| 1. |
- Alfthan, Johan, et al.
(author)
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Linear constitutive model for mechano-sorptive creep in paper
- 2005
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In: International Journal of Solids and Structures. - : Elsevier BV. - 0020-7683 .- 1879-2146. ; 42:24-25, s. 6261-6276
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Journal article (peer-reviewed)abstract
- The creep of paper is accelerated by moisture cycling. This effect is known as mechano-sorptive creep. It is assumed that this is an effect of transient stresses produced during moisture content changes in combination with non-linear creep behaviour of the fibres. The stresses produced by the moisture content changes are often much larger than the applied mechanical loads. If this is the case, the mechanical loads are only a perturbation to the internal stress state, and it will appear as if the mechano-sorptive creep is linear in stress. It is possible to take advantage of this feature. In the present report the pure moisture problem is first solved. The mechanical load is then treated as a perturbation of the solution to the moisture problem. Using this strategy, it is possible to linearize a non-linear network model for mechano-sorptive creep and to formulate a continuum model. As a result, the number of variables in the model is reduced. This is a significant improvement as it will be possible to use the linearized model to describe the material in a finite element program and solve problems with complicated geometries.
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| 2. |
- Helmersson, Johanna, et al.
(author)
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Serum selenium predicts levels of F2-isoprostanes and prostaglandin F2alpha in a 27 year follow-up study of Swedish men
- 2005
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In: Free radical research. - : Informa UK Limited. - 1071-5762 .- 1029-2470. ; 39:7, s. 763-770
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Journal article (peer-reviewed)abstract
- Low concentrations of selenium (Se) predict mortality and cardiovascular diseases in some populations. The effect of Se on in vivo indicators of oxidative stress and inflammation, two important features of atherosclerosis, in human populations is largely unexplored. This study investigated the longitudinal association between serum selenium (s-Se) and a golden standard indicator of oxidative stress in vivo (8-iso-prostaglandin F2, a major F2-isoprostane), an indicator of cyclooxygenase (COX)-mediated inflammation (prostaglandin F2), high sensitive C-reactive protein (hsCRP), interleukin-6 (IL-6) and serum amyloid A protein (SAA) in a follow-up study of 27 years. The s-Se was measured in 615 Swedish men at 50 years of age in a health investigation. The status of oxidative stress and inflammation was evaluated in a re-investigation 27 years later by quantification of urinary 8-iso-PGF2 and 15-keto-dihydro- PGF2 (a major metabolite of PGF2) and serum hsCRP, SAA and IL-6. Men in the highest quartile of s-Se at age 50 had decreased levels of 8-iso-PGF2 compared to all lower quartiles and decreased levels of PGF2 compared to all lower quartiles at follow-up. These associations were independent of BMI, diabetes, hyperlipidemia, hypertension, smoking, -tocopherol and β-carotene at baseline. The s-Se was not associated with hsCRP, SAA or IL-6 at follow-up. In conclusion, high concentrations of s-Se predict reduced levels of oxidative stress and subclinical COX-mediated (but not cytokine-mediated) inflammation in a male population. The associations between Se, oxidative stress and inflammation, respectively, might be related to the proposed cardiovascular protective property of Se.
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| 3. |
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| 4. |
- Ärnlöv, Johan, et al.
(author)
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Serum and dietary beta-carotene and alpha-tocopherol and incidence of type 2 diabetes mellitus in a community-based study of Swedish men : report from the Uppsala Longitudinal Study of Adult Men (ULSAM) study
- 2009
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In: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 52:1, s. 97-105
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Journal article (peer-reviewed)abstract
- AIMS/HYPOTHESIS: To investigate the association of serum concentrations and dietary intake of beta-carotene and alpha-tocopherol with type 2 diabetes incidence. METHODS: Serum beta-carotene, alpha-tocopherol, lifestyle factors (BMI, physical activity and smoking) and metabolic factors (insulin sensitivity [homeostasis model assessment], acute insulin response and impaired fasting glucose) were analysed in 846 50-year-old non-diabetic Swedish men (participants in the Uppsala Longitudinal Study of Adult Men). Diabetes was identified in 245 participants at reinvestigations after 10, 20 and 27 years. At the 20 year reinvestigation, dietary intake of beta-carotene and alpha-tocopherol, insulin sensitivity (euglycaemic-hyperinsulinaemic clamp) and insulin secretion (early insulin response in OGTT) were determined. RESULTS: The highest tertile of serum beta-carotene at age 50 (>0.335 mumol/l) was associated with 59% lower risk of diabetes during follow-up compared with the lowest tertile (<0.210 mumol/l) after adjustment for lifestyle and metabolic factors (p < 0.01). The highest tertile of lipid-corrected serum alpha-tocopherol at age 50 (>3.67 mumol/mmol) was associated with 46% lower risk of diabetes compared with the lowest tertile (<3.25 mumol/mmol) independently of metabolic factors (p < 0.05). Moreover, lower serum beta-carotene and alpha-tocopherol concentrations were independently associated with impaired insulin sensitivity (p < 0.001), but not with early insulin response, in a subsample of non-diabetic individuals 20 years later. Dietary intake of beta-carotene and alpha-tocopherol independently predicted type 2 diabetes during 7 years of follow-up. CONCLUSIONS/INTERPRETATION: Serum concentrations and dietary intakes of beta-carotene and alpha-tocopherol independently predicted insulin resistance and type 2 diabetes incidence during 27 years of follow-up in a community-based study of men. This result supports the importance of impaired antioxidant status for the development of insulin resistance and type 2 diabetes.
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| 5. |
- Örtegren, Jonas, et al.
(author)
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Inkjet Printing Dynamics : Influence on Ink Distribution in Paper and Print Quality
- 2007
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In: NIP 23: 23RD INTERNATIONAL CONFERENCE ON DIGITAL PRINTING TECHNOLOGIES, TECHNICAL PROGRAM AND PROCEEDINGS/DIGITAL FABRICATION 2007. - : The Society for Imaging Science and Technology. - 9780892082735 ; , s. 595-598
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Conference paper (peer-reviewed)abstract
- Inkjet technology is becoming established as a production method and emerges as a printing technology for printing functionalities on various media. The development has encouraged intensified research in the fields of inkjet technology and paper media. The work presented here is pail of a research program that attempts to bridge the gap between the two disciplines. The overall objective is to control and improve the print quality and print functionality by observing and controlling the dynamic processes that occur in paper media in the inkjet printing process. Detailed information about the dynamic processes is however not available with the experimental methods present today, and improvements of experimental techniques is consequently a prerequisite for a better understanding. Therefore, inkjet printing machines were built and tested The printers allow for inkjet printing with various types of inks and print heads at freely chosen paper feeding speed Methods to study the inkjet printing process in-situ by use of camera and high-speed video camera were developed It is shown that the in-situ methods capture spreading and absorption processes of inkjet droplets on still-standing paper and paper fed at high speed The in-situ measurements and analysis are discussed in terms of relevant print quality parameters.
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