| 1. |
- Raiteri, C. M., et al.
(författare)
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WEBT and XMM-Newton observations of 3C 454.3 during the post-outburst phase - Detection of the little and big blue bumps
- 2007
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 473:3, s. 819-827
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Tidskriftsartikel (refereegranskat)abstract
- Context. The quasar-type blazar 3C 454.3 was observed to undergo an unprecedented optical outburst in spring 2005, affecting the source brightness from the near-IR to the X-ray frequencies. This was first followed by a millimetric and then by a radio outburst, which peaked in February 2006. Aims. In this paper we report on follow-up observations to study the multiwavelength emission in the post-outburst phase. Methods. Radio, near-infrared, and optical monitoring was performed by the Whole Earth Blazar Telescope (WEBT) collaboration in the 2006-2007 observing season. XMM-Newton observations on July 2-3 and December 18-19, 2006 added information on the X-ray and UV states of the source. Results. The source was in a faint state. The radio flux at the higher frequencies showed a fast decreasing trend, which represents the tail of the big radio outburst. It was followed by a quiescent state, common at all radio frequencies. In contrast, moderate activity characterized the near-IR and optical light curves, with a progressive increase of the variability amplitude with increasing wavelength. We ascribe this redder-when-brighter behaviour to the presence of a ""little blue bump"" due to line emission from the broad line region, which is clearly visible in the source spectral energy distribution (SED) during faint states. Moreover, the data from the XMM- Newton Optical Monitor reveal a rise of the SED in the ultraviolet, suggesting the existence of a "" big blue bump"" due to thermal emission from the accretion disc. The X-ray spectra are well fitted with a power- law model with photoelectric absorption, possibly larger than the Galactic one. However, the comparison with previous X-ray observations would imply that the amount of absorbing matter is variable. Alternatively, the intrinsic X-ray spectrum presents a curvature, which may depend on the X-ray brightness. In this case, two scenarios are possible. i) There is no extra absorption, and the X-ray spectrum hardens at low energies, the hardening being more evident in bright states; ii) there is a constant amount of extra absorption, likely in the quasar environment, and the X-ray spectrum softens at low energies, at least in faint X-ray states. This softening might be the result of a flux contribution by the high-frequency tail of the big blue bump.
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| 2. |
- Nordin, Jakob, et al.
(författare)
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EVIDENCE FOR A CORRELATION BETWEEN THE Si II lambda 4000 WIDTH AND TYPE Ia SUPERNOVA COLOR
- 2011
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 734:1, s. 42-
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Tidskriftsartikel (refereegranskat)abstract
- We study the pseudo-equivalent width of the Si II lambda 4000 feature of Type Ia supernovae (SNe Ia) in the redshift range 0.0024 <= z <= 0.634. We find that this spectral indicator correlates with the light curve color excess (SALT2c) as well as previously defined spectroscopic subclasses (Branch types) and the evolution of the Si II lambda 6150 velocity, i.e., the so-called velocity gradient. Based on our study of 55 objects from different surveys, we find indications that the Si II lambda 4000 spectral indicator could provide important information to improve cosmological distance measurements with SNe Ia.
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| 3. |
- Nordin, Jakob, et al.
(författare)
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Evidence for a correlation between the SiII λ4000 width and Type Ia supernova color
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357.
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Tidskriftsartikel (refereegranskat)abstract
- We study the pseudo equivalent width of the SiII λ4000 feature of Type Iasupernovae (SNe Ia) in the redshift range 0.0024 ≤z ≤0.634. We find that this spectral indicator correlateswith the light curve color excess SALT2 c as well as previouslydefined spectroscopic subclasses (Branch types) and theevolution of the SiII λ6150 velocity, i.e., the so called velocitygradient. Based on our study of 55 objects from different surveys, we find indications that the SiII λ4000 spectral indicatorcould provide important information to improve cosmological distancemeasurements with SNe Ia.
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| 4. |
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| 5. |
- Elliott, D. C., et al.
(författare)
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Technoeconomic assessment of direct biomass liquefaction to transportation fuels
- 1990
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Ingår i: Biomass. - 0144-4565. ; 22:1-4, s. 251-269
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Tidskriftsartikel (refereegranskat)abstract
- This paper discusses the results of a technoeconomic assessment of direct biomass liquefaction processes converting wood to gasoline and diesel fuels. The study was carried out by the Working Group of the International Energy Agency Direct Biomass Liquefaction Activity, in which Canada, Finland, Sweden, and the US participated. The processes chosen for detailed analysis were Atmospheric Flash Pyrolysis (AFP) and Liquefaction In Pressurized Solvent (LIPS). The assessment covered three steps for each process from feed to final product: 1. 1. primary liquefaction to a crude oil product, 2. 2. catalytic hydrotreating to upgrade the crude product to a deoxygenated product oil, 3. 3. refining the deoxygenated product to gasoline and diesel fuel. Present technology cases and potential future technology cases were evaluated. A consistent analytical basis was used throughout to allow comparison of the processes. This assessment shows that AFP is more economical than LIPS both for the production of boiler fuel oil as the primary liquefaction product and for the production of gasoline and diesel fuel products. The potential for future cost reduction through research and development is also clearly demonstrated.
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| 6. |
- Enerbäck, Hanna, et al.
(författare)
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Effect of a mouth rinse and a high-fluoride toothpaste on caries incidence in orthodontic patients: A randomized controlled trial
- 2022
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Ingår i: American Journal of Orthodontics and Dentofacial Orthopedics. - : Elsevier BV. - 0889-5406. ; 162:1
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The objective was to evaluate the effect of a fluoride mouth rinse and a high-fluoride toothpaste on caries incidence in patients undergoing orthodontic treatment with fixed appliances. Methods: In this 3-armed, parallel-group, randomized controlled trial, patients referred to the Specialist Clinic of Orthodontics, Mölndal, Sweden, were randomly allocated to 1 of the 3 groups. (1) Fluoride mouth rinse (FMR) group: 0.2 % sodium fluoride (NaF) mouth rinse plus 1450 ppm fluoride (F) toothpaste; (2) High-fluoride tootpaste (HFT) group: 5000 ppm F toothpaste; and (3) Control (CTR) group: 1450 ppm F toothpaste. The generation of a randomization sequence was performed in blocks of 30. Inclusion criteria included patients scheduled for treatment with fixed appliances in the maxillary and mandibular arch aged 12-20 years. The primary outcome variable was the change in Decayed Initial Filled Surfaces (ΔDiFS) based on radiographs taken before and after the treatment. For statistical comparisons between groups, the Kruskal–Wallis test were used for continuous variables, whereas the Mann-Whitney U-test was used for pairwise group comparisons. Furthermore, the risk ratio (RR) and 95% confidence interval (CI) based on clinically relevant cutoffs (DiFS ≥2) were calculated to compare the increase of caries during orthodontic treatment between 2 groups. The Cochran-Mantel-Haenszel method was used to adjust RR for baseline values. Blinding was employed during the caries registration and the data analysis. Results: In total, 270 participants were randomized, with 15 patients dropping out, such that 255 patients were included in the statistical analyses. Recruitment was from October 2010 to December 2012. An increase in DiFS (≥1 DiFS) during treatment was observed in 48.3% of the FMR group, 42.0% of the HFT group, and 35.6% of the CTR group. There was no significant difference between the groups regarding increased DiFS (P = 0.17). The risk of increase in DiFS ≥2 during orthodontic treatment was 31.0% in the FMR group, 25.9% in the HFT group, and 18.4% in the CTR group. The RR for an increase of ≥2 DiFS during orthodontic treatment was 1.38 (95% CI, 0.81-2.34; P = 0.23) for FMR vs CTR, 1.21 (95% CI, 0.70-2.10; P = 0.51) for HFT vs CTR, and 0.93 (95% CI, 0.57-1.49; P = 0.76) for HFT vs FMR. Conclusions: In patients who demonstrate a low prevalence of caries and are undergoing orthodontic treatment, daily use of high-fluoride toothpaste or fluoride mouth rinse in combination with regular toothpaste does not appear to significantly alter the caries incidence compared with the use of regular toothpaste. Trial Registration: The trial was registered in the FoU i Sverige research database (http://www.fou.nu/is/sverige), with registration no. 236251. Protocol: The protocol was not published before trial commencement. Funding: Local Research and Development Board for Gothenburg and South Bohuslän (grant no. 768531); and The Swedish Patent Revenue Fund (grant number EKF-780/19).
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| 7. |
- Enerbäck, Hanna, et al.
(författare)
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Effects of orthodontic treatment and different fluoride regimens on numbers of cariogenic bacteria and caries risk: a randomized controlled trial
- 2019
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Ingår i: European journal of orthodontics. - : Oxford University Press (OUP). - 1460-2210 .- 0141-5387. ; 41:1, s. 59-66
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Tidskriftsartikel (refereegranskat)abstract
- Background: Caries is an undesirable side-effect of treatment with fixed orthodontic appliances. Therefore, it is crucial to understand how orthodontic treatment and different fluoride regimens affect caries risk and individual risk factors. Objective: To evaluate the effects of orthodontic treatment and different fluoride regimens on caries risk and caries risk factors, including cariogenic bacteria. Trial design: Three-armed, parallel group, randomized, controlled trial. Methods: Patients referred to the Specialist Clinic of Orthodontics, Mölndal Hospital, Sweden, were distributed randomly into the following groups: group I (Control group), 1450 ppm fluoride (F) toothpaste; group II, 1450 ppm F toothpaste plus 0.2 per cent sodium fluoride (NaF) mouth rinse; and group III, 5000 ppm F toothpaste. The inclusion criteria were: age 12-20 years; and bimaxillary treatment with fixed appliances. The primary outcome variables were: caries risk; and the numbers of cariogenic bacteria. Radiographs were taken before treatment to determine the caries status. Data were collected before treatment and after 1 year with a fixed appliance. The variables were compiled into a Cariogram to assess the caries risk. Comparisons were made over time within and between the groups. The generation of randomization sequence was performed in blocks of 30. Blinding was employed during the data analysis and the caries registration. Recruitment: The clinical study duration was from October 2010 to December 2012. Results: Overall, 270 patients were randomized, of which 15 were excluded from the study. Therefore, 255 patients were included in the analyses. The caries risk increased significantly during orthodontic treatment in group I (P < 0.0001), whereas groups II and III had unchanged caries risks. All the groups showed statistically significant increases in the numbers of cariogenic bacteria. Harms: No harms were reported during the trial. Conclusions: To avoid an increased risk of caries during orthodontic treatment, everyday use of high-fluoride toothpaste (5000 ppm F) or mouth rinse (0.2% NaF) in combination with ordinary toothpaste is recommended. Registration: The trial was not registered.
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| 8. |
- Kockum, Ingrid, et al.
(författare)
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Genetic and immunological findings in patients with newly diagnosed insulin-dependent diabetes mellitus
- 1996
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Ingår i: Hormone and Metabolic Research. - : Georg Thieme Verlag KG. - 0018-5043 .- 1439-4286. ; 28:7, s. 344-347
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Tidskriftsartikel (refereegranskat)abstract
- Two large population-based case-control studies are reviewed. The aim is to determine the effects of HLA, other genetic factors and immune markers (ICA, IAA and GAD65Ab) on the age at onset of insulin-dependent diabetes mellitus (IDDM) in 0-34 year olds. The primary HLA risk gene sequence for IDDM was difficult to identify because of the low recombination frequency within the HLA region. The frequency of the DR3-DQA1 * 0501-DQB1 * 0201 haplotype and the DR3-DQA1 * 0501 DQB1 * 0201 (DQ2)/DR4-DQA1 * 0301-DQB1 * 0302 (DQ8) genotype were higher among patients diagnosed before the age of 10 compared with those diagnosed after the age of 30. The negatively associated haplotype, DR15-DQA1 * 0102-DQB1 * 0602 was absent before the age of 10, but the frequency increased with increasing age at onset. The IDDM2 gene representing the variable number of tandem repeat (VNTR) sequences and 5' of the insulin gene on chromosome 11 were associated with IDDM since homozygous short VNTR was positive but not homozygous, and heterozygous long VNTR was negatively associated with the disease. The diagnostic sensitivity and specificity of GAD65 (GA65Ab) and insulin (IAA) autoantibodies varied with the age at onset and gender. GAD65Ab had the highest sensitivity (> 80%) in patients older than 20 years of age with no difference in gender. The lowest sensitivity (54%) was in 0-10 year old boys, while age did not affect the sensitivity in girls. In contrast, the sensitivity of IAA was highest (46%) before the age of 15 but decreased thereafter as did the sensitivity for ICA. Classification of patients who develop IDDM above 20-25 years of age was inadequate since many patients classified with NIDDM either had GAD65Ab or ICA or developed these antibodies after 1-2 years of NIDDM. We conclude that not only age but also gender affects the risk for IDDM associated with HLA, other IDDM genes as well as commonly used immunological markers for IDDM.
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| 9. |
- Moro, Carlos Fernandez, et al.
(författare)
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An idiosyncratic zonated stroma encapsulates desmoplastic liver metastases and originates from injured liver
- 2023
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- A perimetastatic capsule is a strong positive prognostic factor in liver metastases, but its origin remains unclear. Here, we systematically quantify the capsule's extent and cellular composition in 263 patients with colorectal cancer liver metastases to investigate its clinical significance and origin. We show that survival improves proportionally with increasing encapsulation and decreasing tumor-hepatocyte contact. Immunostaining reveals the gradual zonation of the capsule, transitioning from benign-like NGFR(high) stroma at the liver edge to FAP(high) stroma towards the tumor. Encapsulation correlates with decreased tumor viability and preoperative chemotherapy. In mice, chemotherapy and tumor cell ablation induce capsule formation. Our results suggest that encapsulation develops where tumor invasion into the liver plates stalls, representing a reparative process rather than tumor-induced desmoplasia. We propose a model of metastases growth, where the efficient tumor colonization of the liver parenchyma and a reparative liver injury reaction are opposing determinants of metastasis aggressiveness.
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| 10. |
- Sako, Masao, et al.
(författare)
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The Data Release of the Sloan Digital Sky Survey-II Supernova Survey
- 2018
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Ingår i: Publications of the Astronomical Society of the Pacific. - : IOP Publishing. - 0004-6280 .- 1538-3873. ; 130:988
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes the data release of the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey conducted between 2005 and 2007. Light curves, spectra, classifications, and ancillary data are presented for 10,258 variable and transient sources discovered through repeat ugriz imaging of SDSS Stripe 82, a 300 deg(2) area along the celestial equator. This data release is comprised of all transient sources brighter than r similar or equal to 22.5 mag with no history of variability prior to 2004. Dedicated spectroscopic observations were performed on a subset of 889 transients, as well as spectra for thousands of transient host galaxies using the SDSS-III BOSS spectrographs. Photometric classifications are provided for the candidates with good multi-color light curves that were not observed spectroscopically, using host galaxy redshift information when available. From these observations, 4607 transients are either spectroscopically confirmed, or likely to be, supernovae, making this the largest sample of supernova candidates ever compiled. We present a new method for SN host-galaxy identification and derive host-galaxy properties including stellar masses, star formation rates, and the average stellar population ages from our SDSS multi-band photometry. We derive SALT2 distance moduli for a total of 1364 SN. Ia with spectroscopic redshifts as well as photometric redshifts for a further 624 purely photometric SN. Ia candidates. Using the spectroscopically confirmed subset of the three-year SDSS-II SN. Ia sample and assuming a flat.CDM cosmology, we determine Omega(M) = 0.315 +/- 0.093 (statistical error only) and detect a non-zero cosmological constant at 5.7 sigma.
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