| 1. |
- Abreu, P., et al.
(author)
-
Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
- 2001
-
In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
-
Journal article (peer-reviewed)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.
|
|
| 2. |
- Abreu, P., et al.
(author)
-
Search for sleptons in e+e- collisions at √s = 183 to 189 GeV
- 2001
-
In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 29-42
-
Journal article (peer-reviewed)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.
|
|
| 3. |
- Bratthall, G., et al.
(author)
-
Comparison of ready-to-use EMDOGAIN®-gel and EMDOGAIN® in patients with chronic adult periodontitis. A multicenter clinical study
- 2001
-
In: Journal of Clinical Periodontology. - : John Wiley & Sons. - 0303-6979 .- 1600-051X. ; 28:10, s. 923-929
-
Journal article (peer-reviewed)abstract
- Objectives: The aim of this multicenter trial was to compare the clinical and radiographical outcome of a ready-to-use Emdogain®-gel (test) with the marketed Emdogain® (control). Methods: Subjects with bilateral infrabony defects ≥4 mm deep and ≥2 mm wide according to radiographs were selected. 88 subjects with probing pocket depth (PPD) ≥6 mm ≥1 month after supervised oral hygiene and scaling participated. At baseline plaque index, bleeding on probing, PPD and probing attachment level were recorded and reproducible radiographs for computer-based bone level measurements were taken. In each subject, 1 tooth was randomly treated with the test and 1 tooth with the control gel. Examinations were repeated 8 and 16 months post-operatively. Results: After 16 months, the mean test PPD was 4.1 mm and the mean control PPD 4.2 mm. The mean gain of attachment was 2.7 mm for test and 2.9 mm for the control sites, and the radiographic measurements demonstrated a mean gain of 1 mm for both test and control sites. Conclusion: This series of cases demonstrated a statistically significant reduction of pocket depths and gain of attachment and bone after 8 and 16 months with no difference between the 2 preparations.
|
|
| 4. |
- Ekberg-Jansson, Ann, et al.
(author)
-
Neutrophil-associated activation markers in healthy smokers relates to a fall in DL(CO) and to emphysematous changes on high resolution CT
- 2001
-
In: Respiratory Medicine. - : Elsevier BV. - 0954-6111 .- 1532-3064. ; 95:5, s. 363-373
-
Journal article (peer-reviewed)abstract
- Smoking is a risk factor for developing chronic obstructive pulmonary disease (COPD), but there are no good indicators for early identification of subjects who will develop symptomatic COPD. The aim of this study was to investigate inflammatory mechanisms related to changes in lung function and emphysematous changes on high resolution computed tomography (HRCT) in 'healthy' smokers. Subjects were 60-year-old men from a population study. Bronchoscopy was performed in 30 smokers and 18 who had never smoked. Blood tests, lung function measurements and HRCT were carried out in 58 and 34 subjects, respectively. In comparison with never-smokers, smokers had higher levels of myeloperoxidase (MPO), human neutrophil lipocalin (HNL), eosinophil cationic protein (ECP) and lysozyme in blood, higher levels of MPO, interleukin-8 (IL-8) and HNL in bronchial lavage (BL), and of IL-8, HNL and interleukin-lbeta (IL-1beta) in bronchoalveolar lavage (BAL). Smokers also had lower levels of Clara cell protein 16 (CC-16) in blood. HNL in BL and BAL showed strong correlations to other inflammatory markers (MPO, IL-8, IL-1beta). The variations in MPO in BL were explained by variations in HNL (R2 =0.69), while these variations in BAL were explained by variations in HNL and IL-1beta (R2 = 0.76). DL(CO) was the lung function variable most closely related to MPO and IL-8 in BL and BAL and to IL-1beta in BAL. In a multiple regression analysis, MPO, IL-1beta, IL-8 and CC-16 in BL and MPO in BAL contributed to the explanation of variations in DL(CO) to 41% and 22%. respectively, independent of smoking habits. In smokers with emphysematous lesions on HRCT, HNL in BAL correlated to emphysema score (r(s) = 0.71). We conclude that 'healthy' smoking men with a near normal FEV1 show signs of inflammation in the lower airways that are related to a decrease in DL(CO) and to emphysematous lesions on HRCT. This inflammation seems to be the result of both monocyte/macrophage and neutrophil activation.
|
|
| 5. |
- Ekberg-Jansson, A, et al.
(author)
-
Respiratory symptoms relate to physiological changes and inflammatory markers reflecting central but not peripheral airways. A study in 60-year-old 'healthy' smokers and never-smokers
- 2001
-
In: Respiratory Medicine. - : Elsevier BV. - 1532-3064 .- 0954-6111. ; 95:1, s. 40-47
-
Journal article (peer-reviewed)abstract
- The aim of this study was to evaluate the relationship between respiratory symptoms, lung function and inflammatory markers in 'healthy' smokers. The study population was recruited from an epidemiological study with subjects of the same age, 60 years. Only smokers who considered themselves healthy (n=58) and a random sample of never-smokers (n=34) were investigated. All subjects underwent lung function tests--spirometry, carbon monoxide transfer (DLco) and the single-breath N2 method (N2 test)--together with high-resolution computed tomography (HRCT). A flexible bronchoscopy with a bronchoalveolar lavage (BAL) was performed in 30 smokers and 18 never-smokers. Bronchial biopsies were also taken. Smokers who reported non-specific respiratory problems, chronic bronchitis and wheezing in a symptom questionnaire had a lower forced expiratory volume in 1 sec (FEV1), FEV% and specific airway conductance (sGaw), lung function tests supposed to reflect the more central airways, than smokers without respiratory symptoms. A limited number of smokers with occasional non-specific respiratory problems also had more cytotoxic T cells (CD8) in bronchial biopsies. No differences were found in DLCO and the N2 test, lung function tests supposed to reflect the more peripheral airways including the alveoli, HRCT-diagnosed emphysema or inflammatory markers in blood and BAL between smokers with and without respiratory symptoms. It is concluded that even when smokers consider themselves 'healthy' they have mild symptoms that are related more to physiological changes and inflammatory markers that may reflect events in the central airways than to changes that may reflect events in the peripheral airways.
|
|
| 6. |
|
|
| 7. |
- Assarsson, Maria, et al.
(author)
-
Restoring proper radical generation by azide binding to the iron site of the E238A mutant R2 protein of ribonucleotide reductase from Escherichia coli.
- 2001
-
In: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 276:29, s. 26852-26859
-
Journal article (peer-reviewed)abstract
- The enzyme activity of Escherichia coli ribonucleotide reductase requires the presence of a stable tyrosyl free radical and diiron center in its smaller R2 component. The iron/radical site is formed in a reconstitution reaction between ferrous iron and molecular oxygen in the protein. The reaction is known to proceed via a paramagnetic intermediate X, formally a Fe(III)-Fe(IV) state. We have used 9.6 GHz and 285 GHz EPR to investigate intermediates in the reconstitution reaction in the iron ligand mutant R2 E238A with or without azide, formate, or acetate present. Paramagnetic intermediates, i.e. a long-living X-like intermediate and a transient tyrosyl radical, were observed only with azide and under none of the other conditions. A crystal structure of the mutant protein R2 E238A/Y122F with a diferrous iron site complexed with azide was determined. Azide was found to be a bridging ligand and the absent Glu-238 ligand was compensated for by azide and an extra coordination from Glu-204. A general scheme for the reconstitution reaction is presented based on EPR and structure results. This indicates that tyrosyl radical generation requires a specific ligand coordination with 4-coordinate Fe1 and 6-coordinate Fe2 after oxygen binding to the diferrous site.
|
|
| 8. |
|
|
| 9. |
- Engelmark, O., et al.
(author)
-
Ecological effects and management aspects of an exotic tree species : the case of lodgepole pine in Sweden
- 2001
-
In: Forest Ecology and Management. - 0378-1127 .- 1872-7042. ; 141:02-jan, s. 3-13
-
Journal article (peer-reviewed)abstract
- The North American tree Pinus contorta var, latifolia was experimentally introduced in Sweden already in the 1920s, and has been used in Swedish forestry on a large scale since the 1970s. These plantations now cover 565,000 ha, mainly in the northern area. In this paper we summarize and discuss existing ecological knowledge of this species introduction. With regard to longterm sustainability we suggest management means to minimize harmful effects of the introduction on ecosystems. These include aspects of self dispersal, pests, ecosystem and landscape structures, and also ecological processes and biodiversity. We also focus on observed and possible interactions in the ecosystems. As Pinus contorta seeds are disseminated and trees regenerated outside initial plantations, this may have future bearings on biodiversity. We suggest a strategy which takes account of the uncertainty in predicting future ecological effects. The strategy includes areal restrictions and zones without Pinus contorta, but also to set up a monitoring program. Observations of adverse effects from the plantations would then give the possibility to adjust P. contorta management.
|
|
| 10. |
|
|
