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Stephens JC, Reich DE, Goldstein DB, Shin HD, Smith MW, Carrington M, Winkler C, Huttley GA, Allikmets R, Schriml L, Gerrard B, Malasky M, Ramos MD, Morlot S, Tzetis M, Oddoux C, di Giovine FS, Nasioulas G, Chandler D, Aseev M, Hanson M, Kalaydjieva L, Glavac D, Gasparini P, Kanavakis E, Claustres M, Kambouris M, Ostrer H, Duff G, Baranov V, Sibul H, Metspalu A, Goldman D, Martin N, Duffy D, Schmidtke J, Estivill X, O'Brien SJ, Dean M. Dating the origin of the CCR5-Delta32 AIDS-resistance allele by the coalescence of haplotypes. Am J Hum Genet 1998; 62:1507-15. [PMID: 9585595 PMCID: PMC1377146 DOI: 10.1086/301867] [Citation(s) in RCA: 343] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The CCR5-Delta32 deletion obliterates the CCR5 chemokine and the human immunodeficiency virus (HIV)-1 coreceptor on lymphoid cells, leading to strong resistance against HIV-1 infection and AIDS. A genotype survey of 4,166 individuals revealed a cline of CCR5-Delta32 allele frequencies of 0%-14% across Eurasia, whereas the variant is absent among native African, American Indian, and East Asian ethnic groups. Haplotype analysis of 192 Caucasian chromosomes revealed strong linkage disequilibrium between CCR5 and two microsatellite loci. By use of coalescence theory to interpret modern haplotype genealogy, we estimate the origin of the CCR5-Delta32-containing ancestral haplotype to be approximately 700 years ago, with an estimated range of 275-1,875 years. The geographic cline of CCR5-Delta32 frequencies and its recent emergence are consistent with a historic strong selective event (e.g. , an epidemic of a pathogen that, like HIV-1, utilizes CCR5), driving its frequency upward in ancestral Caucasian populations.
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Whyte M, Hubbard R, Meliconi R, Whidborne M, Eaton V, Bingle C, Timms J, Duff G, Facchini A, Pacilli A, Fabbri M, Hall I, Britton J, Johnston I, Di Giovine F. Increased risk of fibrosing alveolitis associated with interleukin-1 receptor antagonist and tumor necrosis factor-alpha gene polymorphisms. Am J Respir Crit Care Med 2000; 162:755-8. [PMID: 10934117 DOI: 10.1164/ajrccm.162.2.9909053] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Fibrosing alveolitis (FA) is characterized by persistent inflammation and elevated production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta), and interleukin-1 receptor antagonist (IL-1ra) in the lung. Single base variations at position +2018 in the IL-1ra gene (IL-1RN) and position -308 in the TNF-alpha gene (TNF-A) are overrepresented in other chronic inflammatory disease populations. We have tested the hypothesis that predisposition to FA may also be influenced by these polymorphisms by genotyping 88 cases and matched controls from England and 61 cases and 103 unmatched controls from Italy. The rarer allele for IL-1RN and TNF-A was designated allele 2 in each case. For IL-1RN allele 2, in the English group, the relative odds of FA were increased in homozygous subjects by an odds ratio (OR) of 10.2 (95% confidence intervals [CI], 1.26 to 81.4; p = 0.03) and for carriers by an OR of 1.85 (95% CI, 0.94 to 3.63; p = 0.075). In the Italian population, the risk of FA was increased, in IL-1RN allele 2 homozygotes (OR, 2.54; 95% CI, 0.68 to 9.50; p = 0.2) and in carriers (OR 2.40; 95% CI, 1.26 to 4.60; p = 0.008). Carriage of TNF-A allele 2 was also associated with increased risk of FA in the English (OR, 1.85; 95% CI, 0.94 to 3.63; p = 0.075) and Italian (OR, 2.50; 95% CI, 1.14 to 5.47; p = 0.022) populations. These data suggest IL-1RN (+2018) allele 2 and TNF-A (-308) allele 2 confer increased risk of developing FA and, therefore, that unopposed IL-1beta and/or excessive TNF-alpha may play a pathophysiologic role in this condition.
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118 |
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Genevay S, Di Giovine FS, Perneger TV, Silvestri T, Stingelin S, Duff G, Guerne PA. Association of interleukin-4 and interleukin-1B gene variants with Larsen score progression in rheumatoid arthritis. ARTHRITIS AND RHEUMATISM 2002; 47:303-9. [PMID: 12115161 DOI: 10.1002/art.10394] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To perform a genetic association study using markers in the interleukin-1 (IL-1) gene cluster and the IL-4/IL-4 receptor system genes, seeking evidence for involvement in the onset or the erosive outcome of rheumatoid arthritis (RA). METHODS We tested the allelic distribution of IL-1A (+4845), IL-1B (-511), IL-1B (+3954), IL-1RN (+2018), IL-4 variable number of tandem repeat (VNTR), and IL-4R (+1902) in 233 patients with RA, 99 with polymyalgia rheumatica, and 148 ethnically matched controls. We analyzed the frequency of these gene variants in respect to presence of disease, but also to the degree of radiologic erosions (Larsen score) as a function of disease duration in 157 patients who had available radiographs of both hands. RESULTS None of the 6 genetic polymorphisms was significantly different in frequency between RA patients and healthy controls or patients with polymyalgia rheumatica. Among RA patients, the rarer (#2) alleles of IL-4 VNTR and IL-1B (-511) were both associated with a milder Larsen score progression: The slope of Larsen progression in the rare allele groups diverged significantly from those of the frequent allele groups after approximately 20 years of disease duration (P < 0.001). CONCLUSION None of the markers tested were shown to be associated with increased or decreased risk of RA. The rarer alleles of IL-4 VNTR and IL-1B (-511) appear to be associated with a less severe course in RA of long duration.
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Anderson N, Boswell O, Duff G. Prenatal sonography for the detection of fetal anomalies: results of a prospective study and comparison with prior series. AJR Am J Roentgenol 1995; 165:943-50. [PMID: 7676997 DOI: 10.2214/ajr.165.4.7676997] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Reported rates of sonographic detection of fetal anomaly vary widely. The purpose of our study was to determine how well we were detecting fetal anomaly in our region and to compare our results with published series using standardized criteria. SUBJECTS AND METHODS Over a 2-year period, we compared the reports of sonographic studies done in 7880 pregnancies at 16-20 weeks' gestation with all pregnancy outcomes established by medical records and pathologic results of the infants, whether born alive or dead. Fetal anomaly was defined as any structural anomaly except for those specifically excluded. We compared our results, expressed as percentage of anomalies found and anomalies found per 1000 pregnancies screened, with those of published studies, modifying published figures where necessary to compensate for our defined exclusion criteria. RESULTS At postnatal examination, we found 157 anomalies in 144 babies who had prenatal sonography at 16-20 weeks' gestation. We detected 93 anomalies (60%) in 84 fetuses, leading to termination of pregnancy in 42 cases (50% of anomalous fetuses). The prevalence of fetal anomaly in our population was 19.8 anomalies per 1000 pregnancies screened. We detected 11.8 anomalies per 1000 screened, leading to termination of 5.3 pregnancies per 1000 screened. Our success rate for fetal anomaly detection ranged from 92% for CNS anomalies to 31% for cardiac anomalies and 25% for craniofacial anomalies. There were fewer babies born with a major malformation in the group whose anomalies were detected prenatally (21%) than in the group whose anomalies were not detected (58%). By comparison, in prior series, prevalence of anomalies varied from 5.67 to 25.95 per-11000 screened; anomaly detection varied from 16.6% to 74.4%; detection rate varied from 3.08 to 11.03 per 1000 screened. There was no correlation between the percentage and per 1000 detection rates. Thus, the RADIUS and Helsinki trials had similar detection rates per 1000, but more than a twofold difference in percentage detection rate. Similarly, the percentage success rate in studies could be the same, but the detection rate per 1000 different threshold. There was a similar lack of correlation for rates of pregnancy termination. All series except for the RADIUS study reported a reduction in the rate of adverse outcome if the anomalies were detected prenatally. CONCLUSION Our rate of detection of fetal anomaly is satisfactory for most organ systems but remains poor for cardiac, skeletal, and craniofacial anomalies. The relative ranking of the success of fetal anomaly detection in prior studies depends on whether the detection rate is reported as a percentage or as the number of anomalies detected per 1000 screened. Our results compare favorably with those reported in other series.
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Comparative Study |
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53 |
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Yanni G, Whelan A, Feighery C, Quinlan W, Symons J, Duff G, Bresnihan B. Contrasting levels of in vitro cytokine production by rheumatoid synovial tissues demonstrating different patterns of mononuclear cell infiltration. Clin Exp Immunol 1993; 93:387-95. [PMID: 8370165 PMCID: PMC1554917 DOI: 10.1111/j.1365-2249.1993.tb08190.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Synovial membrane samples obtained at knee arthroplasty from 22 patients with rheumatoid arthritis (RA) were characterized histologically. Two groups were identified. Tissue samples from 15 patients demonstrated multiple focal lymphoid aggregates of mononuclear cells (group A). Samples from the remaining seven patients demonstrated diffuse mononuclear cell infiltration (group B). Samples of each synovial membrane (0.25 g) were cultured for cytokine production. The highest levels of IL-1 beta and IL-6 were produced by group A tissues: 19.1 +/- 19.6 ng/ml IL-1 beta (mean +/- s.d.) and 264.4 +/- 301.9 ng/ml IL-6, versus 3.8 +/- 6.6 ng/ml and 54.7 +/- 42.6 ng/ml respectively. Small quantities of IL-2 and IL-4 were measured in both groups: the levels of IL-2 in group A cultures were highest (P = 0.04). Moreover, using MoAbs, the most intense cytokine staining in the tissues was detected in group A. Similar total numbers of each cell subpopulation and similar quantities of immunoglobulin and rheumatoid factor synthesis were measured in both groups. It is suggested that the presence of multiple focal lymphoid aggregates associated with higher levels of cytokine production observed in group A represent a greater degree of immunological activation, and may represent a subgroup of patients with a greater potential for articular destruction.
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Ierodiaconou D, Laurenson L, Leblanc M, Stagnitti F, Duff G, Salzman S, Versace V. The consequences of land use change on nutrient exports: a regional scale assessment in south-west Victoria, Australia. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2005; 74:305-316. [PMID: 15737455 DOI: 10.1016/j.jenvman.2004.09.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2003] [Revised: 09/15/2004] [Accepted: 09/18/2004] [Indexed: 05/24/2023]
Abstract
Estimation of nutrient load production based on multi-temporal remotely sensed land use data for the Glenelg-Hopkins region in south-west Victoria, Australia, is discussed. Changes in land use were mapped using archived Landsat data and computerised classification techniques. Land use change has been rapid in recent history with 16% of the region transformed in the last 22 years. Total nitrogen and phosphorus loads were estimated using an export coefficient model. The analysis demonstrates an increase in modelled nitrogen and phosphorus loadings from 1980 to 2002. Whilst such increases were suspected from past anecdotal and ad-hoc evidence, our modelling estimated the magnitude of such increases and thus demonstrated the enormous potential of using remote sensing and GIS for monitoring regional scale environmental processes.
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Comparative Study |
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29 |
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Wanat M, Logan M, Hirst JA, Vicary C, Lee JJ, Perera R, Tracey I, Duff G, Tufano P, Fanshawe T, Mwandigha L, Nicholson BD, Tonkin-Crine S, Hobbs R. Perceptions on undertaking regular asymptomatic self-testing for COVID-19 using lateral flow tests: a qualitative study of university students and staff. BMJ Open 2021; 11:e053850. [PMID: 34475190 PMCID: PMC8413471 DOI: 10.1136/bmjopen-2021-053850] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
OBJECTIVES Successful implementation of asymptomatic testing programmes using lateral flow tests (LFTs) depends on several factors, including feasibility, acceptability and how people act on test results. We aimed to examine experiences of university students and staff of regular asymptomatic self-testing using LFTs, and their subsequent behaviours. DESIGN AND SETTING A qualitative study using semistructured remote interviews and qualitative survey responses, which were analysed thematically. PARTICIPANTS People who were participating in weekly testing feasibility study, between October 2020 and January 2021, at the University of Oxford. RESULTS We interviewed 18 and surveyed 214 participants. Participants were motivated to regularly self-test as they wanted to know whether or not they were infected with SARS-CoV-2. Most reported that a negative test result did not change their behaviour, but it did provide them with reassurance to engage with permitted activities. In contrast, some participants reported making decisions about visiting other people because they felt reassured by a negative test result. Participants valued the training but some still doubted their ability to carry out the test. Participants were concerned about safety of attending test sites with lots of people and reported home testing was most convenient. CONCLUSIONS Clear messages highlighting the benefits of regular testing for family, friends and society in identifying asymptomatic cases are needed. This should be coupled with transparent communication about the accuracy of LFTs and how to act on either a positive or negative result. Concerns about safety, convenience of testing and ability to do tests need to be addressed to ensure successful scaling up of asymptomatic testing.
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research-article |
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Eamus D, Myers B, Duff G, Williams D. Seasonal changes in photosynthesis of eight savanna tree species. TREE PHYSIOLOGY 1999; 19:665-671. [PMID: 12651322 DOI: 10.1093/treephys/19.10.665] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Seasonal variations in carbon assimilation of eight tree species of a north Australian tropical savanna were examined over two wet seasons and one dry season (18 months). Assimilation rates (A) in the two evergreen species, Eucalyptus tetrodonta F. Muell. and E. miniata A. Cunn. ex Schauer, were high throughout the study although there was a 10-20% decline in the dry season compared with the wet season. The three semi-deciduous species (Erythrophleum chlorostachys (F. Muell.) Baillon, Eucalyptus clavigera A. Cunn. ex Schauer, and Xanthostemon paradoxus F. Muell.) showed a 25-75% decline in A in the dry season compared with the wet season, and the deciduous species (Terminalia ferdinandiana Excell, Planchonia careya (F. Muell.) Kunth, and Cochlospermum fraseri Planchon) were leafless for several months in the dry season. Generally, the ratio of intercellular CO(2) concentration to ambient CO(2) concentration (C(i):C(a)) was larger in the wet season than in the dry season, indicating a smaller stomatal limitation of photosynthesis in the wet season compared with the dry season. In all species, the C(i):C(a) ratio and A were essentially independent of leaf-to-air vapor pressure difference (LAVPD) during the wet season, but both parameters generally declined with increasing LAVPD in the dry season. The slope of the positive correlation between A and transpiration rate (E) was less in the wet season than in the dry season. There was no evidence that high E inhibited A. Instantaneous transpiration efficiency was lowest in the wet season and highest during the dry season. Nitrogen-use efficiency (NUE) was higher in the wet season than in the dry season because the decline in A in the dry season was proportionally larger than the decline in foliar nitrogen content. In the wet season, evergreen species exhibited higher NUE than semi-deciduous and deciduous species. In all species, A was linearly correlated with specific leaf area (SLA) and foliar N content. Foliar N content increased with increasing SLA. All species showed a decline in midday leaf water potential as the dry season progressed. Dry season midday water potentials were lowest in semi-deciduous species and highest in the deciduous species, with evergreen species exhibiting intermediate values.
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Historical Article |
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Burn J, Duff G, Holtzman N. Three views of genetics: the enthusiast, the visionary, and the sceptic. Interview by Tessa Richards. BMJ (CLINICAL RESEARCH ED.) 2001; 322:1016. [PMID: 11325760 PMCID: PMC1120178 DOI: 10.1136/bmj.322.7293.1016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Interview |
24 |
11 |
12
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Hirst JA, Logan M, Fanshawe TR, Mwandigha L, Wanat M, Vicary C, Perera R, Tonkin-Crine S, Lee JJ, Tracey I, Duff G, Tufano P, Besharov M, Tarassenko L, Nicholson BD, Hobbs FDR. Feasibility and Acceptability of Community Coronavirus Disease 2019 Testing Strategies (FACTS) in a University Setting. Open Forum Infect Dis 2021; 8:ofab495. [PMID: 34904117 PMCID: PMC8515264 DOI: 10.1093/ofid/ofab495] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/24/2021] [Indexed: 12/30/2022] Open
Abstract
Background During the coronavirus disease 2019 (COVID-19) pandemic in 2020, the UK government began a mass severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing program. This study aimed to determine the feasibility and acceptability of organized regular self-testing for SARS-CoV-2. Methods This was a mixed-methods observational cohort study in asymptomatic students and staff at University of Oxford, who performed SARS-CoV-2 antigen lateral flow self-testing. Data on uptake and adherence, acceptability, and test interpretation were collected via a smartphone app, an online survey, and qualitative interviews. Results Across 3 main sites, 551 participants (25% of those invited) performed 2728 tests during a follow-up of 5.6 weeks; 447 participants (81%) completed at least 2 tests, and 340 (62%) completed at least 4. The survey, completed by 214 participants (39%), found that 98% of people were confident to self-test and believed self-testing to be beneficial. Acceptability of self-testing was high, with 91% of ratings being acceptable or very acceptable. A total of 2711 (99.4%) test results were negative, 9 were positive, and 8 were inconclusive. Results from 18 qualitative interviews with students and staff revealed that participants valued regular testing, but there were concerns about test accuracy that impacted uptake and adherence. Conclusions This is the first study to assess feasibility and acceptability of regular SARS-CoV-2 self-testing. It provides evidence to inform recruitment for, adherence to, and acceptability of regular SARS-CoV-2 self-testing programs for asymptomatic individuals using lateral flow tests. We found that self-testing is acceptable and people were able to interpret results accurately.
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Medani M, Kelly N, Samaha G, Duff G, Healy V, Mulcahy E, Condon E, Waldron D, Saunders J, Coffey JC. An appraisal of lymph node ratio in colon and rectal cancer: not one size fits all. Int J Colorectal Dis 2013; 28:1377-84. [PMID: 23715847 DOI: 10.1007/s00384-013-1707-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/24/2013] [Indexed: 02/08/2023]
Abstract
BACKGROUND Lymph node ratio (LNR) is increasingly accepted as a useful prognostic indicator in colorectal cancer. However, variations in methodology, statistical stringency and cohort composition has led to inconsistency in respect of the optimally prognostic LNR. OBJECTIVE The aim was to apply a robust regression-based analysis to generate and appraise LNRs optimally prognostic for colon and rectal cancer, both separately and in combination. METHODS LNR was established for all patients undergoing either a colonic (n = 379) or rectal (n = 160) cancer resection with curative intent. The optimal LNR associated with disease-free and overall survival were established using a classification and regression tree technique. This process was repeated separately for patients who underwent either colonic or rectal resection and for the combined cohort. Survival associated with differing LNR was estimated using the Kaplan-Meier method and compared using a log-rank test. Relationships between LNR, disease-free survival (DFS) and overall survival (OS) were further characterised using Cox regression analysis. All statistical analyses were conducted in the R programming environment, with statistical significance was taken at a level of p < 0.05. RESULTS Optimal LNRs differed between each cohort, when either overall or disease-free survival was considered. LNRs generated from combined cohorts also differed from those generated by individual cohorts. In relation to DFS, LNR values were obtained and included 0.18 for the colon cancer cohort and 0.19 for the rectal and combined colorectal cancer cohorts. In relation to OS, multiple LNR values were obtained for colon and combined cohorts; however, an optimal LNR was not evident in the rectal cancer cohort. Survival patterns according to LNR closely resembled those associated with standard nodal staging. CONCLUSION Application of a data-driven approach based on recursive partitioning generates differing lymph node ratios for colon, rectal and combined colorectal cohorts. In each cohort, LNR was similarly prognostic to standard nodal staging in respect to overall and disease-free survival. Overall survival was associated with a multiplicity of LNR values, whilst disease-free survival was associated with a single LNR only. The paper demonstrates the merits of utilising a data-driven approach to determining lymph node ratios from specific patient cohorts. Utilising such an approach enabled the generation of those LNRs that were most associated with particular survival trends in relation to overall and disease-free survival. These differed markedly for colon cancer, rectal cancer and combined cohorts. In general, the survival patterns associated with LNRs generated were similar to those observed with standard nodal staging.
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Goodfellow J, Eamus D, Duff G. Diurnal and seasonal changes in the impact of CO(2) enrichment on assimilation, stomatal conductance and growth in a long-term study of Mangifera indica in the wet-dry tropics of Australia. TREE PHYSIOLOGY 1997; 17:291-299. [PMID: 14759852 DOI: 10.1093/treephys/17.5.291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We studied assimilation, stomatal conductance and growth of Mangifera indica L. saplings during long-term exposure to a CO(2)-enriched atmosphere in the seasonally wet-dry tropics of northern Australia. Grafted saplings of M. indica were planted in the ground in four air-conditioned, sunlit, plastic-covered chambers and exposed to CO(2) at the ambient or an elevated (700 micro mol mol(-1)) concentration for 28 months. Light-saturating assimilation (A(max)), stomatal conductance (g(s)), apparent quantum yield (phi), biomass and leaf area were measured periodically. After 28 months, the CO(2) treatments were changed in all four chambers from ambient to the elevated concentration or vice versa, and A(max) and g(s) were remeasured during a two-week exposure to the new regime. Throughout the 28-month period of exposure, A(max) and apparent quantum yield of leaves in the elevated CO(2) treatment were enhanced, whereas stomatal conductance and stomatal density of leaves were reduced. The relative impacts of atmospheric CO(2) enrichment on assimilation and stomatal conductance were significantly larger in the dry season than in the wet season. Total tree biomass was substantially increased in response to atmospheric CO(2) enrichment throughout the experimental period, but total canopy area did not differ between CO(2) treatments at either the first or the last harvest. During the two-week period following the change in CO(2) concentration, A(max) of plants grown in ambient air but measured in CO(2)-enriched air was significantly larger than that of trees grown and measured in CO(2)-enriched air. There was no difference in A(max) between trees grown and measured in ambient air compared to trees grown in CO(2)-enriched air but measured in ambient air. No evidence of down-regulation of assimilation in response to atmospheric CO(2) enrichment was observed when rates of assimilation were compared at a common intercellular CO(2) concentration. Reduced stomatal conductance in response to atmospheric CO(2) enrichment was attributed to a decline in both stomatal aperture and stomatal density.
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Comment |
34 |
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Kornman K, Duff G, Reilly P. Re: A critical assessment of interleukin-1 (IL-1) genotyping when used in a genetic susceptibility test for severe chronic periodontitis. Greenstein G, Hart TC (2002;73:231-247). J Periodontol 2002; 73:1553-6; author reply 1556-8. [PMID: 12546107 DOI: 10.1902/jop.2002.73.12.1553] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Comment |
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Hügli RV, Duff G, O'Conchuir B, Mengotti E, Rodríguez AF, Nolting F, Heyderman LJ, Braun HB. Artificial kagome spin ice: dimensional reduction, avalanche control and emergent magnetic monopoles. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2012; 370:5767-5782. [PMID: 23166379 DOI: 10.1098/rsta.2011.0538] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Artificial spin-ice systems consisting of nanolithographic arrays of isolated nanomagnets are model systems for the study of frustration-induced phenomena. We have recently demonstrated that monopoles and Dirac strings can be directly observed via synchrotron-based photoemission electron microscopy, where the magnetic state of individual nanoislands can be imaged in real space. These experimental results of Dirac string formation are in excellent agreement with Monte Carlo simulations of the hysteresis of an array of dipoles situated on a kagome lattice with randomized switching fields. This formation of one-dimensional avalanches in a two-dimensional system is in sharp contrast to disordered thin films, where avalanches associated with magnetization reversal are two-dimensional. The self-organized restriction of avalanches to one dimension provides an example of dimensional reduction due to frustration. We give simple explanations for the origin of this dimensional reduction and discuss the disorder dependence of these avalanches. We conclude with the explicit demonstration of how these avalanches can be controlled via locally modified anisotropies. Such a controlled start and stop of avalanches will have potential applications in data storage and information processing.
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Hutchinson C, Milte R, Stanley M, Duff G, Ratcliffe J. Using discrete choice experiments to elicit the service preferences of people with mild intellectual disability: An exploratory study. HEALTH & SOCIAL CARE IN THE COMMUNITY 2022; 30:e1396-e1405. [PMID: 34418195 DOI: 10.1111/hsc.13547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/14/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
The National Disability Insurance Scheme (NDIS) in Australia and other similar international movements towards consumer direction have highlighted the importance of including consumers to ensure their service preferences are operationalised. Discrete Choice Experiments (DCEs) are an established method to quantify consumer preferences. The feasibility of using DCEs with people with intellectual disability is largely untested. Consenting participants eligible for disability support services (n = 18) participated in the mixed methods exploratory study. The DCE comprised a series of choices between two hypothetical service providers offering a combination of services relating to social and economic participation (e.g. support with finding and keeping a job), with four levels of service (no service, online support, group support, one to one support). Pictographs and simplified English were used to represent the hypothetical services and levels and a 'think aloud' protocol adopted. Most participants (N = 16, 89%) completed the DCE task. The findings from the think aloud task indicated that some participants were weighing up the options and making decisions based on their goals and personal preferences. However, other participants did not focus on all presented attributes and levels when making a decision; a common 'short-cut' heuristic also observed in DCE tasks with general population participants. Further research including investigating other DCE techniques, such as best-worst scaling, would be beneficial to identify how preference-elicitation tasks can be developed and applied with people with intellectual disabilities to ensure that future service innovations are designed and administered in ways which best meet their needs and preferences.
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Brown MS, Hallford DM, Galyean ML, Krehbiel CR, Duff G. Effect of ruminal glucose infusion on dry matter intake, urinary nitrogen composition, and serum metabolite and hormone profiles in Ewes. J Anim Sci 1999; 77:3068-76. [PMID: 10568479 DOI: 10.2527/1999.77113068x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Twelve 18-mo-old Debouillet ewes were used to determine the effect of ruminal glucose infusion on DMI, on urinary ammonium (NH4+) and urea N (UUN) concentrations, and on serum metabolite and hormone profiles. Ewes were limit-fed a 90% concentrate diet for 30 d, stratified by BW into three groups (average BW = 82.6+/-1.1 kg), and assigned randomly to receive 0, 5, or 10 g of glucose/kg of BW via esophageal intubation. Urine was collected hourly for 12 h and blood (jugular venipuncture) at 30-min intervals for 12 h. After 12 h, ewes were housed individually, allowed free access to the diet, and DMI was recorded for 5 d. Venous blood pH averaged 7.49, 7.48, and 7.48 at 0 h and decreased (linear [L], P < .01) at 12 h (7.41, 7.36, and 7.26) with increasing glucose. Serum glucose increased (L, P = .06) at 3 and 6 h. Serum L(+)-lactate increased (L, P = .08) at 3, 6, and 9 h, whereas serum D(-)-lactate increased linearly (P = .09) at 6 and 9 h and quadratically (P < .10) at 12 h. After the glucose challenge, DMI decreased (L, P < .05). Urinary pH and NH4+ were not influenced by glucose infusion; however, UUN increased at 3 (quadratic [Q], P < .05), 4, 5, 6 (L, P = .03), and 7 h (Q, P < .05) and decreased at 11 and 12 h (L, P = .09). As glucose infusion increased, serum creatinine increased at 9 (L, P < .01) and 12 h (Q, P = .02). Generally, serum Na and P increased (P = .09), whereas K decreased (P < .05), with glucose infusion. Lactate dehydrogenase activity increased with glucose infusion (Q, P < .10) at 3, 6, 9, and 12 h. Increasing glucose infusion increased serum globulin (Q, P = .06), albumin, and total protein (L, P = .08). Serum prolactin and vasopressin were not influenced (P = .22) by glucose infusion. Serum insulin and aldosterone increased quadratically (P = .08), whereas serum growth hormone decreased linearly (P = .08) as a result of increasing glucose infusion. Results suggest that UUN, serum insulin, aldosterone, and several serum constituents may serve as markers of organic acid load in ruminants fed high-concentrate diets.
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Coyle P, Duff G, Gavin O, Clarke Moloney M, Burke PE, Kavanagh EG, Grace PA. Can augmentation index be used as an accurate tool in the diagnosis of peripheral obstructive arterial disease? Ir J Med Sci 2012; 181:309-13. [PMID: 22422079 DOI: 10.1007/s11845-011-0796-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2010] [Accepted: 12/24/2011] [Indexed: 01/19/2023]
Abstract
BACKGROUND The use of radial augmentation index (rAI) as an indicator of vascular disease was investigated in the vascular imaging laboratory in a regional hospital. AIMS The aim of this study was to investigate whether a correlation exists between ankle-brachial pressure index (ABPI) and rAI in normal subjects, patients with peripheral obstructive arterial disease, and diabetic patients. METHODS A group of 46 patients and 14 controls had ABPI and rAI measured and factors affecting AI were assessed. RESULTS rAI was found to have a negative correlation with ABPI (Spearman's ρ = -0.513, p < 0.01). There was significant increase in the rAI scores of diabetic patients compared to normal patients (normal median was 64% lower than diabetic median, p < 0.01) and in peripheral obstructive vascular disease patients compared to normal (normal median 69% lower, p < 0.001). Of the various affecting factors, age stood out with rAI having a positive correlation to age (Spearman's ρ = 0.68, p < 0.01). CONCLUSIONS The augmentation index appears be a significant indicator of cardiovascular disease and may be a useful tool in the diagnosis of vascular pathology.
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Crocker M, Milte R, Duff G, Lawless M, Corlis M, Ratcliffe J. Are Australians willing to pay more tax to support wage increases for aged care workers? Findings from a national survey. Australas J Ageing 2022; 41:513-521. [PMID: 35581941 DOI: 10.1111/ajag.13094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 03/21/2022] [Accepted: 04/20/2022] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To explore the perceptions of the Australian public regarding Australia's aged care workforce, including their willingness to pay more tax to fund better pay and conditions for aged care workers. METHODS An online survey was developed and administered to a representative sample of Australian adults (aged ≥18 years) by age group, gender and Australian state. Survey respondents completed a series of attitudinal statements to elicit their perceptions of the value of Australia's aged care workforce and were asked to indicate their willingness to pay additional tax to fund better pay and conditions for aged care workers. Those who gave a positive response were then asked to indicate what percentage of additional tax per year they would be willing to pay to ensure better pay and conditions for aged care workers. RESULTS A total of 2033 adult respondents completed the survey. A majority (78%) of respondents either 'agreed' or 'strongly agreed' that aged care workers should be paid more. Approximately half of the respondents (50.57%) expressed a willingness to pay more tax to ensure better pay and conditions for aged care workers. The mean willingness to pay was 1.31% additional tax overall, and mean percentage additional tax values were relatively consistent across key socio-demographic indicators. CONCLUSIONS A majority of the Australian public are in favour of improving the wages and employment conditions of aged care workers. However, only one in two Australians is willing to pay more tax to ensure better pay and conditions for aged care workers.
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Carey G, Malbon ER, Weier M, Dickinson H, Duff G. Making markets work for disability services: The question of price setting. HEALTH & SOCIAL CARE IN THE COMMUNITY 2019; 27:e716-e723. [PMID: 31215103 DOI: 10.1111/hsc.12780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/06/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Personalisation schemes and associated markets for social care have been a growing trend in industrialised countries over recent decades. While there is no single approach to marketisation of social care and personalisation, often funds are devolved to clients of care services to be used to purchase services directly from market. Such arrangements are vulnerable to market failures and 'thin' markets, causing the need for stewardship of the social care markets. We present findings from a 2018 survey of 626 care service providers in the Australian National Disability Insurance Scheme market on their experience of market conditions. Over 46% of respondents listed 'addressing pricing' as their top action for addressing market problems. Qualitative findings show that central price setting is detached from service delivery realities, affecting service quality and capability building potential. We argue that devolution of price setting to, or at least flexibility and discretion at, the local level is likely to be a key to solving pricing dilemmas in personalisation schemes.
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Nuki G, Duff G. Acknowledgements. Rheumatology (Oxford) 1985. [DOI: 10.1093/rheumatology/xxiv.suppl_1.ix] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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