| 1. |
- Lundgren, Markus, et al.
(författare)
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Analgesic antipyretic use among young children in the TEDDY study : No association with islet autoimmunity
- 2017
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Ingår i: BMC Pediatrics. - : Springer Science and Business Media LLC. - 1471-2431. ; 17:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The use of analgesic antipyretics (ANAP) in children have long been a matter of controversy. Data on their practical use on an individual level has, however, been scarce. There are indications of possible effects on glucose homeostasis and immune function related to the use of ANAP. The aim of this study was to analyze patterns of analgesic antipyretic use across the clinical centers of The Environmental Determinants of Diabetes in the Young (TEDDY) prospective cohort study and test if ANAP use was a risk factor for islet autoimmunity. Methods: Data were collected for 8542 children in the first 2.5 years of life. Incidence was analyzed using logistic regression with country and first child status as independent variables. Holm's procedure was used to adjust for multiplicity of intercountry comparisons. Time to autoantibody seroconversion was analyzed using a Cox proportional hazards model with cumulative analgesic use as primary time dependent covariate of interest. For each categorization, a generalized estimating equation (GEE) approach was used. Results: Higher prevalence of ANAP use was found in the U.S. (95.7%) and Sweden (94.8%) compared to Finland (78.1%) and Germany (80.2%). First-born children were more commonly given acetaminophen (OR 1.26; 95% CI 1.07, 1.49; p = 0.007) but less commonly Non-Steroidal Anti-inflammatory Drugs (NSAID) (OR 0.86; 95% CI 0.78, 0.95; p = 0.002). Acetaminophen and NSAID use in the absence of fever and infection was more prevalent in the U.S. (40.4%; 26.3% of doses) compared to Sweden, Finland and Germany (p < 0.001). Acetaminophen or NSAID use before age 2.5 years did not predict development of islet autoimmunity by age 6 years (HR 1.02, 95% CI 0.99-1.09; p = 0.27). In a sub-analysis, acetaminophen use in children with fever weakly predicted development of islet autoimmunity by age 3 years (HR 1.05; 95% CI 1.01-1.09; p = 0.024). Conclusions: ANAP use in young children is not a risk factor for seroconversion by age 6 years. Use of ANAP is widespread in young children, and significantly higher in the U.S. compared to other study sites, where use is common also in absence of fever and infection.
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| 2. |
- Andersen, Paul Krüger, et al.
(författare)
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Response to the Proposal for a Directive on Corporate Sustainability Due Diligence by Nordic and Baltic Company Law Scholars
- 2022
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- On February 23, 2022, The EU Commission published its Proposal for a Directive of the European Parliament and of the Council on Corporate Sustainability Due Diligence and amending Directive (EU) 2019/1937 (“CSDDD” or “the Proposal”). The purpose of the Proposal, to further the “Union’s transition to a climate-neutral and green economy in line with the European Green Deal and in delivering on the UN Sustainable Development Goals”, is of great importance, and the Commission’s initiative is therefore commendable. However, it is our firm opinion that the Proposal should not be enacted in its present form, and that if it were to be, it would not only damage European businesses but also run the risk of having an adverse effect on both the transition to a climate-neutral economy as well as the goal of delivering on the UN Sustainable Development Goals. This is to a large extent because many of the Proposal’s provisions are excessive, unfounded and disproportionate and as such in violation of the fundamental principles of subsidiarity and proportionality safeguarded by Art. 5 TEU as well as having a questionable basis in Art. 50 TFEU. Furthermore and in regard of procedure, we find that the presentation of the Proposal by the Commission represents a disregard for the principles of better regulation that should not pass unnoticed and must be observed in the future to maintain trust in the legislative process of the Union.In this response to the consultation, we have presented an analysis of the key issues of the Proposal from a corporate governance perspective. We have divided the response into two parts: one on the pure corporate governance parts of the Proposal (article 15, 25 and 26) and one of the due diligence parts of the Proposal. With regards to the corporate governance parts of the Proposal, our conclusion is that they, by and large, should not be included in the proposed directive at all. Including them would in several ways be in breach of the EU principles on subsidiarity and proportionality, but perhaps more importantly, they are not only unsubstantiated by available empirical evidence on corporate behaviour, but also refuted by what we know. There is also good reason to believe that the proposed rules on director’s duties and environmental remuneration would risk decreasing the effectiveness of the stock markets within the EU contrary to the goal of a Capital Market Union, which also risk slowing down the necessary transition to a green economy and the goals of the EU Green Deal. The regulation necessary for the Capital Market Union and the EU Green Deal should complement each other, not collide as would be the outcome if the Proposal is adopted in its present form.With regards to the due diligence parts of the Proposal, our criticism is limited to corporate governance aspects and far less fundamental. We primarily believe that grounds for harmonisation needs further consideration in the present very challenging times, that Article 22 on Civil Liability might in several ways be counter-productive to the goals of the Proposal, that the effects on SMEs as well as for the financial companies included covered by the Proposal warrants further analysis, that the choice to focus the Proposal on individual companies instead of company groups needs to be reviewed, and that a risk based approach should be taken rather than an approach were companies are unable to focus their efforts to where they can be most effective. Overall, these issues can be worked out, but if they are not, then the proposed directive would not only have a severe adverse impact on EU companies and possibly capital markets, but might actually hinder EU companies from acting in the way that the Proposal aims for them to do.This joint response to the public consultation is made by a group of Nordic and Baltic company law scholars who, although we may not agree on every detail, do share the main arguments and grave concerns expressed here.
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| 3. |
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| 4. |
- Bensing, Sophie, et al.
(författare)
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Increased death risk and altered cancer incidence pattern in patients with isolated or combined autoimmune primary adrenocortical insufficiency
- 2008
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Ingår i: Clinical Endocrinology. - : Wiley. - 0300-0664 .- 1365-2265. ; 69:5, s. 697-704
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Primary adrenocortical insufficiency is mostly caused by an autoimmune destruction of the adrenal cortex. The disease may appear isolated or as a part of an autoimmune polyendocrine syndrome (APS). APS1 is a rare hereditary disorder with a broad spectrum of clinical manifestations. In APS2, primary adrenocortical insufficiency is often combined with autoimmune thyroid disease and/or type 1 diabetes. We analysed mortality and cancer incidence in primary adrenocortical insufficiency patients during 40 years. Data were compared with the general Swedish population. DESIGN AND PATIENTS: A population based cohort study including all patients with autoimmune primary adrenocortical insufficiency (3299) admitted to Swedish hospitals 1964-2004. MEASUREMENTS: Mortality risk was calculated as the standardized mortality ratio (SMR) and cancer incidence as the standardized incidence ratio (SIR). RESULTS: A more than 2-fold increased mortality risk was observed in both women (SMR 2.9, 95% CI 2.7-3.0) and men (SMR 2.5, 95% CI 2.3-2.7). Highest risks were observed in patients diagnosed in childhood. SMR was higher in APS1 patients (SMR 4.6, 95% CI 3.5-6.0) compared with patients with APS2 (SMR 2.1, 95% CI 1.9-2.4). Cancer incidence was increased (SIR 1.3, 95% CI 1.2-1.5). When tumours observed during the first year of follow-up were excluded, only the cancer risk among APS1 patients remained increased. Cause-specific cancer incidence analysis revealed significantly higher incidences of oral cancer, nonmelanoma skin cancer, and male genital system cancer among patients. Breast cancer incidence was lower than in the general population. CONCLUSIONS: Our study shows a reduced life expectancy and altered cancer incidence pattern in patients with autoimmune primary adrenocortical insufficiency.
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| 5. |
- Björkholm, Magnus, et al.
(författare)
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Success Story of Targeted Therapy in Chronic Myeloid Leukemia : A Population-Based Study of Patients Diagnosed in Sweden From 1973 to 2008
- 2011
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Ingår i: Journal of Clinical Oncology. - 0732-183X .- 1527-7755. ; 29:18, s. 2514-2520
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Chronic myeloid leukemia (CML) management changed dramatically with the development of imatinib mesylate (IM), the first tyrosine kinase inhibitor targeting the BCR-ABL1 oncoprotein. In Sweden, the drug was approved in November 2001. We report relative survival (RS) of patients with CML diagnosed during a 36-year period. Patients and Methods Using data from the population-based Swedish Cancer Registry and population life tables, we estimated RS for all patients diagnosed with CML from 1973 to 2008 (n = 3,173; 1,796 males and 1,377 females; median age, 62 years). Patients were categorized into five age groups and five calendar periods, the last being 2001 to 2008. Information on use of upfront IM was collected from the Swedish CML registry. Results Relative survival improved with each calendar period, with the greatest improvement between 1994-2000 and 2001-2008. Five-year cumulative relative survival ratios (95% CIs) were 0.21 (0.17 to 0.24) for patients diagnosed 1973-1979, 0.54 (0.50 to 0.58) for 1994-2000, and 0.80 (0.75 to 0.83) for 2001-2008. This improvement was confined to patients younger than 79 years of age. Five-year RSRs for patients diagnosed from 2001 to 2008 were 0.91 (95% CI, 0.85 to 0.94) and 0.25 (95% CI, 0.10 to 0.47) for patients younger than 50 and older than 79 years, respectively. Men had inferior outcome. Upfront overall use of IM increased from 40% (2002) to 84% (2006). Only 18% of patients older than 80 years of age received IM as first-line therapy. Conclusion This large population-based study shows a major improvement in outcome of patients with CML up to 79 years of age diagnosed from 2001 to 2008, mainly caused by an increasing use of IM. The elderly still have poorer outcome, partly because of a limited use of IM.
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| 6. |
- Christensson, Anders, et al.
(författare)
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Association of cancer with moderately impaired renal function at baseline in a large, representative, population-based cohort followed for up to 30 years.
- 2013
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 133:6, s. 1452-1458
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Tidskriftsartikel (refereegranskat)abstract
- Patients with chronic renal failure show a greater incidence of malignancies. We evaluated whether moderately impaired renal function at baseline influenced risk of all cancers during long-term follow in young persons. Our cohort included 33,346 subjects, aged 26-61 years at baseline, in a representative, population-based study enrolling subjects from 1974 to 1992. Median follow-up time was 28 years. Plasma creatinine was analysed as a single measure at baseline. Incident cases of cancer were identified from the Swedish Cancer Registry. We studied 24,552 subjects from the cohort. To account for the unique sampling design, participants were divided by sex and age at baseline into 1,132 older men (age 60), 14,254 younger men (age 40-52), 7,498 older women (age 47-57) and 1,688 younger women (age 35-43). Glomerular filtration rate (GFR) was estimated using the CKD-EPI formula. Patients were classified as having either normal to mildly impaired kidney function (eGFR≥60 mL/min/1.73m(2) ), or moderate kidney dysfunction (eGFR<60 mL/min/1.73m(2) ). We calculated the risk of all cancers using competing risks regression. Overall, 6,595 participants were diagnosed with cancer, and 854 subjects (3.5%) had moderately impaired renal dysfunction at baseline. There was a significant association between moderately decreased GFR and subsequent risk of kidney cancer in younger men (hazard ratio, 3.38; 95% CI, 1.48 to 7.71; P=0.004). However, we found no association with overall long-term cancer risk. Our confirmation of an association between moderately impaired renal function and risk of kidney cancer in younger men requires further exploration of high-risk groups and biological mechanisms. © 2013 Wiley Periodicals, Inc.
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| 7. |
- Dou, Diana R., et al.
(författare)
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Xist ribonucleoproteins promote female sex-biased autoimmunity
- 2024
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Ingår i: Cell. - : Elsevier BV. - 0092-8674 .- 1097-4172. ; 187:3, s. 16-733
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Tidskriftsartikel (refereegranskat)abstract
- Autoimmune diseases disproportionately affect females more than males. The XX sex chromosome complement is strongly associated with susceptibility to autoimmunity. Xist long non-coding RNA (lncRNA) is expressed only in females to randomly inactivate one of the two X chromosomes to achieve gene dosage compensation. Here, we show that the Xist ribonucleoprotein (RNP) complex comprising numerous autoantigenic components is an important driver of sex-biased autoimmunity. Inducible transgenic expression of a non-silencing form of Xist in male mice introduced Xist RNP complexes and sufficed to produce autoantibodies. Male SJL/J mice expressing transgenic Xist developed more severe multi-organ pathology in a pristane-induced lupus model than wild-type males. Xist expression in males reprogrammed T and B cell populations and chromatin states to more resemble wild-type females. Human patients with autoimmune diseases displayed significant autoantibodies to multiple components of XIST RNP. Thus, a sex-specific lncRNA scaffolds ubiquitous RNP components to drive sex-biased immunity.
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| 8. |
- Elf, Johan, et al.
(författare)
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Problems of high dimension in molecular biology
- 2003
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Ingår i: Proc. 19th GAMM Seminar Leipzig on High-dimensional problems. - Leipzig, Germany : Max Planck Institute for Mathematics in the Sciences. ; , s. 21-30
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Konferensbidrag (refereegranskat)
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| 9. |
- Elf, Johan, et al.
(författare)
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Problems of High Dimension in Molecular Biology
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The deterministic reaction rate equations are not an accurate description of many systems in molecular biology where the number of molecules of each species often is small. The master equation of chemical reactions is a more accurate stochastic description suitable for small molecular numbers. A computational difficulty is the high dimensionality of the equation. We describe how it can be solved by first approximating it by the Fokker-Planck equation. Then this equation is discretized in space and time by a finite difference method. The method is compared to a Monte Carlo method by Gillespie. The method is applied to a four-dimensional problem of interest in the regulation of cell processes.
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| 10. |
- Fange, David, et al.
(författare)
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Stochastic reaction-diffusion kinetics in the microscopic limit
- 2010
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 107:46, s. 19820-19825
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Tidskriftsartikel (refereegranskat)abstract
- Quantitative analysis of biochemical networks often requires consideration of both spatial and stochastic aspects of chemical processes. Despite significant progress in the field, it is still computationally prohibitive to simulate systems involving many reactants or complex geometries using a microscopic framework that includes the finest length and time scales of diffusion-limited molecular interactions. For this reason, spatially or temporally discretized simulations schemes are commonly used when modeling intracellular reaction networks. The challenge in defining such coarse-grained models is to calculate the correct probabilities of reaction given the microscopic parameters and the uncertainty in the molecular positions introduced by the spatial or temporal discretization. In this paper we have solved this problem for the spatially discretized Reaction-Diffusion Master Equation; this enables a seamless and physically consistent transition from the microscopic to the macroscopic frameworks of reaction-diffusion kinetics. We exemplify the use of the methods by showing that a phosphorylation-dephosphorylation motif, commonly observed in eukaryotic signaling pathways, is predicted to display fluctuations that depend on the geometry of the system.
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| 11. |
- Ferm, Lars, et al.
(författare)
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Adaptive, Conservative Solution of the Fokker-Planck Equation in Molecular Biology
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Fokker-Planck equation on conservation form is discretized by a finite volume method and advanced in time by a linear multistep method. The grid cells are refined and coarsened in blocks of the grid depending on an estimate of the spatial discretization error and the time step is chosen to satisfy a tolerance on the temporal discretization error. The solution is conserved across the block boundaries so that the total probability is constant. A similar effect is achieved by rescaling the solution. The steady state solution is determined as the eigenvector corresponding to the zero eigenvalue. The method is applied to the solution of a problem with two molecular species and the simulation of a circadian clock. Comparison is made with a stochastic method.
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| 12. |
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| 13. |
- Glas, Gerie J., et al.
(författare)
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Ventilation practices in burn patients-an international prospective observational cohort study
- 2021
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Ingår i: BURNS & TRAUMA. - : Oxford University Press. - 2321-3868 .- 2321-3876. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is unknown whether lung-protective ventilation is applied in burn patients and whether they benefit from it. This study aimed to determine ventilation practices in burn intensive care units (ICUs) and investigate the association between lung-protective ventilation and the number of ventilator-free days and alive at day 28 (VFD-28). Methods: This is an international prospective observational cohort study including adult burn patients requiring mechanical ventilation. Low tidal volume (V-T) was defined as V-T <= 8 mL/kg predicted body weight (PBW). Levels of positive end-expiratory pressure (PEEP) and maximum airway pressures were collected. The association between V-T and VFD-28 was analyzed using a competing risk model. Ventilation settings were presented for all patients, focusing on the first day of ventilation. We also compared ventilation settings between patients with and without inhalation trauma. Results: A total of 160 patients from 28 ICUs in 16 countries were included. Low V-T was used in 74% of patients, median V-T size was 7.3 [interquartile range (IQR) 6.2-8.3] mL/kg PBW and did not differ between patients with and without inhalation trauma (p= 0.58). Median VFD-28 was 17 (IQR 0-26), without a difference between ventilation with low or high V-T (p= 0.98). All patients were ventilated with PEEP levels >= 5 cmH(2)O; 80% of patients had maximum airway pressures <30 cmH(2)O. Conclusion: In this international cohort study we found that lung-protective ventilation is used in the majority of burn patients, irrespective of the presence of inhalation trauma. Use of low V-T was not associated with a reduction in VFD-28.
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| 14. |
- Gus, Eduardo, et al.
(författare)
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Burn unit design - the missing link for quality and safety.
- 2021
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Ingår i: Journal of Burn Care & Research. - : Oxford University Press. - 1559-047X .- 1559-0488. ; 42:3, s. 369-375
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Forskningsöversikt (refereegranskat)abstract
- The relationship between infrastructure, technology, model of care and human resources influences patient outcomes and safety, staff productivity and satisfaction, retention of personnel, and treatment and social costs. This concept underpins the need for evidence-based design, and has been widely adopted to inform hospital infrastructure planning. The aim of this review is to establish evidence-based, universally-applicable key features of a burn unit that support function in a comprehensive patient-centred model of care. A literature search in medical, architectural and engineering databases was conducted. Burn associations' guidelines and relevant articles published in English, between 1990 and 2020, were included, and the available evidence is summarized in the review. Few studies have been published on burn unit design in the last thirty years. Most of them focus on the role of design in infection control and prevention, and consist primarily of descriptive or observational reports, opportunistic historical cohort studies, and reviews. The evidence available in the literature is not sufficient to create a definitive infrastructure guideline to inform burn unit design, and there are considerable difficulties in creating evidence that will be widely applicable. In the absence of a strong evidence base, consensus guidelines on burn unit infrastructure should be developed, to help healthcare providers, architects and engineers make informed decisions, when designing new or renovated facilities.
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| 15. |
- Gustafsson, Lars L., et al.
(författare)
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The 'wise list'- a comprehensive concept to select, communicate and achieve adherence to recommendations of essential drugs in ambulatory care in Stockholm
- 2011
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Ingår i: Basic & Clinical Pharmacology & Toxicology. - Copenhagen : Blackwell Publishing. - 1742-7835 .- 1742-7843. ; 108:4, s. 224-233
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to present and evaluate the impact of a comprehensive strategy over 10 years to select, communicate and achieve adherence to essential drug recommendations (EDR) in ambulatory care in a metropolitan healthcare region. EDRs were issued and launched as a 'Wise List' by the regional Drug and Therapeutics Committee in Stockholm. This study presents the concept by: (i) documenting the process for selecting, communicating and monitoring the impact of the 'Wise List'; (ii) analysing the variation in the number of drug substances recommended between 2000 and 2010; (iii) assessing the attitudes to the 'Wise List' among prescribers and the public; (iv) evaluating the adherence to recommendations between 2003 and 2009. The 'Wise List' consistently contained 200 drug substances for treating common diseases. The drugs were selected based on their efficacy, safety, suitability and cost-effectiveness. The 'Wise List' was known among one-third of a surveyed sample of the public in 2002 after initial marketing campaigns. All surveyed prescribers knew about the concept and 81% found the recommendations trustworthy in 2005. Adherence to recommendations increased from 69% in 1999 to 77% in 2009. In primary care, adherence increased from 83% to 87% from 2003 to 2009. The coefficient of variation (CV%) decreased from 6.1% to 3.8% for 156 healthcare centres between these years. The acceptance of the 'Wise List' in terms of trust among physicians and among the public and increased adherence may be explained by clear criteria for drug recommendations, a comprehensive communication strategy, electronic access to recommendations, continuous medical education and involvement of professional networks and patients.
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| 16. |
- Kaaks, Rudolf, et al.
(författare)
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Lag Times between Lymphoproliferative Disorder and Clinical Diagnosis of Chronic Lymphocytic Leukemia : A Prospective Analysis Using Plasma Soluble CD23
- 2015
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Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - 1055-9965 .- 1538-7755. ; 24:3, s. 538-545
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Tidskriftsartikel (refereegranskat)abstract
- Background: Chronic lymphocytic leukemia (CLL) is a chronic disease that often progresses slowly from a precursor stage, monoclonal B-cell lymphocytosis (MBL), and that can remain undiagnosed for a long time. Methods: Within the European Prospective Investigation into Cancer cohort, we measured prediagnostic plasma sCD23 for 179 individuals who eventually were diagnosed with CLL and an equal number of matched control subjects who remained free of cancer. Results: In a very large proportion of CLL patients' plasma sCD23 was clearly elevated 7 or more years before diagnosis. Considering sCD23 as a disease predictor, the area under the ROC curve (AUROC) was 0.95 [95% confidence interval (CI), 0.90-1.00] for CLL diagnosed within 0.1 to 2.7 years after blood measurement, 0.90 (95% CI, 0.86-0.95) for diagnosis within 2.8 to 7.3 years, and 0.76 (95% CI, 0.65-0.86) for CLL diagnosed between 7.4 and 12.5 years. Even at a 7.4-year and longer time interval, elevated plasma sCD23 could predict a later clinical diagnosis of CLL with 100% specificity at > 45% sensitivity. Conclusions: Our findings provide unique documentation for the very long latency times during which measurable B-cell lymphoproliferative disorder exists before the clinical manifestation of CLL. Impact: Our findings have relevance for the interpretation of prospective epidemiologic studies on the causes of CLL in terms of reverse causation bias. The lag times indicate a time frame within which an early detection of CLL would be theoretically possible. (c) 2014 AACR.
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| 17. |
- Koulaouzidis, Anastasios, et al.
(författare)
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Macroscopic findings in collagenous colitis : A multi-center, retrospective, observational cohort study
- 2017
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Ingår i: Annals of Gastroenterology. - : Hellenic Society of Gastroenterology. - 1108-7471 .- 1792-7463. ; 30:3, s. 309-314
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Tidskriftsartikel (refereegranskat)abstract
- Background Collagenous colitis (CC) is by definition a histological diagnosis. However, colonoscopy often reveals characteristic endoscopic findings. The aim of this study was to evaluate the frequency and type of endoscopic findings in patients diagnosed with CC in 4 participating centers. Methods This was a retrospective study; the databases of 2 university hospitals in Edinburgh (Scotland) and Malmö (Sweden), and 2 district general hospitals in Tomelloso (Spain) and Gateshead (England) were interrogated for patients diagnosed with CC between May 2008 and August 2013. Endoscopy reports and images were retrieved and reviewed; data on lesions, sedation, bowel preparation and endoscopist experience were abstracted. Categorical data are reported as mean±SD. Fischer’s exact, chi-square and t (unpaired) tests were used to compare datasets. A two-tailed P-value of <0.05 was considered statistically significant. Results 607 patients (149 male, mean age 66.9±12.25 years) were diagnosed with CC. A total of 108/607 (17.8%) patients had one or more suggestive endoscopy findings: i.e., mucosal erythema/edema, 91/607 (15%); linear colonic mucosal defects, 12/607 (2%); or mucosal scarring, 5/607 (0.82%). For colonic mucosa erythema, there was no difference in the odds of finding erythema with the use of different bowel preparation methods (P=0.997). For colonic mucosal defects there was some evidence (P=0.005) that patients colonoscoped by experienced endoscopists had 87% less odds of developing such defects. Moreover, there was evidence that analgesia reduced the odds of developing mucosal defects by 84%. Conclusion A significant minority of patients with CC have endoscopic findings in colonoscopy. The description of such findings appears to be related to the endoscopist’s experience.
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| 18. |
- Larsson, Johanna K, et al.
(författare)
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Cancer Risk in Collagenous Colitis
- 2019
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 8:11
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Tidskriftsartikel (refereegranskat)abstract
- Data on malignancy in patients with collagenous colitis (CC) is scarce. We aimed to determine the incidence of cancers in patients with CC. In a two-stages, observational study, data on cancers in patients diagnosed with CC during 2000-2015, were collected from two cohorts. The risk was calculated according to the age-standardized rate for the first cohort and according to the standardized incidence ratio for the second cohort. The first cohort comprised 738 patients (394 from Scotland and 344 from Sweden; mean age 71 +/- 11 and 66 +/- 13 years, respectively). The incidence rates for lung cancer (RR 3.9, p = 0.001), bladder cancer (RR 9.2, p = 0.019), and non-melanoma skin cancer (NMSC) (RR 15, p = 0.001) were increased. As the majority of NMSC cases (15/16) came from Sweden, a second Swedish cohort, comprising 1141 patients (863 women, mean age 65 years, range 20-95 years) was collected. There were 93 cancer cases (besides NMSC). The risk for colon cancer was decreased (SIR 0.23, p= 0.0087). The risk for cutaneous squamous cell carcinoma was instead markedly increased (SIR 3.27, p = 0.001).
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| 19. |
- Mirdell, Robin, 1989-
(författare)
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Blood Flow Dynamics in Burns
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives:Burns of intermediate thickness are hard to evaluate clinically. This often leads to unnecessary delays of up to 14 days before a surgical decision can be made. To counter this, several objective methods have been developed to determine the healing potential of the wound. Over the years, measurement of perfusion has proven to be the most successful method for evaluation of healing potential. Laser Doppler imaging (LDI) is currently the most used method and can determine surgical need 2 days after injury with an accuracy >90%. There are however emerging techniques like laser speckle contrast imaging (LSCI), which also measure perfusion. LSCI have several advantages over LDI and is easier to use. LSCI can also investigate aspects of the microcirculation, previously not possible with LDI. The aim of this thesis was to investigate LSCI’s ability to evaluate surgical need in burns of indeterminate partial-thickness. The first objective was to investigate the dynamics of perfusion the first 14 days after injury. The purpose was to find the optimal time-window for perfusion measurements. The next goal was to determine the accuracy of different perfusion cut-offs. In this second study, the benefit of a subsequent measurement was also investigated. After this, interobserver variation between different profession groups was studied. Both the agreement of perfusion measurements and observer assessments were evaluated. Finally, cardiac vasomotion in combination with perfusion (pulsatility) was investigated as a method to determine surgical need <48 hours after injury. Methods:Perfusion was measured in a total of 77 patients at the Department of Plastic Surgery, Hand Surgery and Burns at Linköping University Hospital, Sweden. Most of these patients were children and the most common type of burn was scalds. A laser speckle contrast imager (PeriCam PSI System, Perimed AB, Järfälla, Sweden) was used to measure perfusion. Results: In the first paper we showed a clear relation between perfusion dynamics and the healing potential of the wound. The changes in perfusion were largest the first 5 days after injury, why this time interval was selected for subsequent papers. Perfusion measurements done day 3-4 after injury could predict surgical need with a sensitivity of 100% (95% CI: 83.9-100%) and a specificity of 90.4% (95% CI: 83.8-94.9%). If two measurements were used, <24 hours and 3-4 days after injury, the accuracy was 100%. Furthermore, we found that different observers could consistently predict perfusion, while there was a large variation in their clinical assessments. This was not improved by extensive burn experience. Finally, pulsatility could be used to predict surgical need the same day as the injury occurred with a sensitivity of 100% (95% CI: 88.1-100%) and a specificity of 98.8% (95% CI: 95.7- 99.9%). Conclusions: LSCI is a promising method for evaluation of burns and provides several benefits over LDI. The surgical need of burns can be determined mere hours after injury when pulsatility is measured. However, the benefits of early scald diagnostics in children with LSCI need to be evaluated in a prospective study before the method is ready for routine clinical use.
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| 20. |
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| 21. |
- Powell, Kipton J., et al.
(författare)
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Chemical speciation of environmentally significant heavy metals with inorganic ligands - Part 1: The Hg2+-Cl-, OH-, CO32-, SO42-, and PO43- aqueous systems - (IUPAC technical report)
- 2005
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Ingår i: Pure and Applied Chemistry. - : Walter de Gruyter GmbH. - 0033-4545 .- 1365-3075. ; 77:4, s. 739-800
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Tidskriftsartikel (refereegranskat)abstract
- This document presents a critical evaluation of the equilibrium constants and reaction enthalpies for the complex formation reactions between aqueous Hg(II) and the common environmental inorganic ligands Cl-, OH-, CO32-, SO42-, and PO43-. The analysis used data from the IUPAC Stability Constants database, SC-Database, focusing particularly on values for 25 &DEG; C and perchlorate media. Specific ion interaction theory (SIT) was applied to reliable data available for the ionic strength range I-c &LE; 3.0 mol dm(-3). Recommended values of log(10) β(p,q,r)&DEG; and the associated reaction enthalpies, &UDelta;H-r(m)&DEG;, valid at I-m = 0 mol kg(-1) and 25 &DEG; C, were obtained by weighted linear regression using the SIT equations. Also reported are the equations and specific ion interaction coefficients required to calculate log(10) β(p,q,r) values at higher ionic strengths and other temperatures. A similar analysis is reported for the reactions of H+ with CO32- and PO43-. Diagrams are presented to show the calculated distribution of Hg(II) amongst these inorganic ligands in model natural waters. Under typical environmental conditions, Hg(II) speciation is dominated by the formation of HgCl2(aq), Hg(OH)Cl(aq), and Hg(OH)(2)(aq).
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| 22. |
- Powell, Kipton J, et al.
(författare)
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Chemical speciation of environmentally significant metals : an IUPAC contribution to reliable and rigorous computer modelling
- 2015
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Ingår i: Chemistry International. - : Walter de Gruyter. - 0193-6484 .- 1365-2192. ; 37:1, s. 15-19
-
Tidskriftsartikel (refereegranskat)abstract
- The mobility and bioavailability of metal ions in natural waters depend on their chemical speciation, which involves a distribution of the metal ions between different complex (metal-ligand) species, colloid-adsorbed species and insoluble phases, each of which may be kinetically labile or inert. For example, in fresh water the metal ions are distributed among organic complexes (e.g., humates), colloids (e.g., as surface-adsorbed species on colloidal phases such as FeOOH), solid phases (e.g., hydroxide, oxide, carbonate mineral phases), and labile complexes with the simple inorganic anionic ligands commonly present in natural waters (e.g., for ZnII, the aqueous species, Zn2+, ZnOH+, Zn(OH)2(aq), Zn2OH3+, ZnSO4(aq), ZnCO3(aq)…).
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| 23. |
- Powell, Kipton J., et al.
(författare)
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Chemical speciation of environmentally significant metals with inorganic ligands Part 2: The Cu2+-OH-, Cl-, CO32-, SO42-, and PO43- systems (IUPAC Technical Report)
- 2007
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Ingår i: Pure and Applied Chemistry. - : Walter de Gruyter GmbH. - 0033-4545 .- 1365-3075. ; 79:5, s. 895-950
-
Forskningsöversikt (refereegranskat)abstract
- Complex formation between CuII and the common environmental ligands Cl-, OH-, CO32-, SO42-, and PO43- can have a significant effect on CuII speciation in natural waters with low concentrations of organic matter. Copper(II) complexes are labile, so the CuII distribution amongst these inorganic ligands can be estimated by numerical modeling if reliable values for the relevant stability (formation) constants are available. This paper provides a critical review of such constants and related thermodynamic data. It recommends values of log10βp,q,r° valid at Im = 0 mol kg-1 and 25 °C (298.15 K), along with the equations and specific ion interaction coefficients required to calculate log10βp,q,r values at higher ionic strengths. Some values for reaction enthalpies, ΔrHm, are also reported where available. In weakly acidic fresh water systems, in the absence of organic ligands, CuII speciation is dominated by the species Cu2+(aq), with CuSO4(aq) as a minor species. In seawater, it is dominated by CuCO3(aq), with Cu(OH)+, Cu2+(aq), CuCl+, Cu(CO3)OH-, Cu(OH)2(aq), and Cu(CO3)22- as minor species. In weakly acidic saline systems, it is dominated by Cu2+(aq) and CuCl+, with CuSO4(aq) and CuCl2(aq) as minor species.
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| 24. |
- Powell, Kipton J, et al.
(författare)
-
Chemical speciation of environmentally significant metals with inorganic ligands. Part 3: The Pb2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)
- 2009
-
Ingår i: Pure and Applied Chemistry. - 0033-4545 .- 1365-3075. ; 81:12, s. 2425-76
-
Tidskriftsartikel (refereegranskat)abstract
- Complex formation between PbII and the common environmental inorganic ligands, Cl–, OH–, CO32–, SO42–, and PO43–, can be significant in natural waters with low concentrations of organic matter. Numerical modeling of the speciation of PbII amongst these inorganic ligands requires reliable values for the relevant stability (formation) constants. This paper provides a critical review of such constants and related thermodynamic data. It recommends values of log10 βp,q,r° valid at Im = 0 mol kg–1 and 25 °C (298.15 K), along with the equations and empirical coefficients required to calculate log10 βp,q,r values at higher ionic strengths using the Brønsted–Guggenheim–Scatchard specific ion interaction theory (SIT). Some values for reaction enthalpies, ΔrH, are also reported. In weakly acidic fresh water systems (–log10 {[H+]/c°} < 6), the speciation of PbII is similar to that of CuII. In the absence of organic ligands, PbII speciation is dominated by Pb2+(aq), with PbSO4(aq) as a minor species. In weakly alkaline solutions, 8.0 < –log10 {[H+]/c°} < 9.0, the speciation is dominated by the carbonato species PbCO3(aq) and Pb(CO3)22–. In weakly acidic saline systems (–log10 {[H+]/c°} < 6), the speciation is dominated by PbCln(2–n)+ complexes, (n = 0–3), with Pb2+(aq) as a minor species. In this medium (and in seawater), the speciation contrasts with that of CuII because of the higher stability of the Pb2+-chlorido- complexes. In seawater at –log10 {[H+]/c°} = 8.2, the calculated speciation is less well defined, although it is clearly dominated by the uncharged species PbCO3(aq) (41 % of [Pb]T) with a significant contribution (16 %) from Pb(CO3)Cl– and minor contributions (5–10 %) from PbCln(2–n)+, (n = 0–3) and Pb(CO3)22–. The uncertainty in calculations of PbII speciation in seawater arises from (a) the large uncertainty in the stability constant for the apparently dominant species PbCO3(aq), (b) the reliance on statistical predictions for stability constants of the ternary species Pb(CO3)Cl– and Pb(CO3)OH–, and (c) the uncertainty in the stability constant for PbCl42–, the available value being considered "indicative" only. There is scope for additional detailed high-quality measurements in the Pb2+ + CO32– + Cl– system.
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| 25. |
- Powell, Kipton J., et al.
(författare)
-
Chemical speciation of environmentally significant metals with inorganic ligands. Part 5: The Zn2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)
- 2013
-
Ingår i: Pure and Applied Chemistry. - 0033-4545 .- 1365-3075. ; 85:12, s. 2249-2311
-
Tidskriftsartikel (refereegranskat)abstract
- The numerical modeling of ZnII speciation amongst the environmental inorganic ligands Cl–, OH–, CO32–, SO42–, and PO43– requires reliable values for the relevant stability (formation) constants. This paper compiles and provides a critical review of these constants and related thermodynamic data. It recommends values of log10 βp,q,r° valid at Im = 0 mol·kg–1 and 25 °C (298.15 K), and reports the empirical reaction ion interaction coefficients, ∆ε, required to calculate log10 βp,q,r values at higher ionic strengths using the Brønsted–Guggenheim–Scatchard specific ion interaction theory (SIT). Values for the corresponding reaction enthalpies, ∆rH, are reported where available. There is scope for additional high-quality measurements for the Zn2+ + H+ + CO32– system and for the Zn2+ + OH– and Zn2+ + SO42– systems at I > 0. In acidic and weakly alkaline fresh water systems (pH < 8), in the absence of organic ligands (e.g., humic substances), ZnII speciation is dominated by Zn2+(aq). In this respect, ZnII contrasts with CuII and PbII (the subjects of earlier reviews in this series) for which carbonato- and hydroxido- complex formation become important at pH > 7. The speciation of ZnII is dominated by ZnCO3(aq) only at pH > 8.4. In seawater systems, the speciation at pH = 8.2 is dominated by Zn2+(aq) with ZnCl+, Zn(Cl)2(aq), ZnCO3(aq), and ZnSO4(aq) as minor species. This behaviour contrasts with that for CuII and PbII for which at the pH of seawater in equilibrium with the atmosphere at 25 °C (log10 {[H+]/c°} ≈ 8.2) the MCO3(aq) complex dominates over the MCln(2–n)+ species. The lower stability of the different complexes of ZnII compared with those of CuII, PbII, and CdII is also illustrated by the percentage of uncomplexed M2+ in seawater, which is ca. 55, 3, 2, and 3.3 % of [MII]T, respectively.
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| 26. |
- Powell, Kipton J, et al.
(författare)
-
Chemical speciation of environmentally significant metals with inorganic ligands : Part 4: The Cd2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)
- 2011
-
Ingår i: Pure and Applied Chemistry. - 0033-4545 .- 1365-3075. ; 83:5, s. 1163-1214
-
Tidskriftsartikel (refereegranskat)abstract
- The numerical modeling of CdII speciation amongst the environmental inorganic ligands Cl–, OH–, CO32–, SO42–, and PO43– requires reliable values for the relevant stability (formation) constants. This paper compiles and provides a critical review of these constants and related thermodynamic data. It recommends values of log10 βp,q,r° valid at Im = 0 mol kg–1 and 25 °C (298.15 K), along with the equations and empirical reaction ion interaction coefficients, ∆ε , required to calculate log10 βp,q,r values at higher ionic strengths using the Brønsted–Guggenheim–Scatchard specific ion interaction theory (SIT). Values for the corresponding reaction enthalpies, ∆rH, are reported where available. Unfortunately, with the exception of the CdII-chlorido system and (at low ionic strengths) the CdII-sulfato system, the equilibrium reactions for the title systems are relatively poorly characterized. In weakly acidic fresh water systems (–log10 {[H+]/c°} < 6), in the absence of organic ligands (e.g., humic substances), CdII speciation is dominated by Cd2+(aq), with CdSO4(aq) as a minor species. In this respect, CdII is similar to CuII [2007PBa] and PbII [2009PBa]. However, in weakly alkaline fresh water solutions, 7.5 < –log10 {[H+]/c°} < 8.6, the speciation of CdII is still dominated by Cd2+(aq), whereas for CuII [2007PBa] and PbII [2009PBa] the carbonato- species MCO3(aq) dominates. In weakly acidic saline systems (–log10 {[H+]/cϒ} < 6; –log10 {[Cl–]/c°} < 2.0) the speciation is dominated by CdCln(2–n)+ complexes, (n = 1–3), with Cd2+(aq) as a minor species. This is qualitatively similar to the situation for CuII and PbII. However, in weakly alkaline saline solutions, including seawater, the chlorido- complexes still dominate the speciation of CdII because of the relatively low stability of CdCO3(aq). In contrast, the speciation of CuII [2007PBa] and PbII [2009PBa] in seawater is dominated by the respective species MCO3(aq). There is scope for additional high-quality measurements in the Cd2+ + H+ + CO32– system as the large uncertainties in the stability constants for the Cd2+-carbonato complexes significantly affect the speciation calculations.
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| 27. |
- Rönngren, Lars, et al.
(författare)
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Surface reactions in aqueous metal sulfide systems : 2. Ion exchange and acid/base reactions at the ZnSH2O interface
- 1991
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Ingår i: Journal of Colloid and Interface Science. - 0021-9797 .- 1095-7103. ; 145:2, s. 396-404
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Tidskriftsartikel (refereegranskat)abstract
- The amphoteric properties of hydrous ZnS surfaces as well as an ion exchange reaction between surface coordinated Zn2+ ions and H+ ions of the aqueous phase have been established. The measurements were performed as potentiometric titrations in 0.1 M NaClO4 medium at 25°C. Besides measuring -log[H+] by using a glass electrode, -log[S2-] was recorded (Ag/Ag2S selective electrode). In addition, the total concentrations of H+, Zn2+, and S were analyzed as a function of -log[H+] of the bulk solution. Synthetically prepared ZnS and the mineral sphalerite were studied. Bro¨nsted acidity constants pK1s = 6.91 and pK2s = 10.28 for synthetic ZnS, and pK1s = 7.14 and pK2s = 10.29 for sphalerite, were established, which implies -log[H+] of zero proton condition equal to 8.60 and 8.72, respectively. Furthermore, the ion exchange reaction ≡SZn + 2H+ ↔ ≡SH2 + Zn2+ was characterized within the range 4 ≤ -log[H+] ≤ 7, with log K = 9.59 and 9.65. Experimental data were evaluated on the basis of the constant capacitance model by using the computer program FITEQL. The "best" fit to experimental data was obtained by assuming no charge dependence of K1s and K2s.
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| 28. |
- Sjöberg, Linnea, 1989, et al.
(författare)
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DEVELOPMENT OF A PROTOTYPE FOR REFEREES TO MONITOR WHIP USE IN HORSE RACING
- 2017
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Ingår i: ISES 2017 Down Under. - 9781864673067
-
Konferensbidrag (refereegranskat)abstract
- There is no standard surveillance system for modern flat horse racing in Sweden, so the surveillance camera placement and image quality varies between tracks. Reported whip misuse and unauthorised whipping often occur outside of the camera’s view and are therefore unrecorded. Thorough investigation of the current monitoring system used in Sweden revealed concerns about whether the stewards have enough time to estimate the number of whip strikes per horse, even when camera quality is sufficient, and has led to the development of an enhanced whip system. The system prototype offers a technical solution for the supervision of whip use in modern horse racing, and it would be useful in countries where there are regulations limiting the number of strikes. Current specifications allow the system to record the attributes and number of strikes and to relay the data contemporaneously to the stewards. The system does not interfere with the operation of the camera monitoring system. Since the number of strikes is reported with total accuracy, stewards are afforded more time to focus on matters of interference and actions that are important to the final result list. The prototype is a whip with a custom-made force sensor placed on both sides of the cushion pad. The sensors measure an area 24mm wide by 275mm long and cover the entire padded part of the approved race whip. The sensor is constructed of polyester that is 0.203mm thick. The force sensor is connected to a microcontroller mounted in the handle of the whip. The microcontroller processes the sensor data and sends the information via radio waves up to 1.7km in outdoor conditions to a second microcontroller located in the steward’s office. The whip strike sensor prototype is able to distinguish between a wave of the arm that leads to no impact and a strike. The software allows the force of each strike impact to be recorded. The intention is to embed the whip strike sensor within the body of whips used in a range of equestrian disciplines in which whip use is permitted. The possibility to register the properties of whip strikes will help to safeguard the welfare of horses used in these disciplines and provide information to the equestrian community that could change the way whips are used in training and racing. Lay person message: The whipping of horses in racing leads to concerns about animal welfare globally. A whip strike sensor prototype has been developed that will facilitate detailed exploration of the effect whips have on horses and allow stewards to accurately assess the number of strikes made and forces used. It is intended to integrate strike sensors into whips used in disciplines where whipping is allowed; this will help to safeguard the welfare of horses used in these disciplines.
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| 29. |
- Sjöberg, Paul, et al.
(författare)
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Fokker-Planck approximation of the master equation in molecular biology
- 2005
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The master equation of chemical reactions is solved by first approximating it by the Fokker-Planck equation. Then this equation is discretized in the state space and time by a finite volume method. The difference between the solution of the master equation and the discretized Fokker-Planck equation is analyzed. The solution of the Fokker-Planck equation is compared to the solution of the master equation obtained with Gillespie's Stochastic Simulation Algorithm (SSA) for problems of interest in the regulation of cell processes. The time dependent and steady state solutions are computed and for equal accuracy in the solutions, the Fokker-Planck approach is more efficient than SSA for low dimensional problems and high accuracy.
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| 30. |
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| 31. |
- Sjöberg, Paul, 1976-
(författare)
-
Numerical Methods for Stochastic Modeling of Genes and Proteins
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Stochastic models of biochemical reaction networks are used for understanding the properties of molecular regulatory circuits in living cells. The state of the cell is defined by the number of copies of each molecular species in the model. The chemical master equation (CME) governs the time evolution of the the probability density function of the often high-dimensional state space. The CME is approximated by a partial differential equation (PDE), the Fokker-Planck equation and solved numerically. Direct solution of the CME rapidly becomes computationally expensive for increasingly complex biological models, since the state space grows exponentially with the number of dimensions. Adaptive numerical methods can be applied in time and space in the PDE framework, and error estimates of the approximate solutions are derived. A method for splitting the CME operator in order to apply the PDE approximation in a subspace of the state space is also developed. The performance is compared to the most widely spread alternative computational method.
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| 32. |
- Sjöberg, Paul
(författare)
-
Numerical solution of the Fokker–Planck approximation of the chemical master equation
- 2005
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The chemical master equation (CME) describes the probability for the discrete molecular copy numbers that define the state of a chemical system. Each molecular species in the chemical model adds a dimension to the state space. The CME is a difference-differential equation which can be solved numerically if the state space is truncated at an upper limit of the copy number in each dimension. The size of the truncated CME suffers from an exponential growth for an increasing number of chemical species.In this thesis the chemical master equation is approximated by a continuous Fokker-Planck equation (FPE) which makes it possible to use sparser computational grids than for CME. FPE on conservative form is used to compute steady state solutions by computation of an extremal eigenvalue and the corresponding eigenvector as well as time-dependent solutions by an implicit time-stepping scheme.The performance of the numerical solution is compared to a standard Monte Carlo algorithm. The computational work for a solutions with the same estimated error is compared for the two methods. Depending on the problem, FPE or the Monte Carlo algorithm will be more efficient. FPE is well suited for problems in low dimensions, especially if high accuracy is desirable.
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| 33. |
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| 34. |
- Sjöberg, Paul
(författare)
-
PDE and Monte Carlo approaches to solving the master equation applied to gene regulation
- 2007
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Fokker-Planck equation (FPE) approximation is applied for a subspace of the state space of the chemical master equation (CME). The CME-FPE-hybrid method exploits the lower cost of the FPE approximation compared to the full CME. A fourth order finite difference approximation of the FPE part of the hybrid is described and demonstrated on a biologically relevant model in five dimensions.
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| 35. |
- Sjöberg, Ted
(författare)
-
Plasticity modelling of nickel based super alloy Alloy 718
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The ever growing demand on reduced fuel consumption in modern aircrafts puts high requirements on manufacturers to reduce weight in all parts of the aircraft. With a total weight of up to one fifth of an aircraft’s total operating weight, ways to decrease the weight of the engine systems are continuously sought. The containment structure that surrounds the fan and turbine in larger commercial aircrafts is designed to prevent any debris to escape and damage any other systems such as fuel tanks or fuselage in the event that a blade should come off. This structure adds considerable bulk to the engine and because of the importance of the containment structure any redesign needs to be thoroughly tested. The high costs associated with containment testing means industry is looking into the feasibility of substituting parts of the expensive experimental testing with more economical numerical simulations. In this thesis modelling of the plastic behaviour of the nickel based super alloy, called Alloy 718, is investigated in an effort to correctly model the material in numerical simulations. This material is one of the most widely used materials in the parts of an aircraft engine subjected to elevated temperatures due to its retained strength and resistance to corrosion and creep. The material models chosen to model the plastic behaviour were the widely used Johnson-Cook and Zerilli-Armstrong models, because of their proven applicability for wide ranges of strain rates. The models were calibrated using data collected from tensile testing performed in a high speed VHS machine from Instron. Tensile tests were performed at quasi-static conditions and raised strain rates up to 1000 s-1. With an induction coil testing was also performed at temperatures up to 650 oC. Fitting the models to the data gave models valid from quasi-static to high rate conditions. In order to test the accuracy of the models they need to be validated. For this purpose a reverse impact experiment using free flying discs impacting a long slender rod was designed. This design enables the force history to be accurately monitored throughout the impact, while still achieving high strain rates. An investigation into producing additional data for use in validation was also performed. This investigation utilized a series of high speed photographs on which shape measurements were carried out in order to find parameters such as plate velocity and average strain without interfering with the experimental results
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| 36. |
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| 37. |
- Spadini, Lorenzo, et al.
(författare)
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On the Stability of the AlOSi ( OH ) 32+ Complex in Aqueous Solution
- 2005
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Ingår i: Aquatic Geochemistry. - : Springer Netherlands. - 1380-6165 .- 1573-1421. ; 11:1, s. 21-31
-
Tidskriftsartikel (refereegranskat)abstract
- The complexation of aluminium(III) and silicon(IV) was studied in a simplified seawater medium (0.6 M Na(Cl)) at 25 °C. The measurements were performed as potentiometric titrations using a hydrogen electrode with OH − ions being generated coulometrically. The total concentrations of Si(IV) and Al(III) respectively [Si tot ] and [Al t ot], and −log[H +] were varied within the limits 0.3 < [Si tot ] < 2.5 mM, 0.5 < [Al tot ] < 2.6 mM, and 2 ≤ -log[H +] ≤ 4.2. Within these ranges of concentration, evidence is given for the formation of an AlSiO(OH) 3 2+ complex with a formation constant log β1,1-1 = −2.75 ± 0.1 defined by the reaction Al 3++Si (OH)4 ↔ AlOSi(OH) 3 2+ +H + An extrapolation of this value to I=0 gives log β1,1-1 = −2.30. The calculated value of log K (Al 3++SiO(OH) 3 − ↔ AlOSi(OH) 3 2+ ) = 6.72 (I=0.6 M) can be compared with corresponding constants for the formation of AlF 2+ and AlOH 2+ , which are equal to 6.16 and 8.20. Obviously, the stability of these Al(III) complexes decreases within the series OH −>SiO(OH) 3 − > F−
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| 38. |
- Spinelli, Angela, et al.
(författare)
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Prevalence of Severe Obesity among Primary School Children in 21 European Countries
- 2019
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Ingår i: Obesity Facts. - : S. Karger. - 1662-4025 .- 1662-4033. ; 12:2, s. 244-258
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The World Health Organization (WHO) European Childhood Obesity Surveillance Initiative (COSI) was established more than 10 years ago to estimate prevalence and monitor changes in overweight and obesity in children aged 6-9 years. Since then, there have been five rounds of data collection in more than 40 countries involving more than half a million children. To date, no comparative studies with data on severe childhood obesity from European countries have been published.OBJECTIVES: The aim of this work was to present the prevalence of severe obesity in school-aged children from 21 countries participating in COSI.METHOD: The data are from cross-sectional studies in 21 European WHO member states that took part in the first three COSI rounds of data collection (2007/2008, 2009/2010, 2012/2013). School-aged children were measured using standardized instruments and methodology. Children were classified as severely obese using the definitions provided by WHO and the International Obesity Task Force (IOTF). Analyses overtime, by child's age and mother's educational level, were performed in a select group of countries.RESULTS: A total of 636,933 children were included in the analysis (323,648 boys and 313,285 girls). The prevalence of severe obesity varied greatly among countries, with higher values in Southern Europe. According to the WHO definition, severe obesity ranged from 1.0% in Swedish and Moldovan children (95% CI 0.7-1.3 and 0.7-1.5, respectively) to 5.5% (95% CI 4.9-6.1) in Maltese children. The prevalence was generally higher among boys compared to girls. The IOTF cut-offs lead to lower estimates, but confirm the differences among countries, and were more similar for both boys and girls. In many countries 1 in 4 obese children were severely obese. Applying the estimates of prevalence based on the WHO definition to the whole population of children aged 6-9 years in each country, around 398,000 children would be expected to be severely obese in the 21 European countries. The trend between 2007 and 2013 and the analysis by child's age did not show a clear pattern. Severe obesity was more common among children whose mother's educational level was lower.CONCLUSIONS: Severe obesity is a serious public health issue which affects a large number of children in Europe. Because of the impact on educational, health, social care, and economic systems, obesity needs to be addressed via a range of approaches from early prevention of overweight and obesity to treatment of those who need it.
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| 39. |
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| 40. |
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| 41. |
- Westergren, Jens, et al.
(författare)
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Acute exercise as active inference in chronic musculoskeletal pain, effects on gait kinematics and muscular activity in patients and healthy participants : a study protocol for a randomised controlled laboratory trial
- 2023
-
Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 13
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Chronic musculoskeletal pain is a highly prevalent, complex and distressing condition that may negatively affect all domains of life. In view of an active inference framework, and resting on the concept of allostasis, human movement per se becomes a prerequisite for health and well-being while chronic pain becomes a sign of a system unable to attenuate an allostatic load. Previous studies on different subgroups of chronic pain conditions have demonstrated alterations in gait kinematics and muscle activity, indicating shared disturbances in the motor system from long-term allostatic load. We hypothesise that such alterations exist in heterogenous populations with chronic musculoskeletal pain, and that exposure to acute and controlled exercise may attenuate these alterations. Therefore, the main aim of this study is to investigate the acute effects of exercise on gait kinematics and activity of the back and neck muscles during diverse walking conditions in patients with chronic musculoskeletal pain compared with a reference sample consisting of healthy participants.Methods and analysis: This two-sample two-armed parallel randomised controlled laboratory trial will include 40 participants with chronic musculoskeletal pain (>3 months) and 40 healthy participants. Participants will be randomly allocated to either 30 min of aerobic exercise or rest. Primary outcomes are gait kinematics (walking speed, step frequency, stride length, lumbar rotation, gait stability) and muscular activity (spatial and temporal) of the back and neck during diverse walking conditions. Secondary outcomes are variability of gait kinematics and muscle activity and subjective pain ratings assessed regularly during the trial.Ethics and dissemination: The study has been approved by the Regional Ethics Review Board in Uppsala, Sweden (#2018/307). Findings will be disseminated via conference presentations, publications in peer-reviewed journals and engagement with patient support groups and clinicians.
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