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| 11. |
- Laj, P., et al.
(författare)
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Measuring Atmospheric Composition Change
- 2009
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1873-2844 .- 1352-2310. ; 43:33, s. 5351-5414
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Tidskriftsartikel (refereegranskat)abstract
- Scientific findings from the last decades have clearly highlighted the need for a more comprehensive approach to atmospheric change processes. In fact, observation of atmospheric composition variables has been an important activity of atmospheric research that has developed instrumental tools (advanced analytical techniques) and platforms (instrumented passenger aircrafts, ground-based in-situ and remote sensing stations, earth observation satellite instruments) providing essential information on the composition of the atmosphere. The variability of the atmospheric system and the extreme complexity of the atmospheric cycles for short-lived gaseous and aerosol species have led to the development of complex models to interpret observations, test our theoretical understanding of atmospheric chemistry and predict future atmospheric composition. The validation of numerical models requires accurate information concerning the variability of atmospheric composition for targeted species via comparison with observations and measurements. In this paper, we provide an overview of recent advances in instrumentation and methodologies for measuring atmospheric composition changes from space, aircraft and the surface as well as recent improvements in laboratory techniques that permitted scientific advance in the field of atmospheric chemistry. Emphasis is given to the most promising and innovative technologies that will become operational in the near future to improve knowledge of atmospheric composition. Our current observation capacity, however, is not satisfactory to understand and predict future atmospheric composition changes, in relation to predicted climate warming. Based on the limitation of the current European observing system, we address the major gaps in a second part of the paper to explain why further developments in current observation strategies are still needed to strengthen and optimise an observing system not only capable of responding to the requirements of atmospheric services but also to newly open scientific questions.
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| 13. |
- Bergthorsson, J.T., et al.
(författare)
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BRCA1 and BRCA2 mutation status and cancer family history of Danish women affected with multifocal or bilateral breast cancer at a young age
- 2001
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Ingår i: Journal of Medical Genetics. - : BMJ. - 0022-2593 .- 1468-6244. ; 38:6, s. 361-368
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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.
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| 14. |
- Moore, K. L. F., et al.
(författare)
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Improved survival in myeloma patients-a nationwide registry study of 4,647 patients=75 years treated in Denmark and Sweden
- 2023
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Ingår i: Haematologica. - : Ferrata Storti Foundation (Haematologica). - 0390-6078 .- 1592-8721. ; 108:6, s. 1640-1651
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Tidskriftsartikel (refereegranskat)abstract
- The prevalence of multiple myeloma (MM) is increasing in Nordic countries and the rest of the western world. Patients aged =75 years at diagnosis constitute an increasing proportion of all MM patients, but are underrepresented in randomized clinical trials. There is an urgent need for studies of the characteristics, treatment and outcome in this cohort. We present data from two nationwide population-based registries of all MM patients diagnosed in Denmark from January 1, 2005 until February 18, 2020, and in Sweden from January 1, 2008 until December 31, 2019, including treatment data for patients diagnosed until 2018 (Denmark) and 2019 (Sweden). In total 4,647 patients were =75 years at diagnosis, compared to 7,378 younger patients. Patients =75 years, accounting for approximately 40% of all MM patients, are a distinct cohort with more advanced disease at diagnosis, reflected by higher International Staging System (ISS) stage, and a higher proportion have renal failure and anemia. We found a more gradual introduction of modern medications in the older cohort than in the younger, despite simultaneous changes in guidelines. Compared to the cohorts in randomized controlled trials that guide the treatment of non-transplant eligible patients, we found a higher proportion of patients =75 years and presenting with ISS III in the real-world populations. Nevertheless, response rates and survival are increasing, indicating that modern treatment regimens are effective and well tolerated also in elderly MM patients in real-world populations.
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| 15. |
- Alme, Tomas Nordheim, et al.
(författare)
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Chronic fatigue syndromes: real illnesses that people can recover from
- 2023
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Ingår i: Scandinavian Journal of Primary Health Care. - : TAYLOR & FRANCIS LTD. - 0281-3432 .- 1502-7724. ; 41:4, s. 372-376
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Tidskriftsartikel (refereegranskat)abstract
- The Oslo Chronic Fatigue Consortium consists of researchers and clinicians who question the current narrative that chronic fatigue syndromes, including post-covid conditions, are incurable diseases. Instead, we propose an alternative view, based on research, which offers more hope to patients. Whilst we regard the symptoms of these conditions as real, we propose that they are more likely to reflect the brains response to a range of biological, psychological, and social factors, rather than a specific disease process. Possible causes include persistent activation of the neurobiological stress response, accompanied by associated changes in immunological, hormonal, cognitive and behavioural domains. We further propose that the symptoms are more likely to persist if they are perceived as threatening, and all activities that are perceived to worsen them are avoided. We also question the idea that the best way to cope with the illness is by prolonged rest, social isolation, and sensory deprivation.Instead, we propose that recovery is often possible if patients are helped to adopt a less threatening understanding of their symptoms and are supported in a gradual return to normal activities. Finally, we call for a much more open and constructive dialogue about these conditions. This dialogue should include a wider range of views, including those of patients who have recovered from them.
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| 16. |
- Blimark, Cecilie, et al.
(författare)
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Outcome data from >10 000 multiple myeloma patients in the Danish and Swedish national registries
- 2022
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Ingår i: European Journal of Haematology. - : Wiley. - 0902-4441 .- 1600-0609. ; 108:2, s. 99-108
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Tidskriftsartikel (refereegranskat)abstract
- Objective We describe real-world evidence (RWE) from the nationwide Swedish and Danish registries that provide important information on incidence and outcome in multiple myeloma (MM). Method First line treatment data on more than 10.000 MM patients from Denmark and Sweden between 2005-2018 are presented. Key results from research conducted within the Swedish and Danish myeloma registries are summarized, describing subgroups of patients with comorbidity, myeloma complications, and early relapse. Results We show that national guidelines, generated on results from randomized clinical trials (RCTs) are rapidly implemented and improve overall survival (OS). We find that both the incidence of MM and the median age at diagnosis is higher in national registries compared to results from referral centres, indicating a more complete coverage. This highlights the need of validation of prognostic scoring systems and indices in e.g., SMM and high-risk MM in a real- world-population. We show that these subgroups are unlikely to be captured in RCTs with narrow inclusion and exclusion criteria, that they have worse survival, and are in need of new treatment approaches. Conclusion National registries that include all MM patients are an important source of knowledge on epidemiology, treatment and outcome with implications for the planning of MM care. Despite the introduction of new and better treatments, rapidly implemented in our countries, our registries uncover subgroups of patients that still have inferior outcome. Our RWE can help to identify important research questions to be studied in further clinical trials also in patients currently not included in RCTs.
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| 17. |
- Klausen, Sarah J., et al.
(författare)
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Evaluation of the extraction of bioactive compounds and the saccharification of cellulose as a route for the valorization of spent mushroom substrate
- 2023
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Ingår i: Molecules. - : MDPI. - 1431-5157 .- 1420-3049. ; 28:13
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Tidskriftsartikel (refereegranskat)abstract
- The extraction of bioactive compounds and cellulose saccharification are potential directions for the valorization of spent mushroom substrate (SMS). Therefore, investigating the suitability of different extraction methods for recovering bioactive compounds from SMS and how the extraction affects the enzymatic saccharification is of uppermost relevance. In this work, bioactive compounds were extracted from Pleurotus spp. SMS using four extraction methods. For Soxhlet extraction (SoE), a 40:60 ethanol/water mixture gave the highest extraction efficiency (EE) (69.9–71.1%) among the seven solvent systems assayed. Reflux extraction with 40:60 ethanol/water increased the extraction yield and EE compared to SoE. A shorter reflux time yielded a higher extraction of carbohydrates than SoE, while a longer time was more effective for extracting phenolics. The extracts from 240 min of reflux had comparable antioxidant activity (0.3–0.5 mM GAE) with that achieved for SoE. Ultrasound-assisted extraction (UAE) at 65 °C for 60 min allowed an EE (~82%) higher than that achieved by either reflux for up to 150 min or SoE. Subcritical water extraction (SWE) at 150 °C resulted in the best extraction parameters among all the tested methods. Vanillic acid and chlorogenic acid were the primary phenolic acids identified in the extracts. A good correlation between the concentration of caffeic acid and the antioxidant activity of the extracts was found. Saccharification tests revealed an enhancement of the enzymatic digestibility of SMS cellulose after the extraction of bioactive compounds. The findings of this initial study provide indications on new research directions for maximizing the recovery of bioactive compounds and fermentable sugars from SMS.
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| 18. |
- Nielsen, U., et al.
(författare)
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Removal of APIs and bacteria from hospital wastewater by MBR plus O-3, O-3 + H2O2, PAC or ClO2
- 2013
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Ingår i: Water Science and Technology. - : IWA Publishing. - 0273-1223 .- 1996-9732. ; 67:4, s. 854-862
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study has been to develop technologies that can reduce the content of active pharmaceutical ingredients (APIs) and bacteria from hospital wastewater. The results from the laboratory-and pilot-scale testings showed that efficient removal of the vast majority of APIs could be achieved by a membrane bioreactor (MBR) followed by ozone, ozone + hydrogen peroxide or powdered activated carbon (PAC). Chlorine dioxide (ClO2) was significantly less effective. MBR + PAC (450 mg/l) was the most efficient technology, while the most cost-efficient technology was MBR + ozone (156 mg O-3/l applied over 20 min). With MBR an efficient removal of Escherichia coli and enterococci was measured, and no antibiotic resistant bacteria were detected in the effluent. With MBR + ozone and MBR + PAC also the measured effluent concentrations of APIs (e.g. ciprofloxacin, sulfamethoxazole and sulfamethizole) were below available predicted no-effect concentrations (PNEC) for the marine environment without dilution. Iodinated contrast media were also reduced significantly (80-99% for iohexol, iopromide and ioversol and 40-99% for amidotrizoateacid). A full-scale MBR treatment plant with ozone at a hospital with 900 beds is estimated to require an investment cost of (sic)1.6 mill. and an operating cost of (sic)1/m(3) of treated water.
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| 19. |
- Olsson, Johan, et al.
(författare)
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Baddeleyite U–Pb ages and gechemistry of the 1875–1835 Ma Black Hills Dyke Swarm across north-eastern South Africa : part of a trans-Kalahari Craton back-arc setting?
- 2016
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Ingår i: GFF. - : Informa UK Limited. - 1103-5897 .- 2000-0863. ; 138:1, s. 183-202
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Tidskriftsartikel (refereegranskat)abstract
- Eleven new baddeleyite U–Pb crystallisation ages and associated whole-rock geochemistry on NE–NNE-trending tholeiitic dykes cutting across the north-eastern corner of the Archaean Kaapvaal Craton, the overlying Transvaal basin and the Bushveld and Phalaborwa igneous complexes collectively define a 1875–1835 Ma Black Hills Dyke Swarm (BHDS). Dyke ages do not discriminate between dyke trends or geographic location, but subdivide the BHDS into an older set of four more primitive dykes (MgO = 9.4–6.8 wt.%) and a younger set of seven dykes with more differentiated compositions (MgO = 5.6–4.2 wt.%). Despite being emplaced over a c. 40 Myr period, major element compositions are remarkably consistent with a single inversely modelled bulk fractionating assemblage of 57.5% plagioclase, 29.5% augite and 13.0% olivine. This fractionating assemblage requires an additional assimilation of bulk continental crust (at a low r-value of 0.2) for reversed modelling of parental rare earth elements. Even though this crustal assimilation indicates that primary magmas could potentially have been derived from a spinel-bearing ambient primordial and asthenospheric mantle source, anomalously low Nb and high Pb values for the more primitive older dykes may also have been inherited from a sub-continental lithospheric mantle source. The ages for the BHDS bridge a gap between c. 1889 and 1867 Ma mafic sills and c. 1830 Ma rhyodacitic pyroclasts, interbedded in the top of a ~3 km-thick Sibasa basalt sequence, which combine into a continuous c. 1.89–1.83 Ga igneous province. Similar geochemical signatures are consistent with all sills, volcanic rocks and BHDS feeders collectively belonging to a very voluminous and coherent igneous province, which arguably formed behind active Magondi and Okwa-Kheis arcs, along the western margin of the proto-Kalahari Craton.
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| 20. |
- Olsson, J. R., et al.
(författare)
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U-Pb baddeleyite ages linking major Archean dyke swarms to volcanic-rift forming events in the Kaapvaal craton (South Africa), and a precise age for the Bushveld Complex
- 2010
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Ingår i: Precambrian Research. - : Elsevier BV. - 0301-9268. ; 183:3, s. 490-500
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Tidskriftsartikel (refereegranskat)abstract
- The Archean basement in the northeastern part of the Kaapvaal craton is intruded by a large number of mafic dykes, defining three major dyke swarms, which collectively appear to fan out from the Bushveld Complex. Herein we present U-Pb baddeleyite ages for two of these dyke swarms, the northwest trending Badplaas Dyke Swarm and the east-west trending Rykoppies Dyke Swarm, and infer their correlation with tectonic events in the Kaapvaal craton. We also present a U-Pb baddeleyite age for a noritic phase of the Marginal Zone of the Rustenburg layered Suite (Bushveld Complex). The age of the Badplaas swarm is determined from two dolerites dated at 2965.9 +/- 0.7 Ma and 2967.0 +/- 1.1 Ma. These ages coincide with units of the Nsuze Group lavas (2967-2985 Ma), which constitute the world's oldest preserved rift basin, and suggest that dykes of this swarm are feeders to basaltic units of this group. Similarly, the E-W trending Rykoppies swarm has earlier been interpreted as a potential feeder system to the Bushveld Complex. However, the emplacement ages of six dolerites fall in the range 2.66-2.68 Ga, thus similar to 600 Myr earlier than the intrusion of the Bushveld Complex (herein dated at 2057.7 +/- 1.6 Ma). Rather, these ages coincide with the Allanridge Formation at the uppermost part of the Ventersdorp Supergroup as well as volcanic rocks of the "protobasinal" sequences preserved at the base of the overlying Transvaal Basin. The Rykoppies Dyke Swarm probably marks the initial stages of rifting of the Transvaal Basin and reflects a major shift from a NW-SE to an E-W trending tectonic setting. The origin of the Rykoppies Dyke Swarm can be linked either to prolonged mantle plume activity or to the onset of back-arc extension associated with south-directed subduction of oceanic lithosphere in a compressional setting along the northern margin of the Kaapvaal craton. (C) 2010 Elsevier B.V. All rights reserved.
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| 21. |
- Prakash, A, et al.
(författare)
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Deliverable D6.3 : Trials and experimentation (cycle 3)
- 2022
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Rapport (refereegranskat)abstract
- This deliverable presents the third and final cycle of trials and experimentation activities executed over 5GENESIS facilities. The document is the continuation of deliverables D6.1 and D6.2, in the sense that it captures tests carried out over the evolved infrastructures hosting 5GENESIS facilities following the methodology defined in the previous editions of this deliverable. The tests reported in this document focus on i) the final 5G infrastructure deployments that includes radio and core elements mostly in Stand-Alone (SA) deployment configurations based on commercial and open implementations, and ii) the various use cases/applications, some of them also involving field trials. Most of the tests described herein, especially the generic/lab ones are performed using the Open5GENESIS experimentation suite.
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| 22. |
- Prasetyo, Endry Nugroho, et al.
(författare)
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Polymerization of lignosulfonates by the laccase-HBT (1-hydroxybenzotriazole) system improves dispersibility
- 2010
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Ingår i: Bioresource Technology. - : Elsevier BV. - 0960-8524 .- 1873-2976. ; 101:14, s. 5054-5062
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Tidskriftsartikel (refereegranskat)abstract
- The ability of laccases from Trametes villosa (TvL), Myceliophthora thermophila (MtL), Trametes hirsuta (ThL) and Bacillus subtilis (BsL) to improve the dispersion properties of calcium lignosulfonates 398 in the presence of HBT as a mediator was investigated. Size exclusion chromatography showed an extensive increase in molecular weight of the samples incubated with TvL and ThL by 107% and 572% from 28400 Da after 17 h of incubation, respectively. Interestingly, FTIR spectroscopy. C-13 NMR and Py-GC/MS analysis of the treated samples suggested no substantial changes in the aromatic signal of the lignosulfonates, a good indication of the ability of TvL/ThL-HBT systems to limit their effect on functional groups without degrading the lignin backbone. Further, the enzymatic treatments led to a general increase in the dispersion properties, indeed a welcome development for its application in polymer blends. (C) 2010 Elsevier Ltd. All rights reserved.
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| 23. |
- Shaw, Cliff S. J., et al.
(författare)
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Kinetics of dissolution of sapphire in melts in the CaO-Al2O3-SiO2 system
- 2018
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Ingår i: Geochimica et Cosmochimica Acta. - : Elsevier. - 0016-7037 .- 1872-9533. ; 229, s. 129-146
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Tidskriftsartikel (refereegranskat)abstract
- The dissolution rate of sapphire in melts in the CAS system of varying silica activity, viscosity and degree of alumina saturation has been determined at 1600 degrees C and 1.5 GPa. After an initiation period of up to 1800 s, dissolution is controlled by diffusion of cations through the boundary layer adjacent to the dissolving sapphire. The dissolution rate decreases with increasing silica activity, viscosity and molar Al2O3/CaO. The calculated diffusion matrix for each solvent melt shows that CAS 1 and 9 which have molar Al2O3/CaO of 0.33 and 0.6 and dissolution rate constants of 0.65 x 10(-6) and 0.59 x 10(-6) m/s(0.5) have similar directions and magnitudes of diffusive coupling: DCaO-Al2O3 and DAl2O3-CaO are both negative are approximately equal. The solvent with the fastest dissolution rate: CAS 4, which has a rate constant of 1.5 x 10(-6) m/s(0.5) and Al2O3/CaO of 0.31 has positive DCaO-Al2O3 and negative DAl2O3-CaO and the absolute values vary by a factor of 4. Although many studies show that aluminium is added to the melts via the reaction: Si4+ = Al3+ + 0.5 Ca2+ the compositional profiles show that this reaction is not the only one involved in accommodating the aluminium added during sapphire dissolution. Rather, aluminium is incorporated as both tetrahedrally coordinated Al charge balanced by Ca and as aluminium not charge balanced by Ca (termed Al-xs). This reaction: Al-IV-Ca = Al-xs thorn Ca-NBO where Ca-NBO is a non-bridging oxygen associated with calcium, may involve the formation of aluminium triclusters. The shape of the compositional profiles and oxide-oxide composition paths is controlled by the aluminium addition reaction. When Al-xs exceeds 2%, CaO diffusion becomes increasingly anomalous and since the bond strength of Al-xs correlates with CaO/CaO + Al2O3, the presence of more than 2% Al-xs leads to significantly slower dissolution than when Al-xs is absent or at low concentration. Thus, dissolution is controlled by diffusion of cations through the boundary layer, but this diffusion is itself controlled by the structural modifications required by the addition of new components to the melt. Comparison of quartz dissolution rates in similar melts shows that dissolution is much faster for quartz than for sapphire and that dissolution rates show the same correlation with silica activity and viscosity. We suggest that diffusive fluxes are related to changes in melt structure and the nature of the reaction that incorporates the added component. For the slow eigendirection, SiO2 addition occurs by a single reaction whereas Al2O3 addition requires a more complex two part reaction in which Al is accommodated by charge balance with Ca until Al is in excess of that which can be charge balanced. The Al-xs incorporation reaction, is slower than the Si incorporation reaction which inhibits sapphire dissolution relative to quartz in melts of the same composition.
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| 25. |
- Ternov, K. K., et al.
(författare)
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Quality of life in men with metastatic castration-resistant prostate cancer treated with enzalutamide or abiraterone: a systematic review and meta-analysis
- 2021
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Ingår i: Prostate Cancer and Prostatic Diseases. - : Springer Science and Business Media LLC. - 1365-7852 .- 1476-5608. ; 24:4, s. 948-961
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Forskningsöversikt (refereegranskat)abstract
- Background Enzalutamide and abiraterone acetate plus prednisone (AAP) have similar efficacy in metastatic castration-resistant prostate cancer (mCRPC), but different mechanisms of action. The aim was to compare patient-reported health-related quality of life (HRQoL) in men treated with enzalutamide vs AAP for mCRPC. Methods We systematically reviewed the literature in June 2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Patient-reported outcomes (PROs) until the last follow-up were summarised in a narrative synthesis. Short-term changes (12 weeks) in HRQoL, measured by the Functional Assessment of Cancer Therapy-Prostate total score (FACT-P), were compared between treatment groups and were analysed for enzalutamide and AAP in separate meta-analyses. Higher FACT-P scores indicate better HRQoL. Results Eight studies were included in the systematic review, four of which were randomised clinical trials (RCTs) eligible for the meta-analyses. The meta-analyses showed mean within-subject FACT-P changes from baseline to week 12 of -1.3 points (95% confidence interval [CI] -2.7; 0.1) for enzalutamide and 4.7 points (95% CI -0.1; 9.6) for AAP. One RCT and three non-randomised studies directly compared enzalutamide with AAP. The RCT showed better short-term HRQoL for AAP (6.8 FACT-P-points, 95% CI 1.7; 11.8) and better long-term HRQoL for AAP in men >= 75 years (7.35 FACT-P-points, 95% CI 2.59; 12.11). The non-randomised studies showed no difference in long-term HRQoL but had all a serious risk of bias. Limitations of the included studies include that the PRO in the included trials were inconsistently reported and that only one study defined the HRQoL measures in their published protocol. Conclusions AAP seems to be associated with better short-term HRQoL than enzalutamide. This difference was not apparent at longer follow-up, but the long-term studies had serious risks of bias.
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| 26. |
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| 27. |
- Wabo, H., et al.
(författare)
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Paleomagnetism and chronology of B-1 marginal sills of the Bushveld Complex from the eastern Kaapvaal Craton, South Africa
- 2016
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Ingår i: GFF. - : Informa UK Limited. - 1103-5897 .- 2000-0863. ; 138:1, s. 133-151
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Tidskriftsartikel (refereegranskat)abstract
- The Rustenburg Layered Suite (RLS) of the Bushveld Complex in South Africa is the largest mafic–ultramafic-layered complex on Earth. The RLS is associated with marginal sills that penetrate into the ~2.2 billion-year-old sedimentary strata of the Pretoria Group. These sills are in contact and share some geochemical similarities with different zones of RLS and are classified in terms of chemical composition, which suggests their derivation from distinct parental magma compositions (so-called B-1, B-2 and B-3 parental magmas). Existing paleomagnetic constraints for the Bushveld Complex originate from the upper Critical to Upper zones of the RLS, which are associated with B-2 and B-3 marginal sills. Geochemically, verified B-1 marginal intrusions are here used as a proxy for constraining the paleomagnetism and chronology of the Lower and lower Critical zones of the RLS. We identified a dual-polarity magnetic component with a paleopole (Latitude = 13.1°N, Longitude = 44.0°E, A95 = 14.3, N = 7) that is very similar to the established Bushveld Complex poles. We further report 2058.4 ± 1.3 Ma and 2058.1 ± 6 Ma U–Pb baddeleyite ages from B-1 sills that record opposite magnetic polarities. The ca. 2058 Ma ages are older than the 2054.89 ± 0.37 Ma age recently reported from throughout the RLS, but near identical to a previously reported ages of the Marginal Zone and from the upper Critical Zone. The ages could be interpreted as distinct pulses of magma emplacement separated in time by up to 4 million years (i.e., B-1 type magma pulse around ca. 2058 Ma and the B-2 and B-3 types magma pulses following closely on each other around ca. 2054 Ma), but is unlikely when petrological models are considered.
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