| 1. |
- Ahlqvist, Margary, et al.
(författare)
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A new reliable tool (PVC assess) for assessment of peripheral venous catheters
- 2010
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Ingår i: Journal of Evaluation In Clinical Practice. - : Wiley. - 1356-1294 .- 1365-2753. ; 16:6, s. 1108-1115
-
Tidskriftsartikel (refereegranskat)abstract
- Rationale and aims To evaluate the extensive use of peripheral venous catheters (PVCs), including catheter-related complications, a reliable tool for PVC assessment is needed. The aim of this study was to develop such a tool to evaluate PVCs in relation to management, documentation and signs and symptoms of thrombophlebitis (TH), as well as to determine its inter-rater and test-retest reliability. Method The tool development included confirmation of content and face validity. Two groups of registered nurses used the new tool (PVC assess) to assess PVC management and signs of TH independently. Group A (n = 3) assessed 26 items in 67 PVCs bedside (inter-rater reliability). Group B (n = 3) assessed photographs (67 PVCs, 21 items) of the same PVCs as those in Group A with a 4-week interval (test-retest reliability). Proportion of agreement P(A) and Cohen's kappa were calculated to evaluate inter-rater and test-retest reliability. Results Among nurses assessing PVCs at bedside, the P(A) was good to excellent (0.80-1) in 96% of the items in PVC assess. In 80% of the items kappa was substantial to almost perfect (0.61-1). TH sign erythema fell into the fair range (kappa = 0.40). In test-retest reliability analysis the P(A) was within the good and excellent range (0.80-1.0) and kappa varied from moderate to almost perfect (0.41-1.0) in 95% of the items. One item 'outer dressing is clean' was in fair range (0.21-0.40). Conclusions The PVC assess instrument shows satisfactory inter-rater and test-retest reliability. Reliability tests on reviewing documentation remain to be performed.
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| 2. |
- Ahrné, Karin, et al.
(författare)
-
Tillstånd och trender för arter och deras livsmiljöer – rödlistade arter i Sverige 2015
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- 2015 års upplaga av den svenska rödlistan är den fjärde i ordningen. Den är baserad på IUCN:s rödlistningskriterier och revideras vart femte år. I rödlistan bedöms risken som enskilda arter av djur, växter och svampar löper att försvinna från Sverige. Bedömningen utförs av ArtDatabankens medarbetare i samverkan med över 100 externa experter, indelade i 14 expertkommittéer för olika organismgrupper. Under arbetet med 2015 års rödlista har tillstånd och trender bedömts för 21 600 arter och 1 318 lägre taxa (apomiktiska arter, underarter och varieteter), sammanlagt ca 22 900 taxa. Av de bedömda arterna klassificerades 2 029 som hotade (kategorierna CR, EN och VU) och 4 273 som rödlistade (inkluderar även kategorierna NT, RE och DD). Förhållandet mellan antalet rödlistade och antalet bedömda arter ar 19,8 %, vilket är ungefär samma värde som 2010 och 2005. I denna rapport jämförs antalet och andelen rödlistade arter mellan olika organismgrupper, biotoper, substrat och påverkansfaktorer. Texten ar indelad i en allmän del och åtta kapitel inriktade på olika landskapstyper. Landskapstyperna utgör en grov indelning av landets miljöer enligt följande kategorier: Skog, Jordbrukslandskap, Urbana miljöer, Fjäll, Våtmarker, Sötvatten, Havsstränder och Havsmiljöer. Skogen och jordbrukslandskapet är de artrikaste landskapstyperna med 1 800 respektive 1 400 arter som har en stark anknytning dit, och ytterligare flera hundra arter som förekommer där mer sporadiskt. De faktorer som påverkar flest rödlistade arter i Sverige är skogsavverkning och igenväxning, som båda utgör ett hot mot vardera ca 30 % av de rödlistade arterna. Avverkning minskar arealen av skog där naturliga strukturer och naturlig dynamik upprätthålls, och den orsakar därmed förlust av livsmiljöer. Igenväxning orsakas av ett antal faktorer, bland annat upphörande hävd (bete och slåtter), gödsling, trädplantering och brist på naturliga störningsregimer som t.ex. regelbundna översvämningar kring vattendrag och sjöar. Andra viktiga påverkansfaktorer är fiske, torrläggning av våtmarker, tillbakagång hos värdarter (främst alm och ask som drabbats av invasiva svampsjukdomar), klimatförändringar och konkurrens från invasiva arter. IUCN:s rödlisteindex beräknas för ett urval av de bedömda organismgrupperna. Rödlisteindex visar att skillnaderna mellan rödlistorna från 2000, 2005, 2010 och 2015 är små. Ett par undantag finns dock. Groddjur och stora däggdjur har fått en något förbättrad situation sedan 2000. Totalt förefaller det ändå som att trycket mot Sveriges artstock har förblivit relativt konstant under de senaste 15 åren.
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| 3. |
- Andersson, Daniel P., et al.
(författare)
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Omentectomy in addition to gastric bypass surgery and influence on insulin sensitivity : A randomized double blind controlled trial
- 2014
-
Ingår i: Clinical Nutrition. - : Elsevier BV. - 0261-5614 .- 1532-1983. ; 33:6, s. 991-996
-
Tidskriftsartikel (refereegranskat)abstract
- Background & aims: Accumulation of visceral adipose tissue is associated with insulin resistance and cardio-vascular disease. The aim of this study was to elucidate whether removal of a large amount of visceral fat by omentectomy in conjunction with Roux en-Y gastric bypass operation (RYGB) results in enhanced improvement of insulin sensitivity compared to gastric bypass surgery alone. Methods: Eighty-one obese women scheduled for RYGB were included in the study. They were randomized to RYGB or RYGB in conjunction with omentectomy. Insulin sensitivity was measured by hyperinsulinemic euglycemic clamp before operation and sixty-two women were also reexamined 2 years post-operatively. The primary outcome measure was insulin sensitivity and secondary outcome measures included cardio-metabolic risk factors. Results: Two-year weight loss was profound but unaffected by omentectomy. Before intervention, there were no clinical or metabolic differences between the two groups. The difference in primary outcome measure, insulin sensitivity, was not significant between the non-omentectomy (6.7 +/- 1.6 mg/kg body weight/minute) and omentectomy groups (6.6 +/- 1.5 mg/kg body weight/minute) after 2 years. Nor did any of the cardio-metabolic risk factors that were secondary outcome measures differ significantly. Conclusion: Addition of omentectomy to gastric bypass operation does not give an incremental effect on long term insulin sensitivity or cardio-metabolic risk factors. The clinical usefulness of omentectomy in addition to gastric bypass operation is highly questionable.
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| 4. |
- Andersson, Richard L., et al.
(författare)
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Micromechanical Tensile Testing of Cellulose-Reinforced Electrospun Fibers Using a Template Transfer Method (TTM)
- 2012
-
Ingår i: Journal of Polymers and the Environment. - : Springer Science and Business Media LLC. - 1566-2543 .- 1572-8919 .- 1572-8900. ; 20:4, s. 967-975
-
Tidskriftsartikel (refereegranskat)abstract
- A template transfer method (TTM) and a fiber fixation technique were established for fiber handling and micro tensile stage mounting of aligned and non-aligned electrospun fiber mats. The custom-made template had been precut to be mounted on a variety of collectors, including a rapidly rotating collector used to align the fibers. The method eliminated need for direct physical interaction with the fiber mats before or during the tensile testing since the fiber mats were never directly clamped or removed from the original substrate. By using the TTM it was possible to measure the tensile properties of aligned poly(methyl methacrylate) (PMMA) fiber mats, which showed a 250 % increase in strength and 450 % increase in modulus as compared to a non-aligned system. The method was further evaluated for aligned PMMA fibers reinforced with cellulose (4 wt%) prepared as enzymatically derived nanofibrillated cellulose (NFC). These fibers showed an additional increase of 30 % in both tensile strength and modulus, resulting in a toughness increase of 25 %. The fracture interfaces of the PMMA-NFC fibers showed a low amount of NFC pull-outs, indicating favorable phase compatibility. The presented fiber handling technique is universal and may be applied where conservative estimates of mechanical properties need to be assessed for very thin fibers.
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| 5. |
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| 6. |
- Ansari, Farhan, et al.
(författare)
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Nanostructured biocomposites based on unsaturated polyester resin and a cellulose nanofiber network
- 2015
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Ingår i: Composites Science And Technology. - : Pergamon Press. - 0266-3538 .- 1879-1050. ; 117, s. 298-306
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Tidskriftsartikel (refereegranskat)abstract
- Biocomposites reinforced by natural plant fibers tend to be brittle, moisture sensitive and have limited strength. Wood cellulose nanofibers (CNF) were therefore used to reinforce an unsaturated polyester matrix (UP) without the need of coupling agents or CNF surface modification. The nanostructured CNF network reinforcement strongly improves modulus and strength of UP but also ductility and toughness. A template-based prepreg processing approach of industrial potential is adopted, which combines high CNF content (up to 45 vol%) with nanoscale CNF dispersion. The CNF/UP composites are subjected to moisture sorption, dynamic thermal analysis, tensile tests at different humidities, fracture toughness tests and fractography. The glass transition temperature (T-g) increases substantially with CNF content. Modulus and strength of UP increase about 3 times at 45 vol% CNF whereas ductility and apparent fracture toughness are doubled. Tensile properties at high humidity are compared with other bio-composites and interpreted based on differences in molecular interactions at the interface.
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| 7. |
- Bennet, Louise, et al.
(författare)
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Clinical appearance of erythema migrans caused by Borrelia afzelii and Borrelia garinii : effect of the patient´s sex
- 2006
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Ingår i: Wiener Klinische Wochenschrift. - : SPRINGER WIEN. - 0043-5325 .- 1613-7671. ; 118:17-18, s. 531-537
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Tidskriftsartikel (refereegranskat)abstract
- Aim: The aim in this survey was to study the clinical characteristics of infections caused by Borrelia genospecies in patients with erythema migrans where Borrelial origin was confirmed by polymerase chain reaction. The aim was also to study factors influencing the clinical appearance of erythema migrans. Methods: The study was conducted in southern Sweden from May 2001 to December 2003 on patients 18 years and older attending with erythema migrans at outpatient clinics. All erythema migrans were verified by polymerase chain reaction, photographed and categorized into “annular” or “non-annular” lesions. A logistic regression model was used to analyze relations between the appearance of the erythema migrans (i.e., annular or non-annular) and factors that influenced its clinical appearances. Results: A total of 118 patients, 54 women (45.8%) and 64 men (54.2%), fulfilled the inclusion criteria. Of these patients, 74% were infected by B. afzelii, 26% by B. garinii ( p < 0.001). A total of 45% (38/85) of the erythema migrans were annular, 46% (39/85) were non-annular and 9.4% (8/85) were atypical. For men infected by B. afzelii the odds ratio of developing non-annular erythema migrans was 0.09 (95% CI: 0.03 - 0.33) in comparison with women with the same infection. Conclusions: In this prospective study of a large series of erythema migrans, where infecting genospecies were confirmed by polymerase chain reaction, the sex of patients infected with B. afzelii had a strong influence on the appearance of the rash. Patients infected by B. garinii more often had non-annular erythema migrans and a more virulent infection with more individuals presenting with fever, raised levels of C-reactive protein and seroreactivity in the convalescence sera.
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| 8. |
- Bennet, Louise, et al.
(författare)
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Clinical Aspects of Erythema Migrans in Southern Sweden
- 2005
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Konferensbidrag (refereegranskat)abstract
- Background: The aim of this study was to describe and categorize the different predominant patterns of PCR confirmed erythema migrans (EM) and to study possible correlations according to the clinical pictures and Borrelia substrains. Methods: Patients over 18 years old, seeking care with tick exposure and an EM were consecutively included during a study period of three years. We evaluated clinical and laboratory findings with regard to Borrelia burgdorferi s.l. spirochetes detected with nested Osp A PCR in skin biopsy specimens. Laboratory and serology testing were done acute, after 6 weeks and after 6 months. The patients were clinically evaluated at the initial visit and repeatedly after 14 days unitl recovery. Results: 118 patients (women=54, men=64) with a positive B. Burgdorferi s.l. PCR analysis were included. In this area totally 73.7% of the EM were caused by B. afzelii and 26.3% by B. garinii (p=0.0001). Leisons caused by B. garinii had a shorter duration from tick bite to the initial visit (p= 0.001) but there were no differences between the sizes of the EM, indicating a faster development of lesions caused by B. garinii. Patients with lesions caused by B. garinii to a greater extent had presented with fever at the initial visit (p=0.02). Also patients with B. garinii lesions to a greater extent had elevated levels of CRP at the initial visit (p=0.006). 45% of the EM were categorized as “annular”, 27% as “homogeneous”, 19% as “central erythemas” and 9% as “atypical”. The lesions caused by B. afzelii were predominately “annular” and the lesions caused by B. gaarinii were predominately “homogeneous”. Conclusions: In this study most EM were caused by B. afzelii. Leisons caused by B. garinii developed faster and the patients to a greater extent presented with fever and elevated levels of CRP at the initial visit. Leisons caused by B. garinii were mostly homogenous and by B. afzelii were mostly annular.
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| 9. |
- Berglund, B, et al.
(författare)
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Erythropoietin concentrations during 10 days of normobaric hypoxia under controlled environmental circumstances.
- 2002
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Ingår i: Acta Physiologica Scandinavica. - : Wiley. - 0001-6772 .- 1365-201X. ; 174, s. 225-
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Tidskriftsartikel (refereegranskat)abstract
- Serum erythropoietin levels (s-[epo]), haemoglobin concentration ([Hb]), haematocrit (hct), and ferritin concentration ([fer]) were measured in seven healthy male volunteers (20-23 years) exposed continuously to hypoxia (PO(2) 14 kPa) for 10 days. Serum erythropoietin concentration increased significantly from 9.5 +/- 3.51 to 33.6 +/- 11.64 U L(-1) (P < 0.05) after 2 days of hypoxia. Thereafter, s-[epo] decreased. However, after 10 days s-[epo] was 18.7 +/- 5.83 U L(-1) which was still increased above the pre-hypoxia level (P < 0.05). Serum haemoglobin concentration and hct increased over the 10 days of hypoxia, [Hb] from 152 +/- 8.9 to 168 +/- 9.2 gL(-1) (P < 0.001), and hct from 43 +/- 2.4 to 49 +/- 2.6% (P < 0.001). Ferritin concentration decreased significantly during the hypoxic exposure from 82 +/- 46.9 to 44 +/- 31.7 mmol L(-1) after 10 days (P < 0.01). In conclusion, the initial increase of s-[epo] under controlled normobaric hypoxia was marked, 353%, and levelled off after 5-10 days at 62-97% above normoxia level. There was also a significant increase in [Hb] and hct and a decrease in [fer] after 10 days of exposure to normobaric hypoxia.
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| 10. |
- Berglund-Baudin, Helena, et al.
(författare)
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Intramolecular Electron Transfer from Manganese(II) Coordinatively Linked to a Photogenerated Ru(III)-Polypyridine Complex: A Kinetic Analysis
- 1998
-
Ingår i: The Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory. - : American Chemical Society (ACS). - 1520-5215. ; 102:15, s. 2512-2518
-
Tidskriftsartikel (refereegranskat)abstract
- For further investigations in the field of artificial photosynthesis, a model compound, 1, has been developed to mimic the electron-transfer steps from the manganese cluster to P680+ in photosystem II. In this model compound the photosensitizer ruthenium(II)-trisbipyridyl was linked to a manganese(II) ion through a bridging ligand. Photoexcitation of 1 in the presence of the electron acceptor methyl viologen (MV2+) lead to electron transfer from the Ru moiety to MV2+. Laser flash photolysis experiments at different concentrations of 1 were performed in order to follow the subsequent reduction of the photooxidized Ru(III) species. A kinetic model, taking different parallel reactions into account, could explain the experimental data. It was shown that the major part of the photooxidized Ru(III) created was reduced again by intramolecular electron transfer from the attached Mn(II), with a rate constant of 1.8 × 105 s-1. However, Mn(II) was partially dissociated from 1, giving a fraction of Ru(III) without Mn(II) attached. In these complexes electron transfer could occur only after a rate-limiting reassociation of Mn(II), with a rate constant 2.9 × 109 M-1 s-1. In the analysis of the data, the fraction of dissociated Mn(II) could be determined independently at each concentration of 1, utilizing the fact that bound Mn(II) quenched the excited state, probably by energy transfer.
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| 11. |
- Berglund, Erik, et al.
(författare)
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Distributed Newton Method Over Graphs : Can Sharing of Second-Order Information Eliminate the Condition Number Dependence?
- 2021
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Ingår i: IEEE Signal Processing Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1070-9908 .- 1558-2361. ; 28, s. 1180-1184
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Tidskriftsartikel (refereegranskat)abstract
- One of the main advantages of second-order methods in a centralized setting is that they are insensitive to the condition number of the objective function's Hessian. For applications such as regression analysis, this means that less pre-processing of the data is required for the algorithm to work well, as the ill-conditioning caused by highly correlated variables will not be as problematic. Similar condition number independence has not yet been established for distributed methods. In this paper, we analyze the performance of a simple distributed second-order algorithm on quadratic problems and show that its convergence depends only logarithmically on the condition number. Our empirical results indicate that the use of second-order information can yield large efficiency improvements over first-order methods, both in terms of iterations and communications, when the condition number is of the same order of magnitude as the problem dimension.
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| 12. |
- Berglund, Elisabeth, et al.
(författare)
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High incidence of infective endocarditis in adults with congenital ventricular septal defect
- 2016
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Ingår i: Heart. - : BMJ. - 1355-6037 .- 1468-201X. ; 102:22, s. 1835-1839
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Ventricular septal defects (VSDs), if haemodynamically important, are closed whereas small shunts are left without intervention. The long-term prognosis in congenital VSD is good but patients are still at risk for long-term complications. The aim of this study was to clarify the incidence of infective endocarditis (IE) in adults with VSD. METHODS: The Swedish registry for congenital heart disease (SWEDCON) was searched for adults with VSD. 779 patients were identified, 531 with small shunts and 248 who had the VSD previously closed. The National Patient Register was then searched for hospitalisations due to IE in adults during a 10-year period. RESULTS: Sixteen (2%) patients were treated for IE, 6 men and 10 women, with a mean age of 46.3+/-12.2 years. The incidence of IE was 1.7-2.7/1000 years in patients without previous intervention, 20-30 times the risk in the general population. Thirteen had small shunts without previous intervention. There was no mortality in these 13 cases. Two patients had undergone repair of their VSD and also aortic valve replacement before the episode of endocarditis and a third patient with repaired VSD had a bicuspid aortic valve, all of these three patients needed reoperation because of their IE and one patient died. No patient with isolated and operated VSD was diagnosed with IE. CONCLUSIONS: A small unoperated VSD in adults carries a substantially increased risk of IE but is associated with a low risk of mortality.
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| 13. |
- Berglund, Erik, 1993-
(författare)
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Novel Hessian approximations in optimization algorithms
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There are several benefits of taking the Hessian of the objective function into account when designing optimization algorithms. Compared to using strictly gradient-based algorithms, Hessian-based algorithms usually require fewer iterations to converge. They are generally less sensitive to tuning of parameters and can better handle ill-conditioned problems. Yet, they are not universally used, due to there being several challenges associated with adapting them to various challenging settings. This thesis deals with Hessian-based optimization algorithms for large-scale, distributed and zeroth-order problems. For the large-scale setting, we contribute with a new way of deriving limited memory quasi-Newton methods, which we show can achieve better results than traditional limited memory quasi-Newton methods with less memory for some logistic and linear regression problems. For the distributed setting, we perform an analysis of how the error of a Newton-step is affected by the condition number and the number of iterations of a consensus-algorithm based on averaging, We show that the number of iterations needed to solve a quadratic problem with relative error less than ε grows logarithmically with 1/ε and also with the condition number of the Hessian of the centralized problem. For the zeroth order setting, we exploit the fact that a finite difference estimate of the directional derivative works as an approximate sketching technique, and use this to propose a zeroth order extension of a sketched Newton method that has been developed to solve large-scale problems. With the extension of this method to the zeroth order setting, we address the combined challenge of large-scale and zeroth order problems.
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| 14. |
- Berglund, Erik
(författare)
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Novel Hessian-Based Algorithms for Unconstrained Optimization
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There are several benefits of taking the Hessian of the objective function into account when designing optimization algorithms. Compared to using strictly gradient-based algorithms, Hessian-based algorithms usually require fewer iterations to converge. They are generally less sensitive to tuning of parameters and can better handle ill-conditioned problems. Yet, they are not universally used, due to there being several challenges associated with adapting them to various challenging settings. This thesis deals with Hessian-based optimization algorithms for large-scale, stochastic, distributed, and zeroth-order problems. For the large-scale setting, we contribute with a new way of deriving limited memory quasi-Newton methods, which we show can achieve better results than traditional limited memory quasi-Newton methods with less memory for some logistic and linear regression problems. For the stochastic setting, we relax the secant condition used in traditional quasi-Newton methods and derive a novel quasi-Newton update that always preserves positive definiteness. Based on this, we develop an algorithm that exhibits linear convergence toward a neighborhood of the optimal solution, even if gradient and function evaluations are subject to bounded perturbations. For the distributed setting, we contribute with two different projects. Firstly, we perform an analysis of how the error of a Newton-step is affected by the condition number and the number of iterations of a consensus-algorithm based on averaging. We show that the number of iterations needed to solve a quadratic problem with relative error less than ε grows logarithmically with 1/ε and also with the condition number of the Hessian of the centralized problem. Secondly, we consider how Hessians and Hessian approximations can be used to compensate for communication delays in asynchronous implementations of the Incremental Aggregated Gradient (IAG) algorithm. We provide a general convergence theorem that can be used to analyze delay compensation using various Hessian approximations, apply it to the previously proposed Curvature-Aided IAG (CIAG), and propose delay compensation with some cheaper Hessian approximations that nevertheless outperform IAG without delay compensation. For the zeroth order setting, we exploit the fact that a finite difference estimate of the directional derivative works as an approximate sketching technique and use this to propose a zeroth order extension of a sketched Newton method that has been developed to solve large-scale problems. With the extension of this method to the zeroth order setting, we address the combined challenge of large-scale and zeroth order problems.
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| 15. |
- Berglund, Erik, et al.
(författare)
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Revisiting the Curvature-aided IAG : Improved Theory and Reduced Complexity
- 2023
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Ingår i: IFAC-PapersOnLine. - : Elsevier BV. - 2405-8963. ; 56:2, s. 5221-5226, s. 5221-5226
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Tidskriftsartikel (refereegranskat)abstract
- The curvature-aided IAG (CIAG) algorithm is an efficient asynchronous optimization method that accelerates IAG using a delay compensation technique. However, existing step-size rules for CIAG are conservative and hard to implement, and the Hessian computation in CIAG is often computationally expensive. To alleviate these issues, we first provide an easy-to-implement and less conservative step-size rule for CIAG. Next, we propose a modified CIAG algorithm that reduces the computational complexity by approximating the Hessian with a constant matrix. Convergence results are derived for each algorithm on both convex and strongly convex problems, and numerical experiments on logistic regression demonstrate their effectiveness in practice.
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| 16. |
- Berglund, Elisabeth, et al.
(författare)
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Ten+ Years of Successful Workplace Learning through Host Company Collaboration
- 2008
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- For a period of more than ten years a very successful Host Company Program has been running at the School of Engineering at Jönköping University (JTH), Sweden. This program enables close collaboration between the university and its staff and the 500 regional host companies (HCs) who support the quality assurance of the engineering education given at the School of Engineering.With the introduction of the principles of CDIO at JTH, the host company program and the engineering methodology course was seen as a pre-existing building block of CDIO. This paper will explain in more detail how the HCP is orchestrated at JTH as well as how it is perceived by university staff, the engineering students, and the HCs. Also, how the HCP fits the principles of CDIO will be discussed further together with what is needed to be refined within the HCP.
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| 17. |
- Berglund, Jennie, et al.
(författare)
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A molecular dynamics study of the effect of glycosidic linkage type in the hemicellulose backbone on the molecular chain flexibility
- 2016
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Ingår i: The Plant Journal. - : John Wiley & Sons Ltd.. - 0960-7412 .- 1365-313X. ; 88:1, s. 56-70
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Tidskriftsartikel (refereegranskat)abstract
- The macromolecular conformation of the constituent polysaccharides in lignocellulosic biomass influences their supramolecular interactions, and therefore their function in plants and their performance in technical products. The flexibility of glycosidic linkages from the backbone of hemicelluloses was studied by evaluating the conformational freedom of the φ and ψ dihedral angles using molecular dynamic simulations, additionally selected molecules were correlated with experimental data by NMR spectroscopy. Three types of β-(1→4) glycosidic linkages involving the monosaccharides (Glcp, Xylp and Manp) present in the backbone of hemicelluloses were defined. Different di- and tetrasaccharides with combinations of such sugar monomers from hemicelluloses were simulated and free energy maps of the φ - ψ space and hydrogen bonding patterns were obtained. The glycosidic linkage between Glc-Glc or Glc-Man (C-type) was the stiffest with mainly one probable conformation; the linkage from Man-Man or Man-Glc (M-type) was similar but with an increased probability for an alternative conformation making it more flexible, and the linkage between two Xyl-units (X-type) was the most flexible with two almost equally populated conformations. Glycosidic linkages of the same type showed essentially the same conformational space in both disaccharides and in the central region of tetrasaccharides. Different probabilities of glycosidic linkage conformations in the backbone of hemicelluloses can be directly estimated from the free energy maps, which to a large degree affect the overall macromolecular conformations of these polymers. The information gained contributes to an increased understanding of hemicelluloses’ function both in the cell wall and in technical products.
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| 18. |
- Berglund, Jennie, et al.
(författare)
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Acetylation and Sugar Composition Influence the (In)Solubility of Plant beta-Mannans and Their Interaction with Cellulose Surfaces
- 2020
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Ingår i: ACS Sustainable Chemistry and Engineering. - : AMER CHEMICAL SOC. - 2168-0485. ; 8:27, s. 10027-10040
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Tidskriftsartikel (refereegranskat)abstract
- Plant beta-mannans are complex heteropolysaccharides that represent an abundant resource from lignocellulosic biomass. The influence of the molecular motifs of plant mannans on the backbone flexibility, solubility, and the interaction with cellulose was investigated by computational and experimental approaches. The regioselectivity of the acetyl substitutions at C2 and C3 distinctively influenced backbone flexibility in aqueous media, as revealed by molecular dynamic simulations. The molecular weight and degree of acetylation were tailored for two model seed mannans (galactomannan and glucomannan) and compared to spruce acetylated galactoglucomannan. The thermal stability was enhanced with increasing acetyl substitutions, independently of the type of mannan. Dynamic light scattering and atomic force microscopy revealed that the occurrence of galactosylation and a low degree of acetylation (similar to that of native acetylated galactoglucomannans) enhanced solubility/dispersibility of mannans, whereas the solubility/dispersibility decreased for higher degrees of acetylation. Mannan solubility influenced their interactions with cellulose at water-cellulose interfaces in terms of adsorbed mass and viscoelastic properties of the adsorbed mannan layers. Our results reveal that modulating the molecular motifs of plant beta-mannans influences their macromolecular conformation and physicochemical properties, with fundamental implications for their role in the plant cell wall and the design of wood-based materials.
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| 19. |
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| 20. |
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| 21. |
- Berglund, Johan, et al.
(författare)
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Multi-scale graph-cut algorithm for efficient water-fat separation
- 2017
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Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 78:3, s. 941-949
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Tidskriftsartikel (refereegranskat)abstract
- PurposeTo improve the accuracy and robustness to noise in water-fat separation by unifying the multiscale and graph cut based approaches to B-0-correction.MethodsA previously proposed water-fat separation algorithm that corrects for B-0 field inhomogeneity in 3D by a single quadratic pseudo-Boolean optimization (QPBO) graph cut was incorporated into a multi-scale framework, where field map solutions are propagated from coarse to fine scales for voxels that are not resolved by the graph cut. The accuracy of the single-scale and multi-scale QPBO algorithms was evaluated against benchmark reference datasets. The robustness to noise was evaluated by adding noise to the input data prior to water-fat separation.ResultsBoth algorithms achieved the highest accuracy when compared with seven previously published methods, while computation times were acceptable for implementation in clinical routine. The multi-scale algorithm was more robust to noise than the single-scale algorithm, while causing only a small increase (+10%) of the reconstruction time.ConclusionThe proposed 3D multi-scale QPBO algorithm offers accurate water-fat separation, robustness to noise, and fast reconstruction. The software implementation is freely available to the research community. Magn Reson Med 78:941-949, 2017.
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| 22. |
- Berglund, Johan, et al.
(författare)
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New Test Method for Detection and Analysis of Burrs and Slivers in Trimming and Punching Aluminium Sheet Metal
- 2014
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A large problem when trimming or punching aluminium sheet is thecreation of burrs and slivers which degrade the quality of the produced parts. A semiindustrial test for evaluating trimming of aluminium has been further developed toinclude pre-stressing and pre-straining of the sheet material before trimming. Thesemi-industrial test results now show good correlation to industrial productionoutcomes.
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| 23. |
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| 24. |
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| 25. |
- Berglund, Jennie, et al.
(författare)
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The structure of galactoglucomannan impacts the degradation under alkaline conditions
- 2018
-
Ingår i: Cellulose. - : Springer. - 0969-0239 .- 1572-882X.
-
Tidskriftsartikel (refereegranskat)abstract
- Galactoglucomannan (GGM) from sprucewas studied with respect to the degradation behavior inalkaline solution. Three reference systems includinggalactomannan from locust bean gum, glucomannanfrom konjac and the linear water-soluble carboxymethylcellulose were studied with focus onmolecular weight, sugar composition, degradationproducts, as well as formed oligomers, to identifyrelative structural changes in GGM. Initially allmannan polysaccharides showed a fast decrease inthe molecular weight, which became stable in the laterstage. The degradation of the mannan polysaccharidescould be described by a function corresponding to thesum of two first order reactions; one slow that wasascribed to peeling, and one fast that was connectedwith hydrolysis. The galactose side group wasstable under conditions used in this study (150 min,90 C, 0.5 M NaOH). This could suggest that, apartfrom the covalent connection to C6 in mannose, thegalactose substitutions also interact non-covalentlywith the backbone to stabilize the structure againstdegradation. Additionally, the combination of differentbackbone sugars seems to affect the stability of thepolysaccharides. For carboxymethyl cellulose thedegradation was linear over time which furthersuggests that the structure and sugar composition playan important role for the alkaline degradation. Moleculardynamics simulations gave details about theconformational behavior of GGM oligomers in watersolution, as well as interaction between the oligomersand hydroxide ions.
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| 26. |
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| 27. |
- Berglund, Jennie, et al.
(författare)
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Wood hemicelluloses exert distinct biomechanical contributions to cellulose fibrillar networks
- 2020
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.
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| 28. |
- Berglund, Jennie
(författare)
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Wood Hemicelluloses - Fundamental Insights on Biological and Technical Properties
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hemicelluloses are a group of heterogeneous polysaccharides representing around 30 % of wood where the dominating types are xylans, glucomannans and xyloglucans. Hemicelluloses complex molecular structure makes it difficult to understand the relationship between structure and properties entirely, and their biological role is not yet fully verified. Additionally, hemicelluloses are sensitive to chemical processing and are not utilized to their full potentials for production of value-added products such as materials, additives to food and pharmaceutical products, etc. Increased knowledge regarding their functions is important for the development of both processes and products. The aim with this work has therefore been to increase the fundamental understanding about how the structure and properties of wood hemicelluloses are correlated, and properties such as flexibility, interaction with cellulose, solubility, resistance to chemical-, thermal-, and enzymatic degradation have been explored.Molecular dynamics (MD) simulations were used to, in detail, study the structures found in wood hemicelluloses. The flexibility was evaluated by comparing the impact of backbone sugars on the conformational space and also the impact of side groups was considered. Based on the conformational space of backbone glycosidic linkages the flexibility order of hemicelluloses in an aqueous environment was determined to be: xylan > glucomannan > xyloglucan. Additionally, the impact of xylan structure on cellulose interaction was evaluated by MD methods.Hemicelluloses were extracted from birch and spruce, and were used to fabricate different composite hydrogels with bacterial cellulose. These materials were studied with regards to mechanical properties, and it was shown that galactoglucomannans mainly contributed to an increased modulus in compression, whereas the most significant effect from xylan was increased strain under uniaxial tensile testing. Besides, other polysaccharides of similar structure as galactoglucomannans were modified and used as pure, well defined, models. Acetyl groups are naturally occurring decorations of wood hemicelluloses and can also be chemically introduced. Here, mannans with different degrees of acetylation were prepared and the influence of structure on solubility in water and the organic solvent DMSO were evaluated. Furthermore, the structure and water solubility influenced the interaction with cellulose. Acetylation also showed to increase the thermal and biological stability of mannans.With chemical pulping processes in mind, the degradability of spruce galactoglucomannans in alkaline solution were studied with regards to the structure, and the content of more or less stable structural regions were proposed.
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| 29. |
- Berglund, Lisa, et al.
(författare)
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Nuclear Factor of Activated T Cells Regulates Osteopontin Expression in Arterial Smooth Muscle in Response to Diabetes-Induced Hyperglycemia
- 2010
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Ingår i: ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY. - Baltimore : Lippincott Williams & Wilkins. - 1079-5642. ; 30, s. 154-218
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Tidskriftsartikel (refereegranskat)abstract
- Objective-Hyperglycemia is a recognized risk factor for cardiovascular disease in diabetes. Recently, we reported that high glucose activates the Ca2+/calcineurin-dependent transcription factor nuclear factor of activated T cells (NFAT) in arteries ex vivo. Here, we sought to determine whether hyperglycemia activates NFAT in vivo and whether this leads to vascular complications. Methods and Results-An intraperitoneal glucose-tolerance test in mice increased NFATc3 nuclear accumulation in vascular smooth muscle. Streptozotocin-induced diabetes resulted in increased NFATc3 transcriptional activity in arteries of NFAT-luciferase transgenic mice. Two NFAT-responsive sequences in the osteopontin (OPN) promoter were identified. This proinflammatory cytokine has been shown to exacerbate atherosclerosis and restenosis. Activation of NFAT resulted in increased OPN mRNA and protein in native arteries. Glucose-induced OPN expression was prevented by the ectonucleotidase apyrase, suggesting a mechanism involving the release of extracellular nucleotides. The calcineurin inhibitor cyclosporin A or the novel NFAT blocker A-285222 prevented glucose-induced OPN expression. Furthermore, diabetes resulted in higher OPN expression, which was significantly decreased by in vivo treatment with A-285222 for 4 weeks or prevented in arteries from NFATc3(-/-) mice. Conclusions-These results identify a glucose-sensitive transcription pathway in vivo, revealing a novel molecular mechanism that may underlie vascular complications of diabetes.
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| 30. |
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| 31. |
- Berglund, Mikael
(författare)
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Early Holocene in Gästrikland, east central Sweden : shore displacement and pattern of isostatic recovery
- 2012
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Ingår i: Boreas. - : Wiley-Blackwell. - 0300-9483 .- 1502-3885. ; 41:2, s. 263-276
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Tidskriftsartikel (refereegranskat)abstract
- In Gästrikland in central Sweden, deglaciation took place c. 11 000 cal. a BP. In the present study the shore displacement during the earliest ice-free period is investigated by the 14C dating of sediment from isolated lake basins. The shore displacement in Gästrikland includes an initial phase (∼500 years) of rapid regression, followed by a slowing of the relative sea level (RSL) fall to a rate similar to that of the remaining Holocene c. 9250 cal. a BP. The Ancylus Lake stage of the Baltic Sea belongs to the analysed interval. The RSL curve and glacial unloading history are used to separate and quantify elements of isostatic uplift. The postglacial uplift is ∼260 m, of which ∼45 m forms a rapid initial rise, which can be treated as qualitatively separate from the later, slower rise. There is considerable glacial unloading just prior to the deglaciation, but calculations suggest that only a small part of this relates directly to the rapid early Holocene rebound: most unloading is transferred either to uplift immediately prior to the deglaciation or to subsequent Holocene or future uplift. The isostatic rise in Gästrikland occurring between the end of the Younger Dryas stadial and the deglaciation, c. 11 500–11 000 cal. a BP, is estimated to be 100–110 m. Observations and estimations are incompatible with a Weichselian maximum ice thickness much smaller that 3000 m. The lack of glacial unloading during the Younger Dryas has a measurable impact on the Holocene isostatic rebound in Gästrikland, reducing it by an estimated 20–25 m.
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| 32. |
- Berglund, Mikael
(författare)
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Holocene shore displacement and chronology in Ångermanland, eastern Sweden, the Scandianvian glacio-isostatic uplift centre
- 2004
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Ingår i: Boreas. - : Wiley. - 0300-9483 .- 1502-3885. ; 33:1, s. 48-60
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Tidskriftsartikel (refereegranskat)abstract
- The shore displacement during the Holocene in southeastern Ångermanland, Sweden, has been investigated by means of radiocarbon-dating of isolation intervals in sediment cores from a total of nine new basins. Results from earlier investigations have been used in complement. There is a forced regression in the area from c. 9300 BP (c. 10 500 cal. yr BP) until c. 8000 BP (c. 9000 cal. yr BP), on average c. 8 m/100 years, after which there is a gradually slowing regression of c. 2.5-1.0 m/100 years up to the present time. The most rapid regression occurs during the later phase of the Ancylus Lake stage, 9500-9000 cal. yr BP. There is no evidence of halts in the regression. Crustal uplift in the area since deglaciation is c. 310 m. The deglaciation of southeastern Ångermanland took place c. 9300 BP (c. 10 500 cal. yr BP); this is c. 900 years earlier than the age given by clay varve dating. The shore displacement curve provides a means of estimating the difference between the clay varve time scale and calibrated radiocarbon dates, by comparison with varve-dated altitudes of alluvial deltas of the River Ångermanälven. From c. 2500 to c. 8000 cal. BP there is a deficit in clay varves of some 300 years; further back in time this discrepancy increases significantly. The main explanation for the discrepancy is most likely lacking varves in the time-span 8500-10 200 cal. yr BP, located along the upper reaches of River Ångermanälven below the highest shore level
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| 33. |
- Berglund, Mikael
(författare)
-
Holocene shore displacement and chronology in Ångermanland, eastern Sweden, the Scandinavian glacio-isostatic uplift centre
- 2004
-
Ingår i: Boreas. - Oslo : Taylor & Francis. - 0300-9483 .- 1502-3885. ; 33, s. 48-60
-
Tidskriftsartikel (refereegranskat)abstract
- The shore displacement during the Holocene in southeastern Ångermanland, Sweden, has been investigated by means of radiocarbon-dating of isolation intervals in sediment cores from a total of nine new basins. Results from earlier investigations have been used in complement. There is a forced regression in the area from c. 9300 BP (c. 10500 cal. yr BP) until c. 8000 BP (c. 9000 cal. yr BP), on averagec. 8 m/100 years, after which there is a gradually slowing regression of c. 2.5–1.0 m/100 years up to the present time. The most rapid regression occurs during the later phase of the Ancylus Lake stage, 9500–9000 cal. yr BP. There is no evidence of halts in the regression. Crustal uplift in the area since deglaciation is c. 310 m. The deglaciation of southeastern Ångermanland took place c. 9300 BP (c. 10500 cal. yr BP); this is c. 900 years earlier than the age given by clay varve dating. The shore displacement curve provides a means of estimating the difference between the clay varve time scale and calibrated radiocarbon dates, by comparison with varve-dated altitudes of alluvial deltas of the River Ångermanalven. From c. 2500 to c. 8000 cal. BP there is a deficit in clay varves of some 300 years; further back in time this discrepancy increases significantly. The main explanation for the discrepancy is most likely lacking varves in the time-span 8500–10200 cal. yr BP, located along the upper reaches of River Ångermanalven below the highest shore level.
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| 34. |
- Berglund, Martin, 1980, et al.
(författare)
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Investigations of a compartmental model for leucine kinetics using non-linear mixed effects models with ordinary and stochastic differential equations.
- 2012
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Ingår i: Mathematical Medicine and Biology. - : Oxford University Press (OUP). - 1477-8599 .- 1477-8602. ; 29:4, s. 361-384
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Tidskriftsartikel (refereegranskat)abstract
- Non-linear mixed effects (NLME) models represent a powerful tool to simultaneously analyse data from several individuals. In this study, a compartmental model of leucine kinetics is examined and extended with a stochastic differential equation to model non-steady-state concentrations of free leucine in the plasma. Data obtained from tracer/tracee experiments for a group of healthy control individuals and a group of individuals suffering from diabetes mellitus type 2 are analysed. We find that the interindividual variation of the model parameters is much smaller for the NLME models, compared to traditional estimates obtained from each individual separately. Using the mixed effects approach, the population parameters are estimated well also when only half of the data are used for each individual. For a typical individual, the amount of free leucine is predicted to vary with a standard deviation of 8.9% around a mean value during the experiment. Moreover, leucine degradation and protein uptake of leucine is smaller, proteolysis larger and the amount of free leucine in the body is much larger for the diabetic individuals than the control individuals. In conclusion, NLME models offers improved estimates for model parameters in complex models based on tracer/tracee data and may be a suitable tool to reduce data sampling in clinical studies.
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| 35. |
- Berglund, Mikael
(författare)
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Litorina Sea shore displacement and pollen analytical indications of forest succession during the Mid-Holocene in Gästrikland, east central Sweden
- 2010
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Ingår i: GFF. - Stockholm : Taylor & Francis. - 1103-5897 .- 2000-0863. ; 132:3, s. 213-226
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Tidskriftsartikel (refereegranskat)abstract
- This paper deals with the mid-Holocene shore level history and vegetation development in Gästrikland, east-central Sweden. This is investigated using sediment and microfossil records and 14C datings. The time span covered is c. 8000-5000 cal yr BP. Vegetation history during this time includes an increase in Tilia pollen 6500-6300 cal yr BP and a decrease in Ulmus and Corylus c. 5500 cal yr BP. The former change coincides with a sharp drop in relative sea level (RSL) of some 5 m; this RSL drop can be correlated to the regression from the L3 transgression of the Litorina Sea, identified in other areas around the Baltic Sea. The possible connections between RSL and climate (in particular changes on a maritime-continental continuum), as indicated by new pollen data and other records, are investigated. The new material shows, in comparison to other pollen records from southern and central Scandinavia, unusually high percentages of Tilia, Ulmus and Corylus pollen, but less Quercus. The change in pollen spectra around 5500 cal yr BP can be correlated to the northern European “elm decline”. A regional cooling is recorded in widespread data for this time, but observations suggest that other factors must be considered here, including disease and change in the physical landscape due to the ongoing land uplift.
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| 36. |
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| 37. |
- Berglund, Mikael, 1965-, et al.
(författare)
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Post-glacial fault scarps in Jämtland, central Sweden
- 2015
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Ingår i: GFF. - : Informa UK Limited. - 1103-5897 .- 2000-0863. ; 137:4, s. 339-343
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of a light detection and ranging-derived digital elevation model has revealed previously unknown fault scarps in central Jämtland, Sweden. These are interpreted to have been formed by earthquakes at the time of deglaciation, c. 10 ka BP, in an area with current low-magnitude seismicity. The dating is based upon morphology and comparison with similar features at other locations in Sweden but not supported by independent dating. Observed scarps are 0.4–6 km long, 2–8 m high, trending SSW–NNE to WSW–ENE, the northern and western sides uplifted. The dimensions of the scarps suggest an approximate moment magnitude M 7 of the strongest corresponding earthquakes.
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| 38. |
- Berglund, Mikael
(författare)
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The highest postglacial shore levels and glacio-isostatic uplift pattern in northern Sweden
- 2012
-
Ingår i: Geografiska Annaler. Series A, Physical Geography. - : Swedish Society for Anthropology and Geography. - 0435-3676 .- 1468-0459. ; 94:3, s. 321-337
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Tidskriftsartikel (refereegranskat)abstract
- The detailed clay varve chronology and an extensive knowledge of the highest postglacial shore level elevation (HS) in northern Sweden, along the Bothnian western coast, provides opportunities for determining the pattern of isostatic rise and centre of uplift from the early Holocene. The shore level of c. 10 100 cal yr bp (10 ka) for this area is determined by subtracting, from the metachronous HS elevations, the fall in relative sea level between local deglaciation time and the chosen reference time. The area of highest uplift since 10 ka is situated somewhat north of the location with the world-record HS (Skuleberget in Angermanland), but south of the area with most rapid current rise. Wave erosion marks in the studied area are seen to be more consistent indicators of HS than glaciofluvial delta levels. The gradients of shore marks at 10 ka are generally small within the investigation area. The regional 10 ka shore level pattern shows considerable irregularity compared to the current uplift. Central Sweden and western Finland show 10 ka gradients that indicate isostatic response to late (1310 ka bp) glacial unloading. Indications of a secondary uplift centre west of the present investigation area are reported in previous work; this also suggests rapid isostatic response to unloading. Finally, the possibility of identifying errors in the varve-dated deglaciation chronology via the 10 ka shore level pattern is illustrated.
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| 39. |
- Berglund, Mikael
(författare)
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The Holocene shore displacement of Gästrikland, eastern Sweden : A contribution to the knowledge of Scandinavian glacio-isostatic uplift
- 2005
-
Ingår i: Journal of Quaternary Science. - : Wiley. - 0267-8179 .- 1099-1417. ; 20:6, s. 519-531
-
Tidskriftsartikel (refereegranskat)abstract
- The shore displacement in Gästrikland, east-central Sweden, has been investigated by means of AMS radiocarbon dating of sediment cores from isolated basins. Twenty dates from 11 sites are presented. Pollen and diatom analyses, and archive material from the Geological Survey of Sweden, have been used to identify isolation intervals in the cores and as chronological support to the 14C dates. An important pollen stratigraphical time-marker is a distinct mid-Holocene increase in Tilia. For the mid-Holocene, pollen stratigraphy is used rather than the 14C dates for the age determination. The deglaciation of Gästrikland, according to the new 14C dates, took place ca. 11 000 cal. yr BP (ca. 9500 14C yr BP). Through the Holocene the shore displacement is regressive. The regression was initially rapid (on average ca. 3.5 m per 100 yr 11 000-7500 cal. yr BP, probably much more rapid at the earliest stage), then slowed down considerably and was from ca. 5000 cal. yr BP (probably already from 7000 cal. yr BP) relatively constant, ca. 0.8-0.9 m per 100 yr. There are important differences between the shore level curve from Gästrikland and curves from other areas, indicating some irregularities in the regional glacio-isostatic rebound.
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| 40. |
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| 41. |
- Berglund, Mikael
(författare)
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Time-transgressive early Holocene vegetational succession following shore displacement: a case study from central Sweden
- 2008
-
Ingår i: Boreas. - : Wiley. - 0300-9483 .- 1502-3885. ; 37:1, s. 87-101
-
Tidskriftsartikel (refereegranskat)abstract
- Deglaciation took place in eastern Jamtland and Angermanland in central Sweden c. 10 500 - 10 200 cal. yr BP. In the present study, vegetation development and shore displacement during the earliest ice-free period are investigated by C-14 dating of sediment from six isolated lake basins and by pollen analysis. A brief but distinct peak in Hippophae "occurs in all pollen diagrams coincident with basin isolation, followed by up to 500 years ( varying locally) by an Alnus rise. The Alnus curve does not display a synchronous rise in the area. Its expansion below the highest shore level is time-transgressive and controlled mainly by the timing of basin isolation. The relationship between regional Alnus expansion and changes in hydrology and climate is discussed. The pollen diagrams show Pinus predominance with Corylus to the east ( more coastal areas) and Betula predominance ( though less pronounced) to the west during the period 10 200 - 9000 cal. yr BP. However, comparisons between sites suggest marked variability in the forest development. Shore displacement in easternmost Jamtland c. 10 300 - 9000 cal. yr BP is equal to or slightly more rapid than that of SE Angermanland, contrary to the present pattern of isostatic recovery. A rapid shore level regression c. 10 300 - 10 000 cal. yr BP may be related to drainage of the Ancylus Lake.
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| 42. |
- Berglund, Sofia, et al.
(författare)
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Granulocyte transfusions could benefit patients with severe oral mucositis after allogeneic hematopoietic stem cell transplantation
- 2019
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Ingår i: Vox Sanguinis. - : Wiley-Blackwell. - 0042-9007 .- 1423-0410. ; 114:7, s. 769-777
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Tidskriftsartikel (refereegranskat)abstract
- Background and objectives Mucositis is a common complication after allogeneic hematopoietic stem cell transplantation (HSCT), and is caused by a combination of conditioning-induced mucosal damage and severe neutropenia. The symptoms include oral and abdominal pain, inability to swallow food and fluids, and severe diarrhoea. Severe mucositis is associated with increased risk of Graft-versus-Host disease and infection. Granulocyte transfusions (GCX) could be a treatment option, and our objective was to study its feasibility and potential benefits. Material and methods This retrospective, single-centre study included 30 patients receiving GCX because of severe oral mucositis after HSCT during 2005-2017. Clinical outcome, response to GCX, change in opiate administration and adverse events were studied. Results Twenty-seven patients received GCX from donors pre-treated with steroids and G-CSF, and three from donors pre-treated with steroids only. Overall response was 83% (24/29 evaluable patients). Fifteen patients reached a complete response. In 14 of 24 responders, a reduction of the administration of opiate pain relief was seen. In eight patients this reduction was >= 50% of the dose. Adverse events (AEs) were reported in 14 cases, and were mild to moderate, and well manageable with symptomatic treatment. No life-threatening or fatal AEs were recorded. Conclusions These results indicate that GCX could be a safe and effective treatment for oral mucositis after HSCT with the potential to reduce the necessity of opiate analgesic treatment in this disorder. No severe AEs were seen in this study, but the risk for severe pulmonary AEs after GCX needs to be considered.
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| 43. |
- Berglund, Staffan K., et al.
(författare)
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Effects of iron supplementation of low-birth-weight infants on cognition and behavior at 7 years : a randomized controlled trial
- 2018
-
Ingår i: Pediatric Research. - New York : Nature Publishing Group. - 0031-3998 .- 1530-0447. ; 83, s. 111-118
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Tidskriftsartikel (refereegranskat)abstract
- Background Low-birth-weight infants (LBW) are at an increased risk of iron deficiency that has been associated with impaired neurodevelopment. We hypothesized that iron supplementation of LBW infants improves cognitive scores and reduces behavioral problems until school age.Methods We randomized 285 marginally LBW (2,000-2,500 g) infants to receive 0, 1, or 2 mg/kg/day of iron supplements from 6 weeks to 6 months of age. At 7 years of age, 205 participants were assessed regarding cognition using Wechsler Intelligence Scale for Children (WISC-IV) and behavior using the parental questionnaires Child Behavior Checklist (CBCL) and Five to Fifteen (FTF).Results There were no significant differences between the intervention groups in WISC-IV or FTF. However, the CBCL scores for externalizing problems were significantly different, in favor of supplemented children (P=0.045). When combining the supplemented groups, they had significantly lower scores for externalizing behavior compared with placebo (median (interquartile range): 44 [34;51] vs. 48.5 [41;56] P=0.013), and their risk ratio (95% confidence interval) for a total behavioral score above the cutoff for clinical problems was 0.31 (0.09-1.0), P=0.054.Conclusion Lower scores of externalizing behavior in supplemented children support our previous findings at 3 years, and suggest that iron supplementation may have long-lasting effects on behavioral functions.
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| 44. |
- Berglund, Staffan K., et al.
(författare)
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Marginally low birth weight increases the risk of underweight and short stature at three and a half years of age
- 2016
-
Ingår i: Acta Paediatrica. - : John Wiley & Sons. - 0803-5253 .- 1651-2227. ; 105:6, s. 610-617
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Little is known about the long-term health of marginally low birth weight (LBW) children. This study characterised growth among infants weighing 2,000g-2,500g and explored the prevalence and predictors of sustained growth restriction.METHOD: This prospective observational trial followed the weight and height of 281 Swedish marginally LBW children from birth to 3.5 years of age. Children with a standard deviation score (SDS) for body mass index or height below -2 were considered underweight and short respectively.RESULTS: The mean SDS for weight and height showed a rapid increase before 12-19 weeks of age. The most rapid weight gain was in infants born small for gestational age. However, at 3.5 years of age, 9.5% of the children remained underweight and 6.5% had short stature. Regression models showed that slow weight gain before 19 weeks of age was the strongest predictor for lasting underweight, while slow height gain before 19 weeks of age and male sex were associated with short stature.CONCLUSION: Marginally LBW infants were more likely to be underweight and have a short stature at 3.5 years of age and the absence of catch-up growth during the first five months after birth identified those at highest risk.
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| 45. |
- Berglund, T., et al.
(författare)
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High velocity compaction of high speed steel powder : possibilities and constraints
- 2007
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Ingår i: Proceedings of the Euro Powder Metallurgy Congress and Exhibition, Euro PM 2007. ; , s. 21-26
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Konferensbidrag (refereegranskat)abstract
- It is known that gas atomized powders as well as high alloyed metal powders are difficult to press into green bodies using conventional quasi static pressing techniques. However, the development of the high velocity compaction (HVC) technique has expanded the possibility to compact a larger spectrum of metal powders. Although the HVC technique has many similarities with conventional pressing techniques, the high energy impact makes it an interesting technique not only for the pressing of conventional metal powders to green bodies of high density but also for the pressing of "difficult to press metal powders". Today, high speed steel (HSS) is increasingly being used in different types of components. Consequently, there is an increasing interest in the near net shape manufacturing of HSS components. The aim of the present study is to evaluate the possibility to utilize HVC to press green bodies from different types of HSS powder covering both gas and water atomized HSS powders. The results show that the HSS powders investigated differ with respect to compaction properties, i.e. compressibility and green body quality. While the water atomized powders exhibit very good compaction properties, resulting in green bodies of high density, good surface finish and high strength, the gas atomized powders cannot be pressed in the as-atomized condition using HVC. However, agglomerated as well as milled gas atomized HSS powders show significant improved compaction properties compared to the as-atomized powders, although all showed defects of varying sizes depending on the applied energy during compaction.
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| 46. |
- Berner, Jesica, et al.
(författare)
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Case management for frail older adults through tablet computers and Skype
- 2016
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Ingår i: Informatics for Health and Social Care. - : Taylor & Francis. - 1753-8157 .- 1753-8165. ; 41:4, s. 405-416
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Tidskriftsartikel (refereegranskat)abstract
- Background: Frail older adults are high consumers of medical care due to their age and multiple chronic conditions. Regular contact with a case manager has been proven to increase well-being of frail older adults and reduce their number of health-care visits. Skype calls through tablet PCs can offer easier communication. Objective: This paper examines frail older adults’ use of tablet computers and Skype, with their case managers.Method: Interviews were conducted on 15 frail older adults. A content analysis was used to structure and analyze the data. Results: The results indicate that tablet computers were experienced in a positive way for most frail older adults. Conflicting feelings did emerge, however, as to whether the frail elderly would adopt this in the long run. Skype needs to be tested further as to whether this is a good solution for communication with their case managers. Strong technical support and well-functioning technology are important elements to facilitate use. Conclusion: Using Skype and tablet PCs do have potential for frail older adults, but need to be tested further.
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| 47. |
- Berner, Jessica, et al.
(författare)
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Distribution of personality, individual characteristics and internet usage in Swedish older adults
- 2012
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Ingår i: Aging and Mental Health. - : Taylor and Francis. - 1360-7863 .- 1364-6915. ; 16:1, s. 119-126
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: This paper investigated factors associated with internet usage in the Swedish older adults ranging in age from 60 to 96. Personality traits and individual characteristics have been previously noted to influence internet usage, where older adults have not been the focus population. In this study the relationships between personality, individual characteristics and internet usage were investigated. Methods: A descriptive analysis of the personality tests of a total of 1402 subjects included in the Swedish National Study on Aging and Care (SNAC) was conducted. Three variables were controlled for: sex, age and education. Descriptive statistics, Mann-Whitney and Kruskal-Wallis tests, chi square tests and a logistic regression were used in order to detect the relationships with internet usage. Results: Men differ significantly from women in the personality traits analysis. Those with higher education were more open and neuroticism was lower in the oldest older adults. Internet usage declined significantly with age and those with middle to higher education were using the internet the most. No other associations with internet use were found Conclusion: Personality traits and individual characteristics do not seem to influence the Swedish older adult and their internet usage. What one needs to account for is the age and education of the person. The more educated and the youngest cohorts were using the internet more frequently.
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| 48. |
- Berner, Jessica, et al.
(författare)
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Factors associated with change in Internet usage of Swedish older adults (2004-2010)
- 2013
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Ingår i: Health Informatics Journal. - : Sage Publications. - 1460-4582 .- 1741-2811. ; 19:2, s. 152-162
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Tidskriftsartikel (refereegranskat)abstract
- The increased reliance on Internet use in social functions has presumably left out a part of the population: the oldest-older adults. These are people who have not kept themselves up to date with the technological developments for various reasons. There are, however, exceptions from whom we have something to learn. This study investigates the older people in Sweden who started to use the Internet over a period of 6 years. Cognition, extraversion, openness, functional disability, household economy, sex, age and education were investigated in relation to starting to use the Internet. A chi-square test, Spearman correlation and a logistic regression analysis were conducted. It was found that higher cognition, being male and being between the ages of 60 and 80 years were determining factors in starting to use the Internet for the Swedish older adult. Our results indicate that the oldest-older adults are slow to adapt to using the Internet and more attention should be paid on how to support this group.
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| 49. |
- Berner, Jessica, et al.
(författare)
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Factors associated with change in Internet usage of the swedish older adults between 2004 and 2010
- 2012
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Ingår i: Health Informatics Journal. - : SAGE Publications. - 1460-4582 .- 1741-2811. ; 19:2, s. 152-162
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Tidskriftsartikel (refereegranskat)abstract
- Abstract: The increased reliance on Internet use in social functions has presumably left out a part of the population: the oldest-older adults. These are people who have not kept themselves up to date with the technological developments for various reasons. There are, however, exceptions from whom we have something to learn. This study investigates the older people in Sweden who started to use the Internet over a period of 6 years. Cognition, extraversion, openness, functional disability, household economy, sex, age and education were investigated in relation to starting to use the Internet. A chi-square test, Spearman correlation and a logistic regression analysis were conducted. It was found that higher cognition, being male and being between the ages of 60 and 80 years were determining factors in starting to use the Internet for the Swedish older adult. Our results indicate that the oldest-older adults are slow to adapt to using the Internet and more attention should be paid on how to support this group.
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| 50. |
- Berner, Jessica, et al.
(författare)
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Factors influencing Internet usage in older adults (65 years and above) living in rural and urban Sweden
- 2015
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Ingår i: Health Informatics Journal. - : Sage Publications. - 1460-4582 .- 1741-2811. ; 21:3, s. 237-249
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Tidskriftsartikel (refereegranskat)abstract
- Older adults living in rural and urban areas have shown to distinguish themselves in technology adoption; a clearer profile of their Internet use is important in order to provide better technological and health-care solutions. Older adults' Internet use was investigated across large to midsize cities and rural Sweden. The sample consisted of 7181 older adults ranging from 59 to 100 years old. Internet use was investigated with age, education, gender, household economy, cognition, living alone/or with someone and rural/urban living. Logistic regression was used. Those living in rural areas used the Internet less than their urban counterparts. Being younger and higher educated influenced Internet use; for older urban adults, these factors as well as living with someone and having good cognitive functioning were influential. Solutions are needed to avoid the exclusion of some older adults by a society that is today being shaped by the Internet.
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