A configural model of expert judgement as a preliminary epidemiological study of injury problems: An application to drowning
- Morgan, Damian, Ozanne-Smith, Joan
- Authors: Morgan, Damian , Ozanne-Smith, Joan
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 10 (2019), p.
- Full Text:
- Reviewed:
- Description: Robust epidemiological studies identifying determinants of negative health outcomes require significant research effort. Expert judgement is proposed as an efficient alternative or preliminary research design for risk factor identification associated with unintentional injury. This proposition was tested in a multi-factorial balanced experimental design using specialist judges (N = 18), lifeguards and surfers, to assess the risk contribution to drowning for swimming ability, surf bathing experience, and wave height. All factors provided unique contributions to drowning risk (p < .001). An interaction (p = .02) indicated that occasional surf bathers face a proportionally increased risk of drowning at increased wave heights relative to experienced surf bathers. Although findings were limited by strict criteria, and no gold standard comparison data were available, the study provides new evidence on causal risk factors for a drowning scenario. Countermeasures based on these factors are proposed. Further application of the method may assist in developing new interventions to reduce unintentional injury. © 2019 Morgan, Ozanne-Smith. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Authors: Morgan, Damian , Ozanne-Smith, Joan
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 10 (2019), p.
- Full Text:
- Reviewed:
- Description: Robust epidemiological studies identifying determinants of negative health outcomes require significant research effort. Expert judgement is proposed as an efficient alternative or preliminary research design for risk factor identification associated with unintentional injury. This proposition was tested in a multi-factorial balanced experimental design using specialist judges (N = 18), lifeguards and surfers, to assess the risk contribution to drowning for swimming ability, surf bathing experience, and wave height. All factors provided unique contributions to drowning risk (p < .001). An interaction (p = .02) indicated that occasional surf bathers face a proportionally increased risk of drowning at increased wave heights relative to experienced surf bathers. Although findings were limited by strict criteria, and no gold standard comparison data were available, the study provides new evidence on causal risk factors for a drowning scenario. Countermeasures based on these factors are proposed. Further application of the method may assist in developing new interventions to reduce unintentional injury. © 2019 Morgan, Ozanne-Smith. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Algorithm development for the non-destructive testing of structural damage
- Noori Hoshyar, Azadeh, Rashidi, Maria, Liyanapathirana, Ranjith, Samali, Bijan
- Authors: Noori Hoshyar, Azadeh , Rashidi, Maria , Liyanapathirana, Ranjith , Samali, Bijan
- Date: 2019
- Type: Text , Journal article
- Relation: Applied sciences Vol. 9, no. 14 (2019), p. 2810
- Full Text:
- Reviewed:
- Description: Monitoring of structures to identify types of damages that occur under loading is essential in practical applications of civil infrastructure. In this paper, we detect and visualize damage based on several non-destructive testing (NDT) methods. A machine learning (ML) approach based on the Support Vector Machine (SVM) method is developed to prevent misdirection of the event interpretation of what is happening in the material. The objective is to identify cracks in the early stages, to reduce the risk of failure in structures. Theoretical and experimental analyses are derived by computing the performance indicators on the smart aggregate (SA)-based sensor data for concrete and reinforced-concrete (RC) beams. Validity assessment of the proposed indices was addressed through a comparative analysis with traditional SVM. The developed ML algorithms are shown to recognize cracks with a higher accuracy than the traditional SVM. Additionally, we propose different algorithms for microwave- or millimeter-wave imaging of steel plates, composite materials, and metal plates, to identify and visualize cracks. The proposed algorithm for steel plates is based on the gradient magnitude in four directions of an image, and is followed by the edge detection technique. Three algorithms were proposed for each of composite materials and metal plates, and are based on 2D fast Fourier transform (FFT) and hybrid fuzzy c-mean techniques, respectively. The proposed algorithms were able to recognize and visualize the cracking incurred in the structure more efficiently than the traditional techniques. The reported results are expected to be beneficial for NDT-based applications, particularly in civil engineering.
- Authors: Noori Hoshyar, Azadeh , Rashidi, Maria , Liyanapathirana, Ranjith , Samali, Bijan
- Date: 2019
- Type: Text , Journal article
- Relation: Applied sciences Vol. 9, no. 14 (2019), p. 2810
- Full Text:
- Reviewed:
- Description: Monitoring of structures to identify types of damages that occur under loading is essential in practical applications of civil infrastructure. In this paper, we detect and visualize damage based on several non-destructive testing (NDT) methods. A machine learning (ML) approach based on the Support Vector Machine (SVM) method is developed to prevent misdirection of the event interpretation of what is happening in the material. The objective is to identify cracks in the early stages, to reduce the risk of failure in structures. Theoretical and experimental analyses are derived by computing the performance indicators on the smart aggregate (SA)-based sensor data for concrete and reinforced-concrete (RC) beams. Validity assessment of the proposed indices was addressed through a comparative analysis with traditional SVM. The developed ML algorithms are shown to recognize cracks with a higher accuracy than the traditional SVM. Additionally, we propose different algorithms for microwave- or millimeter-wave imaging of steel plates, composite materials, and metal plates, to identify and visualize cracks. The proposed algorithm for steel plates is based on the gradient magnitude in four directions of an image, and is followed by the edge detection technique. Three algorithms were proposed for each of composite materials and metal plates, and are based on 2D fast Fourier transform (FFT) and hybrid fuzzy c-mean techniques, respectively. The proposed algorithms were able to recognize and visualize the cracking incurred in the structure more efficiently than the traditional techniques. The reported results are expected to be beneficial for NDT-based applications, particularly in civil engineering.
Annual ryegrass (Lolium rigidum Gaud) competition altered wheat grain quality : A study under elevated atmospheric CO2 levels and drought conditions
- Fernando, Nimesha, Florentine, Singarayer, Naiker, Mani, Panozzo, Joe, Chauhan, Bhagirath
- Authors: Fernando, Nimesha , Florentine, Singarayer , Naiker, Mani , Panozzo, Joe , Chauhan, Bhagirath
- Date: 2019
- Type: Text , Journal article
- Relation: Food Chemistry Vol. 276, no. (2019), p. 285-290
- Full Text:
- Reviewed:
- Description: Annual ryegrass is one of the most serious, costly weeds of winter cropping systems in Australia. To determine whether its competition-mediated plant defence mechanisms effect on wheat grain quality, wheat (cv. Yitpi) and annual ryegrass were grown under two levels of CO2 (400 ppm; (a[CO2]) vs 700 ppm; (e[CO2]), two levels of water (well-watered vs drought) and two types of competition (wheat only; (W), and wheatxannual ryegrass; (W x R) with four replicates. The competitionx[CO2] interaction had a significant effect on wheat grain protein content, where it was increased in W x R under both e[CO2] (+ 17%) and a[CO2] (+ 21%). Grain yield, total grain reducing power and phenolic content were significantly affected by [CO2] x drought x competition. In a summary, annual ryegrass competition significantly altered the wheat grain quality under both [CO2] levels (depending on the soil water level), while also decreasing the grain yield.
- Authors: Fernando, Nimesha , Florentine, Singarayer , Naiker, Mani , Panozzo, Joe , Chauhan, Bhagirath
- Date: 2019
- Type: Text , Journal article
- Relation: Food Chemistry Vol. 276, no. (2019), p. 285-290
- Full Text:
- Reviewed:
- Description: Annual ryegrass is one of the most serious, costly weeds of winter cropping systems in Australia. To determine whether its competition-mediated plant defence mechanisms effect on wheat grain quality, wheat (cv. Yitpi) and annual ryegrass were grown under two levels of CO2 (400 ppm; (a[CO2]) vs 700 ppm; (e[CO2]), two levels of water (well-watered vs drought) and two types of competition (wheat only; (W), and wheatxannual ryegrass; (W x R) with four replicates. The competitionx[CO2] interaction had a significant effect on wheat grain protein content, where it was increased in W x R under both e[CO2] (+ 17%) and a[CO2] (+ 21%). Grain yield, total grain reducing power and phenolic content were significantly affected by [CO2] x drought x competition. In a summary, annual ryegrass competition significantly altered the wheat grain quality under both [CO2] levels (depending on the soil water level), while also decreasing the grain yield.
Autonomous adaptation to climate-driven change in marine biodiversity in a global marine hotspot
- Pecl, Gretta, Ogier, Emily, Jennings, Sarah, van Putten, Ingrid, Crawford, Christine, Fogarty, Hannah, Frusher, Stewart, Hobday, Alistair, Keane, John, Lee, Emma, MacLeod, Catriona, Mundy, Craig, Stuart-Smith, Jemima, Tracey, Sean
- Authors: Pecl, Gretta , Ogier, Emily , Jennings, Sarah , van Putten, Ingrid , Crawford, Christine , Fogarty, Hannah , Frusher, Stewart , Hobday, Alistair , Keane, John , Lee, Emma , MacLeod, Catriona , Mundy, Craig , Stuart-Smith, Jemima , Tracey, Sean
- Date: 2019
- Type: Text , Journal article
- Relation: Ambio Vol. 48, no. 12 (2019), p. 1498-1515
- Full Text:
- Reviewed:
- Description: While governments and natural resource managers grapple with how to respond to climatic changes, many marine-dependent individuals, organisations and user-groups in fast-changing regions of the world are already adjusting their behaviour to accommodate these. However, we have little information on the nature of these autonomous adaptations that are being initiated by resource user-groups. The east coast of Tasmania, Australia, is one of the world’s fastest warming marine regions with extensive climate-driven changes in biodiversity already observed. We present and compare examples of autonomous adaptations from marine users of the region to provide insights into factors that may have constrained or facilitated the available range of autonomous adaptation options and discuss potential interactions with governmental planned adaptations. We aim to support effective adaptation by identifying the suite of changes that marine users are making largely without government or management intervention, i.e. autonomous adaptations, to better understand these and their potential interactions with formal adaptation strategies. © 2019, Royal Swedish Academy of Sciences.
- Authors: Pecl, Gretta , Ogier, Emily , Jennings, Sarah , van Putten, Ingrid , Crawford, Christine , Fogarty, Hannah , Frusher, Stewart , Hobday, Alistair , Keane, John , Lee, Emma , MacLeod, Catriona , Mundy, Craig , Stuart-Smith, Jemima , Tracey, Sean
- Date: 2019
- Type: Text , Journal article
- Relation: Ambio Vol. 48, no. 12 (2019), p. 1498-1515
- Full Text:
- Reviewed:
- Description: While governments and natural resource managers grapple with how to respond to climatic changes, many marine-dependent individuals, organisations and user-groups in fast-changing regions of the world are already adjusting their behaviour to accommodate these. However, we have little information on the nature of these autonomous adaptations that are being initiated by resource user-groups. The east coast of Tasmania, Australia, is one of the world’s fastest warming marine regions with extensive climate-driven changes in biodiversity already observed. We present and compare examples of autonomous adaptations from marine users of the region to provide insights into factors that may have constrained or facilitated the available range of autonomous adaptation options and discuss potential interactions with governmental planned adaptations. We aim to support effective adaptation by identifying the suite of changes that marine users are making largely without government or management intervention, i.e. autonomous adaptations, to better understand these and their potential interactions with formal adaptation strategies. © 2019, Royal Swedish Academy of Sciences.
Belief in conspiracy theories : the predictive role of schizotypy, machiavellianism, and primary psychopathy
- Authors: March, Evita , Springer
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 12 (2019), p.
- Full Text:
- Reviewed:
- Description: A conspiracy theory refers to an alternative explanation of an event involving a conspirator plot organised by powerful people or organisations. Belief in conspiracy theories is related to negative societal outcomes such as poor medical decisions and a decrease in prosocial behaviour. Given these negative outcomes, researchers have explored predictors of belief in conspiracy theories in an attempt to understand and possibly manage these beliefs. In the current study, we explored the utility of personality in predicting belief in conspiracy theories. The aim of the current study was to explore the utility of the odd beliefs/magical thinking subtype of schizotypy, Machiavellianism, grandiose narcissism, vulnerable narcissism, primary psychopathy, and secondary psychopathy in predicting belief in conspiracy theories. Participants (N = 230; 44.7% male, 55.3% female) completed an anonymous, confidential online questionnaire which comprised demographics and measures of personality traits and belief in conspiracy theories. The total regression model indicated odd beliefs/magical thinking, trait Machiavellianism, and primary psychopathy were significant, positive predictors of belief in conspiracy theories. No other predictors reached significance. Results of the current study highlight individuals who might be more susceptible to believing conspiracy theories. Specifically, these results indicate that the individual more likely to believe in conspiracy theories may have unusual patterns of thinking and cognitions, be strategic and manipulative, and display interpersonal and affective deficits. © 2019 March, Springer. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Authors: March, Evita , Springer
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 12 (2019), p.
- Full Text:
- Reviewed:
- Description: A conspiracy theory refers to an alternative explanation of an event involving a conspirator plot organised by powerful people or organisations. Belief in conspiracy theories is related to negative societal outcomes such as poor medical decisions and a decrease in prosocial behaviour. Given these negative outcomes, researchers have explored predictors of belief in conspiracy theories in an attempt to understand and possibly manage these beliefs. In the current study, we explored the utility of personality in predicting belief in conspiracy theories. The aim of the current study was to explore the utility of the odd beliefs/magical thinking subtype of schizotypy, Machiavellianism, grandiose narcissism, vulnerable narcissism, primary psychopathy, and secondary psychopathy in predicting belief in conspiracy theories. Participants (N = 230; 44.7% male, 55.3% female) completed an anonymous, confidential online questionnaire which comprised demographics and measures of personality traits and belief in conspiracy theories. The total regression model indicated odd beliefs/magical thinking, trait Machiavellianism, and primary psychopathy were significant, positive predictors of belief in conspiracy theories. No other predictors reached significance. Results of the current study highlight individuals who might be more susceptible to believing conspiracy theories. Specifically, these results indicate that the individual more likely to believe in conspiracy theories may have unusual patterns of thinking and cognitions, be strategic and manipulative, and display interpersonal and affective deficits. © 2019 March, Springer. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
DNA barcoding and integrative taxonomy of the heterolepisma sclerophylla species complex (Zygentoma: Lepismatidae: Heterolepismatinae) and the description of two new species
- Smith, Graeme, Mitchell, Andrew, Lee, Timothy, Espinasa, Luis
- Authors: Smith, Graeme , Mitchell, Andrew , Lee, Timothy , Espinasa, Luis
- Date: 2019
- Type: Text , Journal article
- Relation: Records of the Australian Museum Vol. 71, no. 1 (2019), p. 1-32
- Full Text:
- Reviewed:
- Description: We present one of the first studies of DNA barcodes (COI sequences) in the basal insect order Zygentoma, and compare the data with nuclear (28S) and mitochondrial (16S) rDNA sequences and morphology for an integrative taxonomic study of the Heterolepisma sclerophylla Smith species group. DNA sequence analyses identified deep divisions between Queensland and New South Wales populations, and among populations in each state. Detailed morphological and morphometric evaluation of the specimens failed, in most cases, to identify unambiguous morphological characters of diagnostic value for each population, possibly due to the interaction of morphological conservatism with high levels of variability resulting from their continued moulting after reaching sexual maturity. Several strong consistent characters were identified to support the description of a southern Queensland population as a new species (Heterolepisma cooloola sp. nov.). The combined molecular and morphological data support the view that the presence of lanceolate scales and the absence of macrochaetae from the anterior margin of the frons are more significant to phylogeny than the arrangement of styli and the shape of the thoracic sternites in Heterolepisma. Specimens from Glen Davis, NSW, while indistinguishable from H. sclerophylla in all other characters examined, were found to possess one fewer pair of abdominal styli in both sexes and are also described as a new species (Heterolepisma coorongooba sp. nov.). Five lineages are recognized within the remaining NSW material but as reliable (non-overlapping) morphological and morphometric differences could not be identified, they are not described here as new species. Heterolepisma sclerophylla sensu stricto is considered to be a complex of morphologically ill-defined species or perhaps subspecies.
- Authors: Smith, Graeme , Mitchell, Andrew , Lee, Timothy , Espinasa, Luis
- Date: 2019
- Type: Text , Journal article
- Relation: Records of the Australian Museum Vol. 71, no. 1 (2019), p. 1-32
- Full Text:
- Reviewed:
- Description: We present one of the first studies of DNA barcodes (COI sequences) in the basal insect order Zygentoma, and compare the data with nuclear (28S) and mitochondrial (16S) rDNA sequences and morphology for an integrative taxonomic study of the Heterolepisma sclerophylla Smith species group. DNA sequence analyses identified deep divisions between Queensland and New South Wales populations, and among populations in each state. Detailed morphological and morphometric evaluation of the specimens failed, in most cases, to identify unambiguous morphological characters of diagnostic value for each population, possibly due to the interaction of morphological conservatism with high levels of variability resulting from their continued moulting after reaching sexual maturity. Several strong consistent characters were identified to support the description of a southern Queensland population as a new species (Heterolepisma cooloola sp. nov.). The combined molecular and morphological data support the view that the presence of lanceolate scales and the absence of macrochaetae from the anterior margin of the frons are more significant to phylogeny than the arrangement of styli and the shape of the thoracic sternites in Heterolepisma. Specimens from Glen Davis, NSW, while indistinguishable from H. sclerophylla in all other characters examined, were found to possess one fewer pair of abdominal styli in both sexes and are also described as a new species (Heterolepisma coorongooba sp. nov.). Five lineages are recognized within the remaining NSW material but as reliable (non-overlapping) morphological and morphometric differences could not be identified, they are not described here as new species. Heterolepisma sclerophylla sensu stricto is considered to be a complex of morphologically ill-defined species or perhaps subspecies.
How practitioners integrate decision triggers with existing metrics in conservation monitoring
- Foster, Claire, O'Loughlin, Luke, Sato, Chloe, Westgate, Martin, Barton, Philip
- Authors: Foster, Claire , O'Loughlin, Luke , Sato, Chloe , Westgate, Martin , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Journal of Environmental Management Vol. 230, no. (2019), p. 94-101
- Full Text:
- Reviewed:
- Description: Decision triggers are defined thresholds in the status of monitored variables that indicate when to undertake management, and avoid undesirable ecosystem change. Decision triggers are frequently recommended to conservation practitioners as a tool to facilitate evidence-based management practices, but there has been limited attention paid to how practitioners are integrating decision triggers into existing monitoring programs. We sought to understand whether conservation practitioners’ use of decision triggers was influenced by the type of variables in their monitoring programs. We investigated this question using a practitioner-focused workshop involving a structured discussion and review of eight monitoring programs. Among our case studies, direct measures of biodiversity (e.g. native species) were more commonly monitored, but less likely to be linked to decision triggers (10% with triggers) than measures being used as surrogates (54% with triggers) for program objectives. This was because decision triggers were associated with management of threatening processes, which were often monitored as a surrogate for a biodiversity asset of interest. By contrast, direct measures of biodiversity were more commonly associated with informal decision processes that led to activities such as management reviews or external consultation. Workshop participants were in favor of including more formalized decision triggers in their programs, but were limited by incomplete ecological knowledge, lack of appropriately skilled staff, funding constraints, and/or uncertainty regarding intervention effectiveness. We recommend that practitioners consider including decision triggers for discussion activities (such as external consultation) in their programs as more than just early warning points for future interventions, particularly for direct measures. Decision triggers for discussions should be recognized as a critical feature of monitoring programs where information and operational limitations inhibit the use of decision triggers for interventions. © 2018 Elsevier Ltd. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
- Authors: Foster, Claire , O'Loughlin, Luke , Sato, Chloe , Westgate, Martin , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Journal of Environmental Management Vol. 230, no. (2019), p. 94-101
- Full Text:
- Reviewed:
- Description: Decision triggers are defined thresholds in the status of monitored variables that indicate when to undertake management, and avoid undesirable ecosystem change. Decision triggers are frequently recommended to conservation practitioners as a tool to facilitate evidence-based management practices, but there has been limited attention paid to how practitioners are integrating decision triggers into existing monitoring programs. We sought to understand whether conservation practitioners’ use of decision triggers was influenced by the type of variables in their monitoring programs. We investigated this question using a practitioner-focused workshop involving a structured discussion and review of eight monitoring programs. Among our case studies, direct measures of biodiversity (e.g. native species) were more commonly monitored, but less likely to be linked to decision triggers (10% with triggers) than measures being used as surrogates (54% with triggers) for program objectives. This was because decision triggers were associated with management of threatening processes, which were often monitored as a surrogate for a biodiversity asset of interest. By contrast, direct measures of biodiversity were more commonly associated with informal decision processes that led to activities such as management reviews or external consultation. Workshop participants were in favor of including more formalized decision triggers in their programs, but were limited by incomplete ecological knowledge, lack of appropriately skilled staff, funding constraints, and/or uncertainty regarding intervention effectiveness. We recommend that practitioners consider including decision triggers for discussion activities (such as external consultation) in their programs as more than just early warning points for future interventions, particularly for direct measures. Decision triggers for discussions should be recognized as a critical feature of monitoring programs where information and operational limitations inhibit the use of decision triggers for interventions. © 2018 Elsevier Ltd. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Philip Barton” is provided in this record**
Influence of soil moisture regimes on growth, photosynthetic capacity, leaf biochemistry and reproductive capabilities of the invasive agronomic weed; Lactuca serriola
- Chadha, Aakansha, Florentine, Singarayer, Chauhan, Bhagirath, Long, Benjamin, Jayasundera, Mithila
- Authors: Chadha, Aakansha , Florentine, Singarayer , Chauhan, Bhagirath , Long, Benjamin , Jayasundera, Mithila
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 6 (2019), p. 1-17
- Full Text:
- Reviewed:
- Description: Global temperatures are predicted to increase by 1.5–5.9C during this century, and this change is likely to impact average rainfall, with predictions that water deficit will perhaps be the most severe threat to sustainable agriculture. In this respect, invasive weeds, which have traits better adapted to drought stress than crops, add to concerns regarding crop sustainability. Lactuca serriola, an aggressive agronomic weed is thought to be a successful weed because of its ability to maintain high water use efficiency under drought conditions. In this study, experiments were conducted to examine the influence of different soil moisture regimes (100%, 75%, 50% and 25% water holding capacity (WHC)) on growth, photosynthetic capacity, leaf biochemistry and reproduction of this species. Soil moisture significantly affected plant’s height, stem diameter, number of leaves and biomass. The highest plant height (115.14 cm ± 11.64), shoot diameter (9.4 mm ± 0.18), leaf area (1206.5 mm2 ± 73.29), plant fresh weight (83.1 ± 3.98) and dry weight (22.38 ± 1.24) were recorded at 75% soil moisture content. A fundamental adaptation to drought was observed as plants in the 25% WHC treatment had the highest root: shoot ratio. Soluble sugars and total phenolic content were highest in the 25% WHC treatment and significantly different to 100% WHC which was a response to soil moisture stress to ameliorate the damaging effects of reactive oxygen species produced under stress conditions. Results also indicate that L. serriola can survive and produce seeds under water stress as more than 6000 seeds were produced per plant in all WHC treatments. In this study, there was no significant difference in the seed weight, number of seeds produced and their germination ability. This can have a huge impact on agricultural systems as the species can survive both under low and high soil moisture conditions. We therefore suggest that the demonstrated ability of L. serriola to complete its life cycle and produce biomass and seeds under water stressed conditions leads to the introduction of strategies that minimize weed survival while maximizing irrigation efficiency for the crop. A clear understanding of the ecological and biological characteristics of this weed will help land managers take appropriate control measures to mitigate the effect of this species on economic crop productivity.
- Authors: Chadha, Aakansha , Florentine, Singarayer , Chauhan, Bhagirath , Long, Benjamin , Jayasundera, Mithila
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 6 (2019), p. 1-17
- Full Text:
- Reviewed:
- Description: Global temperatures are predicted to increase by 1.5–5.9C during this century, and this change is likely to impact average rainfall, with predictions that water deficit will perhaps be the most severe threat to sustainable agriculture. In this respect, invasive weeds, which have traits better adapted to drought stress than crops, add to concerns regarding crop sustainability. Lactuca serriola, an aggressive agronomic weed is thought to be a successful weed because of its ability to maintain high water use efficiency under drought conditions. In this study, experiments were conducted to examine the influence of different soil moisture regimes (100%, 75%, 50% and 25% water holding capacity (WHC)) on growth, photosynthetic capacity, leaf biochemistry and reproduction of this species. Soil moisture significantly affected plant’s height, stem diameter, number of leaves and biomass. The highest plant height (115.14 cm ± 11.64), shoot diameter (9.4 mm ± 0.18), leaf area (1206.5 mm2 ± 73.29), plant fresh weight (83.1 ± 3.98) and dry weight (22.38 ± 1.24) were recorded at 75% soil moisture content. A fundamental adaptation to drought was observed as plants in the 25% WHC treatment had the highest root: shoot ratio. Soluble sugars and total phenolic content were highest in the 25% WHC treatment and significantly different to 100% WHC which was a response to soil moisture stress to ameliorate the damaging effects of reactive oxygen species produced under stress conditions. Results also indicate that L. serriola can survive and produce seeds under water stress as more than 6000 seeds were produced per plant in all WHC treatments. In this study, there was no significant difference in the seed weight, number of seeds produced and their germination ability. This can have a huge impact on agricultural systems as the species can survive both under low and high soil moisture conditions. We therefore suggest that the demonstrated ability of L. serriola to complete its life cycle and produce biomass and seeds under water stressed conditions leads to the introduction of strategies that minimize weed survival while maximizing irrigation efficiency for the crop. A clear understanding of the ecological and biological characteristics of this weed will help land managers take appropriate control measures to mitigate the effect of this species on economic crop productivity.
Leaders' creation of shared identity impacts group members' effort and performance : evidence from an exercise task
- Stevens, Mark, Rees, Tim, Steffens, Niklas, Haslam, S., Coffee, Pete, Polman, Remco
- Authors: Stevens, Mark , Rees, Tim , Steffens, Niklas , Haslam, S. , Coffee, Pete , Polman, Remco
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 7 (2019), p.
- Full Text:
- Reviewed:
- Description: There is growing evidence that leaders' effectiveness derives in part from their creation of a sense of identity that is shared by members of a group they are attempting to lead (i.e., their identity entrepreneurship). Little is known, however, about the impact of identity entrepreneurship in sport and exercise settings, particularly in relation to its effect on group members' effort and performance. Using a pre-post between subjects experimental design, we examined the effect of leaders' identity entrepreneurship on group members' effort and performance during 5km cycling time trials. Following a baseline session (in which time trials were completed individually), participants (N = 72) were randomly allocated to either a high or low identity entrepreneurship condition, and further randomly divided into groups of five (including a leader who was a confederate). In the subsequent test sessions (which participants attended with their fellow group members), leaders displayed either high or low identity entrepreneurship behaviors. Results indicated that, compared to participants in the low identity entrepreneurship condition, those in the high identity entrepreneurship condition maintained greater effort (maximum heart rate), and demonstrated improved (rather than poorer) performance (average power output in the first 60 seconds of time trials). Examination of pacing showed that the largest increases in participants' average power output occurred in the early stages of their second time trials for those in the high identity entrepreneurship condition only. Results provide causal evidence that leaders who create a shared sense of identity among team members are able to inspire greater participant effort and performance. © 2019 Stevens et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Authors: Stevens, Mark , Rees, Tim , Steffens, Niklas , Haslam, S. , Coffee, Pete , Polman, Remco
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 7 (2019), p.
- Full Text:
- Reviewed:
- Description: There is growing evidence that leaders' effectiveness derives in part from their creation of a sense of identity that is shared by members of a group they are attempting to lead (i.e., their identity entrepreneurship). Little is known, however, about the impact of identity entrepreneurship in sport and exercise settings, particularly in relation to its effect on group members' effort and performance. Using a pre-post between subjects experimental design, we examined the effect of leaders' identity entrepreneurship on group members' effort and performance during 5km cycling time trials. Following a baseline session (in which time trials were completed individually), participants (N = 72) were randomly allocated to either a high or low identity entrepreneurship condition, and further randomly divided into groups of five (including a leader who was a confederate). In the subsequent test sessions (which participants attended with their fellow group members), leaders displayed either high or low identity entrepreneurship behaviors. Results indicated that, compared to participants in the low identity entrepreneurship condition, those in the high identity entrepreneurship condition maintained greater effort (maximum heart rate), and demonstrated improved (rather than poorer) performance (average power output in the first 60 seconds of time trials). Examination of pacing showed that the largest increases in participants' average power output occurred in the early stages of their second time trials for those in the high identity entrepreneurship condition only. Results provide causal evidence that leaders who create a shared sense of identity among team members are able to inspire greater participant effort and performance. © 2019 Stevens et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Lower dormancy with rapid germination is an important strategy for seeds in an arid zone with unpredictable rainfall
- Duncan, Corrine, Schultz, Nick, Lewandrowski, Wolfgang, Good, Megan, Cook, Simon
- Authors: Duncan, Corrine , Schultz, Nick , Lewandrowski, Wolfgang , Good, Megan , Cook, Simon
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 9 (2019), p.
- Full Text:
- Reviewed:
- Description: Seed germination traits are key drivers of population dynamics, yet they are under-represented in community ecology studies, which have predominately focussed on adult plant and seed morphological traits. We studied the seed traits and germination strategy of eight woody plant species to investigate regeneration strategies in the arid zone of eastern Australia. To cope with stochastic and minimal rainfall, we predict that arid seeds will either have rapid germination across a wide range of temperatures, improved germination under cooler temperatures, or dormancy and/or longevity traits to delay or stagger germination across time. To understand how temperature affects germination responses, seeds of eight keystone arid species were germinated under laboratory conditions, and under three diurnal temperatures (30/20°C, 25/15°C and 17/7°C) for 30 days. We also tested for decline in seed viability across 24 months in a dry-aging treatment (
- Authors: Duncan, Corrine , Schultz, Nick , Lewandrowski, Wolfgang , Good, Megan , Cook, Simon
- Date: 2019
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 14, no. 9 (2019), p.
- Full Text:
- Reviewed:
- Description: Seed germination traits are key drivers of population dynamics, yet they are under-represented in community ecology studies, which have predominately focussed on adult plant and seed morphological traits. We studied the seed traits and germination strategy of eight woody plant species to investigate regeneration strategies in the arid zone of eastern Australia. To cope with stochastic and minimal rainfall, we predict that arid seeds will either have rapid germination across a wide range of temperatures, improved germination under cooler temperatures, or dormancy and/or longevity traits to delay or stagger germination across time. To understand how temperature affects germination responses, seeds of eight keystone arid species were germinated under laboratory conditions, and under three diurnal temperatures (30/20°C, 25/15°C and 17/7°C) for 30 days. We also tested for decline in seed viability across 24 months in a dry-aging treatment (
Managing uncertainty in movement knowledge for environmental decisions
- Smith, Annabel, Kujala, Heini, Lahoz-Monfort, José, Guja, Lydia, Barton, Philip
- Authors: Smith, Annabel , Kujala, Heini , Lahoz-Monfort, José , Guja, Lydia , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Conservation Letters Vol. 12, no. 3 (2019), p.
- Full Text:
- Reviewed:
- Description: Species’ movements affect their response to environmental change but movement knowledge is often highly uncertain. We now have well-established methods to inte-grate movement knowledge into conservation practice but still lack a framework to deal with uncertainty in movement knowledge for environmental decisions. We provide a framework that distinguishes two dimensions of species’ movement that are heavily influenced by uncertainty: knowledge about movement and relevance of movement to environmental decisions. Management decisions can be informed by their position in this knowledge-relevance space. We then outline a framework to support decisions around (1) increasing understanding of the relevance of movement knowledge, (2) increasing robustness of decisions to uncertainties and (3) improving knowledge on species’ movement. Our decision-support framework provides guid-ance for managing movement-related uncertainty in systematic conservation plan-ning, agri-environment schemes, habitat restoration and international biodiversity policy. It caters to different resource levels (time and funding) so that species’ movement knowledge can be more effectively integrated into environmental decisions. © 2018 The Authors. Conservation Letters published by Wiley Periodicals, Inc.
- Authors: Smith, Annabel , Kujala, Heini , Lahoz-Monfort, José , Guja, Lydia , Barton, Philip
- Date: 2019
- Type: Text , Journal article
- Relation: Conservation Letters Vol. 12, no. 3 (2019), p.
- Full Text:
- Reviewed:
- Description: Species’ movements affect their response to environmental change but movement knowledge is often highly uncertain. We now have well-established methods to inte-grate movement knowledge into conservation practice but still lack a framework to deal with uncertainty in movement knowledge for environmental decisions. We provide a framework that distinguishes two dimensions of species’ movement that are heavily influenced by uncertainty: knowledge about movement and relevance of movement to environmental decisions. Management decisions can be informed by their position in this knowledge-relevance space. We then outline a framework to support decisions around (1) increasing understanding of the relevance of movement knowledge, (2) increasing robustness of decisions to uncertainties and (3) improving knowledge on species’ movement. Our decision-support framework provides guid-ance for managing movement-related uncertainty in systematic conservation plan-ning, agri-environment schemes, habitat restoration and international biodiversity policy. It caters to different resource levels (time and funding) so that species’ movement knowledge can be more effectively integrated into environmental decisions. © 2018 The Authors. Conservation Letters published by Wiley Periodicals, Inc.
National income inequality predicts cultural variation in mouth to mouth kissing
- Watkins, Christopher, Leongómez, Juan, Bovet, Jeanne, Żelaźniewicz, Agnieszka, Korbmacher, Max, Varella, Marco, Fernandez, Ana, Wagstaff, Danielle, Bolgan, Samuela
- Authors: Watkins, Christopher , Leongómez, Juan , Bovet, Jeanne , Żelaźniewicz, Agnieszka , Korbmacher, Max , Varella, Marco , Fernandez, Ana , Wagstaff, Danielle , Bolgan, Samuela
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p. 1-9
- Full Text:
- Reviewed:
- Description: Romantic mouth-to-mouth kissing is culturally widespread, although not a human universal, and may play a functional role in assessing partner health and maintaining long-term pair bonds. Use and appreciation of kissing may therefore vary according to whether the environment places a premium on good health and partner investment. Here, we test for cultural variation (13 countries from six continents) in these behaviours/attitudes according to national health (historical pathogen prevalence) and both absolute (GDP) and relative wealth (GINI). Our data reveal that kissing is valued more in established relationships than it is valued during courtship. Also, consistent with the pair bonding hypothesis of the function of romantic kissing, relative poverty (income inequality) predicts frequency of kissing across romantic relationships. When aggregated, the predicted relationship between income inequality and kissing frequency (r = 0.67, BCa 95% CI[0.32,0.89]) was over five times the size of the null correlations between income inequality and frequency of hugging/cuddling and sex. As social complexity requires monitoring resource competition among large groups and predicts kissing prevalence in remote societies, this gesture may be important in the maintenance of long-term pair bonds in specific environments.
- Authors: Watkins, Christopher , Leongómez, Juan , Bovet, Jeanne , Żelaźniewicz, Agnieszka , Korbmacher, Max , Varella, Marco , Fernandez, Ana , Wagstaff, Danielle , Bolgan, Samuela
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p. 1-9
- Full Text:
- Reviewed:
- Description: Romantic mouth-to-mouth kissing is culturally widespread, although not a human universal, and may play a functional role in assessing partner health and maintaining long-term pair bonds. Use and appreciation of kissing may therefore vary according to whether the environment places a premium on good health and partner investment. Here, we test for cultural variation (13 countries from six continents) in these behaviours/attitudes according to national health (historical pathogen prevalence) and both absolute (GDP) and relative wealth (GINI). Our data reveal that kissing is valued more in established relationships than it is valued during courtship. Also, consistent with the pair bonding hypothesis of the function of romantic kissing, relative poverty (income inequality) predicts frequency of kissing across romantic relationships. When aggregated, the predicted relationship between income inequality and kissing frequency (r = 0.67, BCa 95% CI[0.32,0.89]) was over five times the size of the null correlations between income inequality and frequency of hugging/cuddling and sex. As social complexity requires monitoring resource competition among large groups and predicts kissing prevalence in remote societies, this gesture may be important in the maintenance of long-term pair bonds in specific environments.
Response of Chloris truncata to moisture stress, elevated carbon dioxide and herbicide application
- Weller, Sandra, Florentine, Singarayer, Mutti, Navneet, Jha, Prashant, Chauhan, Bhagirath
- Authors: Weller, Sandra , Florentine, Singarayer , Mutti, Navneet , Jha, Prashant , Chauhan, Bhagirath
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p. 1-10
- Full Text:
- Reviewed:
- Description: Herbicide resistance has been observed in Chloris truncata, an Australian native C4 grass and a summer-fallow weed, which is common in no-till agriculture situations where herbicides are involved in crop management. To investigate the role of drought and increased atmospheric carbon dioxide (CO2) in determining weed growth, three trials were conducted using a ‘glyphosate-resistant’ and a ‘glyphosate-susceptible’ biotype. The first two trials tested the effect of herbicide (glyphosate) application on plant survival and growth under moisture stress and elevated CO2 respectively. A third trial investigated the effect on plant growth and reproduction under conditions of moisture stress and elevated CO2 in the absence of herbicide. In the first trial, water was withheld from half of the plants prior to application of glyphosate to all plants, and in the second trial plants were grown in either ambient (450 ppm) or elevated CO2 levels (750 ppm) prior to, and following, herbicide application. In both biotypes, herbicide effectiveness was reduced when plants were subjected to moisture stress or if grown in elevated CO2. Plant productivity, as measured by dry biomass per plant, was reduced with moisture stress, but increased with elevated CO2. In the third trial, growth rate, biomass and seed production were higher in the susceptible biotype compared to the resistant biotype. This suggests that a superior ability to resist herbicides may come at a cost to overall plant fitness. The results indicate that control of this weed may become difficult in the future as climatic conditions change. Supplementary information accompanies this paper at https://doi.org/10.1038/s41598-019-47237-x.
- Authors: Weller, Sandra , Florentine, Singarayer , Mutti, Navneet , Jha, Prashant , Chauhan, Bhagirath
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p. 1-10
- Full Text:
- Reviewed:
- Description: Herbicide resistance has been observed in Chloris truncata, an Australian native C4 grass and a summer-fallow weed, which is common in no-till agriculture situations where herbicides are involved in crop management. To investigate the role of drought and increased atmospheric carbon dioxide (CO2) in determining weed growth, three trials were conducted using a ‘glyphosate-resistant’ and a ‘glyphosate-susceptible’ biotype. The first two trials tested the effect of herbicide (glyphosate) application on plant survival and growth under moisture stress and elevated CO2 respectively. A third trial investigated the effect on plant growth and reproduction under conditions of moisture stress and elevated CO2 in the absence of herbicide. In the first trial, water was withheld from half of the plants prior to application of glyphosate to all plants, and in the second trial plants were grown in either ambient (450 ppm) or elevated CO2 levels (750 ppm) prior to, and following, herbicide application. In both biotypes, herbicide effectiveness was reduced when plants were subjected to moisture stress or if grown in elevated CO2. Plant productivity, as measured by dry biomass per plant, was reduced with moisture stress, but increased with elevated CO2. In the third trial, growth rate, biomass and seed production were higher in the susceptible biotype compared to the resistant biotype. This suggests that a superior ability to resist herbicides may come at a cost to overall plant fitness. The results indicate that control of this weed may become difficult in the future as climatic conditions change. Supplementary information accompanies this paper at https://doi.org/10.1038/s41598-019-47237-x.
Review of tropical cyclones in the Australian region : Climatology, variability, predictability, and trends
- Chand, Savin, Dowdy, Andrew, Ramsay, Hamish, Walsh, Kevin, Tory, Kevin, Power, Scott, Bell, Samuel, Lavender, Sally, Ye, Hua, Kuleshov, Yuri
- Authors: Chand, Savin , Dowdy, Andrew , Ramsay, Hamish , Walsh, Kevin , Tory, Kevin , Power, Scott , Bell, Samuel , Lavender, Sally , Ye, Hua , Kuleshov, Yuri
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Wiley Interdisciplinary Reviews: Climate Change Vol. 10, no. 5 (2019), p. 1-17
- Full Text:
- Reviewed:
- Description: Tropical cyclones (TCs) can have severe impacts on Australia. These include extreme rainfall and winds, and coastal hazards such as destructive waves, storm surges, estuarine flooding, and coastal erosion. Various aspects of TCs in the Australian region have been documented over the past several decades. In recent years, increasing emphasis has been placed on human-induced climate change effects on TCs in the Australian region and elsewhere around the globe. However, large natural variability and the lack of consistent long-term TC observations have often complicated the detection and attribution of TC trends. Efforts have been made to improve TC records for Australia over the past decades, but it is still unclear whether such records are sufficient to provide better understanding of the impacts of natural climate variability and climate change. It is important to note that the damage costs associated with tropical cyclones in Australia have increased in recent decades and will continue to increase due to growing coastal settlement and infrastructure development. Therefore, it is critical that any coastal infrastructure planning and engineering decisions, as well as disaster management decisions, strongly consider future risks from tropical cyclones. A better understanding of tropical cyclones in a changing climate will provide key insights that can help mitigate impacts of tropical cyclones on vulnerable communities. An objective assessment of the Australian TCs at regional scale and its link with climate variability and change using improved and up-to-date data records is more imperative now than before. This article is categorized under: Paleoclimates and Current Trends > Modern Climate Change.
- Authors: Chand, Savin , Dowdy, Andrew , Ramsay, Hamish , Walsh, Kevin , Tory, Kevin , Power, Scott , Bell, Samuel , Lavender, Sally , Ye, Hua , Kuleshov, Yuri
- Date: 2019
- Type: Text , Journal article , Review
- Relation: Wiley Interdisciplinary Reviews: Climate Change Vol. 10, no. 5 (2019), p. 1-17
- Full Text:
- Reviewed:
- Description: Tropical cyclones (TCs) can have severe impacts on Australia. These include extreme rainfall and winds, and coastal hazards such as destructive waves, storm surges, estuarine flooding, and coastal erosion. Various aspects of TCs in the Australian region have been documented over the past several decades. In recent years, increasing emphasis has been placed on human-induced climate change effects on TCs in the Australian region and elsewhere around the globe. However, large natural variability and the lack of consistent long-term TC observations have often complicated the detection and attribution of TC trends. Efforts have been made to improve TC records for Australia over the past decades, but it is still unclear whether such records are sufficient to provide better understanding of the impacts of natural climate variability and climate change. It is important to note that the damage costs associated with tropical cyclones in Australia have increased in recent decades and will continue to increase due to growing coastal settlement and infrastructure development. Therefore, it is critical that any coastal infrastructure planning and engineering decisions, as well as disaster management decisions, strongly consider future risks from tropical cyclones. A better understanding of tropical cyclones in a changing climate will provide key insights that can help mitigate impacts of tropical cyclones on vulnerable communities. An objective assessment of the Australian TCs at regional scale and its link with climate variability and change using improved and up-to-date data records is more imperative now than before. This article is categorized under: Paleoclimates and Current Trends > Modern Climate Change.
Seed germination ecology of Bidens pilosa and its implications for weed management
- Chauhan, Bhagirath, Ali, Hafiz, Florentine, Singarayer
- Authors: Chauhan, Bhagirath , Ali, Hafiz , Florentine, Singarayer
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p.
- Full Text:
- Reviewed:
- Description: It is now widely recognized that Bidens pilosa has become a problematic broadleaf weed in many ecosystems across the world and, particularly in the light of recent climate change conditions, closer management strategies are required to curtail its impact on agricultural cropping. In this investigation, experiments were conducted to evaluate the effect of environmental factors on the germination and emergence of B. pilosa, and also on the response of this weed to commonly available post-emergence herbicides in Australia. The environmental factors of particular interest to this current work were the effect of light and temperature, salinity, burial depth and moisture on B. pilosa since these are key management issues in Australian agriculture. In addition, the effects of a number of commonly used herbicides were examined, because of concerns regarding emerging herbicide resistance. In the tested light/dark regimes, germination was found to be higher at fluctuating day/night temperatures of 25/15 °C and 30/20 °C (92–93%) than at 35/25 °C (79%), whilst across the different temperature ranges, germination was higher in the light/dark regime (79–93%) than in complete darkness (22–38%). The standard five-minute temperature pretreatment required for 50% inhibition of maximum germination was found to be 160 °C, and it was further shown that no seeds germinated at temperatures higher than 240 °C. With regard to salinity, some B. pilosa seeds germinated (3%) in 200 mM sodium chloride (NaCl) but all failed to germinate at 250 mM NaCl. Germination declined from 89% to 2% as the external osmotic potential decreased from 0 to −0.6 MPa, and germination ceased at −0.8 MPa. Seeding emergence of B. pilosa was maximum (71%) for seeds placed on the soil surface and it was found that no seedlings emerged from a depth of 8 cm or greater. A depth of 3.75 cm was required to inhibit the seeds to 50% of the maximum emergence. In this study, application of glufosinate, glyphosate and paraquat provided commercially acceptable control levels (generally accepted as >90%) when applied at the four-leaf stage of B. pilosa. However, none of the herbicide treatments involved in this study provided this level of control when applied at the six-leaf stage. In summary, B. pilosa germination has been clearly shown to be stimulated by light and thus its emergence was greatest from the soil surface. This suggests that infestation from this weed will remain as a problem in no-till conservation agriculture systems, the use of which is increasing now throughout the world. It is intended that information generated from this study be used to develop more effective integrated management programs for B. pilosa and similar weeds in commercial agricultural environments which are tending toward conservation approaches. © 2019, The Author(s).
- Authors: Chauhan, Bhagirath , Ali, Hafiz , Florentine, Singarayer
- Date: 2019
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 9, no. 1 (2019), p.
- Full Text:
- Reviewed:
- Description: It is now widely recognized that Bidens pilosa has become a problematic broadleaf weed in many ecosystems across the world and, particularly in the light of recent climate change conditions, closer management strategies are required to curtail its impact on agricultural cropping. In this investigation, experiments were conducted to evaluate the effect of environmental factors on the germination and emergence of B. pilosa, and also on the response of this weed to commonly available post-emergence herbicides in Australia. The environmental factors of particular interest to this current work were the effect of light and temperature, salinity, burial depth and moisture on B. pilosa since these are key management issues in Australian agriculture. In addition, the effects of a number of commonly used herbicides were examined, because of concerns regarding emerging herbicide resistance. In the tested light/dark regimes, germination was found to be higher at fluctuating day/night temperatures of 25/15 °C and 30/20 °C (92–93%) than at 35/25 °C (79%), whilst across the different temperature ranges, germination was higher in the light/dark regime (79–93%) than in complete darkness (22–38%). The standard five-minute temperature pretreatment required for 50% inhibition of maximum germination was found to be 160 °C, and it was further shown that no seeds germinated at temperatures higher than 240 °C. With regard to salinity, some B. pilosa seeds germinated (3%) in 200 mM sodium chloride (NaCl) but all failed to germinate at 250 mM NaCl. Germination declined from 89% to 2% as the external osmotic potential decreased from 0 to −0.6 MPa, and germination ceased at −0.8 MPa. Seeding emergence of B. pilosa was maximum (71%) for seeds placed on the soil surface and it was found that no seedlings emerged from a depth of 8 cm or greater. A depth of 3.75 cm was required to inhibit the seeds to 50% of the maximum emergence. In this study, application of glufosinate, glyphosate and paraquat provided commercially acceptable control levels (generally accepted as >90%) when applied at the four-leaf stage of B. pilosa. However, none of the herbicide treatments involved in this study provided this level of control when applied at the six-leaf stage. In summary, B. pilosa germination has been clearly shown to be stimulated by light and thus its emergence was greatest from the soil surface. This suggests that infestation from this weed will remain as a problem in no-till conservation agriculture systems, the use of which is increasing now throughout the world. It is intended that information generated from this study be used to develop more effective integrated management programs for B. pilosa and similar weeds in commercial agricultural environments which are tending toward conservation approaches. © 2019, The Author(s).
Singlet molecular oxygen regulates vascular tone and blood pressure in inflammation
- Stanley, Christopher, Maghzal, Ghassan, Ayer, Anita, Talib, Jihan, Giltrap, Andrew, Shengule, Sudhir, Wolhuter, Kathryn, Wang, Yutang, Chadha, Preet, Suarna, Cacang, Prysyazhna, Oleksandra, Scotcher, Jenna, Dunn, Louise, Prado, Fernanda, Nguyen, Nghi, Odiba, Jephthah, Baell, Johathan, Stasch, Johannes-Peter, Yamamoto, Yorihiro, Di Mascio, Paolo, Eaton, Philip, Payne, Richard, Stocker, Roland
- Authors: Stanley, Christopher , Maghzal, Ghassan , Ayer, Anita , Talib, Jihan , Giltrap, Andrew , Shengule, Sudhir , Wolhuter, Kathryn , Wang, Yutang , Chadha, Preet , Suarna, Cacang , Prysyazhna, Oleksandra , Scotcher, Jenna , Dunn, Louise , Prado, Fernanda , Nguyen, Nghi , Odiba, Jephthah , Baell, Johathan , Stasch, Johannes-Peter , Yamamoto, Yorihiro , Di Mascio, Paolo , Eaton, Philip , Payne, Richard , Stocker, Roland
- Date: 2019
- Type: Text , Journal article , Letter
- Relation: Nature Vol. 566, no. 7745 (2019), p. 548-552
- Full Text:
- Reviewed:
- Description: Singlet molecular oxygen (O-1(2)) has well-established roles in photosynthetic plants, bacteria and fungi(1-3), but not in mammals. Chemically generated O-1(2) oxidizes the amino acid tryptophan to precursors of a key metabolite called N-formylkynurenine(4), whereas enzymatic oxidation of tryptophan to N-formylkynurenine is catalysed by a family of dioxygenases, including indoleamine 2,3-dioxygenase 1(5). Under inflammatory conditions, this haem-containing enzyme is expressed in arterial endothelial cells, where it contributes to the regulation of blood pressure(6). However, whether indoleamine 2,3-dioxygenase 1 forms O-1(2) and whether this contributes to blood pressure control have remained unknown. Here we show that arterial indoleamine 2,3-dioxygenase 1 regulates blood pressure via formation of O-1(2). We observed that in the presence of hydrogen peroxide, the enzyme generates O-1(2) and that this is associated with the stereoselective oxidation of L-tryptophan to a tricyclic hydroperoxide via a previously unrecognized oxidative activation of the dioxygenase activity. The tryptophan-derived hydroperoxide acts in vivo as a signalling molecule, inducing arterial relaxation and decreasing blood pressure; this activity is dependent on Cys42 of protein kinase G1 alpha. Our findings demonstrate a pathophysiological role for O-1(2) in mammals through formation of an amino acid-derived hydroperoxide that regulates vascular tone and blood pressure under inflammatory conditions.
- Authors: Stanley, Christopher , Maghzal, Ghassan , Ayer, Anita , Talib, Jihan , Giltrap, Andrew , Shengule, Sudhir , Wolhuter, Kathryn , Wang, Yutang , Chadha, Preet , Suarna, Cacang , Prysyazhna, Oleksandra , Scotcher, Jenna , Dunn, Louise , Prado, Fernanda , Nguyen, Nghi , Odiba, Jephthah , Baell, Johathan , Stasch, Johannes-Peter , Yamamoto, Yorihiro , Di Mascio, Paolo , Eaton, Philip , Payne, Richard , Stocker, Roland
- Date: 2019
- Type: Text , Journal article , Letter
- Relation: Nature Vol. 566, no. 7745 (2019), p. 548-552
- Full Text:
- Reviewed:
- Description: Singlet molecular oxygen (O-1(2)) has well-established roles in photosynthetic plants, bacteria and fungi(1-3), but not in mammals. Chemically generated O-1(2) oxidizes the amino acid tryptophan to precursors of a key metabolite called N-formylkynurenine(4), whereas enzymatic oxidation of tryptophan to N-formylkynurenine is catalysed by a family of dioxygenases, including indoleamine 2,3-dioxygenase 1(5). Under inflammatory conditions, this haem-containing enzyme is expressed in arterial endothelial cells, where it contributes to the regulation of blood pressure(6). However, whether indoleamine 2,3-dioxygenase 1 forms O-1(2) and whether this contributes to blood pressure control have remained unknown. Here we show that arterial indoleamine 2,3-dioxygenase 1 regulates blood pressure via formation of O-1(2). We observed that in the presence of hydrogen peroxide, the enzyme generates O-1(2) and that this is associated with the stereoselective oxidation of L-tryptophan to a tricyclic hydroperoxide via a previously unrecognized oxidative activation of the dioxygenase activity. The tryptophan-derived hydroperoxide acts in vivo as a signalling molecule, inducing arterial relaxation and decreasing blood pressure; this activity is dependent on Cys42 of protein kinase G1 alpha. Our findings demonstrate a pathophysiological role for O-1(2) in mammals through formation of an amino acid-derived hydroperoxide that regulates vascular tone and blood pressure under inflammatory conditions.
Trans-ethnic kidney function association study reveals putative causal genes and effects on kidney-specific disease aetiologies
- Morris, Andrew, Le, Thu, Wu, Haojia, Akbarov, Artur, van der Most, Peter, Hemani, Gibran, Smith, George, Mahajan, Anubha, Gaulton, Kyle, Nadkarni, Girish, Valladares-Salgado, Adan, Wacher-Rodarte, Niels, Mychaleckyj, Josyf, Dueker, Nicole, Guo, Xiuqing, Hai, Yang, Haessler, Jeffrey, Kamatani, Yoichiro, Stilp, Adrienne, Zhu, Gu, Cook, James, Arnlov, Johan, Blanton, Susan, de Borst, Martin, Bottinger, Erwin, Buchanan, Thomas, Cechova, Sylvia, Charchar, Fadi, Chu, Pei-Lun, Damman, Jeffrey, Eales, James, Gharavi, Ali, Giedraitis, Vilmantas, Heath, Andrew, Ipp, Eli, Kiryluk, Krzysztof, Kramer, Holly, Kubo, Michiaki, Larsson, Anders, Lindgren, Cecilia, Lu, Yingchang, Madden, Pamela, Montgomery, Grant, Papanicolaou, George, Raffel, Leslie, Sacco, Ralph, Sanchez, Elena, Stark, Holger, Sundstrom, Johan, Taylor, Kent, Xiang, Anny, Zivkovic, Aleksandra, Lind, Lars, Ingelsson, Erik, Martin, Nicholas, Whitfield, John, Cai, Jianwen, Laurie, Cathy, Okada, Yukinori, Matsuda, Koichi, Kooperberg, Charles, Chen, Yii-Der, Rundek, Tatjana, Rich, Stephen, Loos, Ruth, Parra, Esteban, Cruz, Miguel, Rotter, Jerome, Snieder, Harold, Tomaszewski, Maciej, Humphreys, Benjamin, Franceschini, Nora
- Authors: Morris, Andrew , Le, Thu , Wu, Haojia , Akbarov, Artur , van der Most, Peter , Hemani, Gibran , Smith, George , Mahajan, Anubha , Gaulton, Kyle , Nadkarni, Girish , Valladares-Salgado, Adan , Wacher-Rodarte, Niels , Mychaleckyj, Josyf , Dueker, Nicole , Guo, Xiuqing , Hai, Yang , Haessler, Jeffrey , Kamatani, Yoichiro , Stilp, Adrienne , Zhu, Gu , Cook, James , Arnlov, Johan , Blanton, Susan , de Borst, Martin , Bottinger, Erwin , Buchanan, Thomas , Cechova, Sylvia , Charchar, Fadi , Chu, Pei-Lun , Damman, Jeffrey , Eales, James , Gharavi, Ali , Giedraitis, Vilmantas , Heath, Andrew , Ipp, Eli , Kiryluk, Krzysztof , Kramer, Holly , Kubo, Michiaki , Larsson, Anders , Lindgren, Cecilia , Lu, Yingchang , Madden, Pamela , Montgomery, Grant , Papanicolaou, George , Raffel, Leslie , Sacco, Ralph , Sanchez, Elena , Stark, Holger , Sundstrom, Johan , Taylor, Kent , Xiang, Anny , Zivkovic, Aleksandra , Lind, Lars , Ingelsson, Erik , Martin, Nicholas , Whitfield, John , Cai, Jianwen , Laurie, Cathy , Okada, Yukinori , Matsuda, Koichi , Kooperberg, Charles , Chen, Yii-Der , Rundek, Tatjana , Rich, Stephen , Loos, Ruth , Parra, Esteban , Cruz, Miguel , Rotter, Jerome , Snieder, Harold , Tomaszewski, Maciej , Humphreys, Benjamin , Franceschini, Nora
- Date: 2019
- Type: Text , Journal article
- Relation: Nature Communications Vol. 10, no. 1 (2019), p. 1-14
- Full Text:
- Reviewed:
- Description: Chronic kidney disease (CKD) affects ~10% of the global population, with considerable ethnic differences in prevalence and aetiology. We assemble genome-wide association studies of estimated glomerular filtration rate (eGFR), a measure of kidney function that defines CKD, in 312,468 individuals of diverse ancestry. We identify 127 distinct association signals with homogeneous effects on eGFR across ancestries and enrichment in genomic annotations including kidney-specific histone modifications. Fine-mapping reveals 40 high-confidence variants driving eGFR associations and highlights putative causal genes with cell-type specific expression in glomerulus, and in proximal and distal nephron. Mendelian randomisation supports causal effects of eGFR on overall and cause-specific CKD, kidney stone formation, diastolic blood pressure and hypertension. These results define novel molecular mechanisms and putative causal genes for eGFR, offering insight into clinical outcomes and routes to CKD treatment development.
- Authors: Morris, Andrew , Le, Thu , Wu, Haojia , Akbarov, Artur , van der Most, Peter , Hemani, Gibran , Smith, George , Mahajan, Anubha , Gaulton, Kyle , Nadkarni, Girish , Valladares-Salgado, Adan , Wacher-Rodarte, Niels , Mychaleckyj, Josyf , Dueker, Nicole , Guo, Xiuqing , Hai, Yang , Haessler, Jeffrey , Kamatani, Yoichiro , Stilp, Adrienne , Zhu, Gu , Cook, James , Arnlov, Johan , Blanton, Susan , de Borst, Martin , Bottinger, Erwin , Buchanan, Thomas , Cechova, Sylvia , Charchar, Fadi , Chu, Pei-Lun , Damman, Jeffrey , Eales, James , Gharavi, Ali , Giedraitis, Vilmantas , Heath, Andrew , Ipp, Eli , Kiryluk, Krzysztof , Kramer, Holly , Kubo, Michiaki , Larsson, Anders , Lindgren, Cecilia , Lu, Yingchang , Madden, Pamela , Montgomery, Grant , Papanicolaou, George , Raffel, Leslie , Sacco, Ralph , Sanchez, Elena , Stark, Holger , Sundstrom, Johan , Taylor, Kent , Xiang, Anny , Zivkovic, Aleksandra , Lind, Lars , Ingelsson, Erik , Martin, Nicholas , Whitfield, John , Cai, Jianwen , Laurie, Cathy , Okada, Yukinori , Matsuda, Koichi , Kooperberg, Charles , Chen, Yii-Der , Rundek, Tatjana , Rich, Stephen , Loos, Ruth , Parra, Esteban , Cruz, Miguel , Rotter, Jerome , Snieder, Harold , Tomaszewski, Maciej , Humphreys, Benjamin , Franceschini, Nora
- Date: 2019
- Type: Text , Journal article
- Relation: Nature Communications Vol. 10, no. 1 (2019), p. 1-14
- Full Text:
- Reviewed:
- Description: Chronic kidney disease (CKD) affects ~10% of the global population, with considerable ethnic differences in prevalence and aetiology. We assemble genome-wide association studies of estimated glomerular filtration rate (eGFR), a measure of kidney function that defines CKD, in 312,468 individuals of diverse ancestry. We identify 127 distinct association signals with homogeneous effects on eGFR across ancestries and enrichment in genomic annotations including kidney-specific histone modifications. Fine-mapping reveals 40 high-confidence variants driving eGFR associations and highlights putative causal genes with cell-type specific expression in glomerulus, and in proximal and distal nephron. Mendelian randomisation supports causal effects of eGFR on overall and cause-specific CKD, kidney stone formation, diastolic blood pressure and hypertension. These results define novel molecular mechanisms and putative causal genes for eGFR, offering insight into clinical outcomes and routes to CKD treatment development.
A review of the scaled boundary finite element method for two-dimensional linear elastic fracture mechanics
- Song, Chongmin, Ooi, Ean Tat, Natarajan, Sundararajan
- Authors: Song, Chongmin , Ooi, Ean Tat , Natarajan, Sundararajan
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Engineering Fracture Mechanics Vol. 187, no. (2018), p. 45-73
- Full Text:
- Reviewed:
- Description: The development and the application of the scaled boundary finite element method for fracture analysis is reviewed. In this method, polygonal elements (referred to as subdomains) of arbitrary number of edges are constructed, with the only limitation that the whole boundary is directly visible from the scaling centre. The element solution is semi-analytical. When applied to two-dimensional linear fracture mechanics, any kinds of stress singularities are represented analytically without local refinement, special elements and enrichment functions. The flexibility of polygons to represent arbitrary geometric shapes leads to simple yet efficient remeshing algorithms to model crack propagation. Coupling procedures with the extended finite element method, meshless method and boundary element method to handle changes in the crack morphology have been established. These developments result in an efficient framework for fracture modelling. Examples of applications are provided to demonstrate their feasibility. © 2017 Elsevier Ltd
- Authors: Song, Chongmin , Ooi, Ean Tat , Natarajan, Sundararajan
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Engineering Fracture Mechanics Vol. 187, no. (2018), p. 45-73
- Full Text:
- Reviewed:
- Description: The development and the application of the scaled boundary finite element method for fracture analysis is reviewed. In this method, polygonal elements (referred to as subdomains) of arbitrary number of edges are constructed, with the only limitation that the whole boundary is directly visible from the scaling centre. The element solution is semi-analytical. When applied to two-dimensional linear fracture mechanics, any kinds of stress singularities are represented analytically without local refinement, special elements and enrichment functions. The flexibility of polygons to represent arbitrary geometric shapes leads to simple yet efficient remeshing algorithms to model crack propagation. Coupling procedures with the extended finite element method, meshless method and boundary element method to handle changes in the crack morphology have been established. These developments result in an efficient framework for fracture modelling. Examples of applications are provided to demonstrate their feasibility. © 2017 Elsevier Ltd
Altered populations of unconventional T Cell lineages in patients with Langerhans Cell Histiocytosis
- Mitchell, Jenée, Kvedaraite, Egle, von Bahr Greenwood, Tatiana, Henter, Jan-Inge, Pellicci, Daniel, Berzins, Stuart, Kannourakis, George
- Authors: Mitchell, Jenée , Kvedaraite, Egle , von Bahr Greenwood, Tatiana , Henter, Jan-Inge , Pellicci, Daniel , Berzins, Stuart , Kannourakis, George
- Date: 2018
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 8, no. 1 (2018), p. 1-13
- Full Text:
- Reviewed:
- Description: Langerhans cell histiocytosis (LCH) lesions are defined by the presence of CD1a+/CD207+ myeloid cells, but many other immune cells are present including unconventional T cells, which have powerful immunoregulatory functions. Unconventional T cell lineages include mucosal-associated invariant T (MAIT) cells, type I natural killer T (NKT) cells and gamma-delta (γδ) T cells, which are associated with many inflammatory conditions, although their importance has not been studied in LCH. We characterized their phenotype and function in blood and lesions from patients with LCH, and identified a deficiency in MAIT cell frequency and abnormalities in the subset distributions of γδ T cells and NKT cells. Such abnormalities are associated with immune dysregulation in other disease settings and are therefore potentially important in LCH. Our study is the first to recognize alterations to MAIT cell proportions in patients with LCH. This finding along with other abnormalities identified amongst unconventional T cells could potentially influence the onset and progression of LCH, thereby highlighting potential targets for new immune based therapies.
Altered populations of unconventional T Cell lineages in patients with Langerhans Cell Histiocytosis
- Authors: Mitchell, Jenée , Kvedaraite, Egle , von Bahr Greenwood, Tatiana , Henter, Jan-Inge , Pellicci, Daniel , Berzins, Stuart , Kannourakis, George
- Date: 2018
- Type: Text , Journal article
- Relation: Scientific Reports Vol. 8, no. 1 (2018), p. 1-13
- Full Text:
- Reviewed:
- Description: Langerhans cell histiocytosis (LCH) lesions are defined by the presence of CD1a+/CD207+ myeloid cells, but many other immune cells are present including unconventional T cells, which have powerful immunoregulatory functions. Unconventional T cell lineages include mucosal-associated invariant T (MAIT) cells, type I natural killer T (NKT) cells and gamma-delta (γδ) T cells, which are associated with many inflammatory conditions, although their importance has not been studied in LCH. We characterized their phenotype and function in blood and lesions from patients with LCH, and identified a deficiency in MAIT cell frequency and abnormalities in the subset distributions of γδ T cells and NKT cells. Such abnormalities are associated with immune dysregulation in other disease settings and are therefore potentially important in LCH. Our study is the first to recognize alterations to MAIT cell proportions in patients with LCH. This finding along with other abnormalities identified amongst unconventional T cells could potentially influence the onset and progression of LCH, thereby highlighting potential targets for new immune based therapies.
Charles Joseph La Trobe and his administration of the Wadawurrung, 1839‑1853
- Authors: Cahir, David (Fred)
- Date: 2018
- Type: Text , Journal article
- Relation: Journal of the C.J. La Trobe Society Vol. 17, no. 1 (2018), p. 5-16
- Full Text:
- Reviewed:
- Description: Maggie Black’s work as a writer has focused on disadvantaged people in Africa, Asia and Latin America. Her view of the damaging impact of contemporary forms of development on Indigenous societies is articulated in her book, International Development: Illusions and Realities (New Internationalist, 2015). This proved a useful basis for studying her great‑grandfather’s pioneering life in Victoria. Niel Black’s archive found its way to State Library Victoria thanks to Margaret Kiddle, author of Men of Yesterday (Melbourne University Press, 1961), which also drew heavily on his remarkable voice. This article is a shortened version of a chapter in the author’s Up Came a Squatter: Niel Black of Glenormiston 1839‑1880 (NewSouth, 2016).
- Authors: Cahir, David (Fred)
- Date: 2018
- Type: Text , Journal article
- Relation: Journal of the C.J. La Trobe Society Vol. 17, no. 1 (2018), p. 5-16
- Full Text:
- Reviewed:
- Description: Maggie Black’s work as a writer has focused on disadvantaged people in Africa, Asia and Latin America. Her view of the damaging impact of contemporary forms of development on Indigenous societies is articulated in her book, International Development: Illusions and Realities (New Internationalist, 2015). This proved a useful basis for studying her great‑grandfather’s pioneering life in Victoria. Niel Black’s archive found its way to State Library Victoria thanks to Margaret Kiddle, author of Men of Yesterday (Melbourne University Press, 1961), which also drew heavily on his remarkable voice. This article is a shortened version of a chapter in the author’s Up Came a Squatter: Niel Black of Glenormiston 1839‑1880 (NewSouth, 2016).