| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
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| 3. |
- Ng, M Y M, et al.
(författare)
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Meta-analysis of 32 genome-wide linkage studies of schizophrenia
- 2009
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Ingår i: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 14:8, s. 774-785
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Tidskriftsartikel (refereegranskat)abstract
- A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (P(SR)) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for 'aggregate' genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies.
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| 4. |
- Clark, Andrew G., et al.
(författare)
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Evolution of genes and genomes on the Drosophila phylogeny
- 2007
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 450:7167, s. 203-218
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Tidskriftsartikel (refereegranskat)abstract
- Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species.
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| 5. |
- Haas, Brian J., et al.
(författare)
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Genome sequence and analysis of the Irish potato famine pathogen Phytophthora infestans
- 2009
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 461:7262, s. 393-398
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Tidskriftsartikel (refereegranskat)abstract
- Phytophthora infestans is the most destructive pathogen of potato and a model organism for the oomycetes, a distinct lineage of fungus-like eukaryotes that are related to organisms such as brown algae and diatoms. As the agent of the Irish potato famine in the mid-nineteenth century, P. infestans has had a tremendous effect on human history, resulting in famine and population displacement(1). To this day, it affects world agriculture by causing the most destructive disease of potato, the fourth largest food crop and a critical alternative to the major cereal crops for feeding the world's population(1). Current annual worldwide potato crop losses due to late blight are conservatively estimated at $6.7 billion(2). Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars(3,4). Here we report the sequence of the P. infestans genome, which at similar to 240 megabases (Mb) is by far the largest and most complex genome sequenced so far in the chromalveolates. Its expansion results from a proliferation of repetitive DNA accounting for similar to 74% of the genome. Comparison with two other Phytophthora genomes showed rapid turnover and extensive expansion of specific families of secreted disease effector proteins, including many genes that are induced during infection or are predicted to have activities that alter host physiology. These fast-evolving effector genes are localized to highly dynamic and expanded regions of the P. infestans genome. This probably plays a crucial part in the rapid adaptability of the pathogen to host plants and underpins its evolutionary potential.
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| 6. |
- Lindblad-Toh, Kerstin, et al.
(författare)
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Genome sequence, comparative analysis and haplotype structure of the domestic dog.
- 2005
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 438:7069, s. 803-19
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Tidskriftsartikel (refereegranskat)abstract
- Here we report a high-quality draft genome sequence of the domestic dog (Canis familiaris), together with a dense map of single nucleotide polymorphisms (SNPs) across breeds. The dog is of particular interest because it provides important evolutionary information and because existing breeds show great phenotypic diversity for morphological, physiological and behavioural traits. We use sequence comparison with the primate and rodent lineages to shed light on the structure and evolution of genomes and genes. Notably, the majority of the most highly conserved non-coding sequences in mammalian genomes are clustered near a small subset of genes with important roles in development. Analysis of SNPs reveals long-range haplotypes across the entire dog genome, and defines the nature of genetic diversity within and across breeds. The current SNP map now makes it possible for genome-wide association studies to identify genes responsible for diseases and traits, with important consequences for human and companion animal health.
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| 7. |
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| 8. |
- Ferwerda, Bart, et al.
(författare)
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Functional and genetic evidence that the Mal/TIRAP allele variant 180L has been selected by providing protection against septic shock.
- 2009
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 106:25, s. 10272-10277
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Tidskriftsartikel (refereegranskat)abstract
- Adequate responses by our innate immune system toward invading pathogens were of vital importance for surviving infections, especially before the antibiotic era. Recently, a polymorphism in Mal (Ser180Leu, TIRAP rs8177374), an important adaptor protein downstream of the Toll-like receptor (TLR) 2 and 4 pathways, has been described to provide protection against a broad range of infectious pathogens. We assessed the functional effects of this polymorphism in human experimental endotoxemia, and we demonstrate that individuals bearing the TIRAP 180L allele display an increased, innate immune response to TLR4 and TLR2 ligands, but not to TLR9 stimulation. This phenotype has been related to an increased resistance to infection. However, an overshoot in the release of proinflammatory cytokines by TIRAP 180L homozygous individuals suggests a scenario of balanced evolution. We have also investigated the worldwide distribution of the Ser180Leu polymorphism in 14 populations around the globe to correlate the genetic makeup of TIRAP with the local infectious pressures. Based on the immunological, clinical, and genetic data, we propose that this mutation might have been selected in West Eurasia during the early settlement of this region after the out-of-Africa migration of modern Homo sapiens. This combination of functional and genetic data provides unique insights to our understanding of the pathogenesis of sepsis.
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| 9. |
- Kaptoge, S., et al.
(författare)
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Whom to treat? The contribution of vertebral X-rays to risk-based algorithms for fracture prediction. Results from the European Prospective Osteoporosis Study
- 2006
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Ingår i: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 17:9, s. 1369-1381
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Vertebral fracture is a strong risk factor for future spine and hip fractures; yet recent data suggest that only 5-20% of subjects with a spine fracture are identified in primary care. We aimed to develop easily applicable algorithms predicting a high risk of future spine fracture in men and women over 50 years of age. Methods: Data was analysed from 5,561 men and women aged 50+ years participating in the European Prospective Osteoporosis Study (EPOS). Lateral thoracic and lumbar spine radiographs were taken at baseline and at an average of 3.8 years later. These were evaluated by an experienced radiologist. The risk of a new (incident) vertebral fracture was modelled as a function of age, number of prevalent vertebral fractures, height loss, sex and other fracture history reported by the subject, including limb fractures occurring between X-rays. Receiver Operating Characteristic (ROC) curves were used to compare the predictive ability of models. Results: In a negative binomial regression model without baseline X-ray data, the risk of incident vertebral fracture significantly increased with age [RR 1.74, 95% CI (1.44, 2.10) per decade], height loss [1.08 (1.04, 1.12) per cm decrease], female sex [1.48 (1.05, 2.09)], and recalled fracture history; [1.65 (1.15, 2.38) to 3.03 (1.66, 5.54)] according to fracture site. Baseline radiological assessment of prevalent vertebral fracture significantly improved the areas subtended by ROC curves from 0.71 (0.67, 0.74) to 0.74 (0.70, 0.77) P=0.013 for predicting 1+ incident fracture; and from 0.74 (0.67, 0.81) to 0.83 (0.76, 0.90) P=0.001 for 2+ incident fractures. Age, sex and height loss remained independently predictive. The relative risk of a new vertebral fracture increased with the number of prevalent vertebral fractures present from 3.08 (2.10, 4.52) for 1 fracture to 9.36 (5.72, 15.32) for 3+. At a specificity of 90%, the model including X-ray data improved the sensitivity for predicting 2+ and 1+ incident fractures by 6 and 4 fold respectively compared with random guessing. At 75% specificity the improvements were 3.2 and 2.4 fold respectively. With the modelling restricted to the subjects who had BMD measurements (n=2,409), the AUC for predicting 1+ vs. 0 incident vertebral fractures improved from 0.72 (0.66, 0.79) to 0.76 (0.71, 0.82) upon adding femoral neck BMD (P=0.010). Conclusion: We conclude that for those with existing vertebral fractures, an accurately read spine X-ray will form a central component in future algorithms for targeting treatment, especially to the most vulnerable. The sensitivity of this approach to identifying vertebral fracture cases requiring anti-osteoporosis treatment, even when X-rays are ordered highly selectively, exceeds by a large margin the current standard of practice as recorded anywhere in the world.
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| 10. |
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| 11. |
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| 12. |
- Macfarlane, G. J., et al.
(författare)
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Investigating the determinants of international differences in the prevalence of chronic widespread pain: evidence from the European Male Ageing Study
- 2009
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 68:5, s. 690-695
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To determine whether among middle-aged and elderly men there is evidence of international differences in the prevalence of chronic widespread pain (CWP) and whether any such differences could be explained by psychological, psychosocial factors or differences in physical health status. Methods: The European Male Ageing Study (EMAS) sampled from population registers in cities ( centres) of eight European countries. Each centre recruited an age-stratified sample of men aged 40-79 years. Information on pain was collected by questionnaire and subjects were classified according to whether they satisfied the American College of Rheumatology definition of CWP. Information was collected on social status, mental health, recent life events and co-morbidities. Results: Across all centres 3963 subjects completed a study questionnaire, with participation rates ranging from 24% in Hungary to 72% in Estonia. There were significant differences in prevalence: between 5% and 7% in centres in Italy, England, Belgium and Sweden, 9-15% in centres in Spain, Poland and Hungary and 15% in Estonia. There were strong relationships between poor mental health, adverse recent life events, co-morbidities and CWP. Adjustment for these factors explained between half and all of the excess risk in the eastern European centres: the excess risk in Poland was explained ( odds ratio ( OR) 1.1, 95% CI 0.9 to 1.2) but there remained excess risk in Hungary ( OR 1.6, 95% CI 1.4 to 1.8) and Estonia ( OR 2.6, 95% CI 2.2 to 2.9). Conclusions: This study is the first directly to compare the occurrence of CWP internationally. There is an excess prevalence in countries of eastern Europe and this excess is associated with adverse psychosocial factors as well as poorer psychological and physical health.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Lee, David M., et al.
(författare)
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Association between 25-hydroxyvitamin D levels and cognitive performance in middle-aged and older European men
- 2009
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Ingår i: Journal of Neurology, Neurosurgery and Psychiatry. - : BMJ. - 1468-330X .- 0022-3050. ; 80:7, s. 722-729
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Tidskriftsartikel (refereegranskat)abstract
- Background: Although there is evidence that vitamin D inadequacy may be linked to adverse cognitive outcomes, results from studies on this topic have been inconsistent. The aim of this trial was to examine the association between 25-hydroxyvitamin D (25(OH) D) levels and cognitive performance in middle-aged and older European men. Methods: This population-based cross-sectional study included 3,369 men aged 40-79 years from eight centres enrolled in the European Male Ageing Study. Cognitive function was assessed using the Rey-Osterrieth Complex Figure (ROCF) test, the Camden Topographical Recognition Memory (CTRM) test and the Digit Symbol Substitution Test (DSST). Serum 25(OH) D levels were measured by radioimmunoassay. Additional assessments included measurement of physical activity, functional performance and mood/depression. Associations between cognitive function and 25(OH) D levels were explored using locally weighted and linear regression models. Results: In total, 3,133 men (mean (+/- SD) age 60 +/- 11 years) were included in the analysis. The mean (+/- SD) 25(OH) D concentration was 63 +/- 31 nmol/l. In age-adjusted linear regressions, high levels of 25(OH) D were associated with high scores on the copy component of the ROCF test (beta per 10 nmol/l = 0.096; 95% CI 0.049 to 0.144), the CTRM test (beta per 10 nmol/l= 0.075; 95% CI 0.026 to 0.124) and the DSST (beta per 10 nmol/l = 0.318; 95% CI 0.235 to 0.401). After adjusting for additional confounders, 25(OH) D levels were associated with only score on the DSST (beta per 10 nmol/l = 0.152; 95% CI 0.051 to 0.253). Locally weighted and spline regressions suggested the relationship between 25(OH) D concentration and cognitive function was most pronounced at 25(OH) D concentrations below 35 nmol/l. Conclusion: In this study, lower 25(OH) D levels were associated with poorer performance on the DSST. Further research is warranted to determine whether vitamin D sufficiency might have a role in preserving cognitive function in older adults.
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| 17. |
- Lee, David M., et al.
(författare)
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The association between different cognitive domains and age in a multi-centre study of middle-aged and older European men
- 2009
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Ingår i: International Journal of Geriatric Psychiatry. - : Wiley. - 1099-1166 .- 0885-6230. ; 24:11, s. 1257-1266
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Tidskriftsartikel (refereegranskat)abstract
- Objectives We determined levels of cognitive functioning in community dwelling men aged 40-79 (n = 3265) from eight European centres and investigated to what extent cognitive performance varied between centres, the association between different cognitive domains and age, educational level, co-morbidity and lifestyle factors and the respective contributions of centre and individual factors to cognitive performance. Methods Cognitive domains assessed were visuo-constructional ability and Visual memory (Rey-Osterrieth Complex Figure test, ROCF), topographical memory (Camden Topographical Recognition Memory test, CTRM) and processing speed (Digit-Symbol Substitution test, DSST). Results There were significant between-centre differences in all four cognitive test scores. Using multilevel linear regression analysis (MLRA), age, education, depression, physical performance and smoking were independent predictors of cognitive function and these variables explained 10-13% of the variation in cognitive scores between centres and 17-36% of the variation in scores between individuals within centres. Conclusion Our data suggest that although a proportion of the variance in cognitive function among European men is explained by individual level differences, a significant proportion is due to contextual phenomenon. Such contextual factors need to be considered when analysing multi-centre data and European men should not be treated as homogeneous when assessing cognitive performance using existing instruments. Copyright (C) 2009 John Wiley & Sons, Ltd.
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| 18. |
- Lee, David M., et al.
(författare)
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The European Male Ageing Study (EMAS): design, methods and recruitment
- 2009
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Ingår i: International Journal of Andrology. - : Wiley. - 0105-6263 .- 1365-2605. ; 32:1, s. 11-24
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Tidskriftsartikel (refereegranskat)abstract
- Life expectancy is increasing in most developed countries, in part due to improved socioeconomic conditions and in part to advances in healthcare. It is widely acknowledged that the promotion of healthy ageing by delaying, minimizing or preventing disabilities or diseases is one of the most important public health objectives in this century. In contrast to the menopausal transition in females, we know relatively little about the contribution of androgens and anabolic hormones to the quality of ageing in men. The European Male Ageing Study (EMAS) is a multicentre prospective cohort designed to examine the prevalence, incidence and geographical distribution of gender-specific and general symptoms of ageing in men, including their endocrine, genetic and psychosocial predictors. Men aged 40-79 years were recruited from eight European centres: Florence (Italy), Leuven (Belgium), Lodz (Poland), Malmo (Sweden), Manchester (UK), Santiago de Compostela (Spain), Szeged (Hungary) and Tartu (Estonia). Subjects were recruited from population registers and those who agreed to take part completed a detailed questionnaire including aspects of personal and medical history, lifestyle factors and sexual function. Objective measures of body size, cognition, vision, skeletal health and neuromuscular function were obtained. Blood and DNA specimens were collected for a range of biochemical and genetic analyses. After an average of 4 years, it is planned to resurvey the participants with similar assessments. A total of 3369 men with a mean age of 60 +/- 11 years were recruited. The mean centre response rate was 43%, and highest in those aged 50-59 years. Those who participated were marginally younger than those who were invited but declined to participate (60.0 vs. 61.1 years). Participants left education slightly later than a sample of non-participants, though there were no consistent differences in levels of general health, physical activity, or smoking. EMAS will provide new population-based data concerning the main features that characterize ageing in men and its critical determinants, particularly with reference to age-related changes in hormone levels. Such information is an important prerequisite to develop effective strategies to reduce age-related disabilities and optimise health and well-being into old-age.
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| 19. |
- Lee, David M., et al.
(författare)
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Vitamin D, parathyroid hormone and the metabolic syndrome in middle-aged and older European men
- 2009
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 161:6, s. 947-954
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Low serum 25-hydroxyviatmin D (25(OH)D) and elevated parathyroid hormone (PTH) levels have been linked to insulin resistance, the metabolic syndrome (MetS) and its components. Data in healthy, community-dwelling Europeans are lacking, and previous studies have not excluded subjects receiving drug treatments that may distort the relationship between 25(OH)D/PTH and MetS. The aim of our analysis was to examine the association of 25(OH)D and PTH with Adult Treatment Panel III-defined MetS in middle-aged and older European men Design: This was a population-based, cross-sectional study of 3369 men aged 40-79 years enrolled in the European Male Ageing Study. Results After exclusion of subjects with missing data. 3069 men with a mean (+/- S.D.) age of 60 +/- 11 years were included in the analysis. Age-adjusted 25(OH)D levels were inversely associated with waist circumference, systolic blood pressure (BP), triglycerides, and glucose (all P < 0.01) Age-adjusted PTH levels were only associated with waist and diastolic BP (both P < 0.05). After adjusting for age, centre, season and lifestyle factors the odds for MetS decreased across increasing 25(OH)D quintiles (odds ratios 0.48 (95% confidence intervals 0.36-0.64) highest versus lowest quintile. P-trend < 0.001). This relationship was unchanged after adjustment for PTH, but was attenuated after additional adjustment for homeostasis model assessment of insulin resistance (0.60 (0.47-0.78) P-trend < 0.001) There was no association between PTH and MetS. Conclusions: Our results demonstrate an inverse relationship between 25(OH)D levels and MetS, which is independent of several confounders and PTH. The relationship is partly explained by insulin resistance. The clinical significance of these observations warrants further study
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| 20. |
- O'Connor, Daryl B, et al.
(författare)
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Assessment of sexual health in aging men in Europe: Development and validation of the European Male Ageing Study sexual function questionnaire
- 2008
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Ingår i: Journal of Sexual Medicine. - : Oxford University Press (OUP). - 1743-6109 .- 1743-6095. ; 5:6, s. 1374-1385
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Tidskriftsartikel (refereegranskat)abstract
- Introduction. Assessment of male sexual dysfunction has been the focus of substantial scientific effort. Less research has focused on the development of instruments for the measurement of sexual functioning in aging men. Aim. The aims of this study were: (i) to characterize the psychometric properties of a new brief, reliable, and valid measure of male sexual functioning for use in a large population survey of middle-aged and elderly European men; and (ii) specifically, to determine whether the new instrument, the European Male Ageing Study-sexual function questionnaire (EMAS-SFQ), discriminates between men with high and low levels of circulating testosterone (T) (total T, free T, and bioavailable T). Method. One thousand six hundred men aged 40-79 years completed the self-administered EMAS-SFQ, the Beck depression inventory, and provided a blood sample for assessment of sex hormones. Eighty-five men aged 35-74 years completed the EMAS-SFQ twice, 2 weeks apart to examine the test-retest reliability of the instrument. Main Outcome Measures. Scores on the EMAS-SFQ in relation to age and T levels. Results. Principal component analysis showed that the EMAS-SFQ had four distinct domains (overall sexual functioning [OSF], masturbation, sexual functioning-related distress, and change in sexual functioning). The instrument demonstrated excellent internal and test-retest reliability, as well as convergent, divergent, and discriminant validity. Men with the lowest levels of total, free, and bioavailable T reported lower OSF scores compared to men with the highest T levels. Conclusion. The EMAS-SFQ is a valid and reproducible instrument, sensitive to age and T levels. It should be suitable for the assessment of sexual health in population samples of men in epidemiological studies of aging.
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| 21. |
- O'Neill, A., et al.
(författare)
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Reduced self-heating by strained silicon substrate engineering
- 2008
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 254:19, s. 6182-6185
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Tidskriftsartikel (refereegranskat)abstract
- Substrate engineering innovations such as SOI and the use of Si/SiGe virtual substrates become necessary in order to maintain performance leverage of integrated circuits with continued scaling. The relevance of thermal effects in device design increases since the thermal conductivity of these new materials is poor. The electrical performance of devices fabricated on thin virtual substrates grown by two different techniques is presented. It is found that self-heating is reduced and that thermal resistance measurements agree with modelling predictions. The reduction in performance enhancement seen in many strained Si MOSFETs is found here to be largely due to self-heating effects, rather than parasitics or the loss of strain.
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| 22. |
- Persson, S., et al.
(författare)
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Fabrication and characterisation of strained Si heterojunction bipolar transistors on virtual substrates
- 2008
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Ingår i: IEEE INTERNATIONAL ELECTRON DEVICES MEETING 2008, TECHNICAL DIGEST. - NEW YORK : IEEE. ; , s. 735-738
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Konferensbidrag (refereegranskat)abstract
- Strained Si HBTs have been demonstrated for the first time with a maximum current gain (P) of 3700 using a relaxed Si(0.85)Ge(0.15) virtual substrate, Si(0.7)Ge(0.3) base and strained Si emitter. This represents 10x and 27x larger gain compared with pseudomorphic SiGe HBTs and Si control BJTs which were manufactured in parallel and had current gains of 334 and 135, respectively. The strained Si HBTs exhibited satisfactory breakdown voltage (2.5 V) compared with SiGe HBTs (2.7 V) and Si BJTs (4.5 V) and excellent control of collector off-state leakage (< 20 fA).
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| 24. |
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| 25. |
- Sprigg, N., et al.
(författare)
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Early Recovery and Functional Outcome are Related with Causal Stroke Subtype : Data from the Tinzaparin in Acute Ischemic Stroke Trial
- 2007
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Ingår i: Journal of Stroke & Cerebrovascular Diseases. - : Elsevier BV. - 1052-3057 .- 1532-8511. ; 16:4, s. 180-184
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Baseline severity and causal subtype are predictors of outcome in ischemic stroke. We used data from the Tinzaparin in Acute Ischemic Stroke Trial (TAIST) to further assess the relationship among stroke subtype, early recovery, and outcome. Methods: Patients with ischemic stroke (<48 hours ictus) and enrolled into TAIST were included. Severity was measured prospectively as the Scandinavian Neurological Stroke Scale (SNSS) at days 0, 4, 7, and 10. Causal subtype as large artery atherosclerosis (LAA), cardioembolism (CE), or small vessel occlusion (SVO) was assigned after standard investigations. The rate of recovery was calculated as the change in SNSS at each time point. Functional outcome was assessed using the modified Rankin Scale (mRS) and Barthel Index at day 90. Results: Analyses were performed on the 1190 patients in TAIST who met criteria for LAA, CE, and SVO. The largest change in SNSS score occurred between baseline and day 4 and was greatest in SVO (median improvement 4 U), compared with LAA (median improvement 2 U) and CE (median improvement 2 U) (P < .0001). If no improvement in SNSS had occurred by day 4, irrespective of subgroup, then early recovery (median SNSS improvement by day 10: 2) and functional outcome (mRS 4) tended to be limited, patients who recovered early tended to continue to improve (median SNSS improvement by day 10: 11) and had a better outcome at day 90 (median, mRS 2). Conclusions: Recovery is related to causal subtype. In all subtypes most recovery occurred by day 4, and was predictive of longer-term functional outcome. © 2007 National Stroke Association.
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| 26. |
- Sprigg, N., et al.
(författare)
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Stroke severity, early recovery and outcome are each related with clinical classification of stroke : Data from the 'Tinzaparin in Acute Ischaemic Stroke Trial' (TAIST)
- 2007
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Ingår i: Journal of the Neurological Sciences. - : Elsevier BV. - 0022-510X .- 1878-5883. ; 254:1-2, s. 54-59
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Baseline severity and clinical stroke syndrome (Oxford Community Stroke Project, OCSP) classification are predictors of outcome in stroke. We used data from the 'Tinzaparin in Acute Ischaemic Stroke Trial' (TAIST) to assess the relationship between stroke severity, early recovery, outcome and OCSP syndrome. Methods: TAIST was a randomised controlled trial assessing the safety and efficacy of tinzaparin versus aspirin in 1484 patients with acute ischaemic stroke. Severity was measured as the Scandinavian Neurological Stroke Scale (SNSS) at baseline and days 4, 7 and 10, and baseline OCSP clinical classification recorded: total anterior circulation infarct (TACI), partial anterior circulation infarct (PACI), lacunar infarct (LACI) and posterior circulation infarction (POCI). Recovery was calculated as change in SNSS from baseline at day 4 and 10. The relationship between stroke syndrome and SNSS at days 4 and 10, and outcome (modified Rankin Scale at 90 days) were assessed. Results: Stroke severity was significantly different between TACI (most severe) and LACI (mildest) at all four time points (p < 0.001), with no difference between PACI and POCI. The largest change in SNSS score occurred between baseline and day 4, improvement was least in TACI (median 2 units), compared to other groups (median 3 units) (p < 0.001). If SNSS did not improve by day 4, then early recovery and late functional outcome tended to be limited irrespective of clinical syndrome (SNSS, baseline: 31, day 10: 32, mRS, day 90: 4), patients who recovered early tended to continue to improve and had better functional outcome irrespective of syndrome (SNSS, baseline: 35, day 10: 50, mRS, day 90: 2). Conclusions: Although functional outcome is related to baseline clinical syndrome (best with LACI, worst with TACI), patients who improve early have a more favourable functional outcome, irrespective of their OCSP syndrome. Hence, patients with a TACI syndrome may still achieve a reasonable outcome if early recovery occurs. © 2007 Elsevier B.V. All rights reserved.
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