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O’Brien G, Glenn K, Lawrence G, Williams A, Webster M, Burns S, Cowley R. INFLUENCE OF HYDROCARBON MIGRATION AND SEEPAGE ON BENTHIC COMMUNITIES IN THE TIMOR SEA, AUSTRALIA. ACTA ACUST UNITED AC 2002. [DOI: 10.1071/aj01013] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The Ashmore Platform–Timor Sea region of Australia’s North West Shelf is an area of significant petroleum exploration potential, with several large commercial oil fields present. Moreover, exploration activity seems likely to continue at current levels for the foreseeable future, and may also extend into deeper water, given high oil prices and improved drilling technologies. The area is also one of high conservation value, with both the Cartier Marine reserve and Ashmore Reef (a Category 1 marine park), as well as numerous other genetically-rich carbonate seed bank systems, closely associated spatially with exploration activities. Balancing the conservation and resource values in this area will present a key challenge into the future.The magnitude of this challenge has been highlighted by recent work undertaken by AGSO, which involved the acquisition and interpretation of assorted remote sensing data, such as high-resolution bathymetry (including sidescan sonar), satellite synthetic aperture radar (SAR), Landsat, water column geochemical sniffer, airborne laser fluorosensor, seismic data and seafloor sediment sampling. These studies have shown that, at both a regional and local scale, the development of these important carbonate systems appears to directly relate to the geological development of the area.At a regional scale, the collision between the Australian and Eurasian crustal plates in the Pliocene (At a local scale, new data also strongly suggest that the locations of the majority of reefs and carbonate banks and build-ups in the area are associated with active and palaeo-hydrocarbon seeps. These seeps are localised over either fault systems which tap the reservoir, along migration fairways, or at the pinch-out of the regional Cretaceous top seal. Our interpretations suggest that the reefs and the build-ups formed by a sequential process. Firstly, hydrocarbon seepage (induced by collisionrelated faulting) localised small seafloor (chemolithotrophic) biological carbonate communities, which ultimately formed topographically positive features. These higher relief features were subsequently preferentially colonised by an assortment of reef-building biota, whose rapid growth progressively kept up with rising sea-level (which was driven principally by collisionrelated subsidence). The most favourable conditions for initial reef colonisation probably occurred during periods of relatively low sea-level, when the areas around the reefs were located at much shallower water depths (Clearly, the fact that the genetically rich carbonate communities in this area are probably causally related to natural hydrocarbon seepage (and the attendant processes which drove that seepage) will present a series of almost unique exploration, development (especially engineering) and conservation challenges.
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Burns S. Beyond best practices: knowledge management. HEALTHCARE BENCHMARKS 2001; 8:129-31. [PMID: 11721618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Burns S, Thrasher AJ, Blundell MP, Machesky L, Jones GE. Configuration of human dendritic cell cytoskeleton by Rho GTPases, the WAS protein, and differentiation. Blood 2001; 98:1142-9. [PMID: 11493463 DOI: 10.1182/blood.v98.4.1142] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The cellular mechanisms that configure the cytoskeleton during migration of dendritic cells (DCs) are poorly understood. Immature DCs assemble specialized adhesion structures known as podosomes at their leading edge; these are associated with the localized recruitment of the Wiskott-Aldrich Syndrome protein (WASp) and the actin organizing actin-related protein 2/3 complex. In immature DCs lacking WASp, podosomes are absent, residual dysmorphic lamellipodia and filopodia are nonpolarized, and migration is severely compromised. Microinjection studies indicate that podosome assembly and polarization require concerted action of Cdc42, Rac, and Rho, thereby providing a link between sequential protrusive and adhesive activity. Formation of podosomes is restricted to cells with an immature phenotype, indicating a specific role for these structures during the early migratory phase. (Blood. 2001;98:1142-1149)
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Strebel P, Nordin J, Edwards K, Hunt J, Besser J, Burns S, Amundson G, Baughman A, Wattigney W. Population-based incidence of pertussis among adolescents and adults, Minnesota, 1995-1996. J Infect Dis 2001; 183:1353-9. [PMID: 11294666 DOI: 10.1086/319853] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2000] [Revised: 02/07/2001] [Indexed: 11/03/2022] Open
Abstract
To estimate the incidence of pertussis, a prospective study was done among members of a managed care organization in Minneapolis/St. Paul, Minnesota. Of 212 patients 10-49 years old enrolled from January 1995 through December 1996, 8 were found to be culture positive, 10 were found to be positive by polymerase chain reaction assay, 13 had a > or =2-fold increase in IgG or IgA to pertussis toxin (PT), and 18 had IgG to PT in a single serum specimen > or =3 SD above the mean of an age-matched control group. At least 1 positive laboratory test result for pertussis infection was found in 27 (13%) patients, among whom the duration of cough illness was a median of 42 days (range, 27-66 days). On the basis of any positive laboratory result, the estimated annual incidence of pertussis was 507 cases per 100,000 person-years (95% confidence interval, 307-706 cases). Bordetella pertussis infection may be a more common cause of cough illness among adolescents and adults than was recognized previously.
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Calvert JT, Burns S, Riney TJ, Sahoo T, Orlow SJ, Nevin NC, Haisley-Royster C, Prose N, Simpson SA, Speer MC, Marchuk DA. Additional glomangioma families link to chromosome 1p: no evidence for genetic heterogeneity. Hum Hered 2001; 51:180-2. [PMID: 11173970 DOI: 10.1159/000053340] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Venous malformations are a common abnormality of the vasculature that may occur sporadically or, more rarely, as an autosomal dominant trait. One familial form of venous malformations has previously been linked to chromosome 9p. Mutations in the gene encoding Tie2, an endothelial specific receptor tyrosine kinase, have been identified in four different families. Glomangiomas are a subtype of venous malformations with glomus cell involvement. These cutaneous lesions can be inherited as an autosomal dominant disease with reduced penetrance and variable expressivity. We present evidence of linkage to chromosome 1p21-1p22 using four new glomangioma families, with a combined maximum two-point lod score of 7.32 at marker D1S2804. Markers D1S2129 and D1S2881 define the 24-cM linkage interval determined by recombination within affected individuals. A recent report also showed linkage of the glomangioma locus to chromosome 1p. A total of 9 families now map to this region, suggesting a decreased likelihood of locus heterogenity in familial glomangiomas. Investigation of candidate genes within the interval should provide new insights into lesion formation in inherited venous malformations.
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Goldberg D, Cameron S, Sharp G, Burns S, Scott G, Molyneaux P, Scoular A, Downie A, Taylor A. Hepatitis C virus among genitourinary clinic attenders in Scotland: unlinked anonymous testing. Int J STD AIDS 2001. [DOI: 10.1258/0956462011916686] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Hoare SF, Bryce LA, Wisman GB, Burns S, Going JJ, van der Zee AG, Keith WN. Lack of telomerase RNA gene hTERC expression in alternative lengthening of telomeres cells is associated with methylation of the hTERC promoter. Cancer Res 2001; 61:27-32. [PMID: 11196173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The immortal phenotype of most human cancers is attributable to telomerase expression. However, a number of immortal cell lines and tumors achieve telomere maintenance in the absence of telomerase via alternative mechanisms known as ALT (alternative lengthening of telomeres). Here we show that the promoter of the telomerase RNA gene (hTERC) is methylated in three of five ALT cell lines and is associated with a total absence of hTERC expression in the three lines. Treatment with 5-azacytidine in combination with trichostatin A resulted in partial demethylation of the hTERC promoter and expression of the gene. Partial methylation was detected in tumors (5%) and in immortal cell lines (27%). Cell lines with partial methylation express hTERC. Only in ALT cell lines does there appear to be a strong correlation between hTERC promoter hypermethylation and lack of hTERC expression.
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Burns S. Benchmarking: beating the information explosion. HEALTHCARE BENCHMARKS 2001; 8:9-11. [PMID: 11481902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
What could possibly be more intriguing for health care professionals than access to comparative data, of all types, for use at any time? The only fantasy more engaging would be having the information and actually being able to use it constructively.
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Burns S. How medical managers avoid mindsets that are minefields. MANAGED CARE (LANGHORNE, PA.) 2001; 10:29-30, 33. [PMID: 11211327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Goldberg D, Cameron S, Sharp G, Burns S, Scott G, Molyneaux P, Scoular A, Downie A, Taylor A. Hepatitis C virus among genitourinary clinic attenders in Scotland: unlinked anonymous testing. Int J STD AIDS 2001; 12:17-21. [PMID: 11177477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Our objective is to gauge the prevalence of hepatitis C virus (HCV) antibodies among a population at risk of contracting sexually transmitted infections (STIs) and, thus, the efficiency with which the virus is transmitted sexually. The investigators undertook an unlinked anonymous HCV antibody testing study of residual syphilis serology specimens taken from attenders of genitourinary clinics in Glasgow, Edinburgh and Aberdeen during 1996/97. The results were linked to non-identifying risk information. Anti-HCV prevalences among non-injecting heterosexual men and women, and non-injecting homosexual/bisexual males ranged between 0 and 1.2%; the only exception to this was a 7.7% (4/52) prevalence among homosexual/bisexual males in Aberdeen. The overall anti-HCV prevalence for homosexual/bisexual males was 0.6% (4/668), for heterosexual males 0.8% (32/4135), for heterosexual females 0.3% (10/3035) and for injecting drug users 49% (72/148). Only 3 (all female) of the 46 non-injectors who were antibody positive were non-UK nationals or had lived abroad. HCV antibody positive injectors were less likely to have an acute STI and more likely to know their HCV status than non-injectors; no differences in these parameters were found between positive and negative non-injectors on anonymous HCV antibody testing. Our findings are in keeping with the prevailing view that HCV can be acquired through sexual intercourse but, for most people, the probability of this occurring is extremely low. Interventions to prevent the spread of HCV should be targeted mainly at injecting drug user (IDU) populations.
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Thrasher AJ, Burns S, Lorenzi R, Jones GE. The Wiskott-Aldrich syndrome: disordered actin dynamics in haematopoietic cells. Immunol Rev 2000; 178:118-28. [PMID: 11213796 DOI: 10.1034/j.1600-065x.2000.17803.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The Wiskott-Aldrich syndrome protein (WASp) is a member of a unique family whose members share similar domain structures and are responsible for the transduction of signals from the cell membrane to the actin cytoskeleton. For WASp, the interactions with Rho family GTPases and the cytoskeletal organising complex Arp2/3 are critical to these functions, which when disturbed translate into abnormalities of haematopoietic cell signaling, polarisation, migration and phagocytosis. This review discusses the evidence for regulation of highly dynamic cytoskeletal structures by WASp and the consequences of disturbed function on some of these processes.
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Matrician L, Ange G, Burns S, Fanning WL, Kioski C, Cage GD, Komatsu KK. Outbreak of nosocomial Burkholderia cepacia infection and colonization associated with intrinsically contaminated mouthwash. Infect Control Hosp Epidemiol 2000; 21:739-41. [PMID: 11089663 DOI: 10.1086/501719] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
From August 1996 through June 1998, 69 ventilated, intensive care unit patients at two Arizona hospitals had nosocomial respiratory tract cultures positive for Burkholderia cepacia. Intrinsically contaminated alcohol-free mouthwash was identified by pulsed-field gel electrophoresis as the source of the outbreak.
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Elsner A, Miura M, Burns S, Beausencourt E, Kunze C, Kelley L, Walker J, Wing G, Raskauskas P, Fletcher D, Zhou Q, Dreher A. Multiply scattered light tomography and confocal imaging: detecting neovascularization in age-related macular degeneration. OPTICS EXPRESS 2000; 7:95-106. [PMID: 19404374 DOI: 10.1364/oe.7.000095] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A novel technique, Multiply Scattered Light Tomography (MSLT), and confocal Infrared Imaging are used to provide diagnostic information using a comfortable, rapid, and noninvasive method. We investigated these techniques in detecting neovascularization in age-related macular degeneration. The MSLT used a Vertical Cavity Surface Emitting Laser (VCSEL) at 850 nm, while the confocal imaging technique used either the VCSEL or a 790 nm laser diode. Both were implemented into the topographical scanning system (TopSS, Laser Diagnostic Technologies, Inc.) Confocal imaging with both lasers provided different information about neovascularization as a function of focal plane, and different also from MSLT.
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Quigg M, Harris D, Precious H, Clutterbuck D, Nicoll S, Burns S, McMillan A, Leen C, Brown AL. O6 Genotypic resistance mutations and virological response to combination therapy in a clinical cohort. HIV Med 2000. [DOI: 10.1046/j.1468-1293.2000.00024-11.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Elsner A, Moraes L, Beausencourt E, Remky A, Weiter J, Walker J, Wing G, Burns S, Raskauskas P, Kelley L. Scanning laser reflectometry of retinal and subretinal tissues. OPTICS EXPRESS 2000; 6:243-250. [PMID: 19404357 DOI: 10.1364/oe.6.000243] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Measurements of the human ocular fundus that make use of the light returning through the pupil are called reflectometry. Early reflectometry studies were limited by poor light return from the retina and strong reflections from the anterior surface of the eye. Artifacts produced misleading results in diseases like age-related macular degeneration. Novel laser sources, scanning, confocal optics, and digital imaging provide improved sampling of the signal from the tissues of interest: photoreceptors and retinal pigment epithelial cells. A wider range of wavelengths is now compared, including the near infrared. Reflectometry now provides functional mapping, even in severe pathology.
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Cross D, Stevenson M, Hall M, Burns S, Laughlin D, Officer J, Howat P. Child pedestrian injury prevention project: student results. Prev Med 2000; 30:179-87. [PMID: 10684740 DOI: 10.1006/pmed.1999.0622] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Few comprehensive pedestrian safety interventions for primary-school-age children have been developed and evaluated. This paper reports the impact of the 3-year (1995-1997) Child Pedestrian In jury Prevention Project (CPIPP) on a cohort of 1603 children followed from age 6 to 9 years. This multicomponent project comprised an educational intervention for students, their parents and teachers, and the local community, as well as several environmental interventions. The primary aim of CPIPP was to improve children's road-related behavior and to enhance the safety of their road environment. METHODS Three communities were assigned to the treatment conditions: (1) high-education, community, and environmental interventions; (2) moderate-education intervention only; and (3) comparison (usual road safety education). Children's pedestrian knowledge and road crossing and playing behaviors were assessed using a pre- and posttest self-report questionnaire. Their self-reported road crossing behaviors were validated using an observational schedule and brief interview. RESULTS Children in the high and moderate intervention groups were significantly more likely to cross the road with adult supervision (P = 0.013) and play away from the road (P = 0.000) than the comparison group. No differences were detected in children's pedestrian safety knowledge between the intervention and comparison groups. CONCLUSIONS While several methodological limitations may have influenced the study outcomes, these data nonetheless indicate that in the study sample the CPIPP educational intervention deaccelerated the natural increase in children's pedestrian-related risk behavior.
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O'Brien G, Lawrence G, Williams A, Webster M, Wilson D, Burns S. USING INTEGRATED REMOTE SENSING TECHNOLOGIES TO EVALUATE AND CHARACTERISE HYDROCARBON MIGRATION AND CHARGE CHARACTERISTICS ON THE YAMPI SHELF, NORTHWESTERN AUSTRALIA: A METHODOLOGICAL STUDY. ACTA ACUST UNITED AC 2000. [DOI: 10.1071/aj99013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
As part of a major interpretative study of the Yampi Shelf, northeastern Browse Basin, the Australian Geological Survey Organisation (AGSO) acquired regional seismic, water column geochemical sniffer (WaSi), RadarSat Synthetic Aperture Radar (SAR), and high resolution bathymetric data over the area between 1995 and 1998. These data have been integrated in order to better understand both the hydrocarbon charge and top seal capacity characteristics of the area, and the relative responses of assorted remote sensing technologies to hydrocarbon migration, leakage and seepage. The area investigated comprises part of a Palaeozoic to Mesozoic flexural ramp margin, which dips northwest away from the flanking cratonic Kimberley Block. The basement has a rugose topography, with some horst blocks elevated 500 m above the surrounding basement. Progressive onlap of Cretaceous post-rift seals onto the ramp causes the regional seal to become thinner and sandier margin- ward. In some of these more margin-ward locations, some prominent basement highs are 'bald' of seal, whereas in others, the seal thins dramatically onto topographically prominent, landward-dipping tilt blocks. Natural hydrocarbon seepage was confirmed independently by SAR and WaSi, though the relative response and sensitivity of each technology to seepage of varying rates and compositions are quite different. Overall, the principal seeping hydrocarbon is dry (
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Burns S, Nelson L, Maguire P, Dunn G, Desai M, Kitchener H. Patient choice in the management of mild dyskaryosis. Int J Gynaecol Obstet 2000. [DOI: 10.1016/s0020-7292(00)82640-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Abstract
The Wiskott-Aldrich Syndrome (WAS) is a rare inherited X-linked recessive disease characterised by immune dysregulation and microthrombocytopenia. Recently, the biological mechanisms that are responsible for the pathophysiology of WAS have been shown to be linked to the regulation of the actin cytoskeleton in haematopoietic cells. The WAS protein (WASp) is now known to be a member of a unique family that share similar domain structures, and that are responsible for transduction of signals from the cell membrane to the actin cytoskeleton. The interactions between WASp, the Rho family GTPase Cdc42, and the cytoskeletal organising complex Arp2/3 are probably critical to many of these functions, which, when disturbed, translate into measurable defects of cell polarisation and motility.
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Schofield PM, Sharples LD, Caine N, Burns S, Tait S, Wistow T, Buxton M, Wallwork J. Transmyocardial laser revascularisation in patients with refractory angina: a randomised controlled trial. Lancet 1999; 353:519-24. [PMID: 10028979 DOI: 10.1016/s0140-6736(98)11478-2] [Citation(s) in RCA: 278] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Transmyocardial laser revascularisation (TMLR) is used to treat patients with refractory angina due to severe coronary artery disease, not suitable for conventional revascularisation. We aimed in a randomised controlled trial to assess the effectiveness of TMLR compared with medical management. METHODS 188 patients with refractory angina were randomly assigned TMLR plus normal medication or medical management alone. At 3 months, 6 months, and 12 months after surgery (TMLR) or initial assessment (medical management) we assessed exercise capacity with the treadmill test and the 12 min walk. FINDINGS Mean treadmill exercise time, adjusted for baseline values, was 40 s (95% CI -15 to 94) longer in the TMLR group than in the medical-management group at 12 months (p=0.152). Mean 12 min walk distance was 33 m (-7 to 74) further in TMLR patients than medical-management patients (p=0.108) at 12 months. The differences were not significant or clinically important. Perioperative mortality was 5%. Survival at 12 months was 89% (83-96) in the TMLR group and 96% (92-100) in the medical-management group (p=0.14). Canadian Cardiovascular Society score for angina had decreased by at least two classes in 25% of TMLR and 4% of medical-management patients at 12 months (p<0.001). INTERPRETATION Our findings show that the adoption of TMLR cannot be advocated. Further research may be appropriate to assess any potential benefit for sicker patients.
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Dahmani F, Schmid AW, Lambropoulos JC, Burns S. Dependence of birefringence and residual stress near laser-induced cracks in fused silica on laser fluence and on laser-pulse number. APPLIED OPTICS 1998; 37:7772-7784. [PMID: 18301617 DOI: 10.1364/ao.37.007772] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Measurements of birefringence induced in fused-silica specimens by a crack produced by a 351-nm/500-ps Nd:glass laser as a function of laser fluence F(L) and of number of laser shots N are presented. The varying dimensional parameter is found to be the crack depth a and can be put in the form a(mm) = (0.0096 ? 0.0021)N[(F(L)/F(exit/th)) - 1](2/3) with F(L) >/= F(exit/th)(F(exit/th) is the exit-surface damage threshold). The retardance data are converted into units of stress, thus permitting the estimation of residual stress near the crack. The results of the measured residual stress can be cast in the form varsigma(r)(MPa) approximately (. ? .)[(F(L)/F(exit/th)) - 1](1/2) N(2/3) with F(L)>/= F(exit/th). A theoretical model giving the stress field around a crack is developed for comparison and shows reasonable agreement with the experiment. Good agreement with experimental data of others is also obtained. The effect of residual stresses on fracture strength is pointed out. The results obtained show that the presence of birefringence/residual stress in a fused-silica specimen with a crack on its surface has a strong effect on fracture and should be taken into account in any formulation that involves the failure strength of optical components used in inertial-confinement-fusion experiments.
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Johnstone F, Goldberg D, Tappin D, Mathie L, Cameron S, Brown A, Burns S, Hamilton B, Codere G, Girdwood RW. The incidence and prevalence of HIV infection among childbearing women living in Edinburgh city, 1982-1995. AIDS 1998; 12:911-8. [PMID: 9631145 DOI: 10.1097/00002030-199808000-00014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To track the complete course of the HIV epidemic among women from the city of Edinburgh who delivered babies during 1982-1995. METHODS The performance of the modified Serodia HIV test on dried blood spots from archived neonatal metabolic screening cards stored for up to 11 years was evaluated by testing 221 cards from neonates whose mothers' HIV infection status was already known (100 HIV-positive, 121 HIV-negative). Unlinked anonymous HIV testing of cards from neonates born during 1982-1989 was then performed and the resulting prevalence data were combined with existing data from 1990-1995. Maximum and minimum limits of HIV incidence among women during the 36-month period prior to delivery were calculated using data held on a clinical database of HIV-infected pregnant women that had been generated under strict conditions of confidentiality; these data included the date of the woman's first HIV-positive and, if available, last HIV-negative specimen. RESULTS The evaluation revealed a sensitivity of 91%, not clearly related to storage time, and a specificity of 100%. HIV infection first entered Edinburgh's childbearing population during the early 1980s with prevalence peaking at 0.4% in 1986 and then decreasing to 0.1% in 1995; a similar incidence profile was seen during this period. Since 1986, the first full year that HIV testing was available, 78% of all infections were known during the pregnancy, 13% were identified retrospectively, and only 10% (10 cases) remain unaccounted for. For infected cases during 1984-1987, 78% were injecting drug users (IDU) and only 22% acquired their infection sexually; this distribution had reversed by 1992-1995. CONCLUSION HIV testing of neonatal metabolic screening cards stored for up to 11 years can yield results of sufficient accuracy for epidemiological purposes. There has been a substantial decline in the prevalence and incidence of HIV since the mid-1980s. Although new infections are still occurring, the numbers are small. The decline may largely be explained by the impact of preventive measures on the spread of HIV amongst IDU, and thus from IDU to their sexual partners.
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Knebel A, Shekleton ME, Burns S, Clochesy JM, Hanneman SK. Weaning from mechanical ventilatory support: refinement of a model. Am J Crit Care 1998. [DOI: 10.4037/ajcc1998.7.2.149] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The American Association of Critical-Care Nurses sponsored the third National Study Group to advance the science of weaning from mechanical ventilatory support and to guide clinical practice. The study group proposed a model of weaning in 1994 to provide an organizing framework for scientific inquiry. Since the model was first proposed, the ongoing work of the study group has led to refinement of the model. The purpose of this brief communication is to inform critical care clinicians and researchers about the refinements.
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Knebel A, Shekleton ME, Burns S, Clochesy JM, Hanneman SK. Weaning from mechanical ventilatory support: refinement of a model. Am J Crit Care 1998; 7:149-52. [PMID: 9509229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The American Association of Critical-Care Nurses sponsored the third National Study Group to advance the science of weaning from mechanical ventilatory support and to guide clinical practice. The study group proposed a model of weaning in 1994 to provide an organizing framework for scientific inquiry. Since the model was first proposed, the ongoing work of the study group has led to refinement of the model. The purpose of this brief communication is to inform critical care clinicians and researchers about the refinements.
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Burns S, Burns JL. The genesis of physical culture in America. J Altern Complement Med 1997; 2:461-2. [PMID: 9395675 DOI: 10.1089/acm.1996.2.461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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