| 1. |
- Moberg, Christina, et al.
(författare)
-
De unga gör helt rätt när de stämmer staten
- 2022
-
Ingår i: Aftonbladet. - 1103-9000.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Lindskog, Bengt I., et al.
(författare)
-
Medicinsk terminologi
- 2004
-
Bok (övrigt vetenskapligt/konstnärligt)
|
|
| 6. |
- Mikulskis, Paulius, et al.
(författare)
-
Binding affinities in the SAMPL3 trypsin and host-guest blind tests estimated with the MM/PBSA and LIE methods.
- 2012
-
Ingår i: Journal of Computer-Aided Molecular Design. - : Springer Science and Business Media LLC. - 1573-4951 .- 0920-654X. ; 26:5, s. 527-541
-
Tidskriftsartikel (refereegranskat)abstract
- We have estimated affinities for the binding of 34 ligands to trypsin and nine guest molecules to three different hosts in the SAMPL3 blind challenge, using the MM/PBSA, MM/GBSA, LIE, continuum LIE, and Glide score methods. For the trypsin challenge, none of the methods were able to accurately predict the experimental results. For the MM/GB(PB)SA and LIE methods, the rankings were essentially random and the mean absolute deviations were much worse than a null hypothesis giving the same affinity to all ligand. Glide scoring gave a Kendall's τ index better than random, but the ranking is still only mediocre, τ = 0.2. However, the range of affinities is small and most of the pairs of ligands have an experimental affinity difference that is not statistically significant. Removing those pairs improves the ranking metric to 0.4-1.0 for all methods except CLIE. Half of the trypsin ligands were non-binders according to the binding assay. The LIE methods could not separate the inactive ligands from the active ones better than a random guess, whereas MM/GBSA and MM/PBSA were slightly better than random (area under the receiver-operating-characteristic curve, AUC = 0.65-0.68), and Glide scoring was even better (AUC = 0.79). For the first host, MM/GBSA and MM/PBSA reproduce the experimental ranking fairly good, with τ = 0.6 and 0.5, respectively, whereas the Glide scoring was considerably worse, with a τ = 0.4, highlighting that the success of the methods is system-dependent.
|
|
| 7. |
- Popova, Gergana, et al.
(författare)
-
Optimization of Tetrahydroindazoles as Inhibitors of Human Dihydroorotate Dehydrogenase and Evaluation of Their Activity and In Vitro Metabolic Stability
- 2020
-
Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 63:8, s. 3915-3934
-
Tidskriftsartikel (refereegranskat)abstract
- Human dihydroorotate dehydrogenase (DHODH), an enzyme in the de novo pyrimidine synthesis pathway, is a target for the treatment of rheumatoid arthritis and multiple sclerosis and is re-emerging as an attractive target for cancer therapy. Here we describe the optimization of recently identified tetrahydroindazoles (HZ) as DHODH inhibitors. Several of the HZ analogues synthesized in this study are highly potent inhibitors of DHODH in an enzymatic assay, while also inhibiting cancer cell growth and viability and activating p53-dependent transcription factor activity in a reporter cell assay. Furthermore, we demonstrate the specificity of the compounds toward the de novo pyrimidine synthesis pathway through supplementation with an excess of uridine. We also show that induction of the DNA damage marker gamma-H2AX after DHODH inhibition is preventable by cotreatment with the pancaspase inhibitor Z-VAD-FMK. Additional solubility and in vitro m etabolic stability profiling revealed compound 51 as a favorable candidate for preclinical efficacy studies.
|
|
| 8. |
- Sandberg, Maria, et al.
(författare)
-
Recent infections are associated with decreased risk of rheumatoid arthritis: a population-based case-control study.
- 2014
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 74:5, s. 904-907
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives Do recent infections affect the risk of rheumatoid arthritis (RA)? Methods We used the population-based case-control study EIRA (N= 6401) on incident RA and healthy controls, matched for sex, age, calendar period and area of residence. Gastroenteritis, urinary tract infection, genital infection, prostatitis, sinusitis, tonsillitis and pneumonia during the 2 years before inclusion in the study were investigated. Conditional logistic regression was used to calculate OR, adjusting for smoking and socioeconomic status. Results Infections in the gastrointestinal and urogenital tract before clinical onset were associated with a lowered risk of RA: gastroenteritis (OR= 0.71 (95% CI 0.63 to 0.80)), urinary tract infections (OR= 0.78 (95% CI 0.68 to 0.90)) and genital infections (OR= 0.80 (95% CI 0.64 to 1.00)), while a non-significant association of similar magnitude was observed for the less common prostatitis (OR= 0.64 (95% CI 0.38 to 1.08)). In contrast, no associations were observed for sinusitis, tonsillitis or pneumonia. Conclusions Gastrointestinal and urogenital infections, but not respiratory infections, are associated with a significantly lowered risk of RA. The results indicate that infections in general do not affect the risk for RA, but that certain infections, hypothetically associated with changes in the gut microbiome, could diminish the risk.
|
|
| 9. |
- Ahlström, Johan, et al.
(författare)
-
Galvanic corrosion properties of steel in water saturated concrete
- 2015
-
Ingår i: Materials and corrosion - Werkstoffe und Korrosion. - : Wiley. - 0947-5117 .- 1521-4176. ; 66:1, s. 67-75
-
Tidskriftsartikel (refereegranskat)abstract
- Aluminum-based sacrificial anodes were installed to reinforced concrete to stop ongoing corrosion in cooling water tunnels in a Swedish nuclear power plant. The steel rebars were also unintentionally connected to stainless steel water pumps. Therefore, the consumption rate of the sacrificial anodes was higher than predicted. An experimental and a field study were performed to assess if the steel rebar suffer from galvanic corrosion and if the stainless steel pumps are responsible alone for the high consumption rate. It was found from the experimental study that there is an increased risk of galvanic corrosion for steel rebar when the corrosion potential is raised to -200mV (SCE) for samples with 1% CL- by mass of cement and -500mV (SCE) for samples with 2% Cl- by mass of cement. The experimental results were compared with the corrosion potential measured in the cooling water tunnel where sacri ficial anodes were in use and not mounted at all. The cooling water tunnel without sacrificial anodes had generally more anodic corrosion potentials compared to the tunnel with anodes. The tunnel with anodes had also more anodic potentials closer to the stainless steel pumps than further away which means that the rebar is affected by the stainless steel pumps. However, the measured corrosion potentials in the tunnels were not as anodic as the potentials needed for high galvanic current measured in the experimental study.
|
|
| 10. |
- Ahmad, I., et al.
(författare)
-
Validity of diagnoses, treatment dates, and rating scales in the Swedish national quality register for electroconvulsive therapy
- 2022
-
Ingår i: Nordic Journal of Psychiatry. - : Informa UK Limited. - 0803-9488 .- 1502-4725. ; 76:2, s. 96-103
-
Tidskriftsartikel (refereegranskat)abstract
- Background The Swedish national quality register for electroconvulsive therapy (Q-ECT) contains data on patients receiving treatment with electroconvulsive therapy (ECT) in Sweden. Aim This study determined the validity of diagnoses, treatment dates, and rating scales in the Q-ECT by investigating the degree of accordance between data from the Q-ECT and patient records. Materials and methods From January 2016 to December 2017, 200 treatment series were randomly selected from the Q-ECT. The corresponding patient records were requested from the treating hospitals. Data on the indicative diagnosis, dates for the first and the last ECT session, and rating scales were compared between the Q-ECT and patient records using (i) a strict and (ii) a liberal method of assessment. Using the liberal method, each variable was assessed as accordant if it belonged to the same diagnosis group, or if the dates differed by less than 1 week, or ratings differed by only 1 point on the Clinical Global Impression Scale (CGI- S), or no more than 3 points on the Montgomery angstrom sberg Depression Rating Scale between the Q-ECT and the patient record. Results A total of 179 patient records were received. The strict method of assessment showed an accordance of 89% or higher for all studied variables. The liberal method showed an accordance of 95% or higher. Conclusions We conclude that data on the studied variables in the Q-ECT have high validity. However, limited use of some rating scales makes the results uncertain. Measures can be taken to further improve the data quality.
|
|
| 11. |
- Aleman, Soo, et al.
(författare)
-
Health check-ups and family screening allow detection of hereditary hemochromatosis with less advanced liver fibrosis and survival comparable with the general population
- 2011
-
Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 46:9, s. 1118-1126
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. The information concerning the morbidity and mortality of hereditary hemochromatosis is based primarily on clinical cohorts of symptomatic patients. The major aim of this study was to analyze the long-term prognosis for Swedish patients with this condition, with respect to both clinical features and survival, in relation to the route by which the disease was detected. Patients and methods. 373 patients with hemochromatosis detected through routine health checkups (n = 153), family screening (n = 44), symptoms of arthralgia (n = 23), investigation of other diseases/symptoms (n = 108) or signs of liver disease (n = 45) were monitored for a mean period of 11.9 +/- 5.8 years. The degree of liver fibrosis and survival were analyzed. Results. Overall survival among these patients was not significantly different from that of a matched normal population. The patients diagnosed through health check-ups and family screening were detected at an earlier age and had the highest rate of survival. Liver biopsy at the time of diagnosis revealed cirrhosis in 9% of those detected through the health check-ups and 5% in the case of family screening, compared with 13% for the group with arthralgia, 17% for other diseases/symptoms and 42% for liver disease. Conclusion. Health check-ups and family screening allow detection of hereditary hemochromatosis at an earlier age and with less advanced liver fibrosis, although a few of these patients have already developed cirrhosis. Our study indicates that iron indices should be included in health check-ups, and if abnormal, should lead to further investigation.
|
|
| 12. |
- Almqvist, Anna-Lena, et al.
(författare)
-
Papporna och motiven : Den svenska föräldraledigheten i ett geografiskt perspektiv
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet var att undersöka attityder, beteendemönster och erfarenheter hos föräldrapar i två län, när det gäller uttag av föräldrapenning. I de ingående länen har Västerbotten det högsta och Skåne det lägsta uttaget av föräldrapenning bland fäder. Två kommuner med högt och lågt föräldrapenninguttag bland fäder studerades i respektive län, Umeå och Lycksele samt Lund och Tomelilla. Metodologin var inspirerad av grounded theory. Data omfattade 32 intervjuer med fäder och mödrar, 20 intervjuer med nyckelpersoner inom Försäkringskassan, mödravården, kommunen och företag samt statistik över kommunernas befolknings- och näringslivsstruktur. Intervjuerna genomfördes under 2008. Resultaten visar ett tydligare mönster av mer traditionell arbetsdelning av hushållssysslorna bland Skåne- jämfört med Västerbottensparen. Samma mönster gäller även vid jämförelse mellan kommunerna med lågt respektive högt uttag. En mer positiv attityd till föräldraförsäkringen finns i kommunerna med högt föräldrapenninguttag bland fäder jämfört med de med lågt uttag. En förklaring kan vara att förändringar tenderar att uppträda först i heterogena miljöer med en relativt ung och välutbildad befolkning där olika normsystem konkurrerar med varandra, vilket gäller Umeå och Lund. I Västerbotten har Försäkringskassan, landstinget och företag haft kampanjer för män under 1990-talet vilket sannolikt har bidragit positivt till fäders uttag. Fäder i de bägge länen uttrycker positiva upplevelser av att ha varit föräldralediga. Ett dominerande intryck är att arbetsgivarna har en tillåtande attityd till fäders önskan om att vara föräldralediga.
|
|
| 13. |
|
|
| 14. |
- Almqvist, Anna-Lena, et al.
(författare)
-
Parental leave in Sweden : Motives, perceptions and gender equality among parents
- 2010
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper investigated Swedish parents’ motives for, experiences of and gender equality in relation to paid parental leave. The purpose was to explore similarities and differences in attitudes and experiences between parents in the two regions in Sweden with the largest difference in paid parental leave use among fathers. Data were drawn from interviews completed in 2008 with 16 heterosexual couples with a child born 2005 or 2006. The semi-structured interviews were analyzed according to grounded theory. In terms of experiences of the leave, a positive similarity in the study was that the couples described that they got to know the child better. Some negative similarities were that they felt they were alone and restricted. Primarily, the fathers in the northern part, focused on the lack of male networks. A traditional division of labor was a stronger pattern among couples in the southern region compared with the couples in the northern region. Tendencies are indicated towards an increased child-orientation, which could be connected with a change in hegemonic masculinity. In conclusion, the differences discovered between the four communities may to a great extent be depending on a cultural lag. This implied that change in values tend to take place first in social environments with multiple heterogeneous actors.
|
|
| 15. |
- Almqvist, Anna-Lena, et al.
(författare)
-
Parental leave in Sweden : Motives, experiences and gender equality among parents – focusing fathers
- 2010
-
Ingår i: XVII ISA World Congress of Sociology, Sociology on the Move. ; , s. 12-12
-
Konferensbidrag (refereegranskat)abstract
- The purpose was to explore similarities and differences in motives, experiences and gender equality between parents in two municipalities (one smaller than the other) in each of the two counties in Sweden with the largest difference in paid parental leave use among fathers. Data were drawn from interviews in 2008 with 16 heterosexual couples with a child born 2005 or 2006. The semi-structured interviews were analyzed inspired by grounded theory. A positive similarity was that couples experienced that they got to know the child better. Negative similarities were that mothers and fathers occasionally felt alone and restricted, fathers emphasized lack of male networks. Traditional division of household labor is a stronger pattern among couples in the southern county compared with couples in the northern county. Tendencies are towards increased child-orientation among fathers, which could connect to change in hegemonic masculinity, not necessarily related to increased gender equality in household labor. Differences may depend on that changes in values tend to first occur in heterogeneous social environments, such as the larger municipalities. In the northern county, extensive campaigns have been held during the 1990s to encourage men’s use of paid parental leave, which may have contributed to regional difference.
|
|
| 16. |
|
|
| 17. |
- Aspeborg, Henrik, 1970-, et al.
(författare)
-
Vegetabile material, plants and a method of producing a plant having altered lignin properties
- 2008
-
Patent (populärvet., debatt m.m.)abstract
- The present invention is related to a set of genes, which when modified in plants gives altered lignin properties. The invention provides DNA construct such as a vector useful in the method of the invention. Further, the invention relates to a plant cell or plant progeny of the plants and wood produced by the plants according to the invention Lower lignin levels will result in improved saccharification for bio-refining and ethanol production and improved pulp and paper. Increased lignin levels will utilise lignin properties for energy production. The genes and DNA constructs may be used for the identification of plants having altered lignin characteristics as compared to the wild-type. According to the invention genes and DNA constructs may also be used as candidate genes in marker assisted breeding.
|
|
| 18. |
|
|
| 19. |
- Bergquist, Annika, et al.
(författare)
-
Increased risk of primary sclerosing cholangitis and ulcerative colitis in first-degree relatives of patients with primary sclerosing cholangitis
- 2008
-
Ingår i: Clinical Gastroenterology and Hepatology. - New York : Elsevier. - 1542-3565 .- 1542-7714. ; 6:8, s. 939-943
-
Tidskriftsartikel (refereegranskat)abstract
- Background & Aims: The importance of genetic factors for the development of primary sclerosing cholangitis (PSC) is incompletely understood. This study assessed the risk of PSC and inflammatory bowel disease (IBD) among first-degree relatives of patients with PSC, compared with the first-degree relatives of a cohort without PSC. Methods: Subjects from the national Swedish cohort of PSC patients (n = 678) were matched for date of birth, sex, and region to up to 10 subjects without a diagnosis of PSC (n = 6347). Linkage through general population registers identified first-degree relatives of subjects in both the PSC and comparison cohorts (n = 34,092). Diagnoses among first-degree relatives were identified by using the Inpatient Register. Results: The risk of cholangitis was statistically significantly increased in offspring, siblings, and parents of the PSC patient cohort, compared with relatives of the comparison cohort, with the hazard ratios and 95% confidence intervals, 11.5 (1.6–84.4), 11.1 (3.3–37.8), and 2.3 (0.9–6.1), respectively. The hazard ratios for ulcerative colitis (UC) among first-degree relatives of all PSC patients was 3.3 (2.3–4.9) and for Crohn's disease 1.4 (0.8–2.5). The risk of UC for relatives of PSC patients without IBD was also increased, 7.4 (2.9–18.9). Conclusions: First-degree relatives of patients with PSC run an increased risk of PSC, indicating the importance of genetic factors in the etiology of PSC. First-degree relatives of PSC patients without IBD are also at an increased risk of UC, which might indicate shared genetic susceptibility factors for PSC and UC.
|
|
| 20. |
- Bjornsson, Einar, et al.
(författare)
-
Akut leversvikt - viktigt med snabb multidisciplinär handläggning
- 2007
-
Ingår i: Läkartidningen. - 0023-7205. ; 104:4, s. 210-213
-
Tidskriftsartikel (refereegranskat)abstract
- A recent study in Sweden on patients with acute liver failure (ALF) 1994-2003 demonstrated that the most common causes were paracetamol toxicity (42%) and idiosyncratic drug reactions (15%). In 11% of cases of ALF no definite etiology could be established. Among patients with paracetamol toxicity, the spontaneous survival without liver transplantation was 82% compared to 49% in patients with reactions to other drugs and 29% among the patients with indeterminate cause. Patients with ALF need a rapid and effective diagnostic work-up to detect the etiology as this often determines the outcome. In ALF it is of major importance to make an early contact with a transplant centre as the search for a suitable donor organ may take time in patients who are candidates for a liver transplantation. Patients with acute liver failure need a multidisciplinary care with co-operation between hepatologists, intensive care unit specialists and transplant surgeons.
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
- Björnsson, Einar, et al.
(författare)
-
Akut leversvikt - viktigt med snabb multidisciplinär handläggning : [Acute liver failure--rapid multidisciplinary management]
- 2007
-
Ingår i: Läkartidningen. - 0023-7205 .- 1652-7518. ; 104:4, s. 210-213
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- A recent study in Sweden on patients with acute liver failure (ALF) 1994-2003 demonstrated that the most common causes were paracetamol toxicity (42%) and idiosyncratic drug reactions (15%). In 11% of cases of ALF no definite etiology could be established. Among patients with paracetamol toxicity, the spontaneous survival without liver transplantation was 82% compared to 49% in patients with reactions to other drugs and 29% among the patients with indeterminate cause. Patients with ALF need a rapid and effective diagnostic work-up to detect the etiology as this often determines the outcome. In ALF it is of major importance to make an early contact with a transplant centre as the search for a suitable donor organ may take time in patients who are candidates for a liver transplantation. Patients with acute liver failure need a multidisciplinary care with co-operation between hepatologists, intensive care unit specialists and transplant surgeons.
|
|
| 24. |
|
|
| 25. |
|
|
| 26. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Basic knowledge of wood properties for improved performance of laminated Veneer products
- 2013
-
Ingår i: Pro Ligno. - Brasov : Publishing House of Transilvania University of Brasov. - 1841-4737 .- 2069-7430. ; 9:4, s. 549-556
-
Tidskriftsartikel (refereegranskat)abstract
- To ensure success in the production of laminated veneer products, it is necessary to acquire a sound basic understanding of the behaviour of the wood, and to understand the inherent reactions of wood to adhesive, heat, moisture, strain and stress. This can ensure an efficient wood utilization and promote the development of new processes and products that take advantage of the visco-elastic nature of wood. A shortcoming of the laminated bending process is that the products may become distorted after moulding and during use. In this study, we have examined how the performance of laminated veneer products can be improved through the implementation of basic knowledge of wood in the design and production process. The results show that the material and process parameters and storage in a changing relative humidity have a clear impact on distortion. Fibre orientation of the veneers in the moulded assembly was the most critical parameter to control. Fibre deviations mainly resulted in twist of the product. A moisture content in one veneer deviating from that of the rest of the veneers in the assembly before moulding resulted in distortion of the laminated veneer products both after moulding and during use. To decrease the negative effect of fibre orientation and moisture content on shape stability, the veneer should be straight-grained and well-conditioned to a moisture level adapted to the use of the final product. Special care should also be taken to orientate the veneers during assembly before moulding.
|
|
| 27. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Chipless Machining; Challanges in Manufacture of Laminated Veneer Products
- 2015
-
Ingår i: Proceedings of the 22nd International Wood Machining Seminar, IWMS 22.. - Qubec City : Universite Laval. - 9780994796400 - 9780994796400 ; , s. 155-164
-
Konferensbidrag (refereegranskat)abstract
- A laminated veneer product (LVP) consists of veneers bonded together with adhesive under pressure into a predetermined shape and, in general, under increased temperature to shorten the curing time of the adhesive. The process is commonly used in furniture design to manufacture complex forms such as thin shells. In the industrial production of LVP and when the ready- for-use components are exposed to climate variations, rejection due to distortion of the laminates is a major problem. The shape stability depends on a variety of material and process parameters, and this study has focused on the influence of fibre deviation in a single veneer. Recent research on the shape stability of LVP and how distortion is influenced by various material and production parameters is presented. A finite-element model for LVP is introduced and the use of this modelis exemplified by predicting the shape of a LVP with fibre distortion in a single veneer. The results show that it is possible to improve the shape stability of LVP if knowledge of various material and process parameters is implemented in the manufacturing process, and that a simulation based on a model of the wood material can be helpful in estimating the risk of an undesired deformation of the product.
|
|
| 28. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Contact free measurement of complex shapes in the wood industry
- 2011
-
Ingår i: Mechano-chemical transformations of wood during THM processing. - Biel, Switzerland : Bern University of Applied Sciencs, Architecture, Wood and Civil Engineering. - 9783952378700 ; , s. 143-144
-
Konferensbidrag (refereegranskat)abstract
- There is an increasing need to update and correct information about product geometry in the wood manufacturing industry. Changes in machinery or personnel can be the cause of that need. Manual measurement takes time and diff erent ways of digitizing the geometry of the products have therefore been developed.In this study, two methods (3D-coordinate measurement and optical scanning) have been tested together in order to determine the position of a product in relation to the processing machine, and to optically scan the product geometry. The aim was to identify and evaluate methods to digitize product geometry into a CAD-model for the wood industry. Th e seat shell measured was fitted in the CNC-machine where the processing later would be performed.The methodology used has made it possible to create a CAD-model from the physical model. Based on the experience from this methodology, it would be recommended to continue by creating of a tool that minimizes the need for after processing, i.e. the adjustment of certain coordinates manually.
|
|
| 29. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Distortion in laminated veneer products exposed to relative-humidity variations : Experimental studies and finite-element modelling
- 2019
-
Ingår i: BioResources. - Raleigh, NC : North Carolina State Univ Dept Wood & Paper Sci. - 1930-2126. ; 14:2, s. 3768-3779
-
Tidskriftsartikel (refereegranskat)abstract
- A shortcoming of the laminated bending process is that the product may become distorted after moulding. This study focused on the influence of fibre orientation deviation for individual veneers on the distortion of a moulded shell. The distortion of 90 cross-laminated shells of the same geometrical shape, consisting of seven peeled birch veneers, were studied under relative humidity variation. All the veneers were straight-grained in the longitudinal-tangential plane, but to simulate a deviation in fibre orientation, some of the individual veneers were oriented at an angle of 7° relative to the main orientation of the other veneers in the laminate. A finite element model (FEM) was applied to study the possibility of predicting the results of a practical experiment. The study confirms the well-known fact that deviation in fibre orientation influences shape stability. The results also show how the placement of the abnormal veneer influences the degree of distortion. From this basic knowledge, some improvements in the industrial production were suggested. However, the FE model significantly underestimated the results, according to the empirical experiment, and it did not show full coherence. The survey shows the complexity of modelling the behaviour of laminated veneer products under changing climate conditions and that there is a great need to improve the material and process data to achieve accurate simulations. Examples of such parameters that may lead to distortion are density, annual ring orientation in the cross section of the veneer, the orientation of the loose and tight sides of the veneer, and parameters related to the design of the moulding tool.
|
|
| 30. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Improving the performance of bended laminated veneer products
- 2011
-
Ingår i: Mechano-chemical transformations of wood during THM processing. - Biel, Switzerland : Bern University of Applied Sciencs, Architecture, Wood and Civil Engineering. - 9783952378700 ; , s. 147-148
-
Konferensbidrag (refereegranskat)abstract
- Laminated bending of veneers mean that dried, thin veneers or thin wood sheets are glued together under influence of pressure and eventually increased temperature. At the same time the product is given its desired shape, most often curved. This thermo hydro mechanical process offers several benefits. For example thick bends of small radiuses of any species of wood may be formed and poor quality wood containing knots, splits and other defects may be utilised. Laminated bends can usually be set more readily and made to conform better to the shape of the form than similar bends of solid wood. Further no softening treatment is generally required before the pieces are bent. However, there are also disadvantages e.g. more technical skill and better equipment are usually required than for solid wood bending. The presence of glue may be somewhat detrimental to the machines used for the final cleaning up of the bent pieces. Further the glue lines which are usually visible on the sides may be an aesthetical unappreciated effect [1],[2].The quality of the laminated bended veneer products are obtained as an interaction between the process, the veneers and the glue [3]. In industries designing and producing these products it is of interest to obtain better understanding of how processing- and material parameters affect the product quality. With an improved understanding of the material and processing parameters it may be possible to increase the efficiency of wood utilisation and promote the development of new processes and products that manipulate the viscoelastic nature of wood. In particular the possibilities to obtain narrower radius of curvature and better possibilities of bending in more than one plane would be advantageous.This study has focused on the moisture content (MC) and the grain angle orientation in the veneers. These two specific aspects were assumed to have a great influence on spring-back and distortions of the laminated bended veneer products. Spring-back and distortions were therefore studied in separate tests where MC and the grain angle orientation was varied separately in manufactured laminated bended wood products. After manufacturing the products were exposed to variations in humidity and temperature whereupon the spring-back and distortions were measuredThree tests were performed. For the first and the second test a seat shell was selected as test product, figure 1a. To the third test another product was selected, figure 1b. This product was a small bookshelf. The company producing this shelf had experienced large problems considering distortions of this product. Further the product was very simple in shape with only one bend and therefore suitable for measurements.In the first test the influence of MC of the veneers was investigated. In the second and third test the influence of grain angle of the veneers was studied.For the study veneers of birch and beech were selected in the production. For the first and third study only birch veneers were used. The veneers were initially conditioned to equilibrium moisture contents (EMC) according to setups in different test groups. For the first study a test group was also built up from veneers taken directly out of production to study the industrial conditions. The seat shells in this test group contained veneers conditioned to EMC 4 %, except for the surface veneers that had been stored in the production hall. The humidity and temperature conditions in this room corresponded to MC 7 %.The manufacturing of the products were performed in industrial conditions. In the tests the products were built up from a number of veneers and the studied factors were varied between the veneers in a controlled manner.The results from the first test showed that the MC of the veneers influenced the spring-back and the distortions. A large moisture gradient between veneers and especially unsymmetrical placements of these in the construction were especially critical. The results from the second and third tests showed that grain angle deviation has large effect on the distortions of the products. Even a small grain angle deviation as in study two (5°) resulted in large problems with distortions. The study also showed that when crossing two or more veneers with deviating grain angles there were cases when these faults interacted and multiplied the distortions. In production grain angle deviations can be a result of inaccurate placement of the veneers during pressing, incorrect cutting of the veneers, inherent from the growth of the tree or a combination of these factors. Deviations of the grain angle were, however, shown to have only small effects on spring-back.
|
|
| 31. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Influence of veneer orientation on shape stability of plane laminated veneer products
- 2014
-
Ingår i: Wood Material Science & Engineering. - : Informa UK Limited. - 1748-0272 .- 1748-0280. ; 9:4, s. 224-232
-
Tidskriftsartikel (refereegranskat)abstract
- One of the most important quality aspects of a laminated veneer product is its shape stability under changing relative humidity (RH). This study aimed to establish an understanding of how the orientation of individual veneers in the laminate, i.e., orientation according to fibre orientation and orientation of the loose (the side with ‘lathe checks’) or tight side of the veneer, affects the shape stability. Three-ply laminates from peeled veneers of beech (Fagus sylvatica L.) were studied. The four types of laminate were the following: loose sides of all veneers in the same direction (cross and parallel centre ply) and loose sides of the outer veneers facing inward (cross and parallel centre ply). Four replicates of each type yielded 16 samples. The samples were exposed to RH cycling at 20% and 85% RH at 20°C, and the shapes of the samples were determined. The shape stability was influenced by the veneer orientation. Laminations with the middle veneer perpendicular to the top and bottom veneer (cross-laminated) showed the best shape stability, especially when the loose sides of the veneers were oriented the same direction. In parallel-laminated veneers, the laminates with opposite directions of the loose sides in the two outermost veneers showed the best shape stability. The major explanation of the behaviour of the laminates is that the loose side expanded more than the tight side from the dry to the humid climate, which was shown by optical 3D deformation analysis (ARAMISTM). After RH cycling, the laminates with cross plies showed visible surface checks only when the tight side was facing outwards.
|
|
| 32. |
- Blomqvist, Lars, 1962-
(författare)
-
Laminated Veneer Products : Shape Stability and Effect of Enhanced Formability on Bond-Line Strength
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis concerns two aspects of the manufacture of laminated veneer products (LVPs). The first aspect is related to the possible improvement of the shape stability of LVPs, and the second has its starting point in the modification of the veneer for enhanced formability as well as the question of whether and how these modifications affect the bond-line strength.LVPs are veneers bonded with adhesive into predetermined shapes, mostly for the production of furniture and interior fittings. Since any deviation from the intended shape is a problem for both manufacturer and customer, various studies have sought to evaluate the influence of different materials and process parameters on shape stability. Parameters studied have included wood species (beech and birch), an adhesive system based on urea formaldehyde, the adhesive distribution on the veneer, climate, moisture content and fibre orientations of the veneers, as well as the orientation of the individual veneers in a multiply.Manufacturers of LVPs must consider some basic facts about wood in orders adequately to provide shape-stable LVPs to customers. Wood emits and absorbs moisture in relation to the surrounding climate, and this can lead to shrinkage and swelling. Such moisture induced movements differ in the wood’s different directions, and the magnitude is specific for the species. A thorough understanding of this is the basis for achieving shape-stable LVPs.Symmetry is defined in this thesis such that the veneer properties are balanced in the laminate. This means that opposite veneers on either side of the centre veneer have similar characteristic. An LVP will become distorted if the veneers are asymmetrically oriented before the press. Deviation from the desired shape can be small immediately after the pressing, but it may increase significantly with moisture content (MC) variations. Asymmetry may result when veneers with different fibre orientations are included in the laminate or when the veneers are placed asymmetrically. It may also occur if veneers with different MCs are bonded together asymmetrically. One aggravating factor is that the lathe checks that are introduced when the veneers are peeled or sliced from the log affect the shape stability. In 3-ply crosswise-oriented plywood, the veneer surfaces on which the lathe checks occur should be oriented in the same way for high shape stability.Based on existing knowledge, the production of shape-stable LVPs requires that the veneers are conditioned to a uniform MC and sorted with regard to fibre orientation and the side with lathe checks before bonding. End-user climates should govern the MC of the veneers and the moisture added with the adhesive during the process. Straight-grain veneers and symmetry should always be the goal.Moulding can cause stretching, i.e. strain, of the veneers depending on the curvature of the mould. To prevent the veneers from rupture, there are various ways to strengthen the veneers particularly in the transverse direction in which the veneer is weakest. However, tests have shown that these pre-treatments of veneers for enhanced formability can prevent the adhesive from penetrating the wood surface. It is therefore important to confirm that the pre-treatment does not affect the bond-line strength.
|
|
| 33. |
|
|
| 34. |
|
|
| 35. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Moisture-induced distortion of laminated veneer products
- 2013
-
Ingår i: Proceedings of the 9<sup>th</sup> meeting of the Northern European network for wood science and engineering (WSE). - Hannover, Germany. ; , s. 178-183
-
Konferensbidrag (refereegranskat)abstract
- Laminated veneer products consist of veneers bonded together with adhesive into a predetermined shape. Since wood is a hygroscopic material and also anisotropic by nature, laminated veneer products are especially shape-sensitive to changes in moisture content. A deviation from the intended shape is a problem for both the manufacturers and users of the final products and annually such deviations cause great economic losses in the manufacturing industry. To illustrate the influence of moisture on distortion and shape stability, studies have been performed in industrial conditions and in a laboratory environment. Veneers of beech and birch and a seat shell moulded from these veneers were used in the study. Distortion, i.e. spring-back, position and twist, has been determined directly after moulding and during subsequent moisture and drying cycles. The distortion follows more or less slavishly the changes in relative humidity around the product. The distortion is generally small directly after moulding but, after the laminates have been exposed to a variation in relative humidity, the distortion increases. Some of the problems of poor shape stability that may arise later in the bending process can be reduced if attention is paid to moisture content and fibre orientation already in the production of the veneer. To achieve good shape stability of laminated veneer products in practice, the following should be followed by the manufacture industry:develop cooperation with suppliers of veneer and set requirements of veneer with regard to deviation of the fibre orientation, and require that the veneer be dried and conditioned to a moisture content consistent with production,control incoming veneers with respect to fibre orientation and moisture content,plan warehousing of veneers and ensure adequate conditioning, andconsider the orientation of the veneers and the species.
|
|
| 36. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Shape stability of laminated veneer products : How to decrease the negative effects of fibre deviation?
- 2013
-
Ingår i: Forest Products Society (FPS) 67th International Convention. - Madison : Forest Products Society.
-
Konferensbidrag (refereegranskat)abstract
- A shortcoming of the laminated bending process is that the products may become distorted after moulding and during use. Annually, significant financial losses have incurred in the furniture and interior design industries as a result of distorted products. In this study, we have examined the influence of deviation of fibre orientation of individual veneers on distortion of a moulded shell to find ways to improve shape stability of laminated veneer products.Ninety cross-laminated shells, consisting of 7 veneers of Birch (Betula pubescens Ehrh.) with a total thickness of 3.6 mm, were studied. The in-plane dimensions of the veneer were 400x660 mm. All the veneers were straight-grained, but to simulate deviation in fibre orientation some of the individual veneers were oriented 7 degrees relative to the main orientation of the other veneers in the laminate. Distortion was determined directly after moulding and after storage in a changing relative humidity.The results show the well-known fact that deviation of fibre orientation of the veneers in the laminate influences the shape stability of the product. The results from this study, however, also show how the placement of the abnormal veneers in the laminated veneer products influences the degree of distortions. From this basic knowledge some improvements for production of laminated veneer products were suggested.
|
|
| 37. |
- Blomqvist, Lars, 1962-
(författare)
-
Shape stability of laminated veneer products
- 2013
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is about the shape stability of laminated veneer products.Laminated veneer products consist of veneers bonded together with adhesive into a predetermined shape. Such products are used in several contexts but especially in furniture manufacture. Deviation from the intended shape is a problem for both manufacturers and customers of the final products. The shape stability of laminated veneer products depends on a variety of material and process parameters, and this thesis identifies several important factors that influence shape stability. The purpose of this thesis is to find ways to decrease distortion and improve shape stability so that product quality can be improved.Different ways of measuring shape stability, both in an industrial environment and in a more research-based context, are presented in this thesis. Various studies have been conducted to evaluate the influence of different material and process parameters on shape stability. The parameters studied were species (beech and birch), adhesive system (bio-based adhesives, adhesive systems based on urea formaldehyde), adhesive distribution on the veneer, climate, moisture content and fibre orientations of the veneers, as well as orientation of the individual veneers in an assembly.The results clearly show that the fibre orientation of the veneer strongly influences the shape stability of a laminated veneer product. This means that products can show considerable distortion (particularly twist) if the fibre orientation of the veneer is orientated in an unsuitable way in the assembly before moulding. The effect of fibre orientation on shape stability can be very small directly after moulding, but it increases considerably when the moulded product is subjected to a change in moisture content. In general, a change in moisture content leads to distortion. Moisture change alone, however, results in a controlled distortion.An asymmetrical construction coupled with different moisture contents of the veneers in an assembly before moulding will result in poor shape stability of the product. Other studied parameters had a low impact on shape stability, although beech resulted in more distortion and poorer shape stability than birch.In order to produce shape-stable laminated veneer products, the veneers should be conditioned to a uniform moisture content and sorted with regard to fibre orientation before bonding. The orientation of the veneers is highly important regarding both fibre orientation and the loose or tight side of the veneer. If shape stability is the main target, the loose sides of peeled and sliced veneers should be oriented in the same manner.
|
|
| 38. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
Shape stability of laminated veneer products : an experimental study of the influence on distortion of some material and process parameters
- 2013
-
Ingår i: Wood Material Science & Engineering. - : Taylor & Francis Group. - 1748-0272 .- 1748-0280. ; 8:3, s. 198-211
-
Tidskriftsartikel (refereegranskat)abstract
- Laminated bending of veneers is a common used and important process for manufacture of components primarily for furniture and interior purposes. According to the use, such products are in general very sensitive to variations in the intended shape, i.e. distortion can be of great problem and more or less destroy the use of the final product. The most critical mode of distortion is twist, but also other changes in shape may be of interest to keep low. The causes to distortion of laminated bended veneer products can be of material (veneer, adhesive and the combination of these), design, processes and climate nature and there is a challenge to know which parameters which are of major importance for distortion, both directly after moulding and when the products are in use.In this study, the influence of type of UF-adhesive hardener, i.e. liquid or powder, water content of adhesive, adhesive distribution, variation of moisture content of glued veneers, and fibre orientation of veneers, on twist and position for a 3D-veneer construction (a chair seat shell) has been studied. Distortion, i.e. twist and position, has been determined directly after moulding and after moisture cycling. The moisture cycling was to simulate and accelerate conditions that the shells are subjected in use. The aim of the work is to study how the above mentioned material and process parameters influence the shape stability of the products.The results show that the climate, i.e. how a certain level of temperature and relative humidity influence the moisture content of the moulded product, has a clear impact on the distortion of the product in use. An increase in moisture content results in a significant increase in distortion and vice versa. The level to which the moulded products distort during climate variation can be controlled through controlling material, design and process parameter during moulding. Of the studied parameter mentioned above, a deviation in fibre orientation of the veneers in the moulded assembly is the most critical parameter to have under control to minimize distortion. The fibre deviation mainly results in an increase in twist. A high moisture content of a veneer vis-à-vis the rest of the veneers in the assembly before moulding, will result in increased position and twist of the moulded product in use. The difference of moisture content between veneers and the position of veneers with high moisture content in the assembly will influence the level of distortion. Other studied parameter also influences the distortion to a lesser extent and can in these cases be related to the moisture distribution in the mouldings.
|
|
| 39. |
|
|
| 40. |
- Blomqvist, Lars, et al.
(författare)
-
The effect of veneer-modifcation on the bond-strength in laminated veneer products
- 2015
-
Ingår i: Pro Ligno. - 1841-4737 .- 2069-7430. ; 11:4, s. 43-49
-
Tidskriftsartikel (refereegranskat)abstract
- A major problem in the manufacture of three-dimensional laminated veneer products (LVP) is damage due to stretching and/or buckling of the veneer. To reduce or eliminate this problem, veneer densification or adding a strengthening layer to the veneer can be an alternative. To study how veneer modification influences the veneer-to-adhesive bond strength, three methods of modification were studied in relation to an unmodified reference veneer: (1) densified veneer, (2) veneer pre-bonded with paper and hot melt adhesive (HMA), (3) veneer pre-bonded with non-woven polypropylene (NW) fabric glued to the veneer (a) with a urea formaldehyde (UF) adhesive, (b) with a mixture of UF and polyvinyl acetate (PVAc) adhesive, and (c) with a PVAc adhesive. Densification, pre-bonding with paper, and NW with UF/PVAc adhesive mixture resulted in no or only a slight decrease in strength of the bond-line compared to the reference. NW glued with UF or PVAc adhesive showed a considerable reduction in the strength of the bond-line. The climatic cycling had no significant influence on the bond strength.
|
|
| 41. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
The effect of veneer modification on the bond-line strength in laminated veneer products
- 2015
-
Ingår i: Pro Ligno. - Brasov, Romania : Transilvania University. - 1841-4737 .- 2069-7430. ; 11:4, s. 43-49
-
Tidskriftsartikel (refereegranskat)abstract
- A major problem in the manufacture of three-dimensional laminated veneer products (LVP) is damage due to stretching and/or buckling of the veneer. To reduce or eliminate this problem, veneer densification or adding a strengthening layer to the veneer can be an alternative. To study how veneer modification influences the veneer-to-adhesive bond strength, three methods of modification were studied in relation to an unmodified reference veneer: (1) densified veneer, (2) veneer pre-bonded with paper and hot melt adhesive (HMA), (3) veneer pre-bonded with non-woven polypropylene (NW) fabric glued to the veneer (a) with a urea formaldehyde (UF) adhesive, (b) with a mixture of UF and polyvinyl acetate (PVAc) adhesive, and (c) with a PVAc adhesive. Densification, pre-bonding with paper, and NW with UF/PVAc adhesive mixture resulted in no or only a slight decrease in strength of the bond-line compared to the reference. NW glued with UF or PVAc adhesive showed a considerable reduction in the strength of the bond-line. The climatic cycling had no significant influence on the bond strength.
|
|
| 42. |
|
|
| 43. |
- Blomqvist, Lars, 1962-, et al.
(författare)
-
The influence of veneer modification on adhesive bond strength
- 2014
-
Ingår i: Proceedings of 10th Meeting of the Northern European Network for Wood Science & Engineering (WSE). - Edinburgh : Edinburgh Napier University.. ; , s. 150-155
-
Konferensbidrag (refereegranskat)
|
|
| 44. |
|
|
| 45. |
- Bonagas, Nadilly, et al.
(författare)
-
Pharmacological targeting of MTHFD2 suppresses acute myeloid leukemia by inducing thymidine depletion and replication stress
- 2022
-
Ingår i: NATURE CANCER. - : Springer Science and Business Media LLC. - 2662-1347. ; 3:2, s. 156-
-
Tidskriftsartikel (refereegranskat)abstract
- The folate metabolism enzyme MTHFD2 (methylenetetrahydrofolate dehydrogenase/cyclohydrolase) is consistently overexpressed in cancer but its roles are not fully characterized, and current candidate inhibitors have limited potency for clinical development. In the present study, we demonstrate a role for MTHFD2 in DNA replication and genomic stability in cancer cells, and perform a drug screen to identify potent and selective nanomolar MTHFD2 inhibitors; protein cocrystal structures demonstrated binding to the active site of MTHFD2 and target engagement. MTHFD2 inhibitors reduced replication fork speed and induced replication stress followed by S-phase arrest and apoptosis of acute myeloid leukemia cells in vitro and in vivo, with a therapeutic window spanning four orders of magnitude compared with nontumorigenic cells. Mechanistically, MTHFD2 inhibitors prevented thymidine production leading to misincorporation of uracil into DNA and replication stress. Overall, these results demonstrate a functional link between MTHFD2-dependent cancer metabolism and replication stress that can be exploited therapeutically with this new class of inhibitors. Helleday and colleagues describe a nanomolar MTHFD2 inhibitor that causes replication stress and DNA damage accumulation in cancer cells via thymidine depletion, demonstrating a potential therapeutic strategy in AML tumors in vivo.
|
|
| 46. |
- Bosaeus, Marja, et al.
(författare)
-
A randomized longitudinal dietary intervention study during pregnancy: effects on fish intake, phospholipids, and body composition
- 2015
-
Ingår i: Nutrition Journal. - : Springer Science and Business Media LLC. - 1475-2891. ; 14:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background Fish and meat intake may affect gestational weight gain, body composition and serum fatty acids. We aimed to determine whether a longitudinal dietary intervention during pregnancy could increase fish intake, affect serum phospholipid fatty acids, gestational weight gain and body composition changes during pregnancy in women of normal weight participating in the Pregnancy Obesity Nutrition and Child Health study. A second aim was to study possible effects in early pregnancy of fish intake and meat intake, respectively, on serum phospholipid fatty acids, gestational weight gain, and body composition changes during pregnancy. Methods In this prospective, randomized controlled study, women were allocated to a control group or to a dietary counseling group that focused on increasing fish intake. Fat mass and fat-free mass were measured by air-displacement plethysmography. Reported intake of fish and meat was collected from a baseline population and from a subgroup of women who participated in each trimester of their pregnancies. Serum levels of phospholipid arachidonic acid (s-ARA), eicosapentaenoic acid (s-EPA), and docosahexaenoic acid (s-DHA) were measured during each trimester. Results Weekly fish intake increased only in the intervention group (n=18) from the first to the second trimester (median difference 113 g, p=0.03) and from the first to the third trimester (median difference 75 g, p=0.01). In the first trimester, fish intake correlated with s-EPA (r=0.36, p=0.002, n=69) and s-DHA (r=0.34, p=0.005, n=69), and meat intake correlated with s-ARA (r=0.28, p=0.02, n=69). Fat-free mass gain correlated with reported meat intake in the first trimester (r=0.39, p=0.01, n=45). Conclusions Dietary counseling throughout pregnancy could help women increase their fish intake. Intake of meat in early pregnancy may increase the gain in fat-free mass during pregnancy.
|
|
| 47. |
- Bratt, Ola, et al.
(författare)
-
The Study of Active Monitoring in Sweden (SAMS) : A randomized study comparing two different follow-up schedules for active surveillance of low-risk prostate cancer
- 2013
-
Ingår i: Scandinavian Journal of Urology. - : Medical Journals Sweden AB. - 2168-1805 .- 2168-1813. ; 47:5, s. 347-355
-
Forskningsöversikt (refereegranskat)abstract
- Objective. Only a minority of patients with low-risk prostate cancer needs treatment, but the methods for optimal selection of patients for treatment are not established. This article describes the Study of Active Monitoring in Sweden (SAMS), which aims to improve those methods. Material and methods. SAMS is a prospective, multicentre study of active surveillance for low-risk prostate cancer. It consists of a randomized part comparing standard rebiopsy and follow-up with an extensive initial rebiopsy coupled with less intensive follow-up and no further scheduled biopsies (SAMS-FU), as well as an observational part (SAMS-ObsQoL). Quality of life is assessed with questionnaires and compared with patients receiving primary curative treatment. SAMS-FU is planned to randomize 500 patients and SAMS-ObsQoL to include at least 500 patients during 5 years. The primary endpoint is conversion to active treatment. The secondary endpoints include symptoms, distant metastases and mortality. All patients will be followed for 10-15 years. Results. Inclusion started in October 2011. In March 2013, 148 patients were included at 13 Swedish urological centres. Conclusions. It is hoped that the results of SAMS will contribute to fewer patients with indolent, low-risk prostate cancer receiving unnecessary treatment and more patients on active surveillance who need treatment receiving it when the disease is still curable. The less intensive investigational follow-up in the SAMS-FU trial would reduce the healthcare resources allocated to this large group of patients if it replaced the present standard schedule.
|
|
| 48. |
- Bridel, Claire, et al.
(författare)
-
Diagnostic Value of Cerebrospinal Fluid Neurofilament Light Protein in Neurology : A Systematic Review and Meta-analysis
- 2019
-
Ingår i: JAMA Neurology. - : American Medical Association (AMA). - 2168-6149 .- 2168-6157. ; 76:9, s. 1035-1048
-
Forskningsöversikt (refereegranskat)abstract
- Importance Neurofilament light protein (NfL) is elevated in cerebrospinal fluid (CSF) of a number of neurological conditions compared with healthy controls (HC) and is a candidate biomarker for neuroaxonal damage. The influence of age and sex is largely unknown, and levels across neurological disorders have not been compared systematically to date.Objectives To assess the associations of age, sex, and diagnosis with NfL in CSF (cNfL) and to evaluate its potential in discriminating clinically similar conditions.Data Sources PubMed was searched for studies published between January 1, 2006, and January 1, 2016, reporting cNfL levels (using the search terms neurofilament light and cerebrospinal fluid) in neurological or psychiatric conditions and/or in HC.Study Selection Studies reporting NfL levels measured in lumbar CSF using a commercially available immunoassay, as well as age and sex.Data Extraction and Synthesis Individual-level data were requested from study authors. Generalized linear mixed-effects models were used to estimate the fixed effects of age, sex, and diagnosis on log-transformed NfL levels, with cohort of origin modeled as a random intercept.Main Outcome and Measure The cNfL levels adjusted for age and sex across diagnoses.Results Data were collected for 10 059 individuals (mean [SD] age, 59.7 [18.8] years; 54.1% female). Thirty-five diagnoses were identified, including inflammatory diseases of the central nervous system (n = 2795), dementias and predementia stages (n = 4284), parkinsonian disorders (n = 984), and HC (n = 1332). The cNfL was elevated compared with HC in a majority of neurological conditions studied. Highest levels were observed in cognitively impaired HIV-positive individuals (iHIV), amyotrophic lateral sclerosis, frontotemporal dementia (FTD), and Huntington disease. In 33.3% of diagnoses, including HC, multiple sclerosis, Alzheimer disease (AD), and Parkinson disease (PD), cNfL was higher in men than women. The cNfL increased with age in HC and a majority of neurological conditions, although the association was strongest in HC. The cNfL overlapped in most clinically similar diagnoses except for FTD and iHIV, which segregated from other dementias, and PD, which segregated from atypical parkinsonian syndromes.Conclusions and Relevance These data support the use of cNfL as a biomarker of neuroaxonal damage and indicate that age-specific and sex-specific (and in some cases disease-specific) reference values may be needed. The cNfL has potential to assist the differentiation of FTD from AD and PD from atypical parkinsonian syndromes.
|
|
| 49. |
|
|
| 50. |
- Couceiro, José, 1983-, et al.
(författare)
-
CT scanning of capillary phenomena in bio-based materials
- 2017
-
Ingår i: Pro Ligno. - Romania : Pro Ligno Foundation. - 1841-4737 .- 2069-7430. ; 13:4, s. 181-187
-
Tidskriftsartikel (refereegranskat)abstract
- X-ray computed tomography (CT) is a powerful tool for the non-destructive study of dynamic moisture processes in wood and other bio-based materials. In the CT facilities at Luleå University of Technology, it is possible to study wood-moisture relations such as water absorption, drying and related material deformation under a temperature- and humidity-controlled environment.An increase in the use of bio-based materials in building construction has led to an increased interest in capillary phenomena in these materials, because of an increasing number of moisture-related damage in timber and hybrid-timber buildings. This article shows some examples of how different bio-materials used in construction interact with liquid water over time. The overall purpose has been to develop the CT technique as a powerful tool for the determination and visualization of capillary flow that can be a base for modelling and an increased understanding of moisture flow in new bio-based building materials.Early-stage observation of the behaviour of different traditional and new bio-based building materials shows that CT scanning, combined with image processing, has a high potential to be used in performing non-destructive and non-contact tests that can help to increase the knowledge of water-material interactions and develop building materials with an optimized performance.
|
|
