| 1. |
- Abreu, P., et al.
(författare)
-
Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets
- 2000
-
Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 13:4, s. 573-589
-
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..
|
|
| 2. |
- Abreu, P., et al.
(författare)
-
Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
- 2001
-
Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
-
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.
|
|
| 3. |
|
|
| 4. |
- Bower, K. N., et al.
(författare)
-
ACE-2 HILLCLOUD. An overview of the ACE-2 ground-based cloud experiment
- 2000
-
Ingår i: Tellus. Series B: Chemical and Physical Meteorology. - : Stockholm University Press. - 0280-6509. ; 52:2, s. 750-778
-
Tidskriftsartikel (refereegranskat)abstract
- The ACE-2 HILLCLOUD experiment was carried out on the island of Tenerife in June-July 1997 to investigate the interaction of the boundary layer aerosol with a hill cap cloud forming over a ridge to the north-east of the island. The cloud was used as a natural flow through reactor to investigate the dependence of the cloud microphysics and chemistry on the characteristics of the aerosols and trace gases entering cloud, and to simultaneously study the influence of the physical and chemical processes occurring within the cloud on the size distribution, chemical and hygroscopic properties of the aerosol exiting cloud. 5 major ground base sites were used, measuring trace gases and aerosols upwind and downwind of the cloud, and cloud microphysics and chemistry and interstitial aerosol and gases within the cloud on the hill. 8 intensive measurement periods or runs were undertaken during cloud events, (nocturnally for seven of the eight runs) and were carried out in a wide range of airmass conditions from clean maritime to polluted continental. Polluted air was characterised by higher than average concentrations of ozone (> 50 ppbv), fine and accumulation mode aerosols (> 3000 and > 1500 cm -3 , respectively) and higher aerosol mass loadings. Cloud droplet number concentrations N, increased from 50 cm -3 in background maritime air to > 2500 cm -3 in aged polluted continental air, a concentration much higher than had previously been detected. Surprisingly, N was seen to vary almost linearly with aerosol number across this range. The droplet aerosol analyser (DAA) measured higher droplet numbers than the corrected forward scattering spectrometer probe (FSSP) in the most polluted air, but at other times there was good agreement (FSSP = 0.95 DAA with an r 2 = 0.89 for N < 1200 cm -3 ). Background ammonia gas concentrations were around 0.3 ppbv even in air originating over the ocean, another unexpected but important result for the region. NO 2 was present in background concentrations of typically 15 pptv to 100 pptv and NO 3 . (the nitrate radical) was observed at night throughout. Calculations suggest NO 3 . losses were mainly by reaction with DMS to produce nitric acid. Low concentrations of SO 2 (~30 pptv), HNO 3 and HCl were always present. HNO 3 concentrations were higher in polluted episodes and calculations implied that these exceeded those which could be accounted for by NO 2 oxidation. It is presumed that nitric and hydrochloric acids were present as a result of outgassing from aerosol, the HNO 3 from nitrate rich aerosol transported into the region from upwind of Tenerife, and HCl from sea salt aerosol newly formed at the sea surface. The oxidants hydrogen peroxide and ozone were abundant (i.e., were well in excess over SO 2 throughout the experiment). Occasions of significant aerosol growth following cloud processing were observed, particularly in cleaner cases. Observations and modelling suggested this was due mainly to the take up of nitric acid, hydrochloric acid and ammonia by the smallest activated aerosol particles. On a few occasions a small contribution was made by the in-cloud oxidation of S(IV). The implications of these results from HILLCLOUD for the climatologically more important stratocumulus Marine Boundary Layer (MBL) clouds are considered.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Bergthorsson, J.T., et al.
(författare)
-
BRCA1 and BRCA2 mutation status and cancer family history of Danish women affected with multifocal or bilateral breast cancer at a young age
- 2001
-
Ingår i: Journal of Medical Genetics. - : BMJ. - 0022-2593 .- 1468-6244. ; 38:6, s. 361-368
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction - A small fraction of breast cancer is the result of germline mutations in the BRCA1 and BRCA2 cancer susceptibility genes. Mutation carriers frequently have a positive family history of breast and ovarian cancer, are often diagnosed at a young age, and may have a higher incidence of double or multiple primary breast tumours than breast cancer patients in general. Objectives - To estimate the prevalence and spectrum of BRCA1 and BRCA2 mutations in young Danish patients affected with bilateral or multifocal breast cancer and to determine the relationship of mutation status to family history of cancer. Subjects - From the files of the Danish Breast Cancer Cooperative Group (DBCG), we selected 119 breast cancer patients diagnosed before the age of 46 years with either bilateral (n=59) or multifocal (n=61) disease. Methods - DNA from the subjects was screened for BRCA1 and BRCA2 mutations using single strand conformation analysis (SSCA) and the protein truncation test (PTT). Observed and expected cancer incidence in first degree relatives of the patients was estimated using data from the Danish Cancer Registry. Results - Twenty four mutation carriers were identified (20%), of whom 13 had a BRCA1 mutation and 11 carried a BRCA2 mutation. Two mutations in BRCA1 were found repeatedly in the material and accounted for seven of the 24 (29%) mutation carriers. The mutation frequency was about equal in patients with bilateral (22%) and multifocal breast cancer (18%). The incidence of breast and ovarian cancer was greatly increased in first degree relatives of BRCA1 and BRCA2 mutation carriers, but to a much lesser degree in relatives of non-carriers. An increased risk of cancer was also noted in brothers of non-carriers. Conclusions - A relatively broad spectrum of germline mutations was observed in BRCA1 and BRCA2 and most of the mutations are present in other populations. Our results indicate that a diagnosis of bilateral and multifocal breast cancer is predictive of BRCA1 and BRCA2 mutation status, particularly when combined with information on the patients' age at diagnosis and family history of breast/ovarian cancer.
|
|
| 11. |
|
|
| 12. |
- Hoffmann, L., et al.
(författare)
-
Weakly bound carbon-hydrogen complex in silicon
- 2000
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 61:24, s. 16659-16666
-
Tidskriftsartikel (refereegranskat)abstract
- Local vibrational modes of a weakly bound carbon-hydrogen complex in silicon have been identified with infrared-absorption spectroscopy. After implantation of protons at ∼20 K and subsequent annealing at 180 K, two carbon modes at 596 and 661 cm-1, and one hydrogen mode at 1885 cm-1 are observed. The three modes originate from the same complex, which is identified as bond-centered hydrogen in the vicinity of a nearby substitutional carbon atom. Ab initio theory has been applied to calculate the structure and local modes of carbon-hydrogen complexes with hydrogen located at the first, second, and third nearest bond-center site to substitutional carbon. The results support our assignment.
|
|
| 13. |
- Jacobsson, A., et al.
(författare)
-
The effect of packaging material on the sensory properties of broccoli.
- 2003
-
Ingår i: ISHS Acta Horticulturae. - 0567-7572. ; 599, s. 323-323
-
Konferensbidrag (refereegranskat)abstract
- Three different commercially available polymeric films were studied to determine their effect on the sensory properties of fresh broccoli (Brassica oleracea L. var. Italica cv. ‘Marathon’). The polymer materials investigated were oriented polypropylene (OPP), polyvinyl chloride (PVC) and one low density polyethylene (LDPE) which contained an ethylene absorber. The fresh broccoli was packaged and stored for one week at 10°C or 3 days at 4°C followed by 4 days at 10°C. The oxygen and carbon dioxide concentrations inside the packages were monitored during storage. After storage the broccoli was evaluated according to sensory analyses, i.e. triangle test and quantitative descriptive analysis, by an analytical panel. The panel judged the broccoli according to smell, taste, texture and appearance. The triangle test showed significant differences between the smell of the broccoli samples, stored in the different packaging materials, when cooked. However, no differences between the raw broccoli, stored in the different packaging materials could be detected. The quantitative descriptive analysis showed that the following attributes; fresh smell and taste, chewing resistance, and crispness, differed significantly between the packaged broccoli when cooked. The appearance was shown to be the sensory property of broccoli most affected by the storage conditions, i.e. packaging material used and storage temperature. The results indicated the importance of the packaging material for maintaining the broccoli quality. However, one packaging material that was able to maintain all the studied sensory properties could not be identified.
|
|
| 14. |
- Lavrov, E.V., et al.
(författare)
-
Combined infrared absorption and modeling study of a dicarbon-dihydrogen defect in silicon
- 2000
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 62:19, s. 12859-12867
-
Tidskriftsartikel (refereegranskat)abstract
- Crystalline silicon samples doped with carbon were irradiated with electrons and subsequently implanted with protons. Infrared-absorption measurements revealed local modes of hydrogen and carbon at 2967.4, 911.7, and 654.7 cm-1, which originate from the same defect. Measurements on samples codoped with different carbon and hydrogen isotopes showed that the defect contains two equivalent carbon and two equivalent hydrogen atoms. From uniaxial stress measurements, the defect is found to display trigonal symmetry. Ab initio local-density-functional theory was applied to calculate the structure and local vibrational modes of defects with pairs of equivalent carbon and hydrogen atoms. Based on these results, the observed local modes are ascribed to a defect with two adjacent substitutional carbon atoms, each of which binds a hydrogen atom located between the carbon atoms.
|
|
| 15. |
- Lavrov, E. V., et al.
(författare)
-
Local vibrational modes of two neighboring substitutional carbon atoms in silicon
- 2000
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 62:1, s. 158-165
-
Tidskriftsartikel (refereegranskat)abstract
- Infrared absorption measurements on n-type silicon doped with carbon and irradiated with electrons at room temperature have revealed new absorption lines at 527.4 and 748.7 cm-1, which originate from the same defect. The 748.7-cm-1 line is observed only when the sample is cooled in the dark and the spectrum is measured through a low-pass filter with cutoff frequency below 6000 cm-1. Light with frequency above 6000 cm-1 removes this line and generates the 527.4-cm-1 line. Comparison with spectra recorded on irradiated silicon doped with 13C shows that the two lines represent local vibrational modes of carbon. The annealing behavior of the 748.7-cm-1 line is identical to that of the EPR signal originating from the negative charge state of two adjacent substitutional carbon atoms (Cs-Cs)-. The 527.4- and 748.7-cm-1 lines are ascribed to the E modes of Cs-Cs in the neutral and negative charge states, respectively. The structure and local vibrational modes of (Cs-Cs)0 and (Cs-Cs)- have been calculated by ab initio local density functional theory. The calculated structures agree qualitatively with those obtained previously by Hartree-Fock methods, but the calculated Si-C and C-C bond lengths differ somewhat. The calculated local mode frequencies are in good agreement with those observed. The formation of Cs-Cs has also been investigated. It is suggested that the center is formed when a vacancy is trapped by the metastable substitutional carbon-interstitial carbon center, Cs-Ci.
|
|
| 16. |
- Skari, H, et al.
(författare)
-
Congenital diaphragmatic hernia: a survey of practice in Scandinavia
- 2004
-
Ingår i: Pediatric Surgery International. - : Springer Science and Business Media LLC. - 1437-9813 .- 0179-0358. ; 20:5, s. 309-313
-
Tidskriftsartikel (refereegranskat)abstract
- There is no consensus on the treatment of congenital diaphragmatic hernia (CDH), and practice seems to vary between centres. The main purpose of the present study was to survey current practice in Scandinavia. Thirteen paediatric surgical centres serving a population of about 22 million were invited, and all participated. One questionnaire was completed at each centre. The questionnaire evaluated management following prenatal diagnosis, intensive care strategies, operative treatment, and long-term follow-up. Survival data (1995-1998) were available from 12 of 13 centres. Following prenatal diagnosis of CDH, vaginal delivery and maternal steroids were used at eight and six centres, respectively. All centres used high-frequency oscillation ventilation (HFOV), nitric oxide (NO), and surfactant comparatively often. Five centres had extracorporeal membrane oxygenation (ECMO) facilities, and four centres transferred ECMO candidates. The majority of centres (7/9) always tried HFOV before ECMO was instituted. Surgery was performed when the neonate was clinically stable (11/13) and when no signs of pulmonary hypertension were detected by echo-Doppler (6/13). The repair was performed by laparotomy at all centres and most commonly with nonabsorbable sutures (8/13). Thoracic drain was used routinely at seven centres. Long-term follow-up at a paediatric surgical centre was uncommon (3/13). Only three centres treated more than five CDH patients per year. Comparing survival in centres treating more than five with those treating five or fewer CDH patients per year, there was a tendency towards better survival in the higher-volume centres (72.4%) than in the centres with lower volume (58.7%), p =0.065.
|
|
| 17. |
|
|
| 18. |
- Albin, Maria, et al.
(författare)
-
Incidence of asthma in female Swedish hairdressers.
- 2002
-
Ingår i: Occupational and Environmental Medicine. - : BMJ. - 1470-7926 .- 1351-0711. ; 59:2, s. 119-23.
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To investigate the risk of asthma in hairdressers. METHODS: The incidence of asthma was retrospectively estimated in a Swedish nationwide study including all female hairdressers certified from vocational schools from 1970 to 1995, and a stratified sample of women from the general population were referents. A postal questionnaire included questions on respiratory tract symptoms, atopy, smoking, working periods as a hairdresser, and number of specific hair treatments performed/week. Reported exposures were validated by occupational hygienists. Rate ratios of incidence (IRRs) of asthma were estimated by Poisson regression, adjusted for calendar year of observation, hay fever, smoking, and region of domicile. RESULTS: The crude incidences of asthma/1000 person-years were: 3.9 during active years as a hairdresser, 2.8 among the hairdressers when not working in the profession, and 3.1 among the referents. The corresponding IRR for being an active hairdresser compared with the referents was 1.3 (95% confidence interval (95% CI) 1.0 to 1.6). Moderate effects on risk of asthma were found both from hairdressing work (IRR=1.6 (1.1 to 2.2) among never-smokers) and from smoking (IRR=1.6 (1.2 to 2.2) among referents). However, the combined effect from hairdressing work and smoking (IRR=1.5 (1.0 to 2.1)) was less than expected (p=0.02). No effect modification by respiratory atopy was found. The hairdressers most often performing hair bleaching treatments (IRR=1.5 (0.7 to 3.0)) or using hair spray (IRR=1.4 (0.8 to 2.4)) had, compared with the most infrequent users, a slightly, but not significantly higher incidence of asthma. Exposure to persulphates in hair bleach was estimated to be 0.04-0.15 mg/m(3) during mixing of the powder. Reported average number of bleaching treatments agreed well with those performed according to a diary. CONCLUSIONS: Active hairdressing work was associated with a moderately increased incidence of asthma among lifelong non-smokers. The results are moderately supportive, but not conclusive, of associations between asthma and exposure to hair bleach or hair spray.
|
|
| 19. |
- Andersen, O., et al.
(författare)
-
Electrical activity of carbon-hydrogen centers in Si
- 2002
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 66:23, s. 235205-1
-
Tidskriftsartikel (refereegranskat)abstract
- The electrical activity of Cs-H defects in Si has been investigated in a combined modeling and experimental study. High-resolution Laplace capacitance spectroscopy with the uniaxial stress technique has been used to measure the stress-energy tensor and the results are compared with theoretical modeling. At low temperatures, implanted H is trapped as a negative-U center with a donor level in the upper half of the gap. However, at higher temperatures, H migrates closer to the carbon impurity and the donor level falls, crossing the gap. At the same time, an acceptor level is introduced into the upper gap making the defect a positive-U center.
|
|
| 20. |
- Andersen, Ole, et al.
(författare)
-
Nutritional interactions in intestinal cadmium uptake--possibilities for risk reduction.
- 2004
-
Ingår i: Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine. - : Kluwer Academic Publishers. - 0966-0844 .- 1572-8773. ; 17:5, s. 543-7
-
Tidskriftsartikel (refereegranskat)abstract
- Effects of dietary composition and trace element status on fractional intestinal cadmium uptake is reviewed below. Fractional cadmium uptake is of fundamental importance for internal dose, related individual susceptibility to cadmium, induced renal damage and eventually bone disease. Diet composition with regard to macronutrients has some effects on cadmium bioavailability. Major determinants of intestinal cadmium uptake are however diet composition with regard to crude fibres and trace elements, especially iron. Deficiencies may increase intestinal cadmium uptake 5-8 times. Ultimate risk management would be not to raise crops on cadmium polluted soil. Provisionally, assurance of optimal trace element statusin persons exposed to cadmium is essential for risk reduction.
|
|
| 21. |
- Andersen, O., et al.
(författare)
-
Piezospectroscopic analysis of the hydrogen-carbon complexes in silicon
- 2001
-
Ingår i: Physica. B, Condensed matter. - 0921-4526 .- 1873-2135. ; 308, s. 139-142
-
Tidskriftsartikel (refereegranskat)abstract
- We have observed the donor (Ec-0.22 eV) and acceptor (Ec-0.16 eV) levels related to hydrogen-carbon complexes in silicon. The donor level is only detected at low temperatures after proton implantation. This hydrogen-carbon complex irreversibly reconfigures at temperatures above 225 K to a configuration characterized by the acceptor level, which is stable up to room temperature. The same acceptor level is also observed after atomic hydrogen diffusion. We have used Laplace transform deep level transient spectroscopy (DLTS) to show the influence of uniaxial stress on the electron emission process and the effect of the stress-induced alignment for the acceptor state. The pattern of the Laplace DLTS peak splittings indicate a trigonal symmetry of the defect. First principles calculations were carried out on the hydrogen-carbon defects with a view of determining their electrical levels and stress response for comparison with the experimental results.
|
|
| 22. |
|
|
| 23. |
|
|
| 24. |
- Bensch, Staffan, et al.
(författare)
-
Partial albinism in a semi-isolated population of great reed warblers
- 2000
-
Ingår i: Hereditas. - : Springer Science and Business Media LLC. - 1601-5223 .- 0018-0661. ; 133:2, s. 167-170
-
Tidskriftsartikel (refereegranskat)abstract
- Albinism in birds is thought to result from the expression of recessive alleles that disrupt melanin pigmentation at feather development. We have studied great reed warblers Acrocephalus arundinaceus in a recently founded and increasing population in Sweden during 15 years for the presence of birds with albinistic feathers. The study population was founded in 1978 and the few cases of albinism was exclusively recorded during the first five pears of our study (1985-1989). This fits to the expected pattern if albinism is governed by recessive alleles; we have previously demonstrated that the population suffered from inbreeding during the first years of our study. The albinistic birds experienced a similar lifetime reproductive success as normally coloured birds.
|
|
| 25. |
|
|
| 26. |
|
|
| 27. |
|
|
| 28. |
- Brisman, Jonas, 1954, et al.
(författare)
-
The incidence of respiratory symptoms in female Swedish hairdressers
- 2003
-
Ingår i: American Journal of Industrial Medicine. - : Wiley. - 0271-3586. ; 44:6, s. 673-8.
-
Tidskriftsartikel (refereegranskat)abstract
- Background Airway diseases in hairdressers are a concern. The objective of this investigation is to evaluate the risk for three respiratory symptoms, wheeze, dry cough, and nasal blockage, in hairdressers. Methods A questionnaire on respiratory symptoms, atopy, smoking, and work history was answered by 3,957 female hairdressers and 4,905 women from the general population as referents. Incidence rates (IR) and incidence rate ratios (IRRs)for the three symptoms were estimated. Results The IRs of all three studied symptoms were higher in the hairdressers compared with the referents. Smoking modified the effects of cohort affiliationfor all threesymptoms; the combined effect from hairdressing work and smoking was less than expected. In addition, the effect of cohort affiliation for wheeze was also modified by atopy, and the effect of cohort affiliation for nasal blockage was also modified by calendar year. Conclusions Hairdressing work was associated with increased incidences of respiratory symptoms. Smoking had a negative modifying effect.
|
|
| 29. |
- Brunner, M, et al.
(författare)
-
Ambient networks management challenges and approaches
- 2004
-
Ingår i: MOBILITY AWARE TECHNOLOGIES AND APPLICATIONS, PROCEEDINGS. - BERLIN : SPRINGER. - 3540234233 ; , s. 196-216
-
Konferensbidrag (refereegranskat)abstract
- System management addresses the provision of functions required for controlling, planning, allocating, monitoring, and deploying the resources of a network and of its services in order to optimize its efficiency and productivity and to safeguard its operation. It is also an enabler for the creation and sustenance of new business models and value chains, reflecting the different roles the service providers and users of a network can assume. Ambient Network represents a new networking approach and it aims to enable the cooperation of heterogeneous networks, on demand and transparently, to the potential users, without the need for pre-configuration or offline negotiation between network operators. To achieve these goals, ambient network management systems have to become dynamic, adaptive, autonomic and responsive to the network and its ambience. This paper discusses relationships between the concepts of autonomous and self-manageability and those of ambient networking, and the challenges and benefits that arise from their employment.
|
|
| 30. |
- Christensen, B M, et al.
(författare)
-
Localization and regulation of PKA-phosphorylated AQP2 in response to V(2)-receptor agonist/antagonist treatment.
- 2000
-
Ingår i: American journal of physiology. Renal physiology. - 1931-857X. ; 278:1, s. F29-42
-
Tidskriftsartikel (refereegranskat)abstract
- Phosphorylation of Ser(256), in a PKA consensus site, in AQP2 (p-AQP2) appears to be critically involved in the vasopressin-induced trafficking of AQP2. In the present study, affinity-purified antibodies that selectively recognize AQP2 phosphorylated at Ser(256) were developed. These antibodies were used to determine 1) the subcellular localization of p-AQP2 in rat kidney and 2) changes in distribution and/or levels of p-AQP2 in response to [desamino-Cys(1),D-Arg(8)]vasopressin (DDAVP) treatment or V(2)-receptor blockade. Immunoelectron microscopy revealed that p-AQP2 was localized in both the apical plasma membrane and in intracellular vesicles of collecting duct principal cells. Treatment of rats with V(2)-receptor antagonist for 30 min resulted in almost complete disappearance of p-AQP2 labeling of the apical plasma membrane with only marginal labeling of intracellular vesicles remaining. Immunoblotting confirmed a marked decrease in p-AQP2 levels. In control Brattleboro rats (BB), lacking vasopressin secretion, p-AQP2 labeling was almost exclusively present in intracellular vesicles. Treatment of BB rats with DDAVP for 2 h induced a 10-fold increase in p-AQP2 labeling of the apical plasma membrane. The overall abundance of p-AQP2, however, was not increased, as determined both by immunoelectron microscopy and immunoblotting. Consistent with this, 2 h of DDAVP treatment of normal rats also resulted in unchanged p-AQP2 levels. Thus the results demonstrate that AQP2 phosphorylated in Ser(256) is present in the apical plasma membrane and in intracellular vesicles and that both the intracellular distribution/trafficking, as well as the abundance of p-AQP2, are regulated via V(2) receptors by altering phosphorylation and/or dephosphorylation of Ser(256) in AQP2.
|
|
| 31. |
|
|
| 32. |
- Eerola, Paula, et al.
(författare)
-
The Nordugrid production grid infrastructure, status and plans
- 2003
-
Ingår i: Proceedings. Fourth International Workshop on Grid Computing. - 076952026X ; , s. 158-165
-
Konferensbidrag (refereegranskat)abstract
- Nordugrid offers reliable grid services for academic users over an increasing set of computing & storage resources spanning through the Nordic countries Denmark, Finland, Norway and Sweden. A small group of scientists has already been using the Nordugrid as their daily computing utility. In the near future we expect a rapid growth both in the number of active users and available resources thanks to the recently launched Nordic grid projects.We report on the present status and short term plans of the Nordic grid infrastructure and describe the available and foreseen resources, grid services and our forming user base
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
- Grunert, K.G., et al.
(författare)
-
Consumer perceptions of food products involving genetic modification : Results from a qualitative study in four Nordic countries
- 2001
-
Ingår i: Food Quality and Preference. - 0950-3293 .- 1873-6343. ; 12:8, s. 527-542
-
Tidskriftsartikel (refereegranskat)abstract
- Product descriptions of cheese, candy and salmon products were presented to samples of respondents in four Nordic countries. The descriptions represented various applications of genetic modification (GM), varied along a 'distance' dimension and a 'what is modified' dimension, and were presented along with a conventionally produced product. Respondents ranked the products according to preference, and their perceptions were ascertained by the laddering method. Results indicate that respondents regard 'non-GM' as a value in itself, and associate the use of GM with a host of negative consequences and risks, but mostly with uncertainty and unhealthiness. Benefits of the use of GM were perceived and regarded as relevant, but could not compensate for the negative associations. The 'distance' dimension had a clear impact on consumer preferences, whereas the 'what is modified' dimension had effects which were product specific. © 2001 Elsevier Science Ltd.
|
|
| 37. |
- Hansson, Bengt, et al.
(författare)
-
Restricted dispersal in a long-distance migrant bird with patchy distribution, the great reed warbler
- 2002
-
Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 1432-1939 .- 0029-8549. ; 130:4, s. 536-542
-
Tidskriftsartikel (refereegranskat)abstract
- In patchily distributed species dispersal connects local populations into metapopulations. Reliable quantifications of dispersal are therefore crucial to understanding the population dynamics and genetic structure of such metapopulation systems. The great reed warbler (Acrocephalus arundinaceus) inhabits eutrophic lakes and has a patchy breeding distribution. In this study we investigated the dispersal pattern of the great reed warbler based on an extensive capture-recapture effort covering a large census area (22,500 km(2)). At two adjacent breeding sites (10 km apart) in southern Central Sweden, the "main study area", we ringed the majority of adult and nestling great reed warblers between 1902 and 1999. In 1998 and 1999, we opportunistically searched for territorial males at the majority of the Swedish breeding sites, and were able to examine about 56% of all males in the region. Analyses of recaptured males demonstrated that philopatry predominated. Sixty-nine percent of the recruiting nestlings returned to breed in the main study area (their natal area), and 92% of the resighted adults were found at the same breeding locality in both study years. Breeding dispersal was significantly more restricted than natal dispersal. Additional data on natal and breeding dispersal within the main study area in 1992-1999 suggested that females were as philopatric as males. The overall high level of philopatry, with only occasional longer dispersal distances documented, yielded a root-mean-square dispersal distance of 33 km per generation. High philopatry, short dispersal distances and similar dispersal patterns of male and female great reed warblers contrast the findings among birds in general, but conform to data of species having patchy breeding habitat and isolated populations. Restricted dispersal suggests limited gene flow even among several Swedish populations, which is in line with some previous findings of the population ecology of the great reed warbler: (1) structured mtDNA lineages among European populations (2) small-scale population differences in song patterns; and (3) low genetic variation and occurrence of inbreeding depression in our main study population.
|
|
| 38. |
|
|
| 39. |
- Leveque, Patrick, et al.
(författare)
-
Vacancy and interstitial depth profiles in ion-implanted silicon.
- 2003
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 93:2, s. 871-877
-
Tidskriftsartikel (refereegranskat)abstract
- An experimental method of studying shifts between concentration-versus-depth profiles of vacancy- and interstitial-type defects in ion-implanted silicon is demonstrated. The concept is based on deep level transient spectroscopy measurements utilizing the filling pulse variation technique. The vacancy profile, represented by the vacancy-oxygen center, and the interstitial profile, represented by the interstitial carbon-substitutional carbon pair, are obtained at the same sample temperature by varying the duration of the filling pulse. The effect of the capture in the Debye tail has been extensively studied and taken into account. Thus, the two profiles can be recorded with a high relative depth resolution. Using low doses, point defects have been introduced in lightly doped float zone n-type silicon by implantation with 6.8 MeV boron ions and 680 keV and 1.3 MeV protons at room temperature. The effect of the angle of ion incidence has also been investigated. For all implantation conditions the peak of the interstitial profile is displaced towards larger depths compared to that of the vacancy profile. The amplitude of this displacement increases as the width of the initial point defect distribution increases. This behavior is explained by a simple model where the preferential forward momentum of recoiling silicon atoms and the highly efficient direct recombination of primary point defects are taken into account.
|
|
| 40. |
- Mammen, C.B., et al.
(författare)
-
Bent Diamond Crystals and Multilayer Based Optics at the new 5-Station Protein Crystallography Beamline ‘Cassiopeia’ at MAX-lab
- 2004
-
Ingår i: AIP Conference Proceedings. - : AIP. - 0094-243X. - 0735401799 ; 705:1, s. 808-811
-
Konferensbidrag (refereegranskat)abstract
- A new 5-station beamline for protein crystallography is being commissioned at the Swedish synchrotron light source MAX-II at Lund University. Of the 2K/gamma = 14 mrad horizontal wiggler fan, the central 2 mrad are used and split in three parts. The central 1 mrad will be used for a station optimized for MAD experiments and on each side of the central fan, from 0.5 mrad to 1 mrad, there are two fixed energy stations using different energies of the same part of the beam. These, in total five stations, can be used simultaneously and independently for diffraction data collection. The two upstream monochromators for the side stations are meridionally bent asymmetric diamond(111) crystals in Laue transmission geometry. The monochromators for the downstream side stations are bent Ge(111) crystals in asymmetric Bragg reflection geometry. Curved multilayer mirrors inserted in the monochromatic beams provide focusing in the vertical plane. The first side station is under commissioning, and a preliminary test protein data set has been collected. ©2004 American Institute of Physics
|
|
| 41. |
- Mammen, C B, et al.
(författare)
-
Design of a 5-station macromolecular crystallography beamline at MAX-Lab
- 2002
-
Ingår i: Acta Physica Polonica. Series A: General Physics, Physics of Condensed Matter, Optics and Quantum Electronics, Atomic and Molecular Physics, Applied Physics. - 0587-4246. ; 101:5, s. 595-602
-
Tidskriftsartikel (refereegranskat)abstract
- A beamline for macromolecular crystallography is under construction at the Swedish synchrotron light source MAX-lab at Lund University in a collaborative effort between Denmark and Sweden. Of the 7 mrad horizontal wiggler fan emitted from the new superconducting multipole wiggler, the central 2 mrad will be used and split in three parts. The central 1 mrad will be used for a tunable station optimised for multi-wavelength anomalous diffraction experiments and on each side of the central fan there will be two fixed wavelength stations using different energies of the same part of the beam. These in total five stations can be used simultaneously and independently for collecting diffraction data.
|
|
| 42. |
|
|
| 43. |
|
|
| 44. |
- Martin, David M., et al.
(författare)
-
Bistable defect in mega-electron-volt proton implanted 4H silicon carbide
- 2004
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 84:10, s. 1704-1706
-
Tidskriftsartikel (refereegranskat)abstract
- Epitaxial 4H-SiC n-type layers implanted at room temperature with a low fluence of mega-electron-volt protons have been measured by deep level transient spectroscopy (DLTS). The proton fluence of 1x10(12) cm(-2) creates an estimated initial concentration of intrinsic point defects of about 10(14) cm(-3) of which about 10% remain after the implantation and gives rise to deep states in the upper part of the band gap. Here, we investigate the samples prior to high-temperature annealing and a very complex spectrum is revealed. In particular, a bistable defect M is discovered having two DLTS peaks, M-1 and M-3 at E-C-0.42 and around E-C-0.75 eV, respectively, in one configuration and one peak, M-2 at E-C-0.70 eV in the other configuration. The charge dependent thermal activation energies for the transformation between the bistable defect peaks are 0.90 and 1.40 eV.
|
|
| 45. |
- Moeller, Kasper, et al.
(författare)
-
Pyruvate decarboxylases from the petite-negative yeast Saccharomyces kluyveri
- 2004
-
Ingår i: Molecular Genetics and Genomics. - : Springer Science and Business Media LLC. - 1617-4615 .- 1617-4623. ; 270:6, s. 558-568
-
Tidskriftsartikel (refereegranskat)abstract
- Saccharomyces kluyveri is a petite-negative yeast, which is less prone to form ethanol under aerobic conditions than is S. cerevisiae. The first reaction on the route from pyruvate to ethanol is catalysed by pyruvate decarboxylase, and the differences observed between S. kluyveri and S. cerevisiae with respect to ethanol formation under aerobic conditions could be caused by differences in the regulation of this enzyme activity. We have identified and cloned three genes encoding functional pyruvate decarboxylase enzymes ( PDC genes) from the type strain of S. kluyveri (Sk-PDC11, Sk-PDC12 and Sk-PDC13). The regulation of pyruvate decarboxylase in S. kluyveri was studied by measuring the total level of Sk-PDC mRNA and the overall enzyme activity under various growth conditions. It was found that the level of Sk-PDC mRNA was enhanced by glucose and oxygen limitation, and that the level of enzyme activity was controlled by variations in the amount of mRNA. The mRNA level and the pyruvate decarboxylase activity responded to anaerobiosis and growth on different carbon sources in essentially the same fashion as in S. cerevisiae. This indicates that the difference in ethanol formation between these two yeasts is not due to differences in the regulation of pyruvate decarboxylase(s), but rather to differences in the regulation of the TCA cycle and the respiratory machinery. However, the PDC genes of Saccharomyces/Kluyveromyces yeasts differ in their genetic organization and phylogenetic origin. While S. cerevisiae and S. kluyveri each have three PDC genes, these have apparently arisen by independent duplications and specializations in each of the two yeast lineages.
|
|
| 46. |
- Nielsen, Heidi B., et al.
(författare)
-
Gravhøje som øer i agerlandet: Forandringer i floraen 1961 til 2000
- 2003
-
Ingår i: Flora og Fauna. - 0015-3818. ; 109:3-4, s. 95-100
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- A published investigation in 1961 of the vegetation on 10 burial mounds in southern Zealand was repeated in 2000. The burial mounds were situated as islands in the intensively used arable landscape. It is likely that such small fragments receive great inputs of Nitrogen by wet deposition and spill-over of artificial fertiliser from the surrounding fields. It was hypothesised that burial mounds in close contact with arable farming should show early signs of effects upon vegetation of eutrophication, and potentially warn of long-term changes in more coherent habitat areas of similar kind. We analysed the data by Detrended Correspondence Analysis (DCA), and compared the sample scores from the two surveys by pairwise t-tests. The DCA-axes were interpreted in terms of measured and calibrated environmental parameters, soil pH, soil type, cover of woody plants, and calibrated Ellenberg N-value. It was found that a significant change in the species composition had taken place. Nitrophilic and shade-tolerant species had increased significantly. Common species typical of dry grassland and heathland had decreased in abundance, and rarer species had disappeared altogether. The vegetation changes are discussed in terms of changed agricultural land-use and ceased grazing.
|
|
| 47. |
|
|
| 48. |
- Nielsen, K B, et al.
(författare)
-
Colonisation and molecular diversity of arbuscular mycorrhizal fungi in the aquatic plants Littorella uniflora and Lobelia dortmanna in southern Sweden
- 2004
-
Ingår i: Mycological Research. - 0953-7562. ; 108:6, s. 616-625
-
Tidskriftsartikel (refereegranskat)abstract
- The colonisation intensity and composition of the mycorrhizal community in the aquatic plants Lobelia dortmanna and Littorella uniflora were studied. The mycorrhizal fungi were characterised by fungal specific nested PCR and sequencing using the 5'-end of the LSU rDNA as target. For this, primers for the clade of Acaulospora, the clade including Glomus mosseae and G. intraradices and the clade containing G. etunicatum and G. claroideum were used. The nested PCR products were screened for different sequence types using single stranded conformation polymorphism (SSCP) and representatives for each type were sequenced. A phylogenctic analysis of the sequences showed two phylotypes of Acaulospora, one phylotype within the clade of G. etunicatum/G. claroideum and five within the G. mosseael G. intraradices clade. The colonisation intensity was comparable to that seen in typical grassland vegetation. The neutral lipid fatty acid 16: 1omega5 was seen to be indicative of mycorrhizal colonisation with concentrations up to 35 nmol mg(-1) root DW, which indicates that the fungi are active.
|
|
| 49. |
- Nielsen, Michael B., et al.
(författare)
-
Dynamic Tubular Grid: An Efficient Data Structure and Algorithms for High Resolution
- 2004
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Level set methods [OS88] have proved very successful for interface tracking in many different areas of computational science. However, current level set methods are limited by a poor balance between computational efficiency and storagerequirements. Tree-based methods have relatively slow access times, whereas narrow band schemes lead to very large memory footprints for high resolution interfaces. In this paper we present a level set scheme for which both computational complexity and storage requirements scale with the size of the interface. Our novel level set data structure and algorithms are fast, cache efficient and allow for avery low memory footprint when representing high resolution level sets. We use a time-dependent and interface adapting grid dubbed the .Dynamic Tubular Grid. or DT-Grid. Additionally, it has been optimized for advanced nite difference schemes currently employed in accurate level set computations. As a key feature of the DT-Grid the associated interface propagations are not limited to any computational box and can expand freely. We present several numerical evaluations, including a level set simulation on a grid with an effective resolution of 10243.
|
|
| 50. |
- Nybo, L, et al.
(författare)
-
A spurious correlation - Reply
- 2004
-
Ingår i: JOURNAL OF APPLIED PHYSIOLOGY. - 8750-7587. ; 97:2, s. 793-793
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
