islands (based on mitochondrial cytochrome oxidase C subunit I). Such low genetic diversity concurs with the expectations of the "core-periphery hypothesis." Furthermore, the haplotypic composition of both populations suggests they have been founded by a small number of colonists with little subsequent immigration. Thus, local reproduction and self-recruitment appear to maintain these populations despite the ecologically marginal conditions of the Kermadec Islands for these tropical species. Understanding rates of self-recruitment vs reliance on connectivity with populations outside of the Kermadec Islands has implications for the persistence of these populations and range stability of these echinoderm species.© 2014 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.
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    Formation of nano-fibrils from the A, B and C variants of bovine beta-lactoglobulin
    (ELSEVIER SCI LTD, 1/02/2015) Dave, AC; Loveday, SM; Anema, SG; Jameson, GB; Singh, H
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    Experiences of nursing in older care facilities in New Zealand
    (CSIRO Publishing, 2010) Carryer JB; Hansen C; Blakey JA
    To examine issues related to the working life of registered nurses in residential care for older people in New Zealand, 48 registered nurses completed surveys (n = 28) or participated in discussions (n = 26) regarding their work roles, continuing education and interactions with specialist nurse services when providing care for older people living with chronic illnesses. This nursing workforce is characterised by ageing, relative isolation, reduced confidence and few opportunities for induction of new graduates. Registered nurses reported their struggle to deliver the appropriate quality of care to residents as acuity increases, general practitioner availability decreases and the opportunities for increasing their knowledge and competence remain limited. The provision of nursing services in residential care for older people is an area of growing concern to many Western countries. Nurse practitioners offer opportunities to improve the quality of residential care.
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    The Cannabis Use Problems Identification Test (CUPIT): Development, reliability, concurrent and predictive validity among adolescents and adults
    (John Wiley & Sons, 2010) Bashford J; Flett R; Copeland J
    AIMS: To describe the empirical construction and initial validation of the Cannabis Use Problems Identification Test (CUPIT), a brief self-report screening instrument for detection of currently and potentially problematic cannabis use.DESIGN: In a three-phase prospective design an item pool of candidate questions was generated from a literature review and extensive expert consultation. The CUPIT internal structure, cross-sectional and longitudinal psychometric properties were then systematically tested among heterogeneous past-year users.PARTICIPANTS: Volunteer participants were 212 high-risk adolescents (n = 138) and adults (n = 74) aged 13-61 years from multiple community settings.MEASUREMENTS: The comprehensive assessment battery included several established measures of cannabis-related pathology for CUPIT validation, with DSM-IV/ICD-10 diagnoses of cannabis use disorders as criterion standard.FINDINGS: Sixteen items loading highly on two subscales derived from principal components analysis exhibited good to excellent test-retest (0.89-0.99) and internal consistency reliability (0.92, 0.83), and highly significant ability to discriminate diagnostic subgroups along the severity continuum (non-problematic, risky, problematic use). Twelve months later, baseline CUPIT scores demonstrated highly significant longitudinal predictive utility for respondents' follow-up diagnostic group membership. Receiver operating characteristic (ROC) analysis identified a CUPIT score of 12 to be the optimal cut-point for maximizing sensitivity for both currently diagnosable cannabis use disorder and those at risk of meeting diagnostic criteria in the following 12 months.CONCLUSIONS: The CUPIT is a brief cannabis screener that is reliable, valid and acceptable for use across diverse community settings and consumers of all ages. The CUPIT has clear potential to assist with achievement of public health goals to reduce cannabis-related harms in the community.
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    THE SHORT-TERM EFFECT OF IRRADIANCE ON THE PHOTOSYNTHETIC PROPERTIES OF ANTARCTIC FAST-ICE MICROALGAL COMMUNITIES(1).
    (WILEY-BLACKWELL PUBLISHING, INC, 2009-12) Ryan KG; Cowie ROM; Liggins E; McNaughtan D; Martin A; Davy SK
    Although sea-ice represents a harsh physicochemical environment with steep gradients in temperature, light, and salinity, diverse microbial communities are present within the ice matrix. We describe here the photosynthetic responses of sea-ice microalgae to varying irradiances. Rapid light curves (RLCs) were generated using pulse amplitude fluorometry and used to derive photosynthetic yield (ΦPSII ), photosynthetic efficiency (α), and the irradiance (Ek ) at which relative electron transport rate (rETR) saturates. Surface brine algae from near the surface and bottom-ice algae were exposed to a range of irradiances from 7 to 262 μmol photons · m(-2)  · s(-1) . In surface brine algae, ΦPSII and α remained constant at all irradiances, and rETRmax peaked at 151 μmol photons · m(-2)  · s(-1) , indicating these algae are well acclimated to the irradiances to which they are normally exposed. In contrast, ΦPSII , α, and rETRmax in bottom-ice algae reduced when exposed to irradiances >26 μmol photons · m(-2)  · s(-1) , indicating a high degree of shade acclimation. In addition, the previous light history had no significant effect on the photosynthetic capacity of bottom-ice algae whether cells were gradually exposed to target irradiances over a 12 h period or were exposed immediately (light shocked). These findings indicate that bottom-ice algae are photoinhibited in a dose-dependent manner, while surface brine algae tolerate higher irradiances. Our study shows that sea-ice algae are able to adjust to changes in irradiance rapidly, and this ability to acclimate may facilitate survival and subsequent long-term acclimation to the postmelt light regime of the Southern Ocean.
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    Could mild hypoxia impair pilot decision making in emergencies?
    (IOS PRESS, 2012) Legg S; Hill S; Mundel T; Gilbey A; Schlader Z; Raman A
    The decreased pressure in the cabin of a pressurised aircraft (typically equivalent to ~8000 ft) reduces the oxygen level so that the blood oxygen saturation of all occupants falls from >97% (normoxia) at sea-level to below 92% (mild hypoxia). Although exposure to mild hypoxia does not affect well-learned cognitive and motor performance of aircrew, it has been proposed that it can affect the performance of some complex cognitive performance tasks involving multiple demands typical of emergency tasks that may have to be performed by pilots. In order to simulate some of these complex cognitive demands, 25 student volunteers participated in an experiment which assessed performance of complex logical reasoning and and multiple memory tasks before and after 2 hours of exposure to normoxia and mild hypoxia. Performance for the more difficult components of the complex reasoning task, especially involving conflict decisions, were marginally significantly degraded by mild hypoxia. Since the effects were only marginally significant future studies should investigate the effects of mild hypoxia on more subtle complex decision-making tasks.
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    Filoviruses in bats: current knowledge and future directions.
    (MDPI AG, 17/04/2014) Olival KJ; Hayman DTS
    Filoviruses, including Ebolavirus and Marburgvirus, pose significant threats to public health and species conservation by causing hemorrhagic fever outbreaks with high mortality rates. Since the first outbreak in 1967, their origins, natural history, and ecology remained elusive until recent studies linked them through molecular, serological, and virological studies to bats. We review the ecology, epidemiology, and natural history of these systems, drawing on examples from other bat-borne zoonoses, and highlight key areas for future research. We compare and contrast results from ecological and virological studies of bats and filoviruses with those of other systems. We also highlight how advanced methods, such as more recent serological assays, can be interlinked with flexible statistical methods and experimental studies to inform the field studies necessary to understand filovirus persistence in wildlife populations and cross-species transmission leading to outbreaks. We highlight the need for a more unified, global surveillance strategy for filoviruses in wildlife, and advocate for more integrated, multi-disciplinary approaches to understand dynamics in bat populations to ultimately mitigate or prevent potentially devastating disease outbreaks.
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    Carbohydrate composition, viscosity, solubility, and sensory acceptance of sweetpotato- and maise-based complementary foods
    (Food and Nutrition Research, 2013) Amagloh FK; Mutukumira AN; Brough L; Weber JL; Hardacre A; Coad J
    Background: Cereal-based complementary foods from non-malted ingredients form a relatively high viscous porridge. Therefore, excessive dilution, usually with water, is required to reduce the viscosity to be appropriate for infant feeding. The dilution invariably leads to energy and nutrient thinning, that is, the reduction of energy and nutrient densities. Carbohydrate is the major constituent of food that significantly influences viscosity when heated in water. Objectives: To compare the sweetpotato-based complementary foods (extrusion-cooked ComFa, roller-dried ComFa, and oven-toasted ComFa) and enriched Weanimix (maize-based formulation) regarding their 1) carbohydrate composition, 2) viscosity and water solubility index (WSI), and 3) sensory acceptance evaluated by sub-Sahara African women as model caregivers. Methods: The level of simple sugars/carbohydrates was analysed by spectrophotometry, total dietary fibre by enzymatic-gravimetric method, and total carbohydrate and starch levels estimated by calculation. A Rapid ViscoTM Analyser was used to measure viscosity. WSI was determined gravimetrically. A consumer sensory evaluation was used to evaluate the product acceptance of the roller-dried ComFa, oven-toasted ComFa, and enriched Weanimix. Results: The sweetpotato-based complementary foods were, on average, significantly higher in maltose, sucrose, free glucose and fructose, and total dietary fibre, but they were markedly lower in starch content compared with the levels in the enriched Weanimix. Consequently, the sweetpotato-based complementary foods had relatively low apparent viscosity, and high WSI, than that of enriched Weanimix. The scores of sensory liking given by the caregivers were highest for the roller-dried ComFa, followed by the oven-toasted ComFa, and, finally, the enriched Weanimix. Conclusion: The sweetpotato-based formulations have significant advantages as complementary food due to the high level of endogenous sugars and low starch content that reduce the viscosity, increase the solubility, impart desirable sensory characteristics, and potentially avoid excessive energy and nutrient thinning.
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    Sublethal exposure to commercial formulations of the herbicides dicamba, 2,4-dichlorophenoxyacetic acid, and glyphosate cause changes in antibiotic susceptibility in Escherichia coli and Salmonella enterica serovar Typhimurium.
    (AMER SOC MICROBIOLOGY, 24/03/2015) Kurenbach B; Marjoshi D; Amábile-Cuevas CF; Ferguson GC; Godsoe W; Gibson P; Heinemann JA
    UNLABELLED: Biocides, such as herbicides, are routinely tested for toxicity but not for sublethal effects on microbes. Many biocides are known to induce an adaptive multiple-antibiotic resistance phenotype. This can be due to either an increase in the expression of efflux pumps, a reduced synthesis of outer membrane porins, or both. Exposures of Escherichia coli and Salmonella enterica serovar Typhimurium to commercial formulations of three herbicides-dicamba (Kamba), 2,4-dichlorophenoxyacetic acid (2,4-D), and glyphosate (Roundup)-were found to induce a changed response to antibiotics. Killing curves in the presence and absence of sublethal herbicide concentrations showed that the directions and the magnitudes of responses varied by herbicide, antibiotic, and species. When induced, MICs of antibiotics of five different classes changed up to 6-fold. In some cases the MIC increased, and in others it decreased. Herbicide concentrations needed to invoke the maximal response were above current food maximum residue levels but within application levels for all herbicides. Compounds that could cause induction had additive effects in combination. The role of soxS, an inducer of the AcrAB efflux pump, was tested in β-galactosidase assays with soxS-lacZ fusion strains of E. coli. Dicamba was a moderate inducer of the sox regulon. Growth assays with Phe-Arg β-naphtylamide (PAβN), an efflux pump inhibitor, confirmed a significant role of efflux in the increased tolerance of E. coli to chloramphenicol in the presence of dicamba and to kanamycin in the presence of glyphosate. Pathways of exposure with relevance to the health of humans, domestic animals, and critical insects are discussed. IMPORTANCE: Increasingly common chemicals used in agriculture, domestic gardens, and public places can induce a multiple-antibiotic resistance phenotype in potential pathogens. The effect occurs upon simultaneous exposure to antibiotics and is faster than the lethal effect of antibiotics. The magnitude of the induced response may undermine antibiotic therapy and substantially increase the probability of spontaneous mutation to higher levels of resistance. The combination of high use of both herbicides and antibiotics in proximity to farm animals and important insects, such as honeybees, might also compromise their therapeutic effects and drive greater use of antibiotics. To address the crisis of antibiotic resistance requires broadening our view of environmental contributors to the evolution of resistance.