| 1. |
- Abreu, P., et al.
(författare)
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Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets
- 2000
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 13:4, s. 573-589
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Tidskriftsartikel (refereegranskat)abstract
- The fragmentation functions of quarks and gluons are measured in various three-jet topologies in Z decays from the full data set collected with the DELPHI detector at the Z resonance between 1992 and 995. The results at different values of transverse momentum-like scales are compared. A parameterization of the quark and gluon fragmentation functions at a fixed reference scale is given. The quark and gluon fragmentation functions show the predicted pattern of scaling violations. The scaling violation for quark jets as a function of a transverse momentum-like scale is in a good agreement with that observed in lower energy e+e- annihilation experiments. For gluon jets it appears to be significantly stronger. The scale dependences of the gluon and quark fragmentation functions agree with the prediction of the DGLAP evolution equations from which the colour factor ratio CA/CF is measured to be: CA/CF = 2.26 ± 0.09stat. ± 0.06sys. ± 0.12clus.,scale..
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| 2. |
- Abreu, P., et al.
(författare)
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Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
- 2001
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
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Tidskriftsartikel (refereegranskat)abstract
- Muon pair production in the process e+e- → e+e- μ+μ- is studied using the data taken at LEP1 (√s ≃ mz) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb-1. The QED predictions have been tested over the whole Q2 range accessible at LEP1 (from several GeV2/c4 to several hundred GeV2/c4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function Fγ 2. Azimuthal correlations are used to obtain information on additional structure functions, Fγ A and Fγ B, which originate from interference terms of the scattering amplitudes. The measured ratios Fγ A/Fγ 2 and FγB/Fγ 2 are significantly different from zero and consistent with QED predictions.
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| 3. |
- Abreu, P., et al.
(författare)
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Search for sleptons in e+e- collisions at √s = 183 to 189 GeV
- 2001
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 29-42
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Tidskriftsartikel (refereegranskat)abstract
- Data taken by the DELPHI experiment at centre-of-mass energies of 183 GeV and 189 GeV with a total integrated luminosity of 212 pb-1 have been used to search for the supersymmetric partners of the electrons, muons, and taus in the context of the Minimal Supersymmetric Standard Model (MSSM). The decay topologies searched for were the direct decay (ℓ̃ → ℓx̃), producing acoplanar lepton pairs plus missing energy, and the cascade decay (ℓ → ℓx̃0 2 → ℓγx̃0 1), producing acoplanar lepton and photon pairs plus missing energy. The observed number of events is in agreement with Standard Model predictions. The 95% CL excluded mass limits for selectrons, smuons and staus are mẽ ≤ 87 GeV/c2, mμ̃ ≤ 80 GeV/c2 and mτ̃ 75 GeV/c2, respectively, for values of μ=-200 GeV/c2 and tanβ=1.5.
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| 4. |
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| 5. |
- Hillier, Ladeana W, et al.
(författare)
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Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution
- 2004
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 432:7018, s. 695-716
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Tidskriftsartikel (refereegranskat)abstract
- We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.
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| 6. |
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| 7. |
- Littleton, JM, et al.
(författare)
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Challenges to medications development in treating alcohol dependence: An international perspective - Summary of a symposium held at the ESBRA Congress, Prague, 13 September 2003
- 2004
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Ingår i: Alcohol and Alcoholism. - : Oxford University Press (OUP). - 1464-3502. ; 39:4, s. 271-275
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Tidskriftsartikel (refereegranskat)abstract
- Few medications for treating alcohol dependence exist. Greater partnership is needed between academia and the pharmaceutical industry to develop, licence and market efficacious medications for treating alcohol dependence. Methodologies that span the divide between preclinical and large-scale clinical studies need to be developed in order to provide sufficient information on safety, toleration, drug-interaction profile and efficacy, with which to guide development decisions. Due to the heterogeneous nature of alcohol dependence, the effort of developing an efficacious medication is likely to be enhanced by clearer choices about the characteristics of the population. Careful consideration of potential mechanism of action of the putative therapeutic medication should enable the appropriate choice of drinking endpoint. The pharmaceutical industry in collaboration with academia might need to develop new approaches to determining appropriate treatment endpoints with regulatory bodies. The investment risk to industry should be appraised not only in terms of the rather poor results of previous marketing efforts but with a view to the opportunity to penetrate a potentially enormous and largely untapped market.
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| 8. |
- Parker, P, et al.
(författare)
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Progress in integrated assessment and modelling
- 2002
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Ingår i: Environmental Modelling & Software. - 1364-8152. ; 17:3, s. 209-217
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Tidskriftsartikel (refereegranskat)abstract
- Environmental processes have been modelled for decades. However. the need for integrated assessment and modeling (IAM) has,town as the extent and severity of environmental problems in the 21st Century worsens. The scale of IAM is not restricted to the global level as in climate change models, but includes local and regional models of environmental problems. This paper discusses various definitions of IAM and identifies five different types of integration that Lire needed for the effective solution of environmental problems. The future is then depicted in the form of two brief scenarios: one optimistic and one pessimistic. The current state of IAM is then briefly reviewed. The issues of complexity and validation in IAM are recognised as more complex than in traditional disciplinary approaches. Communication is identified as a central issue both internally among team members and externally with decision-makers. stakeholders and other scientists. Finally it is concluded that the process of integrated assessment and modelling is considered as important as the product for any particular project. By learning to work together and recognise the contribution of all team members and participants, it is believed that we will have a strong scientific and social basis to address the environmental problems of the 21st Century.
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| 9. |
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| 10. |
- Bragdon, Charles R, 1959, et al.
(författare)
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Comparison of two digital radiostereometric analysis methods in the determination of femoral head penetration in a total hip replacement phantom
- 2004
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Ingår i: J Orthop Res. - : Wiley. - 0736-0266. ; 22:3, s. 659-64
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Tidskriftsartikel (refereegranskat)abstract
- Radiostereometric analysis (RSA) has been used extensively to evaluate the magnitude and direction of penetration of the femoral head into the acetabular component of a total hip replacement as a result of polyethylene wear and creep. The accuracy and precision of an RSA study depends on several factors, including the radiographic technique, the analytical software, and the positioning of the tantalum markers. This study had three sequential purposes. First, an in vitro phantom model was used to quantify the accuracy and precision of digital images versus conventional radiography in RSA measurements of penetration of the femoral head into the acetabular shell in a total hip replacement. The Umea RSA software package was used for analysis of both the conventional films, which were digitized at a resolution of 300 DPI, and digital radiographs, which were converted from a DICOM format at a resolution of 218 DPI. Digital radiography was found to be superior. Next, two methods of RSA analysis currently in use for determining femoral head penetration into polyethylene of total joint replacements were compared. Using the phantom model, we compared the Umea RSA system (Biomedical Innovations AB) to the RSA-CMS (RSA Clinical Measurement Solution) and in both cases used the digital radiographs. The Umea RSA system was found to be superior. Finally, two methods of marking the position of the acetabular component with tantalum beads were compared: one in which beads were inserted into previously described towers protruding from the back of the acetabular shell and another in which beads were placed into the peripheral flange of the polyethylene liner using the Umea RSA analysis system of the digital radiographs. The results using the two marker configurations were similar.
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| 11. |
- Bragdon, C. R., et al.
(författare)
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Experimental assessment of precision and accuracy of radio stereometric analysis for the determination of polyethylene wear in a total hip replacement model
- 2002
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Ingår i: Journal of Orthopaedic Research. ; 20:4, s. 688-695
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to develop and testa phantom model based on actual total hip replacement (THR) components to simulate the true penetration of the femoral h cad resulting fro in polyethylene car, This Model was used to Study both the accuracy and the precision of radiostereometric analysis, RSA, in measuring wear. We also used this model to evaluate optimum tantalum bead configuration for this particular cup design when used in a clinical setting. A physical model of a total hip replacement (a phantom) was constructed which Could simulate progressive. three-dimensional (3-D) penetration of the femoral head into the polyethylene component of a THR. Using it coordinate Measuring machine (CMM) the positioning of the femoral head using the phantom was measured to be accurate to within 7 mum The accuracy and precision of an RSA analysis system was determined from five repeat examinations of the phantom using various experimental set-ups of the phantom. The accuracy of the radiostereometric analysis, in this optimal experimental set-up studied was 33 mum for the medial direction, 22 mum for the superior direction, 86 mum for the posterior direction and 55 mum for the resultant 3-D vector length. The corresponding precision at the 95% confidence interval of the test results for repositioning the phantom five times. measured 8.4 mum for the medial direction, 5.5 mum for the superior direction. 16.0 mum for the posterior direction. and 13 5 mum for the resultant 3-D vector length. This in vitro model is proposed as a useful tool for developing a standard for the evaluation of radiostereometric and other radiographic methods used to measure in vivo wear. (C) 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd, All rights reserved.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Ioppolo, J. L., et al.
(författare)
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Kinematic joint measurement RSA flouroscopy
- 2004
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Ingår i: Proc. Ann. Meet. Aust. Coll. Phys. Scient. Eng. Med. (WA Branch). ; , s. 7-7
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Andersson, U, et al.
(författare)
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High mobility group 1 protein (HMG-1) stimulates proinflammatory cytokine synthesis in human monocytes
- 2000
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 0022-1007 .- 1540-9538. ; 192:4, s. 565-570
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Tidskriftsartikel (refereegranskat)abstract
- Lipopolysaccharide (LPS) is lethal to animals because it activates cytokine release, causing septic shock and tissue injury. Early proinflammatory cytokines (e.g., tumor necrosis factor [TNF] and interleukin [IL]-1) released within the first few hours of endotoxemia stimulate mediator cascades that persist for days and can lead to death. High mobility group 1 protein (HMG-1), a ubiquitous DNA-binding protein, was recently identified as a “late” mediator of endotoxin lethality. Anti–HMG-1 antibodies neutralized the delayed increase in serum HMG-1, and protected against endotoxin lethality, even when passive immunization was delayed until after the early cytokine response. Here we examined whether HMG-1 might stimulate cytokine synthesis in human peripheral blood mononuclear cell cultures. Addition of purified recombinant HMG-1 to human monocyte cultures significantly stimulated the release of TNF, IL-1α, IL-1β, IL-1RA, IL-6, IL-8, macrophage inflammatory protein (MIP)-1α, and MIP-1β; but not IL-10 or IL-12. HMG-1 concentrations that activated monocytes were within the pathological range previously observed in endotoxemic animals, and in serum obtained from septic patients. HMG-1 failed to stimulate cytokine release in lymphocytes, indicating that cellular stimulation was specific. Cytokine release after HMG-1 stimulation was delayed and biphasic compared with LPS stimulation. Computer-assisted image analysis demonstrated that peak intensity of HMG-1–induced cellular TNF staining was comparable to that observed after maximal stimulation with LPS. Administration of HMG-1 to Balb/c mice significantly increased serum TNF levels in vivo. Together, these results indicate that, like other cytokine mediators of endotoxin lethality (e.g., TNF and IL-1), extracellular HMG-1 is a regulator of monocyte proinflammatory cytokine synthesis.
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| 20. |
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| 21. |
- Becker, D., et al.
(författare)
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Engineering of a glycosidase Family 7 cellobiohydrolase to more alkaline pH optimum : the pH behaviour of Trichoderma reesei CeI7A and its E223S/A224H/L225V/T226A/D262G mutant
- 2001
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Ingår i: Biochemical Journal. - 0264-6021 .- 1470-8728. ; 356, s. 19-30
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structures of Family 7 glycohydrolases suggest that a histidine residue near the acid/base catalyst could account for the higher pH optimum of the Humicola insolens endoglucanase Cel7B, than the corresponding Trichoderma reesei enzymes. Modelling studies indicated that introduction of histidine at the homologous position in T. reesei Cel7A (Ala(224)) required additional changes to accommodate the bulkier histidine side chain. X-ray crystallography of the catalytic domain of the E223S/A224H/L225V/T226A/D262G mutant reveals that major differences from the wild-type are confined to the mutations themselves, The introduced histidine residue is in plane with its counterpart in H. insolens Cel7B, but is 1.0 Angstrom (= 0.1 nm) closer to the acid/base Glu(217) residue, with a 3.1 Angstrom contact between N-2 and O'(1). The pH variation of k(cat)/K-m for 3,4-dinitrophenyl lactoside hydrolysis was accurately bell-shaped for both wildtype and mutant, with pK(1) shifting from 2.22+/-0.03 in the wild-type to 3.19+/-0.03 in the mutant, and pK(2) shifting from 5.99+/-0.02 to 6.78+/-0.02. With this poor substrate, the ionizations probably represent those of the free enzyme. The relative k(cat) for 2-chloro-4-nitrophenyl lactoside showed similar behaviour. The shift in the mutant pH optimum was associated with lower k(cat)/K-m values for both lactosides and cellobiosides, and a marginally lower stability. However, k(cat) values for cellobiosides are higher for the mutant. This we attribute to reduced nonproductive binding in the +1 and +2 subsites; inhibition by cellobiose is certainly relieved in the mutant. The weaker binding of cellobiose is due to the loss of two water-mediated hydrogen bonds.
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| 22. |
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| 23. |
- Bonnet, D., et al.
(författare)
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Calanus the cannibal
- 2004
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Ingår i: Journal of Plankton Research. - 0142-7873. ; 26:8, s. 937-948
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Tidskriftsartikel (refereegranskat)abstract
- Recent modelling efforts have suggested that cannibalism on eggs and young nauplii is an important factor controlling the population dynamics of Calanus. We measured cannibalistic feeding rates on eggs and nauplii of Calanus helgolandicus in the laboratory. Clearance rates on nauplii were similar to102 mL ind.(-1) day(-1), while generally higher on eggs (320 mL ind.(-1) day(-1)). Female starvation did not affect ingestion rates of eggs. We discuss our results in light of published model predictions, cannibalistic feeding rates of other copepods, and field distributions of Calanus developmental stages.
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| 24. |
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| 25. |
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| 26. |
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| 27. |
- Devereux, R. B., et al.
(författare)
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Prognostic significance of left ventricular mass change during treatment of hypertension
- 2004
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Ingår i: Jama. - 1538-3598. ; 292:19, s. 2350-6
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Increased baseline left ventricular (LV) mass predicts cardiovascular (CV) complications of hypertension, but the relation between lower LV mass and outcome during treatment for hypertension is uncertain. OBJECTIVE: To determine whether reduction of LV mass during antihypertensive treatment modifies risk of major CV events independent of blood pressure change. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort substudy of the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) randomized clinical trial, conducted from 1995 to 2001. A total of 941 prospectively identified patients aged 55 to 80 years with essential hypertension and electrocardiographic LV hypertrophy had LV mass measured by echocardiography at enrollment in the LIFE trial and thereafter were followed up annually for a mean (SD) of 4.8 (1.0) years for CV events. MAIN OUTCOME MEASURES: Composite end point of CV death, fatal or nonfatal myocardial infarction, and fatal or nonfatal stroke. RESULTS: The composite end point occurred in 104 patients (11%). The multivariable Cox regression model showed a strong association between lower in-treatment LV mass index and reduced rate of the composite CV end point (hazard ratio [HR], 0.78 per 1-SD (25.3) decrease in LV mass index; 95% confidence interval [CI], 0.65-0.94; P = .009) over and above that predicted by reduction in blood pressure. There were parallel associations between lower in-treatment LV mass index and lower CV mortality (HR, 0.62; 95% CI, 0.47-0.82; P = .001), stroke (HR, 0.76; 95% CI, 0.60-0.96; P = .02), myocardial infarction (HR, 0.85; 95% CI, 0.62-1.17, P = .33), and all-cause mortality (HR, 0.72; 95% CI, 0.59-0.88, P = .002), independent of systolic blood pressure and assigned treatment. Results were confirmed in analyses adjusting for additional CV risk factors, electrocardiographic changes, or when only considering events after the first year of study treatment. CONCLUSION: In patients with essential hypertension and baseline electrocardiographic LV hypertrophy, lower LV mass during antihypertensive treatment is associated with lower rates of clinical end points, additional to effects of blood pressure lowering and treatment modality.
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| 28. |
- Devereux, R. B., et al.
(författare)
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Regression of hypertensive left ventricular hypertrophy by losartan compared with atenolol: the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) trial
- 2004
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Ingår i: Circulation. - 1524-4539. ; 110:11, s. 1456-62
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: An echocardiographic substudy of the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) trial was designed to test the ability of losartan to reduce left ventricular (LV) mass more than atenolol. METHODS AND RESULTS: A total of 960 patients with essential hypertension and LV hypertrophy (LVH) on screening ECG were enrolled at centers in 7 countries and studied by echocardiography at baseline and after 1, 2, 3, 4, and 5 years' randomized therapy. Clinical examination and blinded readings of echocardiograms in 457 losartan-treated and 459 atenolol-treated participants with > or =1 follow-up measurement of LV mass index (LVMI) were used in an intention-to-treat analysis. Losartan-based therapy induced greater reduction in LVMI from baseline to the last available study than atenolol with adjustment for baseline LVMI and blood pressure and in-treatment pressure (-21.7+/-21.8 versus -17.7+/-19.6 g/m2; P=0.021). Greater LVMI reduction with losartan was observed in women and men, participants >65 or <65 years of age, and with mild or more severe baseline hypertrophy. The difference between treatment arms in LVH regression was due mainly to reduced concentricity of LV geometry in both groups and lesser increase in LV internal diameter in losartan-treated patients. CONCLUSIONS: Antihypertensive treatment with losartan, plus hydrochlorothiazide and other medications when needed for pressure control, resulted in greater LVH regression in patients with ECG LVH than conventional atenolol-based treatment. Thus, angiotensin receptor antagonism by losartan has superior efficacy for reversing LVH, a cardinal manifestation of hypertensive target organ damage.
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| 29. |
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| 30. |
- Irigoien, X., et al.
(författare)
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Feeding of Calanus finmarchicus nauplii in the Irminger Sea
- 2003
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Ingår i: Marine Ecology-Progress Series. - 0171-8630. ; 262, s. 193-200
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies have shown that the passage from nauplius to copepodite is a key event in the population dynamics of Calan us finmarchicus. As a first step towards understanding if and how trophic interactions influence this event, we investigated the feeding of C. finmarchicus nauplii IV-VI in the Irminger Sea during spring and summer in a series of incubation experiments. Generally, feeding efficiencies were highest on large cells, whereas small flagellates were ingested at very low rates. Colonies of Phaeocystis sp. were not ingested. Among the larger cells, the diatoms Chaetoceros pelagicus and Tropodineis sp. and the ciliate Strombidium sp. were the main food sources. We observed a negative relationship between the percentage of diatoms in the food environment and the filtration rate on Strombidium sp. We therefore suggest that the combination of low feeding efficiency on small cells and the generally low concentrations of ciliates in oceanic waters explains why C, finmarchicus relies on phytoplankton blooms for recruitment from nauplius to the first copepodite stage.
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| 31. |
- Julius, S., et al.
(författare)
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Cardiovascular risk reduction in hypertensive black patients with left ventricular hypertrophy: the LIFE study
- 2004
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Ingår i: J Am Coll Cardiol. - 0735-1097. ; 43:6, s. 1047-55
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: We report on a subanalysis of the effects of losartan and atenolol on cardiovascular events in black patients in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) study. BACKGROUND: The LIFE study compared losartan-based to atenolol-based therapy in 9,193 hypertensive patients with left ventricular hypertrophy (LVH). Overall, the risk of the primary composite end point (cardiovascular death, stroke, myocardial infarction) was reduced by 13% (p = 0.021) with losartan, with similar blood pressure (BP) reduction in both treatment groups. There was a suggestion of interaction between ethnic background and treatment (p = 0.057). METHODS: Exploratory analyses were performed that placed LIFE study patients into black (n = 533) and non-black (n = 8,660) categories, overall, and in the U.S. (African American [n = 523]; non-black [n = 1,184]). RESULTS: A significant interaction existed between the dichotomized groups (black/non-black) and treatment (p = 0.005); a test for qualitative interaction was also significant (p = 0.016). The hazard ratio (losartan relative to atenolol) for the primary end point favored atenolol in black patients (1.666 [95% confidence interval (CI) 1.043 to 2.661]; p = 0.033) and favored losartan in non-blacks (0.829 [95% CI 0.733 to 0.938]; p = 0.003). In black patients, BP reduction was similar in both groups, and regression of electrocardiographic-LVH was greater with losartan. CONCLUSIONS: Results of the subanalysis are sufficient to generate the hypothesis that black patients with hypertension and LVH might not respond as favorably to losartan-based treatment as non-black patients with respect to cardiovascular outcomes, and do not support a recommendation for losartan as a first-line treatment for this purpose. The subanalysis is limited by the relatively small number of events.
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| 32. |
- Kleywegt, Gerard J, et al.
(författare)
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The Uppsala Electron-Density Server
- 2004
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Ingår i: Acta Crystallographica Section D. - 0907-4449 .- 1399-0047. ; 60:Pt 12 Pt 1, s. 2240-2249
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Tidskriftsartikel (refereegranskat)abstract
- The Uppsala Electron Density Server (EDS; http://eds.bmc.uu.se/) is a web-based facility that provides access to electron-density maps and statistics concerning the fit of crystal structures and their maps. Maps are available for approximately 87% of the crystallographic Protein Data Bank (PDB) entries for which structure factors have been deposited and for which straightforward map calculations succeed in reproducing the published R value to within five percentage points. Here, an account is provided of the methods that are used to generate the information contained in the server. Some of the problems that are encountered in the map-generation process as well as some spin-offs of the project are also discussed.
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| 33. |
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| 34. |
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| 35. |
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| 36. |
- Lloyd-Spets, Anita, et al.
(författare)
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SiC based field effect gas sensors for industrial applications
- 2001
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Ingår i: Physica status solidi. A, Applied research. - 0031-8965 .- 1521-396X. ; 185:1, s. 15-25
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Tidskriftsartikel (refereegranskat)abstract
- The development and field-testing of high-temperature sensors based on silicon carbide devices have shown promising results in several application areas. Silicon carbide based field-effect sensors can be operated over a large temperature range, 100-600 degreesC, and since silicon carbide is a chemically very inert material these sensors can be used in environments like exhaust gases and flue gases from boilers. The sensors respond to reducing gases like hydrogen, hydrocarbons and carbon monoxide. The use of different temperatures, different catalytic metals and different structures of the gate metal gives selectivity to different gases and arrays of sensors can be used to identify and monitor several components in gas mixtures. MOSFET sensors based on SIC combine the advantage of simple circuitry with a thicker insulator, which increases the long term stability of the devices. In this paper we describe silicon carbide MOSFET sensors and their performance and give: examples of industrial applications such as monitoring of car exhausts and flue gases. Chemometric methods have been used for the evaluation of the data.
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| 37. |
- Okin, P. M., et al.
(författare)
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Regression of electrocardiographic left ventricular hypertrophy during antihypertensive treatment and the prediction of major cardiovascular events
- 2004
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Ingår i: Jama. - 1538-3598. ; 292:19, s. 2343-9
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Tidskriftsartikel (refereegranskat)abstract
- CONTEXT: Electrocardiographic left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular (CV) morbidity and mortality. However, the predictive value of changes in the magnitude of electrocardiographic LVH criteria during antihypertensive therapy remains unclear. OBJECTIVE: To test the hypothesis that lesser severity of electrocardiographic LVH during antihypertensive treatment is associated with decreased CV morbidity and mortality, independent of blood pressure levels and reduction and treatment modality. DESIGN, SETTING, AND PARTICIPANTS: Double-blind, randomized, parallel-group study conducted in 1995-2001 among 9193 men and women with hypertension aged 55 through 80 years (mean, 67 years), with electrocardiographic LVH by Cornell voltage-duration product or Sokolow-Lyon voltage criteria and enrolled in the Losartan Intervention For Endpoint Reduction in Hypertension (LIFE) study. INTERVENTIONS: Losartan- or atenolol-based treatment regimens, with follow-up assessments for at least 4 (mean, 4.8 [SD, 0.9]) years. MAIN OUTCOME MEASURE: Composite end point of CV death, myocardial infarction (MI), or stroke in relation to severity of electrocardiographic LVH determined at baseline and on subsequent electrocardiograms obtained at 1 or more annual revisits. RESULTS: Cardiovascular death, nonfatal MI, or stroke occurred in 1096 patients (11.9%). In Cox regression models controlling for treatment type, baseline Framingham risk score, baseline and in-treatment blood pressure, and severity of baseline electrocardiographic LVH by Cornell product and Sokolow-Lyon voltage, less-severe in-treatment LVH by Cornell product and Sokolow-Lyon voltage were associated with 14% and 17% lower rates, respectively, of the composite CV end point (adjusted hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.82-0.90; P<.001 for every 1050-mm x ms [1-SD] decrease in Cornell product; and HR, 0.83; 95% CI, 0.78-0.88; P<.001 for every 10.5-mm [1-SD] decrease in Sokolow-Lyon voltage). In parallel analyses, lower Cornell product and Sokolow-Lyon voltage were each independently associated with lower risks of CV mortality (HR, 0.78; 95% CI, 0.73-0.83; P<.001; and HR, 0.80; 95% CI, 0.73-0.87; P<.001, respectively), MI (HR, 0.90; 95% CI, 0.82-0.98; P=.01; and HR, 0.90; 95% CI, 0.81-1.00; P = .04), and stroke (HR, 0.90; 95% CI, 0.84-0.96; P=.002; and HR, 0.81; 95% CI, 0.75-0.89; P<.001). CONCLUSIONS: Less-severe electrocardiographic LVH by Cornell product and Sokolow-Lyon voltage criteria during antihypertensive therapy is associated with lower likelihoods of CV morbidity and mortality, independent of blood pressure lowering and treatment modality in persons with essential hypertension. Antihypertensive therapy targeted at regression or prevention of electrocardiographic LVH may improve prognosis.
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| 38. |
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| 39. |
- Schulz, A, et al.
(författare)
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Arctic ozone loss in threshold conditions: Match observations in 1997/1998 and 1998/1999
- 2001
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Ingår i: JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES. - : AMER GEOPHYSICAL UNION. - 0747-7309. ; 106:D7, s. 7495-7503
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Tidskriftsartikel (refereegranskat)abstract
- Chemical ozone loss rates inside the Arctic polar vortex were determined in early 1998 and early 1999 by using the Match technique based on coordinated ozonesonde measurements. These two winters provide the only opportunities in recent years to investigat
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| 40. |
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| 41. |
- Suehrcke, H., et al.
(författare)
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Heat transfer across corrugated sheets and honeycomb transparent insulation
- 2004
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Ingår i: Solar Energy. - : Elsevier BV. - 0038-092X .- 1471-1257. ; 76:1-3, s. 351-358
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes the design of a simple guarded hot-plate apparatus for the measurement of heat transfer across transparent insulation. The apparatus is used to measure the heat transfer coefficient across a transparent corrugated (zigzag) sheet and honeycomb transparent insulation. The sheet and honeycomb are made from cellulose acetate film, which has high absorptance for long-wave thermal radiation and high transmittance for short-wave solar radiation. The corrugated sheet performs well, however, honeycomb transparent insulation of the same height and material appears to be superior due to greater thermal radiation blockage and better solar transmission characteristics. A numerical model for a honeycomb is developed which shows good agreement with the experimentally measured results.
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| 42. |
- von Ossowski, I., et al.
(författare)
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Engineering the exo-loop of Trichoderma reesei cellobiohydrolase, Ce17A. A comparison with Phanerochaete chrysosporium Cel7D
- 2003
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Ingår i: Journal of Molecular Biology. - 0022-2836 .- 1089-8638. ; 333:4, s. 817-829
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Tidskriftsartikel (refereegranskat)abstract
- The exo-loop of Trichoderma reesei cellobiohydrolase Cel7A forms the roof of the active site tunnel at the catalytic centre. Mutants were designed to study the role of this loop in crystalline cellulose degradation. A hydrogen bond to substrate made by a tyrosine at the tip of the loop was removed by the Y247F mutation. The mobility of the loop was reduced by introducing a new disulphide bridge in the mutant D241C/D249C. The tip of the loop was deleted in mutant Delta(G245-Y252). No major structural disturbances were observed in the mutant enzymes, nor was the thermostability of the enzyme affected by the mutations. The Y247F mutation caused a slight k(cat) reduction on 4-nitrophenyl lactoside, but only a small effect on cellulose hydrolysis. Deletion of the tip of the loop increased both k(cat) and K-M and gave reduced product inhibition. Increased activity was observed on amorphous cellulose, while only half the original activity remained on crystalline cellulose. Stabilisation of the exo-loop by the disulphide bridge enhanced the activity on both amorphous and crystalline cellulose. The ratio Glc(2)/(Glc(3) + Glc(1)) released from cellulose, which is indicative of processive action, was highest with Tr Cel7A wild-type enzyme and smallest with the deletion mutant on both substrates. Based on these data it seems that the exo-loop of Tr Cel7A has evolved to facilitate processive crystalline cellulose degradation, which does not require significant conformational changes of this loop.
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