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Mistry K, Gerrard N, Hodgson A. Wetting of a Stepped Platinum (211) Surface. J Phys Chem C Nanomater Interfaces 2023; 127:4741-4748. [PMID: 36925560 PMCID: PMC10009809 DOI: 10.1021/acs.jpcc.2c08360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/12/2023] [Indexed: 06/18/2023]
Abstract
Steps stabilize water adsorption on metal surfaces, providing favorable binding sites for water during wetting or ice nucleation, but there is limited understanding of the local water arrangements formed on such surfaces. Here we describe the structural evolution of water on the stepped Pt(211) surface using thermal desorption, low-energy electron diffraction, and scanning tunneling microscopy to probe the water structure. At low coverage water forms linear structures comprising zigzag chains along the steps that are decorated by H-bonded rings every one or two units along the terrace. Simple 2-coordinate H-bonded chains are not observed, indicating the Pt step binds too weakly to compensate entirely for a low water H-bond coordination number. As the coverage increases, water chains assemble into a disordered (2 × 1) structure, likely made up of the same narrow water chains along the steps with little or no H-bonding between adjacent structures. The chain structure disappears as water adsorption saturates the surface to form an incommensurate, disordered network of water rings of different size. Although the steps on Pt(211) clearly stabilize water adsorption and direct growth, the surface does not support the simple 1D chains previously proposed or an ordered 2D network such as seen on other surfaces. We discuss reasons for this and the factors that determine the behavior of the first water layer on stepped metal surfaces.
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Greenwell CN, Born KS, Admiraal R, Hodgson A, Dunlop JN, Loneragan NR. Social facilitation for conservation planning: understanding fairy tern behavior and site selection in response to conspecific audio-visual cues. ENDANGER SPECIES RES 2021. [DOI: 10.3354/esr01127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Simulated social facilitation techniques (e.g. decoys and call playbacks) are commonly used to attract seabirds to restored and artificially created nesting habitats. However, a lack of social stimuli and conspecific cueing at these habitats may limit the use of these sites, at least in the short term. Therefore, testing the effectiveness of simulated audio-visual cues for attracting gregarious birds is important for conservation planning. In this study, we (1) assessed whether call playback and decoys were associated with an increased likelihood of Australian fairy terns Sternula nereis nereis visiting potentially suitable nesting habitats; (2) tested their behavioral response to different cues; and (3) documented whether social facilitation had the potential to encourage colony establishment. A full cross-over study design consisting of all possible pairings of decoy and call playback treatments (control [no attractants], decoys, call playback, both decoys and playback), allocated as part of a random block design, was undertaken at 2 sites. Linear modeling suggested that call playback was important in explaining the time spent aerial prospecting as well as the maximum number of fairy terns aerial prospecting, although this only appeared to be the case for 1 of the 2 sites. Decoys, on the other hand, did not appear to have any effect on time spent aerial prospecting. The results from this study suggest that audio cues have the potential to encourage site selection by increasing social stimuli, but attractants may be required over several breeding seasons before colonies are established.
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Affiliation(s)
- CN Greenwell
- Conservation and Environmental Sciences, College of SHEE, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
| | - KS Born
- Conservation Council of Western Australia, Lotteries West House, 2 Delhi Street, West Perth, Western Australia 6150, Australia
| | - R Admiraal
- Victoria University of Wellington, School of Mathematics and Statistics, Kelburn Parade, Wellington 6012, New Zealand
| | - A Hodgson
- Conservation and Environmental Sciences, College of SHEE, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
| | - JN Dunlop
- Conservation and Environmental Sciences, College of SHEE, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- Conservation Council of Western Australia, Lotteries West House, 2 Delhi Street, West Perth, Western Australia 6150, Australia
| | - NR Loneragan
- Conservation and Environmental Sciences, College of SHEE, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
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Abstract
Bimetallic Pt catalysts are of interest as water redox catalysts in low temperature fuel cells. Here we compare water and hydroxyl adsorption on Pt-Ni(111) films and a PtNi(111) alloy surface with the behaviour on the pure metals. Whereas water adsorbs and desorbs intact from close packed Pt and Ni, it dissociates on PtNi surfaces to form adsorbed hydroxyl and hydrogen. Reactivity to water increases in the order Pt(111) < monolayer Pt-Ni(111) < multilayer (2-6 ML) Pt-Ni(111) ∼ PtNi(111) surface alloy and does not scale directly with the Pt strain. Hydroxyl can also be formed by reaction with pre-adsorbed O and is less stable than on pure Pt, decomposing to water and O in a broad peak near 180 K, 20 K lower than on Pt(111). The reduced stability of OH on Pt-Ni(111) films is common to all the PtNi surfaces and consistent with bimetallic PtNi surfaces showing less blocking by OH during the oxygen reduction reaction.
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Affiliation(s)
- F McBride
- The University of Liverpool, Surface Science Research Centre, Liverpool, UK.
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Puncher M, Pellow PGD, Hodgson A, Etherington G, Birchall A. The Mayak Worker Dosimetry System (MWDS-2013): A Bayesian Analysis to Quantify Pulmonary Binding of Plutonium in Lungs Using Historic Beagle Dog Data. Radiat Prot Dosimetry 2017; 176:32-44. [PMID: 27555656 DOI: 10.1093/rpd/ncw243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 06/06/2023]
Abstract
The revised human respiratory tract model, published in Part 1 of the International Commission on Radiological Protection's (ICRP) report on Occupational Intakes of Radionuclides (OIR), includes a bound fraction, fb, to represent radionuclides that have become chemically bound in the lungs following dissolution of particulates in lung fluid. Bound radionuclides are not subject to particle transport clearance but can be absorbed to blood at a rate, sb. The occurrence of long-term binding of plutonium can greatly increase lung doses, particularly if it occurs in the bronchial and bronchiolar regions. However, there has been little evidence that currently supports the existence of a long-term bound state for plutonium. The present work describes the analysis of measurements of lung data obtained from a life span study of Beagle dogs that were exposed by inhalation to different concentrations of plutonium-239 (239Pu) nitrate aerosol at Pacific Northwest Laboratories, USA. The data have been analysed to assess whether a bound state was required to explain the data. A Bayesian approach was adopted for the analysis that accounts for uncertainties in model parameter values, including uncertainties in the rates of particle transport clearance. Furthermore, it performs the analysis using two different modelling hypotheses: a model based on the current ICRP human respiratory tract model and its treatment of alveolar particle transport clearance; and a model of particle transport clearance that is based on the updated model developed by ICRP to calculate dose coefficients for the OIR. The current model better represents clearance in dogs at early times (up to 1 year following intake) and the latter better represents retention at greater times (>5 years following intake). The results indicate that a long-term bound fraction of between 0.16 and 1.1%, with a mean value of between 0.24 and 0.8% (depending on the model) is required to explain the data.
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Affiliation(s)
- M Puncher
- Department of Toxicology, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, DidcotOX11 0RQ, United Kingdom
| | - P G D Pellow
- Department of Radiation Hazards and Emergencies, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, DidcotOX11 0RQ, United Kingdom
| | - A Hodgson
- Department of Toxicology, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, DidcotOX11 0RQ, United Kingdom
| | - G Etherington
- Department of Radiation Hazards and Emergencies, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, DidcotOX11 0RQ, United Kingdom
| | - A Birchall
- Global Dosimetry, 1 Macdonald Close, Didcot, OxonOX11 7BH, United Kingdom(formerly PHE1)
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Affiliation(s)
- F. McBride
- Department of Chemistry, Surface Science Research Centre, University of Liverpool, Liverpool L69 3BX, UK
| | - A. Hodgson
- Department of Chemistry, Surface Science Research Centre, University of Liverpool, Liverpool L69 3BX, UK
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Darling GR, Forster M, Lin C, Liu N, Raval R, Hodgson A. Chiral segregation driven by a dynamical response of the adsorption footprint to the local adsorption environment: bitartrate on Cu(110). Phys Chem Chem Phys 2017; 19:7617-7623. [DOI: 10.1039/c7cp00622e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Bitartrate, a strongly bound chiral modifier, is able to restructure its adsorption footprint on Cu(110) in response to local adsorbates.
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Affiliation(s)
- G. R. Darling
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
| | - M. Forster
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
| | - C. Lin
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
| | - N. Liu
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
| | - R. Raval
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
| | - A. Hodgson
- Surface Science Research Centre and Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX
- UK
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Baiden F, Malm K, Bart-Plange C, Hodgson A, Chandramohan D, Webster J, Owusu-Agyei S. Shifting from presumptive to test-based management of malaria - technical basis and implications for malaria control in Ghana. Ghana Med J 2015; 48:112-22. [PMID: 25667560 DOI: 10.4314/gmj.v48i2.10] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The presumptive approach was the World Health Organisation (WHO) recommended to the management of malaria for many years and this was incorporated into syndromic guidelines such as the Integrated Management of Childhood Illnesses (IMCI). In early 2010 however, WHO issued revised treatment guidelines that call for a shift from the presumptive to the test-based approach. Practically, this implies that in all suspected cases, the diagnosis of uncomplicated malaria should be confirmed using rapid test before treatment is initiated. This revision effectively brings to an end an era of clinical practice that span several years. Its implementation has important implications for the health systems in malaria-endemic countries. On the basis of research in Ghana and other countries, and evidence from program work, the Ghana National Malaria Control Program has issued revised national treatment guidelines that call for implementation of test-based management of malaria in all cases, and across all age groups. This article reviews the evidence and the technical basis for the shift to test-based management and examines the implications for malaria control in Ghana.
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Affiliation(s)
- F Baiden
- Kintampo Health Research Centre, Ghana Health Service, Ghana
| | - K Malm
- National Malaria Control Program, Ghana Health Service, Ghana
| | - C Bart-Plange
- National Malaria Control Program, Ghana Health Service, Ghana
| | - A Hodgson
- Health Research and Development Division, Ghana Health Service, Ghana
| | - D Chandramohan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, U.K
| | - J Webster
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, U.K
| | - S Owusu-Agyei
- Kintampo Health Research Centre, Ghana Health Service, Ghana
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August J, Brouard M, Docker MP, Hodgson A, Milne CJ, Simons JP. Vector Correlations in Molecular Photodissociation: H2O2, HONO2and (CH3)3COOH. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/bbpc.198800061] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Catterson P, Moore B, Hodgson A, Lewis N, Newell J, Charles P. A CASE STUDY OF TWO PREMIERSHIP FOOTBALLERS WITH SICKLE CELL TRAIT USING NOVEL TESTS OF REDOX HOMEOSTASIS. Br J Sports Med 2014. [DOI: 10.1136/bjsports-2014-093494.47] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Massey A, McBride F, Darling GR, Nakamura M, Hodgson A. The role of lattice parameter in water adsorption and wetting of a solid surface. Phys Chem Chem Phys 2014; 16:24018-25. [DOI: 10.1039/c4cp03164d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Reducing the lattice parameter of a Sn–metal surface alloy below the O–O separation of ice disrupts the flat wetting layer, causing the first layer to buckle and instead form ice clusters.
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Affiliation(s)
- A. Massey
- Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX, UK
| | - F. McBride
- Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX, UK
| | - G. R. Darling
- Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX, UK
| | - M. Nakamura
- Graduate School of Engineering
- Chiba University
- Chiba 2638522, Japan
| | - A. Hodgson
- Department of Chemistry
- University of Liverpool
- Liverpool L69 3BX, UK
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Oduro A, Anyorigiya T, Anto F, Amenga-Etego L, Ansah N, Atobrah P, Ansah P, Koram K, Hodgson A. A randomized, comparative study of supervised and unsupervised artesunate–amodiaquine, for the treatment of uncomplicated malaria in Ghana. Annals of Tropical Medicine & Parasitology 2013; 102:565-76. [DOI: 10.1179/136485908x337508] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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12
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Oduro AR, Anyorigiya T, Adjuik M, Afful TM, Anto F, Atuguba F, Owusu-Agyei S, Hodgson A. A randomized, comparative study of two regimens of β-artemether for the treatment of uncomplicated,Plasmodium falciparummalaria, in northern Ghana. Annals of Tropical Medicine & Parasitology 2013; 98:433-40. [PMID: 15257791 DOI: 10.1179/000349804225003532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In Ghana, wide-spread resistance to chloroquine has necessitated the drug's replacement as the first-line treatment for malaria, both to increase the likelihood of cure and to reduce transmission. To see if beta-artemether could be a suitable alternative to chloroquine, 223 adults (aged > or = 15 years) with uncomplicated, Plasmodium falciparum malaria were each given a total dose of 480 mg beta-artemether over 4 or 5 days. The patients were randomly allocated to receive an initial, loading dose of 80 or 160 mg, and were checked on days 1, 2, 3, 4 (or 5), 7 and 14, for fever clearance and any adverse events. Blood samples collected on days 0, 4 (or 5), 7 and 14 were smeared so that levels of parasitaemia could be evaluated. Haemoglobin concentrations on days 0 and 14 were also determined. In terms of the clinical cure 'rates' estimated in the intention-to-treat analysis (92.5% v. 97.4%) and the evaluability analysis (98.9% v. 100%), and of the frequency of parasitological cure by day 14 (97.0% v. 96.5%), the patients given an initial dose of 80 mg were similar to those given 160 mg as the loading dose. The regimen with the 160-mg loading dose appears as safe and as effective as the regimen with an initial dose of 80 mg. Since the regimen with the higher loading dose is shorter and involves fewer treatments than the other regimen, it would probably be associated with better compliance.
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Affiliation(s)
- A R Oduro
- Navrongo Health Research Centre, P. O. Box 114, Navrongo, Ghana and Navrongo War Memorial Hospital, P. O. Box 34, Navrongo, Ghana.
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Engmann C, Adongo P, Aborigo RA, Gupta M, Logonia G, Affah G, Waiswa P, Hodgson A, Moyer CA. Infant illness spanning the antenatal to early neonatal continuum in rural northern Ghana: local perceptions, beliefs and practices. J Perinatol 2013; 33:476-81. [PMID: 23348868 DOI: 10.1038/jp.2012.151] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To explore community understanding of perinatal illness in northern Ghana. STUDY DESIGN A cross-sectional descriptive study design. RESULT 253 community members participated in in-depth interviews and focus group discussions, including women with newborn infants, grandmothers and health care providers. Four overarching themes emerged: (1) Local understanding of illness affects treatment practices. Respondents recognized danger signs of illness spanning antenatal to early neonatal periods. Understanding of causation often had a distinctly local flavor, and thus treatment sometimes differed from mainstream recommendations; (2) Mothers are frequently blamed for their infant's illness; (3) Healthcare decisions regarding infant care are often influenced by community members aside from the infant's mother and (4) Confidence in healthcare providers is issue-specific, and many households use a blended approach to meet their health needs. CONCLUSION Despite widespread recognition of danger signs and reported intentions to treat ill infants through the formal health care system, traditional approaches to perinatal illness remain common. Interventions need to be aligned with community perceptions if they are to succeed.
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Affiliation(s)
- C Engmann
- Neonatal-Perinatal Medicine, Department of Pediatrics, University of North Carolina Schools of Medicine and Public Health, Chapel Hill, NC 27599-7596, USA.
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Kiani R, Tyrer F, Hodgson A, Berkin N, Bhaumik S. Urban-rural differences in the nature and prevalence of mental ill-health in adults with intellectual disabilities. J Intellect Disabil Res 2013; 57:119-127. [PMID: 22292906 DOI: 10.1111/j.1365-2788.2011.01523.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND In the general population there are statistically significant urban-rural differences in the rate of common mental disorders. In people with intellectual disability (ID) no study has attempted to address this issue. AIMS To compare the prevalence of mental illness, autism spectrum disorder (ASD) and behaviour disorder in people with ID living in urban areas with those living in rural areas. METHODS Cross-sectional study of 2713 individuals registered with an ID service. Participants were assigned to urban or rural groups using the Department for Environment Food and Rural Affairs rural/urban local authority classification for their district. The main outcome variable was a clinical diagnosis of mental illness, ASD and behaviour disorder. Differences between diagnoses of mental illness in urban and rural areas were evaluated using the chi-squared test for the difference in two independent proportions. RESULTS No differences were observed between gender, age and level of ID of service users based on their place of residence. But more people from an ethnic minority background were living in urban areas than rural areas. No differences were observed in the overall prevalence of mental illness by place of residence. However, the results showed that ASD was more common in people living in rural areas. CONCLUSIONS We found these results surprising and at odds with the majority of studies carried out in the general population and propose several reasons for the differences found. We believe that the results and further studies in this area will help inform health service provision for those with ID who live in different geographical areas.
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Affiliation(s)
- R Kiani
- Leicestershire Partnership NHS Trust, Leicester, UK.
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Murphy M, Laycock R, Goharpey N, Bridie J, Faragalla D, Fithall K, Hodge K, Hodgson A, Hoystead C, Koyu Z, Shilton A, Tsoutsoulis K, Ucarli C, Brown A, Crewther D, Crewther S. The Role of Dorsal Stream Development in Form and Motion Coherence and Object Recognition: The Childhood Challenge of Processing Transient Events. J Vis 2012. [DOI: 10.1167/12.9.1368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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16
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McBride F, Omer A, Clay CM, Cummings L, Darling GR, Hodgson A. Strain relief and disorder in commensurate water layers formed on Pd(111). J Phys Condens Matter 2012; 24:124102. [PMID: 22394691 DOI: 10.1088/0953-8984/24/12/124102] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Water adsorbs and desorbs intact on Pd(111), forming a hydrogen-bonded wetting layer whose structure we examine by low energy electron diffraction (LEED) and He atom scattering (HAS). LEED shows that water forms commensurate (√3 × √3)R30° clusters that aggregate into a partially ordered, approximately (7 × 7) superstructure as the layer completes. HAS indicates that the water layer remains disordered on a local (approximately 10 Å) scale. Based on workfunction measurements and density functional theory simulations we propose that water forms small, flat domains of a commensurate (√3 × √3)R30° water network, separated by disordered domain boundaries containing largely H-down water. This arrangement allows the water layer to adapt its density and relieve the lateral strain associated with adsorbing water in the optimum flat atop adsorption site. We discuss different possibilities for the structure of these domain walls and compare this strain relief mechanism to the highly ordered, large unit cell structures formed on surfaces such as Pt(111).
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Affiliation(s)
- F McBride
- Surface Science Research Centre, University of Liverpool, Liverpool L69 3BX, UK
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Flammini D, Pietropaolo A, Senesi R, Andreani C, McBride F, Hodgson A, Adams MA, Lin L, Car R. Spherical momentum distribution of the protons in hexagonal ice from modeling of inelastic neutron scattering data. J Chem Phys 2012; 136:024504. [DOI: 10.1063/1.3675838] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Parr A, Hodgson A, Duddle C, Carby J. Study of patients known to a hospice service: hospital versus home deaths. BMJ Support Palliat Care 2011. [DOI: 10.1136/bmjspcare-2011-000105.198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Waddell J, Hodgson A, Wiseman J. Improving practice through audit: administration of blood transfusions within a hospice setting. BMJ Support Palliat Care 2011. [DOI: 10.1136/bmjspcare-2011-000105.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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20
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Baiden F, Baiden R, Williams J, Akweongo P, Clerk C, Debpuur C, Philips J, Hodgson A. Review of Antenatal-Linked Voluntary Counseling and HIV Testing in Sub-Saharan Africa: Lessons and Options for Ghana. Ghana Med J 2011; 39:8-13. [PMID: 17299534 PMCID: PMC1790809 DOI: 10.4314/gmj.v39i1.35974] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
SummaryVoluntary counselling and HIV testing has become an integral part of HIV prevention and care programs in many countries in sub-Saharan Africa. A number of interventions offer potential to reduce mother-to-child HIV transmission. These interventions, including antenatal and or intrapartum administration of antiretroviral drugs require the integration of voluntary counselling and HIV testing for pregnant women into antenatal care. Ghana's strategic framework for HIV control calls for the integration of voluntary counselling and HIV testing to antenatal care nationwide. It sets as target, the year 2005 when VCT would be widely available and accessible in the country. This paper reviews medline-indexed publications on antenatal-linked VCT programs of sub-Saharan Africa. Four critical themes were used in the medline search. These are acceptability, rates of return for test, disclosure of results vis-à-vis confidentiality and cost effectiveness. The growing consensuses on these issues are discussed in relations to the findings of a recent study conducted among 270 pregnant women in Navrongo in the Kassena-Nankana district of northern Ghana. Suggestions are made to guide the on-going pilot VCT and prevention of mother-to-child programs in Ghana. It is also suggested on the basis of the review and the findings of the Navrongo study that Ghana should explore options likely to promote universal access and overall acceptability. These include couple counselling, guarantee of confidentiality, free testing and continuum of care for mothers who are test positive.
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Affiliation(s)
- F Baiden
- Navrongo Health Research Center, Ghana Health Service, Upper East Region, Ghana
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Oduro A, Ansah P, Hodgson A, Afful T, Baiden F, Adongo P, Koram K. Trends in the prevalence of female genital mutilation and its effect on delivery outcomes in the kassena-nankana district of northern ghana. Ghana Med J 2011; 40:87-92. [PMID: 17299573 PMCID: PMC1790849 DOI: 10.4314/gmj.v40i3.55258] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
UNLABELLED Summary RATIONAL Female genital mutilation (FGM) is prevalent in northern Ghana, as the practice is seen as a passage rite to women adulthood and thus undertaken just before marriage. OBJECTIVES We determined the changes in trend of FGM in deliveries at the Navrongo War Memorial hospital, and compared the outcomes and FGM status. DESIGN Retrospective extraction and analysis of delivery data at the hospital from 1(st) January 1996 to 31(st) December 2003. RESULTS Of the 5071 deliveries, about 29% (1466/5071) were associated with FGM. The highest prevalence (95% CI) of 61.5% (50.9, 71.2) was in women aged 40 years and above, and the lowest of 14.4% (11.7, 17.0) was in women below 20 years. The all-age prevalence of FGM showed a significant decline (p-value for linear trend < 0.01) from 35.2% in 1996 to 21.1% in 2003. About 6% (89/1466) of mothers with FGM had stillbirths compared with about 3% (123/3605) of mothers without FGM. Again FGM was associated with 8.2% (120/1466) caesarean section rate compared with 6.7% (241/3605) in mothers without FGM. Mean birth weight and frequency of low birth weights were not significantly associated with FGM status. CONCLUSION Although there is a high rate of FGM among mothers in the district and is associated with a higher proportion of stillbirths and caesarean sections, practice has shown a significant decline in the district in recent years due to the prevailing campaigns and intervention studies. There is therefore the need to sustain the ongoing intervention efforts.
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Affiliation(s)
- Ar Oduro
- Navrongo Health Research Centre, P.O. Box 114, Navrongo, Ghana
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Sereewatthanawut I, Baptista I, Boam A, Hodgson A, Livingston A. Nanofiltration process for the nutritional enrichment and refining of rice bran oil. J FOOD ENG 2011. [DOI: 10.1016/j.jfoodeng.2010.07.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Hodgson A, Simons JP, Ashfold MNR, Bayley JM, Dixon RN. Rotational State Dependence of the Predissociation Dynamics in H2O, D2O (C̃1B1 and β1A1). ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19850890311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Stradling GN, Gray SA, Ellender M, Moody JC, Hodgson A, Pearce M, Wilson I, Burgada R, Bailly T, Leroux YG. The Efficacies of 3,4,3-LIHOPO and DTPA for Enhancing the Excretion of Plutonium and Americium from the Rat: Comparison with Other Siderophore Analogues. Int J Radiat Biol 2009; 62:487-97. [PMID: 1357063 DOI: 10.1080/09553009214552381] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
With DTPA as a comparison, the siderophore analogue code named 3,4,3-LIHOPO has been tested for its ability to remove 238Pu and 241Am from rats after their inhalation or intravenous injection as nitrate. The most effective treatment regimen for inhaled Pu was the repeated administration of 30 mumol kg-1 3,4,3-LIHOPO. By 7 days after exposure, the Pu contents of the lungs and total body were reduced respectively to 2 and 4% of those in untreated animals. These values were six and three times less than when DTPA was administered using the same protocol. For inhaled Am, 3,4,3-LIHOPO and DTPA were considered equally effective, the lung and total body contents being reduced respectively to 13 and 10% of those in controls. Some animals showed slight degenerative changes in the liver and proximal tubules of the kidneys after the repeated administration of 30 mumol kg-1 of 3,4,3-LIHOPO; however these changes were less marked than after DTPA treatment. After the intravenous injection of Pu, the most effective regimen was the single administration of 3 mumol kg-1 3,4,3-LIHOPO. The body content at 7 days was reduced to 7% controls compared with 19% after the repeated administration of 30 mumol kg-1 DTPA. At a dosage of 30 mumol kg-1, 3,4,3-LIHOPO was less effective owing to the higher retention of Pu in the liver. With repeated dosages of 30 mumol kg-1 3,4,3-LIHOPO was more effective than DTPA for the decorporation of Am; the body contents were 16 and 31% of those in controls respectively. Importantly, the body content was still reduced to 28% of control after a single administration of 3 mumol kg-1. The ligand 3,4,3-LIHOPO, which is also superior to other siderophore analogues, could represent a most significant development in the decorporation of Pu and Am.
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Affiliation(s)
- G N Stradling
- National Radiological Protection Board, Didcot, Oxon, UK
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Rateau-Matton S, Ansoborlo E, Hodgson A. Comparative absorption parameters of Pu and Am from PuO2and mixed oxide aerosols measured afterin vitrodissolution test and inhalation in rats. Int J Radiat Biol 2009; 80:777-85. [PMID: 15799623 DOI: 10.1080/09553000400017978] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare specific absorption parameter values obtained from in vitro dissolution studies (this paper) and in vivo experiments (data published by Ramounet et al, 2000) and to determine their influence on Dose Per Unit Intake (DPUI) calculations. MATERIALS AND METHODS Experiments were performed on plutonium oxide (PuO2) and two Mixed Oxide (MOx) preparations containing 5% Pu (w/w) made according to the industrial process in vitro using a static test and in vivo after rat inhalation. RESULTS Behaviour of Pu and Am shows, in vitro, at shorter times, a greater rapid dissolution fraction f(r) for Pu (factor 10) and Am (factor 2) with MOx powders compared with PuO2, whereas in vivo results show a greater fraction f(r) for Pu (factor 5) and Am (factor 15) with PuO2 compared with MOx powders. This phenomenon has not been observed for slow dissolution absorption parameter s(s). The in vivo parameters for Pu and Am in these materials were very close to the default values recommended by International Commission for Radiological Protection for default Type S. CONCLUSIONS Results obtained have shown that solubility of Pu from the mixed oxide was higher than that of Pu from PuO2. Nevertheless, no significant difference was observed between the three compounds in the corresponding dose coefficients in vivo or in vitro. Therefore, for these particular compounds, variation in the chemical composition of the aerosols had no significant influence on DPUI. Consequently, in vitro, the dissolution test can provide a good estimate of the in vivo behaviour. Studies of variation of % Pu (w/w) from MOx are in progress in our laboratory to confirm these conclusions.
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Affiliation(s)
- S Rateau-Matton
- Laboratoire de Radiotoxicologie, CEA/DSV/DRR/SRCA/LRT, BP n 12, 91680 Bruyères-Le-Châtel, France.
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Akazili J, Adjuik M, Chatio S, Kanyomse E, Hodgson A, Aikins M, Gyapong J. What are the Technical and Allocative Efficiencies of Public Health Centres in Ghana? Ghana Med J 2008; 42:149-55. [PMID: 19452023 PMCID: PMC2673839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
INTRODUCTION Health systems in developing countries including Ghana are faced with critical resource constraints in pursuing the goal of improving the health status of the population. The constrained ability to adequately meet health care needs is exacerbated by inefficiency in the health care systems, especially within public health centres. METHODS The study used Data Envelopment Analysis (DEA) method, to calculate the technical and allocative efficiency of 113 randomly sampled health centres. A logistic regression model was also applied on whether a health centre was technically efficient or not to determine the factors that significantly influence the efficiency of health centres. FINDINGS The findings showed that 78% of health centres were technically inefficient and so were using resources that they did not actually need. Eight-eight percent were also allocatively inefficient. The overall efficiency, (product of the technical and allocative efficiency), was also calculated and over 90% of the health centres were inefficient. The results of a logistic regression analysis show that newer health centres and those which receive incentives were more likely to be technically efficient compared to older health centres and those who did receive incentives. CONCLUSION The results broadly point to grave inefficiency in the health care delivery system of the health centres and that lots of resources could be saved if measures were put in place to curb the waste. Incentives to health centres were found to be major motivating factors to the promotion of efficiency.
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Affiliation(s)
- J Akazili
- Navrongo Health Research Centre, Health Research Unit, Ghana Health Service, P.O. Box 114, Navrongo, UE/R, Ghana
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Lopez MA, Etherington G, Castellani CM, Franck D, Hurtgen C, Marsh JW, Nosske D, Breustedt B, Blanchardon E, Andrasi A, Bailey MR, Balashazy I, Battisti P, Bérard P, Birchall A, Broggio D, Challeton-de-Vathaire C, Cruz-Suarez R, Doerfel H, Giussani A, Hodgson A, Koukouliou V, Kramer GH, Le Guen B, Luciani A, Malatova I, Molokanov A, Moraleda M, Muikku M, Oeh U, Puncher M, Rahola T, Stradling N, Vrba T. Internal dosimetry: towards harmonisation and coordination of research. Radiat Prot Dosimetry 2008; 131:28-33. [PMID: 18757895 DOI: 10.1093/rpd/ncn217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The CONRAD Project is a Coordinated Network for Radiation Dosimetry funded by the European Commission 6th Framework Programme. The activities developed within CONRAD Work Package 5 ('Coordination of Research on Internal Dosimetry') have contributed to improve the harmonisation and reliability in the assessment of internal doses. The tasks carried out included a study of uncertainties and the refinement of the IDEAS Guidelines associated with the evaluation of doses after intakes of radionuclides. The implementation and quality assurance of new biokinetic models for dose assessment and the first attempt to develop a generic dosimetric model for DTPA therapy are important WP5 achievements. Applications of voxel phantoms and Monte Carlo simulations for the assessment of intakes from in vivo measurements were also considered. A Nuclear Emergency Monitoring Network (EUREMON) has been established for the interpretation of monitoring data after accidental or deliberate releases of radionuclides. Finally, WP5 group has worked on the update of the existing IDEAS bibliographic, internal contamination and case evaluation databases. A summary of CONRAD WP5 objectives and results is presented here.
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Affiliation(s)
- M A Lopez
- CIEMAT, Centro de Investigaciones Energéticas Medioambientales y Tecnologicas, Avda Complutense 22, 28040 Madrid, Spain.
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Abstract
With the experimental evolution of fusion power the levels of tritium used will increase as will the potential for human exposure. Tritium-loaded carbon particles produced during the experimental operation of the Joint European Torus fusion tokamak have been characterised in terms of size, elemental composition and specific activity of tritium elsewhere. The aim of this study was to characterise the dissolution of tritium from these particles in order to derive dose coefficients for this material and provide guidance on monitoring procedures should it be inhaled accidentally. The dissolution of tritium was measured for 100 d in lung serum simulant from two batches of materials, SG1 and SG2, which were obtained from carbon tiles originating from different positions in the reactor. Retention over this period followed a three-component exponential. About 1-5% dissolved within a minute, and up to a further 20% dissolved over 100 d for the SG1 materials but <1% for the SG2 materials. Dissolution between the SG1 materials varied greatly, whereas the SG2 materials were similar. As a result of this variability, the assessed dose from urinary excretion could be in error by up to two orders of magnitude depending on the material inhaled. It is recommended that (i) the dissolution is measured for a wider range of materials, preferably dusts collected in working areas, and (ii) in vivo studies are performed to characterise fully the urine excretion of tritium from these materials. This information could be used to provide improved guidance on dose assessment after special or routine monitoring, taking account of the likely variation of particle size and biological retention half times.
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Affiliation(s)
- S A Hodgson
- Health Protection Agency, Radiation Protection Division, Chilton, Didcot, Oxon OX11 0RQ, UK.
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Hodgson A, Helmy N, Masri BA, Greidanus NV, Inkpen KB, Duncan CP, Garbuz DS, Anglin C. Comparative repeatability of guide-pin axis positioning in computer-assisted and manual femoral head resurfacing arthroplasty. Proc Inst Mech Eng H 2007; 221:713-24. [PMID: 18019459 DOI: 10.1243/09544119jeim284] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The orientation of the femoral component in hip resurfacing arthroplasty affects the likelihood of loosening and fracture. Computer-assisted surgery has been shown to improve significantly the surgeon's ability to achieve a desired position and orientation; nevertheless, both bias and variability in positioning remain and can potentially be improved. The authors recently developed a computer-assisted surgical (CAS) technique to guide the placement of the pin used in femoral head resurfacing arthroplasty and showed that it produced significantly less variation than a typical manual technique in varus/valgus placement relative to a pre-operatively determined surgical plan while taking a comparable amount of time. In the present study, the repeatability of both the CAS and manual techniques is evaluated in order to estimate the relative contributions to overall variability of surgical technique (CAS versus manual), surgeon experience (novice versus experienced), and other sources of variability (e.g. across specimens and across surgeons). This will enable further improvements in the accuracy of CAS techniques. Three residents/fellows new to femoral head resurfacing and three experienced hip arthroplasty surgeons performed 20-30 repetitions of each of the CAS and manual techniques on at least one of four cadaveric femur specimens. The CAS system had markedly better repeatability (1.2°) in varus/valgus placement relative to the manual technique (2.8°), slightly worse repeatability in version (4.4° versus 3.2°), markedly better repeatability in mid-neck placement (0.7 mm versus 2.5 mm), no significant dependence on surgeon skill level (in contrast to the manual technique), and took significantly less time (50 s versus 123 s). Proposed improvements to the version measurement process showed potential for reducing the standard deviation by almost two thirds. This study supports the use of CAS for femoral head resurfacing as it is quicker than the manual technique, independent of surgeon experience, and demonstrates improved repeatability.
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Affiliation(s)
- A Hodgson
- Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada
- Institute for Computing, Information and Cognitive Systems, University of British Columbia, Vancouver, Canada
| | - N Helmy
- Department of Orthopaedics, University of British Columbia, Vancouver, Canada
| | - B A Masri
- Department of Orthopaedics, University of British Columbia, Vancouver, Canada
| | - N V Greidanus
- Department of Orthopaedics, University of British Columbia, Vancouver, Canada
| | - K B Inkpen
- Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada
| | - C P Duncan
- Department of Orthopaedics, University of British Columbia, Vancouver, Canada
| | - D S Garbuz
- Department of Orthopaedics, University of British Columbia, Vancouver, Canada
| | - C Anglin
- Department of Mechanical Engineering, University of British Columbia, Vancouver, Canada
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Baiden F, Akanlu G, Hodgson A, Akweongo P, Debpuur C, Binka F. Using lay counsellors to promote community-based voluntary counselling and HIV testing in rural northern Ghana: a baseline survey on community acceptance and stigma. J Biosoc Sci 2007; 39:721-33. [PMID: 17207292 DOI: 10.1017/s0021932006001829] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Access to voluntary counselling and HIV testing (VCT) remains limited in most parts of Ghana with rural populations being the least served. Services remain facility-based and employ the use of an ever-dwindling number of health workers as counsellors. This study assessed approval for the use of lay counsellors to promote community-based voluntary counselling and testing for HIV and the extent of HIV/AIDS-related stigma in the Kassena-Nankana district of rural northern Ghana. A cross-sectional questionnaire survey was conducted. Logistic regression was used to identify predictors of the tendency to stigmatize people living with HIV/AIDS (PLWHAs). Focus group discussions were held and analytical coding of the data performed. The majority (91.1%) of the 403 respondents indicated a desire to know their HIV status. Most (88.1%) respondents considered locations outside of the health facility as preferred places for VCT. The majority (98.7%) of respondents approved the use of lay counsellors. About a quarter (24%) of respondents believed that it was possible to acquire HIV through sharing a drinking cup with a PLWHA. About half (52.1%) of the respondents considered that a teacher with HIV/AIDS should not be allowed to teach, while 77.2% would not buy vegetables from a PLWHA. Respondents who believed that sharing a drinking cup with a PLWHA could transmit HIV infection (OR 2.50, 95%CI 1.52-4.11) and respondents without formal education (OR 2.94, 95%CI 1.38-6.27) were more likely to stigmatize PLWHAs. In contrast, respondents with knowledge of the availability of antiretroviral (ARV) drugs were less likely to do so (OR 0.40, 95%CI 0.22-0.73). Findings from the thirteen focus group discussions reinforced approval for community-based VCT and lay counsellors but revealed concerns about stigma and confidentiality. In conclusion, community-based VCT and the use of lay counsellors may be acceptable options for promoting access. Interventional studies are required to assess feasibility and cost-effectiveness.
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Affiliation(s)
- F Baiden
- Navrongo Health Research Center, Ghana Health Service, Navrongo, UER, Ghana
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Lopez MA, Etherington G, Castellani CM, Franck D, Hurtgen C, Marsh JW, Nosske D, Doerfel H, Andrasi A, Bailey M, Balashazy I, Battisti P, Bérard P, Berkowski V, Birchall A, Blanchardon E, Bonchuk Y, de Carlan L, Cantone MC, Challeton-de Vathaire C, Cruz-Suarez R, Davis K, Dorrian D, Giussani A, Le Guen B, Hodgson A, Jourdain JR, Koukouliou V, Luciani A, Malatova I, Molokanov A, Moraleda M, Muikku M, Oeh U, Puncher M, Rahola T, Ratia H, Stradling N. Coordination of research on internal dosimetry in Europe: the CONRAD project. Radiat Prot Dosimetry 2007; 127:311-6. [PMID: 17686965 DOI: 10.1093/rpd/ncm350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The EUropean RAdiation DOSimetry Group (EURADOS) initiated in 2005 the CONRAD Project, a Coordinated Network for Radiation Dosimetry funded by the European Commission (EC), within the 6th Framework Programme (FP). The main purpose of CONRAD is to generate a European Network in the field of Radiation Dosimetry and to promote both research activities and dissemination of knowledge. The objective of CONRAD Work Package 5 (WP5) is the coordination of research on assessment and evaluation of internal exposures. Nineteen institutes from 14 countries participate in this action. Some of the activities to be developed are continuations of former European projects supported by the EC in the 5th FP (OMINEX and IDEAS). Other tasks are linked with ICRP activities, and there are new actions never considered before. A collaboration is established with CONRAD Work Package 4, dealing with Computational Dosimetry, to organise an intercomparison on Monte Carlo modelling for in vivo measurements of (241)Am deposited in a knee phantom. Preliminary results associated with CONRAD WP5 tasks are presented here.
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Affiliation(s)
- M A Lopez
- CIEMAT, Avda Complutense 22, 28040 Madrid, Spain.
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Ménétrier F, Bérard P, Joussineau S, Stradling N, Hodgson A, List V, Morcillo MA, Paile W, Holt DCB, Eriksson T. TIARA: treatment initiatives after radiological accidents. Radiat Prot Dosimetry 2007; 127:444-8. [PMID: 17545661 DOI: 10.1093/rpd/ncm298] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
This paper describes the objectives, and reviews the progress, of the European project 'Treatment Initiatives After Radiological Accidents' (TIARA). TIARA forms part of the 'Preparatory Action for Security Research' (PASR) launched by the European Commission in 2004. The Preparatory Action is intended to reach preliminary conclusions on the needs for the security of EU citizens. It prepared a comprehensive Security Research Programme as part of the Commission's Seventh Framework Programme proposal, which was adopted in 2006 and launched in 2007. The principal purpose of TIARA is to constitute a European network that will participate in facilitating the management of a crisis in the event of the malevolent dispersal of radionuclides into the public environment.
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Affiliation(s)
- F Ménétrier
- CEA/DSV/CARMIN, Route du Panorama, BP 6, 92265 Fontenay-aux-Roses, France.
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Aduro AR, Owusu-Agyei S, Anyorigiya T, Adjuik M, Hodgson A. Efficacy and acceptability of oral artemether (Artemos<sup>TM</sup>) for the treatment of acute uncomplicated malaria in Ghana. Ghana Med J 2006. [DOI: 10.4314/gmj.v38i2.36000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Schiros T, Haq S, Ogasawara H, Takahashi O, Öström H, Andersson K, Pettersson L, Hodgson A, Nilsson A. Structure of water adsorbed on the open Cu(110) surface: H-up, H-down, or both? Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.08.048] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Karlberg GS, Wahnström G, Clay C, Zimbitas G, Hodgson A. Water desorption from an oxygen covered Pt(111) surface: Multichannel desorption. J Chem Phys 2006; 124:204712. [PMID: 16774369 DOI: 10.1063/1.2200347] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Mixed OH/H2O structures, formed by the reaction of O and water on Pt(111), decompose near 200 K as water desorbs. With an apparent activation barrier that varies between 0.42 and 0.86 eV depending on the composition, coverage, and heating rate of the film, water desorption does not follow a simple kinetic form. The adsorbate is stabilized by the formation of a complete hydrogen bonding network between equivalent amounts of OH and H2O, island edges, and defects in the structure enhancing the decomposition rate. Monte Carlo simulations of water desorption were made using a model potential fitted to first-principles calculations. We find that desorption occurs via several distinct pathways, including direct or proton-transfer mediated desorption and OH recombination. Hence, no single rate determining step has been found. Desorption occurs preferentially from low coordination defect or edge sites, leading to complex kinetics which are sensitive to both the temperature, composition, and history of the sample.
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Affiliation(s)
- G S Karlberg
- Department of Applied Physics, Chalmers University of Technology, S-41296 Göteborg, Sweden.
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Baiden F, Hodgson A, Adjuik M, Adongo P, Ayaga B, Binka F. Trend and causes of neonatal mortality in the Kassena-Nankana district of northern Ghana, 1995-2002. Trop Med Int Health 2006; 11:532-9. [PMID: 16553937 DOI: 10.1111/j.1365-3156.2006.01582.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To describe the trend and causes of neonatal deaths in a rural district in northern Ghana. METHODS Descriptive analysis of data collected from the Navrongo Demographic Surveillance System and verbal autopsies conducted on all neonatal deaths from 1995-2002. RESULTS Of 1118 recorded neonatal deaths 1068 (95.5%) could be analysed. Only 13.2% of deaths occurred at the health facility; 62.7% occurred in the early neonatal period, with prematurity (38%) and birth injuries (19%) as leading causes. Infectious causes (66%) were the major contributors to late neonatal deaths. Infanticide accounted for 4.9% of all neonatal deaths. The cause-specific mortality rate for neonatal tetanus remained under 2.5% throughout the 8-year period. Overall, the neonatal mortality rate declined at an average of 2.5 per 1000 live births per year: Down by nearly 50% from 40.9 (95%C.I. 34.1-46.8) in 1995 to 20.5 (95%C.I.17.3-22.7) in 2002. CONCLUSION The various health interventions undertaken in this district have had the collateral effect of causing decline in neonatal mortality. Neonatal mortality could be further reduced by preventing and treating neonatal infections, having skilled attendance at delivery and the elimination of infanticide. Data from demographic surveillance sites may be useful in monitoring trends in child mortality.
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Affiliation(s)
- F Baiden
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, UER, Ghana.
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Baiden F, Amponsa-Achiano K, Oduro AR, Mensah TA, Baiden R, Hodgson A. Unmet need for essential obstetric services in a rural district in northern Ghana: Complications of unsafe abortions remain a major cause of mortality. Public Health 2006; 120:421-6. [PMID: 16549080 DOI: 10.1016/j.puhe.2005.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2005] [Revised: 11/08/2005] [Accepted: 12/07/2005] [Indexed: 10/24/2022]
Abstract
AIM The aim of this study was to review 4 years of hospital data on antenatal services, deliveries and maternal deaths as the baseline evaluation for a programme to improve care. METHODS Descriptive analyses were made of data extracted from the monthly returns charts and clinical notes on all maternal deaths from January 2001 to December 2003 at the district hospital in the Kassena-Nankana district of rural northern Ghana. RESULTS The majority (56.6%) of women first attended an antenatal clinic during the second trimester, and about 70% had haemoglobin levels of <10 g/dl. A total of 3160 deliveries were recorded. The prevalence of female genital cutting was 21.4%. Hospital and population rates of Caesarean section were 9.1 and 1.8%, respectively. Only one-third of women in need of a Caesarean section were able to access this intervention. Twenty-four maternal deaths were recorded, giving a hospital maternal mortality ratio of 759 per 100,000 live births. Complications of unsafe abortion (29.1%) and haemorrhage (20.8%) were the leading causes of death. Seventy-one percent of deaths occurred in women living within 15 km of the district hospital, and 50% occurred within 24 h of arrival. CONCLUSION Late recourse to the health facility and complications of unsafe abortion are major contributory factors to maternal mortality in this district. A high level of unmet need for essential obstetric services, including access to contraceptive services, exists in this district. Decentralizing the availability of essential obstetric services through health centres to community level is necessary to reduce maternal mortality in developing countries.
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Affiliation(s)
- F Baiden
- Navrongo Health Research Centre, Navrongo, UER, Ghana.
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Balding J, Livingstone WJ, Pittock SJ, Mynett-Johnson L, Ahern T, Hodgson A, Smith OP. The IL-6 G-174C polymorphism may be associated with ischaemic stroke in patients without a history of hypertension. Ir J Med Sci 2006; 173:200-3. [PMID: 16323614 DOI: 10.1007/bf02914551] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Recent data suggest that inflammatory reactions are involved in the pathogenesis of cerebral ischaemia. AIM To investigate whether certain inflammatory genetic polymorphisms are associated with the occurrence of ischaemic stroke. METHODS We investigated the prevalence of six polymorphisms in cytokine genes (IL-6, TNF-alpha, TNF-beta, IL-1beta, IL-10, and IL-1Ralpha) in a group of ischaemic stroke patients (n = 105) and in a control population (n = 389). We analysed the prevalence of these polymorphisms in different stroke subtypes and in relation to outcome six months post-stroke. RESULTS There was no significant variation in cytokine gene polymorphism frequencies between control and stroke populations or for different stroke subtypes. Subgroup analysis demonstrated that the prevalence of the IL-6 -174 CC genotype was significantly lower in stroke patients without a history of hypertension compared to controls. CONCLUSION The IL6 -174 CC genotype may be protective against stroke in those patients who have no history of hypertension. Further studies are required to verify these findings.
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Affiliation(s)
- J Balding
- Thrombosis and Haemostasis Laboratory, Institute of Molecular Medicine, Trinity Centre for Health Sciences, St James's Hospital, Dublin, Ireland
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Abstract
When water is adsorbed on Pt(111) above 135 K several different ice structures crystallize, depending on the thickness of the ice layer. At low coverage water forms extended islands of ice with a (square root(37) x square root(37))R25(o) unit cell, which compresses as the monolayer saturates to form a (square root(39) x square root(39))R16(o) structure. The square root(39) low-energy electron diffraction (LEED) pattern becomes more intense as the second layer grows, remaining bright for films up of 10-15 layers and then fading and disappearing for films more than ca. 40 layers thick. The ice multilayer consists of an ordered square root(39) wetting layer, on which ice grows as a crystalline film which progressively loses its registry to the wetting layer. Ice films more than ca. 50 layers thick develop a hexagonal LEED pattern, the entire film and wetting layer reorienting to form an incommensurate bulk ice. These changes are reflected in the vibrational spectra which show changes in line shape and intensity associated with the different ice structures. Thin amorphous solid water films crystallize to form the same phases observed during growth, implying that these structures are thermodynamically stable and not kinetic phases formed during growth. The change from a square root(39) registry to incommensurate bulk ice at ca. 50 layers is associated with a change in crystallization kinetics from nucleation at the Pt(111) interface in thin films to nucleation of incommensurate bulk ice in amorphous solid water films more than 50 layers thick.
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Affiliation(s)
- G Zimbitas
- Surface Science Research Centre, The University of Liverpool, Oxford Street, Liverpool L69 3BX, United Kingdom
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Baiden F, Remes P, Baiden R, Williams J, Hodgson A, Boelaert M, Buve A. Voluntary counseling and HIV testing for pregnant women in the Kassena-Nankana district of northern Ghana: is couple counseling the way forward? AIDS Care 2005; 17:648-57. [PMID: 16036251 DOI: 10.1080/09540120412331319688] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
This study reports the results of a cross-sectional questionnaire survey undertaken in the Kassena-Nankana district of Ghana to assess the perception and attitude of 270 antenatal clinic attendants towards voluntary counseling and HIV testing. It was found that although 92.6% (95% CI 88.8-95.4) of respondents indicated a willingness to get tested, only 51% (95% CI 45.0-57.2) considered HIV testing for pregnant women to be useful. Most (93.6%) indicated they would like their husbands (partners) to know the result of the test and 52.2% indicated that their husbands would be willing to accompany them to antenatal clinic (ANC) at least once during the pregnancy. The perception of the usefulness of HIV testing (OR = 8.5, 95% CI 1.8-40.0), the willingness to disclose test result to the husband (OR = 13.3, 95% CI 4.0-44.5) and perceived willingness of husband to accompany wife to antenatal clinic (OR = 5.2, 95% CI 1.4-19.8) were found to be independent predictors of a woman's willingness to get tested. The willingness to disclose test result to husband (OR 3.2, 95% CI 1.1-10.5) and knowledge of at least one mode of MTCT HIV transmission (OR = 2.1, 95% CI 1.2-3.6) were found to be independent predictors of a woman's perception that getting tested was useful. The results suggest that for pregnant women in this district, the willingness to get tested for HIV does not equate with the perception of the test's usefulness, and that spouses are likely to exert strong influence on the attitude of pregnant women towards VCT. Couple counseling facilitated through couple-friendly ANC services should be explored as strategy for the intended VCT program in this district.
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Affiliation(s)
- Frank Baiden
- Navrongo Health Research Center, Navrongo, Ghana.
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Abstract
The structure of the mixed p(3 x 3)-(3OH + 3H2O) phase on Pt[111] has been investigated by low-energy electron diffraction-IV structure analysis. The OH + H2O overlayer consists of hexagonal rings of coplanar oxygen atoms interlinked by hydrogen bonds. Lateral shifts of the O atoms away from atop sites result in different O-O separations and hexagons with only large separations (2.81 and 3.02 angstroms) linked by hexagons with alternating separations of 2.49 and 2.813.02 angstroms. This unusual pattern is consistent with a hydrogen-bonded network in which water is adsorbed in cyclic rings separated by OH in a p(3 x 3) structure. The top-most two layers of the Pt atoms relax inwards with respect to the clean surface and both show vertical buckling of up to 0.06 angstroms. In addition, significant shifts away from the lateral bulk positions have been found for the second layer of Pt atoms.
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Affiliation(s)
- G Held
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
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Abstract
ICRP dose coefficients for the ingestion of organically bound tritium (OBT) by adults and children are intended for general application to unspecified forms in diet and may not be applicable to intakes of a specific form of OBT. To obtain information relating to OBT in fish from Cardiff Bay, the retention of tritium in adult rats was determined after administration as either tritiated water (HTO) or dried flounder flesh containing OBT. Two components of retention were obtained in each case. The first component, attributable to tritium equilibrating with body water, had a half-time of retention of 3 days in each case, and accounted for 97% of the intake as HTO and 70% after intake of OBT in flounder. Results were consistent with rapid catabolism of a large proportion of flounder OBT to HTO. The second component of retention, attributable to OBT in rat tissues, accounted for 3% of tritium intake as HTO and 30% after intake as flounder OBT; the half-times of retention were 10 days and 25 days, respectively. The results obtained after administration as HTO are consistent with published animal data and correlate with the ICRP assumptions for adult man of half-times of 10 days for 97% behaving as HTO in body tissues and 40 days for 3% incorporated into OBT in body tissues. The results obtained after administration of flounder OBT suggest that appropriate assumptions for retention in adult man are 70% with a 10 day half-time and 30% with a 100 day half-time. These assumptions result in an ingestion dose coefficient of 6 x 10(-11) Sv Bq(-1). This compares with the ICRP value for OBT ingestion by adults of 4.2 x 10(-11) Sv Bq(-1), based on half-times of 10 days and 40 days applied to equal proportions of retained tritium. It is proposed that a dose coefficient of 6 x 10(-11) Sv Bq(-1) should be applied to tritium in flounders from Cardiff Bay. It is further proposed that this dose coefficient should be applied to all ingestion intakes by adults relating to this source of exposure, unless specific information is available showing that a significant proportion of the intake is HTO. The same proposals apply to dose coefficients derived here for flounder OBT consumption by children.
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Affiliation(s)
- A Hodgson
- Health Protection Agency, Radiation Protection Division, Chilton, Didcot, Oxon OX11 0RQ, UK.
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Abstract
The stability of OH on Pt(111) has been investigated to determine the role of hydrogen bonding in stabilizing the overlayer. We find that the optimal structure is a mixed (OH+H2O) phase, confirming recent density-functional theory predictions. The reaction O+3H(2)O forms a hexagonal (sqrt[3]xsqrt[3])R30 degrees -(OH+H2O) lattice with a weak (3x3) superstructure, caused by ordering of the hydrogen bonds. The mixed overlayer can accommodate a range of H(2)O/OH compositions but becomes less stable as the H2O content is reduced, causing defects in the hydrogen-bonding network that lift the (3 x 3) superstructure and destabilize the overlayer.
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Affiliation(s)
- C Clay
- Surface Science Research Centre, The University of Liverpool, Liverpool L69 3BX, United Kingdom
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Willbrand TC, Hodgson A, Clanton DJ, Ho RJ, Wenner CA. 351 DIFFERENTIAL ANTI-HIV ACTIVITY OF DISTINCT HYDROALCOHOLIC HYPERICUM PERFORATUM PREPARATIONS. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Farcas A, Hodgson A, Finnell JS, Fry J, Cech N, Sivam G, Wenner CA. 400 IMMUNOMODULATORY ACTIVITY OF ECHINACEA PURPUREA EXTRACTS PREPARED IN A SERIES OF ETHANOL:WATER MENSTRUUMS ON HUMAN MONOCYTE/MACROPHAGE CELL LINES. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Bailey MR, Ansoborlo E, Chazel V, Fritsch P, Hodgson A, Kreyling WG, Le Gall B, Newton D, Paquet F, Stradling N, Svartengren M, Taylor DM, Wenman-Bateson S. Radionuclide biokinetics database (RBDATA-EULEP): an update. Radiat Prot Dosimetry 2004; 112:535-536. [PMID: 15623891 DOI: 10.1093/rpd/nch098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The main activity of the RBDATA-EULEP project is the development of an electronic database of information on the biokinetics of radionuclides after intake by inhalation, ingestion or injection. It consists of linked tables of publications and experiments, with details and comments on the materials, procedures and results. By March 2004 it contained information on more than 1600 experiments from 600 publications. It will be extended and Internet access will also be provided.
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Affiliation(s)
- M R Bailey
- National Radiological Protection Board, Chilton, Didcot, Oxon OX11 0RQ, UK.
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Pellow PGD, Hodgson SA, Hodgson A, Rance E, Ellender M, Guilmette RA, Stradling GN. Comparison of absorption after inhalation and instillation of uranium octoxide. Radiat Prot Dosimetry 2003; 105:105-108. [PMID: 14526937 DOI: 10.1093/oxfordjournals.rpd.a006202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Values for the absorption parameters were compared after inhalation or intratracheal instillation of 1.5 microm mass median aerodynamic diameter (MMAD) 233U3O8 particles into the lungs of HMT strain rats. The two sets of parameter values were similar, as were the calculated dose coefficients and predicted biokinetics for workers. Hence the inhalation and instillation techniques can probably both be used to generate values of the absorption parameters for U3O8.
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Affiliation(s)
- P G D Pellow
- National Radiological Protection Board, Chilton, Didcot, Oxon OX11 0RQ, UK.
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