329 research outputs found

    The effect of ultraviolet C radiation on stored-product pests

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    The potential of using ultraviolet C (UVC) radiation as an alternative treatment and hygiene measure in storage premises was investigated in the laboratory. The effect of UVC on development and progeny production was assessed for pest species of the storage beetles Oryzaephilus surinamensis and Tribolium castaneum, and the mites, Acarus siro and Tyrophagus putrescentiae. Photo-reactivation and the effect of indirect exposure were also investigated, as was the effect on spore germination of a mycotoxin-producing fungus Penicillium verrucosum. The ED95 values for O. surinamensis, T. castaneum, T. putrescentiae and A. siro were 96,549, 59,069, 22,014 and 3,802 μJ cm-2 respectively, when incubated in lighted conditions. There was an indication of a photo-reactivation effect with T. putrescentiae. Limited penetrative ability through substrates was observed at the doses assessed. Complete prevention of spore germination and complete spore destruction of P. verrucosum was achieved at 20,000 and 25,000 μJ cm-2 respectively. There was no significant difference in the numbers of O. surinamensis, T. castaneum and T. putrescentiae progeny produced by untreated females and females treated with a sub-lethal dose of UVC. However, there was a large degree of variation in the number of progeny produced by individual females. There was a significant reduction in the numbers of A. siro progeny produced by UVC treated females compared to untreated females; however, the majority of females died during the incubation period before any eggs had been laid. Practical applications of UVC within a storage environment may lie in the treatment of structural and equipment surfaces, such as conveyor systems. However, cleaning prior to treatment is an important consideration as UVC has limited penetrative ability. Keywords: Ultraviolet C radiation; Storage beetle, Mite and fungal pests; Structural treatment; Hygienemeasure

    An integrated model of staff education and service support to strengthen the efficacy of technology-based crisis services

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    Paper presented at the National Suicide Prevention Conference, 24-27 July 2016, Canberra, Australia. Within Australia, non-clinical telephone and online crisis support services provide readily accessible support without the requirement of referral. Research shows that up to one third of callers to crisis lines and half of all visitors to crisis chat services may be suicidal at the time of contact. Research also shows that contact with these services reduces caller suicidality and facilitates engagement with necessary intervention. The number of contacts to crisis support services in Australia is increasing. An increase in contacts to technology-based crisis services highlights the need to identify the impact of the role on crisis support staff wellbeing, determinants of staff wellbeing in the technology-based crisis support context and the extent to which the wellbeing of crisis support staff impacts their performance and client outcomes. This paper presents the evidence for an integrated model of staff education and service support that is grounded in medical education theory and can be used to underpin future research and staff (1) recruitment, (2) training, (3) skill assessment, (4) personal development and individual processes to maintain wellbeing (e.g. self-care), (5) supervisor training and staff support strategies (e.g. learning, teaching and facilitating a reflective practice model for supervision and staff professional development), and (6) service support strategies (e.g. organisational personal and professional support strategies that compliment staff supervision)

    Help-negation among telephone crisis support workers: Impact on personal wellbeing and worker performance

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    Paper presented at the National Suicide Prevention Conference, 24-26 July 2013, Melbourne, Australia. Telephone counsellors (TCs) provide front line mental health support to callers in crisis. TCs often support callers with suicidal thoughts, depression and anxiety, and the caller\u27s experience of the call will influence whether they will seek help from a helpline in the future. Despite their important role, little information on TCs\u27 mental health and help-seeking behaviours exists - a structured literature search returned 2 papers. This paper presents the results of a study that answered three research questions: 1. Do telephone counsellors experience symptoms of suicidal ideation, depression and anxiety? 2. Do telephone counsellors intend to seek help for these symptoms? 3. Do service provision intentions vary for telephone counsellors experiencing different levels of symptoms? A representative sample of 124 Lifeline Telephone Crisis Supporters (TCSs) from across Australia took part in the study. Results suggest that help-negation (reluctance to seek help as distress levels increase) occurs among TCSs who are exposed to suicidal, depressed and anxious callers, and impacts both personal wellbeing and TCSs intention to use recommended skills with callers. The impact of exposure to callers in crisis is an occupational hazard for all telephone counsellors in the sector. Implications for TC training, preparation, supervision, and support are discussed

    Seamounts as refugia from ocean acidification for cold-water stony corals

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    Cold-water stony corals create habitat for a diverse range of deep-water species but are thought to be threatened by ocean acidification due to oceanic uptake of anthropogenic CO2. Knowledge of the severity of this threat is hampered by our limited understanding of the distribution and habitat requirements of these corals. Here we estimate the global acidification threat to these organisms using a global database of cold-water stony coral records and a species distribution modelling approach. We parameterised the models using present-day environmental data, and then replaced these data with future projections of ocean chemistry from the year 2099. We found suitable coral habitat to be very heterogeneously distributed, being concentrated in the northern North Atlantic and around New Zealand. Projected changes in ocean chemistry induced a pronounced reduction in habitat suitability in the North Atlantic, and a low-to-moderate impact elsewhere under both the IPCC IS92a and S650 scenarios. Seamount summits are impacted by these changes, but consistently provide more suitable habitat than the surrounding seafloor, with around 98% of seamount summits having higher suitability in both future scenarios; this is because they lie in shallower waters with a higher aragonite saturation state. These results suggest that anthropogenic-induced changes in ocean chemistry are likely to severely impact cold-water stony coral habitat in the deep-sea of the North Atlantic, and that impacts will be less severe elsewhere. We predict that coral communities on the summits and upper slopes of seamounts will be less susceptible to ocean acidification during this century than those on the surrounding seafloor, and thus that seamounts may serve as temporary refugia. © 2010 Blackwell Verlag GmbH

    Predicting global habitat suitability for stony corals on seamounts

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    Aim Globally, species distribution patterns in the deep sea are poorly resolved, with spatial coverage being sparse for most taxa and true absence data missing. Increasing human impacts on deep-sea ecosystems mean that reaching a better understanding of such patterns is becoming more urgent. Cold-water stony corals (Order Scleractinia) form structurally complex habitats (dense thickets or reefs) that can support a diversity of other associated fauna. Despite their widely accepted ecological importance, records of scleractinian corals on seamounts are patchy and simply not available for most of the global ocean. The objective of this paper is to model the global distribution of suitable habitat for stony corals on seamounts. Location Seamounts worldwide. Methods We compiled a database containing all accessible records of scleractinian corals on seamounts. Two modelling approaches developed for presence-only data were used to predict global habitat suitability for seamount scleractinians: maximum entropy modelling (Maxent) and environmental niche factor analysis (ENFA). We generated habitat-suitability maps and used a cross-validation process with a threshold-independent metric to evaluate the performance of the models. Results Both models performed well in cross-validation, although the Maxent method consistently outperformed ENFA. Highly suitable habitat for seamount stony corals was predicted to occur at most modelled depths in the North Atlantic, and in a circumglobal strip in the Southern Hemisphere between 20° and 50° S and shallower than around 1500 m. Seamount summits in most other regions appeared much less likely to provide suitable habitat, except for small near-surface patches. The patterns of habitat suitability largely reflect current biogeographical knowledge. Environmental variables positively associated with high predicted habitat suitability included the aragonite saturation state, and oxygen saturation and concentration. By contrast, low levels of dissolved inorganic carbon, nitrate, phosphate and silicate were associated with high predicted suitability. High correlation among variables made assessing individual drivers difficult. Main conclusions Our models predict environmental conditions likely to play a role in determining large-scale scleractinian coral distributions on seamounts, and provide a baseline scenario on a global scale. These results present a first-order hypothesis that can be tested by further sampling. Given the high vulnerability of cold-water corals to human impacts, such predictions are crucial tools in developing worldwide conservation and management strategies for seamount ecosystems. © 2009 Blackwell Publishing Ltd

    Tuna Longline Fishing around West and Central Pacific Seamounts

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    BACKGROUND: Seamounts have been identified as aggregating locations for pelagic biodiversity including tuna; however the topography and prevailing oceanography differ between seamounts and not all are important for tuna. Although a relatively common feature in oceanic ecosystems, little information is available that identifies those that are biologically important. Improved knowledge offers opportunities for unique management of these areas, which may advance the sustainable management of oceanic resources. In this study, we evaluate the existence of an association between seamounts and tuna longline fisheries at the ocean basin scale, identify significant seamounts for tuna in the western and central Pacific Ocean, and quantify the seamount contribution to the tuna longline catch. METHODOLOGY/PRINCIPAL FINDINGS: We use data collected for the Western and Central Pacific Ocean for bigeye, yellowfin, and albacore tuna at the ocean basin scale. GLMs were applied to a coupled dataset of longline fisheries catch and effort, and seamount location information. The analyses show that seamounts may be associated with an annual longline combined catch of 35 thousand tonnes, with higher catch apparent for yellowfin, bigeye, and albacore tuna on 17%, 14%, and 14% of seamounts respectively. In contrast 14%, 18%, and 20% of seamounts had significantly lower catches for yellowfin, bigeye and albacore tuna respectively. Studying catch data in relation to seamount positions presents several challenges such as bias in location of seamounts, or lack of spatial resolution of fisheries data. Whilst we recognize these limitations the criteria used for detecting significant seamounts were conservative and the error in identification is likely to be low albeit unknown. CONCLUSIONS/SIGNIFICANCE: Seamounts throughout the study area were found to either enhance or reduce tuna catch. This indicates that management of seamounts is important Pacific-wide, but management approaches must take account of local conditions. Management of tuna and biodiversity resources in the region would benefit from considering such effects

    Sigma-phase in Fe-Cr and Fe-V alloy systems and its physical properties

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    A review is presented on physical properties of the sigma-phase in Fe-Cr and Fe-V alloy systems as revealed both with experimental -- mostly with the Mossbauer spectroscopy -- and theoretical methods. In particular, the following questions relevant to the issue have been addressed: identification of sigma and determination of its structural properties, kinetics of alpha-to-sigma and sigma-to-alpha phase transformations, Debye temperature and Fe-partial phonon density of states, Curie temperature and magnetization, hyperfine fields, isomer shifts and electric field gradients.Comment: 26 pages, 23 figures and 83 reference

    Integrating Multiple Data Types to Connect Ecological Theory and Data Among Levels

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    Ecological theories often encompass multiple levels of biological organization, such as genes, individuals, populations, and communities. Despite substantial progress toward ecological theory spanning multiple levels, ecological data rarely are connected in this way. This is unfortunate because different types of ecological data often emerge from the same underlying processes and, therefore, are naturally connected among levels. Here, we describe an approach to integrate data collected at multiple levels (e.g., individuals, populations) in a single statistical analysis. The resulting integrated models make full use of existing data and might strengthen links between statistical ecology and ecological models and theories that span multiple levels of organization. Integrated models are increasingly feasible due to recent advances in computational statistics, which allow fast calculations of multiple likelihoods that depend on complex mechanistic models. We discuss recently developed integrated models and outline a simple application using data on freshwater fishes in south-eastern Australia. Available data on freshwater fishes include population survey data, mark-recapture data, and individual growth trajectories. We use these data to estimate age-specific survival and reproduction from size-structured data, accounting for imperfect detection of individuals. Given that such parameter estimates would be infeasible without an integrated model, we argue that integrated models will strengthen ecological theory by connecting theoretical and mathematical models directly to empirical data. Although integrated models remain conceptually and computationally challenging, integrating ecological data among levels is likely to be an important step toward unifying ecology among levels

    Persistence of TEL-AML1 fusion gene as minimal residual disease has no additive prognostic value in CD 10 positive B-acute lymphoblastic leukemia: a FISH study

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    <p>Abstract</p> <p>Objectives </p> <p>We have analyzed t(12;21)(p13:q22) in an attempt to evaluate the frequency and prognostic significance of <it>TEL-AML1 </it>fusion gene in patients with childhood CD 10 positive B-ALL by fluorescence in situ hybridization (FISH). Also, we have monitored the prognostic value of this gene as a minimal residual disease (MRD).</p> <p>Methods</p> <p>All bone marrow samples of eighty patients diagnosed as CD 10 positive B-ALL in South Egypt Cancer Institute were evaluated by fluorescence in situ hybridization (FISH) for t(12;21) in newly diagnosed cases and after morphological complete remission as a minimal residual disease (MRD). We determined the prognostic significance of <it>TEL-AML1 </it>fusion represented by disease course and survival.</p> <p>Results</p> <p><it>TEL-AML1 </it>fusion gene was positive in (37.5%) in newly diagnosed patients. There was a significant correlation between <it>TEL-AML1 </it>fusion gene both at diagnosis (r = 0.5, P = 0.003) and as a MRD (r = 0.4, P = 0.01) with favorable course. Kaplan-Meier curve for the presence of <it>TEL-AML1 </it>fusion at the diagnosis was associated with a better probability of overall survival (OS); mean survival time was 47 ± 1 month, in contrast to 28 ± 5 month in its absence (P = 0.006). Also, the persistence at <it>TEL-AML1 </it>fusion as a MRD was not significantly associated with a better probability of OS; the mean survival time was 42 ± 2 months in the presence of MRD and it was 40 ± 1 months in its absence. So, persistence of <it>TEL-AML1 </it>fusion as a MRD had no additive prognostic value over its measurement at diagnosis in terms of predicting the probability of OS.</p> <p>Conclusion</p> <p>For most patients, the presence of <it>TEL-AML1 </it>fusion gene at diagnosis suggests a favorable prognosis. The present study suggests that persistence of <it>TEL-AML1 </it>fusion as MRD has no additive prognostic value.</p
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