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1. Characterizing ruminal acidosis risk: A multiherd, multicountry study

Author

Golder, HM, LeBlanc, SJ, Duffield, T, Rossow, HA, Bogdanich, R, Hernandez, L, Block, E, Rehberger, J, Smith, AH, Thomson, J, and Lean, IJ

Subjects
Agricultural, Veterinary and Food Sciences, Animal Production, Female, Animals, Cattle, Ammonia, Rumen, Milk, Lactation, Fatty Acids, Volatile, Diet, Lactic Acid, Carbohydrates, Acidosis, Fermentation, Hydrogen-Ion Concentration, Animal Feed, Cattle Diseases, discriminant analysis, microbiome, ruminal acidosis, valerate, Food Sciences, Dairy & Animal Science, Animal production, Food sciences, Veterinary sciences
Abstract

A multicenter observational study was conducted on early lactation Holstein cows (n = 261) from 32 herds from 3 regions (Australia, AU; California, CA; and Canada, CAN) to characterize their risk of acidosis into 3 groups (high, medium, or low) using a discriminant analysis model previously developed. Diets ranged from pasture supplemented with concentrates to total mixed ration (nonfiber carbohydrates = 17 to 47 and neutral detergent fiber = 27 to 58% of dry matter). Rumen fluid samples were collected

Published
2023

3. Implications of the loess record for Holocene climate and human settlement in Heye Catchment, Jiuzhaigou, eastern Tibetan Plateau, Sichuan, China

Author

Smith, AH, Collins, BD, Keen-Zebert, A, d'Alpoim Guedes, J, Hein, A, Womack, A, McGuire, C, Feathers, J, Persico, L, Fiallo, D, Tang, Y, and Simonson, B

Subjects
Arts and Humanities (miscellaneous), General Earth and Planetary Sciences, Earth-Surface Processes
Abstract

We examine the Holocene loess record in the Heye Catchment on the margins of the Tibetan Plateau (TP) and China Loess Plateau (CLP) to determine: the region to which the Heye Catchment climate is more similar; temporal change in wind strength; and modification of the loess record by mass wasting and human activity. Luminescence and radiocarbon dating demonstrate loess deposited in two periods: >11–8.6 ka and

Published
2022

4. Arsenic-induced skin lesions among Atacameño people in Northern Chile despite good nutrition and centuries of exposure.

Author

Smith, AH, Arroyo, AP, Mazumder, DN, Kosnett, MJ, Hernandez, AL, Beeris, M, Smith, MM, and Moore, LE

Subjects
Clinical Research, Foodborne Illness, Prevention, Cancer, Zero Hunger, Adolescent, Adult, Arsenic, Child, Chile, Diet, Environmental Exposure, Female, Humans, Incidence, Indians, South American, Male, Nutritional Status, Skin Diseases, Water Supply, drinking water, nutrition, skin lesions, Environmental Sciences, Medical and Health Sciences, Toxicology
Abstract

It has been suggested that the indigenous Atacameño people in Northern Chile might be protected from the health effects of arsenic in drinking water because of many centuries of exposure. Here we report on the first intensive investigation of arsenic-induced skin lesions in this population. We selected 11 families (44 participants) from the village of Chiu Chiu, which is supplied with water containing between 750 and 800 microg/L inorganic arsenic. For comparison, 8 families (31 participants) were also selected from a village where the water contains approximately 10 microg/L inorganic arsenic. After being transported to the nearest city for blind assessment, participants were examined by four physicians with experience in studying arsenic-induced lesions. Four of the six men from the exposed village, who had been drinking the contaminated water for more than 20 years, were diagnosed with skin lesions due to arsenic, but none of the women had definite lesions. A 13-year-old girl had definite skin pigmentation changes due to arsenic, and a 19-year-old boy had both pigmentation changes and keratoses on the palms of his hands and the soles of his feet. Family interviews identified a wide range of fruits and vegetables consumed daily by the affected participants, as well as the weekly intake of red meat and chicken. However, the prevalence of skin lesions among men and children in the small population studied was similar to that reported with corresponding arsenic drinking water concentrations in both Taiwan and West Bengal, India--populations in which extensive malnutrition has been thought to increase susceptibility.

Published
2000

5. Arsenic methylation patterns before and after changing from high to lower concentrations of arsenic in drinking water.

Author

Hopenhayn-Rich, C, Biggs, ML, Kalman, DA, Moore, LE, and Smith, AH

Subjects
Environmental Sciences, Pollution and Contamination, Foodborne Illness, Genetics, Clinical Research, Adult, Aged, Aged, 80 and over, Arsenic, Arsenicals, Biotransformation, Cacodylic Acid, Chile, Female, Humans, Male, Methylation, Middle Aged, Water Pollutants, Water Supply, arsenic, arsenic methylation, arsenic speciation, exposure change, intervention studies, water pollution, Medical and Health Sciences, Toxicology, Biomedical and clinical sciences, Environmental sciences, Health sciences
Abstract

Inorganic arsenic (In-As), an occupational and environmental human carcinogen, undergoes biomethylation to monomethylarsonate (MMA) and dimethylarsinate (DMA). It has been proposed that saturation of methylation capacity at high exposure levels may lead to a threshold for the carcinogenicity of In-As. The relative distribution of urinary In-As, MMA, and DMA is used as a measure of human methylation capacity. The most common pathway for elevated environmental exposure to In-As worldwide is through drinking water. We conducted a biomarker study in northern Chile of a population chronically exposed to water naturally contaminated with high arsenic content (600 micrograms/l). In this paper we present the results of a prospective follow-up of 73 exposed individuals, who were provided with water of lower arsenic content (45 micrograms/l) for 2 months. The proportions of In-As, MMA, and DMA in urine were compared before and after intervention, and the effect of other factors on the distribution of arsenic metabolites was also analyzed. The findings of this study indicate that the decrease in arsenic exposure was associated with a small decrease in the percent In-As in urine (from 17.8% to 14.6%) and in the MMA/DMA ratio (from 0.23 to 0.18). Other factors such as smoking, gender, age, years of residence, and ethnicity were associated mainly with changes in the MMA/DMA ratio, with smoking having the strongest effect. Nevertheless, the factors investigated accounted for only about 20% of the large interindividual variability observed. Genetic polymorphisms in As-methylating enzymes and other co-factors are likely to contribute to some of the unexplained variation. The changes observed in the percent In-As and in the MMA/DMA ratio do not support an exposure-based threshold for arsenic methylation in humans.

Published
1996

6. Methylation study of a population environmentally exposed to arsenic in drinking water.

Author

Hopenhayn-Rich, C, Biggs, ML, Smith, AH, Kalman, DA, and Moore, LE

Subjects
Environmental Sciences, Pollution and Contamination, Clinical Research, Patient Safety, Foodborne Illness, Clinical Trials and Supportive Activities, Adolescent, Adult, Aged, Aged, 80 and over, Arsenic, Arsenicals, Cacodylic Acid, Chile, Environmental Exposure, Female, Humans, Male, Methylation, Middle Aged, Regression Analysis, Water Pollutants, Water Supply, Medical and Health Sciences, Toxicology, Biomedical and clinical sciences, Environmental sciences, Health sciences
Abstract

Methylation is considered the detoxification pathway for inorganic arsenic (InAs), an established human carcinogen. Urinary speciation analysis is used to assess the distribution of metabolites [monomethylarsonate (MMA), dimethylarsinate (DMA), and unmethylated arsenic (InAs)], as indicators of methylation capacity. We conducted a large biomarker study in northern Chile of a population chronically exposed to high levels of arsenic in drinking water. We report the results of the methylation study, which focused on the effects of exposure and other variables on the percent InAs, MMA, DMA, and the ratio of MMA to DMA in urine. The study consisted of 122 people in a town with arsenic water levels around 600 micrograms/l and 98 participants in a neighboring town with arsenic levels in water of about 15 micrograms/l. The corresponding mean urinary arsenic levels were 580 micrograms/l and 60 micrograms/l, of which 18.4% and 14.9% were InAs, respectively. The main differences were found for MMA:DMA; exposure, smoking, and being male were associated with higher MMA:DMA, while longer residence, Atacameño ethnicity, and being female were associated with lower MMA:DMA. Together, these variables explained about 30% of the variability in MMA:DMA. Overall, there was no evidence of a threshold for methylation capacity, even at very high exposures, and the interindividual differences were within a much wider range than those attributed to the variables investigated. The differences in percent InAs were small and within the ranges of other studies of background exposure levels. The biological significance of MMA:DMA, which was more than 1.5 times greater in the exposed group, and its relationship to sex, length of exposure, and ethnicity need further investigation because its relevance to health risk is not clear.

Published
1996

7. The Development of Strategies for the Management and Research of Foliar Pathogens on Eucalypt Plantations: Using Mycosphaerella as a Case Study

Author

Smith, AH

Subjects
Forest health and pathology
Abstract

Foliar pathogens are capable of severely reducing the productivity and stem form of eucalypt trees in plantations. Mycosphaerella is one of the most severe defoliating pathogens to eucalypts worldwide. In Australia Mycosphaerella leaf disease (MLD) has produced episodes of severe defoliation in Tasmania, Gippsland and south-west Western Australia. Mycosphaerella is one of the most researched pathogens of eucalypts, however the majority of studies have concentrated on the taxonomy of pathogens and investigating their geographical and host ranges. In this thesis, MLD has been chosen as a model system to develop and apply new technologies to researching foliar pathogens. Research was conducted in the four main areas of disease assessment, growth impacts, molecular detection and resistance mechanisms. Acquiring accurate and repeatable damage estimates at a tree level is essential for calculating damage at plantation and estate levels; especially where data will be used for computer generated modelling using programs such as Maestra or CABALA. Repeated assessments using the Crown Damage Index (CDI) tested the suitability of the method to provide reliable, objective and repeatable results. Nine assessors, with varying levels of experience, estimated damage on three plots of fifty trees each (3-4 years old), to obtain an understanding of the subjectivity of assessing damage caused by insects (e.g. Chrysophtharta spp.) and fungal pathogens (e.g. Mycosphaerella spp.) on Eucalyptus globulus Labill. Damage levels were measured by destructive sampling to enable direct comparisons between estimates and damage levels to be made. The most experienced assessors provided the most repeatable estimates and were generally the most accurate. The incidence of foliar necrosis was the least subjective measure while defoliation was the most subjective and the least accurate of the indices measured. All assessors, regardless of experience, were able to predict the Crown Damage Index (a combined index of all damage classes) to within 12 % of measured damage levels. Further modification of the CDI in a separate study on younger trees (1-2 years old) further reduced the errors involved with damage estimates to within 4 % of actual damage levels. Despite the importance of Mycosphaerella species as significant defoliating pathogens of temperate plantation eucalypts such as E. globulus, there have been no studies to investigate the effects of Mycosphaerella damage on growth of young trees measured through to rotation length. From the results of two growth trials, one short term and one longer term (tree growth was monitored until 3 and 6 years old, respectively), the damage threshold (level of damage before there were significant growth effects) was estimated to be approximately 20 %. In both trials, losses in volume were only observed until trees changed to adult foliage at which point the growth rate returned to that of the control trees. We predicted that with less than 80 % damage, growth rates follow a type 1 growth response, i.e. after an initial growth loss damaged trees recover and have a growth rate that is parallel with control trees. Above 80 % loss of effective leaf area, it is predicted that growth rates of control trees and damaged trees are permanently divergent. To give a longterm estimate of impact, the growth of trees in the longer term trial were modelled to rotation length. After 25 years growth (rotation length) it is estimated that a loss of one year's growth will occur as a result of the MLD damage observed in this trial. One year was also the length of time that juvenile foliage was exposed to greater than 20% damage. A nested PCR detection method was applied to leaves and stems infected by MLD to detect the five most common Mycosphaerella species that occur in Tasmania. Leaf samples were taken from E. globulus and Eucalyptus nitens (Deane and Maid.) Maid. plantations in the northern regions of Tasmania and native re-growth in the north-east of Tasmania. For the first time it has been conclusively shown that in excess of five Mycosphaerella species can coexist in E. globulus leaves and four in E. nitens leaves, including a record of Mycosphaerella nubilosa (Cooke) Hansf. on E. nitens which has only been documented once before. Samples from native Eucalyptus regnans (Thum) Lindaure provided evidence that the co-existence of several Mycosphaerella species on a single lesion may occur outside the plantation environment. The molecular detection test was a rapid, reliable and cost-effective method in comparison with classical mycological methods for the identification and differentiation of species associated with MLD on eucalypts. These studies have highlighted the potential for multiple pathogenic species of Mycosphaerella to simultaneously occupy the same niche. The Mycosphaerella detection technique was also applied to determine the presence of species associated with MLD in leaf lesions of varying development, including asymptomatic tissue. Symptoms characteristic of putative Mycosphaerella lesions, collected from commercial E. globulus and E. nitens plantations, were categorised into five stages of development with asymptomatic tissue designated as the stage prior to any symptom expression. Lesions in all categories, including some asymptomatic leaf tissue, tested positive for the presence of up to four ycosphaerella species. The number and composition of species within a lesion varied between early and late stage lesions, with trends occurring for the most pathogenic species to occupy necrotic and reproductive lesions exclusively (E. nitens) or with only one other species (E. globulus). Early detection of Mycosphaerella species in asymptomatic leaves and at any stage of lesion maturity will facilitate more accurate, rapid and broad scale screening of plantations for ecological and epidemiological investigations at earlier stages of disease development. Effective and reproducible artificial inoculation techniques for MLD have not been developed; the confirmation of Mycosphaerella species in naturally infected early lesions using the nested PCR detection system enables the study of field infected leaves to determine the effects of infection on host physiology and resistance. The timing and strength of necrophylactic periderm formation, deposition of defence chemicals and accumulation/retention of photosynthetic pigments were compared between MLD susceptible E. globulus and the more MLD resistant E. nitens after infection of the leaves with Mycosphaerella species. Resistance of E. nitens, as observed in southern Australia, was attributed to the speed of necrophylactic periderm formation, which was directly related to the amount and type of cell division occurring in the mesophyll cells. In E. nitens the necrophylactic periderm is formed early in lesion development by cellular division of mesophyll cells which were quickly reinforced with lignin, suberin and other polyphenolics. It is suggested that the rapid nature of necrophylactic periderm formation in leaves of E. nitens was due to the presence of isobilateral palisade layers and the need for less cellular division to fill intracellular spaces and form a continuous barrier of cells. In E. globulus, which has only one adaxial palisade layer, the necrophylactic periderm was formed more slowly and in a distorted fashion. It was primarily formed through hypertrophic changes to existing cells and limited cell divisions. Deposits of lignin and suberin in the cells of the necrophylactic periderm did not occur in E. globulus until later stages of lesion development, and in many cases the necrophylactic periderm appeared to be ineffective in preventing further disease development. From this study of necrophylactic periderm formation, it was suggested that increased mesophyll density within a leaf may be linked with the speed and shape of necrophylactic periderms that are formed after infection by Mycosphaerella species; thus the more resistant species/families are able to restrict pathogen spread more effectively than susceptible species/families. Under the same environmental conditions and inoculum load, northern NSW provenances of E. nitens have been observed to be more resistant to MLD than southern NSW provenances. Using histological methods, one provenance from each distribution were investigated with respect to constitutive anatomy. The cellular and histochemical changes after infection by Mycosphaerella species that led to barrier zone formation, including accumulation of defence compounds such as suberin, lignin and flavanoids were also compared. Leaves of resistant provenances were significantly thinner, had a higher proportion of palisade mesophyll and reduced intracellular airspace compared with those from the susceptible provenance. After infection, more cellular division was observed in sections from resistant leaves and the necrophylactic periderm formed was more organised, continuous, suberised and lignified than necrophylactic periderms formed in susceptible leaves. It is suggested that higher constitutive proportions of cell-dense palisade layers and thinner leaves can reduce the cellular division required to form of necrophylactic periderms after injury and compartmentalise pathogens more rapidly. More compact palisade layers may also play a role in the slowing or prevention of infection as some Mycosphaerella species may not be able to penetrate tightly packed mesophyll cells. Resistance of E. globulus juvenile foliage to MLD has been shown to be under high genetic control. Differences between pairs of resistant and susceptible families, in constitutive traits of juvenile leaves such as stomatal density (counted with wax on and with wax removed), leaf density, total phenolics and total leaf wax was assessed on juvenile leaves. Four resistant and susceptible pairs of families were compared including one inter-provenance, one intra-provenance and two wi...

Published
2023
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8. Cancer risks from arsenic in drinking water.

Author

Smith, AH, Hopenhayn-Rich, C, Bates, MN, Goeden, HM, Hertz-Picciotto, I, Duggan, HM, Wood, R, Kosnett, MJ, and Smith, MT

Subjects
Environmental Sciences, Pollution and Contamination, Cancer, Lung, Prevention, Foodborne Illness, Lung Cancer, Clean Water and Sanitation, Animals, Arsenic, Case-Control Studies, Dose-Response Relationship, Drug, Female, Humans, Kidney Neoplasms, Liver Neoplasms, Lung Neoplasms, Male, Maximum Allowable Concentration, Mice, Neoplasms, Rats, Rats, Wistar, Taiwan, United States, United States Environmental Protection Agency, Urinary Bladder Neoplasms, Water Pollutants, Water Supply, Medical and Health Sciences, Toxicology, Biomedical and clinical sciences, Environmental sciences, Health sciences
Abstract

Ingestion of arsenic, both from water supplies and medicinal preparations, is known to cause skin cancer. The evidence assessed here indicates that arsenic can also cause liver, lung, kidney, and bladder cancer and that the population cancer risks due to arsenic in U.S. water supplies may be comparable to those from environmental tobacco smoke and radon in homes. Large population studies in an area of Taiwan with high arsenic levels in well water (170-800 micrograms/L) were used to establish dose-response relationships between cancer risks and the concentration of inorganic arsenic naturally present in water supplies. It was estimated that at the current EPA standard of 50 micrograms/L, the lifetime risk of dying from cancer of the liver, lung, kidney, or bladder from drinking 1 L/day of water could be as high as 13 per 1000 persons. It has been estimated that more than 350,000 people in the United States may be supplied with water containing more than 50 micrograms/L arsenic, and more than 2.5 million people may be supplied with water with levels above 25 micrograms/L. For average arsenic levels and water consumption patterns in the United States, the risk estimate was around 1/1000. Although further research is needed to validate these findings, measures to reduce arsenic levels in water supplies should be considered.

Published
1992

11. Case-control study of multiple myeloma and farming

Author

Pearce, NE, Smith, AH, Howard, JK, Sheppard, RA, Giles, HJ, and Teague, CA

Subjects
Biomedical and Clinical Sciences, Oncology and Carcinogenesis, Clinical Research, Cancer, Rare Diseases, Aged, Agricultural Workers' Diseases, Animals, Cattle, Chlorophenols, Herbicides, Humans, Hypersensitivity, Male, Multiple Myeloma, New Zealand, Sheep, Public Health and Health Services, Oncology & Carcinogenesis, Oncology and carcinogenesis
Abstract

A previous case-control study which utilised the occupational information available on the New Zealand Cancer Registry found an increased risk of multiple myeloma in agricultural workers consistent with previous findings in the United States. The findings are now presented for the second phase of the study which involved interviewing 76 cases of multiple myeloma (who had been included in the previous study) together with 315 controls with other types of cancer. The previous finding on an excess of farmers in the case group was confirmed by the interview data (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.04). There were no significant differences between cases and controls regarding potential exposure to phenoxy herbicides or chlorophenols. There were also no significant differences regarding activities involving potential exposure to other agricultural chemicals, although the odds ratio for fencing work, which may involve exposure to arsenic and sodium pentachlorophenate, was 1.6 (95% confidence limits 0.9-2.7, P = 0.11). The odds ratios were significantly elevated for sheep farming (odds ratio = 1.9, 95% confidence limits 1.0-3.6, P = 0.04) and exposure to beef cattle (odds ratio = 1.7, 95% confidence limits 1.0-2.9, P = 0.05). The odds ratio was also elevated for persons reporting a history of hay fever (odds ratio = 1.9, 95% confidence limits 1.0-3.5, P = 0.05). Overall, these findings suggest that the search for the causes of elevated mortality in farmers from multiple myeloma should be directed to potential causes other than pesticide exposure.

Published
1986

12. Blood pressure and blood lead concentration in bus drivers.

Author

Sharp, DS, Osterloh, J, Becker, CE, Bernard, B, Smith, AH, Fisher, JM, Syme, SL, Holman, BL, and Johnston, T

Subjects
Cardiovascular, Hypertension, Adult, Blood Pressure, Female, Health Surveys, Humans, Lead, Male, Middle Aged, Occupational Diseases, San Francisco, Environmental Sciences, Medical and Health Sciences, Toxicology
Abstract

San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressures varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 micrograms/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (micrograms/dL) [90% C. I., -1.6, 5.3]. The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (micrograms/dL) [90% C. I., 0.1, 4.9]. These findings suggest effects of lead exposure at lower blood lead concentrations than those concentrations that have previously been linked with increases in blood pressure.

Published
1988

13. Critical mass: when does an unmanned aircraft system become a risk to commercial aviation?

Author

Dressner, M, Smith, AH, Lodewijks, G, Dressner, M, Smith, AH, and Lodewijks, G

Abstract

Unmanned Aircraft Systems (UASs) are increasing in ability, affordability andnumbers. Reports of near-misses between manned aircraft and UASs have increased markedly, eliciting concern from aviation experts and pilots that the rising number of near-misses foreshadow a catastrophic mid-air collision with a commercial aircraft, with significant loss of life. This paper aims to answer the question when should a UAS be considered a safety risk tocommercial aviation? To answer this question a literature review of current academic, government and industry published material has been conducted. Adopting the International Civil Aviation Organization (ICAO) recommended risk assessment process, four sub questions were defined and answered. The first is, what characteristic (weight, capability or type of operation) qualifies a UAS as being hazardous? A UAS is hazardous if it has the capability of being in a position that places it in conflict with commercial aviation. The second sub question is what is the likelihood of there being a conflict between a UAS and commercial aviation? The likelihood of a conflict is frequent - likely to occur many times. The third sub question is what is the severity (consequence) of the damage to an aircraft during a mid-air collision with a UAS? The severity ranges from minor (engine shutdown) to major (airframe damage). The last sub question is what strategies best mitigate the risk a UAS poses to manned aviation? Effective strategies are risk-based UAS regulation and airworthiness certification based on capability, complimented by UAS registration and operator training appropriate to the operation. Consequently, the main research question was answered: A UAS should beconsidered a safety risk when it has the capability of being in conflict with manned aircraft, either deliberately (violation) or inadvertently (system failure/loss of control) and does not incorporate Fail-Safe (geofencing) or collision avoidance (DAA) technology. Based on the ex

Published
2019

15. Sex ratio of the offspring of New Zealand phenoxy herbicide producers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

Author

't Mannetje, A, Eng, A, Walls, C, Dryson, E, Kogevinas, M, Brooks, C, McLean, D, Cheng, S, Smith, AH, and Pearce, N

Abstract

© 2017, BMJ. All rights reserved. Objectives: Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has inconsistently been associated with a decreased sex ratio of the offspring (number of male births divided by total births). We conducted a study among men and women who were employed in a New Zealand phenoxy herbicide production plant between 1969 and 1984, to study their offspring sex ratio in relation to their back-calculated TCDD serum concentrations determined in 2007/2008. Methods: A total of 127 men and 21 women reported that 355 children were conceived after starting employment at the plant. The association between their lipid-standardised TCDD serum concentrations back-calculated to the time of their offspring's birth and the probability of a male birth was estimated through logistic regression, adjusting for the age of the exposed parent at birth, current body mass index and smoking. Results: The overall sex ratio was 0.55 (197 boys, 158 girls). For fathers with serum TCDD concentrations ≥20 pg/g lipid at time of birth, the sex ratio was 0.47 (OR 0.49; 95% CI 0.30 to 0.79). The probability of a male birth decreased with higher paternal serum TCDD at time of birth (

Published
2017

17. Documentation, Digitisation and Dissemination: Preparing for the History of CSIRO

Author

Adam, Mccarthy, G, Smith, AH, Adam, Mccarthy, G, and Smith, AH

Abstract

In February 2017 Tom Spurling and Terry Healy delivered 34 A1 archive boxes of records to the eScholarship Research Centre (ESRC) at The University of Melbourne. They had been commissioned to write a history of the Commonwealth Scientific and Industrial Research Organisation (CSIRO) to complement the existing histories of CSIR and CSIRO. These boxes contained an impressive array of documents and research notes assembled for Boris Schedvin, the former CSIR/O historian. They were to support his writing of a second volume to Shaping Science and Industry (Allen & Unwin, 1987). They provide a unique overview of the history of scientific research in Australia in the late 20th Century and the evolution of CSIRO from 1949. The ESRC was commissioned to extend the existing documentation of the records (metadata), prepare for and then digitise the records and produce at least one dissemination form integrating the metadata and images. This paper outlines the scope of this project, the nature of the records, and the archival and digitisation systems, standards and strategies. The digitisation and post-digitisation processes (software and methods), including the production of derivatives is examined. Of interest is the balancing of the expectations of the researchers, and the requirement for standardised and reproducible methods that support archival documentation and digital data preservation. The paper will utilise examples from the records that focus on the history of chemistry in Australia – a selection that is interesting in its own right.

Published
2017

18. Diet and bladder cancer: a meta-analysis of six dietary variables

Author

Steinmaus, CM, Nunez, S, and Smith, AH.

Subjects
Bladder cancer -- Health aspects, Diet -- Health aspects, Health, Health aspects
Abstract

In 1996, more than 300,000 new cases of bladder cancer were diagnosed worldwide. Besides tobacco smoking, occupation, and other factors, diet may play a role in causation of this illness. [...]

Published
2001

19. Out-of-hours scintigraphy

Author

Smith Ah and Bury Rf

Subjects
Attitude of Health Personnel, Personnel Staffing and Scheduling, Staffing, Workload, Scintigraphy, Out of hours, Surveys and Questionnaires, medicine, Humans, Radiology, Nuclear Medicine and imaging, Radionuclide Imaging, Response rate (survey), Service (business), medicine.diagnostic_test, business.industry, General Medicine, medicine.disease, England, Current practice, Workforce, Nuclear Medicine Department, Hospital, Medical emergency, Nuclear medicine, business
Abstract

A questionnaire was sent to 221 nuclear medicine departments in the UK asking about their staffing and work patterns. In particular, we wanted to know how many of them offered an on-call service. In those cases where departments wished to offer this service but did not do so, they were asked what was stopping them. Replies were received from 150 departments, a response rate of 68%. Of these, 43 (29%) offered an on-call service, although only 21 (14%) performed ten or more out-of-hours scans in an average year. The examinations most commonly offered were lung scans, localization of gastrointestinal bleeding and renography. In those centres wishing to offer an on-call service but which were unable to do so, limitation of resources was the reason most frequently advanced. Lack of clinical demand was the factor most often quoted by those not wishing to extend their service. The issue of emergency scintigraphy is discussed in the light of these results.

Published
1993

20. The skin and the reticular tissue

Author

Robb Smith Ah

Subjects
Pathology, medicine.medical_specialty, Reticular fiber, Chemistry, Myocardium, Connective tissue, General Medicine, Mononuclear phagocyte system, medicine.anatomical_structure, Gastric Mucosa, Reticular connective tissue, medicine, Humans, Mononuclear Phagocyte System, Skin
Published
2010

21. Hepatic perfusion index

Author

J. Maughan, Gilson P, A. Parkin, P. J. Robinson, Smith Ah, P. J. Finan, Barker Mc, and Avison M

Subjects
Observer Variation, Reproducibility, medicine.diagnostic_test, Perfusion index, business.industry, Reproducibility of Results, Hemodynamics, General Medicine, Blood flow, In Vitro Techniques, Scintigraphy, Imaging phantom, Models, Structural, Technetium Tc 99m Sulfur Colloid, medicine, Humans, Radiology, Nuclear Medicine and imaging, Colorectal Neoplasms, Radionuclide Imaging, Nuclear medicine, business, Perfusion, Technetium-99m, Blood Flow Velocity, Liver Circulation
Abstract

The reproducibility and accuracy of the hepatic perfusion index (HPI) was examined by consideration of in vitro and in vivo factors. A phantom was used to simulate liver blood flow and data acquired on nine gamma cameras. Dynamic hepatic scintigraphy was undertaken on 28 patients at two centres and values obtained for the HPI. Results from the phantom study showed good agreement between the nine cameras and also with the HPI values predicted from the measured phantom flow rates. The results of the patient study indicated a high degree of conformity between observers (r = 0.95, S.E = 0.03) but poorer correlation between the HPI values from the two centres (r = 0.67, S.E. = 0.09). These results imply that centres wishing to use HPI clinically should establish their own range of normality.

Published
1992

25. Contamination of drinking-water by arsenic in Bangladesh : A public health emergency

Author

Smith, AH, Lingas, O, Rahman, M, Smith, AH, Lingas, O, and Rahman, M

Abstract

The contamination of groundwater by arsenic in Bangladesh is the largest poisoning of a population in history, with millions of people exposed. This paper describes the history of the discovery of arsenic in drinking-water in Bangladesh and recommends intervention strategies. Tube-wells were installed to provide 'pure water' to prevent morbidity and mortality from gastrointestinal disease. The water from the millions of tube-wells that were installed was not tested for arsenic contamination. Studies in other countries where the population has had long-term exposure to arsenic in groundwater indicate that 1 in 10 people who drink water containing 500 ╡g of arsenic per litre may ultimately die from cancers caused by arsenic, including lung, bladder and skin cancers. The rapid allocation of funding and prompt expansion of current interventions to address this contamination should be facilitated. The fundamental intervention is the identification and provision of arsenic-free drinking water. Arsenic is rapidly excreted in urine, and for early or mild cases, no specific treatment is required. Community education and participation are essential to ensure that interventions are successful, these should be coupled with follow-up monitoring to confirm that exposure has ended. Taken together with the discovery of arsenic in groundwater in other countries, the experience in Bangladesh shows that groundwater sources throughout the world that are used for drinking-water should be tested for arsenic.

Published
2000

26. Red blood cell transfusion volume and mortality among patients receiving extracorporeal membrane oxygenation.

Author

Smith, Ah, Hardison, Dc, Bridges, Bc, and Pietsch, Jb

Subjects
*EXTRACORPOREAL membrane oxygenation, *ACADEMIC medical centers, *CHI-squared test, *CONFIDENCE intervals, *CONGENITAL heart disease, *EPIDEMIOLOGY, *RED blood cell transfusion, *FISHER exact test, *MEDICAL records, *MORTALITY, *MULTIVARIATE analysis, *U-statistics, *LOGISTIC regression analysis, *DATA analysis, *EQUIPMENT & supplies, *RETROSPECTIVE studies, *DATA analysis software, *DESCRIPTIVE statistics
Abstract

The article discusses a study assessing the association of red blood cell (RBC) transfusion volume and mortality among patients receiving extracorporeal membrane oxygenation (ECMO). ECMO indications are classified to cardiac, non cardiac and extracorporeal cardiopulmonary resuscitation (ECPR). Statistical analysis of the data is presented. The results report an independent increase in the risk of mortality among patients supported with ECMO indications, receiving greater volumes of RBC.

Published
2013
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30. Health effects of arsenic and chromium in drinking water: recent human findings.

Author

Smith AH, Steinmaus CM, Smith, Allan H, and Steinmaus, Craig M

Abstract

Even at high concentrations, arsenic-contaminated water is translucent, tasteless, and odorless. Yet almost every day, studies report a continually increasing plethora of toxic effects that have manifested in exposed populations throughout the world. In this article we focus on recent findings, in particular those associated with major contributions since 2006. Early life exposure, both in utero and in childhood, has been receiving increased attention, and remarkable increases in consequent mortality in young adults have been reported. New studies address the dose-response relationship between drinking-water arsenic concentrations and skin lesions, and new findings have emerged concerning arsenic and cardiovascular disease. We also review the increasing epidemiological evidence that the first step of methylation of inorganic arsenic to monomethylated arsenic (MMA) is actually an activation step rather than the first step in detoxification, as once thought. Hexavalent chromium differs from arsenic in that it discolors water, turning the water yellow at high concentrations. A controversial issue is whether chromium causes cancer when ingested. A recent publication supports the original findings in China of increased cancer mortality in a population where well water turned yellow with chromium. [ABSTRACT FROM AUTHOR]

Published
2009
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31. Arsenic exposure during pregnancy and size at birth: a prospective cohort study in Bangladesh.

Author

Rahman A, Vahter M, Smith AH, Nermell B, Yunus M, El Arifeen S, Persson LA, and Ekström EC

Abstract

The authors evaluated the association of prenatal arsenic exposure with size at birth (birth weight, birth length, head and chest circumferences). This prospective cohort study, based on 1,578 mother-infant pairs, was conducted in Matlab, Bangladesh, in 2002-2003. Arsenic exposure was assessed by analysis of arsenic in urine collected at around gestational weeks 8 and 30. The association of arsenic exposure with size at birth was assessed by linear regression analyses. In analysis over the full range of exposure (6-978 microg/L), no dose-effect association was found with birth size. However, significant negative dose effects were found with birth weight and head and chest circumferences at a low level of arsenic exposure (<100 microg/L in urine). In this range of exposure, birth weight decreased by 1.68 (standard error (SE), 0.62) g for each 1-microg/L increase of arsenic in urine. For head and chest circumferences, the corresponding reductions were 0.05 (SE, 0.03) mm and 0.14 (SE, 0.03) mm per 1 microg/L, respectively. No further negative effects were shown at higher levels of arsenic exposure. The indicated negative effect on birth size at a low level of arsenic exposure warrants further investigation. [ABSTRACT FROM AUTHOR]

Published
2009
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32. Risk assessment in offenders with intellectual disability: a comparison across three levels of security.

Author

Lindsay WR, Hogue TE, Taylor JL, Steptoe L, Mooney P, O'Brien G, Johnston S, and Smith AH

Abstract

In mainstream offender samples, several risk assessments have been evaluated for predictive validity. This study extends this work to male offenders with intellectual disabilities. Participants from high-, medium-, and low-security settings, as well as community settings, were compared on a range of risk assessments. The Violence Risk Appraisal Guide, HCR-20—Historical Scale, the Risk Matrix 2000-C (combined risk), and the Emotional Problems Scales—Internalising discriminated between groups, with participants from high security having higher scores than those in medium security, who had higher scores than those in the community. The Violence Risk Appraisal Guide, all HCR-20 scales, the Short Dynamic Risk Scale, and the Emotional Problems Scales (Internalising and Externalising) showed significant areas under the curve for the prediction of violence. The Static-99 showed a significant area under the curve for the prediction of sexual incidents. The discussion reviews the value of these various scales to intellectual disability services. [ABSTRACT FROM AUTHOR]

Published
2008
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33. High ankle sprains: minimizing the frustration of a prolonged recovery.

Author

Smith AH and Bach BR Jr.

Abstract

High ankle sprains, or syndesmotic injuries, are a distinct entity from the more common inversion ankle sprain. Dorsiflexion of the ankle, external rotation of the leg, or a combination of both can disrupt the syndesmotic ligament complex, including the anterior and posterior tibiofibular ligaments. Diagnostic maneuvers, such as the squeeze test and the external rotation test, plus radiographic findings help make the diagnosis. Less severe sprains can be treated nonoperatively with protected weight bearing, but grade 3 sprains require surgical anatomic reduction of the syndesmotic joint. If misdiagnosed or managed incorrectly, syndesmotic injuries can lead to unfavorable late sequelae. Clinicians should set realistic expectations for a long recovery period and slow return to sports. [ABSTRACT FROM AUTHOR]

Published
2004
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35. Arsenic levels in drinking water and the prevalence of skin lesions in West Bengal, India.

Author

Mazumder, DNG, Haque, R, Ghosh, N, De, BK, Santra, A, Chakraborty, D, and Smith, AH

Abstract

Background.A cross-sectional survey was conducted between April 1995 and March 1996 to investigate arsenic-associated skin lesions of keratosis and hyperpigmentation in West Bengal, India, and to determine their relationship to arsenic water levels. [ABSTRACT FROM PUBLISHER]

Published
1998
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36. Lung and kidney cancer mortality associated with arsenic in drinking water in Córdoba, Argentina.

Author

Hopenhayn-Rich, C, Biggs, ML, Smith, AH, Biggs, M L, and Smith, A H

Abstract

Background: Studies in Taiwan have found dose-response relations between arsenic ingestion from drinking water and cancers of the skin, bladder, lung, kidney and liver. To investigate these associations in another population, we conducted a study in Córdoba, Argentina, which has a well-documented history of arsenic exposure from drinking water.Methods: Mortality from lung, kidney, liver and skin cancers during the period 1986-1991 in Córdoba's 26 counties was investigated, expanding the authors' previous analysis of bladder cancer in the province. Counties were grouped a priori into low, medium and high arsenic exposure categories based on available data. Standardized mortality ratios (SMR) were calculated using all of Argentina as the reference population.Results: We found increasing trends for kidney and lung cancer mortality with arsenic exposure, with the following SMR, for men and women respectively: kidney cancer, 0.87, 1.33, 1.57 and 1.00, 1.36, 1.81; lung cancer, 0.92, 1.54, 1.77 and 1.24, 1.34, 2.16 (in all cases, P < 0.001 in trend test), similar to the previously reported bladder cancer results (0.80, 1.28, 2.14 for men, 1.22, 1.39, 1.81 for women). There was a small positive trend for liver cancer but mortality was increased in all three exposure groups. Skin cancer mortality was elevated for women only in the high exposure group, while men showed a puzzling increase in mortality in the low exposure group.Conclusions: The results add to the evidence that arsenic ingestion increases the risk of lung and kidney cancers. In this study, the association between arsenic and mortality from liver and skin cancers was not clear. [ABSTRACT FROM AUTHOR]

Published
1998
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38. Risk factors in the prevalence of anencephalus and spina bifida in New Zealand

Author

Smith Ah, Borman Gb, and Howard Jk

Subjects
Adult, Male, Risk, congenital, hereditary, and neonatal diseases and abnormalities, Embryology, Pediatrics, medicine.medical_specialty, Health, Toxicology and Mutagenesis, Population, Prevalence, Spina Bifida Occulta, Toxicology, Social class, Sex Factors, Pregnancy, Anencephaly, Epidemiology, Ethnicity, medicine, Humans, Anencephalus, Risk factor, education, education.field_of_study, Spina bifida, business.industry, Infant, Newborn, medicine.disease, nervous system diseases, Parity, Socioeconomic Factors, Female, Epidemiologic Methods, business, Maternal Age, New Zealand, Developmental Biology, Demography
Abstract

This paper presents results from an epidemiological study on the 51 anencephalus and 53 spina bifida cases in the 1978 New Zealand birth cohort. Multiple sources were used in the ascertainment, and the prevalence rates were 0.98 and 1.02 per 1,000 total births, respectively. No association was found with the traditional indicators of the effect of environmental factors: maternal age, social class, nuptiality, month of birth, or estimated month of conception. Males comprised 41% of anencephalus and 36% of spina bifida cases; the prevalence was higher in the non-Maori than in the Maori population. New Zealand-born mothers appear to have a much lower risk of spina bifida, but not anencephaly, than those born in England/Scotland. The rate for the latter population was within the range of a number of UK-based studies. As the bloodstock of New Zealand whites has been predominantly derived from the UK population, and as New Zealand is a low prevalence area, this suggests that the higher risk for these women is likely to be attributable to factors present in their birthplace but absent in New Zealand. These findings provide further evidence that the epidemiologic patterns of anencephalus and spina bifida in low-prevalence areas are at variance with those in high-prevalence areas, such as the United Kingdom. They also support the hypothesis that the contrast in rates between high- and low-prevalence areas is a reflection of the impact of environmental factors in high-prevalence areas on the "background" or baseline frequency of anencephalus and spina bifida found in low-prevalence areas.

Published
1986

39. Delay of response in the perception of slant and shape

Author

Smith Ah

Subjects
Visual perception, media_common.quotation_subject, General Medicine, Form Perception, Form perception, Perception, Reaction Time, Visual Perception, Humans, Psychology, Vision, Ocular, media_common, Cognitive psychology
Published
1964

42. Attempt to demonstrate an in vivo effect of mianserin hydrochloride on erythrocyte Na+-K+-ATPase activity and cyclic AMP concentration.

Author

Naylor, GS, Buckley, DE, Boardman, LJ, Smith, AH, and Moody, JP

Abstract

1. There is evidence that erythrocyte Na+-K+-ATPase activity and erythrocyte cyclic AMP change on recovery from a depressive illness. Mianserin is a recently introduced antidepressant but its mode of action is unknown. The present study was therefore designed to investigate in vivo the effect of mianserin on erythrocyte Na+-K+- ATPase and cyclic AMP. 2. Biochemical estimations were made on blood from depressed patients before beginning either mianserin or matched placebo treatment, after 1 week, and again after 2 weeks' treatment. 3. Neither the erythrocyte Na+-K+-ATPase, nor the erythrocyte cyclic AMP concentration, changed significantly in either the mianserin- or the placebo-treated group. 4. The study sheds no light on the possible mechanism of action of mianserin. [ABSTRACT FROM AUTHOR]

Published
1978
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43. Apparent distance in monocular slant and shape judgments

Author

Smith Ah

Subjects
Form Perception, Monocular, business.industry, Angular distance, Distance Perception, Visual Perception, Humans, Experimental and Cognitive Psychology, Computer vision, Artificial intelligence, business, Sensory Systems, Mathematics
Published
1968

44. RELATION OF SLANT AND SHAPE JUDGMENTS IN REDUCED VIEWING

Author

Smith Ah

Subjects
Form Perception, Judgment, Visual perception, Form perception, Relation (database), Visual Perception, Humans, General Medicine, Psychology, Binocular vision, Monocular vision, Cognitive psychology
Published
1964

45. INTERACTION OF FORM AND EXPOSURE TIME IN THE PERCEPTION OF SLANT

Author

Smith Ah

Subjects
genetic structures, media_common.quotation_subject, 05 social sciences, Experimental and Cognitive Psychology, Space perception, 030229 sport sciences, 050105 experimental psychology, Sensory Systems, Form Perception, 03 medical and health sciences, 0302 clinical medicine, Form perception, Perception, Space Perception, Humans, 0501 psychology and cognitive sciences, Psychology, media_common, Cognitive psychology
Abstract

Groups of 24 Os estimated the slant of a circle and a rectangle (Groups I, II, and III) or a circle and a square (Group IV) by setting a tilt-rod. The forms were viewed at 45° slant, monocularly and binocularly, with fixed head, under reduced conditions. Exposure durations were: for Groups I, II, and IV, 5, 4, 3, 2, and 1 sec., imposed in descending order; and for Group III, five 3-sec. exposures. Groups I and III left the tilt-rod at the response setting, and Groups II and IV returned it to vertical, after each response. With reduced exposure, over-all estimates of slant decreased for the response setting (Group I), but decreased less (Group IV), or did not change significantly Group II) for the vertical setting. The difference between the estimates for the circle and rectangle or square increased with reduced exposure time due mainly to decrement for the angular forms. The discussion relates the over-all result to an anchor effect of tilt-rod position, and the trend difference for form to differential salience of projective outline distortion and convergence.

Published
1965

46. Development of nested polymerase chain reaction detection of Mycosphaerella spp. and its application to the study of leaf disease in Eucalyptus plantations

Author

Glen, M, Smith, AH, Langrell, SRH, Mohammed, CL, Glen, M, Smith, AH, Langrell, SRH, and Mohammed, CL

Abstract

Mycosphaerella leaf disease (MLD) is a serious disease of two of the major eucalypt species grown in temperate regions worldwide, Eucalyptus globulus and E. nitens. More than 30 species of Mycosphaerella have been reported on eucalypts worldwide. Accurate, rapid, and early discrimination of Mycosphaerella spp. causing crown damage to E globulus and E. nitens will assist the development of sustainable management strategies. This study describes the development, and incorporation in a nested polymerase chain reaction (PCR) approach, of specific primers for the detection and identification of Mycosphaerella spp. commonly reported from leaf lesions of E. globulus and E. nitens in Australia. Primer design was assisted by sequence alignment and phylogenetic analysis of 165 nonredundant sequences from the nuclear ribosomal DNA internal transcribed spacer regions of Mycosphaerella and related species. Phylogenetic analysis revealed very high sequence similarity for two taxon groups, Mycosphaerella grandis and M. parva, and M. vespa, M. ambiphylla, and M. molleriana, and primers were designed to differentiate each of the two groups. Three other species, M. cryptica, M. nubilosa, and M. tasmaniensis, were distinct and distinguished by species-specific primers. In double-blind trials, the detection test accurately and rapidly identified Mycosphaerella spp. in cultures and discriminated against other pathogens that co-occur in or on Eucalyptus leaves, thereby verifying its reliability. The detection test has an internal amplification control in the first-round PCR with fungal-specific primers to raise confidence in test results, particularly to highlight negative results due to PCR inhibition. When applied to DNA extracted from leaf or stem samples either as multiple or single lesions, it detected and identified up to five Mycosphaerella spp. or taxon groups in both positively identified and in young (putative) MLD lesions. The samples were 20 mm(2) or larger in surface area an

47. Anatomical and histochemical defence responses induced in juvenile leaves of Eucalyptus globulus and Eucalyptus nitens by Mycosphaerella infection

Author

Smith, AH, Gill, WM, Pinkard, EA, Mohammed, CL, Smith, AH, Gill, WM, Pinkard, EA, and Mohammed, CL

Abstract

The responses of juvenile leaves of two Eucalyptus species, with contrasting susceptibility to infection by Mycosphaerella leaf disease, were compared. The anatomical changes, accumulation of phenolics, suberin, lignin and anthocyanin and the retention of chlorophyll were studied in leaf lesions of varying developmental stages caused by species of Mycosphaerella. Enhanced resistance of Eucalyptus nitens in southern Australia was attributed to the formation of an effective lignified and suberized necrophylactic periderm, to restrict pathogen spread. Leaves of E. nitens contained isobilateral palisade which resulted in both abaxial and adaxial cell division and the initiation of a strong reinforced cellular zone from an early lesion stage. Eucalyptus globulus formed a slower, distorted necrophylactic periderm through hypertrophic changes to existing mesophyll and limited cell divisions of the single adaxial palisade layer. Deposits of lignin and suberin did not occur until later in lesion development, which were not effective in preventing further disease development. From this study it is hypothesized that tolerance of eucalypts to Mycosphaerella pathogens may be associated with constitutive mesophyll density.

48. Development of nested polymerase chain reaction detection of Mycosphaerella spp. and its application to the study of leaf disease in Eucalyptus plantations

Author

Glen, M, Smith, AH, Langrell, SRH, Mohammed, CL, Glen, M, Smith, AH, Langrell, SRH, and Mohammed, CL

Abstract

Mycosphaerella leaf disease (MLD) is a serious disease of two of the major eucalypt species grown in temperate regions worldwide, Eucalyptus globulus and E. nitens. More than 30 species of Mycosphaerella have been reported on eucalypts worldwide. Accurate, rapid, and early discrimination of Mycosphaerella spp. causing crown damage to E globulus and E. nitens will assist the development of sustainable management strategies. This study describes the development, and incorporation in a nested polymerase chain reaction (PCR) approach, of specific primers for the detection and identification of Mycosphaerella spp. commonly reported from leaf lesions of E. globulus and E. nitens in Australia. Primer design was assisted by sequence alignment and phylogenetic analysis of 165 nonredundant sequences from the nuclear ribosomal DNA internal transcribed spacer regions of Mycosphaerella and related species. Phylogenetic analysis revealed very high sequence similarity for two taxon groups, Mycosphaerella grandis and M. parva, and M. vespa, M. ambiphylla, and M. molleriana, and primers were designed to differentiate each of the two groups. Three other species, M. cryptica, M. nubilosa, and M. tasmaniensis, were distinct and distinguished by species-specific primers. In double-blind trials, the detection test accurately and rapidly identified Mycosphaerella spp. in cultures and discriminated against other pathogens that co-occur in or on Eucalyptus leaves, thereby verifying its reliability. The detection test has an internal amplification control in the first-round PCR with fungal-specific primers to raise confidence in test results, particularly to highlight negative results due to PCR inhibition. When applied to DNA extracted from leaf or stem samples either as multiple or single lesions, it detected and identified up to five Mycosphaerella spp. or taxon groups in both positively identified and in young (putative) MLD lesions. The samples were 20 mm(2) or larger in surface area an

49. Development of nested polymerase chain reaction detection of Mycosphaerella spp. and its application to the study of leaf disease in Eucalyptus plantations

Author

Glen, M, Smith, AH, Langrell, SRH, Mohammed, CL, Glen, M, Smith, AH, Langrell, SRH, and Mohammed, CL

Abstract

Mycosphaerella leaf disease (MLD) is a serious disease of two of the major eucalypt species grown in temperate regions worldwide, Eucalyptus globulus and E. nitens. More than 30 species of Mycosphaerella have been reported on eucalypts worldwide. Accurate, rapid, and early discrimination of Mycosphaerella spp. causing crown damage to E globulus and E. nitens will assist the development of sustainable management strategies. This study describes the development, and incorporation in a nested polymerase chain reaction (PCR) approach, of specific primers for the detection and identification of Mycosphaerella spp. commonly reported from leaf lesions of E. globulus and E. nitens in Australia. Primer design was assisted by sequence alignment and phylogenetic analysis of 165 nonredundant sequences from the nuclear ribosomal DNA internal transcribed spacer regions of Mycosphaerella and related species. Phylogenetic analysis revealed very high sequence similarity for two taxon groups, Mycosphaerella grandis and M. parva, and M. vespa, M. ambiphylla, and M. molleriana, and primers were designed to differentiate each of the two groups. Three other species, M. cryptica, M. nubilosa, and M. tasmaniensis, were distinct and distinguished by species-specific primers. In double-blind trials, the detection test accurately and rapidly identified Mycosphaerella spp. in cultures and discriminated against other pathogens that co-occur in or on Eucalyptus leaves, thereby verifying its reliability. The detection test has an internal amplification control in the first-round PCR with fungal-specific primers to raise confidence in test results, particularly to highlight negative results due to PCR inhibition. When applied to DNA extracted from leaf or stem samples either as multiple or single lesions, it detected and identified up to five Mycosphaerella spp. or taxon groups in both positively identified and in young (putative) MLD lesions. The samples were 20 mm(2) or larger in surface area an

50. Anatomical and histochemical defence responses induced in juvenile leaves of Eucalyptus globulus and Eucalyptus nitens by Mycosphaerella infection

Author

Smith, AH, Gill, WM, Pinkard, EA, Mohammed, CL, Smith, AH, Gill, WM, Pinkard, EA, and Mohammed, CL

Abstract

The responses of juvenile leaves of two Eucalyptus species, with contrasting susceptibility to infection by Mycosphaerella leaf disease, were compared. The anatomical changes, accumulation of phenolics, suberin, lignin and anthocyanin and the retention of chlorophyll were studied in leaf lesions of varying developmental stages caused by species of Mycosphaerella. Enhanced resistance of Eucalyptus nitens in southern Australia was attributed to the formation of an effective lignified and suberized necrophylactic periderm, to restrict pathogen spread. Leaves of E. nitens contained isobilateral palisade which resulted in both abaxial and adaxial cell division and the initiation of a strong reinforced cellular zone from an early lesion stage. Eucalyptus globulus formed a slower, distorted necrophylactic periderm through hypertrophic changes to existing mesophyll and limited cell divisions of the single adaxial palisade layer. Deposits of lignin and suberin did not occur until later in lesion development, which were not effective in preventing further disease development. From this study it is hypothesized that tolerance of eucalypts to Mycosphaerella pathogens may be associated with constitutive mesophyll density.

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