171 results on '"Andrew J. Hamilton"'
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2. Comparison of Air-Wedge Shearing vs Mach-Zehnder Interferometric Methods for Plasma Parameter Measurements
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Matthew L. Rustad, Andrew J. Hamilton, James E. Caplinger, and Vladimir I. Sotnikov
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- 2022
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3. Vegetable cultivation as a diversification option for fruit farmers in the Goulburn Valley, Australia
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Malwinder Singh Pandher, Dorin Gupta, Gayathri Devi Mekala, Andrew J. Hamilton, Brian Davidson, Megan Hill, Darla Hatton MacDonald, and Aimee McCutcheon
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Economics and Econometrics ,Agricultural diversification ,Restructuring ,business.industry ,Agroforestry ,04 agricultural and veterinary sciences ,010501 environmental sciences ,Diversification (marketing strategy) ,01 natural sciences ,Water scarcity ,Geography ,Pome ,Agriculture ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,business ,Agronomy and Crop Science ,0105 earth and related environmental sciences - Abstract
Worldwide, water scarcity, profit-cost pressure and restructuring of agricultural markets have led to on-farm diversification. The Goulburn Valley’s (GV) pome and stone fruit farms, in the Murray-D...
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- 2021
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4. Precision Health Analytics With Predictive Analytics and Implementation Research
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Muin J. Khoury, Matthew T. Quinn, Michael M. Engelgau, George J. Papanicolaou, Lucy L. Hsu, Lorens A. Helmchen, David M. Kent, Rebecca A. Roper, John Kravitz, Craig H. Blakely, Marishka K. Brown, Le Shawndra N. Price, Kathleen N. Fenton, Melissa Green Parker, Amy J.H. Kind, Paula K. Shireman, George A. Mensah, Andrew J. Hamilton, Robert M. Califf, Thomas A. Pearson, Rhonda D. Szczesniak, Thomas L. Croxton, Carmela Alcántara, David C. Goff, Sharon M. Smith, Cheryl Anne Boyce, and Mattia Prosperi
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medicine.medical_specialty ,business.industry ,Public health ,media_common.quotation_subject ,Context (language use) ,030204 cardiovascular system & hematology ,Predictive analytics ,Precision medicine ,Data science ,03 medical and health sciences ,0302 clinical medicine ,Analytics ,Health care ,Medicine ,Quality (business) ,030212 general & internal medicine ,Implementation research ,Cardiology and Cardiovascular Medicine ,business ,media_common - Abstract
Emerging data science techniques of predictive analytics expand the quality and quantity of complex data relevant to human health and provide opportunities for understanding and control of conditions such as heart, lung, blood, and sleep disorders. To realize these opportunities, the information sources, the data science tools that use the information, and the application of resulting analytics to health and health care issues will require implementation research methods to define benefits, harms, reach, and sustainability; and to understand related resource utilization implications to inform policymakers. This JACC State-of-the-Art Review is based on a workshop convened by the National Heart, Lung, and Blood Institute to explore predictive analytics in the context of implementation science. It highlights precision medicine and precision public health as complementary and compelling applications of predictive analytics, and addresses future research and training endeavors that might further foster the application of predictive analytics in clinical medicine and public health.
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- 2020
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5. Parameter uncertainty, sensitivity analysis and prediction error in a water-balance hydrological model.
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Kurt K. Benke, Kim E. Lowell, and Andrew J. Hamilton
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- 2008
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6. A highly species-rich jaw-bone artefact from New Guinea
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Bronwyn Hopwood and Andrew J Hamilton
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Archeology ,biology ,Anthropology ,Echymipera rufescens ,Mandible ,Echymipera clara ,New guinea ,Assemblage (archaeology) ,Zoology ,Jaw bone ,biology.organism_classification ,Pseudochirulus canescens ,Marsupial - Abstract
An unusual jaw-bone artefact from the north-western lowlands, West Sepik Province, Papua New Guinea, is described. It comprises 11 clusters of jawbones as well as a pendant of shell and a ring of bone. The clusters are separated by crab legs, and the entire assemblage is threaded on string. Ten of the clusters have four marsupial dentaries each, and one has three. One cluster also hosts a snake mandible, and another the mandible of an unidentified reptile. The marsupial species identified are Echymipera rufescens, Echymipera clara, Phalangista naudicaudatus, Pseudochirulus canescens and Pseudochirulus canescens. A model based on the Second (or Area) Moment of Inertia suggests that the ring of bone might be from a human tibia or fibula. While the artefact was accessioned as a necklace, it might in fact be a waist-band. With so many jaws of different species, the artefact differs markedly from other readily identifiable necklaces and girdles.
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- 2021
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7. Photobody Detection Using Immunofluorescence and Super-Resolution Imaging in Arabidopsis
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Anna Zioutopoulou, Andrew J. Hamilton, Giorgio Perrella, and Eirini Kaiserli
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0106 biological sciences ,0303 health sciences ,medicine.diagnostic_test ,biology ,In situ hybridization ,Compartmentalization (psychology) ,Immunofluorescence ,biology.organism_classification ,01 natural sciences ,Cell biology ,Protein–protein interaction ,03 medical and health sciences ,Immunolabeling ,Arabidopsis ,medicine ,Nuclear localization sequence ,Function (biology) ,030304 developmental biology ,010606 plant biology & botany - Abstract
Light triggers changes in plant nuclear architecture to control differentiation, adaptation, and growth. A series of genetic, molecular, and imaging approaches have revealed that the nucleus forms a hub for photo-induced protein interactions and gene regulatory events. However, the mechanism and function of light-induced nuclear compartmentalization is still unclear. This chapter provides detailed experimental protocols for examining the morphology and potential functional significance of light signaling components that localize in light-induced subnuclear domains, also known as photobodies. We describe how immunolabeling of endogenous proteins and fluorescent in situ hybridization (FISH) could be combined with confocal imaging of fluorescently tagged proteins to assess co-localization in Arabidopsis nuclei. Furthermore, we employ a super-resolution imaging approach to study the morphology of photobodies at unprecedented detail.
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- 2021
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8. Visualizing Mitochondrial Ribosomal RNA and Mitochondrial Protein Synthesis in Human Cell Lines
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Rolando Berlinguer-Palmini, Robert N. Lightowlers, Zofia M.A. Chrzanowska-Lightowlers, Andrew J. Hamilton, Yasmin Proctor-Kent, and Matthew Zorkau
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0303 health sciences ,Mitochondrial DNA ,Chemistry ,030302 biochemistry & molecular biology ,RNA ,Translation (biology) ,In situ hybridization ,Mitochondrion ,Ribosomal RNA ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,Protein biosynthesis ,DNA ,030304 developmental biology - Abstract
Human mitochondria contain their own DNA (mtDNA) that encodes 13 proteins all of which are core subunits of oxidative phosphorylation (OXPHOS) complexes. To form functional complexes, these 13 components need to be correctly assembled with approximately 70 nuclear-encoded subunits that are imported following synthesis in the cytosol. How this complicated coordinated translation and assembly is choreographed is still not clear. Methods are being developed to determine whether all members of a particular complex are translated in close proximity, whether protein synthesis is clustered in submitochondrial factories, whether these align with incoming polypeptides, and if there is evidence for co-translational translation that is regulated and limited by the interaction of the incoming proteins with synthesis of their mtDNA-encoded partners. Two methods are described in this chapter to visualize the distribution of mitochondrial ribosomal RNAs in conjunction with newly synthesized mitochondrial proteins. The first combines RNA Fluorescent In Situ Hybridization (FISH) and super-resolution immunocytochemistry to pinpoint mitochondrial ribosomal RNA. The second localizes nascent translation within the mitochondrial network through non-canonical amino acid labeling, click chemistry and fluorescent microscopy.
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- 2020
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9. Antibody therapy for histoplasmosis
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Joshua D Nosanchuk, Rosely M Zancope-Oliveira, Andrew J Hamilton, and Allan J. Guimaraes
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Histoplasma ,Heat shock protein ,antibody ,fungal pathogenesis ,Histone 2B ,M antigen ,Microbiology ,QR1-502 - Abstract
The endemic human pathogenic fungus Histoplasma capsulatum is a major fungal pathogen with a broad variety of clinical presentations, ranging from mild, focal pulmonary disease to life-threatening systemic infections. Although azoles, such as itraconazole and voriconazole, and amphotericin B have significant activity against H. capsulatum, about 1 in 10 patients hospitalized due to histoplasmosis die. Hence, new approaches for managing disease are being sought. Over the past 10 years, studies have demonstrated that monoclonal antibodies (mAbs) can modify the pathogenesis of histoplasmosis. Disease has been shown to be impacted by mAbs targeting either fungal cell surface proteins or host co-stimulatory molecules. This review will detail our current knowledge regarding the impact of antibody therapy on histoplasmosis.
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- 2012
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10. Four famous suicides in history and lessons learned: A narrative review
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Andrew J. Hamilton
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Psychoanalysis ,biology ,Public Health, Environmental and Occupational Health ,Bipolar mood disorder ,biology.organism_classification ,Mental illness ,medicine.disease ,030227 psychiatry ,SOCRATES ,03 medical and health sciences ,Psychiatry and Mental health ,Cleopatra ,0302 clinical medicine ,medicine ,Narrative review ,030212 general & internal medicine ,Psychology ,Social psychology ,Scientific disciplines - Abstract
History can complement the scientific disciplines in teaching us about the nature of suicide. The death of Socrates, especially as described by Xenophon, suggests fear of the frailties of old age as a motive for suicide. A Platonic view implies heroism and martyrdom. Cleopatra's death and Kurt Cobain's signify the importance of losing when the stakes are high, to the extent that the potential loss is simply too great to live with. Hemingway's death provides strong evidence for a genetic role at play, coupled with various risk factors, most notably mental illness (probably bipolar mood disorder) and setting unrealistic goals.
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- 2016
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11. Conjunctive howeveritis
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Andrew J. Hamilton
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060201 languages & linguistics ,Linguistics and Language ,History ,British English ,06 humanities and the arts ,Adverb ,Language and Linguistics ,language.human_language ,Linguistics ,Conjunction (grammar) ,030507 speech-language pathology & audiology ,03 medical and health sciences ,Fragment (logic) ,0602 languages and literature ,language ,Corpus based ,Linguistic description ,0305 other medical science ,Yet another ,Sentence - Abstract
The word however is an adverb and an adverb alone. The current online Oxford (Oxford English Dictionary Online, n.d.) and Cambridge (Cambridge English Dictionary Online, n.d. a) English dictionaries both have it listed solely as an adverb for British English. At the risk of awakening yet another descriptivist versus prescriptivist war, it must however be acknowledged that however is often used as a conjunction. This can, and frequently does, lead to confusion though, as the reader has to read on before realising that in fact that however was actually being used as a conjunction (or ‘connective’ in modern grammatical parlance). ‘However the cat walked down the street …’ surely has the reader thinking something along the lines of ‘In whatever manner the cat walked down the street …’ But a typical case of what I shall in this article call conjunctive howeveritis would reveal a complete (well, incomplete actually) sentence along the lines of, ‘However the cat walked down the street, even though it rarely ventured from the house.’ Not only are we now left with a sentence fragment, but in such an instance the reader would have to backtrack and subsequently assume the However was in fact being used as a coordinating conjunction. To me this is inefficient and an enemy of lucid writing. The Cambridge English Dictionary raises the warning flag high with the following example (Cambridge English Dictionary Online, n.d. b): Warning:We can't use however as a conjunction instead of but to connect words and phrases:My teacher is very nice but a bit strict.Not:My teacher is very nice however a bit strict.
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- 2016
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12. Abscopal Effect after Radiosurgery for Solitary Brain Metastasis from Non-small Cell Lung Cancer
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Paul Chuba, Jerome Seid, Kyle Verdecchia, and Andrew J Hamilton
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squamous cell carcinoma ,0301 basic medicine ,Oncology ,medicine.medical_specialty ,abscopal effect ,medicine.medical_treatment ,Spontaneous remission ,radiation therapy ,Radiosurgery ,03 medical and health sciences ,0302 clinical medicine ,brain metastases ,Internal medicine ,medicine ,Lung cancer ,radiotherapy ,non-small cell lung cancer ,irradiation ,business.industry ,radiosurgery ,General Engineering ,Cancer ,Abscopal effect ,Immunotherapy ,medicine.disease ,Radiation therapy ,030104 developmental biology ,030220 oncology & carcinogenesis ,Radiation Oncology ,immunotherapy ,Radiology ,business ,Brain metastasis - Abstract
The abscopal effect is a phenomenon relating to the treatment of metastatic cancer in which localized irradiation to a tumor concurrently causes shrinkage of tumors distant from the area of treatment. Localized radiotherapy is thought to cause anti-tumor immunologic responses that lead to regression and remission of cancers distant to the initial location of treatment. We present a 47-year-old male with brain metastasis from non-small cell lung cancer (NSCLC) who went into remission following stereotactic radiosurgery treatment to a brain lesion, in the absence of systemic treatment. We discuss the novelty of this case and its importance to future research on the abscopal effect. Though it is difficult to distinguish the abscopal effect from spontaneous remission of non-targeted cancer, this report sheds insight on the potential for improving treatment for the leading cause of cancer death worldwide.
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- 2018
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13. Human and environmental health risks and benefits associated with use of urban stormwater
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Andrew J. Hamilton, Xiao Huang, David Thomas McCarthy, Sunny C. Jiang, and Keah-Ying Lim
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Pollutant ,geography ,geography.geographical_feature_category ,Resource (biology) ,Ecology ,business.industry ,Environmental resource management ,Stormwater ,Wildlife ,Stormwater harvesting ,Ocean Engineering ,Wetland ,Management, Monitoring, Policy and Law ,Aquatic Science ,Oceanography ,Rainwater harvesting ,Water scarcity ,Environmental health ,business ,Water Science and Technology - Abstract
For stormwater harvesting to achieve its full potential in mitigating water scarcity problems and restoring stream health, it is necessary to evaluate the human and environmental health risks and benefits associated with it. Stormwater harbors large amounts of pollutants and has traditionally been viewed as a leading cause of water-quality degradation of receiving waters. Harvesting stormwater for household use raises questions of human exposure to pollutants, especially human pathogens, which have the potential to cause large-scale disease outbreaks. These issues are compounded by uncertainties relating to the performance of stormwater treatment technologies in pathogen removal. Quantitative microbial risk assessment provides an objective risk estimate based on scientific data and the best assumptions, which can be used to educate and instil confidence in stakeholders of the practice. Although limited, human health risk studies have positively supported the use of minimally treated rainwater and stormwater for some non-potable applications. In addition to the well-known benefit of preserving the stream hydrology and ecology, wetlands used for harvesting stormwater can also provide new habitats for wildlife that benefit environmental health. A fundamental change from viewing stormwater as waste to resource requires the coordinated efforts in research, education, and effective communication. WIREs Water 2015, 2:683–699. doi: 10.1002/wat2.1107 For further resources related to this article, please visit the WIREs website.
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- 2015
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14. Fighting drought with innovation: Melbourne's response to the Millennium Drought in Southeast Australia
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David L. Feldman, Jean-Daniel Saphores, Andrew J. Hamilton, Kein Gan, Stanley B. Grant, Meenakshi Arora, and Kathleen G Low
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Demand management ,Ecology ,business.industry ,Natural resource economics ,Water supply ,Ocean Engineering ,Management, Monitoring, Policy and Law ,Aquatic Science ,Water pricing ,Oceanography ,Irrigation district ,Water trading ,Water resources ,Water conservation ,Clean Water and Sanitation ,Agriculture ,Environmental protection ,Environmental science ,business ,Water Science and Technology - Abstract
The Millennium Drought in Southeast Australia forced greater Melbourne, a city of 4.3 million people, to find innovative ways of increasing water supply and decreasing water demand. This article explores how water managers in Melbourne reacted to the crisis and evaluates the short- and long-term impacts of their decisions. Reduced water demand occurred primarily through residential and industrial water conservation programs, restrictions, together with emergency reductions in the environmental release of water to streams. The city also experimented with using recycled water, in place of surface water, to support agriculture in the Werribee Irrigation District. Water pricing was not strengthened during the drought, and thus not regarded as a drought demand management tool, primarily because Melbourne water companies lacked independent price-setting powers. Today, five years after the end of the Millennium Drought, gains in water conservation appear to be holding steady, but recycled water for irrigation has declined for various reasons. We contend that the Millennium Drought provided Melbourne with the opportunity to develop and implement a more integrated approach to water management. Many of the innovations it forged (e.g., distributed harvesting and use of stormwater) will continue to enhance the city’s resilience to drought and reduce its vulnerability to climate variability for years to come. Nevertheless, a challenge going forward is how to sustain these achievements in light of anticipated population growth and continued climatic change. This challenge—coupled with Melbourne’s successes—hold important lessons for water-stressed cities around the world. © 2015 Wiley Periodicals, Inc. How to cite this article
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- 2015
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15. Investigation of feeding preferences of GPS monitored sheep in a binary choice experimental design under conditions of spatial uncertainty
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Edward K. Waters, M. Raeside, Andrew J. Hamilton, Allison Kealy, Kurt K. Benke, F. Sheth, and A. Haznur Rabian
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0106 biological sciences ,Atmospheric Science ,Calibration (statistics) ,business.industry ,Geography, Planning and Development ,Binary number ,02 engineering and technology ,Satellite tracking ,010603 evolutionary biology ,01 natural sciences ,Binomial distribution ,General Energy ,Geography ,020204 information systems ,Grazing ,0202 electrical engineering, electronic engineering, information engineering ,Global Positioning System ,Decision boundary ,business ,Null hypothesis ,Remote sensing - Abstract
A methodology is investigated for assessment of feeding preferences of grazing sheep where satellite tracking is carried out using GPS collar units. Sheep grazing preferences were analysed by a statistically based approach under constraints of spatial error in the GPS tracking data. The statistical significance of grazing locations was determined by testing a null hypothesis on animal locations in two adjacent pastures using the normal approximation to the binomial distribution for proportions. The analysis also included calibration and compensation for the precision of the GPS receiver, which produced an uncertain decision boundary between the paddocks. It was concluded that the approach was effective in dealing with GPS spatial errors and in comparing the feeding preferences of sheep.
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- 2015
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16. A transgene with repeated DNA causes high frequency, post-transcriptional suppression of ACC-oxidase gene expression in tomato
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Andrew J, Hamilton, Stephen, Brown, Han, Yuanhai, Masakatsu, Ishizuka, Alex, Lowe, Angel-Gabriel Alpuche, Solis, and Don, Grierson
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Gene silencing with sense genes is an important method for down-regulating the expression of endogenous plant genes, but the frequency of silencing is unpredictable. Fifteen per cent of tomato plants transformed with a 35S-ACC-oxidase ( ACO 1) sense gene had reduced ACC-oxidase activity. However, 96% of plants transformed with an ACC-oxidase sense gene, containing two additional upstream inverted copies of its 5' untranslated region, exhibited reduced ACC-oxidase activity compared to wild-type plants. In the three plants chosen for analysis, there were substantially reduced amounts of both endogenous and transgenic ACO RNA, indicating that this was an example of co-suppression. Ribonuclease protection assays using probes spanning intron-exon borders showed that the reduced accumulation of endogenous ACO mRNA occurred post-transcriptionally since the abundance of unprocessed transcripts was not affected. The ACO1 transgene with the repeated 5'UTR also strongly inhibited the accumulation of RNA from the related ACO 2 gene in flowers, although there is little homology between the 5'UTRs of ACO 1 and ACO 2. These results indicate that although repeated DNA in a transgene greatly enhances the probability of gene silencing of an endogenous gene, it also involves generation of a trans -acting silencing signal produced, at least partly, from sequences external to the repeat.
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- 2018
17. Practical yield loss models for infestation of cocoa with cocoa pod borer moth, Conopomorpha cramerella (Snellen)
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Richard T. Roush, Isabel Valenzuela, Andrew J. Hamilton, and Hussin Bin Purung
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biology ,medicine.disease_cause ,Explained variation ,biology.organism_classification ,Toxicology ,Point of delivery ,Agronomy ,Dry weight ,Infestation ,Linear regression ,medicine ,PEST analysis ,Akaike information criterion ,Agronomy and Crop Science ,Conopomorpha cramerella - Abstract
The cocoa pod borer, Conopomorpha cramerella (Snellen) (Gracillariidae: Gracillariinae), is an important pest of cocoa in Southeast Asia and Oceania, with devastating effects on yields. Using data on cocoa pod borer (CPB) infestation and cocoa yield from mixed-variety plantations in South Sulawesi, Indonesia, we developed models for estimating yield and yield loss under CPB attack. For six yield variables, two types of models were constructed: non-linear regressions based upon the presence or absence of infestation of pods (PI model), and multiple linear regressions for a four-point graded system of infestation severity (IS model). The IS models performed markedly better than PI models, in terms of percentage of variance explained, for all variables, also supported by Corrected Akaike Information Criterion values. But the explanatory power of the best-fit models was still poor for some variables. The fits were strongest for arguably the two most important variables in the industry, dry weight/pod and pod value (the number of pods required to achieve 1 kg of dry cocoa), with 62% and 69% of the variance accounted for, respectively. Validation of the dry weight/pod and pod value models against an independent dataset from South Sulawesi indicated that the models slightly under-estimated both yield indicators that increase concomitantly with the degree of yield loss. We propose the IS models, particularly that for pod value, as useful tools for industry, and argue that they will have broad utility given that they are based on mixedcultivar plantations. Not only are these the first CPB yield-loss models to be based on commercial mixed plantings, they also represent the first attempt to employ a gradation of infestation severity based on simple visual assessment, which proved to be an important advance.
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- 2014
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18. Field comparison and crop production modeling of sweet corn and silage maize (Zea mays L.) with treated urban wastewater and freshwater
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Hoi-Fei Mok, Kithsiri B. Dassanayake, Andrew J. Hamilton, and Graham Hepworth
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Soil health ,Irrigation ,Topsoil ,Crop yield ,Soil Science ,engineering.material ,Agronomy ,Wastewater ,engineering ,Environmental science ,Sewage treatment ,Fertilizer ,Agronomy and Crop Science ,Surface irrigation ,Water Science and Technology - Abstract
In Australia, interest in wastewater reuse has grown. While wastewater can potentially offer a nutrient advantage over conventional irrigation, crop yield increases may be offset by effects of high salinity. Effects of wastewater irrigation on crop production and soil health were investigated in two ways: a field experiment addressing short-term effects and modeling longer-term impacts. The field experiment was established at the Shepparton Wastewater Treatment Plant in Shepparton, Victoria, to compare effects of wastewater irrigation to conventional irrigation. Silage maize and sweet corn (Zea mays L.) were grown over the summer of 2012–2013 under the following flood irrigation treatments: wastewater and freshwater with and without fertilizer. Both harvests produced yields and qualities comparable to commercial farm standards, and no significant differences were found between water types. Maize production with long-term wastewater irrigation at various salinities was modeled, and no significant yield losses were observed after 50 years of simulated irrigation. Topsoil electroconductivity doubled after the field trial and simulation results predicted significant soil salt accumulation by factor of 2. Mean wastewater sodium absorption ratio of 4.52 and electroconductivity of 1.52 dS/m indicate potential for sodicity-related soil problems for long-term irrigation. Management of soil health may be necessary.
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- 2014
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19. Waterbird use of different treatment stages in waste-stabilisation pond systems
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Andrew J. Hamilton, Regan Barratt, Sabine Kasel, Christopher G. Murray, and Erin Szantyr
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0106 biological sciences ,geography ,geography.geographical_feature_category ,biology ,business.industry ,Ecology ,Sewage ,Wetland ,04 agricultural and veterinary sciences ,biology.organism_classification ,01 natural sciences ,010605 ornithology ,040103 agronomy & agriculture ,Waterfowl ,0401 agriculture, forestry, and fisheries ,River management ,Animal Science and Zoology ,business ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
The significance of waste-stabilisation ponds (WSPs) to waterbirds has been well documented, but WSP differ depending on their place and purpose in the sewage-treatment system, and there is little ...
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- 2014
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20. Exposure Factors for Wastewater-Irrigated Asian Vegetables and a Probabilistic Rotavirus Disease Burden Model for Their Consumption
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Andrew J. Hamilton and Hoi-Fei Mok
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Irrigation ,business.industry ,Environmental exposure ,Biology ,Toxicology ,Agronomy ,Wastewater ,Agriculture ,Physiology (medical) ,Brassica rapa ,Food processing ,Safety, Risk, Reliability and Quality ,business ,Surface irrigation ,Disease burden - Abstract
Many farmers in water-scarce regions of developing countries use wastewater to irrigate vegetables and other agricultural crops, a practice that may expand with climate change. There are a number of health risks associated with wastewater irrigation for human food crops, particularly with surface irrigation techniques common in the developing world. The World Health Organization (WHO) recommends using quantitative microbial risk assessment (QMRA) to determine if the irrigation scheme meets health standards. However, only a few vegetables have been studied for wastewater risk and little information is known about the disease burden of wastewater-irrigated vegetable consumption in China. To bridge this knowledge gap, an experiment was conducted to determine volume of water left on Asian vegetables and lettuce after irrigation. One hundred samples each of Chinese chard (Brassica rapa var. chinensis), Chinese broccoli (Brassica oleracea var. alboglabra), Chinese flowering cabbage (Brassica rapa var. parachinensis), and lettuce (Lactuca sativa) were harvested after overhead sprinkler irrigation. Chinese broccoli and flowering cabbage were found to capture the most water and lettuce the least. QMRAs were then constructed to estimate rotavirus disease burden from consumption of wastewater-irrigated Asian vegetables in Beijing. Results indicate that estimated risks from these reuse scenarios exceed WHO guideline thresholds for acceptable disease burden for wastewater use, signifying that reduction of pathogen concentration or stricter risk management is necessary for safe reuse. Considering the widespread practice of wastewater irrigation for food production, particularly in developing countries, incorporation of water retention factors in QMRAs can reduce uncertainty regarding health risks for consumers worldwide.
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- 2014
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21. Comparison of Four Bootstrap-Based Interval Estimators of Species Occupancy and Detection Probabilities
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Geoffrey W. Heard, Graham Hepworth, Andrew J. Hamilton, Andrew P. Robinson, and Natalie Karavarsamis
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Statistics and Probability ,Percentile ,Occupancy ,Overdispersion ,Statistics ,Sampling (statistics) ,Estimator ,Interval (mathematics) ,Statistics, Probability and Uncertainty ,Confidence interval ,Statistical power ,Mathematics - Abstract
Summary: Site occupancy, as estimated by the probability of presence, is used for monitoring species populations. However, the detection of species at individual sites is often subject to errors. In order to accurately estimate occupancy we must simultaneously account for imperfect detectability by estimating the probability of detection. The problem with estimating occupancy arises from not knowing whether a nondetection occurred at an occupied site due to imperfect detectability (sampling zeros), or the nondetection resulting from an unoccupied site (fixed zeros). We evaluated the performance of the basic, normal approximation, studentised and percentile methods for approximating confidence limits for occupancy and detection of species. Using coverage and average interval width, we demonstrated that the studentised estimator was generally superior to the others, except when a small sample of sites are selected. Under this circumstance and when calculating limits for detection, no estimator produced reliable results. The experimental factors we considered include: (i) number of sites; (ii) number of survey occasions; (iii) probabilities of presence (occupancy) and detection; and (iv) overdispersion in the capture matrix. Similar conclusions were reached both for the simulated studies and a case study. Overall, estimation near the boundaries of the probability of occupancy and detectability was difficult. © 2013 Australian Statistical Publishing Association Inc. Published by Wiley Publishing Asia Pty Ltd.
- Published
- 2013
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22. Pathogen reduction requirements for direct potable reuse in Antarctica: Evaluating human health risks in small communities
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Stephen Gray, M Packer, Andrew J. Hamilton, Peter J. Scales, S. Fiona Barker, and Ian Snape
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Environmental Engineering ,Population ,Antarctic Regions ,Sewage ,Water supply ,Wastewater ,medicine.disease_cause ,Communicable Diseases ,Risk Assessment ,Water Purification ,Water Supply ,Environmental health ,medicine ,Humans ,Environmental Chemistry ,Recycling ,education ,Waste Management and Disposal ,Disease burden ,education.field_of_study ,business.industry ,Giardia ,Campylobacter ,Norovirus ,Environmental engineering ,Outbreak ,Models, Theoretical ,Pollution ,Environmental science ,Sewage treatment ,Water Microbiology ,business ,Risk assessment - Abstract
Small, remote communities often have limited access to energy and water. Direct potable reuse of treated wastewater has recently gained attention as a potential solution for water-stressed regions, but requires further evaluation specific to small communities. The required pathogen reduction needed for safe implementation of direct potable reuse of treated sewage is an important consideration but these are typically quantified for larger communities and cities. A quantitative microbial risk assessment (QMRA) was conducted, using norovirus, giardia and Campylobacter as reference pathogens, to determine the level of treatment required to meet the tolerable annual disease burden of 10(-6) DALYs per person per year, using Davis Station in Antarctica as an example of a small remote community. Two scenarios were compared: published municipal sewage pathogen loads and estimated pathogen loads during a gastroenteritis outbreak. For the municipal sewage scenario, estimated required log10 reductions were 6.9, 8.0 and 7.4 for norovirus, giardia and Campylobacter respectively, while for the outbreak scenario the values were 12.1, 10.4 and 12.3 (95th percentiles). Pathogen concentrations are higher under outbreak conditions as a function of the relatively greater degree of contact between community members in a small population, compared with interactions in a large city, resulting in a higher proportion of the population being at risk of infection and illness. While the estimates of outbreak conditions may overestimate sewage concentration to some degree, the results suggest that additional treatment barriers would be required to achieve regulatory compliance for safe drinking water in small communities.
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- 2013
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23. Waterbird use of artificial wetlands in an Australian urban landscape
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Graham Hepworth, Andrew J. Hamilton, Sabine Kasel, Christopher G. Murray, and Richard H. Loyn
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Shore ,geography ,geography.geographical_feature_category ,biology ,Ecology ,Community structure ,Wetland ,Aquatic Science ,biology.organism_classification ,Zooplankton ,Habitat ,Abundance (ecology) ,Guild ,Waterfowl - Abstract
With the loss of natural wetlands, artificial wetlands are becoming increasingly important as habitat for waterbirds. We investigated the relationships between waterbirds and various biophysical parameters on artificial wetlands in an Australian urban valley. The densities (birds per hectare) of several species were correlated (mostly positively) with wetland area, and correlations were observed between certain species and other physical and water chemistry variables. Waterbird community structure, based on both abundance (birds per wetland) and density data, was most consistently positively correlated with the relative amount of wetland perimeter that was vegetated, surface area, distance to nearest wetland, public accessibility and shoreline irregularity. We also compared the relative use of the two types of urban wetlands, namely urban lakes and stormwater treatment wetlands, and found for both abundance and density that the number of individuals and species did not vary significantly between wetland types but that significant differences were observed for particular species and feeding guilds, with no species or guild being more abundant or found in greater density on an urban lake than a stormwater treatment wetland. Designing wetlands to provide a diversity of habitat will benefit most species.
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- 2013
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24. In situ imaging of mitochondrial translation shows weak correlation with nucleoid DNA intensity and no suppression during mitosis
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Andrew J. Hamilton, Sarah El-Messeiry, Emmanouela Stamatidou, and Christopher Estell
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0301 basic medicine ,Mitochondrial DNA ,Mitochondrial translation ,Cytoplasmic translation ,Cell ,Translation (biology) ,Cell Biology ,Biology ,Mitochondrion ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,medicine.anatomical_structure ,medicine ,Nucleoid ,Mitosis - Abstract
Although mitochondrial translation produces only 13 proteins, we show here how this process can be visualised and detected in situ by fluorescence microscopy with a simple, rapid and inexpensive procedure using non-canonical amino acid labelling and click chemistry. This allows visualisation of the translational output in different mitochondria within a cell, their position within that cell and a comparison of mitochondrial translation between cells. The most highly translationally active mitochondria were closest to the nucleus but were also found at the distal end of long cellular projections. There were substantial differences in translation between adjacent mitochondria and this did not readily correlate with apparent mitochondrial genome content. Mitochondrial translation was unchanged during mitosis when cytoplasmic translation was suppressed. This method will serve both fundamental cell biology and clinically orientated studies, in which mitochondrial function is a key parameter.
- Published
- 2017
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25. Was monochloramine responsible for widespread lettuce crop failures at a major recycled water irrigation scheme?
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Graham Hepworth, Andrew J. Hamilton, S. F. Barker, J. Blackbeard, and Robert Faggian
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Crop ,Salinity ,Irrigation ,Chlorosis ,Agronomy ,Water irrigation ,Wilting ,Greenhouse ,Environmental science ,Filtration and Separation ,Iceberg lettuce ,Water Science and Technology - Abstract
In 2008, vegetable growers observed stunted lettuce plants showing signs of chlorosis and wilting. It was suspected that monochloramine in the recycled water used for irrigation, in combination with extreme environmental conditions (high irrigation water salinity and extreme heat), was responsible for these crop failures. A series of glasshouse studies was conducted to evaluate the impact of monochloramine concentration alone on iceberg lettuce seedlings, as well as in combination with high salinity and hot ambient temperatures. Monochloramine concentrations up to 9 and 15 mg L−1 Cl2 for continuous and initial irrigation only, respectively, did not affect the weight of iceberg lettuce heads (p > 0.05), while the combination of monochloramine (4–5 mg L−1 Cl2) and salinity (3,500 μS cm−1) did not significantly affect harvest measurements (p > 0.05). We therefore conclude that it is unlikely that monochloramine was responsible for the observed crop failures.
- Published
- 2013
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26. Do Not 'Let Them Eat Cake': Correlation of Food-Consumption Patterns among Rural Primary School Children from Welfare and Non-Welfare Households
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Kaye Ervin, Andrew J. Hamilton, Erin Soutter, Nicole Dalle Nogare, Daniel Terry, and Renata Spiller
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0301 basic medicine ,Male ,Parents ,Victoria ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,lcsh:Medicine ,Context (language use) ,drinking ,socioeconomic factors ,Social class ,Article ,Beverages ,03 medical and health sciences ,0302 clinical medicine ,Residence Characteristics ,Environmental health ,Food choice ,Vegetables ,medicine ,Animals ,Humans ,030212 general & internal medicine ,Child ,Socioeconomic status ,media_common ,Consumption (economics) ,eating behaviour ,030109 nutrition & dietetics ,food ,lcsh:R ,digestive, oral, and skin physiology ,Public Health, Environmental and Occupational Health ,Feeding Behavior ,medicine.disease ,Obesity ,Educational attainment ,healthy eating ,Social Class ,Fruit ,Income ,Female ,Snacks ,Welfare ,Social psychology - Abstract
Physical and financial access impacts food choice and consumption, while educational attainment, employment, income, gender, and socioeconomic status are also influential. Within this context, the aim of the paper is to examine the association between various foods consumed and eating patterns of children between low and higher income households. A paper-based survey was completed by parents/carers of children in 41 primary schools in rural and regional areas of Victoria. Data collected included demographics and the consumption of fruit, vegetable, and other foods including drinks. Ordinal data were analysed using Spearman's rank-order correlation. The main findings were that children who consumed more fruit and vegetables tended to have a higher intake of healthy drinks (plain milk and water) as well as a lower intake of unhealthy snacks and drinks (sugar sweetened drinks). Those who perceived that fruit and vegetables cost too much reported greater consumption of unhealthy snacks and sugar-sweetened beverages, which was more prominent in low-income households. Changing food consumption behaviours requires a complex systems-based approach that addresses more than just individual issues variables. A participatory approach that works with local communities and seeks to build an understanding of unique challenges within sub-groups has potential for embedding long-lasting and meaningful change in eating behaviours.
- Published
- 2016
27. Identification of Preferential Paths of Fossil Carbon within Water Resource Recovery Facilities via Radiocarbon Analysis
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Linda Y. Tseng, Reza Sobhani, John Southon, Andrew J. Hamilton, Xiaying Zhang, Diego Rosso, Xiaomei Xu, Alice K. Robinson, and Michael K. Stenstrom
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Secondary treatment ,Greenhouse Effect ,010504 meteorology & atmospheric sciences ,Climate Change ,chemistry.chemical_element ,010501 environmental sciences ,01 natural sciences ,chemistry.chemical_compound ,Dissolved organic carbon ,Environmental Chemistry ,Greenhouse effect ,0105 earth and related environmental sciences ,Resource recovery ,Waste management ,Sewage ,Fossils ,Environmental engineering ,General Chemistry ,Carbon Dioxide ,Carbon ,chemistry ,Wastewater ,Greenhouse gas ,Carbon dioxide ,Water Resources ,Environmental science - Abstract
The Intergovernmental Panel on Climate Change (IPCC) reported that all carbon dioxide (CO2) emissions generated by water resource recovery facilities (WRRFs) during treatment are modern, based on available literature. Therefore, such emissions were omitted from IPCC’s greenhouse gas (GHG) accounting procedures. However, a fraction of wastewater’s carbon is fossil in origin. We hypothesized that since the fossil carbon entering municipal WRRFs is mostly from soaps and detergents as dissolved organic matter, its fate can be selectively determined during the universally applied separation treatment processes. Analyzing radiocarbon at different treatment points within municipal WRRFs, we verified that the fossil content could amount to 28% in primary influent and showed varying distribution leaving different unit operations. We recorded the highest proportion of fossil carbon leaving the secondary treatment as off-gas and as solid sludge (averaged 2.08 kg fossil-CO2-emission-potential m–3 wastewater treated)....
- Published
- 2016
28. What can a database compiled over 22 years tell us about the use of different types of wetlands by waterfowl in south-eastern Australian summers?
- Author
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Kasey Stamation, Andrew J. Hamilton, Richard H. Loyn, Sabine Kasel, Christopher G. Murray, and Graham Hepworth
- Subjects
0106 biological sciences ,geography ,geography.geographical_feature_category ,biology ,Database ,Ecology ,Biodiversity ,food and beverages ,Wetland ,biology.organism_classification ,computer.software_genre ,010603 evolutionary biology ,01 natural sciences ,010605 ornithology ,Habitat ,Abundance (ecology) ,Waterfowl ,Animal Science and Zoology ,Wildlife management ,Conservation biology ,computer ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,Global biodiversity - Abstract
Understanding the roles of different types of natural and artificial wetlands in providing habitat for waterbirds is crucial to active interventions to conserve wetland biodiversity. This study made use of a large database compiled over 22 years from the ‘Summer Waterfowl Count’ to determine the relative use of five wetland types by 18 species of waterfowl in Victoria, south-eastern Australia. The abundance of 14 species and density of 15 differed significantly (P
- Published
- 2012
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29. Microbial quality assessment of household greywater
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Andrew J. Hamilton, Joanne Elizabeth O'Toole, Manori Geetanjali Malawaraarachchi, Karin Leder, Martha Irvine Sinclair, and S. Fiona Barker
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Diarrhea ,Rotavirus ,Environmental Engineering ,Gastrointestinal Diseases ,Vomiting ,viruses ,Biology ,medicine.disease_cause ,Greywater ,Risk Assessment ,Waste Disposal, Fluid ,Virus ,Microbiology ,Feces ,fluids and secretions ,Risk Factors ,Water Supply ,Water Quality ,Escherichia coli ,medicine ,Humans ,Waste Management and Disposal ,Enterovirus ,Water Science and Technology ,Civil and Structural Engineering ,Reverse Transcriptase Polymerase Chain Reaction ,Quality assessment ,Ecological Modeling ,Norovirus ,Australia ,virus diseases ,Pollution ,Monitoring program ,Gastrointestinal Tract ,Water Microbiology - Abstract
A monitoring program was undertaken to assess the microbial quality of greywater collected from 93 typical households in Melbourne, Australia. A total of 185 samples, comprising 75 washing machine wash, 74 washing machine rinse and 36 bathroom samples were analysed for the faecal indicator Escherichia coli. Of these, 104 were also analysed for genetic markers of pathogenic E coli and 111 for norovirus (genogroups GI and GII), enterovirus and rotavirus using RT-PCR. Enteric viruses were detected in 20 out of the 111 (18%) samples comprising 16 washing machine wash water and 4 bathroom samples. Eight (7%) samples were positive for enterovirus, twelve (11%) for norovirus genogroup GI, one (1%) for norovirus genogroup GII and another (1%) for rotavirus. Two washing machine samples contained more than one virus. Typical pathogenic E. coli were detected in 3 out of 104 (3%) samples and atypical enteropathogenic E. coli in 11 (11%) of samples. Levels of indicator E. coli were highly variable and the presence of E. coli was not associated with the presence of human enteric viruses in greywater. There was also little correlation between reported gastrointestinal illness in households and detection of pathogens in greywater.
- Published
- 2012
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30. Taking the 'Waste' Out of 'Wastewater' for Human Water Security and Ecosystem Sustainability
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Sunny C. Jiang, Ivan Marusic, Andrew J. Hamilton, Brett F. Sanders, Rebekah Ruth Brown, Perran L. M. Cook, Ana Deletic, Diego Rosso, Lisa A. Levin, Jean-Daniel Saphores, William J. Cooper, Stanley B. Grant, Michael J. Stewardson, Tim D. Fletcher, David L. Feldman, and Richard F. Ambrose
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Conservation of Natural Resources ,Natural resource economics ,Water supply ,Sewage ,Fresh Water ,Waste Disposal, Fluid ,Water Purification ,Water Supply ,Water Quality ,Humans ,Recycling ,Developing Countries ,Ecosystem ,Ecosystem health ,Multidisciplinary ,business.industry ,Developed Countries ,Drinking Water ,Water Pollution ,Agriculture ,Biodiversity ,Water security ,Wastewater ,Sustainability ,Water quality ,business ,Waste disposal - Abstract
Humans create vast quantities of wastewater through inefficiencies and poor management of water systems. The wasting of water poses sustainability challenges, depletes energy reserves, and undermines human water security and ecosystem health. Here we review emerging approaches for reusing wastewater and minimizing its generation. These complementary options make the most of scarce freshwater resources, serve the varying water needs of both developed and developing countries, and confer a variety of environmental benefits. Their widespread adoption will require changing how freshwater is sourced, used, managed, and priced.
- Published
- 2012
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31. REVIEW: Perspectives on wastewater treatment wetlands and waterbird conservation
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Andrew J. Hamilton and Christopher G. Murray
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Resource (biology) ,Geography ,geography.geographical_feature_category ,Ecology ,Sanitation ,Wastewater ,Stabilization pond ,Wetland conservation ,Sewage treatment ,Wetland ,Environmental planning ,Wildlife conservation - Abstract
Summary 1. With the global loss of natural wetlands, waterbirds have become increasingly dependent on alternative and artificial habitats, but the use of such wetlands by waterbirds is typically opportunistic and little consideration has been given to the potential implications for water treatment or waterbird conservation objectives. 2. Wastewater treatment wetlands are currently of critical importance for certain waterbird species in some parts of the world, and we illustrate this with an example from south-eastern Australia. Furthermore, we argue that their significance is likely to increase as they offer the most realistic means of treating wastewater in developing countries, where the demand for improved sanitation to lift people out of poverty is intense. 3. There is little scientific evidence to guide the construction of wastewater treatment wetlands with waterbird conservation in mind. 4. The use of wastewater by waterbirds poses health risks for both birds and humans and these risks must be better understood. 5. Synthesis and applications. Wastewater treatment wetlands are not a substitute for natural wetlands and reliance upon them should not compromise wetland conservation efforts. Nonetheless, they are a potentially valuable resource for waterbirds, and research should be directed towards deepening our understanding of their global distribution; food-web dynamics; methods of deterring or excluding birds when bird or human health may be compromised; the effects of wastewater contaminants and pathogens on birds; and the role of waterbirds in human disease transmission.
- Published
- 2010
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32. Cocoa Pod Borer (Conopomorpha cramerella Snellen) in Papua New Guinea: Biosecurity Models for New Ireland and the Autonomous Region of Bougainville
- Author
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Edward K. Waters, Andrew J. Hamilton, and Jian D. L. Yen
- Subjects
Employment ,Biosecurity ,Introduced species ,medicine.disease_cause ,Models, Biological ,law.invention ,Papua New Guinea ,law ,Physiology (medical) ,Infestation ,Quarantine ,medicine ,Animals ,Safety, Risk, Reliability and Quality ,Conopomorpha cramerella ,Cacao ,Geography ,biology ,Agroforestry ,Ecology ,business.industry ,Sampling (statistics) ,Agriculture ,biology.organism_classification ,Lepidoptera ,Biological dispersal ,business - Abstract
Cocoa Pod Borer (Conopomorpha cramerella Snellen) (CPB) is an important pest of cocoa. Following its emergence as a pest in East New Britain, Papua New Guinea, in 2006, it was considered relevant to assess its potential spread to other cocoa growing regions. Its likeli- hood of introduction to the islands of Bougainville and New Ireland from East New Britain Province, Papua New Guinea, was modeled using Monte Carlo simulation. This dispersal model was based around different scenarios, identifying trends rather than explicitly attempt- ing to encapsulate true values. The model suggested that CPB is far more likely to establish on New Ireland than on Bougainville. More important, incertitude resulting from incomplete knowledge of the amount and frequency of cocoa transported between islands had a signifi- cant effect on model outputs. Quarantine and agriculture officials will be able to refine these parameter values, and then use the relevant scenarios from those presented here as a guide to develop quarantine procedures. In addition, a contingency model was employed to esti- mate the optimal sampling effort to use following an incursion of CPB into Bougainville or New Ireland and the seemingly successful implementation of an initial eradication program. The model suggests that at a 1% infestation level, sampling should continue for 2.5-2.7 years (90% CI) after claiming eradication, and this estimate changed little for higher infestation levels. Through modeling variations in sampling intensity, the model also suggested that determining the full spread of CPB is more important than increased sampling within one region.
- Published
- 2010
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33. Affluent effluent: growing vegetables with wastewater in Melbourne, Australia—a wealthy but bone-dry city
- Author
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Fiona Barker-Reid, Andrew J. Hamilton, and Grant A. Harper
- Subjects
Irrigation ,business.industry ,Geography, Planning and Development ,Greywater ,Agricultural economics ,Reclaimed water ,Water scarcity ,Geography ,Wastewater ,Agriculture ,Management of Technology and Innovation ,Urban agriculture ,Water resource management ,business ,Effluent ,Water Science and Technology ,Food Science - Abstract
Water scarcity in Australia has become a significant challenge for all water users and water reuse is now a critical component of Melbourne’s response to this water crisis, particularly for food production. While most vegetable production occurs in a large-scale commercial environment, there is a significant proportion produced in backyards. With the introduction of severe water restrictions, commercial vegetable production now relies heavily on high quality Class A reclaimed water, while households have turned to the use of greywater. While there are many benefits of wastewater reuse, there are also many potential risks to plant, environmental and human health. A quantitative microbial risk assessment of the two systems was conducted to evaluate the human health risks associated with both large-scale and backyard reuse of water for vegetable irrigation. This preliminary model suggests that for irrigation with typical greywater, the annual infection probability for enteric viruses is >10−4, even after a two week period of no irrigation with greywater. The human annual enteric virus risk from Class A reclaimed water was much lower.
- Published
- 2009
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34. Validation of Fixed Sample Size Plans for Monitoring Lepidopteran Pests of Brassica oleracea Crops in North Korea
- Author
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W. S. Pak, H. J. Kim, Edward K. Waters, Michael J. Furlong, and Andrew J. Hamilton
- Subjects
Integrated pest management ,Ecology ,Economic threshold ,Plutella ,Pieris rapae ,General Medicine ,Biology ,biology.organism_classification ,Population density ,Crop ,Agronomy ,Sample size determination ,Insect Science ,Statistics ,Brassica oleracea - Abstract
The combined action of two lepidoteran pests, Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae), causes significant yield losses in cabbage (Brassica oleracea variety capitata) crops in the Democratic People's Republic of Korea. Integrated pest management (IPM) strategies for these cropping systems are in their infancy, and sampling plans have not yet been developed. We used statistical resampling to assess the performance of fixed sample size plans (ranging from 10 to 50 plants). First, the precision (D = SE/mean) of the plans in estimating the population mean was assessed. There was substantial variation in achieved D for all sample sizes, and sample sizes of at least 20 and 45 plants were required to achieve the acceptable precision level of D ≤ 0.3 at least 50 and 75% of the time, respectively. Second, the performance of the plans in classifying the population density relative to an economic threshold (ET) was assessed. To account for the different damage potentials of the two species the ETs were defined in terms of standard insects (SIs), where 1 SI = 1 P. rapae = 5 P. xylostella larvae. The plans were implemented using different economic thresholds (ETs) for the three growth stages of the crop: precupping (1 SI/plant), cupping (0.5 SI/plant), and heading (4 SI/plant). Improvement in the classification certainty with increasing sample sizes could be seen through the increasing steepness of operating characteristic curves. Rather than prescribe a particular plan, we suggest that the results of these analyses be used to inform practitioners of the relative merits of the different sample sizes.
- Published
- 2009
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35. Partial purification and characterization of a 235000Mr extracellular proteinase from Trichophyton rubrum
- Author
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R. J. Hay, Imelda Lambkin, and Andrew J. Hamilton
- Subjects
chemistry.chemical_classification ,Metalloproteinase ,biology ,Isoelectric focusing ,Dermatology ,General Medicine ,Trichophyton rubrum ,biology.organism_classification ,Infectious Diseases ,Enzyme ,chemistry ,Biochemistry ,Keratin ,Extracellular ,biology.protein ,Serine Proteinase Inhibitors ,Elastin - Abstract
Summary. An extracellular proteinase has been partially purified from culture filtrates of Trichophyton rubrum by ultrafiltration, isoelectric focusing and gel filtration chromatography. The enzyme has a non-reduced molecular weight of 235000 by substrate SDS-PAGE. It has a pH optimum of 8.5 using azocasein and azoalbumin as substrates and a pI of 3.6-3.8. The metalloproteinase inhibitors EDTA and 1,10-phenanthroline, together with the chymotrypsin inhibitor chymostatin, strongly inhibited its activity. The serine proteinase inhibitors phenylmethanesulphonyl fluoride and diisopropylfluorophosphate showed weak inhibitory activity. The proteinase exhibited broad substrate activity against azocoll, azoalbumin, azocasein, laminin and fibronectin. It exhibited weak activity against elastin and keratin. Observations on the occurrence of this proteinase together with previously described lower molecular weight proteinases suggests that the former is the first to appear in minimal medium cultures. Freeze/thaw cycling of the partially purified 235000Mr proteinase was found to generate low molecular weight proteinases, particularly at 53000, 27000 and 25000Mr, indicating that the latter may originate from the larger molecule. Zusammenfassung. Aus Kulturfiltraten von Trichophyton rubrum wurde durch Ultrafiltration, isoelektrische Fokussierung und Gelfiltrationschromatographie eine extrazellulare Proteinase partiell gereinigt. Das Enzym hat nicht reduziert in der Substrat-SDS-PAGE ein Molekulargewicht von 235000. Bei Verwendung von Azocasein und Azoalbumin wurde ein pH-Optimum von 8,5 bestimmt; der pI liegt bei 3.6-3.8. Die Enzymaktivitat wurde durch die Metalloproteinase-Hemmer EDTA und 1,10-Phenanthrolin zusammen mit dem Chymotrypsin-Hemmer Chymostatin stark gehemmt. Die Serinproteinasen-Hemmer Phenylmethansulfonylfluorid und Diisopropylfluorphosphat zeigten nur schwache Hemmwirkung. Die Proteinase zeigte breite Substrataktivitat gegen Azocoll, Azoalbumin, Azocasein, Laminin und Fibronectin; sie zeigte schwache Aktivitat gegen Elastin und Keratin. Im Vergleich mit fruher beschriebenen niedrigmolekular-gewichtigen Proteinasen scheint das hier vorgestellte Enzym in Minimalmedium-Kulturen fruher aufzutreten. Wiederholtes Frieren-Auftauen der partiell gereinigten 235000Mr-Proteinase fuhrte zum Auftreten niedrigmolekulargewichtiger Proteinasen insbesondere von 53000, 27000 und 25000Mr, was darauf hindeutet, das die letzteren vom groseren Molekul abgespalten werden.
- Published
- 2009
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36. Immunogold Electron Microscopical Detection of Tubulin and Actin within Mycelial Phase Histoplasma capsulatum capsulatum and H. capsulatum duboisii Elektronenmikroskopische Immunogold-Darstellung von Tubulin und Actin an der Myzelform von Histoplasma caps
- Author
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Andrew J. Hamilton, Roderick J. Hay, and Bartholomew Ma
- Subjects
Hypha ,medicine.drug_class ,Dermatology ,General Medicine ,Immunogold labelling ,Biology ,Monoclonal antibody ,biology.organism_classification ,Histoplasma capsulatum ,Microbiology ,Infectious Diseases ,Tubulin ,Cytoplasm ,medicine ,biology.protein ,Mycelium ,Actin - Abstract
Summary: Immunogold electron microscopy using LR Gold as a resin was undertaken to determine the distribution of actin and tubulin within the hyphae of Histoplasma capsulatum capsulatum and H. capsulatum duboisii. Both of these proteins were found throughout the cytoplasm when probed with the appropiate monoclonal antibodies. Zusammenfassung: Immunogold-elektro-nenmikroskopische Untersuchungen uber das Verteilungsmuster von Actin und Tubulin in den Hyphen von Hktoplasma capsulatum capsulatum und H. capsulatum duboisii wurden mit LR Gold als Einbettungsmittel durchgefuhrt. Beide Gerustproteine konnten unter Venvendung entsprechender monoklonaler Antikorper in der Primarreaktion im Cytoplasma der Pilzzellen darge-stellt werden.
- Published
- 2009
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37. Sampling a weighted pest complex: caterpillars in North Korean cabbage (Brassica oleraceavar.capitata) crops
- Author
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Michael J. Furlong, H. J. Kim, Andrew J. Hamilton, Edward K. Waters, and W. S. Pak
- Subjects
Integrated pest management ,education.field_of_study ,Diamondback moth ,biology ,business.industry ,Population ,Pest control ,Plutella ,Pieris rapae ,biology.organism_classification ,Toxicology ,Insect Science ,Botany ,Brassica oleracea ,PEST analysis ,business ,education ,Ecology, Evolution, Behavior and Systematics - Abstract
The lepidopteran pests Plutella xylostella L. (Plutellidae) and Pieris rapae L. (Pieridae: Pierini) are responsible for major yield losses of cabbage, Brassica oleracea L. (Brassicaceae), in North Korea. Preliminary integrated pest management (IPM) programmes using economic thresholds (ETs) to schedule insecticide applications have proved promising and have demonstrated marked increases in yield compared to standard farming practice, which relies heavily on synthetic insecticides. To use ETs effectively on a routine basis, farmers need efficient yet sufficiently precise methods of surveying crops for pests. Here we construct and validate binomial sequential sampling plans for the two-species pest complex and for P. rapae alone. The recommended plans would be practical to implement, demanding maximum sample sizes below 50 plants, and proved very slightly conservative with respect to classifying the population relative to the ET (i.e., they were slightly more likely to suggest control at the ET than not).
- Published
- 2009
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38. The influence of management practice on the spatial distribution of Lepidopteran pests in Brassica crops in the Democratic People's Republic of Korea: implications for sequential sampling plans
- Author
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Andrew J. Hamilton, Graham Hepworth, Michael J. Furlong, Hyunggun Kim, W. S. Pak, and Edward K. Waters
- Subjects
Integrated pest management ,biology ,Ecology ,business.industry ,Agroforestry ,Brassica ,Pest control ,Plutella ,Distribution (economics) ,Pieris rapae ,biology.organism_classification ,Spatial distribution ,PEST analysis ,business ,Ecology, Evolution, Behavior and Systematics - Abstract
Plutella xylostella and Pieris rapae are the key components of a pest complex that attacks Brassica crops in the Democratic People’s Republic of Korea (DPRK). We examined the spatial distributions of these insects within crops both as individual species and when combined as a standard insect that was derived from their relative feeding rates. The influence of standard co-operative management practice and an integrated pest management (IPM) strategy on the dispersion of the standard insect was tested. Iwao’s m* − m relation was then used to describe the distribution of standard insects by management categories and of Pieris rapae using all data. Pest management practices only affected the distribution of the species when they were combined into standard insects. Enumerative sampling plans were therefore designed for standard insects based on population data derived from IPM-managed fields and for Pieris rapae from population data from all experimental fields. The presented plans have the potential to make a significant contribution to managing lepidopteran pests in the DPRK. The approach will be useful in the design of sequential sampling plans for other geographical regions where these pests co-occur and can also contribute to the development of sequential sampling plans for other pest complexes for which standard insects can be derived.
- Published
- 2009
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39. Analysis of the enzymatic activity of mycelial and yeast phases of Penicillium marneffei
- Author
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Andrew J. Hamilton, Sirida Youngchim, and Nongnuch Vanittanakom
- Subjects
chemistry.chemical_classification ,Infectious Diseases ,Enzyme ,biology ,chemistry ,biology.protein ,General Medicine ,Penicillium marneffei ,biology.organism_classification ,Enzyme assay ,Mycelium ,Yeast ,Microbiology - Published
- 2008
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40. Appraisal of random and systematic land cover transitions for regional water balance and revegetation strategies
- Author
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Frank Stagnitti, Andrew J. Hamilton, Daniel Ierodiaconou, and Vincent L. Versace
- Subjects
Ecology ,Land use ,Agroforestry ,Land-use planning ,Groundwater recharge ,Land cover ,Water resources ,Water balance ,Environmental science ,Plant cover ,Animal Science and Zoology ,Revegetation ,Agronomy and Crop Science - Abstract
This study describes the use of landscape transition analysis as a means for effective basin management. Land cover transitions from 1995 to 2002 were analyzed using a cross-tabulation matrix for an important economic zone in south-west Victoria, Australia. Specifically, the matrix was used to determine whether the transitions were random or systematic. Random landscape transitions occur when a land cover replaces other land covers in proportion to their availability. Systematic landscape transitions occur when there are deviations from random patterns, and land use types ‘target’ other land use types for replacement. The analysis was conducted with 11 land cover categories and showed that dryland pastures have been systematically losing area to dryland crops and blue gum (Eucalyptus globulus) plantations. Dryland crops have systematically expanded in the north-east of the catchment, an area where increasing in-stream salinization has occurred concurrently with this transition. The systematic expansion of the blue gum plantations has been predominantly in the south-west of the catchment and has the potential to reduce stream flows and groundwater recharge in an already water-stressed region, as blue gums use more water than the dryland pastures they are replacing. All other transitions were largely random. These findings have implications for land use planning in the study area for regional water balance and revegetation strategies. Landscape transition analysis is a cost-effective means of contributing to the management of water resources at a regional scale, and is highly recommended for future basin planning.
- Published
- 2008
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41. Cauliflower mosaic virus protein P6 is a suppressor of RNA silencing
- Author
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Justin Holt, Andrew J. Love, Andrew J. Hamilton, Janet Laird, Joel J. Milner, and Ari Sadanandom
- Subjects
Small interfering RNA ,Transgene ,Green Fluorescent Proteins ,Arabidopsis ,Down-Regulation ,Biology ,Green fluorescent protein ,Viral Proteins ,Caulimovirus ,Virology ,Gene silencing ,RNA, Small Interfering ,Plant Diseases ,Virulence ,fungi ,food and beverages ,RNA ,Amplicon ,Plants, Genetically Modified ,biology.organism_classification ,Molecular biology ,Plant Leaves ,RNA silencing ,RNA Interference ,Cauliflower mosaic virus - Abstract
We infected a transgenic Arabidopsis line (GxA), containing an amplicon-silenced 35S : : GFP transgene, with cauliflower mosaic virus (CaMV), a plant pararetrovirus with a DNA genome. Systemically infected leaves showed strong GFP fluorescence and amplicon transcripts were detectable in Northern blots, indicating that silencing of GFP had been suppressed during CaMV-infection. Transgenic Arabidopsis lines expressing CaMV protein P6, the major genetic determinant of symptom severity, were crossed with GxA. Progeny showed strong GFP fluorescence throughout and amplicon transcripts were detectable in Northern blots, indicating that P6 was suppressing local and systemic silencing. However, levels of 21 nt siRNAs derived from the GFP transgene were not reduced. In CaMV-infected plants, the P6 transgene did not reduce levels of CaMV leader-derived 21 and 24 nt siRNAs relative to levels of CaMV 35S RNA. These results demonstrate that CaMV can efficiently suppress silencing of a GFP transgene, and that P6 acts as a silencing suppressor.
- Published
- 2007
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42. Quantitative Assessment of Severity of Mitral Regurgitation by Serial Echocardiography in a Multicenter Clinical Trial of Percutaneous Mitral Valve Repair
- Author
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Kimberly Kraybill, Ivor L. Gerber, Hal S. Wasserman, Susan E. Wiegers, John D. Merlino, Patrick L. Whitlow, Frank E. Silvestry, Andrew J. Hamilton, Sarah G. Weeks, L. Leonardo Rodriguez, Randy Martin, Peter C. Block, Alan Zunamon, Marco R. Di Tullio, Shunichi Homma, Elyse Foster, Yan Zhang, Ted Feldman, William J. Stewart, Howard C. Herrmann, and William A. Gray
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Male ,medicine.medical_specialty ,Effective Regurgitant Orifice Area ,Severity of Illness Index ,Internal medicine ,Mitral valve ,Multicenter trial ,Severity of illness ,medicine ,Humans ,Prospective Studies ,Cardiac Surgical Procedures ,Mitral regurgitation ,Vena contracta ,business.industry ,Mitral Valve Insufficiency ,Middle Aged ,Echocardiography, Doppler, Color ,medicine.anatomical_structure ,Pulmonary Veins ,Regional Blood Flow ,Regurgitant fraction ,Cardiology ,Feasibility Studies ,Mitral Valve ,Female ,Cardiology and Cardiovascular Medicine ,business ,Percutaneous Mitral Valve Repair ,Follow-Up Studies - Abstract
The aims of the echocardiographic substudy of this multicenter trial were to evaluate the use of quantitative assessment of mitral regurgitation (MR) severity using serial echocardiography and to assess the efficacy of percutaneous mitral valve repair. Previous surgical repair studies did not use quantitative echocardiographic methods. Results of a percutaneous mitral valve repair clip device in a core echocardiographic laboratory were evaluated. Published parameters for quantifying MR were used in a systematic protocol to qualify patients for study entry and evaluate treatment efficacy at discharge and 6 months after clip repair. Baseline results were presented for 55 patients, and follow-up results, for 49. Ninety-eight percent of required echocardiographic studies were submitted to the core laboratory, and85% of required measurements were possible. At baseline, mean regurgitant volume was 54.8 +/- 24 ml, regurgitant fraction was 46.9 +/-16.2%, effective regurgitant orifice area was 0.71 +/- 0.40 cm(2), and vena contracta width was 0.66 +/- 0.20 cm. Based on a severity scale of 1 to 4, mean color flow grade was 3.4 +/- 0.7, and mean pulmonary vein flow was 2.8 +/- 1.2. In patients with a clip at 6 months, all measurements of MR severity were significantly decreased versus baseline, with mean regurgitant volume decreased from 50.3 to 27.5 ml (change -22.8 ml; p0.0001), regurgitant fraction from 44.6% to 28.9% (change -15.7%; p0.0001), color flow grade from an average of 3.4 to 1.8 (change -1.6; p0.0001), and pulmonary vein flow from 2.8 to 1.8 (change -1.0; p0.0018). In conclusion, quantitative assessment of MR is feasible in a multicenter trial, and percutaneous mitral repair with the MitraClip produces a sustained decrease in MR severity to moderate or less foror =6 months.
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- 2007
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43. Wastewater Irrigation: The State of Play
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Peta Maher, Andrew J. Hamilton, Frank Stagnitti, Kurt K. Benke, Simone L. Kreidl, and Xianzhe Xiong
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Catchment hydrology ,Water resources ,Irrigation ,Food security ,Resource (biology) ,Wastewater ,Environmental protection ,Sustainability ,Environmental engineering ,Soil Science ,Environmental science ,Livelihood - Abstract
As demand for fresh water intensifies, wastewater is frequently being seen as a valuable resource. Furthermore, wise reuse of wastewater alleviates concerns attendant with its discharge to the environment. Globally, around 20 million ha of land are irrigated with wastewater, and this is likely to increase markedly during the next few decades as water stress intensifies. In 1995, around 2.3 billion people lived in water-stressed river basins and this could increase to 3.5 billion by 2025. We review the current status of wastewater irrigation by providing an overview of the extent of the practice throughout the world and through synthesizing the current understanding of factors influencing sustainable wastewater irrigation. A theme that emerges is that wastewater irrigation is not only more common in water-stressed regions such as the Near East, but the rationale for the practice also tends to differ between the developing and developed worlds. In developing nations, the prime drivers are livelihood dependence and food security, whereas environmental agendas appear to hold greater sway in the developed world. The following were identified as areas requiring greater understanding for the long-term sustainability of wastewater irrigation: (i) accumulation of bioavailable forms of heavy metals in soils, (ii) environmental fate of organics in wastewater-irrigated soils, (iii) influence of reuse schemes on catchment hydrology, including transport of salt loads, (iv) risk models for helminth infections (pertinent to developing nations), (v) microbiological contamination risks for aquifers and surface waters, (vi) transfer efficiencies of chemical contaminants from soil to plants, (vii) health effects of chronic exposure to chemical contaminants, and (viii) strategies for engaging the public.
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- 2007
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44. Echocardiographic Guidance and Assessment of Percutaneous Repair for Mitral Regurgitation With the Evalve MitraClip: Lessons Learned From EVEREST I
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Allan Schwartz, Elyse Foster, Howard C. Herrmann, L. Leonardo Rodriguez, Randolph P. Martin, Hal S. Wasserman, Sameer Rohatgi, Mark Reisman, Samir R. Kapadia, Alan Zunamon, Neil K. Goyal, Ted Feldman, Stuart J. Weiss, William A. Gray, Kimberly A. Krabill, Peter C. Block, Todd Pulerwitz, E. Murat Tuzcu, Pat Whitlow, John D. Merlino, William J. Stewart, Susan E. Wiegers, Frank E. Silvestry, Andrew J. Hamilton, and Shunichi Homma
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Cardiac Catheterization ,medicine.medical_specialty ,Percutaneous ,medicine.medical_treatment ,Severity of Illness Index ,Mitral valve ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Cardiac Surgical Procedures ,CLIPS ,Aged ,computer.programming_language ,Cardiac catheterization ,Mitral regurgitation ,business.industry ,MitraClip ,Mitral Valve Insufficiency ,Equipment Design ,Echocardiography, Doppler, Color ,Surgery ,Cardiac surgery ,Clinical trial ,Treatment Outcome ,medicine.anatomical_structure ,Cardiology and Cardiovascular Medicine ,business ,computer ,Blood Flow Velocity ,Echocardiography, Transesophageal - Abstract
Objective Percutaneous mitral repair is rapidly developing as an alternative to cardiac surgery in select patients. The Evalve percutaneous E2E system uses the MitraClip to replicate the surgical suture-based approach. This procedure requires real-time echocardiographic guidance in a unique and significant collaboration between echocardiographer and interventionalist. transesophageal echocardiography (TEE) is used as the primary imaging modality to guide this procedure and is essential to its success. Methods In EVEREST I, the US multicenter phase I safety and feasibility trial, 47 patients with 3 or 4+ mitral regurgitation (MR) were enrolled. The trial involved a standardized echocardiographic imaging protocol with a standardized anatomic-based vocabulary, predetermined standard TEE views, preprocedural strategy meetings, and display of echocardiographic aids to optimize communication and procedural efficiency during placement of the clip. Results TEE guidance facilitated the creation of a double-orifice mitral valve in all 47 patients enrolled (100%), and 40 patients were discharged with 1 or more clips (85%). At discharge, successful placement of a clip and ≤ 2+ MR was present in 34 patients (74%). The standardized approach contributed to a reduction in the time to perform the procedure over the course of the trial at both initial and new sites. Conclusions TEE is essential to the guidance of percutaneous MitraClip E2E repair. A streamlined approach to echocardiographic guidance, using predetermined standardized views, a common anatomic-based vocabulary, preprocedural strategy meetings, and a display of echocardiographic aids in the catheterization laboratory shortens the procedure time and allows for efficient percutaneous repair.
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- 2007
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45. Regional-scale models for relating land cover to basin surface-water quality using remotely sensed data in a GIS
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A.-M. Boland, Frank Stagnitti, M. T. Walter, Daniel Ierodiaconou, Andrew J. Hamilton, Vincent L. Versace, and B. Mitchell
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Hydrology ,geography ,Time Factors ,Watershed ,geography.geographical_feature_category ,Victoria ,Land use ,Water Pollution ,Drainage basin ,General Medicine ,Vegetation ,Land cover ,Plants ,Sodium Chloride ,Management, Monitoring, Policy and Law ,Pollution ,Salinity ,Rivers ,Geographic Information Systems ,Environmental science ,Plant cover ,Dryland salinity ,Environmental Monitoring ,General Environmental Science - Abstract
Plant-based management systems implementing deep-rooted, perennial vegetation have been identified as important in mitigating the spread of secondary dryland salinity due to its capacity to influence water table depth. The Glenelg Hopkins catchment is a highly modified watershed in the southwest region of Victoria, where dryland salinity management has been identified as a priority. Empirical relationships between the proportion of native vegetation and in-stream salinity were examined in the Glenelg Hopkins catchment using a linear regression approach. Whilst investigations of these relationships are not unique, this is the first comprehensive attempt to establish a link between land use and in-stream salinity in the study area. The results indicate that higher percentage land cover with native vegetation was negatively correlated with elevated in-stream salinity. This inverse correlation was consistent across the 3 years examined (1980, 1995, and 2002). Recognising the potential for erroneously inferring causal relationships, the methodology outlined here was both a time and cost-effective tool to inform management strategies at a regional scale, particularly in areas where processes may be operating at scales not easily addressed with on-site studies.
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- 2007
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46. Quantitative microbial risk assessment: uncertainty and measures of central tendency for skewed distributions
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Kurt K. Benke and Andrew J. Hamilton
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Environmental Engineering ,Central tendency ,Function (mathematics) ,Imprecise probability ,Risk Estimate ,Statistics ,Log-normal distribution ,Econometrics ,Environmental Chemistry ,Geometric mean ,Safety, Risk, Reliability and Quality ,Risk assessment ,General Environmental Science ,Water Science and Technology ,Mathematics ,Arithmetic mean - Abstract
In the past, arithmetic and geometric means have both been used to characterise pathogen densities in samples used for microbial risk assessment models. The calculation of total (annual) risk is based on cumulative independent (daily) exposures and the use of an exponential dose–response model, such as that used for exposure to Giardia or Cryptosporidium. Mathematical analysis suggests that the arithmetic mean is the appropriate measure of central tendency for microbial concentration with respect to repeated samples of daily exposure in risk assessment. This is despite frequent characterisation of microbial density by the geometric mean, since the microbial distributions may be Log normal or skewed in nature. Mathematical derivation supporting the use of the arithmetic mean has been based on deterministic analysis, prior assumptions and definitions, the use of point-estimates of probability, and has not included from the outset the influence of an actual distribution for microbial densities. We address these issues by experiments using two real-world pathogen datasets, together with Monte Carlo simulation, and it is revealed that the arithmetic mean also holds in the case of a daily dose with a finite distribution in microbial density, even when the distribution is very highly-skewed, as often occurs in environmental samples. Further, for simplicity, in many risk assessment models, the daily infection risk is assumed to be the same for each day of the year and is represented by a single value, $$ \hat{p}, $$ which is then used in the calculation of p Σ, which is a numerical estimate of annual risk, P Σ, and we highlight the fact that $$ \hat{p} $$ is simply a function of the geometric mean of the daily complementary risk probabilities (although it is sometimes approximated by the arithmetic mean of daily risk in the low dose case). Finally, the risk estimate is an imprecise probability with no indication of error and we investigate and clarify the distinction between risk and uncertainty assessment with respect to the predictive model used for total risk assessment.
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- 2007
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47. RIRA: A tool for conducting health risk assessments for irrigation of edible crops with recycled water
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Sarath C. Kumarage, Andrew J. Hamilton, Robert R. Premier, and Frank Stagnitti
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Risk analysis ,Engineering ,Irrigation ,Resource (biology) ,business.industry ,Environmental engineering ,Forestry ,Horticulture ,Reclaimed water ,Computer Science Applications ,Agriculture ,business ,Risk assessment ,Agronomy and Crop Science ,Environmental planning ,Risk management ,Disease burden - Abstract
Irrigation of food crops with reclaimed water is becoming increasingly common, owing to a combination of agricultural, environmental, social and economic drivers. Despite the benefits of irrigation with recycled water, the practice does nonetheless pose risks to human health, most notably through contamination of produce with human pathogens. Microbiological risks can be characterised through a modelling process known as Quantitative Microbial Risk Assessment (QMRA). The construction of a QMRA model is an essential component of risk management for any recycled water irrigation scheme. This can, however, be a tedious and technically demanding process. Here we present the decision support tool Recycled water Irrigation Risk Analysis (RIRA), which can be used by water resource and public health managers to conduct QMRAs for recycled water irrigation. RIRA is designed to accommodate a wide range of scenarios. Once the user has defined the pathogen of interest and the exposure scenario, RIRA uses pathogen-specific dose-response models to calculate the annual risk of infection. This is the primary end-point of the model, but given adequate information RIRA can also calculate a disease burden metric, the Disability Adjusted Life-Year (DALY), which accounts for the severity and duration of a disease. The generic and flexible structure of RIRA means that it can be used to conduct risk assessments in accordance with the methods recommended in major recycled water guidelines.
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- 2007
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48. Potential microbial and chemical hazards to waterbirds at the Western Treatment Plant
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Andrew J. Hamilton
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biology ,business.industry ,Ecology ,fungi ,food and beverages ,Sewage ,Management, Monitoring, Policy and Law ,biology.organism_classification ,Hazardous waste ,Environmental protection ,Waterfowl ,Environmental science ,Sewage treatment ,business ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
The Western Treatment Plant, a major sewage treatment plant west of Melbourne, Australia, is widely regarded as a significant conservation site for waterbirds. But experiences from various parts of the world suggest that sewage can also be hazardous to waterbirds, and has probably been responsible for mass-kill events. The intent of this contribution is to raise awareness about the potential for adverse impacts of sewage treatment plants on waterbirds, and to stimulate debate on the issue, with the ultimate objective of developing appropriate management strategies to mitigate the risk of mass kills.
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- 2007
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49. Uncertainty analysis and risk assessment in the management of environmental resources
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Andrew J. Hamilton, Kim Lowell, and Kurt K. Benke
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Risk analysis (engineering) ,Data variability ,Project commissioning ,Computer science ,Ecology (disciplines) ,Geography, Planning and Development ,Management, Monitoring, Policy and Law ,Social science ,Risk assessment ,Environmental resource ,Uncertainty analysis ,Variety (cybernetics) ,Terminology - Abstract
Analysis of uncertainty is often neglected in the evaluation of complex systems (such as predictive models in hydrology or ecology, or environmental processes). Decisions and actions based on such systems may be error-prone for a variety of reasons, including lack of information, input errors or data variability. Research in uncertainty addresses this problem by investigating the causes of uncertainty and the characterisation of uncertainty associated with limited information. The article describes and compares definitions and terminology in uncertainty analysis and reviews suggested classifications. Traditional risk assessment is not directly equivalent to uncertainty analysis. The authors discuss distinctions and applications in various contexts relating to environmental management.
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- 2007
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50. Zoonotic Transmission of Waterborne Disease: A Mathematical Model
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Harvinder S. Sidhu, Edward K. Waters, Michelle Dunbar, Andrew J. Hamilton, and Leesa A. Sidhu
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0301 basic medicine ,Giardiasis ,General Mathematics ,030106 microbiology ,Immunology ,Water source ,Cryptosporidiosis ,Biology ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,law.invention ,Toxicology ,03 medical and health sciences ,Linear stability analysis ,law ,Zoonoses ,Waterborne Diseases ,medicine ,Animals ,Humans ,Potential source ,General Environmental Science ,Disease Reservoirs ,Pharmacology ,Ecology ,General Neuroscience ,Waterborne diseases ,Water ,Mathematical Concepts ,medicine.disease ,030104 developmental biology ,Transmission (mechanics) ,Computational Theory and Mathematics ,General Agricultural and Biological Sciences ,Rural australia - Abstract
Waterborne parasites that infect both humans and animals are common causes of diarrhoeal illness, but the relative importance of transmission between humans and animals and vice versa remains poorly understood. Transmission of infection from animals to humans via environmental reservoirs, such as water sources, has attracted attention as a potential source of endemic and epidemic infections, but existing mathematical models of waterborne disease transmission have limitations for studying this phenomenon, as they only consider contamination of environmental reservoirs by humans. This paper develops a mathematical model that represents the transmission of waterborne parasites within and between both animal and human populations. It also improves upon existing models by including animal contamination of water sources explicitly. Linear stability analysis and simulation results, using realistic parameter values to describe Giardia transmission in rural Australia, show that endemic infection of an animal host with zoonotic protozoa can result in endemic infection in human hosts, even in the absence of person-to-person transmission. These results imply that zoonotic transmission via environmental reservoirs is important.
- Published
- 2015
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